scholarly journals Bag-1L Protects against Cell Apoptosis in an In Vitro Model of Lung Ischemia-Reperfusion Injury through the C-Terminal “Bag” Domain

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Ji-ling Lv ◽  
Li-na Shi ◽  
Cong-ying Zhai ◽  
Ge-jin Wang ◽  
Yan Qu

Bcl-2-associated athanogene 1 (Bag-1) is a multifunctional and antiapoptotic protein that binds to the antiapoptosis regulator Bcl-2 and promotes cell survival. To investigate the protective function of Bag-1, we examined the effects of Bag-1L, one isoform of Bag-1, in an in vitro cell culture model of lung ischemia-reperfusion injury (LIRI) generated by treatment of A549 cells with hypoxia/reoxygenation. Overexpression of full-length Bag-1L increased the viability of A549 cells and reduced cell apoptosis in response to 6 h of hypoxia/reoxygenation treatment. Furthermore, Bag-1L overexpression enhanced the heat shock protein 70 (HSP70) and Bcl-2 protein levels, increased the phosphorylation of AKT, decreased Bax and cleaved caspase-3 levels, and was able to overcome cell cycle arrest. These effects were not observed in A549 cells overexpressing a truncated form of Bag-1L lacking the “Bag domain,” denoted Bag-1L△C. The “Bag domain” is the C-terminal 47 amino acids. Taken together, the results of this study suggest that Bag-1L overexpression can protect against oxidative stress and apoptosis in an in vitro LIRI model, with a dependence on the Bag domain.

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Chong Huang ◽  
Yan Chen ◽  
Bin Lai ◽  
Yan-Xia Chen ◽  
Cheng-Yun Xu ◽  
...  

Abstract Background Acute kidney injury (AKI) is a major kidney disease with poor clinical outcome. SP1, a well-known transcription factor, plays a critical role in AKI and subsequent kidney repair through the regulation of various cell biologic processes. However, the underlying mechanism of SP1 in these pathological processes remain largely unknown. Methods An in vitro HK-2 cells with anoxia-reoxygenation injury model (In vitro simulated ischemic injury disease) and an in vivo rat renal ischemia-reperfusion injury model were used in this study. The expression levels of SP1, miR-205 and PTEN were detected by RT-qPCR, and the protein expression levels of SP1, p62, PTEN, AKT, p-AKT, LC3II, LC3I and Beclin-1 were assayed by western blot. Cell proliferation was assessed by MTT assay, and the cell apoptosis was detected by flow cytometry. The secretions of IL-6 and TNF-α were detected by ELISA. The targeted relationship between miR-205 and PTEN was confirmed by dual luciferase report assay. The expression and positioning of LC-3 were observed by immunofluorescence staining. TUNEL staining was used to detect cell apoptosis and immunohistochemical analysis was used to evaluate the expression of SP1 in renal tissue after ischemia-reperfusion injury in rats. Results The expression of PTEN was upregulated while SP1 and miR-205 were downregulated in renal ischemia-reperfusion injury. Overexpression of SP1 protected renal tubule cell against injury induced by ischemia-reperfusion via miR-205/PTEN/Akt pathway mediated autophagy. Overexpression of SP1 attenuated renal ischemia-reperfusion injury in rats. Conclusions SP1 overexpression restored autophagy to alleviate acute renal injury induced by ischemia-reperfusion through the miR-205/PTEN/Akt pathway.


2011 ◽  
Vol 165 (2) ◽  
pp. 281-282
Author(s):  
B.J. DuBray ◽  
K.D. Conzen ◽  
G.A. Upadhya ◽  
P. Balachandran ◽  
J. Jia ◽  
...  

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Dongchao Lv ◽  
Shengguang Ding ◽  
Ping Chen ◽  
Yihua Bei ◽  
Chongjun Zhong ◽  
...  

Ischemia-reperfusion injury (IRI) following acute myocardial infarction (AMI) has no effective treatment and a poor prognosis. microRNA (miRNA)-19b is a key functional member of miRNA-19-72 cluster family, regulating cellular proliferation, apoptosis, differentiation, and metabolism. Dysregulation of the miR-19b cluster is critically involved in a spectrum of cardiovascular diseases. However, the role of miR-19b in myocardial IRI is unknown. In this study, we found that miR-19b was downregulated in a mouse model of IRI. Meanwhile, about 50% downregulation of miR-19b was detected in H2O2-treated H9C2 cells mimicking myocardial IRI. We also found that overexpression of miR-19b decreased H2O2-induced apoptosis (36.02%±3.92% vs 29.34%±0.79% in nc-mimics vs miR-19b-mimics, respectively) and necrosis (23.11%±1.64% vs 18.76%±0.71% in nc-mimics vs miR-19b-mimics, respectively), and increased proliferation of H9C2 cells in vitro, while downregulation of miR-19b had reverse effects. Furthermore, PTEN, a previously validated target gene of miR-19b, has been found to be negatively regulated by miR-19b at protein levels in H9C2 cells. These data reveal the potential of miR-19b as a therapeutic target for myocardial IRI.


2020 ◽  
Vol 319 (5) ◽  
pp. F839-F847
Author(s):  
Fanhang Meng ◽  
Yongguang Liu ◽  
Qiuyuan Chen ◽  
Qing Ma ◽  
Shijie Gu ◽  
...  

To investigate the mechanism of renal ischemia-reperfusion injury (IRI) via regulation of N6-methyl-adenosine (m6A) and relevant genes, IRI was induced in Sprague-Dawley rats, and urine and serum creatinine levels and tissue structure changes were observed. m6A and methyltransferase-like 3 (METTL3) protein levels were assessed via dot-blot and Western blot analyses, respectively. The hypoxia/reoxygenation (H/R) cell model was constructed using NRK-52E cells, and METTL3 protein levels were assessed. METTL3 was inhibited to observe its impact on NRK-52E cell apoptosis and m6A expression in H/R processes. Methylated RNA immunoprecipitation (MeRIP) sequencing was conducted followed by MeRIP-quantitative RT-PCR and quantitative RT-PCR validation. Our results indicated that urine and serum creatinine levels increased and that renal injury and cell apoptosis were both observed in the IRI model. In additon, m6A expression increased in the IRI model, and METTL3 protein levels significantly increased in the IRI and H/R models. When METTL3 was inhibited, m6A levels were accordingly decreased and cell apoptosis was suppressed in the H/R in vitro model. Based on MeRIP sequencing, transcription factor activating enhancer binding protein 2α ( tfap2a), cytochrome P-450 1B1 ( cyp1b1), and forkhead box D1 ( foxd1) were significantly differentially expressed, as was m6A, which is involved in the negative regulation of cell proliferation and kidney development. We confirmed that foxd1 mRNA and its methylation levels contributed to IRI and H/R.


2013 ◽  
Vol 218 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Xiaojiong Du ◽  
Sirong He ◽  
Yaowen Jiang ◽  
Lingling Wei ◽  
Weiming Hu

Islets are exceptionally susceptible to ischemia–reperfusion injury, an increased incidence of primary graft nonfunctionality, and β-cell death during a transplant procedure. Therefore, islets require protection during the early stages of the transplant procedure. Based on the beneficial vascular and anti-inflammatory activity of adiponectin, we hypothesize that adiponectin protects islet cells against ischemia–reperfusion injury and graft dysfunction after transplantation. To examine the effects of adiponectin on the resistance of islet ischemia–reperfusion injury, we used the islet hypoxia–reoxygenation injury model and performed kidney subcapsular syngeneic islet transplants to assess the islets' vitality and function. Furthermore, we utilized lipopolysaccharide (LPS)-induced or tumor necrosis factor α (TNFα)-induced damage to islet cells to model the inflammation of post-transplant ischemia–reperfusion injury and transplanted islets in adiponectin knockout mice to explore whether the protective action of adiponectin is involved in TNFα production and nuclear transcription factor-κB (NF-κB) activation. Adiponectin suppressed TNFα production and IκB-α phosphorylation; decreased hypoxia–reoxygenation and LPS-induced and TNFα-induced islet apoptosis; and improved islet function in vivo and in vitro. Our results demonstrate that adiponectin protects the islet from injury. We show that islet protection occurs in response to ischemia–reperfusion and is dependent on the suppression of islet production by TNFα through cyclooxygenase 2 and the inhibition of the TNFα-induced NF-κB activation pathways.


Surgery ◽  
2012 ◽  
Vol 152 (2) ◽  
pp. 247-253
Author(s):  
Bernard J. DuBray ◽  
Kendra D. Conzen ◽  
Gundumi A. Upadhya ◽  
Parvathi Balachandran ◽  
Jianluo Jia ◽  
...  

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