Regucalcin expression in bovine tissues and its regulation by sex steroid hormones in accessory sex glands.

Regucalcin (RGN) is a mammalian Ca2+-binding protein that plays an important role in intracellular Ca2+ homeostasis. Recently, RGN has been identified as a target gene for sex steroid hormones in the prostate glands and testis of rats and humans, but no studies have focused on RGN expression in bovine tissues. Thus, in the present study, we examined RGN mRNA and protein expression in the different tissues and organs of veal calves and beef cattle. Moreover, we investigated whether RGN expression is controlled through sex steroid hormones in bovine target tissues, namely the bulbo-urethral and prostate glands and the testis. Sex steroid hormones are still illegally used in bovine husbandry to increase muscle mass. The screening of the regulation and function of anabolic sex steroids via modified gene expression levels in various tissues represents a new approach for the detection of illicit drug treatments. Herein, we used quantitative PCR, western blot and immunohistochemistry analyses to demonstrate RGN mRNA and protein expression in bovine tissues. In addition, estrogen administration down-regulated RGN gene expression in the accessory sex glands of veal calves and beef cattle, while androgen treatment reduced RGN gene expression only in the testis. The confirmation of the regulation of RGN gene expression through sex steroid hormones might facilitate the potential detection of hormone abuse in bovine husbandry. Particularly, the specific response in the testis suggests that this tissue is ideal for the detection of illicit androgen administration in veal calves and beef cattle.

Corticosteroid hormone receptors and prereceptors as new biomarkers of the illegal use of glucocorticoids in meat production.

Despite the European ban on the use of growth promoters in cattle, veterinary surveillance reports indicate that the illicit use of corticosteroids persists both alone and in combination with anabolic hormones and ß-agonists. Current control strategies should be informed by research into the effects of corticosteroids on bovine metabolism and improved through the development of specific, sensitive diagnostic methods that utilize potential molecular biomarkers of corticosteroid treatment. The actions of corticosteroids on target tissues are principally regulated by two receptors: the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR). The effects of these steroids are modulated by prereceptor enzyme-mediated metabolism: the two isoforms of the 11ß-hydroxysteroid dehydrogenase (11ß-HSDs) enzyme catalyze the interconversion between active glucocorticoids, such as cortisol, into inactive compounds, such as cortisone. This study aimed to determine whether the expression of the prereceptor system and of the corticosteroid receptors could be regulated in different target tissues by the administration of dexamethasone and prednisolone in cattle. It was observed that greater up-regulation of the GR and MR genes followed dexamethasone treatment in the muscle tissues than in the kidney, liver, and salivary glands; up-regulation of GR and MR expression following prednisolone treatment was higher in adipose tissue than in the other tissues. The thymus seemed to respond to dexamethasone treatment but not to prednisolone treatment. Both treatments significantly down-regulated 11ß-HSD2 gene expression in the adrenal tissues, but only dexamethasone treatment down-regulated 11ß-HSD2 expression in the bulbourethral and prostate glands. Together, these data indicate that the combination of GR, MR, and 11ß-HSD2 could provide a useful biomarker system to detect the use of illicit glucocorticoid treatment in cattle.

Pathology of the testicle and sex accessory glands following the administration of boldenone and boldione as growth promoters in veal calves.

Boldenone and its precursor Boldione are illegally used for anabolic purposes in humans, horses and cattle. To develop more effective policies and programs to maximize food security, Italian Public Health Services investigate all indicators capable of assisting the recognition of treated animals, and prioritize research and the formulation of action strategies for the promotion of healthy eating. Thus, an experimental administration of boldenone and boldione at anabolic dosages in veal calves was carried out to evaluate the changes in target organs by qualitative and semi-quantitative morphological analysis. The lesions resembled the effects already observed after the administration of androgen hormones to cattle. Main findings were represented by prostate hypersecretion, increased rate of apoptotic cells and decreased rate of Ki67 positive cells in the germ cell line of treated animals, particularly in boldione group and finally some new features like hypertrophy of the prostate urothelial cells.