Dynamic alteration of soluble serum biomarkers in healthy aging

Cytokine atlas of the population-based cohort SHIP-TREND-0 - Associations with age, sex, and BMI

BACKGROUND

The characterization of physiological immune signatures in a population-based cohort is a prerequisite for identifying pathological immune signatures associated with inflammatory or autoimmune diseases.

METHODS

Here, 47 plasma cytokines, chemokines, and growth factors were quantified with a bead-based multiplex-assay (Merck HCYTA-60 K) using a FLEXMAP 3D™ instrument in 1175 individuals of the Study of Health in Pomerania (SHIP; TREND cohort, 532 men and 643 women, age: 20 to 81, BMI: 17.7 to 53.6). Associations of cytokine concentrations with age, sex, BMI, season, and blood cell parameters (BCP) were examined by multivariate regression models.

RESULTS

The physiological cytokine concentrations differed strongly between analytes, with median concentrations ranging from 0.6 to 7820 pg/mL. Many cytokine levels showed a large dynamic range within the study population. Higher levels of the pro-inflammatory cytokines and chemokines IL-6, IL-8, CXCL9, CXCL10, IL-12p40, CCL2, CCL4, CCL11, IL-27, FLT3LG, and TNFα were significantly associated with increasing age. The strongest age-associated effects were seen for CXCL9 (βst = 0.4, p < 0.001) and CXLC10 (βst = 0.3, p < 0.001). Significant sex differences were detected for CCL2, CCL3, CCL4, CCL11, CCL22, IL-12p40, IL-1RA, IL-18, IL-27, and TNFα levels among which CCL11 showed the strongest effect (βst = -0.24, p < 0.001) with a lower level in women compared to men. Moreover, seven cytokines and chemokines, i.e. CCL4, CCL22, CXCL10, IL-1RA, IL-18, IL-6, and TNFα, displayed higher levels with increasing BMI. Among those, the strongest effect was seen for IL-1RA (βst = 0.19, p < 0.001), CCL4 (βst = 0.16, p < 0.001) and CXCL10 (βst = 0.14, p < 0.001). Only CCL11 (βst = -0.17, p < 0.001) decreased with increasing BMI. Subjects categorized as obese exhibited significantly elevated levels of CCL4, CCL22, CXCL10, and IL-1RA, while only CCL11 showed significantly reduced levels compared to normal weight. Certain cytokines such as IL-6, IL-18, or TNFα showed decreased significance levels after adjustment for blood cell components indicating blood cell components (BCPs) as potential confounders. We observed no significant non-linear seasonal effects for the investigated cytokines.

CONCLUSION

The generated cytokine atlas provides detailed information on cytokine variations in the general population and will provide a reference base for disease-related studies in the future. Furthermore, BCPs should be considered as potential confounders in association studies based on plasma cytokine levels.

Causal effects of circulating inflammatory proteins on knee and hip osteoarthritis: A two sample Mendelian randomization study

INTRODUCTION

Numerous circulating proteins are linked to the presence or severity of joint inflammation. However, traditional studies could not explain whether these protein biomarkers are proximate to disease progression.

METHOD

We conducted a study to explore the causal effects of 91 circulating inflammation-related proteins (CIPs) on knee osteoarthritis (KOA) and hip osteoarthritis (HOA), using two-sample Mendelian randomization (MR). The primary analysis utilized the inverse variance weighted (IVW) method, augmented by complementary approaches including weighted median, weighted mode, simple median, MR-Egger, and MR-PRESSO analysis. Sensitivity analysis validated the robustness of the results and ensured the absence of heterogeneity and horizontal pleiotropy.

RESULTS

We identified 2 CIPs with a causal effect on KOA, including CXCL9 (OR = 1.249, 95% CI = 1.046-1.492, P = 0.014) and TNF-β (OR = 1.105, 95% CI = 1.014-1.204, P = 0.023). Additionally, 3 CIPs were found to have a causal effect on HOA, including CXCL6 (OR = 1.058, 95% CI = 1.004-1.116, P = 0.035), RANKL (OR = 1.067, 95% CI = 1.002-1.137, P = 0.044), and VEGFA (OR = 1.072, 95% CI = 1.008-1.140, P = 0.027).

CONCLUSIONS

In the current study, our findings indicated that CXCL9 and TNF-β had the potential to influence the risk of KOA, while CXCL6, RANKL, and VEGFA could impact the risk of HOA. These discoveries underscored the significance of these proteins as potential targets for intervention in the prevention and treatment of KOA and HOA. Key Points • We presented genetic evidence supporting a causal link between circulating inflammatory proteins associated with joint inflammation using MR methods. • 5 CIPs have demonstrated promotive effects on the occurrence of KOA and HOA.

Elucidating the role of chemokines in inflammaging associated atherosclerotic cardiovascular diseases

Age-related inflammation or inflammaging is a critical deciding factor of physiological homeostasis during aging. Cardiovascular diseases (CVDs) are exquisitely associated with aging and inflammation and are one of the leading causes of high mortality in the elderly population. Inflammaging comprises dysregulation of crosstalk between the vascular and cardiac tissues that deteriorates the vasculature network leading to development of atherosclerosis and atherosclerotic-associated CVDs in elderly populations. Leukocyte differentiation, migration and recruitment holds a crucial position in both inflammaging and atherosclerotic CVDs through relaying the activity of an intricate network of inflammation-associated protein-protein interactions. Among these interactions, small immunoproteins such as chemokines play a major role in the progression of inflammaging and atherosclerosis. Chemokines are actively involved in lymphocyte migration and severe inflammatory response at the site of injury. They relay their functions via chemokine-G protein-coupled receptors-glycosaminoglycan signaling axis and is a principal part for the detection of age-related atherosclerosis and related CVDs. This review focuses on highlighting the detailed intricacies of the effects of chemokine-receptor interaction and chemokine oligomerization on lymphocyte recruitment and its evident role in clinical manifestations of atherosclerosis and related CVDs. Further, the role of chemokine mediated signaling for formulating next-generation therapeutics against atherosclerosis has also been discussed.

Physical Interventions Restore Physical Frailty and the Expression of CXCL-10 and IL-1β Inflammatory Biomarkers in Old Individuals and Mice

BACKGROUND

Frailty is a geriatric syndrome associated with negative health outcomes that represents a dynamic condition with a potential of reversibility after physical exercise interventions. Typically, inflammatory and senescence markers are increased in frail individuals. However, the impact that physical exercise exerts on inflammatory and senescence biomarkers remains unknown. We assessed the effect of physical intervention in old individuals and mice and determined the expression of inflammatory and senescence markers.

METHODS

Twelve elderly individuals were enrolled from a primary care setting to a 3-month intervention. Frailty was measured by SPPB and the expression of biomarkers by cytokine array and RT-qPCR. In addition, 12 aged C57BL/6 mice completed an intervention, and inflammation and senescence markers were studied.

RESULTS

The physical intervention improved the SPPB score, reducing frail and pre-frail individuals. This was correlated with a reduction in several pro-inflammatory biomarkers such as IL-6, CXCL-1, CXCL-10, IL-1β, IL-7, GM-CSF as well as p16INK4a and p21CIP1 senescence markers. Otherwise, the levels of anti-inflammatory biomarker IL-4 were significantly increased. Moreover, the physical intervention in mice also improved their functional capacity and restored the expression of inflammatory (Il-1β, Cxcl-10, Il-6, and Cxcl-1) and senescence (p21Cip1) markers. Additionally, PLSDA and ROC curve analysis revealed CXCL-10 and IL-1β to be the biomarkers of functional improvement in both cohorts.

CONCLUSIONS

Our results showed that a physical intervention improves physical frailty, and reverses inflammation and senescence biomarkers comprising CXCL-10 and IL-1β.

Modulation of bone marrow and peripheral blood cytokine levels by age and clonal hematopoiesis in healthy individuals

Aging is associated with bone marrow (BM) inflammaging and, in some individuals, with the onset of clonal hematopoiesis (CH) of indeterminate potential. In this study conducted on 94 strictly healthy volunteers (18 to 80 yo), we measured BM and peripheral blood (PB) plasma levels of 49 hematopoietic and inflammatory cytokines. With aging, 7 cytokines increased in BM (FLT3L, CXCL9, HGF, FGF-2, CCL27, IL-16, IL-18) and 8 decreased (G-CSF, TNF, IL-2, IL-15, IL-17A, CCL7, IL-4, IL-10). In PB, 10 cytokines increased with age (CXCL9, FLT3L, CCL27, CXCL10, HGF, CCL11, IL-16, IL-6, IL-1 beta, CCL2). CH was associated with higher BM levels of MIF and IL-1 beta, lower BM levels of IL-9 and IL-5 and higher PB levels of IL-15, VEGF-A, IL-2, CXCL8, CXCL1 and G-CSF. These reference values provide a useful tool to investigate anomalies related to inflammaging and potentially leading to the onset of age-related myeloid malignancies or inflammatory conditions.

Differences in Circulating Extracellular Vesicle and Soluble Cytokines in Older Versus Younger Breast Cancer Patients With Distinct Symptom Profiles

Because extracellular vesicle (EV)-associated cytokines, both encapsulated and surface bound, have been associated with symptom severity, and may vary over the lifespan, they may be potential biomarkers to uncover underlying mechanisms of various conditions. This study evaluated the associations of soluble and EV-associated cytokine concentrations with distinct symptom profiles reported by 290 women with breast cancer prior to surgery. Patients were classified into older (≥60 years, n = 93) and younger (< 60 years, n = 197) cohorts within two previously identified distinct symptom severity profiles, that included pain, depressive symptoms, sleep disturbance, and fatigue (i.e., High Fatigue Low Pain and All Low). EVs were extracted using ExoQuick. Cytokine concentrations were determined using Luminex multiplex assay. Mann Whitney U test evaluated the differences in EV and soluble cytokine levels between symptom classes and between and within the older and younger cohorts adjusting for Karnofsky Performance Status (KPS) score, body mass index (BMI), and stage of disease. Partial correlation analyses were run between symptom severity scores and cytokine concentrations. Results of this study suggest that levels of cytokine concentrations differ between EV and soluble fractions. Several EV and soluble pro-inflammatory cytokines had positive associations with depressive symptoms and fatigue within both age cohorts and symptom profiles. In addition, in the older cohort with High Fatigue Low Pain symptom profile, EV GM-CSF concentrations were higher compared to the All Low symptom profile (p < 0.05). Albeit limited by a small sample size, these exploratory analyses provide new information on the association between cytokines and symptom profiles of older and younger cohorts. Of note, unique EV-associated cytokines were found in older patients and in specific symptom classes. These results suggest that EVs may be potential biomarker discovery tools. Understanding the mechanisms that underlie distinct symptom class profiles categorized by age may inform intervention trials and offer precision medicine approaches.

Cytokines in the Brain and Neuroinflammation: We Didn’t Starve the Fire!

In spite of the brain-protecting tissues of the skull, meninges, and blood-brain barrier, some forms of injury to or infection of the CNS can give rise to cerebral cytokine production and action and result in drastic changes in brain function and behavior. Interestingly, peripheral infection-induced systemic inflammation can also be accompanied by increased cerebral cytokine production. Furthermore, it has been recently proposed that some forms of psychological stress may have similar CNS effects. Different conditions of cerebral cytokine production and action will be reviewed here against the background of neuroinflammation. Within this context, it is important to both deepen our understanding along already taken paths as well as to explore new ways in which neural functioning can be modified by cytokines. This, in turn, should enable us to put forward different modes of cerebral cytokine production and action in relation to distinct forms of neuroinflammation.

EGFR-mediated epidermal stem cell motility drives skin regeneration through COL17A1 proteolysis

Skin regenerative capacity declines with age, but the underlying mechanisms are largely unknown. Here we demonstrate a functional link between epidermal growth factor receptor (EGFR) signaling and type XVII collagen (COL17A1) proteolysis on age-associated alteration of keratinocyte stem cell dynamics in skin regeneration. Live-imaging and computer simulation experiments predicted that human keratinocyte stem cell motility is coupled with self-renewal and epidermal regeneration. Receptor tyrosine kinase array identified the age-associated decline of EGFR signaling in mouse skin wound healing. Culture experiments proved that EGFR activation drives human keratinocyte stem cell motility with increase of COL17A1 by inhibiting its proteolysis through the secretion of tissue inhibitor of metalloproteinases 1 (TIMP1). Intriguingly, COL17A1 directly regulated keratinocyte stem cell motility and collective cell migration by coordinating actin and keratin filament networks. We conclude that EGFR-COL17A1 axis-mediated keratinocyte stem cell motility drives epidermal regeneration, which provides a novel therapeutic approach for age-associated impaired skin regeneration.

An inflammatory aging clock (iAge) based on deep learning tracks multimorbidity, immunosenescence, frailty and cardiovascular aging

While many diseases of aging have been linked to the immunological system, immune metrics capable of identifying the most at-risk individuals are lacking. From the blood immunome of 1,001 individuals aged 8-96 years, we developed a deep-learning method based on patterns of systemic age-related inflammation. The resulting inflammatory clock of aging (iAge) tracked with multimorbidity, immunosenescence, frailty and cardiovascular aging, and is also associated with exceptional longevity in centenarians. The strongest contributor to iAge was the chemokine CXCL9, which was involved in cardiac aging, adverse cardiac remodeling and poor vascular function. Furthermore, aging endothelial cells in human and mice show loss of function, cellular senescence and hallmark phenotypes of arterial stiffness, all of which are reversed by silencing CXCL9. In conclusion, we identify a key role of CXCL9 in age-related chronic inflammation and derive a metric for multimorbidity that can be utilized for the early detection of age-related clinical phenotypes.

The age again in the eye of the COVID-19 storm: evidence-based decision making

BACKGROUND

One hundred fifty million contagions, more than 3 million deaths and little more than 1 year of COVID-19 have changed our lives and our health management systems forever. Ageing is known to be one of the significant determinants for COVID-19 severity. Two main reasons underlie this: immunosenescence and age correlation with main COVID-19 comorbidities such as hypertension or dyslipidaemia. This study has two aims. The first is to obtain cut-off points for laboratory parameters that can help us in clinical decision-making. The second one is to analyse the effect of pandemic lockdown on epidemiological, clinical, and laboratory parameters concerning the severity of the COVID-19. For these purposes, 257 of SARSCoV2 inpatients during pandemic confinement were included in this study. Moreover, 584 case records from a previously analysed series, were compared with the present study data.

RESULTS

Concerning the characteristics of lockdown series, mild cases accounted for 14.4, 54.1% were moderate and 31.5%, severe. There were 32.5% of home contagions, 26.3% community transmissions, 22.5% nursing home contagions, and 8.8% corresponding to frontline worker contagions regarding epidemiological features. Age > 60 and male sex are hereby confirmed as severity determinants. Equally, higher severity was significantly associated with higher IL6, CRP, ferritin, LDH, and leukocyte counts, and a lower percentage of lymphocyte, CD4 and CD8 count. Comparing this cohort with a previous 584-cases series, mild cases were less than those analysed in the first moment of the pandemic and dyslipidaemia became more frequent than before. IL-6, CRP and LDH values above 69 pg/mL, 97 mg/L and 328 U/L respectively, as well as a CD4 T-cell count below 535 cells/μL, were the best cut-offs predicting severity since these parameters offered reliable areas under the curve.

CONCLUSION

Age and sex together with selected laboratory parameters on admission can help us predict COVID-19 severity and, therefore, make clinical and resource management decisions. Demographic features associated with lockdown might affect the homogeneity of the data and the robustness of the results.

Inflammatory markers associated with fall recurrence and severity: The Bambuí Cohort Study of Aging

BACKGROUND

The aim of this study was to analyze the association between inflammatory markers and recurrent and severe falls in 1304 community-dwelling older adults from the Bambuí Cohort Study of Aging.

METHODS

Information about falls in the previous 12 months was collected, and classified based on recurrence (two or more falls) and severity (requirement of medical attention). The screened biomarkers included interleukins (IL-1β, IL-6, IL-10, and IL-12, TNF), chemokines (CXCL8, CXCL9, CXCL10, CCL2, and CCL5), and high-sensitive C-reactive protein (hs-PCR). Potential confounders included sociodemographic, behavioral, and health indicators. Associations were evaluated through logistic regression, using odds ratios (OR) and 95% confidence intervals (95% CI), with Stata 13.1.

RESULTS

The prevalence of recurrent and severe falls was 10.7% and 9.0%, respectively. After adjustments, elevated levels of IL-12 (OR: 1.92; 95% CI: 1.09-3.37) and CXCL9 (OR: 1.67; 95% CI: 1.05-2.66) were found to be associated with recurrent falls, while elevated levels of TNF (OR: 1.58; 95% CI: 1.01-2.50), IL-12 (OR: 2.04; 95% CI: 1.13-3.70), CXCL10 (OR: 1.75; 95% CI: 1.04-2.92), and CCL5 (OR: 1.90; 95% CI: 1.18-3.07) were associated with severe falls.

CONCLUSIONS

The results highlight a wide range of biomarkers not yet explored in the literature and suggest that inflammation may be an important component of recurrent and severe falls.

Premature cell senescence in human skin: Dual face in chronic acquired pigmentary disorders

Although senescence was originally described as an in vitro acquired cellular characteristic, it was recently recognized that senescence is physiologically and pathologically involved in aging and age-related diseases in vivo. The definition of cellular senescence has expanded to include the growth arrest caused by various cellular stresses, including DNA damage, inadequate mitochondria function, activated oncogene or tumor suppressor genes and oxidative stress. While senescence in normal aging involves various tissues over time and contributes to a decline in tissue function even with healthy aging, disease-induced premature senescence may be restricted to one or a few organs triggering a prolonged and more intense rate of accumulation of senescent cells than in normal aging. Organ-specific high senescence rate could lead to chronic diseases, especially in post-mitotic rich tissue. Recently, two opposite acquired pathological conditions related to skin pigmentation were described to be associated with premature senescence: vitiligo and melasma. In both cases, it was demonstrated that pathological dysfunctions are not restricted to melanocytes, the cell type responsible for melanin production and transport to surrounding keratinocytes. Similar to physiological melanogenesis, dermal and epidermal cells contribute directly and indirectly to deregulate skin pigmentation as a result of complex intercellular communication. Thus, despite senescence usually being reported as a uniform phenotype sharing the expression of characteristic markers, skin senescence involving mainly the dermal compartment and its paracrine function could be associated with the disappearance of melanocytes in vitiligo lesions and with the exacerbated activity of melanocytes in the hyperpigmentation spots of melasma. This suggests that the difference may arise in melanocyte intrinsic differences and/or in highly defined microenvironment peculiarities poorly explored at the current state of the art. A similar dualistic phenotype has been attributed to intratumoral stromal cells as cancer-associated fibroblasts presenting a senescent-like phenotype which influence the behavior of neoplastic cells in either a tumor-promoting or tumor-inhibiting manner. Here, we present a framework dissecting senescent-related molecular alterations shared by vitiligo and melasma patients and we also discuss disease-specific differences representing new challenges for treatment.

Circulating Cytokines and Lower Body Muscle Performance in Older Adults at Hospital Admission

BACKGROUND

Aging-related traits, including gradual loss of skeletal muscle mass and chronic inflammation, are linked to altered body composition and impaired physical functionality, which are important contributing factors to the disabling process. We sought to explore the potential relationship between lower-body muscle strength decline and inflammatory mediators in older adults.

METHODS

We performed a cross-sectional analysis in 38 older adults admitted to an acute care of the elderly unit (57.9% women, mean age=87.9±4.9 years; mean body mass index [BMI]=26.5±4.7 kg/m2). Clinical and functional outcomes including weight, height, BMI, dependence, physical and cognitive performance, and muscle strength measured by one-repetition maximum (1RM) for leg-extension, leg-press, chest-press and handgrip strength, were assessed. Blood serum content of 59 cytokines, chemokines and growth factors was assessed by protein arrays. Multivariate linear regression analyses were used to examine the relationship between cytokine concentrations and muscle strength parameters.

RESULTS

After controlling for confounding factors (age, sex, BMI, cumulative illness rating score and physical performance score), 1RM leg-press had a significant negative relationship with GRO (CXCL2) (β= -18.13, p=0.049), MIG (CXCL9) (β= -13.94, p=0.004), IGF-1 (β= -19.63, p=0.003), CK-BETA 8 (CCL23) (β= -28.31, p=0.018) and GCP-2 (CXCL6) (β= -25.78, p=0.004). Likewise, 1RM leg-extension had a significant negative relationship with IGFBP-1 (β= -11.49, p=0.023).

CONCLUSIONS

Thus, several serum cytokines/chemokines and growth factors are negatively associated with lower muscle strength in older patients. Further investigation is required to elucidate the mechanism of elevated inflammatory mediators leading to lower muscle strength.

Depression, GABA, and Age Correlate with Plasma Levels of Inflammatory Markers

Immunomodulation is increasingly being recognised as a part of mental diseases. Here, we examined whether levels of immunological protein markers changed with depression, age, or the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). An analysis of plasma samples from patients with a major depressive episode and control blood donors (CBD) revealed the expression of 67 inflammatory markers. Thirteen of these markers displayed augmented levels in patients compared to CBD. Twenty-one markers correlated with the age of the patients, whereas 10 markers correlated with the age of CBD. Interestingly, CST5 and CDCP1 showed the strongest correlation with age in the patients and CBD, respectively. IL-18 was the only marker that correlated with the MADRS-S scores of the patients. Neuronal growth factors (NGFs) were significantly enhanced in plasma from the patients, as was the average plasma GABA concentration. GABA modulated the release of seven cytokines in anti-CD3-stimulated peripheral blood mononuclear cells (PBMCs) from the patients. The study reveals significant changes in the plasma composition of small molecules during depression and identifies potential peripheral biomarkers of the disease.

Aging leads to dysfunctional innate immune responses to TLR2 and TLR4 agonists

BACKGROUND

Sepsis is more common in the elderly. TNF⍺ is recognized as an important mediator in sepsis and Toll-like receptors (TLRs) play an important role in initiating signaling cascades to produce TNF⍺. Little is known about how innate immunity is altered in healthy human aging that predisposes to sepsis.

AIMS AND METHODS

We tested the hypothesis that aging dysregulates the innate immune response to TLR 2 and 4 ligands. We performed whole blood assays on 554 healthy subjects aged 40-80 years. TNFα production was measured at baseline and after stimulation with the TLR2 agonists: peptidoglycan, lipoteichoic acid, Pam3CysK, Zymosan A and the TLR4 agonist lipopolysaccharide (LPS). In a subset of subjects (n = 250), we measured Toll-like receptor (TLR) 2, 4 and MyD88 expression using real-time PCR.

RESULTS AND DISCUSSION

We measured a 2.5% increase per year in basal secretion of TNFα with aging (n = 554 p = 0.02). Likewise, TNFα secretion was increased with aging after stimulation with peptidoglycan (1.3% increase/year; p = 0.0005) and zymosan A (1.1% increase/year p = 0.03). We also examined the difference between baseline and stimulated TNFα for each individual. We found that the increase was driven by the elevated baseline levels. In fact, there was a diminished stimulated response to LPS (1.9% decrease/year; p = 0.05), lipoteichoic acid (2.1% decrease/year p = 0.03), and Pam3CysK (2.6% decrease/year p = 0.0007). There were no differences in TLR or MyD88 mRNA expression with aging, however, there was an inverse relationship between TLR expression and stimulated TNFα production.

CONCLUSIONS

With aging, circulating leukocytes produce high levels of TNFα at baseline and have inadequate responses to TLR2 and TLR4 agonists. These defects likely contribute to the increased susceptibility to sepsis in older adults.

Inflammation as a mediator of arterial ageing

NEW FINDINGS

What is the topic of this review? This review summarizes and synthesizes what is known about the contribution of inflammation to age-related arterial dysfunction. What advances does it highlight? This review details observational evidence for the relationship of age-related inflammation and arterial dysfunction, insight from autoimmune inflammatory diseases and their effects on arterial function, interventional evidence linking inflammation and age-related arterial dysfunction, insight into age-related arterial inflammation from preclinical models and interventions to ameliorate age-related inflammation and arterial dysfunction.

ABSTRACT

Advanced age is a primary risk factor for cardiovascular disease, the leading cause of death in the industrialized world. Two major components of arterial ageing are stiffening of the large arteries and impaired endothelium-dependent dilatation in multiple vascular beds. These two alterations are major contributors to the development of overt cardiovascular disease. Increasing inflammation with advanced age is likely to play a role in this arterial dysfunction. The purpose of this review is to synthesize what is known about inflammation and its relationship to age-related arterial dysfunction. This review discusses both the initial observational evidence for the relationship of age-related inflammation and arterial dysfunction and the evidence that inflammatory autoimmune diseases are associated with a premature arterial ageing phenotype. We next discuss interventional and mechanistic evidence linking inflammation and age-related arterial dysfunction in older adults. We also attempt to summarize the relevant evidence from preclinical models. Lastly, we discuss interventions in both humans and animals that have been shown to ameliorate age-related arterial inflammation and dysfunction. The available evidence provides a strong basis for the role of inflammation in both large artery stiffening and impairment of endothelium-dependent dilatation; however, the specific inflammatory mediators, the initiating factors and the relative importance of the endothelium, smooth muscle cells, perivascular adipose tissue and immune cells in arterial inflammation are not well understood. With the expansion of the ageing population, ameliorating age-related arterial inflammation represents an important potential strategy for preserving vascular health in the elderly.

Young and Aged Blunt Trauma Patients Display Major Differences in Circulating Inflammatory Mediator Profiles after Severe Injury

BACKGROUND

Aging is accompanied by alterations in immune functions. How these changes translate into levels of circulating inflammatory mediators and network expression after severe trauma is not well characterized. To address this, we compared time-dependent changes in the levels of an extensive biomarker panel in cohorts of severely injured young and aged adults.

STUDY DESIGN

Cohorts of young (18 to 30 years old, n = 115) and aged (65 to 90 years old, n = 101) blunt trauma patients admitted to the ICU with plasma sampled 3 times within the first 24 hours and daily from day 1 to day 7 were assayed for 30 inflammatory biomarkers using Luminex analyzer. Stringently matched groups controlling for sex ratio and Injury Severity Score (n = 56 young vs n = 56 aged) were generated. Data were analyzed using 2-way ANOVA, area under the curve analysis, Dynamic Bayesian Network inference, and Dynamic Network Analysis.

RESULTS

In the overall cohorts, the young group had a significantly higher Injury Severity Score, which was associated with higher circulating levels of 18 inflammatory mediators from admission to day 7. The aged group had higher levels of C-X-C motif chemokine ligand 10/interferon gamma-induced protein 10 and C-X-C motif chemokine ligand 9/monokine induced by gamma interferon. In groups that were matched for Injury Severity Score, the significantly higher levels of interferon gamma-induced protein 10 and monokine induced by gamma interferon persisted in the aged. Dynamic Bayesian Network revealed interferon gamma-induced protein 10 and monokine induced by gamma interferon as key mediators in the aged, and Dynamic Network Analysis revealed higher network complexity in the aged.

CONCLUSIONS

These findings indicate that differences in the early inflammatory networks between young and aged trauma patients are not simply a suppression of pro-inflammatory responses in the aged, but are characterized by a major shift in the mediator profile patterns with high levels of CXC chemokines in the aged.

Towards frailty biomarkers: Candidates from genes and pathways regulated in aging and age-related diseases

OBJECTIVE

Use of the frailty index to measure an accumulation of deficits has been proven a valuable method for identifying elderly people at risk for increased vulnerability, disease, injury, and mortality. However, complementary molecular frailty biomarkers or ideally biomarker panels have not yet been identified. We conducted a systematic search to identify biomarker candidates for a frailty biomarker panel.

METHODS

Gene expression databases were searched (http://genomics.senescence.info/genes including GenAge, AnAge, LongevityMap, CellAge, DrugAge, Digital Aging Atlas) to identify genes regulated in aging, longevity, and age-related diseases with a focus on secreted factors or molecules detectable in body fluids as potential frailty biomarkers. Factors broadly expressed, related to several "hallmark of aging" pathways as well as used or predicted as biomarkers in other disease settings, particularly age-related pathologies, were identified. This set of biomarkers was further expanded according to the expertise and experience of the authors. In the next step, biomarkers were assigned to six "hallmark of aging" pathways, namely (1) inflammation, (2) mitochondria and apoptosis, (3) calcium homeostasis, (4) fibrosis, (5) NMJ (neuromuscular junction) and neurons, (6) cytoskeleton and hormones, or (7) other principles and an extensive literature search was performed for each candidate to explore their potential and priority as frailty biomarkers.

RESULTS

A total of 44 markers were evaluated in the seven categories listed above, and 19 were awarded a high priority score, 22 identified as medium priority and three were low priority. In each category high and medium priority markers were identified.

CONCLUSION

Biomarker panels for frailty would be of high value and better than single markers. Based on our search we would propose a core panel of frailty biomarkers consisting of (1) CXCL10 (C-X-C motif chemokine ligand 10), IL-6 (interleukin 6), CX3CL1 (C-X3-C motif chemokine ligand 1), (2) GDF15 (growth differentiation factor 15), FNDC5 (fibronectin type III domain containing 5), vimentin (VIM), (3) regucalcin (RGN/SMP30), calreticulin, (4) PLAU (plasminogen activator, urokinase), AGT (angiotensinogen), (5) BDNF (brain derived neurotrophic factor), progranulin (PGRN), (6) α-klotho (KL), FGF23 (fibroblast growth factor 23), FGF21, leptin (LEP), (7) miRNA (micro Ribonucleic acid) panel (to be further defined), AHCY (adenosylhomocysteinase) and KRT18 (keratin 18). An expanded panel would also include (1) pentraxin (PTX3), sVCAM/ICAM (soluble vascular cell adhesion molecule 1/Intercellular adhesion molecule 1), defensin α, (2) APP (amyloid beta precursor protein), LDH (lactate dehydrogenase), (3) S100B (S100 calcium binding protein B), (4) TGFβ (transforming growth factor beta), PAI-1 (plasminogen activator inhibitor 1), TGM2 (transglutaminase 2), (5) sRAGE (soluble receptor for advanced glycosylation end products), HMGB1 (high mobility group box 1), C3/C1Q (complement factor 3/1Q), ST2 (Interleukin 1 receptor like 1), agrin (AGRN), (6) IGF-1 (insulin-like growth factor 1), resistin (RETN), adiponectin (ADIPOQ), ghrelin (GHRL), growth hormone (GH), (7) microparticle panel (to be further defined), GpnmB (glycoprotein nonmetastatic melanoma protein B) and lactoferrin (LTF). We believe that these predicted panels need to be experimentally explored in animal models and frail cohorts in order to ascertain their diagnostic, prognostic and therapeutic potential.

Association between plasma CCL11 (eotaxin-1) and cognitive status in older adults: Differences between rural and urban dwellers

The chemokine CCL11 has been implicated in age-related cognitive deterioration in mice, yet evidence on the relationship between CCL11 and cognitive function in humans is limited. This study explored associations between CCL11 and cognition in rural and urban community-dwelling older adults. Participants were 515 urban dwellers from the 3C-Bordeaux cohort and 318 rural dwellers from the AMI cohort. Plasma CCL11 was measured using an enzyme-linked immunoassay. Mini Mental State Examination (MMSE) test scores were used as the main measure of cognitive performance. Multivariate regression analysis was used to evaluate the cross-sectional association between CCL11 and cognitive performance. CCL11 was significantly higher in rural dwellers compared to city dwellers (median [IQR]: 145 [115-201] pg/mL vs. 103 [85-129] pg/mL; p < 0.001). After adjustment for confounders, CCL11 was found to be negatively associated with cognitive performance in rural dwellers but not in city dwellers. These results suggest that CCL11 may be an independent determinant of cognitive function in older rural dwellers and that the residential environment modifies this association.

Cytokine profiles in the aqueous humor and serum of patients with dry and treated wet age-related macular degeneration

PURPOSE

To identify disease-specific cytokine profile differences in the aqueous humor (AH) (other than the vascular endothelial growth factor) between patients with dry and treated wet age-related macular degeneration (AMD) and healthy controls.

METHODS

This retrospective study drew on a case-series of patients diagnosed with dry AMD (n = 25) and treated wet AMD (n = 19), as well as on healthy controls (no systemic therapy; n = 20) undergoing phacoemulsification or vitrectomy. Samples of AH and serum were collected in parallel at the beginning of surgery. The levels of 43 cytokines were simultaneously determined using the Bio-Plex® multiplex beads system. Differences between the three groups were statistically compared using the Kruskal-Wallis H-Test after applying the Bonferroni correction for multiple comparisons (p<0.0012).

RESULTS

The concentrations of three cytokines were elevated in the AH of patients with dry AMD (CXCL6; p = 0.00067) and treated wet AMD (CXCL5, CXCL6, MIG/XCXL; all p<0.001) relative to those in the healthy controls. No other differences between the three groups were identified. The AH levels of seven cytokines (16%), including CXCL6, ranged below the lower limit of quantitation of the assay. Without the correction for multiple comparisons (p<0.05), the levels of 31 of the 43 cytokines in the AH of patients with AMD would have differed significantly from those in the control. The systemic cytokine profiles (serum) were similar in all three groups.

CONCLUSIONS

No systematic differences in the AH cytokine environment were identified between patients with dry AMD and those with treated wet AMD. This finding might indicate that AMD is either the result of a persistent imbalance in the physiological tissue milieu, or that the localized process induces no significant change in the cytokine environment of the anterior ocular segment.

A targeted proteomic assay for the measurement of plasma proteoforms related to human aging phenotypes

Circulating polypeptides and proteins have been implicated in reversing or accelerating aging phenotypes, including growth/differentiation factor 8 (GDF8), GDF11, eotaxin, and oxytocin. These proteoforms, which are defined as the protein products arising from a single gene due to alternative splicing and PTMs, have been challenging to study. Both GDF8 and GDF11 have known antagonists such as follistatin (FST), and WAP, Kazal, immunoglobulin, Kunitz, and NTR domain-containing proteins 1 and 2 (WFIKKN1, WFIKKN2). We developed a novel multiplexed SRM assay using LC-MS/MS to measure five proteins related to GDF8 and GDF11 signaling, and in addition, eotaxin, and oxytocin. Eighteen peptides consisting of 54 transitions were monitored and validated in pooled human plasma. In 24 adults, the mean (SD) concentrations (ng/mL) were as follows: GDF8 propeptide, 11.0 (2.4); GDF8 mature protein, 25.7 (8.0); GDF11 propeptide, 21.3 (10.9); GDF11 mature protein, 16.5 (12.4); FST, 29.8 (7.1); FST cleavage form FST303, 96.4 (69.2); WFIKKN1, 38.3 (8.3); WFIKKN2, 32.2 (10.5); oxytocin, 1.9 (0.9); and eotaxin, 2.3 (0.5). This novel multiplexed SRM assay should facilitate the study of the relationships of these proteoforms with major aging phenotypes.

Association of CCL11 promoter polymorphisms with schizophrenia in a Korean population

BACKGROUND

Immunological alterations and dysregulation of the inflammatory response have been suggested to play a crucial role in schizophrenia pathophysiology. Growing evidence supports the involvement of chemokines in brain development, thus many chemokines have been studied in relation with schizophrenia. The C-C motif chemokine ligand 11 (CCL11) has been shown to be related with synaptic plasticity and neurogenesis. Moreover, altered levels of CCL11 have been observed in schizophrenia patients. Therefore, we examined whether single nucleotide polymorphisms (SNPs) of the CCL11 in the promoter region contribute to susceptibility to schizophrenia.

METHODS

Four promoter SNPs [rs17809012 (-384T>C), rs16969415 (-426C>T), rs17735961 (-488C>A), and rs4795896 (576G>A)] were genotyped in 254 schizophrenia patients and 405 control subjects using Fluidigm SNPtype assays.

RESULTS

The genotype frequency of CCL11 rs4795896 (-576G>A) showed significant association with schizophrenia in a recessive model (AA vs. GG/AG, p < 0.0001) and in a log-additive model (AG vs. AA vs. GG, p < 0.0001). The allele frequency of rs4795896 also showed a significant association with schizophrenia (p < 0.0001). Furthermore, haplotype analysis revealed that GCT, ACT, and GCC haplotypes containing rs4795896, rs17735961 and rs17809012 were significantly associated with schizophrenia (p = 0.0044, p < 0.0001, and p < 0.0001, respectively).

CONCLUSION

Our results suggest that CCL11 promotor polymorphism is associated with increased risk for the development of schizophrenia in a Korean population.

Immune senescence and biomarkers profile of Bambuí aged population-based cohort

During immunosenescence many proinflammatory markers such as cytokines and chemokines are increased. This process called by Franceschi and colleagues as inflammaging is associated with chronic inflammation and the ethiology and pathophysiolgy of many ageing diseases as Alzheimer's and atherosclerosis. The knowledge of immune profile during ageing may provide some interventions that would improve the immune function in elderly and quality of life for old people. However, the identification of a group of potential biomarkers to monitor the ageing process is very difficult. In addition, most of the evidence evaluating immune biomarkers profile is based on data from older Caucasian adults. To our knowledge, no previous Latin American old population-based cohort has evaluated immunological parameters along the ageing process. The present work evaluated CXCL8, CXCL9, CXCL10, CCL2, CCL5, IL-1, IL-6, IL-12, TNF and IL-10 serum levels in 1494 older adults aged 60 to 95 from a population based ageing cohort in Brazil. Our data suggest that there is an increased positive predicted probability of participants to be a high producer of IL-6, CXCL8 and CXCL9. Moreover, results did not differ between men and women, except for CXCL10 that increased only in men. Results were not different in the adjusted model by many potential confounders, including African genomic ancestry. Together, these findings add novel insights about the immunologic aspects of ageing supported by a large population-based cohort study that provides evidences that corroborate with the inflammaging proposal and subsidize the establishment of biomarkers for monitoring the health status of aged population.

The systemic environment: at the interface of aging and adult neurogenesis

Aging results in impaired neurogenesis in the two neurogenic niches of the adult mammalian brain, the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle. While significant work has characterized intrinsic cellular changes that contribute to this decline, it is increasingly apparent that the systemic environment also represents a critical driver of brain aging. Indeed, emerging studies utilizing the model of heterochronic parabiosis have revealed that immune-related molecular and cellular changes in the aging systemic environment negatively regulate adult neurogenesis. Interestingly, these studies have also demonstrated that age-related decline in neurogenesis can be ameliorated by exposure to the young systemic environment. While this burgeoning field of research is increasingly garnering interest, as yet, the precise mechanisms driving either the pro-aging effects of aged blood or the rejuvenating effects of young blood remain to be thoroughly defined. Here, we review how age-related changes in blood, blood-borne factors, and peripheral immune cells contribute to the age-related decline in adult neurogenesis in the mammalian brain, and posit both direct neural stem cell and indirect neurogenic niche-mediated mechanisms.

Selected life-extending interventions reduce arterial CXCL10 and macrophage colony-stimulating factor in aged mouse arteries

Cardiovascular disease (CVD) is the leading cause of death in the industrialized world. Aging is the most predictive risk factor for CVD and is associated with arterial inflammation which contributes to increased CVD risk. Although age-related arterial inflammation has been described in both humans and animals, only a limited number of inflammatory mediators, cytokines and chemokines have been identified. In this investigation we sought to determine whether lifespan extending interventions, including crowded litter early life nutrient deprivation (CL), traditional lifelong caloric restriction (CR) and lifelong Rapamycin treatment (Rap) would attenuate age-related arterial inflammation using multi analyte profiling. Aortas from Young (4-6months), Old (22months), Old CL, Old CR and Old Rap mice were homogenized and cytokine concentrations were assessed using Luminex Multi Analyte Profiling. Chemokines involved in immune cell recruitment, such as CCL2, CXCL9, CXCL10, GMCSF and MCSF, were increased in Old vs. Young (p<0.05). The age-related increase of CXCL10 was prevented by CR (p<0.05 vs. Old). MSCF concentrations were lower in aortas of Rap treated mice (p<0.05 vs. Old). Interleukins (IL), IL-1α, IL-1β and IL-10, were also greater in Old vs. Young mice (p<0.05). These data demonstrate selected lifespan extending interventions can prevent or limit age-related increases in selected aortic chemokines.

The aging kidney and the nephrotoxic effects of mercury

Owing to advances in modern medicine, life expectancies are lengthening and leading to an increase in the population of older individuals. The aging process leads to significant alterations in many organ systems, with the kidney being particularly susceptible to age-related changes. Within the kidney, aging leads to ultrastructural changes such as glomerular and tubular hypertrophy, glomerulosclerosis, and tubulointerstitial fibrosis, which may compromise renal plasma flow (RPF) and glomerular filtration rate (GFR). These alterations may reduce the functional reserve of the kidneys, making them more susceptible to pathological events when challenged or stressed, such as following exposure to nephrotoxicants. An important and prevalent environmental toxicant that induces nephrotoxic effects is mercury (Hg). Since exposure of normal kidneys to mercuric ions might induce glomerular and tubular injury, aged kidneys, which may not be functioning at full capacity, may be more sensitive to the effects of Hg than normal kidneys. Age-related renal changes and the effects of Hg in the kidney have been characterized separately. However, little is known regarding the influence of nephrotoxicants, such as Hg, on aged kidneys. The purpose of this review was to summarize known findings related to exposure of aged and diseased kidneys to the environmentally relevant nephrotoxicant Hg.

Mechanisms of skin aging induced by EGFR inhibitors

BACKGROUND

The mechanisms of skin aging have not been completely elucidated. Anecdotal data suggests that EGFR inhibition accelerates aging-like skin changes.

OBJECTIVE

The objective of the study was to evaluate the clinical characteristics and investigate the cellular and molecular mechanisms underlying skin changes associated with the use of EFGRIs.

PATIENTS AND METHODS

Patients during prolonged treatment with EGFRIs (>3 months) were analyzed for aging-like skin changes. Baseline EGFR expression was compared in young (<25 years old) vs. old (> 65 years old) skin. In addition, the regulation of extracellular matrix, senescence-associated genes, and cell cycle status was measured in primary human keratinocytes treated with erlotinib in vitro.

RESULTS

There were progressive signs of skin aging, including xerosis cutis, atrophy, rhytide formation, and/or actinic purpura in 12 patients. Keratinocytes treated with erlotinib in vitro showed a significant down-modulation of hyaluronan synthases (HAS2 and HAS3), whereas senescence-associated genes (p21, p53, IL-6, maspin) were upregulated, along with a G1 cell cycle arrest and stronger SA β-Gal activity. There was significantly decreased baseline expression in EGFR density in aged skin, when compared to young controls.

CONCLUSIONS

EGFR inhibition results in molecular alterations in keratinocytes that may contribute to the observed skin aging of patients treated with respective targeted agents.

Plasma Chemokines in Patients with Alcohol Use Disorders: Association of CCL11 (Eotaxin-1) with Psychiatric Comorbidity

Recent studies have linked changes in peripheral chemokine concentrations to the presence of both addictive behaviors and psychiatric disorders. The present study further explore this link by analyzing the potential association of psychiatry comorbidity with alterations in the concentrations of circulating plasma chemokine in patients of both sexes diagnosed with alcohol use disorders (AUD). To this end, 85 abstinent subjects with AUD from an outpatient setting and 55 healthy subjects were evaluated for substance and mental disorders. Plasma samples were obtained to quantify chemokine concentrations [C-C motif (CC), C-X-C motif (CXC), and C-X₃-C motif (CX₃C) chemokines]. Abstinent AUD patients displayed a high prevalence of comorbid mental disorders (72%) and other substance use disorders (45%). Plasma concentrations of chemokines CXCL12/stromal cell-derived factor-1 (p < 0.001) and CX₃CL1/fractalkine (p < 0.05) were lower in AUD patients compared to controls, whereas CCL11/eotaxin-1 concentrations were strongly decreased in female AUD patients (p < 0.001). In the alcohol group, CXCL8 concentrations were increased in patients with liver and pancreas diseases and there was a significant correlation to aspartate transaminase (r = +0.456, p < 0.001) and gamma-glutamyltransferase (r = +0.647, p < 0.001). Focusing on comorbid psychiatric disorders, we distinguish between patients with additional mental disorders (N = 61) and other substance use disorders (N = 38). Only CCL11 concentrations were found to be altered in AUD patients diagnosed with mental disorders (p < 0.01) with a strong main effect of sex. Thus, patients with mood disorders (N = 42) and/or anxiety (N = 16) had lower CCL11 concentrations than non-comorbid patients being more evident in women. The alcohol-induced alterations in circulating chemokines were also explored in preclinical models of alcohol use with male Wistar rats. Rats exposed to repeated ethanol (3 g/kg, gavage) had lower CXCL12 (p < 0.01) concentrations and higher CCL11 concentrations (p < 0.001) relative to vehicle-treated rats. Additionally, the increased CCL11 concentrations in rats exposed to ethanol were enhanced by the prior exposure to restraint stress (p < 0.01). Concordantly, acute ethanol exposure induced changes in CXCL12, CX₃CL1, and CCL11 in the same direction to repeated exposure. These results clearly indicate a contribution of specific chemokines to the phenotype of AUD and a strong effect of sex, revealing a link of CCL11 to alcohol and anxiety/stress.

Is Eotaxin-1 a serum and urinary biomarker for prostate cancer detection and recurrence?

INTRODUCTION AND OBJECTIVES

Eotaxin-1 (CCL11) is a protein expressed in various tissues influencing immunoregulatory processes by acting as selective eosinophil chemo-attractant. In prostate cancer (PCa), the expression and functional role of CCL11 have not been intensively investigated so far. Therefore, the aim of the present study was to investigate the diagnostic or prognostic potential of Eotaxin-1 in PCa patients.

MATERIALS AND METHODS

We analyzed serum from 140 patients who have undergone prostate biopsy due to elevated prostate-specific antigen (PSA) levels as well as serum of 20 individuals with PSA levels < 1ng/ml (healthy control group). Moreover, 40 urine samples were analyzed. A custom-made Q-Plex array ELISA (Quansys Biosciences) for the detection of Eotaxin-1 was performed and Q-View Software used for quantification. In addition, clinical courses of patients documented in our Prostate Biobank database were analyzed. ROC and survival analyses were used to determine the diagnostic and prognostic power of Eotaxin-1 levels.

RESULTS

Serum Eotaxin-1 levels were significantly decreased in PCa (P = 0.006) as well as in benign prostate hyperplasia (P = 0.0006) compared to the control group. ROC analysis revealed that Eotaxin-1 is a significant marker to distinguish PCa from disease-free prostate. Moreover, we found that Eotaxin-1 expression is significantly decreased in Gleason score (GS) 6 (P = 0.0135) and GS 8 (P = 0.0057) patients compared to samples of healthy men, respectively. However, PCa aggressiveness was not predictable by Eotaxin-1 levels. In line with serum analyses, urine Eotaxin-1 was significantly decreased in patients with PCa compared to cancer-free individuals (P = 0.0185) but was not different between cancers of different GS. Patientś follow-up analyses showed no significant correlation between serum Eotaxin-1 levels and time to biochemical recurrence. Survival analyses also revealed no significant changes in progression-free survival among low (≤ 112.2 pg/ml) and high (> 112.2 pg/ml) Eotaxin-1 serum levels.

CONCLUSION

Although this study has not established a prognostic role of Eotaxin-1 in PCa patients, this chemokine may serve as a diagnostic marker to distinguish between disease-free prostate and cancer.

The role of MCP-1-CCR2 ligand-receptor axis in chondrocyte degradation and disease progress in knee osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a common arthritic disease and multifactorial whole-joint disease. Interactions of chemokines and OA is inadequately documented.

RESULTS

In vivo and in vitro studies were conducted to investigate monocyte chemoattractant protein 1 (MCP-1) and receptor chemokine (C-C motif) receptor 2 (CCR2) in chondrocyte degradation and cartilage degeneration. Chondrocytes from 16 OA patients and 6 normal controls were involved in this study. After stimulation of MCP-1, the expression of MCP-1 and CCR2 increased significantly (P < 0.001) and the expression of MMP-13 also increased (P < 0.05). MCP-1 stimulation also induced (or enhanced) the apoptosis of OA chondrocytes (P < 0.05). Additionally, the degradation of cartilage matrix markers (metalloproteinase 3 and 13, MMP3 and MMP13) in the culture medium of normal chondrocytes was also assessed. Furthermore, intra-articular injection of MCP-1 in mouse knees induced cartilage degradation and the CCR2 antagonist did not impede cartilage destroy in rats knees of monosodium iodoacetate (MIA) model.

CONCLUSIONS

The results of this study demonstrate that the MCP-1-CCR2 ligand-receptor axis plays a special role in the initiation and progression of OA pathology. Patients with ambiguous etiology can gain some insight from the MCP-1-CCR2 ligand-receptor axis.

Multiplex cytokine analysis of Werner syndrome

We reported a minor inflammation-driven ageing (inflammageing) assessed by highly sensitive CRP (hsCRP) in normal individuals and patients with Werner syndrome (WS), followed by an ageing associated Th2-biased cytokine change in normal ageing in the previous papers. To further study the association of hsCRP and 26 cytokines/chemokines in 35 WS patients, a multiple cytokine array system was used in the same serum samples as were examined for hsCRP. The serum levels of Th2 cytokines (IL-4, IL-6, IL-10, and GM-CSF), Th1 products (IL-2, TNFα, IL-12, and IFNγ) and monocyte/macrophage products (MCP-1, basic FGF and G-CSF) in WS were significantly elevated compared with normal ageing. Elevated hsCRP level in WS was significantly correlated with IL-6, IL-12 and VEGF levels, if age and sex were taken into account. A pro-inflammatory cytokine/chemokine circuit-stimulated immunological shift to Th2 in WS was similar to normal ageing. These cytokine/chemokine changes may induce a systemic chronic inflammation monitored by hsCRP, though these immunological changes in WS were more complicated than normal ageing, possibly due to the WS-specific chronic inflammation such as skin ulcer, diabetes mellitus and central obesity with visceral fat deposition. Further study may warrant the pathophysiology of Th2 shift and Th2-biased inflammageing in normal ageing and WS.

Cytokines profile in hypertensive patients with left ventricular remodeling and dysfunction

There is strong evidence that inflammatory mediators play a key role in the progression to heart failure in patients with systemic hypertension (HTN). The present study aimed to identify a set of cytokines that are associated with early left ventricular (LV) remodeling and dysfunction as captured by echocardiography in patients with HTN in a cross-sectional case-control study nested within the FLEMish study on ENvironment, Genes and Health Outcome. We identified three groups of participants from the cohort: normotensive subjects (normotension; n = 30), HTN with normal LV structure and function (HTN [LV-]; n = 30), and HTN with evidence of adverse LV remodeling (HTN [LV+]; n = 50). We measured cytokines using a 63-plex Luminex platform. Using partial least squares-discriminant analysis, we constructed three latent variables from the measured cytokines that explained 35%-45% of the variance between groups. We identified five common cytokines (interleukin 18, monokine induced by gamma interferon, hepatocyte growth factor, epithelial neutrophil-activating peptide 78, and vascular endothelial growth factor D) with a stable signal which had a major impact on the construction of the latent variables. Among these cytokines, after adjustment for confounders, interleukin 18 remained significantly different between HTN participants with and without LV involvement (P = .02). Moreover, granulocyte-macrophage colony-stimulating factor and leptin showed a consistent upward trend in all HTN patients compared with normotensive subjects. In conclusion, in HTN patients with LV remodeling or/and dysfunction, we identified a set of cytokines strongly associated with LV maladaptation. We also found a distinct profile of inflammatory biomarkers that characterize HTN.

Circulating Cytokine Levels as Markers of Inflammation in Philadelphia Negative Myeloproliferative Neoplasms: Diagnostic and Prognostic Interest

Cytokines are well known mediators of numerous physiological and pathological processes. They contribute to the regulation of normal hematopoiesis but increasing data suggest that they also have a clinical impact in some hematopoietic malignancies. In particular, there is evidence that cytokines are implicated in the functional symptoms of Philadelphia negative myeloproliferative neoplasms (Ph- MPNs), suggesting that evaluation of circulating levels of cytokines could be of clinical interest for the characterization of patients at the time of diagnosis and for disease prognosis. In this review, we present the current knowledge on alteration of circulating cytokine profiles in MPNs and their role in myelofibrosis pathogenesis. Phenotypic correlation, prognostic value of cytokines, and impact of JAK inhibitors are also discussed.

Systematic Review of the Neurobiological Relevance of Chemokines to Psychiatric Disorders

Psychiatric disorders are highly prevalent and disabling conditions of increasing public health relevance. Much recent research has focused on the role of cytokines in the pathophysiology of psychiatric disorders; however, the related family of immune proteins designated chemokines has been relatively neglected. Chemokines were originally identified as having chemotactic function on immune cells; however, recent evidence has begun to elucidate novel, brain-specific functions of these proteins of relevance to the mechanisms of psychiatric disorders. A systematic review of both human and animal literature in the PubMed and Google Scholar databases was undertaken. After application of all inclusion and exclusion criteria, 157 references were remained for the review. Some early mechanistic evidence does associate select chemokines with the neurobiological processes, including neurogenesis, modulation of the neuroinflammatory response, regulation of the hypothalamus–pituitary–adrenal axis, and modulation of neurotransmitter systems. This early evidence however does not clearly demonstrate any specificity for a certain psychiatric disorder, but is primarily relevant to mechanisms which are shared across disorders. Notable exceptions include CCL11 that has recently been shown to impair hippocampal function in aging – of distinct relevance to Alzheimer’s disease and depression in the elderly, and pre-natal exposure to CXCL8 that may disrupt early neurodevelopmental periods predisposing to schizophrenia. Pro-inflammatory chemokines, such as CCL2, CCL7, CCL8, CCL12, and CCL13, have been shown to drive chemotaxis of pro-inflammatory cells to the inflamed or injured CNS. Likewise, CX3CL has been implicated in promoting glial cells activation, pro-inflammatory cytokines secretion, expression of ICAM-1, and recruitment of CD4+ T-cells into the CNS during neuroinflammatory processes. With further translational research, chemokines may present novel diagnostic and/or therapeutic targets in psychiatric disorders.

The effects of age and gender on plasma levels of 63 cytokines

Cytokines play important roles as regulators of cell functions, and over the last decades a number of cytokine assays have been developed. The aim of the present study was to investigate the effects of age and gender on a large number of cytokines. Plasma samples were collected from 33 healthy blood donors. The samples were analyzed using a multiplex proximity extension assay (PEA) allowing simultaneous measurement of 92 cytokines and four technical controls. Biomarkers with less than 80% quantitative results were excluded leaving 63 cytokines that were analyzed for the effects of gender and age. The plasma level of three of the investigated biomarkers (DNER, MCP-4 and MMP-10) were found to be significantly different for the two genders (adjusted p-value<0.05), and 15 of the biomarkers (CCL11, CCL25, CDCP1, CSF-1, CXCL11, CXCL9, FGF-23, Flt3L, HGF, IL-10RB, MCP-3, MCP-4, MMP-10, OPG, VEGF-A) were significantly associated with age. This study reveals the effects of age and gender on a large number of cytokine assays. CXCL5 and TNFB were significantly higher in females, while the other markers with significant gender-dependent differences were higher in males. For the markers that were significantly associated with age, only CXCL6 was found to decrease with age, while the other biomarkers increased with age.

DDX60 Is Involved in RIG-I-Dependent and Independent Antiviral Responses, and Its Function Is Attenuated by Virus-Induced EGFR Activation

RIG-I-mediated type I interferon (IFN) production and nuclease-mediated viral RNA degradation are essential for antiviral innate immune responses. DDX60 is an IFN-inducible cytoplasmic helicase. Here, we report that DDX60 is a sentinel for both RIG-I activation and viral RNA degradation. We show that DDX60 is an upstream factor of RIG-I that activates RIG-I signaling in a ligand-specific manner. DDX60 knockout attenuates RIG-I signaling and significantly reduces virus-induced type I IFN production in vivo. In addition, we show that DDX60 is involved in RIG-I-independent viral RNA degradation. DDX60 and RIG-I adaptor MAVS double-knockout mice reveal a role for DDX60-dependent RNA degradation in antiviral responses. Several viruses induced DDX60 phosphorylation via epidermal growth factor receptor (EGFR), leading to attenuation of the DDX60 antiviral activities. Our results define DDX60 as a sentinel for cytoplasmic antiviral response, which is counteracted by virus-mediated EGF receptor activation.

CCL2, CXCL8, CXCL9 and CXCL10 serum levels increase with age but are not altered by treatment with hydroxychloroquine in patients with osteoarthritis of the knees

AIM

Osteoarthritis (OA) is a major cause of morbidity and incapacity in the elderly. This study evaluates serum levels of the chemokines CCL2, CXCL8, CXCL9, and CXCL10 in 16 patients with primary OA of the knees, and investigates how treatment with hydroxychloroquine (HCQ) for 4 months affects these chemokine levels.

METHOD

Thirteen elderly patients received a placebo. Healthy control groups consisted of 10 elderly individuals (age > 60 years) with no clinical or radiological evidence of OA (CT-O), and 10 young adult individuals, (CT-Y group, age < 40 years).

RESULTS

The CT-Y group presented lower levels of all chemokines studied, in comparison to the other groups. HCQ treatment did not alter the serum levels of CCL2 (P = 0.80), CXCL8 (P = 0.76), CXCL9 (P = 0.95) and CXCL10 (P = 0.74) in OA patients.

CONCLUSION

Hydroxychloroquine treatment did not alter the serum levels of CCL2, CXCL8, CXCL9 or CXCL10 in patients with OA of the knees, although increased serum levels correlated with aging for all subjects, including controls.

Mechanisms of maladaptive repair after AKI leading to accelerated kidney ageing and CKD

Acute kidney injury is an increasingly common complication of hospital admission and is associated with high levels of morbidity and mortality. A hypotensive, septic, or toxic insult can initiate a cascade of events, resulting in impaired microcirculation, activation of inflammatory pathways and tubular cell injury or death. These processes ultimately result in acutely impaired kidney function and initiation of a repair response. This Review explores the various mechanisms responsible for the initiation and propagation of acute kidney injury, the prototypic mechanisms by which a substantially damaged kidney can regenerate its normal architecture, and how the adaptive processes of repair can become maladaptive. These mechanisms, which include G2/M cell-cycle arrest, cell senescence, profibrogenic cytokine production, and activation of pericytes and interstitial myofibroblasts, contribute to the development of progressive fibrotic kidney disease. The end result is a state that mimics accelerated kidney ageing. These mechanisms present important opportunities for the design of targeted therapeutic strategies to promote adaptive renal recovery and minimize progressive fibrosis and chronic kidney disease after acute insults.

The aging kidney: increased susceptibility to nephrotoxicity

Three decades have passed since a series of studies indicated that the aging kidney was characterized by increased susceptibility to nephrotoxic injury. Data from these experimental models is strengthened by clinical data demonstrating that the aging population has an increased incidence and severity of acute kidney injury (AKI). Since then a number of studies have focused on age-dependent alterations in pathways that predispose the kidney to acute insult. This review will focus on the mechanisms that are altered by aging in the kidney that may increase susceptibility to injury, including hemodynamics, oxidative stress, apoptosis, autophagy, inflammation and decreased repair.

Distinct age-matched serum biomarker profiles in patients with cutaneous T-cell lymphoma

Immunological functions decline with age. Because MS/SzS predominately affects the elderly, it is important to distinguish age-related from cancer-specific changes. Also, MF and SzS are malignancies of CD4(+) T-lymphocytes, further compromising an immune state of the patients. The objectives of this study were to distinguish disease-specific immunological deterioration by performing comparative age-matched Luminex multiplex assessment of 34 serum biomarkers between patients with MF/SzS, HIV-infected individuals and normal controls. Controlling for age, expression level appears to significantly differ between patients with MF/SzS and controls for the following biomarkers: G-CSF, IL-5, MIP-1β, TNF-α, VEGF, EOTAXIN, IL-8, IL-12, IL-2R, IP10, MCP-1, MIG, TNFR1 and TNFR2 (P < 0.05), while others showed normal age-related changes. Interestingly, cluster analysis placed MF/SzS profiles closer to HIV. This further underscores an immunologically compromised state of patients with MF/SzS and suggests its potential self-perpetuating role in disease progression.

Rapid transport of CCL11 across the blood-brain barrier: regional variation and importance of blood cells

Increased blood levels of the eotaxin chemokine C-C motif ligand 11 (CCL11) in aging were recently shown to negatively regulate adult hippocampal neurogenesis. How circulating CCL11 could affect the central nervous system (CNS) is not clear, but one possibility is that it can cross the blood-brain barrier (BBB). Here, we show that CCL11 undergoes bidirectional transport across the BBB. Transport of CCL11 from blood into whole brain (influx) showed biphasic kinetics, with a slow phase preceding a rapid phase of uptake. We found that the slow phase was explained by binding of CCL11 to cellular components in blood, whereas the rapid uptake phase was mediated by direct interactions with the BBB. CCL11, even at high doses, did not cause BBB disruption. All brain regions except striatum showed a delayed rapid-uptake phase. Striatum had only an early rapid-uptake phase, which was the fastest of any brain region. We also observed a slow but saturable transport system for CCL11 from brain to blood. C-C motif ligand 3 (CCR3), an important receptor for CCL11, did not facilitate CCL11 transport across the BBB, although high concentrations of a CCR3 inhibitor increased brain uptake without causing BBB disruption. Our results indicate that CCL11 in the circulation can access many regions of the brain outside of the neurogenic niche via transport across the BBB. This suggests that blood-borne CCL11 may have important physiologic functions in the CNS and implicates the BBB as an important regulator of physiologic versus pathologic effects of this chemokine.

Cytokines as biomarkers in rheumatoid arthritis

RA is a complex disease that develops as a series of events often referred to as disease continuum. RA would benefit from novel biomarker development for diagnosis where new biomarkers are still needed (even if progresses have been made with the inclusion of ACPA into the ACR/EULAR 2010 diagnostic criteria) and for prognostic notably in at risk of evolution patients with autoantibody-positive arthralgia. Risk biomarkers for rapid evolution or cardiovascular complications are also highly desirable. Monitoring biomarkers would be useful in predicting relapse. Finally, predictive biomarkers for therapy outcome would allow tailoring therapy to the individual. Increasing numbers of cytokines have been involved in RA pathology. Many have the potential as biomarkers in RA especially as their clinical utility is already established in other diseases and could be easily transferable to rheumatology. We will review the current knowledge's relation to cytokine used as biomarker in RA. However, given the complexity and heterogeneous nature of RA, it is unlikely that a single cytokine may provide sufficient discrimination; therefore multiple biomarker signatures may represent more realistic approach for the future of personalised medicine in RA.

The aging kidney revisited: a systematic review

As for the whole human body, the kidney undergoes age-related changes which translate in an inexorable and progressive decline in renal function. Renal aging is a multifactorial process where gender, race and genetic background and several key-mediators such as chronic inflammation, oxidative stress, the renin-angiotensin-aldosterone (RAAS) system, impairment in kidney repair capacities and background cardiovascular disease play a significant role. Features of the aging kidney include macroscopic and microscopic changes and important functional adaptations, none of which is pathognomonic of aging. The assessment of renal function in the framework of aging is problematic and the question whether renal aging should be considered as a physiological or pathological process remains a much debated issue. Although promising dietary and pharmacological approaches have been tested to retard aging processes or renal function decline in the elderly, proper lifestyle modifications, as those applicable to the general population, currently represent the most plausible approach to maintain kidney health.

Blood expression levels of chemokine receptor CCR3 and chemokine CCL11 in age-related macular degeneration: a case-control study

BACKGROUND

Dysregulation of the CCR3/CCL11 pathway has been implicated in the pathogenesis of choroidal neovascularisation, a common feature of late age-related macular degeneration (AMD). The aim of this study was to investigate the expression of CCR3 and its ligand CCL11 in peripheral blood in patients with neovascular AMD.

METHODS

Patients with neovascular AMD and healthy controls were included. Blood samples were obtained and prepared for flow cytometry to investigate the expression of CCR3. Levels of CCL11 were measured in plasma using Cytometric Bead Array. Differences between the groups were tested using Kruskal-Wallis test and Mann-Whitney U test.

RESULTS

Patients (n = 83) with neovascular AMD and healthy control persons (n = 114) were included in the study. No significant difference in the expression of CCR3 was found on CD9+ granulocytes when comparing patients suffering from neovascular AMD with any of the control groups. We did not find any alteration in CCL11 levels in patients among the age matched groups. There was no correlation between expression of CCR3/CCL11 and clinical response to treatment with anti-vascular endothelial growth factor (VEGF).

CONCLUSION

Our results do not suggest a systemic alteration of the CCR3/CCL11 receptor/ligand complex in patients with neovascular AMD.

Multiplexed measurements of immunomodulator levels in peripheral blood of healthy subjects: Effects of analytical variables based on anticoagulants, age, and gender

Multiplex microbead immunoassay (MMIA) is a powerful technology for a wide range of biomedical and clinical applications. It is important to study the normal concentration ranges of immunomodulators under different sample preparation conditions and age groups of subjects in order to more precisely determine their reference values for use in assessing alterations of their levels in disease. The aim of this study was to determine the plasma concentrations of immunomodulators (cytokines, chemokines, and growth factors) in the peripheral blood from healthy subjects by the use of a large multiplex panel, and to determine the effects of different anticoagulants, age, and gender on the immunomodulator levels. In addition, the assay precision for these biomarker analytes was determined. Plasma samples from 107 healthy subjects, aged 18 to 85 years, were collected in three different anticoagulants (sodium citrate, EDTA, Heparin); corresponding serum samples were also obtained. Multiplex microbead immunoassays were performed for measuring a total of 23 analytes including chemokines, cytokines, and growth factors (IL-1β, IL-1ra, IL-2, IL-6, IL-7, IL-8, IL-12 p70, IL-17, IFN-γ, IP-10, MCP-1, PDGF-BB, RANTES, TNF-α, IL-1a, IL-16, HGF, MIG, TNF-β, PDGF-ABBB, EGF, Flt-3 Ligand, VEGF). For these analytes, our results showed that the anticoagulant affected the concentration measurements and the coefficients of variation. However, the relative levels of the analytes (profiles) of samples collected in a particular anticoagulant are consistent. The analytes IL-1β, IL-7, Flt-3 Ligand, and IL-12p70 show the largest variation (up to fourfold) between the age groups. In addition, no statistically significant differences in the level of the analytes were found between the sexes.

Life-long endurance exercise in humans: circulating levels of inflammatory markers and leg muscle size

Human aging is associated with a loss of skeletal muscle and an increase in circulating inflammatory markers. It is unknown whether endurance training (Tr) can prevent these changes. Therefore we studied 15 old trained (O-Tr) healthy males and, for comparison, 12 old untrained (O-Un), 10 Young-Tr (Y-Tr) and 12 Young-Un (Y-Un). Quadriceps size, VO2 peak, CRP, IL-6, TNF-α and its receptors, suPAR, lipid profile, leucocytes and glucose homeostasis were measured. Tr was associated with an improved insulin profile (p<0.05), and lower leucocyte (p<0.05) and triglyceride levels (p<0.05), independent of age. Aging was associated with poorer glucose control (p<0.05), independent of training. The age-related changes in waist circumference, VO2 peak, cholesterol, LDL, leg muscle size, CRP and IL-6 were counteracted by physical activity (p<0.05). A significant increase in suPAR with age was observed (p<0.05). Most importantly, life-long endurance exercise was associated with a lower level of the inflammatory markers CRP and IL-6 (p<0.05), and with a greater thigh muscle area (p<0.05), compared to age-matched untrained counterparts. These findings in a limited group of individuals suggest that regular physical endurance activity may play a role in reducing some markers of systemic inflammation, even within the normal range, and in maintaining muscle mass with aging.