Boron deprivation

Nielsen, F.H. 1994. Biochemical and physiologic consequences of boron deprivation in humans. Environ. Health Perspec. 102(Suppl. 7) 59-63. 

Nielsen FH (1984a) Effects in rats of boron deprivation and of interactions between boron and fluoride, aluminium, magnesium, or calcium. In Mills CF, Bremner I and Chesters JK, eds. Trace Element in Man and Animals-5. Commonwealth Agricultural Bureaux, Famham Royal, UK, pp. 271-275. 

Much evidence exists to support the contention that boron has beneficial effects on bone. The effects of boron, however, are most evident in the presence of suboptimal status of another nutrient important in bone formation or remodeling. In chicks, boron deprivation (0.465 mgkg diet) exacerbates the distortion of marrow sprouts (location of calcified scaffold erosion and new bone formation) and delay in imtiation of cartilage calcification in bones during marginal vitamin D deficiency (Hunt 1996). In humans, estrogen therapy to maintain bones increases serum 17P-estra-diol this increase is depressed when dietary boron intake is low (0.25-0.35 g per day) (Nielsen 1996, 1997). Boron deprivation also can exacerbate the increase in serum calcitonin and osteocalcin caused by low dietary copper and magnesium in humans. 

Both brain function and composition are affected by dietary boron (Nielsen 1996, Pen-land 1998). Assessments of both animal models and humans found that boron deprivation results in decreased brain electrical activity similar to that observed in nonspecific malnutrition. Boron deprivation also resulted in poorer performance in tasks of motor speed and dexterity, attention, and short-term memory in humans. Increased copper and calcium concentrations in total brain and increased phosphorus in the cerebellum have been found in boron-deprived rats. Boron reportedly can restore the a-hel-ical conformation of (l-amyloid peptide (1 -40) disrupted by aluminum (Ramakrishna etal. 1997). 

No requirement for boron in mammals is proven, although evidence is accumulating suggesting that boron may be an essential nutrient. Boron is related to normal energy utilization, immune function, and metabolism of bone, minerals, and lipids. Boron deficiency (<0.04 mg B/kg ration of dams) impairs early embryonic development in rodents these effects were not observed at 2.0 mg B/kg ration. Boron deprivation in animals and humans results in decreased brain electrical activity similar to that observed in nonspecific malnutrition, and reduced cognitive and psychomotor function. Learning performance (manual dexterity, eye-hand coordination, memory, attention, perception) in humans was... 

Nielsen, F.H., Penland, J.G. Boron deprivation alters rat behaviour and brain mineral composition differently when fish oil instead of safflower oil is the dietary fat source. Nutr. Neurosci. 2006 9 105-112. 

Nielsen, F.H. Boron deprivation decreases liver 5-adenosyhnethionine and spermidine and increases plasma homocysteine and cysteine in rats. J. Trace Elem. Med. Biol. 2009 23 204-213. 

Nielsen, F.H. The alteration of magnesium, calcium and phosphorous metabohsm by dietary magnesium deprivation in postmenopausal women is not affected by dietary boron deprivation. Magnesium Res. 2004 17 197-210. 

Penland, J.G. Quabtative analysis of EEG effects following experimental marginal magnesium and boron deprivation. Magnesium Res. 1995a 8 341-358. 

It was long thought that boron was not required by human beings, but more recent studies suggest that we may need 30 pg / day.d Tire possible functions are uncertain. Animals deprived of boron show effects on bone, kidney, and brain as well as a relationship to the metabolism of calcium, copper, and nitrogen. Nielson proposed a signaling function, perhaps via phosphoinositides, in animals.b... 

Boron is an essential trace plant nutrient. Although its exact function has not yet been established, deprivation of boron alfects plant growth and in boron-poor soils, crop yields are diminished. An important application of borax is in borate fertilizers. In contrast, the toxicides of boric acid and borax to animal life are sufficient for them to be used as insecticides,... 

In a later study in women who were deprived of dietary magnesium, boron suppl entation resulted in a decrease in the serum 17b-estradiol concentration (Nielsen, 2004), and the plasma progesterone concentration was influenced by a boron x magnesium interaction. This study confirmed the existence of an interaction between boron and other nutrients, spedficaUy magnesium, under conditions of metabolic stress (Nielsen, 2008). 

The quality of the experimental evidence for nutritional essentiality varies widely for the ultratrace elements. The evidence for the essentiality of three elements, iodine, molybdenum and selenium, is substantial and noncontroversial specific biochemical functions have been defined for these elements. The nutritional importance of iodine and selenium are such that they have separate entries in this encyclopedia. Molybdenum, however, is given very little nutritional attention, apparently because a deficiency of this element has not been unequivocally identified in humans other than individuals nourished by total parenteral nutrition or with genetic defects causing disturbances in metabolic pathways involving this element. Specific biochemical functions have not been defined for the other 15 ultratrace elements listed above. Thus, their essentiality is based on circumstantial evidence, which most often is that a dietary deprivation in an animal model results in a suboptimal biological function that is preventable or reversible by an intake of physiological amounts of the element in question. Often the circumstantial evidence includes an identified essential function in a lower form of life, and biochemical actions consistent with a biological role or beneficial action in humans. The circumstantial evidence for essentiality is substantial for arsenic, boron, chromium, nickel, silicon, and vanadium. The evidence for essentiality for the... 

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