Iranian Journal of

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Background: Urtica dioica, or the stinging nettle, is recommended by ancient medical texts for the treatment of high blood sugar.
Methods: We set up a perifusion system, in which an exact number of islets of Langerhans were exposed to an active component of the leaf extract of Urtica dioica, obtained by TLC. The active component was then injected into the peritoneum of both normal and diabetic rats to evaluate response in vivo.
Results: There was a marked increase in insulin secretion in vitro, as determined by ELISA. In vivo, there was an increase in blood insulin content following intraperitoneal injection. The increase in serum insulin observed at 60 minutes was associated with a decrease in blood glucose, checked several times during the observation period. Maximum insulin release over 120 minutes was equal to five times the baseline value. The decrease in blood sugar correlated with both the timing and magnitude of insulin release.
Conclusion: Notwithstanding the magnitude of the changes observed, the results obtained in normal and diabetic rats were similar.

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In this article, we review animal models of types 1 and 2 diabetes mellitus. Models of type 1 diabetes are discussed in two parts, genetic and chemical. Models of type 2 diabetes are discussed in four parts – rat and mouse models, dietary induction, and selective breeding. Models are assessed regarding metabolic disturbances, the condition of the pancreas, long-term complications, and research benefits.

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Background: Leptin, a peptide hormone, is the product of "ob" Gene. Leptin regulate body weight and composition through reducing appetite and energy expenditure in rodents and humans. The aim of this study was to evaluate differences in expression of Leptin Gene in different tissues of streptozotocin induced diabetic rats.
Methods: 40 Sprague Dawely rat were selected. Intra peritoneal injection was carried out in 20 rats and another 20 rats were used as control. After injection of 60mg/kg Streptozotocin, animals were transformed into diabetic. Glucose was measured by glucose oxidase method. Leptin and insulin were measure by commercially available immunoassay kits. After one week treatment, different tissues including adipose tissues, Spleen, epidydimis, and Liver of both control and experimental animals were dissected. For investigation of any changes of the Leptin gene expression in different tissues, RNA was extracted using Trizo1 method. By using RT-PCR technique, Leptin cDNA and β-actin cDNA as internal control were constructed and PCR was carried out. The RT-PCR products were detected on 2% agarose gel using electrophoresis.
Results: Mean serum levels of Leptin was 5.23± 0.45 ng/ml before injection of streptozotocin and markedly decreased in STZ induced diabetic rats to 0.79±0.25 ng/ml. This decrease was statistically significant P<0.05). There was a direct and significant correlation between leptin and insulin in streptozotocin-induced diabetic rats (r=0.37, P<0.05 ) while, this was reverse in control rats ( r= -0.28, P<0.05). Using RT-PCR method, Leptin gene expression in different tissues including fat epidydimis, liver, and spleen showed that the intensity of leptin band with 452 bp was decreased in diabetic rats in comparison to normal rats. Actin Gene expression was identified in PCR products having 403 bp and the intensity was constant in both groups. The reduction rates of "ob" mRNA in fat epidydimis tissue in STZ diabetic rats was remarkable in comparison to Spleen and Liver.
Conclusion: It is speculated that Leptin gene could be under regulation of insulin dependent mechanism in diabetic rats and by modulating Leptin gene expression in diabetic patients, it may be useful in clinical practices.

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Background: Due to the progress of diabetes and the use of alternative herbal medicines, In this study, the effects of oral administration of the mucilage extracted from pods of Abelmoschus esculentus (Ae) fruits on serum levels of glucose, lipids and morphology of Langerhans islets in diabetic rats was investigated.
Methods: In this experimental study, 24 female wistar rats were randomly allocated into four groups (n=6): normal control (NC), diabetic control (DC) and 2 diabetic groups that received (oral) 300 and 500 mg/kg/body weight of Abelmoschus esculentus. After preparing and confirming the type of, mucilage extraction from the fruit’s green okra was done by evaporation device in vacuum. Diabetes mellitus was induced by single dose intraperitoneal injection of streptozotocin 60mg/kg/body weight in diabetic groups. After 4 weeks, the serum levels of glucose and lipid profile of all groups were analyzed. Also morphology of Langerhans islets in the 4 groups was evaluated using H&E staining method. The data analyzed by SPSS software using ANOVA and Tukey tests.
Results: The results indicate a significant increase (P<0/05) in glucose, cholesterol, triglyceride, LDL and significant decrease (P<0.05) in HDL in diabetic rats compared to normal control. The use of the mucilage extracted from A. esculentus caused a significant decrease in serum levels of glucose, cholesterol, triglyceride, LDL and significant increase in serum level of HDL comparison with diabetic group.
Conclusion: according to the results of this study, the mucilage extracted from A. esculentus could be effective on control hyperlipidemia and hyperglycemia caused by diabetes mellitus.

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Background: Cytokines are immune related factors. Production of pro inflammatory cytokines in diabetic patients is increased, which is exacerbated by vigorous training. This study investigates the response of serum IL-2 and IL-4 to eight-week high Intensity Interval Training (HIIT) with caffeine intake on inflammatory and anti-inflammatory responses in diabetic rats.
Methods: In a clinical-interventional animal study, 50 male rats were randomly assigned to 5 equal groups (control group (C), diabetes group (D), diabetes + caffeine group (D+Ca), diabetes + training group (D+T), diabetes + training + caffeine group (D+Ca+T)) and subjected to 8 weeks of caffeine supplementation (70 mg / kg of caffeine powder was injected five days each week) and 8 weeks of 5 sessions per week with 6 to 12 times, 2-min intervals with intensity of 85-90% of maximal speed. 48 hours after the last training session, immunological factors including IL-2 and IL-4 were measured. Statistical analysis of variables was performed using One-way ANOVA and Tukey tests at the significant level (P<0.05).
Results: The results showed that (D+Ca) group had the lowest IL2 in comparison with (D) group (P= 0.001). IL-4 had the highest in (D+Ca) and (D+Ca+T) groups (P = 0.001). But these differences were not statistically significant between (D+Ca) and (D+Ca+T) groups (P= 0.67).
Conclusion: It seems that caffeine to play a role in improving the status of IL-2 and IL-4 in streptozotocin-induced diabetes, but HIIT exercises are not effective in this regard.

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Background: The pathway of insulin messengers is so important that diabetes can lead to disruption of this pathway. However, the aim of this study was to investigate the effect of 8 weeks of endurance training on protein Kinase-B (PKB or AKT) and mechanical target of rapamycin (mTOR) in the left ventricle of the heart of diabetic rats induced by streptozotocin and nicotinamide.
Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with streptozotocin and Nicotinamide, rats were randomly assigned to two groups, training and control (6 heads in group each). The rat training program was performed on a treadmill for 8 weeks and 4 sessions per week, including 30 minutes of endurance training with an intensity of about 50 to 70% of the maximum speed. SPSS software and independent t-test were used to analyze the data.
Results: Eight weeks of endurance training resulted in a significant increase in protein Kinase-B content (P=0.03); But no significant change in Protein Mechanistic Target of Rapamycin content was observed in the endurance training group compared to the control (P=0.97).
Conclusion: protein Kinase-B is a key protein for regulating many cellular pathways, which was significantly increased by eight weeks of endurance training. Due to the fact that the content of protein mechanistic target of rapamycin does not change, it is possible that endurance training cannot lead to physiological hypertrophy heart through the mTORC1 pathway.

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Background: AMPK and P53 proteins regulate the TOR protein in the TORC1 complex, which regulates many physiological processes. The aim of this study was to evaluate the effect of AMPK and P53 proteins on the TOR pathway following endurance training in the left ventricle of the heart of diabetic rats by streptozotocin and nicotinamide.
Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with streptozotocin and Nicotinamide, rats were randomly assigned to two groups, training and control (6 heads in group each). The training group performed endurance training on a treadmill for rodents for 6 weeks and 4 sessions per week for 42 minutes with an intensity of about 50 to 70% of the maximum speed. SPSS software version 23 and independent t-test were used to analyze the data.
Results: Six weeks of endurance training led to significant increase in the protein content of AMPK (P=0.009) and TOR (P=0.005) between training and control groups in the left ventricular tissue of the heart muscle. In contrast, a significant decrease in P53 protein content was observed between the training and control groups in the left ventricular tissue of the heart muscle (P=0.0001).
Conclusion: The results showed that endurance training can with increase the content of AMPK and TOR proteins and decrease the content of P53 protein to regulate processes such as metabolism, mitochondrial biogenesis, cardiac hypertrophy, inhibition of autophagy in the hearts of diabetic subjects.
 

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Diabetes is a serious public health problem in low- and middle-income countries. There is a strong association between hyperglycemia, oxidative stress and the development of diabetes. Therefore, screening and early diagnosis of this disease in people at high risk can be effective in preventing these complications. The main route of insulin signaling is to control lipid and glucose metabolism, and its imbalance leads to type 2 diabetes. P-Cymene is an aromatic monoterpene with a wide range of therapeutic properties including antioxidant activity. The aim of this study was to evaluate the effect of p-Cymene at a dose of 50 mg / kg in preventing the symptoms of diabetes and serum factors.
Materials and Methods: 30 male Wistar rats weighing approximately 250 g were randomly selected and divided into five groups: control, diabetic control (sham), metformin-treated diabetic (met), and non-diabetic treated. P-Cymene and diabetics treated with P-Cymene were divided.  One week after streptozotocin injection, treatment with P-Cymene at a dose of 50 mg / kg was performed by sunflower oil solvent for 28 days by gavage. At the end of the experiment, blood samples were taken from the hearts of rats and the parameters of glucose, insulin, and superoxide dismutase (SOD) were measured.
Results: The results showed that diabetes increased water and food intake as well as glucose levels and decreased insulin (P <0.001) and superoxide dismutase activity in rats and administration of P-Cymene extract improved the symptoms of diabetes and oxidative stress in Became diabetic rat.