Study examines effects of growth hormone-releasing hormone on cognitive function

August 6, 2012, JAMA and Archives Journals

Treatment with growth hormone-releasing hormone appears to be associated with favorable cognitive effects among both adults with mild cognitive impairment and healthy older adults, according to a randomized clinical trial published Online First by Archives of Neurology.

"Growth hormone-releasing hormone (GHRH), growth hormone and insulinlike growth factor 1 have potent effects on , their levels decrease with advancing age, and they likely play a role in the pathogenesis of Alzheimer disease," the authors write as background information in the study.

To examine the effects of GHRH on cognitive function in healthy and in adults with (MCI), Laura D. Baker, Ph.D., of the University of Washington School of Medicine and Veterans Affairs Puget Sound Health Care System, Seattle, and colleagues, conducted a randomized, double-blind, placebo-controlled trial in which participants self-administered daily injections of a form of human GHRH (tesamorelin), or placebo.

The authors enrolled 152 adults ranging in age from 55 to 87 years (average age, 68 years) and 137 participants (76 healthy patients and 61 patients with MCI) successfully completed the study. At baseline, at 10 and 20 weeks of treatment, and after a 10-week washout (30 weeks total), the authors collected blood samples and administered parallel versions of .

Among the original 152 patients enrolled in the study, analysis indicated a favorable effect of GHRH on cognition, which was comparable in adults with MCI and healthy older adults. Analysis among the 137 patients who successfully completed the trial also showed that treatment with GHRH had a favorable effect on cognition among both groups of patients. Although the healthy adults outperformed those with MCI overall, the relative to placebo was comparable among both groups.

Treatment with GHRH also increased insulinlike growth factor 1 levels by 117 percent, which remained within the physiological range, and increased fasting insulin levels within the normal range by 35 percent in adults with MCI but not in healthy adults.

"Our results replicate and expand our earlier positive findings, demonstrating that GHRH administration has favorable effects on cognitive function not only in healthy older adults but also in adults at increased risk of cognitive decline and dementia," the authors conclude. "Larger and longer-duration treatment trials are needed to firmly establish the therapeutic potential of GHRH administration to promote brain health in normal aging and 'pathological aging.'"

Explore further: Study evaluates intranasal insulin therapy for adults with mild cognitive impairment or Alzheimer's

More information: Arch Neurol. Published online August 6, 2012. doi:10.1001/archneurol.2012.1970

Related Stories

Study evaluates intranasal insulin therapy for adults with mild cognitive impairment or Alzheimer's

September 12, 2011
Intranasal insulin therapy appears to provide some benefit for cognitive function in patients with amnestic mild cognitive impairment and Alzheimer disease, according to a report published Online First today by Archives of ...

Widespread brain atrophy detected in Parkinson's disease with newly developed structural pattern

December 12, 2011
Atrophy in the hippocampus, the region of the brain known for memory formation and storage, is evident in Parkinson's disease (PD) patients with cognitive impairment, including early decline known as mild cognitive impairment ...

Recommended for you

Even without nudging blood pressure up, high-salt diet hobbles the brain

January 16, 2018
A high-salt diet may spell trouble for the brain—and for mental performance—even if it doesn't push blood pressure into dangerous territory, new research has found.

Brain imaging predicts language learning in deaf children

January 15, 2018
In a new international collaborative study between The Chinese University of Hong Kong and Ann & Robert H. Lurie Children's Hospital of Chicago, researchers created a machine learning algorithm that uses brain scans to predict ...

Preterm babies may suffer setbacks in auditory brain development, speech

January 15, 2018
Preterm babies born early in the third trimester of pregnancy are likely to experience delays in the development of the auditory cortex, a brain region essential to hearing and understanding sound, a new study reveals. Such ...

BOLD view of white matter

January 15, 2018
The brain consists of gray matter, which contains the nerve cell bodies (neurons), and white matter, bundles of long nerve fibers (axons) that until recently were considered passive transmitters of signals between different ...

Does an exploding brain network cause chronic pain?

January 12, 2018
A new study finds that patients with fibromyalgia have brain networks primed for rapid, global responses to minor changes. This abnormal hypersensitivity, called explosive synchronization (ES), can be seen in other network ...

An innovative PET tracer can measure damage from multiple sclerosis in mouse models

January 12, 2018
The loss or damage of myelin, a cellular sheath that surrounds and insulates nerves, is the hallmark of the immune-mediated neurological disorder multiple sclerosis (MS). When segments of this protective membrane are damaged, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.