Ruminal epithelial insulin‐like growth factor‐binding proteins 2, 3, and 6 are associated with epithelial cell proliferation

Abstract

Jacobson, & Getty, 1962). The growth of rumen papillae increases the surface area of the rumen and the absorption of short-chain fatty acids (SCFAs: acetic acid, propionic acid, and butyric acid, among others). Therefore, understanding the mechanisms of growth of rumen papillae and rumen epithelial cells is important for devising strategies to improve ruminant productivity. Previously, it was shown that rumen papillae developed remarkably when the feed was changed from milk to roughage or a concentrated diet. The growth of rumen papillae was induced by SCFAs, and butyrate was the most potent activator of rumen papillae growth (Sakata & Tamate, 1978). However, the molecular mechanism regulating the growth of rumen papillae remains unclear. Six isoforms of insulin-like growth factor-binding protein (IGFBP) are known to regulate epithelial cell proliferation and differentiation in some tissues by controlling the activity of insulin-like growth factor I (IGF-I) or insulin-like growth factor II (IGF-II) (Firth & Baxter, 2002). For example, IGFBP4 bound to IGF-I in the small intestine of mice and prevented IGF-I binding to its receptors and cell proliferation (Austin, Imam, Pintar, & Brubaker, 2015). IGFBP2 prevented cell proliferation in human embryonic kidney fibroblasts and the small intestine (Corkins,

Transcriptome Analysis of Bovine Rumen Tissue in Three Developmental Stages

“…Microbial fermentation of dietary carbohydrates in the rumen produces large amount of short-chain fatty acids (SCFAs) ( Poulsen et al, 2012 ), such as butyrate, which are known to affect rumen development and stimulate rumen epithelial cells proliferation in vivo ( Sakata and Tamate 1978 ). SCFA transport process involves many regulatory factors including insulin-like growth factor ( IGF ), sodium hydrogen exchangers ( NHE ), monocarboxylate transporters ( MCTs ), and epidermal growth factor ( EGF ), which are also involved in the regulation of rumen epithelial cell proliferation ( Baldwin 1999 ; Yang et al, 2012 ; Benesch et al, 2014 ; Nishihara et al, 2020 ). Butyrate is mainly absorbed and metabolized in the rumen epithelium ( Sehested et al, 1999 ), producing ketone body under the action of ACAT1, BDH1, HMGCS2, and HMGCL ( Kostiuk et al, 2010 ).…”

Insulin-Like Growth Factor Binding Protein 5: A Novel Regulator of Early Osteogenic Differentiation of hMSCs

“…Of the six known IGFBP family members, IGFBP5 is the most broadly bioactive and is expressed in many different cells and tissues [13,19,20]. The relationship between IGFBP5 and osteogenic differentiation, however, remains to be fully clari ed.…”

“…Insulin-like growth factor-binding proteins (IGFBPs) are pivotal regulators of the mitogenic activity of Insulin-like growth factors (IGFs) [11], are closely linked to differentiation, proliferation and invasion [12,13]. IGFBP5 is the most highly conserved IGFBP family member among vertebrates, and controls cellular growth, cell fate determination, and tumor cell metastasis [14].…”

LncRNA-mRNA modules involved in goat rumen development: Insights from genome-wide transcriptome profiling

“…As previously explored, IGF-1 can up-regulate the expression of cyclin D1 through the Ras/Raf/MEK/ERK signaling pathway and regulate the proliferation of rumen epithelial cells ( Lu et al, 2013 ). The reduced expression of IGFBP may promote the proliferation of rumen epithelial cells by promoting IGF-1 ( Nishihara et al, 2020 ). Several genes have been revealed to be associated with the growth of ruminal papillae, such as sodium butyrate infusion regulates monocarboxylate transporter isoform 1 ( MCT1 ), 3-hydroxy-3-methylglutaryl-CoA synthase isoform 2 ( HMGCS2 ), 3-hydroxy-3-methylglutaryl-CoA lyase ( HMGCL ) and sodium/proton exchanger isoform 2 ( NHE2 ) ( Sun et al, 2018 ; Liu et al, 2019 ).…”