The effect of Sambucus nigra L. extract and phytosinthesized gold nanoparticles on diabetic rats

Nanomaterials such as gold nanoparticles (NPs) conjugated with natural products have shown good results in lowering the glycated hemoglobin and have an anti-inflamatory effect. The aim of our study is to evaluate the antidiabetic effect of NPs functionalized with Sambucus nigra L. (SN) extract on experimental model of diabetes in rats. Diabetes was induced to 18 Wistar male rats (n = 6) by a single intramuscular injection of streptozotocin (30 mg/kg body weight - b.w.). SN extract (15 mg/kg b.w.), NPs (0.3 mg/kg b.w.) and vehicle (normal saline) were administered by gavage once a day, every morning, for 2 weeks. Other 18 animals were used as control groups and were treated with the same compounds, at the same time. Afterwards, blood, liver and muscle samples were taken to assess the oxidant/antioxidant status and the liver for the evaluation of metalloproteinases (MMP)-2 and 9 activities, COX-2 and NFKB expressions and for immunohistochemistry. Serum glycemia, cholesterol, alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) were also measured. The administration of NPs extract increased the muscle and systemic GSH/GSSG ratio in the diabetic group vs. diabetic (p<0.03) or non-diabetic groups treated with vehicle (p<0.05) and decreased MDA levels compared to non-diabetic group (p<0.05). COX-2 expression (p<0.0001) and proMMP-2 activity (p<0.05) decreased after pretreatment with NPs in parallel with the reduction of Kupffer cells percent (<0.001). No morphological abnormalities were detected in histopathology. NPs present a great potential for further usage as adjuvants in the diabetic therapy due to the increase of antioxidant defence and reduction of MMPs activity and inflammation in liver tissue. (C) 2016 Elsevier B.V. All rights reserved.