The photophysics of hypericin have been studied in its complex with two different isoforms, A1-1 and P1-1, of the protein glutathione S-transferase (GST). One molecule of hypericin binds to each of the two GST subunits. Comparisons are made with our previous results for the hypericin/human serum albumin complex (Photochem. Photobiol. 1999, 69, 633-645). Hypericin binds with high affinity to the...

The acylated phloroglucinol, hyperforin, the main active ingredient of St. John's Wort, exerts antidepressant properties via indirect inhibition of serotonin reuptake by selectively activating the canonical transient receptor potential channel 6 (TRPC6). Hyperforin treatment can lead to drug-drug interactions due to potent activation of the nuclear receptor PXR (NR1I2), a key transcriptional re...

Hypericin is used as a powerful naturally occurring photosensitizer in photodynamic therapy (PDT). Activated by visible light, it kills tumour cells and tissues via generation of reactive oxygen species (ROS). Depending on the protocol, apoptotic cell death can be achieved very effectively by hypericin-PDT. To analyze the fundamental molecular mechanisms leading to apoptosis induced by photodam...

RAND researchers conducted a systematic review that synthesized evidence from randomized controlled trials of St. John's wort (SJW)-used adjunctively or as monotherapy-to provide estimates of its efficacy and safety in treating adults with major depressive disorder. Outcomes of interest included changes in depressive symptomatology, quality of life, and adverse effects. Efficacy meta-analyses u...

In vitro experiments in plastic receptacles are the basis of characterization of new photosensitizers (PSs) for the photodynamic therapy. We recently reported that lipophilic PSs adhere to cell culture microplates in a kinetic-like manner (Engelhardt et al., 2011). In the current study, we examined the interaction and phototoxic effects of the microplate-adhered PS in cancer cells. Therefore, w...

Cutaneous wound healing is accelerated by mechanical stretching, and treatment with hyperforin, a major component of a traditional herbal medicine and a known TRPC6 activator, further enhances the acceleration. We recently revealed that this was due to the enhancement of ATP-Ca2+ signaling in keratinocytes by hyperforin treatment. However, the low aqueous solubility and easy photodegradation im...

BACKGROUND One of the acquired biological hallmarks of tumor multistep development is the resistance of cancer cells to apoptosis; therefore, induction of apoptosis is an important therapeutic approach. Hypericum species are spread throughout the world and have been investigated for their biological properties. OBJECTIVES Our previous studies had demonstrated cytotoxicity of Hypericum scabrum...

Glucose-dependent energy required for glioma metabolism depends on hexokinase, which is mainly bound to mitochondria. A decrease in intracellular pH leads to a release of hexokinase-binding, which in turn decreases glucose phosphorylation, ATP content, and cell proliferation. Thus, intracellular pH might be a target for therapy of gliomas, and a search for agents able to modulate intracellular ...