Limits...
Prevention of osteoporosis by oral administration of phytate-removed and deamidated soybean β-conglycinin.

Akao M, Abe R, Sato N, Hasegawa-Tanigome A, Kumagai H, Kumagai H - Int J Mol Sci (2015)

Bottom Line: The apparent calcium absorption rate decreased following ovariectomy and was not replenished by oral administration of phytate-removed soybean β-conglycinin (PrS) or casein.Markers of bone resorption, such as serum parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD), increased, and the bone mineral density and breaking stress decreased following ovariectomy.However, PrDS supplementation suppressed the changes caused by the decrease in calcium absorption from the small intestine.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Life Science, Nihon University, 1866 Kameino, Fujisawa-shi, Kanagawa 252-0880, Japan. makao@brs.nihon-u.ac.jp.

ABSTRACT
Phytate-removed and deamidated soybean β-conglycinin (PrDS) prepared by ion-exchange resins was supplemented to be 4% in the diet administered to ovariectomized rats to investigate its preventive effect on osteoporosis. The apparent calcium absorption rate decreased following ovariectomy and was not replenished by oral administration of phytate-removed soybean β-conglycinin (PrS) or casein. On the other hand, administration of PrDS restored the calcium absorption rate to the same level as the sham group. Markers of bone resorption, such as serum parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD), increased, and the bone mineral density and breaking stress decreased following ovariectomy. However, PrDS supplementation suppressed the changes caused by the decrease in calcium absorption from the small intestine. Therefore, PrDS supplementation shows promise for the prevention of postmenopausal osteoporosis.

Show MeSH

Related in: MedlinePlus

Bone mineral density (BMD) at 4 mm from the endpoint of femurs in sham-treated and ovariectomized rats fed each experimental diet for eight weeks. (A) Cortical, (B) trabecular and (C) total BMD. Sham, non-ovariectomized and 20% egg albumin intake; control, ovariectomized and 20% egg albumin intake; PrS, ovariectomized and 4% PrS + 16% egg albumin intake; PrDS, ovariectomized and 4% PrDS + 16% egg albumin intake; casein, ovariectomized and 4% casein + 16% egg albumin intake. Values represent the means for six rats with the SE. Values indicated by different letters for the same BMD are significantly different at p < 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4307352&req=5

ijms-16-02117-f004: Bone mineral density (BMD) at 4 mm from the endpoint of femurs in sham-treated and ovariectomized rats fed each experimental diet for eight weeks. (A) Cortical, (B) trabecular and (C) total BMD. Sham, non-ovariectomized and 20% egg albumin intake; control, ovariectomized and 20% egg albumin intake; PrS, ovariectomized and 4% PrS + 16% egg albumin intake; PrDS, ovariectomized and 4% PrDS + 16% egg albumin intake; casein, ovariectomized and 4% casein + 16% egg albumin intake. Values represent the means for six rats with the SE. Values indicated by different letters for the same BMD are significantly different at p < 0.05.

Mentions: Femur bone mineral density (BMD) is shown in Figure 4. Cortical BMD (sham: 915.04 ± 1.79 mg/cm3; control: 901.17 ± 3.01 mg/cm3; PrS: 903.68 ± 1.85 mg/cm3; PrDS: 911.01 ± 2.11 mg/cm3; casein: 899.99 ± 1.98 mg/cm3) and trabecular BMD (sham: 557.63 ± 3.52 mg/cm3; control: 421.37 ± 3.65 mg/cm3; PrS: 432.28 ± 2.86 mg/cm3; PrDS: 432.17 ± 4.52 mg/cm3; casein: 431.2 ± 3.47 mg/cm3) were individually evaluated by peripheral quantitative computed tomography (pQCT) [27,28] along with total BMD (sham: 685.52 ± 6.42 mg/cm3; control: 500.19 ± 4.40 mg/cm3; PrS: 512.47 ± 3.96 mg/cm3; PrDS: 516.88 ± 4.87 mg/cm3; casein: 518.81 ± 4.03 mg/cm3). Since trabecular bone has a greater surface area than cortical bone, the remodeling rate of trabecular bone is thought to be faster than that of cortical bone [29,30], and approximately 10% of cortical bone is remodeled annually [31]. In addition, the effects of estrogen deficiency are expected to be seen first in trabecular bone [32]. Therefore, femur BMD was measured at 4 mm from the endplate where longitudinal growth occurs and trabecular bone is dominant. As expected, trabecular BMD decreased to 75.6% (=(421.37 mg/cm3)/(557.63 mg/cm3) × 100) following ovariectomy, while cortical BMD decreased only to 98.5% (=(901.17 mg/cm3)/(915.04 mg/cm3) × 100). However, a noticeable difference was observed between groups, even in cortical BMD. The cortical BMD of the PrDS group was significantly higher than that of any other ovariectomized groups and almost identical to that of the sham group (Figure 4A). The reduction occurring in trabecular BMD following ovariectomy was slightly restored in the PrS, PrDS and casein groups (Figure 4B). Because the remodeling rate of cortical bone is slow, the BMD of the PrDS group may have been retained by the suppression of bone resorption rather than by enhancement of bone formation. The cortical bone constitutes the hard outer layer and is composed of compact tissues, which account for 80% of the total bone mass. Therefore, cortical BMD affects bone strength, and the PrDS group was expected to have greater bone strength than the other ovariectomized groups.


Prevention of osteoporosis by oral administration of phytate-removed and deamidated soybean β-conglycinin.

Akao M, Abe R, Sato N, Hasegawa-Tanigome A, Kumagai H, Kumagai H - Int J Mol Sci (2015)

Bone mineral density (BMD) at 4 mm from the endpoint of femurs in sham-treated and ovariectomized rats fed each experimental diet for eight weeks. (A) Cortical, (B) trabecular and (C) total BMD. Sham, non-ovariectomized and 20% egg albumin intake; control, ovariectomized and 20% egg albumin intake; PrS, ovariectomized and 4% PrS + 16% egg albumin intake; PrDS, ovariectomized and 4% PrDS + 16% egg albumin intake; casein, ovariectomized and 4% casein + 16% egg albumin intake. Values represent the means for six rats with the SE. Values indicated by different letters for the same BMD are significantly different at p < 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4307352&req=5

ijms-16-02117-f004: Bone mineral density (BMD) at 4 mm from the endpoint of femurs in sham-treated and ovariectomized rats fed each experimental diet for eight weeks. (A) Cortical, (B) trabecular and (C) total BMD. Sham, non-ovariectomized and 20% egg albumin intake; control, ovariectomized and 20% egg albumin intake; PrS, ovariectomized and 4% PrS + 16% egg albumin intake; PrDS, ovariectomized and 4% PrDS + 16% egg albumin intake; casein, ovariectomized and 4% casein + 16% egg albumin intake. Values represent the means for six rats with the SE. Values indicated by different letters for the same BMD are significantly different at p < 0.05.
Mentions: Femur bone mineral density (BMD) is shown in Figure 4. Cortical BMD (sham: 915.04 ± 1.79 mg/cm3; control: 901.17 ± 3.01 mg/cm3; PrS: 903.68 ± 1.85 mg/cm3; PrDS: 911.01 ± 2.11 mg/cm3; casein: 899.99 ± 1.98 mg/cm3) and trabecular BMD (sham: 557.63 ± 3.52 mg/cm3; control: 421.37 ± 3.65 mg/cm3; PrS: 432.28 ± 2.86 mg/cm3; PrDS: 432.17 ± 4.52 mg/cm3; casein: 431.2 ± 3.47 mg/cm3) were individually evaluated by peripheral quantitative computed tomography (pQCT) [27,28] along with total BMD (sham: 685.52 ± 6.42 mg/cm3; control: 500.19 ± 4.40 mg/cm3; PrS: 512.47 ± 3.96 mg/cm3; PrDS: 516.88 ± 4.87 mg/cm3; casein: 518.81 ± 4.03 mg/cm3). Since trabecular bone has a greater surface area than cortical bone, the remodeling rate of trabecular bone is thought to be faster than that of cortical bone [29,30], and approximately 10% of cortical bone is remodeled annually [31]. In addition, the effects of estrogen deficiency are expected to be seen first in trabecular bone [32]. Therefore, femur BMD was measured at 4 mm from the endplate where longitudinal growth occurs and trabecular bone is dominant. As expected, trabecular BMD decreased to 75.6% (=(421.37 mg/cm3)/(557.63 mg/cm3) × 100) following ovariectomy, while cortical BMD decreased only to 98.5% (=(901.17 mg/cm3)/(915.04 mg/cm3) × 100). However, a noticeable difference was observed between groups, even in cortical BMD. The cortical BMD of the PrDS group was significantly higher than that of any other ovariectomized groups and almost identical to that of the sham group (Figure 4A). The reduction occurring in trabecular BMD following ovariectomy was slightly restored in the PrS, PrDS and casein groups (Figure 4B). Because the remodeling rate of cortical bone is slow, the BMD of the PrDS group may have been retained by the suppression of bone resorption rather than by enhancement of bone formation. The cortical bone constitutes the hard outer layer and is composed of compact tissues, which account for 80% of the total bone mass. Therefore, cortical BMD affects bone strength, and the PrDS group was expected to have greater bone strength than the other ovariectomized groups.

Bottom Line: The apparent calcium absorption rate decreased following ovariectomy and was not replenished by oral administration of phytate-removed soybean β-conglycinin (PrS) or casein.Markers of bone resorption, such as serum parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD), increased, and the bone mineral density and breaking stress decreased following ovariectomy.However, PrDS supplementation suppressed the changes caused by the decrease in calcium absorption from the small intestine.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Life Science, Nihon University, 1866 Kameino, Fujisawa-shi, Kanagawa 252-0880, Japan. makao@brs.nihon-u.ac.jp.

ABSTRACT
Phytate-removed and deamidated soybean β-conglycinin (PrDS) prepared by ion-exchange resins was supplemented to be 4% in the diet administered to ovariectomized rats to investigate its preventive effect on osteoporosis. The apparent calcium absorption rate decreased following ovariectomy and was not replenished by oral administration of phytate-removed soybean β-conglycinin (PrS) or casein. On the other hand, administration of PrDS restored the calcium absorption rate to the same level as the sham group. Markers of bone resorption, such as serum parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD), increased, and the bone mineral density and breaking stress decreased following ovariectomy. However, PrDS supplementation suppressed the changes caused by the decrease in calcium absorption from the small intestine. Therefore, PrDS supplementation shows promise for the prevention of postmenopausal osteoporosis.

Show MeSH
Related in: MedlinePlus