Actresses Chandra Wilson and Sandra Oh ran the 5K race in the annual Kaiser Permanente Rock 'n' Roll Half Marathon.
Proceeds from the event benefit CureMito!, a nonprofit group that supports people with the cell disorder known as mitochondrial disease and raises funds for research.
Wilson's daughter Sarina was diagnosed with a type of mitochondrial dysfunction, according to the CureMito! website, which also states Wilson is an ambassador for the group.
The actress said she hopes to bring mitochondrial disease into the mainstream.
"We had a great showing last year. We're looking to double our showing this year to raise awareness and funds, of course, to help continue to do research and treatment for mitochondrial disease," Wilson told Eyewitness News.
Oh also came out to support Wilson's daughter, who she says she's known since Sarina was just 10 years old.
Sections of Arroyo and Colorado boulevards, Lake and Wilson avenues and the 134 Freeway on- and off-ramps at Orange Grove Avenue are among the streets blocked during the race, which starts and ends at the Rose Bowl. The street closures were set to be in effect until noon.
For a list of street closures, visit http://runrocknroll.competitor.com/pasadena.