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The undercarboxylated form of osteocalcin (ucOC) is an emerging marker of cardiovascular disease. It is unknown if ucOC in related to common cardiovascular risk markers in children. In offspring of families with and without metabolic syndrome (MetS+ and MetS- families), we assessed whether ucOC was related to a continuous metabolic syndrome score (MetS score) and to carotid intima-media thickness (cIMT).ucOC and total OC, MetS score and cIMT were assessed in 203 asymptomatic prepubertal children (age 7.6 ± 0.1 yr; 49% girls), of whom 99 were from MetS+ families.In children from MetS+ families, percent ucOC was higher than in children from MetS- families (p0.01). In offspring from MetS+ families, higher ucOC and especially higher percent ucOC was independently associated with both the MetS score and cIMT (both p ≤ 0.01).The undercarboxylated form of OC is related to common cardiovascular risk markers in children at risk for cardiovascular disease.

Glyphosate-based herbicides are extensively used for weed control all over the world. Therefore, it is important to investigate the putative toxic effects of these formulations which include not only glyphosate itself but also surfactants that may also be toxic. 3T3-L1 fibroblasts are a useful tool to study adipocyte differentiation, this cell line can be induced to differentiate by addition of a differentiation mixture containing insulin, dexamethasone and 3-isobutyl-1-methylxanthine. We used this cell line to investigate the effect of a commercial formulation of glyphosate (GF) on proliferation, survival and differentiation. It was found that treatment of exponentially growing cells with GF for 48 h inhibited proliferation in a dose-dependent manner. In addition, treatment with GF dilution 1:2000 during 24 or 48 h inhibited proliferation and increased cell death, as evaluated by trypan blue-exclusion, in a time-dependent manner. We showed that treatment of 3T3-L1 fibroblasts with GF increased caspase-3 like activity and annexin-V positive cells as evaluated by flow cytometric analysis, which are both indicative of induction of apoptosis. It was also found that after the removal of GF, remaining cells were able to restore proliferation. On the other hand, GF treatment severely inhibited the differentiation of 3T3-L1 fibroblasts to adipocytes. According to our results, a glyphosate-based herbicide inhibits proliferation and differentiation in this mammalian cell line and induces apoptosis suggesting GF-mediated cellular damage. Thus, GF is a potential risk factor for human health and the environment.

Adipogenesis is stimulated in 3T3-L1 fibroblast by a combination of insulin, dexamethasone, and methylisobutylxanthine (MIX). Mitotic clonal expansion (MCE) precedes differentiation of 3T3-L1 fibroblast to adipocytes. MIX increases cAMP content, which is the activator of protein kinase A (PKA). However, PKA-independent cAMP signaling has also been described. In this paper, it was found that H89, an inhibitor of PKA, was able to block MCE but not differentiation of 3T3-L1 fibroblast. Consistently, MCE did not occur in the absence of MIX in the differentiation mixture but was recovered by overexpression of a catalytic subunit of PKA. In addition, the transfection of 3T3-L1 fibroblast with a dominant-negative mutant of PKA inhibited MCE. On the other hand, differentiation of 3T3-L1 fibroblast to adipocytes did not occur when MIX was not present in the differentiation mixture and it could not be recovered by overexpression of a catalytic subunit of PKA. Differentiation was restored by addition of either dibutyryl-cAMP (db-cAMP) or 8 CPT-2 Me-cAMP. The latter activates cAMP-EPAC but not PKA signaling. These results indicate that cAMP-PKA-independent signaling, is required for 3T3-L1 fibroblasts differentiation to adipocytes and MIX signaling through cAMP-PKA is necessary for MCE, although MCE is not essential for adipogenesis.

Norfloxacin is highly effective in preventing spontaneous bacterial peritonitis recurrence in cirrhosis, but its role in the primary prevention of this complication is uncertain.Patients with cirrhosis and low protein ascitic levels (15 g/L) with advanced liver failure (Child-Pugh scoreor = 9 points with serum bilirubin levelor = 3 mg/dL) or impaired renal function (serum creatinine levelor = 1.2 mg/dL, blood urea nitrogen levelor = 25 mg/dL, or serum sodium levelor = 130 mEq/L) were included in a randomized controlled trial aimed at comparing norfloxacin (35 patients) vs placebo (33 patients) in the primary prophylaxis of spontaneous bacterial peritonitis. The main end points of the trial were 3-month and 1-year probability of survival. Secondary end points were 1-year probability of development of spontaneous bacterial peritonitis and hepatorenal syndrome.Norfloxacin administration reduced the 1-year probability of developing spontaneous bacterial peritonitis (7% vs 61%, P.001) and hepatorenal syndrome (28% vs 41%, P = .02), and improved the 3-month (94% vs 62%, P = .003) and the 1-year (60% vs 48%, P = .05) probability of survival compared with placebo.Primary prophylaxis with norfloxacin has a great impact in the clinical course of patients with advanced cirrhosis. It reduces the incidence of spontaneous bacterial peritonitis, delays the development of hepatorenal syndrome, and improves survival.

Reports about antioxidant effect in obesity are contradictory. We showed that N-acetylcysteine (NAC) inhibits cellular lipid accumulation during adipocyte differentiation, through the inhibition of adipogenic transcriptor factors expression, such as PPARγ and, MAPKs phosphorylation (Pieralisi et al,Redox Biol 2016; Soto el al,Redox Rep 2016). Here we evaluated NAC on fully differentiated cells (3T3-L1 adipocytes: AC). Treatments with 0.01 to 5 mM NAC, included in culture media for 5 days, were not toxic. 5mM NAC treatment on AC (ACN) provoked a decrease of 60% in cellular Triglycerides (Tg) content (1.22+0.09 gTg/g protein [AC] vs 0.49+0.03 gTg/g protein [ACN], p

Long-term primary antibiotic prophylaxis of spontaneous bacterial peritonitis has been suggested to be useful in cirrhotic patients with low ascitic fluid protein levels. However, it is unlikely that all such patients need prophylactic treatment. The aim of this study was to identify the group of cirrhotic patients with low ascitic fluid protein levels at high risk of developing a first episode of spontaneous bacterial peritonitis during outpatient follow-up.One hundred nine cirrhotic patients with low ascitic fluid protein levels and without previous episodes of spontaneous bacterial peritonitis were followed up in an outpatient clinic.Twenty-eight patients developed a first spontaneous bacterial peritonitis episode. In the multivariate analysis, serum bilirubin level (3.2 mg /dL) and platelet count (98.000/mm(3)) independently correlated with the risk of developing the first spontaneous bacterial peritonitis (P0.01 and P0.05, respectively). According to the median relative risk coefficient, a low-risk group (relative risk1.09) and a high-risk group (relative risk1.09) were established. The probability of developing a first spontaneous bacterial peritonitis episode at 1-year follow-up was significantly higher in the high risk-group (low-risk group, 23.6%; high-risk group, 55%; P0.01) as a consequence of a higher probability of the first community-acquired episode (13.7% vs. 47.6%, respectively, P0.01). One-year probability of survival was significantly lower in the high-risk group (low-risk group, 57.6%; high-risk group, 38%, P0.05).Cirrhotic patients with low ascitic fluid protein levels (/=1 g /dL) and high bilirubin level and/or low platelet count are at high risk of developing a first episode of spontaneous bacterial peritonitis during long-term follow-up.

Interest in extra-adrenal corticosteroid synthesis has been revived by technological advances and the quest for answers to clinical problems. The cytochrome P450 21-hydroxylase converts progester-one to deoxycorticosterone, the obligatory substrate for the production of the main adrenal steroids aldosterone, cortisol and corticosterone. The rat P450 21-hydroxylase was cloned and two constructs, 21OH-5 and 21OH-6, sequenced. The constructs are similar, except that 21OH-6 has three additional major insertions of 64, 70 and 84 bp, a 3 bp deletion, and four extra base pairs immediately before the poly-A sequence. The entire coding region of 21OH-5 has 87 and 71% homology with the mouse and human 21-hydroxylase cDNA, respectively, whereas the encoded protein has 84 and 65% homology. Reverse transcriptase-polymerase chain reaction (RT-PCR) combined with Southern blot demonstrated expression of both transcripts in the kidney, aorta, liver, cerebellum, hypothalamus and brain stem, heart and cerebrum, but not the hippocampus, in addition to the adrenal. The entire coding region of 21OH-5 and the corresponding region of 21OH-6 including the three introns were cloned into pCR3 and the plasmids transiently transfected into COS-7 cells. Only 21OH-5 was translated into active protein, converting approximately 64% of 3H-progesterone to deoxycorticosterone in 2 h.

We describe the effect of an inositol phosphoglycan (IPG) purified from Trypanosoma cruzi on the stimulation of aldosterone and cAMP production by ACTH in calf adrenocortical cells. T. cruzi IPG has two galactofuranose residues (Galf) which are not frequent in other IPGs. The effect of IPG with galactofuranose residues (IPG Galf) and IPG without these residues (IPG) was investigated. It was found that IPG Galf slightly decreased the stimulation of aldosterone and cAMP production by ACTH, whereas IPG significantly inhibited ACTH-mediated accumulation of both aldosterone and cAMP. The inhibition of aldosterone content in ACTH-treated cells by IPG was dose dependent. It was also found that the pretreatment of calf adrenocortical cells with IPG inhibited the accumulation of aldosterone provoked by ACTH and dibutyryladenosine-3′,5′-cyclic monophosphate (db-cAMP). On the other hand, the activation of a GPI (glycosyl phosphatidylinositol)-phospholipase C by ACTH was evaluated. First it was found that the release of ceramide from a GPI-like molecule: a glycoinositol-phosphoceramide (LPPG) purified from T. cruzi is increased in ACTH-treated cells. Second, the release of alkaline phosphatase, a GPI-anchored enzyme, to the extracellular medium was increased in these cells by ACTH. These data suggest that ACTH activates a phospholipase C in calf adrenocortical cells, releasing IPG, which in turn may inhibit, or modulate ACTH action.

Endothelin (ET-1) receptors were studied in the C-6 glia cell line. ET-1 binds to C-6 cells in a temperature- and time-dependent manner, with an apparent Kd of 1.16 +/- 0.07 10(-10) M and a Bmax of 96,500 +/- 6000 sites/cell (mean +/- SEM, n = 27). Stimulation of protein kinase C (PKC) with the diacylglycerol (DAG) analog phorbol 12-myristate 13-acetate (PMA) resulted in a decrease in the number of receptors in a dose-dependent manner. Inhibition of PKC with H-7 eliminated the effect of PMA on the reduction of binding sites. Treatment with exogenous 1-oleoyl-2-acetyl-sn-glycerol (OAG) and 1,2-dioctanoyl-sn-glycerol (DOG), release of endogenous DAG with phospholipase C, and inhibition of the metabolism of DAG with the diacylglycerol kinase inhibitor R 59022 also resulted in a decrease in the number of receptors. The effect of these agents was inhibited by H-7. ET-1-mediated down-regulation of receptors was also demonstrated, but the down-regulation was not affected by H-7 or by depletion of cellular PKC with chronic, high dose of PMA. Internalization constants of ET-1-receptor complex was also measured according to the model of Wiley and Cunningham (Cell 25 (1981) 433). PMA- and ET-1-mediated down-regulation of receptors was associated with an increase in the endocytosis constant for the hormone-receptor complex and a decrease in the rate of insertion of receptor into the plasma membrane. PMA, but not ET-1, increased the rate of endocytosis of unoccupied receptors. Radioiodinated ET-1 was crosslinked to the receptor after binding, extracted and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A band at 66 kDa was obtained. These studies show that ET-1 and PKC activation produce down-regulation of ET-1 membrane receptors and that ET-1-mediated down-regulation probably does not involve the activation of PKC.

Aldosterone production from 11-deoxycorticosterone was stimulated by hemin in primary cultures and homogenates of calf adrenal zona glomerulosa, in a time- and dose-dependent fashion. The ferrochelatase inhibitor 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine (DDC) blocked the stimulation of aldosterone mediated by adrenocorticotropin (ACTH). Addition of hemin after treatment with DDC partially restored ACTH action. These results suggest that hemin may play a role in regulation of aldosterone production.

Glycerol-3-phosphate acyltransferase (G3PAT) was activated by insulin in intact rat adipocytes within 1 min: this activation persisted for 10 min, and was due to a decrease in the Km of the enzyme. The addition of insulin to control adipocyte membranes also increased G3PAT activity, and this effect was mimicked by phosphatidylinositol-specific phospholipase C. Cytosol fractions from insulin-treated adipocytes stimulated G3PAT activity of control membranes, suggesting that a soluble mediator is released during insulin action, possibly through activation of a PI-specific PLC.

Summary Primary cultures of calf adrenal glomerulosa cells were prelabeled for 3 days with [ 3 H]inositol or [ 3 H]glucosamine and stimulated with 10 nM ACTH. Labeled phosphatidylinositol (PI), polyphosphoinositides (PIP and PIP 2 ) and a novel phosphatidylinositol-glycan (PI-glycan) were measured after separation by TLC. [ 3 H]-Inositol labeling of PI, PIP and PIP2 increased rapidly, whereas labeling of the PI-glycan showed an initial decrease at 1 minute followed by a subsequent increase. Similar results were obtained when cells were prelabeled with [ 3 H]glucosamine, viz. the PI-glycan label decreased at 1 min and subsequently increased. These results suggest that ACTH provokes (a) coordinated increases in the synthesis of PI, PIP, PIP2 and the PI-glycan, and (b) the increase in PI-glycan synthesis is preceded by initial decrease, presumably reflecting hydrolysis of this lipid.