Intramuscular and Liver Triglycerides Are Increased in the Elderly

Texas A&M University - Galveston, Galveston, Texas, United States
Journal of Clinical Endocrinology &amp Metabolism (Impact Factor: 6.21). 09/2004; 89(8):3864-71. DOI: 10.1210/jc.2003-031986
Source: PubMed


Magnetic resonance spectroscopy studies have shown that intramyocellular lipids (IMCL) and liver fat (LFAT) levels vary with insulin sensitivity and obesity, which are common in the elderly. Thus, magnetic resonance spectroscopy was used to investigate the hypothesis that IMCL and LFAT are increased in the elderly. IMCL and LFAT in young (aged 20-32 yr) and elderly (aged 65-74 yr) were measured fasted, and glucose, insulin, total free fatty acids levels, and free fatty acids profiles were measured during a 2-h oral glucose tolerance test. Body fat percentage was determined with dual x-ray absorptiometry. The elderly had significantly greater IMCL (0.12 +/- 0.01 vs. 0.08 +/- 0.01, mean +/- sem; P = 0.01) and LFAT (0.28 +/- 0.06 vs. 0.08 +/- 0.01; P = 0.004; expressed as ratios to Intralipid standard) than the young. The elderly had increased insulin resistance as calculated by the Matsuda model compared with the young (5.1 +/- 0.9 vs. 9.9 +/- 1.4; P = 0.02). Regression analysis of all subjects indicated that the increases in IMCL and LFAT were correlated with insulin sensitivity, glycosylated hemoglobin, plasma lipids, and body fat. Furthermore, the correlation between insulin sensitivity and IMCL and LFAT remained significant, after accounting for the effect of body fat. Increases of IMCL and LFAT occur in elderly individuals and may be related to insulin resistance.

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Available from: Bradley R Newcomer, Oct 05, 2015
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    • "Primary sarcopenia is characterized by an age-related reduction in muscle mass, strength, quality [18-20] and altered metabolism [21]. These changes often include increased intramuscular adipose tissue (adipose tissue within the epimysium (IMAT)) [22-24] and are associated with physical frailty, loss of mobility and increased risk for fractures [25,26]. Furthermore, IMAT infiltration and the density of the skeletal muscle fibers (muscle attenuation) may differentially affect the lower limb musculature [16,21,27]. "
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    ABSTRACT: Impaired balance, loss of mobility and falls are major problems associated with changes in muscle in older adults. However, the extent to which muscle composition and related performance measures for different lower limb muscles are associated with falls in older individuals is unclear. This study evaluated lower limb muscle attenuation, intramuscular adipose tissue (IMAT) infiltration and muscle performance in older fallers and non-fallers. For this cross-sectional study, fifty-eight community dwelling older individuals (>65 years) were classified into fallers (n = 15) or non-fallers (n = 43). Computed tomography (CT) was used to determine muscle attenuation and intramuscular adipose tissue (IMAT) of multiple thigh and hip muscles. Muscle performance was assessed with isokinetic dynamometry. For both groups, Rectus Femoris showed the highest muscle attenuation and lowest IMAT infiltration, and Gluteus Maximus and Gluteus Medius/Minimus muscles had the lowest muscle attenuation and highest IMAT infiltration. Fallers exhibited lower muscle attenuation and higher IMAT infiltration than non-faller participants in most muscles, where the gluteal muscles were the most affected (p < 0.05). Fallers also showed a lower peak hip abduction torque (p < 0.05). There were significant associations (r = 0.31 to 0.53) between joint torques and muscle composition, with the strongest associations between Gluteus Medius/Minimus and hip abduction strength. While fallers were generally differentiated from non-fallers by muscle composition, the most affected muscles were the proximal gluteal muscles of the hip joint accompanied by lower hip abduction strength, which may contribute to impaired balance function and increased risk for falls.
    BMC Geriatrics 03/2014; 14(1):37. DOI:10.1186/1471-2318-14-37 · 1.68 Impact Factor
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    • "With aging there is a greater relative increase in intra-abdominal fat than in subcutaneous fat. In addition, increases in intrahepatic fat in older persons are associated with insulin resistance [25]. It has been suggested that obesity is a strong risk factor for periodontal tissue destruction [26], since adipose tissue represents more than simple fat accumulation, it should be considered as an endocrine organ. "
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    ABSTRACT: In the industrialized part of the world, an increasing number of people live the old age without too many restrictions due to illness or physiological impairment. This group is known as the young elderly. On the contrary, a consistent part of seniors develops a greater number of medical conditions and become more and more dependent, these are the old elderly. The first cause of tooth lost in industrialized word is periodontitis that generally strikes people older than 40 years and determines serious detriment of the stomatognatic organ. Smoking and stress are risk factors for periodontitis that are common and shared between young, adult, and older age. Diabetes mellitus, obesity, and osteoporosis are very frequent pathological situations in older age. They have been identified as cofactors in the progression of periodontitis. Many dental associations recognize the importance of continued research on oral fluids diagnostics and welcome the development of rapid point-of-care tests providing accurate measurements of clinically validated biomarkers. At present, well-studied molecules associated with host response factors and with derived tissue destruction mediators have been proposed as diagnostic biomarkers for periodontitis detected in the oral fluids.
    The Scientific World Journal 12/2013; 2013:127905. DOI:10.1155/2013/127905 · 1.73 Impact Factor
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    • "Elderly humans have the highest prevalence of being overweight and obese (Flegal et al., 2010) together with increased accumulation of fat in ectopic tissues such as the liver (Cree et al., 2004; Bianchi et al., 2010) and skeletal muscle (Cree et al., 2004). Ectopic accumulation of fat is linked to insulin resistance. "
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