Hypocupremia occurred in an adult with sickle cell anemia who received zinc as an antisickling agent for two years. The hypocupremia was associated with microcytosis and relative neutropenia. Administration of copper resulted in an increase in RBC size and leukocyte counts. We have since observed hypoceruloplasminemia of varying degrees in several other sickle cell anemia patients who were receiving oral zinc therapy. This complication was easily corrected by copper supplementation.

Zinc is determined in neutrophils and lymphocytes (isolated from whole blood on discontinuous gradients of Ficoll-Hypaque) and in microliter quantities of plasma and erythrocytes by flameless atomic absorption spectrophotometry with greater sensitivity than with conventional flame atomic absorption spectrophotometry. Before analysis, neutrophils and lymphocytes are digested with nitric acid and diluted with de-ionized water. Plasma and erythrocytes required no digestion, only dilution. Overall CVs were 4.0, 3.0, 5.0, and 4.6% for neutrophils, lymphocytes, erythrocytes, and plasma, respectively. Matrix effects were fully compensated for by use of standard solutions that simulated the sample matrix. Results for plasma and erythrocytes agreed with those obtained by the conventional technique.

The effects of a mild zinc-deficient state in humans were studied. Four male volunteers received restricted zinc intake for several weeks under strict metabolic conditions. As a result of dietary zinc restriction, a decrease in zinc concentration of plasma, erythrocytes, leukocytes, and urine was observed. Changes in the activities of zinc-dependent enzymes in the plasma such as alkaline phosphatase and ribonuclease were also related to the dietary zinc status. An adverse effect of zinc restriction on total protein, total collagen, ribonucleic acid, and the activity of deoxythymidine kinase (a zinc-dependent enzyme) in the sponge connective tissue of the two volunteers in whom this test was done was noted. During the zinc restriction period, the ammonia level in the plasma was elevated. Weight loss occurred in all subjects as a result of dietary zinc restriction. Inasmuch as the zinc-deficient state was mild, this study provides a basis for developing diagnostic criteria for zinc deficiency in humans.

The effects of zinc deficiency on the activity of hepatic ornithine carbamoyltransferase (OCT) and plasma ammonia were studied in rats. One group received (ad libitum) zinc-deficient diet containing 2 ppm zinc and the other group received a diet containing 110 ppm zinc (group pair-fed control) equal to the amount consumed by zinc-deficient rats during the previous 24 h. Rats were killed at weekly intervals. Blood urea nitrogen (BUN), plasma ammonia, and hepatic OCT activity were determined. By end of the 1st wk on zinc-deficient diet, the plasma ammonia levels became significantly higher than those of the controls and remained elevated thoughout the study period. BUN increased initially for 2 wk in the deficient rats, but by the end of 4 wk the levels were lower than in the controls. The hepatic OCT activity in deficient animals was significantly lowered as compared to the controls by the 3rd wk. It is concluded that an increase in plasma ammonia may occur as a result of deficiency of zinc.

Previously, we have documented primary testicular failure in adult male subjects with sickle cell anemia. We have also reported the occurrence of zinc deficiency and suggested that androgen deficiency may be related to zinc deficiency in such patients. In this study, we present data with respect to the efferent of oral zinc supplementation on serum testosterone levels in adult male patients with sickle cell anemia. An increase in serum testosterone, neutrophil zinc, and neutrophil alkaline phosphatase activity ws observed in the zinc-supplemented group in comparison with the group on placebo. Additionally, body weight increased and serum lactic dehydrogenase activity decrease in response to zinc supplementation. We conclude that androgen deficiency in adult male subjects with sickle cell anemia is correctable with zinc supplementation and that the determination of neutrophil zinc and alkaline phosphatase activity in the neutrophils may be utilized as good indicators of body zinc status in such subjects.