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1.
J Med Chem ; 67(15): 12521-12533, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39047113

RESUMO

Ferroptosis, a distinctive form of programmed cell death, has been implicated in numerous pathological conditions, and its inhibition is considered a promising therapeutic strategy. Currently, there is a scarcity of efficient antagonists for directly regulating intracellular ferrous iron. Ferritinophagy, an essential process for supplying intracellular labile iron, relies on nuclear receptor coactivator 4 (NCOA4), a selective autophagy receptor for the ferritin iron storage complex, thus playing a pivotal role in ferritinophagy. In this study, we reported a novel von Hippel-Lindau-based NCOA4 degrader, V3, as a potent ferroptosis inhibitor with an intracellular ferrous iron inhibition mechanism. V3 significantly reduced NCOA4 levels and downregulated intracellular ferrous iron (Fe2+) levels, thereby effectively suppressing ferroptosis induced by multiple pathways within cells and alleviating liver damage. This research presents a chemical knockdown tool targeting NCOA4 for further exploration into intracellular ferrous iron in ferroptosis, offering a promising therapeutic avenue for ferroptosis-related acute liver injury.


Assuntos
Ferroptose , Ferro , Coativadores de Receptor Nuclear , Animais , Humanos , Masculino , Camundongos , Descoberta de Drogas , Ferroptose/efeitos dos fármacos , Ferro/metabolismo , Camundongos Endogâmicos C57BL , Coativadores de Receptor Nuclear/metabolismo , Coativadores de Receptor Nuclear/antagonistas & inibidores , Peptídeos/química , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo
2.
ACS Chem Biol ; 16(7): 1243-1254, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34232632

RESUMO

The complex reservoir of metabolite-producing bacteria in the gastrointestinal tract contributes tremendously to human health and disease. Bacterial composition, and by extension gut metabolomic composition, is undoubtably influenced by the use of modern antibiotics. Herein, we demonstrate that polymyxin B, a last resort antibiotic, influences the production of the genotoxic metabolite colibactin from adherent-invasive Escherichia coli (AIEC) NC101. Colibactin can promote colorectal cancer through DNA double stranded breaks and interstrand cross-links. While the structure and biosynthesis of colibactin have been elucidated, chemical-induced regulation of its biosynthetic gene cluster and subsequent production of the genotoxin by E. coli are largely unexplored. Using a multiomic approach, we identified that polymyxin B stress enhances the abundance of colibactin biosynthesis proteins (Clb's) in multiple pks+ E. coli strains, including pro-carcinogenic AIEC, NC101; the probiotic strain, Nissle 1917; and the antibiotic testing strain, ATCC 25922. Expression analysis via qPCR revealed that increased transcription of clb genes likely contributes to elevated Clb protein levels in NC101. Enhanced production of Clb's by NC101 under polymyxin stress matched an increased production of the colibactin prodrug motif, a proxy for the mature genotoxic metabolite. Furthermore, E. coli with a heightened tolerance for polymyxin induced greater mammalian DNA damage, assessed by quantification of γH2AX staining in cultured intestinal epithelial cells. This study establishes a key link between the polymyxin B stress response and colibactin production in pks+ E. coli. Ultimately, our findings will inform future studies investigating colibactin regulation and the ability of seemingly innocuous commensal microbes to induce host disease.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Peptídeos/efeitos dos fármacos , Polimixinas/farmacologia , Animais , Evolução Biológica , Linhagem Celular , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Genes Bacterianos/efeitos dos fármacos , Família Multigênica/efeitos dos fármacos , Mutagênicos/metabolismo , Peptídeo Sintases/genética , Peptídeos/metabolismo , Policetídeo Sintases/genética , Policetídeos/metabolismo , Ratos , Regulação para Cima/efeitos dos fármacos
3.
PLoS Pathog ; 17(5): e1009510, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33956916

RESUMO

Protein conformational diseases are characterized by misfolding and toxic aggregation of metastable proteins, often culminating in neurodegeneration. Enteric bacteria influence the pathogenesis of neurodegenerative diseases; however, the complexity of the human microbiome hinders our understanding of how individual microbes influence these diseases. Disruption of host protein homeostasis, or proteostasis, affects the onset and progression of these diseases. To investigate the effect of bacteria on host proteostasis, we used Caenorhabditis elegans expressing tissue-specific polyglutamine reporters that detect changes in the protein folding environment. We found that colonization of the C. elegans gut with enteric bacterial pathogens disrupted proteostasis in the intestine, muscle, neurons, and the gonad, while the presence of bacteria that conditionally synthesize butyrate, a molecule previously shown to be beneficial in neurodegenerative disease models, suppressed aggregation and the associated proteotoxicity. Co-colonization with this butyrogenic strain suppressed bacteria-induced protein aggregation, emphasizing the importance of microbial interaction and its impact on host proteostasis. Further experiments demonstrated that the beneficial effect of butyrate depended on the bacteria that colonized the gut and that this protective effect required SKN-1/Nrf2 and DAF-16/FOXO transcription factors. We also found that bacteria-derived protein aggregates contribute to the observed disruption of host proteostasis. Together, these results reveal the significance of enteric infection and gut dysbiosis on the pathogenesis of protein conformational diseases and demonstrate the potential of using butyrate-producing microbes as a preventative and treatment strategy for neurodegenerative disease.


Assuntos
Butiratos/farmacologia , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Infecções por Enterobacteriaceae/complicações , Microbioma Gastrointestinal , Peptídeos/química , Proteostase , Animais , Caenorhabditis elegans/microbiologia , Proteínas de Caenorhabditis elegans/genética , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Humanos , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Dobramento de Proteína
4.
Eur J Endocrinol ; 185(1): 33-45, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33886495

RESUMO

OBJECTIVE: The insulinotropic effect of exogenous, intravenously infused glucose-dependent insulinotropic polypeptide (GIP) is impaired in patients with type 2 diabetes. We evaluated the effects of endogenous GIP in relation to glucose and bone metabolism in patients with type 2 diabetes using a selective GIP receptor antagonist and hypothesized that the effects of endogenous GIP were preserved. DESIGN: A randomized, double-blinded, placebo-controlled, crossover study. METHODS: Ten patients with overweight/obesity and type 2 diabetes (mean±s.d.; HbA1c 52 ± 11 mmol/mol; BMI 32.5 ± 4.8 kg/m2) were included. We infused a selective GIP receptor antagonist, GIP(3-30)NH2 (1200 pmol/kg/min), or placebo (saline) during two separate, 230-min, standardized, liquid mixed meal tests followed by a meal ad libitum. Subcutaneous adipose tissue biopsies were analyzed. RESULTS: Compared with placebo, GIP(3-30)NH2 reduced postprandial insulin secretion (Δbaseline-subtracted area under the curve (bsAUC)C-peptide% ± s.e.m.; -14 ± 6%, P = 0.021) and peak glucagon (Δ% ± s.e.m.; -11 ± 6%, P = 0.046) but had no effect on plasma glucose (P = 0.692). Suppression of bone resorption (assessed by circulating carboxy-terminal collagen crosslinks (CTX)) was impaired during GIP(3-30)NH2 infusion compared with placebo (ΔbsAUCCTX; ±s.e.m.; -4.9 ± 2 ng/mL × min, P = 0.005) corresponding to a ~50% reduction. Compared with placebo, GIP(3-30)NH2 did not affect plasma lipids, meal consumption ad libitum or adipose tissue triglyceride content. CONCLUSIONS: Using a selective GIP receptor antagonist during a meal, we show that endogenous GIP increases postprandial insulin secretion with little effect on postprandial glycaemia but is important for postprandial bone homeostasis in patients with type 2 diabetes.


Assuntos
Glicemia/metabolismo , Reabsorção Óssea/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Polipeptídeo Inibidor Gástrico/metabolismo , Secreção de Insulina/fisiologia , Obesidade/metabolismo , Triglicerídeos/metabolismo , Adulto , Idoso , Glicemia/efeitos dos fármacos , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Comportamento Alimentar/efeitos dos fármacos , Polipeptídeo Inibidor Gástrico/farmacologia , Humanos , Secreção de Insulina/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/farmacologia , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Período Pós-Prandial , Distribuição Aleatória , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/metabolismo
5.
IEEE/ACM Trans Comput Biol Bioinform ; 18(4): 1299-1304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33687847

RESUMO

The novel coronavirus (COVID-19) infections have adopted the shape of a global pandemic now, demanding an urgent vaccine design. The current work reports contriving an anti-coronavirus peptide scanner tool to discern anti-coronavirus targets in the embodiment of peptides. The proffered CoronaPep tool features the fast fingerprinting of the anti-coronavirus target serving supreme prominence in the current bioinformatics research. The anti-coronavirus target protein sequences reported from the current outbreak are scanned against the anti-coronavirus target data-sets via CORONAPEP which provides precision-based anti-coronavirus peptides. This tool is specifically for the coronavirus data, which can predict peptides from the whole genome, or a gene or protein's list. Besides it is relatively fast, accurate, userfriendly and can generate maximum output from the limited information. The availability of tools like CORONAPEP will immeasurably perquisite researchers in the discipline of oncology and structure-based drug design.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/virologia , SARS-CoV-2/química , SARS-CoV-2/efeitos dos fármacos , Software , Proteínas Virais/química , Proteínas Virais/efeitos dos fármacos , Antivirais/farmacologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Biologia Computacional , Bases de Dados de Proteínas/estatística & dados numéricos , Desenho de Fármacos , Genoma Viral , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Humanos , Pandemias , Peptídeos/química , Peptídeos/efeitos dos fármacos , Peptídeos/genética , SARS-CoV-2/genética , Proteínas Virais/genética
6.
Toxicol Lett ; 332: 146-154, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32683294

RESUMO

Occludin is an important tight junction (TJ) protein in pulmonary epithelial cells. In this study, we identified changes in occludin in arsenic-induced lung injury in vivo and in vitro. Upon intratracheal instillation with arsenic trioxide (As2O3) at a daily dose of 30 µg/kg for 1 week, levels of occludin mRNA and protein expression decreased significantly in mouse lung tissue. Levels of occludin mRNA and protein expression in BEAS-2B cells were reduced upon exposure to As2O3 in a concentration- and time-dependent manner. In addition, exposure to As2O3 significantly increased expression of p-p38, p-ERK1/2, p-ELK1, and MLCK in mouse lung tissue and BEAS-2B cells. Treatment with As2O3 induced oxidative stress in mouse lung tissue and BEAS-2B cells. In BEAS-2B cells, exposure to As2O3 reduced transepithelial resistance, which was partially restored with N-acetyl-cysteine (NAC) treatment. Reduced expression of occludin mRNA and protein induced by As2O3 was entirely restored with NAC and resveratrol. However, SB203580, PD98059, and ML-7 partially blocked As2O3-induced occludin reduction in BEAS-2B cells. These results indicate that As2O3 inhibits occludin expression in vivo and in vitro at least partially via the ROS/ERK/ELK1/MLCK and ROS/p38 MAPK signaling pathways.


Assuntos
Arsenitos/toxicidade , Pulmão/metabolismo , Ocludina/biossíntese , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ocludina/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos
7.
Medicine (Baltimore) ; 99(8): e18912, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080074

RESUMO

BACKGROUND: Knee osteoarthritis (KOA) is the most common form of degenerative arthritis. We used Phellinus linteus (PL), which has been well-known anti-inflammatory function. In this study, we will evaluate if PL extract improves symptoms with KOA. METHODS: This study will be an 8-week single-center randomized controlled double-blind clinical trial. Total of 24 subjects with KOA will be enrolled and they will be divided into 3 groups, PL 1,000 mg, PL 1,500 mg and placebo. Subjects will be followed up every 4 weeks with efficacy and safety at the 2nd and 3rd visits. All subjects should maintain a dosage schedule for this protocol. The primary outcome will be assessed with the Korean version of the Western Ontario and McMasters Universities. And the secondary outcomes will be measured using the visual analog scale, quality of life scale (EQ-5D-3L), ESR, C-reactive protein, and C-telopeptide of type-II collagen. Statistical analysis will be performed on the principle of full analysis set. DISCUSSION: This study has inclusion and exclusion criteria and a well-controlled intervention. This clinical trial is the first step to assess the efficacy and safety of PL in patients with KOA. This study will make an important contribution to the literature and aid follow-up research into the use of PL in KOA.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Articulação do Joelho/efeitos dos fármacos , Osteoartrite do Joelho/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Administração Oral , Adulto , Idoso , Sedimentação Sanguínea/efeitos dos fármacos , Proteína C-Reativa/efeitos dos fármacos , Colágeno Tipo I/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Osteoartrite do Joelho/sangue , Osteoartrite do Joelho/patologia , Peptídeos/efeitos dos fármacos , Phellinus , Placebos/administração & dosagem , Extratos Vegetais/uso terapêutico , Estudos Prospectivos , Qualidade de Vida , República da Coreia/epidemiologia , Resultado do Tratamento
8.
Neuropharmacology ; 162: 107803, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31580838

RESUMO

The most common injury of preterm infants is periventricular leukomalacia (PVL) and to date there is still no safe and effective treatment. In our previous studies, leptin has been found to have neuroprotective effects on the preterm ischemia-hypoxia brain damage model rats in animal behavior. To gain insight into the neuroprotective mechanisms of leptin on preterm brain damage model rats, we constructed a comparative peptidomic profiling of hippocampal tissue between leptin-treated after model and preterm ischemia-hypoxia brain damage model rats using a stable isobaric labeling strategy involving tandem mass tag reagents, followed by nano liquid chromatography tandem mass spectrometry. We identified and quantified 4164 peptides, 238 of which were differential expressed in hippocampal tissue in the two groups. A total of 150 peptides were up regulated and 88 peptides were down regulated. These peptides were imported into the Ingenuity Pathway Analysis (IPA) and identified putative roles in nervous system development, function and diseases. We concluded that the preterm ischemia-hypoxia brain damage model with leptin treatment induced peptides changes in hippocampus, and these peptides, especially for the peptides associated "microtubule-associated protein 1b (MAP1b), Elastin (Eln), Piccolo presynaptic cytomatrix protein (Pclo), Zinc finger homeobox 3(Zfhx3), Alpha-kinase 3(Alpk3) and Myosin XVA(Myo15a) ", could be candidate bio-active peptides and participate in neuroprotection of leptin. These may advance our current understanding of the mechanism of leptin's neuroprotective effect on preterm brain damage and may be involved in the etiology of preterm brain damage. Meanwhile, we found that repression of ILK signaling pathway plays a significant role in neuroprotection of leptin. A better understanding of the role of ILK signaling pathway in neuroprotective mechanisms will help scientists and researchers to develop selective, safe and efficacious drug for therapy against human nervous system disorders.


Assuntos
Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Leptina/farmacologia , Fármacos Neuroprotetores/farmacologia , Peptídeos/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Artéria Carótida Primitiva , Proteínas do Citoesqueleto/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Elastina/efeitos dos fármacos , Elastina/metabolismo , Hipocampo/efeitos dos fármacos , Proteínas de Homeodomínio/efeitos dos fármacos , Proteínas de Homeodomínio/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia , Leucomalácia Periventricular/metabolismo , Leucomalácia Periventricular/fisiopatologia , Ligadura , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Miosinas/efeitos dos fármacos , Miosinas/metabolismo , Neuropeptídeos/efeitos dos fármacos , Neuropeptídeos/metabolismo , Peptídeos/efeitos dos fármacos , Proteínas Serina-Treonina Quinases , Ratos , Transdução de Sinais
9.
Dermatol Ther ; 32(5): e13044, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31364786

RESUMO

Acne vulgaris is a chronic inflammatory disease of the pilosebaceous unit. Dermcidin (DCD) is an antimicrobial peptide released from eccrine sweat glands and sebaceous glands. Studies investigating the role of DCD expression in acne development are scarce. The aim of this study was to determine the relationship between DCD expression and acne vulgaris and the effect of oral isotretinoin treatment on DCD levels. Two groups (one patient group and one control group) were included in the study. The patient group consisted of 30 patients with acne vulgaris who were given oral isotretinoin treatment for 6 months until the cumulative dose was attained. Plasma DCD levels were investigated before and 6 months after treatment. The control group comprised 30 volunteer individuals without acne vulgaris or any inflammatory dermatosis. Of the patients, 24 (80%) had Grade 3, 3 (10%) had Grade 1, and 3 (10%) had Grade 4 acne vulgaris, as determined according to the Pillsbury scoring method. The DCD levels in the control group were significantly higher than those in pretreatment patients (39.53 ± 20.2 vs. 28.60 ± 20.12, p = .004). Additionally, pretreatment DCD levels were significantly increased after 6 months of isotretinoin treatment in the patient group (28.60 ± 20.12 vs. 35.07 ± 24.02, p = .012). The mean pretreatment global acne grading system score of 20.86 ± 4.43 was decreased to 5.17 ± 1.91 in patients after treatment (p < .001). This study indicated that DCD plays an important role in the pathogenesis of acne. It demonstrates anti-inflammatory properties in acne vulgaris. Moreover, it was shown that isotretinoin treatment may improve acne vulgaris by increasing DCD levels.


Assuntos
Acne Vulgar/sangue , Acne Vulgar/tratamento farmacológico , Isotretinoína/uso terapêutico , Peptídeos/sangue , Peptídeos/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Valores de Referência , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
10.
J Clin Endocrinol Metab ; 104(7): 2953-2960, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30848791

RESUMO

CONTEXT: The gut-derived incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) have been suggested to play a role in bone metabolism. Exogenous administration of GIP inhibits bone resorption, but the effect of GLP-1 is less clear. Furthermore, the combined effect of exogenous GIP and GLP-1 on bone metabolism is unknown. OBJECTIVE: To investigate the effect of separate and combined infusions of the incretin hormones GIP and GLP-1 on bone resorption and formation. DESIGN: Randomized, double-blinded, placebo-controlled, crossover study including five study days. PARTICIPANTS: Seventeen overweight/obese men. INTERVENTIONS: On the first study day, a 50-g oral glucose tolerance test (OGTT) was performed. On the next four study days, isoglycemic IV glucose infusions (IIGI), mimicking the glucose excursions from the OGTT, were performed with concomitant infusions of GIP (4 pmol/kg/min), GLP-1 (1 pmol/kg/min), GIP+GLP-1 (4 and 1 pmol/kg/min, respectively), or placebo, respectively. PRIMARY OUTCOMES: Changes in bone resorption assessed by measurements of carboxy-terminal type I collagen crosslinks (CTX) and in bone formation as assessed by procollagen type 1 N-terminal propeptide (P1NP) concentrations. RESULTS: During the OGTT, CTX was significantly lowered by 54 ± 13% from baseline (mean ± SD) compared with 28 ± 12% during IIGI + saline (P < 0.0001). During IIGI+GLP-1 and IIGI+GIP, CTX was lowered by 65 ± 16% and 74 ± 9%, respectively, from baseline, whereas IGII+GIP+GLP-1 lowered CTX by 84 ± 4% from baseline. P1NP levels were unaffected by the interventions. CONCLUSIONS: Our data suggest that GLP-1, like GIP, may be involved in regulation of bone resorption and that GIP and GLP-1 together have partially additive inhibitory effects.


Assuntos
Osso e Ossos/efeitos dos fármacos , Polipeptídeo Inibidor Gástrico/farmacologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Incretinas/farmacologia , Obesidade/metabolismo , Osteogênese/efeitos dos fármacos , Adulto , Reabsorção Óssea , Osso e Ossos/metabolismo , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/metabolismo , Fragmentos de Peptídeos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Pró-Colágeno/efeitos dos fármacos , Pró-Colágeno/metabolismo , Distribuição Aleatória
11.
ACS Chem Biol ; 14(1): 118-130, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30507158

RESUMO

Gating modifier toxins (GMTs) from spider venom can inhibit voltage gated sodium channels (NaVs) involved in pain signal transmission, including the NaV1.7 subtype. GMTs have a conserved amphipathic structure that allow them to interact with membranes and also with charged residues in regions of NaV that are exposed at the cell surface. ProTx-II and GpTx-1 are GMTs able to inhibit NaV1.7 with high potency, but they differ in their ability to bind to membranes and in their selectivity over other NaV subtypes. To explore these differences and gain detailed information on their membrane-binding ability and how this relates to potency and selectivity, we examined previously described NaV1.7 potent/selective GpTx-1 analogues and new ProTx-II analogues designed to reduce membrane binding and improve selectivity for NaV1.7. Our studies reveal that the number and type of hydrophobic residues as well as how they are presented at the surface determine the affinity of ProTx-II and GpTx-1 for membranes and that altering these residues can have dramatic effects on NaV inhibitory activity. We demonstrate that strong peptide-membrane interactions are not essential for inhibiting NaV1.7 and propose that hydrophobic interactions instead play an important role in positioning the GMT at the membrane surface proximal to exposed NaV residues, thereby affecting peptide-channel interactions. Our detailed structure-activity relationship study highlights the challenges of designing GMT-based molecules that simultaneously achieve high potency and selectivity for NaV1.7, as single mutations can induce local changes in GMT structure that can have a major impact on NaV-inhibitory activity.


Assuntos
Peptídeos/efeitos dos fármacos , Venenos de Aranha/farmacologia , Animais , Humanos , Peptídeos/química
12.
Neurosci Lett ; 685: 42-49, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30044955

RESUMO

Proteins containing an expanded polyglutamine tract tend to aggregate, leading to the neuronal damage observed in polyglutamine diseases. We recently reported that free electron laser (FEL) irradiation markedly dissociates naked polyglutamine aggregates as well as the aggregate in the 293 T cells. In the present study, we investigated whether FEL irradiation of neuron-like cells with polyglutamine aggregates would restore the cellular damage and dysfunction. The aggregated polyglutamine peptides induced neurite retraction of differentiated SH-SY5Y cells. Upon FEL irradiation, the polyglutamine aggregates in the SH-SY5Y cells were dissociated, and the shorter length of individual neurite, fewer number of neurites per cell and shorter total length of neurite by polyglutamine were inhibited. Same results were essentially obtained in PC12 cells. Moreover, when FEL irradiation was applied to undifferentiated SH-SY5Y cells, the deficits in neuron-like differentiation seen in expanded polyglutamine peptide-containing cells were also rescued. Thus, FEL irradiation restored both the damage and differentiation caused by polyglutamine in neuron-like cells.


Assuntos
Elétrons/uso terapêutico , Lasers , Neurônios/efeitos dos fármacos , Peptídeos/toxicidade , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Humanos , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Neurônios/metabolismo , Células PC12 , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Ratos
13.
Bioconjug Chem ; 29(7): 2176-2180, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29944344

RESUMO

A new glucose-responsive insulin delivery system is fabricated using biomimetic peptide coacervates derived from the Humboldt squid (Dosidicus Gigas) beak. Both insulin and glucose oxidase are coencapsulated within coacervate microdroplets. The glucose oxidase quickly responds to increasing glucose levels to generate a local acidic environment, thereby rapidly triggering the dissociation of pH-sensitive coacervates to release the insulin cargo. The rate of insulin release is dependent on the glucose level, increases under hyperglycemic conditions, and decreases under normoglycemic conditions. This glucose responsiveness mimics pancreatic ß-cell function by releasing insulin according to glucose levels.


Assuntos
Cápsulas/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Insulina/administração & dosagem , Peptídeos/uso terapêutico , Animais , Bico/química , Cápsulas/química , Decapodiformes , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Glucose/metabolismo , Glucose/farmacologia , Glucose Oxidase , Humanos , Concentração de Íons de Hidrogênio , Peptídeos/efeitos dos fármacos
14.
An Acad Bras Cienc ; 90(1): 185-194, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29641758

RESUMO

The N-salicyloyltryptamine (NST) is an indole derivative compound analogue to the alkaloid N-benzoyltryptamine. In the present study, the antiedematogenic activity of NST was investigated in animal models. Firstly, the acute toxicity for NST was assessed according to the OECD Guideline no. 423. The potential NST-induced antiedematogenic activity was evaluated by carrageenan-induced paw edema in rats, as well as by dextran-, compound 48/80-, histamine-, serotonin-, capsaicine-, and prostaglandin E2-induced paw edema in mice. The effect of NST on compound 48/80-induced ex vivo mast cell degranulation on mice mesenteric bed was investigated. No death or alteration of behavioral parameters was observed after administration of NST (2000 mg/kg, i.p.) during the observation time of 14 days. The NST (100 and 200 mg/kg, i.p.) inhibited the carrageenan-induced edema from the 1st to the 5th hour (**p<0.01; ***p<0.001). The edematogenic activity induced by dextran, compound 48/80, histamine, serotonin, capsaicin, and prostaglandin E2 was inhibited by NST (100 mg/kg, i.p.) throughout the observation period (**p<0.01; ***p<0.001). The pretreatment with NST (50, 100 or 200 mg/kg, i.p) attenuates the compound 48/80-induced mast cell degranulation (**p<0.01; ***p<0.001). Thus, the inhibition of both mast cell degranulation and release of endogenous mediators are probably involved in the NST-induced antiedematogenic effect.


Assuntos
Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Salicilatos/farmacologia , Triptaminas/farmacologia , Animais , Anti-Inflamatórios/toxicidade , Carragenina , Modelos Animais de Doenças , Edema/induzido quimicamente , Feminino , Membro Posterior , Mediadores da Inflamação , Masculino , Camundongos , Peptídeos/efeitos dos fármacos , Ratos Wistar , Salicilatos/toxicidade , Fatores de Tempo , Triptaminas/toxicidade
15.
An. acad. bras. ciênc ; 90(1): 185-194, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886919

RESUMO

ABSTRACT The N-salicyloyltryptamine (NST) is an indole derivative compound analogue to the alkaloid N-benzoyltryptamine. In the present study, the antiedematogenic activity of NST was investigated in animal models. Firstly, the acute toxicity for NST was assessed according to the OECD Guideline no. 423. The potential NST-induced antiedematogenic activity was evaluated by carrageenan-induced paw edema in rats, as well as by dextran-, compound 48/80-, histamine-, serotonin-, capsaicine-, and prostaglandin E2-induced paw edema in mice. The effect of NST on compound 48/80-induced ex vivo mast cell degranulation on mice mesenteric bed was investigated. No death or alteration of behavioral parameters was observed after administration of NST (2000 mg/kg, i.p.) during the observation time of 14 days. The NST (100 and 200 mg/kg, i.p.) inhibited the carrageenan-induced edema from the 1st to the 5th hour (**p<0.01; ***p<0.001). The edematogenic activity induced by dextran, compound 48/80, histamine, serotonin, capsaicin, and prostaglandin E2 was inhibited by NST (100 mg/kg, i.p.) throughout the observation period (**p<0.01; ***p<0.001). The pretreatment with NST (50, 100 or 200 mg/kg, i.p) attenuates the compound 48/80-induced mast cell degranulation (**p<0.01; ***p<0.001). Thus, the inhibition of both mast cell degranulation and release of endogenous mediators are probably involved in the NST-induced antiedematogenic effect.


Assuntos
Animais , Masculino , Feminino , Ratos , Triptaminas/farmacologia , Salicilatos/farmacologia , Edema/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Peptídeos/efeitos dos fármacos , Fatores de Tempo , Carragenina , Triptaminas/toxicidade , Salicilatos/toxicidade , Ratos Wistar , Mediadores da Inflamação , Modelos Animais de Doenças , Edema/induzido quimicamente , Membro Posterior , Anti-Inflamatórios/toxicidade
16.
Biochem Biophys Res Commun ; 496(2): 328-334, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29337057

RESUMO

Autophagy in ß cells has been demonstrated to play a pivotal role in cellular homeostasis and the progression of glucose intolerance. Although autophagic activity is affected by metabolic stress both in vivo and in vitro, it remains unclear as to what extent the autophagic status in each ß cell is different from its neighboring cells. To address this question, GFP-LC3 reporter mice, which can visualize the autophagic status of each ß cell as green-fluorescent puncta, were crossed with obese diabetic db/db mice. Imaging of green-fluorescent puncta in the islets of GFP-LC3 mice revealed that ß cells are a heterogeneous population, as the density of GFP-LC3 puncta in each cell was variable. Furthermore, the variability was greater in GFP-LC3; db/db mice than in non-diabetic GFP-LC3; db/+ mice. Furthermore, when GFP-LC3 mice were treated with a low dose of S961, which antagonizes insulin signaling without inducing overt hyperglycemia, the number of ß cells with a high density of GFP puncta was increased, suggesting that insulin resistance affects autophagic status independently of glucose profiles. These results suggest that pancreatic ß cells under metabolic stress are heterogeneous regarding their autophagic status, which provides insights into the cellular dynamics of each ß cell rather than the whole ß-cell population.


Assuntos
Autofagia/efeitos dos fármacos , Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Peptídeos/efeitos dos fármacos , Receptor de Insulina/genética , Animais , Autofagia/genética , Contagem de Células , Células Cultivadas , Cruzamentos Genéticos , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Peptídeos/farmacologia , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/metabolismo , Transdução de Sinais , Análise de Célula Única
17.
Osteoarthritis Cartilage ; 25(12): 1952-1961, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28964890

RESUMO

OBJECTIVE: To investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of ABT-981, a human dual variable domain immunoglobulin simultaneously targeting interleukin (IL)-1α and IL-1ß, in patients with knee osteoarthritis (OA). METHOD: This was a randomized, double-blind, placebo-controlled, single-center study of multiple subcutaneous (SC) injections of ABT-981 in patients with mild-to-moderate OA of the knee (NCT01668511). Three cohorts received ABT-981 (0.3, 1, or 3 mg/kg) or placebo every other week for a total of four SC injections, and one cohort received ABT-981 (3 mg/kg) or placebo every 4 weeks for a total of three SC injections. Assessment of safety and tolerability were the primary objectives. A panel of serum and urine biomarkers of inflammation and joint degradation were evaluated. RESULTS: A total of 36 patients were randomized (ABT-981, n = 28; placebo, n = 8); 31 (86%) completed the study. Adverse event (AE) rates were comparable between ABT-981 and placebo (54% vs 63%). The most common AE reported with ABT-981 vs placebo was injection site erythema (14% vs 0%). ABT-981 significantly reduced absolute neutrophil count and serum concentrations of IL-1α/IL-1ß, high-sensitivity C-reactive protein, and matrix metalloproteinase (MMP)-derived type 1 collagen. Serum concentrations of MMP-derived type 3 collagen and MMP-degraded C-reactive protein demonstrated decreasing trends with ABT-981. Antidrug antibodies were found in 37% of patients but were not associated with the incidence or severity of AEs. CONCLUSION: ABT-981 was generally well tolerated in patients with knee OA and engaged relevant tissue targets, eliciting an anti-inflammatory response. Consequently, ABT-981 may provide clinical benefit to patients with inflammation-driven OA.


Assuntos
Imunoglobulinas/uso terapêutico , Interleucina-1alfa/antagonistas & inibidores , Interleucina-1beta/antagonistas & inibidores , Osteoartrite do Joelho/tratamento farmacológico , Idoso , Agrecanas/efeitos dos fármacos , Agrecanas/metabolismo , Proteína C-Reativa/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Proteína de Matriz Oligomérica de Cartilagem/efeitos dos fármacos , Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Citrulinação , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo II/efeitos dos fármacos , Colágeno Tipo II/metabolismo , Colágeno Tipo III/efeitos dos fármacos , Colágeno Tipo III/metabolismo , Eritema , Feminino , Humanos , Imunoglobulinas/farmacologia , Reação no Local da Injeção , Injeções Subcutâneas , Interleucina-1beta/efeitos dos fármacos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Osteoartrite do Joelho/metabolismo , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Índice de Gravidade de Doença , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vimentina/efeitos dos fármacos , Vimentina/metabolismo
18.
Am J Physiol Endocrinol Metab ; 313(3): E284-E291, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28420649

RESUMO

Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted from the gastrointestinal tract. It is best known for its glucose-dependent insulinotropic effects. GLP-1 is secreted in its intact (active) form (7-36NH2) but is rapidly degraded by the dipeptidyl peptidase 4 (DPP-4) enzyme, converting >90% to the primary metabolite (9-36NH2) before reaching the targets via the circulation. Although originally thought to be inactive or antagonistic, GLP-1 9-36NH2 may have independent actions, and it is therefore relevant to be able to measure it. Because reliable assays were not available, we developed a sandwich ELISA recognizing both GLP-1 9-36NH2 and nonamidated GLP-1 9-37. The ELISA was validated using analytical assay validation guidelines and by comparing it to a subtraction-based method, hitherto employed for estimation of GLP-1 9-36NH2 Its accuracy was evaluated from measurements of plasma obtained during intravenous infusions (1.5 pmol × kg-1 × min-1) of GLP-1 7-36NH2 in healthy subjects and patients with type 2 diabetes. Plasma levels of the endogenous GLP-1 metabolite increased during a meal challenge in patients with type 2 diabetes, and treatment with a DPP-4 inhibitor fully blocked its formation. Accurate measurements of the GLP-1 metabolite may contribute to understanding its physiology and role of GLP-1 in diabetes.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Fragmentos de Peptídeos/análise , Peptídeos/análise , Área Sob a Curva , Diabetes Mellitus Tipo 2/sangue , Inibidores da Dipeptidil Peptidase IV/farmacologia , Peptídeo 1 Semelhante ao Glucagon/análise , Peptídeo 1 Semelhante ao Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Teste de Tolerância a Glucose , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Peptídeos/sangue , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Reprodutibilidade dos Testes
19.
Artigo em Russo | MEDLINE | ID: mdl-28399095

RESUMO

The article is devoted to the comprehensive diagnosis and treatment of perinatal lesions of the nervous system and their consequences in children. Reflects modern approaches to data classification conditions, taking into account ideas on the etiology and pathogenesis of the disease, the clinical manifestations of the main syndromes (excitation and depression, hypertensive, convulsive, movement disorders) as the neonatal period, and in the formation of long-term effects (motor and mental delay and speech development, hyperkinetic syndrome, cerebral palsy and others). Considerable attention is paid to the modern principles of diagnosis (clinical, psychometric, instrumental) and comprehensive rehabilitation (medical, social and psycho-pedagogical) the effects of perinatal lesions of the nervous system. The results of the review of research on the use of the polypeptide and nootropic neurometabolic stimulator - cortexin - in the complex rehabilitation of perinatal lesions of the nervous system and their consequences in children. It is shown that the use of cortexin in treatment of critical conditions in newborns reduced the duration of intensive care and the length of stay of patients in a intensive care unit, the average period of hospital treatment and the stage of the primary neurological rehabilitation 2.5-3 times, but also reduces the frequency of detection of syndromes movement disorders in 2 times, hypertension-hydrocephalic disorders 3 times, vegetative-visceral dysfunctions 5 times. Application cortexin in the rehabilitation of children of the first years of life with the consequences of perinatal CNS indicates a significant improvement in their motor and cognitive functions, as well as predrechevogo and speech development. Application cortexin significantly improved the forecast recovery of motor, cognitive, and neurological status in general, with full compensation by the end of 1 year of life in 90% of patients, and was accompanied by a decline in disability in extremely premature newborns from 13.6% to 4.6% compared to the standard therapy, as well as reduced length of stay in hospital for 14.7 days of hospital stay. Revealed the cumulative effect of the drug: maintained for 6 to 18 months with repeated courses of therapy, his positive influence. High efficiency of cortexin due to a combination of nootropic, neurotrophic, neuroprotective, anticonvulsant and reparative effects, as well as antioxidant, metabolic and anti-stress action, which determines the need for wide application in complex regenerative treatment of perinatal lesions of the nervous system and their consequences.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/reabilitação , Peptídeos/efeitos dos fármacos , Criança , Humanos , Peptídeos e Proteínas de Sinalização Intercelular
20.
J Diet Suppl ; 14(3): 241-251, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27558170

RESUMO

Soy pulp, called "okara" in Japanese, is known as a by-product of the production of bean curd (tofu), and expected to contain a variety of biologically active substances derived from soybean. However, the biological activities of okara ingredients have not yet been fully understood, and the effectiveness of okara as a functional food seems necessary to be further evaluated. Then the effect of okara extract on angiotensin I-converting enzyme (ACE) activity was examined in vitro, and the extract was shown to cause the inhibition of ACE activity in a manner depending on its concentration. Kinetic analysis indicated that this enzyme inhibition was accompanied by an increase in the Km value without any change in Vmax. Further studies suggested that putative inhibitory substances contained in the extract might be heat stable and dialyzable, and recovered mostly in the peptide fraction obtained by a spin-column separation and a high performance liquid chromatography (HPLC) fractionation. Therefore, the extract was speculated to contain small-size peptides responsible for the inhibitory effect of okara extract on ACE activity, and could be expected to improve the hypertensive conditions by reducing the production of hypertensive peptide.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Glycine max/química , Hipertensão/tratamento farmacológico , Extratos Vegetais/farmacologia , Análise de Variância , Angiotensina II/efeitos dos fármacos , Angiotensina II/metabolismo , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Humanos , Peptídeos/efeitos dos fármacos , Proteínas de Soja/farmacologia
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