Domenico Lio

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 progressive activation of macrophages and related cells. This pro-inflammatory status, interacting with the genetic background, potentially triggers the onset of age-related inflammatory diseases as atherosclerosis. Thus, the analysis of polymorphisms of the genes that are key nodes of the natural immunity response might clarify the patho-physiology of age-related inflammatory diseases as atherosclerosis. On the other hand, centenarians are characterized by marked delay or escape from age-associated diseases that, on average, cause mortality at earlier ages. In addition, centenarian offspring have increased likelihood of surviving to 100 years and show a reduced prevalence of age-associated diseases, as cardiovascular disease (CVD) and less prevalence of cardiovascular risk factors. So, genes involved in CVD may play an opposite role in human longevity. Thus, the model of centenarians can be used to understand the role of these genes in successful and unsuccessful ageing. Accordingly, we report the results of several studies in which the frequencies of pro-inflammatory alleles were significantly higher in patients affected by infarction and lower in centenarians whereas age-related controls displayed intermediate values. These findings point to a strong relationship between the genetics of inflammation, successful ageing and the control of cardiovascular disease at least in men, in which these studies were performed. These data are also briefly discussed in the light of antagonistic pleiotropy theory and in order to pursuit a pharmacogenomics approach.

Gender-specific association between -1082 IL-10 promoter polymorphism and longevity.

Ageing is characterized by a pro-inflammatory status, which could contribute to the onset of major age-related diseases. Thus, genetic variations in pro- or anti-inflammatory cytokines might influence successful ageing and longevity. IL-10 is an appropriate candidate because it exerts powerful inhibitory effects on pro-inflammatory function. IL-10 production is controlled by several polymorphic elements in the 5′ flanking region of IL-10 gene on 1q32 locus, involving alleles at two microsatellite regions and several polymorphisms in promoter region. We analysed in 190 Italian centenarians (>99 years old, 159 women and 31 men) and in 260 <60 years old control subjects (99 women and 161 men), matched for geographical distribution, genotype frequencies for −1082G→A, −819C→T and −592C→A IL-10 proximal promoter gene biallelic polymorphisms by sequence specific probes. −1082G homozygous genotype was increased in centenarian men (P < 0.025) but not in centenarian women. No difference was found between centenarians and control subjects regarding the other two polymorphisms. The presence of −1082GG genotype, suggested to be associated with high IL-10 production, significantly increases the possibility to reach the extreme limit of human lifespan in men. Together with previous data on other polymorphic loci (Tyrosine Hydroxylase, mitochondrial DNA, IL-6, haemochromatosis, IFN-γ), this finding points out that that gender is a major variable in the genetics of longevity, suggesting that men and women follow different strategies to reach longevity. Concerning the biological significance of this association, we have not searched for functional proves that IL-10 is involved. Thus, we should conclude that our data only suggest that a marker on 1q32 genomic region may be involved in successful ageing in man. However, recent data on IL-6 and IFN-γ genes suggest that longevity is negatively associated with genotypes coding for a pro-inflammatory profile. Thus, it is intriguing that the possession of −1082G genotype, suggested to be associated with IL-10 high production, is significantly increased in centenarians.

Role of TGF-β Pathway Polymorphisms in Sporadic Thoracic Aortic Aneurysm: rs900 TGF-β2 Is a Marker of Differential Gender Susceptibility

Thoracic aortic aneurysm (TAA) is a progressive disorder involving gradual dilation of ascending and/or descending thoracic aorta with dissection or rupture as complications. It occurs as sporadic or defined syndromes/familial forms.Genetic, molecular and cellular mechanims of sporadic TAA forms are poorly characterized and known. Thus, our interest has been focused on investigating the role of genetic variants of transforming growth factor-β (TGF-β) pathways in TAA risk. On the other hand, no data on the role of genetic variants of TGF-β pathway in sporadic TAA exist until now. In addition, other cytokines, including IL-10, orchestrate TAA pathophysiology. Their balance determines the ultimate fate of the aortic wall as healing atherosclerosis or aneurysm formation. Thus, in this paper it was analyzed the role of ten polymorphisms of genes encoding TGF-β isoforms and receptors, and IL-10 in sporadic TAA. Our study included cases affected by sporadic TAA and two control groups. The most relevant finding obtained allows us to propose that rs900 TGF-β2 SNP is associated with sporadic TAA in women. This might open new perspectives for the analysis of sporadic TAA susceptibility factors and prevention.

Pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype : effect of multiple gene interactions

Genetic studies have shown that individuals with certain HLA alleles have a higher risk of specific autoimmune disease than those without these alleles. Particularly, the association in all Caucasian populations of an impressive number of autoimmune diseases with genes from the HLA-B8,DR3 haplotype that is part of the ancestral haplotype (AH) 8.1 HLA-A1, Cw7, B8, TNFAB*a2b3, TNFN*S, C2*C, Bf*s, C4A*Q0, C4B*1, DRB1*0301, DRB3*0101, DQA1*0501, DQB1*0201 has been reported by different research groups. This haplotype, the more common one in northern Europe, is also associated in healthy subjects with a number of immune system dysfunctions. It has been proposed that a small number of genes within the 8.1 AH modify immune responsiveness and hence affect multiple immunopathological diseases. In this paper, the characteristic features of this haplotype that might give rise to these diverse conditions are reviewed, focusing on the role of multiple gene interactions in disease susceptibility of 8.1 AH.

Aging, longevity, inflammation, and cancer

Abstract: Cancer rates increase sharply with age in both sexes, and the majority of cases of cancer occur in patients over the age of 65 years. However, the incidence and mortality for cancer level off around 85‐90 years of age, followed by a plateau, or even a decline in the last decades of life. Therefore, it seems reasonable to conclude that centenarians are endowed with a peculiar resistance to cancer. Tumor progression is a complex process that depends on interactions between tumor and host cells. One aspect of the host response, the inflammatory response, is of particular interest because it includes the release of proinflammatory cytokines, some of which may promote tumor growth and hence influence survival. Data in the literature reviewed in this paper suggest that some kind of solid tumors are affected by regulatory cytokine genotypes. In particular proinflammatory genotypes characterized by a low IL‐10 producer or a high IL‐6 producer seem to be associated with a worse clinical outcome. On the other hand, recent evidence has linked IL‐10 and IL‐6 cytokine polymorphisms to longevity. In fact, those individuals who are genetically predisposed to produce high levels of IL‐6 have a reduced capacity to reach the extreme limits of human life, whereas the high IL‐10‐producer genotype is increased among centenarians. This opposite effect of IL‐6 and IL‐10 common gene polymorphisms in cancer and longevity is intriguing. These data prompt considerations of the role that antagonistic pleiotropy plays in disease and in longevity. Inflammatory genotypes may be both friends and enemies. In fact, they are an important and necessary part of the normal host responses to pathogens, but the overproduction of inflammatory cytokines might cause immune‐inflammatory diseases and eventually death. In fact, our immune system has evolved to control pathogens, so proinflammatory responses are likely to be evolutionarily programmed to resist fatal infections, and a high IL‐6 or a low IL‐10 production is associated with increased resistance to pathogens. However, decreased level of IL‐6 or increased level of IL‐10 might better control inflammatory responses and cancer development. These conditions might result in an increased chance of long‐life survival in an environment with a reduced antigen (i.e., pathogen) load.

Inflammation, genetics, and longevity: further studies on the protective effects in men of IL-10-1082 promoter SNP and its interaction with TNF-α -308 promoter SNP

Ageing is associated with chronic, low grade inflammatory activity leading to long term tissue damage, and systemic chronic inflammation has been found to be related to mortality risk from all causes in older persons.1 Also, the genetic constitution of the organism interacting with systemic inflammation may cause defined organ specific illnesses. Thus, age related diseases such as Alzheimer’s disease (AD), Parkinson’s disease, atherosclerosis, type 2 diabetes, sarcopenia, and osteoporosis, are initiated or worsened by systemic inflammation, suggesting the critical importance of unregulated systemic inflammation in the shortening of survival in humans.1–3 Accordingly, proinflammatory cytokines are believed to play a pathogenetic role in age related diseases, and genetic variations located within their promoter regions have been shown to influence the susceptibility to age related diseases, by increasing gene transcription and therefore cytokine production.3,4 Conversely, genetic variations determining increased production of anti-inflammatory cytokines or decreased production of proinflammatory cytokines have been shown to be associated with successful ageing, suggesting a role for the control of the inflammatory state in the attainment of longevity. As recently reported, the distribution of +874T→A interferon(IFN)-γ,5 −174C→G IL-6,6 and −1082G→A interleukin(IL)-107 single nucleotide polymorphisms (SNPs) has been shown to be different in centenarians than in younger people.5–7 The +874T allele, involved in high production of the proinflammatory cytokine IFN-γ, was found less frequently in centenarian women than in control women.5 Also, the proportion of subjects homozygous for the G allele at the −174 IL-6 locus, characterised by high serum levels of the proinflammatory cytokine IL-6, was significantly decreased in centenarian men.6 Conversely, the presence of the −1082 GG genotype, suggested to be associated with high production of the anti-inflammatory cytokine IL-10, was significantly increased in centenarian men in comparison with younger male subjects.7 These …

Interleukin-10 promoter polymorphism in sporadic Alzheimer's disease

Proinflammatory cytokines and acute-phase proteins play an important role in Alzheimers disease (AD) neurodegeneration, and common polymorphisms of genes controlling their high production have been shown to be associated with AD. Thus, AD patients display a proinflammatory genotype and the control of inflammation might play a protective role in AD development. By sequence-specific probes, we have evaluated the role of anti-inflammatory cytokine interleukin(IL)-10 in AD, by analysing in 132 AD patients and 213 healthy controls the prevalence of three different haplotypes, involving three single-nucleotide polymorphisms (SNPs) at −1082 (G→A), −819 (C→T) and −592 (C→A) nucleotides of IL-10 promoter, associated with different IL-10 production. The percentage of −1082A carrier subjects was significantly increased among AD patients, and this increase was mainly due to the increase of ATA haplotype. Analysing these results according to the well-known genetic risk factor APOE-e4 allele, no significant differences were observed in SNP IL-10 allele distribution between AD patients carrying the genotype or not. So we may conclude that the presence of −1082A allele and in particular of −1082A/−819T/−592A haplotype, associated with a low production of anti-inflammatory cytokine IL-10, may be considered as an additive and independent genetic risk factor for AD.

B cells in the aged: CD27, CD5, and CD40 expression.

Ageing is characterized by numerous changes in lymphocyte subpopulations. In the present paper we have focused on B cells carrying the surface markers CD27, CD5 and CD40. CD27 is considered a marker of primed (memory) cells and its engagement promotes the differentiation of memory B cells into plasma cells. CD5 is expressed on B1 cells, which are considered to be responsible for T cell-independent antibody production other than autoantibodies. The CD40 molecule binds CD40L (CD154) and is necessary for T-dependent antibody responses. Here we show that the absolute number of CD5+ and CD40+ B cells is decreased in the elderly, while CD27+ B lymphocytes only marginally decrease in centenarians. However, there is a decrease of the percentage of CD5+ B cells, an increase of CD27+ B cells, while CD40 does not change significantly. These data, together with the increased number of NK cells during aging, suggest different regulation of antibody production in the elderly which might be another example of immune remodeling with aging, based on interactions between human B and NK cells.

Opposite effects of interleukin 10 common gene polymorphisms in cardiovascular diseases and in successful ageing: genetic background of male centenarians is protective against coronary heart disease

Centenarians escape, or at least have a delay in, age associated diseases that normally cause mortality at earlier ages. Considerable evidence supports the involvement of genetic components to longevity. Accordingly, the siblings of centenarians have a markedly increased probability of living to 100 years of age. A recent study showed that the offspring of centenarians had a markedly reduced prevalence of age associated diseases, particularly cardiovascular disease and cardiovascular risk factors. On the other hand, this is not unexpected in view of the fact that cardiovascular diseases account for about 50% of all deaths worldwide.1–3 ### Key points

Are Endothelial Progenitor Cells the Real Solution for Cardiovascular Diseases? Focus on Controversies and Perspectives.

Advanced knowledge in the field of stem cell biology and their ability to provide a cue for counteracting several diseases are leading numerous researchers to focus their attention on “regenerative medicine” as possible solutions for cardiovascular diseases (CVDs). However, the lack of consistent evidence in this arena has hampered the clinical application. The same condition affects the research on endothelial progenitor cells (EPCs), creating more confusion than comprehension. In this review, this aspect is discussed with particular emphasis. In particular, we describe biology and physiology of EPCs, outline their clinical relevance as both new predictive, diagnostic, and prognostic CVD biomarkers and therapeutic agents, discuss advantages, disadvantages, and conflicting data about their use as possible solutions for vascular impairment and clinical applications, and finally underline a very crucial aspect of EPCs “characterization and definition,” which seems to be the real cause of large heterogeneity existing in literature data on this topic.