Bruceine a

Bruceine a exerts antitumor effect against colon cancer by accumulating ROS and suppressing PI3K/Akt pathway

Bruceine A (BA), a quassic ester from bruceine javanica, regulates diverse intracellular signal transduction pathways and manifests a variety of biological activities, however, its pharmacological mechanism in treating colon cancer (CC) is unclear. In this study, we investigated the anticancer effects of BA on CC cells and the underlying mechanisms. The network pharmacology research indicated that Akt1 and Jun and PI3K/Akt pathways are the predominant targets and critical signaling pathways, respectively, for BA treatment of CC. Meanwhile, molecular docking results implied that BA could conjugate to pivotal proteins in the PI3K/Akt pathway. BA remarkably suppressed the proliferation of CC cells HCT116 and CT26 with 48-h IC50 of 26.12 and 229.26 nM, respectively, and the expression of p-PI3K/p-Akt was restrained by BA at the molecular level as verified by Western blot assay. Further mechanistic studies revealed BA impacted cell cycle-related proteins by regulating the expression of P27 (a protein bridging the PI3K/Akt signaling pathway with cycle-related proteins), arresting the cell cycle in the G2 phase, inhibiting the proliferation of HCT116 and CT26, and facilitated the apoptosis in CC cells by activating the mitochondria-associated apoptosis protein Bax and accumulating reactive oxygen species, in addition to BA apparently inhibited the migration of CC cells. Taken together, our results demonstrated that BA might be a promising chemotherapy drug in the treatment of CC.

A novel P38α MAPK activator Bruceine A exhibits potent anti-pancreatic cancer activity

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Bruceine A displays potent anti-pancreatic cancer activity in vitro and in vivo.

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Phosphoproteomic analyses identify bruceine A induces phosphorylation of p38α MAPK.

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Octet system and microscale thermophoresis reveal p38α MAPK has high affinity for bruceine A.

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Molecular simulations illustrate determinants of bruceine A binding with p38α MAPK.

Pancreatic cancer remains one of the cancers with the poorest prognosis bearing an overall 5-year survival rate of about 5%. Efficient new chemotherapic drugs are still highly desired. Here, bruceine A, a quassinoid identified from the dried fruits of Brucea javanica (L.) Merr., displayed the most potent anti-proliferation activity against pancreatic cancer in vitro and in vivo. Phosphoproteomic analysis revealed p38α MAPK phosphorylation was involved in bruceine A’s action in MIA PaCa-2 cells. Utilizing fortebio octet system and microscale thermophoresis, we found p38α MAPK had high affinity for bruceine A. Molecular docking and molecular dynamic simulations showed that bruceine A widely bound to residues (Leu171, Ala172, Met179, Thr180, Val183) in P-loop of p38α MAPK. Key determinants of bruceine A binding with P-loop of p38α MAPK were 19-C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]>O, 22-CH₃, 32-CH₃, and 34-CH₃. Taken together, our findings demonstrate that bruceine A binds directly to p38α MAPK, which can be used to probe the role of p38α MAPK phosphorylation in pancreatic cancer progression, and as a novel lead compound for pancreatic cancer therapy.

Development of Potential Antitumor Agents from the Scaffolds of Plant-Derived Terpenoid Lactones

Naturally occurring terpenoid lactones and their synthetic derivatives have attracted increasing interest for their promising antitumor activity and potential utilization in the discovery and design of new antitumor agents. In the present perspective article, selected plant-derived five-membered γ-lactones and six-membered δ-lactones that occur with terpenoid scaffolds are reviewed, with their structures, cancer cell line cytotoxicity and in vivo antitumor activity, structure-activity relationships, mechanism of action, and the potential for developing cancer chemotherapeutic agents discussed in each case. The compounds presented include artemisinin (ART, 1), parthenolide (PTL, 2), thapsigargin (TPG, 3), andrographolide (AGL, 4), ginkgolide B (GKL B, 5), jolkinolide B (JKL B, 6), nagilactone E (NGL E, 7), triptolide (TPL, 8), bruceantin (BRC, 9), dichapetalin A (DCT A, 10), and limonin (LMN, 11), and their naturally occurring analogues and synthetic derivatives. It is hoped that this contribution will be supportive of the future development of additional efficacious anticancer agents derived from natural products.

Brusatol isolated from Brucea javanica (L.) Merr. induces apoptotic death of insect cell lines

Brucea javanica (L.) Merr. is a medicine plant distributed widely throughout Asia where its bitter fruits have been used traditionally in medicine for treating various ailments and controlling some pests. In recent years, concerns over the potential impact of synthetic pesticides on human health and environment have now become more pressing to develop environmentally friendly pesticides. In this paper, brusatol, a quassinoid, was isolated from the fruit of B. javanica, and identified using X-ray crystallographic analysis. Results showed that brusatol has potent contact toxicity (LD50, 2.91 μg/larva, 72 h) and anfieedant activity (AFC50, 17.4 mg/L, 48 h) against the third-instar larvae of Spodoptera exigua. Brusatol demonstrated cytotoxic effects to the tested insect cell lines, IOZCAS-Spex-II and Sf21, in a time- and dose-dependent manner. After brusatol treatment, apoptotic cell death with the DNA fragmentation, activation of caspase-3 and release of cytochrome c was preliminarily observed in both IOZCAS-Spex-II and Sf21. These results indicated the existence of apoptotic death with the mitochondrial-dependent pathway induced by brusatol in Sf21 and IOZCAS-Spex-II cell lines. Our studies will provide important knowledge to understand mechanisms of action of brusatol and to develop brusatol and its derivatives as insecticides.

Brusatol

The title compound, C(26)H(32)O(11), is composed of an α,β-unsaturated cyclo-hexa-none ring (A), two cyclo-hexane rings (B and C), a six-membered lactone ring (D) and tetra-hydro-furan ring (E). Ring A exists in a half-chair conformation with a C atom displaced by 0.679 (2) Å from the mean plane through the remaining five atoms. Ring B exists in a normal chair conformation. Both rings C and D exist in a twisted-chair conformation due to the O-atom bridge and the carbonyl group in rings C and D, respectively. Ring E shows an envelope conformation with a C atom displaced by 0.761 (1) Å from the mean plane through the remaining five atoms. The ring junctions are A/B trans, B/C trans, C/D cis and D/E cis. An intra-molecular O-H⋯O hydrogen bond occurs. In the crystal, O-H⋯O hydrogen bonds involving the hy-droxy, lactone and ester groups and C-H⋯O inter-actions are observed.