My Husband And I Had Health Rewards Check Up Few

My husband and i had health rewards check up few wks ago and his AST(SGOT)/ALT IS HIGH...so he is going to see specialist next wk. but i want to understand more on how he got that level high? he doesn't drink, smoke or take drugs except when he has flu or cold...how do we lower the number? AST is 431 and ALT is 824 not sure what those # means..all I know is that they are high