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.

Background: 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.

Objectives: To evaluate the antioxidant, anti-inflammatory, anti-apoptotic, and proliferative effects of combined LLLT and guarana extract therapy on human dermal fibroblasts.

Methods: 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/cm ) 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.

Results: 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.

Conclusions: Our results suggest that concomitant treatment with guarana and LLLT may promote fibroblast biostimulation and thus is clinically relevant.