Current liver research: mechanism of inflammation-induced anemia

19 September 2016

In case of an anemia, organs suffer from oxygen deficiency. The shortage occurs because the number of red blood cells as oxygen carriers is reduced. Classic symptoms of anemia include fatigue, lack of concentration, headache, dizziness, as well as heart palpitations and shortness of breath. Anemia can have many causes. Very commonly, it is associated with acute and chronic inflammation, but so far the mechanisms of their interaction are not well understood.

Israeli scientists led by Prof. Eithan Galun, also head of CRC 841 project C3 and visiting scientist at University Medical Center Hamburg-Eppendorf, have now put a key piece of the anemia puzzle in place. They could show that smallest nucleic acid chains, the microRNA miR-122, generated by the liver and secreted into the blood, are involved in the development of anemia asscoiated with inflammation. miR-122 reaches the kidney and reduces the expression of the hormone erythropoietin (EPO), which stimulates red blood cell production in the bone marrow in a healthy body. Conversely, upon reducing miR-122 levels, the scientists could reverse anemia. The observations are the first to show a direct link between a microRNA and inflammation-induced anemia and may constitute a basis for a novel and promising therapeutic approach to reduce the development or progression of anemia in patients with inflammation. The study is published in the renowned journal Gastroenterology (Rivkin et al. 2016).

The scientists demonstrated the key role of the liver-specific miR-122 in various models of inflammation. In cooperation with other CRC 841 projects (B3 & B7)), they also analyzed human samples from the CRC 841 Liver.Net Biobank, which provides anonymised samples from patients with liver disease for research purposes.

Publication:

Rivkin M, Simerzin A, Zorde-Khvalevsky E, Chai C, Yuval JB, Rosenberg N, Harari-Steinfeld R, Schneider R, Amir G, Condiotti R, Heikenwalder M, Weber A, Schramm C, Wege H, Kluwe J, Galun E, Giladi H

Inflammation-Induced Expression and Secretion of MicroRNA 122 Leads to Reduced Blood Levels of Kidney-derived Erythropoietin and Anemia
Gastroenterology. 2016 Jul 28. pii:S0016-5085(16)34827-2. doi: 10.1053/j.gastro.2016.07.031. [Epub ahead of print]