Table 3: Influence of St. John’s Wort polysaccharides on cell physiology of keratinocytes (NEHK and HaCaT). Results were normalized to the untreated cells calculated as 0%. Proliferation was determined by BrdU incorporation ELISA. MTT reduction assay was performed to investigate the intracellular enzyme activity. The cytotoxicity was determined by calculating the extracellular LDH activity compared to total LDH activity according to the manufacturer instructions. Apoptosis was measured by flow cytometry using Annexin V and 7-AAD.

Polysaccharide fractionProliferation rate (NHEK)Intracellular enzyme activity (NHEK)Amount of necrotic cells (NHEK)Amount of apoptotic cells (HaCaT)

Hp116%  ±  817%  ±  70%13%  ±  11
Hp216%  ±  923%  ±  74%15%  ±  10
Hp3−17%  ±  821%  ±  108%21%  ±  9
Hp410%  ±  713%  ±  65%6%  ±  3