Heat shock protein 32 in human peripheral blood mononuclear cells: effect of aging and inflammation.
ABSTRACT The purpose of the present study was to assess the influence of age and acute infection on the production of Hsp32 in human peripheral blood cells, using flow cytometry. Thirty-five controls and 31 patients with acute infection participated. We found that the age and inflammatory status correlated positively with Hsp32 levels in both heat shocked (HS) and non-HS monocytes and lymphocytes. In addition, the HS response of Hsp32 was different in these peripheral blood cells; whereas HS exerted an up-regulation in the levels of Hsp32 in monocytes, a significant decrease in Hsp32 levels was noticed for lymphocytes. We found significant relationships between circulating C-reactive protein as well as interleukin-6 and the levels of Hsp32 in cells. We conclude that Hsp32 is up-regulated in the elderly as well as in individuals with inflammation, and that the HS response of Hsp32 is different in monocytes as compared to lymphocytes.
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ABSTRACT: Hsp are highly conserved cytoprotective proteins which have been repeatedly portrayed at elevated levels in various infectious diseases, and there are suggestions that the presence of infectious agents may possibly be the root cause of Hsp induction. As organisms age the vulnerability to illnesses such as infection and inflammation increases and late complications due to infectious agents are mostly observed in the older part of the population. Although it is well known that environmental conditions can modulate the susceptibility to infection, and that poor nutritional status can increase the risk of contracting infection when exposed to an infectious agent, the effects of environmental conditions and nutritional status on the heat shock response have not been investigated. Therefore, we studied the heat shock response in a special elderly population living in a remote area in Cameroon, where infection and parasitosis are endemic. Our results indicate a significant increase in Hsp70 serum levels with increasing degree of inflammation. We found negative correlations between Hsp70 levels and micronutrients including vitamin D, vitamin B12, as well as folate, which could be linked to the immune modulating effects of these vitamins.Archives of gerontology and geriatrics 02/2011; 53(3):359-63. · 1.36 Impact Factor
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ABSTRACT: Cell stress responses are ubiquitous in all organisms and are characterized by the induced synthesis of heat shock proteins (Hsp). Previous studies as well as recent reports by our group have consistently suggested that aging leads to an increase in the basal levels of Hsp70. Here we extend these studies by examining the differential Hsp70 response of peripheral blood lymphocyte (PBL) subsets. It is well established that with aging, one of the major changes in the T cell pool is an expansion of T cells with the memory phenotype as well as those deficient for the CD28 molecule. To determine if alterations in the frequency of T cell subsets might be responsible for the observations, we have carried out a more comprehensive flow cytometric analysis of the various phenotypes of PBL under unstimulated conditions. Cells were obtained from 10 young and 10 elderly normal subjects. The basal Hsp70 levels in the various PBL phenotypes were comparable between young and elderly subjects. However, different patterns of Hsp70 response were noticed among the PBL subtypes, which were similar in both young and elderly subjects. In particular, the memory cell phenotypes produced more Hsp70 than the naïve phenotypes. These results suggest that aging-related changes in basal Hsp70 levels in PBL are linked to the altered frequency of lymphocyte subsets and not to increases in aged lymphocytes per se. In addition, the increase in Hsp70 can be interpreted as the result of a tendency towards more pronounced cellular differentiation in aging.Aging cell 07/2008; 7(4):498-505. · 7.55 Impact Factor
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ABSTRACT: Providing food, energy and materials for the rising global population is a challenge which is compounded by increased pressure on natural resources such as land, water and fossil sources of raw materials. Greenhouse gas (GHG) emissions from human activities have increased with industrial development and population expansion, and it is anticipated that resulting climate change might further limit agricultural productivity, through changes to weather patterns and global availability/distribution of agriculturally productive land. Growing crops as feedstocks for industrial uses is seen as one way of reducing GHG emissions and dependency on fossil resources. However, determining the extent to which the development of crops for industrial use will effect GHG balances and provide for a more energy efficient manufacturing system requires the development and use of appropriate calculation methodologies.Research at the Porter Institute has identified over 250 different scenarios for bioenergy production systems using commodity crops. In order to rationalise this complexity and diversity, a modular approach to Life Cycle Assessment (LCA) and sustainability analysis has been taken. This allows characterisation of discrete sections of supply chains and enables comparisons to be made between different crop production systems, different process systems and different end product uses. The purposes of this paper are to introduce the concepts of biofuel GHG and sustainability metrics, to introduce the approach taken by our organization and to use the example of UK grown willow in a lignocellulosic ethanol production system to demonstrate how GHG emission outcomes can be reviewed for “new” crops and technologies.The results show a range of variation, in both growing and process systems and how outcomes such as energy and GHG balances can be affected by various activities.LCA methodologies provide data to inform governments and industry of the potential specific supply chains may have for energy and GHG saving. However, methodological approaches can also affect assessment outcomes. Unresolved issues in LCA methodology must also be evaluated e.g. impacts resulting from land use change. Sustainability assessments of crop growing systems, irrespective of the end use, also assist in the assessment of environmental impacts of supply chains. However, it is critical that data continue to be collected, analysed and reviewed, to ensure that the most appropriate crops are grown and processed for the most appropriate end use.Industrial Crops and Products 01/2011; 34(2):1332-1339. · 3.21 Impact Factor