BUTYRATE SUPPLEMENTATION AFFECTS mRNA ABUNDANCE OF GENES INVOLVED IN GLYCOLYSIS, OXIDATIVE PHOSPHORYLATION AND LIPOGENESIS IN THE RUMEN EPITHELIUM OF HOLSTEIN DAIRY COWS

Abstract

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.

Integration of lncRNA and mRNA Transcriptome Analyses Reveals Genes and Pathways Potentially Involved in Calf Intestinal Growth and Development during the Early Weeks of Life

“…Moreover, rumen lncRNAs play potential roles in the regulation of pathways involving energy sources (oxidative phosphorylation pathway), cell signaling (p53 signalling or ErbB signaling) and immunity (T cell receptor signaling, Fc-γ-mediated phagocytosis and NF-κB signaling) ( Figure 4 ). The importance of these pathways in the development and functions of the rumen have been reported by several authors [ 83 , 84 , 85 ]. Perhaps, the most interesting results for rumen lncRNAs is the fact that several DE lncRNAs also potentially cis targeted mRNAs that were DE between pre- and post-weaning periods.…”

Sodium butyrate improves antioxidant stability in sub-acute ruminal acidosis in dairy goats

“…However it’s previously reported by Norton et al, that sodium butyrate infusion significantly increased rumen fluid VFA and pH [ 39 ], it is possible that butyrate altered the metabolic flux of the rumen, favoring the neutralization of H+ through the efflux of bicarbonate [ 40 ]. There are several conflicting results have been observed in previous studies about the effect of NaB on rumen pH; e, g., Laarman et al.. demonstrated the presence of SARA in both groups of cows fed a total mixed ration and concentrate with or without NaB [ 41 ], whereas Herrick et al reported a significant increase in rumen pH in lactating dairy cows ruminally dosed with butyrate [ 42 ]. Moreover, Schlau et al observed a marked increase in the molar proportion of butyrate in acidosis-resistant steers compared to that in acidosis-susceptible steers and stated that this increase may have at least partially contributed to the higher pH observed in acidosis-resistant steers [ 37 ].…”

Adaptive responses in short-chain fatty acid absorption, gene expression, and bacterial community of the bovine rumen epithelium recovered from a continuous or transient high-grain feeding

“…Additionally, the rumen epithelial (epimural) bacteria were shown to be less stable due to transient feeding (Wetzels et al, 2016), and that long-term continuously challenged epithelial microbes are significantly reduced in diversity (Wetzels et al, 2017). There are indications that the rumen epithelium elicits an adaptive response to high-grain feeding at the gene expression level by increasing barrier function (McCann et al, 2016), changing the expression of SCFA transporters and rumen epithelial cell metabolism enzymes (Laarman et al, 2013;Zhao et al, 2019), as well as inflammation-related gene expression (Zhang et al, 2016). The sensitivity of the epithelial bacterial community to changes in the diet (Petri et al, 2013a) as well as an effect of the host on the rumen microbial community (Weimer et al, 2010) might be associated with the involvement in barrier function, localized immune response, as well as SCFA transport.…”