[Effects of copper supplementation on lipid profiles in elderly patients with copper deficiency].

AIM: The purpose of this study was to examine the effects of copper supplementation on lipid profiles in elderly patients with copper deficiency. METHODS: Nine long-term bed-ridden, patients (5 men and 4 women, mean age 83.3+/-8.7 years old) with severe copper deficiency, who had a serum copper of 15 microg/dL or less (normal range 70-140 microg/dL), had their diets supplemented with copper sulfate (3 mg/day) over 12 weeks in addition to their diet of only one kind of enteral food with a low concentration of copper. Copper, ceruloplasmin, total cholesterol (TC), triacylglycerides (TG), HDL-cholesterol (HDL-C), c-reactive protein (CRP), creatinine (Cr), zinc (Zn) and albumin (Alb) in the serum were measured before, 4 weeks and 12 weeks after copper supplementation. RESULTS: Serum copper and ceruloplasmin were significantly increased at 4 weeks after copper supplementation. TG was significantly increased at 4 weeks after copper supplementation, but at 12 weeks the increase of TG was not significant. TC, HDL-C, CRP, Cr, Zn and Alb were not changed by copper supplementation. CONCLUSION: TG was transiently increased by copper supplementation in elderly patients with copper deficiency. TC and HDL-C were not changed by copper supplementation.

In long-term bedridden elderly patients with dietary copper deficiency, biochemical markers of bone resorption are increased with copper supplementation during 12 weeks.

BACKGROUND: Although the effect of copper on bone has been tested in animals and healthy subjects, no studies concerning the effect of copper supplementation on bone metabolism in patients with copper deficiency have been reported because of the rarity of these patients. This study was conducted to investigate the effect of copper supplementation on bone metabolism in copper-deficient patients. METHOD: This study included 10 patients (83.7 +/- 8.3 years) with dietary copper deficiency under long-term bed rest for more than 12 months. They had their diets supplemented with copper sulfate (3 mg/day) over 12 weeks in addition to their diet of only one kind of enteral food with a low concentration of copper. Serum copper and ceruloplasmin, urinary deoxypyridinoline (DPD) and collagen-type 1 N-telopeptide (NTX) (biomarkers of bone resorption), serum osteocalcin (OC) and bone-specific alkaline phosphatase (Bone ALP) (biomarkers of bone formation) were analyzed at baseline, 4 and 12 weeks after copper supplementation. RESULTS: DPD and NTX excretion were significantly increased 4 weeks after copper supplementation (p = 0.009 and p = 0.013, respectively). Serum bone ALP and OC were not significantly changed 12 weeks after copper supplementation (p = 0.051 and p = 0.594). CONCLUSIONS: In patients with nutritional copper deficiency, bone resorption markers are increased with copper supplementation.

[Relationships among urine pH, serum uric acid and pyuria in hospitalized elderly patients].

To identify risk factors of urinary tract infection (UTI) in geriatric patients, the levels of serum uric acid, serum creatinine, and urine pH were compared between pyuria-positive and -negative patients in a geriatric ward. The level of serum uric acid was higher with lower urine pH level in the pyuria-negative patients than in positive patients. The level of serum creatinine was relatively higher in the pyuria-negative patients than in the positive patients. Even after matching for serum creatinine, serum uric acid was significantly higher in the pyuria-negative male patients. The results in the present study proposed an interesting hypothesis about backgrounds for UTI in geriatric patients. The relationships among serum uric acid, serum creatinine, urine pH, and pyuria should be examined further in a larger population and in experimental studies.

Detection of prepro-ET-1 mRNA in normal rat kidney by in situ RT-PCR.

BACKGROUND: Available evidence has shown that endothelin-1 (ET-1) acts in an autocrine/paracrine fashion rather than as a hormone or cytokine. Therefore, the analysis of local ET-1 production is a crucial step toward understanding its physiological and pathophysiological importance. In this study, in situ RT-PCR was utilized to detect tubular expression of prepro-ET-1 mRNA in normal rat kidney. METHODS: Kidneys were taken from normal Sprague-Dawley rats weighing approximately 200 g. In situ RT-PCR was carried out using the preparations embedded in paraffin and cut at a thickness of 8 microm. Furthermore, we tried semiquantitation of the prepro-ET-1 mRNA expression along different nephron segments by densitometric analysis. RESULTS: Prepro-ET-1 mRNA expression was detected in all tubular segments of the kidney from normal rats. Densitometric analysis demonstrated its highest expression in cortical collecting duct (CCD) and outer medullary collecting duct (OMCD). The expression was the lowest in thin descending limb of Henle's loop (TDL). CONCLUSION: This study showed that all tubular segments have the ability to synthesize ET-1 in rat kidney. It would be worth evaluating the levels prepro-ET-1 mRNA expression in various diseases by in situ RT-PCR to understand its pathophysiological role in such settings.

Dietary Zn deficiency does not influence systemic blood pressure and vascular nitric oxide signaling in normotensive rats.

Because zinc (Zn) is an important component for cell protection against certain oxygen species, it has been suggested that Zn deficiency impairs the potent oxidant defense capacity, which is constitutively provided in the vascular system. However, the influence of dietary Zn deficiency on systemic blood pressure and vascular system is controversial and unclear. We therefore examine the effect of dietary Zn deficiency on systemic blood pressure, a potent superoxide scavenger, aortic Cu/Zn superoxide dismutase (SOD) activity, a most representative synthase of the endothelium-derived relaxing factor, and aortic endothelial nitric oxide synthase (eNOS) expression. Furthermore, the direct effects of intravenous administration of NOS inhibitor, Nomega-nitro-L-arginine methyl ester (LNAME), and a SOD mimetic compound, tempol, in normotensives were tested in Wistar-Kyoto (WKY) rats. A Zn-deficient diet (4 wk) contributed to growth retardation, the decrease in thymus weight, and the lower levels of serum Zn compared with the standard diet group. However, no significant difference in conscious systolic and diastolic blood pressure was found in the Zn-deficiency group. The administration of L-NAME caused an increase in the mean arterial pressure (MAP) levels in the two groups of rats and the involvement of the vasodilator nitric oxide (NO) in the regulation of systemic BP in the normotensive state. On the other hand, administration of the superoxide scavenger, tempol, led to a decrease in MAP levels in the two groups of rats, indicating the participation of the oxygen free radical, superoxide, in the maintenance of the systemic BP in a normotensive state. There were no significant differences between the Zn-deficient diet group and the standard diet group in the normotensive state. eNOS expression and Cu/Zn SOD activity in the aorta were also intact in Zn-deficient normotensive rats. These findings suggest that the 4 wk of Zn deficiency was inadequate to alter systemic blood pressure and focal NO signaling in the normotensive state. Long-term Zn deficiency affects the neuronal, immune, and hematopoietic systems, which contribute to systemic and/or local circulation. However, Zn deficiency alone does not cause hypertension and local vascular dysfunction in the normotensive state.

ACE inhibition increases expression of the ETB receptor in kidneys of mice with unilateral obstruction.

Unilateral ureteral obstruction (UUO) is a well-established model for the study of interstitial fibrosis in the kidney. It has been shown that the renin-angiotensin system plays a central role in the progression of interstitial fibrosis. Recent studies indicate that endothelin, a powerful vasoconstrictive peptide, may play an important role in some types of renal disease. To investigate the effects of angiotensin II on endothelin and its receptors in the kidney, mice were subjected to UUO and treated with or without enalapril, an orally active angiotensin-converting enzyme inhibitor, in their drinking water (100 mg/l). The animals were killed 5 days later. Using RT coupled with PCR, we measured the levels of endothelin-1, endothelin A, and endothelin B (ET(B)) along with transforming growth factor-beta, TNF-alpha, and collagen type IV mRNA expression in the kidney with UUO and the contralateral kidney along with interstitial expansion in the kidney cortex by a standard point counting method. We found that enalapril administration ameliorated the increased expression of ET-1 mRNA in the obstructed kidney by 44% (P < 0.02). Although the level of endothelin A mRNA expression was significantly increased in the obstructed kidney, it was not affected by enalapril. We found that enalapril treatment increased ET(B) mRNA expression by 115% (P < 0.05) and protein expression (measured by Western blot) in the kidney with an obstructed ureter. Enalapril treatment alone inhibited the expansion of interstitial volume due to UUO by 52%. Cotreatment with enalapril and the ET(B) receptor antagonist BQ-788 inhibited the expression of interstitial volume by only 19%. This study confirms that enalapril inhibits the interstitial fibrosis in UUO kidneys. It also suggests a beneficial and unforeseen effect of enalapril on the obstructed kidney by potentially stimulating the production of nitric oxide through an increased expression of the ET(B) receptor.

Decreased expression of brain nitric oxide synthase in macula densa cells and glomerular epithelial cells of rats with mercury chloride-induced acute renal failure.

To elucidate the mechanisms responsible for the development of HgCl(2)-induced acute renal failure (ARF), we examined the expression of brain type (b) nitric oxide synthase (NOS), which is involved in the generation of the vasodilator nitric oxide (NO), in the renal cortex of rats at 20 h after exposure to 7.5 mg/kg HgCl(2). Both blood urea nitrogen and serum creatinine were significantly increased in rats exposed to HgCl(2) relative to control rats, indicating the induction of ARF resulting from HgCl(2) exposure. Histopathological analysis demonstrated that, in addition to necrosis of proximal tubule epithelial cells, necrosis of macula densa cells and swelling of glomerular epithelial cells were observed in the renal cortex of rats with HgCl(2)-induced ARF. Consequently, the number of pars maculata segments was decreased by 42% in rats with HgCl(2)-induced ARF compared to control rats. The primary sites of bNOS mRNA and protein expression were macula densa cells and glomerular epithelial cells in the renal cortex of control rats and rats with HgCl(2)-induced ARF. The abundance of the bNOS mRNA and protein was significantly decreased in rats with HgCl(2)-induced ARF relative to control rats. These observations suggest that the production of the vasodilator NO derived from bNOS is decreased at the glomerulus level in the HgCl(2)-induced ARF setting. Thus, the reduction in bNOS expression may in part contribute to the progression of HgCl(2)-induced ARF through the deterioration of glomerular hemodynamics. In addition, the decrease in bNOS expression may be primarily the result of cell injury caused by the cytotoxic effect of HgCl(2).

Transforming growth factor-beta induces renal epithelial jagged-1 expression in fibrotic disease.

For elucidation of the mechanisms by which growth factors and cytokines affect renal epithelial cells, gene array analysis of renal cells cultured in the presence of transforming growth factor-beta1 (TGF-beta1) was performed. Many genes that were not previously considered to be involved in renal cell biologic processes were affected, one of which was jagged-1. The jagged ligand/notch receptor family controls the formation of boundaries between groups of cells and regulates cell fates. On the basis of the array analysis, jagged-1 expression was further evaluated in cultured cells and in C57BL/6 mice with a model of unilateral ureteral obstruction (UUO). Recombinant human TGF-beta1 increased jagged-1 mRNA levels at concentrations between 10(-11) and 10(-10) M. There was a commensurate increase in jagged-1 protein levels, as assessed by Western blotting. The expression of jagged-1 mRNA and protein was observed to be significantly increased in the kidneys of C57BL/6 mice with obstructed ureters, compared with the contralateral kidneys, at 7 and 14 d of UUO. Immunohistochemical analyses demonstrated jagged-1 expression in distal tubules of kidneys from normal mice or contralateral kidneys from mice with UUO. Jagged-1 protein expression was increased in tubules not yet in apparent atrophy in the kidneys with an obstructed ureter. Jagged-1 expression was significantly increased in the kidneys of normal mice treated with TGF-beta1 and was decreased in the kidneys of mice with UUO treated with a TGF-beta receptor II-Fc chimera. These results suggest that jagged-1 is expressed in normal kidneys and that this expression is upregulated during renal disease, in a TGF-beta-dependent manner.