| 1. |
- Montiel Rojas, Diego, 1984-, et al.
(author)
-
Short Telomere Length Is Related to Limitations in Physical Function in Elderly European Adults
- 2018
-
In: Frontiers in Physiology. - : Frontiers Media S.A.. - 1664-042X. ; 9
-
Journal article (peer-reviewed)abstract
- The present study aims to explore the potential influence of leucocyte telomere length (LTL) on both a single indicator and a composite construct of physical functioning in a large European population of elderly men and women across diverse geographical locations. A total of 1,221 adults (65-79 years) were recruited from five European countries within the framework of NU-AGE study. The physical functioning construct was based on the 36-item Short Form Health Survey. Handgrip strength was used as a single indicator of muscle function and LTL was assessed using quantitative real-time PCR. Women had significantly longer (p < 0.05) LTL than men. Participants in Poland had significantly shorter LTL than in the other study centers, whereas participants in the Netherlands had significantly longer LTL than most of the other centers (p < 0.01). An analysis of LTL as a continuous outcome against physical functioning by using linear models revealed inconsistent findings. In contrast, based on an analysis of contrasting telomere lengths (first vs. fifth quintile of LTL), a significant odds ratio (OR) of 1.7 (95% CI: 1.1 -2.6; p < 0.05) of having functional limitation was observed in those belonging to the first LTL quintile compared to the fifth. Interestingly, having the shortest LTL was still related to a higher likelihood of having physical limitation when compared to all remaining quintiles (OR: 1.5, 95% CI: 1.1 -2.1; p < 0.05), even after adjustment by study center, age, sex, and overweight status. Collectively, our findings suggest that short LTL is an independent risk factor that accounts for functional decline in elderly European populations. The influence of LTL on functional limitation seems driven by the detrimental effect of having short telomeres rather than reflecting a linear dose-response relationship.
|
|
| 2. |
- Montiel Rojas, Diego, 1984-
(author)
-
Diet and sarcopenia risk in community-dwelling older European adults
- 2022
-
Doctoral thesis (other academic/artistic)abstract
- The age-related decline in muscle strength and muscle mass can lead to sarcopenia with higher risk of falls, disability, and loss of independence. In this context, healthy dietary habits have the potential to delay onset of physical limitations, thereby promoting healthy ageing. The overall aim of the thesis was to investigate the role of dietary habits on indicators ofmuscle health in a sample of community-dwelling older European men and women. The studies were performed within the frame of the NU-AGE project, a multi-centre study aiming to determine the impact of dietary habits on age-related functional decline. Studies I-III were based on crosssectional analyses, whereas study IV was a randomised controlled trial (RCT). In summary, Study I highlighted the independent roles of dietary protein amount and quality for muscle health in older adults. A positive linear dose-response relationship existed between protein intake and muscle health, with increased intake of plant-based proteins to the detriment of animal-based proteins was associated with reduced sarcopenia risk. Study II revealed that increased poly-unsaturated fatty acids intake to the detriment of saturated fatty acids was associated with lower sarcopenia risk in older adults with a dietary protein intake below 1.1 g/kg of body weight. In Study III, beneficial links between dietary fibre intake and muscle mass were observed in older European adults. In Study IV, a one-year RCT promoting adherence to a Mediterranean-style diet did not result in significant changes in muscle strength or mass. In conclusion, the present dissertation emphasised the important potential of macronutrient amount and quality in the prevention of age-related loss of muscle strength and muscle mass. However, future experimental studies are warranted to clarify the impact of whole-diet approaches, such as the Mediterranean diet, on the maintenance of muscle health in older adults.
|
|
| 3. |
- Strandberg, Emelie, 1986-, et al.
(author)
-
Influence of combined resistance training and healthy diet on muscle mass in healthy elderly women : a randomized controlled trial
- 2015
-
In: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 119:8, s. 918-925
-
Journal article (peer-reviewed)abstract
- The delivery of efficient nonpharmacological treatment to prevent the loss of muscle mass in older adults is a major challenge, and information on the combined effects of training and diet is particularly important. Here we aimed to evaluate the effects of 24 wk of resistance training combined with a healthy dietary approach (n-6/n-3 ratio < 2) in a population of healthy and physically active older women (65-70 years). The three-armed randomized controlled trial included a resistance training + healthy diet group (RT-HD), a resistance training group (RT), and controls (CON). All subjects included in the study were physically active and had low levels of serum inflammatory markers. In accordance with the dietary goals, the n-6/n-3 ratio dietary intake significantly decreased only in RT-HD by 42%. An increase in 1 repetition maximum in leg extension occurred in RT (+20.4%) and RT-HD (+20.8%), but not in CON. Interestingly, leg lean mass significantly increased only in RT-HD (+1.8%). While there were no changes in serum C-reactive protein and IL-6 levels, a significant decrease in serum level of the pro-inflammatory precursor arachidonic acid (-5.3 +/- 9.4%) together with an increase in serum n-3 docosahexaenoic acid (+8.3%) occurred only in RT-HD. Altogether, this study demonstrates that the effects of resistance training on muscle mass in healthy older adults can be optimized by the adoption of a healthy diet.
|
|
| 4. |
- Bankole, Landry-Cyrille, 1970-, et al.
(author)
-
Fibre type-specific satellite cell content in two models of muscle disease
- 2013
-
In: Histopathology. - : Wiley. - 0309-0167 .- 1365-2559. ; 63:6, s. 826-832
-
Journal article (peer-reviewed)abstract
- Aims: Muscle satellite cells (SCs) are responsible for the regenerative events following muscle fibre injury. This study aimed to improve our understanding of SC behaviour in two models of muscle disorder with different pathological mechanisms and onset of disease.Methods and results: Pax7(+)SC content was assessed in types I and II fibres of patients with Duchenne muscular dystrophy (DMD; n=9; age 132years), polymyositis/dermatomyositis (PM/DM; n=9; age 52 +/- 12years) and in controls (n=5; age 26 +/- 5years). Pax7(+)SCs number in type I and II fibres was higher (P<0.05) in DMD and in PM/DM compared to controls. Type I fibres were associated with a higher number of Pax7(+)SCs compared to type II fibres only in DMD; Pax7(+)SCs number in type I fibres was about threefold higher in DMD compared to PM/DM (P<0.05). In DMD, Pax7(+)SC content in small regenerating fibres (0.09 +/- 0.09 SCs/fibre) was similar to that in fibres from healthy skeletal muscle. The proportion of activated SCs (Ki-67(+)SCs) was fivefold lower in DMD (0.4 +/- 0.4%) compared to PM/DM (2.8 +/- 2%). Pax7(+) cells located outside the basal lamina were observed in DMD muscles only.Conclusion: The capacity to generate new SCs is increased even in severely impaired muscles and a fibre type-specific enhancement of SC occurs in type I muscle fibres in DMD.
|
|
| 5. |
- Bankole, Landry-Cyrille, 1977-, et al.
(author)
-
Safety and efficacy of a 6-month home-based exercise program in patients with facioscapulohumeral muscular dystrophy A randomized controlled trial
- 2016
-
In: Medicine. - : Lippincott Williams & Wilkins. - 0025-7974 .- 1536-5964. ; 95:31
-
Journal article (peer-reviewed)abstract
- Background: Previous randomized controlled trials investigating exercise training programs in facioscapulohumeral muscular dystrophy (FSHD) patients are scarce and of short duration only. This study assessed the safety and efficacy of a 6-month home-ased exercise training program on fitness, muscle, and motor function in FSHD patients.Methods: Sixteen FSHD patients were randomly assigned to training (TG) and control (CG) groups (both n=8) in a home-based exercise intervention. Training consisted of cycling 3 times weekly for 35minutes (combination of strength, high-intensity interval, and low-intensity aerobic) at home for 24 weeks. Patients in CG also performed an identical training program (CTG) after 24 weeks. The primary outcome was change in peak oxygen uptake (VO2 peak) measured every 6 weeks. The principal secondary outcomes were maximal quadriceps strength (MVC) and local quadriceps endurance every 12 weeks. Other outcome measures included maximal aerobic power (MAP) and experienced fatigue every 6 weeks, 6-minute walking distance every 12 weeks, and muscle characteristics from vastus lateralis biopsies taken pre- and postintervention.Results: The compliance rate was 91% in TG. Significant improvements with training were observed in the VO2 peak (+19%, P= 0.002) and MAP by week 6 and further to week 24. Muscle endurance, MVC, and 6-minute walking distance increased and experienced fatigue decreased. Muscle fiber cross-sectional area and citrate synthase activity increased by 34% (P=0.008) and 46% (P=0.003), respectively. Dystrophic pathophysiologic patterns were not exacerbated. Similar improvements were experienced by TG and CTG.Conclusions: A combined strength and interval cycling exercise-training program compatible with patients' daily professional and social activities leads to significant functional benefits without compromising muscle tissue.
|
|
| 6. |
- Daussin, Frederic, et al.
(author)
-
Effect of interval versus continuous training on cardiorespiratory and mitochondrial functions : relationship to aerobic performance improvements in sedentary subjects
- 2008
-
In: American Journal of Physiology. Regulatory Integrative and Comparative Physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 295:1, s. R264-272
-
Journal article (peer-reviewed)abstract
- The goal of the study was to determine the effects of continuous (CT) vs. intermittent (IT) training yielding identical mechanical work and training duration on skeletal muscle and cardiorespiratory adaptations in sedentary subjects. Eleven subjects (6 men and 5 women, 45 +/- 3 years) were randomly assigned to either of the two 8-wk training programs in a cross-over design, separated by 12 wk of detraining. Maximal oxygen uptake (Vo2max) increased after both trainings (9% with CT vs. 15% with IT), whereas only IT was associated with faster Vo2 kinetics (tau: 68.0 +/- 1.6 vs. 54.9 +/- 0.7 s, P < 0.05) measured during a test to exhaustion (TTE) and with improvements in maximal cardiac output (Qmax, from 18.1 +/- 1.1 to 20.1 +/- 1.2 l/min; P < 0.01). Skeletal muscle mitochondrial oxidative capacities (Vmax) were only increased after IT (3.3 +/- 0.4 before and 4.5 +/- 0.6 micromol O2 x min(-1) x g dw(-1) after training; P < 0.05), whereas capillary density increased after both trainings, with a two-fold higher enhancement after CT (+21 +/- 1% for IT and +40 +/- 3% after CT, P < 0.05). The gain of Vmax was correlated with the gain of TTE and the gain of Vo2max with IT. The gain of Qmax was also correlated with the gain of VO2max. These results suggest that fluctuations of workload and oxygen uptake during training sessions, rather than exercise duration or global energy expenditure, are key factors in improving muscle oxidative capacities. In an integrative view, IT seems optimal in maximizing both peripheral muscle and central cardiorespiratory adaptations, permitting significant functional improvement. These data support the symmorphosis concept in sedentary subjects.
|
|
| 7. |
- Daussin, Frédéric N, et al.
(author)
-
Improvement of VO2max by cardiac output and oxygen extraction adaptation during intermittent versus continuous endurance training
- 2007
-
In: European Journal of Applied Physiology. - New York, USA : Springer. - 1439-6319 .- 1439-6327. ; 101:3, s. 377-83
-
Journal article (peer-reviewed)abstract
- Improvement of exercise capacity by continuous (CT) versus interval training (IT) remains debated. We tested the hypothesis that CT and IT might improve peripheral and/or central adaptations, respectively, by randomly assigning 10 healthy subjects to two periods of 24 trainings sessions over 8 weeks in a cross-over design, separated by 12 weeks of detraining. Maximal oxygen uptake (VO2max), cardiac output (Qmax) and maximal arteriovenous oxygen difference (Da-vO2max) were obtained during an exhaustive incremental test before and after each training period. VO2max and Qmax increased only after IT (from 26.3 +/- 1.6 to 35.2 +/- 3.8 ml min(-1) kg(-1) and from 17.5 +/- 1.3 to 19.5 +/- 1.8 l min(-1), respectively; P < 0.01). Da-vO2max increased after both protocols (from 11.0 +/- 0.8 to 12.7 +/- 1.0; P < 0.01 and from 11.0 +/- 0.8 to 12.1 +/- 1.0 ml 100 ml(-1), P < 0.05 in CT and IT, respectively). At submaximal intensity a significant rightward shift of the Q/Da-vO2 relationship appeared only after CT. These results suggest that in isoenergetic training, central and peripheral adaptations in oxygen transport and utilization are training-modality dependant. IT improves both central and peripheral components of Da-vO2max whereas CT is mainly associated with greater oxygen extraction.
|
|
| 8. |
- Daussin, Frederic, et al.
(author)
-
Training at high exercise intensity promotes qualitative adaptations of mitochondrial function in human skeletal muscle
- 2008
-
In: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 104:5, s. 1436-1441
-
Journal article (peer-reviewed)abstract
- This study explored mitochondrial capacities to oxidize carbohydrate and fatty acids and functional optimization of mitochondrial respiratory chain complexes in athletes who regularly train at high exercise intensity (ATH, n = 7) compared with sedentary (SED, n = 7). Peak O(2) uptake (Vo(2max)) was measured, and muscle biopsies of vastus lateralis were collected. Maximal O(2) uptake of saponin-skinned myofibers was evaluated with several metabolic substrates [glutamate-malate (V(GM)), pyruvate (V(Pyr)), palmitoyl carnitine (V(PC))], and the activity of the mitochondrial respiratory complexes II and IV were assessed using succinate (V(s)) and N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride (V(TMPD)), respectively. Vo(2max) was higher in ATH than in SED (57.8 +/- 2.2 vs. 31.4 +/- 1.3 ml.min(-1).kg(-1), P < 0.001). V(GM) was higher in ATH than in SED (8.6 +/- 0.5 vs. 3.3 +/- 0.3 micromol O(2).min(-1).g dry wt(-1), P < 0.001). V(Pyr) was higher in ATH than in SED (8.7 +/- 1.0 vs. 5.5 +/- 0.2 micromol O(2).min(-1).g dry wt(-1), P < 0.05), whereas V(PC) was not significantly different (5.3 +/- 0.9 vs. 4.4 +/- 0.5 micromol O(2).min(-1).g dry wt(-1)). V(S) was higher in ATH than in SED (11.0 +/- 0.6 vs. 6.0 +/- 0.3 micromol O(2).min(-1).g dry wt(-1), P < 0.001), as well as V(TMPD) (20.1 +/- 1.0 vs. 16.2 +/- 3.4 micromol O(2).min(-1).g dry wt(-1), P < 0.05). The ratios V(S)/V(GM) (1.3 +/- 0.1 vs. 2.0 +/- 0.1, P < 0.001) and V(TMPD)/V(GM) (2.4 +/- 1.0 vs. 5.2 +/- 1.8, P < 0.01) were lower in ATH than in SED. In conclusion, comparison of ATH vs. SED subjects suggests that regular endurance training at high intensity promotes the enhancement of maximal mitochondrial capacities to oxidize carbohydrate rather than fatty acid and induce specific adaptations of the mitochondrial respiratory chain at the level of complex I.
|
|
| 9. |
- Di Donna, S, et al.
(author)
-
Regenerative capacity of human satellite cells : the mitotic clock in cell transplantation
- 2000
-
In: Neurological Sciences. - New York, USA : Springer-Verlag New York. - 1590-1874 .- 1590-3478. ; 21:5 Suppl, s. S943-51
-
Journal article (peer-reviewed)abstract
- In this communication, we will review the problems caused by cell-mediated gene therapy, taking skeletal muscle as a physiological model. In particular we have utilised vectors transferring telomerase under the control of retroviral promoters into human satellite cells. The set of results presented here has several implications regarding gene therapy trials. Nevertheless, more experiments will be required to fully validate this cellular model and to use telomerase to safely extend the lifespan of putative gene therapy vectors.
|
|
| 10. |
|
|
