Evaluation of the functioning of long-term at-home nursing care in Poland from the perspective of care providers: Mixed methods study.

AIMS AND OBJECTIVES: This study aimed to analyse and evaluate the functioning of long-term at-home nursing care (LTHNC) based on the opinions of its service providers. BACKGROUND: Long-term at-home nursing care is a form of care for patients who do not need hospital treatment but need systematic nursing care because of their health problems. LTHNC in Poland involves guaranteed care services financed from universal health insurance contributions pursuant to contracts with the National Health Fund (NHF); the program has existed since 2004. DESIGN: A sequential-explanatory mixed-method design was used. The study was carried out using both quantitative and qualitative research methods. METHODS: A questionnaire was distributed amongst 1119 care providers (the response rate was 38.2%). The qualitative research comprised semi-structured interviews with ten care providers, namely three nurses managing LTHNC facilities and seven nurses directly providing services as part of LTHNC. The STROBE checklist was used in reporting this study. RESULTS: We found that the main reasons for contracting LTHNC services were the increasing demand for this form of care, financial motives and an opportunity to introduce new organisational solutions. Our study shows that LTHNC is beneficial not only for the patients, but also for the nurses who provide the care. On the one hand, LTHNC provides positive results for patients and their caregivers (family members), and on the other hand, it affords a sense of satisfaction to the nurses and contributes to the development of their professional independence. CONCLUSIONS: According to care providers, improving accessibility through increasing the number of contracted services as well as raising the pay for 1 day of care per patient may improve the functioning of LTHNC. RELEVANCE TO CLINICAL PRACTICE: The results of our study are a source of information for those who organise health care and administer resources on how to improve the functioning of LTHNC.

Multivessel Coronary Artery Disease Complicated by Diabetes Mellitus Has a Relatively Small Effect on Endothelial and Lipoprotein Lipases Expression in the Human Atrial Myocardium and Coronary Perivascular Adipose Tissue.

Endothelial (EL) and lipoprotein (LPL) lipases are enzymes involved in lipoproteins metabolism and formation of atherosclerosis, a pathological feature of coronary artery disease (CAD). This paper examines the role of the lipases in the right atrial appendage (RAA) and coronary perivascular adipose tissue (PVAT) of patients with CAD alone or with accompanying diabetes. Additionally, correlation analysis for plasma concentration of the lipases, apolipoproteins (ApoA-ApoJ) and blood lipids (Chol, HDL-C, LDL-C, TAG) was performed. We observed that CAD had little effect on the lipases gene/protein levels in the RAA, while their transcript content was elevated in the PVAT of diabetic CAD patients. Interestingly, the RAA was characterized by higher expression of EL/LPL (EL: +1-fold for mRNA, +5-fold for protein; LPL: +2.8-fold for mRNA, +12-fold for protein) compared to PVAT. Furthermore, ApoA1 plasma concentration was decreased, whereas ApoC1 and ApoH were increased in the patients with CAD and/or diabetes. The concentrations of ApoC3 and ApoD were strongly positively correlated with TAG content in the blood, and the same was true for ApoB with respect to LDL-C and total cholesterol. Although plasma concentrations of EL/LPL were elevated in the patients with diabetes, CAD alone had little effect on blood, myocardial and perivascular fat expression of the lipases.

The Interplay between Bioactive Sphingolipids in the Psoriatic Skin and the Severity of the Disease.

Psoriasis is a complex chronic immunologically mediated disease that may involve skin, nails, and joints. It is characterized by hyperproliferation, deregulated differentiation, and impaired apoptosis of keratinocytes. Sphingolipids, namely ceramide, sphingosine-1-phosphate, sphingosine, sphingomyelin, and sphinganine-1-phosphate, are signal molecules that may regulate cell growth, immune reactions, and apoptosis. Fifteen patients with psoriasis and seventeen healthy persons were enrolled in the study. Skin samples were taken from psoriatic lesions and non-lesional areas. Tissue concentration of ceramides, sphingosine-1-phosphate, sphingosine, sphingomyelin, and sphinganine-1-phosphate was measured by liquid chromatography. We assessed that all levels of ceramides, sphingosine-1-phosphate, sphingosine, sphingomyelin, and sphinganine-1-phosphate were higher in lesioned psoriatic skin than in non-affected skin. The profile of bioactive lipids in the lesional skin of patients with psoriasis differed significantly from non-involved psoriatic skin and skin in healthy subjects.

Crosstalk between Serum and Skin Sphingolipids in Psoriasis.

Psoriasis is a chronic, complex, immunological disorder, which may lead to many different systemic complications. Sphingolipids, including ceramide, are bioactive lipids, which take part in the regulation of immune reactions, cell growth, and apoptosis. Twenty psoriatic patients and twenty-eight control subjects were included in the study. Skin (both lesional and non-lesional) and serum samples were collected from both the control group and the psoriatic patients. The levels of sphingosine (SFO), sphingosine-1-phosphate (S1P), sphingomyelin, sphinganine (SFA), sphinganine-1-phosphate (SFA1P), and ceramide (CER) were assessed in both tissue (t) and serum (s) samples using high-performance liquid chromatography (HPLC). We identified elevated serum levels of SFO, S1P, SFA, and SFA1P in psoriatic patients when compared to healthy individuals. As far as the lesional skin and serum of psoriatic patients are concerned, we demonstrated positive associations between CER_t and CER_s, SFA_t and CER_s, and SFO_t and CER_s. Additionally, we found negative correlations in the non-lesional skin and serum of psoriatic patients, including SFO_t vs. SFO_s, CER_t vs. SFA_s, CER_t vs. SFO_s, and SFO_t vs. SFA_s. Finally, we observed a positive correlation between S1P and SFA1P in both the serum samples of psoriatic patients and the serum samples of the control group. In this study, we did not observe any correlations between psoriasis area and severity index (PASI) scores and sphingolipid levels. In conclusion, our findings indicate an interplay between skin and serum lipids in psoriatic patients, which is not observed in healthy individuals.

Diverse Impact of N-Acetylcysteine or Alpha-Lipoic Acid Supplementation during High-Fat Diet Regime on Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 in Visceral and Subcutaneous Adipose Tissue.

BACKGROUND/AIMS: The high-fat diet (HFD) regime causes obesity and contributes to the development of oxidative stress in the cells by the production of reactive oxygen species and the occurrence and progress of inflammation. Despite years of studies, there is no data explaining the mechanism of action of N-acetylcysteine (NAC) or alpha-lipoic acid (ALA) on matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9) in visceral and subcutaneous adipose tissue of HFD-fed rats. Our experiment aimed to evaluate for the first time the influence of chronic antioxidants administration on MMPs biology after an HFD regime as a potential therapeutic strategy for obesity-related complications prevention. METHODS: Male Wistar rats were fed a standard rodent chow or an HFD with intragastric administration of NAC or ALA for ten weeks. The collected samples were subjected to pathohistological evaluation. Real-time PCR and western blot approaches were used to check whether NAC or ALA impacts MMP2/9 expression. RESULTS: Antioxidant supplementation markedly reduced the number of circulating inflammatory cytokines, and tissue macrophage infiltration. Moreover, NAC and ALA have a divergent impact on MMP2 and MMP9 expression in different adipose tissue localization. CONCLUSION: Based on our results, we speculate that NAC and ALA have a prominent effect on the MMP2/9 functions under obesity conditions.

Dose- and time-dependent alterations in lipid metabolism after pharmacological PGC-1α activation in L6 myotubes.

Pyrroloquinoline quinone (PQQ) acts as a powerful modulator of PGC-1α activation and therefore regulates multiple pathways involved in cellular energy homeostasis. In the present study, we assessed the effects of L6 myotubes incubation with 0.5, 1, and 3 µM PQQ solution for 2 and 24 hr with respect to the cells' lipid metabolism. We demonstrated that PQQ significantly elevates PGC-1α content in a dose- and time-dependent manner with the highest efficiency for 0.5 and 1 µM. The level of free fatty acids was diminished (24 hr: -66%), while an increase in triacylglycerol (TAG) amount was most pronounced after 0.5 µM (2 hr: +93%, 24 hr: +139%) treatment. Ceramide (CER) content was elevated after 2 hr incubation with 0.5 µM and after prolonged exposure to all PQQ concentrations. The cells treated with PQQ for 2 hr exhibited decreased sphinganine (SFA) and sphinganine-1-phosphate (SFA1P) level, while 24 hr incubation resulted in an elevated sphingosine (SFO) amount. In summary, PGC-1α activation promotes TAG and CER synthesis.

Assessment of the Main Compounds of the Lipolytic System in Treadmill Running Rats: Different Response Patterns between the Right and Left Ventricle.

The aim of the present study was to investigate the time and intensity dependent effects of exercise on the heart components of the lipolytic complex. Wistar rats ran on a treadmill with the speed of 18 m/min for 30 min (M30) or 120 min (M120) or with the speed of 28 m/min for 30 min (F30). The mRNA and protein expressions of the compounds adipose triglyceride lipase (ATGL), comparative gene identification-58 (CGI-58), G0/G1 switch gene 2 (G0S2), hormone sensitive lipase (HSL) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) were examined by real-time PCR and Western blot, respectively. Lipid content of free fatty acids (FFA), diacylglycerols (DG) and triacylglycerols (TG) were estimated by gas liquid chromatography. We observed virtually no changes in the left ventricle lipid contents and only minor fluctuations in its ATGL mRNA levels. This was in contrast with its right counterpart i.e., the content of TG and DG decreased in response to both increased duration and intensity of a run. This occurred in tandem with increased mRNA expression for ATGL, CGI-58 and decreased expression of G0S2. It is concluded that exercise affects behavior of the components of the lipolytic system and the lipid content in the heart ventricles. However, changes observed in the left ventricle did not mirror those in the right one.

High-Fat Feeding in Time-Dependent Manner Affects Metabolic Routes Leading to Nervonic Acid Synthesis in NAFLD.

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation in the liver. The disturbances in the fatty acid composition of stored lipids are more important than the lipid species itself, which may influence the overall effect caused by these molecules. Thus, uncovering time-dependent changes in the fatty acid composition of accumulated lipid fractions after a high fat diet seems to be a new marker of NAFLD occurrence. The experiments were conducted on high fat fed Wistar rats. The blood and liver samples were collected at the end of each experimental week and used to assess the content of lipid fractions and their fatty acid composition by gas liquid chromatography. The expression of proteins from lipid metabolism pathways and of fatty acid exporting proteins were detected by Western blotting. In the same high fat feeding period, decreased de novo lipogenesis, increased ß-oxidation and lipid efflux were demonstrated. The observed effects may be the first liver protective mechanisms against lipotoxicity. Nevertheless, such effects were still not sufficient to prevent the liver from proinflammatory lipid accumulation. Moreover, the changes in liver metabolic pathways caused the plasma nervonic acid concentration in sphingomyelin to decrease simultaneously with NAFLD development, which may be a steatosis occurrence prognostic marker.

Fatty acids and sphingolipids profile in the blood plasma of experienced divers in response to hyperbaric exposure.

INTRODUCTION: Hyperbaric exposure mimics air-breathing scuba diving, which is reaching enormous popularity around the world. The diver's body is subjected to a broad range of divergent effects exerted by, e.g.: an increased partial pressure of inert gases, microclotting, oxidative stress and/or production of gas bubbles. However, very little is known regarding the impact of hyperbaric exposure on plasma fatty acids content and composition, together with the body's sphingolipids profile. MATERIAL AND METHODS: The aim of this study was to investigate the contents of major fatty acids present in the plasma as well as sphingolipids, namely: sphingosine (SPH); sphingosine-1-phosphate (S1P); sphinganine (SPA); and ceramide (CER), after hyperbaric exposure corresponding to dives conducted to the depths of 30 and 60 meters of seawater. For the plasma lipids measurements, high-performance liquid chromatography together with gas-liquid chromatography were applied. RESULTS: We demonstrated that hyperbaric exposure does not affect the content and composition of plasma fatty acids of experienced divers. Similarly, the amounts of major sphingolipids fractions were not influenced, as only the content of sphingosine-1-phosphate in the plasma was significantly decreased. CONCLUSIONS: Observed lack of significant changes in plasma lipid profile after hyperbaric exposure suggests that the procedure might be considered as secure. However, decreased sphingosine-1-phosphate content in the plasma might possibly exert some adverse effects.

Challenging of AS160/TBC1D4 Alters Intracellular Lipid milieu in L6 Myotubes Incubated With Palmitate.

The Akt substrate of 160 kDa (AS160) is a key regulator of GLUT4 translocation from intracellular depots to the plasma membrane in myocytes. Likely, AS160 also controls LCFAs transport, which requires relocation of fatty acid transporters. The aim of the present study was to determine the impact of AS160 knockdown on lipid milieu in L6 myotubes incubated with palmitate (PA). Therefore, we compared two different settings, namely: 1) AS160 knockdown prior to palmitate incubation (pre-PA-silencing, AS160- /PA); 2) palmitate incubation with subsequent AS160 knockdown (post-PA-silencing, PA/AS160- ). The efficiency of AS160 silencing was checked at mRNA and protein levels. The expression and localization of FA transporters were determined using Western Blot and immunofluorescence analyses. Intracellular lipid content (FFA, DAG, TAG, and PL) and FA composition were estimated by GLC, whereas basal palmitate uptake was analyzed by means of scintigraphy. Both groups with silenced AS160 were characterized by a greater expression of FA transporters (FAT/CD36, FATP-1, 4) which had contributed to an increased FA cellular influx. Accordingly, we observed that post-PA-silencing of AS160 resulted in a marked decrement in DAG, TAG, and PL contents, but increased FFA content (PA/AS160- vs. PA). The opposite effect was observed in the group with pre-PA-silencing of AS160 in which AS160 knockdown did not affect the lipid pools (AS160- /PA vs. PA). Our results indicate that post-PA-silencing of AS160 has a capacity to decrease the lipotoxic effect(s) of PA by decreasing the content of lipids (DAG and PL) that promote insulin resistance in myotubes. J. Cell. Physiol. 232: 2373-2386, 2017. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals Inc.

Sphingolipids metabolism in the salivary glands of rats with obesity and streptozotocin induced diabetes.

Diabetes is considered a major public health problem affecting millions of individuals worldwide. Remarkably, scientific reports regarding salivary glands sphingolipid metabolism in diabetes are virtually non-existent. This is odd given the well-established link between the both in other tissues (e.g., skeletal muscles, liver) and the key role of these glands in oral health preservation. The aim of this paper is to examine sphingolipids metabolism in the salivary glands in (pre)diabetes (evoked by high fat diet feeding or streptozotocin). Wistar rats were allocated into three groups: control, HFD-, or STZ-diabetes. The content of major sphingolipid classes in the parotid (PSG) and submandibular (SMSG) glands was assessed via chromatography. Additionally, Western blot analyses were employed for the evaluation of key sphingolipid signaling pathway enzyme levels. No changes in ceramide content in the PSG were found, whereas an increase in ceramide concentration for SMSG of the STZ group was observed. This was accompanied by an elevation in SPT1 level. Probably also sphingomyelin hydrolysis was increased in the SMSG of the STZ-diabetic rats, since we observed a significant drop in the amount of SM. PSG and SMSG respond differently to (pre)diabetes, with clearer pattern presented by the later gland. An activation of sphingomyelin signaling pathway was observed in the course of STZ-diabetes, that is, metabolic condition with rapid onset/progression. Whereas, chronic HFD lead to an inhibition of sphingomyelin signaling pathway in the salivary glands (manifested in an inhibition of ceramide de novo synthesis and accumulation of S1P).

Plasma Sphingolipids in Acute Pancreatitis.

Acute pancreatitis (AP) is a prevalent gastrointestinal disorder associated with systemic inflammatory response syndrome and, in the case of severe AP, a mortality rate ranging from 36% to 50%. Standard clinical treatment of AP includes intensive hydration, analgesia, and management of complications. Unfortunately, the direct treatment of AP at the level of its molecular pathomechanism has not yet been established. Recent studies indicate that the sphingolipid signaling pathway may be one of the important factors contributing to the development of inflammation in pancreatic diseases. In the current study, we sought to investigate this promising route. We examined the plasma sphingolipid profile of 44 patients with acute pancreatitis, dividing them into three groups: mild, moderate and severe AP. Samples were collected from these groups at days 1, 3 and 7 following their hospital admission. We demonstrated significant changes in blood plasma sphingolipids in relation to the time course of AP. We also found an inhibition of de novo ceramide synthesis in mild and moderate AP. However, the most important and novel finding was a significant elevation in sphingosine-1-phosphate (S1P) (a downstream metabolite of ceramide) in mild AP, as well as a dramatic reduction in the lipid molecule content in the early stage (days 1 and 3) of severe AP. This strongly indicates that plasma S1P could serve as a prognostic marker of AP severity.

The Effects of AS160 Modulation on Fatty Acid Transporters Expression and Lipid Profile in L6 Myotubes.

BACKGROUND/AIMS: AS160 is a key intracellular regulator of energy utilization in cells. It was shown to regulate GLUT4 translocation from intracellular depots to the plasma membrane, with subsequent changes in facilitated glucose uptake into the skeletal muscles. Similarly, also free fatty acids (FFAs) transmembrane transport seems to be largely protein-mediated. Therefore, the objective of this study was to examine the effects of moderate AS160 depletion (-82% mRNA, -25% of protein content) on the expression of fatty acid transporters and subsequent changes in lipid profile in L6 myotubes. RESULTS: Surprisingly, moderate down regulation of AS160 expression was followed by increased AS160 phosphorylation (∼40%). These resulted in a greater expression of fatty acid transporters, namely FABPpm and FAT/CD36, with subsequently increased FAs cellular influx. No changes in the expression of FATP1 and 4 were noticed. Accordingly, we have observed a reduction in total TAG content. This was mainly caused by a significant changes in TAG fatty acids composition favouring a decrease in the amount of palmitic and stearic fatty acid moieties. In contrast, our experimental intervention led to distinctively increased total content of DAG and PL, but concomitantly decreased the content of all measured sphingolipids, e.g. SFA, SA1P, CER, SFO and S1P, in the AS160 knockdown group. CONCLUSIONS: Modulation of AS160 level and activity led to significant increase in the concentration of DAG and PL, which was associated with changes in FAs composition and expression of fatty acid transporters. Interestingly, the intervention also simultaneously decreased the content of sphingolipids.

Effect of streptozotocin-induced diabetes on lipids metabolism in the salivary glands.

BACKGROUND: Diabetes is one of the most common metabolic diseases. Moreover, previous studies indicate that diabetes may cause changes in the salivary glands phenotype and in the composition of saliva itself. Therefore, the main objective of this study was to determine the effects of streptozotocin induced diabetes on lipid profile of the rat salivary glands. METHODS: Male Wistar rats were divided into two groups: control and STZ-induced diabetes. At the end of the experiment all animals were sacrificed and samples of the parotid and submandibular salivary glands were excised. Major lipid fractions concentrations were determined by means of chromatography (TLC and GC). RESULTS: We observed a significant increase (∼3.5 fold) in the level of triacylglycerol in both the parotid and submandibular salivary glands of diabetic rats. The abovementioned changes were accompanied by significant, although less dramatic (i.e. from -60% to -90%), decrements in the levels of other lipid classes (phospholipids, free fatty acids and diacylglycerol). CONCLUSIONS: In our study we have showed, presumably for the first time, that streptozotocin induced diabetes causes decrement in PH content with subsequent atrophy and malfunction in both parotid and submandibular salivary glands. Another novel finding of our research is that diabetic rats were characterized by an increased TG accumulation in both parotid and submandibular salivary glands. The later one could be a clinical manifestation of diabetes.

Modest decrease in PGC1α results in TAG accumulation but not in insulin resistance in L6 myotubes.

BACKGROUND/AIMS: PGC-1α is an important cellular protein (coactivator) regulating myocyte mitochondria number and function, and therefore whole cellular energy status. The aim of this work was to investigate the effects of modest, temporary PGC-1α knock-down on L6 myotubes insulin resistance in a light of cellular lipid metabolism. METHODS: Gas liquid chromatography was applied for assessing FAs content and composition. For the expression of mitochondrial enzymes, as well as FA and glucose transporters, Western Blot technique was adopted. Additionally, radiolabelled glucose and palmitic acid uptake was performed to estimate the nutrients cellular influx. RESULTS: Modest (-24%) PGC-1α protein ablation resulted in decreased mitochondrial activity in general (reduced Cyt C content) and FAs oxidation in particular (diminished ß-HAD expression) without increased FAs cellular influx. The aforementioned intervention led to significantly increased TAG cellular level, but not DAG nor CER. Consequently, no changes in cellular insulin responsiveness were noticed. CONCLUSIONS: Modest (-24%) PGC-1α protein depletion results in lipid accumulation, without causing insulin resistance. Importantly, it seems that this TAG loading is a result of decreased mitochondrial oxidative capacity and/or possibly increased lipid biosynthesis but not fatty acid cellular influx.

The Role of PGC-1α in the Development of Insulin Resistance in Skeletal Muscle - Revisited.

Currently, obesity is a predominant medical condition and an important risk factor for the development of several diseases, including type 2 diabetes mellitus. Importantly, most research has indicated lipid-induced insulin resistance in skeletal muscles is a key link between the aforementioned pathological conditions. PGC-1α is a prominent regulator of myocellular energy metabolism orchestrating gene transcription programming in response to numerous environmental stimuli. Moreover, it is widely acknowledged that mitochondrial metabolism (primary metabolic target of PGC-1α) disturbances are widely acknowledged contributors to type 2 diabetes development. Therefore, it seems surprising that the exact physiological contribution of PGC-1α in the development of insulin resistance in skeletal muscle remains poorly understood. This review aims to reconcile these allegedly different findings by looking for a common denominator in the role(s) of PGC-1α in respect to lipid-induced insulin resistance in skeletal muscle. Our scrutiny of the literature indicates that interventions at the level of PGC-1α may exert beneficial effects on myocytes in respect to lipid-induced insulin resistance. The latter takes place as a result of a positive net energy balance (fatty acids oxidation surpassing their accumulation rate). Moreover, the aforementioned effects may not necessarily be limited to physically active states. They seem to occur, however, only within a physiologically observed range in muscle cells (approximately 1-fold changes in PGC-1α protein expression).

Hyperthyroidism evokes myocardial ceramide accumulation.

BACKGROUND: Thyroid hormones (THs) are key regulators of cardiac physiology as well as modulators of different cellular signals including the sphingomyelin/ceramide pathway. The objective of this study was to examine the effect of hyperthyroidism on the metabolism of sphingolipids in the muscle heart. METHODS: Male Wistar rats were treated for 10 days with triiodothyronine (T3) at a dose of 50µg/100g of body weight. Animals were then anaesthetized and samples of the left ventricle were excised. RESULTS: We have demonstrated that prolonged, in vivo, T3 treatment increased the content of sphinganine (SFA), sphingosine (SFO), ceramide (CER) and sphingomyelin (SM), but decreased the level of sphingosine-1-phosphate (S1P) in cardiac muscle. Accordingly, the changes in sphingolipids content were accompanied by a lesser activity of neutral sphingomyelinase and without significant changes in ceramidases activity. Hyperthyroidism also induced activation of AMP-activated protein kinase (AMPK) with subsequently increased expression of mitochondrial proteins: cytochrome c oxidase IV (COX IV), ß-hydroxyacyl-CoA dehydrogenase (ß-HAD), carnityne palmitoyltransferase I (CPT I) and nuclear peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α). CONCLUSIONS: We conclude that prolonged T3 treatment increases sphingolipids metabolism which is reflected by higher concentration of SFA and CER in heart muscle. Furthermore, hyperthyroidism-induced increase in heart sphingomyelin (SM) concentration might be one of the mechanisms underlying maintenance of CER at relatively low level by its conversion to SM together with decreased S1P content.

Inhibition of ceramide de novo synthesis reduces liver lipid accumulation in rats with nonalcoholic fatty liver disease.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is an insulin resistance-related hepatic disorder which can transform to cirrhosis. Insulin resistance deregulates hepatic lipid metabolism, leading to accumulation of cytotoxic lipids including ceramide and diacylglycerols. Myriocin, obtained from fungi traditionally used in Chinese medicine in an effort to attain eternal youth, is a potent pharmacological inhibitor of ceramide de novo synthesis. We examined whether inhibition of ceramide de novo synthesis with myriocin ameliorate hepatic lipid accumulation and reverse NAFLD. METHODS: The experiment was carried out on male Wistar rats. The animals were divided into four groups: (i) control group, fed standard rodent diet, (ii) group, fed standard diet also treated with myriocin for 7 days, (iii) group, fed high-fat diet for 5 weeks, (iv) group, fed high-fat diet and treated with myriocin. In liver samples sphingolipids: ceramide, sphingosine and sphingosine-1-phosphatate and neutral lipids, such as diacylglycerols and triacylglycerols were measured. In peripheral blood samples, glucose and insulin levels and aminotransferases activities were measured. RESULTS: High-fat diet feeding caused NAFLD, confirmed by histological assessment, with increased hepatic lipids accumulation and whole-body insulin resistance. After treating with inhibitor of ceramide de novo synthesis, decrease in hepatic ceramide and other toxic lipids were noticed. Moreover, histological analysis of liver samples revealed that inhibition of ceramide de novo synthesis reduced hepatic steatosis. CONCLUSIONS: Inhibition of ceramide de novo synthesis reduced hepatic lipid accumulation in rats with NAFLD, this led to amelioration of hepatic steatosis.

Adipose tissue place of origin and obesity influence sphingolipid signaling pathway in the adipocytes differentiated from ADMSCs isolated from morbidly obese women.

Adipose derived mesenchymal stem cells (ADMSCs) are a component of adipose tissue that in recent years has gained on importance. The progenitor cells serve as an essentially unlimited source of new adipocytes and therefore are considered to be an important determinant of the tissue's physiology. In this paper we investigated mature adipocytes differentiated from ADMSCs obtained from subcutaneous/visceral fat of patients with different metabolic status (lean, obese without and with metabolic syndrome). We focused our interests on the sphingolipid signaling pathway, i.e.a signal transduction system indispensable for cells functioning, but also implicated in the development of medical conditions associated with obesity. We observed that the cells derived from visceral tissue had significantly greater levels of almost all the examined sphingolipids (especially Cer, dhCer, SM). Moreover, obesity and metabolic syndrome present in donor patients was associated with an increased level of sphingosine kinase (SPHK) and the product of its reaction sphingosine-1-phosphate (S1P). Moreover, the condition appeared to display a tissue specific pattern. Namely, the adipocytes of subcutaneous provenance had an increased activation of ceramide de novo synthesis pathway when the donors of ADMSCs had metabolic syndrome. The above translated into greater accumulation of ceramide in the cells. To our knowledge this is the first study that demonstrated altered sphingolipid profile in the mature adipocytes differentiated from ADMSCs with respect to the stem cells tissue of origin and the donor patient metabolic status.

[The role of sphingolipids in selected cardiovascular diseases]. / Rola sfingolipidów w wybranych chorobach ukladu krazenia.

Bioactive sphingolipids are engaged with numerous cellular processes such as cell differentiation, proliferation and apoptosis. Sphingolipid metabolism in heart is regulated by physical exercise and PPARs. Ceramide, the main second messenger of sphingomyelin pathway of signal transduction, was found to be involved in development of cardiac dysfunction after ischemia/reperfusion. On the other hand ceramide derivative sphingosine- 1- phosphate has been shown to exert potent cardioprotective action and guards cardiomyocytes against ischemic/reperfusion injury. Pharmacological compounds, which regulate metabolism of sphingolipids can be potentially useful in treatment of selected cardiovascular diseases. The aim of this work is critical review of physiological and pathological role of sphingolipids in circulatory system.