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1.
Food Chem ; 366: 130422, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34392082

RESUMO

Tea cream, produced by interactions among tea ingredients, is undesirable in tea beverage industry. The interaction between bovine serum albumin (BSA) and theaflavin-3,3'-digallate (TFDG, an important component in tea cream and functional substance of black tea) was investigated by fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, synchronous fluorescence spectroscopy, fourier-transform infrared (FT-IR) spectroscopy, and molecular docking technique. Multi-spectroscopic experiments demonstrated that TFDG interacted with BSA via static quenching, and the microenvironment around BSA became more hydrophobicity. FT-IR showed that the α-helix of BSA was increased when binding with TFDG. Thermodynamic parameters and molecular docking demonstrated that hydrophobic interactions and hydrogen bonds dominated the interaction between TFDG and BSA. The mechanism proposed in this research could further develop some nanoparticles to excellent biochemical properties while reducing the formation of tea cream, and explore the potential of BSA as transport carrier for TFDG.


Assuntos
Soroalbumina Bovina , Biflavonoides , Sítios de Ligação , Catequina/análogos & derivados , Dicroísmo Circular , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
2.
Parasitol Int ; 86: 102458, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34509671

RESUMO

Leishmaniasis chemotherapy is a bottleneck in disease treatment. Although available, chemotherapy is limited, toxic, painful, and does not lead to parasite clearance, with parasite resistance also being reported. Therefore, new therapeutic options are being investigated, such as plant-derived anti-parasitic compounds. Amentoflavone is the most common biflavonoid in the Selaginella genus, and its antileishmanial activity has already been described on Leishmania amazonensis intracellular amastigotes but its direct action on the parasite is controversial. In this work we demonstrate that amentoflavone is active on L. amazonensis promastigotes (IC50 = 28.5 ± 2.0 µM) and amastigotes. Transmission electron microscopy of amentoflavone-treated promastigotes showed myelin-like figures, autophagosomes as well as enlarged mitochondria. Treated parasites also presented multiple lipid droplets and altered basal body organization. Similarly, intracellular amastigotes presented swollen mitochondria, membrane fragments in the lumen of the flagellar pocket as well as autophagic vacuoles. Flow cytometric analysis after TMRE staining showed that amentoflavone strongly decreased mitochondrial membrane potential. In silico analysis shows that amentoflavone physic-chemical, drug-likeness and bioavailability characteristics suggest it might be suitable for oral administration. We concluded that amentoflavone presents a direct effect on L. amazonensis parasites, causing mitochondrial dysfunction and parasite killing. Therefore, all results point for the potential of amentoflavone as a promising candidate for conducting advanced studies for the development of drugs against leishmaniasis.


Assuntos
Biflavonoides/farmacologia , Leishmania mexicana/fisiologia , Mitocôndrias/fisiologia , Selaginellaceae/química , Biflavonoides/química , Leishmania mexicana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Tripanossomicidas
3.
Food Chem ; 370: 131326, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34656020

RESUMO

Theanaphthoquinone (TNQ) is the initial and main oxidation product of theaflavin, a representative black tea pigment. Nevertheless, TNQ is virtually undetected in the high-performance liquid chromatography analysis of black tea leaves using photodiode array detection. To elucidate the degradation mechanism of theaflavin in the black tea production process, this study investigated the reaction of TNQ with epigallocatechin-3-O-gallate (EGCg), which is the most abundant polyphenol in tea leaves. In citrate-phosphate buffer solution at pH 6 and room temperature, TNQ reacted nonenzymatically with EGCg to afford three products, whose structures were determined on the basis of spectroscopic data. The results indicated that the double bond of the ortho-naphthoquinone moiety in TNQ reacted with the autoxidation product of EGCg. This study demonstrates novel reactions occurring in the process of theaflavin degradation, which might be involved in the formation of thearubigins, the major black tea pigments composing oligomeric catechin oxidation products.


Assuntos
Biflavonoides , Catequina , Catequina/análogos & derivados , Chá
4.
J Agric Food Chem ; 69(45): 13596-13607, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34739246

RESUMO

Using a combination of biochemical, transcriptomic, and physiological analyses, we elucidated the mechanisms of physical and chemical withering of tea shoots subjected to UV-C and ethylene treatments. UV-C irradiation (15 kJ m-2) initiated oxidation of catechins into theaflavins, increasing theaflavin-3-monogallate and theaflavin digallate by 5- and 13.2-4.4-fold, respectively, at the end of withering. Concomitantly, a rapid change to brown/red, an increase in electrolyte leakage, and the upregulation of peroxidases (viz. Px2, Px4, and Px6) and polyphenol oxidases (PPO-1) occurred. Exogenous ethylene significantly increased the metabolic rate (40%) and moisture loss (30%) compared to control during simulated withering (12 h at 25 °C) and upregulated transcripts associated with responses to dehydration and abiotic stress, such as those in the ethylene signaling pathway (viz. EIN4-like, EIN3-FBox1, and ERFs). Incorporating ethylene during withering could shorten the tea manufacturing process, while UV-C could enhance the accumulation of flavor-related compounds.


Assuntos
Biflavonoides , Camellia sinensis , Catequina , Antioxidantes , Biflavonoides/análise , Catequina/análise , Catecol Oxidase/genética , Etilenos , Chá
5.
Molecules ; 26(20)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34684702

RESUMO

Procyanidins are contained in various foods, and their effects on starch hydrolysis have been reported. In Japan, black soybeans, which contain a trimeric procyanidin, procyanidin C1 (proC1), are cooked with rice and used to prepare dumplings. In this study, the effects of proC1 on the pancreatin-induced formation of reducing sugars and starch hydrolysis were studied using potato starch and corn starch. ProC1 inhibited both reactions; the inhibition was greater in potato starch than corn starch when added to heated potato starch and corn starch. When heated with proC1, its inhibitory effects decreased, especially in potato starch, suggesting the important role of proC1 itself for the inhibition of potato starch hydrolysis. ProC1 also inhibited the hydrolysis when added to heated, longer amylose (average molecular weight: 31,200), and the inhibition decreased when heated with the amylose. On the other hand, proC1 could not inhibit the hydrolysis when added to heated, shorter amylose (average molecular weight: 4500), but could when heated with the amylose, suggesting the important role of the degradation products of proC1 for the inhibition. We discuss the mechanism of the proC1-dependent inhibition of amylose hydrolysis, taking the molecular weight into account.


Assuntos
Flavonoides/metabolismo , Pancreatina/metabolismo , Amido/química , Amilose/química , Biflavonoides , Catequina , Culinária , Flavonoides/farmacologia , Flavonoides/fisiologia , Hidrólise/efeitos dos fármacos , Japão , Peso Molecular , Oryza/metabolismo , Pancreatina/química , Proantocianidinas , Solanum tuberosum/metabolismo , Amido/metabolismo , Zea mays/metabolismo
6.
J Med Food ; 24(11): 1186-1190, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34698557

RESUMO

Black tea is a popular beverage worldwide. Theaflavins (TFs), which are active functional components of black tea, are potentially valuable for preventing and/or treating the progression of periodontal diseases. Our previous pilot study showed that TF intake decreases the number of Porphyromonas gingivalis (P. gingivalis) bacteria in the saliva. In this study, we aimed to determine whether TF intake improves periodontal disease attributed to oral bacteria in a randomized, placebo-controlled, and double-blind study. A total of 56 healthy subjects without periodontal diseases were enrolled and assigned to the placebo and TF groups (n = 28). TF intake for 6 weeks did not significantly alter the clinical evaluation of subjects. There was no significant adverse effect among the subjects. The number of P. gingivalis and Fusobacterium nucleatum (F. nucleatum) bacteria, which was the primary endpoint in this study, was not impacted by TF intake. The change ratio of Prevotella intermedia was significantly decreased by TF intake (P = .043) when compared with the placebo group. Collectively, our findings suggest that TFs have beneficial effects on oral bacteria for the prevention of periodontal disease. The study protocol was registered in the University Hospital Medical Information Network (UMIN000020049).


Assuntos
Fusobacterium nucleatum , Porphyromonas gingivalis , Aggregatibacter actinomycetemcomitans , Biflavonoides , Catequina , Método Duplo-Cego , Humanos , Japão , Projetos Piloto
7.
Phytomedicine ; 92: 153752, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34601223

RESUMO

BACKGROUND: Cyclophosphamide (CTX), which has been used to treat common female cancers for several years, often causes ovarian damage, early menopause and infertility. However, strategies for the effective prevention and treatment of CTX-induced ovarian damage are still lacking. Epigallocatechin gallate (EGCG) and theaflavins (TFs), key molecules derived from green tea or black tea, have been shown to exert preventive effects on many ageing-related diseases. PURPOSE: We aimed to explore the potential preventive and protective effects of EGCG and TFs on CTX-induced ovarian damage and compare the two compounds. STUDY DESIGN: Six-week-old female mice were administered a low or high dose of EGCG or TFs. The low dose was equivalent to the average daily amount of tea consumed by a drinker. METHODS: We determined the oestrous cycle and serum hormone levels to evaluate ovarian endocrine function, and we performed mating tests for reproductivity. We also assessed the follicle count and AMH level to evaluate ovarian reserve, and we performed Masson's trichrome and Sirius red staining to evaluate ovarian fibrosis. We conducted γ-H2AX and TUNEL analyses to evaluate DNA damage, and we also measured the relevant indicators of oxidative stress and follicular activation, including NRF2, HO-1, SOD2, AKT, mTOR and RPS6. RESULTS: EGCG and TFs treatment independently improved the ovarian endocrine function and reproductivity of mice that were administered CTX. EGCG and TFs also increased the ovarian reserve of these animals. Furthermore, EGCG and TFs alleviated oxidation-induced damage to ovarian DNA in mice by activating the NRF2/HO-1 and SOD2 pathways and reducing the apoptosis of growing follicles. At the same time, EGCG and TFs reduced the overactivation of primordial follicles by inhibiting the AKT/mTOR/RPS6 pathway. CONCLUSION: The present study showed that EGCG and TFs independently improved ovarian function in mice with CTX-induced ovarian damage, thereby providing useful information for designing a potential clinical strategy that will protect against chemotherapy-induced ovarian damage.


Assuntos
Catequina , Atresia Folicular , Animais , Biflavonoides , Catequina/análogos & derivados , Catequina/farmacologia , Ciclofosfamida/toxicidade , Feminino , Camundongos
8.
Molecules ; 26(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641631

RESUMO

Biflavonoids, composed of two monoflavonoid residues, occur naturally in angiosperms, bryophytes, ferns, and gymnosperms. More than 592 biflavonoids have been structurally elucidated, and they can be classified into two groups of C-C and C-linear fragments-C, based on whether the linker between the two residues contains an atom. As the linker can be established on two arbitrary rings from different residues, the C-C type contains various subtypes, as does the C-linear fragment-C type. Biflavonoids have a wide range of pharmacological activities, including anti-inflammatory, antioxidant, antibacterial, antiviral, antidiabetic, antitumor, and cytotoxic properties, and they can be applied in Alzheimer's disease and Parkinson's disease. This review mainly summarizes the distribution and chemistry of biflavonoids; additionally, their bioactivities, pharmacokinetics, and synthesis are discussed.


Assuntos
Biflavonoides/farmacologia , Plantas/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacocinética , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Biflavonoides/química , Biflavonoides/farmacocinética , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Estrutura Molecular
9.
Drug Res (Stuttg) ; 71(8): 462-472, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34517419

RESUMO

BACKGROUND: Replication of SARS-CoV-2 depends on viral RNA-dependent RNA-polymerase (RdRp). Remdesivir, the broad-spectrum RdRp inhibitor acts as nucleoside-analogues (NAs). Remdesivir has initially been repurposed as a promising drug against SARS-CoV-2 infection with some health hazards like liver damage, allergic reaction, low blood-pressure, and breathing-shortness, throat-swelling. In comparison, theaflavin-3'-O-gallate (TFMG), the abundant black tea component has gained importance in controlling viral infection. TFMG is a non-toxic, non-invasive, antioxidant, anticancer and antiviral molecule. RESULTS: Here, we analyzed the inhibitory effect of theaflavin-3'-O-gallate on SARS CoV-2 RdRp in comparison with remdesivir by molecular-docking study. TFMG has been shown more potent in terms of lower Atomic-Contact-Energy (ACE) and higher occupancy of surface area; -393.97 Kcal/mol and 771.90 respectively, favoured with lower desolvation-energy; -9.2: Kcal/mol. TFMG forms more rigid electrostatic and H-bond than remdesivir. TFMG showed strong affinity to RNA primer and template and RNA passage-site of RdRp. CONCLUSIONS: TFMG can block the catalytic residue, NTP entry site, cation binding site, nsp7-nsp12 junction with binding energy of -6. 72 Kcal/mol with Ki value of 11.79, and interface domain with binding energy of -7.72 and -6.16 Kcal/mol with Ki value of 2.21 and 30.71 µM. And most importantly, TFMG shows antioxidant/anti-inflammatory/antiviral effect on human studies.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/farmacologia , Biflavonoides/farmacologia , COVID-19/tratamento farmacológico , Catequina/farmacologia , RNA-Polimerase RNA-Dependente de Coronavírus/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Ácido Gálico/análogos & derivados , Simulação de Acoplamento Molecular , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/química , Monofosfato de Adenosina/farmacologia , Alanina/química , Alanina/farmacologia , Antivirais/química , Biflavonoides/química , COVID-19/virologia , Domínio Catalítico , Catequina/química , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Inibidores Enzimáticos/química , Ácido Gálico/química , Ácido Gálico/farmacologia , Conformação Proteica , SARS-CoV-2/enzimologia , Relação Estrutura-Atividade
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(8): 1158-1164, 2021 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-34549705

RESUMO

OBJECTIVE: To explore whether procyanidin B2 (PCB2) regulates the P13K/Akt/Nrf2 signaling pathway to protect neurons from oxidative stress induced by cypermethrin (CYP). METHODS: Primary cultures of cerebral cortex neurons from C57BL/6 mice were randomly divided into 5 groups: normal control group (cultured in serum-free neurobasal-B27 medium), PCB2 treatment group(treated with 5 µg/mL PCB2 for 24 h), CYP exposure group(treated with 50 µmol/L CYP for 24 h), PCB2 pretreatment group(pretreated with 5 µg/mL PCB2 for 30 min followed by exposure to 50 µmol/L CYP for 24 h), and LY294002 treatment group (pretreated with 20 µmol/L LY294002 for 30 min before treatment with PCB2 for 30 min and then CYP for 24 h).CCK-8 assay was used to analyze the neuronal viability after the treatments.Reactive oxygen species (ROS) production in the cells was detected using the fluorescent probe DCFH-DA and flow cytometry.The changes in nuclear morphology and mitochondrial membrane potential of the cells were examined with Hoechst 33342 and JC-1 staining, respectively.Western blotting was performed to detect the protein expressions of Nrf2, HO-1, p-Akt and Akt in the cells. RESULTS: In CYP exposure group, the cells showed significantly decreased viability and mitochondrial membrane potential with obvious apoptotic morphological changes and abnormal ROS production.By comparison, the cells in PCB2 preconditioning group showed improved cell survival rate, reduced abnormalities in nuclear morphology, increased mitochondrial membrane potential, and lowered intracellular ROS production.CYP exposure caused Nrf2 nuclear translocation and up-regulated Nrf2, HO-1, p-Akt protein expressions in the cells, which were inhibited by PCB2 pretreatment.Inhibition of the P13K/Akt signaling pathway obviously neutralized the protective effect of PCB2 against CYP-induced neuronal injury. CONCLUSIONS: PCB2 regulates the Nrf2/ARE signaling pathway by activating the P13K/Akt signaling pathway to protect mouse cerebral cortical neurons against oxidative injury induced by cypermethrin.


Assuntos
Fator 2 Relacionado a NF-E2 , Proteínas Proto-Oncogênicas c-akt , Animais , Apoptose , Biflavonoides , Catequina , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/metabolismo , Estresse Oxidativo , Proantocianidinas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piretrinas , Espécies Reativas de Oxigênio , Transdução de Sinais
11.
Food Res Int ; 148: 110588, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507733

RESUMO

Monosaccharides of Keemun black tea were quantitatively determined by high performance liquid chromatography coupled with 3-methyl-1-phenyl-2-pyrazolin-5-one (PMP) pre-column derivatization. The methodology of developed analytical method was established with good linearity, recovery, repeatability and precision. The quantitative results showed that D-mannose, D-glucuronic acid, D-glucose, D-galactose and L-arabinose were detected in Keemun black tea samples. D-glucose was the predominant monosaccharide in black tea, and its concentration was continuously increased from fresh tea leaves to fermentation, but after drying its concentration was significantly decreased. Meanwhile, theaflavins' concentrations were obviously decreased after drying. When theaflavins were heated with D-glucose, the loss of theaflavins was increased. Correspondingly, theaflavins also prevented the caramelization of D-glucose and restored the loss of D-glucose during heating. Through the liquid chromatography/electrospray tandem mass spectrometry some theaflavins glucose adducts were identified.


Assuntos
Biflavonoides , Chá , Biflavonoides/análise , Catequina , Glucose , Monossacarídeos
12.
Biomed Pharmacother ; 142: 112011, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34388530

RESUMO

Since the start of the outbreak of coronavirus disease 2019 in Wuhan, China, there have been more than 150 million confirmed cases of the disease reported to the World Health Organization. The beta variant (B.1.351 lineage), the mutation lineages of SARS-CoV-2, had increase transmissibility and resistance to neutralizing antibodies due to multiple mutations in the spike protein. N501Y, K417N and E484K, in the receptor binding domain (RBD) region may induce a conformational change of the spike protein and subsequently increase the infectivity of the beta variant. The L452R mutation in the epsilon variant (the B.1.427/B.1.429 variants) also reduced neutralizing activity of monoclonal antibodies. In this study, we discovered that 300 µg/mL GB-2, from Tian Shang Sheng Mu of Chiayi Puzi Peitian Temple, can inhibit the binding between ACE2 and wild-type (Wuhan type) RBD spike protein. GB-2 can inhibit the binding between ACE2 and RBD with K417N-E484K-N501Y mutation in a dose-dependent manner. GB-2 inhibited the binding between ACE2 and the RBD with a single mutation (K417N or N501Y or L452R) except the E484K mutation. In the compositions of GB-2, glycyrrhiza uralensis Fisch. ex DC., theaflavin and (+)-catechin cannot inhibit the binding between ACE2 and wild-type RBD spike protein. Theaflavin 3-gallate can inhibit the binding between ACE2 and wild-type RBD spike protein. Our results suggest that GB-2 could be a potential candidate for the prophylaxis of some SARS-CoV-2 variants infection in the further clinical study because of its inhibition of binding between ACE2 and RBD with K417N-E484K-N501Y mutations or L452R mutation.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Biflavonoides/farmacologia , COVID-19 , Catequina/farmacologia , Ácido Gálico/análogos & derivados , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Neutralizantes/imunologia , Antioxidantes/farmacologia , Antivirais/farmacologia , COVID-19/imunologia , COVID-19/virologia , Descoberta de Drogas , Ácido Gálico/farmacologia , Células HEK293 , Humanos , Medicina Tradicional do Leste Asiático , Mutação , Ligação Proteica/fisiologia , Domínios e Motivos de Interação entre Proteínas/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
13.
Molecules ; 26(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34443390

RESUMO

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is producing a large number of infections and deaths globally, the development of supportive and auxiliary treatments is attracting increasing attention. Here, we evaluated SARS-CoV-2-inactivation activity of the polyphenol-rich tea leaf extract TY-1 containing concentrated theaflavins and other virucidal catechins. The TY-1 was mixed with SARS-CoV-2 solution, and its virucidal activity was evaluated. To evaluate the inhibition activity of TY-1 in SARS-CoV-2 infection, TY-1 was co-added with SARS-CoV-2 into cell culture media. After 1 h of incubation, the cell culture medium was replaced, and the cells were further incubated in the absence of TY-1. The viral titers were then evaluated. To evaluate the impacts of TY-1 on viral proteins and genome, TY-1-treated SARS-CoV-2 structural proteins and viral RNA were analyzed using western blotting and real-time RT-PCR, respectively. TY-1 showed time- and concentration-dependent virucidal activity. TY-1 inhibited SARS-CoV-2 infection of cells. The results of western blotting and real-time RT-PCR suggested that TY-1 induced structural change in the S2 subunit of the S protein and viral genome destruction, respectively. Our findings provided basic insights in vitro into the possible value of TY-1 as a virucidal agent, which could enhance the current SARS-CoV-2 control measures.


Assuntos
COVID-19/virologia , Polifenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Chá/química , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , COVID-19/tratamento farmacológico , COVID-19/metabolismo , Camellia sinensis/metabolismo , Catequina/química , Catequina/farmacologia , Linhagem Celular , Chlorocebus aethiops , Genoma Viral/efeitos dos fármacos , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polifenóis/isolamento & purificação , SARS-CoV-2/metabolismo , Células Vero , Carga Viral/efeitos dos fármacos
14.
J Agric Food Chem ; 69(33): 9585-9596, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34346218

RESUMO

Inhibiting apical sodium-dependent bile acid transporter (ASBT) has been identified as a potential strategy to reduce plasma cholesterol levels. Thus, in this study, we aimed to identify polyphenols that inhibited ASBT activity and to elucidate their mechanism. ASBT is responsible for most of the taurocholic acid (TC) uptake in Caco-2 cells. Of the 39 polyphenols examined, theaflavin (TF)-3-gallate (TF2A) and theaflavin-3'-gallate (TF2B) have been found to significantly reduce TC uptake in Caco-2 cells to 37.4 ± 2.8 and 33.8 ± 4.0%, respectively, of that in the untreated cells. The results from the TC uptake assay using N-acetylcysteine suggested that the inhibitory effect of TF2A and TF2B was attributed to the oxidization of their benzotropolone rings and their covalent bonding with ASBT's cysteine. TC uptake was reduced in the COS-7 cells expressing recombinant ASBT whose cysteine residues were mutated to alanine. Finally, the substrate concentration-dependent TC uptake assay showed that TFs competitively inhibited TC uptake.


Assuntos
Biflavonoides/farmacologia , Catequina/farmacologia , Transportadores de Ânions Orgânicos Dependentes de Sódio , Simportadores , Ácidos e Sais Biliares , Células CACO-2 , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Simportadores/antagonistas & inibidores , Simportadores/genética , Ácido Taurocólico/metabolismo
15.
Chem Commun (Camb) ; 57(66): 8198-8201, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34304258

RESUMO

At the organelle level, pathogenesis due to abnormal concentrations of cysteine (Cys) is of great significance for the early diagnosis and treatment of related diseases. Generally speaking, organelle localization requires the participation of specific target groups, which increases the difficulty of synthesis. Herein, through simple synthesis, a novel biflavone derivative (BFD) that exhibits excited-state intramolecular proton transfer (ESIPT) was obtained and successfully located in mitochondria without target groups. The probe BFD can distinguish Cys from Hcy and GSH with a rapid response (< 5 s) and showed visual detection for Cys with a large Stokes shift (about 260 nm). Because of its nanomorphology in solution and surface functional groups, the probe BFD can enter the cell smoothly and achieve mitochondrial localization. Owing to its excellent optical performance, the probe BFD was successfully applied to the imaging of endogenous Cys in HeLa cells and zebrafish.


Assuntos
Biflavonoides/química , Cisteína/análise , Corantes Fluorescentes/química , Mitocôndrias/química , Animais , Células HeLa , Humanos , Prótons , Peixe-Zebra
16.
Molecules ; 26(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208050

RESUMO

Potential effects of tea and its constituents on SARS-CoV-2 infection were assessed in vitro. Infectivity of SARS-CoV-2 was decreased to 1/100 to undetectable levels after a treatment with black tea, green tea, roasted green tea, or oolong tea for 1 min. An addition of (-) epigallocatechin gallate (EGCG) significantly inactivated SARS-CoV-2, while the same concentration of theasinensin A (TSA) and galloylated theaflavins including theaflavin 3,3'-di-O-gallate (TFDG) had more remarkable anti-viral activities. EGCG, TSA, and TFDG at 1 mM, 40 µM, and 60 µM, respectively, which are comparable to the concentrations of these compounds in tea beverages, significantly reduced infectivity of the virus, viral RNA replication in cells, and secondary virus production from the cells. EGCG, TSA, and TFDG significantly inhibited interaction between recombinant ACE2 and RBD of S protein. These results suggest potential usefulness of tea in prevention of person-to-person transmission of the novel coronavirus.


Assuntos
Antivirais/farmacologia , Biflavonoides/química , Catequina/química , Ácido Gálico/análogos & derivados , SARS-CoV-2/fisiologia , Chá/química , Replicação Viral/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Antivirais/química , Biflavonoides/farmacologia , COVID-19/patologia , COVID-19/virologia , Catequina/análogos & derivados , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Ácido Gálico/química , Ácido Gálico/farmacologia , Humanos , Mapas de Interação de Proteínas/efeitos dos fármacos , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Chá/metabolismo , Células Vero
17.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201792

RESUMO

Pulse crop seed coats are a sustainable source of antioxidant polyphenols, but are typically treated as low-value products, partly because some polyphenols reduce iron bioavailability in humans. This study correlates antioxidant/iron chelation capabilities of diverse seed coat types from five major pulse crops (common bean, lentil, pea, chickpea and faba bean) with polyphenol composition using mass spectrometry. Untargeted metabolomics was used to identify key differences and a hierarchical analysis revealed that common beans had the most diverse polyphenol profiles among these pulse crops. The highest antioxidant capacities were found in seed coats of black bean and all tannin lentils, followed by maple pea, however, tannin lentils showed much lower iron chelation among these seed coats. Thus, tannin lentils are more desirable sources as natural antioxidants in food applications, whereas black bean and maple pea are more suitable sources for industrial applications. Regardless of pulse crop, proanthocyanidins were primary contributors to antioxidant capacity, and to a lesser extent, anthocyanins and flavan-3-ols, whereas glycosylated flavonols contributed minimally. Higher iron chelation was primarily attributed to proanthocyanidin composition, and also myricetin 3-O-glucoside in black bean. Seed coats having proanthocyanidins that are primarily prodelphinidins show higher iron chelation compared with those containing procyanidins and/or propelargonidins.


Assuntos
Antioxidantes/análise , Cicer/química , Quelantes de Ferro/química , Lens (Planta)/química , Metabolômica/métodos , Polifenóis/análise , Sementes/química , Vicia faba/química , Antioxidantes/química , Biflavonoides/análise , Disponibilidade Biológica , Catequina/análise , Correlação de Dados , Flavonoides/análise , Flavonóis/análise , Concentração Inibidora 50 , Espectrometria de Massas , Fenóis/análise , Proantocianidinas/análise , Taninos/análise
18.
J Agric Food Chem ; 69(29): 8144-8159, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34260232

RESUMO

Drinking tea has been proven to have a positive biological effect in regulating human glucose and lipid metabolism and preventing type 2 diabetes (T2D). Skeletal muscle (SkM) is responsible for 70% of the sugar metabolism in the human body, and its dysfunction is an important factor leading to the development of obesity, T2D, and muscle diseases. As one of the four known theaflavins (TFs) in black tea, the biological role of theaflavin (TF1) in regulating SkM metabolism has not been reported. In this study, mature myotubes induced by C2C12 cells in vitro were used as models. The results showed that TF1 (20 µM) promoted mitochondrial abundance and glucose absorption in myotubes by activating the CaMKK2-AMPK signaling axis via Ca2+ influx. Moreover, it promoted the expression of slow muscle fiber marker genes (Myh7, Myl2, Tnnt1, and Tnnc1) and PGC-1α/SIRT1, as well as enhanced the oxidative phosphorylation capacity of myotubes. In conclusion, this study preliminarily clarified the potential role of TF1 in regulating SkM glucose absorption as well as promoting SkM mitochondrial biosynthesis and slow muscle fiber formation. It has potential research and application values for the prevention/alleviation of SkM-related T2D and Ca2+-related skeletal muscle diseases through diet.


Assuntos
Proteínas Quinases Ativadas por AMP , Diabetes Mellitus Tipo 2 , Biflavonoides , Cálcio , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/genética , Catequina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Glucose , Humanos , Fibras Musculares Esqueléticas , Músculo Esquelético
19.
Int J Mol Sci ; 22(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34281228

RESUMO

Prostate (PC) and breast cancer (BC) are heterogeneous hormonal cancers. Treatment resistance and adverse effects are the main limitations of conventional chemotherapy treatment. The use of sensitizing agents could improve the effectiveness of chemotherapeutic drugs as well as obviate these limitations. This study analyzes the effect of single catechin (CAT), procyanidin B2 (ProB2) treatment as well as the co-adjuvant treatment of each of these compounds with docetaxel (DOCE). We used PC- and BC-derived cell lines (PC3, DU-145, T47D, MCF-7 and MDA-MB-231). The short and long-term pro-apoptotic, anti-proliferative and anti-migratory effects were analyzed. RT-qPCR was used to discover molecular bases of the therapeutic efficacy of these compounds. ProB2 treatment induced a two- to five-fold increase in anti-proliferative and pro-apoptotic effects compared to single DOCE treatment, and also had a more sensitizing effect than DOCE on DU145 cells. Regarding BC cells, ProB2- and CAT-mediated sensitization to DOCE anti-proliferative and pro-apoptotic effects was cell-independent and cell-dependent, respectively. Combined treatment led to high-efficacy effects on MCF-7 cells, which were associated to the up-regulation of CDKN1A, BAX, caspase 9 and E-cadherin mRNA under combined treatment compared to single DOCE treatment. CAT and ProB2 can enhance the efficacy of DOCE therapy on PC and BC cells by the sensitizing mechanism.


Assuntos
Antineoplásicos/uso terapêutico , Biflavonoides/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Catequina/uso terapêutico , Docetaxel/uso terapêutico , Proantocianidinas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Quimioterapia Combinada , Feminino , Humanos , Técnicas In Vitro , Células MCF-7 , Masculino
20.
Chem Biodivers ; 18(8): e2100240, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34081396

RESUMO

Ozoroa obovata (Oliv.) R. & A. Fern. var. obovata found in KwaZulu-Natal in South Africa was investigated for phytochemical constituents, and for antiplasmodial and cytotoxic effects. The plant leaves were collected from the University of KwaZulu-Natal (UKZN) arboretum on the Pietermaritzburg Campus, in March 2019. The inhibitory activity against 3D7 Plasmodium falciparum was determined using the parasite lactate dehydrogenase (pLDH) assay and cytotoxicity against HeLa cells was evaluated using the resazurin assay. The bioactive compounds were isolated by chromatographic purification and their structures were established with spectroscopic and spectrometric techniques. The plant leaf extract displayed significant antiplasmodial activity at 50 µg/mL and was also cytotoxic against HeLa cells. Chromatographic purification of the extract led to the isolation of two biflavonoids, four flavonoid glycosides, a steroid glycoside, and a megastigmene derivative. The compounds displayed antiplasmodial and antiproliferative activities at 50 µg/mL but the activity was substantially reduced at 10 µg/mL. The activities and compounds are being reported in O. obovata for the first time.


Assuntos
Anacardiaceae/química , Antimaláricos/farmacologia , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos , Anacardiaceae/metabolismo , Antimaláricos/química , Antimaláricos/isolamento & purificação , Biflavonoides/química , Biflavonoides/isolamento & purificação , Biflavonoides/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células HeLa , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo
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