Research suggests running may help shrink tumours

High-intensity exercise might help slow the growth of cancer cells; air quality link to stroke; and remaining sociable after retirement can lead to longer life

PUBLISHED : Monday, 22 February, 2016, 2:00am
UPDATED : Monday, 22 February, 2016, 2:00am

Running could slow cancer growth

Mice who spent their free time on a running wheel were better able to shrink tumours (a 50 per cent reduction in tumour size) compared to their less active counterparts, qaccording to a new study in the journal Cell Metabolism. Researchers found that the surge of adrenaline that comes with a high-intensity workout helped to move cancer-killing immune cells, or NK (natural killer) cells, towards lung, liver, or skin tumours implanted into the mice. When mice were depleted of NK cells, they had a normal rate of cancer growth – even with exercise and a full suite of other immune cells. Blocking the function of adrenaline also blunted the cancer-killing benefits. The researchers discovered that an immune signalling molecule called IL-6 – released from muscle tissue during exercise – was the link between adrenaline-dependent mobilisation of NK cells and tumour infiltration. “As someone working in the field of exercise and oncology, one of the main questions that cancer patients ask is: how should I exercise?” says senior study author Pernille Hojman from the University of Copenhagen. “While it has previously been difficult to advise people about the intensity at which they should exercise, this study suggests that it might be beneficial to exercise at a somewhat high intensity in order to provoke a good epinephrine surge and hence recruitment of NK cells.”


Number of strokes increase along with rise in pollution

Using data from the US and China, a new study has found that higher pollution levels are linked to a higher total number of strokes. Researchers from Drexel University in Philadelphia evaluated air quality data collected between 2010 and 2013 from 1,118 counties in 49 states in America and from 120 cities in 32 provinces in China. Across the two countries, the total number of stroke cases rose 1.19 per cent for each 10 micrograms per cubic metre of air increase of PM2.5. PM2.5 particles pose the greatest health risks due to their small size (1/30th diameter of a human hair) and are created by combustion in cars, power plants, forest fires and other things. In addition, lead study author Dr Longjian Liu, an associate professor of epidemiology and biostatistics, says researchers found a significant regional variation in PM2.5 levels that was linked to the number of stroke cases. The researchers also found that temperature had an impact on air quality and risk of stroke. “Seasonal variations in air quality can be partly attributable to climate changes,” says Liu. “In the summer, there are lots of rainy and windy days, which can help disperse air pollution. High temperatures create a critical thermal stress that may lead to an increased risk for stroke and other heat- and air quality-related illnesses and deaths.”


Socialising after retirement linked to longer life

Membership of social groups, such as book clubs or church groups, after retirement is linked to a longer life, with the impact on health and well-being similar to that of regular exercise, suggests research published in the online journal BMJ Open. Tracking the health of 424 people for six years after retirement, it was found that the more groups an individual belongs to in the first few years after stopping work, the lower their risk of death. All the participants were at least 50 years old and living in England. Membership of social groups was also associated with quality of life. Compared with those still working, every group membership lost after retirement was associated with about a 10 per cent drop in quality of life score six years later. No such patterns were seen in those still in formal employment. The researchers also separately assessed whether changes in physical activity levels affected risk of death and compared this with the magnitude of the effect of social group membership. They found that the effects of physical activity on health were comparable to those associated with maintaining old group memberships and developing new ones.