Hydrogen sulfide inhibits mitochondrial fission in neuroblastoma N2a cells through the Drp1/ERK1/2 signaling pathway

Abstract

Hydrogen sulfide (H2S) has been demonstrated to have various effects on mitochondrial function. The aim of the present study was to investigate the effects of H2S on mitochondrial fission and the potential underlying mechanisms of these effects. Transmission electron microscopy analysis demonstrated that sodium hydrosulfide (NaHS, a donor of H2S) inhibited mitochondrial fission in a dose‑ and time‑dependent manner. Treating neuro‑2a (N2a) mouse neuroblastoma cells with 400 µM NaHS for 16 h significantly increased the % of elongated mitochondria and reduced the number of mitochondria per cell compared with untreated cells. In addition, the viability and ATP generation of N2a cells that were treated with various concentrations of NaHS was examined. The results demonstrated that treatment with 400 and 600 µM NaHS increased cell viability and ATP generation compared with untreated cells. To further understand the effects of H2S on mitochondrial morphology, the protein and mRNA expression levels of dynamin 1 like (Dnm1l, also known as Drp1) were examined, and the results demonstrated that NaHS dose‑dependently reduced Drp1 mRNA and protein levels, consistent with the mitochondrial morphology changes. To determine whether H2S affects mitochondrial morphology through Drp1 expression, Drp1 was overexpressed in N2a cells using a lentivirus encoding the Drp1 cDNA. It was observed that Drp1 overexpression reversed the effects of NaHS. Furthermore, NaHS promoted the phosphorylation of extracellular signal‑regulated kinase (ERK) 1/2, and the effects of NaHS on Drp1 expression were abolished by an ERK1/2 inhibitor (PD98059). The results of the present study indicate that the H2S‑induced decrease in Drp1 mRNA and protein levels and mitochondrial fission may involve the ERK1/2 signaling pathway. The present study suggests that H2S may be used in the future as a potential therapeutic for diseases that may be mediated by abnormal mitochondria fragmentation, such as Alzheimer's disease.

Opa1 Prevents Apoptosis and Cisplatin-Induced Ototoxicity in Murine Cochleae

“…As shown in Figures 2A,B, we observed elongated and tubular mitochondria in HEI-OC1 cells, then they became highly fragmented upon the loss of Opa1. In Neuro 2a cells, in contrast, fragmented mitochondria were observed by MitoTracker staining even in untreated control cells (data not shown), which is consistent with a previous report that only 30% of mitochondria in this cell line had a length at least twice their width when observed by transmission electron microscopy (Qiao et al, 2017). Because of this, we were unable to observe a change in mitochondrial shape following Opa1 knockdown in Neuro 2a cells, as assessed by MitoTracker staining.…”

DNMT1 maintains metabolic fitness of adipocytes through acting as an epigenetic safeguard of mitochondrial dynamics

“…While changes in mitochondrial fission are likely mediated by the coordinated interplay among complex signaling cascades modulating transcription, protein stability, and translocation of Drp1, a majority of Drp1 studies have focused on posttranslational modifications (e.g., phosphorylation, S-nitrosylation, and SUMOylation) that affect protein stability and the interaction with factors that facilitate translocation. However, relatively few studies to date have addressed the regulatory pathways that modulate the transcription of Dnm1l in physiological and pathophysiologic states (36,37). Here, we showed that Dnmt1-dependent DNA methylation is crucial for sustaining physiological level of Dnm1l expression in adipocytes.…”

Changes in the Structural Characteristics of Platelets and Leukocytes in Patients With Arterial Hypertension Under the Influence of a Hydrogen Sulfide Donor

“…At present there are few data on the influence of H 2 S the total number of MC in cells. However, it is believed that H 2 S exerts different effects on the number, function, and dynamics of MC depending on the used dose [29]. Probably the presumed concentration is effective for increasing the number of organelles.…”