‘Un-growth hormone’ increases longevity

Bywww.kurzweilai.net

A compound that acts in the opposite way to growth hormone can reverse some of the signs of aging, a research team that includes a Saint Louis University physician has shown. The finding may be counter-intuitive to some older adults who take growth hormone, thinking it will help revitalize them.

“Many older people have been taking growth hormone to rejuvenate themselves,” Morley said. “These results strongly suggest that growth hormone, when given to middle aged and older people, may be hazardous.”

The scientists studied the compound MZ-5-156, a “growth hormone-releasing hormone (GHRH) antagonist.” They conducted their research in the SAMP8 mouse model, a strain engineered for studies of the aging process. They found that MZ-5-156 had positive effects on oxidative stress in the brain, improving cognition, telomerase activity (the actions of an enzyme which protects DNA material) and life span, while decreasing tumor activity.

MZ-5-156, like many GHRH antagonists, inhibited several human cancers, including prostate, breast, brain and lung cancers. It also had positive effects on learning, and is linked to improvements in short-term memory. The antioxidant actions led to less oxidative stress, reversing cognitive impairment ^[2] in the aging mouse.