Protocatechuic acid (PCA) is a natural component with multiple biological activities. However, the underlying mechanisms of the effects of PCA on anti-ulcerative colitis (UC) are unclear. A UC mouse model was established by allowing the mice to freely drink a dextran sulfate sodium solution. The mice were administered PCA intragastrically for 7 days. Histological pathology, intestinal flora, and ferroptosis regulators were determined in vivo. Additionally, ferroptotic Caco-2 cells were modeled to investigate the role of PCA in ferroptosis. Our results showed that PCA reduced the levels of the disease activity index, inflammatory factors, and histological damage in UC mice. We also found that the regulation of intestinal flora, especially Bacteroidetes, was one of the potential mechanisms underlying the protective effects of PCA anti-UC. Moreover, PCA downregulated the level of ferroptosis in the colon tissue, as evidenced by a reduced iron overload, decreased glutathione depletion, and a lower level of malondialdehyde production compared with the model group. Similar effects of PCA on ferroptosis were observed in Erastin-treated Caco-2 cells. The results obtained using reactive oxygen species assays and the changes in mitochondrial structure observed via scanning electron microscopy also support these results. Our findings suggested that PCA protected against UC by regulating intestinal flora and ferroptosis.

Objectives Shaoyao Gancao Decoction (SGD) is a well-known Chinese herbal prescription used to treat ulcerative colitis (UC). This study was designed to evaluate the effect of SGD in dextran sulfate sodium-induced UC and to reveal the potential mechanism. Methods A UC mouse model was established by the administration of dextran sulfate sodium. The mice were given SGD extract intragastrically for 7 days. Histological pathology, inflammatory factors, and ferroptosis regulators were determined in vivo. In addition, ferroptotic Caco-2 cells were prepared to investigate the underlying mechanism of the effects of SGD. Key findings The results showed that SGD reduced the disease activity index, the level of inflammatory factors, and histological damage in mice with UC. Moreover, SGD down-regulated the level of ferroptosis in cells in colon tissue, as evidenced by a reduced iron overload, decreased glutathione depletion, and a lower level of malondialdehyde production, compared with the model group. Correspondingly, similar effects of SGD on ferroptosis were observed in Erastin-treated Caco-2 cells. The results of our in vitro reactive oxygen species assays and the changes in mitochondrial structure observed by scanning electron microscopy also supported these results. Conclusion Taken together, these findings suggest that SGD protected against UC by down-regulating ferroptosis in colonic tissue.

Abnormal ovarian function is the main manifestation of female reproductive toxicity. Granulosa cells (GCs) play an important role in determining the fate of follicles and are the main effector cells of the female reproductive system. Excessive apoptosis of GCs leads to pathological folliculogenesis and further reproductive damage. However, drugs available for treatment of female reproductive toxicity are limited. Recent studies have confirmed that various natural products and bioactive ingredients of traditional Chinese medicine (TCM) can inhibit apoptosis of GCs and protect ovarian function. In this review, the mechanisms underlying the proapoptotic and antiapoptotic effects of natural products and bioactive ingredients of TCM on the proliferation, function, and apoptosis of GCs are summarized based on the findings of reports published over the past 10 years as reference for the treatment of female reproductive toxicity.