ligustilide and Cognition-Disorders

Ligustilide (LIG) is a principal active ingredient of traditional Chinese medicine, Radix Angelica sinensis, which has versatile pharmacological activities including neuroprotection. Previous studies have demonstrated that LIG has beneficial effects on cognition deficits associated with cerebral damage or neurodegenerative disorders. In present study, we investigated the neuroprotective effect of LIG on cognitive impairment and neurotoxicity in the brain of aging mouse induced by d-galactose (d-gal). The aging model mice were induced by subcutaneous (S.C.) injection of d-gal once daily for 8 weeks and LIG (80 mg/kg) was simultaneously administered orally. The Morris water maze (MWM) test was used to assess the spatial learning and memory abilities. The activity of Na(+)-K(+)-ATPase and the content of lipid peroxidation product malondialdehyde (MDA) in brain were examined. The levels of glial fibrillary acidic protein (GFAP), growth-associated protein GAP-43, and cleaved caspase-3 in brain were also determined by immunohistochemistry. The MWM test showed that LIG administration markedly improved behavioral performance of d-gal treated mice. This action could be partly explained by the results that LIG reduced the level of MDA as well as increased the activity of Na(+)-K(+)-ATPase in the brain of d-gal induced aging mice. Moreover, LIG significantly raised the expression of GAP-43 and reduced cleaved caspase-3 and GFAP levels in the brain of d-gal treated mice. These results demonstrated that LIG improves d-gal-induced cognitive dysfunction and brain toxicity, which suggests that LIG may be developed as a new medicine for the treatment of aged-related conditions.

Topics: 4-Butyrolactone; Aging; Animals; Brain; Cognition Disorders; Galactose; GAP-43 Protein; Gene Expression Regulation; Glial Fibrillary Acidic Protein; Male; Malondialdehyde; Maze Learning; Mice; Mice, Inbred ICR; Neuroprotective Agents; Neurotoxicity Syndromes; Sodium-Potassium-Exchanging ATPase; Statistics, Nonparametric

Radix Angelica Sinensis (RAS) has beneficial effects in patients suffering from cognitive impairment associated with chronic cerebral hypoperfusion. It has previously been demonstrated that RAS prevents the neurotoxic effects of β-amyloid (Aβ) in vitro, protects from injuries due to oxidative stress, inflammation and apoptosis and ameliorates scopolamine-induced amnesia in rats. Here, we studied the effects of RAS on cognitive improvement and neurogenic enhancement and examined the possible underlying mechanisms in a rat model with permanent bilateral common carotid artery occlusion, which serves as a model of chronic cerebral hypoperfusion-related neurodegenerative diseases. RAS enhances adult neurogenesis in the hippocampus following chronic cerebral hypoperfusion and improves the cognitive decline associated with hypoperfusion. Long-term ablation of adult hippocampal neurogenesis through cranial irradiation abolishes the protective effects of RAS on cognition. Furthermore, administration of RAS restores the decrease of brain-derived neurotrophic factor (BDNF) expression, the phosphorylation of cAMP-responsive element binding protein (CREB) and the glutamic acid decarboxylase 65 (GAD65) staining intensity in rats with chronic cerebral hypoperfusion. The present study supports the hypothesis that adult neurogenesis is required for RAS to facilitate recovery from the cognitive impairment induced by chronic cerebral hypoperfusion, while neurogenic enhancement secondary to RAS treatment may be due to increased BDNF and phosphorylated cAMP-responsive element binding protein (p-CREB) levels and increased γ-aminobutyric acid (GABA) expression. Based on the possible mechanisms suggested by the present study, this well-known traditional medicine may represent a candidate therapeutic agent for the treatment of dementia associated with vascular injury.

Topics: 4-Butyrolactone; Adult Stem Cells; Angelica sinensis; Animals; Blotting, Western; Cell Differentiation; Cognition Disorders; Cranial Irradiation; Disease Models, Animal; Drugs, Chinese Herbal; Hippocampus; Immunohistochemistry; Male; Neural Stem Cells; Neurodegenerative Diseases; Neurogenesis; Rats; Rats, Wistar

Previous studies have demonstrated that Z-Ligustilide (LIG), a characterized phthalide constituent present in numerous medical Umbelliferae plants, has significant neuroprotective effects in transient forebrain ischemia and permanent cerebral focal ischemia. The present study further investigated the effect of LIG on chronic cerebral hypoperfusion. Male Wistar rats were subjected to permanent ligation of both common carotid arteries (2VO). On Days 8-12 postsurgery, rat cognition was assessed in the Morris water maze. Rats with significantly impaired acquisition of spatial information were randomly allocated to three groups and orally administered LIG (10 or 40 mg/kg/day) or volume-matched vehicle on Days 13-40 post-2VO surgery. The sham-operated group served as controls. After long-term treatment with LIG, the impaired animals' behavioral, biochemical, and histopathological features were examined. Compared to the sham-operated group, significant cognitive impairment was observed in the vehicle-treated group 40 days after 2VO. Shortened mean escape latency was detected in the Morris water maze in rats treated with LIG (p<0.01 vs. vehicle-treated group) during the same trial days. Chronic 2VO-induced pathological changes included neuronal loss and an increase of glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes in the hippocampus. These effects were prevented with LIG treatment (p<0.01 vs. vehicle-treated group). LIG also significantly reduced malondialdehyde levels and increased superoxide dismutase activity in ischemic brain tissue (p<0.05 and p<0.01 vs. vehicle-treated group). In addition, LIG significantly increased choline acetyltransferase activity and inhibited acetylcholinesterase activity in ischemic brain tissues (p<0.05 and p<0.01 vs. vehicle-treated group). The present data demonstrate that LIG significantly prevented chronically hypoperfused cognitive deficits and brain damage at least partly through an antioxidant effect and improved cholinergic activity. The present findings suggest that LIG may have therapeutic potential in treating vascular dementia and cerebrovascular insufficiency.

Topics: 4-Butyrolactone; Acetylcholinesterase; Angelica sinensis; Animals; Antioxidants; Brain Chemistry; Brain Ischemia; Cerebrovascular Circulation; Choline O-Acetyltransferase; Cognition Disorders; Male; Maze Learning; Parasympathetic Nervous System; Prosencephalon; Rats; Rats, Wistar; Reversal Learning