Central and Peripheral Circulation Differ during Off-Pump Coronary Artery Bypass Grafting.

Background: Off-pump coronary artery bypass grafting (OPCAB) is an alternative to on-pump coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). During OPCAB, the temporary use of an intracoronary shunt and inotropic medication or catecholamines should keep the central hemodynamics constant. Nevertheless, the need for conversion to on-pump CABG often occurs unexpectedly, most likely due to circulation instability. Circulation instability can appear first in peripheral body parts; therefore, peripheral microcirculation might serve as a predictor for the upcoming conversion to on-pump CABG. We investigated the impact of coronary artery ligation and shunt insertion during OPCAB on cutaneous microcirculation (cLDP) with Laser Doppler Perfusion Technology and transcutaneous oxygen partial pressure ( tcpO 2 ). Methods: In a pig model of OPCAB, peripheral circulation was evaluated after cLDP (N = 17) and tcpO 2 (N = 6) monitoring. Systolic, diastolic, and mean arterial pressure were also observed to prove the independence of perfusion measurement results from hemodynamic parameters. Results: Ligation time during cLDP and tcpO 2 monitoring were 101 ± 49 s and 83 ± 33 s, respectively. Shunt time was 11 ± 3 min during cLDP and 13 ± 2 min during tcpO 2 measurement. Ligation of the left anterior descending coronary artery (LAD) reduced cLDP significantly to 88 ± 14% (p = 0.007) and tcpO 2 to 71 ± 25% (p = 0.038). Inserting a temporary shunt into the LAD significantly improved cLDP (p = 0.006) and tcpO 2 (p = 0.015) compared to ligation. cLDP was restored to 99%, and tcpO 2 was restored to 91% of the baseline level before ligation. All hemodynamic parameters remained stable and did not change significantly during OPCAB. Conclusions: Although hemodynamic parameters stayed constant, peripheral microcirculation was influenced markedly during OPCAB. Inserting a temporary shut into the LAD leads to a complete normalization of peripheral microcirculation, regarding evaluation by cLDP and tcpO 2 .

HTK vs. HTK-N for Coronary Endothelial Protection during Hypothermic, Oxygenated Perfusion of Hearts Donated after Circulatory Death.

Protection of the coronary arteries during donor heart maintenance is pivotal to improve results and prevent the development of coronary allograft vasculopathy. The effect of hypothermic, oxygenated perfusion (HOP) with the traditional HTK and the novel HTK-N solution on the coronary microvasculature of donation-after-circulatory-death (DCD) hearts is known. However, the effect on the coronary macrovasculature is unknown. Thus, we maintained porcine DCD hearts by HOP with HTK or HTK-N for 4 h, followed by transplantation-equivalent reperfusion with blood for 2 h. Then, we removed the left anterior descending coronary artery (LAD) and compared the endothelial-dependent and -independent vasomotor function of both groups using bradykinin and sodium-nitroprusside (SNP). We also determined the transcriptome of LAD samples using microarrays. The endothelial-dependent relaxation was significantly better after HOP with HTK-N. The endothelial-independent relaxation was comparable between both groups. In total, 257 genes were expressed higher, and 668 genes were expressed lower in the HTK-N group. Upregulated genes/pathways were involved in endothelial and vascular smooth muscle cell preservation and heart development. Downregulated genes were related to ischemia/reperfusion injury, oxidative stress, mitochondrion organization, and immune reaction. The novel HTK-N solution preserves the endothelial function of DCD heart coronary arteries more effectively than traditional HTK.

Transcriptomic Changes in the Myocardium and Coronary Artery of Donation after Circulatory Death Hearts following Ex Vivo Machine Perfusion.

Donation after circulatory death (DCD) hearts are predominantly maintained by normothermic blood perfusion (NBP). Nevertheless, it was shown that hypothermic crystalloid perfusion (HCP) is superior to blood perfusion to recondition left ventricular (LV) contractility. However, transcriptomic changes in the myocardium and coronary artery in DCD hearts after HCP and NBP have not been investigated yet. In a pig model, DCD hearts were harvested and maintained for 4 h by NBP (DCD-BP group, N = 8) or HCP with oxygenated histidine-tryptophane-ketoglutarate (HTK) solution (DCD-HTK, N = 8) followed by reperfusion with fresh blood for 2 h. In the DCD group (N = 8), hearts underwent reperfusion immediately after procurement. In the control group (N = 7), no circulatory death was induced. We performed transcriptomics from LV myocardial and left anterior descending (LAD) samples using microarrays (25,470 genes). We applied the Boruta algorithm for variable selection to identify relevant genes. In the DCD-BP group, compared to DCD, six genes were regulated in the myocardium and 1915 genes were regulated in the LAD. In the DCD-HTK group, 259 genes were downregulated in the myocardium and 27 in the LAD; and 52 genes were upregulated in the myocardium and 765 in the LAD, compared to the DCD group. We identified seven genes of relevance for group identification: ITPRIP, G3BP1, ARRDC3, XPO6, NOP2, SPTSSA, and IL-6. NBP resulted in the upregulation of genes involved in mitochondrial calcium accumulation and ROS production, the reduction in microvascular endothelial sprouting, and inflammation. HCP resulted in the downregulation of genes involved in NF-κB-, STAT3-, and SASP-activation and inflammation.

Comparison of Extracellular Vesicles from Induced Pluripotent Stem Cell-Derived Brain Cells.

The pathophysiology of many neuropsychiatric disorders is still poorly understood. Identification of biomarkers for these diseases could benefit patients due to better classification and stratification. Exosomes excreted into the circulatory system can cross the blood-brain barrier and carry a cell type-specific set of molecules. Thus, exosomes are a source of potential biomarkers for many diseases, including neuropsychiatric disorders. Here, we investigated exosomal proteins produced from human-induced pluripotent stem cells (iPSCs) and iPSC-derived neural stem cells, neural progenitors, neurons, astrocytes, microglia-like cells, and brain capillary endothelial cells. Of the 31 exosome surface markers analyzed, a subset of biomarkers were significantly enriched in astrocytes (CD29, CD44, and CD49e), microglia-like cells (CD44), and neural stem cells (SSEA4). To identify molecular fingerprints associated with disease, circulating exosomes derived from healthy control (HC) individuals were compared against schizophrenia (SCZ) patients and late-onset Alzheimer's disease (LOAD) patients. A significant epitope pattern was identified for LOAD (CD1c and CD2) but not for SCZ compared to HC. Thus, analysis of cell type- and disease-specific exosome signatures of iPSC-derived cell cultures may provide a valuable model system to explore proteomic biomarkers for the identification of novel disease profiles.

Detailing the biomedical aspects of geroscience by molecular data and large-scale "deep" bioinformatics analyses.

As scientists investigated the molecular mechanisms of the biology of aging, they discovered that these are malleable and can enhance healthy longevity by intervening in the drivers of aging, which are leading to disease, dysfunction and death. These exciting observations gave birth to the field of geroscience. As the mechanisms of aging affect almost all mechanisms of life, detailed molecular mechanistic knowledge must be gained or expanded by considering and integrating as many types of data as possible, from genes and transcripts to socioenvironmental factors. Such a large-scale integration of large amounts of data will in turn profit from "deep" bioinformatics analyses that provide insights beyond contextualizing and interpreting the data in the light of knowledge from databases such as the Gene Ontology. The authors suggest that "deep" bioinformatics, employing methods based on artificial intelligence, will be a key ingredient of future analyses.

On frailty and accelerated aging during SARS-Cov-2: senescence.

The COVID-19 pandemic is a burden for the worldwide healthcare systems. Whereas a clear age-dependent mortality can be observed, especially multimorbid and frail persons are at an increased risk. As bio-functional rather than calendrical age is in the meanwhile known to play a crucial role for COVID-19-related outcomes, aging-associated risk factors, overall prognosis and physiological age-related changes should be systematically considered for clinical decision-making. In this overview, we focus on cellular senescence as a major factor of biological aging, associated with organ dysfunction and increased inflammation (inflammaging).

Sex-Specific Protection of Endothelial Function after Vascular Ischemia/Reperfusion Injury by the Senomorphic Agent Ruxolitinib.

Ischemia/reperfusion (I/R)-induced endothelial dysfunction occurs in various cardiovascular disorders. I/R injury is partially driven by the release of cytokines. Known for its use in senotherapy, the JAK inhibitor ruxolitinib is able to block the release of cytokines. We investigated the effect of ruxolitinib on the cytokine release and endothelial-dependent vasorelaxation in an in vitro model of I/R. Aortic segments of C57BL/6J mice (N = 12/group) were divided into three groups: control, in vitro I/R (I/R group), and in vitro I/R with ruxolitinib during ischemic incubation (I/R+Ruxo group). We determined cytokine expression. In organ bath chambers, we investigated the maximal endothelial-dependent relaxation to acetylcholine (RmaxACh) and maximal endothelial-independent relaxation to sodium-nitroprusside (RmaxSNP). RmaxACh was decreased in I/R compared to the control (83.6 ± 2.4 vs. 48.6 ± 3.4%; p < 0.05) and I/R+Ruxo (74.4 ± 2.6 vs. 48.6 ± 3.4%; p < 0.05). RmaxSNP was comparable between all groups. IL-10 was detectable only in I/R+Ruxo. CXCL5, CCL2, CCL3, CCL8, CCL11, ICAM-1, IL-1α, IL-7, TNF-α, and G-CSF were decreased or not detectable in I/R+Ruxo. In I/R+Ruxo, ICAM-1 was reduced in rings only from male mice. Treatment of the aorta from mice during in vitro ischemia with the senomorphic agent ruxolitinib reduces cytokine release and protects the endothelium from I/R-mediated dysfunction.

Improving Diastolic and Microvascular Function in Heart Transplantation with Donation after Circulatory Death.

The impact of the machine perfusion of donation after circulatory death (DCD) hearts with the novel Custodiol-N solution on diastolic and coronary microvascular dysfunction is unknown. Porcine DCD-hearts were maintained four hours by perfusion with normothermic blood (DCD-B), hypothermic Custodiol (DCD-C), or Custodiol-N (DCD-CN), followed by one hour of reperfusion with fresh blood, including microvascular and contractile evaluation. In another group (DCD group), one hour of reperfusion, including microvascular and contractile evaluation, was performed without a previous maintenance period (all groups N = 5). We measured diastolic function with a balloon catheter and microvascular perfusion by Laser-Doppler-Technology, resulting in Laser-Doppler-Perfusion (LDP). We performed immunohistochemical staining and gene expression analysis. The developed pressure was improved in DCD-C and DCD-CN. The diastolic pressure decrement (DCD-C: -1093 ± 97 mmHg/s; DCD-CN: -1703 ± 329 mmHg/s; DCD-B: -690 ± 97 mmHg/s; p < 0.05) and relative LDP (DCD-CN: 1.42 ± 0.12; DCD-C: 1.11 ± 0.13; DCD-B: 1.22 ± 0.27) were improved only in DCD-CN. In DCD-CN, the expression of eNOS increased, and ICAM and VCAM decreased. Only in DCD-B compared to DCD, the pathways involved in complement and coagulation cascades, focal adhesion, fluid shear stress, and the IL-6 and IL-17 pathways were upregulated. In conclusion, machine perfusion with Custodiol-N improves diastolic and microvascular function and preserves the microvascular endothelium of porcine DCD-hearts.

[Trial of the GeriNOT screening tool : Identification of geriatric risk potentials on admission to hospital care from the age of 70 years]. / Prüfung des Screening-Tools GeriNOT : Identifikation geriatrischer Risikopotenziale bei Aufnahme ab 70-Jähriger in die Krankenhausversorgung.

BACKGROUND: Geriatric-specific characteristics influence patient-relevant outcomes of inpatient hospital care in patients aged 70 years and older: prolonged length of stay, complications, increase in utilization of required services as well as mortality rates. OBJECTIVE: The screening tool GeriNOT, identification of geriatric risk potential with 7 items, of which mobility and cognition are double-weighted, score 9 points, was tested for its predictive content and diagnostic quality. MATERIAL AND METHODS: Diagnostic study from a retrospective, bicentric complete survey in all types of admission from 70 years with 2541 patient cases. Regression analyses in linked samples of the 7 items in GeriNOT and as noncombined end points: prolonged length of stay, complications, increase in need-based service at discharge and death. RESULTS: Mean age ± SD: 77.0 ± 6.4 years. ROC analyses report at a cut-off value calculated using the Youden index of ≥ 4 points in 2541 cases: increase in need-based service at discharge (AUC = 0.693, 95% CI = 0.663-0.723, sensitivity 75.2%, specificity 59.7%), complications (AUC = 0.662, 95% CI = 0.636-0.688, sensitivity 64.2%, specificity 61.6%) and death (AUC = 0.734, 95% CI = 0.682-0.786, sensitivity 76.4%, specificity 57.5%). Possibly suitable for use as screening to identify geriatric risk potentials at a cut-off of ≥ 4 points. DISCUSSION: Provide an initial filter screening with regard to mobility. Such identification could provide the involved persons with the opportunity for an improved treatment outcome by adapting the inpatient process. Prospective validation of GeriNOT needed.

[Strengthening prevention and health promotion in and for old age]. / Prävention und Gesundheitsförderung im und für das Alter stärken.

BACKGROUND: Disease prevention and health promotion in and for old age have become increasingly more important. Nevertheless, more (national) research and implementation in practice is needed, as the international comparison shows. OBJECTIVE: To develop guiding principles for research and practice on prevention and health promotion in and for old age. MATERIAL AND METHODS: As part of an iterative process, members of the German Society of Gerontology and Geriatrics came together in workshops and symposia to formulate key guiding principles and fields of action for prevention and health promotion. RESULTS: The following were worked out: 1) prevention and health promotion are useful and possible up to oldest age, 2) prevention and health promotion for advanced age should start early, 3) prevention and health promotion must take into account the diversity and heterogeneity of the life situations of old people, 4) prevention and health promotion promote and demand self-determination and participation, 5) prevention of multiple illnesses must be given greater attention, 6) prevention of the need for long-term care and prevention in long-term care must be treated equally, 7) prevention and health promotion must be thought of in terms of life worlds and across sectors, paying particular attention to aspects of social inequality and a focus on resources, 8) prevention and health promotion and the related research must be interdisciplinary and transdisciplinary and be applied at different levels, from molecular to societal. DISCUSSION: The guiding principles outline the focal points of future-oriented ageing, health and healthcare research and open up fields of action but also show the limits of this approach for political decision-makers, researchers and practitioners.

Cardiovascular risk factors, living and ageing in Halle: the CARLA study.

The CARLA study (Cardiovascular Disease, Living and Ageing in Halle) is a longitudinal population-based cohort study of the general population of the city of Halle (Saale), Germany. The primary aim of the cohort was to investigate risk factors for cardiovascular diseases based on comprehensive cardiological phenotyping of study participants and was extended to study factors associated with healthy ageing. In total, 1779 probands (812 women and 967 men, aged 45-83 years) were examined at baseline (2002-2005), with a first and second follow-up performed 4 and 8 years later. The response proportion at baseline was 64.1% and the reparticipation proportion for the first and second follow-up was 86% and 77% respectively. Sixty-four percent of the study participants were in retirement while 25% were full- or partially-employed and 11% were unemployed at the time of the baseline examination. The currently running third follow-up focuses on the assessment of physical and mental health, with an intensive 4 h examination program, including measurement of cardiovascular, neurocognitive, balance and gait parameters. The data collected in the CARLA Study resulted in answering various research questions in over 80 publications, of which two thirds were pooled analyses with other similar population-based studies. Due to the extensiveness of information on risk factors, subclinical conditions and evident diseases, the biobanking concept for the biosamples, the cohort representativeness of an elderly population, and the high level of quality assurance, the CARLA cohort offers a unique platform for further research on important indicators for healthy ageing.

The relationship of skin autofluorescence with diastolic function and HFA-PEFF score in a general population of older people.

BACKGROUND AND AIMS: Advanced glycation end-products accumulation in tissue as measured by Skin autofluorescence (SAF) is related to diastolic function in specific patient populations. This analysis aims at investigating this relationship in a general population of older persons. METHODS AND RESULTS: Based on data from the CARLA cohort at first follow-up, 245 subjects were analyzed and stratified according to cardiovascular risk factors (CVRF). We used linear regression to investigate the association between diastolic function evaluated by echocardiography, HFA-PEFF score, and SAF. Univariable regression analysis showed an association of SAF with septal-E/e' (standardised beta = 1.11, 95% CI = 0.51-1.71) and A (3.42, 95% CI = 0.72-6.12), the former persisting after adjustment for age, sex and CVRF (0.67, 95% CI = 0.05-1.28). Septal-E/e' remained related to SAF only in the high cardiovascular risk stratum (1.16, 95% CI = 0.26-2.06). SAF was related to HFA-PEFF score (0.27, 95% CI = 0.10-0.43) but not after correcting for age and sex (0.16, 95% CI = 0.00-0.32) and CVRF and glomerular filtration rate (0.12, 95% CI = -0.07 - 0.27). SAF was related to the HFA-PEFF score only for participants with high cardiovascular risk (0.23, 95% CI = 0.02-0.45). CONCLUSION: In a general community-dwelling older population, SAF is related to diastolic function as measured by septal-E/e'. Further research is necessary to assess if SAF is a potential screening tool for diastolic dysfunction in advanced age.

How Justified is the Assumption of Programmed Aging in Reminiscence of Weismann's Theories?

Theories about the benefits of death and the resulting increased likelihood of programmed aging are controversial, advocated only by a minority. The extent to which their assumptions might be justified should be investigated. To this end, various approaches to the possible utility or origin were considered, particularly potential benefits of the faster generational change caused by possible evolutionary compound interest. Reference was made to the thinking of Weismann, the father of regulated aging theories, who advocated non-adaptive concepts at the end of his career. In a thought experiment, circadian rhythms are discussed as a possible molecular source of aging regulation.

[Aging of the immune system]. / Alterung des Immunsystems.

With increasing age a rise in the incidence of infections, inflammatory diseases such as arteriosclerosis and tumors and simultaneously a reduction in the success of vaccinations can be observed. A dysfunctional immune system is responsible for this. The immune system can be divided into three domains. The first barrier, the epithelioid protective barrier of the skin and the mucosa, loses its protective function with age. The second barrier, the innate immune system, is characterized in old age by chronic low-grade inflammation and a simultaneous reduction of an adequate response to pathogens. The reduced hematopoiesis of new naïve lymphocytes and a reduction of diversity describe the adaptive immune system, the third barrier at old age. These changes, summarized as immunosenescence, are partly responsible for many degenerative diseases.

[Biological mechanisms of aging in the cardiovascular system]. / Biologische Alterungsmechanismen im Herz-Kreislauf-System.

Cardiovascular diseases, which are at the end of a spectrum of degenerative processes, are one of the leading causes of death worldwide. A causal contribution to these and many other diseases is made by key biological aging mechanisms that have been summarized as the hallmarks of aging. These include accumulation of macromolecular damage, epigenetic changes, impaired proteostasis, telomere shortening, mitochondrial dysfunction, cellular senescence, inflammatory reactions, altered metabolism, impaired cellular communication and changes in the stem cell niche. In the cardiovascular system, oxidative and glycative stress are particularly important as sources of macromolecular damage. These induced insidious changes reduce the resilience and resistance of the heart and vessels to stress, ultimately leading to functional impairments and diseases. A possible novel approach, which does not aim at an intervention against the classical cardiovascular diseases but against the hallmarks of aging, and is termed geroscience, provides valuable concepts but still has to prove itself in the future.

Simultaneous influence of sex and age on blood pressure difference between supine and sitting body positions.

OBJECTIVES: Doctors' offices and outpatient departments typically measure blood pressure (BP) with the patient in a sitting position, whereas inpatient departments also use the supine position. As sex and age influence the autonomic function associated with BP regulation our study compared BP measurements in supine and sitting positions for men and women of different ages. METHODS: We included 91 men and 118 women (≥18 years) without severe diseases. Hypertension was not an exclusion criterion because it is common in older persons. Mean left brachial BP and heart rate were determined by a digital sphygmomanometer in supine position as well as in sitting position before and after hand force measurement. RESULTS: In a supine position women had slightly lower diastolic BP values than men. After sitting up, the diastolic BP increased in nearly all subjects. This increase was greater in women older than 50 years than for aged-matched men. In contrast to diastolic BP the systolic BP increased after sitting up in only two thirds of the subjects. Especially in women younger than 50 years the systolic BP often did not increase but decreased in response to postural change. The pulse pressure was mostly reduced after sitting up. This reduction was more pronounced in women than men independent of age and physical effort (i.e. hand force measurement). The sitting position also caused an increased heart rate, which was independent of sex and age. CONCLUSION: Postural changes in the systolic and diastolic BP simultaneously depend on sex and age that needs to be considered for BP measurements in supine and sitting body positions.

Correction to: Severe but not moderate hyperoxia of newborn mice causes an emphysematous lung phenotype in adulthood without persisting oxidative stress and inflammation.

Following publication of the original article [1], the authors flagged that the article had published with an error in 'Table 1'.

Carbohydrates in nutrition: friend or foe?

Fats, proteins and carbohydrates are the main energy supplies in human nutrition. The ratio of these three has often been discussed within the nutritional sciences over the years. Carbohydrates were important for our ancestors since many carbohydrate-rich foods were easily storable without cooling in comparison to protein-rich or fat-rich food, such as meat or fish. While humans consumed a mostly low-calorie nutrition and experienced seasonal changes in food availability and abundance for a long time, food supply changed in the last 100 years. We are now living in abundance, leading to a drastic increase in man-made and chronic diseases, such as diabetes mellitus. High, unregulated blood sugar levels in combination with the accumulation of advanced glycation end products seem to be major causes for the development of diabetes. Therefore, it is under discussion how healthy carbohydrates are and if they have to be avoided in nutrition.

Receptor for advanced glycation end-products modulates lung development and lung sensitivity to hyperoxic injury in newborn mice.

The receptor for advanced glycation end-products is mainly expressed in type I alveolar epithelial cells but its importance in lung development and response to neonatal hyperoxia is unclear. Therefore, our study aimed at the analysis of young wildtype and RAGE knockout mice which grew up under normoxic or hyperoxic air conditions for the first 14 days followed by a longer period of normoxic conditions. Lung histology, expression of lung-specific proteins, and respiratory mechanics were analyzed when the mice reached an age of 2 or 4 months. These analyses indicated less but larger and thicker alveoli in RAGE knockout mice, reverse differences in the mRNA and protein amount of pro-surfactant proteins (pro-SP-B, pro-SP-C) and aquaporin-5, and differences in the amount of elastin and CREB, a pro-survival transcription factor, as well as higher lung compliance. Despite this potential disadvantages, RAGE knockout lungs showed less long-term damages mediated by neonatal hyperoxia. In detail, the hyperoxia-mediated reduction in alveoli, enlargement of airspaces, fragmentation of elastic fibers, and increased lung compliance combined with reduced peak airflows was less pronounced in RAGE knockout mice. In conclusion, RAGE supports the alveolarization but makes the lung more susceptible to hyperoxic injury shortly after birth. Blocking RAGE function could still be a helpful tool in reducing hyperoxia-mediated lung pathologies during alveolarization.

Advanced glycation end products and their ratio to soluble receptor are associated with limitations in physical functioning only in women: results from the CARLA cohort.

BACKGROUND: Advanced glycation end products (AGEs), modifications of proteins or amino acids, are increasingly produced and accumulated with age-related diseases. Recent studies suggested that the ratio of AGEs and their soluble receptor (sRAGE) is a more accurate biomarker for age-related diseases than each separately. We aim to investigate whether this also applies for physical functioning in a broad age-spectrum. METHODS: AGE and sRAGE levels, and physical functioning (SF-12 questionnaire) of 967 men and 812 women (45-83 years) were measured in the CARLA study. We used ordinal logistic regression to examine associations between AGEs, sRAGE, and AGE/sRAGE ratio with physical functioning in sex- and age-stratified models. RESULTS: Higher levels of AGEs and AGE/sRAGE ratio were associated with lower physical functioning only in women, even after consideration of classical lifestyle and age-related factors (education, BMI, smoking, alcohol consumption, diet, creatinine clearance, diabetes mellitus, lipid lowering and antihypertensive drugs) (odds ratio (OR) =0.86, 95%confidence interval = 0.74-0.98 and OR = 0.86, 95%CI = 0.75-0.98 for AGEs and AGE/sRAGE ratio respectively). We could not demonstrate a significant difference across age. CONCLUSIONS: We showed a sex-specific association between physical functioning and AGEs and AGE/sRAGE, but no stronger associations of the latter with physical functioning. Further investigation is needed in the pathophysiology of this association.