Genetic Basis of Postpartum Depression

PPD, GABA, and the Thalami

    A recent study from the UNC School of Medicine revealed that 14% of the variability in postpartum depression (PPD) is due to genetic factors/on a genetic basis and also provided a glimpse into the connections PPD has with a variety of pre-existing psychiatric disorders. The basis of PPD symptoms lays with GABAergic neurons in the hypothalamus and thalamus; areas of your brain responsible for regulatory functions (hunger, thirst, thyroid function, etc), and seem to have promising advancements for future PPD research. This data was collected using a genome-wide-association study and compiled data in order to get a bigger glimpse into PPD. Jerry Guintivano, PhD, assistant professor of psychiatry at the UNC School of Medicine, was able to identify similarities in the genetic architecture of PPD and major depression, bipolar disorder, anxiety disorders, post-traumatic stress disorder, insomnia, and polycystic ovary syndrome, meaning "...PPD symptoms likely occur as a result of the interplay between the same genes involved in these other psychiatric and hormone-related conditions." Furthermore, the research concluded a link between PPD, its genetic architectural siblings, and GABAergic neurons in the hypothalamus and thalamus of the brain: neurons releasing GABA neurotransmitters appear to have a link to PPD and its similar familial connections of disorders. Brexanolone is a common drug used to treat PPD and now researchers are able to see the interconnectedness of Brexanolone and the two regions of the brain, which is promising for additional treatment in the foreseeable future. Due to such a wide study and too few PPD cases, however, the researchers at UNC were unable to identify specific locations on the genome or loci that are consistently similar amongst the data group.

    This study was fascinating to read and it provided an overlap between multiple specialties in biology -- from neuroscience to anatomy to physiology. Women's health is making big strides in the 21st century and I think this article is just another step towards more progress being made. The linkage between hormones and psychiatric disorders seems to be a hot topic, and scientists had avoided looking at female models for a long time due to the "complexity" of female hormones and their interactions with physiological processes in the body. But now, we have more evidence that encourage this research and should make women feel a lot better about the improvements being made and the connections established between the two factors. Furthermore, the researchers had also confirmed that PPD is genetic which is also a huge step as well! This can impact treatment plans for pregnant women and might improve their quality of postpartum treatment if they are better prepared and more aware of their chances for PPD. Nevertheless, this study was so interesting to read about and I love the idea of its medical/pharmaceutical improvements as well. 

LINKS:

1) https://neurosciencenews.com/post-partum-depression-genetics-24968/ 

2) https://news.unchealthcare.org/2023/10/researchers-confirm-postpartum-depression-heritability-home-in-on-treatment-mechanism/ 

Schizophrenia symptoms alleviated in model mice

Researchers from Case Western Reserve University, studied a brain cell receptor called ErbB4. This specific receptor is altered in adults who have schizophrenia. The purpose of this brain receptor is to maintain a neurotransmitter, GABA, which prevents brain cells from overreacting as well as keeping fear and anxiety at normal levels. In this specific study the researchers engineered two new mice models of schizophrenia, the first mouse model  was treated with a chemical that switches the "off" gene encoding ErbB4 while in the second mouse model the receptor was missing from the beginning which in turn hampered brain cell development. The researchers found that in restoring the brain receptor in the first mouse model the mice had reduced hyperactivity and normalized fear responses. This information was super useful in the treatment of patients because researchers believe by adding or restoring ErbB4, it could reduce symptoms of schizophrenia in patients.




References:
https://www.webmd.com/schizophrenia/schizophrenia-symptoms
https://www.sciencedaily.com/releases/2018/11/181130120442.htm

I Can See Clearly Now the GABA is Almost Gone! - How Zebrafish Recover From Blindness

A recent study funded by the National Eye Institute found a link between the neurotransmitter GABA, or gamma-aminobutyric acid, and recovery from blindness in zebrafish.  For some time now, scientists were aware of the zebrafish's ability to recover from loss of vision that would normally blind humans permanently.  This is due to the zebrafish having a miraculous ability to regenerate cells in the retina.  Prior studies showed that dying retinal cells produced signals to trigger Muller glia, which revert back to an undifferentiated state and divide.into new cells.  Studies in mice on the brain and pancreas indicated that GABA could play a role in the regeneration process, where low levels signaled stem cells to  divide.  The researchers of the current study, therefore, hypothesized that GABA in zebrafish could be a factor in the regeneration of retinal cells.  To test their theory they injected zebrafish with GABA inhibitors.  They found that these fish responded with retinal cell regeneration.  Fish with retinal damage that were given high levels of GABA, on the other hand, displayed little to no regeneration.  These findings clearly support the hypothesis that GABA plays a very important roll in the regeneration of new cells.

I found this article interesting because I often joke about how I'm going blind because my vision is so poor.  But on a serious note I think the findings in this study could be very significant for finding cures to diseases in humans that affect vision, and it could lead to new treatments to cure blindness.  It is also the first study to report these kind of results, so with more experiments in the future it would be fascinating to see what else researchers find out about the subject.