Pentoxifylline and Tocopherol in the Management of Temporal Bone Osteoradionecrosis: A Case Series

Benjamin D Lovin, Jonathan S Choi, Nathan R Lindquist, Jack Phan, Paul W Gidley, Marc-Elie Nader

Otol Neurotol . 2020 Jul 27. doi: 10.1097/MAO.0000000000002781. Online ahead of print.

Abstract

Objective: Temporal bone osteoradionecrosis (TBORN) is a rare, chronic complication of head and neck radiation. Initial treatment consists of conservative management, with surgical resection of necrotic bone indicated for cases of severe, symptomatic, or progressive disease. Pentoxifylline-tocopherol (PENTO) has demonstrated usefulness for osteoradionecrosis of other head and neck subsites. Herein, we report five TBORN cases utilizing this protocol.

Study design: Retrospective case series.

Setting: Tertiary referral center.

Patients: This case series describes five TBORN cases in which the PENTO protocol was used in conjunction with conservative management. All patients were women and average age was 61 ± 8 years.

Intervention: All patients received a daily dose of 800 mg of pentoxifylline and 1 g of tocopherol. Four of the five patients received systemic and/or ototopical antibiotics as an antimicrobial regimen before and/or during the PENTO protocol.

Main outcome measures: Details regarding the total duration of protocol, improvement in symptoms, exposed bone and radiographic changes, and duration until first improvement of exposed bone were collected retrospectively.

Results: The average duration of PENTO protocol was 302 ± 166 days. Four of the five (80%) patients demonstrated a decrease in exposed ear canal bone. Three of the five (60%) patients had stable or improvement in otologic symptoms of TBORN. One patient progressed to diffuse TBORN. The average duration until first improvement in exposed bone was 193 ± 137 days.

Conclusions: The PENTO protocol may be a useful adjunct to conservative measures in the management of localized TBORN. We recommend trialing the protocol for at least 12 months.

Mariya O Pitel, Erica C McKenzie, Jennifer L Johns, Robert L Stuart

J Vet Intern Med . 2020 Jul 20. doi: 10.1111/jvim.15862. Online ahead of print.

Abstract

Background: Selenium or alpha-tocopherol deficiency can cause neuromuscular disease. Beta-carotene has limited documentation in horses.

Objective: To evaluate the effect of owner practices on plasma beta-carotene concentration and risk of selenium and alpha-tocopherol deficiencies.

Animals: Three-hundred and forty-nine adult (≥1 year), university and privately owned horses and mules.

Methods: Cross-sectional study. Whole blood selenium, plasma alpha-tocopherol, and plasma beta-carotene concentrations were measured once. Estimates of daily selenium and vitamin E intake, pasture access, and exercise load were determined by owner questionnaire. Data were analyzed using t tests, Mann-Whitney tests, parametric or nonparametric analysis of variance (ANOVA), Kruskal-Wallis test, Spearman’s correlation and contingency tables (P < .05).

Results: Nearly 88% of the horses received supplemental selenium; 71.3% received ≥1 mg/d. Low blood selenium concentration (<80 ng/mL) was identified in 3.3% of horses, and 13.6% had marginal concentrations (80-159 ng/mL). Non-supplemented horses were much more likely to have low blood selenium (odds ratio [OR], 20.2; 95% confidence interval [CI], 9.26-42.7; P < .001). Supplemental vitamin E was provided to 87.3% of horses; 57.7% received ≥500 IU/d. Deficient (<1.5 μg/mL) and marginal (1.5-2.0 μg/mL) plasma (alpha-tocopherol) occurred in 15.4% and 19.9% of horses, respectively. Pasture access (>6 h/d) and daily provision of ≥500 IU of vitamin E was associated (P < .001) with higher plasma alpha-tocopherol concentrations. Plasma beta-carotene concentration was higher in horses with pasture access (0.26 ± 0.43 versus 0.12 ± 0.13 μg/mL, P = .003).

Conclusions and clinical importance: Suboptimal blood selenium and plasma alpha-tocopherol concentrations occurred in 16.7% and 35.5% of horses, respectively, despite most owners providing supplementation. Inadequate pasture access was associated with alpha-tocopherol deficiency, and reliance on selenium-containing salt blocks was associated with selenium deficiency.

Kok-Yong Chin, Benjamin Ka Seng Thong, Rhivaldy Faahim Kamalulloh, Nur Vaizura Mohamad, Sok Kuan Wong, Azlan Mohd Arlamsyah, Rahma Triliana, Ima Nirwana Soelaiman

Drug Des Devel Ther . 2020 Jul 2;14:2561-2572. doi: 10.2147/DDDT.S260565. eCollection 2020.

Abstract

Purpose: Prolonged use of proton pump inhibitors may cause bone loss, and limited therapeutic agents are available to prevent this skeletal side effect. The combination of annatto tocotrienol, a bone anabolic agent, with calcium presents a novel strategy to prevent bone loss caused by proton pump inhibitors. This study aims to compare the effects of calcium alone and in combination with annatto tocotrienol or vitamin D₃ (Caltrate Plus) in preventing bone loss caused by pantoprazole.

Methods: Three-month-old Sprague Dawley male rats (n=30) were randomised into five groups (n=6/group). Bone loss was induced by pantoprazole (3 mg/kg p.o.) in four groups, and they were treated concurrently with either calcium carbonate (77 mg p.o.), calcium carbonate (77 mg p.o.) plus annatto tocotrienol (60 mg/kg p.o.) or Caltrate Plus (31 mg p.o.) for 60 days. The rats were euthanised at the end of the experiment, and their femurs were harvested for X-ray micro-computed tomography, bone cellular histomorphometry and bone mechanical strength analysis.

Results: Pantoprazole caused significant deterioration of trabecular bone microstructures but did not affect other skeletal indices. Calcium supplementation with or without annatto tocotrienol prevented the deterioration of trabecular microstructures at the femur but did not improve other skeletal indices. Annatto tocotrienol did not enhance the skeletal actions of calcium, whereas Caltrate Plus did not affect the bone health indices in these rats.

Conclusion: Calcium supplementation per se can prevent the deterioration of bone trabecular microstructures in rats receiving long-term treatment of pantoprazole.

Lina M Escobar, Zita Bendahan, Andrea Bayona, Jaime E Castellanos, María-Clara González

Int J Dent . 2020 Jul 1;2020:8860840. doi: 10.1155/2020/8860840. eCollection 2020.

Abstract

Introduction: The aim of the present study was to determine the effects of vitamins D and E on the proliferation, morphology, and differentiation of human dental pulp stem cells (hDPSCs).

Methods: In this in vitro experimental study, hDPSCs were isolated, characterized, and treated with vitamins D and E, individually and in combination, utilizing different doses and treatment periods. Changes in morphology and cell proliferation were evaluated using light microscopy and the resazurin assay, respectively. Osteoblast differentiation was evaluated with alizarin red S staining and expression of RUNX2, Osterix, and Osteocalcin genes using real-time RT-PCR.

Results: Compared with untreated cells, the number of cells significantly reduced following treatment with vitamin D (49%), vitamin E (35%), and vitamins D + E (61%) after 144 h. Compared with cell cultures treated with individual vitamins, cells treated with vitamins D + E demonstrated decreased cell confluence, with more extensive and flatter cytoplasm that initiated the formation of a significantly large number of calcified nodules after 7 days of treatment. After 14 days, treatment with vitamins D, E, and D + E increased the transcription of RUNX2, Osterix, and Osteocalcin genes.

Conclusions: Vitamins D and E induced osteoblastic differentiation of hDPSCs, as evidenced by the decrease in cell proliferation, morphological changes, and the formation of calcified nodules, increasing the expression of differentiation genes. Concurrent treatment with vitamins D + E induces a synergistic effect in differentiation toward an osteoblastic lineage.

Lavinia Casati, Francesca Pagani, Roberto Maggi, Francesco Ferrucci, Valeria Sibilia

Int J Mol Sci . 2020 Jun 30;21(13):4661. doi: 10.3390/ijms21134661.

Abstract

Bone remodeling and repair require osteogenic cells to reach the sites that need to be rebuilt, indicating that stimulation of osteoblast migration could be a promising osteoanabolic strategy. We showed that purified δ-tocotrienol (δ-TT, 10 μg/mL), isolated from commercial palm oil (Elaeis guineensis) fraction, stimulates the migration of both MC3T3-E1 osteoblast-like cells and primary human bone marrow mesenchymal stem cells (BMSC) as detected by wound healing assay or Boyden chamber assay respectively. The ability of δ-TT to promote MC3T3-E1 cells migration is dependent on Akt phosphorylation detected by Western blotting and involves Wnt/β-catenin signalling pathway activation. In fact, δ-TT increased β-catenin transcriptional activity, measured using a Nano luciferase assay and pretreatment with procaine (2 µM), an inhibitor of the Wnt/β-catenin signalling pathway, reducing the wound healing activity of δ-TT on MC3T3-E1 cells. Moreover, δ-TT treatment increased the expression of β-catenin specific target genes, such as Osteocalcin and Bone Morphogenetic Protein-2, involved in osteoblast differentiation and migration, and increased alkaline phosphatase and collagen content, osteoblast differentiation markers. The ability of δ-TT to enhance the recruitment of BMSC, and to promote MC3T3-E1 differentiation and migratory behavior, indicates that δ-TT could be considered a promising natural anabolic compound.

Harsh V Gupta, Steven Swank, Vibhash D Sharma

Ann Indian Acad Neurol . May-Jun 2020;23(3):372-374. doi: 10.4103/aian.AIAN_29_20.

A 43-year-old right-handed man was seen in the clinic for an evaluation of progressive gait difficulty. He initially developed tingling in his hands and feet at the age of 30 years. After 3 years of initial symptoms, he developed weakness in his lower distal extremities. His symptoms progressed over the years and he developed unsteady gait, double vision, speech changes, and tremor in his right hand and head. He also complained of diarrhea (five to six loose watery bowel movements a day) and required frequent emergency evaluations for the management of the same. He was found to have colonic dilatation (11.4 cm). His past medical history was significant for jejunal resection at the time of birth. There was no family history of similar neurological problems.

Kyoung-Woon Kim, Bo-Mi Kim, Ji-Yeon Won, Hong Ki Min, Seoung Joon Lee, Sang-Heon Lee, Hae-Rim Kim

Korean J Intern Med . 2020 Jun 19. doi: 10.3904/kjim.2019.372. Online ahead of print.

Abstract

Background/aims: The present study aimed to investigate whether tocotrienol regulates interleukin 17 (IL-17)-induced osteoclastogenesis in rheumatoid arthritis (RA).

Methods: We evaluated the effect of tocotrienol on IL-17-induced receptor activator of nuclear factor kappa B ligand (RANKL) production using RA fibroblast-like synoviocyte (FLS), together with real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Osteoclast differentiation was confirmed after culturing IL-17-treated RA FLS and Th17 cells with tocotrienol and monocytes. We analyzed the suppressive effect of tocotrienol on Th17 cells percentage or Th17-cytokine levels among peripheral blood mononuclear cells using flow cytometry.

Results: We found that IL-17 stimulated FLS to produce RANKL and tocotrienol decreased this IL-17-induced RANKL production. Tocotrienol decreased the IL-17-induced activation of mammalian target of rapamycin, extracellular signal-regulated kinase, and inhibitor of kappa B-alpha. When monocytes were incubated with IL-17, RANKL, IL-17-treated FLS or Th17 cells, osteoclasts were differentiated and tocotrienol decreased this osteoclast differentiation. Tocotrienol reduced Th17 cell differentiation and the production of IL-17 and sRANKL; however, tocotrienol did not affect Treg cell differentiation.

Conclusions: Tocotrienol inhibited IL-17- activated RANKL production in RA FLS and IL-17-activated osteoclast formation. In addition, tocotrienol reduced Th17 differentiation. Therefore, tocotrienol could be a new therapeutic choice to treat bone destructive processes in RA.

Elisa Balboa, Fujiko Saavedra, Luis A Cea, Valeria Ramírez, Rosalba Escamilla, Aníbal A Vargas, Tomás Regueira, Juan C Sáez

Int J Mol Sci . 2020 Jun 8;21(11):E4094. doi: 10.3390/ijms21114094.

Abstract

Glucocorticoids are frequently used as anti-inflammatory and immunosuppressive agents. However, high doses and/or prolonged use induce undesired secondary effects such as muscular atrophy. Recently, de novo expression of connexin43 and connexin45 hemichannels (Cx43 HCs and Cx45 HCs, respectively) has been proposed to play a critical role in the mechanism underlying myofiber atrophy induced by dexamethasone (Dex: a synthetic glucocorticoid), but their involvement in specific muscle changes promoted by Dex remains poorly understood. Moreover, treatments that could prevent the undesired effects of glucocorticoids on skeletal muscles remain unknown. In the present work, a 7-day Dex treatment in adult mice was found to induce weight loss and skeletal muscle changes including expression of functional Cx43/Cx45 HCs, elevated atrogin immunoreactivity, atrophy, oxidative stress and mitochondrial dysfunction. All these undesired effects were absent in muscles of mice simultaneously treated with Dex and vitamin E (VitE). Moreover, VitE was found to rapidly inhibit the activity of Cx HCs in freshly isolated myofibers of Dex treated mice. Exposure to alkaline pH induced free radical generation only in HeLa cells expressing Cx43 or Cx45 where Ca²⁺ was present in the extracellular milieu, response that was prevented by VitE. Besides, VitE and two other anti-oxidant compounds, Tempol and Resveratrol, were found to inhibit Cx43 HCs in HeLa cells transfectants. Thus, we propose that in addition to their intrinsic anti-oxidant potency, some antioxidants could be used to reduce expression and/or opening of Cx HCs and consequently reduce the undesired effect of glucocorticoids on skeletal muscles.

Mulliez MA, Schilling C, Grupp TM

Biomed Res Int. 2020 Mar 23;2020:2568428. doi: 10.1155/2020/2568428. eCollection 2020.

Abstract

Previous studies have shown that increased cross-link density, reduced free radicals, and increased antioxidant grafting resulting from electron-beam irradiation at elevated temperatures improved the wear performance and the oxidative stability of vitamin E blended UHMWPE. The current study explores the impact of elevated irradiation temperature on vitamin E blended UHMWPE using X-ray. We hypothesize that the effects of temperature would be similar to those observed after electron-beam irradiation due to the relatively high dose rate of X-rays. Two X-ray doses of 80 and 100 kGy and two irradiation temperatures, that is, room temperature and 100°C were considered. The reference was Vitelene®, a vitamin E stabilized polyethylene cross-linked with 80 kGy by e-beam at 100°C. Oxidation index and oxidation induction time, as well as cross-link density, gel fraction, and trans-vinylene index, were determined, as the oxidative and network properties are decisive for the long-term implant performance. Gel fraction and oxidation induction time were significantly improved subsequently to warm irradiation in comparison with the material irradiated at room temperature. In conclusion, X-ray irradiation at elevated temperatures resulted in an increase of cross-linking and oxidative resistance of vitamin E stabilized polyethylene comparable to those of e-beam irradiated UHMWPE.

Veen L, Hantikainen E, Bellocco R, Ye W, Serafini M, Ponzano M, Grotta A, Trolle Lagerros Y

Eur J Nutr. 2020 Apr 2. doi: 10.1007/s00394-020-02239-8. [Epub ahead of print]

Abstract

PURPOSE:

Oxidative stress might play an important role in the development of osteoarthritis, but not much is known about the effect of antioxidants on osteoarthritis risk. We, therefore, aimed to investigate the effect of dietary vitamin C, E, beta-carotene, and non-enzymatic antioxidant capacity (NEAC), which measures overall antioxidant activity from the diet, on the risk of osteoarthritis.

METHODS:

For this study 43,865 men and women from the Swedish National March Cohort (SNMC) were followed for up to 19 years. We computed dietary intake of vitamin C, E and beta-carotene using information from a Food Frequency Questionnaire (FFQ). To estimate dietary NEAC we combined the information from the FFQ with food item-specific antioxidant capacity values from an antioxidant food database. Cases of osteoarthritis were identified through the Swedish National Patient Registers. We categorized all exposure variables into sex-specific quartiles and used multivariable-adjusted Cox proportional hazards regression models to estimate hazard ratios (HRs) with 95% confidence intervals (95% CIs).

RESULTS:

In total, we observed 5976 cases of OA during 469,148 person-years of follow-up. After adjusting for potential confounders, we did not find any association between vitamin C, beta-carotene and NEAC (p-values for trend > 0.5), but a positive association was found with higher dietary vitamin E intake (HR Q4 vs Q1: 1.11; 95% CI 1.02-1.21; p for trend = 0.01) and the risk of OA.

CONCLUSION:

Our findings do not provide evidence for dietary antioxidants to protect from the development of OA, and a higher dietary vitamin E intake might even increase the risk.