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Ulcerative colitis (UC) is a major form of inflammatory bowel disease (IBD) with high incidence and prevalence in many countries. Patients with UC usually suffer from a lifetime of debilitating physical symptoms. Therefore, developing effective therapeutic strategy that can manage this disease better and improve patients’ life quality is in urgent need. Sesamin (SSM) is a lignan derived from sesame seeds. In this study, the protective effect of SSM against UC and the underlying mechanism were investigated in vitro and in vivo. Our data showed that SSM protected Caco-2 cells from H2O2-induced oxidative stress injury via GSH-mediated scavenging of reactive oxygen species (ROS). Dual luciferase reporter assay showed that the transcriptional activity of nuclear factor erythroid-related factor 2 (Nrf2) was significantly increased by SSM, and the ability of SSM to activate Nrf2-targeted genes was further confirmed in Caco-2 cells using western blot and quantitative real-time PCR (qRT-PCR). In contrast, Nrf2 knockdown abolished the protective effect of SSM. Additionally, we found that SSM also activated advanced protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) in Caco-2 cells, while either AKT or ERK inhibition can prevent SSM-mediated nuclear translocation of Nrf2. Furthermore, SSM displayed a better protective effect against dextran sulfate sodium- (DSS-) induced UC compared with 5-aminosalicylic acid (5-ASA) in C57BL/6 mice. The enhanced Nrf2 signaling and activated AKT/ERK were also observed in the colon of mice after SSM administration. These results first demonstrate the protective effect of SSM against UC and indicate that the effect is associated with AKT/ERK activation and subsequent Nrf2 signaling enhancement. This study provides a new insight into the medicinal value of SSM and proposes it as a new natural nutrition for better managing the symptoms of UC.

A growing body of evidence indicates that marine sponge-derived microbes possess the potential ability to make prolific natural products with therapeutic effects. This review for the first time provides a comprehensive overview of new cytotoxic agents from these marine microbes over the last 62 years from 1955 to 2016, which are assorted into seven types: terpenes, alkaloids, peptides, aromatics, lactones, steroids, and miscellaneous compounds.

The pentose phosphate pathway (PPP), which branches from glycolysis, is correlated with cancer cell proliferation, survival and senescence. In this study, differences in the metabolic profile of the PPP and the redox status of human lung carcinoma A549 cells and cisplatin-induced multidrug-resistant A549/DDP cells were analyzed and evaluated. The results showed that A549/DDP cells exhibited differential PPP-derived metabolic features and redox-related molecules. A549/DDP cells exhibited increased expression and enzymatic activity of PPP enzyme glucose-6-phosphate dehydrogenase (G6PD). Furthermore, as demonstrated by the apoptotic rate, cell viability, and colony formation, inhibition of G6PD by siRNA or an inhibitor sensitized A549/DDP cells to cisplatin. Additionally, inhibition of G6PD restored the cisplatin sensitivity of A549/DDP cells by influencing redox homeostasis. In conclusion, overcoming cisplatin resistance through inhibition of G6PD could improve the understanding of the mechanisms underlying cisplatin-induced resistance in human lung cancer and may provide insights into the therapeutic potential of this treatment to combat resistance.

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