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Holger Martens - One of the best experts on this subject based on the ideXlab platform.
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na transport across Rumen Epithelium of hay fed sheep is acutely stimulated by the peptide igf 1 in vitro
Experimental Physiology, 2012Co-Authors: Zanming Shen, Holger Martens, Monika SchweigelrontgenAbstract:An energy-rich diet leads to enhanced ruminal Na+ absorption, which is associated with elevated plasma insulin-like growth factor 1 (IGF-1) levels and an increased number of IGF-1 receptors in Rumen papillae. This study examined the in vitro effect of IGF-1 on Na+ transport across the Rumen Epithelium of hay-fed sheep, in which the IGF-1 concentration in plasma is lower than in concentrate-fed animals. At concentrations ranging from 20 to 100 μg l−1, serosal LR3-IGF-1, a recombinant analogue of IGF-1, rapidly (within 30 min) stimulated the mucosal-to-serosal Na+ flux (JmsNa) and consequently the net Na+ flux (JnetNa). Compared with controls, JnetNa increased by about 60% (P < 0.05) following the serosal application of LR3-IGF-1 (20 μg l−1). The IGF-1-induced increment of JmsNa and JnetNa was inhibited by mucosal amiloride (1 mmol l−1). Neither IGF-1 nor amiloride altered tissue conductance or the short-circuit current of the isolated Rumen Epithelium. These data support the assumption that the stimulating effect of serosally applied IGF-1 on Na+ transport across the Rumen Epithelium is mediated by Na+–H+ exchange (NHE). A further study was performed with cultured Rumen epithelial cells and a fluorescent probe (BCECF) to estimate the rate of pHi recovery after acid loading. The pHi of isolated Rumen epithelial cells was 6.43 ± 0.15 after butyrate loading and recovered by 0.26 ± 0.02 pH units (15 min)−1. Application of LR3-IGF-1 (20 μg l−1) significantly increased the rate of pHi recovery to 0.33 ± 0.02 pH units (15 min)−1. Amiloride administration reduced the recovery rate in both control and IGF-1-stimulated cells. These results show, for the first time, that an acute effect of IGF-1 on Na+ absorption across Rumen Epithelium results from increased NHE activity. Insulin-like growth factor 1 is thus important for the fast functional adaptation of ruminal Na+ transport via NHE.
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an energy rich diet enhances expression of na h exchanger isoform 1 and 3 messenger rna in Rumen Epithelium of goat
Journal of Animal Science, 2012Co-Authors: W Yang, Zanming Shen, Holger MartensAbstract:Rumen epithelial Na + /H + exchanger (NHE) catalyzes the exchange of extracellular Na + for intracellular H. Thus, it is of importance in the main- tenance of Na and pH homeostasis of Rumen epithelial cells. We have tested the hypothesis that an increase in energy and protein intake induces alterations of NHE isoform 1, 2, and 3 (NHE1, NHE1, and NHE3, respec- tively) mRNA abundance in the Rumen Epithelium of goats. Goats (n = 26) were randomly allocated to 2 ex- periments (n = 16 in Exp. 1, and n = 10 in Exp. 2) and fed either peanut straw ad libitum (PNS, n = 8 in Exp. 1, and n = 5 in Exp. 2; 600 kJ of ME/(kg 0.75 ∙d)) or PNS + concentrate (CF, n = 8 in Exp. 1, and n = 5 in Exp. 2; 1,000 kJ of ME/(kg 0.75 ∙d)) for 42 d. Concentrate (400 g/d) was giv en daily (0800 to 1700 h) in 4 equal por- tions at 3-h intervals. In Exp. 1, the goats were eutha- nized 2 h after the last portion of concentrate was fed, and in Exp. 2, the goats were euthanized after a fasting period of 16 h. In Exp. 1, goats in the CF treatment ex- hibited a greater ruminal short-chain fatty acid (SCFA) concentration (140.6 ± 1.30 mM) compared with those in the PNS treatment (114.3 ± 3.11 mM; P < 0.001), and pH decreased from 6.9 ± 0.09 to 5.9 ± 0.04 (P < 0.001). Correspondingly, the mRNA expression of NHE1 and NHE3 in the Rumen Epithelium was greater by 20% (P = 0.041) and 25% (P = 0.043) for goats in the CF treatment than for those in the PNS treatment. However, in Exp. 2, 16 h of fasting abolished differ- ences in ruminal SCFA concentration, pH, and NHE mRNA expression between goats in the CF and PNS treatments. In both Exp. 1 and 2, a positive correlation was observed between ruminal SCFA concentration and expression of mRNA in NHE1 and NHE3, whereas expression was negatively correlated with ruminal pH. In in vitro studies with isolated Rumen epithelial cells from goats fed dried grass, exposure to pH of 6.8 or to 20 mM SCFA increased (P < 0.01) NHE1 and NHE3 mRNA expression, as compared with exposure to pH of 7.4 or the absence of SCFA. A combination of reduced pH (6.8) and SCFA (20 mM) further enhanced (P < 0.05) NHE1 and NHE3 mRNA expression, indicating synergism between an increased concentration of SCFA and low pH (P < 0.05). Messenger RNA expression of NHE2 did not vary in vitro with pH (6.8) or SCFA (20 mM) or in vivo in Exp. 1 and 2. Thus, diet-dependent Rumen epithelial NHE1 and NHE3 expression is prob- ably related to ruminal SCFA concentration and pH, but that is not the case with NHE2.
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ammonia and urea transport across the Rumen Epithelium a review
Animal Health Research Reviews, 2006Co-Authors: Khalid A Abdoun, Friederike Stumpff, Holger MartensAbstract:The transport of nitrogen across the Rumen Epithelium is characterized by absorption of ammonia from the Rumen and by an influx of urea into the Rumen. The transport rates of both compounds are large and exhibit wide variation. The transport of ammonia occurs in two forms: in the lipophilic form as NH3, the magnitude of which is linearly related to the pH in the ruminal fluid at pH values above 7, while at a physiological pH of 6.5 or lower, ammonia is predominantly absorbed as NH4 + via putative potassium channels in the apical membrane. The uptake of NH4 + depends on the potential difference of the apical membrane, Pda, and shows competition with K uptake. The pathway for basolateral exit of NH4 + is unknown. Hence, the relative transport rates of NH3 or NH4 + are determined by the ruminal pH according to the Henderson‐Hasselbalch equation. Transport of ammonia interacts with the transport of Na and Mg mainly via changes of the intracellular pH. Urea recycling into the Rumen has been known for many years and the transport across the Rumen Epithelium is mediated via urea transporters in the luminal and basolateral membrane of the Epithelium. Transport of urea occurs by simple diffusion, but is highly variable. A significant increase of urea influx is caused by the fermentation products CO2 and short-chain fatty acids. Conversely, there is some evidence of inhibition of urea influx by ruminal ammonia. The underlying mechanisms of this modulation of urea transport are unknown, but of considerable nutritional importance, and future research should be directed to this aspect of ruminal transport.
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interaction between ammonia sodium and chloride transport across the Rumen Epithelium in sheep
Small Ruminant Research, 2006Co-Authors: Khalid A Abdoun, Katarina Wolf, Holger MartensAbstract:Abstract The effect of increasing mucosal ammonia concentration [0 (control), 5, 15 and 30 mmol/l NH 4 Cl] on the electrophysiology of isolated Rumen Epithelium and the transport of Na + and Cl − across it were studied, in vitro. Seventy-three isolated Rumen Epithelium samples from 14 sheep of different breeds, age and sex and solely fed on hay were used in this study. The presence of ammonia in the incubation solution on the mucosal side evoked a positive short-circuit current ( I sc ) and increased the transepithelial conductance ( G t ). The unidirectional flux rates of Na + were significantly ( p − were significantly ( p + /H + and Cl − /HCO 3 − exchangers of the Rumen Epithelium, probably by binding intracellular protons, thus elevating intracellular pH (pH i ) and consequently inhibiting Na + transport and stimulating Cl − transport across the isolated Rumen Epithelium of sheep. Inhibition of Na absorption could increase the osmolality of the Rumen fluid, which has been reported to be a predisposing factor of diet-induced left displacement in the abomasum. Further, the increased osmolality of the Rumen fluid could adversely affect the microbial growth and fermentation in the Rumen.
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effects of diet and osmotic pressure on na transport and tissue conductance of sheep isolated Rumen Epithelium
Experimental Physiology, 2006Co-Authors: Ulrike Lodemann, Holger MartensAbstract:The intention of this study was to determine the effects of mucosal osmotic pressure on transport and barrier functions of the Rumen Epithelium of sheep, which were fed various diets: hay ad libitum, or 600, 1200 or 1800 g day−1 of a supplemented diet plus hay ad libitum. The experiments were conducted by using the conventional Ussing chamber technique. Mucosal osmolarity was adjusted to 300 (control), 375 or 450 mosmol l−1. Feeding of a supplemented diet led to a significant increase of mucosal to serosal Na+ transport and net Na+ transport, probably because of an increase of apical Na+–H+ exchange activity. An increase in mucosal osmotic pressure: (a) reduced net Na+ transport in all feeding groups, the remaining net Na+ transport being higher in tissues of sheep fed a supplemented diet; (b) increased transepithelial tissue conductance, this rise being smallest with a high intake of the supplemented diet; and (c) enhanced the serosal to mucosal Na+ transport in tissues of hay-fed sheep and sheep fed with 600 g day−1 of the supplemented diet, while higher intakes of the supplemented diet (1200 and 1800 g) did not produce any effect. All these changes indicate a diet-dependent adaptation to luminal hypertonicity.
Benhai Xiong - One of the best experts on this subject based on the ideXlab platform.
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thiamine supplementation facilitates thiamine transporter expression in the Rumen Epithelium and attenuates high grain induced inflammation in low yielding dairy cows
Journal of Dairy Science, 2017Co-Authors: L Yang, Yves Beckers, Linshu Jiang, Zhiwen Tang, Benhai XiongAbstract:ABSTRACT An experiment was conducted to uncover the effects of increasing dietary grain levels on expression of thiamine transporters in ruminal Epithelium, and to assess the protective effects of thiamine against high-grain-induced inflammation in dairy cows. Six Rumen-fistulated, lactating Holstein dairy cows (627 ± 16.9 kg of body weight, 180 ± 6 d in milk; mean ± standard deviation) were randomly assigned to a replicated 3 × 3 Latin square design trial. Three treatments were control (20% dietary starch, dry matter basis), high-grain diet (HG, 33.2% dietary starch, DM basis), and HG diet supplemented with 180 mg of thiamine/kg of dry matter intake. On d 19 and 20 of each period, milk performance was measured. On d 21, ruminal pH, endotoxic lipopolysaccharide (LPS), and thiamine contents in Rumen and blood, and plasma inflammatory cytokines were detected; a Rumen papillae biopsy was taken on d 21 to determine the gene and protein expression of toll-like receptor 4 (TLR4) signaling pathways. The HG diet decreased ruminal pH (5.93 vs. 6.49), increased milk yield from 17.9 to 20.2 kg/d, and lowered milk fat and protein from 4.28 to 3.83%, and from 3.38 to 3.11%, respectively. The HG feeding reduced thiamine content in Rumen (2.89 vs. 8.97 μg/L) and blood (11.66 vs. 17.63 μg/L), and the relative expression value of thiamine transporter-2 (0.37-fold) and mitochondrial thiamine pyrophosphate transporter (0.33-fold) was downregulated by HG feeding. The HG-fed cows exhibited higher endotoxin LPS in Rumen fluid (134,380 vs. 11,815 endotoxin units/mL), and higher plasma concentrations of lipopolysaccharide binding protein and pro-inflammatory cytokines when compared with the control group. The gene and protein expression of tumor necrosis factor α (TNFα), IL1B, and IL6 in Rumen Epithelium increased when cows were fed the HG diet, indicating that local inflammation occurred. The depressions in ruminal pH, milk fat, and protein of HG-fed cows were reversed by thiamine supplementation. Thiamine supplementation increased thiamine contents in Rumen and blood, and also upregulated the relative expression of thiamine transporters compared with the HG group. Thiamine supplementation decreased ruminal LPS (49,361 vs. 134,380 endotoxin units/mL) and attenuated the HG-induced inflammation response as indicated by a reduction in plasma IL6, and decreasing gene and protein expression of pro-inflammatory cytokines in Rumen Epithelium. Western bottling analysis showed that thiamine suppressed the protein expression of TLR4 and the phosphorylation of nuclear factor kappa B (NFκB) unit p65. In conclusion, HG feeding inhibits thiamine transporter expression in ruminal Epithelium. Thiamine could attenuate the epithelial inflammation during high-grain feeding, and the protective effects may be due to its ability to suppress TLR4-mediated NFκB signaling pathways.
Edenio Detmann - One of the best experts on this subject based on the ideXlab platform.
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effects of grain processing methods on the expression of genes involved in volatile fatty acid transport and ph regulation and keratinization in Rumen Epithelium of beef cattle
PLOS ONE, 2018Co-Authors: Pedro Del Bianco Benedeti, B C Silva, M V C Pacheco, Nicola Vergara Lopes Serao, Ivan Carvalho Filho, M M Lopes, M I Marcondes, Hilario Cuquetto Mantovani, Sebastiao De Campos Valadares Filho, Edenio DetmannAbstract:Two experiments were carried out to evaluate the effects of corn and sorghum with different processing methods on the expression of genes involved in volatile fatty acids transport and pH regulation, and ruminal keratinization in Rumen Epithelium of finishing bulls. For Exp. 1, five Rumen cannulated Nellore bulls were used in a 5x5 Latin square arrangement, with 14 d for adaptation and 9 d for sample collection. Treatments were: dry ground corn, dry ground sorghum, reconstituted corn, reconstituted sorghum, and control (forage-based diet). Samples of Rumen Epithelium from ventral sac were excised, rinsed, snap-frozen and stored at -80°C until total RNA isolation and quantitative real-time PCR analysis. In the Exp. 2, 24 Nellore bulls were assigned to a completely randomized design lasting 168 d. Experimental treatments were similar to those at Exp. 1, but without the control treatment. After the experimental period, bulls were slaughtered and Rumen Epithelium samples were rapidly excised for further histological analysis. Rumen epithelial tissue from animals fed reconstituted corn had lower expression of downregulated-in-adenoma (P = 0.03) and Na+/H+ exchanger 2 (trend; P = 0.09). The expression of Na+/ H+ exchanger 1 (P = 0.10) and putative anion transporter (P = 0.06) tended to be lower in Rumen Epithelium of bulls fed reconstituted grains. Ruminal concentration of valerate was greater for animals fed reconstituted grain (P = 0.01). Likewise, animals fed reconstituted corn tended to have greater butyrate ruminal concentration (P = 0.08). Keratinized layer thickness did not differ among treatments (P > 0.10). Therefore, reconstituted grains (especially corn) decrease the mRNA expression of genes involved in volatile fatty acids transport and pH control in the Rumen Epithelium.
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Effect of ingredients and processing methods on relative mRNA expressions of genes involved in volatile fatty acids transport in Rumen Epithelium of Nellore bulls.
2018Co-Authors: Pedro Del Bianco Benedeti, Nicola Vergara Lopes Serao, Ivan Carvalho Filho, Hilario Cuquetto Mantovani, Sebastiao De Campos Valadares Filho, Breno De Castro Silva, Marcos Vinícius Carneiro Pacheco, Mariana Mescouto Lopes, Marcos Inácio Marcondes, Edenio DetmannAbstract:Effect of ingredients and processing methods on relative mRNA expressions of genes involved in volatile fatty acids transport in Rumen Epithelium of Nellore bulls.
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Mechanisms of volatile fatty acid transport through Rumen and proteins involved in pH control of Rumen Epithelium [Adapted from Stevens and Hume [30] and Connor et al. [5]].
2018Co-Authors: Pedro Del Bianco Benedeti, Nicola Vergara Lopes Serao, Ivan Carvalho Filho, Hilario Cuquetto Mantovani, Sebastiao De Campos Valadares Filho, Breno De Castro Silva, Marcos Vinícius Carneiro Pacheco, Mariana Mescouto Lopes, Marcos Inácio Marcondes, Edenio DetmannAbstract:Genes with lower expression in the Rumen Epithelium of animals fed reconstituted corn are presented in orange [DRA (P = 0.03), and NHE2 (trend; P = 0.09)]. Genes that tended to have lower mRNA expression in the Rumen Epithelium of animals fed reconstituted grains are presented in green [NHE1 (P = 0.10), and PAT1 (P = 0.06)]. AE2 = anion exchanger 2; DRA = downregulated in adenoma; MCT1 = monocarboxylate transporter 1; MCT4 = monocarboxylate transporter 4; NHE1 = Na+/H+ exchanger 1; NHE2 = Na+/H+ exchanger 2; NHE3 = Na+/H+ exchanger 3; PAT1 = putative anion transporter; H+ATPase = vacuolar-type ATPase.
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nellore bulls bos taurus indicus with high residual feed intake have increased the expression of genes involved in oxidative phosphorylation in Rumen Epithelium
Animal Feed Science and Technology, 2018Co-Authors: P Del Bianco Benedeti, Hilario Cuquetto Mantovani, Edenio Detmann, Sarah Figueiredo Martins Bonilha, Nick V L Serao, Deborah Romaskevis Gomes Lopes, Weverson Junio Da Silva, C J Newbold, M S DuarteAbstract:Abstract The objective of this study was to investigate the expression of genes involved in energy metabolism and volatile fatty acids (VFA) and urea transport in Rumen Epithelium of bulls with different feed efficiency based on residual feed intake (RFI). Twenty-seven Nellore bulls (age = 22.5 ± 0.8 mo; initial body weight = 401 ± 42 kg) were classified as either Low, Medium, and High (n = 9 per group) RFI and finished in individual pens. During the finishing phase animals were fed the same diet formulated to meet the requirements of 1.3 kg daily gain with a target finish weight of 550 kg. At the end of the trial, bulls were slaughtered and ruminal fluid was collected for further VFA analyses. Samples of Rumen Epithelium from ventral sac were rapidly excised, rinsed with phosphate buffered saline solution (pH = 7.04) and immediately immerged in RNA later solution within 2 mL tubes. After 48 h, Rumen Epithelium samples were placed at −80 °C until total RNA isolation and qPCR analysis. Data were analyzed using SAS 9.4 with α = 0.05; trends were determined as 0.10 > P > 0.05. The concentrations of total VFA, acetate, propionate, butyrate, valerate, isobutyrate, isovalerate, and acetate: propionate ratio did not differ ( P > 0.05) among RFI groups. The mRNA abundance of UQCR10 ( P NDUFB4 (trend; P = 0.07) were greatest for High RFI animals. However, the mRNA abundance of ATP5H , COX10 , and SDHF2 did not differ ( P > 0.05) among treatments. No differences ( P > 0.05) were observed for mRNA abundance of genes associated with ion pumping ( ATP1B1 , ATP1B2 , ATP1B3 ), protein turnover ( IGF1R , MKI67 , UBA1 ), heat production ( UCP2 ), butyrate metabolism ( BDH1 , BDH2 , HMGCL , HMGS1 ), and VFA ( CA7 , DRA , NHE2 , MCT1 , and PAT1 ) and urea transport ( AQP3 , AQP7 , AQP8 , AQP10 , and SLC14A1 ) in Rumen Epithelium of bulls classified as High, Medium, and Low RFI. These findings may indicate that more efficient animals (Low and Medium RFI) have lower energy expenditure in this tissue, which likely contribute for their better efficiency compared to the less efficient (High RFI) bulls.
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Effects of grain processing methods on the expression of genes involved in volatile fatty acid transport and pH regulation, and keratinization in Rumen Epithelium of beef cattle - Fig 1
2018Co-Authors: Pedro Del Bianco Benedeti, Nicola Vergara Lopes Serao, Ivan Carvalho Filho, Hilario Cuquetto Mantovani, Sebastiao De Campos Valadares Filho, Breno De Castro Silva, Marcos Vinícius Carneiro Pacheco, Mariana Mescouto Lopes, Marcos Inácio Marcondes, Edenio DetmannAbstract:A—Effect of ingredients and processing methods on keratinization in Rumen Epithelium of Nellore bulls. B—Longitudinal section from Rumen tissue of Nellore bulls fed dry ground corn, dry ground sorghum, reconstituted corn, and reconstituted sorghum, showing the normal histology of these animals. Standard error of the mean, 4.37; Ingredient P-value, 0.45; Processing method P-value, 0.83; Ingredient x Processing method P-value, 0.47 (Fisher’s least significant difference test).
B W Mcbride - One of the best experts on this subject based on the ideXlab platform.
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butyrate supplementation affects mrna abundance of genes involved in glycolysis oxidative phosphorylation and lipogenesis in the Rumen Epithelium of holstein dairy cows
American Journal of Animal and Veterinary Sciences, 2013Co-Authors: A H Laarman, Ousama Alzahal, M A Steele, Louis Dionissopoulos, S L Greenwood, J C Matthews, B W McbrideAbstract:Energy availability in epithelial cells is a crucial link for maintaining epithelial barrier integrity; energy depletion is linked to impaired barrier function in several epithelia. This study aimed to elucidate the effects of exogenous butyrate on mRNA abundance of genes indirectly involved in Rumen epithelial barrier integrity. Sixteen mid-lactation Holstein cows fed a total mixed ration received a concentrate mix to induce Subacute Ruminal Acidosis (SARA). For 7 days, while being fed the concentrate mix, cows were assigned either a control treatment or a butyrate treatment, in which cows were fed butyrate at 2.5% daily dry matter intake in the form of a calcium salt. On days 6 and 7, Rumen pH was measured continuously and on day 7, Rumen biopsies took place. Rumen pH fell below 5.6 for more than 3 hours per day in both treatments, con-firming the occurrence of SARA. Microarray and pathway analysis, confirmed by real time PCR, showed that exogenous butyrate significantly increased the mRNA abundance of hexokinase 2 (fold change: 2.07), pyruvate kinase (1.19), cytochrome B-complex 3 (1.18) and ATP Synthase, F0 subunit (1.66), which en-code important glycolytic enzymes. Meanwhile, butyrate decreased mRNA abundance of pyruvate dehydrogenase kinase 2(-2.38), ATP citrate lyase (-2.00) and mitochondrial CoA transporter (-2.27), which en-code enzymes involved in lipogenesis. These data suggest exogenous butyrate induces a shift towards energy mobilization in the Rumen Epithelium, which may aid barrier function in the Rumen Epithelium during SARA.
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butyrate and subacute ruminal acidosis affect abundance of membrane proteins involved with proton and short chain fatty acid transport in the Rumen Epithelium of dairy cows
American Journal of Animal and Veterinary Sciences, 2013Co-Authors: A H Laarman, Ousama Alzahal, M A Steele, Louis Dionissopoulos, S L Greenwood, B W McbrideAbstract:The objective of this study was to elucidate the effects of butyrate on the Short Chain Fatty Acids (SCFA) membrane transport proteins and proton membrane transport proteins in the Rumen Epithelium. Sixteen mid-lactation cows were fed a 44% Non-Fibre Carbohydrate (NFC) diet and divided into a control treatment and a butyrate treatment. For 7 days, the cows on the control treatment received a carrier treatment and the cows on the butyrate treatment received a ruminal butyrate dose at the rate of 2.5% of Dry Matter Intake (DMI). Rumen pH was measured on days 6 and 7 and Rumen biopsies were taken on days 1 and 7. Rumen pH measurements confirmed the occurrence of ruminal acidosis in both treatment groups, defined as a Rumen pH of 5.6 for at least 3 h per day. Between the control and butyrate treatment, there was no difference in Rumen pH profile. Immunofluorescence analysis performed on longitudinal ruminal papillae cross-sections showed that for the duration of the study, protein abundance in the stratum basale increased for Monocarboxylate Cotransporter Isoform 1 (MCT1), sodium/proton exchanger isoform 3 (NHE3) and sodium/Bicarbonate Cotransporter Isoform 1 (NBC1). There was a time*treatment interaction for MCT1 and NBC1, with the butyrate treatment group showing a higher abundance of MCT1 and a lower abundance of NBC1 at day 7. Luminal butyrate appears to increase SCFA uptake capacity by increasing the abundance of MCT1 transport proteins on the basolateral membrane and decreasing basolateral bicarbonate uptake capacity through decreased NBC1 protein expression. These effects decrease bicarbonate uptake capacity through NBC1 and help to offset the increased MCT1, since MCT also creates alkalotic pressure by expelling protons from the cytosol.
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Bovine Rumen Epithelium undergoes rapid structural adaptations during grain-induced subacute ruminal acidosis.
American journal of physiology. Regulatory, integrative and comparative physiology, 2011Co-Authors: M A Steele, Jim Croom, Melissa Kahler, Kees Plaizier, Sarah E Hook, Ousama Alzahal, B W McbrideAbstract:Alterations in Rumen epithelial structure and function during grain-induced subacute ruminal acidosis (SARA) are largely undescribed. In this study, four mature nonlactating dairy cattle were transitioned from a high-forage diet (HF; 0% grain) to a high-grain diet (HG; 65% grain). After feeding the HG diet for 3 wk, the cattle were transitioned back to the original HF diet, which was fed for an additional 3 wk. Continuous ruminal pH was measured on a weekly basis, and Rumen papillae were biopsied during the baseline and at the first and final week of each diet. The mean, minimum, and maximum daily ruminal pH were depressed (P < 0.01) in the HG period compared with the HF period. During the HG period, SARA was diagnosed only during week 1, indicating ruminal adaptation to the HG diet. Microscopic examination of the papillae revealed a reduction (P < 0.01) in the stratum basale, spinosum, and granulosum layers, as well as total depth of the Epithelium during the HG period. The highest (P < 0.05) papillae lesion scores were noted during week 1 when SARA occurred. Biopsied papillae exhibited a decline in cellular junctions, extensive sloughing of the stratum corneum, and the appearance of undifferentiated cells near the stratum corneum. Differential mRNA expression of candidate genes, including desmoglein 1 and IGF binding proteins 3, 5, and 6, was detected between diets using qRT-PCR. These results suggest that the structural integrity of the Rumen Epithelium is compromised during grain feeding and is associated with the differential expression of genes involved in epithelial growth and structure.
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Ruminal acidosis and the rapid onset of ruminal parakeratosis in a mature dairy cow: a case report.
Acta veterinaria Scandinavica, 2009Co-Authors: M A Steele, Jim Croom, Sarah E Hook, Ousama Alzahal, B W McbrideAbstract:A mature dairy cow was transitioned from a high forage (100% forage) to a high-grain (79% grain) diet over seven days. Continuous ruminal pH recordings were utilized to diagnose the severity of ruminal acidosis. Additionally, blood and Rumen papillae biopsies were collected to describe the structural and functional adaptations of the Rumen Epithelium. On the final day of the grain challenge, the daily mean ruminal pH was 5.41+/-0.09 with a minimum of 4.89 and a maximum of 6.31. Ruminal pH was under 5.0 for 130 minutes (2.17 hours) which is characterized as the acute form of ruminal acidosis in cattle. The grain challenge increased blood beta-hydroxybutyrate by 1.8 times and Rumen papillae mRNA expression of 3-hydroxy-3-methylglutaryl-coenzyme A synthase by 1.6 times. Ultrastructural and histological adaptations of the Rumen Epithelium were imaged by scanning electron and light microscopy. Rumen papillae from the high grain diet displayed extensive sloughing of the stratum corneum and compromised cell adhesion as large gaps were apparent between cells throughout the strata. This case report represents a rare documentation of how the Rumen Epithelium alters its function and structure during the initial stage of acute acidosis.
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ruminal acidosis and the rapid onse t of ruminal parakeratosis in a
2009Co-Authors: M A Steele, Jim Croom, Sarah E Hook, Ousama Alzahal, B W McbrideAbstract:A mature dairy cow was transitioned from a high forage (100% forage) to a high-grain (79% grain) diet over seven days. Continuous ruminal pH recordings were utilized to diagnose the severity of ruminal acidosis. Additionally, blood and Rumen papillae biopsies were collected to describe the structural and functional adaptations of the Rumen Epithelium. On the final day of the grain challenge, the daily mean ruminal pH was 5.41 ± 0.09 with a minimum of 4.89 and a maximum of 6.31. Ruminal pH was under 5.0 for 130 minutes (2.17 hours) which is characterized as the acute form of ruminal acidosis in cattle. The grain challenge increased blood beta-hydroxybutyrate by 1.8 times and Rumen papillae mRNA expression of 3-hydroxy-3-methylglutaryl-coenzyme A synthase by 1.6 times. Ultrastructural and histological adaptations of the Rumen Epithelium were imaged by scanning electron and light microscopy. Rumen papillae from the high grain diet displayed extensive sloughing of the stratum corneum and compromised cell adhesion as large gaps were apparent between cells throughout the strata. This case report represents a rare documentation of how the Rumen Epithelium alters its function and structure during the initial stage of acute acidosis.
L Yang - One of the best experts on this subject based on the ideXlab platform.
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thiamine supplementation facilitates thiamine transporter expression in the Rumen Epithelium and attenuates high grain induced inflammation in low yielding dairy cows
Journal of Dairy Science, 2017Co-Authors: L Yang, Yves Beckers, Linshu Jiang, Zhiwen Tang, Benhai XiongAbstract:ABSTRACT An experiment was conducted to uncover the effects of increasing dietary grain levels on expression of thiamine transporters in ruminal Epithelium, and to assess the protective effects of thiamine against high-grain-induced inflammation in dairy cows. Six Rumen-fistulated, lactating Holstein dairy cows (627 ± 16.9 kg of body weight, 180 ± 6 d in milk; mean ± standard deviation) were randomly assigned to a replicated 3 × 3 Latin square design trial. Three treatments were control (20% dietary starch, dry matter basis), high-grain diet (HG, 33.2% dietary starch, DM basis), and HG diet supplemented with 180 mg of thiamine/kg of dry matter intake. On d 19 and 20 of each period, milk performance was measured. On d 21, ruminal pH, endotoxic lipopolysaccharide (LPS), and thiamine contents in Rumen and blood, and plasma inflammatory cytokines were detected; a Rumen papillae biopsy was taken on d 21 to determine the gene and protein expression of toll-like receptor 4 (TLR4) signaling pathways. The HG diet decreased ruminal pH (5.93 vs. 6.49), increased milk yield from 17.9 to 20.2 kg/d, and lowered milk fat and protein from 4.28 to 3.83%, and from 3.38 to 3.11%, respectively. The HG feeding reduced thiamine content in Rumen (2.89 vs. 8.97 μg/L) and blood (11.66 vs. 17.63 μg/L), and the relative expression value of thiamine transporter-2 (0.37-fold) and mitochondrial thiamine pyrophosphate transporter (0.33-fold) was downregulated by HG feeding. The HG-fed cows exhibited higher endotoxin LPS in Rumen fluid (134,380 vs. 11,815 endotoxin units/mL), and higher plasma concentrations of lipopolysaccharide binding protein and pro-inflammatory cytokines when compared with the control group. The gene and protein expression of tumor necrosis factor α (TNFα), IL1B, and IL6 in Rumen Epithelium increased when cows were fed the HG diet, indicating that local inflammation occurred. The depressions in ruminal pH, milk fat, and protein of HG-fed cows were reversed by thiamine supplementation. Thiamine supplementation increased thiamine contents in Rumen and blood, and also upregulated the relative expression of thiamine transporters compared with the HG group. Thiamine supplementation decreased ruminal LPS (49,361 vs. 134,380 endotoxin units/mL) and attenuated the HG-induced inflammation response as indicated by a reduction in plasma IL6, and decreasing gene and protein expression of pro-inflammatory cytokines in Rumen Epithelium. Western bottling analysis showed that thiamine suppressed the protein expression of TLR4 and the phosphorylation of nuclear factor kappa B (NFκB) unit p65. In conclusion, HG feeding inhibits thiamine transporter expression in ruminal Epithelium. Thiamine could attenuate the epithelial inflammation during high-grain feeding, and the protective effects may be due to its ability to suppress TLR4-mediated NFκB signaling pathways.
