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Horner A, Bamford NJ, Stear MJ, Piedrafita D, Jabbar A, Hughes KJ, El-Hage CM, Preston S. Strongyle egg shedding and egg reappearance periods in horses with pituitary pars intermedia dysfunction. Vet Parasitol 2024; 328:110176. [PMID: 38603926 DOI: 10.1016/j.vetpar.2024.110176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/26/2024] [Accepted: 03/26/2024] [Indexed: 04/13/2024]
Abstract
Pituitary pars intermedia dysfunction (PPID) is the most common endocrine disorder of older horses. Immune dysfunction in horses with PPID could increase susceptibility to infectious diseases, including strongyle infections; however, few data are available. The aim of this study was to determine if horses with PPID had increased strongyle faecal egg counts (FEC) compared with control horses, over a fourteen-week period in Victoria, Australia. Clinical signs and plasma adrenocorticotropic hormone (ACTH) concentrations were used to categorise horses into PPID (n=14) or control (n=31) groups. Faecal samples were collected for FEC determination prior to anthelmintic treatment, and fortnightly post-treatment for each horse. Generalised linear mixed modelling, using a gamma distribution, was used to compare differences between groups in the repeated measures study. The confounding variable of age was controlled for as a fixed effect. Following anthelmintic treatment, mean FEC was greater for the PPID group compared to the control group on day 56 (405 ± 756 eggs per gram [EPG] vs 40 ± 85 EPG, p=0.05) and day 70 (753 ±1598 EPG vs 82 ±141 EPG, p=0.04). There were no differences in mean FEC between groups on days 84 and 98. Cumulative FEC (day 14 to day 98) was significantly greater for the PPID horses than control horses (2118 ± 4016 EPG vs 798 ± 768 EPG, p<0.0001). Group egg reappearance period was shorter for PPID horses (day 56 post-anthelmintic treatment) compared to control horses (day 70) and 30% of the PPID horses reached a FEC threshold of >200 EPG on day 42, compared to 0% of control horses (p=0.02). These results suggest that the rate of a re-established patent infection between groups could be different due to a comprised immune response in PPID horses or differences in the host-parasite relationship regarding encysted stage larvae. However, despite differences between groups, some horses with PPID consistently had no detectable or low FEC (<200 EPG) during the study period. These findings highlight the importance of individual FEC monitoring to determine if anthelmintic treatment is required, in line with sustainable parasite management practices.
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Affiliation(s)
- Adelaina Horner
- Institute of Innovation, Science and Sustainability, Federation University, Victoria 3350, Australia
| | - Nicholas J Bamford
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael J Stear
- School of Life Sciences, La Trobe University, Melbourne, Victoria 3086, Australia
| | - David Piedrafita
- Institute of Innovation, Science and Sustainability, Federation University, Victoria 3350, Australia
| | - Abdul Jabbar
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Kristopher J Hughes
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Charles M El-Hage
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Sarah Preston
- Institute of Innovation, Science and Sustainability, Federation University, Victoria 3350, Australia.
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2
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Zapf AM, Fey K, Büttner K, Gröf M, Staszyk C. Periodontal structures in horses with pituitary pars intermedia dysfunction: A histological evaluation. Front Vet Sci 2023; 10:1114445. [PMID: 36733635 PMCID: PMC9887139 DOI: 10.3389/fvets.2023.1114445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 01/02/2023] [Indexed: 01/18/2023] Open
Abstract
Introduction Pituitary pars intermedia dysfunction (PPID) and dental disorders are of major concern in horses older than 15 years. Although PPID in geriatric horses and dental disorders in all age groups are well described, a connection between this endocrine disease and pathological changes in equine dental structures has not yet been investigated. In humans, periodontitis is considered to be a complication of systemic diseases like diabetes mellitus type 2, obesity and various conditions leading to an impaired immune response. In PPID, cross links to insulin and immune dysregulations are proven. The aim of this study was to compare histological findings of the gingiva and the sub gingival periodontal ligament of PPID affected horses with control horses. Methods In a case-control morphometric descriptive study, 145 dental locations of 10 PPID affected horses (27.3 ± 2.06 years) were compared with 147 dental locations of 10 controls (21.4 ± 4.12 years). Histological parameters were leukocyte infiltration, keratinization of gingival epithelium, blood vessel supply of the periodontium and structure of cementum. Results The distribution and localization of gingival leukocyte infiltrations (LI) in PPID affected horses was more often multifocal to coalescing (p = 0.002) and reached into deeper parts of the periodontium, sometimes down to the sub gingival periodontal ligament (PDL). Aged animals of both groups showed higher prevalence (PPID: OR 1.66; controls: OR 1.15) for severe leukocyte infiltration in the PDL. PPID was not significantly associated with increased LI. The cementum bordering the soft tissue in interdental locations showed four times more irregularities in PPID affected horses than in controls which predisposes for interdental food impaction and periodontal diseases. Discussion In summary, multifocal to coalescing leukocytes and irregular cementum are seen more often in PPID than in controls - however our findings mainly reflect an association of older age with periodontal disease.
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Affiliation(s)
- Anne Maria Zapf
- Equine Clinic, Internal Medicine, Faculty of Veterinary Medicine, Justus-Liebig-University, Giessen, Germany,*Correspondence: Anne Maria Zapf ✉
| | - Kerstin Fey
- Equine Clinic, Internal Medicine, Faculty of Veterinary Medicine, Justus-Liebig-University, Giessen, Germany
| | - Kathrin Büttner
- Unit for Biomathematics and Data Processing, Faculty of Veterinary Medicine, Justus-Liebig-University, Giessen, Germany
| | - Manuela Gröf
- Faculty of Veterinary Medicine, Institute of Veterinary Pathology, Justus-Liebig-University, Giessen, Germany
| | - Carsten Staszyk
- Faculty of Veterinary Medicine, Institute of Veterinary-Anatomy, Histology, and Embryology, Justus-Liebig-University, Giessen, Germany
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DeNotta S, McFarlane D. Immunosenescence and inflammaging in the aged horse. Immun Ageing 2023; 20:2. [PMID: 36609345 PMCID: PMC9817422 DOI: 10.1186/s12979-022-00325-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/21/2022] [Indexed: 01/09/2023]
Abstract
The equine population in the United States and worldwide now includes a higher percentage of geriatric horses than ever previously recorded, and as methods to treat and manage elderly equids are developed and refined, this aging population will likely continue to expand. A better understanding of how horses age and the effect of age on immunity and disease susceptibility is needed to enable targeted preventative healthcare strategies for aged horses. This review article outlines the current state of knowledge regarding the effect of aging on immunity, vaccine responsiveness, and disease risk in the horse, highlighting similarities and differences to what is observed in aged humans. Horses show similar but milder age-related alterations in immune function to those reported in people. Decreases in lymphocyte proliferation and antibody production and diminished response to vaccination have all been documented in elderly horses, however, increased risk of infectious disease is not commonly reported. Aged horses also show evidence of a proinflammatory state (inflammaging) yet appear less susceptible to the chronic diseases of people for which inflammation is a risk factor. Information is currently lacking as to why the horse does not experience the same risk of age-related disease (e.g., cancer, heart disease, neurodegeneration) as people, although a lack of negative lifestyle habits, differences in diet, exercise, genetics and physiology may all contribute to improved health outcomes in the older horse.
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Affiliation(s)
- Sally DeNotta
- grid.15276.370000 0004 1936 8091Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL USA
| | - Dianne McFarlane
- grid.15276.370000 0004 1936 8091Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL USA
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4
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Kirkwood NC, Hughes KJ, Stewart AJ. Prospective Case Series of Clinical Signs and Adrenocorticotrophin (ACTH) Concentrations in Seven Horses Transitioning to Pituitary Pars Intermedia Dysfunction (PPID). Vet Sci 2022; 9:vetsci9100572. [PMID: 36288186 PMCID: PMC9607114 DOI: 10.3390/vetsci9100572] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/29/2022] [Accepted: 10/11/2022] [Indexed: 12/31/2022] Open
Abstract
Simple Summary Pituitary pars intermedia dysfunction (PPID) is a common disease of the geriatric horse population. The most common clinical sign of PPID is hypertrichosis, or a long hair-coat with delayed shedding. Hypertrichosis is the most easily recognized clinical sign of PPID. However, the presence of hypertrichosis is often associated with severe end-stage disease. There is little research investigating sub-clinical or early PPID and the clinical signs associated with these stages of disease. The benefit of being able to recognize early PPID, is that we are able to begin treatment earlier on in disease process, potentially reducing the deleterious consequences of PPID and improving survival. Laboratory tests are available to more accurately diagnose PPID, and these tests include the basal ACTH and TRH-stimulated ACTH tests. Basal ACTH is easy to perform and is recommended in cases where clinical disease is suspected. The TRH-stimulation test improves diagnostic accuracy in early PPID cases. This study documents both test results and clinical signs associated with the transition from subclinical to clinical PPID, so that we are better able to recognize potential early PPID, as well as interpret results in these horses. Abstract Poor recognition of subtle clinical abnormalities and equivocal ACTH concentrations make early diagnosis of PPID difficult. Progressive clinical findings and corresponding ACTH concentrations in horses transitioning to PPID over time have not been documented. Seven horses with ACTH concentrations equivocal for PPID (utilizing locally derived, seasonally adjusted diagnostic-cut off values (DCOV)) and no clinical signs of PPID were selected. Sequential measurement of basal and thyrotropin-releasing hormone (TRH)-stimulated ACTH concentrations and recording of clinical findings occurred from October 2017 to November 2021 in a prospective case series. In two horses, marked hypertrichosis developed. Although 1/11 basal ACTH concentrations were below DCOV in 2018, subsequently all basal ACTH concentrations in these two horses without treatment were greater than DCOV. One horse was treated with pergolide which normalized basal ACTH concentrations. Four horses developed intermittent, mild hypertrichosis, and one horse never developed hypertrichosis. Basal ACTH concentrations in these five horses were greater than DCOV in 63/133 (47.4%) of testing points. TRH-stimulated ACTH concentrations in these five horses were greater than DCOV in 77/133 (57.9%) of testing points, sometimes markedly increased and greater than the assay upper limit of detection (LoD) of 1250pg/mL. TRH-stimulated ACTH concentrations were most frequently positive in late summer and early autumn, with 24/37 (64.9%) of TRH-stimulated ACTH concentrations greater than the DCOV in February and March. Horses transitioning to PPID can have subtle clinical signs and equivocal ACTH concentrations. However, TRH-stimulated ACTH concentrations can be markedly greater than DCOV, especially in late summer and early autumn (February and March) allowing for identification of subclinical and transitional cases.
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Affiliation(s)
- Naomi C. Kirkwood
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Kristopher J. Hughes
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Allison J. Stewart
- School of Veterinary Science, Gatton Campus, The University of Queensland, Gatton, QLD 4343, Australia
- Correspondence: ; Tel.: +61-754-601-799
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Pituitary Pars Intermedia Dysfunction (PPID) in Horses. Vet Sci 2022; 9:vetsci9100556. [PMID: 36288169 PMCID: PMC9611634 DOI: 10.3390/vetsci9100556] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/25/2022] [Accepted: 10/04/2022] [Indexed: 12/12/2022] Open
Abstract
Substantial morbidity results from pituitary pars intermedia dysfunction (PPID) which is often underestimated by owners and veterinarians. Clinical signs, pathophysiology, diagnostic tests, and treatment protocols of this condition are reviewed. The importance of improved recognition of early clinical signs and diagnosis are highlighted, as initiation of treatment will result in improved quality of life. Future research should be targeted at improving the accuracy of the diagnosis of PPID, as basal adrenocorticotropic hormone (ACTH) concentration can lack sensitivity and thyrotropin releasing hormone (TRH) used to assess ACTH response to TRH stimulation is not commercially available as a sterile registered product in many countries. The relationship between PPID and insulin dysregulation and its association with laminitis, as well as additional management practices and long-term responses to treatment with pergolide also require further investigation.
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6
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Evaluation of peripheral blood polymorphonuclear cell functions after an oral carbohydrate overload in obese and insulin dysregulated horses. Vet Immunol Immunopathol 2022; 250:110455. [PMID: 35716440 DOI: 10.1016/j.vetimm.2022.110455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 05/11/2022] [Accepted: 06/08/2022] [Indexed: 11/20/2022]
Abstract
Obesity and insulin dysregulation (ID) are increasingly prevalent conditions in equid populations worldwide. Immune impairment is well described in humans with metabolic dysfunction and is reported but still incompletely understood in horses. This study evaluated the effect of acute induced transient hyperglycemia on apoptosis, phagocytosis and oxidative burst activity of peripheral blood polymorphonuclear cells (PMN) of lean and obese adult horses with or without insulin dysregulation. Seventeen adult horses were allocated into three groups based on their body condition score (BCS) and metabolic status: lean-insulin sensitive (lean-IS), obese-insulin sensitive (obese-IS) and obese-insulin dysregulated (obese-ID). ID was determined by insulin tolerance testing (ITT). Blood glucose elevation was induced through an infeed-oral glucose test (in-feed OGT), and all assessments of PMN functions (apoptosis, phagocytosis and oxidative burst) were done in vitro after isolation from peripheral blood before and 120 min after carbohydrate overload. Results were analyzed using a repeated measures linear mixed model with significance defined at P < 0.05. No differences in apoptosis were observed between experimental groups at any time point. Phagocytic capacity was significantly lower at baseline in the obese-ID group but increased in response to glucose administration when compared to the other two groups. Basal reactive oxygen species production in the obese-IS group differed significantly from the lean-IS and obese-ID groups and decreased significantly in response to glucose administration. Results from this study showed that both metabolic status itself, and oral glucose administration, seem to be factors that alter PMN functionality in horses, specifically phagocytosis and oxidative burst.
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Galinelli NC, Bailey SR, Bamford NJ, Harris PA. Nutritional considerations for the management of equine pituitary
pars intermedia
dysfunction. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- N. C. Galinelli
- Melbourne Veterinary School The University of Melbourne Parkville Victoria Australia
| | - S. R. Bailey
- Melbourne Veterinary School The University of Melbourne Parkville Victoria Australia
| | - N. J. Bamford
- Melbourne Veterinary School The University of Melbourne Parkville Victoria Australia
| | - P. A. Harris
- Equine Studies Group Waltham Petcare Science Institute Melton Mowbray UK
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Sage SE, Bedenice D, McKinney CA, Long AE, Pacheco A, Wagner B, Mazan MR, Paradis MR. Assessment of the impact of age and of blood-derived inflammatory markers in horses with colitis. J Vet Emerg Crit Care (San Antonio) 2021; 31:779-787. [PMID: 34432936 DOI: 10.1111/vec.13099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 02/07/2020] [Accepted: 03/02/2020] [Indexed: 12/30/2022]
Abstract
OBJECTIVES To determine the impact of age on survival in horses with colitis and to elucidate whether a lower type-1/type-2 cytokine ratio or an exaggerated inflammatory state contribute to reduced survival in aged horses. DESIGN Part 1: Retrospective cohort analysis. Part 2: Analytic observational study. ANIMALS Part 1: One hundred twenty-four adult horses with colitis. Part 2: Twenty-nine adult horses with new diarrhea onset while hospitalized. MEASUREMENTS AND MAIN RESULTS Part 1: Patient signalment, select clinicopathological data, diagnoses, treatment, hospitalization length, and invoice were compared between survivors (n = 101) and nonsurvivors (n = 23). Only age and plasma transfusion retained statistical significance in the final multivariate outcome model, with 8.5 times lower odds of survival in transfused horses (95% confidence interval [CI], 2.6-27.2%). Additionally, the likelihood of nonsurvival increased by 11.8% (95% CI, 4-20.2%) for every year the horse aged (P = 0.002). Similarly, geriatric horses (≥20 years) were 15.2 times more likely to die than young-adults (2-12 years, P = 0.03), independent of financial investment, documented comorbidities, and duration of hospitalization. Part 2: Select cytokine analyses were performed on serum collected from hospitalized horses within 1 hour of diarrhea onset (T0) and 6 hours later. At T0, all recorded clinicopathological variables were comparable between geriatric and young-adult horses, suggesting a similar degree of systemic illness. The median concentration of type-2 cytokines interleukin-4 and interleukin-10, and type-1 cytokine interferon-γ did not differ between age groups. Inflammatory cytokines interleukin-6 and tumor necrosis factor-α were significantly higher in geriatric compared to young-adult horses at both sampling time points. CONCLUSIONS Outcome of colitis was less favorable in aging horses and patients receiving a plasma transfusion. Although an exaggerated inflammatory state, based on increased interleukin-6 and tumor necrosis factor-α concentrations, in geriatric horses may contribute to reduced survival, a lower type-1/type-2 cytokines ratio was not identified in our geriatric population.
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Affiliation(s)
- Sophie E Sage
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Daniela Bedenice
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Caroline A McKinney
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Alicia E Long
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Ana Pacheco
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Bettina Wagner
- Department of Population Medicine and Diagnostic Sciences, Cornell University College of Veterinary Medicine, Ithaca, New York, USA
| | - Melissa R Mazan
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Mary Rose Paradis
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
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9
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Investigation of innate immune function in adult and geriatric horses. Vet Immunol Immunopathol 2021; 235:110207. [PMID: 33735821 DOI: 10.1016/j.vetimm.2021.110207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 01/25/2021] [Accepted: 02/07/2021] [Indexed: 11/23/2022]
Abstract
In order to better understand the influence of age on innate immune function in horses, blood was collected from twelve adult horses (aged 10-16 years; mean: 13 years) and ten geriatric horses (aged 18-26 years; mean: 21.7 years) for analysis of plasma myeloperoxidase, complete blood counts, and cytokine and receptor expression in response to in vitro stimulation with heat-inactivated Rhodococcus equi, heat-inactivated Escherichia coli, and PMA/ionomycin. Gene expression was measured using RT-PCR for IFNγ, IL-1β, IL-6, IL-8, IL-10, IL-12α, IL-13, IL-17α, TLR2, TLR4, and TNFα. Endocrine function and body weight were measured to assess any potential impacts of ACTH, insulin, or body weight on immune function; none of the horses had pituitary pars intermedia dysfunction. The geriatric horse group had lower concentrations of plasma myeloperoxidase (P = 0.0459) and lower absolute monocyte counts (P = 0.0477); however, the difference in monocyte counts was no longer significant after outliers were removed. Additionally, only two significant differences in cytokine/receptor expression in whole blood were observed. Compared with adult horses, the geriatric horses had increased TNFα expression after in vitro stimulation with heat-inactivated R. equi (P = 0.0224) and had decreased IL-17α expression after PMA/ionomycin stimulation when one outlier was excluded (P = 0.0334). These changes may represent a compensatory mechanism by which geriatric horses could ensure adequate immune responses despite potentially dysfunctional neutrophil activity and/or decreased monocyte counts. Aging may influence equine innate immune function, and additional research is warranted to confirm and further explore these findings.
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10
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Miller AB, Loynachan AT, Bush HM, Hart KA, Barker VD, Campana-Emard AG, Grubbs ST, Adams AA. Effects of pituitary pars intermedia dysfunction and Prascend (pergolide tablets) treatment on endocrine and immune function in horses. Domest Anim Endocrinol 2021; 74:106531. [PMID: 32942194 DOI: 10.1016/j.domaniend.2020.106531] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/19/2020] [Accepted: 07/24/2020] [Indexed: 11/24/2022]
Abstract
It remains unclear how pituitary pars intermedia dysfunction (PPID) and pergolide treatment (Prascend [pergolide tablets]) affect endocrine and immune function in horses. To evaluate these effects, blood was collected regularly from 28 university-owned horses (10 Non-PPID, 9 PPID control [PC], and 9 PPID treatment [PT]) over approximately 15 mo. Pergolide treatment was initiated after Day 0 collections. Analyses included ACTH, insulin, total cortisol, free cortisol, complete blood counts, plasma myeloperoxidase, and cytokine/receptor gene expression in basal whole blood and in vitro stimulations (PMA/ionomycin, heat-inactivated Rhodococcus equi, and heat-inactivated Escherichia coli) of whole blood and peripheral blood mononuclear cells (PBMCs). The results were analyzed using a linear mixed model (SAS 9.4) with significance set at P < 0.05. Significant group (P = 0.0014) and group-by-time (P = 0.0004) effects were observed in resting ACTH such that PT horses differed from Non-PPID horses only at Day 0. PT horses had significantly lower changes in ACTH responses to thyrotropin-releasing hormone stimulation tests than PC horses at non-fall time points only, mid-late February 2018 (P = 0.016) and early April 2018 (P = 0.0172). When PT and PC horses did not differ, they were combined before comparison to Non-PPID horses. No significant group or group-by-time effects were seen in resting insulin, total cortisol, or free cortisol; however, significant time effects were observed in these measures. PPID horses had lower absolute lymphocyte (P = 0.028) and red blood cell (P = 0.0203) counts than Non-PPID horses. In unstimulated whole blood, PPID horses had increased IL-8 expression compared with Non-PPID horses (P = 0.0102). In addition, PPID horses had decreased interferon γ production from PBMCs after stimulation with R. equi (P = 0.0063) and E. coli (P = 0.0057) and showed increased transforming growth factor β expression after E. coli stimulation (P = 0.0399). The main limitations of this study were a limited sample size and an inability to truly randomize the PPID horses into treatment groups. Resting ACTH is likely the best choice for determining successful responses to pergolide. Neither PPID nor pergolide appears to influence insulin, total cortisol, and free cortisol. As measured, systemic immune function was altered in PPID horses, and it is likely that these horses are indeed at increased risk of opportunistic infection. Despite reducing ACTH, pergolide treatment did not appear to influence immune function.
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Affiliation(s)
- A B Miller
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA.
| | - A T Loynachan
- Veterinary Diagnostic Laboratory, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - H M Bush
- Department of Biostatistics, University of Kentucky, Lexington, KY, USA
| | - K A Hart
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - V D Barker
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - A G Campana-Emard
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - S T Grubbs
- Boehringer Ingelheim Animal Health USA, Inc, Duluth, GA, USA
| | - A A Adams
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
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11
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Salinas C, Espinosa G, Morales N, Henríquez C, Morán G, Gajardo G, Uberti B. Assessment of peripheral blood neutrophil respiratory burst, phagocytosis and apoptosis in obese non-insulin dysregulated horses. Res Vet Sci 2020; 132:127-132. [PMID: 32563928 DOI: 10.1016/j.rvsc.2020.06.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 05/04/2020] [Accepted: 06/10/2020] [Indexed: 11/20/2022]
Abstract
Obesity is a highly prevalent condition in horses. Dysfunctional neutrophil activity has been reported in metabolically healthy obese humans, but minimal data exist regarding horses. The present study evaluated the effect of obesity on apoptosis, phagocytosis and oxidative burst activity of peripheral blood neutrophils from lean and obese non-insulin dysregulated horses. Seven lean (BCS, body condition score 4-6/9) and five obese (BCS 8-9) horses were enrolled in the study. All animals underwent two metabolic tests (OGT, oral glucose test; IRT, insulin response test) before their selection to ensure their metabolic status (non-insulin dysregulated). A single blood sample was obtained from each horse, and a discontinuous density gradient was carried out to isolate neutrophils. Phagocytosis, apoptosis and reactive oxygen species (ROS) production assays were performed for each animal. All statistical analyses were performed with unpaired two-tailed t-tests. Results indicate that neutrophils from obese non-insulin dysregulated horses have a significantly increased ROS production (P < .0001), with no changes observed on phagocytosis (P > .05) or apoptosis (P > .05) when compared to the control group. In conclusion, our results demonstrate that obesity per se, in absence of other endocrine disorders, alters neutrophil reactive oxygen species production. More research is needed to understand the role of obesity on the equine immune system of horses, and its role in the development of endocrine disorders.
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Affiliation(s)
- Constanza Salinas
- Escuela de Graduados, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile; Instituto de Ciencias Clínicas Veterinarias, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Gabriel Espinosa
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Natalia Morales
- Escuela de Graduados, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile; Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Claudio Henríquez
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Gabriel Morán
- Instituto de Farmacología y Morfofisiología, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Gonzalo Gajardo
- Escuela de Graduados, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Benjamin Uberti
- Instituto de Ciencias Clínicas Veterinarias, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
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12
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McFarlane D. Diagnostic Testing for Equine Endocrine Diseases: Confirmation Versus Confusion. Vet Clin North Am Equine Pract 2019; 35:327-338. [PMID: 31076223 DOI: 10.1016/j.cveq.2019.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Despite there being only 2 common endocrine diseases in horses, pituitary pars intermedia dysfunction (PPID) and equine metabolic syndrome (EMS), diagnosis is still confusing. Failing to consider horse factors and treating based on laboratory results only have caused many animals to receive lifelong drug treatment unnecessarily. Increased plasma ACTH, baseline or TRH stimulated, supports a diagnosis of PPID; however, breed, age, thriftiness, illness, coat color, geography, diet, and season also affect ACTH concentration. Insulin dysregulation, the hallmark of EMS, can result from insulin resistance or excessive postprandial insulin release. Each requires a different diagnostic test to reach a diagnosis.
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Affiliation(s)
- Dianne McFarlane
- Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, 264 McElroy Hall, CVHS-OSU, Stillwater, OK 74078, USA.
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Horn R, Bamford NJ, Afonso T, Sutherland M, Buckerfield J, Tan RHH, Secombe CJ, Stewart AJ, Bertin FR. Factors associated with survival, laminitis and insulin dysregulation in horses diagnosed with equine pituitary pars intermedia dysfunction. Equine Vet J 2018; 51:440-445. [DOI: 10.1111/evj.13041] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 11/02/2018] [Indexed: 12/29/2022]
Affiliation(s)
- R. Horn
- School of Veterinary Science The University of Queensland Gatton Queensland Australia
| | - N. J. Bamford
- Faculty of Veterinary and Agricultural Sciences The University of Melbourne Werribee Victoria Australia
| | - T. Afonso
- School of Animal and Veterinary Sciences The University of Adelaide Roseworthy South Australia Australia
| | - M. Sutherland
- Gisborne Veterinary Clinic Gisborne Victoria Australia
| | | | - R. H. H. Tan
- College of Public Health, Medical and Veterinary Sciences James Cook University Townsville Queensland Australia
- Samford Valley Veterinary Hospital Samford Queensland Australia
| | - C. J. Secombe
- School of Veterinary and Life Sciences Murdoch University Perth Western Australia Australia
| | - A. J. Stewart
- School of Veterinary Science The University of Queensland Gatton Queensland Australia
| | - F. R. Bertin
- School of Veterinary Science The University of Queensland Gatton Queensland Australia
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14
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Affiliation(s)
- C. J. Scott
- Rossdales Veterinary Surgeons Beaufort Cottage Stables Newmarket Suffolk UK
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15
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Vanderstock JM, Lecours MP, Lavoie-Lamoureux A, Gottschalk M, Segura M, Lavoie JP, Jean D. Phagocytosis, bacterial killing, and cytokine activation of circulating blood neutrophils in horses with severe equine asthma and control horses. Am J Vet Res 2018; 79:455-464. [PMID: 29583047 DOI: 10.2460/ajvr.79.4.455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate in vitro phagocytosis and bactericidal activity of circulating blood neutrophils in horses with severe equine asthma and control horses and to determine whether circulating blood neutrophils in horses with severe equine asthma have an increase in expression of the proinflammatory cytokine tumor necrosis factor (TNF)-α and the chemokine interleukin (IL)-8 and a decrease in expression of the anti-inflammatory cytokine IL-10 in response to bacteria. ANIMALS 6 horses with severe equine asthma and 6 control horses. PROCEDURES Circulating blood neutrophils were isolated from horses with severe equine asthma and control horses. Phagocytosis was evaluated by use of flow cytometry. Bactericidal activity of circulating blood neutrophils was assessed by use of Streptococcus equi and Streptococcus zooepidemicus as targets, whereas the cytokine mRNA response was assessed by use of a quantitative PCR assay. RESULTS Circulating blood neutrophils from horses with severe equine asthma had significantly lower bactericidal activity toward S zooepidemicus but not toward S equi, compared with results for control horses. Phagocytosis and mRNA expression of TNF-α, IL-8, and IL-10 were not different between groups. CONCLUSIONS AND CLINCAL RELEVANCE Impairment of bactericidal activity of circulating blood neutrophils in horses with severe equine asthma could contribute to an increased susceptibility to infections.
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Bullone M, Lavoie JP. The Contribution of Oxidative Stress and Inflamm-Aging in Human and Equine Asthma. Int J Mol Sci 2017; 18:ijms18122612. [PMID: 29206130 PMCID: PMC5751215 DOI: 10.3390/ijms18122612] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 11/27/2017] [Accepted: 11/29/2017] [Indexed: 02/07/2023] Open
Abstract
Aging is associated with a dysregulation of the immune system, leading to a general pro-inflammatory state of the organism, a process that has been named inflamm-aging. Oxidative stress has an important role in aging and in the regulation of immune responses, probably playing a role in the development of age-related diseases. The respiratory system function physiologically declines with the advancement of age. In elderly asthmatic patients, this may contribute to disease expression. In this review, we will focus on age-related changes affecting the immune system and in respiratory structure and function that could contribute to asthma occurrence, and/or clinical presentation in the elderly. Also, naturally occurring equine asthma will be discussed as a possible model for studying the importance of oxidative stress and immun-aging/inflamm-aging in humans.
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Affiliation(s)
- Michela Bullone
- Department of Clinical and Biological Sciences, University of Turin, AUO San Luigi Gonzaga, Regione Gonzole 10, 10043 Orbassano, Italy.
| | - Jean-Pierre Lavoie
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200 Rue Sicotte, St-Hyacinthe, QC J2S 2M2, Canada.
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17
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Sutton DGM, Michel AL. Mycobacterial infections in equids: Clinical characteristics and diagnostic techniques. EQUINE VET EDUC 2017. [DOI: 10.1111/eve.12839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- D. G. M. Sutton
- Weipers Centre Equine Hospital; School of Veterinary Medicine; College of Medical, Veterinary and Life Sciences; University of Glasgow; Glasgow UK
| | - A. L. Michel
- Bovine Tuberculosis and Brucellosis Research Programme; Department of Veterinary Tropical Disease; Faculty of Veterinary Science; University of Pretoria; Pretoria South Africa
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Abstract
The aging process in people is associated with changes in adaptive and innate immune responses. Similar changes occur in aged horses. Age-related progressive impairment in the ability to respond to pathogen challenge and an increased inflammatory reactivity may predispose geriatric horses to many diseases of old age. Specific recommendations for immune modification of older horses, including an age-appropriate vaccination schedule, are not currently available. In addition, the effect of old age on risk of infectious disease is poorly documented. More work is needed to better understand the interactions of age on immunity, vaccine response, and disease risk in horses.
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