Ginsenoside Rg1 Exerts Anti-inflammatory Effects via G Protein-Coupled Estrogen Receptor in Lipopolysaccharide-Induced Microglia Activation.

Neuroinflammation plays a pivotal role in the pathogenesis of Parkinson's disease. Ginsenoside Rg1, the most active ingredient of ginseng, has been reported to exert neuroprotective effects via estrogen and glucocorticoid receptors. The present study evaluated the involvement of the G protein-coupled estrogen receptor (GPER) in the anti-inflammatory effects of ginsenoside Rg1 against lipopolysaccharide (LPS)-induced microglia activation in the BV2 microglial cell line and ventral mesencephalic primary microglial culture. The pharmacological blockade and lentivirus-mediated small interfering RNA (siRNA) knockdown of GPER were used to study the underlying mechanism. Rg1 attenuated LPS-induced upregulation of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) mRNA and protein levels. The GPER antagonist G15 blocked the inhibitory effects of Rg1 and the GPER-specific agonist G1 on LPS-induced microglia activation. Rg1 mimicked the effects of G1 by inhibiting the LPS-induced activation of nuclear transcription factor-kappa B (NF-κB) and mitogen activated protein kinase signaling pathways, which was also blocked by G15. Moreover, lentivirus-mediated siRNA knockdown of GPER inhibited the anti-inflammatory effects of Rg1. Taken together, our results indicate that GPER is involved in the anti-inflammatory effects of Rg1 against LPS-induced microglia activation. These findings provide a new biological target of Rg1 for the treatment of neuroinflammatory disorders.

Neuroprotective properties of icariin in MPTP-induced mouse model of Parkinson's disease: Involvement of PI3K/Akt and MEK/ERK signaling pathways.

BACKGROUND: Epimedium sagittatum is a traditional Chinese herb normally which is used to treat the osteoporosis, cardiovascular dysfunction, and to improve neurological and sexual function in China, Korea and Japan. Icariin is the major active ingredient in Epimedium sagittatum. In the present research, we examined the neuroprotective effects of icariin on dopaminergic neurons and the possible mechanisms in a mouse model of Parkinson's disease (PD). METHODS: Ovariectomized PD mice were treated with vehicle or icariin (3 days before MPTP injections) with or without the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 or mitogen-activated protein kinase kinase (MEK) inhibitor PD98059. The dopamine (DA) content in the striatum was studied by HPLC. Western blot was used to determine the protein expressions of Bcl-2, Bax and Caspase 3 in the striatum. The numbers of tyrosine hydroxylase-immunoreactive (TH-IR) neurons in the substantial nigra pars compacta (SNpc) were assessed by immunohistochemistry. The activation of Akt and ERK by icariin were detected in doparminergic MES23.5 cells. RESULTS: Icariin pretreatment could ameliorate the decreased striatum DA content and the loss of TH-IR neurons in the SNpc induced by MPTP. The MPTP-induced changes of Bcl-2, Bax and caspase 3 protein expressions in the striatum could be reversed by icariin pretreatment. Blockade of PI3K/Akt or MEK/ERK signaling pathway by LY294002 or PD98059 could attenuate the increase of DA content in the striatum and TH-IR in the SNpc induced by icariin in PD mice model. Additionally, icariin treatment alone significantly induced the phosphorylation of Akt and ERK in a time dependent pattern in dopaminergic MES 23.5 cells. These effects were abolished by co-treatment with LY294002 or PD98059. CONCLUSION: These data demonstrated that icariin has neuroprotective effect on dopaminergic neurons in PD mice model and the potential mechanisms might be related to PI3K/Akt and MEK/ERK pathways.

Association of AKT1 gene polymorphisms with sporadic Parkinson's disease in Chinese Han population.

Genetic variants of AKT1 have been shown to influence brain function of Parkinson's disease (PD) patients, and in this paper our aim is to investigate the association between the three single-nucleotide polymorphisms (rs2498799; rs2494732; rs1130214) and PD in Han Chinese. 413 Han Chinese PD patients and 450 healthy age and gender-matched controls were genotyped using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. Both the patient and control groups show similar genotype frequencies at the three loci: rs2498799, rs2494732 and rs1130214. We are able to identify a significant difference in the frequencies of genotype (p=0.019) and G allele (OR=0.764, 95% CI=0.587-0.995, p=0.045) both at rs2498799 between the patient and control groups. Furthermore, the association of subjects with GG genotypes versus those with GA+AA genotype remain significant after adjusting for age in the Han Chinese female cohort (OR=0.538, 95%CI=0.345-0.841, p=0.006), which is especially evident in the late-onset cohort (OR=0.521, 95%CI=0.309-0.877, p=0.012). In contrast, allele frequencies at rs2494732 and rs1130214 were similar between patients and controls in all subgroup analyses. These results suggest that polymorphism of AKT1 locus is associated with risk of PD and that the G allele at rs2498799 may decrease the risk of PD in the North-eastern part of Han Chinese female population.

Multiple administrations of human marrow stromal cells through cerebrospinal fluid prolong survival in a transgenic mouse model of amyotrophic lateral sclerosis.

BACKGROUND AIMS: The blood-brain barrier (BBB) is the main obstacle to cell therapy for neurologic disorders such as amyotrophic lateral sclerosis (ALS). Intrathecal injection is a potential method for cell transplantation because it would bypass the BBB. We investigated the effects of human marrow stromal cells (hMSC) delivered through cerebrospinal fluid (CSF) in a transgenic mouse model of ALS. METHODS: 5 x 10(5) hMSC were delivered into the CSF of SOD1 transgenic mice at the age of 8 weeks (single transplantation group) or 8, 10 and 12 weeks (multiple transplantation group). Clinical observation, weight, hanging wire test and motor neuron count were used to assess the disease progression in the SOD1 mice. Immunohistochemistry was performed with human-specific antibody against HuNu to examine the distribution of hMSC in the lumbar spinal cord parenchyma of SOD1 mice at the age of 15 weeks. RESULTS: Single transplantation of hMSC did not have a beneficial effect in SOD1 mice. Multiple transplantations of hMSC attenuated weight loss, enhanced motor performance, decreased motor neuron loss and, importantly, increased survival in SOD1 transgenic mice. However, only a few hMSC delivered through the CSF migrated into the lumbar spinal cord parenchyma of SOD1 mice. CONCLUSIONS: Multiple administrations of hMSC through CSF may have a therapeutic effect in SOD1 mice, although limited numbers of cells migrate into the lumbar spinal cord parenchyma. It is likely that the hMSC remaining in CSF are responsible for the effect in SOD1 mice.

Clinical and genetic study of SPG6 mutation in a Chinese family with hereditary spastic paraplegia.

Mutations in the NIPA1 gene cause autosomal dominant hereditary spastic paraplegia (ADHSP). To date, little is known about the relationship between genotype-phenotype correlation. In order to examine the gene mutation associated with the genotype-phenotype of Chinese kindred with ADHSP, linkage analysis and mutation detection were performed. For affected family members, clinical analysis, electrophysiological examination and MRI of the brain and spinal cord were also performed. Every effected patient had a c316 (G106R) mutation in the NIPA1 gene. Neurophysiological examination revealed decreased amplitude of compound muscle action potentials (CMAP) from the tibial and peroneal motor nerves in most patients. Sensory nerve action potential (SNAP) from the tibialis nerve was not elicited in most patients. Central motor conduction time (CMCT) to the abductor pollicis brevis muscle (APB), first metatarsal interosseus muscle (FMI) and anterior tibial muscle (AT) were either absent or clearly prolonged in all patients. Spinal cord MRI showed different levels of atrophy in every affected individual. These lesions present an increased spot or patch signal on transverse axis T2WI and an intense signal of continual longitudinal strip on the anteroposterior axis. Our study supports that mutations in the NIPA1 gene cause ADHSP and further demonstrates genotype-phenotype correlations in SPG6.