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EN
The Lipoprint system (Quantimetrix Corp., CA, USA), enables the determination of 10 high density lipoprotein (HDL) subfractions in contrast to the 5 HDL subfractions that can be determined by ultracentrifuge analysis. HDL subfractions, and their relationships to the arylesterase (PON1-A) and lactonase (PON1-L) activities of paraoxonase 1 (PON1), together with total-, very low density lipoprotein- and low density lipoprotein (LDL)-cholesterol and LDL subfractions were investigated in the serum of 27 mildly hypercholesterolemic children and 21 healthy controls. Our results suggest the antiatherogenity of large HDL (L-HDL) subfractions and the atherogenity of small HDL (S-HDL) subfractions in the study groups. However, the relationship between the intermediate HDL (I-HDL) subfractions with the LDL subfractions and other lipoproteins did not suggest that I-HDL subfractions are antiatherogenic. No significant association between PON1-A and the HDL subfractions was found. In contrast, PON1-L activity positively correlated with the antiatherogenic large HDL1 subfraction and negatively with intermediate HDL subfractions 4, 5 and 6. Our results contribute to the knowledge of the roles of total HDL and ten individual HDL subfractions in children and adolescents.
EN
Introduction: The statin-induced effects on high density lipoprotein (HDL) are relatively small compared with those of low density lipoprotein (LDL) and, as a result, most clinical trials of statins are underpowered with respect to HDL parameters. This study experimentally investigated, the effects of statin on serum lipids, atherogenic index and examined the possibility of a relationship amongst serum concentrations of HDL-C, atherogenic index and activity of lecithin:cholesterol acyl transferase. Method: Thirty albino rats equally divided into 2 groups were used for the study. Group 1 was given 0.05mg/g of statin daily for 28 days, while group 2 served as control. HDL concentration was determined as a measure of HDL-C. Total cholesterol (TC), triglyceride (TG) and HDL-C were determined spectrophotometrically while LDL-C was calculated using the Frieldwald formula. Effect on the activity of lecithin:cholesterol acyl transferase was determined by the difference between the amount of free cholesterol converted to cholesteryl ester in the two experimental groups. Effects on body and relative organs weights were also determined. Results: The administration of statin caused a significant increase in serum concentration of HDL-C, while levels of LDL-C, triglyceride and total cholesterol were reduced. Simvastatin caused a significant reduction in the atherogenic index (TC/HDL-C; LDLC/HDL-C). The administration of statin significantly induced the activity of lecithin:cholesterol acyl transferase (LCAT) as evident by reduced serum concentration of free cholesterol when compared with control. The administration of statin caused reduced body and relative organs weights. Conclusion: The study showed that serum antihyperlipidemic and antiatherogenic activity of statin may involve the induction of LCAT.
EN
Our study was aimed at the evaluation of relationships between thyroid stimulating hormone (TSH) within the normal range and metabolic risk factors (glucose, insulin, HOMA-IR and lipoprotein profile) in physically active male and female students. In 219 students circulating TSH, glucose, insulin and lipoproteins were measured in blood under fasting conditions. Insulin resistance was expressed as HOMA-IR (homeostasis model assessment for insulin resistance). For further procedures 99 males and 97 regularly menstruating females with TSH 0.4–4.0 μIU/ml were accepted. In male students no correlations between circulating TSH, anthropometric and biochemical variables were noted. In females TSH within the normal range was slightly but significantly correlated with the triglyceride (TG) level (p < 0.03). However, step-wise multiple regression analysis revealed that the effect of TSH was small (p < 0.046) in relation to that found for HOMA-IR ( p < 0.0009). No relationships between biochemical variables and normal levels of TSH were noted in male students. However, surprisingly normal range TSH in males was slightly but significantly correlated with the percentage of body fat and this issue needs further studies concerning measurements of different fat depots. The above data suggests that in active females TG synthesis and export from the liver is more sensitive to TSH action than in active male counterparts.
4
100%
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vol. 27
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issue 4
209-212
EN
Heparan sulfate (HS) is one of the most common glycosaminoglycan (GAG) in mammals. It is composed of relatively simple disaccharide subunits, which, by further modification, such as sulfation and epimerization, potentially offer huge diversity in biological function. GAG chains of different length, different patterns of sulfation, and other modifications, depending on location, generate unique forms. Due to polyanion charges, these compounds can interact with other molecules, such as proteins, cytokines, chemokines and growth factors, both on the cell surface and inside the extracellular matrix. These interactions serve protective and storage functions for the compounds, safeguarding them from proteolysis. In this way, HS is involved in numerous signaling pathways, and in growth and differentiation processes. Disrupted interactions between the HS and growth factors, cytokines or other proteins have been observed in various disorders, among these Alzheimer’s disease, epilepsy, atherosclerosis, diabetes, and cancer processes. Detailed knowledge of these relationships at the molecular level will allow researchers to understand the mechanisms underlying these disorders and enable the development of effective therapeutic strategies.
EN
Background. There is an increasing interest in the role of adipocytokines in cardiovascular pathophysiology. Aim. The aim of the study was to compare visfatin levels, a novel adipokine, in patients with heart failure (HF) due to the left ventricular systolic dysfunction with those in age- and body mass index (BMI) - matched healthy controls in relation to the parameters of glucose metabolism and high sensitivity C-reactive protein (hsCRP) levels. Material/Subjects and Methods. The study population consisted of 28 males with systolic HF referred for cardiopulmonary exercise testing, divided into two subgroups based on their NYHA class (HF patients NYHAI+II, n=17, and HF patients NYHAIII+IV, n=11), and 23 controls. The following indices were measured in a serum samples: visfatin, hsCRP, glucose and lipid metabolism parameters, and the insulin resistance index HOMAIR (homeostasis model assessment insulin resistance) was calculated. Results. Concentrations of visfatin and high-density lipoprotein cholesterol (HDL-cholesterol) in the HF subjects were significantly lower (p≤0.01) than in controls. The Kruskal-Wallis test showed significant differences between three groups (controls and both subgroups of heart failure patients) in mean levels of visfatin, hsCRP, glucose, HOMAIR and HDL-cholesterol. Conclusion. Serum visfatin concentrations in patients with systolic HF, particularly with more advanced NYHA classes, are significantly lower in comparison to healthy controls and are independent of age or anthropometric and metabolic parameters.
EN
The aim of the study was to examine concentrations and relationships between melatonin levels assessed at 0:200 hrs and 0:700 hrs, lipid hydroperoxide (LPO) assessed at 0:200 hrs and 0:700 hrs, and apolipoprotein (apo)AI, apoAII, apoB, high sensitivity C-reactive protein (hsCRP) and NT-proBNP, in 27 patients with chronic heart failure (CHF) (17 patients - with NYHA class II and 10 - with NYHA class III). In the study, Lipoproteins apoAI, apoAII, apoB, high sensitivity C-reactive protein (hsCRP) levels were determined by way of immunonephelometric methods, serum melatonin concentration was measured by using a competitive enzyme immunoassay technique, while serum LPO concentration was measured by using Cayman’s Lipid Hydroperoxide Assay Kit. In the study, CHF patients without acute inflammatory response demonstrated a decreased concentration of high density lipoprotein cholesterol (HDL-C), apoAI, apoAII levels, but an increased concentration of NT-proBNP, hsCRP and LPO at night, and LPO at daytime; however, the concentration of LPO at 0:700 was lower than at 0:200. Pearson’s correlation test and multiple ridge stepwise regression showed that melatonin administered at night exerts an effect on the composition of apoAI and apoAII of HDL particles, and induces decreased LPO at 0:700, but has no effect upon NT-proBNP levels in patients with NYHA class II. However, in patients with NYHA class III, melatonin administered at night induces an increase in the content of apoAII and apoAI, which further decreases hsCRP, and this, together with the administered melatonin, brings about daytime decreases in NT-proBNP and hsCRP levels. The results indicated that the content of apoAII and apoAI in HDL particles and melatonin demonstrate an anti-oxidative and anti-inflammatory effect, and together, have a cardio-protective effect on patients with advanced CHF. Hence, the results support melatonin being a cardio-protective agent. These relationships, however, need to be confirmed in further studies.
EN
Preeclampsia, hemorrhage, and infection are the leading causes of maternal death in underdeveloped countries. Since several proteins associated with preeclampsia are known, we conducted a computational study which evaluated the commonness and potential functionality of intrinsic disorder of these proteins and also made an attempt to characterize their origin. The origin of the preeclampsia-related proteins was assessed with a supervised technique, a Polarity Index Method (PIM), which evaluates the electronegativity of proteins based solely on their sequence. The commonness of intrinsic disorder was evaluated using several disorder predictors from the PONDR family, the charge-hydropathy plot (CH-plot) and cumulative distribution function (CDF) analyses, and using the MobiDB web-based tool, whereas potential functionality of intrinsic disorder was studied with the D2P2 resource and ANCHOR predictor of disorder-based binding sites, and the STRING tool was used to build the interactivity networks of the preeclampsia-related proteins. Peculiarities of the PIM-derived polar profile of the group of preeclampsia-related proteins were then compared with profiles of a group of lipoproteins, antimicrobial peptides, angiogenesis-related proteins, and the intrinsically disordered proteins. Our results showed a high graphical correlation between preeclampsia proteins, lipoproteins, and the angiogenesis proteins. We also showed that many preeclampsia-related proteins contain numerous functional disordered regions. Therefore, these bioinformatics results led us to assume that the preeclampsia proteins are highly associated with the lipoproteins group, and that some preeclampsia-related proteins contain significant amounts of functional disorders.
EN
The lipoproteins are an important group of cargo proteins known for their unique capability to transport lipids. By applying the Polarity index algorithm, which has a metric that only considers the polar profile of the linear sequences of the lipoprotein group, we obtained an analytical and structural differentiation of all the lipoproteins found in UniProt Database. Also, the functional groups of lipoproteins, and particularly of the set of lipoproteins relevant to atherosclerosis, were analyzed with the same method to reveal their structural preference, and the results of Polarity index analysis were verified by an alternate test, the Cumulative Distribution Function algorithm, applied to the same groups of lipoproteins.
Kosmos
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2018
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vol. 67
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issue 2
375-390
PL
Cholesterol to cząsteczka zbudowana z 17-węglowej struktury cyklopentanoperhydrofenantrenu i dołączonego do niej 6-węglowego łańcucha bocznego, klasyfikowana jako alkohol steroidowy ze względu na obecność pojedynczej grupy hydroksylowej. Główną funkcją cholesterolu jest zależna od temperatury modulacja płynności błon komórkowych. Duża ilość cholesterolu występuje w nanodomenach błonowych (tratwach lipidowych i kaweolach), które pełnią ważną rolę w procesie endocytozy i przekaźnictwie międzykomórkowym. Ponadto, jest on prekursorem hormonów steroidowych produkowanych przez gonady i korę nadnerczy oraz warunkuje właściwy przebieg rozwoju embrionalnego. Poza pełnieniem istotnej roli fizjologicznej, cholesterol może przyczyniać się do rozwoju wielu stanów patologicznych, wynikających zarówno z nagromadzenia jego cząsteczek w ustroju, jak i zaburzeń ich metabolizmu. Jego udział opisano m.in. w rozwoju schorzeń neurodegeneracyjnych, chorób układu krążenia, chorób nerek oraz chorób nowotworowych. Obecnie prowadzone badania zmierzają do opracowania nowych strategii terapeutycznych, pozwalających na skuteczniejszą i bezpieczniejszą kontrolę poziomu cholesterolu i regulację jego metabolizmu, oraz mających na celu wykorzystanie cholesterolu jako składnika nowych, skuteczniejszych leków.
EN
Cholesterol is a molecule build of 17-carbon cyclopentano-perhydro-phenanthrene structure and 6- carbon side chain, classified as steroid alcohol due to the presence of a single hydroxyl group. The main function of cholesterol is temperature-dependent modulation of cell membrane liquidity. Large amounts of cholesterol are found in membrane nanodomains (lipid rafts and caveolae) that are essential for endocytosis and intercellular signaling. Moreover, cholesterol is a substrate in steroid hormones biosynthesis in gonads and adrenal glands, and determines the proper course of embryonic development. Besides its physiological role, cholesterol may contribute to pathogenesis of different diseases, resulting from its accumulation in the system or from metabolic disorders. The significance of cholesterol has already been described in several neurodegenerative disorders, cardiovascular and renal diseases, and in cancer. Therefore, current research focus on providing some new therapeutic strategies, allowing for cholesterol level control, regulation of its metabolism, or for using cholesterol molecules as effective drug component.
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