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Niacin is a broad-spectrum lipid-regulating drug used for clinical therapy of chronic high-grade inflammatory diseases. However, the mechanisms by which either niacin or the byproducts of its catabolism ameliorate these inflammatory diseases are not clear yet. Human circulating monocytes and mature macrophages were used to analyze the effects of niacin and its metabolites (NAM, NUA and 2-Pyr) on oxidative stress, plasticity and inflammatory response by using biochemical, flow cytometry, quantitative real-time PCR and Western blot technologies. Niacin, NAM and 2-Pyr significantly decreased ROS, NO and NOS2 expression in LPS-treated human mature macrophages. Niacin and NAM skewed macrophage polarization toward antiinflammatory M2 macrophage whereas a trend toward proinflammatory M1 macrophage was noted following treatment with NUA. Niacin and NAM also reduced the inflammatory competence of LPS-treated human mature macrophages and promoted bias toward antiinflammatory CD14+CD16++ nonclassical human primary monocytes. This study reveals for the first time that niacin and its metabolites possess antioxidant, reprogramming and antiinflammatory properties on human primary monocytes and monocyte-derived macrophages. Our findings imply a new understanding of the mechanisms by which niacin and its metabolites favor a continuous and gradual plasticity process in the human monocyte/macrophage system.

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SCOPE: Postprandial state is directly linked with chronic diseases. We hypothesized that dietary fats may have acute effects on health status by modulating osteoclast differentiation and activation in a fatty acid-dependent manner. METHODS AND RESULTS: In healthy subjects, a fat-enriched meal increased plasma levels of the RANKL (receptor activator of nuclear factor κB ligand)/OPG (osteoprotegerin) ratio (SFAs > MUFAs = PUFAs) in the postprandial state. Postprandial TRL-SFAs enhanced tartrate-resistant acid phosphatase (TRAP) activity and the expression of osteoclast marker genes (TRAP, OSCAR, RANK, and CATHK) while downregulated the expression of OPG gene in human monocyte-derived osteoclasts. These effects were not observed with monounsaturated fatty acid (MUFA)-enriched postprandial triglyceride-rich lipoproteins (TRLs). Moreover, postprandial TRL-SFAs increased the release of osteoclastogenic cytokines (TNF-α, IL-1ß, and IL-6) meanwhile TRL-MUFAs and TRL-PUFAs increased the release of anti-osteoclastogenic cytokines (IL-4 and IL-10) in the medium of human monocyte-derived osteoclasts. CONCLUSION: For the first time, we show that postprandial TRLs are metabolic entities with osteoclastogenic activity and that this property is related to the type of dietary fatty acid in the meal. The osteoclastogenic potency was as follows: SFAs >>> MUFAs = PUFAs. These exciting findings open opportunities for developing nutritional strategies with olive oil as the principal dietary source of MUFAs, notably oleic acid, to prevent development and progression of osteoclast-related diseases.

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The well-known changes in modern lifestyle habits including over nutrition and physical inactivity have led to striking adverse effects on public health (e.g., obesity, diabetes, and metabolic syndrome) over recent decades. One noticeable consequence is exaggerated and prolonged state of postprandial hyperlipemia due to the ingestion of multiple fat-enriched meals during the course of a day. Postprandial (non-fasting) hyperlipemia is characterized by increased blood levels of exogenous triglycerides (TG) in the form of apolipoprotein (apo) B48-containing TG-rich lipoproteins (TRL), which have a causal role in the pathogenesis and progression of cardiovascular disease (CVD). The cardiovascular benefits of lifestyle modification (healthy diet and exercise) and conventional lipid-lowering therapies (e.g., statins, fibrates, and niacin) could involve their favourable effects on postprandial metabolism. Pharmacologically, niacin has been used as an athero-protective drug for five decades. Studies have since shown that niacin may decrease fasting levels of plasma verylow- density lipoproteins (VLDL), low-density lipoprotein cholesterol (LDL-C), and lipoprotein [a] (Lp[a]), while may increase high-density lipoprotein cholesterol (HDL-C). Herein, the purpose of this review was to provide an update on effects and mechanisms related to the pharmacological actions of niacin on acute hyperlipemia.

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Postprandial triglyceride-rich lipoproteins (TRLs) lead to a complex series of events that are potentially oxidative and inflammatory. The main goal of this study was to characterize the influence of postprandial TRLs with different fatty acid compositions (mainly SFAs, MUFAs or MUFAs plus omega-3 PUFAs) on oxidative and inflammatory markers in RPE cells, which play a pivotal role in age-related macular degeneration (AMD). Compared to TRL-SFAs, TRL-MUFAs and TRL-MUFAs plus omega-3 PUFAs decreased the production of ROS and nitrite, and the gene expression and secretion of IL-1ß, IL-6, TNF-α, IFNγ and VEGF. For the first time we show that postprandial TRLs are metabolic entities able to induce RPE oxidative stress and inflammation in a fatty acid-dependent manner, TRL-SFAs ⋙ TRL-MUFAs = TRL-MUFAs plus omega-3 PUFAs. These exciting findings open new opportunities for developing novel nutritional strategies with olive oil as the principal dietary source of oleic acid to prevent the development and progression of AMD.

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Existen dos maneras de conducir la segunda fase del parto: pujos espontáneosy pujos dirigidos. Los pujos espontáneos constituyen la maneranatural de conducir la segunda etapa del parto, sin embargo, últimamente,como consecuencia del uso de la analgesia epidural, losprofesionales recurren con frecuencia al manejo dirigido, sin considerarsus repercusiones negativas.El objetivo de este trabajo ha sido analizar comparativamente la evidenciadisponible sobre el efecto obstétrico, perinatal y materno de lospujos espontáneos frente a los pujos dirigidos.Metodología: revisión bibliográfica de las bases de datos Pubmed, CINAHLy Cochrane, entre los años 1995 y 2008, con las siguientes palabras clave:pushing, second stage labor, delayed pushing, passive fetal descent.Se recogieron datos sobre duración del expulsivo, tiempo de pujo, partosinstrumentales, alteraciones del patrón cardiaco fetal, desaturaciones,valores de PO2, PCO2 y pH fetales, test de Apgar, resultados perineales,fatiga y satisfacción materna en ambos tipos de pujo.Resultados: según las investigaciones realizadas, los pujos espontáneosque permiten el descenso pasivo fetal conllevan menos efectos adversos anivel materno y fetal. El pujo espontáneo es un método seguro para madree hijo en el manejo del período expulsivo. Aunque se observa un aumentodel tiempo de la segunda fase del parto, se reduce el tiempo de pujo,siendo éste el parámetro que realmente conlleva repercusiones negativas (AU)

There are two ways of directing the second stage of labour: spontaneouspushing and directed pushing. Spontaneous pushing represent a naturalway of managing the second stage of labour; however, lately, and as aresult of epidural analgesia, healthcare professionals frequently resortto directed pushing without taking into account the negative repercussionsit has on the patient.The aim of this work was to perform a comparative analysis of theavailable evidence on the obstetrical, perinatal and maternal effects ofspontaneous vs directed pushing.Methodology: bibliographic review of the Pubmed, CINAHL andCochrane databases, between the years 1995 and 2008, under thefollowing tag words: “pushing”, “second stage labour”, “delayed pu -shing”, “passive foetal descent”.Data were collected on the duration of the expulsion stage, pushing time,instrumental deliveries, alterations of the foetal cardiac pattern, disa -turations, PO2, PCO2 and pH foetal values, Apgar score, perineal outcome,fatigue and tiredness and maternal satisfaction with both types of pushing.Results: according to research, spontaneous pushing permits the passivedescend of the foetus and results in fewer maternal and foetal adverseeffects. Spontaneous pushing is a safe method for mother and baby in themanagement of the expulsion stage. Even though, an increase in the durationof the second stage of labour is observed, the pushing time is reduced,this being the parameter that really entails negative repercussions (AU)

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