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E-cigarettes may not reduce disease risk

A new research has revealed that nicotine, which is the major addictive substance in cigarette smoke, contributes to smokers’ higher risk of developing atherosclerosis, the primary cause of heart attacks.

Chi-Ming Hai from Brown University said the findings suggested that e-cigarettes, the battery-powered devices that deliver nicotine in steam without the carcinogenic agents of tobacco smoke, may not significantly reduce smokers’ risk for heart disease.

Dr. Hai’s research on human and rat vascular smooth muscle cells provides evidence of a link between nicotine and atherosclerosis.

In Dr. Hai’s experiments, nicotine appeared to drive the formation of a kind of cellular drill called podosome rosettes, which are members of the invadosome family, consisting of invadopodia, podosomes and podosome rosettes.

These specialized cell surface assemblies degrade and penetrate the tissue during cell invasion.

Targeting glucose can fight seasonal flu

A new research has revealed that reducing glucose metabolism dials down influenza viral infection in laboratory cell cultures, providing an entirely new approach for combating seasonal flu.

While annual flu shots are based on the U.S. Centers for Disease Control (CDC)’s predictions of the viruses that will be in widest circulation each flu season, the new approach targets one metabolic requirement of all influenza viruses: glucose.

Reducing viruses’ glucose supply weakens the microbes’ ability to infect host cells, said Amy Adamson, Ph.D., and Hinissan Pascaline Kohio of the University of North Carolina, Greensboro.

To infect cells, the influenza virus is dependent upon the actions of the cell’s own proteins, and so another strategy for slowing viral infection would be to target essential viral needs, for example, their dependence on cellular glucose. Dr. Adamson and Kohio showed that influenza A infection can be controlled in laboratory cultures of mammalian cells by altering glucose metabolism.

When the influenza virus initially infects a cell, and the virus is confined in an endocytic vesicle, the viral proteins HA and M2 use the acidic environment inside the vesicle to fuse the viral lipid envelope with that of the vesicle, and then release the viral genome into the cytosol.

The acidic pH that mediates these important viral process is established and maintained by the cell’s vacuolar-type H+ ATPase (V-ATPase) proton pump. The researchers found that this dependence could be used to manipulate the infection’s success. Dr. Adamson and Kohio boosted glucose concentrations in the laboratory cell cultures, and influenza infection rate concomitantly increased. Treating the viral cells with a chemical that inhibits glucose metabolism significantly decreased viral replication in the lab cultures.

Regular exercise protects against age-related problems

A new study has suggested that regular exercise in middle age is a protective factor against sarcopenia and effective in maintaining muscle strength and physical performance.

Sarcopenia is a disease associated with the ageing process, resulting in loss of skeletal muscle mass and muscle strength and function in the elderly. The multiple adverse health outcomes include physical disability, poor quality of life and premature death.

The cross-sectional study by investigators from Tokyo University assessed the prevalence of sarcopenia and its association with physical performance in 1000 elderly Japanese participants in the Research on Osteoarthritis or Osteoporosis Against Disability (ROAD) Study.

Handgrip strength, gait speed, and skeletal muscle mass were measured and other information collected, including exercise habits in middle age.

The prevalence of sarcopenia was 13.8 percent in men and 12.4 percent in women, and tended to be significantly higher with increasing age in both sexes.

Analysis showed that exercise habit in middle age was associated with low prevalence of sarcopenia in older age and was significantly associated with grip strength, gait speed, and one-leg standing time after adjusting for age, sex and BMI.

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