Analyze Diet

Topic:Biochemistry

The study of biochemistry in horses encompasses the chemical processes and substances that occur within equine organisms. This field investigates the molecular interactions and pathways that are fundamental to horse physiology, including metabolism, enzyme activity, and genetic expression. Key areas of interest include the examination of metabolic disorders, nutrient absorption, and the biochemical basis of muscle function and energy production. Researchers utilize biochemical analysis to understand health and disease mechanisms in horses, contributing to the development of diagnostic tools and therapeutic strategies. This page gathers peer-reviewed studies and scholarly articles that explore various biochemical processes and their implications for equine health and performance.
Cardiac Biomarker Responses to Acute Exercise in Show Jumping Horses.
Journal of equine veterinary science    July 6, 2023   Volume 128 104882 doi: 10.1016/j.jevs.2023.104882
Fazio F, Aragona F, Piccione G, Pino C, Giannetto C.Cardiac biomarkers are useful to identify cardiac muscle variations in human and equine medicine. The aim of this study was to investigate the acute effect of a bout of show jumping training on serum activity of cardiac and muscular biomarkers in healthy athletic horses to include cardiac troponin (cTnI), myoglobin (MB), aspartate amino transferase (AST), alanine amino transferase (ALT), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH). Serum samples were collected from seven Italian Saddle horses (three geldings and four mares; 10 ± 3 years; mean body weight 480 ±70 kg), regular...
Central and Peripheral Fatigue Evaluation during Physical Exercise in Athletic Horses by Means of Raman Spectroscopy.
Animals : an open access journal from MDPI    July 5, 2023   Volume 13, Issue 13 doi: 10.3390/ani13132201
Acri G, Testagrossa B, Piccione G, Arfuso F, Giudice E, Giannetto C.The evaluation of the performance levels in athletic horses is of major importance to prevent sports injuries. Raman spectroscopy is an innovative technique that allows for a rapid evaluation of biomolecules in biological fluids. It also permits qualitative and quantitative sample analyses, which lead to the simultaneous determination of the components of the examined biological fluids. On the basis of this, the Raman spectroscopy technique was applied on serum samples collected from five Italian Saddle horses subjected to a standardized obstacle course preceded by a warm-up to evaluate the ap...
Screening and confirmation of recombinant human follistatin in equine plasma for doping control purposes.
Drug testing and analysis    July 4, 2023   doi: 10.1002/dta.3540
Wong KS, Cheung HW, Choi YC, To NS, Wan TSM, Ho ENM.Recombinant human follistatin (rhFST) is a potential performance-enhancing agent owing to its stimulating effect on muscle growth. Administration of rhFST to athletes is prohibited in human sports by the World Anti-Doping Agency (WADA) and in horseracing according to Article 6 of the International Agreement on Breeding, Racing and Wagering published by the International Federation of Horseracing Authorities (IFHA). For effective control of the potential misuse of rhFST in flat racing, methods for screening and confirmatory analysis are required. This paper describes the development and validat...
Sex Hormone-Binding Globulin (SHBG) Maintains Proper Equine Adipose-Derived Stromal Cells (ASCs)’ Metabolic Functions and Negatively Regulates their Basal Adipogenic Potential.
Stem cell reviews and reports    July 4, 2023   Volume 19, Issue 7 2251-2273 doi: 10.1007/s12015-023-10580-8
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...
Travelling through the Natural Hierarchies of Type I Collagen with X-rays: From Tendons of Cattle, Horses, Sheep and Pigs.
Materials (Basel, Switzerland)    June 30, 2023   Volume 16, Issue 13 doi: 10.3390/ma16134753
Terzi A, Gallo N, Sibillano T, Altamura D, Masi A, Lassandro R, Sannino A, Salvatore L, Bunk O, Giannini C, De Caro L.Type I collagen physiological scaffold for tissue regeneration is considered one of the widely used biomaterials for tissue engineering and medical applications. It is hierarchically organized: five laterally staggered molecules are packed within fibrils, arranged into fascicles and bundles. The structural organization is correlated to the direction and intensity of the forces which can be loaded onto the tissue. For a tissue-specific regeneration, the required macro- and microstructure of a suitable biomaterial has been largely investigated. Conversely, the function of multiscale structural i...
Evaluation of the effects of medium-term (57-day) omeprazole administration and of omeprazole discontinuation on serum gastrin and serum chromogranin A concentrations in the horse.
Journal of veterinary internal medicine    June 30, 2023   Volume 37, Issue 4 1537-1543 doi: 10.1111/jvim.16795
Clark B, Steel C, Vokes J, Shan JR, Gedye K, Lovett A, Sykes BW.Rebound gastric hyperacidity (RGH) secondary to hypergastrinemia has been suggested to contribute to the rapid recurrence of equine squamous gastric disease (ESGD) in horses after discontinuation of omeprazole. Objective: To evaluate changes in serum gastrin and chromogranin A (CgA) concentrations in response to medium-term (57-day) omeprazole treatment and after omeprazole discontinuation. Methods: Fourteen mature Thoroughbred racehorses in simulated race training. Methods: Horses received 2.28 g of oral omeprazole PO q24h for 57 days within a 61-day period, excluding a withholding period...
Applicability of 2,4-dinitrophenylhydrazine (DNPH) method of protein oxidative damage measurement in the seminal plasma of canine ( Canis lupus familiaris) and stallion ( Equus caballus).
Polish journal of veterinary sciences    June 30, 2023   Volume 26, Issue 2 177-184 doi: 10.24425/pjvs.2023.145020
Mogielnicka-Brzozowska M, Woźniak MJ, Cichowska AW, Fraser L, Kraziński B, Strzezek R, Zielińska D.Seminal plasma (SP) proteins are responsible for sperm functional quality. Developing a reliable method to determine the degree of oxidative damage of these proteins is important for establishing semen fertilizing ability. The main aim of the study was to verify the applicability of protein carbonyl derivatives measurement in the SP of canine and stallion, using a method with 2,4-dinitrophenylhydrazine (DNPH). The research material consisted of ejaculates obtained from eight English Springer Spaniels, and from seven half-blood stallions during the breeding and non-breeding season. The content ...
Composition, architecture and biomechanical properties of articular cartilage in differently loaded areas of the equine stifle.
Equine veterinary journal    June 27, 2023   doi: 10.1111/evj.13960
Fugazzola M, Nissinen MT, Jäntti J, Tuppurainen J, Plomp S, Te Moller N, Mäkelä JTA, van Weeren R.Strategies for articular cartilage repair need to take into account topographical differences in tissue composition and architecture to achieve durable functional outcome. These have not yet been investigated in the equine stifle. Objective: To analyse the biochemical composition and architecture of three differently loaded areas of the equine stifle. We hypothesise that site differences correlate with the biomechanical characteristics of the cartilage. Methods: Ex vivo study. Methods: Thirty osteochondral plugs per location were harvested from the lateral trochlear ridge (LTR), the distal int...
High-throughput untargeted screening of biotherapeutic macromolecules in equine plasma by UHPLC-HRMS/MS: Application to monoclonal antibodies and Fc-fusion proteins for doping control.
Drug testing and analysis    June 20, 2023   doi: 10.1002/dta.3525
Pinetre J, Delcourt V, Becher F, Garcia P, Barnabé A, Loup B, Popot MA, Fenaille F, Bailly-Chouriberry L.Many innovative biotherapeutics have been marketed in the last decade. Monoclonal antibodies (mAbs) and Fc-fusion proteins (Fc-proteins) have been developed for the treatment of diverse diseases (cancer, autoimmune diseases, and inflammatory disorders) and now represent an important part of targeted therapies. However, the ready availability of such biomolecules, sometimes characterized by their anabolic, anti-inflammatory, or erythropoiesis-stimulating properties, raises concerns about their potential misuse as performance enhancers for human and animal athletes. In equine doping control labo...
Clinical effects of a combination of phenylbutazone and omeprazole on chronic lameness in Mongolian horses.
Equine veterinary journal    June 19, 2023   Volume 56, Issue 3 562-572 doi: 10.1111/evj.13962
Li Z, Du S, Wang X, Zhang L, Liu X, Fan Q, Yang H, Gao R.Phenylbutazone (PBZ) is the most commonly used drug to treat symptoms of lameness in horses; however, it is associated with adverse effects such as gastric ulcer syndrome (EGUS). Interestingly, many practitioners prescribe omeprazole (OME) concurrently with PBZ to prevent the development of EGUS. However, the efficacy and safety of this practice in Mongolian horses with chronic lameness remain unknown. Objective: To evaluate the clinical effects of a combination of PBZ and OME on chronic lameness in Mongolian horses. Methods: Randomised block experimental design. Methods: Eighteen Mongolian ho...
Lactate as the sole energy substrate induces spontaneous acrosome reaction in viable stallion spermatozoa.
Andrology    June 10, 2023   doi: 10.1111/andr.13479
Ramírez-Agámez L, Hernández-Avilés C, Ortíz I, Love CC, Varner DD, Hinrichs K.Equine spermatozoa appear to differ from spermatozoa of other species in using oxidative phosphorylation preferentially over glycolysis. However, there is little information regarding effects of different energy sources on measured parameters in equine spermatozoa. Objective: To determine the effect of three individual energy substrates, glucose, pyruvate, and lactate, on motion characteristics, membrane integrity, and acrosomal status of stallion spermatozoa. Methods: Freshly ejaculated stallion spermatozoa were incubated with combinations of glucose (5 mm), pyruvate (10 mm), and lactate (1...
Influence of Rho/ROCK inhibitor Y-27632 on proliferation of equine mesenchymal stromal cells.
Frontiers in veterinary science    June 6, 2023   Volume 10 1154987 doi: 10.3389/fvets.2023.1154987
Melzer M, Burk J, Guest DJ, Dudhia J.Mesenchymal stromal cells (MSC) isolated form bone marrow and adipose tissue are the most common cells used for cell therapy of orthopedic diseases. MSC derived from different tissues show differences in terms of their proliferation, differentiation potential and viability in prolonged cell culture. This suggests that there may be subtle differences in intracellular signaling pathways that modulate these cellular characteristics. The Rho/ROCK signaling pathway is essential for many cellular functions. Targeting of this pathway by the ROCK inhibitor Y-27632 has been shown to be beneficial for c...
Characterization of the Glycans of Equine κ-Casein.
Journal of agricultural and food chemistry    June 6, 2023   Volume 71, Issue 24 9460-9468 doi: 10.1021/acs.jafc.3c00452
Jaeser M, Wunderlich C, Henle T.To study the protein-bound glycans of equine κ-casein, equine sodium caseinate was first obtained from raw mare's milk by acid precipitation and then fractionated by cation-exchange chromatography. The oligosaccharides of the obtained equine κ-casein were analyzed by RP-HPLC-UV-HRMS after β-elimination with simultaneous derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). In addition to the acidic tetrasaccharide derivative Neu5Ac-Gal-[Neu5Ac]-GalNAc-2PMP known from bovine κ-casein, the acidic pentasaccharide derivative Neu5Ac-Gal-[Gal-GlcNAc]-GalNAc-2PMP was identified as the most ab...
Identification and kinetics of microsomal and recombinant equine liver cytochrome P450 enzymes responsible for in vitro metabolism of omeprazole.
Biochemical pharmacology    June 5, 2023   Volume 214 115635 doi: 10.1016/j.bcp.2023.115635
Ferlini Agne G, Somogyi AA, Sykes B, Knych H, Franklin S.In humans, omeprazole is metabolised by cytochrome P450 (CYP450) CYP2C19 and CYP3A4 with differences in CYP2C19 genotypes leading to variable response to therapy. Despite a wide use of omeprazole in horses with evidence of variable therapeutic efficiency, information regarding enzymatic metabolism is not currently available. This study aims to describe the in vitro kinetics of omeprazole metabolism and determine which enzyme(s) are responsible for omeprazole metabolism in horses. Omeprazole (0-800 uM) was incubated with liver microsomes and a panel of equine recombinant CYP450s (eq-rCYP). Meta...
Novel Expression of GLUT3, GLUT6 and GLUT10 in Equine Gluteal Muscle Following Glycogen-Depleting Exercise: Impact of Dietary Starch and Fat.
Metabolites    June 1, 2023   Volume 13, Issue 6 718 doi: 10.3390/metabo13060718
Valberg SJ, Velez-Irizarry D, Williams ZJ, Pagan JD, Mesquita V, Waldridge B, Maresca-Fichter H.Horses have a slow rate of muscle glycogen repletion relative to other species for unknown reasons. Our aim was to determine the expression of glucose transporters () and genes impacting GLUT4 expression and translocation in the gluteal muscle. Five fit Thoroughbred horses performed glycogen-depleting exercises on high-starch (HS, 2869 g starch/day) and low-starch, high-fat diets (LS-HF, 358 g starch/d) with gluteal muscle biopsies obtained before and after depletion and during repletion. Muscle glycogen declined by ≈30% on both diets with little increase during repletion on LS-HF. Transcrip...
A review of current chemistry, pharmacology, and regulation of endogenous anabolic steroids testosterone, boldenone, and nandrolone in horses.
Journal of veterinary pharmacology and therapeutics    June 1, 2023   Volume 46, Issue 4 201-217 doi: 10.1111/jvp.13397
Dirikolu L, Lehner AF.Anabolic androgenic steroids are synthetic substances related to the male sex hormones (androgens). These agents promote the growth of skeletal muscle (anabolic effects) and the development of male sexual characteristics (androgenic effects). Anabolic steroids have been illegally used for many years as performance-enhancing drugs in human, equine, and canine sports and as growth promoters in livestock reared to provide meat for human consumption. The analytical challenge to developing effective means of control within these fields has been exacerbated by the reported endogenous nature of some ...
Effect of diet composition on glandular gastric disease in horses.
Journal of veterinary internal medicine    June 1, 2023   Volume 37, Issue 4 1528-1536 doi: 10.1111/jvim.16747
Julliand S, Buttet M, Hermange T, Hillon P, Julliand V.Nutritional factors are suggested to influence the incidence and severity of glandular gastric disease (GGD) in horses. Objective: To retrospectively assess whether dietary fermentable carbohydrates increase the severity of GGD and to prospectively evaluate whether the partial substitution of concentrates by dehydrated alfalfa would decrease GGD severity scores. Methods: In total, 82 trotters from 4 training centers exercised ≥5 days/week. Methods: Multicenter retrospective observational study, and prospective 2-arm randomized trial. Glandular mucosae were observed by gastroscopy and score...
Production of Mare Chorionic Girdle Organoids That Secrete Equine Chorionic Gonadotropin.
International journal of molecular sciences    May 31, 2023   Volume 24, Issue 11 9538 doi: 10.3390/ijms24119538
Thompson RE, Meyers MA, Palmer J, Veeramachaneni DNR, Magee C, de Mestre AM, Antczak DF, Hollinshead FK.The equine chorionic girdle is comprised of specialized invasive trophoblast cells that begin formation approximately 25 days after ovulation (day 0) and invade the endometrium to become endometrial cups. These specialized trophoblast cells transition from uninucleate to differentiated binucleate trophoblast cells that secrete the glycoprotein hormone equine chorionic gonadotropin (eCG; formerly known as pregnant mare serum gonadotropin or PMSG). This eCG has LH-like activity in the horse but variable LH- and FSH-like activity in other species and has been utilized for these properties both in...
Multiple myeloma presenting as blepharitis in a horse.
Veterinary clinical pathology    May 29, 2023   Volume 52, Issue 3 514-520 doi: 10.1111/vcp.13227
Hayes AM, Kastl B, Perry E, Moore AR, Springer NL.Myeloma-related disorders, including multiple myeloma, extramedullary plasmacytoma, and solid osseous plasmacytoma, are rare in horses. Clinical complaints for myeloma-related disorders are nonspecific, and when present, M-protein location is more variable on protein electrophoresis in horses relative to dogs and cats. Here, we describe a case of a 15-year-old Thoroughbred mare who presented with recurrent blepharitis. Marked hyperglobulinemia was an incidental finding on routine hematologic and biochemical testing. Bone marrow aspiration consisted of >30% plasma cells, and serum protein el...
Horse serum or equine platelet lysate increases total vascular endothelial growth factor A concentrations and correlates with vascular growth in an equine facial arterial ring assay.
American journal of veterinary research    May 29, 2023   Volume 84, Issue 7 ajvr.23.02.0023 doi: 10.2460/ajvr.23.02.0023
Mora-Pereira M, Boone L, Naskou M, Wooldridge A.To evaluate ex vivo angiogenesis of equine arterial rings in response to various growth media. Methods: Facial arteries were dissected from 11 horses post-euthanasia. Equine platelet lysate (ePL) was harvested from 6 horses. Methods: Arteries were exposed to endothelial growth media (EGM) + horse serum (HS) for first sprout (FS), vascular regression (VR), and (basement membrane matrix [Matrigel]) lysis (ML) evaluation. Additional rings supplemented with (1) EGM, (2) EGM + EDTA, (3) endothelial basal media (EBM), (4) EBM + HS, or (5) EBM + human VEGF were compared for vascular network area (VNA...
Ingesta-associated choledocholithiasis in horses: 2 cases and literature review. Linn-Peirano SC, Hepworth-Warren K, Kinsella H, Diaz-Campos D, Brenseke BM, Cianciolo RE, Schroeder E, Schreeg ME.Equine ingesta-associated choledocholithiasis is a rare cause of morbidity and mortality. We describe here the clinical, gross, histologic, and microbiologic features of this condition in 2 horses and compare the features to 2 previous cases. Case 1 was a 4-y-old Thoroughbred mare with colic. Case 2 was an 18-y-old American Paint Horse mare with colic, chronic weight loss, and inappropriate mentation. Both had elevated biochemical markers of hepatocellular injury and cholestasis and were euthanized given a poor prognosis. Case 1 had a well-formed 5-cm choledocholith surrounding a piece of hay,...
Berbamine, a bioactive alkaloid, suppresses equine herpesvirus type 1 in vitro and in vivo.
Frontiers in veterinary science    May 25, 2023   Volume 10 1163780 doi: 10.3389/fvets.2023.1163780
Li Z, He Y, Ge L, Quan R, Chen J, Hu Y, Sa R, Liu J, Ran D, Fu Q, Shi H.Equine herpesvirus type 1 (EHV-1) poses a global threat to equines. The anticancer agent berbamine (BBM), a bioactive alkaloid, has been shown to inhibit viral infection. However, whether BBM can inhibit EHV-1 infection remains unclear. This study investigated the effect of BBM treatment on EHV-1 infection. Quantitative PCR (qPCR), immunoblotting, the Reed-Muench method, and pathological examination were employed to study the ability of BBM to inhibit EHV-1 infection, viral DNA replication, viral protein production, virion secretion, and cytopathogenesis in vitro and in vivo. The in vitro stud...
Osmolarity modulates the de-differentiation of horse articular chondrocytes during cell expansion in vitro: implications for tissue engineering in cartilage repair.
Veterinary research communications    May 19, 2023   doi: 10.1007/s11259-023-10140-y
De Angelis E, Barilli A, Saleri R, Rotoli BM, Ravanetti F, Ferrari F, Ferrari L, Martelli P, Dall'Asta V, Borghetti P.Due to the importance of joint disease and ostearthritis (OA) in equine athletes, new regenerative treatments to improve articular cartilage repair after damage are gaining relevance. Chondrocyte de-differentiation, an important pathogenetic mechanism in OA, is a limiting factor when differentiated articular chondrocytes are used for cell-based therapies. Current research focuses on the prevention of this de-differentiation and/or on the re-differentiation of chondrocytes by employing different strategies in vitro and in vivo. Articular chondrocytes normally live in a condition of higher osmol...
Circulating miR-146b and miR-27b are efficient biomarkers for early diagnosis of Equidae osteoarthritis.
Scientific reports    May 17, 2023   Volume 13, Issue 1 7966 doi: 10.1038/s41598-023-35207-3
Yassin AM, AbuBakr HO, Abdelgalil AI, Farid OA, El-Behairy AM, Gouda EM.One of the most orthopedic problems seen in the equine is osteoarthritis (OA). The present study tracks some biochemical, epigenetic, and transcriptomic factors along different stages of monoiodoacetate (MIA) induced OA in donkeys in serum and synovial fluid. The aim of the study was the detection of sensitive noninvasive early biomarkers. OA was induced by a single intra-articular injection of 25 mg of MIA into the left radiocarpal joint of nine donkeys. Serum and synovial samples were taken at zero-day and different intervals for assessment of total GAGs and CS levels as well as miR-146b, m...
Comparison of muscle metabolomics between two Chinese horse breeds.
Frontiers in veterinary science    May 5, 2023   Volume 10 1162953 doi: 10.3389/fvets.2023.1162953
Meng S, Zhang Y, Lv S, Zhang Z, Liu X, Jiang L.With their enormous muscle mass and athletic ability, horses are well-positioned as model organisms for understanding muscle metabolism. There are two different types of horse breeds-Guanzhong (GZ) horses, an athletic breed with a larger body height (~148.7 cm), and the Ningqiang pony (NQ) horses, a lower height breed generally used for ornamental purposes-both inhabited in the same region of China with obvious differences in muscle content. The main objective of this study was to evaluate the breed-specific mechanisms controlling muscle metabolism. In this study, we observed muscle glycogen, ...
The use of shotgun label-free quantitative proteomic mass spectrometry to evaluate the inflammatory response in aqueous humor from horses with uveitis compared to ophthalmologically healthy horses.
Veterinary ophthalmology    May 5, 2023   doi: 10.1111/vop.13107
Terhaar HM, Henriksen ML, Mehaffy C, Hess A, McMullen RJ.The objective of this study was to use shotgun label-free tandem mass spectrometry (LF-MS/MS) to evaluate aqueous humor (AH) from horses with uveitis (UH) compared to ophthalmologically healthy horses (HH). Methods: Twelve horses diagnosed with uveitis based on ophthalmic examination and six ophthalmologically healthy horses (postmortem) purchased for teaching purposes. Methods: All horses received a complete ophthalmic examination and physical exam. Aqueous paracentesis was performed on all horses and AH total protein concentrations were measured with nanodrop (TPn) and refractometry (TPr). A...
Effect of dietary krill oil supplementation on horse red blood cell membrane fatty acid composition and blood parameters.
Journal of animal physiology and animal nutrition    May 5, 2023   Volume 107, Issue 5 1251-1261 doi: 10.1111/jpn.13828
Nyquist NF, Burri L, Jensen RB.Supplementation with marine-derived n-3 long-chain polyunsaturated fatty acids (LC PUFAs), eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) is linked to beneficial health effects in both humans and horses. Krill oil (KO), which is extracted from the Antarctic krill (Euphausia superba), is well documented as a safe and biologically available dietary supplement in humans and several animal species, but there is a lack of documentation regarding its effect as a dietary ingredient for horses. The objective of this study was to test whether KO as a dietary supplement h...
Collaborative study for the calibration of a replacement International Standard for Diphtheria Antitoxin Equine.
Biologicals : journal of the International Association of Biological Standardization    May 5, 2023   Volume 82 101682 doi: 10.1016/j.biologicals.2023.101682
Hassall L, Rigsby P, Stickings P.The International Standard for Diphtheria Antitoxin Equine is essential for the standardisation of assays used to determine the potency of therapeutic diphtheria antitoxin products produced from equine serum. This paper describes the production and characterization of the 2nd International Standard for Diphtheria Antitoxin Equine and its calibration in International Units. Calibration was performed by toxin neutralization test in vivo and in vitro (Vero cell assay), and potency was expressed relative to the 1st International Standard to ensure continuity of the International Unit. The candidat...
Detection of gonadotropin-releasing hormone and its analogues in equine and canine urine by high-resolution data-independent acquisition.
Drug testing and analysis    May 3, 2023   Volume 15, Issue 8 896-908 doi: 10.1002/dta.3486
Timms M, Botteon A, Manos C, Griffin J, Levina V, Steel R.Gonadotropin-releasing hormone (GnRH) and its synthetic analogues are considered banned substances by the racing industry. GnRH is used as a pharmaceutical to regulate the female oestrous cycle, but the hormone is also thought to increase the production of testosterone in male animals. Using liquid chromatography in conjunction with high-resolution mass spectrometry (LC-HRMS) and data-independent acquisition (DIA), a method is presented for the detection of intact and truncated peptides of GnRH and its analogues down to the low picogram level in equine urine. The study of the catabolism of GnR...
Electrospray ionization mass spectrometry adduct formation by mobile phase additives: A case study using nitrile functional groups containing selective androgen receptor modulators.
Rapid communications in mass spectrometry : RCM    May 1, 2023   Volume 37, Issue 14 e9530 doi: 10.1002/rcm.9530
Karatt TK, Muhammed Ajeebsanu M, Karakka Kal AK, Subhahar MB, Sathiq MA, Laya S.The formation of mass adducts is common during electrospray ionization mass spectrometry (ESI-MS). However, the mechanism that leads to adduct formation is poorly understood and difficult to control. Multiplication of mass adducts at once will adversely impact the sensitivity of mass analysis and cause misinterpretation of the level of detection. Prior studies on selective androgen receptor modulators (SARMs) revealed an immense mass adduct formation in both positive and negative ESI modes. Methods: In this study, additives in the mobile phases are investigated as a potential means of controll...