Postnatal feeding with high-fat combined with high-glucose diet induces precocious puberty in Sprague‒Dawley rat pups.

With economic development and overnutrition, including high-fat diets (HFD) and high-glucose diets (HGD), the incidence of obesity in children is increasing, and thus, the incidence of precocious puberty is increasing. Therefore, it is of great importance to construct a suitable animal model of overnutrition-induced precocious puberty for further in-depth study. Here, we fed a HFD, HGD, or HFD combined with a HGD to pups after P-21 weaning, while weaned pups fed a normal diet served as the control group. The results showed that HFD combined with a HGD increased the body weight (BW) of weaned rat pups. In addition, a HFD, HGD, and HFD combined with a HGD lowered the age at which vaginal opening occurred and accelerated the vaginal cell cycle. Furthermore, a HFD combined with a HGD increased the weight of the uterus and ovaries of weaned rat pups. Additionally, a HFD combined with a HGD promoted the development of reproductive organs in weaned female rat pups. Ultimately, a HFD combined with a HGD was found to elevate the serum levels of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle stimulating hormone (FSH), leptin, adiponectin, and oestradiol (E2) and increase hypothalamic GnRH, Kiss-1, and GPR54 expression levels in weaned female rat pups. The current study found that overnutrition, such as that through a HFD combined with HGD, could induce precocious puberty in weaned female rat pups. In addition, a rat model of overnutrition-induced precocious puberty was established.

SP2-induced circPUM1 modulates chemoresistance and nature killer cell toxicity in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is a type of tumour found in the cavity that is characterized by differentiation and metastasis to the lymph nodes. Although diagnosis strategy and clinical treatment have recently improved, the outcomes for OSCC patients remain unsatisfactory. This study verified the characteristics of circPUM1 in OSCC cells, subsequently generating dysregulated circPUM1 cell models, showing that circPUM1 promoted chemoresistance and natural killer (NK) cell toxicity. Furthermore, the transcription factor SP2 regulated the expression of circPUM1 in OSCC cells, circPUM1 acted as a molecular sponge for miR-770-5p. Moreover, Nucleosome Assembly Protein 1 Like 1 (NAP1L1) is a downstream target for miR-770-5p and essential for circPUM1-mediated cisplatin resistance and NK cell cytotoxicity in OSCC cells. The network composed of SP2, circPUM1, miR-770-5p and NAP1L1 in OSCC appears to be a promising avenue for the development of novel targets for diagnosing or treating OSCC.

Gut microbiome combined with metabolomics reveals biomarkers and pathways in central precocious puberty.

BACKGROUND: Central precocious puberty (CPP) is a common disease in prepubertal children and results mainly from disorders in the endocrine system. Emerging evidence has highlighted the involvement of gut microbes in hormone secretion, but their roles and downstream metabolic pathways in CPP remain unknown. METHODS: To explore the gut microbes and metabolism alterations in CPP, we performed the 16S rRNA sequencing and untargeted metabolomics profiling for 91 CPP patients and 59 healthy controls. Bioinformatics and statistical analyses, including the comparisons of alpha and beta diversity, abundances of microbes, were undertaken on the 16S rRNA gene sequences and metabolism profiling. Classifiers were constructed based on the microorganisms and metabolites. Functional and pathway enrichment analyses were performed for identification of the altered microorganisms and metabolites in CPP. RESULTS: We integrated a multi-omics approach to investigate the alterations and functional characteristics of gut microbes and metabolites in CPP patients. The fecal microbiome profiles and fecal and blood metabolite profiles for 91 CPP patients and 59 healthy controls were generated and compared. We identified the altered microorganisms and metabolites during the development of CPP and constructed a machine learning-based classifier for distinguishing CPP. The Area Under Curves (AUCs) of the classifies were ranged from 0.832 to 1.00. In addition, functional analysis of the gut microbiota revealed that the nitric oxide synthesis was closely associated with the progression of CPP. Finally, we investigated the metabolic potential of gut microbes and discovered the genus Streptococcus could be a candidate molecular marker for CPP treatment. CONCLUSIONS: Overall, we utilized multi-omics data from microorganisms and metabolites to build a classifier for discriminating CPP patients from the common populations and recognized potential therapeutic molecular markers for CPP through comprehensive analyses.

Folic acid supplementation during pregnancy modulates hepatic methyl metabolism and genes expression profile of neonatal lambs of different litter sizes.

Maternal folic acid (FA) plays an important role in the fetus development, but it is unknown the response of hepatic metabolism in the offspring from different litter sizes to maternal FA supplementation. In the present study, this was done by feeding the ewes with 0, 16 and 32 mg/(kg·DM) FA supplemented diet during pregnancy and analysing the hepatic one-carbon metabolism-related indices and gene expression in the neonatal lambs of different litter sizes (twins, TW; triplets, TR). Regardless of litter sizes, the concentrations of folate, methionine, S-adenosylmethionine and DNA methyltransferase increased significantly, but homocysteine and S-adenosylhomocysteine decreased in the liver of newborn lambs from ewes whose diet was supplemented with FA. In TW, maternal FA status has little effect on hepatic genes expression profile of newborn lambs, and no significant enriched pathway was found. However, DEG involved in cell proliferation such as CCNA2, CCNB2, CCNE2, CDK1 and BUB1 were significantly enriched when the ewes were supplemented with FA in TR groups. In addition, nucleotide synthesis-related genes such as POLD1, POLD2, MCM4 and MCM5 were enriched markedly in DNA replication and pyrimidine metabolism pathways in triplets when a higher FA ingestion [32 mg/(kg·DM)] was implemented in ewes. This finding demonstrated that the hepatic methyl metabolism in TW and TR newborn lambs was regulated by maternal FA status. The hepatic cell proliferation and nucleotide metabolism related genes in TR were more susceptible to maternal dietary FA supplementation during pregnancy.

Vitamin E promotes ovine Sertoli cell proliferation by regulation of genes associated with cell division and the cell cycle.

The effect of Vitamin E on the proliferation of ovine Sertoli cells was investigated. Sertoli cells were isolated and treated with various amounts of Vitamin E (0 µM, 400 µM, 800 µM, 1000 µM, 1200 µM, 1400 µM and 1600 µM) for 24 h. We found that at the concentration of 1200 µM, Vitamin E promoted Sertoli cell proliferation very effectively. It also increased the proportion of cells in the G1 phase while reduced that in the S and G2/M phases, suggesting that its effect on Sertoli cell proliferation is achieved by enhancing progression through the cell cycle. In addition, Vitamin E significantly up-regulated the transcript level of the PDPN, BMP6, AMPKα, GSK3ß, Myc, and CDK6 genes and down-regulated that of PPARγ, Cyclin B1 and CDK4 as determined by qRT-PCR. Western blot analysis revealed that the expression of BMP6 and PDPN was also upregulated at the protein level, in accordance with the results of the qRT-PCR. Taken together, Vitamin E promoted Sertoli cell proliferation by affecting the expression of genes that regulate cell division and the cell cycle; this indicates that it can have a positive effect on sheep reproductive performance.

circ_0001461 promotes oral squamous cell carcinoma progression through miR-145/TLR4/NF-κB axis.

Circular RNAs (circRNAs) have been widely reported to participate in progression of various cancers, including oral cancer. Previous study showed circ_0001461 was aberrantly expressed in oral squamous cell carcinoma (OSCC), while its role in tumorigenesis of OSCC remains largely unclear. In this study, we confirmed that circ_0001461 was highly expressed in OSCC cell lines and tumor tissues. Knocking down of circ_0001461 suppressed cell proliferation, migration and invasion in vitro, and repress xenograft tumor growth in vivo. Mechanistically, we found circ_0001461 regulates OSCC cell proliferation, migration and invasion through sponging miR-145. Furthermore, circ_0001461 promotes the resistance of TNF-α-induced apoptosis of OSCC cells by modulating miR-145/TLR4/NF-κB pathway. In general, our study demonstrated a novel regulatory mechanism that circ_0001461/miR-145/TLR4/NF-κB axis modulates oral squamous cell carcinoma progression.

Effects of mulberry leaf silage on antioxidant and immunomodulatory activity and rumen bacterial community of lambs.

BACKGROUND: Rumen is a natural fermentation system and the microorganisms inside can effectively utilize plant bioresource and interact with host metabolism. Here, analysis of rumen microbiome, together with animal performance and serum metabolism in a lamb model were performed to identify the potential use of mulberry leaf silage (MS) to replace alfalfa silage (AS) as a new functional feed resource and to mining the novel specific mulberry leaf associated rumen bacteria interact with host metabolism. RESULTS: The lambs fed with MS diet showed improved antioxidant capacity and immune function compared to those fed AS diet. The MS diet significantly altered rumen microbiota α- and ß-diversity and taxonomic composition. Microbial analysis revealed that Bifidobacterium, Lactobacillus and Schwartzia were enhanced, and Ruminococcaceae UCG-010 and Lachnospiraceae_XPB1014_group were down-regulated in the rumen of MS group. A strong association was also found between these rumen microbial taxa and host antioxidant and immunomodulatory capacity. CONCLUSION: These findings indicated that mulberry leaf silage can be a high-quality feed source or bioactive pharmaceutical that is responsible for ruminant's health benefits. The modified rumen microbial community by mulberry leaf silage were associated with the enhanced antioxidant capacity and immunomodulatory of lambs.

Vitamin E Can Ameliorate Oxidative Damage of Ovine Hepatocytes In Vitro by Regulating Genes Expression Associated with Apoptosis and Pyroptosis, but Not Ferroptosis.

(1) Background: the current research was conducted to investigate the potential non-antioxidant roles of vitamin E in the protection of hepatocysts from oxidative damage. (2) Methods: primary sheep hepatocytes were cultured and exposed to 200, 400, 600, or 800 µmol/L hydrogen peroxide, while their viability was assessed using a CCK-8 kit. Then, cells were treated with 400 µmol/L hydrogen peroxide following a pretreatment with 50, 100, 200, 400, and 800 µmol/L vitamin E and their intracellular ROS levels were determined by means of the DCF-DA assay. RNA-seq, verified by qRT-PCR, was conducted thereafter: non-treated control (C1); cells treated with 400 µmol/L hydrogen peroxide (C2); and C2 plus a pretreatment with 100 µmol/L vitamin E (T1). (3) Results: the 200-800 µmol/L hydrogen peroxide caused significant cell death, while 50, 100, and 200 µmol/L vitamin E pretreatment significantly improved the survival rate of hepatocytes. ROS content in the cells pretreated with vitamin E was significantly lower than that in the control group and hydrogen-peroxide-treated group, especially in those pretreated with 100 µmol/L vitamin E. The differentially expressed genes (DEGs) concerning cell death involved in apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2), pyroptosis (NLRP3, IL-1ß, and IRAK2), and ferroptosis (TFRC and PTGS2). The abundances of IL-1ß, IRAK2, NLRP3, CASP8, CASP8AP2, RIPK1, and TLR7 were significantly increased in the C1 group and decreased in T1 group, while TFRC and PTGS2 were increased in T1 group. (4) Conclusions: oxidative stress induced by hydrogen peroxide caused cellular damage and death in sheep hepatocytes. Pretreatment with vitamin E effectively reduced intracellular ROS levels and protected the hepatocytes from cell death by regulating gene expression associated with apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2) and pyroptosis (NLRP3, IL-1ß, and IRAK2), but not ferroptosis (TFRC and PTGS2).

Triplet Male Lambs Are More Susceptible than Twins to Dietary Soybean Oil-Induced Fatty Liver.

BACKGROUND: Litter size affects fetal development but its relation to diet-induced fatty liver later in life is unknown. OBJECTIVES: This aim of this study was to test the hypothesis that litter size influences postweaning fatty liver development in response to soybean oil-supplemented diet. METHODS: Weanling twin (TW) or triplet (TP) male lambs (n = 16) were fed a control diet or 2% soybean oil-supplemented diet (SO) for 90 d. Liver tissue morphology, biochemical parameters, and lipid metabolic enzymes were determined. Hepatic gene expression was analyzed by RNA sequencing (n = 3), followed by enrichment analysis according to Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes. Differentially expressed genes involved in lipid metabolism were further verified by quantitative reverse transcriptase-polymerase chain reaction (n = 4). All data were analyzed by a 2-factor ANOVA, apart from differentially expressed genes, which were identified by the Benjamini-Hochberg approach (q value ≤0.05). RESULTS: SO increased liver triglyceride (by 55%) and nonesterified fatty acid (by 54%) concentrations in TPs (P ≤ 0.05) but not in TWs (P > 0.05). SO also induced a 2.3- and 2.1-fold increase in the liver steatosis score of TPs and TWs, respectively (P ≤ 0.05). Moreover, SO reduced the activity of lipolytic enzymes including hepatic lipase and total lipase in TPs by 47% and 25%, respectively (P ≤ 0.05). In contrast, activities of lipogenic enzymes, including malic enzyme and acetyl coenzyme A carboxylase, were significantly higher in TPs (P ≤ 0.05). Moreover, TPs had higher expression of lipogenic genes, such as FASN (by 45%) and APOB (by 72%), and lower expression of lipolytic genes, such as PRKAA2 (by 28%) and CPT1A (by 43%), compared with TWs (P ≤ 0.05). CONCLUSIONS: TPs have a gene expression profile that is more susceptible to SO-induced fatty liver than that of TWs, which indicates that insufficient maternal nutrient supply at fetal and neonatal stages may increase the risk of nonalcoholic fatty liver disease.

Multifaceted toxin profile, an approach toward a better understanding of probiotic Bacillus cereus.

Strains of the Bacillus cereus group have been widely used as probiotics for human beings, food animals, plants, and environmental remediation. Paradoxically, B. cereus is responsible for both gastrointestinal and nongastrointestinal syndromes and represents an important opportunistic food-borne pathogen. Toxicity assessment is a fundamental issue to evaluate safety of probiotics. Here, we summarize the state of our current knowledge about the toxins of B. cereus sensu lato to be considered for safety assessment of probiotic candidates. Surfactin-like emetic toxin (cereulide) and various enterotoxins including nonhemolytic enterotoxin, hemolysin BL, and cytotoxin K are responsible for food poisoning outbreaks characterized by emesis and diarrhea. In addition, other factors, such as hemolysin II, Certhrax, immune inhibitor A1, and sphingomyelinase, contribute to toxicity and overall virulence of B. cereus.

Dietary lycopene powder improves meat oxidative stability in Hu lambs.

BACKGROUND: The aim of this study was to evaluate the effect of dietary lycopene powder on meat quality and the oxidative stability of lipid and protein of longissimus thoracis (LT) in lamb. A total of 30 male lambs were randomly sampled from three feeding groups (control without lycopene supplement, 200 and 400 mg kg-1 lycopene powder respectively) after 3 months of feeding. The muscle samples were taken after slaughter and stored at 4 °C for 7 days. RESULTS: Compared with the control, the results showed that supplementation with lycopene powder gave a higher a* value (redness), and increased the levels of vitamin A and vitamin E. Increasing dietary lycopene powder resulted in a lower degree of lipid and protein oxidation, as evidenced by lower contents of thiobarbituric acid-reactive substance and carbonyl compounds, and higher levels of sulfhydryl groups. CONCLUSION: Dietary lycopene powder is an effective antioxidant that blocks the oxidation of meat proteins and lipids, and has a positive effect on increasing lamb meat quality during storage. © 2018 Society of Chemical Industry.

The Protective Effect of Sheep Placental Extract on Concanavalin A-induced Liver Injury in Mice.

Though the biological effects of human placental extract have been widely studied, it has limited availability and its use poses ethical problems. Thus, domestic animal placental extracts are suggested as alternatives. In this study, the protective effect of sheep placental extract (SPE) on concanavalin A (Con A)-induced liver injury was investigated. BALB/c mice were randomly divided into six groups, including one normal group and five experimental groups, which received different oral doses of SPE (0, 5, 10 and 50 mg/kg) or a mixture of amino acids for 3 days before Con A injection. Compared with Con A-induced model group, the SPE administration significantly decreased serum aminotransaminase activity, alleviated pathological changes, recovered liver antioxidant capacity and prevented the increase of nitric oxide. Secretion of pro-inflammatory cytokines in serum decreased and mRNA expression of hepatic intercellular adhesion molecule-1, interferon-inducible chemokine 10 and inducible nitric oxide synthase were downregulated, while B-cell lymphoma-2 expression increased. The administration of amino acids mixture had no significant effect in most measurements compared with the model group, which indicated proteins and peptides, rather than individual amino acid, were largely responsible for the bioactivity of SPE. The results indicate SPE has potential therapeutic effects against immune-mediated hepatitis.

Screening of α-Tocopherol Transfer Protein Sensitive Genes in Human Hepatoma Cells (HepG2).

α-Tocopherol transfer protein (α-TTP) is a ~32 kDa protein expressed mainly in hepatocytes. The major function of the protein is to bind specifically to α-tocopherol and, together, the complex transfers from late lysosomes to the cell membrane. A previous study indicated that some factors might be required in the transferring process. However, there is little information available about the potential transferring factors. In addition, there remains much to learn about other physiological processes which α-TTP might participate in. Thus, in this study a human α-TTP eukaryotic expression vector was successfully constructed and expressed in human hepatoma cells (HepG2). The sensitive genes related to α-TTP were then screened by microarray technology. Results showed that expression of the vector in HepG2 cells led to the identification of 323 genes showing differential expression. The differentially expressed transcripts were divided into four main categories, including (1) cell inflammation; (2) cell cycle and cell apoptosis; (3) cell signaling and gene regulation; and (4) cellular movement. A few cellular movement related transcripts were selected and verified by quantitative real-time PCR. Expressions of some were significantly increased in α-TTP-expressed group, which indicated that these factors were likely to play a role in the transferring process.

Influence of Restricted Grazing Time Systems on Productive Performance and Fatty Acid Composition of Longissimus dorsi in Growing Lambs.

Fifty 3-month-old male Tan lambs (similar in body weight) were divided into 5 groups to investigate the effects of different restricted pasture grazing times and indoor supplementation on the productive performances and fatty acid composition of the intramuscular fat in growing lambs. The lambs grazed for different periods of time (12 h/d, 8 h/d, 4 h/d, 2 h/d, and 0 h) and received various amounts of supplementary feedings during the 120-day trial. Pasture dry matter intake (DMI), total DMI, average daily gains and the live body weights of the lambs were measured during the experiment. The animals were slaughtered at the end of the study, their carcass traits were measured, and their longissimus dorsi muscles were sampled to analyze the intramuscular fat (IMF) content and fatty acid profiles. The results indicated that the different durations of grazing and supplementary feedings affected the animal performances and the composition of fatty acids. Grazing for 8 h/d or 2 h/d with the corresponding supplementary concentrate resulted in lambs with higher body weights, carcass weights and IMF contents. Lambs with longer grazing times and less concentrate accumulated more healthy fatty acids such as conjugated linoleic acid and n-3 polyunsaturated fatty acid and had higher n-3/n-6 ratios. Overall, a grazing allowance of 8 h/d and the corresponding concentrate was recommended to maintain a high quantity and quality of lamb meat.

Effects of Dietary Lycopene Supplementation on Plasma Lipid Profile, Lipid Peroxidation and Antioxidant Defense System in Feedlot Bamei Lamb.

Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old) were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate) or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p<0.05, linearly), total triglycerides (TG, p<0.05) and low-density lipoprotein cholesterol (LDL-C, p<0.05), as well as atherogenic index (p<0.001), whereas no change was observed in high-density lipoprotein cholesterol (p>0.05). The levels of TG (p<0.001) and LDL-C (p<0.001) were decreased with the feeding time extension, and both showed a linear trend (p<0.01). Malondialdehyde level in plasma and liver decreased linearly with the increase of lycopene inclusion levels (p<0.01). Dietary lycopene intake linearly increased the plasma antioxidant vitamin E level (p<0.001), total antioxidant capacity (T-AOC, p<0.05), and activities of catalase (CAT, p<0.01), glutathione peroxidase (GSH-Px, p<0.05) and superoxide dismutase (SOD, p<0.05). The plasma T-AOC and activities of GSH-Px and SOD decreased with the extension of the feeding time. In liver, dietary lycopene inclusion showed similar antioxidant effects with respect to activities of CAT (p<0.05, linearly) and SOD (p<0.001, linearly). Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment stress and maintain normal physiological metabolism.

Regulation of metabolism by circadian rhythms: Support from time-restricted eating, intestinal microbiota & omics analysis.

Circadian oscillatory system plays a key role in coordinating the metabolism of most organisms. Perturbation of genetic effects and misalignment of circadian rhythms result in circadian dysfunction and signs of metabolic disorders. The eating-fasting cycle can act on the peripheral circadian clocks, bypassing the photoperiod. Therefore, time-restricted eating (TRE) can improve metabolic health by adjusting eating rhythms, a process achieved through reprogramming of circadian genomes and metabolic programs at different tissue levels or remodeling of the intestinal microbiota, with omics technology allowing visualization of the regulatory processes. Here, we review recent advances in circadian regulation of metabolism, focus on the potential application of TRE for rescuing circadian dysfunction and metabolic disorders with the contribution of intestinal microbiota in between, and summarize the significance of omics technology.

Fat deposition and partitioning for meat production in cattle and sheep.

In markets for beef and sheep meat, an appropriate level of intramuscular fat (IMF) is highly desirable for meat-eating quality, but strategies to improve it usually lead to an undesirable excess in carcase fat, presenting a major challenge to livestock producers. To solve this problem, we need to understand the partitioning of fat among the major fat depots: IMF, subcutaneous fat (SCF) and visceral fat (VF). In most genotypes of cattle and sheep, the rate of accretion is lower for IMF than for SCF and VF, so genetic selection for a high level of IMF, or the use of an increased dietary energy supply to promote IMF deposition, will increase overall fatness and feed costs. On the other hand, feeding postnatal calves with excessive concentrates promotes IMF deposition, so a nutritional strategy is feasible. With genetic strategies, several problems arise: 1) positive genetic correlations between IMF, SCF and VF differ among genotypes in both cattle and sheep; 2) genotypes appear to have specific, characteristic rates of accretion of IMF during periods of growth and fattening; 3) most breeds of cattle and sheep naturally produce meat with relatively low levels of IMF, but IMF does vary substantially among individuals and breeds so progress is possible through accurate measurement of IMF. Therefore, an essential prerequisite for selection will be knowledge of the genetic correlations and fat accretion rates for each genotype. Currently, selection for IMF is based on existing technology that directly measures IMF in the progeny or siblings, or estimates IMF in live animals. New technology is needed to permit the simultaneous measurement of SCF and IMF in the field, thus opening up the possibility of accurate selection, particularly for fat partitioning in live animals. Specifically, there would be great value in detecting individuals with an IMF advantage at an early age so the generation interval could be shortened and genetic gain accelerated. Genetic gain would also be greatly aided if we could select for genes that control adipogenesis and lipogenesis and are also differentially expressed in the various depots.

Exploring the metabolomic landscape: Perilla frutescens as a promising enhancer of production, flavor, and nutrition in Tan lamb meat.

Addressing health-related concerns linked to the metabolite profile of lamb meat has become paramount, in line with the growing demand for enhanced flavor and taste. We examined the impact of Perilla frutescens seeds on Tan lamb growth, carcass traits, and metabolite profiles. Three diets were employed: a low-concentrate group (LC), a high-concentrate group (HC), and a PFS group (the LC diet supplemented with 3% Perilla frutescens seeds) on a dry matter basis. Forty-five male Tan-lambs (approximately six months) with similar body weights (25.1 kg ± 1.12 SD) were randomly assigned to one of these three groups for 84-day feeding, including an initial 14-day adjustment phase. The supplementation of PFS resulted in increased average daily gain (P < 0.01) and improved carcass quality and meat color (P < 0.05). Additionally, it led to an enhancement in omega-3 polyunsaturated fatty acids (P < 0.05) and a reduction in the omega-6/omega-3 ratio (P < 0.05). Using gas chromatography-mass spectrometry, 369 volatile compounds were identified with enhanced levels of acetaldehyde and 1,2,4-trimethyl-benzene associated with PFS (P < 0.05). Among the 807 compounds identified by ultra-high performance liquid chromatography-mass spectrometry, there were 66 significantly differential compounds (P < 0.05), including 43 hydrophilic metabolites and 23 lipids. PFS supplementation led to significant alterations in 66 metabolites, with three metabolites including 2,5-diisopropyl-3-methylphenol, 3-hydroxydecanoic acid, and lysophosphatidylcholine (15:0) emerging as potential PFS-related biomarkers. The study indicates that PFS supplementation can enhance Tan-lamb growth, feed efficiency, and meat quality, potentially providing lamb meat with improved flavor and nutritional characteristics.

Rumen microbiome-driven insight into bile acid metabolism and host metabolic regulation.

Gut microbes play a crucial role in transforming primary bile acids (BAs) into secondary forms, which influence systemic metabolic processes. The rumen, a distinctive and critical microbial habitat in ruminants, boasts a diverse array of microbial species with multifaceted metabolic capabilities. There remains a gap in our understanding of BA metabolism within this ecosystem. Herein, through the analysis of 9371 metagenome-assembled genomes and 329 cultured organisms from the rumen, we identified two enzymes integral to BA metabolism: 3-dehydro-bile acid delta4,6-reductase (baiN) and the bile acid:Na + symporter family (BASS). Both in vitro and in vivo experiments were employed by introducing exogenous BAs. We revealed a transformation of BAs in rumen and found an enzyme cluster, including L-ribulose-5-phosphate 3-epimerase and dihydroorotate dehydrogenase. This cluster, distinct from the previously known BA-inducible operon responsible for 7α-dehydroxylation, suggests a previously unrecognized pathway potentially converting primary BAs into secondary BAs. Moreover, our in vivo experiments indicated that microbial BA administration in the rumen can modulate amino acid and lipid metabolism, with systemic impacts underscored by core secondary BAs and their metabolites. Our study provides insights into the rumen microbiome's role in BA metabolism, revealing a complex microbial pathway for BA biotransformation and its subsequent effect on host metabolic pathways, including those for glucose, amino acids, and lipids. This research not only advances our understanding of microbial BA metabolism but also underscores its wider implications for metabolic regulation, offering opportunities for improving animal and potentially human health.

Long-Term Benefits of Cenchrus fungigraminus Residual Roots Improved the Quality and Microbial Diversity of Rhizosphere Sandy Soil through Cellulose Degradation in the Ulan Buh Desert, Northwest China.

Long-term plant residue retention can effectively replenish soil quality and fertility. In this study, we collected rhizosphere soil from the residual roots of annual Cenchrus fungigraminus in the Ulan Buh Desert over the past 10 years. The area, depth, and length of these roots decreased over time. The cellulose content of the residual roots was significantly higher in the later 5 years (2018-2022) than the former 5 years (2013-2017), reaching its highest value in 2021. The lignin content of the residual roots did not differ across samples except in 2015 and reached its highest level in 2021. The total sugar of the residual roots in 2022 was 227.88 ± 30.69 mg·g-1, which was significantly higher than that in other years. Compared to the original sandy soil, the soil organic matter and soil microbial biomass carbon (SMBC) contents were 2.17-2.41 times and 31.52-35.58% higher in the later 3 years (2020-2022) and reached the highest values in 2020. The residual roots also significantly enhanced the soil carbon stocks from 2018-2022. Soil dehydrogenase, nitrogenase, and N-acetyl-ß-D-glucosidase (S-NAG) were significantly affected from 2019-2022. The rhizosphere soil community richness and diversity of the bacterial and fungal communities significantly decreased with the duration of the residual roots in the sandy soil, and there was a significant difference for 10 years. Streptomyces, Bacillus, and Sphigomonas were the representative bacteria in the residual root rhizosphere soil, while Agaricales and Panaeolus were the enriched fungal genera. The distance-based redundancy analysis and partial least square path model results showed that the duration of residual roots in the sandy soil, S-NAG, and SMBC were the primary environmental characteristics that shaped the microbial community. These insights provide new ideas on how to foster the exploration of the use of annual herbaceous plants for sandy soil improvement in the future.