Project description:Introduction: Chronic sleep fragmentation (SF) is prevalent in contemporary human society, highlighting detrimental effects on glucose metabolism and adipose tissue morphology, which is closely linked to gut microbiota composition. However, it remains unclear whether sleep recovery (SR) after prolonged SF can ameliorate glucose metabolism, influence the transcriptome of inguinal white adipose tissue (iWAT), and whether these effects align with alterations in the gut microbiota. Methods: Mice were subjected to 8 weeks of SF and subsequently allowed 2 weeks of SR. We assessed glucose tolerance through intraperitoneal glucose tolerance tests (ipGTT), analyzed gut microbiota via 16s rDNA amplicon sequencing, and examined transcriptomic alterations in iWAT using RNA sequencing. Results: Despite the two-week SR following chronic SF, significant glucose intolerance persisted, accompanied by subtle shifts in the gut microbiota and alterations in gene expression within iWAT. The top hub genes Ncapg, Cenpe, and Tik were identified from the protein-protein interaction network. Conclusion: Even followed by a brief period of SR, prolonged SF still led to ongoing glucose intolerance and alterations in the adipose tissue transcriptome in mice. These changes were intertwined with modifications in the gut microbiome. The shifts in gut microbiota may play a pivotal role in understanding the sustained negative effects of SF.
2024-06-30 | GSE248189 | GEO
Project description:Gut microbiome in chronic systolic heart failure
Project description:Chronic diseases arise when pathophysiological processes achieve a steady state by self-reinforcing. Here, we explored the possibility of a self-reinforcement state in a common condition, chronic constipation, where alterations of the gut microbiota have been reported. The functional impact of the microbiota shifts on host physiology remains unclear, however we hypothesized that microbial communities adapted to slow gastrointestinal transit affect host functions in a way that reinforces altered transit, thereby maintaining the advantage for microbial self-selection. To test this, we examined the impact of pharmacologically (loperamide)-induced constipation (PIC) on the structural and functional profile of altered gut microbiota. PIC promoted changes in the gut microbiome, characterized by decreased representation of butyrate-producing Clostridiales, decreased cecal butyrate concentration and altered metabolic profiles of gut microbiota. PIC-associated gut microbiota also impacted colonic gene expression, suggesting this might be a basis for decreased gastrointestinal (GI) motor function. Introduction of PIC-associated cecal microbiota into germ-free (GF) mice significantly decreased GI transit time. Our findings therefore support the concept that chronic diseases like constipation are caused by disease-associated steady states, in this case, caused by reciprocating reinforcement of pathophysiological factors in host-microbe interactions. We used microarrays to detail the global gene expression profile in the proximal colon smooth muscle tissues of germ-free, conventionalized, or specific pathogen free mouse C57Bl/6 female and male specific pathogen free (SPF) mice were bred and housed in the animal care facility at the University of Chicago. Mice of 8–10 weeks of age were treated with 0.1% loperamide in the drinking water for 7 days. Age matched, germ-free (GF) C57Bl/6 mice were gavaged orally with cecal luminal contents harvested from control or loperamide-treated C57Bl/6 donor mice. Recipient mice were sacrificed 4 weeks post-colonization.
Project description:Numerous studies found intestinal microbiota alterations which are thought to affect the development of various diseases through the production of gut-derived metabolites. However, the specific metabolites and their pathophysiological contribution to cardiac hypertrophy or heart failure progression still remain unclear. N,N,N-trimethyl-5-aminovaleric acid (TMAVA), derived from trimethyllysine through the gut microbiota, was elevated with gradually increased risk of cardiac mortality and transplantation in a prospective heart failure cohort (n=1647). TMAVA treatment aggravated cardiac hypertrophy and dysfunction in high-fat diet-fed mice. Decreased fatty acid oxidation (FAO) is a hallmark of metabolic reprogramming in the diseased heart and contributes to impaired myocardial energetics and contractile dysfunction. Proteomics uncovered that TMAVA disturbed cardiac energy metabolism, leading to inhibition of FAO and myocardial lipid accumulation. TMAVA treatment altered mitochondrial ultrastructure, respiration and FAO and inhibited carnitine metabolism. Mice with γ-butyrobetaine hydroxylase (BBOX) deficiency displayed a similar cardiac hypertrophy phenotype, indicating that TMAVA functions through BBOX. Finally, exogenous carnitine supplementation reversed TMAVA induced cardiac hypertrophy. These data suggest that the gut microbiota-derived TMAVA is a key determinant for the development of cardiac hypertrophy through inhibition of carnitine synthesis and subsequent FAO.
Project description:Numerous studies found intestinal microbiota alterations which are thought to affect the development of various diseases through the production of gut-derived metabolites. However, the specific metabolites and their pathophysiological contribution to cardiac hypertrophy or heart failure progression still remain unclear. N,N,N-trimethyl-5-aminovaleric acid (TMAVA), derived from trimethyllysine through the gut microbiota, was elevated with gradually increased risk of cardiac mortality and transplantation in a prospective heart failure cohort (n=1647). TMAVA treatment aggravated cardiac hypertrophy and dysfunction in high-fat diet-fed mice. Decreased fatty acid oxidation (FAO) is a hallmark of metabolic reprogramming in the diseased heart and contributes to impaired myocardial energetics and contractile dysfunction. Proteomics uncovered that TMAVA disturbed cardiac energy metabolism, leading to inhibition of FAO and myocardial lipid accumulation. TMAVA treatment altered mitochondrial ultrastructure, respiration and FAO and inhibited carnitine metabolism. Mice with γ-butyrobetaine hydroxylase (BBOX) deficiency displayed a similar cardiac hypertrophy phenotype, indicating that TMAVA functions through BBOX. Finally, exogenous carnitine supplementation reversed TMAVA induced cardiac hypertrophy. These data suggest that the gut microbiota-derived TMAVA is a key determinant for the development of cardiac hypertrophy through inhibition of carnitine synthesis and subsequent FAO.
Project description:Chronic diseases arise when pathophysiological processes achieve a steady state by self-reinforcing. Here, we explored the possibility of a self-reinforcement state in a common condition, chronic constipation, where alterations of the gut microbiota have been reported. The functional impact of the microbiota shifts on host physiology remains unclear, however we hypothesized that microbial communities adapted to slow gastrointestinal transit affect host functions in a way that reinforces altered transit, thereby maintaining the advantage for microbial self-selection. To test this, we examined the impact of pharmacologically (loperamide)-induced constipation (PIC) on the structural and functional profile of altered gut microbiota. PIC promoted changes in the gut microbiome, characterized by decreased representation of butyrate-producing Clostridiales, decreased cecal butyrate concentration and altered metabolic profiles of gut microbiota. PIC-associated gut microbiota also impacted colonic gene expression, suggesting this might be a basis for decreased gastrointestinal (GI) motor function. Introduction of PIC-associated cecal microbiota into germ-free (GF) mice significantly decreased GI transit time. Our findings therefore support the concept that chronic diseases like constipation are caused by disease-associated steady states, in this case, caused by reciprocating reinforcement of pathophysiological factors in host-microbe interactions. We used microarrays to detail the global gene expression profile in the proximal colon smooth muscle tissues of germ-free, conventionalized, or specific pathogen free mouse
Project description:Healthy aging relies on a symbiotic host–microbiota relationship. The age-associated decline of the immune system can pose a threat in this delicate equilibrium. In this work, we investigated how the functional deterioration of T cells can impact host–microbiota symbiosis and gut barrier integrity and the implications of this deterioration for inflammaging, senescence, and health decline. Using the Tfamfl/flCd4Cre mouse model, we found that T cell failure compromised gut immunity leading to a decrease in T follicular and regulatory T (Treg) cells and an accumulation of highly proinflammatory and cytotoxic T cells. These alterations were associated with intestinal barrier disruption and gut dysbiosis. Microbiota depletion or adoptive transfer of total CD4 T cells or a Treg cell–enriched pool prevented gut barrier dysfunction and mitigated premature inflammaging and senescence, ultimately enhancing healthspan in this mouse model. Thus, a competent CD4 T cell compartment is critical to ensure healthier aging by promoting host–microbiota mutualism and gut barrier integrity.
Project description:Healthy aging relies on a symbiotic host–microbiota relationship. The age-associated decline of the immune system can pose a threat in this delicate equilibrium. In this work, we investigated how the functional deterioration of T cells can impact host–microbiota symbiosis and gut barrier integrity and the implications of this deterioration for inflammaging, senescence, and health decline. Using the Tfamfl/flCd4Cre mouse model, we found that T cell failure compromised gut immunity leading to a decrease in T follicular and regulatory T (Treg) cells and an accumulation of highly proinflammatory and cytotoxic T cells. These alterations were associated with intestinal barrier disruption and gut dysbiosis. Microbiota depletion or adoptive transfer of total CD4 T cells or a Treg cell–enriched pool prevented gut barrier dysfunction and mitigated premature inflammaging and senescence, ultimately enhancing healthspan in this mouse model. Thus, a competent CD4 T cell compartment is critical to ensure healthier aging by promoting host–microbiota mutualism and gut barrier integrity.