Tribune Co. said Tuesday that its Chicago subsidiary has acquired Naperville Magazine, a lifestyle monthly devoted to the Illinois suburb of the same name.

The media company did not say how much it is paying Oster Communications LLC for the magazine, which was founded in 2005 and has built a circulation of 30,000.

The magazine’s publisher, Leah Rippe, will report to Chicago magazine publisher Rich Gamble.

In a statement, Gamble said the deal will give the company’s advertisers another option for targeting affluent, educated readers.

The privately-held company as a whole, which also counts the Chicago Tribune and the Los Angeles Times among its stable of newspapers, has been struggling with declines in print advertising. It filed for Chapter 11 protection in December 2008, unable to keep up payments on its debt.