Normative data of muscle fiber diameter of vastus lateralis during childhood: a field test

2019 ◽  
Vol 59 (5) ◽  
pp. 590-593
Author(s):  
Jane Valentine ◽  
Jason Dyke ◽  
Rosyln Ward ◽  
Ashleigh Thornton ◽  
Eve Blair ◽  
...  
Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1655
Author(s):  
Tao Tang ◽  
Jinhai Bai ◽  
Zhipeng Ao ◽  
Zehong Wei ◽  
Yi Hu ◽  
...  

The present study investigated the effects of dietary paper mulberry (Broussonetia Papyrifera, BP) on growth performance, muscle quality and muscle growth-related mRNA expressions of grass carp. Fish (initial weight: 50.0 ± 0.5 g) were fed diets supplemented with 0% (control diet), 5%, 10%, 15% and 20% BP for 8 weeks. The results showed that increasing levels of paper mulberry linearly and quadratically decreased the special gain rate (SGR) and increased the feed conversion rate (FCR) of grass carp (p < 0.05). Significantly positive quadratic trends were found between paper mulberry levels and muscle crude fat or crude protein of grass carp (p < 0.05). In comparison to the control diet, the 10%BP and 15%BP groups had significantly decreased muscle crude fat and increased crude protein (p < 0.05). The levels of paper mulberry resulted in a linear and quadratic increase in water loss of grass carp muscle (p < 0.05), and all groups with paper mulberry supplementation were significantly higher than the control group (p < 0.05). Significant positive linear and quadratic trends were found between the paper mulberry levels and muscle fiber diameter or density of grass carp (p < 0.05). In comparison to the control diet, the significant differences were found in the 15%BP and 20%BP groups (p < 0.05). The muscle adhesiveness and hardness linearly and quadratically increased with the increasing levels of paper mulberry (p < 0.05), and both of which increased significantly when the level of paper mulberry reached 10% (p < 0.05). In addition, the increase in paper mulberry linearly and quadratically improved the expressions of myoblast determination protein (MyoD), myogenin (MyoG), paired box protein 7 (Pax7) and myostatin 1 (MSTN1) (p < 0.05). When the supplementation of paper mulberry reached 15%, the expressions of all these mRNAs were significantly higher than those of the control group (p < 0.05). In summary, adding 5% paper mulberry did not affect the growth of grass carp. However, the supplementation of 10% paper mulberry could improve muscle quality through improving muscle hardness, reducing fat accumulation and muscle fiber diameter, at the cost of reducing growth performance.


1992 ◽  
Vol 73 (3) ◽  
pp. 812-816 ◽  
Author(s):  
A. Aniansson ◽  
G. Grimby ◽  
M. Hedberg

Muscle strength and muscle morphology have been studied three times during a period of 11 yr in nine elderly men. On the last occasion the average age was 80.4 (range 79–82) yr. Body cell mass decreased by 6% and muscle strength for knee extension, measured by means of isometric and concentric isokinetic (30–60 degrees/s) recordings, declined by 25–35% over the 11-yr period. Between 76 and 80 yr of age only the isokinetic strength for 30 degrees/s decreased significantly. Muscle fiber composition in the vastus lateralis did not change between 69 and 76 yr of age, but there was a significant reduction in the proportion of type IIb fibers from 76 to 80 yr. The decrease in type II fiber areas was not significant between 69 and 76 yr of age (as in a larger sample from the same population), but a significant increase in both type I and type II fiber areas was recorded from 76 to 80 yr of age and biceps brachii showed similar tendencies. In the same period, the enzymatic activities of myokinase and lactate dehydrogenase subsided in the vastus lateralis, but there was no change for triose phosphate dehydrogenase, 3-hydroxy-CoA-dehydrogenase, and citrate synthase. The muscle fiber hypertrophy in this group of elderly men with maintained physical activity between 76 and 80 yr of age is interpreted as a compensatory adaptation for the loss of motor units. In addition, the adaptation with respect to oxidative capacities seems to be maintained at this age.


Author(s):  
Seyedeh Zahra Hosseini Sisi ◽  
Mohammad Ali Azarbayjani ◽  
Mohammad Reza Vafaeenasab ◽  
Maghsoud Peeri ◽  
Mohammad Reza Dehghani

Introduction: Menopause can change the musculoskeletal system by reducing estrogen hormone levels. The aim of this study was to evaluate the effect of regular resistance training accompanied by vitamins D and calcium supplements during pre-menopausal period on muscle tissues of Wistar rats’ postmenopausal period. Methods: In this experimental study, female Wistar rats were randomly divided into control, placebo, vitamins D, Calcium, excercise, vitamins D- Calcium, vitamins.D- excercise, Calcium - excercise, and vitamins.D‐ Calcium - excercise groups. Control and placebo groups were fed with a standard diet and sesame oil, respectively. The amount of calcium consumed was 35 mg / kg and the amount of vitamin D was 10000 IU during the two-month period, and in the resistance training groups, two months of training was performed with a ladder. Then ovariectomy was done and sample of the gastrocnemius muscle was taken and the diameter of muscle fiber, the number of muscle and adipocyte cell as well as the number of inflammatory cells were studied. The statistical analysis by means of one-way ANOVA and SPSS version 20 was performed. Results: Compared to the control group, the increase in the number of adipocyte cells were observed in the vitamin D, calcium-vitamin D, vitamin D-resistance exercise and placebo groups but it was not significantly different. Muscle fiber diameter significantly increased in all groups compared to the control group (P <0.001). The number of muscle cells increased significantly in the calcium-resistance exercise group (103± 9), vitamin D-resistance exercise (105 ±6.9) and calcium-vitamin D-resistance exercise (114 ± 3.16) compared to the control group, while, there was a significant increase in inflammatory cells only in the control and placebo groups (p≤0.05). Conclusion: Regular resistance exercise accompanied with vitamin D and Calcium supplements in premenopausal period can improve muscle fiber diameter and muscle cell numbers; in addition, the process of decrease in the muscle strength and muscle inflammation during menopause will be delayed.


2019 ◽  
Vol 130 (7) ◽  
pp. e85
Author(s):  
Imran Goker ◽  
Mehmet Baris Baslo ◽  
Peyman Mahouti

1996 ◽  
Vol 80 (3) ◽  
pp. 1061-1064 ◽  
Author(s):  
D. Constantin-Teodosiu ◽  
S. Howell ◽  
P. L. Greenhaff

The effect of prolonged exhaustive exercise on free carnitine and acetylcarnitine concentrations in mixed-fiber skeletal muscle and in type I and II muscle fibers was investigated in humans. Needle biopsy samples were obtained from the vastus lateralis of six subjects immediately after exhaustive one-legged cycling at approximately 75% of maximal O2 uptake from both the exercised and nonexercised (control) legs. In the resting (control) leg, there was no difference in the free carnitine concentration between type I and II fibers (20.36 +/- 1.25 and 20.51 +/- 1.16 mmol/kg dry muscle, respectively) despite the greater potential for fat oxidation in type I fibers. However, the acetylcarnitine concentration was slightly greater in type I fibers (P < 0.01). During exercise, acetylcarnitine accumulation occurred in both muscle fiber types, but accumulation was greatest in type I fibers (P < 0.005). Correspondingly, the concentration of free carnitine was significantly lower in type I fibers at the end of exercise (P < 0.001). The sum of free carnitine and acetylcarnitine concentrations in type I and II fibers at rest was similar and was unchanged by exercise. In conclusion, the findings of the present study support the suggestion that carnitine buffers excess acetyl group formation during exercise and that this occurs in both type I and II fibers. However, the greater accumulation of acetylcarnitine in type I fibers during prolonged exercise probably reflects the greater mitochondrial content of this fiber type.


2012 ◽  
Vol 83 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Charles Widmer ◽  
Vo Danh Nguyen ◽  
Harmeet Chiang ◽  
Joyce Morris-Wiman

Abstract Objective: To determine changes in mouse myosin heavy chain (MyHC) protein expression that may occur with a clinically relevant vertical dimension of occlusion (VDO) increase. Materials and Methods: Six CD-1 male mice (age: 6 weeks) underwent a 10% bite opening to replicate the clinical condition using composite on the maxillary molars and were compared to six age-matched controls. Mice were sacrificed at day 7 and 14 after bite opening. A representative masseter transverse cryosection from each animal was examined in selected sampling regions (anterior, posterior, posterior-deep, and posterior-intermediate) to assay fiber phenotype proportions and fiber size. Results: In control masseter muscles, the proportion of muscle fibers containing MyHC IIb increased in the posterior-intermediate and posterior-deep regions between 7 and 14 days (ANOVA, P &lt; .05). The increase in the proportion of MyHC IIb fibers in the bite opening group did not occur when compared to the control group (P &lt; .05). In addition, after 14 days of bite opening, the proportion of fibers positive for MyHC IIa was decreased in the anterior region compared to control masseter muscles. Muscle fiber diameter remained unchanged in both groups (experimental and control) and over time (P &gt; .10). Conclusion: These data are consistent with a selective plasticity of the expression of MyHC IIb protein in the deep regions of the male masseter muscle in response to a clinically relevant VDO increase.


Genes ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1012
Author(s):  
Thomas Yvert ◽  
Eri Miyamoto-Mikami ◽  
Takuro Tobina ◽  
Keisuke Shiose ◽  
Ryo Kakigi ◽  
...  

PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms have been associated with endurance athlete status, endurance performance phenotypes, and certain health-related markers of different pathologies such as metabolic syndrome, diabetes, and dyslipidemia. We hypothesized that they could be considered interesting candidates for explaining inter-individual variations in muscle fiber composition in humans. We aimed to examine possible associations of these polymorphisms with myosin heavy-chain (MHC) isoforms as markers of muscle fiber compositions in vastus lateralis muscle in a population of 214 healthy Japanese subjects, aged between 19 and 79 years. No significant associations were found in men for any measured variables. In contrast, in women, the PPARGC1A rs8192678 A/A genotype was significantly associated with a higher proportion of MHC-I (p = 0.042) and with a lower proportion of MHC-IIx (p = 0.033), and the NRF1 rs6949152 AA genotype was significantly associated with a higher proportion of MHC-I (p = 0.008) and with a lower proportion of MHC IIx (p = 0.035). In women, the genotype scores of the modes presenting the most significant results for PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms were significantly associated with MHC-I (p = 0.0007) and MHC IIx (p = 0.0016). That is, women with combined PPARGC1A A/A and NRF1 A/A genotypes presented the highest proportion of MHC-I and the lowest proportion of MHC-IIx, in contrast to women with combined PPARGC1A GG+GA and NRF1 AG+GG genotypes, who presented the lowest proportion of MHC-I and the highest proportion of MHC-IIx. Our results suggest possible associations between these polymorphisms (both individually and in combination) and the inter-individual variability observed in muscle fiber composition in women, but not in men.


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