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1.
Adv Exp Med Biol ; 1163: 45-64, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31707699

RESUMO

This chapter focuses on protein kinases that transfer the phosphate group of ATP to the hydroxyl group of a substrate protein. Five hundred eighteen human protein kinases are classified into serine/threonine kinases and tyrosine kinases and individually or synergistically transduce physiologic stimuli into cell to promote cell proliferation or apoptosis, etc. Protein kinases are identified as drug targets because dysfunction of kinases leads to severe diseases such as cancers and autoimmune diseases. A large number of the crystal structures of the protein kinase inhibitor complex are available in Protein Data Bank and facilitated the drug discovery targeting protein kinases. The protein kinase inhibitors are classified into categories, Type-I, Type-II, Type-III, Type-IV, and Type-V, and as a separate class, covalent-type inhibitors. In any type, a protein kinase inhibitor bound to the allosteric region is advantageous in terms of selectivity compared to the traditional ATP-competitive one. In the following sections, the successful and promising examples of the partially or fully allosteric protein kinase inhibitors are illustrated in the following pages.


Assuntos
Desenho de Drogas , Inibidores de Proteínas Quinases , Proteínas Quinases , Trifosfato de Adenosina , Descoberta de Drogas , Ativação Enzimática/efeitos dos fármacos , Humanos , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo
2.
Hypertension ; 74(5): 1181-1191, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31564162

RESUMO

Brain renin angiotensin system within the paraventricular nucleus plays a critical role in balancing excitatory and inhibitory inputs to modulate sympathetic output and blood pressure regulation. We previously identified ACE2 and ADAM17 as a compensatory enzyme and a sheddase, respectively, involved in brain renin angiotensin system regulation. Here, we investigated the opposing contribution of ACE2 and ADAM17 to hypothalamic presympathetic activity and ultimately neurogenic hypertension. New mouse models were generated where ACE2 and ADAM17 were selectively knocked down from all neurons (AC-N) or Sim1 neurons (SAT), respectively. Neuronal ACE2 deletion revealed a reduction of inhibitory inputs to AC-N presympathetic neurons relevant to blood pressure regulation. Primary neuron cultures confirmed ACE2 expression on GABAergic neurons synapsing onto excitatory neurons within the hypothalamus but not on glutamatergic neurons. ADAM17 expression was shown to colocalize with angiotensin-II type 1 receptors on Sim1 neurons, and the pressor relevance of this neuronal population was demonstrated by photoactivation. Selective knockdown of ADAM17 was associated with a reduction of FosB gene expression, increased vagal tone, and prevented the acute pressor response to centrally administered angiotensin-II. Chronically, SAT mice exhibited a blunted blood pressure elevation and preserved ACE2 activity during development of salt-sensitive hypertension. Bicuculline injection in those models confirmed the supporting role of ACE2 on GABAergic tone to the paraventricular nucleus. Together, our study demonstrates the contrasting impact of ACE2 and ADAM17 on neuronal excitability of presympathetic neurons within the paraventricular nucleus and the consequences of this mutual regulation in the context of neurogenic hypertension.


Assuntos
Proteína ADAM17/metabolismo , Angiotensina II/farmacologia , Hipertensão/fisiopatologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Peptidil Dipeptidase A/metabolismo , Sistema Renina-Angiotensina/genética , Animais , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiopatologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Hipertensão/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Optogenética/métodos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/patologia , Distribuição Aleatória , Sistema Renina-Angiotensina/efeitos dos fármacos
3.
Cell Physiol Biochem ; 53(3): 518-531, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31502430

RESUMO

BACKGROUND/AIMS: Liver regeneration is induced by S1P and accompanied with an increase in hepatic Na+/K+ ATPase activity, suggesting a potential modulatory role of the sphingolipid on the ATPase activity. The ability of S1P to alter the ATPase activity was confirmed in a previous work which showed a time dependent effect, with an inhibition appearing at 15min and a stimulation at two hours. The aim of this work was to investigate if FTY720-P, an analogue of S1P used in the treatment of multiple sclerosis, exerts a similar effect at 2 hours. METHODS: HepG2 cells were treated with FTY720-P for two hours and the activity of the Na+/K+ ATPase was assayed by measuring the amount of inorganic phosphate liberated in presence and absence of ouabain. The involvement of NF-κB in the pathway was investigated by determining changes in the protein expression of IκB. RESULTS: FTY720-P induced a 2.5-fold increase in the activity of the Na+/K+ ATPase which was maintained in the presence of JTE-013, a specific blocker of S1PR2, but disappeared completely in presence of CAY 10444, a specific S1PR3 antagonist. The involvement of S1PR3 was supported by the stimulation observed with Cym5541, a S1PR3 agonist. FTY720-P increased the expression of COX2, and reduced that of IκB. Its effect was not manifested in presence of indomethacin, a COX inhibitor, or in presence of an NF-κB inhibitor. Exogenous PGE2 induced a significant stimulatory effect. Inhibiting PKC and ERK with respectively calphostin C and PD98059 abolished the effect of FTY720-P on the ATPase and on IκB, but not that of exogenous PGE2 indicating that the two kinases are upstream of NF-κB and PGE2. The PKC activator PMA increased the activity of the Na+/K+ ATPase as well as the expression of phopho-ERK, inferring that PKC is upstream of ERK. CONCLUSION: It was concluded that FTY720-P stimulates the Na+/K+ ATPase via PGE2 by activating sequentially S1PR3, PKC, ERK, NF-κB. The latter enhances COX-2 expression leading to PGE2 release.


Assuntos
Dinoprostona/metabolismo , Organofosfatos/farmacologia , Receptores de Lisoesfingolipídeo/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Esfingosina/análogos & derivados , Western Blotting , Ativação Enzimática/efeitos dos fármacos , Células Hep G2 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esfingosina/farmacologia
4.
Chem Biol Interact ; 313: 108826, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31545954

RESUMO

BACKGROUND: Despite of the most effective surgical removal of malignant tumors, metastasis makes cancer treatment difficult. The studies on natural compounds to inhibit this metastasis have been actively performed until now. However, the effect of tomatidine on metastasis remains unclear. METHOD: The effect of tomatidine on antioxidative activity was measured with DPPH radical assay and reducing power assay. After treatment with tomatidine, the viability of human fibrosarcoma cells (HT1080 cells) was evaluated with MTT assay. The effect of tomatidine on the inhibition of matrix metalloproteinase-2 (MMP-2) and MMP-9, gelatinases related to metastasis, was analyzed using gelatin zymography, western blot and immunofluorescence staining. Cell invasion assay was used to investigate anti-metastasis activity of tomatidine. RESULT: Tomatidine showed no DPPH radical scavenging effect and showed 8% of reduction power at 8 µM. Furthermore, tomatidine below 8 µM showed more than 80% of cell viability in MTT assay. The inhibition of tomatidine on MMP-2 activity and its protein expression levels were observed by gelatin zymography, western blot and immunofluorescence. It was observed that tomatidine inhibited not only p38 and ERK but also cell invasion. CONCLUSION: Above results suggest that tomatidine could use as a potential candidate for cancer prevention and metastasis through the inhibitory effect on gelatinase.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Tomatina/análogos & derivados , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Depuradores de Radicais Livres/farmacologia , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Tomatina/farmacologia , Fator de Transcrição AP-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
5.
Acta Virol ; 63(3): 278-285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507193

RESUMO

Dengue virus (DENV) infection is one of the most widely-spread flavivirus infections with no effective antiviral drugs available. Peptide inhibitors have been considered as one of the best drug candidates due to their high specificity, selectivity in their interactions and minimum side effects. In this study, we employed computational studies using YASARA, HADDOCK server and PyMOL software to generate short and linear peptides based on a reference peptide, CP5-46A, to block DENV NS2B-NS3 protease. The inhibition potencies of the peptides were evaluated using in-house DENV2 serine protease and fluorogenic peptide substrates. In vitro analyses were performed to determine the peptides cytotoxicity and the inhibitory effects against DENV2 replication in WRL-68 cells. Our computational analyses revealed that the docking energy of AYA3, a 16 amino acid (aa) (-81.2 ± 10.6 kcal/mol) and AYA9, a 15 aa peptide (-83.8 ± 6.8 kcal/mol) to DENV NS2B-NS3 protease were much lower than the reference peptide (46 aa; -70.9 ± 7.8 kcal/mol) and the standard protease inhibitor, aprotinin (58 aa; -48.2 ± 10.6 kcal/mol). Both peptides showed significant inhibition against DENV2 NS2B-NS3 protease activity with IC50 values of 24 µM and 23 µM, respectively. AYA3 and AYA9 peptides also demonstrated approximately 68% and 83% of viral plaque reduction without significantly affecting cell viability at 50 µM concentration. In short, we generated short linear peptides with lower cytotoxic effect and substantial antiviral activities against DENV2. Further studies are required to investigate the inhibitory effects of these peptides in vivo. Keywords: peptide inhibitors; dengue virus; NS2B-NS3 protease; plaque reduction.


Assuntos
Antivirais , Vírus da Dengue , Peptídeos , Inibidores de Proteases , Replicação Viral , Antivirais/farmacologia , Biologia Computacional , Vírus da Dengue/enzimologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos/síntese química , Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Replicação Viral/efeitos dos fármacos
6.
Int J Nanomedicine ; 14: 5503-5526, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410001

RESUMO

Background and purpose: Glioma is one of the most aggressive primary brain tumors and is incurable. Surgical resection, radiation, and chemotherapies have been the standard treatments for brain tumors, however, they damage healthy tissue. Therefore, there is a need for safe anticancer drug delivery systems. This is particularly true for natural prodrugs such as thymoquinone (TQ), which has a high therapeutic potential for cancers but has poor water solubility and insufficient targeting capacity. We have tailored novel core-shell nanoformulations for TQ delivery against glioma cells using mesoporous silica nanoparticles (MSNs) as a carrier. Methods: The core-shell nanoformulations were prepared with a core of MSNs loaded with TQ (MSNTQ), and the shell consisted of whey protein and gum Arabic (MSNTQ-WA), or chitosan and stearic acid (MSNTQ-CS). Nanoformulations were characterized, studied for release kinetics and evaluated for anticancer activity on brain cancer cells (SW1088 and A172) and cortical neuronal cells-2 (HCN2) as normal cells. Furthermore, they were evaluated for caspase-3, cytochrome c, cell cycle arrest, and apoptosis to understand the possible anticancer mechanism. Results: TQ release was pH-dependent and different for core and core-shell nanoformulations. A high TQ release from MSNTQ was detected at neutral pH 7.4, while a high TQ release from MSNTQ-WA and MSNTQ-CS was obtained at acidic pH 5.5 and 6.8, respectively; thus, TQ release in acidic tumor environment was enhanced. The release kinetics fitted with the Korsmeyer-Peppas kinetic model corresponding to diffusion-controlled release. Comparative in vitro tests with cancer and normal cells indicated a high anticancer efficiency for MSNTQ-WA compared to free TQ, and low cytotoxicity in the case of normal cells. The core-shell nanoformulations significantly improved caspase-3 activation, cytochrome c triggers, cell cycle arrest at G2/M, and apoptosis induction compared to TQ. Conclusion: Use of MSNs loaded with TQ permit improved cancer targeting and opens the door to translating TQ into clinical application. Particularly good results were obtained for MSNTQ-WA.


Assuntos
Antineoplásicos/uso terapêutico , Benzoquinonas/uso terapêutico , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Glioma/tratamento farmacológico , Nanopartículas/química , Dióxido de Silício/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Materiais Biocompatíveis/química , Encéfalo/patologia , Varredura Diferencial de Calorimetria , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quitosana/química , Citocromos c/metabolismo , Difusão , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Cinética , Nanopartículas/ultraestrutura , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
7.
Pestic Biochem Physiol ; 158: 156-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378352

RESUMO

Culex pipiens is a main vector for Bancroftian filariasis, Rift Valley Fever and diseases caused by other viruses, leaving several peoples with disabilities. In recent years, plant derived compounds have received much attention as potential alternatives to synthetic chemicals due to their low toxicity to mammals and environmental persistence. Twenty-one monoterpenes from different chemical groups (hydrocarbons and oxygenated products) were evaluated against Culex pipiens larvae. In addition, in vivo biochemical studies including effects on acetylcholine esterase (AChE), acid and alkaline phosphatases (ACP and ALP), total adenosine triphosphatase (ATPase) and gamma-aminobutyric acid transaminase (GABA-T) were investigated. Furthermore, in silico studies including pharmacophore elucidation, ADMET analysis and molecular docking of these compounds were performed. Among all tested monoterpenes, hydrocarbons [p-cymene, (R)-(+)-limonene and (+)-α-pinene], acetates (cinnamyl acetate, citronellyl acetate, eugenyl acetate and terpinyl acetate), alcohols [(±)-ß-citronellol and terpineol], aldehydes [citral and (1R)-(-)-myrtenal] and ketone [(R)-(+)-pulegone] exhibited the highest larval toxicity with LC50 = 14.88, 27.97, 26.13, 2.62, 3.81, 2.74, 21.65, 1.64, 21.70, 21.76, 1.68 and 1.90 mg/L after 48 h of exposure, respectively. The compounds proved a significant inhibition of all tested enzymes except total ATPase. The biochemical and molecular docking studies proved that AChE and GABA-T were the main targets for the tested monoterpenes.


Assuntos
Culex/virologia , Inseticidas/farmacologia , Monoterpenos/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Culex/patogenicidade , Filariose Linfática/transmissão , Ativação Enzimática/efeitos dos fármacos , Esterases/metabolismo , Simulação de Acoplamento Molecular , Transaminases/metabolismo
8.
Aquat Toxicol ; 215: 105261, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31419757

RESUMO

Harmful cyanobacteria and their production of microcystins (MCs) exert significant toxicity on reproduction of fish, especially the process of oogenesis. Our previous studies demonstrated that MCs have negative impacts on the quantity and quality of mature oocytes in female zebrafish. However, the underlying mechanisms of MCs disrupting oocyte maturation (OM) have been rarely reported. In the present study, in vitro oocytes (immature) were separated from zebrafish and treated with 1, 10, 100 µg/L MC-LR. The serine/threonine protein phosphatase 2A (PP2A) activity was downregulated significantly in oocytes exposed to 10 and 100 µg/L MC-LR for both 2 and 4 h. The phosphorylation levels of mitogen-activated protein kinase (MAPK) were detected without noticeable change in all oocytes treated with MC-LR for 2 h, whereas the activated levels of MAPK subtypes (ERK, p38 and JNK) increased remarkably in the 100 µg/L MC-LR treatment of 4 h. In the oocytes exposed to 100 µg/L MC-LR for 4 h, germinal vesicle breakdown (GVBD) rates changed abnormally and maturation-promoting factor (MPF) activity increased significantly, in accordance with the upregulation of Cyclin B protein levels. Moreover, the MAPK inhibitors (10 µM) were applied to explore the role of MAPK subtypes during MC-LR influencing OM and results showed that ERK inhibitor U0126 and p38 inhibitor SB203580 mitigated the effects of 100 µg/L MC-LR-induced MAPK hyper-phosphorylation and elevated GVBD in the oocytes. In conclusion, the present study indicates that microcystins disrupt the meiotic maturation by the pathway of MC-PP2A-MAPK-OM due to the phosphorylation disorder in oocytes.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Microcistinas/toxicidade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Peixe-Zebra/fisiologia , Animais , Ciclina B/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Fator Promotor de Maturação/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/enzimologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteína Fosfatase 2/metabolismo , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade
9.
Oncol Rep ; 42(4): 1621-1630, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31322268

RESUMO

One million females are diagnosed worldwide every year with breast cancer, and the mortality rate of these patients remains high. Several treatments, including surgery, are available for breast cancer. ß­Lapachone (ß­Lap), a natural quinone compound, has been developed for cancer treatment due to its strong cytotoxic effect through its action on NAD(P)H:quinone oxidoreductase 1 (NQO1)­dependent activity. However, the mechanism in regards to how ß­Lap induces cytotoxicity in breast cancer cells is still elusive. In the present study, we showed that ß­Lap induced apoptotic cell death via activation of protein kinase A (PKA) in NQO1­overexpressing MDA­MB­231 human breast cancer cells. This PKA­dependent cell death was observed solely in NQO1­overexpressing 231 cells via the high production of reactive oxygen species (ROS). Cell survival of antioxidant [N­acetylcysteine (NAC)]­treated NQO1­overexpressing 231 cells was significantly recovered, and NQO1­negative 231 cells did not respond to ß­Lap. Antiapoptotic proteins such as Bcl2 and Bcl­xL were decreased, while proapoptotic proteins, including cytochrome c, activation of caspase­3, and cleavage of PARP were increased after ß­Lap treatment of NQO1­overexpressing 231 cells. Furthermore, PKA activators, forskolin or dibutyryl­cAMP, an analog of cAMP, aggravated the ß­Lap­induced apoptotic cell death by decreasing antiapoptotic proteins and further activating proapoptotic proteins in NQO1­positive 231 cells. Treatment with a PKA inhibiter, H89, significantly increased cell viability even in NQO1­overexpressing cells treated with ß­Lap. These data showed that ß­Lap activated PKA via ROS accumulation, subsequently leading to apoptotic cell death in NQO1­positive breast cancer cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , NAD(P)H Desidrogenase (Quinona)/biossíntese , Naftoquinonas/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Espécies Reativas de Oxigênio/metabolismo
10.
Cytogenet Genome Res ; 158(1): 17-24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31261155

RESUMO

Osteoarthritis (OA) is a degenerative disease characterized by progressive articular cartilage destruction and joint marginal osteophyte formation with different degrees of synovitis. Docosahexaenoic acid (DHA) is an unsaturated fatty acid with anti-inflammatory, antioxidant, and antiapoptotic functions. In this study, the human chondrosarcoma cell line SW1353 was cultured in vitro, and an OA cell model was constructed with inflammatory factor IL-1ß stimulation. After cells were treated with DHA, cell apoptosis was measured. Western blot assay was used to detect protein expression of apoptosis-related factors (Bax, Bcl-2, and cleaved caspase-3) and mitogen-activated protein kinase (MAPK) signaling pathway family members, including extracellular signal-regulated kinase (ERK), c-JUN N-terminal kinase (JNK), and p38 MAPK. Our results show that IL-1ß promotes the apoptosis of SW1353 cells, increases the expression of Bax and cleaved caspase-3, and activates the MAPK signaling pathway. In contrast, DHA inhibits the expression of IL-1ß, inhibits IL-1ß-induced cell apoptosis, and has a certain inhibitory effect on the activation of the MAPK signaling pathway. When the MAPK signaling pathway is inhibited by its inhibitors, the effects of DHA on SW1353 cells are weakened. Thus, DHA enhances the apoptosis of SW1353 cells through the MAPK signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Condrossarcoma/patologia , Ácidos Docosa-Hexaenoicos/farmacologia , Interleucina-1beta/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Butadienos/farmacologia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Interleucina-1beta/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Nitrilos/farmacologia , Inibidores de Proteínas Quinases/farmacologia
11.
J Enzyme Inhib Med Chem ; 34(1): 1178-1185, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31282230

RESUMO

The activation of the ß-class carbonic anhydrases (CAs, EC 4.2.1.1) from the bacteria Brucella suis and Francisella tularensis with amine and amino acids was investigated. BsuCA 1 was sensitive to activation with amino acids and amines, whereas FtuCA was not. The most effective BsuCA 1 activators were L-adrenaline and D-Tyr (KAs of 0.70-0.95 µM). L-His, L-/D-Phe, L-/D-DOPA, L-Trp, L-Tyr, 4-amino-L-Phe, dopamine, 2-pyridyl-methylamine, D-Glu and L-Gln showed activation constants in the range of 0.70-3.21 µM. FtuCA was sensitive to activation with L-Glu (KA of 9.13 µM). Most of the investigated compounds showed a weak activating effect against FtuCA (KAs of 30.5-78.3 µM). Many of the investigated amino acid and amines are present in high concentrations in many tissues in vertebrates, and their role in the pathogenicity of the two bacteria is poorly understood. Our study may bring insights in processes connected with invasion and pathogenic effects of intracellular bacteria.


Assuntos
Aminas/farmacologia , Aminoácidos/farmacologia , Brucella suis/enzimologia , Anidrases Carbônicas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Francisella tularensis/enzimologia , Aminas/química , Aminoácidos/química , Anidrases Carbônicas/genética , Relação Estrutura-Atividade
12.
Molecules ; 24(11)2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31212689

RESUMO

Verbascoside is found in many medicinal plant families such as Verbenaceae. Important biological activities have been ascribed to verbascoside. Investigated in this study is the potential of verbascoside as an adjuvant during tuberculosis treatment. The present study reports on the in vitro metabolism in human hepatic microsomes and cytosol incubations as well as the presence and quantity of verbascoside within Lippia scaberrima. Additionally, studied are the inhibitory properties on human hepatic CYP enzymes together with antioxidant and cytotoxic properties. The results yielded no metabolites in the hydrolysis or cytochrome P450 (CYP) oxidation incubations. However, five different methylated conjugates of verbascoside could be found in S-adenosylmethionine incubation, three different sulphate conjugates with 3'-phosphoadenosine 5'-phosphosulfate (PAPS) incubation with human liver samples, and very low levels of glucuronide metabolites after incubation with recombinant human uridine 5'-diphospho-glucuronosyltransferase (UGT) 1A7, UGT1A8, and UGT1A10. Additionally, verbascoside showed weak inhibitory potency against CYP1A2 and CYP1B1 with IC50 values of 83 µM and 86 µM, respectively. Potent antioxidant and low cytotoxic potential were observed. Based on these data, verbascoside does not possess any clinically relevant CYP-mediated interaction potential, but it has effective biological activity. Therefore, verbascoside could be considered as a lead compound for further drug development and as an adjuvant during tuberculosis treatment.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Glucosídeos/farmacologia , Fenóis/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Glucosídeos/química , Células Hep G2 , Humanos , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Oxirredução/efeitos dos fármacos , Fenóis/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Picratos/antagonistas & inibidores , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
J Vet Sci ; 20(3): e12, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31161735

RESUMO

The effects of CYP1A enzyme on the pharmacokinetics of p-acetaminophen were studied in Bactrian camel. Twelve Bactrian camels were divided into 2 groups, then given a single dose of p-acetaminophen only or with the enzyme inhibitor lomefloxacin. Blood samples were collected after different intervals, and p-acetaminophen concentration was determined by high-performance liquid chromatography. Pharmacokinetic parameters were analyzed by Phoenix WinNonLin v.7.0. The results show that lomefloxacin can significantly inhibit Bactrian camel CYP1A enzyme, as evidenced by the prolonged elimination half-life, increased maximum plasma concentration and area under the curve values and the shortened time to peak concentration for p-acetaminophenol in the substrate with inhibitor group. The results lay a foundation for revealing the particular characteristics of the CYP1A enzyme in Bactrian camels.


Assuntos
Acetaminofen/farmacocinética , Camelus , Citocromo P-450 CYP1A1/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fluoroquinolonas/farmacologia , Acetaminofen/sangue , Animais , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Meia-Vida
14.
Mar Drugs ; 17(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163615

RESUMO

Sea hares of Aplysia genus are recognized as a source of a diverse range of metabolites. 5α,8α-Endoperoxides belong to a group of oxidized sterols commonly found in marine organisms and display several bioactivities, including antimicrobial, anti-tumor, and immunomodulatory properties. Herein we report the isolation of 5α,8α-epidioxycholest-6-en-3ß-ol (EnP(5,8)) from Aplysia depilans Gmelin, based on bioguided fractionation and nuclear magnetic resonance (NMR) analysis, as well as the first disclosure of its anti-inflammatory properties. EnP(5,8) revealed capacity to decrease cellular nitric oxide (NO) levels in RAW 264.7 macrophages treated with lipopolysaccharide (LPS) by downregulation of the Nos2 (inducible nitric oxide synthase, iNOS) gene. Moreover, EnP(5,8) also inhibited the LPS-induced expression of cyclooxygenase-2 (COX-2), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α) at the mRNA and protein levels. Mild selective inhibition of COX-2 enzyme activity was also evidenced. Our findings provide evidence of EnP(5,8) as a potential lead drug molecule for the development of new anti-inflammatory agents.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Aplysia/química , Ésteres do Colesterol/química , Ésteres do Colesterol/farmacologia , Macrófagos/efeitos dos fármacos , Adjuvantes Imunológicos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Fracionamento Químico , Ésteres do Colesterol/isolamento & purificação , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Células RAW 264.7
15.
Mar Drugs ; 17(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163670

RESUMO

Three new butenolide derivatives, namely aspernolides N-P (1-3), together with six known analogues (4-9), were isolated from the ethyl acetate (EtOAc) extract of the deep sea-derived fungus Aspergillus terreus YPGA10. The structures of compounds 1-3 were determined on the basis of comprehensive analyses of the nuclear magnetic resonance (NMR) and mass spectroscopy (MS) data, and the absolute configurations of 1 and 2 were determined by comparisons of experimental electronic circular dichroism (ECD) with calculated ECD spectra. Compound 1 represents the rare example of Aspergillus-derived butenolide derivatives featured by a monosubstituted benzene ring. Compounds 6-9 exhibited remarkable inhibitory effects against α-glucosidase with IC50 values of 3.87, 1.37, 6.98, and 8.06 µM, respectively, being much more active than the positive control acarbose (190.2 µM).


Assuntos
4-Butirolactona/análogos & derivados , Organismos Aquáticos/química , Aspergillus/química , Inibidores de Glicosídeo Hidrolases/farmacologia , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , 4-Butirolactona/farmacologia , Acetatos/química , Dicroísmo Circular , Ativação Enzimática/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
16.
Mar Drugs ; 17(6)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163697

RESUMO

Largazole, isolated from a marine Cyanobacterium of the genus Symploca, is a potent and selective Class I HDAC (histone deacetylation enzymes) inhibitor. This natural 16-membered macrocyclic depsipeptide features an interesting side chain unit, namely 3-hydroxy-7-mercaptohept-4-enoic acid, which occurs in many other natural sulfur-containing HDAC inhibitors. Notably, one similar fragment, where the amide moiety replaces the trans alkene moiety, appears in Psammaplin A, another marine natural product with potent HDAC inhibitory activities. Inspired by such a structural similarity, we hypothesized the fluoroolefin moiety would mimic both the alkene moiety in Largazole and the amide moiety in Psammaplin A, and thus designed and synthesized two novel fluoro olefin analogs of Largazole. The preliminary biological assays showed that the fluoro analogs possessed comparable Class I HDAC inhibitory effects, indicating that this kind of modification on the side chain of Largazole was tolerable.


Assuntos
Organismos Aquáticos/química , Cianobactérias/química , Depsipeptídeos/síntese química , Depsipeptídeos/farmacologia , Dissulfetos/química , Inibidores de Histona Desacetilases/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Tirosina/análogos & derivados , Alcenos/química , Depsipeptídeos/química , Ativação Enzimática/efeitos dos fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Tiazóis/química , Tirosina/química
17.
Int J Oncol ; 55(1): 59-68, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31180529

RESUMO

The present study investigated the effects of the combined treatment of two peptide nucleic acids (PNAs), directed against microRNAs involved in caspase­3 mRNA regulation (miR­155­5p and miR­221­3p) in the temozolomide (TMZ)­resistant T98G glioma cell line. These PNAs were conjugated with an octaarginine tail in order to obtain an efficient delivery to treated cells. The effects of singularly administered PNAs or a combined treatment with both PNAs were examined on apoptosis, with the aim to determine whether reversion of the drug­resistance phenotype was obtained. Specificity of the PNA­mediated effects was analyzed by reverse transcription­quantitative polymerase­chain reaction, which demonstrated that the effects of R8­PNA­a155 and R8-PNA-a221 anti­miR PNAs were specific. Furthermore, the results obtained confirmed that both PNAs induced apoptosis when used on the temozolomide­resistant T98G glioma cell line. Notably, co­administration of both anti­miR­155 and anti­miR­221 PNAs was associated with an increased proapoptotic activity. In addition, TMZ further increased the induction of apoptosis in T98G cells co­treated with anti­miR­155 and anti­miR­221 PNAs.


Assuntos
Caspase 3/metabolismo , Glioma/tratamento farmacológico , Glioma/genética , MicroRNAs/antagonistas & inibidores , Ácidos Nucleicos Peptídicos/farmacologia , Temozolomida/farmacologia , Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Glioma/enzimologia , Humanos , MicroRNAs/genética , Ácidos Nucleicos Peptídicos/genética
18.
Molecules ; 24(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167480

RESUMO

Lauridia tetragona (L.f) R.H. Archer is routinely used in traditional medicine; however, its hepatoprotective property is yet to be scientifically proven. To this effect, the hepatoprotective activity of the polyphenolic-rich fractions (PPRFs) was investigated against acetaminophen (APAP) injured HepG2 cells. The ability of the PPRF to scavenge free radicals was tested against 2,2-diphenyl-1-picrylhydrazyl (DPPH), and [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonicacid)] (ABTS). The ferric ion reducing power (FRAP) was also evaluated as a cell-free antioxidant assay. The hepatoprotective activity was then investigated by observing the effect of PPRFs against APAP-induced reduction in cell viability of HepG2 cells. The concentrations of alanine aminotransferase (AST), aspartate aminotransferase (ALT) and lactate dehydrogenase (LDH) released into the medium were evaluated while the underlying mechanism was further explored through western blot analysis. Thereafter, the isolated PPRFs were identified using UHPLC-QToF-MS. All six fractions of the PPRFs isolated showed significant antioxidant properties that were evident by the effective scavenging of DPPH, ABTS, and higher FRAP. The results indicated that PPRF pretreatments ameliorated APAP-induced hepatocellular injury by significantly inhibiting the leakage of AST, ALT, and LDH into the medium. The most active fractions for hepatoprotection were PPRF4 and PPRF6 with IC50 of 50.243 ± 8.03 and 154.59 ± 1.9 µg/mL, respectively. PPRFs markedly increased activities of liver superoxide dismutase, total antioxidant capacity, and liver glutathione concentration. Both PPRF4 and PPRF6 significantly increased the expression of Nrf2 and translocation. The LC-MS analysis revealed the presence of a wide variety of polyphenolics such as coumarin, ferulic acid, and caffeine among the dominant constituents. In conclusion, this study demonstrates that the isolated PPRFs have potential hepatoprotective activity that may be due to the increased expression of antioxidative genes dependent on Nrf2.


Assuntos
Acetaminofen/efeitos adversos , Celastraceae/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Substâncias Protetoras/farmacologia , Alanina Transaminase/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia , Aspartato Aminotransferases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Ativação Enzimática/efeitos dos fármacos , Glutationa/metabolismo , Células Hep G2 , Humanos , Concentração Inibidora 50 , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Polifenóis/química , Substâncias Protetoras/química
19.
Artif Cells Nanomed Biotechnol ; 47(1): 2171-2178, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31159596

RESUMO

Nanomedicine is a rapidly emerging field and is reported to be a promising tool for treating various diseases. Green synthesized nanoparticles are documented to possess a potent anticancer effect. Rabdosia rubescens is a Chinese plant which is also one of the components of PC-SPES and used to treat prostate cancer. In the present study, we synthesized the gold nanoparticles from R. rubescens (RR-AuNP) and analyzed its anticancer activity against the lung carcinoma A549 cell lines. Since lung cancer is reported to be with increased morbidity and decreased survival rate. The biosynthesized RR-AuNP were confirmed using UV-Visible spectrophotometer, size and shape of RR-AuNP were assessed by DLS, TEM and EDX. The biomolecules present in RR-AuNP and its topographical structure were detected using FTIR, SAED and AFM analysis. MTT assay was performed to detect the IC50 dose of RR-AuNP and its apoptotic effect was assessed by detecting the caspases activation, ROS generation. The anticancer effect of RR-AuNP was confirmed by DAPI staining, TUNEL assay and its molecular mechanism were confirmed by assessing the apoptotic signalling molecules protein expression. Our results illustrate that RR-AuNP showed a strong absorption peak at 550 nm and the RRAuNP were polydispersed nanospheres with size of 130 nm. RR-AuNP IC50 dose against A549 lung carcinoma cell line was detected to be at 25 µg/ml. The results of DAPI staining, TUNEL and immunoblotting analysis confirms both the 25 µg/ml and 50 µg/ml of RR-AuNP possess potent anticancer and apoptotic effect, suggesting that RR-AuNP that it may be a persuasive molecule to treat lung cancer.


Assuntos
Ouro/química , Ouro/farmacologia , Isodon/química , Neoplasias Pulmonares/patologia , Nanopartículas Metálicas/química , Extratos Vegetais/química , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Técnicas de Química Sintética , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Química Verde , Humanos , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Pestic Biochem Physiol ; 157: 60-68, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153478

RESUMO

A series of novel substituted oxazole isoxazole carboxamides derivatives were designed on the basis of active subunit combination. Forty-four novel compounds were synthesized by an efficient one-pot procedure under microwave irradiation. The bioactivity was evaluated as herbicide safener against the injury of chlorsulfuron. It was found that most of the synthesized compounds displayed remarkable protection against chlorsulfuron via enhanced glutathione content and glutathione S transferase activity. Especially compound I-11 exhibited better bioactivity than the safeners isoxadifen-ethyl and R-28725. Molecular docking simulations suggested that the target compounds could compete with chlorsulfuron in the active site of acetolactate synthase, which could explain the protective effects of safeners. The present work demonstrates that the target compounds containing oxazole isoxazole groups could be considered as potential candidates for developing novel safeners in the future.


Assuntos
Herbicidas/química , Herbicidas/farmacologia , Isoxazóis/química , Oxazóis/química , Sulfonamidas/farmacologia , Triazinas/farmacologia , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Relação Estrutura-Atividade , Zea mays/enzimologia
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