Modulation of Postnatal Neurogenesis by Perinatal Asphyxia: Effect of D1 and D2 Dopamine Receptor Agonists

Perinatal asphyxia (PA) is associated to delayed cell death, affecting neurocircuitries of basal ganglia and hippocampus, and long-term neuropsychiatric disabilities. Several compensatory mechanisms have been suggested to take place, including cell proliferation and neurogenesis. There is evidence that PA can increase postnatal neurogenesis in hippocampus and subventricular zone (SVZ), modulated by dopamine, by still unclear mechanisms. We have studied here the effect of selective dopamine receptor agonists on cell death, cell proliferation and neurogenesis in organotypic cultures from control and asphyxia-exposed rats. Hippocampus and SVZ sampled at 1-3 postnatal days were cultured for 20-21 days. At day in vitro (DIV) 19, cultures were treated either with SKF38393 (10 and 100 µM, a D₁ agonist), quinpirole (10 µM, a D₂ agonist) or sulpiride (10 μM, a D₂ antagonist) + quinpirole (10 μM) and BrdU (10 μM, a mitosis marker) for 24 h. At DIV 20-21, cultures were processed for immunocytochemistry for microtubule-associated protein-2 (MAP-2, a neuronal marker), and BrdU, evaluated by confocal microscopy. Some cultures were analysed for cell viability at DIV 20-21 (LIVE/DEAD kit). PA increased cell death, cell proliferation and neurogenesis in hippocampus and SVZ cultures. The increase in cell death, but not in cell proliferation, was inhibited by both SKF38393 and quinpirole treatment. Neurogenesis was increased by quinpirole, but only in hippocampus, in cultures from both asphyxia-exposed and control-animals, effect that was antagonised by sulpiride, leading to the conclusion that dopamine modulates neurogenesis in hippocampus, mainly via D₂ receptors.

Mutagenicity and cytotoxicity of fruits and vegetables evaluated by the Ames test and 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay / Mutagenicidad y citotoxicidad de frutas y vegetales evaluadas por el test de Ames y el ensayo del bromuro de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolio (MTT)

The mutagenic and cytotoxic activity of the aqueous (H2O) and ethanolic (EtOH) extracts of fruits and vegetables were studied by the Ames test and the MTT assay. A significant mutagenic activity was found for three H2O extracts of broccoli ( Brassica oleracea), carrot ( Dacus carota) and licorice ( Glycyrrhiza glabra) and for one EtOH extract of kiwi ( Ananas sativus ) of the nine species analyzed. The frameshift tester strain TA98 was reverted by broccoli (2.4, 4.8 and 9.6 mg/mL; p < 0.01) and carrot (9.6 mg/mL; p < 0.001) aqueous extracts and by kiwi (9.6 mg/mL; p < 0.0001) EtOH extract, whereas strain TA100 was only sensitive to the mutagens of licorice H,O extract, within the nine fruits and vegetables tested. The mutagenic response of the extracts was not altered by the presence of S9 mix. Cytotoxicity was only found for three of the nine species tested. Percentage cytotoxic ac tivities at 4.8 mg/mL in pineapple ( Actinidin diasinensis) and garlic ( Allium sativum) H,O extracts were 77 and 91 %, respectively. Licorice EtOH extract was the only one that showed a cytotoxic activity at all of the concentrations used. The percentage of cytotoxic activity of licorice extract was 63% at 0.24 mg/mL and increased with increasing concentration of licorice up to 4.8 mg/mL. Thus, licorice (EtOH) extract was the most cytotoxic of the species tested.

Protective Effect of a Lactobacillus salivarius Strain of Human Origin

The protective effect of a Lactobacillus salivariusstrain from human faeces (HA8) was evaluated against the cytotoxicity of N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR), N-nitrosodibutylamine (NDBA) and N-nitrosopiperidine (NPIP) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. L. salivariusHA8 strain showed a moderate protective effect against NPYR and weak against NDBA and NPIP. No protective effect against cytotoxicity of NDMA was observed at the bacterial population used. To test the effect of L. salivariusHA8 on cytokine production (interleukin-1 ± (IL-1 ±), interleukin-8 (IL-8) and tumour necrosis factor alpha (TNF-≥)), the human macrophage cell line (THP-1) was cultured in the presence and absence of lipopolysaccharide (LPS). L. salivariusHA8 induced IL-1 ±, IL-8 and TNF-≥ releases when cells were stimulating with and without LPS.

Impact of Dietary Lipids on Colonic Function and Microbiota: An Experimental Approach Involving Orlistat-Induced Fat Malabsorption in Human Volunteers

OBJECTIVES:

High-fat diets alter gut microbiota and barrier function, inducing metabolic endotoxemia and low-grade inflammation. Whether these effects are due to the high dietary lipid content or to the concomitant decrease of carbohydrate intake is unclear. The aim of this study was to determine whether higher amounts of dietary fat reaching the colon (through orlistat administration) affect the colonic ecosystem in healthy volunteers and the effect of the prebiotic oligofructose (OF) in this model.

METHODS:

Forty-one healthy young subjects were distributed among four groups: Control (C), Prebiotic (P), Orlistat (O), and Orlistat/Prebiotic (OP). They consumed a fat-standardized diet (60 g/day) during Week-1 (baseline) and after 1 week of washout, Week-3. During Week-3, they also received their respective treatment (Orlistat: 2 × 120 mg/day, OF: 16 g/day, and maltodextrin as placebo). A 72-h stool collection was carried out at the end of Week-1 (T0) and Week-3 (T1). Fecal fat, calprotectin, and short-chain fatty acids (SCFAs) as well as the antioxidant activity of fecal waters (ferric-reducing antioxidant power), fecal microbiota composition (by deep sequencing), and gut permeability (Sucralose/Lactulose/Mannitol test) were determined at these times.

RESULTS:

Fecal fat excretion was higher in the O (P=0.0050) and OP (P=0.0069) groups. This event was accompanied, in the O group, by an increased calprotectin content (P=0.047) and a decreased fecal antioxidant activity (P=0.047). However, these alterations did not alter gut barrier function and the changes observed in the composition of the fecal microbiota only affected bacterial populations with low relative abundance (<0.01%); in consequences, fecal SCFA remained mainly unchanged. Part of the colonic alterations induced by orlistat were prevented by OF administration.

CONCLUSIONS:

In the context of an equilibrated diet, the acute exposition of the colonic ecosystem to high amounts of dietary lipids is associated with an incremented excretion of fecal calprotectin and pro-oxidant activity of the colonic content, in the absence of significant changes in the microbiota.

Fibronectin stimulates human sperm capacitation through the cyclic AMP/protein kinase A pathway

STUDY QUESTION

Does fibronectin (Fn) stimulate the sperm capacitation process in humans?

SUMMARY ANSWER

Fibronectin stimulates human sperm capacitation.

WHAT IS KNOWN ALREADY

Capacitation is a process that occurs in the oviduct. It has been suggested that some molecules present in the oviductal fluid and cells as well as proteins present in the cumulus oophorus could be involved in the modulation of sperm function and their acquisition of fertilizing capacity. Fibronectin is a glycoprotein that is present in the fluid and the oviduct epithelium, and its receptor (alpha 5 beta 1 integrin) is present in human sperm. When alpha 5 beta 1 (α5β1) integrin binds to fibronectin, intracellular signals similar to the process of sperm capacitation are activated.

STUDY DESIGN, SIZE, DURATION

Human sperm were selected via a percoll gradient and were then incubated in non-capacitated medium (NCM) or reconstituted capacitated medium (RCM), in the presence or absence of fibronectin for different time periods. A total of 39 donors were used during the study, which lasted 3 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Freshly ejaculated sperm from healthy volunteers were obtained by masturbation. All semen samples were normal according to the World Health Organization parameters. Six approaches were used to determine the effects of fibronectin on sperm capacitation: chlortetracycline (CTC) assay, heterologous co-culture of human sperm with bovine oviductal epithelial cells (BOEC), measurement of cyclic (c) AMP levels, activity of protein kinase A (PKA), phosphorylation of proteins in tyrosine (Tyr) residues, and induction of acrosome reaction with progesterone.

MAIN RESULTS AND THE ROLE OF CHANCE

When sperm were incubated in RCM in the presence of Fn, we observed differences with respect to sperm incubated in RCM without Fn (control): (i) a 10% increase in the percentage of sperm with the B pattern (capacitated sperm) of CTC fluorescence from the beginning of capacitation (P < 0.001); (ii) an effect on both the concentration of cAMP (P < 0.05) and PKA activity (P < 0.05) during early capacitation; (iii) an increase in the degree of phosphorylation of proteins on tyrosine residues after 60 min of capacitation (P < 0.01); (iv) an increase in the percentage of acrosome-reacted sperm in response to progesterone (P < 0.05); and (v) a decrease in the percentage of sperm attached to BOEC (P < 0.05). Moreover, we noted that the effect of Fn was specific and mediated by alpha 5 beta 1 integrin (P < 0.001). Fn by itself had no effect on sperm capacitation.

LIMITATIONS, REASONS FOR CAUTION

This study was carried out with sperm from young adult men. Men with abnormal semen samples were excluded. The results cannot be directly extrapolated to other mammalian species.

WIDER IMPLICATIONS OF THE FINDINGS

Currently, male subfertility has become a huge public health problem, which makes it imperative to develop new treatments. This is a novel discovery that extends our current knowledge concerning normal and pathological sperm physiology as well as events that regulate the process of fertilization.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by grants from FONDECYT (1130341, E.S.D. and 1120056, P.M.) and FONCYT (PIP 2011-0496, S.P.-M). The authors have no conflicts of interest.

Novel fiber-rich lentil flours as snack-type functional foods: an extrusion cooking effect on bioactive compounds

The effect of extrusion processing on inositol phosphates.

Manufactured silver nanoparticles of different sizes induced DNA strand breaks and oxidative DNA damage in hepatoma and leukaemia cells and in dermal and pulmonary fibroblasts

Many classes of silver nanoparticles (AgNPs) have been synthesized and widely applied, but no conclusive information on their potential cytotoxicity and genotoxicity mechanisms is available. Therefore, the purpose of this study was to compare the potential genotoxic effects (DNA strand breaks and oxidative DNA damage) of 4.7 nm coated and 42 nm uncoated AgNPs, using the comet assay, in four relevant human cell lines (hepatoma, leukaemia, and dermal and pulmonary fibroblasts) in order to understand the impact of such nanomaterials on cellular DNA. The results indicated that in all cell lines tested, 4.7 nm coated (0.1-1.6 μg ml⁻¹) and 42 nm uncoated (0.1-6.7 μg ml⁻¹) AgNPs increased DNA strand breaks in a dose- and size-dependent manner following 24 h treatment, the smaller AgNPs being more genotoxic. Human pulmonary fibroblasts showed the highest sensitivity to the AgNPs. A modified comet assay using endonuclease III and formamidopyrimidine- DNA glycosylase restriction enzymes showed that in tumoral and normal human dermal fibroblasts, pyrimidines and purines were oxidatively damaged by both AgNPs, but the damage was not size-dependent. However, in human pulmonary fibroblasts, no oxidative damage was observed after treatment with 42 nm AgNPs. In conclusion, both AgNP sizes induced DNA damage in human cells, and this damage could be related to oxidative stress.

Probiotic screening and safety evaluation of Lactobacillus strains from plants, artisanal goat cheese, human stools, and breast milk

The aim of this study was to select autochthonous strains of Lactobacillus from stools of healthy infants and adults, human milk, artisanal goat cheese, and fruits and vegetables according to their probiotic properties and safety. From 421 strains of Lactobacillus isolated, 102 (24.2%) were shown to be tolerant to gastric pH and bile salts; they were used to determine their anti-Helicobacter pylori (agar diffusion assay), antioxidant (oxygen radical absorption capacity), and anti-inflammatory (inhibition of interleukin-8 release by tumor necrosis factor-α-stimulated HT-29 cells) activities as well as their ability to adhere to intestinal (Caco-2) and gastric (AGS) epithelial cells. Results obtained were compared with three commercial probiotic Lactobacillus rhamnosus GG, L. plantarum 299v, and L. johnsonii NCC533. The five strains most efficient according to these activities were subsequently identified by sequencing their 16S rRNA gene, their susceptibility to antibiotics was determined, and their safety evaluated in mice. One strain of L. plantarum was discarded due to the higher prevalence of liver bacterial translocation observed in the animals fed this strain. In conclusion, four autochthonous strains of L. rhamnosus were finally selected with probiotic properties and safety allowing their eventual use in human studies. These results contribute to increase the diversity of probiotic strains available for the development of nutraceuticals and functional foods.

Virus and Antibody Diagnostics for Swine Samples of the Dominican Republic Collected in Regions Near the Border to Haiti

The Dominican Republic (DR) and Haiti share the island of Hispaniola, and reportable transboundary animal diseases have been introduced between the two countries historically. Outbreaks of severe teschovirus encephalomyelitis in pigs began occurring in Haiti in February 2009, and a field and laboratort study in April 2010 indicated that the teschovirus disease is prevalent in many regions in Haiti including areas near the border with DR and that other viral disease agents, including CSF virus (CSFV), porcine circovirus type 2 (PCV-2), porcine reproductive and respiratory syndrome virus (PRRSV), and swine influenza virus (SIV), are present in the swine population in these regions. The purpose of this study was to evaluate the introduction of teschovirus encephalomyelitis from Haiti to DR and to identify the other viral disease agents present in the swine population in regions of DR near the border with Haiti. Six of 7 brains and 6 of 7 spinal cords collected from pigs with central nervous system (CNS) signs were positive in reverse transcription-polymerase chain reaction for PTV. Genome sequencing on the Dominican PTV and phylogenetic analysis on the polyprotein of PTV strains indicate that the sequence of the Dominican PTV is 99.1% identical to the Haitian isolate and closely related to other PTV-1 strains in the world. Among 109 serum samples tested, 65 (59.6%) were positive for antibodies to PCV-2, and 51 (46.8%) were positive for antibodies to CSFV. Fifty-four of the 109 serum samples were tested for antibodies to other agents. Among the 54 samples, 20 (37.0%) were seropositive to PTV-1, 17 (31.5%) tested seropositive to SIV H3N2, 12 (22.2%) were seropositive to SIV H1N1, and 1 (1.9%) was seropositive to PRRSV.

Polyphenols protect the epithelial barrier function of Caco-2 cells exposed to indomethacin through the modulation of occludin and zonula occludens-1 expression

The aim of this study was to determine the protective effect of quercetin, epigallocatechingallate, resveratrol, and rutin against the disruption of epithelial integrity induced by indomethacin in Caco-2 cell monolayers. Indomethacin decreased the transepithelial electrical resistance and increased the permeability of the monolayers to fluorescein-dextran. These alterations were abolished by all the tested polyphenols but rutin, with quercetin being the most efficient. The protective effect of quercetin was associated with its capacity to inhibit the redistribution of ZO-1 protein induced in the tight junction by indomethacin or rotenone, a mitochondrial complex-I inhibitor, and to prevent the decrease of ZO-1 and occludin expression induced by indomethacin. The fact that the antioxidant polyphenols assayed in this study differ in their protective capacity against the epithelial damage induced by indomethacin suggests that this damage is due to the ability of this agent to induce not only oxidative stress but also mitochondrial dysfunction.

Phylogenetic and phylogeographic analysis of the genus Orestias (Teleostei: Cyprinodontidae) in the southern Chilean Altiplano: the relevance of ancient and recent divergence processes in speciation

This study presents phylogenetic molecular data of the Chilean species of Orestias to propose an allopatric divergence hypothesis and phylogeographic evidence that suggests the relevance of abiotic factors in promoting population divergence in this complex. The results reveal that diversification is still ongoing, e.g. in the Ascotán salt pan, where populations of Orestias ascotanensis restricted to individual freshwater springs exhibit strong genetic differentiation, reflecting putative independent evolutionary units. Diversification of Orestias in the southern Altiplano may be linked to historical vicariant events and contemporary variation in water level; these processes may have affected the populations from the Plio-Pleistocene until the present.

Preclinical report on allogeneic uterus transplantation in non-human primates

STUDY QUESTION

Is it possible to perform allogeneic uterus transplantation (UTx) with a donation from a live donor in a non-human primate species and what immunosuppression is needed to prevent rejection?

SUMMARY ANSWER

Allogeneic UTx in the baboon is a donor- and recipient-safe surgical procedure; immunosuppression with induction therapy and a triple protocol should be used.

WHAT IS KNOWN ALREADY

UTx may become a treatment for absolute uterine factor infertility. Autologous UTx models have been developed in non-human primates with reports on long-term survival of the uterine grafts. STUDY DESIGN, SIZEAND DURATION: This experimental study included 18 female baboons as uterus donors and 18 female baboons as uterus recipients. The follow-up time was 5-8 weeks.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

Uterus retrieval was performed with extended hysterectomy including bilateral uterine and internal iliac arteries and ovarian veins. After UTx, with vascular anastomoses unilateral to the internal iliac artery and the external iliac vein, the uterus recipients received one of the following: no immunosuppression (n = 4); monotherapy (oral slow release tacrolimus) (n = 4) or induction therapy (antithymocyte globulin) followed by triple therapy (tacrolimus, mycophenolate, corticosteroids; n = 10). Surgical parameters, survival, immunosuppression and rejection patterns were evaluated.

MAIN RESULTS AND THE ROLE OF CHANCE

The durations of uterus retrieval and recipient surgery were around 3 and 3.5 h, respectively. The total ischemic time was around 3 h. All the recipients and the donors survived the surgery. All the recipients presented rejection to some extent within the first weeks following UTx. In one recipient, the uterus was of normal appearance at the end of the study period. In spite of occasional high (>60 ng/ml) blood levels of tacrolimus, there was no evidence of nephrotoxicity.

LIMITATIONS AND REASONS FOR CAUTION

This initial non-human primate allogeneic UTx study indicates that further research is needed to optimize immunosuppression protocols in order to avoid uterine rejection.

WIDER IMPLICATIONS OF THE FINDINGS

The findings suggest that allogeneic UTx in primate species is feasible but continued work on this issue is needed.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the Swedish Research Council, ALF University of Gothenburg, Hjalmar Svensson Foundation and by Jane and Dan Olsson Research Foundation. The authors do not have any competing interest.

Fatty acids profiles of some Spanish wild vegetables

Polyunsaturated fatty acids play an important role in human nutrition, being associated with several health benefits. The analyzed vegetables, in spite of its low fat content, lower than 2%, present a high proportion of polyunsaturated fatty acids of n-3, n-6 and n-9 series, such as α-linolenic, linoleic and oleic acids, respectively. Wild edible plants contain in general a good balance of n-6 and n-3 fatty acids. The present study tries to contribute to the preservation and valorization of traditional food resources, studying the fatty acids profile of 20 wild vegetables by gas-liquid chromatography with flame ionization detection. Results show that species in which leaves are predominant in their edible parts have in general the highest polyunsaturated fatty acid/saturated fatty acid ratios: Rumex pulcher (5.44), Cichorium intybus (5.14) and Papaver rhoeas (5.00). Due to the low n-6/n-3 ratios of the majority of the samples, they can be considered interesting sources of n-3 fatty acids, especially those with higher total fat amount, such as Bryonia dioica, Chondrilla juncea or Montia fontana, with the highest contents of α-linolenic acid (67.78, 56.27 and 47.65%, respectively). The wild asparaguses of Asparagus acutifolius and Tamus communis stand out for their linoleic acid content (42.29 and 42.45%, respectively). All these features reinforce the interest of including wild plants in diet, as an alternative to the variety of vegetables normally used.

Complement C3 Genotyping of Slow and Fast Variants by Real Time PCR-High Resolution Melting

“Slow” and “Fast” C3 complement variants (C3S and C3F) result from a g.304C>G polymorphism that changes arginine to glycine at position 102. C3 variants are associated with complement-mediated diseases and outcome in transplantation. In this work C3 genotyping is achieved by a Real Time PCR - High Resolution Melting (RT-PCR-HRM) optimized method. In an analysis of 49 subjects, 10.2% were C3FF, 36.7% were C3SF and 53.1% were C3SS. Allelic frequencies (70% for C3S and 30% for C3F) were in Hardy-Weinberg equilibrium and similar to those published previously. When comparing RT-PCR-HRM with the currently used Tetraprimer-Amplification Refractory Mutation System PCR (T-ARMS-PCR), coincidence was 93.8%. The procedure shown here includes a single primer pair and low DNA amount per reaction. Detection of C3 variants by RT-PCR-HRM is accurate, easy, fast and low cost, and it may be the method of choice for C3 genotyping.

Biofiltration of hydrogen sulfide by Sulfolobus metallicus at high temperatures

Biofiltration of reduced sulfur compounds such as hydrogen sulfide has been mainly applied to emissions at mild temperatures (25 to 35 °C). However, an important number of industrial gaseous emission containing sulfur compounds, from diverse industrial sectors (petroleum refinery, cellulose production, smelting, rendering plants and food industries) are emitted at temperatures over 50 °C. Most of the studies on thermophilic systems report that a higher elimination capacity can be obtained at elevated temperature, allowing the design of smaller equipment for the same loading rate than that required for removing the same load under mesophilic conditions. A biotrickling filter inoculated with Sulfolobus metallicus, which operates at three different residence times, 60, 80 and 120 s, and two different temperatures (45 and 55 °C) for treating H(2)S is reported. The input loads of H(2)S were progressively increased from 0 to 100 gS/m(3). The aim of this study was to determine the capacity and ability of S. metallicus to oxidize H(2)S at high temperatures. The better removal capacity of H(2)S obtained was 37.1 ± 1.7 gS/m(3) h at 55 °C for a residence time of 120 s. The difference of the removal capacity of H(2)S between the two temperatures was 4 g/m(3) h on average of sulfur removal for the different residence times.