Effect of Green Tea Extract on Arterial Stiffness in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) has become the epidemic of the XXI century. This chronic disease is also highly prevalent and primarily associated with an increased cardiovascular mortality and morbidity due to micro and macrovascular complications, where its pathophysiological mechanism accelerates the formation of the atherosclerotic process, fundamental element associated with arterial stiffness. The importance of anticipating the presence of a cardiovascular event lies precisely in the early detection of subclinical changes in the elastic arteries identified by measuring the pulse wave velocity. Having adequate pharmacological or non-pharmacological interventions that impact precisely in the reduction of pulse wave velocity contributes to a reduction of cardiovascular morbidity and mortality associated with DM2. Among non-pharmacological therapies they have been studied the benefits attributed to the use of green tea infusion either encapsulated or extract have been associated mainly with anti-inflammatory and antioxidant effects. There are both experimental and clinical studies that have shown benefits of administration of green tea (extract or infusion), and administered by different routes at different dosages and for varying times. But it has been noted that not all studies with green tea meet appropriate to draw conclusions about its benefits to cardiovascular level. However, it is proposed that the use of green tea extract with a highest amount of catechins through a controlled clinical trial could be a potential therapeutic strategy for changing hemodynamic alterations and arterial stiffness favorably in this particular group of patients DM2.

The objetive is to evaluate the effect of administration of Green tea exctract on arterial stiffness in individuals with T2DM. The investigators will conduct a double-blind trial, randomized, placebo control group, each group 12 male and female patients of 35-65 years of age with T2DM, with no hypertension or treated with insulins. Randomization will determine who will receive the intervention during 8 week trial (Green tea extract capsule, 400 mg 1 time daily with the first bite of each meal or approved placebo capsules), both groups also will continue with their usual treatment. The clinical findings and laboratory test include a metabolic profile and biosafety, wich will be baseline and at 8 weeks. Body weight, body fat, body mass index (BMI) and blood pressure will be determined during the inicial and final visit, likewise, hemodynamics parameters of arterial stiffness like the aortic pulse wave velocity (PWVao), central pulse pressure (PPao), aortic augmentation index (IAxao) and central systolic blood pressure (cSBP) by an oscillometric monitoring system via BPLab ®. Adverse events and adherence to treatment will be documented. The statistical analysis: Mann-Whitney U Test and Wilcoxon exact test. It is considered with significance at p\<0.05.

Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of T2DM
* Fasting plasma glucose \>126 and \<250 mg/dl at the time security
* Metformin monotherapy or with glibenclamide added
* Written informed consent

Exclusion Criteria:

* Hypertention
* Treated with insulin
* Use of antioxidant suplements or products with caffeine
* Woman pregnant or breastfeeding
* Untreated tyroid disease
* Total colesterol \>400mg/dl
* Triglycerides \>400mg/dl
* Liver enzimes (alt and ast) more tan twice the normal range
* Glomerular filtration rate \<60ml/min (Cockcroft-Gault)