Evidence against redox regulation of energy homoeostasis in humans at high altitude

2004 ◽  
Vol 107 (6) ◽  
pp. 589-600 ◽  
Author(s):  
Damian M. BAILEY ◽  
Philip N. AINSLIE ◽  
Simon K. JACKSON ◽  
Russell S. RICHARDSON ◽  
Mohammed GHATEI
Keyword(s):  
Placebo Group ◽  
Free Radicals ◽  
High Altitude ◽  
Sea Level ◽  
Redox Regulation ◽  
Caloric Intake ◽  
Eating Behaviour ◽  
Double Blind ◽  
Ascorbate Free Radical ◽  
Markers Of Inflammation

The present study examined if free radicals and associated inflammatory sequelae influenced metabolic biomarkers involved in the neuro-endocrinological regulation of energy homoeostasis at high altitude. Sixteen mountaineers (11 males/five females) were matched for physical fitness and caloric intake and assigned in a double-blind manner to either antioxidant (n=8) or placebo (n=8) supplementation, which was enforced for 7 days at sea level and during an 11-day ascent to 4780 m. Enteral prophylaxis incorporated a daily bolus dose of 1 g of L-ascorbate, 400 international units of D,L-α-tocopherol acetate and 600 mg of α-lipoic acid. EPR (electron paramagnetic resonance) spectroscopic detection of PBN (α-phenyl-tert-butylnitrone) adducts confirmed an increase in the venous concentration of carbon-centred radicals at high altitude in the placebo group, whereas a decrease was observed in the antioxidant group (P<0.05 compared with that at sea level). EPR detection of DMSO/A˙− (DMSO-supplemented ascorbate free radical) demonstrated that the increase in carbon-centred radicals at high altitude was associated with a decrease in ascorbate (r2=0.63; P<0.05). Ascent to high altitude (pooled placebo+antioxidant groups) also increased the expression of pro-inflammatory cytokines (P<0.05 compared with that at sea level) and biomarkers of skeletal tissue damage (P<0.05). Despite a general decrease in leptin, insulin and glucose at high altitude (pooled placebo+antioxidant groups; P<0.05 compared with that at sea level), persistent anorexia resulted in a selective loss of body fat (P<0.05). In conclusion, antioxidant prophylaxis decreased the concentration of carbon-centred radicals at high altitude (P<0.05 compared with the placebo group), but did not influence markers of inflammation, appetite-related peptides, ad libitum nutrient intake or body composition. Thus free radicals do not appear to be involved in the inflammatory response and subsequent control of eating behaviour at high altitude.

Improvement in lung diffusion by endothelin A receptor blockade at high altitude

2012 ◽  
Vol 112 (1) ◽  
pp. 20-25 ◽  
Author(s):  
Claire de Bisschop ◽  
Jean-Benoit Martinot ◽  
Gil Leurquin-Sterk ◽  
Vitalie Faoro ◽  
Hervé Guénard ◽  
...  
Keyword(s):  
High Altitude ◽  
Sea Level ◽  
Exercise Capacity ◽  
Barometric Pressure ◽  
Membrane Component ◽  
Alveolar Volume ◽  
Double Blind ◽  
Lung Diffusion ◽  
Endothelin A Receptor ◽  
Endothelin A

Lung diffusing capacity has been reported variably in high-altitude newcomers and may be in relation to different pulmonary vascular resistance (PVR). Twenty-two healthy volunteers were investigated at sea level and at 5,050 m before and after random double-blind intake of the endothelin A receptor blocker sitaxsentan (100 mg/day) vs. a placebo during 1 wk. PVR was estimated by Doppler echocardiography, and exercise capacity by maximal oxygen uptake (V̇o2 max). The diffusing capacities for nitric oxide (DLNO) and carbon monoxide (DLCO) were measured using a single-breath method before and 30 min after maximal exercise. The membrane component of DLCO (Dm) and capillary volume (Vc) was calculated with corrections for hemoglobin, alveolar volume, and barometric pressure. Altitude exposure was associated with unchanged DLCO, DLNO, and Dm but a slight decrease in Vc. Exercise at altitude decreased DLNO and Dm. Sitaxsentan intake improved V̇o2 max together with an increase in resting and postexercise DLNO and Dm. Sitaxsentan-induced decrease in PVR was inversely correlated to DLNO. Both DLCO and DLNO were correlated to V̇o2 max at sea level ( r = 0.41–0.42, P < 0.1) and more so at altitude ( r = 0.56–0.59, P < 0.05). Pharmacological pulmonary vasodilation improves the membrane component of lung diffusion in high-altitude newcomers, which may contribute to exercise capacity.

Body composition at sea level and high altitudes

1961 ◽  
Vol 16 (4) ◽  
pp. 589-592 ◽  
Author(s):  
E. PicÓn-Reátegui ◽  
Rodolfo Lozano ◽  
José Valdivieso
Keyword(s):  
Physical Activity ◽  
Body Composition ◽  
Body Weight ◽  
High Altitude ◽  
Sea Level ◽  
Total Body Water ◽  
Physical Inactivity ◽  
Caloric Intake ◽  
Extracellular Fluid ◽  
Total Body

Simultaneous determinations of total body water and extracellular fluid, using the antipyrine and sucrose infusion methods, have been carried out in 28 adult male residents at sea level and in 28 residents at an altitude of 14,900 ft. Body composition was calculated from these data. The various body spaces, expressed in percentage of body weight, were similar in the two groups, with the exception of the extracellular fluid which was greater in those in the high altitude group ( P < 0.01). Neither racial characteristics nor altitude appear to be factors generally affecting body composition. In individuals having adequate caloric intake body composition seems to be influenced principally by physical activity. In fact, physical inactivity appeared to produce a loss of active tissue and its replacement by fat. Submitted on November 2, 1960

scholarly journals Effect of Clarithromycin in Inflammatory Markers of Patients with Ventilator-Associated Pneumonia and Sepsis Caused by Gram-Negative Bacteria: Results from a Randomized Clinical Study

2012 ◽  
Vol 56 (7) ◽  
pp. 3819-3825 ◽  
Author(s):  
Aikaterini Spyridaki ◽  
Maria Raftogiannis ◽  
Anastasia Antonopoulou ◽  
Thomas Tsaganos ◽  
Christina Routsi ◽  
...  
Keyword(s):  
Septic Shock ◽  
Placebo Group ◽  
Ventilator Associated Pneumonia ◽  
Double Blind ◽  
Soluble Cd40 Ligand ◽  
Necrosis Factor Alpha ◽  
Risk Of Death ◽  
Markers Of Inflammation ◽  
Randomized Clinical Study ◽  
Tnf Α

ABSTRACTOne recent, double-blind, randomized clinical trial with 200 patients showed that clarithromycin administered intravenously for 3 days in patients with ventilator-associated pneumonia (VAP) accelerated the resolution of pneumonia and decreased the risk of death from septic shock and multiple organ dysfunctions (MODS). The present study focused on the effect of clarithromycin on markers of inflammation in these patients. Blood was drawn immediately before the administration of the allocated treatment and on six consecutive days after the start of treatment. The concentrations of circulating markers were measured. Monocytes and neutrophils were isolated for immunophenotyping analysis and for cytokine stimulation. The ratio of serum interleukin-10 (IL-10) to serum tumor necrosis factor alpha (TNF-α) was decreased in the clarithromycin group compared with the results in the placebo group. Apoptosis of monocytes was significantly increased on day 4 in the clarithromycin group compared with the rate of apoptosis in the placebo group. On the same day, the expression of CD86 was increased and the ratio of soluble CD40 ligand (sCD40L) to CD86 in serum was unchanged. The release of TNF-α, IL-6, and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) by circulating monocytes after stimulation was greater in the clarithromycin group than in the placebo group. The expression of TREM-1 on monocytes was also increased in the former group. These effects were pronounced in patients with septic shock and MODS. These results suggest that the administration of clarithromycin restored the balance between proinflammatory versus anti-inflammatory mediators in patients with sepsis; this was accompanied by more efficient antigen presentation and increased apoptosis. These effects render new perspectives for the immunotherapy of sepsis.

Hypoxia-induced oxidative stress in high altitude population: impact of coenzyme Q10 supplementation

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ayman R. Biuomy ◽  
Fatma S. H. Oraby ◽  
Eman A. Khalifa ◽  
Hanaa A. El-Sherif ◽  
Jihan Hussein ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Placebo Group ◽  
Vitamin E ◽  
High Altitude ◽  
Sea Level ◽  
Coenzyme Q10 ◽  
High Performance ◽  
Base Line ◽  
Antioxidant Parameters ◽  
Coq10 Supplementation

Abstract Objective The aim of this study was to investigate the effect of coenzyme Q10 (CoQ10) supplementation on oxidative stress engendered from hypoxia in population live at high altitude. Methods This is an intervention study in which 50 females of volunteers population-36 of them who live at high altitude compared with the placebo group (14 from the total population that live at sea level). Blood samples were collected in -anticoagulant tubes from control and high altitude before and after CoQ10 supplementation (150 mg/day for 2, 4 and 8 weeks). Plasma was separated and used for the determination of malondialdehyde (MDA), nitric oxide (NOx), total antioxidant capacity (TAC), paraoxonase (PON1) by spectrophotometer, CoQ10 and vitamin E by high performance liquid chromatography (HPLC). Results Our results appeared that TAC, PON1, vitamin E and CoQ10 concentrations were significantly decreased in population at high altitude at base line compared to placebo group population at sea level. Whereas, administration of CoQ10 attenuated all measured parameters especially after eight weeks of administration. Conclusion We concluded that coenzyme Q10 supplement at a dose of 150 mg/day has a powerful effect in oxidative stress parameters and increased antioxidant parameters included vitamin E in population with hypoxia after 4 and 8 weeks. So that supplementation positively affects oxidative stress and is recommended CoQ10 supplementation in population who live at high altitude.

The Effect of Warfarin Sodium on the Duration of Platelet Aggregation

1967 ◽  
Vol 18 (03/04) ◽  
pp. 766-778 ◽  
Author(s):  
H. J Knieriem ◽  
A. B Chandler
Keyword(s):  
Platelet Count ◽  
Placebo Group ◽  
Platelet Aggregation ◽  
Prothrombin Time ◽  
Platelet Rich Plasma ◽  
Healthy Adults ◽  
Double Blind Study ◽  
Double Blind ◽  
Warfarin Sodium

SummaryThe effect of the administration of warfarin sodium (Coumadin®) on the duration of platelet aggregation in vitro was studied. Coumadin was given for 4 consecutive days to 10 healthy adults who were followed over a period of 9 days. The duration of adenosine diphosphate-induced platelet aggregation in platelet-rich plasma, the prothrombin time, and the platelet count of platelet-rich plasma were measured. Four other healthy adults received placebos and participated in a double-blind study with those receiving Coumadin.Although administration of Coumadin caused a prolongation of the prothrombin time to 2 or 21/2 times the normal value, a decrease in the duration of platelet aggregation was not observed. In most individuals who received Coumadin an increase in the duration of platelet aggregation occurred. The effect of Coumadin on platelet aggregation was not consistently related to the prothrombin time or to the platelet count. In the placebo group there was a distinct relation between the duration of platelet aggregation and the platelet count in platelet-rich plasma.The mean increase in the duration of platelet aggregation when compared to the control value before medication with Coumadin was 37.7%. In the placebo group there was a mean increase of 8.4%. The difference between the two groups is significant (p <0.001). Increased duration of platelet aggregation also occurred in two individuals who received Coumadin over a period of 10 and 16 days respectively.

Double-blind, randomized controlled trial of tranexamic acid in minor lumbar spine surgery: no effect on operative time, intraoperative blood loss, or complications

2019 ◽  
Vol 31 (2) ◽  
pp. 194-200 ◽  
Author(s):  
Signe Elmose ◽  
Mikkel Ø. Andersen ◽  
Else Bay Andresen ◽  
Leah Yacat Carreon
Keyword(s):  
Placebo Group ◽  
Lumbar Spine ◽  
Blood Loss ◽  
Tranexamic Acid ◽  
Spine Surgery ◽  
Operative Time ◽  
Decompressive Surgery ◽  
Lumbar Spine Surgery ◽  
Intraoperative Blood Loss ◽  
Double Blind

OBJECTIVEThe purpose of this study was to investigate the effect of tranexamic acid (TXA) compared to placebo in low-risk adult patients undergoing elective minor lumbar spine surgery—specifically with respect to operative time, estimated blood loss, and complications. Studies have shown that TXA reduces blood loss during major spine surgery. There have been no previous studies on the effect of TXA in minor lumbar spine surgery in which these variables have been evaluated.METHODSThe authors enrolled patients with ASA grades 1 to 2 scheduled to undergo lumbar decompressive surgery at Middelfart Hospital into a double-blind, randomized, placebo-controlled, parallel-group study. Patients with thromboembolic disease, coagulopathy, hypersensitivity to TXA, or a history of convulsion were excluded. Patients were randomly assigned, in blocks of 10, to one of 2 groups, TXA or placebo. Anticoagulation therapy was discontinued 2–7 days preoperatively. Prior to the incision, patients received either a bolus of TXA (10 mg/kg) or an equivalent volume of saline solution (placebo). Independent t-tests were used to compare differences between the 2 groups, with statistical significance set at p < 0.05.RESULTSOf the 250 patients enrolled, 17 patients were excluded, leaving 233 cases for analysis (117 in the TXA group and 116 in the placebo group). The demographics of the 2 groups were similar, except for a higher proportion of women in the TXA group (TXA 50% vs placebo 32%, p = 0.017). There was no significant between-groups difference in operative time (49.53 ± 18.26 vs 54.74 ± 24.49 minutes for TXA and placebo, respectively; p = 0.108) or intraoperative blood loss (55.87 ± 48.48 vs 69.14 ± 83.47 ml for TXA and placebo, respectively; p = 0.702). Postoperative blood loss measured from drain output was 62% significantly lower in the TXA group (13.03 ± 21.82 ml) than in the placebo group (34.61 ± 44.38 ml) (p < 0.001). There was no significant difference in number of dural lesions or postoperative spinal epidural hematomas, and there were no thromboembolic events.CONCLUSIONSTranexamic acid did not have a statistically significant effect on operative time, intraoperative blood loss, or complications. This study gives no evidence to support the routine use of TXA during minor lumbar decompressive surgery.Clinical trial registration no.: NCT03714360 (clinicaltrials.gov)

Effects of Consumption of Probiotic Powder Containing Lactobacillus Plantarum Dad-13 on Fecal Bacterial Population in School-Age Children in Indonesia

2019 ◽  
Vol 14 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Banin Maghfirotin Marta ◽  
Utami Tyas ◽  
Cahyanto Muhammad Nur ◽  
Widada Jaka ◽  
Rahayu Endang Sutriswati
Keyword(s):  
Placebo Group ◽  
Gut Microbiota ◽  
Lactobacillus Plantarum ◽  
Coliform Bacteria ◽  
School Age Children ◽  
Controlled Study ◽  
School Age ◽  
Double Blind ◽  
Probiotic Group ◽  
E Coli

Consumption of probiotics is known to influence the gut microbiota. The aim of this study was to assess the effect of probiotic powder containing Lactobacillus plantarum Dad-13 on bacterial composition in the gut by examining fecal samples of school-age children in Yogyakarta, Indonesia. This is a randomized, double-blind, placebo-controlled study. A total of 40 healthy subjects were recruited for this study and were divided into two groups: placebo group and probiotic group. The placebo group consumed skim milk and the probiotic group consumed probiotic powder containing L. plantarum Dad-13 (2 × 109 CFU/g) for 65 days. The results showed that placebo intake had no significant effect on gut microbiota; however, probiotic caused a significant increase in L. plantarum and Lactobacillus population, while decreasing the population of E. coli and non-E. coli coliform bacteria by 55% and 75%, respectively and Bifidobacteria count did not change significantly. The study concluded that consumption of probiotic powder L. plantarum Dad-13 could increase propionic acid thereby decreasing the gut pH which has an effect on the microbial population.

scholarly journals The Effect of Protein Supplementation versus Carbohydrate Supplementation on Muscle Damage Markers and Soreness Following a 15-km Road Race: A Double-Blind Randomized Controlled Trial

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 858
Author(s):  
Dominique S. M. ten Haaf ◽  
Martin A. Flipsen ◽  
Astrid M. H. Horstman ◽  
Hans Timmerman ◽  
Monique A. H. Steegers ◽  
...  
Keyword(s):  
Placebo Group ◽  
Protein Intake ◽  
Muscle Soreness ◽  
Controlled Trial ◽  
Protein Supplementation ◽  
Group Differences ◽  
Double Blind ◽  
Carbohydrate Supplementation ◽  
Protein Group ◽  
Road Race

We assessed whether a protein supplementation protocol could attenuate running-induced muscle soreness and other muscle damage markers compared to iso-caloric placebo supplementation. A double-blind randomized controlled trial was performed among 323 recreational runners (age 44 ± 11 years, 56% men) participating in a 15-km road race. Participants received milk protein or carbohydrate supplementation, for three consecutive days post-race. Habitual protein intake was assessed using 24 h recalls. Race characteristics were determined and muscle soreness was assessed with the Brief Pain Inventory at baseline and 1–3 days post-race. In a subgroup (n = 149) muscle soreness was measured with a strain gauge algometer and creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations were measured. At baseline, no group-differences were observed for habitual protein intake (protein group: 79.9 ± 26.5 g/d versus placebo group: 82.0 ± 26.8 g/d, p = 0.49) and muscle soreness (protein: 0.45 ± 1.08 versus placebo: 0.44 ± 1.14, p = 0.96). Subjects completed the race with a running speed of 12 ± 2 km/h. With the Intention-to-Treat analysis no between-group differences were observed in reported muscle soreness. With the per-protocol analysis, however, the protein group reported higher muscle soreness 24 h post-race compared to the placebo group (2.96 ± 2.27 versus 2.46 ± 2.38, p = 0.039) and a lower pressure muscle pain threshold in the protein group compared to the placebo group (71.8 ± 30.0 N versus 83.9 ± 27.9 N, p = 0.019). No differences were found in concentrations of CK and LDH post-race between groups. Post-exercise protein supplementation is not more preferable than carbohydrate supplementation to reduce muscle soreness or other damage markers in recreational athletes with mostly a sufficient baseline protein intake running a 15-km road race.

scholarly journals Effects of Fermented Milk Containing Lacticaseibacillus paracasei Strain Shirota on Constipation in Patients with Depression: A Randomized, Double-Blind, Placebo-Controlled Trial

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2238
Author(s):  
Xiaomei Zhang ◽  
Shanbin Chen ◽  
Ming Zhang ◽  
Fazheng Ren ◽  
Yimei Ren ◽  
...  
Keyword(s):  
Mental Illness ◽  
Placebo Group ◽  
Rating Scale ◽  
Controlled Trial ◽  
Fermented Milk ◽  
Daily Consumption ◽  
Double Blind ◽  
Tnf Α ◽  
Significant Difference ◽  
Factor Α

Probiotics have been shown to benefit patients with constipation and depression, but whether they specifically alleviate constipation in patients with depression remains unclear. The aim of this study was to investigate the effect of Lacticaseibacillus paracasei strain Shirota (LcS), formerly Lactobacillus casei strain Shirota, on constipation in patients with depression with specific etiology and gut microbiota and on depressive regimens. Eighty-two patients with constipation were recruited. The subjects consumed 100 mL of a LcS beverage (108 CFU/mL) or placebo every day for 9 weeks. After ingesting beverages for this period, we observed no significant differences in the total patient constipation-symptom (PAC-SYM) scores in the LcS group when compared with the placebo group. However, symptoms/scores in item 7 (rectal tearing or bleeding after a bowel movement) and items 8–12 (stool symptom subscale) were more alleviated in the LcS group than in the placebo group. The Beck Depression Index (BDI) and Hamilton Depression Rating Scale (HAMD) scores were all significantly decreased, and the degree of depression was significantly improved in both the placebo and LcS groups (p < 0.05), but there was no significant difference between the groups. The LcS intervention increased the beneficial Adlercreutzia, Megasphaera and Veillonella levels and decreased the bacterial levels related to mental illness, such as Rikenellaceae_RC9_gut_group, Sutterella and Oscillibacter. Additionally, the interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) levels were significantly decreased in both the placebo and LcS groups (p < 0.05). In particular, the IL-6 levels were significantly lower in the LcS group than the placebo group after the ingestion period (p < 0.05). In conclusion, the daily consumption of LcS for 9 weeks appeared to relieve constipation and improve the potentially depressive symptoms in patients with depression and significantly decrease the IL-6 levels. In addition, the LcS supplementation also appeared to regulate the intestinal microbiota related to mental illness.

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