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1.
J Am Chem Soc ; 146(15): 10393-10406, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38569115

RESUMO

Covalent chemistry coupled with activity-based protein profiling (ABPP) offers a versatile way to discover ligands for proteins in native biological systems. Here, we describe a set of stereo- and regiochemically defined spirocycle acrylamides and the analysis of these electrophilic "stereoprobes" in human cancer cells by cysteine-directed ABPP. Despite showing attenuated reactivity compared to structurally related azetidine acrylamide stereoprobes, the spirocycle acrylamides preferentially liganded specific cysteines on diverse protein classes. One compound termed ZL-12A promoted the degradation of the TFIIH helicase ERCC3. Interestingly, ZL-12A reacts with the same cysteine (C342) in ERCC3 as the natural product triptolide, which did not lead to ERCC3 degradation but instead causes collateral loss of RNA polymerases. ZL-12A and triptolide cross-antagonized one another's protein degradation profiles. Finally, we provide evidence that the antihypertension drug spironolactone─previously found to promote ERCC3 degradation through an enigmatic mechanism─also reacts with ERCC3_C342. Our findings thus describe monofunctional degraders of ERCC3 and highlight how covalent ligands targeting the same cysteine can produce strikingly different functional outcomes.


Assuntos
Acrilamida , Diterpenos , Fenantrenos , Humanos , Cisteína/química , Proteômica , Compostos de Epóxi
2.
Molecules ; 29(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611713

RESUMO

This study provides a comprehensive computational exploration of the inhibitory activity and metabolic pathways of 8-methoxypsoralen (8-MP), a furocoumarin derivative used for treating various skin disorders, on cytochrome P450 (P450). Employing quantum chemical DFT calculations, molecular docking, and molecular dynamics (MD) simulations analyses, the biotransformation mechanisms and the active site binding profile of 8-MP in CYP1B1 were investigated. Three plausible inactivation mechanisms were minutely scrutinized. Further analysis explored the formation of reactive metabolites in subsequent P450 metabolic processes, including covalent adduct formation through nucleophilic addition to the epoxide, 8-MP epoxide hydrolysis, and non-CYP-catalyzed epoxide ring opening. Special attention was paid to the catalytic effect of residue Phe268 on the mechanism-based inactivation (MBI) of P450 by 8-MP. Energetic profiles and facilitating conditions revealed a slight preference for the C4'=C5' epoxidation pathway, while recognizing a potential kinetic competition with the 8-OMe demethylation pathway due to comparable energy demands. The formation of covalent adducts via nucleophilic addition, particularly by phenylalanine, and the generation of potentially harmful reactive metabolites through autocatalyzed ring cleavage are likely to contribute significantly to P450 metabolism of 8-MP. Our findings highlight the key role of Phe268 in retaining 8-MP within the active site of CYP1B1, thereby facilitating initial oxygen addition transition states. This research offers crucial molecular-level insights that may guide the early stages of drug discovery and risk assessment related to the use of 8-MP.


Assuntos
Furocumarinas , Metoxaleno , Metoxaleno/farmacologia , Simulação de Acoplamento Molecular , Metabolismo Secundário , Furocumarinas/farmacologia , Compostos de Epóxi
3.
Cells ; 13(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38607078

RESUMO

Insulin-producing pancreatic ß cells play a crucial role in the regulation of glucose homeostasis, and their failure is a key event for diabetes development. Prolonged exposure to palmitate in the presence of elevated glucose levels, termed gluco-lipotoxicity, is known to induce ß cell apoptosis. Autophagy has been proposed to be regulated by gluco-lipotoxicity in order to favor ß cell survival. However, the role of palmitate metabolism in gluco-lipotoxcity-induced autophagy is presently unknown. We therefore treated INS-1 cells for 6 and 24 h with palmitate in the presence of low and high glucose concentrations and then monitored autophagy. Gluco-lipotoxicity induces accumulation of LC3-II levels in INS-1 at 6 h which returns to basal levels at 24 h. Using the RFP-GFP-LC3 probe, gluco-lipotoxicity increased both autophagosomes and autolysosmes structures, reflecting early stimulation of an autophagy flux. Triacsin C, a potent inhibitor of the long fatty acid acetyl-coA synthase, completely prevents LC3-II formation and recruitment to autophagosomes, suggesting that autophagic response requires palmitate metabolism. In contrast, etomoxir and bromo-palmitate, inhibitors of fatty acid mitochondrial ß-oxidation, are unable to prevent gluco-lipotoxicity-induced LC3-II accumulation and recruitment to autophagosomes. Moreover, bromo-palmitate and etomoxir potentiate palmitate autophagic response. Even if gluco-lipotoxicity raised ceramide levels in INS-1 cells, ceramide synthase 4 overexpression does not potentiate LC3-II accumulation. Gluco-lipotoxicity also still stimulates an autophagic flux in the presence of an ER stress repressor. Finally, selective inhibition of sphingosine kinase 1 (SphK1) activity precludes gluco-lipotoxicity to induce LC3-II accumulation. Moreover, SphK1 overexpression potentiates autophagic flux induced by gluco-lipotxicity. Altogether, our results indicate that early activation of autophagy by gluco-lipotoxicity is mediated by SphK1, which plays a protective role in ß cells.


Assuntos
Compostos de Epóxi , Células Secretoras de Insulina , Fosfotransferases (Aceptor do Grupo Álcool) , Células Secretoras de Insulina/metabolismo , Palmitatos/toxicidade , Palmitatos/metabolismo , Autofagia , Glucose/metabolismo
4.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 40(3): 222-228, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38512032

RESUMO

Objective To investigate the effects of triptolide (TP) on microglial M1/M2 polarization after cerebral ischemia-reperfusion (I/R) injury in rats and the underlying molecular mechanism. Methods A rat model of middle cerebral artery occlusion (MCAO) was established. TP was administered to rats at doses of 0.1 and 0.2 mg/kg, with a sham surgery group as the control group. Longa scoring was performed to grade neurological deficits in rats; HE staining was used to observe the morphology of neurons in ischemic brain tissues; neuron-specific nuclear protein (NeuN) immunofluorescence staining was used to measure the number of neurons; and Western blot analysis was used to measure the expression levels of ionised calcium-binding adaptor molecule-1 (Iba1), inducible nitric oxide synthase (iNOS), arginase 1 (Arg1), Toll-like receptor 4 (TLR4), nuclear factor κB (NF-κB), NeuN and caspase-3 in ischemic-brain tissues. The protein levels of interleukin 1ß (IL-1ß) and IL-10 were measured by ELISA. Immunofluorescence double labelling was performed to detect the expression of Arg1 and TLR4 in microglia. Results Compared with the model group, the neurological score of the TP treatment group was significantly reduced and the neuronal damage was significantly alleviated. IL-1ß levels decreased while IL-10 levels increased. The expression levels of iNOS, TLR4, NF-κB and caspase-3 decreased, while the expression levels of Arg1 and NeuN increased. Conclusion TP treatment ameliorates cerebral I/R injury in rats, which may be attributed to the promotion of microglial M2 polarization, thereby reducing the release of inflammatory factors and inhibiting apoptosis.


Assuntos
Isquemia Encefálica , Diterpenos , Fenantrenos , Traumatismo por Reperfusão , Animais , Ratos , Caspase 3 , Interleucina-10 , Microglia , Receptor 4 Toll-Like , NF-kappa B , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Interleucina-1beta , Isquemia Encefálica/tratamento farmacológico , Compostos de Epóxi
5.
Acta Cir Bras ; 39: e391424, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511762

RESUMO

PURPOSE: XinJiaCongRongTuSiZiWan (XJCRTSZW) is a traditional Chinese medicine compound for invigorating the kidney, nourishing blood, and promoting blood circulation. This study aimed to explore the effect of XJCRTSZW on triptolide (TP)-induced oxidative stress injury. METHODS: Adult female Sprague-Dawley rats and human ovarian granulosa cell lines were treated with TP and XJCRTSZW. Hematoxylin and eosin staining, enzyme-linked immunosorbent assay, flow cytometry, CCK-8, JC-1 staining, transmission electron microscopy, reverse transcription-quantitative polymerase chain reaction, and Western blotting were performed in this study. RESULTS: XJCRTSZW treatment observably ameliorated the TP-induced pathological symptoms. Furthermore, XJCRTSZW treatment observably enhanced the TP-induced reduction of estradiol, anti-Mullerian hormone, progesterone, superoxide dismutase, ATP content, mitochondrial membrane potential, p62, and Hsp60 mRNA, and protein levels in vivo and in vitro (p < 0.05). However, TP-induced elevation of follicle stimulating hormone and luteinizing hormone concentrations, malondialdehyde levels, reactive oxygen species levels, apoptosis rate, mitophagy, and the mRNA and protein expressions of LC3-II/LC3-I, PTEN-induced kinase 1 (PINK1), and Parkin were decreased (p < 0.05). In addition, XJCRTSZW treatment markedly increased cell viability in vitro (p < 0.05). CONCLUSIONS: XJCRTSZW protects TP-induced rats from oxidative stress injury via the mitophagy-mediated PINK1/Parkin pathway.


Assuntos
Diterpenos , Mitocôndrias , Mitofagia , Fenantrenos , Adulto , Ratos , Feminino , Humanos , Animais , Ratos Sprague-Dawley , Estresse Oxidativo , Ubiquitina-Proteína Ligases , Transdução de Sinais , Proteínas Quinases/metabolismo , Proteínas Quinases/farmacologia , RNA Mensageiro/metabolismo , Compostos de Epóxi
6.
Artigo em Inglês | MEDLINE | ID: mdl-38508352

RESUMO

Epoxiconazole (EPX) is a triazole fungicide, which has been widely used in pest control of cereal crops. However, its extensive use has led to concerning levels of residue in water bodies, posing substantial risks to aquatic life. In this study, we characterized the toxicological effects of EPX on 6-month-old male and female zebrafish at 70 and 700 µg/L, respectively. The results revealed that EPX exposure markedly increased both body length and weight in zebrafish of both sexes, consequently elevating their condition factor. Besides, EPX exposure resulted in notable alterations in hepatic histopathology. These changes included loosened hepatocyte structure, ballooning degeneration, nucleolysis, and disappearance of cell line, with male zebrafish exhibiting more severe damage. High concentration of EPX also significantly increased hepatic lipid accumulation in male zebrafish, as well as increased hepatic triglyceride (TG) levels. Correspondingly, there was a notable alteration in the transcription of genes including cyp51, hmgcr, and PPAR-γ, which associated with cholesterol and lipid metabolism. Interestingly, with the hepatic transcriptomic analysis, high concentration of EPX produced 195 upregulated and 107 downregulated differential expression genes. Both KEGG and GO analyses identified significant enrichment of these genes in lipid and amino acid metabolism pathways. Notably, some key genes involved in the steroid synthesis pathway were marked upregulated. In addition, molecular docking study confirmed that EPX could bind CYP51 protein well (△G = -7.7 kcal/mol). Taken together, these findings demonstrated the multiple toxic effects of EPX on adult zebrafish.


Assuntos
Compostos de Epóxi , Metabolismo dos Lipídeos , Peixe-Zebra , Animais , Masculino , Feminino , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Simulação de Acoplamento Molecular , Triazóis/toxicidade , Perfilação da Expressão Gênica , Lipídeos
7.
ACS Appl Bio Mater ; 7(4): 2594-2603, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38523342

RESUMO

Repairing articular cartilage damage is challenging due to its low regenerative capacity. In vitro, cartilage regeneration is a potential strategy for the functional reconstruction of cartilage defects. A hydrogel is an advanced material for mimicking the extracellular matrix (ECM) due to its hydrophilicity and biocompatibility, which is known as an ideal scaffold for cartilage regeneration. However, chondrocyte culture in vitro tends to dedifferentiate, leading to fibrosis and reduced mechanical properties of the newly formed cartilage tissue. Therefore, it is necessary to understand the mechanism of modulating the chondrocytes' morphology. In this study, we synthesize photo-cross-linkable bovine serum albumin-glycidyl methacrylate (BSA-GMA) with 65% methacrylation. The scaffolds are found to be suitable for chondrocyte growth, which are fabricated by homemade femtosecond laser maskless optical projection lithography (FL-MOPL). The large-area chondrocyte scaffolds have holes with interior angles of triangle (T), quadrilateral (Q), pentagon (P), hexagonal (H), and round (R). The FL-MOPL polymerization mechanism, swelling, degradation, and biocompatibility of the BSA-GMA hydrogel have been investigated. Furthermore, cytoskeleton and nucleus staining reveals that the R-scaffold with larger interior angle is more effective in maintaining chondrocyte morphology and preventing dedifferentiation. The scaffold's ability to maintain the chondrocytes' morphology improves as its shape matches that of the chondrocytes. These results suggest that the BSA-GMA scaffold is a suitable candidate for preventing chondrocyte differentiation and supporting cartilage tissue repair and regeneration. The proposed method for chondrocyte in vitro culture by developing biocompatible materials and flexible fabrication techniques would broaden the potential application of chondrocyte transplants as a viable treatment for cartilage-related diseases.


Assuntos
Cartilagem Articular , Condrócitos , Compostos de Epóxi , Metacrilatos , Condrócitos/metabolismo , Soroalbumina Bovina/farmacologia , Soroalbumina Bovina/metabolismo , Tecidos Suporte , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Cartilagem Articular/metabolismo
8.
Int J Biol Macromol ; 265(Pt 2): 130569, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553394

RESUMO

The development of equipped bio-based epoxy materials has been gaining much attention recently. Nevertheless, finding the balance between the structure and properties of materials remains a significant challenge. In this work, cellulose-based epoxy (PHPCEP) with "soft" and "hard" cooperative structures was designed and demonstrated to endow bisphenol A diglycidyl ether (BADGE) with excellent toughness, heat resistance, mechanical strength, glass transition temperature, thermal stability, and solvent resistance. When 5 wt% PHPCEP was incorporated into BADGE composites, the resulting materials exhibited the maximum flexural strength (121.9 MPa) and tensile strength (71.4 MPa), a high glass transition temperature (148.3 °C), and 10 wt% PHPCEP/BADGE demonstrated the highest impact strength (70.5 kJ/m2). These figures are 18.8 %, 16.1 %, 21.5 %, and 254.3 % higher than the corresponding values of neat BADGE. The results of dynamic mechanical properties and heat degradation of the cured specimens also suggest that PHPCEP/BADGE materials have superior stiffness and toughness than neat BADGE, which could be attributed to the strong interaction between PHPCEP and BADGE, delivering better thermal stability for the composites compared to the pristine resin. Considering the remarkable effect, this work provides an effective way of highly efficient utilization of abundant cellulose and a high-performance additive for composite materials.


Assuntos
Celulose , Compostos de Epóxi , Celulose/química , Resistência à Tração , Compostos de Epóxi/química , Compostos Benzidrílicos , Resinas Vegetais
9.
Inflammopharmacology ; 32(2): 1263-1275, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467913

RESUMO

This study evaluated the composition and the antinociceptive and anti-inflammatory activity of the crude extracts and two isolated compounds, anamarine (ANA) and 10-epi-olguine (eOL), obtained from the leaves of Cantinoa stricta (Lamiaceae). Crude ethanolic extract (EEt) and dichloromethane extract (DCM), selected based on NMR data, were submitted to pharmacological tests in male Swiss mice. The oral administration of EEt and DCM significantly reduced the second phase of formalin-induced nociception (60%), lipopolysaccharide (LPS)-induced mechanical hyperalgesia (90%), and carrageenan (Cg)-induced edema (25%). ANA and eOL, the major compounds in EEt and DCM extracts, administered orally or locally (in the paw), also reduced the LPS-induced mechanical hyperalgesia (Oral ID50 1.9 and 3.9 mg/kg; Local ID50 93.4 and 677.3 ng, respectively) without changing the thermal acute nociception or the motor performance of the animals. Local administration of ANA and eOL also reduced Cg-induced edema (40 and 23%, respectively). These isolated compounds did not change the mechanical hyperalgesia induced by tumor necrosis factor-α, interleukin-1ß, prostaglandin E2, dibutyryl cyclic AMP, or forskolin but reversed the hyperalgesia induced by dopamine, epinephrine, and phorbol 12-myristate 13-acetate. The hyperalgesia induced by epinephrine was reversed in male but not in female mice, in which this response is not dependent on protein kinase C (PKC). These results suggest that C. stricta extracts possess antinociceptive and anti-inflammatory activity which is related to the presence of ANA and eOL. Differently from the known analgesics, these substances seem to exert their action mainly interfering with the sympathetic component of pain, possibly with PKC.


Assuntos
Compostos de Epóxi , Hiperalgesia , Pironas , Masculino , Feminino , Camundongos , Animais , Hiperalgesia/metabolismo , Pironas/efeitos adversos , Lipopolissacarídeos , Anti-Inflamatórios/uso terapêutico , Analgésicos/uso terapêutico , Carragenina , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Edema/induzido quimicamente , Edema/tratamento farmacológico , Epinefrina
10.
Food Chem ; 447: 139044, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513481

RESUMO

The object of this study was to trace TwHf-derived toxins in raw honey and clarify their acute toxic effect related to the addition of honey or sugars. TwHf flowers, raw honey from TwHf planting base and from beekeepers in high-risk area were detected using LC-MS/MS. The results revealed five target toxins were detected in TwHf flowers; only celastrol was detected in one raw honey sample, as a food safety risk factor, celastrol had been traced back to TwHf flowers from raw honey. In a series of acute toxic tests on zebrafish, toxification effects were observed when honey, mimic honey or sugar was mixed with toxins. The degree of toxicity varied among various sugar-based solutions. At the same mass concentration, they follow this order: raw honey/mimic honey > glucose > fructose. The main toxic target organs of triptolide and celastrol with honey were the heart and liver.


Assuntos
Diterpenos , Mel , Triterpenos Pentacíclicos , Fenantrenos , Tripterygium , Animais , Mel/análise , Cromatografia Líquida , Peixe-Zebra , Espectrometria de Massas em Tandem , Açúcares , Compostos de Epóxi
11.
Chemosphere ; 354: 141705, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494000

RESUMO

Benzo[a]pyrene (BaP), as the typical representative of polycyclic aromatic hydrocarbons (PAHs), is a serious hazard to human health and natural environments. Though the study of microbial degradation of PAHs has persisted for decades, the degradation pathway of BaP is still unclear. Previously, Pontibacillus chungwhensis HN14 was isolated from high salinity environment exhibiting a high BaP degradation ability. Here, based on the intermediates identified, BaP was found to be transformed to 4,5-epoxide-BaP, BaP-trans-4,5-dihydrodiol, 1,2-dihydroxy-phenanthrene, 2-carboxy-1-naphthol, and 4,5-dimethoxybenzo[a]pyrene by the strain HN14. Furthermore, functional genes involved in degradation of BaP were identified using genome and transcriptome data. Heterogeneous co-expression of monooxygenase CYP102(HN14) and epoxide hydrolase EH(HN14) suggested that CYP102(HN14) could transform BaP to 4,5-epoxide-BaP, which was further transformed to BaP-trans-4,5-dihydrodiol by EH(HN14). Moreover, gene cyp102(HN14) knockout was performed using CRISPR/Cas9 gene-editing system which confirmed that CYP102(HN14) play a key role in the initial conversion of BaP. Finally, a novel BaP degradation pathway was constructed in bacteria, which showed BaP could be converted into chrysene, phenanthrene, naphthalene pathways for the first time. These findings enhanced our understanding of microbial degradation process for BaP and suggested the potential of using P. chungwhensis HN14 for bioremediation in PAH-contaminated environments.


Assuntos
Bacillaceae , Naftalenos , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Benzo(a)pireno/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Compostos de Epóxi
12.
J Org Chem ; 89(7): 4971-4978, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38509452

RESUMO

A streamlined and efficient approach to the key epoxide intermediate for the asymmetric synthesis of triazole antifungal agents is presented. This synthesis highlights a P(NMe2)3-mediated nonylidic olefination of α-keto ester, ensuring the exclusive formation of the requisite (Z)-alkene, followed by a highly enantioselective Jacobsen epoxidation to establish the two vicinal stereocenters in a single step. The versatility of this strategy is exemplified through the efficient synthesis of efinaconazole and ravuconazole.


Assuntos
Antifúngicos , Compostos de Epóxi , Antifúngicos/farmacologia , Estereoisomerismo , Alcenos , Triazóis
13.
J Am Chem Soc ; 146(12): 8456-8463, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38479352

RESUMO

Here we report the first total synthesis of the marine macrolide salarin C, a potent anticancer agent, and demonstrate the biomimetic oxidation-Wasserman rearrangement to access salarin A. This synthesis relies on L-proline catalysis to install a chlorohydrin function that masks the sensitive C16-C17 epoxide and potentially mimics the biosynthesis of these compounds where a related chlorohydrin may yield both THF- and epoxide-containing salarins. Additional and key features of the synthesis include (i) macrocycle formation via ring-closing metathesis, (ii) macrocyclic substrate-controlled epoxidation of the C12-C13 allylic alcohol, and (iii) a late-stage Julia-Kocienski olefination to install the side chain. Importantly, this work provides a platform for the synthesis of other salarins and analogues of these potentially important anticancer natural products.


Assuntos
Antineoplásicos , Cloridrinas , Estereoisomerismo , Macrolídeos/química , Compostos de Epóxi/química
14.
Nursing ; 54(4): 50-56, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517502

RESUMO

PURPOSE: Evaluate the effectiveness of the clinical decision support tools (CDSTs), POC Advisor (POCA), and Modified Early Warning System (MEWS) in identifying sepsis risk and influencing time to treatment for inpatients, comparing their respective alert mechanisms. METHODS: This study was conducted at two academic university medical center hospitals. Data from adult inpatients in medical-surgical and telemetry units were analyzed from January 1, 2020, to December 31, 2020. Criteria included sepsis-related ICD-10 codes, antibiotic administration, and ordered sepsis labs. Subsequent statistical analyses utilized Fisher's exact test and Wilcoxon Rank Sum test, focusing on mortality differences by age, sex, and race/ethnicity. RESULTS: Among 744 patients, 143 sepsis events were identified, with 83% already receiving treatment upon CDST alert. Group 1 (POCA alert) showed reduced response time compared with MEWS, while Group 3 (MEWS) experienced longer time to treatment. Group 4 included sepsis events missed by both systems. Mortality differences were not significant among the groups. CONCLUSION: While CDSTs play a role, nursing assessment and clinical judgment are crucial. This study recognized the potential for alarm fatigue due to a high number of CDST-driven alerts, while emphasizing the importance of a collaborative approach for prompt sepsis treatment and potential reduction in sepsis-related mortality.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Compostos de Epóxi , Sepse , Adulto , Humanos , Sepse/diagnóstico , Unidades de Terapia Intensiva , Hospitais , Estudos Retrospectivos
15.
BMC Complement Med Ther ; 24(1): 113, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448925

RESUMO

BACKGROUND: Triptolide is a widely utilized natural anti-inflammatory drug in clinical practice. Aim of this study was to evaluate effects of triptolide on hPDLSCs osteogenesis in an inflammatory setting and to investigate underlying mechanisms. METHODS: Using the tissue block method to obtain hPDLSCs from extracted premolar or third molar. Flow cytometry, osteogenic and adipogenic induction were carried out in order to characterise the features of the cells acquired. hPDLSC proliferative activity was assessed by CCK-8 assay to determine the effect of TNF-α and/or triptolide. The impact of triptolide on the osteogenic differentiation of hPDLSCs was investigated by ALP staining and quantification. Osteogenesis-associated genes and proteins expression level were assessed through PCR and Western blotting assay. Finally, BAY-117,082 was used to study the NF-κB pathway. RESULTS: In the group treated with TNF-α, there was an elevation in inflammation levels while osteogenic ability and the expression of both osteogenesis-associated genes and proteins decreased. In the group co-treated with TNF-α and triptolide, inflammation levels were reduced and osteogenic ability as well as the expression of both osteogenesis-associated genes and proteins were enhanced. At the end of the experiment, both triptolide and BAY-117,082 exerted similar inhibitory effects on the NF-κB pathway. CONCLUSION: The osteogenic inhibition of hPDLSCs by TNF-α can be alleviated through triptolide, with the involvement of the p-IκBα/NF-κB pathway in this mechanism.


Assuntos
Diterpenos , NF-kappa B , Fenantrenos , Fator de Necrose Tumoral alfa , Humanos , Osteogênese , Inibidor de NF-kappaB alfa , Ligamento Periodontal , Transdução de Sinais , Células-Tronco , Inflamação , Compostos de Epóxi
16.
Ecotoxicol Environ Saf ; 272: 116072, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342011

RESUMO

Triptolide (TP) is the major bioactive component of traditional Chinese medicine Tripterygium wilfordii Hook. F., a traditional Chinese medicinal plant categorized within the Tripterygium genus of the Celastraceae family. It is recognized for its therapeutic potential in addressing a multitude of diseases. Nonetheless, TP is known to exhibit multi-organ toxicity, notably hepatotoxicity, which poses a significant concern for the well-being of patients undergoing treatment. The precise mechanisms responsible for TP-induced hepatotoxicity remain unresolved. In our previous investigation, it was determined that TP induces heightened hepatic responsiveness to exogenous lipopolysaccharide (LPS). Additionally, natural killer (NK) cells were identified as a crucial effector responsible for mediating hepatocellular damage in this context. However, associated activating receptors and the underlying mechanisms governing NK cell represented innate lymphoid cell (ILC) activation remained subjects of inquiry and were not yet investigated. Herein, activating receptor Killer cell lectin like receptor K1 (NKG2D) of group 1 ILCs was specifically upregulated in TP- and LPS-induced acute liver failure (ALF), and in vivo blockade of NKG2D significantly reduced group 1 ILC mediated cytotoxicity and mitigated TP- and LPS-induced ALF. NKG2D ligand UL16-binding protein-like transcript 1 (MULT-1) was found upregulated in liver resident macrophages (LRMs) after TP administration, and LRMs did exhibit NK cell activating effect. Furthermore, M1 polarization of LRMs cells was observed, along with an elevation in intracellular tumor necrosis factor (TNF)-α levels. In vivo neutralization of TNF-α significantly alleviated TP- and LPS-induced ALF. In conclusion, the collaborative role of group 1 ILCs and LRMs in mediating hepatotoxicity was confirmed in TP- and LPS-induced ALF. TP-induced MULT-1 expression in LRMs was the crucial mechanism in the activation of group 1 ILCs via MULT-1-NKG2D signal upon LPS stimulation, emphasizing the importance of infection control after TP administration.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Diterpenos , Fenantrenos , Animais , Humanos , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Lipopolissacarídeos/toxicidade , Imunidade Inata , Fenantrenos/toxicidade , Compostos de Epóxi/toxicidade , Células Matadoras Naturais , Macrófagos , Doença Hepática Induzida por Substâncias e Drogas/etiologia
17.
Int Immunopharmacol ; 129: 111677, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38350355

RESUMO

OBJECTIVES: Exosomes are small, membrane-bound vesicles secreted by cells into the extracellular environment. They play a crucial role in various biological processes, including immune response, cell-to-cell signaling, and tumor progression. Exosomes have attracted attention as potential targets for therapeutic intervention, drug delivery, and biomarker detection. In this study, we aimed to isolate exosomes from human RA fibroblasts (hRAF-Exo) and load them with triptolide (TP) to generate engineered exosomes (hRAF-Exo@TP). METHODS: Transmission electron microscopy, particle size analysis, and western blotting for protein detection were employed to characterize hRAF-Exo. Furthermore, a murine model of collagen-induced arthritis (CIA) was employed to observe the distinct affinity of hRAF-Exo@TP towards the afflicted area. RESULTS: Cellular experiments demonstrated the inhibitory effect of hRAF-Exo@TP on the proliferative activity of human RA fibroblasts. Additionally, it exhibited remarkable selectivity for lesion sites in a CIA mouse model. CONCLUSION: Exosomes loaded with TP may enhance the therapeutic effects on RA in mice. Our study provides a promising avenue for the treatment of RA in the future.


Assuntos
Artrite Experimental , Artrite Reumatoide , Diterpenos , Exossomos , Fenantrenos , Humanos , Camundongos , Animais , Exossomos/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Diterpenos/uso terapêutico , Diterpenos/farmacologia , Fenantrenos/uso terapêutico , Fenantrenos/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Compostos de Epóxi
18.
Arch Toxicol ; 98(4): 1095-1110, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369618

RESUMO

Chlorzoxazone (CZX), a benzoxazolone derivative, has been approved for the treatment of musculoskeletal disorders to relieve localized muscle spasm. However, its idiosyncratic toxicity reported in patients brought attention, particularly for hepatotoxicity. The present study for the first time aimed at the relationship between CZX-induced hepatotoxicity and identification of oxirane intermediate resulting from metabolic activation of CZX. Two N-acetylcysteine (NAC) conjugates (namely M1 and M2) and two glutathione (GSH) conjugates (namely M3 and M4) were detected in rat & human microsomal incubations with CZX (200 µM) fortified with NAC or GSH, respectively. The formation of M1-M4 was NADPH-dependent and these metabolites were also observed in urine or bile of SD rats given CZX intragastrically at 10 mg/kg or 25 mg/kg. NAC was found to attach at C-6' of the benzo group of M1 by sufficient NMR data. CYPs3A4 and 3A5 dominated the metabolic activation of CZX. The two GSH conjugates were also observed in cultured rat primary hepatocytes after exposure to CZX. Inhibition of CYP3A attenuated the susceptibility of hepatocytes to the cytotoxicity of CZX (10-400 µM). The in vitro and in vivo studies provided solid evidence for the formation of oxirane intermediate of CZX. This would facilitate the understanding of the underlying mechanisms of toxic action of CZX.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Clorzoxazona , Humanos , Ratos , Animais , Citocromo P-450 CYP3A/metabolismo , Ativação Metabólica , Ratos Sprague-Dawley , Microssomos Hepáticos/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Compostos de Epóxi/metabolismo , Glutationa/metabolismo
19.
J Exp Clin Cancer Res ; 43(1): 58, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413979

RESUMO

BACKGROUND: Advanced prostate cancer (PC) is characterized by insensitivity to androgen deprivation therapy and chemotherapy, resulting in poor outcome for most patients. Thus, advanced PC urgently needs novel therapeutic strategies. Mounting evidence points to splicing dysregulation as a hallmark of advanced PC. Moreover, pharmacologic inhibition of the splicing process is emerging as a promising option for this disease. METHOD: By using a representative androgen-insensitive PC cell line (22Rv1), we have investigated the genome-wide transcriptomic effects underlying the cytotoxic effects exerted by three splicing-targeting drugs: Pladienolide B, indisulam and THZ531. Bioinformatic analyses were performed to uncover the gene structural features underlying sensitivity to transcriptional and splicing regulation by these treatments. Biological pathways altered by these treatments were annotated by gene ontology analyses and validated by functional experiments in cell models. RESULTS: Although eliciting similar cytotoxic effects on advanced PC cells, Pladienolide B, indisulam and THZ531 modulate specific transcriptional and splicing signatures. Drug sensitivity is associated with distinct gene structural features, expression levels and cis-acting sequence elements in the regulated exons and introns. Importantly, we identified PC-relevant genes (i.e. EZH2, MDM4) whose drug-induced splicing alteration exerts an impact on cell survival. Moreover, computational analyses uncovered a widespread impact of splicing-targeting drugs on intron retention, with enrichment in genes implicated in pre-mRNA 3'-end processing (i.e. CSTF3, PCF11). Coherently, advanced PC cells displayed high sensitivity to a specific inhibitor of the cleavage and polyadenylation complex, which enhances the effects of chemotherapeutic drugs that are already in use for this cancer. CONCLUSIONS: Our study uncovers intron retention as an actionable vulnerability for advanced PC, which may be exploited to improve therapeutic management of this currently incurable disease.


Assuntos
Processamento Alternativo , Anilidas , Compostos de Epóxi , Macrolídeos , Neoplasias da Próstata , Pirimidinas , Sulfonamidas , Masculino , Humanos , Íntrons , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Antagonistas de Androgênios , Androgênios , Splicing de RNA , Proteínas Proto-Oncogênicas/genética , Proteínas de Ciclo Celular/genética
20.
Chem Biodivers ; 21(4): e202301860, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403856

RESUMO

The males-produced pheromone blend of the Mormidea v-luteum (Hemiptera, Pentatomidae) consists in two isomers of zingiberenol (1) and three of murgantiol (2). While the absolute configuration of the zingiberenol isomers has been described, the configurations of the murgantiol isomers remained unexplored. So, our objective was to identify the absolute configuration of the murgantiol isomers (2 a-c) in the pheromone blend. To achieve this, we initially performed dehydration of the natural extract followed by enantiomeric resolution and, as a result, the three isomers was identified as (4R,1'S)-murgantiol. By leveraging the fixed cis and trans relationships among all pheromone components, we established the configuration at C-1 for isomers 2 a and 2 b is S, while that of 2 c is R. Finally, employing microchemical Sharples asymmetric dihydroxylation and epoxide ring closure, we determined the absolute configuration of the epoxide ring. Consequently, the natural isomers 2 a, 2 b, and 2 c were identified as (1S,4R,1'S,4'R)-, (1S,4R,1'S,4'S)-, and (1R,4R,1'S,4'S)-murgantiol, respectively.


Assuntos
Hemípteros , Heterópteros , Oryza , Sesquiterpenos , Masculino , Animais , Feromônios , Estereoisomerismo , Compostos de Epóxi
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