Supplement of exogenous inorganic pyrophosphate inhibits atheromatous calcification in Apolipoprotein E knockout mice

Inorganic pyrophosphate (PPi) is the endogenous inhibitor for vascular calcification (VC). The present study was to investigate the effects of adenosine disodium triphosphate (ADTP) and alendronate sodium (AL), two exogenous PPi sources, on the atheromatous calcification (AC) in Apolipoprotein E knockout (ApoE KO) mice. ApoE KO mice were randomly divided into five groups: ApoE KO group, ApoE KO + ADTP (Low) group, ApoE KO + ADTP (High) group, ApoE KO + AL (Low) group and ApoE KO + AL (High) group. The mice in ApoE KO + ADTP (Low) group and ApoE KO + ADTP (High) group were intraperitoneally injected with ADTP with dose of 0.5 and 1.0 mg/kg/day for 2 months respectively. The mice in ApoE KO + AL (Low) group and ApoE KO + AL (High) group were intraperitoneally injected with AL with dose of 0.6 and 1.2 mg/kg/day for 2 months respectively. The age matched C57 mice were used as control group. All ApoE KO and C57 mice were fed with normal chow throughout the experiment. The calcification was evaluated using von Kossa method. The contents of PPi, triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL) and low density lipoprotein (LDL), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), interferon-γ (IFN-γ) and interleukin-10 (IL-10) as well as the activity of alkaline phosphatase (ALP) in serum were measured. The results showed that compared with C57 mice, ApoE KO mice developed severe AC accompanied with high levels of TC, TG, LDL, IL-6, TNF-α and IFN-γ in serum and with low levels of PPi and IL-10 in serum. Both ADTP and AL dose-dependently reduced the AC in ApoE KO mice compared with that of ApoE mice, without affecting the contents of lipid profiles. In addition, ADTP and AL increased the contents of PPi and IL-10 while decreased the contents of TNF-α, IL-6 and IFN-γ in serum of ApoE KO mice, having no affection on ALP activity. The results suggested that ADTP and AL reduced AC in ApoE KO mice by increasing the PPi level and regulating the inflammation.

NH2-MIL-101(Fe) nanozyme-based dual-modality sensor for determination of alendronate sodium and study of two-dimensional correlation spectroscopy

We developed a dual-modality sensing platform for ratiometric fluorescence and colorimetric determination of alendronate sodium (ALDS). This platform was performed by using a NH₂- MIL-101(Fe) as a peroxidase mimic. Since preferential complexing between Fe³⁺ (active site for peroxidase) and ALDS, the production of 2,3-diaminophenazine (DAP, oxidized product of OPD) has been inhibited in the presence of H₂O₂. As a result, the ratiometric fluorescence value of F₅₅₆/F₄₅₆ and absorbance at 450 nm exhibited significant changes, which could be used as the dual-modality sensing platform. In addition, Two-dimensional correlation spectroscopy (2D-COS) analysis on Fourier-transform infrared (FTIR), ultraviolet visible and ratiometric fluorescence spectra were applied to investigate the binding features. Synchronous and asynchronous maps of these spectra confirmed our above hypothesis, in which Fe³⁺-ALDS complex was the critical factor that regulated dual-modality signals. To our knowledge, the 2D-COS method was applied to study the catalytic and sensing mechanism of nanozyme as NH₂- MIL-101(Fe) for the first time. This technique was helpful to understand interaction of substrates on nanozyme and develop more sensitive sensors for assaying.

Effects of alendronate sodium combined with InterTan on osteoporotic femoral intertrochanteric fractures and fracture recurrence

BACKGROUND

Osteoporosis is a global disease affecting 6.6% of the total population. Osteoporosis complications include fractures, increased bone fragility, and reduced bone strength. The most commonly affected parts are the vertebral body, hip, and wrist.

AIM

To examine the effect of alendronate sodium combined with InterTan for osteoporotic femoral intertrochanteric fractures on bone and fracture recurrence

METHODS

In total, 126 cases of osteoporotic femoral intertrochanteric fractures were selected and divided into two groups according to the 1:1 principle by the simple random method. They were admitted to the Department of Orthopedics, First Affiliated Hospital of Xingtai Medical College, from January 2018 to September 2020. The control group was treated with InterTan fixation combined with placebo, and the observation group with alendronate sodium based on InterTan fixation. Operation-related indicators, complications, and recurrent fractures were compared between the groups. Changes in bone metabolism markers, t value for hip bone mineral density, and Harris Hip Score were observed.

RESULTS

Operation time, intraoperative blood loss, postoperative ambulation time, and complications were compared between the groups, and no significant difference was found. The fracture healing time was significantly shorter in the observation group than in the control group. β-Collagen-specific sequence (β-CTX) and total aminoterminal propeptide of type I procollagen (T-PINP) in the control group at 3 mo after operation were compared with those before operation, and the difference was not significant. Six months after the operation, the β-CTX level decreased and T-PINP level increased. β-CTX level at 3 and 6 mo in the observation group after operation was lower, and T-PINP level was higher, than that before operation. Compared with the control group, T-PINP level of the observation group was significantly higher and β-CTX level was significantly lower at 3 and 6 mo after operation. The t value of hip bone mineral density was compared in the control group before and 1 mo after operation, and significant difference was not found. Compared with the control group, the t value of hip bone mineral density in the observation group was significantly higher at 1, 3, 6, and 12 mo after operation. Compared with the control group, the Harris score of the observation group was significantly higher at 1, 3, 6, and 12 mo after operation. The recurrence rate of fractures in the observation group within 12 mo was 0.00%, which was significantly lower than 6.35% in the control group.

CONCLUSION

Alendronate sodium combined with InterTan in the treatment of osteoporotic femoral intertrochanteric fractures can increase bone mineral density, improve hip joint function, promote fracture healing, and reduce fracture recurrence.

Myricetin loaded nano-micelles delivery system reduces bone loss induced by ovariectomy in rats through inhibition of osteoclast formation

In recent years, much attention has been paid to the therapeutic effects of phytochemicals on osteoporosis. Other studies have shown that myricetin (MY) could promote osteogenic activity and inhibit osteoclastic effect, albeit little is known about effect of MY micellar system on osteoporosis. Therefore, we sought to discuss the therapeutic effect and mechanism of MY-loaded bone-targeting micelles on osteoporosis induced by ovariectomy (OVA) in rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles were prepared via ethanol injection method, while in vitro release study, bone targeting, pharmacokinetic studies, and the effect on proliferation of osteoblasts were investigated. Further, the therapeutic effect on osteoporosis was studied through ovariectomized rats. Compared with free MY, oral bioavailability of AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles in rats was increased by 3.54 times. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles exhibited bone targeting potential, and could significantly increase the activity of alkaline phosphatase and promote the proliferation of osteoblasts. Importantly, AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles mainly regulated bone metabolism by inhibiting bone resorption, thereby improving the symptoms of osteoporosis in OVA rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles substantially enhanced the oral bioavailability of MY and demonstrated good bone targeting capability, thereby suggesting its prospect as carrier for osteoporotic improvement in OVA rats.

Guided bone regeneration by the development of alendronate sodium loaded in-situ gel and membrane formulations

Biocompatible materials applied in guided bone regeneration are needed to prevent leakage caused by the invasion of peripheral epithelium. (2.1) The aim of this study is to develop a thermosensitive in situ gel system containing alendronate sodium loaded PLGA nanoparticles and alendronate sodium loaded membranes for guided bone regeneration. Thermosensitive Pluronic F127 gel system was preferred to prevent soft tissue migration to the defect site and prolong the residence time of the nanoparticles in this region. In situ gel system was combined with membrane formulation to enhance bone regenaration activity. Efficacy of combination system was investigated by implanting in 0.5 × 0.5 cm critical size defect in tibia of New Zealand female rabbits. According to the histopathological results, fibroblast formations were found at defect area after 6 weeks of post implantation. In contrast, treatment with the combination of in-situ gel containing nanoparticles with membrane provided woven bone formation with mature bone after 4 weeks of post implantation. As a results, the combination of in-situ gel formulation containing alendronate sodium-loaded nanoparticles with membrane formulation could be effectively applided for guided bone regeneration.

Calcifediol (25-hydroxyvitamin D) improvement and calcium-phosphate metabolism of alendronate sodium/vitamin D3 combination in Chinese women with postmenopausal osteoporosis: a post hoc efficacy analysis and safety reappraisal

BACKGROUND

Vitamin D (VD) insufficiency or deficiency is a frequent comorbidity in Chinese women with postmenopausal osteoporosis (PMO). The present study aimed to investigate 25-hydroxyvitamin D [25(OH) D] improvement and calcium-phosphate metabolism in Chinese PMO patients treated with 70 mg of alendronate sodium and 5600 IU of vitamin D₃ (ALN/D5600).

METHODS

Chinese PMO women (n = 219) were treated with 12-month ALN/D5600 (n = 111) or calcitriol (n = 108). Changes in 25(OH) D at month 12 were post hoc analyzed by the baseline 25 (OH) D status using the longitudinal analysis. The main safety outcome measures included serum calcium and phosphate and 24-h urine calcium, and the repeated measures mixed model was used to assess the frequencies of the calcium-phosphate metabolic disorders.

RESULTS

Absolute change in mean serum 25(OH) D level was the greatest in VD-deficient patients and least in VD-sufficient patients at months six and 12 (both, P < 0.01). Serum calcium level remained significantly lower in the ALN/D5600 treatment group than in the calcitriol treatment group throughout the 12 months. Mean 24-h urine calcium slightly increased in the ALN/D5600 treatment group and significantly increased in the calcitriol treatment group (+ 1.1 and + 0.9 mmol/L at months six and 12; both, P < 0.05). Calcitriol treatment was associated with more frequent hypercalciuria at month six (9.4% vs. 18.5%, P = 0.05), but not at month 12 (12.3% vs. 13.0%).

CONCLUSION

Baseline VD status predicted 25(OH) D improvement in PMO patients on 12-month ALN/D5600 treatment. The daily use of 0.25 μg of calcitriol was associated with more frequent hypercalciuria at month six, compared to ALN/5600 treatment, necessitating the safety re-evaluation of calcitriol at a higher dosage.

Tc-99m Radiolabeled Alendronate Sodium Microemulsion: Characterization and Permeability Studies Across Caco-2 Cells

BACKGROUND

Alendronate sodium (ALD) is used orally but it is poorly absorbed from the gastrointestinal (GI) tract. For this reason, microemulsion system was chosen to evaluate ALD from the GI tract after oral delivery.

OBJECTIVE

This study was aimed to prepare water-in-oil (w/o) microemulsion formulation of ALD and evaluate the permeability of ALD microemulsion from Caco-2 cell lines with radioactive and nonradioactive studies.

METHOD

The ALD microemulsion was developed by using pseudo-ternary phase diagram and composed of Soybean oil, Colliphor EL, Tween 80, Transcutol and distilled water. The prepared ALD microemulsion was characterized by physical appearance, droplet size, viscosity, pH, electrical conductivity and refractive index. The stability of the formulation was investigated for 6 months at 25±2°C/60±5% of relative humidity (RH) as well as at 40±2°C/75±5% RH. After that 1 mg of ALD was radiolabeled with 99mTc and added to microemulsion. The permeability studies were performed with both 99mTc-ALD microemulsion and ALD microemulsion.

RESULTS

The experimental results suggested that ALD microemulsion presented adequate stability with droplet size varying from 37.8±0.9 to 39.9±1.2 nm during incubation time. In addition, ALD microemulsion was radiolabeled with high labeling efficiency (>95%). In a non-radioactive study, ALD permeability was found to be 45 µg.mL-1 and microemulsion has high permeability percentage when compared to another study.

CONCLUSION

The novel w/o microemulsion formulation has been developed for oral delivery of ALD. Based on the results, permeability of ALD could be significantly improved by the microemulsion formulation. In addition, 99mTc-ALD microemulsion in capsule can be used for bone disease treatment and diagnosis.

The effect of alendronate sodium on trabecular bone structure in an osteoporotic rat model

Objectives

TObjectives: This study aims to investigate the effect of alendronate sodium on trabecular bone structure in an osteoporotic rat model.

Materials and methods

Between May 2006 and July 2006, 60 female Wistar Albino rats aged three months were randomly allocated to three groups: sham operated receiving no treatment (Shm); ovariectomized-alendronate receiving 1 mg/kg/day alendronate sodium (Ovx-A), and ovariectomized-vehicle receiving 1 mL/kg/day physiological saline (Ovx-PS). Both Ovx groups received treatment through gastric gavage for 56 days.

Results

Densitometric measurements showed that bone mineral density decreased in the Ovx-PS and increased in Ovx-A groups (p<0.05). Biomechanical measurements showed a decrease in the breaking force in the Ovx-PS group and an increase in the Ovx-A group (p<0.05). Histomorphometric measurements showed that the Shm group had normal trabecular structure, while the Ovx-PS group had a less well- formed trabecular structure with a loss in the trabecular number and thickness and a corresponding increase in the trabecular spacing (p<0.05). In the Ovx-A group, there was an improvement in the trabecular structure with an increase in the trabecular number and thickness and a loss in the trabecular space (p<0.05).

Conclusion

Our study results suggest that alendronate sodium is a valuable treatment agent for osteoporosis in postmenopausal women.

Determination of pKa values of alendronate sodium in aqueous solution by piecewise linear regression based on acid-base potentiometric titration

As a mono-sodium salt form of alendronic acid, alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups. The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and pH value based on acid-base potentiometric titration reaction. The distribution curves of alendronate sodium were drawn according to the determined pKa values. There were 4 dissociation constants (pKa₁=2.43, pKa₂=7.55, pKa₃=10.80, pKa₄=11.99, respectively) of alendronate sodium, and 12 existing forms, of which 4 could be ignored, existing in different pH environments.

Effect of alendronate sodium on tooth movement in ovariectomized rats

OBJECTIVES

The aim of the present study was to evaluate the effect of two different dosages of alendronate on induced orthodontic movement in an experimental model involving rats with osteoporosis following ovariectomy.

DESIGN

Female Wistar rats (Rattus norvegicus) eight weeks of age were divided into four groups (n=12/group): ovariectomized (OVX group); ovariectomized and treated with alendronate sodium at 1mg/kg (Group OVX+ALN1); ovariectomized and treated with alendronate sodium at 2mg/kg (Group OVX+ALN2); and sham operated (control). Three months after ovariectomy, the maxillary right first molar was submitted to movement for five and seven days. After the death of the animals, the maxilla were removed and processed for microscopic evaluation. The maxillary left first molar (without movement) was used for comparison purposes in all groups. The samples were processed for the quantification of alveolar bone and tooth movement.

RESULTS

Intragroup comparisons showed significant movement after five and seven days (p<0.05) for all groups. Comparison among groups revealed greater tooth movement in the OVX group (p<0.05), on day 7.

CONCLUSIONS

Both alendronate sodium doses similarly decreased tooth movement in ovariectomized rats (p>0.05). Movement in ovariectomized+alendronate groups were also smaller than non-ovariectomized rats, however without statistical difference.

In vivo lung deposition and sub-acute inhalation toxicity studies of nano-sized alendronate sodium as an antidote for inhaled toxic substances in Sprague Dawley rats

INTRODUCTION

Alendronate sodium is a bisphosphonate agent used for the treatment of osteoporosis and other bone diseases. It has a strong chelating property to bind or, to some extent, counteract the effects of substances, such as magnesium, calcium citrate, ferrous fumarate, carbonyl iron, as well as the zinc gluconate, sulfate and acetate salts. The objective of the present study was to evaluate lung deposition and sub-acute inhalation toxicity of the alendronate sodium respiratory formulation.

METHODS

Particle dimension of aerosols of alendronate was measured using a particle size analyzer. Alendronate was radiolabeled using Technetium-99m for in vitro and in vivo biodistribution studies. Alendronate at doses, 0.5%, 1.0%, and 1.5% in ethanol-saline respiratory formulation was inhaled twice a day up to 5 weeks for inhalation toxicity investigations. Hematological, biochemical and lung toxicity biomarkers in bronchoalveolar lavage (BAL) fluid were determined at the end of the experiment. Histopathological analysis of lung tissues was carried out to observe any microscopic changes

RESULTS

Particle size analysis revealed the size within 300-500nm. Anderson cascade impactor results showed that the particles exhibited higher respirable fraction (55.52%) with MMAD of 4.66μm. Hematology, serum biochemistry and lung toxicity biomarkers in BAL fluid performed in the sub-acute toxicity studies indicated no adverse effects of alendronate sodium inhalation except for a significant increase in cholesterol levels and marginal increase in BAL fluid protein. At autopsy, no histopathological changes in major organs were observed.

CONCLUSIONS

The lung deposition and safety evaluation data observed from these studies suggested that aerosolized nanosized alendronate sodium by the inhalation route could be a new and promising route of administration as an antidote to radioactive substances through an increase in the bioavailability of the drug as well as a decrease in side effects on systemic delivery.

Mass spectrometry and molecular modeling studies on the inclusion complexes between alendronate and β-cyclodextrin

Complexation of alendronate sodium (AlnNa) with β-cyclodextrin (β-CD) was studied by means of ESI-mass spectrometry. The experimental results show that stable 1:1 inclusion complexes between selected bisphosphonates and β-CD were formed. In addition, complexes with different stoichiometry were observed. DFT/B3LYP calculations were performed to elucidate the different inclusion behavior between alendronate and β-CD. Molecular modeling showed that the inclusion complex of Aln-β-CD where the two phosphonate groups bound to the central carbon atom of bisphosphonate were inserted into the cavity of β-CD from its “top” side was thermodynamically more favorable than when they were inserted from its “bottom” side; the complexation energy was −74.05 versus −60.85 kcal/mol. The calculations indicated that the formation of conventional hydrogen bonds was the main factor for non-covalent β-CD:Aln complex formation and stabilization in the gas phase.

Alendronate-induced esophagitis in an elderly woman

Ingestion of alendronate sodium (Fosamax) had been reported to sometimes cause erosive or ulcerative esophagitis. Despite its widespread use and several case reports describing the clinical and endoscopic presentation, there has been limited discussion on the histologic appearances of the esophagitis caused by the medication. Here we describe one case of an elderly woman who presented with alendronate-induced esophagitis. The histopathologic changes that make this case unique are the large, "bizarre" squamous epithelial cells and scattered dyskaratotic cells, two findings not well described in previous reports. These unique features add to the histologic spectrum of alendronate-induced esophageal injury, and shall help differentiating this type of esophagitis from those with other etiologies.