Growth Hormone Releasing Hormone, or GHRH, is a naturally occurring molecule with similar characteristics and activity in humans and other animals. GHRH is a key potentiator of the GHRH - Growth Hormone (GH) - Insulin like growth factor (IGF-1) axis. Studies in different animal models and humans have shown that GHRH has both direct and indirect functions in development, muscle metabolism, and maintenance of hematological and immune status under physiological and pathological conditions.

The creation of myogenic plasmid vectors that express GHRH has been a significant advancement in the use of GHRH to treat conditions such as cachexia and anemia, to optimize development, and to stimulate immune function. VGX Animal Health has developed species-specific DNA plasmids that can be injected into a skeletal muscle, are not integrated into the cell’s genome, and are expressed by muscle cells for desired periods of time. Plasmid uptake can be enhanced by electroporation. Studies have demonstrated expression for up to two years in large animal models such as cows and pigs. No repeat treatments are necessary within this time period. This innovative method allows GHRH to be naturally produced and maintained by the animal’s own natural physiologic feedback mechanisms.

Pre-clinical animal models:

Plasmid-based GHRH technology has been developed by ADViSYS, Inc., now part of Inovio.

Extensive testing has been conducted for safety and efficacy in several food and companion animal species (cattle, pigs, dogs, cats and horses), as well as laboratory animals (mice and rats).

Long-term hematological and quality of life parameters were improved after a single plasmid GHRH administration in dogs with malignancies or geriatric disabilities.

Preliminary studies on dogs and cats with renal failure showed that the treatment resulted in correction of anemia, while renal function was maintained.

In directly treated cattle, plasmid-mediated GHRH supplementation stimulated T cell and natural killer cell numbers that may be associated with an improvement in immune function, nutritional and health parameters.

The clinical consequences in cattle were a significant reduction in morbidity and mortality as well as improved body condition scores and milk production compared to control animals.

Recent results in rats, pigs and cows have also demonstrated that when pregnant animals are administered plasmid-mediated GHRH supplementation, they give birth to healthier offspring.

Offspring of plasmid-mediated GHRH treated pigs demonstrated a decrease in mortality of 57% compared to offspring from untreated animals.

Morbidity in offspring from treated animals was substantially reduced suggesting the potential for discontinuation of routine antibiotic treatments.

Horses with chronic arthritis/laminitis had significant improvements in body condition, metabolic profiles and resolution of lameness.

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