Masatoshi Mune

Effects of Coffee Consumption on Oxidative Susceptibility of Low-Density Lipoproteins and Serum Lipid Levels in Humans

Since little is known about how coffee intake affects low-density lipoprotein (LDL) oxidative susceptibility and serum lipid levels, we conducted anin vivo study in 11 healthy male students of Wakayama Medical University aged between 20 and 31 years fed an average Japanese diet. On days 1-7 of the study, the subjects drank mineral water. On day 7, the subjects began drinking coffee, 24 g total per day, for one week. This was followed by a one week “washout period” during which mineral water was consumed. Fasting peripheral venous blood samples were taken at the end of each one-week period. LDL oxidation lag time was approximately 8% greater (p < 0.01) after the coffee drinking period than the other periods. Serum levels of total cholesterol and LDL-cholesterol (LDL-C) and malondialdehyde (MDA) as thiobarbituric acid reactive substances (TBARS) were significantly decreased after the coffee drinking period. Finally, regular coffee ingestion may favorably affect cardiovascular risk status by modestly reducing LDL oxidation susceptibility and decreasing LDL-cholesterol and MDA levels.

Effect of vitamin E on lipid metabolism and atherosclerosis in ESRD patients

BACKGROUND Oxidative stress is enhanced in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). Bioincompatibility represents an important source of reactive oxygen species. HD patients exhibit altered anti-oxidative defences and anti-oxidative vitamins such as vitamin E and C are altered in uremia. Frequently, HD patients also suffer from atherosclerotic cardiac disease. We have previously reported that low density lipoprotein (LDL) of HD patients is rich in malondialdehyde (MDA), an end product of lipid peroxidation. MDA rich LDL is thought to be an atherogenic lipoprotein due to its enhancement of macrophage foam cell formation. METHODS We conducted a controlled study for two years comparing the effects of a vitamin E coated cellulose membrane dialyzer and an ordinary cellulose membrane dialyzer on lipid metabolism and the progress of atherosclerosis. LDL-MDA and oxidized LDL (ox-LDL) were measured in HD patients using these two types of dialyzers. Plasma vitamin E and lipid concentrations were also evaluated. The aortic calcification index (ACI) was evaluated by CT scan to assess the progress of atherosclerosis before and for every year after treatment. RESULTS Use of a vitamin E coated cellulose membrane dialyzer for six months, one year and two years resulted in a significant reduction in LDL-MDA and ox-LDL compared to the ordinary cellulose membrane dialyzer. Treatment with a vitamin E-coated dialyzer significantly reduced the percentage increase in ACI after 24 months compared to the control. There were no significant changes in plasma vitamin E and lipid concentrations between the two groups. CONCLUSIONS These results suggest that the oxidative stress could be one of the stimulating factors of abnormal lipid metabolism and atherosclerosis in ESRD patients.

Dietary calorie restriction in the Emory mouse: effects on lifespan, eye lens cataract prevalence and progression, levels of ascorbate, glutathione, glucose, and glycohemoglobin, tail collagen breaktime, DNA and RNA oxidation, skin integrity, fecundity, and cancer

The Emory mouse is the best model for age-related cataract. In this work we compare the effects of feeding a control diet (C) with a diet restricted (R) by 40% relative to C animals. In the R animals, median lifespan was extended by 40%. The proportion of R mice with advanced cataract was lower than C mice as early as 5 months of age. The mean grade of cataract was lower in R animals, beginning at 11 months and continuing until the end of the study. Ascorbate levels in R plasma and liver were 41-56% of C animals. There was no difference between diet groups with respect to lens ascorbate. Aging was associated with a decrease in ascorbate in lenses and kidneys in C and R mice. By 22 months, R animals had 48% higher liver glutathione levels than C mice. Liver glutathione levels were maximal at 12 months. Plasma glucose levels were > 27% lower in R animals at 6.5 and 22 months, and there was a 14% increase in glucose levels upon aging for both diet groups. In R mice, glycohemoglobin levels were 51% lower and tail collagen breaktime was decreased by 40%, even in younger animals. Collagen breaktime increased > 360% upon aging for both diet groups. Rates of production of urinary oxo8dG and oxo8G were higher in R animals compared with C animals, and increased upon aging. C animals exhibited more cancer and dermatological lesions, but less tail tip necrosis and inflamed genitals than R mice. These data allow evaluation of several theories of aging.

Deletion of the kinase domain in death-associated protein kinase attenuates tubular cell apoptosis in renal ischemia-reperfusion injury

Death-associated protein kinase (DAPK) is a calcium/calmodulin-dependent serine/threonine kinase localized to renal tubular epithelial cells. To elucidate the contribution of DAPK activity to apoptosis in renal ischemia-reperfusion (IR) injury, wild-type (WT) mice and DAPK-mutant mice, which express a DAPK deletion mutant that lacks a portion of the kinase domain, were subjected to renal pedicle clamping and reperfusion. After IR, DAPK activity was elevated in WT kidneys but not in mutant kidneys (1785.7 +/- 54.1 pmol/min/mg versus 160.7 +/- 60.6 pmol/min/mg). Furthermore, there were more TUNEL-positive nuclei and activated caspase 3-positive cells in WT kidneys than in mutant kidneys after IR (24.0 +/- 5.9 nuclei or 9.4 +/- 0.6 cells per high-power field [HPF] versus 6.3 +/- 2.2 nuclei or 4.4 +/- 0.7 cells/HPF at 40 h after ischemia). In addition, the increase in p53-positive tubule cells after IR was greater in WT kidney than in mutant kidneys (9.9 +/- 1.4 cells/HPF versus 0.8 +/- 0.4 cells/HPF), which is consistent with the theory that DAPK activity stabilizes p53 protein. Finally, serum creatinine levels after IR were higher in WT mice than in mutant mice (2.54 +/- 0.34 mg/dl versus 0.87 +/- 0.24 mg/dl at 40 h after ischemia). Thus, these results indicate that deletion of the kinase domain from DAPK molecule can attenuate tubular cell apoptosis and renal dysfunction after IR injury.

Effect of environmental changes on oxidative deoxyribonucleic acid (DNA) damage in systemic lupus erythematosus

Abstract In a study conducted in Japan, the authors used urinary 8-hydroxydeoxyguanosine (8-OHdG) to study the effects of high-intensity and low-intensity sunlight on oxidative damage to deoxyribonucleic acid (DNA) in patients who had systemic lupus erythematosus (SLE). During late May through early September (i.e., a period of high-intensity sunlight), the mean urinary 8-OHdG level in SLE patients was significantly higher than in controls (31.0 ± 20.6 [standard deviation] ng/mg vs. 15.4 ± 7.2 ng/mg, respectively [p < .05]). During late November through early March (i.e., low-intensity sunlight season), however, no significant differences were noted (15.4 ± 5.5 ng/mg vs. 16.3 ± 4.6 ng/mg, respectively). The mean urinary 8-OHdG level in SLE patients during the period of high-intensity sunlight was significantly higher than during the period of low-intensity sunlight (21.3 ± 20.6 ng/mg vs. 12.6 ± 6.7 ng/mg, respectively; p < .01), although no such seasonal changes were observed among controls (16.2 ± 8.0 ng/mg vs. 15.7 ± 5.1 ng/mg, respectively). The effect of sunlight intensity (i.e., season) may require consideration when oxidative DNA damage occurs in individuals who have SLE.

Effect of dietary fish oil, vitamin E, and probucol on renal injury in the rat ☆

Dietary fish oil, vitamin E, and probucol have been considered in a variety of human and experimental models of kidney disease. Using subtotal nephrectomized cholesterol-fed rats as a model for progressive kidney disease, we examined the effect of 5% dietary fish oil, or a combination of 5% dietary fish oil with 500 IU vitamin E/kg diet or 1% probucol on renal injury. Three-month-old Sprague Dawley rats were fed a control diet (C group) or a cholesterol supplemented (2%) diet (Ch group) containing either fish oil (FO group) or fish oil plus vitamin E (FO+E group) or fish oil plus probucol (FO+P group). After 4 weeks of dietary treatment, the right kidney was electrocoagulated and the left kidney nephrectomized. After 8 weeks, 24-hour urine was collected before sacrifice. No effect of the dietary treatments was noted on serum creatinine, blood urea nitrogen, or proteinuria, except that proteinuria was highest in FO+P group. Rats receiving the cholesterol diets had higher serum low density lipoprotein (LDL) + very low density lipoprotein (VLDL) cholesterol (P < 0.05). In contrast, rats in the FO+P group had the lowest serum total cholesterol and LDL+VLDL cholesterol among all groups. The FO group had 26% lower kidney alpha-tocopherol concentrations than the C group. However, inclusion of vitamin E in the diet (FO+E group) increased the kidney alpha-tocopherol status to a level comparable to that in the C group, whereas inclusion of probucol in fish oil diet (FO+P group) did not improve the kidney alpha-tocopherol status. Rats fed the cholesterol diet had a 2.5-fold higher glomerular segmental sclerosis (GSS) score and 1.5-fold higher glomerular macrophage (GM) subpopulation than the C group. These effects of the cholesterol diet were ameliorated by a fish oil diet (FO group: GSS by 30%, GM by 24%). The inclusion of vitamin E in the fish oil diet (FO+E group) did not further improve the GSS score or GM subpopulation. However, inclusion of probucol in fish oil diet (FO+P group) lowered the GSS score by 73% and reduced GM subpopulation by 83% compared with the Ch group. These remarkable changes can be attributed to the powerful hypocholesterolemic activity of probucol. Our findings indicate that progression of glomerular sclerosis in the rat remnant kidney model of progressive kidney disease can be significantly modulated with fish oil treatment.

Effect of calorie restriction on liver and kidney glutathione in aging emory mice

Increases in antioxidant defense capacity have been associated with increases in the health and life span of calorie restricted animals. Emory mice develop late-life cataract, a lesion associated with oxidative damage and loss of lens glutathione (GSH). The effect of calorie restriction on GSH in liver and kidney in this model has not been explored. GSH and oxidized GSH (GSSG) were measured by HPLC in liver and kidney of Emory mice fed a control diet (C; 85% calories of ad-lib fed mice) or 60% calorie intake of C (R; 40% calorie restriction relative to C mice) for up to 22 mo age. Liver GSH concentration increased significantly in C and R mice from 4.5 to 12 mo old with no difference observed between the two groups. At 22 mo of age, liver GSH was lower than that of 12 mo old in both groups. As compared with GSH at 12 mo old, this decrease was almost twice as greater in C (70%, p=0.001) than in R mice (36%, p=0.02), so that R mice had a significantly higher concentration of GSH in liver than C mice at 22 mo of age (R = 32.8+5.1, C= 22.1+8.3 imol GSH/g protein, p<0.01). Liver GSSG was similar in C and R mice at 12 mo of age (4.45+1.35 vs. 4.75+1.83 imol GSSG/g protein), but increased in R mice at 22 mo (R=5:43±1.48; C=3.22±1.02, p<0.01). Therefore, at 22 mo old, total liver glutathione (GSH+GSSG) was higher in R than in C mice. There was no significant difference in GSH, GSSG and total GSH in kidney from C and R mice at these ages. Thus, calorie restriction reduces the age-related loss of GSH antioxidant capacity in liver but not kidney of Emory mice.

Effects of antioxidants on kidney disease.

Kidney mesangial cells (MCs) and vascular smooth muscle cells (VSMCs) are closely related in terms of origin, microscopic anatomy, histochemistry, and contractility. This relationship suggests a similarity between kidney glomerular sclerosis and atherosclerosis. Vitamin E appears beneficial in the prevention and treatment of coronary disease and also inhibits the proliferation of VSMCs in vitro. We used vitamin E and probucol to treat glomerular sclerosis and MC-proliferative glomerulonephritis (GN) in two animal models of glomerular disease. Using rats, a remnant kidney model accelerated with hyperlipidemia was employed to reflect progressive glomerular sclerosis leading to chronic renal failure, and an anti-thymocyte serum treatment was used to model acute MC-proliferative GN. Supplemental dietary antioxidants suppress MC proliferation and glomerular sclerosis in models of glomerular disease in rats. These results suggest that treatment with antioxidants may be a promising intervention to prevent progression of kidney disease.

Successful pregnancy and delivery in a case of systemic lupus erythematosus treated with immunoadsorption therapy and cyclosporin A.

A 32-year-old woman diagnosed as systemic lupus erythematosus (SLE) became pregnant. During pregnancy she was treated with a daily dosage of prednisolone 15 mg. However, because the exanthema became worse, she was hospitalized on January 14, 1997 in order to receive immunoadsorption therapy. Before delivery we implemented the immunoadsorption therapy twice and cyclosporin A (CsA) was administered simultaneously. She gave birth in her 37th week. The baby weighed 2260 g at the time of delivery and had no deformities. The mother also had no side effects. The success of pregnancy and childbirth in our case, without any side effects, shows the possibility that the combination of CsA and immunoadsorption therapy may be considered safe to control a pregnancy complicated by SLE.

Severe gustatory disorder caused by cisplatin and etoposide

Abstract A 48-year-old woman with small-cell lung cancer received combined chemotherapy consisting of cisplatin (CDDP) and etoposide (Vp-16). Although the gustatory threshold in the glossopharyngeal nerve area was normal (14 dB) before chemotherapy, it rose to 22 dB on day 8 of chemotherapy, and it could not be measured, because of severe gustatory disorder, from day 15 to day 29. In the chorda tympani nerve area, the threshold was normal until day 15, but it could not be measured on day 29. This gustatory disorder continued for 2 more months, until the time of the patients discharge. Although gustatory disorder caused by anticancer drugs has been reported as a rare side effect, this may be because it has been reported as appetite loss, and it may happen more frequently than reported cases would suggest. As gustatory disorder reduces the patients quality of life, the presence of this side effect should be given more serious consideration.