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Ravi Sankar, B.
- Serum Dihydrotestosterone is a Major Determinant of Bone Mineral Density in Men
Abstract Views :234 |
PDF Views:0
Authors
R. llangovan
1,
M. Balaganesh
1,
S. Sittadjody
1,
R. Sivakumar
1,
M. Sridhar
1,
R. C. Vignesh
1,
B. Ravi Sankar
1,
J. Arunakaran
1,
K. Balasubramanian
1,
M. Michael Aruldhas
1,
N. Srinivasan
1
Affiliations
1 Department of Endocrinology, Dr. ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai - 600 113, IN
1 Department of Endocrinology, Dr. ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai - 600 113, IN
Source
Journal of Endocrinology and Reproduction, Vol 10, No 1 (2006), Pagination: 56-58Abstract
In the present investigation, 100 osteoporotic men with 100 age-matched normal were studied for serum sex steroids, parathyroid hormone (PTH), thyroid hormone (T3), cytokines and bone turnover markers. Serum dihydrotestosterone (DHT) was significantly decreased in osteoporotic men compared with normal. In osteoporotic men, there was a significant increase in serum interleukin (IL)-lalpha. A marked increase in bone formation marker, serum osteocalcin (OCN) and bone resorption marker, serum tartrate-resistant acid phosphatase (TRAP) reflects high bone turnover in osteoporotic men. In conclusion, the present findings point out an important role of DHT in maintaining BMD in men. A strong positive correlation of serum DHT with BMD offers new perspectives in understanding the role of non-aromatizable androgen in the regulation of bone metabolism in men.Keywords
BMD, Cytokines, DHT.
- Gestational Exposure to Di(2-Ethylhexyl)Phthalate Modifies the Expression Pattern of Genes Controlling Thyroid Hormone Biosynthesis in Puberal Rat Progeny
Abstract Views :270 |
PDF Views:2
Authors
V. Sambavi
1,
M. M. Aruldhas
1,
S. Suganya
1,
P. Rajesh
1,
E. Suthagar
1,
A. K. Navin
1,
N. Shobana
1,
B. Ravi Sankar
1,
R. Ilangovan
1
Affiliations
1 Department of Endocrinology, Dr ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai - 600113, Tamil Nadu, IN
1 Department of Endocrinology, Dr ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai - 600113, Tamil Nadu, IN
Source
Journal of Endocrinology and Reproduction, Vol 20, No 2 (2016), Pagination: 92-101Abstract
Di(2-ethylhexyl) phthalate (DEHP), a plasticiser, is known to disrupt thyroid functions but the underlying molecular mechanism remains obscure. The present study was conducted testing the hypothesis that gestational exposure to DEHP may modify the expression of specific genes controlling biosynthesis and action of thyroid hormones in the male progeny at puberal age. Pregnant rats were administered with DEHP [1, 10 and 100 mg (in olive oil)/Kgb.wt./day] from embryonic day 9 to 21 through oral route. The pups were sacrificed on post-natal day 60. Enzyme Immuno Assay (EIA) revealed a dose-dependent decrease in serum 3,5,3’ triiodothyronine (T3) and L-thyroxine (T4) titres in DEHP-treated rats. Real-time RT-PCR and western blot analyses of thyroidal genes revealed decreased expression level of sodium/iodide symporter (Nis) and thyroid hormone receptor α (Trα), whereas the expression of thyroid stimulating hormone receptor (Tshr), thyroid hormone receptor β (Trβ) and pendrin (Pds) increased. While western blot detection showed decreased expression level of thyroperoxidase (Tpo), RTPCR data pointed out augmented expression. Western blot detection of transcriptional factors showed decreased expression levels of fork-headbox e1 (Foxe1) and haematopoietically expressed homeobox (Hhex), whereas thyroid transcription factor-1 (Ttf-1) and paired-box domain 8 (Pax8) increased. Our study demonstrates, for the first time, that gestational exposure to DEHPaffects the expression of genes controlling thyroid hormone synthesis in puberal rat progeny, and the hypothyroid state in these rats may be linked to decreased expression of Nis, Tpo, Foxe1 and Hhex.Keywords
Pendrin, Sodium/Iodide Symporter, Thyroperoxidase, Thyrotrophin Receptor, Haematopoietically Expressed Homeobox.References
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