Oxidative Status in Chronic Hepatitis C: The Influence of Antiviral Therapy and Prognostic Value of Serum Hydroperoxide Assay

The effect of α-interferon (α-IFN) and ribavirin (RBV) treatment on oxidative status in chronic hepatitis C (CHC) is unknown.

Aim: To study the time course of oxidative status in patients with CHC during α-IFN and RBV administration, and to evaluate the role of oxidative status in order to predict the therapeutic response.

Patients and methods: Fifty one patients with CHC were studied. All received a combination of α-IFN and RBV for 6 or 12 months in relation to the type of response. The hydroperoxides concentration in serum test samples by D-ROM test was measured in all of the patients before therapy. In 27 patients, hydroperoxides were also measured during the treatment and during the 12 subsequent months.

Results: Cross-sectional analysis demonstrates that patients with a successive long-term response had a lower basal serum hydroperoxide concentration than non-responders (280±40.8 vs 337±83 CARR Units, p<0.05). This resulted to be an independent factor predictive of long-term response in the multi-varied analysis. Longitudinal observation on 27 patients showed that the mean hydroperoxide concentration decreased significantly during treatment (T⁰ 329±79.2 vs T¹² 272±34.5 CARR Units) and that the decrease in the mean values was mainly due to variations in the relapsers group.

Conclusions: Normal basal hydroperoxide concentration helps to predict long-term response to combination therapy. The D-ROM test may be used for screening patients before treatment.     

Lipid peroxidation and total antioxidant status in patients with breast cancer

Oxidative stress is considered to be involved in the pathophysiology of all cancers. The aim of this study is to examine oxidative stress and antioxidant status in patients with breast cancer by evaluation of the serum levels of total antioxidant capacity (TAC) and lipid peroxidation products as malondialdehyde (MDA) and lipid hydroperoxide and to investigate the relationship between these parameters, oxidative stress and serum lipids and lipoproteins. In our study, serum TAC, MDA, lipid hydroperoxide, HDL-cholesterol, VLDL-cholesterol, LDL-cholesterol, total cholesterol, triacylglycerol (TAG), albumin and uric acid levels of 56-breast cancer patients in different clinical stages and 18 healthy women were determined. Significantly lower-levels of TAC were detected in patients with breast cancer in comparison to controls (2.01 +/- 0.01 mmol/l and 2.07 +/- 0.03 mmol/l, respectively, p < 0.05). Serum MDA levels of the patients were higher compared to the controls (3.64 +/- 0.25 microM and 2.72 +/- 0.22 microM, respectively, p < 0.05). No significant difference between lipid hydroperoxide levels of patients and controls was found (0.33 +/- 0.05 microM and 0.32 +/- 0.01 microM, respectively, p > 0.05). These data show that lower TAC and higher MDA levels i.e. increased oxidative stress may be related to breast cancer.     

Effect of hemodialysis on the antioxidative properties of serum

In patients with chronic renal failure undergoing regular hemodialysis (HD), oxidative stress is involved in the development of dialysis-related pathologies. The aim of the study was to measure the effect of HD treatment on the general antioxidative status of serum with special consideration of the specific oxidizability of lipids and proteins. Indicators for the oxidative/antioxidative status of plasma were monitored at the beginning and at the end of a dialysis session on the arterial and venous side of the dialyzer. A decrease in the antioxidant status was accompanied by an increased oxidizability of proteins as well as lipids during HD treatment. During the first passage of the dialyzer, the lag time of lipid oxidation decreased from 114.0+/-19.8 to 81.5+/-18.9 min, the lag time of protein oxidation decreased from 105.0+/-24.6 to 72.9+/-21.3 min and the total antioxidative status decreased from 518+/-24 to 252+/-124 microM trolox equivalents. The carbonyl content of serum proteins was high in patients with end stage renal disease (ESRD) (3.9+/-1.1 vs. 0.9+/-0.1 nmol/mg in controls) but did not change significantly during dialysis procedure. Our data demonstrate that the susceptibility of serum lipids and proteins to oxidative modification is severely increased by HD treatment.     

Effect of exogenous antioxidants on erythrocyte redox status and hepcidin content in disorders of iron metabolism regulation

In many diseases associated with impairments in iron metabolism, erythrocytes exhibit an increased sensitivity to oxidative stress induced in vitro. In this study we have examined the antioxidant status of erythrocytes from healthy donors and from 12 patients with disorders of iron homeostasis by measuring the extent of hemolysis induced in vitro by tert-butyl hydroperoxide (t-BHP). The extent of hemolysis observed with patient erythrocytes was significantly higher than that observed in experiments with erythrocytes from healthy donors. After therapeutic infusions of the antioxidants mexidol or emoxypin, oxidative hemolysis in patients was restored to normal values and blood hepcidin increased significantly as compared with its initial level. A significant correlation was observed between hepcidin concentration after treatment and t-BHP-induced hemolysis before treatment. These data suggest that antioxidants may exert a favorable effect on those at risk for iron overload disease.     

Antenatal glucocorticoids reset the level of baseline and hypoxemia-induced pituitary-adrenal activity in the sheep fetus during late gestation

This study examined the effects of dexamethasone treatment on basal hypothalamo-pituitary-adrenal (HPA) axis function and HPA responses to subsequent acute hypoxemia in the ovine fetus during late gestation. Between 117 and 120 days (term: approximately 145 days), 12 fetal sheep and their mothers were catheterized under halothane anesthesia. From 124 days, 6 fetuses were continuously infused intravenously with dexamethasone (1.80 +/- 0.15 microg.kg(-1).h(-1) in 0.9% saline at 0.5 ml/h) for 48 h, while the remaining 6 fetuses received saline at the same rate. Two days after infusion, when dexamethasone had cleared from the fetal circulation, acute hypoxemia was induced in both groups for 1 h by reducing the maternal fraction of inspired O2. Fetal dexamethasone treatment transiently lowered fetal basal plasma cortisol, but not ACTH, concentrations. However, 2 days after treatment, fetal basal plasma cortisol concentration was elevated without changes in basal ACTH concentration. Despite elevated basal plasma cortisol concentration, the ACTH response to acute hypoxemia was enhanced, and the increment in plasma cortisol levels was maintained, in dexamethasone-treated fetuses. Correlation of fetal plasma ACTH and cortisol concentrations indicated enhanced cortisol output without a change in adrenocortical sensitivity. The enhancements in basal cortisol concentration and the HPA axis responses to acute hypoxemia after dexamethasone treatment were associated with reductions in pituitary and adrenal glucocorticoid receptor mRNA contents, which persisted at 3-4 days after the end of treatment. These data show that prenatal glucocorticoids alter the basal set point of the HPA axis and enhance HPA axis responses to acute stress in the ovine fetus during late gestation.     

The combination therapy with bromocriptine and cyproheptadine in patients with acromegaly

The therapeutic efficacy of the combination of cyproheptadine and bromocriptine was studied in 15 patients with active acromegaly showing incomplete GH suppression in response to bromocriptine therapy alone. The mean basal plasma GH was 31.3 +/- 5.5 micrograms/L, and it decreased to 19.0 +/- 3.9 micrograms/L during the single bromocriptine therapy (10 to 20 mg for 2 to 21 months). When cyproheptadine (12 to 16 mg for 8 to 52 months) was added to bromocriptine therapy, plasma GH decreased further (9.4 +/- 3.0 micrograms/L: vs pretreatment, P less than 0.001; vs bromocriptine treatment, P less than 0.005), and GH normalization was obtained in 8 patients. The plasma somatomedin-C levels in these 8 patients (0.3-1.8 U/ml) were within the normal range during the combination therapy. Plasma GH responses to TRH or GHRH were markedly suppressed in 6 patients during the combination therapy compared to pretreatment or during bromocriptine treatment. In addition, a clear reduction in the tumor size was observed in 4 of 7 previously untreated patients during the combination therapy. In conclusion, cyproheptadine has therapeutic efficacy in acromegalic patients who showed incomplete GH suppression in response to treatment with bromocriptine alone. Following the cyproheptadine and bromocriptine combination therapy tumor shrinkage was observed in some patients.     

Tyrosine phosphorylation of clathrin heavy chain under oxidative stress

In mouse pancreatic insulin-producing betaTC cells, oxidative stress due to H(2)O(2) causes tyrosine phosphorylation in various proteins. To identify proteins bearing phosphotyrosine under stress, the proteins were affinity purified using an anti-phosphotyrosine antibody-conjugated agarose column. A protein of 180kDa was identified as clathrin heavy chain (CHC) by electrophoresis and mass spectrometry. Immunoprecipitated CHC showed tyrosine phosphorylation upon H(2)O(2) treatment and the phosphorylation was suppressed by the Src kinase inhibitor, PP2. The phosphorylation status of CHC affected the intracellular localization of CHC and the clathrin-dependent endocytosis of transferrin under oxidative stress. In conclusion, CHC is a protein that is phosphorylated at tyrosine by H(2)O(2) and this phosphorylation status is implicated in the intracellular localization and functions of CHC under oxidative stress. The present study demonstrates that oxidative stress affects intracellular vesicular trafficking via the alteration of clathrin-dependent vesicular trafficking.     

Hydroperoxide-initiated chemiluminescence: an assay for oxidative stress in biopsies of heart, liver, and muscle.

Hydroperoxide-initiated chemiluminescence was standardized as a microassay to evaluate the occurrence of oxidative stress in human biopsies. Samples of 10 to 50 mg of rat liver or heart were homogenized, diluted in reaction medium, added with tert-butyl hydroperoxide, and assayed for chemiluminescence in a liquid scintillation counter in the out-of-coincidence mode. Optimal conditions for the assay were: 0.3 to 1.2 mg/mL of homogenate protein in 120 mM KCl, 30 mM phosphate buffer (pH 7.4), and 3 mM tert-butyl hydroperoxide at 30 degrees C. In these conditions, maximal chemiluminescence values were 550 +/- 30 and 1100 +/- 40 cps/mg protein, for liver and heart homogenates, respectively. Liver and heart homogenates were subjected to in vitro oxidative stresses such as supplementation with organic hydroperoxide or with enzymatic systems generating superoxide anion or hydrogen peroxide. Chemiluminescence was higher in the poststress samples than in the control ones. The ratio: poststress chemiluminescence/control chemiluminescence (B/A) was about 1.4 or higher for both tissues. Human heart biopsies were utilized to investigate the occurrence of oxidative stress after clinical situations associated to ischemia-reperfusion. B/A ratios were 2.1 +/- 0.4, 1.4 +/- 0.1, and 2.8 +/- 0.4 for human heart, liver, and skeletal muscle, respectively.     

Effect of chronic home care on admission to institutions providing long-term care.

Home care programs are operating throughout Ontario. In October 1975 pilot-test chronic home care (CHC) programs were added in three areas. Whether the Kingston CHC program prevented or delayed admission to an institution providing long-term care was studied in the 218 patients admitted to the program up to mid-March 1976. Forms were completed for all 218 patients admitted, for the 109 still in the program 6 months later, and for the 131 who had left the program by August 1976. Of the 218 patients 20% had applied for admission to an institution providing long-term care before applying for CHC, and another 22% had seriously considered applying to such an institution. The CHC staff judged that 61% would have needed institutional care without CHC. Only 12% of the 218 patients left the CHC program to enter an institution, only 1 of the 48 patients discharged to self-care at home was considering a move to an institution, and only 2 receiving CHC for 6 months applied to an institution during that time. CHC therefore seems to delay greatly admission to an institution providing long-term care for a substantial group of patients.     

Identification of treatment efficacy-related host factors in chronic hepatitis C by ProteinChip serum analysis

Recent development of proteomic array technology, including protein profiling coupling ProteinChip array with surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF/MS), provides a potentially powerful tool for discovery of new biomarkers by comparison of its profiles according to patient phenotypes. We used this approach to identify the host factors associated with treatment response in patients with chronic hepatitis C (CHC) receiving a 48-wk course of pegylated interferon (PEG-IFN) alpha 2b plus ribavirin (RBV). Protein profiles of pretreatment serum samples from 32 patients with genotype 1b and high viral load were conducted by SELDI-TOF/MS by using the three different ProteinChip arrays (CM10, Q10, IMAC30). Proteins showed significantly different peak intensities between sustained virological responders (SVRs), and non-SVRs were identified by chromatography, SDS-PAGE, TOF/MS and tandem mass spectrometry (MS/MS) assay. Eleven peak intensities were significantly different between SVRs and non-SVRs. The three SVR-increased peaks could be identified as two apolipoprotein (Apo) fragments and albumin and, among the eight non-SVR-increased proteins, four peaks identified as two iron-related and two fibrogenesis-related protein fragments, respectively. Multivariate analysis showed that the serum ferritin and three peak intensity values (Apo A1, hemopexin and transferrin) were independent variables associated with SVRs, and the area under the receiver operating characteristic (ROC) curves for SVR prediction by using the Apo A1/hemopexin and hemopexin/transferrin were 0.964 and 0.936. In conclusion, pretreatment serum protein profiling by SELDI-TOF/MS is variable for identification of response-related host factors, which are useful for treatment efficacy prediction in CHC receiving PEG-IFN plus RBV. Our data also may help us understand the mechanism for treatment resistance and development of more effective antiviral therapy targeted toward the modulation of lipogenesis or iron homeostasis in CHC patients.     

The effects of hydrogen peroxide promoted by homocysteine and inherited catalase deficiency on human hypocatalasemic patients

Elevated plasma homocysteine can generate oxygen free radicals and hydrogen peroxide. The enzyme catalase is involved in the protection against hydrogen peroxide. We examined the effect of oxidative stress promoted by homocysteine on erythrocyte metabolism (blood hemoglobin, MCV, folate, B12, serum LDH, LDH isoenzymes, haptoglobin) in the oxidative stress sensitive Hungarian patients with inherited catalase deficiency. The plasma homocysteine (HPLC method, Bio-Rad), folate, B12 (capture binding assay, Abbott), blood hemoglobin concentrations, blood catalase activity (spectrophotometric assay of hydrogen peroxide), and MCV values were determined in 7 hypocatalasemic families including hypocatalasemic (male:12, female:18) patients and their results were compared to those of the normocatalasemic (male:17 female: 12) family members. We found decreased (p <.036) folate (ng/ml) concentrations (male hypocatalasemic 5.44 +/- 2.81 vs. normocatalasemic 7.56 +/- 1.97, female 5.01 +/- 1.93 vs. 6.61 +/- 1.91), blood hemoglobin (p <.010, male:140.2 +/- 11.0 vs. 153.6 +/- 11.6 g/l, female: 128.4 +/- 10.9 vs. 139.6 +/- 9.2 g/l). Increased levels of MCV (p <.001) were detected in hypocatalasemic patients (male: 98.6 +/- 3.4 vs. 90.1 +/- 7.5 fl, female: 95.9 +/- 3.9 vs. 90.1 +/- 2.5 fl), plasma homocysteine (p <.049, male: 9.72 +/- 3.61 vs. 7.36 +/- 2.10 umol/l, female: 9.06 +/- 3.10 vs. 6.84 +/- 2.50 umol/l) and not significant (p >.401) plasma B12 (male: 336 +/- 108 vs. 307 +/- 76 pg/ml, female: 373 +/- 180 vs. 342 +/- 75 pg/ml). The serum markers of hemolysis (LDH, LDH isoenzymes, haptoglobin) did not show significant (p >.228) signs of oxidative erythrocyte damage. We report firstly on increased plasma homocysteine concentrations in inherited catalase deficiency. The increased plasma homocysteine and inherited catalase deficiency together could promote oxidative stress via hydrogen peroxide. The patients with inherited catalase deficiency are more sensitive to oxidative stress of hydrogen peroxide than the normocatalasemic family members. This oxidative stress might be responsible for the decreased concentration of the blood hemoglobin via the oxidation sensitive folate and may contribute to the early development of arteriosclerosis and diabetes in these patients.     

Maternal insulin and placental 3-O-methyl glucose transport

The effects of insulin in the maternal circulation on the placental clearance of 3-O-methyl glucose were investigated in 7 animals in the presence of a constant maternal glucose concentration. While maternal insulin concentration changed from 12 +/- 4 to 175 +/- 33 mu Units/ml, the placental clearance remained constant at 16.2 +/- 1.2 (control) and 15 +/- 1.3 ml/min per kg fetus under the influence of the insulin. To test the secondary hypothesis that in the control condition the hexose transport system was saturated, we performed a further series of experiments in 6 fasted animals. In these animals the control maternal plasma insulin concentration was 2 +/- 0.3 mu Units/ml and after the infusion of insulin it increased to 562 +/- 26 mu Units/ml. Under conditions of constant maternal and fetal plasma glucose concentrations, this massive elevation of plasma insulin did not change the placental clearance of 3MeG which was 15.2 +/- 1.6 in the control condition and 13.3 +/- ml/min per kg under the influence of high insulin. We conclude that maternal insulin ranging from 2 mu Units/ml to supraphysiologic doses does not effect a physiologically significant change in placental hexose transfer. Placental glucose transfer can probably therefore, be changed only be changing the concentration of glucose in the maternal and fetal plasma.     

Plasma phosphatidylcholine hydroperoxide as a new marker of oxidative stress in alcoholic patients

Quantitative analysis of plasma phosphatidylcholine hydroperoxide (PCOOH) is an important step in evaluating the biochemical processes leading to oxidative injury. However, secondary products of lipid peroxidation are now used as indices. One hundred nine alcoholic patients, aged 22-81 years (mean +/- SEM, 52.0 +/- 1.3 years), and 21 healthy volunteers, aged 41-79 years (51.2 +/- 2.2 years), participated in this study. Plasma PCOOH was measured by HPLC with chemiluminescence detection. Plasma PCOOH concentration was significantly higher in alcoholic patients (46.1 +/- 4.1 pmol/ml) than in controls (15.6 +/- 1.8 pmol/ml). It was significantly higher in patients with blood alcohol (88.0 +/- 10.5 pmol/ml) than in those without alcohol (32.6 +/- 3.1 pmol/ml). The patients with high levels of aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase (gamma-GTP), and triglyceride (TG) showed significantly higher PCOOH concentrations than did patients with normal levels. The PCOOH level was positively correlated with levels of gamma-GTP, HDL, blood alcohol concentration, and TG. Plasma PCOOH levels in 29 alcoholic patients after a 6 week abstinence were decreased significantly (22.8 +/- 11.1 pmol/ml), which was associated with improvement on liver function tests. This is the first measurement of plasma PCOOH in alcoholic patients. These results suggest the involvement of lipid peroxidation in alcohol-induced liver damage and confirm that the PCOOH plasma concentration is a new marker of alcohol consumption as well as oxidative stress in alcoholic patients.     

The effect of exercise training on oxidative damage of lipids, proteins, and DNA in rat skeletal muscle: evidence for beneficial outcomes.

Moderate daily exercise is known to be beneficial to health, reducing risks of a number of age-related disorders. Molecular mechanisms that bring about these effects are not clear. In contrast, it has been claimed that some types of prolonged physical exertion are detrimental to health because active oxygen species are generated excessively by enhanced oxygen consumption. Using two age groups of rats, young (4 week) and middle aged (14 months), we investigated the effects of long-term swimming training on the oxidative status of phospholipids, proteins, and DNA. The concentration of thiobarbituric acid reactive substances and 4-hydroxynonenal protein adducts did not differ in the gastrocnemius muscle between exercised and nonexercised animals in the two age groups. The extent of carbonylation in a protein of molecular weight around 29 KDa and the amount of 8-hydroxydeoxyguanosine in nuclear DNA were smaller (p<.05) in the exercised rats than in the sedentary animals. Activities of DT-diaphorase (C1: 29.3+/-1.9; C2: 36.1+/-2.6; E1: 27.2+/-1.3; C2: 33.4+/-2.9 nmol/mg protein) and proteasome, a major proteolytic enzyme for oxidatively modified proteins were significantly higher in the exercised animals of both age groups (p<.05). The adaptive response against oxidative stress induced by moderate endurance exercise constitutes a beneficial effect of exercise.     

Alpha interferon interaction with opiate receptors in the rat brain

The preferential interactions of alpha-interferon (alpha-IFN) with delta and mu opiate receptors were studied. alpha-IFN (specific antiviral activity 2 X 10(3) U/mg protein) was shown to inhibit in the competitive manner 3H-naloxone and 3H-D-ala2, D-leu5-enkephalin (3H-DADL) specific binding to opiate receptor subpopulations. alpha-IFN was much more effective in decreasing 3H-DADL than 3H-naloxone binding in opiate receptors: K1 values averaged 160 +/- 30 and 1150 +/- 80 U/ml, respectively. IFN effective concentrations inhibiting 50% of 3H-naloxone opiate receptor binding in the absence or presence of 100 mmol/l NaCl were similar, and the "sodium shift" value was equal to 1. The independence of alpha-IFN activity of the presence of NA+ cations suggests the antagonist character of alpha-IFN interaction with opiate receptors. Thus, alpha-IFN employed appears to be an alpha-selective ligand displaying the in vitro properties of "pure" morphine antagonists.     

2,3-Butanedione monoxime does not protect cardiomyocytes under oxidative stress

Heart muscle ischemia-reperfusion provokes a pronounced cardiomyocyte oxidative stress. In the present study, we examined a possible protective effect of the cardioprotective drug, 2,3-butanedione monoxime (BDM), on the cultured neonatal cardiac myocytes exposed to oxidative stress induced by hypochlorous acid (HOCl), that may be formed by activated polymorphonuclear neutrophils in myocardium ischemic-reperfusion areas, and a useful model oxidant, tert-butyl hydroperoxide (tBHP). Using isolated rat cardiomyocytes substantial cytotoxicity of HOCl and tBHP was demonstrated: The concentrations of HOCl and tBHP causing a 50% decrease of cardiomyocyte cell viability were estimated to be 55 +/- 5 microM and 36 +/- 6 microM, respectively. The cell viability measured immediately after the tBHP oxidative treatment was significantly higher than that measured after 22 h of cell post-incubation in a fresh culture medium. This showed delayed cell death after removing tBHP. Hypochlorous acid treatment of cardiomyocytes did not change cellular viability during the cellular post-incubation in a fresh medium. Even a long-term (22 h) incubation of oxidatively damaged cardiomyocytes with BDM (5 mM) added after the HOCl removal did not recover the viability of the HOCl-exposed cells. In the presence of BDM, the cytotoxicity of HOCl significantly increased probably due to a direct reaction of both compounds and toxic chlorinated derivative formation. 2,3-Butanedione monoxime (5 mM) did not reduce cytotoxicity of tBHP, either. Such well-known antioxidative agents as melatonin or glutathione considerably prevented oxidant-induced cell death in a concentration-dependent manner.     

Involvement of gonadotropins in induction of luteolysis in pigs

In our previous study we have demonstrated that treatment of endometrial explants with LH increased 13,14-dihydro-15-ketoprostaglandin F(2alpha) (PGFM) accumulation in pigs. This was particularly visible on Days 14-16 of the estrous cycle. Action of gonadotropin in porcine endometrium appears to be mediated by LH/hCG receptors whose number is dependent on the day of the estrous cycle. In the current study i.v. infusion (1 hour) of hCG (200 IU) performed on Days 10 (n=4) and 12-14 (n=4) of the porcine estrous cycle did not affect plasma PGFM (ng/ml+/-SEM) concentrations. In contrast, administration of hCG on Days 15-17 produced, depending on plasma PGFM level before the infusion period, three different types of response: I. plasma PGFM surge of amplitude 0.62+/-0.15 was observed when the mean basal pre-infusion PGFM plasma level was 0.23+/-0.05 (n=6 gilts); II. the delayed PGFM surge of amplitude 0.62+/-0.15 was determined when basal pre-infusion PGFM level was 0.80+/-0.20 (n=6); and III. lack of PGFM response to hCG was found when basal pre-infusion PGFM level was 1.09+/-0.61 (n=6). Concentrations of plasma PGFM before and after saline infusion did not differ on Days 12-14 and 16 of the estrous cycle. In the next experiment blood samples were collected every 1 hour on Days 12-19 of the estrous cycle to determine concentrations of LH, PGFM and progesterone in four gilts. In particular gilts, plasma peaks of LH closely preceded surges of PGFM in 72.7, 84.6, 75.0 and 66.6 percent, respectively. The highest PGFM surges followed a decline in plasma progesterone concentration. We conclude that the increased PGF(2alpha) metabolite production after hCG infusion during the late luteal phase of the estrous cycle as well as the relationship between plasma LH and PGFM peaks suggest the LH involvement in the elevation of endometrial PGF(2alpha) secretion in pigs, and, in consequence, induction of luteolysis.     

Effects of long-term treatment with GH in the bone mineral density of adults with hypopituitarism and GH deficiency and after discontinuation of GH replacement.

BACKGROUND: Only few previous studies have assessed the effects of long-term growth hormone (GH) replacement therapy on bone mineral density (BMD) in adult patients with GH deficiency. The aim of this study was to investigate the effects of long-term GH therapy on bone metabolism and BMD. MATERIAL AND METHODS: At the start of the study, 20 adults with GH deficiency were randomized to receive either GH, 0.25 IU x kg per week, or placebo. After 6 months, patients in the placebo group were switched to GH therapy, and they received GH for a further 18 months. Of the 20 patients, 14 were male and 6 female with GH deficiency of adult-onset. The mean age of the patients at the start of the study was 40.3+/-10.9 years and the duration of GH deficiency was 10.6+/-6.4 years. Patients deficient in pituitary hormones other than GH had been receiving stable replacement doses of appropriate hormones for at least 6 months before the start of the study. Rates of bone metabolism were assessed by measuring calcium, phosphate, alkaline phosphatase, calciuria, phosphaturia and osteocalcin. BMD was measured by dual X-ray absorptiometry. Body composition was calculated from measurements of bioelectrical impedance. RESULTS: Before GH treatment, BMD in the femoral neck was lower in patients than in controls. The rate of bone resorption markers increased significantly after 6 months and remained stable during the whole treatment period. BMD significantly increased in L2-L4 after 12 months of treatment with an increase of Z-score. The total BMD increase was 4.5+/-6.5%. BMD in the femoral neck increased after 12 months with an increase of Z-score after 18 months. The total increase was 10.4+/-18%. The total BMD increase was not different among patients with or without basal osteopenia. In both groups BMD in L2-L4 and in the femoral neck remained stable after 12 months without GH treatment. Sex, age, BMI and the time in which GH deficiency started, before or after the end of the peak of BMD, did not correlate with BMD. The BMD values and their response to GH treatment did not correlate with other associated deficiencies, and we did not find differences among BMD increase and GH dose, levels of insulin-growth factor-I, insulin growth factor binding protein-3, and parameters of body composition. CONCLUSIONS: The results of the study support previous ones that BMD is subnormal in adults with GH deficiency; that GH replacement therapy stimulates bone turnover with initial biochemical changes; and that in the long term, this stimulation results in a significant augmentation in BMD that continues to increase after 2 years and remains stable after 12 months of GH withdrawal.     

Circulating mononuclear superoxide production and inflammatory markers for long-term prognosis in patients with cardiac syndrome X

Increased oxidative stress and vascular inflammation have been shown in patients with cardiac syndrome X (CSX; angina, exercise-induced ischemia, and normal coronary angiogram). This study was conducted to assess the impact of basal superoxide generation by circulating mononuclear cells (MNCs), a contributor to intravascular oxidative stress, and serum inflammatory biomarkers, including high-sensitivity C-reactive protein, homocysteine, soluble intercellular adhesion molecule-1, soluble vascular adhesion molecule-1, and von Willebrand factor, on the long-term prognosis of CSX. During a mean follow-up of 31.5 +/- 14.2 months (maximum 5 years), a total of 12 events were recorded in 92 consecutive CSX patients. There were no deaths or myocardial infarctions, but 8 hospitalizations for acute coronary syndrome, 3 for stroke, and 1 for congestive heart failure due to left ventricular systolic dysfunction. Under univariate analysis, only basal superoxide generation by MNCs was associated with the risk for cardiovascular event. Based on multivariate analysis, basal superoxide generation by MNCs could still independently predict future events (relative risk for the highest compared to the lowest tertile, 3.87; 95% confidence interval, 1.42-10.54, p = 0.008). These findings demonstrate that long-term prognosis is fair in patients with CSX. Basal superoxide production of MNCs independently predicts future cardiovascular events, suggesting its potential role in measuring disease progression and risk stratification in these patients.     

Plasma testosterone in prepubertal cryptorchid boys under long-term HCG therapy.

Plasma testosterone concentrations were determined before and after 6 weeks of human chorionic gonadotropin treatment in 36 prepubertal boys with bilateral or unilateral cryptorchidism. Mean +/- SD basal and post-treatment values (ng/100 ml) in the bilateral group were: treatment successful (n = 14): 32 +/- 19 and 302 +/- 49, treatment unsuccessful (n = 12): 20 +/- 15 and 176 +/- 73. The figures for the unilateral group were: treatment successful (n = 6): 23 +/- 9 and 244 +/- 41, treatment unsuccessful (n = 5): 22 +/- 11 and 264 +/- 102. In the bilateral group significant differences in the T response emerged when successfully treated boys were compared to unsuccessfully treated ones. It is concluded that Leydig cell function may be impaired in some cases of cryptorchidism.