Nephroprotective Role of Zhibai Dihuang Wan in Aristolochic Acid-Intoxicated Zebrafish.

Zhibai Dihuang Wan (ZDW) is an eight-herbal formula of traditional Chinese medicine. Clinically, it regulated immune activity and was used to treat diabetes and renal disease. In this study, we aimed to explore the nephroprotective effect of ZDW in an aristolochic acid- (AA-) intoxicated zebrafish model. We used a green fluorescent kidney transgenic zebrafish to evaluate the nephroprotective effects of ZDW by recording subtle changes in the kidney. Our results demonstrated that ZDW treatment can attenuate AA-induced kidney malformations (60% for AA-treated, 47% for pretreatment with ZDW, and 17% for cotreatment ZDW with AA, n = 50). Furthermore, we found that the expression levels of tnfα and mpo were decreased either in pretreatment or cotreatment groups. In conclusion, our findings revealed that AA-induced nephrotoxicities can be attenuated by ZDW. Therefore, we believe that zebrafish represent an efficient model for screening AA-protective Chinese medicine.

Klotho Exerts an Emerging Role in Cytokinesis.

The Klotho gene functions as an anti-aging gene. A previous klotho-knockout mice study indicated that neither male nor female gametocytes could accomplish the first meiotic division. It suggested that Klotho might regulate cell division. In this study, we determined the roles of Klotho in cytokinesis in cultural human cells (HEK293 and HeLa) and in zebrafish embryos. Immunoprecipitation, mass spectrometry analysis, and a zebrafish model were used in this study. The results showed that Klotho is located in the midbody, which correlated with cytokinesis related kinases, Aurora kinase B and citron kinases, in the late stage of cytokinesis. There was a spatial correlation between the abscission site and the location of Klotho in the cytokinesis bridge. A three-dimensional structural reconstruction study demonstrated there was a spatial correlation among Klotho, Aurora kinase B, and citron kinases in the midbody. In addition, Klotho depletion inactivated Aurora kinases; it was also indicated that Klotho depletion caused aberrant cell cycle and delayed cytokinesis in a cell model. The study with zebrafish embryos suggested that klotho knockdown caused early embryo development abnormality due to dysregulated cytokinesis. In conclusion, Klotho might have a critical role in cytokinesis regulation by interacting with the cytokinesis related kinases.