PLGA microsphere-mediated growth hormone release hormone expression induces intergenerational growth

Area of Science:

• Biotechnology
• Animal Science
• Endocrinology

Background:

• Growth hormone-releasing hormone (GHRH) expression vectors delivered via muscle injection can improve animal growth.
• Biodegradable microspheres, such as polylactic-co-glycolic acid (PLGA), are used for sustained GHRH delivery.
• Intergenerational effects of GHRH delivery systems are not well understood.

Purpose of the Study:

• To investigate the intergenerational effects of PLGA-encapsulated plasmid-mediated GHRH supplements.
• To assess the impact of GHRH delivery on offspring growth and GHRH expression.

Main Methods:

• pCMV-Rep-GHRH microspheres were injected into pregnant mice.
• Offspring growth and GHRH expression were measured using RT-PCR and immunohistochemistry.
• Growth hormone (GH)-positive cells and insulin-like growth factor-I (IGF-I) serum levels were analyzed.

Main Results:

• GHRH expression was detected in offspring 3-21 days post-injection.
• GHRH-treated offspring showed a 48.2% increase in GH-positive cells compared to controls.
• Offspring treated with GHRH were 6.15% larger and had significantly higher IGF-I serum levels.

Conclusions:

• Intramuscular GHRH expression mediated by PLGA microspheres significantly enhances intergenerational growth.
• PLGA microspheres provide an effective sustained release system for GHRH delivery.
• This delivery method holds potential for improving animal growth across generations.