Aging is a tale written by the cells in our bodies, although some cell types play a bigger role than others. At the crux of this story is an intriguing protagonist: the stem cell. These master builders, which can differentiate into any cell type, thereby helping to replace diseased or worn-out tissues, are essential for tissue repair and in maintaining health into old age. But as we get older, the capabilities of stem cells gradually diminish, which is known as stem cell exhaustion and is a key facet of aging itself. Stem cell exhaustion plays a role in a large number of age-related diseases, meaning that it could be a crucial research target in developing new treatments and techniques to help us age well. A Research Topic in the open-access journal Frontiers in Aging has been curated by Dr. Sarallah Rezazadeh of the Icahn School of Medicine at Mount Sinai and Professor Georgina May Ellison-Hughes of King’s College London. The Topic collects groundbreaking studies into stem cell exhaustion under one open-access roof, exploring the detailed mechanisms underlying the phenomenon and establishing the field in a wider context to identify promising therapeutic approaches for those later in life.

A future where injured or diseased organs can be removed and replaced with new lab-printed tissues that are customized specifically for each patient is not as far away as you might think. These functional and living tissues could grow naturally within the body, and repair and sustain themselves over time. While these concepts were once in the realm of science fiction, advances in bioprinting, which is a form of 3D printing using biological “inks” (known as bioinks) loaded with living cells, are bringing them closer to reality. Among the researchers advancing this field is Dr. Mingjun Xie of Zhejiang University, China, and colleagues, who are performing work that addresses a significant challenge in bioprinting. This involves creating large portions of tissues that have a functional vasculature, thereby mimicking the complexity of native tissues and organs.

In their ongoing quest to improve diabetes management, researchers are searching for new insights into the mechanisms through which the body manages blood sugar levels. Prof. Eugenio Cersosimo and colleagues at the University of Texas Health Science Center recently reported a breakthrough that could change how we understand glucose control and increase our ability to manage type 2 diabetes. Their study examines two medications, dapagliflozin, an SGLT-2 inhibitor, and exenatide, a GLP-1 receptor agonist, and how they can work together to control blood sugar levels by exploiting a previously unknown kidney-to-liver signalling pathway. Their findings have unravelled some important underlying mechanisms that provide strong support for the cardio-renal protective effects reported in many large clinical trials with the use of SGLT-2 inhibitors in patients with type 2 diabetes. The demonstration that the kidney plays a central role in glucose regulation during exposure to SGLT-2 inhibitors represents a major advance in our understanding of diabetes treatment and the prevention of severe cardiovascular and renal complications.

Researchers have made a significant advancement in understanding an important component of the nervous system: the neuromuscular junction, a crucial connection between nerves and muscles. A recent study performed by Charles Frison-Roche of the Center of Research in Myology in the Sorbonne University, Paris, and colleagues, reveals the role of proteins known as Muscleblind-like proteins, or MBNL proteins for short, which help to regulate motor coordination by helping to maintain neuromuscular junction stability. This discovery is potentially very useful, as loss-of-function of MBNL proteins is a hallmark of a genetic condition called Myotonic Dystrophy type 1 (or DM1 for short). DM1 disrupts muscle control, leading to muscle weakness, problems with balance, and other symptoms that can get progressively worse over time. MBNL proteins, and their role in the neuromuscular junction, may represent new treatment targets in DM1.

Data involving angles can be found across a diverse array of scientific fields, but so far, the mathematical tools used to study them have often proved insufficient to detect the complex relationships between different angles within large datasets. Through its research, a team consisting of Professor Christophe Ley and Sophia Loizidou from the University of Luxembourg, Professor Shogo Kato from the Institute of Statistical Mathematics in Tokyo, and Professor Kanti Mardia from the University of Leeds, has developed a new model which overcomes many of these challenges: allowing the researchers to study relationships between three angles at once, as well as mixtures of angles and classical measurements on the line.

Learning a new language as an adult is challenging, especially when the new language has features that differ significantly from one's native tongue. This phenomenon is key to a new study led by Professor Shanshan Yan at Peking University, which examines how language learning is affected when learners encounter features in their second language that are similar to those in their first language.

Liver disease is a significant health challenge globally. It can often progress unnoticed for years until it becomes life-threatening. Cirrhosis is the final stage of chronic liver diseases, and it can be caused by conditions such as viral hepatitis, excessive alcohol consumption, or metabolic-associated steatotic liver disease, which is linked to conditions such as obesity or diabetes. Once cirrhosis has set in, the tissue in the liver becomes permanently scarred, reducing its function, and this can progress to liver failure or liver cancer. Often, these conditions are not diagnosed in sufficient time for effective treatment. Happily, a new risk assessment tool called the LiverRisk score, developed by the LiverScreen Consortium, could pave the way for early liver disease diagnosis, potentially allowing clinicians to intervene before irreversible liver damage occurs. The LiverRisk score helps to identify those who are at risk of severe liver complications in the future. The diagnostic tool is designed to be easy to use, and is based on clinical markers that are widely available from routine blood tests.

For decades, works of science fiction have explored how the universe’s most fundamental speed limit could be broken by warping the fabric of spacetime. Through his experiments, Dr. Chance Glenn, founder of Morningbird Space Corporation, believes he may have discovered how spacetime can be distorted by extreme electric fields, which can be easily created in the lab. If his theory is correct, it would mean that the concept of ‘warp drives’ which allow us to travel at faster than the speed of light could be more feasible than we once thought.

The transition from the Middle to Upper Paleolithic in Europe marks a pivotal period in human evolution, with the replacement of Neanderthals by anatomically modern humans. A new study by Nicolas Teyssandier, Director of Research at the French National Center for Scientific Research (CNRS) and vice director of the TRACES laboratory at the Toulouse Jean Jaurès University examines the archaeological evidence for this transition and attempts to reconcile it with recent discoveries, shedding new light on this complex period of cultural and biological change.

Americans generally celebrate the abstract principle of diversity but does this translate into the policies that they support and the friendships that they form? A new study from Prof. Neeraj Rajasekar of the University of Illinois Springfield, Prof. Evan Stewart of the University of Massachusetts and Prof. Douglas Hartmann of the University of Minnesota, examines this. Rajasekar and colleagues find inconsistencies between Americans' support for diversity in principle versus their attitudes in their day-to-day lives. The findings reveal widespread gaps that exist across demographic groups, with implications for understanding public opinion and advancing diversity efforts in the United States.