Intermittent hypoxia causes histological kidney damage and increases growth factor expression in a mouse model of obstructive sleep apnea.
Intermittent hypoxia causes histological kidney damage and increases growth factor expression in a mouse model of obstructive sleep apnea.
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DOI：
10.1371/journal.pone.0192084
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发表时间：
2018
期刊：
影响因子：
3.7
通讯作者：
Laher I
中科院分区：
文献类型：
--
作者：
Abuyassin B;Badran M;Ayas NT;Laher I
流行病学研究表明阻塞性睡眠呼吸暂停（OSA）与肾功能加速丧失之间存在关联。目前还不清楚功能下降是由于OSA本身还是其他混杂因素如肥胖。此外，与OSA相关的肾脏结构异常尚不清楚。本研究的目的是确定是否间歇性缺氧（IH），OSA的一个关键的病理特征，诱导肾组织病理学损伤使用小鼠模型。将10只8周龄的野生型雄性CB 57 BL/6小鼠随机分配接受IH或间歇性空气（IA）60天。人道处死后，对每只动物的一个肾脏进行多聚甲醛去固定，然后切片进行组织病理学和免疫组织化学分析。在高碘酸-希夫染色的肾切片中测量肾小球肥大和系膜基质扩张，同时通过免疫组织化学半定量肾小球转化生长因子-β1（TGF-β1）、结缔组织生长因子（CTGF）和血管内皮生长因子-A（VEGF-A）蛋白。用3，3 ′-二氨基联苯胺显色剂检测抗原抗体反应，以显色强度半定量肾小球蛋白表达。为了提高蛋白质半定量的准确性，仅使用高阳性染色的百分比进行分析。通过蛋白质印迹法进一步定量肾皮质中TGF-β、CTGF和VEGF-A蛋白的水平。细胞凋亡也进行了研究，通过测量皮质抗凋亡B细胞淋巴瘤2（Bcl-2）和凋亡Bcl-2相关的X（Bax）蛋白的蛋白质免疫印迹。用荧光末端脱氧核苷酸转移酶（TdT）dUTP缺口末端标记（TUNEL）染色进一步研究细胞凋亡。最后，测定血清肌酐和24小时尿白蛋白水平作为肾功能的一般指标。我们的结果表明，暴露于IH的小鼠具有增加的肾小球面积（1.13倍，p< 0.001）和系膜基质的扩张（1.8倍，p< 0.01）。此外，TGF-β1、CTGF和VEGF-A蛋白的表达在IH暴露的小鼠中分别高2.7、2.2和3.8倍（均p< 0.05）。此外，蛋白质印迹分析表明，IH暴露的小鼠表达更高水平的TGF-β1，CTGF和VEGF-A蛋白，分别为1.9，4.0和1.6倍（p< 0.05）。肾细胞凋亡在IH组中更大，如通过增加的皮质Bax/Bcl-2蛋白比率（p< 0.01）和更高的荧光TUNEL染色（p< 0.001）所示。最后，暴露于IH的小鼠的24小时尿白蛋白水平更高（43.4 μg vs 9.7 μg，p< 0.01），而两组之间的血清肌酐水平没有差异。我们的结论是，IH导致肾损伤，伴随着肾小球肥大，系膜基质扩张，肾小球生长因子的表达增加和细胞凋亡增加。
Epidemiological studies demonstrate an association between obstructive sleep apnea (OSA) and accelerated loss of kidney function. It is unclear whether the decline in function is due to OSA per se or to other confounding factors such as obesity. In addition, the structural kidney abnormalities associated with OSA are unclear. The objective of this study was to determine whether intermittent hypoxia (IH), a key pathological feature of OSA, induces renal histopathological damage using a mouse model. Ten 8-week old wild-type male CB57BL/6 mice were randomly assigned to receive either IH or intermittent air (IA) for 60 days. After euthanasia, one kidney per animal was paraformaldehyde-fixed and then sectioned for histopathological and immunohistochemical analysis. Measurements of glomerular hypertrophy and mesangial matrix expansion were made in periodic acid–Schiff stained kidney sections, while glomerular transforming growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF) and vascular endothelial growth factor-A (VEGF-A) proteins were semi-quantified by immunohistochemistry. The antigen-antibody reaction was detected by 3,3′-diaminobenzidine chromogen where the color intensity semi-quantified glomerular protein expression. To enhance the accuracy of protein semi-quantification, the percentage of only highly-positive staining was used for analysis. Levels of TGF-β, CTGF and VEGF-A proteins in the kidney cortex were further quantified by western blotting. Cellular apoptosis was also investigated by measuring cortical antiapoptotic B-cell lymphoma 2 (Bcl-2) and apoptotic Bcl-2-associated X (Bax) proteins by western blotting. Further investigation of cellular apoptosis was carried out by fluorometric terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining. Finally, the levels of serum creatinine and 24-hour urinary albumin were measured as a general index of renal function. Our results indicate that mice exposed to IH have an increased glomerular area (by 1.13 fold, p< 0.001) and expansion of mesangial matrix (by 1.8 fold, p< 0.01). Moreover, the glomerular expressions of TGF-β1, CTGF and VEGF-A proteins were 2.7, 2.2 and 3.8-fold higher in mice exposed to IH (p< 0.05 for all). Furthermore, western blotting protein analysis demonstrates that IH-exposed mice express higher levels of TGF-β1, CTGF and VEGF-A proteins by 1.9, 4.0 and 1.6-fold (p< 0.05 for all) respectively. Renal cellular apoptosis was greater in the IH group as shown by an increased cortical Bax/Bcl-2 protein ratio (p< 0.01) and higher fluorometric TUNEL staining (p< 0.001). Finally, 24-hr urinary albumin levels were higher in mice exposed to IH (43.4 μg vs 9.7 μg, p< 0.01), while there were no differences in serum creatinine levels between the two groups. We conclude that IH causes kidney injury that is accompanied by glomerular hypertrophy, mesangial matrix expansion, increased expression of glomerular growth factors and an increased cellular apoptosis.
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DOI：
10.1093/ndt/gft480
发表时间：
2014-07
期刊：
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association
影响因子：
--
作者：
Hughson MD;Puelles VG;Hoy WE;Douglas-Denton RN;Mott SA;Bertram JF
通讯作者：
Bertram JF
影响因子：
15.9
作者：
Daehn, Ilse;Casalena, Gabriella;Bottinger, Erwin P.
通讯作者：
Bottinger, Erwin P.
DOI：
10.1161/hypertensionaha.113.01425
发表时间：
2013-11
期刊：
Hypertension (Dallas, Tex. : 1979)
影响因子：
--
作者：
Friederich-Persson M;Thörn E;Hansell P;Nangaku M;Levin M;Palm F
通讯作者：
Palm F
影响因子：
19.6
作者：
Fogo, AB
通讯作者：
Fogo, AB
影响因子：
6.1
作者：
Chou, Yu-Ting;Lee, Pei-Hsien;Chen, Ning-Hung
通讯作者：
Chen, Ning-Hung