Both dystrophins retain the actin-binding, cysteine-rich (Cys), and C-terminal domains of normal, full-length dystrophin (14 kb). Exon 52 (the number of bases is not a multiple of 3) is absent from pre-m RNA, which results in a misalignment of the reading frame after splicing (out-of-frame); this leads to a premature stop codon in the following exon of the m RNA.Tags: 30th Australia-Japan Relations Essay 2012Life Didactic EssayEssay ReflectivePay Someone To Write An EssayBusiness Plan For A Retail StoreCare Work Training CoursesIndependent Film Business PlanUntraceable Term PapersHow To Write A Company Description For A Business PlanNorthrop Frye Four Essays
Furthermore, it usually resolves by stopping statin treatment.
Many physicians and some scientists hold the view that statins should not be prescribed for people with any muscle disease. As you might guess, we had some difficulty getting our paper published because of this concern. Whitehead: A moderate human dose of simvastatin was administered to mice at different stages of the disease and produced considerable improvements in overall muscle health and physiological function.
The severity of statin-induced myopathy ranges from muscle pain (often not due to statins, as it turns out) to muscle weakness to a severe necrotizing myopathy.
The latter is quite serious but fortunately is very rare.
As a result, a truncated but functional dystrophin is produced, resulting in a mild dystrophic phenotype.
Whitehead: In addition to their well established cholesterol lowering benefits, statins also have potent anti-inflammatory, anti-fibrotic and antioxidant effects, which continue to be identified in a wide range of diseases.Normal muscle regenerates effectively following exercise-induced damage, however in DMD, there is a chronic inflammatory response, which impedes regeneration and promotes the progressive replacement of healthy muscle tissue with fibrotic scar tissue.Together, these pathogenic processes reduce muscle force production, which first causes loss of mobility by the age of 10-15 and eventually weakens the respiratory muscles and heart, leading to death by 20 to 30 years of age. Froehner: In a relatively small percentage of cases, statins themselves cause a myopathy.Figure 1 Hypothetical pathogenic mechanism of dystrophin deficiency.Dystrophin deficiency causes sarcolemmal disruption and calcium channel activation by mechanical stress.Rather, pharmacological agents such as simvastatin could potentially provide an inexpensive, readily available, treatment for DMD. Froehner: As Nick said, our published data on simvastatin is very robust.After consulting with several people who have experience in trials, we think a clinical trial in DMD boys is the next step. Froehner: That depends on the results of clinical studies.() Exon 51-skipping therapy for exon 52-deleted DMD.Exon 51 is skipped by AO (sum of deleted bases is a multiple of 3) in pre-m RNA; subsequently, the reading frame is corrected in m RNA (in-frame) and translation progresses normally. Becker muscular dystrophy exhibits a milder phenotype, having mutations that maintain the reading frame and allow for the production of truncated dystrophin.Minidystrophin is a dystrophin of mild BMD patients that is ~6.4 kb in size.Based on this, the rod region was further truncated to create microdystrophin (4.9 kb) that can be incorporated into viral vectors.