Brain-restricted mTOR inhibition with binary pharmacology.

On-target-off-tissue drug engagement is an important source of adverse effects that constrains the therapeutic window of drug candidates1,2. In diseases of the central nervous system, drugs with brain-restricted pharmacology are highly desirable. Here we report a strategy to achieve inhibition of mammalian target of rapamycin (mTOR) while sparing mTOR activity elsewhere through the use of the brain-permeable mTOR inhibitor RapaLink-1 and the brain-impermeable FKBP12 ligand RapaBlock. We show that this drug combination mitigates the systemic effects of mTOR inhibitors but retains the efficacy of RapaLink-1 in glioblastoma xenografts. We further present a general method to design cell-permeable, FKBP12-dependent kinase inhibitors from known drug scaffolds. These inhibitors are sensitive to deactivation by RapaBlock, enabling the brain-restricted inhibition of their respective kinase targets.

Gut-Liver Axis as a Therapeutic Target for Drug-Induced Liver Injury.

Drug-induced liver injury (DILI) is a liver disease that remains difficult to predict and diagnose, and the underlying mechanisms are yet to be fully clarified. The gut-liver axis refers to the reciprocal interactions between the gut and the liver, and its homeostasis plays a prominent role in maintaining liver health. It has been recently reported that patients and animals with DILI have a disrupted gut-liver axis, involving altered gut microbiota composition, increased intestinal permeability and lipopolysaccharide translocation, decreased short-chain fatty acids production, and impaired bile acid metabolism homeostasis. The present review will summarize the evidence from both clinical and preclinical studies about the role of the gut-liver axis in the pathogenesis of DILI. Moreover, we will focus attention on the potential therapeutic strategies for DILI based on improving gut-liver axis function, including herbs and phytochemicals, probiotics, fecal microbial transplantation, postbiotics, bile acids, and Farnesoid X receptor agonists.

Effects of diets with various levels of forage rape (Brassica napus) on growth performance, carcass traits, meat quality and rumen microbiota of Hu lambs.

BACKGROUND: Apart from being an oil crop, forage rape (Brassica napus) can be used to feed ruminants. The objective of this study was to investigate the effects of pelleted total mixed ration (TMR) diets with various levels of forage rape on growth performance, carcass traits, meat quality, meat nutritional value and rumen microbiota of Hu lambs, which was important for the efficient utilization of forage rape and alleviating the shortage of high-quality forage in China. RESULTS: Lambs fed on diets with 200-400 g kg-1 forage rape had greater average daily gain (ADG) and lower feed conversion ratio (FCR) than those fed on diets with 0-100 g kg-1 of forage rape (P < 0.05). As dietary forage rape levels increased, the content of intramuscular α-linolenic acid and a variety of amino acids in the muscle increased linearly (P < 0.05). No difference was found in carcass traits or meat quality among the dietary treatments (P > 0.05). However, the inclusion of forage rape increased the relative abundance of cellulolytic bacteria and short-chain fatty acid producers, including Succiniclasticum, Fibrobacter and members of the Lachnospiraceae. Besides, Succiniclasticum was found to be positively correlated with the final body weight of lambs. CONCLUSION: TMR diets that included 200-400 g kg-1 forage rape could improve the growth performance of lambs, and elevated the content of intramuscular α-linolenic acid and a variety of amino acids in the muscle, accompanied by increased abundance of cellulolytic bacteria in the rumen.

Expression and characterization of a novel trehalase from Microvirga sp. strain MC18.

Trehalase catalyzes the hydrolysis of trehalose into two glucose molecules and is present in nearly all tissues in various forms. In this study, a putative bacterial trehalase gene, encoding a glycoside hydrolase family 15 (GH15) protein was identified in Microvirga sp. strain MC18 and heterologously expressed in E. coli. The specific activity of the purified recombinant trehalase MtreH was 24 U/mg, with Km and Vmax values of 23.45 mg/mL and 184.23 µmol/mg/min, respectively. The enzyme exhibited optimal activity at 40 °C and pH 7.0, whereby Ca2+ had a considerable positive effects on the catalytic activity and thermostability. The optimized enzymatic reaction conditions for the bioconversion of trehalose using rMtreH were determined as 40 °C, pH 7.0, 10 h and 1% trehalose concentration. The characterization of this bacterial trehalase improves our understanding of the metabolism and biological role of trehalose in prokaryotic organism.

Expression and characterization of 1,4-α-glucan branching enzyme from Microvirga sp. MC18 and its application in the preparation of slowly digestible starch.

Nutraceuticals containing modified starch with increased content of slowly-digestible starch (SDS) may reduce the prevalence of obesity, diabetes and cardiovascular diseases due to its slow digestion rate. Enzymatic methods for the preparation of modified starch have attracted increasing attention because of their low environmental impact, safety and specificity. In this study, the efficient glucan branching enzyme McGBE from Microvirga sp. MC18 was identified, and its relevant properties as well as its potential for industrial starch modification were evaluated. The purified McGBE exhibited the highest specificity for potato starch, with a maximal specific activity of 791.21 U/mg. A time-dependent increase in the content of α-1,6 linkages from 3.0 to 6.0% was observed in McGBE-modified potato starch. The proportion of shorter chains (degree of polymerization, DP < 13) increased from 29.2 to 63.29% after McGBE treatment, accompanied by a reduction of the medium length chains (DP 13-24) from 52.30 to 35.99% and longer chains (DP > 25) from 18.51 to 0.72%. The reduction of the storage modulus (G') and retrogradation enthalpy (ΔHr) of potato starch with increasing treatment time demonstrated that McGBE could inhibit the short- and long-term retrogradation of starch. Under the optimal conditions, the SDS content of McGBE-modified potato starch increased by 65.8% compared to native potato starch. These results suggest that McGBE has great application potential for the preparation of modified starch with higher SDS content that is resistant to retrogradation.

Mechanisms of Selective Autophagy.

Autophagy is a lysosome-dependent degradation process. During autophagy, cytoplasmic components are sequestered and catabolized to supply nutrition and energy under starvation conditions. Recent work has demonstrated that many cargos can be specifically recognized and then eliminated via the core mechanism of autophagy which is termed as selective autophagy. The cargo recognition program provides the basis for the specific degradation of selective autophagy; thus, the exploration of the interaction between the cargo and the receptor is the key for revealing the underlying mechanism. Also, receptor protein complexes are required in various selective autophagy subtypes which process and guide the cargo to the core mechanism. Ubiquitination and phosphorylation are the main methods to modulate the affinity of the receptor toward cargo. Although many key processes of selective autophagy subtypes have been discovered and intensively studied, the precise ways in which the mechanisms of cargo recognition function remain mostly elusive. A fuller mechanistic understanding of selective autophagy will be important for efforts to promote disease treatment and drug development.

Effects of dietary ramie level on growth performance, serum biochemical indices, and meat quality of Boer goats.

This study was conducted to evaluate the use of ramie as forage on growth performance, serum biochemical indices, and meat quality of Boer goats. For this, 60 Boer lambs were divided into four groups fed the TMR with 0%, 10%, 20%, and 40% (control, and groups I, II, III, respectively) ramie. The experiment lasted for 90 days with a pretest for 15 days. Venous blood and longissimus dorsi (LD) muscle samples were collected after 24 h fasted at the end of the experiment. The results showed that ramie seems no significant changes in average daily gain (ADG) and other parameters for growth performance, only 40% ramie in TMR significantly reduced average daily feed intake (ADFI) (P < 0.05). Compared to the control, group II (20%) showed significant increases in total protein (TP) and globulin (GLB) levels, and decreases in albumin/globulin level (P < 0.05) in serum. Meanwhile, serum total cholesterol (TC) (P < 0.05) and free thyroxine (FT4) level were significantly reduced with up to 20% or more ramie in TMR. Moreover, the total amino acid and flavor amino acid levels in LD muscle were not affected by ramie. However, significant increases (P < 0.05) were observed in linoleic acid, polyunsaturated fatty acid, and polyunsaturated fatty acid/saturated fatty acid levels in group II. Overall, these results indicated that up to 20% ramie in TMR have no impairment in growth performance, health and meat quality, whereas high level ramie might have a negative effect on feed intake.

Pleiotropic role for MYCN in medulloblastoma.

Medulloblastoma (MB) is the most common malignant brain tumor of childhood. Sonic Hedgehog (SHH) signaling drives a minority of MB, correlating with desmoplastic pathology and favorable outcome. The majority, however, arises independently of SHH and displays classic or large cell anaplastic (LCA) pathology and poor prognosis. To identify common signaling abnormalities, we profiled mRNA, demonstrating misexpression of MYCN in the majority of human MB and negligible expression in normal cerebella. We clarified a role in pathogenesis by targeting MYCN (and luciferase) to cerebella of transgenic mice. MYCN-driven MB showed either classic or LCA pathologies, with Shh signaling activated in approximately 5% of tumors, demonstrating that MYCN can drive MB independently of Shh. MB arose at high penetrance, consistent with a role for MYCN in initiation. Tumor burden correlated with bioluminescence, with rare metastatic spread to the leptomeninges, suggesting roles for MYCN in both progression and metastasis. Transient pharmacological down-regulation of MYCN led to both clearance and senescence of tumor cells, and improved survival. Targeted expression of MYCN thus contributes to initiation, progression, and maintenance of MB, suggesting a central role for MYCN in pathogenesis.

Combined BRAFV600E and MEK blockade for BRAFV600E-mutant gliomas.

BRAFV600E is a common finding in glioma (about 10-60% depending on histopathologic subclassification). BRAFV600E monotherapy shows modest preclinical efficacy against BRAFV600E gliomas and also induces adverse secondary skin malignancies. Here, we examine the molecular mechanism of intrinsic resistance to BRAFV600E inhibition in glioma. Furthermore, we investigate BRAFV600E/MEK combination therapy that overcomes intrinsic resistance to BRAFV600E inhibitor and also prevents BRAFV600E inhibitor induced secondary malignancies. Immunoblotting and Human Phospho-Receptor Tyrosine Kinase Array assays were used to interrogate MAPK pathway activation. The cellular effect of BRAFV600E and MEK inhibition was determined by WST-1 viability assay and cell cycle analysis. Flanked and orthotopic GBM mouse models were used to investigate the in vivo efficacy of BRAFV600E/MEK combination therapy and the effect on secondary malignancies. BRAFV600E inhibition leads to recovery of ERK phosphorylation. Combined BRAFV600E and MEK inhibition prevents reactivation of the MAPK signaling, which correlates with decreased cell viability and augmented cell cycle arrest. Similarly, mice bearing BRAFV600E glioma showed reduced tumor growth when treated with a combination of BRAFV600E and MEK inhibitor compared to BRAFV600E inhibition alone. Additional benefit of BRAFV600E/MEK inhibition was reflected by reduced cutaneous squamous-cell carcinoma (cSCC) growth (a surrogate for RAS-driven secondary maligancies). In glioma, recovery of MAPK signaling upon BRAF inhibition accounts for intrinsic resistance to BRAFV600E inhibitor. Combined BRAFV600E and MEK inhibition prevents rebound of MAPK activation, resulting in enhanced antitumor efficacy and also reduces the risk of secondary malignancy development.

Dietary leucine supplementation alters energy metabolism and induces slow-to-fast transitions in longissimus dorsi muscle of weanling piglets.

Leucine plays an important role in promoting muscle protein synthesis and muscle remodelling. However, what percentage of leucine is appropriate in creep feed and what proteome profile alterations are caused by dietary leucine in the skeletal muscle of piglets remain elusive. In this case, we applied isobaric tags for relative and absolute quantitation to analyse the proteome profile of the longissimus dorsi muscles of weanling piglets fed a normal leucine diet (NL; 1·66 % leucine) and a high-leucine diet (HL; 2·1 % leucine). We identified 157 differentially expressed proteins between these two groups. Bioinformatics analysis of these proteins exhibited the suppression of oxidative phosphorylation and fatty acid ß-oxidation, as well as the activation of glycolysis, in the HL group. For further confirmation, we identified that SDHB, ATP5F1, ACADM and HADHB were significantly down-regulated (P<0·01, except ATP5F1, P<0·05), whereas the glycolytic enzyme pyruvate kinase was significantly up-regulated (P<0·05) in the HL group. We also show that enhanced muscle protein synthesis and the transition from slow-to-fast fibres are altered by leucine. Together, these results indicate that leucine may alter energy metabolism and promote slow-to-fast transitions in the skeletal muscle of weanling piglets.

Global Liver Proteome Analysis Using iTRAQ Reveals AMPK-mTOR-Autophagy Signaling Is Altered by Intrauterine Growth Restriction in Newborn Piglets.

Intrauterine growth restriction (IUGR) impairs fetal growth and development, perturbs nutrient metabolism, and increases the risk of developing diseases in postnatal life. However, the underlying mechanisms by which IUGR affects fetal liver development and metabolism remain incompletely understood. Here, we applied a high-throughput proteomics approach and biochemical analysis to investigate the impact of IUGR on the liver of newborn piglets. As a result, we identified 78 differentially expressed proteins in the three biological replicates, including 31 significantly up-regulated proteins and 47 significantly down-regulated proteins. Among them, a majority of differentially expressed proteins were related to nutrient metabolism and mitochondrial function. Additionally, many significantly down-regulated proteins participated in the mTOR signaling pathway and the phagosome maturation signaling pathway. Further analysis suggested that glucose concentration and hepatic glycogen storage were both reduced in IUGR newborn piglets, which may contribute to AMPK activation and mTORC1 inhibition. However, AMPK activation and mTORC1 inhibition failed to induce autophagy in the liver of IUGR neonatal pigs. A possible reason is that PP2Ac, a potential candidate in autophagy regulation, is significantly down-regulated in the liver of IUGR newborn piglets. These findings may provide implications for preventing and treating IUGR in human beings and domestic animals.

Quantitative proteomics analysis reveals glutamine deprivation activates fatty acid ß-oxidation pathway in HepG2 cells.

Glutamine, a multifunctional amino acid, functions in nutrient metabolism, energy balance, apoptosis, and cell proliferation. Lipid is an important nutrient and controls a broad range of physiological processes. Previous studies have demonstrated that glutamine can affect lipolysis and lipogenesis, but the effect of glutamine on the detailed lipid metabolism remains incompletely understood. Here, we applied the quantitative proteomics approach to estimate the relative abundance of proteins in HepG2 cells treated by glutamine deprivation. The results showed that there were 212 differentially abundant proteins in response to glutamine deprivation, including 150 significantly increased proteins and 62 significantly decreased proteins. Interestingly, functional classification showed that 43 differentially abundant proteins were related to lipid metabolism. Further bioinformatics analysis and western blotting validation revealed that lipid accumulation may be affected by ß-oxidation of fatty acid induced by glutamine deprivation in HepG2 cells. Together, our results may provide the potential for regulating lipid metabolism by glutamine in animal production and human nutrition. The MS data have been deposited to the ProteomeXchange Consortium with identifier PXD003387.

Dual blockade of lipid and cyclin-dependent kinases induces synthetic lethality in malignant glioma.

Malignant glioma, the most common primary brain tumor, is generally incurable. Although phosphatidylinositol-3-kinase (PI3K) signaling features prominently in glioma, inhibitors generally block proliferation rather than induce apoptosis. Starting with an inhibitor of both lipid and protein kinases that induced prominent apoptosis and that failed early clinical development because of its broad target profile and overall toxicity, we identified protein kinase targets, the blockade of which showed selective synthetic lethality when combined with PI3K inhibitors. Prioritizing protein kinase targets for which there are clinical inhibitors, we demonstrate that cyclin-dependent kinase (CDK)1/2 inhibitors, siRNAs against CDK1/2, and the clinical CDK1/2 inhibitor roscovitine all cooperated with the PI3K inhibitor PIK-90, blocking the antiapoptotic protein Survivin and driving cell death. In addition, overexpression of CDKs partially blocked some of the apoptosis caused by PIK-75. Roscovitine and PIK-90, in combination, were well tolerated in vivo and acted in a synthetic-lethal manner to induce apoptosis in human glioblastoma xenografts. We also tested clinical Akt and CDK inhibitors, demonstrating induction of apoptosis in vitro and providing a preclinical rationale to test this combination therapy in patients.

A dual PI3 kinase/mTOR inhibitor reveals emergent efficacy in glioma.

The PI3 kinase family of lipid kinases promotes cell growth and survival by generating the second messenger phosphatidylinositol-3,4,5-trisphosphate. To define targets critical for cancers driven by activation of PI3 kinase, we screened a panel of potent and structurally diverse drug-like molecules that target this enzyme family. Surprisingly, a single agent (PI-103) effected proliferative arrest in glioma cells, despite the ability of many compounds to block PI3 kinase signaling through its downstream effector, Akt. The unique cellular activity of PI-103 was traced directly to its ability to inhibit both PI3 kinase alpha and mTOR. PI-103 showed significant activity in xenografted tumors with no observable toxicity. These data demonstrate an emergent efficacy due to combinatorial inhibition of mTOR and PI3 kinase alpha in malignant glioma.

Cervical cancer biomarker screening based on Raman spectroscopy and multivariate statistical analysis.

Cervical cancer (CC) stands as one of the most prevalent malignancies among females, and the examination of serum tumor markers(TMs) assumes paramount significance in both its diagnosis and treatment. This research delves into the potential of combining Surface-Enhanced Raman Spectroscopy (SERS) with Multivariate Statistical Analysis (MSA) to diagnose cervical cancer, coupled with the identification of prospective serum biomarkers. Serum samples were collected from 95 CC patients and 81 healthy subjects, with subsequent MSA employed to analyze the spectral data. The outcomes underscore the superior efficacy of Partial Least Squares Discriminant Analysis (PLS-DA) within the MSA framework, achieving predictive accuracy of 97.73 %, and exhibiting sensitivities and specificities of 100 % and 95.83 % respectively. Additionally, the PLS-DA model yields a Variable Importance in Projection (VIP) list, which, when coupled with the biochemical information of characteristic peaks, can be utilized for the screening of biomarkers. Here, the Random Forest (RF) model is introduced to aid in biomarker screening. The two findings demonstrate that the principal contributing features distinguishing cervical cancer Raman spectra from those of healthy individuals are located at 482, 623, 722, 956, 1093, and 1656 cm-1, primarily linked to serum components such as DNA, tyrosine, adenine, valine, D-mannose, and amide I. Predictive models are constructed for individual biomolecules, generating ROC curves. Remarkably, D-mannose of V (C-N) exhibited the highest performance, boasting an AUC value of 0.979. This suggests its potential as a serum biomarker for distinguishing cervical cancer from healthy subjects.

Dietary honokiol supplementation improves antioxidant capacity, enhances intestinal health, and modulates cecal microbial composition and function of broiler chickens.

Honokiol is a multifunctional polyphenol present in Magnolia officinalis. The effects of honokiol as a supplement in broiler chicken diets, and the underlying mechanisms, remain unclear. Therefore, the aim of the present study was to investigate the effects of honokiol on the growth performance, antioxidant capacity, and intestinal histomorphology of broiler chickens and to explore the underlying mechanisms. In total, 240 one-day-old broilers were randomly allocated to 5 dietary treatments, with 6 replicate pens and 8 birds per pen. Birds were fed a basal diet supplemented with 0 (blank control, BC), 100, 200, or 400 mg/kg honokiol (H100, H200, and H400), or 200 mg/kg bacitracin zinc (PC) for 42 d. The results showed that H200 and H400 increased body weight gain (BWG) and decreased feed conversion ratio (FCR) during the starter period (P < 0.05). H100 and H200 increased total superoxide dismutase (T-SOD) activity in the serum and decreased malondialdehyde (MDA) amount in the jejunum on d 42 (P < 0.05). Moreover, H100 increased villus height-to-crypt depth ratio in both the jejunum and ileum on d 21 (P < 0.05). PCR analysis showed that honokiol upregulated intestinal expression of glutathione peroxidase (GSH-Px) and downregulated intestinal expression of inducible nitric oxide synthase (iNOS) on d 42 (P < 0.05). The Shannon index, which represents the microbial alpha diversity, was reduced for the PC, H200, and H400 groups. Notably, honokiol treatment altered the cecal microbial community structure and promoted the enrichment of several bacteria, including Firmicutes and Lactobacillus. Higher production of short-chain fatty acids was observed in the cecal digesta of H100 birds, accompanied by an enriched glycolysis/gluconeogenesis pathway, according to the functional prediction of the cecal microbiota. This study provides evidence that honokiol improves growth performance, antioxidant capacity, and intestinal health of broiler chickens, possibly by manipulating the composition and function of the microbial community.

Dietary Morus alba L. leaf supplementation improves hepatic lipid accumulation of laying hens via downregulating CircACACA.

Fatty liver hemorrhagic syndrome (FLHS) is the most common metabolic disease in laying hens. Morus alba L. (mulberry) leaf has the effect of regulating lipid metabolism. We evaluated the effects of dietary 3% mulberry leaf (MUL) supplementation in production performance, egg quality, and liver lipid deposition in laying hens. Differentially expressed genes and circRNAs in the liver were identified using whole-transcriptome sequencing. We also evaluated the effects of the MUL extract using an in vitro model of primary hepatocytes induced by free fatty acids and explored the role of key circRNAs in this process. Dietary supplementation with 3% MUL alleviated liver steatosis in laying hens, as shown by decreased fatty liver color score, relative liver weight (P < 0.01), and triglyceride levels (P < 0.05), and showed a tendency to reduce the mortality rate of laying hens (P = 0.09). In addition, mulberry leaf supplementation significantly reduced cholesterol content in egg yolk (P < 0.01). Dietary mulberry leaf supplementation downregulated the expression of genes involved in fatty acid and cholesterol biosynthesis, and upregulated the expression of fatty acid oxidation-related genes in the liver. CircACACA, which is derived from exons 2 and 3 of the acetyl-CoA carboxylase alpha (ACACA) pre-mRNA, was significantly reduced in the MUL group (P < 0.01). Upregulation of circACACA expression reversed the lipid-lowering effect of mulberry leaf extract by upregulating sterol regulatory element-binding proteins 1 c (SREBP-1c) and fatty acid synthase (FASN) (P < 0.05). Overall, mulberry leaf is an effective therapeutic strategy for FLHS in hens and can improve liver lipid metabolism by downregulating circACACA.

Maternal Magnolol Supplementation during Pregnancy and Lactation Promotes Antioxidant Capacity, Improves Gut Health, and Alters Gut Microbiota and Metabolites of Weanling Piglets.

Maternal nutrition exerts a profound effect on the postnatal performance of offspring, especially during the weaning period. The multifunctional bioactive component magnolol (MAG) has shown promise as a dietary supplement. This study aimed to explore the effects of maternal MAG supplementation on the antioxidant capacity, gut health, gut microbiome, and metabolome composition of weanling piglets. Fifty pregnant sows were randomly divided into two equally sized groups, the control group and the group supplemented with 100 g/t MAG during the gestation and lactation periods, and 7 days postweaning, the pups were euthanized. The microbiome and metabolome features of weanling piglet colons were compared. Our results revealed that maternal MAG supplementation modified the serum redox status of weanling piglets by decreasing malondialdehyde concentration and increasing superoxide dismutase activity and total antioxidant capacity. Moreover, the decreased indicators of diarrhea were accompanied by improved gut barrier function, in which serum diamine oxidase concentration was decreased, and expressions of zona occludens-1, claudin-1, and intestinal alkaline phosphatase were increased in the colon of weanling piglets from sows supplemented with MAG. Further analysis of the gut microbiota indicated that maternal MAG supplementation significantly increased the relative abundance of beneficial bacteria in the colon of weanling piglets, including Faecalibacterium prausnitzii and Oscillospira. Metabolome analysis identified 540 differential metabolites in the colon of piglets from MAG-fed dams, of which glycerophospholipid classes were highly correlated with progeny gut health and key beneficial bacteria. Our findings indicated that maternal MAG supplementation can improve the oxidative status and gut health of weanling piglets, possibly due to alterations in the gut microbiota and metabolites.

Effects of magnolol and honokiol blend on performance, egg quality, hepatic lipid metabolism, and intestinal morphology of hens at late laying cycle.

Magnolol and its isomer honokiol are polyphenols with anti-oxidative and anti-inflammatory activities. We evaluated the effects of magnolol and honokiol supplementation alone or in combination with hen diets during the late laying cycle. A total of 540 Jingfen pink-shell laying hens (50 weeks old) were randomly assigned to six treatments: a control diet and diets supplemented with 300 mg/kg magnolol (M300), honokiol (H300), or 300 mg/kg total phenols with a magnolol/honokiol ratio of 2:1 (M200H100), 1:2 (M100H200), and 1:1 (M150H150). Compared with that of the control, all supplementation groups had higher laying rates and the M300, M100H200, and M150H150 groups showed comparatively lower feed conversion ratios. Magnolol and honokiol supplementation increased the Haugh units of fresh eggs at week 62 and alleviated the decline of the Haugh units of eggs stored for 14 days. Compared with that of the control group, the serum total antioxidant capacity of the M100H200 and M150H150 groups significantly increased, and all supplementation groups had higher total antioxidant capacity and lower malondialdehyde content in the liver. With respect to lipid metabolism, the M200H100 and M150H150 groups had lower total and relative liver weights compared with those of the control and H300 groups. The mRNA expression levels of CCAAT enhancer binding protein alpha, sterol regulatory element binding protein-1, fatty acid synthase and stearyl coenzyme A desaturase 1 involved in lipogenesis; microsomal triglyceride transfer protein and apolipoprotein B involved in fatty acid transport; and the proinflammatory cytokine interleukin-1 beta were lower in all supplementation groups compared with those in the control. With respect to gut health, the heights of the jejunum and ileum villi significantly increased in all supplementation groups compared with those of the control, and the jejunum villus heights of the M300 and M150H150 groups were higher than those of the H300 and M100H200 groups. The H300 and M150H150 groups had higher mRNA expression levels of zonula occludens-1 in the ileum compared with those in the control and M300 groups, whereas all supplementation groups had higher mRNA levels of claudin-1 than that of the control group. In conclusion, magnolol and honokiol improved hen performance and the albumen quality of fresh and stored eggs by improving the antioxidant capacity, liver lipid metabolism, and intestinal health of laying hens. The combination of magnolol and honokiol at a 1:1 ratio may be an optimal choice for hen diet supplementation.

Effects of Chitosan Oligosaccharide on Production Performance, Egg Quality and Ovarian Function in Laying Hens with Fatty Liver Syndrome.

This study aimed to investigate the role of chitosan oligosaccharide (COS) as an additive in the feed of laying hens with fatty liver syndrome (FLS). Effects on production performance, egg quality as well as ovarian function were determined. A total of 360 Lohmann Pink-shell laying hens (28 weeks old) were randomly assigned to 5 groups (6 replicates × 12 birds). Hens were fed with a basal diet and a high-energy low-protein (HELP) diet supplemented with 0, 200, 400 and 800 mg/kg COS. COS reversed the lowered laying rates, increased feed-to-egg ratios and decreased albumen heights and Haugh units induced by the HELP diet. Additionally, COS improved the ovarian morphologies damaged by the HELP diet. Furthermore, COS enhanced antioxidant enzyme activities, reduced malonaldehyde levels and downregulated the mRNA expressions of nuclear factor kappa B, pro-inflammation cytokine genes and pro-apoptosis-related genes, while it upregulated the mRNA expression of anti-apoptosis-related genes in the ovaries of HELP-diet-fed hens. These findings suggested that dietary COS supplementation could improve production performance and egg quality in laying hens with FLS, and these beneficial effects were linked to improved ovarian morphology, which was attributed to decreased oxidative stress, inflammation and apoptosis in the ovaries.