Comparative in Vitro Study of the Effects Produced by Different Hyaluronic Acids on the Extracellular Matrix and Fibroblasts

—Hyaluronic acid (HA) has emerged as a pivotal molecule in medicine for various medical procedures. Its functionality, applications and the cellular response it triggers vary depending on its molecular weight, presentation and delivery method. The benefits ascribed to hyaluronic acid (HA) in aesthetic medicine have ignited current interest in studying its effects on fibroblasts. This interest stems from its classification as a biostimulant and biorevitaliser. A series of in vitro experiments using adult human dermal fibroblasts (HDFs) as well as a human monocytic cell line (THP-1) were devised to gain further insight into the benefits of the different formulations of commercially available HA products injected into the dermis for the prevention and treatment of skin ageing. The objective of this study was to assess three commercially available hyaluronic acid (HA) products with similar therapeutic aims but varying concentrations and molecular weights. The evaluation aimed to quantify the stimulation of adult HDFs and the inflammatory response in THP-1 monocytes. The results showed that hyaluronic acid of 0.9% concentration and (2700-3400k) Da has shown that it has the ability to biostimulate fibroblasts to secrete elastin, thus improving their morphology, as well as enhancing their regenerative capacity in response to mechanical aggression. On the other hand, it was observed that it also has a greater anti-inflammatory property than HAs of other molecular weights and different concentrations, as evidenced by IL-8 and IL-6 determinations in THP-1 monocyte cultures. In conclusion, the in vitro studies showed that VHMWHA can stimulate adult dermal fibroblasts.