Co-exposure to pentachlorophenol (PCP) and cadmium (Cd) triggers apoptosis-like cell death in Eschericia coli.

Pentachlorophenol (PCP) - cadmium (Cd) complex pollution has been identified as a form of persistent soil pollution in south China, exerting detrimental impacts on the indigenous soil bacterial communities. Hence, it is worthwhile to investigate whether and how bacterial populations alter in response to these pollutants. In this study, Escherichia coli was used as a model bacterium. Results showed that PCP exposure caused bacterial cell membrane permeability changes, intracellular ROS elevation, and DNA fragmentation, and triggered apoptosis-like cell death at low exposure concentration and necrosis at high exposure concentration. Cd exposure caused severe oxidative damage and cell necrosis in the tested bacterial strain. The co-exposure to PCP and Cd elevated the ROS level, stimulated the bacterial caspase activity, and induced DNA fragmentation, thereby leading to an apoptosis-like cell death. In conclusion, PCP-Cd complex pollution can cause bacterial population to decrease through apoptosis-like cell death pathway. However, it is worth noting that the subpopulation survives under the complex pollution stress.

Glucan from Oudemansiella raphanipes suppresses breast cancer proliferation and metastasis by regulating macrophage polarization and the WNT/ß-catenin signaling pathway.

Background: The glucan extract of Oudemansiella raphanipes (Orp) has multiple biological properties, similar to extracts of other natural edible fungi. Drugs traditionally used in cancer treatment are associated with several drawbacks, such as side effects, induction of resistance, and poor prognosis, and many recent studies have focused on polysaccharides extracted from natural sources as alternatives. Our study focuses on the therapeutic role and molecular mechanism of action of Orp in breast cancer progression. Methods: MMTV-PyMT transgenic mice were used as the spontaneous breast cancer mice model. Immunoblotting, hematoxylin-eosin staining, immunohistochemistry, and immunofluorescence were used to evaluate the tumor behaviors in breast cancer. The inflammatory cell model was constructed using TNF-α. Macrophage activation and WNT/ß-catenin signaling were assayed using western blotting and immunofluorescence. Results: Orp management significantly inhibited tumor growth and promoted tumor cell apoptosis in MMTV-PyMT transgenic mice. Besides, the Orp challenge also attenuated the ability of breast tumors to metastasize into lung tissues. Mechanistically, Orp treatment restrained the polarization of M1 macrophages to M2 macrophages and suppressed WNT/ß-catenin signaling in mouse tumor tissues, which implied that Orp-mediated tumor inhibition partly occurred via regulating the inflammatory response. Findings from in vitro experiments confirmed that Orp inhibited the TNF-α-induced nuclear transportation of ß-catenin, thus preventing inflammation signaling and the expression of c-Myc in MCF-7 cells. Conclusion: Orp inhibits breast cancer growth and metastasis by regulating macrophage polarization and the WNT/ß-catenin signaling axis. The findings of this study suggest that Orp may be a promising therapeutic strategy for breast cancer.