Yuliang Xu,Xiaozhou Wang,Na Geng,Yiran Zhu,Shuo Zhang,Yongxia Liu,Jianzhu Liu
Cr (VI), which is a common heavy metal pollutant with strong oxidizing property, exists widely in nature. Organisms can be exposed to Cr (VI) through various means. Cr (VI) causes mitochondrial dysfunction after being absorbed by cells. Whether Cr (VI) induces the selective autophagic degradation of mitochondria, which is a biological process called mitophagy, remains unclear. Mitophagy not only recycles intracellularly damaged mitochondria to compensate for nutrient deprivation but also is involved in mitochondria quality control. Thus, this study investigated whether Cr (VI) could induce mitophagy in DF-1 cells. Carbonyl cyanide m-chlorophenylhydrazone, which is a mitochondrial-uncoupling reagent that induces mitophagy, was used. DF-1 cells were incubated with different doses of Cr (VI) for varying durations. The autophagy-related proteins LC3-II and p62 levels decreased after 6 h of Cr (VI) treatment but recovered within 24 h. The mitochondrial membrane potential, which is an indicator of mitochondrial damage, was detected by flow cytometry. We found that different durations of Cr (VI) treatment induced mitochondrial mass decrease and depolarization. Furthermore, the expression of the protein translocase of outer mitochondrial membrane 20 (TOMM20), which is a mitochondrial outer membrane protein, was decreased significantly in the presence of Cr (VI). Our findings indicate that Cr (VI) may contribute to the mitochondrial morphology and function damage and may therefore lead to the autophagic clearance of mitochondria.
Tianxiao Yang,Pingping Zhou,Ziwei Zhang,Xinyu Hao,Shaowei Liu,Haoyu Chen,Yuhua Wang,Yangang Wang
This research aims to explore the therapeutic effect and potential mechanisms of Huazhuojiedu decoction (HZJD) for alleviating precancerous lesions of gastric cancer (PLGC) both in vivo and in vitro. HZJD is a traditional Chinese herbal formula consisting of 11 herbs. Sprague-Dawley (SD) rats were randomly divided into four subgroups: control group, model group, positive drug group, and HZJD group. Hematoxylin-eosin (H&E) staining, high iron diamine-alcian blue (HID-AB) staining, alcian blue-periodic acid Schiff (AB-PAS) staining, immunohistochemistry, immunofluorescence, RT-qPCR, and Western blot assays were performed after 10 weeks of HZJD treatment. In vitro, the cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to detect cell proliferation. RT-qPCR and Western blot assays were performed to evaluate mitophagy levels. The results indicated that HZJD could retard the pathological progression in PLGC rats and reduce PLGC cell proliferation. Treatment with HZJD significantly increased the mRNA and protein expression levels of Sirt3, Foxo3a, Parkin, and LC3 II/I, while decreasing the mRNA and protein expression levels of p62 and Tomm20. HZJD was found to have the ability to reverse the decline in mitophagy activity both in vivo and in vitro. In conclusion, the study assessed the impact of HZJD and provided evidence regarding its potential molecular mechanism.