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1.
Clin Exp Pharmacol Physiol ; 49(10): 1116-1125, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35748804

RESUMO

Signs of metabolic syndrome and prediabetes preceding type 2 diabetes are modelled in an experiment using a high-fat diet (HFD). The aim of this work was to study the effect of a low molecular weight systemically active nerve growth factor mimetic, compound GK-2 (hexamethylenediamide bis[N-monosuccinyl-L-glutamyl-L-lysine]), on indicators of abdominal obesity, basal blood glucose level, glucose tolerance, cholesterol and triglyceride blood levels, as well as the morphological structure of the liver in male Wistar rats fed a HFD. Rats were divided into three groups: one of them received standard food (control) and two others were fed a HFD containing 45% fat, 35% carbohydrates and 20% protein, with a total caloric value of 516 kcal/100 g, over 12 weeks. Starting from the ninth week, for the next 4 weeks, one of the HFD groups was treated orally with saline whilst the other group was treated orally with GK-2 at a dose of 5 mg/kg. GK-2 was found to reduce the basal glycaemia level and improve glucose tolerance, as well as to reduce the blood level of cholesterol by 30% and that of triglycerides by 28% in comparison with the saline-treated HFD animals. GK-2 reduced the degree of abdominal obesity to the level of the healthy animals and eliminated morphological abnormalities in the liver caused by the HFD. The results of the study determine the feasibility of further GK-2 research as a potential agent for prediabetes treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Animais , Glicemia/metabolismo , Colesterol , Dieta Hiperlipídica/efeitos adversos , Glucose , Metabolismo dos Lipídeos , Masculino , Peso Molecular , Fator de Crescimento Neural/metabolismo , Obesidade/tratamento farmacológico , Obesidade Abdominal , Estado Pré-Diabético/tratamento farmacológico , Ratos , Ratos Wistar , Magreza
2.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36012579

RESUMO

Acute lung injury (ALI) as a model of acute respiratory distress syndrome is characterized by inflammation, complex coagulation, and hematologic abnormalities which result in the formation of fibrin-platelet microthrombi in the pulmonary vessels with the rapid development of progressive respiratory dysfunction. We hypothesize that a nebulized fibrinolytic agent, non-immunogenic staphylokinase (nSta), may be useful for ALI therapy. First, the effect of the nebulized nSta (0.2 mg/kg, 1.0 mg/kg, or 2.0 mg/kg) on the coagulogram parameters was studied in healthy rats. ALI was induced in mice by nebulized administration of lipopolysaccharide (LPS) at a dose of 10 mg/kg. nSta (0.2 mg/kg, 0.4 mg/kg or 0.6 mg/kg) was nebulized 30 min, 24 h, and 48 h after LPS administration. The level of pro-inflammatory cytokines was determined in the blood on the 8th day after LPS and nSta administration. The assessment of lung damage was based on their weighing and microscopic analysis. Fibrin/fibrinogen deposition in the lungs was determined by immunohistochemistry. After nSta nebulization in healthy rats, the fibrinogen blood level as well as activated partial thromboplastin time and prothrombin time did not change. In the nebulized ALI model, the mice showed an increase in lung weight due to their edema and rising fibrin deposition. An imbalance of proinflammatory cytokines was also found. Forty percent of mice with ALI without nSta nebulization had died. Nebulized nSta at a dose of 0.2 mg/kg reduced the severity of ALI: a decrease in interstitial edema and inflammatory infiltration was noted. At a dose of 0.4 mg/kg of nebulized nSta, the animals showed no peribronchial edema and the bronchi had an open clear lumen. At a dose of 0.6 mg/kg of nebulized nSta, the manifestations of ALI were completely eliminated. A significant dose-dependent reduction of the fibrin-positive areas in the lungs of mice with ALI was established. Nebulized nSta had a normalizing effect on the proinflammatory cytokines in blood- interleukin (IL)-1α, IL-17A, IL-6, and granulocyte-macrophage colony-stimulating factor (GM-CSF). These data showed the effectiveness of nebulized nSta and the perspectives of its clinical usage in COVID-19 patients with acute respiratory distress syndrome (ARDS).


Assuntos
Lesão Pulmonar Aguda , COVID-19 , Síndrome do Desconforto Respiratório , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Animais , Modelos Animais de Doenças , Fibrina/farmacologia , Fibrinogênio/uso terapêutico , Lipopolissacarídeos/toxicidade , Pulmão , Metaloendopeptidases , Camundongos , Ratos , Síndrome do Desconforto Respiratório/tratamento farmacológico
3.
Artigo em Inglês | MEDLINE | ID: mdl-32189827

RESUMO

Infrared spectra of surface species have been obtained during atomic layer deposition using tris(isopropylcyclopentadienyl)lanthanum, La(iPrCp)3, and water as precursors at 160 °C and 350 °C. Gas-phase spectra of La(iPrCp)3are obtained for comparison. At low temperature, ligand exchange is seen to occur, and carbonate formation is found. With extended purging, the organic ligands are found to be stable on the surface, and carbonates are not formed. These observations indicate that carbonate formation is occurring during exposure to the precursors. At high temperature, the La precursor is observed to decompose leaving an opaque deposit containing relatively little hydrogen.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35240968

RESUMO

BACKGROUND: Growing pieces of evidence demonstrate a close relationship between type 2 diabetes (T2D) and neurodegenerative disorders such as Alzheimer's disease. The similarity of physiological and pathological processes occurring in pancreatic ß-cells and neurons over the course of these pathologies allows raising the question of the practicability of studying neuroprotective substances for their potential antidiabetic activity. OBJECTIVE: This review analyzes studies of antidiabetic and cytoprotective action on pancreatic ß- cells of the neuroprotective compounds that can attenuate the oxidative stress and enhance the expression of neurotrophins: low-molecular-weight NGF mimetic compound GK-2, selective anxiolytic afobazole, antidepressants lithium chloride, and lithium carbonate on the rat streptozotocin model of T2D. RESULTS: It was found that all the above-listed neuroprotective substances have a pronounced antidiabetic activity. The decrease in the ß-cells number, the average area of the pancreatic islets, as well as the violation of their morphological structure caused by the streptozotocin was significantly weakened by the therapy with the investigated neuroprotective substances. The extent of these morphological changes clearly correlates with the antihyperglycemic effect of these compounds. CONCLUSION: The presented data indicate that the neuroprotective substances attenuating the damaging effect of oxidative stress and neurotrophins deficit cannot only protect neurons but also exert their cytoprotective effect towards pancreatic ß-cells. These data may provide a theoretical basis for the further study of neuroprotective drugs as potential therapeutic options for T2D prevention and treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Fármacos Neuroprotetores , Animais , Hipoglicemiantes , Fatores de Crescimento Neural , Ratos , Estreptozocina
5.
Clin Cancer Res ; 18(5): 1257-67, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22247495

RESUMO

PURPOSE: Human papillomavirus (HPV) is linked with a subset of head and neck squamous cell carcinomas (HNSCC). HPV-positive HNSCCs show a better prognosis than HPV-negative HNSCCs, which may be explained by sensitivity of the HPV-positive HNSCCs to ionizing radiation (IR). Although the molecular mechanism behind sensitivity to IR in HPV-positive HNSCCs is unresolved, DNA damage response (DDR) might be a significant determinant of IR sensitivity. An important player in the DDR, SMG-1 (suppressor with morphogenetic effect on genitalia), is a potential tumor suppressor and may therefore be deregulated in cancer. No studies have yet been conducted linking defects in SMG-1 expression with cancer. We investigated whether deregulation of SMG-1 could be responsible for defects in the DDR in oropharyngeal HNSCC. EXPERIMENTAL DESIGN: Expression and promoter methylation status of SMG-1 were investigated in HNSCCs. To identify a functional link between HPV infection and SMG-1, we transfected the HPV-negative cells with an E6/E7 expression construct. SMG-1 short hairpin RNAs were expressed in HPV-negative cells to estimate survival upon IR. RESULTS: Forced E6/E7 expression in HPV-negative cells resulted in SMG-1 promoter hypermethylation and decreased SMG-1 expression. Due to promoter hypermethylation, HPV-positive HNSCC cells and tumors express SMG-1 at lower levels than HPV-negative SCCs. Depletion of SMG-1 in HPV-negative HNSCC cells resulted in increased radiation sensitivity, whereas SMG-1 overexpression protected HPV-positive tumor cells from irradiation. CONCLUSIONS: Levels of SMG-1 expression negatively correlated with HPV status in cancer cell lines and tumors. Diminished SMG-1 expression may contribute to the enhanced response to therapy exhibited by HPV-positive HNSCCs.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Papillomavirus Humano 16/metabolismo , Fosfatidilinositol 3-Quinases/genética , Regiões Promotoras Genéticas , Adulto , Idoso , Apoptose/genética , Proteínas Mutadas de Ataxia Telangiectasia , Carcinoma de Células Escamosas/virologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Tolerância a Radiação/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
7.
J Am Chem Soc ; 125(16): 4694-5, 2003 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-12696872

RESUMO

The synthesis and characterization of several salts of the B(12)F(12)(2-) anion are reported. The potassium salt was prepared in 72% recrystallized yield by treating K(2)B(12)H(12) with liquid HF at 70 degrees C for 14 h and 20% F(2)/N(2) in liquid HF at 25 degrees C for 72 h. The CPh(3)(+), N(n-Bu)(4)(+), NH(n-C(12)H(25))(3)(+), NH(4)(+), and Li(+) salts were prepared by metathesis reactions. The [NH(n-C(12)H(25))(3)](2)[B(12)F(12)] salt is soluble in aromatic hydrocarbon solvents. The B(12)F(12)(2-) anion is remarkably stable. The salts Li(2)B(12)F(12) and [NH(4)](2)[B(12)F(12)] were stable when heated to 450 and 480 degrees C, respectively. The B(12)F(12)(2-) anion did not react with 98% H(2)SO(4), 70% HNO(3), 3 M KOH, a 10-fold excess of Ce(NH(4))(2)(NO(3))(6) in aqueous solution, or metallic sodium in THF. In addition, B(12)F(12)(2-) did not react with metallic lithium in a mixture of ethylene carbonate and dimethyl carbonate, was not reduced at 0 V versus Li(+/0) in that solvent, and underwent a quasi-reversible oxidation at 4.9 V versus Li(+/0). The structure of [CPh(3)](2)[B(12)F(12)] was determined by single-crystal X-ray diffraction: tetragonal, space group I4(1)/acd, a = 19.102(2), b = 19.102(2), c = 20.535(3) A, V = 7492.2(2) A(3), Z = 8, T = 173(2) K, R(1) = 0.064. The B(12)F(12)(2-) anion weakly interacts with the two symmetry related CPh(3)(+) cations via F.C contacts of 3.087(2) A, which are very close to the 3.17 A sum of van der Waals radii for these two atoms. Taken together, the data suggest that B(12)F(12)(2-) may be useful as a very robust weakly coordinating anion.

8.
Inorg Chem ; 42(15): 4489-91, 2003 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-12870929

RESUMO

The ammonioborane monoanion H(3)NB(12)H(11)(-) was per-B-fluorinated with elemental fluorine in liquid hydrogen fluoride to yield the first member of a new class of weakly coordinating anions, H(3)NB(12)F(11)(-) (isolated as [N(n-Bu)(4)](2)[H(2)NB(12)F(11)] in 41% yield). The pK(a) of the H(3)NB(12)F(11)(-) anion is 9.6. Several salts of the tri-N-alkylated anions Me(3)NB(12)F(11)(-) and Dd(3)NB(12)F(11)(-) (Dd = n-C(12)H(25)) were also prepared. The structure of [CPh(3)][Me(3)NB(12)F(11)] was determined by single-crystal X-ray diffraction: monoclinic, space group P2(1)/c, a = 18.053(3) A, b = 33.139(5) A, c = 9.600(2) A, beta = 91.459(4) degrees, V = 5742(2) A(3), Z = 8, T = 173(2) K, R(1) = 0.045. It revealed that the only direct interactions between the undecafluoroammonioborate monoanions and the trityl cations in the two independent ion pairs were long and weak BF...CPh(3) interactions of 2.992(6) and 2.942(6) A. Salts of the new anions were chemically, electrochemically, and thermally stable. The conductivity of Li(Me(3)NB(12)F(11)) in dimethoxyethane was comparable to that of LiPF(6) but less than half the value of Li(1-Me-CB(11)F(11)).

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