Mannose-binding lectin polymorphisms and rheumatoid arthritis: A short review and meta-analysis

Rutin-loaded chitosan nanoparticles alleviated Freund's adjuvant induced rheumatoid arthritis via modulating oxidative stress and inflammatory parameters in Wistar rats

Rheumatoid arthritis (RA) is the most common chronic inflammatory disease, primarily affecting the joints and with stromal tissue dysregulation causing chronic inflammation and joint destruction. Rutin is a natural flavonoid with potential therapeutic properties in chronic destructive conditions including rheumatoid diseases. In this study, the protective effects of rutin nanoformulation in an animal model of rheumatoid arthritis caused by Freund's complete adjuvant (FCA) were investigated. Sixty male rats were randomly divided into ten groups including normal, negative control, prednisolone 10 mg/kg (positive control), 3 doses of rutin (15, 30, 45mg/kg), rutin nanoparticles (15, 30, 45 mg/kg), and nanoparticle without rutin, for 28 days. Different behavioral parameters including the open field test, acetone drop test, hot plate test, Von Frey test, and inclined plane test were evaluated. Serum levels of glutathione (GSH), catalase, and nitric oxide as well as histopathological analyses were measured in different groups. Also, matrix metalloproteinase (MMP)-2 and MMP-9 activity were appraised by gelatin zymography. The injection of FCA prolonged the rats' immobility duration in comparison to the control group. Rheumatoid arthritis induction also increased nitric oxide and decreased GSH and catalase levels, while these effects were reversed in the groups that received nanoparticles containing rutin and prednisolone. Rutin nanoparticles suppressed MMP-9 and activated MMP-2. Also, this rutin drug delivery system plays a significant role in the improvement of histopathological symptoms. Considering the improvement of behavioral and tissue symptoms and the modulation of the level of inflammatory cytokines, nanoparticles containing rutin can be proposed as a suitable approach in the management of patients with rheumatoid arthritis.

Genome-Wide Detection and Analysis of Copy Number Variation in Anhui Indigenous and Western Commercial Pig Breeds Using Porcine 80K SNP BeadChip

Copy number variation (CNV) is an important class of genetic variations widely associated with the porcine genome, but little is known about the characteristics of CNVs in foreign and indigenous pig breeds. We performed a genome-wide comparison of CNVs between Anhui indigenous pig (AHIP) and Western commercial pig (WECP) breeds based on data from the Porcine 80K SNP BeadChip. After analysis using the PennCNV software, we detected 3863 and 7546 CNVs in the AHIP and WECP populations, respectively. We obtained 225 (loss: 178, gain: 47) and 379 (loss: 293, gain: 86) copy number variation regions (CNVRs) randomly distributed across the autosomes of the AHIP and WECP populations, accounting for 10.90% and 22.57% of the porcine autosomal genome, respectively. Functional enrichment analysis of genes in the CNVRs identified genes related to immunity (FOXJ1, FOXK2, MBL2, TNFRSF4, SIRT1, NCF1) and meat quality (DGAT1, NT5E) in the WECP population; these genes were a loss event in the WECP population. This study provides important information on CNV differences between foreign and indigenous pig breeds, making it possible to provide a reference for future improvement of these breeds and their production performance.

Association of the Mannose-Binding Lectin 2 BB Genotype with COVID-19-Related Mortality

Mannose-binding lectin (MBL) is crucial in first-line immune defenses. There are still many unknown factors regarding the mechanisms causing variability in the clinical course of coronavirus disease 2019 (COVID-19). In Japan, there have been few reports to date regarding the association between MBL and COVID-19. It has been demonstrated that the MBL2 gene B variant at codon 54 (rs1800450) is associated with variabilities in the clinical course of COVID-19. We aimed to investigate how the level of serum MBL and the codon 54 variant of MBL (rs1800450) affect the disease severity of COVID-19. A total of 59 patients from the fourth wave and 49 patients from the fifth wave in Japan were analyzed based on serum MBL levels using ELISA and the genotype of MBL2 codon 54 using PCR reaction. There was no significant association between serum MBL levels and age. MBL2 genotype was independent of age, there was no significant difference in different COVID-19 severities, MBL genotypes, and serum MBL levels. Binary logistic regression analysis to identify predisposing factors for severe COVID-19 symptoms demonstrated that patients with the BB genotype had a higher risk of death from COVID-19. Our results quantitatively demonstrated that the BB genotype might be a factor associated with death from COVID-19.

Effect of mannose-binding lectin gene polymorphisms on the risk of rheumatoid arthritis: Evidence from a meta-analysis

BACKGROUND

The effect of mannose-binding lectin (MBL) gene polymorphisms on susceptibility of rheumatoid arthritis (RA) were evaluated in ethnically different populations, whereas the results were always inconsistent.

MATERIALS AND METHODS

Fourteen articles involving 36 datasets were recruited to evaluate the association between MBL gene polymorphisms and rheumatoid arthritis in a meta-analysis. The random or fixed effect models were used to evaluate the pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CIs).

RESULTS

Stratified analysis by ethnicities was conducted and the result revealed that rs1800450 (T vs C, OR = 1.32, 95% CI: 1.04-1.67, P < .05) and MBL-A/O (T vs C, OR = 1.20, 95% CI: 1.08-1.34, P < .001) were strongly associated with RA in Brazilian populations. In addition, the significant relationship between rs11003125 (T vs C, OR = 1.16, 95% CI: 1.06-1.26, P < .05) with RA were also observed in East Asian populations. Meanwhile, the inverse associations between rs5030737 with RA in East Asians and rs1800450 with RA in Indians were acquired. However, no association between any MBL polymorphism with RA susceptibility was confirmed in Caucasians.

CONCLUSIONS

The structural polymorphisms in exon 1 of MBL gene may significantly contribute to susceptibility and development of RA in Brazilian and Indian populations, whereas the functional polymorphisms in the promoter region were more likely to associate with RA in East Asians.

The ambiguous role of mannose-binding lectin (MBL) in human immunity

Mannose-binding lectin (MBL) and lectin complement pathway have become targets of increasing clinical interest. Many aspects of MBL have been recently explored, including the structural properties that allow it to distinguish self from non-self/altered-self structures. Experimental evidences have declared the additional 5′- and 3′-variants that in amalgamation with well-known secretor polymorphisms change MBL function and concentration. Moreover, the current review highlights the differential behavior of MBL on exposure with extra/intracellular pathogens and in autoimmune diseases, stressing the fact that “high MBL levels can increase diseases susceptibility,” a paradox that needs justification. Attributable to these discrepancies, no absolute level of MBL deficiency could be defined so far and thus must be interpreted for specific diseases through case–control population-specific designs. Overall, it is evident that further research is needed about MBL and the lectin pathway of complement. Particularly, the transformative role of MBL over evolution is of interest and its role with regard to pathogenesis of different diseases and potential therapeutic targets within the respective pathways should be further explored. Apart from this, it is necessary to adopt an extensive locus-wide methodology to apprehend the clinical significance of MBL2 polymorphisms in a variety of infectious diseases by the future studies.

C-type lectins in immunity and homeostasis

The C-type lectins are a superfamily of proteins that recognize a broad repertoire of ligands and that regulate a diverse range of physiological functions. Most research attention has focused on the ability of C-type lectins to function in innate and adaptive antimicrobial immune responses, but these proteins are increasingly being recognized to have a major role in autoimmune diseases and to contribute to many other aspects of multicellular existence. Defects in these molecules lead to developmental and physiological abnormalities, as well as altered susceptibility to infectious and non-infectious diseases. In this Review, we present an overview of the roles of C-type lectins in immunity and homeostasis, with an emphasis on the most exciting recent discoveries.

Cardiovascular risk and mannose binding lectin in patients with rheumatoid arthritis from southern Brazil

BACKGROUND

Mannose binding lectin (MBL) appears to be involved in susceptibility to rheumatoid arthritis (RA), in the inflammatory process and in the genesis of atherosclerotic disease.

OBJECTIVE

To study the association of MBL serum levels and its genotypic variation with carotid arteries intimal thickness (IMT) in RA patients from Southern Brazil.

METHODS

MBL serum levels, MBL2 genotyping and IMT were investigated in 90 RA patients along with their demographic, clinical and laboratory profile. MBL levels and MBL2 genotyping were evaluated in 90 healthy controls.

RESULTS

A significant lower MBL serum concentration was observed in patients with RA in relation to controls (528 ng/mL vs 937.5 ng/mL, p = 0.05, respectively). The median IMT in RA patients was 0.59 mm (0.51 to 0.85 mm). There was no correlation between levels of MBL with disease activity, erythrocyte sedimentation rate, autoantibodies presence or IMT (p = NS). A weak and negative correlation was found between MBL and CRP levels (Rho = -0.24; p = 0.02;). The MBL2 variant at codon 54 (variant B) and HYPA haplotype were the most frequently observed in the RA sample (67.5% and 31.7%). MBL2 wild type (A/A) were associated with lower IMT when compared with heterozygotes (A/O; p = 0.04) and low producers (O/O; p = 0.05). In addition, high producers genotypes had lower levels of CRP when compared with medium (p = 0.04) or with low producers (p = 0.05).

CONCLUSION

RA patients had lower MBL levels than controls. MBL were negatively associated with CRP serum levels; low MBL genotypes producers increased thickness of the IMT than high producers.