TXNIP regulates mitophagy in retinal Müller cells under high-glucose conditions: implications for diabetic retinopathy.
TXNIP regulates mitophagy in retinal Müller cells under high-glucose conditions: implications for diabetic retinopathy.
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DOI：
10.1038/cddis.2017.190
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发表时间：
2017-05-11
影响因子：
9
通讯作者：
Singh LP
中科院分区：
文献类型：
--
作者：
Devi TS;Somayajulu M;Kowluru RA;Singh LP
硫氧还蛋白相互作用蛋白（TXNIP）参与糖尿病视网膜病变的氧化应激和细胞凋亡。然而，TXNIP在通过线粒体自噬（macroautophagy）去除受损线粒体（MT）中的作用仍有待研究。在这里，我们调查相关的细胞和分子机制的线粒体自噬在视网膜细胞糖尿病条件下。为此，我们在高糖（25 mM，HG）或低糖（5.5 mM，LG）条件下维持大鼠Müller细胞系（rMC 1）5天。我们的数据表明，HG上调TXNIP在胞质溶胶以及在MT。此外，线粒体氧化应激和膜去极化在长时间高血糖下发生，导致片段化。这些受损的MT被靶向溶酶体进行线粒体吞噬降解，这通过线粒体蛋白COXIV（细胞色素c氧化酶的亚基）与自噬体标记物LC 3BII和溶酶体膜蛋白LAMP 2A的共定位是明显的。此外，在HG条件下，有一个积累的动力蛋白相关的裂变蛋白Drp 1和E3泛素连接酶帕金在受损的MT，这表明它们的作用，在线粒体片段化和泛素化，分别是在LG条件下不存在。随后，泛素受体，视神经磷酸酶和p62/sequestrome 1，结合到受损的MT，并将它们靶向LC 3BII自噬体。相反，通过CRISPR/Cas9和TXNIP gRNA敲除TXNIP可防止rMC 1中HG诱导的线粒体损伤和线粒体自噬。最后，TXNIP水平在体内糖尿病大鼠视网膜中也显着上调，并诱导放射状胶质纤维酸性蛋白表达（Müller胶质细胞活化的标志物）和LC 3BII斑点的形成，这些都可以通过玻璃体内注射TXNIP siRNA来预防。因此，TXNIP是预防糖尿病眼部并发症的潜在靶点。
Thioredoxin-interacting protein (TXNIP) is involved in oxidative stress and apoptosis in diabetic retinopathy. However, the role of TXNIP in the removal of damaged mitochondria (MT) via mitophagy, a process of macroautophagy, remains unexplored. Here we investigate the associated cellular and molecular mechanisms underlying mitophagy in retinal cells under diabetic conditions. For this, we maintained a rat Müller cell line (rMC1) under high-glucose (25 mM, HG) or low-glucose (5.5 mM, LG) condition for 5 days. Our data reveal that HG upregulates TXNIP in the cytosol as well as in the MT. Moreover, mitochondrial oxidative stress and membrane depolarization occur under prolonged hyperglycemia leading to fragmentation. These damaged MT are targeted to lysosome for mitophagic degradation, as is evident by co-localization of mitochondrial protein COXIV, a subunit of cytochrome c oxidase, with autophagosome marker LC3BII and the lysosomal membrane protein LAMP2A. In addition, under HG conditions, there is an accumulation of dynamin-related fission protein Drp1 and E3 ubiquitin ligase Parkin in damaged MT, suggesting their roles in mitochondrial fragmentation and ubiquitination, respectively, which is absent in LG conditions. Subsequently, ubiquitin receptors, optineurin and p62/sequestrome 1, bind to the damaged MT and target them to LC3BII autophagosomes. Conversely, TXNIP knockout via CRISPR/Cas9 and TXNIP gRNA prevents the HG-induced mitochondrial damage and mitophagy in rMC1. Last, TXNIP level is also significantly upregulated in the diabetic rat retina in vivo and induces radial glial fibrillary acidic protein expression, a marker for Müller glia activation, and the formation of LC3BII puncta, which are prevented by intravitreal injection of TXNIP siRNA. Therefore, TXNIP represents a potential target for preventing ocular complications of diabetes.
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影响因子：
64.8
作者：
Diao, Jiajie;Liu, Rong;Rong, Yueguang;Zhao, Minglei;Zhang, Jing;Lai, Ying;Zhou, Qiangjun;Wilz, Livia M.;Li, Jianxu;Vivona, Sandro;Pfuetzner, Richard A.;Brunger, Axel T.;Zhong, Qing
通讯作者：
Zhong, Qing
影响因子：
16
作者：
Pan JA;Sun Y;Jiang YP;Bott AJ;Jaber N;Dou Z;Yang B;Chen JS;Catanzaro JM;Du C;Ding WX;Diaz-Meco MT;Moscat J;Ozato K;Lin RZ;Zong WX
通讯作者：
Zong WX
影响因子：
5.6
作者：
Perrone, Lorena;Devi, Takhellambam S.;Singh, Lalit P.
通讯作者：
Singh, Lalit P.
DOI：
10.1038/mt.2015.220
发表时间：
2016-03
期刊：
Molecular therapy : the journal of the American Society of Gene Therapy
影响因子：
--
作者：
Bakondi B;Lv W;Lu B;Jones MK;Tsai Y;Kim KJ;Levy R;Akhtar AA;Breunig JJ;Svendsen CN;Wang S
通讯作者：
Wang S
影响因子：
4.8
作者：
Saxena, Geetu;Chen, Junqin;Shalev, Anath
通讯作者：
Shalev, Anath