What we put into our bodies can affect how they function and what they do. For example, a sugary snack will probably make you feel differently than a high-protein meal. Similarly, different medicines elicit different responses in your body, and pharmacologists try to fine-tune each medicine to balance the desired (on-target) with the undesired (off-target) effects—a branch of pharmacology called pharmacodynamics.

Most medicines work by binding to a molecular target, usually proteins like receptors or enzymes, and either blocking or supporting its activity, which results in their therapeutic effects.

Have you ever wondered what happens inside your body when you take a medicine? An area of pharmacology called pharmacokinetics is the study of precisely that. Here, we follow a medicine as it enters the body, finds its therapeutic target (also called the active site), and then eventually leaves the body.

To begin, a person takes or is given a dose of medicine by a particular route of administration, such as by mouth (oral); through the skin (topical), mucous membranes
(nasal), or lungs (inhaled); or through a needle into a muscle (intramuscular) or into a vein (intravenous). Sometimes medicines can be administered right where they’re needed, like a topical antibiotic ointment on a scrape, but most medicines need to enter the blood to reach their therapeutic target and be effective. Those are the ones we’ll continue following, using the common pharmacokinetic acronym ADME:

Pharmacology is the study of how molecules, such as medicines, interact with the body. Scientists who study pharmacology are called pharmacologists, and they explore the chemical properties, biological effects, and therapeutic uses of medicines and other molecules. Their work can be broken down into two main areas:

• Pharmacokinetics is the study of how the body acts on a medicine, including its processes of absorption, distribution, metabolism, and excretion (ADME).
• Pharmacodynamics is the study of how a medicine acts in the body—both on its intended target and throughout all the organs and tissues in the body.

Copper pipes, copper wires, copper…food? Copper is not only a useful metal for conducting electricity, but it’s also an essential element we need in our bodies for a variety of important activities—from metabolizing iron to pigmenting skin.

Copper is required to keep your body going. Enzymes that use copper are called cuproenzymes, and they catalyze a wide range of reactions, including making neurotransmitters and connective tissue. The element is found on the Statue of Liberty’s covering, in wiring and electronics, and in the blue blood of crustaceans. Credit: Compound Interest CC BY-NC-ND 4.0.

If you struggle to wake up in time for school or work or feel drowsy during a trip abroad, your circadian rhythms may be out of sync with your environment. Circadian rhythms are your internal timekeepers, and almost all organisms, from bacteria to plants and animals, have them. You can’t see them, but you can feel their effects—they control when you get sleepy, when you wake up in the morning, and when you feel hungry. Among other signals, the brain uses sunlight to keep time.

The word organic is often used to talk about fruits and vegetables that have been produced in a specific way, typically without the use of synthetic fertilizers and pesticides. But to chemists, organic refers to carbon-containing compounds that are the basis for all living organisms. Ironically, the chemicals prohibited in the farming of organic produce are usually organic molecules.

Organic chemists study, create, and explore carbon-containing molecules. Most organic molecules contain carbon and hydrogen, but they can also include other elements like nitrogen, oxygen, phosphorus, and more. Organic compounds are all around you, from the phospholipids in your body that make up your cell membranes and the NSAID pain reliever that might be in your medicine cabinet to the fabric of the shirt you’re wearing.

While at the grocery store, you’ve likely noticed foods with labels saying they contain antioxidants, but what does that mean? In short, antioxidants are substances that may prevent or delay some types of cell damage. Many foods, including fruits and vegetables, naturally produce antioxidants like vitamins C and E, beta-carotene, and selenium. Our bodies also naturally produce antioxidant molecules such as alpha-lipoic acid, glutathione, and coenzyme Q10.

Antioxidants are united by their ability to donate electrons, which helps them protect the body against reactive oxygen species (ROS). ROS form naturally during exercise, when your body converts food into energy, or during exposure to certain environmental factors such as cigarette smoke, air pollution, and sunlight. These molecules can “steal” electrons from other molecules, and though they aren’t always harmful, consistently high amounts of ROS in your body can cause a condition known as oxidative stress that can damage cells. That cell damage may also lead to chronic diseases, especially if ROS steal electrons from DNA or other important molecules and alter their functions.

The element potassium plays a pivotal role in our bodies. It’s found in all our cells, where it regulates their volume and pressure. To do this, our bodies carefully control potassium levels so that the concentration is about 30 times higher inside cells than outside. Potassium works closely with sodium, which regulates the extracellular fluid volume and has a higher concentration outside cells than inside. These concentration differences create an electrochemical gradient, or a membrane potential.

Potassium is the primary regulator of the pressure and volume inside cells, and it’s important for nerve transmission, muscle contraction, and more. Credit: Compound Interest CC BY-NC-ND 4.0.

“One of the biggest things I hope for in my career is that in 20 years, I still feel the same joy and enthusiasm for research and training that I feel now,” says Prabodhika Mallikaratchy, Ph.D., a professor in the department of molecular, cellular, and biomedical sciences at the City University of New York (CUNY) School of Medicine. Dr. Mallikaratchy talks with us about her career path, research on developing new immunotherapies and molecular tools using nucleic acids, and her belief in the importance of being passionate about your career.

Q: How did you first become interested in science?

A: Growing up in Sri Lanka, I was always a curious child. I remember being drawn to science and math, but there was no particular incident that sparked my interest. By the time I reached high school, though, I had become especially interested in chemistry.

The element manganese is essential for human life. It’s aptly named after the Greek word for magic, and some mysteries surrounding its role in the body still exist today—like how our bodies absorb it, if very high or low levels can cause illness, or how it might play a role in certain diseases.

Manganese is necessary for metabolism, bone formation, antioxidation, and many other important functions in the body. The element is found in strong steel, bones and enzymes, and drink cans. Credit: Compound Interest CC BY-NC-ND 4.0.