Browsing by Author "Echeverria, Francisca"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    ANTI-STEATOTIC EFFECTS OF DOCOSAEXAENOIC ACID AND HYDROXYTYROSOL IN THE LIVER OF MICE FED A HIGH-FAT DIET: PPAR-A AND NRF2 UP-REGULATION, AND OF SRBP-1C AND NF-KB DOWN-REGULATION
    (2017) Valenzuela Baez, Rodrigo Wladmir; Echeverria, Francisca; Soto Alarcon, Sandra Anakaren; Orellana, Paula; Rincon-Cervera, Miguel Angel; Vargas, Romina; Valenzuela, Alfonso; Videla, Luis A.
    Background: Non-alcoholic fatty liver disease (NAFLD) is characterized by abnormal accumulation of lipids, being insulin resistance, oxidative stress, inflammation and a drastic depletion of n-3 LCPUFA the main expressions of the disease. Docosahexaenoic acid (DHA, 22:6, n-3) controls liver lipid metabolism by stimulation of lipolysis and inhibition of lipogenesis and Hydroxytyrosol (HT) exhibits strong tissue cytoprotective effects. Objetive: To evaluate the molecular mechanisms involved in the protective effects of a mixture of DHA and HT (DHA /HT), to prevent the development of NAFLD induced by high-fat diet (HFD) in mice. Methods: Male C57BL/6J mice received control diet (CD) (10% fat) or high fat diet (HFD - 60% fat), non-supplemented/ supplemented of DHA (50 mg per kg per day)/ HT (5 mg per kg per day) for 12 weeks. Parameters studied included liver histology (optical microscopy), activity of hepatic antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase (by spectrophotometry), oxidative stress indicators (glutathione, thiobarbituric acid reactants, and the antioxidant capacity of plasma), gene expression assays for PPAR-α, Nrf2, SREBP-1c and NF-κB (qPCR and ELISA), and LCPUFA profiles in liver (gas-liquid chromatography). Results: Results: HFD induced (i) liver steatosis (increasing total fat, triacylglycerols and free fatty acid content), (ii) higher fasting serum glucose, insulin levels and HOMA index, total cholesterol, triacylglycerols, TNF-α and IL-6, (iii) liver and plasma oxidative stress enhancement, (iv) depletion of n-3 LCPUFA content of liver phospholipids, increasing lipogenic and reducing lipolytic enzyme activities (v) down-regulation of PPAR-α and Nrf2, and (vi) up-regulation of SREBP-1c and NF-kB (gene expression and DNA binding activity). These changes were either reduced (p < 0.05) or normalized (compared to CD) in animals feed HFD supplemented with DHA/HT. Conclusions: DHA/HT intervention exerts anti-steatotic effects underling antioxidants and anti-inflammatory responses by improving insulin sensitivity and recovering the lipolytic/lipogenic status of the liver altered by HFD, being PPAR-α and Nrf2 up-regulation, together with SREBP-1c and NF-κB down-regulation important molecular mechanisms involved in the protective action of DHA/HT. These effects may support the potential therapeutic use of DHA/HT supplementation in the treatment of liver steatosis induced by nutritional factors and/or other etiologies. Keywords: Anti-steatotic effects; docosahexaenoic acid; hydroxytyrosol; antioxidant effects ; antiinflammatory effects
  • No Thumbnail Available
    Item
    Impact of polyunsaturated fatty acids during and pregnancy and lactation: A comprehensive review
    (2024) Munoz, Yasna; Mercado, Lorena; Farias, Camila; Beyer, Maria Paz; Alvear, Ignacio; Echeverria, Francisca; Valenzuela, Rodrigo
    Background: Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are relevant polyunsaturated fatty acids (PUFA) derived from alpha-linolenic acid (ALA) and linoleic acid (LA), respectively. These are important in pregnancy and lactation periods because of their benefits to the developing fetus and infant. Currently, the high prevalence of gestational obesity has led to a revision of PUFAs recommendations in these periods, due to changes in the lipid profile of women marked by a higher consumption of n-6 PUFA. Objective: This review aims to present an updated compilation of evidence on DHA and ARA during gestation and lactation. Methods: The literature review was performed in different databases, PubMed, Scopus, Web of Science, Scielo, ISI, and Ovid MedLine, highlighting the importance of DHA and ARA for newborn development. Results: An adequate intake of n-3 PUFA, especially DHA, in the mother during pregnancy and the postnatal period is important for the normal development of the child's brain. Maternal DHA supplementation increases DHA levels in mothers, but its direct link to infant neurodevelopment remains unclear. Obesity generates changes in the FA profile of pregnant women, causing an imbalance of n-3 and n-6 PUFA. An adequate level of DHA benefits children's cognitive function. However, a potential connection exists to the infants' inflammatory profile. Conclusion: During gestation and lactation periods, an adequate DHA intake and n-6/ n-3 PUFA ratio (especially for obese women) are important for the optimal growth and brain development of the child.