Isolation and Structure of Cancer Cell Growth Inhibitory Tetracyclic Triterpenoids from the Zimbabwean Monadenium lugardae

Unveiling the pharmacological potential of plant triterpenoids in breast cancer management: an updated review

Breast cancer is the most prevalent type of cancer, the fifth leading cause of cancer-related deaths, and the second leading cause of cancer deaths among women globally. Recent research has provided increasing support for the significance of phytochemicals, both dietary and non-dietary, particularly triterpenoids, in the mitigation and management of breast cancer. Recent studies showed that triterpenoids are promising agents in the treatment and inhibition of breast cancer achieved through the implementation of several molecular modes of action on breast cancer cells. This review discusses recent innovations in plant triterpenoids and their underlying mechanisms of action in combating breast cancer within the timeframe spanning from 2017 to 2023. The present work is an overview of different plant triterpenoids with significant inhibition on proliferation, migration, apoptosis resistance, tumor angiogenesis, or metastasis in various breast cancer cells. The anticancer impact of triterpenoids may be attributed to their antiproliferative activity interfering with angiogenesis and differentiation, regulation of apoptosis, DNA polymerase inhibition, change in signal transductions, and impeding metastasis. The present review focuses on several targets, mechanisms, and pathways associated with pentacyclic triterpenoids, which are responsible for their anticancer effects. We could conclude that natural triterpenoids are considered promising agents to conquer breast cancer.

Triterpenoids, steroids and other constituents from Euphorbia kansui and their anti-inflammatory and anti-tumor properties

Six undescribed triterpenoids (euphokanols A-F), two undescribed C21-steroidal glycosides (euphokanosides A and B), together with fifty-four known compounds were isolated from the roots of Euphorbia kansui. Their structures were demonstrated by extensive spectroscopic data (1D, 2D NMR and HR-ESI-MS), and the absolute configuration of euphokanol A was elucidated based on electronic circular dichroism (ECD) calculation. Among them, euphokanol A was a tetracyclic triterpenoid with a 5,10-epoxy moiety and concurrent rearrangement of Me-19(10 → 9) and Me-30 (14 → 8), while euphokanols B and C were rare 19(10 → 9) abeo-tirucallane-type triterpenoids with Δ5(10) double bonds and 7,8-epoxy moieties. In addition, ten C21-steroidal glycosides were isolated from Euphorbia plants for the first time. Moreover, cynotophylloside B, caudatin, 5α,8α-epidioxy-22E-ergosta-6,22-diene-3β-ol, 6β,7β-epoxy-3β,4β,5β-trihydroxyl-20-deoxyingenol, 13-hydroxyingenol-3-(2,3- dimethylbutanoate)-13-dodecanoate, ingenol, 3-O-benzoyl-13-O-dodecanoateingenol, 3-O-(2'E,4'Z-decadienoyl)-20-O-acetylingenol, 20-O-acetylingenol and 20- deoxyingenol exhibited significant inhibition on NO production with IC50 values of 9.10, 17.38, 1.71, 0.55, 0.57, 12.22, 0.56, 0.30, 11.21 and 2.98 μM, respectively. Furthermore, wilfoside KIN, cynsaccatol L, kanesulone A, and 3β,7β,15β-triacetyloxy-5α-benzoyloxy-2α,8α-dihydroxyjatropha-6(17),11E-diene-9, 14-dione showed cytotoxicity against HepG2 cell line, with IC50 values of 12.55, 12.61, 18.24 and 18.26 μM, respectively. 13-Hydroxyingenol-3-(2,3-dimethylbutanoate)-13- dodecanoate exhibited anti-proliferation activity on MCF-7 cell line with an IC50 value of 17.12 μM. Specifically, euphol selectively inhibited the growth of human glioma stem cells (GSC-3# and GSC-12#), with IC50 values of 8.89 and 13.00 μM, respectively.

Toward the Asymmetric de Novo Synthesis of Lanostanes: Construction of 7,11-Dideoxy-Δ5-lucidadone H

Efforts to establish an asymmetric entry to hexanorlanostanes has resulted in a concise synthesis of 7,11-dideoxy-Δ5-lucidadone H from epichlorohydrin. By exploiting metallacycle-mediated annulative cross-coupling (to establish a functionalized hydrindane) and stereoselective formation of the steroidal C9-C10 bond to establish a stereodefined 9-alkyl estrane, 14 subsequent steps have been established to generate a hexanorlanostane system. Key transformations include formal inversion of the C13 quaternary center, oxidative dearomatization/group-selective Wagner-Meerwein rearrangement, and Lewis acid mediated semi-Pinacol rearrangement.

Cucurbitane triterpenoid entities derived from Hemsleya penxianensis triggered glioma cell apoptosis via ER stress and MAPK signalling cross-talk

In the present study, six new cucurbitane type compounds, including three triterpenoids hemsleyacins P-R (6-7, 13) and three cucurbitane-type triterpenoid glycosides hemsleyaosides L-N (15-17), along with seventeen known cucurbitacin analogues were separated from the root tuber of Hemsleya penxianensis and elucidated based on NMR and HRESIMS. Then, 23 analogues of three types, namely, polyhydroxy-type (I) (1-7), monohydroxy-type (II) (8-13), and glycosides-type (III) (14-23), were assessed for their antitumor activity and structure-activity relationship analysis (SAR). We determined temozolomide (TMZ)-resistant GBM cell was the most sensitive to the tested compounds, and found hemsleyaoside N (HDN) displayed the best antineoplastic potency. Furthermore, we confirmed the anti-glioma activity of HDN in patient-derived recurrent GBM strains, GBM organoid (GBO) and orthotopic nude mouse models. Investigations exploring the mechanism made clear that HDN induced synchronous activation of UPR and MAPK signaling, which triggered deadly ER stress and apoptosis. Taken together, the potent antitumor activity of HDN warrants further comprehensive evaluation as a novel anti-glioma agent.

Neritriterpenols A-G, euphane and tirucallane triterpenes from Euphorbia neriifolia L. and their bioactivity

Euphorbia neriifolia L. is widely distributed in India, Thailand, and China and has been used to treat diseases such as rotten sores and asthma as well as for its antidiabetic and anticancer effects. In this study, seven undescribed triterpenes, including six euphanes, neritriterpenols A-B and D-G, and a tirucallane, neritriterpenol C, together with four known triterpenes, were isolated from ethanolic extracts of E. neriifolia stems. Their structures with absolute configurations were determined through detailed spectroscopic data, including 1D and 2D NMR data analyses, single-crystal X-ray diffraction analysis, ECD spectra, and DP4+ NMR data calculations as well as Mo₂(OAc)₄-induced ECD analysis. Furthermore, preliminarily evaluation of the anti-inflammatory and anti-proliferative effects of the isolated triterpenes leads to the structure-activity relationship (SAR) studies implying that the unsaturated functional group at the end of the C17 side chain on euphane-type triterpenes may be correlated with the increase of anti-inflammatory and anti-proliferative activities.

Characteristics, chemical compositions and biological activities of propolis from Al-Bahah, Saudi Arabia

Propolis has been used to treat several diseases since ancient times, and is an important source of bioactive natural compounds and drug derivatives. These properties have kept the interest of investigators around the world, leading to the investigation of the chemical and biological properties and application of propolis. In this report, the chemical constituents that are responsible for the anticancer activities of propolis were analyzed. The propolis was sourced from Al-Baha in the southern part of the Kingdom of Saudi Arabia. Standard protocols for chemical fractionation and bioactivity-guided chemical analysis were used to identify the bio-active ethyl acetate fraction. The extraction was performed in methanol and then analyzed by gas chromatography-mass spectrometry (GC-MS). The major compounds are triterpenoids, with a relative concentration of 74.0%; steroids, with a relative concentration of 9.8%; and diterpenoids, with a relative concentration of 7.9%. The biological activity was characterized using different approaches and cell-based assays. Propolis was found to inhibit the proliferation of cancer cells in a concentration-dependent manner through apoptosis. Immunofluorescence staining with anti-α-tubulin antibodies and cell cycle analysis indicated that tubulin and/or microtubules are the cellular targets of the L-acetate fraction. This study demonstrates the importance of Saudi propolis as anti-cancer drug candidates.