Bioassay and UPLC-Q-Orbitrap-MS/MS guided isolation of polycyclic polyprenylated acylphloroglucinols from St. John's wort and their neuroprotective activity

Hypertums A-J, bioactive polycyclic polyprenylated acylphloroglucinols with diverse skeletons from Hypericum perforatum L. (St. John's wort)

Ten previously undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs), hypertums A-J (1-10), together with eighteen known analogues (11-28), belonging to five subclasses of PPAPs, were isolated from the aerial parts of Hypericum perforatum L. (St. John's wort). The chemical structures and the absolute configurations of these compounds were elucidated by comprehensive analysis of NMR spectra, HR-ESI-MS data, quantum chemical calculations, chemical transformation, and X-ray crystallography. The carbon skeletons of compounds 1-5 were first characterized from H. perforatum. Compounds 6 and 7 were rare congeners assembled with two different polyprenylated acylphloroglucinol moieties through an ester bond. The plausible biosynthetic pathways for 1-10 were postulated. Compound 3, yezo'otogirin A (27) and yezo'otogirin B (28) exhibited weak acetylcholinesterase inhibitory activities at 50 μM. The isolated PPAPs were also evaluated for their anti-neuroinflammatory activity. Compound 3 inhibited nitric oxide (NO) production in LPS-stimulated BV-2 microglial cells with IC50 value of 34.34 μM and also suppressed the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, anti-neuroinflammatory effect of 3 was also supported in zebrafish model.

Neuroprotective Effect of Nor-Prenylated Acylphloroglucinols from Hypericum perforatum L. (St John's Wort) in the MPTP-Induced Zebrafish Model

Hypericum perforatum L. (St John's wort) has been widely studied and used for antidepressant treatment, as well as, rarely, featuring in studies on its chemical composition for Parkinson's disease (PD) treatment. Five new nor-prenylated acylphloroglucinols with a cyclohexanone core, norperforatums A-E (1-5), together with four known analogs [(2R,3R,4S,6R)-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)cyclohexanone (6), hyperscabrin B (7), (2R,3R,4S,6R)-6-methoxycarbonyl-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)cyclohexanone (8), and hyperscabin K (9)], were isolated from the aerial parts of H. perforatum. The structures and absolute configurations of the new compounds were characterized by multiple spectroscopic means, including nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), ultraviolet visible absorption spectroscopy (UV), infrared spectroscopy (IR), calculated electronic circular dichroism (ECD) data, and X-ray signal crystal diffraction. In addition, the efficacy of these isolations was evaluated against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD in zebrafish larvae. Compound 9 had the best therapeutic effect, by significantly increasing the total distance traveled and the mean speed of movement in PD dyskinesia zebrafish larvae. Moreover, it enhanced superoxide dismutase (SOD) activity and inhibited reactive oxygen species (ROS) production in a dose-dependent manner. These results suggest that compound 9 may have ameliorative effects on PD symptoms by inhibiting oxidative stress. This study provides new insights into the treatment of H. perforatum for PD.

Determination of natural populations to be included in breeding program in St. John's wort species (Hypericum perforatum L.)

St. John's wort (Hypericum perforatum L.) is a medicinal and aromatic plant of rapidly increasing importance. The cultural production of this species, which is of economic importance due to its medicinal properties, is limited. One of the main ways to increase production is to develop cultivars. Thus, the homogeneous raw material required for a standard product will be provided. This study aimed to determine the characteristics of natural populations to obtain productive cultivars with high hypericin and hyperforin that can meet market demands. In addition to yield and quality values, other characteristic features of the plant such as flower diameter, petal length and petal width, which directly affect productivity, were revealed in the study. The study was conducted under field conditions for two years with three replications. Fresh flower weight among the populations varied between 30.15 and 240.28 g/plant, while the hypericin ratio varied between 51.32 and 105.31 (mg/100 g). The study determined a wide variation among the populations, and the populations with superior characteristics were included in the breeding program.

Spirohypertones A and B as potent antipsoriatics: Tumor necrosis factor-α inhibitors with unprecedented chemical architectures

Tumor necrosis factor-α (TNF-α) is a promising target for inflammatory and autoimmune diseases. Spirohypertones A (1) and B (2), two unprecedented polycyclic polyprenylated acylphloroglucinols with highly rearranged skeletons, were isolated from Hypericum patulum. The structures of 1 and 2 were confirmed through comprehensive spectroscopic analysis, single-crystal X-ray diffraction and electronic circular dichroism calculations. Importantly, 2 showed remarkable TNF-α inhibitory activity, which could protect L929 cells from death induced by co-incubation with TNF-α and actinomycin D. It also demonstrated the ability to suppress the inflammatory response in HaCaT cells stimulated with TNF-α. Notably, in an imiquimod-induced psoriasis murine model, 2 restrained symptoms of epidermal hyperplasia associated with psoriasis, presenting anti-inflammatory and antiproliferative effects. This discovery positions 2 as a potent TNF-α inhibitor, providing a promising lead compound for developing an antipsoriatic agent.

Four new compounds from fruits of Hypericum patulum Thunb

A new naphthoquinone, patulumnaphthoquinone A (1) and three new glycosides, patulumside B (2), patulumside C (3) and patulumside D (4) were isolated from the 30% ethanol extract of the fresh ripe fruits of Hypericum patulum Thunb. using column chromatography techniques. The structures of these compounds including absolute configurations were elucidated on the basis of HRESIMS, NMR spectroscopic analyses, calculated electronic circular dichroism spectra and comparison with the literatures.

Four New Polyprenylated Acylphloroglucinols from Hypericum perforatum L

Hyperforatums A-D (1-4), four new polyprenylated acylphloroglucinols, together with 13 known compounds were isolated and identified from the aerial parts of Hypericum perforatum L. (St. John's wort). Their structures were confirmed with a comprehensive analysis comprising spectroscopic methods, including 1D and 2D NMR, HRESIMS, and electronic circular dichroism (ECD) calculations. Hyperforatum A featured an unusual chromene-1,4-dione bicyclic system, and hyperforatums B and C were two rare monocyclic PPAPs with five-membered furanone cores. Compound 1 exhibited a moderate inhibition effect on NO production in BV-2 microglial cells stimulated by LPS.

UPLC-Q-Orbitrap-MS/MS-Guided Isolation of Bioactive Withanolides from the Fruits of Physalis angulata

Physalis angulata Linn. is an exotic Amazonian fruit that is commonly recognized as wild tomato, winter cherry, and gooseberry. While its fruit is known to contain many nutrients, such as minerals, fibers, and vitamins, few papers have investigated withanolide derivatives from its fruits. UPLC-Q-Orbitrap-MS/MS, which produces fragmentation spectra, was applied for the first time to guide the isolation of bioactive withanolide derivatives from P. angulata fruits. As a result, twenty-six withanolide derivatives, including two novel 1,10-secowithanolides (1 and 2) and a new derivative (3), were obtained. Compounds 1 and 2 are rare rearranged 1,10-secowithanolides with a tetracyclic 7/6/6/5 ring system. All structures were assigned through various spectroscopic data and quantum chemical calculations. Nine withanolide derivatives exhibited significant inhibitory effects on three tumor cell lines with IC50 values of 0.51-13.79 μM. Moreover, three new compounds (1-3) exhibited potential nitric oxide inhibitory effects in lipopolysaccharide-stimulated RAW264.7 cells (IC50: 7.51-61.8 μM). This investigation indicated that fruits of P. angulata could be applied to treat and prevent cancer and inflammatory-related diseases due to their potent active withanolide derivatives.