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1.
Nat Aging ; 3(2): 162-172, 2023 02.
Article in English | MEDLINE | ID: mdl-37118113

ABSTRACT

Diminished insulin and insulin-like growth factor-1 signaling extends the lifespan of invertebrates1-4; however, whether it is a feasible longevity target in mammals is less clear5-12. Clinically utilized therapeutics that target this pathway, such as small-molecule inhibitors of phosphoinositide 3-kinase p110α (PI3Ki), provide a translatable approach to studying the impact of these pathways on aging. Here, we provide evidence that dietary supplementation with the PI3Ki alpelisib from middle age extends the median and maximal lifespan of mice, an effect that was more pronounced in females. While long-term PI3Ki treatment was well tolerated and led to greater strength and balance, negative impacts on common human aging markers, including reductions in bone mass and mild hyperglycemia, were also evident. These results suggest that while pharmacological suppression of insulin receptor (IR)/insulin-like growth factor receptor (IGFR) targets could represent a promising approach to delaying some aspects of aging, caution should be taken in translation to humans.


Subject(s)
Longevity , Phosphatidylinositol 3-Kinases , Mice , Animals , Male , Humans , Female , Aging , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Mammals/metabolism , Dietary Supplements
2.
Redox Biol ; 53: 102341, 2022 07.
Article in English | MEDLINE | ID: mdl-35623315

ABSTRACT

The role of mitochondrial ROS in signalling muscle adaptations to exercise training has not been explored in detail. We investigated the effect of supplementation with the mitochondria-targeted antioxidant MitoQ on a) the skeletal muscle mitochondrial and antioxidant gene transcriptional response to acute high-intensity exercise and b) skeletal muscle mitochondrial content and function following exercise training. In a randomised, double-blind, placebo-controlled, parallel design study, 23 untrained men (age: 44 ± 7 years, VO2peak: 39.6 ± 7.9 ml/kg/min) were randomised to receive either MitoQ (20 mg/d) or a placebo for 10 days before completing a bout of high-intensity interval exercise (cycle ergometer, 10 × 60 s at VO2peak workload with 75 s rest). Blood samples and vastus lateralis muscle biopsies were collected before exercise and immediately and 3 h after exercise. Participants then completed high-intensity interval training (HIIT; 3 sessions per week for 3 weeks) and another blood sample and muscle biopsy were collected. There was no effect of acute exercise or MitoQ on systemic (plasma protein carbonyls and reduced glutathione) or skeletal muscle (mtDNA damage and 4-HNE) oxidative stress biomarkers. Acute exercise-induced increases in skeletal muscle peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1-α) mRNA expression were augmented in the MitoQ group. Despite this, training-induced increases in skeletal muscle mitochondrial content were similar between groups. HIIT-induced increases in VO2peak and 20 km time trial performance were also similar between groups while training-induced increases in peak power achieved during the VO2peak test were augmented in the MitoQ group. These data suggest that training-induced increases in peak power are enhanced following MitoQ supplementation, which may be related to the augmentation of skeletal muscle PGC1α expression following acute exercise. However, these effects do not appear to be related to an effect of MitoQ supplementation on exercise-induced oxidative stress or training-induced mitochondrial biogenesis in skeletal muscle.


Subject(s)
Antioxidants , Exercise , Organophosphorus Compounds/pharmacology , Ubiquinone/analogs & derivatives , Adult , Antioxidants/metabolism , Dietary Supplements , Exercise/physiology , Humans , Male , Middle Aged , Mitochondria/metabolism , Muscle, Skeletal/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Ubiquinone/pharmacology
3.
Appl Physiol Nutr Metab ; 47(7): 762-774, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35201920

ABSTRACT

Unaccustomed exercise causes muscle damage resulting in loss of muscle function, which may be attributable to exercise-induced increases in skeletal muscle reactive oxygen species. This study examined the effect of mitochondria-targeted antioxidant supplementation on recovery of muscle function following exercise. Thirty-two untrained men received MitoQ (20 mg/day) or a placebo for 14 days before performing  300 maximal eccentric contractions of the knee extensor muscles of 1 leg. Muscle function was assessed using isokinetic dynamometry before, immediately after, and 24, 48, 72, and 168 hours after exercise. Muscle soreness was assessed using a visual analogue scale 24, 48, 72, and 168 hours after exercise. Blood samples were collected before, immediately after, and 2, 24, 48, 72, and 168 hours after exercise and urine samples were collected before and during the 48 hours after exercise. The reduction in maximal voluntary isometric contraction force and peak concentric torque following exercise was unaffected by MitoQ while recovery of peak eccentric torque was delayed in the MitoQ group. Exercise-induced increases in urine F2-isoprostanes were unaffected by MitoQ. MitoQ augmented exercise-induced increases in plasma creatine kinase levels, while plasma IL-6 was similar between groups. Muscle soreness was not affected by MitoQ. These results indicate that MitoQ does not attenuate post-exercise muscle soreness and may delay recovery of muscle function following eccentric exercise. Trial registration number: ACTRN12620001089921. Novelty: Post-exercise recovery of maximal voluntary isometric contraction force and peak concentric torque were unaffected by MitoQ. MitoQ delayed post-exercise recovery of peak eccentric torque. Post-exercise muscle soreness was unaffected by MitoQ.


Subject(s)
Isometric Contraction , Muscular Diseases , Antioxidants/pharmacology , Creatine Kinase , Dietary Supplements , F2-Isoprostanes , Humans , Male , Mitochondria , Muscle Contraction/physiology , Muscle, Skeletal/physiology , Myalgia/prevention & control , Torque
4.
J Food Allergy ; 4(3): 163-171, 2022 Dec.
Article in English | MEDLINE | ID: mdl-39036772

ABSTRACT

Background: Approximately 6 million children in the United States have a diagnosed food allergy, and 32% of caregivers experience significant psychological distress due to the diagnosis. Despite substantial impacts on psychosocial health and quality of life, few interventions aim to help caregivers of newly diagnosed children. There is a clear, unmet need for interventions to address caregiver distress, especially after the initial diagnosis. Objective: We developed a mobile psychosocial health intervention, the Food Allergy Symptom Self-Management with Technology (FASST) app. Primary end points were to determine the app's feasibility and caregiver satisfaction. Methods: This was a phase II, randomized controlled, implementation study (4-week duration) in caregivers (N = 30) of children ≤ 18 years of age who were newly diagnosed with a food allergy (≤90 days after the diagnosis). Caregivers (n = 20) were randomized to use the FASST app (intervention group) with access to individualized, self-help symptom relief interventions and food allergy support, and educational resources; or to use a limited app with a basic FASST interface and links to a few educational resources (control group [n = 10]). Ten participants (intervention group, n = 5; control group, n = 5) participated in semistructured interviews at week 4. Results: Both groups found the app relatively easy to use. The intervention group scores for safety preparedness during social activities increased by 24%, whereas those in the control group experienced a 1% decline. The intervention group participants increased the use of websites to find food allergy information by 17% at week 4 compared with 4% for the control group. Although the intervention group participants showed greater gains than did those in the control group in their confidence to prepare for and prevent allergic reactions, and greater declines in perceived social limitations, more participants in the control group endorsed confidence in their ability to recognize (11% versus 5%, respectively) and treat (10% versus 6%, respectively) allergic reactions. Conclusion: Analysis of our results suggests that the FASST app may provide a feasible means of delivering psychosocial and educational supports to caregivers of children recently diagnosed with a food allergy.Clinical trial NCT04512924, www.clinicaltrials.gov.

5.
J Int Soc Sports Nutr ; 18(1): 58, 2021 Aug 21.
Article in English | MEDLINE | ID: mdl-34419082

ABSTRACT

BACKGROUND: Exercise increases skeletal muscle reactive oxygen species (ROS) production, which may contribute to the onset of muscular fatigue and impair athletic performance. Mitochondria-targeted antioxidants such as MitoQ, which contains a ubiquinone moiety and is targeted to mitochondria through the addition of a lipophilic triphenylphosphonium cation, are becoming popular amongst active individuals as they are designed to accumulate within mitochondria and may provide targeted protection against exercise-induced oxidative stress. However, the effect of MitoQ supplementation on cycling performance is currently unknown. Here, we investigate whether MitoQ supplementation can improve cycling performance measured as time to complete an 8 km time trial. METHOD: In a randomized, double-blind, placebo-controlled crossover study, 19 middle-aged (age: 44 ± 4 years) recreationally trained (VO2peak: 58.5 ± 6.2 ml·kg- 1·min- 1, distance cycled per week during 6 months prior to study enrollment: 158.3 ± 58.4 km) male cyclists completed 45 min cycling at 70% VO2peak followed by an 8 km time trial after 28 days of supplementation with MitoQ (20 mg·day- 1) and a placebo. Free F2-isoprostanes were measured in plasma samples collected at rest, after 45 min cycling at 70% VO2peak and after completion of the time trial. Respiratory gases and measures of rating of perceived exertion (RPE) were also collected. RESULTS: Mean completion time for the time trial was 1.3% faster with MitoQ (12.91 ± 0.94 min) compared to placebo (13.09 ± 0.95 min, p = 0.04, 95% CI [0.05, 2.64], d = 0.2). There was no difference in RPE during the time trial between conditions (p = 0.82) despite there being a 4.4% increase in average power output during the time trial following MitoQ supplementation compared to placebo (placebo; 270 ± 51 W, MitoQ; 280 ± 53 W, p = 0.04, 95% CI [0.49, 8.22], d = 0.2). Plasma F2-isoprostanes were lower on completion of the time trial following MitoQ supplementation (35.89 ± 13.6 pg·ml- 1) compared to placebo (44.7 ± 16.9 pg·ml- 1 p = 0.03). CONCLUSION: These data suggest that MitoQ supplementation may be an effective nutritional strategy to attenuate exercise-induced increases in oxidative damage to lipids and improve cycling performance.


Subject(s)
Antioxidants/pharmacology , Athletic Performance/physiology , Bicycling/physiology , Mitochondria, Muscle/drug effects , Organophosphorus Compounds/pharmacology , Performance-Enhancing Substances/pharmacology , Ubiquinone/analogs & derivatives , Adult , Antioxidants/metabolism , Cross-Over Studies , Double-Blind Method , F2-Isoprostanes/blood , Humans , Lipid Peroxidation , Male , Middle Aged , Mitochondria, Muscle/metabolism , Muscle, Skeletal/metabolism , Organophosphorus Compounds/metabolism , Oxidative Stress/drug effects , Oxygen Consumption , Performance-Enhancing Substances/metabolism , Physical Exertion/drug effects , Physical Exertion/physiology , Placebos/metabolism , Placebos/pharmacology , Reactive Oxygen Species/metabolism , Sports Nutritional Physiological Phenomena/drug effects , Sports Nutritional Physiological Phenomena/physiology , Time Factors , Ubiquinone/metabolism , Ubiquinone/pharmacology
7.
Sci Rep ; 10(1): 17785, 2020 10 20.
Article in English | MEDLINE | ID: mdl-33082367

ABSTRACT

For centuries humans have been fascinated by the natural beauty of horses in motion and their different gaits. Gait classification (GC) is commonly performed through visual assessment and reliable, automated methods for real-time objective GC in horses are warranted. In this study, we used a full body network of wireless, high sampling-rate sensors combined with machine learning to fully automatically classify gait. Using data from 120 horses of four different domestic breeds, equipped with seven motion sensors, we included 7576 strides from eight different gaits. GC was trained using several machine-learning approaches, both from feature-extracted data and from raw sensor data. Our best GC model achieved 97% accuracy. Our technique facilitated accurate, GC that enables in-depth biomechanical studies and allows for highly accurate phenotyping of gait for genetic research and breeding. Our approach lends itself for potential use in other quadrupedal species without the need for developing gait/animal specific algorithms.


Subject(s)
Automation/methods , Computer Simulation , Gait , Horses , Image Processing, Computer-Assisted/methods , Lameness, Animal/diagnosis , Machine Learning , Algorithms , Animals , Biomechanical Phenomena , Motion , Phenotype
9.
J Environ Qual ; 43(2): 723-31, 2014 Mar.
Article in English | MEDLINE | ID: mdl-25602673

ABSTRACT

Previous work has estimated the hydroperiod requirements (saturation duration and frequency) of wetland plant communities by modeling their hydrologic regimes in natural (never drained) wetlands for a 40-yr period. This study tested the modeled predictions in a controlled greenhouse study using tree species representing three of the plant communities plus an additional species from another community. Bald cypress ( L. Rich.), sweet bay ( L.), pond pine ( Michx.), and swamp chestnut oak ( Nutt.) were grown under three hydroperiods (continuously ponded for 100 d, intermittently ponded for 14 d, and unsaturated) in loamy sand and sapric (organic) materials. Bald cypress (representing a Nonriverine Swamp Forest community) adapted well to 100 d of ponding by producing lateral roots near the soil surface and aerenchyma tissue in roots and stem. Sweet bay (Bay Forest community) also adapted well to 100 d of ponding by producing adventitious roots on the submerged portion of the stem. Pond pine (Pond Pine Woodland) and swamp chestnut oak (Nonriverine Wet Hardwood Forest) were intolerant of 100 d of ponded conditions. Seventy-five percent of the pond pine seedlings and 87% of the swamp chestnut oak seedlings died in the continuously ponded treatment level, whereas 100% of the bald cypress and 88% of the sweet bay seedlings survived. Results from this study suggest that modeled long-term hydroperiods of natural wetland plant communities can be used for restoration of these communities.

10.
Anaesth Intensive Care ; 35(1): 94-8, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17323674

ABSTRACT

Omphalocele is one of the most common fetal abdominal wall defects. When this defect is of giant size, significant respiratory compromise may occur and impact on prognosis. We present three infants with giant omphalocele, highlighting the potential need for ongoing ventilatory support after the neonatal period in children born with this condition. The three cases had very different outcomes but all had significant ventilatory insufficiency and required substantial respiratory support at least into the second year of life. The possibility of a requirement for long-term ventilatory support should be discussed with families at antenatal diagnosis. A conservative surgical approach, together with early monitoring for hypoventilation and screening for the development of pulmonary hypertension is indicated for these children to limit morbidity. We suggest early tertiary respiratory input and advocate for a specific case manager to oversee the regional care of these children.


Subject(s)
Hernia, Umbilical/complications , Positive-Pressure Respiration , Respiratory Insufficiency/therapy , Female , Hernia, Umbilical/diagnostic imaging , Humans , Infant , Infant, Low Birth Weight , Infant, Newborn , Male , Prognosis , Radiography , Respiratory Insufficiency/etiology
11.
Pediatr Pulmonol ; 39(3): 238-46, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15635620

ABSTRACT

New Zealand children's morbidity from respiratory disease is high. This study examines whether subclinical ciliary abnormalities underlie the increased prevalence of respiratory disease in indigenous New Zealand children. A prospective study enrolled a group of healthy children who were screened for respiratory disease by questionnaire and lung function. Skin-prick tests were performed to control for atopy. Exhaled and nasal NO was measured online by a single-breath technique using chemiluminescence. Ciliary specimens were obtained by nasal brushings for assessment of structure and function. The ciliary beat frequency (CBF) (median CBF, 12.5 Hz; range, 10.4-16.8 Hz) and NO values (median exhaled NO, 5.6 ppb; range, 2.3-87.7 ppb; median nasal NO, 403 ppb; range, 34-1,120 ppb) for healthy New Zealand European (n=58), Pacific Island (n=61), and Maori (n=16) children were comparable with levels reported internationally. No ethnic differences in NO, atopy, or CBF were demonstrated. Despite an apparently normal ciliary beat, the percentage of ciliary structural defects was 3 times higher than reported controls (9%; range, 3.6-31.3%), with no difference across ethnic groups. In conclusion, it is unlikely that subclinical ciliary abnormalities underlie the increased prevalence of respiratory disease in indigenous New Zealand children. The high percentage of secondary ciliary defects suggests ongoing environmental or infective damage.


Subject(s)
Mucociliary Clearance/physiology , Nitric Oxide/metabolism , Population Groups/statistics & numerical data , Respiratory Tract Diseases/ethnology , Respiratory Tract Diseases/physiopathology , Adolescent , Asthma/ethnology , Asthma/physiopathology , Breath Tests , Bronchitis/ethnology , Bronchitis/physiopathology , Child , Child, Preschool , Cilia/pathology , Cilia/physiology , Europe/ethnology , Genetic Predisposition to Disease/epidemiology , Humans , Nasal Mucosa/physiology , Nasal Mucosa/physiopathology , Native Hawaiian or Other Pacific Islander/statistics & numerical data , New Zealand/epidemiology , Prospective Studies , Reference Values , Respiratory Function Tests , Respiratory Hypersensitivity/ethnology , Respiratory Hypersensitivity/physiopathology , Respiratory Tract Diseases/diagnosis , Respiratory Tract Diseases/genetics , Skin Tests , White People/statistics & numerical data
12.
Vaccine ; 17(22): 2826-9, 1999 Jul 16.
Article in English | MEDLINE | ID: mdl-10438052

ABSTRACT

This study was designed to determine the safety and immunogenicity in volunteers of a DNA vaccine consisting of a plasmid encoding hepatitis B surface antigen delivered by the PowderJect XR1 gene delivery system into human skin. Seven healthy adult volunteers received two immunizations at one of three forces of delivery on day 0 and 56. The vaccine was well tolerated. One of six seronegative volunteers developed high titers of persistent HBsAb after a single immunization. In retrospect, this volunteer may have had previous exposure to hepatitis B. Our study suggests that the hepatitis B DNA vaccine given by this gene delivery system may induce a booster response, but the vaccine at the extremely low DNA dose used (0.25 microg) did not induce primary immune responses.


Subject(s)
Hepatitis B Surface Antigens/genetics , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines/therapeutic use , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Hepatitis B/immunology , Hepatitis B/prevention & control , Vaccines, DNA/therapeutic use , Adolescent , Adult , Antibodies, Viral/blood , DNA, Viral/adverse effects , DNA, Viral/therapeutic use , Drug Delivery Systems/adverse effects , Hepatitis B Vaccines/adverse effects , Humans , Immunity, Mucosal/immunology , Injections, Intradermal/adverse effects , Middle Aged , Vaccines, DNA/adverse effects
13.
Br J Theatre Nurs ; 5(8): 30, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8695953
18.
Biotechniques ; 8(4): 370-1, 1990 Apr.
Article in English | MEDLINE | ID: mdl-1692715

ABSTRACT

We describe a simplified Northern blot hybridization procedure. This procedure eliminates the need for many reagents commonly used in RNA hybridization and replaces them with two buffers containing 5% sodium dodecyl sulfate for pre-hybridization, hybridization and all post-hybridization washes.


Subject(s)
Sodium Dodecyl Sulfate , Animals , Blotting, Northern/methods , DNA Probes , Mice , Nucleic Acid Hybridization , RNA/analysis
19.
Development ; 104(1): 137-45, 1988 Sep.
Article in English | MEDLINE | ID: mdl-3075542

ABSTRACT

Homologous serum, when repeatedly used for the culture of postimplantation rat embryos, rapidly loses its capacity to support growth and development. Replenishment of the 'exhausted' serum with glucose and vitamins (MEM vitamin concentrate--Flow Laboratories) together with gentle dialysis to remove small molecular weight toxic metabolites (lactate etc) fails to restore the growth-promoting properties of the serum. This suggests that 'recycled' serum has been depleted of specific growth-promoting factors. Such serum that has been subjected to dialysis can be completely replenished by addition of 30% normal rat serum. It is therefore probable that the growth promoters are originally present at very low concentrations and become rate limiting when serum is recycled. Many growth factors and hormones fall into this category and it is likely that a considerable number are involved when serum is 'exhausted' by repeated use. When insulin, epidermal growth factor or rat transferrin are added to dialysed 'exhausted' serum each effects a partial restoration of growth of rat embryos.


Subject(s)
Culture Media , Embryo, Mammalian/physiology , Epidermal Growth Factor/pharmacology , Insulin/pharmacology , Transferrin/pharmacology , Animals , Blood , Cells, Cultured , Female , Pregnancy , Rats , Rats, Inbred Strains
20.
Cell ; 40(3): 537-46, 1985 Mar.
Article in English | MEDLINE | ID: mdl-2982497

ABSTRACT

Rous sarcoma virus expresses a transcriptional activator that affects the LTR as well as other promoters. We discern this activity as a stimulation of the transient expression of an LTR-promoted hybrid transcriptional unit and also of the rat preproinsulin II gene in transfected NIH 3T3 cells. We map the activity to an alternate reading frame in the p19-p10 region of the gag gene and identify a mRNA whose spliced structure would direct translation of this reading frame from the Pr76gag initiation codon. This mRNA probably differs from genomic RNA only by the 282 nucleotide splice. The predicted translation product is a 124 residue polypeptide; the first six amino acids arise from gag. The target for the action of this transcriptional modulator at the LTR lies between 111 and 620 nucleotides upstream of the cap site.


Subject(s)
Avian Sarcoma Viruses/genetics , Transcription Factors/genetics , Animals , Base Sequence , Cell Line , Cloning, Molecular , Genes, Viral , Insulin , Mice , Nucleic Acid Hybridization , Plasmids , Proinsulin/genetics , Promoter Regions, Genetic , Protein Biosynthesis , Protein Precursors/genetics , RNA, Messenger/genetics , RNA, Viral/genetics , Rats , Repetitive Sequences, Nucleic Acid , Transcription, Genetic , Transfection
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