Lack Of Zinc Research Articles

Obstructive sleep apnea syndrome patients and hypozincemia

Physiologic stresses have been reported to cause a lack of zinc. Obstructive sleep apnea syndrome (OSAS) is a disorder that gives stress, including sleep deprivation or hypoxia. Therefore, it is predicted that the serum zinc level might be decreased in OSAS patients. We studied 16 patients with OSAS who underwent polysomnogram. Of the 16 cases of the OSAS group, 5 cases showed hypozincemia, whereas no cases showing hypozincemia were observed in the non-OSAS group. The χ2-test revealed P < 0.05. Although administration of zinc was not performed until the time of blood drawing, three of the four cases with hypozincemia showed improvement.

Zinc deficiency in men with Crohn's disease may contribute to poor sperm function and male infertility

Summary. In Great Britain, married couples were reported to have between 1.9 and 2.1 children, while men with Crohn's disease had a mean of 1.2 and of 0.4 children before and after diagnosis, respectively. The role of zinc for male fertility is essential. Although lack of zinc in Crohn's disease is well established in up to 70% of patients, a possible relation between zinc deficiency and male subfertility in Crohn's disease remains unclear. This study is aimed at examining a possible link between zinc deficiency in men with Crohn's disease and male subfertility in this group of patients.

Zinc deficiency in men with Crohn's disease may contribute to poor sperm function and male infertility.

In Great Britain, married couples were reported to have between 1.9 and 2.1 children, while men with Crohn's disease had a mean of 1.2 and of 0.4 children before and after diagnosis, respectively. The role of zinc for male fertility is essential. Although lack of zinc in Crohn's disease is well established in up to 70% of patients, a possible relation between zinc deficiency and male subfertility in Crohn's disease remains unclear. This study is aimed at examining a possible link between zinc deficiency in men with Crohn's disease and male subfertility in this group of patients.

Immunobiology of gestational zinc deficiency

The trace element zinc is an essential micronutrient for the proper functioning of the immune system. Zinc deficiency leads to impaired function of the unspecific and specific immune response and consequently to an increased susceptibility to bacterial, viral and fungal infections. Immunological defects are not only seen in pronounced but even in marginal and moderate zinc deficiency. Lack of zinc is especially harmful for the development of the immune system, which stresses the importance of a balanced zinc level during pregnancy. However, gestational zinc deficiency due to an imbalance between intake and increased requirements is a common problem world-wide. In animals, gestational zinc deficiency results in reduced thymic and spleen size and depressed active and passive immunity in the infant. For example, depressed immunoglobulin levels, altered antibody repertoire, reduced proliferative response of lymphocytes and diminished neutrophil functions have been reported. Interestingly, immune defects caused by prenatal zinc deficiency, such as depressed antibody levels and lymphocyte proliferation, may even persist in subsequent generations and are not reversible by postnatal zinc administration. Since gestational zinc deficiency is a common problem throughout all cultures and socioeconomic levels, it might have immense consequences for the health status of the population. Based on a summary of the immunobiology of zinc, this article reviews the significance of zinc deficiency during pregnancy and the effect of gestational zinc deficiency on passive and active immunity in the infant. It provides a rational basis for both immunological laboratory investigations and field studies, such as large community-based zinc supplementation trials in pregnant women.

Immunobiology of gestational zinc deficiency

The trace element zinc is an essential micronutrient for the proper functioning of the immune system. Zinc deficiency leads to impaired function of the unspecific and specific immune response and consequently to an increased susceptibility to bacterial, viral and fungal infections. Immunological defects are not only seen in pronounced but even in marginal and moderate zinc deficiency. Lack of zinc is especially harmful for the development of the immune system, which stresses the importance of a balanced zinc level during pregnancy. However, gestational zinc deficiency due to an imbalance between intake and increased requirements is a common problem world-wide. In animals, gestational zinc deficiency results in reduced thymic and spleen size and depressed active and passive immunity in the infant. For example, depressed immunoglobulin levels, altered antibody repertoire, reduced proliferative response of lymphocytes and diminished neutrophil functions have been reported. Interestingly, immune defects caused by prenatal zinc deficiency, such as depressed antibody levels and lymphocyte proliferation, may even persist in subsequent generations and are not reversible by postnatal zinc administration. Since gestational zinc deficiency is a common problem throughout all cultures and socioeconomic levels, it might have immense consequences for the health status of the population. Based on a summary of the immunobiology of zinc, this article reviews the significance of zinc deficiency during pregnancy and the effect of gestational zinc deficiency on passive and active immunity in the infant. It provides a rational basis for both immunological laboratory investigations and field studies, such as large community-based zinc supplementation trials in pregnant women.

P-2. 成長期の亜鉛不足による 1α-OH-D_3 の影響 : 軟骨内骨化による骨形成(第 60 回九州歯科学会総会講演抄録)

P-2. 成長期の亜鉛不足による 1α-OH-D_3 の影響 : 軟骨内骨化による骨形成(第 60 回九州歯科学会総会講演抄録)

Effects of zinc on the reactive oxygen species generating capacity of human neutrophils and on the serum opsonic activity in vitro.

To investigate the effects of zinc on non-specific immune functions, we used the chemiluminescence method to examine the capacity of human neutrophils to produce reactive oxygen species and accompanying serum opsonic activity. When neutrophils were stimulated with both opsonized zymosan and phorbol myristate acetate in the presence of 1-10(-3) mmol/L zinc lucigenin-dependent CL responses were stable or declined, whereas luminol-dependent CL responses were significantly enhanced. The results suggest that zinc activates protein kinase C and promotes MPO degranulation and ROS metabolism, especially in hypochlorous acid production, which have the direct action of causing microbial death. Further, the lucigen-dependent CL response stimulated with OZ was strongly enhanced by anti-MPO antibodies, whereas the enhancement was less in the presence of zinc, suggesting that zinc may suppress the receptor-mediated signal transduction process. Both responses were inhibited at 10 mmol/L. Serum opsonic activity was enhanced by zinc at 10(-4) and 10(-3) mmol/L but reduced at 10 mmol/L. These data indicate that addition of zinc around and above normal physiological concentrations facilitates neutrophil functional activity and serum opsonic activity, whereas these are inhibited by a lack of zinc or an excessive amount, suggesting that zinc is essential for optimal functioning of non-specific immunity.

Failure of IGF-I Infusion to Promote Growth in Zn Deficient Hypophysectomized Rats

The retarded growth of zinc-deficient rats is associated with low plasma insulin-like growth factor-I (IGF-I). To determine whether the low circulating IGF-I concentrations are responsible for the stunted growth, the growth response of zinc-deficient hypophysectomized rats to supplementation with recombinant human IGF-I (hIGF-I) was investigated. There were three dietary groups: zinc-deficient (0.9 mg zinc/kg diet), controls (66 mg zinc/kg diet) and zinc-adequate pair-fed (66 mg zinc/kg diet). All rats in each group received hIGF-I (150 micrograms/day) by subcutaneous infusion for 12 days, except for half of the animals in the control group which were sham-treated and which received vehicle infusion for the same period of time. The magnitude of the change was small, nevertheless infusion of hIGF-I significantly increased (p < 0.05) the body weight, tail length, liver weight and tibial epiphyseal width of control animals. This growth effect of hIGF-I was inhibited by lack of zinc in the diet, as evidenced by continuous weight loss, no increase in tail length and lowered tibial epiphyseal width in zinc-deficient animals. We conclude that systemic supplementation of hIGF-I can promote growth in hypophysectomized rats. The absence of weight gain and bone growth in zinc-deficient animals during the infusion period suggests that the growth promoting effect of circulating IGF-I is impaired by zinc deficiency.

Basal metallothionein in tumors: Widespread presence of apoprotein

A survey has been conducted of solid and ascites tumors from mice and solid tumors in rats for the presence of metallothionein or metallothionein-like protein. In most tumors, a positive identification was made on the basis of Sephadex G-75 and HPLC-DEAE chromatography followed by competitive radioimmunoassay for metallothionein. Apometallothionein was revealed in a number of tumors for the first time by comparing the Sephadex G-75 chromatographic profiles of Zn in native cytosol and Cd in cytosol incubated briefly with CdCl 2 to saturate free binding sites on the protein before Sephadex G-75 chromatography. In two cases unsaturation of metallothionein was correlated with a lack of zinc in the ascites fluid which supplies the tumor with zinc.

Serum selenium concentration and disease progress in patients with HIV infection

The selenium concentration in the serum of 67 patients with HIV infection was measured to determine whether selenium deficiency occurred in the different stages of the disease. In the first stage of the study, patients were divided into four groups: symptom-free subjects, PGL (persistent generalized lymphadenopathy), ARC (AIDS related complex), and AIDS (acquired immunodeficiency syndrome). Selenium concentrations were normal in HIV antibody positive symptom-free subjects (1.18 +/- 0.27 mumol/L) and lower than normal in the other three groups (p less than 0.001). There was a significant correlation (p less than 0.001) between selenium levels and values of hemoglobin and erythrocyte sedimentation rate. Selenium deficiency was in no case associated with a lack of zinc in serum (also determined in all patients). In the second stage of the study, 12 patients were treated for a period of two months with low doses of selenium to assess whether such supplementation was able to restore their impaired immunological and hematological functions. The therapy increased serum selenium concentrations (from 0.77 +/- 0.23 to 1.44 +/- 0.41 mumol/L) and symptomatic improvements were noted. However, no changes were observed in the immunological and hematological parameters.

Carbonic anhydrase activity as an indicator of zinc deficiency in pecan leaves

An extraction method was developed to examine if enzymatic reaction of carbonic anhydrase in pecan (Carya illinoensis (Wang.) K Koch) leaves can replace the ordinary mineral detection tests. By comparing the extracted carbonic anhydrase activity from pecan leaves with lack of zinc and with recommended zinc level, the differences can be easily observed and used for detection of zinc deficiency.

The role of zinc deficiency in the pathogenesis of dermatoses

The interest of dermatologists in the study of zinc metabolism arose after the appearance of the article by Todd et al. (1934), in which it was indicated that a lack of zinc in the diet in rats leads to hair loss. Tucker (1955) and Dell (1958) in experiments on pigs and chickens not only confirmed the role of zinc deficiency in the genesis of alopecia areata, but also drew attention to the development of parakeratosis and histological changes in the mucous membrane of the esophagus.

Control of Ehrlich cell division by zinc

The nutritional requirement for zinc in the proliferation of normal and malignant cells has been demonstrated in a number of animal studies. A distinction is made between the effect of zinc status upon the host during carcinogenesis and tumor growth. The present studies focus on the Ehrlich ascites tumor in mice fed a semipurified zinc-deficient diet along with defined concentration of zinc in the drinking water. This model of zinc deficiency is compared with others in which chelating agents are used to create zinc-deficient conditions or the microorganismEuglena gracilis is examined in a defined zinc-deficient medium. It is reported here that Ehrlich cells remain quiescent for several weeks in severely deficient mice, suggesting their restriction to a G1 or G0 state of the cell cycle. The kinetics of thymidine and uridine uptake and incorporation into DNA and RNA in Zn-normal and Zn-deficient tumors is consistent with the inhibition of thymidine kinase and DNA polymerase in the Zn-deprived system, but with little effect on RNA synthesis. The concentration of metabolites of these labeled nucleosides in Ehrlich cells is also consistent with a primary effect upon thymidine kinase. Although the ascites fluid Zn is depressed in Zn deficiency, total cellular zinc and its distribution among cell fractions is not significantly affected. It is suggested that these effects are specific in nature and not the result of a general lack of zinc for zinc metalloproteins and other binding sites in the cell.

Inhibition of growth and nucleic acid synthesis in zinc-deficient Mycobacterium smegmatis.

SUMMARY The growth of Mycobacterium smegmatis was inhibited by lack of zinc in a glycerol + asparagine medium depleted of trace metals but enriched with iron. Addition of zinc to this medium supported full growth of the organism. Both zinc-deficient and zinc-replete cultures had the same exponential doubling time. In zinc-deficient organisms the synthesis of RNA and DNA varied with growth rate in a manner typical for nutrient-induced decreases in a variety of organisms. Zinc-deficiency led to inhibition of nicotinamide synthesis and an increase in phosphate storage as compared with zinc-replete cultures. The pH value of zinc-deficient cultures was preponderantly alkaline. The results are discussed with reference to the metabolic role of zinc ions, and the effects of zinc deficiency is compared to the effects of iron deficiency as previously reported for the same organism.

Influence du régime alimentaire sur la concentration en acides aminés non protéiques dans l'hémolymphe des larves âgées d' Agria affinis (Fall.)

Results are presented on the non-protein amino acid content in the haemolymph of Agria affinis matured larvae reared on two different diets. The first group of larvae was fed on pork liver, the second group was reared under aseptic conditions on a chemically defined diet whose amino acid mixture was similar in composition to pork liver proteins. Most amino acids were encountered in smaller amounts in diet-fed larvae. Nevertheless, aspartic acid and α-alanine were about equal in the haemolymph of both; asparagine, methionine sulphoxide, and methylhistidine were absent, and the amount of α-amino- n-butyric acid, phenylglutamic acid, proline, and serine exceeded the amount found in liver-fed larvae. The low content of glutamic acid, glutamine, and asparagine shows either a low content or a partial inhibition of transaminases and transamidases concerned in the synthesis of these substances. The transformation of glutamic acid to proline and phenylglutamic acid is done at the expense of its amidation. High concentration of serine is due to the absence of methyl-histidine whose synthesis by transmethylation might be impaired by lack of zinc in the diet.