Expression of the cyclooxygenase isoforms in the prodromal stage of black walnut-induced laminitis in horses

Waguespack, Richard W.; Cochran, A.; Belknap, James K.

doi:10.2460/ajvr.2004.65.1724

Cited by 70 publications

(82 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…14 The primers used for COX-1, COX-2 and housekeeping genes (b-actin, b 2 microglobulin) also were identical to those previously reported.…”

Section: Real-time Quantitative Pcr (Rt-qpcr)mentioning

confidence: 93%

Cyclooxygenase Expression in The Early Stages of Equine Laminitis: A Cytologic Study

Blikslager¹,

Yin²,

Cochran³

et al. 2006

J Vet Int Med

Self Cite

View full text Add to dashboard Cite

Background: Recent reports indicate increased amounts of mRNA from inflammation-related genes in the prodromal stage of laminitis.Hypothesis: Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) undergo distinct patterns of expression in equine laminae in the developmental stage (DEV) and acute clinical stage (LAM) of laminitis.Animals: Horses selected from an outbred population were placed into 1 of 4 groups: DEV (n 5 5), CON-3h (control group for DEV, n 5 5), LAM (n 5 5) and CON-10h (control group for LAM, n 5 5).Methods: Laminar and skin samples were obtained from (1) animals either undergoing leukopenia (DEV) or the onset of clinical signs of laminitis (LAM) after black walnut extract (BWE) administration and (2) animals either 3 (CON-3h ) or 10 (CON-10h) hours after administration of water. Real-time quantitative polymerase chain reaction (RT-qPCR), immunoblotting, and immunohistochemical analysis were performed for COX-1 and COX-2.Results: Upon immunohistochemical analysis of all 4 groups, COX-2 was expressed by most viable epithelial cells in both laminae and skin. COX-1 exhibited similar epithelial expression to COX-2 in skin epidermis, but was expressed exclusively in the basal layer of laminar epidermis. COX-1 protein was not detectable in dermal vasculature of equine skin or laminae, whereas COX-2 was present in endothelial and vascular smooth muscle cells of dermal vasculature in both skin and laminae in all groups. A marked increase in laminar COX-2 protein concentrations was detected on immunoblotting in the DEV group, although a lesser increase was observed in the LAM group.Conclusions and Clinical Importance: COX-2 protein expression is markedly increased in the resident laminar cell types in the developmental stage of BWE-induced laminitis.

show abstract

“…14 The primers used for COX-1, COX-2 and housekeeping genes (b-actin, b 2 microglobulin) also were identical to those previously reported.…”

Section: Real-time Quantitative Pcr (Rt-qpcr)mentioning

confidence: 93%

Cyclooxygenase Expression in The Early Stages of Equine Laminitis: A Cytologic Study

Blikslager¹,

Yin²,

Cochran³

et al. 2006

J Vet Int Med

Self Cite

View full text Add to dashboard Cite

show abstract

“…Amplification was quantified against external standards using fluorescent format for SYBR Green I as previously described 21, 22. Primers for peroxisome proliferator‐activated receptor‐γ (PPARγ), peroxisome proliferator‐activated receptor‐γ coactivator 1‐α (PGC1α), AMPKα, phosphoenolpyruvate carboxykinase (PEPCK), and the housekeeping genes β‐actin and β 2 ‐microglobulin were designed against equine‐specific gene sequences (using exon sequence spanning an intron) using computer programs as previously described21, 23, 24; these primers subsequently were used for amplification of the respective genes of interest. Standard curves for quantification of mRNA concentration in laminar tissue samples were generated using serial dilutions of a linearized vector20 containing an insert of each amplified cDNA fragment (identity confirmed by nucleic acid sequencing).…”

Section: Methodsmentioning

confidence: 99%

Effect of Dietary Nonstructural Carbohydrate Content on Activation of 5′‐Adenosine Monophosphate‐Activated Protein Kinase in Liver, Skeletal Muscle, and Digital Laminae of Lean and Obese Ponies

Burns

Watts

Weber

et al. 2014

Veterinary Internal Medicne

View full text Add to dashboard Cite

BackgroundIn EMS‐associated laminitis, laminar failure may occur in response to energy failure related to insulin resistance (IR) or to the effect of hyperinsulinemia on laminar tissue. 5′‐Adenosine‐monophosphate‐activated protein kinase (AMPK) is a marker of tissue energy deprivation, which may occur in IR.Hypothesis/ObjectivesTo characterize tissue AMPK regulation in ponies subjected to a dietary carbohydrate (CHO) challenge.AnimalsTwenty‐two mixed‐breed ponies.MethodsImmunohistochemistry and immunoblotting for total AMPK and phospho(P)‐AMPK and RT‐qPCR for AMPK‐responsive genes were performed on laminar, liver, and skeletal muscle samples collected after a 7‐day feeding protocol in which ponies stratified on body condition score (BCS; obese or lean) were fed either a low‐CHO diet (ESC + starch, approximately 7% DM; n = 5 obese, 5 lean) or a high‐CHO diet (ESC + starch, approximately 42% DM; n = 6 obese, 6 lean).Results5′‐Adenosine‐monophosphate‐activated protein kinase was immunolocalized to laminar keratinocytes, dermal constituents, and hepatocytes. A high‐CHO diet resulted in significantly decreased laminar [P‐AMPK] in lean ponies (P = .03), but no changes in skeletal muscle (lean, P = .33; obese, P = .43) or liver (lean, P = .84; obese, P = .13) [P‐AMPK]. An inverse correlation existed between [blood glucose] and laminar [P‐AMPK] in obese ponies on a high‐CHO diet.Conclusions and Clinical ImportanceLaminar tissue exhibited a normal response to a high‐CHO diet (decreased [P‐AMPK]), whereas this response was not observed in liver and skeletal muscle in both lean (skeletal muscle, P = .33; liver, P = .84) and obese (skeletal muscle, P = .43; liver, P = .13) ponies.

show abstract

“…interleukin [IL]-1β, IL-6), cyclooxygenase (COX)-2, and matrix metalloproteinases (MMPs) in the digital laminae. [5][6][7][8][9] Locally released and activated MMPs mediate degradation of the collagen components of the basement membrane (BM) that is interposed between the secondary dermal (SDL) and epidermal lamellae (SEL) and cause a separation of the SEL from the BM. 4,[10][11][12][13][14] Sensory innervation of the foot consists of thick myelinated A-fibers (largely A β ) transmitting low-threshold mechanical information and small thin myelinated (A δ -fibers) and un-myelinated afferents (C-fibers) which express a variety of peptides and transmit high-threshold nociceptive information.…”

Section: Mechanisms Of Pain In Laminitismentioning

confidence: 99%

“…7,8 Unless resolving on their own histological changes at the dermal-epidermal interface progress further causing within 24-72 hours the BM to retract so much from SEL that SDL connective tissue and SDL capillaries are injured by tension and shear forces (grade 2 histological laminitis), 4 likely provoking activation of perivascular sensory nerve terminals near the base of the dermal lamellae.…”

Section: Mechanisms Of Pain In Laminitismentioning

confidence: 99%

Neuropathic Pain Management in Chronic Laminitis

Driessen

Bauquier

Zarucco

2010

Veterinary Clinics of North America: Equine Practice

View full text Add to dashboard Cite

Expression of the cyclooxygenase isoforms in the prodromal stage of black walnut-induced laminitis in horses

Cited by 70 publications

References 43 publications

Cyclooxygenase Expression in The Early Stages of Equine Laminitis: A Cytologic Study

Cyclooxygenase Expression in The Early Stages of Equine Laminitis: A Cytologic Study

Effect of Dietary Nonstructural Carbohydrate Content on Activation of 5′‐Adenosine Monophosphate‐Activated Protein Kinase in Liver, Skeletal Muscle, and Digital Laminae of Lean and Obese Ponies

Neuropathic Pain Management in Chronic Laminitis

Contact Info

Product

Resources

About