The 27-year-old was disappointed by the comments of his former CEO regarding Koln's decision to sign the striker in 2009 and told him to focus his attentions on his own team
The Germany international left Koln in 2006 for Bayern Munich but transferred back to the RheinEnergieStadion after three years with the Bavarian club.
Following his departure for Arsenal this summer, Podolski's former CEO released a parting shot at the forward, blaming him for encouraging a move that was against the Billy Goats' interest three years ago.
"When the club re-signed Lukas, it was about emotions, about Koln's role model. Then it was a well-considered signing. From today's view, the transfer wasn't profitable," Horstmann told Bild.
However, following a friendly fixture with his former club, in which Arsenal ran out 4-0 winners, the 27-year-old took the chance to issue a response to Horstmann's criticisms.
"I cannot understand why he said this. Horstmann should worry about the players he has in his squad now," Podolski told Sport1.
Koln will participate in the 2. Bundesliga this season after suffering relegation from the top flight last term.