Recombinant human erythropoietin (rEpo) is being used with increasing frequency by endurance athletes to improve aerobic potential. Although rEpo administration has been banned by the International Olympic Committee, no methods are available to unequivocally detect its abuse in sports. Prompted by these considerations, we evaluated the main hematological and biochemical modifications measured in the blood of 18 volunteers upon rEpo administration. Different rEpo regimens, iron, folic acid, and vitamin B12 administration did not significantly modify the percentage increase in hematocrit. However, a significant decrease in circulating ferritin (fr) and an increase in the soluble transferrin receptor (sTfr) were not found in athletes receiving low (30 IU/kg) doses of rEpo. Thus, an increase in the sTfr/fr ratio cannot be used as an indicator of rEpo abuse, at least when the hormone is administered at low concentrations. In contrast, the amounts of beta-globin mRNA detected by quantitative competitive (RT)-PCR in whole blood samples significantly increased above the threshold levels in all of the treatments investigated. Taken together, these data suggest that hematocrit value, reticulocyte count, soluble transferrin receptor content, and concentration of beta-globin mRNA, when included in a new multiparametric formula, can detect rEpo abuse in 57.5% of the samples examined with a confidence interval of 99.99%. Thus, the method reported in this paper could significantly improve the tests currently available, which in similar experiments allowed the detection of rEpo abuse in only 7.6% of the samples examined.

Adolescent↗

PubMedDate not supplied

Modulation of ICAM-1 expression in ECV304 cells by macrophage-released cytokines.

Transendothelial leukocyte trafficking during inflammation requires the expression of adhesion molecules such as human intercellular adhesion molecule-1 (ICAM-1). ICAM-1 is constitutively expressed on the surface of endothelial cells and its levels increase in response to a variety of inflammatory mediators, including cytokines. Monocyte/macrophage cells play a crucial role in this context because, upon stimulation, they release proinflammatory cytokines which are responsible for the upregulation of adhesion molecules in endothelial cells. In the present study we investigated whether the modulation of macrophage activation and cytokine release is able to modulate ICAM-1 expression in endothelial cells. Dexamethasone was selectively delivered to macrophages by means of a red blood cell-mediated delivery system. Subsequent stimulation of macrophages by lipopolysaccharide (LPS) was found to inhibit NF-kB activation and tumor necrosis factor-alpha (TNF-alpha) release [R. Crinelli, A. Antonelli, M. Bianchi, L. Gentilini, S. Scaramucci, and M. Magnani (2000) Blood Cells Mol. Dis. 26, 211-222]. Incubation with conditioned medium derived from LPS-stimulated macrophages receiving dexamethasone resulted in a 45% inhibition of ICAM-1 mRNA expression in ECV304 cells. In the same experimental system this reduced ICAM-1 expression was paralleled by a reduced NF-kB DNA binding activity and a twofold higher level of IkB(alpha) in the cytosol of endothelial cells. Activation of ICAM-1 expression in ECV304 cells by macrophage-conditioned medium is not due to IFN-gamma stimulation since STAT-1 DNA binding remained unchanged. Furthermore, treatment of the macrophage-conditioned medium with a TNF-alpha-inactivating antibody resulted in the complete abrogation of induced ICAM-1 expression. These results suggest that TNF-alpha is the main cytokine released by LPS-stimulated macrophages able to promote ICAM-1 gene expression in endothelial cells. Modulation of the NF-kB activation pathway in macrophages by targeted delivery of dexamethasone could potentially be used as a therapeutic strategy with which to inhibit the expression of ICAM-1 in endothelial cells.

Anti-Inflammatory Agents↗

PubMedDate not supplied

Antidepressant drugs and experimental inflammation.

There are strong indications from this brief survey that the anti-inflammatory action of antidepressant drugs is involved in their well documented analgesic effect. In particular, the experimental data reported here contribute to explain the reduction of pain observed after the acute administration of antidepressants in clinical conditions. A better understanding of the mechanisms underlined should lead to improved therapies for pain, and to new compounds for the treatment of inflammation.

Animals↗

PubMedDate not supplied

Unexpected lower prevalence of HBsAg in diabetics than in controls. (A study on 2,465 patients).

Serum samples from 2,465 diabetics were examined by radioimmunoassay for HBsAg, anti-HBs and anti-HBc at the Centro Antidiabetico of the Ospedale Maggiore di Lodi; during the same period, the same tests were carried out on serum samples from 2,176 control subjects, who had been admitted to the surgical, casualty and obstetrical departments for reasons that had nothing whatsoever to do with any form of liver disease. The ages of the two groups ranged from 6 to 90 years. The diabetics were divided into three groups; insulin-dependent, non-insulin-dependent and diabetics treated with insulin for diabetic complications. The overall frequency of HBsAg in the various groups of diabetics was 3.5%, while in the controls it was 6.1% (p less than 0.001). In the group of young insulin-dependent diabetics, the frequency was 1.7%, as compared to 6.9% for the controls in the same age group (p less than 0.05). In the group of patients treated with insulin for diabetic complications, the frequency increased to 11.5%, while for the controls in the same age group it was 5.5%. The levels of HBsAg were practically the same in the diabetics and in the controls, whereas the level of anti-HBc was higher in the diabetics: 55.6% compared to 50% (p less than 0.005). This last result indicates that the chances of hepatitis B virus infection were greater for the diabetics than for the controls. Diabetics, and especially those insulin-dependent are, therefore, believed to possess a greater capacity of resistance through their T cell-mediated immune response to the hepatitis B virus.

Adolescent↗

PubMedDate not supplied

Cysteamine protection of SCEs induced by UV and fluorescent light.

CHO cells were grown for 36 h in the presence of BUDR. 12 h before harvesting, the cells were irradiated with UV or with fluorescent (FL) light. Part of the cultures were treated with cysteamine (Cys) during irradiation. Metaphase spreads were stained by the Hoechst-plus-Giemsa method, and the frequency of SCEs per chromosome was determined in second-mitosis cells. The basal frequency of SCEs (1.07 +/- 0.073) was not increased by Cys treatment (1.15 +/- 0.048). On the other hand, UV and FL induced a 3-4-fold increase in the frequency of exchanges (4.18 +/- 0.2 and 3.32 +/- 0.12 resp.). Cys, when present during irradiation, markedly reduced the frequency of UV- and FL-induced SCEs (2.7 +/- 0.14 and 2.29 +/- 0.11 resp.). It is assumed that Cys prevents the formation of radiation-induced breakages in the BUDR-substituted DNA. The residual increase over the basal levels of SCEs which remains after the treatment with Cys may be due to the persistence of some open breaks, to the presence of protein-DNA crosslinking, or to the combined action of both types of lesion.

Animals↗

PubMedDate not supplied

Central nervous system neuropeptides after peripheral nerve deafferentation.

Beta-endorphin, Met-enkephalin, substance P, somatostatin and dynorphin concentrations were evaluated in right and left brain areas, and in cervical, thoracic, and lumbosacral spinal cord of rats that underwent section of either the right, the left, both sciatic nerves, the right brachial plexus, the saphenous, or the sural nerve. With all the surgeries, beta-endorphin concentrations decreased significantly in all brain areas with the exception of the striatum where they did not change. By contrast Met-enkephalin increased in all brain areas and in the spinal cord tracts interested by the lesions. The other peptides were always unaffected. The changes in the concentrations of the neuropeptides were observed starting twenty-four hours after surgery and lasted for at least four months. We did not find a lateralization in the brain peptide concentrations of either sham operated or unilaterally deafferentated rats. Moreover, the treatment with serotoninergic agents normalized the concentrations of beta-endorphin, suggesting a role of the serotoninergic system in the decrease of the peptide that follows the lesion of peripheral nerves.

Animals↗