Diversity of probiotic adhesion genes in the gastrointestinal tract of goats

Gastrointestinal (GI) microflora is an important system in the host, as it has both pathogenic and probiotic bacteria. Most of the studies were focused on the human gut microflora and the available information on the intestinal microflora of goats was limited. This urged the need to inspect the impacts of the goat's gut microflora. Metagenomic investigation of probiotic bacteria in the GI tract of goat is one of the challenging streams because of the less available data of the uncultivable bacteria. In our report, comparative analysis of metagenomic and enrichment samples of goat intestinal content was done and this approach will be helpful in analyzing the identification of uncultivable and cultivable probiotic bacteria. This study mainly focused on three key probiotic adhesion genes, such as EF-Tu, mapA, and mub. The GI of four different goats were investigated for these genes. The data from this study showed that there is a wide diversity of these genes among goat intestinal samples.     

Interaction of diesel exhaust particles with human, rat and mouse erythrocytes in vitro

Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 μg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 μg/ml) and TAS (at 100 μg/ml) activities. In conclusion, DEP caused species-dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.     

Effects of Side Chains on Thiazolothiazole‐Based Copolymer Semiconductors for High Performance Solar Cells

New thiazolothiazole‐dithienosilole copolymer semiconductors bearing side chains of different type, size, and topology were synthesized and used to demonstrate the influence of side chains on morphology, charge transport and photovoltaic properties. The field effect mobility of holes varied from 0.01‐0.03 cm²V^?1s^?1 in PSOTT and PSEHTT to 0.12 cm²V^?1s^?1 in PSOxTT. The average power conversion efficiency of solar cells under 1.0 sun illumination could be varied from 2.1% in PSOxTT and 4.1% in PSOTT to 5.0% in PSEHTT. The highest photovoltaic efficiency achieved in PSEHTT, that has all‐branched alkyl side chains and face‐on π‐stacking orientation, was corroborated by its enhanced charge photogeneration observed by transient absorption spectroscopy.     

Bioelectricity production from acidic food waste leachate using microbial fuel cells: Effect of microbial inocula

The effects of three different inocula (domestic wastewater, activated sludge, and anaerobic sludge) on the treatment of acidic food waste leachate in microbial fuel cells (MFCs) were evaluated. A food waste leachate (pH 4.76; 1000 mg chemical oxygen demand (COD)/L) was used as the substrate. The results indicate that the leachate itself can enable electricity production in an MFC, but the co-addition of different inocula significantly reduces the start-up time (approximately 7 days). High COD and volatile fatty acids removal (>87%) were obtained in all MFCs but with only low coulombic efficiencies (CEs) (14–20%). The highest power (432 mW/m³) and CE (20%) were obtained with anaerobic sludge as the co-inoculum. Microbial community analysis (PCR-DGGE) of the established biofilms suggested that the superior performance of the anaerobic sludge-MFC was associated with the enrichment of both fermentative (Clostridium sp. and Bacteroides sp.) and electrogenic bacteria (Magnetospirillum sp. and Geobacter sp.) at the anode.     

Carvacrol modulates instability of xenobiotic metabolizing enzymes and downregulates the expressions of PCNA,MMP-2, and MMP-9 during diethylnitrosamine-induced hepatocarcinogenesis in rats

Vascular calcification (VC) is highly associated with increased morbidity and mortality in patients with advanced chronic kidney disease. Paracrine/autocrine factors such as vasoactive peptides are involved in VC development. Here, we investigated the expression of the novel peptide C-type natriuretic peptide (CNP) in the vasculature, tested its ability to prevent VC in vivo and in vitro, and examined the mechanism involved. Rat aortic VC was induced by vitamin D3 plus nicotine (VDN). CNP (500 ng/kg/h) was administered by mini-osmotic pump. Calcification was examined by von Kossa staining; CNP and cyclic guanosine monophosphate (cGMP) contents were detected by radioimmunoassay, and mRNA and protein levels were examined by real-time PCR and Western blot analysis in aortas and calcified vascular smooth muscle cells (VSMCs). VDN-treated rat aortas showed higher CNP content and decreased expression of its receptor natriuretic peptide receptor B, along with increased vascular calcium deposition and alkaline phosphatase (ALP) activity. Low CNP levels were accompanied by increased vascular calcium deposition and ALP activity in VDN-treated rats when compared to vehicle treatment, which was further confirmed in cultured VSMCs. Administration of CNP greatly reduced VC in VDN-treated aortas compared with controls, which was confirmed in calcified VSMCs. The decrease in alpha-actin expression was ameliorated by CNP in vitro. Moreover, protein expression levels of osteopontin (OPN) were significantly up-regulated in calcified aortas, and CNP increased OPN expression in calcified aortas. Furthermore, CNP downregulated OPN and bone morphogenic protein 2 (BMP-2) expression in calcified aortas and VSMCs. Modulation of OPN and BMP-2 expression by CNP and the beneficial effects of CNP on calcified VSMCs were blocked significantly by protein kinase G inhibitor H7. Impaired local endogenous CNP and its receptor system may be associated with increased mineralization in vivo in rat aortas with VC, and administration of CNP inhibits VC development in vivo and in vitro, at least in part, via a cGMP/PKG pathway.     

Transcriptional expression changes of glucose metabolism genes after exercise in thoroughbred horses

Physical exercise induces gene expression changes that trigger glucose metabolism pathways in organisms. In the present study, we monitored the expression levels of LDHA (lactate dehydrogenase) and GYS1 (glycogen synthase 1) in the blood, to confirm the roles of these genes in exercise physiology. LDHA and GYS1 are related to glucose metabolism and fatigue recovery, and these processes could elicit economically important traits in racehorses. We collected blood samples from three retired thoroughbred racehorses, pre-exercise and immediately after 30 min of exercise. We extracted total RNA and small RNA (≤ 200 nucleotide-long) from the blood, and assessed the expression levels of LDHA, GYS1, and microRNAs (miRNAs), by using qRT-PCR. We showed that LDHA and GYS1 were down-regulated, whereas eca-miR-33a and miR-17 were up-regulated, after exercise. We used sequences from the 3′ UTR of LDHA and GYS1, containing eca-miR-33a and miR-17 binding sites, to observe the down-regulation activity of each gene expression. We observed that the two miRNAs, namely, eca-miR-33a and miR-17, inhibited LDHA and GYS1 expression via binding to the 3′ UTR sequences of each gene. Our results indicate that eca-miR-33a and miR-17 play important roles in the glucose metabolism pathway. In addition, our findings provide a basis for further investigation of the exercise metabolism of racehorses.     

Overexpression of SaRBP1 enhances tolerance of Arabidopsis to salt stress

Abiotic stresses are the major concern in recent years as their effect on world food production is constantly increasing. We have obtained salt tolerant Arabidopsis lines overexpressing SaRBP1 (Suaeda asparagoides RNA binding protein 1) of a Korean halophyte, S. asparagoides. Homozygous T3 Arabidopsis transgenic lines were developed and used for salt stress tolerance studies. The transgenic seedlings displayed tolerance to salt and mannitol compared to the wild type (WT) seedlings. Transgenic lines produced longer primary roots, more fresh weight, and higher number of lateral roots than WT. In planta stress tolerance assay results showed that the survival rates of transgenic plants were significantly higher than WT plants. Transgenic lines showed delayed germination under 200 mM NaCl stress. In addition, the transgenics showed higher water retention ability than WT. Subcellular localization results revealed that SaRBP1 was targeted to the cytoplasm. Northwestern blot analysis results confirmed the RNA binding property of SaRBP1. Quantitative Real-Time Polymerase Chain Reaction results revealed that many stress marker genes were upregulated by SaRBP1 overexpression. Thus, our data demonstrate that SaRBP1 overexpression lines are tolerant to salt stress. Hence, this is the first report for the functional characterization of SaRBP1, a novel RBP gene isolated from S. asparagoides cDNA library.     

Recombinant Lactobacillus plantarum expressing and secreting heterologous oxalate decarboxylase prevents renal calcium oxalate stone deposition in experimental rats

Background

Calcium oxalate (CaOx) is the major constituent of about 75% of all urinary stone and the secondary hyperoxaluria is a primary risk factor. Current treatment options for the patients with hyperoxaluria and CaOx stone diseases are limited. Oxalate degrading bacteria might have beneficial effects on urinary oxalate excretion resulting from decreased intestinal oxalate concentration and absorption. Thus, the aim of the present study is to examine the in vivo oxalate degrading ability of genetically engineered Lactobacillus plantarum (L. plantarum) that constitutively expressing and secreting heterologous oxalate decarboxylase (OxdC) for prevention of CaOx stone formation in rats. The recombinants strain of L. plantarum that constitutively secreting (WCFS1OxdC) and non-secreting (NC8OxdC) OxdC has been developed by using expression vector pSIP401. The in vivo oxalate degradation ability for this recombinants strain was carried out in a male wistar albino rats. The group I control; groups II, III, IV and V rats were fed with 5% potassium oxalate diet and 14^th day onwards group II, III, IV and V were received esophageal gavage of L. plantarum WCFS1, WCFS1OxdC and NC8OxdC respectively for 2-week period. The urinary and serum biochemistry and histopathology of the kidney were carried out. The experimental data were analyzed using one-way ANOVA followed by Duncan’s multiple-range test.

Results

Recombinants L. plantarum constitutively express and secretes the functional OxdC and could degrade the oxalate up to 70–77% under in vitro. The recombinant bacterial treated rats in groups IV and V showed significant reduction of urinary oxalate, calcium, uric acid, creatinine and serum uric acid, BUN/creatinine ratio compared to group II and III rats (P < 0.05). Oxalate levels in kidney homogenate of groups IV and V were showed significant reduction than group II and III rats (P < 0.05). Microscopic observations revealed a high score (4+) of CaOx crystal in kidneys of groups II and III, whereas no crystal in group IV and a lower score (1+) in group V.

Conclusion

The present results indicate that artificial colonization of recombinant strain, WCFS1OxdC and NC8OxdC, capable of reduce urinary oxalate excretion and CaOx crystal deposition by increased intestinal oxalate degradation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-014-0086-y) contains supplementary material, which is available to authorized users.