Depression continues to be a major mental health disorder affecting a wide range of individuals worldwide. According to the World Health Organization (WHO), depression affects over three hundred individuals worldwide and it is the leading cause of suicide globally. It is not surprising that most of the researches related to mental health are focused on finding new treatments for depression.
Recently, a new protein was linked to the development of depression and depressive symptoms. Large numbers of studies are being conducted daily to find possible ways of treating depression. The observation that individuals living with depression usually have low levels of serotonin in their central nervous system led to several researches being expanded towards finding certain chemical agents with the potential to inhibit the reuptake of serotonin. This led to the evolution of the serotonin reuptake inhibitors. Following this, scientists were also able to discover the role of norepinephrine, an endogenous neurotransmitter, in depression. This also led to the discovery of norepinephrine reuptake inhibitors. There are several classes of antidepressant drugs. There are also the tricyclic antidepressants just to mention a few. While these drugs have been shown to be effective but their side effects are usually intolerable. Furthermore, they are prone to enormous drug-drug interaction issues. Limited efficacy of these medicines, potential for underdosage/overdosage are the major disadvantages of most antidepressants. Hence the need to find effective drugs for the treatment of depression.
Scientists at Hiroshima University recently conducted an experiment using animal model (mice) to determine the role of the RGS8 gene in the development of depressive behaviour. Variables such as mobility/immobility behaviors were used to determine if the mice showed depressive symptoms or not. The RGS8 protein is encoded by the RGS8 protein in the body. This protein controls a hormone receptor called MCHR1, which helps regulate sleep, feeding and mood. They discovered that mice who had more RGS8 proteins within their body system (more precisely, nervous system) displayed shorter immobility times than those with the normal levels of RGS8. To validate the results of their study, these animals were given antidepressants, the immobility times became shorter. However, when the mice were administered drugs that prevented the MCHR1 from working, the immobility time remained unchanged.
Hence, this study has demonstrated a new possible cause of depression. The scientists also made attempts to look into the brain of mice with the aid of the microscope. The aim was to discover the link between MCHR1 and RGS8 by examining the size of cilia (Cilia are essentially short hair-like projections from certain cells) certain regions of the hippocampus called CA1 where RGS8 levels were the highest. They discovered that mice that were administered with the drug that stopped MCHR1 from working had longer cilia. The role of cilia in diseases has been extensive studied for many years. Individuals with kidney disease, retina disease and obesity has long been demonstrated to have dysfunctional cilia.
It is hoped that these groundbreaking findings and advances in technology and further investigations into this topic will definitely generate valuable insights for future researches that aim to find novel drugs for the treatment of depression.