We observed the therapeutic effect of Fasudil and explored its mechanisms in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Fasudil, a selective Rho kinase (ROCK) inhibitor, was injected intraperitoneally at 40 mg/kg/d in early and late stages of EAE induction. Fasudil ameliorated the clinical severity of EAE at different stages, and decreased the expression of ROCK-II in spleen, accompanied by an improvement in demyelination and inhibition of inflammatory cells. Fasudil mainly inhibited CD4+IL-17+ T cells in early treatment, but also elevated CD4+IL-10+ regulatory T cells and IL-10 production in late treatment. The treatment of Fasudil shifted inflammatory M1 to anti-inflammatory M2 macrophages in both early and late treatment, being shown by inhibiting CD16/32, iNOS, IL-12, TLR4 and CD40 and increasing CD206, Arg-1, IL-10 and CD14 in spleen. By using Western blot and immunohistochemistry, iNOS and Arg-1, as two most specific markers for M1 and M2, was inhibited or induced in splenic macrophages and spinal cords of EAE mice treated with Fasudil. In vitro experiments also indicate that Fasudil shifts M1 to M2 phenotype, which does not require the participation or auxiliary of other cells. The polarization of M2 macrophages was associated with the decrease of inflammatory cytokine IL-1β, TNF-α and MCP-1. These results demonstrate that Fasudil has therapeutic potential in EAE possibly through inducing the polarization of M2 macrophages and inhibiting inflammatory responses.

Macrophages/microglia exhibit phenotypic and functional heterogeneity under physiological and pathological conditions. Owing to this heterogeneity, the polarization of macrophages/microglia is capable of effecting both detrimental and beneficial outcomes in various disease processes. In this study, murine microglial cell line BV-2 and primary microglia were used as cell models to elucidate the polarization of microglia. Using flow cytometry, Western blot, chemical/enzymatic determination, and immunohistochemistry, treatment with LPS primed microglia into the M1 phenotype in both BV-2 cells and primary microglia, while fasudil skewed LPS-stimulated M1 toward M2 microglia, which showed lower NF-κB activity and inflammatory cytokines IL-1ß, IL-6, and TNF-a, and increased anti-inflammatory cytokine IL-10. To examine whether the regulatory role of LPS and fasudil on microglia can occur in vivo, mice were administered LPS (25 µg/10 µl) via nasal instillation every other day for 1 month. The results demonstrated that LPS also triggered iNOS⁺/CD11b⁺ M1 microglia in the brain, while fasudil increased Arg-1⁺/CD11b⁺ M2 microglia, although the difference did not reach statistical significance. Fasudil-conditioned microglia medium promoted a neuroprotective effect against PC12 neurons, suggesting that fasudil-induced M2 microglia contribute to the survival of neurons. These results indicate a new treatment option whereby fasudil inhibits the inflammatory response by controlling a helpful polarization in microglia/macrophages.

Fasudil ameliorates disease progression in EAE, acting possibly through antiinflammatory pathway.

Activated microglia, especially polarized M1 cells, produce pro-inflammatory cytokines and free radicals, thereby contributing directly to neuroinflammation and various brain disorders. Given that excessive or chronic neuroinflammation within the central nervous system (CNS) exacerbates neuronal damage, molecules that modulate neuroinflammation are candidates as neuroprotective agents. In this study, we provide evidence that Safflor yellow (SY), the main active component in the traditional Chinese medicine safflower, modulates inflammatory responses by acting directly on BV2 microglia. LPS stimulated BV2 cells to upregulate expression of TLR4-Myd88 and MAPK-NF-κB signaling pathways and to release IL-1β, IL-6, TNF-α, and COX-2. However, SY treatment inhibited expression of TLR4-Myd88 and p-38/p-JNK-NF-κB, downregulated expression of iNOS, CD16/32, and IL-12, and upregulated CD206 and IL-10. In conclusion, our results demonstrate that SY exerts an anti-inflammatory effect on BV2 microglia, possibly through TLR-4/p-38/p-JNK/ NF-κB signaling pathways and the conversion of microglia from inflammatory M1 to an anti-inflammatory M2 phenotype.

Keywords: Experimental autoimmune encephalomyelitis r Fasudil r Macrophage polarization r Rho kinase inhibitor r T-cell regulation Additional supporting information may be found in the online version of this article at the publisher's web-site IntroductionMultiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), which is characterized by chronicCorrespondence: Prof. Bao-Guo Xiao e-mail: bgxiao@shmu.edu.cn inflammation, myelin destruction, axonal loss, and neurological disability [1]. The exact cause of MS is still unknown, but the pathogenesis of MS/experimental autoimmune encephalomyelitis (EAE) is known to involve the following: (i) myelin-specific T cells are initially activated, (ii) activated T cells migrate across the blood-brain barrier (BBB) and infiltrate the CNS parenchyma, (iii) infiltrated T cells produce proinflammatory cytokines, which [6]. Despite these detrimental roles of macrophages within the injured CNS, many studies have also reported beneficial roles of macrophages. Treatment with M2 macrophages resulted in an attenuation of EAE progression [7,8].Given that polarized macrophages are reversible in a well-defined microenvironment, the polarization of M1 cells and M2 cells has become a new therapeutic target for MS. Rho-kinase (ROCK), a serine/threonine kinase, plays the role of molecular switch by regulating cell migration, proliferation, and survival [7]. A series of studies have demonstrated that the expression and/or activity of ROCK were increased in different EAE models [9][10][11][12][13] due to the release of inhibitory molecules (such as Nogo A, MAG, and Omgp) from damaged CNS tissues that activated the Rho/ROCK signal transduction pathway [14]. Inhibition of ROCK resulted in accelerated regeneration and enhanced functional recovery, which has also proved to be efficacious in animal models of stroke [15], MS [9-13], ALS [16], Alzheimer's disease [17], and Parkinson's diseases [18,19]. ROCK is therefore considered a promising drug target for preventing neurodegeneration and stimulating neuroregeneration in several neurological diseases [20]. Previous investigations from our group and other labs have indicated that the ROCK inhibitor Fasudil ameliorates the clinical severity of EAE in different models and at different stages [9][10][11]13], accompanied by reduced demyelination and inhibition of neuroinflammation [9,10,12,13]. Mechanisms underlying the therapeutic potential of Fasudil in EAE models include (i) downregulation of Th17 and Th1 T cells [9,10], (ii) protection of BBB and blood-spinal cord barrier integrity [11], (iii) inhibition of TLR-4 and p-NF-κB/p65 inflammatory axis [12], and (iv) shift from M1 to M2 macrophages [13]. Although there are several publications describing the therapeutic effects and immunological changes of Fasudil in EAE models, little is known about its immunomodulatory effect on macrophages and T cells. In addition, given that Fasudil has certain limitations in clinical practice, including a relatively narrow safety window, it...

Fasudil exhibited multitarget therapeutic effect in APP/PS1 Tg mice. The study provides preclinical evidence that Fasudil treatment ameliorated memory deficits in APP/PS1 Tg mice, accompanied by the reduction of Aβ deposition and Tau protein phosphorylation, the decrease of BACE and the increase of PSD-95, as well as inhibition of TLRs-NF-κB-MyD88 inflammatory cytokine axis. However, these results still need to be repeated and confirmed before clinical application.

We report the development of sponge Haliclona sp. spicules, referred to as SHS, and its topical application in skin delivery of hydrophilic biomacromolecules, a series of fluorescein isothiocyanate-dextrans (FDs). SHS are silicious oxeas which are sharp-edged and rod-shaped (∼120 μm in length and ∼7 μm in diameter). SHS can physically disrupt skin in a dose-dependent manner and retain within the skin over at least 72 h, which allows sustained skin penetration of hydrophilic biomacromolecules. The magnitude of enhancement of FD delivery into skin induced by SHS treatment was dependent on its molecular weight. Specifically, SHS topical application enhanced FD-10 (MW: 10 kDa) penetration into porcine skin in vitro by 33.09 ± 7.16-fold compared to control group (p < 0.01). SHS dramatically increased the accumulation of FD-10 into and across the dermis by 62.32 ± 13.48-fold compared to the control group (p < 0.01). In vivo experiments performed using BALB/c mice also confirmed the effectiveness of SHS topical application; the skin absorption of FD-10 with SHS topical application was 72.14 ± 48.75-fold (p < 0.05) and 15.39 ± 9.91-fold (p < 0.05) higher than those from the PBS and Dermaroller microneedling, respectively. Further, skin irritation study and transepidermal water loss (TEWL) measurement using guinea pig skin in vivo indicated that skin disruption induced by SHS treatment is self-limited and can be recovered with time and efficiently. SHS can offer a safe, effective, and sustained skin delivery of hydrophilic biomacromolecules and presents a promising platform technology for a wide range of cosmetic and medical applications.

Parkinson's disease (PD) is a chronic neurodegenerative disease of the central nervous system (CNS), characterized by a loss of dopaminergic neurons, which is thought to be caused by both genetic and environmental factors. Recent findings suggest that neuroinflammation may be a pathogenic factor in the onset and progression of sporadic PD. Here we explore the potential therapeutic effect of lipoic acid (LA) on a lipolysaccharide (LPS)-induced inflammatory PD model. Our results for the first time showed that LA administration improved motor dysfunction, protected dopaminergic neurons loss, and decreased α-synuclein accumulation in the substantia nigra (SN) area of brain. Further, LA inhibited the activation of nuclear factor-κB (NF-κB) and expression of pro-inflammatory molecules in M1 microglia. Taken together, these results suggest that LA may exert a profound neuroprotective effect and is thus a promising anti-neuroinflammatory and anti-oxidative agent for halting the progression of PD. Interventions aimed at either blocking microglia-derived inflammatory mediators or modulating the polarization of microglia may be potentially useful therapies that are worth further investigation.