Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease, mediated by pathogenic T helper 17 (Th17) cells. However, the therapeutic effect is accompanied by the fluctuation of the proportion and function of Th17 cells, which prompted us to find the key regulator of Th17 differentiation in MS. Here, we demonstrated that the triggering receptor expressed on myeloid cells 2 (TREM-2), a modulator of pattern recognition receptors on innate immune cells, was highly expressed on pathogenic CD4-positive T lymphocyte (CD4⁺ T) cells in both patients with MS and experimental autoimmune encephalomyelitis (EAE) mouse models. Conditional knockout of Trem-2 in CD4⁺ T cells significantly alleviated the disease activity and reduced Th17 cell infiltration, activation, differentiation, and inflammatory cytokine production and secretion in EAE mice. Furthermore, with Trem-2 knockout in vivo experiments and in vitro inhibitor assays, the TREM-2/zeta-chain associated protein kinase 70 (ZAP70)/signal transducer and activator of transcription 3 (STAT3) signal axis was essential for Th17 activation and differentiation in EAE progression. In conclusion, TREM-2 is a key regulator of pathogenic Th17 in EAE mice, and this sheds new light on the potential of this therapeutic target for MS.
Animals ; Humans ; Mice ; CD4-Positive T-Lymphocytes/pathology* ; Cell Differentiation ; Encephalomyelitis, Autoimmune, Experimental/metabolism* ; Mice, Inbred C57BL ; Multiple Sclerosis ; Th1 Cells/pathology*

OBJECTIVE: To examine the anti-inflammatory effect of grape seed extract (GSE) in animal and cellular models and explore its mechanism of action. METHODS: This study determined the inhibitory effect of GSE on macrophage inflammation and Th1 and Th17 polarization in vitro. Based on the in vitro results, the effects and mechanisms of GSE on multiple sclerosis (MS)-experimental autoimmune encephalomyelitis (EAE) mice model were further explored. The C57BL/6 mice were intragastrically administered with 50 mg/kg of GSE once a day from the 3rd day to the 27th day after immunization. The activation of microglia, the polarization of Th1 and Th17 and the inflammatory factors such as tumor necrosis factor- α (TNF- α), interleukin-1 β (IL-1 β), IL-6, IL-12, IL-17 and interferon-γ (IFN-γ) secreted by them were detected in vitro and in vivo by flow cytometry, enzyme linked immunosorbent assay (ELISA), immunofluorescence staining and Western blot, respectively. RESULTS: GSE reduced the secretion of TNF-α, IL-1 β and IL-6 in bone marrow-derived macrophages stimulated by lipopolysaccharide (P<0.01), inhibited the secretion of TNF-α, IL-1 β, IL-6, IL-12, IL-17 and IFN-γ in spleen cells of EAE mice immunized for 9 days (P<0.05 or P<0.01), and reduced the differentiation of Th1 and Th17 mediated by CD3 and CD28 factors (P<0.01). GSE significantly improved the clinical symptoms of EAE mice, and inhibited spinal cord demyelination and inflammatory cell infiltration. Peripherally, GSE downregulated the expression of toll-like-receptor 4 (TLR4) and Rho-associated kinase (ROCKII, P<0.05 or P<0.01), and inhibited the secretion of inflammatory factors (P<0.01 or P<0.05). In the central nervous system, GSE inhibited the infiltration of CD45⁺CD11b⁺ and CD45⁺CD4⁺ cells, and weakened the differentiation of Th1 and Th17 (P<0.05). Moreover, it reduced the secretion of inflammatory factors (P<0.01), and prevented the activation of microglia (P<0.05). CONCLUSION GSE had a beneficial effect on the pathogenesis and progression of EAE by inhibiting inflammatory response as a potential drug and strategy for the treatment of MS.
Mice ; Animals ; Encephalomyelitis, Autoimmune, Experimental/pathology* ; Grape Seed Extract/therapeutic use* ; Interleukin-17 ; Interleukin-1beta ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Th1 Cells ; Mice, Inbred C57BL ; Interferon-gamma/therapeutic use* ; Th17 Cells/metabolism* ; Interleukin-12/therapeutic use* ; Cytokines/metabolism*

OBJECTIVETo study the effects of Bushen Yisui Capsule (, BSYSC) on the oligodendrocyte lineage genes (Olig) 1 and Olig2 in C57BL/6 mice with experimental autoimmune encephalomyelitis (EAE) in order to explore the remyelination effect of BSYSC.

METHODSThe mice were randomly divided into normal control (NC), EAE model (EAE-M), prednisone acetate (PA, 6 mg/kg), BSYSC high-dose (3.02 g/kg) and BSYSC low-dose (1.51 g/kg) groups. The mice were induced by immunization with myelin oligodendrocyte glycoprotein (MOG) 35-55. The neurological function scores were assessed once daily. The pathological changes in mice brains were observed with hematoxylin-eosin (HE) staining and transmission electron microscope (TEM). The protein expressions of myelin basic protein (MBP), Olig1 and Olig2 in brains were measured by immunohistochemistry. The mRNA expressions of Olig1 and Olig 2 was also determined by quantitative real-time polymerase chain reaction.

RESULTSCompared with the EAE-M mice, (1) the neurological function scores were significantly decreased in BSYSC-treated mice on days 22 to 40 (P<0.01); (2) the inflammatory cells and demyelination in brains were reduced in BSYSC-treated EAE mice; (3) the protein expression of MBP was markedly increased in BSYSC-treated groups on day 18 and 40 respectively (P<0.05 or P<0.01); (4) the protein expression of Olig1 was increased in BSYSC (3.02 g/kg)-treated EAE mice on day 40 (P<0.01). Protein and mRNA expression of Olig2 was increased in BSYSC-treated EAE mice on day 18 and 40 (P<0.01).

CONCLUSIONThe effects of BSYSC on reducing demyelination and promoting remyelination might be associated with the increase of Olig1 and Olig2.

Animals ; Basic Helix-Loop-Helix Transcription Factors ; genetics ; metabolism ; Brain ; drug effects ; pathology ; ultrastructure ; Bromodeoxyuridine ; metabolism ; Capsules ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Encephalomyelitis, Autoimmune, Experimental ; drug therapy ; genetics ; pathology ; physiopathology ; Female ; Fluorescent Antibody Technique ; Mice, Inbred C57BL ; Myelin-Oligodendrocyte Glycoprotein ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Oligodendrocyte Transcription Factor 2 ; RNA, Messenger ; genetics ; metabolism

In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund's complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs.
Animals ; Brain/*pathology ; Disease Models, Animal ; Dog Diseases/*immunology ; Dogs ; Encephalitis/immunology/*veterinary ; Encephalomyelitis, Autoimmune, Experimental/immunology/*veterinary ; Female ; Fluorescent Antibody Technique/veterinary ; Immunization/veterinary ; Immunohistochemistry/veterinary ; Magnetic Resonance Imaging/veterinary ; Male ; Necrosis/immunology/*veterinary

OBJECTIVETo study the effects of Zuogui Pill (, ZGP) and Yougui Pill (, YGP) on the expressions of brain-derived neurotrophic factor (BDNF) and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) signaling of axonal regeneration in the Lewis rats with experimental autoimmune encephalomyelitis (EAE), in order to explore the possible mechanism of ZGP and YGP on promoting axonal regeneration.

METHODSThe rats were randomly divided into normal control (NC), model (MO), prednisone acetate (PA), ZGP and YGP groups. The EAE model of rat was established by injecting antigen containing myelin basic protein (MBP)68-86. The brain and spinal cord were harvested on the 14th and 28th day post-immunization (PI), the protein and mRNA expression of BDNF and PKA in the brain and spinal cord of rats were detected by Western blot analysis and real-time quantitative polymerase chain reaction (PCR), and the cAMP levels were detected by using enzyme-immunoassay method.

RESULTS(1) On the 28th day PI, the mRNA expression of BDNF in brain white matter and spinal cord of rats in ZGP and YGP groups were up-regulated, especially in YGP group (P<0.05 or P<0.01). (2) On the 14th day PI, the cAMP levels in brain white matters significantly increased in PA and YGP groups compared with MO group (P<0.05 or P<0.01), and the cAMP level in YGP group was higher than that in ZGP group (P<0.05). The cAMP level in spinal cord also significantly increased in YGP group compared with MO, PA and ZGP groups, respectively (P<0.01). (3) On the 14th day PI, the PKA expression in spinal cord of rats in ZGP group was significantly decreased compared with MO and YGP groups, respectively (P<0.05). (4) On the 28th day PI, there was a positive correlation between cAMP and PKA expression in the brain white matter of YGP rats.

CONCLUSIONSThe results suggest that ZGP and YGP may promote axonal regeneration by modulating cAMP/PKA signal transduction pathway, but the targets of molecular mechanism of ZGP may be different from those of YGP.

Animals ; Axons ; drug effects ; pathology ; Brain ; drug effects ; metabolism ; pathology ; Brain-Derived Neurotrophic Factor ; genetics ; metabolism ; Cyclic AMP ; metabolism ; Cyclic AMP-Dependent Protein Kinases ; genetics ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Encephalomyelitis, Autoimmune, Experimental ; drug therapy ; enzymology ; genetics ; Female ; Gene Expression Regulation ; drug effects ; Nerve Regeneration ; drug effects ; genetics ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Inbred Lew ; Signal Transduction ; drug effects ; genetics ; Spinal Cord ; drug effects ; metabolism ; pathology ; Tablets

OBJECTIVETo observe the pathological changes of axonal injury in a rat model of experimental allergic encephalomyelitis (EAE).

METHODSWith HE, luxol fast blue and Bielschowsky staining, the expression of APP, MBP, SMI-32 and MBP in the brain and spinal cord of EAE rats using double-labeling indirect immunofluorescence.

RESULTSExtensive cuffing lesions of inflammatory cell infiltrations were found in the brain and spinal cord of the rats, accompanied by multiple lesions of demyelination, axonal disarrangement with vesicular loss. SMI-32 staining identified numerous nonphosphorylated neurofilament, indicating the presence of axonal injury. Axonal oval bodies formed by APP accumulation were found in the white matters of the spinal cord 14 days after EAE, suggesting that neuraxial damage occurred in the early stage of EAE which was not synchronous with myelin loss.

CONCLUSIONDifferent levels of inflammation occur in different stages of EAE, and inflammatory cell infiltration is the most obvious at the peak of EAE. Axonal injury occurs in the early stage of EAE and progresses over the entire disease course.

Animals ; Axons ; pathology ; Brain ; pathology ; Encephalomyelitis, Autoimmune, Experimental ; pathology ; Female ; Rats ; Rats, Wistar ; Spinal Cord ; pathology

OBJECTIVETo study the pathological changes in the non-myelin sheath by observing histological damages to the neurofilament protein and apoptosis of neurons in rats with experimental autoimmune encephalomyelitis (EAE).

METHODSForty-eight Wistar rats were randomly divided into two groups: control and EAE (24 rats in each group). Behavioral changes were observed. Inflammation reactions and demyelination were observed by hematoxylin eosin staining and LOYEZ staining.The level of neurofilament was detected by immunohistochemistry. Apoptosis of the neuron in the spinal cord was detected by TUNEL.

RESULTSBehavioral and histological results confirmed that the model of EAE rats was prepared successfully. In the EAE group, typical morphological features of axonal damage (sparsed axonal density, axonal distortion, axonal transection and even axonal disappearance) were found from the seventh day after immunization and the morphological changes were the most obvious on the fourteenth day. Neurofilament density in the EAE group was significantly lower than in the control group (P<0.01) at 7, 14 and 21 days after immunization. The neuronal apoptosis index in the EAE group at 7, 14 and 21 days after immunization was significantly higher than in the control group (P<0.01).

CONCLUSIONSIn addition to inflammatory demyelination, axonal damage and neuronal apoptosis can be observed in the early stage of EAE. Pathological changes may be associated with neurological dysfunction.

Animals ; Apoptosis ; Axons ; pathology ; Encephalomyelitis, Autoimmune, Experimental ; pathology ; psychology ; Female ; Immunohistochemistry ; Myelin Sheath ; pathology ; Neurofilament Proteins ; analysis ; Neurons ; pathology ; Rats ; Rats, Wistar ; Spinal Cord ; pathology

OBJECTIVETo study the therapeutic efficacy of baicalin and its effect on apoptosis of inflammatory cells in spinal cords in Wistar rats with autoimmune encephalomyelitis (EAE).

METHODSForty-four rats were randomly divided into four groups: normal control group (control, n=10), EAE group (n=12), and two intervention groups with dexamethasone (DXM) or baicalin. Seven days after immunization, the two intervention groups were injected intraperitoneally with DXM (1 mg/kg) and baicalin (200 mg/kg) for 1 week, respectively. The spinal cords were removed 14 days after immunization, and stained with hematoxylin and eosin. MBP expression in spinal cords was detected by immunohistochemistry. The apoptosis of inflammatory cells in spinal cords was detected by TUNEL.

RESULTSThe weight gain rate in the untreated EAE and the DXM or baicalin intervention groups were significantly lower than that in the control group (P<0.05). The weight gain rate in the baicalin intervention group was significantly higher than that in the untreated EAE and the DXM intervention groups (P<0.05). The scores of neurological function in the two intervention groups were significantly higher than that in the untreated EAE group (P<0.05). DXM or baicalin treatment significantly increased the MBP expression compared with the untreated EAE group (P<0.05). The apoptosis of inflammatory cells increased more in the DXM and the baicalin intervention groups compared with the untreated EAE groups (P<0.05).

CONCLUSIONSBaicalin has protective effects against EAE in rats. It can promote the apoptosis of inflammatory cells in spinal cords.

Animals ; Apoptosis ; drug effects ; Dexamethasone ; therapeutic use ; Encephalomyelitis, Autoimmune, Experimental ; drug therapy ; pathology ; Female ; Flavonoids ; pharmacology ; therapeutic use ; In Situ Nick-End Labeling ; Rats ; Rats, Wistar

OBJECTIVETo study the molecular mechanism of Zuogui Pill (ZGP) and Yougui Pill (YGP) on axonal regeneration in rats with experimental autoimmune encephalomyelitis (EAE).

METHODSEAE rat model was established by bilateral rear pedes subcutaneous injection of antigen made by mixing myelin basic protein (MBP) and complete Freud's adjuvant (CFA) in the volume ratio of 1:1. The pathological changes of axonal injury and regeneration in the brain and the spinal cord were observed on the 14th (the acute stage) and the 28th day (the remission stage) after modeling, with hematoxylin-eosin (HE) staining, silver stain, and immunohistochemical staining. The rats treated with prednisone acetate were taken as controls.

RESULTSObservation under the light microscope with HE staining showed a sleeve-like change in rats' cerebrospinal parenchyma with inflammatory cell infiltration around the small vessels and neuronic denaturation, while silver staining showed excessive tumefaction and abscission of axon, and immunohistochemical analysis showed decreasing of nerve growth factor (NGF) expression at the acute stage of EAE, which was even more remarkable at the remission stage, showing significant difference as compared with the normal control (P<0.05). And the expressions of Nogo A, an axon growth inhibitor, and its receptor (Nogo-66 receptor, Ng R) were significantly higher than those in the normal control at the acute stage (P<0.01). However, after the intervention of ZGP and YGP, the pathological changes and axon damage in rats' brain and spinal cord were much more alleviated, and the NGF expression was significantly higher than that in the model group at the acute stage (P<0.05). The expression of NGF was even stronger during the remission stage, and a better effect was shown by YGP. As for Nogo A and Ng R expressions, they were significantly lower than those in the model group at the acute stage (P<0.05), but a better effect was shown by ZGP.

CONCLUSIONSZGP and YGP can prevent axonal injury and promote the axonal regeneration in rats of EAE, and the possible mechanism is to increase the expression of NGF and reduce the expression of Nogo A and its receptor. However, some differences are observed between the two Chinese preparations in their acting times and points, which provides a certain basis for revealing the modern connotation of the Chinese medicine theory on tonifying Shen ()-yin and Shen-yang.

Animals ; Axons ; drug effects ; metabolism ; pathology ; physiology ; Brain ; drug effects ; metabolism ; pathology ; Disease Models, Animal ; Drug Evaluation, Preclinical ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Encephalomyelitis, Autoimmune, Experimental ; drug therapy ; metabolism ; pathology ; GPI-Linked Proteins ; Male ; Myelin Proteins ; metabolism ; Nerve Growth Factor ; metabolism ; Nerve Regeneration ; drug effects ; Nogo Proteins ; Nogo Receptor 1 ; Rats ; Rats, Inbred Lew ; Receptors, Cell Surface ; Receptors, Peptide ; metabolism ; Research ; Signal Transduction ; drug effects ; Tablets

OBJECTIVETo explore the sensitivity of magnetic resonance contrast agent ultrasmall superparamagnetic iron oxide (USPIO) enhancement scan in detecting experimental allergic encephalopathy (EAE) lesions and the change of magnetic transfer of USPIO enhancement lesions in the animal model of EAE.

METHODSThe routine T1-weighted imaging, T2-weighted imaging, three dimensional T1 magnetic transfer, three dimensional T1 no magnetic transfer, Dimeglumine Gadopentetate injection (Gd-DTPA) enhancement, and USPIO enhancement scan were performed in 11 EAE rats and 10 control rats respectively. The sensitivity of USPIO and Gd-DTPA enhancement in detecting the lesions in EAE rats was calculated. Magnetic transfer ratio (MTR) of USPIO enhancement area for the first time in EAE rats and MTR of the same area of the last scan were calculated respectively. HE and myelin staining of brain tissues were performed.

RESULTSNo abnormally enhanced lesions were showed in EAE rats' brain in Gd-DTPA enhancement scan, while abnormally enhanced lesions were showed in 11 EAE rats' brain in USPIO enhancement scan. The MTR value of USPIO enhancement area for the first time was significantly different from MTR of the same area of the last scan in EAE rats (P < 0.05). Inflammation cells and demyelination lesions were found in USPIO enhancement area histopathologically. There were no positive findings in control rats.

CONCLUSIONSThe sensitivity of USPIO enhancement scan in detecting EAE lesions was high. Magnetic transfer imaging, together with USPIO enhancement scan, was helpful to determine the features of the EAE lesions.

Animals ; Contrast Media ; Dextrans ; Encephalomyelitis, Autoimmune, Experimental ; diagnosis ; pathology ; Female ; Guinea Pigs ; Image Enhancement ; methods ; Magnetic Resonance Imaging ; methods ; Magnetite Nanoparticles ; Random Allocation ; Rats ; Rats, Inbred Lew