Tokyo, April 2 (IANS) Japanese researchers have successfully grown complex skin tissue – complete with hair follicles and oil-producing sebaceous glands – in the laboratory, thereby opening a path to creating functional skin transplants for burn and other patients who require new skin.
The scientists were then able to implant these three-dimensional tissues into living mice, and the tissues formed proper connections with other organ systems such as nerves and muscle fibres.
“Up until now, artificial skin development has been hampered by the fact that the skin lacked the important organs, such as hair follicles and exocrine glands, which allow the skin to play its important role in regulation,” said lead researchers Takashi Tsuji from RIKEN Centre for Developmental Biology in Kobe.
To perform the work, published in Science Advances, the researchers took cells from mouse gums and used chemicals to transform them into stem cell-like induced pluripotent stem cells (iPS) cells.
The researchers were able to make these cells to form the different layers and structures of deeply layered skin.
One important key to the development was that treatment with Wnt10b, a signaling molecule, resulted in a larger number of hair follicles, making the bioengineered tissue closer to natural tissue.
“With this new technique, we have successfully grown skin that replicates the function of normal tissue,” Tsuji noted.
“We are coming ever closer to the dream of being able to recreate actual organs in the lab for transplantation, and also believe that tissue grown through this method could be used as an alternative to animal testing of chemicals,” Tsuji said.
Sunscreen may act as a male contraceptive!
London, April 2 (IANS) Do you lather yourself with sunscreen to keep out that tanning? Beware!
According to a new study, sunscreens are likely to impair sperm cell function, acting as a male contraceptive and lower a man’s chances of parenthood.
The findings of the study showed that many ultra-violet (UV) filtering chemicals commonly used in sunscreens interfere with the function of human sperm cells, and some mimic the effect of the female hormone progesterone.
Sunscreen impairs sperm function by seeping through the skin and into the rest of the body, the researchers explained.
UV-filtering chemicals were found in almost all urine samples and some blood samples.
“These results are of concern and might explain in part why unexplained infertility is so prevalent,” said one of the researchers Niels Skakkebaek, professor at the University of Copenhagen in Denmark.
To examine how UV-filtering chemicals affect healthy sperm, the team tested 29 of the 31 UV filters allowed in sunscreens on healthy human sperm cells, in a buffer solution that resembled the conditions in female fallopian tubes.
The team concentrated on calcium signalling – particularly the sperm-specific calcium ion channel called CatSper, which binds to the female hormone progesterone to control sperm cell fertilisation functions like sperm motility.
The results revealed that 45 percent, of the 29 UV filters tested in the study interfered with the normal functioning of the sperm cell.
Also, 13 UV filters triggered a surge in the movement of calcium ions within sperm cells during binding with progesterone.
“This effect began at very low doses of the chemicals, below the levels of some UV filters found in people after whole-body application of sunscreens,” Skakkebaek said.
The study suggests that regulatory agencies should have a closer look at the effects of UV filters on fertility before approval, the researchers concluded.
Results of the study were presented at the ongoing Endocrine Society’s 98th annual meeting in Boston, US.
Pot belly ups heart failure risk
London, April 2 (IANS) Obesity not only increases the risk of heart failure, but increased belly fat, combined with an ageing population, can also lead to a significant increase in the risk of heart failure, a study says.
The study showed a clear correlation between higher Body Mass Index (BMI), waist circumference and the risk of heart failure.
The researchers saw that with every 10 cm increase in waist circumference was linked to a 29 percent higher risk of heart failure from the analyses of 360,000 participants.
“Overweight individuals had a 35 percent increased risk of heart failure as compared with normal weight individuals and our findings indicate that overweight should be considered a clear risk factor for heart failure,” said first author Dagfinn Aune from Norwegian University of Science and Technology in Norway.
Research showed that a BMI between 25 and 30 kg/m2, which is considered overweight, is also associated with increased risk.
A higher waist-to-hip ratio was also correlated with a progressively greater risk of developing heart failure.
The studies looked at the link between body mass index and the risk of death from heart failure and suggested a 26 percent higher risk for an increase of five BMI units.
“Overweight and obesity increase the risk for heart muscle disease, which is an established risk factor for heart failure,” said Aune.
The findings hold great significance for clinical guidelines on preventing heart failure and they are also important from a public health perspective.
“Physical activity and a more plant-based diet with lots of fruits and vegetables and whole grains are important to prevent overweight and obesity,” Aune said.
