I’m missing an organ and scared... TO THE LAB!

I used to dream I would one day cure diseases. Now that I have learned a thing or two, I have realized many diseases are extraordinarily complex, as are their treatments. On top of that, can you even imagine how complex and varied human beings are?

What do you mean I don’t need a gallbladder? 

I didn’t have to imagine it for long. Back in 2021 I became terribly ill. I couldn’t eat, dropped fifty pounds, and remained undiagnosed for months. With every new specialist and inconclusive test, I began to feel as though medicine was failing me until a surgeon finally offered a solution: “Let’s just take that ole gallbladder out!” At the time I immediately took that chance. I was very fortunate it eliminated my symptoms, but looking back I am haunted by my lack of answers, especially now as I’ve learned more about the molecular impacts that decision could have on my body.

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Any who... where am I now? I am a Ph.D. student in the lab of Dr. George Sutphin where we utilize a “simplistic” model organism, C. elegans (aka “worms”), to study aging and explore ways to ease the burden of age-related disease. Even though human disease is a giant mountain to climb, I decided to burrow (that’s funny because worms do that). Our lab cares about not just living longer but living healthier longer.

Of course, the personal questions never fully went away. They kept circling in the back of my mind: Why was I even sick? Why couldn’t they find the cause? What do you mean I don’t need a gallbladder? 

A lot of signs might potentially point to “uh oh” for old Hannah Majors. Life did not exactly go back to normal after losing my bile storage. Without a gallbladder, bile flows constantly into the intestine, which can cause all sorts of digestive chaos. Many people just get acid reflux or food sensitivities. I, on the other hand, also get the joy of thinking about the gut–brain connection and what long-term effects this bile imbalance might have. Some studies even suggest gallbladder removal can affect neuronal health in older patients. This is why I say, “uh oh.” 

Luckily for me, I am a molecular biologist! Not knowing is my mortal enemy. So, this sense of “doom” has naturally led to me becoming highly interested in how small molecules we encounter every day through digestion impact our health as we age.

Diet, fats, and aging in worms (for now)

We’ve all seen health influencers arguing about which cooking oil will murder you or not. They can keep debating, but I decided to study how ingested lipids actually affect whole-body and neuron health using worms. Lipid signaling molecules and the proteins they interact with form networks that help neurons survive, communicate, and handle stress. Prior research suggests that tuning these lipid pathways extends healthy lifespan.

One question that drives my work is how aging neurons maintain metabolic flexibility. In C. elegans, this is largely impacted by a molecule named NHR‑49, a hormone receptor that tells cells how to process fats, make energy, and respond to stress. When worms are young, NHR‑49 keeps everything running smoothly. But as they age, this system starts to falter, and their cells become less efficient at using the fats they eat.

Diet is one of the most direct ways to modulate this pathway. The fats an organism consumes feed directly into the pathways NHR‑49 controls. Some dietary lipids help NHR‑49 keep metabolism flexible and healthy. Understanding which lipids help and which harm is essential to figuring out how diet influences brain aging. Too much cholesterol in the wrong place can fuel inflammation and amyloid buildup in Alzheimer’s. Omega-3 fatty acids protect neurons, while some saturated fats make them stiff and slow with age. Because diet shapes metabolic flexibility, if I change what a worm eats, can I strengthen or rescue aging neurons?

To find out, I’m feeding worms different types of fats and tracking how long they live and how well they age. I’m also putting them through what I call the “sensory Olympics”, a set of challenges that test their memory, their ability to avoid danger, and how gracefully they move as they get older. Because worms are transparent, I can even tag certain molecules with fluorescent markers and watch metabolic signals flicker inside their neurons in real time.

Moving forward, I hope to study patient-derived models to understand how diet and lipids affect individual brains. Genetics, environment, and habits shape digestive health and brain aging in diverse ways. No two people age the same, and no two sets of neurons respond to stress in the same way.

Neurons rely on a specific lipid balance to stay stable. When that balance slips, everything gets shaky. Just as a coach tailors training to each athlete, the best medical approaches won’t be one-size-fits-all. And honestly, that gives me hope. If we can understand how lipids shape the aging brain, we can design tailored treatments to help the people, and worms, who need them most. 

So, while I may have lost an organ, I gained a purpose: figuring out how to help aging cells hold themselves together just a little longer. It is my hope that one of these interventions might just give a tired old worm back the same wiggle it had in its prime.