scholarly journals Prevention of in Vitro Lipolysis by Tetrahydrolipstatin

2000 ◽  
Vol 46 (7) ◽  
pp. 950-954 ◽  
Author(s):  
Michael Krebs ◽  
Harald Stingl ◽  
Peter Nowotny ◽  
Daniel Weghuber ◽  
Martin Bischof ◽  
...  
Keyword(s):  
Room Temperature ◽  
Storage Temperature ◽  
Lipolytic Activity ◽  
Accurate Determination ◽  
Plasma Concentrations ◽  
Metabolic Effects ◽  
In Vitro Lipolysis ◽  
Plasma Ffa ◽  
Plasma Ffas

Abstract Background: Metabolic effects of free fatty acids (FFAs) frequently are tested using combined infusion of triglycerides and heparin, which stimulates lipolysis in vivo. Ongoing in vitro lipolysis, however, probably produces falsely high plasma FFA concentrations under these conditions. Therefore, this study aims to assess the efficacy of tetrahydrolipstatin (THL) in inhibiting plasma lipolytic activity and to improve plasma FFA determination. Methods: Plasma concentrations of FFAs and glycerol were measured in five healthy subjects in the presence and absence of THL. Blood was drawn at baseline, during infusion of a triglyceride emulsion (1.5 mL/min), and during infusion of triglycerides plus heparin (0.2 IU · kg−1 · min−1). In addition, the effects of storage temperature of the samples were analyzed. Results: In samples frozen immediately after collection, plasma FFAs were 28% lower in the presence of THL than in its absence (P = 0.008). When THL-free plasma was incubated for 3 h on ice or at room temperature, plasma FFAs were 22% (P = 0.02) and 91% (P = 0.0004) higher, respectively, than in samples frozen immediately. The addition of THL blunted temperature-dependent in vitro lipolysis by 88% (P <0.01) and 89% (P <0.001) after incubation on ice and at room temperature, respectively. Changes in plasma glycerol concentrations exhibited similar behavior. Conclusions: THL, which is safe and easy to handle, is a potent inhibitor of in vitro lipolysis and could, therefore, be added to blood samples drawn during triglyceride/heparin infusions to allow more accurate determination of plasma FFA concentrations.

scholarly journals Impact of Anticoagulation and Sample Processing on the Quantification of Human Blood-Derived microRNA Signatures

Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1915 ◽  
Author(s):  
Marion Mussbacher ◽  
Teresa L. Krammer ◽  
Stefan Heber ◽  
Waltraud C. Schrottmaier ◽  
Stephan Zeibig ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Room Temperature ◽  
Ethylenediaminetetraacetic Acid ◽  
Plasma Concentrations ◽  
Circulating Microrna ◽  
Blood Samples ◽  
Edta Plasma ◽  
Thrombotic Diseases ◽  
And Storage

Blood-derived microRNA signatures have emerged as powerful biomarkers for predicting and diagnosing cardiovascular disease, cancer, and metabolic disorders. Platelets and platelet-derived microvesicles are a major source of microRNAs. We have previously shown that the inappropriate anticoagulation and storage of blood samples causes substantial platelet activation that is associated with the release of platelet-stored molecules into the plasma. However, it is currently unclear if circulating microRNA levels are affected by artificial platelet activation due to suboptimal plasma preparation. To address this issue, we used a standardized RT-qPCR test for 12 microRNAs (thrombomiR®, TAmiRNA GmbH, Vienna, Austria) that have been associated with cardiovascular and thrombotic diseases and were detected in platelets and/other hematopoietic cells. Blood was prevented from coagulating with citrate–theophylline–adenosine–dipyridamole (CTAD), sodium citrate, or ethylenediaminetetraacetic acid (EDTA) and stored for different time periods either at room temperature or at 4 °C prior to plasma preparation and the subsequent quantification of microRNAs. We found that five microRNAs (miR-191-5p, miR-320a, miR-21-5p, miR-23a-3p, and miR-451a) were significantly increased in the EDTA plasma. Moreover, we observed a time-dependent increase in plasma microRNAs that was most pronounced in the EDTA blood stored at room temperature for 24 h. Furthermore, significant correlations between microRNA levels and plasma concentrations of platelet-stored molecules pointed towards in vitro platelet activation. Therefore, we strongly recommend to (i) use CTAD as an anticoagulant, (ii) process blood samples as quickly as possible, and (iii) store blood samples at 4 °C whenever immediate plasma preparation is not feasible to generate reliable data on blood-derived microRNA signatures.

Stability of plasma lactate in vitro in the presence of antiglycolytic agents

1994 ◽  
Vol 40 (7) ◽  
pp. 1327-1330 ◽  
Author(s):  
R Astles ◽  
C P Williams ◽  
F Sedor
Keyword(s):  
Sodium Fluoride ◽  
Room Temperature ◽  
Storage Temperature ◽  
Plasma Lactate ◽  
Potassium Oxalate ◽  
The Mean ◽  
Definition Of ◽  
Preanalytical Conditions

Abstract The use of plasma lactate to assess metabolic or circulatory impairment requires definition of critical preanalytical and analytical parameters. Stability has been documented for only 15 min after acquisition when samples were collected with fluoride and transported on ice. We examined time elapsed before analysis, storage temperature, and the antiglycolytic agent used to define preanalytical conditions. Plasma lactate was measured with a Kodak Ektachem 700XR analyzer. In controlled studies on volunteers, storage on ice slowed but did not eliminate the production of lactate; for samples collected with sodium fluoride (F) and potassium oxalate (OX), lactate increased by 0.2 mmol/L after 1 h, then changed little regardless of the storage temperature. For patients' samples collected in F/OX, the mean increase was only 0.15 mmol/L after 24 h. Samples with leukocytosis (neutrophil counts 23 x 10(9)-52 x 10(9)/L) were also stable, with a mean increase of 0.3 mmol/L at 8 h. Use of the antiglycolytic agents F and OX (at 60 and 12 mmol/L, respectively) maintained apparently stable lactate concentrations at room temperature for up to 8 h without special handling.

scholarly journals Intra-arterial AICA-riboside administration induces NO-dependent vasodilation in vivo in human skeletal muscle

2009 ◽  
Vol 297 (3) ◽  
pp. E759-E766 ◽  
Author(s):  
Marlies Bosselaar ◽  
Hanneke Boon ◽  
Luc J. C. van Loon ◽  
Petra H. H. van den Broek ◽  
Paul Smits ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Plasma Concentrations ◽  
Metabolic Effects ◽  
Nucleoside Transporter ◽  
In Vitro Experiments

In animal models, administration of the adenosine analog AICA-riboside has shown beneficial effects on ischemia-reperfusion injury and glucose homeostasis. The vascular and/or metabolic effects of AICA-riboside administration in humans remain to be established. AICA-riboside was infused intra-arterially in four different dosages up to 8 mg·min−1·dl−1 in 24 healthy subjects. Forearm blood flow (FBF) and glucose uptake and plasma glucose, free fatty acid, and AICA-riboside concentrations were assessed. We also combined AICA-riboside infusion (2 mg·min−1·dl−1) with the intra-arterial administration of the adenosine receptor antagonist caffeine (90 μg·min−1·dl−1; n = 6) and with the endothelial NO synthase inhibitor l-NMMA (0.4 mg·min−1·dl−1; n = 6). Additional in vitro experiments were performed to explain our in vivo effects of AICA-riboside in humans. AICA-riboside increased FBF dose dependently from 2.0 ± 0.2 to 13.2 ± 1.9 ml·min−1·dl−1 maximally ( P < 0.05 for all dosages). The latter was not reduced by caffeine administration but was significantly attenuated by l-NMMA infusion. Despite high plasma AICA-riboside concentrations, forearm glucose uptake did not change. In vitro experiments showed rapid uptake of AICA-riboside by the equilibrative nucleoside transporter in erythrocytes and subsequent phosphorylation to AICA-ribotide. We conclude that AICA-riboside induces a potent vasodilator response in humans that is mediated by NO. Despite high local plasma concentrations, AICA-riboside does not increase skeletal muscle glucose uptake.

scholarly journals Germination Characteristics and Dynamic Changes of Antioxidant Enzymes during Storage of Viola dissecta Pollen

2021 ◽  
Vol 25 (04) ◽  
pp. 838-844
Author(s):  
Wenqing Jia
Keyword(s):  
Antioxidant Enzymes ◽  
Pollen Germination ◽  
Room Temperature ◽  
Storage Temperature ◽  
Germination Rate ◽  
Pollen Grains ◽  
Suitable Medium ◽  
Different Temperatures ◽  
Surface Ornamentation

Knowledge about pollen ultra-morphology, storage characteristics and germination rate are essential for directional plant breeding and plant improvement. The objective of this study was to determine a suitable medium for pollen germination in vitro of Viola dissecta and to evaluate the effect of different storage temperatures on its pollen longevity. The pollen ultra-morphology of V. dissecta was observed using scanning electron microscopy (SEM), the suitable medium for pollen germination in vitro was determined by orthogonal test. Dried pollen of V. dissecta was stored at different temperatures (room temperature, 4, -20 and -80°C) and different storage times (24, 40, 72, 120, 184, 264 and 365 d), the germination rate of the stored pollen and the activities of SOD, POD and CAT were investigated. Pollen grains of V. dissecta were medium-sized with three germination ditches. The surface ornamentation was smooth with small grains set on the surface, which was different from Viola spp. pollen. The most suitable medium for V. dissecta was composed of 285 g•L-1 sucrose, 6 g•L-1 agar, 50 mg•L-1 GA3, 250 mg•L-1 boric acid, and 200 mg•L-1 Ca(NO3)2, The best storage temperature of pollen was -80oC, after 365 d of storage, the germination rate was still 57.86%. During storage, the pollen germination rate decreased significantly after the peak of the activities of the three antioxidant enzymes. Correlation analysis showed that SOD was major factor affecting the germination rate of V. dissecta pollen, and it has a significant positive correlation with pollen germination rate, followed by CAT and POD. SOD was a sensitive antioxidant enzyme at room temperature, 4 and -80°C, whereas at -20°C, both SOD and CAT were sensitive antioxidant enzymes. © 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers © 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers© 2021 Friends Science Publishers©

Effect of exercise on lipolytic sensitivity in endurance-trained athletes

1995 ◽  
Vol 78 (6) ◽  
pp. 2201-2206 ◽  
Author(s):  
S. Klein ◽  
E. F. Coyle ◽  
R. R. Wolfe
Keyword(s):  
High Intensity ◽  
Lipolytic Activity ◽  
Whole Body ◽  
Adrenergic Stimulation ◽  
Epinephrine Infusion ◽  
Beta Adrenergic ◽  
Ergometer Exercise ◽  
Plasma Ffa

Studies performed in vitro suggest that an acute bout of exercise increases the lipolytic response to beta-adrenergic stimulation. We evaluated the effect of exercise on lipolytic sensitivity in vivo in five endurance-trained athletes. The rate of appearance (Ra) of glycerol in plasma, an index of whole body lipolysis, was determined during 60 min of epinephrine infusion (0.015 microgram.kg-1.min-1) on two occasions: 1) at basal resting conditions and 2) 90 min after completing 1 h of high-intensity (70% O2 uptake) cycle ergometer exercise. Total glycerol Ra during epinephrine infusion in the basal state (352 +/- 35 mumol.kg-1. 60 min-1) was not significantly different from the value obtained after high-intensity exercise (439 +/- 58 mumol.kg-1. 60 min-1). However, the increase in glycerol Ra above baseline during epinephrine infusion was lower after (30 +/- 16 mumol.kg-1. 60 min-1) than before (148 +/- 28 mumol.kg-1. 60 min-1) exercise because of the high postexercise baseline value (P < 0.05). Mean plasma free fatty acid (FFA) concentration was lower during exercise than during epinephrine infusion despite a greater rate of lipolysis during exercise. The slope of change in plasma FFA with respect to glycerol RA was lower during exercise (0.0171 +/- 0.006) than during epinephrine infusion (0.0835 +/- 0.018) (P < 0.05). We conclude that a single bout of intense exercise does not increase in vivo lipolytic sensitivity to beta-adrenergic stimulation in endurance-trained athletes. In addition, plasma FFA concentration represents the balance between plasma FFA inflow and tissue uptake and cannot be used as an index of lipolytic activity during certain physiological conditions, such as exercise.

Comparison of the effects of in vitro and in situ storage on the viability of mouse ovarian tissue collected after death

2001 ◽  
Vol 13 (6) ◽  
pp. 389 ◽  
Author(s):  
M. Snow ◽  
M. Cleary ◽  
S-L. Cox ◽  
J. Shaw ◽  
M. Paris ◽  
...  
Keyword(s):  
Room Temperature ◽  
Storage Temperature ◽  
Ovarian Tissue ◽  
The Body ◽  
Tissue Storage ◽  
Duration Of Storage ◽  
The Impact ◽  
Phosphate Buffered Saline

Ovarian tissues, collected or salvaged from endangered species at the time of gonadectomy or following their death, are being transported to genebanks for storage with the assumption that they will (subsequently) yield sufficient numbers of germ cells to help preserve the species. The present study aimed to quantify the impact of delays in collecting and/or processing ovarian tissue on the number of follicles in this tissue that remained normal after grafting. The study compared the viability of ovarian tissue stored in vitro (in phosphate-buffered saline) versus in situ (in the body) either on ice or at room temperature for 0 (non-stored fresh grafts), 3, 6, 12, 24 or 48 h. The conditions of storage had significant effects on the total number of morphologically normal follicles, with significantly more follicles in grafts developing from in vitro-stored tissue than in situ-stored tissue. Storage temperature and duration of storage, but not the storage temperature alone, influenced follicle survival. Tissue that was grafted immediately after collection (0 h) was best, but normal follicles were recovered in grafts stored in vitro (on ice or at room temperature) or in situ (on ice only) for up to 48 h before grafting. The rate of follicle loss over time was very rapid, with approximately 50% fewer follicles in grafts derived from tissue stored for only 3 h compared with non-stored fresh grafts (0 h). The results show that viable ovarian tissue can be salvaged from animals up to 48 h after death; however, in order to best protect the follicle population, the ovaries should be removed from the animal’s body as soon as possible.

scholarly journals Storage temperature determines platelet GPVI levels and function in mice and humans

2021 ◽  
Author(s):  
Jeffrey Miles ◽  
S. Lawrence Bailey ◽  
Ava M Obenaus ◽  
Molly Y Mollica ◽  
Chomkan Usaneerungrueng ◽  
...  
Keyword(s):  
Cold Storage ◽  
Cold Exposure ◽  
Room Temperature ◽  
Storage Temperature ◽  
Storage Duration ◽  
Functional Consequences ◽  
And Function ◽  
Contractile Forces

Platelets are currently stored at room temperature before transfusion to maximize circulation time. This approach has numerous downsides, including limited storage duration, bacterial growth risk, and increased costs. Cold storage could alleviate these problems. However, the functional consequences of cold exposure for platelets are poorly understood. In the present study, we compared the function of cold-stored platelets (CSP) and room temperature-stored platelets (RSP) in vitro, in vivo, and post-transfusion. CSP formed larger aggregates under in vitro shear while generating similar contractile forces compared to RSP. We found significantly reduced GPVI levels after cold exposure of 5-7 days. After transfusion in humans, CSP were mostly equivalent to RSP yet aggregated significantly less to the GPVI agonist collagen. In a mouse model of platelet transfusion, we found a significantly lower response to the GPVI-dependent agonist convulxin and significantly lower GPVI levels on the surface of transfused platelets after cold storage. In summary, our data support an immediate but short-lived benefit of CSP and highlight the need for thorough investigations of this product. (NCT03787927)

scholarly journals Impact of Storage Temperature on Pollen Viability and Germinability of Four Serbian Autochthon Apple Cultivars

2021 ◽  
Vol 12 ◽  
Author(s):  
Dušica Ćalić ◽  
Jelena Milojević ◽  
Maja Belić ◽  
Rade Miletić ◽  
Snežana Zdravković-Korać
Keyword(s):  
Room Temperature ◽  
Storage Temperature ◽  
Pollen Viability ◽  
Storage Period ◽  
Pollen Storage ◽  
Apple Cultivars ◽  
Pollen Longevity ◽  
Fresh Pollen ◽  
Storage Temperatures

Globalization has drastically reduced the number of autochthon apple cultivars in the Serbian market and most of them have nearly disappeared; however, some of these cultivars, such as Petrovača, Budimka, Kolačara Pozna, and Kožara, have extraordinary quality, good pomological characteristics, and pest and disease resistance. The present study was conducted to develop a protocol for the storage of pollen for further use in the conservation and breeding of these cultivars. Viability and germination of the mature pollen were tested in vitro, at four storage temperatures (20, 4, −20, and −80°C), right after harvest or 1, 2, 3, 4, 5, and 6 months after storage. Differences in fresh pollen viability and germination between cultivars were statistically significant and ranged from 60 to 88% and 59 to 98%, respectively. Fresh pollen of cv. Budimka showed the highest viability and germination in comparison with other cultivars, especially cv. Kožara. Pollen viability and germination decreased over the storage period, and it was the lowest after 6 months of storage at room temperature in all tested cultivars. Storage at 4°C prolonged the pollen viability and germinability of 1–5 fold, depending on the cultivar and treatment duration; however, the pollen longevity of all cultivars was significantly extended when stored at −20 or −80°C. After 6 months, pollen of cv. Budimka stored at −20 and −80°C showed 14–15 fold higher germination rates in relation to pollen storage at room temperature for the same period. The results of the present study suggest that the pollen of these apple cultivars could be efficiently maintained at −20°C and could be further used for breeding purposes, e.g., for crossings between cultivars that flower at different times of the year.

scholarly journals Lipolytic response of adipose tissue and metabolic adaptations to long periods of fasting in red tilapia (Oreochromis sp., Teleostei: Cichlidae)

2016 ◽  
Vol 88 (3 suppl) ◽  
pp. 1743-1754 ◽  
Author(s):  
WALTER DIAS JUNIOR ◽  
AMANDA M. BAVIERA ◽  
NEUSA M. ZANON ◽  
VICTOR D. GALBAN ◽  
MARIA ANTONIETA R. GARÓFALO ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Plasma Glucose ◽  
Lipolytic Activity ◽  
Phosphodiesterase Inhibitor ◽  
Liver Glycogen ◽  
Camp Phosphodiesterase ◽  
Red Tilapia ◽  
Glucose Levels ◽  
Plasma Ffa

ABSTRACT Adaptive changes of carbohydrate and lipid metabolism induced by 7, 15, 30, 60, 90, 150 and 200 days of fasting were investigated in red tilapia (Oreochromis sp.). Plasma glucose, lactate and free fatty acids (FFA) levels, liver and muscle glycogen and total lipid contents and rates of FFA release from mesenteric adipose tissue (MAT) were measured. Plasma glucose levels showed significant differences only after 90 days of fasting, when glycemia was 34% lower (50±5mg.dL-1) than fed fish values (74±1mg.dL-1), remaining relatively constant until 200 days of fasting. The content of liver glycogen ("15%) in fed tilapia fell 40% in 7 days of food deprivation. In 60, 90 and 150 days of fasting, plasma FFA levels increased 49%, 64% and 90%, respectively, compared to fed fish values. In agreement with the increase in plasma FFA, fasting induced a clear increase in lipolytic activity of MAT incubated in vitro. Addition of isobutylmethylxanthine (cAMP-phosphodiesterase inhibitor) and isoproterenol (non selective beta adrenergic agonist) to the incubation medium induced a reduction of lipolysis in fasted fish, differently to what was observed in mammal adipose tissue. This study allowed a physiological assessment of red tilapia response to starvation.

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