J.C. Penney Co Inc posted a lower quarterly profit on Friday as efforts to contain costs and trim inventory failed to overcome a decline in sales, and its shares fell 5 percent before markets opened.

Penney's net profit was $25 million, or 11 cents per share, in the fiscal first quarter that ended May 2, compared with a profit of $120 million, or 54 cents per share, a year earlier.

Sales fell 5.9 percent to $3.88 billion, while sales at stores open at least one year fell 7.5 percent.

Penney is one of many retailers facing steep sales declines in recent months as shoppers back off from spending on non-essential items in the recession. Such consumer thrift has hurt the department store sector.

Penney shares were down to $25.30 from Thursday's close of $26.65 on the New York Stock Exchange.

(Reporting by Aarthi Sivaraman; Editing by Derek Caney)