Oxidative stress has been associated with a number of physiological problems in swine,including reduced production efficiency.Recently,although there has been increased research into regulatory mechanisms and antioxid...Oxidative stress has been associated with a number of physiological problems in swine,including reduced production efficiency.Recently,although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production,it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress factors.Here,we discuss the dose and dose intensity of the causes of oxidative stress involving physiological,environmental and dietary factors,recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.展开更多
Background:Previous studies had shown that short-term acute heat stress(HS)affected the host’s metabolism and intestinal microbiota independent of feed intake(FI)reduction,and long-term calorie restriction caused int...Background:Previous studies had shown that short-term acute heat stress(HS)affected the host’s metabolism and intestinal microbiota independent of feed intake(FI)reduction,and long-term calorie restriction caused intestinal morphological injuries and gut microbial alterations.However,research on the effects of constant chronic HS on intestinal microbial composition and the roles of FI reduction played in is limited.This study aimed to investigate the effects of 7-day constant chronic HS on the composition of intestinal microbes in growing-finishing pigs,and its relationship with pigs’performance,intestinal morphology,and ileal immune response.Twenty-four growingfinishing pigs(Duroc×Large White×Landrace,30±1 kg body weight)were randomly assigned to three treatments(n=8),1)thermal neutral(TN)conditions(25±1℃)with ad libitum FI,2)HS conditions(35±1℃)with ad libitum FI,3)pair-fed(PF)with HS under TN conditions to discriminate the confounding effects of dissimilar FI,and the FI was the previous day’s average FI of HS.The small intestinal segments(duodenum,jejunum,and ileum)and feces were collected on d 8.Results:Results indicated that HS drastically declined(P<0.05)average daily gain(ADG)and average daily feed intake(ADFI)(about 61%)in comparison with TN,and caused hyperpyrexia,meanwhile PF caused hypothermia.Morphological observation by light and electron microscopes showed that both HS and PF treatment decreased(P<0.05)the villus and microvillus height compared with TN.Additionally,HS increased(P<0.05)protein expression of heat shock protein 70 in the duodenum,jejunum,and ileum.Furthermore,the expression of tight junction protein zonula occluden-1(ZO-1)in the duodenum and ileum,and Occludin in the ileum were enhanced(P<0.05)compared with TN and PF.Moreover,HS significantly enhanced(P<0.05)the mRNA relative expression of inflammatory cytokines(TLR-2,TLR-4,and tumor necrosis factor-α(TNF-α),IL-6,IL-8,PG1–5,β-defensin 2(pBD-2)),mucins(mucin-1 and mucin-2)and P65 protein level in the ileal mucosa tissue.Intestinal microbiota analysis by 16S rRNA sequencing showed lower(P<0.10)αdiversity in both HS and PF,and a separated cluster ofβdiversity among groups.Compared with TN,HS but not PF mainly reduced(FDR<0.05)Bacteroidetes(phylum),Bacteroidia(class)and elevated the proportions of Proteobacteria(phylum,FDR<0.05),Bacillales(order,FDR<0.05),Planococcaceae(family,FDR<0.05),Kurthia(genus,FDR<0.05),Streptococcaceae(family,FDR<0.10)and Streptococcus(genus,FDR<0.10).Notably,Lactobacillales(order)was decreased(FDR<0.05)by PF alone.Furthermore,the Spearman correlation analysis indicated that the microbes prevalent in HS were positively(P<0.05)associated with intestinal morphological injuries indicators and ileal immune response parameters,and the microbes reduced in HS were negatively(P<0.05)with the performance data.Conclusions:Intestinal morphological injuries and ileal immune response caused by constant chronic HS independent of FI showed close connections with alterations in intestinal microbiota in growing-finishing pigs.展开更多
Background:The objective of this experiment was to investigate the influence of dietary tributyrin on intestinal mucosa development,oxidative stress,mitochondrial function and AMPK-mTOR signaling pathway.Methods:Seven...Background:The objective of this experiment was to investigate the influence of dietary tributyrin on intestinal mucosa development,oxidative stress,mitochondrial function and AMPK-mTOR signaling pathway.Methods:Seventy-two pigs were divided into two treatments and received either a basal diet or the same diet supplemented with 750 mg/kg tributyrin.Each treatment has six replicates of six pigs.After 14 days,6 pigs from each treatment were selected and the jejunal samples were collected.Results:Results showed that supplemental tributyrin increased(P<0.05)villus height and villus height:crypt depth of weaned pigs.Pigs fed tributyrin had greater(P<0.05)RNA/DNA and protein/DNA ratios than pigs on the control group.The mRNA levels of sodium glucose transport protein-1 and glucose transporter-2 in the jejunum were upregulated(P<0.05)in pigs fed the tributyrin diet.Dietary tributyrin supplementation lowered(P<0.05)the malondialdehyde and hydrogen peroxide(H2O2)content in jejunum,enhanced(P<0.05)the mitochondrial function,as demonstrated by decreased(P<0.05)reactive oxygen species level and increased(P<0.05)mitochondrial membrane potential.Furthermore,tributyrin increased(P<0.05)mitochondrial DNA content and the mRNA abundance of genes related to mitochondrial functions,including peroxisomal proliferator-activated receptor-γcoactivator-1α,mitochondrial transcription factor A,nuclear respiratory factor-1 in the jejunum.Supplementation with tributyrin elevated(P<0.05)the phosphorylation level of AMPK and inhibited(P<0.05)the phosphorylation level of mTOR in jejunum compared with the control group.Conclusions:These findings suggest that dietary supplementation with tributyrin promotes intestinal mucosa growth,extenuates oxidative stress,improves mitochondrial function and modulates the AMPK-mTOR signal pathway of weaned pigs.展开更多
Background： A series of modified montmorillonites（Mt） including zinc-loaded Mt（Zn-Mt）, copper-loaded Mt（Cu-Mt）, copper/zinc-loaded Mt with different Cu/Zn ratio（Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3） were prepar...Background： A series of modified montmorillonites（Mt） including zinc-loaded Mt（Zn-Mt）, copper-loaded Mt（Cu-Mt）, copper/zinc-loaded Mt with different Cu/Zn ratio（Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3） were prepared by an ion-exchange reaction, and characterized using X-ray diffraction（XRD）, fourier transformed infrared spectroscopy（FTIR） and transmission electron microscopy（TEM）. The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results： In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria（Escherichia coli）, gram-positive bacteria（Staphylococcus aureus）, fungi（Candida albicans）.Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions： The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.展开更多
This study aimed to investigate whether fetal growth trajectories(FGTs)could predict early childhood development,indicate intrauterine metabolic changes,and explore potential optimal and suboptimal FGTs.FGTs were deve...This study aimed to investigate whether fetal growth trajectories(FGTs)could predict early childhood development,indicate intrauterine metabolic changes,and explore potential optimal and suboptimal FGTs.FGTs were developed by using an unsupervised machine-learning approach.Children’s neurodevelopment,anthropometry,and respiratory outcomes in thefirst 6 years of life were assessed at different ages.In a subgroup of participants,we conducted a metabolomics analysis of cord blood to reveal the metabolic features of FGTs.We identified 6 FGTs:early decelerating,early decelerating with late catch-up growth,early accelerating,early accelerating with late medium growth,late decelerating,and late accelerating.The early accelerating with late medium growth pattern might be the optimal FGT due to its associations with better psychomotor development,mental development,intelligence quotient,and lung function and a lower risk of behaviour and respiratory problems.Compared with the optimal FGT,early decelerating and late decelerating FGTs were associated with poor neurodevelopment and lung function,while early accelerating FGT was associated with more severe autistic symptoms,poor lung function,and increased risks of overweight/obesity.Metabolic alterations were enriched in amino acid metabolism for early decelerating and late decelerating FGTs,whereas altered metabolites were enriched in lipid metabolism for early accelerating FGT.Thesefindings suggest that FGTs are predictors of early life development and may indicate intrauterine adaptive metabolism.The discovery of optimal and suboptimal FGTs provides potential clues for the early identification and intervention of fetal origin dysplasia or disease,but further research on related mechanisms is still needed.展开更多
Spherical nucleic acids(SNAs)are a 3D spherical nanostructure composed of highly oriented,dense layers of oligonucleotides conjugated to a hollow or solid core.This structure allows SNAs to show resistance to nuclease...Spherical nucleic acids(SNAs)are a 3D spherical nanostructure composed of highly oriented,dense layers of oligonucleotides conjugated to a hollow or solid core.This structure allows SNAs to show resistance to nuclease degradation,enter into nearly all cells without transfection agents and enable precise interactions with target molecules.Based on superior biological properties,SNAs can be tailored for diverse biological applications,rendering them a flexible and biosafe tool for biological applications as well as an enabling platform for therapy.In this review,we mainly discuss the structure and conjugation mode of SNAs and focus on recent advances in their applications,such as biomedical detection,imaging,and drug delivery.Finally,the remaining challenges and future directions of SNAs are also discussed and proposed.展开更多
The effect of reactive element yttrium on purification and carbide precipitation of superalloy K4169 has been studied through vacuum induction melting.The results show that yttrium has a strong deoxidizing and desulfu...The effect of reactive element yttrium on purification and carbide precipitation of superalloy K4169 has been studied through vacuum induction melting.The results show that yttrium has a strong deoxidizing and desulfurizing ability,and the impurity elements of sulfur and oxygen in melting K4169 are greatly reduced to 2-5 ppm and 4-5 ppm,respectively.The metallurgical reaction product is mainly Y_(2)O_(3)and yttrium containing sulfides have not been observed.With the increase of the content of yttrium from0.005 wt.%to 0.033 wt.%,the morphology and size of MC carbides in casting are significantly influenced due to that the yttrium changes the diffusion of the carbide forming elements and solid fraction during solidification.In the alloys without yttrium,only isolated blocky or strip carbides exist,while skeletonlike carbides are observed in the alloys with yttrium.Both the average size and the number density of skeleton carbides decrease monotonously with yttrium content increasing.After yttrium increasing to 0.033 wt.%,a phase of hexagonal Ni17 Y2 is observed to precipitate in the form of symbiosis with MC carbide and matrix.The addition of yttrium is not beneficial for the properties of K4169 alloys at the room temperature,which is quite related to the MC carbides with a large skeleton-like morphology through the analysis of tensile fracture.展开更多
基金supported by Guangzhou Science and Technology Planning Project(2023A04J0131)Special fund for scientific innovation strategyconstruction of high level Academy of Agriculture Science(R2020PY-JG009,R2022PY-QY007,202106TD)+2 种基金China Agriculture Research System-CARS-35the Project of Swine Innovation Team in Guangdong Modern Agricultural Research System(2022KJ126)Special Fund for Rural Revitalization Strategy of Guangdong(2023TS-3),China。
文摘Oxidative stress has been associated with a number of physiological problems in swine,including reduced production efficiency.Recently,although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production,it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress factors.Here,we discuss the dose and dose intensity of the causes of oxidative stress involving physiological,environmental and dietary factors,recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.
基金supported by National Key Research and Development Program of China(2016YFD0500501)the China Agriculture Research System of MOF and MARA+1 种基金the Science and Technology Program of Guangdong Academy of Agricultural Sciences(R2020PY-JG009,202106TD)the Project of Swine Innovation Team in Guangdong Modern Agricultural Research System(2021KJ126)。
文摘Background:Previous studies had shown that short-term acute heat stress(HS)affected the host’s metabolism and intestinal microbiota independent of feed intake(FI)reduction,and long-term calorie restriction caused intestinal morphological injuries and gut microbial alterations.However,research on the effects of constant chronic HS on intestinal microbial composition and the roles of FI reduction played in is limited.This study aimed to investigate the effects of 7-day constant chronic HS on the composition of intestinal microbes in growing-finishing pigs,and its relationship with pigs’performance,intestinal morphology,and ileal immune response.Twenty-four growingfinishing pigs(Duroc×Large White×Landrace,30±1 kg body weight)were randomly assigned to three treatments(n=8),1)thermal neutral(TN)conditions(25±1℃)with ad libitum FI,2)HS conditions(35±1℃)with ad libitum FI,3)pair-fed(PF)with HS under TN conditions to discriminate the confounding effects of dissimilar FI,and the FI was the previous day’s average FI of HS.The small intestinal segments(duodenum,jejunum,and ileum)and feces were collected on d 8.Results:Results indicated that HS drastically declined(P<0.05)average daily gain(ADG)and average daily feed intake(ADFI)(about 61%)in comparison with TN,and caused hyperpyrexia,meanwhile PF caused hypothermia.Morphological observation by light and electron microscopes showed that both HS and PF treatment decreased(P<0.05)the villus and microvillus height compared with TN.Additionally,HS increased(P<0.05)protein expression of heat shock protein 70 in the duodenum,jejunum,and ileum.Furthermore,the expression of tight junction protein zonula occluden-1(ZO-1)in the duodenum and ileum,and Occludin in the ileum were enhanced(P<0.05)compared with TN and PF.Moreover,HS significantly enhanced(P<0.05)the mRNA relative expression of inflammatory cytokines(TLR-2,TLR-4,and tumor necrosis factor-α(TNF-α),IL-6,IL-8,PG1–5,β-defensin 2(pBD-2)),mucins(mucin-1 and mucin-2)and P65 protein level in the ileal mucosa tissue.Intestinal microbiota analysis by 16S rRNA sequencing showed lower(P<0.10)αdiversity in both HS and PF,and a separated cluster ofβdiversity among groups.Compared with TN,HS but not PF mainly reduced(FDR<0.05)Bacteroidetes(phylum),Bacteroidia(class)and elevated the proportions of Proteobacteria(phylum,FDR<0.05),Bacillales(order,FDR<0.05),Planococcaceae(family,FDR<0.05),Kurthia(genus,FDR<0.05),Streptococcaceae(family,FDR<0.10)and Streptococcus(genus,FDR<0.10).Notably,Lactobacillales(order)was decreased(FDR<0.05)by PF alone.Furthermore,the Spearman correlation analysis indicated that the microbes prevalent in HS were positively(P<0.05)associated with intestinal morphological injuries indicators and ileal immune response parameters,and the microbes reduced in HS were negatively(P<0.05)with the performance data.Conclusions:Intestinal morphological injuries and ileal immune response caused by constant chronic HS independent of FI showed close connections with alterations in intestinal microbiota in growing-finishing pigs.
基金National Natural Science Foundation of China(31872387)Zhejiang Provincial Natural Science Foundation(Sodium butyrate promotes restoration of intestinal barrier induced by oxidative stress in piglets through AMPK mediated mitophagy)and Zhejiang Provincal Key R&D Project(2019C02051).
文摘Background:The objective of this experiment was to investigate the influence of dietary tributyrin on intestinal mucosa development,oxidative stress,mitochondrial function and AMPK-mTOR signaling pathway.Methods:Seventy-two pigs were divided into two treatments and received either a basal diet or the same diet supplemented with 750 mg/kg tributyrin.Each treatment has six replicates of six pigs.After 14 days,6 pigs from each treatment were selected and the jejunal samples were collected.Results:Results showed that supplemental tributyrin increased(P<0.05)villus height and villus height:crypt depth of weaned pigs.Pigs fed tributyrin had greater(P<0.05)RNA/DNA and protein/DNA ratios than pigs on the control group.The mRNA levels of sodium glucose transport protein-1 and glucose transporter-2 in the jejunum were upregulated(P<0.05)in pigs fed the tributyrin diet.Dietary tributyrin supplementation lowered(P<0.05)the malondialdehyde and hydrogen peroxide(H2O2)content in jejunum,enhanced(P<0.05)the mitochondrial function,as demonstrated by decreased(P<0.05)reactive oxygen species level and increased(P<0.05)mitochondrial membrane potential.Furthermore,tributyrin increased(P<0.05)mitochondrial DNA content and the mRNA abundance of genes related to mitochondrial functions,including peroxisomal proliferator-activated receptor-γcoactivator-1α,mitochondrial transcription factor A,nuclear respiratory factor-1 in the jejunum.Supplementation with tributyrin elevated(P<0.05)the phosphorylation level of AMPK and inhibited(P<0.05)the phosphorylation level of mTOR in jejunum compared with the control group.Conclusions:These findings suggest that dietary supplementation with tributyrin promotes intestinal mucosa growth,extenuates oxidative stress,improves mitochondrial function and modulates the AMPK-mTOR signal pathway of weaned pigs.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201403047)Science Technology Department of Zhejiang Province(2015C02022)
文摘Background： A series of modified montmorillonites（Mt） including zinc-loaded Mt（Zn-Mt）, copper-loaded Mt（Cu-Mt）, copper/zinc-loaded Mt with different Cu/Zn ratio（Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3） were prepared by an ion-exchange reaction, and characterized using X-ray diffraction（XRD）, fourier transformed infrared spectroscopy（FTIR） and transmission electron microscopy（TEM）. The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results： In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria（Escherichia coli）, gram-positive bacteria（Staphylococcus aureus）, fungi（Candida albicans）.Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions： The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.
基金supported by the National Natural Science Foundation of China(U21A20397,22236001,42277428)the Program for HUST Academic Frontier Youth Team(2018QYTD12).
文摘This study aimed to investigate whether fetal growth trajectories(FGTs)could predict early childhood development,indicate intrauterine metabolic changes,and explore potential optimal and suboptimal FGTs.FGTs were developed by using an unsupervised machine-learning approach.Children’s neurodevelopment,anthropometry,and respiratory outcomes in thefirst 6 years of life were assessed at different ages.In a subgroup of participants,we conducted a metabolomics analysis of cord blood to reveal the metabolic features of FGTs.We identified 6 FGTs:early decelerating,early decelerating with late catch-up growth,early accelerating,early accelerating with late medium growth,late decelerating,and late accelerating.The early accelerating with late medium growth pattern might be the optimal FGT due to its associations with better psychomotor development,mental development,intelligence quotient,and lung function and a lower risk of behaviour and respiratory problems.Compared with the optimal FGT,early decelerating and late decelerating FGTs were associated with poor neurodevelopment and lung function,while early accelerating FGT was associated with more severe autistic symptoms,poor lung function,and increased risks of overweight/obesity.Metabolic alterations were enriched in amino acid metabolism for early decelerating and late decelerating FGTs,whereas altered metabolites were enriched in lipid metabolism for early accelerating FGT.Thesefindings suggest that FGTs are predictors of early life development and may indicate intrauterine adaptive metabolism.The discovery of optimal and suboptimal FGTs provides potential clues for the early identification and intervention of fetal origin dysplasia or disease,but further research on related mechanisms is still needed.
基金supported by the National Key Research and Development Program of China(2023YFA0915200)the National Natural Science Foundation of China(12305400,12105352)+1 种基金the Natural Science Foundation of Shanghai,China(22ZR1470600)the Xiangfu Lab Research Project(XF012022E0100).
文摘Spherical nucleic acids(SNAs)are a 3D spherical nanostructure composed of highly oriented,dense layers of oligonucleotides conjugated to a hollow or solid core.This structure allows SNAs to show resistance to nuclease degradation,enter into nearly all cells without transfection agents and enable precise interactions with target molecules.Based on superior biological properties,SNAs can be tailored for diverse biological applications,rendering them a flexible and biosafe tool for biological applications as well as an enabling platform for therapy.In this review,we mainly discuss the structure and conjugation mode of SNAs and focus on recent advances in their applications,such as biomedical detection,imaging,and drug delivery.Finally,the remaining challenges and future directions of SNAs are also discussed and proposed.
文摘The effect of reactive element yttrium on purification and carbide precipitation of superalloy K4169 has been studied through vacuum induction melting.The results show that yttrium has a strong deoxidizing and desulfurizing ability,and the impurity elements of sulfur and oxygen in melting K4169 are greatly reduced to 2-5 ppm and 4-5 ppm,respectively.The metallurgical reaction product is mainly Y_(2)O_(3)and yttrium containing sulfides have not been observed.With the increase of the content of yttrium from0.005 wt.%to 0.033 wt.%,the morphology and size of MC carbides in casting are significantly influenced due to that the yttrium changes the diffusion of the carbide forming elements and solid fraction during solidification.In the alloys without yttrium,only isolated blocky or strip carbides exist,while skeletonlike carbides are observed in the alloys with yttrium.Both the average size and the number density of skeleton carbides decrease monotonously with yttrium content increasing.After yttrium increasing to 0.033 wt.%,a phase of hexagonal Ni17 Y2 is observed to precipitate in the form of symbiosis with MC carbide and matrix.The addition of yttrium is not beneficial for the properties of K4169 alloys at the room temperature,which is quite related to the MC carbides with a large skeleton-like morphology through the analysis of tensile fracture.
