Shotgun Lipidomic Analysis for Differentiation of Niche Cold Pressed Oils.

The fast-growing food industry is bringing significant number of new products to the market. To protect consumers' health and rights, it is crucial that food control laboratories are able to ensure reliable quality testing, including product authentication and detection of adulterations. In our study, we applied a fast and eco-friendly method based on shotgun-lipidomic mass spectrometry for the authentication of niche edible oils. Comprehensive lipid profiles of camelina (CA), flax (FL) and hemp (HP) seed oils were obtained. With the aid of principal component analysis (PCA), it was possible to detect and distinguish each of them based on their lipid profiles. Lipidomic markers characteristic ofthe oils were also identified, which can be used as targets and expedite development of new multiplexed testing methods.

Blackcurrant (Ribes nigrum L.) Seeds-A Valuable Byproduct for Further Processing.

The rational exploitation of byproducts is important from the point of view of their potential applicability in various fields. In this study, the possibility of further processing of blackcurrant seeds (BCs), which are a byproduct of fruit processing, was investigated. BCs were used as a material for the extraction of oil on a semi-industrial scale, and the residues were assessed in terms of their potential application in skin care products. Supercritical fluid extraction (SFE) using CO2 at pressures of 230 and 330 bar and extraction temperature of 40 °C was exploited for isolation of oil, and the products were characterised taking into account lipophilic constituents. After 120 min, the oil yields were 19.67% and 20.94% using CO2 at 230 and 330 bar, respectively, which showed that SFE was an effective method on a semi-industrial scale, taking into account the extraction yield. The oils had similar fatty acid compositions with a high percentage of linoleic acid (ca. 43%); however, tocopherols and carotenoids were most abundant in the oil obtained at 230 bar. It was also found that the composition of the SFE oils was comparable with that of cold-pressed oil, which shows that supercritical fluid extraction provides a high-quality product; therefore, it can be an alternative to cold pressing. Furthermore, the chemical compositions of the extracts from the oil isolation residues were established using UPLC-MS, and the impact of the extracts on human skin fibroblasts was assessed using the MTT and NR assays. The quantitative analysis revealed that the residues contained high amounts of polyphenolic acids, including gallic, protocatechuic, and hydroxybenzoic acid derivatives, as well as flavonoids, especially quercetin and kaempferol glucoside. Moreover, it was found that the extracts were nontoxic and exerted a stimulatory effect on cell metabolism. Therefore, they can be a valuable additive to natural plant-based cosmetics. Our results showed that blackcurrant seeds, regarded as a byproduct, can be a valuable material for further use.

Metabolic Effects of Metformin in the Failing Heart.

Accumulating evidence shows that metformin is an insulin-sensitizing antidiabetic drug widely used in the treatment of type 2 diabetes mellitus (T2DM), which can exert favorable effects on cardiovascular risk and may be safely used in patients with heart failure (HF), and even able to reduce the incidence of HF and to reduce HF mortality. In failing hearts, metformin improves myocardial energy metabolic status through the activation of AMP (adenosine monophosphate)-activated protein kinase (AMPK) and the regulation of lipid and glucose metabolism. By increasing nitric oxide (NO) bioavailability, limiting interstitial fibrosis, reducing the deposition of advanced glycation end-products (AGEs), and inhibiting myocardial cell apoptosis metformin reduces cardiac remodeling and hypertrophy, and thereby preserves left ventricular systolic and diastolic functions. While a lot of preclinical and clinical studies showed the cardiovascular safety of metformin therapy in diabetic patients and HF, to confirm observed benefits, the specific large-scale trials configured for HF development in diabetic patients as a primary endpoints are necessary.

The pathophysiological basis of the protective effects of metformin in heart failure.

Metformin, currently recommended as the drug of first choice in type 2 diabetes mellitus (T2DM), is one of the few antihiperglycemic drugs to reduce cardiovascular risk. Nonetheless, due to the risk of lactic acidosis during metformin therapy, its usage in patients with diabetes and heart failure (HF) is still a matter of debate. The aim of this review is to present data supporting the possibility of using metformin in the treatment of diabetic patients with concomitant heart failure. In the failing heart, metformin through the mechanism related to AMP-activated protein kinase (AMPK) activity, improves free fatty acids (FFA) and glucose metabolism, mitochondrial biogenesis, as well as nitric oxide (NO)-NO synthase pathway. Metformin can also inhibit the generation and accumulation of advanced glycation end products (AGEs) and thereby prevents the development of the adverse structural and functional changes in myocardium.In summary, experimental and clinical data indicate the ability of metformin to prevent the development of the structural and functional changes in myocardium, although further basic research and clinical studies assessing benefits and safety of metformin therapy in patients with HF are required.

Differential effects of statins on endogenous H2S formation in perivascular adipose tissue.

Hydrogen sulfide (H(2)S) is a new gasotransmitter synthesized enzymatically from l-cysteine in cytosol and is oxidized in mitochondria. In the cardiovascular system, H(2)S regulates vascular tone, inhibits atherogenesis, and protects against myocardial ischemia-reperfusion injury. We examined the effect of statins on vascular H(2)S production. Male Wistar rats received pravastatin (40mg/kg/day) or atorvastatin (20mg/kg/day) for 3 weeks and then H(2)S formation was measured in aortic media, periaortic adipose tissue (PAAT) and the liver. Only atorvastatin increased H(2)S production in PAAT whereas both statins stimulated its formation in the liver. Neither statin affected H(2)S production in aortic media. H(2)S formation in post-mitochondrial supernatant was higher than in mitochondria-containing supernatant and was not influenced by statins in any tissue. In addition, oxidation of exogenous H(2)S in isolated liver mitochondria was slower in statin-treated than in control rats. These data indicate that statins increase net H(2)S production by inhibiting its mitochondrial oxidation. Statins had no effect on the activity of H(2)S-metabolizing enzyme, sulfide:quinone oxidoreductase, measured at saturating coenzyme Q concentration. Both statins reduced CoQ(9) concentration in plasma and liver, but only atorvastatin decreased CoQ(9) in PAAT. Atorvastatin attenuated phenylephrine-induced contraction of PAAT+ but not of PAAT- aortic rings. Effects of atorvastatin on net H(2)S production, mitochondrial H(2)S oxidation and aortic contractility were abolished by supplementation of exogenous CoQ(9). In conclusion, lipophilic atorvastatin, but not hydrophilic pravastatin, increases net H(2)S production in perivascular adipose tissue by inhibiting its mitochondrial oxidation. This effect is mediated by statin-induced CoQ(9) deficiency and results in the augmentation of anticontractile effect of perivascular adipose tissue.

Relation between markers of inflammation and estradiol in older men.

BACKGROUND: Inflammation plays a key role in the development of atherosclerosis. Studies in women receiving estrogens show their proinflammatory effects. This study sought to determine relation between sex hormones and 2 inflammation markers: C-reactive protein and fibrinogen. MATERIAL/METHODS: One hundred men of at least age 50 years were enrolled in the study. Plasma levels of total testosterone, estradiol, sex hormone binding globulin, high-sensitivity C-reactive protein, and fibrinogen were measured. Free estradiol and free testosterone were calculated. RESULTS: Estradiol and free estradiol levels were positively correlated with C-reactive protein and fibrinogen. In a subgroup analysis, this association persisted only in patients with stable coronary artery disease. No significant correlations were found between testosterone, free testosterone, sex hormone binding globulin, and markers of inflammation. CONCLUSIONS: This study suggests that estradiol may have proinflammatory effects in older men with coronary artery disease.

Prospective evaluation of the outcome of velopharyngeal insufficiency therapy after simultaneous double z-plasty and sphincter pharyngoplasty.

OBJECTIVE: One of the main goals in the management of cleft palate is to achieve a good quality of speech. The aim of the prospective study was to evaluate the effectiveness of therapy in patients with velopharyngeal insufficiency treated by simultaneously performed Furlow and Orticochea operations. PATIENTS AND METHODS: From May 2007 to May 2008 we treated 14 consecutive patients (6 males and 8 females, mean age 14 years). The indications for surgery were based on nasofiberscopic examination, evaluation of speech quality, nasometry and morphology of the palate. The velopharyngeal closure was below 80% in all the patients; they had pronounced nasality and limited intelligibility of speech. All the palates were short. RESULTS: The final outcome of treatment was based on the combined evaluation of 4 parameters: closure, speech intelligibility, nasality and the nasalance index. Ten patients achieved full recovery (71%), the remaining 4 had improved recovery (29%). CONCLUSION: A 1-stage Furlow operation and sphincter pharyngoplasty are an effective modality in the therapy of velopharyngeal insufficiency. Indications for posterior pharyngeal flap pharyngoplasty should be limited to the cases in which a simultaneous Furlow operation and sphincter pharyngoplasty are not possible due to a deficit of the palatine tissue.

Paraoxonase 1 Phenotype and Protein N-Homocysteinylation in Patients with Rheumatoid Arthritis: Implications for Cardiovascular Disease.

Paraoxonase 1 (PON1) is the high density lipoprotein-associated esterase which inhibits the development of atherosclerosis by metabolizing lipid peroxidation products as well as hydrolyzing proatherogenic metabolite of homocysteine (Hcy), Hcy thiolactone, which otherwise reacts with lysine groups of proteins, thus forming N-Hcy-protein in a process referred to as protein N-homocysteinylation. Rheumatoid arthritis (RA) is the chronic inflammatory autoimmune disease associated with increased risk of cardiovascular complications, but the underlying mechanisms are incompletely understood. We examined PON1 status and N-homocysteinylation of serum proteins in patients with RA. Blood was collected from 74 RA patients and 70 control subjects. PON1 activity was measured toward synthetic (paraoxon, phenyl acetate) and natural (Hcy thiolactone) substrates. PON1 protein concentration was measured by ELISA. Total Hcy as well as N-Hcy-protein were measured in serum as well. PON1 activity toward Hcy thiolactone was lower in RA patients than in control subjects which was accompanied by increased concentration of N-Hcy-protein despite normal total Hcy concentration. PON1 protein concentration was unchanged in the RA group, but the specific enzyme activity was reduced. When RA patients were categorized according to the DAS28-ESR score, PON1 concentration and enzymatic activity were lower whereas N-Hcy-protein was higher in those with high disease activity. PON1 activity and Hcy thiolactone were correlated with DAS28-ESR score and myeloperoxidase concentration. In conclusion, RA is associated with deficiency of PON1 activity and increased protein N-homocyseinylation which may contribute to accelerated development of cardiovascular diseases.

Cladribine Treatment Improved Homocysteine Metabolism and Increased Total Serum Antioxidant Activity in Secondary Progressive Multiple Sclerosis Patients.

Hyperhomocysteinemia plays a crucial role in the pathogenesis of many diseases of the central nervous system (CNS). The nervous system is particularly sensitive to high homocysteine (Hcy) level mainly due to its prooxidative and cytotoxic effects. Cladribine, a drug recently registered for the treatment of multiple sclerosis (MS), possesses additionally neuroprotective effects which are independent of its peripheral immunosuppressant action. Accumulating evidence suggests that oxidative stress and homocysteine thiolactone-mediated protein homocysteinylation play a causal role in MS. Both of these processes may be attenuated by paraoxonase 1 (PON1). Therefore, in the present study, we aimed to examine whether the beneficial effects of the drug in MS patients with a secondary progressive (SP) clinical course, treated with cladribine subcutaneously (s.c.), may be related to its ability to modify serum PON1 activity, Hcy concentration, and protein homocysteinylation, as well as to correct total antioxidant status. A total of 118 subjects were enrolled into the study: (1) patients with a SP type of MS, SP-MS (n = 40); (2) patients with a relapsing-remitting (RR) type of MS, RR-MS (n = 30); and (3) healthy people (n = 48). Patients with SP-MS were treated with cladribine. The drug was given in SP-SM patients s.c. six times every 6 weeks up to a total mean cumulative dose of 1.8 mg/kg. PON1 activity was assessed spectrophotometrically. The level of Hcy, homocysteine thiolactone (HTL) attached to plasma proteins (N-Hcy-protein), and antibodies against homocysteinylated proteins was assessed with an enzyme immunoassay. The total antioxidant activity of the serum was assessed with the ferric-reducing activity of plasma (FRAP) method. Basically, there was no difference in PON1 activity between untreated SP-MS, RR-MS, and control subjects. Serum Hcy was significantly higher in RR-MS patients (p < 0.001) and in SP-MS patients (p < 0.01) compared to the control group. The N-Hcy protein level was higher in RR-MS patients (p < 0.05) in comparison to the control group. Moreover, the elevated level of antibodies against homocysteinylated proteins was observed in the serum of patients with SP-MS. The total antioxidant capacity of serum was lower in MS patients vs. the control group (p < 0.001). After cladribine treatment, the activity of PON1 did not change in SP-MS patients, whereas cladribine treatment decreased the level of total Hcy (p < 0.05). Treatment with cladribine increased the total serum antioxidant activity in SP-MS patients (p < 0.01). The Expanded Disability Status Scale (EDSS) score did not change in SP-MS patients. Cladribine treatment in the SP-MS group attenuates hyperhomocysteinemia-induced protein homocysteinylation (n.s.). It also stabilises the neurological condition of SP-MS patients. The stabilisation of a neurological condition observed in SP-MS patients after cladribine treatment may be partially related to its ability to reduce elevated Hcy level and to improve serum antioxidant potential.

The effect of exenatide (a GLP-1 analog) and sitagliptin (a DPP-4 inhibitor) on plasma platelet-activating factor acetylhydrolase (PAF-AH) activity and concentration in normal and fructose-fed rats.

Inflammation and oxidative stress are the two processes crucial in atherogenesis. Platelet-activating factor acetylhydrolase (PAF-AH), a plasma lipoprotein-associated enzyme, degrades pro-inflammatory lipids generated within oxidatively modified lipoproteins. Extensive evidence shows that incretin-based drugs, a new class of anti-diabetic agents, can provide cardiovascular protection that cannot be attributed to their glucose-lowering effects. The present study was undertaken to determine whether the antiatherogenic effects of the GLP-1(glucagon-like peptide-1) receptor agonist (exenatide) and DPP-4(dipeptidyl peptidase-4) inhibitors (sitagliptin) may occur via the regulation of platelet-activating factor acetylhydrolase (PAF-AH) activity/mass and inhibition of low-density lipoprotein (LDL) oxidation in the fructose-fed rats. Normal and fructose-fed rats (8 wk) were treated (4 wk) with sitagliptin (5 and 10 mg/kg p.o.) or with exenatide (5 and 10 µg/kg, s.c.). Plasma PAF-AH activity and phosphatidylcholine (PC) concentration were measured colorimetrically. Plasma PAF-AH concentration, oxidized LDL (oxLDL), hexanoyl-Lys adduct (HEL), lyso-PC, apolipoprotein A-I (apoA-I), apoB, platelet-activating factor (PAF), monocyte chemoattractant protein-1 (MCP-1) and endothelin-1 (ET-1) were measured by ELISA. The four-week exenatide (5 µg/kg, sc.) treatment of fructose fed-rats significantly increased plasma PAF-AH activity (+33%, P < 0.001) and decreased the level of circulating oxLDL (-42%, P < 0.05) and MCP-1 (-23%, P < 0.01). These changes were accompanied by the decrease in plasma PC/lyso-PC (-47%, P < 0.001) and apoB/apoA-I ratio (-75%, P < 0.001). The effect of exenatide on enzyme activity was associated with only a minor effect on metabolic parameters and was independent of weight reduction. Exenatide but not sitagliptin inhibits oxidative modification of LDL probably due to favorable effect on plasma PAF-AH activity.

Renal antioxidant enzymes and glutathione redox status in leptin-induced hypertension.

Previously, we have demonstrated that leptin increases blood pressure (BP) in the rats through two oxidative stress-dependent mechanisms: stimulation of extracellular signal-regulated kinases (ERK) by H(2)O(2) and scavenging of nitric oxide (NO) by superoxide (O(2-.)). Herein, we examined if renal glutathione system and antioxidant enzymes determine the mechanism of prohypertensive effect of leptin. Leptin administered at 0.5 mg/kg/day for 4 or 8 days increased BP and renal Na(+),K(+)-ATPase activity and reduced fractional sodium excretion; these effects were prevented by NADPH oxidase inhibitor, apocynin. Superoxide scavenger, tempol, abolished the effect of leptin on BP and renal Na(+) pump in rats receiving leptin for 8 days, whereas ERK inhibitor, PD98059, was effective in animals treated with leptin for 4 days. Leptin administered for 4 days decreased glutathione (GSH) and increased glutathione disulfide (GSSG) in the kidney. In animals receiving leptin for 8 days GSH returned to normal level, which was accompanied by up-regulation of gamma-glutamylcysteine synthetase (gamma-GCS), a rate-limiting enzyme of the GSH biosynthetic pathway. In addition, superoxide dismutase (SOD) activity was decreased, whereas glutathione peroxidase (GPx) was increased in rats receiving leptin for 8 days. Cotreatment with gamma-GCS inhibitor, buthionine sulfoximine (BSO), accelerated, whereas GSH precursor, N-acetylcysteine (NAC), attenuated leptin-induced changes in gamma-GCS, SOD, and GPx. In addition, coadministration of BSO changed the mechanism of BP elevation from H(2)O(2)-ERK to (O(2-.))-NO dependent in animals receiving leptin for 4 days, whereas NAC had the opposite effect in rats treated with leptin for 8 days. These results suggest that initial change in GSH redox status induces decrease in SOD/GPx ratio, which results in greater amount of (O)2-.)) versus H(2)O(2) in later phase of leptin treatment, thus shifting the mechanism of BP elevation from H(2)O(2)-ERK to (O(2-.))-NO dependent.

Role of extracellular signal-regulated kinases (ERK) in leptin-induced hypertension.

We investigated if extracellular signal-regulated kinases (ERK) and oxidative stress are involved in the pathogenesis of arterial hypertension induced by chronic leptin administration in the rat. Leptin was administered at a dose of 0.25 mg/kg twice daily s.c. for 4 or 8 days. Blood pressure (BP) was higher in leptin-treated than in control animals from the third day of the experiment. The superoxide dismutase (SOD) mimetic, tempol, normalized BP in leptin-treated rats on days 6, 7 and 8, whereas the ERK inhibitor, PD98059, exerted a hypotensive effect on days 3 through 6. Leptin increased ERK phosphorylation level in renal and aortic tissues more markedly after 4 than after 8 days of treatment. In addition, leptin reduced urinary Na(+) excretion and increased renal Na(+),K(+)-ATPase activity, and these effects were abolished on days 4 and 8 by PD98059 and tempol, respectively. The levels of NO metabolites and cGMP were reduced in animals receiving leptin for 8 days. Markers of oxidative stress (H(2)O(2) and lipid peroxidation products) were elevated to a greater extent after 4 than after 8 days of leptin treatment. In contrast, nitrotyrosine, a marker of protein nitration by peroxynitrite, was higher in animals receiving leptin for 8 days. NADPH oxidase inhibitor, apocynin, prevented leptin's effect on BP, ERK, Na(+),K(+)-ATPase/Na(+) excretion and NO formation at all time points. SOD activity was reduced, whereas glutathione peroxidase (GPx) activity was increased in the group treated with leptin for 8 days. These data indicate that: (1) ERK, activated by oxidative stress, is involved only in the early phase of leptin-induced BP elevation, (2) the later phase of leptin-induced hypertension is characterized by excessive NO inactivation by superoxide, (3) the time-dependent shift from ERK to O(2)(-)-NO dependent mechanism may be associated with reduced SOD/GPx ratio, which favors formation of O(2)(-) instead of H(2)O(2).

Hydrogen sulfide in the regulation of insulin secretion and insulin sensitivity: Implications for the pathogenesis and treatment of diabetes mellitus.

Insulin secretion and sensitivity play an essential role in maintaining normal glucose level and their abnormalities result in diabetes mellitus. H2S-synthesizing enzymes, CBS and/or CSE, are expressed in insulin-secreting pancreatic ß cells and H2S inhibits insulin secretion by activating ATP-sensitive K+ channels. In addition, H2S has been reported to have either pro- or antiapoptotic effects on ß cells. Studies in the animal models suggest that excess of H2S in pancreatic islets may contribute to both type 1 and type 2 diabetes. H2S has also been demonstrated to regulate insulin sensitivity. In the liver, H2S stimulates gluconeogenesis and glycogenolysis and inhibits glucose utilization and glycogen storage. Its effect on insulin-stimulated glucose uptake in the adipose tissue is controversial; both stimulation and inhibition have been reported. H2S may also regulate adipose tissue lipolysis, adipokine production and inflammation; the processes important for local and systemic insulin sensitivity. Little is known about the effect of H2S on skeletal muscle metabolism. High fat diet, obesity and insulin resistance affect CBS/CSE/H2S system in the liver and adipose tissue, although the effect depends on diet composition, animals species and time of high-fat feeding. Most studies indicate that blood H2S concentration decreases in animal models of diabetes and in diabetic humans.

Role of PI3K and PKB/Akt in acute natriuretic and NO-mimetic effects of leptin.

Apart from controlling energy balance, leptin, a peptide hormone secreted by white adipose tissue, is also involved in the regulation of cardiovascular function. Previous studies have documented that leptin stimulates natriuresis and nitric oxide (NO) production, but the mechanism of these effects is incompletely elucidated. We examined whether phosphoinositide 3-kinase (PI3K) and its downstream effector, protein kinase B/Akt are involved in acute natriuretic and NO-mimetic effects of leptin in anaesthetized rats. Leptin (1 mg/kg i.v.) induced a marked increase in natriuresis and this effect was abolished by pretreatment with either wortmannin (15 microg/kg) or LY294002 (0.6 mg/kg), two structurally different PI3K inhibitors. Moreover, leptin increased plasma concentration and urinary excretion of NO metabolites, nitrites+nitrates (NO(x)), and of NO second messenger, cyclic GMP. In addition, leptin increased NO(x) and cGMP in aortic tissue. The stimulatory effect of leptin on NO(x) and cGMP was prevented by PKB/Akt inhibitor, triciribine, but not by either wortmannin or LY294002. Triciribine had no effect on leptin-induced natriuresis. Leptin stimulated Akt phosphorylation at Ser(473) in aortic tissue but not in the kidney. These results suggest that leptin-induced natriuresis is mediated by PI3K but not Akt, whereas NO-mimetic effect of leptin results from PI3K-independent stimulation of Akt.

Liver X receptors (LXRs). Part I: structure, function, regulation of activity, and role in lipid metabolism.

Liver X receptors (LXRs) alpha and ss belong to a family of nuclear receptors which form heterodimers with the retinoid X receptor and, upon ligand binding, stimulate the expression of target genes. LXRs were initially described as orphan receptors and oxidized cholesterol derivatives (oxysterols) were later identified as their natural ligands. In addition, several synthetic LXR agonists such as T0901317 and GW3965 were synthesized. Oxysterols are formed in amounts proportional to cholesterol content in the cell and therefore the LXRs operate as cholesterol sensors which protect from cholesterol overload by: 1) inhibiting intestinal cholesterol absorption, 2) stimulating cholesterol efflux from cells to high-density lipoproteins through the ATP-binding cassette transporters ABCA1 and ABCG1, 3) activating the conversion of cholesterol to bile acids in the liver, and (4) activating biliary cholesterol and bile acid excretion. In addition, LXR agonists activate de novo fatty acid synthesis by stimulating the expression of a lipogenic transcription factor, sterol regulatory element-binding protein-1c (SREBP-1c), leading to the elevation of plasma triglycerides and liver steatosis. Here we describe the structure and function of the LXRs, their endo- and exogenous agonists and antagonists, the regulation of LXR expression and activity, and their role in the regulation of cholesterol and lipid metabolism. In the accompanying article we characterize other effects of LXRs, alterations in LXR expression, and changes in the level of their endogenous agonists in pathological conditions as well as therapeutic implications.

Liver X receptors (LXRs). Part II: non-lipid effects, role in pathology, and therapeutic implications.

Liver X receptors (LXRs) alpha and ss belong to a group of nuclear receptors which, after ligand binding, regulate gene transcription. Their natural agonists are oxidized cholesterol derivatives (oxysterols). The main function of LX receptors is the regulation of cholesterol metabolism. In the first part of this work we discussed the structure and mechanism of action of LXRs, their agonists and antagonists, the regulation of LXR expression, and their role in cholesterol and lipid metabolism. In the present article we describe other roles of LXRs. Agonists of these receptors increase insulin sensitivity and stimulate insulin secretion. Activation of LXRs inhibits inflammation and autoimmune reactions. Moreover, pharmacological studies and genetic manipulations indicate that these receptors inhibit atherogenesis. LX receptors are also involved in the regulation of renin secretion, inhibit the formation of amyloid ss in the central nervous system, regulate gonadal function and steroidogenesis both in gonads and in adrenals, influence the proliferation and differentiation of keratinocytes, and inhibit the proliferation of tumor cells. Changes in the expression of these receptors and in the level of their agonists are observed in many diseases. Taking into account the multiple roles of LX receptors, their agonists may be applied in the future in the treatment of many disorders, including diabetes, inflammatory diseases, atherosclerosis, Alzheimer's disease, and hypogonadism. However, possible side effects should be taken into account, including enhancement of lipogenesis, hypertriglyceridemia, and liver steatosis. The function of LX receptors is also modulated by many currently used drugs such as statins, fibrates, and thazolidinedione derivatives.

[Late phoniatric results of treatment of patients with cleft palate operated on by one surgeon]. / Pózne foniatryczne wyniki leczenia chorych z rozszczepami podniebienia operowanych przez jednego chirurga.

INTRODUCTION: The aim of the study was the assessment of the late speech results the cleft palate patients. MATERIAL AND METHODIC. From January 1987 to December 1996 the first author performed 268 cleft palate surgeries. Of this number, 190 were complete unilateral and bilateral clefts, while 78 were operations of isolated soft palate. All the patients were consulted by a phoniatrist and a plastic surgeon. Among others, articulation, nasality, speech intelligibility were evaluated and nasometirc investigations were performed. The follow up examination involved 133 patients, 56 females and 77 males aged from 9 to 19 years (mean at the age of 13)--61 patients with unilateral cleft lip, alveolar process and palate (UCLP), 30 with bilateral clefts (BCLP) and 42 with isolated soft palate clefts (ICP). All the patients were operated on between 20 and 36 months of age (mean at 28 months). Two patients (1.5%) developed dehiscence of the wound on the palate and further two (1.5%) developed fistulae localized behind the alveolar process at a later time. All children with clefts were operated on by classical methods with the use of mucoperiosteal flaps for complete clefts according to Veauís method and soft palate clefts--Kilner-Wardill's method. RESULTS: Very good and good results of treatment were observed in 92% of cases. Poor outcome of treatment--excessive nasality or poor speech quality was observed in 11 patients (8%). A similar evaluation of the outcome of treatment was obtained on the basis of questionnaires sent to patients. CONCLUSIONS: It seems that good speech quality can be achieved despite relatively late palate repair using Veau and Kilner-Wardill methods.

H2O2 and Src-dependent transactivation of the EGF receptor mediates the stimulatory effect of leptin on renal ERK and Na+, K+-ATPase.

We examined the mechanism through which leptin increases Na(+), K(+)-ATPase activity in the rat kidney. Leptin was infused under anaesthesia into the abdominal aorta proximally to the renal arteries and then Na(+), K(+)-ATPase activity was measured in the renal cortex and medulla. Leptin (1mug/kgmin) increased Na(+), K(+)-ATPase activity after 3h of infusion, which was accompanied by the increase in urinary H(2)O(2) excretion and phosphorylation level of extracellular signal regulated kinase (ERK). The effect of leptin on ERK and Na(+), K(+)-ATPase was abolished by catalase, specific inhibitors of epidermal growth factor (EGF) receptor, AG1478 and PD158780, as well as by ERK inhibitor, PD98059, and was mimicked by both exogenous H(2)O(2) and EGF. The effect of leptin was also prevented by the inhibitor of Src tyrosine kinase, PP2. Leptin and H(2)O(2) increased Src phosphorylation at Tyr(418). We conclude that leptin-induced stimulation of renal Na(+), K(+)-ATPase involves H(2)O(2) generation, Src kinase, transactivation of the EGF receptor, and stimulation of ERK.

Role of nitric oxide and endothelium-derived hyperpolarizing factor (EDHF) in the regulation of blood pressure by leptin in lean and obese rats.

We investigated the role of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) in hemodynamic action of leptin. The effect of leptin (1 mg/kg i.p.) on systolic blood pressure (SBP) was examined in lean rats and in rats made obese by feeding highly palatable diet for either 1 or 3 months. Separate groups received NO synthase inhibitor, L-NAME, or EDHF inhibitors, the mixture of apamin+charybdotoxin or sulfaphenazole, before leptin administration. Leptin increased NO production, as evidenced by increase in plasma and urinary NO metabolites and cyclic GMP. This effect was impaired in both obese groups. In lean rats either leptin or EDHF inhibitors had no effect on blood pressure. L-NAME increased blood pressure in lean animals and this effect was prevented by leptin. However, when leptin was administered to animals pretreated with both L-NAME and EDHF inhibitors, blood pressure increased even more than after L-NAME alone. In the 1-month obese group leptin had no effect on SBP, however, pressor effect of leptin was observed in animals pretreated with EDHF inhibitors. In the 3-month obese group leptin alone increased SBP, and EDHF inhibitors did not augment its pressor effect. The results suggest that leptin may stimulate EDHF when NO becomes deficient, e.g. after NOS blockade or in short-term obesity. Although the effect of leptin on NO production is impaired in the 1-month obese group, BP does not increase, probably because EDHF compensates for NO deficiency. In contrast, leptin increases BP in 3-month obesity because its effect on EDHF is also attenuated.

[The management of velopharyngeal insufficiency after pharyngeal augmentations and furlow surgery]. / Leczenie niewydolnosci podniebienno-gardlowej metoda Furlowa i uwypukleniem tylnej sciany gardla.

INTRODUCTION: The term insuffisance velopalatine was first used by Larmoyez in 1892 r. Nowadays the term is used to denote the failure of the palate to produce velopharyngeal closure that would completely block the nasopharynx from the lower pharynx during physiological processes of swallowing, blowing, speaking, breathing and ventilation of the internal auditory canal. Numerous surgical techniques used in the treatment of VPI were described in the past 100 years. Several techniques have been used to decrease the velopharyngeal space, like operations aiming at bulging of the posterior pharyngeal wall and alternating "Z-plasty" of the soft palate aiming at prolongation and improvement of the mobile function of the palate. MATERIAL AND METHOD: The prospective studies were carried on from May 2003 to October 2004. Patients with severe forms of VPI were qualified for surgical treatment by a phoniatrist, speech therapist and plastic surgeon. All the surgical procedures were performed by the same surgeon. Bulging of the posterior pharyngeal wall by means of corionic graft was performed in 8 patients as the first stage treatment followed by prolongation of the palate by means of Furlow's technique 6 months later. The anatomical conditions as well as speech quality prior to, after the first and the second procedure were evaluated on the basis of direct examination, speech assessment, nasofibroscopic examinations and nasometric measurements. RESULTS: Examinations performed 6 months after termination of surgical treatment revealed improvement or significant improvement in speech quality, especially concerning reduced nasality, speech intelligibility and decreased nasal airflow (on an average from 48% to 33%). Five patients rated in questionnaires the outcome of treatment as "significant improvement". CONCLUSION: Complex staged management consisting in bulging of the posterior pharyngeal wall and Furlow's operation appeared to be a successful modality of treatment in patients with severe forms of velo-pharyngeal insufficiency in about 75% of cases.