Peripheral Blood T Cell Gene Expression Responses to Exercise and HMB in Sarcopenia.

BACKGROUND: Sarcopenia is a major health problem in older adults. Exercise and nutrient supplementation have been shown to be effective interventions but there are limited studies to investigate their effects on the management of sarcopenia and its possible underlying mechanisms. Here, we studied T cell gene expression responses to interventions in sarcopenia. METHODS: The results of this study were part of a completed trial examining the effectiveness of a 12-week intervention with exercise and nutrition supplementation in community-dwelling Chinese older adults with sarcopenia, based on the available blood samples at baseline and 12 weeks from 46 randomized participants from three study groups, namely: exercise program alone (n = 11), combined-exercise program and nutrition supplement (n = 23), and waitlist control group (n = 12). T cell gene expression was evaluated, with emphasis on inflammation-related genes. Real-time PCR (RT-PCR) was performed on CD3 T cells in 38 selected genes. Correlation analysis was performed to relate the results of gene expression analysis with lower limb muscle strength performance, measured using leg extension tests. RESULTS: Our results showed a significant improvement in leg extension for both the exercise program alone and the combined groups (p < 0.001). Nine genes showed significant pre- and post-difference in gene expression over 12 weeks of intervention in the combined group. Seven genes (RASGRP1, BIN1, LEF1, ANXA6, IL-7R, LRRN3, and PRKCQ) showed an interaction effect between intervention and gene expression levels on leg extension in the confirmatory analysis, with confounder variables controlled and FDR correction. CONCLUSIONS: Our findings showed that T cell-specific inflammatory gene expression was changed significantly after 12 weeks of intervention with combined exercise and HMB supplementation in sarcopenia, and that this was associated with lower limb muscle strength performance.

A Combined Nutrition and Exercise Intervention Influences Serum Vitamin B-12 and 25-Hydroxyvitamin D and Bone Turnover of Healthy Chinese Middle-Aged and Older Adults.

BACKGROUND: Hong Kong faces several public health problems including malnutrition and osteoporosis. Considering the typical Chinese diet and overall low physical activity levels of Chinese adults, timely interventions to improve nutritional status and bone health are needed. OBJECTIVES: We examined the effects of a nutrition plus exercise intervention on serum vitamin B-12 and 25-hydroxyvitamin D [25(OH)D], bone turnover markers, and parathyroid hormone (PTH) concentrations in apparently healthy Chinese middle-aged and older adults. METHODS: In this 24-wk randomized controlled trial, 180 Chinese adults (85 women, mean ± SD age: 61 ± 6 y) were randomly assigned to receive a fortified milk supplement (2 × 30 g/d) and an exercise program (2 × 1 h/wk including resistance, balance, and aerobic training) or no intervention. The primary outcome was physical performance. In this article we analyzed the secondary outcomes serum vitamin B-12 and 25(OH)D concentrations, assessed at baseline, 12 wk, and 24 wk. Also, bone turnover markers and PTH concentrations were studied. Linear mixed models evaluated group differences over time. RESULTS: A significant time × group interaction (P < 0.001) was found for serum vitamin B-12 and 25(OH)D concentrations and the bone turnover markers, but not for serum PTH concentrations (P = 0.09). The intervention increased mean ± SD vitamin B-12 concentrations from baseline (345 ± 119 pmol/L) to 24 wk (484 ± 136 pmol/L), whereas concentrations remained stable within the control. For 25(OH)D concentrations, the intervention group had a greater increase from baseline (54.7 ± 14.2 nmol/L) to 24 wk (80.1 ± 19.2 nmol/L) than the control (60.6 ± 15.2 compared with 65.6 ± 14.6 nmol/L). The ratio of the net effect of bone formation and resorption was greater in the intervention group, suggesting less bone remodeling, irrespective of sex. CONCLUSIONS: A fortified milk supplement and exercise intervention successfully improved vitamin B-12 and 25(OH)D concentrations as well as the balance of bone turnover markers of Chinese middle-aged and older adults.This trial was registered at trialregister.nl as NTR6214.

Randomized Controlled Trial of Exercise and Nutrition Supplementation on Physical and Cognitive Function in Older Chinese Adults Aged 50 Years and Older.

OBJECTIVES: To assess whether a 24-week multidomain lifestyle intervention including a nutritional milk supplement and an exercise program had any effect on physical and cognitive function, self-rated health, and health-related quality of life in older Chinese adults. DESIGN: Randomized controlled trial. SETTING AND PARTICIPANTS: Community-living people aged 50 years and older. METHODS: 180 participants (mean age 61 ± 6 years) were randomized to 24 weeks of exercise plus nutrition supplementation or no intervention. The primary outcome was gait speed, with additional physical and cognitive function measures, self-rated health, and health-related quality of life as secondary outcomes. Information collected also included dietary intake by 3-day dietary records, and blood sampling for renal function, glycated hemoglobin, serum vitamin B12, 25-hydroxyvitamin D, and biochemical indices of bone turnover. RESULTS: There was no significant group difference in the change of gait speed, muscle strength, muscle power, cardiovascular fitness, or cognitive function over time, either by intention-to-treat or per-protocol analysis. A significant time × group effect (P = .039) on self-rated health was detected, but there was no significant time or time × group difference in the change of physical and mental health-related quality of life measures over time. In addition, moderate physical activity level was greatly increased from baseline to 24 weeks in the intervention group compared with the control group. CONCLUSIONS AND IMPLICATIONS: A 24-week exercise and nutrition supplementation program among community-living people in late midlife to early old age improved self-rated health and the overall level of physical activity, without objective improvements in physical and cognitive function.

Effects of exercise and nutrition supplementation in community-dwelling older Chinese people with sarcopenia: a randomized controlled trial.

BACKGROUND: Limited trials examining the effect of exercise and nutrition supplementation in older people with sarcopenia are available. OBJECTIVES: to assess the impact of resistance exercise program targeting muscle strength and power with and without nutrition supplementation on gait speed, body composition, physical function and quality of life. METHODS: this trial randomized 113 community-dwelling older Chinese adults aged ≥65 and with sarcopenia defined using the Asian Criteria into one of the three groups: exercise program alone, combined-exercise program and nutrition supplement or waitlist control. The exercise program consisted of 90-min group training twice weekly and one-home session weekly for 12 weeks. Participants in the combined group were additionally asked to consume nutrition supplement twice daily for 12 weeks. Both groups were encouraged to keep home exercise after intervention period for another 12 weeks to detect sustained effect. The primary outcome was gait speed. RESULTS: at 12 and 24 weeks, gait speed did not differ significantly between groups. Significant improvement in leg extension, and five-chair stand test occurred in both intervention groups that persisted to 24 weeks. Physical Activity Scale for the Elderly improved in both intervention groups that persisted until 24 weeks only in the combined group. Lower limb muscle and appendicular skeletal muscle mass increased significantly in the combined group but the increase was not sustained to 24 weeks. CONCLUSION: the exercise program with and without nutrition supplementation had no significant effect on the primary outcome of gait speed but improved the secondary outcomes of strength and the five-chair stand test in community-dwelling Chinese sarcopenic older adults. CLINICALTRIALS.GOV IDENTIFIER: NCT02374268.

A randomized controlled trial to investigate the impact of a low glycemic index (GI) diet on body mass index in obese adolescents.

BACKGROUND: The role of a low glycemic index (GI) diet in the management of adolescent obesity remains controversial. In this study, we aim to evaluate the impact of low GI diet versus a conventional Chinese diet on the body mass index (BMI) and other obesity indices of obese adolescents. METHODS: Obese adolescents aged 15-18 years were identified from population-recruited, territory-wide surveys. Obesity was defined as BMI ≥95th percentile of Hong Kong local age- and sex-specific references. Eligible subjects were randomized to either an intervention with low GI diet (consisting of 45-50% carbohydrate, 30-35% fat and 15-20% protein) or conventional Chinese diet as control (consisting of 55-60% carbohydrate, 25-30% fat and 10-15% protein). We used random intercept mixed effects model to compare the differential changes across the time points from baseline to month 6 between the 2 groups. RESULTS: 104 obese adolescents were recruited (52 in low GI group and 52 in control group; 43.3% boys). Mean age was 16.7 ± 1.0 years and 16.8 ±1.0 years in low GI and control group respectively. 58.7% subjects completed the study at 6 months (65.4% in low GI group and 51.9% in control group). After adjustment for age and sex, subjects in the low GI group had a significantly greater reduction in obesity indices including BMI, body weight and waist circumference (WC) compared to subjects in the control group (all p <0.05). After further adjustment for physical activity levels, WC was found to be significantly lower in the low GI group compared to the conventional group (p = 0.018). CONCLUSION: Low GI diet in the context of a comprehensive lifestyle modification program may be an alternative to conventional diet in the management of obese adolescents. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Ref. No: NCT01278563.

A prospective cohort study examining the associations of dietary calcium intake with all-cause and cardiovascular mortality in older Chinese community-dwelling people.

BACKGROUND: Most epidemiological studies of calcium intake and mortality risk have been conducted in populations with moderate to high calcium intake, and limited studies have focused on populations with low habitual calcium intake (i.e., mean dietary calcium intake <700 mg/d). OBJECTIVE: This study investigated the association between dietary calcium intake and death from all causes and cardiovascular disease in Chinese population with low habitual calcium intake. DESIGN: Data from 3,139 Chinese men and women in a population-based prospective cohort study, aged >=65 years and free of heart diseases or stroke at baseline, were analyzed. Primary outcome measures, identified from the death registry, were death from all causes and cardiovascular disease. Dietary calcium intake assessed using a validated food frequency questionnaire was categorized into sex-specific quartiles. Data on use of supplemental calcium (yes or no) including individual calcium supplements and other calcium containing supplement were collected. Cox regression models adjusted for demographic and lifestyle variables were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI). RESULTS: During a median of 9.1 years of follow-up, 529 all-cause deaths (344 men, 185 women) and 114 (74 men, 40 women) deaths from cardiovascular disease were identified. An inverse trend between dietary calcium intake and mortality was observed. Compared with the lowest quartile (<458 mg/d for men, <417 mg/d for women), the highest quartile of dietary calcium intake (>762 mg/d for men, >688 mg/d for women) had a significantly reduced risk of all-cause mortality (multivariate HR=0.63, 95% CI=0.49-0.81, P(trend)<0.001) but an insignificant decreased risk of cardiovascular mortality (multivariate HR=0.70, 95% CI=0.41-1.21, P(trend)=0.228). Similar inverse association was observed when the analyses were stratified on calcium supplemental use. CONCLUSIONS: Higher intake of dietary calcium was associated with reduced risk of all-cause mortality and possibly cardiovascular mortality in Chinese older people with low habitual calcium intake.

Not all elderly people benefit from vitamin D supplementation with respect to physical function: results from the Osteoporotic Fractures in Men Study, Hong Kong.

OBJECTIVES: To examine vitamin D status and its association with physical performance and muscle mass in older Chinese men. DESIGN: Cross-sectional and prospective cohort study design. SETTING: Hong Kong, People's of Republic of China. PARTICIPANTS: Nine hundred thirty-nine community-dwelling men aged 65 and older for cross-sectional analysis and 714 for longitudinal analysis. MEASUREMENTS: Baseline serum 25-hydroxyvitamin D (25OHD) was measured using a competitive radioimmunoassay kit. Baseline and 4-year physical performance measures (grip strength, 6-m walking speed, step length in a 6-m walk, time to complete five chair stands) were measured, and appendicular skeletal muscle mass (ASM) was assessed using dual-energy X-ray absorptiometry. Data were collected for confounding factors: demographic, number of diseases, smoking, alcohol use, body mass index, physical activity, diet, season of blood sampling, and serum parathyroid hormone (PTH) level. Multivariate regression analyses were performed with adjustments for confounding factors. RESULTS: Mean ± standard deviation serum 25OHD level of this sample of Chinese community-dwelling older men who had a high level of baseline physical function was 77.9 ± 20.5 nmol/L; 94.1% of participants had serum 25OHD levels of 50 nmol/L or greater. Median (interquartile range) serum PTH level was 4.1 pmol/L (3.1-5.5 pmol/L). After adjustment for potential confounding factors, serum 25OHD levels were not associated with baseline or 4-year change in physical performance measures and ASM. CONCLUSION: In Chinese older men who are vitamin D replete and have a high level of baseline physical function, vitamin D may not have an important role in physical function and muscle mass.

Chinese tea consumption is associated with longer telomere length in elderly Chinese men.

Environmental and lifestyle factors that affect oxidative stress and inflammation may influence telomere length (TL). There are limited data to relate the effect of dietary components on TL. The present study examined the association between food groups and TL in a sample of elderly Chinese. In a sample of 2006 Chinese (976 men and 1030 women) aged 65 years and over, TL was measured by quantitative real-time PCR and daily intake of food groups was assessed by a validated FFQ. Linear regression and analysis of covariance were used to examine the association between food group intake and TL, with adjustment for demographic and lifestyle factors. In men, only Chinese tea consumption was significantly associated with TL after adjustment for demographics and lifestyle factors (P = 0.002). Mean difference in TL for those in the highest quartile of Chinese tea consumption (>3 cups/d or >750 ml/d) as compared with those in the lowest quartile of Chinese tea consumption (

Effects of lifestyle and diet on bone health in young adult Chinese women living in Hong Kong and Beijing.

BACKGROUND: Dietary and lifestyle variations may be too small to detect possible associations with bone mineral density (BMD) within a community. Pooled data from communities with different diets and lifestyle but of the same ethnicity may help explore these associations. OBJECTIVE: To examine the effects of dietary and lifestyle factors on BMD in young Chinese women. METHODS: Baseline data were analyzed from 441 women aged 20 to 35 years in Hong Kong and Beijing who were participating in a longitudinal study evaluating the effect of milk supplementation on bone health. Data on demographic characteristics, lifestyle, use of oral contraceptives, diet, physical activity, and BMD of total hip, femoral neck, and total spine measured by dual-energy x-ray absorptiometry were pooled for analysis. RESULTS: Hong Kong subjects had significantly lower BMD and higher body-size-adjusted dietary intakes of protein, fat, fiber, vitamins, potassium, sodium, and selenium than Beijing subjects. Multivariate regression of pooled data showed that body mass index was the most important determinant of BMD at all sites. Age was negatively associated and use of oral contraceptives was positively associated with femoral neck BMD. Carbohydrate intake was positively associated with total hip BMD. Fiber intake was negatively associated with BMD at total hip and total spine. Increased vitamin E intake was associated with greater total spine BMD. None of the nutrients were associated with BMD at the femoral neck. CONCLUSIONS: Diet, lifestyle, and BMD differed greatly between young women from Hong Kong and Beijing. Body mass index was the most important determinant of BMD in young Chinese women, whereas age, use of oral contraceptives, and diet had less pronounced effects.