Athletic humans and horses: comparative analysis of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) expression in peripheral blood mononuclear cells in trained and untrained subjects at rest.

BACKGROUND: Horses and humans share a natural proclivity for athletic performance. In this respect, horses can be considered a reference species in studies designed to optimize physical training and disease prevention. In both species, interleukin-6 (IL-6) plays a major role in regulating the inflammatory process induced during exercise as part of an integrated metabolic regulatory network. The aim of this study was to compare IL-6 and IL-6 receptor (IL-6R) mRNA expression in peripheral blood mononuclear cells (PBMCs) in trained and untrained humans and horses. RESULTS: Nine highly trained male swimmers (training volume: 21.6 ± 1.7 h/wk in 10-12 sessions) were compared with two age-matched control groups represented by eight lightly trained runners (training volume: 6.4 ± 2.6 h/wk in 3-5 sessions) and nine untrained subjects. In addition, eight trained horses (training volume: 8.0 ± 2.1 h/wk in 3-4 sessions) were compared with eight age-matched sedentary mares. In humans, IL-6 mRNA levels in PBMCs determined by quantitative reverse transcription-polymerase chain reaction were significantly higher in highly trained subjects, whereas IL-6R expression did not differ among groups. In horses, transcripts of both IL-6 and IL-6R were significantly up-regulated in the trained group. CONCLUSIONS: Up-regulation of IL-6R expression in PBMCs in horses could reflect a mechanism that maintains an adequate anti-inflammatory environment at rest through ubiquitous production of anti-inflammatory cytokines throughout the body. These findings suggest that the system that controls the inflammatory response in horses is better adapted to respond to exercise than that in humans.

Rottlerin: a multifaced regulator of keratinocyte cell cycle.

In this study we showed that Rottlerin (also called Kamala or Mallotoxin), a natural product purified from Mallotus phillippinensis, is a potent suppressor of human keratinocytes (HaCaT cell line) proliferation. Following Rottlerin treatment, Thymidine incorporation into DNA and re-epithelialisation in a scratch wound model was decreased. At the molecular level, Rottlerin hampered the NFkB activation process, causing loss of cyclin D1 and promoting, in a PKCdelta-dependent pathway, ERK activation, which, in turn induced the cell cycle inhibitor p21 Cip1/Kip1. The NFkB-dependent drop in cyclin D1, along with the PKCdelta/ERK-dependent induction of p21 Cip1/Kip1, is responsible for growth arrest. These results open the way to further investigation on the Rottlerin therapeutic potential against keratinocyte hyper-proliferative disorders.

Differential expression of follistatin and FLRG in human breast proliferative disorders.

BACKGROUND: Activins are growth factors acting on cell growth and differentiation. Activins are expressed in high grade breast tumors and they display an antiproliferative effect inducing G0/G1 cell cycle arrest in breast cancer cell lines. Follistatin and follistatin- related gene (FLRG) bind and neutralize activins. In order to establish if these activin binding proteins are involved in breast tumor progression, the present study evaluated follistatin and FLRG pattern of mRNA and protein expression in normal human breast tissue and in different breast proliferative diseases. METHODS: Paraffin embedded specimens of normal breast (NB - n = 8); florid hyperplasia without atypia (FH - n = 17); fibroadenoma (FIB - n = 17); ductal carcinoma in situ (DCIS - n = 10) and infiltrating ductal carcinoma (IDC - n = 15) were processed for follistatin and FLRG immunohistochemistry and in situ hybridization. The area and intensity of chromogen epithelial and stromal staining were analyzed semi-quantitatively. RESULTS: Follistatin and FLRG were expressed both in normal tissue and in all the breast diseases investigated. Follistatin staining was detected in the epithelial cytoplasm and nucleus in normal, benign and malignant breast tissue, with a stronger staining intensity in the peri-alveolar stromal cells of FIB at both mRNA and protein levels. Conversely, FLRG area and intensity of mRNA and protein staining were higher both in the cytoplasm and in the nucleus of IDC epithelial cells when compared to NB, while no significant changes in the stromal intensity were observed in all the proliferative diseases analyzed. CONCLUSION: The present findings suggest a role for follistatin in breast benign disease, particularly in FIB, where its expression was increased in stromal cells. The up regulation of FLRG in IDC suggests a role for this protein in the progression of breast malignancy. As activin displays an anti-proliferative effect in human mammary cells, the present findings indicate that an increased FST and FLRG expression in breast proliferative diseases might counteract the anti-proliferative effects of activin in human breast cancer.

Changes in salivary cortisol and corticosteroid receptor-alpha mRNA expression following a 3-week multidisciplinary treatment program in patients with fibromyalgia.

The aim of the present study was to investigate the effects of a 3-week residential multidisciplinary non-pharmacological treatment program (including individually prescribed aerobic exercise and cognitive-behavioral therapy) on fibromyalgia symptoms and hypothalamic-pituitary-adrenal (HPA) axis function. Salivary and venous blood samples were collected from 12 female patients with fibromyalgia (age: 25-58) the day before and the day after the treatment period: saliva, eight times (every two hours from 0800 to 2200 h); venous blood, at 0800 h. Peripheral blood mononuclear cells (PBMC) were separated and analyzed for glucocorticoid receptor-alpha (GR-alpha) mRNA expression by semi-quantitative RT-PCR, while the salivary cortisol concentration was determined by RIA. At the same time, pain and aerobic capacity were evaluated. Aerobic capacity improved at the end of the treatment program. The slope of the regression of salivary cortisol values on sampling time was steeper in all patients after treatment, indicating that the cortisol decline was more rapid. Concomitantly, the area under the cortisol curve "with respect to increase" (AUC(i)) was higher and there was a significant increase in GR-alpha mRNA expression in PBMC. The number of positive tender points, present pain, pain area and CES-D score were significantly reduced after the treatment, while the pressure pain threshold increased at most of the tender points. Our findings suggest that one of the active mechanisms underlying the effects of our treatment is an improvement of HPA axis function, consisting in increased resiliency and sensitivity of the stress system probably related to stimulation of GR-alpha synthesis by the components of the treatment.

Influence of amalgam fillings on Hg levels and total antioxidant activity in plasma of healthy donors.

In order to evaluate the influence of specific factors on mercury (P-Hg) levels and antioxidant power (P-FRAP) in human plasma, 26 healthy donors were examined by a dentist, their plasma analyzed for Hg by atomic absorption spectrometry and for total antioxidant activity by FRAP method. Hg plasma concentration was found to be correlated with the number of amalgam fillings, suggesting that Hg released from fillings is a source of Hg in non-occupational exposed subjects. P-FRAP correlated negatively with P-Hg suggesting a pro-oxidant role of the Hg released from amalgam fillings. Though age by itself was not significantly correlated with P-FRAP, when considered together with P-Hg in multivariate analysis, it was found to be a major related cofactor. Multivariate analysis showed no influence of fish consumption or cigarette smoking on P-FRAP.

Prepro-endothelin-1 mRNA and its mature peptide in human appendix.

Because the precise immunopathological events occurring in appendicitis are not completely understood, possible local production of endothelin-1 (ET-1) in human appendix was investigated. We used immunohistochemistry and in situ hybridization to detect the presence, distribution, and phenotype of ET-1-positive cells and prepro-ET-1 (pp-ET-1) mRNA-expressing cells. ET-1-positive stromal cells and pp-ET-1 mRNA-expressing cells were detected with different distributions and relative frequencies in normal control appendix, histologically normal appendix, and inflamed appendix. Six of 20 histologically normal appendixes from patients with a clinical diagnosis of acute appendicitis had many ET-1-positive stromal cells and high pp-ET-1 mRNA expression, similar to inflamed appendix. Forty percent of the pp-ET-1 mRNA-expressing cells were neutrophils, and the other positive cells were mast cells and macrophages. We suggest that local production of ET-1 by neutrophils and other inflammatory cells could be a molecular sign of focal inflammation in histologically normal appendixes and that ET-1 could be implicated, with other cytokines, in the pathogenesis of appendicitis by inducing appendiceal ischemia through vasoconstriction.