The protective effect of carnosic acid on dextran sulfate sodium-induced colitis based on metabolomics and gut microbiota analysis

Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease(IBD).Carnosic acid(CA)is a major antioxidant component of rosemary and sage.Herein,we investigated the protective effects of dietary CA on dextran sodium sulfate(DSS)-induced colitis mouse model with an emphasis on its impact on the composition and metabolic function of gut microbiota.We found that CA effectively attenuated DSS-stimulated colitis in mice,as evidenced by reduced disease activity index(DAI),and systemic and colonic inflammation.Additionally,CA restored microbial diversity and improved the composition of gut microbiota in DSS-treated mice.Moreover,Spearman’s correlation coefficient showed a significant correlation between the fecal metabolites and the gut microbiota species.Changes in gut microbiota and the correlated metabolites might partially explain CA’s anti-inflammatory effects against colitis.Future clinical trials are needed to determine the therapeutic effects and mechanisms of CA on IBD in humans.

Ancient water wells reveal a prolonged drought in the lower Yellow River area about 2800 years ago

Proxy records from the North Atlantic realm reveal that large and rapid cooling known as the Bond events continued into the Holocene [1],repeatedly punctuating what is conventionally thought to have been a relatively stable climate.Given that the Holocene is the most recent interglacial period that has spurred the development of modern societies,scrutinizing climate variabil- ity during this period is important not only for predicting the trend of future climate changes,but also for better understanding the driving forces behind the rise and fall of ancient civilizations.

Structure analysis of ethyl ferulate from Rubus corchorifolius L.f.leaves and its inhibitory effects on HepG2 liver cancer cells

The tender leaves of Rubus corchorifolius L.f.(R.corchorifolius)have been made into herbal tea for relieving coughs in East and Southeast Asia from ancient times.Herein,we obtained an ethyl acetate extract from R.corchorifolius leaves and isolated a major bioactive compound within.Structural analysis of the isolated compound was performed by spectroscopic methods and the compound was identified as ethyl ferulate.Effect of ethyl ferulate on the growth and proliferation of human liver cancer HepG2 cells and normal human liver LO2 cells was determined by MTT assay.We found that ethyl ferulate significantly suppressed the cell proliferation of HepG2 cells(IC_(50)26.4μM),while it did not cause cytotoxicity on LO2 cells.In addition,flow cytometry analysis demonstrated that ethyl ferulate inhibited HepG2 cell growth via inducing cellular apoptosis.Specifically,ethyl ferulate reduced the electrical potential of the mitochondrial membrane and increased the concentration of calcium ions inside cells.Moreover,these changes were accompanied by increases in the expression of the pro-apoptotic proteins,such as cleaved caspase-3 and Bax.In contrast,cell morphology and growth of LO2 cells remained unaffected.In conclusion,for the first time,our observations demonstrated that ethyl ferulate possesses great potential as an effective and safe antitumor agent for cancer chemoprevention in humans.