Transgenic overexpression of heat shock protein 72 in mouse muscle protects against exhaustive exercise-induced skeletal muscle damage.

BACKGROUND/PURPOSE: Lifelong overexpression of heat shock protein (HSP) 72 in skeletal muscle is known to protect against age-related oxidative stress and muscle damage. This study aimed to ascertain whether exhaustive exercise (EE)-induced muscle fatigue and damage can be prevented by lifelong overexpression of HSP72 in skeletal muscle. METHODS: Transgenic mice heterozygous for the porcine HSP70.2 gene ([+]HSP72) and transgene-negative littermate controls ([-]HSP72) were subjected to an EE protocol. Mice were randomly divided into four groups: sedentary [-]HSP72, sedentary [+]HSP72, EE [-]HSP72, and EE [+]HSP72. Animals were killed 82 minutes after the start of EE to determine muscular levels of HSP72, serum levels of superoxide dismutase (SOD, an antioxidant enzyme) and lactate (an indicator of muscle fatigue), muscular levels of matrix metalloproteinase (an indicator of inflammatory myopathies), and muscular damage. RESULTS: During the test, the latency value for the occurrence of EE was 79-85 minutes and 100-110 minutes for [-]HSP72 and [+]HSP72 mice, respectively. After EE, [+]HSP72 mice had significantly higher serum SOD and significantly lower serum lactate, muscular matrix metalloproteinase or myeloperoxidase activity, and muscle damage compared to [-]HSP72 mice. CONCLUSION: The results suggest that HSP72 overexpression in skeletal muscle may improve muscle fatigue and damage in EE by reducing oxidative damage and phagocytic infiltration, at least in mice.

The European Medicines Agency review of eltrombopag (Revolade) for the treatment of adult chronic immune (idiopathic) thrombocytopenic purpura: summary of the scientific assessment of the Committee for Medicinal Products for Human Use.

On 11(th) March 2010, the European Commission issued a marketing authorization valid throughout the European Union for Revolade for the treatment of adult chronic immune (idiopathic) thrombocytopenic purpura. Revolade is an orphan medicinal product indicated for splenectomized patients with immune (idiopathic) thrombocytopenic purpura who are refractory to other treatments (e.g. corticosteroids, immunoglobulins) and as second-line treatment for non-splenectomized patients where surgery is contraindicated. The active substance of Revolade is eltrombopag (ATC code B02BX05). Eltrombopag increases platelet production through activation of the thrombopoietin receptor. The recommended oral dose is 50 mg once daily to achieve and maintain a platelet count of the 50×10(9)/L or more necessary to reduce or prevent the risk of bleeding. The benefit of Revolade is a durable response in maintaining platelet levels. The most common side effects include headache, nausea, hepatobiliary toxicity, diarrhea, fatigue, paresthesia, constipation, rash, pruritus, cataract, arthralgia and myalgia. The decision to grant the marketing authorization was based on the favorable recommendation of the Committee for Medicinal Products for Human Use of the European Medicines Agency. The objective of this paper is to describe the data submitted to the European Medicines Agency and to summarize the scientific review of the application. The detailed scientific assessment report and product information, including the summary of product characteristics, are available on the European Medicines Agency website (www.ema.europa.eu).