Insecticidal Triterpenes in Meliaceae III: Plant Species, Molecules, and Activities in Munronia-Xylocarpus.

Plants of the Meliaceae family have long attracted researchers' interest due to their various insecticidal activities, with triterpenes being the main active ingredients. In this paper, we discuss 93 triterpenoids with insecticidal activity from 37 insecticidal plant species of 15 genera (Munronia, Neobeguea, Pseudocedrela, Nymania, Quivisia, Ruagea, Dysoxylum, Soymida, Lansium, Sandoricum, Walsura, Trichilia, Swietenia, Turraea, and Xylocarpus) in the family Meliaceae. Among these genera, Trichilia deserves further research, with twelve species possessing insecticidal activity. The 93 insecticidal molecules included 27 ring-seco limonoids (comprising 1 ring A-seco group chemical, 1 ring B-seco group chemical, 5 ring D-seco group chemicals, 14 rings A,B-seco group chemicals, 5 rings B,D-seco group chemicals, and 1 rings A,B,D-seco group chemical), 22 ring-intact limonoids (comprising 5 cedrelone-class chemicals, 6 trichilin-class chemicals, 7 havanensin-class chemicals, 2 azadirone-class chemicals, 1 vilasinin-class chemical, and 1 other chemical), 33 2,30-linkage chemicals (comprising 25 mexicanolide-class chemicals and 8 phragmalin-class chemicals), 3 1,n-linkage-group chemicals, 3 onoceranoid-type triterpenoids, 2 apotirucallane-type terpenoids, 2 kokosanolide-type tetranortriterpenoids, and 1 cycloartane triterpene. In particular, 59 molecules showed antifeedant activity, 30 molecules exhibited poisonous effects, and 9 molecules possessed growth regulatory activity. Particularly, khayasin, beddomei lactone, 3ß,24,25-trihydroxycycloartane, humilinolides A-E and methyl-2-hydroxy-3ß-isobutyroxy-1-oxomeliac-8(30)-enate showed excellent insecticidal activities, which were comparable to that of azadirachtin and thus deserved more attention. Moreover, it was noteworthy that various chemicals (such as 12α-diacetoxywalsuranolide, 11ß,12α-diacetoxycedrelone, 1α,7α,12α-triacetoxy-4α-carbomethoxy-11ß-hydroxy-14ß,15ß-epoxyhavanensin, and 11-epi-21-hydroxytoonacilide, etc.) from Turraea showed excellent insecticidal activity. Specially, the insecticidal activity of khayasin from Neobeguea against the coconut leaf beetle were similar to that of rotenone. Therefore, it was a promising candidate insecticide for the control of the coconut leaf beetle.

Isolation, Characterization, and Antiproliferative Activity of Terpenoids from the Tropical Plant Turraea delphinensis.

The isolation, structure determination, and biological evaluation of constituents from the organic extract of Turraea delphinensis Wahlert (Meliaceae) resulted in the isolation of 51 secondary metabolites, including 14 new terpenoids (six cycloartanes, four tirucallanes/euphanes, three limonoids, and a 7-keto sterol). Among the new compounds, 1 is the first triterpenoid with a trioxaspiro[4.4]nonane side chain, while 11-13 are the first 17-γ-lactone tetranortriterpenoids with four oxygenated functional groups at C-1, -3, -6, and -7. The isolated compounds were evaluated for antiproliferative activity against five human tumor cell lines, including a vinblastine-resistant cell line.

Immobilized cells on microcarriers for efficient and biomimetic screening of active compounds acting on FGFR4 from Fructus evodiae.

Cell membrane coating strategies have been increasingly researched in new drug discovery from complex herb extracts. However, these systems failed to maintain the functionality of the coated cells because cell membranes, not whole cells were used. Original source cells can be used as a vector for active compound screening in a manner that mimics in vivo processes. In this study, we established a novel approach to fabricate high-density fibroblast growth factor receptor 4 (FGFR4)-HEK293 cells on microcarriers covered with collagen through cell culture and covalent immobilization between proteins. This method enables the efficient screening of active compounds from herbs. Two compounds, evodiamine and limonin, were obtained from Fructus evodiae, which were proven to inhibit the FGFR4 target. Enhanced immobilization effects and negligible damage to FGFR4-HEK293 cells treated with paraformaldehyde were successfully confirmed by immunofluorescence assays and transmission electron microscopy. A column was prepared and used to analyze different compounds. The results showed that the method was selective, specific, and reproducible. Overall, the high density of cells immobilized on microcarriers achieved through cell culture and covalent immobilization represents a promising strategy for affinity screening. This approach highlights the potential of the affinity screening method to identify active compounds from an herbal matrix against designed targets and its prospects for use in drug discovery from herbs.

Lefamulin Overcomes Acquired Drug Resistance via Regulating Mitochondrial Homeostasis by Targeting ILF3 in Hepatocellular Carcinoma.

Acquired resistance represents a critical clinical challenge to molecular targeted therapies such as tyrosine kinase inhibitors (TKIs) treatment in hepatocellular carcinoma (HCC). Therefore, it is urgent to explore new mechanisms and therapeutics that can overcome or delay resistance. Here, a US Food and Drug Administration (FDA)-approved pleuromutilin antibiotic is identified that overcomes sorafenib resistance in HCC cell lines, cell line-derived xenograft (CDX) and hydrodynamic injection mouse models. It is demonstrated that lefamulin targets interleukin enhancer-binding factor 3 (ILF3) to increase the sorafenib susceptibility of HCC via impairing mitochondrial function. Mechanistically, lefamulin directly binds to the Alanine-99 site of ILF3 protein and interferes with acetyltransferase general control non-depressible 5 (GCN5) and CREB binding protein (CBP) mediated acetylation of Lysine-100 site, which disrupts the ILF3-mediated transcription of mitochondrial ribosomal protein L12 (MRPL12) and subsequent mitochondrial biogenesis. Clinical data further confirm that high ILF3 or MRPL12 expression is associated with poor survival and targeted therapy efficacy in HCC. Conclusively, this findings suggest that ILF3 is a potential therapeutic target for overcoming resistance to TKIs, and lefamulin may be a novel combination therapy strategy for HCC treatment with sorafenib and regorafenib.

Insights into Nimbolide molecular crosstalk and its anticancer properties.

Nimbolide, one of the main ingredients constituent of Azadirachta indica (neem) leaf extract, has garnered attention for its potential as an anticancer agent. Its efficacy against various cancers and chemopreventive action has been demonstrated through numerous in vivo and in vitro studies. This updated review aims to comprehensively explore the chemopreventive and anticancer properties of nimbolide, emphasizing its molecular mechanisms of action and potential therapeutic applications in oncology. The review synthesizes evidence from various studies that examine nimbolide's roles in apoptosis induction, anti-proliferation, cell death, metastasis inhibition, angiogenesis suppression, and modulation of carcinogen-metabolizing enzymes. Nimbolide exhibits multifaceted anticancer activities, including the modulation of multiple cell signaling pathways related to inflammation, invasion, survival, growth, metastasis, and angiogenesis. However, its pharmacological development is still in the early stages, mainly due to limited pharmacokinetic and comprehensive long-term toxicological studies. Nimbolide shows promising anticancer and chemopreventive properties, but there is need for systematic preclinical pharmacokinetic and toxicological research. Such studies are essential for establishing safe dosage ranges for first-in-human clinical trials and further advancing nimbolide's development as a therapeutic agent against various cancers. The review highlights the potential of nimbolide in cancer treatment and underscores the importance of rigorous preclinical evaluation to realize its full therapeutic potential.

Limonoids from the fruits of Chisocheton erythrocarpus and their mosquito larvicidal activities.

Phytochemical study of the fruits of Chisocheton erythrocarpus (Hiern) allowed the identification of eight undescribed limonoids, namely erythrocarpines O - V (1-6, 7a and 7b), along with seven known compounds. The structures of these compounds were elucidated based on spectroscopic and HRMS data, along with electronic circular dichroism to configure the absolute configuration. Erythrocarpines O and P are γ-hydroxybutenolide analogs of mexicanolide-type limonoids while erythrocarpine Q - V are phragmalin-type limonoids possessing a 1,29-oxymethylene bridge with either benzoyl or cinnamoyl moiety in their structures. Mosquito larvicidal activity revealed that crude DCM extract of C. erythrocarpus possessed a good larvicidal effect against Aedes aegypti larvae in 48 h (LC50 = 153.0 ppm). Subsequent larvicidal activity of isolated compounds indicated that erythrocarpine G (10) and 14-deoxyxyloccensin K (11) were responsible for the enhanced larvicidal effect of the extract, reporting LC50 values of 18.55 ppm and 41.16 ppm, respectively. Moreover, residual activity testing of the crude DCM extract revealed that the duration of its larvicidal effects is up to 14 days, where it maintained a 98 % larval mortality throughout the test period, under laboratory conditions.

Insights into the Mechanism of Action of the Degraded Limonoid Prieurianin.

Limonoids are extremely diversified in plants, with many categories of products bearing an intact, rearranged or fragmented oxygenated scaffold. A specific subgroup of fragmented or degraded limonoids derives from the tetranortriterpenoid prieurianin, initially isolated from the tree Trichilia prieuriana but also found in other plants of the Meliaceae family, including the more abundant species Aphanamixis polystachya. Prieurianin-type limonoids include about seventy compounds, among which are dregeanin and rohitukin. Prieurianin and analogs exhibit insecticidal, antimicrobial, antiadipogenic and/or antiparasitic properties but their mechanism of action remains ill-defined at present. Previous studies have shown that prieurianin, initially known as endosidin 1, stabilizes the actin cytoskeleton in plant and mammalian cells via the modulation of the architecture and dynamic of the actin network, most likely via interference with actin-binding proteins. A new mechanistic hypothesis is advanced here based on the recent discovery of the targeting of the chaperone protein Hsp47 by the fragmented limonoid fraxinellone. Molecular modeling suggested that prieurianin and, to a lesser extent dregeanin, can form very stable complexes with Hsp47 at the protein-collagen interface. Hsp-binding may account for the insecticidal action of the product. The present review draws up a new mechanistic portrait of prieurianin and provides an overview of the pharmacological properties of this atypical limonoid and its chemical family.

Computational Binding Study Hints at Ecdysone 20-Mono-Oxygenase as the Hitherto Unknown Target for Ring C-Seco Limonoid-Type Insecticides.

The insecticidal property of ring C-seco limonoids has been discovered empirically and the target protein identified, but, to date, the molecular mechanism of action has not been described at the atomic scale. We elucidate on computational grounds whether nine C-seco limonoids present sufficiently high affinity to bind specifically with the putative target enzyme of the insects (ecdysone 20-monooxygenase). To this end, 3D models of ligands and the receptor target were generated and their interaction energies estimated by docking simulations. As a proof of concept, the tetrahydro-isoquinolinyl propenamide derivative QHC is the reference ligand bound to aldosterone synthase in the complex with PDB entry 4ZGX. It served as the 3D template for target modeling via homology. QHC was successfully docked back to its crystal pose in a one-digit nanomolar range. The reported experimental binding affinities span over the nanomolar to lower micromolar range. All nine limonoids were found with strong affinities in the range of -9 < ΔG < -13 kcal/mol. The molt hormone ecdysone showed a comparable ΔG energy of -12 kcal/mol, whereas -11 kcal/mol was the back docking result for the liganded crystal 4ZGX. In conclusion, the nine C-seco limonoids were strong binders on theoretical grounds in an activity range between a ten-fold lower to a ten-fold higher concentration level than insecticide ecdysone with its known target receptor. The comparable or even stronger binding hints at ecdysone 20-monooxygenase as their target biomolecule. Our assumption, however, is in need of future experimental confirmation before conclusions with certainty can be drawn about the true molecular mechanism of action for the C-seco limonoids under scrutiny.

Codelivery of ivermectin and methyl dihydrojasmonate in nanostructured lipid carrier for synergistic antileukemia therapy.

Chronic myeloid leukemia is a life-threatening blood-cancer prevalent among children and adolescents. Research for innovative therapeutics combine drug-repurposing, phytotherapeutics and nanodrug-delivery. Ivermectin (Ivn) is a potent anthelmintic, repurposed for antileukemic-activity. However, Ivn exerts off-target toxicity. Methyl-dihydrojasmonate (MJ) is a phytochemical of known antileukemic potential. Herein, we developed for the first-time Ivn/MJ-coloaded nanostructured-lipid-carrier (Ivn@MJ-NLC) for leveraging the antileukemic-activity of the novel Ivn/MJ-combination while ameliorating possible adverse-effects. The developed Ivn@MJ-NLC possessed optimum-nanosize (97 ± 12.70 nm), PDI (0.33 ± 0.02), entrapment for Ivn (97.48 ± 1.48 %) and MJ (99.48 ± 0.57 %) and controlled-release of Ivn (83 % after 140 h) and MJ (80.98 ± 2.45 % after 48 h). In-vitro K562 studies verified Ivn@MJ-NLC prominent cytotoxicity (IC50 = 35.01 ± 2.23 µg/mL) with pronounced Ivn/MJ-synergism (combination-index = 0.59) at low-concentrations (5-10 µg/mL Ivn). Superior Ivn@MJ-NLC cytocompatibility was established on oral-epithelial-cells (OEC) with high OEC/K562 viability-ratio (1.49-1.85). The innovative Ivn@MJ-NLC enhanced K562-nuclear-fragmentation and afforded upregulation of caspase-3 and BAX (1.71 ± 0.07 and 1.45 ± 0.07-fold-increase, respectively) compared to control. Ex-vivo hemocompatibility and in-vivo-biocompatibility of parenteral-Ivn@MJ-NLC, compared to Ivn-solution, was verified via biochemical-blood analysis, histological and histomorphometric studies of liver and kidney tissues. Our findings highlight Ivn@MJ-NLC as an Ivn/MJ synergistic antileukemic platform, ameliorating possible adverse-effects.

Toonanoronoids A-E, five new limonoids from Toona ciliata var. yunnanensis.

Five new B-seco-limonoids, namely toonanoronoids A-E (1-5), in conjunction with three previously reported compounds, were isolated from the EtOAc extract of the twigs and leaves of Toona ciliata var. yunnanensis. Their structures were elucidated through comprehensive spectroscopic and X-ray crystallographic analysis. The cytotoxic activities of new compounds against five human tumor cell lines (HL-60, SMMC-7721, A549, MCF-7, and SW480) were screened, Compounds 4 and 5 exerted inhibition toward two tumor cell lines (HL-60, SW-480) with IC50 values between 1.7 and 5.9 µM.

Limonoids isolated from Chisocheton ceramicus Miq. and the antiadipogenic mechanism of action of ceramicine B.

Different types of limonoids have been isolated from plants of the Chisocheton genus, notably from the species Chisocheton ceramicus Miq. which is largely distributed in the Indonesian archipelago and Malaysia region. A variety of natural products have been found in the bark of the tree and characterized as antimicrobial and/or antiproliferative agents. The isolated limonoids include chisomicines A-E, proceranolide, and a few other compounds. A focus is made on a large series of limonoids designated ceramicines A to Z including derivatives with antiparasitic activities, antioxidant, antimelanogenic, and antiproliferative effects and/or acting as regulators of lipogenesis. The lead compound in the series is ceramicine B functioning as a potent inhibitor of lipid droplet accumulation (LDA). Extracts from Chisocheton ceramicus and ceramicines have shown anti-LDA effects, with little or no cytotoxic effects. Ceramicine B is the most active compound functioning as a regulator of lipid storage in cells and tissues. Ceramicine B is a transcriptional repressor of peroxisome proliferator-activated receptor γ (PPARγ) and an inhibitor of phosphorylation of the transcription factor FoxO1, acting via an upstream molecular target. Targeting of glycogen synthase kinase-3ß is proposed, based on the analogy with structurally related limonoids known to target this enzyme, and supported by a molecular docking analysis. The target and pathway implicated in ceramicine B activity are discussed. The analysis shed light on ceramicine B as a natural product precursor for the design of novel compounds capable of reducing LDA in cells and of potential interest for the treatment of obesity, liver diseases, and other pathologies.

Enhanced azadirachtin production in neem (Azadirachta indica) callus through NaCl elicitation: Insights into differential protein regulation via shotgun proteomics.

With their remarkable bioactivity and evolving commercial importance, plant secondary metabolites (PSMs) have gained significant research interest in recent years. Plant tissue culture serves as a credible tool to examine how abiotic stresses modulate the production of PSMs, enabling clear insights into plant stress responses and the prospects for controlled synthesis of bioactive compounds. Azadirachta indica, or neem has been recognized as a repository of secondary metabolites for centuries, particularly for the compound named azadirachtin, due to its bio-pesticidal and high antioxidant properties. Introducing salt stress as an elicitor makes it possible to enhance the synthesis of secondary metabolites, specifically azadirachtin. Thus, in this research, in vitro callus cultures of neem were micro-propagated and induced with salinity stress to explore their effects on the production of azadirachtin and identify potential proteins associated with salinity stress through comparative shotgun proteomics (LCMS/MS). To induce salinity stress, 2-month-old calli were subjected to various concentrations of NaCl (0.05-1.5%) for 4 weeks. The results showed that the callus cultures were able to adapt and survive in the salinity treatments, but displayed a reduction in fresh weight as the NaCl concentration increased. Notably, azadirachtin production was significantly enhanced in the salinity treatment compared to control, where 1.5% NaCl-treated calli produced the highest azadirachtin amount (10.847 ± 0.037 mg/g DW). The proteomics analysis showed that key proteins related to primary metabolism, such as defence, energy, cell structure, redox, transcriptional and photosynthesis, were predominantly differentially regulated (36 upregulated and 93 downregulated). While a few proteins were identified as being regulated in secondary metabolism, they were not directly involved in the synthesis of azadirachtin. In conjunction with azadirachtin elicitation, salinity stress treatment could therefore be successfully applied in commercial settings for the controlled synthesis of azadirachtin and other plant-based compounds. Further complementary omics approaches can be employed to enhance molecular-level modifications, to facilitate large-scale production of bioactive compounds in the future.

Alliaxylines A-E: five new mexicanolides from the stem barks of Dysoxylum alliaceum (Blume) Blume ex A.Juss.

A total of five new mexicanolides (1-5), namely alliaxylines A-E, together with two known limonoids 6 and 7, were isolated and identified from Dysoxylum alliaceum (Blume) Blume ex. A.Juss. (Meliaceae). The structures of these compounds were elucidated based on extensive spectroscopic analyses, including HR-ESI-MS, UV, IR, 1D, and 2D NMR, as well as theoretical stimulation of NMR shifts with the DP4 + algorithm. Consequently, this study aimed to examine cytotoxic activities of these compounds against MCF-7 and A549 cell lines. The results implied that compound 2 was the most potent against the two tested cells, with IC50 values of 34.95 ± 0.21 and 44.39 ± 1.03 µM.

Enhancement of hepatoprotective activity of limonin from citrus seeds against acetaminophen-induced liver injury by HSCCC purification and liposomal encapsulation.

Limonin is a natural tetracyclic triterpenoid compound in citrus seeds that presents hepatoprotective effects but is often discarded as agricultural waste because of its low content and low solubility. Herein, limonin with high purity (98.11%) from citrus seeds was obtained via purification by high-speed counter-current chromatography (HSCCC) and recrystallization. Limonin-loaded liposomes (Lip-LM) prepared by thin film hydration and high pressure homogenization method to enhance its solubility and hepatoprotective effect on APAP-induced liver injury (AILI). Lip-LM appeared as lipid nanoparticles under a transmission electron microscope, and showed well dispersed nano-scale size (69.04 ± 0.42 nm), high encapsulation efficiency (93.67% ± 2.51%), sustained release, fine stability. Lip-LM also exhibited significantly better hepatoprotective activity on AILI than free limonin in vivo. In summary, Lip-LM might be used as a potential hepatoprotective agent in the form of dietary supplement and provide an effective strategy to improve the potential value of citrus seeds.

Swieteliacates S-U, phragmalin limonoids, from the leaves of Swietenia macrophylla.

Three novel phragmalin-type limonoids, swieteliacates S-U (1-3), were isolated from Swietenia macrophylla leaves, alongside four previously identified limonoids (4-7). The structures, encompassing absolute configurations, were delineated through 1D and 2D NMR analyses, high-resolution mass spectrometry (HR-MS), and NMR and ECD calculations. Swieteliacate S (1) is a distinctive cryptate comprising a tricyclo[4.2.110,30.11,4]decane fragment and an additional five-membered oxygen ring. Compounds 3 and 5 exhibited inhibition rates of 26.08 ± 2.26% and 15.42 ± 3.66%, respectively, on triglyceride (TG) production in Hep G2 cells at 40 µM.

Limonin alleviates high-fat diet-induced dyslipidemia by regulating the intestinal barrier via the microbiota-related ILC3-IL22-IL22R pathway.

High-fat diet (HFD)-induced dyslipidemia is frequently accompanied by gut microbiota dysbiosis and a compromised gut barrier. Enhancing the intestinal barrier function emerges as a potential therapeutic approach for dyslipidemia. The ILC3-IL22-IL22R pathway, which responds to dietary and microbial signals, has not only attracted attention for its crucial role in maintaining the intestinal barrier, but recent reports have also suggested its potential in regulating lipid metabolism. Limonin is derived from the Chinese herb Evodiae fructus, which has shown potential in ameliorating dysbiosis of serum lipids. However, its underlying mechanisms remain elusive. Consequently, targeting the ILC3-IL22-IL22R pathway to enhance intestinal barrier function holds promise as a therapeutic approach for dyslipidemia. In this study, male C57BL/6 mice were subjected to a 16-week HFD to induce dyslipidemia and concurrently administered oral limonin. We discovered that limonin supplementation dramatically reduced serum lipid profiles in HFD-fed mice, significantly curbing HFD-induced weight gain and epididymal fat accumulation. Ileal histopathological evaluation indicated limonin's ameliorative effects on HFD-induced intestinal barrier impairment. Limonin also moderated the intestinal microbiota dysbiosis, which is characterized by the elevation of Firmicutes in HFD mice, and notably amplified the abundance of probiotic Lactobacillus. In addition, supported by flow cytometry and other analyses, we observed that limonin upregulated the ILC3-IL22-IL22R pathway, enhancing phosphorylated STAT3 (pSTAT3) in intestinal epithelial cells (IECs), thereby reducing lipid transporter expression. In conclusion, our study revealed that limonin exerted a promising preventive effect against HFD-induced dyslipidemia by the mitigation of the intestinal barrier function and intestinal microbiota, and its mechanism was related to the upregulation of the ILC3-IL22-IL22R pathway.

Paraxylines A-G: Highly oxygenated preurianin-type limonoids with immunomodulatory TLR4 and cytotoxic activities from the stem bark of Dysoxylum parasiticum.

Seven previously undescribed preurianin-type limonoids, namely paraxylines A-G, and three known analogs were isolated from stem bark of Dysoxylum parasiticum. The structures, including absolute configurations, were established through spectroscopic analyses, quantum chemical calculations using the density functional theory method, as well as the DP4+ algorithm. Paraxylines A-G were identified as the first preurianin-type with full substitution at C, D-rings, leading to the highly oxygenated seco-limonoids skeleton. The secreted alkaline phosphate assay against an engineered human and murine TLR4 of HEK-Blue cells was performed to evaluate the immune regulating effects. Among them, paraxyline B was found to be a remarkable TLR4 agonist whereas two analogs (toonapubesins A and B) were found to antagonise lipopolysaccharide stimulation of the TLR4 pathway. Paraxylines A and C-E acted either as agonists or antagonists depending on the origin of the TLR4 receptor (human or mouse). The effect of these selected compounds on the expression of pro-inflammatory cytokines TNF-α, IL-1α, IL-1ß, and IL-6 of the NF-κB signaling pathway were examined in macrophage cell lines, revealing dose-dependent effects. Additionally, paraxylines A, C, D, and G also presented modest cytotoxic activity against MCF-7 and HeLa cell lines with IC50 values ranging from 23.1 to 43.5 µM.

Effects of limonin on oxidative stress and early apoptosis in oocytes during in vitro maturation.

To investigate the effects of limonin (Lim) on oxidative stress and early apoptosis in bovine oocytes during in vitro maturation (IVM), different concentrations of Lim (0, 10, 20, 50 µmol/L) were added to bovine IVM medium. Oocyte maturation rates and development 24 h after in vitro fertilization (IVF) were examined to determine the optimal Lim concentration. The optimal Lim concentration was added to the IVM medium, and 0 µmol/L Lim was used as the control. Immunofluorescence staining was used to detect the abnormal rate of spindle assembly, reactive oxygen species (ROS), glutathione (GSH), mitochondrial membrane potential (MMP) levels, mitochondrial distribution, and the fluorescence intensity of cathepsin B (CB)-active LC3 protein. RT‒qPCR was used to detect the mRNA expression levels of antioxidant-, apoptosis- and autophagy-related genes in oocytes. The total number of blastocysts and the proportion of apoptotic cells among blastocysts were detected. The results showed that the PBI ejection rate, cleavage rate and blastocyst rate of bovine oocytes in the 20 µmol/L Lim group were significantly higher than those in the control group (P < 0.05). Compared with those in the control group, ROS levels, abnormal mitochondrial distribution, the proportion of abnormal spindle assembly, CB activity and LC3 protein fluorescence intensity of oocytes in the 20 µmol/L Lim group were significantly decreased (P < 0.05), and GSH and MMP levels were significantly increased (P < 0.05). The expression of antioxidant genes (Prdx3, Prdx6, Sirt1) and antiapoptotic genes (Bcl-xl, Survivin) were significantly upregulated (P < 0.05), and the expression levels of proapoptotic genes (Caspase-4, BAX) and autophagy-related genes (LC3) were significantly downregulated (P < 0.05). The total number of cells among in vitro fertilized embryos was significantly increased (P < 0.05), and the apoptosis rate of blastocysts was significantly decreased (P < 0.05). Here, we show that Lim exerts positive effects on bovine oocyte IVM by regulating REDOX homeostasis, reducing spindle damage and enhancing mitochondrial function during IVM, thereby inhibiting oocyte apoptosis and autophagy.

Nimbolide Exhibits Potent Anticancer Activity Through ROS-Mediated ER Stress and DNA Damage in Human Non-small Cell Lung Cancer Cells.

The non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancers. It is usually diagnosed at an advanced stage with poor prognosis. Nimbolide (NB), a terpenoid limonoid isolated from the flowers and leaves of neem tree, possesses anticancer properties in various cancer cell lines. However, the underlying mechanism of its anticancer effect on human NSCLC cells remains unclear. In the present study, we investigated the effect of NB on A549 human NSCLC cells. We found that NB treatment inhibits A549 cells colony formation in a dose-dependent manner. Mechanistically, NB treatment increases cellular reactive oxygen species (ROS) level, leading to endoplasmic reticulum (ER) stress, DNA damage, and eventually induction of apoptosis in NSCLC cells. Furthermore, all these effects of NB were blocked by pretreatment with antioxidant glutathione (GSH), the specific ROS inhibitor. We further knockdown CHOP protein by siRNA markedly reduced NB-induced apoptosis in A549 cells. Taken together, our findings reveal that NB is an inducer of ER stress and ROS; these findings may contribute to increasing the therapeutic efficiency of NSCLC.

Limonoids and alkaloids from Tetradium austrosinense (Hand.-Mazz.) T.G.Hartley.

A pair of new enantiomeric indolopyridoquinazoline-type alkaloids, (+)-1,7S,8R- and (-)-1,7R,8S-trihydroxyrutaecarpine (3a and 3b), and a new limonoid-tyrosamine hybrid, austrosinin (8), along with six known alkaloids and limonoids, were isolated from the stems with leaves of Tetradium austrosinense. Their structures were elucidated on the basis of analysis of MS, NMR, ECD and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations, as well as proposed biosynthetic pathway. An anti-inflammatory bioassay in vitro showed 8 had significant immunosuppressive effect against the production of pro-inflammatory cytokine TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells.