Hypolipidemic effects of Hypericum Scabrum extract on the serum lipid profile and obesity in high-fat diet fed rats.

Diets included high-fat (HFD) and high calories intake is correlated with greater risk of obesity and oxidative stress, which lead to increase the risk of related diseases such as cardiovascular and metabolic disease. In the present study, we have examined the hypolipidemic activity of Hypericum Scabrum extract on HFD fed rats. Fifty-four male Wistar rats divided into six groups: 1) control, 2) H. Scabrum extract (100 mg/kg gavage per day), 3) H. Scabrum extract (300 mg/kg), 4) HFD, 5) HFD and H. Scabrum extract (100 mg/kg), 6) HFD and H. Scabrum extract (300 mg/kg). The groups were fed their diet and treatment for 3 months. Biochemical analysis showed elevated lipid serum profile in HFD rats compared to control group. H. Scabrum extract supplementation significantly ameliorated triglyceride, total cholesterol and LDL-cholesterol. H. Scabrum extract supplementation leading to increase HDL-cholesterol in HFD treated groups. This experiment showed that H. Scabrum extract decreased HFD complications and might be beneficial herbal drug for treatment of hyperlipidemia and obesity.

Coenzyme Q10 supplementation reverses diabetes-related impairments in long-term potentiation induction in hippocampal dentate gyrus granular cells: An in vivo study.

Diabetes mellitus (DM) is associated with impaired hippocampal synaptic plasticity. Coenzyme Q10 (CoQ10) acts as an antioxidant and exerts neuroprotective effects. Accordingly, this study aimed at evaluating the effects of CoQ10 on hippocampal long-term potentiation (LTP) and paired-pulse facilitation (PPF) in streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were randomly divided into six groups (n = 8 per group) as follows and treated for 90 days: the control, control + low dose of CoQ10 (100 mg/kg), control + high dose of CoQ10 (600 mg/kg), diabetic, diabetic + low dose of CoQ10, and diabetic + high dose of CoQ10 groups. Diabetes was induced by a single intraperitoneal injection of 50 mg/kg STZ. The population spike (PS) amplitude and slope of excitatory post synaptic potentials (EPSPs) were measured in dentate gyrus (DG) area in response to the stimulation applied to the perforant path (PP). The results showed that the STZ-induced diabetes impaired LTP induction in the PP-DG synapses. This finding is supported by the decreased EPSP slope and PS amplitude of LTP (P < 0.05). Both low- and high-dose CoQ10 supplementation in the control and diabetic animals enhanced EPSP slope and PS amplitude of LTP in the granular cells of DG (P < 0.05). PPF was affected by LTP induction in diabetic animals receiving the high dose of CoQ10 (P < 0.05). It is suggested that CoQ10 administration could attenuate deteriorative effect of STZ-induced diabetes on in vivo LTP in the DG. The enhanced transmitter release can be partly one of the possible underlying mechanism(s) responsible for the LTP induction in the diabetic animals treated with CoQ10.

Investigation of protective effects of coenzyme Q10 on impaired synaptic plasticity in a male rat model of Alzheimer's disease.

Oxidative stress plays a key role in contributing to ß-amyloid (Aß) deposition in Alzheimer's disease (AD). Coenzyme Q10 (Q10) is a powerful antioxidant that buffers the potential adverse consequences of free radicals. In this study, we investigated the neuroprotective effects of Q10 on Aß-induced impairment in hippocampal long-term potentiation (LTP), a widely researched model of synaptic plasticity, which occurs during learning and memory, in a rat model of AD. In this study, 50 adult male Wistar rats were assigned to five groups: control group (saline); sham group; intraventricular PBS injection, Aß group; intraventricular Aß injection, Q10 group; and Q10 via oral gavage and Q10 + Aß group. Q10 was administered via oral gavage, once a day, for 3 weeks before and 3 weeks after the Aß injection. After the treatment period, in vivo electrophysiological recordings were performed to quantify the excitatory postsynaptic potential (EPSP) slope and population spike (PS) amplitude in the hippocampal dentate gyrus. LTP was created by a high-frequency stimulation of the perforant pathway. Following LTP induction, the EPSP slope and PS amplitude were significantly diminished in Aß-injected rats, compared with sham and control rats. Q10 treatment of Aß-injected rats significantly attenuated these decreases, suggesting that Q10 reduces the effects of Aß on LTP. Aß significantly increased serum malondialdehyde levels and total oxidant levels, whereas Q10 supplementation significantly reversed these parameters and increased total antioxidant capacity levels. The present findings suggested that Q10 treatment offers neuroprotection against the detrimental effects of Aß on hippocampal synaptic plasticity via its antioxidant activity.