The Genetics of Innate Immunity and Inflammation in Ageing, Age-Related Diseases and Longevity

Inflammation is a key component of age-related diseases such as atherosclerosis and Alzheimer’s disease (AD) and genes coding for inflammatory or anti-inflammatory molecules are, therefore, good candidates for influencing the risk of developing these pathologies. Findings discussed in this chapter suggest that different alleles of genes coding for pro-or anti-inflammatory genes may affect individual life-span expectancy by influencing the type and intensity of immune-inflammatory responses against environmental stressors involved in the development of age-related disease. Our immune system has evolved to control pathogens and so pro-inflammatory responses are likely to be evolutionarily pro…

Pro-inflammatory gene variants in myocardial infarction and longevity: implications for pharmacogenomics.

Inflammation and genetics play an important role in the pathogenesis of coronary heart disease (CHD). However, despite the increasing appreciation of the role of genetics in CHD and myocardial infarction (MI) pathogenesis, pharmacogenomic approaches to uncover drug target have not been extensively explored. Cyclo-oxygenases (COXs) and 5-lipoxygenase (5-LO) are the key enzymes in the conversion of arachidonic acid to prostaglandins (PG) and leukotrienes (LT) and are implicated in a wide variety of inflammatory disorders, including atherosclerosis. In fact, PGE2 activates Matrix Metallo-proteinases whereas LTB4 is a chemoactractant for monocytes and activates gene expression in inflammatory c…

Inflammation, genes and zinc in Alzheimer's disease.

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 i…

Zinc and inflammatory/immune response in aging

Life-long antigenic burden determines a condition of chronic inflammation, with increased lymphocyte activation and proinflammatory cytokine production. A large number of studies have documented changes in zinc metabolism in experimental animal models of acute and chronic inflammation and in human chronic inflammatory conditions. In particular, modification of zinc plasma concentration, as well as intracellular disturbance of antioxidant intracellular pathways, has been found in aging and in some age-related diseases. Zinc deficiency is diffused in aged individuals in order to avoid meat and other high zinc content foods due to fear of cholesterol. Rather, they increase the consumption of r…

A study of serum immunoglobulin levels in elderly persons that provides new insights into B cell immunosenescence.

The literature on immunosenescence has focused mainly on T cell impairment. With the aim of gaining insight into B cell immunosenescence, we investigated the serum immunoglobulin levels in a cohort of 166 subjects (20-106 years). Serum IgG (and IgG subclasses) were quantified by the nephelometric technique, IgE by CAP system fluorescence enzyme immunoassay, and IgD by radial immunodiffusion (RID). There was an age-related increase of IgG and IgA; the IgG age-related increase was significant only in men, but IgG1 levels showed an age-related increase both in men and women, whereas IgG3 showed an age-related increase only in men. IgE levels remain unchanged, whereas IgD and IgM serum levels d…

In vitro treatment with interleukin-2 normalizes type-1 cytokine production by lymphocytes from elderly

The term immunosenescence is taken to mean the deterioration of immune function seen in elderly, which is manifested in increased susceptibility to infectious diseases, neoplasias, and autoimmune diseases. It is only recently that we have begun to understand the cellular and molecular changes involved. Of special interest in this regard are observations of a decline in synthesis of Type-1 cytokines which predisposes to diminished cell mediated immunity. We have evaluated the production of type 1 cytokines in old and young donors either in presence or in absence of recombinant interleukin-2 (rIL-2). Lymphocytes were stimulated with plastic bound anti-CD3 and after 48 h the supernatants were …

Alpha1-antitrypsin heterozygosity plays a positive role in attainment of longevity.

Genes involved in cardiovascular diseases (CVD) play an opposite role in human longevity. The alpha1-antitrypsin (AAT) is a serine-protease inhibitor required for the prevention of proteolytic tissue damage, by neutrophil elastase. The role of AAT in CVD has not been definitively assessed and its effect on longevity has not yet fully been studied. To clarify these points, we have studied the distribution of AAT allele variants in 3 cohorts: 127 young patients affected by acute myocardial infarction (AMI), 255 young controls and 143 centenarians from Sicily. The Z allele frequency was most frequent in centenarians (13.3%), intermediate in healthy young controls (3.1%) and less frequent in AM…

A Pilot Study on Prostate Cancer Risk and Pro-Inflammatory Genotypes: Pathophysiology and Therapeutic Implications

Host genetic factors are crucial risk determinants for many human cancers. In this framework, an interesting model is represented by prostate cancer (PC), which is featured by a complex pathophysiology with a strong genetic component. Multiple genes seem to influence PC risk and several single nucleotide polymorphisms (SNPs) of candidate genes modifying PC susceptibility have been identified. It is noteworthy the potential association of common SNPs in pro-inflammatory genes with PC risk, since chronic inflammation is assumed to play a key role in prostate carcinogenesis. With the aim to identify candidate genes as an experimental basis to develop new strategies for both prevention and trea…

Systemic inflammatory response in erderly patients following hernioplastical operation

Abstract The number of old and oldest old patients undergoing surgery of varying severity is increasing. Ageing is a process that changes the performances of most physiological systems and increases susceptibility to diseases and death; accordingly, host responses to surgical stress are altered with ageing and the occurrence of age-related increase in susceptibility to post-operative complications has been claimed. Twenty-four male patients undergoing Lichtenstein (LH) hernioplasty for unilateral inguinal hernia were included in this study and divided in two groups (Young and Old respectively), according to their age. As expression of the acute phase response, we measured changes in concent…

Effects of in vitro treatment with fluticasone propionate on natural killer and lymphokine-induced killer activity in asthmatic and healthy individuals.

Background: Topical corticosteroids are beneficial in the treatment of allergic respiratory disorders; they exert effects on a number of cells involved in allergic inflammatory reactions. On the other hand, major histocompatibility complex (MHC)-unrestricted cytotoxicity (i.e., natural killer [NK] cell activity) may play a role in the inflammatory allergic reaction. The objective was to gain insight into the mechanisms of the therapeutic effects of fluticasone propionate (FP), an inhaled corticosteroid used in asthma and rhinitis therapy. Therefore, we evaluated the NK and lymphokine-activated killer (LAK) activity of effector cells in vitro treated or not with FP. Methods: Evaluations were…

Memory B Cell Subpopulations in the Aged

The literature on immunosenescence has focused mainly on T cell impairment. With the aim of gaining insight into B cell immunosenescence, the authors investigated the serum IgD levels in 24 young and 21 old people and analyzed their relationship with the number of CD19 CD27 memory cells. Serum IgD were quantified by the use of radial immunodiffusion and the lymphocyte population CD19 CD27 was identified by a FACScan flow cytometer. Serum IgD levels were significantly lower (p 0.0001) in old subjects, and the percentage of CD19 CD27 lymphocytes were significantly increased (p 0.01) in old subjects. Finally, a significant negative correlation was found (p 0.01) between serum concentrations of…

Association between the HLA-DR alleles and longevity: a study in Sardinian population

Human longevity may be correlated with optimal functioning of the immune system, suggesting that genetic determinants of longevity also resides in those polymorphisms for the immune system genes that regulate immune responses as histocompatibility (HLA) antigens. However, conflicting results have been obtained. Some well planned and designed association studies performed in Caucasians suggest that longevity is associated with positive selection of alleles (i.e. HLA-DR11) or haplotypes (i.e. HLA-B8,DR3) that confer resistance to infectious diseases, respectively, via peptide presentation or via antigen non-specific control of immune response. Association studies are subjected to a number of …

Association between +1059G/C CRP polymorphism and acute myocardial infarction in a cohort of patients from Sicily: a pilot study.

Inflammation plays a role in all the phases of atherosclerosis, and increased production of the acute-phase reactant, C-reactive protein (CRP), predicts future cardiovascular events. Furthermore, CRP has been claimed to play a role in the pathogenesis of atherosclerosis; therefore, CRP polymorphisms might be associated with acute myocardial infarction (AMI). We have analyzed male patients affected by AMI and healthy age-related male controls from Sicily for +1059G/C CRP single-nucleotide polymorphism (SNP). There was a significantly higher frequency of +1059C SNP (P = 0.0008; OR 3.86) in patients compared to controls. CRP serum levels were significantly higher in C+ healthy subjects rather …

Immunoproteasome LMP2 60HH Variant Alters MBP Epitope Generation and Reduces the Risk to Develop Multiple Sclerosis in Italian Female Population

BackgroundAlbeit several studies pointed out the pivotal role that CD4+T cells have in Multiple Sclerosis, the CD8+ T cells involvement in the pathology is still in its early phases of investigation. Proteasome degradation is the key step in the production of MHC class I-restricted epitopes and therefore its activity could be an important element in the activation and regulation of autoreactive CD8+ T cells in Multiple Sclerosis.Methodology/principal findingsImmunoproteasomes and PA28-alphabeta regulator are present in MS affected brain area and accumulated in plaques. They are expressed in cell types supposed to be involved in MS development such as neurons, endothelial cells, oligodendroc…

Pharmacogenomics: a tool to prevent and cure coronary heart disease.

Inflammation and genetics play an important role in the pathogenesis of coronary heart disease (CHD). This is supported by epidemiological studies which have thoroughly investigated the association between CHD and gene polymorphisms of the inflammatory molecules. Moreover, efforts to find elective therapy have not been rewarding and, despite the increasing appreciation of the role of genetics in CHD and myocardial infarction (MI) pathogenesis, pharmacogenomic approaches to uncover drug target have not been extensively explored. A critical search of published literature has suggested few inflammatory genes directly involved in the risk to develop CHD and MI. The selected genes are, the pro- …

Gender-Related Immune-Inflammatory Factors, Age-Related Diseases, and Longevity

This review discusses the role of estrogens as pro- or antiinflammatory players in immune-inflammatory responses. In particular, their role in Alzheimer’s disease (AD), an example of immune-inflammatory disease, is discussed briefly. AD is a progressive neurodegenerative disease, which in Western societies accounts for the majority of cases of clinical senile dementia. However, sexual dimorphism of diseases may also depend on factors independent of sex hormones (i.e., a gender effect), as demonstrated by our data on differential longevity in females and males. In fact, differences in mortality between men and women are not only a question of sex that refers to biological differences, but ra…

Role of cyclooxygenae-2 and 5-lypoxygenase polymorphisms in Alzheimer's disease in a population from northern Italy:implications for pharmacogenomics

Alzheimer's disease (AD) is a neurodegenerative disorder clinically characterized by cognitive deficit with progressive worsening of memory. Recent data indicate that neurons, as well as other brain cells, can express enzymes such as cyclooxygenases (COXs) and 5-lipoxygenase (5-LO) which are considered important in inflammatory cells. Moreover, it has been demonstrated that COX-2 and 5-LO enzymes play a considerable role in the pathophysiology of AD. In order to assess the possible role of COX-2 and 5-LO single nucleotide polymorphisms (SNPs) in AD, we examined their distribution in 341 AD patients and 190 controls from Northern Italy. A significant difference was observed in the distributi…

Immunosenescence and anti-immunosenescence therapies: the case of probiotics.

ABSTRACT Aging is a complex process that negatively impacts the development of the immune system and its ability to function. Progressive changes in the T and B cell systems over the life span have a major impact on the capacity to respond to immune challenge. These cumulative age-associated changes in immune competence are termed immunosenescence. This process is mostly characterized by: (1) shrinkage of the T cell repertoire and accumulation of oligoclonal expansions of memory/effector cells directed toward ubiquitary infectious agents; (2) involution of the thymus and the exhaustion of naive T cells; and (3) chronic inflammatory status. Here we discuss possible strategies to counteract t…

Polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein are associated with chronic spontaneous urticaria and urinary leukotriene E4

The mechanisms of chronic spontaneous urticaria (CSU) continue to be unknown. Our working hypothesis is that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be involved in the pathways leading to CSU. We examined five candidate polymorphisms of cyclo-oxygenases 1 and 2 and of 5-lipo-oxygenase-activating protein in 109 controls and in 94 CSU patients from Northern Italy. We also examined the levels of urinary leukotriene E4 (LTE4) before and after challenge with ASA. A multiple regression model was found to show that COX-2 5'UTR T/G, COX-2 Exon 10 T/C, and FLAP -336 G/A polymorphisms were significantly associated with CSU, with the minor allele more represented …

Role of TLR Polymorphisms in Immunosenescence

Innate immunity provides a first line of host defense against infection through microbial recognition and killing while simultaneously activating a clonotypic immune response. Toll-like receptors (TLRs) are principal mediators of rapid microbial recognition and function mainly by detection of pathogen-associated molecular patterns (PAMPs) that do not exist in the host. The different members of TLRs recognize several PAMPs, such as peptidoglycan for TLR2, lipopolysaccharide (LPS) for TLR4, flagellin for TLR5, and CpGDNA-repeats for TLR9. Several endogenous ligands of various TLRs have been also identified in the host. In this chapter, we describe the involvement of TLR-4 polymorphisms in imm…

Association Between the HLA-A2 Allele and Alzheimer Disease

In the elderly, the most common cause of dementia is Alzheimer disease (AD), which is responsible for the age-related progressive neurodegenerative inflammatory condition mediated by the disease. It has been seen that several genetic and environmental factors are involved in AD onset. Epidemiologic data suggest that some genetic determinants of AD might reside in those polymorphisms that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, several MHC polymorphisms have been in the spotlight of a large number of AD association studies. A possible association of HLA-A2 allele with increased susceptibility to AD has been the subject of debate …

HLA and KIR Frequencies in Sicilian Centenarians

Several studies suggest that human longevity appears to be linked inextricably with optimal functioning of the immune system, suggesting that specific genetic determinants may reside in loci that regulate the immune response, as human leukocyte antigen (HLA) and killer cell immunoglobulin-like receptor (KIR) genes. It has been suggested that longevity is associated with positive selection of alleles (i.e., HLA-DR11) or haplotypes (i.e., HLA-B8,DR3) that confer resistance to infectious disease(s). On the other hand, the cytolytic activity of natural killer (NK) cells is controlled by activating and inhibitory cell-surface receptors, including KIR. The genetic diversity of the KIR loci with r…

CCR5 Receptor: Biologic and Genetic Implications in Age-Related Diseases

The CC chemokine receptor 5 (CCR5) is a member of CC-chemokine receptor family. CCR5 has the characteristic structure of a seven transmembrane G protein-coupled receptor (GPCR), which regulates trafficking and effector functions of memory/effector Th1 cells, macrophages, NK cells, and immature dendritic cells. CCR5 and its ligands are important molecules in viral pathogenesis. CCR5 represents the co-receptor for macrophage (M) and dual (T cell and M)-tropic immunodeficiency viruses. Recent evidence has also demonstrated the role of CCR5 in a variety of human diseases, ranging from infectious and inflammatory diseases to cancer. In this article, we describe the involvement of CCR5 in two age…

Role of proinflammatory alleles in longevity and atherosclerosis: results of studies performed on -1562C/T MMP-9 in centenarians and myocardial infarction patients from Sicily.

Centenarians are characterized by marked delay or escape from age-associated diseases that cause mortality at earlier ages. Jointly, atherosclerosis and its complications, such as myocardial infarction (AMI), significantly contribute to mortality in the elderly. Inflammation is a key component of atherosclerosis and inflammatory genes are good candidates for the risk of the development of atherosclerosis. Genetic traits contribute to the risk of AMI and allelic variations in inflammatory genes should boost the risk of disease. If proinflammatory genotypes significantly contribute to the risk of AMI, alleles associated with disease susceptibility should not be included in the genetic backgro…

Polymorphisms of pro-inflammatory genes and Alzheimer's disease risk: A pharmacogenomic approach.

Clinically and pathologically Alzheimer's disease (AD) represents a sequential progressive neurodegenerative disorder. AD is etiologically heterogeneous and accounts for a majority of dementia in western societies. Inflammation clearly occurs in pathologically vulnerable regions of the AD brain and the search for genetic factors influencing the pathogenesis of AD has lead to the identification of numerous gene polymorphisms that might act as susceptibility modifiers. Accordingly, several reports have indicated that the risk of AD is substantially influenced by several genetic polymorphisms in the promoter region, or other untranslated regions, of genes encoding inflammatory mediators, altho…

Association between the polymorphism of CCR5 and Alzheimer's disease: results of a study performed on male and female patients from Northern Italy.

Alzheimer's disease (AD) is the most common cause of dementia in Western society. The prevalence of AD is greater in women than in men, largely due to longevity and survival differences favoring women. However, some studies suggest that incidence rates may really be increased in women. One possible factor influencing AD incidence in women is the loss of ovarian estrogens production after menopause, which might be involved in AD pathogenesis. Estrogens seem to influence some neuronal functions. Many of these actions appear beneficial (i.e., neuroprotective action against a variety of insults, as oxidative stress, and reduction of beta-amyloid plaques formation). Furthermore, several studies …

Polymorphisms of pro-inflammatory genes and prostate cancer risk: a pharmacogenomic approach.

In this paper, we consider the role of the genetics of inflammation in the pathophysiology of prostate cancer (PCa). This paper is not an extensive review of the literature, rather it is an expert opinion based on data from authors' laboratories on age-related diseases and inflammation. The aim is the detection of a risk profile that potentially allows both the early identification of individuals at risk for disease and the possible discovery of potential targets for medication. In fact, a major goal of clinical research is to improve early detection of age-related diseases, cancer included, by developing tools to move diagnosis backward in disease temporal course, i.e., before the clinical…

Age-Related Inflammatory Diseases: Role of Genetics and Gender in the Pathophysiology of Alzheimer's Disease

Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease which in Western societies mainly accounts for clinical dementia. A high proportion of women are affected by this disease, especially at a very advanced age, which might to a large extent be associated with the fact that women live longer. However, some studies suggest that incidence rates may be really increased in women. For this reason the influence of estrogens on the brain and the decrease of it during menopause are of special interest. After menopause, circulating levels of estrogens markedly decline, influencing several brain processes predicted to influence AD risk. The control of estrogens on oxid…

LPS-mediated production of pro/anti-inflammatory cytokines and eicosanoids in whole blood samples: Biological effects of +896A/G TLR4 polymorphism in a Sicilian population of healthy subjects

Toll-like receptors (TLRs) are the principal mediators of rapid microbial recognition: the lipopolysaccharide (LPS) receptor TLR4 seems to have a paradigmatic role. Single nucleotide polymorphisms (SNPs) in the TLR4 gene, such as +896A/G, known to attenuate receptor signaling, have been described. The +896A/G SNP is significantly less frequent in patients with myocardial infarction, Alzheimer's disease or prostate cancer, whereas it is overrepresented in centenarians. To clarify and confirm the biological effects of +896A/G SNP and its role in the pathophysiology of age-related diseases and longevity, we assessed the levels of IL-6, TNF-α, IL-10 and eicosanoids (LTB4 and PGE2) in LPS-stimul…

Inflammation, genes and zinc in ageing and age-related diseases.

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,…

Granulocyte and natural killer activity in the elderly

The deterioration of the immune system in ageing, 'immunosenescence', is thought to contribute to increased morbidity and mortality from infections and possibly autoimmune diseases and cancer. The most profound changes involve effector and immunoregulatory T-cell functions. Immunosenescence appears also to be related to changes in non specific immunity as well. In the present study we have assessed superoxide production, chemotaxis and the expression of the apoptosis-related molecule APO1/Fas (CD95) on neutrophils (PMN) from young and old subjects. Furthermore, we have measured the basal natural killer (NK) activity of young and elderly subjects and we have compared the number of CD16+ cell…

Association between platelet endothelial cellular adhesion molecule 1 (PECAM-1/CD31) polymorphisms and acute myocardial infarction: a study in patients from Sicily

Summary Adhesion of circulating cells to the arterial surface is among the first detectable events in atherogenesis. Cellular adhesion molecules, expressed by the vascular endothelium and by circulating leucocytes, mediate cell recruitment and their transendothelial migration. Platelet endothelial cellular adhesion molecule 1 (PECAM-1/CD31), involved in this migration, has been associated with the developmental course of atherosclerosis. A few studies have investigated an association between coronary heart disease and single nucleotide polymorphisms (SNPs) located in functionally important domains of the PECAM-1/CD31 gene. In particular, Ser563Asn and Gly670Arg SNPs have been described as s…

Immunogenetics, Gender, and Longevity

In this article we discuss relevant data on aging, longevity, and gender with particular focus on inflammation gene polymorphisms which could affect an individual's chance to reach the extreme limit of human life. The present review is not an extensive revision of the literature, but rather an expert opinion based on selected data from the authors' laboratories. In 2000-2005 in the more developed regions, the life expectancy at birth is 71.9 years for men (78.3 in Japan) and 79.3 years for women (86.3 in Japan). Indeed, gender accounts for important differences in the prevalence of a variety of age-related diseases. Considering people of far-advanced age, demographic data document a clear-c…

Association Between Platelet Endothelial Cellular Adhesion Molecule-1 Polymorphisms and Atherosclerosis: Results of a Study on Patients from Northern Italy

Adhesion of circulating cells to the arterial surface is among the first detectable events in atherogenesis. Cellular adhesion molecules, expressed by the vascular endothelium and by circulating leukocytes, mediate cell recruitment and their transendothelial migration. Platelet endothelial cellular adhesion molecule-1 (PECAM-1), involved in this migration, has been associated with the development of atherosclerosis. Studies have investigated an association between coronary artery disease (CAD) and single-nucleotide polymorphisms (SNPs) located in functionally important domains of the PECAM-1 gene with inconsistent results. Thus, we have analyzed the distribution of V125L, N563S, and G670R S…

Inflammation, Longevity, and Cardiovascular Diseases: Role of Polymorphisms of TLR4

The total burden of infection at various sites may affect the progression of atherosclerosis, the risk being modulated by host genotype. The role of lipopolysaccaride receptor TLR4 is paradigmatic. It initiates the innate immune response against gram-negative bacteria; and TLR4 polymorphisms, as ASP299GLY, suggested to attenuate receptor signaling, have been described. We demonstrated that TLR4 ASP299GLY polymorphism shows a significantly lower frequency in patients affected by myocardial infarction compared to controls, whereas centenarians show a higher frequency. Thus, people genetically predisposed to developing weak inflammatory activity, seem to have fewer chances of developing cardio…

A study of age-related IgE pathophysiological changes.

Abstract The literature on immunosenescence has focused mainly on T cell impairment. However, it is well known that B function is also profoundly affected. In particular, several studies have shown age-related changes in immunoglobulin serum levels. Concerning allergic diseases, the incidence of onset of allergic symptoms, as well as their severity, seems to decrease with age. So, the decline of onset of allergic symptoms observed in ageing might result from a decrease of serum total IgE due to an unbalance of cytokines and soluble factors involved in its production. To gain insight into the mechanisms of age related incidence of onset of allergic symptoms, as well as their severity, in thi…

Association between the polymorphisms of TLR4 and CD14 genes and Alzheimer's disease.

Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease which in Western society mainly accounts for clinical dementia. Inflammation plays a key role in AD and dissecting the genetics of inflammation may provide an answer to the possible treatment. Hence, the better understanding of different molecular and cellular inflammatory mechanisms is crucial for complete knowledge of AD pathophysiology, and for its prevention and drug therapy. Accordingly, in the present study we evaluated whether the pro-inflammatory polymorphisms of lipopolysaccaride-receptors, +896A/G Toll-Like Receptor (TLR4) and -260C/T CD14, are risk factors for AD. The study included both 626 AD …

Biology of Longevity: Role of the Innate Immune System

Genetic factors play a relevant role in the attainment of longevity because they are involved in cell maintenance systems, including the immune system. In fact, longevity may be correlated with optimal functioning of clonotypic and natural immunity. The aging of the immune system, known as immunosenescence, is the consequence of the continuous attrition caused by chronic antigenic overload. The antigenic load results in the progressive generation of inflammatory responses involved in age-related diseases. Most of the parameters influencing immunosenescence appear to be under genetic control, and immunosenescence fits with the basic assumptions of evolutionary theories of aging, such as anta…

Role of TLR4 polymorphisms in inflammatory responses: implications for unsuccessful aging.

The total burden of infection at various sites may affect the progression of atherosclerosis and Alzheimer's disease (AD), the risk being modulated by host genotype. The role of lipopolysaccharide (LPS) receptor TLR4 is paradigmatic. It initiates the innate immune response against gram-negative bacteria, and TLR4 single nucleotide polymorphisms (SNPs), such as +896A/G, known to attenuate receptor signaling, have been described. This SNP shows a significantly lower frequency in patients affected by myocardial infarction or AD. Thus, people genetically predisposed to developing lower inflammatory activity seem to have less chance of developing cardiovascular disease (CVD) or AD. In the presen…

Genetics of longevity. Data from the studies on Sicilian centenarians

Abstract The demographic and social changes of the past decades have determined improvements in public health and longevity. So, the number of centenarians is increasing as a worldwide phenomenon. Scientists have focused their attention on centenarians as optimal model to address the biological mechanisms of "successful and unsuccessful ageing". They are equipped to reach the extreme limits of human life span and, most importantly, to show relatively good health, being able to perform their routine daily life and to escape fatal age-related diseases, such as cardiovascular diseases and cancer. Thus, particular attention has been centered on their genetic background and immune system. In thi…

Association between C1019T polymorphism of connexin37 and acute myocardial infarction: a study in patients from Sicily

Abstract During atherogenesis, a critical role is played by intercellular communication via gap junctions, cell membrane channels linking the cytoplasmic compartments of adjacent cells. The component protein subunits of these channels, called connexin (Cx), belong to a multigene family. Cx37 is involved in growth, regeneration after injury and ageing of the endothelial cells, suggesting its role in atherosclerosis. The C1019 single nucleotide polymorphism (SNP) of Cx37 gene was associated with thickening of the carotid intima in Swedish men and was also associated with coronary artery disease in a Taiwanese population. On the other hand, in two more recent studies performed in male Japanese…

Opposite Role of Pro-Inflammatory Alleles in Acute Myocardial Infarction and Longevity: Results of Studies Performed in a Sicilian Population

The major trait characterizing offspring in centenarians is a reduction in the prevalence of cardiovascular disease. Because a pro-inflammatory genotype seems to contribute significantly to the risk of coronary heart disease, alleles associated with disease susceptibility would not be included in the genetic background favoring longevity, as suggested by our previous studies on inflammatory cytokines. To confirm whether genotypes of inflammatory molecules play an opposite role in atherosclerosis and longevity, we are studying the role of other proinflammatory alleles, such as pyrin and CCR5, in acute myocardial infarction and longevity. The results support the hypothesis that the genetic ba…

Connexin37 1019 gene polymorphism in myocardial infarction patients and centenarians

Interleukin-5 production by mononuclear cells from aged individuals: implication for autoimmunity.

It is well known that in the elderly a deterioration of immune functions may occur. Particularly, stimulation of T cells from aged individuals leads to different kind and/or size of responses if compared with the responses obtained from T cells from young individuals. At the same time, an increase in prevalence of autoantibodies occurs in elderly. The altered production of certain cytokines might explain this paradox of decreased responsiveness to foreign antigens in the face of an increased response to self-antigens. We and others have suggested that this kind of immune response might depend on an age-associated impairment of Th-1 type function that selectively affects production of cytoki…

Pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype: a genetically determined defect of C4 influences immunological parameters of healthy carriers of the haplotype.

Abstract Subjects with certain HLA alleles have a higher risk of specific autoimmune diseases than those without these alleles. The 8.1 ancestral haplotype (AH) is a common Caucasoid haplotype carried by most people who type for HLA-B8,DR3. It is unique in its association with a wide range of immunopathological diseases. To gain insight into the identification of the mechanism(s) of disease susceptibility of 8.1 AH carriers, we have investigated the prevalence of circulating immune complexes and non-organ-specific autoantibodies in healthy carriers of the haplotype. The results show that carriers of 8.1 AH display both a significant increased prevalence of immune complexes and higher titers…

PECAM-1/CD31 in infarction and longevity.

: Inflammation has recently proven to be associated with the pathogenesis of atherosclerosis and inflammatory genes are good candidates for the risk of developing atherosclerosis. The early phase of atherosclerosis involves the recruitment of inflammatory cells from the circulation and their transendothelial migration. This process is mainly mediated by cellular adhesion molecules, which are expressed by the vascular endothelium and by circulating leukocytes in response to several inflammatory stimuli. Adhesion of circulating cells to the arterial surface is among the first detectable events in atherogenesis. Cellular adhesion molecules, expressed by the vascular endothelium and by circulat…

Interleukin-12 release by mitogen-stimulated mononuclear cells in the elderly.

Abstract Defects involving cellular expression of activation molecules, cell mediated immune response and natural killer (NK) activity are commonly observed in the elderly. Herein, data are reported on the evaluation of IL-12 production by old subjects. IL-12 is, actually, considered the key molecule for the induction of a T helper 1 (Th1) -type and NK response. IL-12 production from old subjects peripheral blood mononuclear cells (PBMNC) was evaluated using T-independent (bacterial lipopolysaccharide, LPS) or -dependent (phytoemagglutinin, PHA; immobilized anti-CD3 monoclonal antibodies, anti-CD3) mitogens. The IL-12 production after LPS stimulation was not reduced in cultures from old sub…

Inflammatory networks in ageing, age-related diseases and longevity

Inflammation is considered a response set by the tissues in response to injury elicited by trauma or infection. It is a complex network of molecular and cellular interactions that facilitates a return to physiological homeostasis and tissue repair. The individual response against infection and trauma is also determined by gene variability. Ageing is accompanied by chronic low-grade inflammation state clearly showed by 2-4-fold increase in serum levels of inflammatory mediators. A wide range of factors has been claimed to contribute to this state; however, the most important role seems to be played by the chronic antigenic stress, which affects immune system thorough out life with a progress…