TOKYO, May 10 (Xinhua) -- Tokyo stocks closed higher Thursday on improved investor sentiment following Wall Street's positive overnight lead and on solid domestic corporate earnings released recently.

The 225-issue Nikkei Stock Average added 88.30 points, or 0.39 percent, from Wednesday to close the day at 22,497.18.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, gained 4.71 points, or 0.27 percent, to finish at 1,777.62.

Investors were encouraged from early trade by U.S. shares advancing overnight, local brokers said, adding that solid corporate earnings by domestic bellwether firms added to an upbeat mood during trading hours.

Some equity strategists pointed out however that the market stayed top-heavy during the day owing to a former aide to Prime Minister Shinzo Abe giving unsworn testimony in the Diet on matters related to a cronyism scandal implicating the prime minister.

By the close of play, mining, transportation equipment, and oil and coal product-linked issues comprised those that gained the most, and rising issues just outpaced falling ones by 991 to 989, on the First Section, while 103 ended the day unchanged.

On the main section on Thursday, 1,542.44 million shares changed hands, dropping from Wednesday's volume of 1,727.43 million shares.

The turnover on the penultimate trading day of the week came to 2,630.8 billion yen (23.93 billion U.S. dollars).