Chicken Liver Tissue Research Articles

Study of mitochondrial swelling, membrane fluidity and ROS production induced by nano-TiO2 and prevented by Fe incorporation.

The potential impact of TiO2 and Fe incorporated TiO2 nanoparticles at the organelle level has been reported. The toxicity of the samples on mitochondria isolated from chicken liver tissue has been examined through mitochondrial swelling, membrane fluidity, ROS generation capacity, and activity of complex II. The toxic effect of TiO2 was prevented by incorporating Fe into the TiO2 matrix at different concentrations. The activity of the succinate dehydrogenase enzyme complex was affected and permeabilization of the mitochondrial inner membrane to H+ and K+ and its alteration in membrane fluidity at 100 μg mL-1 of nano-TiO2 dosage were investigated, which showed significant changes in the anisotropy of DPH-labeled mitochondria. Fe incorporation into the TiO2 matrix makes it more biocompatible by changing its structure and morphology.

Inhibition of Lipopolysaccharide-Induced Inflammation of Chicken Liver Tissue by Selenomethionine via TLR4-NF-κB-NLRP3 Signaling Pathway.

Selenium (Se) is important in many physiological processes, such as antioxidant processes and inflammation. The aim of our experiments was to investigate the molecular mechanism that selenomethionine could reduce the lipopolysaccharide (LPS)-induced inflammation by inhibiting the TLR4-NF-κB-NLRP3 signaling pathway. Eighty broilers were randomly and evenly divided into two groups, giving normal Se content diets (Con group, 0.2 mg Se/kg diet) and Se-rich basal diets (Se group, 0.5 mg selenomethionine/kg diet) for 90 days. Se-rich basal diets were based on 0.2 mg/kg sodium selenite contained. Five hours before euthanized, 20 broilers were randomly selected from each group and given lipopolysaccharide (200 μg/kg BW) by intraperitoneal injection, Con+LPS group and Se+LPS group, respectively. The Con group and Se group were given equal saline by intraperitoneal injection. We observed the microscopic pathological changes of liver tissue detected oxidative stress by kit and detected the expression of inflammatory factors, heat shock protein (HSP), and nod-like receptor protein 3 (NLRP3)-related genes by qRT-PCR and Western blot. With the microscope, we found the Con+LPS group had obvious inflammatory lesions such as sinusoidal congestion, but the damage was significantly alleviated in the Se+LPS group. In the Con+LPS group, the activity of GSH-Px and the content of GSH were significantly decreased compared with those in the Con group; however, they are increased in the Se group and in the Se + LPS group. Inflammatory factors (MyD88, NF-κB, TNF-α, IL-1β, IL-6, IL-12, IL-18, iNOS, and COX-2), heat shock proteins (HSP27, HSP60, HSP70, and HSP90), and the expression of NLRP3 and caspase-1 increased in the Con+LPS group compared with those in the Con group, while they were lower in the Se+LPS group than in the Con+LPS group. We concluded that selenomethionine inhibits the LPS-induced inflammation of liver tissue via suppressing the TLR4-NF-κB-NLRP3 signaling pathway.

Assessment of histopathological effect of factory effluents on the liver and kidney tissues of chickens (Gallus gallus domestica) reared around factory sites in Nnewi Metropolis, Anambra State, Nigeria

Exposure to factory effluents comes with deleterious consequences. The purpose of this study was to assess the histopathological effect of factory effluents on the liver and kidney tissues of chickens (Gallus gallus domestica) reared around factory sites in Nnewi Metropolis, Anambra State, Nigeria. A total of twenty-nine chicks comprising of sixteen chicks exposed to factory sites and thirteen non-exposed chicks were grown to adult birds (chickens) for the study and were allowed to feed from the surrounding homeland of the factories including lead acid battery manufacturing factory (A), metal fabricating factory (B) and metal forging factory (C) respectively until they were aged between four and five months as adult birds (chickens) for the study. The chickens were sacrificed to obtain the liver and kidney tissues for histological analyses. The histopathological evaluation of the effect of the factory effluents on the liver and kidney tissues of birds reared around the four factories (A-D) and control were done by microscopic examination of haematoxylin and eosin (H&E) stained sections. The results obtained in factory A, B and C showed widening of the liver central vein and thickening of the vessels with invasion of the surrounding areas by chronic inflammatory cells as against the controls which showed fairly normal liver tissues with normal liver parenchyma cells with a central vein containing blood cells. Also, the photomicrographs of the kidney tissues of birds reared around factory A, B and C showed evidence of marked glomerulo-nephritis and hypercellularity with evidence of glomerulosclerosis and hyalinization of the glomeruli as against the normal glomeruli and tubules found in the control birds. These results indicate that the environment where these birds are reared is a potential threat to the lives of the birds reared around these factories. Keywords: Factory site, Factory effluents, Liver, Kidney, Chicken (Gallus gallus domestica), Nnewi metropolis.

Effects of copper nanoparticles on the morphological and physiological changes in chicken

Copper nanoparticles (nCu) have a wide range of applications in many different fields of life. In poultry farming, nCu is well-known as a feed additive to stimulate the development, a good antimicrobial agent and a suppressor of diarrhea. The aim of this study is to perform the analysis of biosafety of nCu. In this study, chickens were treated with drinking water containing 2 mg/L or 1000 mg/L nCu. After 5 weeks of treatment, the survival rate, dry body weight, Cu content in serum and liver tissues of chickens were examined. Liver and kidney functions were also determined by measuring serum levels of ALT, AST, and creatinine. As a result, chickens treated with drinking containing 2 mg/L nCu had no changes in liver and kidney functions as well as their body weights. However, treatment of chickens with 1000 mg/L nCu caused accumulationof Cu in the serum and liver and increase of the serum levels of ALT and AST compared with control group. Apparently they sick and did not develop properly. In conclusion, nCu concentration at 2 mg/L may be recommended for the agricultural, feed and medicine formulations to meet biological safety.ALT, AST, creatinine, nCu, chicken.

Identification of key genes and molecular mechanisms associated with low egg production of broiler breeder hens in ad libitum

BackgroundOverfeeding reduces laying performance in broiler breeder hens, which is associated with obesity, hepatic steatosis and systemic inflammation. To unravel the underlying mechanisms governing the effect of feeding regimes on energy metabolism and egg production, a transcriptomics approach was carried out for screening differentially expressed genes (DEGs) in ovary, liver and adipose tissues of broiler chickens under ad libitum and restricted feeding.ResultsIt showed that 289, 388 and 204 DEGs were identified in the adipose, liver and ovary, respectively. These DEGs were significantly enriched in phagosome pathway, lipid transport, activity and nutrient reservoir activity in ovary; steroid hormone biosynthesis and metabolism of xenobiotics by cytochrome P450 pathways in adipose tissue; and the metabolic pathways, peroxisome proliferator-activated receptor (PPAR) and Jak-STAT signaling pathway in liver. Estrogen receptor 1, identified as one of important hubs by constructing PPI network, was up-regulated in ad libitum group, which would make more apolipoproteins be transferred to ovary.ConclusionsHigh expression of VTGs, APOB, CYBB and CTSS in ovary would induce excess lipid deposit, oxidative stress and potential damage to ovulation. Our results contribute to understanding effects of feeding regimes on metabolic regulation during egg production of broiler breeder hens and also provide new evidence of metabolic regulation from integrated multi-tissue processes.

Identification of a novel antisense RNA that regulates growth hormone receptor expression in chickens

ABSTRACT Natural antisense transcripts (NATs) are widely present in mammalian genomes and act as pivotal regulator molecules of gene expression. However, studies on NATs in the chicken are relatively rare. We identified a novel antisense transcript in the chicken, designated GHR-AS-EST, transcribed from the growth hormone receptor (GHR) locus, which encodes a well-known regulatory molecule of muscle development and fat deposition. GHR-AS-EST is predominantly expressed in the chicken liver and muscle tissues. GHR-AS-EST sequence conservation among vertebrates is weak. GHR-AS-EST forms an RNA–RNA duplex with GHBP to increase its stability, and regulates the expression of GHR sense transcripts at both the mRNA and protein levels. Further, GHR-AS-EST promotes cell proliferation by stimulating the expression of signaling factors in the JAK2/STAT pathway, and contributes to fat deposition via downregulating the expression of signaling factors in the JAK2/SOCS pathway in LMH hepatocellular carcinoma cells. We expect that the discovery of a NAT for a regulatory gene associated with cell proliferation and lipolysis will further our understanding of the molecular regulation of both muscle development and fat deposition.

Discovery of potential transcriptional biomarkers in broiler chicken for detection of amantadine abuse based on RNA sequencing technology

ABSTRACTThe aim of this study was to identify candidate transcriptional biomarkers so as to provide a new method for monitoring amantadine residues during the feeding of broiler chicken. RNA sequencing (RNA-seq) and bioinformatic analyses were conducted to examine the transcriptomic changes and screen differentially expressed genes (DEGs) in broiler chicken breast muscle and liver tissues treated with amantadine. The results indicated that a total of 170 DEGs were screened from broiler chicken breast muscle tissues after amantadine was fed. Among the genes, 120 were up-regulated and 50 were down-regulated. The gene ontology (GO) terms for these genes mainly existed in the areas of hydrolase activity, immune reaction and chemokine activity. The significantly enriched pathways in the Kyoto Encyclopedia for Genes and Genomes (KEGG) were in phagosomes, cell adhesion molecules (CAMs), lysosomes and extracellular matrix (ECM) receptors. From the broiler chicken liver tissues, 172 DEGs were screened, among which 116 were up-regulated and 56 were down-regulated. The GO terms of these DEGs were related to functions such as catalytic activities, metabolic activities, oxidation-reduction activities, immune reactions and cofactor binding. The significantly enriched KEGG pathways existed in metabolism, CAM, ECM receptor reaction and drug metabolism-cytochrome P450. According to the fold-change (FC), significance levels, functional annotations and possible biological processes of DEGs, 11 and 9 candidate DEGs related to amantadine treatment were further screened from broiler chicken breast muscle and liver tissues, respectively. In addition, the quantitative real-time polymerase chain reaction (qRT-PCR) verification showed exactly concordant results with the RNA-seq data. Principal components analysis (PCA) on the qRT-PCR data resulted in the separation of treated samples from the control samples in both tissues. The results provided a basis for identification of transcriptional biomarkers for detecting amantadine residues in broiler chicken breast muscle and liver tissues.

Optical Penetration Depths and Fluence Distributions in Chicken Breast and Liver Tissues-=SUP=-*-=/SUP=-

Optical Penetration Depths and Fluence Distributions in Chicken Breast and Liver Tissues-=SUP=-*-=/SUP=-

Development of chemical isotope labeling LC-MS for tissue metabolomics and its application for brain and liver metabolome profiling in Alzheimer's disease mouse model

Tissue metabolomics can play an important role in biological studies and biomarker discovery. However, high-coverage metabolome analysis of tissue samples remains a challenge. In this work, we report an analytical method for in-depth tissue metabolome profiling with highly accurate metabolite quantification. This method is based on tissue homogenization with an extraction solvent mixture of methanol, dichloromethane and water, high-performance differential chemical isotope labeling (CIL) of metabolite extracts, followed by high-resolution liquid chromatography mass spectrometry (LC-MS) detection of labeled metabolites. The method development was initially carried out using chicken liver tissue. To demonstrate the analytical performance and potential applications of this approach in real world tissue metabolomics, we examined changes in the amine/phenol submetabolome of liver and brain tissues from an Alzheimer's disease (AD) mouse model. A total of 2319 and 1769 peak pairs or amine-/phenol-containing metabolites were commonly detected in 80% of the liver samples (n = 22) and 80% of the brain samples (n = 22), respectively. In liver samples, 89 metabolites were positively identified using labeled standard library and 1063 peak pairs were putatively matched to metabolome databases, while 78 were positively identified and 753 were putatively matched in brain samples. Using multivariate and univariate analyses to study these metabolites, we observed significant metabolome differences between AD transgenic mice and wild-type mice in both liver and brain tissues, with several metabolite biomarker candidates having good discriminative power. We envisage that the CIL LC-MS method reported herein can be used in various application areas requiring in-depth analysis of tissue metabolomes.

Construction of the pEGFP-N1-p53/MAR Vector and Its Effect on HEP3B Cell Morphology

Cancer always presents a big problem that endangers human health. In recent years, the use of gene therapy in cancer research has significantly increased. This study aimed to construct a non-viral, wild-type, recombinant eukaryotic expression vector, pEGFP-N1-p53/MAR and verify its mechanism of action in cancer cells in vitro. This investigation provides a novel strategy for p53 gene therapy via regulation of the matrix attachment region (MAR), potentially laying a foundation for the establishment of an anticancer protein bioreactor. The p53 gene was cloned from human peripheral blood and the MAR gene was amplified from chicken liver tissue. The recombinant eukaryotic expression vector pEGFP-N1-p53/MAR was constructed using an E. coli self-replication system. LipofectamineTM 2000 was used as the transfection agent to deliver the plasmid into the human hepatic carcinoma (HEP3B) cell line. We divided the groups as follows: negative control cells without plasmid transfection, vehicle control cells transfected with the PEGFP-N1 vector, and experimental cells transfected with the pEGFP-N1-p53/MAR vector. Cells in each well of the vehicle control and experimental groups were transfected with 1.6 μg of plasmid and 3 μL of liposome. The cellular morphology of each group was analysed using green fluorescence microscopy at 12, 24, 36 and 48 h. Then, statistical analysis of the apoptosis rates among the three groups was performed using SPSS. The ultrastructures of the cells were observed via transmission electron microscopy after transfection for 24 h. Morphological analysis showed that the cells of the experimental group were shrunken and reduced in size and their intercellular connections had disappeared. Additionally, the apoptosis rate in the experimental group was significantly higher than that in the control groups and the cellular microstructure showed that heterochromatin and apoptotic bodies were found in the experimental group. In conclusion, compared with the control groups, the pEGFP-N1-p53/MAR plasmid can effectively promote Hep3B cell apoptosis in vitro.

T-2 mycotoxin induced apoptosis in broiler’s liver tissue

Apoptosis is a process of programmed cell death that occurs in multicellular organisms. As T-2 toxin is known to induce apoptosis in mammalian cells, the aim of the present experiment was to study the toxic effect of T-2 on chicken liver tissue using apoptosis-related antibodies p21 and p53 which are involved in the p53/p21-mediated apoptotic signalling pathway.
 The experiment was conducted on fourteen 40-day-old broilers (Gallus gallus domesticus) who were divided into control and T-2 toxin groups. For the T-2 toxin group, T-2 toxin (Sigma, Germany) was dissolved in water and given per os for three consecutive days. The material of the liver was taken 24 hours after the last application. The specimens were fixed with 10% formalin and embedded into paraffin; slices 5 μm in thickness were cut followed by immunohistochemical staining with polyclonal primary antibodies p21 and p53 (Abcam, UK) according to the manufacturer’s guidelines (IHC kit, Abcam, UK).
 Strong expression of p21 and p53 found in hepatocytes, endotheliocytes and around blood vessels together with large tissue destructions in T-2 toxin group birds’ liver indicates apoptosis and histopathological changes in liver tissue during T-2 mycotoxicosis.

Development of nested multiplex polymerase chain reaction (PCR) assay for the detection of Toxocara canis, Toxocara cati and Ascaris suum contamination in meat and organ meats

Ascarid Larva Migrans Syndrome (ascarid LMS) is a clinical syndrome in humans, caused by the migration of animal roundworm larvae such as Toxocara canis, Toxocara cati and Ascaris suum. Humans may acquire infection by ingesting embryonated eggs, or infective larvae of these parasites in contaminated meat and organ meats. To detect these pathogenic contaminations, a novel nested multiplex PCR system was developed. Our novel nested multiplex PCR assay showed specific amplification of T. canis, T. cati and Ascaris spp. Detection limit of the nested multiplex PCR was tested with serial dilution of T. canis, T. cati or A. suum genomic DNA (gDNA) from 100 pg to 100 ag and found to be 10 fg, 1 fg and 100 fg, respectively. When larvae were spiked into chicken liver tissue, DNA of T. canis and A. suum was detected from the liver spiked with a single larva, while the assay required at least 2 larvae of T. cati. Moreover, the ascarid DNA was detected from the liver of mice infected with 100 and 300 eggs of T. canis, T. cati or A. suum. This nested multiplex PCR assay could be useful for the detection of contamination with ascarid larvae in meat and organ meats.

Effect of Zinc Sulfate and Zinc Glycine Chelate on Concentrations of Acute Phase Proteins in Chicken Serum and Liver Tissue

The aim of the study was to determine how inorganic and organic forms of zinc affect the concentrations of C-reactive protein (CRP), serum amyloid A (SAA), alpha-1-acid glycoprotein (α-1-AGP), haptoglobin (Hp), and transferrin (TRF) in the blood and liver tissue of 450 1-day-old Ross 308 chicken. Four experimental groups received one the following: inorganic zinc (ZnSO4), a zinc phytase enzyme supplement (ZnSO4-F), organic zinc in combination with glycine (Zn-Gly), or organic zinc supplemented with phytase (Zn-Gly-F). The chicken serum and liver homogenates were assayed using an ELISA kit. The results of the study showed statistically significantly higher serum and liver concentration of SAA in the group of birds that received zinc sulfate in comparison to the group of birds receiving zinc in organic form. A statistically significantly higher serum concentration of CRP and α-1-AGP was also noted in the group receiving zinc sulfate as compared to the Zn-Gly group. Comparison of the serum concentration of TRF between the supplemented groups showed a statistically significant increase in this parameter in the Zn-Gly-F group as compared to the ZSO4-F group. The increase in the serum concentration of Hp in all groups in comparison to the control may indicate stimulation of local immune mechanisms. The results of this study showed an increase in the concentrations of APPs such as AGP and TRF following the administration of zinc glycine chelates, which may demonstrate their effect on metabolic processes in the liver and on immunocompetent cells that regulate the intensity of the immune response.

Ameliorative effects of nano-elemental selenium against hexavalent chromium-induced apoptosis in broiler liver

The current study examined the ameliorative effects of nano-elemental selenium (Nano-Se) against chromium-VI (K2Cr2O7)-induced apoptosis in chickens. The expression of apoptosis-related genes was evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot. A total of 60, one-day-old broiler chickens allotted to six equal groups, i.e., control group (standard diet), Cr(VI)-exposed group (K2Cr2O7 via drinking water), Nano-Se group (Nano-Se at 0.5mg/kg via diet), protection group (K2Cr2O7 + Nano-Se), cure group (K2Cr2O7 for initial 2weeks and then Nano-Se), and prevention group (opposite to the cure group) and were detected by the activities of pro-apoptosis (Bax, Caspase-3) and anti-apoptosis (Bcl-2) genes expression at day 35 of the experiment. Intense apoptosis was observed in liver tissues of chickens exposed to K2Cr2O7. The Nano-Se supplementation caused a significant decrease (P < 0.01) in the mRNA expression levels of Bax and Caspase-3 genes, while significantly elevated (P< 0.05) mRNA expression level of Bcl-2 gene was observed in Nano-Se experimental groups as compare to control and Cr(VI)-exposed group. The results quantified by the RT-qPCR were further confirmed by the western blot analysis. Altogether, these results suggest anti-apoptotic effects of Nano-Se in the chicken liver, which is interesting for further study. The present findings suggested that Nano-Se has protective effects against K2Cr2O7-induced apoptosis in broilers liver and can serve a key role as a protective agent against apoptosis.

Development of a UPLC-FLD Method for Detection of Aflatoxin B1 and M1 in Animal Tissue to Study the Effect of Curcumin on Mycotoxin Clearance Rates.

Aflatoxin B1 (AFB1) and its metabolite aflatoxin M1 (AFM1) are well-known carcinogens for humans and animals health. In this study, an ultra-high performance liquid chromatography linked with fluorescence detection (UPLC-FLD) method was optimized and validated. In addition, we investigated for the first time, the influence of curcumin on residue depletion of AFB1 and AFM1 in liver, kidney, and muscle tissues of broiler chickens and estimated a necessary clearance time required for AFB1 and AFM1 residues. The results showed that the average recoveries of AFB1 varied in liver, kidney, and muscles between 82.32–85.56, 85.34–88.45, and 84.88–89.73% respectively, while the average recoveries of AFM1 in liver, kidney, and muscles varied between 92.17–95.03, 94.12–97.21, and 95.32–98.51%, respectively. The detection limit of aflatoxin B1 was 0.008 ng/ml, while for aflatoxin M1 was 0.003 ng/ml. The limit of quantification (LOQ) for AFB1 and AFM1 was 0.02 and 0.01 ng/ml, respectively. Clearance time for AFB1 and AFM1 residues were analyzed in two experimental groups of broilers. One group fed with dietary AFB1 (5.0 mg/kg feed) and other with curcumin+AFB1 diet (curcumin; 300 mg/kg feed, AFB1; 5.0 mg/kg feed). AFB1 and AFM1 residues clearance time was calculated based on LOQ using withdrawal time calculation software (WT1.4). Clearance time analyzed for AFB1 ranged from 11 to 19 days and for AFM1 ranged from 10 to 12 days at 95% confidence level. Interestingly, curcumin supplementation in the diet reduced the clearance time of AFM1 in liver and kidney but not in muscle tissues. Conclusively, the developed method can be appropriately used for the quality control testing of commercial broiler-meat processing companies, food manufacturers, and quality control laboratories.

Microcystin-leucine-arginine Modulates the Expression Patterns of Proinflammatory Cytokines and an Apoptotic Gene in Chicken Liver.

Microcystins (MCs) are included in drinking water and a family of cyclic heptapeptide hepatotoxins that have been implicated in the impairment of liver function in various animals. There is scarce information on the effect of MCs on cytokines and apoptotic gene expression and on whether MCs can induce inflammation and apoptosis in avian hepatic tissue. This study investigated the expression of genes related to proinflammatory interleukins, apoptosis, and antioxidant function in chicken liver tissues cultured in the presence of different doses of microcystin-leucine-arginine (MC-LR). Livers were collected from five hens and liver slices were placed in sterile tubes containing Dulbecco's medium supplemented with 0, 1, 10, or 100 ng/mL of MC-LR. After 6 h of cultivation, total RNA was extracted and quantitative PCR analysis was performed for interleukin genes (IL-1β, IL-6, and IL-8), TNF sf15, an apoptotic gene (caspase-3), and genes involved in antioxidant function ([catalase [CAT ], glutathione peroxidase [GSH-PX ], and superoxide dismutase [SOD]). Liver tissues in each group were fixed for histopathology. MC-LR downregulated the mRNA levels of IL-1β, IL-8, and TNF sf15 as compared to the control (0 ng/mL) in dose-dependent patterns; however, the differences were not significant. The expression of IL-6 in liver tissues exposed to 100 ng/mL of MC-LR was significantly (P<0.05) lower than that in tissues exposed to 1 ng/mL. In contrast, MC-LR upregulated the mRNA expression of caspase-3 and genes involved in antioxidant function in the liver tissues after 6 h, without the difference reaching statistical significance. Hepatocytes showed vacuolar degeneration and focal necrosis according to the dose of MC-LR. This study highlighted the risk of low doses of MC-LR in chicken liver. Moreover, MC-LR could modulate the transcriptional patterns of at least IL-6 in liver-tissue culture of chicken after 6 h of exposure.

Rapid multiresidue determination of pesticides in livestock muscle and liver tissue via modified QuEChERS sample preparation and LC-MS/MS

ABSTRACTMany multiresidue methods for the determination of pesticides in vegetables and fruits have been reported to date. However, few such methods have been employed to investigate pesticide residues in animal tissue. In this study, an LC-MS/MS multiresidue method coupled with modified QuEChERS extraction was developed and validated for the investigation of eight pesticide residues: prallethrin (PR), resmethrin (RMT), imidacloprid (IMC), diflubenzuron (DFB), cyromazine (CYR), etofenprox (EFP), dinotefuran (DNT) and phthalthrin (PTLT). This method involves initial extraction in a water/acetone system, the addition of salts and a subsequent extraction/partitioning step and, finally, a clean-up step utilising dispersive solid-phase extraction (SPE). The mean recoveries of seven of the pesticides (the exception being CYR) ranged between 74.7% and 113.5%, and the CVs of the livestock tissue – bovine, swine, and chicken muscle and liver tissue spiked at 10 ng g–1 (50 ng g–1 for RMT and DNT) and 100 ng g–1 – were < 13.8%. The recoveries of CYR in all muscle and liver spiked samples ranged from 56.9% to 78.3%, while those of RMT in swine liver were > 120%. Therefore, this method was considered as being unsuitable for the investigation of these samples. The limits of quantitation (LOQs) of seven of the investigated pesticides (the exception being swine liver) in the tissue samples ranged from 0.9 to 15.2 ng g–1. We therefore concluded that this LC-MS/MS multiresidue method is a valid and suitable for the investigation of seven pesticides in animal tissue, but it is unsuitable for the analysis of CYR in all animal tissues and RMT in swine liver tissue.

Long noncoding RNA repertoire in chicken liver and adipose tissue

BackgroundImproving functional annotation of the chicken genome is a key challenge in bridging the gap between genotype and phenotype. Among all transcribed regions, long noncoding RNAs (lncRNAs) are a major component of the transcriptome and its regulation, and whole-transcriptome sequencing (RNA-Seq) has greatly improved their identification and characterization. We performed an extensive profiling of the lncRNA transcriptome in the chicken liver and adipose tissue by RNA-Seq. We focused on these two tissues because of their importance in various economical traits for which energy storage and mobilization play key roles and also because of their high cell homogeneity. To predict lncRNAs, we used a recently developed tool called FEELnc, which also classifies them with respect to their distance and strand orientation to the closest protein-coding genes. Moreover, to confidently identify the genes/transcripts expressed in each tissue (a complex task for weakly expressed molecules such as lncRNAs), we probed a particularly large number of biological replicates (16 per tissue) compared to common multi-tissue studies with a larger set of tissues but less sampling.ResultsWe predicted 2193 lncRNA genes, among which 1670 were robustly expressed across replicates in the liver and/or adipose tissue and which were classified into 1493 intergenic and 177 intragenic lncRNAs located between and within protein-coding genes, respectively. We observed similar structural features between chickens and mammals, with strong synteny conservation but without sequence conservation. As previously reported, we confirm that lncRNAs have a lower and more tissue-specific expression than mRNAs. Finally, we showed that adjacent lncRNA-mRNA genes in divergent orientation have a higher co-expression level when separated by less than 1 kb compared to more distant divergent pairs. Among these, we highlighted for the first time a novel lncRNA candidate involved in lipid metabolism, lnc_DHCR24, which is highly correlated with the DHCR24 gene that encodes a key enzyme of cholesterol biosynthesis.ConclusionsWe provide a comprehensive lncRNA repertoire in the chicken liver and adipose tissue, which shows interesting patterns of co-expression between mRNAs and lncRNAs. It contributes to improving the structural and functional annotation of the chicken genome and provides a basis for further studies on energy storage and mobilization traits in the chicken.

Quantifying tissue viscoelasticity using optical coherence elastography and the Rayleigh wave model.

This study demonstrates the feasibility of using the Rayleigh wave model (RWM) in combination with optical coherence elastography (OCE) technique to assess the viscoelasticity of soft tissues. Dispersion curves calculated from the spectral decomposition of OCE-measured air-pulse induced elastic waves were used to quantify the viscoelasticity of samples using the RWM. Validation studies were first conducted on 10% gelatin phantoms with different concentrations of oil. The results showed that the oil increased the viscosity of the gelatin phantom samples. This method was then used to quantify the viscoelasticity of chicken liver. The Young’s modulus of the chicken liver tissues was estimated as E=2.04±0.88??kPa with a shear viscosity ?=1.20±0.13??Pa?s. The analytical solution of the RWM correlated very well with the OCE-measured phased velocities (R2=0.96±0.04). The results show that the combination of the RWM and OCE is a promising method for noninvasively quantifying the biomechanical properties of soft tissues and may be a useful tool for detecting disease.

Accumulation of polybrominated diphenyl ethers in the brain compared with the levels in other tissues among different vertebrates from an e-waste recycling site

This study aimed to investigate the accumulation of polybrominated diphenyl ethers (PBDEs) in the brain compared with that in other tissues among different vertebrates. We collected mice, chickens, ducks, frogs, and fish from an e-waste recycling region in Taizhou, China, and measured PBDE concentrations in brain, liver and muscle tissues. The levels of PBDE in the tissues of mice, chickens, ducks, frogs and fish ranged 0.45–206, 0.06–18.8, 1.83–112, 2.75–108, and 0.02–32.0 ng/g wet weight, respectively. Preferential distribution in the liver and muscle relative to the brain was observed for PBDEs in mice, chickens, ducks and frogs. However, a high retention in the brain compared to the liver and muscle was observed in fish. Comparison of the brain/liver concentration (B/L) ratios revealed differences in PBDEs accumulation in the brain among these vertebrates. PBDEs accumulation in the brain was greatest in fish, followed by frogs, while the lowest accumulation occurred in the brains of mammals and birds. The findings apparently coincided with the evolution of the blood-brain barrier (BBB) across vertebrates, i.e. the BBB of fish might be less efficient than those of mammals, birds and amphibian. Low brominated congeners (such as BDE-28, BDE-47 and BDE-99) were predominant in the brains of investigated vertebrates, whereas BDE-209 was most abundant in liver and muscle tissues of mice, chickens and ducks. Significant differences in B/L ratios among PBDE congeners were found in both mice and chickens (p < 0.05). Particularly in mice, the B/L ratios of PBDE congeners presented a declining trend with increased bromine number. Our findings suggested that low brominated congeners might have a higher capacity to penetrate the BBB and accumulate in the brain, whereas high brominated congeners such as BDE-209 might have less potency to pass through the barrier. Further experimental studies are needed to confirm our findings.