Equine Metabolic Syndrome (EMS) is a condition in horses characterized by a combination of obesity, insulin resistance, and an increased risk of laminitis. This syndrome is often observed in horses with a predisposition to accumulate fat, particularly in specific areas such as the neck, shoulders, and tailhead. Insulin resistance in horses with EMS can lead to elevated insulin levels, which may contribute to the development of laminitis, a painful and potentially debilitating hoof condition. Research on EMS focuses on understanding its pathophysiology, identifying genetic and environmental risk factors, and developing management strategies to mitigate its effects. This page compiles peer-reviewed research studies and scholarly articles that explore the diagnosis, treatment, and management of Equine Metabolic Syndrome, as well as its implications for equine health and welfare.
Fitzgerald DM, Walsh DM, Sillence MN, Pollitt CC, de Laat MA.Supraphysiological insulin and incretin responses to a cereal-based diet have been described in horses and ponies with insulin dysregulation (ID). However, the hormonal responses to grazing have not yet been described. Objective: To determine if there is a difference in the insulin and incretin responses to grazing pasture between insulin-dysregulated and healthy ponies. Methods: A cohort of 16 ponies comprising 5 with normal insulin regulation (NIR), 6 with moderate ID (MID), and 5 with severe ID (SID). Methods: In this case-control study, an oral glucose test (OGT) was used to determine the ...
Durward-Akhurst SA, Schultz NE, Norton EM, Rendahl AK, Besselink H, Behnisch PA, Brouwer A, Geor RJ, Mickelson JR, McCue ME.Equine Metabolic Syndrome (EMS) is characterized by abnormalities in insulin regulation, increased adiposity and laminitis, and has several similarities to human metabolic syndrome. A large amount of environmental variability in the EMS phenotype is not explained by commonly measured factors (diet, exercise, and season), suggesting that other environmental factors play a role in EMS development. Endocrine disrupting chemicals (EDCs) are associated with metabolic syndrome and other endocrine abnormalities in humans. This led us to hypothesize that EDCs are detectable in horse plasma and play a ...
DeBoer ML, Hathaway MR, Weber PSD, Sheaffer CC, Kuhle KJ, Martinson KL.Spring and late fall grazing can lead to metabolic problems in horses (Equus caballus L.) as a result of elevated nonstructural carbohydrates (NSC) in pastures. Therefore, the objectives were to determine the impact of different forage species on blood glucose and insulin concentrations of horses during the spring and late fall. Research was conducted in May (spring) and October (late fall) in St. Paul, MN. Alfalfa (Medicago sativa L.) and mixed perennial cool-season grasses (CSG) were grazed in spring, and CSG and teff (Eragrostis tef [Zucc.] Trotter) were grazed in late fall by six adult hor...
Cárceles-RodrÃguez CM, Fernández-Varón E, MartÃn-Gimenez T, Aguirre C, Arion A, RodrÃguez MJ, Ayala I.Insulin dysregulation (ID) is a common metabolic disorder in horses. Recently, incretin hormone release has been suggested to be involved in ID in horses. In human medicine, metformin and sitagliptin are commonly used in combination for metabolic syndrome. This combination could be useful in treating ID in horses. However, no pharmacokinetics data have been reported in this species. The objective of the present study was to establish the plasma concentration-time profile and to derive pharmacokinetics data for a combination of metformin and sitagliptin in horses after enteral administration. S...
Kornicka K, Śmieszek A, Węgrzyn AS, Röcken M, Marycz K.Endocrine disorders, including equine metabolic syndrome (EMS), are a serious issue in veterinary medicine and horse breeding. Furthermore, EMS was shown to affect the cytophysiological properties of adipose-derived stem cells, reducing their therapeutic potential. However, it was shown that those cells can be rejuvenated while using a combination of two chemicals: 5-azacytydine (AZA) and resveratrol (RES). In the present study, we decided to evaluate the immunomodulatory properties of AZA/RES-treated adipose-derived stem cells (ASC) isolated from EMS horses (ASC). Thus, we co-cultured ASC wit...
Alicka M, Marycz K.Metabolic syndrome (MetS) is highly associated with a modern lifestyle. The prevalence of MetS has reached epidemic proportion and is still rising. The main cause of MetS and finally type 2 diabetes occurrence is excessive nutrient intake, lack of physical activity, and inflammatory cytokines secretion. These factors lead to redistribution of body fat and oxidative and endoplasmic reticulum (ER) stress occurrence, resulting in insulin resistance, increase adipocyte differentiation, and much elevated levels of proinflammatory cytokines. Cellular therapies, especially mesenchymal stem cell (MSC)...
Kornicka K, Śmieszek A, Szłapka-Kosarzewska J, Irwin Houston JM, Roecken M, Marycz K.Endocrine disorders are becoming an increasing problem in both human and veterinary medicine. In recent years, more and more horses worldwide have been suffering from equine metabolic syndrome (EMS). This metabolic disorder is characterized by pathological obesity, hyperinsulinaemia, hyperglycaemia and insulin resistance. Although metabolic disorders, including diabetes, have been extensively studied, there are still no data on the molecular effects of EMS in horses. Thus, the aim of this study was to evaluate apoptosis, oxidative stress, autophagy and microRNA (miR) expression in multipotent ...
Biddle AS, Tomb JF, Fan Z.Due to modern management practices and the availability of energy dense feeds, obesity is a serious and increasingly common health problem for horses. Equine obesity is linked to insulin resistance and exacerbation of inflammatory issues such as osteoarthritis and laminitis. While the gut microbiome is thought to play a part in metabolic status in horses, bacterial communities associated with obesity have yet to be described. Here we report differences in metabolic factors in the blood of obese, normal and lean horses correlated with differences in gut microbiome composition. We report that ob...
Mendoza FJ, Gonzalez-Cara CA, Aguilera-Aguilera R, Toribio RE, Perez-Ecija A.Metabolic disorders are highly prevalent in donkeys. Differences in energy regulatory hormones and glucose dynamic testing, including the intravenous glucose tolerance test (IVGTT) and combined glucose-insulin test (CGIT), have been documented between donkeys and horses. The aims of this study were to characterise the insulin:glucagon (IGR) and glucagon:insulin (GIR) molar ratios, at baseline and in response to the IVGTT and CGIT in healthy donkeys, and to determine their correlation with endocrine (leptin, ghrelin and adiponectin) and morphometric variables. Median values and interquartile ra...
Lewis SL, Holl HM, Long MT, Mallicote MF, Brooks SA.Equine metabolic syndrome (EMS), like human metabolic syndrome, comprises a collection of clinical signs related to obesity, insulin dysregulation and susceptibility to secondary inflammatory disease. Although the secondary conditions resulting from EMS can be life-threatening, diagnosis is not straightforward and often complicated by the presence of other concurrent conditions like pituitary pars intermedia dysfunction (PPID). In order to better characterize EMS, we sought to describe the variation within, and correlations between, typical physical and endocrine parameters for EMS. Utilizing ...
Marycz K, Kornicka K, Irwin-Houston JM, Weiss C.Endocrine disorders have become more and more frequently diagnosed in humans and animals. In horses, equine metabolic syndrome (EMS) is characterized by insulin resistance, hyperleptinemia, hyperinsulinemia, inflammation and usually by pathological obesity. Due to an increased inflammatory response in the adipose tissue, cytophysiological properties of adipose derived stem cells (ASC) have been impaired, which strongly limits their therapeutic potential. Excessive accumulation of reactive oxygen species, mitochondria deterioration and accelerated ageing of those cells affect their multipotency...
Marycz K, Weiss C, Åšmieszek A, Kornicka K.Mesenchymal stem cells (MSCs) are frequently used in both human and veterinary medicine because their unique properties, such as modulating the immune response and differentiating into multiple lineages, make them a valuable tool in cell-based therapies. However, many studies have indicated the age-, lifestyle-, and disease-related deterioration of MSC regenerative characteristics. However, it still needs to be elucidated how the patient's health status affects the effectiveness of MSC differentiation. In the present study, we isolated mesenchymal stem cells from adipose tissue (adipose-derive...
DeBoer ML, Hathaway MR, Kuhle KJ, Weber PSD, Reiter AS, Sheaffer CC, Wells MS, Martinson KL.Elevated nonstructural carbohydrate (NSC) values in pasture forages can cause adverse health effects in some horses (Equus caballus L.). The objectives of this study were to determine the impact of different forage species on blood glucose and insulin concentrations of horses throughout the grazing season. Research was conducted in July (summer) and September (fall) in St. Paul, MN. Alfalfa (Medicago sativa L.), mixed perennial cool-season grasses (CSG), and teff (Eragrostis tef [Zucc.] Trotter) pastures were grazed by six horses (24 ± 2 years) that were randomly assigned to one of three for...
Frank N.Equine athletes are affected by 2 major endocrine/metabolic disorders, insulin dysregulation (ID) and pituitary pars intermedia dysfunction. ID is a risk factor for laminitis in horses, which poses the greatest threat to performance because of the damage that it causes to hoof structures. This article includes an in-depth discussion of ID and other risk factors for laminitis that are grouped together as equine metabolic syndrome. As horses age, the risk of pituitary pars intermedia dysfunction increases, and this endocrine disorder may exacerbate preexisting ID and further increase the risk of...
Winter JC, Sponder G, Merle R, Aschenbach JR, Gehlen H.Equine metabolic syndrome (EMS) is a worldwide disease in horses that parallels human diabetes mellitus type 2. In both diseases, patients show an altered peripheral insulin sensitivity as a key feature. In humans, multiple studies have demonstrated the beneficial effect of magnesium supplementation on insulin sensitivity. However, serum magnesium levels vary and are therefore not a reliable indicator of the patients' magnesium status. Determining the intracellular free magnesium concentration appears to be a more sensitive diagnostic indicator. In this study, the free intracellular magnesium ...
Lindåse S, Müller C, Nostell K, Bröjer J.Information about the effect of nonstructural carbohydrates (NSCs) in forage on the postprandial glucose and insulin response in horses is scarce. This is of interest as postprandial hyperinsulinemia in horses is a risk factor for laminitis. In addition, insulin sensitivity (IS) differs between breeds. The aim was to evaluate the postprandial glucose and insulin response to haylage diets with different NSC content in horses of 2 different breeds and to evaluate the relationship between the postprandial insulin response and measures of IS derived from a frequently sampled intravenous glucose to...
Carslake HB, Argo CM, Pinchbeck GL, Dugdale AHA, McGowan CM.Reduction of the hyperinsulinaemic response to feeding is central to the management of insulin dysregulation (ID). The aim of this study was to compare insulinaemic and glycaemic responses to soaked hay, dry hay and haylage in ponies. Twelve ponies of mixed breeds were maintained under identical management conditions. A randomised four-way crossover trial was conducted, in which fasted animals were fed a meal of 0.25% body weight as dry matter intake soaked hay, dry hay or haylage, or administered an oral glucose test (OGT). Blood glucose and serum insulin concentrations were measured before a...
Elzinga S, Reedy S, Barker VD, Chambers TM, Adams AA.Obesity is an increasing problem in the equine population with recent reports indicating that the percentage of overweight horses may range anywhere from 20.6-51%. Obesity in horses has been linked to more serious health concerns such as equine metabolic syndrome (EMS). EMS is a serious problem in the equine industry given its defining characteristics of insulin dysregualtion and obesity, as well as the involvement of laminitis. Little research however has been conducted to determine the effects of EMS on routine healthcare of these horses, in particular how they respond to vaccination. It has...
Jacob SI, Murray KJ, Rendahl AK, Geor RJ, Schultz NE, McCue ME.Metabolomics, the study of small-molecule metabolites, has increased understanding of human metabolic diseases, but has not been used to study equine metabolic syndrome (EMS). Objective: (1) To examine the serum metabolome of Welsh Ponies with and without insulin dysregulation before and during an oral sugar test (OST). (2) To identify differences in metabolites in ponies with insulin dysregulation, obesity, or history of laminitis. Methods: Twenty Welsh Ponies (mean ± SD; 13.8 ± 9.0 years) classified as non-insulin dysregulated [CON] (n = 10, insulin  60 mU/L) at 75 minutes ...
Jocelyn NA, Harris PA, Menzies-Gow NJ.The oral sugar test (OST) is used to identify equine insulin dysregulation (ID); however only a dose of 0.15 mL/kg bwt corn syrup has been evaluated. Objective: To determine the effect of varying the dose of corn syrup on insulin and glucose response to the OST and the test's ability to distinguish between ponies with a history of laminitis (PL) and without laminitis (NL). Methods: Randomised crossover experiment. Methods: After an overnight fast, in a three-way randomised crossover study with a 7-day washout, 0.15, 0.3 or 0.45 mL/kg bwt corn syrup was administered orally to eight ponies (5 PL...
Jaqueth AL, Iwaniuk ME, Burk AO.It has been estimated in the United States and abroad that 20%-51% of the equine population suffers from over-conditioning or obesity. The objective of this study was to evaluate the prevalence of over-conditioning in the equine population in Maryland, to characterize weight control measures used, and to ascertain how control measures impact the operation. Over-conditioning was defined as a body condition score of 4 or 5 on a 5-point scale. All licensed horse operators in Maryland were invited to participate in an online survey. A total of 93 farm operators completed the survey with 238 ponies...
Rapson JL, Schott HC, Nielsen BD, McCutcheon LJ, Harris PA, Geor RJ.Age and diet may affect insulin sensitivity (SI) but these factors have received limited investigation in horses. Objective: To measure minimal model parameters during an insulin-modified frequently sampled intravenous glucose tolerance test (FSIGTT) after adaptation to a forage only diet (HAY) or forage supplemented with either starch/sugar-rich (SS) or oil/fibre-rich (FF) concentrate feeds; and to assess glucose and insulin responses to a standardised meal challenge (SMC, 4Â g/kg BW of SS) after diet adaptation in adult and aged mares. Methods: Latin square design with eight adult (5-12Â yea...
Marycz K, Michalak I, Kornicka K.Horses metabolic disorders have become an important problem of modern veterinary medicine. Pathological obesity, insulin resistance and predisposition toward laminitis are associated with Equine Metabolic Syndrome (EMS). Based on pathogenesis of EMS, dietary and cell therapy management may significantly reduce development of this disorder. Special attention has been paid to the diet supplementation with highly bioavailable minerals and mesenchymal stem cells (MSC) which increase insulin sensitivity. In nutrition, there is a great interests in natural algae enriched via biosorption process with...
Szydlarska J, Weiss C, Marycz K.Methyl-β-cyclodextrin (MβCD) is a cyclic oligosaccharide, commonly used as a pharmacological agent to deplete membrane cholesterol. In this study, we examined the effect of MβCD on adipose-derived mesenchymal stromal cells (ASCs) isolated form healthy horses (ASC) and from horses suffering from metabolic syndrome (ASC). We investigated the changes in the mRNA levels of the glucose transporter 4 (GLUT4) and found that MβCD application may lead to a significant improvement in glucose transport in ASC. We also showed that MβCD treatment affected GLUT4 upregulation in an insulin-independent m...
Kheder MH, Bailey SR, Dudley KJ, Sillence MN, de Laat MA.Equine metabolic syndrome (EMS) is associated with insulin dysregulation, which often manifests as post-prandial hyperinsulinemia. Circulating concentrations of the incretin hormone, glucagon-like peptide-1 (GLP-1) correlate with an increased insulin response to carbohydrate intake in animals with EMS. However, little is known about the equine GLP-1 receptor (eGLP-1R), or whether GLP-1 concentrations can be manipulated. The objectives were to determine (1) the tissue localisation of the eGLP-1R, (2) the GLP-1 secretory capacity of equine intestine in response to glucose and (3) whether GLP-1 s...
Warnken T, Delarocque J, Schumacher S, Huber K, Feige K.Insulin dysregulation (ID) with basal or postprandial hyperinsulinemia is one of the key findings in horses and ponies suffering from the equine metabolic syndrome (EMS). Assessment of ID can easily be performed in clinical settings by the use of oral glucose challenge tests. Oral glucose test (OGT) performed with 1Â g/kg bodyweight (BW) glucose administered via naso-gastric tube allows the exact administration of a defined glucose dosage in a short time. However, reliable cut-off values have not been available so far. Therefore, the aim of the study was to describe variations in insulin respo...
Marycz K, Kornicka K, Szlapka-Kosarzewska J, Weiss C.Nowadays, endocrine disorders have become more frequent in both human and veterinary medicine. In horses, reduced physical activity combined with carbohydrate and sugar overload may result in the development of the so-called equine metabolic syndrome (EMS). EMS is characterized by insulin resistance, hyperinsulinemia, elevated blood triglyceride concentrations and usually obesity. Although the phenotypic features of EMS individuals are well known, the molecular mechanism underlying disease development remains elusive. Therefore, in the present study, we analyzed insulin-sensitive tissues, i.e....
Marycz K, Michalak I, Kocherova I, Marędziak M, Weiss C.This study investigated in vitro effects of freshwater alga water extract enriched during a biosorption process in Cr(III) trivalent chromium and chromium picolinate on adipose-derived mesenchymal stromal stem cells (ASCs) and extracellular microvesicles (MVs) in equine metabolic syndrome-affected horses. Chemical characterisation of natural was performed with special emphasis on: vitamin C, vitamin E, total phenols, fatty acids, free and protein-bound amino acids as well as measured Cr in algal biomass. To examine the influence of water extracts, in vitro viability, oxidative stress factor...
Auyyuenyong R, Henze A, Ungru J, Schweigert FJ, Raila J, Vervuert I.Obesity is a key component of equine metabolic syndrome, which is highly associated with laminitis. Feed restriction and/or exercise are known to alleviate the detrimental effects of insulin resistance in obese ponies. However, little is known about changes in the serum lipid patterns due to weight reduction and its association with disease outcomes. Therefore, the lipid patterns in the serum of 14 mature ponies before and after a 14-week body weight reduction program (BWRP) were investigated by multi-one-dimensional thin-layer chromatography (MOD-TLC). Additionally, sensitivity to insulin (SI...
Cantarelli C, Dau SL, Stefanello S, Azevedo MS, De Bastiani GR, Palma HE, Brass KE, De La Côrte FD.Owing to the high prevalence of obesity in Crioulo horses, information allowing early diagnosis of equine metabolic syndrome (EMS) and prevention of the associated laminitis is of great value. The aim of this study was to evaluate the occurrence of EMS and the response to an oral sugar test (OST) in obese Crioulo horses. Twenty-two Crioulo horses were allocated into 3 groups according to their body condition score (BCS out of 9) and presence or absence of laminitis as follows: CON (6/22), BCS < 7; OB (8/22), BCS ≥ 7; and LAM (8/22), BCS ≥7 with clinical and/or radiographic signs of lam...
Fowden AL, Silver M, Ellis L, Ousey J, Rossdale PD.The factors influencing beta cell function in the foetal and neonatal foal have been investigated in chronically catheterised foetal foals and in newborn foals delivered either spontaneously at term or by induction at different gestational ages. Insulin was detected in the foetal plasma from as early as 150 days of gestation (term = 340 days) and during the last third of gestation the foetal beta cells responded to exogenous administration of glucose and arginine and to endogenous variations in the glucose level. Insulin secretion by the foetal beta cells was depressed by anaesthesia and surge...
Dosi MCM, Kirton R, Hallsworth S, Keen JA, Morgan RA.Obesity is a growing problem in UK equine population. Achieving weight loss in obese horses and ponies at risk of laminitis is an important but often challenging objective. Methods: We hypothesised that supplementing poor winter pasture with a mix of barley straw and hay (50:50) rather than hay alone (group B) would lead to weight loss in grazing equids over winter. For this purpose, a group of 40 horses were fed either the straw mix (group A) or hay alone (group B) over winter. Results: Over the study period, all animals in group A (n=25) lost weight with a mean weight change of -27±17 kg,...
Wearn JM, Crisman MV, Davis JL, Geor RJ, Hodgson DR, Suagee JK, Ashraf-Khorassani M, McCutcheon LJ.Pioglitazone is a thiazolidinedione class of antidiabetic agent with proven efficacy in increasing insulin sensitivity in humans with noninsulin-dependent diabetes mellitus, a syndrome of insulin resistance sharing similarities with equine metabolic syndrome. The purpose of this study was to determine the pharmacokinetics of pioglitazone in adult horses following multiple oral dose administration. Pioglitazone hydrochloride (1 mg/kg) was administered orally for 11 doses at 24-h intervals, and plasma samples were collected. Initially, a pilot study was performed using one horse; and thereafter ...
Van Weyenberg S, Buyse J, Kalmar ID, Swennen Q, Janssens GP.The relation between plasma leptin and daily ad libitum roughage intake was evaluated during a 14-day period in eight obese Shetland ponies. When the feeding strategy was changed from maintenance feeding to ad libitum feeding, feed intake increased the first day, decreased the second day and increased again during the following days to reach a constant level after 8 days. Plasma leptin concentration increased during the first 2 days, but remained constant afterwards. Although the same pattern was found in all ponies, the magnitude of the increase in leptin on day 1 and the resulting decrease i...
Serwotka-Suszczak AM, Marcinkowska KA, Smieszek A, Michalak IM, Grzebyk M, Wiśniewski M, Marycz KM.Insulin resistance (IR) is one of the characteristic features of equine metabolic syndrome (EMS). Presently, the only therapies of choice are caloric restrictions combined with mineral supplementation, which might improve insulin sensitivity. In this study we investigated the effect of Haematococcus pluvialis algae water extract enriched in bioaccumulation process in magnesium ions (Hp_Mg(II)) on equine adipose derived mesenchymal stromal stem cells, in which insulin resistance was induced by palmitic acid (IR-EqASCs). For this purpose, chemical characterization of H. pluvialis was performed w...
Lewis SL, Holl HM, Long MT, Mallicote MF, Brooks SA.Equine metabolic syndrome (EMS), like human metabolic syndrome, comprises a collection of clinical signs related to obesity, insulin dysregulation and susceptibility to secondary inflammatory disease. Although the secondary conditions resulting from EMS can be life-threatening, diagnosis is not straightforward and often complicated by the presence of other concurrent conditions like pituitary pars intermedia dysfunction (PPID). In order to better characterize EMS, we sought to describe the variation within, and correlations between, typical physical and endocrine parameters for EMS. Utilizing ...
Leschke DH, Muir GS, Hodgson JK, Coyle M, Horn R, Bertin FR.Diseases associated with insulin dysregulation (ID), such as equine metabolic syndrome and pituitary pars intermedia dysfunction, are of interest to practitioners because of their association with laminitis. Accurate insulin concentration assessment is critical in diagnosing and managing these diseases. Objective: To determine the effect of time, temperature, and collection tube type on insulin concentrations in horses at risk of ID. Methods: Eight adult horses with body condition score >6/9. Methods: In this prospective study, subjects underwent an infeed oral glucose test 2 hours before...
Bourebaba L, Zyzak M, Sikora M, Serwotka-Suszczak A, Mularczyk M, Al Naem M, Marycz K.Sex hormone binding globulin (SHBG) deteriorated expression has been recently strongly correlated to increased level of circulating pro-inflammatory cytokines and insulin resistance, which are typical manifestations of equine metabolic syndrome (EMS). Despite previous reports demonstrated the potential therapeutic application of SHBG for liver-related dysfunctions, whether SHBG might modulate equine adipose-derived stem/stromal cells (EqASCs) metabolic machinery remains unknown. Therefore, we evaluated for the first time the impact of SHBG protein on metabolic changes in ASCs isolated from hea...
Lindåse S, Müller C, Nostell K, Bröjer J.Information about the effect of nonstructural carbohydrates (NSCs) in forage on the postprandial glucose and insulin response in horses is scarce. This is of interest as postprandial hyperinsulinemia in horses is a risk factor for laminitis. In addition, insulin sensitivity (IS) differs between breeds. The aim was to evaluate the postprandial glucose and insulin response to haylage diets with different NSC content in horses of 2 different breeds and to evaluate the relationship between the postprandial insulin response and measures of IS derived from a frequently sampled intravenous glucose to...
Burns TA.Endocrine diseases, such as equine metabolic syndrome and pituitary pars intermedia dysfunction, are common in domesticated horse populations, and the frequency with which these diseases are encountered and managed by equine veterinary practitioners is expected to increase as the population ages. As clinicians learn more about the effects of these diseases on equine reproductive physiology and efficiency (including effects on reproductive seasonality, ovulation efficiency, implantation, early pregnancy loss, duration of pregnancy, and lactation), strategies and guidelines for improving fertili...
Zeyner A, Harmeyer J.L-carnitine, a betaine derivative of beta-hydroxybutyrate, is found in virtually all cells of higher animals and also in some microorganisms and plants. In animals it is synthesized almost exclusively in the liver. Two essential amino acids, i.e., lysine and methionine serve as primary substrates for its biosynthesis. Also required for its synthesis are sufficient amounts of vitamin B6, nicotinic acids, vitamin C and folate. The first discovered ergogenic function of L-carnitine is the transfer of activated long-chain fatty acids across the inner mitochondrial membrane into the mitochondrial m...
Nostell K, Lindåse S, Edberg H, Bröjer J.There is little evidence that horses with equine metabolic syndrome (EMS) have higher resting blood pressures than horses with normal insulin sensitivity. However, there are indications that EMS horses have an altered dynamic response to the cardiovascular effects of insulin. Objective: To examine heart rate and the systemic blood pressure response in EMS and control horses during insulin infusion. Methods: Cross-sectional study. Methods: Horses were examined with an oral sugar test (OST) and a euglycaemic hyperinsulinaemic clamp (EHC). Based on the results from the OST, the horses were classi...
de Graaf-Roelfsema E.One of the principal components of equine metabolic syndrome (EMS) is hyperinsulinaemia combined with insulin resistance. It has long been known that hyperinsulinaemia occurs after the development of insulin resistance. But it is also known that hyperinsulinaemia itself can induce insulin resistance and obesity and might play a key role in the development of metabolic syndrome. This review focuses on the physiology of glucose and insulin metabolism and the pathophysiological mechanisms in glucose homeostasis in the horse (compared with what is already known in humans) in order to gain insight ...
Dosi MCMC, McGorum BC, Kirton RD, Cillán-GarcÃa E, Mellanby RJ, Keen JA, Hurst EA, Morgan RA.Vitamin D deficiency is common in humans and is increasingly linked to the pathogenesis of a multitude of diseases including obesity and metabolic syndrome. The biology of vitamin D in horses is poorly described; the relative contribution of the diet and skin synthesis to circulating concentrations is unclear and associations with the endocrine disease have not been explored. Objective: To determine the relationship between management, season and endocrine disease and vitamin D status in horses. Methods: Cross-sectional cohort study. Methods: Plasma concentrations of 25-hydroxyvitamin D2 (25(O...
Manfredi JM, Stapley ED, Nadeau JA, Nash D.High insulin concentrations are a common clinical feature of equine metabolic syndrome (EMS) and insulin dysregulation. Hyperinsulinemia can induce laminitis, so reduction of insulin concentrations in response to an oral challenge should decrease risk. In human studies, diets containing a polyphenol (resveratrol) led to improvements in insulin sensitivity. In rodents, the addition of leucine to a resveratrol supplement caused a decrease in the amount of resveratrol needed to achieve a clinical effect. We hypothesize a supplementation with a low dose of a synergistic polyphenol and amino acid b...
Fleurance G, Duncan P, Fritz H, Gordon IJ, Grenier-Loustalot MF.The spatial heterogeneity of grasslands determines the abundance and quality of food resources for grazing animals. As plants mature, they increase in mass, which allows greater instantaneous intake rates, but the cell wall concentrations increase too, reducing diet quality. In ruminants, daily intake rates are often constrained by the time needed for the ingesta to pass through the rumen, which is influenced by the rate of digestion. It has been suggested that the digestive constraint should have much less effect on hindgut fermenters such as equids. Horses play an increasing role in the mana...
Szydlarska J, Weiss C, Marycz K.Methyl-β-cyclodextrin (MβCD) is a cyclic oligosaccharide, commonly used as a pharmacological agent to deplete membrane cholesterol. In this study, we examined the effect of MβCD on adipose-derived mesenchymal stromal cells (ASCs) isolated form healthy horses (ASC) and from horses suffering from metabolic syndrome (ASC). We investigated the changes in the mRNA levels of the glucose transporter 4 (GLUT4) and found that MβCD application may lead to a significant improvement in glucose transport in ASC. We also showed that MβCD treatment affected GLUT4 upregulation in an insulin-independent m...
Watts MR, Hegedus OC, Eades SC, Belknap JK, Burns TA.Hyperinsulinemia is associated with equine laminitis, and digital lamellar inflammation in equine metabolic syndrome-associated laminitis (EMSAL) is modest when compared with sepsis-associated laminitis. Objective: To characterize digital lamellar inflammation in horses in a euglycemic-hyperinsulinemic clamp (EHC) model of laminitis. Methods: Sixteen healthy adult Standardbred horses. Methods: Prospective experimental study. Horses underwent EHC or saline infusion (CON) for 48 hours or until the onset of Obel grade 1 laminitis. Horses were euthanized, and digital lamellar tissue was collecte...
Elzinga SE, Rohleder B, Schanbacher B, McQuerry K, Barker VD, Adams AA.Extracts derived from the leaves of the stevia plant (stevioside) are commonly used as sweeteners for humans and horses. Stevioside appears to be safe for human consumption, including for individuals with insulin dysregulation. In the horse, the safety or metabolic effects of stevioside on normal animals or on those with metabolic dysfunction are unknown. Furthermore, the inflammatory response to a glycemic challenge or to stevioside in horses is not well defined. Therefore, the objective of this study was to measure the effects of stevioside and a glycemic challenge on insulin, glucose, and i...
Cash CM, Fitzgerald DM, Spence RJ, de Laat MA.Equine metabolic syndrome (EMS) describes a group of risk factors, including obesity and insulin dysregulation (hyperinsulinemia and/or insulin resistance), that can lead to the development of the debilitating hoof disease laminitis. Although the underlying mechanisms of EMS are not fully understood, a genetic component has been reported, and an 11 guanine polymorphism located at the FAM174A gene has been identified as a risk locus for the syndrome in Arabian horses. To examine associations between the FAM174A risk allele and the clinical signs of EMS, the allele was examined in an Australian ...
Richards N, Nielsen BD, Finno CJ.Many forage types are available, typically divided into cool or warm season grasses and legumes, which can be fed as fresh pasture or after preservation. Testing for nutrient content confirms what should be supplemented to make up shortfalls. Although testing is recommended, it is not always practical. Typical values for the forage type are available; however, they cannot be relied on for actual content. Non-nutritional aspects must also be taken into account. The provision of complementary feeds to ensure adequate vitamin and mineral intake is recommended. Additional supplementary high-qualit...
Lovett AL, Gilliam LL, Sykes BW, McFarlane D.Both obesity and metabolic syndrome are associated with hypercoagulability in people, increasing the risk of cardiovascular disease and thromboembolic events. Whether hypercoagulability exists in obese, insulin-dysregulated horses is unknown. Objective: To determine if coagulation profiles differ between healthy horses and those with obesity and insulin dysregulation. Methods: Fifteen healthy horses (CON) and 15 obese, insulin-dysregulated horses (OBID). Individuals were university or client owned. Methods: Case-control study. Obesity was defined as a body condition score (BCS) ≥7.5/9 (modif...
Fuentes-Romero B, Muñoz-Prieto A, Cerón JJ, MartÃn-Cuervo M, Iglesias-GarcÃa M, Aguilera-Tejero E, DÃez-Castro E.Obesity and its associated complications, such as metabolic syndrome, are an increasing problem in both humans and horses in the developed world. The expression patterns of resistin differ considerably between species. In rodents, resistin is expressed by adipocytes and is related to obesity and ID. In humans, resistin is predominantly produced by inflammatory cells, and resistin concentrations do not reflect the degree of obesity, although they may predict cardiovascular outcomes. The aim of this study was to investigate the usefulness of resistin and its relationship with ID and selected ind...
Cantarelli C, Dau SL, Stefanello S, Azevedo MS, De Bastiani GR, Palma HE, Brass KE, De La Côrte FD.Owing to the high prevalence of obesity in Crioulo horses, information allowing early diagnosis of equine metabolic syndrome (EMS) and prevention of the associated laminitis is of great value. The aim of this study was to evaluate the occurrence of EMS and the response to an oral sugar test (OST) in obese Crioulo horses. Twenty-two Crioulo horses were allocated into 3 groups according to their body condition score (BCS out of 9) and presence or absence of laminitis as follows: CON (6/22), BCS < 7; OB (8/22), BCS ≥ 7; and LAM (8/22), BCS ≥7 with clinical and/or radiographic signs of lam...
Marycz K, Bourebaba N, Serwotka-Suszczak A, Mularczyk M, Galuppo L, Bourebaba L.Equine metabolic syndrome (EMS) is recognized as one of the leading cause of health threatening in veterinary medicine worldwide. Recently, PTP1B inhibition has been proposed as an interesting strategy for liver insulin resistance reversion in both equines and humans, however as being a multifactorial disease, proper management of EMS horses further necessities additional interventional approaches aiming at repairing and restoring liver functions. In this study, we hypothesized that in vitro induction of Eq_ASCs hepatogenic differentiation will generate a specialized liver progenitor-like cell...
Tadros EM, Frank N, De Witte FG, Boston RC.To test the hypothesis that glucose and insulin dynamics during endotoxemia differ between healthy horses and horses with equine metabolic syndrome (EMS). Methods: 6 healthy adult mares and 6 horses with EMS. Methods: Each horse randomly received an IV infusion of lipopolysaccharide (20 ng/kg [in 60 mL of sterile saline {0.9% NaCl} solution]) or saline solution, followed by the other treatment after a 7-day washout period. Baseline insulin-modified frequently sampled IV glucose tolerance tests were performed 27 hours before and then repeated at 0.5 and 21 hours after infusion. Results were ass...
