Hyperforin is a phytochemical produced by some of the members of the plant genus Hypericum, notably Hypericum perforatum (St John's wort).[2] Hyperforin may be involved in the pharmacological effects of St. John's wort,[2] specifically in its antidepressant effects.[3][4][5]Meta-analyses of clinical trials suggest that H. perforatum is as effective as SSRIs for treating mild to moderate depression and is better tolerated, although findings are limited by short study durations.
Hyperforin is found in significant amounts only in H. perforatum, where it accumulates as a probable plant defense compound, with modern carbon dioxide extraction methods used to isolate it from mixtures containing related compounds like adhyperforin.
Occurrence
Hyperforin has only been found in significant amounts in Hypericum perforatum with other related species such as Hypericum calycinum containing lower levels of the phytochemical.[2] It accumulates in oil glands, pistils, and fruits, probably as a plant defensive compound.[6] The first natural extractions were done with ethanol and afforded a 7:1 yield of crude extract to phytochemical however, this technique produced a mixture of hyperforin and adhyperforin.[3][7][8] The extraction technique has since been modernized using lipophilic liquid CO2 extraction to afford a 3:1 crude to phytochemical extraction which is then further purified away from adhyperforin.[3][7][8] This CO2 extraction is rather tricky still because typical 'supercritical' conditions extract less material whereas anything over 40 °C (100 °F) will degrade hyperforin.[3][7][8] Other Hypericum species contain low amounts of hyperforin.[9]
Chemistry
Hyperforin is a prenylatedphloroglucinol derivative and is a member of the Polycyclic polyprenylated acylphloroglucinol family, also known as the PPAP family. Hyperforin is a unique PPAP because it consists of a C8 quaternary stereocenter which was a synthetic challenge unlike other PPAP synthetic targets.[3][4][10] The structure of hyperforin was elucidated by a research group from the Shemyakin Institute of Bio-organic Chemistry (USSR Academy of Sciences in Moscow) and published in 1975.[11][12] A total synthesis of the non-natural hyperforin enantiomer was reported in 2010 which required approximately 50 synthetic transformations.[13] In 2010, an enantioselective total synthesis of the correct enantiomer was disclosed. The retrosynthetic analysis was inspired by hyperforin's structural symmetry and biosynthetic pathway. The synthetic route undertaken generated a prostereogenic intermediate which then established the synthetically challenging C8 stereocenter and facilitated the stereochemical outcomes for the remainder of the synthesis.[10]
Hyperforin is unstable in the presence of light and oxygen.[14] Frequent oxidized forms contain a C3 to C9 hemiketal/heterocyclic bridge or will form furan/pyran derivatives.[7][8]
Pharmacokinetics
Some pharmacokinetic data on hyperforin is available for an extract containing 5% hyperforin. Maximal plasma levels (Cmax) in human volunteers were reached 3–4 hours after administration of an extract containing 14.8 mg hyperforin. Biological half-life (t1/2) and mean residence time were 9 hours and 12 hours, respectively, with an estimated steady state plasma concentration of 100 ng/mL (approx. 180 nM) for 3 doses per day. Linear plasma concentrations were observed within a normal dosage range and no accumulation occurred.[15]
In healthy male volunteers, 612 mg dry extract of St. John's wort produced hyperforin pharmacokinetics characterized by a half-life of 19.64 hours.[16]
Current research focuses on understanding the biosynthesis of hyperforin and applying advanced techniques like omics, genome editing, and synthetic biology to enhance their pharmaceutical and medical uses.[21]
It faces production challenges that biotechnological methods, such as specialized plant root cultures and microbial biosynthesis, are being developed to overcome for scalable and modifiable manufacturing.[3]
Natural and semi-synthetic analogues of Hyperforin
Two meta-analyses of preliminary clinical trials evaluating the efficacy of St. John's wort for treating mild-to-moderate depression indicated a response similar to selective serotonin reuptake inhibitors and with better tolerance, although the long-term generalization of study results was limited by the short duration (4–12 weeks) of reviewed studies.[22][23]
^ abcd"Hyperforin". PubChem, US National Library of Medicine. 8 September 2018. Retrieved 13 September 2018.
^ abcdefGaid M, Biedermann E, Füller J, Haas P, Behrends S, Krull R, et al. (May 2018). "Biotechnological production of hyperforin for pharmaceutical formulation". European Journal of Pharmaceutics and Biopharmaceutics. 126: 10–26. doi:10.1016/j.ejpb.2017.03.024. PMID28377273. S2CID4701643.
^ abcdVajs V, Vugdelija S, Trifunović S, Karadzić I, Juranić N, Macura S, Milosavljević S (July 2003). "Further degradation product of hyperforin from Hypericum perforatum (St John's Wort)". Fitoterapia. 74 (5): 439–444. doi:10.1016/S0367-326X(03)00114-X. PMID12837358.
^ abcdVerotta L, Appendino G, Belloro E, Jakupovic J, Bombardelli E (May 1999). "Furohyperforin, a prenylated phloroglucinol from st. John's wort (Hypericumperforatum)". Journal of Natural Products. 62 (5): 770–772. Bibcode:1999JNAtP..62..770V. doi:10.1021/np980470v. PMID10346967.
^Smelcerovic A, Spiteller M (March 2006). "Phytochemical analysis of nine Hypericum L. species from Serbia and the F.Y.R. Macedonia". Die Pharmazie. 61 (3): 251–252. PMID16599273.
^Bystrov NS, Gupta S, Dobrynin VN, Kolosov MN, Chernov BK (January 1976). "[Structure of the antibiotic hyperforin]". Doklady Akademii Nauk SSSR (in Russian). 226 (1): 88–90. PMID1248360.
^Liu F, Pan C, Drumm P, Ang CY (February 2005). "Liquid chromatography-mass spectrometry studies of St. John's wort methanol extraction: active constituents and their transformation". Journal of Pharmaceutical and Biomedical Analysis. 37 (2): 303–312. doi:10.1016/j.jpba.2004.10.034. PMID15708671.
^Biber A, Fischer H, Römer A, Chatterjee SS (June 1998). "Oral bioavailability of hyperforin from hypericum extracts in rats and human volunteers". Pharmacopsychiatry. 31 (Suppl 1): 36–43. doi:10.1055/s-2007-979344. PMID9684946. S2CID24700980.
^Schulz HU, Schürer M, Bässler D, Weiser D (2005). "Investigation of the bioavailability of hypericin, pseudohypericin, hyperforin and the flavonoids quercetin and isorhamnetin following single and multiple oral dosing of a hypericum extract containing tablet". Arzneimittel-Forschung. 55 (1): 15–22. doi:10.1055/s-0031-1296820. PMID15727160. S2CID6880438.
^Newall CA, Barnes J, Anderson LR (2002). Herbal medicines: a guide for healthcare professionals. London: Pharmaceutical Press. ISBN978-0-85369-474-8.
^ abChatterjee SS, Bhattacharya SK, Wonnemann M, Singer A, Müller WE (1998). "Hyperforin as a possible antidepressant component of hypericum extracts". Life Sciences. 63 (6): 499–510. doi:10.1016/S0024-3205(98)00299-9. PMID9718074.
^Ng QX, Venkatanarayanan N, Ho CY (March 2017). "Clinical use of Hypericum perforatum (St John's wort) in depression: A meta-analysis". Journal of Affective Disorders. 210: 211–221. doi:10.1016/j.jad.2016.12.048. PMID28064110. 27 clinical trials with a total of 3808 patients were reviewed [...] For patients with mild-to-moderate depression, St John's wort has comparable efficacy and safety when compared to SSRIs. Follow-up studies carried out over a longer duration should be planned to ascertain its benefits.
