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  Background & Objectives: With respect to the importance of diabetes mellitus prevalence and contradictory role of treatment with metformin on vitamin B12 and folic acid serum levels and this study was done in order to determine of Vitamin B12 and folic acid serum level in patients with diabetes mellitus under treatment with metformin. This research was performed in diabetes center of Kashan in 2004.

  Methods: Information about research method, target and conclusions were given to patients. Those who were under treatment with anti acids, and chemotherapy drugs and also those who were alcoholic and had gastrointestinal diseases and hepatic diseases were excluded among all samples of this research, then patients were divided in to 2 groups: The first group were under treatment with metformin, second group were with other drugs for diabetes treatment. All of people were under treatment for at least 6 months folic acid, vitamin B12 serum level of them were checked after 14 hours fasting and the findings were studied with SPSS software and X2 tests, T test fisher exact test.

  Results: there were 145 (84.31%) female and 27 male (15.69%) between 172 patients. Average age of patients was 52.1±12.7 years. Duration of disease was 5.42±9.1 and average Body Mass Index was 27.7±4.7 kg/m2. Folic acid average was 9.2±5.1 (ng/dl) in patients who consumed metformin and was 8.7±4.6 (ng/dl) in patients without consuming of metformin that did not show significant difference (p=0.557). B12 vitamin average was 5.43±342.54 (pg/dl) in patients under treatment with metformin and was 516±32.16 (pg/dl) in patients without consuming metformin in statistical findings between these 2 groups was not significant. (p=0.639). Significant correlation was observed between age of patients whom were studied and serum folic acid level of them. (p=0.07), But did not show significant correlation between age with serum B12 level (p=0.095). There was no significant correlation between age, length of disease, body mass index and level of B12 and folic acid.

  Conclusion: Correlation between reduction serum level of B12 and folic acid with consuming of metformin was not found. Difference between results of this study with other studies is likely because of more use of routine vitamin supplement that is consumed by patients without physician’s recommending, genetic differences or drugs composition.

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Background & objectives: PCOS is one of the most prevalent endocrinology disorders and 5-15% of women in fertility age suffer from this disease. The leptin a 167 amin oacid peptide is secreted from adipose tissue in a pulsatile fashion. This hormone is essential in regulation of normal body weight and like the klotho hormone that is expressed most prominently in the distal convoluted tubules of kidneys and the choroid plexus of brain, has a role in pathogenesis of reproductive disorders. The secreted klotho has been identified as an anti-aging and anticancer hormone. Metformin is an anti-hyperglycemic drug with anorexic properties that could influence the function of ovaries.

Methods: In this case-control study, 45 patients with PCOS who referred to the infertility center of Jahad-e-Daneshgahi in the city of Ardabil from March 2013 through March 2014, were selected in accordance with the NIH criteria. Moreover, 45 healthy women were also selected as the control group. BMIs were calculated by division of weight by square of height and insulin resistance index was calculated by HOMA-IR model. Leptin and klotho serum levels were measured using ELISA kit. In the case group the measurements were repeated after a one-month course of therapy with metformin. Data analysis performed by SPSS software using dependent and independent t-tests.

Results: PCOS patients showed significant improvements after receiving metformin for one month.
Patients’ weights showed some decline. Fasting plasma glucose levels and insulin resistance decreased significantly (p<0.01). Hormonal assays indicated significant decrease in leptin and insulin levels and rise in Klotho levels. BMIs did not change meaningfully. Measurements of leptin and klotho levels showed a decrease in mean leptin levels from 34.74 to 28.41 ng/l and the level of klotho increased from 4.01 to 5.43 ng/l.

Conclusion: This study showed that metformin treatment can cause a rise in klotho and a decrease in leptin levels without considerable effects on the weights of women with PCOS. Probably, leptin exerts its physiological effects in low concentrations while klotho in contrast acts physiologically in higher concentrations.

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Background & objectives: Type 2 diabetes mellitus (DM) is a metabolic disorder that is common throughout the world. Meta-analysis is a statistical technique in which the results of two or more independent studies, with similar objectives, are mathematically combined in order to improve the reliability of the results. The aim of this study was to compare the efficacy of metformin and linagliptin in patients with type 2 diabetes.
Methods: To identify relevant studies, PubMed, ISI Web of Science, Embase, Cochran library, Scopus and Ovid databases were searched from January 2000 to August 2016. Mean difference (MD) with 95% confidence interval (CI) for efficacy were calculated and pooled analysis was performed using Stata V.12 and RevMan V.5.3 software.
Results: Four studies recruiting1260 patients with DM (682 patients in group linagliptin and 578 patients in metformin group) were included in this study. The MD of HbA1C outcome of 0.5 mg linagliptin was effective (0. 7295, % CI = 0. 69 - 0. 75). The MD of fasting blood sugar (FBS) test revealed that linagliptin was effective at 0.5mg (MD = 36.79, 95% CI = 35.20 - 38.38) and 5 mg (MD = 12.65, 95% CI = 2.68 to 22.63) doses.
Conclusion: Our results suggest that some doses of linagliptin versus metformin may be an effective treatment for DM2. However, the number of studies was limited, and further research is needed.
 

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Background & objectives: Epidemiological Studies have shown that diabetes increase the risk of developing Alzheimer’s disease (AD).also several studies have confirmed that long term use of Metformin (Met) improves cognitive function in diabetic patients.  The aim of the present study was to investigate the effects of Met on learning and memory in diabetic and non-diabetic rats.
Methods: Animals were divided into 2 groups including healthy and diabetic group. In healthy group, normal rats subdivided into control, saline and Met groups which received saline or Met (500mg/kg) and in diabetic group including DM, DM+saline and DM+Met subgroups, diabetic rats  received saline or Met (100, and 200mg/kg) for 20 days. Diabetes was induced by intraperitoneal injection (ip) of streptozotocin (STZ).
Results: Our results showed that Met (500mg/kg, ip) impaired spatial learning but improved spatial memory in normal rats. The results also showed that Met improved learning and memory in diabetic rats in a dose dependent manner, so that the rats of DM+Met group compared to DM+saline group found platform in less time and with less distance traveled. Met also increased the percentage of time elapsed and the distance swum in the target quadrant in diabetic rats during the probe trial.
Conclusion: An intraperitoneal injection of STZ resulted in a significant decline in learning and memory and treatment with Met can enhance learning and memory in a dose dependent manner, therefore, it is useful for treatment of cognitive impairment in diabetic patients.