The neuroprotective effects of icariin on ageing, various neurological, neuropsychiatric disorders, and brain injury induced by radiation exposure.

Epimedium brevicornum Maxim, a Traditional Chinese Medicine, has been used for the treatment of impotence, sinew and bone disorders, "painful impediment caused by wind-dampness," numbness, spasms, hypertension, coronary heart disease, menopausal syndrome, bronchitis, and neurasthenia for many years in China. Recent animal experimental studies indicate that icariin, a major bioactive component of epimedium may effectively treat Alzheimer's disease, cerebral ischemia, depression, Parkinson's disease, multiple sclerosis, as well as delay ageing. Our recent study also suggested that epimedium extract could exhibit radio-neuro-protective effects and prevent ionizing radiation-induced impairment of neurogenesis. This paper reviewed the pharmacodynamics of icariin in treating different neurodegenerative and neuropsychiatric diseases, ageing, and radiation-induced brain damage. The relevant molecular mechanisms and its anti-neuroinflammatory, anti-apoptotic, anti-oxidant, as well as pro-neurogenesis roles were also discussed.

Efficacy of Shouzhangshen (Rhizoma Gymnadeniae Crassinervidis) extract against acute high altitude hypoxia-induced brain injury in mice.

OBJECTIVE: To evaluate the protective effect of Shouzhangshen (Rhizoma Gymnadeniae Crassinervidis) extract against acute high altitude hypoxia-induced brain injury in mice. METHODS: Sixty C57BL/6J mice were selected and assigned to six groups (n = 10): normal control group, low-pressure hypoxia group, positive control group (dexamethasone 500 mg/kg), and three groups treated with Shouzhangshen extract (250, 500, and 750 mg/kg, respectively). The Morris water maze test was performed to evaluate alterations in spatial learning and memory deficits. Nissl staining was performed to detect Nissl bodies and neuron damage. Hypoxia-inducible factor (HIF)-1α, interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), and malondialdehyde (MDA) expression in brain tissue and serum, as well as superoxide dismutase (SOD) and glutathione (GSH) activity in brain tissues were measured by enzyme-linked immunosorbent assays, quantitative real-time-polymerase chain reaction and western blots. RESULTS: The Morris water maze test results showed that Shouzhangshen extract can significantly reduce the latency and swimming distance to escape onto a visible platform, increase neuron density and hierarchy and the number of pyramidal neurons, and decrease the expression of HIF-1α, IL-1ß, TNF-α, and VEGF mRNAs and proteins in both brain tissue and serum (P < 0.05). Furthermore, significantly lower MDA expression and higher GSH activity were detected in the three groups treated with Shouzhangshen compared with the low-pressure hypoxia group (P < 0.05). However, no significant alteration was observed for SOD activity (P > 0.05). CONCLUSION: Our findings suggest that Shouzhangshen extract may have a significant effect on acute high altitude hypoxia-induced brain injury in mice.

Investigation of the protective effect of Paeonia lactiflora on Semen Strychni-induced neurotoxicity based on monitoring nine potential neurotoxicity biomarkers in rat serum and brain tissue.

Semen Strychni has been widely used as a traditional Chinese herb medicine, but its clinical use was limited for its potential neurotoxicity and nephrotoxicity. This study aimed to investigate S. Strychni-induced neurotoxicity and the neuro-protective effect of Paeonia lactiflora based on monitoring nine potential neurotoxicity biomarkers in rat serum and brain tissue. A sensitive liquid chromatography-tandem mass spectrometry method was developed and validated to monitor serotonin, tryptophan, dopamine, tyrosine and glutamate in serum and five brain regions (prefrontal cortex, hippocampus, striatum, cerebellum and hypothalamus). Analytes were separated on a CAPCELL CORE PC column (150 mm × 2 mm, 2.7 µm) with a gradient program of acetonitrile-water (0.2 % formic acid) and a total runtime of 7.5 min. In addition, enzyme-linked immunosorbent assay was conducted to determine four kinds of protein (tryptophan hydroxylase, tyrosine hydroxylase, endogenous brain-derived neurotrophic factor and nerve growth factor). Results demonstrated that the administration of S. Strychni could cause certain endogenous substances disorder. These analytes were found significantly changed (p < 0.05) in serum (except glutamate) and in certain tested brain regions in S. Strychni extract group. Pretreatment of P. lactiflora could significantly reverse the S. Strychni-induced neurotoxicity and normalize the levels of such endogenous substances. The study could be further used in predicting and monitoring neurotoxicity caused by other reasons, and it was expected to be useful for improving clinical use of S. Strychni through pretreatment with P. lactiflora.