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Evening exercise benefits elderly hypertensives

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Evening exercise benefits elderly hypertensives

A study conducted at the University of São Paulo with 23 volunteers found that aerobic exercise performed in the evening benefits elderly hypertensives more than morning exercise.

Aerobic training is known to regulate blood pressure more effectively when practiced in the evening than in the morning.

Researchers who conducted a study of elderly patients at the University of São Paulo’s School of Physical Education and Sports (EEFE-USP) in Brazil concluded that evening exercise is better for blood pressure regulation thanks to improved cardiovascular control by the autonomic nervous system via a mechanism known as baroreflex sensitivity.

Leandro Campos de Brito, first author of the article, commented: “There are multiple mechanisms to regulate blood pressure, and although morning training was beneficial, only evening training improved short-term control of blood pressure by enhancing baroreflex sensitivity.

“This is important because baroreflex control has a positive effect on blood pressure regulation, and there aren’t any medications to modulate the mechanism.”

In the study, 23 elderly patients diagnosed and treated for hypertension were randomly allocated into two groups: morning training and evening training. Both groups trained for ten weeks on a stationary bicycle at moderate intensity, with three 45-minute sessions per week.

Key cardiovascular parameters were analysed, such as systolic and diastolic blood pressure, and heart rate after ten minutes’ rest. The data was collected before and at least three days after the volunteers completed the ten weeks of training.

The researchers also monitored mechanisms pertaining to the autonomic nervous system, which controls breathing, heart rate, blood pressure, digestion, and other involuntary bodily functions, such as muscle sympathetic nerve activity, which regulates peripheral blood flow via contraction and relaxation of blood vessels in muscle tissue, and sympathetic baroreflex sensitivity, assessing control of blood pressure via alterations to muscle sympathetic nerve activity.

In the evening training group, all four parameters analysed were found to improve: systolic and diastolic blood pressure, sympathetic baroreflex sensitivity, and muscle sympathetic nerve activity. In the morning training group, no improvements were detected in muscle sympathetic nerve activity, systolic blood pressure or sympathetic baroreflex sensitivity.

“Evening training was more effective in terms of improving cardiovascular autonomic regulation and lowering blood pressure. This can be partly explained as due to an improvement in baroreflex sensitivity and a reduction of muscle sympathetic nerve activity, which increased in the evening. For now, all we know is that baroreflex control is the decisive factor, from the cardiovascular standpoint at least, to make evening training more beneficial than morning training, since it induces the other benefits analysed. However, much remains to be done in this regard in order to obtain a better understanding of the mechanisms involved,” said Brito, who is currently a professor at Oregon Health & Science University’s Oregon Institute of Occupational Health Sciences in the United States, and continues to investigate the topic via circadian rhythm studies.

Baroreflex sensitivity regulates each heartbeat interval and controls autonomic activity throughout the organism.

“It’s a mechanism that involves sensitive fibres and deformations in the walls of arteries in specific places, such as the aortic arch and carotid body. When blood pressure falls, this region warns the brain region that controls the autonomic nervous system, which in turn signals the heart to beat faster and tells the arteries to contract more strongly. If blood pressure rises, it warns the heart to beat more slowly and tells the arteries to contract less. In other words, it modulates arterial pressure beat by beat,” Brito explained.

In previous studies, the EEFE-USP research group showed that evening aerobic training reduced blood pressure more effectively than morning training in hypertensive men (read more at: agencia.fapesp.br/34194), and that the more effective response to evening training in terms of blood pressure control was accompanied by a greater reduction in systemic vascular resistance and systolic pressure variability (read more at: agencia.fapesp.br/37432).

“Replication of the results obtained in previous studies and in different groups of hypertensive patients, associated with the use of more precise techniques to evaluate the main outcomes, has strengthened our conclusion that aerobic exercise performed in the evening is more beneficial to the autonomic nervous system in patients with hypertension. This can be especially important for those with resistance to treatment with medication,” Brito said.

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Mole rat gene extends mouse lifespan

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A mole rat gene inserted into mice extended lifespan and improved health, findings that may point to new ways of supporting healthier ageing.

The gene increased production of a large form of hyaluronan, a naturally occurring gel-like substance between cells that helps tissue repair and cell-to-cell communication.

Mice carrying the naked mole rat version of the gene showed an approximately 4.4 per cent increase in median lifespan, alongside multiple markers of healthier ageing.

Naked mole rats have become a focus of ageing research because they combine an exceptional lifespan with unusual resistance to many age-linked diseases, including cancer.

Researchers at the University of Rochester traced part of that resilience to hyaluronan.

The molecule’s effects depend on its size: large forms are often linked to anti-inflammatory and tissue-protective behaviour, while smaller fragments can act as danger signals that increase inflammation.

Vera Gorbunova, professor of biology and medicine at the University of Rochester in the US, said: “Our study provides a proof of principle that unique longevity mechanisms that evolved in long-lived mammalian species can be exported to improve the lifespans of other mammals.”

The engineered mice were better protected against both spontaneous tumours and chemically induced skin cancer.

They also showed reduced inflammation across tissues, a notable finding because persistent low-grade inflammation, sometimes called inflammaging, is widely seen as one of the central drivers of age-related decline.

The research also linked the large form of hyaluronan to age-related gut health. As animals age, the gut barrier can become leakier, allowing inflammatory triggers to pass into the bloodstream.

The engineered mice showed protection against this deterioration.

Follow-up work found abundant high-molecular-mass hyaluronan across multiple species of subterranean mammals, often absent in closely related above-ground species, suggesting it may be part of a broader evolutionary toolkit for surviving long lives under harsh conditions.

The team said gene transfer is not the end goal. Gorbunova said: “It took us 10 years from the discovery of HMW-HA in the naked mole rat to showing that HMW-HA improves health in mice.”

“Our next goal is to transfer this benefit to humans.”

Two practical routes are being pursued: increasing production of the large form of hyaluronan, or slowing its breakdown.

Andrei Seluanov, who co-leads the research, said: “We already have identified molecules that slow down hyaluronan degradation and are testing them in pre-clinical trials.”

One candidate identified through screening is delphinidin, a plant pigment found in various fruits and vegetables.

In tests, it was found to increase levels of the large form of hyaluronan in cells and mouse tissues, reduce migration and invasion in multiple cancer cell lines, and suppress melanoma metastasis in mice.

However, the researchers acknowledged the approach has limits. A later study found that mice expressing the naked mole rat gene showed improvements in several late-life health measures but did not show protection from age-related hearing loss, suggesting some organs may be less reachable by this pathway than others.

The Rochester team said turning these findings into human therapies will likely depend on precision: maintaining the right molecular form of hyaluronan, targeting the right balance of production versus breakdown, and monitoring carefully for trade-offs as different tissues respond in different ways.

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AI can predict Alzheimer’s with almost 93% accuracy, researchers say

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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.”

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Vision implant firm raises US$230m

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A vision implant firm has raised US$230m as it seeks approval in Europe and the US for a device that restored sight in a small clinical trial.

The Alameda, California-based startup said the funding would support commercialisation of its Prima device.

It said an upcoming launch is planned in Europe and that it would become the first brain computer interface company to have a vision restoration device on the market.

A clinical trial in Europe found the small implant could work as artificial photoreceptors in the retina to restore functional central vision.

The implant is placed under the retina to replace the function of light-sensitive cells lost to disease. A special pair of glasses with an embedded camera and infrared projector sends light signals to the implant.

The study assessed the system in people with advanced dry age-related macular degeneration.

Of the 38 patients who received an implant, 32 were assessed at 12 months. Results showed the device led to a clinically meaningful improvement in visual acuity in 26 people.

The patients were able to read letters, numbers and words, according to the company.

Science Corporation said it has submitted a CE mark application to the European Union and applied to the US Food and Drug Administration for regulatory approval.

Darius Shahida, chief strategy officer, said: “Our imperative is to become the first BCI company to scale and achieve profitability.”

Founded in 2021, the company has now raised about US$490m in total. It said it is expanding its clinical trial programme to include other retinal diseases, such as Stargardt disease and retinitis pigmentosa.

The Series C round included existing investors Khosla Ventures, Lightspeed Venture Partners, Y Combinator, IQT and Quiet Capital.

Science Corporation said demand for the round exceeded its capital needs, with funds also earmarked for expanding research, manufacturing infrastructure and operations.

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