INS and diabetes mellitus: The second mechanism associated with decreased cardiac collagen content in our work may be related to improved insulin sensitivity (Fig. 2b). In fact, type 2 diabetes mellitus (T2DM) is an independent risk factor for cardiac remodeling39. In addition, many studies have already shown that IR or T2DM are able to promote changes in cardiac tissue, namely: mitochondrial dysfunction, decreased sensitivity to Ca2+, oxidative stress, apoptosis, necrosis and increased collagen in the interstitial space47–49.