Many studies have investigated the relationship between angiotensin-converting enzyme (ACE) D/I p... more Many studies have investigated the relationship between angiotensin-converting enzyme (ACE) D/I polymorphism and cardiovascular disease or endothelial dysfunction; however, hardly any of these studies has taken aging or menopause into consideration. Furthermore, despite that many studies have examined the regulatory effects of endothelial-released factors (ERFs) on endothelial function, no study has evaluated the relationship between ERFs and endothelial function with respect to ACE D/I polymorphism and menopause status. To answer these questions, 391 healthy Chinese women over a wide range of ages (22-75 years) were enrolled and divided into premenopause group and post-menopause group. After ACE D/I genotype being identified, the women were then classified into either DI/II or DD genotype. Flow-mediated dilatation (FMD) of brachial endothelium and plasma levels of ERFs: nitric oxide (NO), endothelin-1 (ET-1), and angiotensin II (Ang II) were measured. The results showed that frequencies of ACE D/I genotypes were in accordance with the Hardy-Weinberg equilibrium, and the frequency of I allele was higher than D allele. In pre-menopause group, FMD was significantly higher in women of DI/II than DD (P = 0.032), and agedependent in both genotypes (DD, P = 0.0472; DI/II, P < 0.0001). In post-menopause group, FMD was similar between women of DI/II and DD, and age-dependent only in women of DI/II (P < 0.0001). In pre-menopause group, Ang II level was significantly higher in women of DD than DI/II (P = 0.029), and FMD was significantly correlated with all ERFs in women of DD (NO, P = 0.032; ET-1, P = 0.017; Ang II, P = 0.002), but only with Ang II in women of DI/II (P = 0.026). In post-menopause group, no significant difference was observed in any ERF between women of DI/II and DD, and FMD was only significantly correlated with ET-1 in women of DD (P = 0.010). In summary, FMD in women of DI/II was superior to DD in pre-menopause and more age-dependent than DD in post-menopause, and FMD was closely associated with ERFs. In conclusion, Chinese women of DI/II seem to have lower risk than DD in pre-menopause, but similar risk as DD in post-menopause in developing cardiovascular disease.
Experimental studies favour that tachykinins are involved in the process of myositis and muscle d... more Experimental studies favour that tachykinins are involved in the process of myositis and muscle derangement in an overuse animal model
Unilateral strength training can cause cross-transfer strength effects to the homologous contrala... more Unilateral strength training can cause cross-transfer strength effects to the homologous contralateral muscles. However, the impact of the cross-over effects on the muscle tissue is unclear. To test the hypothesis that unilateral muscle overuse causes bilateral alterations in muscle fiber composition and vascular supply, we have used an experimental rabbit model with unilateral unloaded overstrain exercise via electrical muscle stimulation (E/EMS). The soleus (SOL) and gastrocnemius (GA) muscles of both exercised (E) and contralateral nonexercised (NE) legs (n524) were morphologically analyzed after 1w, 3w and 6w of EMS. Non-exercised rabbits served as controls (n56). After unilateral intervention the muscles of both E and NE legs showed myositis and structural and molecular tissue changes that to various degrees mirrored each other. The fiber area was bilaterally smaller than in controls after 3w of E/EMS in both SOL (E 4420 and NE 4333 mm 2 vs. 5183 mm 2 , p,0.05) and GA (E 3572 and NE 2983 mm 2 vs. 4697 mm 2 , p,0.02) muscles. After 6w of E/EMS, the percentage of slow MyHCI fibers was lower than in controls in the NE legs of SOL (88.1% vs. 98.1%, p,0.009), while the percentage of fast MyHCIIa fibers was higher in the NE legs of GA (25.7% vs. 15.8%, p50.02). The number of capillaries around fibers in the E and NE legs was lower (SOL 13% and 15%, respectively, GA 25% and 23%, respectively, p,0.05) than in controls. The overall alterations were more marked in the fast GA muscle than in the slow SOL muscle, which on the other hand showed more histopathological muscle changes. We conclude that unilateral repetitive unloaded overuse exercise via EMS causes myositis and muscle changes in fiber type proportions, fiber area and fiber capillarization not only in the exercised leg, but also in the homologous muscles in the non-exercised leg.
Lack of staining for desmin in muscles in animal models of eccentric exercise has been suggested ... more Lack of staining for desmin in muscles in animal models of eccentric exercise has been suggested to reflect disruption of the desmin intermediate filament network and proposed to cause disruption of the myofibrillar apparatus and deterioration of muscle fibers. In a recent study, we examined muscle biopsies from persons who had performed different eccentric exercise protocols, which induced delayed onset muscle soreness (DOMS). We were unable to verify that loss of staining for desmin was a feature of sore muscles. Nevertheless, we observed changes in the desmin cytoskeleton, but the meaning of the observations was not conclusive. In the present study, a high resolution immunocytochemical method was used to investigate the changes of desmin and actin in human muscles following a bout of eccentric exercise that lead to DOMS 2-3 days post-exercise. Biopsies were taken before exercise and 1 h and 2-3 and 7-8 days after exercise. Phalloidin, a ligand that labels filamentous actin, and anti-desmin antibodies were used to stain semithin (approximately 0.5 µm) cryosections. At 1 h post-exercise, the staining of actin and desmin did not differ from the controls, whereas in biopsies taken 2-3 and 7-8 days after exercise, 12.5% (SD 5.8%) and 6.1% (SD 2.3%) fibers showed areas of increased staining for actin. Corresponding values for fibers with increased staining for both actin and desmin were 8.7% (SD 3.9%) and 11.4% (SD 4.6%), respectively. We suggest that the increased staining of actin and desmin reflects an increased synthesis of these proteins as part of an adaptation process following the unaccustomed eccentric exercise.
Myofibrillar remodelling with insertion of sarcomeres is a typical feature of biopsies taken from... more Myofibrillar remodelling with insertion of sarcomeres is a typical feature of biopsies taken from persons suffering of exercise-induced delayed onset muscle soreness. Here we studied the presence of the sarcomeric protein myotilin in eccentric exercise related lesions. Myotilin is a component of sarcomeric Z-discs and it binds several other Z-disc proteins, i.e. a-actinin, filamin C, F-actin and FATZ. Myotilin has previously been shown to be present in nemaline rods and central cores and to be mutated in limb girdle muscular dystrophy 1A (LGMD1A) and in a subset of myofibrillar myopathies, indicating an important role in Z-disc maintenance. Our findings on non-diseased muscle affected by eccentric exercise give new information on how myotilin is associated to myofibrillar components upon remodelling. We show that myotilin was present in increased amount in lesions related to Z-disc streaming and events leading to insertion of new sarcomeres in pre-existing myofibrils and can therefore be used as a marker for myofibrillar remodelling. Interestingly, myotilin is preferentially associated with F-actin rather than with the core Z-disc protein a-actinin during these events. This suggests that myotilin has a key role in the dynamic molecular events mediating myofibrillar assembly in normal and diseased skeletal muscle.
The myofibrillar and cytoskeletal alterations observed in delayed onset muscle soreness (DOMS) ca... more The myofibrillar and cytoskeletal alterations observed in delayed onset muscle soreness (DOMS) caused by eccentric exercise are generally considered to represent damage. By contrast our recent immunohistochemical studies suggested that the alterations reflect myofibrillar remodeling (Yu and Thornell 2002; Yu et al. 2003). In the present study the same human muscle biopsies were further analyzed with transmission electron microscopy and immunoelectron microscopy. We show that the ultrastructural hallmarks of DOMS, Z-disc streaming, Z-disc smearing, and Z-disc disruption were present in the biopsies and were significantly more frequent in biopsies taken 2-3 days and 7-8 days after exercise than in those from controls and 1 h after exercise. Four main types of changes were observed: amorphous widened Z-discs, amorphous sarcomeres, double Z-discs, and supernumerary sarcomeres. We confirm by immunoelectron microscopy that the main Z-disc protein alpha-actinin is not present in Z-disc alterations or in the links of electron-dense material between Z-discs in longitudinal register. These alterations were related to an increase of F-actin and desmin, where F-actin was present within the strands of amorphous material. Desmin, on the other hand, was seen in less dense regions of the alterations. Our results strongly support that the myofibrillar and cytoskeletal alterations, considered to be the hallmarks of DOMS, reflect an adaptive remodeling of the myofibrils.
It is well established that unilateral exercise can produce contralateral effects. However, it is... more It is well established that unilateral exercise can produce contralateral effects. However, it is unclear whether unilateral exercise that leads to muscle injury and inflammation also affects the homologous contralateral muscles. To test the hypothesis that unilateral muscle injury causes contralateral muscle changes, an experimental rabbit model with unilateral muscle overuse caused by a combination of electrical muscle stimulation and exercise (EMS/E) was used. The soleus and gastrocnemius muscles of both exercised and non-exercised legs were analyzed with enzyme-and immunohistochemical methods after 1, 3 and 6 weeks of repeated EMS/E. After 1 w of unilateral EMS/E there were structural muscle changes such as increased variability in fiber size, fiber splitting, internal myonuclei, necrotic fibers, expression of developmental MyHCs, fibrosis and inflammation in the exercised soleus muscle. Only limited changes were found in the exercised gastrocnemius muscle and in both non-exercised contralateral muscles. After 3 w of EMS/E, muscle fiber changes, presence of developmental MyHCs, inflammation, fibrosis and affections of nerve axons and AChE production were observed bilaterally in both the soleus and gastrocnemius muscles. At 6 w of EMS/E, the severity of these changes significantly increased in the soleus muscles and infiltration of fat was observed bilaterally in both the soleus and the gastrocnemius muscles. The affections of the muscles were in all three experimental groups restricted to focal regions of the muscle samples. We conclude that repetitive unilateral muscle overuse caused by EMS/E overtime leads to both degenerative and regenerative tissue changes and myositis not only in the exercised muscles, but also in the homologous non-exercised muscles of the contralateral leg. Although the mechanism behind the contralateral changes is unclear, we suggest that the nervous system is involved in the cross-transfer effects.
Using proteomics combined with immunohistochemistry (IHC), we re-evaluated our previous hypothesi... more Using proteomics combined with immunohistochemistry (IHC), we re-evaluated our previous hypothesis that voluntary eccentric exercise does not result in inflammation or necrosis while it does lead to muscular adaptation/remodeling through Z-band related proteins. Muscle biopsies from m. vastus lateralis were taken from five control and five exercised subjects 48 h after 45 min of downhill running. General muscle morphology was examined using histology and histochemistry. Proteomics was used to reveal protein profiles and novel proteins. IHC with specific antibody against three Z-band related proteins identified by proteomics was also performed. General morphology showed no muscle degeneration or inflammation in any exercised biopsy. Proteomics revealed that out of 612 individual protein spots, the exercised biopsy presented three proteins with significant (p \ 0.05) higher expression ratio and four proteins of lower ratio compared to controls. Four of the proteins desmin, actin, Rab-35 and LDB3 are Z-band related; the former two have long been the focus of interest and were found to be up-regulated in the study; the latter two are Z-band assembly/stabilization protein and were for the first time observed to be downregulated in exercised muscles. The other three proteins are related with either cellular metabolism or calcium homeostasis and none is related with muscle necrosis or inflammation. IHC observations that both desmin and actin were increased whereas LDB3 was completely absent in some focal areas are consistent with proteomic results and with our previous observations. The results of the study confirmed our previous findings and therefore strengthened the hypothesis that voluntary eccentric exercise does not cause human muscle necrosis or inflammation; instead, muscular remodeling occurs specifically through Z-band related proteins.
Journal of Sports Medicine and Physical Fitness, Jun 1, 2020
BACKGROUND We have previously evaluated muscle functions and morphology in power athletes of long... more BACKGROUND We have previously evaluated muscle functions and morphology in power athletes of long term (5 to15 years) abuse of anabolic androgen steroids (AAS; Doped) and in clean power athletes (Clean), and observed significant improvements in both muscle morphology and muscle functions in Doped. To our knowledge, the effects of long term AAS abuse on human muscle protein profile have never been studied. METHODS The study examined further the muscle biopsies using a two-dimensional difference gel electrophoresis (2D DIGE) for proteomic screening and protein expression. Cellular localization/distribution of specific proteins identified by proteomic analysis was examined using immunohistochemistry (IHC). RESULTS Different protein profiles were observed between Doped and Clean, and a valid orthogonal projection of latent structure discriminant analysis model was built (N = 16, X = 5, R2 = 0.88/Q2 = 0.84, p = 0.0005), which separated Doped from Clean. Liquid chromatography followed by tandem spectrometry identified 14 protein spots (representing nine different proteins) of significant difference in relative quantity (p < 0.05), of which nine spots were down-regulated in Doped compared with Clean. IHC revealed no significant alteration in cellular localization in phosphoglucomutase-1 and heat shock protein beta-1, but indeed in two reference proteins desmin and F-actin in Doped. CONCLUSIONS Long term abuse of AAS in combination with training is potentially associated with alterations in skeletal muscle protein profile and protein expression, and structural proteins rather than non-structural proteins are preferentially affected in cellular localization/distribution.
International Journal of Environmental Research and Public Health
Lipids play an important role in coordinating and regulating metabolic and inflammatory processes... more Lipids play an important role in coordinating and regulating metabolic and inflammatory processes. Sprint interval training (SIT) is widely used to improve sports performance and health outcomes, but the current understanding of SIT-induced lipid metabolism and the corresponding systemic inflammatory status modification remains controversial and limited, especially in male adolescents. To answer these questions, twelve untrained male adolescents were recruited and underwent 6 weeks of SIT. The pre- and post-training testing included analyses of peak oxygen consumption (VO2peak), biometric data (weight and body composition), serum biochemical parameters (fasting blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol, testosterone, and cortisol), inflammatory markers, and targeted lipidomics. After the 6-week SIT, the serum C-reactive protein (CRP), interleukin (IL)-1β, IL-2, IL-4, IL-10, tumor necrosis factor (TNF)...
Shen-Qi preparation containing ginseng and astragalus as main ingredients was taken by twelve spo... more Shen-Qi preparation containing ginseng and astragalus as main ingredients was taken by twelve sportsmen during six weeks running training. The aerobic capacity of the sportsmen, strength and accumulation of lactic acid in the blood were examined. The results showed that lactic acid can be cleaned up faster in the period of recovery, and BUN level was lower after a long time running in the subjects.
Shen-Qi preparation compounded using ginseng and astragalus as main ingre dients was taken by twe... more Shen-Qi preparation compounded using ginseng and astragalus as main ingre dients was taken by twelve sportsmen six weeks running.The aerobic working capacity of the sportsmen strengthen and accumulation of lactic acid in the body decrease.Lactic acid can be clean up fast in the period of recovery,and BUN level decrease after the sportsmen exercise for a long time
本文采用２种不同的运动强度对受试者进行６周的运动训练，并在训练的不同阶段进行剧烈运动，测定了运动前后反映红细胞老化状态的各项指标：膜ＭＤＡ含量、Ｎａ，Ｋ－ＡＴＰａｓｅ活性、ＳＯＤ活性以及红细胞唾... more 本文采用２种不同的运动强度对受试者进行６周的运动训练，并在训练的不同阶段进行剧烈运动，测定了运动前后反映红细胞老化状态的各项指标：膜ＭＤＡ含量、Ｎａ，Ｋ－ＡＴＰａｓｅ活性、ＳＯＤ活性以及红细胞唾液酸含量。结果表明，不同强度的运动训练均引起血液系统中年轻红细胞比例上升，但影响的程度有所差异。不同训练阶段进行剧烈运动，由于血液系统对训练的适应状态不同，其影响也有所不同，但剧烈运动的结果仍引起红细 ...
运动员是贫血发生的高危人群，研究运动性贫血发生、发展的规律并采取相应的措施预防运动性贫血的发生一直是许多研究者所关心的问题。本文综述了国内外这方面的研究成果，从三个方面加以系统的论述，以期为进一... more 运动员是贫血发生的高危人群，研究运动性贫血发生、发展的规律并采取相应的措施预防运动性贫血的发生一直是许多研究者所关心的问题。本文综述了国内外这方面的研究成果，从三个方面加以系统的论述，以期为进一步的研究提供有益的线索。
Many studies have investigated the relationship between angiotensin-converting enzyme (ACE) D/I p... more Many studies have investigated the relationship between angiotensin-converting enzyme (ACE) D/I polymorphism and cardiovascular disease or endothelial dysfunction; however, hardly any of these studies has taken aging or menopause into consideration. Furthermore, despite that many studies have examined the regulatory effects of endothelial-released factors (ERFs) on endothelial function, no study has evaluated the relationship between ERFs and endothelial function with respect to ACE D/I polymorphism and menopause status. To answer these questions, 391 healthy Chinese women over a wide range of ages (22-75 years) were enrolled and divided into premenopause group and post-menopause group. After ACE D/I genotype being identified, the women were then classified into either DI/II or DD genotype. Flow-mediated dilatation (FMD) of brachial endothelium and plasma levels of ERFs: nitric oxide (NO), endothelin-1 (ET-1), and angiotensin II (Ang II) were measured. The results showed that frequencies of ACE D/I genotypes were in accordance with the Hardy-Weinberg equilibrium, and the frequency of I allele was higher than D allele. In pre-menopause group, FMD was significantly higher in women of DI/II than DD (P = 0.032), and agedependent in both genotypes (DD, P = 0.0472; DI/II, P < 0.0001). In post-menopause group, FMD was similar between women of DI/II and DD, and age-dependent only in women of DI/II (P < 0.0001). In pre-menopause group, Ang II level was significantly higher in women of DD than DI/II (P = 0.029), and FMD was significantly correlated with all ERFs in women of DD (NO, P = 0.032; ET-1, P = 0.017; Ang II, P = 0.002), but only with Ang II in women of DI/II (P = 0.026). In post-menopause group, no significant difference was observed in any ERF between women of DI/II and DD, and FMD was only significantly correlated with ET-1 in women of DD (P = 0.010). In summary, FMD in women of DI/II was superior to DD in pre-menopause and more age-dependent than DD in post-menopause, and FMD was closely associated with ERFs. In conclusion, Chinese women of DI/II seem to have lower risk than DD in pre-menopause, but similar risk as DD in post-menopause in developing cardiovascular disease.
Experimental studies favour that tachykinins are involved in the process of myositis and muscle d... more Experimental studies favour that tachykinins are involved in the process of myositis and muscle derangement in an overuse animal model
Unilateral strength training can cause cross-transfer strength effects to the homologous contrala... more Unilateral strength training can cause cross-transfer strength effects to the homologous contralateral muscles. However, the impact of the cross-over effects on the muscle tissue is unclear. To test the hypothesis that unilateral muscle overuse causes bilateral alterations in muscle fiber composition and vascular supply, we have used an experimental rabbit model with unilateral unloaded overstrain exercise via electrical muscle stimulation (E/EMS). The soleus (SOL) and gastrocnemius (GA) muscles of both exercised (E) and contralateral nonexercised (NE) legs (n524) were morphologically analyzed after 1w, 3w and 6w of EMS. Non-exercised rabbits served as controls (n56). After unilateral intervention the muscles of both E and NE legs showed myositis and structural and molecular tissue changes that to various degrees mirrored each other. The fiber area was bilaterally smaller than in controls after 3w of E/EMS in both SOL (E 4420 and NE 4333 mm 2 vs. 5183 mm 2 , p,0.05) and GA (E 3572 and NE 2983 mm 2 vs. 4697 mm 2 , p,0.02) muscles. After 6w of E/EMS, the percentage of slow MyHCI fibers was lower than in controls in the NE legs of SOL (88.1% vs. 98.1%, p,0.009), while the percentage of fast MyHCIIa fibers was higher in the NE legs of GA (25.7% vs. 15.8%, p50.02). The number of capillaries around fibers in the E and NE legs was lower (SOL 13% and 15%, respectively, GA 25% and 23%, respectively, p,0.05) than in controls. The overall alterations were more marked in the fast GA muscle than in the slow SOL muscle, which on the other hand showed more histopathological muscle changes. We conclude that unilateral repetitive unloaded overuse exercise via EMS causes myositis and muscle changes in fiber type proportions, fiber area and fiber capillarization not only in the exercised leg, but also in the homologous muscles in the non-exercised leg.
Lack of staining for desmin in muscles in animal models of eccentric exercise has been suggested ... more Lack of staining for desmin in muscles in animal models of eccentric exercise has been suggested to reflect disruption of the desmin intermediate filament network and proposed to cause disruption of the myofibrillar apparatus and deterioration of muscle fibers. In a recent study, we examined muscle biopsies from persons who had performed different eccentric exercise protocols, which induced delayed onset muscle soreness (DOMS). We were unable to verify that loss of staining for desmin was a feature of sore muscles. Nevertheless, we observed changes in the desmin cytoskeleton, but the meaning of the observations was not conclusive. In the present study, a high resolution immunocytochemical method was used to investigate the changes of desmin and actin in human muscles following a bout of eccentric exercise that lead to DOMS 2-3 days post-exercise. Biopsies were taken before exercise and 1 h and 2-3 and 7-8 days after exercise. Phalloidin, a ligand that labels filamentous actin, and anti-desmin antibodies were used to stain semithin (approximately 0.5 µm) cryosections. At 1 h post-exercise, the staining of actin and desmin did not differ from the controls, whereas in biopsies taken 2-3 and 7-8 days after exercise, 12.5% (SD 5.8%) and 6.1% (SD 2.3%) fibers showed areas of increased staining for actin. Corresponding values for fibers with increased staining for both actin and desmin were 8.7% (SD 3.9%) and 11.4% (SD 4.6%), respectively. We suggest that the increased staining of actin and desmin reflects an increased synthesis of these proteins as part of an adaptation process following the unaccustomed eccentric exercise.
Myofibrillar remodelling with insertion of sarcomeres is a typical feature of biopsies taken from... more Myofibrillar remodelling with insertion of sarcomeres is a typical feature of biopsies taken from persons suffering of exercise-induced delayed onset muscle soreness. Here we studied the presence of the sarcomeric protein myotilin in eccentric exercise related lesions. Myotilin is a component of sarcomeric Z-discs and it binds several other Z-disc proteins, i.e. a-actinin, filamin C, F-actin and FATZ. Myotilin has previously been shown to be present in nemaline rods and central cores and to be mutated in limb girdle muscular dystrophy 1A (LGMD1A) and in a subset of myofibrillar myopathies, indicating an important role in Z-disc maintenance. Our findings on non-diseased muscle affected by eccentric exercise give new information on how myotilin is associated to myofibrillar components upon remodelling. We show that myotilin was present in increased amount in lesions related to Z-disc streaming and events leading to insertion of new sarcomeres in pre-existing myofibrils and can therefore be used as a marker for myofibrillar remodelling. Interestingly, myotilin is preferentially associated with F-actin rather than with the core Z-disc protein a-actinin during these events. This suggests that myotilin has a key role in the dynamic molecular events mediating myofibrillar assembly in normal and diseased skeletal muscle.
The myofibrillar and cytoskeletal alterations observed in delayed onset muscle soreness (DOMS) ca... more The myofibrillar and cytoskeletal alterations observed in delayed onset muscle soreness (DOMS) caused by eccentric exercise are generally considered to represent damage. By contrast our recent immunohistochemical studies suggested that the alterations reflect myofibrillar remodeling (Yu and Thornell 2002; Yu et al. 2003). In the present study the same human muscle biopsies were further analyzed with transmission electron microscopy and immunoelectron microscopy. We show that the ultrastructural hallmarks of DOMS, Z-disc streaming, Z-disc smearing, and Z-disc disruption were present in the biopsies and were significantly more frequent in biopsies taken 2-3 days and 7-8 days after exercise than in those from controls and 1 h after exercise. Four main types of changes were observed: amorphous widened Z-discs, amorphous sarcomeres, double Z-discs, and supernumerary sarcomeres. We confirm by immunoelectron microscopy that the main Z-disc protein alpha-actinin is not present in Z-disc alterations or in the links of electron-dense material between Z-discs in longitudinal register. These alterations were related to an increase of F-actin and desmin, where F-actin was present within the strands of amorphous material. Desmin, on the other hand, was seen in less dense regions of the alterations. Our results strongly support that the myofibrillar and cytoskeletal alterations, considered to be the hallmarks of DOMS, reflect an adaptive remodeling of the myofibrils.
It is well established that unilateral exercise can produce contralateral effects. However, it is... more It is well established that unilateral exercise can produce contralateral effects. However, it is unclear whether unilateral exercise that leads to muscle injury and inflammation also affects the homologous contralateral muscles. To test the hypothesis that unilateral muscle injury causes contralateral muscle changes, an experimental rabbit model with unilateral muscle overuse caused by a combination of electrical muscle stimulation and exercise (EMS/E) was used. The soleus and gastrocnemius muscles of both exercised and non-exercised legs were analyzed with enzyme-and immunohistochemical methods after 1, 3 and 6 weeks of repeated EMS/E. After 1 w of unilateral EMS/E there were structural muscle changes such as increased variability in fiber size, fiber splitting, internal myonuclei, necrotic fibers, expression of developmental MyHCs, fibrosis and inflammation in the exercised soleus muscle. Only limited changes were found in the exercised gastrocnemius muscle and in both non-exercised contralateral muscles. After 3 w of EMS/E, muscle fiber changes, presence of developmental MyHCs, inflammation, fibrosis and affections of nerve axons and AChE production were observed bilaterally in both the soleus and gastrocnemius muscles. At 6 w of EMS/E, the severity of these changes significantly increased in the soleus muscles and infiltration of fat was observed bilaterally in both the soleus and the gastrocnemius muscles. The affections of the muscles were in all three experimental groups restricted to focal regions of the muscle samples. We conclude that repetitive unilateral muscle overuse caused by EMS/E overtime leads to both degenerative and regenerative tissue changes and myositis not only in the exercised muscles, but also in the homologous non-exercised muscles of the contralateral leg. Although the mechanism behind the contralateral changes is unclear, we suggest that the nervous system is involved in the cross-transfer effects.
Using proteomics combined with immunohistochemistry (IHC), we re-evaluated our previous hypothesi... more Using proteomics combined with immunohistochemistry (IHC), we re-evaluated our previous hypothesis that voluntary eccentric exercise does not result in inflammation or necrosis while it does lead to muscular adaptation/remodeling through Z-band related proteins. Muscle biopsies from m. vastus lateralis were taken from five control and five exercised subjects 48 h after 45 min of downhill running. General muscle morphology was examined using histology and histochemistry. Proteomics was used to reveal protein profiles and novel proteins. IHC with specific antibody against three Z-band related proteins identified by proteomics was also performed. General morphology showed no muscle degeneration or inflammation in any exercised biopsy. Proteomics revealed that out of 612 individual protein spots, the exercised biopsy presented three proteins with significant (p \ 0.05) higher expression ratio and four proteins of lower ratio compared to controls. Four of the proteins desmin, actin, Rab-35 and LDB3 are Z-band related; the former two have long been the focus of interest and were found to be up-regulated in the study; the latter two are Z-band assembly/stabilization protein and were for the first time observed to be downregulated in exercised muscles. The other three proteins are related with either cellular metabolism or calcium homeostasis and none is related with muscle necrosis or inflammation. IHC observations that both desmin and actin were increased whereas LDB3 was completely absent in some focal areas are consistent with proteomic results and with our previous observations. The results of the study confirmed our previous findings and therefore strengthened the hypothesis that voluntary eccentric exercise does not cause human muscle necrosis or inflammation; instead, muscular remodeling occurs specifically through Z-band related proteins.
Journal of Sports Medicine and Physical Fitness, Jun 1, 2020
BACKGROUND We have previously evaluated muscle functions and morphology in power athletes of long... more BACKGROUND We have previously evaluated muscle functions and morphology in power athletes of long term (5 to15 years) abuse of anabolic androgen steroids (AAS; Doped) and in clean power athletes (Clean), and observed significant improvements in both muscle morphology and muscle functions in Doped. To our knowledge, the effects of long term AAS abuse on human muscle protein profile have never been studied. METHODS The study examined further the muscle biopsies using a two-dimensional difference gel electrophoresis (2D DIGE) for proteomic screening and protein expression. Cellular localization/distribution of specific proteins identified by proteomic analysis was examined using immunohistochemistry (IHC). RESULTS Different protein profiles were observed between Doped and Clean, and a valid orthogonal projection of latent structure discriminant analysis model was built (N = 16, X = 5, R2 = 0.88/Q2 = 0.84, p = 0.0005), which separated Doped from Clean. Liquid chromatography followed by tandem spectrometry identified 14 protein spots (representing nine different proteins) of significant difference in relative quantity (p < 0.05), of which nine spots were down-regulated in Doped compared with Clean. IHC revealed no significant alteration in cellular localization in phosphoglucomutase-1 and heat shock protein beta-1, but indeed in two reference proteins desmin and F-actin in Doped. CONCLUSIONS Long term abuse of AAS in combination with training is potentially associated with alterations in skeletal muscle protein profile and protein expression, and structural proteins rather than non-structural proteins are preferentially affected in cellular localization/distribution.
International Journal of Environmental Research and Public Health
Lipids play an important role in coordinating and regulating metabolic and inflammatory processes... more Lipids play an important role in coordinating and regulating metabolic and inflammatory processes. Sprint interval training (SIT) is widely used to improve sports performance and health outcomes, but the current understanding of SIT-induced lipid metabolism and the corresponding systemic inflammatory status modification remains controversial and limited, especially in male adolescents. To answer these questions, twelve untrained male adolescents were recruited and underwent 6 weeks of SIT. The pre- and post-training testing included analyses of peak oxygen consumption (VO2peak), biometric data (weight and body composition), serum biochemical parameters (fasting blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol, testosterone, and cortisol), inflammatory markers, and targeted lipidomics. After the 6-week SIT, the serum C-reactive protein (CRP), interleukin (IL)-1β, IL-2, IL-4, IL-10, tumor necrosis factor (TNF)...
Shen-Qi preparation containing ginseng and astragalus as main ingredients was taken by twelve spo... more Shen-Qi preparation containing ginseng and astragalus as main ingredients was taken by twelve sportsmen during six weeks running training. The aerobic capacity of the sportsmen, strength and accumulation of lactic acid in the blood were examined. The results showed that lactic acid can be cleaned up faster in the period of recovery, and BUN level was lower after a long time running in the subjects.
Shen-Qi preparation compounded using ginseng and astragalus as main ingre dients was taken by twe... more Shen-Qi preparation compounded using ginseng and astragalus as main ingre dients was taken by twelve sportsmen six weeks running.The aerobic working capacity of the sportsmen strengthen and accumulation of lactic acid in the body decrease.Lactic acid can be clean up fast in the period of recovery,and BUN level decrease after the sportsmen exercise for a long time
本文采用２种不同的运动强度对受试者进行６周的运动训练，并在训练的不同阶段进行剧烈运动，测定了运动前后反映红细胞老化状态的各项指标：膜ＭＤＡ含量、Ｎａ，Ｋ－ＡＴＰａｓｅ活性、ＳＯＤ活性以及红细胞唾... more 本文采用２种不同的运动强度对受试者进行６周的运动训练，并在训练的不同阶段进行剧烈运动，测定了运动前后反映红细胞老化状态的各项指标：膜ＭＤＡ含量、Ｎａ，Ｋ－ＡＴＰａｓｅ活性、ＳＯＤ活性以及红细胞唾液酸含量。结果表明，不同强度的运动训练均引起血液系统中年轻红细胞比例上升，但影响的程度有所差异。不同训练阶段进行剧烈运动，由于血液系统对训练的适应状态不同，其影响也有所不同，但剧烈运动的结果仍引起红细 ...
运动员是贫血发生的高危人群，研究运动性贫血发生、发展的规律并采取相应的措施预防运动性贫血的发生一直是许多研究者所关心的问题。本文综述了国内外这方面的研究成果，从三个方面加以系统的论述，以期为进一... more 运动员是贫血发生的高危人群，研究运动性贫血发生、发展的规律并采取相应的措施预防运动性贫血的发生一直是许多研究者所关心的问题。本文综述了国内外这方面的研究成果，从三个方面加以系统的论述，以期为进一步的研究提供有益的线索。
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