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1.
J Cardiovasc Pharmacol ; 84(1): 45-57, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38922585

RESUMO

ABSTRACT: Atherosclerosis (AS) is a chronic progressive disease caused by various factors and causes various cerebrovascular and cardiovascular diseases (CVDs). Reducing the plasma levels of low-density lipoprotein cholesterol is the primary goal in preventing and treating AS. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in regulating low-density lipoprotein cholesterol metabolism. Panax notoginseng has potent lipid-reducing effects and protects against CVDs, and its saponins induce vascular dilatation, inhibit thrombus formation, and are used in treating CVDs. However, the anti-AS effect of the secondary metabolite, 20( S )-protopanaxatriol (20( S )-PPT), remains unclear. In this study, the anti-AS effect and molecular mechanism of 20( S )-PPT were investigated in vivo and in vitro by Western blotting, real-time polymerase chain reaction, enzyme-linked immunosorbent assay, immunofluorescence staining, and other assays. The in vitro experiments revealed that 20( S )-PPT reduced the levels of PCSK9 in the supernatant of HepG2 cells, upregulated low-density lipoprotein receptor protein levels, promoted low-density lipoprotein uptake by HepG2 cells, and reduced PCSK9 mRNA transcription by upregulating the levels of forkhead box O3 protein and mRNA and decreasing the levels of HNF1α and SREBP2 protein and mRNA. The in vivo experiments revealed that 20( S )-PPT upregulated aortic α-smooth muscle actin expression, increased the stability of atherosclerotic plaques, and reduced aortic plaque formation induced by a high-cholesterol diet in ApoE -/- mice (high-cholesterol diet-fed group). Additionally, 20( S )-PPT reduced the aortic expression of CD68, reduced inflammation in the aortic root, and alleviated the hepatic lesions in the high-cholesterol diet-fed group. The study revealed that 20( S )-PPT inhibited low-density lipoprotein receptor degradation via PCSK9 to alleviate AS.


Assuntos
Aorta , Doenças da Aorta , Aterosclerose , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica , Pró-Proteína Convertase 9 , Receptores de LDL , Sapogeninas , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Aterosclerose/genética , Sapogeninas/farmacologia , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Receptores de LDL/metabolismo , Humanos , Masculino , Doenças da Aorta/patologia , Doenças da Aorta/prevenção & controle , Doenças da Aorta/metabolismo , Doenças da Aorta/genética , Doenças da Aorta/tratamento farmacológico , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Proteólise/efeitos dos fármacos , Células Hep G2 , Inibidores de PCSK9 , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Camundongos , Dieta Hiperlipídica , Apolipoproteínas E
2.
Org Lett ; 26(22): 4654-4659, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38804575

RESUMO

Herein, a gold-catalyzed cascade reaction of yne-enones with iminooxindoles has been developed through a cascade cycloisomerization/(3 + 2) annulation process. This approach provides a straightforward and efficient route for the synthesis of functionalized 3,2'-pyrrolidinyl-spirooxindoles in high reactivity and broad substrate scope with excellent cis-selectivity. Moreover, the subsequent functionalization of furan units allows for the diverse synthesis of spirooxindole derivatives, which have demonstrated good antitumoral activity.

3.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731489

RESUMO

Gallic acid (GA) is a type of polyphenolic compound that can be found in a range of fruits, vegetables, and tea. Although it has been confirmed it improves non-alcoholic fatty liver disease (NAFLD), it is still unknown whether GA can improve the occurrence of NAFLD by increasing the low-density lipoprotein receptor (LDLR) accumulation and alleviating cholesterol metabolism disorders. Therefore, the present study explored the effect of GA on LDLR and its mechanism of action. The findings indicated that the increase in LDLR accumulation in HepG2 cells induced by GA was associated with the stimulation of the epidermal growth factor receptor-extracellular regulated protein kinase (EGFR-ERK1/2) signaling pathway. When the pathway was inhibited by EGFR mab cetuximab, it was observed that the activation of the EGFR-ERK1/2 signaling pathway induced by GA was also blocked. At the same time, the accumulation of LDLR protein and the uptake of LDL were also suppressed. Additionally, GA can also promote the accumulation of forkhead box O3 (FOXO3) and suppress the accumulation of hepatocyte nuclear factor-1α (HNF1α), leading to the inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) mRNA expression and protein accumulation. This ultimately results in increased LDLR protein accumulation and enhanced uptake of LDL in cells. In summary, the present study revealed the potential mechanism of GA's role in ameliorating NAFLD, with a view of providing a theoretical basis for the dietary supplementation of GA.


Assuntos
Ácido Gálico , Lipoproteínas LDL , Receptores de LDL , Humanos , Ácido Gálico/farmacologia , Receptores de LDL/metabolismo , Células Hep G2 , Lipoproteínas LDL/metabolismo , Receptores ErbB/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética
4.
Int J Mol Sci ; 24(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37762316

RESUMO

Inhibiting the tyrosine kinase activity of epidermal growth factor receptor (EGFR) using small-molecule tyrosine kinase inhibitors (TKIs) or monoclonal antibodies is often ineffective in treating cancers harboring wild-type EGFR. Given the fact that EGFR possesses a kinase-independent pro-survival function, more effective inhibition of EGFR-mediated signals is therefore necessary. In this study, we investigated the effects of using a combination of low-dose nimotuzumab and theasinensin A to evaluate whether the inhibitory effect of nimotuzumab on NCI-H441 cancer cells was enhanced. Here, theasinensin A, a novel epigallocatechin-3-gallate (EGCG) derivative, was identified and its potent anticancer activity against wild-type EGFR NSCLC was demonstrated in vitro; the anticancer activity was induced through degradation of EGFR. Mechanistic studies further revealed that theasinensin A bound directly to the EGFR extracellular domain, which decreased interaction with its ligand EGF in combination with nimotuzumab. Theasinensin A significantly promoted EGFR degradation and repressed downstream survival pathways in combination with nimotuzumab. Meanwhile, treatment with theasinensin A and nimotuzumab prevented xenograft growth, whereas the single agents had limited effect. Thus, the combination therapy of theasinensin A with nimotuzumab is a powerful candidate for treatment of wild-type EGFR cancers.

5.
BMC Pharmacol Toxicol ; 24(1): 29, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170144

RESUMO

BACKGROUND: First-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as erlotinib, have been shown to target tumors with L858R (exon 21) and exon 19 deletions, resulting in significant clinical benefits. However, acquired resistance often occurs due to EGFR mutations. Therefore, novel therapeutic strategies for treatment of patients with EGFR-positive tumors are needed. Berberine (BBR) is an active alkaloid extracted from pharmaceutical plants such as Coptis chinensis. Berberine has been shown to significantly inhibit EGFR activity and mediate anticancer effects in multiple preclinical studies. We investigated whether combining BBR with erlotinib could augment erlotinib-induced cell growth inhibition of EGFR-positive cells in a mouse xenograft model. METHODS: We examined the antitumor activities and potential mechanisms of erlotinib in combination with berberine in vitro and in vivo using the MTT assay, immunoblotting, flow cytometry, and tumor xenograft models. RESULTS: In vitro studies with A431 cells showed that synergistic cell growth inhibition by the combination of BBR and erlotinib was associated with significantly greater inhibition of pEGFR and pAKT, and inhibition of cyclin D and Bcl-2 expression compared to that observed in response to BBR or erlotinib alone. The efficacy of the combination treatment was also investigated in nude mice. Consistent with the in vitro results, BBR plus erlotinib significantly reduced tumor growth. CONCLUSION: Our data supported use of BBR in combination with erlotinib as a novel strategy for treatment of patients with EGFR positive tumors.


Assuntos
Berberina , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Berberina/farmacologia , Berberina/uso terapêutico , Camundongos Nus , Receptores ErbB , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Mutação
6.
Biomed Pharmacother ; 161: 114575, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36963358

RESUMO

The tumor necrosis factor alpha (TNF-α)-TNF-α receptor (TNFR) interaction plays a central role in the pathogenesis of various autoimmune diseases, particularly rheumatoid arthritis, and is therefore considered a key target for drug discovery. However, natural compounds that can specifically block the TNF-α-TNFR interaction are rarely reported. (-)-Epigallocatechin-3-gallate (EGCG) is the most active, abundant, and thoroughly investigated polyphenolic compound in green tea. However, the molecular mechanism by which EGCG ameliorates autoimmune arthritis remains to be elucidated. In the present study, we found that EGCG can directly bind to TNF-α, TNFR1, and TNFR2 with similar µM affinity and disrupt the interactions between TNF-α and TNFR1 and TNFR2, which inhibits TNF-α-induced L929 cell death, blocks TNF-α-induced NF-κB activation in 293-TNF-α response cell line, and eventually leads to inhibition of TNF-α-induced NF-κB signaling pathway in HFLS and MH7A cells. Thus, regular consumption of EGCG in green tea may represent a potential therapeutic agent for the treatment of TNF-α-associated diseases.


Assuntos
Catequina , NF-kappa B , Humanos , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Células Cultivadas , Transdução de Sinais , Catequina/farmacologia , Chá , Fibroblastos/metabolismo
7.
Skin Res Technol ; 29(3): e13303, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36973992

RESUMO

BACKGROUND: Skin photoaging is the damage caused by excessive exposure to ultraviolet (UV) irradiation. We investigated the effect of adenosine triphosphate (ATP) supplementation on UVB-induced photoaging in HaCaT cells and its potential molecular mechanism. MATERIALS AND METHODS: The toxicity of ATP on HaCaT cells was examined by the MTT assay. The effects of ATP supplementation on the viability and apoptosis of HaCaT cells were determined by crystal-violet staining and flow cytometry, respectively. Cellular and mitochondrial ROS were stained using fluorescent dyes. Expression of Bax, B-cell lymphoma (Bcl)-2, sirtuin (SIRT)3, and superoxide dismutase (SOD)2 was measured via western blotting. RESULTS: ATP (1, 2 mM) exerted no toxic effect on the normal growth of HaCaT cells. UVB irradiation caused the apoptosis of HaCaT cells, and ATP supplementation inhibited the apoptosis induced by UVB significantly, as verified by expression of Bax and Bcl-2. UVB exposure resulted in accumulation of cellular and mitochondrial reactive oxygen species (ROS), but ATP supplementation suppressed these increases. Expression of SIRT3 and SOD2 was decreased upon exposure to UVB irradiation but, under ATP supplementation, expression of SIRT3 and SOD2 was reversed, which was consistent with the reduction in ROS level observed in ATP-treated HaCaT cells after exposure to UVB irradiation. CONCLUSIONS: ATP supplementation can suppress UVB irradiation-induced photoaging in HaCaT cells via upregulation of expression of SIRT3 and SOD2.


Assuntos
Sirtuína 3 , Envelhecimento da Pele , Humanos , Regulação para Cima , Espécies Reativas de Oxigênio , Células HaCaT/metabolismo , Sirtuína 3/metabolismo , Sirtuína 3/farmacologia , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia , Apoptose/efeitos da radiação , Queratinócitos/metabolismo , Suplementos Nutricionais , Raios Ultravioleta/efeitos adversos
8.
Food Funct ; 14(7): 3269-3278, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36916513

RESUMO

Increasing low-density lipoprotein receptor (LDLR) protein levels represents a key strategy for the prevention and treatment. Berberine can reportedly alleviate non-alcoholic fatty liver disease (NAFLD) by increasing the LDLR expression in an ERK1/2 signaling-dependent manner of NAFLD. Studies have shown that caffeine can inhibit fat deposition in the livers of mice; however, caffeine has not been reported to alleviate NAFLD by augmenting the LDLR expression via targeting EGFR. Here, an MTT assay, western blotting, RT-qPCR, immunohistochemistry, and surface plasmon resonance (SPR) analysis were used to investigate the role of caffeine in low-density lipoprotein cholesterol (LDL-C) clearance both in vitro and in vivo. In vitro, we found that caffeine could activate the EGFR-ERK1/2 signaling pathway in HepG2 cells, leading to increased LDLR mRNA and protein expression, and this effect could be inhibited by cetuximab. The SPR assay results have indicated that caffeine may increase the LDLR expression by directly binding to the EGFR extracellular domain and activating the EGFR-ERK1/2 signaling pathway. In vivo, caffeine markedly improved fatty liver and related blood indices in ApoE KO mice with high-fat-diet-induced NAFLD. Consistent with our in vitro results, we found that caffeine could also activate EGFR-ERK1/2 signaling and promote the LDLR expression in ApoE KO mice. In summary, caffeine can enhance the LDLR expression by directly binding to EGFR and activating the EGFR-ERK1/2 signaling pathway. EGFR signaling may represent a novel target for the prevention and treatment of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Cafeína/farmacologia , Cafeína/metabolismo , Fígado/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , LDL-Colesterol/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Apolipoproteínas E/genética , Camundongos Endogâmicos C57BL
9.
Molecules ; 27(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080195

RESUMO

Tea contains high levels of the compound epigallocatechin gallate (EGCG). It is considered an important functional component in tea and has anti-cancer, antioxidant, and anti-inflammatory effects. The eight phenolic hydroxyl groups in EGCG's chemical structure are the basis for EGCG's multiple biological effects. At the same time, it also leads to poor chemical stability, rendering EGCG prone to oxidation and isomerization reactions that change its original structure and biological activity. Learning how to maintain the activity of EGCG has become an important goal in understanding the biological activity of EGCG and the research and development of tea-related products. Metal-organic frameworks (MOFs) are porous materials with a three-dimensional network structure that are composed of inorganic metals or metal clusters together with organic complexes. MOFs exploit the porous nature of the material itself. When a drug is an appropriate size, it can be wrapped into the pores by physical or chemical methods; this allows the drug to be released slowly, and MOFs can also reduce drug toxicity. In this study, we used MOF Zn(BTC)4 materials to load EGCG and investigated the sustained release effect of EGCG@MOF Zn(BTC)4 and the biological effects on wound healing in a diabetic mouse model.


Assuntos
Catequina , Diabetes Mellitus , Animais , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Camundongos , Chá/química , Cicatrização , Zinco
10.
Bioorg Chem ; 128: 106084, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35970070

RESUMO

Aberrant activation of epidermal growth factor receptor (EGFR) plays a pivotal role in cancer initiation and progression and has gained attention as an anticancer drug target. EGFR monoclonal antibodies have been canonically used in non-small cell lung cancer (NSCLC) treatment. However, a basal level of ligand-independent EGFR signaling pro-survival properties limit the clinical efficacy of EGFR monoclonal antibodies. Therefore, targeting EGFR by inducing degraders is a promising approach towards improving therapeutic efficacy and augmenting the effect of nimotuzumab. Here we describe rational discovery of OTP-3, an oxidized (-)-Epigallocatechin gallate (EGCG) derivative that elicits potent anticancer activity in EGFR wild type NSCLC. Mechanistic studies disclosed that OTP-3 directly binds to EGFR extracellular domain decreases EGF and EGFR binding affinities by combination with nimotuzumab. Molecular docking studies revealed that OTP-3-EGFR is a very stable complex. Further analyses showed that nimotuzumab combined with OTP-3 resulted in significantly promoted EGFR degradation and repressed downstream survival pathways. Accordingly, OTP-3 combined with nimotuzumab significantly inhibits tumor growth through degrading EGFR in vivo. Thus, OTP-3 can also serve as an effective therapeutic agent in NSCLC where it can augment the effects of nimotuzumab, a valuable property for combination agents.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Receptores ErbB , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Simulação de Acoplamento Molecular , Polifenóis , Chá
11.
Chem Biol Interact ; 365: 110084, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35970427

RESUMO

Non-small cell lung cancer (NSCLC) is one of the most general malignant tumors. The overexpression of epidermal growth factor receptor (EGFR) is a common marker in NSCLC, and it plays an important role in the proliferation, invasion, and metastasis of cancer cells. At present, drugs developed with EGFR as a target suffer from drug resistance, so it is necessary to study new compounds for the treatment of NSCLC. The active substance in green tea is EGCG, which has anti-cancer effects. In this study, we synthesized dimeric-(-)-epigallocatechin-3-gallate (prodelphinidin B-4-3,3‴-di-O-gallate, PBOG), and explored the effect of PBOG on lung cancer cells. PBOG can inhibit the proliferation and migration of NCI-H1975 cells, promote cell apoptosis, and inhibit cell cycle progression. In addition, PBOG can bind to the EGFR ectodomain protein and change the secondary structure of the protein. At the same time, PBOG decreases the expression of EGFR and downstream protein phosphorylation. Animal experiments confirmed that PBOG can inhibit tumor growth by inhibiting EGFR phosphorylation. Collectively, our study results show that PBOG may induce a decrease in intracellular phosphorylated EGFR expression by binding to the EGFR ectodomain protein, thereby inducing apoptosis and inhibiting cell cycle progression, thus providing a new strategy to treat lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Apoptose , Carcinoma Pulmonar de Células não Pequenas/patologia , Catequina/análogos & derivados , Linhagem Celular Tumoral , Proliferação de Células , Receptores ErbB/metabolismo , Neoplasias Pulmonares/patologia , Transdução de Sinais
12.
Food Funct ; 13(13): 7020-7028, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35723202

RESUMO

Chinese medicinal and edible plants such as Panax notoginseng and ginseng are widely used for the treatment of atherosclerosis (AS). AS is the main pathological basis of cardiac-cerebral vascular disease, which seriously threatens human health and quality of life. Low-density lipoprotein (LDL) is the main pathogenic factor of AS. The LDL receptor (LDLR) is an important protein that functions to mediate the uptake and degradation of plasma LDL. Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) can mediate the internalization and degradation of LDLR. So, increasing the LDLR level by inhibiting PCSK9 is an important means of prevention and treatment of AS. In this study, by combining interaction technology (surface plasmon resonance, SPR) of small molecule compounds with membrane receptor proteins, cell experiments, and in vivo experiments, it is proved for the first time that 20(S)-protopanaxadiol (PPD), as a hydrolytic product of Panax notoginseng saponins in the intestinal tract, can bind to the extracellular domain of LDLR and inhibit the role of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in mediating LDLR degradation. The results showed that PPD significantly reduced aortic plaques and hepatic steatosis in HFD-fed ApoE KO mice. LDLR protein levels were elevated in the liver tissues isolated from PPD-treated HFD-fed ApoE KO mice and PPD-treated HepG2 cells. Our findings demonstrated that PPD significantly increased LDLR levels and reduced AS in the HFD-fed ApoE KO mice on account of LDLR degradation being inhibited by PPD inhibiting the interaction between PCSK9 and LDLR.


Assuntos
Aterosclerose , Pró-Proteína Convertase 9 , Animais , Apolipoproteínas E/genética , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Aterosclerose/metabolismo , Células Hep G2 , Humanos , Camundongos , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Sapogeninas , Subtilisinas
13.
Int J Biol Macromol ; 213: 328-338, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35594938

RESUMO

To explore the active polysaccharides from Dendrobium devonianum, a novel O-acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)-ß-d-Manp-(1 â†’ (71.4%) residue with internal →4)-2-O-acetyl-ß-d-Manp-(1 â†’ (14.2%), →4)-3-O-acetyl-ß-d-Manp-(1 â†’ (7.1%), and non-reducing end ß-d-Manp-(1 â†’ (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF-α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials.


Assuntos
Dendrobium , Citocinas , Dendrobium/química , Mananas/farmacologia , Polímeros , Polissacarídeos/química
14.
Biomed Pharmacother ; 151: 113140, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35605290

RESUMO

Excessive osteoclast differentiation and activation are closely associated with the development and progression of osteoporosis. Natural plant-derived compounds that can inhibit osteoclastogenesis are an efficient strategy for the prevention and treatment of osteoporosis. Tereticornate A (TA) is a natural terpene ester compound extracted from the leaves and branches of Eucalyptus gracilis, with antiviral, antibacterial, and anti-inflammatory activities. However, the effect of TA on osteoclastogenesis and the underlying molecular mechanism remain unclear. Based on the key role of the NF-κB pathway in the regulation of osteoclastogenesis and the observation that TA exhibits an anti-inflammatory effect by inhibiting NF-κB activity, we speculated that TA could exert anti-osteoclastogenesis activity. Herein, TA could inhibit the RANKL-induced osteoclast differentiation and formation of F-actin rings in RAW 264.7 cells. Mechanistically, TA downregulated the expression of c-Src and TRAF6, and also suppressed the RANKL-stimulated canonical RANK signaling pathways, including AKT, MAPK (p38, JNK, and ERK), and NF-κB; ultimately, downregulating the expression of NFATc1 and c-Fos, the key transcriptional factors required for the expression of genes (e.g., TRAP, cathepsin K, ß-Integrin, MMP-9, ATP6V0D2, and DC-STAMP) that govern osteoclastogenesis. Our findings demonstrated that TA could effectively inhibit RANKL-induced osteoclastogenesis via the downregulation of c-Src and TRAF6 and the inhibition of RANK signaling pathways. Thus, TA could serve as a novel osteoclastogenesis inhibitor and might have beneficial effects on bone health.


Assuntos
Conservadores da Densidade Óssea , Reabsorção Óssea , Óleo de Eucalipto , Osteoclastos , Animais , Conservadores da Densidade Óssea/farmacologia , Reabsorção Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo , Óleo de Eucalipto/farmacologia , Genes src/fisiologia , Camundongos , Monoterpenos/farmacologia , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Proteínas Tirosina Quinases/metabolismo , Ligante RANK/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fator 6 Associado a Receptor de TNF/metabolismo
15.
Front Immunol ; 13: 853165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222445

RESUMO

Tumor necrosis factor (TNF)-stimulated nuclear factor-kappa B (NF-κB) signaling plays very crucial roles in cancer development and progression, and represents a potential target for drug discovery. Roburic acid is a newly discovered tetracyclic triterpene acid isolated from oak galls and exhibits anti-inflammatory activity. However, whether roburic acid exerts antitumor effects through inhibition of TNF-induced NF-κB signaling remains unknown. Here, we demonstrated that roburic acid bound directly to TNF with high affinity (KD = 7.066 µM), blocked the interaction between TNF and its receptor (TNF-R1), and significantly inhibited TNF-induced NF-κB activation. Roburic acid exhibited antitumor activity in numerous cancer cells and could effectively induce G0/G1 cell cycle arrest and apoptosis in colorectal cancer cells. Importantly, roburic acid inhibited the TNF-induced phosphorylation of IKKα/ß, IκBα, and p65, degradation of IκBα, nuclear translocation of p65, and NF-κB-target gene expression, including that of XIAP, Mcl-1, and Survivin, in colorectal cancer cells. Moreover, roburic acid suppressed tumor growth by blocking NF-κB signaling in a xenograft nude mouse model of colorectal cancer. Taken together, our findings showed that roburic acid directly binds to TNF with high affinity, thereby disrupting its interaction with TNF-R1 and leading to the inhibition of the NF-κB signaling pathway, both in vitro and in vivo. The results indicated that roburic acid is a novel TNF-targeting therapeutics agent in colorectal cancer as well as other cancer types.


Assuntos
Neoplasias Colorretais , NF-kappa B , Animais , Neoplasias Colorretais/tratamento farmacológico , Humanos , Camundongos , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
16.
Bioorg Chem ; 121: 105585, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35183859

RESUMO

Overexpression of human epidermal growth factor receptor (EGFR) plays an important role in several signaling pathways inside and outside the cell, especially in the processes of cell proliferation, differentiation, and death in various cancers. Due to the complexity of the structure and function of EGFR, research on the fluorescence visualization of EGFR protein visualization has proved challenging. One possible strategy for designing a receptor-targeting fluorescent probe with a switching mechanism is to introduce an environment-sensitive fluorophore into the drug ligand. Based on this strategic molecular design, we introduced two environment-sensitive small molecular fluorophores, dansyl chloride (DNS) and nitrobenzoxadiazole (NBD), to replace the morpholine group of gefitinib, achieving a series of fluorescent molecular probes bearing a switching mechanism. The GN probes exhibited prominent environment sensitivity, suggesting good performance as turn-on EGFR-targeting fluorescent ligands. The representative probe GN3 specifically responded to tumor cells overexpressing EGFR, which was validated with live-cell fluorescence imaging and in vivo xenograft tumor imaging. Ligand-induced EGFR phosphorylation in A431 cells was considerably inhibited by probe GN3, demonstrating that this probe still functions as an EGFR inhibitor. Owing to the turn-on response of GN3 to EGFR in tumor cells, and the competitive replacement behavior to the EGFR inhibitor gefitinib, these probes have the potential to be used for fluorescence imaging of cells overexpressing EGFR.


Assuntos
Receptores ErbB , Corantes Fluorescentes , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Gefitinibe/farmacologia , Humanos , Ligantes , Inibidores de Proteínas Quinases/farmacologia
17.
Nat Prod Res ; 36(15): 3951-3956, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33749420

RESUMO

Dendrocandins are characteristic chemical structures of D. officinale and have strong physiological bioactivities. In this study, a dendrocandin analogue (1) has been prepared by total synthesis (9 steps, 12.6% overall yield) in which coupling reaction and Wittig reaction as the key steps. Compound 1 was also evaluated for its anticancer activity in vitro against six human cancer cells (MCF-7, A549, A431, SW480, HepG-2 and HL-60) using MTT assays. Compound 1 showed potent cytotoxicity, with the IC50 value 16.27 ± 0.26 µM. The expression levels of apoptotic proteins indicated that compound 1 can up-regulate the expression of apoptotic proteins, leading to apoptosis. This compound suggested that it's potential as anticancer agent for further development.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
18.
Artigo em Inglês | MEDLINE | ID: mdl-34499597

RESUMO

A Gram-reaction-negative, yellow-pigmented, non-spore-forming rod, aerobic, motile bacterium, designated SJY3T, was isolated from soil samples collected from a Pu-erh tea cellar in Bolian Pu-erh tea estate Co. Ltd. in Pu'er city, Yunnan, south-west China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Massilia. The closest phylogenetic relative was Massilia arenae CICC 24458T (99.5 %), followed by M. timonae CCUG45783T (97.9 %), M. oculi CCUG43427AT (97.8 %), and M. aurea DSM 18055T (97.8 %). The major fatty acids were C16 : 0 and C16 : 1 ω7c and/or C16 : 1 ω6c. The major respiratory quinone was ubiquinone Q-8 and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. Genome sequencing revealed a genome size of 5.97 M bp and a G+C content of 65.4 mol%. Pairwise determined whole genome average nucleotide identity (gANI) values and digital DNA-DNA hybridization (dDDH) values were all below the threshold. Although the 16S rRNA gene similarity of stain SJY3T and Massilia arenae CICC 24458T was more than 99 %, the gANI, dDDH values and genomic tree clearly indicated that they were not of the same species. In summary, strain SJY3T represents a new species, for which we propose the name Massilia puerhi sp. nov. with the type strain SJY3T (=CGMCC 1.17158T=KCTC 82193T).


Assuntos
Oxalobacteraceae/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oxalobacteraceae/isolamento & purificação , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Chá , Ubiquinona/química
19.
Molecules ; 26(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299635

RESUMO

Lung cancer is one of the most commonly occurring cancer mortality worldwide. The epidermal growth factor receptor (EGFR) plays an important role in cellular functions and has become the new promising target. Natural products and their derivatives with various structures, unique biological activities, and specific selectivity have served as lead compounds for EGFR. D-glucose and EGCG were used as starting materials. A series of glucoside derivatives of EGCG (7-12) were synthesized and evaluated for their in vitro anticancer activity against five human cancer cell lines, including HL-60, SMMC-7721, A-549, MCF-7, and SW480. In addition, we investigated the structure-activity relationship and physicochemical property-activity relationship of EGCG derivatives. Compounds 11 and 12 showed better growth inhibition than others in four cancer cell lines (HL-60, SMMC-7721, A-549, and MCF), with IC50 values in the range of 22.90-37.87 µM. Compounds 11 and 12 decreased phosphorylation of EGFR and downstream signaling protein, which also have more hydrophobic interactions than EGCG by docking study. The most active compounds 11 and 12, both having perbutyrylated glucose residue, we found that perbutyrylation of the glucose residue leads to increased cytotoxic activity and suggested that their potential as anticancer agents for further development.


Assuntos
Antineoplásicos , Catequina/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Citotoxinas , Glucose , Simulação de Acoplamento Molecular , Proteínas de Neoplasias , Neoplasias , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Catequina/síntese química , Catequina/química , Catequina/farmacologia , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Receptores ErbB/biossíntese , Receptores ErbB/química , Glucose/análogos & derivados , Glucose/síntese química , Glucose/química , Glucose/farmacologia , Células HL-60 , Humanos , Células MCF-7 , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/química , Neoplasias/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos
20.
J Cancer ; 12(13): 3900-3908, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093797

RESUMO

Non-small cell lung cancer (NSCLC) harboring activating EGFR mutations were initially treated by first-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs), unfortunately, the efficacy of these drugs is limited, mostly frequent due to T790M mutation. Although osimertinib has been approved to treat patients with T790M-positive NSCLC, the majority of patients will develop C797S mutation and suffer diseases again. Therefore, more novel therapeutic strategies for T790M mutation-positive NSCLC are urgently required. We hypothesized that wighteone, a natural compound isolated from plant derivatives, has antitumor effects against NSCLC with T790M mutation. In this study, we created a Ba/F3 cell line harboring EGFR L858R/T790M mutation (Ba/F3 EGFR L858R/T790M cell line), and then used this cell line and a human NSCLC cell line with EGFR L858R/T790M mutation (NCI-H1975) to investigate the effects and mechanism of wighteone. The results showed that wighteone inhibited cell proliferation, suppressed EGFR signaling pathway, caused cell cycle redistribution and induced cell apoptosis. Our studies suggest that wighteone may provide a novel potential therapeutic strategy for NSCLC patients with T790M mutation.

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