Las alucinantes terapias génicas están en el horizonte

Penning Dr. B’s newsletter for 100 weeks straight keeps a writer attuned to the coolest healthcare happenings. To recognize this milestone (!), let’s take a nerd dive into medicine’s fascinating frontier—genetics.

At a rapid pace, researchers are uncovering mutations to better assess disease risk (like the 12 linking women of African descent + breast cancer) + making therapies to repair mutations (like restoring hearing to toddlers with faulty OTOF genes). We’ll look at those with sweeping future potential. Then, close with healthcare news to know now.

But first, jump into your weekly…

• Checkup: weird + wonderful health tips
• Gene Jackets: brains + HSV-1 + back pain
• Healthcare: pill access + mask studies + fish oil risk

The Checkup

• What happens when someone dies on a plane?
• They’ve found microplastics in human testicles!
• Why ingrown hairs happen + how to prevent them
• Explore the twisted, misunderstood history of carbs
• Get a sensory feel of podophobia—a fear of feet
• A cool interactive guide to at-home first aid basics
• Hit the beach with an 8-minute, 8-move workout
• 6 key facts about abortion laws + the elections 
• Why + how you should slow down your run pace
• Do you have a hangover or alcohol intolerance?
• How to keep food safe outside in hot weather

Crossing the brain barrier

Gene therapies for brain diseases like Huntington's, ALS and Parkinson’s are limited because high amounts can’t penetrate the blood-brain barrier—the thin membrane that separates blood + other large, water-soluble molecules from the brain. But a team of MIT and Harvard researchers may have found a new mode of transportation.

Adeno-associated viruses (AAVs) are single-strand DNA viruses. They don’t cause illness on their own + can be programmed to deliver genetic material into cells. The team looked for an AAV that can specifically bind to the transferrin receptor—a carrier protein that can cross the blood-brain barrier. They chose this receptor because they can modify mice to express the human form of it + then accurately test how it carries a coded AAV to the brain. Eventually, they uncovered BI-hTFR1.

In tests, AAV BI-hTFR1 landed in the brains + spinal cords of the humanized mice in far higher amounts than mice injected with AAV9—an AAV used to deliver current gene therapies. It reached essential brain cells and delivered 30 times more copies of healthy GBA1 genes than AAV9. As those with brain disease often have GBA1 mutations, delivery of healthy copies could become a valuable treatment.

Therapies delivered to the central immune system (via the brain) put less strain on the liver, which means potential therapies delivered this way could be more effective and have fewer side effects.

Exciting stuff! Read more at the Broad Institute.

A herpes cure?!

Herpes simplex virus 1 (HSV-1) hides out in nerve cells. When triggered, it causes cold stores or bumps around the genitals. It has no cure—but researchers at the Hutch Cancer Center in Seattle are getting close to one!

The team created a gene-editing molecule mixture that includes a lab-modified virus (a vector) + DNA enzymes (meganuclease). Injected into the blood, the vector finds the herpes virus, and the meganuclease cleaves at two parts of its genetic coding.

Damaged beyond repair, the virus can’t reproduce. Then, the immune system recognizes the damage and kicks in to kill it.

In mice, this eliminated 90% of HSV-1 after oral breakouts + 97% after genital breakouts in one month! It also significantly reduced reproduction + viral shedding—which is vital for lowering transmission rates.

There’s a long way to go before treatment could be ready. Learn more at The Hutch.

Healing disk damage!

Once the cushioning between our spinal disks deteriorates, there’s no rebuilding it, leaving us with little relief but PT and painkillers. But a team at Ohio State University might be on the road to curing the cause.

The team created nanocarriers—small transport cells—from connective-tissue cells called fibroblasts. Then, they loaded the cells with material to help the body produce FOXF1, a transcription factor protein that encourages tissue growth + development and decreases as we age.

They injected the FOXF1 nanocarriers into mice when their backs were injured. (We owe so much to mice, sigh.) Twelve weeks later, the disks of the mice had restored function + were plumper and more stable compared to controls. They also showed fewer signs of pain!

Again, treatments for humans with back injuries are years away. And the researchers want to test potential regrowth for age-related degeneration. But this therapy could potentially teach the body how to repair itself, marking massive improvement for the 40% of people who experience low back pain because of disk degeneration.

Healthcare 411

Abortion pills may become controlled substances in Louisiana (NY Times). A bill passed in the state’s Republican-led house that would categorize mifepristone + misoprostol as Schedule IV drugs, reserved for those with addictive or abusive potential. Should it pass the Senate, Gov. Jeff Landry will most likely sign it into law, making anyone who possesses the pills without a prescription subject to fines and jail time.

Masks and respirators for prevention of respiratory infections: a state of the science review (ASM). An analysis of over 100 studies found that masks effectively reduce respiratory disease transmission when worn correctly + consistently. It also found that mask mandates reduce community transmission levels and that N95/KN95 masks are more effective than medical or cloth masks. The authors hope the findings will encourage research to improve mask materials, community transmission, disability communication support + environmental impact.

Why fish oil supplements can be dangerous for the heart (Time). A study of 400K adults found that taking fish oil supplements increased atrial fibrillation and stroke risk for people with no history of heart conditions. While supplement dosage was not monitored, the results suggest excess levels of omega-3 fatty acids were at play. So, the American Heart Association recommends that healthy people eat fish 1-2 times per week while those with heart conditions continue to have supplementation monitored by a provider.