Alterations in mRNA expression of duodenal 1,25-dihydroxyvitamin D3 receptor and vitamin D-dependent calcium binding protein in aged wistar rats

Ct, Liang; Barnes, Janice; Imanaka, Shunji; Hf, DeLuca

doi:10.1016/0531-5565(94)90049-3

Cited by 31 publications

(27 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For this reason no conclusions about pathogenesis of osteoporosis in humans may be drawn. This lack of age-dependent differences is in accordance with findings --gained with identical study design and methodology --in cattle and goat (Riner, 2006;Singer, 2006) and several other reports (Kinyamu et al, 1997;Wood et al, 1998;Lee et al, 2003;Pazianas et al, 2003;Yamagishi et al, 2006) and in contrast to data published elsewhere (Horst et al, 1990;Ebeling et al, 1992;Liang et al, 1994;Bischoff et al, 2001;Duque et al, 2002;Holick, 2003). Since an age and/or estrogen dependent impairment of calcium resorption was detectable in elder subjects in numerous studies, a resistance to vitamin D was postulated (Kinyamu et al, 1997;Wood et al, 1998) and furthermore vitamin D-dependent (Kinyamu et al, 1997;Liel et al, 1999;Schwartz et al, 2000;Leonard et al, 2001;Duque et al, 2002;Gilad et al, 2005) and independent effects of estrogens on calcium resorption were verified (Colin et al, 1999;Eisman, 2001;Van Cromphaut et al, 2003).…”

Section: Resultscontrasting

confidence: 53%

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Riner

Boos

Hässig

et al. 2007

Journal of Morphology

View full text Add to dashboard Cite

The biologically active form of vitamin D, i.e., 1,25‐dihydroxycholecalciferol or calcitriol, plays an important role in bone metabolism and calcium homeostasis, which is often disturbed at the onset of lactation in high milk‐yielding domestic ruminants. Gene transcription is modulated via vitamin D receptors, but nongenomic effects of vitamin D via membrane receptors have also been described. In the intestines, vitamin D promotes calcium absorption via vitamin D receptors. Vitamin D receptors are of clinical relevance, but have not been systematically assessed within all segments of the intestine in any species. Thus, we present for the first time an immunohistochemical study of the distribution patterns of the vitamin D receptor protein in sheep, which may be the basis for present and future investigations on mineral homeostasis in domestic ruminants. Tissue probes of the intestines were collected from five lambs and five nonlactating and nonpregnant dams, fixed in formalin, embedded in paraffin, and used for the assessment of vitamin D receptor protein. Nuclear vitamin D receptor immunoreaction was scored semiquantitatively and exhibited a segment‐specific distribution pattern. Goblet cells always were devoid of any vitamin D receptor immunoreaction. Surface epithelial cells and enterocytes of the crypt openings generally demonstrated only a weak immunoreaction. Basally and/or intermediately located crypt epithelial cells exhibited stronger immunoreactions in duodenum, jejunum, and colon descendens. This basal/intermediate to superficial gradient was most pronounced in the duodenum and less evident in jejunum and colon descendens and not observed in ileum and cecum. There were no age‐dependent variations in vitamin D receptor protein expression. Results demonstrate that intestinal vitamin D receptor distribution patterns are segment‐specific and strongest immunoreactions correlate with highest intestinal calcium absorptive activities, as reported in literature. Strong expression of vitamin D receptors within the lower half of crypts also suggests a role for calcitriol in epithelial differentiation and cellular homeostasis. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.

show abstract

Section: Resultscontrasting

confidence: 53%

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Riner

Boos

Hässig

et al. 2007

Journal of Morphology

View full text Add to dashboard Cite

show abstract

“…However, a lack of age-dependent differences was also shown in cattle and sheep [Riner, 2006;Singer, 2006] and several other reports [Kinyamu et al, 1997;Wood et al, 1998;Lee et al, 2003;Yamagishi et al, 2006]. This is in contrast to data published elsewhere [Horst et al, 1990;Ebeling et al, 1992;Liang et al, 1994;Duque et al, 2002]. Since an age-and/or estrogen-dependent impairment in calcium resorption was detectable in elder subjects in some studies, a resistance to VD was postulated [Kinyamu et al, 1997;Wood et al, 1998] and furthermore VD-dependent [Kinyamu et al, 1997;Liel et al, 1999;Schwartz et al, 2000;Duque et al, 2002] and -independent effects of estrogens on calcium resorption were verified [Eisman, 2001;van Cromphout et al, 2003].…”

Section: Discussioncontrasting

confidence: 56%

Immunohistochemical Demonstration of Vitamin D Receptor Distribution in Goat Intestines

Boos

Riner

Hässig

et al. 2007

Cells Tissues Organs

View full text Add to dashboard Cite

Vitamin D (VD) plays an important role in calcium homeostasis. 1,25-Dihydroxycholecalciferol or calcitriol modulates gene transcription via nuclear VD receptors (VDR). In the intestines, VD promotes calcium resorption via VDR. VDR has not been systematically assessed within the intestine in any species. We therefore present a semiquantitative immunohistochemical study of the distribution patterns of VDR in goat intestines. Intestinal tissue probes were collected from 5 lambs and 5 non-lactating non-pregnant dams, fixed in formalin, embedded in paraffin and assessed for VDR. Nuclear VDR immunoreaction was scored semiquantitatively. VDR exhibited a segment-specific distribution pattern. Goblet cells were always devoid of VDR. Enterocytes within the surface epithelium and the superficial crypts generally demonstrated only a weak immunoreaction along the length of the intestine, while basally and/or intermediately located crypt epithelial cells exhibited strong VDR immunoreactions in the duodenum, jejunum and colon descendens. The difference in VDR staining between deep and superficial locations was most prominent in the duodenum and less evident in the jejunum, ileum and colon descendens. Results demonstrate that VDR distribution exhibits cell type-, segment- and location-specific patterns in the goat. Data may serve as a basis for future experiments on the role of VDR in Ca metabolism.

show abstract

“…Although several reports described a decrease in intestinal VDR expression (25,29), other studies showed that receptor occupancy was reduced in elder rats (43). Our findings indicate an age-related intestinal resistance to the action of 1,25(OH) 2 D 3 , which is apparently not due to a reduction in duodenal VDR mRNA levels, thereby resulting in the decline in TRPV6 expression and Ca 2ϩ absorption with aging.…”

Section: Discussionsupporting

confidence: 47%

Age-dependent alterations in Ca²⁺homeostasis: role of TRPV5 and TRPV6

Abel¹,

Huybers²,

Hoenderop³

et al. 2006

American Journal of Physiology-Renal Physiology

View full text Add to dashboard Cite

-related disorders, including hyperparathyroidism and osteoporosis. For instance, intestinal Ca 2ϩ absorption decreases with aging and, in particular, active transport of Ca 2ϩ by the duodenum (6, 14). Furthermore, there are age-related changes in renal Ca 2ϩ handling, like reduced renal tubular function and a decline in response of the kidney to PTH during aging (7,17,35,36). Renal and intestinal calbindins play an important role in active Ca 2ϩ transport, and their expression decreases with age in parallel with the age-related decline in Ca 2ϩ (re)absorption (2,6,26). In addition, the capacity of 1,25-dihydroxyvitamin D 3 to stimulate Ca 2ϩ absorption also reduces with age, whereas circulating levels of PTH rise in rats and humans (5, 12). Moreover, age-related increases in PTH levels may play an important role in bone remodeling. Bone loss occurs with aging, leading to reduced bone strength and, therefore, of osteoporotic fracture risk in the elderly (31,36,41 Ϫ/Ϫ mice exhibited significant disturbances in bone structure, including reduced trabecular and cortical bone thickness (23). These findings suggest an essential role for both TRPV5 and TRPV6 in Ca 2ϩ homeostasis. Moreover, dysfunction of these channels may contribute to disturbances in Ca 2ϩ homeostasis and have implications for age-related changes in Ca 2ϩ metabolism.

show abstract

Alterations in mRNA expression of duodenal 1,25-dihydroxyvitamin D3 receptor and vitamin D-dependent calcium binding protein in aged wistar rats

Cited by 31 publications

References 20 publications

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Immunohistochemical Demonstration of Vitamin D Receptor Distribution in Goat Intestines

Age-dependent alterations in Ca²⁺homeostasis: role of TRPV5 and TRPV6

Contact Info

Product

Resources

About

Alterations in mRNA expression of duodenal 1,25-dihydroxyvitamin D3 receptor and vitamin D-dependent calcium binding protein in aged wistar rats

Cited by 31 publications

References 20 publications

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. aries

Immunohistochemical Demonstration of Vitamin D Receptor Distribution in Goat Intestines

Age-dependent alterations in Ca2+homeostasis: role of TRPV5 and TRPV6

Contact Info

Product

Resources

About

Age-dependent alterations in Ca²⁺homeostasis: role of TRPV5 and TRPV6