Tesamorelin vs. naturalna produkcja hormonu wzrostu: jakie zmiany zachodzą w organizmie?

Tesamorelin is a synthetic analogue of the GHRH peptide, specifically designed to enhance the body’s natural growth hormone production, rather than directly replacing GH with external hormone injections [1,2]. Structurally, tesamorelin is a stabilised 44-amino acid version of human GHRH and incorporates a trans-3-hexenoic acid fatty acid modification, which improves stability and allows the peptide to remain active in the body for a longer duration [1,2]. Once administered subcutaneously, tesamorelin binds to GHRH receptors located on somatotroph cells within the pituitary gland. This interaction stimulates the pulsatile release of endogenous, or naturally produced, growth hormone, which subsequently increases circulating IGF-1 levels [1–5].

One of the most significant differences between tesamorelin and direct recombinant human growth hormone (HGH) therapy is how each method affects the body's hormonal regulation system. Natural GH production occurs in pulses throughout the day and night, and is controlled by hypothalamic signalling and feedback from hormones such as IGF-1. Tesamorelin works by enhancing this existing physiological pathway, helping the body release larger amounts of its own GH while preserving much of the natural regulatory mechanisms [3–5]. In contrast, direct HGH injections bypass the pituitary gland entirely, delivering exogenous growth hormone directly into circulation, which can alter normal hormonal signalling patterns.

Clinical studies show that the increase in GH and IGF-1 induced by tesamorelin leads to measurable changes in body composition and metabolism. In a placebo-controlled study conducted by Falutz J et al. (2005), tesamorelin increased IGF-1 levels by approximately 48% at a dose of 1 mg and by 65% at a dose of 2 mg daily over a 12-week period in HIV-positive individuals with abdominal fat accumulation [4]. These hormonal changes were associated with a significant reduction in visceral adipose tissue, i.e. deep abdominal fat, improved triglyceride levels, preservation of subcutaneous fat, and an increase in lean body mass without a significant deterioration in glucose control.

Further clinical trials yielded similar results. Falutz J et al. (2007) demonstrated that tesamorelin reduced visceral abdominal fat by approximately 15%, whilst improving the lipid profile in patients with HIV-associated lipodystrophy [5]. Long-term phase III data presented by Falutz J et al. (2010) confirmed that elevated IGF-1 levels and reductions in visceral fat and waist circumference could be maintained for up to 52 weeks during continued treatment [6].

Studies also suggest that tesamorelin may influence liver metabolism and cellular energy production by activating the GH–IGF-1 pathway. In randomised clinical trials involving individuals with HIV-associated non-alcoholic fatty liver disease (NAFLD), tesamorelin significantly reduced liver fat content whilst improving the expression of metabolic and mitochondrial genes [7,8]. Fourman LT et al. (2020) observed increased expression of genes associated with oxidative phosphorylation and mitochondrial metabolism, as well as inhibition of pathways linked to liver inflammation and fibrosis [7]. Mitochondria are the structures responsible for energy production in cells; therefore, these results suggest a possible improvement in the way cells produce and utilise energy.

Further research indicates that the increase in GH and IGF-1 associated with tesamorelin may also affect muscle quality and cognitive function. Adrian S et al. (2019) noted improvements in muscle density and area in HIV-positive adults treated with tesamorelin [9]. Furthermore, Baker LD et al. (2012) demonstrated improvements in executive function and memory in older individuals with a concurrent physiological increase in IGF-1 levels [10]. Executive functions refer to the mental processes involved in concentration, decision-making, planning, and problem-solving.

Generally speaking, natural growth hormone is produced by the pituitary gland under the control of endogenous GHRH signalling, whereas tesamorelin is a synthetic GHRH peptide designed to augment this natural pathway. By stimulating the body's own production of GH and IGF-1 in a more physiological manner, tesamorelin has been associated with reductions in visceral and hepatic fat, improved metabolic function, increased lean body mass, and potential support for muscle quality and cognitive function [4–10]. Tesamorelin obtainable for laboratory research is available from suppliers such as SemaxPolska. Please note that findings from research pertain to controlled scientific conditions and do not confirm clinical efficacy in other applications.

Disclaimer

The content is for educational and scientific information purposes only and should not be interpreted as medical advice, diagnosis, or therapeutic recommendation. Tesamorelin is a prescription medication approved primarily for the treatment of HIV-associated lipodystrophy. Therapies affecting growth hormone and IGF-1 pathways require appropriate medical supervision, laboratory monitoring, and individual assessment by a qualified healthcare professional.