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1.
Int J Sports Med ; 43(7): 625-631, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35108730

RESUMEN

The use of dual-energy X-ray absorptiometry (DXA) may be invalid for assessing athletes with larger bodies, larger lean body mass, and thicker trunks. This study compared the athletes' visceral adipose tissue (VAT) assessed using DXA and magnetic resonance imaging (MRI). Eighty-two Japanese male collegiate athletes from 18 sports participated in this study. VAT was assessed using the dual-energy scan that coincided with the 4th lumbar vertebra. The sum of eight magnetic resonance slices corresponding to the region of the dual-energy scan was used for comparison. The VAT volume was higher with the dual-energy scan than with MRI (difference: 35 cm3, p<0.01). A significant correlation was noted between the volumes measured using both modalities (r=0.88, p<0.01). Magnetic resonance-derived volumes less than 600 cm3 showed a stronger significant correlation with dual-energy-derived volumes. However, magnetic resonance-derived VAT volumes exceeding 600 cm3 were not significantly correlated with dual-energy-derived volumes. In conclusion, VAT volumes derived from DXA were larger and significantly correlated with those derived from MRI across a wide range of values. Methods using DXA for assessing the visceral fat volume may require adjustment to estimate abdominal visceral fat volume in athletes, with care taken when using such methods for heavyweight athletes.


Asunto(s)
Grasa Intraabdominal , Imagen por Resonancia Magnética , Absorciometría de Fotón/métodos , Atletas , Índice de Masa Corporal , Humanos , Grasa Intraabdominal/diagnóstico por imagen , Masculino
2.
Phys Act Nutr ; 27(1): 47-54, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37132210

RESUMEN

PURPOSE: Muscle glycogen storage before a race is necessary for endurance athletes to achieve the best performance. Generally, the recommended carbohydrate intake for preparation over 90 min of the race is 10-12 g·kg--1·day--1. However, it remains unclear whether an elite athlete with an already high-carbohydrate diet can further increase muscle glycogen through a very-high-carbohydrate intake. Therefore, we compared the effects of three types of glycogen loading in a 28-year-old male athlete who belongs to the top 50 racewalkers in the world, consuming a daily energy intake of 4507 kcal and a carbohydrate intake of 12.7 g·kg--1·day--1. METHODS: The racewalker consumed very-high-carbohydrate diets three times for 2 days each, 13.7 g·kg--1·day--1 for trial 1, 13.9 g·kg--1·day--1 for trial 2, and 15.9 g·kg--1·day-1 for trial 3. Muscle glycogen concentrations in the anterior (vastus lateralis and vastus intermedius) and posterior thighs (semimembranosus, semitendinosus, and biceps femoris) were measured using carbon-13 magnetic resonance spectroscopy. RESULTS: Muscle glycogen concentrations in both the anterior and posterior thighs increased in all trials, particularly in trial 3. Body mass also increased by 1.5 kg in trials 1 and 2 and by 1.8 kg in trial 3 before and after the trials. The participant felt satiated throughout the day and experienced stomach discomfort during trial 3. CONCLUSION: We found that a 2-day very-high-carbohydrate diet and tapering of training could further increase the muscle glycogen concentration in athletes. However, we speculated that 15.9 g·kg--1·day--1 carbohy.

3.
Front Sports Act Living ; 5: 1188224, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37383062

RESUMEN

The "meal first" strategy is traditionally recommended for athletes' conditioning. However, the importance of the "meal first" principle has not been detailly well documented in athletes' lives. Supplement use has recently become a common part of athletes' diets, but unmonitored supplement use can cause negative consequences, such as anti-doping violations and health issues. Therefore, this review summarizes how the "meal first" strategy and planned supplement use are important for enhancing athletes' health and performance. We believe that the "meal first" strategy is beneficial in terms of the following aspects: (1) consumption of multi-nutrients and other functional components simultaneously; (2) positive effects on psychological well-being; (3) contribution to athletes' health by way of mastication; and (4) less risk for anti-doping violations. Before supplement use, we recommend that athletes first verify their basic factors (e.g., diet, training, and sleep), given that the benefits of supplements are examined and demonstrated with the control of those factors. Otherwise, athletes cannot obtain maximal benefits from the supplements. In contrast, there are situations in which supplements in athletes' lives can be advantageous, such as (1) nutrient deficiency due to ongoing dietary characteristics; (2) interruption of meals due to disease; (3) inaccessibility of quality food during athletic travel; (4) difficulty preparing food due to societal restrictions associated with disasters or infection outbreaks; (5) having a meal before, during, or after exercise is difficult; and (6) achieving targeted intake of performance-enhancing ingredients is not practical. In summary, we emphasize that the "meal first" strategy is recommended for athletes' conditioning, but there are several contexts when supplement use can be more useful in athletes' lives.

4.
Front Sports Act Living ; 5: 1258542, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37927448

RESUMEN

Elite athletes frequently invest in the use of supplements to optimize their dietary regimens and enhance their athletic performance. However, unregulated and unplanned use of supplements can lead to adverse consequences, including anti-doping rule violations or health issues. Thus, athletes should verify their diets, consider scientific evidence, and take necessary precautions regarding supplements before use. To date, no study has explored whether athletes check these factors before using supplements. This study aimed to investigate supplement use using a questionnaire administered to 1,392 athletes (including candidate athletes) who participated in the Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic/Paralympic Games. Participants were categorized as follows: 1,040 participants in the Tokyo 2020 Olympic Games, 83 in the Tokyo 2020 Paralympic Games, 239 in the Beijing 2022 Winter Olympic Games, and 30 in the Beijing 2022 Winter Paralympic Games. We collected data on supplement use and gained further knowledge through interviews with the athletes. Approximately 70% of Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic athletes and approximately 50% of Beijing 2022 Winter Paralympians used supplements. Over 50% of athletes had not received a doctor's diagnosis or a dietitian's evaluation before supplement use. Moreover, only 50% of the athletes who used dietary supplements reviewed the scientific evidence for the dietary supplements before using them and justified their choice based on their own investigation, while those who did not use dietary supplements cited either a lack of need or fear of an anti-doping rule violation. Considering the holistic health and performance of athletes, as well as the risk associated with unregulated use, such as overdose and anti-doping rule violations, there is a need for nutritional education on supplement use for athletes and their entourages.

6.
Sports (Basel) ; 9(6)2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34200082

RESUMEN

The aim of the present study was to clarify the influence of inulin and lactulose-fortified prebiotic food intakes on bone metabolism turnover among Japanese female athletes. The participants included 29 female athletes aged 18-25 years. They were requested to consume their habitual foods or drinks with one pack of prebiotic food every day for 12 weeks. Dietary intake, training time, body composition, blood sample, and fecal microbiota were assessed during this intervention period. Body composition, total energy intake, and training time of the participants revealed no significant changes during the intervention period. The occupation ratio of Bifidobacterium spp. was significantly increased at 3 and 4 weeks (18.0 ± 8.3% and 17.6 ± 8.5%, respectively) compared to that of pre-intervention (11.7 ± 7.3%) (p = 0.019 and p = 0.035, respectively). The serum TRACP-5b level was significantly decreased at 12 weeks (363 ± 112 mU/dL) compared to that at baseline (430 ± 154 mU/dL) (p = 0.018). These results suggest that the prebiotic food used in this study might have beneficial effects on bone health and gut microbial environment among female athletes. Further studies are warranted to identify the mechanism of the prebiotics-gut-bone axis.

7.
Sports (Basel) ; 9(7)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202335

RESUMEN

The Japanese government declared a state of emergency from 7 April to 25 May to limit people's movement due to the coronavirus disease (COVID-19) pandemic. This pandemic negatively affects athletes' body composition due to inactivity. Therefore, we compared the body composition data (i.e., fat-free mass (FFM) and fat mass (FM)), of 43 Japanese elite fencers (22 men, 21 women), in September 2019 for baseline, and of 21 (12 men, 9 women) who completed the following measurements in June 2020 (POST; immediately after rescinding the emergency state) and September 2020 (POST-4M; 4-months after rescinding the emergency state). Results at baseline indicate no significant differences in body compositions among fencing disciplines. We also confirmed no significant changes in body mass during the 1-year investigation period in either sex. There were no time-course changes in men's FFM and FM; however, time-course changes in women's FM were observed. Compared to the baseline, FM values were significantly higher at POST and then returned to baseline levels at POST-4M in women. In conclusion, the 2-month stay-at-home period due to COVID-19 negatively affected women's FM changes, but not their FFM or men's FM.

8.
Hum Reprod ; 24(12): 3172-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19729377

RESUMEN

BACKGROUND: Decreased susceptibility of endometrial tissue to apoptosis may contribute to the pathogenesis of endometriosis. We investigate the role of survivin in the pathophysiology of endometriosis through the ability of ectopic and eutopic endometrial stromal cells (ESCs) to resist apoptosis. METHODS: Ectopic ESCs were obtained from ovarian chocolate cysts in patients undergoing laparoscopic surgery (n = 22). Eutopic ESCs were isolated from endometrial tissue of cyclic premenopausal women undergoing hysterectomy for fibroids (n = 22). Purified stromal cells were studied in vitro. The number of surviving cells and activation of caspases were assessed by WST-8 assay and immunoblotting. Expression of inhibitor of apoptosis proteins (IAP) family members: cIAP1 (birc2), cIAP2 (birc3), XIAP (birc4), survivin (birc5) were examined using cDNA array and real-time RT-PCR. Effects of gene silencing by small inhibitor RNAs (siRNA) were examined by WST-8-assay, Annexin-V staining and immunoblotting. RESULTS: After staurosporine (SS) treatment, 55% of eutopic ESCs survived versus 70% of ectopic ESCs. Procaspase-3 or -7 was more intensely activated by SS treatment in eutopic than in ectopic ESCs (P < 0.01). mRNAs for IAP-family genes, such as cIAP-1, XIAP and survivin, were highly expressed in ectopic ESCs before SS treatment. The fold induction of survivin expression after SS treatment was higher in ectopic than eutopic ESCs (2.8 +/- 0.27 versus 0.69 +/- 0.07, respectively). Survivin gene silencing in SS-treated ectopic ESCs led to an increase of apoptotic cells (P < 0.05, versus control siRNA). CONCLUSIONS: We demonstrated that survivin plays a critical role in susceptibility of ESCs to apoptosis. Our results indicate that a survivin inhibitor may be effective as a novel treatment for endometriosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Endometriosis/fisiopatología , Endometrio/citología , Proteínas Asociadas a Microtúbulos/fisiología , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Silenciador del Gen , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Leiomioma/fisiopatología , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero , ARN Interferente Pequeño , Estaurosporina/farmacología , Células del Estroma/patología , Células del Estroma/fisiología , Survivin
9.
Fertil Steril ; 100(4): 1170-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23876538

RESUMEN

OBJECTIVE: To evaluate the effects of parthenolide on human endometriotic cells and murine endometriotic lesions. DESIGN: Experimental study. SETTING: University hospital and laboratory of animal science. PATIENT(S) AND ANIMAL(S): Twenty women with ovarian endometrioma and 30 mice. INTERVENTION(S): Ectopic endometrial tissue from the endometrioma was collected. MAIN OUTCOME MEASURE(S): Human endometriotic stromal cells (ESCs) were pretreated with parthenolide and exposed to tumor necrosis factor (TNF)-α. Interleukin 8 (IL-8) and COX-2 gene expressions were evaluated by real-time reverse transcription-polymerase chain reaction. Interleukin-8 protein, prostaglandin E2 (PGE2) level, and intranuclear p65 protein concentration were determined by ELISA. Cell proliferation was assessed by 5-bromo-2'-deoxyuridine-ELISA. Phosphorylation of signaling pathways in ESCs was evaluated by Western blotting. Gene expression and proliferative activity in murine endometriosis-like lesions were assessed by real-time reverse transcription-polymerase chain reaction and Ki67 staining, respectively. RESULT(S): With parthenolide pretreatment, TNF-α-induced IL-8 gene and protein expression in ESCs were diminished. Tumor necrosis factor α-induced COX-2 expression and PGE2 synthesis were also inhibited. Adding parthenolide repressed TNF-α-induced 5-bromo-2'-deoxyuridine incorporation and IκB phosphorylation in ESCs. As in vivo experiments, administering parthenolide reduced the number, surface area, and weight, the level of Vegf, Il-6, Mcp-1, and Lif gene expression, and the percentage of Ki67-positive cells in murine endometriosis-like lesions. CONCLUSION(S): Parthenolide repressed the development of endometriosis by suppressing the inflammatory peritoneal environment through the nuclear factor κB pathway.


Asunto(s)
Antiinflamatorios/farmacología , Proliferación Celular/efectos de los fármacos , Dinoprostona/metabolismo , Endometriosis/prevención & control , Endometrio/efectos de los fármacos , Sesquiterpenos/farmacología , Células del Estroma/efectos de los fármacos , Animales , Western Blotting , Células Cultivadas , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Endometriosis/inducido químicamente , Endometriosis/genética , Endometriosis/metabolismo , Endometriosis/patología , Endometrio/metabolismo , Endometrio/patología , Ensayo de Inmunoadsorción Enzimática , Estradiol , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas I-kappa B/metabolismo , Mediadores de Inflamación/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Antígeno Ki-67/metabolismo , Ratones , Ratones Endogámicos BALB C , Fosforilación , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/patología , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
10.
Fertil Steril ; 95(1): 33-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20655525

RESUMEN

OBJECTIVE: To search for the demethylated cytosine-phosphate-guanine (CpG) islands within the aromatase gene in stromal cells derived from endometriotic chocolate cysts. DESIGN: Prospective study. SETTING: Department of Obstetrics and Gynecology and Department of Biosignaling, Tottori University, Yonago, Japan. PATIENT(S): Twenty-eight women who underwent laparoscopy (n=14) and laparotomy (n=14). INTERVENTION(S): Endometrial and endometriotic stromal cells were obtained from the uterus and chocolate cyst lining of the ovary. MAIN OUTCOME MEASURE(S): We searched for the CpG island and examined methylation profile and the association of methyl-binding proteins with the CpG island. RESULT(S): Up-regulation of aromatase messenger RNA (mRNA) expression was demonstrated in endometriotic cells. Three proximal promoters drove the mRNA expression. In endometrial cells, a marginal level of aromatase mRNA expression was observed. Treating endometrial cells with the demethylating agent 5-aza-2'-deoxycytidine markedly enhanced aromatase mRNA expression. The same promoters as in the endometriotic cells were used. To identify the unmethylated CpGs in endometriotic cells, we searched for CpG islands within the aromatase gene and subsequently examined the methylation profiles. Sequence analysis of bisulfite-treated genomic DNA demonstrated a stretch of CpG demethylation within a nonpromoter CpG island of the aromatase gene in endometriotic cells. In endometrial cells, the CpG sequences were heavily methylated and associated with methyl-CpG-binding proteins. CONCLUSION(S): The up-regulation of the aromatase gene in endometriosis may be ascribed to the epigenetic disorder associated with aberrant DNA demethylation in a nonpromoter CpG island.


Asunto(s)
Aromatasa/genética , Islas de CpG/fisiología , Metilación de ADN/fisiología , Endometriosis/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Aromatasa/metabolismo , Endometriosis/metabolismo , Endometriosis/patología , Epigénesis Genética/fisiología , Femenino , Humanos , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Células del Estroma/enzimología , Células del Estroma/patología , Regulación hacia Arriba/fisiología , Útero/enzimología , Útero/patología
11.
Fertil Steril ; 93(1): 325-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19647233
12.
Glia ; 53(1): 67-73, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16158419

RESUMEN

Little is known about the effect of microglial activation on cell death. This study examines the effects of lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma), triggers of microglial activation, on cell death induced by several agents in cultured rat microglia. For comparison, the effect of LPS on cell death is also examined in cultured astrocytes. LPS or IFN-gamma enhanced cell death induced by thapsigargin or ionomycin, an agent that increases intracellular Ca2+ concentration, although LPS or IFN-gamma alone did not affect cell viability. Thapsigargin or ionomycin induced apoptosis in LPS-untreated microglia, while they induced necrosis in LPS-treated microglia, which were partially reversed by O,O'-bis(2-aminophenyl)ethyleneglycol-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester (BAPTA-AM, an intracellular Ca2+ chelator). In contrast, LPS treatment did not affect tunicamycin- or staurosporine-induced apoptosis, while it inhibited S-nitroso-N-acetylpenicillamine-induced apoptosis. The effect of LPS on thapsigargin or ionomycin-induced apoptosis was not observed in astrocytes. These results indicate that microglial activation sensitizes the cells toward cell death induced by the change in intracellular Ca2+ concentration and shifts the mode of cell death from apoptosis to necrosis.


Asunto(s)
Apoptosis/fisiología , Señalización del Calcio/fisiología , Calcio/metabolismo , Encefalitis/metabolismo , Gliosis/metabolismo , Microglía/metabolismo , Necrosis/metabolismo , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Calcio/farmacología , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Interacciones Farmacológicas/fisiología , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Encefalitis/fisiopatología , Gliosis/fisiopatología , Mediadores de Inflamación/farmacología , Interferón gamma/farmacología , Líquido Intracelular/efectos de los fármacos , Líquido Intracelular/metabolismo , Ionomicina/farmacología , Lipopolisacáridos/farmacología , Microglía/efectos de los fármacos , Necrosis/fisiopatología , Ratas , Ratas Wistar , S-Nitroso-N-Acetilpenicilamina/antagonistas & inhibidores , Tapsigargina/farmacología
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