Thyroid hormone autoantibodies: are they a better marker to detect early thyroid damage in patients with hematologic cancers receiving tyrosine kinase inhibitor or immunoregulatory drug treatments?

BACKGROUND

Unlike cytotoxic agents, novel antineoplastic drugs can variably affect thyroid function and so impair patient outcomes. However, the widely used standard thyroid tests have demonstrated low sensitivity for detecting early thyroid damage that leads to dysfunction of the gland. To find a more reliable thyroid marker, we assessed the presence of antibodies binding thyroid hormones (thAbs) in a cancer population undergoing potentially thyrotoxic treatment.

METHODS

From April 2010 to September 2013, 82 patients with hematologic malignancies treated with tyrosine kinase inhibitors or immunoregulatory drugs were recruited. Healthy volunteers (n = 104) served as control subjects. Thyroid function, autoimmunity tests, thAbs, and thyroid sonography were assessed once during treatment.

RESULTS

Overall, thAb positivity was recorded in 13% of the entire cohort. In most cases, the thAbs were of a single type, with a predominance of T3 immunoglobulin G. More specifically, thAbs were detected in 11 cancer patients; and abnormal levels of thyroid-stimulating hormone, thyroglobulin antibody, and thyroperoxidase antibody were detected in 6 (p = 0.05), 0 (p = 0.0006), and 2 cancer patients (p = 0.001) respectively. Ultrasonographic alterations of the thyroid were observed in 12 cancer patients. In contrast, of the 104 healthy control subjects, only 1 was positive for thAbs (1%).

CONCLUSIONS

We have demonstrated for the first time that thAbs are a reliable marker of early thyroid dysfunction when compared with the widely used standard thyroid tests. A confirmatory prospective trial aiming at evaluating thAbs at various time points during treatment could clarify the incidence and timing of antibody appearance.

Osteoprotegerin and Bone Mineral Density in Hemodiafiltration Patients

A newly identified cytokine, osteoprotegerin (OPG) appears to be involved in the regulation of bone remodeling. In vitro studies suggest that OPG, a soluble member of the TNF receptor family of proteins, inhibits osteoclastogenesis by interrupting the intercellular signaling between osteoblastic stromal cells and osteoclast progenitors. As patients with chronic renal failure (CRF) often have renal osteodystrophy (ROD), we investigated the role of osteoprotegerin (OPG) in ROD, and investigated whether there was any relationship between serum OPG, intact parathyroid (PTH) (iPTH), vitamin D, and trabecular bone. Serum OPG combined with iPTH might be a useful tool in the noninvasive diagnosis of ROD, at least in cases in which the range of PTH values compromises reliable diagnosis. Thirty-six patients on maintenance hemodiafiltration (HDF) and a control group of 36 age and sex matched healthy subjects with no known metabolic bone disease were studied. The following assays were made on serum: iPTH, osteocalcin (BGP), bone alkaline phosphatase, 25(OH)-cholecalciferol, calcium, phosphate, OPG, IGF-1, estradiol, and free testosterone. Serum Ca++, P, B-ALP, BGP, IGF-1, iPTH, and OPG levels were significantly higher in HDF patients than in controls, while DXA measurements and quantitative ultrasound (QUS) parameters were significantly lower. On grouping patients according to their mean OPG levels, we observed significantly lower serum IGF-1, vitamin D3 concentrations, and lumbar spine and hip bone mineral density in the high OPG groups. No correlation was found between OPG and bone turnover markers, whereas a negative correlation was found between serum OPG and IGF-1 levels (r=-0.64, p=0.032). Serum iPTH concentrations were positively correlated with bone alkaline phosphatase (B-ALP) (r=0.69, p=0.038) and BGP (r=0.92, p<0.001). The findings made suggest that an increase in OPG levels may be a compensatory response to elevated bone loss. The low bone mineral density (BMD) levels found in the high OPG group might have been due to the significant decrease in serum IGF-1 and vitamin D3 observed. In conclusion, the findings made in the present study demonstrate that increased OPG in hemodiafiltration patients is only partly due to decreased renal clearance. As it may partly reflect a compensatory response to increased bone loss, this parameter might be helpful in the identification of patients with a marked reduction in trabecular BMD.

[Therapy with vasopressin receptor antagonists: the aquaretics]

Aquaretic drugs, by definition, can induce an increase in urinary volume and urinary free water associated with a decreased urinary osmolarity with a consequent increase in plasma sodium. This enhanced diuresis is not accompanied by an increased loss of electrolytes, whereas traditional diuretics have the opposite, so-called saluretic effect. Aquaretics belong to a family of vasopressin receptor antagonists, V2 in particular, that regulate tubular water reabsorption. Several studies have confirmed their utility in the treatment of hyponatremic states associated with water retention such as heart failure, cirrhosis related ascites and SIADH. Furthermore, new applications may include the treatment of arterial hypertension, polycystic kidney disease, glaucoma and Meniere's syndrome.

[Intravenous immunoglobulins in the treatment of glomerulopathies]

Intravenous high-dose immunoglobulin (IVIG) therapy is used in several antibody-mediated diseases including Guillain-Barré syndrome, idiopathic thrombocytopenic purpura, and autoimmune neuropathies. In the last decade, numerous studies have evaluated the application of IVIG therapy in autoimmune glomerulopathies such as lupus nephritis, membranous glomerulonephritis, and transplant-related chronic nephropathy. These studies were conducted on small numbers of patients and varied with respect to IVIG doses and duration of therapy cycles. Furthermore, many of the patients included in the studies did not respond to conventional therapies, were affected by complications, and had impaired renal function. IVIG therapy was able to reduce proteinuria and inflammation and improve renal function in some forms of glomerulonephritis, particularly LES-related forms. IVIG therapy was also tested in patients awaiting kidney transplantation and in patients affected by transplant-related chronic nephropathy: in both groups the results were controversial. Seventy-eight cases of IVIG-related nephrotoxicity have been reported in the literature. In most cases the toxic effect was reversible and observed in patients with pre-existing renal failure treated with IVIG formulations containing saccharose. IVIG could have beneficial effects in many glomerulopathies. Nevertheless, further trials are needed to clarify the potential and the limitations of this therapeutic approach.

[A brief "update" on renal effects of caffeine]

Caffeine is one of the most frequently consumed substances worldwide. It is present in some common beverages such as tea and coffee and in a variety of drugs, particularly analgesics. Its main mechanisms of action include inhibition of phosphodiesterase enzyme and adenosine receptors; its effects involve the whole body. In recent years there has been a debate in the scientific literature over the relationship between caffeine and the kidney and its possible toxicity. Several experimental studies have demonstrated that caffeine may exacerbate some pathological conditions such as polycystic disease and proteinuria, while others have underlined its protective effects in specific situations. While awaiting new, in-depth studies that will help to solve the debate, we can conclude that there is currently no evidence contraindicating the consumption of moderate quantities of caffeine by healthy subjects or kidney patients.

From the oxygen to the organ protection: erythropoietin as protagonist in internal medicine

Erythropoietin (EPO), already known as the stimulating hormone for erythropoiesis, has shown different and interesting pleiotropic actions. It does not only affect erythroid cells, but also myeloid cells, lymphocytes and megakaryocytes. This hormone can also enhance phagocytic function of the polymorphonuclear cells and reduce the activation of macrophages, thus modulating the inflammatory process.Moreover, hematopoietic and endothelial cells probably have the same cellular origin, and the discovery of erythropoietin receptors (EPO-R) also on mesangial and myocardial cells, smooth muscle fibrocells and neurons has prompted the study of the non-erythropoietic functions of this hormone.The interaction between EPO and VEGF may be of particular importance in neovascularization and wound healing. Different studies have demonstrated that EPO has an important direct hemodynamic and vasoactive action, which does not depend exclusively on any increase in hematocrit and viscosity. Moreover EPO showed protective effects on myocardial cells against apoptosis induced by ischemia/repefusion injury, but it could negatively affect pulmonary hypertension in patient with chronic cor pulmonale.This review aims to stress the importance of the increasing interest in EPO applications and the necessity of further studies to gain a deeper knowledge of this hormone and its pleiotropic and complex actions.

Effect of interleukin 8 and ICAM-1 on calcium-dependent outflow of K+ in erythrocytes from subjects with essential hypertension

INTRODUCTION

The pathogenic mechanisms underlying the increase in peripheral resistance and the contraction of smooth muscular fibre cells in essential hypertension are not yet clearly understood. However, it is now known that immune system activation plays a role in the pathogenesis of some forms of arterial hypertension, and recent data show that the Ca2+ influx in some cells (i.e. red blood cells, leukocytes, platelets, smooth muscular fibre cells) is increased in subjects with essential hypertension, thus revealing a possible alteration in cellular membrane. The end-points of this study were therefore to ascertain whether red blood cells used as a cellular membrane model have a greater Ca2+ dependent K+ flow (Gardos effect) in hypertensive patients than in normotensive controls, to point out a different regulation of ionic channels, and whether IL-8 and the adhesion molecule ICAM-1 influence the membranous outflow.

MATERIAL AND METHODS

The study was conducted on 87 Caucasian subjects. Of these, 50 (25 men, 25 women; mean age 43 +/- 3 years, mean body mass index (BMI) 27 +/- 0.5 and 22.3 +/- 0.3 kg/m(2), respectively) had mild-to-moderate hypertension (mean arterial blood pressure 120 +/- 8 mmHg ). The other 37 (18 men, 19 women; mean age 39 +/- 3 years; BMI 23.8 +/- 0.5 kg/m(2) and 22.8 +/- 0.5 kg/m(2), respectively were normotensive healthy volunteers (mean arterial blood pressure 89 +/- 2 mmHg). All the patients and subjects were untreated for at least 4 weeks before blood sampling.

RESULTS

Ca2+-dependent K+ outflow was found to be greater in samples from patients with essential hypertension than in those from normotensive controls. lL-8 and ICAM-1 significantly enhanced the Ca2+-dependent K+ outflow in red blood cells from hypertensive subjects but had an inhibitory effect on cells from controls. In the experimental model, the presence of TMB-8, a membrane calcium antagonist, significantly reduced the Ca2+-dependent K+ efflux.

CONCLUSION

Vasoconstriction in subjects with essential hypertension may therefore depend on a different regulation of ionic flow that probably supports an increased Ca2+ inflow in smooth muscle fibre cells. Under certain pathological conditions, some immune system components (i.e. interleukins, adhesion molecules) may directly enhance membrane permeability to Ca2+, thus inducing vasoconstriction in the smooth muscle cells.

The pleiotropic effects of erythropoietin in the central nervous system

Erythropoietin (Epo) is a hydrophobic sialoglycoproteic hormone produced by the kidney and responsible for the proliferation, maturation, and differentiation of the precursors of the erythroid cell line. Human recombinant erythropoietin (rHuEpo) is used to treat different types of anemia, not only in uremic patients but also in newborns with anemia of prematurity, in patients with cancer-related anemia or myeloproliferative disease, thalassemias, bone marrow transplants, or those with chronic infectious diseases. The pleiotropic functions of Epo are well known. It has been shown that this hormone can modulate the inflammatory and immune response, has direct hemodynamic and vasoactive effects, could be considered a proangiogenic factor because of its interaction with vascular endothelial growth factor, and its ability to stimulate mitosis and motility of endothelial cells. The multifunctional role of Epo has further been confirmed by the discovery in the central nervous system of a specific Epo/Epo receptor (EpoR) system. Both Epo and EpoR are expressed by astrocytes and neurons and Epo is present in the cerebrospinal fluid (CSF). Therefore, novel functions of Epo, tissue-specific regulation, and the mechanisms of action have been investigated. In this review we have tried to summarize the current data on the role of Epo on brain function. We discuss the different sites of cerebral expression and mechanisms of regulation of Epo and its receptor and its role in the development and maturation of the brain. Second, we discuss the neurotrophic and neuroprotective function of Epo in different conditions of neuronal damage, such as hypoxia, cerebral ischemia, and subarachnoid hemorrhage, and the consequent possibility that rHuEpo therapy could soon be used in clinical practice to limit neuronal damage induced by these diseases.

AQP1 in red blood cells of uremic patients during hemodialytic treatment

Hemodialysis influences the transport of water through the erythrocytic membrane, and induces morphologic and functional modifications. Recently water channels, called aquaporins (AQP), have been identified on the membrane of red blood cells. The aim of the present study was, therefore, to evaluate any relationships between volumetric changes in erythrocytes (MCV), plasma osmolarity and membrane expression of AQP1 in 22 uremic patients during a hemodialysis session, and compare value with those in a control group of 22 healthy volunteers. Membranal AQP1 expression was evaluated using three methods: indirect immunofluorescence under confocal microscopy, immunoenzymatic method after membrane extraction, and immunoblotting. In uremic subjects, at baseline membrane AQP1 expression was significantly lower, whereas plasma osmolality was higher than in controls. At 1 and 2 h of replacement therapy, a progressive increase was observed in erythrocytic AQP1, values similar to those in controls being attained after 3.5 h. During the session osmolality values reduced progressively, becoming significantly lower than basal values. The mean erythrocytic corpuscular volume in patients with ESRD was significantly lower than in cntrols at baseline. This value increased during hemodialysis, attaining statistical significance with respect to the basal value at 3.5 h of dialysis. Close correlations were found between plasma osmolality and AQP1 values (r = -0.930; p < 0.05), and also between MCV and plasma osmolality trend (r = -0.909; p < 0.05). There was a linear correlation (r = 0.63, p < 0.05) between plasma AVP concentrations and plasma osmolality. The variations found in plasma osmolarity during hemodialysis, may induce AQP1 expression on the membrane of intact red blood cells.

Erythropoietin and the brain: from neurodevelopment to neuroprotection

It is now widely known that erythropoietin (Epo) does not only affect the haematopoietic system, but it can be considered a multifunctional trophic factor with an effect on the general homoeostasis of the entire organism. The recent discovery of a specific Epo/Epo-receptor system in the central nervous system (CNS) and cerebrospinal fluid, independently of the haematopoietic system, has further paved the way for new studies aimed at investigating the different sites of cerebral expression of Epo and its receptor, the regulation of their expression and, finally, the effects that this hormone has on the development and maturation of the brain. A further aim has been to investigate how it influences CNS homoeostasis and neurotransmission in adult brain. Attention has also been focused on the neurotrophic and neuroprotective function of Epo in different conditions of neuronal damage, such as hypoxia, cerebral ischaemia and subarachnoid haemorrhage, and therefore on the possibility that human recombinant Epo therapy could soon be used in clinical practice, also to limit neuronal damage induced by these diseases.

[Diverticular disease of the colon in peritoneal dialysis]

Colon diverticular disease is a very common pathology in western countries and represents a risk factor for septic-type complications, especially in peritoneal dialysis patients. We examined both diagnostic procedure and therapeutics options, either pharmacological or surgical. Ultrasonography, which is useful for the diagnosis of diverticulosis and diverticular disease, has been supported in the last few years by new imaging techniques, such as NMR and CT, that also find applications in the treatment of diverticulitis complications like peritoneal abscesses. Our emphasis is on the therapeutic perspective, either dietetic - based on the use of a fibre-rich diet and the infusion of liquids by intravenous injection - or surgical, such as the Hartmann procedure, single anastomosis with stomia conservation and laparoscopic and endoscopic treatment. These therapeutic approaches have reduced both morbidity and mortality rate and have emphasized how the reduction of surgical stress on the mesothelium promotes the recovery of the functional integrity and, consequently, faster resumption of peritoneal dialysis. In conclusion, diverticulosis alone is not a contraindication for peritoneal dialysis, but constitutes a risk factor for the continuation of this alternative treatment.

Effects of homocysteine on proliferation, necrosis, and apoptosis of vascular smooth muscle cells in culture and influence of folic acid

BACKGROUND

It is known that hyperhomocysteinemia is associated with an increased risk of vascular disease, yet little is known about the pathogenic mechanisms underlying the action of homocysteine (Hcy) itself.

METHODS

We evaluated the effects of Hcy on cell proliferation, apoptosis, and necrosis in smooth muscle cells (SMCs) cultured for 24 h with different amounts of Hcy. The percentage of apoptotic and necrotic cells from the culture was evaluated using two different techniques: annexin V-FITC and propidium iodide (PI) fluorescence and apoptosis TUNEL assay.

RESULTS

The addition of 10 microM/l of Hcy to the medium was followed by a significant increase in cell proliferation and death, through apoptosis and necrosis, respectively. Notwithstanding this apparent balance, a significant increase was found in the total number of cells present in Hcy-treated culture, thus demonstrating a positive dose-dependent correlation with Hcy concentrations in the culture medium. The addition of folic acid to the culture medium significantly reduced both Hcy concentrations in media and the effects of Hcy on the proliferation/apoptosis/necrosis balance of cells in culture. The percentages for apoptotic cells and for cells with a necrotic morphology continued to increase as Hcy concentrations increased, although the absolute values were lower in the culture treated than in that not treated with folic acid.

CONCLUSIONS

In the presence of folic acid, at increasing concentrations of Hcy, the total number of cells in culture showed increases far less relevant with respect to the control. Also the percentage of apoptotic cells to that of cells with a necrotic morphology, although conserving the tendency to increase to growth of the concentrations of Hcy, have shown absolute values that were lower in the folic acid-treated cultures.

Urinary excretion of aquaporin-2 water channel during pregnancy

BACKGROUND

In healthy primiparas the total body water content increases by about 8 liters within the last trimester, with a consequent reduction in plasma arginine-vasopressin (AVP) levels. The aim of the present study was to investigate the effect of normal pregnancy on urinary excretion of AQP2, a vasopressin sensitive water channel.

METHODS

Forty-five healthy pregnant primiparas (specify mean age and range) with a physiological single-fetus pregnancy were studied during weeks 12, 24 and 36 of pregnancy and then for 3 to 5 days postpartum. The control group consisted of 14 age-matched women in the early follicular phase of the menstrual cycle (day 5 or 6). The behavior of plasma AVP, ANP, oxytocin, urinary 6-keto-PGF1alpha (a metabolite of prostacyclin) and urinary AQP-2 excretion were evaluated in all subjects.

RESULTS

Plasma ANP and oxytocin, and urinary AQP-2 and 6kPGF1alpha excretion increased during all three trimesters, with the highest peaks at the 36(th) week. In the postpartum period, these values markedly decreased. No statistically significant changes were found in plasma AVP levels throughout the study period.

CONCLUSIONS

Our findings suggest that a non-AVP factor present in pregnancy plays a role in the control of the excretion of AQP-2 water channels.

Cell proliferation/cell death balance in renal cell cultures after exposure to a static magnetic field

The effect of a static magnetic field (MF) of 0.5 mT of intensity on the cell proliferation/cell death balance was investigated in renal cells (VERO) and cortical astrocyte cultures from rats. Magnetic stimulation was delivered by magnetic disks at known intensities. The percentage of apoptotic and necrotic cells was evaluated using flow cytometry and morphological analysis following Hoechst chromatin staining. An index of cell proliferation was determined using sulfonated tetrazolium (WST-1). Control cultures were prepared without exposure to MFs. After 2, 4 and 6 days of exposure to a MF, we observed a gradual decrease in apoptosis and proliferation and a gradual increase in cells with a necrotic morphology with respect to the control group. In astrocyte cultures, over a 6-day exposure period. A gradual increase was observed in apoptotic, proliferating, and necrotic cells. Our findings suggest that the effect of exposure to MFs varies, depending on the cell type; MFs may also have a nephropathogenic effect.

Water immersion increases urinary excretion of aquaporin-2 in healthy humans

Many previous studies have shown that aquaporin-2 (AQP2), the vasopressin-regulated water channel, is excreted in the urine and that the excretion increases in response to vasopressin. Moreover, recently a close correlation between AQP2 excretion in urine and kidney AQP2 expression has been demonstrated, showing that urinary excretion of AQP2 is a reliable indicator for AQP-2 function. As head-out water immersion causes an expansion in the central vascular volume equal to that induced by 2 liters of saline, without modifying plasma composition, we used immersion in water to evaluate if the response to acute expansion of the central vascular volume could involve vasporessin (AVP) and AQP2. In healthy subjects, concentrations of plasma atrial natriuretic factor (ANF) and AVP, and urinary AQP2 were measured during a 2-hour immersion period. In all subjects, immersion caused a prompt and marked increase in immunoreactive ANF (23.0 +/- 2.12 pg/ml at second hour vs. 2.17 +/- 0.42 pg/ml at baseline) and in urinary excretion of AQP2 (23.9 +/- 2. 69 pmol/mg creatinine at second hour vs. 4.42 +/- 0.14 pmol/mg creatinine at baseline), while a significant decrease was found in plasma AVP. Recovery was associated with a prompt return to pre-study levels. These findings demonstrate that heat-out water immersion stimulates urinary excretion of AQP2 in absence of an increase in plasma AVP.

Cardiovascular remodeling, apoptosis, and drugs

Apoptosis, a form of programmed cell death, mediates the controlled deletion of so-called "unwanted" cells. This review deals with the key features of this cell death program, showing that apoptosis is regulated by factors extrinsic and intrinsic to the dying cell. The elucidation of the possible interactions between these factors may be of major interest in preventing the progression to cardiovascular remodeling in patients with hypertensive disease. New pathways of research are emerging for drugs, such as beta-blockers, ACE inhibitors, the calcium-antagonists, and the receptor antagonist of angiotensin II, all of which have beneficial effects on cardiovascular remodeling. This may be due to the direct effect of these drugs on the cell proliferation/apoptosis balance.

Effect of fluvastatin on proteinuria in patients with immunoglobulin A nephropathy

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are established drugs for the treatment of hypercholesterolemia, but several studies have shown that benefits obtained with these drugs are not causally related only to regression of cholesterol lowering. Moreover, in experimental models of progressive renal disease, statins have reduced the extent of glomerulosclerosis. This study evaluated the antiproteinuric effect of a daily dose of 40 mg fluvastatin for 6 months in moderately proteinuric patients with immunoglobulin A nephropathy, stable renal function, and no indicators of poor long-term prognosis. The effects of therapy were evaluated on the basis of 24-hour proteinuria (total proteinuria and albuminuria), albuminemia, creatinine clearance, cholesterol, and triglyceride values. Renal function remained stable in all patients. A significant decrease in proteinuria was observed after 6 months of therapy and persisted for all the observations. An increase in serum albumin was observed after 6 months of therapy. This study suggests that there is an antiproteinuric effect of HMG-CoA reductase inhibitors in moderately proteinuric patients with immunoglobulin A nephropathy.

In vivo evidence that erythropoietin has a neuroprotective effect during subarachnoid hemorrhage

To ascertain in vivo whether recombinant human erythropoietin has a neuroprotective effect on the cortex during subarachnoid hemorrhage, 56 rabbits were divided into the following groups: Group 1 control sham operated plus placebo (n=14; saline solution - NaCl 0.9%); Group 2 control sham operated plus recombinant human erythropoietin (n=14); Group 3 subarachnoid hemorrhage plus placebo (n=14); Group 4 subarachnoid hemorrhage plus recombinant human erythropoietin (n=14; intraperitoneal administration of recombinant human erythropoietin immediately after inducing subarachnoid hemorrhage). In none of the Groups 1 and 2 animals was subarachnoid hemorrhage induced. In Group 3 rabbits, an increase in locomotor activity (open field apparatus) was observed 24, 48 and 72 h after surgery, and the mortality rate was 42.9% within 72 h after surgery, and, no increase in locomotor activity was observed in Group 4 rabbits, which survived for at least 72 h. Our findings suggest that recombinant human erythropoietin may be of benefit in the treatment of subarachnoid hemorrhage.

Effects of lisinopril administration on blood bcl-2 concentrations in patients with immunoglobulin A nephropathy

We evaluated blood concentrations of bcl-2, a proto-oncogene that can inhibit apoptotic phenomena, in a group of patients with immunoglobulin A (IgA) nephropathy. Concentrations of bcl-2 were higher in patients with proteinuria than in those without proteinuria. A 6-month course of 5 mg/day lisinopril given to subjects with proteinuria significantly reduced blood bcl-2 concentrations and caused a reduction in proteinuria. Therefore increased blood bcl-2 concentrations may be considered an index of risk in subjects with IgA nephropathy, and the positive effects of angiotensin-converting enzyme inhibitors on proteinuria in patients with IgA nephropathy may be attributed, at least in part, to their effect on the mechanisms that regulate apoptosis. This is of fundamental importance in resolving glomerular hypercellularity in the course of glomerulonephritis.

Reduced blood bcl-2 protein concentration in patients on hemodialysis

The concentrations of bcl-2 protein that can block programmed cellular death in various cell lines were evaluated in blood samples from 10 uremic patients on hemodialysis, 10 uremics not yet on hemodialysis, and in 10 healthy controls. The bcl-2 protein variations (in uremics on dialysis) were ascertained in patients during the dialysis session. Oxidative stress was evaluated in all groups by assaying the products of intraerythrocytic lipoperoxidation. Dialyzed and nondialyzed uremic patients had higher bcl-2 protein concentrations than healthy subjects. Dialysis causes a significant reduction in the concentrations of bcl-2 protein which becomes statistically significant during the 3rd hour. In both groups of uremic patients a positive correlation was found between bcl-2 protein and products of lipoperoxidation.

Pro-apoptotic effect of fluvastatin on human smooth muscle cells

The antiatherosclerotic effect of statins has been attributed to their hypocholesterolemic action. We therefore evaluated the effect, in vitro, of the addition of the serum of patients taking fluvastatin on human smooth muscle cells in order to ascertain the effect of the drug on cell proliferation and apoptosis. We found that the addition of serum from patients treated with fluvastatin for 6 days caused a significant reduction in cell proliferation, increased cell apoptosis and reduced the B cell leukemia-2 (bcl-2) concentration. It is concluded that the induction of apoptosis by statins could be a supplementary mechanism in the prevention of atherosclerotic lesions in humans.

Reduced bcl-2 concentrations in hypertensive patients after lisinopril or nifedipine administration

In 30 patients with essential hypertension and 30 healthy control subjects, we evaluated blood concentrations of B cell leukemia-2 (bcl-2), a protooncogene that can reduce apoptosis. Bcl-2 concentrations were higher in hypertensive than in normotensive subjects. The increase in pressure due to a cold pressor test caused a further increase in blood bcl-2 concentrations, in both hypertensive and normotensive subjects. Treatment of hypertensive patients with hypotensive drugs caused a reduction in bcl-2 concentrations, which was more marked after administration of lisinopril than of nifedipine. The results suggest that concentrations of bcl-2 are increased in patients with hypertension, which could be an important factor in cell proliferation underlying posthypertensive vascular remodeling. Moreover, lisinopril and nifedipine appear to be capable of reducing bcl-2 concentrations, with potentially beneficial effects on vascular modifications in patients with hypertension.

Is apoptosis cause of pre-eclampsia?

Pre-eclampsia is the main cause of fetal and maternal morbidity and death associated with hypertension during complicating pregnancy. During physiological pregnancy, the immunological system undergoes secondary modifications, with an "exchange" between mother and fetus. Cytokines play an important role in the complex condition of partial fetal "rejection". It has suggested that the condition depend on immunological factors. In line with this hypothesis, apoptosis appear to play a key role in the pathophysiology of placental ischemia and the mechanism underlying this condition may be influenced by substances such as Bcl-2 which inhibits apoptosis. Neither aspirin nor calcium appear to improve maternal hypertension and proteinuria, although late ongoing trials may alter this view. At present, the condition can be resolved only by the end of pregnancy. Further studies are required in order to improve our understanding of these immunological mechanisms underlying hypertension during pregnancy, as the key to effective therapy may be their ability to "manipulate" them in an appropriate way.

Rapid and transient lymphocytopenia after i.v. administration of high doses of human recombinant erythropoietin

The effect of administration of human recombinant erythropoietin on leukocytic cells has been evaluated. In humans the administration of 20,000 U i.v. of rHuEPO caused a rapid and transitory leukopenia that seemed to be caused by a preferential reduction of lymphocytes (2715 +/- 513 mm3 t 0; 1898 +/- 506 t 60', p < 0.002). Pretreatment with imidazole-2-hydroxybenzoate, a drug capable of inhibiting the synthesis of prostaglandins, caused a less marked and later reduction of lymphocytes (2242 +/- 477 t 0; 1560 +/- 318 t 180 minutes, p < 0.001). A less marked and later lymphocytopenia was also shown in subjects affected by chronic renal insufficiency (2907 +/- 726 t 0; 1944 +/- 512 t 180 minutes, p < 0.005).

Cold pressor test raises serum concentrations of ICAM-1, VCAM-1, and E-selectin in normotensive and hypertensive patients

In patients with essential hypertension, elevated soluble E-selectin (sE-selectin) levels may indicate endothelial cell injury or activation. We therefore sought to ascertain whether arterial blood pressure increased by the cold pressor test can modify serum concentrations of sE-selectin and other soluble forms of adhesion molecules, such as soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1), or the expression of any adhesion molecules in circulating monocytes and lymphocytes. Our findings show that levels of sE-selectin, sVCAM-1, and sICAM-1 are higher in patients with essential hypertension than in normotensive subjects (sICAM-1, 380 +/- 52 versus 262 +/- 96 ng/mL, P<.05; sVCAM-1, 720 +/- 52 versus 625 +/- 38 ng/mL, P<.05; and sE-selectin, 75 +/- 21 versus 61 +/- 22 ng/mL, P<.05). Furthermore, in normotensive and hypertensive patients, the cold pressor test caused an increase in serum concentrations of sICAM-1, sVCAM-1, and sE-selectin, but it did not cause changes in the expression of adhesion molecules in circulating monocytes and lymphocytes. High arterial blood pressure may therefore increase the production of serum adhesion molecules, probably through endothelial activation.

Renal failure from mitochondrial cytopathies

Mitochondrial cytopathies are metabolic diseases, expressing mutations in nuclear DNA, punctiform mutations or depletions in mitochondrial DNA. These genetic lesions alter mitochondrial oxidative phosphorylation, with a reduction in energy produced for cell activity. Renal disease may be the first sign of mitochondrial cytopathy, or it may appear together with neurological and neuromuscular signs. Fanconi's syndrome, a benign sign of renal tubulopathy, is particularly frequent in newborns with mitochondrial cytopathy, whereas tubulointerstitial nephropathy, which affects infants and adults, is more serious because it develops into terminal uremia. Findings of hyperlactatemia and reduced enzymatic activity on the respiratory chain in tissue biopsies are of diagnostic significance in mitochondrial cytopathy. A breakthrough is being made in our understanding of genetic alterations in mitochondrial DNA, and with future therapy, the kidney, a target organ, may be safeguarded.

[Rapid, progressive deterioration of renal function following erroneous administration of high doses of subcutaneous recombinant erythropoietin]

It's reported a case of progressive and rapid deterioration of the renal function, following to a wrong administration of high doses of recombinant erythropoietin. After the administration of 10,000 U of rHuEPO three times a week for at least five times instead of the 1000 U ordered, the patient showed a progressive increase of the plasmatic creatinine values from 2.2 to 3.3 mg/dl. In the same period we pointed out an increase of hematocrit (from 29% to 35%) and of the Hb (from 9.3 to 11.2 g/dl). The patient, suffering from a slightly high blood pressure, furthermore showed important pressure increases. The suspension of the treatment by erythropoietin permitted the restoration of the creatinine values to levels similar to the ones pointed out before the treatment and a reduction of the blood pressure values. The AA. think that a too rapid regression of the anaemia achieved by a rHuEPO treatment can condition a worsening of the renal function in the pre uraemic patient.