Diabetic Mellitus (DM) is a multiple metabolic disorder that leads to abnormal metabolism in carbohydrates, fats and protein, causing hyperglycaemia and hyperlipidaemia. Millions of people have been affected by the development of diabetic complications, which is still a major endocrine disease. It generally promotes the risk of macro and microvascular disorders in many organs, such as the heart, kidney, retina and brain. However, it has been shown that persistent hyperglycaemia can promote glucose auto-oxidative and protein glycosylation, increase polyol and hexosamine pathways and induce protein kinase activation that causes changes in the inflammatory mediator's grade. Transitional mechanisms may produce reactive oxygen species (ROS) in DM, which directly contribute to the elevation of oxidative stress in various tissues. ROS induces oxidative stress that plays a pathological role in the development and progression of diabetic complications. STZ is known to have toxic effects on pancreatic Β-cells and may be used as a potential inducer of oxidative stress. The recent study referred to the use of STZ as a diabetic inducer in experimental animals. Intraperitoneal injection of STZ leads to shrinking of the islet of Langerhans cell size with severe architectural disarray. Moreover, it was found that the development of diabetic complications was associated with an increased risk of morbidity and mortality from cardiovascular disease. It is found in a myocardial biopsy from diabetic animals that many cardiac morphological abnormalities, including cardiomyocyte hypertrophy, increased quantities of matrix collagen and perivascular fibrosis were recorded. In addition to mitochondrial dysfunction, endoplasmic reticulum stress and endothelial dysfunction were also observed. In recent years, scientific attention has been focused on the search for safe and effective medicinal plants that can prevent or delay the development of diabetic complications.[11-13] The bioactive constituents of green plants modulate carbohydrate and lipids metabolisms, decrease glyceamia and insulin resistance and optimise oxidative stress of DM due to their antioxidants’ activities. The present investigation is concerned with pancreatopathy and cardiopathy as a progressive consequence of diabetic complications and the study of potential plant extracts that contain natural products as antidiabetic agents or biological compounds, such as antioxidants that have a protective effect against the pathogenesis of such disease. Onopordum acanthium (OAE), or cotton thistle, is a species belonging to the family of Asteraceae used in Europe and Asia as a traditional medicine.