The Aging Reversal Experiments and GHK
The discovery of GHK-Cu arose from studies on human aging and a search for methods to reverse certain deleterious biochemical changes that occur with aging and are intensified in heart attack survivors. The initial target was to find methods of reducing the concentration of the blood protein fibrinogen. Elevated blood fibrinogen reduces blood flow through the tissues and raises the death rate.
Studies on fibrinogen metabolism concluded that there were factors in the blood protein albumin fraction that reduced fibrinogen synthesis and strongly stimulated liver metabolism. Some of these effects were due to albumin-bound free fatty acids but analysis of this albumin fraction found a tripeptide-copper complex (GHK-Cu) that improved liver cell metabolism and survival in culture. The plasma concentration of GHK-Cu was higher in men of age 20 ( ~200 ng/ml) than in men of age 70 ( ~80 ng/ml). Ultimately, this tripeptide copper complex (GHK-Cu) was found to have multiple actions that activated tissue regeneration and remodeling. The improvement of skin quality and turnover in older persons by application of GHK-Cu could be considered an aging reversal effect.
|Observation and Question Asked||Type of studies||Assumed Cause at Start of Studies. Result/Actual Cause||References|
|Human blood fibrinogen levels increase with age and disease - This increases blood coagulation and is associated with a sharply increased death rate.
Why was the fibrinogen increased?
|Human fibrinogen turnover studies||
Expected cause - Fibrinogen was not being used and accumulated in the blood
Actual cause - Human fibrinogen turnover studies found that the blood increase was due to an increased liver synthesis of the protein in older persons and heart attack survivors.
|Pilgeram LO, Pickart, L Bandi, Z, Fatty acid control of fibrinogen turnover in aging and atherosclerosis. 7th International Congress of Gerontology, June 1964, pp. 451-460. Pickart L, Pilgeram LO. The role of thrombin in fibrinogen biosynthesis. Thromb Diath Haemorrh. 1967 May 31;17(3-4):358-64. Pilgeram LO, Pickart L. Control of fibrinogen biosynthesis: the role of free fatty acid. J Atheroscler Res. 1968, 8:155-66.|
|Fibrinogen is synthesized in the liver.
Was the increased fibrinogen synthesis observed in older persons and heart patients due to changes in the liver or was it due to factors in the blood that perfused the liver?
|Measure fibrinogen synthesis in isolated human liver tissue from persons aged 20 to 30 and in persons aged from 60 to 80. Incubated the young (20-30) liver tissue with blood from either the young (20-30) or the old group (60-80). p (60-80)||
Assume cause - The increase in fibrinogen synthesis with age was due to changes in the liver tissue.
Actual cause - The increase in fibrinogen synthesis in the older persons was not due to changes in the liver tissue but almost totally due to factors in the older blood.
Pickart L, Thaler MM. Suppression of tumor-associated hyperfibrinogenemia and free fatty acidemia with p-phenoxybenzalbutyrate (clofibrate). Cancer Res. 1979 Oct;39(10):3845-8. Pickart, L. Fat metabolism, the fibrinogen/fibrinolytic system and blood flow: new potentials for the pharmacological treatment of coronary heart disease. Pharmacology 1981;23(5):271-80; Pickart L Suppression of acute-phase synthesis of fibrinogen by a hypolipidemic drug (clofibrate). Int J Tissue React. 1981 3(2):65-72.
|What is the factor(s) in the blood that stimulated or inhibited fibrinogen synthesis?||Studied the effect of various plasma protein fractions that affected fibrinogen synthesis in mice.||No. The albumin fraction of plasma had a suppressive action on fibrinogen synthesis that returned synthetic patterns to that of a younger person. Some effects appeared to be due to free fatty acids but this albumin fraction itself also stimulated liver cell metabolism.||Pickart L, Thaler MM. Fatty acids, fibrinogen and blood flow: a general mechanism for hyperfibrinogenemia and its pathologic consequences. Med Hypotheses. 1980 May;6(5):545-57. Pickart L, Thaler MM. Free fatty acids and albumin as mediators of thrombin-stimulated fibrinogen synthesis. Am J Physiol. 1976 Apr;230(4):996-1002.|
|What was the factor in the albumin fraction that stimulated liver metabolism?||Studies the protein albumin and various small molecules associated with the protein.||
Expected cause - The effects were due to the albumin molecule.
Actual cause - The effects were not due to albumin but rather due to a small peptide-metal complex associated with the protein.
|A tripeptide in human plasma that increases the survival of hepatocytes and the growth of hepatoma cells. Pickart Ph.D. Thesis in Biochemistry, University of California, San Francisco, 1973; Thaler MM, Pickart L Metabolic and growth promoting properties of serum tripeptide and its synthetic analog. In: Gene Expression and Carcinogenesis in Cultured Liver. (Academic Press, 1975) pp. 292-310.|
|What was the structure of the peptide-metal complex?||Isolation and chemical analysis.||The complex was composed of a tripeptide, glycyl-l-histidyl-l-lysine plus approximately equimolar copper 2+ or GHK-Cu||Schlesinger DH, Pickart L, Thaler MM. Related Articles, Protein Growth-modulating serum tripeptide is glycyl-histidyl-lysine. Experientia. 1977 Mar 15;33(3):324-5.|
|What was the function of GHK-Cu?||Synthesized variants of GHK-Cu that inhibited cell growth in cell culture, wound repair, and some tumors in animals.||During studies of growth inhibitory copper analogs of GHK-Cu on wound repair, it was observed that GHK-Cu, which was used as control substance, was healing wounds while the inhibitors stopped wound healing. It was concluded that GHK-Cu had a stimulatory action on wound healing.||Pickart L, Lovejoy S. Biological activity of human plasma copper-binding growth factor glycyl-L-histidyl-L-lysine. Methods Enzymol. 1987;147:314-28.|