Qiuxia Zhang

Induced cortical neurogenesis after focal cerebral ischemia – Three active components from Huang-Lian-Jie-Du Decoction

ETHNOPHARMACOLOGICAL RELEVANCE Huang-Lian-Jie-Du-Decoction (HLJDD) is a Traditional Chinese Medicine (TCM) clinical prescription noted for its neuroprotective effects. The total alkaloids, flavonoids, and iridoids are the main active components of HLJDD. In the present study we explored the possible effects of the total alkaloids, flavonoids, and iridoids from HLJDD on behavioral recovery and cortical neurogenesis after stroke. METHODS The stroke model was induced by permanent middle cerebral artery occlusion (pMACO). The total alkaloids (44 mg/kg), flavonoids (50 mg/kg), and iridoids (80 mg/kg) from HLJDD were orally administered for 2h after stroke and daily thereafter. Neurological function was assessed and then rats were sacrificed 7 days after pMACO. Following repeated intraperitoneal injections of the cell proliferation - specific marker 5-bromodeoxyuridine (BrdU) after stroke induction, precursor cell proliferation and differentiation was monitored by immunofluorescent staining. The levels of relevant proteins were determined by western blotting and the mRNA expressions were assessed by quantitative real time-polymerase chain reaction (qRT-PCR). RESULTS Total alkaloids, flavonoids and iridoids from HLJDD showed improved functional outcome after brain ischemia. The total alkaloids and iridoids increased number of BrdU-positive cells and enhanced neuronal differentiation in the cortex. Alkaloids-enhanced neurogenesis might be associated with increased VEGF, Ang-1, and Ang-2 protein expression. And the neuroproliferative effect of alkaloids was partially correlated with increased phosphorylation of AKT, and GSK-3β. Flavonoids treatment was found to promote differentiation of cortical precursor cells into neuronal but not glial cells, which may be at least attributable to the regulation of AKT, GSK-3β mRNA and Ang-1 protein levels. CONCLUSIONS Total alkaloids, iridoids and flavonoids from HLJDD promoted functional recovery likely via enhancing cortical neurogenesis and thus have potential as a treatment for ischemic brain injury.

Zuo-Gui and You-Gui pills, two traditional Chinese herbal formulas, downregulated the expression of NogoA, NgR, and RhoA in rats with experimental autoimmune encephalomyelitis

ETHNOPHARMACOLOGICAL RELEVANCE Zuo-Gui pills (ZGPs) and You-Gui pills (YGPs) are 2 traditional Chinese herbal formulas used for treating multiple sclerosis (MS) in the clinical setting and have been shown to have neuroprotective effects in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. The aim of this study was to explore the mechanisms underlying the neuroprotective functions of ZGPs and YGPs. MATERIALS AND METHODS Female Lewis rats were randomly divided into normal control, EAE model, 2g/kg ZGP-treated EAE, 3g/kg YGP-treated EAE, and prednisone acetate-treated groups. EAE model was induced by subcutaneous injection of MBP68-86 antigen. The neurological function scores were estimated. Histological structures of the brains and spinal cords were observed, and myelinated and axons imaged. NogoA, Nogo receptor (NgR), and RhoA transcript and protein levels were measured by real-time quantitative RT-PCR and western blotting on postimmunization (PI) days 14 (acute stage) and 28 (remission stage). RESULTS ZGPs and YGPs significantly reduced neurological functions scores and abrogated inflammatory infiltrates, demyelination, and axonal damage. Furthermore, treatment with ZGPs and YGPs inhibited NogoA, NgR, and RhoA mRNA and protein expression in rats at both the acute and remission stages. ZGPs exhibited stronger effects on NogoA and RhoA expressions, as well as neurological function, during the acute stage of EAE, while YGPs caused greater reductions in NogoA expression during the remission stage. CONCLUSIONS Our findings suggested that ZGPs and YGPs exerted neuroprotective effects by downregulation of NogoA, NgR, and RhoA pathways, with differences in response times and targets observed between ZGPs and YGPs.

Bushen Yisui Capsule ameliorates axonal injury in experimental autoimmune encephalomyelitis.

A preliminary clinical study by our group demonstrated Bushen Yisui Capsule (formerly called Erhuang Formula) in combination with conventional therapy is an effective prescription for the treatment of multiple sclerosis. However, its effect on axonal injury during early multiple sclerosis remains unclear. In this study, a MOG35-55-immunized C57BL/6 mouse model of experimental autoimmune encephalomyelitis was intragastrically administered Bushen Yisui Capsule. The results showed that Bushen Yisui Capsule effectively improved clinical symptoms and neurological function of experimental autoimmune encephalomyelitis. In addition, amyloid precursor protein expression was down-regulated and microtubule-associated protein 2 was up-regulated. Experimental findings indicate that the disease-preventive mechanism of Bushen Yisui Capsule in experimental autoimmune encephalomyelitis was mediated by amelioration of axonal damage and promotion of regeneration. But the effects of the high-dose Bushen Yisui Capsule group was not better than that of the medium-dose and low-dose Bushen Yisui Capsule group in preventing neurological dysfunction.

You-Gui pills promote nerve regeneration by regulating netrin1, DCC and Rho family GTPases RhoA, Racl, Cdc42 in C57BL/6 mice with experimental autoimmune encephalomyelitis

ETHNOPHARMACOLOGICAL RELEVANCE You-Gui pills (YGPs) are an effective traditional Chinese formula being used clinically for the treatment of multiple sclerosis (MS). Previous studies demonstrated that YGPs exerted the potent neuroprotective effects in murine models of experimental autoimmune encephalomyelitis (EAE), which is an equivalent animal model for multiple sclerosis (MS). However, the mechanism of YGPs functions remained unclear. AIM OF THIS STUDY The aim of this study was to evaluate the therapeutic effect of YGPs in MOG35-55-induced EAE mice and to further elucidate the underlying molecular mechanism. METHODS Female C57BL/6 mice were divided into six groups, including the non-treated EAE model, prednisone acetate- and 1.2, 2.4 or 4.8g/kg YGPs-treated EAE groups, and a normal control group. The EAE model was established by injecting the mice subcutaneously with MOG35-55 antigen. The body weights were measured and the neurological functions were scored in each group. The pathology and morphology of the brain and spinal cord was examined. The expression of MAP-2 was detected by immunofluorescent staining. The levels of netrin1, DCC, RhoA, Rac1, and Cdc42 were assayed by immunohistochemistry, qRT-PCR and Western blot on day 40 post-immunization (PI). RESULTS YGPs treatments significantly reduced neurological function scores in EAE mice, where the inflammatory infiltration was reduced and the axon and myelin damage in both brain and spinal cord was alleviated. In the brain and spinal cord tissues, YGPs increased the expression of neuronal factors MAP-2, netrin1 and DCC. The expression of Rac1 and Cdc42 were increased, while RhoA was reduced following YGPs treatments. CONCLUSION Our results demonstrated that YGPs exhibited a neuroprotective effect on promoting nerve regeneration at the brain and spinal cord in EAE mice induced by MOG35-55. Netrin1, DCC and the Rho family GTPases of RhoA, Racl, Cdc42 were involved in mediating the effects of YGPs on nerve regeneration.

BDNF/PI3K/Akt and Nogo-A/RhoA/ROCK signaling pathways contribute to neurorestorative effect of Houshiheisan against cerebral ischemia injury in rats.

ETHNOPHARMACOLOGICAL RELEVANCE Houshiheisan (HSHS), a classic traditional medicine prescription, has notable effects on patients with stroke AIM OF THE STUDY: To investigate the neurorestorative effects of HSHS on ischemic stroke and explore its mode of action. MATERIALS AND METHODS Focal cerebral ischemia models were induced by permanent middle cerebral artery occlusion (pMCAO). Male Sprague-Dawley (SD) rats were randomly divided into 5 experimental groups: sham vehicle, ischemia vehicle, pMCAO+HSHS at 5.1, 10.2g/kg, and pMCAO+Ginaton 0.028g/kg. HSHS or Ginaton was administrated 6h after pMCAO onset. Neurological function was assessed and then rats were sacrificed 7 days after MCAO. Cerebral ischemic injury was evaluated by hematoxylin and eosin (HE) staining and Neuronal nuclear antigen (NeuN) immunofluorescence analysis. The levels of BDNF were detected by enzyme linked immunosorbent assay (ELISA), and the expression levels of PI3K/Akt and Nogo-A/RhoA/ROCK2 signaling pathway were detected by western blot and quantitative real-time PCR (qRT-PCR). RESULTS Compared with those results of pMCAO group, HSHS 5.1 and HSHS 10.2 groups markedly improved neurological function, alleviated pathological damage, promoted the neuronal survival, increased the expression of BDNF, PI3K, Akt, in protein and mRNA, decreased the expression of Nogo-A, NgR, RhoA and ROCK2 in protein and mRNA 7 days after pMCAO. CONCLUSIONS The findings demonstrate that HSHS had significant therapeutic effects on ischemic stroke and it perhaps worked through the activation of BDNF/PI3K/Akt and down-regulation of Nogo-A/RhoA/ROCK signaling pathways.

Houshiheisan compound prescription protects neurovascular units after cerebral ischemia

Houshiheisan is composed of wind-dispelling (chrysanthemun flower, divaricate saposhnikovia root, Manchurian wild ginger, cassia twig, Szechwan lovage rhizome, and platycodon root) and deficiency-nourishing (ginseng, Chinese angelica, large-head atractylodes rhizome, Indian bread, and zingiber) drugs. In this study, we assumed these drugs have protective effects against cerebral ischemia, on neurovascular units. Houshiheisan was intragastrically administered in a rat model of focal cerebral ischemia. Hematoxylin-eosin staining, transmission electron microscopy, immunofluorescence staining, and western blot assays showed that Houshiheisan reduced pathological injury to the ischemic penumbra, protected neurovascular units, visibly up-regulated neuronal nuclear antigen expression, and down-regulated amyloid precursor protein and amyloid-β 42 expression. Wind-dispelling and deficiency-nourishing drugs maintained NeuN expression to varying degrees, but did not affect amyloid precursor protein or amyloid-β 42 expression in the ischemic penumbra. Our results suggest that the compound prescription Houshiheisan effectively suppresses abnormal amyloid precursor protein accumulation, reduces amyloid substance deposition, maintains stabilization of the internal environment of neurovascular units, and minimizes injury to neurovascular units in the ischemic penumbra.

Hippocampal expression of synaptic structural proteins and phosphorylated cAMP response element-binding protein in a rat model of vascular dementia induced by chronic cerebral hypoperfusion.

The present study established a rat model of vascular dementia induced by chronic cerebral hypoperfusion through permanent ligation of bilateral common carotid arteries. At 60 days after modeling, escape latency and swimming path length during hidden-platform acquisition training in Morris water maze significantly increased in the model group. In addition, the number of accurate crossings over the original platform significantly decreased, hippocampal CA1 synaptophysin and growth-associated protein 43 expression significantly decreased, cAMP response element-binding protein expression remained unchanged, and phosphorylated cAMP response element-binding protein expression significantly decreased. Results suggested that abnormal expression of hippocampal synaptic structural protein and cAMP response element-binding protein phosphorylation played a role in cognitive impairment following chronic cerebral hypoperfusion.

Investigation of Ginkgo biloba extract (EGb 761) promotes neurovascular restoration and axonal remodeling after embolic stroke in rat using magnetic resonance imaging and histopathological analysis

EGb 761 is a standardized natural extract from Ginkgo biloba leaf that has shown neuroprotective effects after ischemic stroke. This study aimed to use magnetic resonance imaging (MRI) to noninvasively evaluate whether EGb 761 promotes neurovascular restoration and axonal remodeling in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats were subjected to permanent right middle cerebral artery occlusion (MCAO) and treated with EGb 761 (60 mg/kg) or saline intragastrically once daily for 15 days starting 6 h after MCAO. Functional recovery was analyzed using beam walking test. Multi-parametric MRI was applied to examine the alterations of gray-white structures, intracranial vessels, cerebral perfusion and axonal integrity, and followed with histological studies. Furthermore, the protein expression of axonal remodeling related signaling pathways including protein kinase B (AKT)/ glycogen synthase kinase-3β (GSK-3β)/ collapsin response mediator protein 2 (CRMP2) and NogoA/NgR were detected by Western blotting analysis. Multi-parametric MRI demonstrated that EGb 761 significantly reduced infarct volume, alleviated gray and white matter damage, and enhanced collateral circulation, cerebral perfusion and axonal remodeling. Histological examinations supported the MRI results. EGb 761 treatment facilitated behavioral recovery and amplified endogenous neurogenesis. Notably, treatment with EGb 761 significantly increased the levels of p-AKT, p-GSK-3β and decreased the expression of p-CRMP2. In addition, EGb 761 treatment up-regulated the expression of growth associated protein 43 (GAP-43) and suppressed the activation of axonal growth inhibitory molecules NogoA and NgR. These findings indicated that EGb 761 enhanced neurovascular restoration, amplified endogenous neurogenesis and promoted axonal regeneration, which in concert may contribute to gray-white matter reorganization and functional outcome after stroke.

Effect of Bushen Yisui Capsule (补肾益髓胶囊) on oligodendrocyte lineage genes 1 and 2 in mice with experimental autoimmune encephalomyelitis

ObjectiveTo study the effects of Bushen Yisui Capsule (补肾益髓胶囊, BSYSC) on the oligodendrocyte lineage genes (Olig) 1 and Olig2 in C57BL/6 mice with experimental autoimmune encephalomyelitis (EAE) in order to explore the remyelination effect of BSYSC.MethodsThe mice were randomly divided into normal control (NC), EAE model (EAE-M), prednisone acetate (PA, 6 mg/kg), BSYSC high-dose (3.02 g/kg) and BSYSC low-dose (1.51 g/kg) groups. The mice were induced by immunization with myelin oligodendrocyte glycoprotein (MOG) 35-55. The neurological function scores were assessed once daily. The pathological changes in mice brains were observed with hematoxylin-eosin (HE) staining and transmission electron microscope (TEM). The protein expressions of myelin basic protein (MBP), Olig1 and Olig2 in brains were measured by immunohistochemistry. The mRNA expressions of Olig1 and Olig 2 was also determined by quantitative real-time polymerase chain reaction.ResultsCompared with the EAE-M mice, (1) the neurological function scores were significantly decreased in BSYSC-treated mice on days 22 to 40 (P<0.01); (2) the inflammatory cells and demyelination in brains were reduced in BSYSC-treated EAE mice; (3) the protein expression of MBP was markedly increased in BSYSC-treated groups on day 18 and 40 respectively (P<0.05 or P<0.01); (4) the protein expression of Olig1 was increased in BSYSC (3.02 g/kg)-treated EAE mice on day 40 (P<0.01). Protein and mRNA expression of Olig2 was increased in BSYSC-treated EAE mice on day 18 and 40 (P<0.01).ConclusionThe effects of BSYSC on reducing demyelination and promoting remyelination might be associated with the increase of Olig1 and Olig2.

Xiaoshuan enteric-coated capsule alleviates cognitive impairment by enhancing hippocampal glucose metabolism, hemodynamics and neuroplasticity of rat with chronic cerebral hypoperfusion.

Chronic cerebral hypoperfusion (CCH) is identified as a critical risk factor of dementia in patients with cerebrovascular disease. Xiaoshuan enteric-coated capsule (XSECC) is a compound Chinese medicine approved by Chinese State Food and Drug Administration for promoting brain remodeling and plasticity after stroke. The present study aimed to explore the potential of XSECC to improve cognitive function after CCH and further investigate the underlying mechanisms. CCH was induced by bilateral common carotid artery occlusion (BCCAO) in rats. XSECC (420 or 140 mg/kg) treatment remarkably reversed BCCAO-induced cognitive deficits. Notably, after XSECC treatment, magnetic resonance angiography combined with arterial spin labeling noninvasively demonstrated significantly improved hippocampal hemodynamics, and 18F-FDG PET/CT showed enhanced hippocampal glucose metabolism. In addition, XSECC treatment markedly alleviated neuropathologies and improved neuroplasticity in the hippocampus. More importantly, XSECC treatment facilitated axonal remodeling by regulating the phosphorylation of axonal growth related proteins including protein kinase B (AKT), glycogen synthase kinase-3β (GSK-3β) and collapsin response mediator protein-2 (CRMP2) in the hippocampus. Taken together, the present study demonstrated the beneficial role of XSECC in alleviating BCCAO-induced cognitive deficits by enhancing hippocampal glucose metabolism, hemodynamics and neuroplasticity, suggesting that XSECC could be a useful strategy in cerebral hypoperfusion state and dementia.