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Familial hypercholesterolemia (FH) is a highly prevalent autosomal dominant hereditary disease, generally characterized by three major signs, hyper-low-density-lipoprotein (LDL) cholesterolemia, tendon/skin xanthomas and premature coronary artery disease (CAD). Because the risk of CAD is very high in these patients, they should be identified at an early stage of their lives and started on intensive treatment to control LDL-cholesterol. We here introduce a new guideline for the management of FH patients in Japan intending to achieve better control to prevent CAD. Diagnostic criteria for heterozygous FH are 2 or more of 1) LDL-cholesterol ≥ 180 mg/dL, 2) tendon/skin xanthoma(s), and 3) family history of FH or premature CAD within second degree relatives, for adults; and to have both 1) LDL-cholesterol ≥ 140 mg/dL and 2) family history of FH or premature CAD within second degree relatives, for children. For the treatment of adult heterozygous FH, intensive lipid control with statins and other drugs is necessary. Other risks of CAD, such as smoking, diabetes mellitus, hypertension etc., should also be controlled strictly. Atherosclerosis in coronary, carotid, or peripheral arteries, the aorta and aortic valve should be screened periodically. FH in children, pregnant women, and women who wish to bear a child should be referred to specialists. For homozygotes and severe heterozygotes resistant to drug therapies, LDL apheresis should be performed. The treatment cost of homozygous FH is authorized to be covered under the program of Research on Measures against Intractable Diseases by the Japanese Ministry of Health, Labour, and Welfare.

Our objective was to evaluate the maternal-fetal transfer of melatonin in pregnant women. Serum melatonin concentration was measured by high-performance liquid chromatography with electrochemical detection in a maternal vein and in the umbilical artery and umbilical vein at the time of birth. Blood samples were obtained from 12 women who had spontaneously delivered vaginally at night. A single oral dose of melatonin was administered to each of 33 patients who underwent a cesarean section, and, blood samples were taken at 1, 2, 3, or 4 hr after the administration of melatonin at delivery. Cesarean section was performed between 1300 and 1500 hr. The mean melatonin concentrations of melatonin in maternal peripheral venous blood and umbilical arterial and umbilical venous blood did not differ significantly, and positive correlations in the serum levels of melatonin were observed between the three sources of blood. The oral administration of 3 mg of melatonin to pregnant women led to marked increases in the serum levels of melatonin, with maximum levels observed 2 hr (21.84 +/- 2.09 ng/ml) after drug administration. Changes in serum levels of melatonin in the umbilical vein and artery resembled those found in the maternal vein. Serum melatonin concentrations did not differ significantly between the maternal vein and the umbilical veins. Serum levels of melatonin in the umbilical vein after the administration of melatonin were significantly and closely correlated with those in the maternal vein (r = 0.924, P < 0.001). These results suggest that, in humans, melatonin is transferred from the maternal to the fetal circulation both easily and rapidly. A potential for the therapeutic use of melatonin as an antioxidant exists in the patients with preeclampsia.

Melatonin is a powerful scavenger of oxygen free radicals. In humans, melatonin is rapidly transferred from the maternal to the fetal circulation. To investigate whether or not maternal melatonin administration can protect the fetal rat brain from radical-induced damage by increasing the activities of antioxidant enzymes, we administered melatonin to pregnant rats on day 20 of gestation. Melatonin (10 mg/kg) was injected intraperitoneally at daytime (14:00 hr) and, to remove the fetuses, a laparotomy was performed at 1, 2, or 3 hr after its administration. We measured the melatonin concentration in the maternal serum and in fetal brain homogenates and determined the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in fetal brain homogenates. Melatonin administration markedly increased melatonin concentrations in the maternal serum and fetal brain homogenates, with peak levels achieved 1 hr after melatonin administration (serum: 538.2+/-160.7 pM/mL; brain homogenates: 13.8+/-2.8 pM/mg protein). Between 1 and 3 hr after melatonin administration, GSH-Px activity in fetal brain homogenates increased significantly (P<0.01). Similarly, SOD activity increased significantly between 1 and 2 hr after melatonin administration (P<0.01). These results indicate that melatonin administration to the mother increases antioxidant enzyme activities in the fetal brain and may thereby provide indirect protection against free radical injury. Thus, melatonin may potentially be useful in the treatment of neurodegenerative conditions that may involve excessive free radical production, such as fetal hypoxia and preeclampsia.

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