Effect of Berberine Versus Metformin on Glycemic Control, Insulin Sensitivity and Insulin Secretion in Prediabetes

Pre diabetes (PD) is a term that refers to alterations in glucose homeostasis, including impaired fasting glucose (IFG), Imparied glucose tolerance (IGT) or both, involving a higher risk to develop type 2 diabetes mellitus (T2DM) in 10 years.

The efficacy of pharmacotherapy in the prevention of diabetes in adults with prediabetes has been demonstrated, the first line of pharmacology treatment is metformin, on the other hand, the traditional Chinese and Ayurverica medicine offer potential active substances for the treatment of hyperglucemia like berberine.

Berberine is an extract with hypoglycemic effects in animal models as well as in clinical trials in type 2 diabetes mellitus even compared to metformin, for this reason comparing it's activity against metformin in prediabetes would provide impact information on a new alternative treatment and compare with the standard pharmacological treatment.

The aim of the study evaluate the effect of administration of berberine versus metaformine on glycemic control, insulin secretion and insulin sensitivity in patients with pre diabetes.

The investigators hypothesis is that the administration of berberine versus metformin modifies glycemic control, insulin sensitivity and insulin secretion in patients with prediabetes.

A randomized, double-blind, placebo-controlled clinical trial in 28 patients with a diagnosis of prediabetes (IFG and IGT) in accordance with the American Diabetes Association with out treatment.

They will be assigned randomly two groups of 14 patients, one of the groups will receive 850 mg of metformin twice at day (before breakfast and before dinner) and one pill of placebo (before lunch) for 14 weeks. There will be a running period, starting with a dose of 500 mg the first week, the second week increasing to 1000 mg and from the third to the fourteenth week will be a dose of 1500 mg.

The other group will receive 500 mg of berberine three times at day (each one before the mealtime) for14 weeks. There will be a running period, starting with a dose of 850 mg the first week, the second week dose of 850 mg of metformin plus one placebo pill and from the third week to the fourteenth week will be a dose of 1700 mg ( two 850 mg metformin pills) plus one placebo pill.

They will be measured fasting blood glucose, postprandial glucose levels and glycosylated hemoglobin, and will be calculated Area Under Curve of glucose and insulin, total insulin secretion (Insolinogenic index), first-phase of insulin secretion (Strumvoll index) and insulin sensitivity (Matsuda index).

This protocol it's already approved by the local ethics committee and written informed consent it's going to be obtained from all volunteers.

Statistical analysis will be presented through measures of central tendency and dispersion, average and deviation standard for quantitative variables; frequencies and percentage for qualitative variable. Qualitative variables will be analyzed by X2, will be used for differences inter-group Mann-Whitney U Test and Wilcoxon Test for the within-groups differences. It will be considered statistical significance p≤0.05.

Eligibility Criteria:
Inclusion Criteria:

* Patients both sexes
* Age between 31 and 60 years
* Diagnosis of prediabetes according 2 ADA criteria (fasting blood glucose levels between 100-125 mg/dl and postprandial blood glucose levels after an oral glucose tolerance test with 75 of oral glucose between 140-199 mg/dl)
* Body Mass Index from 25 to 34.9kg/m2
* Informed consent signed

Exclusion Criteria:

* Women with confirmed or suspected pregnancy
* Women under lactation and/or puerperium
* Hypersensibility to ingredients of intervention
* Physical impossibility for taking pills
* Known uncontrolled renal, hepatic, heart or thyroid diseased
* Diabetes diagnosis
* Previous treatment for glucose
* Body Mass Index ≥35 kg/m2
* Glycosylated hemoglobin \> 6.5%
* Triglycerides ≥500 mg/dL
* Total cholesterol ≥240 mg/dL
* Low density lipoprotein (c-LDL) ≥190 mg/dL
* Blood Pressure ≥140/90 mmHg