Exploratory analysis of TNF promoter SNPs and their potential associations with sarcopenia components in older...

Considering the key role of inflammation in sarcopenia pathogenesis, we focused on tumor necrosis factor (TNF). We examined associations between TNF promoter single-nucleotide polymorphisms (SNPs; rs1799964, rs1799724, and rs361525), individually and as haplotypes, with serum TNF-α levels and sarcopenia in older Mexican adults.

This cross-sectional study included Mexican adults aged 70 years or older. Sarcopenia was defined using calf circumference as a proxy for muscle mass, plus grip strength and physical performance, according to the European Working Group on Sarcopenia in Older People (EWGSOP) criteria. Serum TNF-α was measured by enzyme immunoassay, SNPs were genotyped using TaqMan assays, and haplotypes were estimated using haplo.stats and HAPLOVIEW. Among 223 participants, 45 had sarcopenia. rs1799964 was associated with grip strength in the total sample (OR = 0.08, 95%CI = 0.01-0.86, p = 0.014) and with calf circumference in men (OR = 0.08, 95%CI = 0.01-0.96, p = 0.014). rs1799724 was associated with poor physical performance (OR = 1.88, 95%CI = 1.04-3.37, p = 0.032), as was the TTG haplotype (OR = 1.85, 95%CI = 1.10-3.11, p = 0.019). Serum TNF-α was inversely correlated with Physical Performance (rho= -0.142, p = 0.047).

Our findings suggest that TNF promoter SNPs may be associated with specific components of sarcopenia, but not with serum TNF-α levels or the presence of sarcopenia in older Mexican adults. These results are exploratory and should be interpreted with caution, highlighting the need for further research to confirm and clarify these associations.