Manganese deficiency, effect

Zidenberg-Cherr S, Hurley ES, Eonnerdal B, et al. 1985. Manganese deficiency Effects on susceptibility to ethanol toxicity in rats. J Nutr 115 460-467. 

Nitrogen is normally supplied as an ammonium compound in dtric acid fermentations and suffident has to be supplied to enable the effect of manganese deficiency (increased levels of ammonium in the metabolic pool) to occur. Remember that increased metabolic pool ammonium has the effect of releasing the allosteric controls exerted on phosphofructokinase. 

Golub MS, Han B, Keen CL, et al. 1992b. Effects of dietary aluminum excess and manganese deficiency on neurobehavioral endpoints in adult mice. Toxicol Appl Pharmacol 112 154-160. 

Because of the blood lowering cholesterol effects of a manganese deficiency, involvement of manganese in lipid metabolism has been a topic of research interest as reviewed by Johnson and Kies in this volume. 

Little is known of the in vivo effect of manganese on cholesterol metabolism. Doisy (6) observed a decrease in serum cholesterol (from 206 to 80 mg/dl) in a single manganese deficient human subject. Reports of other human studies conducted to determine the influence of dietary manganese on cholesterol metabolism were not found. 

Manganese has a further role as a lipotropic agent. Amdur and associates (9) found that hepatic lipid concentration was increased by manganese deficiency. Plumlee et al. (10) conducted four experiments to determine the effect of manganese deficiency in swine and found that total body fat and liver lipid concentrations were increased by manganese deficiency. 

Bell, L. T, and Hurley, L, S. (1973). Ultrastructural effects of manganese deficiency in liver, heart, kidney, and pancreas of mice. Luh fniwsl. 29, 723-736. 

Hurley LS, Keen CL, Baly DL. 1984. Manganese deficiency and toxicity Effects on carbohydrate metabolism in the rat. Neurotoxicology 5 97-104. 

The effect of manganese deficiency or excess on carbohydrate homeostasis have been studied by Keen, Hmley and coworkers, with some focus on pyruvate carboxylase and PEP carboxykinase [302-304]. Other evidence indicates that Mn(II) has an insulin-mimetic effect, acting to stimulate protein kinases or phosphatases that control enzymes involved in glycolysis, gluconeogenesis, or the hexose mono-P pathway [305-307]. A key role of Mn(II) in mucopolysaccharide metabolism has long been recognized [6]. 

The effects of long-term manganese deficiencies on bone structure and resorption of bone particles has been investigated by Strause and coworkers [472,473]. Furthermore, dietary levels of the element have been reported to alter the utilization of selenium [474]. 

Conversely, an excess soil P may effect the uptake of some micronutrient elements. A high P content can induce a zinc deficiency in the plant, even if sufficient zinc is present in the soil. On the other hand, the uptake of manganese from alkaline manganese-deficient soils can be increased by the presence of phosphatic fertilisers. There is also some evidence that excessive and prolonged buildup of phosphatic fertilisers in the soil might lead to toxic effects due to the trace quantities of certain metals (e.g. Cd above) in the fertilisers [38,59-61]. 

The effect of GTF and chromium was further brought into question by the study of Shepherd et al. [32). These investigators found that potentiation of the action of suboptimal concentrations of insulin by GTF is more pronounced in adipocytes from rats fed a tomla yeast diet than in rats fed other diets differing only in the protein source. The authors conclude that the diets did not differ in amino acids, GTF active material, chromium, or 21 other trace elements measured in the diets. However, the level of manganese was low in all the diets, particularly in the torula yeast diet. Since manganese deficiencies have previously been implicated in abnormal glucose metabolism, this deficiency could be responsible for these effects. 

Ma H, Kubicek C, Rohr M. Metabolic effects of manganese deficiency in Aspergillus niger. evidence for increased protein degradation. Arch Microbiol 1985 141 266-8. 

Manganese deficiency has been found in ruminants, pigs and poultry. The effects of acute deficiency are similar in all species and include retarded growth, skeletal abnormalities, ataxia of the newborn and reproductive failure. Manganese, through its activation of glycosyl transferases, is required for the formation of the mucopolysaccharide that forms the organic matrix of bone. 

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