Effects of administration of two growth hormone-releasing hormone plasmids to gilts on sow and litter performance for the subsequent three gestations.

Objective: To determine whether a novel optimized plasmid carrying the porcine growth hormone-releasing hormone (GHRH) wild-type cDNA administered at a lower dose was as effective at eliciting physiologic responses as a commercial GHRH plasmid approved for use in Australia.

Animals: 134 gilts.

Procedures: Estrus was synchronized and gilts were bred.

Gene therapy by electroporation for the treatment of chronic renal failure in companion animals.

Background: Growth hormone-releasing hormone (GHRH) plasmid-based therapy for the treatment of chronic renal failure and its complications was examined. Companion dogs (13.1+/-0.

Growth hormone-releasing hormone plasmid treatment by electroporation decreases offspring mortality over three pregnancies.

LifeTideSW5 is a growth hormone-releasing hormone (GHRH)-expressing plasmid delivered by intramuscular (IM) electroporation (EP), and the first therapeutic plasmid delivered by this physical method to be approved for use in food animals. Gestating sows (n = 997) were treated once with a single 5-mg GHRH-plasmid by EP or served as controls. Data on offspring from three parities subsequent to treatment were collected.

Parameters for DNA vaccination using adaptive constant-current electroporation in mouse and pig models.

Enhancing the expression of DNA vaccines requires that specific conditions of delivery are optimized. We describe experiments using adaptive constant-current electroporation (EP) in mice and pigs examining parameters such as target muscle, delay between plasmid delivery and onset of EP pulses and DNA vaccine formulation; our studies show that concentrated formulations result in better expression and immunogenicity. Furthermore, various conditions of EP that limit the amount of muscle damage were measured.

Double-blinded, Placebo-controlled plasmid GHRH trial for cancer-associated anemia in dogs.

The use of growth hormone releasing hormone (GHRH) plasmid-based therapy to treat companion dogs with spontaneous malignancies and anemia receiving a cancer-specific treatment was examined in a double-blinded, placebo-controlled trial. The dogs (age 10.5 +/- 2.

Plasmid-based expression technology using growth hormone releasing hormone: a novel method for physiologically stimulating long-term growth hormone secretion.

Novel DNA-based technologies were recently introduced for various purposes, such as screening of targets identified from genomic projects, shuffled molecules for vaccination, or to direct the in vivo production of hormones and other peptides for therapeutic or preventative applications. We have used a plasmid-based technology to deliver growth hormone releasing hormone (GHRH) to various animal species for screening, toxicology and therapy. A single intramuscular injection of a low dose of plasmid followed by electroporation can ensure that the target species will produce physiological levels of GHRH for extended periods of time, which would replace costly, frequent injections of the recombinant hormone and improve the quality of life and compliance of patients.

Highly efficient constant-current electroporation increases in vivo plasmid expression.

Electroporation has been demonstrated as an effective technique for enhancing the delivery of plasmids coding for DNA vaccines and therapeutic proteins into skeletal muscle. Nevertheless, constant-voltage techniques do not take into account the resistance of the tissue and result in tissue damage, inflammation, and loss of plasmid expression. In the present study, we have used a software-driven constant-current electroporator to deliver plasmids to mice and small and large pigs.

Growth hormone releasing hormone plasmid supplementation, a potential treatment for cancer cachexia, does not increase tumor growth in nude mice.

Growth hormone releasing hormone (GHRH) is known to have multiple anabolic effects and immune-stimulatory effects. Previous studies suggest that treatment with anabolic hormones also has the potential to mitigate the deleterious effects of cancer cachexia in animals. We studied the effects of plasmid-mediated GHRH supplementation on tumor growth and the role of antitumor immune cells with two different human tumor cell lines, NCI-H358 human bronchioalveolar carcinoma and MDA-MB-468 human breast adenocarcinoma, subcutaneously implanted in nude mice.

Optimization of electroporation parameters for the intramuscular delivery of plasmids in pigs.

Increased transgene expression after plasmid transfer to the skeletal muscle is obtained with electroporation in many species, but optimum conditions are not well defined. Using a plasmid with a muscle-specific secreted embryonic alkaline phosphatase (SEAP) gene, we have optimized the electroporation conditions in a large mammal (pig). Parameters tested included electric field intensity, number of pulses, lag time between plasmid injection and electroporation, and plasmid delivery volume.

Effects of plasmid-mediated growth hormone-releasing hormone supplementation on LL-2 adenocarcinoma in mice.

This study was designed to measure the effects of plasmid growth hormone-releasing hormone (GHRH) supplementation on LL-2 (Lewis lung adenocarcinoma) tumor-bearing immunocompetent mice. Male and female mice (n = 20/group/experiment) received 2.5 x 10(6) LL-2 cells in the left flank.

Maternal GHRH plasmid administration changes pituitary cell lineage and improves progeny growth of pigs.

Previous studies from our laboratory have demonstrated that administration of a myogenic plasmid that encodes a protease-resistant growth hormone-releasing hormone (HV-GHRH) to pregnant rat dams augmented long-term growth in first-generation progeny. In the present study, gilts were injected intra-muscularly at day 85 of gestation with 0, 0.1, 0.