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  • %0 ART
  • %T Obesity, voracity, and short stature : the impact of glutamate on the regulation of appetite
  • %A HERMANUSSEN M.
  • %A GARCIA A. P.
  • %A SUNDER M.
  • %A VOIGT M.
  • %A SALAZAR V.
  • %A TRESGUERRES J. A. F.
  • %G 0954-3007
  • %I Nature Publishing Group
  • %C Basingstoke, ROYAUME-UNI
  • %D 2006
  • %V 60
  • %N 1
  • %P 25-31
  • %P 7
  • %O Anglais
  • %K Central nervous system
  • %K Système nerveux central
  • %K Hypothalamus
  • %K Hypothalamus
  • %K Encephalon
  • %K Encéphale
  • %K Neurotransmitter
  • %K Neurotransmetteur
  • %K Excitatory aminoacid
  • %K Aminoacide excitateur
  • %K Nutrition disorder
  • %K Trouble nutrition
  • %K Nutritional status
  • %K Etat nutritionnel
  • %K Nutrition
  • %K Nutrition
  • %K Arcuate nucleus
  • %K Noyau arqué
  • %K Appetite
  • %K Appétit
  • %K Regulation
  • %K Réglementation
  • %K Regulation(control)
  • %K Régulation
  • %K Glutamate
  • %K Glutamate
  • %K Growth retardation
  • %K Retard staturopondéral
  • %K Obesity
  • %K Obésité
  • %K obesity
  • %K voracity
  • %K short stature
  • %K glutamate
  • %K arcuate nucleus
  • %X Background: World-wide obesity has risen to alarming levels. We present experimental support for a new and very challenging hypothesis linking obesity, voracity, and growth hormone (GH) deficiency, to the consumption of elevated amounts of the amino-acid glutamate (GLU). Supraphysiological doses of GLU are toxic for neuronal cells. Methods: Human data were obtained from 807592 German conscripts born between 1974 and 1978, and from 1 432 368 women of the German birth statistics (deutsche Perinatalerhebung) 1995-1997. The effects of orally administered monosodium glutamate (MSG) were investigated in 30 pregnant Wistar rats and their offspring. Pregnant animals either received no extra MSG, or 2.5 g MSG, or 5 g MSG per day, up to the end of the weaning period. In all, 2.5 g, respectively 5 g, MSG accounted for some 10%, respectively 20%, of dry weight of the average daily food ration. After weaning, MSG feeding was continued in the offspring. Findings: Morbid obesity associates with short stature. Average stature of conscripts progressively declines when body mass index increases above 38 kg/m[2]. Also morbidly obese young women are shorter than average though to a lesser extent than conscripts. Oral administration of MSG to pregnant rats affects birth weight of the offspring. Maternal feeding with 5 g MSG per day results in severe birth weight reduction (P<0.01). Weight increments remain subnormal when MSG feeding to the mothers is maintained during weaning (P<0.01). GH serum levels are affected in animals that received MSG during prenatal life via maternal feeding. Animals that are kept on high MSG diet (5 g MSG per day) continue to show serum GH levels that are as low or even lower than those of MSG injected animals (P<0.05), both at day 30 and at day 90 of life. Animals that were kept on medium MSG diet (2.5 g MSG per day) showed low serum GH levels at day 30 of life (P<0.01), but seemed to partially recover before day 90. Almost identical results were observed in IGF-1 serum levels. Oral MSG resulted in dose dependent voracity. The animals fed 5 g MSG per day increased water uptake by threefold (P<0.01), and food uptake by almost two-fold (P<0.01). The influence of MSG is in general more marked in males than in females. Interpretation: GLU is a widely used nutritional substance that potentially exhibits significant neuronal toxicity. Voracity, and impaired GH secretion are the two major characteristics of parenterally administered GLU-induced neuronal damage. GLU maintains its toxicity in animals even when administered orally. Males appear to be more sensitive than females. The present study for the first time demonstrates, that a widely used nutritional monosubstance - the flavouring agent MSG - at concentrations that only slightly surpass those found in everyday human food, exhibits significant potential for damaging the hypothalamic regulation of appetite, and thereby determines the propensity of world-wide obesity. We suggest to reconsider the recommended daily allowances of amino acids and nutritional protein, and to abstain from the popular protein-rich diets, and particularly from adding the flavouring agents MSG. 
  • %S European journal of clinical nutrition

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