Therapeutic Effect of Abelmoschus manihot on Type 2 Diabetic Nonproliferative Retinopathy and the Involvement of VEGF

Abstract

Objective. To evaluate the efficacy of Abelmoschus manihot in treating type 2 diabetic nonproliferative retinopathy. Methods. It was a randomized controlled clinical trial. The recruited eighty subjects with type 2 diabetic nonproliferative retinopathy were randomly divided into treatment group and control group. The two groups received basic treatments including control of blood glucose, blood pressure and blood lipid, management of diet, exercise and health education, and monitoring of relevant indicators. Additionally, the treatment group was given oral administration of Abelmoschus manihot. All subjects were followed up on monthly basis for consecutive six months. The related parameters including diabetic retinopathy (DR) incidence rates, “Early Treatment Diabetic Retinopathy Study” (ETDRS) vision scores, retinal thicknesses in macular region, serum vascular endothelial growth factor (VEGF) levels, and biochemical indicators of both groups before and after treatment were accurately collected and statistically analyzed. Results. There were no significant differences of DR severity levels, ETDRS vision scores, macular retinal thicknesses such as cube average thickness (CAT), central subfield thickness (CST), and cube volume (CV), and serum VEGF levels between two groups before treatment. Meanwhile, there were no significant differences of demographic characteristics, case terminations, blood glucose, blood lipid, blood pressure, biochemical indicators of hepatorenal function, hypoglycemic drugs, hypotensive drugs, and other basic treatments between two groups during six months treatment. The present study suggested that the remission rate of DR and the ETDRS vision score in the treatment group were significantly higher than those of the control group (remission rate: 25.4% vs 9.3%, P=0.01; ETDRS score: 78 (72, 82) vs 72 (67, 80), P=0.0002) while the progression rate of DR in the treatment group was significantly lower than that of the control group (progression rate: 4.2% vs 18.7%, P=0.007) after six months treatment. In addition, the CAT, CST, CV, and serum VEGF levels of the treatment group were significantly improved after the treatment (CAT: 286 (278, 302) vs 282 (270, 295) μm, P<0.0001; CST: 251 (239, 274) vs 248 (235, 265) μm, P<0.0001; CV: 10.3 (10.0, 10.9) vs 10.1 (9.7, 10.6) mm3, P<0.0001; VEGF: 0.21 (0.14, 0.58) vs 0.16 (0.10, 0.23) ng/ml, P=0.0026), while there were no significant differences of the control group before and after treatment (CAT: 287 (279, 294) vs 287 (279, 295) μm, P=0.27; CST: 250 (240, 266) vs 252 (238, 266) μm, P=0.72; CV: 10.4 (10.1, 10.6) vs 10.4 (10.1, 10.7) mm3, P=0.53; VEGF: 0.21 (0.13, 0.66) vs 0.23 (0.12, 0.64) ng/ml, P=0.85). Conclusion. The study offered the novel evidence for the therapeutic effect of Abelmoschus manihot on type 2 diabetic nonproliferative retinopathy, which was associated with improved VEGF. This trial is registered with ChiCTR1800019292.

Hyperoside improves diabetic retinopathy by regulating TGF-β1/miR-200b/VEGF pathway

“…Our previous study has proven that Abelmoschus manihot could improve DR severity, ETDRS vision, macular edema, and serum VEGF levels in type 2 diabetes (7). Hyperoside is a primary active ingredient of Abelmoschus manihot (29), and the hyperoside content level in Abelmoschus manihot is notably higher compared with other herbal medicines (30).…”

“…The recent clinical study of our team indicated that Abelmoschus manihot could improve the severity of DR, ETDRS vision scores and macular edema in type 2 diabetes, and the speci c therapeutic mechanism seemed to be associated with inhibited vascular endothelial growth factor (VEGF) levels, which needed further investigations (7). Previous studies have showed that the activation of transforming growth factor-beta 1 (TGF-β1)/micro-RNA 200b (miR-200b)/VEGF pathway by high glucose might play an essential role in the destruction of blood-retinal barrier (BRB) and the pathogenesis of DR (8-10).…”

Neuroinflammation and neovascularization in diabetic eye diseases (DEDs): identification of potential pharmacotherapeutic targets

“…As a result, the principal treatment technique for neovascular eye illnesses is the inhibition of VEGF activity. Zingiber zerumbet (L.) ERK1/2 and NF-κB [121] Dendrobium chrysotoxum Lindl Protein kinase C and NF-κB [122] Polygonum cuspidatum High-mobility group box-1 (HMGB1) [123] Salvia miltiorrhiza (Lamiaceae) Ang-II-induced NADPH oxidase-4 (Nox4) [124] Lycium barbarum (Solanaceae) Caspase-3, PPAR- [125] Astragalus membranaceus (Fabaceae) ERK1/2, NFkB, VEGF [126,127] Ginkgo biloba HIF-1α and VEGF [128] Puerariae lobata (Fabaceae) AGEs, VEGF [129] Vaccinium myrtillus VEGF/VEGFR2 [130] Lonicerae japonicae Flos VEGF/VEGFR2 [131] Abelmoschus Manihot VEGF/VEGFR2 [132] Fructus Arctii VEGF/VEGFR2 [133] RAS/VEGF pathway: The angiotensin with its receptor complex energizes the expression of VEGF during ONV by activating NF-kB.…”