Icariin ameliorates the cuprizone-induced demyelination associated with antioxidation and anti-inflammation.

The treatment of immunomodulation in multiple sclerosis (MS) can alleviate the severity and relapses. However, it cannot improve the neurological disability of patients due to a lack of myelin protection and regeneration. Therefore, remyelinating therapies may be one of the feasible strategies that can prevent axonal degeneration and restore neurological disability. Natural product icariin (ICA) is a flavonol compound extracted from epimedium flavonoids, which has neuroprotective effects in several models of neurological diseases. Here, we attempt to explore whether ICA has the potential to treat demyelination and its possible mechanisms of action using lipopolysaccharide-treated BV2 microglia, primary microglia, bone marrow-derived macrophages, and cuprizone-induced demyelination model. The indicators of oxidative stress and inflammatory response were evaluated using commercial kits. The results showed that ICA significantly reduced the levels of oxidative intermediates nitric oxide, hydrogen peroxide, malondialdehyde, and inflammatory cytokines TNF-α, IL-1ß, and increased the levels of antioxidants superoxide dismutase, catalase, glutathione peroxidase, and anti-inflammatory cytokines IL-10 and TGF-ß in vitro cell experiments. In vivo demyelination model, ICA significantly alleviated the behavioral abnormalities and enhanced the integrated optical density/mm2 of Black Gold II and myelin basic protein myelin staining, accompanied by the inhibition of oxidative stress/inflammatory response. Immunohistochemical staining showed that ICA significantly induced the expression of nuclear factor erythroid derived 2/heme oxygenase-1 (Nrf2/HO-1) and inhibited the expression of toll-like receptor 4/ nuclear factor kappa B (TLR4/NF-κB), which are two key signaling pathways in antioxidant and anti-inflammatory processes. Our results strongly suggest that ICA may be used as a potential agent to treat demyelination via regulating Nrf2/HO-1-mediated antioxidative stress and TLR4/NF-κB-mediated inflammatory responses.

[Tetramethylpyrazine regulates angiogenesis of endothelial cells in cerebral ischemic stroke injury via SIRT1/VEGFA signaling pathway].

This study aims to investigate whether tetramethylpyrazine(TMP) can stimulate angiogenesis in cerebral microvascular endothelial cells and alleviate cerebral ischemic stroke(CIS) and to explore the underlying mechanisms. In the animal study, adult Sprague-Dawley rats(n=15) were assigned into sham surgery(sham), middle cerebral artery occlusion/reperfusion(MCAO/R), and MCAO/R+TMP(intraperitoneal injection of 20 mg·kg~(-1)) groups. The neurological function was evaluated by the Z-Longa method. The cerebral infarction volume was detected by TTC staining. Enzyme-linked immunosorbent assay(ELISA) was employed to detect the expression of vascular endothelial growth factor(VEGF), angiopoietin(Ang), and platelet-derived growth factor(PDGF). Immunofluorescence staining was employed to detect Ki67 and the expression of vascular endothelial growth factor A(VEGFA) and slient information regulator 1(SIRT1). Western blot was employed to determine the expression levels of VEGFA, SIRT1, angiopoietin-2(Ang-2), and platelet-derived growth factor B(PDGFB). In the cell study, mouse brain-derived endothelial cells(Bend.3) were cultured, and the optimal concentration of TMP was determined. Then, VEGF, Ang, and PDGF were detected by ELISA after the addition of cabozantinib. Western blot was employed to measure the expression of VEGFA, Ang-2, and PDGFB. Immunofluorescence staining was used to detect CD31, CD34, and Ki67, and the proliferation, migration, and tube formation ability of Bend.3 cells were observed in vitro. Western blot and immunofluorescence staining were performed to measure the expression of SIRT1 and VEGFA after addition of the SIRT1-specific inhibitor selisistat(EX-527). The results showed that compared with the sham group, the MCAO/R group had severe neurological function damage, increased infarction volume, up-regulated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, and PDGFB, and down-regulated expression of Ki67 and SIRT1(P<0.01). Compared with the MCAO/R group, the MCAO/R+TMP group presented alleviated neurological function damage, reduced infarction volume, and activated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, Ki67, and SIRT1(P<0.01). The cell experiments showed that compared with the normal group, Bend.3 cells were activated by oxygen glucose deprivation/reoxygenation(OGD/R) treatment(P<0.05, P<0.01). Compared with the OGD/R group, the OGD/R+TMP group upregulated the expression levels of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, SIRT1, Ki67, CD31, and CD34, enhanced the angiogenic ability of Bend.3 cells without being inhibited by BMS or EX-527(P<0.05, P<0.01, P<0.001). The results suggest that TMP can activate the SIRT1/VEGFA signaling pathway to stimulate angiogenesis and alleviate CIS injury.

Drug-induced microglial phagocytosis in multiple sclerosis and experimental autoimmune encephalomyelitis and the underlying mechanisms.

Microglia are resident macrophages of the central nervous system (CNS). It plays a significant role in immune surveillance under physiological conditions. On stimulation by pathogens, microglia change their phenotypes, phagocytize toxic molecules, secrete pro-inflammatory/anti-inflammatory factors, promotes tissue repair, and maintain the homeostasis in CNS. Accumulation of myelin debris in multiple sclerosis (MS)/experimental autoimmune encephalomyelitis (EAE) inhibits remyelination by decreasing the phagocytosis by microglia and prevent the recovery of MS/EAE. Drug induced microglia phagocytosis could be a novel therapeutic intervention for the treatment of MS/EAE. But the abnormal phagocytosis of neurons and synapses by activated microglia will lead to neuronal damage and degeneration. It indicates that the phagocytosis of microglia has many beneficial and harmful effects in central neurodegenerative diseases. Therefore, simply promoting or inhibiting the phagocytic activity of microglia may not achieve ideal therapeutic results. However, limited reports are available to elucidate the microglia mediated phagocytosis and its underlying molecular mechanisms. On this basis, the present review describes microglia-mediated phagocytosis, drug-induced microglia phagocytosis, molecular mechanism, and novel approach for MS/EAE treatment.

Wuzi Yanzong pill attenuates MPTP-induced Parkinson's Disease via PI3K/Akt signaling pathway.

Wuzi Yanzong Pill (WYP) was found to play a protective role on nerve cells and neurological diseases, however the molecular mechanism is unclear. To understand the molecular mechanisms that underly the neuroprotective effect of WYP on dopaminergic neurons in Parkinson's disease (PD). PD mouse model was induced by the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Gait and hanging tests were used to assess motor behavioral function. Immunofluorescence assay was used to determine TH-positive neurons in substantia nigra (SN). Apoptosis, dopamine and neurotrophic factors as well as expression of PI3K/Akt pathway were detected by TUNEL staining, ELISA and western blotting, respectively. First, it was observed that WYP intervention improved abnormal motor function in MPTP-induced PD model, alleviated the loss of TH+ neurons in SN, and increased dopamine content in brain, revealing a potential protective effect. Second, network pharmacology was used to analyze the possible targets and pathways of WYP action in the treatment of PD. A total of 126 active components related to PD were screened in WYP, and the related core targets included ALB, GAPDH, Akt1, TP53, IL6 and TNF. Particularly, the effect of WYP on PD may be medicate through PI3K/Akt signaling pathway and apoptotic regulation. The WYP treated PD mice had higher expression of p-PI3K, p-Akt and Bcl-2 but lower expression of Bax and cleaved caspase-3 than the non-WYP treated PD mice. Secretion of brain-derived neurotrophic factor (BDNF) and cerebral dopamine neurotrophic factor (CDNF) were also increased in the treated mice. WYP may inhibit apoptosis and increase the secretion of neurotrophic factor via activating PI3K/ Akt signaling pathway, thus protecting the loss of dopamine neurons in MPTP-induced PD mice.

Targeting the differentiation of astrocytes by Bilobalide in the treatment of Parkinson's disease model.

Background: The etiology of Parkinson's disease (PD), a chronic and progressive neurodegenerative disease, is multifactorial but not fully unknown. Until now, no drug has been proven to have neuroprotective or neuroregenerative effects in patients with PD.Objectives: To observe the therapeutic potential of Bilobalide (BB), a constituent of ginkgo biloba, in MPTP-induced PD model, and explore its possible mechanisms of action.Material and Methods: Mice were randomly divided into three groups: healthy group, MPTP group and MPTP + BB group. PD-related phenotypes were induced by intraperitoneal injection of MPTP into male C57BL/6 mice, and BB (40 mg/kg/day) was intraperitoneally given for 7 consecutive days at the end of modeling. The injection of saline was set up as the control in a similar manner.Results: BB induced M2 polarization of microglia, accompanied by inhibition of neuroinflammation in the brain. Simultaneously, BB promoted the expression of BDNF in astrocytes and neurons, and expression of GDNF in neurons. Most interestingly, BB enhanced the formation of GFAP+ astrocytes expressing nestin, Brn2 and Ki67, as well as the transformation of GFAP+ astrocytes expressing tyrosine hydroxylase around subventricular zone, providing experimental evidence that BB could promote the conversion of astrocytes into TH+ dopamine neurons in vivo and in vitro.Conclusions: These results suggest the natural product BB may utilize multiple pathways to modify degenerative process of TH+ neurons, revealing an exciting opportunity for novel neuroprotective therapeutics. However, its multi-target and important mechanisms need to be further explored.

Temporal and spatial evolution of various functional neurons during demyelination induced by cuprizone.

Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system (CNS). Here we report the temporal and spatial evolution of various functional neurons during demyelination in a cuprizone (CPZ)-induced mouse model. CPZ did not significantly induce the damage of axons and neurons after 2 wk of feeding. However, after 4-6 wk of CPZ feeding, axons and neurons were markedly reduced in the cortex, posterior thalamic nuclear group, and hippocampus. Simultaneously, the expression of TPH+ tryptophan neurons and VGLUT1+ glutamate neurons was obviously decreased, and the expression of TH+ dopaminergic neurons was slightly decreased in the tail part of the substantia nigra striatum, whereas the number of ChAT+ cholinergic neurons was not significantly different in the brain. In the second week of feeding, CPZ caused a higher level of glutamate secretion and upregulated the expression of EAAT2 on astrocytes, which should contribute to rapid and sufficient glutamate uptake and removal. This finding reveals that astrocyte-driven glutamate reuptake protected the CNS from excitotoxicity by rapid reuptake of glutamate in 4-6 wk of CPZ feeding. At this stage, although NG2+ oligodendroglia progenitor cells (OPCs) were enhanced in the demyelination foci, the myelin sheath was still absent. In conclusion, we comprehensively observed the temporal and spatial evolution of various functional neurons. Our results will assist with understanding how demyelination affects neurons during CPZ-induced demyelination and provide novel information for neuroprotection in myelin regeneration and demyelinating diseases.NEW & NOTEWORTHY Our results further indicate temporal and spatial evolution of various functional neurons during the demyelination in a cuprizone (CPZ)-induced mouse model, which mainly occur 4-6 wk after CPZ feeding. At the same time, the axonal compartment is damaged and, consequently, neuronal death occurs, while glutamate neurons are lost obviously. The astrocyte-mediated glutamate reuptake could protect the neurons from the excitatory effects of glutamate.

Fasudil reduces ß-amyloid levels and neuronal apoptosis in APP/PS1 transgenic mice via inhibition of the Nogo-A/NgR/RhoA signaling axis.

Recent studies have shown that Nogo-A and the Nogo-A receptor affect ß-amyloid metabolism and the downstream Rho GTP enzyme signaling pathway, which may affect the levels of ß-amyloid and tau. Nogo-A may play a key role in the pathogenesis of Alzheimer's disease. However, the underlying molecular mechanisms of Fasudil treatment in Alzheimer's disease are not yet clear. Our results have found that Fasudil treatment for two months substantially ameliorated behavioral deficits, diminished ß-amyloid plaque and tau protein pathology, and alleviated neuronal apoptosis in APP/PS1 transgenic mice. More importantly, two well-established markers for synaptic function, growth-associated protein 43 and synaptophysin, were upregulated after Fasudil treatment. Finally, the levels of Nogo-A, Nogo-A receptor complex NgR/p75NTR/LINGO-1 and the downstream Rho/Rho kinase signaling pathway were significantly reduced. These findings suggest that Fasudil exerts its neuroprotective function in Alzheimer's disease by inhibiting the Nogo-A/NgR1/RhoA signaling pathway.

Hydroxyfasudil alleviates demyelination through the inhibition of MOG antibody and microglia activation in cuprizone mouse model.

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system characterized by oligodendrocyte loss and progressive neurodegeneration. The cuprizone (CPZ)-induced demyelination is widely used to investigate the demyelination/remyelination. Here, we explored the therapeutic effects of Hydroxyfasudil (HF), an active metabolite of Fasudil, in CPZ model. HF improved behavioral abnormality and reduced myelin damage in the corpus callosum. Splenic atrophy and myelin oligodendrocyte glycoprotein (MOG) antibody were observed in CPZ model, which were partially restored and obviously inhibited by HF, therefore reducing pathogenic binding of MOG antibody to oligodendrocytes. HF inhibited the percentages of CD4+IL-17+ T cells from splenocytes and infiltration of CD4+ T cells and CD68+ macrophages in the brain. HF also declined microglia-mediated neuroinflammation, and promoted the production of astrocyte-derived brain derived neurotrophic factor (BDNF) and regeneration of NG2+ oligodendrocyte precursor cells. These results provide potent evidence for the therapeutic effects of HF in CPZ-induced demyelination.

The Rho kinase inhibitor fasudil attenuates Aß1-42-induced apoptosis via the ASK1/JNK signal pathway in primary cultures of hippocampal neurons.

Alzheimer's disease (AD), a chronic, progressive, neurodegenerative disorder, is the most common type of dementia. Beta amyloid (Aß) peptide aggregation and phosphorylated tau protein accumulation are considered as one of the causes for AD. Our previous studies have demonstrated the neuroprotective effect of the Rho kinase inhibitor fasudil, but the mechanism remains elucidated. In the present study, we examined the effects of fasudil on Aß1-42 aggregation and apoptosis and identified the intracellular signaling pathways involved in these actions in primary cultures of mouse hippocampal neurons. The results showed that fasudil increased neurite outgrowth (52.84%), decreased Aß burden (46.65%), Tau phosphorylation (96.84%), and ROCK-II expression. In addition, fasudil reversed Aß1-42-induced decreased expression of Bcl-2 and increases in caspase-3, cleaved-PARP, phospho-JNK(Thr183/Tyr185), and phospho-ASK1(Ser966). Further, fasudil decreased mitochondrial membrane potential and intracellular calcium overload in the neurons treated with Aß1-42. These results suggest that inhibition of Rho kinase by fasudil reverses Aß1-42-induced neuronal apoptosis via the ASK1/JNK signal pathway, calcium ions, and mitochondrial membrane potential. Fasudil could be a drug of choice for treatment of Alzheimer's disease.

Ir-Catalyzed Regio- and Stereoselective Hydrosilylation of Internal Thioalkynes: A Combined Experimental and Computational Study.

Iridium complexes are known catalysts for a range of silylation reactions. However, the exploitation for selective hydrosilylation of unsymmetrical internal alkynes has been limitedly known. Described here is a new example of this type. Specifically, [(cod)IrCl]2 catalyzes the efficient and mild hydrosilylation of thioalkynes by various silanes with excellent regio- and stereoselectivity. DFT studies suggested a new mechanism involving Ir(I) hydride as the key intermediate.

Metal-Free [2+2+2] Cycloaddition of Ynamides and Nitriles: Mild and Regioselective Synthesis of Fully Substituted Pyridines.

A metal-free trimolecular [2+2+2] cycloaddition of internal ynamides and nitriles for de novo synthesis of fully substituted pyridines is disclosed. With the versatile Brønsted acid catalyst HNTf2 , the mild intermolecular cyclotrimerization process proceeds with complementary chemoselectivity and excellent regioselectivity.

Genetic diversity of male and female Chinese bayberry (Myrica rubra) populations and identification of sex-associated markers.

BACKGROUND: Chinese bayberry (Myrica rubra Sieb. & Zucc.) is an important subtropical evergreen fruit tree in southern China. Generally dioecious, the female plants are cultivated for fruit and have been studied extensively, but male plants have received very little attention. Knowledge of males may have a major impact on conservation and genetic improvement as well as on breeding. Using 84 polymorphic SSRs, we genotyped 213 M. rubra individuals (99 male individuals, 113 female varieties and 1 monoecious) and compared the difference in genetic diversity between the female and the male populations. RESULTS: Neighbour-joining cluster analysis separated M. rubra from three related species, and the male from female populations within M. rubra. By structure analysis, 178 M. rubra accessions were assigned to two subpopulations: Male dominated (98) and Female dominated (80). The well-known cultivars 'Biqi' and 'Dongkui', and the landraces 'Fenhong' are derived from three different gene pools. Female population had a slightly higher values of genetic diversity parameters (such as number of alleles and heterozygosity) than the male population, but not significantly different. The SSR loci ZJU062 and ZJU130 showed an empirical Fst value of 0.455 and 0.333, respectively, which are significantly above the 95 % confidence level, indicating that they are outlier loci related to sex separation. CONCLUSION: The male and female populations of Chinese bayberry have similar genetic diversity in terms of average number of alleles and level of heterozygosity, but were clearly separated by genetic structure analysis due to two markers associated with sex type, ZJU062 and ZJU130. Zhejiang Province China could be the centre of diversity of M. rubra in China, with wide genetic diversity coverage; and the two representative cultivars 'Biqi' and 'Dongkui', and one landrace 'Fenhong' in three female subpopulations. This research provides genetic information on male and female Chinese bayberry and will act as a reference for breeding programs.

[Analysis of 105 Incarcerated Inmate's Death].

OBJECTIVE: To analyze the characteristics in the incarcerated inmate's death, investigate the main cause of death of the incarcerated inmate and provide some information for forensic investigation. METHODS: The cases from the forensic medical center of Shanxi Medical University from 2005 to 2013 were selected. The statistical analysis was performed by using the incarcerated inmate's gender, age, cause of death, manner of death, and disease as the markers. RESULTS: There were 100 men, 5 women in the 105 incarcerated inmates; the age range was from 16 to 65 years; Inmates were mostly died of natural diseases, mainly in the respiratory and cardiovascular diseases; the main unnatural death was suicide with a rate of 54.5%. CONCLUSION: At present, most incarcerated inmate's death are due to natural diseases. The prison should improve incarcerated inmate's lives, work and health care conditions, and strengthen supervision of law enforcement.

Highly Regio- and Stereoselective Hydrosilylation of Internal Thioalkynes under Mild Conditions.

A general and mild hydrosilylation of thioalkynes is described. With the cationic catalyst [Cp*Ru(MeCN)3 ](+) and the bulky silane (TMSO)3 SiH, a range of thioalkynes underwent smooth hydrosilylation at room temperature with excellent α regioselectivity and syn stereoselectivity. DFT calculations provided important insight into the mechanism, particularly the unusual syn selectivity with the [Cp*Ru(MeCN)3 ](+) catalyst. The sulfenyl group in the substrates was found to provide important chelation stabilization to direct the reaction through a new mechanistic pathway.

Ligand-controlled remarkable regio- and stereodivergence in intermolecular hydrosilylation of internal alkynes: experimental and theoretical studies.

The first highly efficient ligand-controlled regio- and stereodivergent intermolecular hydrosilylations of internal alkynes have been disclosed. Cationic ruthenium complexes [Cp*Ru(MeCN)3](+) and [CpRu(MeCN)3](+) have been demonstrated to catalyze intermolecular hydrosilylations of silyl alkynes to form a range of vinyldisilanes with excellent but opposite regio- and stereoselectivity, with the former being α anti addition and the latter ß syn addition. The use of a silyl masking group not only provides sufficient steric bulk for high selectivity but also leads to versatile product derivatizations toward a variety of useful building blocks. DFT calculations suggest that the reactions proceed by a mechanism that involves oxidative hydrometalation, isomerization, and reductive silyl migration. The energetics of the transition states and intermediates varies dramatically with the catalyst ligand (Cp* and Cp). Theoretical studies combined with experimental evidence confirm that steric effect plays a critical role in governing the regio- and stereoselectivity, and the interplay between the substituent in the alkyne (e.g., silyl group) and the ligand ultimately determines the observed remarkable regio- and stereodivergence.

The effects and potential of microglial polarization and crosstalk with other cells of the central nervous system in the treatment of Alzheimer's disease.

Microglia are resident immune cells in the central nervous system. During the pathogenesis of Alzheimer's disease, stimulatory factors continuously act on the microglia causing abnormal activation and unbalanced phenotypic changes; these events have become a significant and promising area of research. In this review, we summarize the effects of microglial polarization and crosstalk with other cells in the central nervous system in the treatment of Alzheimer's disease. Our literature search found that phenotypic changes occur continuously in Alzheimer's disease and that microglia exhibit extensive crosstalk with astrocytes, oligodendrocytes, neurons, and penetrated peripheral innate immune cells via specific signaling pathways and cytokines. Collectively, unlike previous efforts to modulate microglial phenotypes at a single level, targeting the phenotypes of microglia and the crosstalk with other cells in the central nervous system may be more effective in reducing inflammation in the central nervous system in Alzheimer's disease. This would establish a theoretical basis for reducing neuronal death from central nervous system inflammation and provide an appropriate environment to promote neuronal regeneration in the treatment of Alzheimer's disease.

Fasudil alleviates cerebral ischemia­reperfusion injury by inhibiting inflammation and improving neurotrophic factor expression in rats.

The Rho kinase inhibitor fasudil exerts neuroprotective effects. We previously showed that fasudil can regulate M1/M2 microglia polarization and inhibit neuroinflammation. Here, the therapeutic effect of fasudil on cerebral ischemia­reperfusion (I/R) injury was investigated using the middle cerebral artery occlusion and reperfusion (MCAO/R) model in Sprague­Dawley rats. The effect of fasudil on the phenotype of microglia and neurotrophic factors in the I/R brain and its potential molecular mechanism was also explored. It was found that fasudil ameliorated neurological deficits, neuronal apoptosis, and inflammatory response in rats with cerebral I/R injury. Fasudil also promoted the polarization of microglia into the M2 phenotype, in turn promoting the secretion of neurotrophic factors. Furthermore, fasudil significantly inhibited the expression of TLR4 and NF­κB. These findings suggest that fasudil could inhibit the neuroinflammatory response and reduce brain injury after I/R injury by regulating the shift of microglia from an inflammatory M1 phenotype to an anti­inflammatory M2 phenotype, which may be related to the regulation of the TLR4/ NF­κB signal pathway.