Camila Xavier Alves

Positive effects of zinc supplementation on growth, GH, IGF1, and IGFBP3 in eutrophic children.

Abstract Zinc is an essential micronutrient for growth and development. Its deficiency causes growth retardation in children and adolescents. The present study analyzes the effect of zinc on growth hormone (GH) secretion, insulin-like growth factor 1 (IGF1), and insulin-like growth factor-binding protein 3 (IGFBP3) in normal children before puberty. Thirty normal children were studied, 15 boys and 15 girls, aged 6–9 years. They were orally supplemented with 5 mg Zn/day for 3 months and 0.06537 mg Zn/kg body weight was injected before and after oral supplementation. Dietary intake and anthropometric measurements were assessed at baseline and end of study. Plasma GH levels increased during intravenous zinc administration and IGF1 and IGFBP3 increased after oral zinc supplementation. There was a positive correlation between the areas under the curves of GH and zinc after oral supplementation. Zinc supplementation was possibly effective in improving the body zinc status of the children, secretory levels of IGF1 and IGFBP3, GH potentialization, and height.

Zinc pharmacokinetic parameters in the determination of body zinc status in children

Background/Objectives:Serum or tissue zinc concentrations are often used to assess body zinc status. However, all of these methods are relatively inaccurate. Thus, we investigated three different kinetic methods for the determination of zinc clearance to establish which of these could detect small changes in the body zinc status of children.Subjects/Methods:Forty apparently healthy children were studied. Renal handling of zinc was investigated during intravenous zinc administration (0.06537 mg Zn/kg of body weight), both before and after oral zinc supplementation (5 mg Zn/day for 3 months). Three kinetic methods were used to determine zinc clearance: CZn-Formula A and CZn-Formula B were both used to calculate systemic clearance; the first is a general formula and the second is used for the specific analysis of a single-compartment model; CZn-Formula C is widely used in medical practices to analyze kinetic routine.Results:Basal serum zinc values, which were within the reference range for healthy children, increased significantly after oral zinc supplementation. The three formulas used gave different results for zinc clearance both before and after oral zinc supplementation. CZn-Formula B showed a positive correlation with basal serum zinc concentration after oral supplementation (R2=0.1172, P=0.0306). In addition, CZn-Formula B (P=0.0002) was more effective than CZn-Formula A (P=0.6028) and CZn-Formula C (P=0.0732) in detecting small variations in body zinc status.Conclusions:All three of the formulas used are suitable for studying zinc kinetics; however, CZn-Formula B is particularly effective at detecting small changes in body zinc status in healthy children.

Influence of basal energy expenditure and body composition on bone mineral density in postmenopausal women

Background The aim of this study was to investigate the influence of body mass index, body weight, lean mass, fat mass, and basal energy expenditure on bone mineral density in postmenopausal women. Methods This was a cross-sectional, descriptive study of a sample of 50 women, with minimum time since menopause between 1 and 10 years. Bone mineral density was assessed at the lumbar spine (L2–L4), femoral neck, Ward’s triangle, and trochanter using dual-energy X-ray absorptiometry. Body mass index, lean mass, fat mass, and basal energy expenditure were measured by bioimpedance. Results The mean age of the women was 51.49 ± 3.86 years and time since menopause was 3.50 ± 2.59 years. Significant negative correlations were found between chronological age and lumbar spine, femoral neck, Ward’s triangle, and trochanteric bone mineral density. In regard to time since menopause, we also observed significant negative correlations with bone mineral density at the lumbar spine and Ward’s triangle. The following significant positive correlations were recorded: body mass index with bone mineral density at the femoral neck and trochanter; fat mass with bone mineral density at the femoral neck and trochanter; lean mass with bone mineral density at the lumbar spine, femoral neck, and trochanter; and basal energy expenditure with bone mineral density at all sites assessed. On the other hand, the multiple linear regression model showed that: 20.2% of bone mineral density variability at the lumbar spine is related to lean mass and time since menopause; 22.3% of bone mineral density variability at the femoral neck is related to body weight and age; 18.9% of bone mineral density variability at Ward’s triangle is related to age and basal energy expenditure; and 39% of bone mineral density variability at the trochanter is related to body mass index, age, and menarche. Conclusion Changes in bone mineral density, specific for each skeletal site, are influenced by age, time since menopause, body weight, body mass index, lean mass, and basal energy expenditure. Lean mass and basal energy expenditure positively influenced bone mineral density at the lumbar spine and Ward’s triangle, with a predominance of trabecular bone.

Bioelectrical impedance vector analysis for evaluating zinc supplementation in prepubertal and healthy children

Background The prevalence of abnormal nutritional status has increased in children and adolescents. Nutritional assessment is important for monitoring the health and nutritional status. Bioelectrical impedance vector analysis (BIVA) combines changes in tissue hydration and structure and body composition that can be assessed. Objectives The objective of this study was to use BIVA to evaluate nutritional status in 60 prepubertal children, aged between 8 and 9 years, supplemented with zinc, to detect possible changes in body composition. Design We performed a randomized, controlled, triple-blind study. The children were divided into the control group (CG; sorbitol 10%, n=29) or the experimental group (EG; 10 mg Zn/day, n=31), and the duration of the experiment was 3 months. Anthropometric assessments were performed for all of the children. Results The body mass index-for-age increased after oral zinc supplementation in the EG (p=0.005). BIVA indicated that the CG demonstrated a tendency for dehydration and decreased soft tissue and the EG demonstrated a tendency for increased soft tissue, primarily the fat-free mass. After analyses of BIVA ellipses, we observed that this method could detect improvements in body composition in healthy children supplemented with zinc. Conclusions These results suggest that BIVA could be an auxiliary method for studying a small population undergoing zinc intervention.

Serum zinc reference intervals and its relationship with dietary, functional, and biochemical indicators in 6- to 9-year-old healthy children

Background Zinc is an important cause of morbidity, particularly among young children. The dietary, functional, and biochemical indicators should be used to assess zinc status and to indicate the need for zinc interventions. Objective The purpose of this study was to determine the zinc status and reference intervals for serum zinc concentration considering dietary, functional, and biochemical indicators in apparently healthy children in the Northeast Region of Brazil. Design The cross-sectional study included 131 healthy children: 72 girls and 59 boys, aged between 6 and 9 years. Anthropometric assessment was made by body mass index (BMI) and age; dietary assessment by prospective 3-day food register, and an evaluation of total proteins was performed. Zinc in the serum samples was analyzed in triplicate in the same assay flame, using atomic absorption spectrophotometry. Results With respect to dietary assessment, only the intake of fiber and calcium was below the recommendations by age and gender. All subjects were eutrophic according to BMI and age classification. Zinc intake correlated with energy (p=0.0019), protein (p=0.0054), fat (p<0.0001), carbohydrate (p=0.0305), fiber (p=0.0465), calcium (p=0.0006), and iron (p=0.0003) intakes. Serum zinc correlated with protein intake (p=0.0145) and serum albumin (p=0.0141), globulin (p=0.0041), and albumin/globulin ratio (p=0.0043). Biochemical parameters were all within the normal reference range. Reference intervals for basal serum zinc concentration were 0.70–1.14 µg/mL in boys, 0.73–1.17 µg/mL in girls, and 0.72–1.15 µg/mL in the total population. Conclusions This study presents pediatric reference intervals for serum zinc concentration, considering dietary, functional, and biochemical indicators, which are useful to establish the zinc status in specific groups. In this regard, there are few studies in the literature conducted under these conditions, which make it an innovative methodology.

PROTOCOLO DIFERENCIADO PARA TERAPIA NUTRICIONAL NA ESCLEROSE LATERAL AMIOTRÓFICA

Objective: To discuss the nutritional therapy in Amyotrophic Lateral Sclerosis (ALS), sharing a protocol performed and used by a specialized ambulatory care service. Material and Methods: The theoretical foundation of this paper was based on the literature published in both PubMed and ISI Web of Science, using “amyrotrophic lateral sclerosis” and “nutrition” as key-words. Results and Discussion: In brief, ALS is a rare neurodegenerative disease with poor prognosis and palliative treatment. Malnutrition is very common in these patients and increases the risk of death among them. Nutritional therapy is essential and must be integrated into a multidisciplinary care. Nutritional monitoring is recommended at least once every three months. Nutritional assessment, high-calorie and high-protein diet with an adequate amount of water and fiber are recommended. In addition, micronutrients, especially antioxidants, must reach the Recommended Dietary Allowances. A diet texture modification for dysphagia is indicated and enteral nutrition should be demystified to patients and care givers during the follow-up care. ALS patients are potential candidates to use enteral nutrition, which should be indicated in cases of significant dysphagia or impaired respiratory function associated with low food intake, body mass index less than 18.5 or 22.0 kg/m² (for adults or elderlies, respectively), and/or body weight loss above 10%. Conclusion: We suggest the standardization of nutritional therapy in ALS and the establishment of a distinct protocol in clinical practice. Thus, malnutrition can be avoided or minimized, contributing to a better quality of life and survival of these patients. DESCRIPTORS: Amyotrophic Lateral Sclerosis. Nutrition Therapy. Recommended Dietary Allowances.

Uso de simbiótico no tratamento de pacientes obstipados com esclerose lateral amiotrófica

Introduction: The use of synbiotic in the management of constipation seems to be promising, particularly in patients with amyotrophic lateral sclerosis (ALS) which have constipation as a frequent symptom. Objective: To evaluate the effect of synbiotic supplementation on intestinal function of constipated patients with ALS. Materials and Methods: This interventional study was performed with ALS patients followed at the ALS multidisciplinary ambulatory of Hospital Universitario Onofre Lopes (HUOL) at the Federal University of Rio Grande do Norte (UFRN). Subjects were arranged in three groups: 10 healthy controls (group 1), 10 ALS constipated patients (group 2), and 10 ALS non-constipated patients (group 3). All subjects received synbiotic supplementation (6g/day) during 15 days and their intestinal function was monitored daily. Results: We studied 30 subjects (13 male and 17 female) with mean age 54.3 ± 10.6 years. Group 1 didn’t show major modifications in the parameters observed. Nevertheless, groups 2 and 3 improved the intestinal function, with increased frequency of bowel movements, improved stool consistency and less evacuation effort. These benefits were observed after one-week of synbiotic supplementation. Conclusion: Regular use of synbiotic can improve intestinal function in both constipated and non-constipated ALS patients.