Mohammed Hayder Asker¹ , Saja Muzahem Thaker², Hadeel Kamil Khaleel³, Marwah Mohammed Nasri⁴, Ahmed Mohammed Nasri⁵

Abstract

Purpose: To investigate the modulatory effect of chronic supplementation with vitamin B6 (pyridoxine) in estrogen-deficiency-induced cardiovascular perturbations in OVX female rabbits. Methods: A total of 18 adult female rabbits were randomly divided into three groups (n = 6 each). Control group received no treatment; group 1 underwent ovariectomy (OVX) and was left untreated; group 2 was ovariectomized and exposed to pyridoxine (10 mg/kg/day orally over 12 weeks). Serum cardiac biomarkers (cardiac troponin T and lipocalin-2), nitric oxide synthase (NOS), and metabolic indices were measured. Histological examination of myocardial tissue was done to determine structural damage, fibrosis, and inflammation. Also, expression of endothelial nitric oxide synthase gene (NOS3) in cardiac tissue was determined using quantitative real-time PCR. Results: Treatment with pyridoxine significantly reduced myocardial injury markers and increased NOS activity to similar values as control (p < 0.05). Histopathological analysis following pyridoxine treatment did not damage myocardial structure, with increased fibrosis and inflammatory cell infiltration. At the molecular level, NOS3 was significantly increased following treatment with pyridoxine compared to other groups, indicating better endothelial functionalities (p < 0.05). Conclusion: The study showed that vitamin B6 significantly reduced myocardial injury improves endothelial function with no damage to myocardial tissues.