Monthly Archives: July 2015

Scientists have developed an eye drop that can dissolve cataracts

Researchers in the US have developed a new drug that can be delivered directly into the eye via an eye dropper to shrink down and dissolve cataracts – the leading cause of blindness in humans.

While the effects have yet to be tested on humans, the team from the University of California, San Diego hopes to replicate the findings in clinical trials and offer an alternative to the only treatment that’s currently available to cataract patients – painful and often prohibitively expensive surgery.

Researchers in the US have developed a new drug that can be delivered directly into the eye via an eye dropper to shrink down and dissolve cataracts – the leading cause of blindness in humans.

While the effects have yet to be tested on humans, the team from the University of California, San Diego hopes to replicate the findings in clinical trials and offer an alternative to the only treatment that’s currently available to cataract patients – painful and often prohibitively expensive surgery.

Affecting tens of millions of people worldwide, cataracts cause the lens of the eye to become progressively cloudy, and when left untreated, can lead to total blindness. This occurs when the structure of the crystallin proteins that make up the lens in our eyes deteriorates, causing the damaged or disorganised proteins to clump and form a milky blue or brown layer. While cataracts cannot spread from one eye to the other, they can occur independently in both eyes.

Scientists aren’t entirely sure what cases cataracts, but most cases are related to age, with the US National Eye Institute reporting that by the age of 80, more than half of all Americans either have a cataract, or have had cataract surgery. While unpleasant, the surgical procedure to remove a cataract is very simple and safe, but many communities in developing countries and regional areas do not have access to the money or facilities to perform it, which means blindness is inevitable for the vast majority of patients.

According to the Fred Hollows Foundation, an estimated 32.4 million people around the world today are blind, and 90 percent of them live in developing countries. More than half of these cases were caused by cataracts, which means having an eye drop as an alternative to surgery would make an incredible difference.

The new drug is based on a naturally-occurring steroid called lanosterol. The idea to test the effectiveness of lanosterol on cataracts came to the researchers when they became aware of two children in China who had inherited a congenital form of cataract, which had never affected their parents. The researchers discovered that these siblings shared a mutation that stopped the production of lanosterol, which their parents lacked.

So if the parents were producing lanosterol and didn’t get cataracts, but their children weren’t producing lanosterol and did get cataracts, the researchers proposed that the steroid might halt the defective crystallin proteins from clumping together and forming cataracts in the non-congenital form of the disease.

They tested their lanosterol-based eye drops in three types of experiments. They worked with human lens in the lab and saw a decrease in cataract size. They then tested the effects on rabbits, and according to Hanae Armitage at Science Mag, after six days, all but two of their 13 patients had gone from having severe cataracts to mild cataracts or no cataracts at all. Finally, they tested the eye drops on dogs with naturally occurring cataracts. Just like the human lens in the lab and the rabbits, the dogs responded positively to the drug, with severe cataracts shrinking away to nothing, or almost nothing.

The results have been published in Nature.

“This is a really comprehensive and compelling paper – the strongest I’ve seen of its kind in a decade,” molecular biologist Jonathan King from the Massachusetts Institute of Technology (MIT) told Armitage. While not affiliated with this study, King has been involved in cataract research for the past 15 years. “They discovered the phenomena and then followed with all of the experiments that you should do – that’s as biologically relevant as you can get.”

The next step is for the researchers to figure out exactly how the lanosterol-based eye drops are eliciting this response from the cataract proteins, and to progress their research to human trials.

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One night of sleep loss can alter clock genes in your tissues

Reading a biological clock in the dark

Swedish researchers at Uppsala University and the Karolinska Institute have found that genes that control the biological clocks in cells throughout the body are altered after losing a single night of sleep, in a study that is to be published in the Journal of Clinical Endocrinology and Metabolism.

“Previous research has shown that our metabolism is negatively affected by sleep loss, and sleep loss has been linked to an increased risk of obesity and . Since ablation of in animals can cause these disease states, our current results indicate that changes of our clock genes may be linked to such negative effects caused by sleep loss”, says Jonathan Cedernaes, lead author on the study and a researcher at Uppsala University.

For the study the researchers studied 15 healthy normal-weight men who on two separate occasions came to the lab for almost 2-night long stays. During the second night the participants slept as usual (over 8 hours) in one of the two sessions, while they were kept awake in the other of these sessions, but in random order. To minimize the influence of various environmental factors, light conditions, food intake and activity levels in the lab were strictly controlled and the participants were bed-restricted when they were kept awake.

Following the second night on both occasions that the men were studied, small were taken from the superficial fat on the stomach, and from the muscle on the thigh – two kinds of tissues that are important for regulating metabolism and controlling . Blood samples were also taken before and after the participants had consumed a sugar solution to test their insulin sensitivity, a practice commonly done to exclude the presence of diabetes or a metabolic state called impaired , which can precede type-2 diabetes.

Molecular analyses of the collected tissue samples showed that the regulation and activity of clock genes was altered after one night of sleep loss. The activity of genes is regulated by a mechanism called epigenetics. This involves chemical alterations to the DNA molecule such as methyl groups – a process called methylation – which regulates how the genes are switched on or off. The researchers found that clock genes had increased numbers of such DNA marks after sleep loss. They also found that the expression of the genes, which is indicative of how much of the genes’ product is made, was altered.

“As far as we know, we are the first to directly show that epigenetic changes can occur after sleep loss in humans, but also in these important tissues”, says Dr. Cedernaes. “It was interesting that the methylation of these genes could be altered so quickly, and that it could occur for these metabolically important clock genes”, he continues.

The changes that the researchers observed were however different in the adipose tissue and the skeletal muscle. “This could suggest that these important molecular clocks are no longer synchronized between these two tissues”, Dr. Cedernaes says. “As such, ‘clock desynchrony’ between tissues has been linked to metabolic pathologies, this could suggest that these tissue-specific changes were linked to the impaired glucose tolerance that our participants demonstrated after the night that they had been kept awake”

The researchers do not at this stage know how persistent these changes are. “It could be that these changes are reset after one or several nights of good sleep. On the other hand, epigenetic marks are suggested to be able to function a sort of metabolic memory, and have been found to be altered in e.g. shift workers and people suffering from type 2 diabetes”, Dr. Cedernaes points out. “This could mean that at least some types of or extended wakefulness, as in shift work, could lead to changes in the genome of your tissues that can affect your metabolism for longer periods”, Dr. Cedernaes concludes.

Phones With The Highest Radiation

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According to new research from the Weizmann Institute of Science in Israel, certain cellphones may be exposing us to harmful levels of electromagnetic radiation.

Published in the Biochemical Journal, the study found that a single us of a specific cellphones for just 15 minutes can trigger brain cell changes associated with cancerous cell division.