Answers are grounded in this paper and cite their sources.
Comparative analysis confirms efficacy and safety of poly-L-lactic acid and hyaluronic acid injections in two patients, suggesting potential for combined treatment approaches.
Background. The mechanisms of skin aging are based on morphofunctional processes in the skin and underlying tissues that are influenced by genetic, hormonal, and environmental factors. Dermal fillers regulate skin cell metabolism and stimulate the synthesis of intracellular and extracellular components. Immunohistochemistry (IHC) demonstrates changes in biomarkers of skin aging and offers an objective assessment of skin remodeling processes following filler injections. Objective. To compare the efficacy and safety of poly-L-lactic acid (PLLA) and hyaluronic acid (HA) injections administered separately or in combination for the treatment of age-related skin changes. Material and methods. The present study included two patients who received injections of the investigational products into each of the three quadrants of the anterior abdominal wall. Prior to the injections and six weeks after the initial treatment, biopsy specimens were obtained from each quadrant for histological evaluation (hematoxylin and eosin staining, IHC). To improve the study’s reliability, a single-blind approach was used. Results. Immunohistochemical analysis revealed an upregulation of the dermal transforming growth factor beta-1 (TGF-β1) expression in both patients following administration of PLLA and HA, both separately and in combination. Upregulation in the receptor for hyaluronan-mediated motility (RHAMM) expression was observed in both study participants following HA administration and the combined application of PLLA and HA. Collagen fibrils hydration level, as determined by relative optical transmission coefficient of collagen, increased after the application of HA and the combination of PLLA and HA. The absence of adverse events following treatment with PLLA and HA, both as separate treatments and in combination, indicates a favorable safety profile for these products. Conclusion. The investigational products have been shown to be effective and safe. Synergistic effects were observed when PLLA and HA were administered in combination. The obtained results demonstrate significant potential for further investigation of combined methods for the treatment of age-related skin changes.
No takes yet. Share an insight, caveat, or question.
Timofeev et al. (2025) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: