These "adipokines" are produced by fat tissue.
Have a peep if you have time at IL6 for example. It gives an insight as to how complex and inextricably interlinked this all is.
IL6 and TNF alpha are two that crop up quite often on this site.
I have found this really helpful.
http://adipocyte.co.uk/Adiposetissuepeptides.htm
RB