title: Salamander-derived, human-optimized nAG protein suppresses collagen synthesis and increases collagen degradation in primary human fibroblasts.
abstract: Unlike humans, salamanders regrow their amputated limbs. Regeneration depends on the presence of regenerating axons which upregulate the expression of newt anterior gradient (nAG) protein. We had the hypothesis that nAG might have an inhibitory effect on collagen production since excessive collagen production results in scarring, which is a major enemy to regeneration. nAG gene was designed, synthesized, and cloned. The cloned vector was then transfected into primary human fibroblasts. The results showed that the expression of nAG protein in primary human fibroblast cells suppresses the expression of collagen I and III, with or without TGF- β 1 stimulation. This suppression is due to a dual effect of nAG both by decreasing collagen synthesis and by increasing collagen degradation. Furthermore, nAG had an inhibitory effect on proliferation of transfected fibroblasts. It was concluded that nAG suppresses collagen through multiple effects.
authors.affiliation: Department of Surgery, King Saud University, Riyadh, Saudi Arabia ; College of Medicine Research Center, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Mohammad M
authors.initials: MM
authors.lastname: Al-Qattan
authors.forename: Medhat K
authors.initials: MK
authors.lastname: Shier
authors.forename: Mervat M
authors.initials: MM
authors.lastname: Abd-Alwahed
authors.forename: Ola H
authors.initials: OH
authors.lastname: Mawlana
authors.forename: Mohammed S
authors.initials: MS
authors.lastname: El-Wetidy
authors.forename: Reginald S
authors.initials: RS
authors.lastname: Bagayawa
authors.forename: Hebatallah H
authors.initials: HH
authors.lastname: Ali
authors.forename: May S
authors.initials: MS
authors.lastname: Al-Nbaheen
authors.forename: Abdullah M
authors.initials: AM
authors.lastname: Aldahmash
mesh_terms: D029845:Amphibian Proteins / Q000235:genetics*; D000818:Animals; D049109:Cell Proliferation; D003094:Collagen / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D005121:Extremities / Q000254:growth & development*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D059748:Proteolysis; D012038:Regeneration; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D014562:Caudata / Q000235:genetics
chemical_list: D029845:Amphibian Proteins; D053773:Transforming Growth Factor beta1; D003094:Collagen