[100 Challenge] DanJi’s reading note_66

The link between life and medicine
The principle of the human body is understood as medicine and the age of bio
Author Kim Sung Hoon
Published Woongjin Knowledge House
Issued on February 28, 2023.

Specific Combinations and Side Effects between Drugs and In vivo Drug Targets
Drugs that enter the body cause the expected drug action by binding to their target, which involves various physiological actions, such as specific enzymes or proteins. However, many proteins in our body have similar structures to each other. Therefore, drugs that enter the body can bind to the original target and other proteins with a structure identical to the target, resulting in unexpected effects.
In addition to the target COX-2, Vioxx, for example, can bind to another enzyme, COX-1, which has a similar structure to COX-2 in the human body but has different physiological functions. Although viox was developed to bind only to COX-2, it is still possible to bind to COX-1 and have side effects. And above all, there may be a variety of functions in COX-2 itself that we have not yet discovered.
The side effects of a drug can be caused by a combination of a target to which each drug acts (side effect-1) and a physiological function involving one or more of the original target (side effect-2) or a combination of these cases. For this reason, scientists developing drugs use all knowledge and technology possible to create drugs so that a specific drug can only bind to a desired target (called a particular combination) and exhibit only the desired efficacy. First, the specificity between a drug and its target is revealed by a good analysis of the structure of the target, and it opens up the possibility of overcoming and improving difficulties revealed during the research process. However, even if a specific combination between a drug and a target is possible, side effects of a drug can be caused by another reason.
It is advisable to be careful when you encounter cases in the market where drugs or health foods with unclear evidence are advertised as panacea or as drugs with no side effects. As long as the genes and proteins that make up our body are intertwined like webs, and our knowledge is still incomplete, premature confidence can be rather poisonous.
It is a frank attitude to say that in our body's complex network, it is almost impossible to accurately select one drug target and select only one of the complex functions performed by that target and control it with as many drugs as you want. However, at the current level of science, it is best to devise and use a drug or strategy that maximizes the desired efficacy as much as possible and minimizes the side effects accompanying it.
Viagra Viagra, an impotence treatment developed by the multinational pharmaceutical company Pfizer, is a monumental invention that has created a new category of lifestyle drugs in the history of drug development. Viagra was initially developed as a treatment for angina, a vascular disease, as a drug that induces vasodilation. However, during clinical trials, it was found to have an excellent effect in improving men's impotence, and it was eventually developed as a treatment for impotence. The principle behind Viagra's support for the erectile male genitals is that sildenafil, the main ingredient, aids in the secretion of a chemical called cyclic GMPCyclic GMP, which is produced when men are sexually excited while at the same time inhibiting the activity of phosphodiesterase type 5 (PDE5), an impotence-inhibiting enzyme. Viagra is a successful case of developing a new drug that is very different from general new drug development. On the other hand, it has been created as one of the best-selling drugs worldwide by actively developing a kind of side effect for new purposes that caused a different action from the intended action.