Antifungal activity of CHE-23C, a dimeric sesquiterpene from Chloranthus henryi

Terpenoids of plants from Chloranthaceae family: chemistry, bioactivity, and synthesis

Covering: 1976 to December 2023Chloranthaceae is comprised of four extant genera (Chloranthus, Sarcandra, Hedyosmum, and Ascarina), totaling about 80 species, many of which have been widely used as herbal medicines for diverse medical purposes. Chloranthaceae plants represent a rich source of structurally interesting and diverse secondary metabolites, with sesquiterpenoids and diterpenoids being the predominant structural types. Lindenane sesquiterpenoids and their oligomers, chemotaxonomical markers of the family Chloranthaceae, have shown a wide spectrum of bioactivities, attracting significant attention from organic chemists and pharmacologists. Recent achievements also demonstrated the research value of two unique structural types in this plant family, sesquiterpenoid-monoterpenoid heterodimers and meroterpenoids. This review systematically summarizes 682 structurally characterized terpenoids from 22 Chloranthaceae plants and their key biological activities as well as the chemical synthesis of selected terpenoids.

Chemistry and bioactivity of lindenane sesquiterpenoids and their oligomers

Covering: 1925 to July 2023Among the sesquiterpenoids with rich structural diversity and potential bioactivities, lindenane sesquiterpenoids (LSs) possess a characteristic cis, trans-3,5,6-carbocyclic skeleton and mainly exist as monomers and diverse oligomers in plants from the Lindera genus and Chloranthaceae family. Since the first identification of lindeneol from Lindera strychnifolia in 1925, 354 natural LSs and their oligomers with anti-inflammatory, antitumor, and anti-infective activities have been discovered. Structurally, two-thirds of LSs exist as oligomers with interesting skeletons through diverse polymeric patterns, especially Diels-Alder [4 + 2] cycloaddition. Fascinated by their diverse bioactivities and intriguing polycyclic architectures, synthetic chemists have engaged in the total synthesis of natural LSs in recent decades. In this review, the research achievements related to LSs from 1925 to July of 2023 are systematically and comprehensively summarized, focusing on the classification of their structures, chemical synthesis, and bioactivities, which will be helpful for further research on LSs and their oligomers.

Lindenane sesquiterpenoid dimers from Chloranthus holostegius with anti-neuroinflammatory activities in BV-2 microglia

Fifteen undescribed lindenane-type sesquiterpenoid dimers, designated chloranholides F-T (1-15), together with twenty-five known analogs (16-40), were isolated from the whole plants of Chloranthus holostegius. The isolate structures were elucidated by analysis of spectroscopic data and chemical methods, and their absolute configurations were determined by X-ray crystallography and electronic circular dichroism spectra. In anti-neuroinflammatory assays, all isolates were evaluated by examination of their inhibitory effect on nitric oxide (NO) in LPS-stimulated BV-2 cells, and the results showed that 21-24, 26, 30, 32 and 36 significantly inhibited the production of the inflammatory mediator NO, with IC50 values ranging from 3.18 to 11.46 μM, which was better than that of quercetin. Structure-activity relationship analysis revealed that two essential functional groups played an indispensable role in the anti-inflammatory effects. Moreover, 22 and 24 inhibited the LPS-induced upregulation of iNOS and COX-2 enzymes in BV-2 microglia at the protein level.

Flavokawain A suppresses the vasculogenic mimicry of HCC by inhibiting CXCL12 mediated EMT

BACKGROUND

Hepatocellular carcinoma has high ability of vascular invasion and metastasis. Vasculogenic mimicry (VM) is closely related to the metastasis and recurrence of hepatocellular carcinoma (HCC). According to previous research, Chloranthus henryi has anti-tumor effect, but its molecular mechanism in the treatment of HCC has not yet been stated.

PURPOSE

In our study, we aimed to investigate the effect of the extract of Chloranthus henryi in HCC and its target and molecular mechanism. We hoped to explore potential drugs for HCC treatment.

STUDY DESIGN/METHODS

In this study, we isolated a chalcone compound from Chloranthus henryi, compound 4, identified as flavokawain A (FKA). We determined the anti-HCC effect of FKA by MTT and identified the target of FKA by molecular docking and CETSA. Hepatoma cells proliferation, migration, invasion, and VM formation were examined using EDU, wound healing, transwell, vasculogenic mimicry, and IF. WB, RT-PCR, and cell transfection were used to explore the mechanism of FKA on hepatoma cells. Tissue section staining is mainly used to demonstrate the effect of FKA on HCC in vivo.

RESULTS

We confirmed that FKA can directly interact with CXCL12 and HCC proliferation, migration, invasion, and VM formation were all inhibited through reversing the EMT progress in vitro and in vivo through the PI3K/Akt/NF-κB signaling pathway. Additionally, by overexpressing and knocking down CXCL12, we got the same results.

CONCLUSION

FKA attenuated proliferation, invasion and metastatic and reversed EMT in HCC via PI3K/Akt/HIF-1α/NF-κB/Twist1 pathway by targeting CXCL12. This study proposed that FKA may be a candidate drug and prospective strategy for HCC therapy.

Targeting activator protein 1 signaling pathway by bioactive natural agents: Possible therapeutic strategy for cancer prevention and intervention

Activator protein 1 (AP-1) is a key transcription factor in the control of several cellular processes responsible for cell survival proliferation and differentiation. Dysfunctional AP-1 expression and activity are involved in several severe diseases, especially inflammatory disorders and cancer. Therefore, targeting AP-1 has recently emerged as an attractive therapeutic strategy for cancer prevention and therapy. This review summarizes our current understanding of AP-1 biology and function as well as explores and discusses several natural bioactive compounds modulating AP-1-associated signaling pathways for cancer prevention and intervention. Current limitations, challenges, and future directions of research are also critically discussed.

Shizukaol B, an active sesquiterpene from Chloranthus henryi, attenuates LPS-induced inflammatory responses in BV2 microglial cells

The objective of the current study was to evaluate the anti-inflammatory effects of shizukaol B, a lindenane-type dimeric sesquiterpene isolated from the whole plant of Chloranthus henryi, on lipopolysaccharide (LPS)-induced activation of BV2 microglial cells in vitro. Our data showed that shizukaol B concentration-dependently suppressed expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in LPS-stimulated BV2 microglia. Meanwhile, shizukaol B concentration- and time-dependently inhibited LPS-mediated c-Jun N-terminal kinase 1/2 (JNK) activation, but had little effect on extracellular signal-regulated kinase 1/2 or p38 phosphorylation. Furthermore, shizukaol B significantly blocked LPS-induced activator protein-1 (AP-1) activation, evidenced by reduced phosphorylation and nuclear translocation of c-Jun and DNA binding activity of AP-1. Taken together, our findings suggest that shizukaol B exerts anti-inflammatory effects in LPS-activated microglia partly by modulating JNK-AP-1 signaling pathway.

Constituents from Chloranthaceae plants and their biological activities

The Chloranthaceae is a small family with only four genera (

Bioactive ent-Pimarane and ent-Abietane Diterpenoids from the Whole Plants of Chloranthus henryi

Two new ent-pimarane (1 and 2), eight new ent-abietane (3-10) diterpenoids, and eight known analogues (11-18) were isolated from the whole plants of Chloranthus henryi. The absolute configuration of 1 was determined on the basis of single-crystal X-ray diffraction data. Compound 8 represents a class of rare naturally occurring C-14 norabietanes, and compounds 9 and 10 feature rare 13,14-seco-abietane skeletons. Compounds 5, 12, 13, and 15 inhibited the yeast-to-hyphae transition of Candida albicans with IC50 values between 97.3 and 738.7 μM.

Antioxidant and Anti-Inflammatory Activities of a Natural Compound, Shizukahenriol, through Nrf2 Activation

Imbalance in the antioxidant defense system leads to detrimental consequences, such as neurological disorders. The Nrf2 signaling is known as a main pathway involved in cellular defense system. Nrf2 is a transcription factor that regulates oxidative stress response by inducing expression of various antioxidant enzyme genes. In this study, we screened several pure natural compounds for Nrf2 activator. Among them, shizukahenriol (SZH), isolated from Chloranthus henryi, activated Nrf2, and induced expression of the Nrf2-dependent antioxidant enzymes HO-1, GCLC, and GCLM in BV-2 microglial cells. This natural compound was also effective in suppressing production of inflammatory molecules NO, TNF-α, and inhibition of NF-κB p65 translocation to the nucleus in a dose-dependent manner. We also examined whether SZH rescued the microglial cells from oxidative stress-induced cell death. Pretreatment with SZH dose-dependently attenuated H₂O₂-induced cytotoxicity in BV-2 microglial cells. These results suggested SZH as a potential neuroprotective agent for neurological disorders.

Phytochemical and biological studies of Chloranthus medicinal plants

The plants of genus Chloranthus have been investigated in many chemical and pharmacological laboratories due to their complex secondary metabolites and diverse bioactivities. The aim of this review is to provide an up-to-date overview on the chemistry and bioactivity of the compounds isolated, mainly sesquiterpenoids and diterpenoids, from the genus Chloranthus over the past few decades.

Sesquiterpenoids from Chloranthus multistachys

An 8,9-seco-lindenane disesquiterpenoid, chloramultiol G, four eudesmane sesquiterpenoids, ent-(3R)-3-hydroxyatractylenolide III and multistalactones A-C, and four guaiane sesquiterpenoids, (1R,4S,5R,8S,10S)-zedoalactone A and multistalactones D-F, along with 14 known compounds, were isolated from whole plant tissues of Chloranthus multistachys. Their structures were established by extensive NMR experiments in conjunction with mass spectrometry. Except for chloramultiol G, the absolute stereochemistries of the other eight were confirmed by single-crystal X-ray crystallography and CD spectra. Nine compounds were tested for cytotoxicity against five human tumor cell lines and for antifungal activity against four microorganisms in vitro, but all were inactive.

Chloramultiols A-F, lindenane-type sesquiterpenoid dimers from Chloranthus multistachys

Six new highly complex lindenane-type sesquiterpenoid dimers, chloramultiols A-F (1-6), along with six known analogues, were isolated from the whole plant of Chloranthus multistachys. The structures of 1-6 were elucidated on the basis of mass spectrometry (MS) and 1D and 2D NMR spectroscopic analysis. Among them, compounds 1 and 6 contain a unique 18-membered macrocyclic triester ring. All compounds isolated were evaluated for the inhibition of the growth of five tumor cell lines.