Moringa oleifera Seed Extract Alleviates Scopolamine-Induced Learning and Memory Impairment in Mice.

The extract of Moringa oleifera seeds has been shown to possess various pharmacological properties. In the present study, we assessed the neuropharmacological effects of 70% ethanolic M. oleifera seed extract (MSE) on cognitive impairment caused by scopolamine injection in mice using the passive avoidance and Morris water maze (MWM) tests. MSE (250 or 500 mg/kg) was administered to mice by oral gavage for 7 or 14 days, and cognitive impairment was induced by intraperitoneal injection of scopolamine (4 mg/kg) for 1 or 6 days. Mice that received scopolamine alone showed impaired learning and memory retention and considerably decreased cholinergic system reactivity and neurogenesis in the hippocampus. MSE pretreatment significantly ameliorated scopolamine-induced cognitive impairment and enhanced cholinergic system reactivity and neurogenesis in the hippocampus. Additionally, the protein expressions of phosphorylated Akt, ERK1/2, and CREB in the hippocampus were significantly decreased by scopolamine, but these decreases were reversed by MSE treatment. These results suggest that MSE-induced ameliorative cognitive effects are mediated by enhancement of the cholinergic neurotransmission system and neurogenesis via activation of the Akt, ERK1/2, and CREB signaling pathways. These findings suggest that MSE could be a potent neuropharmacological drug against amnesia, and its mechanism might be modulation of cholinergic activity via the Akt, ERK1/2, and CREB signaling pathways.

A novel PPARα/γ agonist, propane-2-sulfonic acid octadec-9-enyl-amide, ameliorates insulin resistance and gluconeogenesis in vivo and vitro.

Peroxisome proliferator-activated receptor alpha/gamma (PPARα/γ) agonists have emerged as important pharmacological agents for improving insulin action. Propane-2-sulfonic acid octadec-9-enyl-amide (N15) is a novel PPARα/γ dual agonist synthesized in our laboratory. The present study investigates the efficacy and safety of N15 on insulin resistance regulation in high fat diet (HFD)-and streptozotocin (STZ)-induced diabetic mice and in palmitic acid (PA)-induced HepG2 cells. Our results showed that N15 remarkably ameliorated insulin resistance and dyslipidemia in vivo, as well as rectified the glucose consumption and gluconeogenesis in vitro. Moreover, the glucose-lowering effect of N15 was associated with PPARγ mediated up-regulation of hepatic glucose consumption and down-regulation of gluconeogenesis. Meanwhile, N15 exerted advantageous effects on glucose and lipid metabolism without triggering weight gain and hepatotoxicity in mice. In conclusion, our data demonstrated that by alleviating glucose and lipid abnormalities, N15 could be used as a potential prophylactic and therapeutic agent against type 2 diabetes and related metabolic disorders.

Oleoylethanolamide attenuates apoptosis by inhibiting the TLR4/NF-κB and ERK1/2 signaling pathways in mice with acute ischemic stroke.

This study was carried out to investigate the exact mechanisms behind the neuroprotective effects of oleoylethanolamide (OEA) after acute cerebral ischemic injury. Transient focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 min followed by reperfusion. OEA (40 mg/kg, ip) was administered with a single injection upon reperfusion. The number of apoptotic cells was detected by TUNEL staining. The expression of Bax, Bcl-2, and TLR4, as well as the activities of NF-κB, Akt, and ERK1/2 were analyzed by western blot. Our data showed that OEA treatment alleviated cell apoptosis in a mouse model of ischemic stroke, accompanied by suppression of Bax, as well as upregulation of antiapoptotic protein Bcl-2 level. The changes of Bax and Bcl-2 could not be observed in PPARα knockout mice models with OEA administration. Importantly, OEA inhibited MCAO-induced TLR4 expression, NF-κB activation, IκBα degradation, and ERK1/2 phosphorylation. Our findings demonstrated that the neuroprotective effects of OEA on cerebral ischemia may be attributed to its antiapoptotic property achieved, at least in part, through the PPARα signaling and inhibition of both TLR4/NF-κB and ERK1/2 signaling pathways. These results provide new evidence indicating the neuroprotective effect of OEA on ischemic stroke.

Chronic oleoylethanolamide treatment improves spatial cognitive deficits through enhancing hippocampal neurogenesis after transient focal cerebral ischemia.

Oleoylethanolamide (OEA) has been shown to have neuroprotective effects after acute cerebral ischemic injury. The aim of this study was to investigate the effects of chronic OEA treatment on ischemia-induced spatial cognitive impairments, electrophysiology behavior and hippocampal neurogenesis. Daily treatments of 30 mg/kg OEA significantly ameliorated spatial cognitive deficits and attenuated the inhibition of long-term potentiation (LTP) in the middle cerebral artery occlusion (MCAO) rat model. Moreover, OEA administration improved cognitive function in a manner associated with enhanced neurogenesis in the hippocampus. Further study demonstrated that treatment with OEA markedly increased the expressions of brain-derived neurotrophic factor (BDNF) and peroxisome proliferator-activated receptors α (PPARα). Our data suggest that chronic OEA treatment can exert functional recovery of cognitive impairments and neuroprotective effects against cerebral ischemic insult in rats via triggering of neurogenesis in the hippocampus, which supports the therapeutic use of OEA for cerebral ischemia.