1
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Dawson LW, Cronin NM, DeMali KA. Mechanotransduction: Forcing a change in metabolism. Curr Opin Cell Biol 2023; 84:102219. [PMID: 37651955 PMCID: PMC10523412 DOI: 10.1016/j.ceb.2023.102219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 09/02/2023]
Abstract
Epithelial and endothelial cells experience numerous mechanical cues throughout their lifetimes. Cells resist these forces by fortifying their cytoskeletal networks and adhesions. This reinforcement is energetically costly. Here we describe how these energetic demands are met. We focus on the response of epithelial and endothelial cells to mechanical cues, describe the energetic needs of epithelia and endothelia, and identify the mechanisms these cells employ to increase glycolysis, oxidative phosphorylation, and fatty acid metabolism. We discuss the similarities and differences in the responses of the two cell types.
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Affiliation(s)
- Logan W Dawson
- Department of Biochemistry and Molecular Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Nicholas M Cronin
- Department of Biochemistry and Molecular Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Kris A DeMali
- Department of Biochemistry and Molecular Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
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2
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Enichen E, Adams RB, Demmig-Adams B. Physical Activity as an Adjunct Treatment for People Living with HIV? Am J Lifestyle Med 2023; 17:502-517. [PMID: 37426740 PMCID: PMC10328202 DOI: 10.1177/15598276221078222] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023] Open
Abstract
This review evaluates physical activity as a candidate for an adjunct treatment, in conjunction with antiretroviral therapy (ART), for people living with HIV (PLWH). Evidence is summarized that chronic, non-resolving inflammation (a principal feature of immune system dysfunction) and a dysfunctional state of the gut environment are key factors in HIV infection that persist despite treatment with ART. In addition, evidence is summarized that regular physical activity may restore normal function of both the immune system and the gut environment and may thereby ameliorate symptoms and non-resolving inflammation-associated comorbidities that burden PLWH. Physicians who care for PLWH could thus consider incorporating physical activity into treatment plans to complement ART. It is also discussed that different types of physical activity can have different effects on the gut environment and immune function, and that future research should establish more specific criteria for the design of exercise regimens tailored to PLWH.
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Affiliation(s)
- Elizabeth Enichen
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA, (EE, BDA); Physical Therapy of Boulder, Boulder, CO, USA, (RBA)
| | - Robert B. Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA, (EE, BDA); Physical Therapy of Boulder, Boulder, CO, USA, (RBA)
| | - Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA, (EE, BDA); Physical Therapy of Boulder, Boulder, CO, USA, (RBA)
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3
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Montagnani M, Bottalico L, Potenza MA, Charitos IA, Topi S, Colella M, Santacroce L. The Crosstalk between Gut Microbiota and Nervous System: A Bidirectional Interaction between Microorganisms and Metabolome. Int J Mol Sci 2023; 24:10322. [PMID: 37373470 DOI: 10.3390/ijms241210322] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
Several studies have shown that the gut microbiota influences behavior and, in turn, changes in the immune system associated with symptoms of depression or anxiety disorder may be mirrored by corresponding changes in the gut microbiota. Although the composition/function of the intestinal microbiota appears to affect the central nervous system (CNS) activities through multiple mechanisms, accurate epidemiological evidence that clearly explains the connection between the CNS pathology and the intestinal dysbiosis is not yet available. The enteric nervous system (ENS) is a separate branch of the autonomic nervous system (ANS) and the largest part of the peripheral nervous system (PNS). It is composed of a vast and complex network of neurons which communicate via several neuromodulators and neurotransmitters, like those found in the CNS. Interestingly, despite its tight connections to both the PNS and ANS, the ENS is also capable of some independent activities. This concept, together with the suggested role played by intestinal microorganisms and the metabolome in the onset and progression of CNS neurological (neurodegenerative, autoimmune) and psychopathological (depression, anxiety disorders, autism) diseases, explains the large number of investigations exploring the functional role and the physiopathological implications of the gut microbiota/brain axis.
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Affiliation(s)
- Monica Montagnani
- Department of Precision and Regenerative Medicine and Ionian Area-Section of Pharmacology, School of Medicine, University of Bari "Aldo Moro", Policlinico University Hospital of Bari, Piazza G. Cesare 11, 70124 Bari, Italy
| | - Lucrezia Bottalico
- School of Technical Medical Sciences, "Alexander Xhuvani" University of Elbasan, 3001-3006 Elbasan, Albania
| | - Maria Assunta Potenza
- Department of Precision and Regenerative Medicine and Ionian Area-Section of Pharmacology, School of Medicine, University of Bari "Aldo Moro", Policlinico University Hospital of Bari, Piazza G. Cesare 11, 70124 Bari, Italy
| | - Ioannis Alexandros Charitos
- Pneumology and Respiratory Rehabilitation Division, Maugeri Clinical Scientific Research Institutes (IRCCS), 70124 Bari, Italy
| | - Skender Topi
- School of Technical Medical Sciences, "Alexander Xhuvani" University of Elbasan, 3001-3006 Elbasan, Albania
| | - Marica Colella
- Interdisciplinary Department of Medicine, Microbiology and Virology Unit, School of Medicine, University of Bari "Aldo Moro", Piazza G. Cesare, 11, 70124 Bari, Italy
| | - Luigi Santacroce
- Interdisciplinary Department of Medicine, Microbiology and Virology Unit, School of Medicine, University of Bari "Aldo Moro", Piazza G. Cesare, 11, 70124 Bari, Italy
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4
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Ganji N, Biouss G, Sabbatini S, Li B, Lee C, Pierro A. Remote ischemic conditioning in necrotizing enterocolitis. Semin Pediatr Surg 2023; 32:151312. [PMID: 37295298 DOI: 10.1016/j.sempedsurg.2023.151312] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Necrotizing enterocolitis (NEC) is a devastating intestinal inflammatory disorder, most prevalent in premature infants, and associated with a high mortality rate that has remained unchanged in the past two decades. NEC is characterized by inflammation, ischemia, and impaired microcirculation in the intestine. Preclinical studies by our group have led to the discovery of remote ischemic conditioning (RIC) as a promising non-invasive intervention in protecting the intestine against ischemia-induced damage during early-stage NEC. RIC involves the administration of brief reversible cycles of ischemia and reperfusion in a limb (similar to taking standard blood pressure measurement) which activate endogenous protective signaling pathways that are conveyed to distant organs such as the intestine. RIC targets the intestinal microcirculation and by improving blood flow to the intestine, reduces the intestinal damage of experimental NEC and prolongs survival. A recent Phase I safety study by our group demonstrated that RIC was safe in preterm infants with NEC. A phase II feasibility randomized controlled trial involving 12 centers in 6 countries is currently underway, to investigate the feasibility of RIC as a treatment for early-stage NEC in preterm neonates. This review provides a brief background on RIC as a therapeutic strategy and summarizes the progression of RIC as a treatment for NEC from preclinical investigation to clinical evaluation.
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Affiliation(s)
- Niloofar Ganji
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada; Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - George Biouss
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada; Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Stella Sabbatini
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Bo Li
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Carol Lee
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Agostino Pierro
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada; Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada; Division of General and Thoracic Surgery, The Hospital for Sick Children, University of Toronto, 1526-555 University Ave, Toronto, ON M5G 1×8, Canada.
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5
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Ganji N, Li B, Lee C, Pierro A. Necrotizing enterocolitis: recent advances in treatment with translational potential. Pediatr Surg Int 2023; 39:205. [PMID: 37247104 DOI: 10.1007/s00383-023-05476-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/19/2023] [Indexed: 05/30/2023]
Abstract
Necrotizing enterocolitis (NEC) is one of the most prevalent and devastating gastrointestinal disorders in neonates. Despite advances in neonatal care, the incidence and mortality due to NEC remain high, highlighting the need to devise novel treatments for this disease. There have been a number of recent advancements in therapeutic approaches for the treatment of NEC; these involve remote ischemic conditioning (RIC), stem cell therapy, breast milk components (human milk oligosaccharides, exosomes, lactoferrin), fecal microbiota transplantation, and immunotherapy. This review summarizes the most recent advances in NEC treatment currently underway as well as their applicability and associated challenges and limitations, with the aim to provide new insight into the paradigm of care for NEC worldwide.
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Affiliation(s)
- Niloofar Ganji
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Bo Li
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Carol Lee
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
| | - Agostino Pierro
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
- Translational Medicine, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada.
- Division of General and Thoracic Surgery, The Hospital for Sick Children, University of Toronto, 1526-555 University Ave, Toronto, ON, M5G 1X8, Canada.
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6
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Jung EH, Brauner CJ, Wood CM. Do extreme postprandial levels of oxygen, carbon dioxide, and ammonia in the digestive tract equilibrate with the bloodstream in the freshwater rainbow trout (Oncorhynchus mykiss)? J Comp Physiol B 2023; 193:193-205. [PMID: 36656334 DOI: 10.1007/s00360-023-01475-8] [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: 02/18/2022] [Revised: 12/20/2022] [Accepted: 01/06/2023] [Indexed: 01/20/2023]
Abstract
The gastrointestinal tract (GIT) lumen of teleosts harbors extreme conditions, especially after feeding: high PCO2 (20-115 Torr), total ammonia (415-3710 μM), PNH3 (79-1760 μTorr in the intestine), and virtual anoxia (PO2 < 1 Torr). These levels could be dangerous if they were to equilibrate with the bloodstream. Thus, we investigated the potential equilibration of O2, CO2, and ammonia across the GIT epithelia in freshwater rainbow trout by monitoring postprandial arterial and venous blood gases in vivo and in situ. In vivo blood was sampled from the indwelling catheters in the dorsal aorta (DA) and subintestinal vein (SIV) draining the posterior intestine in the fasting state and at 4 to 48 h following catheter-feeding. To investigate possible ammonia absorption in the anterior part of the GIT, blood was sampled from the DA, SIV and hepatic portal vein (HPV) from anaesthetized fish in situ following voluntary feeding. We found minimal equilibration of all three gases between the GIT lumen and the SIV blood, with the latter maintaining pre-feeding levels (PO2 = 25-49 Torr, PCO2 = 6-8 Torr, and total ammonia = 117-134 μM and PNH3 = 13-30 μTorr at 48 h post-feeding). In contrast to the SIV, we found that the HPV total ammonia more than doubled 24 h after feeding (128 to 297 μM), indicative of absorption in the anterior GIT. Overall, the GIT epithelia of trout, although specialized for absorption, prevent dangerous levels of PO2, PCO2 and ammonia from equilibrating with the blood circulation.
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Affiliation(s)
- Ellen H Jung
- Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
| | - Colin J Brauner
- Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Chris M Wood
- Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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7
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Han Y, Liu X, Kang L, Chen D, Li Y, Zhang H, Sun M, Gao H, Gai Z, Li X. A potential pathogenic hypoxia-related gene HK2 in necrotizing enterocolitis (NEC) of newborns. BMC Pediatr 2022; 22:617. [PMID: 36289463 PMCID: PMC9597967 DOI: 10.1186/s12887-022-03664-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 09/30/2022] [Indexed: 12/05/2022] Open
Abstract
Background Necrotizing enterocolitis (NEC) is a disastrous gastrointestinal disease of newborns, and the mortality rate of infants with NEC is approximately 20%-30%. The exploration of pathogenic targets of NEC will be conducive to timely diagnosis of NEC. Methods The whole transcriptome RNA sequencing was performed on NEC samples to reveal the expression of lncRNAs, circRNAs, miRNAs and mRNAs. Using differential expression analysis, cross analysis, target prediction, enrichment analysis, the pathogenic ceRNA network and target was found. Results Preliminarily, 281 DEmRNAs, 21 DEmiRNAs, 253 DElncRNAs and 207 DEcircRNAs were identified in NEC samples compared with controls. After target prediction and cross analyses, a key ceRNA regulatory network was built including 2 lncRNAs, 4 circRNAs, 2 miRNAs and 20 mRNAs. These 20 mRNAs were significantly enriched in many carbohydrate metabolism related pathways. After cross analysis of hypoxia-, carbohydrate metabolism-related genes, and 20 core genes, one gene HK2 was finally obtained. Dendritic cells activated were significantly differentially infiltrated and negatively correlated with HK2 expression in NEC samples. Conclusions The promising pathogenic hypoxia-related gene HK2 has been firstly identified in NEC, which might also involve in the carbohydrate metabolism in NEC. Supplementary Information The online version contains supplementary material available at 10.1186/s12887-022-03664-w.
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Affiliation(s)
- Yujie Han
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Xianghong Liu
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Lili Kang
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Dong Chen
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Yongqing Li
- Department of Neonatal, LaoLing Maternity and Child Health Care Hospital, 118 Anju Road, Laoling County, Dezhou, Shandong Province, 253600 People’s Republic of China
| | - Huiping Zhang
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Mingying Sun
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Hui Gao
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Zhongtao Gai
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
| | - Xiaoying Li
- grid.27255.370000 0004 1761 1174Department of Neonatal, Children’s Hospital Affiliated to Shandong University/Jinan Children’s Hospital, No. 23976 Huaiyin District, Jinan, 250022 Shandong, People’s Republic of China
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8
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Chen Y, Rudolph S, Longo BN, Pace F, Roh T, Condruti R, Gee M, Watnick P, Kaplan DL. Bioengineered 3D Tissue Model of Intestine Epithelium with Oxygen Gradients to Sustain Human Gut Microbiome. Adv Healthc Mater 2022; 11:e2200447. [PMID: 35686484 PMCID: PMC9388577 DOI: 10.1002/adhm.202200447] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 05/25/2022] [Indexed: 01/24/2023]
Abstract
The human gut microbiome is crucial to hosting physiology and health. Therefore, stable in vitro coculture of primary human intestinal cells with a microbiome community is essential for understanding intestinal disease progression and revealing novel therapeutic targets. Here, a three-dimensional scaffold system is presented to regenerate an in vitro human intestinal epithelium that recapitulates many functional characteristics of the native small intestines. The epithelium, derived from human intestinal enteroids, contains mature intestinal epithelial cells and possesses selectively permeable barrier functions. Importantly, by properly positioning the scaffolds cultured under normal atmospheric conditions, two physiologically relevant oxygen gradients, a proximal-to-distal oxygen gradient along the gastrointestinal (GI) tract, and a radial oxygen gradient across the epithelium, are distinguished in the tissues when the lumens are faced up and down in cultures, respectively. Furthermore, the presence of the low oxygen gradients supported the coculture of intestinal epithelium along with a complex living commensal gut microbiome (including obligate anaerobes) to simulate temporal microbiome dynamics in the native human gut. This unique silk scaffold platform may enable the exploration of microbiota-related mechanisms of disease pathogenesis and host-pathogen dynamics in infectious diseases including the potential to explore the human microbiome-gut-brain axis and potential novel microbiome-based therapeutics.
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Affiliation(s)
- Ying Chen
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA,To whom correspondence may be addressed. ;
| | - Sara Rudolph
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA
| | - Brooke N. Longo
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA
| | - Fernanda Pace
- Division of Infectious Diseases, Boston Children’s Hospital, 300 Longwood Avenue, Boston, MA 02115, USA,Department of Pediatrics, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA
| | - Terrence Roh
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA
| | - Rebecca Condruti
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA
| | - Michelle Gee
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA
| | - Paula Watnick
- Division of Infectious Diseases, Boston Children’s Hospital, 300 Longwood Avenue, Boston, MA 02115, USA,Department of Pediatrics, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA
| | - David L. Kaplan
- Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, USA,Division of Infectious Diseases, Boston Children’s Hospital, 300 Longwood Avenue, Boston, MA 02115, USA,To whom correspondence may be addressed. ;
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9
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Wu Z, Xu C, Zheng T, Li Q, Yang S, Shao J, Guan W, Zhang S. A critical role of AMP-activated protein kinase in regulating intestinal nutrient absorption, barrier function, and intestinal diseases. J Cell Physiol 2022; 237:3705-3716. [PMID: 35892164 DOI: 10.1002/jcp.30841] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/12/2022] [Accepted: 07/15/2022] [Indexed: 02/06/2023]
Abstract
As one of the most important organs in animals, the intestine is responsible for nutrient absorption and acts as a barrier between the body and the environment. Intestinal physiology and function require the participation of energy. 5'-adenosine monophosphate-activated protein kinase (AMPK), a classical and highly expressed energy regulator in intestinal cells, regulates the process of nutrient absorption and barrier function and is also involved in the therapy of intestinal diseases. Studies have yielded findings that AMPK regulates the absorption of glucose, amino acids, and fatty acids in the intestine primarily by regulating transportation systems, as we detailed here. Moreover, AMPK is involved in the regulation of the intestinal mechanical barrier and immune barrier through manipulating the expression of tight junctions, antimicrobial peptides, and secretory immunoglobulins. In addition, AMPK also participates in the regulation of intestinal diseases, which indicates that AMPK is a promising therapeutic target for intestinal diseases and cancer. In this review, we summarized the current understanding regarding how AMPK regulates intestinal nutrient absorption, barrier function, and intestinal diseases.
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Affiliation(s)
- Zhihui Wu
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Chengfei Xu
- School of Clinical Medicine, Chengdu Medical College, Chengdu, China
| | - Tenghui Zheng
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Qihui Li
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Siwang Yang
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Jiayuan Shao
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Wutai Guan
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China.,College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou, China
| | - Shihai Zhang
- Guangdong Province Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, China.,College of Animal Science and National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
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10
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Evolutionary Adaptations of Parasitic Flatworms to Different Oxygen Tensions. Antioxidants (Basel) 2022; 11:antiox11061102. [PMID: 35739999 PMCID: PMC9220675 DOI: 10.3390/antiox11061102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/25/2022] [Accepted: 05/29/2022] [Indexed: 11/17/2022] Open
Abstract
During the evolution of the Earth, the increase in the atmospheric concentration of oxygen gave rise to the development of organisms with aerobic metabolism, which utilized this molecule as the ultimate electron acceptor, whereas other organisms maintained an anaerobic metabolism. Platyhelminthes exhibit both aerobic and anaerobic metabolism depending on the availability of oxygen in their environment and/or due to differential oxygen tensions during certain stages of their life cycle. As these organisms do not have a circulatory system, gas exchange occurs by the passive diffusion through their body wall. Consequently, the flatworms developed several adaptations related to the oxygen gradient that is established between the aerobic tegument and the cellular parenchyma that is mostly anaerobic. Because of the aerobic metabolism, hydrogen peroxide (H2O2) is produced in abundance. Catalase usually scavenges H2O2 in mammals; however, this enzyme is absent in parasitic platyhelminths. Thus, the architecture of the antioxidant systems is different, depending primarily on the superoxide dismutase, glutathione peroxidase, and peroxiredoxin enzymes represented mainly in the tegument. Here, we discuss the adaptations that parasitic flatworms have developed to be able to transit from the different metabolic conditions to those they are exposed to during their life cycle.
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11
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Lian L, Zhou C, Tang G, Xie M, Wang Z, Luo Z, Japo J, Wang D, Zhou J, Wang M, Li W, Maharjan S, Ruelas M, Guo J, Wu X, Zhang YS. Uniaxial and Coaxial Vertical Embedded Extrusion Bioprinting. Adv Healthc Mater 2022; 11:e2102411. [PMID: 34860472 DOI: 10.1002/adhm.202102411] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 11/22/2021] [Indexed: 12/12/2022]
Abstract
The 3D bioprinting technologies have attracted increasing attention due to their flexibility in producing architecturally relevant tissue constructs. Here, a vertical embedded extrusion bioprinting strategy using uniaxial or coaxial nozzles is presented, which allows formation of vertical structures of homogeneous or heterogeneous properties. By adjusting the bioprinting parameters, the characteristics of the bioprinted vertical patterns can be precisely controlled. Using this strategy, two proof-of-concept applications in tissue biofabrication are demonstrated. Specifically, intestinal villi and hair follicles, two liner-shaped tissues in the human body, are successfully generated with the vertical embedded bioprinting method, reconstructing some of their key structures as well as restoring partial functions in vitro. Caco-2 cells in the bioprinted intestinal villus constructs proliferated and aggregated properly, also showing functional biomarker expressions such as ZO-1 and villin. Moreover, preliminary hair follicle structures featuring keratinized human keratinocytes and spheroid-shaped human dermal papilla cells are formed after vertical bioprinting and culturing. In summary, this vertical embedded extrusion bioprinting technique harnessing a uniaxial or coaxial format will likely bring further improvements in the reconstruction of certain human tissues and organs, especially those with a linear structure, potentially leading to wide utilities in tissue engineering, tissue model engineering, and drug discovery.
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Affiliation(s)
- Liming Lian
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Cuiping Zhou
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
- Department of Emergency Nanfang Hospital Southern Medical University Guangzhou 510515 P. R. China
| | - Guosheng Tang
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
- NMPA & Guangdong Key Laboratory of Molecular Target & Clinical Pharmacology State Key Laboratory of Respiratory Disease School of Pharmaceutical Sciences The Fifth Affiliated Hospital Guangzhou Medical University Guangzhou Guangdong 511436 P. R. China
| | - Maobin Xie
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Zixuan Wang
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Zeyu Luo
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Julia Japo
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Di Wang
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Jianhua Zhou
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Mian Wang
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Wanlu Li
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Sushila Maharjan
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Marina Ruelas
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Jie Guo
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
| | - Xunwei Wu
- Cutaneous Biology Research Center Massachusetts General Hospital Harvard Medical School Boston MA 02129 USA
| | - Yu Shrike Zhang
- Division of Engineering in Medicine Department of Medicine Brigham and Women's Hospital Harvard Medical School Cambridge MA 02139 USA
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12
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Keely SJ, Barrett KE. Intestinal secretory mechanisms and diarrhea. Am J Physiol Gastrointest Liver Physiol 2022; 322:G405-G420. [PMID: 35170355 PMCID: PMC8917926 DOI: 10.1152/ajpgi.00316.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 01/31/2023]
Abstract
One of the primary functions of the intestinal epithelium is to transport fluid and electrolytes to and from the luminal contents. Under normal circumstances, absorptive and secretory processes are tightly regulated such that absorption predominates, thereby enabling conservation of the large volumes of water that pass through the intestine each day. However, in conditions of secretory diarrhea, this balance becomes dysregulated, so that fluid secretion, driven primarily by Cl- secretion, overwhelms absorptive capacity, leading to increased loss of water in the stool. Secretory diarrheas are common and include those induced by pathogenic bacteria and viruses, allergens, and disruptions to bile acid homeostasis, or as a side effect of many drugs. Here, we review the cellular and molecular mechanisms by which Cl- and fluid secretion in the intestine are regulated, how these mechanisms become dysregulated in conditions of secretory diarrhea, currently available and emerging therapeutic approaches, and how new strategies to exploit intestinal secretory mechanisms are successfully being used in the treatment of constipation.
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Affiliation(s)
- Stephen J Keely
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin, Ireland
| | - Kim E Barrett
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, Davis, California
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13
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L-ARGININE PREVENTS ISCHEMIC INJURY IN EXPLANTED RAT INTESTINAL REGIONS IN AN EX VIVO PERFUSION MODEL. TRANSPLANTATION REPORTS 2022. [DOI: 10.1016/j.tpr.2022.100096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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14
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Ananda Rao A, Johncy S. Tennis Courts in the Human Body: A Review of the Misleading Metaphor in Medical Literature. Cureus 2022; 14:e21474. [PMID: 35223255 PMCID: PMC8863270 DOI: 10.7759/cureus.21474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2022] [Indexed: 12/05/2022] Open
Abstract
Medical literature is home to fancy descriptions, poetic metaphors, and ingenious comparisons. However, some comparisons can disguise the knowledge gap. Large surfaces in the human body, like the alveolar surface for gas exchange, villi for food absorption, and the endothelial lining of blood vessels, are frequently compared to a “tennis court.” This narrative review explores this metaphor in detail, the discrepancies and factual inaccuracies across medical literature. It highlights the inappropriate use of Euclidean geometry and introduces fractal geometry, a language to define roughness.
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15
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Li M, Tian X, Li X, Huang M, Huang S, Wu Y, Jiang M, Shi Y, Shi L, Wang Z. Diverse energy metabolism patterns in females in Neodon fuscus, Lasiopodomys brandtii, and Mus musculus revealed by comparative transcriptomics under hypoxic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 783:147130. [PMID: 34088150 DOI: 10.1016/j.scitotenv.2021.147130] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 03/28/2021] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
The effects of global warming and anthropogenic disturbance force animals to migrate from lower to higher elevations to find suitable new habitats. As such migrations increase hypoxic stress on the animals, it is important to understand how plateau- and plain-dwelling animals respond to low-oxygen environments. We used comparative transcriptomics to explore the response of Neodon fuscus, Lasiopodomys brandtii, and Mus musculus skeletal muscle tissues to hypoxic conditions. Results indicate that these species have adopted different oxygen transport and energy metabolism strategies for dealing with a hypoxic environment. N. fuscus promotes oxygen transport by increasing hemoglobin synthesis and reduces the risk of thrombosis through cooperative regulation of genes, including Fga, Fgb, Alb, and Ttr; genes such as Acs16, Gpat4, and Ndufb7 are involved in regulating lipid synthesis, fatty acid β-oxidation, hemoglobin synthesis, and electron-linked transmission, thereby maintaining a normal energy supply in hypoxic conditions. In contrast, the oxygen-carrying capacity and angiogenesis of red blood cells in L. brandtii are promoted by genes in the CYP and COL families; this species maintains its bodily energy supply by enhancing the pentose phosphate pathway and mitochondrial fatty acid synthesis pathway. However, under hypoxia, M. musculus cannot effectively transport additional oxygen; thus, its cell cycle, proliferation, and migration are somewhat affected. Given its lack of hypoxic tolerance experience, M. musculus also shows significantly reduced oxidative phosphorylation levels under hypoxic conditions. Our results suggest that the glucose capacity of M. musculus skeletal muscle does not provide sufficient energy during hypoxia; thus, we hypothesize that it supplements its bodily energy by synthesizing ketone bodies. For the first time, we describe the energy metabolism pathways of N. fuscus and L. brandtii skeletal muscle tissues under hypoxic conditions. Our findings, therefore, improve our understanding of how vertebrates thrive in high altitude and plain habitats when faced with hypoxic conditions.
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Affiliation(s)
- Mengyang Li
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Xiangyu Tian
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Xiujuan Li
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Maolin Huang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Shuang Huang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Yue Wu
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Mengwan Jiang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Yuhua Shi
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Luye Shi
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China.
| | - Zhenlong Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China; School of Physical Education (Main campus), Zhengzhou University, Zhengzhou 450001, Henan, China.
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16
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Fang J, Wang H, Xue Z, Cheng Y, Zhang X. PPARγ: The Central Mucus Barrier Coordinator in Ulcerative Colitis. Inflamm Bowel Dis 2021; 27:732-741. [PMID: 33772551 DOI: 10.1093/ibd/izaa273] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Indexed: 12/16/2022]
Abstract
Ulcerative colitis (UC) is an idiopathic, long-term inflammatory disorder of the colon, characterized by a continuous remitting and relapsing course. The intestinal mucus barrier is the first line at the interface between the host and microbiota and acts to protect intestinal epithelial cells from invasion. Data from patients and animal studies have shown that an impaired mucus barrier is closely related to the severity of UC. Depletion of the mucus barrier is not just the strongest but is also the only independent risk factor predicting relapse in patients with UC. Peroxisome proliferator-activated receptor gamma (PPARγ), a nuclear transcription regulator, is involved in the regulation of inflammatory cytokine expression. It is also known to promote mucus secretion under pathological conditions to expel pathogenic bacteria or toxins. More important, PPARγ has been shown to affect host-microbiota interactions by modulating the energy metabolism of colonocytes and the oxygen availability of the intestinal microbiome. It is well known that gut microbiota homeostasis is essential for butyrate generation by the commensal bacteria to supply energy resources for colonocytes. Therefore, it can be speculated that PPARγ, as a central coordinator of the mucus barrier, may be a promising target for the development of effective agents to combat UC.
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Affiliation(s)
- Jian Fang
- Department of Preventive Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang Province, People's Republic of China.,College of Medicine, Shaoxing University, Shaoxing, Zhejiang Province, People's Republic of China
| | - Hui Wang
- Department of Colorectal Surgery, Shaoxing People's Hospital, Shaoxing, Zhejiang Province, People's Republic of China
| | - Zhe Xue
- Department of Preventive Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang Province, People's Republic of China
| | - Yinyin Cheng
- Department of Preventive Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang Province, People's Republic of China
| | - Xiaohong Zhang
- Department of Preventive Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang Province, People's Republic of China
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17
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Dengler F, Sova S, Salo AM, Mäki JM, Koivunen P, Myllyharju J. Expression and Roles of Individual HIF Prolyl 4-Hydroxylase Isoenzymes in the Regulation of the Hypoxia Response Pathway along the Murine Gastrointestinal Epithelium. Int J Mol Sci 2021; 22:4038. [PMID: 33919829 PMCID: PMC8070794 DOI: 10.3390/ijms22084038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/07/2021] [Accepted: 04/11/2021] [Indexed: 12/11/2022] Open
Abstract
The HIF prolyl 4-hydroxylases (HIF-P4H) control hypoxia-inducible factor (HIF), a powerful mechanism regulating cellular adaptation to decreased oxygenation. The gastrointestinal epithelium subsists in "physiological hypoxia" and should therefore have an especially well-designed control over this adaptation. Thus, we assessed the absolute mRNA expression levels of the HIF pathway components, Hif1a, HIF2a, Hif-p4h-1, 2 and 3 and factor inhibiting HIF (Fih1) in murine jejunum, caecum and colon epithelium using droplet digital PCR. We found a higher expression of all these genes towards the distal end of the gastrointestinal tract. We detected mRNA for Hif-p4h-1, 2 and 3 in all parts of the gastrointestinal tract. Hif-p4h-2 had significantly higher expression levels compared to Hif-p4h-1 and 3 in colon and caecum epithelium. To test the roles each HIF-P4H isoform plays in the gut epithelium, we measured the gene expression of classical HIF target genes in Hif-p4h-1-/-, Hif-p4h-2 hypomorph and Hif-p4h-3-/- mice. Only Hif-p4h-2 hypomorphism led to an upregulation of HIF target genes, confirming a predominant role of HIF-P4H-2. However, the abundance of Hif-p4h-1 and 3 expression in the gastrointestinal epithelium implies that these isoforms may have specific functions as well. Thus, the development of selective inhibitors might be useful for diverging therapeutic needs.
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Affiliation(s)
- Franziska Dengler
- Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine, 1210 Vienna, Austria
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
- Institute of Veterinary Physiology, University of Leipzig, 04103 Leipzig, Germany
| | - Sofia Sova
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
| | - Antti M. Salo
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
| | - Joni M. Mäki
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
| | - Peppi Koivunen
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
| | - Johanna Myllyharju
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, 90220 Oulu, Finland; (S.S.); (A.M.S.); (J.M.M.); (P.K.); (J.M.)
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18
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Butyrate Protects Porcine Colon Epithelium from Hypoxia-Induced Damage on a Functional Level. Nutrients 2021; 13:nu13020305. [PMID: 33498991 PMCID: PMC7911740 DOI: 10.3390/nu13020305] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/07/2021] [Accepted: 01/19/2021] [Indexed: 12/13/2022] Open
Abstract
The large intestinal epithelium is confronted with the necessity to adapt quickly to varying levels of oxygenation. In contrast to other tissues, it meets this requirement successfully and remains unharmed during (limited) hypoxic periods. The large intestine is also the site of bacterial fermentation producing short-chain fatty acids (SCFA). Amongst these SCFA, butyrate has been reported to ameliorate many pathological conditions. Thus, we hypothesized that butyrate protects the colonocytes from hypoxic damage. We used isolated porcine colon epithelium mounted in Ussing chambers, incubated it with or without butyrate and simulated hypoxia by changing the gassing regime to test this hypothesis. We found an increase in transepithelial conductance and a decrease in short-circuit current across the epithelia when simulating hypoxia for more than 30 min. Incubation with 50 mM butyrate significantly ameliorated these changes to the epithelial integrity. In order to characterize the protective mechanism, we compared the effects of butyrate to those of iso-butyrate and propionate. These two SCFAs exerted similar effects to butyrate. Therefore, we propose that the protective effect of butyrate on colon epithelium under hypoxia is not (only) based on its nutritive function, but rather on the intracellular signaling effects of SCFA.
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19
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Lee JS, Wang RX, Alexeev EE, Colgan SP. Intestinal Inflammation as a Dysbiosis of Energy Procurement: New Insights into an Old Topic. Gut Microbes 2021; 13:1-20. [PMID: 33583319 PMCID: PMC7889129 DOI: 10.1080/19490976.2021.1880241] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 01/04/2021] [Accepted: 01/11/2021] [Indexed: 02/07/2023] Open
Abstract
Inflammatory bowel disease (IBD) coincides with profound shifts in microbiota and host metabolic energy supply and demand. The gastrointestinal epithelium is anatomically positioned to provide a selective barrier between the anaerobic luminal microbiota and host lamina propria, with the microbiota and epithelium participating in an intricate energy exchange necessary for homeostasis. Maintenance and restoration of the barrier requires high energy flux and places significant demands on available substrates to generate ATP. It is recently appreciated that components of the microbiota contribute significantly to a multitude of biochemical pathways within and outside of the mucosa. Decades-old studies have appreciated that byproducts of the microbiota provide essential sources of energy to the intestinal epithelium, especially the colon. More recent work has unveiled the existence of numerous microbial-derived metabolites that support energy procurement within the mucosa. It is now appreciated that disease-associated shifts in the microbiota, termed dysbiosis, places significant demands on energy acquisition within the mucosa. Here, we review the topic of host- and microbial-derived components that influence tissue energetics in health and during disease.
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Affiliation(s)
- J. Scott Lee
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, United States
| | - Ruth X. Wang
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, United States
| | - Erica E. Alexeev
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, United States
- Department of Gastroenterology, Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, United States
| | - Sean P. Colgan
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, United States
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20
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Maltseva DV, Poloznikov AA, Artyushenko VG. Selective changes in expression of integrin α-subunits in the intestinal epithelial Caco-2 cells under conditions of hypoxia and microcirculation. BULLETIN OF RUSSIAN STATE MEDICAL UNIVERSITY 2020. [DOI: 10.24075/brsmu.2020.078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intestinal epithelial cells are constantly exposed to physiologically hypoxic environment. The further reduction of tissue oxygen delivery may result in the intestinal epithelial cells function impairment, being a sign of active inflammation. The cultivation conditions are important when performing in vitro studies, since those may affect the cells’ properties. The study was aimed to assess the integrin receptor expression in the human colon adenocarcinoma Caco-2 cell line when simulating both hypoxic condition using the cobalt chloride and microcirculation. Transcriptome analysis revealed the significantly increased expression of the integrin receptors ITGA2 and ITGA5 α2- and α5-subunit genes under hypoxic conditions, as well as the reduction of ITGA5 during incubation in the microfluidic chip. The expression of β-subunits did not change. Analysis of microRNA transcriptomes revealed the decreased expression of hsa-miR-766-3p and hsa-miR-23b-5p microRNA. One of the validated targets for both microRNAs is mRNA of gene ITGA5. It has been shown that microcirculation makes it possible to bring the intestinal epithelial cells cultivation conditions closer to physiological conditions. The possible biological significance of the detected integrin expression profile alterations and the role of microcirculation have been discussed.
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Affiliation(s)
- DV Maltseva
- National Research University Higher School of Economics, Moscow, Russia
| | - AA Poloznikov
- National Research University Higher School of Economics, Moscow, Russia
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21
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Dengler F. Activation of AMPK under Hypoxia: Many Roads Leading to Rome. Int J Mol Sci 2020; 21:ijms21072428. [PMID: 32244507 PMCID: PMC7177550 DOI: 10.3390/ijms21072428] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/26/2020] [Accepted: 03/30/2020] [Indexed: 12/13/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is known as a pivotal cellular energy sensor, mediating the adaptation to low energy levels by deactivating anabolic processes and activating catabolic processes in order to restore the cellular ATP supply when the cellular AMP/ATP ratio is increased. Besides this well-known role, it has also been shown to exert protective effects under hypoxia. While an insufficient supply with oxygen might easily deplete cellular energy levels, i.e., ATP concentration, manifold other mechanisms have been suggested and are heavily disputed regarding the activation of AMPK under hypoxia independently from cellular AMP concentrations. However, an activation of AMPK preceding energy depletion could induce a timely adaptation reaction preventing more serious damage. A connection between AMPK and the master regulator of hypoxic adaptation via gene transcription, hypoxia-inducible factor (HIF), has also been taken into account, orchestrating their concerted protective action. This review will summarize the current knowledge on mechanisms of AMPK activation under hypoxia and its interrelationship with HIF.
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Affiliation(s)
- Franziska Dengler
- Institute of Veterinary Physiology, University of Leipzig, D-04103 Leipzig, Germany
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22
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Zhang M, Chen H, Liu L, Xu L, Wang X, Chang L, Chang Q, Lu G, Jiang J, Zhu L. The Changes in the Frog Gut Microbiome and Its Putative Oxygen-Related Phenotypes Accompanying the Development of Gastrointestinal Complexity and Dietary Shift. Front Microbiol 2020; 11:162. [PMID: 32194513 PMCID: PMC7062639 DOI: 10.3389/fmicb.2020.00162] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 01/22/2020] [Indexed: 12/05/2022] Open
Abstract
There are many examples of symbiotic and reciprocal relationships in ecological systems; animal gut microbiome-host interactions are one such kind of bidirectional and complex relationship. Here, we utilized several approaches (16S rRNA gene sequencing, metagenomics, and transcriptomics) to explore potential gut microbiome-host interactions accompanying the development of gastrointestinal complexity and a dietary shift from metamorphosis to maturity in ornamented pygmy frogs (Microhyla fissipes). We identified the possible coevolution between a particular gut microbial group (increased putative fat-digesting Erysipelotrichaceae and chitin-digesting Bacteroides and Ruminococcaceae) and the host dietary shift [from herbivore to insectivore (high proportion of dietary chitin and fat)] during metamorphosis. We also found that the remodeling and complexity of the gastrointestinal system during metamorphosis might have a profound effect on the gut microbial community (decreasing facultative anaerobic Proteobacteria and increasing anaerobic Firmicutes) and its putative oxygen-related phenotypes. Moreover, a high proportion of chitin-digesting bacteria and increased carbohydrate metabolism by gut microbiomes at the climax of metamorphosis would help the frog's nutrition and energy needs during metamorphosis and development. Considering the increased expression of particular host genes (e.g., chitinase) in juvenile frogs, we speculate that host plays an important role in amphibian metamorphosis, and their symbiotic gut microbiome may help in this process by providing the nutrition and energy needs. We provide this basic information for the amphibian conservation and managements.
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Affiliation(s)
- Mengjie Zhang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Hua Chen
- Hangzhou Legenomics Bio-Pham Technology Co., Ltd., Hangzhou, China
| | - Lusha Liu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Liangliang Xu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Xungang Wang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Liming Chang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Qing Chang
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Guoqing Lu
- Department of Biology, University of Nebraska Omaha, Omaha, NE, United States
| | - Jianping Jiang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Lifeng Zhu
- School of Life Sciences, Nanjing Normal University, Nanjing, China
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23
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Vatnehol SAS, Hol PK, Bjørnerud A, Amiry-Moghaddam M, Haglerød C, Storås TH. Effect of Drinking Oxygenated Water Assessed by in vivo MRI Relaxometry. J Magn Reson Imaging 2020; 52:720-728. [PMID: 32100358 DOI: 10.1002/jmri.27104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/12/2020] [Accepted: 02/12/2020] [Indexed: 01/07/2023] Open
Abstract
GRANT SUPPORT This project was funded by the Research Council of Norway. BACKGROUND Oxygen uptake through the gastrointestinal tract after oral administration of oxygenated water in humans is not well studied and is debated in the literature. Due to the paramagnetic properties of oxygen and deoxyhemoglobin, MRI as a technique might be able to detect changes in relaxometry values caused by increased oxygen levels in the blood. PURPOSE To assess whether oxygen dissolved in water is absorbed from the gastrointestinal tract and transported into the bloodstream after oral administration. STUDY TYPE A randomized, double-blinded, placebo-controlled crossover trial. POPULATION/SUBJECTS Thirty healthy male volunteers age 20-35. FIELD STRENGTH/SEQUENCE 3T/Modified Look-Locker inversion recovery (MOLLI) T1 -mapping and multi fast field echo (mFFE) T2 *-mapping. ASSESSMENT Each volunteer was scanned in two separate sessions. T1 and T2 * maps were acquired repeatedly covering the hepatic portal vein (HPV) and vena cava inferior (VCI, control vein) before and after intake of oxygenated or control water. Assessments were done by placing a region of interest in the HPV and VCI. STATISTICAL TEST A mixed linear model was performed to the compare control vs. oxygen group. RESULTS Drinking caused a mean 1.6% 95% CI (1.1-2.0% P < 0.001) increase in T1 of HPV blood and water oxygenation attributed another 0.70% 95% confidence interval (CI) (0.07-1.3% P = 0.028) increase. Oxygenation did not change T1 in VCI blood. Mean T2 * increased 9.6% 95% CI (1.7-17.5% P = 0.017) after ingestion of oxygenated water and 1.2% 95% CI (-4.3-6.8% P = 0.661) after ingestion of control water. The corresponding changes in VCI blood were not significant. DATA CONCLUSION Ingestion of water caused changes in T1 and T2 * of HPV blood compatible with dilution due to water absorption. The effects were enhanced by oxygen. Assessment of oxygen enrichment of HPV blood was not possible due to the dilution effect. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:720-728.
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Affiliation(s)
- Svein Are Sirirud Vatnehol
- Faculty of Medicine, University of Oslo, Oslo, Norway.,The Intervention Centre, Oslo University Hospital, Oslo, Norway.,Oxy Solutions AS, Oslo, Norway
| | - Per Kristian Hol
- Faculty of Medicine, University of Oslo, Oslo, Norway.,The Intervention Centre, Oslo University Hospital, Oslo, Norway
| | - Atle Bjørnerud
- Department of Physics, University of Oslo, Oslo, Norway.,Division of Radiology and Nuclear Medicine, Computational Radiology and Artificial Intelligence, Oslo University Hospital, Oslo, Norway
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24
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Chen Y, Koike Y, Chi L, Ahmed A, Miyake H, Li B, Lee C, Delgado-Olguín P, Pierro A. Formula feeding and immature gut microcirculation promote intestinal hypoxia, leading to necrotizing enterocolitis. Dis Model Mech 2019; 12:dmm.040998. [PMID: 31704804 PMCID: PMC6918740 DOI: 10.1242/dmm.040998] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 10/28/2019] [Indexed: 01/09/2023] Open
Abstract
Major risk factors for necrotizing enterocolitis (NEC) are formula feeding and prematurity; however, their pathogenic mechanisms are unknown. Here, we found that insufficient arginine/nitric oxide synthesis limits blood flow in the intestinal microvasculature, leading to hypoxia, mucosal damage and NEC in the premature intestine after formula feeding. Formula feeding led to increased intestinal hypoxia in pups at postnatal day (P)1 and P5, but not in more mature pups at P9. Accordingly, blood flow in the intestinal microvasculature increased after formula feeding in P9 pups only. mRNA profiling revealed that regulators of arginine/nitric oxide synthesis are at higher levels in endothelial cells of the intestine in P9 than in P1 pups. Importantly, arginine supplementation increased intestinal microvasculature blood flow and prevented NEC, whereas an arginine antagonist exacerbated NEC. Our results suggest that balancing intestinal oxygen demand and supply in the premature intestine by modulating arginine/nitric oxide could be used to prevent NEC.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Yong Chen
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada.,Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON M5G1X8, Canada.,Department of Pediatric Surgery, KK Women's and Children's Hospital, 100 Bukit Timah Road, 229899 Singapore
| | - Yuhki Koike
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada.,Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON M5G1X8, Canada
| | - Lijun Chi
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S1A8, Canada
| | - Abdalla Ahmed
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S1A8, Canada
| | - Hiromu Miyake
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada.,Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON M5G1X8, Canada
| | - Bo Li
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada
| | - Carol Lee
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada
| | - Paul Delgado-Olguín
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada .,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S1A8, Canada.,Heart and Stroke Richard Lewar Centre of Excellence in Cardiovascular Research, Toronto, ON M5S3H2, Canada
| | - Agostino Pierro
- Translational Medicine, The Hospital for Sick Children, Toronto, ON M5G0A4, Canada .,Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON M5G1X8, Canada
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25
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De Gregorio V, Corrado B, Sbrescia S, Sibilio S, Urciuolo F, Netti PA, Imparato G. Intestine-on-chip device increases ECM remodeling inducing faster epithelial cell differentiation. Biotechnol Bioeng 2019; 117:556-566. [PMID: 31598957 DOI: 10.1002/bit.27186] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 09/11/2019] [Accepted: 10/01/2019] [Indexed: 12/13/2022]
Abstract
An intestine-on-chip has been developed to study intestinal physiology and pathophysiology as well as intestinal transport absorption and toxicity studies in a controlled and human similar environment. Here, we report that dynamic culture of an intestine-on-chip enhances extracellular matrix (ECM) remodeling of the stroma, basement membrane production and speeds up epithelial differentiation. We developed a three-dimensional human intestinal stromal equivalent composed of human intestinal subepithelial myofibroblasts embedded in their own ECM. Then, we cultured human colon carcinoma-derived cells in both static and dynamic conditions in the opportunely designed microfluidic system until the formation of a well-oriented epithelium. This low cost and handy microfluidic device allows to qualitatively and quantitatively detect epithelial polarization and mucus production as well as monitor barrier function and ECM remodeling after nutraceutical treatment.
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Affiliation(s)
- Vincenza De Gregorio
- Center for Advanced Biomaterials for HealthCare@CRIB, Istituto Italiano di Tecnologia, Naples, Italy
| | - Brunella Corrado
- Departments of Naples, National Research Council, Institute for Microelectronics and Microsystems, Naples, Italy
| | | | - Sara Sibilio
- Department of Chemical Materials and Industrial Production (DICMAPI), University of Naples Federico II, Naples, Italy
| | - Francesco Urciuolo
- Department of Chemical Materials and Industrial Production (DICMAPI), University of Naples Federico II, Naples, Italy.,Interdisciplinary Research Centre on Biomaterials (CRIB), University of Naples Federico II, Naples, Italy
| | - Paolo A Netti
- Center for Advanced Biomaterials for HealthCare@CRIB, Istituto Italiano di Tecnologia, Naples, Italy.,Department of Chemical Materials and Industrial Production (DICMAPI), University of Naples Federico II, Naples, Italy.,Interdisciplinary Research Centre on Biomaterials (CRIB), University of Naples Federico II, Naples, Italy
| | - Giorgia Imparato
- Center for Advanced Biomaterials for HealthCare@CRIB, Istituto Italiano di Tecnologia, Naples, Italy
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Kim R, Attayek PJ, Wang Y, Furtado KL, Tamayo R, Sims CE, Allbritton NL. An in vitro intestinal platform with a self-sustaining oxygen gradient to study the human gut/microbiome interface. Biofabrication 2019; 12:015006. [PMID: 31519008 DOI: 10.1088/1758-5090/ab446e] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An oxygen gradient formed along the length of colonic crypts supports stem-cell proliferation at the normoxic crypt base while supporting obligate anaerobe growth in the anoxic colonic lumen. Primary human colonic epithelial cells derived from human gastrointestinal stem cells were cultured within a device possessing materials of tailored oxygen permeability to produce an oxygen-depleted luminal (0.8% ± 0.1% O2) and oxygen-rich basal (11.1% ± 0.5% O2) compartment. This oxygen difference created a stable oxygen gradient across the colonic epithelial cells which remained viable and properly polarized. Facultative and obligate anaerobes Lactobacillus rhamnosus, Bifidobacterium adolescentis, and Clostridium difficile grew readily within the luminal compartment. When formed along the length of an in vitro crypt, the oxygen gradient facilitated cell compartmentalization within the crypt by enhancing confinement of the proliferative cells to the crypt base. This platform provides a simple system to create a physiological oxygen gradient across an intestinal mimic while simultaneously supporting anaerobe co-culture.
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Affiliation(s)
- Raehyun Kim
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, and North Carolina State University, Raleigh, NC, United States of America
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Dengler F, Gäbel G. The Fast Lane of Hypoxic Adaptation: Glucose Transport Is Modulated via A HIF-Hydroxylase-AMPK-Axis in Jejunum Epithelium. Int J Mol Sci 2019; 20:ijms20204993. [PMID: 31601024 PMCID: PMC6834319 DOI: 10.3390/ijms20204993] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/07/2019] [Accepted: 10/08/2019] [Indexed: 12/21/2022] Open
Abstract
The intestinal epithelium is able to adapt to varying blood flow and, thus, oxygen availability. Still, the adaptation fails under pathologic situations. A better understanding of the mechanisms underlying the epithelial adaptation to hypoxia could help to improve the therapeutic approach. We hypothesized that the short-term adaptation to hypoxia is mediated via AMP-activated protein kinase (AMPK) and that it is coupled to the long-term adaptation by a common regulation mechanism, the HIF-hydroxylase enzymes. Further, we hypothesized the transepithelial transport of glucose to be part of this short-term adaptation. We conducted Ussing chamber studies using isolated lagomorph jejunum epithelium and cell culture experiments with CaCo-2 cells. The epithelia and cells were incubated under 100% and 21% O2, respectively, with the panhydroxylase inhibitor dimethyloxalylglycine (DMOG) or under 1% O2. We showed an activation of AMPK under hypoxia and after incubation with DMOG by Western blot. This could be related to functional effects like an impairment of Na+-coupled glucose transport. Inhibitor studies revealed a recruitment of glucose transporter 1 under hypoxia, but not after incubation with DMOG. Summing up, we showed an influence of hydroxylase enzymes on AMPK activity and similarities between hypoxia and the effects of hydroxylase inhibition on functional changes.
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Affiliation(s)
- Franziska Dengler
- Institute of Veterinary Physiology, University of Leipzig, 04103 Leipzig, Germany.
| | - Gotthold Gäbel
- Institute of Veterinary Physiology, University of Leipzig, 04103 Leipzig, Germany.
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28
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Coping With Hypoxia: Adaptation of Glucose Transport Mechanisms Across Equine Jejunum Epithelium. J Equine Vet Sci 2018. [DOI: 10.1016/j.jevs.2018.05.221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Inflammatory bowel diseases broadly categorized into Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gastrointestinal tract with increasing prevalence worldwide. The etiology of the disease is complex and involves a combination of genetic, environmental, immunological and gut microbial factors. Recurring and bloody diarrhea is the most prevalent and debilitating symptom in IBD. The pathogenesis of IBD-associated diarrhea is multifactorial and is essentially an outcome of mucosal damage caused by persistent inflammation resulting in dysregulated intestinal ion transport, impaired epithelial barrier function and increased accessibility of the pathogens to the intestinal mucosa. Altered expression and/or function of epithelial ion transporters and channels is the principle cause of electrolyte retention and water accumulation in the intestinal lumen leading to diarrhea in IBD. Aberrant barrier function further contributes to diarrhea via leak-flux mechanism. Mucosal penetration of enteric pathogens promotes dysbiosis and exacerbates the underlying immune system further perpetuating IBD associated-tissue damage and diarrhea. Here, we review the mechanisms of impaired ion transport and loss of epithelial barrier function contributing to diarrhea associated with IBD.
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Affiliation(s)
- Arivarasu N Anbazhagan
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA
| | - Shubha Priyamvada
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA
| | - Waddah A Alrefai
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA.,b Jesse Brown VA Medical Center , Chicago , IL , USA
| | - Pradeep K Dudeja
- a Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago , IL , USA.,b Jesse Brown VA Medical Center , Chicago , IL , USA
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Dengler F, Rackwitz R, Pfannkuche H, Gäbel G. Glucose transport across lagomorph jejunum epithelium is modulated by AMP-activated protein kinase under hypoxia. J Appl Physiol (1985) 2017; 123:1487-1500. [PMID: 28860168 DOI: 10.1152/japplphysiol.00436.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The gastrointestinal epithelium possesses adaptation mechanisms to cope with huge variations in blood flow and subsequently oxygenation. Since sufficient energy supply is crucial under hypoxic conditions, glucose uptake especially must be regulated by these adaptation mechanisms. Therefore, we investigated glucose transport under hypoxic conditions. Jejunal epithelia of rabbits were incubated in Ussing chambers under short-circuit current conditions. Hypoxia was simulated by gassing with 1% O2 instead of 100% O2. The activity of sodium-coupled glucose transporter-1 (SGLT-1) was assessed by measuring the increase of short circuit current ( Isc) after the addition of 2 mM glucose to the mucosal buffer solution. We observed decreased activity of SGLT-1 after hypoxia compared with control conditions. To investigate underlying mechanisms, epithelia were exposed to agonists and antagonists of AMP-activated protein kinase (AMPK) before assessment of SGLT-1-mediated transport and the pAMPK/AMPK protein ratio. Preincubation with the antagonist restored SGLT-1 activity under hypoxic conditions to the level of control conditions, indicating an involvement of AMPK in the downregulation of SGLT-1 activity under hypoxia, which was confirmed in Western blot analysis of pAMPK/AMPK. Transepithelial flux studies using radioactively labeled glucose, ortho-methyl-glucose, fructose, and mannitol revealed no changes after hypoxic incubation. Therefore, we could exclude a decreased transepithelial glucose transport rate and increased paracellular conductance under hypoxia. In conclusion, our study hints at a decreased activity of SGLT-1 under hypoxic conditions in an AMPK-dependent manner. However, transepithelial transport of glucose is maintained. Therefore, we suggest other transport mechanisms, especially glucose transporter 1 and/or 2 to substitute SGLT-1 under hypoxia. NEW & NOTEWORTHY To our knowledge, this is the first approach to simulate hypoxia and study its effects in the jejunal epithelium using the Ussing chamber technique. We were able show that AMPK plays a role in the downregulation of SGLT-1 and that there seems to be an upregulation of other glucose transport mechanisms in the apical membrane of lagomorph jejunum epithelium under hypoxia, securing the epithelial energy supply and thus integrity.
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Affiliation(s)
| | - Reiko Rackwitz
- Institute of Veterinary Physiology, University of Leipzig , Germany
| | - Helga Pfannkuche
- Institute of Veterinary Physiology, University of Leipzig , Germany
| | - Gotthold Gäbel
- Institute of Veterinary Physiology, University of Leipzig , Germany
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31
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AlKukhun A, Caturegli G, Munoz-Abraham AS, Judeeba S, Patron-Lozano R, Morotti R, Rodriguez-Davalos MI, Geibel JP. Use of Fluorescein Isothiocyanate-Inulin as a Marker for Intestinal Ischemic Injury. J Am Coll Surg 2017; 224:1066-1073. [DOI: 10.1016/j.jamcollsurg.2016.12.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 10/09/2016] [Accepted: 12/05/2016] [Indexed: 12/14/2022]
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32
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Šket R, Treichel N, Debevec T, Eiken O, Mekjavic I, Schloter M, Vital M, Chandler J, Tiedje JM, Murovec B, Prevoršek Z, Stres B. Hypoxia and Inactivity Related Physiological Changes (Constipation, Inflammation) Are Not Reflected at the Level of Gut Metabolites and Butyrate Producing Microbial Community: The PlanHab Study. Front Physiol 2017; 8:250. [PMID: 28522975 PMCID: PMC5416748 DOI: 10.3389/fphys.2017.00250] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 04/10/2017] [Indexed: 12/12/2022] Open
Abstract
We explored the assembly of intestinal microbiota in healthy male participants during the run-in (5 day) and experimental phases [21-day normoxic bed rest (NBR), hypoxic bedrest (HBR)], and hypoxic ambulation (HAmb) in a strictly controlled laboratory environment, balanced fluid, and dietary intakes, controlled circadian rhythm, microbial ambiental burden, and 24/7 medical surveillance. The fraction of inspired O2 (FiO2) and partial pressure of inspired O2 (PiO2) were 0.209 and 133.1 ± 0.3 mmHg for NBR and 0.141 ± 0.004 and 90.0 ± 0.4 mmHg for both hypoxic variants (HBR and HAmb; ~4,000 m simulated altitude), respectively. A number of parameters linked to intestinal transit spanning Bristol Stool Scale, defecation rates, zonulin, α1-antitrypsin, eosinophil derived neurotoxin, bile acids, reducing sugars, short chain fatty acids, total soluble organic carbon, water content, diet composition, and food intake were measured (167 variables). The abundance, structure, and diversity of butyrate producing microbial community were assessed using the two primary bacterial butyrate synthesis pathways, butyryl-CoA: acetate CoA-transferase (but) and butyrate kinase (buk) genes. Inactivity negatively affected fecal consistency and in combination with hypoxia aggravated the state of gut inflammation (p < 0.05). In contrast, gut permeability, various metabolic markers, the structure, diversity, and abundance of butyrate producing microbial community were not significantly affected. Rearrangements in the butyrate producing microbial community structure were explained by experimental setup (13.4%), experimentally structured metabolites (12.8%), and gut metabolite-immunological markers (11.9%), with 61.9% remaining unexplained. Many of the measured parameters were found to be correlated and were hence omitted from further analyses. The observed progressive increase in two immunological intestinal markers suggested that the transition from healthy physiological state toward the developed symptoms of low magnitude obesity-related syndromes was primarily driven by the onset of inactivity (lack of exercise in NBR) that were exacerbated by systemic hypoxia (HBR) and significantly alleviated by exercise, despite hypoxia (HAmb). Butyrate producing community in colon exhibited apparent resilience toward short-term modifications in host exercise or hypoxia. Progressive constipation (decreased intestinal motility) and increased local inflammation marker suggest that changes in microbial colonization and metabolism were taking place at the location of small intestine.
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Affiliation(s)
- Robert Šket
- Department of Animal Science, Biotechnical Faculty, University of LjubljanaLjubljana, Slovenia
| | - Nicole Treichel
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München - German Research Center for Environmental HealthNeuherberg, Germany
| | - Tadej Debevec
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan InstituteLjubljana, Slovenia
| | - Ola Eiken
- Department of Environmental Physiology, Swedish Aerospace Physiology Centre, Royal Institute of TechnologyStockholm, Sweden
| | - Igor Mekjavic
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan InstituteLjubljana, Slovenia
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München - German Research Center for Environmental HealthNeuherberg, Germany
| | - Marius Vital
- Center for Microbial Ecology, Michigan State UniversityEast Lansing, MI, USA
| | - Jenna Chandler
- Center for Microbial Ecology, Michigan State UniversityEast Lansing, MI, USA
| | - James M Tiedje
- Center for Microbial Ecology, Michigan State UniversityEast Lansing, MI, USA
| | - Boštjan Murovec
- Laboratory for Artificial Sight and Automation, Faculty of Electrical Sciences, University of LjubljanaLjubljana, Slovenia
| | - Zala Prevoršek
- Department of Animal Science, Biotechnical Faculty, University of LjubljanaLjubljana, Slovenia
| | - Blaž Stres
- Department of Animal Science, Biotechnical Faculty, University of LjubljanaLjubljana, Slovenia.,Center for Clinical Neurophysiology, Faculty of Medicine, University of LjubljanaLjubljana, Slovenia
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Changes in the Luminal Environment of the Colonic Epithelial Cells and Physiopathological Consequences. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:476-486. [PMID: 28082121 DOI: 10.1016/j.ajpath.2016.11.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 11/21/2016] [Accepted: 11/23/2016] [Indexed: 12/28/2022]
Abstract
Evidence, mostly from experimental models, has accumulated, indicating that modifications of bacterial metabolite concentrations in the large intestine luminal content, notably after changes in the dietary composition, may have important beneficial or deleterious consequences for the colonic epithelial cell metabolism and physiology in terms of mitochondrial energy metabolism, reactive oxygen species production, gene expression, DNA integrity, proliferation, and viability. Recent data suggest that for some bacterial metabolites, like hydrogen sulfide and butyrate, the extent of their oxidation in colonocytes affects their capacity to modulate gene expression in these cells. Modifications of the luminal bacterial metabolite concentrations may, in addition, affect the colonic pH and osmolarity, which are known to affect colonocyte biology per se. Although the colonic epithelium appears able to face, up to some extent, changes in its luminal environment, notably by developing a metabolic adaptive response, some of these modifications may likely affect the homeostatic process of colonic epithelium renewal and the epithelial barrier function. The contribution of major changes in the colonocyte luminal environment in pathological processes, like mucosal inflammation, preneoplasia, and neoplasia, although suggested by several studies, remains to be precisely evaluated, particularly in a long-term perspective.
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34
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Shulhan J, Dicken B, Hartling L, Larsen BM. Current Knowledge of Necrotizing Enterocolitis in Preterm Infants and the Impact of Different Types of Enteral Nutrition Products. Adv Nutr 2017; 8:80-91. [PMID: 28096129 PMCID: PMC5227976 DOI: 10.3945/an.116.013193] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Preterm infants are extremely vulnerable to a range of morbidities and mortality. Underdeveloped cardiac, respiratory, gastrointestinal, and immune systems in the preterm period increase the risk of necrotizing enterocolitis (NEC), a serious disease of the gut. NEC affects 5-12% of very-low birth-weight infants, leads to surgery in 20-40% of cases, and is fatal in 25-50% of cases. There are multiple factors that may contribute to NEC, but the exact cause is not yet fully understood. Severe cases can result in intestinal resection or death, and the health care costs average >$300,000/infant when surgical management is required. Different types of nutrition may affect the onset or progression of NEC. Several studies have indicated that bovine milk-based infant formulas lead to a higher incidence of NEC in preterm infants than does human milk (HM). However, it is not clear why HM is linked to a lower incidence of NEC or why some infants fed an exclusively HM diet still develop NEC. An area that has not been thoroughly explored is the use of semielemental or elemental formulas. These specialty formulas are easy to digest and absorb in the gut and may be an effective nutritional intervention for reducing the risk of NEC. This review summarizes what is known about the factors that contribute to the onset and progression of NEC, discusses its health care cost implications, and explores the impact that different formulas and HM have on this disease.
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Affiliation(s)
- Jocelyn Shulhan
- Departments of Pediatrics and
- Alberta Research Centre for Health Evidence, University of Alberta, Edmonton, Canada
| | - Bryan Dicken
- Surgery, Faculty of Medicine and Dentistry, and
- Stollery Children's Hospital, Edmonton, Canada; and
| | - Lisa Hartling
- Departments of Pediatrics and
- Alberta Research Centre for Health Evidence, University of Alberta, Edmonton, Canada
| | - Bodil Mk Larsen
- Departments of Pediatrics and
- Stollery Children's Hospital, Edmonton, Canada; and
- Nutrition Services, Alberta Health Services, Edmonton, Canada
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35
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Chen Y, Koike Y, Miyake H, Li B, Lee C, Hock A, Zani A, Pierro A. Formula feeding and systemic hypoxia synergistically induce intestinal hypoxia in experimental necrotizing enterocolitis. Pediatr Surg Int 2016; 32:1115-1119. [PMID: 27815640 DOI: 10.1007/s00383-016-3997-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/13/2016] [Indexed: 01/23/2023]
Abstract
PURPOSE Feeding and systemic hypoxia are major stresses inducing necrotizing enterocolitis (NEC). This study aims to investigate the role of systemic hypoxia in NEC and its effect before and after feeding. METHODS Neonatal mice were studied in three groups. Control (N = 9): breast feeding; NEC A (N = 8), gavage feeding + lipopolysaccharide (LPS) + preprandial hypoxia; and NEC B (N = 9), feeding + LPS + postprandial hypoxia. Pimonidazole, a hypoxia marker, was injected intraperitoneally before ileum was harvested for histology and quantitative RT-PCR studies. Statistical analysis was done using the ANOVA and Chi-square test. RESULTS NEC incidence was 62.5% in NEC A and 88.9% in NEC B. The mortality in NEC B (55.6%) but not A (25%) is significantly higher than control (0%, p < 0.05). Pimonidazole staining elevated in both NEC A and B with higher pimonidazole grade in NEC B (p < 0.01). Both NEC groups had increased the expression of hypoxia-related genes: HIF-1α, GLUT-1, and PHD-3 with GLUT-1 expressed more in NEC B compared with NEC A (p < 0.01). The inflammation marker, IL6, was similarly raised in both NEC A and B. CONCLUSION Feeding and postprandial hypoxia synergistically induce intestinal hypoxia in NEC. As feeding increases intestinal oxygen demand, maintaining a balance between intestinal oxygen supply and demand is important to prevent NEC.
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Affiliation(s)
- Y Chen
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada.,Department of Pediatric Surgery, KK Women's and Children's Hospital, Singapore, Singapore
| | - Y Koike
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada
| | - H Miyake
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada
| | - B Li
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada
| | - C Lee
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada
| | - A Hock
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada
| | - A Zani
- Division of General and Thoracic Surgery, Programme of Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Canada
| | - A Pierro
- Division of General and Thoracic Surgery, Programme of Physiology and Experimental Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada.
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36
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Liang X, Yin G, Ma Y, Xu K, Liu J, Li J. The critical role of mast cell-derived hypoxia-inducible factor-1α in regulating mast cell function. ACTA ACUST UNITED AC 2016; 68:1409-1416. [PMID: 27671226 DOI: 10.1111/jphp.12622] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 07/26/2016] [Indexed: 02/06/2023]
Abstract
OBJECTIVES During colorectal tumour progression, the tumour microenvironment becomes hypoxic, and infiltration of a large number of inflammatory cells occurs. The mast cells (MCs) are a type of immune cells plays an important role in tumour angiogenesis. However, it is unclear whether the role of MC in colorectal cancer is to promote or to inhibit tumour growth. METHODS Immunohistochemical analysis of clinical colorectal cancer samples and a colorectal carcinoma model were used. KEY FINDINGS We found the carcinomas and the adjacent tissues were infiltrated with large numbers of mast cells, and the MC infiltration quantity increased with the Dukes' stage. After tumour inoculation, the survival time of MC-deficient mice was remarkably longer than wild-type C57BL/6 mice, and the tumour growth rate of MC-deficient mice was slower than wild type. In addition, the survival time and tumour growth rate can be recovered in MC reconstruction mice. Furthermore, inhibition of the expression of hypoxia-inducible factor-1α (HIF-1α) using siRNA reduced the release of inflammatory factors and the degree of MC degranulation. CONCLUSIONS Mast cells promote the development of colorectal cancer, and MC-derived HIF-1α plays an important role in regulating MC function. Our study reveals a novel role of MC-derived HIF-1α in the colorectal carcinoma microenvironment.
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Affiliation(s)
- Xin Liang
- Department of General Surgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Guifang Yin
- State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Yuanyuan Ma
- Department of General Surgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Ke Xu
- Central Laboratory, Putuo Hospital and Interventional Cancer Institute of Chinese Integrative Medicine, Shanghai University of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Jianwen Liu
- State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China.
| | - Jiyu Li
- Department of General Surgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.
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37
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Schindele S, Pouokam E, Diener M. Hypoxia/Reoxygenation Effects on Ion Transport across Rat Colonic Epithelium. Front Physiol 2016; 7:247. [PMID: 27445839 PMCID: PMC4914783 DOI: 10.3389/fphys.2016.00247] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/03/2016] [Indexed: 12/04/2022] Open
Abstract
Ischemia causes severe damage in the gastrointestinal tract. Therefore, it is interesting to study how the barrier and transport functions of intestinal epithelium change under hypoxia and subsequent reoxygenation. For this purpose we simulated hypoxia and reoxygenation on mucosa-submucosa preparations from rat distal colon in Ussing chambers and on isolated crypts. Hypoxia (N2 gassing for 15 min) induced a triphasic change in short-circuit current (Isc): a transient decrease, an increase and finally a long-lasting fall below the initial baseline. During the subsequent reoxygenation phase, Isc slightly rose to values above the initial baseline. Tissue conductance (Gt) showed a biphasic increase during both the hypoxia and the reoxygenation phases. Omission of Cl− or preincubation of the tissue with transport inhibitors revealed that the observed changes in Isc represented changes in Cl− secretion. The radical scavenger trolox C reduced the Isc response during hypoxia, but failed to prevent the rise of Isc during reoxygenation. All changes in Isc were Ca2+-dependent. Fura-2 experiments at loaded isolated colonic crypts revealed a slow increase of the cytosolic Ca2+ concentration during hypoxia and the reoxygenation phase, mainly caused by an influx of extracellular Ca2+. Surprisingly, no changes could be detected in the fluorescence of the superoxide anion-sensitive dye mitosox or the thiol-sensitive dye thiol tracker, suggesting a relative high capacity of the colonic epithelium (with its low O2 partial pressure even under physiological conditions) to deal with enhanced radical production during hypoxia/reoxygenation.
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Affiliation(s)
- Sabine Schindele
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
| | - Ervice Pouokam
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
| | - Martin Diener
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
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Munoz-Abraham AS, Judeeba S, Alkukhun A, Alfadda T, Patron-Lozano R, Rodriguez-Davalos MI, Geibel JP. A new method to measure intestinal secretion using fluorescein isothiocyanate-inulin in small bowel of rats. J Surg Res 2015; 197:225-30. [PMID: 25976849 DOI: 10.1016/j.jss.2015.02.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/11/2015] [Accepted: 02/19/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND Small intestine ischemia can be seen in various conditions such as intestinal transplantation. To further understand the pathologic disruption in ischemia-reperfusion injury, we have developed a method to measure fluid changes in the intestinal lumen of rats. METHODS Two 10-cm rat intestine segments were procured, connected to the terminal apertures of a perfusion device, and continuously infused with 3 mL of HEPES solution (control solution) containing 50 μM of fluorescein isothiocyanate (FITC)-inulin. The perfusion device consists of concentric chambers that contain the perfused bowel segments, which are maintained at 37°C via H₂O bath. The individual chamber has four apertures as follows: two fill and/or drain the surrounding HEPES solution on the blood side of the tissue. The others provide flow of HEPES solution containing FITC-inulin through the lumens. The experimental intestine was infused with the same solution with 100 μM of Forskolin. A pump continuously circulated solutions at 6 mL/min. Samples were collected at 15-min intervals until 150 min and were measured by the nanoflourospectrometer. RESULTS A mean of 6-μM decrease in the FITC-inulin concentration in the Forskolin-treated experimental intestine was observed in comparison with that in the control intestine. The FITC-inulin count dilution in the experimental intestine is a result of an increase of fluid secretion produced by the effect of Forskolin, with P values <0.0001. CONCLUSIONS We demonstrate that it is possible to measure luminal fluid changes over time using our new modified perfusion system along with FITC-inulin to allow real-time determinations of fluid and/or electrolyte movement along the small intestine.
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Affiliation(s)
| | - Sami Judeeba
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Abedalrazaq Alkukhun
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Tariq Alfadda
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Roger Patron-Lozano
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | | | - John P Geibel
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut.
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