Background: Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the potential anti-diabetic effect of the medicinal plant Crocus sativus (Saffron) and the augmenting effect of its consumption on the memory and mental health, this study was conducted to evaluate the effect of chronic interaperitoneal administration of Crocus. S extract on learning and memory in diabetic rats.Methods: In this experimental study a total of 60 male rats were divided into normal and diabetic groups. Then, each of these groups was divided into three subgroups. Two of these subgroups received 30 and 60 mg/kg crocus. S extract in the treatment periods, but the third group didn’t receive any treatment. At the end of treatment period, each of these subgroups was evaluated by two ways: Ymaze (alternative behavior percentage) and shuttle box (initial latencies (IL) and step-through latencies (STL)) in passive avoidance test. Finally, obtained data were subjected to one way ANOVA test and post hoc Tokey analysis.Results: Treatment of the diabetic animals with the extract could antagonized the augmenting effect of diabetics on initial latency (P<0.05). Also, treatment of the diabetic rats with the extract (60 mg/kg) increased the reduced step through latency time (recall of the data) induced by diabetic in the animals (P<0.05). However, obtained data from Y maze test show that the extract could not improved the spatial memory disruption due to diabetics.Conclusion: Chronic Crocus. S injection is effective on the capability of maintaining information in the stores memory and reminding in the diabetic rats. However, the extract could not improve the spatial memory in the diabetic rats.

Purpose: Fumaria parviflora Lam (Fumariaceae) has been used in traditional medicine in the treatment of several diseases such as diabetes. The present work was designed to evaluate the hypoglycaemic effects of methanolic extract (ME) of F. parviflora in normal and STREPTOZOTOCIN-induced diabetic rats.Methods: The rats used were allocated in six (I, II, III, IV, V and VI) experimental groups (n=5). Group I rats served as ‘normal control’ animals received distilled water and group II rats served as ‘diabetic control’ animals. Diabetes mellitus was induced in groups II, V and VI rats by intraperitoneal single injection of STREPTOZOTOCIN (STZ, 55 mg kg-1). Group V and VI rats were addi-tionally treated with ME (150 mg kg-1 day-1 and 250 mg kg-1 day-1, i.p. respectively) 24 hour post STZ injection, for seven consecutive days. Groups III and IV rats received only ME 150 mg kg-1 day-1 and 250 mg kg-1 day-1, i.p. respectively for seven days. The levels of blood glucose were determined using a Glucometer.Results: Administra-tion of F. parviflora extract showed a potent glucose lowering effect only on streptozo-tocin (STZ) induced diabetic rats below 100 mg/dl (P<0.001). However, no significant differences in the blood glucose levels were recorded between diabetic rats received 125 or 250 mg/kg of plant extracts.Conclusion: The findings of the study indicated that F. parviflora has significant hypoglycemic effect on STZ-induced diabetic rats with no effects on blood glucose levels of normal rats.

Objective(s): Diabetes is fundamentally connected with the inability of skeletal muscle. Sinapic acid (SA) has multiple biologic functions and is diffusely utilized in diabetic complications. The purpose of this study was to explore the potential improvement effect and mechanisms of SA in STREPTOZOTOCIN (STZ)-induced diabetic muscle atrophy. Materials and Methods: The model of diabetic mice was established by intraperitoneal STZ (200 mg/kg) to evaluate the treatment effect of SA (40 mg/kg/d for 8 weeks) on muscle atrophy. Muscle fiber size was assessed by Hematoxylin and Eosin (HE) staining. Muscle force was measured by a dynamometer. Biochemical parameters were tested by using corresponding commercial kits. The expressions of Atrogin-1, MuRF-1, nuclear respiratory factor 1 (NRF-1), peroxisome proliferative activated receptor gamma coactivator 1 alpha (PGC-1α ), CHOP, GRP-78, BAX, and BCL-2 were detected by Western blot. Results: Our data demonstrated that SA increased fiber size and weight of gastrocnemius, and enhanced grip strength to alleviate diabetes-induced muscle atrophy. In serum, SA restrained creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), tumor necrosis factor (TNF-a), and interleukin 6 (IL-6) levels, while enhancing total anti-oxidant capacity (T-AOC), superoxide dismutase (SOD) and catalase (CAT) levels to improve muscle injury. In gastrocnemius, SA promoted NRF-1, PGC-1α , and BCL-2 expressions, while inhibiting Atrogin-1, MuRF-1, CHOP, GRP-87, and BAX expressions. Conclusion: SA protected against diabetes-induced gastrocnemius injury via improvement of mitochondrial function, endoplasmic reticulum (ER) stress, and apoptosis, and could be developed to prevent and treat diabetic muscle atrophy.

Background and Objective: Chronic diabetes mellitus (DM) leads to cardiovascular dysfunction. Diosgenin is a natural steroidal saponin with cardiovascular protective potential. In this research study, the beneficial effect of diosgenin was evaluated on some markers of oxidative stress in cardia tissue of STREPTOZOTOCIN (STZ) -diabetic rats.Materials and Methods: Male Wistar rats (n=28) were divided into equal-sized control, diosgenin-treated control, diabetic, and diosgenin-treated diabetic groups. Diabetes was induced by a single intraperitoneal injection of STREPTOZOTOCIN (60 mg/kg). Diosgenin was administered p.o. at a dose of 40 mg/kg for 7 weeks. Some markers of oxidative stress including malondialdehyde (MDA), superoxide dismutase (SOD), catalase, and reduced glutathione (GSH) were measured in cardiac tissue homogenate.Results: It was found out that diabetic group had an elevated MDA content (p<0.01), reduced activity of SOD (p<0.05) and catalase (p<0.05) and a lower content of GSH (p<0.01) versus control group and chronic diosgenin treatment significantly reversed only MDA (p<0.05) and GSH (p<0.05) with no significant effect on SOD activity and catalase activity.Conclusion: Diosgenin could attenuate cardiac lipid peroxidation and improves non-enzymatic antioxidant defensive system in diabetic condition and it may be considered as a potential therapeutic agent to mitigate cardiac dysfunction in DM.

Background & Aim: Any disturbance in the function of central aminergic system is the main cause of depression in diabetes. Since most of the available antidepressants have limitations, it is necessary to research other options of treatment. The purpose of this study was the investigation of the possible antidepressant effect of melatonin on diabetic rats.Material and Method: This experimental study involved 40 male Wistar rats weighing 200±20 gr. The animals were divided into four groups: control, melatonin, diabetic, and melatonin-treated diabetic. Experimental diabetes was induced by intraperitoneal (i.p.) injection of 50 mg/kg STREPTOZOTOCIN. 72 hours after diabetes induction, melatonin (10 mg/kg/day, i.p.) was injected for 5 weeks. At the end of administration period, the modified forced swimming test (MFST) and the open-field test were used for evaluation of depression and its possible mechanism. The MFST evaluated climbing, swimming and immobility periods and the locomotor activity was evaluated by the open-field test. The experimental data were statistically analyzed by one-way analysis of variance (ANOVA) followed by Tukey test, using the software package SPSS v.15.Results: The swimming test shows that diabetes causes a significant (p<0.05) increase in immobility and climbing periods (as depression and noradrenergic system activity indices respectively) as compared with the control group. The swimming time (as serotonergic system activity index) and the locomotor activity (as dopaminergic system activity index) were significantly (p<0.05) decreased in diabetic rats as compared with the control group. Daily melatonin injection to diabetic rats significantly (p<0.05) modified all mentioned behavioral indices as compared with the diabetic group. Melatonin significantly (p<0.05) decreased the locomotor activity in non-diabetic rats as compared with the control group, whereas it did not have any significant effects on swimming, climbing or immobility periods in these animals.Conclusion: Melatonin has antidepressant effects in diabetes through modifying central aminergic system.