Hydrogels composed of bovine collagen type I (COLI) and low molecular weight hyaluronic acid (LMWHA) or COLI and PEG could control the release of active AD-MSC secretome, counteracting 6-OHDA toxicity while upregulating antioxidant enzymes Sirtuin 3 (SIRT3) in a neurodegeneration-related experimental setting (Chierchia et al., 2020). Here, SIRT3 is linked to Alzheimer disease.