Alpha-2 macroglobulin in Alzheimer's disease: a marker of neuronal injury through the RCAN1 pathway.

Preclinical changes that precede the onset of symptoms and eventual diagnosis of Alzheimer's disease (AD) are a target for potential preventive interventions. A large body of evidence suggests that inflammation is closely associated with AD pathogenesis and may be a promising target pathway for such interventions. However, little is known about the association between systemic inflammation and preclinical AD pathophysiology. We first examined whether the acute-phase protein, alpha-2 macroglobulin (A2M), a major component of the innate immune system, was associated with cerebrospinal fluid (CSF) markers of neuronal injury in preclinical AD and risk of incident AD in the predictors of cognitive decline among normal individuals (BIOCARD) cohort. We find that A2M concentration in blood is significantly associated with CSF concentrations of the neuronal injury markers, tau and phosphorylated tau, and that higher baseline serum A2M concentration is associated with an almost threefold greater risk of progression to clinical symptoms of AD in men. These findings were replicated in the Alzheimer's Disease Neuroimaging (ADNI) study. Then, utilizing a systems level approach combining large multi-tissue gene expression datasets with mass spectrometry-based proteomic analyses of brain tissue, we identified an A2M gene network that includes regulator of calcineurin (RCAN1), an inhibitor of calcineurin, a well-characterized tau phosphatase. A2M gene and protein expression in the brain were significantly associated with gene and protein expression levels of calcineurin. Collectively these novel findings suggest that A2M is associated with preclinical AD, reflects early neuronal injury in the disease course and may be responsive to tau phosphorylation in the brain through the RCAN1-calcineurin pathway.

Celecoxib for the treatment of mild-to-moderate depression due to acute brucellosis: a double-blind, placebo-controlled, randomized trial.

WHAT IS KNOWN AND OBJECTIVE: Depression is a debilitating complication of brucellosis and how best to treat this is a matter of debate. Inflammatory processes are involved in the pathogenesis of both brucellosis and depression. Therefore, we hypothesized that celecoxib could be beneficial for the treatment of depression due to brucellosis. METHODS: Forty outpatients with depression due to brucellosis with a Hamilton Depression Rating Scale score (HDRS) <19 participated in a randomized, double-blind, placebo-controlled trial and underwent 8 weeks of treatment with either celecoxib (200 mg bid) or placebo as an adjunctive to antibiotic therapy. Patients were evaluated using HDRS at baseline and weeks 4 and 8. RESULT AND DISCUSSION: Repeated-measures analysis demonstrated significant effect for time × treatment interaction on the HDRS score [F (1·43, 57·41) = 37·22, P < 0·001]. Significantly greater response to treatment occurred in the celecoxib group than in the placebo group at the study end [10 patients (50%) vs. no patient (0%), respectively, P < 0·001]. No serious adverse event was observed. WHAT IS NEW AND CONCLUSION: Celecoxib is a safe and effective treatment for depression due to brucellosis when compared with placebo.

[Effect of erythropoietin therapy on alpha receptor density in chronic dialysis patients]. / Einfluss einer Erythropoetintherapie auf die alpha-Adrenozeptoren-Dichte bei chronischen Dialysepatienten.

The effect of a six months therapy with human recombinant erythropoietin (rHu-EPO) on blood pressure and on several parameters of sympathetic nervous activity was studied in chronic haemodialysis patients in a controlled and randomized trial in order to gain further insight into the mechanism of rHu-EPO-induced blood pressure elevation. Treatment was started at a dose of 3 X 80 IE/kg/week in eleven patients aiming to increase the initial hemoglobin concentration (7.0 +/- 0.3 [SEM] g%) to 10.0 g% by dose adjustments, while another untreated eleven patients served as a control group. Diastolic arterial pressure measured before and after haemodialysis increased on rHu-EPO treatment by 7 and 8 mm Hg respectively (p less than 0.05). Plasma noradrenaline concentration was increased (p less than 0.05) after the six months treatment period in the presence of unchanged dry weights. Conversely platelet alpha 2-adrenoceptor density (3H-yohimbine binding) and the fraction of high affinity binding sites for alpha 2-agonists (3H-UK 14.304) decreased (p less than 0.01) along with a decrease in reactivity to exogenous noradrenaline (p less than 0.05). None of these parameters changed in the control group compared to pretreatment values. The results obtained demonstrate that increased plasma noradrenaline concentrations may participate in rHu-EPO induced blood pressure increases. The decrease in platelet alpha 2-adrenoceptor densities and the decrease in noradrenaline reactivity in the presence of increased plasma noradrenaline concentrations suggest an intact regulation of alpha 2-adrenoceptors in chronic haemodialysis patients on chronic rHu-EPO therapy.

Effect of erythropoietin on parameters of sympathetic nervous activity in patients undergoing chronic haemodialysis.

The effect of erythropoietin (rHu-EPO) on blood pressure and on parameters of sympathetic nervous activity of patients undergoing chronic haemodialysis treatment was evaluated in a controlled and randomized 6-months study. Both groups did not differ significantly at the onset of the study in terms of dialysis protocol, haematological parameters, blood chemistry, weight, blood pressure and parameters of sympathetic nervous activity. Haemoglobin increased from 7.0 +/- 0.3 g dl-1 to 10.0 +/- 0.3 g dl-1 by 6 months on rHu-EPO (n = 11) and remained constant in the control group (n = 11). After 6 months diastolic blood pressure was higher in the treatment group compared with the control group as well as compared with pretreatment values, whereas reactivity to exogenous noradrenaline and platelet alpha 2-adrenoceptor densities ([3H]-yohimbine- and [3H]-UK 14,304-binding sites) were lower. Plasma noradrenaline concentration increased during rHu-EPO compared with pretreatment values, while dry weights were unchanged during the study. The results demonstrate alterations of some parameters of sympathetic nervous activity during rHu-EPO-therapy which were absent in the control group.