The veteran defensive end announced his retirement in an Instagram post Tuesday.
"I've been back and forth on my future playing football and after coming to a conclusion I will be stepping away from the game of football," Horton wrote. "I've made this decision off two reasons. The first is my overall health. The little injuries I've accumulated over the years have finally caught up to me and when weighing the risk, I'd rather preserve what's left of my body. Second reason being the conviction Christ has put on my heart to help teach and mentor the next generation."
Horton added that he will transition to coaching defensive line and "to help these next generation of rushers" at his alma mater Notre Dame High School in Sherman Oaks, California.
Undrafted out of USC, Horton, 30, spent seven seasons in Carolina, playing 83 games and starting 35. The defensive end will leave the game with 15.5 sacks, 24 QB hits and seven forced fumbles. Horton briefly spent time with the rival New Orleans Saints in 2019 before signing back with the Panthers, with whom he played six games and logged four tackles in his final season as a professional.
On the other side of the ball, Carolina re-signed running back Reggie Bonnafon to a one-year deal in 2020. Bonnafon was set to be an exclusive rights free agent, but will instead spend next season with the Panthers. In his second season in the NFL, Bonnafon picked up 173 total yards and a touchdown on 22 touches.
In other transaction news, the Miami Dolphins re-signed receiver Ricardo Louis to a one-year contract extension in 2020, a source told NFL Network's Tom Pelissero. The 25-year-old wideout missed both the 2018 and 2019 seasons with neck and knee injuries, respectively.