Erythropoietin


 Erythropoietin (EPO), also known as red blood cell stimulating factor and erythropoietin, is a human endogenous glycoprotein hormone that stimulates red blood cell production. Hypoxia can stimulate the production of erythropoietin. Recombinant human erythropoietin has been used clinically for the treatment of anemia associated with renal insufficiency, acquired immunodeficiency syndrome/AIDS itself or treatment-induced anemia, malignant tumors. Anemia caused by anemia and rheumatism anemia.

Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with the peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. Liver production predominates in the fetal and perinatal period; renal production predominates in adulthood.

Exogenous erythropoietin, recombinant human erythropoietin (rhEPO) is produced by recombinant DNA technology in cell culture and are collectively called erythropoiesis-stimulating agents (ESA): two examples are epoetin alfa and epoetin beta. ESAs are used in the treatment of anemia in chronic kidney disease, anemia in myelodysplasia, and in anemia from cancer chemotherapy. Risks of therapy include death, myocardial infarction, stroke, venous thromboembolism, and tumor recurrence. Risk increases when EPO treatment raises hemoglobin levels over 11 g/dL to 12 g/dL: this is to be avoided.

rhEPO has been used illicitly as a performance-enhancing drug.It can often be detected in blood, due to slight differences from the endogenous protein; for example, in features of posttranslational modification.

Aliases EPO, EP, MVCD2, erythropoietin, Erythropoietin, ECYT5, DBAL
External IDs OMIM: 133170 MGI: 95407 HomoloGene: 624 GeneCards: EPO

Risks and side effects with EPO

Just like with steroids – you should use it wisely. Inappropriate usage might be dangerous if not fatal, but proper one eliminates all the risks or lowers it to the affordable level. Nowadays, we gained enough experience and stats to know how to avoid the problems.

The reason that EPO, and transfusion blood doping, might be dangerous is because of increased blood viscosity. Basically, whole blood consists of red blood cells and plasma (water, proteins, etc.). The percentage of whole blood that is occupied by the red blood cells is referred to as, the hematocrit. A low hematocrit means dilute (thin) blood, and a high hematocrit mean concentrated (thick) blood. Above a certain hematocrit level whole blood can sludge and clog capillaries. If this happens in the brain it results in a stroke. In the heart, a heart attack. Unfortunately, this has happened to several elite athletes who have used EPO in 80es.

EPO use is especially dangerous to athletes who exercise over prolonged periods. A well-conditioned endurance athlete is more dehydration resistant than a sedentary individual. The body accomplishes this by several methods, but one key component is to “hold on” to more water at rest. Circulating whole blood is one location in which this occurs and, thus, can function as a water reservoir. During demanding exercise, as fluid losses mount, water is shifted out of the blood stream (hematocrit rises). If one is already starting with an artificially elevated hematocrit then you can begin to see the problem – it is a short trip to the critical “sludge zone” (so drink enough liquids and don’t forget about aspirin!).

Additional dangers of EPO include sudden death during sleep, which has killed approximately 18 pro cyclists in the past fifteen years, and the development of antibodies directed against EPO. In this later circumstance the individual develops anemia as a result of the body’s reaction against repeated EPO injections (so do not use for longer than 6 weeks! and do not use through the whole year, do it 1-2 times before the most important competitions).

There are also a number of side effects associated with general use of this substance. Most notable, blood pressure can begin to rise as cell volume changes. This can reach the point of headaches and high blood pressure, obviously an unwanted effect. Additionally, flu-like symptoms, aching bones, chills and injection site irritations are also possible. Since athletes are not using this product for a medical condition, a strong incidence of side effects should be an indicator to discontinue using the drug. Clearly one should not wish to compromise their health for an athletic push.

EPO Dosage and Usage

Weekly dosage varies 50-300 IU per kilogram of body weight. By this guideline a 176 lb (80 kgs) athlete would take a maximum of 4000 U per injection. This would be done in the days/weeks prior to a competition, the peak effect hopefully reached near the day of the event. Sportsmen starts feeling results after two weeks of usage (hematocrit level increases 3-4%). Most of specialists agree that one should not use erythropoietin for more than six weeks!

We find it optimal to use following schedule: Loading phase 4500-12000 IU for week 1-3 (6000 IU in average), then keep supportive dosage 3000-4000 IU for weeks 4-6. Weekly dosage is to be split on three equal shots.

Also one can use this formula: 20-30 IU per kg for every shot (three shots a week). Conservative approach is 4500 IU / week (3 shots x 1500 IU) with 3000 IU supportive dosage (3 shots x 1000 IU).The higher dosage is – the more effect and more risks you gain. Anyway, it depends on the personal characteristics, base levels, target goals desired. Blood tests recommended if you’re toying with higher doses.

Take one tab of aspirin two times a day after meal or along with milk to prevent stomach damages (milk neutralizes aspirin acids). Aspirin will decrease blood viscosity thus decreasing risks of thrombosis which could be fatal during the long race due to sweating and extreme dehydration.

In general, greater dosages of rhEPO induce a quicker response of increased erythropoiesis than lower dosages, however, they are more likely to be detectable by doping tests. If athlete is not in a rush, it’s better to make three shots a week – peak form will be achieved anyway.