The Effect of Chinese Medicinal Formulas on Biomarkers of Oxidative Stress in STZ-Induced Diabetic Kidney Disease Rats: A Meta-Analysis and Systematic Review

BACKGROUND: Diabetic kidney disease (DKD), defined broadly as persistent proteinuria with low estimated glomerular filtration rate in patients with diabetes, is a main cause of end-stage renal disease. Excessive production of reactive oxygen species is an important mechanism underlying the pathogenesis of DKD and many antioxidants have been investigated as therapeutic agents. Among them, Chinese medicine antioxidative stress therapies have been widely used to combat DKD, which may offer new insights into therapeutic development of DKD. There are several discrepancies among the efficacy of Western medicine (WM) and Chinese medicinal formula (CMF) action. METHODS: We searched PubMed, Cochrane Library, the Web of Science databases, Embase, and Scopus from inception to December 2021 using relevant keywords and a comprehensive search for randomized controlled trials (RCTs) was performed. Calculating the pooled weighted mean difference (MD) and 95% CI by the method of inverse-variance with a random-effect. All the related statistical analyses were performed using Stata version 15.1 software (Stata Corporation) and Rvman version 5.3 (Nordic Cochrane Center). RESULTS: A total of 8 articles with the 9 groups including 106 in the model group, 105 in the CMF group, and 99 in the WM group. Pooled data from 8 studies (9 groups) showed a statistical improvement in superoxide dismutase compared with the model group [standardized MD (SMD) = 1.57; 95 CI: 1.16–1.98; P < 0.05] and the WM group (SMD = 0.56; 95 CI: 0.19–0.92; P < 0.05). For glutathione peroxidase (GSH-Px), it was significantly improved in the CMF group vs. the model group and the WM group. For malondialdehyde (MDA), it was significantly reduced in the CMF group (CMF vs. model group: SMD = −1.52; 95 CI: −1.88 −1.17; P < 0.05; CMF vs. WM group: SMD = −0.64; 95 CI: −0.95 −0.33; P < 0.05). CONCLUSION: This systematic review and meta-analysis have demonstrated that the therapy of CMF had a notable curative effect on relieving oxidative stress in STZ-induced DKD rats and CMF was significantly more effective than the WM control group. For the clinical application, the results providing confidence and some theoretical reference for DKD via evaluating the efficacy of CMF to a certain extent. SYSTEMATIC REVIEW REGISTRATION: [PROSPERO], identifier [CRD42022313737].