Inhibition Potential of Cycloartane-Type Glycosides from the Roots of Cimicifuga dahurica against Soluble Epoxide Hydrolase

Phytochemistry and ethnopharmacological studies of genus Cimicifuga: A systematic and comprehensive review

ETHNOPHARMACOLOGICAL USES

Black cohosh, also known as Cimicifuga sp., is one of the most widely used ethnomedicine for the treatment of major health issues in women. Some reports show that Cimicifuga sp. exhibit anti-cancer, anti-viral, anti-microbial, anti-pyretic, and anti-inflammatory properties.

PURPOSE OF THIS REVIEW

The objective of this comprehensive review is to furnish current and exhaustive knowledge pertaining to the pharmacological, phytochemical, and therapeutic properties of Cimicifuga sp.

MATERIALS AND METHODS

In this review, all the available information was collected on Cimicifugasp. via computerized search using Google Scholar, PubMed, Research Gate, Sci-Hub, supplementary resources (books, government reports, and Ph.D. theses).

RESULT

The phytochemical investigation on Cimicifuga sp. has shown phytoconstituents such as triterpenoid glycosides, phenylpropanoid, flavonoids, saponin, lignan, nitrogenous compounds, alkaloids, 4α-Methyl steroids and some other component like monoterpene lactones cimicifugolides A-C etc. Cimicifuga conveys a wide scope of research on in-vitro and in-vivo pharmacological potential, like anti-cancer, anti-microbial, anti-viral, anti-inflammatory, estrogenic, anti-oxidant, anti-neoplastic, anti-depressant, anti-Alzheimer, and anti-climacteric properties.

CONCLUSION

This article discusses the medicinal and traditional histories of various Cimicifuga species. Because quality control and safety assessments of Cimicifuga species are currently lacking, only a limited portion of the plant may be used as medication. The majority of current research focuses on triterpene glycosides. Although there are a variety of additional molecules that may have novel biological functions, systematic investigations of these compounds are lacking. The Cimicifuga plant has to go through a lot of studies before it can be completely used in clinics as a viable medicinal contender.

Isocucurbic Acid Derivatives and Soluble Epoxide Hydroxylase Inhibitors from the Flowers of Chrysanthemum indicum L

Soluble epoxide hydrolase (sEH) inhibitory activity guided fractionation and isolation of two new isocucurbic acid derivatives (1 and 2) and nine known compounds (3-11) from the flowers of Chrysanthemum indicum L. Their structures were elucidated on the basis of spectroscopic data interpretation and comparison with those reported in previous studies. Luteolin (3), acacetin-7-O-β-D-glucopyranoside (6), and methyl 3,4-di-O-caffeoylquinate (10) displayed sEH inhibitory activities with IC50 values ranging from 13.7±3.6 to 20.8±0.4 μM. Enzyme kinetic analysis revealed that 3, 6, and 10 were non-competitive inhibitors with Ki values of 14.8±0.5, 31.2±0.8, and 3.9±0.2 μM, respectively. Additionally, molecular docking studies indicated compound 10 had the ability to form six hydrogen bonds at sEH active site, resulting binding energy as low as -9.58 Kcal/mol.

Systematically identifying the anti-inflammatory constituents of Cimicifuga dahurica by UPLC-Q/TOF-MS combined with network pharmacology analysis

Cimicifuga dahurica (Turcz.) Maxim, which is also regarded as the main origin of "Shengma" in the Chinese Pharmacopoeia, has been used as a cooling and detoxification agent for thousands of years. Our previous phytochemical investigations of C. dahurica extracts (CDEs) led to the isolation of a series of 9,19-cycloalkane triterpenoids and phenolic acids showing a potential anti-inflammatory activity. However, the chemical profiling of CDEs and the material basis of its anti-inflammatory effect in vivo has not been clarified. In the present study, the CDE chemical profile and prototype components in rat plasma were identified via ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. As a result, a total of 106 components were identified or tentatively characterized in CDEs, including 54 triterpenoids, 35 phenolic acids, eight amides and nine other type constituents (39 compounds were confirmed with the reference standards). In addition, 20 prototype components (15 triterpenoids and five phenolic acids) were identified in rat plasma, which potentially related to the anti-inflammatory effects of CDEs. Moreover, the anti-inflammatory activities of the main prototype components were further evaluated by their inhibitory effects on the production of NO, as well as the expressions of iNOS and COX-2 in lipopolysaccharide-stimulated RAW264.7 cells, which indicated that 9,19-cycloalkane triterpenoids may play an anti-inflammatory role by down-regulating the expression of iNOS.

3'-O-Acetyl-24-Epi-7,8-Didehydrocimigenol-3-O-β-DXylopryranoside Decreases Amyloid Beta Production in Amyloid Precursor Protein-Transfected HeLa Cells

Extracellular beta amyloid (Aβ) plaques are the neuropathological hallmarks of Alzheimer’s disease (AD). Accordingly, reducing Aβ levels is considered a promising strategy for AD prevention. 3’-O-acetyl-24-epi-7,8-didehydrocimigenol-3-O-β-D-xylopryranoside significantly decreased the Aβ production and this effect was accompanied with reduced sAPPβ production known as a soluble ectodomain APP fragment through β-secretases in HeLa cells overexpressing amyloid precursor proteins (APPs). This compound also increased the level of sAPPα, which is a proteolytic fragment of APP by α-secretases. In addition, 3’-O-acetyl-24-epi-7,8-didehydrocimigenol-3-O-β-D-xylopryranoside decreased the protein level of β-secretases, but the protein levels of A disintegrin and metalloproteinase (ADAM) family, especially ADAM10 and ADAM17, are increased. Thus, 3’-O-acetyl-24-epi-7,8-didehydrocimigenol-3-O-β-D-xylopryranoside could be useful in the development of AD treatment in the aspect of amyloid pathology.

Discovery of Soluble Epoxide Hydrolase Inhibitors from Chemical Synthesis and Natural Products

Soluble epoxide hydrolase (sEH) is an α/β hydrolase fold protein and widely distributed in numerous organs including the liver, kidney, and brain. The inhibition of sEH can effectively maintain endogenous epoxyeicosatrienoic acids (EETs) levels and reduce dihydroxyeicosatrienoic acids (DHETs) levels, resulting in therapeutic potentials for cardiovascular, central nervous system, and metabolic diseases. Therefore, since the beginning of this century, the development of sEH inhibitors is a hot research topic. A variety of potent sEH inhibitors have been developed by chemical synthesis or isolated from natural sources. In this review, we mainly summarized the interconnected aspects of sEH with cardiovascular, central nervous system, and metabolic diseases and then focus on representative inhibitors, which would provide some useful guidance for the future development of potential sEH inhibitors.

Two new chemical constituents from the rhizomes of Actaea dahurica

A new phenylpropanoid allopyranoside (1) and a new indolinone alkaloid (2) were isolated from the rhizomes of Actaea dahurica (syn. Cimicifuga dahurica). The structures of those two compounds were deduced as cimicifugaside F (1) and 3E,11E-(3-methyl-2-butenylidene acid)-2-indolinone-1-O-β-d-glucopyranoside (2) by detailed analysis of their MS, 1D and 2D NMR data and comparison with literatures. Additionally, the isolates were evaluated for their inhibitory effects on the production of NO by LPS-stimulated RAW 264.7 macrophages.

Two new triterpenoid-chromone hybrids from the rhizomes of Actaea cimicifuga L. (syn. Cimicifuga foetida L.) and their cytotoxic activities

Two new triterpenoid-chromone hybrids, cimitriteromones H (1) and I (2), along with two known analogues (3, 4) were isolated from the phytochemical research on the n-butyl alcohol extracts of Actaea cimicifuga rhizomes. The new compounds were elucidated by spectroscopic experiments and chemical method. The cytotoxic activities of the isolated compounds were tested on A-549/Taxol cell line. Cimitriteromone I (2) showed cytotoxicity with IC₅₀ value of 27.14 ± 1.38 μM comparable to positive control group cisplatin (IC₅₀ value of 25.80 ± 1.15 μM).

Epoxy Fatty Acids: From Salt Regulation to Kidney and Cardiovascular Therapeutics: 2019 Lewis K. Dahl Memorial Lecture

Epoxyeicosatrienoic acids (EETs) are epoxy fatty acids that have biological actions that are essential for maintaining water and electrolyte homeostasis. An inability to increase EETs in response to a high-salt diet results in salt-sensitive hypertension. Vasodilation, inhibition of epithelial sodium channel, and inhibition of inflammation are the major EET actions that are beneficial to the heart, resistance arteries, and kidneys. Genetic and pharmacological means to elevate EETs demonstrated antihypertensive, anti-inflammatory, and organ protective actions. Therapeutic approaches to increase EETs were then developed for cardiovascular diseases. sEH (soluble epoxide hydrolase) inhibitors were developed and progressed to clinical trials for hypertension, diabetes mellitus, and other diseases. EET analogs were another therapeutic approach taken and these drugs are entering the early phases of clinical development. Even with the promise for these therapeutic approaches, there are still several challenges, unexplored areas, and opportunities for epoxy fatty acids.

Unraveling Plant Natural Chemical Diversity for Drug Discovery Purposes

The screening and testing of extracts against a variety of pharmacological targets in order to benefit from the immense natural chemical diversity is a concern in many laboratories worldwide. And several successes have been recorded in finding new actives in natural products, some of which have become new drugs or new sources of inspiration for drugs. But in view of the vast amount of research on the subject, it is surprising that not more drug candidates were found. In our view, it is fundamental to reflect upon the approaches of such drug discovery programs and the technical processes that are used, along with their inherent difficulties and biases. Based on an extensive survey of recent publications, we discuss the origin and the variety of natural chemical diversity as well as the strategies to having the potential to embrace this diversity. It seemed to us that some of the difficulties of the area could be related with the technical approaches that are used, so the present review begins with synthetizing some of the more used discovery strategies, exemplifying some key points, in order to address some of their limitations. It appears that one of the challenges of natural product-based drug discovery programs should be an easier access to renewable sources of plant-derived products. Maximizing the use of the data together with the exploration of chemical diversity while working on reasonable supply of natural product-based entities could be a way to answer this challenge. We suggested alternative ways to access and explore part of this chemical diversity with in vitro cultures. We also reinforced how important it was organizing and making available this worldwide knowledge in an "inventory" of natural products and their sources. And finally, we focused on strategies based on synthetic biology and syntheses that allow reaching industrial scale supply. Approaches based on the opportunities lying in untapped natural plant chemical diversity are also considered.

Protective Effects of Compounds from Cimicifuga dahurica against Amyloid Beta Production in Vitro and Scopolamine-Induced Memory Impairment in Vivo

Cimicifuga dahurica has traditionally been used as an antipyretic, analgesic, and anti-inflammatory agent and as a treatment for uterine and anal prolapse. This study has investigated the potential beneficial effects of this medicinal plant and its components on Alzheimer's disease (AD) with a focus on amyloid beta (Aβ) production and scopolamine-induced memory impairment in mice. An ethanol extract from C. dahurica roots decreased Aβ production in APP-CHO cells [Chinese hamster ovarian (CHO) cells stably expressing amyloid precursor protein (APP)], as determined by an enzyme-linked immunosorbent assay and Western blot analysis. Then, the compounds isolated from C. dahurica were tested for their antiamyloidogenic activities. Four compounds (1-4) efficiently interrupted Aβ generation by suppressing the level of β-secretase in APP-CHO cells. Moreover, the in vivo experimental results demonstrated that compound 4 improved the cognitive performances of mice with scopolamine-induced disruption on behavioral tests and the expression of memory-related proteins. Taken together, these results suggest that C. dahurica and its constituents are potential agents for preventing or alleviating the symptoms of AD.

Anti-inflammatory secondary metabolites from the stems of Millettia dielsiana Harms ex Diels

A phytochemical investigation for the constituents of the stems of Millettia dielsiana Harms ex Diels resulted in the isolation of a new isoflavone glycoside, mildiside A (1), and 14 known compounds (2-15). Their chemical structures were determined using a combination of IR, NMR, MS, and optical rotation analysis, as well as comparison with the literature data. The ethanolic (EtOH) extract and several isolated compounds exert the inflammatory effect of nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophage cells.

Bioactive triterpene glycosides from the fruit of Stauntonia hexaphylla and insights into the molecular mechanism of its inflammatory effects

Chromatography of the ethanol extract of the medicinal fruit Stauntonia hexaphylla resulted in the purification of 26 compounds (1-26), including two undescribed triterpene saponins 1 and 2 (hexaphylosides A and B). Their structures were confirmed by spectroscopic data, including IR, HR QTOF MS, ¹H, ¹³C NMR, COSY, HMQC, HMBC, and TOCSY, and HPLC sugar analysis after acid hydrolysis. The anti-inflammatory effects of the high-purity constituents (1-26) on lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells were investigated by screening nitric oxide production. The NO inhibitory activity of compounds 6 and 10 with the IC₅₀ values of 1.33 and 1.10 µM, respectively. The structure-activity relationships (SAR) of the isolated compounds were also analyzed. Furthermore, compounds 6 and 10 inhibited the protein expression inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 via Western blotting analysis. This showed that compounds 6 and 10 contributed to the anti-inflammatory effects of S. hexaphylla fruit, which could be developed as a natural nutraceutical and functional food ingredient.

Cytotoxic 9,19-cycloartane type triterpenoid glycosides from the roots of Actaea dahurica

Ten undescribed 9,19-cycloartane type triterpenoid glycosides (cimdahxynoside A-J) and five known analogues were obtained from the phytochemical research on the roots of Actaea dahurica (syn. Cimicifuga dahurica). All compounds were characterised by spectroscopic experiments, chemical method and X-ray Single-crystal diffraction analysis. Cimdahxynoside A represented the first X-ray crystallography of 9,19-cycloartane type triterpenoid diglycoside. The cytotoxicity of all compounds were tested against five human cancer cell lines. Cimdahxynoside F showed significant cytotoxicity, with IC₅₀ values between 6.6 and 9.9 μM.

The insight of in vitro and in silico studies on cholinesterase inhibitors from the roots of Cimicifuga dahurica (Turcz.) Maxim

Cholinesterases (ChEs) are enzymes that break down neurotransmitters associated with cognitive function and memory. We isolated cinnamic acids (1 and 2), indolinones (3 and 4), and cycloartane triterpenoid derivatives (5-19) from the roots of Cimicifuga dahurica (Turcz.) Maxim. by chromatography. These compounds were evaluated for their inhibitory activity toward ChEs. Compound 1 was determined to have an IC50 value of 16.7 ± 1.9 μM, and to act as a competitive inhibitor of acetylcholinesterase (AChE). Compounds 3, 4 and 14 were found to be noncompetitive with IC50 values of 13.8 ± 1.5 and 6.5 ± 2.5 μM, and competitive with an IC50 value of 22.6 ± 0.4 μM, respectively, against butyrylcholinesterase (BuChE). Our molecular simulation suggested each key amino acid, Tyr337 of AChE and Asn228 of BuChE, which were corresponded with potential inhibitors 1, and 3 and 4, respectively. Compounds 1 and 4 were revealed to be promising compounds for inhibition of AChEs and BuChEs, respectively.

Ganolearic Acid A, a Hexanorlanostane Triterpenoid with a 3/5/6/5-Fused Tetracyclic Skeleton from Ganoderma cochlear

Ganolearic acid A (1), a 3,4- seco-hexanortriterpenoid featuring a rare 3/5/6/5 tetracyclic system, was obtained in trace amounts from Ganoderma cochlear by a LC-UV/MS-guided method. Meanwhile, a new 3,4- seco-nortriterpenoid, fornicatin M (2), as well as its biogenetic precursor, fornicatin D (3), was isolated. The stereochemical structure of 1 was completely established by 1D, 2D NMR, IR, and HRMS spectra, as well as ¹³C NMR and electronic circular dichroism calculations. The plausible biogenetic pathway of 1 and 2 was proposed. Furthermore, their anti-inflammatory activities were evaluated.

Survey of natural products reported by Asian research groups in 2017

The new natural products reported in 2017 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2017 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.

Yunnanterpene G, a spiro-triterpene from the roots of Cimicifuga foetida, downregulates the expression of CD147 and MMPs in PMA differentiated THP-1 cells

A new cycloartane triterpene, yunnanterpene G (1), containing an oxaspiro[5.4]decane moiety, was purified from the roots of Cimicifuga foetida. The new structure was determined from spectroscopic data and the X-ray diffraction method. Biological evaluations revealed that compound 1 significantly inhibited the mRNA expression of the atherosclerosis-related adhesion molecule CD147 (extracellular matrix metalloproteinase inducer, EMMPRIN), and proteolytic enzymes matrix metalloproteinase 2 (MMP-2), MMP-9 and MMP-14, in a dose-dependent manner in phorbol-12-myristate-13-acetate-induced human monocytic THP-1 cells by quantitative real-time PCR method. At the same time, the migration ability of the induced THP-1 cells was potently inhibited. Furthermore, western blot experiments showed that compound 1 at 25 μM strongly suppressed phosphorylation of NF-κB p65 and p38 MAPK in the differentiated THP-1 cells.

Yunnanterpene G (1), a new cycloartane triterpene with an oxaspiro[5.4]decane moiety, was purified from the roots of Cimicifuga foetida. Significantly, it downregulates the expression of CD147 and MMPs in PMA differentiated THP-1 cells.