A top MySpace executive has decided to quit News Corp's social networking site after just four months at the job, the second high-profile departure in a year for the struggling company.

MySpace Co-President Jason Hirschhorn is leaving the company for personal reasons, News Corp's chief digital officer Jon Miller said in a statement.

His departure comes just months after he and co-President Mike Jones outlined an ambitious turnaround plan at the company's Beverly Hills headquarters, pulling back the curtain on a redesigned website that will focus more strongly on music and media content.

Hirschhorn -- a former key executive at Viacom's MTV network -- took over as co-president along with Jones in February, replacing then-CEO Owen Van Natta, who held the position less than a year.

News Corp acquired MySpace in 2005 for $580 million. Since the acquisition, the Internet site has lost ground to rival Facebook, which now ranks as the world's No.1 social network with about half a billion users.

Hirschhorn joined MySpace in April 2009 as Chief Product Officer. Miller said there were no plans to bring in additional management.

(Reporting by Carolina Madrid; Editing by Tim Dobbyn)