A5014318990- Muscle metabolism and nutrition
- Nutrition and Health in Aging
- Muscle Physiology and Disorders
- Diet and metabolism studies
- Adipose Tissue and Metabolism
- Exercise and Physiological Responses
- Sports Performance and Training
- Genetics and Physical Performance
- Cardiovascular and exercise physiology
- Metabolism, Diabetes, and Cancer
- Frailty in Older Adults
- Metabolism and Genetic Disorders
- Body Composition Measurement Techniques
- Clinical Nutrition and Gastroenterology
- Metabolomics and Mass Spectrometry Studies
- Liver Disease Diagnosis and Treatment
- Nutritional Studies and Diet
- Balance, Gait, and Falls Prevention
- Mitochondrial Function and Pathology
- Alcohol Consumption and Health Effects
- Obesity, Physical Activity, Diet
- Mosquito-borne diseases and control
- MicroRNA in disease regulation
- Diabetes Management and Research
- Physical Activity and Health
The University of Texas at San Antonio
2024-2025
The University of Texas Medical Branch at Galveston
2015-2024
The University of Texas Health Science Center at San Antonio
2024
The University of Texas Health Science Center at Houston
2024
Icahn School of Medicine at Mount Sinai
2024
John Sealy Hospital
2009-2023
Azienda Ospedaliera Universitaria Pisana
2022
Galveston College
2000-2019
Texas Medical Board
2019
Texas Woman's University
2016
Brown adipose tissue (BAT) has attracted scientific interest as an antidiabetic owing to its ability dissipate energy heat. Despite a plethora of data concerning the role BAT in glucose metabolism rodents, (if any) humans remains unclear. To investigate whether activation alters whole-body homeostasis and insulin sensitivity humans, we studied seven BAT-positive (BAT+) men five BAT-negative (BAT−) under thermoneutral conditions after prolonged (5–8 h) cold exposure (CE). The two groups were...
Resistance exercise is a potent stimulator of muscle protein synthesis and cell growth, with the increase in being detected within 2-3 h post-exercise remaining elevated for up to 48 h. However, during exercise, inhibited. An AMP-activated kinase (AMPK) activity has recently been shown decrease mammalian target rapamycin (mTOR) signalling key regulators translation initiation. We hypothesized that cellular mechanism inhibition an acute bout resistance humans would be associated activation...
Low-intensity resistance exercise training combined with blood flow restriction (REFR) increases muscle size and strength as much conventional high loads. However, the cellular mechanism(s) underlying hypertrophy gains induced by REFR are unknown. We have recently shown that both mammalian target of rapamycin (mTOR) signaling pathway protein synthesis (MPS) were stimulated after an acute bout high-intensity in humans. Therefore, we hypothesized would enhance mTOR stimulate MPS. measured MPS...
We recently demonstrated that muscle protein synthesis was stimulated to a similar extent in young and elderly subjects during 3-h amino acid infusion. sought determine if more practical bolus oral ingestion would also produce response (34 ± 4 yr) (67 2 individuals. Arteriovenous blood samples biopsies were obtained primed (2.0 μmol/kg) constant infusion (0.05 μmol·kg -1 ·min ) of l-[ ring- H 5 ]phenylalanine. Muscle kinetics mixed fractional synthetic rate (FSR) calculated before after the...
Muscle mass declines with aging. Amino acids alone stimulate muscle protein synthesis in the elderly. However, mixed nutritional supplementation failed to improve mass. We hypothesized that failure of supplements is due altered responsiveness anabolism increased amino acid availability associated endogenous hyperinsulinemia. measured and breakdown, transport healthy young (30 +/- 3 yr) elderly (72 1 volunteers basal postabsorptive state during administration an acid-glucose mixture, using...
We recently showed that resistance exercise and ingestion of essential amino acids with carbohydrate (EAA+CHO) can independently stimulate mammalian target rapamycin (mTOR) signaling muscle protein synthesis in humans. Providing an EAA+CHO solution postexercise further increase synthesis. Therefore, we hypothesized enhanced mTOR might be responsible for the greater when leucine-enriched EAA+CHOs are ingested during recovery. Sixteen male subjects were randomized to one two groups (control or...
Muscle protein synthesis and mTORC1 signalling are concurrently stimulated following muscle contraction in humans. In an effort to determine whether is essential for regulating humans, we treated subjects with a potent inhibitor (rapamycin) prior performing series of high-intensity contractions. Here show that rapamycin treatment blocks the early (1-2 h) acute contraction-induced increase ( approximately 40%) human synthesis. addition, several downstream components pathway were also blunted...
Muscle protein synthesis and breakdown amino acid transport were measured in 7 healthy young (30 ± 2 yr) 8 elderly (71 volunteers the postabsorptive state during oral administration of an mixture withl-[ ring- H 5 ]phenylalanine infusion, femoral artery vein catheterization, muscle biopsies. Phenylalanine first-pass splanchnic extraction was by addingl-[ 13 C 6 to mixture. In state, no differences kinetics detected between volunteers. significantly higher ( P < 0.003) ingestion acids, but...
ContextSarcopenia is associated with loss of strength and function, eventually leading to independence. Some studies suggest that basal muscle protein turnover reduced aging, but other do not confirm this finding.ObjectiveTo determine if aging per se affects in men.Design SettingCross-sectional study conducted from June 1997 July 2000 a general US community.ParticipantsTwenty-six young (mean [SE] age, 28 [2] years) 22 older 70 [1] men, who were healthy independent based on activities daily...
We have investigated the response of amino acid transport and protein synthesis in healthy elderly individuals (age 71+/-2 yr) to stimulatory effect increased availability. Muscle breakdown, were measured postabsorptive state during intravenous infusion an mixture. Muscle-free kinetics calculated by means a three compartment model using data obtained femoral arterio-venous catheterization muscle biopsies from vastus lateralis stable isotope tracers acids. In addition, fractional synthetic...
A reduced response of older skeletal muscle to anabolic stimuli may contribute the development sarcopenia. We hypothesized that proteins are resistant action insulin in elderly. examined effects hyperinsulinemia on protein metabolism young (25+/-2 year) and (68+/-1 healthy subjects using stable isotope tracer techniques. Leg blood flow was higher at baseline increased during hyperinsulinemia, whereas it did not change Glucose concentrations uptake were different between groups...
Skeletal muscle loss during aging leads to an increased risk of falls, fractures, and eventually independence. Resistance exercise is a useful intervention prevent sarcopenia; however, the protein synthesis (MPS) response resistance less in elderly compared with young subjects. On other hand, essential amino acids (EAA) increase MPS equally both old subjects when sufficient EAA ingested. We hypothesized that ingestion following bout would stimulate anabolic signaling similarly between men....
The loss of skeletal muscle mass during aging, sarcopenia, increases the risk for falls and dependence. Resistance exercise (RE) is an effective rehabilitation technique that can improve strength; however, older individuals are resistant to stimulation protein synthesis (MPS) with traditional high-intensity RE. Recently, a novel method, low-intensity RE, combined blood flow restriction (BFR), has been shown stimulate mammalian target rapamycin complex 1 (mTORC1) signaling MPS in young men....
Abstract Background Sarcopenia, the loss of skeletal muscle mass during aging, increases risk for falls and dependency. Resistance exercise (RE) training is an effective treatment to improve strength in older adults, but aging associated with a smaller amount training-induced hypertrophy. This may be due part inability stimulate muscle-protein synthesis (MPS) after acute bout RE. We hypothesized that adults would have impaired mammalian target rapamycin complex (mTORC)1 signaling MPS...
The mammalian target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK) are important nutrient- energy-sensing signalling proteins in skeletal muscle. AMPK activation decreases muscle synthesis by inhibiting mTOR to regulatory associated with translation initiation elongation. On the other hand, essential amino acids (leucine particular) insulin stimulate synthesis. We hypothesized that anabolic nutrients would be sensed both mTOR, resulting an acute potent stimulation human via...
Key points Five days of bed rest resulted in a reduction leg lean mass and strength older adults. After rest, (but not younger) adults had reduced amino acid‐induced anabolic sensitivity (blunted muscle protein synthesis; MPS) enhanced markers associated with the ubiquitin proteasome autophagy–lysosomal systems (increase molecular related to proteolysis). Younger did lose (via DXA) after 5 despite blunted mTORC1 signalling increased skeletal REDD1, REDD2 MURF1 mRNA expression. Exercise...