Levels of a male hormone produced by the adrenal glands could provide useful information on the severity of spinal and bulbar muscular atrophy, or SBMA, a study reports.
The identified the hormone as DHEA sulfate.
Researchers’ study, published in the Journal of Neurology, is titled “The metabolic and endocrine characteristics in spinal and bulbar muscular atrophy.”
SBMA, also known as Kennedy’s disease, is a genetic disorder that leads to progressive muscle weakness and atrophy. It is characterized by an expansion of a CAG repeat in the DNA sequence of the androgen receptor gene.
A number of researchers have thought that lowering testosterone and insulin levels could be a way to treat SBMA, but the approach failed in clinical trials. The studies highlighted the need for markers that could predict the disease’s outcome.
German researchers studied 28 potential metabolism and hormone biomarkers of SBMA in 80 patients. The University of Ulm-led team recruited patients through neuromuscular referral centers.
Ninety-nine percent of the patients had muscle weakness, 77% had difficulty swallowing, 76% had tremors, and 75% of the men had breast tissue growth, or gynecomastia. Other symptoms included muscle cramps and pain, difficulty speaking, sensation problems, and breathing difficulties.
Analysis of patients’ fat levels showed that 78% had total cholesterol levels that were too high, 56% had higher than normal levels of triglycerides, and 66% had too much LDL or bad cholesterol. Several patients displayed glucose metabolism problems. Forty-four percent were insulin resistant, and others had elevated levels of liver enzymes.
The most consistent biomarker was creatinine enzyme, which is associated with muscle damage. Ninety-four percent of patients had higher than normal levels of it in their blood.
Researchers found no biomarkers that could predict muscle weakness or the disease’s duration, however.
Creatinine enzyme, “a well-established indicator of muscle integrity, was by far the most consistently elevated disease marker, potentially indicating skeletal muscle involvement,” the researchers wrote. The finding supported previous studies suggesting that scientists could develop a treatment for SBMA that revolved around the enzyme.
Of the 28 potential biomarkers that the team studied, only DHEA sulfate — a weak male hormone produced by the adrenal glands — had a significant correlation with CAG repeat length and partial muscle paralysis.
They said DHEA could develop into a biomarker of the disease’s severity.