Serum Copper Levels in Pregnancy and Pre-Eclampsia

Mishandling of copper by albumin: role in redox-cycling and oxidative stress in preeclampsia plasma

OBJECTIVE

To test the hypothesis that enhanced oxidative stress during pregnancies complicated by preeclampsia is associated with improper copper (Cu) binding by plasma albumin, resulting in enhanced Cu redox-cycling activity and that altered Cu binding, in turn, is caused by interactions of excessive amounts of free fatty acids with albumin.

STUDY DESIGN

We studied binding and redox-cycling activity of Cu in 17 normal pregnancy and 17 preeclampsia plasma samples. Binding of exogenous Cu in plasma samples was quantified indirectly using spectrophotometric measurements of its complex with a specific chelator of Cu(I), bathocuproine disulfonate. Redox-cycling activity of Cu in plasma samples was estimated by electron paramagnetic resonance (EPR) spectroscopy of ascorbate radicals formed during one-electron oxidation of ascorbate by redox-active catalytic Cu. Formation of Cu/albumin complexes in model systems in the presence and absence of fatty acids was studied using EPR spectroscopy of Cu(II)/albumin.

RESULTS

We found that preeclampsia plasma (as compared to normal pregnancy plasma) (1) displays elevated endogenous ascorbate redox-cycling that is normalized by a Cu(II) chelator, cuprizone I, (2) has lowered capacity to bind and redox-regulate exogenously added Cu, and (3) responds to treatment with fatty-acid-free albumin by diminished ascorbate oxidizing activity. Conversely, addition of free fatty acid (oleic acid) to normal pregnancy plasma sample yields increased ascorbate redox-cycling activity. Our model experiments showed that Cu-dependent redox-cycling activity of purified human serum albumin is significantly increased by excess free fatty acids.

CONCLUSION

Mishandling of Cu by albumin contributes to oxidative stress in preeclampsia. Cu chelators may represent promising mechanism-based antioxidants to attenuate oxidative stress in preeclampsia.

Caeruloplasmin as demonstrated by starch gel electrophoresis

Starch gel electrophoresis has demonstrated that graded concentrations of sodium sulphate do not precipitate the serum globulins in any reasonable degree of purity. The use of this form of electrophoresis has shown that caeruloplasmin is associated with a globulin in the Fa(2) position.This technique can be employed as a screening test for patients suspected of suffering from hepatolenticular degeneration.

Fulminant hepatic failure during perinatal period in a pregnant woman with Wilson's disease

Wilson's disease associated with hepatic failure is not common and the underlying mechanism triggering the event is not known at present. We treated a 28-year-old Japanese woman with Wilson's disease who developed hepatic failure associated with hemolytic crisis just after delivery. She was diagnosed as having Wilson's disease at 12 years of age, at which time she started taking D-penicillamine. She had previously delivered two children without difficulty. When she found out she was pregnant this time, she stopped taking D-penicillamine in contrast to taking it faithfully during her first two pregnancies. On the day of delivery of her full-term baby, jaundice developed accompanied with severe hemolytic crisis. Plasma exchanges and blood transfusion were performed and D-penicillamine administration was started again. She gradually recovered and apparently was following a good clinical course. However, on day 30 the second hemolytic crisis occurred and subsequent liver failure led her to death on day 50. At autopsy her liver was cirrhotic and showed massive necrosis. Prophylactic oral administration of D-penicillamine and careful observation are therefore recommended to prevent hemolytic crisis during the perinatal period.

Distribution of serum selenium, copper, and zinc in normal human pregnancy

The distribution of the serum levels of selenium, zinc, and copper in human pregnancy at various gestational ages were determined from two ethnically and geographically different populations (Rosebud Indian Reservation and southeastern South Dakota) of 410 normal subjects. As gestation age increased, there was a significant increase and a slight decrease in the mean levels of copper and zinc, respectively. No change in the levels of selenium was observed. Significantly higher levels of both pregnancy and non-pregnancy serum copper were observed in the Rosebud population compared to that in southeastern South Dakota, possibly due to the significantly higher level of copper in the Rosebud water. No differences were observed in the zinc or selenium levels between the two populations. Serial measurements of these trace metals during the third trimester of pregnancy were performed on 18 subjects, and supported the trends described for copper and selenium. No decrease in zinc was observed in the individual subjects.

Nutritional implications of the free-radical theory of aging

Aging is the progressive accumulation of changes with time associated with and/or responsible for the ever-increasing susceptibility to disease and death. These time-related changes are attributed to the aging process. This process may be due in part to free radical reactions, largely those involving oxygen, going on continuously throughout the cells and tissues. Dietary manipulations expected to lower the rate of production of free-radical reaction damage have been shown to 1) increase the life span of mice, rats, fruit flies, nematodes, and rotifers, as well as the life span of neurospora, 2) inhibit development of some forms of cancer, 3) enhance humoral and cell-mediated immune responses, and 4) slow development of amyloidosis and the autoimmune disorders of NZB mice. Free-radical reactions may also play a significant role in the deterioration of the cardiovascular and central nervous systems with age. It is reasonable to expect, on the basis of present data, that the healthy life span can be increased by five or more years by keeping body weight down, at a level compatible with a sense of well-being, while ingesting diets adequate in essential nutrients but designed to minimize random free-radical reactions in the body.