Category Archives: Resveratrol

Resveratrol Preserves Bone Mass, Structure, and Strength in Inactive Rats

Abstract

Resveratrol supplementation preserves long bone mass, microstructure, and strength in hindlimb-suspended old male rats.

Resveratrol has gained popularity as an “anti-aging” compound due to its antioxidant and anti-inflammatory properties. Few studies have investigated the role of resveratrol supplementation in the prevention of age-related bone loss and skeletal disuse despite increased inactivity and age-related bone loss in the elderly. The objective of the study was to investigate the effect of resveratrol supplementation on disuse and age-related bone loss. Old (age 33 months) Fischer 344 × Brown Norway male rats were provided either trans-resveratrol (12.5 mg/kg bw/day) or deionized distilled water by oral gavage for 21 days. Rats were hindlimb-suspended (HLS) or kept ambulatory (AMB) for 14 days. Both femora and tibiae were collected. Bone mass was measured by dual-energy X-ray absorptiometry and bone microstructure was determined by micro-computed tomography. HLS of old male rats accelerated loss of bone mineral content, decreased trabecular bone volume per unit of total volume, and increased trabecular separation. Resveratrol supplementation ameliorated bone demineralization and loss of bone microarchitecture in HLS old male rats. The peak force measured by the three-point bending test was reduced (P = 0.007) in HLS/control compared to AMB/control rats. Resveratrol supplementation ameliorated HLS-induced loss of femur strength. Plasma osteocalcin and alkaline phosphatase was higher (P < 0.04) and C-reactive protein was lower (P = 0.04) in old male rats given resveratrol. The bone protective effects of resveratrol appeared to be mediated through increased osteoblast bone formation, possibly due to reduced inflammation. Based on the results, resveratrol supplementation appeared to provide a feasible dietary therapy for preserving the skeletal system during disuse and age-related bone loss.

Durbin SM, Jackson JR, Ryan MJ, Gigliotti JC…
J. Bone Miner. Metab. May 2013
PMID: 23686002

Review: Resveratrol Osteogenic Effects In Vitro

Abstract

Osteogenic effects of resveratrol in vitro: potential for the prevention and treatment of osteoporosis.

There are a number of pharmacological agents for the treatment of bone mineral loss and osteoporosis. Hormone replacement therapy (HRT) with estrogen is an established treatment, but it has several adverse side effects and can increase the risk of cancer, heart disease, and stroke. There is increasing interest in nutritional factors and naturally occurring phytochemical compounds with the potential for preventing age-related and postmenopausal bone loss. Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a polyphenolic phytoestrogen with osteogenic and osteoinductive properties. It can modify the metabolism of bone cells and has the capacity to modulate bone turnover. This paper provides an overview of current research on resveratrol and its effects on bone cells in vitro, highlighting the challenges and opportunities facing this area of research, especially in the context of providing nutritional support for postmenopausal women who may not benefit from HRT and older patients with various forms of arthritis, metabolic bone disease, and osteoporosis.

Mobasheri A, Shakibaei M
Ann. N. Y. Acad. Sci. Jul 2013
PMID: 23855466

8-Prenylnaringenin > Genistein for Preventing Osteoporosis in Ovariectomized Rats; Resveratrol Has no Effect

Abstract

Comparison of the phytohormones genistein, resveratrol and 8-prenylnaringenin as agents for preventing osteoporosis.

As the average age of society increases, identifying and preventing osteoporosis becomes more important. According to the results of the Women’s Health Initiative study, substitution of estradiol is not recommended in hormone replacement therapy (HRT), although phytoestrogens might be a safe alternative. In this study, the osteoprotective effects of genistein (Gen), resveratrol (Res) and 8-prenylnaringenin (8PN) were evaluated by analysing bone biomechanical strength and bone mineral density. After ovariectomy, 88 female rats received soy-free food (C), and according to their grouping, were fed estradiol (E), GEN, RES or 8PN for 12 weeks. The phytohormones were given in two dosages. To analyse the osteoprotective effects of the tested substances, bone biomechanical properties and bone mineral density (BMD) were evaluated on the upper tibial metaphysis. Bone biomechanical properties were significantly improved after treatment with E (F (max): 90.6 N) and 8PN (85.0 N) compared to GEN (76.0 N), RES (72.6 N) and C (76.6 N). Bone biomechanical properties with 8PN (yL: 55.7 N) supplementation reached a level similar to that seen after E (49.3 N) supplementation. Treatment with GEN (38.5 N) was not as effective as E and 8PN, but demonstrated improved biomechanical properties compared to C (40.1 N) and RES (36.3 N). E (Cn.Dn. 217 mg/cm (3)) and 8PN (165 mg/cm3) showed superior results in the analysis of bone mineral density compared to C (112 mg/cm (3)). GEN (164 mg/cm (3)) also demonstrated superior results, though not as good as E and 8PN. RES (124 mg/cm (3)) revealed no effect on bone density. Treatment with 8PN resulted in very good biomechanical properties and showed an increased BMD. GEN had a smaller effect on bone biomechanical strength, while RES did not have an effect on bone biomechanical strength or BMD. Therefore, 8PN might be a safe alternative for HRT, but further studies are needed.

Sehmisch S, Hammer F, Christoffel J, Seidlova-Wuttke D…
Planta Med. Jun 2008
PMID: 18537073

It is surprising and disappointing that resveratrol had no effect on bone density in this study.

Resveratrol Prevents Bone Loss in Inactive Rats

Abstract

Effect of prior treatment with resveratrol on density and structure of rat long bones under tail-suspension.

Physical inactivity during space flight or prolonged bed rest causes rapid and marked loss of bone mass in humans. Resveratrol, a red wine polyphenol that is currently under study for its therapeutic antioxidant properties, has been shown to significantly modulate biomarkers of bone metabolism, i.e., to promote osteoblast differentiation and to prevent bone loss induced by estrogen deficiency. However, there is no direct evidence supporting its inhibitory effect toward bone loss during physical inactivity. In the present study, effects of resveratrol on bone mineral density (BMD), bone mineral content, and bone structure were examined in the femora and tibiae of tail-suspended and unsuspended rats using X-ray micro-computed tomography (micro-CT). Rats were treated with 400 mg/kg/day of resveratrol for 45 days and half of them were suspended during the last 2 weeks of treatment. Suspension caused a decrease in tibial and femoral BMD and deterioration of trabecular and cortical bone. Bone deterioration during suspension was paralleled by increased bone marrow area, which could be caused by an increase in stromal cells with osteoclastogenic potential or in adipocytes. Resveratrol had a preventive effect against bone loss induced by hindlimb immobilization. In particular, trabecular bone in the proximal tibial metaphysis was totally preserved in rats treated with resveratrol before tail-suspension.

Habold C, Momken I, Ouadi A, Bekaert V…
J. Bone Miner. Metab. Jan 2011
PMID: 20458604

Review: Resveratrol + Genistein + Quercetin + Vitamin D Synergy

Abstract

Synergism between resveratrol and other phytochemicals: implications for obesity and osteoporosis.

Resveratrol, a phytoalexin, has gained much attention recently due to its effects on sirtuins. While the anti-cancer properties of resveratrol have been extensively investigated, the anti-adipogenic and osteogenic effects of resveratrol are also gaining considerable interest. The finding that resveratrol supplementation mimics caloric restriction prompted researchers to study the effects of resveratrol on lipid metabolism. Mesenchymal stem cells are the precursors for both adipocytes and osteoblasts. In the aging population, differentiation to adipocytes dominates over the differentiation to osteoblasts in bone marrow, contributing to the increased tendency for fractures to occur in the elderly. Thus, an inverse relationship exists between adipocytes and osteoblasts in the bone marrow. Resveratrol acts on several molecular targets in adipocytes and osteoblasts leading to a decrease in adipocyte number and size and an increase in osteogenesis. Furthermore, resveratrol in combination with genistein and quercetin synergistically decreased adipogenesis in murine and human adipocytes. A recent in vivo study showed that phytochemicals including resveratrol in combination with vitamin D prevented weight gain and bone loss in a postmenopausal rat model. Therefore, combinations of resveratrol with other phytochemicals may lead to potential novel potent therapies for both obesity and osteoporosis.

Rayalam S, Della-Fera MA, Baile CA
Mol Nutr Food Res Aug 2011
PMID: 21538845

Resveratrol Stimulates Osteocalcin in Rat Cells

Abstract

Estradiol and resveratrol stimulating effect on osteocalcin, but not osteonectin and collagen-1alpha gene expression in primary culture of rat calvarial osteoblast-like cells.

Evidence is available that some endocrine disruptors, acting as selective estrogen receptor modulators (SERMs), interfere with osteoblast differentiation and function. Therefore, we investigated whether 17beta-estradiol, bisphenol-A (BSP), silymarin, genistein, resveratrol, procymidone, linurone and benzophenone-3 (BP3) modulate differentiation of rat calvarial osteoblast-like (ROB) cells in primary in vitro culture. Disruptors were added at day 18 of culture and cells were harvested 48 h later. Real time-PCR revealed that estradiol and resveratrol enhanced osteocalcin mRNA expression in ROB cells, while other disruptors were ineffective. The expression of osteonectin and collagen-1alpha was not affected by any disruptor. Estradiol, resveratrol, genistein and BSP stimulated the proliferative activity of ROB cells. In contrast, procymidone and linurone inhibited the proliferative activity, and silymarin and BP3 were ineffective. The conclusion is drawn that i) only resveratrol is able, like estradiol, to stimulate the specialized functions of ROB cells, and ii) the proliferative activity of ROB cells is more sensitive to endocrine disruptors, some of which could probably act via a mechanism independent of their SERM activity.

Rucinski M, Ziolkowska A, Hochol A, Pucher A…
Int. J. Mol. Med. Oct 2006
PMID: 16964405

Vitamin D + Genistein + Quercetin + Resveratrol in Ovariectomized Rats

Abstract

Preventing bone loss and weight gain with combinations of vitamin D and phytochemicals.

Vitamin D and certain natural compounds have been shown to regulate both lipid metabolism and bone formation. Treatments that prevent or reverse age-related increase in bone marrow adiposity could both increase new bone formation and inhibit bone destruction. We tested the hypothesis that dietary supplementation with combinations of vitamin D and phytochemicals inhibits bone loss and decreases adiposity to a greater extent than control or vitamin D-alone diets. Aged ovariectomized female rats (12 months old, n=50, initial body weight=240 g) were given control (AIN-93M diet), vitamin D (2,400 IU/kg), or vitamin D plus resveratrol (16, 80, or 400 mg/kg of diet [low, medium, and high dose, respectively]), quercetin (80, 400, or 2,000 mg/kg of diet), and genistein (64, 256, or 1,040 mg/kg of diet) for 8 weeks. The high-dose treatment (vitamin D+400 mg/kg resveratrol+2,000 mg/kg quercetin+1,040 mg/kg genistein) reduced body weight gain (P<.05) and the fat pad weights (P<.05). This treatment also increased the serum concentration of insulin-like growth factor-1 (P<.05) and the bone mineral content of the femur. Micro-computed tomography and histomorphometric analyses indicated that the high-dose treatment prevented loss of trabecular bone (P<.05) and reduced marrow adipocytes (P<.001) and osteoclasts (P<.05) compared with the control and vitamin D alone (P<.05). We conclude that aged ovariectomized female rats supplemented with vitamin D combined with genistein, quercetin, and resveratrol had improved bone mineral density and reduced body weight gain and a significant decrease in bone marrow adipocytes. The synergistic effects of a combination of phytochemicals with vitamin D may be effective in reducing bone loss and weight gain after menopause.

Lai CY, Yang JY, Rayalam S, Della-Fera MA…
J Med Food Nov 2011
PMID: 21663481

AMPK Activators: Lipoic Acid, Metformin, EGCG, Berberine, Resveratrol Can Inhibit Bone Resorption in Mice

Abstract

AMP kinase acts as a negative regulator of RANKL in the differentiation of osteoclasts.

AMP-activated protein kinase (AMPK) has been reported to stimulate differentiation and proliferation of osteoblasts, but the role of AMPK in the physiology of osteoclasts has not been investigated.
Osteoclasts were differentiated from mouse BMMϕs. TRAP-positive multinucleated cells were considered to be osteoclasts using TRAP staining, and resorption area was determined by incubation of cells on dentine discs. Signaling pathways were investigated using Western blotting and RT-PCR.
RANKL induced phosphorylation/activation of AMPK-α in BMMϕs and stimulated formation of TRAP-positive multinucleated cells. Pharmacological inhibition of AMPK with compound C and siRNA-mediated knockdown of AMPK-α1, the predominant α-subunit isoform in BMMϕs, increased RANKL-induced formation of TRAP-positive multinucleated cells and bone resorption via activation of the downstream signaling elements p38, JNK, NF-κB, Akt, CREB, c-Fos, and NFATc1. STO-609, an inhibitor of CaMKK, completely blocked the RANKL-induced activation of AMPK-α, but KN-93, an inhibitor of CaMK, did not. siRNA-mediated TAK1 knockdown also blocked RANKL-induced activation of AMPK-α. The AMPK activators metformin, (-)-epigallocatechin-3-gallate, berberine, resveratrol, and α-lipoic acid dose-dependently suppressed formation of TRAP-positive multinucleated cells and bone resorption.
AMPK negatively regulates RANKL, possibly by acting through CaMKK and TAK1. Thus, the development of AMPK activators may be a useful strategy for inhibiting the resorption of bone that is stimulated under RANKL-activated conditions.

Lee YS, Kim YS, Lee SY, Kim GH…
Bone Nov 2010
PMID: 20696287

Review: Fruits and Phytochemicals

Abstract

Fruits and dietary phytochemicals in bone protection.

Osteoporosis is a disease of bone characterized by loss of bone matrix and deterioration of bone microstructure that leads to an increased risk of fracture. Cross-sectional studies have shown a positive association between higher fruit intake and higher bone mineral density. In this review, we evaluated animal and cellular studies of dried plum and citrus and berry fruits and bioactive compounds including lycopene, phenolics, favonoids, resveratrol, phloridzin, and pectin derived from tomato, grapes, apples, and citrus fruits. In addition, human studies of dried plum and lycopene were reviewed. Animal studies strongly suggest that commonly consumed antioxidant-rich fruits have a pronounced effect on bone, as shown by higher bone mass, trabecular bone volume, number, and thickness, and lower trabecular separation through enhancing bone formation and suppressing bone resorption, resulting in greater bone strength. Such osteoprotective effects seem to be mediated via antioxidant or anti-inflammatory pathways and their downstream signaling mechanisms, leading to osteoblast mineralization and osteoclast inactivation. In future studies, randomized controlled trials are warranted to extend the bone-protective activity of fruits and their bioactive compounds. Mechanistic studies are needed to differentiate the roles of phytochemicals and other constitutes in bone protection offered by the fruits. Advanced imaging technology will determine the effective doses of phytochemicals and their metabolites in improving bone mass, microarchitecture integrity, and bone strength, which is a critical step in translating the benefits of fruit consumption on osteoporosis into clinical data.

Shen CL, von Bergen V, Chyu MC, Jenkins MR…
Nutr Res Dec 2012
PMID: 23244535