Cortisol

Today I want to tell you about CAS Registry Number: 50-23-7, also known as cortisol.  I first started thinking about cortisol in 2011, but I didn't follow up on it then.  There seems to be a link between cortisol, stress, metabolism, eating behavior, obesity, circadian rhythms, and wellness (feelings of well being) or lack thereof (depression).

In my research this morning, there were some ties between cortisol and anxiety, which I have written about previously.

This blog was prompted by the recent article in Psychology Today which suggested that waiting 20 minutes when you feel a moment of panic is long enough for your body to excrete cortisol via your urine so you will cease to feel the "fight-or-flight" response.

This post gave me a pause to think about how our own minds create problems that our own minds can solve if we just give ourselves a minute to breathe and let go.  Some great illustrations about self-care can be found here.  Another great set of ideas is in the graphic posted in this blog (below).  There are some other great pictures here, especially the series about "feeling overwhelmed."

The infographic posted above actually has a firm foundation in the scientific literature.  Many studies suggest that people turn to calorie-dense foods (like ice cream) when faced with a stressful life event.  Acutally, I'm giving a talk next month on the science of ice cream, and I have to get cracking on that outreach project.

Being that it's the 100th Anniversary of X-ray Crystallography, I wanted to also show the peptide called "1AX8," also known as leptin.  It seems that lepin has a lot to do with metabolic control.  Leptin is secreted by adipose tissue.  It is part of the mechanism to maintain a particular body weight.  Individuals who are obese are said to be leptin-insensitive.  Leptin produces feelings of satiety (satisfaction after eating) in normal individuals.  Without crystallography, we wouldn't have the understanding of protein, peptide, and small molecule structures to create models for understanding the energetic considerations in ligand-target interactions.  Although aptamer generation is carried out via a combinatorial approach, maybe someday we will be able to approach the creation of biological drugs from a purely structural understanding.

At this point, we can chemically prepare analogues for small molecules like cortisol, but leptin and leptin-mimics are probably classified as biologic medical products, meaning that they must be made by a living organism.  I don't know whether aptamers are classified as biologics or if they are considered purely synthetic ligands.  I'm sure peptoids are not considered biologics since they are non-native structures.

I don't know if we understand the equilibria involved in cortisol and leptin in vivo well enough yet to interfere with the body's natural biorhythms.  Much of the published work is based on the phenotpyes associated with human diseases (Cushing's syndrome is a result of prolonged exposure to high levels of cortisol) or animal models of genetic mutation (a new 'fat gene' has been reported, IRX3).  I have written about genetic factors linked to obesity elsewhere.  I wonder if eventually we will become a race of 'perfect humans' via biologics which target all genetic mistakes.  Probably not since we're ~15 years away from a total collapse of our civilization, according to NASA-funded research that points to our unsustainable resource exploitation and increasingly unequal wealth distribution as factors leading to our demise.

In other news, we've been biking like crazy.  I have also been going to Zumba 2x per week.  I've noticed a pain in my ankle/foot but more muscle tone in my arms and better posture.  We're planning to ride from Ventura to Santa Barbara and back (60 miles) so wish me luck on that adventure.  I think the music and group riding are lowering my cortisol levels and the shedding of body fat is lowering my leptin levels.  I also hope my immune system is thriving, I've been doing more singing (while riding my bike) and feeling more positive.

References: 

Torres, S. J.; Nowson, C. A. "Relationship between stress, eating behavior, and obesity" Nutrition (2007) 23, 887-894.

Herbert, J. "Cortisol and depression: three questions for psychiatry" Psychological Medicine (2013) 43, 449-469.

Parrott, A. C. "Human psychobiology of MDMA or 'Ecstasy': an overview of 25 years of empirical research" Human Psychopharmacology (2013) 28, 289-307.

Chanda M. L.; Levitin, D. J. "The neurochemistry of music" Trends in cognitive sciences (2013), 17, 179-193.

Kandasamy, K; et al. "Cortisol shifts financial risk preferences" Proceedings of the National Academy of Sciences (2014) 111, 3608-3613.

Neff, K. "The Physiology of Self-Compassion" The Power of Self-Compassion via Psychology Today (2012) http://bit.ly/1r6Ygm6

Breuning, L. G. "Awareness of Death Makes Us Human" Your Neurochemical Self via Psychology Today (2014) http://bit.ly/1euVIJ0