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Growth factors (GF) are small protein chains, commonly known as polypeptides that bind to cell surface receptor sites and exert actions directly on the target cells. This is generally done through cellular proliferation and or differentiation.
Some GFs exert a generalized effect, while others are cell and action specific. There are many different classes of GFs. Some common ones are: Insulin-like Growth Factor (IGF-1) which is responsible for much of the Growth Hormone (GH) action in the body, Interleukins (IL), Fibroblast Growth Factors (FGF), Transforming Growth Factor (TGF), Tumor Necrosis Factor (TNF), Epidermal Growth Factor (EGF), Transforming Growth Factors-b (TGFs-b), and erythropoietin (EPO).
GFs come from a wide variety of sources. Epithelial Growth Factors (EGF) comes from sub maxillary gland, erythropoietin comes from the kidney, and FGF comes from a wide range of cells. A unique family of growth factors that are secreted primarily by leukocytes (white blood cells) are called cytokines. When such cytokines are secreted by lymphocytes, they are called lymphokines. Many of the lymphokines are also known as interleukins (ILs). Not only are interleukins secreted by leukocytes, but they also retain the ability to affect the cellular responses of leukocytes.
Different GFs have different jobs to do. Generally, all of them work at the cellular level to:
While hormones are generally more specific and sometimes work through other mediations elicited from their simulation of intermediate organs, GFs often act directly on the target tissue and have a wide range of effects. Its action is mostly stimulatory. It can also work synergistically with other GFs or hormones to elicit a biological effect. Growth hormones, for example, exert their effects in the body via Insulin-like Growth Factor (IGF-1). In other words, it is the IGF-1 that actually carries out the function of the growth hormone and not growth hormone itself.
FGF is a group of GFs that act on the fibroblast within the body. Fibroblast are basic building blocks of fibrous tissue, including the brain, nervous system, eye, blood vessels, heart, stomach, skin, liver, kidney, muscle and bone. In fact, most cells within these organs possess receptors for FGF and therefore are susceptible to its biological effect.
There are at least 19 distinct members of the FGF family, which interact with at least 4 distinct types of cell-surface receptors. It is evident that the amount of FGF is essential for optimum body function, and disruption of FGF can lead to disease states, including achondroplasia and craniosynotosis syndromes.
FGF can be bound to inert, non-toxic polymers to form a conjugated molecule. This is usually done through a series of chemical reactions. Substances commonly used as polymers include polysaccharides or muco-adhesives.
FGF is a small protein that can be easily denatured when exposed to heat or acid. Ingesting FGF, for example, will expose FGF to gastric acid, which will quickly denature it. When the FGF is conjugated, the protein is more stable and protected from the digestive enzymes, for example. Conjugation can further program the FGF's release from its carrier in order to ensure that the desired action of the GF, on a specific site, is maintained.
The natural progression of the aging process is due to cellular degeneration. Oxidative stress and free radical pathology has been well studied, in this respect, as a causative factor. FGF helps maintain the target organs that contain fibrous tissue; including the eyes, heart, brain, skin, and the musculoskeletal system. It helps repair damaged tissue. For example, FGF can help restore normalcy in injured nerve tissue or damaged blood vessels in order to prevent further clotting or stokes. In the case of a duodenal ulcer, it can reduce healing time. The fortification and re-growth of the epidermis and its underlying circulation will lead to healthier skin and fewer wrinkles.
Non-damaged aging cells can also benefit from FGFs. Laboratory studies, for example, have shown that cells that are unable to replace themselves (such as eye tissue), can be stimulated to renew cell layers. An example of this is the pigmented layer in the eye.
Body parts that respond to biological stimulation of FGF include:
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About The Author
Michael Lam, M.D., M.P.H., A.B.A.A.M., is a western trained physician specializing in nutritional and anti-aging medicine. Dr. Lam received his Bachelor of Science degree from Oregon State University, and his Doctor of Medicine degree from the Loma Linda University School of Medicine in California. He also holds a Master’s degree in Public Health. He is board certified by the American Board of Anti-Aging Medicine where he has also served as a board examiner. Dr. Lam is a pioneer in using nontoxic, natural compounds to promote the healing of many age-related degenerative conditions. He utilizes optimum blends of nutritional supplementation that manipulate food, vitamins, natural hormones, herbs, enzymes, and minerals into specific protocols to rejuvenate cellular function.
Dr. Lam was first to coin the term, ovarian-adrenal-thyroid (OAT) hormone axis, and to describe its imbalances. He was first to scientifically tie in Adrenal Fatigue Syndrome (AFS) as part of the overall neuroendocrine stress response continuum of the body. He systematized the clinical significance and coined the various phases of Adrenal Exhaustion. He has written five books: Adrenal Fatigue Syndrome - Reclaim Your Energy and Vitality with Clinically Proven Natural Programs, The Five Proven Secrets to Longevity, Beating Cancer with Natural Medicine (Free PDF version), How to Stay Young and Live Longer, and Estrogen Dominance. In 2001, Dr. Lam established www.DrLam.com as a free, educational website on evidence-based alternative medicine for the public and for health professionals. It featured the world’s most comprehensive library on AFS. Provided free as a public service, he has answered countless questions through the website on alternative health and AFS. His personal, telephone-based nutritional coaching services have enabled many around the world to regain control of their health using natural therapies.
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