Post-prandial hyperlipidaemia results in systemic nitrosative stress and impaired cerebrovascular function in the aged

2017 ◽  
Vol 131 (23) ◽  
pp. 2807-2812 ◽  
Author(s):  
Christopher J. Marley ◽  
Danielle Hodson ◽  
Julien V. Brugniaux ◽  
Lewis Fall ◽  
Damian M. Bailey
Keyword(s):  
Free Radical ◽  
Nitrosative Stress ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Venous Blood ◽  
Cerebrovascular Reactivity ◽  
Resonance Spectroscopy ◽  
High Fat ◽  
Ascorbate Free Radical ◽  
Cerebrovascular Function ◽  
Fat Meal

Post-prandial hyperlipidaemia (PPH) acutely impairs systemic vascular endothelial function, potentially attributable to a free radical-mediated reduction in vascular nitric oxide (NO) bioavailability (oxidative–nitrosative stress). However, it remains to be determined whether this extends to the cerebrovasculature. To examine this, 38 (19 young (≤35 years) and 19 aged (≥60 years)) healthy males were recruited. Cerebrovascular function (middle cerebral artery velocity, MCAv) and cerebrovascular reactivity to hypercapnea (CVRCO2Hyper) and hypocapnea (CVRCO2Hypo) were determined via trans-cranial Doppler ultrasound and capnography. Venous blood samples were obtained for the assessment of triglycerides (photometry), glucose (photometry), insulin (radioimmunoassay), ascorbate free radical (A•−, electron paramagnetic resonance spectroscopy) and nitrite (NO2–, ozone-based chemiluminescence) in the fasted state prior to and 4 h following consumption of a standardized high-fat meal (1362 kcal; 130 g of fat). Circulating triglycerides, glucose and insulin increased in both groups following the high-fat meal (P<0.05), with triglycerides increasing by 1.37 ± 1.09 mmol/l in the young and 1.54 ± 1.00 mmol/l in the aged (P<0.05). This resulted in an increased systemic formation of free radicals in the young (P<0.05) but not the aged (P>0.05) and corresponding reduction in NO2– in both groups (P<0.05). While the meal had no effect on MCAv in either age group, CVRCO2Hyper was selectively impaired in the aged (P<0.05). These findings indicate that PPH causes acute cerebrovascular dysfunction in the aged subsequent to systemic nitrosative stress.

scholarly journals The Contribution of Arterial Blood Gases in Cerebral Blood Flow Regulation and Fuel Utilization in Man at High Altitude

2015 ◽  
Vol 35 (5) ◽  
pp. 873-881 ◽  
Author(s):  
Christopher K Willie ◽  
David B MacLeod ◽  
Kurt J Smith ◽  
Nia C Lewis ◽  
Glen E Foster ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
High Altitude ◽  
Cerebral Metabolism ◽  
Venous Blood ◽  
Blood Gases ◽  
Cerebrovascular Reactivity ◽  
Arterial Blood Gases ◽  
Arterial Blood ◽  
Cerebrovascular Function

The effects of partial acclimatization to high altitude (HA; 5,050 m) on cerebral metabolism and cerebrovascular function have not been characterized. We hypothesized (1) increased cerebrovascular reactivity (CVR) at HA; and (2) that CO2 would affect cerebral metabolism more than hypoxia. PaO2 and PaCO2 were manipulated at sea level (SL) to simulate HA exposure, and at HA, SL blood gases were simulated; CVR was assessed at both altitudes. Arterial–jugular venous differences were measured to calculate cerebral metabolic rates and cerebral blood flow (CBF). We observed that (1) partial acclimatization yields a steeper CO2-H+ relation in both arterial and jugular venous blood; yet (2) CVR did not change, despite (3) mean arterial pressure (MAP)-CO2 reactivity being doubled at HA, thus indicating effective cerebral autoregulation. (4) At SL hypoxia increased CBF, and restoration of oxygen at HA reduced CBF, but neither had any effect on cerebral metabolism. Acclimatization resets the cerebrovasculature to chronic hypocapnia.

Antioxidant Activity of Selected Thyme (Thymus L.) Species and Study of the Equivalence of Different Measuring Methodologies

2015 ◽  
Vol 98 (4) ◽  
pp. 876-882 ◽  
Author(s):  
Marta Orłowska ◽  
Teresa Kowalska ◽  
Mieczysław Sajewicz ◽  
Katarzyna Pytlakowska ◽  
Mariola Bartoszek ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Radical Scavenging ◽  
Cost Effective ◽  
Resonance Spectroscopy ◽  
Dpph Radical ◽  
Dot Blot ◽  
Phenolic Fraction ◽  
Measuring Techniques

Abstract This study presents the results of comparative evaluation of the antioxidant activity of the phenolic fraction exhaustively extracted with aqueous methanol from 18 different thyme (Thymus L.) specimens and species. This evaluation is made with use of the same free radical source (DPPH• radical), three different free radical scavenging models (gallic acid, ascorbic acid, and Trolox), and three different measuring techniques (the dot blot test, UV-Vis spectrophotometry, and electron paramagnetic resonance spectroscopy, EPR). A comparison of the equivalence of these three different measuring techniques (performed with use of hierarchical clustering with Euclidean distance as a similarity measure and Ward's linkage) is particularly important in view of the fact that different laboratories use different antioxidant activity measuring techniques, which makes any interlaboratory comparison hardly possible. The results obtained confirm a semiquantitative equivalence among the three compared methodologies, and a proposal is made of a simple and cost-effective dot blot test that uses the DPPH• radical and provides differentiation of antioxidant activity of herbal matter comparable with the results of the UV-Vis spectrophotometry and EPR.

scholarly journals Is the effect of prior exercise on postprandial lipaemia the same for a moderate-fat meal as it is for a high-fat meal?

2010 ◽  
Vol 105 (4) ◽  
pp. 506-516 ◽  
Author(s):  
Nicholas M. Hurren ◽  
Frank F. Eves ◽  
Andrew K. Blannin
Keyword(s):  
Test Meal ◽  
Venous Blood ◽  
Exercise Bout ◽  
Moderate Intensity ◽  
High Fat ◽  
Moderate Intensity Exercise ◽  
Postprandial Lipaemia ◽  
Fasted State ◽  
Prior Exercise ◽  
Fat Meal

Moderate-intensity exercise can lower the TAG response to a high-fat meal; however, the British diet is moderate in fat, and no study to date has compared the effect of such exercise on responses to high-fat and moderate-fat meals. The present work investigated the effect of brisk walking performed 13 h before intake of both high-fat and moderate-fat meals on postprandial plasma TAG concentrations. Eight inactive, overweight men completed four separate 2 d trials, i.e. rest (Con) or a 90-min treadmill walk (Ex) on the evening of day 1, followed by the ingestion of a moderate-fat (Mod) or high-fat (High) meal on the morning of day 2. High-fat meals contained 66 % of total energy as fat, while the percentage was 35 % for moderate-fat meals; both the meals were, however, isoenergetic. On day 2, venous blood was sampled in the fasted state, 30 and 60 min after ingesting the test meal and then hourly until 6 h post-meal. Exercise reduced plasma TAG concentrations significantly (P < 0·001), with no exercise × meal interaction (P = 0·459). Walking reduced the total TAG response to a high-fat meal by 29 % (relative to High Con); the same bout of exercise performed before ingesting a moderate-fat meal lowered total TAG by 26 % (compared with Mod Con). The ability of a single moderate-intensity aerobic exercise bout to lower postprandial TAG concentrations is just as great, in percentage terms, when the test meal ingested is of a moderate rather than a high fat content.

scholarly journals Elevated Levels of Apolipoprotein CIII Increase the Risk of Postprandial Hypertriglyceridemia

2021 ◽  
Vol 12 ◽  
Author(s):  
Yunpeng Guan ◽  
Xiaoyu Hou ◽  
Peipei Tian ◽  
Luping Ren ◽  
Yong Tang ◽  
...  
Keyword(s):  
Waist Circumference ◽  
Venous Blood ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Model Assessment ◽  
High Fat ◽  
Clinical Trial Registry ◽  
Postprandial Hypertriglyceridemia ◽  
Group 2 ◽  
Fat Meal

BackgroundTo investigate possible mechanisms of postprandial hypertriglyceridemia (PPT), we analyzed serum lipid and apolipoprotein (Apo) AI, B, CII and CIII levels before and after a high-fat meal.MethodsThe study has been registered with the China Clinical Trial Registry (registration number:ChiCTR1800019514; URL: http://www.chictr.org.cn/index.aspx). We recruited 143 volunteers with normal fasting triglyceride (TG) levels. All subjects consumed a high-fat test meal. Venous blood samples were obtained during fasting and at 2, 4, and 6 hours after the high-fat meal. PPT was defined as TG ≥2.5 mmol/L any time after the meal. Subjects were divided into two groups according to the high-fat meal test results: postprandial normal triglyceride (PNT) and PPT. We compared the fasting and postprandial lipid and ApoAI, ApoB, ApoCII and ApoCIII levels between the two groups.ResultsSignificant differences were found between the groups in fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), TG, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), TG-rich lipoprotein remnants (TRLRs), ApoB, ApoCIII, ApoAI/ApoB and ApoCII/ApoCIII. The insulin, HOMA-IR, TG, TC, LDL-C, non-HDL-C, TRLRs, ApoB, ApoCIII and ApoCII/ApoCIII values were higher in the PPT group, while the ApoAI/ApoB ratio was higher in the PNT group. The postprandial TG level peaked in the PNT group 2 hours after the meal but was significantly higher in the PPT group and peaked at 4 hours. TRLRs gradually increased within 6 hours after the high-fat meal in both groups. The area under the curve (AUC) of TG and TRLRs and the AUC increment were higher in the PPT group (P &lt; 0.001). ApoCIII peaked in the PNT group 2 hours after the meal and gradually decreased. ApoCIII gradually increased in the PPT group within 6 hours after the meal, exhibiting a greater AUC increment (P &lt; 0.001). Fasting ApoCIII was positively correlated with age, systolic and diastolic blood pressure, body mass index (BMI), waist circumference, TC, TG, LDL-C, non-HDL-C, TRLRs, and ApoB (P&lt;0.05). ApoCIII was an independent risk factor of PPT after adjustment for BMI, waist circumference, TC, LDL-C, and ApoB (P &lt; 0.001, OR=1.188).ConclusionsElevated ApoCIII levels may cause PPT.

scholarly journals The Impact of High-Fat Diet on Mitochondrial Function, Free Radical Production, and Nitrosative Stress in the Salivary Glands of Wistar Rats

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Anna Zalewska ◽  
Dominika Ziembicka ◽  
Małgorzata Żendzian-Piotrowska ◽  
Mateusz Maciejczyk
Keyword(s):  
Oxidative Stress ◽  
Free Radical ◽  
High Fat Diet ◽  
Wistar Rats ◽  
Nitrosative Stress ◽  
Ros Production ◽  
Parotid Glands ◽  
High Fat ◽  
Free Radical Production ◽  
Radical Production

Oxidative stress plays a crucial role in the salivary gland dysfunction in insulin resistance; however, the cause of increased free radical formation in these conditions is still unknown. Therefore, the aim of the study was to investigate the effect of high-fat diet (HFD) on the mitochondrial respiratory system, prooxidant enzymes, ROS production, and nitrosative/oxidative stress in the submandibular and parotid glands of rats. The experiment was performed on male Wistar rats divided into two groups (n=10): control and HFD. The 8-week feeding of HFD affects glucose metabolism observed as significant increase in plasma glucose and insulin as well as HOMA-IR as compared to the control rats. The activity of mitochondrial Complex I and Complex II+III was significantly decreased in the parotid and submandibular glands of HFD rats. Mitochondrial cytochrome c oxidase (COX) activity and the hydrogen peroxide level were significantly increased in the parotid and submandibular glands of the HFD group as compared to those of the controls. HFD rats also showed significantly lower reduced glutathione (GSH) and reduced : oxidized glutathione (GSH : GSSG) ratio, as well as a higher GSSG level in the parotid glands of HFD rats. The activity of NADPH oxidase, xanthine oxidase, and levels of oxidative/nitrosative stress (malonaldehyde, nitric oxide, nitrotyrosine, and peroxynitrite) and inflammation/apoptosis (interleukin-1βand caspase-3) biomarkers were statistically elevated in the HFD group in comparison to the controls. HFD impairs mitochondrial function in both types of salivary glands by enhancing ROS production, as well as stimulating inflammation and apoptosis. However, free radical production, protein nitration, and lipid peroxidation were more pronounced in the parotid glands of HFD rats.

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