HAS1 and ischemic stroke: Increased synthesis of total HA and low molecular mass 3–10 disaccharides of HA (o‐HA) in the serum of patients with ischemic stroke (1, 3, 7, and 14 days) and postmortem tissues has been reported in prior investigations, mainly attributed to overexpression of HA synthases (HAS1 and HAS2) and hyaluronidases in inflammatory cells in peri‐infarcted areas of the cerebral tissue [7].