1
|
Wu W, Zhao Y, Hu T, Long Y, Zeng Y, Li M, Peng S, Hu J, Shen Y. Endoplasmic reticulum stress is upregulated in inflammatory bowel disease and contributed TLR2 pathway-mediated inflammatory response. Immunopharmacol Immunotoxicol 2024; 46:192-198. [PMID: 38147028 DOI: 10.1080/08923973.2023.2298897] [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: 03/22/2023] [Accepted: 12/17/2023] [Indexed: 12/27/2023]
Abstract
OBJECTIVE Endoplasmic reticulum stress (ERS) and Toll-like receptor 2 (TLR2) signaling play an important role in inflammatory bowel disease (IBD); however, the link between TLR2 and ERS in IBD is unclear. This study investigated whether Thapsigargin (TG) -induced ER protein expression levels contributed to TLR2-mediated inflammatory response. METHODS The THP-1 cells were treated with TLR2 agonist (Pam3CSK4), ERS inducer Thapsigargin (TG) or inhibitor (TUDCA). The mRNA expressions of TLR1-TLR10 were detected by qPCR. The production and secretion of inflammatory factors were detected by PCR and ELISA. Immunohistochemistry was used to detect the expressions of GRP78 and TLR2 in the intestinal mucosa of patients with Crohn's disease (CD). The IBD mouse model was established by TNBS in the modeling group. ERS inhibitor (TUDCA) was used in the treatment group. RESULTS The expression of TLRs was detected via polymerase chain reaction (PCR) in THP-1 cells treated by ERS agonist Thapsigargin (TG). According to the findings, TG could promote TLR2 and TLR5 expression. Subsequently, in TLR2 agonist Pam3CSK4 induced THP-1 cells, TG could lead to increased expression of the inflammatory factors such as TNF-α, IL-1β and IL-8, and ERS inhibitor (TUDCA) could block this effect. However, Pam3CSK4 did not significantly impact the GRP78 and CHOP expression. Based upon the immunohistochemical results, TLR2 and GRP78 expression were significantly increased in the intestinal mucosa of patients with Crohn's disease (CD). For in vivo experiments, TUDCA displayed the ability to inhibit intestinal mucosal inflammation and reduce GRP78 and TLR2 proteins. CONCLUSIONS ERS and TLR2 is upregulated in inflammatory bowel disease, ERS may promote TLR2 pathway-mediated inflammatory response. Moreover, ERS and TLR2 signaling could be novel therapeutic targets for IBD.
Collapse
Affiliation(s)
- Weijie Wu
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Yan Zhao
- Department of Pathology, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Tian Hu
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Yan Long
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Ya Zeng
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Mengling Li
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Siyuan Peng
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Jinyue Hu
- Central Laboratory, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| | - Yueming Shen
- Department of Digestive Diseases, Changsha Central Hospital Affiliated to University of South China, Changsha, Hunan, China
| |
Collapse
|
2
|
Ahmad Z, Singh S, Lee TJ, Sharma A, Lydic TA, Giri S, Kumar A. Untargeted and temporal analysis of retinal lipidome in bacterial endophthalmitis. Prostaglandins Other Lipid Mediat 2024; 171:106806. [PMID: 38185280 PMCID: PMC10939753 DOI: 10.1016/j.prostaglandins.2023.106806] [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: 06/09/2023] [Revised: 11/22/2023] [Accepted: 12/26/2023] [Indexed: 01/09/2024]
Abstract
Bacterial endophthalmitis is a blinding infectious disease typically acquired during ocular surgery. We previously reported significant alterations in retinal metabolism during Staphylococcus (S) aureus endophthalmitis. However, the changes in retinal lipid composition during endophthalmitis are unknown. Here, using a mouse model of S. aureus endophthalmitis and an untargeted lipidomic approach, we comprehensively analyzed temporal alterations in total lipids and oxylipin in retina. Our data showed a time-dependent increase in the levels of lipid classes, sphingolipids, glycerolipids, sterols, and non-esterified fatty acids, whereas levels of phospholipids decreased. Among lipid subclasses, phosphatidylcholine decreased over time. The oxylipin analysis revealed increased prostaglandin-E2, hydroxyeicosatetraenoic acids, docosahexaenoic acid, eicosapentaenoic acid, and α-linolenic acid. In-vitro studies using mouse bone marrow-derived macrophages showed increased lipid droplets and lipid-peroxide formation in response to S. aureus infection. Collectively, these findings suggest that S. aureus-infection alters the retinal lipid profile, which may contribute to the pathogenesis of bacterial endophthalmitis.
Collapse
Affiliation(s)
- Zeeshan Ahmad
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Sukhvinder Singh
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Tae Jin Lee
- Augusta University, Augusta, GA, USA. 4 Department of Ophthalmology, Augusta University, Augusta, GA, USA
| | - Ashok Sharma
- Augusta University, Augusta, GA, USA. 4 Department of Ophthalmology, Augusta University, Augusta, GA, USA
| | - Todd A Lydic
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Shailendra Giri
- Department of Neurology, Henry Ford Health System, Detroit, MI, USA
| | - Ashok Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences/ Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, USA.
| |
Collapse
|
3
|
Li HY, Huang LF, Huang XR, Wu D, Chen XC, Tang JX, An N, Liu HF, Yang C. Endoplasmic Reticulum Stress in Systemic Lupus Erythematosus and Lupus Nephritis: Potential Therapeutic Target. J Immunol Res 2023; 2023:7625817. [PMID: 37692838 PMCID: PMC10484658 DOI: 10.1155/2023/7625817] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 07/20/2023] [Accepted: 08/10/2023] [Indexed: 09/12/2023] Open
Abstract
Systemic lupus erythematosus (SLE) is a complex autoimmune disease. Approximately one-third to two-thirds of the patients with SLE progress to lupus nephritis (LN). The pathogenesis of SLE and LN has not yet been fully elucidated, and effective treatment for both conditions is lacking. The endoplasmic reticulum (ER) is the largest intracellular organelle and is a site of protein synthesis, lipid metabolism, and calcium storage. Under stress, the function of ER is disrupted, and the accumulation of unfolded or misfolded proteins occurs in ER, resulting in an ER stress (ERS) response. ERS is involved in the dysfunction of B cells, macrophages, T cells, dendritic cells, neutrophils, and other immune cells, causing immune system disorders, such as SLE. In addition, ERS is also involved in renal resident cell injury and contributes to the progression of LN. The molecular chaperones, autophagy, and proteasome degradation pathways inhibit ERS and restore ER homeostasis to improve the dysfunction of immune cells and renal resident cell injury. This may be a therapeutic strategy for SLE and LN. In this review, we summarize advances in this field.
Collapse
Affiliation(s)
- Hui-Yuan Li
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Li-Feng Huang
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Xiao-Rong Huang
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Dan Wu
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Xiao-Cui Chen
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Ji-Xin Tang
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Ning An
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Hua-Feng Liu
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| | - Chen Yang
- Guangdong Provincial Key Laboratory of Autophagy and Major Chronic Non-communicable Diseases, Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong 524001, China
| |
Collapse
|
4
|
Huang Z, Zheng X, Chen Z, Zheng Z, Yao D, Yang S, Zhang Y, Aweya JJ. Modulation of SREBP Expression and Fatty Acid Levels by Bacteria-Induced ER Stress Is Mediated by Hemocyanin in Penaeid Shrimp. Mar Drugs 2023; 21:md21030164. [PMID: 36976213 PMCID: PMC10055750 DOI: 10.3390/md21030164] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 02/23/2023] [Accepted: 02/26/2023] [Indexed: 03/06/2023] Open
Abstract
Many environmental and pathogenic insults induce endoplasmic reticulum (ER) stress in animals, especially in aquatic ecosystems, where these factors are crucial for life. In penaeid shrimp, pathogens and environmental stressors induce hemocyanin expression, but the involvement of hemocyanin in ER stress response is unknown. We demonstrate that in response to pathogenic bacteria (Vibrio parahaemolyticus and Streptococcus iniae), hemocyanin, ER stress proteins (Bip, Xbp1s, and Chop), and sterol regulatory element binding protein (SREBP) are induced to alter fatty acid levels in Penaeus vannamei. Interestingly, hemocyanin interacts with ER stress proteins to modulate SREBP expression, while ER stress inhibition with 4-Phenylbutyric acid or hemocyanin knockdown attenuates the expression of ER stress proteins, SREBP, and fatty acid levels. Contrarily, hemocyanin knockdown followed by tunicamycin treatment (ER stress activator) increased their expression. Thus, hemocyanin mediates ER stress during pathogen challenge, which consequently modulates SREBP to regulate the expression of downstream lipogenic genes and fatty acid levels. Our findings reveal a novel mechanism employed by penaeid shrimp to counteract pathogen-induced ER stress.
Collapse
Affiliation(s)
- Zishu Huang
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Xiaoyu Zheng
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Zeyan Chen
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Zhihong Zheng
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Defu Yao
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
| | - Shen Yang
- Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China
| | - Yueling Zhang
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
- Correspondence: (Y.Z.); (J.J.A.); Tel.: +86-13615050594 (J.J.A.); +86-754-86502580 (Y.L.Z.)
| | - Jude Juventus Aweya
- Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou 515063, China
- Correspondence: (Y.Z.); (J.J.A.); Tel.: +86-13615050594 (J.J.A.); +86-754-86502580 (Y.L.Z.)
| |
Collapse
|
5
|
Zhao XQ, Wan HY, He SY, Qin HJ, Yu B, Jiang N. Vitamin D Receptor Genetic Polymorphisms Associate With a Decreased Susceptibility to Extremity Osteomyelitis Partly by Inhibiting Macrophage Apoptosis Through Inhibition of Excessive ROS Production via VDR-Bmi1 Signaling. Front Physiol 2022; 13:808272. [PMID: 35957979 PMCID: PMC9359620 DOI: 10.3389/fphys.2022.808272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 06/24/2022] [Indexed: 11/24/2022] Open
Abstract
Background: Previous studies had reported that vitamin D receptor (VDR) gene polymorphisms were related to the development of several inflammatory disorders. However, potential links between such variations and the risk of developing a bone infection and underlying mechanisms remain unclear. This study aimed to analyze potential associations between VDR genetic variations and susceptibility to extremity osteomyelitis (OM) in a Chinese Han population and investigate potential mechanisms. Methods: Between January 2016 and August 2020, altogether 398 OM patients and 368 healthy controls were genotyped for six VDR gene polymorphisms, including ApaI (rs7975232), BsmI (rs1544410), FokI (rs2228570), TaqI (rs731236), GATA (rs4516035), and Cdx-2 (rs11568820) by the SNaPshot genotyping method. Then, male C57BL/6 mice were randomly divided into vitamin D–standard, –excess, –deficient, and –rescued groups. One week after making the model surgery, OM occurrence and severity were assessed using the bacterial count and histopathological staining. In vitro, phagocytosis, apoptosis, and bactericidal ability of macrophages were evaluated by overexpression or knockdown of VDR protein. Results: Significant associations were found among rs7975232, rs1544410, and OM development by the recessive model (AA vs. AC + CC, p = 0.037, OR = 0.594), homozygous model (AA vs. CC, p = 0.033, OR = 0.575), and heterozygous model (CT vs. CC, p = 0.049, OR = 0.610), respectively. Patients with the AA genotype of rs7975232 had a relatively higher mean level of vitamin D than those with AC and CC genotypes (22.5 vs. 20.7 vs. 19.0 ng/ml). Similarly, patients with CT genotype of rs1544410 had a relatively higher mean vitamin D level than those with CC genotype (20.94 vs. 19.89 ng/ml). Outcomes of in vivo experiments showed that the femoral bacterial load of vitamin D–deficient mice was highest among different vitamin D dose groups, with the most severe histopathological features of infection, and vitamin D supplementation partly reversed the changes. While in vitro experiment results revealed that active vitamin D promoted phagocytosis and sterilization of macrophages and inhibited apoptosis during infection. Reactive oxygen species (ROS) inhibitor inhibited apoptosis of macrophages induced by bacterial infection. Active vitamin D inhibited excessive ROS production in macrophages via the VDR-Bmi1 signaling pathway. Conclusion: In this Chinese cohort, ApaI and BsmI are associated with a decreased risk of OM development by influencing serological vitamin D level, the latter of which reduced macrophage apoptosis with inhibition of excessive ROS production via the VDR-Bmi1 signaling pathway.
Collapse
Affiliation(s)
- Xing-Qi Zhao
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
| | - Hao-Yang Wan
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
| | - Si-Ying He
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
| | - Han-Jun Qin
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
| | - Bin Yu
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
- *Correspondence: Bin Yu, , orcid.org/0000-0002-3109-2062; Nan Jiang, , orcid.org/0000-0003-2416-1653
| | - Nan Jiang
- Division of Orthopaedics and Traumatology, Department of Orthopaedics, Southern Medical University Nanfang Hospital, Guangzhou, China
- Guangdong Provincial Key Laboratory of Bone and Cartilage Regenerative Medicine, Southern Medical University Nanfang Hospital, Guangzhou, China
- *Correspondence: Bin Yu, , orcid.org/0000-0002-3109-2062; Nan Jiang, , orcid.org/0000-0003-2416-1653
| |
Collapse
|
6
|
Essential Role of NLRP3 Inflammasome in Mediating IL-1β Production and the Pathobiology of Staphylococcus aureus Endophthalmitis. Infect Immun 2022; 90:e0010322. [PMID: 35404106 DOI: 10.1128/iai.00103-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Staphylococcal endophthalmitis is one of the leading causes of blindness following ocular surgery and trauma. Dysregulated inflammation during bacterial endophthalmitis causes host-induced inflammatory damage and vision loss if it remains unchecked. Emerging evidence indicates that inflammasome plays a critical role in regulating innate immunity in various infectious and inflammatory diseases. However, the role of the inflammasome in endophthalmitis remains elusive. Here, using a mouse model of Staphylococcus (S) aureus endophthalmitis, we show that NLRP3/ASC/Caspase-1 signaling regulates IL-1β production in endophthalmitis. We also show that S. aureus and its cell wall components and toxins induce the activation of the NLRP3 inflammasome complex in mouse eyes. Moreover, we found that both infiltrating neutrophils and retinal microglia contribute toward NLRP3 activation and IL-1β production in S. aureus-infected eyes. Furthermore, our data using NLRP3-/- and IL-1β-/- mice revealed that NLRP3 and IL-1β deficiency leads to increased intraocular bacterial burden and retinal tissue damage. Altogether, our study demonstrated an essential role of NLRP3 inflammasome activation in regulating innate immune responses in bacterial endophthalmitis.
Collapse
|
7
|
Staphylococcus aureus Induces Goat Endometrial Epithelial Cells Apoptosis via the Autophagy and Endoplasmic Reticulum Stress Pathway. Animals (Basel) 2022; 12:ani12060711. [PMID: 35327108 PMCID: PMC8944437 DOI: 10.3390/ani12060711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/02/2022] [Accepted: 03/08/2022] [Indexed: 01/08/2023] Open
Abstract
Simple Summary The toxicity mechanism of Staphylococcus aureus on goat endometrial epithelial cells (gEECs) is still unelucidated. The purpose of this experiment was to investigate the molecular mechanism of gEECs death caused by S. aureus in terms of autophagy and endoplasmic reticulum (ER) stress. We found that the accumulation of autophagosomes exacerbated S. aureus-induced gEECs apoptosis, and that ER stress was involved in the regulation of the autophagy. These findings may provide new insight into the therapeutic target of endometrial cell injury. Abstract Increasing evidence indicates that autophagy and endoplasmic reticulum (ER) stress are involved in the regulation of cell death; however, the role of autophagy and ER stress in Staphylococcus aureus-induced endometrial epithelial cell damage is still unelucidated. In the present study, our results showed that infection with S. aureus increased the cytotoxicity and the protein expression of Bax, caspase-3, and cleaved-PARP-1 in goat endometrial epithelial cells (gEECs). Moreover, after infection, the expression of LC3II and autophagosomes were markedly increased. The autophagosome inhibitor 3-methyladenine (3-MA) significantly decreased the cytotoxicity and the expression of caspase-3, and cleaved-PARP-1; however, the autophagosome–lysosome fusion inhibitor chloroquine (CQ) increased their expression. Additionally, the protein expression of GRP78, EIF2α, and ATF4 were also markedly increased after infection. The ER stress inhibitor 4-PBA decreased the cytotoxicity and the expression of LC3II and apoptosis-related proteins in S. aureus-infected gEECs. Collectively, our findings prove that the accumulation of autophagosomes exacerbated S. aureus-induced gEECs apoptosis, and that ER stress was involved in the regulation of the autophagy and apoptosis.
Collapse
|
8
|
Das S, Singh S, Kumar A. Bacterial Burden Declines But Neutrophil Infiltration and Ocular Tissue Damage Persist in Experimental Staphylococcus epidermidis Endophthalmitis. Front Cell Infect Microbiol 2021; 11:780648. [PMID: 34869079 PMCID: PMC8635919 DOI: 10.3389/fcimb.2021.780648] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 10/25/2021] [Indexed: 01/01/2023] Open
Abstract
Coagulase-negative staphylococci (CoNS), including Staphylococcus (S) epidermidis, are responsible for ~70% of all post-surgical endophthalmitis, a potentially blinding eye infection. However, the pathobiology of CoNS endophthalmitis is limited to epidemiological and clinical case studies with few experimental studies. Here, we report both in vitro and in vivo models to study the pathobiology of S. epidermidis endophthalmitis in mice. We found that S. epidermidis is rapidly cleared from mouse eyes, and a relatively higher dose (i.e., 107 CFU/eye) was needed to cause endophthalmitis. Our time-course study revealed that bacterial load peaked at 24 h post-infection followed by a gradual decline up to 72 h. A similar time-dependent decrease in levels of inflammatory mediators and Toll-like receptor (TLR) expression was also observed. In contrast, neutrophil infiltration continued to increase up to 72 h coinciding with significant retinal tissue damage and loss of visual function. In vitro, S. epidermidis induced the activation of various inflammatory signaling pathways (i.e., NF-kB, ERK, and P38) and the production of both cytokines and chemokines in mouse BMDMs, human RPE, and retinal Muller glia. Altogether, we show that bacterial burden is reduced in S. epidermidis endophthalmitis, while tissue damage and visual function loss continue. Thus, our study provides new insights into the pathogenesis of CoNS endophthalmitis.
Collapse
Affiliation(s)
- Susmita Das
- Department of Ophthalmology, Visual and Anatomical Sciences/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, United States
| | - Sukhvinder Singh
- Department of Ophthalmology, Visual and Anatomical Sciences/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, United States
| | - Ashok Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, United States
| |
Collapse
|
9
|
Comparison of structural components and functional mechanisms within the skin vs. the conjunctival surface. Curr Opin Allergy Clin Immunol 2021; 21:472-479. [PMID: 34387279 DOI: 10.1097/aci.0000000000000775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE OF REVIEW The purpose of this review is to highlight and compare the structural and functional differences between the ocular surface and the skin. The goal is to further understand how these components interact from an immunobiological standpoint, which may inform future therapeutic uses. RECENT FINDINGS Treatment agents, such as Dupilumab and Apremilast are traditionally indicated for integumentary conditions, such as atopic dermatitis and psoriasis, respectively. Both were also found to have potent effects on the conjunctival surface and ocular glands, which may be attributed to the similarities in structure. SUMMARY Surfaces of the eyes and the skin are found to have similar composition in terms of immunohistology, steroidogenic properties, and allergic mechanisms. These translate directly into both the adverse effects and therapeutic benefits that overlap when treating these surfaces.
Collapse
|
10
|
Singh S, Singh PK, Jha A, Naik P, Joseph J, Giri S, Kumar A. Integrative metabolomics and transcriptomics identifies itaconate as an adjunct therapy to treat ocular bacterial infection. Cell Rep Med 2021; 2:100277. [PMID: 34095879 PMCID: PMC8149370 DOI: 10.1016/j.xcrm.2021.100277] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 12/13/2020] [Accepted: 04/19/2021] [Indexed: 12/20/2022]
Abstract
The eye is highly susceptible to inflammation-mediated tissue damage evoked during bacterial infection. However, mechanisms regulating inflammation to protect the eye remain elusive. Here, we used integrated metabolomics and transcriptomics to show that the immunomodulatory metabolite itaconate and immune-responsive gene 1 (Irg1) are induced in bacterial (Staphylococcus aureus)-infected mouse eyes, bone-marrow-derived macrophages (BMDMs), and Müller glia. Itaconate levels are also elevated in the vitreous of patients with bacterial endophthalmitis. Irg1 deficiency in mice led to increased ocular pathology. Conversely, intraocular administration of itaconate protects both Irg1-/- and wild-type mice from bacterial endophthalmitis by reducing inflammation, bacterial burden, and preserving retinal architecture and visual function. Notably, itaconate exerts synergistic effects with antibiotics. The protective, anti-inflammatory effects of itaconate are mediated via activation of NRF2/HO-1 signaling and inhibition of NLRP3 inflammasome. Collectively, our study demonstrates the Irg1/itaconate axis is a regulator of intraocular inflammation and provides evidence for using itaconate, along with antibiotics, to treat bacterial infections.
Collapse
Affiliation(s)
- Sukhvinder Singh
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Pawan Kumar Singh
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Alokkumar Jha
- Cardiovascular Institute, Stanford University, Stanford, CA, USA
- Stanford Cancer Institute, Stanford University, CA, USA
| | | | | | - Shailendra Giri
- Department of Neurology, Henry Ford Health System, Detroit, MI, USA
| | - Ashok Kumar
- Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, USA
| |
Collapse
|
11
|
Zhang F, Jia D, Li Q, Zhang M, Liu H, Wu X. Preparation and Evaluation of a Xanthan Gum-Containing Linezolid Ophthalmic Solution for Topical Treatment of Experimental Bacterial Keratitis. Pharm Res 2021; 38:347-359. [PMID: 33469875 DOI: 10.1007/s11095-020-02982-x] [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] [Received: 10/12/2020] [Accepted: 12/22/2020] [Indexed: 11/28/2022]
Abstract
PURPOSE To formulate a xanthan gum-containing linezolid ophthalmic solution (LZD-XG) as a new antibiotic treatment against ocular bacterial infection. METHODS LZD-XG was prepared and evaluated for its in vitro/in vivo ocular tolerance, in vitro/in vivo antibacterial activity, and in vivo ocular penetration. RESULTS The optimized LZD-XG exhibited good in vitro/in vivo eye tolerance. A prolonged ocular surface residence time of LZD-XG was observed after topical instillation, and the ocular permeation was significantly better for LZD-XG than fora linezolid (LZD) ophthalmic solution. The in vitro antimicrobial activity was significantly better with LZD-XG than with LZD. In vivo evaluation also confirmed a strong therapeutic treatment effect of LZD-XG, as it significantly improved the clinical symptoms, ameliorated the damage of Staphylococcus aureus to ocular tissues, lowered the colony forming unit counts in the cornea, and decreased the myeloperoxidase activity in the cornea. CONCLUSION LZD-XG was deemed a viable ophthalmic solution against ocular bacterial infection due to its excellent in vitro and in vivo characterizations.
Collapse
Affiliation(s)
- Fan Zhang
- Department of Pharmacy, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Dongmei Jia
- Department of Pathology, Qingdao Municipal Hospital, Qingdao, 266011, China
| | - Qiqi Li
- Department of Pharmacy, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Mengmeng Zhang
- Department of Pathology, Qingdao Municipal Hospital, Qingdao, 266011, China
| | - Hongyun Liu
- Department of Pathology, Qingdao Municipal Hospital, Qingdao, 266011, China.
| | - Xianggen Wu
- Department of Pharmacy, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
| |
Collapse
|