The sale of several properties helped Duke Realty Corp. record strong earnings in the first quarter, the Indianapolis-based real estate investment trust announced Thursday morning.

Duke reported a profit in the three-month period of $47.6 million, or 19 cents a share, compared with a loss of $15.3 million, or 7 cents a share, in the same quarter a year earlier.

Revenue increased 19 percent, to $386.9 million.

Sales of properties totaling 2 million square feet generated $456 million overall and gains of $79.5 million, the company said. Nearly $275 million was generated by the sale of 13 office buildings located mostly in the Midwest to an existing joint venture with Los Angeles-based CB Richard Ellis.

“These dispositions in combination with our industrial acquisitions over the last few quarters are a major step in achieving our asset strategy,” Duke Realty CEO Dennis D. Oklak said in a prepared statement.

The company has undertaken a strategy to shed a slew of office space within its portfolio of properties in favor of industrial investments.

Duke Realty reported first-quarter funds from operations, a key measure for REITs, of $71.8 million, or 27 cents a share, compared with FFO of $63.9 million, or 28 cents a share, in the prior-year period.

Adjusted for preferred share buybacks, FFO for the quarter was 28 cents a share, the company said.

The company reaffirmed its 2011 FFO of between $1.06 and $1.18.

The occupancy rate for Duke Realty’s portfolio of projects, including those under development, was 88.9 percent at the end of March, down slightly from 89.1 percent at the end of December.

The price of company shares has increased nearly 50 percent since they hit a 52-week low of $10.19 in December. Shares opened trading Thursday morning at $15.21, down slightly from a 52-week high of $15.26 reached on Monday.