Black tea may be a prospective adjunct for calcium supplementation to prevent early menopausal bone loss in a rat model of osteoporosis

Nutraceuticals and Functional Foods: A Comprehensive Review of Their Role in Bone Health

Bone health is the result of a tightly regulated balance between bone modeling and bone remodeling, and alterations of these processes have been observed in several diseases both in adult and pediatric populations. The imbalance in bone remodeling can ultimately lead to osteoporosis, which is most often associated with aging, but contributing factors can already act during the developmental age, when over a third of bone mass is accumulated. The maintenance of an adequate bone mass is influenced by genetic and environmental factors, such as physical activity and diet, and particularly by an adequate intake of calcium and vitamin D. In addition, it has been claimed that the integration of specific nutraceuticals such as resveratrol, anthocyanins, isoflavones, lycopene, curcumin, lutein, and β-carotene and the intake of bioactive compounds from the diet such as honey, tea, dried plums, blueberry, and olive oil can be efficient strategies for bone loss prevention. Nutraceuticals and functional foods are largely used to provide medical or health benefits, but there is an urge to determine which products have adequate clinical evidence and a strong safety profile. The aim of this review is to explore the scientific and clinical evidence of the positive role of nutraceuticals and functional food in bone health, focusing both on molecular mechanisms and on real-world studies.

Protective Effects of Black Tea (<i>Camellia sinensis</i>) Extract on Endosulfan Induced Oxidative Stress, Inflammation and Hepatic Damage in Rats

With the agricultural expansion the use of pesticides is increasing rapidly in developing countries. Endosulfan, an organochlorine insecticide, is a broadspectrum effective compound used in wide variety of agricultural crops but known to generate free radicals in the liver and caused hepatotoxicity. Thus, we considered it necessary to explore the protective effect of black tea extract against endusulfan mediated hepatotoxicity. 18 male albino Wistar rats were divided into 3 groups: Control, endosulfan treated (5mg/kg body weight/day) and endosulfan+black tea extract treated (1ml of 2.5gm%/100gm of body weight/day). After 30 days of treatment period, all the animals were sacrificed, and blood and liver tissue were collected. Serum and tissue cholesterol, serum liver function parameters, liver oxidative stress parameters and serum proinflammatory cytokines were measured. Liver sections were stained with haematoxylene and eosine and histological evaluation was done. Results revealed that endusulfan induces oxidative stress in liver by altering oxidant/antioxidant balance, and causes inflammation resulting into hepatic damage. Black tea extract supplementation shows considerable protection against endosulfan mediated changes in liver. Thus, black tea extract exerts ameliorative effect against endosulfan mediated liver toxicity.

Protective effect of rhaponticin on ovariectomy-induced osteoporosis in rats

Rhaponticin is a constituent isolated from numerous medicinal herbs. It has been reported earlier that rhaponticin possesses numerous biological effects like antiallergic, antidiabetic, hepatoprotective, and antithrombosis. The goal of this exploration was to scrutinize the therapeutic potential of rhaponticin on ovariectomy (OVX)-triggered osteoporosis in rats. Female Sprague Dawley rats were arbitrarily allocated to a sham-operated control group I, group II, which underwent OVX, and groups III and IV that underwent OVX were administered with rhaponticin (10 and 20 mg/kg). Rhaponticin was supplemented orally after 4 weeks of OVX and continued for about 16 weeks. Our findings exhibit that rhaponticin prevented the BMD diminution of femurs, induced by OVX, and protected the worsening of trabecular microarchitecture that are assisted through a noteworthy decline in skeletal remodeling as noticed through the diminished status of bone markers in a dose-dependent manner (10 and 20 mg/kg). OVX rats treated with rhaponticin efficiently enhanced body weight, lipid profiles, uterine index, bone turnover markers, inflammatory markers, and augmented the incidence of calcium in the OVX rats. Rhaponticin was established to restrain the functions of acid phosphatase, estradiol, and bone gla protein in OVX rats. Also, rhaponticin displayed some beneficial effects on histomorphometric and histopathological examination. It was observed that tabular area and thickness were reinstated in sham control and rhaponticin-treated OVX rats. We recognized that rhaponticin did not induce a damaging outcome on the skeletal organization of OVX rats. Moreover, we denote that rhaponticin can be an exceptional agent for the treatment and deal with associated bone diseases.

Chitosan-gold nanoparticles mediated gene delivery of c-myb facilitates osseointegration of dental implants in ovariectomized rat

Osseointegration of dental implants is affected by osteoporosis. The purpose of this study was overcome the implant failure and facilitate the osseointegration of dental implants by c-myb in ovariectomized (OVX)-induced osteoporosis. c-myb is a transcription factor and supports bone formation. Plasmid DNA/c-myb conjugated with chitosan-gold nanoparticles (Ch-GNPs/c-myb) promoted osteogenesis and inhibited osteoclastogenesis in MC-3T3 E1 cells. Ch-GNPs/c-myb involved the reduction of the nuclear factor of activated T-cells 1, c-Fos, and tartrate-resistant acid phosphatase-positive multinucleated osteoclasts in receptor activator of nuclear factor-κB ligand (RANKL) stimulated bone marrow macrophages. In vivo results of rat mandibles demonstrated Ch-GNP/c-myb-coated titanium (Ti) implants increased the volume and density of newly formed bone and the osseointegration of dental implant with bone by micro computed tomography examination after OVX-induced osteoporosis. Immunohistochemical analysis showed increased c-myb expression and upregulation of bone morphogenic proteins, osteoprotegerin and EphB4, as well as the downregulation of RANKL by Ch-GNP/c-myb-coated Ti implants. Hematoxylin and Eosin staining expressed new bone formation by Ch-GNP/c-myb-coated Ti implants. Our findings indicated that c-myb delivered by Ch-GNPs supports osseointegration of dental implant even in osteoporotic condition. c-myb may be applicable to support dental implant integration and treatment in age-dependent bone destruction disease.

Bone health consequence of adjuvant Anastrozole in monotherapy or associated with biochanin-A in ovariectomized rat model

AIMS

We investigate the consequence of adjuvant anastrozole (ANA) in monotherapy or associated with biochanin A (BCA) in ovariectomized (OVX) rat model and the degree of developing bone loss in both conditions.

MATERIALS AND METHODS

Sixty female rats were assigned to six groups. Five groups were bilaterally OVX, and one was sham operated. The five groups were; ANA group (0.5 mg/kg b.wt orally), BCA (5 mg/kg b.wt intraperitoneally (I/P), co-treated group (BCA + ANA), two control groups receiving even distilled water orally or DMSO I/P for twenty weeks. Bone turnover biomarkers BALP, OC, PTH, TRAP and TNFα were determined in serum. Bone mineral content, histological and morphometric measurements on rat femurs were performed. BMD by X-ray technique on tibias of rats and CT analysis of lumbar vertebrae of all treated and sham groups were applied.

KEY FINDINGS

There was marked elevation in bone turnover biomarkers with high serum Ca and P content in the ANA-treated rats. Moreover marked elevation of TNFα, PTH, TC and TG, ANA caused severe changes in the BMD detected by X-ray in tibial bones and CT analysis of lumbar vertebrae of OVX rats. While I/P injection of BCA ameliorated the adverse bone health decrements caused by ANA.

SIGNIFICANCE

The study highlights the importance of the BCA supplementation in accordance with the ANA therapy in case of ovariectomized rat model of osteoporosis which is clinically presented in Postmenopausal women with breast cancer during which considerable risk of developing osteoporosis is predicted during treatment.

Effect of Black Tea Extract and Thearubigins on Osteoporosis in Rats and Osteoclast Formation in vitro

Background: Osteoporosis is a major health problem that is closely related to substantial morbidity, mortality and decline in life quality for the aging population. Although previous studies and epidemiological evidence have demonstrated an association between black tea consumption and the prevention of bone loss, the underlying mechanism remains unclear. So, the effect of black tea extract (BTE) and thearubigins (TRs) on osteoporosis in rats and osteoclast formation in vitro were investigated.

Methods:In vivo, ovariectomized (OVX) rats were used to establish osteoporosis models. To validate the model and study the effects of BTE and TRs on osteoporosis, the female Wistar rats were divided into a sham-operated group and five OVX groups including model, Xian-Ling-Gu-Bao (XLGB) (as a positive control), BTE, TRs low-dose, and TRs high-dose group. The rats in the four treatment groups were given the corresponding test sample for 12 weeks. Then, the body weight, femur indices, and serum biomarkers were examined and analyzed. In vitro, RAW264.7 murine macrophages were used as model of osteoclast formation. The effects of BTE and TRs on osteoclasts formation and the specific genes and protein levels of osteoclasts were determined.

Results: Although there was no significant effect on the OVX-induced body weight gain by BTE or TRs, the levels of maximum bending force, cortical bone thickness and biomarker of bone resorption (acid phosphatase) can be significantly ameliorated by BTE or TRs in OVX rats. Furthermore, both of BTE and TRs can inhibit the osteoclastogenesis and diminish the expression levels of the related genes and proteins.

Pu-erh Tea Extract Ameliorates Ovariectomy-Induced Osteoporosis in Rats and Suppresses Osteoclastogenesis In Vitro

Background and Objective: Tea drinking is associated with positive effects on bone health and may protect against osteoporosis, especially in elderly women. Pu-erh tea has many beneficial effects on human health; however, whether Pu-erh tea has anti-osteoporotic potential remains unclear. Thus, we investigated the effects of Pu-erh tea extract (PTE) on ovariectomy-induced osteoporosis in rats and on osteoclastogenesis in vitro.

Methods: Female Wistar rats were divided into six groups: the sham, model, and Xian-Ling-Gu-Bao capsule (XLGB) groups, and the low-, medium-, and high-dose PTE groups. Ovariectomized (OVX) rats were used as an animal model of osteoporosis. The animals were intragastrically administered distilled water, XLGB, or different concentrations of PTE for 13 weeks. Body weight, blood biochemical indicators, relative organ coefficients, femoral bone mineral density (BMD), bone biomechanical properties, and bone microarchitecture were examined and analyzed. Additionally, the in vitro effects of PTE on osteoclastic activities were investigated using the RAW 264.7 cell line as an osteoclast differentiation model. The effects of PTE on osteoclast differentiation and the expression of osteoclast-specific genes and proteins were determined.

Results: PTE reduced OVX-induced body weight gain after 6 weeks of treatment, and the high-dose exerted a significant effect. High-dose PTE significantly ameliorated OVX-induced estradiol (E₂) deficiency. PTE treatment maintained calcium and phosphorus homeostasis and improved other blood biochemical parameters to various degrees. In addition, PTE treatment improved organ coefficients of the femur, uterus, and vagina and improved femoral BMD and bone biomechanical properties. PTE treatment strikingly ameliorated bone microarchitecture. Moreover, in the in vitro studies, osteoclast differentiation using the differentiation cell model was significantly inhibited by PTE without cytotoxic effects. Additionally, PTE efficaciously suppressed the expression of key osteoclast-specific genes and proteins.

Conclusion: PTE can ameliorate ovariectomy-induced osteoporosis in rats and suppress osteoclastogenesis in vitro.

Natural Phenol Polymers: Recent Advances in Food and Health Applications

Natural phenol polymers are widely represented in nature and include a variety of classes including tannins and lignins as the most prominent. Largely consumed foods are rich sources of phenol polymers, notably black foods traditionally used in East Asia, but other non-edible, easily accessible sources, e.g., seaweeds and wood, have been considered with increasing interest together with waste materials from agro-based industries, primarily grape pomace and other byproducts of fruit and coffee processing. Not in all cases were the main structural components of these materials identified because of their highly heterogeneous nature. The great beneficial effects of natural phenol-based polymers on human health and their potential in improving the quality of food were largely explored, and this review critically addresses the most interesting and innovative reports in the field of nutrition and biomedicine that have appeared in the last five years. Several in vivo human and animal trials supported the proposed use of these materials as food supplements and for amelioration of the health and production of livestock. Biocompatible and stable functional polymers prepared by peroxidase-catalyzed polymerization of natural phenols, as well as natural phenol polymers were exploited as conventional and green plastic additives in smart packaging and food-spoilage prevention applications. The potential of natural phenol polymers in regenerative biomedicine as additives of biomaterials to promote growth and differentiation of osteoblasts is also discussed.

Noni leaf and black tea enhance bone regeneration in estrogen-deficient rats

OBJECTIVE

Black tea and Nonileaf are among the dietary compounds that can benefit patients with bone resorption disorders. Their bone regeneration effects and their mechanisms were studied in estrogen-deficient rats.

METHODS

Noni leaves (three doses) and black tea water extracts were fed to ovariectomized rats for 4 mo, and their effects (analyzed via mechanical measurements, micro-computed tomography scan, and reverse transcriptase polymerase chain reaction mRNA) were compared with Remifemin (a commercial phytoestrogen product from black cohosh).

RESULTS

The water extracts (dose-dependently for noni leaves) increased bone regeneration biomarker (runt-related transcription factor 2, bone morphogenetic protein 2, osteoprotegerin, estrogen receptor 1 [ESR1], collagen type I alpha 1A) expressions and reduced the inflammatory biomarkers (interleukin-6, tumor necrosis factor-α, nuclear factor [NF]-κB, and receptor activator of NF-κB ligand) mRNA expressions/levels in the rats. The extracts also improved bone physical and mechanical properties. The extracts demonstrated bone regeneration through improving bone size and structure, bone mechanical properties (strength and flexibility), and bone mineralization and density.

CONCLUSIONS

The catechin-rich extract favored bone regeneration and suppressed bone resorption. The mechanisms involved enhancing osteoblast generation and survival, inhibiting osteoclast growth and activities, suppressing inflammation, improving bone collagen synthesis and upregulating ESR1 expression to augment phytoestrogenic effects. Estrogen deficiency bone loss and all extracts studied (best effect from Morinda leaf at 300 mg/kg body weight) mitigated the loss, indicating benefits for the aged and menopausal women.

Tea flavonoids for bone health: from animals to humans

Osteoporosis is a skeletal disease characterized by a deterioration of bone mass and bone quality that predisposes an individual to a higher risk of fragility fractures. Emerging evidence has shown that the risk for low bone mass and osteoporosis-related fractures can be reduced by nutritional approaches aiming to improve bone microstructure, bone mineral density, and strength. Tea and its flavonoids, especially those of black tea and green tea, have been suggested to protect against bone loss and to reduce risk of fracture, due to tea's antioxidant and anti-inflammatory properties. Based on the results of animal studies, moderate intake of tea has shown to benefit bone health as shown by mitigation of bone loss and microstructural deterioration as well as improvement of bone strength and quality. Epidemiological studies have reported positive, insignificant, and negative impacts on bone mineral density at multiple skeletal sites and risk of fracture in humans with habitual tea consumption. There are limited human clinical trials that objectively and quantitatively assessed tea consumption and bone efficacy using validated outcome measures in a population at high risk for osteoporosis, along with safety monitoring approach. This review summarizes the current state of knowledge of laboratory animal research, epidemiological observational studies, and clinical trials assessing the skeletal effects of tea and its active flavonoids, along with discussion of relevant future directions in translational research.

Dietary and pharmacological compounds altering intestinal calcium absorption in humans and animals

The intestine is the only gate for the entry of Ca to the body in humans and mammals. The entrance of Ca occurs via paracellular and intracellular pathways. All steps of the latter pathway are regulated by calcitriol and by other hormones. Dietary and pharmacological compounds also modulate the intestinal Ca absorption process. Among them, dietary Ca and P are known to alter the lipid and protein composition of the brush-border and basolateral membranes and, consequently, Ca transport. Ca intakes are below the requirements recommended by health professionals in most countries, triggering important health problems. Chronic low Ca intake has been related to illness conditions such as osteoporosis, hypertension, renal lithiasis and incidences of human cancer. Carbohydrates, mainly lactose, and prebiotics have been described as positive modulators of intestinal Ca absorption. Apparently, high meat proteins increase intestinal Ca absorption while the effect of dietary lipids remains unclear. Pharmacological compounds such as menadione, dl-butionine-S,R-sulfoximine and ursodeoxycholic acid also modify intestinal Ca absorption as a consequence of altering the redox state of the epithelial cells. The paracellular pathway of intestinal Ca absorption is poorly known and is under present study in some laboratories. Another field that needs to be explored more intensively is the influence of the gene × diet interaction on intestinal Ca absorption. Health professionals should be aware of this knowledge in order to develop nutritional or medical strategies to stimulate the efficiency of intestinal Ca absorption and to prevent diseases.

[Fundamental study on effect of high-mineral drinking water for osteogenesis in calciprivia ovariectomized rats]

Since osteoporosis is a major public health problem in Japan, it is important to clarify the effect of high-mineral drinking water consumption on osteogenesis. Therefore, in this study, we investigated the relationship between high-mineral drinking water consumption and osteogenesis in ovariectomized rats that received a low-calcium diet and purified water (PW group) or a low-calcium diet and high-mineral drinking water (CR group). High-mineral drinking water affected the rats' body weight. After 3 months, the bone density of the CR group was higher than that of the PW group (p<0.05). Furthermore, the CR group showed a decrease in the amount of calcium in the bones after 3 months. These results suggest that high-mineral drinking water contributes to the maintenance of bone density and not to the amount of calcium in bone. On the other hand, serum alkaline phosphatase levels in the PW group at 3 months were higher than those in the CR group, which indicates that the blood concentration of calcium in the CR group was maintained. Moreover, the amount of magnesium in the bones and the blood concentration of magnesium in the CR group after 3 months were higher than the corresponding values in the PW group. These results suggest that consumption of high-mineral drinking water could be beneficial for osteogenesis (i.e., for maintaining bone quantity).