(HealthDay News) – There seems to be no evidence to support human-to-human transmission of Alzheimer’s disease (AD) or Parkinson’s disease (PD) via transmission of neurodegenerative disease (ND)-associated proteins (NDAPs) in recipients of cadaveric human growth hormone (c-hGH), according to a study published online Feb. 4 in JAMA Neurology.
Noting the growing evidence of cell-to-cell transmission of NDAPs, David J. Irwin, MD, from the University of Pennsylvania Perelman School of Medicine in Philadelphia, and colleagues examined evidence for human-to-human transmission of AD, PD, and related NDAPs in 34 routine autopsy subjects (10 non-ND controls and 24 patients with ND) and among recipients of c-hGH in the U.S. National Hormone and Pituitary Program (NHPP) cohort.
In ND and control patients, the researchers identified mild amounts of pathological tau, amyloid-β, and α-synuclein deposits in the adeno/neurohypophysis. Among U.S. NHPP c-hGH recipients, there were no cases of AD or PD; three deaths were attributed to amyotrophic lateral sclerosis.
“In this unique in vivo model of human-to-human transmission, we found no evidence to support concerns that NDAPs underlying AD and PD transmit disease in humans despite evidence of their cell-to-cell transmission in model systems of these disorders,” the authors write. “Further monitoring is required to confirm these conclusions.”
Two authors disclosed financial ties to the pharmaceutical industry.