RESUMEN
This study assessed the diversity and composition of bacterial communities within soils and lake sediments from an Arctic lake area (London Island, Svalbard). A total of 2,987 operational taxonomic units were identified by high-throughput sequencing, targeting bacterial 16S rRNA gene. The samples from four sites (three samples in each site) were significantly different in geochemical properties and bacterial community composition. Proteobacteria and Acidobacteria were abundant phyla in the nine soil samples, whereas Proteobacteria and Bacteroidetes were abundant phyla in the three sediment samples. Furthermore, Actinobacteria, Chlorobi, Chloroflexi, Elusimicrobia, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria significantly varied in their abundance among the four sampling sites. Additionally, members of the dominant genera, such as Clostridium, Luteolibacter, Methylibium, Rhodococcus, and Rhodoplanes, were significantly different in their abundance among the four sampling sites. Besides, distance-based redundancy analysis revealed that pH (p < 0.001), water content (p < 0.01), ammonium nitrogen ([Formula: see text]-N, p < 0.01), silicate silicon ([Formula: see text]-Si, p < 0.01), nitrite nitrogen ([Formula: see text]-N, p < 0.05), organic carbon (p < 0.05), and organic nitrogen (p < 0.05) were the most significant factors that correlated with the bacterial community composition. The results suggest soils and sediments from a lake area in the Arctic harbor a high diversity of bacterial communities, which are influenced by many geochemical factors of Arctic environments.
RESUMEN
Aging is acommon, progressive and irreversible state of multi-cell dysfunction. Immune aging mainly includes the declines of regenerative capacity and lymphoid lineage differentiation potential, the hyporesponsive to infection and vaccination, the hyperresponsive in the context of inflammatory pathology, and the increased risk of autoimmunity. The dysfunction of aged immune system accelerates the occurrence of aging and age-related diseases. The mutation of immunity genes that affect immune responses accelerates or slows aging process and age-related diseases. The frequencies of acquired immunity genes, such as immune protective HLA II DRB1*11 and DRB*16-associated haplotype, are increased in the longevity populations. The increased susceptibility of immune inflammatory response, morbidity and mortality in the elderly is often associated with decreased frequencies of anti-inflammatory factor IL-10 -1082G allele, TNF-ß1 haplotype cnd10T/C, cnd25G/G, -988C/C, -800G/A, low proinflammatory fator TNFa level related extended TNF-A genotype -1031C/C, -863C/A, -857C/C, IL-6-174 CC and IFN-γ+874 T allele as well. The innate immunity genes, such as highly expressed anti-inflammatory +896 G KIR4 allele, CCR5Δ32 variant, -765 C Cox-2 allele, -1708 G and 21 C 5-Lox alleles are detected in centenarians. In age-related diseases, a higher CMV-specific IgG antibody level in elderly individuals is associated with a decreased frequency of KIR haplotypes KIR2DS5 and A1B10 and an increased frequency of MBL2 haplotypes LYPB, LYQC and HYPD that result in the absence of MBL2 protein. The increased frequencies of CRP ATG haplotypes and CFH 402 His allele indicate high mortality in the elderly. In the present study, we review the advances in the polymorphism and haplotype of innate and adoptive immunity genes, and their association with both aging and age-related diseases. To strengthen the analysis of extended haplotypes, epigenetic studies of immunity genes and genetic study of hematopoietic stem cell senescence will be helpful to understand the accurate basis of aging-related immune genetics better.
Asunto(s)
Envejecimiento/genética , Inmunidad , Polimorfismo Genético , Anciano , Anciano de 80 o más Años , Envejecimiento/inmunología , Femenino , Antígenos HLA-DR/genética , Antígenos HLA-DR/inmunología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The lifelong exposure of antigens and stressors results in chronic oxidative stress situation in the organism. The free radicals and reactive oxygen species (ROS) with high reactivity produced by our cells under oxidative stress will cause oxidative damage in biomolecules. The oxidative damage leads to the releases of both damage-associated-molecular patterns (DAMPs) and intracellular cytokines. DAMPs activate pathogen recognition receptors (PRRs) and non-PRRs. Intracellular cytokines activate signalling pathways downstream of PRRs. Activation of these receptors results in the upregulation of cytokines and chemokines, which are released to recruit and activate additional inflammatory cells and cause the systemic and chronic sterile inflammation. The regulatory system, especially immune systems play an important role in homeostasis maintenance in the organism. The cells of immune systems are very vulnerable to oxidative damage. Once the homeostasis is destroyed, an imbalance between inflammatory and anti-inflammatory networks will occur. Genetic factor also is an important factor of oxi-inflamm-aging and age-related diseases. Many genes are involved in oxidative stress, inflammation process, and the genomic variations within most of these genes might produce different effects on oxi-inflamm-aging. The polymorphism of ApoE genes can affect the antioxidant and immunomodulatory/anti-inflammatory properties of the organism. ApoE genotype-phenotype is associated with the progress and prognosis of oxi-inflamm-aging, age-related diseases as well. Anti-inflammation together with regulation of the expression of ApoE might be an efficient method against oxi-inflamm-aging. Based on our previous studies, the progresses in these areas are reviewed.
Asunto(s)
Envejecimiento , Apolipoproteínas E/genética , Inflamación/genética , Estrés Oxidativo , Animales , Antioxidantes/metabolismo , Citocinas/metabolismo , Homeostasis , Humanos , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
Nonhuman primate rhesus monkey is a ideal model for human aging and aging intervention. Same with human aging, rehesus monkey demonstrates age-related aging and diseases in endocrine, neural, immune and cardiovascular system. Coloric restriction can slow down the primary and secondry aging efficently. The mechanism may be to suppress the oxidative stress-inflammaging-DNA damage by mediating the nutrient sensitive metablic signal pathways, and activate damaged DNA repair. However, the differeces of study design, husbandry and diet composition may differently affect CR against the the primary and secondry effects in a long-lived nonhuman primate. Optimization in protocol design, control of the experimetal variables, and shortening the experimental period will be advantageous to understand the mechanistic questions about the anti-aging effects of CR.