Sclerosteosis is an autosomal recessive disorder characterized by bone overgrowth. It was first described in 1958 but given the current name in 1967. Excessive bone formation is most prominent in the skull, mandible and tubular bones. It can cause facial distortion and syndactyly. Increased intracranial pressure can cause sudden death in patients. It is a rare disorder that is most prominent in the Afrikaner population in South Africa (40 patients), but there have also been cases of American and Brazilian families. Cause
Sclerosteosis is caused by mutations in the gene that encode for the sclerostin protein. The sclerostin protein is necessary in inhibiting canonical wnt signalling. Wnt signalling results in increased osteoblast activity and RANKL synthesis, sclerostine therefore increases boneformation by indirectly inhibiting RANKL synthesis and thus osteoclast activitation. References
External links
These Superhumans Are Real and Their DNA Could Be Worth Billions
Sclerostin Inhibition in the Management of Osteoporosis
Effect of bone thickening on the skull area: need of skull removal
The thickened mucus can lead to inflammation, respiratory infections, and clogged ducts. Mechanism of action
Elexacaftor/tezacaftor/ivacaftor is a tridrug treatment in which the medications work together to increase the transport of chloride and sodium ions, and reducing thick mucus production. CFTR channel potentiator
Ivacaftor is a selective small-molecule potentiator of the CFTR protein that increases the proteins ability to open chloride channels. Its effectiveness is highly dependent on the amount of CFTR protein at the cell surface and the responsiveness of the mutant CFTR protein. Ivacaftors primary target is to treat class III CFTR gating mutations like G551D as well as other less common mutations. In the crystalline figure, you can see ivacaftor, shown as a gray ball and stick model on the bottom-right, bound to CFTR docked in a cleft formed by transmembrane helices at the protein-lipid interface. CFTR correctors
Elexacaftor and Tezacaftor act as CFTR correctors to repair F508del processing by binding to the CFTR protein to increase the availability of CFTR protein on the cell surface. They work by modulating the position of the CFTR protein into the right position on the cell surface.The combination of increased CFTR protein in the correct position on the cell surface with ivacaftors potentiation of chloride channel opening results in increased transport of chloride and thinned mucus secretions. Pharmacokinetics
Elexacaftor/tezacaftor/ivacaftor is primarily metabolized by CYP3A4 /5. This medication should be taken with a high fat meal to improve absorption through the gut. It is excreted as metabolites or unchanged mainly through feces and to a smaller extent urine.