scholarly journals Sphk1 involves in the regulation of autophagy process in cardiac myocyte cells at high glucose condition

2019 ◽  
Author(s):  
Wen Ai ◽  
Peiyi Xie ◽  
Li Ling ◽  
Yulan Gao ◽  
Lei Wang ◽  
...  

Abstract Diabetic cardiomyopathy is the myocardium disorders caused by diabetes mellitus, which has become a key concern bringing heavy burden to the public health. Autophagy is one of activities involving in the pathogenesis of diabetic cardiomyopathy. Sphk1 gene plays a crucial role in cell survival and growth, and regulation of many diseases including diabetes and cardiovascular disease. However, the pathogenesis of diabetic cardiomyopathy remains poorly understood. To this aim, the study established adenovirus vectors expressing Sphk1 and shSphk1 to investigate the effects of Sphk1 on autophagy and cell survival in myocardial cells under high glucose conditions (25 mM). It was found that overexpression of Sphk1 promoted autophagy activity in H9c2 cells under high glucose treatment measured by various methodologies including qRT-PCR, western blot, fluorescence microscope, and so on. Inhibition of autophagy decreased cell vitality under high glucose condition. A broadly used medicine silibinin was demonstrated to induce autophagy in a dose-dependent manner. Herein, the findings in the present study may provide useful reference for unveiling the pathogenesis of diabetic cardiomyopathy and developing novel therapies treating diabetic cardiomyopathy.

2018 ◽  
Vol 51 (3) ◽  
pp. 1410-1428 ◽  
Author(s):  
Yajuan Zhang ◽  
Yan Sun ◽  
Rui Peng ◽  
Handeng Liu ◽  
Weihao He ◽  
...  

Background/Aims: Diabetic nephropathy (DN) as the primary cause of end-stage kidney disease is a common complication of diabetes. However, the initiating molecular events triggering DN are unknown. Recently, long noncoding RNAs (lncRNAs) have been shown to play important roles in DN. Methods: The expression level of lncRNA 1500026H17Rik (150Rik for short) was measured by qRT-PCR (quantitative real-time PCR). Cell proliferation ability was detected by 5-Ethynyl-2’-deoxyuridine (EdU). The relationship between 150Rik and microRNA 451 (miR-451) was examined by luciferase assay and RNA immunoprecipitation (RIP) assay. Finally, the effect of 150Rik on cell proliferation through the miR-451/insulin-like growth factor 1 receptor (IGF1R)/mitogen-activated protein kinases (p38MAPK) pathway was detected by EdU, flow cytometry analysis, western blot. Results: We found that 150Rik, an evolutionarily conserved lncRNA, was significantly upregulated in renal tissue of db/db DN mice and in mesangial cells (MCs) cultured under a high glucose condition. Further, overexpression or knockdown of 150Rik was found to regulate cell proliferation in MCs. Moreover, 150Rik was found to interact with miR-451 in both a direct and argonaute-2 (Ago2)-dependent manner. Results also revealed that overexpression of 150Rik inhibited cell proliferation through the miR-451/IGF1R/p38MAPK pathway in MCs under the high glucose condition, while knockdown of 150Rik increased cell proliferation via the miR-451/IGF1R/p38MAPK pathway. Conclusion: Taken together, these results provide new insight into the association between 150Rik and the miR-451/IGF1R/p38MAPK signaling pathway during DN progression.


2017 ◽  
Vol 35 (7) ◽  
pp. 407-413 ◽  
Author(s):  
Elaheh Zafarvahedian ◽  
Azam Roohi ◽  
Mohammad Reza Sepand ◽  
Seyed Nasser Ostad ◽  
Mohammad Hossein Ghahremani

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Miao Chen ◽  
Dian Jing ◽  
Rui Ye ◽  
Jianru Yi ◽  
Zhihe Zhao

Abstract Background Diabetic patients are more vulnerable to skeletal complications. Peroxisome proliferators-activated receptor (PPAR) β/δ has a positive regulatory effect on bone turnover under physiologic glucose concentration; however, the regulatory effect in diabetes mellitus has not been investigated yet. Herein, we explored the effects of PPARβ/δ agonist on the regeneration of diabetic bone defects and the osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) under a pathological high-glucose condition. Methods We detected the effect of PPARβ/δ agonist on osteogenic differentiation of rBMSCs in vitro and investigated the bone healing process in diabetic rats after PPARβ/δ agonist treatment in vivo. RNA sequencing was performed to detect the differentially expressed genes and enriched pathways. Western blot was performed to detect the autophagy-related protein level. Laser confocal microscope (LSCM) and transmission electron microscope (TEM) were used to observe the formation of autophagosomes. Results Our results demonstrated that the activation of PPARβ/δ can improve the osteogenic differentiation of rBMSCs in high-glucose condition and promote the bone regeneration of calvarial defects in diabetic rats, while the inhibition of PPARβ/δ alleviated the osteogenic differentiation of rBMSCs. Mechanistically, the activation of PPARβ/δ up-regulates AMPK phosphorylation, yielding mTOR suppression and resulting in enhanced autophagy activity, which further promotes the osteogenic differentiation of rBMSCs in high-glucose condition. The addition of AMPK inhibitor Compound C or autophagy inhibitor 3-MA inhibited the osteogenesis of rBMSCs in high-glucose condition, suggesting that PPARβ/δ agonist promotes osteogenic differentiation of rBMSCs through AMPK/mTOR-regulated autophagy. Conclusion In conclusion, our study demonstrates the potential role of PPARβ/δ as a molecular target for the treatment of impaired bone quality and delayed bone healing in diabetic patients for the first time.


2021 ◽  
Vol 28 ◽  
Author(s):  
Olga Simó-Servat ◽  
Hugo Ramos ◽  
Patricia Bogdanov ◽  
Marta García-Ramírez ◽  
Jordi Huerta ◽  
...  

Background: Ezrin, radixin, and moesin (the ERM complex) interact directly with membrane proteins regulating their attachment to actin filaments. ERM protein activation modifies cytoskeleton organization and alters the endothelial barrier function, thus favoring vascular leakage. However, little is known regarding the role of ERM proteins in diabetic retinopathy (DR). Objective: This study aimed to examine whether overexpression of the ERM complex exists in db/db mice and its main regulating factors. Methods: 9 male db/db mice and 9 male db/+ aged 14 weeks were analyzed. ERM proteins were assessed by western blot and by immunohistochemistry. Vascular leakage was determined by the Evans blue method. To assess ERM regulation, HRECs were cultured in a medium containing 5.5 mM D-glucose (mimicking physiological conditions) and 25 mM D-glucose (mimicking hyperglycemia that occurs in diabetic patients). Moreover, treatment with TNF-α, IL-1β, or VEGF was added to a high glucose condition. The expression of ERM proteins was quantified by RT-PCR. Cell permeability was evaluated by measuring movements of FITC-dextran. Results: A significant increase of ERM in diabetic mice in comparison with non-diabetic mice was observed. A high glucose condition alone did not have any effect on ERM expression. However, TNF-α and IL-1β induced a significant increase in ERM proteins. Conclusion: The increase of ERM proteins induced by diabetes could be one of the mechanisms involved in vascular leakage and could be considered as a therapeutic target. Moreover, the upregulation of the ERM complex by diabetes is induced by inflammatory mediators rather than by high glucose itself.


1987 ◽  
Vol 19 (07) ◽  
pp. 316-318 ◽  
Author(s):  
N. Watanabe ◽  
M. Kobayashi ◽  
M. Iwasaki ◽  
O. Ishibashi ◽  
Y. Takata ◽  
...  

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