SIRT1 -1400T>C Polymorphism (rs12778366) and metabolic-inflammatory variability in women with systemic lupus erythematosus: Perspectives for personalized nutrition

Abstract

Objectives

This study aimed to investigate the association between the SIRT1 -1400T>C polymorphism (rs12778366) and body composition parameters as well as inflammatory biomarkers in women with SLE.

This study aimed to investigate the association between the SIRT1 -1400T>C polymorphism (rs12778366) and body composition parameters as well as inflammatory biomarkers in women with SLE.

Methods

This exploratory study included 121 women diagnosed with SLE and followed at the Adult Lupus Outpatient Clinic of the Rheumatology Division, Hospital das Clínicas, Faculty of Medicine, University of São Paulo. Participants were stratified according to the TT, CT, and CC genotypes of the -1400T>C polymorphism. The evaluated parameters included body mass index (BMI), waist circumference (WC), absolute lean mass (LM), percentage of lean mass, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and disease activity assessed by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Data normality was assessed using the Shapiro–Wilk test. Parametric variables were analyzed using one-way ANOVA, whereas nonparametric variables were compared using the Kruskal–Wallis test. Statistical significance was set at P < 0.05. All study procedures were conducted following approval by the Research Ethics Committee of the Hospital das Clínicas, Faculty of Medicine, University of São Paulo (HC-FMUSP), under CAAE No. 86418824.6.0000.0068.

This exploratory study included 121 women diagnosed with SLE and followed at the Adult Lupus Outpatient Clinic of the Rheumatology Division, Hospital das Clínicas, Faculty of Medicine, University of São Paulo. Participants were stratified according to the TT, CT, and CC genotypes of the -1400T>C polymorphism. The evaluated parameters included body mass index (BMI), waist circumference (WC), absolute lean mass (LM), percentage of lean mass, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and disease activity assessed by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Data normality was assessed using the Shapiro–Wilk test. Parametric variables were analyzed using one-way ANOVA, whereas nonparametric variables were compared using the Kruskal–Wallis test. Statistical significance was set at P < 0.05. All study procedures were conducted following approval by the Research Ethics Committee of the Hospital das Clínicas, Faculty of Medicine, University of São Paulo (HC-FMUSP), under CAAE No. 86418824.6.0000.0068.

Results

No statistically significant differences were observed among genotypes for BMI (P = 0.802), WC (P = 0.252), LM (P = 0.094), percentage of lean mass (P = 0.629), CRP (P = 0.070), ESR (P = 0.088), or SLEDAI (P = 0.450). The TT genotype was the most prevalent (81.8%), followed by CT (9.9%) and CC (8.3%). Allelic frequencies were 86.8% for the T allele and 13.2% for the C allele.

No statistically significant differences were observed among genotypes for BMI (P = 0.802), WC (P = 0.252), LM (P = 0.094), percentage of lean mass (P = 0.629), CRP (P = 0.070), ESR (P = 0.088), or SLEDAI (P = 0.450). The TT genotype was the most prevalent (81.8%), followed by CT (9.9%) and CC (8.3%). Allelic frequencies were 86.8% for the T allele and 13.2% for the C allele.

Conclusion

The SIRT1 -1400T>C polymorphism (rs12778366) was not significantly associated with metabolic parameters, inflammatory biomarkers, or disease activity in women with SLE. Nevertheless, given the regulatory role of SIRT1 in metabolic and inflammatory pathways, rs12778366 remains a biologically relevant candidate variant for investigating the clinical and metabolic heterogeneity of SLE. The predominance of the TT genotype and the low frequency of variant genotypes (CT and CC) may have limited the statistical power of the analyses, highlighting the need for larger studies to better elucidate the functional impact of this polymorphism in SLE.

The SIRT1 -1400T>C polymorphism (rs12778366) was not significantly associated with metabolic parameters, inflammatory biomarkers, or disease activity in women with SLE. Nevertheless, given the regulatory role of SIRT1 in metabolic and inflammatory pathways, rs12778366 remains a biologically relevant candidate variant for investigating the clinical and metabolic heterogeneity of SLE. The predominance of the TT genotype and the low frequency of variant genotypes (CT and CC) may have limited the statistical power of the analyses, highlighting the need for larger studies to better elucidate the functional impact of this polymorphism in SLE.