The Los Angeles Business Journal’s index of largest local public companies fell slightly for the week as the broader markets also declined on news of higher oil prices.

The weighted LABJ Stock Index closed down 0.56 percent to 136.06 for the week ended Aug. 31. Gainers outnumbered decliners 100 to 67, with nine companies unchanged.

U.S. Auto Parts Networks Inc. was among the biggest decliners, falling 15 percent to $2.95. In a conference call, managers of the Carson e-commerce company announced a plan to shut down some of their sites to concentrate resources on a few large ones. The plan will reduce revenue by 13 percent over the next two years. An analyst at Barrington Research Associates later downgraded the company’s stock to “under perform” from “market perform” because of the announcement.

Spark Networks Inc., a dating site company based in Beverly Hills, fell 6 percent to $5.65 after the company announced the launch of Gospel Media Group, a set of new websites for the evangelical market, unrelated to dating.

Among gainers, Mannkind Corp. gained 13 percent to $2.70 following the announcement of a shelf registration to sell up to $500 million in company stock to raise additional capital. Also, Lionsgate Entertainment Corp. rose 8 percent after the Santa Monica studio secured a commitment from FX Network for an additional 90 episodes of Charlie Sheen’s comedy series “Anger Management.”