Clue: Lowly man ruined, ending in gutter (10)
Answer: PAWNBROKER
Explanation: Definition: Lowly man ruined, ending in gutter
 PAWN(a lowly man/one with low status and used by others) + BROKE(ruined/bankrupt) + **last letter of**(ending in) "gutter".
Defn: A cryptic definition, I presume, with the solution being the one who did the ruining of others.