NEW YORK (AP) -- A JPMorgan analyst downgraded shares of Martha Stewart Living Omnimedia Inc., citing a difficult advertising environment and the recent departure of Chief Executive Susan Lyne.

Michael Meltz lowered Martha Stewart to "Neutral" from "Overweight" in a client note Wednesday. The tone coming from the advertising market has worsened in recent months, he said, citing rival Meredith Corp.'s June 5 announcement predicting lower full-year earnings due to reduced advertising revenue.

In addition, Meltz called Lyne's Wednesday departure "disappointing," even if it was unsurprising.

"Since becoming CEO in 2004, Lyne has helped turn around the company -- by reinvigorating Martha Stewart Living, launching an aggressive online strategy and signing important merchandising partnerships," he said.

Still, he was optimistic on co-CEOs Wenda Harris Millard and Robin Marino. He left his profit estimates and $10 price target unchanged.

Martha Stewart Omnimedia Chairman Charles Koppelman dismissed Meltz's prediction of a weaker advertising market in an interview, saying those fears are overblown.

"There is no other company that has the media that we have and that has the merchandise and product side that we have, and because of that we are almost a recession-proof business," he said.

Shares of Martha Stewart Omnimedia rose 4 cents to $7.54 on Thursday. The stock has traded between $5.22 and $18.28 in the last 52 weeks.