News
Ageing fight revealed in new ‘muscle map’

The first comprehensive cell atlas of ageing human muscle reveals the intricate genetic and cellular processes behind muscle deterioration and mechanisms to counteract it.
How muscle changes with ageing, and tries to fight its effects, is now better understood at the cellular and molecular level with the first comprehensive atlas of ageing muscles in humans.
Researchers from the Wellcome Sanger Institute and their collaborators at Sun Yat-sen University, China applied single-cell technologies and advanced imaging to analyse human skeletal muscle samples from 17 individuals across the adult lifespan. By comparing the results, they shed new light on the many complex processes underlying age-related muscle changes.
The atlas uncovers new cell populations that may explain why some muscle fibres age faster than others. It also identifies compensatory mechanisms the muscles employ to combat ageing.
The findings offer avenues for future therapies and interventions to improve muscle health and quality of life as we age.
This study is part of the international Human Cell Atlas initiative to map every cell type in the human body, to transform understanding of health and disease.
As we age, our muscles progressively weaken. This can affect our ability to perform everyday activities like standing up and walking. For some people, muscle loss worsens, leading to falls, immobility, a loss of autonomy and a condition called sarcopenia. The reasons why our muscles weaken over time have remained poorly understood.
In this new study, scientists from the Wellcome Sanger Institute and Sun Yat-sen University, China used both single-cell and single-nucleus sequencing techniques along with advanced imaging to analyse human muscle samples from 17 individuals aged 20 to 75.
The team discovered that genes controlling ribosomes, responsible for producing proteins, were less active in muscle stem cells from aged samples. This impairs the cells’ ability to repair and regenerate muscle fibres as we age. Further, non-muscle cell populations within these skeletal muscle samples produced more of a pro-inflammatory molecule called CCL2, attracting immune cells to the muscle and exacerbating age-related muscle deterioration.
Age-related loss of a specific fast-twitch muscle fibre subtype, key for explosive muscle performance, was also observed. However, they discovered for the first time several compensatory mechanisms from the muscles appearing to make up for the loss. These included a shift in slow-twitch muscle fibres to express genes characteristic of the lost fast-twitch subtype, and increased regeneration of remaining fast-twitch fibre subtypes.
The team also identified specialised nuclei populations within the muscle fibres that help rebuild the connections between nerves and muscles that decline with age. Knockout experiments in lab-grown human muscle cells by the team confirmed the importance of these nuclei in maintaining muscle function.
Veronika Kedlian, first author of the study from the Wellcome Sanger Institute, said: “Our unbiased, multifaceted approach to studying muscle ageing, combining different types of sequencing, imaging and investigation reveals previously unknown cellular mechanisms of ageing and highlights areas for further study.”
Professor Hongbo Zhang, senior author of the study from Sun Yat-sen University, Guangzhou, China, said: “In China, the UK and other countries, we have ageing populations, but our understanding of the ageing process itself is limited. We now have a detailed view into how muscles strive to maintain function for as long as possible, despite the effects of ageing.”
Dr Sarah Teichmann, senior author of the study from the Wellcome Sanger Institute, and co-founder of the Human Cell Atlas, said: “Through the Human Cell Atlas, we are learning about the body in unprecedented detail, from the earliest stages of human development through to old age.With these new insights into healthy skeletal muscle ageing, researchers all over the world can now explore ways to combat inflammation, boost muscle regeneration, preserve nerve connectivity, and more. Discoveries from research like this have huge potential for developing therapeutic strategies that promote healthier ageing for future generations.”
News
Mole rat gene extends mouse lifespan
News
AI can predict Alzheimer’s with almost 93% accuracy, researchers say

Alzheimer’s AI can predict the disease with nearly 93 per cent accuracy using more than 800 brain scans, researchers say.
The system identified anatomical changes in the brain linked to the onset of the most common form of dementia, a condition that gradually damages memory and thinking.
The findings build on years of research suggesting AI could help spot early Alzheimer’s risk, predict disease and identify patients whose condition has not yet been diagnosed.
Benjamin Nephew, an assistant research professor at the Worcester Polytechnic Institute in Massachusetts, said: “Early diagnosis of Alzheimer’s disease can be difficult because symptoms can be mistaken for normal ageing.
“We found that machine-learning technologies, however, can analyse large amounts of data from scans to identify subtle changes and accurately predict Alzheimer’s disease and related cognitive states.”
The study used MRI scans, a type of detailed brain imaging, from 344 people aged 69 to 84.
The dataset included 281 scans showing normal mental function, 332 with mild cognitive impairment, an early stage of memory and thinking decline, and 202 with Alzheimer’s.
The scans covered 95 of the brain’s nearly 200 distinct regions and used an AI algorithm to predict patients’ health.
Being able to use AI to help diagnose Alzheimer’s earlier could give patients and doctors crucial time to prepare and potentially slow the progression of the disease.
The analysis showed that one of the top predictive factors was brain volume loss, or shrinkage, in the hippocampus, which helps form memories, the amygdala, which processes fear, and the entorhinal cortex, which helps provide a sense of time.
This pattern held across age and sex, with both men and women aged 69 to 76 showing volume loss in the right part of the hippocampus, suggesting it may be an important area for early diagnosis, the researchers noted.
However, the research also found that the way brain regions shrink differs by sex.
In females, volume loss occurred in the brain’s left middle temporal cortex, which is involved in language and visual perception. In males, it was mainly seen in the right entorhinal cortex
The researchers believe this could be linked to changes in sex hormones, including the loss of oestrogen in women and testosterone in men.
These conclusions could help improve methods of diagnosis and treatment going forward, Nephew said.
More than 7.2m Americans are living with Alzheimer’s, according to the Alzheimer’s Association.
More research is being done to reveal other impacting factors.
Nephew said: “The critical challenge in this research is to build a generalisable machine-learning model that captures the difference between healthy brains and brains from people with mild cognitive impairment or Alzheimer’s disease.”
News
Vision implant firm raises US$230m
News2 weeks agoInterview: The US company appealing Europe’s rejection of daily Alzheimer’s pill
News4 weeks agoLongevity startup Biopeak raises US$2.7m
News4 weeks agoBryan Johnson launches US$1m longevity programme
Markets & Industry4 weeks agoAgetech investment & innovation round-up
News2 weeks agoCentenarians’ blood reveals longevity clues
News4 weeks agoInterview: Dr Matthew Bennett on building resilience and a pain-free healthspan
Wellness4 weeks agoRe:Cognition and Cera expand Alzheimer’s clinical trials access
News4 weeks agoFrench biotech raises €12m for osteoarthritis trial

















