Effects and mechanism of Rictor interference in podocyte injury induced by high glucose

Zeng,Yan; Xiong,Changbin; Chen,Yinxiang; Yang,Chunyun; Li,Qiuyue

doi:10.3892/etm.2023.12172

Effects and mechanism of Rictor interference in podocyte injury induced by high glucose

Authors:
- Yan Zeng
- Changbin Xiong
- Yinxiang Chen
- Chunyun Yang
- Qiuyue Li
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Affiliations: Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
Published online on: August 22, 2023 https://doi.org/10.3892/etm.2023.12172
Article Number: 473
Copyright: © Zeng et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Rapamycin‑insensitive companion of mTOR (Rictor) is a critical effector of mTOR protein complex 2 (mTORC2). The aim of the present study was to investigate the effect of Rictor in the mTORC2 signaling pathway in high glucose (HG)‑induced diabetic podocyte injury by silencing the expression of Rictor. In the present study, mouse podocytes were treated with glucose (150 mM) and mannitol (200 mM), the Rictor gene was silenced using small interfering RNA (siRNA). Apoptosis was detected by flow cytometry, whereas podocyte cytoskeletal protein expression was detected by western blotting (WB) and immunofluorescence staining. The results demonstrated that, compared with that in the control group, the podocyte apoptotic rate was significantly increased in the mannitol group (negative group) and the groups that were treated with glucose (model groups). The podocyte apoptotic rate in the model + Rictor siRNA group was significantly decreased compared with that in the negative, model and the model glucose + siRNA negative control (NC) groups. WB indicated that the protein expression levels of podocalyxin and synaptopodin were reduced in the model and model + siRNA NC groups compared with those in the normal control and negative groups. Additionally, the protein expression levels of α‑smooth muscle actin (α‑SMA) and P‑AKT/AKT were increased in the model and model + siRNA NC groups compared with the those in control and negative groups. Compared with those the model and model + siRNA NC groups, the protein expression levels of podocalyxin and synaptopodin were increased, whilst those of the α‑SMA and P‑AKT/AKT proteins were decreased, in the model + Rictor siRNA group. Results from immunofluorescence analysis were basically consistent with those of WB. Therefore, results of the present study suggest that silencing of the Rictor gene may reduce the damage to podocytes induced by HG, such that the Rictor/mTORC2 signaling pathway may be involved in the remodeling of podocyte actin cytoskeletal in diabetes.

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