Type 2 diabetes mellitus is associated with endothelial dysfunction, which contributes to increased cardiovascular risk. Chronic hyperglycemia induces oxidative stress and reduces nitric oxide bioavailability, leading to impaired endothelial function. Resveratrol, a natural polyphenol with antioxidant and anti-inflammatory properties, has been shown to improve endothelial function in experimental studies.

This randomized controlled trial aims to evaluate the effectiveness of resveratrol supplementation in improving endothelial dysfunction and metabolic control in patients with type 2 diabetes mellitus. Endothelial function will be assessed using flow-mediated dilatation (FMD) of the brachial artery and serum endothelial nitric oxide synthase (eNOS) levels. Metabolic parameters including fasting blood glucose, postprandial glucose, HbA1c, and lipid profile will also be evaluated.

Type 2 diabetes mellitus (T2DM) is associated with an increased risk of cardiovascular disease, in which endothelial dysfunction plays a central role. Chronic hyperglycemia leads to oxidative stress and increased production of reactive oxygen species, resulting in decreased nitric oxide bioavailability and impaired endothelial function.

Resveratrol (3,5,4-trihydroxystilbene) is a natural polyphenol with antioxidant, anti-inflammatory, and endothelial-protective effects. Previous experimental and clinical studies have suggested that resveratrol may improve endothelial function through enhancement of endothelial nitric oxide synthase (eNOS) activity and reduction of oxidative stress.

This study is a randomized controlled trial involving patients with type 2 diabetes mellitus and endothelial dysfunction. Participants will be randomized to receive either resveratrol 50 mg or placebo for 12 weeks. Endothelial function will be evaluated using flow-mediated dilatation (FMD) of the brachial artery and serum eNOS levels before and after intervention.

Metabolic control will be assessed by measuring fasting blood glucose, postprandial glucose, HbA1c, and lipid profile including LDL, HDL, and triglycerides. The primary objective is to determine whether resveratrol supplementation improves endothelial function, while secondary outcomes include changes in metabolic parameters and safety evaluation.

This study aims to provide evidence regarding the role of resveratrol as an adjunct therapy in improving endothelial function and metabolic control in patients with type 2 diabetes mellitus.

Inclusion Criteria:

• Adults aged 18-65 years
• Diagnosed with type 2 diabetes mellitus
• Evidence of endothelial dysfunction
• Stable antidiabetic therapy for at least 3 months prior to enrollment
• Willing to participate and provide informed consent

Exclusion Criteria:

• Type 1 diabetes mellitus
• Acute or chronic infection
• History of cardiovascular events (e.g., myocardial infarction, stroke)
• Severe renal impairment or hepatic dysfunction
• Pregnancy or breastfeeding
• Use of antioxidant supplements or investigational drugs within the last 3 months
• Known allergy or contraindication to resveratrol

Participants, care providers, investigators, and outcome assessors will be blinded to group allocation. Resveratrol and placebo will be identical in appearance and packaging.