Brachial-ankle pulse wave velocity (baPWV) is a promising technique to assess arterial stiffness conveniently. However, it is not known whether baPWV is associated with well-established indices of central arterial stiffness. We determined the relation of baPWV with aortic (carotid-femoral) PWV, leg (femoral-ankle) PWV, and carotid augmentation index (AI) by using both cross-sectional and interventional approaches. First, we studied 409 healthy adults aged 18-76 years. baPWV correlated significantly with aortic PWV (r ¼ 0.76), leg PWV (r ¼ 0.76), and carotid AI (r ¼ 0.52). A stepwise regression analysis revealed that aortic PWV was the primary independent correlate of baPWV, explaining 58% of the total variance in baPWV. Additional 23% of the variance was explained by leg PWV. Second, 13 sedentary healthy men were studied before and after a 16-week moderate aerobic exercise intervention (brisk walking to jogging; 30-45 min/day; 4-5 days/week). Reductions in aortic PWV observed with the exercise intervention were significantly and positively associated with the corresponding changes in baPWV (r ¼ 0.74). A stepwise regression analysis revealed that changes in aortic PWV were the only independent correlate of changes in baPWV (b ¼ 0.74), explaining 55% of the total variance. These results suggest that baPWV may provide qualitatively similar information to those derived from central arterial stiffness although some portions of baPWV may be determined by peripheral arterial stiffness.
Muscle cross-sectional area of the quadriceps femoris (CSAQF), maximal isometric strength (handgrip test and unilateral knee extension/flexion), the shape of isometric force-time curves, and power-load curves during concentric and stretch-shortening cycle (SSC) actions with loads ranging from 15 to 70% of one repetition maximum half-squat (1RMHS) and bench-press (1RMBP) were examined in 26 middle-aged men in the 40-year-old (M40) (mean age 42, range 35-46) and 21 elderly men in the 65-year-old age group (M65) (mean age 65, range 60-74). Maximal bilateral concentric (1RMHS and 1RMBP), unilateral knee extension (isometric; MIFKE and concentric; 1RMKE) strength and muscle CSA in M65 were lower (P < 0.001) than in M40. The individual values of the CSAQF correlated with the individual values of maximal concentric 1RMHS, 1RMKE and MIFKE in M65, while the corresponding correlations were lower in M40. The maximal MIFKE value per CSA of 4.54 +/- 0.7 N m cm-2 in M40 was greater (P < 0. 05-0.01) than that of 4.02 +/- 0.7 N m cm-2 recorded in M65. The maximal rate of force development of the knee extensors and flexors in M65 was lower (P < 0.01-0.001) and the heights in squat and counter-movement jumps as much as 27-29% lower (P < 0.001) than those recorded in M40. M65 showed lower (P < 0.001) concentric power values for both upper and lower extremity performances than those recorded for M40. Maximal power output was maximized at the 30-45% loads for the upper extremity and at the 60-70% loads for the lower extremity extensors in both age groups. Muscle activation of the antagonists was significantly higher (P < 0.01-0.001) during the isometric and dynamic knee extension actions in M65 than in M40. The present results support a general concept that parallel declines in muscle mass and maximal strength take place with increasing age, although loss of strength may vary in both lower and upper extremity muscles in relation to the type of action and that ageing may also lead to a decrease in voluntary neural drive to the muscles. Explosive strength and power seem to decrease with increasing age even more than maximal isometric strength in both actions but power was maximized at the 30-45% loads for the upper and at the 60-70% loads for the lower extremity action in both age groups. High antagonist muscle activity may limit the full movement efficiency depending on the type of muscle action, testing conditions and the velocity and/or the time duration of the action, especially in the elderly.
We concluded that a high-intensity resistance training program increases arterial stiffness and wave reflection in young healthy women. Our present interventional results are consistent with the previous cross-sectional studies in men in which high-intensity strength training is associated with arterial stiffening.
Decreased central arterial compliance is an emerging risk factor for cardiovascular disease. Resistance training is associated with reductions in the elastic properties of central arteries. Currently, it is not known whether this reduction is from one bout of resistance exercise or from an adaptation to multiple bouts of resistance training. Sixteen healthy sedentary or recreationally active adults (11 men and 5 women, age 27 +/- 1 yr) were studied under parallel experimental conditions on 2 separate days. The order of experiments was randomized between resistance exercise (9 resistance exercises at 75% of 1 repetition maximum) and sham control (seated rest in the exercise room). Baseline hemodynamic values were not different between the two experimental conditions. Carotid arterial compliance (via simultaneous B-mode ultrasound and applanation tonometry) decreased and beta-stiffness index increased (P < 0.01) immediately and 30 min after resistance exercise. Immediately after resistance exercise, carotid systolic blood pressure increased (P < 0.01), although no changes were observed in brachial systolic blood pressure at any time points. These measures returned to baseline values within 60 min after the completion of resistance exercise. No significant changes in these variables were observed during the sham control condition. These results indicate that one bout of resistance exercise acutely decreases central arterial compliance, but this effect is sustained for <60 min after the completion of resistance exercise.
Effects of 16-wk strength training on maximal strength and power performance of the arm and leg muscles and serum concentrations [testosterone (T), free testosterone (FT), and cortisol] were examined in 11 middle-aged (M46; 46 +/- 2 yr) and 11 older men (M64; 64 +/- 2 yr). During the 16-wk training, the relative increases in maximal strength and muscle power output of the arm and leg muscles were significant in both groups (P < 0.05-0.001), with no significant differences between the two groups. The absolute increases were higher (P < 0.01-0.05) in M46 than in M64 mainly during the last 8 wk of training. No significant changes were observed for serum T and FT concentrations. Analysis of covariance showed that, during the 16-wk training period, serum FT concentrations tended to decrease in M64 and increase in M46 (P < 0.05). However, significant correlations between the mean level of individual serum T and FT concentrations and the individual changes in maximal strength were observed in a combined group during the 16-wk training (r = 0.49 and 0.5, respectively; P < 0.05). These data indicate that a prolonged total strength-training program would lead to large gains in maximal strength and power load characteristics of the upper and lower extremity muscles, but the pattern of maximal and power development seemed to differ between the upper and lower extremities in both groups, possibly limited in magnitude because of neuromuscular and/or age-related endocrine impairments.
Alcohol abuse is frequently characterized by a specific pattern of intake in binge drinking episodes, inducing neuroinflammation and brain damage. Here, we characterized the temporal profile of neuroinflammation in rats exposed to intragastric binge ethanol administrations (3 times/day × 4 days) and tested the anti-inflammatory/neuroprotective properties of the satiety factor oleoylethanolamide (OEA). Pre-treatment with OEA (5 mg/kg, i.p.) previous each alcohol gavage blocked the expression of high mobility group box 1 (HMGB1) danger signal and the innate immunity Toll-like receptors 4 (TLR4) in frontal cortex, and inhibited the nuclear factor-kappa B (NF-kB) proinflammatory cascade induced by alcohol binge administration. OEA reduced the levels of interleukin-1beta (IL-1β), the monocyte chemoattractant protein-1 (MCP-1), and the enzymes cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in ethanol binged animals. Elevations in plasma tumor necrosis factor alpha (TNF-α) and IL-1β after ethanol were also inhibited by OEA. OEA also prevented ethanol-induced lipid peroxidation, caspase-8 and pro-apoptotic caspase-3 activation in frontal cortex. Additionally, OEA blocked the rise in blood corticosterone levels after ethanol with no alteration in blood ethanol levels and may affect ethanol-induced gut permeability for endotoxin. Finally, OEA, administered as a pre-treatment during the ethanol binge, exerted antidepressant-like effects during acute withdrawal. Altogether, results highlight a beneficial profile of OEA as a potent anti-inflammatory, antioxidant, neuroprotective and antidepressant-like compound to treat alcohol abuse.
Background:The acylethanolamides oleoylethanolamide and palmitoylethanolamide are endogenous lipid mediators with proposed neuroprotectant properties in central nervous system (CNS) pathologies. The precise mechanisms remain partly unknown, but growing evidence suggests an antiinflammatory/antioxidant profile.Methods:We tested whether oleoylethanolamide/palmitoylethanolamide (10mg/kg, i.p.) attenuate neuroinflammation and acute phase responses (hypothalamus-pituitary-adrenal (HPA) stress axis stress axis activation, thermoregulation, and anhedonia) induced by lipopolysaccharide (0.5mg/kg, i.p.) in rats.Results:Lipopolysaccharide increased mRNA levels of the proinflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interleukin-6, nuclear transcription factor-κB activity, and the expression of its inhibitory protein IκBα in cytoplasm, the inducible isoforms of nitric oxide synthase and cyclooxygenase-2, microsomal prostaglandin E2 synthase mRNA, and proinflammatory prostaglandin E2 content in frontal cortex 150 minutes after administration. As a result, the markers of nitrosative/oxidative stress nitrites (NO2 -) and malondialdehyde were increased. Pretreatment with oleoylethanolamide/ palmitoylethanolamide reduced plasma tumor necrosis factor-α levels after lipopolysaccharide, but only oleoylethanolamide significantly reduced brain tumor necrosis factor-α mRNA. Oleoylethanolamide and palmitoylethanolamide prevented lipopolysaccharide-induced nuclear transcription factor-κB (NF-κB)/IκBα upregulation in nuclear and cytosolic extracts, respectively, the expression of inducible isoforms of nitric oxide synthase, cyclooxygenase-2, and microsomal prostaglandin E2 synthase and the levels of prostaglandin E2. Additionally, both acylethanolamides reduced lipopolysaccharide-induced oxidative/nitrosative stress. Neither oleoylethanolamide nor palmitoylethanolamide modified plasma corticosterone levels after lipopolysaccharide, but both acylethanolamides reduced the expression of hypothalamic markers of thermoregulation interleukin-1β, cyclooxygenase-2, and prostaglandin E2, and potentiated the hypothermic response after lipopolysaccharide. Interestingly, only oleoylethanolamide disrupted lipopolysaccharide-induced anhedonia in a saccharine preference test.Conclusions:Results indicate that oleoylethanolamide and palmitoylethanolamide have antiinflammatory/neuroprotective properties and suggest a role for these acylethanolamides as modulators of CNS pathologies with a neuroinflammatory component.
Age-related reductions in basal limb blood flow and vascular conductance are associated with the metabolic syndrome, functional impairments, and osteoporosis. We tested the hypothesis that a strength training program would increase basal femoral blood flow in aging adults. Twenty-six sedentary but healthy middle-aged and older subjects were randomly assigned to either a whole body strength training intervention group (52 +/- 2 yr, 3 men, 10 women) who underwent three supervised resistance training sessions per week for 13 wk or a control group (53 +/- 2 yr, 4 men, 9 women) who participated in a supervised stretching program. At baseline, there were no significant differences in blood pressure, cardiac output, basal femoral blood flow (via Doppler ultrasound), vascular conductance, and vascular resistance between the two groups. The strength training group increased maximal strength in all the major muscle groups tested (P < 0.05). Whole body lean body mass increased (P < 0.05) with strength training, but leg fat-free mass did not. Basal femoral blood flow and vascular conductance increased by 55-60% after strength training (both P < 0.05). No such changes were observed in the control group. In both groups, there were no significant changes in brachial blood pressure, plasma endothelin-1 and angiotensin II concentrations, femoral artery wall thickness, cardiac output, and systemic vascular resistance. Our results indicate that short-term strength training increases basal femoral blood flow and vascular conductance in healthy middle-aged and older adults.
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