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Pancreatic ductal adenocarcinoma (PDAC) poses significant clinical challenges, often presenting as unresectable with limited biopsy options. Here, we show that circulating tumor cells (CTCs) offer a promising alternative, serving as a "liquid biopsy" that enables the generation of in vitro 3D models and highly aggressive in vivo models for functional and molecular studies in advanced PDAC. Within the retrieved CTC pool (median 65 CTCs/5 mL), we identify a subset (median content 8.9%) of CXCR4+ CTCs displaying heightened stemness and metabolic traits, reminiscent of circulating cancer stem cells. Through comprehensive analysis, we elucidate the importance of CTC-derived models for identifying potential targets and guiding treatment strategies. Screening of stemness-targeting compounds identified stearoyl-coenzyme A desaturase (SCD1) as a promising target for advanced PDAC. These results underscore the pivotal role of CTC-derived models in uncovering therapeutic avenues and ultimately advancing personalized care in PDAC.
Assuntos
Carcinoma Ductal Pancreático , Células Neoplásicas Circulantes , Neoplasias Pancreáticas , Medicina de Precisão , Humanos , Medicina de Precisão/métodos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Animais , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Camundongos , Feminino , Masculino , Estearoil-CoA Dessaturase/metabolismo , Estearoil-CoA Dessaturase/genética , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genéticaRESUMO
LHPP has been shown to be a new tumor suppressor, and has a tendency to be under-expressed in a variety of cancers. Oncolytic virotheray is a promising therapeutics for lung cancer in recent decade years. Here we successfully constructed a new recombinant oncolytic adenovirus GD55-LHPP and investigated the effect of GD55-LHPP on the growth of lung cancer cells in vitro and in vivo. The results showed that LHPP had lower expression in either lung cancer cells or clinical lung cancer tissues compared with normal cells or tissues, and GD55-LHPP effectively mediated LHPP expression in lung cancer cells. GD55-LHPP could effectively inhibit the proliferation of lung cancer cell lines and rarely affected normal cell growth. Mechanically, the oncolytic adenovirus GD55-LHPP was able to induce stronger apoptosis of lung cancer cells compared with GD55 through the activation of caspase signal pathway. Notably, GD55-LHPP also activated autophagy-related signal pathway. Further, GD55-LHPP efficiently inhibited tumor growth in lung cancer xenograft in mice and prolonged animal survival rate compared with the control GD55 or PBS. In conclusion, the novel construct GD55-LHPP provides a valuable strategy for lung cancer-targeted therapy and develop the role of tumor suppress gene LHPP in lung cancer gene therapy.
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Adenoviridae , Apoptose , Neoplasias Pulmonares , Terapia Viral Oncolítica , Vírus Oncolíticos , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Humanos , Animais , Terapia Viral Oncolítica/métodos , Adenoviridae/genética , Vírus Oncolíticos/genética , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Camundongos Nus , Feminino , AutofagiaRESUMO
Trypsin inhibitors derived from plants have various pharmacological activities and promising clinical applications. In our previous study, a Bowman-Birk-type major trypsin inhibitor from foxtail millet bran (FMB-BBTI) was extracted with antiatherosclerotic activity. Currently, we found that FMB-BBTI possesses a prominent anticolorectal cancer (anti-CRC) activity. Further, a recombinant FMB-BBTI (rFMB-BBTI) was successfully expressed in a soluble manner in host strain Escherichia coli. BL21 (DE3) was induced by isopropyl-ß-d-thiogalactoside (0.1 mM) at 37 °C for 3.5 h by the pET28a vector system. Fortunately, a purity greater than 93% of rFMB-BBTI with anti-CRC activity was purified by nickel-nitrilotriacetic acid affinity chromatography. Subsequently, we found that rFMB-BBTI displays a strikingly anti-CRC effect, characterized by the inhibition of cell proliferation and clone formation ability, cell cycle arrest at the G2/M phase, and induction of cell apoptosis. It is interesting that the rFMB-BBTI treatment had no obvious effect on normal colorectal cells in the same concentration range. Importantly, the anti-CRC activity of rFMB-BBTI was further confirmed in the xenografted nude mice model. Taken together, our study highlights the anti-CRC activity of rFMB-BBTI in vitro and in vivo, uncovering the clinical potential of rFMB-BBTI as a targeted agent for CRC in the future.
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Neoplasias Colorretais , Extratos Vegetais , Proteínas de Plantas , Setaria (Planta) , Inibidores da Tripsina , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Expressão Gênica , Camundongos Endogâmicos BALB C , Camundongos Nus , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Setaria (Planta)/genética , Setaria (Planta)/química , Inibidores da Tripsina/farmacologia , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/químicaRESUMO
The role of bone marrow mesenchymal stem cells (BMSCs) in treating radiation-induced brain injury (RIBI) is not completely understood, and assessment methods to directly characterize neurological function are lacking. In this study, we aimed to evaluate the effects of BMSCs treatment on changes in hippocampal neural function in Sprague-Dawley(SD) rats with RIBI, and to evaluate the therapeutic effect of BMSCs by manganese-enhanced magnetic resonance imaging (MEMRI). First, we assessed cognitive function after RIBI treatment with BMSCs using the Morris water maze. Next, we used MEMRI at two time points to observe the treatment effect and explore the correlation between MEMRI and cognitive function. Finally, we evaluated the expression of specific hippocampal neurofunctional proteins, the ultrastructure of hippocampal nerves, and the histological changes in the hippocampus. After BMSCs treatment of RIBI, cognitive dysfunction improved significantly, the expression of hippocampal neurofunctional proteins was increased, the integrity of the hippocampal neural structure was protected, and nerve cell survival was enhanced. The improvement in neurological function was successfully detected by MEMRI, and MEMRI was highly correlated with cognitive function and histological changes. These results suggest that BMSCs treatment of RIBI is an optional modality, and MEMRI can be used for treatment evaluation.
Assuntos
Lesões Encefálicas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Ratos , Animais , Manganês , Ratos Sprague-Dawley , Imageamento por Ressonância Magnética/métodos , Lesões Encefálicas/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Espectroscopia de Ressonância MagnéticaRESUMO
BACKGROUND: Tianhuang formula (THF) is a Chinese medicine prescription that is patented and clinically approved, and has been shown to improve energy metabolism, but the underlying mechanism remains poorly understood. The purpose of this study is to clarify the potential mechanisms of THF in the treatment of type 2 diabetes mellitus (T2DM). METHODS: A murine model of T2DM was induced by high-fat diet (HFD) feeding combined with low-dose streptozocin (STZ) injections, and the diabetic mice were treated with THF by gavaging for consecutive 10 weeks. Fasting blood glucose (FBG), serum insulin, blood lipid, mitochondrial Ca2+ (mCa2+) levels and mitochondrial membrane potential (MMP), as well as ATP production were analyzed. The target genes and proteins expression of visceral adipose tissue (Vat) was tested by RT-PCR and western blot, respectively. The underlying mechanism of the regulating energy metabolism effect of THF was further explored in the insulin resistance model of 3T3-L1 adipocytes cultured with dexamethasone (DXM). RESULTS: THF restored impaired glucose tolerance and insulin resistance in diabetic mice. Serum levels of lipids were significantly decreased, as well as fasting blood glucose and insulin in THF-treated mice. THF regulated mCa2+ uptake, increased MMP and ATP content in VAT. THF increased the mRNA and protein expression of AMPK, phosphorylated AMPK (p-AMPK), MICU1, sirtuin1 (SIRT1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). THF could increase the mCa2+ level of 3T3-L1 adipocytes and regulate mitochondrial function. The protein expression of AMPK, p-AMPK, mCa2+ uniporter (MCU) and MICU1 decreased upon adding AMPK inhibitor compound C to 3T3-L1 adipocytes and the protein expression of MCU and MICU1 decreased upon adding the MCU inhibitor ruthenium red. CONCLUSIONS: These results demonstrated that THF ameliorated glucose and lipid metabolism disorders in T2DM mice through the improvement of AMPK/MICU1 pathway-dependent mitochondrial function in adipose tissue.
Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Camundongos , Trifosfato de Adenosina/metabolismo , Adipócitos , Proteínas Quinases Ativadas por AMP/metabolismo , Glicemia , Proteínas de Ligação ao Cálcio/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta Hiperlipídica , Insulina/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismoRESUMO
TRPC1 enhances cell proliferation and migration in non-small cell lung cancer (NSCLC); however, its effect on NSCLC chemoresistance and stemness remains to be determined. The aim of the current study was to investigate the effect of TRPC1 on NSCLC chemoresistance and stemness and to determine the underlying mechanism of action. Cisplatin-resistant A549 (A549/CDDP) and H460 (H460/CDDP) cells were first established and were then transfected with negative control small interfering (si)RNA (si-NC) or TRPC1 siRNA (si-TRPC1). Cells were then treated with 740 Y-P, a PI3K/Akt agonist. Subsequently, the sensitivity of A549/CDDP and H460/CDDP cells to CDDP was evaluated. Furthermore, the expression levels of CD133 and CD44, and sphere formation ability were also determined. The results showed that the half-maximal inhibitory concentration (IC50) of CDDP was significantly higher in A549/CDDP cells compared with A549 cells and in H460/CDDP cells compared with H460 cells. TRPC1 silencing decreased the IC50 value of CDDP compared with the si-NC group in A549/CDDP (11.78 vs. 21.58 µM; P<0.01) and H460/CDDP (23.76 vs. 43.11 µM; P<0.05) cells. Additionally, TRPC1 knockdown in both cell lines decreased the number of spheres formed compared with the si-NC group. Furthermore, compared with the si-NC group, A549/CDDP cells transfected with si-TRPC1 exhibited decreased levels of both CD133 (P<0.01) and CD44 (P<0.05). However, only CD133 (P<0.05) was downregulated in TRPC1-depleted H460/CDDP cells compared with the si-NC group. In addition, TRPC1 knockdown repressed PI3K/AKT signaling compared with the si-NC group in both A549/CDDP and H460/CDDP cells (all P<0.05). Finally, cell treatment with 740 Y-P reversed the effect of TRPC1 knockdown on PI3K/AKT signaling, chemoresistance, and cancer stemness in A549/CDDP and H460/CDDP cells (all P<0.05). In conclusion, the results of the current study suggested that targeting TRPC1 could attenuate cancer stemness and chemoresistance via suppression of PI3K/AKT signaling in NSCLC.
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Pancreatic cancer is a lethal condition with a rising incidence and often presents at an advanced stage, contributing to abysmal five-year survival rates. Unspecific symptoms and the current lack of biomarkers and screening tools hamper early diagnosis. New technologies for liquid biopsies and their respective evaluation in pancreatic cancer patients have emerged over recent years. The term liquid biopsy summarizes the sampling and analysis of circulating tumor cells (CTCs), small extracellular vesicles (sEVs), and tumor DNA (ctDNA) from body fluids. The major advantages of liquid biopsies rely on their minimal invasiveness and repeatability, allowing serial sampling for dynamic insights to aid diagnosis, particularly early detection, risk stratification, and precision medicine in pancreatic cancer. However, liquid biopsies have not yet developed into a new pillar for clinicians' routine armamentarium. Here, we summarize recent findings on the use of liquid biopsy in pancreatic cancer patients. We discuss current challenges and future perspectives of this potentially powerful alternative to conventional tissue biopsies.
Assuntos
Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Biópsia Líquida , DNA de Neoplasias , Biópsia , Neoplasias PancreáticasRESUMO
OBJECTIVE: Follicle-stimulating hormone (FSH) level changes may be another reason for increasing the risk of cardiovascular disease. In this study, we aimed to investigate the role of FSH in atherosclerosis and its underlying mechanism. METHODS: ApoE-/- mice were divided into 4 groups, namely, the sham group, bilaterally orchidectomized group, FSH group, and testosterone-only group. Blood lipid and hormone levels were tested, aorta Oil Red O staining; the levels of NF-κB, Akt, eNOS, and FSH receptors in the aorta were measured by Western blotting. Expression of VCAM-1 was detected via Western blotting and immunohistochemical staining. Human umbilical vein endothelial cells (HUVECs) were used to induce endothelial injury model by adding FSH, and the levels of NF-κB, Akt, eNOS, and FSHR were tested in HUVECs. RESULTS: FSH treatment exacerbated atherosclerotic lesions in ApoE-/- mice. Moreover, FSH could promote the expression of VCAM-1 protein in HUVECs, and this effect was possibly mediated by the activation of NF-κB, while NF-κB activation was further enhanced by the activation of the PI3K/Akt/eNOS pathway. FSH failed to activate Akt and NF-κB in the presence of the PI3K inhibitor LY294002 in HUVECs. CONCLUSION: FSH promoted the development of atherosclerosis by increasing VCAM-1 protein expression via activating PI3K/Akt/NF-κB pathway.
Assuntos
Aterosclerose , Neoplasias da Próstata , Masculino , Camundongos , Humanos , Animais , NF-kappa B/metabolismo , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Androgênios/metabolismo , Androgênios/farmacologia , Antagonistas de Androgênios/metabolismo , Antagonistas de Androgênios/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Camundongos Knockout para ApoE , Neoplasias da Próstata/metabolismo , Aterosclerose/metabolismo , Células Endoteliais da Veia Umbilical Humana , Apolipoproteínas E/genéticaRESUMO
BACKGROUND: Screening for epidermal growth factor receptor (EGFR) mutations is the key to select suitable patients with non-small cell lung cancer (NSCLC) for EGFR-TKI therapy in clinical practice. Nevertheless, tumor tissue that needed for mutation analysis is frequently unavailable, especially for patients with recurrence after operation. Therefore, detection of EGFR from circulating tumor DNA (ctDNA) in patients with NSCLC is a sensitive and convenient method to direct patient sequential treatment strategy. METHODS: One hundred and seventy-nine NSCLC patients with both tumor tissue samples and paired plasma samples were recruited. EGFR mutations were detected in 68 tumor tissue samples and 179 plasma samples using Anlongen Locked Nucleic Acid-Amplification Refractory Mutation System (LNA-ARMS) EGFR Mutation Detection Kit. The remaining 111 tumor tissue samples were detected with the use of multiplex PCR-Based NGS sequence. We calculated the sensitivity, specificity, positive prediction value (PPV) and negative prediction value (NPV) of LAN-ARMS PCR. The objective response rate (ORR) of patients received TKIs therapy was calculated. RESULTS: Of the 179 patients, EGFR mutations were detected in 77 of the 179 tumor tissue samples, with a positive rate of 43.01% (77/179). In addition, EGFR mutations were detected in 42 of the 179 plasma samples. The sensitivity and specificity of LAN-ARMS in detecting EGFR mutations were 57.18% and 98.04% respectively compared to tissue results. The PPV was 95.24%, and NPV was 72.99%. Of the 179 pair of samples, EGFR mutations were inconsistent in 39 pairs of tissue and plasma. The overall agreement of EGFR mutation detection was 78.21% (140/179). The ORR was higher in patients with both tissue and plasma EGFR mutations compared with that in patients with only tissue EGFR mutations (73.33% vs. 68.29%), but the difference was not significant. It was suggested that tissue detection combined with plasma detection could improve the mutation rate. CONCLUSION: In plasma samples, Anlongen LAN-ARMS EGFR Mutation Detection Kit had a high sensitivity and specificity for the detection of EGFR mutations. Anlongen LAN-ARMS EGFR Mutation Detection Kit had the advantages of easy-to-operate and high sensitivity in clinical application.
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African swine fever (ASF), an acute, severe, highly contagious disease caused by African swine fever virus (ASFV) infection in domestic pigs and boars, has a mortality rate of up to 100%. Because effective vaccines and treatments for ASF are lacking, effective control of the spread of ASF remains a great challenge for the pig industry. Host epigenetic regulation is essential for the viral gene transcription. Bromodomain and extraterminal (BET) family proteins, including BRD2, BRD3, BRD4, and BRDT, are epigenetic "readers" critical for gene transcription regulation. Among these proteins, BRD4 recognizes acetylated histones via its two bromodomains (BD1 and BD2) and recruits transcription factors, thereby playing a pivotal role in transcriptional regulation and chromatin remodeling during viral infection. However, how BET/BRD4 regulates ASFV replication and gene transcription is unknown. Here, we randomly selected 12 representative BET family inhibitors and compared their effects on ASFV infection in pig primary alveolar macrophages (PAMs). These were found to inhibit viral infection by interfering viral replication. The four most effective inhibitors (ARV-825, ZL0580, I-BET-762, and PLX51107) were selected for further antiviral activity analysis. These BET/BRD4 inhibitors dose dependently decreased the ASFV titer, viral RNA transcription, and protein production in PAMs. Collectively, we report novel function of BET/BRD4 inhibitors in inducing suppression of ASFV infection, providing insights into the role of BET/BRD4 in the epigenetic regulation of ASFV and potential new strategies for ASF prevention and control. IMPORTANCE Due to the continuing spread of the ASFV in the world and the lack of commercial vaccines, the development of improved control strategies, including antiviral drugs, is urgently needed. BRD4 is an important epigenetic factor and has been commonly used for drug development for tumor treatment. Furthermore, the latest research showed that BET/BRD4 inhibition could suppress replication of virus. In this study, we first showed the inhibitory effect of agents targeting BET/BRD4 on ASFV infection with no significant host cytotoxicity. Then, we found four BET/BRD4 inhibitors that can inhibit ASFV replication, RNA transcription, and protein synthesis. Our findings support the hypothesis that BET/BRD4 can be considered as attractive host targets in antiviral drug discovery against ASFV.
Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Febre Suína Africana/genética , Febre Suína Africana/prevenção & controle , Vírus da Febre Suína Africana/genética , Animais , Antivirais/farmacologia , Epigênese Genética , Masculino , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Suínos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Adsorption of deuterium on the neutral and anionic Aln(λ) (n=1-9, 13; λ=0, -1) clusters has been investigated systematically using density functional theory. The comparisons between the Franck-Condon factor simulated spectra and the measured photoelectron spectroscopy (PES) of Cui and co-workers help to search for the ground-state structures. The results showed that D2 molecule tends to be dissociated on aluminum clusters and forms the radial AlD bond with one aluminum atom. By studying the evolution of the binding energies, second difference energies and HOMO-LUMO gaps as a function of cluster size, we found Al2D2, Al6D2 and Al7D2(Ì) clusters have the stronger relative stability and enhanced chemical stability. Also, considering the larger adsorption energies of these three clusters, we surmised that Al2, Al6 and Al7(Ì) may be the better candidates for dissociative adsorption of D2 molecule among the clusters we studied. Furthermore, the natural population analysis (NPA) and difference electron density were performed and discussed to probe into the localization of the charges and reliable charge-transfer information in AlnD2 and AlnD2(Ì) clusters.
Assuntos
Compostos de Alumínio/química , Deutério/química , Adsorção , Simulação por Computador , Modelos Moleculares , Conformação Molecular , Teoria QuânticaRESUMO
In order to explore new magnetic superhalogens, we have systematically investigated the structures, electrophilic properties, stabilities, magnetic properties, and fragmentation channels of neutral and anionic Fe(m)F(n) (m = 1, 2; n = 1-7) clusters using density functional theory. Our results show that a maximum of six F atoms can be bound atomically to one Fe atom, and the Fe-Fe bonding is not preferred in Fe2F(n)(0/-) clusters. The computed electron affinities (EAs) indicate that FeF(n) with n ≥ 3 are superhalogens, while Fe2F(n) can be classified as superhalogens for n ≥ 5. To further understand their superhalogen characteristic, the natural population analysis charge distribution and the HOMOs of anionic clusters were also analyzed. When the extra negative charge and the content of HOMO are mainly located on F atoms, the clusters could be classified as superhalogens with EAs substantially surpass that of Cl. By calculating the binding energies per atom and the HOMO-LUMO gaps, FeF3, FeF4(-), Fe2F4, Fe2F5(-), and Fe2F7(-) clusters were found to have higher stabilities, corresponding to the Fe atoms that are attained at their favorite +2 and +3 oxidation states. Furthermore, we also predicted the most preferred fragmentation channel and product for all the ground state clusters. Even more striking is the fact that both neutral and anionic Fe(m)F(n) (m = 1, 2; n = 1-7) clusters carry large magnetic moments which mainly come from 3d orbital of iron atom.
RESUMO
The molecular structure/property-affinity relationships of dietary polyphenols non-covalently binding to total plasma proteins of type II diabetes (IIDTPP) were investigated by comparing the binding constants obtained from the fluorescence titration method. An additional methoxy group in flavonoids increased their binding affinities for IIDTPP by 1.38 to 15.85 times. The hydroxylation at the 4' position (Ring B) of flavonols and the 5 position (Ring A) of isoflavones weakened the binding affinities; however, hydroxylation at other positions on flavonoids slightly enhanced or little affected the binding affinities for IIDTPP. The glycosylation of flavonoids slightly decreased or little affected the affinities for IIDTPP by less than 1 order of magnitude. The hydrogenation of the C2[double bond, length as m-dash]C3 double bond of flavone, 6-hydroxyflavone, 6-methoxyflavone and myricetin decreased the binding affinities. The galloylation of catechins significantly improved the binding affinities with IIDTPP approximately 10 to 1000 times. The esterification of gallic acid increased its binding affinity. The hydrophobic force played an important role in the binding interaction between polyphenols and IIDTPP.
Assuntos
Proteínas Sanguíneas/metabolismo , Diabetes Mellitus Tipo 2/sangue , Alimentos , Polifenóis/metabolismo , Sítios de Ligação/fisiologia , Proteínas Sanguíneas/química , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Flavanonas/química , Flavanonas/metabolismo , Flavonas/química , Flavonas/metabolismo , Flavonóis/química , Flavonóis/metabolismo , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Ácido Gálico/metabolismo , Glicosilação , Humanos , Ligação de Hidrogênio , Hidrogenação , Interações Hidrofóbicas e Hidrofílicas , Hidroxilação , Isoflavonas/química , Isoflavonas/metabolismo , Estrutura Molecular , Plantas/química , Polifenóis/química , Ligação Proteica/fisiologia , Espectrometria de Fluorescência , Estilbenos/química , Estilbenos/metabolismo , Relação Estrutura-AtividadeRESUMO
Common human plasma proteins (CHPP), also called blood proteins, are proteins found in blood plasma. The molecular structure/property-affinity relationships of dietary polyphenols noncovalently binding to CHPP were investigated by comparing the binding constants obtained from the fluorescence titration method. An additional methoxy group in flavonoids increased their binding affinities for CHPP by 1.05 to 72.27 times. The hydroxylation on the 4' position (ring B) of flavones and flavonols and the 5 position (ring A) of isoflavones weakened the binding affinities; however, the hydroxylation on other positions of flavonoids slightly enhanced or little affected the binding affinities for CHPP. The glycosylation of flavonoids weakened or slightly affected the affinities for CHPP by 1 order of magnitude. The hydrogenation of the C2âC3 double bond of flavone, 6-hydroxyflavone, 6-methoxyflavone and myricetin decreased the binding affinities about 10.02 to 17.82 times. The galloylation of catechins significantly improved the binding affinities with CHPP about 10 to 1000 times. The esterification of gallic acid increased its binding affinity. The binding affinities with CHPP were strongly influenced by the structural differences of dietary polyphenols. Polyphenols with higher affinities for purified HSA also showed stronger affinities with CHPP. The hydrophobic force played an important role in binding interaction between polyphenols and CHPP.