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Background & aim: Nowadays because of difficulty in the supply and injection of insulin and blood sugar reducing drugs and considering the side effects of chemical drugs, researcher’s attention is drawn to using herbal medicines. Liver is one of the organs affected by diabetes in different functional aspects. The purpose of this research was studying the effect of Rosa canina extract on reducing the adverse effects and improving diabetes symptoms related to histophysiology, amount of biochemical serum factors and liver enzymes in male rats.

Methods: 32 male Wistar rats, weighed 200-220 gr, were divided into 4 groups. Diabetes was induced by intraperitoneal injection of STZ (60mg/kg). The period of experiments was 4 weeks. At the end of experiments, the rats were sacrificed and their serums were collected for measurement of liver enzymes. Also, histological sampling of liver was done. Statistical analysis was performed using analysis of variance (one-way ANOVA).

Results: The results of this study showed that treatment with ethanol extract of Rosa canina led to significant reduction of liver enzymes in the Rosa extract-treated groups in comparison with the diabetic group, indicating the protective effect of alcoholic extract of Rosa canina on liver tissue against diabetes-induced damages. In liver histopathology, a distinct fat change in the lobular center areas was created in the diabetic group. Pathological changes were not significant in the liver of the Rosa extract-treated groups; liver in this group was relatively healthier than in diabetic group.

Conclusions: Rosa extract improved this organ's function in STZ-induced diabetic rats by reducing serum biomarkers of liver pathology and reducing histological damages.

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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.
 

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Background & objectives: Alzheimer’s disease (AD) patients suffer from anxiety and depression. Sodium hydrosulfide (NaHS) can remit the depressive-like and anxiety-like behaviors induced by diabetes mellitus. We aimed to investigate the effects of chronic administration of hydrogen sulfide on depressive and anxiety-like behaviors in the Streptozotocin (STZ) rat model of AD.
Methods: Animals were divided into: Control, NaHS, and Alzheimer’s rats group include (STZ, STZ + Saline and STZ + NaHS groups) which were the Alzheimer’s rats and received Saline and NaHS (5.6 mg/kg per d) for 21 days. For induction of AD, STZ (3 mg/kg, 10 μl/injection site) was administered into the lateral ventricles. The behavioral consequences were assessed using plus maze, forced swim and sucrose preference tests.
Results: Our results showed that intracerebroventricular (i.c.v.) injection of STZ decreased the percentage of open arm time and entries, indicating anxiety-like effects. It also increased the duration of immobility time and decreased the percentage of sucrose preference indicating depression-like effects. Sodium hydrosulfide administration in STZ-treated rats increased the percentage of open arm time and entries, indicating anxiolytic-like effects. It also decreased the duration of immobility time and increased the percentage of sucrose preference, indicating antidepressant-like effects.
Conclusion: STZ administration can induce depression- and anxiety-like symptoms in rats, and Sodium hydrosulfide treatment, decreased the depression- and anxiety-like symptoms in STZ rat Model of AD, suggests that Sodium hydrosulfide can be useful in the treatment of affective disorders in AD patients.