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ABSTRACTAlzheimer’s disease (AD) is a debilitating brain disorder with rapidly mounting prevalence worldwide, yet no proven AD cure has been discovered. Using a multi-omics approach in a transgenic AD mouse model, the current study demonstrated the efficacy of a modified Mediterranean-ketogenic diet (MkD) on AD-related neurocognitive pathophysiology and underlying mechanisms related to the gut-microbiome-brain axis. The findings revealed that MkD induces profound shifts in the gut microbiome community and microbial metabolites. Most notably, MkD promoted growth of the Lactobacillus population, resulting in increased bacteria-derived lactate production. We discovered elevated levels of microbiome- and diet-derived metabolites in the serum as well, signaling their influence on the brain. Importantly, these changes in serum metabolites upregulated specific receptors that have neuroprotective effects and induced alternations in neuroinflammatory-associated pathway profiles in hippocampus. Additionally, these metabolites displayed strong favorable co-regulation relationship with gut-brain integrity and inflammatory markers, as well as neurobehavioral outcomes. The findings underscore the ameliorative effects of MkD on AD-related neurological function and the underlying gut-brain communication via modulation of the gut microbiome-metabolome arrays.

Akkermansia muciniphila (A. muciniphila) and its derivatives, including extracellular vesicles (EVs) and outer membrane proteins, are recognized for enhancing intestinal balance and metabolic health. However, the mechanisms of Akkermansia muciniphila’s action and its effects on the microbiome are not well understood. In this study, we examined the influence of A. muciniphila and its derivatives on gastrointestinal (GI) and metabolic disorders through a meta-analysis of studies conducted on mouse models. A total of 39 eligible studies were identified through targeted searches on PubMed, Web of Science, Science Direct, and Embase until May 2024. A. muciniphila (alive or heat-killed) and its derivatives positively affected systemic and gut inflammation, liver enzyme level, glycemic response, and lipid profiles. The intervention increased the expression of tight-junction proteins in the gut, improving gut permeability in mouse models of GI and metabolic disorders. Regarding body weight, A. muciniphila and its derivatives prevented weight loss in animals with GI disorders while reducing body weight in mice with metabolic disorders. Sub-group analysis indicated that live bacteria had a more substantial effect on most analyzed biomarkers. Gut microbiome analysis using live A. muciniphila identified a co-occurrence cluster, including Desulfovibrio, Family XIII AD3011 group, and Candidatus Saccharimonas. Thus, enhancing the intestinal abundance of A. muciniphila and its gut microbial clusters may provide more robust health benefits for cardiometabolic, and age-related diseases compared with A. muciniphila alone. The mechanistic insight elucidated here will pave the way for further exploration and potential translational applications in human health.

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease, entails chronic inflammation of the gastrointestinal tract. The pathogenesis of IBD implicates genetic factors, gut microbiome alterations, and immune dysregulation, contributing to its increasing global prevalence. The sturgeon-derived peptide, which exhibits promising anti-inflammatory effects, provides potential therapeutic insights for managing IBD symptoms. This study aims to elucidate the therapeutic mechanisms of novel sturgeon-derived peptide (LLLE, Leu-Leu-Leu-Glu) by investigating their effects on intestinal inflammation, gut microbiota composition, and fecal metabolites in a mouse model of IBD. LLLE administration alleviated weight loss and disease activity index (DAI) scores in dextran sulfate sodium salt (DSS)-induced colitis in mice. Histopathological examination showed LLLE pretreatment improved colon morphology and histopathological condition and decreased serum interleukin-6 (IL-6) levels. 16S rRNA sequencing indicated LLLE-modulation of gut microbiota, especially alleviated DSS-elevated Bacteroidetes. Fecal metabolomic analysis unveiled that LLLE restores critical metabolites such as indole-3-propionic acid, which is pivotal in anti-inflammatory responses. Altogether, sturgeon peptide exhibits considerable promise as a therapeutic agent for colitis, owing to its anti-inflammatory effects, modulation of gut microbiota, and restoration of essential fecal metabolites.

The hormone adiponectin has many beneficial effects in atherosclerosis, as gene deficiency in adiponectin or its receptor has shown detrimental effects on plaque burden in mice. Our objective was to understand the potential roles adiponectin deficiency has on aortic plaque content, inflammation, and markers of cardiovascular disease according to sex and age. To study the influence of adiponectin status on sex and atherosclerosis, we used young male and female adipoq−/−apoe−/−, adipoq+/−apoe−/−, and apoe−/− mice, which were given a high-fat diet (HFD). Even a 50% reduction in the expression of adiponectin led to a plaque reduction in males and an increase in females compared with apoe−/− controls. Changes in plaque were not attributed to changes in cholesterol or cardiovascular disease markers but correlated with inflammatory markers. Plaque reduction in males was associated with reduced monocyte chemoattractant protein 1 (MCP1) and increased colony stimulating factor 3 (CSF3), while the increase in plaque in females correlated with the opposite effect in these markers. In old mice, both adiponectin-deficient genotypes and sexes accumulated more plaque than their respective apoe−/− controls. The increase in plaque with adiponectin deficiency according to age was not explained by a worsening lipid profile but correlated with increased levels of C-C motif chemokine ligand 5 (CCL5). Overall, our study uncovered genotype-specific effects that differed by sex and age of adiponectin deficiency in atherosclerosis.

Adiponectin (adipoq), the most abundant hormone in circulation, has many beneficial effects on the cardiovascular system, in part by preserving the contractile phenotype of vascular smooth muscle cells (VSMCs). However, the lack of adiponectin or its receptor and treatment with recombinant adiponectin have shown contradictory effects on plaque in mice. RNA sequence of Adipoq+/+ and adipoq−/− VSMCs from male aortas identified a critical role for adiponectin in AKT signaling, the extracellular matrix (ECM), and TGF-β signaling. Upregulation of AKT activity mediated proliferation and migration of adipoq−/− cells. Activation of AMPK with metformin or AdipoRon reduced AKT-dependent proliferation and migration of adipoq−/− cells but did not improve the expression of contractile genes. Adiponectin deficiency impaired oxidative phosphorylation (OXPHOS), increased expression of glycolytic enzymes, and elevated mitochondrial reactive oxygen species (ROS) (superoxide, and hydrogen peroxide). Anti-atherogenic mechanisms targeted the ECM in adipoq−/− cells, downregulating MMP2 and 9 and upregulating decorin (DCN) and elastin (ELN). In vivo, the main sex differences in protein expression in aortas involved a more robust upregulation of MMP3 in females than males. Females also showed a reduction in DCN, which was not affected in males. Our study uncovered the AKT/MAPK/TGF-β network as a central regulator of VSMC phenotype.

Objective This study examined the safety and efficacy of biological agents, especially tumour necrosis factor (TNF) inhibitors, for HIV-positive rheumatology patients refractory to standard therapy.Methods This study is a retrospective case series including patients derived from a community HIV clinic as well as from two academic centres. Initial visit data collected included: sociodemographic characteristics, CD4 counts, HIV viral load and medication use. Patients with persistent disease activity despite standard conservative therapy were begun on biological agents.The main outcomes were patient and physician global assessment of treatment response and medication side effects in patients with rheumatological disorders treated with biological medications over time.Results Seventeen patients were seen from 2003 to 2021, including eight from our previous cohort published in 2008 and nine seen since then, five of whom taking TNF blockers for more than 10 years. Three (17.7%) had rheumatoid arthritis, five (29.4%) psoriatic arthritis, four (23.5%) axial spondyloarthritis and the rest (29.4%) peripheral spondyloarthritis. Antiretroviral therapy had been used in 15. All but one had at least a partial response to biological therapy. There were no major infectious episodes necessitating the discontinuation of medications with only one patient discontinuing treatment due to rising HIV viral load. Patients not on antiretroviral therapy reported no adverse side effects from biological therapy. Four patients were switched to ustekinumab, secukinumab, tocilizumab or upadacitinib from anti-TNF therapy without complications.Conclusions These data suggest that biological therapy, especially anti-TNF agents are safe and well tolerated in HIV positive individuals even over several years.