Concomitant lysine and phosphorus addition to a wheat gluten protein diet highly amplified growth measures of rats

OBJECTIVE

In humans, the effects of lysine-fortified wheat on growth measures was much lower than that of animal experimentations that used phosphorus-containing mineral mix. It is known that wheat contains a limited amount of available phosphorus, which is believed to support growth. The aim of this study was to determine the involvement of phosphorus in growth measures of rats maintained on a lysine-supplemented wheat gluten diet.

METHODS

Forty male Sprague-Dawley (6 wk old) rats were randomly divided into four equal groups and fed wheat gluten protein (10%)-based diets with added lysine (0.6%), phosphorus (0.3%), or both (0.6% lysine and 0.3% phosphorus), ad libitum for 9 wk. Rats were monitored for changes in food intake, body weight, body and liver compositions, plasma urea nitrogen, and albumin.

RESULTS

The addition of lysine or phosphorus to wheat gluten-based diets increased energy intake modestly (∼15%), whereas their combination caused a higher increase (∼45%). Similarly, the magnitude of improvement in weight gain and energy efficiency by the addition of lysine or phosphorus (∼1g/d and 2.7g/MJ, respectively) was much lower than that of the combination (∼4g/d and 8.7g/MJ). In the phosphorus-containing groups, plasma urea nitrogen was significantly reduced and this was associated with higher body protein (%) and hepatic fat (%); whereas plasma albumin was significantly increased in the lysine-containing groups.

CONCLUSION

When using gluten protein, concomitant lysine and phosphorus availability is required to support growth measures, although phosphorus seems to have an independent effect on protein metabolism. Thus, human interventions should consider the improvement of the amino acid profile and phosphorus availability.

Metabolic syndrome among adolescents in Dubai, United Arab Emirates, is attributable to the high prevalence of low HDL levels: a cross-sectional study

BACKGROUND

Metabolic syndrome (MetS) describes a combination of risk factors that increase the risk of developing chronic diseases. The prevalences of MetS and its risk factors are increasing, especially in the Arab region. A cross-sectional study was carried out to assess the prevalences of MetS and its associated risk factors among adolescents in the United Arab Emirates (UAE).

METHODS

A total of 596 students (308 boys and 288 girls) aged 10 to 15.9 years old were recruited from 14 public secondary schools in Dubai, UAE. Anthropometric and biochemical data were measured.

RESULTS

According to the International Diabetes Federation (IDF) criteria, the prevalence of MetS was 3.7%, and it was more common among boys than girls (12 boys versus 10 girls). MetS was also more likely to be found in students who were obese or overweight than those with normal weight. The most prevalent and significant MetS risk factor was low high-density lipoprotein (HDL) cholesterol levels.

CONCLUSIONS

This study indicates the importance of carrying out further investigations about the constituents of HDL and their atherogenic effects. Additionally, these results strongly recommend setting a consensus for HDL measurement, since small variations in methodologies may lead to substantial deviations in results.

Phosphorus ingestion with a high-carbohydrate meal increased the postprandial energy expenditure of obese and lean individuals

OBJECTIVES

Phosphorus ingestion with glucose was reported to stimulate the postprandial peripheral uptake of both phosphorus and glucose, a process that favors energy production. The aim of this study was to determine whether phosphorus ingestion with a meal can affect energy metabolism.

METHODS

Overnight fasted men (eight lean and seven obese) consumed a high-carbohydrate meal (648 kcal) with either placebo or phosphorus (500 mg) tablets in a random order. Energy expenditure and substrate oxidation were monitored for 240 min using ventilated hood indirect calorimetry.

RESULTS

Phosphorus ingestion with a meal increased the postprandial energy expenditure of both lean and obese individuals (P < 0.001), although in different patterns. Alterations in postprandial substrate oxidation was highly noticeable from time 120 min onward, where phosphorus-treated lean participants exhibited a significant decrease in respiratory quotient.

CONCLUSION

Phosphorus ingestion with a high-carbohydrate meal alters postprandial energy metabolism mainly by enhancing postprandial energy expenditure that may ultimatly favor weight loss.

Urinary Magnesium, Calcium, and Phosphorus to Creatinine Ratios of Healthy Elementary School Lebanese Children

Urinary magnesium (Mg), calcium (Ca), and phosphorus (P) excretions are known to vary greatly between populations due to dietary habits, physical activity, mineral content of water, climate, genetics, and race. Thus, it is essential to determine the normal values in each population in order to assess the status as well as to diagnose any possible abnormality of metabolisms especially hypercalciuria. A study was conducted to determine urinary Mg/creatinine (Cr), Ca/Cr, and P/Cr ratios of healthy Lebanese elementary schoolchildren. Using a multi-stage cluster sampling at district, school, and class levels, a sample of 1403 children (781 boys and 622 girls), from 26 different schools, was selected. Non-fasting morning urine samples and anthropometric data were collected and analyzed. The mean Mg/Cr, Ca/Cr, and P/Cr ratios were 0.122 ± 0.075 mg/mg (0.568 ± 0.348 mM/mM), 0.084 ± 0.101 mg/mg (0.237 ± 0.286 mM/mM), and 0.692 ± 0.417 mg/mg (2.527 ± 1.524 mM/mM), respectively, with no significant difference between boys and girls (P = 0.706, 0.161, and 0.604; respectively). The 95th percentile of Mg/Cr, Ca/Cr, and P/Cr ratios fluctuated with age, showing a sharp decrease in Ca/Cr and P/Cr at the age of 10. The mean Mg/Cr, Ca/Cr, and P/Cr ratios were comparable to those of similar age groups in other populations. The 95th percentiles of Mg/Cr, Ca/Cr, and P/Cr ratios were 0.26 mg/mg (1.23 mM/mM), 0.27 mg/mg (0.76 mM/mM), and 1.48 mg/mg (5.40 mM/mM), respectively. These values can be used as cutoffs to detect abnormalities in these three minerals' metabolisms among healthy Lebanese children.