Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023380 (lethargy)
 5,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent research clearly shows that fusion genes can be microinjected into a pronucleus of an ovum and integrate into the pig genome. Animals with such fusion genes are called 'transgenic'. The percentage of injected ova that developed into transgenic pigs varied among experiments from 0.31% to 1.73%. The percentage of transgenic pigs that expressed the fusion gene ranged from 17% to 100%. Eleven different regulatory sequences have been used for fusion genes transferred into pigs. Some of these regulatory sequences directed strong gene expression, but control over level of expression was inadequate. Other regulatory sequences directed weak expression, but imparted only brief spikes of induced expression. The predominant gene coding sequences transferred were for growth-related hormones. Elevation of growth hormone (GH) in expressing transgenic pigs enhanced plasma concentrations of insulin-like growth factor-I (IGF-I), insulin, and glucose, improved feed efficiency about 15%, and markedly reduced subcutaneous fat compared to nontransgenic siblings. Growth rate was enhanced in some transgenic GH pigs but not in others, possibly due to dietary limits. The 'over-expression' of GH was detrimental to the general health of most transgenic pigs. The most prevalent problems were lethargy, lameness, and gastric ulcers. Gilts that expressed foreign GH genes were anoestrous. Boars that expressed foreign GH genes lacked libido, but their semen was fertile when used by artificial insemination. Six different fusion genes have been transmitted from transgenic founders to progeny. Most of the transgenic pigs that produced progeny transmitted the fusion gene as an autosomal dominant trait to about half of their progeny. Regulatory sequences that will permit full control of gene expression must be developed before the full potential of gene transfer in pigs can be realized.
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PMID:Expression and performance in transgenic pigs. 219 41

We have produced transgenic pigs that harbour structural genes for bovine and human growth hormone (bGH and hGH) ligated to a mouse metallothionein-I (MT) promoter, human growth hormone-releasing factor (hGRF) ligated to the MT or mouse albumin (ALB) promoter, and human insulin-like growth factor-I (hIGF-I) ligated to MT promoter. From 0.31 to 1.03% of microinjected ova developed into transgenic pigs with the various fusion genes. Foreign GH was present in plasma of 61% of the MT-hGH and 89% of the MT-bGH transgenic pigs. Two of 7 pigs with MT-hGRF and all 3 ALB-hGRF transgenic pigs had high concentrations of GRF in their plasma, but plasma concentrations of porcine GH (pGH) were not higher in GRF transgenic pigs than in littermate control pigs. In contrast, plasma concentrations at birth ranged from 3 to 949 ng hGH/ml for MT-hGH transgenic pigs and 5 to 944 ng bGH/ml for MT-bGH transgenic pigs. Presence of the foreign GH depressed endogenous pGH to non-detectable levels. In MT-bGH transgenic pigs, plasma IGF-I was elevated more than 2-fold, plasma glucose was elevated about 30 mg/dl, and plasma insulin was 20-fold higher than in littermate or sibling control pigs. Two lines of pigs expressing the MT-bGH transgene gained 11.1% and 13.7% faster, and were 18% more efficient in converting feed to body weight gain than were sibling control pigs. Expression of the MT-bGH transgene caused a marked repartitioning of nutrients from subcutaneous fat into other carcass components, including muscle, skin, bone and certain organs. The persistent excess hGH or bGH in transgenic pigs was detrimental to general health; lameness, lethargy and gastric ulcers were the most prevalent problems. Gilts that expressed the hGH or bGH transgenes were anoestrous. Germ-line transmission was obtained in 4 of 5 expressing transgenic boars and 4 of 5 nonexpressing transgenic boars and gilts. From 2% to 73% of progeny inherited a transgene from founder transgenics. All transgenic progeny of MT-hGH, MT-bGH and MT-hGRF founder males expressed the transgene if their sire also expressed the gene. The concentration of bGH or hGH in plasma of transgenic progeny was similar to the concentration present in the founder transgenic.
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PMID:Integration, expression and germ-line transmission of growth-related genes in pigs. 221 18

The purpose of this study was to determine the effects of recombinant human GH (rhGH; 0.025 mg/kg.day) and one of two doses of recombinant human insulin-like growth factor-I (rhIGF-I; 0.015 and 0.060 mg/kg, twice daily) on body composition in elderly women. Sixteen healthy elderly women (mean age +/- SEM, 71.9 +/- 1.3 yr) were randomly assigned to receive either rhGH (GH; n = 5), low dose rhIGF-I (n = 6), or high dose rhIGF-I (n = 5). A 2-week predrug baseline period was followed by 4 weeks of hormone treatment, with a standardized diet fed throughout. All groups experienced a significant increase in serum IGF-I and IGFBP-3 levels over the treatment period, accompanied by significant decreases in IGF-II (P < 0.05). Fat mass decreased in all groups, with significant increases in lean body mass and nitrogen retention occurring in the high dose IGF and GH groups. Total body water did not change, whereas increases observed in intracellular fluid approached significance (P = 0.06). These anabolic changes were accompanied by numerous negative side-effects in the GH and high dose IGF groups, including headaches, lethargy, joint swelling/pain, and bloatedness. The low IGF dose was well tolerated. These results demonstrate that the administration of rhGH and rhIGF-I for 4 weeks results in anabolic changes in body composition in elderly women.
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PMID:The effects of recombinant human insulin-like growth factor-I and growth hormone on body composition in elderly women. 753 17