Day 3 :
- CorticoSteroids
Session Introduction
Mohammad Yasin Mohammad
Middle East University
Jordan
Title: Biotransformation of some anabolic steroids by Rhizopus stolonifer
Biography:
Mohammad Yasin Mohammad is currently a professor at Middle East University, Jordan
Abstract:
Microorganisms have been used extensively for hydroxylation of anabolic steroids since their enzymes can catalyze reactions with high regio- and stereospecifity. Their ability to oxidize steroidal compounds has immense synthetic and commercial importance. Selected anabolic steroids (oxandrolone (1), mestanolone (2) and 17-methyl-1-testosterone (3)) were subjected to biotransformation using the plant pathogen fungus Rhizopus stolonifer. Oxandrolone (1) and mestanolone (2) are anabolic synthetic derivatives of testosterone that act on androgen receptors [1]. 17-Methyl-1-testosterone (3) is an anabolic synthetic derivative of mestanolone (2). Incubation of oxandrolone (1) with R. stolonifer yielded metabolites 4-6 , [2]. While incubation of mestanolone (2) and 17-methyl-1-testosterone (3) with R. stolonifer produced metabolites 7, 8 and 9, 10 , [3], respectively. Structures of compounds 4-10 were deduced through comparative spectroscopic studies with substrates 1-3. The stereochemistry in compounds 4-8 and 10 were determined by NOESY spectrum and single-crystal X-ray diffraction studies for metabolite 4 (Figure-4). Compounds 1 and 5 showed a significant β-glucuronidase inhibitory activity.
Isbel GarcÃa Figueredo
Institute of Oncology and Radiobiology
Cuba
Title: Testosterone, estrogen and insulin in the development of prostate cancer
Biography:
Isbel GarcÃa is a PhD student; she has a master degree in Laboratory Science, from Havana University of Cuba. She is a project leader of two projects, at the Institute of Oncology and Radiobiology: “Hormonal behavior in Prostate intraepithelial neoplasia and Cancer: Its role as tumor markers.†and, “New Urine Molecular Tumor Markers to Improve Prostate Cancer Diagnosisâ€. She has published 12 papers and has been proposed as a reviser in MEDWAVE magazine. She was a member of a scientific board of her institute for five years. She is also, an assistant professor of the Medicine Faculty “Manuel Fajardoâ€.
Abstract:
Introduction: Prostate cancer (PCa) is the second most frequently diagnosed cancer in men and the second leading cause of cancer death in the male. This phenomenon could be due to hormonal changes during aging. So in this conference we will briefly summarize the biochemistry of androgens, estrogens and insulin in relation to prostate cancer development and advanced phenotypes.
Background: In the elderly, the androgen levels drop significantly, whereas their estrogen levels remain unchanged or increased, making the estrogen to androgen ratio elevated in the aging prostate. There are also a relationship between different serum testosterone levels and intraprostatic androgen receptor fluxes, signaling efficiency and downstream physiological responses. In addition, we would like to point out that the epidemiological studies indicate a correlation between PCa and circulating estrogen levels, among different ethnic/racial groups with diverse PCa incidence. But some of them emphasize that low testosterone levels may actually be a marker of more-aggressive prostate cancer. The estrogens actions are mediated by estrogen receptors (ERs), alpha (α) and beta (β). The continuing controversy over the function of ERβs in prostate carcinogenesis could be due to variable expression levels of different ERβ isoforms in benign versus malignant tissues during different stages of the process. On the other hand, the insulin and its insulin growing factors had an essential role in prostate cancer carcinogenesis and in prostate cancer aggressive phenotype. Furthermore, the overexpression of insulin receptors (IRs) in prostate cancer and the association between IR expression or IR/IGF1R activation has been found in both stromal and epithelial prostate tissue compartments but changes with cancer progression that becoming an autocrine signal to it.
Conclusions: Until now, elucidating mechanisms of paracrine/steroid hormone-induced changes in cellular differentiation, proliferation, and gene expression, and carcinogenesis give us confusing results let us to know that he crosstalk between the hormonal milieus are essential for prostate cancer development.
Outcome/Impact: On the knowledge of the mechanisms involved in prostatic carcinogenesis.
Biography:
Gihane khalil was graduated from faculty of medicine, Alexandria University, Egypt at 1996, complete her PhD in Chemical pathology at 2007, she is an assistant professor of Chemical pathology since February 20013. She is director of Chemical Pathology Lab in Medical Research Institute ,Alexandria university. She has published more than 15 papers in International journals in the field of Diabetes, obesity and breast cancer.
Abstract:
Overweight and obesity are the leading causes for the development of multiple adverse metabolic effects. Retinol Binding Protein 4 (RBP4), a peptide secreted from adipocytes and hepatocytes, provides a new link between obesity and insulin resistance. The objective of this work is to determine RBP4 serum levels and evaluate its relationship with serum testosterone (T), serum estradiol (E2), E2/T ratio and insulin resistance in overweight and obese Egyptian men. The study included 65 men which were subdivided into (20 normal weight, 20overweight and 25 obese). Their mean age was (43.88±5.52). Serum RBP4 was measured by the enzyme linked immunosorbent assay. Serum RBP4 and E2/T ratio were significantly higher, while serum T was significantly lower in overweight and obese groups as compared with normal weight group. In all subjects, serum RBP4 correlated positively with BMI, waist circumference, waist-to-hip ratio (WHR), HOMA-IR, serum E2 and E2/T ratio. In contrast, it correlated negatively with quantitative insulin sensitivity check index (QUICKI) and serum T. In multiple linear regression analysis serum RBP4 was dependently associated with E2/T ratio. It could be concluded that serum RBP4 is elevated in overweight and obese as compared with normal weight subjects, and that the disturbance in E2/T ratio seem to affect RBP4 serum levels and insulin sensitivity in obese men.
Isbel GarcÃa Figueredo
Institute of Oncology and Radiobiology
Cuba
Title: Role of testosterone and estrogen in prostate cancer risk
Biography:
Isbel GarcÃa is a PhD student; she has a master degree in Laboratory Science, from Havana University of Cuba. She is a project leader of two projects, at the Institute of Oncology and Radiobiology: “Hormonal behavior in Prostate intraepithelial neoplasia and Cancer: Its role as tumor markers.†and, “New Urine Molecular Tumor Markers to Improve Prostate Cancer Diagnosisâ€. She has published 12 papers and has been proposed as a reviser in MEDWAVE magazine. She was a member of a scientific board of her institute for five years. She is also, an assistant professor of the Medicine Faculty “Manuel Fajardoâ€.
Abstract:
Aim: To identify if testosterone, estradiol and PSAT are related to the risk of developing prostate cancer.
Material and Methods: A case-control study was performed in 115 patients with benign prostatic hyperplasia (BPH), prostate cancer and controls, which underwent prostate surgery. The total PSA (TPSA), total testosterone (T) and estradiol (E) were quantified by IRMA kits, with biopsy as reference test. Multivariate logistic regression analysis was performed to evaluate the association with the presence of cancer.
Results: Although statistical differences between cancer patients and patients with BPH and those relative to the control (P <0.001), concerning the three markers, they did not show a high specificity. The T to TPSA ratio and E to TPSA ratio could discern between the three groups of patients with high sensitivity (100% and 94.12%, respectively) and specificity (91.53% and 81.58%, respectively). Multivariate analysis showed an increased risk of cancer in patients with levels of T<3 ng/mL, T to TPSA ratio <0.29 and E /TPSA <0.002642.
Discussion and Conclusions: The risk of prostate cancer is associated with low levels of T/PSAT ratio and E/TPSA ratio that increase the TPSA specificity. Showing ratios T/TPSA and E/TPSA had high sensitivity and specificity, so they could considered as prostate cancer risk predictors.
- Anabolic Steroids and Supplements