Typha latifolia L. fruit polysaccharides induce the differentiation and stimulate the proliferation of human keratinocytes in vitro

Ethnopharmacological relevanceIn Northern America Typha latifolia L. (Typhaceae) fruits are used for more than 4000 years for treatment of skin disorders, burns and as wound dressing to absorb the ichors.Aim of the studyThe following studies attempted to characterize water-soluble polysaccharides from aqueous Typha latifolia extracts and to investigate the influence of the polymers on cell physiology of human dermal fibroblasts (NHDF) and epidermal keratinocytes (NHEK).Materials and methodsWater-soluble raw polysaccharides (RPS) were isolated from Typha latifolia fruits and fractionated by anion exchange chromatography (AEC) and size exclusion chromatography (GPC). Fractions obtained were characterized concerning monosaccharide composition by HPAEC-PAD. The bioactivity of the polysaccharides was investigated on cell viability, proliferation, differentiation and gene expression NHDF of NHEK.ResultsRPS was fractionated into 5 heterodisperse fractions (TL1-TL5). The polysaccharides were composed mainly of glucose (more than 50% in RPS and TL4), galactose, xylose, mannose, glucuronic acid, galacturonic acid, arabinose, ribose, fucose, rhamnose, and fructose with differing amounts concerning to RPS and AEC-fractions. Proteins were detected in the RPS (10%) and to a less extend in TL1-TL3 (1-3%). TL1-TL3 significantly increased the proliferation of keratinocytes, whereas TL4 was shown to be a potent inductor of the early differentiation process of keratinocytes. Gene expression analysis supported these results since Smad3 and PKC-α, known to be part of signal pathways leading to cell differentiation, were significantly up regulated.Effects on fibroblasts were not observed, indicating cell specific activity of the polysaccharides.ConclusionThe results clearly indicate a rationale for the traditional use of Typha latifolia fruits extracts for wound healing to the strong stimulatory activity of the polysaccharides on keratinocytes proliferation and early differentiation, major activities necessary for potent wound-healing agents.

226Highlights► Typha latifolia fruits were used for skin treatment. ► We isolated and characterized the water-soluble polysaccharides and tested their bioactivity on human skin cells. ► Five heterodisperse polysaccharide fractions were obtained differing in their monosaccharide composition. ► Effects on fibroblasts were not observed but keratinocyte proliferation was increased by three fractions while the fraction with high beta-D-glucose content induced the differentiation.