SCROLL NEWS / DISCOVERY
Search headlines
Find the stories shaping the conversation.
Results for " regrow " 31 found 🔀 AI-powered Shuffle
Scientists Discover Groundbreaking Clues to Tissue Regrowth and “Immortality” in the Ocean
Sea cucumber tissue kept growing for more than three years after removal, surviving in seawater teeming with microbes. Like Thing, the disembodied hand in The Addams Family, a severed piece of sea cucumber tissue kept living without the body it came from, prompting scientists to describe the animal as a “real-life zombie.” Weeks after being
Goodbye joint replacements? Stanford scientists found a way to regrow cartilage and stop arthritis
Scientists have found a surprising way to regrow damaged knee cartilage by blocking a protein that becomes more abundant with age. In old mice, the treatment restored naturally lost cartilage and also helped prevent osteoarthritis after ACL-like knee injuries, while human cartilage taken from knee replacement patients began producing new, functional joint cartilage after exposure to the same inhibitor.
Why scientists are stoked about mysterious black hole stars
You've heard of black holes. You've heard of stars. But have you heard of the newly discovered black hole stars that may explain multiple mysteries of the universe? We just did and we're honestly freaking out about it. Learn everything you need to know about it in this episode. Plus, hear some other cool stories fresh off the presses: Which exercise can help reduce your risk of dementia and how shrews shrink — and then regrow — parts of their body throughout the year.Interested in hearing more reporting on space, scientific mysteries or other emerging science? We want to know! Email us what you'd like us to talk about at shortwave@npr.org!Support public media with NPR+ and enjoy perks for over 25 podcasts like this one. This show’s perks include sponsor-free listening. Learn more at plus.npr.org.
Scientists Just Found a Way to Regrow Your Tooth Enamel—And It Could Be Available Next Year
The hardest substance in the human body, tooth enamel, has a major weakness—it can’t regrow. Science is working to fix that.
When we bring back forests and wetlands, some tinier species may be missing
A regrown forest can look tall, lush and green. Restored wetlands can buzz with insects and flutter with birds. But scientists looking more closely are finding that some of their smallest inhabitants — mosses, lichens and algae — are still missing.
Zombie sea cucumbers and the future of tissue engineering | Investors Lab
It's pretty cool, but not exactly news, that lizards can regrow their tails and starfish can regenerate arms. However, the lost or discarded body parts typically decay and die within a few days or weeks. Not so for those of at least one kind of sea cucumber. Researchers have found that detached tissue from these marine invertebrates can remain alive independently for years. Their findings could have a real impact on how we understand tissue culture, regeneration and aging in medical science. Saugat Bolakhe takes us beneath the surface for SN.
Scientists are regrowing human teeth
While teeth play a greater role in health than many realise, current dental solutions for tooth loss are temporary and subpar. What if we could regrow our teeth instead?
Scientists are regrowing human teeth
While teeth play a greater role in health than many realise, current dental solutions for tooth loss are temporary and subpar. What if we could regrow our teeth instead?
Ice, Ice, Maybe? Scientists Are Trying to Regrow Ice in the Arctic With Simple Tech
Arctic sea ice is disappearing at a worrisome rate. What if there were a way to slow that down?
Stanford scientists regrow lost cartilage and reverse arthritis in major breakthrough
A new treatment that blocks an aging-related protein restored lost cartilage in old mice and helped prevent arthritis after knee injuries. Human cartilage samples showed similar signs of regeneration, raising hopes for a future drug that could repair joints instead of replacing them.
Ancient Chinese medicine could transform hair loss treatment
A traditional Chinese medicinal root used for over a thousand years is attracting new scientific attention for its potential to combat hair loss. Studies suggest Polygonum multiflorum can block harmful hormones, activate hair-growth signals, protect follicles, and boost blood flow to the scalp. Researchers say the herb’s effects align remarkably well with both ancient descriptions and modern hair biology.
Scientists find 'holy grail' of genes that could regrow human limbs
Scientists Say They’ve Invented a Serum That Activates a Dormant Ability to Regrow Lost Limbs in Mammals
"The capacity is not absent — it's just obscured."
Scientists found the “holy grail” gene that could one day help humans regrow limbs
Scientists studying axolotls, zebrafish, and mice have uncovered a shared set of genes that may one day help humans regrow lost limbs. By identifying powerful “SP genes” involved in regeneration, researchers discovered that disabling these genes stopped proper bone regrowth in salamanders and mice. They then used a gene therapy inspired by zebrafish biology to partially restore regeneration in mice, marking a major step toward future treatments that could replace damaged limbs with living tissue instead of prosthetics.
Scientists Discover Stem Cells That Could Regrow Teeth and Bone
Scientists just uncovered the cellular “blueprint” that could one day let us regrow real teeth.
You Can Actually Regrow Your Fingertips. Scientists Just Figured Out How.
You can regrow damaged skin in the area, sure—but also bone, tissue, and nerves.
What if humans could regrow tissue? New study moves science closer
For centuries, the inability to regrow lost body parts has been considered a defining limitation of humans and other mammals. While animals like salamanders can regenerate entire limbs, humans are left ...
What if humans could regrow tissue? Texas A&M study moves science closer
Researchers have successfully regenerated skeletal and connective tissue — even if not perfectly formed — demonstrating the next, critical step in limb regeneration.
This comet is ‘regrowing’ its tail in space and scientists compare it to a lizard
Science News: It has long been an exciting area of study for many people to observe comets in the night sky, but according to a recent observation as published in ‘.
Federal Agency Unveils Three Potential Osteoarthritis Treatments
With funding from ARPA-H, three teams of researchers have regrown bone and cartilage, even entire knees, in animal studies. Human trials are not far off.
Nissan Americas head: 'We've had some pretty good success regrowing the business'
Nissan Americas chair Christian Meunier came to the New York International Auto Show with a simple message: The brand is back, and it's building in America.
This CBS Graduate Student Studies How Bodies Regrow
Iris Juanico was drawn to science by her innate curiosity. “I never stop asking questions,” said Juanico, with a laugh. “I was drawn to science as a child because it involves asking a lot of questions.”
Your Thymus and Your Healthspan
Our thymus gland plays a central role in the development or our immune system, specifically for supporting T cell development (how these cells got their name, maturation and differentiation in the thymus) and discriminating between self and foreign, non-self antigen proteins with production of dendritic cells. As we age, our thymus gland shrinks—the process known as involution—with progressive change from spongy to fatty tissue, with loss of functionality. But this process, with respect to timeline and extent, markedly varies from one person to the next. And to make things even more complicated, our thymus gland anatomy and precise location in the chest also is highly variable. So the famous Frank Netter diagrams from the 1960s (such as at left below) don’t capture the remarkable heterogeneity that a random set of 12 chest CT scans (below at right). What I consider as 2 landmark papers in Nature this week (here and here) used AI to quantify health of the thymus in 2 large cohorts, and then correlate the metric to a broad array of health outcomes. In this edition of Ground Truths, I’m going to cover three questions: (1) How was thymus health determined by AI?; (2) How is thymus health linked to key clinical outcomes? and (3) Are there ways we can promote a healthy (aka rejuvenate) thymus gland in our later years? Subscribe 1. How was thymus health determined by AI? This was accomplished by extensive work developing and validating an AI pipeline for 2 stages, the first for localization and segmentation of the thymus bed, and the second to quantify a digital marker, termed the thymic health score. There’s a lot to this algorithmic development, so I won’t go into all the details, but just provide a rudimentary outline of what was done. The 1st stage used supervised learning with 2 radiologists reviewing 2,461 chest CT scans. That work trained a 3D U-Net model to automatically identify the thymic bed’s 3D cropped region using center of mass coordinates, which reached 99.8% accuracy. The 2nd stage used a foundation model that was pre-trained with SwAV (which stands for Swapping Assignment between multiple Views), a self-supervised model, that generated a high-dimensional thymus representation of 4,096 features. That compares to the radiology reductionist and subjective scoring of 0 to 3 where 0 means the thymus is fully degenerated and fatty, and 3 is considered dense, intact glandular soft tissue. Notably, the self-supervised learning (SSL) performance was superior to supervised (AUC ~0.75 vs 0.55, respectively) reflecting the shallowness of the 0-3 classifier vs SSL’s holistic, self-taught AI. The thymic health score ranged from 0 to 100, with the highest number indexed to fully preserved thymic health. The algorithmic work extended to explainability with both Shapely value distribution, meaning the model was holistic not relying on any “magic” pixel, and occlusion sensitivity, demonstrating the model’s performance was not affected by ribs, sternum, lung tissue, but rather focused on the thymic bed directly. Below are a few saliency maps from the occlusion sensitivity that indicate the thymic bed focus, not affected by neighboring structures, using the jet color scale. Now the AI was ready for processing ~25,000 CT scans, each over 30 MB files, from the 2 large participant cohorts to provide a thymic health score, it did so in less than 14 hours, which is less than 2 seconds per scan! Share 2. How is thymus health linked to key clinical outcomes? The two cohorts were the National Lung Screening Trial, NLST (N=25,031) and the Framingham Heart Study, FHS (N=2,581) each with baseline demographics and long term follow up of >12 years for health outcomes. From the NSLT, you can see below that increased age and body-mass index were correlated to reduced thymic health. And, overall, men had reduced thymic health scores compared with women. There are a lot of graphs in the paper for outcomes, for both the NLST and FHS cohorts. To simplify the major outcomes, below is a composite Figure with striking reduction of all-cause mortality and for the different causes of death. The results were consistent between the 2 cohorts. For example, the cardiovascular mortality hazard ratio average was 0.57 in NLST and 0.38 in FHS (weighted to be 0.53 for the aggregate). The reduction of mortality also extended to digestive diseases and pulmonary disease (data not shown below). Lung cancer incidence was reduced by 36% for high vs low thymic health (Figure below, with a panel -incidence and b panel-mortality, adjusted for age, sex, BMI, smoking status). Notably, there was a smoker’s paradox: lower incidence and improved survival for lung cancer in smokers who had a high thymus health score. Smoking was associated with lower thymic scores whereas alcohol was not. Higher thymic health was linked to higher HDL cholesterol, lower triglycerides, lower fasting blood glucose, and lower systolic and diastolic blood pressure. Inflammation biomarkers, such as C-reactive protein and interleukin-6, were elevated in the people with lower thymic health scores. In their second paper, the same team looked at the relationship between thymic score and outcomes for 3,476 patients receiving cancer immunotherapy. The non-small cell lung cancer progression-free survival was reduced in patients with low thymic health score. A parallel relationship for survival was seen for other types of cancer including melanoma, breast, and kidney with a 44% lower risk among high thymic scores (Figure). A similar pattern was seen with different immune checkpoint inhibitors. The thymus health score outperformed programmed death ligand-1 (PD-L1)and tumor mutation burden (TMB) assay of the tumor and was an independent prognostic marker of progression-free survival. In this dataset, a direct connect with thymus score and adaptive immune function was noted with a correlation before cancer treatment for both T-cell diversity and thymus T-cell production (a metric known as T cell receptor excision circles). Thymus Removal Study There is a highly relevant citation about thymus function before moving onto ways to rejuvenate it. In 2023, a very important study of thymus removal during cardiothoracic surgery was published, with 1146 patients undergoing thymus removal vs 1146 matched controls (mean age 55 years). The adverse outcomes for thymus removal were striking, with a 2.9 higher risk of all-cause mortality and doubling of cancer incidence, 1.5 fold increase in cancer mortality, and 1.5-fold increase in autoimmune diseases. The immune function showed marked compromise after thymus removal, as reflected by CD4+ and CD8+ T cells (Figure below) Share Ground Truths 3. Are there ways we can promote a healthy (aka rejuvenate) thymus gland in our later years? In recent months we’ve learned a lot about the process of thymus involution and the pathways by which this may be modulated. Thymus involution is primarily due to loss to thymus epithelial cells (TECs) and there are 2 subtypes with different functions: the cortical, responsible for positive selection of T cells, and the medullary, for negative selection. When adipose tissue infiltrates the thymus, thymic adipocytes are pro-inflammatory, knocking out T-cell output. Likewise, systemic inflammation, or “inflammaging,” from smoking, obesity, and chronic stress promote thymic adipocytes. Now, from preclinical studies, we know about key pathways that account for these processes. Historically, back in 2014, FOXN1 was recognized as a single master transcription factor essential for TEC function, with studies in mice with forced FOXN1 upregulation leading to thymus regeneration. That laid the foundation for potential regrowth of quiescent thymus cells. It took awhile to find pathways to accomplish this goal and to even refute its role as the master regulator. The Liver-Thymus Axis Feng Zhang and his team recently showed that injection of an mRNA vaccine to the liver encoding DLL1, IL-7 and FLT3-L in combination, factors known to support thymopoiesis (Figure), successfully enhanced immune function in aged mice. However, the effect was transient. The FGF21 Story Two reports in 2025 addressed the thymus gland’s production of FGF21, a growth factor (fibroblast growth factor 21) and its control of thymus involution. This growth factor is also produced by the liver, but it doesn’t have impact on the thymus in aged rodent models. In contrast, The liver’s hepatocyte growth factor (HGF) has been shown to reverse senescent TEC structural changes. Growth hormone stimulates production of insulin growth factor-1 (IGF-1) in the liver and the thymus. Two small studies in human participants (TRIIM, for Thymus Regeneration, Immunorestoration, and Insulin Mitigation) of 6 and 50 people, respectively, treated with combined human growth hormone, metformin and DHEA, suggested the potential of slowing epigenetic aging and improving thymus mass and function. But the combination of drugs, small sample, and lack of controls make conclusions murky. Increased thymus FGF21 led to increased CD8 T cells in old mice and extended healthspan and improved physical performance. Building on the previous FOXN1 data, ablation of β-klotho, the obligatory co-receptor for FOXN1, accelerated thymic aging. The benefit to FGF21 was confirmed in a companion paper using an FGF21 knock-in mouse model showing thymus enlargement and increased TECs throughout the lifespan. (schematic Figure below). The accompanying editorial for these 2 papers speculated: “The proposed link between age-associated thymus involution and organismal aging is intriguing, and suggests we might seek to achieve systemic rejuvenation by counteracting thymic involution.” Other Factors Lessons from the Axolotl (Mexican Salamander) In an elegant set of experiments of the axolotl (Figure), known for its complete thymus regeneration after total surgical removal, mediators were identified. Surprisingly FOXN1 was dispensable. But midkine, a growth factor, appeared to be the driver, the initiator of thymus cell growth, survival, and repair. Other components that contributed were Postn+ (periostin-expressing mesenchymal niches) and Ccl19, a chemokine protein from the bloodstream. RANK and RANKL RANK (receptor activator of nuclear factor κB its ligand (RANKL) have been considered key regulators of medullary TECs. In a study of both aged mice and human thymus cell cultures, their key role was confirmed, with multiple benefits of resorting TEC function, recruitment of progenitor cells, and T cell development. Subscribe Summing Up This body of work strongly supports the health of the thymus gland as a critical regulator of human healthspan, not just a correlate or link. The new landmark studies are reinforced by the regenerative biology experimental models that have shown, via an array of mediators, that healthspan of aged mice is at least in part dependent on thymus gland function and its critical role for maintaining adaptive immunity. It sure seems that we’d be better off having an immune reservoir of naive T cells instead of a profile in older adults of exhausted, low quality, memory T cells, with a senescent phenotype. It is striking that we ignored the importance of the thymus gland for many decades. A wake-up call was the results of the thymectomy matched control study reviewed here, with the opposite of high thymic health score improved health outcomes. The convergence of AI and healthspan here is notable. The exceptional and laborious work for developing and validating (no less explaining) the AI to quantify thymus health set the foundation for probing the connect the major health outcomes in two cohorts with extensive follow-up. We’ve never had a way to meaningfully quantify the thymus gland before, so this represents important leverage of supervised, self-supervised, and transformer models. The study wouldn’t have been possible without AI. And it begs the question as to whether there are ways we can maintain our thymus at a high health score. But it’s not so simple to rejuvenate our thymus. There are multiple risks including the induction of autoimmunity, increasing the risk of cancer, and inducing a pro-inflammatory state. For example, factors that increase TEC proliferation could compromise the medulllary negative selection process and leak out auto-reactive (self-attacking) T cells. Thymic cells could be induced to proliferate, but we know, for example, that growth hormone and IGF-1 are associated with an increase risk of cancer. If thymus rejuvenation doesn’t clear out the accumulated senescent cells in older adults, then inflammation within the gland could block the production of TECs. Keeping these risks in mind, we now have identified many ways to keep our thymus healthy as we age that undoubtedly will be tested in clinical trials going forward. Ultimately, the benefit-to-risk tradeoffs will be defined. In the meantime, we have desperately needed an immunome. As I’ve stressed in multiple prior Ground Truths, we have no test in the clinic to assess a patient’s immune status! It was very encouraging for me to get an email from Hugo Aerts, the senior author of the landmark papers in the days after they were published: “I also wanted to say that your Substack on “Why We Need an Immunome” was inspiring for this work. We found it a very compelling perspective and greatly enjoyed reading it.” Just having an assessment of a person’s immune status via a chest CT scan, with millions of these performed per year, might help in guiding the right immunotherapy for cancer (e.g. more intensive, combinations for those with low thymic health scores) and help define people who are increased risk for age-related diseases of cancer, cardiovascular, and neurodegenerative. The main theme of Super Agers is that we now have many layers of data (genetics, proteins, biomarkers, organ clocks that can be integrated via multimodal AI) for us to define a person’s specific risk decades before one of these age-related diseases leads to symptoms, enabling prevention. From the new studies this week, we can add thymus health score as yet another way to understand a person’s risk, a window into their adaptive immune system and healthspan. And perhaps someday we will be able to safely rejuvenate the thymus, or maintain its health through one’s life, and use the thymus health score to monitor. NB: I wrote this post (No A.I.) A Quick Poll Loading... ********************************************************************* Thanks to Ground Truths subscribers (now > 200,000) from every US state and 212 countries. Your subscription to these free essays and podcasts makes my work in putting them together worthwhile. Please join! If you found this interesting PLEASE share it! Share Ground Truths Paid subscriptions are voluntary and all proceeds from them go to support Scripps Research. They do allow for posting comments and questions, which I do my best to respond to. Please don’t hesitate to post comments and give me feedback. Let me know topics that you would like to see covered. Leave a comment Many thanks to those who have contributed—they have greatly helped fund our summer internship programs for the past two years. It enabled us to accept and support 47 summer interns in 2025! We aim to accept even more of the several thousand who will apply for summer 2026.
Scientists create cartilage scaffold that helps the body regrow bone
Researchers in Sweden have engineered a cell-free cartilage scaffold that can guide the body to rebuild damaged bone. By removing the cells but preserving the structure and natural growth signals, the material acts as a blueprint for the body’s own repair process. In animal studies, it helped regenerate bone without triggering strong immune reactions. The team now plans to scale up production and begin testing the approach in humans.
Bloom and bust: can Sarah Raven regrow her garden business?
The plantswoman who single-handedly brought dahlias back into fashion and nurtured the UK through Covid had become a perennial in the horticultural firmament. Then it all went wrong
Ancient Chinese medicine may hold the key to hair regrowth
A centuries-old Chinese medicinal root is getting new scientific attention as a potential game-changer for common hair loss. Polygonum multiflorum, long believed to restore dark, healthy hair, appears to work on multiple fronts at once—blocking hair-shrinking hormones, protecting follicles from damage, activating natural regrowth signals, and boosting blood flow to the scalp.
Scientists Found a Way to Regrow Cartilage Without Using Stem Cells
Scientists reversed joint damage in mice by reprogramming aging cartilage cells.
In downtown Wilmington, Live Oak shutting down inclusive small business center
Live Oak Bank is turning Channel off. Described by Live Oak as an inclusive small business center, Channel opened in November 2021 to serve as a free resource for small business owners, helping numerous minority-owned and other small businesses from its headquarters downtown at 106 Market St. "After careful consideration, we’ve decided to bring Channel ... to a close at the end of this month. Live Oak determined that the needs of Wilmington’s small business community have evolved. Since Channel opened, the local small business ecosystem has grown significantly, with many strong organizations now offering education, technical assistance and community programming for entrepreneurs," stated Claire Parker, managing director of corporate communications for Live Oak Bank, in an email Monday. "With those resources firmly in place, Live Oak is refocusing on what we do best – providing banking and financing solutions that help small businesses grow and thrive." Channel's demise also resulted in the elimination of two positions – those of Channel's director, Chakema Clinton-Quintana, and Atiba Johnson, the certified professional business advisor (CPBA) at Channel. On Monday, Clinton-Quintana, who was elected to the Wilmington City Council in November, said of her immediate plans after Channel: "I will continue my work serving the public while I look for other full-time opportunities." She said Channel "served over 1,000 small business owners in the greater Wilmington area, as well as some of the surrounding areas, such as Brunswick and Pender. A lot of folks had reached out to us needing those resources because they were free, and we were able to assist them in that capacity." Johnson said he will be devoting his time to the Wilmington Minority Chamber of Commerce, which is not affiliated with the Greater Wilmington Chamber of Commerce. The minority chamber is celebrating its launch from 5 to 8 p.m. Tuesday at the Wilmington Sportsman Club, 1111 Castle St., Wilmington. Johnson, the founder and executive director of the new chamber, said about 50 businesses are on board to join the Wilmington Minority Chamber of Commerce. According to a news release, the new chamber "was established to foster growth, networking, and advocacy for underrepresented business owners. By providing essential resources and community engagement, the chamber aims to build a more inclusive and prosperous local economy." Johnson said the creation of the new chamber is in response to "lapses in funding, education, advocacy for minority businesses...Some of the things that are going on now just don't reach all the way down to those businesses." For Lynne Jones, owner of LJ Design Studio LLC, the loss of Channel also means a reduction in income. She had contracted with Channel to run the center's social media and to provide some marketing for small business owners. "It's pretty disappointing to hear that it is closing...it was a place to connect with other small business owners and collaborate. It was like a family for those of us who were there. If you had issues or things that you needed to talk through concerning your business, there was always someone there that you could sit down with and talk things through, recalibrate, and they set you off on your way to make that pivot and move in a different direction," Jones said Monday. She said she worked with many Channel participants creating their websites and will miss seeing the joy on their faces when those websites were up and running. Dawn McDowell, owner of Creatively Covered Co. LLC, credits Channel with helping her business grow and regrow after her social media pages were hacked and shut down in 2023. "Channel was a great resource for small businesses, for women-owned businesses, for minority-owned businesses; they provided a lot of assistance, especially when you needed it," McDowell said. "If it wasn't for Channel, I don't know if I'd be where I am now, in my business, and regrowing my business and even finding out about some of the certifications and things that were out there for small businesses that I just didn't know about ... because there was no one really sharing that information for small businesses, for minority- and women-owned businesses in particular." Parker said shutting down Channel was not part of an overall cost-cutting plan. She stated in the email, "Live Oak’s commitment to Wilmington remains strong. We are continuing to support entrepreneurs by focusing our efforts where we deliver the greatest value – through specialized banking and financing solutions aligned with our mission to be America’s small business bank." As for Channel's downtown office, Live Oak had leased the 5,000-square-foot space above Seabird restaurant in 2021. The bank’s lease for the office is up in March, Parker said.
Scientists found the soil secret that doubles forest regrowth
New research shows tropical forests can recover twice as fast after deforestation when their soils contain enough nitrogen. Scientists followed forest regrowth across Central America for decades and found that nitrogen plays a decisive role in how quickly trees return. Faster regrowth also means more carbon captured from the atmosphere. The study points to smarter reforestation strategies that work with nature rather than relying on fertilizers.
Scientists uncover the hidden survival trick that lets cancer bounce back
Scientists discovered that certain cancer cells use a low-level activation of a DNA-dismantling enzyme—normally seen in cell death—to survive treatment. Instead of dying, these “persister cells” leverage this sublethal signal to regrow. Because the mechanism is non-genetic, it appears much earlier than typical resistance mutations. Targeting this enzyme could help stop tumors from returning.
From Barton to Breakthrough Science
Dr. Taylor Medlock-Lanier, Class of 2020, has spent the last five years in her lab at the University of Georgia surrounded by containers of planarians—tiny flatworms with an extraordinary superpower. Cut one in half, and within a week, it will regrow its missing parts, including its entire brain. She’s been asking these tiny creatures a