Decreased muscle strength in adjuvant-induced rheumatoid arthritis animal model: A relationship to behavioural assessments.

Rheumatoid arthritis (RA) is an autoimmune disorder with unknown aetiology. Patients suffering from RA face persistent pain due to joint inflammation, and tissue destruction. Behavioural phenotyping is an approach to target the role of different behavioural traits associated with disease progression. The study aimed to assess behavioural patterns associated with decreased muscle strength in the adjuvant-induced rheumatoid arthritis animal model. The study was conducted on male Albino Wister rats (n = 30) [Control, Vehicle, and Disease groups]. After taking ethical approvals RA was induced by complete Freund's adjuvant (CFA) intradermally base of tail. The weight of animals, macroscopic analysis of inflammatory signs, and arthritic scores were measured weekly. Grip strength, ganglia-based movement, cataleptic activity, and motor-coordination-related behaviours were assessed among the groups. Radiographs and spleen index assay were performed followed by data analysis using one-way and two-way ANOVA (Analysis of Variance). A significant decrease in weight and an increase in arthritic scores among the diseased group was observed. Behavioural analyses confirmed that diseased animals had significantly decreased grip strength and increased cataleptic activity with less motor coordination. Radiographic images and spleen index assay confirmed the pattern of RA. Therefore, it can be suggested that the development of the disease animal model is an effective approach to identifying the disease progression and associated behavioural changes. Moreover, this prepared laboratory animal model may be utilised for pathway analyses to understand the key role of immune regulators and genetic insight into molecular pathways associated with acute and chronic phases of RA.

Hyperfunction variant rs708035 of interleukin 1 receptor-associated kinases 2 gene involved in the predisposition of leprosy infection.

BACKGROUND: Mycobacterium leprae (slow-growing bacteria) is the etiological agent for leprosy infection, which is a chronic granulomatous disease. Symptoms initiate with the loss of sensation in the affected areas, which can lead to severe injuries, cuts and burns. IRAK2 (interleukin-1 receptor-associated kinases 2) is reported to function in the regulation of the NFκB pathway. The frequency of the IRAK2 polymorphism (rs708035) was unknown in the Pakistani population. Therefore, the study was designed to identify the role of the rs708035 SNP (single nucleotide polymorphism) in susceptibility to leprosy. METHODOLOGY: The case-control study was designed, and participants were selected by Ridley-Jopling Classification. Blood samples from healthy individuals and patients were collected after ethical approval. Genomic DNA was extracted for the amplification of selected polymorphisms by tetra-primer amplification refractory mutation system polymerase chain reaction. The desired products were observed via agarose gel (2.5%) electrophoresis followed by data analysis using bioinformatics tools (SNP Stats and SHEsis) and statistical tests (odds ratio, OR, and chi square). RESULTS: The study revealed that the mutant genotype (TT) was found to be frequent among cases (22.80%) in comparison with the controls (1.66%). The SNP rs708035 was significantly associated with the progression of leprosy (χ2  = 17.62, p < 0.0001). The targeted SNP significantly increases the risk of leprosy 2.3 times (OR = 2.3119, 95% CI 1.2729-4.1989, p < 0.01). The genetic model also confirms the significant association of the A/T genotype with leprosy in the over-dominant model (OR = 2.83, 95% CI 1.16-6.89, p < 0.001). CONCLUSIONS: The study revealed a significant association of the targeted SNP with leprosy and provided baseline data regarding the association of rs708035. The current research could be utilized for the preparation of biomarkers by considering a larger sample size. HIGHLIGHTS: The patients suffering from leprosy faced various comorbidities, including hypertension and diabetes. The study reports for the first time a significant association of interleukin 1 receptor associated kinases 2 (IRAK2) single nucleotide polymorphism (SNP) rs708035 among the Pakistani population (Karachi). The current study provides baseline data to develop diagnostic biomarkers for early detection of leprosy.

Single nucleotide polymorphisms (rs3736228 and rs4988321) in low-density lipoprotein receptor-related protein-5 gene with predisposition to rheumatoid arthritis.

BACKGROUND: LRP5 (Lipoprotein Receptor 5) is one of the representatives of the low-density lipoprotein receptors family that play a crucial role in the process of bone homeostasis and bone remodeling. The role of LRP5 single nucleotide polymorphisms (SNPs) rs3736228 and rs4988321 has been associated with the susceptibility to osteoporosis and bone fracture. The frequency of mentioned LRP5 SNPs is unknown among RA (Rheumatoid Arthritis) patients. The case-control study was designed to determine the association of targeted SNPs among RA patients. METHODOLOGY: Patients were selected by ACR/EULAR 2010 criteria. After ethical approval blood samples of patients and healthy individuals were collected. DNA was extracted from the whole blood followed by amplification of the targeted region by T-ARMS PCR (Tetra-primer Amplification Refractory Mutation System) obtained product was observed on agarose gel electrophoresis. The data were analyzed by statistical and bioinformatic tools. RESULTS: It was observed that the SNPs rs3736228 and rs4988321 showed significant association with the risk of RA [χ2 = 44, p =< 0.001, O.R 95 % CI = 2.495, (1.865 âˆ¼ 3.337), p =< 0.001] and [χ2 = 85, p =< 0.001, O.R 95 % CI = 2.05, (1.571 âˆ¼ 2.69), p =< 0.001] respectively. Haplotypes AT, GC, and GT were found to be significantly associated with the risk of RA. Furthermore, both SNPs were in 40 % LD (Linkage Disequilibrium). CONCLUSIONS: The study revealed that SNPs rs3736228 and rs4988321 were significantly associated with the increased susceptibility to RA. The study serves as the baseline data considering targeted SNPs and their association with the progression of the disease. The study might be utilized for the development of potential biomarker for diagnostic purposes and in the precision medicine approach.

Multi-locus SNP analyses of interleukin 1 receptor associated kinases 2 gene polymorphisms with the susceptibility to rheumatoid arthritis.

BACKGROUND: The genetic polymorphisms (rs708035, rs3844283) of Interleukin-1 receptor associated kinases 2 (IRAK2) is involved in the NFκB regulatory pathway. The frequencies of IRAK2 gene are unknown in Pakistani population. Therefore, the study was designed to examine the association of targeted single nucleotide polymorphism(s) in IRAK2 gene of RA patients. METHODOLOGY: The study participants were selected by ACR/EULAR 2010 standards. After ethical approval, the blood samples of patients and healthy controls were collected for the extraction of DNA followed by the amplification of targeted polymorphism(s) via Tetra-primer Amplification Refractory Mutation System (T-ARMS PCR). Desired products were observed via agarose gel electrophoresis. RESULTS: The allele frequency of wild type A and C is frequent among patients and mutant T and G is frequent among controls. The rs708035 showed significant protective association while rs3844283 was found to be associated with risk of RA. Genetic model associations were applied to determine the role of genotypes. In combination analyses of alleles revealed AC haplotype was found to be associated with risk and TG provide protection against RA. Moreover, targeted SNPs were found to be in 61% Linkage Disequilibrium among the targeted population. CONCLUSIONS: Current study revealed the protective and risk association of targeted SNPs (rs708035, rs3844283). Study might be beneficial as it provides baseline data regarding targeted SNPs and their role in the disease progression. This could be served as potential biomarker for diagnostic purpose and effectively utilized in precision medicine approach.