minocycline and myelin-oligodendrocyte-glycoprotein-(35-55)

Minocycline, which has long been used as a broad-spectrum antibiotic, also exhibits non-antibiotic properties such as inhibition of inflammation and angiogenesis. In this study, we show that minocycline significantly enhances the generation of dendritic cells (DCs) from mouse bone marrow (BM) cells when used together with GM-CSF and IL-4. DCs generated from BM cells in the presence of minocycline (Mino-DCs) demonstrate the characteristics of regulatory DCs. Compared with control DCs, Mino-DCs are resistant to subsequent maturation stimuli, impaired in MHC class II-restricted exogenous Ag presentation, and show decreased cytokine secretion. Mino-DCs also show decreased ability to prime allogeneic-specific T cells, while increasing the expansion of CD4+CD25+Foxp3+ T regulatory cells both in vitro and in vivo. In addition, pretreatment with MOG35-55 peptide-pulsed Mino-DCs ameliorates clinical signs of experimental autoimmune encephalitis induced by MOG peptide injection. Our study identifies minocycline as a new pharmacological agent that could be potentially used to increase the production of regulatory DCs for cell therapy to treat autoimmune disorders, allergy, and transplant rejection.

Topics: Adoptive Transfer; Animals; Antigen Presentation; Bone Marrow Cells; Cell Proliferation; Cells, Cultured; Dendritic Cells; Encephalomyelitis, Autoimmune, Experimental; Female; Lymphocyte Culture Test, Mixed; Mice, Inbred BALB C; Mice, Inbred C57BL; Minocycline; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; T-Lymphocytes; T-Lymphocytes, Regulatory

Combination therapies with existing or novel drugs for multiple sclerosis (MS) have great clinical potential to improve MS treatment outcomes. Our previous studies had confirmed that the combined treatment of minocycline and prednisone produced beneficial effects partially through preventing the reduction of brain-derived neurotrophic factor and nerve growth factor mRNA expression in the cerebral cortex of experimental autoimmune encephalomyelitis (EAE) mice. As high-dose methylprednisolone administered intravenously has more superior efficacy than oral prednisone and had been provided as a stable therapy for MS patients at the onset of an acute relapse, we further evaluated the effects of combined methylprednisolone and minocycline at suboptimal doses on EAE mice at the acute stage in this study. Interferon gamma (IFN-γ) and interleukin-4 (IL-4), the hallmark cytokines that direct Th1 and Th2 development and play an important role in the pathogenesis of MS as well as EAE, were also assayed. Obtained results showed that combined treatment could successfully attenuate severe clinical deficit and suppress histopathological events in EAE. In addition, reduced IFN-γ and increased IL-4 production/expression were found in the splenocytes culture supernatants and brains of EAE mice by the combined treatment. Our data indicate that the combination of methylprednisolone and minocycline may be a promising therapy for MS.

Topics: Analysis of Variance; Animals; Anti-Bacterial Agents; Brain-Derived Neurotrophic Factor; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Synergism; Encephalomyelitis, Autoimmune, Experimental; Enzyme-Linked Immunosorbent Assay; Female; Freund's Adjuvant; Glycoproteins; Interferon-gamma; Interleukin-4; Methylprednisolone; Mice; Mice, Inbred C57BL; Minocycline; Myelin-Oligodendrocyte Glycoprotein; Nerve Growth Factor; Neuroprotective Agents; Peptide Fragments; RNA, Messenger

The complex manifestations of chronic multiple sclerosis (MS)are due in part to widespread axonal abnormalities that affect lesional and nonlesional areas in the central nervous system. We describe an association between microglial activation and axon/oligodendrocyte pathology at nodal and paranodal domains in normal-appearing white matter (NAWM) of MS cases and in experimental autoimmune encephalomyelitis (EAE). The extent of paranodal axoglial (neurofascin-155(+)/Caspr1(+)) disruption correlated with local microglial inflammation and axonal injury (expression of nonphosphorylated neurofilaments) in MS NAWM. These changes were independent of demyelinating lesions and did not correlate with the density of infiltrating lymphocytes. Similar axoglial alterations were seen in the subcortical white matter of Parkinson disease cases and in preclinical EAE, at a time point when there is microglial activation before the infiltration of immune cells. Disruption of the axoglial unit in adjuvant-immunized animals was reversible and coincided with the resolution of microglial inflammation; paranodal damage and microglial inflammation persisted in chronic EAE. Axoglial integrity could be preserved by the administration of minocycline, which inhibited microglial activation, in actively immunized animals. These data indicate that, in MS NAWM, permanent disruption to axoglial domains in an environment of microglial inflammation is an early indicator of axonal injury that likely affects nerve conduction and may contribute to physiologic dysfunction.

Topics: Adult; Aged; Analysis of Variance; Animals; Anti-Bacterial Agents; Axons; Brain; Calcium-Binding Proteins; Caspase 1; CD3 Complex; DNA-Binding Proteins; Encephalomyelitis, Autoimmune, Experimental; Female; Gene Expression Regulation; Glycoproteins; HLA-DR Antigens; Humans; Indoles; Kv1.2 Potassium Channel; Male; Mice; Mice, Inbred C57BL; Microfilament Proteins; Microglia; Microscopy, Confocal; Middle Aged; Minocycline; Multiple Sclerosis; Myelin-Oligodendrocyte Glycoprotein; NAV1.6 Voltage-Gated Sodium Channel; Nerve Tissue Proteins; Neurofilament Proteins; Nitric Oxide Synthase Type II; Peptide Fragments; Postmortem Changes; Ranvier's Nodes; Sodium Channels; Toll-Like Receptor 4

Multiple sclerosis (MS) is the most common inflammatory demyelinating disorder of the central nervous system (CNS). An approach to improve MS treatment is to identify a rational combination of new medications or existing therapies that impact different aspects of the disease process. Statins are effective in the treatment of MS animal models and are promising candidates for future treatment. Minocycline ameliorates clinical severity of experimental autoimmune encephalomyelitis (EAE) and exhibits several anti-inflammatory and neuroprotective activities. In this study, we tested whether the combination of these two drugs could produce beneficial effects in EAE mice immunized with myelin oligodendrocyte protein (MOG). Our findings show that combined treatment, compared to using the medications alone, resulted in a significant reduction in disease severity, in both the acute and chronic phases of the disease, along with attenuation of inflammation, demyelination and axonal loss. Stereological analysis revealed that the combined treatment significantly guarded against neuroinflammation and neurodegeneration. Moreover, a significant suppression of anti-MOG antibody production in animals treated with the two medications was found. In conclusion, our findings prove that this combination of drugs is neuroprotective and suppresses the severity of EAE. Furthermore, this pharmacological approach appears to be promising as a future therapeutic strategy to control MS.

Topics: Animals; Anti-Bacterial Agents; Atorvastatin; Body Weight; Cell Proliferation; Cytokines; Drug Therapy, Combination; Encephalomyelitis, Autoimmune, Experimental; Enzyme-Linked Immunosorbent Assay; Female; Glial Fibrillary Acidic Protein; Glycoproteins; Heptanoic Acids; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Mice; Mice, Inbred C57BL; Minocycline; Multiple Sclerosis; Myelin-Oligodendrocyte Glycoprotein; Neurologic Examination; Peptide Fragments; Pyrroles; Stereotaxic Techniques; T-Lymphocytes; Time Factors