Zhou Tianbiao, Li Hong-Yan, Zhong Hongzhen, Zhong Zhiqing
Department of Nephrology, the Second Affiliated Hospital of Shantou University Medical College, No 69 Dongsha Road, Shantou, 515041, China.
Department of Nephrology, Huadu District People's Hospital of Guangzhou, Southern Medical University, Guangzhou, 510800, China.
BMC Med Genet. 2018 Nov 20;19(1):201. doi: 10.1186/s12881-018-0717-3.
Diabetes mellitus (DM) is divided into four different etiological categories: type 1 DM (T1DM), type 2 DM (T2DM), other specific types, and gestational DM. One severe complication of T2DM is type 2 diabetic nephropathy (T2DN). The possible association of serum transforming growth factor-β1 (TGF-β1) levels and the TGF-β1 T869C gene polymorphism with patient susceptibility to T2DN in Chinese population is unclear at present. This study was conducted to assess these relationships in Chinese population by a meta-analysis.
Association reports were searched and pulled from the Cochrane Library, the China Biological Medicine Database (CBM), and PubMed on March 1, 2018, and eligible studies were selected and used for calculations. The results were expressed as weighted mean differences (MD) for continuous data. Odds ratios (OR) were used to express the results for dichotomous data. Additionally, 95% confidence intervals (CI) were calculated.
Forty-eight reports for the relationship between serum TGF-β1 levels and the risk of T2DN and 13 studies on the association of the TGF-β1 T869C gene polymorphism with susceptibility to T2DN in Chinese population were retrieved from this study. Serum TGF-β1 levels in the T2DM group were higher than those in the normal control group (MD = 17.30, 95% CI: 12.69-21.92, P < 0.00001). The serum TGF-β1 level in the T2DN group was significantly higher than that in the normal control group (MD = 70.03, 95% CI: 60.81-79.26, P < 0.00001;). The serum TGF-β1 level in the T2DN group was significantly higher than that in the T2DM group (MD = 56.18, 95% CI: 46.96-65.39, P < 0.00001). Serum TGF-β1 levels in T2DM patients with microalbuminuria were increased when compared with those in T2DM patients with normoalbuminuria. Furthermore, serum TGF-β1 levels in T2DM patients with macroalbuminuria were increased when compared with those in T2DM patients with microalbuminuria. The TGF-β1 T allele, TT allele and CC genotype were associated with T2DN susceptibility in Chinese population (T: OR = 0.74, 95% CI: 0.59-0.92, P = 0.007; TT: OR = 0.55, 95% CI: 0.31-0.96, P = 0.04; CC: OR = 1.38, 95% CI: 1.14-1.67, P = 0.001).
High levels of TGF-β1 are associated with susceptibility to T2DM, T2DN and the progression of proteinuria in T2DN patients in Chinese population. Further, the TGF-β1 T allele, and TT genotype were protective factors against the onset of T2DN and CC genotype was a risk factor for the susceptibility of T2DN in Chinese populations.
糖尿病（DM）分为四种不同的病因类型：1型糖尿病（T1DM）、2型糖尿病（T2DM）、其他特定类型和妊娠期糖尿病。T2DM的一种严重并发症是2型糖尿病肾病（T2DN）。目前尚不清楚中国人群中血清转化生长因子-β1（TGF-β1）水平和TGF-β1 T869C基因多态性与患者T2DN易感性之间的可能关联。本研究通过荟萃分析评估中国人群中的这些关系。
于2018年3月1日在考克兰图书馆、中国生物医学数据库（CBM）和PubMed中检索并提取关联报告，选择符合条件的研究进行计算。连续数据的结果以加权平均差（MD）表示。比值比（OR）用于表示二分数据的结果。此外，计算95%置信区间（CI）。
本研究检索到48篇关于血清TGF-β1水平与T2DN风险关系的报告，以及13项关于中国人群中TGF-β1 T869C基因多态性与T2DN易感性关联的研究。T2DM组的血清TGF-β1水平高于正常对照组（MD = 17.30，95%CI：12.69 - 21.92，P < 0.00001）。T2DN组的血清TGF-β1水平显著高于正常对照组（MD = 70.03，95%CI：60.81 - 79.26，P < 0.00001）。T2DN组的血清TGF-β1水平显著高于T2DM组（MD = 56.18，95%CI：46.96 - 65.39，P < 0.00001）。与尿白蛋白正常的T2DM患者相比，微量白蛋白尿的T2DM患者血清TGF-β1水平升高。此外，与微量白蛋白尿的T2DM患者相比，大量白蛋白尿的T2DM患者血清TGF-β1水平升高。TGF-β1的T等位基因、TT等位基因和CC基因型与中国人群的T2DN易感性相关（T：OR = 0.74，95%CI：0.59 - 0.92，P = 0.007；TT：OR = 0.55，95%CI：0.31 - 0.96，P = 0.04；CC：OR = 1.38，95%CI：1.14 - 1.67，P = 0.001）。
在中国人群中，高水平的TGF-β1与T2DM、T2DN易感性以及T2DN患者蛋白尿进展相关。此外，TGF-β1的T等位基因和TT基因型是中国人群中T2DN发病的保护因素，CC基因型是T2DN易感性的危险因素。
