Pro-inflammatory effects of the aminobisphosphonate ibandronate in vitro and in vivo

Medication-associated orbital inflammation: A systematic review

We performed a comprehensive systematic review to identify medication-associated orbital inflammation and to characterize its clinico-radiological features. We reviewed English-language articles describing medication-associated orbital inflammation (i.e., orbital myositis, dacryoadenitis and orbital fat) published to June, 2023. Isolated inflammation of the intraocular structures or globe alone (i.e. uveitis, scleritis, optic neuritis and perineuritis) were excluded. In medication-associated orbital inflammation, the extraocular muscles are preferentially affected, occurring in isolation or in combination with other orbital and/or intraocular structures. Clinico-radiological manifestations may be non-specific; however, certain medications may be distinguished according to the presence of systemic prodrome, laterality, associated intraocular inflammation, and predisposition to involve certain orbital structures. Rapid identification, discontinuation of the provoking medication, and systemic corticosteroid therapy (if appropriate) typically achieves a favorable visual prognosis. As new medications become adopted by clinicians, rare adverse effects will be further delineated.Medication-associated orbital inflammation is an important diagnostic consideration in orbital inflammatory disease. A careful medication history and clinical assessment may be revealing, permitting timely discontinuation of the offending agent and initiation of appropriate management.

Association between bisphosphonate therapy and outcomes from rehabilitation in older people

BACKGROUND

Bisphosphonate therapy may have actions beyond bone, including effects on cardiovascular, immune and muscle function. We tested whether bisphosphonate treatment is associated with improved outcomes in older people undergoing inpatient rehabilitation.

METHODS

Analysis of prospectively collected, linked routine clinical datasets. Participants were divided into never users of bisphosphonates, use prior to rehabilitation only, use after rehabilitation only, and current users (use before and after rehabilitation). We calculated change in 20-point Barthel scores during rehabilitation, adjusting for comorbid disease and laboratory data using multivariable regression analysis. Cox regression analyses were performed to analyse the association between bisphosphonate use and time to death or hospitalisation.

RESULTS

2797 patients were included in the analysis. Current bisphosphonate users showed greater improvement in Barthel score during rehabilitation than non-users (5.0 points [95%CI 4.3-5.7] vs 3.8 [95%CI 3.6-3.9]), but no difference compared to those receiving bisphosphonates only after discharge (5.1 [95%CI 4.6-5.5]). Previous bisphosphonate use was significantly associated with time to death (adjusted hazard ratio 1.41 [95%CI 1.15-1.73]) but less strongly with time to combined endpoint of hospitalisation or death (adjusted hazard ratio 1.18 [95%CI 0.98-1.48]). Use after discharge from rehabilitation was associated with reduced risk of death (adjusted hazard ratio 0.64 [95%CI 0.55-0.73]; hazard ratio per year of bisphosphonate prescription 0.98 [95%CI 0.97-0.99]).

CONCLUSION

Bisphosphonate use is unlikely to be causally associated with improved physical function in older people, but continuing use may be associated with lower risk of death.

Toll-like receptor 9 expression is associated with breast cancer sensitivity to the growth inhibitory effects of bisphosphonates in vitro and in vivo

Bisphosphonates are standard treatments for bone metastases. When given in the adjuvant setting, they reduce breast cancer mortality and recurrence in bone but only among post-menopausal patients. Optimal drug use would require biomarker-based patient selection. Such biomarkers are not yet in clinical use. Based on the similarities in inflammatory responses to bisphosphonates and Toll-like receptor (TLR) agonists, we hypothesized that TLR9 expression may affect bisphosphonate responses in cells. We compared bisphosphonate effects in breast cancer cell lines with low or high TLR9 expression. We discovered that cells with decreased TLR9 expression are significantly more sensitive to the growth-inhibitory effects of bisphosphonates in vitro and in vivo. Furthermore, cancer growth-promoting effects seen with some bisphosphonates in some control shRNA cells were not detected in TLR9 shRNA cells. These differences were not associated with inhibition of Rap1A prenylation or p38 phosphorylation, which are known markers for bisphosphonate activity. However, TLR9 shRNA cells exhibited increased sensitivity to ApppI, a metabolite that accumulates in cells after bisphosphonate treatment. We conclude that decreased TLR9-expression sensitizes breast cancer cells to the growth inhibitory effects of bisphosphonates. Our results suggest that TLR9 should be studied as a potential biomarker for adjuvant bisphosphonate sensitivity among breast cancer patients.

Bisphosphonate-Induced Orbital Inflammation: A Case Series and Review

INTRODUCTION

To present a series of patients with bisphosphonate induced orbital inflammation, and to review the clinical presentation, radiological features, treatment options and outcomes.

METHODS

We present a multicentre, retrospective case series review of patients with a clinico-radiological diagnosis of bisphosphonate induced orbital inflammation and review all the reported cases of this complication in the literature.

RESULTS

Four new patients with bisphosphonate induced orbital inflammation were added to the 25 cases in the literature. Intravenous zoledronate was the commonest precipitant (22/29, 75.9%) and inflammation occurred 1-28 (mean 3) days post-infusion. Orbital imaging identified orbital inflammation in 22/29 cases and extra-ocular muscle enlargement in 8/29. Five patients presented with reduced vision of which one - with anterior ischaemic optic neuropathy - did not resolve. The vision resolved in all except one patient, with most requiring steroid treatment.

CONCLUSIONS

Bisphosphonates have a pro-inflammatory effect, which can precipitate orbital inflammation. This rare, but potentially serious complication of bisphosphonate treatment should be considered by clinicians using bisphosphonate treatment and by ophthalmologists seeing patients with orbital inflammatory disease.

Alendronate, a double-edged sword acting in the mevalonate pathway

Aminobisphosphonate aledronate is a compound commonly used clinically for the treatment of osteoporosis and other bone diseases, as a result of it preventing bone resorption. However, in previous years it has also been used to obtain cellular and animal models of a rare genetic disorder termed Mevalonate Kinase Deficiency (MKD). MKD is caused by mutations affecting the mevalonate kinase enzyme, in the cholesterol pathway and alendronate can be used to biochemically mimic the genetic defect as it inhibits farnesyl pyrophosphate synthase in the same pathway. Despite evidence in favor of the inhibition exerted on the mevalonate pathway, there is at least one clinical case of MKD in which alendronate improved not only skeletal and bone fractures, as expected, but also MKD clinical features. Based on this finding, the present study assessed the anti‑inflammatory properties of this aminobisphosphonate in vitro. No anti‑inflammatory effects of alendronate were observed in the in vitro experiments. Since MKD lacks specific treatments, these results may assist scientists and physicians in making the decision as to the most suitable choice of therapeutic compounds for this neglected disease.

Pharmacodynamics of bisphosphonates in arthritis

Inflammatory arthritis is a group of autoimmune diseases characterized by chronic inflammation of the joints. Rheumatoid arthritis, the most common form of arthritis, is associated with local joint destruction and systemic bone loss. Osteoclasts, the only cells of the body able to resorbe bone, are key players in these two types of bone loss. Bisphosphonates are analogs of pyrophosphate that inhibit osteoclast action and bone resorption. They are indicated in pathology associated with excess resorption. Besides their effect on bone they also exhibit extra-osseous properties, acting on tumor cells, inflammation and angiogenesis. As a result, they have been trialed in the context of arthritis. It is now clear that they do not have any significant direct effect on disease activity or pain. If their indication in the prevention of glucocorticoid-induced osteoporosis is clear, any beneficial effects on bone erosions are still controversial but interesting preliminary results warrant further investigations.

Bisphosphonate-associated osteonecrosis of the jaw: a key role of inflammation?

Osteonecrosis of the jaw (ONJ) can be associated with nitrogen-containing bisphosphonates (NBPs) therapy. Various mechanisms of NBP-associated ONJ have been proposed and there is currently no consensus of the underlying pathogenesis. The detailed medical and dental histories of 30 ONJ patients treated with NBPs for malignant diseases (24) or osteoporosis (6) were analyzed. The necrotic bone was resected and analyzed histologically after demineralization. In 10 patients the perinecrotic bone was also resected and processed without demineralization. Alveolar bone samples from 5 healthy patients were used as controls. In 14 ONJ patients, serial technetium-99m-methylene diphosphonate scintigraphic scans were also available and confronted to the other data. Strong radionuclide uptake was detected in some patients several months before clinical diagnosis of ONJ. The medullary spaces of the necrotic bone were filled with bacterial aggregates. In the perinecrotic bone, the bacteria-free bone marrow characteristically showed an inflammatory reaction. The number of medullary inflammatory cells taken as an index of inflammation allowed us to discriminate two inflammation grades in the ONJ samples. Low-grade inflammation, characterized by marrow fibrosis and low inflammatory cells infiltration, increased numbers of TRAP(+) mono- and multineacleated cells was seen in patients with bone exposure<2 cm(2). High-grade inflammation, associated with larger lesions, showed amounts of tartrate-resistant acid phosphatase(+)/calcitonin receptor(-) mono- and multinucleated cells, osteocyte apoptosis, hypervascularization and high inflammatory cell infiltration. The clinical extent of ONJ was statistically linked to the numbers of inflammatory cell. Taken together these data suggest that bone necrosis precedes clinical onset and is an inflammation-associated process. We hypothesize that from an initial focus, bone damage spreads centrifugally, both deeper into the jaw and towards the mucosa before the oral bone exposure and the clinical diagnosis of ONJ.

Significance and impact of bisphosphonate-induced acute phase responses

BACKGROUND

Bisphosphonates are synthetic analogs of inorganic pyrophosphates with high avidity for bone, where they bind to hydroxyapatite crystals. Bisphosphonates are effective in decreasing bone resorption, the incidence of skeletal-related events, and pain from bone metastases. These agents have recently become incorporated into the treatment regimen of patients with osteolytic and osteoblastic metastatic bone disease. Although relatively well tolerated, the initial dose(s) of intravenous aminobisphosphonates can be associated with an acute phase response, a nonspecific physiologic reaction associated with increased levels of inflammatory cytokines, fever, and flu like symptoms including fatigue, nausea, and myalgia.

OBJECTIVE

The purpose of this article is to provide an updated review of the literature in this field.

DATA SOURCE

A search of PubMed was performed using the key terms bisphosphonate, acute phase response, and cancer, and limited to publications in English. The published literature on acute phase response with bisphosphonate therapy was reviewed.

RESULTS AND CONCLUSIONS

Approximately 40% of patients receiving aminobisphosphonates experience an acute phase response, which generally occurs only on first exposure to the drug and typically last <72 h. Not all bisphosphonates induce acute phase responses to the same extent. This article reviews acute phase response in patients with metastatic bone disease treated with aminobisphosphonates.

A double-blind placebo-controlled study of intravenous clodronate for prevention of steroid-induced bone loss in inflammatory bowel disease

BACKGROUND & AIMS

Osteoporosis is common in patients with inflammatory bowel disease (IBD). Corticosteroids induce a rapid and important bone loss. Clinical trials have shown oral bisphosphonates to effectively prevent steroid-induced bone loss. However, patients with IBD have been excluded from most of these studies because of potential digestive adverse events. Clodronate is a non-amino-bisphosphonate available in intravenous form without expected digestive (as oral bisphosphonates) or proinflammatory (as amine bisphosphonates) side effects. Our aim was to assess the efficacy of intravenous clodronate in preventing steroid-induced bone loss.

METHODS

A 12-month, double-blind, randomized, placebo-controlled trial was conducted in IBD patients beginning a steroid therapy. Sixty-seven patients (median disease duration, 38 mo; range, 1-240 mo) were randomized to receive one infusion per 3 months of either intravenous clodronate (900 mg, n = 33) or placebo. All the patients received calcium (1 g/day) and vitamin D (800 IU/day). The main outcome was the change in lumbar bone mineral density (BMD) between baseline and 1 year. Secondary outcomes included change in femoral neck BMD and adverse events.

RESULTS

After 1 year, there was no change in BMD in the clodronate group, neither at the spine (-0.2%, not significant) nor at the femoral neck (2.3%, NS). In contrast, there was a significant decrease in lumbar spine (-2.0%, P = .0018) and femoral neck (-1.7%, P = .045) BMD in the placebo group. Tolerance to treatment was good.

CONCLUSIONS

Intravenous clodronate is effective in the prevention of bone loss induced by steroids in patients with IBD.

Bisphosphonate-associated arthritis

We present a case of arthritis apparently induced by the administration of intravenous bisphosphonates in a 51-year-old white woman with metastatic breast carcinoma. She presented with bilateral knee pain and effusions on 2 separate occasions after receiving aminobisphosphonates. Synovial fluid analysis was negative for infection, metastasis, or crystals. Her symptoms resolved after the medication was discontinued and recurred after the patient was rechallenged with a medication from the same drug class. The administration of aminobisphosphonates has been associated with an acute-phase response in several in vivo studies. The mechanism of action is thought to be that aminobisphosphonates transiently stimulate the production of proinflammatory cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor-alpha. Rheumatologists should be aware of this possible cause of arthropathy.

The role of human HtrA1 in arthritic disease

Human HtrA1 belongs to a widely conserved family of serine proteases involved in various aspects of protein quality control and cell fate. Although HtrA1 has been implicated in the pathology of several diseases, its precise biological functions remain to be established. Through identification of potential HtrA1 targets, studies presented herein propose that within the context of arthritis pathology HtrA1 contributes to cartilage degradation. Elevated synovial HtrA1 levels were detected in fluids obtained from rheumatoid and osteoarthritis patients, with synovial fibroblasts identified as a major source of secreted HtrA1. Mass spectrometry analysis of potential HtrA1 substrates within synovial fluids identified fibronectin as a candidate target, and treatment of fibronectin with recombinant HtrA1 led to the generation of fibronectin-degradation products that may be involved in cartilage catabolism. Consistently, treatment of synovial fibroblasts with HtrA1 or HtrA1-generated fibronectin fragments resulted in the specific induction of matrix metalloprotease 1 and matrix metalloprotease 3 expression, suggesting that HtrA1 contributes to the destruction of extracellular matrix through both direct and indirect mechanisms.

Functional characterization of a soluble gp130 isoform and its therapeutic capacity in an experimental model of inflammatory arthritis

OBJECTIVE

Soluble gp130 is the naturally occurring antagonist of the interleukin-6 (IL-6)/soluble IL-6 receptor (sIL-6R) complex and selectively inhibits IL-6 trans-signaling. Several isoforms of soluble gp130 have been identified, including an autoantigenic form termed gp130-RAPS (for gp130 of the rheumatoid arthritis antigenic peptide-bearing soluble form) that is present in the serum and synovial fluid of patients with rheumatoid arthritis. The aim of this study was to evaluate the functional properties of gp130-RAPS.

METHODS

To define a role for gp130-RAPS in arthritis, a recombinant version was generated using a baculovirus expression system, and its activities were tested in vitro and in vivo.

RESULTS

Gp130-RAPS was shown to bind with high affinity to the stable IL-6/sIL-6R complex, hyper-IL-6, and to effectively modulate leukocyte migration in murine acute peritonitis. A single intraarticular injection of gp130-RAPS suppressed chronic antigen-induced arthritis in association with a reduction in local activation of signal transducer and activator of transcription 3. Although gp130-RAPS contains the previously identified autoantigenic sequence Asn-Ile-Ala-Ser-Phe (NIASF), no increase in the prevalence of anti- gp130-RAPS antibodies was observed in serum or synovial fluid obtained from patients with rheumatoid arthritis.

CONCLUSION

The use of inhibitory antibodies to block IL-6 responses has shown considerable clinical promise. However, the results presented herein suggest that selective targeting of IL-6 trans-signaling may represent a viable alternative to this strategy. In this respect, our present results suggest that the soluble gp130 isoform gp130-RAPS may be useful in the treatment of chronic inflammatory arthritis.

Inhibition of inflammatory and bone-resorption-inhibitory effects of alendronate by etidronate

Among the bisphosphonates (BPs), the aminobisphosphonates (aminoBPs) have much stronger bone-resorption-inhibitory activities (BRIAs) than nonaminobisphosphonates (nonaminoBPs). However, aminoBPs have inflammatory effects. We previously reported that in mice: (i) all aminoBPs tested (10-40 micromol/kg) induced various inflammatory reactions (including induction of histidine decarboxylase), whereas clodronate (a non-aminoBP) (10-160 micromol/kg) inhibited these reactions; and (ii) a clear sclerotic line (tentatively called the BP line) was detectable in the tibia by radiography a few weeks after a single injection of either alendronate (a typical aminoBP) (1.6 micromol/kg) or clodronate (160 micromol/kg), and this BP-line formation (a marker for the BRIAs of BPs) was not reduced in mice given both alendronate and clodronate. In this study, using this murine model, we compared clodronate, etidronate (another typical non-aminoBP), alendronate, etidronate + alendronate, and clodronate + alendronate in terms of their inflammatory effects and/or BP-line formation. For BP-line formation, 480 micromol/kg etidronate was needed (single injection). At 160 micromol/kg, etidronate inhibited the histidine decarboxylase induction, but not the other inflammatory reactions induced by alendronate. However, etidronate (unlike clodronate) also inhibited alendronate-induced BP-line formation (even at 40 micromol/kg). Etidronate (160 micromol/kg) also inhibited the physicochemical changes in the tibia induced by six, weekly injections of alendronate. Therefore, depending on the dose, etidronate can inhibit alendronate's inflammatory actions and its BRIA. These results, together with those reported previously, suggest that a strategy utilizing clodronate (but not etidronate) plus an aminoBP might prevent or reduce the inflammatory side effects induced by aminoBPs while preserving their powerful BRIAs. We discuss the mechanisms underlying the antagonism between aminoBPs and non-aminoBPs.

Alendronate inhibits bone resorption at the bone-screw interface

In the current study, we investigated whether the systemic administration of alendronate, a third-generation bisphosphonate, suppressed the loosening of screws at the bone-screw interface. We systemically administered alendronate to rats fitted with external fixators. External fixators with two half pins were applied to the right femurs of rats, and alendronate was administrated once a week during a 5-week postoperative period. Radiographic, histologic, and immunohistochemical findings subsequently were analyzed. Treatment with alendronate reduced the width of the fibrous loosening membrane and the number of osteoclasts at the bone-screw interface. These findings indicate that systemic treatment with alendronate exerts an inhibitory effect on local bone resorption at the bone-screw interface.

Targeting osteoclasts with zoledronic acid prevents bone destruction in collagen-induced arthritis

OBJECTIVE

To study the effect of zoledronic acid (ZA) on synovial inflammation, structural joint damage, and bone metabolism in rats during the effector phase of collagen-induced arthritis (CIA).

METHODS

CIA was induced in female dark agouti rats. At the clinical onset of CIA, rats were assigned to treatment with vehicle or single subcutaneous doses of ZA (1.0, 10, 50, or 100 microg/kg). Clinical signs in all 4 paws were scored on a daily basis. After 2 weeks, the joints in the hind paws were assessed using plain radiographs, microfocal computed tomography (micro-CT), histologic scoring, and histomorphometry, and the serum levels of type I collagen crosslinks were measured by enzyme-linked immunosorbent assay.

RESULTS

Although ZA mildly exacerbated synovitis, it effectively suppressed structural joint damage. At doses of >/=10 microg/kg, ZA significantly reduced radiographic bone erosions, Larsen scores, and juxtaarticular trabecular bone loss as quantified by micro-CT. ZA prevented increased type I collagen (bone) breakdown in CIA and diminished histologic scores of focal bone erosion by up to 80%. Increases in the percentage of eroded surface, osteoclast surface, and osteoclast numbers associated with CIA were prevented by ZA, even though synovitis scores were unchanged.

CONCLUSION

Single doses (>/=10 microg/kg) of ZA strikingly reduced focal bone erosions and juxtaarticular trabecular bone loss, although synovitis was mildly exacerbated. Targeting osteoclasts with ZA may therefore be an effective strategy for preventing structural joint damage in rheumatoid arthritis.

Single infusion of neridronate (6-amino-1-hydroxyhexylidene-1,1-bisphosphonate) in patients with active rheumatoid arthritis: effects on disease activity and bone resorption markers

AIMS

The aim of this study was to assess the effects of a single infusion of the bisphosphonate neridronate (N) on parameters of inflammation and bone resorption in rheumatoid arthritis (RA).

METHODS

Forty-five patients with active RA were randomly allocated on a double blind basis to receive a single intravenous infusion of either N 25 mg (15 patients), N 50 mg (15 patients), or placebo (15 patients). At baseline and after 7 and 21 days, we assessed the following: erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and Ritchie's articular index as indices of disease activity; and urinary free deoxypyridinoline (DPyr), N-telopeptide of type I collagen (NTx) and hydroxyproline (OHP) as indices of bone resorption.

RESULTS

At day 7, N 25 mg significantly decreased ESR compared to N 50 mg (p=0.002), and CRP compared to placebo (p=0.036). With regard to bone resorption markers, at day 7, both N 25 mg and 50 mg compared to placebo significantly decreased NTx (p<0.0005 and p=0.003, respectively) and OHP (p=0.001 and p=0.004, respectively). At day 21, N 50 mg significantly decreased OHP compared to placebo (p=0.017). DPyr levels remained unchanged in the three groups.

CONCLUSIONS

N 25 mg and 50 mg exerted different effects on RA activity parameters, since only the lower dose significantly decreased ESR and CRP. Both doses of N inhibited bone resorption, with a transient, significant reduction in urinary NTx and OHP, but without any effect on DPyr.