1
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Fang H, Wang X, Wang Z, Ma X, Zhang L, Yang L. Modulation of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum during early pregnancy. Domest Anim Endocrinol 2024; 89:106870. [PMID: 38954983 DOI: 10.1016/j.domaniend.2024.106870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Revised: 06/22/2024] [Accepted: 06/26/2024] [Indexed: 07/04/2024]
Abstract
The liver and intestine play a critical role in nutrient absorption, storage, and metabolism. The aim of this study was to evaluate expression pattern of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of the rapamycin (mTOR) signaling pathway that included PI3K, AKT1, mTOR, FoxO1, SREBP-1, PPARα, PTEN and FXR in the maternal liver and duodenum. Ovine livers and duodenums were sampled at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation, and RT-qPCR, western blot and immunohistochemistry analysis were used to detect mRNA and protein expression. The results showed that expression of PI3K, AKT1, p-mTOR, FoxO1, SREBP-1 and PTEN upregulated in the maternal liver, and PPARα upregulated in the duodenum. However, expression of FoxO1, SREBP-1 and PTEN in the duodenum downregulated during early pregnancy. In addition, expression levels of SREBP-1, PTEN and PPARα in the maternal liver, and PI3K in the duodenum peaked at day 13 of pregnancy. In addition, expression levels of PI3K, p-mTOR and FoxO1 in the liver, and AKT1 and p-mTOR in the duodenum peaked at day 16 of pregnancy. Nevertheless, expression levels of FXR both in the maternal liver duodenum downregulated at days 13 and 16 of pregnancy. In conclusion, early pregnancy regulated expression pattern of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum in a pregnancy stage-specific and tissue-specific manner, which may be necessary for the adaptations in maternal hepatic nutrient metabolism and intestinal nutrient absorption early pregnancy.
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Affiliation(s)
- Hongxu Fang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China
| | - Xinxin Wang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China
| | - Zhongyue Wang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China
| | - Xiaoxin Ma
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China
| | - Leying Zhang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China
| | - Ling Yang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, No. 19 Taiji Road, Handan 056038, PR China.
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2
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Fang YX, Lu EQ, Xu E, Zhang YY, Zhu M. Arf1 promotes porcine intestinal epithelial cell proliferation via the mTORC1 signaling pathway. In Vitro Cell Dev Biol Anim 2024:10.1007/s11626-024-00942-y. [PMID: 39093368 DOI: 10.1007/s11626-024-00942-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 06/20/2024] [Indexed: 08/04/2024]
Abstract
The promotion of gut health, a pervasive problem in modern animal husbandry, positively affects organismal health, productivity, and economics. Porcine intestinal epithelial cells (IPEC-J2) continuously proliferate to maintain intestinal homeostasis, including barrier, immune, and absorptive functions. Gut homeostasis is fundamental to organismal health. ADP-ribosylation factor 1 (Arf1), a small GTPase, plays a crucial role in coordinating mTORC1 in response to nutrients, especially amino acid availability in the gut. mTORC1 is the central hub of proliferation. Thus, it seems likely that Arf1 promotes IPEC-J2 cell proliferation. However, the exact role of Arf1 in the porcine gut remains unclear. Therefore, we evaluated the functional role and possible mechanisms of Arf1 in the porcine intestine through Arf1 overexpression and knockdown in IPEC-J2 cells. Arf1 overexpression and knockdown significantly enhanced and inhibited, respectively, IPEC-J2 cell viability, and PCNA expression varied with Arf1 expression. Moreover, the proportion of Ki67-positive cells was significantly greater in the Arf1-overexpressing group than in the control group. These results suggest that Arf1 improves IPEC-J2 cell proliferation. The underlying mechanism was explored by Western blotting. Arf1 overexpression and knockdown significantly enhanced and suppressed, respectively, the levels of p-S6K1 and p-RPS6, which are key downstream targets of the mTORC1 signaling pathway. Collectively, our findings reveal the role of the Arf1-mTORC1 axis in IPEC-J2 cell proliferation and its potential function in regulating intestinal homeostasis and health.
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Affiliation(s)
- Yong-Xia Fang
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - En-Qing Lu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - E Xu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - Yi-Yu Zhang
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China
| | - Min Zhu
- Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang, 550025, Guizhou Province, China.
- Institute of Animal Nutrition and Feed Science, Guizhou University, Guiyang, 550025, China.
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3
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Zhu H, Jia Z, Li YR, Danelisen I. Molecular mechanisms of action of metformin: latest advances and therapeutic implications. Clin Exp Med 2023; 23:2941-2951. [PMID: 37016064 PMCID: PMC10072049 DOI: 10.1007/s10238-023-01051-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 03/17/2023] [Indexed: 04/06/2023]
Abstract
Metformin is among the most widely used antidiabetic drugs. Studies over the past few years have identified multiple novel molecular targets and pathways that metformin acts on to exert its beneficial effects in treating type 2 diabetes as well as other disorders involving dysregulated inflammation and redox homeostasis. In this mini-review, we discuss the latest cutting-edge research discoveries on novel molecular targets of metformin in glycemic control, cardiovascular protection, cancer intervention, anti-inflammation, antiaging, and weight control. Identification of these novel targets and pathways not only deepens our understanding of the molecular mechanisms by which metformin exerts diverse beneficial biological effects, but also provides opportunities for developing new mechanistically based drugs for human diseases.
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Affiliation(s)
- Hong Zhu
- Department of Physiology and Pathophysiology, Jerry M. Wallace School of Osteopathic Medicine, Campbell University SOM, Buies Creek, NC, USA.
| | - Zhenquan Jia
- Department of Biology, College of Arts and Sciences, University of North Carolina, Greensboro, NC, USA
| | - Yunbo Robert Li
- Department of Pharmacology, Jerry M. Wallace School of Osteopathic Medicine, Campbell University, Buies Creek, NC, USA
| | - Igor Danelisen
- Geisinger Commonwealth School of Medicine, Scranton, PA, USA
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4
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Brazill JM, Shin D, Magee K, Majumdar A, Shen IR, Cavalli V, Scheller EL. Knockout of TSC2 in Nav1.8+ neurons predisposes to the onset of normal weight obesity. Mol Metab 2023; 68:101664. [PMID: 36586433 PMCID: PMC9841058 DOI: 10.1016/j.molmet.2022.101664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE Obesity and nutrient oversupply increase mammalian target of rapamycin (mTOR) signaling in multiple cell types and organs, contributing to the onset of insulin resistance and complications of metabolic disease. However, it remains unclear when and where mTOR activation mediates these effects, limiting options for therapeutic intervention. The objective of this study was to isolate the role of constitutive mTOR activation in Nav1.8-expressing peripheral neurons in the onset of diet-induced obesity, bone loss, and metabolic disease. METHODS In humans, loss of function mutations in tuberous sclerosis complex 2 (TSC2) lead to maximal constitutive activation of mTOR. To mirror this in mice, we bred Nav1.8-Cre with TSC2fl/fl animals to conditionally delete TSC2 in Nav1.8-expressing neurons. Male and female mice were studied from 4- to 34-weeks of age and a subset of animals were fed a high-fat diet (HFD) for 24-weeks. Assays of metabolism, body composition, bone morphology, and behavior were performed. RESULTS By lineage tracing, Nav1.8-Cre targeted peripheral sensory neurons, a subpopulation of postganglionic sympathetics, and several regions of the brain. Conditional knockout of TSC2 in Nav1.8-expressing neurons (Nav1.8-TSC2KO) selectively upregulated neuronal mTORC1 signaling. Male, but not female, Nav1.8-TSC2KO mice had a 4-10% decrease in body size at baseline. When challenged with HFD, both male and female Nav1.8-TSC2KO mice resisted diet-induced gains in body mass. However, this did not protect against HFD-induced metabolic dysfunction and bone loss. In addition, despite not gaining weight, Nav1.8-TSC2KO mice fed HFD still developed high body fat, a unique phenotype previously referred to as 'normal weight obesity'. Nav1.8-TSC2KO mice also had signs of chronic itch, mild increases in anxiety-like behavior, and sex-specific alterations in HFD-induced fat distribution that led to enhanced visceral obesity in males and preferential deposition of subcutaneous fat in females. CONCLUSIONS Knockout of TSC2 in Nav1.8+ neurons increases itch- and anxiety-like behaviors and substantially modifies fat storage and metabolic responses to HFD. Though this prevents HFD-induced weight gain, it masks depot-specific fat expansion and persistent detrimental effects on metabolic health and peripheral organs such as bone, mimicking the 'normal weight obesity' phenotype that is of growing concern. This supports a mechanism by which increased neuronal mTOR signaling can predispose to altered adipose tissue distribution, adipose tissue expansion, impaired peripheral metabolism, and detrimental changes to skeletal health with HFD - despite resistance to weight gain.
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Affiliation(s)
- Jennifer M Brazill
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA.
| | - David Shin
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA.
| | - Kristann Magee
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA.
| | - Anurag Majumdar
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA.
| | - Ivana R Shen
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA.
| | - Valeria Cavalli
- Department of Neuroscience, Washington University, Saint Louis, MO, USA; Center of Regenerative Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Hope Center for Neurological Disorders, Washington University School of Medicine, Saint Louis, MO, USA.
| | - Erica L Scheller
- Department of Medicine, Division of Bone and Mineral Diseases, Washington University, Saint Louis, MO, USA; Center of Regenerative Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Cell Biology and Physiology, Washington University, Saint Louis, MO, USA; Department of Biomedical Engineering, Washington University, Saint Louis, MO, USA.
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5
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Stover PJ, Field MS, Brawley HN, Angelin B, Iversen PO, Frühbeck G. Nutrition and stem cell integrity in aging. J Intern Med 2022; 292:587-603. [PMID: 35633146 DOI: 10.1111/joim.13507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Adult stem cells (SCs) represent the regenerative capacity of organisms throughout their lifespan. The maintenance of robust SC populations capable of renewing organs and physiological systems is one hallmark of healthy aging. The local environment of SCs, referred to as the niche, includes the nutritional milieu, which is essential to maintain the quantity and quality of SCs available for renewal and regeneration. There is increased recognition that SCs have unique metabolism and conditional nutrient needs compared to fully differentiated cells. However, the contribution of SC nutrition to overall human nutritional requirements is an understudied and underappreciated area of investigation. Nutrient needs vary across the lifespan and are modified by many factors including individual health, disease, physiological states including pregnancy, age, sex, and during recovery from injury. Although current nutrition guidance is generally derived for apparently healthy populations and to prevent nutritional deficiency diseases, there are increased efforts to establish nutrient-based and food-based recommendations based on reducing chronic disease. Understanding the dynamics of SC nutritional needs throughout the life span, including the role of nutrition in extending biological age by blunting biological systems decay, is fundamental to establishing food and nutrient guidance for chronic disease reduction and health maintenance. This review summarizes a 3-day symposium of the Marabou Foundation (www.marabousymposium.org) held to examine the metabolic properties and unique nutritional needs of adult SCs and their role in healthy aging and age-related chronic disease.
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Affiliation(s)
- P J Stover
- Texas A&M AgriLife Institute for Advancing Health through Agriculture, Texas A&M University, College Station, Texas, USA
| | - M S Field
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, USA
| | - H N Brawley
- Texas A&M AgriLife Institute for Advancing Health through Agriculture, Texas A&M University, College Station, Texas, USA
| | - B Angelin
- Cardiometabolic Unit, Clinical Department of Endocrinology, and Department of Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Stockholm, Sweden
| | - P O Iversen
- Department of Nutrition, University of Oslo, Oslo, Norway
| | - G Frühbeck
- Department of Endocrinology & Nutrition, Clínica Universidad de Navarra, CIBEROBN, IdiSNA, Pamplona, Navarra, Spain
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6
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Metabolic regulation by the intestinal metformin-AMPK axis. Nat Commun 2022; 13:2851. [PMID: 35606343 PMCID: PMC9126964 DOI: 10.1038/s41467-022-30477-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 04/26/2022] [Indexed: 11/08/2022] Open
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7
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Kazmi S, Khan MA, Shamma T, Altuhami A, Assiri AM, Broering DC. Therapeutic nexus of T cell immunometabolism in improving transplantation immunotherapy. Int Immunopharmacol 2022; 106:108621. [DOI: 10.1016/j.intimp.2022.108621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/03/2022] [Accepted: 02/10/2022] [Indexed: 11/26/2022]
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8
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Rohm TV, Keller L, Bosch AJT, AlAsfoor S, Baumann Z, Thomas A, Wiedemann SJ, Steiger L, Dalmas E, Wehner J, Rachid L, Mooser C, Yilmaz B, Fernandez Trigo N, Jauch AJ, Wueest S, Konrad D, Henri S, Niess JH, Hruz P, Ganal-Vonarburg SC, Roux J, Meier DT, Cavelti-Weder C. Targeting colonic macrophages improves glycemic control in high-fat diet-induced obesity. Commun Biol 2022; 5:370. [PMID: 35440795 PMCID: PMC9018739 DOI: 10.1038/s42003-022-03305-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 03/22/2022] [Indexed: 12/13/2022] Open
Abstract
The obesity epidemic continues to worsen worldwide. However, the mechanisms initiating glucose dysregulation in obesity remain poorly understood. We assessed the role that colonic macrophage subpopulations play in glucose homeostasis in mice fed a high-fat diet (HFD). Concurrent with glucose intolerance, pro-inflammatory/monocyte-derived colonic macrophages increased in mice fed a HFD. A link between macrophage numbers and glycemia was established by pharmacological dose-dependent ablation of macrophages. In particular, colon-specific macrophage depletion by intrarectal clodronate liposomes improved glucose tolerance, insulin sensitivity, and insulin secretion capacity. Colonic macrophage activation upon HFD was characterized by an interferon response and a change in mitochondrial metabolism, which converged in mTOR as a common regulator. Colon-specific mTOR inhibition reduced pro-inflammatory macrophages and ameliorated insulin secretion capacity, similar to colon-specific macrophage depletion, but did not affect insulin sensitivity. Thus, pharmacological targeting of colonic macrophages could become a potential therapy in obesity to improve glycemic control. Expansion of pro-inflammatory macrophages in the colon occurs early after high-fat diet initiation, prior to macrophage accumulation in the adipose tissue, in a microbiome-dependent fashion. Macrophage depletion systemically and/or exclusively in the colon improves glucose metabolism.
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Affiliation(s)
- Theresa V Rohm
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Lena Keller
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Angela J T Bosch
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Shefaa AlAsfoor
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Zora Baumann
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | | | - Sophia J Wiedemann
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Laura Steiger
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Elise Dalmas
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Josua Wehner
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Leila Rachid
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Catherine Mooser
- Department of Visceral Surgery und Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Bahtiyar Yilmaz
- Department of Visceral Surgery und Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Nerea Fernandez Trigo
- Department of Visceral Surgery und Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Annaise J Jauch
- Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Stephan Wueest
- Division of Pediatric Endocrinology and Diabetology, and Children's Research Center, University Children's Hospital, University of Zurich, Zurich, Switzerland
| | - Daniel Konrad
- Division of Pediatric Endocrinology and Diabetology, and Children's Research Center, University Children's Hospital, University of Zurich, Zurich, Switzerland
| | - Sandrine Henri
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS, Marseille, France
| | - Jan H Niess
- Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland.,Clarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St. Clara Hospital and University Hospital Basel, Basel, Switzerland
| | - Petr Hruz
- Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland.,Clarunis, Department of Visceral Surgery, University Center for Gastrointestinal and Liver Diseases, St. Clara Hospital and University Hospital Basel, Basel, Switzerland
| | - Stephanie C Ganal-Vonarburg
- Department of Visceral Surgery und Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Julien Roux
- Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Basel, Switzerland
| | - Daniel T Meier
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland.,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland
| | - Claudia Cavelti-Weder
- Clinic of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland. .,Department of Biomedicine (DBM), University of Basel, University Hospital Basel, Basel, Switzerland. .,Department of Endocrinology, Diabetology and Clinical Nutrition, University Hospital Zurich (USZ) and University of Zurich (UZH), Zurich, Switzerland.
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9
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Khodadadi M, Jafari-Gharabaghlou D, Zarghami N. An update on mode of action of metformin in modulation of meta-inflammation and inflammaging. Pharmacol Rep 2022; 74:310-322. [PMID: 35067907 DOI: 10.1007/s43440-021-00334-z] [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: 08/24/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 12/13/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is the most common chronic metabolic condition. Several genetic and environmental factors are involved in developing T2DM. Aging, inflammation, and obesity are the main contributors to the initiation of T2DM. They cause chronic sterile meta-inflammation and insulin resistance, thereby making a person more susceptible to developing T2DM. Metformin, a natural cationic biguanide, is widely used as the first-line treatment of T2DM. The exact action mechanism behind the glucose-lowering effect of metformin is not clear, but, presumably, metformin utilizes a broad spectrum of molecular mechanisms to control blood glucose including decreasing intestinal glucose absorption, inhibition of the hepatic gluconeogenesis, decreasing insulin resistance, etc. Recent studies have shown that metformin exerts its effects through the inhibition of mitochondrial respiratory chain complex 1 and the AMP-activated protein kinase (AMPK) activation, but it has been identified in the other studies that AMPK is not the sole hub in metformin mode of action or there are other unknown mechanisms which are involved and yet to be explored. Therefore, here, we discuss the updated findings of the mechanism of action of metformin that contributes to the meta-inflammation and inflammaging action. It is proposed that figuring out the precise mechanism of action of metformin could improve its application in the fields of obesity, inflammation, aging, and inflammaging.
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Affiliation(s)
- Meysam Khodadadi
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Davoud Jafari-Gharabaghlou
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nosratollah Zarghami
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran. .,Department of Medical Biochemistry, Faculty of Medicine, Istanbul Aydin University, Istanbul, Turkey. .,Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
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10
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Andersen HB, Ialchina R, Pedersen SF, Czaplinska D. Metabolic reprogramming by driver mutation-tumor microenvironment interplay in pancreatic cancer: new therapeutic targets. Cancer Metastasis Rev 2021; 40:1093-1114. [PMID: 34855109 DOI: 10.1007/s10555-021-10004-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 11/22/2021] [Indexed: 12/12/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers globally with a mortality rate exceeding 95% and very limited therapeutic options. A hallmark of PDAC is its acidic tumor microenvironment, further characterized by excessive fibrosis and depletion of oxygen and nutrients due to poor vascularity. The combination of PDAC driver mutations and adaptation to this hostile environment drives extensive metabolic reprogramming of the cancer cells toward non-canonical metabolic pathways and increases reliance on scavenging mechanisms such as autophagy and macropinocytosis. In addition, the cancer cells benefit from metabolic crosstalk with nonmalignant cells within the tumor microenvironment, including pancreatic stellate cells, fibroblasts, and endothelial and immune cells. Increasing evidence shows that this metabolic rewiring is closely related to chemo- and radioresistance and immunosuppression, causing extensive treatment failure. Indeed, stratification of human PDAC tumors into subtypes based on their metabolic profiles was shown to predict disease outcome. Accordingly, an increasing number of clinical trials target pro-tumorigenic metabolic pathways, either as stand-alone treatment or in conjunction with chemotherapy. In this review, we highlight key findings and potential future directions of pancreatic cancer metabolism research, specifically focusing on novel therapeutic opportunities.
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Affiliation(s)
- Henriette Berg Andersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Renata Ialchina
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Stine Falsig Pedersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark.
| | - Dominika Czaplinska
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark
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11
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Kubra KT, Uddin MA, Akhter MS, Leo AJ, Siejka A, Barabutis N. P53 mediates the protective effects of metformin in inflamed lung endothelial cells. Int Immunopharmacol 2021; 101:108367. [PMID: 34794886 DOI: 10.1016/j.intimp.2021.108367] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/26/2021] [Accepted: 11/09/2021] [Indexed: 02/08/2023]
Abstract
The endothelial barrier regulates interstitial fluid homeostasis by transcellular and paracellular means. Dysregulation of this semipermeable barrier may lead to vascular leakage, edema, and accumulation of pro-inflammatory cytokines, inducing microvascular hyperpermeability. Investigating the molecular pathways involved in those events will most probably provide novel therapeutic possibilities in pathologies related to endothelial barrier dysfunction. Metformin (MET) is an anti-diabetic drug, opposes malignancies, inhibits cellular transformation, and promotes cardiovascular protection. In the current study, we assess the protective effects of MET in LPS-induced lung endothelial barrier dysfunction and evaluate the role of P53 in mediating the beneficial effects of MET in the vasculature. We revealed that this biguanide (MET) opposes the LPS-induced dysregulation of the lung microvasculature, since it suppressed the formation of filamentous actin stress fibers, and deactivated cofilin. To investigate whether P53 is involved in those phenomena, we employed the fluorescein isothiocyanate (FITC) - dextran permeability assay, to measure paracellular permeability. Our observations suggest that P53 inhibition increases paracellular permeability, and MET prevents those effects. Our results contribute towards the understanding of the lung endothelium and reveal the significant role of P53 in the MET-induced barrier enhancement.
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Affiliation(s)
- Khadeja-Tul Kubra
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, LA 71201, USA
| | - Mohammad A Uddin
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, LA 71201, USA
| | - Mohammad S Akhter
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, LA 71201, USA
| | - Antoinette J Leo
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, LA 71201, USA
| | - Agnieszka Siejka
- Department of Clinical Endocrinology, Medical University of Lodz, Lodz, Poland
| | - Nektarios Barabutis
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe, LA 71201, USA.
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12
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Liu J, Xiao L, Nie H, Pan Y, Liu Y, Zhang Z, Lin X, Zhang Y, Cai J, Yang M, Liu Y, Zhang L, Xu A, Zhu C. Microecological preparation combined with an modified low-carbon diet improves glucolipid metabolism and cardiovascular complication in obese patients. Diabetol Metab Syndr 2021; 13:77. [PMID: 34256811 PMCID: PMC8276426 DOI: 10.1186/s13098-021-00697-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 07/02/2021] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE To investigate the impact of microecological preparation combined with modified low-carbon diet on the glucolipid metabolism and cardiovascular complication in obese patients. METHODS From August 2017 to July 2020, 66 obese patients were recruited, and administrated with an modified low-carbon diet with (group A) or without (Group B) microecology preparation and a balanced diet in control group (group C) for 6 months. Meanwhile, 20 volunteers administrated with a balanced diet were recruited as the healthy control group (group D). RESULTS After 6-month intervention, obese subjects in group A and B showed significant improvement of body and liver fat mass, reduction of serum lipid levels, intestinal barrier function markers, insulin resistance index (IRI), high blood pressure (HBP) and carotid intima thickness, as compared with subjects in group C. More importantly, subjects in group A had better improvement of vascular endothelial elasticity and intimal thickness than subjects in group B. However, these intervention had no effect on carotid atherosclerotic plaque. CONCLUSION Administration of microecological preparation combined with modified low-carbon diet had better improvement of intestinal barrier function, glucose and lipid metabolism, and cardiovascular complications than low-carbon diet in obese patients, but the effect of a simple low-carb diet on carotid atherosclerotic plaque need to be further addressed.
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Affiliation(s)
- Jianguo Liu
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Liehui Xiao
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Hezhongrong Nie
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Yong Pan
- Department of Pathophysiology, School of Basic Medical Sciences, Shenzhen University, Guangdong, Shenzhen, 518000, China
| | - Yan Liu
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Zhentian Zhang
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Xiuping Lin
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Yuan Zhang
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Jinchuang Cai
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Muxiu Yang
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Yajing Liu
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China
| | - Leijun Zhang
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China.
| | - Aimin Xu
- Department of Medicine, University of Hong Kong, Shenzhen, Hong Kong, China.
- State Key Laboratory of Pharmaceutical Biotechnology, Shenzhen, Hong Kong, China.
| | - Cuifeng Zhu
- Shenzhen Hospital of Southern Medical University, University of Hong Kong, Shenzhen, China.
- Department of Medicine, University of Hong Kong, Shenzhen, Hong Kong, China.
- State Key Laboratory of Pharmaceutical Biotechnology, Shenzhen, Hong Kong, China.
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13
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Olivier S, Pochard C, Diounou H, Castillo V, Divoux J, Alcantara J, Leclerc J, Guilmeau S, Huet C, Charifi W, Varin TV, Daniel N, Foretz M, Neunlist M, Salomon BL, Ghosh P, Marette A, Rolli-Derkinderen M, Viollet B. Deletion of intestinal epithelial AMP-activated protein kinase alters distal colon permeability but not glucose homeostasis. Mol Metab 2021; 47:101183. [PMID: 33548500 PMCID: PMC7921883 DOI: 10.1016/j.molmet.2021.101183] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/21/2021] [Accepted: 02/01/2021] [Indexed: 12/11/2022] Open
Abstract
Objective The intestinal epithelial barrier (IEB) restricts the passage of microbes and potentially harmful substances from the lumen through the paracellular space, and rupture of its integrity is associated with a variety of gastrointestinal disorders and extra-digestive diseases. Increased IEB permeability has been linked to disruption of metabolic homeostasis leading to obesity and type 2 diabetes. Interestingly, recent studies have uncovered compelling evidence that the AMP-activated protein kinase (AMPK) signaling pathway plays an important role in maintaining epithelial cell barrier function. However, our understanding of the function of intestinal AMPK in regulating IEB and glucose homeostasis remains sparse. Methods We generated mice lacking the two α1 and α2 AMPK catalytic subunits specifically in intestinal epithelial cells (IEC AMPK KO) and determined the physiological consequences of intestinal-specific deletion of AMPK in response to high-fat diet (HFD)-induced obesity. We combined histological, functional, and integrative analyses to ascertain the effects of gut AMPK loss on intestinal permeability in vivo and ex vivo and on the development of obesity and metabolic dysfunction. We also determined the impact of intestinal AMPK deletion in an inducible mouse model (i-IEC AMPK KO) by measuring IEB function, glucose homeostasis, and the composition of gut microbiota via fecal 16S rRNA sequencing. Results While there were no differences in in vivo intestinal permeability in WT and IEC AMPK KO mice, ex vivo transcellular and paracellular permeability measured in Ussing chambers was significantly increased in the distal colon of IEC AMPK KO mice. This was associated with a reduction in pSer425 GIV phosphorylation, a marker of leaky gut barrier. However, the expression of tight junction proteins in intestinal epithelial cells and pro-inflammatory cytokines in the lamina propria were not different between genotypes. Although the HFD-fed AMPK KO mice displayed suppression of the stress polarity signaling pathway and a concomitant increase in colon permeability, loss of intestinal AMPK did not exacerbate body weight gain or adiposity. Deletion of AMPK was also not sufficient to alter glucose homeostasis or the acute glucose-lowering action of metformin in control diet (CD)- or HFD-fed mice. CD-fed i-IEC AMPK KO mice also presented higher permeability in the distal colon under homeostatic conditions but, surprisingly, this was not detected upon HFD feeding. Alteration in epithelial barrier function in the i-IEC AMPK KO mice was associated with a shift in the gut microbiota composition with higher levels of Clostridiales and Desulfovibrionales. Conclusions Altogether, our results revealed a significant role of intestinal AMPK in maintaining IEB integrity in the distal colon but not in regulating glucose homeostasis. Our data also highlight the complex interaction between gut microbiota and host AMPK. Deletion of intestinal AMPKα1 and α2 suppresses the stress-polarity signaling (SPS) pathway. Loss of the SPS pathway is associated with increased paracellular permeability in the distal colon. Intestinal AMPK is dispensable for the acute glucose-lowering action of metformin. Loss of intestinal AMPK alters the gut microbiota composition.
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Affiliation(s)
- Séverine Olivier
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Camille Pochard
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Hanna Diounou
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Vanessa Castillo
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Jordane Divoux
- Sorbonne Université, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI), Paris, France
| | - Joshua Alcantara
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Jocelyne Leclerc
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Sandra Guilmeau
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Camille Huet
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Wafa Charifi
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Thibault V Varin
- Québec Heart and Lung Research Institute (IUCPQ) & Institute for Nutrition and Functional Foods (INAF), Laval University Québec, Québec, Canada
| | - Noëmie Daniel
- Québec Heart and Lung Research Institute (IUCPQ) & Institute for Nutrition and Functional Foods (INAF), Laval University Québec, Québec, Canada
| | - Marc Foretz
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Michel Neunlist
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Benoit L Salomon
- Sorbonne Université, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI), Paris, France
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA; Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - André Marette
- Québec Heart and Lung Research Institute (IUCPQ) & Institute for Nutrition and Functional Foods (INAF), Laval University Québec, Québec, Canada
| | - Malvyne Rolli-Derkinderen
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.
| | - Benoit Viollet
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.
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14
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Abstract
Sensing and responding to changes in nutrient levels, including those of glucose, lipids, and amino acids, by the body is necessary for survival. Accordingly, perturbations in nutrient sensing are tightly linked with human pathologies, particularly metabolic diseases such as obesity, type 2 diabetes mellitus, and other complications of metabolic syndromes. The conventional view is that amino acids are fundamental elements for protein and peptide synthesis, while recent studies have revealed that amino acids are also important bioactive molecules that play key roles in signaling pathways and metabolic regulation. Different pathways that sense intracellular and extracellular levels of amino acids are integrated and coordinated at the organismal level, and, together, these pathways maintain whole metabolic homeostasis. In this review, we discuss the studies describing how important sensing signals respond to amino acid availability and how these sensing mechanisms modulate metabolic processes, including energy, glucose, and lipid metabolism. We further discuss whether dysregulation of amino acid sensing signals can be targeted to promote metabolic disorders, and discuss how to translate these mechanisms to treat human diseases. This review will help to enhance our overall understanding of the correlation between amino acid sensing and metabolic homeostasis, which have important implications for human health.
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Affiliation(s)
- Xiaoming Hu
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Feifan Guo
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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15
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Fritsch SD, Weichhart T. Metabolic and immunologic control of intestinal cell function by mTOR. Int Immunol 2020; 32:455-465. [PMID: 32140726 DOI: 10.1093/intimm/dxaa015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 02/28/2020] [Indexed: 02/06/2023] Open
Abstract
The intestinal epithelium is one of the most quickly dividing tissues in our body, combining the absorptive advantages of a single layer with the protection of a constantly renewing barrier. It is continuously exposed to nutrients and commensal bacteria as well as microbial and host-derived metabolites, but also to hazards such as pathogenic bacteria and toxins. These environmental cues are sensed by the mucosa and a vast repertory of immune cells, especially macrophages. A disruption of intestinal homeostasis in terms of barrier interruption can lead to inflammatory bowel diseases and colorectal cancer, and macrophages have an important role in restoring epithelial function following injury. The mammalian/mechanistic target of rapamycin (mTOR) signalling pathway senses environmental cues and integrates metabolic responses. It has emerged as an important regulator of intestinal functions in homeostasis and disease. In this review, we are going to discuss intestinal mTOR signalling and metabolic regulation in different intestinal cell populations with a special focus on immune cells and their actions on intestinal function.
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Affiliation(s)
- Stephanie D Fritsch
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Währinger Straße, Vienna, Austria
| | - Thomas Weichhart
- Center of Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, Währinger Straße, Vienna, Austria
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16
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Obesity and Related Type 2 Diabetes: A Failure of the Autonomic Nervous System Controlling Gastrointestinal Function? GASTROINTESTINAL DISORDERS 2020. [DOI: 10.3390/gidisord2040039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The pandemic spread of obesity and type 2 diabetes is a serious health problem that cannot be contained with common therapies. At present, the most effective therapeutic tool is metabolic surgery, which substantially modifies the gastrointestinal anatomical structure. This review reflects the state of the art research in obesity and type 2 diabetes, describing the probable reason for their spread, how the various brain sectors are involved (with particular emphasis on the role of the vagal system controlling different digestive functions), and the possible mechanisms for the effectiveness of bariatric surgery. According to the writer’s interpretation, the identification of drugs that can modulate the activity of some receptor subunits of the vagal neurons and energy-controlling structures of the central nervous system (CNS), and/or specific physical treatment of cortical areas, could reproduce, non-surgically, the positive effects of metabolic surgery.
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17
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Funk MC, Zhou J, Boutros M. Ageing, metabolism and the intestine. EMBO Rep 2020; 21:e50047. [PMID: 32567155 PMCID: PMC7332987 DOI: 10.15252/embr.202050047] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/18/2020] [Accepted: 05/29/2020] [Indexed: 12/14/2022] Open
Abstract
The intestinal epithelium serves as a dynamic barrier to the environment and integrates a variety of signals, including those from metabolites, commensal microbiota, immune responses and stressors upon ageing. The intestine is constantly challenged and requires a high renewal rate to replace damaged cells in order to maintain its barrier function. Essential for its renewal capacity are intestinal stem cells, which constantly give rise to progenitor cells that differentiate into the multiple cell types present in the epithelium. Here, we review the current state of research of how metabolism and ageing control intestinal stem cell function and epithelial homeostasis. We focus on recent insights gained from model organisms that indicate how changes in metabolic signalling during ageing are a major driver for the loss of stem cell plasticity and epithelial homeostasis, ultimately affecting the resilience of an organism and limiting its lifespan. We compare findings made in mouse and Drosophila and discuss differences and commonalities in the underlying signalling pathways and mechanisms in the context of ageing.
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Affiliation(s)
- Maja C Funk
- Division Signaling and Functional Genomics, German Cancer Research Center (DKFZ), Heidelberg University, Heidelberg, Germany
| | - Jun Zhou
- Division Signaling and Functional Genomics, German Cancer Research Center (DKFZ), Heidelberg University, Heidelberg, Germany
| | - Michael Boutros
- Division Signaling and Functional Genomics, German Cancer Research Center (DKFZ), Heidelberg University, Heidelberg, Germany
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18
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van Keulen P, Khan MA, Dijkstra J, Knol F, McCoard SA. Effect of arginine or glutamine supplementation and milk feeding allowance on small intestine development in calves. J Dairy Sci 2020; 103:4754-4764. [PMID: 32197854 DOI: 10.3168/jds.2019-17529] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 01/24/2020] [Indexed: 01/05/2023]
Abstract
The development of the small intestine (SI) is important for the health and growth of neonatal calves. This study evaluated the effect of arginine (Arg) and glutamine (Gln) supplementation and 2 levels of milk allowance on the histomorphological development of the SI in preweaning calves. Sixty mixed-sex Friesian × Jersey calves (3-5 d of age) were offered reconstituted whole milk (125 g/L, 26% fat, 26% protein) at either high (20% of arrival body weight/d; HM) or low (10% of arrival body weight/d; LM) milk allowance without (Ctrl) or with supplementary Arg or Gln (at 1% of milk dry matter) in a 2 × 3 factorial design (n = 10/treatment). After 35 d on the diets, all calves were slaughtered to collect tissues for examination of SI development. Calves in the HM group had higher milk intake, total weight gain, and average daily gain compared with LM calves, but no effect of AA supplementation nor an interaction between milk allowance and AA supplementation was observed. For the duodenum, we observed an AA by milk allowance interaction for villus height and width, and goblet cell number per villus (HM-Arg > HM-Gln > HM-Ctrl), and villus height to crypt depth ratio (HM-Arg > HM-Gln = HM-Ctrl), but no effect of AA supplementation in the LM group. Goblet cell numbers per 100 µm of SI were greater in Arg-supplemented calves than in unsupplemented controls, with Gln-supplemented calves intermediate to but not different from the other groups. Epithelium thickness was greater in LM than in HM calves. Villus density, crypt depth, and muscle thickness did not differ between groups. For the jejunum, there was an AA by milk allowance interaction for villus height, villus surface area, and villus height to crypt depth ratio (HM-Arg = HM-Gln > HM-Ctrl), with no effect of AA supplementation in the LM groups. Amino acid supplementation affected goblet cell number per villus (HM-Gln > HM-Ctrl calves, HM-Arg intermediate), and both LM-Arg and LM-Gln calves had greater numbers than LM-Ctrl calves. Villus width, crypt depth, and muscle thickness were greater in HM than LM calves but there was no effect of AA supplementation. Villus density, goblet cell number per 100 µm of SI, and epithelium thickness were unaffected by AA supplementation and milk allowance. Milk allowance and AA supplementation had no effect on SI morphology in the ileum. Increasing milk allowance improved villus height, width, and surface area but only in Arg- or Gln-supplemented calves, not in control calves. The observed changes in development may be important for intestinal functionality, integrity, and barrier function in preweaning calves, potentially through increased cell growth and proliferation or reduced levels of cellular atrophy.
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Affiliation(s)
- P van Keulen
- Animal Nutrition and Physiology Team, AgResearch Grasslands Ltd., Palmerston North 4474, New Zealand; Animal Nutrition Group, Wageningen University and Research, 6700 AH Wageningen, the Netherlands
| | - M A Khan
- Animal Nutrition and Physiology Team, AgResearch Grasslands Ltd., Palmerston North 4474, New Zealand
| | - J Dijkstra
- Animal Nutrition Group, Wageningen University and Research, 6700 AH Wageningen, the Netherlands
| | - F Knol
- Animal Nutrition and Physiology Team, AgResearch Grasslands Ltd., Palmerston North 4474, New Zealand
| | - S A McCoard
- Animal Nutrition and Physiology Team, AgResearch Grasslands Ltd., Palmerston North 4474, New Zealand.
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19
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Pharmacology of metformin - An update. Eur J Pharmacol 2019; 865:172782. [PMID: 31705902 DOI: 10.1016/j.ejphar.2019.172782] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/24/2019] [Accepted: 11/04/2019] [Indexed: 02/06/2023]
Abstract
Despite being a successful diabetes type 2 drug for more than a half-century in Europe, the mode of action of metformin is still debated. It is the purpose of this review to inform the reader about most recent findings for metformin with respect to its antidiabetic activity as well as proposed benefits beyond glucose control in humans. Clinical evidence now suggests that most of metformin benefits originate from its actions in the gut, involving hormone signaling by glucagon-like peptide 1 and peptide YY. Growth differentiation factor 15, also mainly produced in the gut, was first identified as a biomarker for metformin use but is now suggested to play a significant role in e.g. weight loss of prediabetics. The pharmacokinetics of the drug in humans as basis for pharmacodynamics, resulting in high tissue levels of the intestinal wall, including the colon, proven by biopsies, is presented. A critical survey of metformin actions on mitochondria, increasing the AMP/ATP ratio but also acting as a mild uncoupler, and of postulated new cellular targets (lysosomes) is included.
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