Effects of Bu Shen Yi sui capsule on NogoA/NgR and its signaling pathways RhoA/ROCK in mice with experimental autoimmune encephalomyelitis

Buyang Huanwu Decoction promotes neurovascular remodeling by modulating astrocyte and microglia polarization in ischemic stroke rats

ETHNOPHARMACOLOGICAL RELEVANCE

Buyang Huanwu Decoction (BYHWD), one of the most commonly utilized traditional Chinese medicine prescription for treatment of cerebral ischemic stroke. However, the understanding of BYHWD on neurovascular repair following cerebral ischemia is so far limited.

AIM OF THE STUDY

This research investigated the influence of BYHWD on neurovascular remodeling by magnetic resonance imaging (MRI) technology and revealed the potential neurovascular repair mechanism underlying post-treatment with BYHWD after ischemic stroke.

MATERIALS AND METHODS

Male Sprague-Dawley rats were utilized as an ischemic stroke model by permanent occlusion of the middle cerebral artery (MCAO). BYHWD was intragastrically administrated once daily for 30 days straight. Multimodal MRI was performed to detect brain tissue injuries, axonal microstructural damages, cerebral blood flow and intracranial vessels on the 30th day after BYHWD treatment. Proangiogenic factors, axonal/synaptic plasticity-related factors, energy transporters and adenosine monophosphate-activated protein kinase (AMPK) signal pathway were evaluated using western blot. Double immunofluorescent staining and western blot were applied to evaluate astrocytes and microglia polarization.

RESULTS

Administration of BYHWD significantly alleviated infarct volume and brain tissue injuries and ameliorated microstructural damages, accompanied with improved axonal/synaptic plasticity-related factors, axonal growth guidance factors and decreased axonal growth inhibitors. Meanwhile, BYHWD remarkably improved cerebral blood flow, cerebral vascular signal and promoted the expression of proangiogenic factors. Particularly, treatment with BYHWD obviously suppressed astrocytes A1 and microglia M1 polarization accompanied with promoted astrocyte A2 and microglia M2 polarization. Furthermore, BYHWD effectively improved energy transporters. Especially, BYHWD markedly increased expression of phosphorylated AMPK, cyclic AMP-response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) accompanied by inactivation of the NF-κB.

CONCLUSION

Taken together, these findings identified that the beneficial roles of BYHWD on neurovascular remodeling were related to AMPK pathways -mediated energy transporters and NFκB/CREB pathways.

Inhibition of RhoA/ROCK signalling pathway activity improves neural damage and cognitive deficits in the fluorosis model

Excessive fluoride intake poses health risks to humans and animals. Many studies have indicated that fluoride exposure can damage the cytoskeleton and synapses, which has negative effects on the intellectual development of humans and animals. Our previous study suggested that the RhoA/ROCK signalling pathway is activated by NaF exposure in HT-22 cells and plays a vital role in cytoskeletal assembly and synaptogenesis. However, the mechanism underlying RhoA/ROCK-mediated cytoskeletal injury induced by fluoride remains unclear. In this study, Neuro-2A cells and ICR mice were used to investigate the effects of RhoA/ROCK activation inhibition on NaF-induced synaptic dysfunction and cognitive impairment. We detected the expression of GAP, RhoA, ROCK1/2, and (p)-MLC in vivo and in vitro model. The results showed that NaF exposure activated the RhoA/ROCK/MLC signalling pathway. We measured the effects of RhoA/ROCK inhibition on synaptic injury and intellectual impairment induced by NaF exposure. In vitro, Y-27632 suppressed activated RhoA/ROCK, attenuated morphological and ultrastructural damage, and decreased the survival rate and synapse-functional protein expression caused by NaF. In vivo, the results showed that the RhoA/ROCK/MLC pathway was inhibited by fasudil and improved pathological damage in the hippocampus, cognitive impairment, and decreased expression of neurofunctional proteins induced by NaF. Overall, these results suggest that fasudil and Y-27632 can reverse neurotoxicity caused by fluoride exposure. Furthermore, inhibition of RhoA/ROCK may be a future treatment for CNS injury, and more detailed studies on other neurodegenerative disease models are required to confirm its effectiveness.

5-HMF attenuates inflammation and demyelination in experimental autoimmune encephalomyelitis mice by inhibiting the MIF-CD74 interaction

The neuroprotective role of 5-hydroxymethyl-2-furfural (5-HMF) has been demonstrated in a variety of neurological diseases. The aim of this study is to investigate the effect of 5-HMF on multiple sclerosis (MS). IFN-γ-stimulated murine microglia (BV2 cells) are considered a cell model of MS. With 5-HMF treatment, microglial M1/2 polarization and cytokine levels are detected. The interaction of 5-HMF with migration inhibitory factor (MIF) is predicted using online databases. The experimental autoimmune encephalomyelitis (EAE) mouse model is established, followed by a 5-HMF injection. The results show that 5-HMF facilitates IFN-γ-stimulated microglial M2 polarization and attenuates the inflammatory response. According to the network pharmacology and molecular docking results, 5-HMF has a binding site for MIF. Further results show that blocking MIF activity or silencing CD74 enhances microglial M2 polarization, reduces inflammatory activity, and prevents ERK1/2 phosphorylation. 5-HMF inhibits the MIF-CD74 interaction by binding to MIF, thereby inhibiting microglial M1 polarization and enhancing the anti-inflammatory response. 5-HMF ameliorates EAE, inflammation, and demyelination in vivo. In conclusion, our research indicates that 5-HMF promotes microglial M2 polarization by inhibiting the MIF-CD74 interaction, thereby attenuating inflammation and demyelination in EAE mice.

Advantages of Rho-associated kinases and their inhibitor fasudil for the treatment of neurodegenerative diseases

Ras homolog (Rho)-associated kinases (ROCKs) belong to the serine-threonine kinase family, which plays a pivotal role in regulating the damage, survival, axon guidance, and regeneration of neurons. ROCKs are also involved in the biological effects of immune cells and glial cells, as well as the development of neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Previous studies by us and others confirmed that ROCKs inhibitors attenuated the symptoms and progression of experimental models of the abovementioned neurodegenerative diseases by inhibiting neuroinflammation, regulating immune imbalance, repairing the blood-brain barrier, and promoting nerve repair and myelin regeneration. Fasudil, the first ROCKs inhibitor to be used clinically, has a good therapeutic effect on neurodegenerative diseases. Fasudil increases the activity of neural stem cells and mesenchymal stem cells, thus optimizing cell therapy. This review will systematically describe, for the first time, the effects of abnormal activation of ROCKs on T cells, B cells, microglia, astrocytes, oligodendrocytes, and pericytes in neurodegenerative diseases of the central nervous system, summarize the therapeutic potential of fasudil in several experimental models of neurodegenerative diseases, and clarify the possible cellular and molecular mechanisms of ROCKs inhibition. This review also proposes that fasudil is a novel potential treatment, especially in combination with cell-based therapy. Findings from this review add support for further investigation of ROCKs and its inhibitor fasudil for the treatment of neurodegenerative diseases.

Exosomes: A novel insight into traditional Chinese medicine

Exosomes are small extracellular vesicles and play an essential role in the mediation of intercellular communication both in health and disease. Traditional Chinese medicine (TCM) has historically been used to maintain human health and treat various diseases up till today. The interplay between exosomes and TCM has attracted researchers’ growing attention. By integrating the available evidence, TCM formulas and compounds isolated from TCM as exosome modulators have beneficial effects on multiple disorders, such as tumors, kidney diseases, and hepatic disease, which may associate with inhibiting cells proliferation, anti-inflammation, anti-oxidation, and attenuating fibrosis. Exosomes, a natural delivery system, are essential in delivering compounds isolated from TCM to target cells or tissues. Moreover, exosomes may be the potential biomarkers for TCM syndromes, providing strategies for TCM treatment. These findings may provide a novel insight into TCM from exosomes and serve as evidence for better understanding and development of TCM.

Study on the Anti-demyelination Mechanism of Bu-Shen-Yi-Sui Capsule in the Central Nervous System Based on Network Pharmacology and Experimental Verification

Methods

The potential active ingredients and corresponding potential targets of BSYS Capsule were obtained from the TCMSP, BATMAN-TCM, Swiss Target Prediction platform, and literature research. Disease targets of CNSD were explored through the GeneCards and the DisGeNET databases. The matching targets of BSYS in CNSD were identified from a Venn diagram. The protein-protein interaction (PPI) network was constructed using bioinformatics methods. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to predict the mechanisms of BSYS. Furthermore, the neuroprotective effects of BSYS were evaluated using a cell model of hydrogen peroxide- (H₂O₂-) induced cell death in OLN-93 cells.

Results

A total of 59 potential bioactive components of BSYS Capsule and 227 intersection targets were obtained. Topological analysis showed that AKT had the highest connectivity degrees in the PPI network. Enrichment analysis revealed that the targets of BSYS in the treatment of CNSD were the PI3K-Akt and MAPK signaling pathway, among other pathways. GO analysis results showed that the targets were associated with various biological processes, including apoptosis, reactive oxygen species metabolic process, and response to oxidative stress, among others. The experimental results demonstrated that BSYS drug-containing serum alleviated the H₂O₂-induced increase in LDH, MDA, and ROS levels and reversed the decrease in SOD and mitochondrial membrane potential induced by H₂O₂. BSYS treatment also decreased the number of TUNEL (+) cells, downregulated Bcl-2 expression, and upregulated Bax and c-caspase-3 expression by promoting Akt phosphorylation.

Conclusion

BSYS Capsule alleviated H₂O₂-induced OLN-93 cell injury by increasing Akt phosphorylation to suppress oxidative stress and cell apoptosis. Therefore, BSYS can be potentially used for CNSD treatment. However, the results of this study are only derived from in vitro experiments, lacking the validation of in vivo animal models, which is a limitation of our study. We will further verify the underlying mechanisms of BSYS in animal experiments in the future.

Bu Shen Yi Sui Capsules Promote Remyelination by Regulating MicroRNA-219 and MicroRNA-338 in Exosomes to Promote Oligodendrocyte Precursor Cell Differentiation

Remyelination is a refractory feature of demyelinating diseases such as multiple sclerosis (MS). Studies have shown that promoting oligodendrocyte precursor cell (OPC) differentiation, which cannot be achieved by currently available therapeutic agents, is the key to enhancing remyelination. Bu Shen Yi Sui capsule (BSYSC) is a traditional Chinese herbal medicine over many years of clinical practice. We have found that BSYSC can effectively treat MS. In this study, the effects of BSYSC in promoting OPCs differentiation and remyelination were assessed using an experimental autoimmune encephalomyelitis (EAE) model in vivo and cultured OPCs in vitro. The results showed that BSYSC reduced clinical function scores and increased neuroprotection. The expression of platelet-derived growth factor receptor α (PDGFR-α) was decreased and the level of 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNPase) was increased in the brains and spinal cords of mice as well as in OPCs after treatment with BSYSC. We further found that BSYSC elevated the expression of miR-219 or miR-338 in the serum exosomes of mice with EAE, thereby suppressing the expression of Sox6, Lingo1, and Hes5, which negatively regulate OPCs differentiation. Therefore, serum exosomes of BSYSC-treated mice (exos-BSYSC) were extracted and administered to OPCs in which miR-219 or miR-338 expression was knocked down by adenovirus, and the results showed that Sox6, Lingo1, and Hes5 expression was downregulated, MBP expression was upregulated, OPCs differentiation was increased, and the ability of OPCs to wrap around neuronal axons was improved. In conclusion, BSYSC may exert clinically relevant effects by regulating microRNA (miR) levels in exosomes and thus promoting the differentiation and maturation of OPCs.

Xuesaitong exerts long-term neuroprotection for stroke recovery by inhibiting the ROCKII pathway, in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Xuesaitong (XST) is a traditional Chinese medicine injection with neuroprotective properties and has been extensively used to treat stroke for many years. The main component of XST is Panax notoginseng saponins (PNS), which is the main extract of the Chinese herbal medicine Panax notoginseng.

AIM OF THE STUDY

In this study, we investigated whether XST provided long-term neuroprotection by inhibiting neurite outgrowth inhibitor-A (Nogo-A) and the ROCKII pathway in experimental rats after middle cerebral artery occlusion (MCAO) and in SH-SY5Y cells exposed to oxygen-glucose deprivation/reperfusion (OGD/R).

MATERIALS AND METHODS

Rats with permanent MCAO were administered XST, Y27632, XST plus Y27632, and nimodipine for 14 and 28 days. Successful MCAO onset was confirmed by 2,3,5-triphenyl tetrazolium chloride (TTC) staining. Neurological deficit score (NDS) was used to assess neurological impairment. Hematoxylin-eosin (HE) staining and immunohistochemical (IHC) analysis of synaptophysin (SYN) and postsynaptic density protein-95 (PSD-95) were performed to evaluate cerebral ischemic injury and the neuroprotective capability of XST. Nogo-A levels and the ROCKII pathway were detected by IHC analysis, western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR) to explore the protective mechanism of XST. OGD/R model was established in SH-SY5Y cells. Cell counting kit 8 (CCK8) was applied to detect the optimum OGD time and XST concentration. The expression levels Nogo-A and ROCKII pathway were determined using western blotting.

RESULTS

Our results showed that XST reduced neurological dysfunction and pathological damage, promoted weight gain and synaptic regeneration, reduced Nogo-A mRNA and protein levels, and inhibited the ROCKII pathway in MCAO rats. CCK8 assay displayed that the optimal OGD time and optimal XST concentration were 7 h and 20 μg/mL respectively in SH-SY5Y cells. XST could evidently inhibit OGD/R-induced Nogo-A protein expression and ROCKII pathway activation in SH-SY5Y cells.

CONCLUSIONS

The present study suggested that XST exerted long-term neuroprotective effects that assisted in stroke recovery, possibly through inhibition of the ROCKII pathway.

Aerobic exercise training decreases cognitive impairment caused by demyelination by regulating ROCK signaling pathway in aging mice

Recent studies have discovered a strong link between physical exercise and the prevention of neuro-degenerative symptoms, especially in elderly subjects, nonetheless, the exact underlying mechanism remains unclear. In this study, we hypothesized that aerobic exercise training may have a protective effect on myelin sheath in aged mice by regulating the ROCK signal pathway, which is considered as a crucial mechanism for decreasing apoptosis and promoting regeneration. Briefly, C57/BL aged mice underwent an exercise training (5 days/week, lasting 6 weeks). Memory and cognitive impairment were examined using Novel object recognition (NOR) test and Morris water maze test (MWM). Demyelination was explored using Luxol fast blue staining and transmission electron microscopy in the corpus callosum (CC), and the expression of ROCK and apoptotic protein were analyzed via western blot. We demonstrated the impairment of memory and cognitive and the decrease of myelin sheath thickness in aged mice. In addition, severe demyelination was observed in aged mice, accompanied with increased expression of RhoA, ROCK, ATF3, and Caspase 3, and reduced expression of MBP, Olig2, and NG2. Aerobic exercise training improved behavioral functions, increased the expression of MBP and myelin sheath thickness, reduced apoptosis and promoted myelination. To sum up, our data indicate that aerobic exercise training protects demyelination from aging-related white matter injury, which is associated with the up-regulation of ROCK signal pathway.

Bu-Shen-Yi-Sui Capsule, an Herbal Medicine Formula, Promotes Remyelination by Modulating the Molecular Signals via Exosomes in Mice with Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a common inflammatory demyelinating disorder of the central nervous system. Bu-shen-yi-sui capsule (BSYSC) could significantly reduce the relapse rate, prevent the progression of MS, and enhance remyelination following neurological injury in experimental autoimmune encephalomyelitis (EAE), an established model of MS; however, the mechanism underlying the effect of BSYSC on remyelination has not been well elucidated. This study showed that exosomes carrying biological information are involved in the pathological process of MS and that modified exosomes can promote remyelination by modulating related proteins and microRNAs (miRs). Here, the mechanism by which BSYSC promoted remyelination via exosome-mediated molecular signals was investigated in EAE mice and oligodendrocyte progenitor cells (OPCs) in vitro. The results showed that BSYSC treatment significantly improved the body weight and clinical scores of EAE mice, alleviated inflammatory infiltration and nerve fiber injury, protected the ultrastructural integrity of the myelin sheath, and significantly increased the expression of myelin basic protein (MBP) in EAE mice. In an in vitro OPC study, BSYSC-containing serum, especially 20% BSYSC, promoted the proliferation and migration of OPCs and induced OPCs to differentiate into mature oligodendrocytes that expressed MBP. Furthermore, BSYSC treatment regulated the expression of neuropilin- (NRP-) 1 and GTX, downregulated the expression of miR-16, let-7, miR-15, miR-98, miR-486, and miR-182, and upregulated the level of miR-146 in serum exosomes of EAE mice. In conclusion, these results suggested that BSYSC has a neuroprotective effect and facilitates remyelination and that the mechanism underlying the effect of BSYSC on remyelination probably involves regulation of the NRP-1 and GTX proteins and miRs in serum exosomes, which drive promyelination.

The Bu Shen Yi Sui Formula Promotes Axonal Regeneration via Regulating the Neurotrophic Factor BDNF/TrkB and the Downstream PI3K/Akt Signaling Pathway

Axonal damage is recognized as an important pathological feature in the chronic progressive neurological disorder multiple sclerosis (MS). Promoting axonal regeneration is a critical strategy for the treatment of MS. Our clinical and experimental studies have shown that the Bu Shen Yi Sui formula (BSYS) promotes axonal regeneration in MS and experimental autoimmune encephalomyelitis (EAE), an animal model of MS, but the exact mechanism has not been thoroughly elucidated to date. In this study, we investigated the effects of BSYS and its two decomposed formulas-the Bu Shen formula (BS) and the Hua Tan Huo Xue formula (HTHX)-on brain-derived neurotrophic factor (BDNF)/TrkB and related signaling pathways to explore the mechanism by which axonal regeneration is promoted in vitro and in vivo. Damaged SH-SY5Y cells incubated with low serum were treated with BSYS-, BS-, and HTHX-containing serum, and EAE mice induced by the myelin oligodendrocyte glycoprotein (MOG)_35-55 peptide were treated with BSYS. The results showed that the BSYS-containing serum markedly increased cell viability and increased the levels of growth associated protein (GAP)-43, phosphorylated (p)-cAMP-response element binding protein (CREB), BDNF, TrkB, and p-PI3K. The BS and HTHX treatments also induced the protein expression of GAP-43 and p-extracellular signal-regulated kinase (ERK) in the cells. Furthermore, the effects of BSYS on cell viability, GAP-43, p-CREB, and neurite outgrowth were clearly inhibited by LY294002, a specific antagonist of the PI3K signaling pathways. The addition of U0126 and U73122, antagonists of the ERK and PLCγ pathway, respectively, significantly inhibited cell viability and GAP-43 protein expression. Moreover, BSYS treatment significantly increased the expression of the 68-, 160-, and 200-kDa neurofilaments (NFs) of proteins and the BDNF, TrkB, PI3K, and Akt mRNA and proteins in the brain or spinal cord of mice at different stages. These results indicated that BSYS promotes nerve regeneration, and its mechanism is mainly related to the upregulation of the BDNF/TrkB and PI3K/Akt signaling pathways. BS and HTHX also promoted nerve regeneration, and this effect involved the ERK pathway.

Bu Shen Yi Sui capsule promotes remyelination correlating with Sema3A/NRP-1, LIF/LIFR and Nkx6.2 in mice with experimental autoimmune encephalomyelitis

ETHNOPHARMACOLOGICAL RELEVANCE

Bu Shen Yi Sui capsule (BSYSC), based on traditional Chinese formula Liu Wei Di Huang pill, is effective for the treatment of multiple sclerosis (MS) in clinical experience and trials. Our previous studies confirmed that BSYSC had the neuroprotective effect in MS and its animal model, experimental autoimmune encephalomyelitis (EAE); however, its mechanism of action was not clear. Thus, the effect of BSYSC on remyelination and the underlying mechanisms were investigated in the EAE mice.

MATERIALS AND METHODS

The EAE model was established by injecting subcutaneously myelin oligodendrocyte protein (MOG) _35-55 in mice. Mice were treated with BSYSC (3.02 g/kg) or vehicle daily by oral gavage for 40 days. The body weight and clinical score of mice were evaluated. Brain was observed by magnetic resonance imaging. The inflammation infiltrate of brain and spinal cord was determined by hematoxylin-eosin staining, while the structure of myelin sheath was visualized by transmission electron microscopy on days 23 and 40 post immunization (dpi), respectively. The protein and mRNA levels of platelets-derived growth factor receptor (PDGFR) α and 2', 3'-cyclic nucleotide-3'-phosphodiesterase (CNPase) were measured by immunohistochemistry, western blot and quantitative real-time polymerase chain reaction. The protein expressions of semaphorins (Sema) 3A, Neuropilin (NRP) - 1, leukemia inhibitory factor (LIF), LIF receptor (LIFR) and Nkx6.2 were further investigated by western blot.

RESULTS

BSYSC treatment improved the body weight and clinical score of EAE mice, alleviated inflammatory infiltration and nerve fiber injuries. It also protected the ultrastructural integrity of myelin sheath. BSYSC significantly increased expressions of PDGFRα and CNPase in mice with EAE on 40 dpi. Furthermore, BSYSC treatment increased the expressions of LIF, LIFR and Nkx6.2 and reduced Sema3A and NRP-1 in EAE mice on 40 dpi.

CONCLUSIONS

The data demonstrated that BSYSC exhibited the neuroprotective effect against EAE by promoting oligodendrocyte progenitor cells (OPCs) proliferation and differentiation, thus facilitating remyelination. Sema3A/NRP-1, LIF/LIFR and Nkx6.2 are likely contributed to the effects of BSYSC on OPCs.

Jisuikang, a Chinese herbal formula, increases neurotrophic factor expression and promotes the recovery of neurological function after spinal cord injury

The Chinese medicine compound, Jisuikang, can promote recovery of neurological function by inhibiting lipid peroxidation, scavenging oxygen free radicals, and effectively improving the local microenvironment after spinal cord injury. However, the mechanism remains unclear. Thus, we established a rat model of acute spinal cord injury using a modified version of Allen's method. Jisuikang (50, 25, and 12.5 g/kg/d) and prednisolone were administered 30 minutes after anesthesia. Basso, Beattie, and Bresnahan locomotor scale scores and the oblique board test showed improved motor function recovery in the prednisone group and moderate-dose Jisuikang group compared with the other groups at 3-7 days post-injury. The rats in the moderate-dose Jisuikang group recovered best at 14 days post-injury. Hematoxylin-eosin staining and transmission electron microscopy showed that the survival rate of neurons in treatment groups increased after 3-7 days of administration. Further, the structure of neurons and glial cells was more distinct, especially in prednisolone and moderate-dose Jisuikang groups. Western blot assay and immunohistochemistry showed that expression of brain-derived neurotrophic factor (BDNF) in injured segments was maintained at a high level after 7-14 days of treatment. In contrast, expression of nerve growth factor (NGF) was down-regulated at 7 days after spinal cord injury. Real-time fluorescence quantitative polymerase chain reaction showed that expression of BDNF and NGF mRNA was induced in injured segments by prednisolone and Jisuikang. At 3-7 days after injury, the effect of prednisolone was greater, while 14 days after injury, the effect of moderate-dose Jisuikang was greater. These results confirm that Jisuikang can upregulate BDNF and NGF expression for a prolonged period after spinal cord injury and promote repair of acute spinal cord injury, with its effect being similar to prednisolone.