Effects of a High-Fat Diet and Docosahexaenoic Acid during Pregnancy on Fatty Acid Composition in the Fetal Livers of Mice

A high-fat diet (HFD) during pregnancy promotes fat accumulation and reduces docosahexaenoic acid (DHA) levels in the liver of the offspring at postnatal ages, which can depend on fetal sex. However, the prenatal mechanisms behind these associations are still unclear. Thus, we analyzed if an HFD alters DHA content and the expression of molecules related to fatty acid (FA) metabolism in the fetal liver. Female C57BL/6 mice were fed a control diet or HFD for 4-6 weeks before pregnancy until the gestational day (GD) 17.5. A subgroup of each diet received DHA (100 mg/Kg) orally from GD 6.5 until 16.5. On GD 17.5, maternal livers, placentas, and livers from male and female fetuses were collected for FA profiling with gas-chromatography and gene expression of molecules related to FA metabolism using qPCR. PPAR-α protein expression was evaluated using Western blot. The gene expression of placental FA transporters was also assessed. An HFD increased eicosapentaenoic acid (EPA) and decreased DHA levels and protein expression of PPAR-α in the fetal livers of both sexes. DHA increased the gene expression of Ppara, Cpt1, and Acsl1 in the livers of female fetuses. Therefore, an HFD reduces DHA levels and PPAR-α, a master regulator of gene expression, in the fetal liver. In turn, the livers of female fetuses seem to be more sensitive to DHA action.

Linoleic and arachidonic fatty acids and their potential relationship with inflammation, pregnancy, and fetal development

BACKGROUND

A healthy maternal diet must consider an appropriate supply of long-chain polyunsaturated fatty acids (LCPUFAs) precursors to ensure adequate growth and development of the fetus. In this regard, n-6 PUFAs, predominantly linoleic (C18:2 n-6, LA) and arachidonic acid (C20:4 n-6), have a central role in the development of the central nervous system because they are part of the membrane structure and participate in the metabolism and signal transduction of cells. Nevertheless, they can also be transformed into inflammatory metabolites promoting the pathogenesis of cardiovascular diseases, cancer, and autoimmune or inflammatory conditions. In modern westernized societies, there is a high dietary consumption of foods rich in n-6 PUFAs which could have detrimental consequences for the fetus and neonate due to excessive exposure to these fatty acids (FAs).

OBJECTIVE

To summarize the evidence of maternal, placental, and fetal alterations that an excessive intake of n-6 polyunsaturated FAs (PUFAs), LA, and AA), could produce during pregnancy.

METHODS

A thorough review of the literature regarding the effects of n-6 PUFAs during pregnancy and lactation including in vivo and in vitro models, was carried out using the PubMed database from the National Library of Medicine-National Institutes of Health.

RESULTS

An elevated intake of n-6 PUFA, specifically LA, during pregnancy influences children's motor, cognitive, and verbal development during infancy and early childhood. Similarly, they could harm the placenta and the development of other fetal organs such as the fat tissue, liver, and cardiovascular system.

CONCLUSION

Maternal diet, specifically LA intake, could have significant repercussions on fetal development and long-term consequences in the offspring, including the possibility of future metabolic and mental diseases. It would be necessary to focus on the prevention of these alterations through timely dietary interventions in the target population.

Association between maternal obesity, essential fatty acids and biomarkers of fetal liver function

Maternal obesity and the imbalance in linoleic acid (C18:2 n-6, LA) and alpha-linolenic acid (C18:3 n-3, ALA) levels are related with hepatic disturbances in the offspring. However, whether these alterations are present during fetal life is not well understood. Obese and normal weight pregnant women were recruited to determine fatty acids (FAs) consumption, FAs profile (in maternal erythrocytes, placenta and neonatal very low-density lipoproteins VLDL) and biomarkers of fetal liver function, such as gamma-glutamyl transferase (GGT), alpha-fetoprotein (AFP) and albumin, in umbilical cord blood. Stearic acid (C18:0, ST) was lower, and total n-3 FAs tended to be lower in umbilical cord VLDLs of obese women compared to controls. Independently of maternal obesity, GGT levels in umbilical cord blood was positively correlated with the LA content and negatively correlated with the ALA content in maternal erythrocytes. We conclude that maternal obesity and its imbalance of LA and ALA are associated with changes in biomarkers of fetal liver function.

Carbohydrate-Derived Polytriazole Nanoparticles Enhance the Anti-Inflammatory Activity of Cilostazol

Poly(amide-triazole) and poly(ester-triazole) synthesized from d-galactose as a renewable resource were applied for the synthesis of nanoparticles (NPs) by the emulsification/solvent evaporation method. The NPs were characterized as stable, spherical particles, and none of their components, including the stabilizer poly(vinyl alcohol), were cytotoxic for normal rat kidney cells. These NPs proved to be useful for the efficient encapsulation of cilostazol (CLZ), an antiplatelet and vasodilator drug currently used for the treatment of intermittent claudication, which is associated with undesired side-effects. In this context, the nanoencapsulation of CLZ was expected to improve its therapeutic administration. The carbohydrate-derived polymeric NPs were designed taking into account that the triazole rings of the polymer backbone could have attractive interactions with the tetrazole ring of CLZ. The activity of the nanoencapsulated CLZ was measured using a matrix metalloproteinase model in a lipopolysaccharide-induced inflammation system. Interestingly, the encapsulated drug exhibited enhanced anti-inflammatory activity in comparison with the free drug. The results are very promising since the stable, noncytotoxic NP systems efficiently reduced the inflammation response at low CLZ doses. In summary, the NPs were obtained through an innovative methodology that combines a carbohydrate-derived synthetic polymer, designed to interact with the drug, ease of preparation, adequate biological performance, and environmentally friendly production.

Beneficial effects of dietary polyphenols in the prevention and treatment of NAFLD: cell-signaling pathways underlying health effects

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic accretion of triacylglycerides in the absence of alcohol intake that may progress to steatohepatitis, fibrosis and cirrhosis, becoming the main cause of chronic liver disease. This article discusses recent data concerning the use of dietary polyphenols in the prevention and treatment of NAFLD in vitro, in vivo, and in clinical trials.

METHODS

Study searches were performed using the PubMed database from the National Library of Medicine-National Institutes of Health.

RESULTS

Polyphenols exert beneficial effects in NAFLD, with positive outcomes being related to body weight gain, insulin resistance, liver fat accumulation, oxidative stress, pro-inflammatory status, mitochondrial dysfunction and ER stress. Data reported for hydroxytyrosol suggest that the activation of the hepatic PPAR-α-FGF21-AMPK-PGC-1α signaling cascade is associated with fatty acid oxidation enhancement, de novo lipogenesis diminution and recovery of mitochondrial function, a contention that is supported by the actions of several polyphenols on specific components of this signaling pathway. Besides, polyphenols downregulate NF-κB, suppressing the pro-inflammatory state developed in NAFLD and upregulate liver Nrf2, increasing the cellular antioxidant potential. The latter feature of polyphenols is contributed by chelation of pro-oxidant trace elements, reduction of free radicals to stable forms and inhibition of free radical generating systems.

CONCLUSION

Polyphenols are relevant bioactive compounds in terms of prevention and treatment of NAFLD, which exhibit low bioavailability and instability in biological systems that could limit their health effects. These drawbacks reinforce the necessity of further studies to improve the efficacy of polyphenol formulations for human interventions.

AB0374 CHARACTERISTICS OF A GIANT CELL ARTERITIS COHORT IN LATINOAMERICA

Background:

Giant cell arteritis (GCA) is a large vessel vasculitis (LVV) that affects mostly the elderly (1). Temporal artery biopsy (TAB) has been defined as the gold standard, although this has come to question (3). EULAR guidelines recommended non-invasive imaging techniques such as the temporal artery Doppler ultrasound to aid in LVV diagnosis (2). The characterization of GCA in Latin American countries, and specifically in Colombia, is scarce.

Objectives:

To perform a clinical, demographical, histopathological, and radiological characterization of

Colombian GCA patients.

Methods:

Retrospective data from GCA patients at two teaching hospitals in Medellín, Colombia, was collected. A bioethics committee previously approved the research protocol. Inclusion criteria: diagnosis of GCA, based on clinical characteristics or imaging/biopsy findings. Exclusion criteria: HIV diagnosis, paraneoplastic large vessel vasculitis. Clinical, radiological, and histopathological variables were selected based on the clinicians’ expertise and the 2018 EULAR recommendations for a core data set to support observational research and clinical care in giant cell arteritis (3). The data were analyzed in SPSS v22.0 (IBM, USA).

Results:

Twenty-two patients were collected. Demographical and clinical characteristics are summarized in Table 1. Most patients were women (68.1%), with a mean age of 71.8 years, mean duration of symptoms of 5.3 months. In the cranial form of the disease, the most common symptoms were headache and jaw claudication (95% and 68%). Six patients experienced visual loss: complete unilateral visual loss in two, partial unilateral in two, complete bilateral in one, and partial bilateral in one patient.

Sixteen patients (72.7%) underwent TAB; the most common finding was mononuclear infiltrate and internal elastic fragmentation in 43.7% of the biopsies. Giant cells were observed in 6 biopsies (37.5%). Doppler ultrasound was performed in 19 patients (86.35%), finding intima-media thickening and the halo sign t in 7 patients (36.8%).

Table 1.

Demographical and clinical characteristics

Characteristicn = 22Mean age (years SD)71.8 (10.6)Female sex n (%)15 (68.1%)Mean symptoms duration (months ± SD)5.3 ± 6.8Mestizo n (%)20 (90%)Headache n (%)21 (95.4%)Jaw claudication n (%)15 (68.1%)Weight loss n (%)13 (59%)Scalp sensitivity n (%)11 (50%)Fever n (%)8 (36.3%)Presence of polymyalgia rheumatica n (%)7 (31.8%)Visual loss n (%)6 (27.2%)Amaurosis fugax n (%)1 (4.5%)Glucocorticoids n (%)22 (100%)Pulse n (%)8 (36.3%)Mean dose (mg ± SD)47.1 ± 16.7Methotrexate n (%)17 (77.7%)Azathioprine n (%)2 (9%)Tocilizumab n (%)1 (4.5%)

Conclusion:

In this GCA cohort, the main phenotype was cranial GCA, with 95% of the patients presenting with headache. The most common imaging study performed was Doppler ultrasound of temporal arteries, with intima-media thickening and halo sign being the most common findings. The mainstay of treatment was glucocorticoids with methotrexate as a sparing agent. To our knowledge, this study is the first to perform a specific characterization of GCA patients in the Colombian population, and it can represent the foundation of further research for these patients.

References:

[1]Lazarewicz K, Watson P. Giant cell arteritis. BMJ. 2019 May 30;365:l1964.

[2]Dejaco C, Ramiro S, Duftner C, Besson FL, Bley TA, Blockmans D, et al. EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice. Ann Rheum Dis. 2018 May;77(5):636–43.

[3]Ehlers L, Askling J, Bijlsma HWJ, Cid MC, Cutolo M, Dasgupta B, et al. 2018 EULAR recommendations for a core data set to support observational research and clinical care in giant cell arteritis. Ann Rheum Dis. 2019;78(9):1160–6.

Disclosure of Interests:

None declared

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.

Exploring Anhedonia in Kennelled Dogs: Could Coping Styles Affect Hedonic Preferences for Sweet and Umami Flavours?

Simple Summary

Kennelled dogs are susceptible to suffer chronic stress when social interactions with conspecifics and spatial needs are long-term restricted. Chronic stress may affect pleasure perception of food and solutions in dogs as observed in several animals, a phenomenon known as anhedonia. However, little information exists on how different coping styles could prevent the onset of anhedonia. Fourteen kennelled Beagle dogs were used to study the acceptability and preference for different dilute palatable sucrose and monosodium glutamate (MSG) solutions. Coping style of animals was previously evaluated through a modified human-approach test. This test consisted in assessing whether or not dogs approached an unfamiliar human when a feeding opportunity was presented, classifying them as close dogs (CD; proactive) or distant dogs (DD; reactive) respectively. It was observed that DD presented a lower intake of both sucrose and MSG dilute solutions compared with CD. Moreover, DD exhibited a higher consumption of MSG than CD at the highest concentrations, supporting that their intake depends on solution palatability. Finally, DD did not prefer sucrose or MSG solutions over water at any dilute solution offered. Together, these results suggest that dogs that are categorized as reactive animals could diminish their ability to perceive dilute palatable solutions reflecting depressive-like behaviours such as anhedonia.

Abstract

Kennelled dogs are at risk of suffering chronic stress due to long-term spatial, social and feeding restrictions. Chronic stress may decrease the dogs’ capacity to feel pleasure when facing hedonic experiences, modifying their perception for palatable ingredients. However, different abilities to cope with environmental stressors could prevent the onset of anhedonia. Fourteen kennelled Beagle dogs were used to study the acceptability and preference for different dilute sucrose and monosodium glutamate (MSG) solutions. Coping style of animals was previously evaluated through a human approach test (HAT) and classified as close dogs (CD; proactive) or distant dogs (DD; reactive) according to whether or not they approached an unfamiliar human when a feeding opportunity was presented. Consumption results were analysed taking into account the sucrose/MSG concentrations, HAT (CD or DD), age, and weight of the animals. DD presented a lower intake of sucrose (p = 0.041) and MSG (p = 0.069) solutions compared with CD. However, DD exhibited a higher consumption of MSG than CD at its highest concentrations, supporting that their intake depends on solution palatability. Finally, DD did not prefer sucrose or MSG solutions over water at any dilute solution offered. Together, these results suggest that dogs that are categorized as reactive animals could diminish their ability to perceive dilute palatable solutions, reflecting depressive-like behaviours as anhedonia.

Experimental transmission of Caligus rogercresseyi between two different fish species

Caligus rogercresseyi is the dominant sea louse parasite affecting the salmon and trout industry in southern Chile. This parasite has a wide range of native and endemic fish hosts. The Patagonian blenny Eleginops maclovinus, which is parasitized mostly by the caligid species Lepeophtheirus spp. and C. rogercresseyi, is presumably responsible for the transmission of C. rogercresseyi to salmonids. The aim of this study was to characterize the transmission of parasites between different fish species and parasite cohort development under laboratory conditions. Parasite abundances and intensities were quantified. Transmission of parasites from Patagonian blenny to Atlantic salmon Salmo salar was lower (~9%, mainly corresponding to C. rogercresseyi) than from salmon to Patagonian blenny (14.7-26.9%, where only C. rogercresseyi were observed). This suggests that the transmission of C. rogercresseyi from salmon individuals is higher than the transmission from a native fish. Parasite cohorts developed successfully on both fish species, but apparently under different developmental rates. Water temperature, oxygen, and juvenile abundances were the variables that better explained cohort development success and variation in C. rogercresseyi adult abundances over time.

MON-LB6 Association Between Sex Steroid and Metabolic Parameters in Cord Blood With Placental Fatty Acid Transporter in Obese Pregnant Women

Obesity reduces maternal insulin sensitivity and alters sex steroid serum concentrations. However, it is not clear if these changes are reflected in the fetal circulation. On the other hand, similar to other metabolic tissues, modifications in sex steroid concentrations and metabolic parameters could modify the transport and metabolism of fatty acids (FA) in the placenta increasing their availability for the fetus. Therefore, we aimed to study, in pregnant women with normal-weight and obesity, sex steroid serum concentrations in cord blood and their relationship with the gene expression of FA transporters and of molecules related with FA metabolism in the placenta. We included 26 pregnant women with normal-weight and 26 pregnant women with obesity without pregnancy complications. At term of pregnancy, mixed cord blood and placenta samples were collected and stored at -80°C. Serum concentrations of dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), androstenedione, testosterone, estrone, estradiol, estriol, insulin and TNF-α were measured by RIA or ELISA. Glycemia and lipid profile were also analyzed. In placental samples, the gene expression of MFSD2A, CD36, FABP4, SLC27A4, PPARG, LPL and DGAT were determined by quantitative PCR. No differences were observed in sex steroid concentrations and metabolic parameters between groups. On the other hand, the gene expression of MFSD2A, CD36 and FABP4 were higher in placentas from women with obesity compared to women with normal-weight (P = 0.050, P = 0.037 and P = 0.038, respectively). When distributed according to fetal sex, cholesterol levels were higher in cord blood of women with obesity and female fetuses (P = 0.005), whereas glycemia was lower in women with obesity and male fetuses (P = 0.045). In turn, the gene expression of CD36 and FABP4 were higher (P = 0.024 and P = 0.034, respectively), whereas MFSD2A tended to be higher (P = 0.092) only in placentas from women with obesity and male fetuses. Moreover, in women with obesity and male fetuses, glycemia was positively correlated with MFSD2A (r = 0.650; P = 0.022), and in women with obesity and female fetuses FABP4 was inversely correlated with triglyceride levels (r = -0.580; P = 0.048). In conclusion, these data suggest that modifications in placental steroidogenesis do not affect sex steroid serum concentrations in the fetal circulation. On the other hand, metabolic parameters in cord blood of pregnant women with obesity are associated with an abnormal expression of FA transporters in placental tissue.

Endothelial dysfunction is an early indicator of sepsis and neutrophil degranulation of septic shock in surgical patients

Background

Stratification of the severity of infection is currently based on the Sequential Organ Failure Assessment (SOFA) score, which is difficult to calculate outside the ICU. Biomarkers could help to stratify the severity of infection in surgical patients.

Methods

Levels of ten biomarkers indicating endothelial dysfunction, 22 indicating emergency granulopoiesis, and six denoting neutrophil degranulation were compared in three groups of patients in the first 12 h after diagnosis at three Spanish hospitals.

Results

There were 100 patients with infection, 95 with sepsis and 57 with septic shock. Seven biomarkers indicating endothelial dysfunction (mid‐regional proadrenomedullin (MR‐ProADM), syndecan 1, thrombomodulin, angiopoietin 2, endothelial cell‐specific molecule 1, vascular cell adhesion molecule 1 and E‐selectin) had stronger associations with sepsis than infection alone. MR‐ProADM had the highest odds ratio (OR) in multivariable analysis (OR 11·53, 95 per cent c.i. 4·15 to 32·08; P = 0·006) and the best area under the curve (AUC) for detecting sepsis (0·86, 95 per cent c.i. 0·80 to 0·91; P < 0·001). In a comparison of sepsis with septic shock, two biomarkers of neutrophil degranulation, proteinase 3 (OR 8·09, 1·34 to 48·91; P = 0·028) and lipocalin 2 (OR 6·62, 2·47 to 17·77; P = 0·002), had the strongest association with septic shock, but lipocalin 2 exhibited the highest AUC (0·81, 0·73 to 0·90; P < 0·001).

Conclusion

MR‐ProADM and lipocalin 2 could be alternatives to the SOFA score in the detection of sepsis and septic shock respectively in surgical patients with infection.

Identification and characterization of compounds from Chrysosporium multifidum, a fungus with moderate antimicrobial activity isolated from Hermetia illucens gut microbiota

The gut microbiota of insects is composed of a wide range of microorganisms which produce bioactive compounds that protect their host from pathogenic attack. In the present study, we isolate and identify the fungus Chrysosporium multifidum from the gut of Hermetia illucens larvae. Extract from C. multifidum culture broth supernatant showed moderate activity against a strain of methicillin-resistant Staphylococcus aureus (MRSA). Bioguided isolation of the extract resulted in the characterization of six α-pyrone derivatives (1–6) and one diketopiperazine (7). Of these compounds, 5,6-dihydro-4-methoxy-6-(1-oxopentyl)-2H-pyran-2-one (4) showed the greatest activity (IC₅₀ = 11.4 ± 0.7 μg/mL and MIC = 62.5 μg/mL) against MRSA.

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.

Effect of female sex hormones on the developmental cycle of Chlamydia abortus compared to a penicillin-induced model of persistent infection

Background

Chlamydia abortus, an obligate intracellular pathogen with an affinity for placenta, causes reproductive failure. In non-pregnant animals, an initial latent infection is established until the next gestation, when the microorganism is reactivated, causing abortion. The precise mechanisms that trigger the awakening of C. abortus are still unknown. Sexual hormones such as estradiol and progesterone have been shown to affect the outcome of infection in other species of the family Chlamydiaceae, while estrogens increase chlamydial infection, progesterone has the opposite effect. To try to establish whether there is a relationship between these events and the latency/ reactivation of C. abortus in the reproductive tract of small ruminants, ovine endometrial (LE) and trophoblastic (AH-1) cells were treated with estradiol or progesterone prior to their infection with C. abortus. The results are compared with those obtained for treatment with penicillin prior to infection, which is a well-established model for studying persistent infection in other chlamydial species. Cells were examined by transmission electron microscopy, and an mRNA expression analysis of 16 genes related to the chlamydial developmental cycle was made.

Results

The changes observed in this study by the action of sex hormones seem to depend on the type of cell where the infection develops. In addition, while the changes are morphologically similar to those induced by treatment with penicillin, the patterns of gene expression are different. Gene expression patterns therefore, seem to depend on the persistence induced models of C. abortus used. Hormone treatments induced aberrant forms in infected endometrial cells but did not affect the chlamydial morphology in trophoblast cells. At the genetic level, hormones did not induce significant changes in the expression of the studied genes.

Conclusions

The results suggest that penicillin induces a state of persistence in in vitro cultured C. abortus with characteristic morphological features and gene transcriptional patterns. However, the influence of hormones on the C. abortus developmental cycle is mediated by changes in the host cell environment. Furthermore, a persistent state in C. abortus cannot be characterised by a single profile of gene expression pattern, but may change depending on the model used to induce persistence.

Docosahexaenoic acid-thyroid hormone combined protocol as a novel approach to metabolic stress disorders: Relation to mitochondrial adaptation via liver PGC-1α and sirtuin1 activation

Docosahexaenoic acid (DHA) and 3,3',5-triiodothyronine (T₃ ) combined protocol affords protection against liver injury via AMPK signaling supporting energy requirements. The aim of this work was to test the hypothesis that a DHA + T₃ accomplish mitochondrial adaptation through downstream upregulation of PPAR-γ coactivator 1α (PGC-1α). Male Sprague-Dawley rats were given daily oral doses of 300 mg DHA/kg or saline (controls) for three consecutive days, followed by 0.05 mg T₃ /kg (or hormone vehicle) ip at the fourth day, or single dose of 0.1 mg T₃ /kg alone. Liver mRNA levels were assayed by qPCR, NAD⁺ /NADH ratios, hepatic proteins, histone 3 acetylation and serum T₃ and β-hydroxybutyrate levels were determined by specific ELISA kits. Combined DHA + T₃ protocol led to increased liver AMPK, PGC-1α, NRF-2, COX-IV, and β-ATP synthase mRNAs, with concomitant higher protein levels of COX-IV and NRF-2, 369% enhancement in the NAD⁺ /NADH ratio, 47% decrease in histone 3 acetylation and 162% increase in serum levels of β-hydroxybutyrate over control values. These changes were reproduced by the higher dose of T₃ without major alterations by DHA or T₃ alone. In conclusion, liver mitochondrial adaptation by DHA + T₃ is associated with PGC-1α upregulation involving enhanced transcription of the coactivator, which may be contributed by PGC-1α deacetylation and phosphorylation by SIRT1 and AMPK activation, respectively. This contention is supported by NRF-2-dependent enhancement in COX-1 and β-ATP synthase induction with higher fatty acid oxidation resulting in a significant ketogenic response, which may represent a suitable strategy for hepatic steatosis with future clinical applications. © 2018 BioFactors, 45(2):271-278, 2019.

Prenatal metformin treatment improves ovarian function in offspring of obese rats

Maternal obesity causes a wide range of impairment in offspring, such as metabolic and reproductive dysfunctions. We previously demonstrated that female offspring of obese rats have increased serum estradiol levels during early postnatal life, probably because of decreased hepatic cytochrome P450 3A2 levels, which could lead to early onset of puberty and polycystic ovary condition in adulthood. Using metformin during pregnancy and nursing to improve the metabolic status of obese mothers could prevent the sequence of events that lead to an increase in postnatal serum estradiol levels in female offspring and, hence, reproductive dysfunction. We found that metformin prevented an increase in serum estradiol levels at postnatal day 14 in female offspring of obese mothers, which was associated with a restoration of hepatic cytochrome P450 3A2 levels to control values. Treatment using metformin could not prevent advanced puberty, but we observed that the number of antral follicles, follicular cysts and multi-oocyte follicles returned to control values in the female offspring of obese mothers treated with metformin. We also observed an increase in the levels of norepinephrine and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol in the ovaries, indicating increased sympathetic activity in female offspring induced by an obesogenic uterine environment. We found that this effect was prevented by metformin administration. From the results of this study, we concluded that metformin administration to obese mothers during pregnancy and nursing partially prevents ovarian dysfunction in female offspring during adulthood.

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.

Increase in endogenous estradiol in the progeny of obese rats is associated with precocious puberty and altered follicular development in adulthood

Maternal obesity during pregnancy has been related with several pathological states in offspring. However, the impact of maternal obesity on reproductive system on the progeny is beginning to be elucidated. In this work, we characterize the effect of maternal obesity on puberty onset and follicular development in adult offspring in rats. We also propose that alterations in ovarian physiology observed in offspring of obese mothers are due to increased levels of estradiol during early development. Offspring of control dams and offspring of dams exposed to a high-fat diet (HF) were studied at postnatal days (PND) 1, 7, 14, 30, 60, and 120. Body weight and onset of puberty were measured. Counting of ovarian follicles was performed at PND 60 and 120. Serum estradiol, estriol, androstenedione, FSH, LH, and insulin levels were measured by ELISA. Hepatic CYP3A2 expression was determined by Western blot. HF rats had a higher weight than controls at all ages and they also had a precocious puberty. Estradiol levels were increased while CYP3A2 expression was reduced from PND 1 until PND 60 in HF rats compared to controls. Estriol was decreased at PND60 in HF rats. Ovaries from HF rats had a decrease in antral follicles at PND60 and PND120 and an increase in follicular cysts at PND60 and PND120. In this work, we demonstrated that maternal obesity in rats alters follicular development and induces follicular cysts generation in the adult offspring. We observed that maternal obesity produces an endocrine disruption through increasing endogenous estradiol in early life. A programmed failure in hepatic metabolism of estradiol is probably the cause of its increase.

Risk factors for candidemia in non-neutropenic critical patients in Colombia

OBJECTIVES

Due to the increase in isolation of Candida spp. in critically ill patients, and the high mortality and economic costs which this infection entails, a study was made of the risk factors associated to candidemia in critically ill patients from 7 intensive care units in Colombia.

MATERIALS AND METHODS

A multicenter matched case-control study was conducted in 7 intensive care units of 3 university hospitals. Data on overall length of hospital stay (including both general wards and the intensive care unit) were recorded.

RESULTS

A total of 243 subjects (81 cases and 162 controls) between January 2008 and December 2012 were included. In order of frequency, C. albicans, C. tropicalis and C. parapsilosis were isolated. The main identified risk factors were: overall length of hospital stay>25 days (OR 5.33, 95% CI 2.6-10.9), use of meropenem (OR 3.75, 95% CI 1.86-7.5), abdominal surgery (OR 2.9, 95% CI 1.39-6.06) and hemodialysis (OR 3.35, 95% CI 1.5-7.7). No differences in mortality between patients with candidemia and controls were found (39.5 vs. 36.5%, respectively, P=.66) were found.

CONCLUSIONS

In Colombia, a long hospital stay, abdominal surgery, the use of meropenem and hemodialysis were identified as risk factors for candidemia.

Intratracheal infection as an efficient route for testing vaccines against Chlamydia abortus in sheep

Pregnant ewes have been widely used to test vaccines against Chlamydia abortus. However, this model entails many disadvantages such as high economic costs and long periods of pregnancy. The murine model is very useful for specific studies but cannot replace the natural host for the later stages of vaccine evaluation. Therefore, a non-pregnant model of the natural host might be useful for a vaccine trial to select the best vaccine candidates prior to use of the pregnant model. With this aim, two routes of infection were assessed in young non-pregnant sheep, namely, intranasal (IN) and intratracheal (IT). In addition, groups of non-vaccinated sheep and sheep immunised with an inactivated vaccine were established to investigate the suitability of the model for testing vaccines. After the experimental infection, isolation of the microorganism in several organs, with pathological and immunohistochemical analyses, antibody production assessment and investigation by PCR of the presence of chlamydia in the vagina or rectum were carried out. Experimental IT inoculation of C. abortus induced pneumonia in sheep during the first few days post-infection, confirming the suitability of the IT route for testing vaccines in the natural host. The course of infection and the resulting pathological signs were less severe in vaccinated sheep compared with non-vaccinated animals, demonstrating the success of vaccination. IN infection did not produce evident lesions or demonstrate the presence of chlamydial antigen in the lungs and cannot be considered an appropriate model for testing vaccines.

Assessment of neurofeedback training by means of motor imagery based-BCI for cognitive rehabilitation

The age-related impairment is an increasing problem due to the aging suffered by the population, especially in developed countries. It is usual to use electroencephalogram (EEG)-based Brain Computer Interface (BCI) systems by means of the signal in order to assist and to improve the quality of life of people with disabilities. However, a parallel research line addresses the problem by the use of BCI systems as a way to train cognitive areas to achieve a deceleration of cognitive impairment or even an improvement. In this regard, a neurofeedback training (NFT) tool using motor imagery-based BCI, was developed. Training consists on imagery motor exercises combined with memory and logical relation tasks. In order to assess the effectiveness of the application 40 subjects, older than 59 years old, took part in this study. Our NFT application was tested by 20 subjects and their scores of a neuropsychological test were compared with the remaining 20 subjects who did not perform the NFT. Results show a significant improvement of three cognitive features after performing the NFT: visual perception, expressive speech, and immediate memory. Therefore, evidences show that the performance of a NFT tool based on motor imagery tasks could be a positive activity for slow down the aging effects.

Effect of inulin, β-Glucan and their mixtures on emulsion stability, color and textural parameters of cooked meat batters

The effects of fat level (20.0, 12.5 and 5.0%), Inulin (gel-IG, and powder-IP) and β-Glucan (βG) on emulsion stability, color, textural characteristics and microstructure of cooked meat batters were investigated. Reducing fat to 5.0% increased cooking loss and decreased emulsion stability, lightness, hardness and fracturability of cooked emulsions. Inulin, βG, and their mixtures were used as fat replacers in low fat formulations. Adding IP provided better emulsion stability compared to IG, which had no significant effect on stability. IP also produced harder (27-34 N) low fat products with a high fracturability (26-29 N). On the contrary, emulsions containing IG resulted in creamy and softer characteristics. The results were supported by light micrographs, which indicated that appropriate addition of IG and βG mixtures (3%-IG & 0.3%-βG, 6%-IG & 0.6%-βG) could compensate for some of the changes brought about by fat reduction, and maintained several of the textural characteristics of the product as well as reducing cook loss.