ABSTRACT
Oleogum resins of the genus Commiphora have been used in traditional medicines for centuries. More than 200 Commiphora species exhibit highly variable phytochemical compositions. A novel highly selective, sensitive, accurate HPLC-MS/MS method was developed and validated to quantify five characteristic phytosteroids and furanosesquiterpenoids, namely (E)-guggulsterone, (Z)-guggulsterone, curzerenone, furanoeudesma-1,3-diene, and myrrhone. The resulting contents and additionally GC analysis were used to classify and differentiate Commiphora oleogum resins of the species C. myrrha, C. erythraea, C. mukul, C. holtziana, C. confusa, and C. kua, as well as unspecified resins. Interestingly, a Commiphora sample from Ogaden, Ethiopia, comprised 446 ng/mg guggulsterones presumed to be unique to C. mukul from the Indian subcontinent. However, Commiphora from Ogaden differed considerably from C. mukul in respect to guggulsterones isomer's ratio. Moreover, the cytotoxicity of Commiphora extracts, essential oils, botanical drugs containing Commiphora, and pure compounds against the epidermoid carcinoma A431, malignant melanoma RPMI-7951 and SK-MEL-28 cells was investigated in vitro. Thereby, especially C. mukul extract and C. myrrha essential oil exhibited high cytotoxicity against skin cancer cells with IC50 of 2.9-10.9 µg/mL, but were less toxic to normal keratinocytes. In summary, Commiphora oleogum resins and its phytochemicals warrant further investigation aiming at chemotaxonomical classification as well as application in skin cancer treatment.
Subject(s)
Oils, Volatile , Skin Neoplasms , Commiphora/chemistry , Humans , Phytochemicals/pharmacology , Plant Extracts/chemistry , Resins, Plant/chemistry , Resins, Plant/pharmacology , Skin Neoplasms/drug therapy , Tandem Mass SpectrometryABSTRACT
Herein, a series of aryl-substituted derivatives of 3-amino-1-aryl-9-methoxy-1H-benzo[f]chromene-2-carbonitriles (4a-4q) were designed and synthesized via reaction of 7-methoxy-2-naphthol with a mixture of appropriate aromatic aldehydes and malononitrile under microwave conditions. Among the tested benzochromene, the known compound 4e and four novel compounds 4f, 4j, 4k, 4m exhibited the highest cytotoxicity towards a panel of six human cancer cell lines MDA-MB-231, A549, HeLa, MIA PaCa-2, RPMI 7951, and PC-3. Compound 4j with 2,4-dichloro substitution on the pendant phenyl ring exhibited the highest broad-spectrum cytotoxicity towards all tested cancer cell lines. Compounds 4e, 4f, 4j, 4k, 4m were further selected to study the mechanism of cellular toxicity using the triple-negative breast cancer cells MDA-MB-231. Compounds 4e, 4f, 4j, 4k, 4m induced accumulation of the treated MDA-MB-231 cells in the S phase and 4k additionally in the G2/M phase of the cell cycle. Compounds 4e, 4f, 4j, 4k, 4m induced dissipation of mitochondrial transmembrane potential and activation of caspase 3/7 in MDA-MB-231 cells with 4j being one of the most active. In an in vivo model, compound 4j and less efficiently 4e and 4f inhibited growth and proliferation and triggered DNA fragmentation in MDA-MB-231 xenografts grown on chick chorioallantoic membranes. SAR study confirmed that the 2,4-dichloro substitution pattern on the pendant phenyl ring enhanced the cytotoxic activity of benzochromene.
Subject(s)
Antineoplastic Agents/pharmacology , Benzopyrans/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Benzopyrans/chemical synthesis , Benzopyrans/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Structure-Activity RelationshipABSTRACT
Boswellic acids, and particularly 11-keto-boswellic acids, triterpenoids derived from the genus Boswellia (Burseraceae), are known for their anti-inflammatory and potential antitumor efficacy. Although boswellic acids generally occur as α-isomers (oleanane type) and ß-isomers (ursane type), 11-keto-boswellic acid (KBA) was found only as the ß-isomer, ß-KBA. Here, the existence and natural occurrence of the respective α-isomer, 11-keto-α-boswellic acid (α-KBA), is demonstrated for the first time. Initially, α-KBA was synthesized and characterized by high-resolution mass spectrometry (HR-MS) and nuclear magnetic resonance (NMR) spectroscopy, and a highly selective, sensitive, and accurate high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) method was developed by Design of Experiments (DoE) using a pentafluorophenyl stationary phase. This method allowed the selective quantification of individual 11-keto-boswellic acids and provided evidence for α-KBA in Boswellia spp. oleogum resins. The contents of α-KBA as well as further boswellic acids and the composition of essential oils were used to chemotaxonomically classify 41 Boswellia oleogum resins from 9 different species. Moreover, α-KBA exhibited cytotoxicity against three treatment-resistant triple-negative breast cancer (TNBC) cell lines in vitro and also induced apoptosis in MDA-MB-231 xenografts in vivo. The respective ß-isomer and the acetylated form demonstrate higher cytotoxic efficacies against TNBC cells. This provides further insights into the structure-activity relationship of boswellic acids and could support future developments of potential anti-inflammatory and antitumor drugs.
Subject(s)
Antineoplastic Agents/pharmacology , Boswellia/chemistry , Triple Negative Breast Neoplasms/pathology , Triterpenes/pharmacology , Animals , Antineoplastic Agents/chemistry , Cell Death/drug effects , Cell Line, Tumor , Chickens , Humans , Isomerism , Triterpenes/chemical synthesis , Triterpenes/chemistry , Triterpenes/isolation & purificationABSTRACT
In this study, a series of novel N-feruloyl dipeptides (10-17) have been synthesized through the coupling of N-feruloyl amino acids (6-9) with glycine/alanine methyl ester hydrochloride. Structures of the peptides were assigned using 1D and 2D NMR and HRESIMS. According to initial in vitro cytotoxic screening against the cervix carcinoma cell line KB-3-1, aromatic dipeptides (12, 13, 16, 17) were the most potent ones among all tested feruloyl dipeptides. Accordingly, these peptides were further intensively investigated as potential anticancer agents against a panel of ten cancer cell lines from different tissue origin. Based on that, compound 17 showed the strongest cytotoxic efficiency towards the whole panel of tested cell lines with IC50 values from 2.1 to 7.9 µM. By contrast, the dipeptides 12, 13 and 16 showed moderate to weak cytotoxicity (IC50 16.1-28.3 or >30, 5.7-21.9 and 3.9-21.2 or ≥30 µM, respectively). Mechanistically, compound 17 induced a strong dissipation of the mitochondrial transmembrane potential and an early activation of caspase 3/7 in the triple-negative MDA-MB-231 breast cancer cell line. In an in vivo model, compound 17 inhibited growth, proliferation and induced apoptosis in MDA-MB-231 xenografted onto the chick chorioallantoic membrane. All the synthesized compounds were also tested against a set of pathogenic bacterial strains, displaying no potential activity.
Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Dipeptides/chemistry , Dipeptides/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Proliferation/drug effects , Chick Embryo , Dipeptides/chemical synthesis , Drug Design , Drug Screening Assays, Antitumor , Female , Humans , Membrane Potential, Mitochondrial/drug effects , Neoplasms/drug therapy , Neoplasms/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/metabolismABSTRACT
Ring-substituted 1-hydroxynaphthalene-2-carboxanilides were previously investigated for their antimycobacterial properties. In our study, we have shown their antiproliferative and cell death-inducing effects in cancer cell lines. Cell proliferation and viability were assessed by WST-1 assay and a dye exclusion test, respectively. Cell cycle distribution, phosphatidylserine externalization, levels of reactive oxygen or nitrogen species (RONS), mitochondrial membrane depolarization, and release of cytochrome c were estimated by flow cytometry. Levels of regulatory proteins were determined by Western blotting. Our data suggest that the ability to inhibit the proliferation of THP-1 or MCF-7 cells might be referred to meta- or para-substituted derivatives with electron-withdrawing groups -F, -Br, or -CF3 at anilide moiety. This effect was accompanied by accumulation of cells in G1 phase. Compound 10 also induced apoptosis in THP-1 cells in association with a loss of mitochondrial membrane potential and production of mitochondrial superoxide. Our study provides a new insight into the action of salicylanilide derivatives, hydroxynaphthalene carboxamides, in cancer cells. Thus, their structure merits further investigation as a model moiety of new small-molecule compounds with potential anticancer properties.
Subject(s)
Anilides/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Mitochondria/drug effects , Naphthols/chemistry , Anilides/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Cycle/drug effects , Cell Survival/drug effects , Humans , MCF-7 Cells , Membrane Potential, Mitochondrial/drug effects , Mitochondria/metabolism , Molecular Structure , Reactive Oxygen Species/metabolism , Salicylanilides/chemistry , Salicylanilides/pharmacology , Structure-Activity Relationship , Superoxides/metabolism , THP-1 CellsABSTRACT
Triple negative human breast cancer (TNBC) is an aggressive cancer subtype with poor prognosis. Besides the better-known artemisinin, Artemisia annua L. contains numerous active compounds not well-studied yet. High-performance liquid chromatography coupled with diode-array and mass spectrometric detection (HPLC-DAD-MS) was used for the analysis of the most abundant compounds of an Artemisia annua extract exhibiting toxicity to MDA-MB-231 TNBC cells. Artemisinin, 6,7-dimethoxycoumarin, arteannuic acid were not toxic to any of the cancer cell lines tested. The flavonols chrysosplenol d and casticin selectively inhibited the viability of the TNBC cell lines, MDA-MB-231, CAL-51, CAL-148, as well as MCF7, A549, MIA PaCa-2, and PC-3. PC-3 prostate cancer cells exhibiting high basal protein kinase B (AKT) and no ERK1/2 activation were relatively resistant, whereas MDA-MB-231 cells with high basal ERK1/2 and low AKT activity were more sensitive to chrysosplenol d treatment. In vivo, chrysosplenol d and casticin inhibited MDA-MB-231 tumor growth on chick chorioallantoic membranes. Both compounds induced mitochondrial membrane potential loss and apoptosis. Chrysosplenol d activated ERK1/2, but not other kinases tested, increased cytosolic reactive oxygen species (ROS) and induced autophagy in MDA-MB-231 cells. Lysosomal aberrations and toxicity could be antagonized by ERK1/2 inhibition. The Artemisia annua flavonols chrysosplenol d and casticin merit exploration as potential anticancer therapeutics.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Artemisia annua/chemistry , Flavones/pharmacology , MAP Kinase Signaling System/drug effects , Animals , Antineoplastic Agents, Phytogenic/chemistry , Cell Line, Tumor , Cell Membrane Permeability/drug effects , Cell Survival/drug effects , Disease Models, Animal , Female , Flavones/chemistry , Flavonoids/chemistry , Flavonoids/pharmacology , Flavonols/chemistry , Flavonols/pharmacology , Humans , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Triple Negative Breast Neoplasms , Xenograft Model Antitumor AssaysABSTRACT
Serum amyloid A1 (SAA1) is an apolipoprotein that binds to the high-density lipoprotein (HDL) fraction of the serum and constitutes the fibril precursor protein in systemic AA amyloidosis. We here show that HDL binding blocks fibril formation from soluble SAA1 protein, whereas internalization into mononuclear phagocytes leads to the formation of amyloid. SAA1 aggregation in the cell model disturbs the integrity of vesicular membranes and leads to lysosomal leakage and apoptotic death. The formed amyloid becomes deposited outside the cell where it can seed the fibrillation of extracellular SAA1. Our data imply that cells are transiently required in the amyloidogenic cascade and promote the initial nucleation of the deposits. This mechanism reconciles previous evidence for the extracellular location of deposits and amyloid precursor protein with observations the cells are crucial for the formation of amyloid.
Subject(s)
Amyloid beta-Protein Precursor/metabolism , Amyloid/metabolism , Serum Amyloid A Protein/metabolism , Amyloidosis , Animals , Cell Line , Clathrin/physiology , Endocytosis , Humans , Macrophages/metabolism , Mice , Models, Biological , Protein AggregatesABSTRACT
Breast cancer is the most common cancer type and a primary cause of cancer mortality among females worldwide. Here, we analyzed the anticancer efficacy of a novel bromochlorinated monoterpene, PPM1, a synthetic analogue of polyhalogenated monoterpenes from Plocamium red algae and structurally similar non-brominated monoterpenes. PPM1, but not the non-brominated monoterpenes, decreased selectively the viability of several triple-negative as well as triple-positive breast cancer cells with different p53 status without significantly affecting normal breast epithelial cells. PPM1 induced accumulation of triple-negative MDA-MB-231 cells with 4N DNA content characterized by decreased histone H3-S10/T3 phosphorylation indicating cell cycle arrest in the G2 phase. Western immunoblot analysis revealed that PPM1 treatment triggered an initial rapid activation of Aurora kinases A/B/C and p21Waf1/Cip1 accumulation, which was followed by accumulation of polyploid >4N cells. Flow cytometric analysis showed mitochondrial potential disruption, caspase 3/7 activation, phosphatidylserine externalization, reduction of the amount polyploid cells, and DNA fragmentation consistent with induction of apoptosis. Cell viability was partially restored by the pan-caspase inhibitor Z-VAD-FMK indicating caspase contribution. In vivo, PPM1 inhibited growth, proliferation, and induced apoptosis in MDA-MB-231 xenografted onto the chick chorioallantoic membrane. Hence, Plocamium polyhalogenated monoterpenes and synthetic analogues deserve further exploration as promising anticancer lead compounds.
Subject(s)
Apoptosis/drug effects , Breast Neoplasms/drug therapy , Cell Cycle Checkpoints/drug effects , Monoterpenes/pharmacology , Antineoplastic Agents/pharmacology , Breast/drug effects , Breast/metabolism , Breast Neoplasms/metabolism , Caspase Inhibitors/pharmacology , Caspases/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , G2 Phase/drug effects , Histones/metabolism , Humans , MCF-7 Cells , Mitochondria/drug effects , Mitochondria/metabolism , Plocamium/chemistry , Rhodophyta/chemistryABSTRACT
Electron tomography is an increasingly powerful method to study the detailed architecture of macromolecular complexes or cellular structures. Applied to amyloid deposits formed in a cell culture model of systemic amyloid A amyloidosis, we could determine the structural morphology of the fibrils directly in the deposit. The deposited fibrils are arranged in different networks, and depending on the relative fibril orientation, we can distinguish between fibril meshworks, fibril bundles, and amyloid stars. These networks are frequently infiltrated by vesicular lipid inclusions that may originate from the death of the amyloid-forming cells. Our data support the role of nonfibril components for constructing fibril deposits and provide structural views of different types of lipid-fibril interactions.
Subject(s)
Amyloid/chemistry , Electron Microscope Tomography/methods , Lipids/chemistry , Amyloid/ultrastructure , Animals , Cells, Cultured , Female , Lipid Bilayers/chemistry , Mice , Serum Amyloid A Protein/chemistryABSTRACT
Pentacyclic triterpenic acids from oleogum resins of Boswellia species are of considerable therapeutic interest. Yet, their pharmaceutical development is hampered by uncertainties regarding botanical identification and the complexity of triterpenic acid mixtures. Here, a highly sensitive, selective, and accurate method for the simultaneous quantification of eight boswellic and lupeolic acids by high-performance liquid chromatography with tandem mass spectrometry detection (HPLC-MS/MS) was developed. The method was applied to the comparative analysis of 41 oleogum resins of the species B. sacra, B. dalzielli, B. papyrifera, B. serrata, B. carterii, B. neglecta, B. rivae, B. frereana, and B. occulta. Multivariate statistical analysis of the data revealed differences in the triterpenic acid composition that could be assigned to distinct Boswellia species and to their geographic growth location. Extracts of the oleogum resins exhibited cytotoxicity against the human, treatment-resistant, metastatic breast cancer cell line MDA-MB-231. Extracts from B. sacra were the most potent ones with an average IC50 of 8.3 ± 0.6 µg/mL. The oleogum resin of the B. sacra was further fractionated to enrich different groups of substances. The cytotoxic efficacy against the cancer cells correlates positively with the contents of pentacyclic triterpenic acids in Boswellia extracts.
Subject(s)
Antineoplastic Agents, Phytogenic/analysis , Boswellia/chemistry , Breast Neoplasms/drug therapy , Pentacyclic Triterpenes/analysis , Resins, Plant/analysis , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Drug Resistance, Neoplasm/drug effects , Female , Humans , Pentacyclic Triterpenes/pharmacology , Resins, Plant/pharmacology , Tandem Mass Spectrometry , Triterpenes/isolation & purification , Triterpenes/pharmacologyABSTRACT
We investigated the cytotoxic potential of the cardenolide glycoside acovenoside A against non-small-cell lung cancer cells. Lung cancer is the leading cause of cancer-related mortality and the second most common cancer diagnosed. Epidemiological studies revealed a direct correlation between the regular administration of cardiac glycosides and a lower incidence of various cancers. Acovenoside A, isolated from the pericarps of Acokanthera oppositifolia, potently inhibited proliferation and induced cytotoxicity in A549 non-small-cell lung cancer cells with an IC50 of 68 ± 3 nM after 48 h of exposure. Compared to the antineoplastic agent doxorubicin, acovenoside A was more potent in inhibiting the viability of A549 cancer cells. Moreover, acovenoside A exhibited selectivity against cancer cells, being significantly less toxic to lung fibroblasts and nontoxic for peripheral blood mononuclear cells. Analysis of the cell cycle profile in acovenoside A-treated A549 cells revealed mitotic arrest, due to accumulation of the G2/M regulators cyclin B1 and CDK1, and cytokinesis failure. Furthermore, acovenoside A affected the mitochondrial membrane integrity and induced production of radical oxygen species, which resulted in induction of canonical apoptosis, manifested by caspase 3 activation and DNA fragmentation. Based on our results, acovenoside A warrants further exploration as a potential anticancer lead.
Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Cardenolides/pharmacology , Lung Neoplasms/drug therapy , Mitosis/drug effects , A549 Cells , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , DNA Fragmentation/drug effects , Doxorubicin/pharmacology , Epidemiologic Studies , Fibroblasts/drug effects , Fibroblasts/metabolism , G2 Phase Cell Cycle Checkpoints/drug effects , Humans , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lung Neoplasms/metabolism , Mitochondrial Membranes/drug effects , Reactive Oxygen Species/metabolismABSTRACT
BACKGROUND: This study was designed to evaluate the effect of arglabin on the NLRP3 inflammasome inhibition and atherosclerotic lesion in ApoE2Ki mice fed a high-fat Western-type diet. METHODS AND RESULTS: Arglabin was purified, and its chemical identity was confirmed by mass spectrometry. It inhibited, in a concentration-dependent manner, interleukin (IL)-1ß and IL-18, but not IL-6 and IL-12, production in lipopolysaccharide and cholesterol crystal-activated cultured mouse peritoneal macrophages, with a maximum effect at ≈50 nmol/L and EC50 values for both cytokines of ≈ 10 nmol/L. Lipopolysaccharide and cholesterol crystals did not induce IL-1ß and IL-18 production in Nlrp3(-/-) macrophages. In addition, arglabin activated autophagy as evidenced by the increase in LC3-II protein. Intraperitoneal injection of arglabin (2.5 ng/g body weight twice daily for 13 weeks) into female ApoE2.Ki mice fed a high-fat diet resulted in a decreased IL-1ß plasma level compared with vehicle-treated mice (5.2±1.0 versus 11.7±1.1 pg/mL). Surprisingly, arglabin also reduced plasma levels of total cholesterol and triglycerides to 41% and 42%, respectively. Moreover, arglabin oriented the proinflammatory M1 macrophages into the anti-inflammatory M2 phenotype in spleen and arterial lesions. Finally, arglabin treatment markedly reduced the median lesion areas in the sinus and whole aorta to 54% (P=0.02) and 41% (P=0.02), respectively. CONCLUSIONS: Arglabin reduces inflammation and plasma lipids, increases autophagy, and orients tissue macrophages into an anti-inflammatory phenotype in ApoE2.Ki mice fed a high-fat diet. Consequently, a marked reduction in atherosclerotic lesions was observed. Thus, arglabin may represent a promising new drug to treat inflammation and atherosclerosis.
Subject(s)
Apolipoprotein E2/deficiency , Atherosclerosis/drug therapy , Carrier Proteins/antagonists & inhibitors , Diet, High-Fat/adverse effects , Inflammasomes/antagonists & inhibitors , Sesquiterpenes/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Atherosclerosis/blood , Atherosclerosis/etiology , Female , Inflammasomes/metabolism , Macrophages/drug effects , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , NLR Family, Pyrin Domain-Containing 3 Protein , Sesquiterpenes/pharmacology , Sesquiterpenes, Guaiane , Treatment OutcomeABSTRACT
The current study aimed to investigate the protective effect of the cardenolide glycoside acovenoside A (AcoA) against doxorubicin-induced cardiotoxicity in mice. AcoA was isolated from the pericarps of Acokanthera oppositifolia to chemical homogeneity and characterized by means of one- and two-dimensional nuclear magnetic resonance spectroscopy. AcoA exhibited relatively low toxicity in mice (LD50 = 223.3 mg/kg bw). Repeated administration of doxorubicin induced cardiotoxicity manifested by reduced activity of myocardial membrane-bound ion pumps and elevated serum biomarkers of myocardial dysfunction, oxidative stress, and inflammation. Pretreatment of doxorubicin-exposed mice with AcoA (11.16 or 22.33 mg/kg bw, i.p.) for 2 weeks after 2 weeks of combined administration of AcoA and doxorubicin protected the animals dose dependently against doxorubicin-induced cardiotoxicity as indicated by normalization of the levels of different myocardial markers of oxidative stress (malondialdehyde, nitric oxide, total antioxidant capacity, and cardiac glutathione), serum myocardial diagnostic marker enzymes (serum cardiac troponin T, creatine kinase isoenzyme MB, aspartate aminotransferase, and lactate dehydrogenase), and inflammatory markers (c-reactive protein, tumor necrosis factor-α, and interleukin-6), as well as myocardial Na(+)/K(+)-ATPase activity. These effects were attributed to the negative impact of AcoA on transcription factors nuclear factor κB and interferon regulatory factor 3/7. Thus acovenoside A might act as a cardioprotective agent to prevent doxorubicin-induced cardiotoxicity.
Subject(s)
Cardenolides/pharmacology , Cardiotonic Agents/pharmacology , Cardiotoxicity/etiology , Cardiotoxicity/prevention & control , Doxorubicin/adverse effects , Animals , Apocynaceae/chemistry , Biocatalysis , Biomarkers/blood , Cardenolides/chemistry , Cardenolides/isolation & purification , Cardiotonic Agents/chemistry , Cardiotonic Agents/isolation & purification , Cardiotoxicity/metabolism , Cardiotoxicity/pathology , DNA Topoisomerases, Type II/metabolism , Interferon Regulatory Factors/metabolism , Male , Mice , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/enzymology , Models, Molecular , Molecular Conformation , Myocardium/metabolism , Myocardium/pathology , NF-kappa B/metabolism , Oxidative Stress/drug effects , Sodium-Potassium-Exchanging ATPase/metabolismABSTRACT
Here we provide evidence that αATA(8,24) (3α-acetyloxy-tir-8,24-dien-21-oic acid) inhibits Akt/mammalian target of rapamycin (mTOR) signaling. αATA(8,24) and other tirucallic acids were isolated from the acetylated extract of the oleo gum resin of Boswellia serrata to chemical homogeneity. Compared with related tirucallic acids, αATA(8,24) was the most potent inhibitor of the proliferation of androgen-insensitive prostate cancer cells in vitro and in vivo, in prostate cancer xenografted onto chick chorioallantoic membranes. αATA(8,24) induced loss of cell membrane asymmetry, caspase-3 activation, and DNA fragmentation in vitro and in vivo. These effects were selective for cancer cells, because αATA(8,24) exerted no overt toxic effects on peripheral blood mononuclear cells or the chick embryo. At the molecular level, αATA(8,24) inhibited the Akt1 kinase activity. Prior to all biochemical signs of cellular dysfunction, αATA(8,24) induced inhibition of the Akt downstream target mTOR as indicated by dephosphorylation of S6K1. This event was followed by decreased expression of cell cycle regulators, such as cyclin D1, cyclin E, and cyclin B1, as well as cyclin-dependent kinases CDK4 and CDK2 and phosphoretinoblastoma protein, which led to inhibition of the cell-cycle progression. In agreement with the mTOR inhibition, αATA(8,24) and rapamycin increased the volume of acidic vesicular organelles. In contrast to rapamycin, αATA(8,24) destabilized lysosomal and mitochondrial membranes and induced reactive oxygen species production in cancer cells. The ability of αATA(8,24) to inhibit Akt/mTOR signaling and to induce simultaneously oxidative stress could be exploited for the development of novel antitumor therapeutics with a lower profile of toxic side effects.
Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Oxidative Stress/drug effects , Prostatic Neoplasms/pathology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism , Triterpenes/chemistry , Triterpenes/pharmacology , Animals , Antineoplastic Agents/isolation & purification , Apoptosis/drug effects , Boswellia/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Chick Embryo , Chorioallantoic Membrane/cytology , Chorioallantoic Membrane/drug effects , Humans , Isomerism , Male , Membrane Potential, Mitochondrial/drug effects , Models, Molecular , Molecular Conformation , Organelles/drug effects , Organelles/metabolism , Reactive Oxygen Species/metabolism , Triterpenes/isolation & purificationABSTRACT
The chick chorioallantoic membrane (CAM) model has been successfully used to study angiogenesis, cancer progression and its pharmacological treatment, tumor pharmacokinetics, and properties of novel nanomaterials. MRI is an attractive technique for non-invasive and longitudinal monitoring of physiological processes and tumor growth. This study proposes an age-adapted cooling regime for immobilization of the chick embryo, enabling high-resolution MRI of the embryo and the CAM tumor xenograft. 64 chick embryos were enrolled in this study. The novel immobilization and imaging protocol was optimized in 29 embryos. From d7 to d18 immobilization of the embryo up to 90 min was achieved by cooling at 4 °C pre-imaging, with cooling times adapted to age. Its application to tumor growth monitoring was evaluated in 15 embryos after xenotransplantation of human MDA-MB-231 breast cancer cells on CAM. Tumor volumes were monitored from d4 to d9 after grafting (d11 to d16 after incubation) applying a T2 -weighted multislice RARE sequence. At d9 after grafting, the tumors were collected and compared with the MRI-derived data by histology and weight measurements. Additional imaging methods comprising DWI, T2 mapping, and the bio-distribution of contrast agents were tested at d9 after grafting in 20 further embryos. With the adaptive cooling regime, motion artifacts could be completely avoided for up to 90 min scan time, enabling high-resolution in ovo imaging. Excellent anatomical details could be obtained in the embryo and tumors. Tumor volumes could be quantified over time. The results prove the feasibility of high-resolution MRI for longitudinal tumor and organ growth monitoring. The suggested method is promising for future applications such as testing tailored and/or targeted treatment strategies, longitudinal monitoring of tumor development, analysis of therapeutic efficacies of drugs, or assessment of tumor pharmacokinetics. The method provides an alternative to animal experimentation.
Subject(s)
Breast Neoplasms/pathology , Magnetic Resonance Imaging/methods , Animals , Cell Line, Tumor , Chick Embryo , Chorioallantoic Membrane , Contrast Media , Diffusion Magnetic Resonance Imaging/methods , Egg White , Egg Yolk , Feasibility Studies , Female , Gadolinium , Heterografts , Humans , Image Processing, Computer-Assisted/methods , Organometallic Compounds , Reproducibility of Results , Temperature , Tumor BurdenABSTRACT
This manuscript has been withdrawn by the Author's request.
ABSTRACT
BACKGROUND: Extracts of oleogum resins of Boswellia trees possess anti-inflammatory activities. Micellar formulations have been developed to increase the oral bioavailability of bioactive boswellic and lupeolic acids. PURPOSE: The current single-dose crossover clinical trial compares for the first time pharmacokinetics/pharmacodynamics of two Boswellia serrata nutraceuticals, native Biotikon® BS-85 and micellar Boswellia-Loges®. METHODS: After oral administration of the study preparations (800 mg) to 20 healthy volunteers, plasma concentrations of 8 boswellic and lupeolic acids were measured by using HPLC-MS/MS for up to 48 h Blood samples collected 2 and 5 h after drug administration were stimulated for 24 h with endotoxic lipopolysaccharide. The release of proinflammatory cytokines analyzed by flow cytometry was used as readout of the pharmacodynamic properties of the preparations. REGISTRATION: German Clinical Trials Register (DRKS) No. DRKS00027369. RESULTS: Administration of the micellar extract significantly increased Cmax, AUC0-48, and shortened Tmax for all boswellic and lupeolic acids compared to native extract. Accordingly, their relative bioavailability increased to 1,720-4,291 % with the highest difference for acetyl-11-keto-ß-boswellic acid (AKBA). Both preparations reduced the release of TNF-α and the native formulation diminished also IL-1ß and IL-6. However, no significant differences were observed between the preparations, except for a higher decrease in IL-1ß by the native formulation Biotikon® BS-85. In a lymphocytic gene reporter cell line, both nutraceuticals similarly inhibited the NF-κB transcription factor activity as well as the TNF-α release, yet the native formulation Biotikon®BS-85 was more efficient in inhibiting TNF-α. CONCLUSION: Administration of the micellar Boswellia serrata nutraceutical increased the oral bioavailability of boswellic and lupeolic acids. Yet, the increase in plasma concentration did not enhance the anti-inflammatory efficacy of the micellar extract compared to the native extract in this ex vivo model.
Subject(s)
Boswellia , Cross-Over Studies , Micelles , Plant Extracts , Triterpenes , Humans , Plant Extracts/pharmacology , Plant Extracts/pharmacokinetics , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Boswellia/chemistry , Adult , Male , Triterpenes/pharmacokinetics , Triterpenes/pharmacology , Young Adult , Healthy Volunteers , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/administration & dosage , Female , Biological Availability , Dietary Supplements , Administration, Oral , Cytokines/bloodABSTRACT
Introduction: The use of Complementary and Integrative Medicine (CIM) is very popular among the general population in Germany. However, international studies show that nurses, physicians, and other health care professionals (HCPs) at hospitals often do not feel sufficiently informed about different CIM approaches. Moreover, they do not feel trained enough to counsel their patients appropriately. In the German-speaking context, particularly within university hospitals, research on this subject is scarce. Therefore, the aim of this explorative study was to evaluate attitudes, subjective knowledge, and needs regarding CIM among HCPs with direct patient interaction across all four university hospitals in the federal state of Baden-Württemberg, Germany (Tübingen, Ulm, Freiburg, Heidelberg). Methods: The multicenter, cross-sectional, anonymous full survey was conducted online using a self-developed, semi-structured, web-based questionnaire. Recruitment took place via all-inclusive e-mail distribution lists of all four university hospitals. Results: A total of n = 2,026 participants (response rate varied by location from about 5 to 14%) fully answered the questionnaire. Nurses constituted the largest professional group (n = 1,196; 59%), followed by physicians (n = 567; 28%), physiotherapists (n = 54), psychologists (n = 48), midwives (n = 37), and other professions (n = 124). More than two-thirds (71%, n = 1,437) of the participants were female and 14% (n = 286) reported additional training in CIM. The overall attitude toward CIM (10-point Likert scale, 10 = "very favorable") was clearly positive (M ± SD: 7.43 ± 2.33), with notable differences between professional groups: midwives (9.05 ± 1.18), physiotherapists (8.44 ± 1.74), and nurses (8.08 ± 1.95) expressed the highest support, whereas physicians (5.80 ± 2.39) the lowest. 42% of the participants incorporated CIM in patient care (from 33% of physicians to 86% of midwives). Overall, relaxation therapy (n = 1,951; 96%), external applications (n = 1,911; 94%), massage (n = 1,836; 91%), and meditation/mindfulness (n = 1,812; 89%) were rated as useful or rather useful for patients. The average self-assessed knowledge level about CIM was moderate (M ± SD: 5.83 ± 2.03). Most of the participants found CIM training at university hospitals important and saw research about CIM as one of the tasks of university hospitals. The participants expressed the highest interest in education for acupuncture/acupressure, relaxation therapies, and manual medicine. Discussion: This comprehensive survey of health care professionals (HCPs) at university hospitals in Germany reveals a clearly positive disposition toward CIM, aligning with findings from other hospital-based surveys and highlighting differences among professional groups. While most therapies deemed beneficial for patient care are supported by positive evidence, further research is required for others. Given the average self-reported knowledge of CIM, targeted education is essential to meet the needs of both HCPs and patients and to ensure the provision of evidence-based information on the risks and benefits of CIM.
ABSTRACT
The mammalian target of rapamycin (mTOR) is a key regulator of cell growth and its uncontrolled activation is a hallmark of cancer. Moreover, mTOR activation has been implicated in the resistance of cancer cells to many anticancer drugs, rendering this pathway a promising pharmacotherapeutic target. Here we explored the capability of a semisynthetic compound to intercept mTOR signaling. We synthesized and chemically characterized a novel, semisynthetic triterpenoid derivative, 3-cinnamoyl-11-keto-ß-boswellic acid (C-KßBA). Its pharmacodynamic effects on mTOR and several other signaling pathways were assessed in a number of prostate and breast cancer cell lines as well as in normal prostate epithelial cells. C-KßBA exhibits specific antiproliferative and proapoptotic effects in cancer cell lines in vitro as well as in PC-3 prostate cancer xenografts in vivo. Mechanistically, the compound significantly inhibits the cap-dependent transition machinery, decreases expression of eukaryotic translation initiation factor 4E and cyclin D1, and induces G(1) cell-cycle arrest. In contrast to conventional mTOR inhibitors, C-KßBA downregulates the phosphorylation of p70 ribosomal S6 kinase, the major downstream target of mTOR complex 1, without concomitant activation of mTOR complex 2/Akt and extracellular signal-regulated kinase pathways, and independently of protein phosphatase 2A, liver kinase B1/AMP-activated protein kinase/tuberous sclerosis complex, and F12-protein binding. At the molecular level, the compound binds to the FKBP12-rapamycin-binding domain of mTOR with high affinity, thereby competing with the endogenous mTOR activator phosphatidic acid. C-KßBA represents a new type of proapoptotic mTOR inhibitor that, due to its special mechanistic profile, might overcome the therapeutic drawbacks of conventional mTOR inhibitors.
Subject(s)
Apoptosis/drug effects , Cell Proliferation/drug effects , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/metabolism , TOR Serine-Threonine Kinases/antagonists & inhibitors , Triterpenes/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Cycle Checkpoints/drug effects , Down-Regulation/drug effects , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , G1 Phase/drug effects , Humans , Male , Phosphorylation/drug effects , Prostatic Neoplasms/pathology , Protein Interaction Domains and Motifs , Signal Transduction/drug effects , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/metabolismABSTRACT
Vascular cells are particularly susceptible to oxidative stress that is believed to play a key role in the pathogenesis of cardiovascular disorders. Thioredoxin-1 (Trx-1) is an oxidative stress-limiting protein with anti-inflammatory and anti-apoptotic properties. In contrast, its truncated form (Trx-80) exerts pro-inflammatory effects. Here we analyzed whether Trx-80 might exert atherogenic effects by promoting macrophage differentiation into the M1 pro-inflammatory phenotype. Trx-80 at 1 µg/ml significantly attenuated the polarization of anti-inflammatory M2 macrophages induced by exposure to either IL-4 at 15 ng/ml or IL-4/IL-13 (10 ng/ml each) in vitro, as evidenced by the expression of the characteristic markers, CD206 and IL-10. By contrast, in LPS-challenged macrophages, Trx-80 significantly potentiated the differentiation into inflammatory M1 macrophages as indicated by the expression of the M1 cytokines, TNF-α and MCP-1. When Trx-80 was administered to hyperlipoproteinemic ApoE2.Ki mice at 30 µg/g body weight (b.w.) challenged either with LPS at 30 µg/30 g (b.w.) or IL-4 at 500 ng/30 g (b.w.), it significantly induced the M1 phenotype but inhibited differentiation of M2 macrophages in thymus and liver. When ApoE2.Ki mice were challenged once weekly with LPS for 5 weeks, they showed severe atherosclerotic lesions enriched with macrophages expressing predominantly M1 over M2 markers. Such effect was potentiated when mice received daily, in addition to LPS, the Trx-80. Moreover, the Trx-80 treatment led to a significantly increased aortic lesion area. The ability of Trx-80 to promote differentiation of macrophages into the classical proinflammatory phenotype may explain its atherogenic effects in cardiovascular diseases.