Inhibition of the Low Molecular Weight Protein Tyrosine Phosphatase (LMPTP) as a Potential Therapeutic Strategy for Hepatic Progenitor Cells Lipotoxicity-Short Communication.

Equine metabolic syndrome (EMS) is a cluster of metabolic disorders, such as obesity, hyperinsulinemia, and hyperleptinemia, as well as insulin resistance (IR). In accordance with the theory linking obesity and IR, excessive accumulation of lipids in insulin-sensitive tissues (lipotoxicity), like liver, alters several cellular functions, including insulin signaling. Therefore, the purpose of the study was to isolate equine hepatic progenitor-like cells (HPCs) and assess whether inhibition of low molecular weight protein tyrosine phosphatase (LMPTP) affects the expression of genes involved in macroautophagy, chaperone-mediated autophagy (CMA), endoplasmic reticulum stress, and mitochondrial dynamics in a palmitate-induced IR model. We demonstrated that LMPTP inhibition significantly enhanced expression of heat shock cognate 70 kDa protein (HSC70), lysosome-associated membrane protein 2 (LAMP2), and parkin (PRKN), all master regulators of selective autophagy. We also observed downregulation of C/EBP homologous protein (CHOP), activating transcription factor 6 (ATF6) and binding immunoglobulin protein encoded by the HSPA gene. Moreover, LMPTP inhibition increased alternative splicing of X-box binding protein 1 (XBP1), suggesting high endonuclease activity of inositol-requiring enzyme 1 alpha (IRE1α). Taken together, our data provide convincing evidence that LMPTP inhibition reverses palmitate-induced insulin resistance and lipotoxicity. In conclusion, this study highlights the role of LMPTP in the regulation of CMA, mitophagy, and ER stress, and provides a new in vitro model for studying HPC lipotoxicity in pre-clinical research.

Characterization of Apoptosis, Autophagy and Oxidative Stress in Pancreatic Islets Cells and Intestinal Epithelial Cells Isolated from Equine Metabolic Syndrome (EMS) Horses.

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 intestinal epithelial stem cells (IECs) and pancreatic islets (PIs) isolated post mortem form healthy and EMS diagnosed horses. Our group was the first to describe how EMS affects IEC and PI aging and senescence. First, we evaluated isolation and culture protocol for these cells and subsequently established their metabolic status in vitro. Both IECs and PIs isolated from EMS horses were characterized by increased apoptosis and senescence. Moreover, they accumulated elevated levels of reactive oxygen species (ROS). Here we have observed that autophagy/mitophagy may be a protective mechanism which allows those cells to maintain their physiological function, clear protein aggregates and remove damaged organelles. Furthermore, it may play a crucial role in reducing endoplasmic reticulum (ER) stress. This protective mechanism may help to overcome the harmful effects of ROS and provide building blocks for protein and ATP synthesis.

Two-step surgery combining standing laparoscopy with recumbent ventral median celiotomy for removal of enlarged pathologic ovaries in 20 mares.

OBJECTIVES: To report a combination of standing laparoscopic technique for intra-abdominal dissection of the mesovarial pedicle followed by a limited ventral median celiotomy under general anesthesia for removal of enlarged ovaries in mares. STUDY DESIGN: Case series. ANIMALS: Mares (n = 20) aged 3-22 years with unilateral enlarged ovaries. METHODS: Enlarged ovaries were confirmed by transrectal palpation and ultrasonography. After sedation, 3 laparoscopic portals were made in the paralumbar fossa. The mesovarium was desensitized and dissected using a vessel sealing device, and the ovary was left free in the abdomen. Then under general anesthesia, the mare was positioned in dorsal recumbency and an 8 cm ventral median celiotomy made for ovary retrieval in a specimen bag. RESULTS: This 2-step procedure was successfully used for removal enlarged ovaries (12-50 cm) in 17 mares and for management of behavioral problems in 3 mares. No operative or postoperative complications occurred. Owner satisfaction and cosmesis were considered excellent. CONCLUSIONS: Standing laparoscopy combined with a limited median celiotomy is a safe technique for ovariectomy in mares. This technique mitigates most of the disadvantages of standing flank ovariectomy and a conventional open ventral median approach.

Comparison of a point-of-care serum amyloid A analyzer frequently used in equine practice with 2 turbidimetric immunoassays used in human and veterinary medicine.

Rapid, accurate detection of serum amyloid A (SAA) is needed in equine practice. We validated a patient-side point-of-care (POC) assay (Stablelab; Zoetis) compared to the turbidimetric immunoassays LZ-SAA (TIA-Hum) and VET-SAA (TIA-Vet; both Eiken Chemical). Analytical performance was assessed at 3 different concentration ranges and with interferences. Inter-method comparison using 49 equine serum samples revealed a significant difference between median SAA results (p < 0.0001), with the strongest bias between the POC and TIA-Vet (median 1,093 vs. 578 mg/L). The median SAA value obtained with the TIA-Hum method was 752 mg/L. Correlation between POC/TIA-Hum and between POC/TIA-Vet was fair (rs = 0.77 and 0.69) and excellent between both TIAs (rs = 0.93). Bias between POC/TIA-Hum, POC/TIA-Vet, and TIA-Hum/TIA-Vet was -56.7%, -80.9%, and -28.2%, respectively. POC intra- and inter-assay CVs (16.1-30% and 19.8-35.5%) were higher than TIA CVs (generally <12%). Bilirubin and hemoglobin had a negative bias on POC and TIA-Vet results (-16.6 to -45.6%); addition of intralipid yielded a positive bias (35.9-77.4%). The POC had good linearity of SAA concentrations up to 10,312 mg/L (R2 = 0.92). A hook effect was present at SAA >3,000 mg/L for the POC assay. Equine serum SAA was stable over a median period of 2.5 y when stored at -80°C. Overall, there was excellent-to-moderate correlation between tests, but imprecision and hook effect of the POC, as well as bias between the methods, must be considered.

Effect of Perineural Anesthesia on the Centre of Pressure (COP) Path During Stance Phase at Trot in Sound Horses.

This study aimed to examine how short-term loss of proprioception in the equine foot influences the individual COP path during the stance phase of the trot in sound horses. Ten horses were evaluated to be objectively non-lame using the 'Equinosis Q System and subsequently examined using a portable pressure measuring system with pressure foils fixed directly underneath both front hooves prior to and after perineural anesthesia of the palmar digital nerves. The individual COP paths of both forelimbs was assessed prior to and after unilateral and bilateral abaxial sesamoid nerve blocks. COP from initial contact to mid stance and breakover as well as the inter-stride variability were descriptively evaluated for each horse and limb. The individual COP path for each horse and limb during stance was shown to be highly repeatable without significant inter-stride variability. Location of initial contact, COP during midstance and breakover are not affected by unilateral or bilateral short-term loss of sensory feedback from the foot after perineural anesthesia. Anesthesia of the foot with an abaxial sesamoid nerve block does not affect the foot's COP during stance at a trot, therefore, sudden changes in gait pattern after perineural anesthesia should be interpreted with caution and warrant further clinical investigation.

Promotion through external magnetic field of osteogenic differentiation potential in adipose-derived mesenchymal stem cells: Design of polyurethane/poly(lactic) acid sponges doped with iron oxide nanoparticles.

Recently, iron oxide nanoparticles (IONPs) have gathered special attention in regenerative medicine. Owing to their magnetic and bioactive properties, IONPs are utilized in the fabrication of novel biomaterials. Yet, there was no report regarding thermoplastic polyurethane (TPU) and poly(lactic acid) (PLA) polymer doped with IONPs on osteogenic differentiation of mesenchymal stem cells. Thus the objectives of presented study was to: (a) fabricate magnetic TPU + PLA sponges doped with iron (III) oxide Fe2 O3 nanoparticles; (b) investigate the effects of biomaterial and its exposition to static magnetic field (MF) on osteogenic differentiation, proliferation, and apoptosis in adipose-derived mesenchymal stem cells (ASCs). TPU + PLA sponges were prepared using solvent casting technique while incorporation of the Fe2 O3 nanoparticles was performed with solution cast method. RT-PCR was applied to evaluate expression of osteogenic-related genes and integrin's in cells cultured on fabricated materials with or without the stimulation of static MF. MF stimulation enhanced the expression of osteopontin and collagen type I while decreased expression of bone morphogenetic protein 2 in tested magnetic materials-TPU + PLA/1% Fe2 O3 and TPU + PLA/5% Fe2 O3 . Therefore, TPU + PLA sponges doped with IONPs and exposure to MF resulted in improved osteogenic differentiation of ASC.

Investigation of Pyrophosphates KYP2O7Co-Doped with Lanthanide Ions Useful for Theranostics.

Diphosphate compounds (KYP2O7) co-doped with Yb3+ and Er3+ ions were obtained by one step urea assisted combustion synthesis. The experimental parameters of synthesis were optimized using an experimental design approach related to co-dopants concentration and heattreatment as well as annealing time. The obtained materials were studied with theinitial requirements showing appropriate morphological (X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM)) and spectroscopic properties (emission, luminescence kinetics). Moreover, the effect of Er3+ and Yb3+ ions doped KYP2O7 on morphology, proliferative and metabolic activity and apoptosis in MC3T3-E1 osteoblast cell line and 4B12osteoclasts cell line was investigated. Furthermore, the expression of the common pro-osteogenic markers in MC3T3-E1 osteoblast as well as osteoclastogenesis related markers in 4B12 osteoclasts was evaluated. The extensive in vitro studies showed that KYP2O7 doped with 1 mol% Er3+ and 20 mol% Yb3+ ions positively affected the MC3T3-E1 and 4B12 cells activity without triggering their apoptosis. Moreover, it was shown that an activation of mTOR and Pi3k signaling pathways with 1 mol% Er3+, 20 mol% Yb3+: KYP2O7 can promote the MC3T3-E1 cells expression of late osteogenic markers including RUNX and BMP-2. The obtained data shed a promising light for KYP2O7 doped with Er3+ and Yb3+ ions as a potential factors improving bone fracture healing as well as in bioimaging (so-called in theranostics).