Hydroxysafflor yellow A protects against colitis in mice by suppressing pyroptosis via inhibiting HK1/NLRP3/GSDMD and modulating gut microbiota.

Hydroxysafflor yellow A (HSYA), a chalcone glycoside, is a component of Carthamus tinctorius L. and exerts anti-inflammatory and antioxidative effects. However, the therapeutic effect and the underlying mechanism of HSYA on ulcerative colitis is unclear. This study aimed to investigate the unexplored protective effects and underlying mechanisms of HSYA on UC. In vitro analyses showed that HSYA reduced the secretion of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-6 and inhibited nucleotide-binding and oligomerization domain-like receptor protein 3 (NLRP3)/gasdermin D (GSDMD)-mediated pyroptosis in lipopolysaccharide/ adenosine-5'-triphosphate (LPS/ATP)-stimulated macrophages. Gas chromatography-mass spectrometry (GC-MS) profiling of intracellular metabolites showed that HSYA reduced the increased levels of glucose, glucose 6-phosphate, and lactic acid, and inhibited the increased hexokinase 1 (HK1) expression caused by LPS/ATP stimulation. HK1 shRNA transfection further confirmed that HSYA inhibited the NLRP3/GSDMD-mediated pyroptosis via HK1 downregulation. In vivo analyses showed that HSYA drastically attenuated UC symptoms by relieving body weight loss, a decline in colon length, and inflammatory infiltration in colonic tissues induced by dextran sulfate sodium (DSS). HSYA also reduced the secretion of pro-inflammatory cytokines including IL-1ß, IL-6, TNF-α, and IL-18. Moreover, HSYA inhibited HK1/NLRP3/GSDMD-mediated pyroptosis in DSS-induced colitis mice. Finally, 16S rRNA sequencing analyses of gut microbiota revealed that HSYA reversed gut microbiota dysbiosis by reducing the abundance of Proteobacteria and increasing that of Bacteroidetes. This study demonstrated that HSYA not only exerted anti-inflammatory effects by inhibiting HK1/NLRP3/GSDMD and suppressing pyroptosis but also regulated gut microbiota in mice with DSS-induced colitis. Our findings provide new experimental evidence that HSYA might be a potential candidate for treating inflammatory bowel diseases.

Cordycepin exhibits anti-fatigue effect via activating TIGAR/SIRT1/PGC-1α signaling pathway.

Fatigue, a most commonly sub-health condition, may cause people more susceptible to many diseases. Cordycepin, a principal active ingredient from Cordyceps militaris, exerts various pharmacological activities including anti-diabetes, anti-inflammatory, immunomodulatory and antioxidant effects. However, the anti-fatigue effect of cordycepin and specific mechanism remained unclear. This study aimed to investigate the beneficial effect of cordycepin on physical fatigue and elucidate the potential mechanism. 20 mg/kg, 40 mg/kg of cordycepin and 500 mg/kg taurine were respectively treated to mice for 28 days before weight-loaded swimming test. The results revealed that cordycepin significantly prolonged the weight-loaded swimming time of mice. Meanwhile, cordycepin decreased the levels of lactic acid, blood uric nitrogen, and malondialdehyde, and increased the contents of superoxide dismutase, glutathione, nicotinamide adenine dinucleotide phosphate, hepatic glycogen, muscle glycogen and ATP. The metabolomic study by GC-MS showed that eight biomarkers were found in livers, including L-lactic acid, L-asparagine, 3-phosphoglyceric acid, inosine, D-galactose, L-tyrosine, glyceric acid and L-threonine. There were seven biomarkers in gastrocnemius, including D-ribose-5-phosphate, acetic acid, propionic acid, butyric acid, palmitic acid, oxaloacetic acid and citric acid. The results of metabolomics indicated that cordycepin might relieve fatigue by regulating energy metabolism and pentose phosphate pathway. Furthermore, we found cordycepin significantly enhanced the protein levels of TIGAR, SIRT1, PGC-1α, NRF1 and TFAM in gastrocnemius of weight-loaded swimming mice. Taken together, the present study demonstrated that cordycepin possessed an anti-fatigue effect via activating TIGAR/SIRT1/PGC-1α signaling pathway. Our study indicated that cordycepin may be a potentially efficient candidate for fatigue.