Tocotrienol supplementation in postmenopausal osteoporosis: evidence from a laboratory study

Preventative and therapeutic potential of tocotrienols on musculoskeletal diseases in ageing

Musculoskeletal health is paramount in an ageing population susceptible to conditions such as osteoporosis, arthritis and fractures. Age-related changes in bone, muscle, and joint function result in declining musculoskeletal health, reduced mobility, increased risk of falls, and persistent discomfort. Preserving musculoskeletal wellbeing is essential for maintaining independence and enhancing the overall quality of life for the elderly. The global burden of musculoskeletal disorders is significant, impacting 1.71 billion individuals worldwide, with age-related muscle atrophy being a well-established phenomenon. Tocotrienols, a unique type of vitamin E found in various sources, demonstrate exceptional antioxidant capabilities compared to tocopherols. This characteristic positions them as promising candidates for addressing musculoskeletal challenges, particularly in mitigating inflammation and oxidative stress underlying musculoskeletal disorders. This review paper comprehensively examines existing research into the preventive and therapeutic potential of tocotrienols in addressing age-related musculoskeletal issues. It sheds light on the promising role of tocotrienols in enhancing musculoskeletal health and overall wellbeing, emphasizing their significance within the broader context of age-related health concerns.

Protective Effect of Virgin Coconut Oil on Osteopenia Induced by High Refined Carbohydrate-Containing Diet in Mice

Background: Obesity leads to chronic low-grade inflammation, promoting detrimental effects on bone. The consumption of virgin coconut oil (VCO) is associated with benefits related to meta-inflammation. We evaluated the effect of VCO supplementation on osteopenia promoted by diet-induced obesity in mice. Methods: Male BALB/c mice were fed a control (C) or highly refined carbohydrate-containing (HC) diet for eight weeks. After that, the HC diet group was supplemented with three doses of VCO for four weeks. Results: The HC diet increased the adiposity and leptin levels associated with augmented systemic inflammatory cells improved with VCO supplementation. The HC diet reduced the trabecular bone in the tibia, lumbar vertebrae, distal and proximal femur, as well as the bone mineral density of the femur and alveolar bone. The VCO supplementation reverted bone osteopenia by increasing the trabecular bone in different sites and improving femur and alveolar bone microarchitecture. Although the reduced number of osteoblasts in the alveolar bone of the HC diet group was not significantly enhanced by VCO supplementation, the reduced Alp expression in the HC diet group was enhanced in the VCO group. These beneficial effects were associated with lowering the Rankl/Opg ratio. Conclusion: VCO supplementation might be an effective strategy to attenuate bone osteopenic effects induced by obesity.

γ-Tocotrienol induced the proliferation and differentiation of MC3T3-E1 cells through the stimulation of the Wnt/β-catenin signaling pathway

γ-Tocotrienol (γ-T3), an isoprenoid phytochemical, has shown the promotion of osteoblast proliferation and differentiation in our previous study. In this study, its underlying mechanism was investigated through regulating the Wnt/β-catenin signaling pathway in MC3T3-E1 cells. Comparative experiment results showed that γ-T3, not α-tocopherol (α-TOC) increased more significantly the viability and differentiation in MC3T3-E1 cells. After that, the cells were incubated with 10 mM LiCl, or 4 μM γ-T3 with or without 1 μM XAV-939. γ-T3 at 4 μM stimulated the Wnt/β-catenin signaling pathway by increasing the expression and nuclear accumulation of β-catenin, and the expressions of their downstream factors, such as cyclin-D1, c-Myc, BMP2 and BMP-4 in MC3T3-E1 cells. γ-T3 not only upregulated the viability, induced G0/G1 to the S phase, and promoted the expressions of PCNA (Proliferating Cell Nuclear Antigen) and Ki-67, but also increased ALP activity and the expressions of ON, OPN and OCN. Moreover, the effects of γ-T3 on the MC3T3-E1 cells resembled the actions of LiCl, an activator of the Wnt/β-catenin signaling pathway. Notably, all these effects of γ-T3 on the MC3T3-E1 cells were completely blocked by the Wnt/β-catenin signaling pathway inhibitor XAV-939. Our data demonstrated that γ-T3 can target β-catenin to enhance the Wnt/β-catenin signaling pathway, which led to increased expressions of the downstream cell proliferation and cell cycle-associated (cyclin D1 and c-myc), and cell differentiation-associated (BMP-2 and BMP-4) target genes, and ultimately promoted MC3T3-E1 cell proliferation and differentiation. Therefore, γ-T3 may be a potential agent to prevent and reverse osteoporosis due to its safety and powerful abilities of osteogenesis.

Normalisation of High Bone Remodelling due to Oestrogen Deficiency by Traditional Chinese Formulation Kang Shuai Lao Pian in Ovariectomised Rats

Postmenopausal osteoporosis transpires due to excessive osteoclastic bone resorption and insufficient osteoblastic bone formation in the presence of oestrogen insufficiency. Kang Shuai Lao Pian (KSLP) is a red ginseng-based traditional Chinese medicine known for its anti-ageing properties. However, studies on its effect on bone loss are lacking. Thus, the current study examined the skeletal protective effects of KSLP in an ovariectomised rodent bone loss model. Three-month-old female Sprague Dawley rats (n=42) were randomised into baseline, sham and ovariectomised (OVX) groups. The OVX rats were supplemented with low- (KSLP-L; 0.15 g/kg), medium- (KSLP-M; 0.30 g/kg), high-dose KSLP (KSLP-H; 0.45 g/kg) or calcium carbonate (1% w/v). The daily supplementation of KSLP was performed via oral gavage for eight weeks. Gavage stress was stimulated in the ovariectomised control with distilled water. The rats were euthanised at the end of the study. Whole-body and femoral bone mineral content and density scans were performed at baseline and every four weeks. Blood samples were obtained for the determination of bone remodelling markers. Histomorphometry and biomechanical strength testing were performed on femurs and tibias. High bone remodelling typically due to oestrogen deficiency, indicated by the elevated bone formation and resorption markers, osteoclast surface, single-labelled surface and mineralising surface/bone surface ratio, was observed in the untreated OVX rats. Whole-body BMD adjusted to body weight and Young's modulus decreased significantly in the untreated OVX rats. High-dose KSLP supplementation counteracted these degenerative changes. In conclusion, KSLP improves bone health by normalising bone remodelling, thereby preventing bone loss and decreased bone strength caused by oestrogen deficiency. Its anti-osteoporosis effects should be validated in patients with postmenopausal osteoporosis.

Osteoprotective Effects in Postmenopausal Osteoporosis Rat Model: Oral Tocotrienol vs. Intraosseous Injection of Tocotrienol-Poly Lactic-Co-Glycolic Acid Combination

Osteoporosis, the most common bone disease, is associated with compromised bone strength and increased risk of fracture. Previous studies have shown that oxidative stress contributes to the progression of osteoporosis. Specifically, for postmenopausal osteoporosis, the reduction in estrogen levels leads to increased oxidative stress in bone remodeling. Tocotrienol, a member of vitamin E that exhibits antioxidant activities, has shown potential as an agent for the treatment of osteoporosis. Most studies on the osteoprotective effects of tocotrienols had used the oral form of tocotrienols, despite their low bioavailability due the lack of transfer proteins and high metabolism in the liver. Several bone studies have utilized tocotrienol combined with a nanocarrier to produce a controlled release of tocotrienol particles into the system. However, the potential of delivering tocotrienol-nanocarrier combination through the intraosseous route has never been explored. In this study, tocotrienol was combined with a nanocarrier, poly lactic-co-glycolic acid (PLGA), and injected intraosseously into the bones of ovariectomized rats to produce targeted and controlled delivery of tocotrienol into the bone microenvironment. This new form of tocotrienol delivery was compared with the conventional oral delivery in terms of their effects on bone parameters. Forty Sprague-Dawley rats were divided into five groups. The first group was sham operated, while other groups were ovariectomized (OVX). Following 2 months, the right tibiae of all the rats were drilled at the metaphysis region to provide access for intraosseous injection. The estrogen group (OVX + ESTO) and tocotrienol group (OVX + TTO) were given daily oral gavages of Premarin (64.5 mg/kg) and annatto-tocotrienol (60 mg/kg), respectively. The locally administered tocotrienol group (OVX + TTL) was given a single intraosseous injection of tocotrienol-PLGA combination. After 8 weeks of treatment, both OVX + TTO and OVX + TTL groups have significantly lower bone markers and higher bone mineral content than the OVX group. In terms of bone microarchitecture, both groups demonstrated significantly higher trabecular separation and connectivity density than the OVX group (p < 0.05). Both groups also showed improvement in bone strength by the significantly higher stress, strain, stiffness, and Young's modulus parameters. In conclusion, daily oral tocotrienol and one-time intraosseous injection of tocotrienol-PLGA combination were equally effective in offering protection against ovariectomy-induced bone changes.

Changes in Bone Metabolism and Antioxidant Defense Systems in Menopause-Induced Rats Fed Bran Extract from Dark Purple Rice (Oryza sativa L. Cv. Superjami)

Menopause is a matter of concern for women’s health due to a deficiency of female hormones; additionally, reactive oxygen species and aging can cause osteoporosis. Food becomes increasingly interesting as a menopausal woman’s alternative to hormone therapy. The effects of ethanol extracts from dark purple Superjami rice bran on bone metabolism and antioxidant defense systems in menopause-induced animal models were evaluated. Female rats underwent sham surgery or were ovariectomized to induce a menopause-like state. Rats were divided into a sham control group (SHAM), an ovariectomized control group (OVX), and an ovariectomized grou supplemented with Superjami rice bran extract group (OVX-S) and fed for 8 weeks. The OVX groups exhibited significantly more weight gain, amounts of bone turnover biochemical markers (alkaline phosphatase, osteocalcin, and C-terminal telopeptide), bone loss, lipid-peroxidation and oxidative stress than the SHAM group. However, Superjami bran extract added to the diet resulted in a significant reduction in body weight and lipid peroxidation, as well as enhanced bone metabolism and antioxidant enzyme activities, in ovariectomized rats. These results propound that extracts from Superjami rice bran have therapeutic potentiality against bone loss and oxidative stress in menopause-induced states and will be useful in preventing postmenopausal osteoporosis and oxidative damage.

Potential Role of Tocotrienols on Non-Communicable Diseases: A Review of Current Evidence

Tocotrienol (T3) is a subfamily of vitamin E known for its wide array of medicinal properties. This review aimed to summarize the health benefits of T3, particularly in prevention or treatment of non-communicable diseases (NCDs), including cardiovascular, musculoskeletal, metabolic, gastric, and skin disorders, as well as cancers. Studies showed that T3 could prevent various NCDs, by suppressing 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in the mevalonate pathway, inflammatory response, oxidative stress, and alternating hormones. The efficacy of T3 in preventing/treating these NCDs is similar or greater compared to tocopherol (TF). TF may lower the efficacy of T3 because the efficacy of the combination of TF and T3 was lower than T3 alone in some studies. Data investigating the effects of T3 on osteoporosis, arthritis, and peptic ulcers in human are limited. The positive outcomes of T3 treatment obtained from the preclinical studies warrant further validation from clinical trials.

Effect of Germinated Pigmented Rice "Superjami" on the Glucose Level, Antioxidant Defense System, and Bone Metabolism in Menopausal Rat Model

Women experience physical, mental, and social changes during menopause. It is important to maintain a healthy diet for effective menopause management. The effect of germinated Superjami, a deep violet colored rice cultivar, on the body weight, glucose level, antioxidant defense system, and bone metabolism in a menopausal rat model was investigated. The animals were randomly divided into three groups and fed with a normal diet (ND), a control diet supplemented with 20% (w/w) non-germinated Superjami flour (NGSF), or germinated Superjami flour (GSF) for eight weeks. The NGSF and GSF groups exhibited significantly lower body weight and fat, glucose and insulin contents, adipokine concentrations, and bone resorption biomarker levels, and higher antioxidant enzyme activities and 17-β-estradiol content than the ND group (p < 0.05). The GSF group showed greater glucose homeostasis, antioxidative, and bone metabolism-improving effects compared with the NGSF group. These findings demonstrate that germination could further improve the health-promoting properties of Superjami and that this germinated pigmented rice cultivar could be useful in the treatment and management of menopause-induced hyperglycemia, oxidative stress, and bone turnover imbalance.

Development and characterization of supramolecular calcitonin assembly and assessment of its interactions with the bone remodelling process

Osteoporosis is the most common metabolic bone disease, which poses an immense socio-economic burden on the society. Human calcitonin, though safe, is not considered as a therapeutic option because of its high tendency to self-associate to form amyloid fibrils thereby affecting its potency. To circumvent this issue we harnessed the inherent capacity of aggregation and developed an assemblage of human calcitonin monomers, [Supramolecular Calcitonin Assembly (SCAI)], which releases biologically active calcitonin monomers in a sustained manner for a period of at least three weeks. AFM and FT-IR analysis showed that SCA-I is amorphous aggregates of calcitonin monomers. Both SCA-I and monomer released from it demonstrated superior anti-osteoclast activity and proteolytic stability in-vitro. SCA-I upon single injection significantly improved bone formation markers and reduced bone resorption markers in ovariectomized (OVX) rat model of postmenopausal osteoporosis. Micro-CT analysis revealed that calcitonin released from SCA-I exhibits its beneficial effect on cortical bone more profoundly compared to trabecular bone. This study demonstrates that SCA-I is more effective compared to the human calcitonin monomers on osteoclasts and has site-specific effect on bone in a model of post-menopausal osteoporosis. This approach opens up an innovative way to use and study the function of human calcitonin.

The Molecular Mechanism of Vitamin E as a Bone-Protecting Agent: A Review on Current Evidence

Bone remodelling is a tightly-coordinated and lifelong process of replacing old damaged bone with newly-synthesized healthy bone. In the bone remodelling cycle, bone resorption is coupled with bone formation to maintain the bone volume and microarchitecture. This process is a result of communication between bone cells (osteoclasts, osteoblasts, and osteocytes) with paracrine and endocrine regulators, such as cytokines, reactive oxygen species, growth factors, and hormones. The essential signalling pathways responsible for osteoclastic bone resorption and osteoblastic bone formation include the receptor activator of nuclear factor kappa-B (RANK)/receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG), Wnt/β-catenin, and oxidative stress signalling. The imbalance between bone formation and degradation, in favour of resorption, leads to the occurrence of osteoporosis. Intriguingly, vitamin E has been extensively reported for its anti-osteoporotic properties using various male and female animal models. Thus, understanding the underlying cellular and molecular mechanisms contributing to the skeletal action of vitamin E is vital to promote its use as a potential bone-protecting agent. This review aims to summarize the current evidence elucidating the molecular actions of vitamin E in regulating the bone remodelling cycle.

Enhancement of glucose and bone metabolism in ovariectomized rats fed with germinated pigmented rice with giant embryo (Oryza sativa L. cv. Keunnunjami)

Background

Menopause induces various metabolic disorders due to the rapid decrease of the ovarian hormone estrogen. It is involved in increased risk of obesity, diabetes, dyslipidemia, and osteoporosis. The pigmented giant embryo cultivar is a promising food product for menopause-induced metabolic disorders.

Objective

The effects of non-germinated and germinated Keunnunjami, a new blackish purple pigmented rice with a giant embryo, on glucose and bone metabolisms in ovariectomized rats were investigated.

Design

The animals were fed with normal control diet (NC group) or control diet supplemented with either non-germinated Keunnunjami (KN group) or germinated Keunnunjami (GKN group) powder for 8 weeks.

Results

The blood glucose and plasma insulin levels, adipokine concentrations, hepatic glucose-regulating enzyme activities, and bone resorption biomarker levels significantly decreased in KN and GKN groups compared to those of the control animals.

Discussion

These findings illustrate that GKN group showed greater hypoglycemic activity and lower bone resorption than KN group, suggesting that germination could further improve the physiological property of Keunnunjami.

Conclusion

Germinated Keunnunjami may have therapeutic potential against hyperglycemia and bone turnover imbalance caused by menopause.

Therapeutic effect of Vitamin E in preventing bone loss: An evidence-based review

The present review explored the anti-inflammatory and immunomodulatory properties of vitamin E, which has protective action against osteoporosis. A systematic review of the literature was conducted to identify the published bone studies on vitamin E. The studies included inflammatory or immunology-related parameters. Medline and Scopus databases were searched for relevant studies published from 2005 till 2015. Research articles published in English and confined to the effect of vitamin E on bone were included. It is pertinent to mention that these studies took into consideration inflammatory or immunology parameters including interleukin (IL)-1, IL-6, receptor activator of nuclear factor kappa-B ligand (RANKL), inducible nitric oxide synthases (iNOS), serum amyloid A (SAA), e-selection and high-sensitivity C-reactive protein (hs-CRP). An extended literature search yielded 127 potentially relevant articles with seven articles meeting the inclusion and exclusion criteria. Another recent article was added with the total number accounting to eight. All these included literature comprised five animal studies, one in-vitro study and two human studies. These studies demonstrated that vitamin E, especially tocotrienol, was able to alleviate IL-1, IL-6, RANKL, iNOS and hs-CRP levels in relation to bone metabolism. In conclusion, vitamin E exerts its anti-osteoporotic actions via its anti-inflammatory and immunomodulatory effects.

Tocotrienols for bone health: a translational approach

Osteoporosis, a degenerative bone disease, is characterized by low bone mass and microstructural deterioration of bone tissue resulting in aggravated bone fragility and susceptibility to fractures. The trend of extended life expectancy is accompanied by a rise in the prevalence of osteoporosis and concomitant complications in the elderly population. Epidemiological evidence has shown an association between vitamin E consumption and the prevention of age-related bone loss in elderly women and men. Animal studies show that ingestion of vitamin E, especially tocotrienols, may benefit bone health in terms of maintaining higher bone mineral density and improving bone microstructure and quality. The beneficial effects of tocotrienols on bone health appear to be mediated via antioxidant/anti-inflammatory pathways and/or 3-hydroxy-3-methylglutaryl coenzyme A mechanisms. We discuss (1) an overview of the prevalence and etiology of osteoporosis, (2) types of vitamin E (tocopherols versus tocotrienols), (3) findings of tocotrienols and bone health from published in vitro and animal studies, (4) possible mechanisms involved in bone protection, and (5) challenges and future direction for research.

Safety and efficacy of tocotrienol supplementation for bone health in postmenopausal women: protocol for a dose-response double-blinded placebo-controlled randomised trial

INTRODUCTION

Osteoporosis is a major health concern in postmenopausal women, and oxidative stress contributes to the development of bone loss. Cellular studies and ovariectomised rat model mimicking bone loss in postmenopausal women show the bone-protective effect of tocotrienols (TTs) with antioxidant capability. We aim to access the safety and efficacy of TT consumption for bone health in postmenopausal women.

METHODS AND ANALYSIS

In this 12-week randomised double-blinded placebo-controlled trial for the effects of dietary TT supplementation in postmenopausal women, postmenopausal women aged 45 years and older with at least 1 year after menopause and bone mineral density T-score at the spine and/or hip 2.5 or more below the reference values will be randomly assigned to 3 daily supplements: (1) placebo group receiving 860 mg olive oil, (2) low TT group receiving 430 mg of 70% pure TTs (containing 300 mg TT) and (3) high TT group receiving 860 mg of 70% pure TTs (600 mg TT). The primary outcome measure will be urinary N-terminal telopeptide. The secondary outcome measures will be serum bone-specific alkaline phosphatase, receptor activator of nuclear factor-κB ligand, osteoprotegerin, urinary 8-hydroxy-2'-deoxyguanosine and quality of life. At 0, 6 and 12 weeks, the following will be assessed: (1) primary and secondary outcome measures; (2) serum TT and tocopherol concentrations; (3) physical activity and food frequency questionnaires. Liver function will be monitored every 6 weeks for safety. 'Intent-to-treat' principle will be employed for data analysis. A model of repeated measurements with random effect error terms will be applied. Analysis of covariance, χ² analysis and regression will be used for comparisons.

ETHICS AND DISSEMINATION

This study was approved by the Bioethics Committee of the Texas Tech University Health Sciences Center. The findings of this trial will be submitted to a peer-reviewed journal in the areas of bone or nutrition and international conferences.

TRIAL REGISTRATION NUMBER

NCT02058420; results.

Germinated Pigmented Rice (Oryza Sativa L. cv. Superhongmi) Improves Glucose and Bone Metabolisms in Ovariectomized Rats

The effect of germinated Superhongmi, a reddish brown pigmented rice cultivar, on the glucose profile and bone turnover in the postmenopausal-like model of ovariectomized rats was determined. The ovariectomized Sprague-Dawley rats were randomly divided into three dietary groups (n = 10): normal control diet (NC) and normal diet supplemented with non-germinated Superhongmi (SH) or germinated Superhongmi (GSH) rice powder. After eight weeks, the SH and GSH groups showed significantly lower body weight, glucose and insulin concentrations, levels of bone resorption markers and higher glycogen and 17-β-estradiol contents than the NC group. The glucose metabolism improved through modulation of adipokine production and glucose-regulating enzyme activities. The GSH rats exhibited a greater hypoglycemic effect and lower bone resorption than SH rats. These results demonstrate that germinated Superhongmi rice may potentially be useful in the prevention and management of postmenopausal hyperglycemia and bone turnover imbalance.

Vitamin E homologues α- and γ-tocopherol are not associated with bone turnover markers or bone mineral density in peri-menopausal and post-menopausal women

In a large cohort of older women, we investigated the relationships that different forms of vitamin E may have with bone turnover markers and bone mineral density (BMD). We found a suggestive positive association between serum alpha-tocopherol and BMD at the femoral neck, but no other clinically relevant observations.

INTRODUCTION

Vitamin E has anti-oxidant and anti-inflammatory properties hypothesized to benefit bone, but limited studies exist regarding its homologues. We examined circulating and dietary α- and γ-tocopherols with bone turnover markers (BTMs) and bone mineral density (BMD), and the role of inflammation in this relationship.

METHODS

We performed two cross-sectional analyses from two visits (V2, 1997-1999, n = 3883; V3, 2007-2011, n = 2130) of the Aberdeen Prospective Osteoporosis Screening Study. Dietary and supplement intakes by food frequency questionnaire were assessed at both visits. V2 BTMs (urinary free pyridinoline and deoxypyridinoline, serum N-terminal propeptide of type 1 collagen) and V3 serum α- and γ-tocopherols, inflammatory markers (interleukin-6 [IL-6], serum amyloid A [SAA], high-sensitivity C-reactive protein [hs-CRP], E-selectin) and dual X-ray absorptiometry BMD at the femoral neck and lumbar spine were collected. Food sources of tocopherol homologues and diet-serum correlations were determined. The relationships between dietary tocopherols and BTMs (V2), and dietary and serum tocopherols with BMD (V3) were examined by multivariable regression (adjusting for age, cholesterol, inflammatory markers, carotenoids, body mass index, physical activity level, alcohol intake, smoking status and national deprivation category).

RESULTS

Serum γ-tocopherol was associated with increasing concentrations of hs-CRP, SAA and E-selectin (P-trend all <0.0001), while α-tocopherol was associated with decreasing concentrations of IL-6 and hs-CRP (P-trend all <0.001). Controlling for covariates, serum α-tocopherol was positively associated with BMD at the femoral neck (β = 0.002, P = 0.04) among those not reporting vitamin E supplementation.

CONCLUSION

We did not find biologically meaningful results between dietary and tocopherol homologues with BTMs or BMD.

Regulation of Obesity and Metabolic Complications by Gamma and Delta Tocotrienols

Tocotrienols (T3s) are a subclass of unsaturated vitamin E that have been extensively studied for their anti-proliferative, anti-oxidative and anti-inflammatory properties in numerous cancer studies. Recently, T3s have received increasing attention due to their previously unrecognized property to attenuate obesity and its associated metabolic complications. In this review, we comprehensively evaluated the recent published scientific literature about the influence of T3s on obesity, with a particular emphasis on the signaling pathways involved. T3s have been demonstrated in animal models or human subjects to reduce fat mass, body weight, plasma concentrations of free fatty acid, triglycerides and cholesterol, as well as to improve glucose and insulin tolerance. Their mechanisms of action in adipose tissue mainly include (1) modulation of fat cell adipogenesis and differentiation; (2) modulation of energy sensing; (3) induction of apoptosis in preadipocytes and (4) modulation of inflammation. Studies have also been conducted to investigate the effects of T3s on other targets, e.g., the immune system, liver, muscle, pancreas and bone. Since δT3 and γT3 are regarded as the most active isomers among T3s, their clinical relevance to reduce obesity should be investigated in human trials.

Time and dose-dependent effects of Labisia pumila on bone oxidative status of postmenopausal osteoporosis rat model

Postmenopausal osteoporosis can be associated with oxidative stress and deterioration of antioxidant enzymes. It is mainly treated with estrogen replacement therapy (ERT). Although effective, ERT may cause adverse effects such as breast cancer and pulmonary embolism. Labisia pumila var. alata (LP), a herb used traditionally for women’s health was found to protect against estrogen-deficient osteoporosis. An extensive study was conducted in a postmenopausal osteoporosis rat model using several LP doses and duration of treatments to determine if anti-oxidative mechanisms were involved in its bone protective effects. Ninety-six female Sprague-Dawley rats were randomly divided into six groups; baseline group (BL), sham-operated (Sham), ovariectomised control (OVXC), ovariectomised (OVX) and given 64.5 μg/kg of Premarin (ERT), ovariectomised and given 20 mg/kg of LP (LP20) and ovariectomised and given 100 mg/kg of LP (LP100). The groups were further subdivided to receive their respective treatments via daily oral gavages for three, six or nine weeks of treatment periods. Following euthanization, the femora were dissected out for bone oxidative measurements which include superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA) levels. Results: The SOD levels of the sham-operated and all the treatment groups were significantly higher than the OVX groups at all treatment periods. The GPx level of ERT and LP100 groups at the 9th week of treatment were significantly higher than the baseline and OVX groups. MDA level of the OVX group was significantly higher than all the other groups at weeks 6 and 9. The LP20 and LP100 groups at the 9th week of treatment had significantly lower MDA levels than the ERT group. There were no significant differences between LP20 and LP100 for all parameters. Thus, LP supplementations at both doses, which showed the best results at 9 weeks, may reduce oxidative stress which in turn may prevent bone loss via its anti-oxidative property.