In a run-down area youth-leader found refuge (6)
I believe the answer is:
asylum
'refuge' is the definition.
(synonyms)
'in a run-down area youth-leader' is the wordplay.
'in' means one lot of letters goes inside another.
'run-down area' becomes 'slum' (I've seen this in another clue).
'youth leader' becomes 'y' (I've seen this in other clues).
'a'+'slum'='aslum'
'aslum' enclosing 'y' is 'ASYLUM'.
'found' is the link.
(Other definitions for asylum that I've seen before include "'Refuge, sanctuary (6)'" , "Place of shelter or refuge" , "Refuge or home for mentally ill" , "Harbour" , "Madhouse" .)