Effects of date seeds administration on anxiety and depressive symptoms in streptozotocin-induced diabetic rats: biochemical and behavioral evidences.

OBJECTIVES Several epidemiological data indicate that chronic hyperglycemia is associated with behavioral changes such as anxiety and depressive symptoms. Date seeds, one of the most potent products with potential antioxidant activities and possess many benefits against hyperglycemia and its complication. The aim of the current study was to explore the potential effect of date seeds extract on biochemical and behavioral changes (anxiety and depression) in streptozotocin (STZ)-diabetic rats. METHODS Rats were divided into four groups as follows: normal control, diabetic control, diabetic treated with the lyophilized aqueous extract of the date seed (2,000 mg/kg) (LAE-DS) and diabetics treated with insulin (4 UI/day). Experimental diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg). After 24 days treatment period, anxiety and depressive behaviors were evaluated using four behavioral tests. After sacrifice, blood samples were collected to evaluate lipid parameters. In addition, rat organs (kidney, liver and brain) were dissected out in order to estimate lipid peroxidation levels as oxidative stress marker. RESULTS Oral administration of the lyophilized aqueous extract of date seeds and insulin injection for 30 days significantly decreased blood glucose levels in STZ-diabetic rats and protected them against undesirable changes in lipid parameters, including cholesterol, triglycerides, LDL cholesterol, VLDL cholesterol and atherosclerosis index. Compared to untreated diabetic rat, a significant decrease in lipid peroxidation levels in kidney, liver and brain (Hippocampus and prefrontal cortex) were observed after treatment with insulin or LAE-DS in diabetic rats. Furthermore, insulin and LAE-DS administration prevented anxiety-related behaviors in STZ-diabetic rats. CONCLUSIONS Therefore, it would be possible to combine this extract with insulin and use it as an antioxidant supplement for type 1 diabetic patients.