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Mercury (Hg) exposure makes happen disease to humans and animals spreading in all body compartments, especially in liver and kidney. In these ones, copper, zinc, manganese and iron were investigated to assess perturbation of essential metals' homeostasis due to Hg chronic intoxication. Because L-arginine, is able to induce beneficial influence on immunologic functions on mice intoxicated with Hg, we also studied the efficiency of detoxification process before and after treatment with this aminoacid. Adding L-arginine to diet of the intoxicated mice we achieved a good restoration to normal homeostatic conditions.

Occupational exposure at low doses of lead induces a significant increase of TNF-alpha plasma levels. Recently has been showed the crucial role on atherosclerosis origin of this pro-inflammatory cytokine. It is assumable a contribution of lead in atherosclerosis course in exposed subjects.

Occupational or environmental exposure to various metals affects human health. In particular, mercury is known to affect the immune system adversely. Metallothioneins (MTs) are low molecular weight, cysteine-rich, intracellular proteins, with high affinity for bivalent metals of which they regulate intracellular concentrations, thereby being playing a fundamental role in metal homeostasis. MTs protect cells from stress, inflammation and free radical damage and are involved in zinc homeostasis. Zinc has an important role in the immune system because it is indispensable for the activation andfunctioning of the thymic hormone, thymulin, which in turn is involved in T-lymphocyte differentiation and maturation. MTs participate in the detoxification process following acute poisoning, and are expressed in the various tissues, as well as in chronic intoxication, where continuous stress and the persistent inflammatory state induce their over-expression. The present study was undertaken to gain insights into the potential mechanisms acting on the immune system/altering the immune status in the presence of low mercury concentrations. To do this, the genic expression of MT-I and the amount of active thymulin produced by thymic endothelial cells were studied in mice exposed to different doses of mercury.

Melatonin (MEL) affects the immune system by direct or indirect mechanisms. An involvement of the zinc pool in the immune-reconstituting effect of MEL in old mice has recently been documented. An altered zinc turnover and impaired immune functions are also evident in pinealectomized (px) mice. The present work investigates further the effect of "physiological" doses of MEL on the zinc pool and on thymic and peripheral immune functions in px mice. Daily injections of MEL (100 micrograms/mouse) for 1 month in px mice restored the crude zinc balance from negative to positive values. Thymic and peripheral immune functions, including plasma levels of interleukin-2, also recovered. The nontoxic effect of MEL on immune functions was observed in sham-operated mice. Because the half-life of MEL is very short (12 min), interruption of MEL treatment in px mice resulted, after 1 month, in a renewed negative crude zinc balance and a regression of immune functions. Both the zinc pool and immunological parameters were restored by 30 further days of MEL treatment. The existence of a significant correlation between zinc and thymic hormone after both cycles of MEL treatment clearly shows an involvement of the zinc pool in the immunoenhancing effects of MEL and thus suggests an inter-relationship between zinc and MEL in px mice. Moreover, the existence of significant positive correlations between zinc or thymulin and interleukin-2 suggests that interleukin-2 may participate in the action of MEL, via zinc, on thymic functions in px MEL-treated mice.

Udgivelsesdato: 2009-Jan Several studies have assessed changes in frequency of -174 interleukin (IL)-6 single nucleotide polymorphism (SNP) with age. If IL-6 tracks with disability and age-related diseases, then there should be reduction, in the oldest old, of the frequency of homozygous GG subjects, who produce higher IL-6 levels. However, discordant results have been obtained. To explore the relationship between this polymorphism and longevity, we analyzed individual data on long-living subjects and controls from eight case-control studies conducted in Europeans, using meta-analysis. There was no significant difference in the IL-6 genotype between the oldest old and controls (Odds Ratio [OR]=0.96; 95% C.I.: 0.77-1.20; p=0.71), but there was significant between-study heterogeneity (I2=55.5%). In a subgroup analyses when male centenarians from the three Italian studies were included, the frequency of the IL-6 -174 GG genotype was significantly lower than the other genotypes (OR=0.49; 95% C.I.: 0.31-0.80; p=0.004), with no evidence of heterogeneity (I2=0%). Our data supports a negative association between the GG genotype of IL-6 SNP and longevity in Italian centenarians, with males who carry the genotype being two times less likely to reach extreme old age compared with subjects carrying CC or CG genotypes. These findings were not replicated in other European groups suggesting a possible interaction between genetics, sex and environment in reaching longevity.

Abnormal increments of pro-inflammatory cytokines (IL-6 and TNF-alpha) characterize the outbreak of infectious diseases, which are the major cause of death in the elderly. A counterbalance to the inflammation is exerted by IL-10 with an inhibitory role on TNF-alpha production. As is well known, some cytokine gene polymorphisms influence the cytokine production, playing a role as susceptibility or resistance factors against immune-mediated and infectious disease. Genetic variations in the -308A/G locus for TNF-alpha seems to affect the clinical outcome of some infectious diseases. In fact, the -308A allele is associated with severe septic shock and death. On this basis, we have screened healthy old subjects, nonagenarians and old patients affected by the acute phase of chronic obstructive bronchitis and bronchopneumonia of bacteria origin for the -308G/A locus (PCR-RFLP). Subjects are grouped in A+ (AG, AA genotypes) and A- (GG genotype) and data on IL-6, TNF-alpha, IL-10, NK cell cytotoxicity, zinc and metallothioneins (MTs) gene expression (RT-PCR) were stratified according to different TNF-alpha genotypes. The frequency of the A allele was increased in infected patients in comparison with healthy old controls. No differences existed between A+ and A- young adult, old and nonagenarian controls in tested parameters. Conversely, A+-infected patients displayed elevated IL-6, TNF-alpha and MTmRNA, low IL-10 coupled with impaired NK cell cytotoxicity and lower zinc ion than A- patients. However, the data reported are gender independent. Therefore, the -308A polymorphism at the locus of TNF-alpha may be one of the susceptibility factor for infectious diseases in old persons, particularly considering its association to the increased release of pro-inflammatory cytokines and to the reduction of zinc release and MTs synthesis involved in the control of the inflammatory response. These data strongly suggest that the genetic screening of the -308G/A polymorphism may be a valid tool for identification of subjects needing a more appropriate therapy when affected by acute and/or recurrent infectious diseases.

Purpose: Zinc (Zn) plays an essential role in many biological processes including immune response. Impaired Zn status promotes immune dysfunction, and it has been associated with enhanced chronic inflammation during aging. It has been suggested that the measurement of circulating Zn by itself could not reflect the real Zn status of an individual. It is therefore necessary to identify other determinants associated with plasma Zn to better understanding how physiopathological conditions during aging may affect the concentration of this metal. Methods: We have investigated the association between Zn levels and some biomarkers in 1090 healthy elderly from five European countries to increase the accuracy in the assessment of the Zn status. Stepwise multivariate linear regression models were used to analyze the influence of factors such as age, dietary intake, inflammatory mediators, laboratory parameters and polymorphisms previously associated with Zn homeostasis. Results: Plasma Zn decrement was most strongly predicted by age, while positive correlations were found with albumin, RANTES and Zn intake after adjustment for multiple confounders. HSP70 +1267 AA genotype was an independent factor associated with Zn plasma concentrations. Cu/Zn ratio was positively associated with markers of systemic inflammation and age and negatively associated with albumin serum levels. Conclusions: Our findings show the most important independent determinants of plasma Zn concentration and Cu/Zn ratio variability in elderly population and suggest that the decline with age of Zn circulating levels is more dependent on physiopathological changes occurring with aging rather than to its nutritional intake.

Associations between copper to zinc ratio (CZr) and mortality have suggested CZr as a biomarker of aging. Nevertheless, very limited data exist on the association between serum CZr and physical or functional status of very old people. We examined the relationship between serum CZr and physical performance, muscle strength, functional status, and survival from the ilSIRENTE Study: a longitudinal study of persons aged 80 years or older (n = 346). An adjusted linear regression model was subsequently performed to calculate the regression coefficients of the associations between baseline physical and functional measures (dependent variable) with CZr or “Cu and Zn” alone taking also into account the influence of other relevant factors, including hematological (albumin, cholesterol, and urea) and inflammatory biomarkers (IL-6 and CRP) that were significantly different across CZr tertiles. CZr showed significant and stronger relationships than Cu or Zn alone with all baseline physical and functional measures in models that did not include adjustments for inflammatory parameters. CZr was also associated with physical decline, measured as “SPPB% decline” at 2 years of follow-up and mortality at 4 years of follow-up. Subjects in the high CZr tertile had a higher risk of death with an adjusted hazard ratio of 1.92 (95% CI, 1.12–3.29; p = 0.02). In conclusion, we have confirmed the role of CZr as a predictor of mortality, whereas the role of CZr as a biomarker or predictor of physical or functional performance seems to be the consequence of its strict relationships with inflammatory parameters. In this context, further investigations need to be carried out.

The elderly subjects affected by Acute Myocardial Infarction (AMI) have the highest risk of mortality. Our study was designed to improve the capability of mortality risk stratification in elderly AMI patients through the concurrent evaluations of different biomarkers, including genetic markers.One-year follow-up study was performed in 250 elderly AMI patients. The combination of high total Homocysteine (tHcy), low folate and vitamin B12 plasma levels (18.0+/-9.0 micromol/l; 4.4+/-1.2 ng/ml; 404.2+/-287.5 pg/ml, respectively) and elevated CRP plasma levels (or =6 mg/dl) identify the highest-risk pathway of heart mortality (RR=4.20, IC 95% 1.62-10.89, P0.002) with respect to the combination of low total tHcy, high folate and vitamin B12 plasma levels (12.4+/-5.2 micromol/l; 8.9+/-2.5 ng/ml; 546.9+/-379.8 pg/ml, respectively) and low CRP plasma levels (6 mg/dl).In elderly AMI patients the concomitant elevation of CRP and tHcy, associated with folate and vitamin B12 low levels, could be considered a significant predictive heart mortality risk factor.

Aging is an inevitable biological process that is associated with gradual and spontaneous biochemical and physiological changes and increased susceptibility to diseases. Because nutritional factors are involved in improving immune functions, metabolic harmony, and antioxidant defense, some nutritional factors, such as zinc, may modify susceptibility to disease and promote healthy aging. In vitro (human lymphocytes exposed to endotoxins) and in vivo (old or young mice fed with low zinc dietary intake) studies revealed that zinc is important for immune efficiency (innate and adaptive), antioxidant activity (supeoxide dismutase), and cell differentiation via clusterin/apolipoprotein J. Intracellular zinc homeostasis is regulated by metallothioneins (MT) via ion release through the reduction of thiol groups in the MT molecule. This process is crucial in aging because high MT levels are not able to release zinc, resulting in low intracellular free ion availability for biological functions. Improvement in these functions occurs in the elderly after physiological zinc supplementation. In this study, the selection of elderly subjects for zinc supplementation is discussed in relation to the genetic background of MT and pro-inflammatory cytokines, such as interleukin-6, because the latter is involved both in MT-gene expression and in intracellular zinc homeostasis.

Carotid artery stenosis (CS) is a well-established risk factor for stroke. Increased proinflammatory chemokines, enhanced metallothionein (MT), and altered metal homeostasis may play roles in atherosclerosis progression and plaque destabilization. MT may sequester zinc during chronic inflammation, provoke zinc deficiency, and modulate NK cell cytotoxicity. A recent investigation of older patients with diabetes and atherosclerosis showed an association between the −209 A/G MT2A polymorphism, CS, and zinc status. In this study, we evaluated the relationship between two MT2A polymorphisms (−209 and + 838 locus), metal status, and inflammatory/immune response in older patients with CS only (the CS1 group) or with CS and previous cerebrovascular episodes (transient ischemic attack or stroke) (the CS2 group). A total of 506 individuals (188 CS1, 100 CS2, and 218 healthy controls) were studied. Atherosclerotic patients (CS1 and CS2) showed increased levels of MT, MCP-1, and RANTES, reduced NK cell cytotoxicity, and altered trace element concentrations (zinc, copper, magnesium, iron). The +838 C/G MT2A polymorphism was differently distributed in CS1 and CS2 patients, who displayed the GG genotype (C−) with significantly higher frequency than elderly controls. C− carriers showed increased MCP-1 and decreased NK cell cytotoxicity, CD56+ cells, and intracellular zinc availability along with decreased zinc, copper, and magnesium content in erythrocytes and increased iron in plasma. C− carriers also showed a major incidence of soft carotid plaques. In conclusion, the +838 C/G MT2A polymorphism seems to influence inflammatory markers, zinc availability, NK cell cytotoxicity, and trace element status, all of which may promote CS development.

The primary role of the immune system is to protect the organism against pathogens, but age-associated alterations to immunity increase the susceptibility of the elderly to infectious disease. The exact nature of these changes is still controversial, but the use of screening procedures, such as the SENIEUR protocol to exclude underlying illness, helped to better characterize the changes actually related to physiological aging rather than pathology. It is generally agreed that the most marked changes occur in the cellular immune response reflecting profound alterations in T cells. Much of this is due to thymic involution as well as changes in the proportions of T cell subpopulations resulting from antigen exposure, and altered T cell activation pathways. However, a body of data indicates that innate immune responses, including the critical bridge between innate and adaptive immunity, and antigen presenting capacity are not completely resistant to senescence processes. The consequences of all these alterations are an increased incidence of infections, as well as possibly cancers, autoimmune disorders, and chronic inflammatory diseases. The leading question is what, if anything, can we do to prevent these deleterious changes without dangerously dysregulating the precarious balance of productive immunity versus immunopathology? There are many potential new therapeutic means now available to modulate immunosenescence and many others are expected to be available shortly. One main problem in applying these experimental therapies is ethical: there is a common feeling that as ageing is not a disease; the elderly are not sick and therefore do not require adventurous therapies with unpredictable side-effects in mostly frail individuals. Animal models are not helpful in this context. In this chapter we will first briefly review what we think we know about human immunosenescence and its consequences for the health status of elderly individuals. We will then discuss possible interventions that might one day become applicable in an appropriate ethical environment.

Objective To examine the relationship between job satisfaction, psychological distress, psychosocial processes and stress-related biological factors, and to evaluate whether over time changes of work satisfaction could affect the immunological-inflammatory status of workers. Methods One hundred and one nurses were enrolled at the Clinic of Occupational Medicine, Polytechnic University of Marche, Ancona, Italy. Perceived job satisfaction, psychological distress, and social support were assessed every 4 mo over a 1-yr period using 4 self-reported questionnaires. T lymphocytes CD3, CD4(+), CD8(+), CD8(+)-CD57(+), B lymphocyte CD19(+), NK cells CD56(+), and NK cell activity were determined. Results Job satisfaction was associated with reduced psychological distress and was characterized by low cell numbers of CD8(+) suppressor T cells, CD8(+)-CD57(+) activated T cells, CD56(+) NK cells and low IL-6 levels. Over time changes in psychological parameters were related to changes in the immunological-inflammatory variables. Subjects who increased their job satisfaction showed a reduced psychological stress associated with reduced number of CD8(+)-CD57(+) activated T cells and inflammatory cytokines. Conclusions Job (dis)satisfaction is related with psychological mechanisms in stress affecting cellular immune function.

Inflammation and genetics are prominent mechanisms in the pathogenesis of atherosclerosis (AT) and its complications. In this review we discuss the possible impact on AT development of several genetic determinants involved in inflammation, oxidative stress and cytoprotection (IL-6, TNF-alpha, IL-10, CD14, TLR4, MT, HSP70). Genetic polymorphisms of these genes may affect a differential inflammatory response predisposing to AT. However, allelic polymorphisms of genes which increase the risk of AT frequently occur in the general population but, only adequate gene-environment-polymorphism interactions promote the onset of the disease. Zinc deficiency has been suggested as an environmental risk factor for AT. With advancing age, the incidence of zinc deficiency increases for several reasons. Among them, dietary intake, malabsorption and genetic background of inflammatory markers may be involved. A crucial contribution may also be played by increased oxidative stress which may lead to the appearance of dysfunctional proteins, including metallothioneins (MT) that are in turn involved in zinc homeostasis. The detection of candidate genes related to inflammation and promoting AT and their reciprocal influence/interaction with zinc status might allow earlier appropriate dietary interventions in genetically susceptible subjects.

Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease which in Western society mainly accounts for clinical dementia. AD has been linked to inflammation and metal biological pathway. Neuro-pathological hallmarks are senile plaques, resulting from the accumulation of several proteins and an inflammatory reaction around deposits of amyloid, a fibrillar protein, Abeta, product of cleavage of a much larger protein, the beta-amyloid precursor protein (APP) and neurofibrillary tangles. Amyloid deposition, due to the accumulation of Abeta peptide, is the main pathogenetic mechanism. Inflammation clearly occurs in pathologically vulnerable regions of AD and several inflammatory factors influencing AD development, i.e. environmental factors (pro-inflammatory phenotype) and/or genetic factors (pro-inflammatory genotype) have been described. At the biochemical level metals such as zinc are known to accelerate the aggregation of the amyloid peptide and play a role in the control of inflammatory responses. In particular, zinc availability may regulate mRNA cytokine expression, so influencing inflammatory network phenotypic expression.

Coronary artery disease (CAD) is characterized by an inflammatory status and it represents the major cause of death in elderly. Zinc deficiency and inflammatory genes within major histocompatibility complex (MHC) region are implicated in ischaemic heart diseases. TNF-alpha is present in coronary artery plaques and may provoke plaque instability. Hsp70 plays instead a pro-atherogenic role, via proinflammatory cytokine production, in atherosclerotic lesions contributing to plaque rupture. Contradictory data report the association between -308 TNF-alpha polymorphism and CAD, while no investigations exist on Hsp70-2 gene in CAD. In the current study, we analysed -308 TNF-alpha and 1267 Hsp70-2 polymorphisms and zinc status in 190 healthy old controls and 216 old patients with carotid stenosis subdivided in two groups: the first one 105 patients with CAD (C group), and the second one 111 patients without cardiovascular events (D group). We found a lack of association between -308 TNF-alpha polymorphism and CAD. Conversely, 1267 Hsp70-2 polymorphism was associated with CAD. In particular, significant higher frequency of AB + BB genotypes (B + genotype) was observed in C patients than controls (71.4 vs.56.9%, P = 0.017, odds ratio = 1.898). However, when C patients were subdivided into four subgroups on the basis of presence/absence of 1267B Hsp70-2 and -308A TNF-alpha alleles, B + A + patients showed higher prothrombin activity as well as Hsp70-2, TNF-alpha, IL-6 gene expressions in carotid atheroma when compared to B - A - genotypes. The zinc status (plasma and Zn/Fe ratio in erythrocytes) is not affected by these polymorphisms. However, zinc deficiency is present in CAD condition. In conclusion, 1267 HSP70-2 polymorphism and zinc deficiency, rather than -308 TNF-alpha, are independently associated with CAD. B + A+ and B + A- carriers seem more predisposed to ischaemic events; conversely, B - A- genotype may be considered a protective marker against CAD.

Cardiovascular diseases (CVD), such as myocardial infarction (MI), are major causes of disability and mortality in the elderly. The increasing burden of CVD in ageing industrialized populations requires intensive research in order to improve preventive and therapeutic strategies especially in old people and if possible slow the processes of cardiovascular disease generation and progression. Ageing is accompanied by an age-dependent up-regulation of the inflammatory response, due to chronic antigenic stress stimulation, which potentially triggers the onset of inflammatory diseases, especially CVD. However, the exact mechanisms are still poorly understood. Since CVD are caused by interactions between genetic and environmental factors, a possible approach to their prevention is to identify the potential genetic component of inflammatory cardiovascular risk factors, providing the basis for personalized lifestyle modification and improved pharmacological therapy. Some common gene polymorphisms associated with high production of inflammatory molecules have been associated with atherosclerosis. Therefore, controlling inflammation might play a protective role against CVD, especially in ageing. Although a large number of studies of pro- and anti-inflammatory gene variants in association with CVD and MI exists, the emerging data are quite conflicting and do not provide definitive evidence for a role of these polymorphisms in the pathogenesis of MI. In this paper we review the evidence for a possible role of genetic polymorphisms of the most important inflammatory cytokines (IL-6, TNF-α, IL-10) and immune receptors (CD14 receptor and TLR-4) in modulating the incidence or the prognosis of MI, with a special focus in ageing population.

ASTRACT Longevity seems to be directly correlated with optimal functioning of the immune system, suggesting that some genetic determinants of longevity might reside in those polymorphisms for the immune system genes that regulate immune responses. Accordingly, mouse lifespan is influenced by MHC (major histocompatibility complex) genotype. The HLA (the human MHC) region encompasses over 4 Mb of DNA on the chromosome band 6p21.3 and its extensive characterisation has recently culminated in the determination of the nucleotide sequence of the entire region, confirming the presence of ~ 220 genes. The MHC is traditionally divided into the class I, class II and class III regions. Most HLA genes involved in the immune response fall into classes I and II, which encode highly polymorphic heterodimeric glycoproteins involved in graft rejection and antigen presentation to T cells. However, many genes of the class III region are also involved in the immune and inflammatory responses.. MHC polymorphisms have been the focus of a vast number of ageing association studies. One of the limitations in the most reported studies is the number of aged individuals available of both genders, and the lack of complete background histories of health or ethnicity for study participants. However, also taking into account well planned and designed studies, discordant results have been obtained. The discordant results of MHC/ageing association studies might be due to distinct linkage in different cohorts or to other interacting, genetic or environmental factors or to the heterogeneity of ageing. Nevertheless, bearing all the reported studies in mind, there is no convincing evidence of a strong, direct association between longevity and any MHC alleles.

High levels of IL-6 are coupled with impaired immune efficiency, morbidity and mortality in ageing. Elderly men with GG (C−) genotype in −174 locus of IL-6 promoter are disadvantaged for longevity due to higher IL-6 than CG or CC (C+) carriers. As IL-6 increases in atherosclerosis, the study of the polymorphism of IL-6 may be a useful tool in identifying old subjects at risk for atherosclerosis. Thus, we divided old men into C+ and C− genotypes. Natural killer (NK) cell cytotoxicity, IL-6, IL-10, TNF-α, MTmRNA and zinc ion bioavailability were also evaluated and compared with nonagenarians and old patients affected by carotid stenosis. Old C− patients display, other than elevated IL-6, higher IL-10, TNF-α and MTmRNA coupled with impaired NK cell cytotoxicity and lower zinc ion bioavailability than C+ patients. The same trend is observed in old subjects with C− phenotype. Nonagenarians with C+ genotype show less inflammation, low MTmRNA, satisfactory NK cell cytotoxicity and good zinc bioavailability than long-living individuals with C− genotype. A higher degree of bilateral carotid stenosis is observed in C− patients than in C+ patients (88 vs 52%). Therefore, C− genotype is coupled with chronic inflammation, impaired immune efficiency, low zinc ion bioavailability and high MTmRNA. As such, C− genotype is a risk factor for the appearance of severe atherosclerosis. Thus, the polymorphism of IL-6, together with the analysis of zinc turnover and immune parameters, is of a great clinical relevance in order to genetically identify old subjects at risk in developing severe atherosclerosis and, at the same time, to predict subjects predestined to successful ageing. As a consequence, more convenient therapies may be prepared for a complete recovery.

Lifelong antigenic burden determines a condition of chronic inflammation, with increased lymphocyte activation and pro-inflammatory cytokine production. A large number of studies have documented changes in Zn metabolism in experimental animal models of acute and chronic inflammation and in human chronic inflammatory diseases. In particular, modification of zinc plasma concentration as well as intracellular disturbance of antioxidant intracellular pathways have been found associated to age-related inflammatory diseases, like atherosclerosis. Zinc deficiency is extremely diffused in aged people that are educated to avoid meat and other high Zn-content foods due to fear of cholesterol. Rather, they increase consumption of refined wheat products that lack of Zn, magnesium and other critical nutrients in consequence of refining process. On the other hand, plasma concentration of metallic ions like Zn is influenced by pro-inflammatory cytokines production. A major target of Zn may be NF-kB, a transcription factor critical for the expression of many pro-inflammatory cytokines whose production is finely regulated by extra- and intracellular activating and inhibiting factors interacting with regulatory elements on cytokine genes. Moreover, this factor is regulated by the expression of specific cellular genes involved in inflammation. So it is not surprising that Zn deficiency is constantly observed in aged patients affected by infectious diseases. On the other hand, cytokine genes are highly polymorphic and some of these polymorphisms have been found associated to age-related diseases as atherosclerosis. Therefore, Zn deficiency in individuals genetically predisposed to a dis-regulation of inflammation response, may play a crucial role, in causing adverse events and in reducing the probability of a successful aging.