Plasma Diamine Oxidase Activity Research Articles

Yinchenhao Decoction mitigates intestinal impairment induced by high carbohydrate diet in largemouth bass (Micropterus salmoides): insights from inflammation, apoptosis, oxidative stress, tight junctions, and microbiota homeostasis.

As a major source of energy, carbohydrates have a protein-saving effect. However, excessive consumption of carbohydrates can lead to the disruption of the intestinal barrier in fish, especially for carnivorous fish. Therefore, traditional Chinese medicine component Yinchenhao Decoction (YD), was used to detect the effect on intestinal barriers and microbial community equilibrium for largemouth bass in current research. In this research, a series of NC (normal carbohydrate diet) and HC (high carbohydrate diet) with graded YD treatments during 10 weeks feeding trial. Results suggested that 2% and 4% YD treatments significantly reduced gut inflammation and mucosal loss caused by HC. Compared with NC, HC significantly decreased the relative expression of intestinal tight junction-related genes (zo1, claudin1, claudin7, and occludin). However, with the application of YD, the expression of tight junction-related genes (zo1, claudin1, and claudin7) increased significantly (p < 0.05). Likewise, administration of YD significantly reduced elevated plasma diamine oxidase (DAO) activity caused by HC (p < 0.05). Additionally, YD significantly downregulated the mRNA expression of endoplasmic reticulum stress (ERS)-related genes (grp78, atf6, chopα, ire1, xbp1, and eifα) and pro-apoptosis genes (casp3, casp8, and bax) (p < 0.05), while upregulating the anti-apoptosis gene bcl2 (p < 0.05). Moreover, YD significantly increased the mRNA expression of antioxidant genes and the enzyme activities of CAT and GPX, while decreased MDA concentration significantly (p < 0.05). Whereas, YD markedly decreased the expression of pro-inflammatory genes (il1β, tnfα, il8, and nf-κB) and the immune enzymes activity (ACP and AKP) (p < 0.05) by up-regulating the expression of anti-inflammatory genes (ikb and il10). Notably, YD modulated the largemouth bass intestinal microbial community, enhanced the diversity and increased the abundance of probiotic microorganisms in the intestinal microbiota. In summary, YD supplementation in HC alleviated inflammation, apoptosis, oxidative stress, tight-junction injury, and microbiota disequilibrium in the intestine, which suggested that YD could be a valuable functional additive in aquaculture.

Plant essential oils combined with organic acids restored lipopolysaccharide-induced leaky intestine via gut microbial modulation in weaned piglets

Intestine derived lipopolysaccharide (LPS) is closely related to systemic inflammation and disorders, yet little is known about its roles in the weanling stress of piglets and its potential as a nutritional intervention target. This study aimed to investigate the potential of essential oils (EO) and organic acids (OA) in mitigating weaning stress in piglets by modulating the circulation of intestine derived LPS. Seventy-two weaned piglets at 21 d old with body weight of 8.12 ± 0.168 kg were randomly divided into a control group (CON) and an experimental group, each consisting of six pens with six piglets per pen, and were fed either a basal diet or a basal diet supplemented with 3 kg/t OA + 500 g/t EO (EO + OA). On the 14th day of the feeding trial, 12 weaned piglets were randomly selected from the CON group, and 6 piglets were selected from the experimental group. Based on diet composition and stress treatment, these 18 piglets were divided into the following three groups: 1) CON group. Piglets were fed a basal diet and received an intraperitoneal injection of saline as a control. 2) LPS group. Piglets were fed a basal diet and received an intraperitoneal injection of LPS (100 μg/kg body weight) to induce stress. 3) EO + OA + LPS group. Piglets were fed a basal diet supplemented with EO and OA and received an intraperitoneal injection of LPS (100 μg/kg body weight) to induce stress. The results showed that EO + OA significantly ameliorated the oxidative imbalance and inflammation disorder induced by LPS in piglets' serum and intestine by inhibiting the activation of the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, compared to the LPS group, supplementation with EO + OA restored LPS-induced reductions in Bcl-2 protein expression in the piglets' intestines (P < 0.05) and mitigated morphological damage; it also enhanced both the protein expression and relative gene expression of the tight junction proteins occludin and claudin-1 (P < 0.05), and reduced the plasma diamine oxidase activity (DAO) and LPS content (P < 0.05). Compared to the CON group, supplementation with EO + OA altered the composition of the intestinal microbiota, increasing beneficial bacteria relative abundance (Faecalibacterium) (P < 0.05) and decreasing harmful bacteria relative abundance [Rikenellaceae_RC9_gut_group (P < 0.01), Negativibacillus (P < 0.05)]. Further analysis revealed that plasma LPS content in piglets was negatively correlated with the relative abundance of Faecalibacterium (r = −0.662, P = 0.021), Akkermansia (r = −0.492, P = 0.031), and average daily gain (ADG) (r = −0.912, P = 0.041). Plasma LPS content was also positively correlated with the plasma inflammatory factors interleukin (IL)-1β (r = 0.591, P = 0.021), IL-6 (r = 0.623, P = 0.021), IL-12 (r = 561, P = 0.031) contents, and the relative abundance of Negativibacillus (r = 0.712, P = 0.041). In summary, the addition of EO + OA prevents the leakage of intestine derived LPS into the circulation by improving intestinal integrity and microbiota composition, thereby enhancing antioxidant and anti-inflammatory abilities and growth performance of weaned piglets.

Effect of Supplementation with Black Soldier Fly Extract on Intestinal Function in Piglets Infected with Porcine Epidemic Diarrhea Virus.

Porcine epidemic diarrhea virus (PEDV) has developed as a global problem for the pig business, resulting in significant financial losses. Black soldier fly extract (BFE) has been proven to improve intestinal growth in pigs after weaning. Consequently, the goal of the present investigation was to explore the effects of BFE supplementation on intestinal function in PEDV-infected piglets. Eighteen piglets were randomly allocated to three groups: control, PEDV, and BFE + PEDV. The piglets in the BFE + PEDV group received 500 mg/kg BW of BFE orally for seven days from day 4 to 10 of the study. On day 9 of the study, six pigs from each group received either clean saline or PEDV solution at a dosage of 106 TCID50 (50% tissue culture infectious dose) per pig. On day 11, samples of blood and intestine were taken for additional investigation. The results indicated a significant decrease in the average daily gain (ADG) of piglets infected with PEDV (p < 0.05). Additionally, PEDV infection led to an alteration of blood indexes and a reduction in plasma D-xylose concentration and villi height in the small intestine, while it increased plasma diamine oxidase activity and small intestinal crypt depth in piglets (p < 0.05). The PEDV infection significantly reduced antioxidant enzyme activity in plasma and the gut, including total superoxide dismutase and catalase, while increasing contents of oxidation-relevant products such as malondialdehyde and hydrogen peroxide in piglets. Moreover, PEDV infection increased the mRNA expression level of antiviral-related genes (p < 0.05). Nutritional supplementation with BFE improved intestinal histomorphological indicators and reduced oxidative stress produced by PEDV infection in piglets. Interestingly, BFE could significantly promote the mRNA expression level of antiviral-related genes in the ileum (p < 0.05). Overall, the preliminary results suggest that dietary BFE could improve intestinal function in piglets after PEDV infection. Currently, the findings put a spotlight on the role of BFE in the prevention and treatment of PED in piglets.

Positive effects of selenized-oligochitosan on zearalenone-induced intestinal dysfunction in piglets.

This paper assessed the positive effects of selenized-oligochitosan (SOC) on zearalenone(ZEN)-induced intestinal dysfunction in piglets. Sixty piglets were randomly divided into 4 groups. Group C was fed the basal diet as a control and Group Z was supplemented with 2 μg/g ZEN in the basal diet; Group ZS1 and ZS2 were supplemented with 0.3 or 0.5 μg/g SOC (calculated by selenium), in addition to 2 μg/g ZEN in the basal diet. After 42 days, ileal mucosal structure, digestive enzyme activities, tight junction protein mRNA expressions, plasma D-lactate and D-xylose contents, and plasma diamine oxidase activities were determined. Compare with Group C, ileal villus height, value of villus height/crypt depth, trypsin, lipase and α-amylase activities, occluding, claudin-1 and ZO-1 mRNA expressions, and plasma D-xylose levels were significantly decreased (p < 0.01) in piglets of group Z; while compare to Group C, ileal crypt depth, plasma D-lactate contents and diamine oxidase activities were significantly increased in piglets of group Z (p < 0.01 or p < 0.05). Compare with Group Z, ileal villus height, lipase and α-amylase activities, occluding, claudin-1 and ZO-1 mRNA expressions, and plasma D-xylose levels were significantly elevated in piglets of group ZS1 and ZS2 (p < 0.01); while compare to Group Z, plasma D-lactate and diamine oxidase contents were significantly reduced in piglets of group ZS1 and ZS2 (p < 0.01 or p < 0.05). Compare with Group Z, value of villus height/crypt depth and trypsin activity were significantly promoted in piglets of group ZS2 (p < 0.01); whereas ileal crypt depth was significantly reduced in piglets of group ZS2 (p <0.01).Thus, SOC can mitigate ZEN-induced intestinal dysfunction in piglets.

Effects of different levels of dietary chlorogenic acid supplementation on growth performance, intestinal integrity, and antioxidant status of broiler chickens at an early age

This study was conducted to investigate effects of graded levels of chlorogenic acid (CGA) supplementation on growth performance, serum biochemical parameters, intestinal integrity, and antioxidant capacity of broilers at an early age. Two hundred and forty one-day-old male Arbor Acres broiler chicks were assigned to five groups with six replicates of eight birds each, and were fed a basal diet supplemented with 0 (Control group), 125, 250, 500, and 1000 mg/kg CGA for 14 days, respectively. The CGA administration linearly and quadratically increased body weight and weight gain and quadratically reduced feed conversion ratio (P < 0.05), and these effects were more pronounced when its dosage was 500 mg/kg (P < 0.05). The CGA supplementation especially at a level of 500 mg/kg linearly increased glucose concentration and quadratically lowered serum total cholesterol and triglyceride levels (P < 0.05). Dietary CGA administration linearly and quadratically reduced plasma diamine oxidase activity and D-lactate concentration (P < 0.05), and these effects were more prominent in 500 mg/kg CGA-supplemented group (P < 0.05). The CGA supplementation linearly increased the ratio between duodenal villus height and crypt depth and ileal villus height (P < 0.05). Moreover, supplementing 500 mg/kg CGA elevated the ratio of jejunal villus height and crypt depth when compared with the control group (P < 0.05). The CGA administration linearly and/or quadratically increased total antioxidant capacity (T-AOC), glutathione peroxidase, catalase, and superoxide dismutase activities and glutathione level, and decreased malondialdehyde concentration in serum, duodenum, and jejunum (except T-AOC activity and glutathione level in jejunum) (P < 0.05). Moreover, an addition of CGA linearly or quadratically increased T-AOC activity and glutathione level and reduced malondialdehyde concentration in ileum (P < 0.05). The beneficial effects of CGA on the antioxidant capacity in serum and intestinal mucosa were more apparent when its supplemental level was 500 mg/kg. The results suggested that CGA could improve growth performance, intestinal integrity, and antioxidant status of broilers at an early age, with its recommended dosage being 500 mg/kg.

Probiotic enema protects intestinal mucosa and alters plasma diamine oxidase activity among calves with diarrhea

Probiotic enema protects intestinal mucosa and alters plasma diamine oxidase activity among calves with diarrhea

An evaluation of graded levels of beta-sitosterol supplementation on growth performance, antioxidant status, and intestinal permeability-related parameters and morphology in broiler chickens at an early age

This study was designed to examine the effects of different levels of beta-sitosterol (BS) supplementation on growth performance, serum biochemical indices, redox status, and intestinal permeability-related parameters and morphology of young broilers. Two hundred and forty male Arbor Acres broiler chicks were allocated into 5 groups of 6 replicates with 8 birds each, and fed a basal diet supplemented with 0, 25, 50, 75, and 100 mg/kg BS for 21-d, respectively. The BS quadratically decreased feed conversion ratio during 1 to 14 d and 1 to 21 d, with its effect being more prominent at 25 or 50 mg/kg (P < 0.05). The BS linearly and quadratically reduced 14-d plasma diamine oxidase activity and D-lactate level, and this effect was more pronounced when its supplemental level was 25 or 50 mg/kg (P < 0.05). The BS linearly increased duodenal villus height (VH) and quadratically increased jejunal VH and ratio of VH and crypt depth (CD) at 14 d, and these effects in 25 mg/kg group were more remarkable (P < 0.05). Similarly, BS linearly or quadratically increased VH and ratio of VH and CD, but decreased CD in the jejunum and ileum at 21 d, with these effects being more pronounced at 50 mg/kg (P < 0.05). The BS supplementation especially at 50 or 75 mg/kg linearly or quadratically reduced 14-d serum and 21-d hepatic malondialdehyde concentration, and increased serum glutathione peroxidase and catalase activities at 14 and 21 d (P < 0.05). Moreover, the BS administration linearly and/or quadratically increased glutathione peroxidase, catalase, and superoxide dismutase activities and glutathione level, and reduced malondialdehyde accumulation in the intestinal mucosa at 14 and/or 21 d, and these consequences were more significant in 50 to 100 mg/kg BS-supplemented groups (P < 0.05). The results demonstrated that BS administration could improve growth performance, intestinal barrier function, and antioxidant status of broilers at an early age, with these effects being more pronounced at a level of 50 mg/kg.

Intestinal flora and immunity response to different viscous diets in juvenile largemouth bass, Micropterus salmoides

An 8-weeks feeding trial was conducted to estimate the effects of different viscous cellulose on the intestinal flora and health in juvenile largemouth bass (Micropterus salmoides). Four isoproteic and isolipidic experimental diets were formulated (crude protein 42.50%, crude lipid 13.70%) to contain 8% cellulose (control group; 5.14 mPa s), 8% low viscous carboxymethyl cellulose (CMC) with 800 mPa s (Lvs-CMC group; 182.15 mPa s), 8% middle viscous CMC with 2000 mPa s (Mvs-CMC group; 320.48 mPa s) and 8% high viscous CMC with 5000 mPa s (Hvs-CMC group; 440.65 mPa s), respectively. The weight gain rate, specific growth rate, protein efficiency ratio, protein and lipid deposition rate in the CMC groups were dramatically lower than those in the control group, while feed conversion rate showed an opposite result. Plasma diamine oxidase activity, endothelin-1 and lipopolysaccharide concentrations in the Mvs-CMC and Hvs-CMC groups were significantly higher than in the control group, accompanied by a significant down-regulation of Occludin, Caludin-1 and Caludin-4. Intestinal glutathione concentration, superoxide dismutase and catalase activities in the CMC groups were significantly lower than in the control group, accompanied by a significant up-regulation of Keap1 and down-regulation of Nrf2. Moreover, CMC diets dramatically down-regulated the expression levels of IL-10 and TGF-β1. Digesta total short chain fatty acid and acetate concentrations in the CMC groups were dramatically higher than in the control group, while butyrate concentration showed an opposite result. The OTU, Sobs, Shannon and Simpson indices of intestinal flora in the CMC groups were dramatically lower than in the control group. Notably, structural analysis showed that dietary CMC dramatically increased the abundance of C. somerae and P. shigelloides, but reduced the abundance of C. colicanis and C. perfringens. In summary, increasing dietary viscosity adversely affects the intestinal flora structure and diversity, increases acetate/butyrate-producing bacterial ratio and the abundance of pathogenic microorganisms, disrupting intestinal flora homeostasis, impairs mucosa barrier function, induces intestinal inflammation and epithelial cell apoptosis in juvenile largemouth bass. Our findings demonstrate that soluble cellulose is more detrimental to intestinal health and growth in juvenile largemouth bass compared to insoluble cellulose, and the adverse effects of soluble cellulose are mainly caused by its viscosity. Importantly, this study demonstrate that viscosity is the main characteristic of non-starch polysaccharides that are detrimental to the intestinal health of fish.

Effects of dietary non-starch polysaccharides level on the growth, intestinal flora and intestinal health of juvenile largemouth bass Micropterus salmoides

A 56-day feeding trial was conducted to evaluate the effects of dietary non-starch polysaccharide (NSPs) inclusion on the growth performance, intestinal flora and intestinal health of juvenile largemouth bass (6.00 ± 0.01 g) in quadruplicate. Seven isoproteic and isolipidic diets (crude protein 47.0%, crude lipid 12.5%) were formulated to contain 0%, 3%, 6%, 9%, 12%, 15% and 18% NSPs (each 100 g contains 32.26 g cellulose, 19.35 g arabinoxylan, 4.52 g β-glucan, 5.16 g mannan and 38.71 g pectin; named N0, N3, N6, N9, N12, N15 and N18), respectively. Weight gain rate, specific growth rate, protein efficiency ratio, protein and lipid deposition rate in the N12, N15 and N18 groups were significantly lower than in the N0 group. Plasma diamine oxidase activity and lipopolysaccharide and endothelin-1 concentration in the N15 and N18 groups were significantly higher than in the N0 group. Intestinal occludin, caludin-1, caludin-4, zonulaoccludens-1, interleukin-10, transforming growth factor-β, nuclear factor E2-related factor 2, B-cell lymphoma-2 (Bcl-2), B-cell lymphoma-xl and Bcl-2-associated athanogene expression levels and intestinal peroxidase, catalase and superoxide dismutase activities in the N15 and N18 groups were significantly lower than in the N0 group, while interleukin-8, interleukin-1β, tumor necrosis factor-α, kelch-like ECH-associated protein 1, caspase3, Bcl-2-assoxicated x protein and Bcl-2-associated death protein genes expression levels showed opposite trends. Moreover, the Shannon, Simpson, Chao and Ace indices and the abundance of Plesiomonas shigelloides, [Clostridium] dakarense and Romboutsia ilealis in the N18 group were significantly lower than in the N0 group, in contrast to the abundance of Paraclostridium bifermentans, Mycoplasma moatsii. Propionate, butyrate, valerate and total short-chain fatty acids (SCFA) contents in digesta of the N6 group were significantly higher than in the N0 group, while acetate, butyrate, valerate, caproate and total SCFA in digesta of the N18 group were significantly lower than in the N0 group. Results suggest that high NSPs diets increased intestinal permeability and abundance of pathogenic microorganisms, induced intestinal inflammation and intestinal epithelial cell apoptosis, but decreased intestinal flora α-diversity and SCFA contents, and ultimately impaired growth performance and intestinal health of juvenile largemouth bass. Conversely, low-dose NSPs inclusion had no negative effect on growth and improves intestinal health in juvenile largemouth bass, showing potential as prebiotics in aquafeed.

Effects of cottonseed protein concentrate on growth performance, hepatic function and intestinal health in juvenile largemouth bass, Micropterus salmoides

The study aimed to evaluate the effect of replacing fish meal (FM) by cottonseed protein concentrate (CPC) on growth, immune respone and health status of largemouth bass, Micropterus salmoides. Fish (initial body weight: 12.21 ± 0.15 g) were fed five isonitrogenous and isolipid diets (48% crude protein and 12% crude lipid) with CPC replacing 0 (control, CPC0), 15% (CPC15), 30% (CPC30), 45% (CPC45) or 60% (CPC60) of fishmeal for 8 weeks. The results showed that weight gain, specific growth rate and protein efficiency ratio were not appreciably reduced until more than 30% of the FM protein was replaced with CPC. Fish fed CPC60 diet had the lowest hepatic antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX) activities and genes (SOD, CAT, GSH-Px) expression, but the highest malondialdehyde (MDA) level. Moreover, CPC60 diet significantly down-regulated the expression of anti-inflammatory genes (IL-10, TGF-β) and protein metabolism genes (P13K, AKT, m-TOR, S6K1), whereas up-regulated the expression of pro-inflammatory genes (IL-8, IL-1β, TNFα). Accordingly, the liver histological investigation showed that the histopathological alterations were dramatically increased in the CPC60 group compared to control and CPC30 group. In addition, the CPC60 group decreased the villi height and goblet cell number, and increased villi width and muscular thickness in midgut and hindgut compared with the other groups, respectively. Meanwhile, plasma diamine oxidase (DAO) activity, D-lactate and endotoxin contents increased markedly as the proportion of CPC increased. Notably, the increased dietary CPC levels down-regulated the expression of ZO-1, Claudin-1 and Occludin in intestine. The lower SOD, CAT activities and mRNA levels in intestine were also observed in CPC60 group. Broken-line model analysis based on WG against dietary CPC replacement level indicated that the optimum replacement level was 18.44% when supplemented with crystalline methionine and lysine. However, including too high proportion of CPC could suppress immune and antioxidant capacity, impair both the liver and intestinal health, and finally reduced growth of Micropterus salmoides.

Effects of Bacillus subtilis on jejunal integrity, redox status, and microbial composition of intrauterine growth restriction suckling piglets

The present study used intrauterine growth restriction (IUGR) piglets as an animal model to determine the effect of Bacillus subtilis on intestinal integrity, antioxidant capacity, and microbiota in the jejunum of suckling piglets. In total, 8 normal birth weight (NBW) newborn piglets (1.62 ± 0.10 kg) and 16 newborn IUGR piglets (0.90 ± 0.08 kg) were selected and assigned to three groups. Piglets were orally gavaged with 10-mL sterile saline (NBW and IUGR groups), and IUGR piglets were orally gavaged with 10-mL/d bacterial fluid (B. subtilis diluted in sterile saline, gavage in the dose of 2 × 109 colony-forming units per kg of body weight; IBS group; n = 8). IUGR induced jejunal barrier dysfunction and redox status imbalance of piglets, and changed the abundances of bacteria in the jejunum. Treatment with B. subtilis increased (P < 0.05) the ratio of villus height to crypt depth (VH/CD) in the jejunum, decreased (P < 0.05) the plasma diamine oxidase (DAO) activity, and enhanced (P < 0.05) the gene expressions of zonula occludens-1 (ZO-1), occludin, and claudin-1 in the jejunum of IUGR piglets. Treatment with B. subtilis decreased (P < 0.05) the concentration of protein carbonyl (PC) and increased (P < 0.05) the activities of catalase (CAT) and total superoxide dismutase (T-SOD) in the jejunum of IUGR piglets. Treatment with B. subtilis also increased (P < 0.05) gene expressions of superoxide dismutase 1 (SOD1), CAT, and nuclear factor erythroid 2-related factor (Nrf2), as well as the protein expressions of heme oxygenase-1 (HO-1), SOD1, and Nrf2 in the jejunum of IUGR piglets. Treatment with B. subtilis also improved the abundances and the community structure of bacteria in the jejunum of IUGR piglets. These results suggested that IUGR damaged the jejunal barrier function and antioxidant capacity of suckling piglets, and altered the abundances of bacteria in the jejunum. Treatment with B. subtilis improved the intestinal integrity and antioxidant capacity while also improved the abundances and structure of bacteria in the jejunum of suckling piglets.

Resveratrol and its derivative pterostilbene ameliorate intestine injury in intrauterine growth-retarded weanling piglets by modulating redox status and gut microbiota

BackgroundIntestinal disorder is an important factor contributing to growth lag and high rates of morbidity and mortality of piglets with intrauterine growth retardation (IUGR). Resveratrol (RSV) and its derivative pterostilbene (PT) are natural stilbenes possessing various bioactivities, such as antioxidative and anti-inflammatory effects. This study compared the protective potential of RSV and PT on the intestinal redox status and gut microbiota in weanling piglets with IUGR.MethodsEighteen male piglets of normal body weight (NBW) and 54 same-sex IUGR piglets were chosen according to their birth and weaning weights. The NBW piglets accepted a basal diet, while the IUGR piglets were allotted to one of three groups according to their body weight at weaning and received a basal diet, an RSV-supplemented diet (300 mg/kg), or a PT-supplemented diet (300 mg/kg), respectively.ResultsCompared with IUGR piglets, both RSV and PT improved the IUGR-associated decrease in jejunal villus height and increases in plasma diamine oxidase activity and D-lactate level and jejunal apoptosis of piglets (P < 0.05). Administering RSV and PT also enhanced jejunal superoxide dismutase activity and the mRNA and protein expression of superoxide dismutase 2 of IUGR piglets by promoting nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation (P < 0.05). Comparatively, PT was more effective than RSV in elevating the villus height/crypt depth ratio and occludin mRNA and protein levels in the jejunum of IUGR piglets (P < 0.05). PT was also superior to RSV in increasing Nrf2 nuclear translocation and inhibiting malondialdehyde accumulation in the jejunum of IUGR piglets (P < 0.05). Additionally, RSV modulated the composition of cecal microbiota of IUGR piglets, as evidenced by increasing the prevalence of the phylum Bacteroidetes and the genera Prevotella, Faecalibacterium, and Parabacteroides and inhibiting the growth of the phylum Proteobacteria and its genera Escherichia and Actinobacillus (P < 0.05). Moreover, RSV significantly increased the butyrate concentration in the cecum of IUGR piglets (P < 0.05).ConclusionPT is more potent than RSV to prevent intestinal oxidative stress, while RSV has a stronger capacity to regulate gut microbiota compared to PT.

Plasma amino acid status is useful for understanding intestinal mucosal damage in calves with cryptosporidiosis.

We hypothesize that some amino acid abnormalities in diarrheic calves are useful for understanding intestinal mucosal damage, as in humans. However, few reports have revealed the relationship between intestinal mucosal damage and plasma amino acids in diarrheic calves. Therefore, the aim of present study was to investigate whether there is a relationship between the amino acid status and plasma diamine oxidase (DAO) activity, which is known to be a biomarker for intestinal mucosal damage in diarrheic calves. Twenty Holstein calves aged 12.6 ± 4.2days old were enrolled in this study. In the diarrhea group (n = 10), there were yellow loose feces within the rectum and Cryptosporidium parvum (C. parvum) was detected in all fecal samples. These calves were clinically normal except for diarrhea. All calves in the control group (n = 10) appeared to be healthy based on clinical findings with normal feces production and the absence of C. parvum. Plasma amino acid concentrations and DAO activity were measured. The relationships between plasma DAO activity and the concentration of each plasma amino acid were investigated using Spearman's rank test. The plasma DAO activity was significantly lower in the diarrhea group (176.1 ± 60.1IUmL-1) than in the control group (309.3 ± 74.8IUmL-1) (p < 0.001). Furthermore, positive correlations were observed when comparing plasma DAO activity with histidine, proline, cystine, arginine, and glutamine concentrations. As a result of relationship between plasma DAO activity and amino acid status, it was concluded that plasma amino acid status is useful for understanding intestinal mucosal damage in calves with cryptosporidiosis.

27-Hydroxycholesterol contributes to cognitive deficits in APP/PS1 transgenic mice through microbiota dysbiosis and intestinal barrier dysfunction

BackgroundResearch on the brain-gut-microbiota axis has led to accumulating interest in gut microbiota dysbiosis and intestinal barrier dysfunction in Alzheimer’s disease (AD). Our previous studies have demonstrated neurotoxic effects of 27-hydroxycholesterol (27-OHC) in in vitro and in vivo models. Here, alterations in the gut microbiota and intestinal barrier functions were investigated as the possible causes of cognitive deficits induced by 27-OHC treatment.MethodsMale APP/PS1 transgenic and C57BL/6J mice were treated for 3 weeks with 27-OHC (5.5 mg/kg/day, subcutaneous injection) and either a 27-OHC synthetase inhibitor (anastrozole, ANS) or saline. The Morris water maze and passive avoidance test were used to assess cognitive impairment. Injuries of the intestine were evaluated by histopathological examination. Intestinal barrier function was assessed by plasma diamine oxidase (DAO) activity and d-lactate. Systemic and intestinal inflammation were evaluated by IL-1β, TNF-α, IL-10, and IL-17 concentrations as determined by ELISA. The fecal microbiome and short-chain fatty acids (SCFAs) were analyzed using 16S rDNA sequencing and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Tight junction proteins were evaluated in the ileum and colon by qRT-PCR and Western blots. Tight junction ultrastructure was examined by transmission electron microscopy.ResultsTreatment with 27-OHC resulted in severe pathologies in the ileum and colon. There was impaired intestinal barrier integrity as indicated by dilated tight junctions and downregulation of tight junction proteins, including occludin, claudin 1, claudin 5, and ZO-1, and signs of inflammation (increased IL-1β, TNF-α, and IL-17). Fecal 16S rDNA sequencing and taxonomic analysis further revealed a decreased abundance of Roseburia and reduced fecal levels of several SCFAs in 27-OHC-treated mice. Meanwhile, co-treatment with ANS reduced intestinal inflammation and partially preserved intestinal barrier integrity in the presence of 27-OHC.ConclusionsThe current study demonstrates for the first time that 27-OHC treatment aggravates AD-associated pathophysiological alterations, specifically gut microbiota dysbiosis and intestinal barrier dysfunction, which suggests that the gut microbiome and intestinal barrier function warrant further investigation as potential targets to mitigate the neurotoxic impact of 27-OHC on cognitive function and the development of AD.

Plasma histidine concentrations as a specific biomarker for intestinal mucosal damage in calves with cryptosporidiosis

Specific alterations in plasma histidine concentrations and diamine oxidase (DAO) activity were recently reported as a potential biomarker for intestinal mucosal damage in diarrheic calves. However, there are no data on the comparison of precision between histidine concentration and DAO activity in bovine plasma. The aim of the present study was to compare precision of histidine concentrations and DAO activities in plasma as a biomarker for the Cryptosporidium parvum (C. parvum)-associated intestinal mucosal damage in diarrheic calves. Thirty-two Holstein calves aged 12.2 ± 4.1 days old were enrolled in the present study; they were divided into C. parvum (n = 9), diarrhea (n = 11), and control (n = 12) groups based on the presence or absence of diarrhea and with or without C. parvum infection. Receiver operating characteristic (ROC) curves were used to characterize the sensitivity and specificity of each parameter for the C. parvum-associated intestinal mucosal damage. The proposed cut-off points for plasma histidine concentrations and plasma DAO activities for cryptosporidiosis in calves based on ROC analyses were < 55.8 nM and < 246.0 IU/ml, respectively. The sensitivities and specificities of the proposed diagnostic cut-offs were 88.9% and 82.6% for plasma histidine concentrations and 100.0% and 34.8% for plasma DAO activities, respectively. It was concluded that plasma histidine concentrations may be superior to plasma DAO activities as a specific biomarker for the C. parvum-associated intestinal mucosal damage in diarrheic calves.

Simple, sensitive and specific quantification of diamine oxidase activity in complex matrices using newly discovered fluorophores derived from natural substrates

ObjectiveTo measure diamine oxidase (DAO) activity with high sensitivity in complex matrices like plasma or tissue extracts radioactive putrescine or horseradish peroxidase (HRP)/hydrogen peroxide (H2O2) coupling must be used. The use of radioactive material should be avoided and HRP/H2O2 coupling is compromised by antioxidants.Methods and resultsCondensation of ortho-aminobenzaldehyde (oABA) with delta-1-pyrroline and delta-1-piperideine, the autocyclization products of the DAO-oxidized natural substrates putrescine and cadaverine, generates new quinazoline fluorophores with absorption and excitation maxima of 430 and 460 nm, respectively, and peak emission at 620 nm. Fluorescent-based detection limits are 20–40 times lower compared to absorption measurements. This assay can be used to measure DAO activity in human plasma after spiking recombinant human (rh)DAO, in rat plasma after intravenous rhDAO administration, in pregnancy plasma and in tissue extracts of DAO wild-type and knock-out mice. Using rat plasma the correlation between rhDAO activity and ELISA data is 99%. Human and rat plasma without DAO spiking and tissue extracts from DAO knock-out mice showed stable and low fluorescence in the presence of high substrate concentrations.ConclusionsIncubation of DAO with the natural substrates putrescine and cadaverine and oABA generates novel fluorophores increasing the detection limit compared to absorption measurements at least tenfold. This simple, sensitive and specific assay allows the non-radioactive quantification of DAO activity in complex matrices like plasma and tissue extracts without interference by antioxidants.

Comparison of the protective effects of resveratrol and pterostilbene against intestinal damage and redox imbalance in weanling piglets

BackgroundEvidence indicates that early weaning predisposes piglets to intestinal oxidative stress and increases the risk of intestinal dysfunction; however, there are minimal satisfactory treatment strategies for these conditions. This study investigated the potential of resveratrol and its analog, pterostilbene, as antioxidant protectants for regulating intestinal morphology, barrier function, and redox status among weanling piglets.MethodsA total of 144 piglets were selected at 21 days of age and randomly allocated into one of four treatment groups, each of which included six replicates. Piglets in a sow-reared control group were suckling normally between ages 21 and 28 days, while those in weaned groups were fed a basal diet, supplemented with either 300 mg/kg of resveratrol or with 300 mg/kg of pterostilbene. Parameters associated with intestinal injury and redox status were analyzed at the end of the feeding trial.ResultsEarly weaning disrupted the intestinal function of young piglets, with evidence of increased diamine oxidase activity and D-lactate content in the plasma, shorter villi, an imbalance between cell proliferation and apoptosis, an impaired antioxidant defense system, and severe oxidative damage in the jejunum relative to suckling piglets. Feeding piglets with a resveratrol-supplemented diet partially increased villus height (P = 0.056) and tended to diminish apoptotic cell numbers (P = 0.084) in the jejunum compared with those fed a basal diet. Similarly, these beneficial effects were observed in the pterostilbene-fed piglets. Pterostilbene improved the feed efficiency of weanling piglets between the ages of 21 and 28 days; it also resulted in diminished plasma diamine oxidase activity and D-lactate content relative to untreated weaned piglets (P < 0.05). Notably, pterostilbene restored jejunal antioxidant capacity, an effect that was nearly absent in the resveratrol-fed piglets. Pterostilbene reduced the malondialdehyde and 8-hydroxy-2´-deoxyguanosine contents of jejunal mucosa possibly through its regulatory role in facilitating the nuclear translocation of nuclear factor erythroid-2-related factor 2 and the expression levels of NAD(P)H quinone dehydrogenase 1 and superoxide dismutase 2 (P < 0.05).ConclusionsThe results indicate that pterostilbene may be more effective than its parent compound in alleviating early weaning-induced intestinal damage and redox imbalance among young piglets.

Effect of electroacupuncture on intestinal epithelial mucosal barrier function in rats with diarrhea-predominant irritable bowel syndrome

To observe the effect of electroacupuncture (EA) on intestinal epithelial mucosal barrier function in diarrhea-predominant irritable bowel syndrome(IBS-D) rats, so as to explore its mechanisms underlying improvement of IBS-D. Forty SD rats (half male and half female) were randomly divided into control, model, EA and medication (Pinaverium Bromide, PB) groups, with 10 rats in each group. The IBS-D model was established by chronic unpredictable mild stress combined with gavage of Senna-leaf solution. EA (2 Hz/15 Hz，0.1-1 mA) was applied to unilateral "Zusanli"(ST36),"Tianshu" (ST25), "Sanyinjiao"(SP6) and "Taichong"(LR3) alternatively for 15 min, once daily for 14 days. Rats of the medication group was treated by gavage of PB (10 mL·kg-1·d-1) for 14 days. The visceral sensitivity (pain) was assessed by using the pressure threshold which the inserted rectal balloon catheter air-inflation (connected to a blood pressure gauge) induced stronger abdominal muscular contraction to force the rat's abdomen to lift the experimental stand surface. The diarrhea index was used to evaluate loose stool grade. The expression of Claudin-1 and Occludin (intestinal epithelial tight junction proteins) of colon tissue was detected by immunohistochemistry. The activity of plasma diamine oxidase (DAO) was assayed by using spectrophotometry. Compared with the control group, the diarrhea index and plasma DAO activity in the model group were significantly increased (P<0.01), while the visceral pain threshold, expression of Claudin-1 and Occludin in the model group were significantly decreased (P<0.01). After the treatment, the diarrhea index and plasma DAO activity were significantly lower in both EA and medication groups than that in the model group (P<0.01), and the visceral pain threshold and expression levels of Claudin-1 and Occludin were obviously increased (P<0.05, P<0.01). No significant differences were found between the EA and medication groups in all the above-mentioned indexes (P>0.05). Electroacupuncture can significantly improve abdominal pain and diarrhea in IBS-D model rats, which may be closely associated with its effects in up-regulating the expression of intestinal epithelial tight junction proteins Claudin-1 and Occludin to restore the function of intestinal epithelial mucosal barrier.

Influence of Mushroom Polysaccharide, Nano-Copper, Copper Loaded Chitosan, and Lysozyme on Intestinal Barrier and Immunity of LPS-mediated Yellow-Feathered Chickens.

Simple SummaryRecently, there has been an increasing worldwide interest in limiting or banning the use of synthesized antibiotic growth promoters used in animal production, so as to avoid the development of the drug resistance of human pathogens. This is accelerating the efforts of scientists to present new, natural and safe antibiotic alternatives that are adequate for animal and poultry production. This study contributes by evaluating some potent antibiotic alternatives in growing yellow feathered chicks, including mushroom polysaccharides, nano-copper, copper loaded chitosan, and lysozyme, versus a common antibiotic (Aureomycin). The dietary addition of the tested substances has demonstrated several beneficial effects, particularly in the case of polysaccharides (100 mg/kg) and lysozyme (500 mg/kg), on jejunal barrier, and immunity of yellow-feathered chicks aged 4–24 days, with comparable effects to the antibiotic treatment.This study investigated the influence of dietary supplementation with some antibiotic alternatives on growth performance, intestinal barrier, and immunity of lipopolysaccharide (LPS) challenged chicks. Wenshi females, aged 4 days, were allocated randomly into eight groups, each with six replicates of 20 birds (n = 120/treatment), which received a basal diet supplemented with 0 (control), 0 (LPS), 200 mg/kg aureomycin, 50 mg/kg mushroom polysaccharide, 100 mg/kg mushroom polysaccharide, 500 mg/kg nano-copper, 300 mg/kg copper loaded chitosan, and 500 mg/kg lysozyme for 21 days. On day 18 and 20, the control birds were injected with 0.5 mL saline solution, the other treatments were injected with 0.5 mL saline containing 500 µg LPS/kg body weight (BW). The results indicated that LPS treatment reduced the BW, average daily gain (ADG), and daily feed intake (ADFI) than the controls (p < 0.05), and the antibiotic and the tested alternatives could not retrieve the normal BW, ADG, and ADFI. The tested additives reduced several negative effects of LPS; they reduced diamine oxidase activity and inflammatory mediators in plasma, jejunal mucosa, spleen and thymus, increased content of immunoglobulin in plasma and jejunal mucosa, and decreased gene expression of inducible nitric oxide synthase and Cyclooxygenase 2 in jejunal mucosa.

Dietary corn resistant starch regulates intestinal morphology and barrier functions by activating the Notch signaling pathway of broilers.

ObjectiveThis study was conducted to investigate the effects of dietary corn resistant starch (RS) on the intestinal morphology and barrier functions of broilers.MethodsA total of 320 one-day-old broilers were randomly allocated to 5 dietary treatments: one normal corn–soybean (NC) diet, one corn–soybean–based diet supplementation with 20% corn starch (CS), and 3 corn–soybean–based diets supplementation with 4%, 8%, and 12% corn resistant starch (RS) (identified as 4% RS, 8% RS, and 12% RS, respectively). Each group had eight replicates with eight broilers per replicate. After 21 days feeding, one bird with a body weight (BW) close to the average BW of their replicate was selected and slaughtered. The samples of duodenum, jejunum, ileum, caecum digesta, and blood were collected.ResultsBirds fed 4% RS, 8% RS and 12% RS diets showed lower feed intake, BW gain, jejunal villus height (VH), duodenal crypt depth (CD), jejunal VH/CD ratio, duodenal goblet cell density as well as mucin1 mRNA expressions compared to the NC group, but showed higher concentrations of cecal acetic acid and butyric acid, percentage of jejunal proliferating cell nuclear antigen-positive cells and delta like canonical Notch ligand 4 (Dll4), and hes family bHLH transcription factor 1 mRNA expressions. However, there were no differences on the plasma diamine oxidase activity and D-lactic acid concentration among all groups.ConclusionThese findings suggested that RS could suppress intestinal morphology and barrier functions by activating Notch pathway and inhibiting the development of goblet cells, resulting in decreased mucins and tight junction mRNA expression.