Xylitol Preserves Bone in Diabetic Rats

Abstract

Dietary xylitol supplementation prevents osteoporotic changes in streptozotocin-diabetic rats.

The effects of 10% and 20% dietary xylitol supplementation on the biomechanical properties, trabeculation, and mineral content of long bones were studied in streptozotocin-diabetic rats. Forty 3-month-old male Wistar rats were divided randomly into four groups of 10. Rats in three groups were administered a single injection of streptozotocin (50 mg/kg body weight) to induce type I diabetes, while animals in the fourth group were given a sham injection of physiological saline. The sham-injected group and one of the streptozotocin-diabetic groups were fed the basal diet, while the two diabetic groups were fed the same diet supplemented with 10% and 20% xylitol (wt/wt). After 3 months, the rats were killed and the long bones were prepared for analysis. The 10% and 20% dietary xylitol supplementation significantly prevented the type I diabetes-induced decrease in the mechanical stress resistance of the tibia in the three-point bending test, the shear stress of the femur in the torsion test, and the stress resistance of the femoral neck in the loading test. No statistically significant differences were found between any groups in the values for strain or Young’s modulus in the three-point bending test, or in the values for the shear modulus of elasticity in the torsion test. These findings indicate that dietary xylitol protects against the weakening of the bone strength properties of both cortical and trabecular bone without affecting the elastic-plastic properties. Supplementation with 10% and 20% dietary xylitol significantly prevented the type I diabetes-induced decrease of humeral ash weight and tibial density. Histomorphometric data for the secondary spongiosa of the proximal tibia showed that 10% and 20% dietary xylitol supplementation also significantly prevented the type I diabetes-induced loss of trabecular bone volume. In conclusion, dietary xylitol supplementation protects against the weakening of bone biomechanical properties in streptozotocin-diabetic rats. This is related to the preserved bone mineral content and preserved trabecular bone volume.

Mattila PT, Knuuttila ML, Svanberg MJ
Metab. Clin. Exp. May 1998
PMID: 9591750

Xylitol, Sorbitol, and D-Mannitol Retard Bone Resorption in Rats

Abstract

Dietary xylitol, sorbitol and D-mannitol but not erythritol retard bone resorption in rats.

The aim of the present study was to compare the ability of four dietary polyols to reduce bone resorption. Urinary excretion of 3H radioactivity from [3H]tetracycline-prelabeled rats was used as a marker of bone resorption. After prelabeling, the rats were divided randomly into five groups of 10, and fed for 1 mo a nonpurified diet that was supplemented in four groups with either xylitol, sorbitol, D-mannitol or erythritol, respectively, to give a polyol concentration of 1 mol/kg. Xylitol (42%), sorbitol (44%) and to a lesser degree D-mannitol (23%) decreased the excretion of 3H relative to the basal diet. The erythritol group, however, did not differ from the controls. Sorbitol caused continuous diarrhea, whereas in the other groups, intestinal adaptation took place during the 1st wk of polyol feeding. In conclusion, dietary xylitol, sorbitol and to a lesser degree D-mannitol supplementations in rats retard bone resorption, whereas dietary erythritol has no effect.

Mattila PT, Svanberg MJ, Mäkinen KK, Knuuttila ML
J. Nutr. Jul 1996
PMID: 8683349 | Free Full Text

Xylitol May Help Gain Bone Calcium and Maintain Serum Citric Acid in Rats

Abstract

Citric acid concentration compared to serum parathyroid hormone, 1,25(OH)2D3 and calcitonin during dietary Ca deficiency and rehabilitation enhanced with xylitol in rats.

Young male Wistar rats were fed on a Ca-deficient diet for 3 weeks, after which dietary Ca was restored with either CaCO3 or CaCO3 + xylitol (5% per weight). Citric acid, Ca, Mg, Zn and P were determined in the tibia and femur at the beginning and after 2 and 4 weeks of rehabilitation, and serum and urinary citric acid and serum 1,25(OH)2D3, parathyroid hormone (PTH) and calcitonin were measured at the same points in time. The diminished bone Ca (p < 0.001) after 3 weeks of deficiency did not reduce the bone citric acid concentration, although serum citrate increased markedly. Simultaneously the serum 1,25(OH)2D3 concentration more than doubled and PTH increased (p < 0.01). Rehabilitation with CaCO3 + xylitol reduced the 1,25(OH)2D3 concentration to below the control level (p < 0.05), while serum citric acid remained elevated. CaCO3 alone normalized the elevated hormone and citric acid levels in the serum. Dietary CaCO3 and CaCO3 + xylitol normalized the PTH concentration equally well. The gain in bone Ca after 4 weeks of rehabilitation was significantly greater when xylitol was added compared with CaCO3 alone (p < 0.05). Only the 4-week CaCO3 + xylitol group attained the bone Ca concentration of the controls. Xylitol supplementation seems to affect the serum citric acid concentration independent of 1,25(OH)2D3 and PTH concentrations. The elevated citric acid concentration could be associated with increasing bone Ca.

Svanberg M, Knuuttila M, Hämäläinen M
Miner Electrolyte Metab 1993
PMID: 8377724

Xylitol Mainly Affects New Bone in Rats

Abstract

The effect of dietary xylitol on recalcifying and newly formed cortical long bone in rats.

Thirty-six 3-week-old male Wistar rats were labeled with a single intraperitoneal tetracycline injection. Twenty-four of them were then fed a Ca-deficient basal diet for 3 weeks, while the control group received the basal diet supplemented with CaCO3 (12 g/kg). The tetracycline labeling was then repeated and six animals in each group were decapitated. The diet of the remaining formerly Ca-deficient animals was returned to normal, and half the test rats also received xylitol supplementation (50 g/kg). After 4 weeks of rehabilitation the labeling was repeated and the animals were decapitated and their tibias were prepared. The tibias were measured in terms of weight and density and cross sections were prepared for the examination of mineral content. Bone element analysis was performed by scanning electron microscopy with electron-probe microanalysis, examining separately the bone areas formed during the various dietary periods. Areas of the former Ca-deficient and newly formed cortical bone were identified by tetracycline fluorescence under ultraviolet light, and the amount of cortical bone in each group was measured. The mineralization-promoting effect of dietary xylitol as compared with CaCO3 supplementation alone was seen more clearly in the newly formed periosteal bone than in remineralization of the formerly Ca-deficient bone, the concentrations of Ca and P being significantly elevated (P < 0.05), as also was the total mineral content (P < 0.01). The cortical bone volume was similar following the CaCO3 and CaCO3 + xylitol supplementations, suggesting unaltered formation of the organic matrix. The results show that the effect of xylitol on bone during dietary Ca rehabilitation particularly concerns newly formed bone mineral.

Svanberg M, Knuuttila M
Calcif. Tissue Int. Aug 1993
PMID: 8402322

Xylitol Improves Bioavailability of Calcium in Rats

Abstract

Bone repair in calcium-deficient rats: comparison of xylitol+calcium carbonate with calcium carbonate, calcium lactate and calcium citrate on the repletion of calcium.

The potential value of xylitol in calcium therapy was evaluated by comparing the effect of dietary xylitol (50 g/kg diet) + calcium carbonate with the effects of calcium carbonate, calcium lactate and calcium citrate on bone repair of young male rats after the rats consumed for 3 wk a calcium-deficient diet (0.2 g Ca/kg diet). After this calcium-depletion period, the rats were fed for 2 wk one of four diets, each containing 5 g Ca/kg diet as one of the four dietary calcium sources. The diet of the control animals was supplemented with CaCO3 (5 g Ca/kg diet) throughout the study. The Ca-deficient rats showed low bone mass, low serum calcium and high serum 1,25-dihydroxycholecalciferol, parathyroid hormone (1-34 fraction) and osteocalcin concentrations. They also excreted magnesium, phosphate and hydroxyproline in the urine in high concentrations, and had high bone alkaline phosphatase and tartrate-resistant acid phosphatase activities. Most of these changes were reversed by the administered of the calcium salts. The highest recoveries of femoral dry weight, calcium, magnesium and phosphate were observed in the groups receiving xylitol+CaCO3 and calcium lactate. Calcium lactate and calcium citrate caused low serum phosphate concentration compared with rats receiving CaCO3 and with the age-matched Ca-replete controls. Xylitol-treated rats excreted more calcium and magnesium in urine than did the other rats, probably due to increased absorption of these minerals from the gut. These results suggest that dietary xylitol improves the bioavailability of calcium salts.

Hämäläinen MM
J. Nutr. Jun 1994
PMID: 8207545 | Free Full Text

Xylitol Protective Against Bone Loss in Rats

Abstract

Dietary xylitol prevents ovariectomy induced changes of bone inorganic fraction in rats.

Thirty-six 3-month-old female Wistar rats were labelled with a single intraperitoneal tetracycline injection. Twenty-four animals were subsequently ovariectomized, while the control group of 12 animals underwent sham operations. All animals received the basal Ewos R3 diet and half of the ovariectomized animals (n = 12) were given an additional 5% dietary xylitol supplementation. Three months later, following the collection of blood and urine, the animals were killed by decapitation. The tibiae were detached and prepared for chemical and other studies. The weight and density of the tibiae were measured. The right tibiae were dried and pulverized for chemical analysis of calcium, phosphorus and citric acid. The total inorganic fraction was determined by ashing the powdered bone. The left tibiae were cross-sectioned at the tibio-fibular junctions for the measurement of the width of periosteally formed bone, which was identified by tetracycline fluorescence. The examination of mineral content of bone was performed by scanning electron microscopy, using an electron probe microanalytic technique. The results indicate that the supplementation of the diet with 5% xylitol had a protective effect against the loss of bone mineral after ovariectomy in the rat. This was clearly seen in tibial density and in the inorganic fraction of the bone, and in the concentrations of bone Ca and phosphorus. Ovariectomy caused a doubling in periosteal bone formation relative to the controls, whereas the growth of the periosteally formed bone was somewhat reduced following xylitol supplementation as compared with ovariectomy alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Svanberg M, Knuuttila M
Bone Miner Jul 1994
PMID: 7950507

Xylitol Reduces Bone Resorption in Rats

Abstract

Diminished bone resorption in rats after oral xylitol administration: a dose-response study.

The effects of 5, 10, and 20% dietary xylitol supplementations on the resorption of bone were studied. The resorption was measured by the urinary excretion of [3H] radioactivity from [3H]tetracycline-prelabeled rats. The 10 and 20% oral xylitol administrations caused a significant decrease in the excretion of [3H] as compared with the control group with no xylitol supplementation. The effect was detected as early as 2 days after the beginning of xylitol-feeding and was maintained throughout the experimental period of 31 days. The retarding effect on bone resorption was about 25% in the 10% xylitol group, about 40% in the 20% xylitol group, and undetectable in the 5% xylitol group. The amount of preserved [3H] radioactivity in the tibiae of the 10 and 20% xylitol groups after the experiment clearly exceeded the values of the control group. The mechanism of the retarded bone resorption caused by dietary xylitol still remains obscure, but an increased absorption of calcium may be involved. In conclusion, dietary xylitol supplementation in rats seems to retard the bone resorption in a dose-dependent way. The effect is achieved rapidly and is maintained at least over a period of 1 month xylitol feeding.

Mattila P, Svanberg M, Knuuttila M
Calcif. Tissue Int. Mar 1995
PMID: 7750030

Xylitol Improves Recalcification in Rats

Abstract

Comparison of the effect of gluconate, lactose, and xylitol on bone recalcification in calcium-deficient rats.

The therapeutic value of three calcium absorption promoting carbohydrates, lactose, gluconate and xylitol, in bone calcification was evaluated in 7-week-old male rats which were fed on a semisynthetic Ca-deficient diet for 3 weeks. Lactose + CaCO3, xylitol + CaCO3, Ca-gluconate, or CaCO3 alone were administered to the Ca-deficient rats for 2 weeks; the carbohydrate and Ca contents of the diets were 5% and 0.5%, respectively. The Ca-deficient rats showed a decrease in serum total Ca and ionized Ca2+ and in tibial Ca, Mg, P and density, with a concomitant increase in bone hydroxyproline concentration. Bone and serum tartrate-resistant acid phosphatase activities were increased 2-fold and the serum 1,25(OH)2D3 level 5-fold. Smaller increases were found in serum calcitonin, PTH, alkaline phosphatase and osteocalcin levels. These changes (except calcitonin) were reversed by the administration of Ca and the carbohydrates. It was observed that all three agents improved the recalcification of bones compared with the effect of CaCO3 alone. The effect of lactose and xylitol was superior to that of gluconate. These results suggest advantages in the use of xylitol in Ca-supplements.

Hämäläinen MM, Knuuttila M, Svanberg M, Koskinen T
Bone 1990
PMID: 2078437

Olive Oleuropein and Hydroxytyrosol Prevents Bone Loss in Mice

Abstract

Olive polyphenol hydroxytyrosol prevents bone loss.

Polyphenols reportedly exert physiological effects against diseases such as cancer, arteriosclerosis, hyperlipidemia and osteoporosis. The present study was designed to evaluate the effects of oleuropein, hydroxytyrosol and tyrosol, the major polyphenols in olives, on bone formation using cultured osteoblasts and osteoclasts, and on bone loss in ovariectomized mice. No polyphenols markedly affected the proliferation of osteoblastic MC3T3-E1 cells at concentrations up to 10μM. Oleuropein and hydroxytyrosol at 10 to 100μM had no effect on the production of type I collagen and the activity of alkaline phosphatase in MC3T3-E1 cells, but stimulated the deposition of calcium in a dose-dependent manner. In contrast, oleuropein at 10 to 100μM and hydroxytyrosol at 50 to 100μM inhibited the formation of multinucleated osteoclasts in a dose-dependent manner. Furthermore, both compounds suppressed the bone loss of trabecular bone in femurs of ovariectomized mice (6-week-old BALB/c female mice), while hydroxytyrosol attenuated H(2)O(2) levels in MC3T3-E1 cells. Our findings indicate that the olive polyphenols oleuropein and hydroxytyrosol may have critical effects on the formation and maintenance of bone, and can be used as effective remedies in the treatment of osteoporosis symptoms.

Hagiwara K, Goto T, Araki M, Miyazaki H…
Eur. J. Pharmacol. Jul 2011
PMID: 21539839

Creatine Has No Effect on Bone Mass in Hypertensive Rats

Abstract

Influence of creatine supplementation on bone mass of spontaneously hypertensive rats.

Recent evidence has suggested that creatine supplementation (Cr) can increase the bone mineral density (BMD) of the femur in healthy growing rats. Nevertheless, studies assessing the efficacy of the Cr supplementation in conditions characterized by bone mass loss are scarce.
To investigate the effect of Cr supplementation on BMD and bone mineral content (BMC) in spontaneously hypertensive rats (SHRs), an experimental model of osteoporosis.
Sixteen 8-month-old male SHRs were randomly allocated into two groups matched by body weight: 1) Pl group: SHRs treated with placebo (distilled water; n = 8); and 2) Cr group: SHRs treated with Cr (n = 8). After nine weeks of supplementation, the animals were euthanized and their femur and spine (L1-L4) were analyzed by use of densitometry (Dual Energy X-Ray Absorptiometry).
No significant difference was observed between the groups regarding either the spine or the total femur measures as follows: spine – BMD (Pl = 0.249 ± 0.003 g/cm² vs. Cr = 0.249 ± 0.004 g/cm²; P = 0.95) and BMC (Pl = 0.509 ± 0.150 g vs. Cr = 0.509 ± 0.017 g; P > 0.99); and total femur – BMD (Pl = 0.210 ± 0.004 g/cm² vs. Cr = 0.206 ± 0.004 g/cm²; P > 0.49) and BMC (Pl = 0.407 ± 0.021 g vs. Cr = 0.385 ± 0.021 g; P > 0.46).
In this study, using the experimental model of osteoporosis, Cr supplementation had no effect on bone mass.

Alves CR, Murai IH, Ramona P, Nicastro H…
Rev Bras Reumatol
PMID: 22641599 | Free Full Text