Impact of the polymorphism in vitamin D receptor gene BsmI and the risk of systemic lupus erythematosus: an updated meta-analysis

Risk factors of systemic lupus erythematosus: an overview of systematic reviews and Mendelian randomization studies

BACKGROUND

The etiology of systemic lupus erythematosus is complex and incurable. A large number of systematic reviews have studied the risk factors of it. Mendelian randomization is an analytical method that uses genetic data as tool variables to evaluate the causal relationship between exposure and outcome.

OBJECTIVE

To review the systematic reviews and Mendelian randomization studies that focused on the risk factors of systemic lupus erythematosus and shed light on the development of treatments for its prevention and intervention.

METHODS

From inception to January 2022, we systematically searched MEDLINE (via PubMed) and Embase for related systematic reviews and Mendelian randomization studies. Extract relevant main data for studies that meet inclusion criteria. The quality of systematic reviews was assessed by using Assessment of Multiple Systematic Reviews 2 (AMSTAR-2). Finally, the risk factors are scored comprehensively according to the results' quantity, quality, and consistency.

RESULTS

Our study involved 64 systematic reviews and 12 Mendelian randomization studies. The results of systematic reviews showed that diseases (endometriosis, atopic dermatitis, allergic rhinitis), lifestyle (smoking, drinking, vaccination), and gene polymorphism influenced the incidence of systemic lupus erythematosus. The results of Mendelian randomization studies identified the role of disease (periodontitis, celiac disease), trace elements (selenium, iron), cytokines (growth differentiation factor 15), and gut microbiome in the pathogenesis of systemic lupus erythematosus.

CONCLUSION

We should pay attention to preventing and treating systemic lupus erythematosus in patients with endometriosis, celiac disease, and periodontitis. Take appropriate dietary supplements to increase serum iron and selenium levels to reduce the risk of systemic lupus erythematosus. There should be no excessive intervention in lifestyles such as smoking and drinking.

Impact of Vitamin D Receptor Gene Polymorphism on Systemic Lupus Erythematosus Susceptibility: A Pooled Analysis

Background: This study was designed to evaluate the influence of vitamin D receptor (VDR) gene polymorphisms on systemic lupus erythematosus (SLE) susceptibility. Methods: All eligible investigations were identified, the number of the various genotypes in the case and control groups were reviewed. A pooled analysis was performed using the Stata software. The study was carried out according to the Ethics Review Committee of The Third Xiangya Hospital, Central South University. Results: This meta-analysis included 19 studies. In our analysis, the VDR Apal polymorphism was correlated with SLE susceptibility in the overall population (AA vs. aa: odds ratio [OR] = 1.374, 95% confidence interval [CI]: 1.115-1.692, p = 0.003; AA + Aa vs. aa: OR = 1.342, 95% CI: 1.139-1.583, p < 0.01). The VDR Bsml and Apal polymorphisms were correlated with SLE susceptibility in Caucasian subjects (BB vs. Bb + bb: OR = 0.734, 95% CI: 0.593-0.909, p = 0.005; B vs. b: OR = 0.865, 95% CI: 0.760-0.983, p = 0.026; AA vs. aa: OR = 1.329, 95% CI: 1.016-1.740, p = 0.038). The VDR BsmI and FokI polymorphisms were correlated with SLE in African subjects (B vs. b: OR = 1.898, 95% CI: 1.458-2.470, p＜0.01; BB + Bb vs. bb: OR = 2.935, 95% CI: 1.944-4.430, p < 0.01; FF vs. Ff + ff: OR = 2.424, 95% CI: 1.673-3.512, p < 0.01; F vs. f: OR = 1.720, 95% CI: 1.417-2.087, p < 0.01; FF vs. ff: OR = 3.154, 95% CI: 2.083-4.774, p < 0.01; FF + Ff vs. ff: OR = 1.803, 95% CI: 1.363-2.384, p < 0.01). In addition, the VDR Apal polymorphism was correlated with SLE in female subjects (AA vs. aa: OR = 1.392, 95% CI: 1.049-1.849, p = 0.022) when stratified by gender. But there was no association between the VDR TaqI polymorphism and SLE susceptibility in our analysis. Conclusions: The VDR Apal polymorphism was associated with SLE susceptibility in general populations; in addition, Apal polymorphism was associated with SLE in female subjects. The VDR Bsml gene polymorphism was correlated with SLE susceptibility in Caucasian and African populations, whereas the VDR FokI polymorphism was correlated with SLE in African populations. But there was no association between the VDR TaqI polymorphism and SLE susceptibility in our analysis.

Vitamin D status in patients with systemic lupus erythematosus (SLE): A systematic review and meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease where chronic inflammation and tissue or organ damage is observed. Due to various suspected causes, inadequate levels of vitamin D (a steroid hormone with immunomodulatory effects) has been reported in patients with SLE, however, contradictory.

AIMS

The aim of this systematic review and meta-analysis was to evaluate the serum levels of vitamin D in patients with SLE in compared to healthy controls.

METHODS

PubMed, SCOPUS, ScienceDirect and Google Scholar electronic databases were searched systematically without restricting the languages and year (up to March 2, 2019) and studies were selected based on the inclusion criteria. Mean difference (MD) along with 95% confidence intervals (CI) were used and the analyses were carried out by using a random-effects model. Different subgroup and sensitivity analyses were conducted. Study quality was assessed by the modified Newcastle-Ottawa Scale (NOS) and publication bias was evaluated by a contour-enhanced funnel plot, Begg's and Egger's tests.

RESULTS

We included 34 case-control studies (2265 SLE patients and 1846 healthy controls) based on the inclusion criteria. Serum levels of vitamin D was detected significantly lower in the SLE patients than that in the healthy controls (MD: -10.44, 95% CI: -13.85 to -7.03; p < .00001). SLE patients from Asia (MD: -13.75, 95% CI: -21.45 to -6.05; p = .0005), South America (MD: -3.16, 95% CI: -4.62 to -1.70; p < .0001) and Africa (MD: -16.15, 95% CI: -23.73 to -8.56; p < .0001); patients residing below 37° latitude (MD: -11.75, 95% CI: -15.79 to -7.70; p < .00001); serum vitamin D during summer season (MD: -7.89, 95% CI: -11.70 to -4.09; p < .0001), patients without vitamin D supplementation (MD: -15.57, 95% CI: -19.99 to -11.14; p < .00001) or on medications like hydroxychloroquine, corticosteroids or immunosuppressants without vitamin D supplementation (MD: -16.46, 95% CI: -23.86 to -9.05; p < .0001) are in higher risk in presenting inadequate serum levels of vitamin D. The results remained statistically significant from different sensitivity analyses which represented the robustness of this meta-analysis. According to the NOS, 91.2% of the studies were considered as of high methodological quality (low risk of bias). No significant publication bias was detected from contour-enhanced and trim and fill funnel plots or Begg's test.

CONCLUSION

Inadequate levels of serum vitamin D is significantly high in patients with SLE compared to healthy subjects, therefore, vitamin D supplementation with regular monitoring should be considered as part of their health management plans.

Oxidative stress and vitamin D receptor BsmI gene polymorphism in Egyptian children with systemic lupus erythematosus: a single center study

Systemic lupus erythematosus (SLE) is an autoimmune disease with unknown exact etiology. Vitamin D receptor gene ( VDR) and oxidative stress play important roles in the pathogenesis of SLE. Here we investigated the genotypes and allelic frequencies of VDR BsmI polymorphism as well as their relationship with oxidative stress markers in Egyptian SLE children. We conducted a cross-sectional comparative study at Mansoura University Children's Hospital, Egypt from 2014 to 2018 including 100 SLE children and 100 controls. We investigated both groups for VDR BsmI polymorphism using polymerase chain reaction. Oxidative stress was assessed using malondialdehyde, glutathione S-transferase, superoxide dismutase, catalase and total antioxidant capacity. BB genotype frequency was found to be significantly higher in the SLE group ( p = 0.04, odds ratio (95% confidence interval) = 2.5 (1.01–5.9)). However, VDR B allele and b allele showed insignificant differences between SLE patients and controls ( p = 0.36, odds ratio (95% confidence interval) = 1.2 (0.8–1.8)). Lower levels of glutathione S-transferase, superoxide dismutase and total antioxidant capacity were found in the SLE group with statistically significant differences as regards glutathione S-transferase and superoxide dismutase ( p < 0.001). Serum malondialdehyde and catalase levels were significantly higher in the SLE group ( p < 0.001). No significant differences were found between VDR BsmI polymorphism (genotypes and alleles) and oxidative stress markers in the SLE group. In conclusion, BB genotype of VDR BsmI polymorphism is associated with an increased risk of SLE among Egyptian children. Oxidative stress may contribute in pathogenesis of SLE but is not associated with VDR BsmI polymorphism.

Vitamin D, Inflammation and Immunity: Review of Literature and Considerations on Recent Translational and Clinical Research Developments

The most relevant and recent literature findings linking exposure to sunlight, Vitamin D (VD), inflammation and immune system in health and disease, are reviewed.

Reduced sunlight exposure determined hypo-vitaminosis D to be common among patients or even healthy subjects, especially at higher latitudes. Numerous studies support the hypothesis that VD insufficiency could contribute to the higher autoimmune diseases incidence in the same geographic areas.

In the present review, the ways in which VD was reported to influence immune system, contributing to organism homeostasis or disease development are addressed. In fact, some of the hormone activities were recognised to determine stimulation or inhibition of immune system components.

Several diseases, where an association with VD deficiency was studied, are summarised. Finally, the rationale for optimization of substitutive/additive therapy with VD analogues and the last innovations regarding these drugs are mentioned.

A population association study of vitamin D receptor gene polymorphisms and haplotypes with the risk of systemic lupus erythematosus in a Chinese population

The aim of the study is to investigate the association of vitamin D receptor (VDR) gene polymorphism, additional gene-gene interaction, and haplotype combination with systemic lupus erythematosus (SLE) risk. Pairwise linkage disequilibrium (LD) analysis was conducted using SNPstats. The association between four SNPs within VDR gene and SLE risk was investigated by logistic regression. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the interaction among four SNPs. Four SNPs within VDR gene were selected for genotyping in this study, including rs2228570, rs1544410, rs7975232, and rs731236. The T allele of rs2228570 and the G allele of the rs1544410 were associated with increased MM risk, adjusted ORs (95%CI) were 1.61(1.25-2.11) and 1.78 (1.34-2.23), respectively. GMDR analysis suggested a significant two-locus model (P = 0.0010) involving rs1544410 and rs2228570, and in this model, the cross-validation consistency was 10/10, and the testing accuracy was 62.70%. The haplotype analysis indicated that the most common haplotype was rs1544410-A and rs7975232-G haplotype, the frequencies of which were 0.4701 and 0.5467 in case and control group. Haplotype containing the rs1544410-G and rs7975232-T alleles were associated with increased SLE risk, OR (95%CI) = 2.08 (1.47-2.72), P < 0.001. We found that rs2228570 and rs1544410 within VDR gene, their interaction and haplotype containing the rs1544410-G and rs7975232-T alleles were all associated with increased SLE risk.

Vitamin D receptor FokI, TaqI, and ApaI polymorphisms and susceptibility to systemic lupus erythematosus: an updated meta-analysis

This study aimed to explore whether vitamin D receptor (VDR) polymorphisms are associated with susceptibility to systemic lupus erythematosus (SLE). Meta-analyses were conducted to determine the associations between the VDR FokI, TaqI, and ApaI polymorphisms and SLE in all subjects and each ethnic group. A total of 12 studies were considered in the meta-analysis, which involved 1974 patients and 2506 controls. Meta-analysis of the VDR FokI polymorphism showed no association between SLE and the FokI F allele in all study subjects (OR = 1.047, 95% CI = 0.781-1.403, p = 0.758). However, the meta-analysis showed a significant association between SLE and the VDR FokI F allele in the Arab population (OR = 1.721, 95% CI = 1.417-2.088, p < 0.001). Analysis using the recessive and dominant models and homozygote contrast showed the same pattern for the VDR FokI F allele in Europeans, Asians, and Arabs. This meta-analysis showed that polymorphisms in VDR FokI, TaqI, and ApaI are not associated with SLE susceptibility in overall, European and Asian populations. However, the VDR FokI polymorphism is associated with SLE susceptibility in the Arab population.

Association of vitamin D receptor BsmI rs1544410 and ApaI rs7975232 polymorphisms with susceptibility to adolescent idiopathic scoliosis: A systematic review and meta-analysis

BACKGROUND

AIS is the most common spinal deformity disease, yet its etiology remains uncertain. Significant associations have been found between AIS risk and vitamin D receptor (VDR) gene polymorphisms; however, some of these results are controversial. The aim of this study was to determine whether VDR BsmI rs1544410 and ApaI rs7975232 polymorphisms are correlated with AIS.

METHODS

Databases, including PubMed, EMBASE, Web of Science, the Cochrane Library, the Chinese Biomedical Literature Database, and the Wanfang Database, were systematically searched, and eligible case-control studies that explored the association of VDR (BsmI and ApaI) and the susceptibility to AIS were selected. The pooled odds ratio (OR) with 95% confidence interval (95% CI) was calculated to assess the associations, and subgroup meta-analyses were performed according to the ethnicity of the study population.

RESULTS

A total of 5 studies with 717 cases and 554 controls fulfilled the inclusion criteria after assessment by 2 reviewers. Generally, significant correlations were found between the BsmI polymorphism and AIS risk in overall populations and in Asian populations (overall population: B vs b: OR = 2.12, 95% CI = 1.21-3.75, P = .009; BB vs bb: OR = 3.38, 95% CI = 1.08-10.57, P = .036; Bb vs bb: OR = 2.50, 95% CI = 1.29-4.82, P = .006; BB/Bb vs bb: OR = 2.71, 95% CI = 1.31-5.63, P = .007; Asian population: B vs b: OR = 2.42, 95% CI = 1.27-4.61, P = .007; BB vs bb: OR = 4.09, 95% CI = 1.03-16.22, P = .045; Bb vs bb: OR =  2.94, 95% CI = 1.42-6.10, P = .004; BB/Bb vs bb: OR = 3.23, 95% CI = 1.42-7.35, P = .005). There was no significant association observed in Caucasian populations (all P > .05). With regard to the ApaI polymorphism, we found that it significantly decreased the risk of AIS (Aa vs AA: OR = 0.43, 95% CI = 0.24-0.77, P = .004; Aa/aa vs AA: OR = 0.52, 95% CI = 0.30-0.91, P = .023); however, we could not draw a definitive conclusion for Caucasian populations, as no studies have been conducted in this group to determine the role of the VDR ApaI polymorphism in AIS etiology and development.

CONCLUSION

VDR BsmI was significantly associated with AIS susceptibility in the overall and Asian populations, while the VDR ApaI polymorphism only played a key role in AIS etiology and development in Asian populations.

Association of polymorphic variants of PTPN22, TNF and VDR systems in children with lupus nephritis: a study in trios of Colombian families

Introducción. El lupus eritematoso sistémico es una enfermedad autoinmune cuya gravedad varía según la raza, género y edad de aparición. Esta disparidad también se observa en los marcadores genéticos asociados con la enfermedad presentes en los genes PTPN22, VDR y TNF. La estratificación genética que presentan las diferentes poblaciones en el mundo puede estar influyendo dicha variabilidad.Objetivo. Analizar la asociación y heredabilidad de variantes genéticas de los genes PTPN22, VDR y TNF con nefritis lúpica pediátrica (NLp) en familias colombianas.Materiales y métodos. Se realizó un estudio basado en familias con 46 tríos (caso/padre y madre). Se genotipificaron las variantes rs2476601 de PTPN22; rs361525 y rs1800629 de TNF; TaqI [rs731236], ApaI [rs7975232], BsmI [rs1544410] y FokI [rs2228570] de VDR mediante qPCR. Se estimó el efecto de la sobretransmisión del alelo de riesgo de padres a hijos y el desequilibrio de ligamiento de los loci VDR y TNF.Resultados. Se observó que el alelo A de rs2476601 en PTPN22 se distribuyó en el 8,69 % [n=16] de los padres mientras que en los casos es de 19,5 % [n=18] al igual que es sobretransmitido de padres a hijos 17 veces más con relación al alelo G (p=0,028). Los polimorfismos de TNF y VDR no se mostraron en desequilibrio de transmisión. Las variantes TaqI, ApaI y BsmI del VDR se mostraron en desequilibrio de ligamiento.Conclusión. Estos hallazgos muestran una asociación del polimorfismo rs2476601 de PTPN22 con NLp debido a su sobretransmisión en el grupo de familias estudiadas.

Association between killer cell immunoglobulin-like receptor (KIR) polymorphisms and systemic lupus erythematosus (SLE) in populations: A PRISMA-compliant meta-analysis

BACKGROUND

Recently, a growing number of studies show that the killer cell immunoglobulin-like receptor (KIR) gene polymorphisms may play a role in the systemic lupus erythematosus (SLE) susceptibility. Nonetheless, the results were inconsistent. Thus, a meta-analysis was carried out by integrating multiple research to clarify the association between KIR polymorphisms and SLE susceptibility.

METHODS

The Web of Science, Embase (Ovid), PubMed, Elsevier Science Direct, the Chinese Biomedical Database and CNKI, Wanfang databases (last search was updated on May 15, 2016) were systematically searched to select studies on addressing the association between the KIR polymorphisms and susceptibility to SLE in populations. The odds ratio (OR) with 95% confidence interval (95% CI) was calculated.

RESULTS

A total of 10 published case-control studies involving 1450 SLE patients and 1758 controls were available for this meta-analysis. Results suggested that KIR2DL1 might be a risk factor for SLE (OR 2DL1 =1.047, 95% CI=1.011-1.083) in all subjects. The KIR2DL3, KIR2DL5 were identified as protective factors for SLE in Asian populations (OR2DL3= 0.215, 95% CI = 0.077-0.598; OR2DL5 = 0.588, 95% CI = 0.393-0.881), but not in Caucasians.

CONCLUSIONS

The meta-analysis results suggested that 2DL1 might be a potential risk factor and 2DL3, 2DL5 might be protective factors for SLE in Asians but not in Caucasians.