Phoenixin 20 promotes neuronal mitochondrial biogenesis via CREB-PGC-1 alpha pathway
JOURNAL OF MOLECULAR HISTOLOGY
Authors: Yang, Yanwen; Lv, Yinglian; Liu, Junpeng; Zhang, Shuyun; Li, Yun; Shi, Yong
Abstract
Neurodegenerative disorders are dreadful diseases that affect millions of people worldwide. Mitochondrial dysfunction is closely associated with the development of neurodegenerative disorders. Phoenixin 20 is a newly discovered neuropeptide with a pleiotropic effect. This study showed that the presence of Phoenixin 20 promoted neuronal mitochondrial biogenesis in vitro. In cultured neuronal M17 cells, Phoenixin 20 increased the expression of mitochondrial regulators PGC-1 alpha, NRF-1, and TFAM at both mRNA and protein levels. The treatment of Phoenixin 20 increased the ratio of mitochondrial vs nuclear DNA (mtDNA/nDNA) and the multiple mitochondrial gene expression as revealed by increasing mRNA expression of Tomm22, Timm50, Atp5d, Ndufs3, and protein expression of NDUFB8. At a cellular level, Phoenixin 20 promoted mitochondrial respiratory rate and cellular ATP production. Mechanistically, we found that Phoenixin 20 induced the phosphorylation of CREB, which suggests that Phoenixin 20 promoted the activation of the CREB pathway. The blockage of CREB by its selective inhibitor H89 prevented the effect of Phoenixin 20 on mitochondrial regulators and biogenesis. Moreover, the study showed that Phoenixin 20 induced the expression of its tentative receptor GPR173 at the mRNA and protein level, and the silence of GPR173 in neuronal cells ablated all its effect on mitochondrial regulation. Collectively, we showed that Phoenixin 20 promoted neuronal mitochondrial biogenesis via the regulation of CREB-PGC-1 alpha pathway. This study revealed a new role and underlying mechanism of Phoenixin 20 in neuronal cells, suggesting it influences the therapeutic implication of neurodegenerative diseases.
Selenium deficiency inhibits myocardial development and differentiation by targeting the mir-215-5p/CTCF axis in chicken
METALLOMICS
Authors: Cai, Jingzeng; Yang, Jie; Liu, Qi; Gong, Yafan; Zhang, Yuan; Zhang, Ziwei
Abstract
Selenium (Se) is imperative for normal myocardial differentiation and development, and these basic cellular functions can be regulated by miRNA during cardiogenesis. Here, we show that Se deficiency can cause defects in myocardial development and abnormalities of cardiomyocyte differentiation. In previous work using microRNAome analysis, we found that miR-215-5p was differentially expressed in Se-deficient myocardial tissues. However, the relationship between miR-215-5p and Se deficiency in myocardial development remains unknown. In this study, CCCTC-binding factor (CTCF) was confirmed as the target gene of miR-215-5p by dual luciferase reporter assay, western blot and quantitative realtime polymerase chain reaction (qRT-PCR) in cardiomyocytes. Based on in vivo and in vitro results, we found that the increased expression of miR-215-5p induced by Se deficiency may cause transcriptional disorders of myocardial genes, mitochondrial biosynthesis imbalance, and a reduction of myocardial development and differentiation-related factors. Moreover, miR-215-5p may target CTCF to regulate myocardial development and differentiation via the noncanonical Wnt signaling pathway and induce mitochondrial dysfunction via the PGC-1 alpha-TFAM-NRF1/2 pathway in the heart. Our results not only demonstrated that Se deficiency affected myocardial development and differentiation by directly targeting the miR-215-5p/CTCF axis but also found that miR-215-5p inhibitor promoted normal differentiation of cardiomyocytes and myocardial development and ameliorated myocardium structural abnormalities via the noncanonical Wnt signaling pathway in chicken. Our findings support the potential of applying miRNAs during the process of cardiogenesis and indicate that miR-215-5p could be a novel candidate for treatment of cardiac hypoevolutism.