Enrica Berio

17β-estradiol upregulates oxytocin and the oxytocin receptor in C2C12 myotubes

Background The endocrinology of skeletal muscle is highly complex and many issues about hormone action in skeletal muscle are still unresolved. Aim of the work is to improve our knowledge on the relationship between skeletal muscle and 17β-estradiol. Methods The skeletal muscle cell line C2C12 was treated with 17β-estradiol, the oxytocin peptide and a combination of the two hormones. The mRNA levels of myogenic regulatory factors, myosin heavy chain, oxytocin, oxytocin receptor and adipogenic factors were analysed in C2C12 myotubes. Results It was demonstrated that C2C12 myoblasts and myotubes express oxytocin and its receptor, in particular the receptor levels physiologically increase in differentiated myotubes. Myotubes treated with 17β-estradiol overexpressed oxytocin and oxytocin receptor genes by approximately 3- and 29-fold, respectively. A decrease in the expression of fatty acid binding protein 4 (0.62-fold), a fat metabolism-associated gene, was observed in oxytocin-treated myotubes. On the contrary, fatty acid binding protein 4 was upregulated (2.66-fold) after the administration of the combination of 17β-estradiol and oxytocin. 17β-estradiol regulates oxytocin and its receptor in skeletal muscle cells and they act in a synergic way on fatty acid metabolism. Discussion Oxytocin and its receptor are physiologically regulated along differentiation. 17β-estradiol regulates oxytocin and its receptor in skeletal muscle cells. 17β-estradiol and oxytocin act in a synergic way on fatty acid metabolism. A better understanding of the regulation of skeletal muscle homeostasis by estrogens and oxytocin peptide could contribute to increase our knowledge of muscle and its metabolism.

Effects and detection of Nandrosol and ractopamine administration in veal calves

The present study describes different effects of the selective androgen receptor modulator (SARM) nandrolone phenylpropionate (Nandrosol) and the β-agonist ractopamine administration in veal calves, and it investigates different strategies applied to trace these molecules. Morphological changes of gonads and accessory glands attributed to androgen effects, such as testicular atrophy, seminiferous tubule diameter reduction and hyperplasia of prostate epithelium, were detected, although SARMs are not described to cause these lesions. The gene expression analysis showed an anabolic activity of Nandrosol in Longissimus dorsi muscle, where myosin heavy chain (MYH) was significantly up-regulated. An IGF1 increase was weakly significant only in Vastus lateralis muscle. In conclusion, the anatomo-histopathological observations and the MYH mRNA up-regulation in Longissimus dorsi muscle confirm the androgenic treatment in experimental animals. The biosensor assay was not enough sensitive to detect residues in urines and only the direct chemical analysis of urine samples confirmed both β-agonist and SARM treatment.

Diagnosis of canine gastric adenocarcinoma using squash preparation cytology.

Adenocarcinoma is the most common gastric tumour in dogs. Clinical signs and laboratory results are often non-specific, with histopathological examination of gastric biopsies being required to reach a definitive diagnosis. Use of cytology would potentially shorten the time to diagnosis and allow early interventional measures to be implemented. However, there are relatively few studies of the cytological features of gastric samples. The present study was designed to investigate whether cytology might be useful for diagnosis of canine gastric adenocarcinomas and to evaluate the performance of squash preparation cytology for this purpose. Squash preparations of gastric biopsies from 94 dogs were reviewed to determine the presence or absence of specific cytological features associated with adenocarcinomas and to compare findings with the results of histopathological examination of gastric biopsies. The presence of signet ring cells, microvacuolation, cellular pleomorphism and single cell distribution of epithelial cells were positively associated with a diagnosis of gastric adenocarcinoma. Combined evaluation (parallel testing) for the presence of signet ring cells and microvacuolation demonstrated excellent results for recognition of adenocarcinomas. Cytological examination of squash preparations from gastric biopsies and identification of signet ring cells and cytoplasmic vacuolation can allow rapid and reliable diagnosis of canine gastric adenocarcinomas.