This paper covers a potential causal link between cellular senescence and various aging phenotypes. Removing senescent cells exhibiting the kinase inhibitor and senescence biomarker p16 delayed the onset of age-related phenotypes in mouse skeletal muscle, adipose, and eye tissues.

Interesting analysis on longterm trends in human life expectancy

Neprilysin is an enzyme responsible for breaking down several key peptides, including B-type natriuretic peptide (BNP). BNP is a hormone released primarily from the heart’s ventricles in response to increased pressure and fluid volume. It acts as a signal to the kidneys to help reduce this overload by promoting diuresis (pee out fluid/volume) and natriuresis (pee out sodium). BNP also helps relax blood vessels (vasodilation), which lowers the overall stress on the heart.

The Evolution of BNP: Designed for Acute Response From an evolutionary standpoint, BNP’s role in fluid regulation likely evolved to address acute situations, such as sudden increases in blood volume or salt intake. For our ancestors, these situations might have been rare but critical, like consuming large amounts of water after periods of dehydration or reacting to sudden trauma or infection that caused fluid shifts.

BNP’s ability to trigger diuresis (fluid removal) and natriuresis (sodium removal) was a short-te

Lipemia to Ketosis: A Historical Journey Through Fats in the Blood Let’s take a deep dive into the world of fats in the blood, starting with the classic historical experiments on lipemia and ending with how ketosis and exogenous ketones fit into the picture of modern metabolic health. .

Lipemia: The First Observations of Fat in the Blood The story of lipemia—the condition where blood becomes milky or cloudy due to high levels of fat—begins in the early days of lipid metabolism research. Scientists noticed that after a fatty meal, blood drawn from patients sometimes had a creamy layer floating on top. This layer turned out to be chylomicrons, large fat particles that carry triglycerides (Fat molecules) from the intestines into the bloodstream after eating.

In other cases, blood became uniformly turbid or milky—this was due to smaller fat particles (like VLDL and triglycerides) staying suspended in the liquid portion of the blood. These e

Troponins: The Heart of Cardiac Diagnostics

Troponins are a big deal in medicine, especially when it comes to diagnosing heart attacks. Let's break down the basics of troponins, how they work in the body, and how we detect them in the lab.

What Are Troponins? Troponins are proteins involved in muscle contraction, found in both skeletal and cardiac muscle. They’re part of the troponin-tropomyosin complex, which helps regulate muscle contraction by interacting with actin and myosin.

There are three types of troponins:

Troponin C (TnC) – Binds to calcium, triggering muscle contraction. Troponin I (TnI) – Inhibits muscle contraction in the absence of calcium. Troponin T (TnT) – Anchors the troponin complex to the muscle fiber.

For cardiac diagnostics, we focus on cardiac-specific troponins: Troponin I (cTnI) and Troponin T (cTnT). These versions are unique to the heart muscle, making them incredibly important markers for detecting cardiac injury. When the heart is damaged, lik

Why the Interventions Testing Program (ITP) Is the Gold Standard for Longevity Research

https://www.nia.nih.gov/research/dab/interventions-testing-program-itp/supported-interventions

If you’re following the latest trends in longevity research, you’ve probably heard about a few "miracle compounds" like metformin, resveratrol, and NAD boosters. But let’s get real—when it comes to real preclinical data that actually holds up, nothing beats the Interventions Testing Program (ITP). And no, we’re not here to play along with the hype around these compounds that often don’t deliver in the lab.

What Is the ITP and Why Should You Care?

The Interventions Testing Program (ITP), run by the National Institute on Aging (NIA), is a uniquely well-designed testing platform that focuses on evaluating the effects of different compounds on lifespan and healthspan in outbred mice (meaning they have genetic diversity more like human populations, unlike the typical inbred strains). This gives

I got into an interesting discussion at work about an MRI sequence I've never used before. For context, I did a bunch of brain imaging in grad school, and now at work I'm encountering things that aren't the brain. Shocking.

The technique in question is trying to look at the amount of cartilage in a joint. I assumed the best way to identify potential problems with the MRI is to use a phantom like this one: https://www.truephantom.com/product/adult-knee/. We did this in grad school, but our phantom was basically an expensive jug of fancy water, which, apparently, looks enough like a brain to calibrate the machine.

It turns out the hospital just takes a random resident, puts them in the MRI, and takes MRIs of their joints. I'm assuming it's because the hospital doesn't want to pay $10k for a fancy fake knee.

So now I'm curious, if the radiologists and radiology-adjacent folks are out there, how many different phantoms do your teams own?

Let’s Talk Blood Collection Tubes and What the Colors Mean!

Ever wonder what those different colored tops on blood collection tubes actually mean? Each color tells us something important about what’s inside the tube and how the blood will be processed. Let’s break it down, adding some cool science along the way!

Red Top – No Additive Your blood is your blood! This tube contains no additives. A key property of blood is clotting—when exposed to air (more accurately activating factors), blood naturally forms a clot as platelets and clotting factors work to seal off a wound. In the lab, we let this clotting happen. As the blood clots, it traps certain components, like cells and proteins, forming a pellet. What’s left behind is serum, which is the liquid portion of blood without cells or clotting factors. This is used for tests like liver function or kidney panels where serum chemistry is important.

Gold or Tiger Top (SST) – Serum Separator Tube Think of this as “Red with a plug!

Longevity and lifespan are a real hot topic right now. The amount of interest in the field has been increasing significantly and several labs are cranking out exciting new research. However, there is a lot of data out there and it can be tricky to interpret promising data from the noise. In response to this, a few researchers came together and put out a preprint on how to best gauge the quality of longevity interventions.

https://www.sciencedirect.com/science/article/abs/pii/S1568163724003301

They argue in favor of choosing long lived controls, in this case lab mice, as a better marker for the robustness of any longevity intervention and state…

“In the absence of independent replication, a putative mouse longevity intervention should only be considered with high confidence when control lifespans are close to 900 days or if the final lifespan of the treated group is considerably above 900 days.”

This is the 900-day rule. Now, why is this important? Many studies in longevity researc

Full disclosure, this is outside my area of expertise (whatever that means…).

I want to talk about the thymus and its importance in aging. I recently came across a fascinating paper that builds on a model of human lymphopoiesis across development and aging, and I wanted to share it with you all: (https://pubmed.ncbi.nlm.nih.gov/38908962).

The thymus plays a key role in the immune system, especially in the production and maturation of T-cells, which are crucial for immune responses. One of the things that really piqued my interest is how the paper discusses developmental transitions in the thymus and how these changes potentially affect the immune system throughout life. It’s especially interesting how thymic involution with age may impact immune health, and how this could tie into the overall aging process.

To me, it's wild that the thymus pretty much "dies" before we’re even out of our teens... Seriously, look at Figure 5. This idea has kept me up at night for about a decade now. A

Hello Mainlined Science! We’re always looking for new topics and ideas to dive into, so we’d like to start getting some engagement! Got a question, a research area you’re curious about, or just something science-related that you’ve been pondering? Let’s talk about it! Even if it's outside our fields, no wrong answers!

Whether it’s a specific field you want to explore or a “random thought of the day,” feel free to start up the chat, we will reply. We’re here to start discussions, share knowledge, and learn together. Drop your ideas below—there are also no wrong questions!

I’m also thinking about occasionally hosting some hypothesis-generating sessions, starting small research projects, and maybe even setting up a little DIY lab. If there’s interest of course.. Maybe we could get into some 3D printing or simple bio experiments too! Let's see where this can go. Let's get the hive mind goin!

Ok, so I had a patient. The actual history isn't terribly important because this sort of thing happens relatively frequently, but to give you a quick one-liner: he was an older male with rheumatoid arthritis admitted for Staph bacteremia. In cases of blood infections, we order tests called "clearance cultures" to track and confirm that the organism we're fighting disappears with treatment. In this case, 1 out of 4 of these samples tested positive for a potential Bacillus species—the genus to which anthrax belongs. That being said, completely inert species of Bacillus are common contaminants in this setting, and the fact that only 1 out of 4 samples tested positive definitely makes you think this is such a case of contamination.

However, we treat it as if it were anthrax until we're completely certain it isn't. It's Schrödinger's anthrax! After all, you don’t want to be the lab that missed anthrax.

Bacillus anthracis Identification Colonies of B. anthracis appear non-hemolytic, consis

What is Fasting and why do so many people seem to be into it?

There are many flavors of fasting, but they can be categorized into two main categories: intermittent fasting (IF) and time restricted eating (TRE). IF is defined as eating once every 24hrs and TRE is characterized by a shortened eating window, usually seen as 8hrs eating and 16hrs fasting.

IF also know as one-meal-a-day (OMAD) and TRE have been farily popular over the last few years. They gained a lot of traction, almost a decade ago, with the hope that fasting mimicking diets could help with age related declines. The overall consensus now is that this type of fasting only imparts lifespan health benefits if you also restrict total calories. However, the hype was strong and most of these dietary methods are still championed today as a way to promote health. But can they actually provide any health benefit? Well, it depends. In the scope of nutrition and health, there's no better alternative than a well balanced diet.

OK, Time for Something Random: Lyme disease and its strange connection to lizards.

Lyme disease is a big deal. Especially, or at least historically, here on the east coast US. Did you know that some animals can actually cure infected tick carriers!? I didn't either.

In parts of California, western fence lizards play a surprising role in controlling Lyme disease. When ticks feed on these lizards, a protein in their blood kills the bacteria (Borrelia burgdorferi) that causes Lyme disease. Some factor in the lizards blood is ingested and kills the bacteria present in the gut of the tick.

To conclude, nature is wild. Much of our innovation in biology/medicine, including CRISPR (see earlier related posts) and the majority of our antibiotics, aren't so much inventions but are more accurately 'discoveries.'

Relevant papers I happened upon: https://pubmed.ncbi.nlm.nih.gov/9488334/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5413869/

Let’s continue our dive into gene therapy with one of my favorite papers. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6876218/

In this study, researchers delivered three longevity-associated genes (FGF21, αKlotho, and sTGFβR2) to mice using a gene therapy cocktail. These genes target metabolism, heart function, and kidney health—three areas that typically decline with age. Here’s why this is a big deal:

Obesity & Diabetes? Reversed. Mice fed a high-fat diet lost weight and saw their diabetes symptoms disappear, just by tweaking how their cells handled energy.

Heart Failure? Improved. The therapy improved heart function by 58%, meaning it could help tackle the leading cause of death worldwide.

Kidney Disease? Protected. Mice treated with this gene therapy avoided the typical kidney damage seen with age-related conditions.

What’s most exciting is that a single gene therapy cocktail—combining just two of the three genes—was able to treat all of these diseases simultaneously. Imagine

Let’s talk CRISPR-Cas9 and why it’s one of the most significant breakthroughs in modern biology.

At its core, CRISPR-Cas9 is a tool for precise genome editing. Before CRISPR, genetic modification was a slow, expensive, and often imprecise process. CRISPR changed the game by allowing scientists to cut DNA at specific sites, guided by an RNA molecule that can be customized to target nearly any gene. Once the DNA is cut, it can be repaired in a way that adds, deletes, or alters the genetic sequence. This kind of precision has opened up endless possibilities.

Why is this such a big deal?

Speed and Efficiency: CRISPR allows scientists to make changes to the DNA of organisms in weeks, not years. You want to knock out a gene? You can do that. Want to introduce a new one? Done. The speed and flexibility are revolutionary compared to older methods.

Precision: CRISPR can zero in on specific genes with high accuracy, reducing the risk of off-target effects (though this is still an area of res

This is a preprint, which means that the article has not been peer-reviewed yet. This is all part of the normal process, researchers will often present their findings before their work is published.

Here the deets!

The AgelessRx-sponsored Participatory Evaluation of Aging with Rapamycin for Longevity (PEARL) trial was a 48-week randomized, double-blind, placebo-controlled trial investigating the safety and potential efficacy of different intermittent rapamycin doses for mitigating signs of aging.

More info!

https://clinicaltrials.gov/study/NCT04488601

https://agelessrx.com/results-of-the-pearl-trial/