Circulating cell-free DNA levels in Portuguese patients with psoriasis vulgaris according to severity and therapy.

BACKGROUND: Inflammation has a key role in the pathogenesis of psoriasis. Circulating cell-free DNA (CFD) is a marker of tissue cell damage closely associated with inflammation. OBJECTIVES: We aimed to understand the relation of CFD levels with psoriasis severity, defined by the Psoriasis Area and Severity Index (PASI), with inflammation and with psoriasis therapy. METHODS: Forty-six patients with psoriasis vulgaris were evaluated before (T0) and after 12 weeks (T12) of treatment with narrowband ultraviolet light B (NB-UVB; n = 17), psoralen plus UVA (PUVA; n = 20) or topical therapy (n = 9). We evaluated interleukin (IL)-6 and circulating CFD levels. RESULTS: Compared with controls, at T0, patients presented significantly higher levels of circulating CFD. CFD presented a significant positive correlation with IL-6 and a trend towards a positive correlation with PASI. Multiple linear regression analysis identified IL-6 as an independent variable associated with CFD circulating levels. As shown by the PASI score, a trend towards higher values of CFD was observed in the severe psoriasis forms; moderate and severe psoriasis presented also significantly higher CFD values, compared with control. Both NB-UVB and PUVA treatments significantly decreased the levels of CFD. CONCLUSIONS: Patients with psoriasis, at the active stage of the disease, presented an increased inflammation associated with raised circulating CFD levels, which seem to be linked to psoriasis severity. Both NB-UVB and PUVA, anti-inflammatory therapies, were effective in decreasing CFD values. We propose that the evaluation of circulating CFD may provide a new biomarker to monitor psoriasis, its severity and its treatment.

Cytotoxic and genotoxic effects of acitretin, alone or in combination with psoralen-ultraviolet A or narrow-band ultraviolet B-therapy in psoriatic patients.

Acitretin is currently used alone or combined with PUVA (psoralen + UVA) or with narrow-band ultraviolet B (NBUVB), to treat moderate and severe psoriasis. However, little is known about the potential genotoxic/carcinogenic risk and the cytostatic/cytotoxic effects of these treatments. Our aim was to study the cytotoxic and genotoxic effects of acitretin - alone or in combination with PUVA or NBUVB - by performing studies with blood from patients with psoriasis vulgaris who were treated with acitretin, acitretin+PUVA or acitretin+NBUVB for 12 weeks, and in vitro studies with blood from healthy volunteers, which was incubated with acitretin at different concentrations. The cytotoxic and genotoxic effects were evaluated by the cytokinesis-blocked micronucleus test and the comet assay. Our results show that psoriatic patients treated with acitretin alone or with acitretin+NBUVB, did not show genotoxic effects. In addition, these therapies reduced the rate of proliferation and induced apoptosis and necrosis of lymphocytes; the same occurred with lymphocyte cultures incubated with acitretin (1.2-20µM). The acitretin+PUVA reduced also the proliferation rate, and increased the necrotic lymphocytes. Our studies suggest that therapy with acitretin alone or combined with NBUVB, as used in psoriatic patients, does not show genotoxic effects, reduces the rate of proliferation and induces apoptosis and necrosis of lymphocytes. The combination of acitretin with PUVA also reduces the proliferation rate and increases the number of necrotic lymphocytes. However, as it induced slight genotoxic effects, further studies are needed to clarify its genotoxic potential.

Interleukin (IL)-22, IL-17, IL-23, IL-8, vascular endothelial growth factor and tumour necrosis factor-α levels in patients with psoriasis before, during and after psoralen-ultraviolet A and narrowband ultraviolet B therapy.

BACKGROUND: Several cross-sectional studies have shown that different cytokines and growth factors are enhanced in psoriasis. OBJECTIVES: We aimed to understand the role/relation of interleukin (IL)-22, IL-17, IL-23, IL-8, vascular endothelial growth factor (VEGF) and tumour necrosis factor (TNF)-α in psoriasis vulgaris, addressing their levels and changes before, during and after psoralen-ultraviolet A (PUVA) and narrowband ultraviolet B (NB-UVB) treatment. METHODS: A cross-sectional and a longitudinal study (n = 34) - before (T0) and at 3 (T3), 6 (T6) and 12 (T12) weeks of NB-UVB and PUVA therapy - were performed; 17 patients started NB-UVB and 17 PUVA, and IL-22, IL-17, IL-23, IL-8, TNF-α and VEGF levels were evaluated. RESULTS: At T0, compared with controls (n = 20), all the parameters were significantly higher in patients, except for TNF-α. Both NB-UVB and PUVA treatment gave, at T3, a significant decrease in TNF-α and IL-23; IL-22 and IL-17 decreased significantly at T6; all parameters and Psoriasis Area and Severity Index decreased significantly at T12. However, in both groups, at T12, VEGF was still significantly higher than control. CONCLUSIONS: Psoriasis seems to be a complex disease in which the cytokine network is disturbed, namely in levels of IL-22, IL-17, IL-23, IL-8, TNF-α and VEGF. NB-UVB and PUVA follow-up studies suggested that the reduction in the IL-23/Th17 axis might be important in the pathogenic mechanisms of psoriasis. Further follow-up studies of patients with psoriasis treated with these and other therapies could be very helpful for the understanding of the disturbance in the cytokine network in psoriasis and indirectly in its pathogenesis.

Circulating adipokine levels in Portuguese patients with psoriasis vulgaris according to body mass index, severity and therapy.

BACKGROUND: Psoriasis vulgaris is associated with overweight/obesity and with increased C-reactive protein (CRP), tumour necrosis factor (TNF)-α, interleukin (IL)-6, leptin and resistin levels and decreased adiponectin levels. OBJECTIVES: To understand the role/relationship of adipokines, as well as CRP, in a Portuguese psoriatic population, by assessing the relationship of their levels with psoriasis severity, defined by Psoriasis Area and Severity Index (PASI), with obesity, defined by body mass index (BMI), and psoriasis therapy. METHODS: A cross-sectional (n=66) and longitudinal study (before and after 12 weeks of therapy; n=44) was performed; 10 patients started topical treatment, 17 narrow-band ultraviolet B (NBUVB) and 17 psolaren associated with UVA (PUVA). RESULTS: Patients presented significantly higher BMI, leptin, resistin, TNF-α, IL-6 and CRP and significantly lower adiponectin values. CRP and IL-6 correlated with PASI. Adiponectin and leptin were more altered in patients with higher BMI. Concerning severity, CRP, resistin and adiponectin were more altered in the severer forms. After treatment, a significant reduction in PASI, CRP, resistin, TNF-α and IL-6, and a significant rise in adiponectin were observed. Nonetheless, CRP and adiponectin remained different from those of control. Concerning therapies, topical therapy was not associated with any significant change, except for TNF-α. After NBUVB, a significant reduction was observed in TNF-α and in CRP. For PUVA, we observed a significant reduction in TNF-α, IL-6 and CRP, and a significant increase in adiponectin. CONCLUSION: In psoriatic patients, increased overweight/obesity was associated with raised leptin levels and decreased adiponectin levels. Leptin may contribute to enhance the inflammatory process in overweight/obese psoriatic patients. Resistin, IL-6, CRP and adiponectin levels appear to be dependent on psoriasis severity. CRP, together with IL-6, appears to be a useful marker of psoriasis severity. Both NBUVB and PUVA were effective; however, PUVA results seem to be more successful. Nonetheless, after NBUVB and PUVA, a low-grade inflammation still persists.

C-reactive protein and leucocyte activation in psoriasis vulgaris according to severity and therapy.

BACKGROUND: Psoriasis vulgaris is a chronic recurrent inflammatory skin disease and psoriatic lesions have shown leucocyte infiltration. OBJECTIVES: We aimed to study C-reactive protein (CRP) and leucocyte activation markers/inhibitors as potential monitors of psoriasis vulgaris. METHODS: A cross-sectional (n = 73) and a longitudinal study (before, at 3, 6 and 12 weeks of therapy; n = 47) was performed; 10 patients started topical treatment, 17 narrow-band ultraviolet light B (NBUVB) and 20 psolaren associated to UVA (PUVA); psoriasis severity was defined by Psoriasis Area and Severity Index (PASI). RESULTS: Compared with control (n = 38), we found higher CRP levels, total leukocyte/neutrophil count, elastase, lactoferrin and alpha1-antitrypsin. Increasing PASI was linked to increasing CRP and a trend to higher elastase and lactoferrin, suggesting that worsening enhances inflammatory response with neutrophil activation. CRP correlated with PASI, total leucocytes, neutrophils, elastase, lactoferrin and alpha1-antitrypsin. NBUVB and PUVA presented similar effects. CONCLUSION: We propose CRP as a useful marker of psoriasis severity that could be used to monitor psoriasis and its treatment, and, together with PASI and elastase, could also be used as a global index of severity.

Exercise training decreases proinflammatory profile in Zucker diabetic (type 2) fatty rats.

OBJECTIVE: In the present study we evaluated the effect of exercise on the plasma levels of proinflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), and the anti-inflammatory molecule uric acid in the Zucker diabetic fatty (ZDF) rats that are more prone to develop type 2 diabetes mellitus. METHODS: Sixteen obese ZDF (Gmi fa/fa) rats (8 wk old, 228.40 +/- 4.05 g) were randomly assigned to one of two groups (n = 8 each): an exercise-trained group and a sedentary one. In addition, 16 lean ZDF (Gmi +/+) rats (8 wk old, 199.00 +/- 3.50 g) were subjected to identical sedentary and exercise conditioning (n = 8 each). Initially, rats swam 15 min/d (5 d/wk) in a 36 degrees C bath. The exercise protocol was gradually increased by 15 min/d until a swimming period of 1 h/d (1 wk) was attained. Thereafter, rats swam 1 h/d, 3 d/wk, for an additional period of 11 wk. Rats were sacrificed 48 h after the last training period and the blood and pancreas were collected. Circulating levels of glucose, glycosylated hemoglobin, total cholesterol, triglycerides, insulin, uric acid, IL-6, and TNF-alpha were assessed. The concentrations of proinflammatory cytokines in the pancreas were also evaluated. RESULTS: In the diabetic ZDF (fa/fa) rats, exercise decreased hyperuricemia (-37.3%) and IL-6 and TNF-alpha levels (-16.9% and -12.7% respectively) and maintained the weight of the pancreas at near normal. Immunohistochemistry revealed a marked decrease in the expression of TNF-alpha and IL-6 in the pancreatic islet cells of ZDF (fa/fa) rats. CONCLUSION: These results indicate that aerobic exercise is anti-inflammatory in nature.

Hypertension induced by immunosuppressive drugs: a comparative analysis between sirolimus and cyclosporine.

The purpose of this study was to compare the effects of sirolimus (SRL) vs cyclosporine (CsA) concerning the cardiovascular mechanisms hypothetically contributing to hypertension development. Three rat groups were studied: control (vehicle), CsA (5 mg/kg/d), and SRL (1 mg/kg/d). The following parameters were evaluated after 7 weeks of treatment: blood pressured (BP) and heart rate (HR; tail cuff), lipid profile, hematology, plasma and platelet 5-HT and catecholamines (HPLC-ECD), and oxidative equilibrium (serum malondialdehyde [MDA] and total antioxidant status [TAS]). Systolic (SBP) and diastolic blood pressure (DBP) values were higher (P < .001) in both the CsA (146.2 +/- 4.5 and 124.9 +/- 4.5 mm Hg) and SRL (148.9 +/- 4.8 and 126.4 +/- 6.0 mm Hg) groups vs the controls (115.9 +/- 3.3 and 99.1 +/- 2.0 mm Hg). However, HR values were elevated in CsA but not SRL animals. The dyslipidemic pattern of CsA was even more enhanced in the SRL group, with significantly higher low-density lipoprotein cholesterol (LDL-c) and triglyceride (TG) levels vs CsA (P < .05); red blood cells, hematocrit, hemoglobin concentration, mean platelet volume, and platelet distribution width were significantly (P < .05) higher in the SRL vs CsA group. The pro-oxidative profile (increased MDA/TAS) in the CsA group was not reproduced in the SRL cohort. While plasma and platelet 5-HT were elevated in SRL rats, catecholamine content was higher in CsA animals. In conclusion, this study demonstrated that CsA and SRL produce identical hypertensive effects. However, while CsA promotes oxidative stress and sympathetic activation, SRL mainly interferes with lipid profile and hematological parameters. Thus, the hypertensive effects of CsA, a calcineurin inhibitor, and of SRL, an mTOR inhibitor, are associated with impairment of distinct cardiovascular pathways.

Characterization of a rat model of moderate chronic renal failure--focus on hematological, biochemical, and cardio-renal profiles.

The pathophysiological modifications underlying chronic renal failure seems to be dependent on the insufficiency degree, which will determine the moment to start therapy. As there is yet limited information about animal models of moderate chronic renal failure, we intended to perform a complete characterization of the hematological and cardio-renal alterations induced by partial nephrectomy. Blood samples from control and chronic renal failure rats were collected at 0, 3, 9, and 15 weeks in order to evaluate renal function, hematological parameters, iron metabolism, blood lipids, peripheral sympathetic nervous system, and inflammatory and redox status markers. BP, tissues trophy indexes, and kidney histomorphology were also assessed. Our data are consistent with a sustained moderate degree of chronic renal failure with a quickly compensated modest anaemia, though presenting iron metabolism disturbances. Despite the reasonable degree of functionality of the remnant kidney, as suggested by the anaemia correction and by the kidney hypertrophy and moderate lesions, several important cardiovascular modifications were developed. Our model presented hypertension, dyslipidemia, erythropoietic disturbances, sympathetic activation, and oxidative stress. This model might be a good tool to study the cellular/molecular mechanisms underlying moderate stages of chronic renal failure and to evaluate the therapeutic efficacy for prevention and treatment/correction of cardio-renal anaemia syndromes and complications in early stages.

Cross-talk between inflammation,coagulation/fibrinolysis and vascular access in hemodialysis patients.

This work aimed to study the association between fibrinolytic/endothelial cell function and inflammatory markers in chronic kidney disease (CKD) patients undergoing hemodialysis (HD) and recombinant human erythropoietin (rhEPO) therapies, and its relationship with the type of vascular access (VA) used for the HD procedure. As fibrinolytic/endothelial cell function markers we evaluated plasminogen activator inhibitor type-1 (PAI-1), tissue plasminogen activator (tPA) and D-dimers, and as inflammatory markers; C-reactive protein (CRP), soluble interleukin (IL)-2 receptor (s-IL2R), IL-6 and serum albumin levels. The study was performed in 50 CKD patients undergoing regular HD, 11 with a central venous dialysis catheter (CVC) and 39 with an arteriovenous fistula (AVF), and in 25 healthy controls. Compared to controls, CKD patients presented with significantly higher levels of CRP, s-IL2R, IL-6 and D-dimers, and significantly lower levels of PAI-1. The tPA/PAI-1 ratio was significantly higher in CKD patients. We also found statistical significant correlations in CKD patients between D-dimerslevels and inflammatory markers: CRP, albumin, s-IL2R and IL-6. When comparing the two groups of CKD patients, we found that those with a CVC presented statistically significant lower levels of hemoglobin concentration and albumin, and higher levels of CRP, IL-6, D-dimers and tPA. Our results showed an association between fibrinolytic/ endothelial cell function and increased inflammatory markers in CKD patients. The increased levels of Ddimer, tPA and inflammatory markers in CKD patients using a CVC, led us to propose a relationship between the type of VA chosen for HD, and the risk of thrombogenesis.

Oxidative stress in cyclosporine-induced hypertension: evidence of beneficial effects or tolerance development with nitrate therapy.

The aim of this study was to evaluate the effect of cyclosporine (CsA) on oxidative stress as well as the use of a nitric oxide (NO) donor, the organic nitrate isosorbide-5-mononitrate (Is-5-Mn), to prevent or reverse CsA-induced toxicity, namely on the vascular NO-cGMP pathway or on oxidative equilibrium. The following rat groups (n = 8) were tested: (1) a control group; (2) the CsA group (5 mg/kg/d for 7 weeks); (3) the Is-5-Mn group (150 mg/kg/d, twice a day for 7 weeks); (4) the preventive group (Is-5-Mn + CsA) treated for 2 weeks with Is-5-Mn only, and thereafter with both drugs for 7 weeks; (5) the curative group (CsA + Is-5-Mn) beginning 7 weeks after CsA, and following thereafter with both drugs for 5 weeks. The following parameters were evaluated: aortic cNOS activity and cGMP content; plasma levels of lipid peroxidation (malondialdehyde [MDA] levels); antioxidant capacity (glutathione peroxidase [GPx] and superoxide dismutase [SOD] activities, total antioxidant status, and vitamins A, C, and E); and peroxynitrite formation (3-nitrotyrosine [3-NT] content). Is-5-Mn + CsA therapy showed, when compared with the CsA group, total prevention of CsA-induced NO and cGMP attenuation, and no relevant influence on antioxidant indices, as well as on MDA and 3-NT levels. However, when compared with this CsA group, the curative group (CsA + Is-5-Mn) showed NO-cGMP values only partially reversed, and an enhancement in lipid peroxidation (5.6 +/- 1.4 vs 12.78 +/- 3.63 mumol/L; P < .05) and in peroxynitrite formation (16.7% incidence of positives vs 83.3% incidence of positives). Our data suggested that nitrate therapy may provide a valid choice to prevent CsA-induced NO-cGMP decrease, without a negative influence on the oxidative equilibrium. However, when the local environment is adverse, as occurs after CsA therapy, Is-5-Mn seemed to enhance the CsA-induced oxidative stress, promoting even worse deleterious effects, probably through the generation of the cytotoxic ROS peroxynitrite.

Dual effect of nitrate therapy for cyclosporine-induced hypertension on vascular and platelet morphofunctional markers; an animal model.

The present study sought to evaluate the prevention and reversion effects of isosorbide-5-mononitrate (Is-5-Mn) on the development of hypertension (HT) and on the underlying vascular and platelet morphofunctional disturbances, using an animal model of cyclosporine (CsA)-induced HT. The following rat groups (n = 8) were tested: (1) a control group (orange juice, for 7 weeks); (2) the CsA group (5 mg/kg/d for 7 weeks); (3) the Is-5-Mn group (150 mg/kg/d, twice a day for 7 weeks); (4) the prevention group (Is-5-Mn + CsA) treated for 2 weeks with Is-5-Mn only and thereafter with both drugs for 7 weeks; (5) the curative group (CsA + Is-5-Mn) beginning 7 weeks after CsA and following thereafter with both drugs for 5 weeks. Blood pressure, lipid profile, vascular lesion, platelet aggregation and morphology, and platelet thromboxane A(2)/vascular prostacyclin equilibrium were evaluated. Is-5-Mn + CsA therapy prevented (systolic blood pressure [SBP]: 114.3 +/- 1.9 mm Hg, P < .001; diastolic blood pressure [DBP]: 97.0 +/- 3.3 mm Hg, P < .001) the CsA-induced HT (SBP: 146.2 +/- 4.5 mm Hg, P < .001; DBP: 124.9 +/- 4.5 mm Hg, P < .001 vs control: SBP: 111.6 +/- 0.7 mm Hg; DBP: 94.6 +/- 1.0 mm Hg), as well as the vascular lesion and the platelet morphofunctional disturbances. The curative group did not show attenuated CsA-induced BP increase; it showed further enhancement of the HT effect (SBP: 159.7 +/- 5.5 mm Hg, P < .05; DBP: 132.8 +/- 2.8 mm Hg), as well as worsened vascular lesions and platelet function, namely a disruption in the TXA(2)/PGI(2) equilibrium. Our data suggested that Is-5-Mn therapy may be a valid choice to prevent the morphofunctional changes associated with CsA-induced HT, when used as a preventive therapy. A careful evaluation of the impact of nitrate therapy should be considered, particularly the negative effect on cardiovascular hemodynamics, when considering its use after previous CsA disturbances have been established.

Cyclosporine A-induced nephrotoxicity is ameliorated by dose reduction and conversion to sirolimus in the rat.

Side-effect minimization strategies to avoid serious side-effects of cyclosporine A (CsA), such as nephrotoxicity, have been mainly based on dose reduction and conversion to other putatively less nephrotoxic drugs, such as sirolimus (SRL), an inhibitor of the mammalian target of rapamycin. This study intended to evaluate the impact of protocols based on CsA dose reduction and further conversion to SRL on kidney function and lesions, based on serum, urine and renal tissue markers. The following 3 groups (n=6) were tested during a 9-week protocol: control (vehicle); CsA (5 mg/kg/day) and Red + Conv (CsA 30 mg/kg/day during 3 weeks + 3 weeks with CsA 5 mg/kg/day + SRL 1 mg/kg/day during the last 3 weeks). The following parameters were analysed: blood pressure, heart rate and biochemical data; serum and urine contents and clearances of creatinine, urea and neutrophil gelatinase-associated lipocalin (NGAL), as well as, glomerular filtration rate; kidney lipid peroxidation and clearance; kidney lesions were evaluated and protein expression was performed by immunohistochemistry. After the first 3 weeks of CsA (30 mg/kg/day) treatment animals showed body weight loss, hypertension, tachycardia, as well as, increased serum levels of non-HDL cholesterol, glucose, triglycerides, creatinine and urea, accompanied by decreased GFR and insulin levels. In addition, a significant increase in the expression of connective tissue growth factor, kidney injury molecule-1 (KIM-1), mammalian target of rapamycin, nuclear factor-κß1 and transforming growth factor-ß was found in the kidney, accompanied by extensive renal damage. The following 3 weeks with CsA dose reduction revealed amelioration of vascular and glomerular lesions, but without significant tubular improvement. The last 3 weeks with the conversion to sirolimus revealed high serum and urine NGAL contents but the CsA-evoked renal damage was substantially ameliorated, by reduced of connective tissue growth factor, mammalian target of rapamycin, nuclear factor-κß1 protein expression. In conclusion, CsA nephrotoxicity is dose dependent and moderate dysfunction could be ameliorated/prevented by SRL conversion, which could be pivotal for the preservation of kidney function and structure.

Dislipidemia and oxidative stress in mild and in severe psoriasis as a risk for cardiovascular disease.

Psoriasis is a common chronic and recurrent inflammatory skin disorder that has been associated with oxidative stress, abnormal plasma lipid metabolism and with high frequency of cardiovascular events. This prevalence seems to be related to the severity of psoriasis, as it occurs more frequently in patients presenting large areas of the body affected with psoriasis lesions. The aim of our work was to evaluate the development of oxidative stress and of dislipidemia in psoriasis, and to look for a correlation between their levels and worsening of psoriasis. We evaluated lipid profile, total antioxidant capacity, antioxidant vitamins A and E, and lipoperoxidation products. The study was performed in controls and in patients presenting mild and severe psoriasis. Patients presented risk changes in lipid profile (a rise in cholesterol (P<0.01), triglycerides (P<0.001), low density lipoprotein cholesterol (P<0.01), very low density lipoprotein cholesterol (P<0.01), apolipoprotein B (P<0.001) and lipoprotein(a) (P<0.001); and a reduction in high density lipoprotein cholesterol (P<0.001)), a rise in lipoperoxidation products (P<0.001) and a reduction in total antioxidant capacity (P<0.001) and in antioxidant vitamins A (P<0.001) and E (P<0.05). Moreover, we found that the worsening of psoriasis was associated with the enhancement of oxidative stress and of the lipid risk changes. Our data suggest that psoriasis patients must be considered as a group at risk for cardiovascular disease and that this risk seems to be higher in severe psoriasis. In addition, a possible benefit of an enriched diet or of a supplement of vitamins A and E in psoriasis patients should be further studied.

Iron as the key modulator of hepcidin expression in erythroid antibody-mediated hypoplasia.

Erythroid hypoplasia (EH) is a rare complication associated with recombinant human erythropoietin (rHuEPO) therapies, due to development of anti-rHuEPO antibodies; however, the underlying mechanisms remain poorly clarified. Our aim was to manage a rat model of antibody-mediated EH induced by rHuEPO and study the impact on iron metabolism and erythropoiesis. Wistar rats treated during 9 weeks with a high rHuEPO dose (200 IU) developed EH, as shown by anemia, reduced erythroblasts, reticulocytopenia, and plasmatic anti-rHuEPO antibodies. Serum iron was increased and associated with mRNA overexpression of hepatic hepcidin and other iron regulatory mediators and downregulation of matriptase-2; overexpression of divalent metal transporter 1 and ferroportin was observed in duodenum and liver. Decreased EPO expression was observed in kidney and liver, while EPO receptor was overexpressed in liver. Endogenous EPO levels were normal, suggesting that anti-rHuEPO antibodies blunted EPO function. Our results suggest that anti-rHuEPO antibodies inhibit erythropoiesis causing anemia. This leads to a serum iron increase, which seems to stimulate hepcidin expression despite no evidence of inflammation, thus suggesting iron as the key modulator of hepcidin synthesis. These findings might contribute to improving new therapeutic strategies against rHuEPO resistance and/or development of antibody-mediated EH in patients under rHuEPO therapy.

The in vitro and in vivo genotoxicity of isotretinoin assessed by cytokinesis blocked micronucleus assay and comet assay.

Isotretinoin is a retinoic acid frequently used in monotherapy or combined with narrow-band ultraviolet B (NBUVB) irradiation to treat patients with acne and psoriasis vulgaris. As both diseases need frequent and/or prolonged therapeutic interventions, the study of the genotoxicity of retinoids becomes important. Our aim was to study the genotoxic effects of isotretinoin alone or combined with NBUVB. In vitro studies were performed in the absence of S9 metabolic activation using blood from five healthy volunteers, incubated 72 h with isotretinoin (1.2-20 µM) (i.e., at concentrations usually achieved in blood with therapeutic doses as well as at higher concentrations). In vivo studies were also performed using blood from two patients with acne and three patients with psoriasis vulgaris treated with isotretinoin in monotherapy (8 or 20mg/day) or combined with NBUVB (20mg isotretinoin/day+NBUVB). The genotoxic effect was evaluated by the cytokinesis-blocked micronucleus and the comet assays. Our studies showed that isotretinoin alone was not genotoxic when tested in human lymphocytes in vitro and in vivo. There was no clear genotoxic effect in psoriatic patients treated with isotretinoin and NBUVB. The in vitro studies showed that isotretinoin induced apoptosis and necrosis in human lymphocytes at higher doses.

Erythrocyte damage in mild and severe psoriasis.

BACKGROUND: Psoriasis is a common chronic and recurrent inflammatory skin disorder. Oxygen metabolites and proteases released by activated inflammatory cells may induce oxidative and proteolytic damage to plasma constituents and red blood cells (RBCs). RBCs have a limited biosynthesis capacity and poor repair mechanisms. OBJECTIVES: To study RBCs as a potential cumulative marker of oxidative and proteolytic stress in psoriasis, and as a marker of worsening of the disease. METHODS: The study was performed in 70 patients with mild or severe psoriasis and in 40 control individuals. We evaluated total and differential leucocyte count and, as markers of leucocyte activation, plasma elastase and lactoferrin. Besides the basic RBC study (RBC count, haematocrit, haemoglobin concentration and haematimetric indices) we evaluated antioxidant defences (catalase, superoxide dismutase, glutathione peroxidase and selenium), osmotic fragility and reticulocyte count; in the RBC membrane we evaluated lipid peroxidation and susceptibility to lipid peroxidation, membrane fluidity, levels of cholesterol and phospholipids, membrane-bound haemoglobin, band 3 profile and levels of vitamin E; serum levels of bilirubin, total plasma antioxidant capacity, lipid profile and lipid peroxidation were also evaluated. RESULTS: Psoriasis patients showed a rise in leucocytes, mainly neutrophils, which was associated with a rise in elastase and lactoferrin. Patients had a reduced RBC count, antioxidant defences and membrane fluidity, elevated membrane lipid peroxidation, membrane-bound haemoglobin, osmotic fragility and reticulocyte count, and a different band 3 profile. Most of these modifications were enhanced in severe psoriasis. CONCLUSIONS: In summary, our data show that the RBCs are at a lower number in psoriasis patients, and present several changes denoting an enhanced damage and/or ageing process, which seem to be strongly connected with neutrophil activation, oxidative stress and worsening of psoriasis.