The Association of Cysteine with Obesity, Inflammatory Cytokines and Insulin Resistance in Hispanic Children and Adolescents

Abstract

ContextPlasma total cysteine (tCys) independently relates to fat mass in adults. Dietary cyst(e)ine promotes adiposity and decreases glucose tolerance in some rodent models, but alleviates insulin resistance in others.ObjectiveTo investigate whether the association of tCys with body fat extends to children at particular risk of obesity, and whether tCys is associated with insulin resistance and obesity-associated inflammation.MethodsWe explored the cross-sectional relations of fasting plasma tCys and related metabolites with body composition measured by dual-energy X-ray absorptiometry in 984 Hispanic children and adolescents aged 4–19 years from the Viva La Familia Study. Linear and logistic regression and dose-response curves were used to evaluate relations of tCys with obesity, insulin resistance and inflammatory markers including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1) and C-reactive protein (CRP).ResultstCys, methionine and total homocysteine (tHcy) increased with age. Upper tCys quartile was independently associated with a 5-fold increased risk of obesity (95% CI 3.5–8.0, P<0.001), and 2-fold risk of insulin resistance (95% CI: 1.6-5.0, P<0.001; adjusted for body fat%). Within the overweight/obese subgroup, but not in normal-weight children, tCys accounted for 9% of the variability in body fat% (partial r = 0.30, P<0.001; adjusted for age and gender). tCys correlated positively with serum non-esterified fatty acids and leptin, partly independent of body fat, but was not associated with serum IL-6, TNF-α or MCP-1. A positive correlation with CRP disappeared after adjustment for BMI.ConclusiontCys is independently associated with obesity and insulin resistance in Hispanic children and adolescents, highlighting a previously underappreciated link between the sulfur amino acid metabolic pathway and obesity and cardiometabolic risk.

S-Adenosylmethionine Is Associated with Fat Mass and Truncal Adiposity in Older Adults

“…Apart from cystathionine, none showed positive associations (7,9). SAM and SAH have not, to our knowledge, been investigated in the same context.…”

“…Likewise, humans with CBS deficiency are lean with decreased plasma total cysteine (tCys) (6). In contrast, high-plasma tCys is associated with increased BMI and fat mass in children and adults (7)(8)(9). Feeding cystine to mice induces lipogenic enzymes, lowers metabolic rate, and increases visceral adiposity (10).…”

Prospective study of serum cysteine and cysteinylglycine and cancer of the head and neck, esophagus, and stomach in a cohort of male smokers,

“…The subjects of the previous study also had lower BMI (mean 6 SE: 21.8 6 2.6) than in the current study (median: 25.8; IQR: 23.9-28.6). Several studies have shown an association between serum cysteine and obesity and metabolic syndrome (34)(35)(36)(37). Furthermore, the Linxian population consisted mostly of subsistence farmers, whereas members of the ATBC study population had a more-ample and varied diet.…”

Dietary Sulfur-Containing Amino Acids Are Associated with Higher Prevalence of Overweight/Obesity in Northern Chinese Adults, an Internet-Based Cross-Sectional Study

“…Elevation of plasma SAAs is generally associated with an unfavorable lipid profile, and plasma total cysteine is independently associated with body mass index (BMI) [12]. Another study reported that higher plasma total cysteine was associated with an increased risk of obesity and IR in Hispanic children and adolescents [13]. Rodent studies verified that cysteine supplementation increases weight gain despite reduced or consistent food intake [14-16].…”