-
Journal of Ethnopharmacology Oct 2021Euphorbia fischeriana S. (E. fischeriana) is a classic Chinese herb with toxicity that is mainly used for cancer treatment and in insect repellent, anti-inflammatory and...
ETHNOPHARMACOLOGICAL RELEVANCE
Euphorbia fischeriana S. (E. fischeriana) is a classic Chinese herb with toxicity that is mainly used for cancer treatment and in insect repellent, anti-inflammatory and anti-edema applications (Liu et al., 2001). 12-Deoxyphorbol13-palmitate (DP), a tetracyclic diterpene monomer compound, was extracted from the roots of E. fischeriana by our research groups.
AIM
Previous studies found that DP could inhibit the proliferation of leukemia cells in vitro. However, the underlying mechanism of DP in leukemia is unknown. Hence, DP's pharmacological effect on leukemia cells was investigated in this study.
MATERIALS AND METHODS
DP was obtained from the Natural Medicine Chemistry Laboratory of Qiqihaer Medical University. In vitro, K562 cells and HL60 cells were incubated with DP or DP combined with LY294002 at different concentrations. Cell proliferation and apoptosis were detected by the relevant experimental methods. In vivo, nude mouse xenograft models were established by injecting K562 cells. DP was intraperitoneally administered to observe the influence on the growth of transplanted tumors. Gene detection and immunoblot analysis were performed to validate the mechanisms.
RESULTS
The cell counting kit-8 (CCK-8) assay proved that DP inhibited the growth of K562 and HL60 cells in a time- or dose-dependent manner. At 12 h, DP could induce apoptosis by Annexin V-FITC/propidium iodide (PI) dual labeling, loss of mitochondrial membrane potential (MMP), intracellular reactive oxygen species (ROS), acridine orange/ethidium bromide (AO/EB) staining and transmission electron microscopy (TEM) observation in K562 or HL60 cells. Furthermore, in an assay of gene and protein expression, we found that DP could downregulate the gene and protein expression levels of Bcl-2, upregulate the gene and protein expression levels of Bax and Bim, and downregulate the protein expression levels of PI3k, p-Akt, and p-FoxO3a. Moreover, the effects of DP on proliferation and apoptosis in K562 cells were enhanced by LY294002. Then, we tested the antitumor effects of DP in vivo. Nude mouse xenograft models were established by subcutaneously injecting K562 cells. We found that tumor volume was significantly decreased in DP-treated xenograft nude mice. Morphologic changes, apoptosis degree, and related gene and protein expression levels in transplanted tumor tissue of DP-treated nude mice were assessed by different experimental methods.
CONCLUSIONS
The in vivo and in vitro experimental results indicated that DP might inhibit the proliferation and induce the apoptosis of leukemia cells, which might be a result of suppressing the PI3k/Akt signaling pathways.
Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Proliferation; Euphorbia; HL-60 Cells; Humans; K562 Cells; Leukemia; Membrane Potential, Mitochondrial; Mice; Mice, Inbred BALB C; Mice, Nude; Phorbol Esters; Phosphatidylinositol 3-Kinase; Proto-Oncogene Proteins c-akt; Reactive Oxygen Species; Signal Transduction; Xenograft Model Antitumor Assays
PubMed: 33524514
DOI: 10.1016/j.jep.2021.113889 -
Neurotoxicology Dec 2022Amphetamine (AMPH) causes the degeneration of dopamine terminals in the central nervous system. The mechanisms for this damage are unclear. We found AMPH reduced level...
Amphetamine (AMPH) causes the degeneration of dopamine terminals in the central nervous system. The mechanisms for this damage are unclear. We found AMPH reduced level of GAP-43 in the striatum of rats that receives rich dopaminergic terminals. Using PC12 cells as dopaminergic neuronal models, we further found that AMPH inhibited GAP-43 and GAP-43 phosphorylation in PC12 cells. The reduced GAP-43 was correlated with neurite injury of PC12 cells. The PKCβ1, an upstream molecule of GAP-43, was also inhibited by AMPH. Phorbol 12-myristate 13-acetate (PMA) as a specific activator of PKC increased levels of PKCβ1 and GAP-43, and efficiently prevented neurite degeneration of PC12 cells induced by AMPH. On the other side, enzastuarin, an inhibitor of PKC, decreased levels of PKCβ1 and GAP-43, and caused neurite injury of PC12 cells. Together, our results suggest that AMPH induces neurite injury in PC12 cells through inhibiting PKCβ1/GAP-43 pathway.
Topics: Animals; Rats; Amphetamine; PC12 Cells; Neurites; GAP-43 Protein; Tetradecanoylphorbol Acetate; Dopamine
PubMed: 36150536
DOI: 10.1016/j.neuro.2022.09.004 -
Scientific Reports May 2021Understanding the platelet activation molecular pathways by characterizing specific protein clusters within platelets is essential to identify the platelet activation...
Understanding the platelet activation molecular pathways by characterizing specific protein clusters within platelets is essential to identify the platelet activation state and improve the existing therapies for hemostatic disorders. Here, we employed various state-of-the-art super-resolution imaging and quantification methods to characterize the platelet spatiotemporal ultrastructural change during the activation process due to phorbol 12-myristate 13-acetate (PMA) stimuli by observing the cytoskeletal elements and various organelles at nanoscale, which cannot be done using conventional microscopy. Platelets could be spread out with the guidance of actin and microtubules, and most organelles were centralized probably due to the limited space of the peripheral thin regions or the close association with the open canalicular system (OCS). Among the centralized organelles, we provided evidence that granules are fused with the OCS to release their cargo through enlarged OCS. These findings highlight the concerted ultrastructural reorganization and relative arrangements of various organelles upon activation and call for a reassessment of previously unresolved complex and multi-factorial activation processes.
Topics: Actin Cytoskeleton; Humans; Organelles; Platelet Activation; Tetradecanoylphorbol Acetate
PubMed: 34006947
DOI: 10.1038/s41598-021-89799-9 -
Human Cell May 2022Gut microbial lipopolysaccharides (LPS)-induced inflammatory responses in adipose tissue are associated with the dysfunction of adipocytes, insulin resistance and the...
Gut microbial lipopolysaccharides (LPS)-induced inflammatory responses in adipose tissue are associated with the dysfunction of adipocytes, insulin resistance and the development of metabolic syndrome. The aim of this study is to investigate (1) the effects of LPS on the differentiation and inflammatory responses of THP-1 monocytes and OP9 preadipocytes under serum free conditions and (2) the repressive effects of enzyme-digested Colla Corii Asini (CCAD) and fish gelatin (FGD) on LPS-induced inflammatory responses in THP-1 macrophages and OP9 adipocytes. Immunofluorescence and oil red O staining showed that a serum free medium supplied with phorbol 12-myristate 13-acetate (PMA) could induce differentiation and lipid accumulation in THP-1 cells as well as OP9 cells. ELISA showed that LPS significantly increased interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) secretions in PMA-differentiated THP-1 macrophages in a dose-dependent manner. LPS significantly suppressed lipid accumulation and adiponectin secretions, and enhanced IL-6 secretions in OP9 adipocytes. Both CCAD and FGD significantly reduced the levels of both macrophages- and adipocytes-derived inflammatory cytokines and increased the level of OP9-secreted adiponectin. In conclusion, LPS could induce inflammatory responses in both THP-1 and OP9 cells and cause dysfunction of OP9 adipocytes under the serum free conditions. CCAD and FGD can repress LPS-induced inflammatory responses in both THP-1 macrophages and OP9 adipocytes, and increase the secretion of adiponectin in OP9 adipocytes. They could be used as health care supplements for improving metabolic syndrome.
Topics: Adipocytes; Adiponectin; Animals; Gelatin; Interleukin-6; Lipopolysaccharides; Macrophages; Metabolic Syndrome; Tetradecanoylphorbol Acetate
PubMed: 35359251
DOI: 10.1007/s13577-022-00694-5 -
Journal of Natural Products Dec 2023To investigate the role of the secondary 5-hydroxy group in the activity of the anticancer drug tigilanol tiglate () (Stelfonta), oxidation of this epoxytigliane...
To investigate the role of the secondary 5-hydroxy group in the activity of the anticancer drug tigilanol tiglate () (Stelfonta), oxidation of this epoxytigliane diterpenoid from the Australian rainforest plant was attempted. Eventually, 5-dehydrotigilanol tiglate () proved too unstable to be characterized in terms of biological activity and, therefore, was not a suitable tool compound for bioactivity studies. On the other hand, a series of remarkable skeletal rearrangements associated with the presence of a 5-keto group were discovered during its synthesis, including a dismutative ring expansion of ring A and a mechanistically unprecedented dyotropic substituent swap around the C-4/C-10 bond. Taken together, these observations highlight the propensity of the α-hydroxy-β-diketone system to trigger complex skeletal rearrangements and pave the way to new areas of the natural products chemical space.
Topics: Phorbols; Australia; Diterpenes; Antineoplastic Agents; Biological Products
PubMed: 37991924
DOI: 10.1021/acs.jnatprod.3c00834 -
Nature Chemistry Dec 2022Tigilanol tiglate is a natural product diterpenoid in clinical trials for the treatment of a broad range of cancers. Its unprecedented protein kinase C isoform...
Tigilanol tiglate is a natural product diterpenoid in clinical trials for the treatment of a broad range of cancers. Its unprecedented protein kinase C isoform selectivity make it and its analogues exceptional leads for PKC-related clinical indications, which include human immunodeficiency virus and AIDS eradication, antigen-enhanced cancer immunotherapy, Alzheimer's disease and multiple sclerosis. Currently, the only source of tigilanol tiglate is a rain forest tree, Fontainea picrosperma, whose limited number and restricted distribution (northeastern Australia) has prompted consideration of designed tree plantations to address supply needs. Here we report a practical laboratory synthesis of tigilanol tiglate that proceeds in 12 steps (12% overall yield, >80% average yield per step) and can be used to sustainably supply tigilanol tiglate and its analogues, the latter otherwise inaccessible from the natural source. The success of this synthesis is based on a unique strategy for the installation of an oxidation pattern common to many biologically active tiglianes, daphnanes and their analogues.
Topics: Humans; Phorbols; Diterpenes; Protein Kinase Inhibitors; Neoplasms; Protein Kinase C
PubMed: 36192432
DOI: 10.1038/s41557-022-01048-2 -
Immunobiology 2018Atherosclerotic plaques are complex tissues containing many different cell types. Macrophages contribute to inflammation, formation of the necrotic core, and plaque...
Atherosclerotic plaques are complex tissues containing many different cell types. Macrophages contribute to inflammation, formation of the necrotic core, and plaque rupture. We examined whether macrophages in plaque can be activated and compared this to monolayer cells. The volume of calcium in the plaque was compared to the level of macrophage activation measured by total neopterin output. Carotid plaque samples were cut into 3 mm sections and cultured for up to 96 h. Live sections were stimulated with interferon-γ, phytohaemagglutinin or phorbol 12-myristate 13-acetate. Macrophage activation and oxidative stress were monitored by total neopterin (oxidized and non-oxidized 7,8-dihydroneopterin) and neopterin levels every 24 h for up to 4 d. The calcium content of two plaques was investigated by spectral imaging. Direct stimulation of macrophages in plaque sections with interferon-γ caused a sustained increase in neopterin (p = .037) and total neopterin (p = .003). The addition of phorbol 12-myristate 13-acetate to plaque had no significant effect on total neopterin production (p = .073) but increased neopterin (p = .037) whereas phytohaemagglutinin caused a significant increase in both neopterin and total neopterin (p = .0279 and .0168). There was an inverse association (R = 0.91) between the volume of calcium and macrophage activation as measured by total neopterin production in stimulated plaque tissue. Resident macrophages within excised carotid plaque activated either directly or indirectly generate the biomarkers 7,8-dihydroneopterin and neopterin. Macrophage activation rather than the oxidative environment is associated with plaque calcification.
Topics: Calcium; Female; Humans; Interferon-gamma; Macrophage Activation; Macrophages; Male; Oxidative Stress; Phytohemagglutinins; Plaque, Atherosclerotic; Tetradecanoylphorbol Acetate
PubMed: 29605258
DOI: 10.1016/j.imbio.2018.03.002 -
Lab on a Chip Sep 2023Neutrophils are the most abundant circulating white blood cells and one of their critical functions to eliminate pathogenic threats includes the release of extracellular...
Neutrophils are the most abundant circulating white blood cells and one of their critical functions to eliminate pathogenic threats includes the release of extracellular DNA, also known as neutrophil extracellular traps (NETs), which is dysregulated in many diseases including cancer, type 2 diabetes mellitus and infectious diseases. Currently, conventional methods to quantify the NET formation (NETosis) rely on fluorescence antibody-based NET labelling or circulating NET-associated protein detection by ELISA, which are expensive, laborious, and time-consuming. In this work, we employed a novel "virtual staining" using deep convolutional neural networks (CNNs) to facilitate label-free quantification of NETs trapped in a micropillar array in a microfluidic device. Virtual staining is constructed to establish relations between morphological features in phase contrast images and fluorescence features in Sytox-green (DNA dye) images. We first investigated the effect of different learning rates on model training and optimized the learning rate to achieve the best model which can provide outputs close to Sytox green staining based on various reconstruction metrics (, structural similarity (SSIM) and pixel-wise error (MAE, MSE)). The virtual staining of different NET concentrations was investigated which showed a linear correlation with fluorescent staining. As a proof of concept for clinical testing, the model was used to characterize purified neutrophils treated with NETosis inducers, including lipopolysaccharide (LPS), phorbol 12-myristate 13-acetate (PMA), and calcium ionophore (CaI), and successfully detected different NET profiles for different treatments. Collectively, these results demonstrated the potential of using deep learning for enhanced label-free image analysis of NETs for clinical research, drug discovery and point-of-care testing of diseases.
Topics: Humans; Extracellular Traps; Microfluidics; Diabetes Mellitus, Type 2; Neutrophils; Tetradecanoylphorbol Acetate; DNA
PubMed: 37584074
DOI: 10.1039/d3lc00398a -
Journal of the Science of Food and... Sep 2021Jatropha is an oilseed crop with high kernel oil (55-58%) and protein (26-29%) contents, which makes it a good source of biodiesel and animal/aqua-feed. However, the...
BACKGROUND
Jatropha is an oilseed crop with high kernel oil (55-58%) and protein (26-29%) contents, which makes it a good source of biodiesel and animal/aqua-feed. However, the presence of anti-nutritional toxins, such as phorbol esters, lectins, trypsin inhibitor, phytate, and saponins, restricts its use as feed. This paper describes chemical, ultraviolet (UV) radiation, and biological treatments for detoxification of jatropha kernel meal. Raw, defatted, and one-time and two-times mechanically expressed oil samples were analyzed for toxins. Chemical treatment involved heating with 90% methanol and 4% sodium hydroxide. UV treatment was carried out at UV light intensity of 53.4 mW cm for 30 min. For biological treatment, cell-free extract from Pseudomonas aeruginosa (strain PAO1) was mixed with kernel meal for detoxification.
RESULTS
Among treatments, chemical treatment was most effective in reducing all toxins, with phorbol esters in the range 0.034-0.052 mg g , lectin 0.082-10.766 mg g , trypsin inhibitor 10.499-11.350 mg g , phytate 2.475-5.769 mg g , and saponins 0.044-0.098 mg g . Biological treatment reduced all toxins except phytate, whereas UV treatment could not reduce any of toxins and, hence, cannot be used for aqua-feed preparation. Pellets prepared from chemically detoxified kernel meal with the least oil content (defatted) resulted in the highest strength (70.93 N).
CONCLUSION
Chemically treated jatropha kernel meal can be used for aqua-feed pellet preparation because of its low toxin content. The highest compressive strength was obtained for pellets with the least oil content (defatted). Biological treatment time must have been extended for many hours instead of 24 h. Jatropha kernel meal treated chemically can be recommended for aqua-feed manufacturing. © 2021 Society of Chemical Industry.
Topics: Animal Feed; Animals; Aquaculture; Fishes; Food Handling; Jatropha; Phorbol Esters; Phytic Acid; Saponins; Seeds; Trypsin Inhibitors; Ultraviolet Rays
PubMed: 33570746
DOI: 10.1002/jsfa.11154 -
Blood Advances Jan 2022Neutrophil extracellular traps (NETs) are networks of extracellular fibers primarily composed of DNA and histone proteins, which bind pathogens. We investigated NET...
Neutrophil extracellular traps (NETs) are networks of extracellular fibers primarily composed of DNA and histone proteins, which bind pathogens. We investigated NET formation in 12 patients with myelodysplastic syndrome (MDS) and 15 age-adjusted normal controls after stimulation with phorbol-12-myristate-13-acetate (PMA). Histones and neutrophil elastase were visualized by immunostaining. Since NET formation is triggered by reactive oxygen species (ROS), mainly produced by reduced NADP-oxidase and myeloperoxidase (MPO), ROS were analyzed by flow cytometry using hydroethidine, 3'-(p-aminophenyl) fluorescein, and 3'-(hydroxyphenyl) fluorescein. On fluorescence microscopy, PMA-stimulated MDS neutrophils generated fewer NETs than controls (stimulated increase from 17% to 67% vs 17% to 85%) (P = .02) and showed less cellular swelling (P = .04). The decrease in mean fluorescence intensity (MFI) of 4',6-diamidino-2-phenylindole, indicating chromatin decondensation, was significantly less in MDS neutrophils than controls (ΔMFI 3467 vs ΔMFI 4687, P = .03). In addition, the decrease in MFI for fluorescein isothiocyanate, indicating release of neutrophil elastase from cytoplasmic granules, was diminished in patients with MDS (P = .00002). On flow cytometry, less cell swelling after PMA (P = .02) and a smaller decrease in granularity after H2O2 stimulation (P = .002) were confirmed. PMA-stimulated ROS production and oxidative burst activity did not reveal significant differences between MDS and controls. However, inhibition of MPO activity was more easily achieved in patients with MDS (P = .01), corroborating the notion of a partial MPO defect. We conclude that NET formation is significantly impaired in MDS neutrophils. Although we found abnormalities of MPO-dependent generation of hypochloride, impaired ROS production may not be the only cause of deficient NETosis in MDS.
Topics: Extracellular Traps; Humans; Hydrogen Peroxide; Myelodysplastic Syndromes; Neutrophils; Tetradecanoylphorbol Acetate
PubMed: 34653237
DOI: 10.1182/bloodadvances.2021005721