Jolkinolide B: A comprehensive review of its physicochemical properties, analytical methods, synthesis and pharmacological activity

Highly oxygenated ent-abietane diterpenoid lactones from Euphorbia peplus and their anti-inflammatory activity

Eleven new ent-abietane diterpenoid lactones, designated euphjatrophanes H-R (1-11), were isolated from the whole plants of Euphorbia peplus, along with nine previously identified congeners (12-20). Their structures, including absolute configurations, were elucidated through a combination of NMR, HRESIMS, single-crystal X-ray diffraction, and calculations of ECD and DP4 + technologies. Notably, the absolute configurations of six compounds 1, 2, 4, 5, 6, and 7 were unambiguously determined by single-crystal X-ray diffraction analyses, conducted with Cu Kα radiation. The anti-inflammatory potential of all ent-abietane diterpenoid lactones was evaluated on macrophages. Compounds 6-9, 12-16 and 19 significantly suppressed nitric oxide production, while 10 μM of compounds 6, 9, 11 and 16 remarkably suppressed the mRNA expression of IL-6, IL-1β, and TNFα in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Notably, compound 6 demonstrated a dose-dependent inhibition of the levels of inflammatory mediators (IL-6, IL-1β, and TNFα). Furthermore, compound 6 effectively suppressed FOXO1 expression and reduced the phosphorylation level of NF-κB p65. These findings suggest that compound 6 might be a promising candidate for treating inflammation-related diseases.

Bioactive abietenolide diterpenes from Suregada procera

The phytochemical investigation of the leaves and the roots of Suregada procera afforded the new ent-abietane diterpenoid sureproceriolide A (1) along with the known secondary metabolites 8,14β:11,12α-diepoxy-13(15)-abietane-16,12-olid (2), jolkinolide A (3), jolkinolide E (4), ent-pimara-8(14),15-dien-19-oic acid (5), sitosterol (6), oleana-9(11):12-dien-3β-ol (7), and oleic acid (8). Their structures were elucidated by NMR spectroscopic and mass spectrometric analyses, and the structure of jolkinolide A (3) was confirmed by single-crystal X-ray diffraction analysis. Sureproceriolide A (1) showed modest activity against the Gram-positive bacterium Staphylococcus lugdunensis (MIC = 31.44 μM), and sitosterol (6) against the Gram-negative bacterium Porphyromonas gingivalis (IC50 = 45.37 μM). Jolkinolide A (3) and E (4) as well as sitosterol (6) inhibited the release of NOS (IMR-90 cells), TNF-α (HaCaT cells) and NF-κB (HaCaT cells), with IC50 values of 0.43, 3.21, and 10.32 μM, respectively. Compound 6 showed antitumoral activity against SK-MEL-28 (IC50 = 20.66 μM) and CCD-13Lu (IC50 = 24.70 μM) cell lines, with no cytotoxic effect against the prostate cells PrEC (CC50 > 300 μM).

Jolkinolide B attenuates allergic airway inflammation and airway remodeling in asthmatic mice

Asthma is a widely prevalent chronic disease that brings great suffering to patients and may result in death if it turns severe. Jolkinolide B (JB) is one diterpenoid component separated from the dried roots of Euphorbia fischeriana Steud (Euphorbiaceae), and has anti--inflammatory, antioxidative, and antitumor properties. However, the detailed regulatory role and associated regulatory mechanism in the progression of asthma remain elusive. In this work, it was demonstrated that the extensive infiltration of bronchial inflammatory cells and the thickening of airway wall were observed in ovalbumin (OVA)-induced mice, but these impacts were reversed by JB (10 mg/kg) treatment, indicating that JB relieved the provocative symptoms in OVA-induced asthma mice. In addition, JB can control OVA-triggered lung function and pulmonary resistance. Moreover, JB attenuated OVA-evoked inflammation by lowering the levels of interleukin (IL)-4, IL-5, and IL-13. Besides, the activated nuclear factor kappa B (NF-κB) and transforming growth factor-beta-mothers against decapentaplegic homolog 3 (TGFβ/smad3) pathways in OVA-induced mice are rescued by JB treatment. In conclusion, it was disclosed that JB reduced allergic airway inflammation and airway remodeling in asthmatic mice by modulating the NF-κB and TGFβ/smad3 pathways. This work could offer new opinions on JB for lessening progression of asthma.

Jolkinolide B inhibits the progression of hepatocellular carcinoma by regulating Musashi-2 protein

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths. However, the HCC treatment is still challenging. Herein, we aimed to reveal the anti-tumor effect of Jolkinolide B in HCC cell lines Huh-7 and SK-Hep-1. The results showed that Jolkinolide B inhibited the migration, invasion, and epithelial-to-mesenchymal transition(EMT) of HCC cells. In addition, Jolkinolide B induced HCC cell apoptosis by upregulating Bax and downregulating BCL-2 expressions. Furthermore, we demonstrated that Jolkinolide B inactivated the β-catenin signaling and reduced Musashi-2 expression. Finally, we revealed that Musashi-2 overexpression reversed the Jolkinolide B-induced anti-HCC effect. Overall, we proved that Jolkinolide B is a potential candidate for treating HCC.

Jolkinolide B ameliorates rheumatoid arthritis by regulating the JAK2/STAT3 signaling pathway

BACKGROUND

Jolkinolide B (JB), an ent‑abietane-type diterpenoid in Euphorbia plants, has various pharmacological activities, including anticancer, anti-inflammatory, and anti-tuberculosis activities. However, no previous studies have proven whether JB can be regarded as a targeted drug for the treatment of rheumatoid arthritis (RA).

PURPOSE

This study aimed to evaluate the anti-RA effects of JB and explore the potential mechanisms.

METHODS

Components and targets of JB and RA were identified in different databases, and potential targets and pathways were predicted by protein-protein interaction (PPI) network analysis and pathway enrichment analysis. Then, molecular docking and surface-plasmon resonance (SPR) were used to confirm the predict. The anti-arthritic effects of JB were studied in vivo with collagen-induced arthritis (CIA) rat model and in vitro with lipopolysaccharide (LPS) and interleukin-6 (IL-6)-induced RAW264.7 macrophage. Potential mechanisms were further verified by in vivo and in vitro experiments.

RESULTS

The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that Th17 cell differentiation, prolactin signaling pathway, and JAK/STAT signaling pathway might be associated with anti-RA effects of JB. Molecular docking and SPR results showed that JB bound effectively to JAK2. JB significantly decreased body weight loss, arthritis index, paw thickness, and synovial thickness in CIA rats. Histomorphological results suggested the protective effects of JB on CIA rats with ankle joint injury. Molecular biology analysis indicated that JB suppressed the mRNA expression of inflammatory factors in ankle joints for CIA rats and reduced the concentration of these factors in LPS- induced RAW264.7 macrophage. The protein expression level of the JAK2/STAT3 pathway was also significantly decreased by JB.

CONCLUSION

JB had a novel inhibitory effect on inflammation and bone destruction in CIA rats, and the mechanism might be related to the JAK2/STAT3 signaling pathway.

Asymmetric total synthesis and anti-hepatocellular carcinoma profile of enantiopure euphopilolide and jolkinolide E

A flexible asymmetric synthesis of both enantiomers of euphopilolide (1) and jolkinolide E (2) [(+)-and (-)-1, (+)-and (-)-2] has been accomplished. This synthesis features an intramolecular oxa-Pauson-Khand reaction (o-PKR) to expeditiously construct the challenging tetracyclic [6.6.6.5] abietane-type diterpene framework, elegantly showcasing the complexity-generating features of o-PKR synthetic methodology leveraging on a judiciously chosen suitable chiral pool scaffold. Furthermore, the anti-hepatocellular carcinoma (HCC) activity of synthetic (-)-euphopilolide (1), (-)-jolkinolide E (2) and their analogues was evaluated. We found that (-)-euphopilolide (1) and (-)-jolkinolide E (2) inhibited the proliferation and induced apoptosis in HCC cells. These findings lay a good foundation for further pharmacology studies of abietane lactone derivatives and provide valuable insight for the development of anti-HCC small molecule drug of natural product origin.