G ) ▁production ▁is ▁up ▁reg ulated ▁in ▁re active ▁ast ro cy tes ▁as ▁part ▁of ▁gli al ▁scar ▁formation . ▁K SP G s ▁have ▁also ▁been ▁shown ▁to ▁in hib it ▁neur ite ▁out g row th ▁extension , ▁limit ing ▁n erve ▁reg ener ation . ▁Ker atan ▁sul f ate , ▁also ▁called ▁ker atos ulf ate , ▁is ▁formed ▁from ▁repeating ▁dis ac char ide ▁gal act ose ▁units ▁and ▁N - ac et yl gl uc os am ines . ▁It ▁is ▁also ▁ 6 - s ulf ated . ▁This ▁sul f ation ▁is ▁cru cial ▁to ▁the ▁el ong ation ▁of ▁the ▁ker atan ▁sul f ate ▁chain . ▁A ▁study ▁was ▁done ▁using ▁N - ac et yl gl uc os am ine ▁ 6 - O - s ulf otr ans fer ase - 1 ▁def ic ient ▁m ice . ▁The ▁wild ▁type ▁mouse ▁showed ▁a ▁significant ▁up ▁reg ulation ▁of ▁m R NA ▁express ing ▁N - ac et yl gl uc os am ine ▁ 6 - O - s ulf otr ans fer ase - 1 ▁at ▁the ▁site ▁of ▁cort ical ▁injury . ▁However , ▁in ▁the ▁N - ac et yl gl uc os am ine ▁ 6 - O - s ulf otr ans fer ase - 1 ▁def ic ient ▁m ice , ▁the ▁expression ▁of ▁ker atan ▁sul f ate ▁was ▁significantly ▁decre ased ▁when ▁compared ▁to ▁the ▁wild ▁type ▁m ice .