Endogeneous increase of proteinase inhibitors as a possible mechanism of adaptation and subclinical undernutrition resulting in stunting

There is evidence that the organism tries to keep an optimal relationship of weight to a given height in the case of subclinical undernutrition. The underlying mechanism seems to regulate the growth spurt so that a beneficial relationship of weight on cost of the height spurt can be maintained. Proteinase inhibitors might be involved in such an adaptation process. In children from the rural sector of Thailand the serum proteinase inhibitor alpha2-macroglobulin was found to be elevated above well-nourished children from the urban area. 3-Methylhistidine excretion in the urine was lower in the village children compared with those of the children from Bangkok. Similar observations were made in rat experiments. It is hypothised that alpha2-macroglobulin elevation during nutritional stress might be one of the mechanism which causes the children's organism to try and find an optimal relationship between catabolism and synthesis resulting in stunting.