Luiz is out of contract at Arsenal in the summer and looks set to leave on a free transfer.
Arteta sung the Brazilian’s praises at the end of January following the departures of experienced defenders Shkodran Mustafi and Sokratis Papastathopoulos.
Arteta highlighted the importance of Luiz in the dressing room, especially on the younger players.
Arteta said: “This season has been really tough in the beginning because he’s been through some injuries but he’s kept at it, he understood his role, he knows his role in the team, he’s one of our leaders and he’s so willing to keep improving.
“He knows the things that he’s really good at and the things where there is still room for improvement.