Tributes Pour in for Playboy Founder Hugh Hefner

High-profile figures from the media world and beyond are paying tribute to Playboy magazine founder Hugh Hefner.

Playboy founder Hugh Hefner arrives at Stansted Airport on June 2, 2011 in Stansted, England. (Credit: an Kitwood/Getty Images)

Playboy founder Hugh Hefner arrives at Stansted Airport on June 2, 2011 in Stansted, England. (Credit: an Kitwood/Getty Images)

Playboy said late Wednesday that Hefner died from natural causes "surrounded by loved ones" at his Playboy Mansion home in Beverly Hills. He was 91.

Among the first to speak out was Hefner's son Cooper, who is now the chief creative officer of Playboy Enterprises.

"My father lived an exceptional and impactful life as a media and cultural pioneer and a leading voice behind some of the most significant social and cultural movements of our time in advocating free speech, civil rights and sexual freedom," he said in a statement.

Related: Playboy founder Hugh Hefner dead at 91

Celebrities and other public figures took to social media to pay their respects.

"Hugh Hefner was a strong supporter of the civil rights movement," tweeted the Rev. Jesse Jackson. "We shall never forget him. May he Rest In Peace."

Gene Simmons, the lead singer of Kiss, described Hefner as "a great man, entrepreneur and innovator."

"One of the nicest men I've ever known. Godspeed, Hugh Hefner," said Nancy Sinatra.

Comedian Richard Lewis said that few people did more than Hefner in terms of "breaking boundaries" for writers. He referenced the Playboy founder's support for comedian Lenny Bruce's legal battles over free speech.

Related: Hugh Hefner: A cultural icon who helped change the world

Hefner is survived by his 31-year-old wife, Crystal, and four grown children, Playboy said.

Cooper Hefner isn't the only one of them to have worked for the family business. Hefner's daughter, Christie, was CEO of Playboy Enterprises for more than 20 years.