London’s air pollution problem means that for the city’s older adults exercise counts for nothing

A study has concluded that even short-term exposure to air pollution in built up areas like London’s Oxford Street can negate the beneficial health effects of exercise in older adults.

The research by Imperial College London and Duke University, and published in The Lancet, adds to the growing body of evidence showing the negative impacts of urban air pollution on cardiovascular and respiratory health, and highlights the need for stricter air quality limits and greater access to green spaces.

“It’s possible that studies such as this could support new air quality limits, it shows that we can’t really tolerate the levels of air pollution that we currently find on our busy streets,” said senior author Fan Chung, Professor of Respiratory Medicine and Head of Experimental Studies Medicine at National Heart & Lung Institute at Imperial College London.

Image courtesy of Ron Porter

For the study, funded by the British Heart Foundation, researchers recruited 119 volunteers, aged over 60, who were either healthy, had stable Chronic Obstructive Pulmonary Disease (COPD) or had stable heart disease.

The volunteers were then split into two groups. One of the groups walked for two hours in a relatively serene part of Hyde Park, while the second group walked along a busy stretch of Oxford Street – which has regularly breached air quality limits set by the World Health Organization.

Physical measurements were taken before and after the walks to show the effects of the exercise on cardiovascular health, including measurements of lung volume exhaled, blood pressure and the degree to which the blood vessels could expand.

Environmental measurements were also collected, to track pollution levels and volunteers’ exposure.

Image courtesy of David Holt

Analysis revealed that all participants benefitted from a stroll in the park, with lung capacity improving within the first hour and a significant lasting increase for more than 24 hours in many cases.

By comparison, a walk along Oxford Street led to only a small increase in lung capacity in participants, far lower than recorded in the park.

Blood flow also increased after exercise, with decreases in blood pressure and an increase in heart rate. Arteries became less stiff in those walking in Hyde Park with a maximum change from baseline of more than 24% in healthy and COPD volunteers, and more than 19% in heart disease patients.

This effect was drastically reduced when walking along Oxford Street, however, with a maximum change in arterial stiffness of just 4.6% for healthy volunteers, 16% for those with COPD and 8.6% for heart disease.

“These findings are important as for many people, such as the elderly or those with chronic disease, very often the only exercise they can do is to walk,” said Chung.

“Our research suggests that we might advise older adults to walk in green spaces, away from built-up areas and pollution from traffic.”

Cloning did not cause Dolly the sheep to get arthritis, scientists confirm

A new study has dismissed concerns that cloning caused early-onset osteoarthritis (OA) in Dolly the sheep.

Scientists from the University of Nottingham and the University of Glasgow have published a radiographic assessment of the skeletons of Dolly, Bonnie (Dolly’s naturally conceived daughter) and Megan and Morag (the first two animals to be cloned from differentiated cells) that shows no abnormal OA.

The study follows the team’s research last year into the Nottingham ‘Dollies’, a quartet of sheep cloned in 2007 from the same line as Dolly, that showed the cloned sheep to age the same as naturally born sheep.

According to their assessment of the skeletons, the OA observed within the skeletons is similar to that naturally conceived sheep and Nottingham’s healthy aged clones.

Professor Sandra Corr, Professor of Small Animal Orthopaedic Surgery who has since moved to Glasgow University, said: “We found that the prevalence and distribution of radiographic-OA was similar to that observed in naturally conceived sheep, and our healthy aged cloned sheep.

As a result we conclude that the original concerns that cloning had caused early-onset OA in Dolly were unfounded.”

The new study arose after the findings regarding the Nottingham ‘Dollies’.

Derived from the same cell line that produced Dolly, the four sheep originated from Professor Keith Campbell’s attempts to improve the efficiency of the cloning method somatic-cell nuclear transfer (SCNT) and were left as his legacy to the University of Nottingham.

Studying the ‘Dollies’, Kevin Sinclair, Professor of Developmental Biology, in the School of Biosciences, along with Corr and David Gardner, Professor of Physiology at Nottingham’s School of Veterinary Medicine and Science, found radiographic evidence of only mild or, in one case, moderate OA.

Images courtesy of the University of Nottingham.

Given that the ‘Dollies’ had aged so apparently normal, the team felt that their findings stood in too stark a contrast to reports that cloning had caused Dolly to suffer from early-onset OA. First emerging in 2003, reports stated that at the age of 5½ Dolly was suffering from OA.

However, the only formal record of any OA in Dolly was a brief mention in a conference abstract, stating that Dolly had OA of the left knee.

In the absence of the original records however, the team were compelled to travel to Edinburgh, where the skeletons are stored in the collections of National Museums Scotland.

With special permission from Dr Andrew Kitchener, Principal Curator of Vertebrates at National Museums Scotland, the team then performed the X-rays on Dolly and her contemporary clones to reassess that 2003 diagnosis.

Sinclair said: “Our findings of last year appeared to be at odds with original concerns surrounding the nature and extent of osteoarthritis in Dolly – who was perceived to have aged prematurely. Yet no formal, comprehensive assessment of osteoarthritis in Dolly was ever undertaken. We therefore felt it necessary to set the record straight.”