Resveratrol intervention attenuates chylomicron secretion via repressing intestinal FXR-induced expression of scavenger receptor SR-B1.

Two common features of dietary polyphenols have hampered our mechanistic understanding of their beneficial effects for decades: targeting multiple organs and extremely low bioavailability. We show here that resveratrol intervention (REV-I) in high-fat diet (HFD)-challenged male mice inhibits chylomicron secretion, associated with reduced expression of jejunal but not hepatic scavenger receptor class B type 1 (SR-B1). Intestinal mucosa-specific SR-B1-/- mice on HFD-challenge exhibit improved lipid homeostasis but show virtually no further response to REV-I. SR-B1 expression in Caco-2 cells cannot be repressed by pure resveratrol compound while fecal-microbiota transplantation from mice on REV-I suppresses jejunal SR-B1 in recipient mice. REV-I reduces fecal levels of bile acids and activity of fecal bile-salt hydrolase. In Caco-2 cells, chenodeoxycholic acid treatment stimulates both FXR and SR-B1. We conclude that gut microbiome is the primary target of REV-I, and REV-I improves lipid homeostasis at least partially via attenuating FXR-stimulated gut SR-B1 elevation.

Short-term semaglutide treatment improves FGF21 responsiveness in primary hepatocytes isolated from high fat diet challenged mice.

Metabolic functions of GLP-1 and its analogues have been extensively investigated. In addition to acting as an incretin and reducing body weight, we and others have suggested the existence of GLP-1/fibroblast growth factor 21 (FGF21) axis in which liver mediates certain functions of GLP-1 receptor agonists. In a more recent study, we found with surprise that four-week treatment with liraglutide but not semaglutide stimulated hepatic FGF21 expression in HFD-challenged mice. We wondered whether semaglutide can also improve FGF21 sensitivity or responsiveness and hence triggers the feedback loop in attenuating its stimulation on hepatic FGF21 expression after a long-term treatment. Here, we assessed effect of daily semaglutide treatment in HFD-fed mice for 7 days. HFD challenge attenuated effect of FGF21 treatment on its downstream events in mouse primary hepatocytes, which can be restored by 7-day semaglutide treatment. In mouse liver, 7-day semaglutide treatment stimulated FGF21 as well as genes that encode its receptor (FGFR1) and the obligatory co-receptor (KLB), and a battery of genes that are involved in lipid homeostasis. In epididymal fat tissue, expressions of a battery genes including Klb affected by HFD challenge were reversed by 7-day semaglutide treatment. We suggest that semaglutide treatment improves FGF21 sensitivity which is attenuated by HFD challenge.

The anti-inflammatory feature of glucagon-like peptide-1 and its based diabetes drugs-Therapeutic potential exploration in lung injury.

Since 2005, GLP-1 receptor (GLP-1R) agonists (GLP-1RAs) have been developed as therapeutic agents for type 2 diabetes (T2D). GLP-1R is not only expressed in pancreatic islets but also other organs, especially the lung. However, controversy on extra-pancreatic GLP-1R expression still needs to be further resolved, utilizing different tools including the use of more reliable GLP-1R antibodies in immune-staining and co-immune-staining. Extra-pancreatic expression of GLP-1R has triggered extensive investigations on extra-pancreatic functions of GLP-1RAs, aiming to repurpose them into therapeutic agents for other disorders. Extensive studies have demonstrated promising anti-inflammatory features of GLP-1RAs. Whether those features are directly mediated by GLP-1R expressed in immune cells also remains controversial. Following a brief review on GLP-1 as an incretin hormone and the development of GLP-1RAs as therapeutic agents for T2D, we have summarized our current understanding of the anti-inflammatory features of GLP-1RAs and commented on the controversy on extra-pancreatic GLP-1R expression. The main part of this review is a literature discussion on GLP-1RA utilization in animal models with chronic airway diseases and acute lung injuries, including studies on the combined use of mesenchymal stem cell (MSC) based therapy. This is followed by a brief summary.

Liraglutide stimulates the ß-catenin signaling cascade in mouse epididymal fat tissue.

Although canonical Wnt signaling pathway activation was shown to negatively regulate adipogenesis, recent investigations suggest that Wnt pathway effectors TCF7L2 and ß-catenin (ß-cat) in adipose tissues are also involved in energy homeostasis during adulthood. In assessing the metabolic beneficial effect of GLP-1-based diabetes drugs in high-fat diet (HFD)-challenged mice, we observed that liraglutide treatment affected the expression of a battery of adipose tissue-specific genes, including those that encode adiponectin and leptin, mainly in epididymal white adipose tissue (eWAT). Fourteen-week HFD challenge repressed TCF7L2 and ß-cat S675 phosphorylation in eWAT, while such repression was reversed by liraglutide treatment (150 µg/kg body weight daily) during weeks 10-14. In Glp1r-/-mice, liraglutide failed in stimulating TCF7L2 or ß-cat in eWAT. We detected Glp1r expression in mouse eWAT and its level is enriched in its stromal vascular fraction (SVF). Mouse eWAT-SVF showed reduced expression of Tcf7l2 and its Tcf7l2 level could not be stimulated by liraglutide treatment; while following adipogenic differentiation, rat eWAT-SVF showed elevated Tcf7l2 expression. Direct in vitro liraglutide treatment in eWAT-SVF stimulated CREB S133, ß-cat S675 phosphorylation, and cellular cAMP level. Thus, cAMP/ß-cat signaling cascade can be stimulated by liraglutide in eWAT via GLP-1R expressed in eWAT-SVF.

Management of cognitive impairment in bipolar disorder: a systematic review of randomized controlled trials.

Cognitive impairment is common in bipolar disorder and is emerging as a therapeutic target to enhance quality of life and function. A systematic search was conducted on PubMed, PsycInfo, Cochrane, clinicaltrials.gov, and Embase databases for blinded or open-label randomized controlled trials evaluating the pro-cognitive effects of pharmacological, neurostimulation, or psychological interventions for bipolar disorder. Twenty-two trials were identified, evaluating a total of 16 different pro-cognitive interventions. The methodological quality of the identified trials were assessed using the Cochrane Risk of Bias tool. Currently, no intervention (i.e., pharmacologic, neurostimulation, cognitive remediation) has demonstrated robust and independent pro-cognitive effects in adults with bipolar disorder. Findings are preliminary and methodological limitations limit the interpretation of results. Methodological considerations including, but not limited to, the enrichment with populations with pre-treatment cognitive impairment, as well as the inclusion of individuals who are in remission are encouraged. Future trials may also consider targeting interventions to specific cognitive subgroups and the use of biomarkers of cognitive function.