Civil rights leader Rev. Jesse Jackson Sr. has been diagnosed with Parkinson's disease.
In a statement, Jackson said: "For me, a Parkinson's diagnosis is not a stop sign, but rather a signal that I must make lifestyle changes and dedicate myself to physical therapy in hopes of slowing the disease's progression."
Working closely with other civil rights leaders like Rev. Dr. Martin Luther King Jr., Jackson was a key figure during the 1960s civil rights movement.
In the 1980s, Jackson transitioned into politics when he ran for the Democratic nomination for president twice. Many say his campaigns paved the way for African-Americans in U.S. politics.
In 2008, Democrat Donna Brazile referred to Jackson as "my political father."
On Instagram, Rev. Al Sharpton responded to Jackson's diagnosis and praised his work.
"He changed the nation. He served in ways he never got credit. No one in our lifetime served longer and stronger," Sharpton said.
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