Enhanced hepatotoxicity in zebrafish due to co-exposure of microplastics and sulfamethoxazole: Insights into ROS-mediated MAPK signaling pathway regulation.

The combined pollution of microplastics (MPs) and sulfamethoxazole (SMZ) often occurs in aquatic ecosystems, posing a serious threat to animal and human health. However, little is known about the liver damage caused by the single or co-exposure of MPs and SMZ, and its specific mechanisms are still poorly understood. In this study, we investigated the effects of co-exposure to 20 µm or 80 nm MPs and SMZ in both larval and adult zebrafish models. Firstly, we observed a significant decrease in the number of hepatocytes and the liver damage in larval zebrafish worsened following co-exposure to SMZ and MPs. Additionally, the number of macrophages and neutrophils decreased, while the expression of inflammatory cytokines and antioxidant enzyme activities increased after co-exposure in larval zebrafish. Transcriptome analysis revealed significant changes in gene expression in the co-exposed groups, particularly in processes related to oxidation-reduction, inflammatory response, and the MAPK signaling pathway in the liver of adult zebrafish. Co-exposure of SMZ and MPs also promoted hepatocyte apoptosis and inhibited proliferation levels, which was associated with the translocation of Nrf2 from the cytoplasm to the nucleus and an increase in protein levels of Nrf2 and NF-kB p65 in the adult zebrafish. Furthermore, our pharmacological experiments demonstrated that inhibiting ROS and blocking the MAPK signaling pathway partially rescued the liver injury induced by co-exposure both in larval and adult zebrafish. In conclusion, our findings suggest that co-exposure to SMZ and MPs induces hepatic dysfunction through the ROS-mediated MAPK signaling pathway in zebrafish. This information provides novel insights into the potential environmental risk of MPs and hazardous pollutants co-existence in aquatic ecosystems.

Subchronic co-exposure of polystyrene nanoplastics and 3-BHA significantly aggravated the reproductive toxicity of ovaries and uterus in female mice.

Both nanoplastics (NPs) and 3-tert-butyl-4-hydroxyanisole (3-BHA) are environmental contaminants that can bio-accumulate through the food chain. However, the combined effects of which on mammalian female reproductive system remain unclear. Here, the female ICR-CD1 mice were used to evaluate the damage effects of ovaries and uterus after NPs and 3-BHA co-treatment for 35 days. Firstly, co-exposure significantly reduced the body weight and organ index of ovaries and uterus in mice. Secondly, combined effects of NPs and 3-BHA exacerbated the histopathological abnormalities to the ovaries and uterus and decreased female sex hormones such as FSH and LH while increased antioxidant activities including CAT and GSH-Px. Moreover, the apoptotic genes, inflammatory cytokines and the key reproductive development genes such as FSTL1 were significantly up-regulated under co-exposure conditions. Thirdly, through transcriptional and bioinformatics analysis, immunofluorescence and western blotting assays, together with molecular docking simulation, we determined that co-exposure up-regulated the FSTL1, TGF-ß and p-Smad1/5/9 but down-regulated the expression of BMP4. Finally, the pharmacological rescue experiments further demonstrated that co-exposure of NPs and 3-BHA mainly exacerbated the female reproductive toxicity through FSTL1-mediated BMP4/TGF-ß/SMAD signaling pathway. Taken together, our studies provided the theoretical basis of new environmental pollutants on the reproductive health in female mammals.

Dietary Betaine Improves Glucose Metabolism in Obese Mice.

BACKGROUND: Obesity caused by the overconsumption of energy-dense foods high in fat and sugar has contributed to the growing prevalence of type 2 diabetes. Betaine, found in food or supplements, has been found to lower blood glucose concentrations, but its exact mechanism of action is not well understood. OBJECTIVES: A comprehensive evaluation of the potential mechanisms by which betaine supplementation improves glucose metabolism. METHODS: Hyperglycemic mice were fed betaine to measure the indexes of glucose metabolism in the liver and muscle. To explore the mechanism behind the regulation of betaine on glucose metabolism, Ribonucleic Acid-Seq was used to analyze the livers of the mice. In vitro, HepG2 and C2C12 cells were treated with betaine to more comprehensively evaluate the effect of betaine on glucose metabolism. RESULTS: Betaine was added to the drinking water of high-fat diet-induced mice, and it was found to reduce blood glucose concentrations and liver triglyceride concentrations without affecting body weight, confirming its hypoglycemic effect. To investigate the specific mechanism underlying its hypoglycemic effect, protein-protein interaction enrichment analysis of the liver revealed key nodes associated with glucose metabolism, including cytochrome P450 family activity, insulin sensitivity, glucose homeostasis, and triglyceride concentrations. The Kyoto Encyclopedia of Genes and Genomes and gene ontogeny enrichment analyses showed significant enrichment of the Notch signaling pathway. These results provided bioinformatic evidence for specific pathways through which betaine regulates glucose metabolism. Key enzyme activities involved in glucose uptake, glycogen synthesis, and glycogenolysis pathways of the liver and muscle were measured, and improvements were observed in these pathways. CONCLUSIONS: This study provides new insight into the mechanisms by which betaine improves glucose metabolism in the liver and muscle and supports its potential as a drug for the treatment of metabolic disorders related to glucose.

Effects of environmental factors on avian communities in urban parks in small- to medium-sized city: a case study of Fuyang City, Anhui, China.

With a worldwide expansion of urbanization, the conservation of urban biodiversity is attracting growing attention; it is important to study the relationship between wildlife and urban green spaces. In this study, we selected 31 parks in the urban area of Fuyang City in the North China Plain. A total of 8795 individual birds from 69 species were recorded. The study found that (a) at the local level, tree diversity and heights are the most important factors contributing to each level of bird diversity, followed by the coverage of shrubs and herbs, and (b) at the landscape level, the proportion of woodland has a strong positive correlation with the multidimensional diversity of birds, followed by the patch diversity and percent of grassland. Our results showed that artificial greenland can effectively increase bird diversity. While considering urban planning and human well-being, the proportion of vegetation and landscape in urban parks should be properly planned, providing more habitats to enrich bird diversity.

Buffalo long non-coding RNA gene11007 promotes myoblasts proliferation.

Buffalo meat is of good quality because it is lean and tender, and could bring significant cardiovascular benefits. The underlying difference in muscle development and meat quality is a complex and precisely orchestrated process which has been demonstrated to be regulated by long non-coding RNAs (lncRNAs). However, the regulatory role of lncRNAs in the growth and development of buffalo skeletal muscle is still unclear. In this study, the Ribo-Zero RNA-Seq method was used to explore the lncRNA expression profiles of buffalo myoblasts during the proliferation and differentiation phases. A specific set of 9,978 lncRNAs was found. By comparing the expression profiles of lncRNAs, it was found that there were 1,576 differentially expressed lncRNAs (DELs) during buffalo myoblast differentiation. Twelve DELs were chosen and subsequently verified in eight different buffalo tissues during fetal and adult stages by using qPCR. Gene11007 was found to be one of the most down-regulated lncRNAs during buffalo myoblasts differentiation and it was subsequently characterized. EdU, CCK-8, qPCR and western blotting assays showed that gene11007 promoted the proliferation of buffalo myoblasts but it had no effect on cell differentiation. Our research may enrich the genome annotations of buffalo and provide a new molecular target for the in-depth understanding of the regulation of lncRNAs in skeletal muscle.

Discovery of Differentially Expressed MicroRNAs in Porcine Ovaries With Smaller and Larger Litter Size.

The number of live births in a litter is an important reproductive trait, and is one of the main indicators which reflect the production level and economic benefit of a pig farm. The ovary is an important reproductive organ of the sow, and it undergoes a series of biological processes during each estrous cycle. A complex transcriptional network containing coding and non-coding RNAs in the ovary closely regulates the reproductive capability of sows. However, the molecular regulation mechanisms affecting sow litter size are still unclear. We investigated the expression profiles of microRNAs (miRNAs) in porcine ovaries from sows with smaller than average litter sizes (SLS) and those with larger litter sizes (LLS). In total, 411 miRNAs were identified, and of these 17 were significantly down-regulated and 16 miRNAs were up-regulated when comparing sows with LLS and SLS, respectively. We further characterized the role of miR-183 which was one of the most up-regulated miRNAs. CCK-8, EdU incorporation and western blotting assays demonstrated that miR-183 promoted the proliferation of granulosa cells (GCs) in pig ovaries. Moreover, miR-183 inhibited the synthesis of estradiol in GCs and promoted the synthesis of progesterone. These results will help in gaining understanding of the role of miRNAs in regulating porcine litter size.

Translatomics Probes Into the Role of Lycopene on Improving Hepatic Steatosis Induced by High-Fat Diet.

Liver is an important organ for fat metabolism. Excessive intake of a high-fat/energy diet is a major cause of hepatic steatosis and its complications such as non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. Supplementation with lycopene, a natural compound, is effective in lowering triglyceride levels in the liver, although the underlying mechanism at the translational level is unclear. In this study, mice were fed a high-fat diet (HFD) to induce hepatic steatosis and treated with or without lycopene. Translation omics and transcriptome sequencing were performed on the liver to explore the regulatory mechanism of lycopene in liver steatosis induced by HFD, and identify differentially expressed genes (DEGs). We identified 1,358 DEGs at the translational level. Through transcriptomics and translatomics joint analysis, we narrowed the range of functional genes to 112 DEGs and found that lycopene may affect lipid metabolism by regulating the expression of LPIN1 at the transcriptional and translational levels. This study provides a powerful tool for translatome and transcriptome integration and a new strategy for the screening of candidate genes.

Lipidomic and Transcriptomic Analysis of the Longissimus Muscle of Luchuan and Duroc Pigs.

Meat is an essential food, and pork is the largest consumer meat product in China and the world. Intramuscular fat has always been the basis for people to select and judge meat products. Therefore, we selected the Duroc, a western lean pig breed, and the Luchuan, a Chinese obese pig breed, as models, and used the longissimus dorsi muscle for lipidomics testing and transcriptomics sequencing. The purpose of the study was to determine the differences in intramuscular fat between the two breeds and identify the reasons for the differences. We found that the intramuscular fat content of Luchuan pigs was significantly higher than that of Duroc pigs. The triglycerides and diglycerides related to flavor were higher in Luchuan pigs compared to Duroc pigs. This phenotype may be caused by the difference in the expression of key genes in the glycerolipid metabolism signaling pathway.

Genomic characteristics and pathogenicity of a new recombinant strain of porcine reproductive and respiratory syndrome virus.

Recombination is an important phenomenon that accelerates evolution and enriches the genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV). Recombinant PRRSV isolates sometimes have different genetic backgrounds. In this study, we report a recombinant PRRSV (SD-YL1712) isolated from a pig farm. The genome of SD-YL1712 is 15,014 nucleotides in length, and its nucleotide and amino acid sequence conservation is higher than that of PRRSV strain JXA1 except within the NSP2 region. The NSP2 region of SDYL1712 shares the highest nucleotide (85.9%) and amino acid (84.1%) sequence identity with PRRSV strain NADC30. SD-YL1712 was found to contain a characteristic 131-amino-acid deletion in the NSP2 region. Two recombination breakpoints were detected at nt 2134 and nt 3958 within the NSP2 region, which revealed that SD-YL1712 originated from a recombination event between NADC30-like and HP-PRRSV-derived MLV-like strains. Interestingly, SD-YL1712 had an additional deletion at position 586, similar to that found in strain TJnh1501. Moreover, the pathogenicity of strain SD-YL1712 was found to be similar to that of HP-PRRSV JXA1, which was higher than that of the CH1a strain. Further analysis indicated that SD-YL1712 might be a transitional intermediate in the evolution of TJbd1401 to TJnh1501.

Effects of lycopene on skeletal muscle-fiber type and high-fat diet-induced oxidative stress.

Increasing studies report that many natural products can participate in formation of muscle fibers. This study aimed to investigate the effect of lycopene on skeletal muscle-fiber type in vivo and in vitro. C2C12 myoblasts were used in vitro study, and the concentration of lycopene was 10 µM. In vivo, 8-week-old male C57/BL6 mice were used and divided into four groups (n=8): (1) ND: normal-fat diet; (2) ND+Lyc: normal-fat diet mixed with 0.33% w/w lycopene; (3) HFD: high-fat diet; and (4) HFD+Lyc: high-fat diet mixed with 0.33% w/w lycopene. The mice tissue samples were collected after 8 weeks feeding. We found that lycopene supplementation enhanced the protein expression of slow-twitch fiber, succinate dehydrogenase, and malic dehydrogenase enzyme activities, whereas lycopene reduced the protein expression of fast-twitch fibers, lactate dehydrogenase, pyruvate kinase enzyme activities. Moreover, lycopene can promote skeletal muscle triglyceride deposition, enhanced the mRNA expression of genes related to lipid synthesis, reduced the mRNA expression of genes related to lipolysis. And high-fat diet-induced dyslipidemia and oxidative stress were attenuated after lycopene supplementation. Additionally, lycopene supplementation reduced the glycolytic reserve but enhanced mitochondrial ATP production in C2C12 cells. These results demonstrated that lycopene affects the activities of metabolic enzymes in muscle fibers, promotes the expression of slow-twitch fibers, and enhanced mitochondrial respiratory capacity. We speculated that lycopene affects the muscle-fiber type through aerobic oxidation, suggesting that lycopene exerts potential beneficial effects on skeletal muscle metabolism.

Notoginsenoside R1 protects boar sperm during liquid storage at 17°C.

Reactive oxygen species (ROS) damage mammalian sperm during liquid storage. Notoginsenoside R1 (NR1) is a compound isolated from the roots of Panax notoginseng; it has powerful ROS-scavenging activities. This work hypothesized that the antioxidant capacity of NR1 could improve boar sperm quality and fertility during liquid storage. During liquid storage at 17°C, the supplementation of semen extender with NR1 (50 µM) significantly improved sperm motility, membrane integrity and acrosome integrity after 5 days of preservation. NR1 treatment also reduced ROS and lipid peroxidation (LPO) levels at day 5 (p <0.05). Higher glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) levels and sperm-zona pellucida binding capacity were observed in the 50 µM NR1 group than those in the control group at day 7 (p <0.05). Importantly, statistical analysis of the fertility of 200 sows indicated that addition of NR1 to the extender improved the fertility parameters of boar spermatozoa during liquid storage at 17°C (p <0.05). These results demonstrate the practical feasibility of using 50 µM NR1 as an antioxidant in boar extender during liquid storage at 17°C, which is beneficial to both spermatozoa quality and fertility.

Genome-Wide Differential Expression Profiling of Ovarian circRNAs Associated With Litter Size in Pigs.

Circular RNAs (circRNAs) have been emerging as an important regulator in mammalian reproduction via acting as miRNA sponges. However, the circRNAs in porcine ovaries related with litter size remains largely unknown. In this study, porcine ovaries with smaller or larger litter size (LLS) were subjected to high-throughput RNA sequencing. In total, 38,722 circRNAs were identified, of which 1,291 circRNAs were commonly expressed in all samples. There were 56 circRNAs significantly down-regulated and 54 circRNAs up-regulated in LLS pig (|log2 (fold change) | > 1, FDR < 0.05). Bioinformatics predicted that most of circRNAs harbored miRNA binding sites, and the expression patterns of circRNAs and their putative binding miRNAs were validated by qPCR. Moreover, the expression of circ-TCP11/miR-183 was significantly reversely correlated and their direct interaction was confirmed by dual-luciferase assay. Our study indicates that circRNAs may play potential effects on modulating porcine litter size.

GosB Inhibits Triacylglycerol Synthesis and Promotes Cell Survival in Mouse Mammary Epithelial Cells.

It has been demonstrated that the activator protein related transcription factor Finkel-Biskis-Jinkins murine osteosarcoma B (GosB) is involved in preadipocyte differentiation and triacylglycerol synthesis. However, the role of GosB in regulating the synthesis of milk fatty acid in mouse mammary glands remains unclear. This research uncovered potentially new roles of GosB in suppressing milk fatty acid synthesis. Results revealed that GosB had the highest expression in lung tissue and showed a higher expression level during nonlactation than during lactation. GosB inhibited the expression of fatty acid synthase (FASN), stearoyl-CoA desaturase (SCD), fatty acid binding protein 4 (FABP4), diacylglycerol acyltransferase 1 (DGAT1), perilipin 2 (PLIN2), perilipin 3 (PLIN3), and C/EBPα in mouse mammary gland epithelial cells (MEC). In addition, GosB reduced cellular triglyceride content and the accumulation of lipid droplets; in particular, GosB enhanced saturated fatty acid concentration (C16:0 and C18:0). The PPARγ agonist, rosiglitazone (ROSI), promoted apoptosis and inhibited cell proliferation. GosB increased the expression of Bcl-2 and protected MEC from ROSI-induced apoptosis. Furthermore, MECs were protected from apoptosis through the GosB regulation of intracellular calcium concentrations. These findings suggest that GosB may regulate mammary epithelial cells milk fat synthesis and apoptosis via PPARγ in mouse mammary glands.

Cellular microRNA miR-10a-5p inhibits replication of porcine reproductive and respiratory syndrome virus by targeting the host factor signal recognition particle 14.

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important viruses affecting the swine industry worldwide. MicroRNAs have recently been demonstrated to play vital roles in virus-host interactions. Our previous research on small RNA deep sequencing showed that the expression level of miR-10a increased during the viral life cycle. The present study sought to determine the function of miR-10a and its molecular mechanism during PRRSV infection. In the current study, the result of PRRSV infection inducing miR-10a expression was validated by quantitative reverse transcriptase PCR. Overexpression of miR-10a-5p using its mimics markedly reduced the expression level of intracellular PRRSV ORF7 mRNA and N protein. Simultaneously, overexpression of miR-10a-5p also significantly decreased the expression level of extracellular viral RNA and virus titres in the supernatants. These results demonstrated that miR-10a-5p could suppress the replication of PRRSV. A direct interaction between miR-10a-5p and signal recognition particle 14 (SRP14) was confirmed using bioinformatic prediction and experimental verification. miR-10a-5p could directly target the 3'UTR of pig SRP14 mRNA in a sequence-specific manner and decrease SRP14 expression through translational repression but not mRNA degradation. Further, knockdown of SRP14 by small interfering RNA also inhibits the replication of PRRSV. Collectively, these results suggested that miR-10a-5p inhibits PRRSV replication through suppression of SRP14 expression, which not only provides new insights into virus-host interactions during PRRSV infection but also suggests potential new antiviral strategies against PRRSV infection.