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31.
32.
Shingo Shibata Chiori Ueno Tsuyoshi Ito Keitaro Yamanouchi Takashi Matsuwaki Masugi Nishihara 《Age (Dordrecht, Netherlands)》2010,32(2):239-253
Growth hormone (GH) is known to have a pivotal role in the maintenance of skeletal muscle mass. Sarcopenia, the loss of skeletal
muscle mass, is a common phenomenon in aging, and it is widely accepted that sarcopenia is largely attributed to age-related
decline in GH secretion. In the present study, we tested if human growth hormone transgenic rats (GH-TG rats) whose plasma
GH levels are maintained relatively low could be an appropriate model for sarcopenia. Analyses of GH-TG rats revealed that
they exhibit skeletal muscle growth defect as well as atrophy of myofibers. The number of myofibers in tibialis anterior muscle
was comparable to that of WT rats, while the proportion of type I slow myofibers in tibialis anterior muscle was increased
in GH-TG rats after 5 months. Neither increased expression of ubiquitin ligases, MuRF1 and MAFbx, nor indication of apoptotic
cell death was observed. Notably, myogenic differentiation potential of skeletal muscle progenitor cells in GH-TG rats was
lower than WT rats, and this was accompanied by increased adipogenic potential. These results indicate that GH-TG rats could
be a useful model to elucidate the mechanism of sarcopenia induced by reduced GH action and raised the possibility that decreased
GH action may cause an alteration of differentiation potential of skeletal muscle progenitor cells. 相似文献
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This study was conducted to assess the association between sarcopenic obesity and cardiovascular disease (CVD) risk in Korean adults (n=3,320; ≥40 yr) who participated in the 5th Korean National Health and Nutrition Examination Survey in 2010. The appendicular skeletal muscle mass divided by body weight was calculated for each participant; participants with values <1 standard deviation below the mean reference value (i.e., aged 20-39 yr) were considered sarcopenic. Subjects were further classified into 4 groups according to their obesity (i.e., body mass index ≥25 kg/m2) and sarcopenic status. Individuals'' 10-yr CVD risk was determined using the Framingham risk model. The sarcopenic obese group had more participants (43.8% men, 14.6% women) with a high risk of CVD (≥20%). The sarcopenic obese group was associated with an increased 10-yr CVD risk than the non-sarcopenic, non-obese group (odds ratio [OR], 2.49; 95% confidence interval [CI], 1.53-4.06, P<0.001 in men; OR, 1.87; 95% CI, 1.02-3.41, P=0.041 in women). Sarcopenic non-obese and non-sarcopenic obese subjects were not associated with an increased 10-yr CVD risk. Sarcopenic obesity, but not non-sarcopenic obesity, was closely associated with an increased CVD risk in Korean adults.
Graphical Abstract
相似文献35.
36.
目的 应用CT技术评价老年腹股沟疝患者的肌肉质量。方法 拟接受腹股沟疝手术、年龄在70~90岁的男性住院患者30例为研究对象,40~50岁10名男性健康受试者为成人对照组,10名同年龄段接受健康查体老年人为老年对照组,记录一般资料,应用CT技术扫描腹部和大腿,通过专用软件计算相应肌肉面积。结果 研究组握力(36.44±14.15)kg明显少于成人对照组(77.30±22.69)kg (P=0.001),研究组小腿围(25.18±2.31)cm 明显少于成人对照组(27.62±2.33)cm (P=0.006)。CT扫描显示研究组与成人对照组L3(第3腰椎)平面腹部面积、皮下脂肪面积、腹腔脂肪面积和竖脊肌总面积相近,研究组腹部肌肉面积(12 094.23±1 970.30)mm2和竖脊肌肌肉面积(1 642.60±266.90)mm2明显少于成人对照组的(17 462.00±1 600.58)mm2和(2 003.50±350.91)mm2(P=0.001, P=0.007)。L3骨骼肌指数为50.64±7.52,存在肌肉减少症(≤52.4)为66.7 %(20/30)。与同年龄正常查体老人腹部肌肉CT结果相似。研究组下肢骨骼肌面积明显少于成人对照组(P=0.001),下肢脂肪和股骨面积两组比较差异无统计学意义(P>0.05)。结论 老年腹股沟疝患者肌肉质量和力量明显低于成人对照组,CT技术可作为评价工具。 相似文献
37.
目的探讨肌少症和骨质疏松(OP)对RA患者脊柱骨质疏松性骨折(OPF)发生的协同影响.方法选择389例住院的RA患者和同期156例年龄、性别相匹配的健康人,采用双能X线吸收测量(DEXA)法测定腰椎和髋部的骨密度(BMD),采用生物电阻抗法测定四肢骨骼肌质量,摄脊柱X线正侧位片并以半定量法进行脊柱骨折的判定.统计学方法:2组间计量资料比较采用t检验,组间率的比较采用x2检验,2项分类资料的多元回归分析采用Logistic回紧(backward LR法)分析.结果RA患者各测定部位BMD均低于对照组(P<0.01),RA组骨质疏松发生率(128/389,32.9%)高于对照组[(20/156,12.8%),χ^2=22.706,P<0.01];RA患者脊柱OPF发生率为21.6%(84/389),高于对照组中[(3.8%,6/156),χ^2=25.439,P<0.01].RA患者中肌少症的发生率为54.8%,高于对照组[(9.6%,15/156),χ^2=93.241,P<0.01];RA组肌少症合并骨质疏松的发生率(28.5%)高于对照组[(5.8%),χ^2=118.110,P<0.01 ].不同骨量(骨量正常、骨量减少、骨质疏松)分组间RA患者脊柱OPF发生率的差异有统计学意义(χ^2=43.373,P<0.01),且呈现出随着骨量逐渐降低,脊柱OPF发生率逐渐升高的趋势(χ^2=43.003,P<0.01).伴肌少症的RA患者脊柱OPF发生率(27.2%,58/213)高于无肌少症的RA患者[(14.8%,26/176),χ^2=8.833,P=0.003].根据骨质疏松和肌少症分组的3组间(1=无肌少症和骨质疏松;2=单纯肌少症或骨质疏松;3=肌少症合并骨质疏松)RA患者脊柱OPF发生率的差异有统计学意义(χ^2=33.832,P<0.01),且从第1组到第3组脊柱OPF的发生率有逐渐增高的趋势(χ^2=37.164,P<0.01).与未服用糖皮质激素(GC)组相比,服用GC组的RA患者具有更高的肌少症发生率(χ^2=7.136,P=0.008)、OP发生率(CI=10.900,P=0.004)和脊柱OPF发生率(χ^2=20.673,P<0.01).Logistic回归分析显示:高龄[OR(95%CI)=1.069(1.038,1.101),P<0.01]、服用GC[OR(95%CI)=3.169(1.679,5.984),P<0.01]、肌少症和骨质疏松[OR(95%CI)=2.113(1.430,3.124),P<0.01]的同时存在为RA患者发生脊柱OPF的危险因素.结论RA患者肌少症、骨质疏松和脊柱OPF的发生率均明显增高,且肌少症和骨质疏松对RA患者脊柱OPF的发生具有协同作用. 相似文献
38.
Dong Wook Kim Jiyeon Ha Yousun Ko Kyung Won Kim Taeyong Park Jeongjin Lee Myung-Won You Kwon-Ha Yoon Ji Yong Park Young Jin Kee Hong-Kyu Kim 《Korean journal of radiology》2021,22(4):624
ObjectiveTo evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters.Materials and MethodsA phantom, simulating the L2–4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings.ResultsThe skeletal muscle area (threshold, −29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30–150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0–44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used.ConclusionMeasurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality. 相似文献
39.
In the United Kingdom (UK), it is projected that by 2035 people aged >65 years will make up 23 % of the population, with those aged >85 years accounting for 5% of the total population. Ageing is associated with progressive changes in muscle metabolism and a decline in functional capacity, leading to a loss of independence. Muscle metabolic changes associated with ageing have been linked to alterations in muscle architecture and declines in muscle mass and insulin sensitivity. However, the biological features often attributed to muscle ageing are also seen in controlled studies of physical inactivity (e.g. reduced step-count and bed-rest), and it is currently unclear how many of these ageing features are due to ageing per se or sedentarism. This is particularly relevant at a time of home confinements reducing physical activity levels during the Covid-19 pandemic. Current knowledge gaps include the relative contribution that physical inactivity plays in the development of many of the negative features associated with muscle decline in older age. Similarly, data demonstrating positive effects of government recommended physical activity guidelines on muscle health are largely non-existent. It is imperative therefore that research examining interactions between ageing, physical activity and muscle mass and metabolic health is prioritised so that it can inform on the “normal” muscle ageing process and on strategies for improving health span and well-being. This review will focus on important changes in muscle architecture and metabolism that accompany ageing and highlight the likely contribution of physical inactivity to these changes. 相似文献
40.
Jung Hee Kim Sung Hee Choi Soo Lim Ji Won Yoon Seon Mee Kang Ki Woong Kim Jae Young Lim Nam H. Cho Hak Chul Jang 《Journal of Korean medical science》2013,28(7):1041-1047
Age-related body composition changes such as sarcopenia and obesity affect functional decline in the elderly. We investigated the relationship between body composition parameters and functional limitation in older Korean adults. We enrolled 242 men and 231 women aged ≥ 65 yr from the Korean elderly cohort. We used appendicular skeletal muscle mass (ASM) divided by height2 (ASM/Ht2) and ASM divided by weight (ASM/Wt). The isokinetic strength of knee extensor muscles were measured using an isokinetic device. Functional limitations were assessed using the Short Physical Performance Battery (SPPB) score less than nine. Men within the bottom tertile of ASM/Ht2 confer an increased risk for functional limitation compared with those within the top tertile (OR, 6.24; 95% CI, 1.78-22.0). However, in women, subjects within the lowest ASM/Wt tertile had a higher risk compared with those within the highest tertile instead of ASM/Ht2 (OR, 7.60; 95% CI, 2.25-25.7). Leg muscle strength remained the strong measure even after controlling for muscle mass only in women. Only large waist circumference was positively associated with functional limitation only in women. We might consider a different muscle index to assess functional limitation according to the gender. 相似文献