Scientists grow 5-week-old human brain

Scientists successfully grow human brain in lab

Scientists successfully grow human brain in lab

Growing brain tissue in a dish has been done before, but bold new research announced this week shows that scientists’ ability to create human brains in laboratory settings has come a long way quickly.

Researchers at the Ohio State University in the US claim to have developed the most complete laboratory-grown human brain ever, creating a model with the brain maturity of a 5-week-old foetus. The brain, which is approximately the size of a pencil eraser, contains 99 percent of the genes that would be present in a natural human foetal brain.

“It not only looks like the developing brain, its diverse cell types express nearly all genes like a brain,” Rene Anand, professor of biological chemistry and pharmacology at Ohio State and lead researcher on the brain model, said in a statement.

“We’ve struggled for a long time trying to solve complex brain disease problems that cause tremendous pain and suffering. The power of this brain model bodes very well for human health because it gives us better and more relevant options to test and develop therapeutics other than rodents.”

Anand turned to stem cell engineering four years ago after his specialized field of research – examining the relationship between nicotinic receptors and central nervous system disorders – ran into complications using rodent specimens. Despite having limited funds, Anand and his colleagues succeeded with their proprietary technique, which they are in the process of commercializing.

The brain they have developed is a virtually complete recreation of a human foetal brain, primarily missing only a vascular system – in other words, all the blood vessels. But everything else (spinal cord, major brain regions, multiple cell types, signalling circuitry is there). What’s more, it’s functioning, with high-resolution imaging of the brain model showing functioning neurons and brain cells.

The researchers say that it takes 15 weeks to grow a lab-developed brain to the equivalent of a 5-week-old foetal human brain, and the longer the maturation process the more complete the organoid will become.

“If we let it go to 16 or 20 weeks, that might complete it, filling in that 1 percent of missing genes. We don’t know yet,” said Anand.

The scientific benefit of growing human brains in laboratory settings is that it enables high-end research into human diseases that cannot be completed using rodents.

“In central nervous system diseases, this will enable studies of either underlying genetic susceptibility or purely environmental influences, or a combination,” said Anand. “Genomic science infers there are up to 600 genes that give rise to autism, but we are stuck there. Mathematical correlations and statistical methods are insufficient to in themselves identify causation. You need an experimental system – you need a human brain.”

The research was presented this week at the Military Health System Research Symposium.

 

Source:  sciencealert.com

3D printed synthetic biological material

Biological material could be 3D printed to create self-healing shoes:

Biological material could be 3D printed to create self-healing shoes

Biological material could be 3D printed to create self-healing shoes

Shoes as we know them are a pretty modern invention, and a lot of research has gone into creating more comfortable, high-performance materials to cover one’s feet. Even the most advanced rubber-soled shoe can’t compare to the concept being proposed by London designer and researcher Shamees Aden. These shoes would be 3D printed from synthetic biological material for the perfect fit, and they could repair themselves overnight.

The process would start with a 3D scan of the wearer’s foot. This would be used to print the “shoe,” which should conform perfectly to all the curves and lines of the scanned appendage. As for the material that it’s being printed with, that’s what makes the idea so intriguing.

Aden is working with Dr. Martin Hanczyc from the University of Southern Denmark. Dr. Hanczyc works with protocells, one of the most basic biological constructs. A protocell is not quite alive — it’s essentially a lipid membrane containing a collection of organic molecules that may have some biological activity. These structures can self assemble under the right circumstances, so there is great interest in the roll these almost-cells could have played in the appearance of life on Earth, a process known as abiogenesis.

protocell

Printing a foot covering out of protocells would allow for precise control of cushioning and support. The shoes could also react to different situations as they come by puffing up in places for added comfort. At the end of the day, the protocell shoe could be soaked in a solution the help the structures repair themselves.

This is obviously still just a concept — we don’t even have industrial scale biological printing. Even when we do, printing a semi-living shoes probably won’t be high on the to-do list.

Stomach biological clock

Gut clock regulates when we’re hungry:

Gut clock regulates when we're hungry

Gut clock regulates when we’re hungry

Certain nerves in the stomach act as a kind of biological clock, which may help dampen appetite at night and allow heartier eating during the day, researchers have found.

The results, published today in The Journal of Neuroscience, may help shed some light on why shift workers are at high risk of conditions like obesity and diabetes, they say.

Stephen Kentish and colleagues from the University of Adelaide’s Nerve-Gut Research Laboratory studied a particular set of nerves in the muscular layers around the stomachs of laboratory mice.

A major role of these nerves is to help animals know how full they are.

“They send signals back from the stomach to provide feelings of fullness based on the distension of the stomach,” says Kentish.

The researchers wanted to explore how the responses of these nerves varied in the course of a 24-hour period.

To do this, they measured nerve activity when mouse stomach walls were stretched at three-hourly intervals between 6 am and 3 am the following day.

They found that the nerves were least sensitive to the stomach’s stretching at times when the mice were normally awake.

This seems logical, they say, as reduced sensitivity would allow the animals to fill their stomachs at times when they would need more energy.

On the other hand, during times when the mice would normally be sleeping, the nerves in the stomach became much more sensitive. This meant that the brain received a signal of fullness more quickly, shutting down the desire to eat.

“This variation repeats every 24 hours in a circadian manner, with the nerves acting as a clock to coordinate food intake with energy requirements,” Kentish says.

Following on from this work, the researchers also found that these nerve cells expressed a set of “circadian clock” genes that are also expressed in the brain region that regulates the wider circadian rhythm of the body.

In other words, the researchers say, these nerve cells appear to form a kind of neural clock in the stomach, regulating the amount of food needed to elicit fullness during the day and night.