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1.
Life Sci ; 219: 190-198, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30658098

RESUMO

AIMS: To initiate a state of artificial torpor we suggested a pharmacological multi-targeting strategy for simulation of the physiological pattern of natural hibernation including a significant reduction in heart rate, respiratory rate, body temperature and oxygen consumption as well as a decline in brain activity known as torpor. MATERIALS AND METHODS: We have developed a composition which initiates a pharmacologically induced torpor-like state (PITS-composition), made up of eight therapeutic agents, inert gas xenon and lipid emulsion served as a drug vehicle. KEY FINDINGS: After a single intravenous injection to rats, PITS-composition causes a rapid decline in heart rate followed by a steady decrease in body temperature from about 38.5 °C to 31.5 °C, at ambient temperature of 22 °C-23 °C. The hypothermic state may continue on average for 16-17 h with the subsequent spontaneous return of heart rate and body temperature to the initial values. In the open field test at torpor the motility, rearing and grooming were suppressed but 4-8 days later they were restored. SIGNIFICANCE: Suspended animation states, including natural hibernation or pharmacologically induced synthetic torpor are of special attention of medicine, since it may improve survival rate after cardiac arrest, brain hemorrhage and ischemia, and during long-term space traveling. The suggested here multi-targeting strategy made possible to develop the pharmacological composition able, after a single intravenous injection, to initiate long, stable and reversible hypothermia and torpor at room temperature. After the torpor, animals were able to spontaneously restore both physiological parameters, and behavioral reactions.


Assuntos
Hipotermia/induzido quimicamente , Torpor/efeitos dos fármacos , Animais , Temperatura Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Difenidramina/administração & dosagem , Difenidramina/farmacologia , Combinação de Medicamentos , Frequência Cardíaca/efeitos dos fármacos , Injeções Intravenosas , Ivabradina/administração & dosagem , Ivabradina/farmacologia , Sulfato de Magnésio/administração & dosagem , Sulfato de Magnésio/farmacologia , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Fenotiazinas/administração & dosagem , Fenotiazinas/farmacologia , Fosfolipídeos/administração & dosagem , Fosfolipídeos/farmacologia , Propranolol/administração & dosagem , Propranolol/farmacologia , Propiltiouracila/administração & dosagem , Propiltiouracila/farmacologia , Ratos , Ratos Wistar , Reserpina/administração & dosagem , Reserpina/farmacologia , Taxa Respiratória/efeitos dos fármacos , Serotonina/administração & dosagem , Serotonina/farmacologia , Sorbitol/administração & dosagem , Sorbitol/farmacologia , Xenônio/administração & dosagem , Xenônio/farmacologia
2.
Molecules ; 20(3): 4359-68, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25759953

RESUMO

We present here the concept of "in-plant" NMR and show that high-resolution NMR spectroscopy is suitable for the analysis of intact plants and can be used to follow the changes in the intraorganismal molecular composition over long time periods. The NMR-based analysis of the effect of different concentrations of heavy water on the aquatic plant Vesicularia dubyana revealed that due to the presence of specific adaptive mechanisms this plant can sustain the presence of up to 85% of D2O. However, it dies in 100% heavy water.


Assuntos
Briófitas/química , Briófitas/metabolismo , Óxido de Deutério/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Briófitas/crescimento & desenvolvimento , Especificidade de Órgãos
3.
PLoS One ; 6(12): e28824, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22194922

RESUMO

The content of human sweat is studied by high-resolution NMR, and the majority of organic components most often found in sweat of conditionally healthy people are identified. Original and simple tools are designed for sweat sampling from different areas of human body. The minimal surface area needed for sampling is in the range of 50-100 cm(2). On all the surface parts of the human body examined in this work, the main constituents forming a sweat metabolic profile are lactate, glycerol, pyruvate, and serine. The only exception is the sole of the foot (planta pedis), where trace amounts of glycerol are found. An attempt is made to explain the presence of specified metabolites and their possible origin.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Metabolômica , Suor/metabolismo , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Biochim Biophys Acta ; 1814(12): 1930-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21816236

RESUMO

The peculiarities of thermal denaturation and interaction with water of the cycle-3 mutant of green fluorescent protein (GFP) were analyzed by NMR techniques and compared with those of bovine carbonic anhydrase II (BCA-II). Irreversible thermal denaturation was accompanied by massive GFP aggregation with no detectable accumulation of soluble denatured protein. Analysis of the spin diffusion data suggested that the internal part of the GFP ß-can is involved in intensive interactions with water molecules. As a result, at high temperatures, the GFP structure does not unfold but rather breaks, consequently leading to enhanced protein aggregation. This is very different from typical BCA-II behavior.


Assuntos
Precipitação Química , Proteínas de Fluorescência Verde/química , Animais , Bovinos , Difusão , Proteínas de Fluorescência Verde/metabolismo , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Desnaturação Proteica , Dobramento de Proteína , Multimerização Proteica/efeitos dos fármacos , Solventes/farmacologia , Temperatura , Termodinâmica , Água/química , Água/metabolismo
5.
Biochim Biophys Acta ; 1784(5): 834-42, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18359304

RESUMO

Aggregation and subsequent development of protein deposition diseases originate from conformational changes in corresponding amyloidogenic proteins. Many proteins unrelated to amyloidoses also fibrillate at the appropriate conditions. These proteins serve as a model for studying the processes of protein misfolding, oligomerization and fibril formation. The accumulated data support the model where protein fibrillogenesis proceeds via the formation of a relatively unfolded amyloidogenic conformation. The urea-induced unfolding of bovine carbonic anhydrase II, BCA II, is characterized by a combination of high-resolution NMR, circular dichroism spectroscopy and small angle X-ray scattering. It is shown that the formation of associates of protein molecules in complex with solvent (water and urea), APS, takes place in the presence of 4-6 M urea. The subsequent increase in urea concentration to 8 M is accompanied by a disruption of APS and leads to a complete unfolding of a protein molecule. Analysis of BCA II self-association in the presence of 4.2 M urea revealed that APS are relatively large mostly beta-structural blocks with the averaged molecular mass of 190-220 kDa. This work also demonstrates some novel NMR-based methodological approaches that provide useful information on protein self-association.


Assuntos
Anidrase Carbônica II/química , Anidrase Carbônica II/metabolismo , Animais , Bovinos , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Desnaturação Proteica/efeitos dos fármacos , Dobramento de Proteína , Estrutura Quaternária de Proteína , Espalhamento a Baixo Ângulo , Fatores de Tempo , Ureia/farmacologia , Difração de Raios X
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