骨量-肌量减少性肥胖综合征与2型糖尿病关系的研究进展

随着人口老龄化进程加剧，增龄性疾病发病率增高，多病共存对老年人的健康造成极大危害，探讨骨量-肌量减少性肥胖综合征与2型糖尿病之间的关系可为治疗老年人多病共存提供理论依据。本文就骨量-肌量减少性肥胖综合征与2型糖尿病的关系予以综述，得出二者之间关系密切，相互影响，综合治疗可有效改善整体预后，提高生存质量。     

Skeletal muscle growth defect in human growth hormone transgenic rat is accompanied by phenotypic changes in progenitor cells

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.     

Relationship between Sarcopenic Obesity and Cardiovascular Disease Risk as Estimated by the Framingham Risk Score

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.

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CT评价腹股沟疝患者肌肉质量方法的前瞻性研究

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Reliability of Skeletal Muscle Area Measurement on CT with Different Parameters: A Phantom Study

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