Herbal preparation extract for skin after radiotherapy treatment. Part One--Preclinical tests

Naran R is a herbal composition made of Plantago lanceolate folium, Malvae arboreae flos, Calendulae flos, Chamomillae inflorescentia, Lamii albi flos to prepare compresses or to wash skin with inflammations. The extract of this preparation is mixed to be applied as an ointment on patients' skin after radiotherapy. Experiments performed in vitro are part of pre-clinical tests with Naran R ointment. This study examined the impact of the plant composition for ethanol-water extract on human skin fibroblasts (HSF) culture. Samples of extract, prepared from patented amounts of herbs, were in the range of 25-225 μg/mL. Six methods were applied: standard spectrophotometric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, neutral red (NR) uptake assay, DPPH free radical scavenging test, labeling of cytoskeleton F-actin, staining of argyrophilic nucleolar organizer regions (AgNORs) and trypan blue coloration. The extract concentration 75 μg/mL was established as safe for application on human skin. In labeling of F-actin with rhodamine-phalloidin dye at this concentration the cytoskeleton was stable. The extract did not influence the membrane stability and had positive influence on the proliferation activity. It was confirmed in AgNOR test during incubation with extract, which led to formation of larger amount of smaller nucleolins. In DPPH scavenging activity test, the extract revealed over 8% higher free-radical scavenging activity in comparison to control. After trypan blue staining, the extract in concentration 125 μg/mL significantly lowered the cell viability. When the cytotoxic and anti-proliferative activity of the extracts were analyzed, MTT and Neutral Red (NR) methods were used. The cells' viability was maintained on a constant level (80-110%) after 24, 48 and 72 h of incubation. During all time of NR test (72 h) and even when 225 μg/mL of extract was applied, the viability of cells was in range 80-110% of control. Positive influence of the extract on investigated cells structure and proliferation, lack of toxicity and increasing anti-oxidant activity enable to consider this preparation as a natural remedy with potential application in skin therapy after radiation.