Abstract:The convenient determination of methylsulfonylmethane (MSM) for a commercially available dietary supplement was developed using gas chromatography (GC)-flame ionization detector (FID). Chromatography was performed on a capillary column (0.32 mm I.D × 30 m, 0.25 µm) coated with dimethylpolysiloxane using diethylene glycol methyl ether as an internal standard. The performance characteristics of GC were evaluated in terms of selectivity, linearity, precision, accuracy, recovery, limit of detection (LOD) and limit of quantification (LOQ). The calibration curve was highly linear (the coefficient of determination: 0.9979) within the concentration range of 10.0~800.0 µg/mL for MSM. The recoveries for three fortified concentrations were 96.7~97.1%, 96.6~97.3% and 96.8~97.2%, respectively. The LOD and LOQ of the method were 0.29 µg/mL and 0.97 µg/mL, respectively. All obtained results were acceptable according to the guidelines of the Association of Official Analytical Chemists for dietary supplements. Thus, the validated analytical method using the GC-FID system is suitable for the determination of MSM in dietary supplement formulations for quality control.

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The prevalence of type 2 diabetes mellitus (T2DM) is increasing worldwide. T2DM is one of the most common types of diabetes and is caused by increased insulin resistance and reduced insulin secretion. Peroxisome proliferator-activated receptor γ coactivator 1 alpha (PPARGC1A) is a master modulator of mitochondrial biogenesis and of gluconeogenesis in liver. In this study, we analyzed genetic polymorphisms of PPARGC1A gene in a middle-aged Korean population with T2DM. Using the genotype data of 736 T2DM cases and 4544 healthy controls obtained from the Korean Association Resource (KARE), we analyzed genetic correlations between single nucleotide polymorphisms (SNPs) of PPARGC1A and T2DM. Fifteen SNPs of PPARGC1A demonstrated a statistically significant association with T2DM. Of these, rs10212638 exhibited the strongest correlation with T2DM (P-value=0.015, OR=1.29, CI=1.05∼1.59), and the minor G allele of PPARGC1A increased the risk of T2DM. This is the first study to report a significant association between genetic polymorphisms in PPARGC1A and T2DM and suggests that SNPs of PPARGC1A display genetic correlations to the etiology of T2DM.

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