The sources did not indicate a reason for the departure.
The news comes on the heels of Carano's reemergence in mixed martial arts after an extended absence following her loss to Cristiane "Cyborg" Santos. After the loss in April 2009, Carano stepped away from the sport to work on potential movie roles and other opportunities outside of fighting.
She became a huge star for Strikeforce and appeared on the cover of ESPN the Magazine, featured in the video game Command & Conquer: Red Alert 3 and competed as Crush on the NBC television program American Gladiators.
During the Strikeforce: Fedor vs. Silva event in February, Carano announced her return to MMA. While a date or opponent was not mentioned, Carano did mention her intentions to return sometime this summer.
Carano had been a staple of Xtreme Couture for the majority of her mixed martial arts career.
Jackson's MMA could not be reached for comment.