Anti-obesity and hypolipidemic effects of"Jinhua Xiangyuan"tea infusion in high-fat diet-induced obese rats

"Jinhua Xiangyuan"(JHXY)is a unique type of Chinese tea made from roasted oolong tea and subsequently fermented by Eurotium cristatum.In this study,we investigated the potential benefits of JHXY on obese rats induced by a high-sucrose high-fat diet.JHXY infusion was administered orally at 1.6 g/kg·bw(HI),0.8 g/kg·bw(MI),and 0.4 g/kg·bw(LI)per day for 10 weeks.Weight gain was significantly suppressed without affecting appetite.In the MI and HI groups,JHXY led to a significant reduction in triglycerides(TG),total cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C),accompanied by an increase in high-density lipoprotein cholesterol(HDL-C)levels.A significant reduction in white adipose tissue(WAT)index and an increase in brown adipose tissue(BAT)index were observed.In MI group,the morphology of hepatocytes was restored.The abundance of Bifidobacterium was elevated,whereas the abundance of Desulfovibrio was significantly reduced.Correlation analysis revealed that the ratio of Ruminococcus to Bifidobacterium was positively correlated with HDL-C;the abundance of the Christensenellaceae_R-7_group was negatively correlated with TC and LDL-C,while positively correlated with HDL-C;the abundance of Lactobacillus was positively correlated with BAT/WAT ratio.In the MI group,the lipopolysaccharide biosynthesis pathway was predicted to be significantly weakened(p<0.05);in the HI group,the sulfur relay system pathway was attenuated,whereas the bacterial toxins pathway was augmented(p<0.05).Our research showed that JHXY has the potential to enhance metabolic health and maintain intestinal homeostasis.Optimal dosage should be a focal point in future research.

Carbonic anhydrase 2 mediates anti-obesity effects of black tea as thermogenic activator

Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strategy of anti-obesity by dissipating energy as heat.However,drugs based on adipose tissue thermogenesis have not been successfully approved yet.In current study,we found that black tea extract(BTE)obtained by patentauthorized manufacturing process prevented body weight gain as novel thermogenic activator with reduction of adiposity,improvement of adipose distribution,and glucose metabolism improvement in diet-induced obesity mice.Mechanismly,anti-obesity effect of BTE depends on promoting BAT thermogenesis and WAT browning with upregulation of uncoupling protein 1(UCP1),especially visceral adipose tissue(VAT)with browning resistance.Specifically,utilizing in silico approach of network pharmacology and molecular docking,we identified carbonic anhydrase 2(CA2)in nitrogen metabolism as anti-obesity target of BTE and further elucidated that protein kinase B(AKT)signaling pathway linked CA2 and UCP1.Meanwhile gut microbiota regulation may prompt the CA2-dependent thermogenesis activation.Our findings demonstrated anti-obesity effect of BTE as thermogenic activator through CA2-mediated BAT thermogenesis and WAT browning via CA2-AKT-UCP1 signaling pathway,which could be developed as promising anti-obesity agent with good safety and efficacy.

分枝杆菌非典型错配修复及其在抗生素耐药中的研究进展

错配修复(mismatch repair,MMR)是生物体DNA复制后的一种常见修复系统,对于维持基因组稳定性至关重要,其关键步骤由MutS和MutL蛋白家族的成员执行,尽管这种修复途径十分重要,但在许多古菌和放线菌基因组中并不存在MutS或MutL的同源蛋白。这类细菌(例如分枝杆菌等)采用另一种非典型的MMR途径,由核酸内切酶EndoMS/NucS发挥关键作用,与典型MMR蛋白(MutS/MutL)相比没有结构同源性。EndoMS/NucS介导的非典型错配修复在分枝杆菌DNA修复、突变和同源重组以及抗生素耐药等方面发挥重要作用。本文通过对比典型MMR途径和非典型MMR途径,深入阐述了分枝杆菌EndoMS/NucS介导的非典型MMR途径及其最新进展,以期为分枝杆菌错配修复分子机制带来新见解以及对分枝杆菌抗生素治疗提供研究线索。