High-intensity interval training prevents muscle mass loss in overweight Chilean young adults during a hypocaloric-Mediterranean diet: a randomized trial

The hypocaloric Mediterranean diet (MD) mainly reduces fat mass but inevitably causes a loss of skeletal muscle mass. High-intensity interval training (HIIT) seems to have advantages in preserving muscle mass during a hypocaloric regime. Our study compares body composition and metabolic changes in overweight and obese Chilean women and men after 3 months of weight loss treatment with a Mediterranean-type hypocaloric diet, HIIT, or a combination of both. The study included 83 overweight or obese women and men between the ages of 25 and 50. The subjects were randomly assigned to one of the three intervention groups: (1) MD, (2) EX, and (3) MD + EX. Baseline and post-intervention measurements included: (a) body composition by dual-beam densitometry, muscle, and fat measurements by thigh ultrasound and computed tomography; (b) handgrip and quadriceps muscle strength; (c) exercise performance by peak oxygen consumption, peak load, work efficiency, and exercise energy expenditure; and (d) metabolic parameters. Out of 83 participants, the retention rate was 49% due to low compliance with the interventions. As expected, the MD group resulted in significantly greater weight loss (MD -7%, EX -0.6% and MD + EX -5.3%) and appendicular fat mass loss (MD -11.1%, EX -2.9, MD + EX -10.2%) but was associated with significant lean tissue loss (2.8%), which was prevented by HIIT (EX -0.1 and MD + EX -0.6%). Metabolic and glycoxidative parameters remained unchanged, irrespective of changes in body composition. Hypocaloric diets remain the most effective means to lose weight and body fat. However, it induces a loss of lean body mass when not accompanied by exercise training. This study shows that HIIT prevents the loss of muscle mass caused by a hypocaloric Mediterranean diet.

FACTORS RELATED TO TOTAL ENERGY EXPENDITURE IN OLDER ADULTS (CHILE)

AIM

to asses Total Energy Expenditure (TEE) in healthy Chilean institutionalized or independently older people Methods: twenty seven young (27-30 years), 27 institutionalized (> 65 years old) and 27 free-living older (> 65 years old) participants were studied. Body composition was estimated by dual energy X-ray absorptiometry. Physical activity energy expenditure (AEE) and TEE were assessed using Actiheart accelerometers. The Mini Nutritional Assessment (MNA) was applied and Timed Up and Go (TUG) was measured.

RESULTS

AEE was 171, 320 and 497 kcal/day in institutionalized, free living older and young participants, respectively (p < 0.01 between young and older participants). Both absolute TEE and TEE/RMR was higher in young people. Multiple regression analysis accepted age, MNA and TUG as significant predictors of AEE (r2 = 0.24 p < 0.01).

CONCLUSION

AEE and PAL were lower among older people, with no differences by institutionalization.

Dietary advanced glycation end products and their role in health and disease

Over the past 2 decades there has been increasing evidence supporting an important contribution from food-derived advanced glycation end products (AGEs) to the body pool of AGEs and therefore increased oxidative stress and inflammation, processes that play a major role in the causation of chronic diseases. A 3-d symposium (1st Latin American Symposium of AGEs) to discuss this subject took place in Guanajuato, Mexico, on 1-3 October 2014 with the participation of researchers from several countries. This review is a summary of the different presentations and subjects discussed, and it is divided into 4 sections. The first section deals with current general knowledge about AGEs. The second section dwells on mechanisms of action of AGEs, with special emphasis on the receptor for advanced glycation end products and the potential role of AGEs in neurodegenerative diseases. The third section discusses different approaches to decrease the AGE burden. The last section discusses current methodologic problems with measurement of AGEs in different samples. The subject under discussion is complex and extensive and cannot be completely covered in a short review. Therefore, some areas of interest have been left out because of space. However, we hope this review illustrates currently known facts about dietary AGEs as well as pointing out areas that require further research.

Folates Induce Colorectal Carcinoma HT29 Cell Line Proliferation Through Notch1 Signaling

Folic acid (FA) consumption at high levels has been associated with colon cancer risk. Several mechanisms have been proposed to explain this association. The Notch signal pathway has been implicated in the regulation of cellular proliferation. Our aim was to demonstrate that high concentrations of FA or its reduced form, 5-methyltetrahydrofolic acid (5-MTHF), increase colorectal carcinoma HT29 cell proliferation through an increase of Notch1 activation and to prove if the inhibition of Notch1 activation by gamma secretase inhibitor, reduce the effect of folic acid. HT29 cells were cultured in high (400 nM), low (20 nM), or 0 nM FA or 5-MTHF concentrations during 96 h with or without DAPT (gamma secretase inhibitor). Cell proliferation was determined by the methylthiazole tetrazolium method, and Notch1-intracellular domain (NICD) was analyzed by flow cytometry. HT29 cells exposed to 400 nM FA or 5-MTHF showed higher proliferation rate than those exposed to 20 nM of FA or 5-MTHF (P < 0.01) during 96 h. NICD expression increased at higher FA or 5-MTHF concentrations compared with lower concentrations (P < 0.01). This effect on proliferation was partially reversible when we blocked Notch1 activation with the inhibitor of γ-secretase (P < 0.05).These data suggest that high concentration of FA and 5-MTHF induce HT29 cell proliferation activating Notch1 pathway.

Variability of formulas to assess insulin sensitivity and their association with the Matsuda index

OBJECTIVE

To assess the individual variability of HOMA and QUICKI indexes for the assessment of insulin resistance, using three fasting blood samples obtained within 30 minutes.

RESEARCH METHODS & PROCEDURES

Data from 80 participants aged 41.5 ± 15 years (26 females), who underwent an oral glucose tolerance test to calculate Matsuda index, were used. Every participant had three fasting blood samples obtained within 30 minutes and four blood samples obtained at 30, 60, 90 and 120 minutes after a 75 g oral glucose load. Insulin and glucose were measured in each sample. HOMA and QUICKI indexes were calculated using the nine possible combinations of the three fasting blood samples. Matsuda index was calculated with all samples obtained.

RESULTS

Median values of HOMA-IR, HOMA-β, QUICKI and Matsuda indexes were 1.9, 117.9, 0.35 and 3.71 arbitrary units, respectively. The individual variation coefficients of HOMA-IR, HOMA-β and QUICKI were 11.8 (7.8-18.9), 15 (10.2-22.9) and 1.8 (8.8-21.9) % respectively. When compared with Matsuda index, the R squared values of HOMA-IR, HOMA-β and QUICKI were 0.46, 0.2 and 0.71, respectively.

CONCLUSIONS

Among fasting indexes for insulin resistance, QUICKI had the lower variation coefficient and the higher correlation with Matsuda index.

Central obesity and not age increases skeletal muscle lipids, without influencing lean body mass and strength

BACKGROUND/AIMS

To measure skeletal muscle lipid infiltration, its association with insulin resistance (IR) lean mass and function, in Chilean men differing in age and body composition. Our hypothesis was that muscle lipid accumulation would be higher among older and heavier individuals and this would deteriorate insulin sensitivity (IS) and decrease muscle mass and function, both features of the ageing process.

METHODS

Healthy men (38 < 55 and 18 > 65 years), underwent anthropometric measurements, body composition assessment through radiologic densitometry, Nuclear Magnetic Resonance spectroscopy at the tibialis anterioris muscle to measure intra (IMCL) and extramyocellular lipids (EMCL), quadriceps and handgrip strength, 12 minute walking distance and serum biochemistry (haemoglobin, lipoproteins, creatinine, ultrasensitive C Reactive Protein, fasting and post glucose insulin and glucose concentrations, to assess IS). Physical activity was estimated by actigraphy.

RESULTS

23 men were eutrophic, 26 were overweight and 7 were obese and mostly sedentary, independent of age. Both IMCL and EMCL were higher in overweight/ obese men. Abdominal fat was negatively associated with IS and positively correlated with muscle lipid accretion (both IMCL and EMCL), but not with age. As expected, older individuals had lower muscle mass and strength, but not more adipose tissue nor intramyocellular lipids, yet were more glucose intolerant.

CONCLUSIONS

central obesity was associated with IMCL and EMCL infiltration and IR. This type of lipid accretion was not related with ageing nor age-related sarcopenia. Older individuals were more glucose intolerant, which was explained by a decrease of insulin secretion more than adiposity-related IR.

Bariatric surgery decreases carotid intima-media thickness in obese subjects

BACKGROUND

Obesity has long been associated with an increased risk of cardiovascular disease (CVD). The aim of this study was to evaluate the impact of substantial weight loss induced by bariatric surgery on carotid intima media thickness (C-IMT) (surrogate marker of early atherosclerosis) and classic factors of cardiovascular risk (CVRFs).

METHODS

thirty-one obesity patients were evaluated for bariatric surgery. Twenty-seven were undergone surgery, 14 Roux-en-Y gastric bypass surgery (GBS) and 13 sleeve gastrectomy. The four obese patients who did not undergo surgery, were performed the same evaluations.

MEASUREMENTS

Body weight, BMI, blood pressure, total cholesterol, TC levels, LDL-C, HDL-C, TG, fasting plasma glucose and insulin, HOMA IR, and US B-mode C-IMT was measured.

RESULTS

After 354 ± 92 days follow up, 27 patients that underwent bariatric surgery evidenced a mean body mass index decrease from 38 to 27 k/m² (p < 0.001), simultaneously was observed improvement in CVRFs, 10 years Framingham risk and a significant reduction of therapeutic requirements. C-IMT diminished from a mean of 0.58 ± 0.14 mm to 0.49 ± 0.09 mm (p = 0.0001). Four patients that did not undergo surgery increased C-IMT from 0.52 ± 0.12 to 0.58 ± 0.13 mm (p = 0.03) with no significant changes in CVRFs.

CONCLUSION

Weight loss, one year after bariatric surgery, GBS and sleeve gastrectomy, decreases C-IMT; improve CVRFs and 10 years Framingham risk.

Variability of glycemic and insulin response to a standard meal, within and between healthy subjects

AIM

To test the variability within and between subject of glycemic response test following the ingestion of a standard food.

MATERIAL AND METHODS

Glucose and insulin response of a standard meal (white bread) was performed in ten healthy volunteers and repeated under identical conditions for 6 times. Blood glucose and insulin levels were measured in the fasted state and over the 180 min following commencement of consumption of the foods The Area Under the Curve (AUC) for glucose and insulin was calculated for the values above baseline for the 3-hour period following the standard meal. Within and between coefficient of variation was calculated.

RESULTS

The total intra-individual variation of the gAUC was 51.8% range 24.9 to 91.4%. The inter-individual variation of the gAUC in the complete study was 75.2% . The total intra-individual variation of the iAUC was 51.9%. ranged: 7.7 to 103%. The inter-individual variation in the complete study was 86%.

CONCLUSION

Glucose and insulin response to a reference food has low reliability, therefore limits its clinical utility for individual dietary prescription.

Carotid ultrasound examination as an aging and disability marker

AIM

To explore the usefulness of carotid ultrasound examination as a marker of aging and predictor of disability among older people.

METHODS

Carotid ultrasound, measuring carotid intima media thickness (CIMT) and recording the presence of plaques, was carried out in 152 adults aged 29-59 years (47 women) and in 107 older adults aged 61-88 years (86 women). In all, clinical routine laboratory parameters and lymphocyte telomere length as T/S ratio were measured. Among older adults, 12-min walk, timed up and go, hand grip and quadriceps strength were determined.

RESULTS

CIMT was significantly higher among older people and T/S ratio was significantly higher in young women. Carotid plaques were found in one adult and 17 older people. A multiple regression analysis accepted age, systolic blood pressure and T/S ratios as independent predictors of CIMT (R(2) = 0.51). Among older people, a logistic regression accepted age and the presence of carotid plaques as significant predictors of a 12-min walk speed below 1 m/s.

CONCLUSIONS

An abnormal 12-min walk as an indicator of functional decline among older people is associated with the presence of carotid artery plaques. CIMT is independently associated with age.

Natural killer cell cytotoxicity is not regulated by folic acid in vitro

OBJECTIVES

Folate supplementation may be associated with an increased risk of developing several types of cancer and a derangement of immune function. Among the latter, Natural killer (NK) cells are involved in non-MHC-restricted natural immunity against malignant target cells. Abnormalities in NK cell number or function have been associated with a higher cancer risk. The aim of this study was to study in vitro the possible effect of different concentrations of 5-methyltetrahydrofolic acid (5-MTHF) or folic acid on NK cell cytotoxic function, and expression of the stimulatory and inhibitory receptors KIRDL4, KIRDL3, and NKG2D.

METHODS

Volunteer-derived peripheral mononuclear cells (PBMC) and highly enriched NK cells (95% CD56+ CD16+) were grown in folic acid free-RPMI 1640, supplemented either with folic acid or 5-MTHF (15-100 nM) during 72 h to 96 h.

RESULTS

No differences in the cytolytic activity of PBMC and enriched NK cells were observed. After 96 h of in vitro culture without folate or supplemented with FA or 5-MTHF (30 or 100 nM), there were no changes in the percentage of HPNK receptor-positive cells.

CONCLUSIONS

Our data indicate that a high dose of 5-MTHF or folic acid does not influence NK cell function in vitro.

[Metabolic syndrome prevalence in Chilean children and adolescent with family history of chronic noncommunicable diseases]

Family history (FH+) of non transmisible chronic diseases (NTCD) increase MetS risk. In Chile, the MetS affects 27% of overweight children, and fasting hyperglycemia is very low prevalent (4,0%). The objective was to study the prevalence of MetS and the cardiovascular risk factors (CVRF) in overweight children with a family background of NTCD and analyze its association with the number of relatives witth NTCD and with parental history (PH). In 183 overweight children (BMI > or = p85) mean age 11,8 +/- 1,8 (86 males) with a FH+ (parental or grandparental) of NTCD, were assessed the BMI z (CDC / NCHS), waist circumference, blood arterial pressure, fasting Glucose and Insulin (RIA), triglycerides, HDL chol. The MetS and the CVRF were diagnosed using the Cook phenotype and the insulin resistance (IR) through the HOMA-IR. Chi2, ANOVA, t Student and Willcoxon test were performed. The frequency of FH+ of DM2, hypertension and dyslipidemia were 81,4%, 88,0% and 71,6 % respectively. The MeTS prevalence was 46,5 % associated to overweight magnitude an parental history of NTCD. The prevalence of hypertriglyceridemia was 54,6%, while fasting hyperglycemia affected 31,4% of the sample. There was no association between number of relatives with NTCD and CV risk profile. We conclude that in overweight children with FH+ of NTCD, the prevalence of MetS, dyslipidemia and fasting hyperglycemia are significantly higher, than those observed in the general population of obese children.

[Nutritional status, body composition and bone mineral density in gastric bypass females: impact of socioeconomic level]

BACKGROUND

Roux-en-Y gastric bypass (RYGBP) has had a posilive impact on co-mobidities associated with obesity. However, in the long-term it can induce micronutrient deficiencies.

AIM

To petform a complete nutritional assessment in a group of women previously operated of RYGBP from different socioeconomic levels (SEL).

PATIENTS AND METHODS

Thirtyy three women (19 high SEL and 14 low SEL), were assessed by dietary recalls, anthropometric measurements, muscle strength, bone mineral density, routine clinical laboratory, semm leeds of vitamin B12, 25OH-vitamin D, folate, calcium, ferritine ceruloplasmin and indicators of bone tutnoter (paratbohormone, osteocalcin and urinary pyridinolines). Their values were compared to those of 30 control women (18 high SEL and 12 low SEL).

RESULTS

Low SEL operated women consumed fewer vitamin and mineral supplements compared with their high SEL pairs. No cases of vitamin B12, folic acid or copper deficiencies were detected. Frequency of iron deficiency was similar in patients and controls. Vitamin D insufficiency was higher among patients than in controls (p = 0.047), regardless SEL. Patients had also a higher frequency of high senum P771 and osteocakin and urinary pyridinoline levels. However, no differences in bone mineral density were obseived between operated women and controls.

CONCLUSIONS

Vitamin and mineral deficiencies were lower than expected among operated women. However problems associated with vitamin D deficiency were highly prevalent among patients operated of RYGBP, irrespective SEL. These alterations were only detectable through specific markers at this stage, because they did not translate into lower bone mineral density (BMD) of sutgical patients, probably due to the higher pre-operative BMD of these moibid obese patients

Effects of enalapril or nifedipine on muscle strength or functional capacity in elderly subjects. A double blind trial

INTRODUCTION

The inhibition of angiotensin-converting enzyme could be useful to avoid sarcopenia in the elderly.

MATERIALS AND METHODS

We compared in a prospective double blind trial, the effects of treatment with enalapril or nifedipine on muscle performance in hypertensive elderly subjects. Patients were followed for nine months, and at baseline, 4.5 months and the end of follow-up, quadriceps and hand grip muscle strength, walking capacity, timed up and go and the short physical performance test were measured.

RESULTS

During follow-up, more subjects on nifedipine than on enalapril discontinued the medication due to side-effects. No differences in the evolution of muscle strength, walking capacity or functional measures were observed. At nine months, plasma angiotensin-converting enzyme activity decreased by 6.0+/-2.5 U/L among patients on enalapril and increased by 8.5+/-4.2 U/L (p<0.001) among patients on nifedipine.

CONCLUSION

In this group of elderly subjects, enalapril was not superior to nifedipine with regard to the age-related decline of muscle performance.

[Statement about the medical and surgical treatment of overweight and obesity]

This is an updated review of the available treatments for obesity, which can be used when lifestyles modifications fail. Using the available information and the experience of the members of this advisory group, a recommendation is given about the most useful treatments, according to the severity of obesity and its complications. With regards to pharmacological treatments, only sibutramine and orlistat are approved on a worldwide basis for the treatment of obesity. These medications achieve a 10% higher weight reduction than lifestyles modification. A third medication, rimonobant, is also more effective than lifestyles modifications, but it was withdrawn due to psychological safety issues. The indications for surgical treatment and a brief description of the available techniques, success rates and complications are outlined. Finally, the need to have followed up protocols for patients and the formation of multidisciplinary treatment teams is underscored.

[Statement about diagnosis assessment ano non pharmacological treatment of obesity]

The risk of complications of obesity is proportional to body mass index and is higher in severe or morbid obesities and when abdominal or visceral fat is predominant. In Chile the prevalence of obesity is increasing. According to the World Health Organization, obese subjects must reduce at least a 5% of their weight to reduce the risk of complications. Although this amount of reduction is seldom achieved with non pharmacological treatments, better results are obtained with multidisciplinary/ approaches that include a medical, psychosocial and laboratory assessment, to determine obesity level and different factors involved and the associated complications. In a second stage, goals of treatment are set and a personalized treatment is designed including dietary changes and physical activity. The aim is to obtain perdurable lifestyles modifications.

[Effect of probiotic Saccharomyces boulardii on prevention of antibiotic-associated diarrhea in adult outpatients with amoxicillin treatment]

BACKGROUND

Antibiotic-associated diarrhea is one of the most common adverse effects of antimicrobials. Any antimicrobial can potentially produce diarrhea but beta-lactamics have a higher risk. Among these, amoxicillin is widely indicated in ambulatory practice. One of the alternatives suggested to prevent antibiotic-associated diarrhea, is the use of the probiotic Saccharomyces boulardii.

AIM

To evaluate whether the concomitant use of Saccharomyces boulardii and amoxicillin can prevent antibiotic associated diarrhea in ambulatory adults with acute infections diseases, without provoking other adverse effects.

MATERIAL AND METHODS

Eighty six adults (aged 15 to 81 years) with acute infectious diseases, excluding those arising in the gastrointestinal tract, that received a prescription of oral amoxicillin for 5 to 10 days, were included. In a controlled randomized, double blind trial, 41 patients were assigned to receive lyophilized Saccharomyces boulardii (500 mg/day) during 12 days, and 45 patients were assigned to placebo for the same period.

RESULTS

Ten percent of patients (9/86) reported acute diarrhea, 9,8% (4/41) in the experimental group and 11.196 (5/45) in the control group (p = 100). No adverse effects were associated to the use of the probiotic.

CONCLUSIONS

Saccharomyces boulardii (500 mg/day) did not prevent diarrhea related to amoxicillin.

Methylation status in healthy subjects with normal and high serum folate concentration

OBJECTIVE

We assessed the impact of high serum folate concentration on erythrocyte S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH) concentrations, SAM/SAH ratio, CpG methylation levels across the promoter region of the extracellular superoxide dismutase (ec-SOD) gene, and ec-SOD activity in healthy men.

METHODS

Serum folate levels were measured in 111 subjects who were categorized in quintiles according to their folate status. Subjects located at the lowest, middle, and upper quintiles were selected for assessment of SAM and SAH by high-performance liquid chromatography, C677T genotype of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, ec-SOD methylation of CpG sites in lymphocytes genomic DNA by bisulfate treatment, and ec-SOD activity by a chemical assay.

RESULTS

Sixteen subjects were in the lowest serum folate quintile (<23.6 nmol/L), 17 in the middle (>34-<42 nmol/L), and 14 in the highest (>45nmol/L). SAM concentration was higher in the upper than in the middle and lowest quintiles (5.57 +/- 1.58, 2.52 +/- 0.97, 2.29 +/- 1.2 micromol/L; P < 0.0001). SAH concentration was higher in the upper compared with the lowest quintile (0.76 +/- 0.24 versus 0.52 +/- 0.23 micromol/L, P < 0.001). There were no differences in the SAM/SAH ratio, ec-SOD activity, methylation status of CpG sites of the ec-SOD gene, and TMTHFR C677T genotype between groups.

CONCLUSION

Serum folate concentrations in the highest quintile among healthy humans are associated with increased erythrocyte SAM and SAH concentrations, but not with SAM/SAH ratio or with methylation levels of CpG sites across the promoter region of the ec-SOD gene. Further research is required to determine if these findings are beneficial or harmful.

Assessment of sarcopenia: longitudinal versus cross sectional body composition data

BACKGROUND AND AIMS

An accurate diagnosis of sarcopenia is required. The aim of this study is to correlate the results of two methods to define sarcopenia using cross sectional body composition data, with actual loss of fat free mass.

METHODS

Healthy older subjects (926 females and 381 males aged 70 years or more) and healthy young adults (425 females and 151 males aged 20 to 40 years) were studied. Body composition was assessed by double beam X ray absorptiometry (DEXA). Among older subjects, a contemporary subsample of 148 females and 45 males had two or more measurements, separated by 4.8+/-1.5 years and loss of fat free mass per year was calculated. In the whole sample, total and appendicular lean body mass index were calculated as total or appendicular lean body mass/height. Using data from young people, sex specific t scores were obtained. In older subjects residuals were derived from a regression equation, using total or appendicular fat free mass as the dependent variable and height, fat free mass and age as independent variables.

RESULTS

The concordance between residuals and t scores to define sarcopenia was 68 and 72%, respectively. Among subjects with two or more measurements, men and women lost a mean of 521+/-454 and 221+/-399 g/year of fat free mass, respectively. The odds ratio of losing more than 822 g lean body mass /year among men or 514 g lean body mass /year among women was 2.63 and 2.64 for subjects classified in the two lowest quintiles of sarcopenia, using t scores or residuals, respectively.

CONCLUSIONS

Cross sectional body composition data can predict loss of fat free mass among older people.

Effects of vitamin D supplementation and exercise training on physical performance in Chilean vitamin D deficient elderly subjects

The aim was to assess the effects of resistance training and vitamin D supplementation on physical performance of healthy elderly subjects. Ninety-six subjects, aged 70 years or more with 25 OH vitamin D levels of 16 ng/ml or less, were randomized to a resistance training or control group. Trained and control groups were further randomized to receive in a double blind fashion, vitamin D 400 IU plus 800 mg of calcium per day or calcium alone. Subjects were followed for nine months. Serum 25 OH vitamin D increased from 12.4+/-2.2 to 25.8+/-6.5 ng/ml among subjects supplemented with vitamin D. Trained subjects had significant improvements in quadriceps muscle strength, the short physical performance test and timed up and go. The latter improved more in trained subjects supplemented with vitamin D. At the end of the follow up, gait speed was higher among subjects supplemented with vitamin (whether trained or not) than in non-supplemented subjects (838+/-147 and 768+/-127 m/12 min, respectively, p=0.02). Romberg ratio was lower among supplemented controls than non-supplemented trained subjects (128+/-40% and 144+/-37%, respectively, p=0.05). In conclusion, vitamin D supplementation improved gait speed and body sway, and training improved muscle strength.

Effect of a Nutritional Supplementation on Bone Health in Chilean Elderly Subjects with Femoral Osteoporosis

OBJECTIVE

To study the effects of a special nutritional supplement on bone mineral density and bone turnover markers in Chilean elderly subjects with femoral osteoporosis.

SETTING

Public primary health care clinics in Chile.

SUBJECTS

Free living elderly subjects with femoral osteoporosis.

INTERVENTIONS

Subjects were randomized to receive the usual nutritional supplement provided by the Chilean Ministry of Health or a special nutritional supplement providing, among other nutrients, 90 mg isoflavones, 800 mg calcium, 400 IU vitamin D, 60 ug vitamin K and 31 g proteins per day.

MEASURES OF OUTCOME

At baseline, and after six and twelve months of supplementation, body composition, bone mineral density, serum 25 OH vitamin D, intact parathyroid hormone (iPTH), osteocalcin, decarboxylated osteocalcin, urinary aminoterminal telopeptide of type I collagen (NTX), deoxypyridoline cross links (Dpd) and equol were measured. Every month, urinary daidzein was measured in a morning urine sample.

RESULTS

No differences between treatment groups were observed in body composition or bone mineral density changes. The group receiving the special supplement had a significant increase in serum 25 OH vitamin D and a significant decrease in serum iPTH and decarboxylated osteocalcin. No association between daidzein or equol excretion and changes in bone mineralization was observed.

CONCLUSIONS

A special supplement delivered to elderly subjects with osteoporosis improved serum vitamin D and reduced serum iPTH and undercarboxylated osteocalcin levels but did not affect BMD.

Effects of a nutritional supplement on the immune response and cytokine production in free-living Chilean elderly

BACKGROUND

Immune response is impaired in the elderly. Our aim was to study the effects of a special nutritional formula on the immune response and response to influenza and pneumococcal vaccination in elderly subjects.

METHODS

Sixty healthy subjects aged > or = 70 years, with a Mini Mental score > or = 22 were studied. Half of the subjects received a special nutritional formula (in addition to the regular diet) providing, among other nutrients, 480 kcal, 31 g proteins, 120 IU vitamin E, 3.8 microg vitamin B12, 400 microg folic acid, 10(9) cfu Lactobacillus paracasei (NCC 2461), and 6 g of fructo-oligosaccharides. At 4 months of follow-up, subjects were vaccinated against influenza and pneumococcus. Lymphokine production by mononuclear cells (PBMC), lymphocyte subpopulations, and natural killer cell (NK) activity were measured at baseline and 4 months of follow-up (before vaccination). Antibodies against influenza and pneumococcal antigens and flu-stimulated production of interferon gamma and interleukin-2 by PBMC were measured at 4 and 6 months. Skin response to 7 recall antigens and body composition were assessed at baseline and at 4 and 12 months. All infections occurring during the study period were recorded.

RESULTS

NK activity increased in supplemented subjects and decreased in nonsupplemented individuals. Interleukin-2 production by PBMC and the proportion of T cells with NK activity decreased in controls and did not change in supplemented subjects. Supplemented subjects reported less infections than nonsupplemented individuals (in 13% and 22% of scheduled visits, respectively; p = .02).

CONCLUSIONS

This nutritional supplement increased innate immunity and protection against infections in elderly people.

A high body mass index protects against femoral neck osteoporosis in healthy elderly subjects

OBJECTIVE

In a large sample of elderly subjects, we assessed the possible protective effect of obesity on the development of osteoporosis.

METHODS

Healthy subjects 70 y or older and of low socioeconomic level were studied. Bone mineral density was measured in the femoral neck by using a Lunar Prodigy double beam densitometer and compared measurements with appropriate standards. Osteoporosis was defined according to criteria of the World Health Organization (WHO). Body weight and height were recorded simultaneously, and body mass index (BMI) was calculated as weight (kg) divided by height (m2). Age-adjusted odds ratios for femoral osteoporosis were calculated for WHO-proposed BMI ranges in women and men, with an odds of one for a BMI below 25 kg/m2.

RESULTS

Eight hundred forty-five subjects (615 women and 230 men; mean age, 75 +/- 4.4 y) were studied. Mean BMI was 28.1 +/- 4.7 kg/m2. Twenty five percent of women and 11% of men had osteoporosis (P < 0.001). Forward stepwise multiple regression analysis showed BMI to be the best independent predictor of bone mineral density in women and men. The age-adjusted odds ratios for femoral osteoporosis were 0.34 (95% confidence interval [CI], 0.21 to 0.55) and 0.13 (95% CI, 0.04 to 0.43) for women and men with a BMI between 25 and 30 kg/m2, respectively. The odds ratios for women and men with a BMI between 30 and 35 kg/m2 were 0.21 (95% CI, 0.11 to 0.39) and 0.09 (95% CI, 0.01 to 0.67), respectively

CONCLUSIONS

This study confirms the protective effect of a high BMI on femoral neck bone mineral density among elderly subjects. The risk for osteoporosis among men and women with a BMI above 30 kg/m2 was approximately 33% compared with subjects with a normal BMI.

Serum folate and homocysteine levels in obese females with non-alcoholic fatty liver

OBJECTIVE

Folate depletion and hyperhomocysteinemia increase the risk for hepatic alcoholic damage and promote oxidative stress in animals. In addition, some investigators have reported an inverse association between serum folate and body mass index and a positive correlation between total homocysteine and fat mass. We investigated whether there is an association between serum folate and total homocysteine concentrations with the presence of non-alcoholic fatty liver disease (NAFLD) in obese subjects.

METHODS

Forty-three obese (body mass index > or =35 kg/m2) patients who underwent bariatric surgery and hepatic biopsy were included. Serum total homocyteine, folate and vitamin B12 concentrations and hepatic enzymes were measured. Liver biopsies were graded for the presence of fat, inflammation, and fibrosis on a scale from 0 to 3. A total histologic score was calculated based on the sum of partial scores. Severe NAFLD was defined as a total score of at least 4 or severe steatosis (partial score for fat = 3).

RESULTS

Severe NAFLD was present in 17 patients. Serum folate concentration was significantly lower in obese patients with NAFLD than in those with normal liver or minimal alterations (9.3 +/- 3.5 versus 12.2 +/- 3.1 ng/mL, P = 0.005). Serum total homocysteine and vitamin B12 concentrations were similar in both groups. An inverse correlation between serum folate concentration and body mass index was observed (r = -0.31, P = 0.046).

CONCLUSIONS

In this study, severe NAFLD in obese subjects was associated with lower serum folate concentrations and serum homocysteine and vitamin B12 concentrations were not associated with liver damage in obese subjects.

Hyperhomocysteinemia in healthy young men and elderly men with normal serum folate concentration is not associated with poor vascular reactivity or oxidative stress

The mechanism by which homocysteine (Hcy) causes endothelial dysfunction is probably mediated by oxidative stress. The aim of this study was to evaluate the effect of oxidative stress on endothelial function in young and elderly hyperhomocysteinemic (HHcy) men. A total of 35 HHcy (Hcy > 15 micro mol/L), young (n = 15; 20-40 y) and elderly men (n = 20; > 65 y) and 33 normohomocysteinemic (NHcy; controls) young (n = 14) and elderly (n = 19) men (Hcy < 13 micro mol/L), without classic cardiovascular risk factors were recruited. Serum Hcy, folate, and vitamin B-12, whole-blood glutathione, plasma total antioxidants status, TBARS, and 8-F(2alpha) isoprostanes were determined. Noninvasive ultrasound measurements of endothelium-dependent (EDVR) and -independent dilatation (EIVR) were performed. EDVR, EIVR, and markers of oxidative stress did not differ among the groups. Folate concentrations were higher in elderly than in young men (P < 0.001), independent of Hcy concentrations. Vitamin B-12 concentrations were lower in HHcy than in NHcy elderly men (P < 0.045). EDVR was correlated with folate concentrations in young men (r = 0.40, P = 0.04) and negatively with BMI in elderly men (r = -0.52, P = 0.002). In the present study, HHcy with normal serum folate concentrations was not associated with poor EDVR or oxidative stress in healthy young and elderly men.

Long-Term Nutritional and Digestive Consequences of Pelvic Radiation

OBJECTIVE

To study long-term changes in nutritional status and gastrointestinal (GI) functions of 15 women previously treated with radiotherapy for gynecological cancer. Two years prior to this research, these patients had been assessed twice: before external radiotherapy and 5 weeks later, at the completion of the external dose (45-50 Gy).

METHODS

Each patient was given complete clinical evaluation, consisting of dietary, physical activity and digestive symptoms questionnaires. Blood was drawn for routine clinical laboratory tests (hemoglobin, white blood cell count, creatinine, lipoproteins, glucose, total proteins, albumin, and C reactive protein). Body composition was assessed by classical anthropometric indicators and double beam X-ray absorptiometry (DEXA), while muscle strength was measured through a hand dynamometer. Resting energy expenditure (REE), obtained by indirect calorimetry, was subtracted from energy ingestion, derived from dietary records, to calculate energy balance.

RESULTS

This third evaluation included fifteen patients. A significant increase in body mass index (BMI), % body fat and waist circumference were observed in comparison to earlier evaluations. The lean compartment decreased significantly, and REE descended in parallel. Meanwhile, total energy, fat and protein intake increased, compared to previous measurements. The changes in bowel habits observed during radiotherapy persisted at this third evaluation, with the exception of diarrhea, which was less reported. Abdominal bloating and rectal symptoms were the most prevalent complaints.

CONCLUSIONS

After radiation treatment for gynecological cancer, patients gained more body fat than expected in Chilean women around menopause. In spite of high protein ingestion, the loss of fat-free mass observed during radiation treatment was not recovered along with weight increase. This is probably associated with infrequent physical activity, both during and after treatment, and hyperphagia.

[Dietary phytoestrogen and its potential benefits in adult human health]

Human diet contains a series of bioactive vegetal compounds that can improve human health. Among these, there has been a special interest for phytoestrogens. This article reviews the evidence about the potential benefits of phytoestrogens for human health. Forty eight manuscripts were selected for their study design and relevance to human health. The cell growth inhibitory effects of phytoestrogens and their implication in breast cancer are reviewed. Also the effects of these compounds on serum lipid levels and the effectiveness of a phytoestrogen derivate, ipriflavone, on the prevention of osteoporosis are analyzed. Although these compounds have a great potential for improving health, there is still not enough evidence to recommend the routine use of phytoestrogens.

Effects of prebiotics on the immune response to vaccination in the elderly

BACKGROUND

Prebiotics stimulate the growth of bifidogenic bacteria in the gut. The aim of this work was to assess the effects of a prebiotic mixture on the immune response in healthy elderly people.

METHODS

Healthy free-living elderly people (age, > or = 70 years), receiving a nutritional supplement that provided 1.6 MJ, 15 g of protein, and 50% of vitamin daily reference values per day, were randomly assigned to receive a prebiotic mixture (6 g/d of a 70% raftilose and 30% raftiline mixture) or placebo (6 g of maltodextrin powder) for 28 weeks. At week 2 of the study, all subjects were vaccinated with influenza and pneumococcal vaccines. At weeks 0, 2, and 8 of the study, serum total proteins, albumin, immunoglobulins, saliva secretory immunoglobulin A (IgA), and serum titers of influenza A and B and pneumococcal antibodies were measured. At week 8, cultured peripheral monocyte cell secretion of interleukin-4, interferon-gamma, and lymphocyte proliferation, stimulated with phytohemagglutinin and influenza antigen, were measured.

RESULTS

Sixty-six subjects were considered eligible for the study, and 43 (20 receiving prebiotics and 23 receiving placebo) were considered for final analyses on a per protocol basis. No changes in serum proteins, albumin, immunoglobulins, and secretory IgA were observed. Antibodies against influenza B and pneumococcus increased significantly from weeks 0 to 8, with no significant differences between groups. Antibodies against influenza A did not increase. No effects of prebiotics on interleukin-4 and interferon-gamma secretion by cultured monocytes were observed.

CONCLUSIONS

No immunological effects of prebiotics were observed in this study.