ROS production, intracellular HSP70 levels and their relationship in human neutrophils: effects of age

Abstract

ROS production and intracellular HSP70 levels were measured in human neutrophils for three age groups: young (20-59 years), elders (60-89 years) and nonagenarians (90 years and older). Elders showed higher levels of spontaneous intracellular ROS content compared with young and nonagenarian groups, which had similar intracellular ROS levels. Zymosan-induced (non-spontaneous) extracellular ROS levels were also similar for young and nonagenarians but were lower in elders. However, spontaneous extracellular ROS production increased continuously with age. Correlation analysis revealed positive relationships between HSP70 levels and zymosan-stimulated ROS production in the elder group. This was consistent with a promoting role for HSP70 in ROS-associated neutrophils response to pathogens. No positive correlation between ROS production and intracellular HSP70 levels was found for groups of young people and nonagenarians. In contrast, significant negative correlations of some ROS and HSP70 characteriscics were found for neutrophils from young people and nonagenarians. The observed difference in ROS and HSP70 correlations in elders and nonagenarians might be associated with an increased risk of mortality in older individuals less than 90 years old.

Mitochondrial activity and dynamics changes regarding metabolism in ageing and obesity

“…In human muscle, ageing is accompanied by a higher need of mitochondria to maintain the same respiratory capacity as in young people indicating decay in mitochondrial efficiency (Larsen et al, 2012). Although the role of mitochondria as the major source of intracellular ROS production in ageing has been questioned during the last years , most data suggest that there is an increase in oxidative damage in the elderly affecting senescence (Lu and Finkel, 2008), fertility declining (Benkhalifa et al, 2014), skin ageing (Kammeyer and Luiten, 2015), neutrophils' activity (Kovalenko et al, 2014) or skeletal muscle (McDonagh, 2016).…”

Expression of cellular protective proteins SIRT1, HSP70 and SOD2 correlates with age and is significantly higher in NK cells of the oldest seniors

“…There are only few studies concerning this issue and they refer to monocytes [41], lymphocytes [23, 41] and granulocytes [28]. There was observed age-related raise in the basal level of HSP70 in monocytes and lymphocytes [41].…”

“…Previous study, however, showed a significant age-related decrease in HSP70 levels in lymphocytes [23]. Studies performed on neutrophils did not expose any significant age-dependent changes in HSP70 basal content in the cells [28]. Since NK cells are associated with the process of healthy ageing, the preservation of NK cell function until very advanced age may contribute to longevity [12, 18, 31].…”

Physiological regulation of the heat shock response by glutamine: implications for chronic low-grade inflammatory diseases in age-related conditions

“…Moreover, it is important to highlight that in neutrophils, for example, ROS are essential for pathogen destruction through phagocytosis and for robust inflammatory responses [141]. Interestingly, in the elderly (60-89 years), a positive correlation has been found between iHSP70 and spontaneous ROS production by neutrophils, but the same correlation has not been confirmed in nonagenarians (>90 years) [142]. The lack of a positive correlation between neutrophil HSP70 levels and ROS in the latter group might be associated with the longer lifespan of these specific people.…”