Melatonin protected cardiac microvascular endothelial cells against oxidative stress injury via suppression of IP3R-[Ca2+]c/VDAC-[Ca2+]m axis by activation of MAPK/ERK signaling pathway

Background/Aims: Mitochondrial homeostasis is implicated in the development and progression of endometriosis through poorly defined mechanisms. Mst1 is the major growth suppressor related to cancer migration, apoptosis and proliferation. However, whether Mst1 is involved in endometriosis apoptosis and migration via regulating the mitochondrial function remains to be elucidated. Methods: Expression of Mst1 in endometriosis was examined via western blots. Cellular apoptosis was detected via MTT and TUNEL assay. Gain of function assay about Mst1 was conducted via adenovirus over-expression. Mitochondrial functions were evaluated via mitochondrial membrane potential JC-1 staining, ROS flow cytometry analysis, mPTP opening assessment and immunofluorescence of HtrA2/Omi. The mitophagy activity were examined via western blots and immunofluorescence. Results: First, we found that Mst1 was significantly downregulated in the ectopic endometrium of endometriosis compared to the normal endometrium. However, the recovery of Mst1 function was closely associated with the inability of endometrial stromal cells (ESCs) to migrate and survive. A functional study indicated that regaining Mst1 enhanced Drp1 post-transcriptional phosphorylation at Ser616 and repressed Parkin transcription activity via p53, leading to mitochondrial fission activation and mitophagy inhibition. Excessive Drp1-related fission forced the mitochondria to liberate HtrA2/Omi into the cytoplasm. Moreover, Mst1-induced defective mitophagy evoked cellular

Section: Nr4a Represses Mst1 Expression Via Mir-181cmentioning

confidence: 99%

Section: Cellular Physiology and Biochemistrymentioning

confidence: 99%

Effect of Mst1 on Endometriosis Apoptosis and Migration: Role of Drp1-Related Mitochondrial Fission and Parkin-Required Mitophagy

Zhao

Yang

et al. 2018

“…However, damaged mitochondria liberate the proapoptotic factors, such as cyt-c, into the cytoplasm, thereby initiating caspase-9-related programmed cell death [10]. Numerous studies have identified mitochondria as potential targets to regulate the progression of renal IR injury [11-16]. However, the role of mitophagy in renal I/R injury has not been appropriately investigated.…”

Section: Introductionmentioning

confidence: 99%

Mammalian STE20-Like Kinase 1 Deletion Alleviates Renal Ischaemia-Reperfusion Injury via Modulating Mitophagy and the AMPK-YAP Signalling Pathway

Feng¹,

Li²,

Zhang³

et al. 2018

Background/Aims: The aim of our study is to investigate the molecular mechanism by which mammalian STE20-like kinase 1 (Mst1) participates in renal I/R injury through modifying mitophagy and the AMPK-YAP signalling pathway. Methods: WT mice and Mst1-knockout mice were subjected to renal ischaemia-reperfusion (I/R) in vivo. In vitro, the hypoxia-reoxygenation model was used with renal tubular epithelial cells to mimic renal I/R injury. Mitochondrial function was monitored via western blotting and immunofluorescence. Pathway blocker and siRNA knockout technology were used to establish the role of the AMPK-YAP signalling pathway in Mst1-mediated mitochondrial apoptosis in the setting of renal I/R injury. Results: Our data demonstrated that Mst1 expression was upregulated in response to renal I/R injury in vivo, and a higher Mst1 content was positively associated with renal dysfunction and more tubular epithelial cell apoptosis. However, genetic ablation of Mst1 improved renal function, alleviated reperfusion-mediated tubular epithelial cell apoptosis, and attenuated the vulnerability of kidney to I/R injury. In vitro, Mst1 upregulation induced mitochondrial damage including mitochondrial potential reduction, ROS overloading, cyt-c liberation and caspase-9 apoptotic pathway activation. At the molecular levels, I/R-mediated mitochondrial damage via repressing mitophagy and Mst1 suppressed mitophagy via inactivating AMPK signalling pathway and dowregulating OPA1 expression. Re-activation of AMPK-YAP-OPA1 signalling pathway provided a survival advantage for the tubular epithelial cell in the context of renal I/R injury by repressing mitochondrial fission. Conclusion: Overall, our results demonstrate that the pathogenesis of renal I/R injury is closely associated with an increase in Mst1 expression and the inactive AMPK-YAP-OPA1 signalling pathway. Based on this, strategies to repress Mst1 expression and activate mitophagy could serve as therapeutic targets to treat kidney ischaemia-reperfusion injury.

“…Several studies have shown that melatonin protects against IRI [6,7]. In our previous study, melatonin protected CMECs against oxidative stress injury by activation of the MAPK/ERK signaling pathway [8]. The aim of the present study was to investigate whether melatonin regulates CMEC autophagy through the AMPK/mTOR signaling pathway.…”

Section: Introductionmentioning

confidence: 86%

Melatonin Attenuates Myocardial Ischemia/Reperfusion Injury by Inhibiting Autophagy Via an AMPK/mTOR Signaling Pathway

Chen

Liu

Chen

et al. 2018

Self Cite

Background/Aims: Melatonin has been demonstrated to protect cardiac microvascular endothelial cells (CMECs) against ischemia/reperfusion injury (IRI). Autophagy plays different roles in the heart during ischemia and reperfusion. The AMP activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) pathway is associated with autophagy. This study sought to explore whether melatonin regulates CMEC autophagy through the AMPK/mTOR signaling pathway. Methods: The effects of melatonin in IRI were investigated in vivo rat models and in vitro neonatal CMECs. Myocardial infarct size was achieved by Evans blue and triphenyltetrazolium chloride staining. The severity of cell injury was evaluated by cell vitality and lactate dehydrogenase (LDH) release assays, and autophagy was evaluated by transmission electron microscopy and the assessment of autophagy-related gene expression, such as that of Beclin 1 and light chain 3-II. Results: In vivo, melatonin markedly reduced infarcted area, improved cardiac function and decreased LDH release. However, the AMPK activator AICAR and the mTOR inhibitor rapamycin reduced the protective effects of melatonin on IRI. In vitro, Beclin1 and light chain 3-II protein were found to be down-regulated and autophagosomes were found to be reduced in response to melatonin, together with an increase in cell vitality and a decrease in LDH. Treatment with AICAR or rapamycin ablated the benefit observed with melatonin treatment. Conclusions: Melatonin played an important and protective role in CMECs by inhibiting autophagy against IRI via the AMPK/mTOR system.