Lentiviral vector-mediate ATG3 overexpression inhibits growth and promotes apoptosis of human SKM-1 cells

Based on the nested case–control study cohort and gene expression profile, we have picked up a subset of six genes to distinguish the leukemia group and control group stably. ATG3 is the only down regulated gene. This research is to investigate the effect of ATG3 gene over expression by lentivirus on SKM-1 cell line and myelodysplastic syndrome to leukemic transformation. Human SKM-1 cells were transfected with ATG3–GFP recombinant lentiviral vectors and compared with cells transfected with GFP lentiviral vectors. Western blot was performed to detect the ATG3 protein. Cell proliferation was assessed by cell counting kit-8. Cell vitality was tested by Trypan Blue. Cell apoptosis was determined by Annexin V Apoptosis Detection Kit APC. Observe and compare the changes on growth curve, cell vitality and cell apoptosis. After 72 h of transfection, satisfactory transfection efficiency (> 90 %) was observed. SKM-1 cell line showed a statistically significant (P < 0.05) overexpression of ATG3, parallel to significantly (P < 0.05) inhibited cell proliferation. The cell vitality of ATG3 overexpression was significantly (P < 0.05) lower than negative control. Cell apoptosis analysis by flow cytometer demonstrated decreased proportion of early apoptosis and increased that of late apoptosis and death (P < 0.05). Over expressed ATG3 gene and protein, the SKM-1 cell line was inhibited in proliferation and cell vitality. It was promoted from early apoptosis to late apoptosis and death. The malignancy of SKM-1 cell line was decreased after transfection. ATG3 gene and its gene family may play an important role in transformation of myelodysplastic syndrome.     

Involvement of ZEB1 and E-cadherin in the invasion of lung squamous cell carcinoma

This study intended to investigate the expression of the ZEB1 and E-cadherin proteins in lung squamous cell carcinoma (LSCC) tissues and to examine the clinicopathological correlation between protein levels and LSCC. RT-PCR and Western blot were used to examine the expression of ZEB1 and E-cadherin mRNAs and proteins in LSCC tissues as well as in adjacent normal tissues, and then analyze the relationship between the clinicopathological characteristics and the expression changes of ZEB1 and E-cadherin mRNAs in LSCC. In addition, RNAi was used to knockdown the expression of the ZEB1 gene in Human HCC827 cells; subsequently, changes in the invasive ability of the resultant cells were studied. The positive rates of ZEB1 and E-cadherin mRNAs in LSCC tissues were 69.2 and 38.5 %, respectively. They differed significantly from the corresponding positive rates in the adjacent normal lung tissues (15.4 and 80.8 %, p < 0.05). There was a negative correlation between the protein levels of ZEB1 and E-cadherin in LSCC tissues (r = -0.714, p < 0.001); in addition, it was found that ZEB1 protein expression in LSCC tissues was significantly higher than that in the neighboring normal lung tissues (p < 0.05), and its expression was also significantly higher in patients with lymph node metastases and distant metastases compared to those patients without metastatic disease (p < 0.05). On the contrary, E-cadherin expression was significantly lower in LSCC tissues than that in the neighboring normal tissue (p < 0.05). It was lower in patients with lymph node metastasis and distant metastasis compared to patients without metastatic disease (p < 0.05). However, the expression of ZEB1 and E-cadherin was independent of gender, age, tumor size, or tumor differentiation level (p > 0.05). Transfection of ZEB1 siRNA into HCC827 cells significantly reduced the ZEB1 protein level (p < 0.01) and significantly elevated E-cadherin levels (p < 0.01). Moreover, significantly less ZEB1 siRNA-transfected cells migrated through Transwell chambers in the LSCC tissue than that in the control groups (untransfected or transfected with control siRNA, p < 0.01). The expression of the ZEB1 gene in LSCC tissues is downregulated with the expression of E-cadherin. On the other hand, the expression of siRNA against ZEB1 promotes E-cadherin expression and suppresses the invasive ability conferred by E-cadherin. In conclusion, our data suggested that overexpression of the ZEB1 gene is possibly associated with the occurrence, development, invasion of LSCC.     

Effects of chicken intestinal antimicrobial peptides on humoral immunity of chickens and antibody titres after vaccination with infectious bursal disease virus vaccine in chicken

Abstract

Sixty chickens were randomly divided into two groups (30 chickens in each group) to determine the effect of oral administration of chicken intestinal antimicrobial peptides (CIAMP) on the humoral immune response. Chickens of both groups were fed the same diet. In the treatment group chickens received drinking water supplemented with CIAMP (1 µg/ml) right after hatching. Samples of blood, bursa of Fabricus, spleen and intestine were taken at day 1, 4, 7, 10 and 17 of experiment. CIAMP supplementation enhanced the content of IgG and IgM in serum from day 4 – 10 and day 10 – 17, respectively, (p < 0.05), IgM-forming cells in bursa of Fabricus and spleen at the age of 7 days (p < 0.05) and IgG-forming cells in bursa of Fabricus at the age of 4 days (p < 0.05). In addition, CIAMP enhanced the IgA-forming cells in caecal tonsils diffuse area at day 4 (p < 0.05). Furthermore, CIAMP enhanced the antibody response to infectious bursal disease virus vaccine (IBDV) in chickens 21 days following IBDV vaccine administration (p < 0.05). These results suggested that CIAMP could modulate the humoral immune response of chickens and increased the antibody titres of infectious bursal disease virus vaccine.     

Effects of supplementing two levels of magnesium aspartate and transportation stress on pork quality and gene expression of 𝛍-calpain and calpastatin of finishing pigs

The objective of this study was to investigate the effects of supplementing swine finishing diets with two levels of magnesium aspartate (MgAsp) and short-term transportation stress on blood parameters, pork quality and the mRNA abundance of μ-calpain and calpastatin in muscles of finishing pigs. Thirty-six crossbred finishing pigs (mean BW 90 kg) were assigned randomly to 0, 1000, or 2000 mg supplemental Mg from MgAsp per kg of diet for five days before slaughter. Then six pigs from each dietary treatment were subjected either to no transportation stress (NTS) or 2 h of transportation stress (TS). Transportation stress resulted in higher concentrations (p < 0.01) of serum calcium, glucose and cortisol, lower pH (p < 0.01), higher Warner-Bratzler shear force (WBSF) (p < 0.05) and higher calpastatin mRNA abundance (p = 0.05) of longissimus muscle (LM) compared with NTS treatments. Supplementation of MgAsp in TS treatments increased serum Mg concentration (p < 0.05) at 2000 mg of Mg/kg, reduced drip loss (p < 0.05) and improved pork quality colour (p < 0.05) at 2000 mg of Mg/kg, and decreased 1-day and 3-day WBSF (p < 0.05) at 1000 mg of Mg/kg compared with TS treatments fed the control diet. It is concluded that supplementation of MgAsp improves water-holding capacity and pork colour, and alleviates the negative effects of transportation stress on meat tenderness.     

Effects of weaning age and formic acid-based feed additives on pigs from weaning to slaughter

Abstract

Two hundred and forty piglets were used in a 2×6 factorial experiment to study the effects of weaning age (26 or 36 d) and four formic acid-based feed additives on the performance of pigs from weaning to slaughter. Either formic acid (F) or a mixture of formic acid, propionic acid, and potassium sorbate (FPS) or a mixture of formic acid, propionic acid, and sodium benzoate (FPB) or formic acid in a diatomaceous earth carrier (FD) were added to the diets of weaned piglets (from weaning to 60 d of age) and growing (18 – 46 kg) and finishing pigs (46 – 107 kg) to provide 8, 6, and 6 g acid per kg feed, respectively. The negative control treatment's (C) diets contained no growth promoters, whereas the positive control treatment's weaner and grower diets were supplemented with 40 mg/kg of avilamycin (A). The piglets weaned at the age of 26 and 36 d weighed 7.6 and 10.7 kg at weaning (p < 0.001), and 18.5 and 17.9 kg at the age of 60 d (p > 0.05), respectively. There was a weaning age×feed additive interaction in the weight gain of piglets after weaning (p < 0.05). The weight gain of piglets weaned on day 26 was enhanced by A, FPS, and FD (p < 0.05), and that of piglets weaned on day 36 by A and FPB (p < 0.05). The feed conversion ratio was not affected by weaning ages but was decreased in groups A, F, FBS, and FPB (p < 0.05). The severity of post-weaning diarrhoea was less in groups A, F, FPS, and FD than in C (p < 0.05). In piglets weaned on day 26, faecal water content and the total Escherichia coli count were highest 9 d after weaning. The total E. coli count was reduced only by FD (p < 0.05). Increased faecal water content was characterized by increased faecal Na⁺ and decreased K⁺ concentrations. Weaning age did not influence performance or carcass quality in the growing-finishing pigs. Feed additives did not affect weight gain in the growing pigs, but FPS and FPB enhanced weight gain during finishing period and total fattening (p < 0.05). In summary, the pigs' growth performance from weaning to slaughter was not affected by weaning age but it was enhanced by mixtures of formic and propionic acids with small amounts of sorbate or benzoate.     

Comparative effect of different dietary inulin sources and probiotics on growth performance and blood characteristics in growing–finishing pigs

The study was focused on assessment of the effect of an extract of long-chain inulin (LCI) and dried tubers of Jerusalem artichoke (JA) and a multispecies probiotic preparation as well as a combination thereof on growth performance and blood parameters of fattening pigs. In total, 144 pigs (initial body weight 30.0 ± 0.5 kg) were used in a 98-d experiment. The six dietary treatments consisted of the control diet (Con), diet Con supplemented with probiotics (ConP) and four diets supplemented with LCI or JA alone or with probiotics (diets LCIP and JAP). Throughout the fattening period, there was a beneficial effect of the probiotic supplementation to the inulin-containing diets and the average daily gain (ADG) was increased by supplementation of probiotics in combination with inulin sources (p < 0.05). At the end of the fattening period, ADG and feed conversion ratio (FCR) were higher after supplementation of LCI only (p < 0.05). Compared with group ConP, in groups LCI and JA, the ADG and FCR were improved (p < 0.05). Only in the first fattening stage, the addition of the prebiotics and/or probiotics had an impact on the level of white blood cells and some biochemical indices in pigs. In younger animals, probiotic or LCI supplementation increased the IgG level (p < 0.05). There was also an interaction between the probiotics and JA resulting in increased IgG and IgA concentrations (p < 0.05). In the finishing period, LCI addition increased the IgM level (p < 0.05), whereas JA addition increased IgG and IgM levels as well (p < 0.05). In conclusion, both dietary sources of inulin and probiotic supplementation can improve the fattening performance and health status of growing pigs.     

Inhibitory effects of food additives derived from polyphenols on staphylococcal enterotoxin A production and biofilm formation by Staphylococcus aureus

In this study, we examined the inhibitory effects of 14 food additives derived from polyphenol samples on staphylococcal enterotoxin A (SEA) production and biofilm formation by Staphylococcus aureus. Tannic acid AL (TA), Purephenon 50 W (PP) and Polyphenon 70A (POP) at 0.25 mg/mL and Gravinol®-N (GN), Blackcurrant polyphenol AC10 (BP), and Resveratrol-P5 (RT) at 1.0 mg/mL significantly decreased SEA production by S. aureus C-29 (p < 0.05). TA, GN, BP, and RT significantly inhibited the expression of the sea gene in S. aureus C-29 (p < 0.05), while suppression attempts by PP and POP proved unsuccessful. After result analysis, it can be derived that TA, GN, BP, and RT inhibit the production of SEA. Of the six samples, each one significantly inhibited biofilm formation (p < 0.05). Food additives derived from polyphenols have viability to be used as a means to inhibit the enterotoxin production and control the biofilm formation of foodborne pathogens.     

Antioxidant and Neuroprotective Activities of Hyptis suaveolens (L.) Poit. Against Oxidative Stress-Induced Neurotoxicity

The present study was carried out to investigate the antioxidant and neuroprotective effects of Hyptis suaveolens methanol extract (HSME) using various in vitro systems. The total phenol and flavonoids contents of the HSME were quantified by colorimetric methods. The HSME extract exhibited potent antioxidant activity as determined by 2,20-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 2,2-diphenyl-1-picrylhydrazyl, and ferric reducing antioxidant power assays. The neuroprotective activity of HSME was determined on mouse N2A neuroblastoma cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lactate dehydrogenase, intracellular ROS assays, and upregulation of brain neuronal markers at genetic level. The N2A cells were pretreated with different concentrations (0.5, 1, 1.5, and 2 mg/ml) of the extract and then exposed to H₂O₂ to induce oxidative stress and neurotoxicity. The survival of the cells treated with different concentrations of HSME and H₂O₂ increased as compared to cells exposed only to H₂O₂ (47.3 %) (p < 0.05). The HSME also dose-dependently reduced LDH leakage and intracellular ROS production (p < 0.05). Pretreatment with HSME promotes the upregulation of tyrosine hydroxylase (2.41-fold, p < 0.05), and brain-derived neurotrophic factor genes (2.15-fold, p < 0.05) against H₂O₂-induced cytotoxicity in N2A cells. Moreover, the HSME showed antioxidant activity and decreased neurotoxicity. These observations suggest that HSME have marked antioxidant and neuroprotective activities.     

Influence of feeding whole sunflower seed and extruded linseed on production of dairy cows,rumen and plasma constituents,and fatty acid composition of milk

Holstein cows were fed total mixed rations (TMR) supplemented with protected palm fat (PPF), whole sunflower seed (WSS) or extruded linseed (ELS) for 100 days. Percentage of dietary crude fat was 5.3, 5.1 and 5.1, respectively. Diet had no (p > 0.05) effect on feed intake, milk yield or milk protein content. Percentage of milk fat and yield of fat – corrected milk were significantly increased when diets were supplemented with WSS and ELS. Feeding PPF resulted in the lowest (p < 0.05) ruminal concentration of volatile fatty acids. No significant dietary effect on plasma characteristics was observed. Concentration of polyunsaturated fatty acids (PUFA) was higher (p < 0.05), and PUFA n-6/n-3 ratio lower (p < 0.05), in the milk fat from cows fed ELS compared to WSS. Supplementation of TMR with oilseeds compared to PPF increased the content of CLA in milk fat (p < 0.005) and decreased its atherogenicity, primarily due to a significant reduction of palmitic acid concentration. Both oilseeds significantly improved the spreadability index of manufactured butter. ELS, but not WSS, increased the susceptibility of milk fat to oxidation (p < 0.05). It can be concluded that feeding of oilseeds to dairy cows improved nutritional quality of milk fat, with supplementation with ELS producing an even more desirable milk fatty acid profile than WSS supplementation.     

Effect of age at the beginning of the free-range fattening period on growth and carcass and fat quality in Iberian pigs

Abstract

This experiment was carried out to study the influence of age at the beginning of the free-range fattening period (traditional pigs, TP, age 12 months vs. young pigs, YP, age 8 months) on the performance of Iberian pigs. During 152 days prior to the fattening period, TP and YP pigs received 1.7 and 2.6 kg feed per day, respectively. During fattening, TP pigs had a higher average daily gain (p < 0.05) than YP pigs. The proportions of PUFA and n-3 fatty acids of the outer and inner layers of subcutaneous backfat were higher in TP than in YP pigs (p < 0.05), while the proportions of C16:0 and SFA in the inner layer of subcutaneous backfat were greater in YP than in TP pigs (p < 0.05). The ratio of n-6/n-3 in subcutaneous backfat was lower in TP than in YP pigs (p < 0.05). The percentage of intramuscular fat in longissimus dorsi muscle was higher in TP than in YP pigs (p < 0.05). The relationship between the percentage of intramuscular fat in longissimus dorsi muscle and average daily gain during the free-range fattening period adjusted to a quadratic function (p < 0.05). The concentration of α- and γ-tocopherol in subcutaneous backfat at slaughter was significantly higher in TP than in YP pigs (p < 0.05). It is concluded that Iberian pigs that have 8 months of age at the beginning of free-range feeding have adequate commercial quality.     

In vitro fermentation of various carbohydrate-rich feed ingredients combined with chyme from pigs

Increased carbohydrate fermentation, compared with protein fermentation, could benefit gut health. In two in vitro experiments, the effect of carbohydrate-rich feed ingredients on fermentation characteristics of ileal chyme from pigs was assessed, using the cumulative gas production technique. Ingredients of the first experiment included gums, inulins, pectins, transgalacto-oligosaccharides, lactose and xylan. In the second experiment, a gum, pectin and transgalacto-oligosaccharides were added at different starting weights, to determine their effects on fermentation characteristics of chyme, in relation to differences in the carbohydrate concentrations. In comparison to fermentation of chyme alone, added carbohydrates led to higher total gas production (p < 0.05), faster maximum rate of gas production (except for xylan) (p < 0.05), and a decreased branched-chain fatty acids to straight chain fatty acids ratio (BCR) (p < 0.05). In the second experiment, for all carbohydrate ingredients, the BCR decreased with increasing starting weights (p < 0.05). If these supplemented dietary carbohydrates were to reach the terminal ileum of the living animal, carbohydrate fermentation in the large intestine could be stimulated, which is known to have beneficial effects on host health.     

Efficacy of dietary supplemental insoluble fibrous materials in ameliorating adverse effects of coccidial challenge in broiler chickens

ABSTRACT

The current experiment was designed to examine effects of dietary supplemental sunflower hulls (SH) and rice hulls (RH) on growth performance, carcass traits, intestinal morphology, lesion score and oocyst shedding in broiler chickens exposed to coccidial challenge. A total of 540 broiler chickens (Ross 308) were assigned to six dietary treatments based on a factorial arrangement (2 × 3) across 1–14, 14–28 and 28-42-d periods. Experimental treatments consisted of broiler chickens without or with coccidial challenge each offered with three different diets: a basal diet or basal diet supplemented with either RH or SH at 40 g/kg diet, respectively. Infection with Eimeria impaired daily weight gain (DWG) and feed conversion ratio (FCR) of broiler chickens during growing period (p < 0.05) while supplementation of SH or RH reduced the adverse effect of coccidiosis so that birds had similar DWG to those fed the basal diet without infection. However, only dietary SH improved the FCR of broilers challenged with coccidiosis. Regardless of coccidial challenge, dietary access to insoluble fibre improved performance of broilers across the growing period (p < 0.05); however, this effect was not observed during the entire rearing period. Relative weights of liver and pancreas were increased in birds subjected to coccidial challenge on d 21 of age (p < 0.05). Moreover, relative weights of the intestinal segments were enhanced (p < 0.05). Furthermore, gizzard weights were higher in birds receiving diets added with fibre (p < 0.05). Infection with coccidiosis decreased villus height and villus height to crypt depth ratio in duodenum of broilers which received the basal diet compared with those fed the same feed without coccidial challenge (p < 0.05). However, supplemental SH could decrease the negative effect of infection on the noted intestinal morphometric attributes. Similarly, a marked reduction was observed for lesion score and faecal oocyst excretion of challenged broilers fed on dietary supplemental fibre (p < 0.05). In conclusion, supplementation of insoluble fibre could ameliorate negative effects of coccidial challenge on DWG of broiler chickens and inclusion of SH in diet of birds exposed to Eimeria infection could be recommended.     

Nutritional and physiological responses of finishing pigs exposed to a permanent heat exposure during three weeks

The aim of the current study was to investigate the effect of a permanent heat exposure during 21 days on pig performance, nutrient digestibility, physiological response and key enzyme of skeletal muscle energy metabolism. Twenty-four male finishing pigs (crossbreed castrates, 79.0 ± 1.50 kg body weight) were allocated to three groups (n = 8): (1) Control (ambient temperature (AT) 22°C, ad libitum feeding), (2) Group HE (AT 30°C, ad libitum feeding) and (3) Group PF (AT 22°C, pair-fed to Group HE). The permanent heat exposure decreased feed intake (p < 0.01), daily body weight gain (p < 0.05) and the digestibility of gross energy, dry matter, crude protein and ash (p < 0.05); rectal temperature and respiration rate were significantly increased (p < 0.01). The levels of plasma cortisol, creatine kinase and lactate dehydrogenase were also significantly increased in Group HE (p < 0.05). Furthermore, the heat exposure changed intracellular energy metabolism, where the AMP-activated protein kinase was activated (p = 0.02). This was combined with changes in parameters of glycolysis such as an accumulation of lactic acid (p = 0.02) and a drop of pH_24?h (p = 0.02), an increase of hexokinase and pyruvate kinase activity (p < 0.01) and, finally, the maturation process of post mortem muscle was influenced. Due to pair-feeding it was possible to evaluate the effects of heat exposure, which were not dependent on reduced feed intake. Such effects were, e.g., reduced nutrient digestibility and changed activities of several enzymes in muscle and blood serum.     

Effects of Lactobacillus casei and Enterococcus faecalis on growth performance,immune function and gut microbiota of suckling piglets

This study was carried out to investigate the effects of orally administrated Lactobacillus casei and Enterococcus faecalis on performance, immune function and gut microbiota of suckling piglets. Neonatal piglets (n = 120) were randomly assigned to 4 groups, with 30 suckling piglets in each group. The piglets were from 15 litters, one male and one female piglet were selected for each group in each litter. The Control group was administrated with normal saline, the other groups with L. casei or E. faecalis or a combination of L. casei and E. faecalis at a ratio of 3:1. Each piglet was orally administrated with 1, 2, 3 and 4 ml probiotics or normal saline at the age of 1, 7, 14 and 21 d, respectively. The piglets were weaned at the age of 21 d. The results showed that compared with the Control group, the average daily gain of piglets administrated with probiotics was significantly increased, and the diarrhoea rate and mortality were significantly decreased (p < 0.05). After supplementation of the combined probiotics, the protease activity in stomach, duodenum and colon was increased and in all supplemented groups, the immunoglobulin A concentration in plasma was significantly higher (p < 0.05). The combined probiotics significantly increased villus length and the expression level of transforming growth factor-β in the jejunum (p < 0.05) but decreased the expression level of the jejunal tumour necrosis factor-α (p < 0.05). In addition, probiotics could regulate gut microbiota and increase microbial similarity coefficients for keeping piglet gut microbiota stable.     

Effects of keratinase supplementation of corn-soybean meal based diets on apparent ileal amino acid digestibility in growing pigs and serum amino acids,cytokines, immunoglobulin levels and loin muscle area in nursery pigs

Two experiments were conducted to evaluate effects of keratinase for growing and nursery pigs. In Exp. 1, six pigs (32.3 ± 2.8 kg body weight), fitted with a simple T-cannula at the distal ileum, were assigned to one of two 3 × 3 Latin squares involving three periods and three diets including a basal diet and the same diets supplemented with 0, 0.05 or 0.1% keratinase. Dietary keratinase supplementation increased the apparent ileal digestibility of crude protein (CP), arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, alanine, glutamic acid and proline (p < 0.05). Digestibility coefficients did not differ between pigs fed 0.05 and 0.1% keratinase. In Exp. 2, 24piglets weaned at 30 ± 2 d of age were used in a 2 × 2 factorial design experiment with two CP concentrations (19 vs. 22%) and two levels of keratinase supplementation (0 vs. 0.05%). Keratinase supplementation increased (p < 0.05) average daily gain, serum arginine concentration and loin muscle area but decreased (p < 0.05) serum interleukin-10 concentrations. The reduction in dietary CP level decreased (p < 0.05) serum urea nitrogen concentrations, isoleucine, serine and proline concentrations, but increased serum arginine concentrations. Few interactions between keratinase supplementation and dietary CP concentration were observed. This study indicated that dietary keratinase supplementation improved apparent ileal amino acid digestibility for growing pigs and had a positive effect on weight gain, immune response and loin muscle area for nursery pigs.     

Influence of supplemental endoglucanase or xylanase on volatile fatty acid production from ruminant feed by ruminal in vitro cultures

Abstract

This study employed two commercial enzyme preparations to examine the effects of endoglucanase, xylanase or their combination on in vitro volatile fatty acid (VFA) production by ruminal microbial populations. Batch ruminal cultures were established with one of various feedstuffs or with a fescue hay-based diet and ruminal fluid from a heifer fed a 40% forage:60% concentrate diet. Addition of xylanase at 135 xylanase units (XU) per ml increased total VFA production from the fescue hay-based diet (44.3 vs. 57.2 mM, p < 0.05) without changing the acetate to propionate (A:P) ratio. Addition of endoglucanase at 2, 3, 4, and 5 carboxymethyl cellulase units (CMCU) per ml increased total VFA production from the fescue hay-based diet on average by 36% (p < 0.05). Addition of 3, 4 and 5 CMCU/ml also decreased (p < 0.05) the A:P ratio. The combined addition of xylanase (135 XU/ml) and endoglucanase (5 CMCU/ml) increased total VFA production from the fescue hay-based diet (40.9 vs. 61.5 mM, p < 0.05) and reduced the A:P ratio (3.4 vs. 1.5, p < 0.05). The effects of endoglucanase and xylanase supplementation on in vitro VFA production varied across the various substrates used. However, endoglucanase supplementation consistently reduced the A:P ratio with all substrates tested. The effects of the enzyme combination were generally greater than either enzyme alone. We conclude that endoglucanase and xylanase activities differ in their ability to affect ruminal VFA production, and endoglucanase but not xylanase, may improve fermentation efficiency by reducing the A:P ratio.     

Characterisation of particle dynamics and turnover in the gastrointestinal tract of Holstein cows fed forage diets differing in fibre and protein contents

An improved understanding of the role of forage quality on the processes of particle dynamics and turnover is important for the development of healthier and cost-effective feeding strategies that aim at lowering the proportions of concentrates in the diets of cattle. The aim of this study was to evaluate the effects of feeding hays of different qualities on particle dynamics, digestion kinetics and turnover in the gastrointestinal tract (GIT). Three non-lactating, rumen fistulated Holstein cows were fed diets consisting exclusively of hay with either low quality [Group LH; 605 ± 12.4 g/kg neutral detergent fibre (NDF) and 63 ± 4.7 g/kg crude protein (CP)] or good quality (Group GH; 551 ± 20.1 g/kg NDF and 116 ± 3.6 g/kg CP). Data showed that in situ dry matter (DM) disappearance of the soluble fraction was greater for Group GH (p < 0.05). Feeding good quality hay also lowered the proportion of particles >1.18 mm particularly during the eating process (p < 0.05). Changes in the particle size occurring afterwards were greater for Group GH as well (p < 0.05); approximately 30% in the comminution in the particle size occurred postruminally. Feeding hay of good quality lowered DM content of solid rumen digesta (p < 0.05), accelerated (p < 0.05) the turnover rate of DM and NDF in the GIT and increased DM intake (p < 0.05). In conclusion, feeding forages of better quality significantly promoted degradation processes and kinetics in the GIT with positive effects on turnover rate of digesta and feed intake in Holstein cows.     

A PKC-β inhibitor protects against cardiac microvascular ischemia reperfusion injury in diabetic rats

PKC-β inhibitor Ruboxistaurin (RBX or LY333531) can be used to reverse diabetic microvascular complication. However, it has not been previously established whether RBX can protect against ischemia/reperfusion (I/R) injury of cardiac microvessels in diabetic rats. STZ-induced diabetic rats were randomized into four groups and underwent I/R procedures. Cardiac barrier function and the region of cardiac microvascular lesion were examined. Cell monolayer barrier function was detected in cultured cardiac microvascular endothelial cells (CMECs) subjected to simulated I/R (SI/R). PKC-β siRNA was transfected into CMECs to silence PKC-β. Apoptosis Index of CMECs was detected by TUNEL assay and phosphor-LIMK2 protein expression was examined by Western blot analysis. RBX and insulin administration significantly reduced the cardiac microvascular lesion region and Apoptosis Index of endothelial cells (all P < 0.05 vs. no-treatment group). RBX decreased phosphor-LIMK2 expression (P < 0.05 vs. no-treatment group). RBX pretreatment and transfection with PKC-β siRNA induced a rapid barrier enhancement in CMECs monolayer as detected by increased transendothelial electrical resistance (TER) and decreased FITC-dextran clearance (all P < 0.05 vs. no-treatment group). Meanwhile, RBX pretreatment and transfection with PKC-β siRNA significantly decreased TUNEL positive CMECs and phosphor-LIMK2 expression in cultured CMECs (all P < 0.05 vs. no-treatment group). RBX pretreatment reduced F-actin/G-actin in cultured CMECs, reproducing the same effect as PKC-β siRNA. These data indicate that PKC-β inhibitor (RBX) may be helpful in attenuating the risk of severe cardiac microvascular I/R injury in diabetic rats partly due to its maintenance of endothelial barrier function and anti-apoptotic effect.     

Screening and test of CD40 related signal transduction pathway in AGS cells and construction of gene silencing vector

This study is designed to screen the CD40 related signal transduction pathway in AGS cells and construction of gene silencing vector. Analysis results showed 414 differential genes expression, including upregulation of 209 genes and downregulation of 205 genes. Basing on the ratio of signal in experimental group to signal in control group, 45 genes (38 genes upregulation and seven genes downregulation) with significant (P < 0.01) change in expression levels were screened according to the screening standard (signal log ratio ≥1 or ≤?1). These genes involved into metabolism, cell cycle and apoptosis, signal transduction and stress response. Furthermore, PI3K mRNA expression level in PI3K siRNA transfected AGS cells was 0.2335 ± 0.0116 72 h after transfection. This value was significantly (P < 0.05) lower than that in blank and negative control groups. PI3K protein expression in PI3K siRNA transfected AGS cells was significantly (P < 0.05) lower than that in blank and PI3K siRNA/N transfected groups. Therefore, PI3K siRNA gene silencing vector can significantly inhibit PI3K mRNA and protein expression in AGS cells.