Interaction between low-level laser therapy and Guarana (Paullinia cupana) extract induces antioxidant, anti-inflammatory, and anti-apoptotic effects and promotes proliferation in dermal fibroblasts.

Low-level laser therapy (LLLT) has several clinical applications; however, its benefits are not universal. Therefore, combination therapy with LLLT and extracts from the guarana (Paullinia cupana) plant may improve its effectiveness as guarana extracts exhibit anti-aging properties.To evaluate the antioxidant, anti-inflammatory, anti-apoptotic, and proliferative effects of combined LLLT and guarana extract therapy on human dermal fibroblasts.

Human dermal fibroblasts (HFF-1) were cultured and initially exposed to several concentrations (1, 3, 5, 10, 30 µg/mL) of guarana extract. The experimental concentration of guarana extract was selected by analyzing cytokine levels, DNA oxidation, and apoptotic markers in LLLT-exposed (4 J/cm² ) and LLLT-unexposed fibroblast cultures. After 72 hours, the cells were analyzed using spectrophotometric, fluorimetric, immunological, and gene expression (qRT-PCR) assays. Flow cytometry was used to evaluate the effect of each treatment on cell cycle.

Fibroblasts treated with guarana (5 µg/mL) exhibited anti-inflammatory and anti-apoptotic properties been used in complementary protocols. Combined guarana and LLLT treatment significantly decreased protein carbonylation, lipoperoxidation, and DNA oxidation, downregulated the mRNA and protein expression of pro-inflammatory molecules, and upregulated IL-10 gene and protein expression. Guarana plus LLLT also decreased the levels of caspases 1, 3, and 8, increased the percentage of S-phase cells, and decreased FGF-1 and KGF-1 levels. Some of these changes were also observed after treatment with guarana or LLLT alone.Our results suggest that concomitant treatment with guarana and LLLT may promote fibroblast biostimulation and thus is clinically relevant.