Application

17.3.1 Oxidative Stress in Newborn Babies

Infants have less protection against oxidation since they have lower levels of antioxidants and antioxidant enzymes than healthy adults.5 In addition, a rapid perfusion of oxygen in infants at birth may cause an increase of oxidative stress since ischemia/reoxygenation is considered as one of the major causes of oxidative stress.6 In fact, infants have higher plasma level of F2-isoprostanes,7 free radical oxidation products of arachidonic acid, than adults. To obtain further evidence of oxidative stress in newborn infants we measured daily change in the redox status of plasma coenzyme Q using above described methods.

Blood was collected with an aliquot of heparin from the umbilical cord vein of infants at time of delivery and at 1, 3, and 5 days of age with parental consent. In this study samples were collected from 20 infants born normally at full term (gestational age was between 37 to 41 weeks) having body weights of 2345 to 3940 g. Nine infants were born with asphyxia (gestational age was from 31 to 41 weeks) having body weights of 1508 to 3352 g with lower than 5 points in their Apgar scores.

In normally born infants, plasma levels of vitamin C ( the most reactive antioxidant in plasma as shown in Figure 17.1) decreased significantly after birth as shown in Figure 17.4A. Infants with asphyxia showed a similar decline in vitamin C levels yet a significant difference remained between the two groups at days 3 and 5.

FIGURE 17.4 Changes in plasma levels of vitamin C (A), total coenzyme Q-10 (total Q-10) (B), and oxidized form of coenzyme Q (CoQ-10) percentage in total Q-10 (%CoQ-10) (C) in normal (B) and asphyxiated (J) infants after birth. *, **, *** indicate significant differences (P< 0.05, 0.01, and 0.001, respectively) compared to values of normal infants at birth; # and ### indicate significant differences (P < 0.05 and 0.001, respectively) compared to the values of infants with asphyxia at birth, as determined by f-test. Italic numbers show P values between normal infants and infants born with asphyxia at the same age, as determined by f-test. NS stands for not significant. From [5] with permission.

FIGURE 17.4 Changes in plasma levels of vitamin C (A), total coenzyme Q-10 (total Q-10) (B), and oxidized form of coenzyme Q (CoQ-10) percentage in total Q-10 (%CoQ-10) (C) in normal (B) and asphyxiated (J) infants after birth. *, **, *** indicate significant differences (P< 0.05, 0.01, and 0.001, respectively) compared to values of normal infants at birth; # and ### indicate significant differences (P < 0.05 and 0.001, respectively) compared to the values of infants with asphyxia at birth, as determined by f-test. Italic numbers show P values between normal infants and infants born with asphyxia at the same age, as determined by f-test. NS stands for not significant. From [5] with permission.

The percentage of the oxidized form of coenzyme Q-10 (%CoQ-10) in total coenzyme Q-10 was found to be in the range of 25 to 32% during the initial 5 days of life and significantly greater than values generally observed in young healthy adults (4.5%), potentially indicating a condition of oxidative stress at birth. In contrast, %CoQ-10 in infants with asphyxia was found to be significantly elevated (39 to 62%) than values associated with infants having a normal birth (Figure 17.4C). While these results indicate that oxidative stress is more evident in infants with asphyxia, it is worth noting that total levels of coenzyme Q-10 in both groups were equivalent (Figure 17.4B) showing that the measurement of %CoQ-10 offers a true indication of redox status.

17.3.2 Oxidative Stress in Patients with Hepatitis, Cirrhosis, and Hepatoma

Human liver cancer often develops after the onset of chronic hepatitis and the subsequent cirrhosis. Measurement of oxidative stress at each stage is of interest since oxidative stress has been suggested as a causative factor in cancer. However, only a limited number of papers have documented the occurrence of oxidative stress in these liver patients. Therefore, we applied the above described method to plasma obtained from patients with hepatitis, cirrhosis, and hepatoma.8

Patients examined in this study were hospitalized at First Department of Medicine in Kyoto Prefectural University of Medicine and were diagnosed with chronic active hepatitis (18 men and 10 women), liver cirrhosis (10 men and 6 women), and hepatocellular carcinoma (15 men and 5 women). All were infected with hepatitis C virus except for 3 patients with hepatitis, 1 with cirrhosis, and 2 with hepatoma who had contracted the hepatitis B virus. The normal subjects consisted of 12 men and 4 women between the ages of 40 and 83 years. Average ages (± S.D.) in the four groups were 59.5 ± 10.7, 60.4 ± 13.0, 65.7 ± 7.0, and 57.7 ± 16.6, respectively, providing no statistical difference.

A significant decrease in plasma ascorbate level was observed in patient groups as compared with normal subjects (data not shown). However, it is also possible that the lowered level of plasma ascorbic acid in these patients was caused by the shortage of ascorbate intake.

We, therefore, adopted a different approach and a newly developed method for the measurement of plasma ubiquinol-10 and ubiquinone-10 was applied. The ratio of ubiquinone-10 to ubiquinol-10 should be one of the most reliable markers of oxidative stress since it is a direct product of redox imbalance. Figure 17.5A shows that patients with chronic active hepatitis, liver cirrhosis, and hepatocellular carcinoma had significantly higher content of plasma ubiquinone-10 expressed as %CoQ-10 = ubiquinone-10/(ubiquinone-10 + ubiquinol-10) than normal subjects. These results indicate that oxidative stress is evident after the onset of hepatitis and the subsequent

FIGURE 17.5 Box and whisker plots of plasma CoQ-10 percentage (%CoQ-10) in total coenzyme Q-10 (A) and ratio of vitamin E to total cholesterol (B) among normal subjects and patients with chronic active hepatitis, liver cirrhosis, and hepatocellular carcinoma (hepatoma). Significant differences compared to normal subjects were analyzed by nonparametric Mann-Whitney test. From [6] with permission.

FIGURE 17.5 Box and whisker plots of plasma CoQ-10 percentage (%CoQ-10) in total coenzyme Q-10 (A) and ratio of vitamin E to total cholesterol (B) among normal subjects and patients with chronic active hepatitis, liver cirrhosis, and hepatocellular carcinoma (hepatoma). Significant differences compared to normal subjects were analyzed by nonparametric Mann-Whitney test. From [6] with permission.

cirrhosis and liver cancer. A significant increase in the ratio of plasma ubiquinol-9 to ubiquinone-9 was also observed in LEC rat after the onset of hepatitis.9 On the other hand, vitamin E/total cholesterol ratio remained unchanged among four groups as shown in Figure 17.4B as expected from Figure 17.1.

Getting Back Into Shape After The Pregnancy

Getting Back Into Shape After The Pregnancy

Once your pregnancy is over and done with, your baby is happily in your arms, and youre headed back home from the hospital, youll begin to realize that things have only just begun. Over the next few days, weeks, and months, youre going to increasingly notice that your entire life has changed in more ways than you could ever imagine.

Get My Free Ebook


Post a comment