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1.
Int J Mol Sci ; 24(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37569850

RESUMO

Molecular hydrogen (H2) has been recognized as a novel medical gas with antioxidant and anti-inflammatory effects. Non-alcoholic fatty liver disease (NAFLD) is a liver pathology with increased fat accumulation in liver tissue caused by factors other than alcohol consumption. Platelet mitochondrial function is considered to reflect systemic mitochondrial health. We studied the effect of adjuvant therapy with hydrogen-rich water (HRW) on coenzyme Q10 (CoQ10) content and platelet mitochondrial bioenergetics in patients with NAFLD. A total of 30 patients with NAFLD and 15 healthy volunteers were included in this clinical trial. A total of 17 patients (H2 group) drank water three × 330 mL/day with tablets producing HRW (>4 mg/L H2) for 8 weeks, and 13 patients (P group) drank water with placebo tablets producing CO2. The concentration of CoQ10-TOTAL was determined by the HPLC method, the parameter of oxidative stress, thiobarbituric acid reactive substances (TBARS), by the spectrophotometric method, and mitochondrial bioenergetics in platelets isolated from whole blood by high-resolution respirometry. The patients with NAFLD had lower concentrations of CoQ10-TOTAL in the blood, plasma, and platelets vs. the control group. Mitochondrial CI-linked LEAK respiration was higher, and CI-linked oxidative phosphorylation (OXPHOS) and CII-linked electron transfer (ET) capacities were lower vs. the control group. Plasma TBARS concentrations were higher in the H2 group. After 8 weeks of adjuvant therapy with HRW, the concentration of CoQ10 in platelets increased, plasma TBARS decreased, and the efficiency of OXPHOS improved, while in the P group, the changes were non-significant. Long-term supplementation with HRW could be a promising strategy for the acceleration of health recovery in patients with NAFLD. The application of H2 appears to be a new treatment strategy for targeted therapy of mitochondrial disorders. Additional and longer-term studies are needed to confirm and elucidate the exact mechanisms of the mitochondria-targeted effects of H2 therapy in patients with NAFLD.

2.
Viruses ; 15(5)2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37243171

RESUMO

BACKGROUND: Mitochondrial dysfunction and redox cellular imbalance indicate crucial function in COVID-19 pathogenesis. Since 11 March 2020, a global pandemic, health crisis and economic disruption has been caused by SARS-CoV-2 virus. Vaccination is considered one of the most effective strategies for preventing viral infection. We tested the hypothesis that preventive vaccination affects the reduced bioenergetics of platelet mitochondria and the biosynthesis of endogenous coenzyme Q10 (CoQ10) in patients with post-acute COVID-19. MATERIAL AND METHODS: 10 vaccinated patients with post-acute COVID-19 (V + PAC19) and 10 unvaccinated patients with post-acute COVID-19 (PAC19) were included in the study. The control group (C) consisted of 16 healthy volunteers. Platelet mitochondrial bioenergy function was determined with HRR method. CoQ10, γ-tocopherol, α-tocopherol and ß-carotene were determined by HPLC, TBARS (thiobarbituric acid reactive substances) were determined spectrophotometrically. RESULTS: Vaccination protected platelet mitochondrial bioenergy function but not endogenous CoQ10 levels, in patients with post-acute COVID-19. CONCLUSIONS: Vaccination against SARS-CoV-2 virus infection prevented the reduction of platelet mitochondrial respiration and energy production. The mechanism of suppression of CoQ10 levels by SARS-CoV-2 virus is not fully known. Methods for the determination of CoQ10 and HRR can be used for monitoring of mitochondrial bioenergetics and targeted therapy of patients with post-acute COVID-19.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Oxirredução , Mitocôndrias , Vacinação
3.
Bratisl Lek Listy ; 124(2): 89-96, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36598293

RESUMO

BACKGROUND: SARS-CoV-2 infection is associated with inflammation, decrease in antioxidants and oxidative damage. We aimed to investigate whether ubiquinol, reduced form of coenzyme Q10 (CoQ10), with mountain spa rehabilitation (MR) will contribute to recovering of patients with post-COVID-19 syndrome. METHODS: The study included 36 patients on MR lasting 16-18 days. Twenty­two patients were supplemented with ubiquinol 2x100 mg/day (MRQ), 14 underwent MR without supplementation. The control group consisted of 15 healthy volunteers. Concentrations of total CoQ10 (ubiquinone + ubiquinol), α- and γ-tocopherol were determined in platelets (PLT), in blood and plasma, also ß-carotene was determined. Plasma concentration of thiobarbituric acid­reactive substances (TBARS) was used as the oxidative stress marker. Clinical symptoms were evaluated by questionnaire. RESULTS: MRQ group showed a significant increase in CoQ10, namely in PLT by 68 %, in blood by 194 %, and in plasma by 232 %. In MR group, CoQ10 stayed unchanged. In both groups, the initially increased concentrations of tocopherols in PLT returned nearly to the control values. ß-carotene levels decreased in both groups while TBARS decreased slightly in the MRQ group. More clinical symptoms disappeared in the MRQ group. CONCLUSION: Accelerated recovery of patients with post-COVID-19 syndrome was proven after mountain spa rehabilitation and ubiquinol supplementation. Increased systemic and cellular CoQ10 concentration alleviated clinical symptoms and improved antioxidant protection of the patients. We draw attention to the importance of monitoring and ensuring adequate levels of CoQ10 in post-COVID-19 syndrome (Tab. 2, Fig. 1, Ref. 45). Text in PDF www.elis.sk Keywords: COVID-19, mountain spa rehabilitation, ubiquinol, coenzyme Q10, vitamins, TBARS.


Assuntos
COVID-19 , Ubiquinona , Humanos , Ubiquinona/uso terapêutico , Síndrome de COVID-19 Pós-Aguda , Substâncias Reativas com Ácido Tiobarbitúrico , beta Caroteno , SARS-CoV-2 , Antioxidantes/uso terapêutico
4.
Sci Rep ; 13(1): 1700, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717684

RESUMO

We investigated how maternal gestational diabetes (GDM) impacts the metabolic status of offspring. GDM was induced in CD1 mice consuming a fast-food diet (FFD) by repeated low-dose streptozotocin injections before mating. Offspring of normoglycemic standard chow or the FFD consuming dams served as controls. In 4-week-old offspring weaned to standard chow, plasma concentrations of extracellular DNA, inflammatory markers, and parameters of the cardiometabolic status (glycemia, liver lipid content; body, organ, and fat weight) were determined. Two-factor analysis of variance indicated that the male offspring of GDM dams manifest postnatal growth retardation and lower relative kidney weight. Regardless of sex, GDM offspring manifest the lowest IL-1α levels, and other inflammatory markers showed mild and inconsistent alterations. Offspring of dams consuming the FFD displayed higher liver triacylglycerols content. The three groups of offspring showed no significant differences in glycemia and extracellular DNA. Partial least squares-discriminant analysis indicated that male GDM offspring present lower kidney, body, and brown adipose tissue weights; lower IL-1α levels, and higher concentrations of GM-CSF and IL-10 compared with their FFD counterparts. The model failed to select discriminative variables in females. In conclusion, in mice, maternal GDM in the absence of obesity adversely affects the early growth of juvenile male offspring.


Assuntos
Diabetes Gestacional , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Humanos , Feminino , Camundongos , Masculino , Animais , Diabetes Gestacional/metabolismo , Dieta , Obesidade/complicações , Fígado/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo
5.
Environ Sci Pollut Res Int ; 30(6): 14200-14211, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36151435

RESUMO

European Association of Spa Rehabilitation (ESPA) recommends spa rehabilitation for patients with post-COVID-19 syndrome. We tested the hypothesis that a high-altitude environment with clean air and targeted spa rehabilitation (MR - mountain spa rehabilitation) can contribute to the improving platelet mitochondrial bioenergetics, to accelerating patient health and to the reducing socioeconomic problems. Fifteen healthy volunteers and fourteen patients with post-COVID-19 syndrome were included in the study. All parameters were determined before MR (MR1) and 16-18 days after MR (MR2). Platelet mitochondrial respiration and OXPHOS were evaluated using high resolution respirometry method, coenzyme Q10 level was determined by HPLC, and concentration of thiobarbituric acid reactive substances (TBARS) as a parameter of lipid peroxidation was determined spectrophotometrically. This pilot study showed significant improvement of clinical symptoms, lungs function, and regeneration of reduced CI-linked platelet mitochondrial respiration after MR in patients with post-COVID-19 syndrome. High-altitude environment with spa rehabilitation can be recommended for the acceleration of recovery of patients with post-COVID-19 syndrome.


Assuntos
COVID-19 , Humanos , Projetos Piloto , Síndrome de COVID-19 Pós-Aguda , Mitocôndrias , Metabolismo Energético
6.
Front Mol Biosci ; 9: 1016352, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339707

RESUMO

European Association of Spa Rehabilitation recommend spa rehabilitation for patients with post COVID-19 syndrome (post C-19). We studied effects of special mountain spa rehabilitation program and its combination with ubiquinol (reduced form of coenzyme Q10-CoQ10) supplementation on pulmonary function, clinical symptoms, endogenous CoQ10 levels, and platelet mitochondrial bioenergetics of patients with post C-19. 36 patients with post C-19 enrolled for rehabilitation in mountain spa resort and 15 healthy volunteers representing the control group were included in this study. 14 patients with post C-19 (MR group) were on mountain spa rehabilitation lasting 16-18 days, 22 patients (MRQ group) were supplemented with ubiquinol (2 × 100 mg/day) during the rehabilitation and additional 12-14 days at home. Clinical symptoms and functional capacity of the lungs were determined in the patients before and after the spa rehabilitation program. Platelet bioenergetics by high-resolution respirometry, plasma TBARS concentration, and CoQ10 concentration in blood, plasma and platelets were evaluated before and after the spa rehabilitation program, and in 8 patients of MRQ group also after additional 12-14 days of CoQ10 supplementation. Pulmonary function and clinical symptoms improved after the rehabilitation program in both groups, 51.8% of symptoms disappeared in the MR group and 62.8% in the MRQ group. Platelet mitochondrial Complex I (CI)-linked oxidative phosphorylation (OXPHOS) and electron transfer (ET) capacity were markedly reduced in both groups of patients. After the rehabilitation program the improvement of these parameters was significant in the MRQ group and moderate in the MR group. CI-linked OXPHOS and ET capacity increased further after additional 12-14 days of CoQ10 supplementation. CoQ10 concentration in platelets, blood and plasma markedly raised after the spa rehabilitation with ubiquinol supplementation, not in non-supplemented group. In the MRQ group all parameters of platelet mitochondrial respiration correlated with CoQ10 concentration in platelets, and the increase in CI-linked OXPHOS and ET capacity correlated with the increase of CoQ10 concentration in platelets. Our data show a significant role of supplemented ubiquinol in accelerating the recovery of mitochondrial health in patients with post C-19. Mountain spa rehabilitation with coenzyme Q10 supplementation could be recommended to patients with post C-19. This study was registered as a clinical trial: ClinicalTrials.gov ID: NCT05178225.

7.
Exp Gerontol ; 163: 111770, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35314269

RESUMO

Chronic D-galactose administration induces accelerated aging in rodents. The aim of the study was to find by in vivo31P MRS suitable markers of early stages of brain degeneration on this metabolic model in rats. Additionally, we studied the therapeutic effect of antidiabetic drug metformin. The study has been extended by in vitro determination of mitochondrial function in brain, skeletal muscle and liver mitochondria, oxidative stress parameter thiobarbituric acid reactive substances (TBARS), and lipophilic antioxidants levels. In vivo31P MRS revealed lower intracellular pH (pHi) and lower inorganic phosphate to ATP ratio (Pi/ATP), with higher index of oxidative phosphorylation - phosphocreatine (PCr) to Pi ratio - in brain of rats chronically administered with D-galactose. The function of brain mitochondria was not affected. Administration of metformin diminished changes in brain pHi and plasma TBARS. The function of skeletal muscle mitochondria and their coenzyme Q (CoQ) content were considerably reduced after D-galactose administration. Metformin administered simultaneously with D-galactose did not prevent these changes. The results of in vivo31P MRS revealed evidence of early stage of neurodegeneration that may indicate pre-inflammation. Our data show different susceptibility of brain, skeletal muscle, and liver to the chronic exposure to D-galactose and metformin. The D-galactose model presented in the literature as a model for "age-related dementia" had much more devastating effects on skeletal muscle than on the brain.


Assuntos
Galactose , Metformina , Trifosfato de Adenosina/metabolismo , Envelhecimento/metabolismo , Animais , Encéfalo/metabolismo , Metabolismo Energético , Galactose/farmacologia , Fígado/metabolismo , Metformina/farmacologia , Músculo Esquelético/metabolismo , Estresse Oxidativo , Ratos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
8.
PLoS One ; 16(9): e0256135, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582480

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic inflammatory autoimunne disorder affecting both small and large synovial joints, leading to their destruction. Platelet biomarkers are involved in inflammation in RA patients. Increased circulating platelet counts in RA patients may contribute to platelet hyperactivity and thrombosis. In this pilot study we evaluated platelet mitochondrial bioenergy function, CoQ10 levels and oxidative stress in RA patients. METHODS: Twenty-one RA patients and 19 healthy volunteers participated in the study. High resolution respirometry (HRR) was used for analysis of platelet mitochondrial bioenergetics. CoQ10 was determined by HPLC method; TBARS were detected spectrophotometrically. RESULTS: Slight dysfunction in platelet mitochondrial respiration and reduced platelet CoQ10 levels were observed in RA patients compared with normal controls. CONCLUSIONS: The observed decrease in platelet CoQ10 levels may lead to platelet mitochondrial dysfunction in RA diseases. Determination of platelet mitochondrial function and platelet CoQ10 levels could be used as new diagnostic strategies for mitochondrial bioenergetics in rheumatoid diseases.


Assuntos
Artrite Reumatoide/diagnóstico , Biomarcadores/análise , Plaquetas/patologia , Respiração Celular , Mitocôndrias/patologia , Estresse Oxidativo , Ubiquinona/análogos & derivados , Adulto , Idoso , Artrite Reumatoide/metabolismo , Plaquetas/metabolismo , Estudos de Casos e Controles , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Projetos Piloto , Ubiquinona/metabolismo
9.
Int J Mol Sci ; 23(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35008814

RESUMO

Mitochondrial bioenergetics reprogramming is an essential response of cells to stress. Platelets, an accessible source of mitochondria, have a crucial role in cancer development; however, the platelet mitochondrial function has not been studied in urothelial carcinoma (UC) patients. A total of 15 patients with UC and 15 healthy controls were included in the study. Parameters of platelet mitochondrial respiration were evaluated using the high-resolution respirometry method, and the selected antioxidant levels were determined by HPLC. In addition, oxidative stress was evaluated by the thiobarbituric acid reactive substances (TBARS) concentration in plasma. We demonstrated deficient platelet mitochondrial respiratory chain functions, oxidative phosphorylation (OXPHOS), and electron transfer (ET) capacity with complex I (CI)-linked substrates, and reduced the endogenous platelet coenzyme Q10 (CoQ10) concentration in UC patients. The activity of citrate synthase was decreased in UC patients vs. controls (p = 0.0191). γ-tocopherol, α-tocopherol in platelets, and ß-carotene in plasma were significantly lower in UC patients (p = 0.0019; p = 0.02; p = 0.0387, respectively), whereas the plasma concentration of TBARS was increased (p = 0.0022) vs. controls. The changes in platelet mitochondrial bioenergetics are consistent with cell metabolism reprogramming in UC patients. We suppose that increased oxidative stress, decreased OXPHOS, and a reduced platelet endogenous CoQ10 level can contribute to the reprogramming of platelet mitochondrial OXPHOS toward the activation of glycolysis. The impaired mitochondrial function can contribute to increased oxidative stress by triggering the reverse electron transport from the CoQ10 cycle (Q-junction) to CI.


Assuntos
Plaquetas/metabolismo , Metabolismo Energético , Mitocôndrias/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/metabolismo , Contagem de Células Sanguíneas , Estudos de Casos e Controles , Respiração Celular , Citrato (si)-Sintase/metabolismo , Ácidos Graxos/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Diagnostics (Basel) ; 10(3)2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32210203

RESUMO

Chronic kidney disease (CKD) is characterized by a progressive loss of renal function and a decrease of glomerular filtration rate. Reduced mitochondrial function, coenzyme Q10 (CoQ10), and increased oxidative stress in patients with CKD contribute to the disease progression. We tested whether CoQ10 levels, oxidative stress and platelet mitochondrial bioenergetic function differ between groups of CKD patients. METHODS: Twenty-seven CKD patients were enrolled in this trial, 17 patients had arterial hypertension (AH) and 10 patients had arterial hypertension and diabetes mellitus (AH and DM). The control group consisted of 12 volunteers. A high-resolution respirometry (HRR) method was used for the analysis of mitochondrial bioenergetics in platelets, and an HPLC method with UV detection was used for CoQ10 determination in platelets, blood, and plasma. Oxidative stress was determined as thiobarbituric acid reactive substances (TBARS). RESULTS: Platelets mitochondrial respiration showed slight, not significant differences between the groups of CKD patients and control subjects. The oxygen consumption by intact platelets positively correlated with the concentration of CoQ10 in the platelets of CKD patients. CONCLUSION: A decreased concentration of CoQ10 and oxidative stress could contribute to the progression of renal dysfunction in CKD patients. The parameters of platelet respiration assessed by high-resolution respirometry can be used only as a weak biological marker for mitochondrial diagnosis and therapy monitoring in CKD patients.

11.
Can J Physiol Pharmacol ; 98(1): 29-34, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31536712

RESUMO

Mitochondria are the major source of cellular energy metabolism. In the cardiac cells, mitochondria produce by way of the oxidative phosphorylation more than 90% of the energy supply in the form of ATP, which is utilized in many ATP-dependent processes, like cycling of the contractile proteins or maintaining ion gradients. Reactive oxygen species (ROS) are by-products of cellular metabolism and their levels are controlled by intracellular antioxidant systems. Imbalance between ROS and the antioxidant defense leads to oxidative stress and oxidative changes to cellular biomolecules. Molecular hydrogen (H2) has been proved as beneficial in the prevention and therapy of various diseases including cardiovascular disorders. It selectively scavenges hydroxyl radical and peroxynitrite, reduces oxidative stress, and has anti-inflammatory and anti-apoptotic effects. The effect of H2 on the myocardial mitochondrial function and coenzyme Q levels is not well known. In this paper, we demonstrated that consumption of H2-rich water (HRW) resulted in stimulated rat cardiac mitochondrial electron respiratory chain function and increased levels of ATP production by Complex I and Complex II substrates. Similarly, coenzyme Q9 levels in the rat plasma, myocardial tissue, and mitochondria were increased and malondialdehyde level in plasma was reduced after HRW administration. Based on obtained data, we hypothesize a new metabolic pathway of the H2 effect in mitochondria on the Q-cycle and in mitochondrial respiratory chain function. The Q-cycle contains three coenzyme Q forms: coenzyme Q in oxidized form (ubiquinone), radical form (semiquinone), or reduced form (ubiquinol). H2 may be a donor of both electron and proton in the Q-cycle and thus we can suppose stimulation of coenzyme Q production. When ubiquinone is reduced to ubiquinol, lipid peroxidation is reduced. Increased CoQ9 concentration can stimulate electron transport from Complex I and Complex II to Complex III and increase ATP production via mitochondrial oxidative phosphorylation. Our results indicate that H2 may function to prevent/treat disease states with disrupted myocardial mitochondrial function.


Assuntos
Hidrogênio/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ubiquinona/análogos & derivados , Animais , Antioxidantes/farmacologia , Complexo I de Transporte de Elétrons/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredução/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/metabolismo
12.
Gen Physiol Biophys ; 38(4): 325-334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31241044

RESUMO

Seasonal variations in temperature may influence the physiological and pathological metabolic pathways, concentrations of antioxidants, degree of oxidative stress and mitochondrial function. The aim of this study was to evaluate platelet mitochondrial function in human subjects during seasonal variations in temperature. Two groups of healthy young subjects were enroled in the study. Winter group, mean outside temperature was 4.77°C and Spring group, mean outside temperature was 24.32°C. High-resolution respirometry method was used for determination of mitochondrial respiration and oxidative phosphorylation in platelets. Concentrations of coenzyme Q10 (CoQ10) and tocopherols were determined in platelets, blood and plasma. Our data showed slightly (not significantly) reduced respiration in intact platelets, basal and ADP-stimulated mitochondrial respiration at Complex I, as well as CoQ10-TOTAL and α-tocopherol concentrations in winter. The concentration of γ-tocopherol was higher in winter. Platelet mitochondrial ATP production depended on platelet CoQ10-TOTAL concentration in winter, not in spring. We conclude that seasonal temperature participates in the mechanism of platelet mitochondrial respiratory chain function and oxidative phosphorylation that depends on their CoQ10-TOTAL concentration at lower winter outside temperature. CoQ10 supplementation may improve platelets mitochondrial ATP production at winter season. High-resolution respirometry offers sensitive method for detection of changes of platelets mitochondrial respiratory function.


Assuntos
Plaquetas/citologia , Mitocôndrias/fisiologia , Estações do Ano , Ubiquinona/análogos & derivados , Antioxidantes/análise , Plaquetas/metabolismo , Humanos , Ubiquinona/sangue
14.
Med Biol Eng Comput ; 53(12): 1361-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26607818

RESUMO

This work aimed to evaluate the use of a four-point glucagon stimulation test of C-peptide effect on glucose utilization in type 1 diabetic patients using a new mathematical model. A group of 32 type 1 diabetic patients and a group of 10 healthy control subjects underwent a four-point glucagon stimulation test with blood sampling at 0, 6, 15 and 30 min after 1 mg glucagon bolus intravenous administration. Pharmacokinetic and pharmacokinetic/pharmacodynamic models of C-peptide effect on glucose utilization versus area under curve (AUC) were used. A two-sample t test and ANOVA with Bonferroni correction were used to test the significance of differences between parameters. A significant difference between control and patient groups regarding the coefficient of whole-body glucose utilization and AUC C-peptide/AUC glucose ratio (p â‰ª 0.001 and p = 0.002, respectively) was observed. The high correlation (r = 0.97) between modeled coefficient of whole-body glucose utilization and numerically calculated AUC C-peptide/AUC glucose ratio related to entire cohort indicated the stability of used method. The short-term four-point glucagon stimulation test allows the numerically calculated AUC C-peptide/AUC glucose ratio and/or the coefficient of whole-body glucose utilization calculated from model to be used to diagnostically identify type 1 diabetic patients.


Assuntos
Glicemia/metabolismo , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Glucagon/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Glucagon/administração & dosagem , Teste de Tolerância a Glucose , Humanos , Masculino , Modelos Estatísticos , Adulto Jovem
15.
Endocr Res ; 40(3): 156-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25531505

RESUMO

PURPOSE/AIM: The main aim of this study was to propose a method to express whole body insulin sensitivity as estimated by a hyperinsulinemic-euglycemic clamp (HEC) as a dimensionless parameter. MATERIALS AND METHODS: Two groups of subjects were examined: The first group was comprised of seven healthy lean volunteers with BMI <25 kg/m(2) and a second group comprised of four obese subjects with BMI ≥30 kg/m(2). The dependence between the M/I index expressing the whole body insulin sensitivity, and the dimensionless whole human body effect E as a ratio of the clearance of glucose and the clearance of insulin after their exogenous administration during the last 40 min of the HEC test, was expressed by regression analysis. Unlike an expression of insulin sensitivity/resistance as a function of M taking into account the space corrections or the M/I index, our whole human body effect represents the insulin sensitivity/resistance as a dimensionless number. RESULTS: A linear dependence between the M/I index and the dimensionless effect E with zero intercept and slope at 2.2623 ± 0.157, r = 0.914, and between the M/I index and the effect E recalculated per kg of human body weight with zero intercept and slope at 0.03164 ± 0.00127, r = 0.978, were observed. CONCLUSIONS: The high correlation between the M/I index and new effect E in lean and obese volunteers confirms our proposal that the HEC test could be evaluated by a dimensionless parameter which eliminates potential unit mismatches in the expression of clamp results.


Assuntos
Glicemia/metabolismo , Técnica Clamp de Glucose/métodos , Resistência à Insulina/fisiologia , Insulina/sangue , Obesidade/metabolismo , Adulto , Índice de Massa Corporal , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino
16.
Comput Methods Programs Biomed ; 107(2): 347-56, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22465640

RESUMO

New mathematical models from physiologically interpreted parameters capable of evaluating glucose metabolism within the liver and/or the whole body were developed. The group of pigs in a fasting state and the group of pigs with euglycemic supraphysiological hyperinsulinemia were scanned by positron emission tomography after a single dose of [(18)F]FDG tracer. Simultaneously frequent sampling of the dynamic data of [(18)F]FDG plasma concentration in artery, portal vein and hepatic vein was obtained. A system approach to the liver and/or the whole-body system by the tools of linear dynamic sysztem theory was used. Three kinds of structural models, single input and single output or multiple outputs and multiple inputs and single output, were identified. Differences between the group of fasting pigs and the group of pigs in euglycemic supraphysiological hyperinsulinemia were identified by estimated parameters of the structural models. The suitability of the structural mathematical models for the estimation of physiologically interpreted parameters from PET was validated.


Assuntos
Fluordesoxiglucose F18/farmacologia , Glucose/metabolismo , Hiperinsulinismo/metabolismo , Fígado/metabolismo , Modelos Biológicos , Tomografia por Emissão de Pósitrons/métodos , Simulação por Computador , Jejum/metabolismo , Técnica Clamp de Glucose , Humanos , Hiperinsulinismo/diagnóstico por imagem , Compostos Radiofarmacêuticos
17.
Int J Pharm ; 380(1-2): 89-95, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19596057

RESUMO

The study was conducted to exemplify an approach capable of obtaining a new insight into bioequivalence (BE) assessment, by the use of a physiologically motivated model. Data from an oral BE study of two piroxicam (PXM) products was used as an example. The BE study was carried out with 24 healthy European subjects according to a two-sequence crossover-randomized design. The test and reference formulations were a PXM generic formulation (LaborMed Pharma, Romania) and Feldene (Pfizer, USA), respectively. Plasma concentrations of PXM were monitored by a validated high-performance liquid chromatography over a period of 144 h after administration. After the structure of the optimal model was selected, parameters that characterized the whole-body disposition behavior of PXM in the subjects were derived. The paired Student's t-test and Wilkoxon's test were performed on the derived parameters. The null hypothesis of no differences in the parameters of the whole-body disposition behavior of PXM related to the test and reference product was not rejected at 5% level of significance. This result suggested that the compared products were bioequivalent and could be used interchangeably in clinical setting. The presented approach might show a new way, worth incorporating in future BE guidelines.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Medicamentos Genéricos/farmacocinética , Modelos Biológicos , Piroxicam/farmacocinética , Equivalência Terapêutica , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/sangue , Estudos Cross-Over , Humanos , Masculino , Pessoa de Meia-Idade , Piroxicam/sangue
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