Epigenetic Alterations in Infants Through C-Sections

Cesarean Delivery just might be causing epigenetic alterations in the DNA of infants at birth. Studies have found this out recently, but it hasn’t been concluded that this change is long lasting. Although, the epigenetic change in these infants born through a c-section may explain and give reasons to why infants delivered in this way have relatively worse incomes than those born naturally. 

“In this study, our focus has been whether the way a baby is born can have an impact on a cellular level in the form of epigenetic alterations in DNA,” Ekstrom said.

Professor Tomas Ekstrom has provided a step towards an explanation with a paper in the American Journal of Obstetrics and Gynecology.

Professor Ekstrom discovered higher rates of methylation in stem cells of a total of 18 babies through c-section and 25 through natural birth. The methylation of our DNA controls and affects which genes will be expressed and which won’t be. Cesarean delivery is one environmental factor that can affect the expression of genes in our DNA and what epigenetic changes will take place. 

“During a vaginal delivery, the fetus is exposed to an increased level of stress, which in a positive way will prepare the unborn baby for life outside the uterus,” said co-author Professor Mikael Norman. “This activation of the fetus’ defense systems doesn’t occur when a cesarean section is performed before labor begins, which in turn could be a possible cause for the noticed differences between the groups.”

“The biological mechanisms predisposing a fetus or a newborn infant to get a certain disease later in life are complex and depend on both genetic and environmental factors during formative years”, Ekstrom added.

Ekstrom showed that epigenetic alterations can be temporary for the infants or permanent, but it is too early for him to see if these identified effects will last. However, it is alarming that some epigenetic changes are not only permanent in the DNA of the newborn, but these changes can also be passed down to offspring after offspring, continually being passed along causing these effects of that one birth to be muligenerational.

 

This Week In Science: Psychedelic Drugs and Tibetans

A couple of this week’s discoveries talked about:

Psychedelic Drugs:

Magic mushrooms alter the brain, and we recently found out how. In a study, a group was given psilocybin. Psilocybin is the chemical found in these magic mushrooms that gives an individual that digested them a psychedelic experience. Another controlled group wasn’t given psilocybin. In the ones with the chemical, they found that the region in the brain dealing with dreams and emotions was amplified, on high. While the region in the brain dealing with ego that gives someone a sense of “self” was decreased and not as active as the others. This affect shows why psychedelics have been considered to be useful in some kinds of psychotherapy.

Understanding how the brain deals with the enhanced cognitive fluency from the psychedelics such as magic mushrooms and LSD may give insights into how they are psychologically useful. Patients may get to experience an “emotional release in psychotherapy”, and also an increase and enhanced way of creative thinking.

Tibetans:

“Tibet has the highest average elevation of any other region in the world, at 4900m above sea level.” For 21,000 years, there have been modern humans in Tibet. These humans have ancestors that were the current inhabitants that moved in around 3000 BCE. A recent study led by Rasmus Nielsen of UC Berkeley suggests that Tibetans’ ability to breathe at such high elevations may be credited to genes passed down to them through their ancestors. This could’ve been accomplished through interbreeding with their extinct cousins known as the Denisovans.

The gene associated with oxygen, EPAS1, is a possibility of this ability. It was found in the bone marrow of a Denisovan. This gene increases hemoglobin and the red blood cell count slightly, getting rid of the negative cardiovascular effects. In most high elevations, people can deal with it through thickening of their blood, but can stress the cardiovascular system. For Tibetans, the ability is permanent and not as unhealthy thanks to EPAS1. 87% of Tibetans have been tested and found with this gene.

“There might be many other species from which we also got DNA, but we don’t know because we don’t have the genomes,” Nielsen said. “The only reason we can say that this bit of DNA is Denisovan is because of this lucky accident of sequencing DNA from a little bone found in a cave in Siberia. We found the Denisovan species at the DNA level, but how many other species are out there that we haven’t sequenced?”

Developed RNA and cGMP: Cardiovascular Disease

Recently developed RNA, named “endless” RNA, by German scientists, can now bind itself to cGMP. Cyclic guanosine monophosphate (cGMP) is what cells are dependent on for transmission of signals and is also what can be responsible for cardiovascular diseases. 

With cardiovascular disease, the signaling pathway in cGMP can malfunction. With this recently developed RNA binding to cGMP, scientists can experiment and find more understandings of lowering the concentration of cGMP in cells. There have been other cases of stimulating cGMP through nitrogen monoxide (NO), but the goal of lowering the levels have not been reached so far.

So what have scientists from the Universities of Stuttgart and Tübingen came up with?

They now use a method where they can “trap” cGMP in certain cells by genetically modifying cells to produce the RNA they developed to bind to cGMP, the second messenger.

RNA is used all over nature to regulate vital functions and gene expressions, Controlling the concentration isn’t an easy task through these RNA sequences. This triplex-based folding motif being able to be inserted into mammalian cells and bind to the second messenger talked about in this post is a first step.

It has been inserted into smooth muscle cells of young mice, and it has shown a significant decreased, controlled level of cGMP. With the ability to control these levels that can be a reason behind cardiovascular diseases, can be an excellent lead into the lives of humans and this disease.