Rochester, Minnesota - A Mayo Clinic-led study found that obese teenagers have lower levels of a hormone potentially tied to weight management than teens of normal weights. The study is published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism.

“Our study is the first to look at levels of spexin in the pediatric population,” says Seema Kumar, M.D., Mayo Clinic Children’s Center, one of the study’s authors. “Previous research has found reduced levels of this hormone in adults with obesity. Overall, our findings suggest spexin may play a role in weight gain, beginning at an early age.”

For children and teens, the Centers for Disease Control and Prevention defines obesity as having a body mass index (BMI) at or above the 95th percentile for children and teens of the same age and sex.

Obesity affects about 17 percent of U.S. children, according to the Endocrine Society’s “Endocrine Facts and Figures Report.” Childhood obesity is associated with an estimated $14.1 billion in additional prescription drug, emergency department visit and outpatient visit costs each year.

The cross-sectional study analyzed spexin levels in 51 obese and 18 teenagers of normal weights between ages 12 and 18. The participants had blood samples taken between 2008 and 2010 as part of separate clinical trials. Researchers tested the blood samples to measure spexin levels.

Researchers divided the teenagers into four groups based on their spexin levels. Among the participants with the lowest levels of spexin, the odds of having obesity were 5¼ times higher than in the group with the highest levels of the hormone. Unlike what has been noted in adults, there was no association between spexin levels and fasting glucose.

“It is noteworthy that we see such clear differences in spexin levels between obese and normal weight adolescents,” Kumar says. “Since this is a cross-sectional study, more research is needed to explore the physiological significance of spexin, how it may be involved in the development of childhood obesity, and whether it can be used to treat or manage the condition.”

Other authors of the study are:

  • Jobayer Hossain, Ph.D., Nemours Biomedical Research
  • Nicole Nader, M.D., Park Nicollet Health Services
  • Roxana Aguirre Castaneda, M.D., University of Illinois College of Medicine
  • Swetha Sriram, M.D., Mayo Clinic
  • Babu Balagopal, Ph.D., Nemours Children’s Specialty Care and Mayo Clinic

This research was supported by Mayo Clinic Center for Translational Science Activities (CTSA)  Grant No. UL1 TR000135 from the National Center for Advancing Translational Sciences, a component of the National Institutes of Health (NIH).