Two randomized placebo-controlled double-blind paralleled trials (42 men in Lyon, 19 women in Lausanne) were designed to test 2 g/day of a grape polyphenol extract during 31 days of high calorie-high ...fructose overfeeding. Hyperinsulinemic-euglycemic clamps and test meals with 1,1,1-
C
-triolein were performed before and at the end of the intervention. Changes in body composition were assessed by dual-energy X-ray absorptiometry (DEXA). Fat volumes of the abdominal region and liver fat content were determined in men only, using 3D-magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) at 3T. Adipocyte's size was measured in subcutaneous fat biopsies. Bodyweight and fat mass increased during overfeeding, in men and in women. While whole body insulin sensitivity did not change, homeostasis model assessment of insulin resistance (HOMA-IR) and the hepatic insulin resistance index (HIR) increased during overfeeding. Liver fat increased in men. However, grape polyphenol supplementation did not modify the metabolic and anthropometric parameters or counteract the changes during overfeeding, neither in men nor in women. Polyphenol intake was associated with a reduction in adipocyte size in women femoral fat. Grape polyphenol supplementation did not counteract the moderated metabolic alterations induced by one month of high calorie-high fructose overfeeding in men and women. The clinical trials are registered under the numbers NCT02145780 and NCT02225457 at ClinicalTrials.gov and available at https://clinicaltrials.gov/ct2/show/NCT02145780 and https://clinicaltrials.gov/ct2/show/NCT02225457.
AIM： To explore the influence of polymorphisms in genes encoding for the chemokines Stromal cell-Derived Factor-1 （SDF-1）/CXCL12 and Monocyte Chemotactic Protein-1 （MCP-1）/CCL2, or for the chemokine ...receptor CCR5 on the risks of liver-related death and hepatocellular carcinoma （HCC） occurrence in hepatitis C virus （HCV）-infected patients.
METHODS： SDF-1 3＇A, MCP-1 （-2518） and CCRS-△32 polymorphisms, SDF-1α, Regulated upon Activation Normal T cells Expressed and Secreted （RANTES）/CCL5 and MCP-1 serum levels were determined in 120 HCV- infected patients, included at time of cirrhosis diagnosis and prospectively followed-up.
RESULTS： During follow-up, 23/120 （19.1%） patients died and 47/120 （39.1%） developed HCC. Carriers and noncarriers of each genetic marker had similar baseline characteristics estimating the severity of liver disease. The occurrence of death or HCC during follow-up was similar among carriers and noncarriers of each polymorphism. There was no association between the carriage of mutated alleles and chemokine serum levels and the latter were not associated with the risks of death or HCC.
CONCLUSION： This study suggests the lack of association of SDF-1 3＇A, MCP-1 （-2518）, CCRS-△32 polymorphisms with death and HCC occurrence in cirrhotic HCV-infected patients.
In the middle-aged, it has been shown that moderate physical activity is associated with increased global HR variability (HRV) and vagal-related HRV indexes. However, the relative effect of quantity ...and intensity of physical activity on HRV is still unknown. The purpose of this study was to compare HRV indexes in three groups of subjects presenting different long-term physical activity profiles: sedentary subjects (SED) with low-energy expenditure (PAEE) and two groups of subjects with equivalent moderate PAEE, but differing in terms of intensity of physical activity (active (ACT) and sportive (SP) individuals).
Forty-three middle-aged subjects (61.2 +/- 4.3 yr) were divided into the three groups on the basis of a physical activity questionnaire (Modified Baecke Questionnaire for Older Adults). Physical activity was evaluated by accelerometry for 1 wk. Time and frequency domain HRV indexes were determined during quiet periods in the morning on 5-min stationary R-R interval segments under controlled breathing. Quality of life was evaluated using the SF-36 Health Survey Questionnaire.
SP spent more time in moderate to very high activities than ACT (2.1 +/- 0.1 vs 0.6 +/- 0.1 h.wk(-1); P < 0.05) and less time in very light to light activities (62.8 +/- 2.0 vs 73.7 +/- 1.7 h.wk(-1); P < 0.05). SP presented higher vagal-related HRV indexes than SED (P < 0.05), whereas increases in ACT were less marked. ACT and SP had similar health status scores, which were higher than for SED (P < 0.05).
In older adults with different lifestyles, habitual moderate PAEE is associated with better self-estimated overall health status and higher vagal-related HRV indexes compared with subjects with low PAEE, especially when moderate- to very high-intensity physical activities are undertaken.
Background: Research on the associations between walking and cycling with obesity-related phenotypes is growing but relies mostly on the use of BMI. The purpose of this study was to analyze ...associations of walking and cycling behaviors assessed separately with various obesity markers in French adults. Methods: In 12,776 adult participants (71.3% women) of the on-going NutriNet Santé web-cohort, we assessed by self-report past-month walking and cycling (for commuting, errands and leisure), and obesity measures were taken during a visit at a clinical center (weight, height, waist circumference, and percent body fat by bioimpedance). Results: In analyses not taking into account other types of physical activity (household, leisure), walking more than 2.5 h/week was associated in women with lower weight (-1.8 kg), waist circumference (-1.7 cm) and percent body fat (-1.1%) (all p < 0.001). Cycling more than 1.5 h/week was associated in men and women with lower weight (-4.3 and -1.4 kg, respectively), waist circumference (-4.4 and -2.1 cm, respectively), and percent body fat (-2.5 and -1.9 % respectively) (all p < 0.001). Results were unaltered when analyses were further adjusted on household and leisure physical activity. Conclusion: These results show important differences between walking and cycling in their association with obesity markers in men and women. These findings provide some evidence for the need to consider separately walking and cycling when designing public health measures for prevention of obesity in adults.
Ultradian rhythmicity appears to be characteristic of several endocrine systems. As described for other hormones, insulin release is a multioscillatory process with rapid pulses of about 10 min and ...slower ultradian oscillations (50--120 min). The mechanisms underlying the ultradian circhoral oscillations of insulin secretion rate (ISR), which arise in part from a rhythmic amplification of the rapid pulses, are not fully understood. In humans, included in the same period range is the alternation of rapid eye movement (REM) and non-REM (NREM) sleep cycles and the associated opposite oscillations in sympathovagal balance. During sleep, the glucose and ISR oscillations were amplified by about 150%, but the REM-NREM sleep cycles did not entrain the glucose and ISR ultradian oscillations. Also, the latter were not related to either the ultradian oscillations in sympathoagal balance, as inferred from spectral analysis of cardiac R-R intervals, or the plasma fluctuations of glucagon-like peptide-1 (GLP-1), an incretin hormone known to potentiate glucose-stimulated insulin. Other rhythmic physiological processes are currently being examined in relation to ultradian insulin release.
Objective: We investigate the relationship between changes in heart rate variability and electroencephalographic (EEG) activity during sleep.
Method: Nine male subjects with regular non-rapid-eye ...movement-rapid-eye movement (NREM-REM) sleep cycles were included in the study. They underwent EEG and cardiac recordings during one experimental night. Heart rate variability was determined over 5-min periods by the ratio of low frequency to low frequency plus high frequency power LF/(LF+HF) calculated using spectral analysis of R-R intervals. EEG spectra were analyzed using a fast Fourier transform algorithm.
Results: We found an ultradian 80–120 min rhythm in the LF/(LF+HF) ratio, with high levels during rapid eye movement (REM) sleep and low levels during slow wave sleep (SWS). During sleep stage 2 there was a progressive decrease in the transition from REM sleep to SWS, and an abrupt increase from SWS to REM sleep. These oscillations were significantly coupled in a ‘mirror-image’ to the overnight oscillations in delta wave activity, which reflect sleep deepening and lightening. Cardiac changes preceded EEG changes by about 5 min.
Conclusions: These findings demonstrate the existence of an inverse coupling between oscillations in delta wave activity and heart rate variability. They indicate a non-uniformity in sleep stage 2 that underlies ultradian sleep regulation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Laboratoire des Régulations Physiologiques et des Rythmes
Biologiques chez l'Homme, Institut de Physiologie, 67085 Strasbourg Cedex, France
We have recently demonstrated that the overnight
profiles ...of cardiac interbeat autocorrelation coefficient of R-R
intervals ( r RR )
calculated at 1-min intervals are related to the changes in sleep
electroencephalographic (EEG) mean frequency, which reflect depth of
sleep. Other quantitative measures of the Poincaré plots, i.e.,
the standard deviation of normal R-R intervals (SDNN) and the root mean
square difference among successive R-R normal intervals (RMSSD), are
commonly used to evaluate heart rate variability. The present study was
designed to compare the nocturnal profiles of
r RR , SDNN, and
RMSSD with the R-R spectral power components: high-frequency (HF)
power, reflecting parasympathetic activity; low-frequency (LF) power,
reflecting a predominance of sympathetic activity with a
parasympathetic component; and the LF-to-HF ratio (LF/HF), regarded as
an index of sympathovagal balance.
r RR , SDNN, RMSSD,
and the spectral power components were calculated every 5 min during
sleep in 15 healthy subjects. The overnight profiles of
r RR and LF/HF
showed coordinate variations with highly significant correlation
coefficients ( P < 0.001 in all
subjects). SDNN correlated with LF power
( P < 0.001), and RMSSD correlated
with HF power ( P < 0.001). The
overnight profiles of
r RR and EEG mean
frequency were found to be closely related with highly cross-correlated coefficients ( P < 0.001). SDNN and
EEG mean frequency were also highly cross correlated
( P < 0.001 in all subjects but 1).
No systematic relationship was found between RMSSD and EEG mean
frequency. In conclusion,
r RR appears to be
a new tool for evaluating the dynamic beat-to-beat interval behavior
and the sympathovagal balance continuously during sleep. This nonlinear
method may provide new insight into autonomic disorders.
Poincaré plot; electroencephalographic spectral
analysis
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