Suppression of experimental autoimmune encephalomyelitis by interleukin-10 transduced neural stem/progenitor cells

A Review of the Evidence for Tryptophan and the Kynurenine Pathway as a Regulator of Stem Cell Niches in Health and Disease

Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body's ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells. The KP is the major enzymatic pathway for sequentially catabolising the essential amino acid tryptophan (TRP), resulting in key metabolites including kynurenine, kynurenic acid, and quinolinic acid (QUIN). QUIN metabolism transitions into the adjoining de novo pathway for nicotinamide adenine dinucleotide (NAD) production, a critical cofactor in many fundamental cellular biochemical pathways. How stem cells uptake and utilise TRP varies between different species and stem cell types, because of their expression of transporters and responses to inflammatory cytokines. Several KP metabolites are physiologically active, with either beneficial or detrimental outcomes, and evidence of this is presented relating to several stem cell types, which is important as they may exert a significant impact on surrounding differentiated cells, particularly if they metabolise or secrete metabolites differently. Interferon-gamma (IFN-γ) in mesenchymal stromal cells, for instance, highly upregulates rate-limiting enzyme indoleamine-2,3-dioxygenase (IDO-1), initiating TRP depletion and production of metabolites including kynurenine/kynurenic acid, known agonists of the Aryl hydrocarbon receptor (AhR) transcription factor. AhR transcriptionally regulates an immunosuppressive phenotype, making them attractive for regenerative therapy. We also draw attention to important gaps in knowledge for future studies, which will underpin future application for stem cell-based cellular therapies or optimising drugs which can modulate the KP in innate stem cell populations, for disease treatment.

Neuroprotective effects of interleukin 10 in spinal cord injury

Spinal cord injury (SCI) starts with a mechanical and/or bio-chemical insult, followed by a secondary phase, leading progressively to severe collapse of the nerve tissue. Compared to the peripheral nervous system, injured spinal cord is characterized by weak axonal regeneration, which leaves most patients impaired or paralyzed throughout lifetime. Therefore, confining, alleviating, or reducing the expansion of secondary injuries and promoting functional connections between rostral and caudal regions of lesion are the main goals of SCI therapy. Interleukin 10 (IL-10), as a pivotal anti-inflammatory and immunomodulatory cytokine, exerts a wide spectrum of positive effects in the treatment of SCI. The mechanisms underlying therapeutic effects mainly include anti-oxidative stress, limiting excessive inflammation, anti-apoptosis, antinociceptive effects, etc. Furthermore, IL-10 displays synergistic effects when combined with cell transplantation or neurotrophic factor, enhancing treatment outcomes. This review lists pleiotropic mechanisms underlying IL-10-mediated neuroprotection after SCI, which may offer fresh perspectives for clinical translation.

Genetically Engineered Artificial Microvesicles Carrying Nerve Growth Factor Restrains the Progression of Autoimmune Encephalomyelitis in an Experimental Mouse Model

Multiple sclerosis (MS) is an incurable, progressive chronic autoimmune demyelinating disease. Therapy for MS is based on slowing down the processes of neurodegeneration and suppressing the immune system of patients. MS is accompanied by inflammation, axon-degeneration and neurogliosis in the central nervous system. One of the directions for a new effective treatment for MS is cellular, subcellular, as well as gene therapy. We investigated the therapeutic potential of adipose mesenchymal stem cell (ADMSC) derived, cytochalasin B induced artificial microvesicles (MVs) expressing nerve growth factor (NGF) on a mouse model of multiple sclerosis experimental autoimmune encephalomyelitis (EAE). These ADMSC-MVs-NGF were tested using histological, immunocytochemical and molecular genetic methods after being injected into the tail vein of animals on the 14th and 21st days post EAE induction. ADMSC-MVs-NGF contained the target protein inside the cytoplasm. Their injection into the caudal vein led to a significant decrease in neurogliosis at the 14th and 21st days post EAE induction. Artificial ADMSC-MVs-NGF stimulate axon regeneration and can modulate gliosis in the EAE model.

Autoimmune Neuroinflammatory Diseases: Role of Interleukins

Autoimmune neuroinflammatory diseases are a group of disorders resulting from abnormal immune responses in the nervous system, causing inflammation and tissue damage. The interleukin (IL) family of cytokines, especially IL-1, IL-6, and IL-17, plays a critical role in the pathogenesis of these diseases. IL-1 is involved in the activation of immune cells, production of pro-inflammatory cytokines, and promotion of blood-brain barrier breakdown. IL-6 is essential for the differentiation of T cells into Th17 cells and has been implicated in the initiation and progression of neuroinflammation. IL-17 is a potent pro-inflammatory cytokine produced by Th17 cells that plays a crucial role in recruiting immune cells to sites of inflammation. This review summarizes the current understanding of the roles of different interleukins in autoimmune neuroinflammatory diseases, including multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer's disease, neuromyelitis optica, and autoimmune encephalitis, and discusses the potential of targeting ILs as a therapeutic strategy against these diseases. We also highlight the need for further research to better understand the roles of ILs in autoimmune neuroinflammatory diseases and to identify new targets for treating these debilitating diseases.

Bacillus Calmette-Guérin Tokyo-172 vaccine provides age-related neuroprotection in actively induced and spontaneous experimental autoimmune encephalomyelitis models

Multiple sclerosis is the most common immune-mediated disorder affecting the central nervous system in young adults but still has no cure. Bacillus Calmette-Guérin (BCG) vaccine is reported to have non-specific anti-inflammatory effects and therapeutic benefits in autoimmune disorders including multiple sclerosis. However, the precise mechanism of action of BCG and the host immune response to it remain unclear. In this study, we aimed to investigate the efficacy of the BCG Tokyo-172 vaccine in suppressing experimental autoimmune encephalomyelitis (EAE). Groups of young and mature adult female C57BL/6J mice were BCG-vaccinated 1 month prior or 6 days after active EAE induction using myelin oligodendrocyte glycoprotein (MOG)35-55 peptide. Another group of 2D2 TCRMOG transgenic female mice was BCG-vaccinated before and after the onset of spontaneous EAE. BCG had an age-associated protective effect against active EAE only in wild-type mice vaccinated 1 month before EAE induction. Furthermore, the incidence of spontaneous EAE was significantly lower in BCG vaccinated 2D2 mice than in non-vaccinated controls. Protection against EAE was associated with reduced splenic T-cell proliferation in response to MOG35-55 peptide together with high frequency of CD8+ interleukin-10-secreting T cells in the spleen. In addition, microglia and astrocytes isolated from BCG-vaccinated mice showed polarization to anti-inflammatory M2 and A2 phenotypes, respectively. Our data provide new insights into the cell-mediated and humoral immune mechanisms underlying BCG vaccine-induced neuroprotection, potentially useful for developing better strategies for the treatment of MS.

Nobiletin attenuates inflammation via modulating proinflammatory and antiinflammatory cytokine expressions in an autoimmune encephalomyelitis mouse model

The aim of this study is to investigate the potential preventive and therapeutic effects of nobiletin by evaluating the expression of cytokines associated with inflammatory reactions in an autoimmune encephalomyelitis mouse model. A total of 60 male C57BL/6 mice aged between 8 and 10 weeks were used. Mice were divided into six groups (n = 10 mice per group): control, EAE, low-prophylaxis, high-prophylaxis, low-treatment and high-treatment. Experimental autoimmune encephalomyelitis (EAE) was induced by myelin oligodendrocyte glycoprotein (MOG) and pertussis toxin. Nobiletin was administered in low (25 mg/kg) and high (50 mg/kg) doses, intraperitoneally. The prophylactic and therapeutic effects of nobiletin on brain tissue and spinal cord were evaluated by expression of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), interferon gamma (IFNγ), IL-6, IL-10 and transforming growth factor-beta (TGF-β) using immunohistochemistry and real-time polymerase chain reaction (RT-PCR). Prophylactic and therapeutic use of nobiletin inhibited EAE-induced increase of TNF-α, IL-1β and IL-6 activities to alleviate inflammatory response in brain and spinal cord. Moreover, nobiletin supplement dramatically increased the IL-10, TGF-β and IFNγ expressions in prophylaxis and treatment groups compared with the EAE group in the brain and spinal cord. The results obtained from this study show that prophylactic and therapeutic nobiletin modulates expressions of proinflammatory and antiinflammatory cytokines in brain and spinal cord dose-dependent manner in EAE model. These data demonstrates that nobiletin has a potential to attenuate inflammation in EAE mouse model. These experimental findings need to be supported by clinical studies.

Gas6 Induces Myelination through Anti-Inflammatory IL-10 and TGF-β Upregulation in White Matter and Glia

The Gas6–TAM (Tyro3, Axl, Mer) ligand–receptor system is believed to promote central nervous system (CNS) (re)myelination and glial cell development. An additional important function of Gas6–TAM signalling appears to be the regulation of immunity and inflammation, which remains to be fully elucidated in the CNS. Here, we characterised the expression of TAM receptors and ligands in individual CNS glial cell types, observing high expression of Gas6 and the TAM receptors, Mer and Axl, in microglia, and high expression of Tyro3 in astrocytes. We also investigated the effect of Gas6 on the inflammatory cytokine response in the optic nerve and in mixed glial cell cultures from wildtype and single TAM receptor knockout mice. In wildtype and Mer-deficient cultures, Gas6 significantly stimulated the expression of the anti-inflammatory/pro-repair cytokines interleukin 10 (IL-10) and transforming growth factor β (TGF-β), whereas this effect was absent in either Tyro3 or Axl knockout cultures. Furthermore, Gas6 caused upregulation of myelin basic protein (MBP) expression in optic nerves, which was blocked by a neutralising antibody against IL-10. In conclusion, our data show that microglia are both a major source of Gas6 as well as an effector of Gas6 action in the CNS through the upregulation of anti-inflammatory and pro-repair mediators. Furthermore, the presence of both Axl and Tyro3 receptors appears to be necessary for these effects of Gas6. In addition, IL-10, alongside suppressing inflammation and immunity, mediates the pro-myelinating mechanism of Gas6 action in the optic nerve. Therefore, Gas6 may present an attractive target for novel therapeutic interventions for demyelinating as well as neuroinflammatory disorders of the CNS.

The Regulatory Role of IL-10 in Neurodegenerative Diseases

IL-10, an immunosuppressive cytokine, is considered an important anti-inflammatory modulator of glial activation, preventing inflammation-mediated neuronal degeneration under pathological conditions. In this narrative review, we summarize recent insights about the role of IL-10 in the neurodegeneration associated with neuroinflammation, in diseases such as Multiple Sclerosis, Traumatic Brain Injury, Amyotrophic lateral sclerosis, Alzheimer’s Disease, and Parkinson’s Disease, focusing on the contribution of this cytokine not only in terms of protective action, but also as possibly responsible for clinical worsening. The knowledge of this double face of the same coin, regarding the biological role of the IL-10, could aid the development of targeted therapies useful for limiting neurodegenerative processes.

Artemisinin protects motoneurons against axotomy-induced apoptosis through activation of the PKA-Akt signaling pathway and promotes neural stem/progenitor cells differentiation into NeuN+ neurons

Brachial plexus axotomy is a common peripheral nerve trauma. Artemisinin, an FDA-approved antimalarial drug, has been described to possess neuroprotective properties. However, the specific mechanisms by which artemisinin protects neurons from axotomy-induced neurotoxicity remain to be elucidated. In this study, we assessed the neuroprotective effects of artemisinin on an experimental animal model of brachial plexus injury and explored the possible mechanisms involved. Artemisinin treatment restored both athletic ability and sensation of the affected upper limb, rescued motoneurons and attenuated the inflammatory response in the ventral horn of the spinal cord. Additionally, artemisinin inhibited the molecular signals of apoptosis, activated signaling pathways related to cell survival and induced NSCPs differentiation into NeuN-positive neurons. Further validation of the involved key signaling molecules, using an in vitro model of hydrogen peroxide-induced neurotoxicity, revealed that both the inhibition of PKA signaling pathway or the silencing of Akt reversed the neuroprotective action of artemisinin on motoneurons. Our results indicate that artemisinin provides neuroprotection against axotomy and hydrogen peroxide-induced neurotoxicity, an effect that might be mediated by the PKA-Akt signaling pathway.

Decreased number and impaired function of type 1 regulatory T cells in autoimmune diseases

Type 1 regulatory T (Tr1) cell is a special type of T regulatory cells with surface molecular markers such as lymphocyte-activation gene 3 and CD49b. A key property of Tr1 cells is the capability to produce high-level interleukin 10 (IL-10) upon activation, in a FOXP3-independent manner. The immunosuppressive function of IL-10 producing Tr1 cells has been extensively studied for many years. Autoimmune diseases (AIDs) are conditions in which the immune system breaks down and starts to attack the body. AIDs include inflammatory bowel disease, rheumatoid arthritis, multiple sclerosis (MS), type 1 diabetes mellitus, Greaves' disease, and so forth. In recent years, more and more studies have documented that the number of Tr1 cells is decreased and the function is inhibited in a variety of AIDs, among which MS is the most widely studied. The protocol for engineering Tr1 cell therapy has been established and is gradually being used in clinical practice in recent years. Tr1 cell therapy has been proven to be safe and effective, but it is mainly involved in myeloid leukemia, graft versus host disease currently. Its therapeutic role in AIDs still needs to be further explored. In this study, we will summarize the research advances of Tr1 cells in AIDs, which will provide useful information for treating AIDs through Tr1 cell therapy in the future.

The Interleukin-10 Family of Cytokines and Their Role in the CNS

Resident cells of the central nervous system (CNS) play an important role in detecting insults and initiating protective or sometimes detrimental host immunity. At peripheral sites, immune responses follow a biphasic course with the rapid, but transient, production of inflammatory mediators giving way to the delayed release of factors that promote resolution and repair. Within the CNS, it is well known that glial cells contribute to the onset and progression of neuroinflammation, but it is only now becoming apparent that microglia and astrocytes also play an important role in producing and responding to immunosuppressive factors that serve to limit the detrimental effects of such responses. Interleukin-10 (IL-10) is generally considered to be the quintessential immunosuppressive cytokine, and its ability to resolve inflammation and promote wound repair at peripheral sites is well documented. In the present review article, we discuss the evidence for the production of IL-10 by glia, and describe the ability of CNS cells, including microglia and astrocytes, to respond to this suppressive factor. Furthermore, we review the literature for the expression of other members of the IL-10 cytokine family, IL-19, IL-20, IL-22 and IL-24, within the brain, and discuss the evidence of a role for these poorly understood cytokines in the regulation of infectious and sterile neuroinflammation. In concert, the available data indicate that glia can produce IL-10 and the related cytokines IL-19 and IL-24 in a delayed manner, and these cytokines can limit glial inflammatory responses and/or provide protection against CNS insult. However, the roles of other IL-10 family members within the CNS remain unclear, with IL-20 appearing to act as a pro-inflammatory factor, while IL-22 may play a protective role in some instances and a detrimental role in others, perhaps reflecting the pleiotropic nature of this cytokine family. What is clear is that our current understanding of the role of IL-10 and related cytokines within the CNS is limited at best, and further research is required to define the actions of this understudied family in inflammatory brain disorders.

Pioglitazone is superior to quetiapine, clozapine and tamoxifen at alleviating experimental autoimmune encephalomyelitis in mice

Recent evidence suggests that clozapine and quetiapine (atypical antipsychotics), tamoxifen (selective-estrogen receptor modulator) and pioglitazone (PPARγ agonist) may improve functional recovery in multiple sclerosis (MS). We have compared the effectiveness of oral administration of these drugs, beginning at peak disease, at reducing ascending paralysis, motor deficits and demyelination in mice subjected to experimental autoimmune encephalomyelitis (EAE). Mice were immunized with an immunogenic peptide corresponding to amino acids 35-55 of the myelin oligodendrocyte glycoprotein (MOG_35-55) in complete Freund's adjuvant and injected with pertussis toxin to induce EAE. Unlike clozapine, quetiapine and tamoxifen, administration of pioglitazone beginning at peak disease decreased both clinical scores and lumbar white matter loss in EAE mice. Using kinematic gait analysis, we found that pioglitazone also maintained normal movement of the hip, knee and ankle joints for at least 44 days after MOG_35-55 immunization. This long-lasting preservation of hindleg joint movements was accompanied by reduced white matter loss, microglial and macrophage activation and the expression of pro-inflammatory genes in the lumbar spinal cords of EAE mice. These results support clinical findings that suggest pioglitazone may reduce the progressive loss of motor function in MS by decreasing inflammation and myelin damage.

Stem Cell Therapy for Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory, autoimmune, and neurodegenerative disease of the central nervous system (CNS). It is characterized by demyelination and neuronal loss that is induced by attack of autoreactive T cells to the myelin sheath and endogenous remyelination failure, eventually leading to functional neurological disability. Although recent evidence suggests that MS relapses are induced by environmental and exogenous triggers such as viral infections in a genetic background, its very complex pathogenesis is not completely understood. Therefore, the efficiency of current immunosuppression-based therapies of MS is too low, and emerging disease-modifying immunomodulatory agents such as fingolimod and dimethyl fumarate cannot stop progressive neurodegenerative process. Thus, the cell replacement therapy approach that aims to overcome neuronal cell loss and remyelination failure and to increase endogenous myelin repair capacity is considered as an alternative treatment option. A wide variety of preclinical studies, using experimental autoimmune encephalomyelitis model of MS, have recently shown that grafted cells with different origins including mesenchymal stem cells (MSCs), neural precursor and stem cells, and induced-pluripotent stem cells have the ability to repair CNS lesions and to recover functional neurological deficits. The results of ongoing autologous hematopoietic stem cell therapy studies, with the advantage of peripheral administration to the patients, have suggested that cell replacement therapy is also a feasible option for immunomodulatory treatment of MS. In this chapter, we overview cell sources and applications of the stem cell therapy for treatment of MS. We also discuss challenges including those associated with administration route, immune responses to grafted cells, integration of these cells to existing neural circuits, and risk of tumor growth. Finally, future prospects of stem cell therapy for MS are addressed.

M2 microglia promotes neurogenesis and oligodendrogenesis from neural stem/progenitor cells via the PPARγ signaling pathway

Neural stem/progenitor cells (NSPCs) are an important source of cells for cell replacement therapy after nerve injury. How to induce NSPCs differentiation towards neurons and oligodendrocytes is a challenging issue in neuroscience research. In the present study, we polarized microglia into M1 and M2 phenotype, used their supernatants to induce NSPCs differentiation, and investigated the effects of different microglia phenotypes on NSPCs differentiation and their mechanisms. We discovered that, after exposure to M1 phenotype supernatant, NSPCs differentiated into fewer Tuj-1+ and Olig2+ cells, but more GFAP+ cells. Meanwhile, a significantly increased number of Tuj-1+ and Olig2+ cells and smaller number of GFAP+ cells were generated by M2 microglia supernatant-induced NSPCs differentiation. We also observed that 15d-PGJ₂, an endogenous ligand of PPARγ, was elevated in M2 phenotype supernatant and could activate PPARγ expression in NSPCs, whereas use of the PPARγ inhibitor GW9662, could reduce the percentage of differentiated neurons and oligodendrocytes. Our study results confirm that M2 microglia supernatant can activate the PPARγ signaling pathway and promote neurogenesis and oligodendrogenesis from NSPCs differentiation. The present study provides a further theoretical basis for induction of NSPCs oriented differentiation.

Human periodontal ligament stem cells secretome from multiple sclerosis patients suppresses NALP3 inflammasome activation in experimental autoimmune encephalomyelitis

Research in recent years has largely explored the immunomodulatory effects of mesenchymal stem cells (MSCs) and their secretory products, called “secretome,” in the treatment of neuroinflammatory diseases. Here, we examined whether such immunosuppressive effects might be elicited due to inflammasome inactivation. To this end, we treated experimental autoimmune encephalomyelitis (EAE) mice model of multiple sclerosis (MS) with the conditioned medium or purified exosomes/microvesicles (EMVs) obtained from relapsing-remitting-MS patients human periodontal ligament stem cells (hPDLSCs) and investigated the regulation of NALP3 inflammasome. We noticed enhanced expression of NALP3, Cleaved Caspase 1, interleukin (IL)-1β, and IL-18 in EAE mouse spinal cord. Conversely, hPDLSCs-conditioned medium and EMVs significantly blocked NALP3 inflammasome activation and provided protection from EAE. Reduction in NALP3, Cleaved Caspase 1, IL-1β, and IL-18 level was noticed in conditioned medium and EMVs-treated EAE mice. Pro-inflammatory Toll-like receptor (TLR)-4 and nuclear factor (NF)-κB were elevated in EAE, while hPDLSCs-conditioned medium and EMVs treatment reduced their expression and increased IκB-α expression. Characterization of hPDLSCs-conditioned medium showed substantial level of anti-inflammatory IL-10, transforming growth factor (TGF)-β, and stromal cell–derived factor 1α (SDF-1α). We propose that the immunosuppressive role of hPDLSCs-derived conditioned medium and EMVs in EAE mice may partly attribute to the presence of soluble immunomodulatory factors, NALP3 inflammasome inactivation, and NF-κB reduction.

Neural Stem Cell-Based Regenerative Approaches for the Treatment of Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, autoimmune, inflammatory, and demyelinating disorder of the central nervous system (CNS), which ultimately leads to axonal loss and permanent neurological disability. Current treatments for MS are largely comprised of medications that are either immunomodulatory or immunosuppressive and are aimed at reducing the frequency and intensity of relapses. Neural stem cells (NSCs) in the adult brain can differentiate into oligodendrocytes in a context-specific manner and are shown to be involved in the remyelination in these patients. NSCs may exert their beneficial effects not only through oligodendrocyte replacement but also by providing trophic support and immunomodulation, a phenomenon now known as "therapeutic plasticity." In this review, we first provided an update on the current knowledge regarding MS pathogenesis and the role of immune cells, microglia, and oligodendrocytes in MS disease progression. Next, we reviewed the current progress on research aimed toward stimulating endogenous NSC proliferation and differentiation to oligodendrocytes in vivo and in animal models of demyelination. In addition, we explored the neuroprotective and immunomodulatory effects of transplanted exogenous NSCs on T cell activation, microglial activation, and endogenous remyelination and their effects on the pathological process and prognosis in animal models of MS. Finally, we examined various protocols to generate genetically engineered NSCs as a potential therapy for MS. Overall, this review highlights the studies involving the immunomodulatory, neurotrophic, and regenerative effects of NSCs and novel methods aiming at stimulating the potential of NSCs for the treatment of MS.

The secretome of periodontal ligament stem cells from MS patients protects against EAE

Manipulation of stem cells or stem cells-derived secretome has emerged as a novel alternative therapeutic option for multiple sclerosis (MS). Here we show that human periodontal ligament stem cells (hPDLSCs)-derived conditioned medium (hPDLSCs-CM) and purified exosomes/microvesicles (hPDLSCs-EMVs) obtained from Relapsing Remitting (RR)-MS patients and healthy donors block experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing anti-inflammatory and immunosuppressive effects in spinal cord and spleen, and reverse disease progression by restoring tissue integrity via remyelination in the spinal cord. We show that hPDLSCs-CM and hPDLSCs-EMVs reduce pro-inflammatory cytokines IL-17, IFN-γ, IL-1β, IL-6, TNF-α, and induce anti-inflammatory IL-10. In addition, apoptosis related STAT1, p53, Caspase 3, and Bax expressions were attenuated. Our findings unravel the immunosuppressive effects of hPDLSCs-CM and hPDLSCs-EMVs in EAE mice, and suggest simple alternative autologous source for patient-customized cell-free targeting treatment in MS patients.

ILs-3, 6 and 11 increase, but ILs-10 and 24 decrease stemness of human prostate cancer cells in vitro

Cancer stem cells (CSCs) are associated with cancer recurrence and metastasis. Prostate cancer cells often metastasize to the bone with a complex microenvironment of cytokines favoring cell survival. In this study, the cell stemness influence of a group of interleukins including IL-3, 6, 10, 11 and 24 on human prostate cancer cell lines LNCaP and PC-3 was explored in vitro. Sulforhodamine B(SRB) and 5-ethynyl-2′-deoxyuridine (EdU) assays were applied to examine the effect on cell proliferation, and wound healing and transwell assays were used for migration and invasion studies, in addition to colony formation, Western blotting and flowcytometry for the expression of stemness factors and chemotherapy sensitivity. We observed that ILs-3, 6 and 11 stimulated while ILs-10 and 24 inhibited the growth, invasion and migration of both cell lines. Interestingly, ILs-3, 6 and 11 significantly promoted colony formation and increased the expression of SOX2, CD44 and ABCG2 in both prostate cancer cell lines. However, ILs-10 and 24 showed the opposite effect on the expression of these factors. In line with the above findings, treatment with either IL-3 or IL-6 or IL-11 decreased the chemosensitivity to docetaxel while treatment with either IL-10 or IL-24 increased the sensitivity of docetaxel chemotherapy. In conclusion, our results suggest that ILs-3, 6 and 11 function as tumor promoters while ILs-10 and 24 function as tumor suppressors in the prostate cancer cell lines PC-3 and LNCaP in vitro, and such differences may attribute to their different effect on the stemness of PCa cells.

Protective effect of cytosolic phospholipase A2 inhibition against inflammation and degeneration by promoting regulatory T cells in rats with experimental autoimmune encephalomyelitis

Cytosolic phospholipase A2 (cPLA2) is the rate-limiting enzyme that initiates the production of various inflammatory mediators. Previous studies have shown that inhibiting cPLA2 exerts a neuroprotective effect on experimental autoimmune encephalomyelitis (EAE) by ameliorating the severity of the disease and influencing Th1 and Th17 responses. However, it remains unclear whether treatment with a cPLA2 inhibitor will influence the regulatory T cells (Tregs) that play a critical role in maintaining immune homeostasis and preventing autoimmune diseases. In this study, the cPLA2 inhibitor AX059 reduced the onset and progression of EAE in Lewis rats. In addition, this effect was accompanied by activation of Tregs and alterations in the expression of their various cytokines. The study therefore demonstrated that Tregs are involved in the immunomodulatory effect mediated by cPLA2 inhibition. These findings may have clinical application in the treatment of multiple sclerosis.