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Cimini M, Hansmann UHE, Gonzalez C, Chesney AD, Truongcao MM, Gao E, Wang T, Roy R, Forte E, Mallaredy V, Thej C, Magadum A, Joladarashi D, Benedict C, Koch WJ, Tükel Ç, Kishore R. Podoplanin Positive Cell-derived Extracellular Vesicles Contribute to Cardiac Amyloidosis After Myocardial Infarction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.28.601297. [PMID: 39005419 PMCID: PMC11244852 DOI: 10.1101/2024.06.28.601297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Background Amyloidosis is a major long-term complication of chronic disease; however, whether it represents one of the complications of post-myocardial infarction (MI) is yet to be fully understood. Methods Using wild-type and knocked-out MI mouse models and characterizing in vitro the exosomal communication between bone marrow-derived macrophages and activated mesenchymal stromal cells (MSC) isolated after MI, we investigated the mechanism behind Serum Amyloid A 3 (SAA3) protein overproduction in injured hearts. Results Here, we show that amyloidosis occurs after MI and that amyloid fibers are composed of macrophage-derived SAA3 monomers. SAA3 overproduction in macrophages is triggered by exosomal communication from a subset of activated MSC, which, in response to MI, acquire the expression of a platelet aggregation-inducing type I transmembrane glycoprotein named Podoplanin (PDPN). Cardiac MSC PDPN+ communicate with and activate macrophages through their extracellular vesicles or exosomes. Specifically, MSC PDPN+ derived exosomes (MSC PDPN+ Exosomes) are enriched in SAA3 and exosomal SAA3 protein engages with Toll-like receptor 2 (TRL2) on macrophages, triggering an overproduction and impaired clearance of SAA3 proteins, resulting in aggregation of SAA3 monomers as rigid amyloid deposits in the extracellular space. The onset of amyloid fibers deposition alongside extra-cellular-matrix (ECM) proteins in the ischemic heart exacerbates the rigidity and stiffness of the scar, hindering the contractility of viable myocardium and overall impairing organ function. Using SAA3 and TLR2 deficient mouse models, we show that SAA3 delivered by MSC PDPN+ exosomes promotes post-MI amyloidosis. Inhibition of SAA3 aggregation via administration of a retro-inverso D-peptide, specifically designed to bind SAA3 monomers, prevents the deposition of SAA3 amyloid fibrils, positively modulates the scar formation, and improves heart function post-MI. Conclusion Overall, our findings provide mechanistic insights into post-MI amyloidosis and suggest that SAA3 may be an attractive target for effective scar reversal after ischemic injury and a potential target in multiple diseases characterized by a similar pattern of inflammation and amyloid deposition. NOVELTY AND SIGNIFICANCE What is known? Accumulation of rigid amyloid structures in the left ventricular wall impairs ventricle contractility.After myocardial infarction cardiac Mesenchymal Stromal Cells (MSC) acquire Podoplanin (PDPN) to better interact with immune cells.Amyloid structures can accumulate in the heart after chronic inflammatory conditions. What information does this article contribute? Whether accumulation of cumbersome amyloid structures in the ischemic scar impairs left ventricle contractility, and scar reversal after myocardial infarction (MI) has never been investigated.The pathophysiological relevance of PDPN acquirement by MSC and the functional role of their secreted exosomes in the context of post-MI cardiac remodeling has not been investigated.Amyloid structures are present in the scar after ischemia and are composed of macrophage-derived Serum Amyloid A (SAA) 3 monomers, although mechanisms of SAA3 overproduction is not established. SUMMARY OF NOVELTY AND SIGNIFICANCE Here, we report that amyloidosis, a secondary phenomenon of an already preexisting and prolonged chronic inflammatory condition, occurs after MI and that amyloid structures are composed of macrophage-derived SAA3 monomers. Frequently studied cardiac amyloidosis are caused by aggregation of immunoglobulin light chains, transthyretin, fibrinogen, and apolipoprotein in a healthy heart as a consequence of systemic chronic inflammation leading to congestive heart failure with various types of arrhythmias and tissue stiffness. Although chronic MI is considered a systemic inflammatory condition, studies regarding the possible accumulation of amyloidogenic proteins after MI and the mechanisms involved in that process are yet to be reported. Here, we show that SAA3 overproduction in macrophages is triggered in a Toll-like Receptor 2 (TLR2)-p38MAP Kinase-dependent manner by exosomal communication from a subset of activated MSC, which, in response to MI, express a platelet aggregation-inducing type I transmembrane glycoprotein named Podoplanin. We provide the full mechanism of this phenomenon in murine models and confirm SAA3 amyloidosis in failing human heart samples. Moreover, we developed a retro-inverso D-peptide therapeutic approach, "DRI-R5S," specifically designed to bind SAA3 monomers and prevent post-MI aggregation and deposition of SAA3 amyloid fibrils without interfering with the innate immune response.
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Wang J, He M, Yang M, Ai X. Gut microbiota as a key regulator of intestinal mucosal immunity. Life Sci 2024; 345:122612. [PMID: 38588949 DOI: 10.1016/j.lfs.2024.122612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 03/14/2024] [Accepted: 04/02/2024] [Indexed: 04/10/2024]
Abstract
Gut microbiota is a complex microbial community with the ability of maintaining intestinal health. Intestinal homeostasis largely depends on the mucosal immune system to defense external pathogens and promote tissue repair. In recent years, growing evidence revealed the importance of gut microbiota in shaping intestinal mucosal immunity. Therefore, according to the existing findings, this review first provided an overview of intestinal mucosal immune system before summarizing the regulatory roles of gut microbiota in intestinal innate and adaptive immunity. Specifically, this review delved into the gut microbial interactions with the cells such as intestinal epithelial cells (IECs), macrophages, dendritic cells (DCs), neutrophils, and innate lymphoid cells (ILCs) in innate immunity, and T and B lymphocytes in adaptive immunity. Furthermore, this review discussed the main effects of gut microbiota dysbiosis in intestinal diseases and offered future research prospects. The review highlighted the key regulatory roles of gut microbiota in intestinal mucosal immunity via various host-microbe interactions, providing valuable references for the development of microbial therapy in intestinal diseases.
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Affiliation(s)
- Jing Wang
- Department of Pharmacy, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China; Department of Pharmacy, North Sichuan Medical College, Nanchong 637000, China
| | - Mei He
- Department of Pharmacy, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China; Department of Pharmacy, North Sichuan Medical College, Nanchong 637000, China
| | - Ming Yang
- Department of Pharmacy, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China; Department of Pharmacy, North Sichuan Medical College, Nanchong 637000, China.
| | - Xiaopeng Ai
- Department of Pharmacy, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China; Department of Pharmacy, North Sichuan Medical College, Nanchong 637000, China.
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Lang Y, Wang Q, Sheng Q, Lu S, Yang M, Kong Z, Gao Y, Fan X, Shen N, Wang R, Lv Z. FTO-mediated m6A modification of serum amyloid A2 mRNA promotes podocyte injury and inflammation by activating the NF-κB signaling pathway. FASEB J 2024; 38:e23409. [PMID: 38193628 DOI: 10.1096/fj.202301419rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 12/17/2023] [Accepted: 12/21/2023] [Indexed: 01/10/2024]
Abstract
Diabetic kidney disease (DKD) is one of the severe complications of diabetes mellitus, yet there is no effective treatment. Exploring the development of DKD is essential to treatment. Podocyte injury and inflammation are closely related to the development of DKD. However, the mechanism of podocyte injury and progression in DKD remains largely unclear. Here, we observed that FTO expression was significantly upregulated in high glucose-induced podocytes and that overexpression of FTO promoted podocyte injury and inflammation. By performing RNA-seq and MeRIP-seq with control podocytes and high glucose-induced podocytes with or without FTO knockdown, we revealed that serum amyloid A2 (SAA2) is a target of FTO-mediated m6A modification. Knockdown of FTO markedly increased SAA2 mRNA m6A modification and decreased SAA2 mRNA expression. Mechanistically, we demonstrated that SAA2 might participate in podocyte injury and inflammation through activation of the NF-κB signaling pathway. Furthermore, by generating podocyte-specific adeno-associated virus 9 (AAV9) to knockdown SAA2 in mice, we discovered that the depletion of SAA2 significantly restored podocyte injury and inflammation. Together, our results suggested that upregulation of SAA2 promoted podocyte injury through m6A-dependent regulation, thus suggesting that SAA2 may be a therapeutic target for diabetic kidney disease.
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Affiliation(s)
- Yating Lang
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Qimeng Wang
- Department of Nephrology, Shandong Provincial Hospital, Shandong University, Jinan, China
| | - Qinghao Sheng
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Shangwei Lu
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Meilin Yang
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Zhijuan Kong
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Ying Gao
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Xiaoting Fan
- Department of Nephrology, Shandong Provincial Hospital, Shandong University, Jinan, China
| | - Ning Shen
- Department of Nephrology, Shandong Provincial Hospital, Shandong University, Jinan, China
| | - Rong Wang
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- Department of Nephrology, Shandong Provincial Hospital, Shandong University, Jinan, China
| | - Zhimei Lv
- Department of Nephrology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- Department of Nephrology, Shandong Provincial Hospital, Shandong University, Jinan, China
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Wang Q, Jia D, He J, Sun Y, Qian Y, Ge Q, Qi Y, Wang Q, Hu Y, Wang L, Fang Y, He H, Luo M, Feng L, Si J, Song Z, Wang L, Chen S. Lactobacillus Intestinalis Primes Epithelial Cells to Suppress Colitis-Related Th17 Response by Host-Microbe Retinoic Acid Biosynthesis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2303457. [PMID: 37983567 PMCID: PMC10754072 DOI: 10.1002/advs.202303457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 10/24/2023] [Indexed: 11/22/2023]
Abstract
Gut microbiome is integral to the pathogenesis of ulcerative colitis. A novel probiotic Lactobacillus intestinalis (L. intestinalis) exerts a protective effect against dextran sodium sulfate-induced colitis in mice. Based on flow cytometry, colitis-associated Th17 cells are the target of L. intestinalis, which is supported by the lack of protective effects of L. intestinalis in T cell-null Rag1-/- mice or upon anti-IL-17-A antibody-treated mice. Although L. intestinalis exerts no direct effect on T cell differentiation, it decreases C/EBPA-driven gut epithelial SAA1 and SAA2 production, which in turn impairs Th17 cell differentiation. Cometabolism of L. intestinalis ALDH and host ALDH1A2 contributed to elevated biosynthesis of retinoic acid (RA), which accounts for the anti-colitis effect in RAR-α -mediated way. In a cohort of ulcerative colitis patients, it is observed that fecal abundance of L. intestinalis is negatively associated with the C/EBPA-SAA1/2-Th17 axis. Finally, L. intestinalis has a synergistic effect with mesalazine in alleviating murine colitis. In conclusion, L. intestinalis and associated metabolites, RA, have potential therapeutic effects for suppressing colonic inflammation by modulating the crosstalk between intestinal epithelia and immunity.
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Affiliation(s)
- Qi‐Wen Wang
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Ding‐Jia‐Cheng Jia
- Department of GastroenterologySecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiang310058China
| | - Jia‐Min He
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Yong Sun
- Department of GastroenterologySecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiang310058China
| | - Yun Qian
- Department of Gastroenterology and HepatologyShenzhen University General HospitalShenzhenGuangdong518055China
| | - Qi‐Wei Ge
- Department of GastroenterologySecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiang310058China
| | - Ya‐Dong Qi
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Qing‐Yi Wang
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Ying‐Ying Hu
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Lan Wang
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Yan‐Fei Fang
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Hui‐Qin He
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Man Luo
- Department of NutritionSir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Li‐Jun Feng
- Department of NutritionSir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Jian‐Min Si
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
- Institution of GastroenterologyZhejiang UniversityHangzhouZhejiang310058China
- Prevention and Treatment Research Center of Senescent DiseaseZhejiang University School of MedicineHangzhouZhejiang310058China
| | - Zhang‐Fa Song
- Department of Colorectal SurgerySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
| | - Liang‐Jing Wang
- Department of GastroenterologySecond Affiliated Hospital of Zhejiang University School of MedicineHangzhouZhejiang310058China
- Institution of GastroenterologyZhejiang UniversityHangzhouZhejiang310058China
- Prevention and Treatment Research Center of Senescent DiseaseZhejiang University School of MedicineHangzhouZhejiang310058China
| | - Shu‐Jie Chen
- Department of GastroenterologySir Run Run Shaw HospitalZhejiang UniversityHangzhouZhejiang310058China
- Institution of GastroenterologyZhejiang UniversityHangzhouZhejiang310058China
- Prevention and Treatment Research Center of Senescent DiseaseZhejiang University School of MedicineHangzhouZhejiang310058China
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Colletti A, Pellizzato M, Cicero AF. The Possible Role of Probiotic Supplementation in Inflammation: A Narrative Review. Microorganisms 2023; 11:2160. [PMID: 37764004 PMCID: PMC10535592 DOI: 10.3390/microorganisms11092160] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/01/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
The fine balance between symbiotic and potentially opportunistic and/or pathogenic microorganisms can undergo quantitative alterations, which, when associated with low intestinal biodiversity, could be responsible for the development of gut inflammation and the so-called "intestinal dysbiosis". This condition is characterized by the disbalance of a fine synergistic mechanism involving the mucosal barrier, the intestinal neuroendocrine system, and the immune system that results in an acute inflammatory response induced by different causes, including viral or bacterial infections of the digestive tract. More frequently, however, dysbiosis is induced slowly and subtly by subliminal causal factors, resulting in a chronic condition related to different diseases affecting the digestive tract and other organs and apparatuses. Studies on animal models, together with studies on humans, highlight the significant role of the gut microbiota and microbiome in the occurrence of inflammatory conditions such as metabolic syndrome and cardiovascular diseases (CVDs); neurodegenerative, urologic, skin, liver, and kidney pathologies; and premature aging. The blood translocation of bacterial fragments has been found to be one of the processes linked to gut dysbiosis and responsible for the possible occurrence of "metabolic endotoxemia" and systemic inflammation, associated with an increased risk of oxidative stress and related diseases. In this context, supplementation with different probiotic strains has been shown to restore gut eubiosis, especially if administered in long-term treatments. The aim of this review is to describe the anti-inflammatory effects of specific probiotic strains observed in clinical trials and the respective indications, highlighting the differences in efficacy depending on strain, formulation, time and duration of treatment, and dosage used.
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Affiliation(s)
- Alessandro Colletti
- Department of Science and Drug Technology, University of Turin, 10124 Turin, Italy
- Italian Society of Nutraceutical Formulators (SIFNut), 31033 Treviso, Italy
| | - Marzia Pellizzato
- Italian Society of Nutraceutical Formulators (SIFNut), 31033 Treviso, Italy
| | - Arrigo Francesco Cicero
- Medical and Surgical Sciences Department, University of Bologna, 40126 Bologna, Italy;
- IRCCS AOUBO, 40138 Bologna, Italy
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Zhang C, Li Q, Xu Q, Dong W, Li C, Deng B, Gong J, Zhang LZ, Jin J. Pulmonary interleukin 1 beta/serum amyloid A3 axis promotes lung metastasis of hepatocellular carcinoma by facilitating the pre-metastatic niche formation. J Exp Clin Cancer Res 2023; 42:166. [PMID: 37443052 DOI: 10.1186/s13046-023-02748-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Increasing evidence suggests a vital role of the pre-metastatic niche in the formation of distant metastasis of many cancers. However, how the pre-metastatic niche is formed and promotes pulmonary metastasis of hepatocellular carcinoma (HCC) remains unknown. METHODS Orthotopic liver tumor models and RNA-Seq were used to identify dysregulated genes in the pre-metastatic lung. Il1b knockout (Il1b-/-) mice and lentivirus-mediated gene knockdown/overexpression were utilized to demonstrate the role of interleukin 1 beta (IL-1β)/serum amyloid A3 (SAA3) in the pre-metastatic niche formation and pulmonary metastasis. The potential molecular mechanisms were investigated by RNA-Seq, real-time quantitative PCR (qPCR), western blotting, immunohistochemistry (IHC), flow cytometry, luciferase reporter assay, double immunofluorescent staining and H&E staining. RESULTS Accumulation of myeloid cells and upregulation of IL-1β were observed in the pre-metastatic lung of orthotopic liver tumor models. Myeloid cells accumulation and pulmonary metastasis were suppressed in Il1b-/- mice and Il1r1-silencing mice. Mechanistically, SAA3 and matrix metallopeptidase 9 (MMP9) were identified as potential downstream targets of IL-1β. Overexpression of SAA3 in the lungs of Il1b-/- mice restored myeloid cells accumulation and pulmonary metastasis of the orthotopic HCC xenografts. Moreover, alveolar macrophages-derived IL-1β dramatically enhanced SAA3 expression in alveolar epithelial cells in an NF-κB dependent manner and increased MMP9 levels in an autocrine manner. Furthermore, SAA3 recruited myeloid cells to the lung without affecting the expression of MMP9 in myeloid cells. CONCLUSIONS Our study suggests a key role of pulmonary IL-1β and SAA3 in creating a permissive lung pre-metastatic niche by enhancing MMP9 expression and recruiting myeloid cells, respectively, thus promoting pulmonary metastasis of HCC.
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Affiliation(s)
- Chong Zhang
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Guangxi Health Commission Key Laboratory of Basic Research in Sphingolipid Metabolism Related Diseases, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Qing Li
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Guangxi Health Commission Key Laboratory of Basic Research in Sphingolipid Metabolism Related Diseases, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Qi Xu
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Wei Dong
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Chunmei Li
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Guangxi Health Commission Key Laboratory of Basic Research in Sphingolipid Metabolism Related Diseases, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Bin Deng
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Guangxi Health Commission Key Laboratory of Basic Research in Sphingolipid Metabolism Related Diseases, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
- China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Jiao Gong
- Department of Laboratory Medicine, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, Guangdong, China
| | - Li-Zhen Zhang
- Department of Urology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.
| | - Junfei Jin
- Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China.
- Guangxi Health Commission Key Laboratory of Basic Research in Sphingolipid Metabolism Related Diseases, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China.
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China.
- China-USA Lipids in Health and Disease Research Center, Guilin Medical University, Guilin, 541001, Guangxi, China.
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den Hartigh LJ, May KS, Zhang XS, Chait A, Blaser MJ. Serum amyloid A and metabolic disease: evidence for a critical role in chronic inflammatory conditions. Front Cardiovasc Med 2023; 10:1197432. [PMID: 37396595 PMCID: PMC10311072 DOI: 10.3389/fcvm.2023.1197432] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/15/2023] [Indexed: 07/04/2023] Open
Abstract
Serum amyloid A (SAA) subtypes 1-3 are well-described acute phase reactants that are elevated in acute inflammatory conditions such as infection, tissue injury, and trauma, while SAA4 is constitutively expressed. SAA subtypes also have been implicated as playing roles in chronic metabolic diseases including obesity, diabetes, and cardiovascular disease, and possibly in autoimmune diseases such as systemic lupus erythematosis, rheumatoid arthritis, and inflammatory bowel disease. Distinctions between the expression kinetics of SAA in acute inflammatory responses and chronic disease states suggest the potential for differentiating SAA functions. Although circulating SAA levels can rise up to 1,000-fold during an acute inflammatory event, elevations are more modest (∼5-fold) in chronic metabolic conditions. The majority of acute-phase SAA derives from the liver, while in chronic inflammatory conditions SAA also derives from adipose tissue, the intestine, and elsewhere. In this review, roles for SAA subtypes in chronic metabolic disease states are contrasted to current knowledge about acute phase SAA. Investigations show distinct differences between SAA expression and function in human and animal models of metabolic disease, as well as sexual dimorphism of SAA subtype responses.
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Affiliation(s)
- Laura J. den Hartigh
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Karolline S. May
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Xue-Song Zhang
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, United States
| | - Alan Chait
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Martin J. Blaser
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, United States
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Song C, Chai Z, Chen S, Zhang H, Zhang X, Zhou Y. Intestinal mucus components and secretion mechanisms: what we do and do not know. Exp Mol Med 2023; 55:681-691. [PMID: 37009791 PMCID: PMC10167328 DOI: 10.1038/s12276-023-00960-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/26/2022] [Indexed: 04/04/2023] Open
Abstract
Damage to the colon mucus barrier, the first line of defense against microorganisms, is an important determinant of intestinal diseases such as inflammatory bowel disease and colorectal cancer, and disorder in extraintestinal organs. The mucus layer has attracted the attention of the scientific community in recent years, and with the discovery of new mucosal components, it has become increasingly clear that the mucosal barrier is a complex system composed of many components. Moreover, certain components are jointly involved in regulating the structure and function of the mucus barrier. Therefore, a comprehensive and systematic understanding of the functional components of the mucus layer is clearly warranted. In this review, we summarize the various functional components of the mucus layer identified thus far and describe their unique roles in shaping mucosal structure and function. Furthermore, we detail the mechanisms underlying mucus secretion, including baseline and stimulated secretion. In our opinion, baseline secretion can be categorized into spontaneous Ca2+ oscillation-mediated slow and continuous secretion and stimulated secretion, which is mediated by massive Ca2+ influx induced by exogenous stimuli. This review extends the current understanding of the intestinal mucus barrier, with an emphasis on host defense strategies based on fortification of the mucus layer.
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Affiliation(s)
- Chunyan Song
- Department of Preventive Medicine, Health Science Center, Ningbo University, Zhejiang Key Laboratory of Pathophysiology, Ningbo, Zhejiang, 315211, China
| | - Zhenglong Chai
- Department of Preventive Medicine, Health Science Center, Ningbo University, Zhejiang Key Laboratory of Pathophysiology, Ningbo, Zhejiang, 315211, China
| | - Si Chen
- Department of Preventive Medicine, Health Science Center, Ningbo University, Zhejiang Key Laboratory of Pathophysiology, Ningbo, Zhejiang, 315211, China
| | - Hui Zhang
- Department of Preventive Medicine, Health Science Center, Ningbo University, Zhejiang Key Laboratory of Pathophysiology, Ningbo, Zhejiang, 315211, China
| | - Xiaohong Zhang
- Department of Preventive Medicine, Health Science Center, Ningbo University, Zhejiang Key Laboratory of Pathophysiology, Ningbo, Zhejiang, 315211, China.
- The Affiliated Hospital of Medical School, Ningbo University, Institute of Digestive Disease of Ningbo University, Ningbo, Zhejiang, 315020, China.
| | - Yuping Zhou
- The Affiliated Hospital of Medical School, Ningbo University, Institute of Digestive Disease of Ningbo University, Ningbo, Zhejiang, 315020, China.
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Jiang Q, Sherlock DN, Elolimy AA, Vailati-Riboni M, Yoon I, Loor JJ. Impact of a Saccharomyces cerevisiae fermentation product during an intestinal barrier challenge in lactating Holstein cows on ileal microbiota and markers of tissue structure and immunity. J Anim Sci 2023; 101:skad309. [PMID: 37721866 PMCID: PMC10630188 DOI: 10.1093/jas/skad309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 09/16/2023] [Indexed: 09/20/2023] Open
Abstract
Feeding a Saccharomyces cerevisiae fermentation product (SCFP; NutriTek, Diamond V, Cedar Rapids, IA) during periods of metabolic stress is beneficial to the health of dairy cows partially through its effect on the gut microbiota. Whether SCFP alters the ileal microbiota in lactating cows during intestinal challenges induced by feed restriction (FR) is not known. We used 16S rRNA sequencing to assess if feeding SCFP during FR to induce gut barrier dysfunction alters microbiota profiles in the ileum. The mRNA abundance of key genes associated with tissue structures and immunity was also detected. Multiparous cows (97.1 ± 7.6 days in milk (DIM); n = 7 per treatment) fed a control diet or the control plus 19 g/d NutriTek for 9 wk were subjected to an FR challenge for 5 d, during which they were fed 40% of their ad libitum intake from the 7 d before FR. All cows were slaughtered at the end of FR. DNA extracted from ileal digesta was subjected to PacBio Full-Length 16S rRNA gene sequencing. High-quality amplicon sequence analyses were performed with Targeted Amplicon Diversity Analysis and MicrobiomeAnalyst. Functional analysis was performed and analyzed using PICRUSt and STAMP. Feeding SCFP did not (P > 0.05) alter dry matter intake, milk yield, or milk components during FR. In addition, SCFP supplementation tended (P = 0.07) to increase the relative abundance of Proteobacteria and Bifidobacterium animalis. Compared with controls, feeding SCFP increased the relative abundance of Lactobacillales (P = 0.03). Gluconokinase, oligosaccharide reducing-end xylanase, and 3-hydroxy acid dehydrogenase were among the enzymes overrepresented (P < 0.05) in response to feeding SCFP. Cows fed SCFP had a lower representation of adenosylcobalamin biosynthesis I (early cobalt insertion) and pyrimidine deoxyribonucleotides de novo biosynthesis III (P < 0.05). Subsets of the Firmicutes genus, Bacteroidota phylum, and Treponema genus were correlated with the mRNA abundance of genes associated with ileal integrity (GCNT3, GALNT5, B3GNT3, FN1, ITGA2, LAMB2) and inflammation (AOX1, GPX8, CXCL12, CXCL14, CCL4, SAA3). Our data indicated that the moderate FR induced dysfunction of the ileal microbiome, but feeding SCFP increased the abundance of some beneficial gut probiotic bacteria and other species related to tissue structures and immunity.
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Affiliation(s)
- Qianming Jiang
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Danielle N Sherlock
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Ahmed A Elolimy
- Animal Production Department, National Research Center, Dokki, Giza 12622, Egypt
| | | | | | - Juan J Loor
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA
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10
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Gomes AC, Sousa DM, Oliveira TC, Fonseca Ó, Pinto RJ, Silvério D, Fernandes AI, Moreira AC, Silva T, Teles MJ, Pereira L, Saraiva M, Lamghari M, Gomes MS. Serum amyloid A proteins reduce bone mass during mycobacterial infections. Front Immunol 2023; 14:1168607. [PMID: 37153579 PMCID: PMC10161249 DOI: 10.3389/fimmu.2023.1168607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/11/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction Osteopenia has been associated to several inflammatory conditions, including mycobacterial infections. How mycobacteria cause bone loss remains elusive, but direct bone infection may not be required. Methods Genetically engineered mice and morphometric, transcriptomic, and functional analyses were used. Additionally, inflammatory mediators and bone turnover markers were measured in the serum of healthy controls, individuals with latent tuberculosis and patients with active tuberculosis. Results and discussion We found that infection with Mycobacterium avium impacts bone turnover by decreasing bone formation and increasing bone resorption, in an IFNγ- and TNFα-dependent manner. IFNγ produced during infection enhanced macrophage TNFα secretion, which in turn increased the production of serum amyloid A (SAA) 3. Saa3 expression was upregulated in the bone of both M. avium- and M. tuberculosis-infected mice and SAA1 and 2 proteins (that share a high homology with murine SAA3 protein) were increased in the serum of patients with active tuberculosis. Furthermore, the increased SAA levels seen in active tuberculosis patients correlated with altered serum bone turnover markers. Additionally, human SAA proteins impaired bone matrix deposition and increased osteoclastogenesis in vitro. Overall, we report a novel crosstalk between the cytokine-SAA network operating in macrophages and bone homeostasis. These findings contribute to a better understanding of the mechanisms of bone loss during infection and open the way to pharmacological intervention. Additionally, our data and disclose SAA proteins as potential biomarkers of bone loss during infection by mycobacteria.
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Affiliation(s)
- Ana Cordeiro Gomes
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IMBC – Instituto de Biologia Molecular e Celular, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
- *Correspondence: Ana Cordeiro Gomes,
| | - Daniela Monteiro Sousa
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- INEB – Instituto Nacional de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
| | | | - Óscar Fonseca
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Mestrado em Bioquímica Clínica, Universidade de Aveiro, , Aveiro, Portugal
| | - Ricardo J. Pinto
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
- IPATIMUP – Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto, Portugal
| | - Diogo Silvério
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IMBC – Instituto de Biologia Molecular e Celular, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Ana Isabel Fernandes
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IMBC – Instituto de Biologia Molecular e Celular, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Ana C. Moreira
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IMBC – Instituto de Biologia Molecular e Celular, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Tânia Silva
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Maria José Teles
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- CHUSJ – Centro Hospitalar de São João, Porto, Portugal
- EPIUnit, ISPUP - Instituto de Saúde Pública da Universidade do Porto, Porto, Portugal
| | - Luísa Pereira
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP – Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto, Portugal
| | - Margarida Saraiva
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IMBC – Instituto de Biologia Molecular e Celular, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Meriem Lamghari
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- INEB – Instituto Nacional de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Maria Salomé Gomes
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
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11
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Ardalan M, Ahmadian E, Hosseiniyan Khatibi SM, Rahbar Saadat Y, Bastami M, Bagheri Y, Zununi Vahed F, Shoja MM, Zununi Vahed S. Microbiota and glomerulonephritis: An immunological point of view. Am J Med Sci 2022; 364:695-705. [PMID: 35870511 DOI: 10.1016/j.amjms.2022.05.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 03/26/2022] [Accepted: 05/05/2022] [Indexed: 01/25/2023]
Abstract
Glomerular injury is the major cause of chronic kidney diseases (CKD) worldwide and is characterized by proteinuria. Glomerulonephritis (GN) has a wide spectrum of etiologies, the intensity of glomerular damage, histopathology, and clinical outcomes that can be associated with the landscape of the nephritogenic immune response. Beyond impaired immune responses and genetic factors, recent evidence indicates that microbiota can be contributed to the pathogenesis of GN and patients' outcomes by impacting many aspects of the innate and adaptive immune systems. It is still unknown whether dysbiosis induces GN or it is a secondary effect of the disease. Several factors such as drugs and nutritional problems can lead to dysbiosis in GN patients. It has been postulated that gut dysbiosis activates immune responses, promotes a state of systemic inflammation, and produces uremic toxins contributing to kidney tissue inflammation, apoptosis, and subsequent proteinuric nephropathy. In this review, the impact of gastrointestinal tract (GI) microbiota on the pathogenesis of the primary GN will be highlighted. The application of therapeutic interventions based on the manipulation of gut microbiota with special diets and probiotic supplementation can be effective in GN.
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Affiliation(s)
| | - Elham Ahmadian
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | - Milad Bastami
- Non-communicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Yasin Bagheri
- Kidney Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mohammadali M Shoja
- Clinical Academy of Teaching and Learning, Ross University School of Medicine, Miramar, FL, USA
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12
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Yan J, Zhao J, Ning X, Qin Y, Xing Y, Wang Y, Jia Q, Huang B, Ma R, Lei C, Zhou M, Yu Z, Zhang Y, Guo WF, Sun S. Alterations of the gut microbiota in patients with immunoglobulin light chain amyloidosis. Front Immunol 2022; 13:973760. [PMID: 36341382 PMCID: PMC9628213 DOI: 10.3389/fimmu.2022.973760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/28/2022] [Indexed: 11/13/2022] Open
Abstract
Background Emerging evidence revealed that gut microbial dysbiosis is implicated in the development of plasma cell dyscrasias and amyloid deposition diseases, but no data are available on the relationship between gut microbiota and immunoglobulin light chain (AL) amyloidosis. Methods To characterize the gut microbiota in patients with AL amyloidosis, we collected fecal samples from patients with AL amyloidosis (n=27) and age-, gender-, and BMI-matched healthy controls (n=27), and conducted 16S rRNA MiSeq sequencing and amplicon sequence variants (ASV)-based analysis. Results There were significant differences in gut microbial communities between the two groups. At the phylum level, the abundance of Actinobacteriota and Verrucomicrobiota was significantly higher, while Bacteroidota reduced remarkably in patients with AL amyloidosis. At the genus level, 17 genera, including Bifidobacterium, Akkermansia, and Streptococcus were enriched, while only 4 genera including Faecalibacterium, Tyzzerella, Pseudomonas, and Anaerostignum decreased evidently in patients with AL amyloidosis. Notably, 5 optimal ASV-based microbial markers were identified as the diagnostic model of AL amyloidosis and the AUC value of the train set and the test set was 0.8549 (95% CI 0.7310-0.9789) and 0.8025 (95% CI 0.5771-1), respectively. With a median follow-up of 19.0 months, further subgroup analysis also demonstrated some key gut microbial markers were related to disease severity, treatment response, and even prognosis of patients with AL amyloidosis. Conclusions For the first time, we demonstrated the alterations of gut microbiota in AL amyloidosis and successfully established and validated the microbial-based diagnostic model, which boosted more studies about microbe-based strategies for diagnosis and treatment in patients with AL amyloidosis in the future.
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Affiliation(s)
- Jipeng Yan
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Jin Zhao
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Xiaoxuan Ning
- Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi’an, China
- *Correspondence: Shiren Sun, ; Xiaoxuan Ning,
| | - Yunlong Qin
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Yan Xing
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Yuwei Wang
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Qing Jia
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Boyong Huang
- Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Rui Ma
- Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Changhui Lei
- Xijing Hypertrophic Cardiomyopathy Center, Department of Ultrasound, Xijing Hospital, Xi’an, China
| | - Meilan Zhou
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Zixian Yu
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Yumeng Zhang
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Wei-Feng Guo
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Shiren Sun
- Department of Nephrology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
- *Correspondence: Shiren Sun, ; Xiaoxuan Ning,
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13
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Valdes J, Gagné-Sansfaçon J, Reyes V, Armas A, Marrero G, Moyo-Muamba M, Ramanathan S, Perreault N, Ilangumaran S, Rivard N, Fortier LC, Menendez A. Defects in the expression of colonic host defense factors associate with barrier dysfunction induced by a high-fat/high-cholesterol diet. Anat Rec (Hoboken) 2022; 306:1165-1183. [PMID: 36196983 DOI: 10.1002/ar.25083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 08/25/2022] [Accepted: 09/11/2022] [Indexed: 11/07/2022]
Abstract
The effect of Western diets in the gastrointestinal system is largely mediated by their ability to promote alterations in the immunity and physiology of the intestinal epithelium, and to affect the composition of the commensal microbiota. To investigate the response of the colonic epithelium to high-fat/high-cholesterol diets (HFHCDs), we evaluated the synthesis of host defense factors involved in the maintenance of the colonic homeostasis. C57BL/6 mice were fed an HFHCD for 3 weeks and their colons were evaluated for histopathology, gene expression, and microbiota composition. In addition, intestinal permeability and susceptibility to Citrobacter rodentium were also studied. HFHCD caused colonic hyperplasia, loss of goblet cells, thinning of the mucus layer, moderate changes in the composition of the intestinal microbiota, and an increase in intestinal permeability. Gene expression analyses revealed significant drops in the transcript levels of Muc1, Muc2, Agr2, Atoh1, Spdef, Ang4, Camp, Tff3, Dmbt1, Fcgbp, Saa3, and Retnlb. The goblet cell granules of HFHCD-fed mice were devoid of Relmβ and Tff3, indicating defective production of those two factors critical for intestinal epithelial defense and homeostasis. In correspondence with these defects, colonic bacteria were in close contact with, and invading the epithelium. Fecal shedding of C. rodentium showed an increased bacterial burden in HFHCD-fed animals accompanied by increased epithelial damage. Collectively, our results show that HFHCD perturbs the synthesis of colonic host defense factors, which associate with alterations in the commensal microbiota, the integrity of the intestinal barrier, and the host's susceptibility to enteric infections.
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Affiliation(s)
- Jennifer Valdes
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Jessica Gagné-Sansfaçon
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Vilcy Reyes
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Anny Armas
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Gisela Marrero
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Mitterrand Moyo-Muamba
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Sheela Ramanathan
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Nathalie Perreault
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Subburaj Ilangumaran
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Nathalie Rivard
- Department of Immunology and Cell Biology, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Louis-Charles Fortier
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Alfredo Menendez
- Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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14
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Peetsalu K, Niine T, Loch M, Dorbek-Kolin E, Tummeleht L, Orro T. Effect of colostrum on the acute-phase response in neonatal dairy calves. J Dairy Sci 2022; 105:6207-6219. [DOI: 10.3168/jds.2021-21562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/11/2022] [Indexed: 12/29/2022]
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15
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Yaker L, Tebani A, Lesueur C, Dias C, Jung V, Bekri S, Guerrera IC, Kamel S, Ausseil J, Boullier A. Extracellular Vesicles From LPS-Treated Macrophages Aggravate Smooth Muscle Cell Calcification by Propagating Inflammation and Oxidative Stress. Front Cell Dev Biol 2022; 10:823450. [PMID: 35356285 PMCID: PMC8959646 DOI: 10.3389/fcell.2022.823450] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 02/09/2022] [Indexed: 12/29/2022] Open
Abstract
Background: Vascular calcification (VC) is a cardiovascular complication associated with a high mortality rate among patients with diseases such as atherosclerosis and chronic kidney disease. During VC, vascular smooth muscle cells (VSMCs) undergo an osteogenic switch and secrete a heterogeneous population of extracellular vesicles (EVs). Recent studies have shown involvement of EVs in the inflammation and oxidative stress observed in VC. We aimed to decipher the role and mechanism of action of macrophage-derived EVs in the propagation of inflammation and oxidative stress on VSMCs during VC. Methods: The macrophage murine cell line RAW 264.7 treated with lipopolysaccharide (LPS-EK) was used as a cellular model for inflammatory and oxidative stress. EVs secreted by these macrophages were collected by ultracentrifugation and characterized by transmission electron microscopy, cryo-electron microscopy, nanoparticle tracking analysis, and the analysis of acetylcholinesterase activity, as well as that of CD9 and CD81 protein expression by western blotting. These EVs were added to a murine VSMC cell line (MOVAS-1) under calcifying conditions (4 mM Pi—7 or 14 days) and calcification assessed by the o-cresolphthalein calcium assay. EV protein content was analyzed in a proteomic study and EV cytokine content assessed using an MSD multiplex immunoassay. Results: LPS-EK significantly decreased macrophage EV biogenesis. A 24-h treatment of VSMCs with these EVs induced both inflammatory and oxidative responses. LPS-EK-treated macrophage-derived EVs were enriched for pro-inflammatory cytokines and CAD, PAI-1, and Saa3 proteins, three molecules involved in inflammation, oxidative stress, and VC. Under calcifying conditions, these EVs significantly increase the calcification of VSMCs by increasing osteogenic markers and decreasing contractile marker expression. Conclusion: Our results show that EVs derived from LPS-EK–treated-macrophages are able to induce pro-inflammatory and pro-oxidative responses in surrounding cells, such as VSMCs, thus aggravating the VC process.
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Affiliation(s)
- Linda Yaker
- MP3CV-UR7517, CURS-University of Picardie Jules Verne, Amiens, France
| | - Abdellah Tebani
- INSERM U1245, CHU Rouen, Normandie University, UNIROUEN, Rouen, France
- Department of Metabolic Biochemistry, Rouen University Hospital, Rouen, France
| | - Céline Lesueur
- INSERM U1245, CHU Rouen, Normandie University, UNIROUEN, Rouen, France
| | - Chloé Dias
- Infinity, INSERM UMR1291, CNRS UMR5051, University of Toulouse III, Toulouse, France
| | - Vincent Jung
- INSERM US24/CNRS UAR3633, Proteomic Platform Necker, University of Paris—Federative Research Structure Necker, Paris, France
| | - Soumeya Bekri
- INSERM U1245, CHU Rouen, Normandie University, UNIROUEN, Rouen, France
- Department of Metabolic Biochemistry, Rouen University Hospital, Rouen, France
| | - Ida Chiara Guerrera
- INSERM US24/CNRS UAR3633, Proteomic Platform Necker, University of Paris—Federative Research Structure Necker, Paris, France
| | - Saïd Kamel
- MP3CV-UR7517, CURS-University of Picardie Jules Verne, Amiens, France
- Laboratory of Biochemistry, CHU Amiens-Picardie, Amiens, France
| | - Jérôme Ausseil
- Infinity, INSERM UMR1291, CNRS UMR5051, University of Toulouse III, Toulouse, France
- Service de Biochimie, Institut Fédératif de Biologie, CHU Toulouse, Toulouse, France
| | - Agnès Boullier
- MP3CV-UR7517, CURS-University of Picardie Jules Verne, Amiens, France
- Laboratory of Biochemistry, CHU Amiens-Picardie, Amiens, France
- *Correspondence: Agnès Boullier,
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16
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Kim J, Shin JW, Lee H, Kim JH, Choi SM, Lee C, Kang HR, Park SH, Bae Y, Chung DH, Kim HY. Serum amyloid A promotes emphysema by triggering the reciprocal activation of neutrophils and ILC3s. Clin Transl Med 2021; 11:e637. [PMID: 34923771 PMCID: PMC8684768 DOI: 10.1002/ctm2.637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/08/2022] Open
Affiliation(s)
- Jihyun Kim
- Laboratory of Mucosal Immunology Department of Biomedical Sciences Seoul National University College of Medicine Seoul South Korea
- Seoul National University Medical Research Center Institute of Allergy and Clinical Immunology Seoul South Korea
| | - Jae Woo Shin
- Laboratory of Mucosal Immunology Department of Biomedical Sciences Seoul National University College of Medicine Seoul South Korea
| | - Hyun‐Jun Lee
- Natural Medicine Research Center Korea Research Institute of Bioscience and Biotechnology (KRIBB) Cheongju Chungbuk South Korea
| | - Ji Hyung Kim
- College of Life Sciences and Biotechnology Korea University Seoul South Korea
| | - Sun Mi Choi
- Department of Internal Medicine Seoul National University Hospital Seoul South Korea
| | - Chang‐Hoon Lee
- Department of Internal Medicine Seoul National University Hospital Seoul South Korea
| | - Hye Ryun Kang
- Seoul National University Medical Research Center Institute of Allergy and Clinical Immunology Seoul South Korea
- Department of Internal Medicine Seoul National University Hospital Seoul South Korea
| | - Seok Hee Park
- Department of Biological Sciences Sungkyunkwan University Suwon South Korea
- Samsung Advanced Institute for Health Sciences and Technology Sungkyunkwan University Seoul Korea
| | - Yoe‐Sik Bae
- Department of Biological Sciences Sungkyunkwan University Suwon South Korea
- Samsung Advanced Institute for Health Sciences and Technology Sungkyunkwan University Seoul Korea
| | - Doo Hyun Chung
- Department of Pathology Seoul National University College of Medicine Seoul South Korea
- Laboratory of Immune Regulation Department of Biomedical Sciences Seoul National University College of Medicine Seoul South Korea
| | - Hye Young Kim
- Laboratory of Mucosal Immunology Department of Biomedical Sciences Seoul National University College of Medicine Seoul South Korea
- Seoul National University Medical Research Center Institute of Allergy and Clinical Immunology Seoul South Korea
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17
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Shridas P, Patrick AC, Tannock LR. Role of Serum Amyloid A in Abdominal Aortic Aneurysm and Related Cardiovascular Diseases. Biomolecules 2021; 11:biom11121883. [PMID: 34944527 PMCID: PMC8699432 DOI: 10.3390/biom11121883] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/07/2021] [Accepted: 12/13/2021] [Indexed: 01/02/2023] Open
Abstract
Epidemiological data positively correlate plasma serum amyloid A (SAA) levels with cardiovascular disease severity and mortality. Studies by several investigators have indicated a causal role for SAA in the development of atherosclerosis in animal models. Suppression of SAA attenuates the development of angiotensin II (AngII)-induced abdominal aortic aneurysm (AAA) formation in mice. Thus, SAA is not just a marker for cardiovascular disease (CVD) development, but it is a key player. However, to consider SAA as a therapeutic target for these diseases, the pathway leading to its involvement needs to be understood. This review provides a brief description of the pathobiological significance of this enigmatic molecule. The purpose of this review is to summarize the data relevant to its role in the development of CVD, the pitfalls in SAA research, and unanswered questions in the field.
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Affiliation(s)
- Preetha Shridas
- Department of Internal Medicine, University of Kentucky, Lexington, KY 40536, USA
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY 40536, USA
- Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY 40536, USA
| | - Avery C Patrick
- Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Lisa R Tannock
- Department of Internal Medicine, University of Kentucky, Lexington, KY 40536, USA
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY 40536, USA
- Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY 40536, USA
- Veterans Affairs Lexington, University of Kentucky, Lexington, KY 40536, USA
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18
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Bang YJ, Hu Z, Li Y, Gattu S, Ruhn KA, Raj P, Herz J, Hooper LV. Serum amyloid A delivers retinol to intestinal myeloid cells to promote adaptive immunity. Science 2021; 373:eabf9232. [PMID: 34529485 DOI: 10.1126/science.abf9232] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Ye-Ji Bang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Zehan Hu
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yun Li
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sureka Gattu
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kelly A Ruhn
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Prithvi Raj
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Lora V Hooper
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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19
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Davis TA, Conradie D, Shridas P, de Beer FC, Engelbrecht AM, de Villiers WJS. Serum Amyloid A Promotes Inflammation-Associated Damage and Tumorigenesis in a Mouse Model of Colitis-Associated Cancer. Cell Mol Gastroenterol Hepatol 2021; 12:1329-1341. [PMID: 34217896 PMCID: PMC8463861 DOI: 10.1016/j.jcmgh.2021.06.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/20/2021] [Accepted: 06/21/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS Identifying new approaches to lessen inflammation, as well as the associated malignant consequences, remains crucial to improving the lives and prognosis of patients diagnosed with inflammatory bowel diseases. Although it previously has been suggested as a suitable biomarker for monitoring disease activity in patients diagnosed with Crohn's disease, the role of the acute-phase protein serum amyloid A (SAA) in inflammatory bowel disease remains unclear. In this study, we aimed to assess the role of SAA in colitis-associated cancer. METHODS We established a model of colitis-associated cancer in wild-type and SAA double-knockout (Saa1/2-/-) mice by following the azoxymethane/dextran sulfate sodium protocol. Disease activity was monitored throughout the study while colon and tumor tissues were harvested for subsequent use in cytokine analyses, Western blot, and immunohistochemistry +experiments. RESULTS We observed attenuated disease activity in mice deficient for Saa1/2 as evidenced by decreased weight loss, increased stool consistency, decreased rectal bleeding, and decreased colitis-associated tissue damage. Macrophage infiltration, including CD206+ M2-like macrophages, also was attenuated in SAA knockout mice, while levels of interleukin 4, interleukin 10, and tumor necrosis factor-ɑ were decreased in the distal colon. Mice deficient for SAA also showed a decreased tumor burden, and tumors were found to have increased apoptotic activity coupled with decreased expression for markers of proliferation. CONCLUSION Based on these findings, we conclude that SAA has an active role in inflammatory bowel disease and that it could serve as a therapeutic target aimed at decreasing chronic inflammation and the associated risk of developing colitis-associated cancer.
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Affiliation(s)
| | | | - Preetha Shridas
- Department of Internal Medicine, University of Kentucky, Lexington, Kentucky
| | - Frederick C de Beer
- Department of Internal Medicine, University of Kentucky, Lexington, Kentucky
| | - Anna-Mart Engelbrecht
- Department of Physiological Sciences; African Cancer Institute, Department of Global Health
| | - Willem J S de Villiers
- African Cancer Institute, Department of Global Health; Department of Internal Medicine, Stellenbosch University, Stellenbosch, South Africa.
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20
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Klooster JPT, Bol-Schoenmakers M, van Summeren K, van Vliet ALW, de Haan CAM, van Kuppeveld FJM, Verkoeijen S, Pieters R. Enterocytes, fibroblasts and myeloid cells synergize in anti-bacterial and anti-viral pathways with IL22 as the central cytokine. Commun Biol 2021; 4:631. [PMID: 34045640 PMCID: PMC8160143 DOI: 10.1038/s42003-021-02176-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 05/03/2021] [Indexed: 12/30/2022] Open
Abstract
IL22 is an important cytokine involved in the intestinal defense mechanisms against microbiome. By using ileum-derived organoids, we show that the expression of anti-microbial peptides (AMPs) and anti-viral peptides (AVPs) can be induced by IL22. In addition, we identified a bacterial and a viral route, both leading to IL22 production by T cells, but via different pathways. Bacterial products, such as LPS, induce enterocyte-secreted SAA1, which triggers the secretion of IL6 in fibroblasts, and subsequently IL22 in T cells. This IL22 induction can then be enhanced by macrophage-derived TNFα in two ways: by enhancing the responsiveness of T cells to IL6 and by increasing the expression of IL6 by fibroblasts. Viral infections of intestinal cells induce IFNβ1 and subsequently IL7. IFNβ1 can induce the expression of IL6 in fibroblasts and the combined activity of IL6 and IL7 can then induce IL22 expression in T cells. We also show that IL22 reduces the expression of viral entry receptors (e.g. ACE2, TMPRSS2, DPP4, CD46 and TNFRSF14), increases the expression of anti-viral proteins (e.g. RSAD2, AOS, ISG20 and Mx1) and, consequently, reduces the viral infection of neighboring cells. Overall, our data indicates that IL22 contributes to the innate responses against both bacteria and viruses.
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Affiliation(s)
- Jean Paul Ten Klooster
- Research Centre Healthy and Sustainable Living, Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, Utrecht, The Netherlands.
| | - Marianne Bol-Schoenmakers
- Institute for Risk Assessment Sciences, Population Health Sciences Division, Utrecht University, Utrecht, The Netherlands
| | - Kitty van Summeren
- Research Centre Healthy and Sustainable Living, Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, Utrecht, The Netherlands
| | - Arno L W van Vliet
- Virology Section, Infectious Disease and Immunology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Cornelis A M de Haan
- Virology Section, Infectious Disease and Immunology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Frank J M van Kuppeveld
- Virology Section, Infectious Disease and Immunology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Saertje Verkoeijen
- Research Centre Healthy and Sustainable Living, Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, Utrecht, The Netherlands
| | - Raymond Pieters
- Research Centre Healthy and Sustainable Living, Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, Utrecht, The Netherlands
- Institute for Risk Assessment Sciences, Population Health Sciences Division, Utrecht University, Utrecht, The Netherlands
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21
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Kamiya S, Shimizu K, Okada A, Inoshima Y. Induction of Serum Amyloid A3 in Mouse Mammary Epithelial Cells Stimulated with Lipopolysaccharide and Lipoteichoic Acid. Animals (Basel) 2021; 11:ani11061548. [PMID: 34070499 PMCID: PMC8230092 DOI: 10.3390/ani11061548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/15/2021] [Accepted: 05/23/2021] [Indexed: 12/04/2022] Open
Abstract
Simple Summary Serum amyloid A (SAA) is an acute phase protein present in mammals and birds. Based on the amino acid sequence, SAA has been classified into isoforms SAA1–4 in mice. Previously, it was reported that after the stimulation with bacterial antigens, the expression of the Saa3 mRNA was induced more strongly than that of the Saa1 mRNA in mouse epithelia, including colonic and alveolar epithelial cells, indicating that SAA3 plays a role in the local response. However, the contribution of SAA3 to the local response in mouse mammary epithelium, where mastitis occurs due to bacterial infection, has not been completely determined yet. In this study, to clarify whether mouse SAA3 has a role in the defense against bacterial infection in mouse mammary epithelium, normal murine mammary gland (NMuMG) epithelial cells were stimulated with lipopolysaccharide (LPS) and lipoteichoic acid (LTA). LPS and LTA significantly enhanced mRNA expression level of the Saa3 gene but not that of Saa1. Furthermore, LPS induced SAA3 protein expression more strongly than LTA. Our data indicate that SAA3 expression in mouse mammary epithelial cells was increased by the stimulation with bacterial antigens, suggesting that SAA3 is involved in the defense against bacterial infection in mouse mammary epithelium. Abstract In this study, to establish whether serum amyloid A (SAA) 3 plays a role in the defense against bacterial infection in mouse mammary epithelium, normal murine mammary gland (NMuMG) epithelial cells were stimulated with lipopolysaccharide (LPS) and lipoteichoic acid (LTA). LPS and LTA significantly enhanced mRNA expression level of the Saa3 gene, whereas no significant change was observed in the Saa1 mRNA level. Furthermore, LPS induced SAA3 protein expression more strongly than LTA, whereas neither LPS nor LTA significantly affected SAA1 protein expression. These data indicate that the expression of SAA3 in mouse mammary epithelial cells was increased by the stimulation with bacterial antigens. SAA3 has been reported to stimulate neutrophils in the intestinal epithelium and increase interleukin-22 expression, which induces activation of the innate immune system and production of antibacterial proteins, such as antimicrobial peptides. Therefore, collectively, these data suggest that SAA3 is involved in the defense against bacterial infection in mouse mammary epithelium.
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Affiliation(s)
- Sato Kamiya
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan; (S.K.); (K.S.); (A.O.)
| | - Kaori Shimizu
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan; (S.K.); (K.S.); (A.O.)
| | - Ayaka Okada
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan; (S.K.); (K.S.); (A.O.)
- Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan; (S.K.); (K.S.); (A.O.)
- Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan
- Joint Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
- Correspondence: ; Tel.: +81-58-293-2863
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22
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Armstrong AJS, Quinn K, Fouquier J, Li SX, Schneider JM, Nusbacher NM, Doenges KA, Fiorillo S, Marden TJ, Higgins J, Reisdorph N, Campbell TB, Palmer BE, Lozupone CA. Systems Analysis of Gut Microbiome Influence on Metabolic Disease in HIV-Positive and High-Risk Populations. mSystems 2021; 6:e01178-20. [PMID: 34006628 PMCID: PMC8269254 DOI: 10.1128/msystems.01178-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 04/15/2021] [Indexed: 12/20/2022] Open
Abstract
Poor metabolic health, characterized by insulin resistance and dyslipidemia, is higher in people living with HIV and has been linked with inflammation, antiretroviral therapy (ART) drugs, and ART-associated lipodystrophy (LD). Metabolic disease is associated with gut microbiome composition outside the context of HIV but has not been deeply explored in HIV infection or in high-risk men who have sex with men (HR-MSM), who have a highly altered gut microbiome composition. Furthermore, the contribution of increased bacterial translocation and associated systemic inflammation that has been described in HIV-positive and HR-MSM individuals has not been explored. We used a multiomic approach to explore relationships between impaired metabolic health, defined using fasting blood markers, gut microbes, immune phenotypes, and diet. Our cohort included ART-treated HIV-positive MSM with or without LD, untreated HIV-positive MSM, and HR-MSM. For HIV-positive MSM on ART, we further explored associations with the plasma metabolome. We found that elevated plasma lipopolysaccharide binding protein (LBP) was the most important predictor of impaired metabolic health and network analysis showed that LBP formed a hub joining correlated microbial and immune predictors of metabolic disease. Taken together, our results suggest the role of inflammatory processes linked with bacterial translocation and interaction with the gut microbiome in metabolic disease among HIV-positive and -negative MSM.IMPORTANCE The gut microbiome in people living with HIV (PLWH) is of interest since chronic infection often results in long-term comorbidities. Metabolic disease is prevalent in PLWH even in well-controlled infection and has been linked with the gut microbiome in previous studies, but little attention has been given to PLWH. Furthermore, integrated analyses that consider gut microbiome, together with diet, systemic immune activation, metabolites, and demographics, have been lacking. In a systems-level analysis of predictors of metabolic disease in PLWH and men who are at high risk of acquiring HIV, we found that increased lipopolysaccharide-binding protein, an inflammatory marker indicative of compromised intestinal barrier function, was associated with worse metabolic health. We also found impaired metabolic health associated with specific dietary components, gut microbes, and host and microbial metabolites. This study lays the framework for mechanistic studies aimed at targeting the microbiome to prevent or treat metabolic endotoxemia in HIV-infected individuals.
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Affiliation(s)
- Abigail J S Armstrong
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
- Department of Immunology and Microbiology, University of Colorado Denver, Aurora, Colorado, USA
- Center for Advanced Biotechnology and Medicine, Rutgers the State University, Piscataway, New Jersey, USA
| | - Kevin Quinn
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado, USA
| | - Jennifer Fouquier
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | - Sam X Li
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | | | - Nichole M Nusbacher
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | - Katrina A Doenges
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado, USA
| | - Suzanne Fiorillo
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | - Tyson J Marden
- Colorado Clinical and Translational Sciences Institute, Aurora, Colorado, USA
| | - Janine Higgins
- Department of Pediatrics, Section of Endocrinology, University of Colorado, Aurora, Colorado, USA
| | - Nichole Reisdorph
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado, USA
| | - Thomas B Campbell
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | - Brent E Palmer
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
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23
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Lin A, Liu J, Gong P, Chen Y, Zhang H, Zhang Y, Yu Y. Serum amyloid A inhibits astrocyte migration via activating p38 MAPK. J Neuroinflammation 2020; 17:254. [PMID: 32861245 PMCID: PMC7456509 DOI: 10.1186/s12974-020-01924-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 08/13/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The accumulation of astrocytes around senile plaques is one of the pathological characteristics in Alzheimer's disease (AD). Serum amyloid A (SAA), known as a major acute-phase protein, colocalizes with senile plaques in AD patients. Here, we demonstrate the role of SAA in astrocyte migration. METHODS The effects of SAA on astrocyte activation and accumulation around amyloid β (Aβ) deposits were detected in APP/PS1 transgenic mice mated with Saa3-/- mice. SAA expression, astrocyte activation, and colocalization with Aβ deposits were evaluated in mice using immunofluorescence staining and/or Western blotting. The migration of primary cultures of mouse astrocytes and human glioma U251 cells was examined using Boyden chamber assay and scratch-would assay. The actin and microtubule networks, protrusion formation, and Golgi apparatus location in astrocytes were determined using scratch-would assay and immunofluorescence staining. RESULTS Saa3 expression was significantly induced in aged APP/PS1 transgenic mouse brain. Saa3 deficiency exacerbated astrocyte activation and increased the number of astrocytes around Aβ deposits in APP/PS1 mice. In vitro studies demonstrated that SAA inhibited the migration of primary cultures of astrocytes and U251 cells. Mechanistic studies showed that SAA inhibited astrocyte polarization and protrusion formation via disrupting actin and microtubule reorganization and Golgi reorientation. Inhibition of the p38 MAPK pathway abolished the suppression of SAA on astrocyte migration and polarization. CONCLUSIONS These results suggest that increased SAA in the brain of APP/PS1 mice inhibits the migration of astrocytes to amyloid plaques by activating the p38 MAPK pathway.
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Affiliation(s)
- Aihua Lin
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jin Liu
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.,State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ping Gong
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yanqing Chen
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haibo Zhang
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yan Zhang
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yang Yu
- Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
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24
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Kawasaki H, Murakami T, Badr Y, Kamiya S, Shimizu K, Okada A, Inoshima Y. In vitro and ex vivo expression of serum amyloid A3 in mouse lung epithelia. Exp Lung Res 2020; 46:352-361. [PMID: 32842790 DOI: 10.1080/01902148.2020.1809750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND AND PURPOSE Serum amyloid A (SAA), an acute-phase protein whose level tracks infection and inflammation, is the precursor protein of amyloid A (AA) fibrils that is thought to cause AA amyloidosis in human and animals. SAA protein has several isoforms based on the difference of amino acid sequence, such as SAA1 to SAA4 in mice. AA fibrils are associated with chronic inflammation and are mainly originated from SAA1 produced in the liver. SAA3 reportedly contributes to the innate immune response in epithelia; however, little is known about its role at the lung epithelia. Therefore, we investigated SAA3 expression in the lung epithelium activated by bacterial antigens. MATERIALS AND METHODS The expressions of SAA3 and SAA1 mRNA were investigated using quantitative real-time PCR, in vitro using mouse Clara (Club) cells and ex vivo using surgically removed mouse lungs, after their stimulation by using either lipopolysaccharide (LPS), the major outer membranous antigen of gram-negative bacteria, or lipoteichoic acid (LTA), the major outer membranous antigen of gram-positive bacteria. In addition, SAA3 and SAA1/2 proteins in treated lung samples were detected by immunohistochemistry (IHC). RESULTS SAA3 mRNA expression increased in cells and lungs treated with either LPS or LTA. SAA3 mRNA was more sensitively expressed in LPS than LTA treatment. In contrast, SAA1 mRNA expression did not increase by either LPS or LTA treatment. Furthermore, SAA3 mRNA expression increased in a dose-dependent manner in cells treated with tumor necrosis factor-alpha. By IHC, SAA3 protein was highly expressed in the luminal side of the bronchial epithelium, while SAA1/2 was not expressed. CONCLUSION These results obtained from in vitro and ex vivo experiments suggest that SAA3 plays an important role in the innate immune response to bacterial infection in the lung epithelia.
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Affiliation(s)
- Haruka Kawasaki
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan
| | - Tomoaki Murakami
- Laboratory of Veterinary Toxicology, Cooperative Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Yassien Badr
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan.,Faculty of Veterinary Medicine, Department of Animal Medicine (Infectious Diseases), Damanhour University, El-Beheira, Egypt
| | - Sato Kamiya
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan
| | - Kaori Shimizu
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan
| | - Ayaka Okada
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu, Japan
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Sciences, Cooperative Department of Veterinary Medicine, Gifu University, Gifu, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu, Japan.,Joint Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
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25
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Biological Characterization of Commercial Recombinantly Expressed Immunomodulating Proteins Contaminated with Bacterial Products in the Year 2020: The SAA3 Case. Mediators Inflamm 2020; 2020:6087109. [PMID: 32694927 PMCID: PMC7362292 DOI: 10.1155/2020/6087109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/19/2020] [Accepted: 06/03/2020] [Indexed: 01/20/2023] Open
Abstract
The serum amyloid A (SAA) gene family is highly conserved and encodes acute phase proteins that are upregulated in response to inflammatory triggers. Over the years, a considerable amount of literature has been published attributing a wide range of biological effects to SAAs such as leukocyte recruitment, cytokine and chemokine expression and induction of matrix metalloproteinases. Furthermore, SAAs have also been linked to protumorigenic, proatherogenic and anti-inflammatory effects. Here, we investigated the biological effects conveyed by murine SAA3 (mu rSAA3) recombinantly expressed in Escherichia coli. We observed the upregulation of a number of chemokines including CCL2, CCL3, CXCL1, CXCL2, CXCL6 or CXCL8 following stimulation of monocytic, fibroblastoid and peritoneal cells with mu rSAA3. Furthermore, this SAA variant displayed potent in vivo recruitment of neutrophils through the activation of TLR4. However, a major problem associated with proteins derived from recombinant expression in bacteria is potential contamination with various bacterial products, such as lipopolysaccharide, lipoproteins and formylated peptides. This is of particular relevance in the case of SAA as there currently exists a discrepancy in biological activity between SAA derived from recombinant expression and that of an endogenous source, i.e. inflammatory plasma. Therefore, we subjected commercial recombinant mu rSAA3 to purification to homogeneity via reversed-phase high-performance liquid chromatography (RP-HPLC) and re-assessed its biological potential. RP-HPLC-purified mu rSAA3 did not induce chemokines and lacked in vivo neutrophil chemotactic activity, but retained the capacity to synergize with CXCL8 in the activation of neutrophils. In conclusion, experimental results obtained when using proteins recombinantly expressed in bacteria should always be interpreted with care.
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26
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Chait A, den Hartigh LJ, Wang S, Goodspeed L, Babenko I, Altemeier WA, Vaisar T. Presence of serum amyloid A3 in mouse plasma is dependent on the nature and extent of the inflammatory stimulus. Sci Rep 2020; 10:10397. [PMID: 32587356 PMCID: PMC7316782 DOI: 10.1038/s41598-020-66898-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/26/2020] [Indexed: 11/09/2022] Open
Abstract
Serum amyloid A3 (Saa3) derives mainly from extrahepatic tissue and is not detected in plasma from moderately inflamed obese mice. In contrast, it is present in plasma from mice acutely inflamed by injection of high dose of lipopolysaccharide (LPS). To reconcile these differences, we evaluated whether different acute inflammatory stimuli could affect the presence of Saa3 in plasma. Saa3 appeared dose dependently in plasma after LPS injection. In contrast, only very low levels were detected after sterile inflammation with silver nitrate despite levels of Saa1 and Saa2 being comparable to high dose LPS. Saa3 was not detected in plasma following casein administration. Although most Saa3 was found in HDL, a small amount was not lipoprotein associated. Gene expression and proteomic analysis of liver and adipose tissue suggested that a major source of Saa3 in plasma after injection of LPS was adipose tissue rather than liver. We conclude that Saa3 only appears in plasma after induction of acute inflammation by some but not all inflammatory stimuli. These findings are consistent with the observation that Saa3 is not detectable in plasma in more moderate chronic inflammatory states such as obesity.
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Affiliation(s)
- Alan Chait
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA.
| | - Laura J den Hartigh
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA
| | - Shari Wang
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA
| | - Leela Goodspeed
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA
| | - Ilona Babenko
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA
| | - William A Altemeier
- Pulmonary, Critical Care and Sleep Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Tomas Vaisar
- Divisions of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98109, USA
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27
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Murata E, Kozaki S, Murakami T, Shimizu K, Okada A, Ishiguro N, Inoshima Y. Differential expression of serum amyloid A1 and A3 in bovine epithelia. J Vet Med Sci 2020; 82:764-770. [PMID: 32378645 PMCID: PMC7324830 DOI: 10.1292/jvms.19-0473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Serum amyloid A (SAA) is both an amyloidogenic protein of amyloid A amyloidosis and an acute phase protein in most animal species. Although SAA isoforms, such as SAA1, 2, 3, and 4, have been identified in cattle, their biological functions are not completely understood. Previous studies using mice indicated that SAA3 mRNA expression increased by stimulation with Escherichia coli and lipopolysaccharide (LPS) in colonic epithelial cells, and subsequently the SAA3 protein enhanced the expression of mucin2 (MUC2) mRNA, which is the major component of the colonic mucus layer. These results suggest that SAA3 plays a role in host innate immunity against bacterial infection in the intestine. In this study, a novel anti-bovine SAA3 monoclonal antibody was produced and SAA3 expression levels in bovine epithelia were examined in vitro and in vivo using real-time PCR and immunohistochemistry (IHC). SAA3 mRNA expression, but not that of SAA1, was enhanced by LPS stimulus in bovine small intestinal and mammary glandular epithelial cells in vitro. Moreover, in bovine epithelia (small intestine, mammary gland, lung, and uterus) obtained from four Holstein dairy cows from a slaughterhouse, SAA3 mRNA expression was higher than that of SAA1. Furthermore, using IHC, SAA3 protein expression was observed in bovine epithelia, whereas SAA1 protein was not. These results suggest that in cattle, SAA3 plays an immunological role against bacterial infection in epithelial tissues, including the small intestine, mammary gland, lung, and uterus.
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Affiliation(s)
- Eriko Murata
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan
| | - Satoi Kozaki
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan
| | - Tomoaki Murakami
- Laboratory of Veterinary Toxicology, Cooperative Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | - Kaori Shimizu
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan
| | - Ayaka Okada
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan
| | - Naotaka Ishiguro
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.,Joint Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
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28
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Pichiah PBT, Sankarganesh D, Arunachalam S, Achiraman S. Adipose-Derived Molecules-Untouched Horizons in Alzheimer's Disease Biology. Front Aging Neurosci 2020; 12:17. [PMID: 32116650 PMCID: PMC7032035 DOI: 10.3389/fnagi.2020.00017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 01/20/2020] [Indexed: 12/18/2022] Open
Abstract
The global incidence of Alzheimer's disease (AD) is on the rise with the increase in obesity and metabolic disease epidemic. Obesity is co-morbid with the increase in mass of adipose tissue, which secretes numerous molecules that are biologically important. Obesity and its associated conditions are perhaps involved in the causative pathway of AD. Immunologically important cytokines such as IL-1β, IL-10, and IL-18, which are released by adipose tissue, are also found to be associated with AD. Besides, the expression of IL-6, IFNγ, and TNF alpha are also associated with AD. Ang-I and Ang-II are found to mediate the progression of AD. Complement factors B, C4b, and H are differentially expressed in AD. Overall, several adipocyte-derived cytokines are found to be dysregulated in AD, and their role in AD remains to be studied. The induction of autophagy is a very promising strategy in the treatment of AD. A variety of adipose-derived molecules have been shown to modulate autophagy. However, very little literature is available on the role of adipose-derived molecules in inducing autophagy in microglial cells of AD. Understanding the role of adipose-derived molecules in the development of AD, especially in the induction of autophagy, would open up new avenues in devising strategies for the treatment of AD.
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Affiliation(s)
| | - Devaraj Sankarganesh
- Department of Biotechnology, School of Bio and Chemical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil, India
- Department of Microbial Biotechnology, Bharathiar University, Coimbatore, India
| | - Sankarganesh Arunachalam
- Department of Biotechnology, School of Bio and Chemical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil, India
| | - Shanmugam Achiraman
- Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, India
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29
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Gut Microbiota and Obesity: A Role for Probiotics. Nutrients 2019; 11:nu11112690. [PMID: 31703257 PMCID: PMC6893459 DOI: 10.3390/nu11112690] [Citation(s) in RCA: 318] [Impact Index Per Article: 63.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/23/2019] [Accepted: 09/24/2019] [Indexed: 02/07/2023] Open
Abstract
Nowadays, obesity is one of the most prevalent human health problems. Research from the last 30 years has clarified the role of the imbalance between energy intake and expenditure, unhealthy lifestyle, and genetic variability in the development of obesity. More recently, the composition and metabolic functions of gut microbiota have been proposed as being able to affect obesity development. Here, we will report the current knowledge on the definition, composition, and functions of intestinal microbiota. We have performed an extensive review of the literature, searching for the following keywords: metabolism, gut microbiota, dysbiosis, obesity. There is evidence for the association between gut bacteria and obesity both in infancy and in adults. There are several genetic, metabolic, and inflammatory pathophysiological mechanisms involved in the interplay between gut microbes and obesity. Microbial changes in the human gut can be considered a factor involved in obesity development in humans. The modulation of the bacterial strains in the digestive tract can help to reshape the metabolic profile in the human obese host as suggested by several data from animal and human studies. Thus, a deep revision of the evidence pertaining to the use probiotics, prebiotics, and antibiotics in obese patients is conceivable
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Abstract
Vitamin A is an essential nutrient for immune system development and function. After absorption from the diet, vitamin A is converted to retinol, which is delivered to cells and tissues by retinol-binding proteins. Serum amyloid A (SAA) proteins are retinol-binding proteins that transport retinol specifically during an infection. In this study, we illuminate the molecular details of how SAA proteins bind to retinol. We present the cocrystal structure of mouse SAA3 bound to retinol, which reveals that 3 molecules of SAA3 assemble to form a deep binding pocket that protects retinol, a fat-soluble molecule, from the aqueous environment. Our findings thus provide structural insight into how retinol is transported throughout the body during infection. Serum amyloid A (SAA) proteins are strongly induced in the liver by systemic infection and in the intestine by bacterial colonization. In infected mice, SAA proteins circulate in association with the vitamin A derivative retinol, suggesting that SAAs transport retinol during infection. Here we illuminate a structural basis for the retinol–SAA interaction. In the bloodstream of infected mice, most SAA is complexed with high-density lipoprotein (HDL). However, we found that the majority of the circulating retinol was associated with the small fraction of SAA proteins that circulate without binding to HDL, thus identifying free SAA as the predominant retinol-binding form in vivo. We then determined the crystal structure of retinol-bound mouse SAA3 at a resolution of 2.2 Å. Retinol-bound SAA3 formed a novel asymmetric trimeric assembly that was generated by the hydrophobic packing of the conserved amphipathic helices α1 and α3. This hydrophobic packing created a retinol-binding pocket in the center of the trimer, which was confirmed by mutagenesis studies. Together, these findings illuminate the molecular basis for retinol transport by SAA proteins during infection.
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31
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Iwata A, Shimizu K, Kawasaki H, Okada A, Inoshima Y. Lipopolysaccharide and lipoteichoic acid enhance serum amyloid A3 mRNA expression in murine alveolar epithelial cells. J Vet Med Sci 2019; 81:1409-1412. [PMID: 31391358 PMCID: PMC6863727 DOI: 10.1292/jvms.19-0154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Serum amyloid A (SAA) is an acute-phase protein indicative of inflammation. In murine
colonic epithelial cells, lipopolysaccharide (LPS), a gram-negative bacterial antigen,
strongly enhanced mRNA expression of SAA3, but not SAA1 or SAA2, suggesting that SAA3
might respond to bacterial infection in other epithelia. We examined SAA1/2 and SAA3 mRNA
expression in murine alveolar epithelial cells exposed to LPS or the gram-positive
bacterial antigen, lipoteichoic acid (LTA), using real-time PCR. LPS enhanced SAA3 mRNA
expression at lower concentrations than did LTA, whereas SAA1/2 mRNA expression was not
enhanced by either LPS or LTA. These results suggest that SAA3 expression is enhanced in
lung epithelium upon bacterial infection as part of innate immunity, with higher
sensitivity to LPS than to LTA.
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Affiliation(s)
- Ami Iwata
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, Gifu 501-1193, Japan
| | - Kaori Shimizu
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, Gifu 501-1193, Japan
| | - Haruka Kawasaki
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, Gifu 501-1193, Japan
| | - Ayaka Okada
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, Gifu 501-1193, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, Gifu 501-1193, Japan.,Education and Research Center for Food Animal Health, Gifu University (GeFAH), Gifu 501-1193, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.,Joint Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
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32
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Inoshima Y, Iwata A, Okada A. Up-regulation of serum amyloid A3 mRNA expression after stimulation with lipopolysaccharide and lipoteichoic acid in mouse lung cells. Amyloid 2019; 26:117-118. [PMID: 31343319 DOI: 10.1080/13506129.2019.1585341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Yasuo Inoshima
- a Cooperative Department of Veterinary Medicine, Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan.,b Education and Research Center for Food Animal Health (GeFAH), Gifu University , Gifu , Japan.,c The United Graduate School of Veterinary Sciences, Gifu University , Gifu , Japan
| | - Ami Iwata
- a Cooperative Department of Veterinary Medicine, Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan
| | - Ayaka Okada
- a Cooperative Department of Veterinary Medicine, Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan.,b Education and Research Center for Food Animal Health (GeFAH), Gifu University , Gifu , Japan
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33
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Abstract
Serum amyloid A (SAA) proteins were isolated and named over 50 years ago. They are small (104 amino acids) and have a striking relationship to the acute phase response with serum levels rising as much as 1000-fold in 24 hours. SAA proteins are encoded in a family of closely-related genes and have been remarkably conserved throughout vertebrate evolution. Amino-terminal fragments of SAA can form highly organized, insoluble fibrils that accumulate in “secondary” amyloid disease. Despite their evolutionary preservation and dynamic synthesis pattern SAA proteins have lacked well-defined physiologic roles. However, considering an array of many, often unrelated, reports now permits a more coordinated perspective. Protein studies have elucidated basic SAA structure and fibril formation. Appreciating SAA’s lipophilicity helps relate it to lipid transport and metabolism as well as atherosclerosis. SAA’s function as a cytokine-like protein has become recognized in cell-cell communication as well as feedback in inflammatory, immunologic, neoplastic and protective pathways. SAA likely has a critical role in control and possibly propagation of the primordial acute phase response. Appreciating the many cellular and molecular interactions for SAA suggests possibilities for improved understanding of pathophysiology as well as treatment and disease prevention.
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Affiliation(s)
- George H Sack
- Departments of Biological Chemistry and Medicine, The Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Physiology 615, Baltimore, MD, 21205, USA.
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34
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Wang L, Yu K, Zhang X, Yu S. Dual functional roles of the MyD88 signaling in colorectal cancer development. Biomed Pharmacother 2018; 107:177-184. [PMID: 30086464 DOI: 10.1016/j.biopha.2018.07.139] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/24/2018] [Accepted: 07/25/2018] [Indexed: 12/12/2022] Open
Abstract
The myeloid differentiation factor 88 (MyD88), an adaptor protein in regulation of the innate immunity, functions to regulate immune responses against viral and bacterial infections in the human body. Toll-like receptors (TLRs) and interleukin 1 receptors (IL-1R) can recognize microbes or endogenous ligands and then recruit MyD88 to activate the MyD88-dependent pathway, while MyD88 mutation associated with lymphoma development and altered MyD88 signaling also involved in cancer-associated cell intrinsic and extrinsic inflammation progression and carcinogenesis. Detection of MyD88 expression was to predict prognosis of various human cancers, e.g., lymphoid, liver, and colorectal cancers. In human cancers, MyD88 protein acts as a bridge between the inflammatory signaling from the TLR/IL-1R and Ras oncogenic signaling pathway. However, the MyD88 signaling played dual functional roles in colorectal cancer, i.e., the tumor-promoting role that enhances cancer inflammation and intestinal flora imbalance to induce tumor invasion and tumor cell self-renewal, and the anti-tumor role that helps to maintain the host-microbiota homeostasis to induce tumor cell cycle arrest and immune responses against cancer cells. This review precisely discusses the up to date literature for these contrasting effects of MyD88 signaling on colorectal cancer development and progression.
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Affiliation(s)
- Lu Wang
- Department of Pharmacy, Jinan Central Hospital Affiliated to Shandong University, Jinan, China
| | - Kewei Yu
- Department of Pharmacy, Jinan Central Hospital Affiliated to Shandong University, Jinan, China
| | - Xiang Zhang
- Department of Pharmacy, Jinan Central Hospital Affiliated to Shandong University, Jinan, China
| | - Shuwen Yu
- Department of Pharmacy, Jinan Central Hospital Affiliated to Shandong University, Jinan, China.
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35
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Hartley GP, Chow L, Ammons DT, Wheat WH, Dow SW. Programmed Cell Death Ligand 1 (PD-L1) Signaling Regulates Macrophage Proliferation and Activation. Cancer Immunol Res 2018; 6:1260-1273. [PMID: 30012633 DOI: 10.1158/2326-6066.cir-17-0537] [Citation(s) in RCA: 218] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 01/18/2018] [Accepted: 07/10/2018] [Indexed: 11/16/2022]
Abstract
Tumor-associated macrophages (TAMs) express programmed cell death ligand 1 (PD-L1) and contribute to the immune-suppressive tumor microenvironment. Although the role of the PD-L1 and PD-1 interaction to regulate T-cell suppression is established, less is known about PD-L1 signaling in macrophages and how these signals may affect the function of TAMs. We used in vitro and in vivo models to investigate PD-L1 signaling in macrophages and the effects of PD-L1 antibody treatment on TAM responses. Treatment of mouse and human macrophages with PD-L1 antibodies increased spontaneous macrophage proliferation, survival, and activation (costimulatory molecule expression, cytokine production). Similar changes were observed in macrophages incubated with soluble CD80 and soluble PD-1, and in PD-L1-/- macrophages. Macrophage treatment with PD-L1 antibodies upregulated mTOR pathway activity, and RNAseq analysis revealed upregulation of multiple macrophage inflammatory pathways. In vivo, treatment with PD-L1 antibody resulted in increased tumor infiltration with activated macrophages. In tumor-bearing RAG-/- mice, upregulated costimulatory molecule expression by TAMs and reduced tumor growth were observed. Combined PD-1/ PD-L1 antibody treatment of animals with established B16 melanomas cured half of the treated mice, whereas treatment with single antibodies had little therapeutic effect. These findings indicate that PD-L1 delivers a constitutive negative signal to macrophages, resulting in an immune-suppressive cell phenotype. Treatment with PD-L1 antibodies reverses this phenotype and triggers macrophage-mediated antitumor activity, suggesting a distinct effect of PD-L1, but not PD-1, antibody treatment. Cancer Immunol Res; 6(10); 1260-73. ©2018 AACR.
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Affiliation(s)
- Genevieve P Hartley
- Animal Cancer Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, Colorado
| | - Lyndah Chow
- Animal Cancer Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, Colorado
| | - Dylan T Ammons
- Animal Cancer Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, Colorado
| | - William H Wheat
- Animal Cancer Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, Colorado
| | - Steven W Dow
- Animal Cancer Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, Colorado.
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36
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Choudhary S, Santone E, Yee SP, Lorenzo J, Adams DJ, Goetjen A, McCarthy MB, Mazzocca AD, Pilbeam C. Continuous PTH in Male Mice Causes Bone Loss Because It Induces Serum Amyloid A. Endocrinology 2018; 159:2759-2776. [PMID: 29757436 PMCID: PMC6692876 DOI: 10.1210/en.2018-00265] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 05/05/2018] [Indexed: 12/12/2022]
Abstract
Increased bone resorption is considered to explain why intermittent PTH is anabolic for bone but continuous PTH is catabolic. However, when cyclooxygenase-2 (COX2) is absent in mice, continuous PTH becomes anabolic without decreased resorption. In murine bone marrow stromal cells (BMSCs), serum amyloid A (SAA)3, induced in the hematopoietic lineage by the combination of COX2-produced prostaglandin and receptor activator of nuclear factor κB ligand (RANKL), suppresses PTH-stimulated osteoblast differentiation. To determine whether SAA3 inhibits the anabolic effects of PTH in vivo, wild-type (WT) and SAA3 knockout (KO) mice were infused with PTH. In WT mice, continuous PTH induced SAA3 and was catabolic for bone. In KO mice, PTH was anabolic, increasing trabecular bone, serum markers of bone formation, and osteogenic gene expression. In contrast, PTH increased all measurements associated with bone resorption, as well as COX2 gene expression, similarly in KO and WT mice. SAA1 and SAA2 in humans are likely to have analogous functions to SAA3 in mice. RANKL induced both SAA1 and SAA2 in human bone marrow macrophages in a COX2-dependent manner. PTH stimulated osteogenesis in human BMSCs only when COX2 or RANKL was inhibited. Addition of recombinant SAA1 or SAA2 blocked PTH-stimulated osteogenesis. In summary, SAA3 suppresses the bone formation responses but not the bone resorption responses to PTH in mice, and in the absence of SAA3, continuous PTH is anabolic. In vitro studies in human bone marrow suggest that SAA may be a target for enhancing the therapeutic effects of PTH in treating osteoporosis.
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Affiliation(s)
- Shilpa Choudhary
- Musculoskeletal Institute, UConn Health, Farmington, Connecticut
- Department of Medicine, UConn Health, Farmington, Connecticut
| | | | - Sui-Pok Yee
- Department of Cell Biology, UConn Health, Farmington, Connecticut
- Center for Mouse Genome Modification, UConn Health, Farmington, Connecticut
| | - Joseph Lorenzo
- Musculoskeletal Institute, UConn Health, Farmington, Connecticut
- Department of Medicine, UConn Health, Farmington, Connecticut
| | - Douglas J Adams
- Musculoskeletal Institute, UConn Health, Farmington, Connecticut
| | | | | | | | - Carol Pilbeam
- Musculoskeletal Institute, UConn Health, Farmington, Connecticut
- Department of Medicine, UConn Health, Farmington, Connecticut
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37
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The crosstalk of gut microbiota and chronic kidney disease: role of inflammation, proteinuria, hypertension, and diabetes mellitus. Int Urol Nephrol 2018; 50:1453-1466. [PMID: 29728993 DOI: 10.1007/s11255-018-1873-2] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 04/13/2018] [Indexed: 12/11/2022]
Abstract
Chronic kidney disease (CKD) has been shown to result in profound changes in the composition and functions of the gut microbial flora which by disrupting intestinal epithelial barrier and generating toxic by-products contributes to systemic inflammation and the associated complications. On the other hand, emerging evidence points to the role of the gut microbiota in the development and progression of CKD by provoking inflammation, proteinuria, hypertension, and diabetes. These observations demonstrate the causal interconnection between the gut microbial dysbiosis and CKD. The gut microbiota closely interacts with the inflammatory, renal, cardiovascular, and endocrine systems via metabolic, humoral, and neural signaling pathways, events which can lead to chronic systemic inflammation, proteinuria, hypertension, diabetes, and kidney disease. Given the established role of the gut microbiota in the development and progression of CKD and its complications, favorable modification of the composition and function of the gut microbiome represents an appealing therapeutic target for prevention and treatment of CKD. This review provides an overview of the role of the gut microbial dysbiosis in the pathogenesis of the common causes of CKD including hypertension, diabetes, and proteinuria as well as progression of CKD.
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38
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Ather JL, Poynter ME. Serum amyloid A3 is required for normal weight and immunometabolic function in mice. PLoS One 2018; 13:e0192352. [PMID: 29390039 PMCID: PMC5794179 DOI: 10.1371/journal.pone.0192352] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 01/22/2018] [Indexed: 02/06/2023] Open
Abstract
Serum amyloid A (SAA) is an apolipoprotein that is robustly upregulated in numerous inflammatory diseases and has been implicated as a candidate pro-inflammatory mediator. However, studies comparing endogenous SAAs and recombinant forms of the acute phase protein have generated conflicting data on the function of SAA in immunity. We generated SAA3 knockout mice to evaluate the contribution of SAA3 to immune-mediated disease, and found that mice lacking SAA3 develop adult-onset obesity and metabolic dysfunction along with defects in innate immune development. Mice that lack SAA3 gain more weight, exhibit increased visceral adipose deposition, and develop hepatic steatosis compared to wild-type littermates. Leukocytes from the adipose tissue of SAA3-/- mice express a pro-inflammatory phenotype, and bone marrow derived dendritic cells from mice lacking SAA3 secrete increased levels of IL-1β, IL-6, IL-23, and TNFα in response to LPS compared to cells from wild-type mice. Finally, BMDC lacking SAA3 demonstrate an impaired endotoxin tolerance response and inhibited responses to retinoic acid. Our findings indicate that endogenous SAA3 modulates metabolic and immune homeostasis.
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Affiliation(s)
- Jennifer L. Ather
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT, United States of America
| | - Matthew E. Poynter
- Vermont Lung Center, Division of Pulmonary Disease and Critical Care, Department of Medicine, University of Vermont, Burlington, VT, United States of America
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39
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Serum Amyloid A1 Is an Epithelial Prorestitutive Factor. THE AMERICAN JOURNAL OF PATHOLOGY 2018; 188:937-949. [PMID: 29366677 DOI: 10.1016/j.ajpath.2017.12.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 11/10/2017] [Accepted: 12/05/2017] [Indexed: 12/12/2022]
Abstract
Several proteins endogenously produced during the process of intestinal wound healing have demonstrated prorestitutive properties. The presence of serum amyloid A1 (SAA1), an acute-phase reactant, within inflamed tissues, where it exerts chemotaxis of phagocytes, is well recognized; however, a putative role in intestinal wound repair has not been described. Herein, we show that SAA1 induces intestinal epithelial cell migration, spreading, and attachment through a formyl peptide receptor 2-dependent mechanism. Induction of the prorestitutive phenotype is concentration and time dependent and is associated with epithelial reactive oxygen species production and alterations in p130 Crk-associated substrate staining. In addition, using a murine model of wound recovery, we provide evidence that SAA1 is dynamically and temporally regulated, and that the elaboration of SAA1 within the wound microenvironment correlates with the influx of SAA1/CD11b coexpressing immune cells and increases in cytokines known to induce SAA expression. Overall, the present work demonstrates an important role for SAA in epithelial wound recovery and provides evidence for a physiological role in the wound environment.
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40
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Saa3 is a key mediator of the protumorigenic properties of cancer-associated fibroblasts in pancreatic tumors. Proc Natl Acad Sci U S A 2018; 115:E1147-E1156. [PMID: 29351990 DOI: 10.1073/pnas.1717802115] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is characterized by the presence of abundant desmoplastic stroma primarily composed of cancer-associated fibroblasts (CAFs). It is generally accepted that CAFs stimulate tumor progression and might be implicated in drug resistance and immunosuppression. Here, we have compared the transcriptional profile of PDGFRα+ CAFs isolated from genetically engineered mouse PDAC tumors with that of normal pancreatic fibroblasts to identify genes potentially implicated in their protumorigenic properties. We report that the most differentially expressed gene, Saa3, a member of the serum amyloid A (SAA) apolipoprotein family, is a key mediator of the protumorigenic activity of PDGFRα+ CAFs. Whereas Saa3-competent CAFs stimulate the growth of tumor cells in an orthotopic model, Saa3-null CAFs inhibit tumor growth. Saa3 also plays a role in the cross talk between CAFs and tumor cells. Ablation of Saa3 in pancreatic tumor cells makes them insensitive to the inhibitory effect of Saa3-null CAFs. As a consequence, germline ablation of Saa3 does not prevent PDAC development in mice. The protumorigenic activity of Saa3 in CAFs is mediated by Mpp6, a member of the palmitoylated membrane protein subfamily of the peripheral membrane-associated guanylate kinases (MAGUK). Finally, we interrogated whether these observations could be translated to a human scenario. Indeed, SAA1, the ortholog of murine Saa3, is overexpressed in human CAFs. Moreover, high levels of SAA1 in the stromal component correlate with worse survival. These findings support the concept that selective inhibition of SAA1 in CAFs may provide potential therapeutic benefit to PDAC patients.
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41
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Tannock LR, De Beer MC, Ji A, Shridas P, Noffsinger VP, den Hartigh L, Chait A, De Beer FC, Webb NR. Serum amyloid A3 is a high density lipoprotein-associated acute-phase protein. J Lipid Res 2017; 59:339-347. [PMID: 29247043 DOI: 10.1194/jlr.m080887] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/22/2017] [Indexed: 12/20/2022] Open
Abstract
Serum amyloid A (SAA) is a family of acute-phase reactants. Plasma levels of human SAA1/SAA2 (mouse SAA1.1/2.1) can increase ≥1,000-fold during an acute-phase response. Mice, but not humans, express a third relatively understudied SAA isoform, SAA3. We investigated whether mouse SAA3 is an HDL-associated acute-phase SAA. Quantitative RT-PCR with isoform-specific primers indicated that SAA3 and SAA1.1/2.1 are induced similarly in livers (∼2,500-fold vs. ∼6,000-fold, respectively) and fat (∼400-fold vs. ∼100-fold, respectively) of lipopolysaccharide (LPS)-injected mice. In situ hybridization demonstrated that all three SAAs are produced by hepatocytes. All three SAA isoforms were detected in plasma of LPS-injected mice, although SAA3 levels were ∼20% of SAA1.1/2.1 levels. Fast protein LC analyses indicated that virtually all of SAA1.1/2.1 eluted with HDL, whereas ∼15% of SAA3 was lipid poor/free. After density gradient ultracentrifugation, isoelectric focusing demonstrated that ∼100% of plasma SAA1.1 was recovered in HDL compared with only ∼50% of SAA2.1 and ∼10% of SAA3. Thus, SAA3 appears to be more loosely associated with HDL, resulting in lipid-poor/free SAA3. We conclude that SAA3 is a major hepatic acute-phase SAA in mice that may produce systemic effects during inflammation.
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Affiliation(s)
- Lisa R Tannock
- Departments of Internal Medicine, University of Kentucky, Lexington, KY.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY.,Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY.,Veterans Affairs Lexington, University of Kentucky, Lexington, KY
| | - Maria C De Beer
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY.,Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY.,Departments of Physiology, University of Kentucky, Lexington, KY
| | - Ailing Ji
- Departments of Internal Medicine, University of Kentucky, Lexington, KY.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
| | - Preetha Shridas
- Departments of Internal Medicine, University of Kentucky, Lexington, KY.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY.,Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY
| | - Victoria P Noffsinger
- Departments of Internal Medicine, University of Kentucky, Lexington, KY.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY
| | - Laura den Hartigh
- Department of Medicine University of Washington, Seattle, WA.,University of Washington Diabetes Institute, University of Washington, Seattle, WA
| | - Alan Chait
- Department of Medicine University of Washington, Seattle, WA.,University of Washington Diabetes Institute, University of Washington, Seattle, WA
| | - Frederick C De Beer
- Departments of Internal Medicine, University of Kentucky, Lexington, KY.,Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY.,Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY
| | - Nancy R Webb
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY .,Barnstable Brown Diabetes Center, University of Kentucky, Lexington, KY.,Veterans Affairs Lexington, University of Kentucky, Lexington, KY.,Departments of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY
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42
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Arroyo J, Hosseini A, Zhou Z, Alharthi A, Trevisi E, Osorio J, Loor J. Reticulo-rumen mass, epithelium gene expression, and systemic biomarkers of metabolism and inflammation in Holstein dairy cows fed a high-energy diet. J Dairy Sci 2017; 100:9352-9360. [DOI: 10.3168/jds.2017-12866] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 08/03/2017] [Indexed: 01/04/2023]
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43
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Feng Z, Long W, Hao B, Ding D, Ma X, Zhao L, Pang X. A human stool-derived Bilophila wadsworthia strain caused systemic inflammation in specific-pathogen-free mice. Gut Pathog 2017; 9:59. [PMID: 29090023 PMCID: PMC5657053 DOI: 10.1186/s13099-017-0208-7] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/17/2017] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Bilophila wadsworthia is a major member of sulfidogenic bacteria in human gut, it was originally recovered from different clinical specimens of intra-abdominal infections and recently was reported potentially linked to different chronic metabolic disorders. However, there is still insufficient understanding on its detailed function and mechanism to date. METHODS A B. wadsworthia strain was isolated from fresh feces of a latent autoimmune diabetes in adults patient and we investigated its pathogenicity by oral administration to specific-pathogen-free mice. Tissue samples and serum were collected after sacrifice. Stool samples were collected at different time points to profile the gut microbiota. RESULTS Bilophila wadsworthia infection resulted in the reduction of body weight and fat mass, apparent hepatosplenomegaly and elevated serum inflammatory factors, including serum amyloid A and interleukin-6, while without significant change of the overall gut microbiota structure. CONCLUSIONS These results demonstrated that higher amount of B. wadsworthia caused systemic inflammatory response in SPF mice, which adds new evidence to the pathogenicity of this bacterium and implied its potential role to the chronic inflammation related metabolic diseases like diabetes.
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Affiliation(s)
- Zhou Feng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Wenmin Long
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Binhan Hao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Ding Ding
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Xiaoqing Ma
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Liping Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
| | - Xiaoyan Pang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240 China
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44
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He M, Shi B. Gut microbiota as a potential target of metabolic syndrome: the role of probiotics and prebiotics. Cell Biosci 2017; 7:54. [PMID: 29090088 PMCID: PMC5655955 DOI: 10.1186/s13578-017-0183-1] [Citation(s) in RCA: 173] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/04/2017] [Indexed: 12/19/2022] Open
Abstract
Metabolic syndrome (MS) comprises central obesity, increased plasma glucose levels, hyperlipidemia and hypertension, and its incidence is increasing due to changes in lifestyle and dietary structure in recent years. MS has been proven to be associated with an increased incidence of cardiovascular diseases and type 2 diabetes mellitus, leading to morbidity and mortality. In this manuscript, we review recent studies concerning the role of the gut microbiota in MS modulation. Manipulation of the gut microbiota through the administration of prebiotics or probiotics may assist in weight loss and reduce plasma glucose and serum lipid levels, decreasing the incidence of cardiovascular diseases and type 2 diabetes mellitus. To the best of our knowledge, short-chain fatty acids (SCFAs), bile salt hydrolase (BSH), metabolic endotoxemia and the endocannabinoid (eCB) system are essential in regulating the initiation and progression of MS through the normalization of adipogenesis and the regulation of insulin secretion, fat accumulation, energy homeostasis, and plasma cholesterol levels. Therefore, the gut microbiota may serve as a potential therapeutic target for MS. However, further studies are needed to enhance our understanding of manipulating the gut microbiota and the role of the gut microbiota in MS prevention and treatment.
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Affiliation(s)
- Mingqian He
- Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, 277 West Yanta Road, Xi'an, 710061 Shaanxi People's Republic of China
| | - Bingyin Shi
- Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, 277 West Yanta Road, Xi'an, 710061 Shaanxi People's Republic of China
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45
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Tashiro M, Iwata A, Yamauchi M, Shimizu K, Okada A, Ishiguro N, Inoshima Y. The N-terminal region of serum amyloid A3 protein activates NF-κB and up-regulates MUC2 mucin mRNA expression in mouse colonic epithelial cells. PLoS One 2017; 12:e0181796. [PMID: 28738073 PMCID: PMC5524290 DOI: 10.1371/journal.pone.0181796] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/09/2017] [Indexed: 01/01/2023] Open
Abstract
Serum amyloid A (SAA) is the major acute-phase protein and a precursor of amyloid A (AA) in AA amyloidosis in humans and animals. SAA isoforms have been identified in a wide variety of animals, such as SAA1, SAA2, SAA3, and SAA4 in mouse. Although the biological functions of SAA isoforms are not completely understood, recent studies have suggested that SAA3 plays a role in host defense. Expression of SAA3 is increased on the mouse colon surface in the presence of microbiota in vivo, and it increases mRNA expression of mucin 2 (MUC2) in murine colonic epithelial cells in vitro, which constitutes a protective mucus barrier in the intestinal tract. In this study, to identify responsible regions in SAA3 for MUC2 expression, recombinant murine SAA1 (rSAA1), rSAA3, and rSAA1/3, a chimera protein constructed with mature SAA1 (amino acids 1–36) and SAA3 (amino acids 37–103), and vice versa for rSAA3/1, were added to murine colonic epithelial CMT-93 cells, and the mRNA expressions of MUC2 and cytokines were measured. Inhibition assays with NF-κB inhibitor or TLR4/MD2 inhibitor were also performed. Up-regulation of MUC2 mRNA expression was strongly stimulated by rSAA3 and rSAA3/1, but not by rSAA1 or rSAA1/3. Moreover, NF-κB and TLR4/MD2 inhibitors suppressed the increase of MUC2 mRNA expression. These results suggest that the major responsible region for MUC2 expression exists in amino acids 1–36 of SAA3, and that up-regulations of MUC2 expression by SAA3 and SAA3/1 are involved with activation of NF-κB via the TLR4/MD2 complex.
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Affiliation(s)
- Manami Tashiro
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Ami Iwata
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Marika Yamauchi
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Kaori Shimizu
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Ayaka Okada
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Naotaka Ishiguro
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
- Education and Research Center for Food Animal Health, Gifu University (GeFAH), Yanagido, Gifu, Gifu, Japan
- * E-mail:
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46
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Inoshima Y, Tashiro M, Ishiguro N. N-terminal region of serum amyloid A3 is responsible for up-regulation of MUC2 mRNA expression in mouse epithelial cells. Amyloid 2017; 24:18-19. [PMID: 28434344 DOI: 10.1080/13506129.2017.1291419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Yasuo Inoshima
- a Department of Veterinary Medicine , Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan and.,b The United Graduate School of Veterinary Sciences, Gifu University , Gifu , Japan
| | - Manami Tashiro
- a Department of Veterinary Medicine , Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan and
| | - Naotaka Ishiguro
- a Department of Veterinary Medicine , Laboratory of Food and Environmental Hygiene, Gifu University , Gifu , Japan and.,b The United Graduate School of Veterinary Sciences, Gifu University , Gifu , Japan
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47
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Djuric Z. Obesity-associated cancer risk: the role of intestinal microbiota in the etiology of the host proinflammatory state. Transl Res 2017; 179:155-167. [PMID: 27522986 PMCID: PMC5164980 DOI: 10.1016/j.trsl.2016.07.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 07/10/2016] [Accepted: 07/20/2016] [Indexed: 02/06/2023]
Abstract
Obesity increases the risks of many cancers. One important mechanism behind this association is the obesity-associated proinflammatory state. Although the composition of the intestinal microbiome undoubtedly can contribute to the proinflammatory state, perhaps the most important aspect of host-microbiome interactions is host exposure to components of intestinal bacteria that stimulate inflammatory reactions. Systemic exposures to intestinal bacteria can be modulated by dietary factors through altering both the composition of the intestinal microbiota and the absorption of bacterial products from the intestinal lumen. In particular, high-fat and high-energy diets have been shown to facilitate absorption of bacterial lipopolysaccharide (LPS) from intestinal bacteria. Biomarkers of bacterial exposures that have been measured in blood include LPS-binding protein, sCD14, fatty acids characteristic of intestinal bacteria, and immunoglobulins specific for bacterial LPS and flagellin. The optimal strategies to reduce these proinflammatory exposures, whether by altering diet composition, avoiding a positive energy balance, or reducing adipose stores, likely differ in each individual. Biomarkers that assess systemic bacterial exposures therefore should be useful to (1) optimize and personalize preventive approaches for individuals and groups with specific characteristics and to (2) gain insight into the possible mechanisms involved with different preventive approaches.
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Affiliation(s)
- Zora Djuric
- Department of Family Medicine, University of Michigan, Ann Arbor, Mich; Department of Nutritional Sciences, University of Michigan, Ann Arbor, Mich.
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48
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Aguirre M, Venema K. Challenges in simulating the human gut for understanding the role of the microbiota in obesity. Benef Microbes 2016; 8:31-53. [PMID: 27903093 DOI: 10.3920/bm2016.0113] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
There is an elevated incidence of cases of obesity worldwide. Therefore, the development of strategies to tackle this condition is of vital importance. This review focuses on the necessity of optimising in vitro systems to model human colonic fermentation in obese subjects. This may allow to increase the resolution and the physiological relevance of the information obtained from this type of studies when evaluating the potential role that the human gut microbiota plays in obesity. In light of the parameters that are currently used for the in vitro simulation of the human gut (which are mostly based on information derived from healthy subjects) and the possible difference with an obese condition, we propose to revise and improve specific standard operating procedures.
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Affiliation(s)
- M Aguirre
- 1 Top Institute of Food and Nutrition, P.O. Box 557, 6700 AA Wageningen, the Netherlands.,2 Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands.,3 The Netherlands Organization for Applied Scientific Research (TNO), P.O. Box 360, 3700 AJ Zeist, the Netherlands
| | - K Venema
- 1 Top Institute of Food and Nutrition, P.O. Box 557, 6700 AA Wageningen, the Netherlands.,2 Department of Human Biology, Faculty of Health, Medicine and Life Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands.,4 Beneficial Microbes Consultancy, Johan Karschstraat 3, 6709 TN Wageningen, the Netherlands
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Salvesen Ø, Reiten MR, Heegaard PMH, Tranulis MA, Espenes A, Skovgaard K, Ersdal C. Activation of innate immune genes in caprine blood leukocytes after systemic endotoxin challenge. BMC Vet Res 2016; 12:241. [PMID: 27793136 PMCID: PMC5084394 DOI: 10.1186/s12917-016-0870-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/20/2016] [Indexed: 12/19/2022] Open
Abstract
Background Sepsis is a serious health problem associated with a range of infectious diseases in animals and humans. Early events of this syndrome can be mimicked by experimental administration of lipopolysaccharides (LPS). Compared with mice, small ruminants and humans are highly sensitive to LPS, making goats valuable in inflammatory models. We performed a longitudinal study in eight Norwegian dairy goats that received LPS (0.1 μg/kg, Escherichia coli O26:B6) intravenously. A control group of five goats received corresponding volumes of sterile saline. Clinical examinations were performed continuously, and blood samples were collected throughout the trial. Results Characteristic signs of acute sepsis, such as sickness behavior, fever, and leukopenia were observed within 1 h of LPS administration. A high-throughput longitudinal gene expression analysis of circulating leukocytes was performed, and genes associated with the acute phase response, type I interferon signaling, LPS cascade and apoptosis, in addition to cytokines and chemokines were targeted. Pro-inflammatory genes, such as IL1B, CCL3 and IL8, were significantly up-regulated. Interestingly, increased mRNA levels of seven interferon stimulated genes (ISGs) were observed peaking at 2 h, corroborating the increasing evidence that ISGs respond immediately to bacterial endotoxins. A slower response was manifested by four extrahepatic acute phase proteins (APP) (SAA3, HP, LF and LCN2) reaching maximum levels at 5 h. Conclusions We report an immediate induction of ISGs in leukocytes in response to LPS supporting a link between the interferon system and defense against bacterial infections. The extrahepatic expression of APPs suggests that leukocytes contribute to synthesis of these proteins at the beginning of a systemic inflammation. Taken together, these findings provide insights into the dynamic regulation of innate immune genes, as well as raising new questions regarding the importance of ISGs and extrahepatic APPs in leukocytes after systemic endotoxin challenge. Electronic supplementary material The online version of this article (doi:10.1186/s12917-016-0870-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Øyvind Salvesen
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Malin R Reiten
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Peter M H Heegaard
- Innate Immunology Group, Section for Immunology and Vaccinology, National Veterinary Institute, Technical University of Denmark, Frederiksberg, Denmark
| | - Michael A Tranulis
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Arild Espenes
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Kerstin Skovgaard
- Innate Immunology Group, Section for Immunology and Vaccinology, National Veterinary Institute, Technical University of Denmark, Frederiksberg, Denmark
| | - Cecilie Ersdal
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway.
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50
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Expression of the aryl hydrocarbon receptor contributes to the establishment of intestinal microbial community structure in mice. Sci Rep 2016; 6:33969. [PMID: 27659481 PMCID: PMC5034278 DOI: 10.1038/srep33969] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 09/06/2016] [Indexed: 12/14/2022] Open
Abstract
Environmental and genetic factors represent key components in the establishment/maintenance of the intestinal microbiota. The aryl hydrocarbon receptor (AHR) is emerging as a pleiotropic factor, modulating pathways beyond its established role as a xenobiotic sensor. The AHR is known to regulate immune surveillance within the intestine through retention of intraepithelial lymphocytes, functional redistribution of Th17/Treg balance. Consequently, environmental/genetic manipulation of AHR activity likely influences host-microbe homeostasis. Utilizing C57BL6/J Ahr−/+ and Ahr−/− co-housed littermates followed by 18 days of genotypic segregation, we examined the influence of AHR expression upon intestinal microbe composition/functionality and host physiology. 16S sequencing/quantitative PCR (qPCR) revealed significant changes in phyla abundance, particularly Verrucomicrobia together with segmented filamentous bacteria, and an increase in species diversity in Ahr−/− mice following genotypic segregation. Metagenomics/metabolomics indicate microbial composition is associated with functional shifts in bacterial metabolism. Analysis identified Ahr−/−-dependent increases in ileal gene expression, indicating increased inflammatory tone. Transfer of Ahr−/− microbiota to wild-type germ-free mice recapitulated the increase Verrucomicrobia and inflammatory tone, indicating Ahr−/−-microbial dependence. These data suggest a role for the AHR in influencing the community structure of the intestinal microbiota.
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