Growth Hormone Shows Potential as Alternative to Opioid Use for Pain Relief

Published Feb. 15, 2017
Pain

Impactful science can take its roots from just about anywhere, including, in this case, an informal chat between a pain management physician and a PhD researcher.

John Rose, MD, co-director of the Inpatient Pain Rehabilitation Program, was describing his anecdotal experience in utilizing growth hormone to treat a patient’s pain.

Researcher Michael Jankowski, of the Department of Anesthesia, was intrigued. “It sparked my interest in how a pituitary hormone may control pain in children,” he recalls.

That curiosity led to a study, in which Jankowski was senior author, that concluded that growth hormone can block inflammation-induced nociceptor sensitization during postnatal development.

This leads to reduced behaviors that mimic pain, possibly by suppressing the upregulation of an insulin-like growth factor 1 receptor called IGFr1 within dorsal root ganglia.

It was known that, in the dorsal root ganglia, cutaneous inflammation alters the function of primary afferents and gene expression, but the exact mechanisms of injury-induced sensitization and behavioral hypersensitivity were not fully understood. Neither was the way growth hormone in neonates appeared to affect nociception, the nervous system's normal response to harmful stimuli.

Future studies to understand more about how this process works could eventually lead to improved pain medications for children.

“The possibility of finding a new way to treat pain in children without the use of standard agents like opioids is incredibly exciting,” Jankowski says. “It is a driving force behind our work. The results of this study only solidify our aspirations to achieve this goal.”

Cutaneous growth hormone (GH) levels are reduced one day after inflammation of the skin in neonatal mice (A). This can be blocked by supplementing inflamed mice with GH. Charts B and C depict results of mechanical and thermal stimulation after mice were injected with P14 carrageenan to induce skin hypersensitivity. In mice treated with GH (light blue bars), peripheral hypersensitivity induced by inflammation is blocked. (*) indicates significant differences compared to naïve or baseline. (*) indicates differences compared to baseline but not time matched GH treated groups.

Click image to enlarge.

Citation

Liu X, Green KJ, Ford ZK, Queme LF, Lu P, Ross JL, Lee FB, Shank AT, Hudgins RC, Jankowski MP. Growth hormone regulates the sensitization of developing peripheral nociceptors during cutaneous inflammation. Pain. 2017 Feb;158(2):333-346.