Page URL:

Cell ageing slowed by HRT, but only for Alzheimer's risk gene carriers

18 February 2013
Appeared in BioNews 693

Hormone replacement therapy (HRT), used to treat the symptoms of menopause, may play a role in slowing the ageing process in women who carry a certain gene variant, claim scientists. The variant in the gene ApoE4 has previously been associated with an increased risk of developing Alzheimer's disease.

'ApoE4 is contributing to ageing at the cellular level well before any outward symptoms of decline become apparent', said Professor Natalie Rasgon, who led the study at the Stanford School of Medicine. 'Yet, oestrogen appears to have a protective effect for middle-aged women who are carrying this genetic risk factor'.

The study, published in PLOS ONE, included 63 healthy post-menopausal women who had been undergoing HRT for over a year. HRT involves replacing the hormones women lose following menopause, including oestrogen. Of the group of participants, 24 carried the ApoE4 gene variant. The study lasted two years, during which time half of the group discontinued HRT and the other half continued to receive it as usual. The researchers looked at the effects of the treatment on biological ageing.

Telomere shortening can be used as read-out of biological ageing. Telomeres are segments of DNA that protect the genetic information of a cell as it divides. As telomeres become shorter each time a cell divides, they can be used to assess cell age. The participants' telomeres were measured at the beginning and end of the study by analysing blood samples. The change in telomere length indicated the amount of cell ageing that had occurred.

Post-menopausal women who carried the ApoE4 variant were six times more likely to undergo significant shortening in telomere length, suggesting 'ApoE4 carriers are at greater risk of biological ageing, which is associated with negative health outcomes', said lead study author Dr Emily Jacobs of Harvard Medical School. This effect was reduced in women who carried the ApoE4 variant but continued to receive HRT.

In contrast, women who did not carry the ApoE4 variant showed less biological ageing, as determined by a reduction in telomere length, if they stopped receiving HRT. These findings suggest that HRT may have different effects on cell ageing that are dependent on a woman's genetic make-up. 'This brings us a step closer to being able to identify which women will benefit the most from oestrogen replacement therapy', says Dr Jacobs.

'Although this small study did not investigate whether HRT could prevent Alzheimer's or measure its effects on cognition, the results could provide a useful new lead for research in this complex area', said Head of Research at Alzheimer’s Research UK, Dr Simon Ridley, to the Independent. 'Ultimately, we'd need to see large-scale, long-term trials to know whether HRT can prevent Alzheimer's, and how the effects of this therapy might differ depending on our genetic make-up'.

Accelerated biological aging evident in women with Alzheimer’s risk factor, but inhibited by hormone therapy, researchers say
Stanford School of Medicine (press release) |  13 February 2013
Accelerated Cell Aging in Female APOE-ε4 Carriers: Implications for Hormone Therapy Use
PLOS ONE |  13 February 2013
Could HRT stop dementia?
NHS Choices |  14 February 2013
HRT could help delay onset of dementia
Daily Telegraph |  13 February 2013
HRT 'protects' against rapid ageing that may be linked to Alzheimer's disease, study finds
Independent |  14 February 2013
Taking HRT may reduce the risk of Alzheimer's disease
Mail Online |  14 February 2013
28 October 2013 - by Siobhan Chan 
A DNA-based biological clock has shown that different parts of the body age at varying rates, with breast tissue and tumour cells appearing older than the rest of the body...
23 September 2013 - by Dr Jess Buxton 
A US study proclaiming the health benefits of stress management, gentle exercise and a 'plant-based' diet grabbed the attention of the world's media last week, but what was novel about the findings, and are the life-extending claims justified?...
23 September 2013 - by Dr Rachael Panizzo 
Switching to a healthier lifestyle may reverse the signs of ageing at the genetic level in men with low-risk prostate cancer, a small study has found....
8 April 2013 - by Dr Linda Wijlaars 
Three new genetic markers for Alzheimer's disease have been identified, pointing to a less well-known mechanism to explain how the disease develops...
19 November 2012 - by Helen Brooks 
A single genetic mutation increases the risk of developing Alzheimer’s disease by threefold, say scientists from two independent research groups...
15 October 2012 - by Dr Nicola Davis 
Up to three experimental drugs will be trialled to determine if they can be used to prevent the development of Alzheimer's disease...
16 July 2012 - by Dr Linda Wijlaars 
A rare genetic mutation, found in about one percent of Icelanders in a recent study, appears to protect against Alzheimer's disease and age-related cognitive decline. It is the first mutation found to act in this way and could be a target for future drug therapy...
19 July 2010 - by Chris Chatterton 
Middle-aged people without Alzheimer's disease who have a 'high risk' variant of the TOMM40 gene are more likely to have poorer memory, new research findings suggest...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.