Induction of the BCMO1 gene during the suckling-weaning transition in rats is associated with histone H3 K4 methylation and subsequent coactivator binding and histone H3 acetylation to the gene.

The cells involved in nutrient absorption in the small intestine of rats undergo rapid maturation during the suckling-weaning transition period, i.e., 2-4 wk after birth.

Changes in mucosal alpha-glucosidase activities along the jejunal-ileal axis by an Hm-HACS diet intake are associated with decreased lipogenic enzyme activity in epididymal adipose tissue.

Heat-moisture (hm)-high-amylose corn starch (HACS), which includes a larger amount of resistant starch than HACS or regular cornstarch (CS), is more indigestible in the small intestine than HACS or CS. An hm-HACS diet was also shown to ameliorate glucose intolerance and lipid abnormalities. This study examined the effects of feeding rats an hm-HACS diet for 14 days on the activities of mucosal alpha-glucosidase along the jejunal-ileal axis and lipogenic enzymes in epididymal adipose tissue.

Feeding rats a high fat/carbohydrate ratio diet reduces jejunal S/I activity ratio and unsialylated galactose on glycosylated chain of S-I complex.

Aims: We examined whether decreasing jejunal sucrase/isomaltase (S/I) activity ratio by feeding rats a high fat/carbohydrate ratio diet is regulated by changing glycosylated chains on the S-I complex.

Main Methods: Jejunal activities of sucrase, isomaltase and beta-1,4-galactosyltransferase were examined in rats fed a high fat/carbohydrate or a low fat/carbohydrate ratio diet. The amount of galactose and mannose in the glycosylated chain on the S-I complex in rats fed both diets was determined using RCA(120) and Con A lectins, respectively.

Higher expression of jejunal LPH gene in rats fed the high-carbohydrate/low-fat diet compared with those fed the low-carbohydrate/high-fat diet is associated with in vitro binding of Cdx-2 in nuclear proteins to its promoter regions.

It has been previously demonstrated that the expression of lactase-phlorizin hydrolase (LPH) and sucrase-isomaltase (SI) genes are higher in rats fed a high-carbohydrate/low-fat (HCT) diet than in those fed a low-carbohydrate/high-fat (LCT) diet. In the present study, using a nuclear run-on assay we clearly show that higher expression of LPH and SI genes in jejunum of rats fed the HCT diet compared with those fed a LCT diet was regulated at the transcription levels. DNase I foot printing analysis of the 5' flanking region of the rat LPH gene demonstrated that by incubating the jejunal nuclear extract the protected region was conserved as the same sequence as the homeodomain protein-binding element designated as CE-LPH1.

Distribution and dietary induction of cellular retinol-binding protein type II along the villus-crypt axis of the rat jejunum.

Cellular retinol-binding protein type II (CRBPII) is exclusively expressed in the small intestinal absorptive cells. We previously reported that dietary fat induces CRBPII expression within 12 h of fat intake. To examine at which locus of the villus-crypt axis this response to dietary fat occurs, 6-wk-old rats were fed a low-fat diet (7% energy) for 7 d, and then given free access to a high-fat diet (70% energy) for the subsequent 12, 24 or 48 h.

Possible role of fatty acids in milk as the regulator of the expression of cytosolic binding proteins for fatty acids and vitamin A through PPARalpha in developing rats.

Fatty acids in milk are thought to play an important role in intestinal maturation and gene expression in the postnatal small intestine. In this study, we determined the jejunal mRNA levels, in rats, of peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARdelta which are nuclear receptors for fatty acids. We also measured expression of their target genes during the postnatal period, namely liver type fatty acid-binding protein (L-FABP) and cellular retinol-binding protein, type II (CRBPII).

Fatty acids in component of milk enhance the expression of the cAMP-response-element-binding-protein-binding protein (CBP)/p300 gene in developing rats.

Fatty acids in milk are thought to play an important role in intestinal maturation and gene expression in the rat small intestine during the suckling-weaning period. In the present study, we determined the jejunal mRNA level of the cAMP-response-element-binding-protein-binding protein (CBP)/p300, which is one of the chromatin remodelling factors and regulates histone acetylation, during the postnatal period in rats. The mRNA level of CBP/p300 was high during the suckling and middle of the weaning period (day 5 to 20) and then declined sharply to a low level at the end of the weaning period and after weaning.

Developmental changes in gene expressions of beta-carotene cleavage enzyme and retinoic acid synthesizing enzymes in the chick duodenum.

Vitamin A is derived from provitamin A carotenoids, mainly beta-carotene, by beta-carotene 15,15'-monooxygenase (BCMO1; EC 1.13.11.

Selectivity of fatty acid ligands for PPARalpha which correlates both with binding to cis-element and DNA binding-independent transactivity in Caco-2 cells.

It is thought that peroxisome proliferator-activated receptor alpha (PPARalpha) is a major regulator for fatty acid metabolism. Long-chain fatty acids have been shown to induce expression of the genes related to fatty acid metabolism through PPARalpha. However, it is unclear whether the intensity of PPARalpha activation is different among various fatty acids.

Diet-related variation in cellular retinol-binding protein type II gene expression in rat jejunum.

Cellular retinol-binding protein type II (CRBPII) is involved in the transport of vitamin A and its metabolism in the small intestine. In the present study, we demonstrated diet-related variations in CRBPII expression in rat jejunum. The CRBPII protein and mRNA levels increased in parallel after the start of feeding period regardless of whether the feeding period was restricted to the hours of darkness or of light.

Developmental changes of the expression of the genes regulated by retinoic acid in the small intestine of rats.

Retinoic acid (RA) serves as a hormone-like nutrient and it plays pivotal roles in cellular differentiation and proliferation in various tissues including the small intestine. In this study, we aimed to explore a possible role of RA signaling in the developing rat small intestine of perinatal (embryonic and newborn) and suckling-weaning transition period, and we investigated the changes in the expression of several genes regulated by RA. Northern blot analysis showed that both retinal dehydrogenase 1 (RALDH1) and retinal dehydrogenase 2 (RALDH2) mRNA levels were higher in 19-day fetal (2 days before birth) small intestine and then declined after birth.

Postnatal changes in gene expression of retinal dehydrogenase and retinoid receptors in liver of rats.

Retinoic acid (RA) plays important roles in cellular differentiation and proliferation in various tissues including the liver. To explore a possible role of RA in the postnatal development of hepatic function, we analyzed RA-generation enzyme activity and the RA-related hepatic gene expressions in the suckling and weaning rats. At 5 days after birth, retinal dehydrogenase (RALDH) activity in the liver was relatively high.

Major intestinal coactivator p300 strongly activates peroxisome proliferator-activated receptor in intestinal cell line, Caco-2.

We have previously reported that several genes related to intestinal fatty acid and vitamin A metabolism are coordinately regulated by peroxisome proliferator-activated receptor (PPAR) [Arch. Biochem. Biophys.