It turns out oxytocin is responsible for a lot more than just love. New science has found that this amazing molecule also influences how sociable each of us is, allowing us to 'tune in' to the social information around us, perceiving it in much higher resolution. Scientists are now applying this new knowledge in the lab, and as reporter Dr Graham Phillips finds out, they're discovering oxytocin's great potential to treat social disorders, like drug addiction and alcoholism.
Thymosin beta 4 is a small 43 amino acid protein (a peptide) that was originally identified in calf thymus, an organ that is central in the development of immunity. Tb4 was later found in all cells except red blood cells. It is highest in blood platelets that are the first to enter injured areas, in wound healing. Tb4 is also detected outside cells, in blood plasma and in wound and blister fluids.
In the end, despite three years of intense scrutiny, the drug at the centre of the investigation remains poorly understood. In this regard, it could serve as a reflection of the whole ordeal. Everyone has an opinion, often voiced with authority and conviction. The reality is that much of this complex narrative continues to be a mystery. Many would have been well served by the humble words of the Socratic paradox – “I know that I know nothing”.
Thymosins were discovered in the mid 1960’s, when Allan Goldstein from the Laboratory of Abraham White at the Albert Einstein College of Medicine in New York studied the role of the thymus in development of the vertebrate immune system. Since then, Dr. Goldstein founded a company that creates thymosin alpha 1 for the purpose of increasing immune cell activity, and thymosin beta 4 (TB-500) to promote wound repair and healing.
Again, the three groups of mice were exposed to the stressful experience of social defeat in the cages of other more aggressive mice. This time, six hours after the social stress, the mice were put in a box in which they received a brief electric shock, which startles them but is not painful. Then 24 hours later, the mice were returned to the same box but did not receive a shock.
The studies that have been conducted have determined that this peptide is potent and that it occurs totally naturally. It does help to repair wounds using its anti-inflammatory characteristics. Unlike with growth factors and other repair factors, this peptide increases the migration of endothelial and keratinocyte. It also does not conjoin to extracellular matrixes and is noted as having a molecular weight that is very low, which enables it to travel far distances within tissues.
Melanotan II first captured the public's imagination when the mainstream media briefly touted it as a Viagra-like panacea for middle-aged men. Norman Levine, a dermatologist who led the team that developed the drug, had first conducted experiments in which he darkened the pigments of frogs by injecting them with a hormone called Alpha MSH. After Melanotan II was modified for human use and put through clinical trials, Levine reported that "one very astute observer who took this drug told us that he was developing spontaneous erections."
In humans, the Tβ4 gene TMSB4X is localized to the X chromosome at Xq21.3–q22 (). The Tβ4 cDNA open reading frame contains an initial methionine codon followed by a codon for the N-terminal serine and, although cells secrete a certain amount of Tβ4, there is no hydrophobic signal sequence. The initial methionine residue of the nascent Tβ4 polypeptide is removed and the N-terminal serine residue is often acetylated in the cells.
The first study to show that Tβ4-promoted tissue repair was a dermal study performed in rats (Malinda et al., 1999). It had previously been found to promote angiogenesis and was reported to be high in platelets (Grant et al., 1995; Hannappel & van Kampen, 1987; Malinda, Goldstein, & Kleinman, 1997; Philp, Huff, Gho, Hannappel, & Kleinman, 2003). Since platelets are the first cells to enter a wound, it was clear that Tβ4 should be tested in dermal wounds in an animal model (Malinda et al., 1997, 1999; Philp, Badamchian, et al., 2003). In the first dermal study using 8 mm full-thickness punch wounds in rats, Tβ4 at 5 μg/50 μL of phosphate-buffered saline was found to accelerate wound closure, increase angiogenesis, and accelerate collagen deposition (Malinda et al., 1999). Tβ4 was only applied at the time of injury and at 48 h since after that the crust had formed. Visible macroscopic improvement was seen in the treated group by day 4. The study also found that Tβ4 promoted keratinocyte migration in vitro with activity in the picogram range. The findings were confirmed in various additional animal models (Table 1) and led to the clinical trials for hard to heal wound in patients as detailed in Table 2.
“The study was double-blinded and was for two consecutive 6-wk periods. No diet was prescribed during the first period, a 5040-kJ/d diet was recommended for the second. Significant weight loss was observed in 5-HTP-treated patients during both periods. A reduction in carbohydrate intake and a consistent presence of early satiety were also found. These findings together with the good tolerance observed suggest that 5-HTP may be safely used to treat obesity.”
Humans are social animals. Our individual prospects depend to a significant degree on the prospects of the group(s) to which we belong, and how well we get along with the group(s). Survival means being acutely sensitive to who is on our side and who is not. So it isn’t surprising that trust matters so much to how we go about protecting ourselves. And it isn’t surprising to find the instinct for trust rooted deep in the brain.
For depression: Most commonly, 150-800 mg daily is taken for 2-6 weeks. These doses are sometimes divided up and administered as 50 mg to 100 mg three times a day. Sometimes the dose starts out low and steadily increases every 1-2 weeks until a target dose is reached. Less commonly, higher doses are used. In one study, the dose is steadily increased up to 3 grams per day.
Nolen, W. A., van de Putte, J. J., Dijken, W. A., Kamp, J. S., Blansjaar, B. A., Kramer, H. J., and Haffmans, J. Treatment strategy in depression. II. MAO inhibitors in depression resistant to cyclic antidepressants: two controlled crossover studies with tranylcypromine versus L-5-hydroxytryptophan and nomifensine. Acta Psychiatr.Scand 1988;78:676-683. View abstract.
Potential side effects of 5-HTP include heartburn, stomach pain, nausea, vomiting, diarrhea, drowsiness, sexual problems, vivid dreams or nightmares, and muscle problems. Because 5-HTP has not been thoroughly studied in a clinical setting, possible side effects and interactions with other drugs are not well known. According to the US National Institute of Health TOXNET, 5-HTP has not been associated with serotonin syndrome or any serious adverse events in humans. Across multiple studies, 5-HTP also been reported to not cause any noticeable hematological or cardiovascular changes. 5-HTP also has not been associated with eosinophilia.