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1.
Molecules ; 29(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731489

ABSTRACT

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.


Subject(s)
Gallic Acid , Lipoproteins, LDL , Receptors, LDL , Humans , Gallic Acid/pharmacology , Receptors, LDL/metabolism , Hep G2 Cells , Lipoproteins, LDL/metabolism , ErbB Receptors/metabolism , MAP Kinase Signaling System/drug effects , Signal Transduction/drug effects , Proprotein Convertase 9/metabolism , Proprotein Convertase 9/genetics
2.
Phys Chem Chem Phys ; 26(12): 9517-9523, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38450673

ABSTRACT

3,4-Bis(3-nitrofurazan-4-yl)furoxan (DNTF) is a novel energetic material with an excellent performance and has attracted considerable attention. Motivated by recent theories and experiments, we had carried out experimental and theoretical studies on the high-pressure responses of vibrational characteristics, in conjunction with structural and electronic characteristics. It is found that all observed infrared spectra peaks seem to shift towards higher frequencies. And the peaks attributed to N-Oc (coordinated oxygen atom) stretching vibrations become broader due to the decrease of lattice constants and the free region of DNTF crystals with the increase of pressure, where the a-direction is more sensitive to pressure. In addition, the non-covalent interaction between adjacent DNTF molecules in the same layer changes from the van der Waals interaction to the steric effect with the increase of pressure, and that between layers also changes from the van der Waals interaction to the π-π stacking interaction. More importantly, these results highlight that the increase of pressure may lead to the stability decrease and impact the sensitivity increase of DNTF. This study can deepen the understanding of the energetic material DNTF under high pressure and is of great significance for blasting and detonation applications of DNTF.

3.
Molecules ; 29(3)2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38338332

ABSTRACT

In total, three related substances (RS) associated with sotalol hydrochloride (STHCl) were herein identified with a novel gradient high-performance liquid chromatography (HPLC) protocol. Further characterization of these substances was then performed via liquid chromatography-mass spectroscopy (LC-MS/MS) and nuclear magnetic resonance (NMR) approaches. For these analyses, commercial STHCl samples were used for quantitative HPLC studies and the degradation of STHCl under acidic (1M HCl), alkaline (1M NaOH), oxidative (30% H2O2), photolytic (4500 Lx), and thermal stress conditions (100 °C) was assessed. This approach revealed this drug to be resistant to acidic, alkaline, and high-temperature conditions, whereas it was susceptible to light and oxidation as confirmed through long-term experiments. The putative mechanisms governing RS formation were also explored, revealing that RS3 was derived from the manufacturing process, whereas RS2 was generated via oxidation and RS1 was generated in response to light exposure. The cytotoxicity of these RS compounds was then assessed using MTT assays and acute toxicity test. Overall, this study provides details regarding the characterization, isolation, quantification, and toxicological evaluation of STHCl and associated RS compounds together with details regarding the precise, specific, and reliable novel HPLC technique, thus providing the requisite information necessary to ensure STHCl purity and safety.


Subject(s)
Sotalol , Tandem Mass Spectrometry , Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Sotalol/pharmacology , Tandem Mass Spectrometry/methods , Hydrogen Peroxide , Liquid Chromatography-Mass Spectrometry , Drug Stability , Hydrolysis , Oxidation-Reduction , Photolysis
4.
Entropy (Basel) ; 25(12)2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38136468

ABSTRACT

Point cloud completion aims to generate high-resolution point clouds using incomplete point clouds as input and is the foundational task for many 3D visual applications. However, most existing methods suffer from issues related to rough localized structures. In this paper, we attribute these problems to the lack of attention to local details in the global optimization methods used for the task. Thus, we propose a new model, called PA-NET, to guide the network to pay more attention to local structures. Specifically, we first use textual embedding to assist in training a robust point assignment network, enabling the transformation of global optimization into the co-optimization of local and global aspects. Then, we design a novel plug-in module using the assignment network and introduce a new loss function to guide the network's attention towards local structures. Numerous experiments were conducted, and the quantitative results demonstrate that our method achieves novel performance on different datasets. Additionally, the visualization results show that our method efficiently resolves the issue of poor local structures in the generated point cloud.

5.
Molecules ; 28(20)2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37894597

ABSTRACT

The phytochemical investigation of Veratrum mengtzeanum Loes. roots resulted in the isolation and characterization of two novel, namely Mengtzeanines A (1), Mengtzeanines B (2), and eight known steroidal alkaloids (3-10). Their structural properties were assessed though extensive spectroscopic techniques. All constituents 1-10 were analyzed for suppression of NO formation in LPS-induced RAW264.7 macrophages. Among them, constituent 6 (Verazine) showed inhibition against LPS-induced NO production (IC50 = 20.41 µM). Additionally, compound 6 could inhibit the secretion of IL1ß, IL6, and TNFα, and downregulate the productions of iNOS and COX2 in LPS-induced RAW264.7 macrophages. Further experiments revealed that 6 exhibited a potent anti-inflammatory level in LPS-stimulated RAW264.7 macrophages via inhibiting NF-κB, and triggering of Keap1/Nrf2/HO-1 axis, implying that compound 6 may be a promising candidate for treating inflammatory disorders.


Subject(s)
Alkaloids , Veratrum , Animals , Mice , Veratrum/chemistry , Kelch-Like ECH-Associated Protein 1 , Lipopolysaccharides/pharmacology , NF-E2-Related Factor 2/metabolism , Anti-Inflammatory Agents/pharmacology , Alkaloids/pharmacology , NF-kappa B/metabolism , RAW 264.7 Cells , Nitric Oxide/metabolism
6.
Int J Mol Sci ; 24(18)2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37762316

ABSTRACT

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.

7.
BMC Pharmacol Toxicol ; 24(1): 29, 2023 05 11.
Article in English | MEDLINE | ID: mdl-37170144

ABSTRACT

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.


Subject(s)
Berberine , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Animals , Mice , Erlotinib Hydrochloride/pharmacology , Erlotinib Hydrochloride/therapeutic use , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/drug therapy , Berberine/pharmacology , Berberine/therapeutic use , Mice, Nude , ErbB Receptors , Cell Line, Tumor , Xenograft Model Antitumor Assays , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Drug Resistance, Neoplasm , Mutation
8.
Front Pharmacol ; 14: 1128699, 2023.
Article in English | MEDLINE | ID: mdl-37124197

ABSTRACT

Hesperetin is a natural flavonoid with many biological activities. In view of hyperuricemia treatment, the effects of hesperetin in vivo and in vitro, and the underlying mechanisms, were explored. Hyperuricemia models induced by yeast extract (YE) or potassium oxonate (PO) in mice were created, as were models based on hypoxanthine and xanthine oxidase (XOD) in L-O2 cells and sodium urate in HEK293T cells. Serum level of uric acid (UA), creatinine (CRE), and urea nitrogen (BUN) were reduced significantly after hesperetin treatment in vivo. Hesperetin provided hepatoprotective effects and inhibited xanthine oxidase activity markedly, altered the level of malondialdehyde (MDA), glutathione peroxidase (GSH-PX) and catalase (CAT), downregulated the XOD protein expression, toll-like receptor (TLR)4, nucleotide binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, interleukin-18 (IL-18), upregulated forkhead box O3a (FOXO3a), manganese superoxide dismutase (MnSOD) in a uric acid-synthesis model in mice. Protein expression of organic anion transporter 1 (OAT1), OAT3, organic cationic transporter 1 (OCT1), and OCT2 was upregulated by hesperetin intervention in a uric acid excretion model in mice. Our results proposal that hesperetin exerts a uric acid-lowering effect through inhibiting xanthine oxidase activity and protein expression, intervening in the TLR4-NLRP3 inflammasome signaling pathway, and up-regulating expression of FOXO3a, MnSOD, OAT1, OAT3, OCT1, and OCT2 proteins. Thus, hesperetin could be a promising therapeutic agent against hyperuricemia.

9.
Phytomedicine ; 114: 154798, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37031639

ABSTRACT

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD), peculiarly nonalcoholic steatohepatitis (NASH), has become the main cause of liver transplantation and liver-related death. However, the US Food and Drug Administration has not approved a specific medication for treating NASH. Neferine (NEF), a natural bisbenzylisoquinoline alkaloid separated from the traditional Chinese medicine Nelumbinis plumula, has a variety of pharmacological properties, especially on metabolic diseases. Nevertheless, the anti-NASH effect and mechanisms of NEF remain unclear. PURPOSE: This study aimed to investigate the amelioration of NEF on NASH and the potential mechanisms. STUDY DESIGN: HepG2 cells, hepatic stellate cells (HSCs) and high-fat diet (HFD)+carbon tetrachloride (CCl4) induced C57BL/6 mice were used to observe the effect of NEF against NASH and investigate the engaged mechanism. METHODS: HSCs and HepG2 cells stimulated by oleic acid (OA) were treated with NEF. C57BL/6 mice were fed with HFD+CCl4 to induce NASH mouse model and treated with or without NEF (5 mg/kg or 10 mg/kg, once daily, i.p) for 4 weeks. RESULTS: NEF significantly attenuated the accumulation of lipid droplets, intracellular triglyceride (TG) levels and hepatocytes apoptosis in OA-exposed HepG2 cells. NEF not only enhanced the AMPK and ACC phosphorylation in OA-stimulated HepG2 cells, but also reduced inflammatory response and fibrosis in lipopolysaccharide (LPS)-stimulated HepG2 and in LX-2, respectively. In HFD+CCl4-induced NASH mice, pathological staining confirmed NEF treatment mitigated hepatic lipid deposition, inflammatory cell infiltration as well as hepatic fibrosis. Furthermore, the liver weight, serum and hepatic TG and total cholesterol (TC) and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were decreased compared with the model group. HFD+CCl4 also induced the upregulation of specific proteins and genes associated to inflammation (ILs, TNF-α, NLRP3, ASC, CCL2 and CXCL10) and hepatic fibrosis (collagens, α-SMA, TGF-ß and TIPM1), which were also suppressed by NEF treatment. CONCLUSION: Our results demonstrated that NEF played a protective role in hepatic steatosis via the regulation of AMPK pathways, which may serve as an attractive candidate for a potential novel strategy on prevention and treatment of NASH.


Subject(s)
Benzylisoquinolines , Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , AMP-Activated Protein Kinases/metabolism , Mice, Inbred C57BL , Liver , Benzylisoquinolines/pharmacology , Liver Cirrhosis/drug therapy , Diet, High-Fat
10.
Biomed Pharmacother ; 161: 114575, 2023 May.
Article in English | MEDLINE | ID: mdl-36963358

ABSTRACT

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.


Subject(s)
Catechin , NF-kappa B , Humans , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , Cells, Cultured , Signal Transduction , Catechin/pharmacology , Tea , Fibroblasts/metabolism
11.
Food Funct ; 14(7): 3269-3278, 2023 Apr 03.
Article in English | MEDLINE | ID: mdl-36916513

ABSTRACT

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.


Subject(s)
Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Caffeine/pharmacology , Caffeine/metabolism , Liver/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism , Cholesterol, LDL/metabolism , ErbB Receptors/genetics , ErbB Receptors/metabolism , Apolipoproteins E/genetics , Mice, Inbred C57BL
12.
Skin Res Technol ; 29(3): e13303, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36973992

ABSTRACT

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.


Subject(s)
Sirtuin 3 , Skin Aging , Humans , Up-Regulation , Reactive Oxygen Species , HaCaT Cells/metabolism , Sirtuin 3/metabolism , Sirtuin 3/pharmacology , bcl-2-Associated X Protein/metabolism , bcl-2-Associated X Protein/pharmacology , Superoxide Dismutase/metabolism , Superoxide Dismutase/pharmacology , Apoptosis/radiation effects , Keratinocytes/metabolism , Dietary Supplements , Ultraviolet Rays/adverse effects
13.
Nanomaterials (Basel) ; 13(3)2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36770425

ABSTRACT

The crystal structure has a great influence on mechanical sensitivity and detonation performance of energetic materials. An efficient microfluidic platform was applied for size, morphology, and crystallinity controllable preparation of ultrafine HMX. The microfluidic platform has good mixing performance, quick response, and less reagent consumption. The ultrafine γ-HMX was first prepared at room temperature by microfluidic strategy, and the crystal type can be controlled accurately by adjusting the process parameters. With the increase in flow ratio, the particle size decreases gradually, and the crystal type changed from ß-HMX to γ-HMX. Thermal behavior of ultrafine HMX shows that γ→δ is easier than ß→δ, and the phase stability of HMX is ß > γ > δ. Furthermore, the ultrafine ß-HMX has higher thermal stability and energy release efficiency than that of raw HMX. The ultrafine HMX prepared by microfluidic not only has uniform morphology and narrow particle size distribution, but also exhibits high density and low sensitivity. This study provides a safe, facile, and efficient way of controlling particle size, morphology, and crystallinity of ultrafine HMX.

14.
Molecules ; 27(17)2022 Aug 25.
Article in English | MEDLINE | ID: mdl-36080195

ABSTRACT

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.


Subject(s)
Catechin , Diabetes Mellitus , Animals , Catechin/analogs & derivatives , Catechin/chemistry , Catechin/pharmacology , Mice , Tea/chemistry , Wound Healing , Zinc
15.
Bioorg Chem ; 128: 106084, 2022 11.
Article in English | MEDLINE | ID: mdl-35970070

ABSTRACT

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.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Antibodies, Monoclonal, Humanized/pharmacology , Antibodies, Monoclonal, Humanized/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , ErbB Receptors , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Molecular Docking Simulation , Polyphenols , Tea
16.
Chem Biol Interact ; 365: 110084, 2022 Sep 25.
Article in English | MEDLINE | ID: mdl-35970427

ABSTRACT

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.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Animals , Apoptosis , Carcinoma, Non-Small-Cell Lung/pathology , Catechin/analogs & derivatives , Cell Line, Tumor , Cell Proliferation , ErbB Receptors/metabolism , Lung Neoplasms/pathology , Signal Transduction
17.
Food Funct ; 13(13): 7020-7028, 2022 Jul 04.
Article in English | MEDLINE | ID: mdl-35723202

ABSTRACT

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.


Subject(s)
Atherosclerosis , Proprotein Convertase 9 , Animals , Apolipoproteins E/genetics , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Atherosclerosis/metabolism , Hep G2 Cells , Humans , Mice , Proprotein Convertase 9/genetics , Proprotein Convertase 9/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism , Sapogenins , Subtilisins
18.
Adv Mater ; 34(32): e2203900, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35724969

ABSTRACT

Water electrolysis involves two parallel reactions, that is, oxygen evolution (OER) and hydrogen evolution (HER), in which sluggish OER is a significant limiting step that results in high energy consumption. Coupling the thermodynamically favorable electrooxidation of organic alternatives to value-added fine chemicals HER is a promising approach for the simultaneous cost-effective production of value-added chemicals and hydrogen. Here, a new coupling system for the green electrochemical synthesis of organic energetic materials (EMs) plus hydrogen production using single-atom catalysts is introduced. The catalysts are prepared by the facile galvanostatic deposition of ruthenium single atoms on the molybdenum selenide and reveal a low HER overpotential of 38.9 mV at -10 mA cm-2 in an alkaline medium. Importantly, the cell voltage of water electrolysis can be significantly reduced to only 1.35 V at a current of 10 mA cm-2 by coupling water splitting with the electrooxidation of 5-amino-1H-tetrazole to synthesize 5,5'-azotetrazolate energetic material. These materials are traditionally synthesized under harsh conditions involving a strong oxidizing agent, high-temperature conditions, and difficult separation of by-products. This study provides a green and efficient method of synthesizing organic EMs while simultaneously producing hydrogen.

19.
Biomed Pharmacother ; 151: 113140, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35605290

ABSTRACT

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.


Subject(s)
Bone Density Conservation Agents , Bone Resorption , Eucalyptus Oil , Osteoclasts , Animals , Bone Density Conservation Agents/pharmacology , Bone Resorption/metabolism , Cell Differentiation/drug effects , Down-Regulation , Eucalyptus Oil/pharmacology , Genes, src/physiology , Mice , Monoterpenes/pharmacology , NF-kappa B/metabolism , NFATC Transcription Factors/metabolism , Osteoclasts/drug effects , Osteoclasts/metabolism , Osteogenesis/drug effects , Osteoporosis/metabolism , Protein-Tyrosine Kinases/metabolism , RANK Ligand/metabolism , RAW 264.7 Cells , Signal Transduction/drug effects , TNF Receptor-Associated Factor 6/metabolism
20.
Int J Biol Macromol ; 213: 328-338, 2022 Jul 31.
Article in English | MEDLINE | ID: mdl-35594938

ABSTRACT

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.


Subject(s)
Dendrobium , Cytokines , Dendrobium/chemistry , Mannans/pharmacology , Polymers , Polysaccharides/chemistry
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