The effect of captopril on inflammation-induced liver injury in male rats

Zingiber officinale (Ginger) hydroalcoholic extract improved avoidance memory in rat model of streptozotocin-induced diabetes by regulating brain oxidative stress

OBJECTIVES

Diabetes mellitus associated cognitive impairment is suggested to be due to oxidative stress. Considering the anti-diabetic, antioxidant, antihyperlipidemic, and anti-inflammatory effects of Zingiber officinale, the present study aimed to investigate its effect on memory and oxidative stress factors in streptozotocin (STZ)-induced diabetic rats.

METHODS

The rats were allocated into five groups: Control, Diabetic, Diabetic + Ginger 100, Diabetic + Ginger 200, and Diabetic + Ginger 400. Following diabetes induction by STZ (60 mg/kg), 100, 200, or 400 mg/kg Ginger was given for eight weeks. Passive avoidance test (PA) was done and thiol, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) measurements were carried out in the brain.

RESULTS

The latency into the dark compartment decreased (p<0.001) and the number of entries and time spent in the dark chamber increased in the Diabetic group compared to the Control (p<0.001 for all). All three doses of extract improved performance of the rats in the PA test (p<0.001 for all). The hippocampal and cortical MDA level was higher (p<0.001) while CAT, SOD, and total thiol were lower (p<0.01-p<0.001) in the Diabetic group than the Control. Treatment with 200 and 400 mg/kg Z. officinale extract reduced hippocampal and cortical MDA (p<0.001) and improved CAT (p<0.001) while, just the dose of 400 mg/kg of the extract increased SOD and total thiol in hippocampal and cortical tissues (p<0.001) compared with Diabetic group.

CONCLUSIONS

Z. officinale extract could improve memory by reducing the oxidative stress in STZ-induced diabetes model.

The Effects of Incensole Acetate on Neuro-inflammation, Brain-Derived Neurotrophic Factor and Memory Impairment Induced by Lipopolysaccharide in Rats

Incensole acetate (IA) is a major component of Boswellia serrata resin that has been shown to have anti-inflammatory, anti-oxidant and neuroprotective properties. The present study determined the effect of IA on lipopolysaccharide (LPS)-induced memory impairment, and hippocampal cytokines and oxidative stress indicators level. We used 32 Wistar rats (220-250 g weight) randomly divided into four groups. The control group, which only received the saline-diluted DMSO (vehicle); LPS group which received LPS and was treated with the vehicle; and two IA-treated groups which received 2.5 or 5 mg/ kg IA before LPS injection. Morris water maze (MWM) and passive avoidance (PA) tests were performed. Finally, the brains were removed and were used to assess cytokines levels and oxidative stress status. Compared to the LPS group, IA administration reduced the time spent and path traveled to reach the hidden platform during 5 days of learning in MWM while increased the time spent in the target quadrant in the probe test. Moreover, IA increased latency while decreased entry number and time spent in the dark chamber of PA test compared to the LPS group. Additionally, pre-treatment with IA attenuated interleukin(IL)-6, tumor necrosis alpha (TNF-α), glial fibrillary acidic protein (GFAP), malondialdehyde (MDA) and nitric oxide (NO) metabolites levels while increased those of IL-10, total thiol, superoxide dismutase (SOD), catalase (CAT) and brain-derived neurotrophic factor (BDNF). Our results indicated that IA improved LPS-induced learning and memory impairments. The observed effects seem to be mediated via a protective activity against neuro-inflammation and brain tissue oxidative damage and through improving BDNF.