Supplementation with antioxidant-rich extra virgin olive oil prevents hepatic oxidative stress and reduction of desaturation capacity in mice fed a high-fat diet: Effects on fatty acid composition in liver and extrahepatic tissues

Gut Microbiota and Metabolic Dysfunction-Associated Steatotic Liver Disease

Background: The gut microbiota constitutes a complex microorganism community that harbors bacteria, viruses, fungi, protozoa, and archaea. The human gut bacterial microbiota has been extensively proven to participate in human metabolism, immunity, and nutrient absorption. Its imbalance, namely "dysbiosis", has been linked to disordered metabolism. Metabolic dysfunction-associated steatotic liver disease (MASLD) is one of the features of deranged human metabolism and is the leading cause of liver cirrhosis and hepatocellular carcinoma. Thus, there is a pathophysiological link between gut dysbiosis and MASLD. Aims and Methods: We aimed to review the literature data on the composition of the human bacterial gut microbiota and its dysbiosis in MASLD and describe the concept of the "gut-liver axis". Moreover, we reviewed the approaches for gut microbiota modulation in MASLD treatment. Results: There is consolidated evidence of particular gut dysbiosis associated with MASLD and its stages. The model explaining the relationship between gut microbiota and the liver has a bidirectional organization, explaining the physiopathology of MASLD. Oxidative stress is one of the keystones in the pathophysiology of MASLD and fibrosis generation. There is promising and consolidated evidence for the efficacy of pre- and probiotics in reversing gut dysbiosis in MASLD patients, with therapeutic effects. Few yet encouraging data on fecal microbiota transplantation (FMT) in MASLD are available in the literature. Conclusions: The gut dysbiosis characteristic of MASLD is a key target in its reversal and treatment via diet, pre/probiotics, and FMT treatment. Oxidative stress modulation remains a promising target for MASLD treatment, prevention, and reversal.

Time-restricted feeding relieves high temperature-induced impairment on meat quality by activating the Nrf2/HO-1 pathway, modification of muscle fiber composition, and enriching the polyunsaturated fatty acids in pigs

To assess the effects of a time-restricted feeding (TRF) regimen on meat quality of pigs exposed to high ambient temperature, a two-month feeding and heat treatment (HT) trial was conducted using a 2 × 2 factorial design. A total of 24 growing pigs (11.0 ± 1.9 kg) were randomly divided into four groups: thermal neutral group (NT, 24 ± 3 °C), HT group (exposed to a high temperature at 35 ± 2 °C from 11:00 to 15:00), TRF group and HT + TRF group (HT and TRF co-treatment group, n = 6 for each group). Pigs in TRF groups got access to feed within 5 h from 9:00 to14:00, while the others were fed at 6:00, 11:30, and 16:00. All pigs received the same diet during the trail. The results showed that HT increased the drip loss, shear force, lightness, and malondialdehyde production in Longissimus thoracis et lumborum (LTL) muscle. TRF reversely reduced the shear force and drip loss, accompanied by decreased intramuscular fat and increased moisture content. Enhanced fiber transformation from type 1 to type 2b and down-regulated expression of muscle growth-related genes were observed by HT, while TRF suppressed the fiber transformation and expression of muscle atrophy-related genes. Furthermore, TRF restored the diminished protein expressions of Nrf2 and HO-1 in LTL muscle by chronic HT. Accumulation of HSP70 in muscle of HT group was reduced by treatment of TRF. HT declined the expression of vital genes involved in fatty acids poly-desaturation and the proportion of (polyunsaturated fatty acids) PUFAs, mainly omega-6 in LTL muscle, while TRF group promoted the expression of poly-desaturation pathway and displayed the highest proportion of PUFAs. These results demonstrated that TRF relieved the chronic high temperature affected meat quality by the restored expression of Nrf2/HO-1 anti-oxidative cascade, modified muscle fiber composition, and enriched PUFAs in LTL muscle.

Exploring the Impact of Extra Virgin Olive Oil on Maternal Immune System and Breast Milk Composition in Rats

Maternal breast milk plays a key role in providing newborns with passive immunity and stimulating the maturation of an infant's immune system, protecting them from many diseases. It is known that diet can influence the immune system of lactating mothers and the composition of their breast milk. The aim of this study was to establish if a supplementation during the gestation and lactation of Lewis rats with extra virgin olive oil (EVOO), due to the high proportion of antioxidant components in its composition, has an impact on the mother's immune system and on the breast milk's immune composition. For this, 10 mL/kg of either EVOO, refined oil (control oil) or water (REF group) were orally administered once a day to rats during gestation and lactation periods. Immunoglobulin (Ig) concentrations and gene expressions of immune molecules were quantified in several compartments of the mothers. The EVOO group showed higher IgA levels in both the breast milk and the mammary glands than the REF group. In addition, the gene expression of IgA in mammary glands was also boosted by EVOO consumption. Overall, EVOO supplementation during gestation and lactation is safe and does not negatively affect the mother's immune system while improving breast milk immune composition by increasing the presence of IgA, which could be critical for an offspring's immune health.

Limosilactobacillus fermentum Strains as Novel Probiotic Candidates to Promote Host Health Benefits and Development of Biotherapeutics: A Comprehensive Review

Fruits and their processing by-products are sources of potentially probiotic strains. Limosilactobacillus (L.) fermentum strains isolated from fruit processing by-products have shown probiotic-related properties. This review presents and discusses the results of the available studies that evaluated the probiotic properties of L. fermentum in promoting host health benefits, their application by the food industry, and the development of biotherapeutics. The results showed that administration of L. fermentum for 4 to 8 weeks promoted host health benefits in rats, including the modulation of gut microbiota, improvement of metabolic parameters, and antihypertensive, antioxidant, and anti-inflammatory effects. The results also showed the relevance of L. fermentum strains for application in the food industry and for the formulation of novel biotherapeutics, especially nutraceuticals. This review provides evidence that L. fermentum strains isolated from fruit processing by-products have great potential for promoting host health and indicate the need for a translational approach to confirm their effects in humans using randomized, double-blind, placebo-controlled trials.

Protein concentrations and activities of fatty acid desaturase and elongase enzymes in liver, brain, testicle, and kidney from mice: Substrate dependency

The synthesis rates of n-3 and n-6 polyunsaturated fatty acids (PUFAs) in rodents and humans are not agreed upon and depend on substrate availability independently of the capacity for synthesis. Therefore, we aimed to assess the activities of the enzymes for n-3 and n-6 PUFA synthesis pathways in liver, brain, testicle, kidney, heart, and lung, in relation to their protein concentration levels. Eight-week-old Balb/c mice (n = 8) were fed a standard chow diet (6.2% fat, 18.6% protein, and 44.2% carbohydrates) until 14 weeks of age, anesthetized with isoflurane and tissue samples were collected (previously perfused) and stored at -80°C. The protein concentration of the enzymes (Δ-6D, Δ-5D, Elovl2, and Elovl5) were assessed by ELISA kits; their activities were assayed using specific PUFA precursors and measuring the respective PUFA products as fatty acid methyl esters by gas chromatographic analysis. The liver had the highest capacity for PUFA biosynthesis, with limited activity in the brain, testicles, and kidney, while we failed to detect activity in the heart and lung. The protein concentration and activity of the enzymes were significantly correlated. Furthermore, Δ-6D, Δ-5D, and Elovl2 have a higher affinity for n-3 PUFA precursors compared to n-6 PUFA. The capacity for PUFA synthesis in mice mainly resides in the liver, with enzymes having preference for n-3 PUFAs.

The potential protectivity of honey and olive oil in methotrexate induced renal damage in rats

Methotrexate (MTX) is an antimetabolite used to treat inflammatory diseases, autoimmune disorders and some malignancies. However, it has some life-threatening side effects such as nephrotoxicity which limit its clinical applications. That motivated the attention to seek for a defensive material to improve the outcomes of methotrexate while minimizing both renal and non-renal toxicity. Both honey (H) and olive oil (OO) are bioactive substances widely used as nutraceuticals that exhibited a potent therapeutic and antioxidant properties. This study aimed to assess the possible protective effect of H and OO intake either singly or together against the biochemical and structural Methotrexate-induced nephrotoxicity in rats. The study was conducted on 56 adult albino rats, they were divided into seven groups (n = 8): group 1 received only distelled water (negative control), group 2 received H (1.2 g/kg/day), group 3 received OO (1.25 ml/kg/day), group 4 received a single intraperitoneal injection of MTX (20 mg/kg), group 5 received MTX and H, group 6 received MTX and OO, group 7 received MTX, H and OO together. At the end of the experiment (2 weeks), all rats were sacrificed, and blood samples were assessed for kidney function tests. Kidney tissues were evaluated for several antioxidant parameters including Malondialdehyde (MDA), Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities. Tissues were also processed for histological and immunohistochemical assessments. Results revealed that both H and OO improved the kidney function markers, histopathological and immunohistological changes due to Methotrexate-induced renal damage. Additionally, both substances also redeemed the oxidative damage of the kidney by decreasing MDA and increasing anti-oxidant enzymatic activities. Such effects were more apparent when the two substances were given together. Ultimately, our results proof that H and OO amiolerate the Methotrexate-induced nephrotoxicity in rats, thus they can be used as an adjuvant supplements for patients requiring methotrexate therapy.

Effects on Fetal Metabolic Programming and Endocannabinoid System of a Normocaloric Diet during Pregnancy and Lactation of Female Mice with Pregestational Obesity

Fetal programming provides explanatory mechanisms for the currently high prevalence of gestational obesity. The endocannabinoid system (ECS) participates in the regulation of energy balance, and with a high-fat diet (HFD), it is overactivated. The aim of this study was to determine the effects of a nutritional intervention during pregnancy and lactation on obese female progenitors, on metabolic alterations of the offspring and on the involvement of ECS. Female mice (C57/BL/6-F0), 45 days old, and their offspring (males) were separated according to type of diet before and during gestation and lactation: CON-F1: control diet; HFD-F1 group: HFD (fat: 60% Kcal); INT-F1 group: HFD until mating and control diet (fat: 10% Kcal) afterward. Glucose tolerance and insulin sensitivity (IS) were tested at 2 and 4 months. At 120 days, mice were sacrificed, plasma was extracted for the determination of hormones, and livers for gene expression and the protein level determination of ECS components. INT-F1 group presented a lower IS compared to CON-F1, and normal levels of adiponectin and corticosterone in relation to the HFD-F1 group. The intervention increased hepatic gene expression for fatty-acid amide hydrolase and monoacylglycerol lipase enzymes; however, these differences were not observed at the protein expression level. Our results suggest that this intervention model normalized some hormonal parameters and hepatic mRNA levels of ECS components that were altered in the offspring of progenitors with pre-pregnancy obesity.

Analysis of risk factors for parenteral nutrition-associated cholestasis in preterm infants: a multicenter observational study

BACKGROUND

It is proposed that the development of parenteral nutrition-associated cholestasis (PNAC) was significantly associated with preterm birth, low birth weight, infection, etc.; however, the etiology and pathogenesis of PNAC are not fully understood. Most of the studies examining PNAC-associated risk factors were single-center studies with relatively small sample sizes.

OBJECTIVE

To analyze the risk factors associated with PNAC in preterm infants in China.

METHODS

This is a retrospective multicenter observational study. Clinical data on the effect of multiple oil-fat emulsions (soybean oil-medium chain triglycerides-olive oil-fish oil, SMOF) in preterm infants were collected from a prospective multicenter randomized controlled study. A secondary analysis was performed in which preterm infants were divided into the PNAC group and the non-PNAC group based on the PNAC status.

RESULTS

A total of 465 cases very preterm infants or very low birth weight infants were included in the study in which 81 cases were assigned to the PNAC group and 384 cases were assigned to the non-PNAC group. The PNAC group had a lower mean gestational age, lower mean birth weight, longer duration of invasive and non-invasive mechanical ventilation, a longer duration oxygen support, and longer hospital stay (P < 0.001 for all). The PNAC group had higher respiratory distress syndrome, hemodynamically significant patent ductus arteriosus, necrotizing enterocolitis (NEC) with stage II or higher, surgically treated NEC, late-onset sepsis, metabolic bone disease, and extrauterine growth retardation (EUGR) compared to the non-PNAC group (P < 0.05 for all). In contrast with the non-PNAC group, the PNAC group received a higher maximum dose of amino acids and fat emulsion, more medium/long-chain fatty emulsion, less SMOF, had a longer duration of parenteral nutrition, lower rates of breastfeeding, higher incidence of feeding intolerance (FI), more accumulated days to achieve total enteral nutrition, less accumulated days of total calories up to standard 110 kcal/kg/day and slower velocity of weight growth (P < 0.05 for all). Logistic regression analysis indicated that the maximum dose of amino acids (OR, 5.352; 95% CI, 2.355 to 12.161), EUGR (OR, 2.396; 95% CI, 1.255 to 4.572), FI (OR, 2.581; 95% CI, 1.395 to 4.775), surgically treated NEC (OR, 11.300; 95% CI, 2.127 ~ 60.035), and longer total hospital stay (OR, 1.030; 95% CI, 1.014 to 1.046) were independent risk factors for the development of PNAC. SMOF (OR, 0.358; 95% CI, 0.193 to 0.663) and breastfeeding (OR, 0.297; 95% CI, 0.157 to 0.559) were protective factors for PNAC.

CONCLUSIONS

PNAC can be reduced by optimizing the management of enteral and parenteral nutrition and reducing gastrointestinal comorbidities in preterm infants.

Ferulic acid alleviates high fat diet-induced cognitive impairment by inhibiting oxidative stress and apoptosis

Cognitive impairment has become a major public health problem. Growing evidence suggests that high-fat diet (HFD) can cause cognitive dysfunction and increase the risk of dementia. However, effective treatment for cognitive impairment is not available. Ferulic acid (FA) is a single phenolic compound with anti-inflammatory and antioxidant properties. Nevertheless, its role in regulating learning and memory in HFD-fed mice and the underlying mechanism remains unclear. In this study, we aimed to identify the neuroprotective mechanisms of FA in HFD induced cognitive impairment. We found that FA improved the survival rate of HT22 cells treated with palmitic acid (PA), inhibited cell apoptosis, and reduced oxidative stress via the IRS1/PI3K/AKT/GSK3β signaling pathway; Furthermore, FA treatment for 24 weeks improved the learning and memory of HFD-fed mice and decreased hyperlipidemia. Moreover, the expression of Nrf2 and Gpx4 proteins were decreased in HFD-fed mice. After FA treatment, the decline of these proteins was reversed. Our study showed that the neuroprotective effect of FA on cognitive impairment was related to the inhibition of oxidative stress and apoptosis and regulation of glucose and lipid metabolism. These findings suggested that FA can be developed as a potential agent for the treatment of HFD-induced cognitive impairment.

Influence of the nutritional status and oxidative stress in the desaturation and elongation of n-3 and n-6 polyunsaturated fatty acids: Impact on non-alcoholic fatty liver disease

Polyunsaturated fatty acids (PUFA) play essential roles in cell membrane structure and physiological processes including signal transduction, cellular metabolism and tissue homeostasis to combat diseases. PUFA are either consumed from food or synthesized by enzymatic desaturation, elongation and peroxisomal β-oxidation. The nutritionally essential precursors α-linolenic acid (C18:3n-3; ALA) and linoleic acid (C18:2n-6; LA) are subjected to desaturation by Δ6D/Δ5D desaturases and elongation by elongases 2/5, enzymes that are induced by insulin and repressed by PUFA. Maintaining an optimally low n-6/n-3 PUFA ratio is linked to prevention of the development of several diseases, including nonalcoholic fatty liver disease (NAFLD) that is characterized by depletion of PUFA promoting hepatic steatosis and inflammation. In this context, supplementation with n-3 PUFA revealed significant lowering of hepatic steatosis in obese patients, whereas prevention of fatty liver by high-fat diet in mice is observed in n-3 PUFA and hydroxytyrosol co-administration. The aim of this work is to review the role of nutritional status and nutrient availability on markers of PUFA biosynthesis. In addition, the impact of oxidative stress developed as a result of NAFLD, a redox imbalance that may alter the expression and activity of the enzymes involved, and diminished n-3 PUFA levels by free-radical dependent peroxidation processes will be discussed.

High-dose ferric citrate supplementation attenuates omega-3 polyunsaturated fatty acid biosynthesis via downregulating delta 5 and 6 desaturases in rats with high-fat diet-induced obesity

Obesity is associated with an increased risk of an iron deficiency; however, a synergistic relationship between iron and lipid homeostasis was also observed. The aim of this study was to investigate the effects of pharmacological doses of iron supplementation on omega 3 (n-3) and omega 6 (n-6) polyunsaturated fatty acids (PUFAs). Sprague-Dawley (SD) rats were fed a normal diet or a 50% high-fat diet (HFD) without or with pharmacological doses of ferric citrate (0.25, 1, or 2 g ferric iron per kg diet) for 12 weeks, and erythrocyte profiles of n-3 and n-6 PUFAs were quantitated. Ferric citrate supplementation showed dose-related effects on liver inflammation, liver iron accumulation, and increasing circulating levels of iron, erythrocyte degradation biomarkers LVV-hemorphin-7, malondialdehyde (MDA), and insulin. Obese rats supplemented with 2 g ferric iron per kg diet also had decreased levels of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and total n-3 PUFAs compared to rats fed a normal diet or HFD alone. A western blotting analysis revealed that iron-mediated downregulation of n-3 PUFA-converting enzymes (Δ5 and Δ6 desaturases) only occurred at high dosages (≥1 g ferric iron per kg diet). A Spearman correlation analysis showed that total liver iron and serum LVV-hemorphin-7 and MDA were negatively correlated with n-3 PUFAs and their converting enzymes (Δ5 and Δ6 desaturases) (all p < 0.05). In conclusion, obese rats that received high-dose ferric citrate supplementation (>1 g of ferric iron per kg diet) exhibited decreased n-3 PUFA levels via downregulation of expressions of Δ5 and Δ6 desaturase enzymes.

Olive Oil: Nutritional Applications, Beneficial Health Aspects and its Prospective Application in Poultry Production

Plant polyphenols have promoting health features, including anti-mutagenic, anti-inflammatory, anti-thrombotic, anti-atherogenic, and anti-allergic effects. These polyphenols improve the immune system by affecting the white blood cell proliferation, as well as by the synthesis of cytokines and other factors, which contribute to immunological resistance. Olive trees are one of the most famous trees in the world. Whereas, olive olive oil and derivatives represent a large group of feeding resource for farm animals. In recent years, remarkable studies have been carried out to show the possible use of olive oil and derivatives for improvement of both animal performance and product quality. In vivo application of olive oil and its derived products has shown to maintain oxidative balance owing to its polyphenolic content. Consumption of extra virgin olive oil reduces the inflammation, limits the risk of liver damage, and prevents the progression of steatohepatitis through its potent antioxidant activities. Also, the monounsaturated fatty acids content of olive oil (particularly oleic acid), might have positive impacts on lipid peroxidation and hepatic protection. Therefore, this review article aims to highlight the nutritional applications and beneficial health aspects of olive oil and its effect on poultry production.

Phenethylamine in chlorella alleviates high-fat diet-induced mouse liver damage by regulating generation of methylglyoxal

This study examined the effects of oral administration of water extract of chlorella (WEC) (100 mg/kg bodyweight) and phenethylamine (10 μg/kg bodyweight) on high-fat diet (HFD)-induced liver damage in mice. Phenethylamine significantly mitigated HFD-induced lipid oxidation (generation of malondialdehyde) and liver damage without markedly decreasing hepatic lipid accumulation. WEC exerted similar effects although with decreased efficacy. In addition, WEC and phenethylamine decreased the methylglyoxal levels and increased the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein levels in the liver. Methylglyoxal is generated from substrates of GAPDH, dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. These facts indicate that methylglyoxal triggers oxidation of accumulated lipid, which generates malondialdehyde and consequently induces liver damage. Suppression of generation of toxic aldehydes by WEC and phenethylamine was also confirmed by maintaining hepatic cysteine, highly reactive to aldehydes. Thus, trace amounts of phenethylamine alleviate HFD-induced liver damage by regulating methylglyoxal via increase of GAPDH.

Intestinal GLUT5 and FAT/CD36 transporters and blood glucose are reduced by a carotenoid/MUFA-rich oil in high-fat fed mice

AIMS

Intestinal nutrient absorption plays a vital role in developing obesity, and nutrient transporters expressed in the enterocytes facilitate this process. Moreover, previous studies have shown that specific foods and diets can affect their cell levels. Herein, we investigated the effects of pequi oil (PO), which is high in several bioactive compounds, on intestinal nutrient transporter levels as well as on intestinal morphology and metabolic biomarkers.

MAIN METHODS

Groups of male C57BL/6 mice were fed either a standard (C) or a high-fat diet (HFD) and pequi oil (CP and HFDP with PO by gavage at 150 mg/day) for eight weeks. Food intake and body weight were monitored, serum metabolic biomarkers, intestinal transporter levels and histological analyses were performed.

KEY FINDINGS

PO increased caloric intake without increasing body or fat mass regardless of diet. The HFD group treated with PO reduced fasting blood glucose and villus width. PO did not affect GLUT2, L-FABP, FATP4, NPC1L1, NHE3 or PEPT1 content in CP or HFDP groups. GLUT5 and FAT/CD36 levels were reduced in both CP and HFDP.

SIGNIFICANCE

Our data suggest that PO attenuated monosaccharide and fatty acid absorption, contributing to lower fasting glycemia and higher food intake without affecting body weight or visceral fat of high-fat feed mice.

Changes in Human Erythrocyte Membrane Exposed to Aqueous and Ethanolic Extracts from Uncaria tomentosa

Uncaria tomentosa (Willd.) DC is a woody climber species originating from South and Central America that has been used in the therapy of asthma, rheumatism, hypertension, and blood purification. Our previous study showed that U. tomentosa extracts altered human erythrocyte shape, which could be due to incorporation of the compounds contained in extracts into the erythrocyte membrane. The aim of the present study was to determine how the compounds contained in U. tomentosa extracts incorporate into the human erythrocyte membrane. The study has assessed the effect of aqueous and ethanolic extracts from leaves and bark of U. tomentosa on the osmotic resistance of the human erythrocyte, the viscosity of erythrocyte interior, and the fluidity of erythrocyte plasma membrane. Human erythrocytes were incubated with the studied extracts in the concentrations of 100, 250, and 500 µg/mL for 2, 5, and 24 h. All extracts tested caused a decrease in erythrocyte membrane fluidity and increased erythrocyte osmotic sensitivity. The ethanolic extracts from the bark and leaves increased viscosity of the erythrocytes. The largest changes in the studied parameters were observed in the cells incubated with bark ethanolic extract. We consider that the compounds from U. tomentosa extracts mainly build into the outer, hydrophilic monolayer of the erythrocyte membrane, thus protecting the erythrocytes against the adverse effects of oxidative stress.

Cystine reduces tight junction permeability and intestinal inflammation induced by oxidative stress in Caco-2 cells

Intestinal oxidative stress produces pro-inflammatory cytokines, which increase tight junction (TJ) permeability, leading to intestinal and systemic inflammation. Cystine (Cys2) is a substrate of glutathione (GSH) and inhibits inflammation, however, it is unclear whether Cys2 locally improves intestinal barrier dysfunction. Thus, we investigated the local effects of Cys2 on oxidative stress-induced TJ permeability and intestinal inflammatory responses. Caco-2 cells were cultured in a Cys2-supplemented medium for 24 h and then treated with H₂O₂ for 2 h. We assessed TJ permeability by measuring transepithelial electrical resistance and the paracellular flux of fluorescein isothiocyanate–dextran 4 kDa. We measured the concentration of Cys2 and GSH after Cys2 pretreatment. The mRNA expression of pro-inflammatory cytokines was assessed. In addition, the levels of TJ proteins were assessed by measuring the expression of TJ proteins in the whole cells and the ratio of TJ proteins in the detergent-insoluble fractions to soluble fractions (IS/S ratio). Cys2 treatment reduced H₂O₂-induced TJ permeability. Cys2 did not change the expression of TJ proteins in the whole cells, however, suppressed the IS/S ratio of claudin-4. Intercellular levels of Cys2 and GSH significantly increased in cells treated with Cys2. Cys2 treatment suppressed the mRNA expression of pro-inflammatory cytokines, and the mRNA levels were significantly correlated with TJ permeability. In conclusion, Cys2 treatment locally reduced oxidative stress-induced intestinal barrier dysfunction possively due to the mitigation of claudin-4 dislocalization. Furthermore, the effect of Cys2 on the improvement of intestinal barrier function is related to the local suppression of oxidative stress-induced pro-inflammatory responses.

Impact of Maternal Obesity on the Metabolism and Bioavailability of Polyunsaturated Fatty Acids during Pregnancy and Breastfeeding

Prenatal and postnatal development are closely related to healthy maternal conditions that allow for the provision of all nutritional requirements to the offspring. In this regard, an appropriate supply of fatty acids (FA), mainly n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), is crucial to ensure a normal development, because they are an integral part of cell membranes and participate in the synthesis of bioactive molecules that regulate multiple signaling pathways. On the other hand, maternal obesity and excessive gestational weight gain affect FA supply to the fetus and neonate, altering placental nutrient transfer, as well as the production and composition of breast milk during lactation. In this regard, maternal obesity modifies FA profile, resulting in low n-3 and elevated n-6 PUFA levels in maternal and fetal circulation during pregnancy, as well as in breast milk during lactation. These modifications are associated with a pro-inflammatory state and oxidative stress with short and long-term consequences in different organs of the fetus and neonate, including in the liver, brain, skeletal muscle, and adipose tissue. Altogether, these changes confer to the offspring a higher risk of developing obesity and its complications, as well as neuropsychiatric disorders, asthma, and cancer. Considering the consequences of an abnormal FA supply to offspring induced by maternal obesity, we aimed to review the effects of obesity on the metabolism and bioavailability of FA during pregnancy and breastfeeding, with an emphasis on LCPUFA homeostasis.

Oxidative Stress in NAFLD: Role of Nutrients and Food Contaminants

Non-alcoholic fatty liver disease (NAFLD) is often the hepatic expression of metabolic syndrome and its comorbidities that comprise, among others, obesity and insulin-resistance. NAFLD involves a large spectrum of clinical conditions. These range from steatosis, a benign liver disorder characterized by the accumulation of fat in hepatocytes, to non-alcoholic steatohepatitis (NASH), which is characterized by inflammation, hepatocyte damage, and liver fibrosis. NASH can further progress to cirrhosis and hepatocellular carcinoma. The etiology of NAFLD involves both genetic and environmental factors, including an unhealthy lifestyle. Of note, unhealthy eating is clearly associated with NAFLD development and progression to NASH. Both macronutrients (sugars, lipids, proteins) and micronutrients (vitamins, phytoingredients, antioxidants) affect NAFLD pathogenesis. Furthermore, some evidence indicates disruption of metabolic homeostasis by food contaminants, some of which are risk factor candidates in NAFLD. At the molecular level, several models have been proposed for the pathogenesis of NAFLD. Most importantly, oxidative stress and mitochondrial damage have been reported to be causative in NAFLD initiation and progression. The aim of this review is to provide an overview of the contribution of nutrients and food contaminants, especially pesticides, to oxidative stress and how they may influence NAFLD pathogenesis.

Effect of dietary EPA and DHA on murine blood and liver fatty acid profile and liver oxylipin pattern depending on high and low dietary n6-PUFA

The intake of long-chain n3-polyunsaturated fatty acids (PUFA), which are associated with beneficial health effects, is low in the Western diet, while the portion of dietary n6-PUFA and hence the n6/n3-PUFA ratio is high. Strategies to improve the n3-PUFA status are n3-PUFA supplementation and/or lowering n6-PUFA intake. In the present study, mice were fed with two different sunflower oil-based control diets rich in linoleic (n6-high) or oleic acid (n6-low), either with low n3-PUFA content (∼0.02%) as control or with ∼0.6% eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). The n6-low diet had only little or no effect on levels of arachidonic acid (ARA) and its free oxylipins in liver tissue. Supplementation with EPA or DHA lowered ARA levels with an effect size of n6-high < n6-low. Blood cell %EPA + DHA reached >8% and >11% in n6-high and n6-low groups, respectively. Elevation of EPA levels and EPA derived oxylipins was most pronounced in n6-low groups in liver tissue, while levels of DHA and DHA derived oxylipins were generally unaffected by the background diet. While the n6-low diet alone had no effect on blood and liver tissue ARA levels or n3-PUFA status, a supplementation of EPA or DHA was more effective in combination with an n6-low diet. Thus, supplementation of long-chain n3-PUFA combined with a reduction of dietary n6-PUFA is the most effective way to improve the endogenous n3-PUFA status.

Targeting n-3 Polyunsaturated Fatty Acids in Non-Alcoholic Fatty Liver Disease

BACKGROUND

Non-Alcoholic Fatty Liver Disease (NAFLD) is characterized by abnormal hepatic accumulation of triacylglycerides in the absence of alcohol consumption, in association with Oxidative Stress (OS), a pro-inflammatory state and Insulin Resistance (IR), which are attenuated by n-3 long-chain polyunsaturated Fatty Acids (FAs) C20-C22 (LCPUFAs) supplementation. Main causes of NAFLD comprise high caloric intake and a sedentary lifestyle, with high intakes of saturated FAs.

METHODS

The review includes several searches considering the effects of n-3 LCPUFAs in NAFLD in vivo and in vitro models, using the PubMed database from the National Library of Medicine- National Institutes of Health.

RESULT

The LCPUFAs eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n- 3, DHA) have a positive effect in diminishing liver steatosis, OS, and the levels of aspartate aminotransferase, alanine aminotransferase and pro-inflammatory cytokines, with improvement of insulin sensitivity and adiponectin levels. The molecular pathways described for n-3 LCPUFAs in cellular and animal models and humans include peroxisome proliferator-activated receptor-α activation favouring FA oxidation, diminution of lipogenesis due to sterol responsive element binding protein-1c downregulation and inflammation resolution. Besides, nuclear factor erythroid-2-related factor-2 activation is elicited by n-3 LCPUFA-derived oxidation products producing direct and indirect antioxidant responses, with concomitant anti-fibrogenic action.

CONCLUSION

The discussed effects of n-3 LCPUFA supplementation support its use in NAFLD, although having a limited value in NASH, a contention that may involve n-3 LCPUFA oxygenated derivatives. Clinical trials establishing optimal dosages, intervention times, type of patients and possible synergies with other natural products are needed in future studies.

Exchanging dietary fat source with extra virgin olive oil does not prevent progression of diet-induced non-alcoholic fatty liver disease and insulin resistance

Dietary fat is discussed to be critical in the development of non-alcoholic fatty liver disease. Here, we assess the effect of exchanging dietary fat source from butterfat to extra virgin olive oil on the progression of an already existing diet-induced non-alcoholic fatty liver disease in mice. Female C57BL/6J mice were fed a liquid butterfat-, fructose- and cholesterol-rich diet (BFC, 25E% from butterfat) or control diet (C, 12%E from soybean oil) for 13 weeks. In week 9, fat sources of some BFC- and C-fed mice were switched either to 25E% or 12E% olive oil (OFC and CO). Glucose and insulin tolerance tests were performed, and markers of liver damage and glucose metabolism were assessed. After 6 weeks of feeding, BFC-fed mice had developed marked signs of insulin resistance, which progressed to week 12 being not affected by the exchange of fat sources. Liver damage was similar between BFC- and OFC-fed mice. Markers of lipid metabolism and lipid peroxidation in liver and of insulin signaling in liver and muscle were also similarly altered in BFC- and OFC-fed mice. Taken together, our data suggest that exchanging butterfat with extra virgin olive oil has no effect on the progression of non-alcoholic fatty liver disease and glucose tolerance in mice.

The supplementations with 2-hydroxyoleic acid and n-3 polyunsaturated fatty acids revert oxidative stress in various organs of diet-induced obese mice

Obesity and its related diseases have been associated with oxidative stress. Thus, the search for nutritional strategies to ameliorate oxidative stress in obese individuals seems important. We hypothesized that the supplementation with monounsaturated (2-hydroxyoleic acid (2-OHOA)) and with combined n-3 polyunsaturated (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) fatty acids would ameliorate oxidative stress in different organs, including brain, liver, lungs, and kidneys of adult diet-induced obese (DIO) mice. Adult female ICR-CD1 mice were fed a high-fat diet (HFD) for 14 weeks. During the last 6 weeks of HFD feeding, one group of DIO mice received the same HFD, supplemented with 1500 mg of 2-OHOA per kg of HFD and another group with 1500 mg of EPA and 1500 mg of DHA per kg of HFD. At the end of the experiment, several parameters of oxidative stress were assessed. The supplementation with 2-OHOA or with EPA and DHA in DIO mice was able to revert oxidative stress, enhancing the activities of catalase and glutathione reductase, as well as diminishing the activity of xanthine oxidase, the concentration of thiobarbituric acid reactive substances (TBARS) and the ratio between oxidized glutathione and reduced glutathione in several organs. These reached similar values to those of control mice, which were fed a standard diet. These data suggest that supplementation with 2-OHOA and with EPA and DHA could be an effective nutritional intervention to restore an appropriate redox state in DIO mice.

Effect of sulfate group on sulfated polysaccharides-induced improvement of metabolic syndrome and gut microbiota dysbiosis in high fat diet-fed mice

Sulfated polysaccharides were shown to benefit metabolic syndrome (MS) and gut microbiota, but the contribution of sulfate group remains unclear. In this study, sulfated polysaccharides from pacific abalone (AGSP) and its desulfated product (D-AGSP) were prepared, and the contribution of sulfate group was analyzed via in vitro and in vivo models. The result showed that sulfate group had no obvious effect on the reaction of AGSP with RAW 264.7 cells, but it affected the growth properties of gut microbes that able to utilize AGSP. The mice experiment showed that D-AGSP reduced weight gain, fat accumulation and lipid metabolism disorder in HFD-fed mice as well as AGSP, and no differences between them were found. Sequencing analysis showed that sulfate group influenced AGSP-induced alterations of the gut microbiota at higher taxonomic levels, some of which had close correlation with the improvement of physiological index. These results implied that sulfate group may partially determine the activities of polysaccharides via gut microbiota-mediated pathway, but the exact mechanisms need further research.

High-fat but not normal-fat intake of extra virgin olive oil modulates the liver proteome of mice

PURPOSE

The metabolic benefits of the Mediterranean diet have been largely attributed to its olive oil content. Whether the ingested fat amount is relevant to these effects is not clear. We thus compared the effects of high-fat and normal-fat intake of extra-virgin olive oil (EVOO) on the liver proteome.

METHODS

Three groups of mice were fed for 12 weeks with either normal-fat diets containing either soybean oil (control, C) or EVOO (NO) or a high-fat EVOO diet (HO). Body weight and food intake were measured weekly and serum parameters were analyzed. The liver was processed for data-independent acquisition mass spectrometry-based proteomics. The differentially expressed proteins among the groups were submitted to pathway enrichment analysis.

RESULTS

The consumption of HO diet reduced food intake and serum triglycerides, while it preserved body weight gain, adiposity, and glycemia. However, it increased serum cholesterol and liver mass. The proteomic analysis showed 98 altered proteins, which were allocated in 27 significantly enriched pathways. The pathway analysis suggested stimulation of mitochondrial and peroxissomal β-oxidation, and inhibition of lipid synthesis and gluconeogenesis in the HO group. Although the NO group failed to show significant liver proteome alterations, it presented reduced body fat, body weight gain, and serum triglycerides and glucose levels.

CONCLUSION

The data indicate that the intake of the HO diet induced hepatic adjustments, which were partially successful in counteracting the detrimental outcomes of a high-fat feeding. Contrastingly, the NO diet had beneficial effects which were not accompanied by significant modifications on hepatic proteome.

Role of Sirt3 in Differential Sex-Related Responses to a High-Fat Diet in Mice

Metabolic homeostasis is differently regulated in males and females. Little is known about the mitochondrial Sirtuin 3 (Sirt3) protein in the context of sex-related differences in the development of metabolic dysregulation. To test our hypothesis that the role of Sirt3 in response to a high-fat diet (HFD) is sex-related, we measured metabolic, antioxidative, and mitochondrial parameters in the liver of Sirt3 wild-type (WT) and knockout (KO) mice of both sexes fed with a standard or HFD for ten weeks. We found that the combined effect of Sirt3 and an HFD was evident in more parameters in males (lipid content, glucose uptake, pparγ, cyp2e1, cyp4a14, Nrf2, MnSOD activity) than in females (protein damage and mitochondrial respiration), pointing towards a higher reliance of males on the effect of Sirt3 against HFD-induced metabolic dysregulation. The male-specific effects of an HFD also include reduced Sirt3 expression in WT and alleviated lipid accumulation and reduced glucose uptake in KO mice. In females, with a generally higher expression of genes involved in lipid homeostasis, either the HFD or Sirt3 depletion compromised mitochondrial respiration and increased protein oxidative damage. This work presents new insights into sex-related differences in the various physiological parameters with respect to nutritive excess and Sirt3.

Extra Virgin Olive Oil Polyphenols: Modulation of Cellular Pathways Related to Oxidant Species and Inflammation in Aging

The olive-oil-centered Mediterranean diet has been associated with extended life expectancy and a reduction in the risk of age-related degenerative diseases. Extra virgin olive oil (EVOO) itself has been proposed to promote a "successful aging", being able to virtually modulate all the features of the aging process, because of its great monounsaturated fatty acids content and its minor bioactive compounds, the polyphenols above all. Polyphenols are mostly antioxidant and anti-inflammatory compounds, able to modulate abnormal cellular signaling induced by pro-inflammatory stimuli and oxidative stress, as that related to NF-E2-related factor 2 (Nrf-2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), which have been identified as important modulators of age-related disorders and aging itself. This review summarizes existing literature about the interaction between EVOO polyphenols and NF-κB and Nrf-2 signaling pathways. Reported studies show the ability of EVOO phenolics, mainly hydroxytyrosol and tyrosol, to activate Nrf-2 signaling, inducing a cellular defense response and to prevent NF-κB activation, thus suppressing the induction of a pro-inflammatory phenotype. Literature data, although not exhaustive, indicate as a whole that EVOO polyphenols may significantly help to modulate the aging process, so tightly connected to oxidative stress and chronic inflammation.

Iron-induced derangement in hepatic Δ-5 and Δ-6 desaturation capacity and fatty acid profile leading to steatosis: Impact on extrahepatic tissues and prevention by antioxidant-rich extra virgin olive oil

The administration of iron induces liver oxidative stress and depletion of long-chain polyunsaturated fatty acids (LCPUFAs), n-6/n-3 LCPUFA ratio enhancement and fat accumulation, which may be prevented by antioxidant-rich extra virgin olive oil (AR-EVOO) supplementation. Male Wistar rats were subjected to a control diet (50 mg iron/kg diet) or iron-rich diet (IRD; 200 mg/kg diet) with alternate AR-EVOO for 21 days. Liver fatty acid (FA) analysis was performed by gas-liquid chromatography (GLC) after lipid extraction and fractionation, besides Δ-5 desaturase (Δ-5 D) and Δ6-D mRNA expression (qPCR) and activity (GLC) measurements. The IRD significantly (p < 0.05) increased hepatic total fat, triacylglycerols, free FA contents and serum transaminases levels, with diminution in those of n-6 and n-3 LCPUFAs, higher n-6/n-3 ratios, lower unsaturation index and Δ5-D and Δ6-D activities, whereas the mRNA expression of both desaturases was enhanced over control values, changes that were prevented by concomitant AR-EVOO supplementation. N-6 and n-3 LCPUFAs were also decreased by IRD in extrahepatic tissues and normalized by AR-EVOO. In conclusion, AR-EVOO supplementation prevents IRD-induced changes in parameters related to liver FA metabolism and steatosis, an effect that may have a significant impact in the treatment of iron-related pathologies or metabolic disorders such as non-alcoholic fatty liver disease.

Lactobacillus casei-fermented blueberry pomace augments sIgA production in high-fat diet mice by improving intestinal microbiota

Intestinal secretory immunoglobulin A (sIgA)-improving function of Lactobacillus casei-fermented blueberry pomace (FBP) was investigated in this study.

Oxygenic metabolism in nutritional obesity induced by olive oil. The influence of vitamin C

Obesity is a medical and sociological problem of great importance due to the high percentage of people affected and the important health consequences that it involves. Most cases of obesity are related to an inadequate diet, rich in fats, which could lead to changes in the patient's oxygenic metabolism. That is why this study has been proposed to evaluate how some aspects of oxygenic metabolism are affected in a nutritional experimental model, with a controlled hyperlipidic liquid diet based on olive oil, and the effect of the antioxidant vitamin C on these conditions. Wistar rats were divided into four groups which received a control and hyperlipidic liquid diet for 30 days, with or without a vitamin C supplement (CO, COC, HO and HOC). First of all the body and fat tissue development was measured in the four groups. Our results showed that the excessive intake of nutritional and healthy fat such as olive oil did not prevent the appearance of obesity and the supplementation with vitamin C did not have a protective effect on body and fat development. The study of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in total liver, liver cytosol, abdominal white fat, brown fat and blood cells showed that vitamin C could have different selectivities and affinities for different enzymes and compartments/tissues of the body. Finally, the effect of vitamin C on various metabolic parameters (glucose, pyruvate, lactate, LDH, ATP, acetoacetate and beta-hydroxybutyrate) provided positive protection against oxidative stress especially under hyperlipidic conditions. All things considered, the present study concludes that vitamin C treatment could protect Wistar rats from the oxidative stress impairment induced by obesity generated by an excessive intake of fats.

Role of anti-inflammatory interventions in high-fat-diet-induced obesity

Lipotoxicity is defined as deposition of excess fat associated with an inflammatory response. Metabolomic analysis of fatty acids (FAs) can be a marker of silent inflammation. ω3-Enriched diet, celecoxib, and safranal may have a protective anti-inflammatory role. In this work, total FAs extracted from red blood cells and arachidonic acid-to-eicosapentaenoic acid (AA-to-EPA) ratios were assessed using GC-MS assay in single-ion monitoring mode. The study was conducted on 64 male rats divided into eight groups: I, controls; II, rats received high-fat diet (HFD), III, rats received ω-6-enriched HFD; IV, rats received ω-3-enriched HFD; V, rats received celecoxib with HFD; VI, rats received safranal with HFD; VII and VIII, rats received celecoxib and safranal with ω-3 HFD, respectively. GC-MS Gas chromatography Mass spectrometry was performed for analysis of fatty acid methyl ester. Enzyme-linked immunosorbent assay was used to analyze serum interleukin-6 (IL-6) and transforming growth factor-beta 1 (TGF-β1) concentrations. A statistically significant decrease of AA-to-EPA ratio was observed in group VII when compared with the groups receiving HFDs. This group also showed the lowest serum IL-6 level and highest TGF-β1 level. In conclusion, ω3-enriched diet along with drugs (e.g. celecoxib) and herbal medications (e.g. safranal) may have an anti-inflammatory effect in lipotoxicity. GC-MS with single-ion monitoring is valid for the analysis of FAs.

Docosahexaenoic acid and hydroxytyrosol co-administration fully prevents liver steatosis and related parameters in mice subjected to high-fat diet: A molecular approach

Attenuation of high-fat diet (HFD)-induced liver steatosis is accomplished by different nutritional interventions. Considering that the n-3 PUFA docosahexaenoic acid (DHA) modulates lipid metabolism and the antioxidant hydroxytyrosol (HT) diminishes oxidative stress underlying fatty liver, it is hypothesized that HFD-induced steatosis is suppressed by DHA and HT co-administration. Male C57BL/6J mice were fed a control diet (CD; 10% fat, 20% protein, 70% carbohydrates) or a HFD (60% fat, 20% protein, 20% carbohydrates) for 12 weeks, without and with supplementation of DHA (50 mg/kg/day), HT (5 mg/kg/day) or both. The combined DHA + HT protocol fully prevented liver steatosis and the concomitant pro-inflammatory state induced by HFD, with suppression of lipogenic and oxidative stress signaling, recovery of fatty acid oxidation capacity and enhancement in resolvin availability affording higher inflammation resolution capability. Abrogation of HFD-induced hepatic steatosis by DHA and HT co-administration represents a crucial therapeutic strategy eluding disease progression into stages lacking efficacious handling at present time.

Heart Histopathology and Mitochondrial Ultrastructure in Aged Rats Fed for 24 Months on Different Unsaturated Fats (Virgin Olive Oil, Sunflower Oil or Fish Oil) and Affected by Different Longevity

Diet plays a decisive role in heart physiology, with lipids having especial importance in pathology prevention and development. This study aimed to investigate how dietary lipids varying in lipid profile (virgin olive oil, sunflower oil or fish oil) affected the heart of rats during aging. Heart histopathology, mitochondrial morphometry, and oxidative status were assessed. Typical histopathological features associated with aging, such as valvular lesions, endomyocardical hyperplasia, or papillary muscle calcification, were found at a low extent in all the experimental groups. The most relevant finding was that inflammation registered by fish oil group was lower compared to the other treatments. At the ultrastructural level, heart mitochondrial area, perimeter, and aspect ratio were higher in fish oil-fed rats than in those fed on sunflower oil. Concerning oxidative stress markers, there were differences only in coenzyme Q levels and catalase activity, lower in sunflower oil-fed animals compared with those fed on fish oil. In summary, dietary intake for a long period on dietary fats with different fatty acids profile led to differences in some aspects associated with the aging process at the heart. Fish oil seems to be the fat most protective of heart during aging.

High-fat diet induces mouse liver steatosis with a concomitant decline in energy metabolism: attenuation by eicosapentaenoic acid (EPA) or hydroxytyrosol (HT) supplementation and the additive effects upon EPA and HT co-administration

High-fat-diet (HFD) feeding is associated with liver oxidative stress (OS), n-3 long-chain polyunsaturated fatty acid (n-3 LCPUFA) depletion, hepatic steatosis and mitochondrial dysfunction. Our hypothesis is that the HFD-induced liver injury can be attenuated by the combined supplementation of n-3 LCPUFA eicosapentaenoic acid (EPA) and the antioxidant hydroxytyrosol (HT). The C57BL/6J mice were administered an HFD (60% fat, 20% protein, 20% carbohydrates) or control diet (CD; 10% fat, 20% protein, 70% carbohydrates), with or without EPA (50 mg kg-1 day-1), HT (5 mg kg-1 day-1), or EPA + HT (50 and 5 mg kg-1 day-1, respectively) for 12 weeks. We measured the body and liver weights and dietary and energy intakes along with liver histology, FA composition, steatosis score and associated transcription factors, mitochondrial functions and metabolic factors related to energy sensing through the AMP-activated protein kinase (AMPK) and PPAR-γ coactivator-1α (PGC-1α) cascade. It was found that the HFD significantly induced liver steatosis, with a 66% depletion of n-3 LCPUFAs and a 100% increase in n-6/n-3 LCPUFA ratio as compared to the case of CD (p < 0.05). These changes were concomitant with (i) a 95% higher lipogenic and 70% lower FA oxidation signaling, (ii) a 40% diminution in mitochondrial respiratory capacity and (iii) a 56% lower ATP content. HFD-induced liver steatosis was also associated with (iv) a depressed mRNA expression of AMPK-PGC-1α signaling components, nuclear respiratory factor-2 (NRF-2) and β-ATP synthase. These HFD effects were significantly attenuated by the combined EPA + HT supplementation in an additive manner. These results suggested that EPA and HT co-administration partly prevented HFD-induced liver steatosis, thus strengthening the importance of combined interventions in hepatoprotection in non-alcoholic fatty liver disease.

Olive oil antioxidants and non-alcoholic fatty liver disease

Introduction: Non-alcoholic fatty liver disease (NAFLD) is estimated to affect 25% of adult people worldwide. Nowadays, there is no definite treatment for NAFLD. International guidelines define an approach based on lifestyle changes, included a health alimentary regimen. The Mediterranean diet (MD) represents the gold standard in preventive medicine, probably due to the harmonic combination of many elements with antioxidant and anti-inflammatory properties. Its prescription is also recommended in patients with NAFLD. Olive oil, as part of MD, is associated with benefits on human health especially regarding the cardiovascular system, obesity, diabetes and related metabolic disorders. Areas covered: An overview of the beneficial effects of olive oil in the prevention and treatment of NAFLD is given. Expert opinion: A large body of evidence emphasizes that olive oil, used as primary source of fat in MD, may play a crucial role in the health benefits of NAFLD patients. However, there are still scarce clinical data that evaluate the direct effect of olive oil in human with NAFLD.

Effects of Olive Leaf Extract on Prevention of Molecular, Histopathological, and Enzymatic Changes in Chicken Carbon Tetrachloride-Induced Liver Damage

BACKGROUND

Today, the use of additives such as antibiotics and growth hormones that increase production efficiency in breeding broiler chickens has become inevitable. However, the use of such additives and antibiotics associated with side effects such as liver damage. Oxidative stress occurs due to an imbalance between oxidants and antioxidants. Studies have shown that olive leaves have an antioxidant effect on free radicals. This study was to evaluate the possible effect of olive leaf extract on carbon tetrachloride (CCL4)-induced liver damage (molecular and tissue) and changes of enzymes in chickens.

MATERIALS AND METHODS

A total of 50 chickens were used and classified into5 groups. Treatment groups received 0.5, 1, and 1.5 mg/kg of the olive leaf extract from day 21 of the experiment. Two control groups-healthy and poisoned-did not receive any extract. On the day 35 of the experiment, 1cc of CCL4 was dissolved with olive oil and injected intraperitoneally into the experimental and poisoned control groups. Blood and liver tissue sampling were performed.

RESULTS

The histopathology results showed that at high doses of olive leaf extract, the cells and vessels were regularly curable, and sinusoids were healthy. The expression of B-cell lymphoma 2 (BCL2) increased, and that of BH3 interacting domain death agonist (BID )decreased. Enzymatic tests, including serum glutamic-oxaloacetic transaminase, serum glutamic-pyruvic transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, showed a reduction in BID expression in the experimental group compared with the control group(P<0.005).

CONCLUSION

We concluded that olive leaf extract boosts the BCL2 -an antiapoptotic gene-and reduces BID -an apoptosis gene-in the liver of chicken. It prevents the liver cells from disintegrating and destroys sinusoids and liver blood vessels. The high doses of the olive leaf extract caused liver resistance to CCL4 toxicity in chicken.

Combined administration of docosahexaenoic acid and thyroid hormone synergistically enhances rat liver levels of resolvins RvD1 and RvD2

Supplementation with omega-3 fatty acids or thyroid hormone (T₃) exhibit negative effects on inflammatory reactions in experimental animals. The aim of this work was to assess the hypothesis that docosahexaenoic acid (DHA) plus T₃ co-administration enhances liver resolvin (Rv) levels as inflammation resolution mediators. Combined DHA (daily doses of 300 mg/kg for 3 consecutive days)-T₃ (0.05 mg/kg at the fourth day) administration significantly increased the content of hepatic RvD1 and RvD2, without changes in that of RvE1 and RvE2, an effect that exhibits synergy when compared to the separate DHA and T₃ treatments. Under these conditions, liver DHA levels increased by DHA administration were diminished when combined with T₃ (p < 0.05), suggesting enhancement in resolvin D biosynthesis in extrahepatic tissues. It is concluded that co-administration of DHA and T₃ rises the capacity of the liver for inflammation resolution by augmenting RvD1(2) availability, which represents an important protocol in hepatoprotection in the clinical setting.

Molecular mechanisms related to the hepatoprotective effects of antioxidant-rich extra virgin olive oil supplementation in rats subjected to short-term iron administration

Enhanced iron levels in liver are associated with oxidative stress development and damage with increased fat accumulation. The aim of this work was to assess the hypothesis that antioxidant-rich extra virgin olive oil (AR-EVOO) counteracts iron-rich diet (IRD)-induced oxidative stress hindering hepatic steatosis. Male Wistar rats were fed and IRD (200 mg iron/kg diet) versus a control diet (CD; 50 mg iron/kg diet) with alternate AR-EVOO supplementation (100 mg/day) for 21 days. IRD induced liver steatosis and oxidative stress (higher levels of protein oxidation and lipid peroxidation with glutathione depletion), mitochondrial dysfunction (decreased citrate synthase and complex I and II activities) and loss of polyunsaturated fatty acids (PUFAs), with a drastic enhancement in the sterol regulatory element-binding protein-1c (SREBP-1c)/peroxisome proliferator-activated receptor-α (PPAR-α) ratio upregulating the expression of lipogenic enzymes (acetyl-CoA carboxylase, fatty acid (FA) synthase and stearoyl desaturase 2) and downregulating those involved in FA oxidation (carnitine palmitoyl transferase and acyl-CoA oxidase) over values in the CD group. IRD also upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and its target genes. AR-EVOO supplementation alone did not modify the studied parameters, however, IRD combined with AR-EVOO administration returned IRD-induced changes to baseline levels of the CD group. It is concluded that IRD-induced non-alcoholic fatty liver disease (NAFLD) is prevented by AR-EVOO supplementation, which might be related to the protective effects of its components such as hydroxytyrosol, oleic acid, tocopherols and/or PUFAs, thus representing a suitable anti-steatotic strategy to avoid progression into more severe stages of the disease, underlying NAFLD associated with iron overloading pathologies or obesity.

Reduction of high-fat diet-induced liver proinflammatory state by eicosapentaenoic acid plus hydroxytyrosol supplementation: involvement of resolvins RvE1/2 and RvD1/2

High-fat diet (HFD)-fed mice show obesity with development of liver steatosis and a proinflammatory state without establishing an inflammatory reaction. The aim of this work was to assess the hypothesis that eicosapentaenoic acid (EPA) plus hydroxytyrosol (HT) supplementation prevents the inflammatory reaction through enhancement in the hepatic resolvin content in HFD-fed mice. Male C57BL/6J mice were fed an HFD or a control diet and supplemented with EPA (50 mg/kg/day) and HT (5 mg/kg/day) or their respective vehicles for 12 weeks. Measurements include liver levels of EPA, DHA and palmitate (gas chromatography), liver resolvins and triglyceride (TG) and serum aspartate transaminase (AST) (specific kits) and hepatic and serum inflammatory markers (quantitative polymerase chain reaction and enzyme-linked immunosorbent assay). Compared to CD, HFD induced body weight gain, liver steatosis and TG accumulation, with up-regulation of proinflammatory markers in the absence of histological inflammation or serum AST changes; these results were accompanied by higher hepatic levels of resolvins RvE1, RvE2, RvD1 and RvD2, with decreases in EPA and DHA contents. EPA+HT supplementation in HFD feeding synergistically reduced the steatosis score over individual treatments and increased the hepatic levels of EPA, DHA and resolvins, with attenuation of proinflammatory markers. Lack of progression of HFD-induced proinflammatory state into overt inflammation is associated with resolvin up-regulation, which is further increased by EPA+HT supplementation eliciting steatosis attenuation. These findings point to the importance of combined protocols in hepatoprotection due to the involvement of cross-talk mechanisms, which increase effectiveness and diminish dosages, avoiding undesirable effects.

Effects of Olive Oil supplementation on Sodium Arsenate-induced Hepatotoxicity in Mice

Background:

Sodium arsenate (As), a toxic substance with induced oxidative stress, lead to hepatotoxicity. Olive oil (OO) with antioxidant property has protective effect on toxicity. The aim of this study was to investigate protective effect of OO on sodium As-induced hepatotoxicity in mice.

Subjects and Methods:

In this experimental study, 32 adult male BALB/c mice were divided randomly into four groups: control group (received only normal saline, the same volume as other groups), OO (0.4 mL/day, gavage), sodium As (15 mg/kg, gavage), and OO + sodium As (received OO 1 h before sodium As). Drugs were given for 30 consecutive days. After the last receipt of the drugs, oxidative stress parameters [malondialdehyde (MDA), glutathione (GSH)] in tissue, liver function parameters [alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP)] in serum, ferric reducing ability of plasma (FRAP) in plasma, and histopathological assays were performed.

Results:

Sodium As induced hepatic injury as indicated by significant increase in AST, ALT, ALP, and LDH in serum and pathologic evidences. It also induces hepatic oxidative stress biomarkers as indicated by significant increase in levels of MDA and significant decrease in FRAP and GSH concentration. OO administration significantly improved oxidative stress parameters, histopathological changes, and enzymatic markers of liver injury.

Conclusions:

It was concluded that antioxidant activity of OO has hepatoprotective effect on As-induced hepatic injury.

Attenuation of High-Fat Diet-Induced Rat Liver Oxidative Stress and Steatosis by Combined Hydroxytyrosol- (HT-) Eicosapentaenoic Acid Supplementation Mainly Relies on HT

Pharmacological therapy for nonalcoholic fatty liver disease (NAFLD) is not approved at the present time. For this purpose, the effect of combined eicosapentaenoic acid (EPA; 50 mg/kg/day) modulating hepatic lipid metabolism and hydroxytyrosol (HT; 5 mg/kg/day) exerting antioxidant actions was evaluated on hepatic steatosis and oxidative stress induced by a high-fat diet (HFD; 60% fat, 20% protein, and 20% carbohydrates) compared to a control diet (CD; 10% fat, 20% protein, and 70% carbohydrates) in mice fed for 12 weeks. HFD-induced liver steatosis (i) was reduced by 32% by EPA, without changes in oxidative stress-related parameters and mild recovery of Nrf2 functioning affording antioxidation and (ii) was decreased by 42% by HT, concomitantly with total regain of the glutathione status diminished by HFD, 42% to 59% recovery of lipid peroxidation and protein oxidation enhanced by HFD, and regain of Nrf2 functioning, whereas (iii) combined EPA + HT supplementation elicited 74% reduction in liver steatosis, with total recovery of the antioxidant potential in a similar manner than HT. It is concluded that combined HT + EPA drastically decreases NAFLD development, an effect that shows additivity in HT and EPA effects that mainly relies on HT, strengthening the impact of oxidative stress as a central mechanism underlying liver steatosis in obesity.

The Impact of Maternal Diet during Pregnancy and Lactation on the Fatty Acid Composition of Erythrocytes and Breast Milk of Chilean Women

Maternal diet during pregnancy is relevant for fatty acid supply during fetal life and lactation. Arachidonic (AA) and docosahexaenoic (DHA) acids are also relevant for the normal growth and development of brain and visual system. AA and DHA provided by the mother to the fetus and infant are directly associated with maternal dietary intake and body stores. Our aim was to evaluate the impact of maternal diet, specially referring to the quality of fatty acid intake, in a sample of Chilean women during last stage of pregnancy and across the lactation period. Fifty healthy pregnant women (age range 20–33 years) were studied from the 6th month of pregnancy and followed until 6th month of lactation period. Diet characteristics were evaluated through food frequency questionnaires. Fatty acids composition of erythrocyte phospholipids and breast milk samples was assessed by gas-liquid chromatography. Overall, women had high saturated fatty acids intake with sufficient intake of mono- and polyunsaturated fatty acids (PUFA). Diet was high in n-6 PUFA and low in n-3 PUFA (mainly DHA), with imbalanced n-6/n-3 PUFA ratio. Erythrocytes and breast milk DHA concentration was significantly reduced during lactation compared to pregnancy, a pattern not observed for AA. We concluded that is necessary to increase the intake of n-3 PUFA during pregnancy and lactation by improving the quality of consumed foods with particular emphasis on its DHA content.

Pharma-Nutritional Properties of Olive Oil Phenols. Transfer of New Findings to Human Nutrition

The Mediterranean diet has been long associated with improved cardiovascular prognosis, chemoprevention, and lower incidence of neurodegeneration. Of the multiple components of this diet, olive oil stands out because its use has historically been limited to the Mediterranean basin. The health benefits of olive oil and some of its components are being rapidly decoded. In this paper we review the most recent pharma-nutritional investigations on olive oil biophenols and their health effects, chiefly focusing on recent findings that elucidate their molecular mechanisms of action.

Chinese olive extract ameliorates hepatic lipid accumulation in vitro and in vivo by regulating lipid metabolism

Chinese olive contains plenty of polyphenols, which possess a wide range of biological actions. In this study, we aimed to investigate the role of the ethyl acetate fraction of Chinese olive fruit extract (CO-EtOAc) in the modulation of lipid accumulation in vitro and in vivo. In cellular studies, CO-EtOAc attenuated oleic acid-induced lipid accumulation; we then elucidated the molecular mechanisms of CO-EtOAc in FL83B mouse hepatocytes. CO-EtOAc suppressed the mRNA levels of fatty acid transporter genes (CD36 and FABP) and lipogenesis genes (SREBP-1c, FAS, and ACC1), but upregulated genes that govern lipolysis (HSL) and lipid oxidation (PPARα, CPT-1, and ACOX). Moreover, CO-EtOAc increased the protein expression of phosphorylated AMPK, ACC1, CPT-1, and PPARα, but downregulated the expression of mature SREBP-1c and FAS. AMPK plays an essential role in CO-EtOAc-mediated amelioration of lipid accumulation. Furthermore, we confirmed that CO-EtOAc significantly inhibited body weight gain, epididymal adipose tissue weight, and hepatic lipid accumulation via regulation of the expression of fatty acid transporter, lipogenesis, and fatty acid oxidation genes and proteins in C57BL/6 mice fed a 60% high-fat diet. Therefore, Chinese olive fruits may have the potential to improve the metabolic abnormalities associated with fatty liver under high fat challenge.