Nonsteroidal anti-inflammatory drugs and corticosteroids for the management of canine osteoarthritis

Use of Bedinvetmab (Librela®) for Canine Osteoarthritis in France, Germany, Italy, Spain, and the UK: Quantitative Analysis of Veterinarian Satisfaction and Real-World Treatment Patterns

Bedinvetmab (Librela®) represents a new class of canine osteoarthritis pain therapy. The aim of this study was to understand patient selection, usage behaviours, and satisfaction amongst veterinarians using bedinvetmab. Overall, 1932 patient record forms (PRF) were collected from 375 veterinarians across five countries in Europe. Veterinarians were asked to provide 5-7 PRF representing an average patient prescribed bedinvetmab. Veterinarian satisfaction with bedinvetmab usage averaged 8.0 out of 10.0 across all countries. Dissatisfaction as a reason for discontinuation was less than 1% for veterinarians. Veterinarians prescribed bedinvetmab broadly, across patient severity stages, weights, and ages. Adherence to monthly dosing per the product label was over 99%, and compliance with bedinvetmab treatment regimens was 85%. Following initiation of bedinvetmab, the proportion of patients requiring multiple pharmacological therapies for osteoarthritis pain fell from 47% to 31% (p < 0.05). After initiation of bedinvetmab, the mean total number of pharmacological therapies per patient across the population was 1.3, a reduction from 1.9 pre-treatment (p < 0.05). This investigation provides evidence on the benefit of bedinvetmab use post-launch in a broad population of dogs across the five most populous countries in western Europe. Compliance and satisfaction appear high and the use of other analgesic therapies to treat osteoarthritis pain is reduced in most cases following administration of bedinvetmab.

Pulsed shortwave electromagnetic field therapy increases quality of life in canines with symptoms of osteoarthritics

BACKGROUND

Joint stiffness, lameness and reduced activity levels are common inflammatory responses observed in canines and have significant impact on quality of life (QOL). The symptoms are often ascribed to osteoarthritis (OA), for which the standard treatment is systemic anti-inflammatories, but pharmacologic intervention can have significant short-term and long-term side effects.

OBJECTIVES

Test the efficacy of a Food and Drug Administration (FDA)-cleared pulsed shortwave therapy (PSWT) device as a means to modulate vagus nerve activity and initiate a systemic anti-inflammatory response to determine its ability to improve functionality and the QOL of canines with inflammatory symptoms commonly associated with OA.

METHODS

A randomized, double-blinded, placebo-controlled 14-day study of 60 dogs with a presumptive prior diagnosis of OA in at least one limb joint. Two outcomes assessing changes in the dog's QOL and functionality were measured: subjectively determined changes in eight behaviours associated with discomfort and objectively determined changes in passive range of motion (PROM). The device was secured near the cervico-thoracic region of the dog's spine. PROM measures were taken at baseline and at the end of study. Behavioural measures were taken daily.

RESULTS

Forty-nine animals completed the study. No negative side effects were reported. Average subjective discomfort scores for the treatment group (N = 26) were reduced from 3.74 to 2.10 (44%), compared to no improvement in the placebo group (N = 23) over the study period (p = 0.0001). Average PROM scores increased by 5.51 (4.59-6.23) degrees relative to the placebo group (p < 0.01). Ninety-six per cent of the treatment group showed either increased PROM or improved behavioural changes or both, compared to 4% for the placebo group (p < 0.01). Most changes occurred within the first 8 days of treatment.

CONCLUSIONS

PSWT applied at the level of the cervico-thoracic spine to target the vagus nerve may have the potential to improve QOL in dogs manifesting behaviours commonly associated with OA.

Intravenous injection of equine mesenchymal stem cells in dogs with articular pain and lameness - A feasibility study

Osteoarthritis (OA) is a frequently occurring joint disorder in veterinary practice. Current treatments are focused on pain and inflammation; however, these are not able to reverse the pathological condition. Mesenchymal stem cells (MSCs) could provide an interesting alternative because of their immunomodulatory properties. The objective of this study was to evaluate the potential of a single intravenous injection of xenogeneic equine peripheral blood-derived MSCs (epbMSCs) as treatment for articular pain and lameness. Patients with chronic articular pain were intravenously injected with epbMSCs. They were evaluated at three time points (baseline and 2 follow-ups) by a veterinarian based on an orthopedic joint assessment and an owner canine brief pain inventory scoring. 35 Thirty-five dogs were included in the safety and efficacy evaluation of the study. Results showed that the ePB-MSC therapy was well tolerated with no treatment related adverse events and no increase in articular heat or pain. A significant improvement of lameness, range of motion, joint effusion, pain severity and interference scores was found 6 weeks post-treatment compared to baseline. This study demonstrates that future research on intravenous administration of epbMSCs is warranted to further explore its possible beneficial effects in dogs with chronic articular pain and lameness.

Advances in the pharmaceutical treatment options for canine osteoarthritis

Canine osteoarthritis is a significant cause of pain in many dogs and can therefore compromise animal welfare. As the understanding of the biology and pain mechanisms underpinning osteoarthritis grows, so do the number of treatments available to manage it. Over the last decade, there have been a number of advances in the pharmaceutical treatment options available for dogs with osteoarthritis, as well as an increasing number of clinical trials investigating the efficacy of pre-existing treatments. This review aims to examine the current evidence behind pharmaceutical treatment options for canine osteoarthritis, including non-steroidal anti-inflammatory drugs, piprants, monoclonal antibodies, adjunctive analgesics, structure modifying osteoarthritis drugs and regenerative therapies.

Revealing the Photophysical and Photochemical Reaction Processes of Carprofen in Different Solutions via Ultrafast Femtosecond to Nanosecond Transient Absorption

Carprofen (CP), one kind of a nonsteroidal anti-inflammatory drug, exhibits phototoxic side effects in physiology, while its phototoxic mechanism is ambiguous. To uncover CP's photophysical and photochemical reaction processes, femtosecond to nanosecond transient absorption spectroscopies were employed to directly detect excited states and transient intermediates of CP upon UV irradiation in pure acetonitrile (MeCN), MeCN/water 1:1, and acid/alkaline buffer solutions. The transient absorption data together with DFT calculations were integrated to elucidate mechanisms for photochemical reactions of CP in different solutions. The associated photophysical and photochemical reaction pathways are dependent on various solution environments. In a pure MeCN solvent, CP is excited to a singlet state (S₁) and rapidly interacts with the solvent to proceed solvent rearrangement (SR). It then undergoes vibrational cooling (VC) and proceeds intersystem crossing (ISC) to produce the lowest triplet state (³CP). ³CP finally decays to the ground state. While in a MeCN/water 1:1 solution, deprotonated S₁ of CP experiences SR and VC processes, and then it is promoted to a deprotonated triplet state (³CP^-). ³CP^- undergoes the parallel reactions: dechlorination to a phenyl radical (²CP^-) and decarboxylation to a T₁ anion (³CP^-(de-CO₂)). Finally, both intermediates produce the radical anion species ²CP^-(de-CO₂). In a pH = 7.4 (MeCN/PBS 1:1) solution, ³CP^- can be converted into ²CP^-(de-CO₂) more quickly. Interestingly, we found that the dechlorination step can be promoted in an alkaline solution. Phenyl and chlorine radicals produced in an aqueous solution may be the root cause of the drug's harmful side effects on the human body. This may be useful to guide the design of related CP drugs with minimal phototoxicity in the pharmaceutical process.

A randomised controlled masked clinical trial of two treatments for osteoarthritis in dogs

The product 4CYTE™ Canine (Interpath Pty Ltd., Ballarat, Victoria, Australia) contains four active ingredients: three marine-derived ingredients and Epiitalis®, which is extracted from the seed of the plant Biota orientalis. Carprofen is a non-steroidal anti-inflammatory drug (NSAID) licensed for the treatment of osteoarthritis in dogs and is the active ingredient in several licensed products. This study aimed to compare the efficacy of 4CYTE Canine with carprofen for the treatment of pain from osteoarthritis. The trial was a randomised, masked, parallel group trial in dogs with naturally occurring osteoarthritis. Sixty-nine dogs with body weight of between 10 and 50 kg were enrolled in the study, of which 66 (95.7%) completed the study. The 4CYTE Canine was administered at 60 mg active/kg daily and carprofen at 2-4 mg/kg daily, with a loading dose of up to 4 mg/kg on the first day. The trial duration was 28 days. The primary outcome was defined as improvement in Owner Lameness Score at Day 28 compared with Day 0. Other outcomes measured included Veterinary Lameness Scores and the Owner Mobility Scores. At Day 28, 14 of 29 (48.3%) dogs that received 4CYTE Canine and 13 of 37 (35.1%) dogs that received carprofen had improved. The 4CYTE Canine was found to be non-inferior to carprofen at Day 14 for the Owner Mobility Score and at Day 28 for all three outcomes. This response pattern suggests that improvement in response to 4CYTE Canine continued between Days 14 and 28. These results support the conclusion that 4CYTE Canine is not inferior to carprofen by end-point clinical efficacy.

Beneficial effects of Vigna angularis extract in osteoporosis and osteoarthritis

In Asia, Vigna angularis (azuki bean) has been used as a traditional medicine to treat various diseases because of its biological properties. Osteoarthritis (OA) and osteoporosis (OP) are common regenerative bone diseases that are characterized by deterioration of joint and bone structure. In this study, we evaluated the effects of Vigna angularis extract (VAE) on monosodium iodoacetate (MIA)-induced OA and ovariectomy (OVX)-induced OP models. In the MIA-induced OA results, severe OA was alleviated by the administration of VAE. Extensive local damage in the cartilage and hemorrhagic and edematous of surrounding tissues were decreased by VAE treatment. Articular cartilage was almost intact except for a focal mild abrasion, and the surface was glistening, similar to that of the normal joint. In the OVX-induced OP results, bone mineral content (BMC) and bone mineral density (BMD) were recovered by VAE treatment, and it improved the microstructures of bone. These results show that VAE could inhibit OA and OP symptoms.

Oral Transmucosal Cannabidiol Oil Formulation as Part of a Multimodal Analgesic Regimen: Effects on Pain Relief and Quality of Life Improvement in Dogs Affected by Spontaneous Osteoarthritis

Simple Summary

Osteoarthritis is a progressive and degenerative condition that affects dog populations, causing pain. The pain associated with osteoarthritis is considered to be chronic, owing to both active inflammation and to a maladaptive component caused by central sensitization. Chronic pain in dogs is being increasingly recognised as a significant problem, and finding successful treatments against canine osteoarthritis-related pain is challenging. The aim of this study was to assess the efficacy in pain management over a twelve-week period of oral transmucosal cannabidiol, in combination with a multimodal pharmacological protocol, in dogs affected by spontaneous osteoarthritis. Dogs receiving oral transmucosal cannabidiol in addition to an anti-inflammatory drug, gabapentin and amitriptyline showed a meaningful improvement in Canine Brief Pain Inventory scores, in comparison with dogs that did not receive cannabidiol. The present study suggests that the addition of oral transmucosal cannabidiol to a multimodal pharmacological treatment for canine osteoarthritis improves owner reported pain scores and quality of life of dogs, without severe adverse effects.

Abstract

The aim of this study was to evaluate the efficacy of oral transmucosal (OTM) cannabidiol (CBD), in addition to a multimodal pharmacological treatment for chronic osteoarthritis-related pain in dogs. Twenty-one dogs were randomly divided into two groups: in group CBD (n = 9), OTM CBD (2 mg kg⁻¹ every 12 h) was included in the therapeutic protocol (anti-inflammatory drug, gabapentin, amitriptyline), while in group C (n = 12), CBD was not administered. Dogs were evaluated by owners based on the Canine Brief Pain Inventory scoring system before treatment initiation (T0), and one (T1), two (T2), four (T3) and twelve (T4) weeks thereafter. Pain Severity Score was significantly lower in CBD than in C group at T1 (p = 0.0002), T2 (p = 0.0043) and T3 (p = 0.016). Pain Interference Score was significantly lower in CBD than in C group at T1 (p = 0.0002), T2 (p = 0.0007) and T4 (p = 0.004). Quality of Life Index was significantly higher in CBD group at T1 (p = 0.003). The addition of OTM CBD showed promising results. Further pharmacokinetics and long-term studies in larger populations are needed to encourage its inclusion into a multimodal pharmacological approach for canine osteoarthritis-related pain.

Treatment of canine osteoarthritis with allogeneic platelet-rich plasma: review of five cases

Background:

Osteoarthritis (OA) is a major cause of chronic pain and lameness in dogs. Platelet-rich plasma (PRP) is a concentrate of growth and differentiation factors from the blood, which can be used in regenerative medicine strategies.

Aim:

The main aim of this study was to evaluate the effect of allogeneic PRP on the treatment of canine OA.

Methods:

Five dogs from several breeds, between 6 and 12 years old, and from both genders were studied. Clinical and imageological examinations diagnosed OA in the knee, tibiotarsal, elbow, and intercarpal joints. These dogs were refractory to medical therapy and to physical rehabilitation protocols that included shockwave therapy, laser therapy, electrostimulation, hydrotherapy, and diathermy.

Animals were treated with allogeneic PRP obtained from the blood of the five dogs, which was processed in a pool. Echoguided intra-articular PRP injection was administered under sedation and after aseptic field preparation. Lameness at walk and trot (five grades) and pain (five scores) were evaluated before treatment and 30, 60, and 90 days post-treatment.

Results:

All animals presented improvements at 30 and 60 days in both parameters. Four dogs showed a decrease of three grades of lameness after 90 days and there was complete absence of lameness in 2 days. Pain was reduced from severe and moderate to mild in all the dogs after 30 days, and among them, three revealed no pain after 90 days.

Conclusion:

This study sheds light on the applicability and safety of a single administration of allogeneic PRP in osteoarthritic dogs.

Kinetic analysis of canine gait on the effect of failure tendon repair and tendon graft

Kinetic analysis of canine gait has been extensively studied, including normal and abnormal gait. However, no research has looked into how flexor tendon injury and further treatment would affect the walking pattern comparing to the uninjured state. Therefore, this study was aimed to utilize a portable pressure walkway system, which has been commonly used for pedobarographic and kinetic analysis in the veterinary field, to examine the effect of a failed tendon repair and tendon graft reconstruction on canine digit kinetics during gait. 12 mixed breed (mongrel) hound-type female dogs were included in this study and 2^nd and 5^th digits were chosen to undergo flexor tendon repair and graft surgeries. Kinetic parameters from the surgery leg in stance phase were calculated. From the results, after tendon failure repair, decrease of weight bearing was seen in the affected digits and weight bearing was shifted to the metacarpal pad. After tendon graft reconstruction, weight bearing returned to the affected digits and metacarpal pads. Slight alteration in peak pressure and instant of peak force were identified, but it was estimated to have little influence on post-reconstruction gait. This study could serve as a reference in evaluating canine digit function in flexor tendon injury for future studies.

Conservative Management of Hip Dysplasia

Hip dysplasia (HD) is a common orthopedic condition seen in small animal patients that leads to osteoarthritis of the coxofemoral joint. The disease can be managed conservatively or surgically. The goals of surgical treatment in the immature patient are to either prevent the clinical signs of HD or to prevent or slow the progression of osteoarthritis. In mature patients surgery is used as a salvage procedure to treat debilitating osteoarthritis. Conservative management can be used in dogs with mild or intermittent clinical signs and includes nutritional management and weight control, exercise modification, physical rehabilitation, pain management and disease-modifying agents.

Efficacy of an oral nutraceutical for the treatment of canine osteoarthritis. A double-blind, randomized, placebo-controlled prospective clinical trial

OBJECTIVES

To assess the safety and efficacy of an orally administered nutraceutical (Glu/CS+; + for additional ingredient) for the treatment of clinical osteoarthritis (OA) in dogs.

METHODS

In this double-blind, randomized, placebo-controlled clinical trial, client-owned dogs with clinical signs of OA in one or more joints were assigned to a Glu/CS+ (n = 30) or placebo (n = 30) group. Dogs were administered Glu/CS+ or placebo orally and wore an activity monitor (AM) continuously throughout a 97 day study period. Prior to the initiation of the treatment, seven days of baseline activity was collected. On days -7, 30, 60 and 90 of the study, owners completed a patient assessment form (Canine Brief Pain Inventory). Data between groups were compared.

RESULTS

No serious adverse events were reported. No difference was found between groups when evaluating daily activity counts during the seven-day pre-treatment period and the 90-day treatment period. Owner assessment (pain interference and pain severity scores) improved over the 90-day treatment period for both groups, however no difference was found between treatment groups.

CONCLUSIONS

Treatment with oral Glu/CS+ for a 90 day treatment period when compared to placebo treatment did not result in a significant increase in activity counts in dogs with clinical OA. However, owner assessment scores similarly improved throughout the study period for dogs in both groups, suggesting a caregiver placebo effect in this outcome measure.

Gastritis and Gastric Ulcers in Working Dogs

Gastritis and gastric ulcers are an important cause of morbidity and mortality in canine athletes. Although the majority of scientific work on this condition has been performed in ultraendurance racing sled dogs, this condition has been identified in other canine athletes, including sled dogs competing in shorter events and dogs performing off-leash explosive detection duties. The cause of the syndrome is unknown, but current hypotheses propose a link between exercise-induced hyperthermia and loss of gastric mucosal barrier function as an early event in the pathogenesis. Treatment is focused on prevention of clinical disease using acid secretion inhibitors, such as omeprazole, which has excellent efficacy in controlled clinical studies.

Brachystemma calycinum D. Don Effectively Reduces the Locomotor Disability in Dogs with Naturally Occurring Osteoarthritis: A Randomized Placebo-Controlled Trial

Objective. The aim of this randomized placebo-controlled trial was to evaluate the beneficial effect of a whole plant extract of Brachystemma calycinum D. Don (BCD) in naturally occurring osteoarthritis (OA) in dogs. Methods. Dogs had stifle/hip OA and poor limb loading based on the peak of the vertically oriented ground reaction force (PVF) measured using a force platform. At baseline, PVF and case-specific outcome measure of disability (CSOM) were recorded. Dogs (16 per group) were then assigned to receive BCD (200 mg/kg/day) or a placebo. The PVF was measured at week (W) 3 and W6. Locomotor activity was recorded throughout the study duration using collar-mounted accelerometer, and CSOM was assessed biweekly by the owner. Results. BCD-treated dogs had higher PVF at W3 and W6 when compared to Baseline (P < 0.001) and at W6 when compared to placebo-treated dogs (P = 0.040). Higher daily duration (P = 0.024) and intensity (P = 0.012) of locomotor activity were observed in BCD-treated dogs compared to baseline. No significant change was observed in either group for CSOM. Conclusions. Treatment with BCD improved the limb impairment and enhanced the locomotor activity in dogs afflicted by naturally-occurring OA. Those preclinical findings provide interesting and new information about the potential of BCD as an OA therapeutic.

Production of canine mesenchymal stem cells from adipose tissue and their application in dogs with chronic osteoarthritis of the humeroradial joints

Autologous AD-MSC [adipose-derived MSC (mesenchymal stem cell)] therapy involves harvesting fat from the patient by isolating the stem and regenerative cells and administering the cells back to the patient. This study evaluated the production of canine AD-MSCs and their possible application in cellular therapy for dogs. To assess whether cellular therapy can replace drug therapy, the clinical effect of a single intra-articular injection of AD-MSCs was evaluated on 4 dogs with lameness associated with OA (osteoarthritis) of the humeroradial joints. MSCs were readily isolated from adult dog adipose tissue, and their ability to form colony and differentiate into various phenotypes was confirmed. AD-MSCs expressed OCT4, NANOG and SOX2 at the mRNA level, pluripotency markers usually ascribed to embryonic stem cells. The results suggest the stemness of the cells isolated from canine fat, and good quality control made them available for both experimental and clinical use. Follow-up studies to evaluate the effects of AD-MSC therapy showed that OA of the elbow joints improved with time, indicating significant potential for clinical use in the treatment of lameness, particularly when administered before the injury becomes severe.

Assessment of veterinary practitioners in the British Isles' approaches towards the management of canine osteoarthritis

The aim of this questionnaire-based retrospective study was to ascertain veterinary practitioners in the British Isles' approaches to osteoarthritis in dogs. The Mann-Whitney U test, Kruskal-Wallis test and multiple ordinal logistic regression were used to compare demographic data with treatment options. Questionnaires were returned by 228 practitioners (a response rate of 22.8 per cent). The majority of responses were from males (70 per cent). Eighty-six per cent (188 of 220) of the respondents had graduated from veterinary schools in the UK and Ireland. Veterinarians who had graduated less recently used exercise modulation less frequently (P<0.004, odds ratio [OR]=1.06) and ranked exercise modulation as less important (P=0.008, OR=1.04). Veterinarians who had graduated outside the UK or Ireland were less likely (P=0.033, OR=0.46) to use exercise modulation than those who had graduated in the UK or Ireland. Veterinarians who had graduated more recently were less likely (P=0.008, OR=0.95) to use medications. Female veterinary surgeons were less likely to rank medications as important (P<0.0001, OR=0.29) and less likely to rank corticosteroids as important (P=0.046, OR=0.42) than male veterinary surgeons. Practitioners who had graduated outside the UK or Ireland were less likely (P=0.01, OR=0.30) to rank corticosteroids as important. There was a significant mild negative correlation between the frequency of use of structure-modifying osteoarthritis drugs (SMOADs) and practitioners' opinions on rank importance (-0.32, P<0.0001). Medications such as SMOADs and nutraceuticals were ranked as not important but were used frequently. Overall, age, sex, the university of graduation and the number of canine consultations per day had an impact on the practitioners' treatment protocols.

Synovial cyst of the fifth digit in a cat

A synovial cyst of the fifth digit of the left forelimb in a 15-year-old cat was diagnosed. Radiographs showed severe osteoarthritis of the interphalangeal and metacarpophalangeal joints with soft tissue swelling. An ultrasound examination of the digit revealed a cystic structure. Following amputation of the digit, the cyst recurred 3 months later palmar to the carpus and metacarpus. The aetiology of synovial cysts is discussed.

Pathophysiology of cyclooxygenase inhibition in animal models

Cyclooxygenase (COX) catalyzes the conversion of arachidonic acid into prostaglandins (PGs), which play a significant role in health and disease in the gastrointestinal tract (GI) and in the renal, skeletal, and ocular systems. COX-1 is constitutively expressed and found in most normal tissues, whereas COX-2 can be expressed at low levels in normal tissues and is highly induced by pro-inflammatory mediators. Inhibitors of COX activity include: (1) conventional nonselective, nonsteroidal anti-inflammatory drugs (ns-NSAIDs) and (2) COX-2 selective nonsteroidal anti-inflammatory drugs (COX-2 s-NSAIDs). Inhibition of COX-1 often elicits GI toxicity in animals and humans. Therefore, COX-2 s-NSAIDs were developed to provide a selective COX-2 agent, while minimizing the attendant COX-1-mediated GI toxicities. Rats and dogs overpredict COX inhibition for renal effects such as renal handling of electrolytes in humans. COX inhibitors are shown to have both beneficial and detrimental effects, such as on healing of ligament or tendon tears, on the skeletal system in animal models. Certain ophthalmic conditions such as glaucoma and keratitis are associated with increased COX-2 expression, suggesting a potential role in their pathophysiology.

Influencing factors of ADP-induced, epinephrine-induced and ristomycin-induced platelet aggregation in dogs

Functional defects of platelets are often studied by in-vitro aggregation tests with chemical compounds such as ADP, epinephrine and ristomycin (ristocetin). The aim of the present work was to investigate the effect of some diseases and that of nonsteroidal anti-inflammatory drug treatment on platelet aggregation in dogs. The examination had been carried out on 115 dogs by a Carat TX4 optical aggregometer (Entec GmbH, Ilmenau, Germany) first used in veterinary practice. The dogs were divided in three groups: healthy (control) dogs (n = 43), diseased dogs with normal haemostasis profile (n = 44), and dogs suffering from arthropathies with normal haemostasis profile treated with the nonsteroidal anti-inflammatory drugs ketoprofen or carprofen (n = 21). Following establishment of normal platelet aggregation curves in healthy dogs we found that some diseases such as diabetes mellitus, Cushing's disease, mastocytoma and lymphoma increased or decreased the aggregation maximum of platelets or caused changes in the feature of the aggregation curve. Carprofen treatment had no effect on platelet aggregation while ketoprofen decreased the aggregation maximum. These results showed that Carat TX4 aggregometer proved a useful instrument in studying platelet aggregation in platelet-rich plasma of dogs. For clinical pathologists it is important to know that the effects of some diseases and nonsteroidal anti-inflammatory drug treatments have to be taken into account when in-vitro platelet aggregation is evaluated. Based on our results and on those of other studies, we think standardization in aggregation methodology is highly recommended in veterinary laboratories.

Human telomerase reverse transcriptase (hTERT) extends the lifespan of canine chondrocytes in vitro without inducing neoplastic transformation

To determine if the exogenous expression of the human telomerase reverse transcriptase (hTERT) protein can extend the in vitro lifespan of chondrocytes from normal and osteoarthritic canine donors, articular chondrocytes were harvested and expanded initially in monolayer culture. Cells were transfected with pCIneo or pCIneo-hTERT and selected using G418. Transfectants were cultured either in monolayer or alginate beads and telomerase activity, replicative lifespan and the tumourogenic potential of the transfected cells were assessed. hTERT expression in canine chondrocytes prolonged the replicative lifespan of these cells but did not permit growth in low serum conditions or promote the formation of foci in anchorage independence assays. In addition, hTERT expression resulted in the down-regulation of MMP-1. This suggests that hTERT may represent a tool for the generation of tissue engineered chondrocytes suitable for autologous re-implantation into the affected areas of osteoarthritic joints.

Evaluation of the effect of ketoprofen and carprofen on platelet function in dogs studied by PFA-100 point-of-care analyser

The effect of two nonsteroidal anti-inflammatory drugs (carprofen and ketoprofen) on platelet adhesion and aggregation functions was evaluated by the PFA-100 analyser (Dade-Behring, CA, U.S.A.) using its collagen-adenosine diphosphate (ADP) and collagen-epinephrine (EPI) cartridges. The function of platelets was evaluated in 55 healthy dogs, in 7 dogs treated with ketoprofen and in 31 dogs treated with carprofen in a therapeutic dose for minimum 5 days. The therapeutic doses of carprofen had no effect on the closure time of PFA-100 (which is the marker of platelet function) but ketoprofen caused a significant increase when using collagen-EPI stimulation The closure times for both the healthy (control) and the treated dogs using EPI cartridges were often longer than the upper default cut-off point (300 sec) of the device. The PFA-100 analyser with collagen-ADP cartridges could be a useful tool for veterinary applications including the evaluation of platelet aggregation in dogs treated with NSAIDs. The upper cut-off point of PFA-100 might be extended.

Stabilisation of medial shoulder instability by imbrication of the subscapularis muscle tendon of insertion

OBJECTIVES

To evaluate the efficacy of subscapularis muscle tendon of insertion imbrication as a treatment for medial shoulder instability.

METHODS

Medial shoulder instability was diagnosed in five dogs. Initial management with medical or arthroscopic treatment failed to fully resolve lameness in four of the cases. Each case was treated by subscapularis muscle tendon of insertion imbrication. An anatomical model of medial shoulder instability was used to assess the effect of subscapularis muscle tendon of insertion imbrication on the angle of abduction of the shoulder.

RESULTS

In clinical study, subscapularis muscle tendon of insertion imbrication was performed in five cases. Lameness resolved fully in three cases and partially in two cases. In cadaver study, transection of either the subscapularis muscle tendon of insertion or the subscapularis muscle tendon of insertion and medial glenohumeral ligament significantly increased the angle of abduction. Imbrication of the subscapularis muscle tendon of insertion significantly reduced the angle of abduction. No significant differences were noted between the angle of abduction of normal shoulder and the shoulder with medial shoulder instability treated by subscapularis muscle tendon of insertion imbrication.

CLINICAL SIGNIFICANCE

Subscapularis muscle tendon of insertion imbrication is a moderately effective procedure for the management of medial shoulder instability unresponsive to medical and/or arthroscopic management. The angle of abduction of the shoulder was returned to normal in model of medial shoulder instability, following subscapularis muscle tendon of insertion. Subscapularis muscle tendon of insertion imbrication provides a relatively simple method of treating medial shoulder instability in dogs.

The Interaction between Orally Administered Non-Steroidal Anti-Inflammatory Drugs and Prednisolone in Healthy Dogs

The interaction between oral non-steroidal anti-inflammatory drugs (NSAIDs) and prednisolone administered concurrently for 30 days was studied in 18 healthy dogs divided into 3 groups of 6 dogs each: a drug-free negative control group (NC group) given 2 gelatin capsules; a group given meloxicam (0.1 mg/kg) and prednisolone (0.5 mg/kg) (MP group); and a group given a reduced dosage of ketoprofen (0.25 mg/kg, p.o.) and prednisolone (0.5 mg/kg, p.o.) (KP group). The dogs were periodically monitored by physical examinations, blood analyses, endoscopic examinations, fecal occult blood tests, renal function tests [effective renal plasma flow (ERPF) and glomerular filtration rate (GFR)], urinalyses [urinary sediments, and urinary micro-albumin to creatinine ratio (UAlb/Cre)], urinary enzyme indices, and haemostatic function tests [buccal mucosa bleeding time (BMBT), cuticle bleeding time (CBT)]. Significant changes were observed in the KP group, including a decrease of ERPF and GFR, an increased UAlb/Cre ratio, prolonged BMBT and CBT, as well as the presence of more severe grades of endoscopic lesions and fecal occult blood. In both the MP and KP groups, abnormal enzymuria with exfoliation of renal tubular epithelial cells in the urine was found. However, no significant changes in any of the other tests were observed in the MP group compared with the NC group. These findings suggest that the combination of NSAIDs, even selective COX-2 inhibitors, with prednisolone may be contraindicated due to the potential for serious adverse effects on the kidneys, the platelets, and the gastrointestinal tract.

Effects of cyclooxygenase inhibition on the gastrointestinal tract

Cyclooxygenase (COX) is a rate-limiting enzyme that catalyzes the conversion of arachidonic acid, an essential fatty acid present in cell membrane phospholipids and liberated by phospholipase, into prostaglandins (PGs) and prostanoids. COX has two distinct membrane-anchored isoenzymes; COX-1 and COX-2. COX-1 is a constitutively expressed and found in most normal body tissues; COX-2 is expressed in normal tissues at low levels and is highly induced by pro-inflammatory mediators in the setting of inflammation, injury, and pain. Inhibitors of COX activity include: (1) conventional non-selective non-steroidal anti-inflammatory drugs (ns-NSAIDs); (2) selective COX-2 inhibitors (COXIBs); and (3) COX-1 inhibitors. Non-selective NSAIDs, at therapeutic doses, inhibit both COX-1 and COX-2. The anti-inflammatory benefits of these drugs are primarily derived from COX-2 inhibition, while inhibition of COX-1 often elicits gastrointestinal (GI) toxicity. Therefore, COXIBs were developed to provide a selective COX-2 agent, i.e., one, that at fully therapeutic doses demonstrated comparable therapeutic benefit to non-selective NSAIDs, without the attendant COX-1-mediated GI toxicities. In this review, we evaluate available literature describing the pathophysiologic role of cyclooxygenases and the effects of their inhibition in GI system in experimental and domestic animal species.

Safety of reduced-dosage ketoprofen for long-term oral administration in healthy dogs

OBJECTIVE

To evaluate the safety of reduced-dosage ketoprofen (RDKET) for long-term oral administration in healthy dogs.

ANIMALS

14 healthy Beagles.

PROCEDURES

Racemic ketoprofen (0.25 mg/kg, PO) and gelatin capsules, as a drug-free placebo, were each administered to 7 dogs for 30 days. Dogs were periodically monitored via physical examination, blood analyses, endoscopic examinations, fecal occult blood tests (tetramethylbenzidine and guaiac methods), renal function tests (effective renal plasma flow and glomerular filtration rate), urinalyses, urinary enzyme indices (N-acetyl-beta-D-glucosaminidase and gamma-glutamyl-transferase), and hemostatic function tests (buccal mucosa bleeding time, cuticle bleeding time, prothrombin time, activated partial thromboplastin time, and fibrinogen concentration).

RESULTS

Pyloric antrum lesion grade was significantly higher in the RDKET group on day 28, compared with the pretreatment and control group grades. Fecal occult blood grade measured by use of the tetramethylbenzidine method was significantly higher in the RDKET group on day 30, compared with the pretreatment grade. No other significant differences were detected between treatment groups.

CONCLUSIONS AND CLINICAL RELEVANCE

RDKET induced mild to moderate gastric mucosal injuries especially in the pyloric antrum in healthy Beagles, whereas no adverse effects were observed in renal function or hemostasis. Fecal occult blood tests may be useful as screening tests for adverse gastrointestinal effects induced by RDKET in dogs.

Use of force plate analysis to assess the analgesic effects of etodolac in horses with navicular syndrome

OBJECTIVE

To evaluate the musculoskeletal analgesic effect of etodolac administered PO every 12 or 24 hours in chronically lame horses by use of force plate analysis.

ANIMALS

22 horses with navicular syndrome.

PROCEDURE

Horses received etodolac (23 mg/kg, PO, q 12 h; n = 7), etodolac (23 mg/kg, PO, q 24 h; 8), or corn syrup (20 mL, PO, q 24 h; control treatment; 7) for 3 days. Combined forelimb peak vertical ground reaction force (PVF) was measured via force plate analysis before the first treatment (baseline) and at 6, 12, 24, and 36 hours after the last treatment. Differences in mean PVF (mPVF) between baseline and subsequent measurements were analyzed (repeated-measures ANOVA) and evaluated for treatment and time effects and treatment-time interaction.

RESULTS

Once- or twice-daily administration of etodolac resulted in significant increases in mPVF from baseline at 6, 12, and 24 hours after the last treatment, compared with the control treatment. There were no significant differences in mPVF between the etodolac treatment groups at any time point. In both etodolac treatment groups, there was a significant increase in mPVF from baseline at 6, 12, and 24 hours, compared with that at 36 hours. Etodolac-associated adverse effects were not detected.

CONCLUSIONS AND CLINICAL RELEVANCE

In horses with navicular syndrome, once-daily oral administration of 23 mg of etodolac/kg appears to provide effective analgesia for as long as 24 hours. Twice-daily administration of etodolac at this same dose does not appear to provide any additional analgesic efficacy or duration of effect.

The Effects of Epidural Deracoxib on the Ground Reaction Forces in an Acute Stifle Synovitis Model

OBJECTIVE

To evaluate the efficacy of epidurally administered deracoxib to mediate the signs of a sodium urate crystal-induced stifle synovitis in dogs, and to compare the efficacy of epidural versus subcutaneously administered deracoxib.

STUDY DESIGN

Experimental, randomized, blinded, placebo-controlled modified cross-over design.

ANIMALS

Random source, adult, mixed breed dogs (n = 24; 14 males, 10 females).

METHODS

Sodium urate crystals were used to create a stifle synovitis model to evaluate the efficacy of deracoxib. Dogs were divided into 4 groups: 3 mg/kg epidural deracoxib, 1.5 mg/kg epidural deracoxib, 3 mg/kg subcutaneous deracoxib, and a placebo (vehicle for deracoxib). Force plate and subjective evaluations were made at time 0, 2, 4, 8, 12, and 24 hours post-treatment. Repeated measures ANOVA with Bonferroni-corrected post hoc comparisons was used to determine significant treatment effects.

RESULTS

Peak vertical force (PVF) and vertical impulse (VI) were both significantly higher in deracoxib treated dogs compared with placebo. For 3 mg/kg epidural and subcutaneous deracoxib, PVF and VI were significantly greater than for 1.5 mg/kg epidural deracoxib. Overall pain score for all deracoxib-treated dogs was significantly lower than for placebo dogs.

CONCLUSIONS

Epidural administration of deracoxib is effective at providing analgesia in an acute joint pain model; however, it does not appear to be more effective than systemic administration.

CLINICAL RELEVANCE

Injectable deracoxib is effective in providing analgesia in acute inflammatory conditions of synovial joints.

Developmental orthopedic disease

Developmental orthopedic diseases are a common cause of pain and lameness in young dogs. Most occur in large-breed dogs with rapid growth rates. This article reviews the signalment, etiology and pathogenesis, clinical signs, diagnosis, treatment, and prognosis for many of the common developmental orthopedic diseases, including hypertrophic osteodystrophy, panosteitis, osteochondrosis, Legg-Calve-Perthes disease, hip dysplasia, elbow dysplasia, and pes verus.

Rehabilitation for the Orthopedic Patient

An understanding of orthopedic conditions and their medical and surgical treatment is important to help the therapist develop a treatment plan that will help the patient return to function quickly with minimal complications. The therapist must constantly assess the patient for improvement or complications and adjust the therapy plan accordingly. Knowledge of the stages of tissue healing and of the strength of tissues is critical to avoid placing too much stress on the surgical site, yet some challenge to tissues must be provided to optimize the return to function.

Gastrointestinal tract perforation in dogs treated with a selective cyclooxygenase-2 inhibitor: 29 cases (2002-2003)

OBJECTIVE

To identify factors associated with gastrointestinal tract perforation in dogs being treated with a selective cyclooxygenase-2 (COX-2) inhibitor (deracoxib).

DESIGN

Retrospective study.

ANIMALS

29 dogs.

PROCEDURE

The Novartis Animal Health pharmacovigilance database was searched for records of dogs treated with deracoxib in which gastrointestinal tract perforation was documented. Results-16 of the 29 (55%) dogs had received deracoxib at a dosage higher than that approved by the FDA for the particular indication being treated, with 25 (86%) dogs having received deracoxib at a dosage > 2 mg/kg/d (0.9 mg/lb/d). Seventeen (59%) dogs had received at least 1 other nonsteroidal anti-inflammatory drug (NSAID) or a corticosteroid in close temporal association (within 24 hours) with deracoxib administration (ie, immediately before or following). In all, 26 (90%) dogs had received deracoxib at a higher-than-approved dosage or had received at least 1 other NSAID or corticosteroid in close temporal association with deracoxib administration. Twenty dogs died or were euthanatized, and 9 survived.

CONCLUSIONS AND CLINICAL RELEVANCE

In dogs with gastrointestinal tract perforation and that had been treated with deracoxib, perforation was most likely attributable to a number of factors. Deracoxib should only be used at approved dosages. Cortico-steroids and other less selective NSAIDs should not be administered in close temporal association with selective COX-2 inhibitors, including deracoxib. Further study is required to define this problem.

In vitro effects and in vivo efficacy of a novel cyclooxygenase-2 inhibitor in cats with lipopolysaccharide-induced pyrexia

OBJECTIVE

To determine cyclooxygenase (COX)-2 selectivity, pharmacokinetic properties, and in vivo efficacy of firocoxib (ML-1,785,713) in cats.

ANIMALS

5 healthy male and 14 healthy female domestic shorthair cats.

PROCEDURE

Selectivity of firocoxib for inhibiting COX-2 was determined by comparing the potency for inhibiting COX-1 with that of COX-2 in feline blood. Pharmacokinetic properties were determined after i.v. (2 mg/kg) and oral (3 mg/kg) administration in male cats. In vivo efficacy was evaluated in female cats with lipopolysaccharide (LPS)-induced pyrexia with administration of firocoxib 1 or 14 hours before LPS challenge.

RESULTS

Blood concentrations resulting in 50% inhibition of COX-1 and COX-2 activity in vitro were 75 +/- 2 microM and 0.13 +/- 0.03 microM, respectively, and selectivity for inhibiting COX-2 relative to COX-1 was 58. Firocoxib had moderate to high oral bioavailability (54% to 70%), low plasma clearance (4.7 to 5.8 mL/min/kg), and an elimination half-life of 8.7 to 12.2 hours. Firocoxib at doses from 0.75 to 3 mg/kg was efficacious in attenuating fever when administered to cats 1 or 14 hours before LPS challenge.

CONCLUSIONS AND CLINICAL RELEVANCE

Firocoxib is a potent COX-2 inhibitor and is the only selective COX-2 inhibitor described for use in cats to date. It is effective in attenuating febrile responses in cats when administered 14 hours before LPS challenge, suggesting it would be suitable for once-a-day dosing. Because selective COX-2 inhibitors have an improved therapeutic index relative to nonselective nonsteroidal anti-inflammatory drugs in humans, firocoxib has the potential to be a safe, effective anti-inflammatory agent for cats.

Treatment of shoulder instability caused by medial glenohumeral ligament rupture with thermal capsulorrhaphy

A three-year-old, male springer spaniel had chronic left forelimb lameness with a medial glenohumeral ligament tear and articular cartilage damage diagnosed on arthroscopy. The animal failed to respond to conservative therapy of rest and an intra-articular injection of methylprednisolone. The use of thermal capsulorrhaphy using bipolar radiofrequency bought about a return of joint stability and resolution of the lameness.

Nonsteroidal anti-inflammatory drugs in veterinary ophthalmology

Uveitis is a common sequela to many ocular diseases. Primary treatment goals for uveitis should be to halt inflammation, prevent or control complications caused by inflammation, relieve pain, and preserve vision. Systemic and topical NSAIDs are essential components of the pharmaceutic armamentarium currently employed in the management of ocular inflammation by general practitioners and veterinary ophthalmologists worldwide. NSAIDs effectively prevent intraoperative miosis; control postoperative pain and inflammation after intraocular procedures, thus optimizing surgical outcome; control symptoms of allergic conjunctivitis;alleviate pain from various causes of uveitis; and circumvent some of the unwanted side effects that occur with corticosteroid treatment. Systemic NSAID therapy is necessary to treat posterior uveitis, because therapeutic concentrations cannot be attained in the retina and choroid with topical administration alone, and is warranted when diseases, such as diabetes mellitus or systemic infection, preclude the use of systemic corticosteroids. Risk factors have been identified with systemic and topical administration of NSAIDs. In general, ophthalmic NSAIDs may be used safely with other ophthalmic pharmaceutics; however, concurrent use of drugs known to affect the corneal epithelium adversely, such as gentamicin, may lead to increased corneal penetration of the NSAID. The concurrent use of NSAIDs with topical corticosteroids in the face of significant preexisting corneal inflammation has been identified as a risk factor in precipitating corneal erosions and melts in people and should be undertaken with caution[8]. Clinicians should remain vigilant in their screening of ophthalmic and systemic complications secondary to drug therapy and educate owners accordingly. If a sudden increase in patient ocular pain (as manifested by an increase in blepharospasm, photophobia, ocular discharge, or rubbing)is noted, owners should be instructed to contact their veterinarian promptly.

In vitro effects and in vivo efficacy of a novel cyclooxygenase-2 inhibitor in dogs with experimentally induced synovitis

OBJECTIVE

To determine cyclooxygenase-2 (COX-2) selectivity, pharmacokinetic properties, and in vivo efficacy of ML-1,785,713 in dogs.

ANIMALS

21 healthy male and female mixed-breed dogs and 24 healthy male Beagles.

PROCEDURE

Selectivity of ML-1,785,713 for inhibiting COX-2 was determined by comparing the potency for inhibiting cyclooxygenase-1 (COX-1) with that of COX-2 in canine blood. Pharmacokinetic properties were determined after i.v. (2 mg/kg) and oral (8 mg/kg) administration in female mixed-breed dogs. In vivo efficacy was evaluated in male mixed-breed dogs with urate crystal-induced synovitis. Prophylactic efficacy was evaluated by administering ML-1,785,713 two hours before induction of synovitis whereas therapeutic efficacy was determined by administering ML-1,785,713 one hour after induction of synovitis.

RESULTS

Blood concentrations that resulted in 50% inhibition of COX-1 and COX-2 activity in vitro were 119.1 microM and 0.31 microM, respectively, and selectivity ratio for inhibiting COX-2 relative to COX-1 was 384. ML-1,785,713 had high oral bioavailability (101%), low systemic clearance (77 mL/min/kg), and an elimination half-life of 5.9 hours. ML-1,785,713 was efficacious when administered prophylactically and therapeutically to dogs with urate crystal-induced synovitis.

CONCLUSIONS AND CLINICAL RELEVANCE

ML-1,785,713 is a novel, potent COX-2 inhibitor that is the most selective COX-2 inhibitor described for use in dogs to date. ML-1,785,713 has oral bioavailability and low systemic clearance that is comparable to other non-steroidal anti-inflammatory drugs. It is effective after prophylactic and therapeutic administration in attenuating lameness in dogs with urate crystal-induced synovitis. Drugs that specifically inhibit COX-2 and not COX-1 at therapeutic doses may have an improved tolerability profile, compared with nonselective non-steroidal anti-inflammatory drugs.

Effect of carprofen, etodolac, meloxicam, or butorphanol in dogs with induced acute synovitis

OBJECTIVE

To compare the analgesic and anti-inflammatory effect of single doses of carprofen, etodolac, meloxicam, and butorphanol in dogs with induced acute synovitis (acute pain model) via kinetic gait analysis and orthopedic evaluation and examine measurement of serum C-reactive protein (CRP) concentration as an indicator of treatment efficacy.

ANIMALS

12 Beagles and 6 additional Beagles that were used only in serum CRP analyses.

PROCEDURE

Acute synovitis was induced in right stifle joints of dogs via intra-articular injection of monosodium urate solution. Treatments included butorphanol (0.2 mg/kg, i.v.), carprofen (4 mg/kg, PO), etodolac (17 mg/kg, PO), or meloxicam (0.2 mg/kg, PO); control dogs received no treatment. The procedure was repeated (3-week intervals) until all dogs received all treatments including control treatment. Lameness was assessed on a biomechanical force platform and via orthopedic evaluations of the stifle joints; blood was collected to monitor serum CRP concentration.

RESULTS

Compared with control dogs, treated dogs had significantly different vertical ground reaction forces and weight-bearing scores. Greatest improvement in lameness was observed in carprofen-treated dogs. Etodolac had the fastest onset of action. Compared with butorphanol treatment, only carprofen and etodolac were associated with significantly lower pain scores. An increase in serum CRP concentration was detected after intra-articular injection in all dogs; this change was similar among groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Carprofen, etodolac, and meloxicam had greater efficacy than butorphanol in relief of acute pain. Carprofen was most effective overall. In this acute pain model, serum CRP analysis was not useful to assess drug efficacy.

Randomised, double-blind, placebo-controlled parallel group study of P54FP for the treatment of dogs with osteoarthritis

P54FP is an extract of Indian and Javanese turmeric, Curcuma domestica and Curcuma xanthorrhiza respectively, which contains a mixture of active ingredients including curcuminoids and essential oils. A randomised, double-blind, placebo-controlled, parallel group clinical trial of P54FP as a treatment for osteoarthritis of the canine elbow or hip was conducted to assess its efficacy and safety. Sixty-one client-owned dogs with osteoarthritis were recruited through first-opinion practices and examined at a single centre. After a two-week wash-out period, they were randomly allocated to receive P54FP or a placebo orally twice daily for eight weeks, and were re-examined after four, six and eight weeks of treatment. The effectiveness of the treatment was assessed in terms of the peak vertical force (PVz) and vertical impulse of the affected limbs, as measured with a force platform, by clinical assessments of lameness and joint pain by the investigators, and overall assessments of the response to treatment by the investigators and the owners. The results from 25 P54FP-treated dogs and 29 placebo-treated dogs showed that there was no statistically significant difference between the groups in terms of the PVz of the affected limb. The investigators' overall assessment showed a statistically significant treatment effect in favour of P54FP (P=0.012), but the owners' assessment just failed to reach statistical significance (P=0.063). No serious adverse effects were recorded, but two P54FP-treated dogs and four placebo-treated dogs were withdrawn from the study because their condition deteriorated.

S. Sulfato de condroitina e hialuronato de sódio no tratamento da doença articular degenerativa experimental em cães: aspectos clínicos e radiológicos

Avaliaram-se clínica e radiograficamente os efeitos do sulfato de condroitina e do hialuronato de sódio no tratamento da articulação femorotibiopatelar de cães com doença articular degenerativa (DAD) induzida experimentalmente. Foram utilizados 15 cães, sem raça definida, de ambos os sexos, pesando entre 18 e 25 kg, submetidos à secção artroscópica do ligamento cruzado cranial (LCCr) para desestabilização articular e indução da DAD. Após três semanas de instabilidade articular, o LCCr foi substituído utilizando-se a técnica intra-articular com emprego da fáscia lata. Os animais foram divididos em três grupos de cinco. Nos do grupo I fez-se somente a substituição do LCCr. Os do grupo II receberam 24mg/animal de sulfato de condroitina, via IM, de cinco em cinco dias, totalizando seis aplicações. Os do grupo III foram tratados com hialuronato de sódio na dose de 20mg/animal, via IV, de cinco em cinco dias, num total de três aplicações. Os animais foram observados por 90 dias, e avaliados clinicamente quanto à claudicação, à capacidade de suportar peso no membro afetado, à mensuração da atrofia muscular e à amplitude de movimento articular. Ao final, foram encaminhados para novo exame radiográfico. Os resultados demonstraram que os animais que receberam hialuronato de sódio apresentaram menor grau de claudicação quando comparados com os demais. Ao exame radiográfico observaram-se osteofitose periarticular e esclerose óssea subcondral. Essas alterações foram evidenciadas de forma mais acentuada nos animais tratados com hialuronato de sódio. Clinicamente, pôde-se observar melhor resultado com o hialuronato de sódio do que nos demais grupos, possivelmente devido à sua maior ação na membrana sinovial, reduzindo a dor e o grau de claudicação. O exame radiográfico não foi compatível com a sintomatologia clínica nos cães tratados com hialuronato de sódio.

Effects of carprofen and dexamethasone on canine chondrocytes in a three-dimensional culture model of osteoarthritis

OBJECTIVE

To determine effects of carprofen and dexamethasone on chondrocytes in a culture model of osteoarthritis (OA).

SAMPLE POPULATION

Chondrocytes isolated from articular cartilage of the humeral head of 5 adult dogs.

PROCEDURE

Chondrocytes were harvested, cultured and subcultured in monolayer, and then cultured in a 3-dimensional (3-D) medium. Cells from each dog were distributed into 6 groups with differing content of liquid medium for each 3-D construct (agarose [AG], AG plus interleukin [IL]-1beta, AG plus carprofen [4 microg/mL], AG plus dexamethasone [1 mg/mL], AG plus IL-1beta [20 ng/mL] plus carprofen [4 microg/mL], and AG plus IL-1beta (20 ng/mL) plus dexamethasone (1 mg/mL). On days 3, 6, 12, and 20 of culture, samples from all groups were collected. Liquid media were assayed for glycosaminoglycan, prostaglandin (PG)E2, matrix metalloprotease (MMP)-3, and MMP-13 concentrations. All 3-D constructs were evaluated for viability, cell morphology, proteoglycan staining, and collagen type-II concentration. Total glycosaminoglycan content in each 3-D construct was quantitated by spectrophotometric assay.

RESULTS

Addition of IL-1beta caused a significant loss of cell viability and matrix production. Addition of carprofen or dexamethasone caused significant decreases in PGE2 in the liquid media, and each was minimally effective in protecting chondrocytes against negative effects of IL-1beta.

CONCLUSIONS AND CLINICAL RELEVANCE

Human recombinant IL-1beta resulted in loss of cell viability, alterations in extracellular matrix components, and production of PG and MMP Carprofen and dexamethasone had little effect on cell and matrix variables but did decrease PGE2 concentrations and primarily affected the inflammatory pathway of osteoarthritis.

Effect of carprofen on hemostatic variables in dogs

OBJECTIVE

To evaluate the effect of carprofen on hemostatic variables in clinically normal dogs.

ANIMALS

12 clinically normal Labrador Retrievers.

PROCEDURE

10 dogs (6 females, 4 males) received carprofen (2.2 mg/kg of body weight, PO, q 12 h) for 5 days. Two dogs (untreated control group; 1 female, 1 male) did not receive carprofen. Hemostatic variables (platelet count, activated partial thromboplastin time, prothrombin time, fibrinogen, platelet aggregation, and bleeding time) were assessed for all dogs prior to treatment, on day 5 of treatment, and 2 and 7 days after discontinuation of the drug (days 7 and 12). Serum biochemical variables and Hct were assessed prior to treatment and on days 5 and 12.

RESULTS

In dogs receiving carprofen, platelet aggregation was significantly decreased, and onset of aggregation was significantly delayed on days 5, 7, and 12, compared with pretreatment values. Activated partial thromboplastin time was significantly increased on days 5, 7, and 12 over pretreatment values in treated dogs, but values remained within reference ranges. Significant differences were not detected in buccal mucosal bleeding time, other serum biochemical and hemostatic variables, or Hct, compared with pretreatment values and the internal control group.

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of carprofen for 5 days causes minor but not clinically important alterations in hemostatic and serum biochemical variables in clinically normal Labrador Retrievers. Carprofen is commonly used to treat osteoarthritis and chronic pain in dogs, but prior to this study, its effect on platelet aggregation and hemostatic variables was unknown.

Hind limb lameness in the young patient

Hind limb lameness is seen frequently in young dogs and may result from congenital abnormalities, traumatic injuries, or developmental diseases. An understanding of the patient's history, a good physical and radiographic evaluation, and sound knowledge of the common diseases affecting immature dogs permit early diagnosis and successful treatment in most cases.

Lateral glenohumeral ligament rupture in three dogs

Three adult large breed dogs were evaluated for chronic forelimb lameness. Clinical examination localised pain to the area of the shoulder joint. Traditional imaging methods, including radiography, arthrography and ultrasonography, were unrewarding. Arthroscopy performed via a lateral portal demonstrated complete tears of the proximal part of the lateral glenohumeral ligament in all cases. Two of the three cases responded to treatment with intra-articular methylprednisolone and rest with a resolution of the lameness, while the third failed to improve. Surgical intervention in this third case involved lateral capsulorraphy, and re-examination at five weeks postoperatively showed the dog to be without lameness. Tearing of the lateral glenohumeral ligament should be considered in the differential diagnosis of shoulder lameness. Surgical stabilisation should be considered in cases refractory to conservative treatment.

The effects of methylprednisolone on normal and monocyte-conditioned medium-treated articular cartilage from dogs and horses

OBJECTIVE

To study in vitro (1) the dose-response relationships between proteoglycan metabolism in normal and corticosteroid-treated articular cartilage; (2) long-term proteoglycan metabolism after treatment of articular cartilage with corticosteroids; and (3) the effect of corticosteroids on proteoglycan metabolism in articular cartilage treated with monocyte-conditioned medium (MCM).

STUDY DESIGN

Equine and canine articular cartilage explants were treated with corticosteroids and MCM. Proteoglycan synthesis and degradation were measured by radioactive labeling in short-term culture, and the long-term effect of corticosteroid treatment on proteoglycan metabolism was studied in normal explants.

ANIMALS

Two young cross-breed horses and 3 young Labrador retrievers.

METHODS

Equine articular cartilage explants were incubated in medium containing methylprednisolone sodium succinate (MPS) at 0, .001, .01, .1, 1, and 10 mg/mL (final concentration) for 1 day and then in fresh medium without MPS. Proteoglycan synthesis was measured by incorporation of sodium [35S]sulfate at 1, 3, 7, 10, and 13 days after initial treatment with MPS. Proteoglycan release was measured from separate explants prelabeled with sodium [35S]sulfate and treated similarly. Equine articular cartilage explants were treated with equine MCM simultaneously with, and 24 hours before MPS, at 0, 0.01, 0.1, 1, or 5 mg/mL for 72 hours. Proteoglycan synthesis and degradation in these explants was compared. Proteoglycan synthesis and degradation were measured similarly in canine articular cartilage explants treated simultaneously with canine MCM and MPS at 0, 0.001, 0.01, 0.1, 1 and 10 mg/mL for 72 hours. Equine articular cartilage explants treated with 0, 0.01, 0.1, 1, and 5 mg/mL of MPS for 72 hours were evaluated histologically.

RESULTS

Proteoglycan synthesis in normal equine articular cartilage was severely depressed by 10 mg/mL MPS for 24 hours, and proteoglycan synthesis failed to recover after 13 days of culture in medium without MPS. Cartilage treated with 5 mg/mL MPS had pyknotic chondrocyte nuclei and empty lacunae. Concentrations of 1 and 0.1 mg/mL MPS depressed proteoglycan synthesis in normal equine cartilage explants. For these 2 concentrations, proteoglycan synthesis recovered 2 days after MPS removal and increased significantly (P < .05) 7 days after treatment with MPS compared with controls without MPS. Concentrations of 0.001 and 0.01 mg/mL MPS did not significantly affect proteoglycan synthesis in normal equine cartilage explants. Cumulative proteoglycan loss over 13 days in culture from normal equine explants treated for 24 hours with different concentrations of MPS was not significantly different between treatment groups at any time point. MCM significantly depressed proteoglycan synthesis in both canine and equine articular cartilage explants and significantly increased proteoglycan release. These effects were prevented in the canine explants by simultaneous treatment with MPS at 1 and 0.1 mg/mL, and proteoglycan release induced by MCM in equine articular cartilage was inhibited by 1 mg/mL MPS.

CONCLUSIONS

Concentrations of 1.0 and 0.1 mg/mL MPS alleviated articular cartilage degradation in MCM-treated articular cartilage in vitro. These concentrations of MPS in contact with normal cartilage explants for 24 hours are unlikely to be detrimental in the long term to proteoglycan synthesis. The response of articular cartilage to MPS was affected by treatment with MCM so that results of experiments with normal articular cartilage explants may not reflect results obtained with abnormal cartilage.

CLINICAL RELEVANCE

It may be possible to find an intraarticular concentration of corticosteroid that protects articular cartilage against cytokine-induced matrix degradation yet not have prolonged or permanent detrimental effects on chondrocyte matrix synthesis.