Genetic polymorphisms of IL-1beta and IL-1 receptor antagonist in association with multiple sclerosis in Japanese patients

Therapeutic effect of combination vitamin D3 and siponimod on remyelination and modulate microglia activation in cuprizone mouse model of multiple sclerosis

Stimulation of remyelination is critical for the treatment of multiple sclerosis (MS) to alleviate symptoms and protect the myelin sheath from further damage. The current study aimed to investigate the possible therapeutic effects of combining vitamin D3 (Vit D3) and siponimod (Sipo) on enhancing remyelination and modulating microglia phenotypes in the cuprizone (CPZ) demyelination mouse model. The study was divided into two stages; demyelination (first 5 weeks) and remyelination (last 4 weeks). In the first 5 weeks, 85 mice were randomly divided into two groups, control (n = 20, standard rodent chow) and CPZ (n = 65, 0.3% CPZ mixed with chow for 6 weeks, followed by 3 weeks of standard rodent chow). At week 5, the CPZ group was re-divided into four groups (n = 14) for remyelination stages; untreated CPZ (0.2 ml of CMC orally), CPZ+Vit D3 (800 IU/kg Vit D3 orally), CPZ+Sipo (1.5 mg/kg Sipo orally), and CPZ+Vit D3 (800 IU/kg Vit D3) + Sipo (1.5 mg/kg Sipo orally). Various behavioral tasks were performed to evaluate motor performance. Luxol Fast Blue (LFB) staining, the expression level of myelin basic protein (MBP), and M1/M2 microglia phenotype genes were assessed in the corpus callosum (CC). The results showed that the combination of Vit D3 and Sipo improved behavioral deficits, significantly promoted remyelination, and modulated expression levels of microglia phenotype genes in the CC at early and late remyelination stages. These results demonstrate for the first time that a combination of Vit D3 and Sipo can improve the remyelination process in the cuprizone (CPZ) mouse model by attenuating the M1 microglia phenotype. This may help to improve the treatment of MS patients.

Relapsing-remitting multiple sclerosis: A profile of interleukine-1 gene cluster polymorphisms in Iraqi patients

In this case-control study, 68 relapsing-remitting multiple sclerosis (RRMS) patients and 133 control were genotyped for IL1A-889 (rs1800587), IL1B-511 (rs16944), IL1B+3962 (rs1143634), IL1R1pst11970 (rs2234650) and IL1RNmspa1 11,100 (rs315952) variants. Sequence-specific-primer-polymerase-chain-reaction was the genotyping method. Logistic regression analysis demonstrated protective effects of IL1B-511, IL1R1pst11970 and IL1RNmspa1 11,100 against MS incidence, while no association was found with IL1A-889 and IL1B+3962 variants. Allele frequencies showed no significant gender, medication or expanded disability status scale-associated variation. Haplotype analysis suggested 4.31-fold increased odds for MS in subjects with C-T-C-C-T haplotype of the respective loci. In conclusion, IL-1 gene variants influence MS susceptibility in Iraqi population.

Progesterone therapy induces an M1 to M2 switch in microglia phenotype and suppresses NLRP3 inflammasome in a cuprizone-induced demyelination mouse model

Demyelination of the central nervous system (CNS) has been associated to reactive microglia in neurodegenerative disorders, such as multiple sclerosis (MS). The M1 microglia phenotype plays a pro-inflammatory role while M2 is involved in anti-inflammatory processes in the brain. In this study, CPZ-induced demyelination mouse model was used to investigate the effect of progesterone (PRO) therapy on microglia activation and neuro-inflammation. Results showed that progesterone therapy (CPZ+PRO) decreased neurological behavioral deficits, as demonstrated by significantly decreased escape latencies, in comparison to CPZ mice. In addition, CPZ+PRO caused a significant reduction in the mRNA expression levels of M1-markers (iNOS, CD86, MHC-II and TNF-α) in the corpus callosum region, whereas the expression of M2-markers (Trem-2, CD206, Arg-1 and TGF-β) was significantly increased, in comparison to CPZ mice. Moreover, CPZ+PRO resulted in a significant decrease in the number of iNOS⁺ and Iba-1⁺/iNOS⁺ cells (M1), whereas TREM-2⁺ and Iba-1⁺/TREM-2⁺ cells (M2) significantly increased, in comparison to CPZ group. Furthermore, CPZ+PRO caused a significant decrease in mRNA and protein expression levels of NLRP3 and IL-18 (~2-fold), in comparison to the CPZ group. Finally, CPZ+PRO therapy was accompanied with reduced levels of demyelination, compared to CPZ, as confirmed by immunofluorescence to myelin basic protein (MBP) and Luxol Fast Blue (LFB) staining, as well as transmission electron microscopy (TEM) analysis. In summary, we reported for the first time that PRO therapy causes polarization of M2 microglia, attenuation of M1 phenotype, and suppression of NLRP3 inflammasome in a CPZ-induced demyelination model of MS.

IL2RA Allele Increases Risk of Neuromyelitis Optica in Southern Han Chinese

Background:

Neuromyelitis optica (NMO) and multiple sclerosis (MS) are chronic neuro-inflammatory diseases believed to arise from complex interactions between environmental and genetic factors. Recently, single nucleotide polymorphisms (SNPs) in interleukin (IL)-2 and -7 receptor alpha genes have been identified as novel susceptibility alleles for MS in genome-wide association studies. However, similar research on NMO is limited. We aimed to investigate the association of IL2RA SNPs rs2104286 and rs12722489 and IL7RA SNP rs6897932 with Southern Han Chinese NMO and MS patients.

Methods:

Frequencies of the three SNPs were examined in Southern Han Chinese mS cases (n=78), NMS cases (n=67) and controls (n=133) using sequencing-based typing.

Results:

The rs2104286G frequency in the IL2RA gene was significantly higher in NMO patients than in controls (puncorr=0.013, pcorr=0.026, OR:1.942, 95%CI:1.146-3.291).

Conclusion:

The rs2104286 G allele in IL2RA is present at higher frequencies in NMO patients than in healthy controls within a Southern Han Chinese population.

NLRP3 Inflammasome and MS/EAE

Inflammasomes are cytosolic sensors that detect pathogens and danger signals in the innate immune system. The NLRP3 inflammasome is currently the most fully characterized inflammasome and is known to detect a wide array of microbes and endogenous damage-associated molecules. Possible involvement of the NLRP3 inflammasome (or inflammasomes) in the development of multiple sclerosis (MS) was suggested in a number of studies. Recent studies showed that the NLRP3 inflammasome exacerbates experimental autoimmune encephalomyelitis (EAE), an animal model of MS, although EAE can also develop without the NLRP3 inflammasome. In this paper, we discuss the NLRP3 inflammasome in MS and EAE development.

Association of interleukin-1 gene polymorphisms with multiple sclerosis: a meta-analysis

BACKGROUND

Dysregulated levels of interleukin-1 (IL-1) were observed in patients with multiple sclerosis (MS). Previous studies have provided conflicting evidence implicating the IL-1 gene polymorphisms in MS risk.

METHODS

A meta-analysis of 16 case-control studies involving 3,482 cases and 3,528 controls was conducted to evaluate this association.

RESULTS

No association was found between the IL-1α -889 (rs1800587), IL-1α +4,845 (rs17561), IL-1β -511 (rs16944), IL-1β +3,953 (rs1143634), IL-1ra variable number tandem repeat (VNTR) polymorphisms and MS risk. However, in subgroup analyses for the IL-1ra VNTR polymorphism, we found that individuals carrying the 2 allele had a 32 % increased risk for bout-onset MS (relapsing remitting and secondary progressive MS) when compared to the LL homozygotes (OR = 1.32, 95 % CI = 1.06-1.66, P (z) = 0.014).

CONCLUSION

Common variants in the IL-1 region are not associated with MS risk but our data suggest that the IL-1ra VNTR polymorphism might be associated with bout-onset MS subtype.

VNTR polymorphism of human IL1RN in Chinese Han and She ethnic populations

Interleukin 1 receptor antagonist (IL-1Ra) is an important anti-inflammatory molecule encoded by the IL1RN gene. The polymorphism of IL1RN characterized by variable numbers of an 86 bp tandem repeat (VNTR) sequence in intron 2 has been described. Moreover, frequencies of the IL1RN alleles vary among different ethnics. In the present study, we analysed the IL1RN polymorphism in intron 2 in 256 Chinese Han and 252 Chinese She individuals. Four alleles including IL1RN*1, *2, *3 and IL1RN*4 were identified in this study. Data revealed that the distribution of the IL-1RN genotypes and allele was significantly different between the two Chinese populations (P < 0.001). Among them, 66.8% (171/256) and 86.5% (218/252) were homozygous for the allele IL-1RN*1 in Chinese Han and She individuals respectively. Homozygosity for allele IL-1RN*2 was only observed in Chinese Han with the percentage of 0.8% (2/256). Heterozygosity for IL-1RN*1/2, IL1RN*1/3 and IL1RN*1/4 was 30.9% (79/256), 0.4% (1/256) and 1.2% (3/256) in Chinese Han, whereas only heterozygosity for IL-1RN*1/2 was found in Chinese She (13.5%, 34/252). Frequencies of the most common allele IL-1RN*1 and IL-1RN*2 were 83.0% and 16.2% for Chinese Han and 93.3% and 6.7% for Chinese She respectively. The rare allele IL-1RN*3 and IL-1RN*4 was only observed in the Chinese Han population with the frequency of 0.2% and 0.6% respectively. Our findings suggested that the ethnic background plays an important role in IL-1Ra gene variation in different populations.

The genetics of clinical outcome in multiple sclerosis

Multiple sclerosis (MS) is a common inflammatory disease of the central nervous system (CNS), the clinical course of which varies considerably between patients. Genetic complexity and interactions with as yet unknown environmental factors have hindered researchers from fully elucidating the aetiology of the disease. In addition to influencing disease susceptibility, epidemiological evidence suggests that genetic factors may affect phenotypic expression of the disease. Genes that affect clinical outcome may be more effective therapeutic targets than those which determine susceptibility. We present in this review a comprehensive survey of the genes (both MHC- and non-MHC-related) that have been investigated for their role in disease outcome in MS. Recent studies implicating the role of the genotype and epistatic interactions in the MHC in determining outcome are highlighted.

Association of polymorphisms in CTLA-4, IL-1ra and IL-1beta genes with multiple sclerosis in Serbian population

We have investigated separate as well as combined influence of IL-1beta TaqI, IL-1ra VNTR and CTLA-4 + 49 A/G polymorphisms on susceptibility, clinical course and progression of MS in 162 Serbian patients. We found significant independent relative risk for MS susceptibility in noncarriers of IL-1ra allele 2 (OR = 2.2, CI = 1.3-3.7, p = 0.003) and CTLA-4 + 49 AA genotype (OR = 2.0, CI = 1.2-3.5, p = 0.01) as well as their combined effect (OR = 4.4, CI = 2.0-9.7, p = 0.0003). Our result supports the significant and combined effect of IL-1ra VNTR and CTLA-4 polymorphisms on MS justifying the need for further haplotype analysis in different populations.

Impact of a genetic polymorphism of the interleukin-1 receptor antagonist on technique survival in peritoneal dialysis patients

BACKGROUND/AIMS

There is a clear association between one allele of the interleukin-1 receptor-antagonist gene (IL-1RN) and inflammatory diseases in which IL-1 is implicated. We evaluated patient survival and technique survival of peritoneal dialysis (PD) patients, while analyzing independent risk factors, in a PD program. We also tested the association between IL-1RN polymorphism, patient survival and technique survival.

METHODS

We retrospectively evaluated 129 Japanese CAPD patients undergoing initial treatment in eight centers in Japan. Using PCR, IL-1RN genotype and allele frequencies were determined, and clinical and biochemical variables were recorded at the start of PD. The relation of patient survival or technique survival with IL-1RN polymorphism and those variables was analyzed with a multivariate Cox's proportional-hazard model.

RESULTS

The frequencies of IL-1RN*1/IL-1RN*1 and IL-1RN*1/IL-1RN*2 genotypes were 84.5 and 15.5%, respectively. Median patient survival was 37.0 months, and overall patient survival was 92.8 and 87.9% at 2 and 5 years, respectively. Age, cardiovascular disease and serum albumin were found to be independent predictors of patient survival. Median technique survival was 32 months. PD failure occurred in 37 patients, with technique survival rates of 92.0 and 72.7% at 2 and 5 years, respectively. Serum albumin, peritonitis and the presence of the IL-1RN*2 genotype were found to be independent predictors of technique survival.

CONCLUSION

Serum albumin was the strongest predictive factor for mortality and technique failure in PD. Technique failure was also affected by IL-1RN polymorphism in this patient population.

The interleukin-1 gene family in multiple sclerosis susceptibility and disease course

Multiple sclerosis (MS) is a chronic disease of presumed autoimmune origin with a considerable polygenic influence. We have previously observed that a specific allele combination in genes of the interleukin-1 (IL-1) family influenced the progression rate in MS. We have considerably expanded our patient population (492 MS patients and 228 controls). In the present study, we investigated the role of the IL-IA--889, IL-1B--511, IL-1B f3953 and IL-1RN VNTR gene polymorphisms in MS. In addition, we performed preliminary analyses on longitudinal magnetic resonance imaging (MRI) data. We found no associations between the polymorphisms and susceptibility to MS or clinical features. In addition, we observed no significant effect of the polymorphisms on brain or lesion volumes, Based on our data and those from the literature, one can conclude that there is currently no evidence to support a role for the IL-1 genes in MS.

C–C chemokine receptor 2 gene polymorphism in Japanese patients with multiple sclerosis

C-C chemokine receptor 2 (CCR2) is a receptor for chemoattractant protein-1 (MCP-1) and associated with infiltrating lymphocytes in chronic active multiple sclerosis (MS) lesions. To study the role of CCR2 gene in the development of MS, we investigated the CCR2-64I polymorphism in 122 MS patients and 112 healthy controls in a Japanese population. We also analysed the influence of CCR2-64I polymorphism on the clinical course, age at disease onset, and severity. The distribution of the CCR2-64I allele was significantly different between patients and controls (p=0.0187), and the 64I/64I homozygote was significantly less common in MS than in control. Logistic analysis, adjusted for HLA-DRB1*1501-positivity, revealed negative association between the CCR2-64I and MS (p=0.0204). There were no significant associations between CCR2 polymorphism and the clinical features of MS. Our results indicate that the presence of CCR2-64I allele seems to provide protection against the development of MS.

Genetic analysis of multiple sclerosis

Multiple sclerosis (MS) is a complex disease with a significant genetic contribution. Similar to other complex diseases, the genetic risk for MS results from a combination of many genetic variants which individually confer only modest effects. Here we review the results of the complementary genetic approaches of linkage and association in MS, highlighting the challenges of identifying loci of modest effect. We describe meta-analytical approaches that provide additional statistical power necessary for detecting such loci and further apply this approach to evaluate the association of a CTLA-4 variant with MS. Lastly, we review recent important advances in our understanding of the patterns of genetic variation in the human genome and speculate about how these advances will aid in future studies of the genetic causes of MS.

Polymorphisms of apolipoprotein E and Japanese patients with multiple sclerosis

The relation between apolipoprotein (APOE) gene polymorphisms and disease progression of multiple sclerosis (MS) is controversial. The present study was designed to investigate the relation between APOE gene polymorphisms and Japanese patients with MS. We analysed the frequencies of APOE gene polymorphisms in 135 MS patients and 134 healthy controls, using PCR-RFLP. The results showed no significant differences in the distribution of APOE gene polymorphisms between MS patients and controls. With regard to disease progression, there was no association between APOE gene polymorphisms and epsilon4 allele positivity and disease progression index (EDSS/ years). Furthermore, in patients with more than 10 years of disease onset, there were no significant differences between the frequencies of epsilon4 allele and patients with EDSS of more than 6. Although the low rate of epsilon4 allele in Japan should be taken into consideration, our results showed no relation between APOE gene polymorphisms and Japanese patients with MS.

Secretion of interleukin-1beta by astrocytes mediates endothelin-1 and tumour necrosis factor-alpha effects on human brain microvascular endothelial cell permeability

Evidence suggests that endothelin-1 (ET-1) plays an essential role in brain inflammation. However, whether ET-1 contributes directly to blood-brain barrier (BBB) breakdown remains to be elucidated. Using an in vitro BBB model consisting of co-cultures of human primary astrocytes and brain microvascular endothelial cells (BMVECs), we first investigated the expression of ET-1 by BMVECs upon stimulation with tumour necrosis factor (TNF)-alpha, which plays an essential role in the induction and synthesis of ET-1 during systemic inflammatory responses. Increased ET-1 mRNA was detected in the human BMVECs 24 h after TNF-alpha treatment. This was correlated with an increase in ET-1 levels in the culture medium, as determined by sandwich immunoassay. Both TNF-alpha and ET-1 increased the permeability of human BMVECs to a paracellular tracer, sucrose, but only in the presence of astrocytes. The increase in BMVEC permeability by TNF-alpha was partially prevented by antibody neutralization of ET-1 and completely by monoclonal antibody against IL-1beta. Concomitantly, TNF-alpha induced IL-1beta mRNA expression by astrocytes in co-culture and this effect was partially prevented by ET-1 antibody neutralization. In parallel experiments, treatment of human primary astrocytes in single cultures with ET-1 for 24 h induced IL-1beta mRNA synthesis and IL-1beta protein secretion in the cell culture supernatant. Taken together, these results provide evidence for paracrine actions involving ET-1, TNF-alpha and IL-1beta between human astrocytes and BMVECs, which may play a central role in BBB breakdown during CNS inflammation.

Genetic polymorphisms of osteopontin in association with multiple sclerosis in Japanese patients

Osteopontin (OPN) exhibits pleiotropic functions and abundant transcripts for OPN are present in brains of patients with multiple sclerosis (MS). The aim of this study was to investigate the role of OPN genes in the pathogenesis of MS. Polymorphisms at the 8090th, 9250th and 9583rd positions in OPN were detected by PCR-RFLP from DNAs of 116 MS Japanese patients and 124 healthy controls. The C/C genotype at the 8090th position in exon 6 was more prevalent in MS than in control (p<0.0001), and C allele was more prevalent in MS than in control (p<0.0001, OR=2.57, 95% CI=1.65-4.00). For the 9583rd position polymorphism in exon 7, patients with G/G genotype (age; 32.1+/-12.5 years, mean+/-S.D.) showed a later disease onset than G/A (age; 25.9+/-7.8 years, p=0.01) and A/A (age; 25.2+/-8.9 years, p=0.01) genotypes. There were no significant correlations between OPN gene polymorphisms and disease progression. Our results suggest that the 8090th polymorphism might be associated with susceptibility to MS, while the 9583rd polymorphism might be associated with age of onset of MS.

Multiple sclerosis in the Japanese population

Multiple sclerosis (MS) in Asian populations is characterised by the selective and severe involvement of the optic nerve and spinal cord as well as low prevalence rates. 15-40% of cases of MS in Japan are of this "opticospinal" type. This form of MS generally has a higher age at onset and a higher female to male ratio than conventional MS. Opticospinal MS is also characterised by frequent relapses, severe disability, few brain lesions visible on MRI, long lesions extending over many vertebral segments visible on spinal-cord MRI, pleocytosis and an absence of oligoclonal bands in the CSF, and a pronounced shift in the responses of T-helper-1 and T-cytotoxic-1 cells throughout relapse and remission phases. Conventional MS in Japanese people is, like MS in white people, associated with HLA-DRB1*1501, whereas opticospinal MS is associated with HLA-DPB1*0501. In Japanese people born after modernisation in the 1960s, the ratio of conventional to opticospinal MS has increased rapidly. Opticospinal MS is likely to have a distinct immune-mediated mechanism, which is not operative in conventional MS.

An assessment of the association between IL-2 gene polymorphisms and Japanese patients with multiple sclerosis

Interleukin-2 (IL-2) is a cytokine intimately involved with both the function and regulation of the immune system. Genetic analysis of experimental autoimmune encephalomyelitis (EAE) provides strong evidence supporting the candidacy of IL-2 as a susceptibility gene. We investigated the association of two single nucleotide polymorphisms (SNPs) at position -384 in the promoter region and +114 in the first exon of the IL-2 gene through a case-control study involving 113 Japanese patients with multiple sclerosis (MS) and 118 healthy controls. Our results showed no significant differences in the distribution of the two polymorphisms between MS patients and controls. Furthermore, no association was observed between IL-2 gene polymorphisms and clinical characteristics, such as clinical course and age at disease onset. Together, our findings suggest that IL-2 gene polymorphisms do not influence the susceptibility to MS or the clinical characteristics of MS in Japanese patients.

An examination of the association between beta2 adrenergic receptor polymorphisms and multiple sclerosis

In multiple sclerosis (MS), beta-adrenergic receptor densities on peripheral blood mononuclear cells are enhanced, while the astrocytes present in plaques lack beta2 adrenergic receptor (beta2AR) expression. This differentially altered expression suggests that beta2ARs may influence the pathogenesis of MS. In the present study, we investigated the association of polymorphisms of the beta2AR gene with the occurrence of MS. Our results showed no significant differences in the distribution of the polymorphisms between MS patients overall and control subjects. Furthermore, no association was observed between the presence of beta2AR gene polymorphisms and clinical characteristics, such as age at disease onset and disease severity. While a trend towards an increase of the Gly allele frequency in codon 16 was observed in the secondary-progressive MS, this result was not significantly different from that observed in relapsing-remitting MS patients or control subjects. Together, our findings suggest that the presence of beta2AR gene polymorphisms may be inconclusive in the susceptibility to MS or in the clinical characteristics of Japanese patients with MS and, therefore, need further studies.

The balance between IL-1 and IL-1Ra in disease

IL-1 is an important mediator of inflammation and tissue damage in multiple organs, both in experimental animal models of disease and in human diseases. The IL-1 family consists of two agonists, IL-1alpha and IL-1beta, two receptors, biologically active IL-1RI and inert IL-1RII, and a specific receptor antagonist, IL-1Ra. The balance between IL-1 and IL-1Ra in local tissues plays an important role in the susceptibility to and severity of many diseases. An allelic polymorphism in the IL-1Ra gene has been associated with a variety of human diseases primarily of epithelial and endothelial cell origin. This association may be secondary to an imbalance in the IL-1 system with enhanced production of IL-1beta and reduced production of the major intracellular isoform of IL-1Ra. Treatment of RA with daily subcutaneous injections of recombinant IL-1Ra protein has been shown to be efficacious. Gene therapy approaches with IL-1Ra are being evaluated for the treatment of RA and other human diseases.

Interleukin 1 genotypes in multiple sclerosis and relationship to disease severity

We studied the association between clinical outcome in MS and allelic variants single nucleotide polymorphisms (SNPs) of interleukin-1alpha (IL-1alpha), IL-1beta and a variable number tandem repeat (VNTR) in IL-1 receptor antagonist (IL-1RN). A total of 377 patients with MS were studied. Significant associations between IL-1 genotypes and clinical outcome were found using logistic regression after correction for gender, onset age and disease duration. The same trends were subsequently demonstrated in a second independent group of 67 primary progressive patients. Our results suggest that genetically determined immunomodulation mediated by IL-1 influences long-term prognosis in multiple sclerosis (MS).