0000000000276732
AUTHOR
Eduards Sevostjanovs
Decreases in Circulating Concentrations of Long-Chain Acylcarnitines and Free Fatty Acids During the Glucose Tolerance Test Represent Tissue-Specific Insulin Sensitivity
Background: Insulin plays a pivotal role in the regulation of both carbohydrate and lipid intermediate turnover and metabolism. In the transition from a fasted to fed state, insulin action inhibits lipolysis in adipocytes, and acylcarnitine synthesis in the muscles and heart. The aim of this study was to measure free fatty acid (FFA) and acylcarnitine levels during the glucose tolerance test as indicators of tissue-specific insulin resistance. Results: Insulin release in response to glucose administration decreased both FFA and long-chain acylcarnitine levels in plasma in healthy control animals by 30% (120 min). The glucose tolerance test and [3H]-deoxy-D-glucose uptake in tissues revealed…
4-(3,-Piridil) piridīna atvasinājumu sorbcijas pētījumi augsti efektīvajā šķidrumu hromatogrāfijā
Darbā ir apkopota literatūra par piridīna atvasinājumu hromatogrāfiskajām analīzes metodēm. Balstoties uz literatūras datiem, izvēlēti savienojumu analīzes apstākļi un izvērtētas kustīgās fāzes sastāva un pH, kolonnas temperatūras, stacionārās fāzes īpašību ietekme uz analizējamo vielu kapacitātes faktoriem, joslu asimetriju, teorētisko šķīvju skaitu, izšķiršanu. Darbā iegūtie rezultāti var atvieglot analīzes apstākļu izvēli turpmākiem 4-(3’-piridil) piridīna atvasinājumu pētījumiem ar šķidrumu hromatogrāfijas / masspektrometrijas metodēm.
Mildronate, the inhibitor of l-carnitine transport, induces brain mitochondrial uncoupling and protects against anoxia-reoxygenation
Abstract The preservation of mitochondrial function is essential for normal brain function after ischaemia-reperfusion injury. l -carnitine is a cofactor involved in the regulation of cellular energy metabolism. Recently, it has been shown that mildronate, an inhibitor of l -carnitine transport, improves neurological outcome after ischaemic damage of brain tissues. The aim of the present study was to elucidate the mitochondria targeted neuroprotective action of mildronate in the model of anoxia-reoxygenation-induced injury. Wistar rats were treated daily with mildronate ( per os ; 100 mg/kg) for 14 days. The acyl-carnitine profile was determined in the brain tissues. Mitochondrial respirati…
Low-intensity exercise stimulates bioenergetics and increases fat oxidation in mitochondria of blood mononuclear cells from sedentary adults.
Aim Exercise training induces adaptations in muscle and other tissue mitochondrial metabolism, dynamics, and oxidative phosphorylation capacity. Mitochondrial fatty acid oxidation was shown to be pivotal for the anti‐inflammatory status of immune cells. We hypothesize that exercise training can exert effects influence mitochondrial fatty acid metabolism in peripheral blood mononuclear cells (PBMCs). The aim was to investigate the effect of exercise on the fatty acid oxidation‐dependent respiration in PBMCs. Design Twelve fasted or fed volunteers first performed incremental‐load exercise tests to exhaustion on a cycle ergometer to determine the optimal workload ensuring maximal health benefi…
Trimetillizīna kvantitatīva noteikšana bioloģiskos paraugos ar šķidrumu hromatogfāfijas-masspektrometrijas metodi
Darbā apkopota literatūra par trimetillizīna kvantitatīvās analīzes iespējām ar šķidrumu hromatogrāfijas metodēm. Izstrādāta un validēta jauna šķidrumu hromatogrāfijas – tandēmmasspektrometrijas metode trimetillizīna kvantitatīvai noteikšanai bioloģiskos paraugos, izmantojot derivatizāciju ar 6-aminohinolil-N-hidroksisukcīnimidilkarbamātu. Izstrādātā metode sekmīgi pielietota karnitīna biosintēzē iesaistīto savienojumu koncentrāciju mērījumiem žurku asins plazmā un audu homogenātos.
Rats with congenital hydronephrosis show increased susceptibility to renal ischemia‐reperfusion injury
Abstract Many drug candidates have shown significant renoprotective effects in preclinical models; however, there is no clinically used effective pharmacotherapy for acute kidney injury. The failure to translate from bench to bedside could be due to misleading results from experimental animals with undetected congenital kidney defects. This study was performed to assess the effects of congenital hydronephrosis on the functional capacity of tubular renal transporters as well as kidney sensitivity to ischemia‐reperfusion (I‐R)‐induced injury in male Wistar rats. Ultrasonography was used to distinguish healthy control rats from rats with hydronephrosis. L‐carnitine or furosemide was administer…
Determination of trimethylamine-N-oxide in combination withl-carnitine andγ-butyrobetaine in human plasma by UPLC/MS/MS
An ultra-high-performance liquid chromatography-mass spectrometry (UPLC/MS/MS) method was developed and validated for the quantification of trimethylamine-N-oxide (TMAO) simultaneously with TMAO-related molecules L-carnitine and γ-butyrobetaine (GBB) in human blood plasma. The separation of analytes was achieved using a Hydrophilic interaction liquid chromatography (HILIC)-type column with ammonium acetate-acetonitrile as the mobile phase. TMAO determination was validated according to valid US Food and Drug Administration guidelines. The developed method was successfully applied to plasma samples from healthy volunteers.
CntA oxygenase substrate profile comparison and oxygen dependency of TMA production in Providencia rettgeri.
CntA oxygenase is a Rieske 2S-2Fe cluster-containing protein that has been previously described as able to produce trimethylamine (TMA) from carnitine, gamma-butyrobetaine, glycine betaine, and in one case, choline. TMA found in humans is exclusively of bacterial origin, and its metabolite, trimethylamine oxide (TMAO), has been associated with atherosclerosis and heart and renal failure. We isolated four different Rieske oxygenases and determined that there are no significant differences in their substrate panels. All three had high activity toward carnitine/gamma-butyrobetaine, medium activity toward glycine betaine, and very low activity toward choline. We tested the influence of low oxyg…