P2251Association between low-grade inflammation, metabolic factors, vascular biomarkers and gut microbiota in different age groups

Background

Despite the growing interest to the theme, the gut microbiota (GM) composition and functional capacity in relation to cardiovascular diseases (CVD) have been poorly studied. It is not well studied in nonagenarians or centenarians who live much longer than others with postponed CVD. In this study, we assessed GM in association with different metabolic factors in healthy middle-aged adults and the elderly at the turn of a hundred years old.

Purpose

Our aim was to study GM in a healthy cohort (HC) with different metabolic risk factors and in an extremely elderly cohort (EC) of long livers from our city.

Methods

The study included HC of 104 untreated subjects aged from 25–76y (52±13) carefully selected through the exclusion of CVD and other chronic diseases by means of clinical (with different specialists consultations to exclude any factors of inflammation) and a wide range of laboratory evaluation, ECG, treadmill test, ECHOCG, carotid artery ultrasound and the second group of 20 long livers 97–100y (98±1). EC underwent a complex geriatric assessment, also a wide range of laboratory evaluation, ECG, ECHOCG, carotid artery ultrasound. GM composition was studied by the V3-V4 16S rRNA sequencing. Taxonomic units were identified with QIIME 1.9.1. Statistical analysis was done by using the Phyton v.3.2 programming language. Metabolic reconstruction was performed with PICRUSt algorithm. All GM analyzes performed with age, sex and FDR adjustments.

Results

One of the most pronounced differences in GM between groups was a significantly higher representation of antiinflammatory Bifidobacterium genus in long livers (p=0.026 (MaAsLin), LDA=4.304). Among risk factors, high body mass index (BMI) was associated with a high abundance of conditional pathogens of Prevotella genus in HC (p<0.002, GLM) and also in EC (p=0.013, MaAsLin). BMI was correlated with hs-CRP level in EC (p=0.04, rs = 0.634). Median hsCRP in EC was 2.4mg/l (Q3–Q1=5.58), 2.45mg/l (Q3–Q1=2.03) (no significant differences, U-test). Despite this, we found that microbiota of long livers had much higher potential to produce butyrate (anti-inflammatory agent, p=0.016 (MaAsLin), LDA=3.345, PICRUSt algorithm). Average intima-media thickness (IMT) in EC was 1.07±0.16mm, and 0.76±0.2mm in HC, the difference was not significant (p=0.37, t-test). We found the association between the IMT with Serratia (gram negative conditional pathogens) abundance (p=0.009) in HC but not in EC.

Butyrate synthesis potential in EC vs HC

Conclusions

The EC were unexpectedly healthy. Considering the GM analysis, we may propose that EC microbiota protected long livers from the low-grade inflammation and thus protected them from the development of metabolic disorders by producing a high amount of butyrate, one of the most important anti-inflammatory agents in the human body. Conditional pathogens (the inflammation initiators) associated with BMI and IMT as well as butyrate producers may subsequently become a target for cardiovascular prevention.

Acknowledgement/Funding

Governmental support

[Thrombosis in patients with malignancy]

Thrombosis traditionally considered as a complication of cardiovascular disease, however, this problem until recently was rarely taken into account in the presence of cancer. Although the association between cancer and thrombosis has been known almost 150 years ago, awareness of the impact of thrombotic complications have increased only now. Cancer is an independent major risk factor for venous thromboembolism (VTE), which is the leading cause of death of cancer patient. The incidence of VTE is steadily increasing in these patients. Thrombotic events have a significant impact on the quality of life of patients, and are associated with worsening of their short-term and long-term survival. The objective of this review is to summarize modern views on pathophysiology, as well as to outline new approaches to risk assessment, prevention and treatment of thrombosis in cancer patients.

Growth Hormone, Insulin-Like Growth Factor-1, Insulin Resistance, and Leukocyte Telomere Length as Determinants of Arterial Aging in Subjects Free of Cardiovascular Diseases

Background: Increased arterial stiffness (AS), intima-media thickness (IMT), and the presence of atherosclerotic plaques (PP) have been considered as important aspects of vascular aging. It is well documented that the cardiovascular system is an important target organ for growth hormone (GH) and insulin-like growth factor (IGF)-1 in humans, and GH /IGF-1 deficiency significantly increases the risk for cardiovascular diseases (CVD). The telomere length of peripheral blood leukocytes (LTL) is a biomarker of cellular senescence and that has been proposed as an independent predictor of (CVD). The aim of this study is to determine the role of GH/IGF-1, LTL and their interaction cardiovascular risk factors (CVRF) in the vascular aging. Methods: The study group included 303 ambulatory participants free of known CVD (104 males and 199 females) with a mean age of 51.8 ± 13.3 years. All subjects had one or more CVRF [age, smoking, arterial hypertension, obesity, dyslipidemia, fasting hyperglycemia, insulin resistance-HOMA (homeostatic model assessment) >2.5, or high glycated hemoglobin]. The study sample was divided into the two groups according to age as "younger" (m ≤ 45 years, f ≤ 55 years) and "older" (m > 45 years, f > 55 years). IMT and PP were determined by ultrasonography, AS was determined by measuring the carotid-femoral pulse wave velocity (c-f PWV) using the SphygmoCor system (AtCor Medical). LTL was determined by PCR. Serum IGF-1 and GH concentrations we measured by immunochemiluminescence analysis. Results: Multiple linear regression analysis with adjustment for CVRF indicated that HOMA, GH, IGF-1, and LTL had an independent relationship with all the arterial wall parameters investigated in the younger group. In the model with c-f PWV as a dependent variable, p < 0.001 for HOMA, p = 0.03 for GH, and p = 0.004 for LTL. In the model with IMT as a dependent variable, p = 0.0001 for HOMA, p = 0.044 for GH, and p = 0.004 for IGF-1. In the model with the number of plaques as a dependent variable, p = 0.0001 for HOMA, and p = 0.045 for IGF-1. In the older group, there were no independent significant associations between GH/IGF-1, LTL, HOMA, and arterial wall characteristics. Conclusions: GH/IGF-1, IR, HOMA, and LTL were the important parameters of arterial aging in younger healthy participants.

Atorvastatin Therapy Modulates Telomerase Activity in Patients Free of Atherosclerotic Cardiovascular Diseases

Background: Telomerase activity (TA) is considered as the biomarker for cardiovascular aging and cardiovascular diseases (CVDs). Recent studies suggest a link between statins and telomere biology that may be explained by anti-inflammatory actions of statins and their positive effect on TA. Until now, this effect has not been investigated in prospective randomized studies. We hypothesized that 12 months of atorvastatin therapy increased TA in peripheral blood mononuclear cells. Methods: In a randomized, placebo-controlled study 100 hypercholesterolemic patients, aged 35-75 years, free of known CVDs and diabetes mellitus type 2 received 20 mg of atorvastatin daily or placebo for 12 months. TA was measured by quantitative polymerase chain reaction. Results: At study end, 82 patients had sufficient peripheral blood mononuclear cells needed for longitudinal analysis. TA expressed as natural logarithms changed from 0.46 ± 0.05 to 0.68 ± 0.06 (p = 0.004) in the atorvastatin group and from 0.67 ± 0.06 to 0.60 ± 0.07 (p = 0.477) in the control group. In multiple regression analysis, atorvastatin therapy was the only independent predictor (p = 0.05) of the changes in TA independently of markers of chronic inflammation and oxidative stress. Atorvastatin therapy was associated with increases in interleukin-6 within the normal range and a tendency toward reduction in blood urea. Conclusion: These initial observations suggest atorvastatin can act as telomerase activator and potentially as effective geroprotector. Trial registration: The trial was registered in ISRCTN registry ISRCTN55050065.

[The age-related changes of the heart rate variability measurements: the role of the inflammation, oxidative stress and telomeres biology]

The autonomic and central nervous system, a number of humoral and reflex effects regulate the heart rate. The main role in the heart rate regulation belongs to the autonomic nervous system. A common method for studying the autonomic influences on the heart rate is the analysis of heart rate variability (HRV), which allows to evaluate the neuro-vegetative status of the organism, determine its adaptive capacity, to evaluate the level of stress and the degree of tension of regulatory systems. An age-related decrease of HRV measurements in healthy people reflects the weakening of the autonomic regulation of cardiac activity. The most pronounced changes are found in patients older than 60 years. The HRV depression is preceded by hemodynamic and metabolic disorders is associated with high cardiovascular risk and is a predictor of life-threatening arrhythmias and sudden death in the elderly.The reasons for HRV changes with age stay unclear. In the light of modern ideas about the mechanisms of aging, several complementary theories proposed. Telomere shortening, the role of oxidative stress and inflammation as possible mechanisms of age-related changes in the autonomic regulation of the heart rhythm, will be discussed in this article.

[Association of renal function, telomere length and markers of chronic inflammation for patients without chronic kidney and cardiovascular diseases]

Most of people over 60 years of age have decreased renal function and the velocity of glomerular filtration rate reduction varies greatly. Presumably, one of the probable mechanisms of accelerated decline of renal function may be a shortening of telomere length due to chronic inflammation. The main purpose of research was to appreciate the association of renal function, leukocytes telomeres length and markers of chronic inflammation in patients without chronic kidney disease and cardiovascular disease. 253 patients without chronic kidney diseases and cardiovascular diseases were included in the study. The average age of patients was 51,5±13,3 years. There were 172 women and 81 men. 55 patients had hypertension of 1-2 degree, 46 patients had normal renal function, 207 had mild failure of kidney function. Albuminuria was < 30 mg/day in all patients. Multivariate linear regression analysis revealed statistically significant correlation between albuminuria level and telomere length (p=0,023), C reactive protein (p=0,047) and fibrinogen (p=0,001). Glomerular filtration rate, urea and creatinine were not associated with telomere length and markers of inflammation but were correlated well with age, p < 0,001.

CONCLUSIONS

Albuminuria is mainly associated with chronic inflammation and telomere length (from all studied indices of renal function). Albuminuria may be regarded as a marker of replicative cell senescence and a therapeutic target for the prevention of renal function reduction.

[Age-related Changes of Left Ventricular Diastolic Function, NT-proBNP Level and Their Association with Leukocyte Telomere Length]

With advancing age the left ventricle (LV) undergoes structural and functional changes, thereby creating the substrate for the development of diseases. One possible mechanism of the ageing of the heart is cellular senescence. Leukocyte telomere length (LTL) is a marker of replicative ageing. The purpose of this study was to evaluate the diastolic function of LV and level of NT-proBNP in people of different ages free of cardiovascular diseases and to assess their relationship with LTL. Our data showed that old age is associated with diastolic dysfunction and increase in the levels of NT-proBNP. The group of older subjects had lower values of E/A (0.96+/-0.036 vs 1.27+/-0.03, p<0.001), Em/Am (0.9+/-0.035 vs 1.5+/-0.066) and higher values of IVRT (81+/-1.56 vs 70+/-1.23 s, p<0.001), DT (198+/-3.98 vs 175+/-2.82 s, p<0.001), that reflected impairment of LV relaxation. NT-proBNP level was higher in the elderly (100.82+/-7.1 vs 48.47+/-6.7 g/ml, p<0.01), but it did not correlate with LTL. The most sensitive to the age parameters of LV diastolic function (E/A and Em/Am ratio) were positively and independently of age associated with LTL (p<0.001). Older individuals with shorter LTL had significantly lower values of E/A ratio.

CONCLUSION

Telomere length appears to be a biomarker of myocardium ageing.

[Age-related Changes of Left Ventricular Diastolic Function, NT-proBNP Level and Their Association With Leukocyte Telomere Length]

With advancing age the left ventricle (LV) undergoes structural and functional changes, thereby creating the substrate for the development of diseases. One possible mechanism of the ageing of the heart is cellular senescence. Leukocyte telomere length (LTL) is a marker of replicative ageing. The purpose of this study was to evaluate the diastolic function of LV and level of NT-proBNP in people of different ages free of cardiovascular diseases and to assess their relationship with LTL. Our data showed that old age is associated with diastolic dysfunction and increase in the levels of NT-proBNP. The group of older subjects had lower values of E/A (0.96 ± 0.036 vs 1.27 ± 0.03, p < 0.001), Em/Am (0.9 ± 0.035 vs 1.5 ± 0.066) and higher values of IVRT (81 ± 1.56 vs 70 ± 1.23 MS, p < 0.001), DT (198 ± 3.98 vs 175 ± 2.82 MS, p < 0.001), that reflected impairment of LV relaxation. NT-proBNP level was higher in the elderly (100.82 ± 7.1 vs 48.47 ± 6.7 ωg/ml, p < 0.01), but it did not correlate with LTL. The most sensitive to the age parameters of LV diastolic function (E/A and Em/Am ratio) were positively and independently of age associated with LTL (p < 0.001). Older individuals with shorter LTL had significantly lower values of E/A ratio.

CONCLUSION

Telomere length appears to be a biomarker of myocardium ageing.