Self-rated health in individuals with and without disease is associated with multiple biomarkers representing multiple biological domains.

Self-rated health (SRH) is one of the most frequently used indicators in health and social research. Its robust association with mortality in very different populations implies that it is a comprehensive measure of health status and may even reflect the condition of the human organism beyond clinical diagnoses. Yet the biological basis of SRH is poorly understood. We used data from three independent European population samples (N approx. 15,000) to investigate the associations of SRH with 150 biomolecules in blood or urine (biomarkers). Altogether 57 biomarkers representing different organ systems were associated with SRH. In almost half of the cases the association was independent of disease and physical functioning. Biomarkers weakened but did not remove the association between SRH and mortality. We propose three potential pathways through which biomarkers may be incorporated into an individual's subjective health assessment, including (1) their role in clinical diseases; (2) their association with health-related lifestyles; and (3) their potential to stimulate physical sensations through interoceptive mechanisms. Our findings indicate that SRH has a solid biological basis and it is a valid but non-specific indicator of the biological condition of the human organism.

Novel ageing-biomarker discovery using data-intensive technologies.

Ageing is accompanied by many visible characteristics. Other biological and physiological markers are also well-described e.g. loss of circulating sex hormones and increased inflammatory cytokines. Biomarkers for healthy ageing studies are presently predicated on existing knowledge of ageing traits. The increasing availability of data-intensive methods enables deep-analysis of biological samples for novel biomarkers. We have adopted two discrete approaches in MARK-AGE Work Package 7 for biomarker discovery; (1) microarray analyses and/or proteomics in cell systems e.g. endothelial progenitor cells or T cell ageing including a stress model; and (2) investigation of cellular material and plasma directly from tightly-defined proband subsets of different ages using proteomic, transcriptomic and miR array. The first approach provided longitudinal insight into endothelial progenitor and T cell ageing. This review describes the strategy and use of hypothesis-free, data-intensive approaches to explore cellular proteins, miR, mRNA and plasma proteins as healthy ageing biomarkers, using ageing models and directly within samples from adults of different ages. It considers the challenges associated with integrating multiple models and pilot studies as rational biomarkers for a large cohort study. From this approach, a number of high-throughput methods were developed to evaluate novel, putative biomarkers of ageing in the MARK-AGE cohort.

Relationship between cardiac tissue glycation and skin autofluorescence in patients with coronary artery disease.

AIM: During ageing, advanced glycation end-products (AGEs) accumulate in extracellular matrix proteins like collagen and contribute to a decline in organ function. As skin autofluorescence (sAF) can assess subcutaneous accumulation of fluorescent AGEs, this study aimed to investigate the relationship between AGE-modified cardiac tissue collagen and AGE-related sAF in coronary artery bypass graft (CABG) surgery patients. METHODS: Between January 2011 and January 2012, data from 72 consecutive male patients undergoing isolated CABG were prospectively recorded. Collagen fractions were isolated from the right atrial appendages of these patients by proteolysis and collagenase digestion. Collagen was quantified by hydroxyproline assay, and AGEs by AGE-related intrinsic fluorescence; sAF was measured using an autofluorescence reader. RESULTS: Biochemical analysis showed that the insoluble cardiac collagen fraction contained the highest amounts of accumulated AGEs; the AGE-related intrinsic fluorescence of this fraction increased with age (P=0.0001), blood glucose (P=0.002), HbA1c (P=0.01) and sAF (P=0.008). CONCLUSION: This study demonstrated for the first time a relationship between cardiac tissue glycation and AGE-related sAF. In addition, cardiac tissue glycation was associated with age, blood glucose and long-term glucose values in patients with coronary artery disease.

Influence of central nervous system-acting drugs on results of cognitive testing in geriatric inpatients.

INTRODUCTION: Growing evidence shows a high correlation between extensive use of central nervous system-acting drugs (CNSADs) in elderly patients and adverse drug reactions (ADRs) such as falls, fractures, and mortality. RESEARCH QUESTION: Are results of cognitive testing with the Mini Mental Status Examination (MMSE) influenced by use of CNSADs? SETTING: Geriatric inpatient service for acute, subacute, and rehabilitation care. METHODS: Secondary combined analysis of two prospective, single-center study cohorts (PROPSYC, 2011 and AGE OUT, 2012) with identical procedure for the MMSE at a tertiary hospital. RESULTS: Overall, 395 patients were included, 144 male (M) and 251 female (F). Mean age was 80.0 ± 8.4 years (M 76.7 ± 9.1, F 81.9 ± 7.3, p = 0.0000). Mean MMSE points were 22.9 ± 4.8 (M 23.2 ± 4.6, F 22.6 ± 5.0, p = 0.211). In total, 258 patients (65.3 %) used drugs with potential adverse cognitive properties. Analgesics with central activity were given to 117 of 395 patients (29.6 %). Low-potency opioids (tramadol hydrochloride, tilidine) were identified in 60 patients and high-potency opioids in 57 patients. Antidepressants were used in 66 patients, benzodiazepines in 26, and hypnotics in 11, while 38 patients received other CNSADs. We only found significant correlations with the results of cognitive testing for sedatives (diazepam and oxazepam, Pearson's r - 0.79, p = 0.05), but not for lorazepam. CONCLUSION: Our analysis shows an influence of sedatives (diazepam and oxazepam, but not lorazepam) on cognitive testing with the MMSE in users of CNSADs.

Intraoperative sRAGE kinetics. A new age-related outcome predictor of cardiac surgery.

BACKGROUND: Glycated proteins (advanced glycation endproducts, AGE) in tissue are associated with degenerative diseases. This study evaluated the role of sRAGE (soluble receptor for advanced glycation endproducts), a decoy receptor of AGEs in blood, for the outcome of patients after coronary artery bypass grafting (CABG). METHODS: A total of 90 patients undergoing CABG were analysed in two centres. Perioperative blood samples were collected before surgery up to 1 week postoperatively. sRAGE was measured by ELISA. Patients were subdivided regarding age (< 64 versus > 70 years, 14 % versus 35 % female), euroSCORE (< 3 versus > 4, 14 % versus 29 % female) and sRAGE changes between sternotomy and end of the operation (< 30 % versus > 45 %, 33 % versus 33 % female) and subsequently analysed with respect of postoperative outcome parameters. RESULTS: Preoperative sRAGE values did not correlate with the outcome of the patients. sRAGE levels increase within 10 min from 1,539 ± 96 to 5,311 ± 187 pg/ml after sternotomy, then returning to baseline levels within 2 days after surgery. Comparing the analysed possible risk factors age, euroSCORE and sRAGE changes, no difference was observed regarding 30-day mortality. Age and the euroSCORE are superior with respect of tachyarrythmia, whereas sRAGE kinetics seems to be superior with respect of prolonged postoperative respiration time/stay in the intensive care unit or catecholamine support. CONCLUSION: A prolonged, increased intraoperative sRAGE level is a new outcome predictor for patients undergoing CABG surgery, mutually complementary to the euroSCORE.

Immediate effects of individualized heparin and protamine management on hemostatic activation and platelet function in adult patients undergoing cardiac surgery with tranexamic acid antifibrinolytic therapy.

OBJECTIVE: This randomized prospective study was initiated to clarify whether individualized heparin and protamine dosing has immediate effects on hemostatic activation and platelet function in adult cardiac surgery. METHODS: Sixty adults undergoing elective coronary artery bypass grafting (CABG) were assigned to receive individualized heparin and protamine (HMS group, n= 29) or a standard dose (ACT group, n=24). Measures of thrombin generation and Multiplate (Verum Diagnostica, Munich, Germany) platelet function tests were performed before and after cardiopulmonary bypass (CPB). RESULTS: HMS patients received higher heparin (p = 0.006) and lower protamine (p<0.001) doses. Post-CPB, HMS managed patients showed significantly lower thrombin generation (thrombin-antithrombin (TAT) p<0.02) than the ACT group. Moreover, HMS managed patients had a better preservation of platelet function (COL p = 0.013; ADP p = 0.04; TRAP p = 0.04). CONCLUSION: An individualized and stable heparin concentration and appropriate dosing of protamine can reduce thrombin generation and preserve platelet function, even in short-time CPB.

Glutamine and alanine-induced differential expression of intracellular IL-6, IL-8, and TNF-α in LPS-stimulated monocytes in human whole-blood.

To investigate the effects of the commonly-used immunomodulators l-glutamine, l-alanine, and the combination of both l-alanyl-l-glutamine (Dipeptamin(®)) on intracellular expression of IL-6, IL-8, and TNF-α during endotoxemia, lipopolysaccharide (LPS)-stimulated human monocytes in a whole blood system were investigated by flow cytometry. Whole blood of twenty-seven healthy volunteers was stimulated with LPS and incubated with three different amino acid solutions (1. l-glutamine, 2. l-alanine, 3. l-alanyl-l-glutamine, each concentration 2 mM, 5 mM, incubation time 3 h). CD14(+) monocytes were phenotyped in whole-blood and intracellular expression of cytokines was assessed by flow cytometry. Our investigations showed for the first time in whole blood probes, imitating best physiologically present cellular interactions, that l-glutamine caused a dose-independent inhibitory effect on IL-6 and TNF-α production in human monocytes stimulated with LPS. However, l-alanine had contrary effects on IL-6 expression, significantly upregulating expression of IL-6 in LPS-treated monocytes. The impact of l-alanine on the expression of TNF-α was comparable with glutamine. Neither amino acid was able to affect IL-8 production in LPS-stimulated monocytes. The combination of both did not influence significantly IL-6 and IL-8 expression in monocytes during endotoxemia, however strongly reduced TNF-α production. For the regulation of TNF-α, l-glutamine, l-alanine and the combination of both show a congruent and exponentiated downregulating effect during endotoxemia, for the modulation of IL-6, l-glutamine and l-alanine featured opposite regulation leading to a canceling impact of each other when recombining both amino acids.

The effect of an AGE-rich dietary extract on the activation of NF-κB depends on the cell model used.

Advanced glycation end products (AGEs) are the results of a chemical reaction of reactive aldehydes, such as sugars, with amino acid side chains. AGEs can be formed by the heating process of the food and taken up with the diet. They are thought to be at least in part responsible for major complications in age-related diseases. The activation of the transcription factor NF-κB plays a prominent role in AGE-induced cell signaling. This study aimed to elucidate the effect of exogenous AGEs on NF-κB activation in different cell models. Therefore a bread crust extract commonly found in a Western diet was chosen as an AGE-rich sample. Using RP-HPLC, 23 fractions from the bread crust extract were obtained. The immunodetection with specific antibodies for N-carboxymethyllysine arg-pyrimidine, pentosidine and 3-deoxyglucosone-imidazolone showed that the majority of the AGEs were located in the late fractions. Three different NF-κB reporter cell lines including NF-κB/293/GFP-Luc™, NF-κB/Jurkat/GFP™ and RAW/NF-κB/SEAPorter™ were stimulated with the 23 fractions. There was no direct correlation between the AGE content in the fractions and the cell activation. Whereas in Jurkat-T-cells, the stimulation seems to correlate at least in part with the AGE content, in HEK-293 epithelial cell nearly all fractions can stimulate NF-κB. In macrophages few fractions stimulate NF-κB whereas some fractions even inhibit the p38 MAP kinase. The highest expression of the AGE receptors like RAGE, AGER-1, AGER-2 and AGER-3 was detected in the macrophage RAW cell line. In conclusion the present study showed a new approach to study bioactive compounds in bread crust extract. The identification of the bioactive compounds is still ongoing.

[Protein glycation as a pathological mechanism in diabetes]. / Proteinglykierung als pathophysiologischer Mechanismus bei Diabetes.

The incidence of diabetes has increased in the recent years. Diabetes is characterized by increased sugar concentrations in the blood. Due to this dysregulation, more carbohydrate-induced modification of proteins - so-called advanced glycation end products (AGEs) - are formed endogenously by non-enzymatic reactions. These are discussed to be at least in part responsible for diabetes-associated diseases. The accumulation of AGEs in the tissue can be used as a biomarker for patient outcome. In contrast, the effects of the uptake of AGEs from nutrition are still unclear.

RAGE influences obesity in mice. Effects of the presence of RAGE on weight gain, AGE accumulation, and insulin levels in mice on a high fat diet.

BACKGROUND: The metabolic syndrome is defined by the presence of obesity, insulin resistance, dyslipidemia, and hypertension. Advanced glycation end products (AGEs) are stable end products of the Maillard reaction, whereby AGE accumulation is considered not only a biomarker of aging but is also associated with several degenerative diseases. AGEs are recognized by several receptor molecules of which the receptor of AGEs (RAGE) is currently the most intensively studied receptor. Activation of RAGE causes an unfavorable proinflammatory state and deletion of RAGE in diabetic animals has been reported to protect against atherosclerosis. AGEs and a high fat diet are associated with cardiovascular diseases, whereas is still not clear whether a direct link between high fat nutrition and AGEs exists in vivo. MATERIALS AND METHODS: C57BL/6 and C57BL/6 RAGE -/- mice were fed a high fat diet to induce obesity. Weight, insulin, lipid levels, AGE modifications, and cardiac gene expression were analyzed. RESULTS: The absence of RAGE resulted in accelerated weight gain, increased plasma cholesterol, and higher insulin levels in obese mice. The hearts of normal and obese RAGE -/- mice contained lower levels of the AGE arginine-pyrimidine and 3DG-imidazolone than RAGE + / + animals. RAGE -/- mice also exhibited lower expression of the genes encoding the antioxidative enzymes MnSOD, Cu/ZnSOD, and ceruloplasmin in cardiac tissue, whereas the AGE receptors AGER-1, -2, and -3 were equally expressed in both genotypes. Obese mice of both strains expressed increased amounts of AGER-2. Only obese RAGE + / + mice exhibited a reduced mRNA accumulation of Cu/Zn SOD. CONCLUSION: These data suggest that RAGE is involved in the development of obesity and insulin resistance.

[Geriatrics: an introduction from a gerontological point of view]. / Geriatrie: eine Einführung aus gerontologischer Sicht.

Geriatrics is in comparison to the other medical professions a relatively new discipline. The calendarical age is not suitable for the characterization of its patient population, the multimorbid old patients. The biofunctional age in terms of the ICF is a better choice. It is characterized in part by physical, psychical, and social context-factors, which can be analysed by geriatric assessments. A better cooperation between basic science orientated gerontological disciplines with the geriatrics will be, beside the implementation into the university medicine and the standardized uniform professional training, of essential importance for the further development of geriatric medicine.

[Vessel aging. The role of oxidative stress and protein glycation]. / Gefäßalterung. Die Rolle von oxidativem Stress und Proteinglykierung.

The slow procession of the primary mechanisms of aging leads, at first, to unnoticed changes in the vascular system. Endothelial dysfunction is one of the earliest markers in aging vessels, caused by oxidative stress via the reduction of the availability of NO, on the one hand, and the nitrosylation of proteins, on the other hand. At the same time, glycation of the proteins of the extracellular matrix leads to stiffening of the vessel wall. Together with the loss of elastic fibers, e.g., elastin, this leads to the age-related changes of the vessels. Knowledge of these primary mechanisms of aging may lead to the development of new drugs.

[Biofunctional age diagnosis in humans. Potentials and limits]. / Biofunktionale Alter(n)sdiagnostik des Menschen. Potenziale und Grenzen.

The demand and requirements for valid, practicable, and reliable procedures for age diagnosis are increasing worldwide. In contrast, few studies and only a small number of procedures exist. The authors review the theoretical and methodological requirements for the development of models for age diagnostics. They describe the fundamentals for further studies, based on an analysis of current gerontological research in this area. A following publication will report the valid systems measuring vitality and biofunctional age(ing) of human beings.

HbA1c during pregnancy: its relationship to meal related glycaemia and neonatal birth weight in patients with diabetes.

OBJECTIVE: Although home blood glucose (HBG) profiles correlate closely with HbA1c, the strength of the relationship during pregnancy is unclear due to physiological changes which can induce subnormal HbA1c levels. We therefore aimed to establish the strength of the association between mean HBG profiles and HbA1c in diabetic pregnancies and whether HbA1c levels and glycaemic variability affects neonatal birth weight (NBW). STUDY DESIGN: 7-point glycaemic profiles performed throughout pregnancy were obtained retrospectively in 94 consecutive patients attending the diabetes antenatal clinic and compared to the corresponding mean HbA1c levels. RESULTS: There was a significant linear correlation between mean HBG and HbA1c (HbA1c=0.5HBG+3.1, r=0.71, p<0.0001). Multiple regression analysis demonstrated that both pre- and post-prandial HBG levels correlated significantly and independently with HbA1c, correlation coefficients (r) were 0.63 and 0.65, respectively both p<0.0001. Significant correlations were also observed in patients with gestational diabetes (n=67, mean HbA1c=6.11, r=0.67; p<0.0001) and type 1 diabetes (n=18, mean HbA1c=6.75, r=0.64; p=0.004). All meal related HBG measurements showed similar significant correlations with HbA1c (r values pre- and post-breakfast, pre- and post-lunch, pre- and post-tea and pre-bed are 0.56, 0.55, 0.59, 0.55, 0.56, 0.59, 0.51, respectively p<0.0001 for all time points). Post hoc analysis showed that NBW increased with higher levels of HbA1c; NBW (centiles)+/-S.D. for HbA1c <6.5% versus >6.5% was 78.9%+/-29.2 versus 90.2%+/-18.6, p=0.02. CONCLUSION: Mean HbA1c levels are closely correlated to all meal related glucose measurements during pregnancy. It is therefore a reliable indicator of overall glycaemic control among patients with diabetes during pregnancy.

Inflammatory response in on- versus off-pump myocardial revascularization: is ECC really the culprit?

A review of inflammatory mediators in on- versus off-pump surgery reveals that parameters of systemic inflammation differ quantitatively, not qualitatively between these approaches. Mediator system and cellular activation is observed after surgical trauma and following ischemia/reperfusion. Such activation is also modulated by genetic factors. The available literature does not permit definitive conclusions to be made on the advantages of off-pump surgery with respect to the systemic inflammatory response. The relationship between mediator systems and clinical course needs to be assessed in large patient populations to demonstrate to what extent off-pump surgery is more than just theoretically superior to on-pump surgery.

Dicarbonyl-mediated protein modifications affect matrix metalloproteinase (MMP) activity.

Advanced age is linked with an increased incidence of epithelial tumours (carcinomas) including lung tumours. However, a slowing rate of the increase of age-specific cancer incidence is demonstrated at very advanced ages, and elderly patients also develop less invasive and metastatic tumours than their younger counterparts. Matrix metalloproteinases (MMPs) are commonly upregulated in the stromal compartment of the carcinoma tissue and are believed to promote invasion and metastasis. As the increased serum and tissue level of advanced glycation end products (AGEs) is a characteristic feature of old humans, our study focused on the impact of AGEs on the activity of MMPs released from lung fibroblasts (WI- 38). The collagen gel zymography technique showed the primary presence of MMP-2 in the conditioned medium of the WI-38 fibroblasts, which was even higher in senescent WI-38 fibroblasts. Subsequent treatment of the WI- 38 conditioned medium with the dicarbonyl compound glyoxal, a highly reactive precursor of the AGE formation, resulted in a dose-dependent reduction of the MMP-2 activity. Therefore, our study suggests that the age-associated increase in AGEs might be one potential host factor responsible for the less invasiveness of tumours at very advanced age.

Advanced glycation end products, diabetes and ageing.

Advanced glycation end products (AGEs) are formed in vivo by a non-enzymatic reaction of proteins with carbohydrates and accumulate in many tissues during ageing. They are discussed as being responsible for many age- and diabetes-related diseases. On the other hand, AGEs are formed by the heating of food and are taken up by the nutrition. The contribution of endogenously formed versus exogenous intake of AGEs to age-related diseases is still under discussion.