RESUMEN
In the past decade, mass spectrometry studies of skeletal muscles have become common. In this tissue, the abundance of several contractile proteins significantly limits the depth of the panoramic proteome analysis. The use of isobaric labels allows improving assessment of the changes in the protein content, while analyzing up to 10 samples in a single run. Here we present the results of a comparative study of various methods for the fractionation of skeletal muscle peptides labeled with an isobaric label iTRAQ. Samples from m. vastus lateralis of eight young males were collected with a needle biopsy. After digestion into peptides and labeling, the preparations were carried out according to three different protocols: (1) peptide purification, HPLC-MS/MS; (2) peptide purification, isoelectric focusing, HPLC-MS/MS; (3) high pH reverse-phase LC fractionation, HPLC-MS/MS. Fractionation of labeled peptides by high pH reverse-phase LC was the optimal strategy for increasing the depth of the proteome analysis. This approach, in addition to contractile and mitochondrial proteins, allowed us to detect a variety of regulatory molecules, including the nucleic acids binding the proteins, chaperones, receptors, and transcription factors.
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Métodos Analíticos de la Preparación de la Muestra/métodos , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Proteoma/análisis , Proteómica/métodos , Coloración y Etiquetado/métodos , Humanos , Focalización Isoeléctrica , Proteoma/química , Espectrometría de Masas en TándemRESUMEN
A large body of experimental data have shown that aerobic exercise of different duration, intensity, and pattern affect molecular mechanisms regulating mitochondrial biogenesis in skeletal muscles. This review focuses on the effects of exercise duration and intensity on the molecular mechanisms of mitochondrial biogenesis regulation in skeletal muscles, namely PGC-1α-dependent signaling. Studies of the effects of acute exercise and exercise training showed that an increase in the duration of aerobic exercise from 30 to 90 min does not provide additional stimuli to activate signaling pathways regulating post-translational modification of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and expression of the PGC-1α gene (PPARGC1A). Conversely, exercise intensity substantially affects mitochondrial biogenesis due to the increase in the recruitment of type II muscle fibers with accompanying pronounced metabolic shift leading to the activation of signaling cascades and expression of genes regulating mitochondrial biogenesis. Therefore, intermittent exercise, which recruits type II muscle fibers, is more efficient in the activation of mitochondrial biogenesis than work-matched continuous exercise. In skeletal muscle adapted to aerobic training, intensity-dependent activation of mitochondrial biogenesis after acute exercise is associated primarily with the AMP-activated protein kinase/PGC-1α pathway, expression of PGC-1α-regulated genes, and expression of PPARGC1A from the alternative (distal) inducible promoter regulated by the cAMP response element-binding protein 1-related transcription factors and their coactivators. Elucidation of the effects of duration and intensity of aerobic exercise on the PGC-1α-dependent and -independent mechanisms of mitochondrial biogenesis is important for treatment of patients with various metabolic disorders, as well as for optimization of training in athletes.
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Contracción Muscular/fisiología , Músculo Esquelético/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Ejercicio Físico , Humanos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genéticaRESUMEN
We tested the hypothesis that strength exercise after intermittent aerobice exercise might activate signalling pathways related to mitochondrial biogenesis (phosphorylation level of AMPK, p38; expression of PGC-1a, NT-PGC-la, TFAM, VEGFA), to protein synthesis (phosphorylation level of p70S6Kl(Thr389) eEF2(Thr56) expression of IGF-lEa, IGF-lEc (MGF), REDDl) and to proteolysis (phosphorylation level of FOXOl(Ser256) and expression of MURFl, MAFbx, Myostatin) in trained skeletal muscle. Nine amateur endurance-trained athletes performed 70-Min bicycle intermittent exercise with both legs (E), followed by one-leg strength exercise (ES: 4 bouts of knee extensions at 75% MVC till exhaustion). Gene expression and protein level were evaluated in samples from m. vastus lateralis before, 40 min, 5 and 22 h after the aerobic exercise. The phosphorylation level of the ACC(Ser79/222)(an endogenous marker of AMPK activity) and expression of PGC-la-related TFAM - marker of mitochondrial biogenesis were increased after E exercise and did not changed after ES. Expression of PGC-lα and truncated isoform NT- PGC-lα was increased in both legs as well. Insulin concentration in blood was dramatically, 7.5-fold diminished after intermittent aerobic exercise. Phosphorylation of FOXO(Ser256) - regulator of ubiquitin-related proteolysis - was decreased after both E and ES exercise, it means it was activated in both cases, while expression of E3-ubiquitin ligase MURFl was increased only after E exercise. Both aerobic and combined exercise did not affect regulation of protein synthesis: neither expression of IGF-lEa and IGF-Ec (MGF) mRNA isoforms nor phosphorylation levels of markers of protein synthesis p70S6Kl(Thr389) and eEF2(Thr56) were changed. Thus effects of aerobic exercise in trained muscles are noticeably suppressed by performing strength exercise immediately after endurance one. In particular, the activity of signalling cascades and expression of genes regulating mitochondrial biogenesis are lessened, but protein synthesis regulation is not affected. And at last strength exercise suppresses induced by aerobic exercise expression of MURF1 gene - marker of ubiquitin proteasome system. It means that strength exercise just after intermittent aerobic exercise might have a negative effect on aerobic performance if used chronically.
Asunto(s)
Ejercicio Físico , Músculo Esquelético , Biogénesis de Organelos , Biosíntesis de Proteínas , Atletas , Ejercicio Físico/fisiología , Regulación de la Expresión Génica , Humanos , Músculo Esquelético/metabolismo , Proteínas/metabolismoRESUMEN
A method to evaluate aerobic-anaerobic transition (AAT) during exercise is suggested. The subjects performed two tests with incremental increase of load: bicycle exercise and one leg knee extensions. In both tests the relation of deoxygenated hemoglobin (HHb) to EMG-activity of m. vastus lateralis during test has characteristic peak corresponding to AAT. The statistically significant correlation (r = 0.78, p < 0.05) between the load corresponding to AAT and anaerobic threshold (blood [La] = 4 mmol) was found during bicycle test. The method is applicable to determination of AAT during exercise of small muscle group.
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Umbral Anaerobio/fisiología , Músculo Esquelético/fisiología , Adolescente , Adulto , Humanos , Masculino , Espectrofotometría InfrarrojaRESUMEN
Adaptation of skeletal muscles to physical training depends on intensity and duration of exercise sessions. The purpose of this study was to investigate the effect of the duration of moderately intensive single aerobic exercise session (60% V(O2max)) on the activation of signalling kinases which regulate PGC-1α gene expression and on the expression of regulatory genes of mitochondrial biogenesis and muscle catabolism. Nine athletes (V(O2max)) 59 mL/min/kg) performed 30-, 60-, and 90-min cycling sessions. An exercise-induced increase in PGC-1α gene expression was proved to occur without activation of AM PK, p38 MAPK and CAMKII. It was found that 60- and 90-min sessions result in comparable increases of PGC-lα gene expression, while VEGFA gene expression increased only after 90-min session. Even 90-min exercise did not induce the activation of FOXO1-E3 ubiquitin ligase pathway and did not result in an increase of expression of exercise-induced catabolic genes.
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Ejercicio Físico/fisiología , Expresión Génica/fisiología , Proteínas Mitocondriales/biosíntesis , Músculo Esquelético , Resistencia Física/fisiología , Factores de Transcripción/genética , Prueba de Esfuerzo , Humanos , Masculino , Proteínas Mitocondriales/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Factores de TiempoRESUMEN
It is well known that metabolic, cardiovascular and respiratory indices during exercise of moderate intensity are linearly related to exercise power. After the load reaches the definite level this relationship changes for nonlinear. Different methods of evaluating the intensity of load at which this transition takes place are discussed. The methods for investigation of transient process dynamics in energy supply of muscle contractions with changing intensity of contractions is described. The dependence of dynamic characteristics of physiological indices from fitness level and in its turn from age and level of physical activity is discussed.
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Metabolismo Energético/fisiología , Ejercicio Físico , Consumo de Oxígeno/fisiología , Aptitud Física , Aerobiosis , Anaerobiosis , Frecuencia Cardíaca/fisiología , Humanos , Contracción Muscular/fisiologíaRESUMEN
Hypertrophic effect of strength training is known to originate from mechanical and metabolic stimuli. During exercise with restricted blood supply ofworking muscles, that is under conditions of intensified metabolic shifts, training effect may be achieved with much lower external loads (20% of one repetition maximum (1 RM)). The aim of the study was to compare the effects of 8 wks high-intensity (80-85% MVC) strength training and low-intensity (50% 1 RM) training without relaxation. The high-intensity strength training leads to somewhat higher increments in strength and size of trained muscles than training without relaxation. During high-intensity training an increase of area occupied by type II fibers at muscle cross section prevails while during training without relaxation - an increase of area occupied by type I fibers takes place. An exercise session without relaxation leads to a more pronounced increase in secretion of growth hormone, IGF-1 and cortisol. Expression of gene regulating myogenesis (Myostatin) is changed in different ways after high-intensity strength exercise session and after exercise session without relaxation. Low-intensity strength training (50% 1 RM) without relaxation is an effective way for inducing increases of strength and size of trained muscles. This low intensive type of training may be used in restorative medicine, sports and physical culture.
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Desarrollo de Músculos/fisiología , Relajación Muscular/fisiología , Fuerza Muscular/fisiología , Entrenamiento de Fuerza , Femenino , Humanos , MasculinoRESUMEN
Oxygen delivery to muscle, its consumption and glycolytic flux, all of each affect and restrict aerobic performance, are discussed. Energy supply of intensive exercise till exhaustion lasting 3 to 4 min is provided mainly by oxidative metabolism, simultaneously glycolytic flux may be increased considerably. Other conditions being equal, capacity of oxygen delivery determines oxygen partial pressure in myoplasm of exercising/contracting muscle. With PO2 in myoplasm increasing from 0 to 1-2 mm Hg oxygen consumption (VO2) in mitochondria enhances dramatically, with further increase of PO2 its rise slows down. At the ascending part of VO2-PO2 relationship for mitochondria the increase of VO2 is noticeably restricted by oxygen delivery to contracting muscle. When PO2 approaches plateau of the VO2-PO2 relationship, an increase of VO2 is restricted by mitochondria capacity to accumulate oxygen and augmented oxygen delivery will not lead to a significant increase of muscle VO2. On the other hand considerable accumulation of glycolytic metabolites in contracting muscle causes a decrease of contractility which in its turn may restrict aerobic performance. Noteworthy no strict relationship between glycolytic flux and PO2 in myoplasm exists. That is why correct evaluation of factors limiting aerobic performance presupposes simultaneous evaluation of both glycolytic flux and oxygen consumption in muscle which in its turn depends on oxygen delivery to mitochondria and its utilization.
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Ejercicio Físico/fisiología , Contracción Muscular/fisiología , Músculos/metabolismo , Consumo de Oxígeno/fisiología , Oxígeno/sangre , Glucólisis/fisiología , Humanos , Ácido Láctico/metabolismo , Mitocondrias/metabolismo , Mitocondrias/fisiología , Músculos/fisiología , Oxígeno/metabolismo , Fenómenos Fisiológicos RespiratoriosRESUMEN
The results of evaluation of the efficacy of alpha1-adrenoblockers in treatment of ureteral calculi are presented. Comparative, prospective, placebo-uncontrolled nonrandomized single-center study was performed, which included 118 patients with solitary diagnosed calculi in various parts of ureter. After the pain relief, all the patients underwent conservative therapy aimed at spontaneous discharge of concretions. The maximum duration of conservative treatment was 28 days. Ultrasound monitoring was performed every week in all patients. The control group of patients received only Drotaverinum 40 mg three times a day, and analgesics. The main group received alpha1-adrenoblocker tamsulosin at a standard dose of 0.4 mg once a day along with Drotaverinum and analgesics. The overall probability of a discharge of concrements localized in the distal ureter was significantly (P = 0.02) higher in the patients treated with alpha1-adrenoblockers. Treatment regimen in main group of patients allowed better control of pain during all periods of observation, even if the discharge of concretions was not registered. The overall probability of migration of concrements from the proximal to the distal ureter in main group of patients was 52% versus 32% in controls (P = 0.17). The frequency of adverse effects was comparable in both groups. Vertigo, postural hypotension, and weakness were significantly more frequent in the main group of patients. Univariate and multivariate analyses of the proportional hazards model have demonstrated that the administration of alpha1-adrenoblocker increased the likelihood of a discharge of concrement from the distal ureter. It is shown that the nature of the applied therapy has directly influence on the risk of an earlier discharge of concretions. Inclusion of alpha1-adrenoblockers in the treatment scheme increased the probability of discharge of concrements at 4.11 times.
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Antagonistas de Receptores Adrenérgicos alfa 1/administración & dosificación , Sulfonamidas/administración & dosificación , Cálculos Ureterales/tratamiento farmacológico , Antagonistas de Receptores Adrenérgicos alfa 1/efectos adversos , Analgésicos/administración & dosificación , Analgésicos/efectos adversos , Femenino , Humanos , Masculino , Papaverina/administración & dosificación , Papaverina/efectos adversos , Papaverina/análogos & derivados , Estudios Prospectivos , Sulfonamidas/efectos adversos , Tamsulosina , Factores de Tiempo , Cálculos Ureterales/fisiopatologíaRESUMEN
Recently there was a tendency to increase usage of double poling during cross country skiing and accordingly to increase loading of the arm muscles. The aim of the study was to compare the aerobic performance of cross country skiers in the incremental double poling and running tests till exhaustion. Eight junior subnational level cross country skiers ( V(O)2max 70 (66-72) ml/min/kg) have participated in the study. The rate of blood lactate increase during double poling test was higher than during running test. Double poling V(O)2peak was 88 (84-93)% from running V(O)2max. Relative anaerobic threshold (% V(O)2max at AT), closely linked to the current aerobic performance, was substantially lower in double poling test compared with running test: 79 (57-83)% and 94 (90-98)% respectively. We suggest that the main reserve for further increase of aerobic performance of cross country skiers lies in an increase of double poling aerobic capacity.
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Umbral Anaerobio/fisiología , Brazo/fisiología , Pierna/fisiología , Músculo Esquelético/fisiología , Esquí/fisiología , Adulto , Atletas , Humanos , MasculinoRESUMEN
The aim of the study was to investigate allele and genotype distributions of the muscle-specific creatine kinase gene (CKMM) A/G polymorphism in athletes (n = 384) and controls (n = 1116), and to find interrelation between genotypes and aerobic capacity in rowers (n = 85). Genotyping was performed by restriction fragment length polymorphism analysis. Aerobic capacity (maximal oxygen consumption (VO2(max)) and maximal power production capacity (W(max was determined using an incremental test to exhaustion by rower ergometer. The frequencies of CKMM A allele and AA genotype were significantly higher in endurance-oriented athletes (n = 176) than in controls (A allele: 78.7% vs. 65.4%; p < 0.0001; AA genotype: 59.7% vs. 44.2%; p = 0.0003). On the other hand, GG genotype was more prevalent in weightlifters (n = 74) in comparison with controls (31.1% vs. 13.4%; p = 0.0001). Furthermore, CKMM AA genotype was associated with high values of VO2(max) (AA - 58.98 (3.44) ml/kg/min, GA - 56.99 (4.36) ml/kg/min, GG - 52.87 (4.32) ml/kg/min, p = 0.0097). Thus, CKMM gene A/G polymorphism is associated with physical performance of athletes.
Asunto(s)
Atletas , Forma MM de la Creatina-Quinasa/genética , Resistencia Física/genética , Polimorfismo Genético , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Consumo de Oxígeno/genéticaRESUMEN
AIM OF THE STUDY: To investigate the efficacy and safety of non-immunogenic staphylokinase (NS) compared with alteplase (A) in patients with acute ischemic stroke (AIS) within 4.5 h after symptom onset. MATERIAL AND METHODS: 336 patients with IS within 4.5 h after symptom onset were included in a randomized, open-label, multicenter, parallel-group, non-inferiority comparative trial of NS vs A (168 patients in each group). NS was administered as an intravenous bolus in a dose of 10 mg, regardless of body weight, over 10 s, A was administered as a bolus infusion in a dose of 0.9 mg/kg, maximum 90 mg over 1 hour. The primary efficacy endpoint was a favorable outcome, defined as a modified Rankin scale (mRS) score of 0-1 on day 90. Safety endpoints included all-cause mortality on day 90, symptomatic intracranial haemorrhage, and other serious adverse events (SAEs). RESULTS: At day 90, 84 (50%) patients reached the primary endpoint (mRS 0-1) in the NS group, 68 (41%) patients - in the A group (p=0.10, OR=1.47, 95% CI=0.93-2.32). The difference between groups NS and A was 9.5% (95% CI= -1.7-20.7) and the lower limit of the 95% CI did not cross the margin of non-inferiority (pnon-inferiority<0.0001). There were no significant differences in the frequency of deaths between the groups: on day 90, 17 (10%) patients in the NS group and 24 (14%) in the A group had died (p=0.32). There was a trend towards significant differences in the frequency of symptomatic intracranial haemorrhage: NS group - 5 (3%) patients, A group - 13 (8%) patients (p=0.087, OR=0.37, 95% CI=0.1-1.13). There were significant differences in the number of patients with SAEs: in the NS group - 22 (13%) patients, in the A group - 37 (22%) patients (p=0.044, OR=0.53, 95% CI=0.28-0.98). CONCLUSION: The presented results of the FRIDA trial are the first in the world to use a drug based on NS in patients with IS. It has been shown that a single bolus (within 10 s) administration of NS at a standard dose of 10 mg, regardless of body weight, allows to conduct fast, effective and safe thrombolytic therapy in patients with IS within 4.5 h after symptom onset. In further clinical tials of NS, it is planned to expand the therapeutic window beyond 4.5 h after symptom onset in patients with IS.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Metaloendopeptidasas , Accidente Cerebrovascular , Peso Corporal , Isquemia Encefálica/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Humanos , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/complicaciones , Metaloendopeptidasas/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/etiología , Terapia Trombolítica , Resultado del TratamientoRESUMEN
At the turn of the millennium, a new generation of lipid nanoparticles for pharmacology was developed, nanostructured lipid carriers (NLC). The features of NLC structure which allow the inclusion of natural biologically active lipids in the NLC matrix open a wide prospect for the creation of high performance drug carriers. In this study NLC formulations were developed based on natural lipids from the Siberia region (Russia): fish oil from Lake Baikal fish; polyunsaturated fatty acid fractions and monounsaturated and saturated fatty acid fractions from fish oil and Siberian pine seed oil. Formulation parameters of NLC such as as type of surfactant and storage conditions were evaluated. The data obtained indicated high physical stability of NLC formulated on the basis of pure fish oil stabilized by Tween 80 and NLC formulated on the basis of free fatty acids stabilized by Poloxamer 188. The good chemical stability of the lipid matrix and the high concentrations of the biologically active polyunsaturated fatty acids in the NLC developed open wide prospects for their use in pharmaceutics and cosmetics.
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Portadores de Fármacos/química , Lípidos/química , Liposomas/química , Nanoestructuras/química , Rastreo Diferencial de Calorimetría , Almacenaje de Medicamentos , Electroquímica , Ácidos Grasos/química , Ácidos Grasos Insaturados/química , Aceites de Pescado/química , Tamaño de la Partícula , Poloxámero , Polisorbatos , Siberia , Tensoactivos , TemperaturaRESUMEN
Continuous wavelet analyses was applied to investigate the spectral characteristics of m. vastus lateralis EMG activity in two incremental tests till exhaustion: rhythmic knee-joint extensions and cycling. Wavelet analysis of surface EMG revealed differences in the dynamics of time-frequency characteristics of the signal during single cycle of two types of movements with different loads, as well as differences in the slow variations of spectral characteristics associated with the development of muscle fatigue during the tests. It was shown that during cycling with low loads (beginning of the test) maximum of EMG activity was confined within the second half of muscle contraction (the angle in the knee joint approximately 140 degrees), increase of load at the end of the test led to a shift of the peak to the beginning of the active phase of movement, while the median frequency of the "instant" wavelet spectra during muscle contraction remained almost unchanged. During knee-joint extensions the maximum of EMG activity was observed at the end of the active phase of movement for all loads, median frequency increased significantly with increasing the angle at the knee joint. Long-term dynamics of EMG intensity growth during these tests differed as well, whereas dynamics of wavelet-spectra median frequencies were practically the same--during both tests their growths were observed.
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Ciclismo/fisiología , Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Articulación de la Rodilla/fisiología , Contracción Muscular/fisiología , Músculo Cuádriceps/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Análisis de OndículasRESUMEN
Bacteriophage enzyme preparations exolysin and endolysin were studied. Exolysin (a phage-associated enzyme) was obtained from tail fraction and endolysin from phage-free cytoplasmic fraction of disintegrated Salmonella enteritidis cells. A new method for purification of these enzymes was developed, and their molecular masses were determined. The main catalytic properties of the studied enzymes (pH optimum and specificity to bacterial substrates) were found to be similar. Both enzymes lyse Escherichia coli cells like chicken egg lysozyme, but more efficiently lyse S. enteritidis cells and cannot lyse Micrococcus luteus, a good substrate for chicken egg lysozyme. Similar properties of exolysin and endolysin suggest that these enzymes are structurally similar or even identical.
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Endopeptidasas/química , Fagos de Salmonella/enzimología , Proteínas Virales/química , Animales , Biocatálisis , Pollos , Endopeptidasas/aislamiento & purificación , Endopeptidasas/metabolismo , Escherichia coli/metabolismo , Muramidasa/metabolismo , Salmonella enteritidis/efectos de los fármacos , Especificidad por Sustrato , Proteínas Virales/aislamiento & purificación , Proteínas Virales/metabolismoRESUMEN
OBJECTIVE: The functional 577R allele of the alpha-actinin-3 (ACTN3) gene has been reported to be associated with elite power athlete status, while the nonfunctional 577XX genotype (predicts an alpha-actinin-3 deficient phenotype) has been hypothesised as providing some sort of advantage for endurance athletes. In the present study, the distribution of ACTN3 genotypes and alleles in Russian endurance-oriented athletes were examined and association between ACTN3 genotypes and the competition results of rowers were sought. METHODS: 456 Russian endurance-oriented athletes of regional or national competitive standard were involved in the study. ACTN3 genotype and allele frequencies were compared with 1211 controls. The data from the Russian Cup Rowing Tournament were used to search for possible association between the ACTN3 genotype and the long-distance (approximately 6 km) rowing results of 54 athletes. DNA was extracted from mouthwash samples. Genotyping for the R577X variant was performed by PCR and restriction enzyme digestion. RESULTS: The frequencies of the ACTN3 577XX genotype (5.7% vs 14.5%; p<0.0001) and 577X allele (33.2% vs 39.0%; p = 0.0025) were significantly lower in endurance-oriented athletes compared with the controls, and none of the highly elite athletes had the 577XX genotype. Furthermore, male rowers with ACTN3 577RR genotype showed better results (1339 (11) s) in long-distance rowing than carriers of 577RX (1386 (12) s) or 577XX (1402 (10) s) genotypes (p = 0.016). CONCLUSION: Our data show that the ACTN3 577X allele is under-represented in Russian endurance athletes and is associated with the rowers' competition results.
Asunto(s)
Actinina/genética , Resistencia Física/genética , Polimorfismo Genético/genética , Deportes , Adulto , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Masculino , FenotipoRESUMEN
Nanostructured lipid carriers (NLC) are new drug systems composed of physiological lipid materials. The possibility of including different types of lipids into the NLC structure revealed the wide prospects for using biologically active natural oils for the development of the cutaneous preparations. In this study the formulation parameters of NLC on the basis of Siberian pine seed oil were evaluated including concentration of lipids, types of surfactants and storage conditions (4 degrees C, 20 degrees C, 40 degrees C). Size distribution and storage stability of formulations produced by hot high pressure homogenisation were investigated by laser diffractometry and photon correlation spectroscopy. The NLC were characterised by their melting behaviour using differential scanning calorimetry. The obtained data indicated the high physical stability of the developed NLC formulations.
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Portadores de Fármacos/química , Lípidos/química , Nanopartículas/química , Pinus/química , Aceites de Plantas/química , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Ácidos Grasos/química , Tamaño de la Partícula , Poloxámero , TensoactivosRESUMEN
The aim of the study was to check the hypothesis that elite endurance athletes (junior and national team) show the decreased final blood lactate concentration after incremental test till exhaustion with increased aerobic performance level. 20 physical active men and 45 elite middle and long distance endurance athletes (speed skaters, triathletes, cross country skiers) participated in the study. Significant negative correlations (r = -0.59--0.87) were found between final blood lactate concentration after incremental test till exhaustion and aerobic performance (anaerobic threshold (AT)) for athletes groups and not for physically active subjects. Moreover the less final blood lactate concentration and more VO2 at AT have elite speed skates, the higher volume of type I muscle fibers in working muscle they have (r = -0.84 and r = 0.7, accordingly).
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Umbral Anaerobio/fisiología , Ejercicio Físico/fisiología , Ácido Láctico/sangre , Atletas , Humanos , Masculino , Adulto JovenRESUMEN
The aim of the study was to investigate allelic distribution of the mitochondrial transcription factor gene (TFAM) Ser12Thr polymorphism in athletes (n = 1537) and controls (n = 1113), and to find interrelation between genotypes and aerobic capacity in rowers (n = 90). Genotyping was performed by restriction fragment length polymorphism analysis. Aerobic capacity (maximal oxygen consumption (VO2max) and maximal power production capacity (Wmax)) was determined using an incremental test to exhaustion by rower ergometer. The frequency of TFAM 12Thr allele was significantly higher in endurance-oriented athletes (n = 588) than in controls (14.0% vs. 9.1%; p <0.0001), and increased with the growth of skills. Furthermore, TFAM 12Thr allele was associated with high values of aerobic performance (when Wmax and VO2max were measured). Thus, TFAM gene Ser12Thr polymorphism is associated with physical performance of athletes.