This looks to be a good article (PDF, by Marco Baretta, University of Bologna, 2009) about Leonardo da Vinci and includes history and reception of De Rerum Natura in Italy.
Excerpt:
QuoteDisplay MoreAware of the difficulties that may be encountered in any research on sources,
in this examination of the ties between Leonardo and Lucretius I have adopted
an approach that is intended to circumvent at least some of the obstacles men-
tioned above. While I have sought to identify the significant correspondences
between passages written by the two, it seemed to me necessary first and fore-
most to demonstrate that Lucretius was such a well-known author in the circles
frequented by Leonardo in Florence and Pavia that it would have been difficult,
if not impossible, for the artist to have remained unaware of the discussions of
certain themes that had been sparked by the diffusion of the poem. Therefore,
the historical and intellectual context in which Leonardo moved will form the
basis here for an interpretation of the text.