Auricularia auricula Anionic Polysaccharide Nanoparticles for Gastrointestinal Delivery of Pinus koraiensis Polyphenol Used in Bone Protection under Weightlessness.

Auricularia auricula polysaccharides used in Pinus koraiensis polyphenol encapsulation and delivery under weightlessness are rarely reported. In this study, an anionic polysaccharide fragment named AAP Iα with a molecular weight of 133.304 kDa was isolated and purified to construct a polyphenol encapsulation system. Nanoparticles named NPs-PP loaded with a rough surface for Pinus koraiensis polyphenol (PP) delivery were fabricated by AAP Iα and ε-poly-L-lysine (ε-PL). SEM and the DLS tracking method were used to observe continuous changes in AAP Iα, ε-PL and PP on the nanoparticles' rough surface assembly, as well as the dispersion and stability. Hydrophilic, monodisperse and highly negative charged nanoparticles can be formed at AAP Iα 0.8 mg/mL, ε-PL 20 µg/mL and PP 80 µg/mL. FT-IR was used to determine their electrostatic interactions. Release kinetic studies showed that nanoparticles had an ideal gastrointestinal delivery effect. NPs-PP loaded were assembled through electrostatic interactions between polyelectrolytes after hydrogen bonding formation in PP-AAP Iα and PP-ε-PL, respectively. Colon adhesion properties and PP delivery in vivo of nanoparticles showed that NPs-PP loaded had high adhesion efficiency to the colonic mucosa under simulated microgravity and could enhance PP bioavailability. These results suggest that AAP Iα can be used in PP encapsulation and delivery under microgravity in astronaut food additives.

Transcriptome Revealed Exposure to the Environmental Ammonia Induced Oxidative Stress and Inflammatory Injury in Spleen of Fattening Pigs.

Ammonia is one of the major environmental pollutants that seriously threaten human health. Although many studies have shown that ammonia causes oxidative stress and inflammation in spleen tissue, the mechanism of action is still unclear. In this study, the ammonia poisoning model of fattening pigs was successfully established. We examined the morphological changes and antioxidant functions of fattening pig spleen after 30-day exposure to ammonia. Effects of ammonia in the fattening pig spleen were analyzed from the perspective of oxidative stress, inflammation, and histone methylation via transcriptome sequencing technology (RNA-seq) and real-time quantitative PCR validation (qRT-PCR). We obtained 340 differential expression genes (DEGs) by RNA-seq. Compared with the control group, 244 genes were significantly upregulated, and 96 genes were significantly downregulated in the ammonia gas group. Some genes in Gene Ontology (GO) terms were verified and showed significant differences by qRT-PCR. The KEGG pathway revealed significant changes in the MAPK signaling pathway, which is strongly associated with inflammatory injury. To sum up, the results indicated that ammonia induces oxidative stress in pig spleen, activates the MAPK signaling pathway, and causes spleen necrosis and injury. In addition, some differential genes encoding epigenetic factors were found, which may be involved in the response mechanism of spleen tissue oxidative damage. The present study provides a transcriptome database of ammonia-induced spleen poisoning, providing a reference for risk assessment and comparative medicine of ammonia.

AMPK/PPAR-γ/NF-κB axis participates in ROS-mediated apoptosis and autophagy caused by cadmium in pig liver.

The experiment was conducted to investigate the effects of Cadmium (Cd) on growth performance, blood biochemical parameters, oxidative stress, hepatocyte apoptosis and autophagy of weaned piglets. A total of 12 healthy weaned piglets were randomly assigned to the control and the Cd group, which were fed with a basal diet and the basal diet supplemented with 15 ± 0.242 mg/kg CdCl2 for 30 d, respectively. Our results demonstrated that Cd significantly decreased final body weight, average daily feed intake (ADFI), average daily gain (ADG) and increased feed-to-gain (F/G) ratio (P < 0.05). For blood biochemical parameters, Cd treatment significantly decreased the red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), total protein, albumin, copper content and iron content (P < 0.05). In addition, liver injury was observed in the Cd-exposed group. Our results also demonstrated that Cd exposure contributed to the production of ROS, activated the AMPK/PPAR-γ/NF-κB pathway (increasing the expressions of P-AMPK/AMPK, NF-κB, I-κB-ß, COX-2, and iNOS, decreasing the expressions of PPAR-γ and I-κB-α), finally induced autophagy (increasing the expressions of Beclin-1, the ratio of LC3-II/LC3-I and p62), and apoptosis (increasing the expressions of Bax, Bak, Caspase-9, and Caspase-3, decreasing the expression of Bcl-2). Overall, these findings revealed the vital role of AMPK/PPAR-γ/NF-κB pathway in Cd-induced liver apoptosis and autophagy, which provided deeper insights into a better understanding of Cd-induced hepatotoxicity.

Ammonia exposure causes the imbalance of the gut-brain axis by altering gene networks associated with oxidative metabolism, inflammation and apoptosis.

Ammonia is an acknowledged environment pollutant in atmosphere with irritating smell. Previous studies have shown that excessive ammonia has toxic effects on farm animals and humans. However, the detail toxicity mechanism of ammonia to pigs is still unknown so far. In order to clarify the mechanism of ammonia toxicity, we established a porcine exogenous ammonia poisoning model and assessed the effects of ammonia on the gut-brain axis by transcriptome sequencing, histological observation and chemical analysis. Our results showed that after 30 d of ammonia exposure, 578 differentially expressed genes (DEGs) and 407 DEGs were obtained in the hypothalamus and jejunum, respectively. These DEGs were enriched into Gene Ontology terms associated with inflammation, oxidative metabolism, apoptosis, and the highly expressed genes among these DEGs were verified by real-time quantitative PCR. The content of glutathione and the activities of glutathione peroxidase and superoxide dismutase were significantly decreased, while malondialdehyde content was increased after ammonia exposure. Corticotropin releasing factor, substance P, 5-hydroxytryptamine and ghrelin contents in serum elevated significantly. Furthermore, pathologic observation in the ammonia group revealed infiltration of lymphocytes in the hypothalamus and significant decrease of jejunal epithelial cells. Our results indicated that ammonia exposure mediated changes in transcriptional profiles, pathological damage, oxidative stress and brain-gut peptide of the pig jejunum and hypothalamus, and induced the imbalance of the brain-gut axis through the "oxidative stress-inflammation-apoptosis" interaction network. Our study not only provides a new perspective for the toxicity assessment of ammonia, but also enriches the toxicology mechanism of ammonia.

Effects of music stimulus on behavior response, cortisol level, and horizontal immunity of growing pigs.

An enriched environment is widely used to improve domestic animals' welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.

Excessive ammonia inhalation causes liver damage and dysfunction by altering gene networks associated with oxidative stress and immune function.

Ammonia (NH3) is a major gaseous pollutant in livestock production and has adverse effects on production, health and welfare of animals. The liver is one of the target organs of NH3, and excessive NH3 inhalation can induce liver damage. However, the toxicity assessment of NH3 on pig liver and its mechanism have not been reported yet. Recently, transcriptome analysis has become a major method to study the toxic mechanism of pollutants in environmental toxicology. Therefore, in the present study, we examined the effects of excessive NH3 inhalation on the liver of fattening pig through chemical analysis, ELISA, transcriptome analysis and real-time quantitative PCR (qRT-PCR). Our results showed that the transcriptome analysis database of fattening pig liver under excessive NH3 exposure, and 449 differentially expressed genes (DEGs) (including 181 up-regulated DEGs and 168 down-regulated DEGs) were found. Some genes associated with the 3 Gene Ontology (GO) terms (liver function, immune, antioxidant defense) were validated by quantitative real-time PCR. In addition, the activities of GPT and GOT in NH3 group were significantly increased by 63.5% and 37.4% (P < 0.05), respectively. Our results indicated that NH3 exposure could cause changes in transcriptional profiles and liver function, and induce liver damage in fattening pigs through oxidative stress and immune dysfunction. Our study results not only provide a new perspective for the toxicity assessment of NH3, but also enrich the toxicological mechanism of NH3.

Ammonia exposure induces oxidative stress and inflammation by destroying the microtubule structures and the balance of solute carriers in the trachea of pigs.

Ammonia (NH3) is the most alkaline gaseous compound in the atmosphere and the primary gas pollutant in the piggery. It can cause irritation and damage to the airway after inhalation. However, the effects and toxicity mechanism of NH3 on the trachea are still unclear. In order to evaluate the toxic effects of NH3 inhalation on pig trachea, the changes of oxidative stress parameters (SOD, GSH, GSH-Px, and MDA), tissue structure and transcriptome in the trachea of pigs were examined after 30 days of exposure to NH3. Our results showed SOD, GSH-Px and GSH in the trachea in the NH3-treatment group were significantly decreased (P < 0.05) compared with the control group, on the contrary, MDA content was significantly higher (P < 0.05). The analysis of differentially expressed genes (DEGs) showed that 2542 DEGs (1109 up-regulated DEGs and 1433 down-regulated DEGs) were significantly changed under NH3 exposure, including many DEGs associated with inflammation, oxidative stress, microtubule activity and SLC family, and the qRT-PCR verification results of these DEGs were consistent with the transcriptome results. The results indicated that NH3 exposure could break down the mucosal barrier of the respiratory tract, induce oxidative stress and inflammation, reduce the activity of microtubules and disrupt the balance of SLC transporters. In this study, transcriptome analysis was used for the first time to explore the toxic mechanism of NH3 on pig trachea, providing new insights for better assessing the toxicity mechanism of NH3, as well as references for comparative medicine.

Exposure to the environmental pollutant ammonia causes changes in gut microbiota and inflammatory markers in fattening pigs.

Ammonia (NH3) is a major pollutant in livestock houses and atmospheric environment. It has been demonstrated that NH3 can cause a series of damage to animals and human. However, toxicity evaluation of NH3 on farm animals was rarely reported, especially in the intestinal microflora. Therefore, in this study, twenty-four 125-day-old fattening pigs were randomly divided into 4 groups: control group, NH3 group (88.2 mg m-3 < NH3 concentration < 90.4 mg m-3), Se group (Se content: 0.5 mg kg-1), and NH3 + Se group (88.2 mg m-3 < NH3 concentration < 90.4 mg m-3, Se content: 0.5 mg kg-1), and the effects of NH3 and L-Selenomethionine on the microbiota composition in the jejunum and the levels of inflammatory markers in feces of fattening pigs were examined by 16S rDNA and ELISA, respectively. Our results showed that the content of Matrix metalloproteinase-9 (MMP-9), Myeloperoxidase (MPO), Lactoferrin (LTF) and Calprotectin in the ammonia group (A group) were significantly elevated compared to the control group, and the content of MMP-9, MPO, LTF and Calprotectin in the A + Se group were significantly reduced. A significant difference in microbiota composition in the phylum, class, family and genus levels was found in the A group and the NH3 + Se group. There was a negative correlation between Streptococcus and Calprotectin. Our results indicated that excessive NH3 inhalation could cause changes in inflammatory markers and beta diversity of intestinal microflora in fattening pigs. We found there was a positive correlation between MPO and Pseudomonas. In addition, we first proposed that L-Selenomethionine could improve the imbalance of microbial flora and the inflammatory injury caused by NH3. Changes in intestinal microflora and inflammatory markers can be used as important indicators to evaluate NH3 toxicity, and studying changes in intestinal microflora is also an important mechanism to reveal NH3 toxicity.