An Ode to COFFEE!

    Caffeine is na organic compound that is produced by different plants, the most known is the coffee bean (Coffea arabica). It is one of the most appreciated (and my favorite) hot beverages to start the day. Its structure é very close to a human compound known as adenosine, a nucleoside produced by the decomposition of methionine, threonina, valine and isoleucine. 

    In addition to being one of the most important parts that make up the DNA strand (it’s the “A” in the ACGT tetrad), it is produced during the metabolism (as saidm by degradation of some aminoacids) and acts as a inhibitor of the motor activity, neuron synapse, respiratory frequency and induces drowsiness.  In some way, one may say it acts such as chemical hourglass, it tells our body how much work we have done. 

 OK, great! But What coffee has to do with this adenosine??? 

    As was pointed out, the chemical structure of caffeine is similar to adenosine’s structure and thus, they can bind to the same cellular receptors!

Picture source: Wikipedia

WELL.... But adenosine makes us sleepy and coffee is my wake up hot drink! 

     Yeah! That is the most interesting thing about cellular receptors! Adenosine binds to these receptors and activates them in order to do its job, however, caffeine, due to its similar structure is capable of binding, but, because its structure is a bit different, it is unable to activate the receptors and blocks it for adenosine binding!        

    So, the receptors are unable to “see” any adenosine” and because of that, the body doesn’t know how much adenosine is there! As a bonus, another neurotransmitter, dopamine, has its activity enhanced and we feel a boost of energy! So caffeine is not a stimulant by itself, it is more like an inhibitor of sleepiness.

  Can I get addicted???  

Well, that is a little debatable. The simple question is yes and no!   

What?

Well, the way receptors usually work is, if they get too activated, the cells tend to reduce the amount of them and if they get less activated, the cells tned to produce more. In the case of caffeine, because it block the normal adenosine recognition, the cell thends to see as if there is not enough receptors and starts to make more.   So, in time, you have more adenosine receptors and the body gets more efficient to detect it and you’ll need more coffee to get the same boost. That is why, after drinking for a while, you feel like it makes no difference. The good news is that this tolerance is not permanent, if you quit coffee for a while, you’ll get to the baseline again!  

But is it healthy?  

Well, although it is a very good question, I still need my coffee to answer it!