Introduction:
Recent years have shown a growing interest in the role of human growth hormones in mammalian aging. According to recent research, GH may impact the maintenance of genetic material (DNA), but its effects in cancer cells differ from those in normal cells. This implies that GH might have a role in the development of cancer as well as aging. Additionally, studies have examined GH's role in DNA methylation, which may be a mechanism by which GH affects the aging process. Several studies have been performed to investigate how GH impacts various types of fat tissues. According to recent studies, scientists now have a better understanding of the trade-offs associated with aging and lifespan, as well as how HGH affects these processes.
Evidence suggests that, although there are significant species variations, most of the aging-related GH effects found in laboratory mice also apply to other mammals, including humans. It is hypothesized that significant variations in life history, energy partitioning, and reproductive strategy between species with differing paces of life account for the disparities in the effects of GH on lifespan in mice versus humans. Humans live leisurely lives, which contributes to longevity and makes it difficult to achieve further increases in lifespan. Other factors contributing to this trend include social organization, public health initiatives, and medical advancements.
What Are Growth Hormones?
Growth hormone supports the growth of children and aids in the maintenance of tissues and organs throughout life. The pituitary gland, a little gland at the base of the brain, is the source of it. However, the pituitary gland gradually lowers its growth hormone production in mid-life. The use of synthetic Human Growth Hormone (HGH) to prevent some of the effects of aging, such as decreasing muscle and bone mass, has become more popular due to this natural slowdown.
Who Needs HGH Treatment?
Adults who are deficient in growth hormones, apart from experiencing the typical aging-related decline in growth hormone, may receive synthetic HGH injections from a physician. Benign tumors most commonly cause growth hormone deficiency on the pituitary gland (pituitary adenoma) and by radiation or surgery for adenomas. Those who are deficient in growth hormone may benefit from HGH injections in the following ways:
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Boost their ability to work out.
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Boost the density of bones.
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Boost the muscle mass.
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Reduce body fat.
HGH therapy is also appropriate for adults with growth hormone deficits linked to HIV/AIDS that cause an unequal distribution of body fat.
What Are the Side Effects of HGH Treatment?
For healthy people, using HGH may have a variety of adverse effects, such as:
- Carpal tunnel syndrome.
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Heightened resistance to insulin.
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Diabetes type 2.
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Edema, or arm and leg swelling.
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Pain in the muscles and joints.
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Gynecomastia, or the growth of breast tissue in men.
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Elevated risk of specific types of cancer.
Because of the small number and short duration of clinical trials conducted on healthy older individuals, very little is known about the long-term effects of HGH administration.
Does Growth Hormone Reverse Aging?
A 1990 study by Rudman et al. found that GH medication could reverse some symptoms of aging, such as an increase in body fat and a loss in muscle mass. This sparked a wave of interest in the possible advantages of growth hormone therapy and led to a vigorous push for GH as an anti-aging treatment, along with nutritional supplements meant to increase endogenous GH secretion. The idea that GH is an "elixir of youth" was debunked mainly by later research, which demonstrated that treating adults without a proven GH deficiency with GH has no discernible benefits other than a slight improvement in body composition and that these benefits are outweighed by negative side effects.
What Is the Effect of Growth Hormone on DNA Damage and Repair?
Aging and cancer development are linked to DNA damage, including single- and double-strain breaks and the accumulation of somatic mutations. Preventing premature aging requires maintaining the genome and repairing DNA damage. Both GH and IGF-I are involved in these processes. The onset and course of neoplastic disease have been associated with the actions of both GH and IGF-I. Furthermore, a strong body of epidemiological research links height, which is a GH and IGF-I-dependent trait, to several cancer types in both men and women. Pituitary-derived (endocrine) GH and autocrine GH are produced by tumors, such as GH secreted by senescent cells within the tumor tissue, which impact the malignant cells.
GH has been demonstrated to cause DNA damage in normal (non-transformed) cells and tissues, increase sensitivity to agents that damage DNA, and decrease DNA repair, in contrast to its effects on DNA damage and repair in malignancies. Oxidative stress, modified phosphorylation of ataxia-telangiectasia-mutated kinase and p53 protein, and alterations in the expression of genes linked to stress response or repair pathways are some of the mechanisms behind these effects. The longer lifespans and health spans of GH-deficient and GH-resistant mice, as well as the exceptional defense against cancer of GH-resistant people, are due in part to lower levels of DNA damage and improved DNA repair capabilities.
What Is the Role of Body Weight in Aging?
Several studies have revealed that increased body weight in adults is associated with an accelerated rate of aging. Analysis of DNA methylation provides an accurate epigenetic clock of aging. This attribute can be used as a novel aging biomarker and also helps estimate the biological age instead of the chronological age. A study on mice with different body weights revealed an acceleration in biological age in mice with increased body weight, and increased body weight is associated with an increase in the growth hormone, thus establishing the link.
What Is the Impact of Growth Hormone on Adipose Tissue?
Growth hormones impact the function and amount of white and brown adipose tissue. Studies in mice with genetic growth hormone deficiency showed increased thermogenic activity and utilization of the subcutaneous fat for energy, thus resulting in healthy aging and an extension of longevity.
Conclusion
Major, consistent, and well-documented effects of GH activity on laboratory mice's lifespan have been found; some of the conclusions drawn from these animal experiments are applicable to other mammalian species, including humans. Nonetheless, there are many contradictions and disagreements. The most notable is the discrepancy between human and mouse longevity research results. On the other hand, in both species, pathological GH excess is linked to comorbidities and shorter lifespans.
