Methylprednisolone is a synthetic corticosteroid commonly used in veterinary medicine, including equine practice, to manage inflammation and immune-mediated conditions. It functions by suppressing the inflammatory response and modulating immune system activity, which can be beneficial in treating conditions such as arthritis, allergic reactions, and certain skin disorders in horses. Methylprednisolone is administered in various forms, including injections and oral formulations, depending on the specific condition being treated. The pharmacokinetics, efficacy, and potential side effects of methylprednisolone in horses are subjects of ongoing research. This page compiles peer-reviewed research studies and scholarly articles that explore the use, effects, and safety considerations of methylprednisolone in equine medicine.
Edmonds RE, Garvican ER, Smith RK, Dudhia J.To provide evidence to support recommendations regarding the co-administration of drugs with mesenchymal stem cell (MSC) therapy. Objective: To determine the influence of sedatives, local anaesthetic and corticosteroids on MSC viability and proliferation, in comparison to somatic cells derived from tendon (TDCs). Methods: In vitro cell culture. Methods: MSCs (n = 3) and TDCs (n = 2) were cultured in media containing a clinically relevant dose range of xylazine, romifidine, detomidine and butorphanol, mepivacaine, methylprednisolone, or triamcinolone acetonide. Cell viability in suspension cult...
Vandeweerd JM, Zhao Y, Nisolle JF, Zhang W, Zhihong L, Clegg P, Gustin P.Intra-articular (IA) corticosteroids (CS) have been used in the treatment of osteoarthritis for many years, although their effects on articular cartilage are not fully understood. To identify whether previous animal studies have provided enough evidence about the effects of CS, we undertook a systematic review that identified 35 relevant in vivo animal experimental studies between 1965 and 2014 assessing the effects of CS on either normal cartilage, or in either induced osteoarthritis (OA) or synovitis. The quality of the methodology was assessed. Deleterious effects, both structural and bioc...
Knych HK, Harrison LM, Casbeer HC, McKemie DS.Methylprednisolone acetate (MPA) is commonly administered to performance horses, and therefore, establishing appropriate withdrawal times prior to performance is critical. The objectives of this study were to describe the plasma pharmacokinetics of MPA and time-related urine and synovial fluid concentrations following intra-articular administration to sixteen racing fit adult Thoroughbred horses. Horses received a single intra-articular administration of MPA (100 mg). Blood, urine, and synovial fluid samples were collected prior to and at various times up to 77 days postdrug administration a...
Byron CR, Benson BM, Stewart AA, Pondenis HC.To evaluate the effects of methylprednisolone acetate (MPA) on proteoglycan production by equine chondrocytes and to investigate whether glucosamine hydrochloride modulates these effects at clinically relevant concentrations. Methods: Articular cartilage with normal gross appearance from metacarpophalangeal and metatarsophalangeal joints of 8 horses (1 to 10 years of age). Methods: In vitro chondrocyte pellets were pretreated with glucosamine (0, 1, 10, and 100 microg/mL) for 48 hours and exposed to MPA (0, 0.05, and 0.5 mg/mL) for 24 hours. Pellets and media were assayed for proteoglycan prod...
Labens R, Mellor DJ, Voûte LC.Osteoarthritis of the distal tarsal joints, affecting the centrodistal and tarsometatarsal joints, is a common cause of hindlimb lameness in horses. This paper describes the outcome of the intra-articular treatment of 51 horses with the condition with either methylprednisolone acetate (mpa) or triamcinolone acetonide (tr), either with or without hyaluronic acid (ha). The outcome was assessed in terms of the changes in the horses' grade of lameness. Follow-up information was obtained from the owners by means of a telephone questionnaire. Horses treated once with mpa or tr, either with or withou...
Kristiansen KK, Kold SE.There is limited knowledge available of factors influencing response to treatments of the DIP-joint in horses with lameness responding to diagnostic analgesia of the DIP-joint. For this reason a multivariable statistical analysis was performed. Objective: Horses with lameness reduced by > or = 75% 10 min after intra-articular analgesia of the DIP-joint, can be treated successfully by intra-articular medication of the joint. Multiple factors influence the response to treatment. Methods: The study was performed retrospectively based on clinical records of horses treated with either polysulpha...
Soma LR, Uboh CE, Luo Y, Guan F, Moate PJ, Boston RC.To determine the pharmacokinetics of methylprednisolone (MP) and develop a pharmacokinetic-pharmacodynamic model of the related changes in plasma concentrations of endogenous hydrocortisone (HYD) and cortisone (COR) following intra-articular administration of methylprednisolone acetate (MPA) in horses. Methods: 6 Thoroughbreds. Methods: In each horse, 200 mg of MPA was injected intrasynovially into a carpal joint, and plasma MP, HYD, and COR concentrations were determined via liquid chromatography-mass spectrometry. Results: A 5-compartment pharmacokinetic-pharmacodynamic model was used to des...
Doyle AJ, Stewart AA, Constable PD, Eurell JA, Freeman DE, Griffon DJ.To determine effects of sodium hyaluronate (HA) on corticosteroid-induced cartilage matrix catabolism in equine articular cartilage explants. Methods: 30 articular cartilage explants from fetlock joints of 5 adult horses without joint disease. Methods: Articular cartilage explants were treated with control medium or medium containing methylprednisolone acetate (MPA; 0.05, 0.5, or 5.0 mg/mL), HA (0.1, 1.0, or 1.5 mg/mL), or both. Proteoglycan (PG) synthesis was measured by incorporation of sulfur 35-labeled sodium sulphate into PGs, and PG degradation was measured by release of radiolabeled PGs...
Dechant JE, Baxter GM, Frisbie DD, Trotter GW, McIlwraith CW.Osteoarthritis is a frequent sequela of joint disease, especially with severe injuries or if attempts at therapy are unsuccessful. Negative and positive effects of corticosteroid treatment of articular cartilage have been demonstrated by in vitro and in vivo studies. Objective: To assess the metabolic effects of varying dosages of methylprednisolone acetate (MPA) and triamcinolone acetonide (TA) on interleukin-1alpha (IL-1) conditioned equine cartilage explants. Our hypothesis was that lower dosages of corticosteroids would be less detrimental to cartilage metabolism than higher dosages. TA wo...
Murphy DJ, Todhunter RJ, Fubini SL, Vernier-Singer M, Straubinger RK, Lust G.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). Methods: 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 effe...
Clegg PD, Jones MD, Carter SD.Loss of articular cartilage, which is the most important pathological lesion occurring in osteoarthritis, has been shown to be enzymatically mediated. The matrix metalloproteinases (MMPs) are a group of enzymes which have been implicated in this degradation of articular cartilage matrix. The use of pharmacological agents to inhibit this catabolic process in the joint is a potential route for therapeutic intervention. The gelatinase MMPs, MMPs-2 and 9, were purified by affinity chromatography from equine cell cultures. The ability of phenylbutazone, flunixin, betamethasone, dexamethasone, methy...
MacLeod JN, Fubini SL, Gu DN, Tetreault JW, Todhunter RJ.To determine whether steady-state levels of type-II procollagen, aggrecan core protein, or fibronectin mRNA in articular chondrocytes are altered by synovitis or administration of methylprednisolone acetate (MPA). Methods: Articular cartilage specimens collected from 10 ponies, 2.5 to 3.5 years old and 200 to 300 kg. Methods: 4 experimental groups were compared, using the cartilage specimens: control, MPA-treated, lipopolysaccharide-induced synovitis, and lipopolysaccharide-induced synovitis with MPA treatment. RNA was isolated from articular cartilage and compared by northern blot analysis, u...
Todhunter RJ, Fubini SL, Wootton JA, Lust G.The effect of different doses of methylprednisolone acetate (MPA) on proteoglycan and collagen metabolism of articular cartilage from normal equine joints was tested in vitro. Methods: Cultured explants were treated with 0, 0.0004, 0.004, 0.04, 0.4 and 4.0 mg/ml (approximately 10(-6)-10(-2) M) MPA for 72 h. Proteoglycan synthesis was measured by incorporation of sodium [35S]sulfate into proteoglycans and proteoglycan degradation was measured by release of total and radiolabeled proteoglycan into the culture media. The size of the proteoglycans was assessed with size exclusion chromatography un...
Carter BG, Bertone AL, Weisbrode SE, Bailey MQ, Andrews JM, Palmer JL.To evaluate joint function and healing of surgically created full-thickness articular cartilage defects in exercised horses after intra-articular administration of methylprednisolone acetate (MPA; 120 mg) and sterile saline solution in the contralateral limb. Methods: Experimental investigation. Methods: 12 healthy, sound, radiographically normal horses with induced full-thickness osteochondral lesions on the medial and lateral trochlear ridges of the tali. Methods: Two 8.4-mm-diameter full-thickness articular cartilage lesions were created in each tarsocrural joint (12 horses [24 tarsocrural ...
Saari H, Tulamo RM, Konttinen YT, Sorsa T.A high performance liquid chromatography (HPLC) procedure suitable for the simultaneous determination of the molecular size and concentration of macromolecular hyaluronate and proteoglycans in synovial fluid has been developed. Irrigation of the equine tarsocrural joint with 20 ml physiological saline (PSS) caused a mild inflammation with an increase of proteoglycans in the synovial fluid over the baseline arthrocentesis control sample. Proteoglycan and hyaluronate in the synovial fluid did not interact to form hyaluronate-proteoglycan aggregates, but separated as distinct chromatographic peak...
Autefage A, Alvinerie M, Toutain PL.Synovial fluid and plasma kinetics of methylprednisolone acetate (MPA) and methylprednisolone (MP) after a single intra-articular administration of MPA at a therapeutic dose (111 mg in toto) was measured in five horses. MPA was detected in synovial fluid for two to six days post injection and MP, which results from synovial MPA hydrolysis, was present in pharmacologically significant concentrations for 4.8 to 39 days, depending on the horse. MPA synovial concentration was maximal (289 +/- 284 micrograms/ml) at the first sampling time (2 h after administration) and MP synovial concentration was...
Gallicano KD, Ng RM, Young LM.Methylprednisolone and three metabolites, 17,21-dihydroxy-6 alpha-methyl-1,4-pregnadiene-3,11,20-trione, 6 alpha-methyl-17,20 beta,21-trihydroxy-1,4-pregnadiene-3,11-dione, and 6 alpha-methyl-11 beta,17,20 beta,21-tetrahydroxy-1,4-pregnadien-3-one were detected in equine urine after intraarticular administration of methylprednisolone acetate. All four compounds were excreted both in the unconjugated form and as glucuronic acid conjugates. They were identified by comparing data obtained from analyses by high performance liquid chromatography, thin-layer chromatography, ultraviolet spectroscopy ...
Dechant JE, Baxter GM, Frisbie DD, Trotter GW, McIlwraith CW.Osteoarthritis is a frequent sequela of joint disease, especially with severe injuries or if attempts at therapy are unsuccessful. Negative and positive effects of corticosteroid treatment of articular cartilage have been demonstrated by in vitro and in vivo studies. Objective: To assess the metabolic effects of varying dosages of methylprednisolone acetate (MPA) and triamcinolone acetonide (TA) on interleukin-1alpha (IL-1) conditioned equine cartilage explants. Our hypothesis was that lower dosages of corticosteroids would be less detrimental to cartilage metabolism than higher dosages. TA wo...
Vandeweerd JM, Zhao Y, Nisolle JF, Zhang W, Zhihong L, Clegg P, Gustin P.Intra-articular (IA) corticosteroids (CS) have been used in the treatment of osteoarthritis for many years, although their effects on articular cartilage are not fully understood. To identify whether previous animal studies have provided enough evidence about the effects of CS, we undertook a systematic review that identified 35 relevant in vivo animal experimental studies between 1965 and 2014 assessing the effects of CS on either normal cartilage, or in either induced osteoarthritis (OA) or synovitis. The quality of the methodology was assessed. Deleterious effects, both structural and bioc...
Byron CR, Benson BM, Stewart AA, Pondenis HC.To evaluate the effects of methylprednisolone acetate (MPA) on proteoglycan production by equine chondrocytes and to investigate whether glucosamine hydrochloride modulates these effects at clinically relevant concentrations. Methods: Articular cartilage with normal gross appearance from metacarpophalangeal and metatarsophalangeal joints of 8 horses (1 to 10 years of age). Methods: In vitro chondrocyte pellets were pretreated with glucosamine (0, 1, 10, and 100 microg/mL) for 48 hours and exposed to MPA (0, 0.05, and 0.5 mg/mL) for 24 hours. Pellets and media were assayed for proteoglycan prod...
Autefage A, Alvinerie M, Toutain PL.Synovial fluid and plasma kinetics of methylprednisolone acetate (MPA) and methylprednisolone (MP) after a single intra-articular administration of MPA at a therapeutic dose (111 mg in toto) was measured in five horses. MPA was detected in synovial fluid for two to six days post injection and MP, which results from synovial MPA hydrolysis, was present in pharmacologically significant concentrations for 4.8 to 39 days, depending on the horse. MPA synovial concentration was maximal (289 +/- 284 micrograms/ml) at the first sampling time (2 h after administration) and MP synovial concentration was...
Soma LR, Uboh CE, Luo Y, Guan F, Moate PJ, Boston RC.To determine the pharmacokinetics of methylprednisolone (MP) and develop a pharmacokinetic-pharmacodynamic model of the related changes in plasma concentrations of endogenous hydrocortisone (HYD) and cortisone (COR) following intra-articular administration of methylprednisolone acetate (MPA) in horses. Methods: 6 Thoroughbreds. Methods: In each horse, 200 mg of MPA was injected intrasynovially into a carpal joint, and plasma MP, HYD, and COR concentrations were determined via liquid chromatography-mass spectrometry. Results: A 5-compartment pharmacokinetic-pharmacodynamic model was used to des...
Carter BG, Bertone AL, Weisbrode SE, Bailey MQ, Andrews JM, Palmer JL.To evaluate joint function and healing of surgically created full-thickness articular cartilage defects in exercised horses after intra-articular administration of methylprednisolone acetate (MPA; 120 mg) and sterile saline solution in the contralateral limb. Methods: Experimental investigation. Methods: 12 healthy, sound, radiographically normal horses with induced full-thickness osteochondral lesions on the medial and lateral trochlear ridges of the tali. Methods: Two 8.4-mm-diameter full-thickness articular cartilage lesions were created in each tarsocrural joint (12 horses [24 tarsocrural ...
Labens R, Mellor DJ, Voûte LC.Osteoarthritis of the distal tarsal joints, affecting the centrodistal and tarsometatarsal joints, is a common cause of hindlimb lameness in horses. This paper describes the outcome of the intra-articular treatment of 51 horses with the condition with either methylprednisolone acetate (mpa) or triamcinolone acetonide (tr), either with or without hyaluronic acid (ha). The outcome was assessed in terms of the changes in the horses' grade of lameness. Follow-up information was obtained from the owners by means of a telephone questionnaire. Horses treated once with mpa or tr, either with or withou...
Knych HK, Harrison LM, Casbeer HC, McKemie DS.Methylprednisolone acetate (MPA) is commonly administered to performance horses, and therefore, establishing appropriate withdrawal times prior to performance is critical. The objectives of this study were to describe the plasma pharmacokinetics of MPA and time-related urine and synovial fluid concentrations following intra-articular administration to sixteen racing fit adult Thoroughbred horses. Horses received a single intra-articular administration of MPA (100 mg). Blood, urine, and synovial fluid samples were collected prior to and at various times up to 77 days postdrug administration a...
Murphy DJ, Todhunter RJ, Fubini SL, Vernier-Singer M, Straubinger RK, Lust G.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). Methods: 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 effe...
MacLeod JN, Fubini SL, Gu DN, Tetreault JW, Todhunter RJ.To determine whether steady-state levels of type-II procollagen, aggrecan core protein, or fibronectin mRNA in articular chondrocytes are altered by synovitis or administration of methylprednisolone acetate (MPA). Methods: Articular cartilage specimens collected from 10 ponies, 2.5 to 3.5 years old and 200 to 300 kg. Methods: 4 experimental groups were compared, using the cartilage specimens: control, MPA-treated, lipopolysaccharide-induced synovitis, and lipopolysaccharide-induced synovitis with MPA treatment. RNA was isolated from articular cartilage and compared by northern blot analysis, u...
Kristiansen KK, Kold SE.There is limited knowledge available of factors influencing response to treatments of the DIP-joint in horses with lameness responding to diagnostic analgesia of the DIP-joint. For this reason a multivariable statistical analysis was performed. Objective: Horses with lameness reduced by > or = 75% 10 min after intra-articular analgesia of the DIP-joint, can be treated successfully by intra-articular medication of the joint. Multiple factors influence the response to treatment. Methods: The study was performed retrospectively based on clinical records of horses treated with either polysulpha...
Todhunter RJ, Fubini SL, Wootton JA, Lust G.The effect of different doses of methylprednisolone acetate (MPA) on proteoglycan and collagen metabolism of articular cartilage from normal equine joints was tested in vitro. Methods: Cultured explants were treated with 0, 0.0004, 0.004, 0.04, 0.4 and 4.0 mg/ml (approximately 10(-6)-10(-2) M) MPA for 72 h. Proteoglycan synthesis was measured by incorporation of sodium [35S]sulfate into proteoglycans and proteoglycan degradation was measured by release of total and radiolabeled proteoglycan into the culture media. The size of the proteoglycans was assessed with size exclusion chromatography un...
Saari H, Tulamo RM, Konttinen YT, Sorsa T.A high performance liquid chromatography (HPLC) procedure suitable for the simultaneous determination of the molecular size and concentration of macromolecular hyaluronate and proteoglycans in synovial fluid has been developed. Irrigation of the equine tarsocrural joint with 20 ml physiological saline (PSS) caused a mild inflammation with an increase of proteoglycans in the synovial fluid over the baseline arthrocentesis control sample. Proteoglycan and hyaluronate in the synovial fluid did not interact to form hyaluronate-proteoglycan aggregates, but separated as distinct chromatographic peak...
Doyle AJ, Stewart AA, Constable PD, Eurell JA, Freeman DE, Griffon DJ.To determine effects of sodium hyaluronate (HA) on corticosteroid-induced cartilage matrix catabolism in equine articular cartilage explants. Methods: 30 articular cartilage explants from fetlock joints of 5 adult horses without joint disease. Methods: Articular cartilage explants were treated with control medium or medium containing methylprednisolone acetate (MPA; 0.05, 0.5, or 5.0 mg/mL), HA (0.1, 1.0, or 1.5 mg/mL), or both. Proteoglycan (PG) synthesis was measured by incorporation of sulfur 35-labeled sodium sulphate into PGs, and PG degradation was measured by release of radiolabeled PGs...
Clegg PD, Jones MD, Carter SD.Loss of articular cartilage, which is the most important pathological lesion occurring in osteoarthritis, has been shown to be enzymatically mediated. The matrix metalloproteinases (MMPs) are a group of enzymes which have been implicated in this degradation of articular cartilage matrix. The use of pharmacological agents to inhibit this catabolic process in the joint is a potential route for therapeutic intervention. The gelatinase MMPs, MMPs-2 and 9, were purified by affinity chromatography from equine cell cultures. The ability of phenylbutazone, flunixin, betamethasone, dexamethasone, methy...
Gallicano KD, Ng RM, Young LM.Methylprednisolone and three metabolites, 17,21-dihydroxy-6 alpha-methyl-1,4-pregnadiene-3,11,20-trione, 6 alpha-methyl-17,20 beta,21-trihydroxy-1,4-pregnadiene-3,11-dione, and 6 alpha-methyl-11 beta,17,20 beta,21-tetrahydroxy-1,4-pregnadien-3-one were detected in equine urine after intraarticular administration of methylprednisolone acetate. All four compounds were excreted both in the unconjugated form and as glucuronic acid conjugates. They were identified by comparing data obtained from analyses by high performance liquid chromatography, thin-layer chromatography, ultraviolet spectroscopy ...
Edmonds RE, Garvican ER, Smith RK, Dudhia J.To provide evidence to support recommendations regarding the co-administration of drugs with mesenchymal stem cell (MSC) therapy. Objective: To determine the influence of sedatives, local anaesthetic and corticosteroids on MSC viability and proliferation, in comparison to somatic cells derived from tendon (TDCs). Methods: In vitro cell culture. Methods: MSCs (n = 3) and TDCs (n = 2) were cultured in media containing a clinically relevant dose range of xylazine, romifidine, detomidine and butorphanol, mepivacaine, methylprednisolone, or triamcinolone acetonide. Cell viability in suspension cult...
