Featured Research

from universities, journals, and other organizations

New understanding of male puberty

Date:
March 15, 2011
Source:
Monash University
Summary:
Scientists have uncovered a new understanding of how male puberty begins. The key to their findings lies with a protein known as SMAD3 and the rate at which it is produced.

Scientists from Monash University have uncovered a new understanding of how male puberty begins. The key to their findings lies with a protein known as SMAD3 and the rate at which it is produced.

Researchers, Associate Professor Kate Loveland and Dr Catherine Itman from the Faculty of Medicine, Nursing and Health Sciences have discovered through laboratory testing that half as much SMAD3 protein results in faster maturation than the norm, and an inability to create SMAD3 results in abnormal responses to testosterone.

"SMAD3 is a protein that translates signals from the environment outside the cell to the nucleus, where it switches genes on or off," Dr Itman said. "We have been investigating how SMAD3 influences the growth of testis cells and their ability to respond to testosterone."

Puberty begins when the body starts to produce large amounts of the hormone testosterone. Early, or precocious, puberty involves the onset of puberty before eight years of age and affects around 1 in 10,000 boys. On the other hand, puberty is delayed when testis cells cannot respond normally to testosterone. Altered timing of puberty has implications in adulthood, with precocious puberty linked to reduced adult height and delayed puberty associated with reduced bone density.

Testosterone acts through specialized cells in the testis called Sertoli cells. Before puberty, Sertoli cells multiply, allowing the testis to grow. At puberty, Sertoli cells must stop growing so they can support sperm precursor cells to develop into sperm.

Professor Loveland, Dr Itman and their colleagues have been investigating how Sertoli cells switch from a multiplying state, making the testis big enough to make sperm, to a mature state that sustains sperm production.

"We have discovered that this is not an "on-off" switch. Rather, it is the amount of the SMAD3 protein in the Sertoli cell that is different in the immature, multiplying Sertoli cell compared to the mature, adult cell."

The research identified that it is the amount of SMAD3 present that controls Sertoli cell activity prior to, or after, puberty. When SMAD3 levels are reduced, sperm develop earlier. When SMAD3 is absent, Sertoli cells take longer to respond to testosterone.

Previous research on puberty suggests that pubertal development is delayed in boys exposed to endocrine disrupting compounds, chemicals which impair cell responses to hormones. These chemicals are widely used in industry and in the manufacture of everyday items, such as plastics, cosmetics, paints and detergents.

Dr Itman is supported by a National Health and Medical Research Council (NHMRC) Early Career Project Grant to investigate how these hormone-disrupting chemicals in the environment affect the growth and maturation of Sertoli cells around puberty, including changes to SMAD3 levels and activity.

"We hope that through our research, we will inform decisions about the influence of chemicals in our environment on the timing of puberty in boys and on the fertility of adult men" Dr Itman said.


Story Source:

The above story is based on materials provided by Monash University. Note: Materials may be edited for content and length.


Journal Reference:

  1. C. Itman, C. Wong, B. Hunyadi, M. Ernst, D. A. Jans, K. L. Loveland. Smad3 Dosage Determines Androgen Responsiveness and Sets the Pace of Postnatal Testis Development. Endocrinology, 2011; DOI: 10.1210/en.2010-1453

Cite This Page:

Monash University. "New understanding of male puberty." ScienceDaily. ScienceDaily, 15 March 2011. <www.sciencedaily.com/releases/2011/03/110314100827.htm>.
Monash University. (2011, March 15). New understanding of male puberty. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2011/03/110314100827.htm
Monash University. "New understanding of male puberty." ScienceDaily. www.sciencedaily.com/releases/2011/03/110314100827.htm (accessed April 24, 2014).

Share This



More Health & Medicine News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Pharma Braces for M&A Wave

Big Pharma Braces for M&A Wave

Reuters - Business Video Online (Apr. 22, 2014) Big pharma on the move as Novartis boss, Joe Jimenez, tells Reuters about plans to transform his company via an asset exchange with GSK, and Astra Zeneca shares surge on speculation that Pfizer is looking for a takeover. Joanna Partridge reports. Video provided by Reuters
Powered by NewsLook.com
Study Says Most Crime Not Linked To Mental Illness

Study Says Most Crime Not Linked To Mental Illness

Newsy (Apr. 22, 2014) A new study finds most crimes committed by people with mental illness are not caused by symptoms of their illness or disorder. Video provided by Newsy
Powered by NewsLook.com
Hagel Gets Preview of New High-Tech Projects

Hagel Gets Preview of New High-Tech Projects

AP (Apr. 22, 2014) Defense Secretary Chuck Hagel is given hands-on demonstrations Tuesday of some of the newest research from DARPA _ the military's Defense Advanced Research Projects Agency program. (April 22) Video provided by AP
Powered by NewsLook.com
How Smaller Plates And Cutlery Could Make You Feel Fuller

How Smaller Plates And Cutlery Could Make You Feel Fuller

Newsy (Apr. 22, 2014) NBC's "Today" conducted an experiment to see if changing the size of plates and utensils affects the amount individuals eat. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins