Effects of hydroxytyrosol on cardiovascular biomarkers in experimental diabetes mellitus

Abstract

The aim of this study was to assess the influence of hydroxytyrosol (HT) on cardiovascular biomarkers and morphometric parameters of the arterial wall in streptozotocin-diabetic rats. Seven groups of rats (N=10 per group) were studied for 2 months: nondiabetic rats (NDR), diabetic rats treated with saline (DR) and DR treated with HT (0.5, 1, 2.5, 5 and 10 mg kg day p.o.). DR had higher platelet aggregation values, higher thromboxane B, plasma lipid peroxidation, 3-nitrotyrosine, oxidized LDL (oxLDL), myeloperoxidase, vascular cell adhesion molecule 1 (VCAM-1) and interleukin-1β (IL-1β) concentrations, and lower aortic 6-keto-prostaglandin F and nitric oxide production than NDR. Aortic wall area and smooth muscle cell count were also higher in DR than in NDR. HT significantly reduced both oxidative and nitrosative stress, oxLDL concentration, VCAM-1 and inflammatory mediators, platelet aggregation and thromboxane B production. Morphometric values in the aortic wall were reduced to values near those in NDR. In conclusion, HT influenced the major biochemical processes leading to diabetic vasculopathy, and reduced cell proliferation in the vascular wall in this experimental model.

Hydroxytyrosol in the Prevention of the Metabolic Syndrome and Related Disorders

“…In a clinical trial enrolling healthy volunteers, it has been demonstrated that sunflower oil supplemented with HT decreased vascular cell adhesion protein (VCAM-1) plasmatic concentration (45–50 mg/kg/day × 3 weeks) [89] and monocyte chemoattractant protein-1 and interleukin-8 receptor expression (366 mg/kg/day × 3 weeks) [87]. Such results were confirmed in rodent models, where HT reduced platelet aggregation, VCAM-1 and IL-1β expressions (0.5 to 10 mg/kg/day × 2 months) [84] and TNF-α expression (0.04%) [74]. Interestingly, Gonzalez et al [60] reported that HT (4 mg/kg/day × 2 months) reduced the size of atherosclerotic lesions in rabbits fed with a high fat and high cholesterol diet.…”

“…Given the fact that OLE is degraded into HT, the question arose if the blood pressure lowering effect was due to OLE or HT. Lopez-Villodres et al [84] found that HT supplementation (10 mg/kg/day × 2 months) increased in diabetic rats the levels of nitrites and nitrates, potent donors of NO acting as vasorelaxing agent. In addition, Storniolo et al [85] demonstrated that HT (10 µM) counteracted hyperglycemia-induced endothelin-1 expression, a well-known hypertensive agent, in a more extend than oleic acid.…”

“…Lopez-Villodres et al [84] found that in streptozotocin-induced model of diabetes, HT supplementation (10 mg/kg/day × 2 months) increased the level of nitrates and nitrites. HT was reported to be ineffective on eNOS expression and activity (i.e., phosphorylation on its Ser1177) in absence of oxidative stress in HUVECs (0.1 to 100 µM) [134].…”

Hydroxytyrosol: Health Benefits and Use as Functional Ingredient in Meat

“…In addition, HXT consumption can regulate glutathione concentration and provides antioxidant enzymes to adipose tissue [ 32 ]. Moreover, in other in vivo study with experimentally induced diabetes mellitus in rats, it was shown that the HXT consumption influenced the major biochemical processes leading to diabetic vasculopathy and reduced cell proliferation in the vascular wall [ 33 ]. It is confirmed the prevention against damage by oxidative stress induced by this compound, which acted as regulator of cell protection and damage induction, controls the intracellular redox state.…”

Comparison of the anti-angiogenic potential of hydroxytyrosol and five derivatives

“…2 In the last years, scientific evidence has accumulated pointing to the pleiotropic effects of HT on multiple targets. In fact, demonstrated beneficial effects of HT for human health include its antidiabetic, 3,4 antifungal, 5 antiinflammatory, 6 antiparasitic, 7 cardio- 8 and neuroprotective 9 activities. HT has also beneficial effects on metabolic syndrome 10 and antitumoral effects of HT have been reported.…”