Human Growth Hormone (HGH) is released by the somatotropic cells of the anterior pituitary gland. Its production is stimulated by growth hormone -releasing hormone released by the hypothalamus. It plays an important role growth and development of cells and tissues in humans. In addition, it is has an essential role in protein synthesis, lipolysis, glucose homeostasis and bone mineralisation.
HGH supplements are sometimes used by athletes to enhance performance, but it has been banned by a number of sporting authorities.
In clinical practice however, HGH production can be reduced due to hypopituitarism or pituitary tumors (adenoma), and such patients require replacement therapy. Growth Hormone deficiency in adults can result in the following:
Reduced bone mineral density
Reduced exercise capacity
Emotional lability and psychological distress
Following adequate clinical assessment and investigation, an appropriate treatment regime is prescribed, which includes HGH supplement therapy with recombinant Human Growth Hormone.
Human Growth Hormone can help control obesity.
Recombinant Human Growth Hormone (rhGH)
Recombinant HGH is now widely used in treatment of patients with growth hormone deficiency. However, its uses are not just limited to that and have been listed below:
1. Adult Growth Hormone deficiency syndrome
Studies have shown that replacement therapy with rhGH in patients with HGH deficiency have shown a significant improvement in lipid profile and psychological well being.
Over time, there appears to be an improvement in muscle strength, and certainly a recent study showed that this improvement persists during a 10 year follow up period. In particular, Gibney et al showed a marked increase in lean body mass though there was no significant effect on muscle strength. 1
A favourable reduction in low density lipoprotein (LDL) cholesterol was also noted, thus reducing the risk of future cardiovascular disease. The patient’s mood was also considerably better, with a significant increase in energy levels noted. In short, the effect of rhGH therapy is extremely favourable and is associated with a good outcome during a 10 year follow up period.
2. Reduced HGH in elderly
Trials in elderly patients who suffer from physiological decreases in growth hormone has shown variable results. While some studies have shown an increase in lean muscle mass2, other studies have shown reduced muscle strength.3 Unfortunately, current evidence does not support the use of rhGH in elderly patients. 4 In particular, rhGH was portrayed as an anti-ageing agent, but yet again this is unsupported by evidence.
3. Dilated Cardiomyopathy
rhGH has been noted to improve left ventricular function and symptoms associated with congestive cardiac failure over short treatment durations.5 However, this effect does not appear to be consistent over longer treatment periods, and can in fact be detrimental.
4. HIV associated cachexia
Recent studies have shown that a 12 week treatment of patients with HIV with rhGH increases lean body mass and reduces body fat. 6 However, this effect is seen at high treatment doses, and long term treatment effects are yet to be investigated.
5. Enhance athletic performance
rhGH has been notoriously used by performance athletes to improve their athletic capabilities. However, most administrative bodies have banned the use of rhGH in national and international events.
These are just a few common uses of rhGH. There are a number of studies still being conducted to assess its effects in both adults and children, and the prospects appear exciting.
1. J. Gibney, J. D. Wallace, T. Spinks, L. Schnorr, A. Ranicar, R. C. Cuneo, S. Lockhart, K. G. Burnand, F. Salomon, P. H. Sonksen, and D. Russell-Jones The Effects of 10 Years of Recombinant Human Growth Hormone (GH) in Adult GH-Deficient Patients JCEM 1999 84: 2596-2602
2. Welle S, Thornton C, Statt M, et al. Growth hormone increases muscle mass and strength but does not rejuvenate myofibrillar protein synthesis in healthy subjects over 60 years old. JCEM. 1996; 81:3239–3243
3. Taaffe DR, Pruitt L, Reim J, et al. Effect of recombinant human growth hormone on the muscle strength response to resistance exercise in elderly men. JCEM. 1994;79:1361–1366
4. Robert Marcus, Gail Butterfield, Leah Holloway, Linda Gilliland, David J Baylink, Raymon L Hintz, and Barry M Sherman Effects of Short Term Administration of Recombinant Human Growth Hormone to Elderly People JCEM 1990 70: 519-527
5. Fazio S, Sabatini D, Capaldo B, et al.Apreliminary study of growth hormone in the treatment of dilated cardiomyopathy. NEJM.1996; 334:809–814
6. Mulligan K, Grunfeld C, Hellerstein MK, et al. Anabolic effects of rh growth hormone in patients with wasting associated with HIV infection. JCEM. 1993; 77:956 –962