Showing posts with label sperm. Show all posts
Showing posts with label sperm. Show all posts
Sunday, 27 April 2014
Trauma of life is passed down in SPERM to future generations
The children of people who have experienced extremely traumatic events are more likely to develop mental health problems. And new research shows this is because experiencing trauma leads to changes in the sperm.
These changes can cause a man’s children to develop bipolar disorder and are so strong they can even influence the man’s grandchildren. Psychologists have long known that traumatic experiences can induce behavioural disorders that are passed down from one generation to the next. However, they are only just beginning to understand how this happens.
Researchers at the University of Zurich and ETH Zurich now think they have come one step closer to understanding how the effects of traumas can be passed down the generations.
The researchers found that short RNA molecules – molecules that perform a wide range of vital roles in the body - are made from DNA by enzymes that read specific sections of the DNA and use them as template to produce corresponding RNAs. Other enzymes then trim these RNAs into mature forms.
Cells naturally contain a large number of different short RNA molecules called microRNAs. They have regulatory functions, such as controlling how many copies of a particular protein are made.
The researchers studied the number and kind of microRNAs expressed by adult mice exposed to traumatic conditions in early life and compared them with non-traumatised mice. They discovered that traumatic stress alters the amount of several microRNAs in the blood, brain and sperm – while some microRNAs were produced in excess, others were lower than in the corresponding tissues or cells of control animals.
These alterations resulted in misregulation of cellular processes normally controlled by these microRNAs. After traumatic experiences, the mice behaved markedly differently - they partly lost their natural aversion to open spaces and bright light and showed symptoms of depression.
These behavioural symptoms were also transferred to the next generation via sperm, even though the offspring were not exposed to any traumatic stress themselves. The metabolisms of the offspring of stressed mice were also impaired - their insulin and blood sugar levels were lower than in the offspring of non-traumatised parents.
‘We were able to demonstrate for the first time that traumatic experiences affect metabolism in the long-term and that these changes are hereditary,’ said Professor Isabelle Mansuy. ‘With the imbalance in microRNAs in sperm, we have discovered a key factor through which trauma can be passed on.’
However, certain questions remain open, such as how the dysregulation in short RNAs comes about. Professor Mansuy said: ‘Most likely, it is part of a chain of events that begins with the body producing too many stress hormones.’ Importantly, acquired traits other than those induced by trauma could also be inherited through similar mechanisms, the researcher suspects.
Article: 23rd April 2014 www.dailymail.co.uk
Saturday, 7 January 2012
Sperm grown in laboratory in fertility breaththrough
Men suffering from fertility problems have been given renewed hope after a team of scientists were able to grow sperm in a laboratory. In a world's first, scientists have successfully grown mouse sperm in a lab dish and are now hoping they would be able to produce human sperm too.
The team of researchers were led by Professor Stefan Schlatt from Germany’s Muenster University and using just a few cells that are responsible for its production, successfully reproduced mice sperm. They are now hoping they will be able to repeat the technique to produce human sperm, which could then be used in fertility treatments to enable infertile men to father their own children.
Commenting on the research, one Isreali team member, Prof. Mahmoud Huleihel, said: “I believe it will eventually be possible to routinely grow human male sperm to order by extracting tissue containing germ cells from a man’s testicle and stimulating sperm production in the laboratory.” To grow the sperm the scientists wanted to ensure they created conditions that were as similar to those found in the testicles as possible.
As a result, the germ cells were surrounded by agar jelly and grown in an environment with a temperature that was just below the normal body temperature of humans. Professors Schlatt and Huleihel along with their teams are now trying to emulate the results in human sperm “as quickly as possible.”
"We have already applied the same tests as we did with mice in the laboratory, using human cells, but as yet have not had success,” Huleihel noted. “We are confident that if it can be done in a mammal such as a mouse it can be done in humans.”
He added: “We are experimenting with a number of different compounds to get the germ cells to grow into sperm. And we believe it will be possible. And, hopefully, soon.” The work carried out by the research group has received high praise from a number of fertility experts.
One of the UK’s leading fertility scientists, Professor Richard Sharpe, who is based at Edinburgh University, is hoping to get involved with the project in the near future. He said: “This is a significant step forward towards making human sperm.”
Meanwhile, one of the NHS’ top consultants in infertility, Stephen Gordon, added: “This is an amazing development that could revolutionise fertility treatment and allow every man to be a natural father. “Infertile men naturally want to be the father of their child but at present have to accept that can't happen,” he said. “With the mouse discovery, that could now be a possibility.”
The results of the research project have been published in a major scientific journal by Nature. Article: 3rd January 2012 www.healthcareglobal.com
Read more about fertility and sperm donation at www.prideangel.com
The team of researchers were led by Professor Stefan Schlatt from Germany’s Muenster University and using just a few cells that are responsible for its production, successfully reproduced mice sperm. They are now hoping they will be able to repeat the technique to produce human sperm, which could then be used in fertility treatments to enable infertile men to father their own children.
Commenting on the research, one Isreali team member, Prof. Mahmoud Huleihel, said: “I believe it will eventually be possible to routinely grow human male sperm to order by extracting tissue containing germ cells from a man’s testicle and stimulating sperm production in the laboratory.” To grow the sperm the scientists wanted to ensure they created conditions that were as similar to those found in the testicles as possible.
As a result, the germ cells were surrounded by agar jelly and grown in an environment with a temperature that was just below the normal body temperature of humans. Professors Schlatt and Huleihel along with their teams are now trying to emulate the results in human sperm “as quickly as possible.”
"We have already applied the same tests as we did with mice in the laboratory, using human cells, but as yet have not had success,” Huleihel noted. “We are confident that if it can be done in a mammal such as a mouse it can be done in humans.”
He added: “We are experimenting with a number of different compounds to get the germ cells to grow into sperm. And we believe it will be possible. And, hopefully, soon.” The work carried out by the research group has received high praise from a number of fertility experts.
One of the UK’s leading fertility scientists, Professor Richard Sharpe, who is based at Edinburgh University, is hoping to get involved with the project in the near future. He said: “This is a significant step forward towards making human sperm.”
Meanwhile, one of the NHS’ top consultants in infertility, Stephen Gordon, added: “This is an amazing development that could revolutionise fertility treatment and allow every man to be a natural father. “Infertile men naturally want to be the father of their child but at present have to accept that can't happen,” he said. “With the mouse discovery, that could now be a possibility.”
The results of the research project have been published in a major scientific journal by Nature. Article: 3rd January 2012 www.healthcareglobal.com
Read more about fertility and sperm donation at www.prideangel.com
Sunday, 7 August 2011
Sperm produced from stem cells may help rid male infertility
Researchers may be able to produce sperm from stem cells in the battle against infertility.
If you know just one thing about embryonic stem cells, it’s probably that they have the potential to grow into any type of cell in the body. That, of course, is why scientists find them so valuable.
But having the potential to become any type of cell is not the end game -- research groups around the world are trying to figure out the precise recipe for turning those stem cells into specific types of cells that would be useful for studying or treating various diseases.
This week, a group of Japanese researchers from Kyoto University said they had figured out a way to turn embryonic stem cells into the more specific type of stem cell that makes sperm. Their findings were published online Thursday in the journal Cell.
How did they know they got it right? They took those sperm progenitor cells and injected them into the testes of infertile mice. Those mice went on to father healthy mouse pups that were able to reproduce themselves.
These experiments offer hope to men who struggle with infertility issues. But there’s a long way to go before this work can be translated into people.
For starters, the recipe used to transform the mouse stem cells into sperm will need to be modified to work with human embryonic stem cells. But infertile men who want to pass their own DNA to their children won’t be helped much by this, at least not directly. By the time a person is of reproductive age -- let alone gets past the first several days of embryonic development -- it’s too late to make embryonic stem cells with one’s matching DNA.
So the second step will be to figure out a way to make the sperm precursor cells out of induced pluripotent stem cells, or iPS cells. These are the cells taken from skin or another adult tissue and rewound to an early state where they are flexible enough to -- say it with me -- become any type of cell in the body.
The Japanese researchers were able to make sperm progenitor cells out of iPS cells, and some mouse pups were born as a result, but the entire process worked less well than with embryonic stem cells. If these technical hurdles can be overcome, a man with fertility issues theoretically could donate a patch of skin and let scientists use that to produce sperm that contains his DNA.
If you know just one thing about embryonic stem cells, it’s probably that they have the potential to grow into any type of cell in the body. That, of course, is why scientists find them so valuable.
But having the potential to become any type of cell is not the end game -- research groups around the world are trying to figure out the precise recipe for turning those stem cells into specific types of cells that would be useful for studying or treating various diseases.
This week, a group of Japanese researchers from Kyoto University said they had figured out a way to turn embryonic stem cells into the more specific type of stem cell that makes sperm. Their findings were published online Thursday in the journal Cell.
How did they know they got it right? They took those sperm progenitor cells and injected them into the testes of infertile mice. Those mice went on to father healthy mouse pups that were able to reproduce themselves.
These experiments offer hope to men who struggle with infertility issues. But there’s a long way to go before this work can be translated into people.
For starters, the recipe used to transform the mouse stem cells into sperm will need to be modified to work with human embryonic stem cells. But infertile men who want to pass their own DNA to their children won’t be helped much by this, at least not directly. By the time a person is of reproductive age -- let alone gets past the first several days of embryonic development -- it’s too late to make embryonic stem cells with one’s matching DNA.
So the second step will be to figure out a way to make the sperm precursor cells out of induced pluripotent stem cells, or iPS cells. These are the cells taken from skin or another adult tissue and rewound to an early state where they are flexible enough to -- say it with me -- become any type of cell in the body.
The Japanese researchers were able to make sperm progenitor cells out of iPS cells, and some mouse pups were born as a result, but the entire process worked less well than with embryonic stem cells. If these technical hurdles can be overcome, a man with fertility issues theoretically could donate a patch of skin and let scientists use that to produce sperm that contains his DNA.
Monday, 29 November 2010
Low sperm counts making it harder for couples to conceive
Low sperm counts and reduced male fertility may be making it even harder for couples to conceive and be contributing to low birth rates in many countries, reveals a new European Science Foundation (ESF) report launching at a meeting in Paris.
More than 10% of couples worldwide are infertile, contributing to the growing demand for assisted reproduction techniques such as in vitro fertilisation (IVF) for which Robert G. Edwards won the Nobel Prize in Medicine last month.
Sperm counts have dropped significantly in the last 50 years in developed countries. Today, at least one in five 18-25 year old men in Europe have semen quality in subfertile range. Testosterone levels are also declining. This is mirrored by increasing testicular cancer in most industrialised countries and more developmental abnormalities such as undescended testes. All of these factors are linked to reduced fertility and may have common origins during foetal development.
“The important impact of men’s reproductive health on a couple’s fertility is often overlooked,” said Professor Niels Skakkebæk from the University of Copenhagen, who co-authored the report. “Women postponing motherhood have reduced fertility, and we now see that poor sperm may be making it even harder to conceive. While poor sperm may be part of the reason more couples are using IVF it may also be making those therapies less successful.”
Skakkebæk continues: “We need a common strategy in Europe to target research so we can address the poor state of men’s reproductive health. That this decrease in male reproductive health has occurred in just a few decades suggests it’s caused by environmental and lifestyle factors rather than genetics. So it is preventable if we correctly identify the causes.”
In men some lifestyle factors such as obesity and smoking can affect sperm counts, but the effects are small. In contrast, if women smoke heavily in pregnancy, a much larger fall in sperm count is likely in their sons when they grow up. Testosterone levels naturally drop as men age, which may predispose men to cardiovascular and metabolic health problems that pose large financial and healthcare issues for national governments. Low sperm counts and low testosterone levels are both associated with increased risk of early death for men.
To read more go to http://bit.ly/dUnZKH
More than 10% of couples worldwide are infertile, contributing to the growing demand for assisted reproduction techniques such as in vitro fertilisation (IVF) for which Robert G. Edwards won the Nobel Prize in Medicine last month.
Sperm counts have dropped significantly in the last 50 years in developed countries. Today, at least one in five 18-25 year old men in Europe have semen quality in subfertile range. Testosterone levels are also declining. This is mirrored by increasing testicular cancer in most industrialised countries and more developmental abnormalities such as undescended testes. All of these factors are linked to reduced fertility and may have common origins during foetal development.
“The important impact of men’s reproductive health on a couple’s fertility is often overlooked,” said Professor Niels Skakkebæk from the University of Copenhagen, who co-authored the report. “Women postponing motherhood have reduced fertility, and we now see that poor sperm may be making it even harder to conceive. While poor sperm may be part of the reason more couples are using IVF it may also be making those therapies less successful.”
Skakkebæk continues: “We need a common strategy in Europe to target research so we can address the poor state of men’s reproductive health. That this decrease in male reproductive health has occurred in just a few decades suggests it’s caused by environmental and lifestyle factors rather than genetics. So it is preventable if we correctly identify the causes.”
In men some lifestyle factors such as obesity and smoking can affect sperm counts, but the effects are small. In contrast, if women smoke heavily in pregnancy, a much larger fall in sperm count is likely in their sons when they grow up. Testosterone levels naturally drop as men age, which may predispose men to cardiovascular and metabolic health problems that pose large financial and healthcare issues for national governments. Low sperm counts and low testosterone levels are both associated with increased risk of early death for men.
To read more go to http://bit.ly/dUnZKH
Tuesday, 9 November 2010
Men who use laptop computers on their knees may harm their 'sperm'
Millions of men are putting their reproductive health at risk by balancing their laptops on their knees, experts have warned.
Researchers from the State University of New York asked 29 young men to work on computers placed on their laps. They then measured the change in temperature in their genital area. Study leader, Professor Yelim Sheynkin, said: 'Millions and millions of men are using laptops now, especially those in the reproductive age range.
'Within 10 or 15 minutes their scrotal temperature is already above what we consider safe, but they don't feel it.' Around one in seven couples in the UK have trouble conceiving and male infertility plays a part in around half of these cases.
Under normal circumstances, the position of the testicles outside the body keeps them a few degrees cooler than the inside of the body, which is necessary for sperm production.
No studies have yet researched how laptops affect male fertility, but earlier research has showed that warming the scrotum even more than one degree Celsius is enough to damage sperm.
The latest study, published in the journal Fertility and Sterility, found the mens' testicle temperature had risen by up to 2.5 C after holding a laptop on their knees for an hour.
Professor Sheynkin said: 'I wouldn't say that if someone starts to use laptops they will become infertile.' However, he warned that frequent use might contribute to reproductive problems because 'the scrotum doesn't have time to cool down.'
The team found when the men sat with their legs spread wide with a large lap pad under the computer they could keep their testicles cooler. But it still took less than 30 minutes before they began overheating.
'No matter what you do, even with the legs spread wide apart, the temperature is still going to be higher than what we call safe,' Professor Sheynkin said.
To read more go to http://bit.ly/a6G765
Researchers from the State University of New York asked 29 young men to work on computers placed on their laps. They then measured the change in temperature in their genital area. Study leader, Professor Yelim Sheynkin, said: 'Millions and millions of men are using laptops now, especially those in the reproductive age range.
'Within 10 or 15 minutes their scrotal temperature is already above what we consider safe, but they don't feel it.' Around one in seven couples in the UK have trouble conceiving and male infertility plays a part in around half of these cases.
Under normal circumstances, the position of the testicles outside the body keeps them a few degrees cooler than the inside of the body, which is necessary for sperm production.
No studies have yet researched how laptops affect male fertility, but earlier research has showed that warming the scrotum even more than one degree Celsius is enough to damage sperm.
The latest study, published in the journal Fertility and Sterility, found the mens' testicle temperature had risen by up to 2.5 C after holding a laptop on their knees for an hour.
Professor Sheynkin said: 'I wouldn't say that if someone starts to use laptops they will become infertile.' However, he warned that frequent use might contribute to reproductive problems because 'the scrotum doesn't have time to cool down.'
The team found when the men sat with their legs spread wide with a large lap pad under the computer they could keep their testicles cooler. But it still took less than 30 minutes before they began overheating.
'No matter what you do, even with the legs spread wide apart, the temperature is still going to be higher than what we call safe,' Professor Sheynkin said.
To read more go to http://bit.ly/a6G765
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