Dog Retinol Binding Protein ELISA Kit

Background and Objectives: The aim of the present study was to evaluate the relationship between retinol and risk of diabetic retinopathy in Chinese adults. Methods and Study Design: Eighty-six subjects with type 2 diabetes mellitus (T2DM) and 40 healthy subjects (healthy comparison group, HCG) were recruited in Beijing Luhe Hospital. Of the 86 T2DM subjects, 43 subjects were diagnosed with diabetic retinopathy (DRG), and 43 subjects had no retinopathy (DNRG). Results: Dietary intake of retinol (p<0.001) and retinol equivalent (p<0.05) was significantly higher but serum retinol and (p<0.001) retinol binding protein 4 (RBP4) (p<0.05) were significantly lower in DNRG compared with HCG. Dietary intake of retinol (p<0.05) and retinol equivalent (p<0.05) was significantly lower, and serum retinol and (p<0.01) retinol binding protein 4 (RBP4) (p<0.01) were significantly higher in DRG compared with DNRG. In T2DM subjects, per 100 mu g/day higher dietary retinol intake was associated with 17% lower risk of diabetic retinopathy (odds ratio (OR), 0.83; 95% CI, 0.70 to 0.98; p=0.032), and after adjusting for potential confounding factors, the OR was 0.82 (95% CI, 0.69 to 0.99; p=0.036); per 100 mu g/day higher in dietary retinol equivalent intake was associated with 12% lower risk of diabetic retinopathy (OR, 0.88; 95% CI, 0.79 to 0.97; p=0.010), and after adjusting for potential confounding factors, the OR was 0.88 (95% CI, 0.79 to 0.98; p=0.025). Conclusions: Higher dietary intake of retinol or retinol equivalent is associated with lower risk of diabetic retinopathy.

Aims The aim of this study was to investigate the association between retinol-binding protein 4 (RBP4) and diabetic retinopathy (DR) among patients with type 2 diabetes mellitus (T2DM). Methods Databases PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure, VIP, and Wangfang were searched to July 30, 2019. The Newcastle-Ottawa Scale was applied to assess the quality of all identified studies, and those qualified were included in the meta-analysis. The Chi squared Q test and I-2 statistics were conducted to evaluate heterogeneity. Standardized mean differences (SMD) and 95% confidence intervals (CI) among RBP4 within the DR and T2DM without retinopathy (DWR) groups were pooled using the random effects model depending on the heterogeneity. Subgroup analyses were conducted among the groups having different diabetes duration, detection methods, body mass index, and total cholesterol and triglyceride levels. The funnel plot was used to assess publication bias. Results Nineteen observational studies were included in our meta-analysis. RBP4 was significantly higher in both nonproliferative DR (SMD: 0.72, 95% CI 0.48-0.95, P < 0.00001) and proliferative DR (SMD: 2.68, 95% CI 1.69-3.67, P < 0.00001) groups despite high heterogeneity (I-2 = 87 and 97% in DR and PDR groups, respectively). Significant differences were noted among most subgroups (P < 0.05). Among those accompanied by hypercholesterolemia, the association between RBP4 and DR were unclear (P = 0.09). Conclusions Elevated RBP4 is strongly associated with DR and may play an essential role in its progression. Additional large-scale controlled studies are needed to confirm these findings.