Mitochondrial function and mitophagy in the elderly: effects of exercise

[EN] Aging is a natural, multifactorial and multiorganic phenomenon wherein there are gradual physiological and pathological changes over time. Aging has been associated with a decrease of autophagy capacity and mitochondrial functions, such as biogenesis, dynamics, and mitophagy. These processes are essential for the maintenance of mitochondrial structural integrity and, therefore, for cell life, since mitochondrial dysfunction leads to an impairment of energy metabolism and increased production of reactive oxygen species, which consequently trigger mechanisms of cellular senescence and apoptotic cell death. Moreover, reduced mitochondrial function can contribute to age-associated disease phenotypes in model organisms and humans. Literature data show beneficial effects of exercise on the impairment of mitochondrial biogenesis and dynamics and on the decrease in the mitophagic capacity associated to aging. Thus, exercise could have effects on the major cell signaling pathways that are involved in the mitochondria quality and quantity control in the elderly. Although it is known that several exercise protocols are able to modify the activity and turnover of mitochondria, further studies are necessary in order to better identify the mechanisms of interaction between mitochondrial functions, aging, and physical activity, as well as to analyze possible factors influencing these processes.S

Intestinal microbiota transplantation to germ-free mice in a in vivo model of nafld associated with a quercetin treatment

15 p.To select mice donors for intestinal microbiota transplantation based on its metabolic phenotype in response to a high fat diet (HFD) and quercetin treatment (Q). Intestinal microbiota. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Quercetin ameliorates dysregulation of lipid metabolism genes via the PI3K/AKT pathway in a diet-induced mouse model of non-alcoholic fatty liver disease

P. 879-893Flavonoids and related compounds seem to have favorable effects on nonalcoholic fatty liver disease (NAFLD) progression, although the exact mechanisms implicated are poorly understood. In this study, we aimed to investigate the effect of the flanovol quercetin on gene expression deregulation involved in the development of NAFLD, as well as the possible implication of phosphatidylinositol 3-kinase (PI3K)/AKT pathway modulatio

Intestinal Microbiota Transplantation From HFD-fed and Quercetin Treated Donors Results in a Complex Metabolic Phenotype Transfer that Modulates Obesity-Related NAFLD in Germ Free Mice

2 p.Intestinal microbiota imbalance and related gut-liver axis activation have been identified as key mechanisms in nonalcoholic fatty liver disease (NAFLD) development. Modulation of intestinal microbiota, through administration of prebiotics or faecal microbiota transplantation, is a promising therapeutic approach for obesity associated diseases including NAFLD. The aim of the present study is to evaluate the benefits of gut microbiota transplantation from donors to germ free mice (GFm) following an experimental treatment with the flavonoid quercetin in a high fat diet (HFD)-based NAFLD model. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Protective effect of quercetin on high-fat diet-induced non-alcoholic fatty liver disease in mice is mediated by modulating intestinal microbiota imbalance and related gut-liver axis activation

60 p.Gut microbiota is involved in obesity, metabolic syndrome and the progression of nonalcoholic fatty liver disease (NAFLD). It has been recently suggested that the flavonoid quercetin may have the ability to modulate the intestinal microbiota composition, suggesting a prebiotic capacity which highlights a great therapeutic potential in NAFLD. The present study aims to investigate benefits of experimental treatment with quercetin on gut microbial balance and related gut-liver axis activation in a nutritional animal model of NAFLD associated to obesity. C57BL/6J mice were challenged with high fat diet (HFD) supplemented or not with quercetin for 16 weeks. HFD induced obesity, metabolic syndrome and the development of hepatic steatosis as main hepatic histological finding. Increased accumulation of intrahepatic lipids was associated with altered gene expression related to lipid metabolism, as a result of deregulation of their major modulators. Quercetin supplementation decreased insulin resistance and NAFLD activity score, by reducing the intrahepatic lipid accumulation through its ability to modulate lipid metabolism gene expression, cytochrome P450 2E1 (CYP2E1)-dependent lipoperoxidation and related lipotoxicity. Microbiota composition was determined via 16S ribosomal RNA Illumina next-generation sequencing. Metagenomic studies revealed HFD-dependent differences at phylum, class and genus levels leading to dysbiosis, characterized by an increase in Firmicutes/Bacteroidetes ratio and in Gram-negative bacteria, and a dramatically increased detection of Helicobacter genus. Dysbiosis was accompanied by endotoxemia, intestinal barrier dysfunction and gut-liver axis alteration and subsequent inflammatory gene overexpression. Dysbiosis-mediated toll-like receptor 4 (TLR-4)-NF-B signaling pathway activation was associated with inflammasome initiation response and reticulum stress pathway induction. Quercetin reverted gut microbiota imbalance and related endotoxemia-mediated TLR-4 pathway induction, with subsequent inhibition of inflammasome response and reticulum stress pathway activation, leading to the blockage of lipid metabolism gene expression deregulation. Our results support the suitability of quercetin as a therapeutic approach for obesity-associated NAFLD via its anti-inflammatory, antioxidant and prebiotic integrative response.Gut microbiota is involved in obesity, metabolic syndrome and the progression of nonalcoholic fatty liver disease (NAFLD). It has been recently suggested that the flavonoid quercetin may have the ability to modulate the intestinal microbiota composition, suggesting a prebiotic capacity which highlights a great therapeutic potential in NAFLD. The present study aims to investigate benefits of experimental treatment with quercetin on gut microbial balance and related gut-liver axis activation in a nutritional animal model of NAFLD associated to obesity. C57BL/6J mice were challenged with high fat diet (HFD) supplemented or not with quercetin for 16 weeks. HFD induced obesity, metabolic syndrome and the development of hepatic steatosis as main hepatic histological finding. Increased accumulation of intrahepatic lipids was associated with altered gene expression related to lipid metabolism, as a result of deregulation of their major modulators. Quercetin supplementation decreased insulin resistance and NAFLD activity score, by reducing the intrahepatic lipid accumulation through its ability to modulate lipid metabolism gene expression, cytochrome P450 2E1 (CYP2E1)-dependent lipoperoxidation and related lipotoxicity. Microbiota composition was determined via 16S ribosomal RNA Illumina next-generation sequencing. Metagenomic studies revealed HFD-dependent differences at phylum, class and genus levels leading to dysbiosis, characterized by an increase in Firmicutes/Bacteroidetes ratio and in Gram-negative bacteria, and a dramatically increased detection of Helicobacter genus. Dysbiosis was accompanied by endotoxemia, intestinal barrier dysfunction and gut-liver axis alteration and subsequent inflammatory gene overexpression. Dysbiosis-mediated toll-like receptor 4 (TLR-4)-NF-B signaling pathway activation was associated with inflammasome initiation response and reticulum stress pathway induction. Quercetin reverted gut microbiota imbalance and related endotoxemia-mediated TLR-4 pathway induction, with subsequent inhibition of inflammasome response and reticulum stress pathway activation, leading to the blockage of lipid metabolism gene expression deregulation. Our results support the suitability of quercetin as a therapeutic approach for obesity-associated NAFLD via its anti-inflammatory, antioxidant and prebiotic integrative respons

Akkermansia spp. mediates protection from obesity-associated NAFLD development in germ free mice following intestinal microbiota transplantation from high fat diet and quercetin treated donors

1 p.Dysbiosis and gut-liver axis alteration have been pointed as important contributors to obesity and non-alcoholic fatty liver disease (NAFLD) development. Modulation of intestinal microbiota (IM) emerge as a promising therapeutic strategy for obesity-associated NAFLD. This study aims to determine the effect of IM transplantation and quercetin supplementation in a high fat diet (HFD)-based NAFLD model in germ free mice (GFm). Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Metabolic Phenotype Transfer Through Gut Microbiota Transplantation from HFD-Fed and Quercetin Treated Donors Modulates Obesity-Related NAFLD in Germ-Free Mice

1 p.Gut microbiota is involved in obesity, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Strategies to modulate it, including faecal transplantation and administration of prebiotics as quercetin, are actively being examined. The present study aims to investigate benefits of experimental gut microbiota transfer from donors to germ-free mice (GFm) in a high-fat diet (HFD)-based NAFLD model. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Effect of exercise on gut microbiota and metabolic status modulation in an in vivo model of early obesity and NAFLD

1 p.Childhood obesity is one of the most serious public health concerns from this century, associated with metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) and gut microbiota alterations. Physical exercise improves obesity and NAFLD progression, modulating the gut microbial balance. We aim to investigate the effect of physical exercise on gut microbiota and the metabolic status of an in vivo model of early obesity, metabolic syndrome, and NAFLD. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Protective effect of quercetin treatment on HFD-induced intestinal dysbiosis and barrier dysfunction in an in vivo model of non-alcoholic fatty liver disease

1 p.Gut microbiota is involved in obesity, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Quercetin may have the ability to modulate the intestinal microbiota composition, suggesting therapeutic potential in NAFLD. The present study aims to investigate the beneficial effect of quercetin treatment on dysbiosis, intestinal barrier dysfunction and gut-liver axis alteration in high-fat diet (HFD)-fed mice. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S

Protective Effect of Quercetin Treatment on Gut Microbiota Imbalance in Obesity-Associated NAFLD in Patients and in HFD-FED Mice

2 p.Gut microbiota is involved in obesity, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Quercetin may modulate the intestinal microbiota composition, suggesting therapeutic potential in NAFLD. The present study aims to establish the role of gut microbiota imbalance in obesity-related NAFLD development in patients and in an in vivo model and to investigate benefits of experimental treatment with quercetin. Resumen de un trabajo resultado del proyecto de investigación financiado por la Consejería de Educación de la Junta de Castilla y León (referencia LE063U16)S