Effects of darbepoetin-alpha on plasma pro-inflammatory cytokines, anti-inflammatory cytokine interleukin-10 and soluble Fas/Fas ligand system in anemic patients with chronic heart failure

Pro-inflammatory cytokine over-expression may be implicated to the pathogenesis of anemia in chronic heart failure (CHF) through the suppression of bone marrow erythropoiesis. Erythropoietin administration has anti-inflammatory and anti-apoptotic properties in experimental CHF models and improves exercise capacity in anemic CHF patients. The present study investigates the effects of recombinant human erythropoietin analogue darbepoetin-α on circulating pro-inflammatory cytokines and soluble Fas/soluble Fas ligand system in patients with CHF and anemia. Forty-one CHF patients (NYHA class: II–III; left ventricular (LV) ejection fraction (EF) <40%; hemoglobin <12.5 g/dl; serum creatinine <2.5 mg/dl) were randomized to receive either 3-month darbepoietin-α at 1.5 μg/kg every 20 days plus iron orally (n = 21) or placebo plus iron orally (n = 20). LV systolic function, plasma B-type natriuretic peptide (BNP), inflammatory markers (TNF-α, IL-6, CRP), anti-inflammatory cytokine IL-10, endothelial adhesion molecules (soluble ICAM-1 and VCAM-1) and soluble apoptosis mediators (soluble Fas, soluble Fas ligand), and 6-min walking distance were assessed at baseline and 3 months post-treatment. In darbepoetin-α treated patients, plasma BNP (451 (62-2770) from 802 (476-4440) pg/ml, p = 0.002), IL-6 (6.5 ± 4.7 from 10.5 ± 7.8 pg/ml, p = 0.013) and soluble Fas ligand (53.2 ± 16.6 from 59.2 ± 17.9 pg/ml, p = 0.023) decreased significantly, while LVEF (32 ± 6 from 26 ± 6%, p < 0.001), hemoglobin (12.8 ± 1.4 from 10.9 ± 1.0 g/dl, p < 0.001) and 6-min walked distance (274 ± 97 from 201 ± 113 m, p < 0.01) increased significantly. No significant changes were observed in the placebo arm, except for a worsening in 6-min walked distance (p = 0.044). In conclusion, darbepoetin-α reduces circulating pro-inflammatory cytokine IL-6 and apoptotic mediator soluble Fas ligand in CHF patients with anemia, with a parallel improvement of cardiac performance and exercise capacity.     

Prophylaxis with mesna prevents oxidative stress induced by ischemia reperfusion in the intestine via inhibition of nuclear factor-kappaB activation

Background and Aim: Mesna (2‐mercaptoethane‐sulfonate) has been shown to attenuate oxidative injury induced by ischemia reperfusion (I/R) in the kidneys, the liver, and the intestine; however, its mechanism of action has not been fully elucidated. We sought to determine a prophylactic admininstration schedule of mesna that would confer optimal antioxidant protection on the intestinal mucosa following I/R and to investigate whether mesna's action is mediated via inhibition of nuclear factor‐κB (NF‐κB) activity. Methods: Wistar rats were subjected to one of the following: (a) induction of 30 min ischemia followed by 60 min reperfusion (I30/R60) of the intestine, (b) pretreatment with intraperitoneal or oral mesna at various time‐ and dose‐ administration schedules plus I30/R60, (c) sham operation, (d) no operation (controls), or (e) oral mesna alone. At the end of the reperfusion period or at various time points after mesna alone administration, the oxidative state of the intestinal mucosa was assessed in terms of glutathione to glutathione disulfide ratio, malondialdehyde concentration, and superoxide dismutase activity. In addition, NF‐κB activity in the intestinal mucosa was assessed immunohistochemically in the oral mesna plus I/R and in the oral mesna alone groups. Results: Sham operation caused mild stress, while I/R caused substantial oxidative stress in the intestinal mucosa. Mesna pretreatment had an antioxidant effect which varied from attenuation to prevention of oxidative stress. Over the two routes of administration, the oral proved to be more effective and had a time‐ and dose‐ dependent effect. The antioxidant action of mesna was not related to enhancement of the intestinal mucosa oxidative state. Furthermore, I/R induced NF‐κB activation in the intestinal mucosa which was inhibited by mesna pretreatment. In the absence of oxidative damage, mesna led to downregulation of activated NF‐κB. Conclusions: Prophylaxis with mesna prevents oxidative stress induced by I/R in the intestine via inhibition of NF‐κB activation.     

Incremental value of pulse wave velocity in the determination of coronary microcirculatory dysfunction in never-treated patients with essential hypertension

BACKGROUND: Coronary microcirculation is disturbed in essential hypertension. We investigated whether arterial stiffness determines coronary flow reserve (CFR) in hypertensive patients. METHODS: We examined 100 never-treated hypertensives and 20 healthy controls. We measured (i) carotid-to-femoral pulse wave velocity (PWV); (ii) Systolic (V (s)) and diastolic (V (d)) coronary flow velocity, time integral (V (TI)-V (d)) of diastolic velocity and CFR after adenosine by transthoracic echocardiography; (iii) ratio of E wave from mitral inflow to Em of mitral annulus, as an index of left ventricular (LV) diastolic pressures using tissue Doppler; (iv) carotid intima-media thickness (IMT), as an index of vascular damage; and (v) 24-h blood pressure parameters using ambulatory blood pressure monitoring. RESULTS: Patients had abnormal PWV, IMT, E/Em, resting V (d)/V (s), and CFR than controls (P < 0.05). In hypertensives, PWV was related to abnormal IMT and E/Em which in turn were related to reduced CFR (P < 0.05). PWV and E/Em were independent determinants of CFR and V (d)/V (s) (P < 0.05) in hypertensives. When added to a model including age, sex, smoking, LV mass (LVM), heart rate, 24-h systolic blood pressure (SBP), and E/Em, PWV had an incremental value in the determination of CFR (r (2) change from 0.25 to 0.46, P < 0.01). PWV >10.7 m/s predicted a CFR <2 with 79 and 75% and a CFR <2.6 with 83 and 82% sensitivity and specificity, respectively, using adjusted-receiver operating characteristic curve (ROC) analysis. CONCLUSIONS: Elevated LV diastolic compressive forces on coronary microcirculation and the presence of generalized vascular damage may explain the association between PWV and CFR. PWV has an incremental value in the determination of impaired coronary microcirculation in hypertensive patients.     

Increased incidence of iron deficiency anemia secondary to inadequate iron intake in institutionalized,young patients with cerebral palsy

We observed high incidence of anemia in patients with cerebral palsy sheltered in a specialized institution in Thessaloniki, Greece. Therefore, we decided to investigate its cause. We studied 108 patients, and assessed complete blood cell count, peripheral blood smear, serum iron, ferritin, folate, B12 and the presence of hemoglobin or parasites in the stools. In all cases, anemia was hypochromic and microcytic. Approximately 33% of patients suffered from hypochromic anemia, whereas 38% were iron deficient. There was no statistical difference in the incidence of iron deficiency between different age groups. All tests for fecal occult blood or intestinal parasites were negative. Folic acid and B12 levels were within normal range in all cases. We also found that 87 and 95.6% of patients on liquid diet were anemic and iron deficient, respectively, compared to only 18.8 and 22.3% of patients on normal diet. The high incidence of anemia was attributed to iron deficiency which was secondary to inadequate iron intake and decreased iron absorption. Thus, it would not be irrational to consider iron supplementation as the first measure in such patients and postpone endoscopic procedures for a later stage, unless there are clinical or laboratory findings (such as fecal occult blood) suggestive of gastrointestinal blood loss.     

Dental pulp stem cells in chitosan/gelatin scaffolds for enhanced orofacial bone regeneration

Objective

Biomimetic chitosan/gelatin (CS/Gel) scaffolds have attracted great interest in tissue engineering of several tissues. However, limited information exists regarding the potential of combining CS/Gel scaffolds with oral cells, such as dental pulp stem cells (DPSCs), to produce customized constructs targeting alveolar/orofacial bone reconstruction, which has been the aim of the present study.

Dopaminergic and serotonergic modulation of persistent behaviour in the reinforced spatial alternation model of obsessive–compulsive disorder

RATIONALE: We have proposed rewarded T-maze alternation as a model of obsessive-compulsive disorder (OCD): the serotonin agonist m-chlorophenylpiperazine (mCPP) increments persistence therein, while chronic pretreatment with selective serotonin reuptake inhibitor (SSRI fluoxetine) but not benzodiazepine or desipramine abolishes mCPP effects. However, we noted that acute SSRI administration also causes transient persistence increase, counteracted by mCPP pretreatment. OBJECTIVES: This study (a) further explores the cross-tolerance between fluoxetine and mCPP and (b) extends the model by investigating its sensitivity to dopaminergic manipulations (D2, 3 agonism--quinpirole). MATERIALS AND METHODS: In both experiments, baseline and drug testing were carried out under daily T-maze alternation training. Exp. 1: Matched group (n = 8) pairs of rats received one of the following 20-day pretreatments (daily intraperitoneal administration): (1) saline, (2) low-dose fluoxetine (2.5 mg/kg), (3) low-dose mCPP (0.5 mg/kg) or (4) combined fluoxetine + mCPP. One group per pretreatment then received a 4-day challenge with high-dose fluoxetine (10 mg/kg), the other with high-dose mCPP (2.5 mg/kg). Exp. 2: One group (n = 12) of rats received 20-day treatment with saline, another with quinpirole (0.5 mg/kg). RESULTS: Exp. 1: Saline and low-dose mCPP- or fluoxetine-pretreated animals showed significant persistence increases under both challenges, while combined low-dose fluoxetine + mCPP pretreatment afforded full protection from either challenge. Exp. 2: Quinpirole significantly increased directional persistence after 13 administration days. CONCLUSIONS: These results establish the sensitivity of the rewarded alternation OCD model to D2, 3 receptor activation, thereby extending its profile of pharmacological isomorphism with OCD. Furthermore, they suggest a common mechanism of action of an SSRI and a serotonin agonist in the control of directional persistence.