Caftaric Acid Blunts MMP9 Activity and Expression in CAM Angiogenesis Model: In vitro and In vivo Evaluation by Targeting NFkB/VEGF/MMP-9 Signaling in Diabetic Retinopathy

Introduction: Caftaric acid (CFA), a natural product, has been experimentally proven to have diverse pharmacological properties. The nexus of NF-kB/VEGF/MMP9 signaling is believed to be associated with angiogenesis and vascular complications in patients with diabetic retinopathy (DR). The aim and objectives of the study are to explore the therapeutic relevance of CFA in DR, particularly focusing on pathological angiogenesis mechanisms involving the NF-κB / VEGF / MMP-9 signaling pathway associated with DR. To assess the anti-angiogenic potential of CFA using the CAM (Chorioallantoic Membrane) and cell culture-based models. Methods: The cytotoxicity screening of CFA was performed using Human Retinal Pericyte cells (HRPCs). In vitro free radical (DPPH, OH, NO) assays were performed for CFA and standard ascorbic acid. An in vitro CAM assay of CFA and standard bevacizumab (15 μg/mL) was performed to assess angiogenesis in the CAM. In vivo STZ assay for CFA (100 and 200 mg/kg; oral) and standard epalrestat (150mg/kg/day; oral) were performed to observe the intensity of DR by using male Wistar albino rats. After the last dose of test and standard drug administration, all animals were sacrificed to carry out biochemical, western blotting, and histopathological analysis. Results: The CFA showed concentration-dependent scavenging activity of DPPH, NO, and OH radicals comparable to that of the standard ascorbic acid. Significant antiangiogenic effects were observed for CFA (100 and 250 μg/mL), with scores of 1 and 1.6, respectively. CFA (200μg/mL; CAM model) and CFA (200 mg/kg; STZ model) significantly reduce VEGF, MMP9, and NF-κB expressions. Discussion: VEGF and MMP9 are major drivers of angiogenesis and vascular permeability, and their inhibition by CFA suggests a reduction in retinal angiogenesis and vascular leakage. Its mechanism involves modulation of the NFκB/VEGF/MMP-9 signaling pathway, leading to reduced pathological angiogenesis in both in vitro and in vivo models. This reinforces the CFA's potential in mitigating the pathological features of DR. Conclusion: CFA demonstrates significant anti-angiogenic and anti-inflammatory potential by suppressing MMP-9 activity and expression. These findings suggest that CFA could serve as a promising therapeutic candidate for managing diabetic retinopathy by targeting abnormal angiogenesis and inflammation. other: Nil