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Background: The Central American bushmaster (Lachesis stenophrys) is one of the largest pitvipers in the Americas, with relatively low abundance, suspected population declines, and continuing loss, fragmentation, and habitat degradation. Aim: Conservation actions, both in the wild and in captivity, bear the need for health parameters that allow managers and veterinarians to have a better understanding of health, especially when there are relatively few individuals in captivity to obtain robust information since there is no published information on the genus. To have hematological and biochemical reference ranges on the genus Lachesis. Methods: Blood samples were collected from 32 individuals (18 females and 14 males) under human care from 7 zoological institutions from August 2022 to January 2023 and performed hematological and biochemical analyses. Results: Reference intervals of hematological analytes included packed cell volume (17.51%-37.27%), total red blood cell count (0.36-0.92 × 1012/l), hemoglobin (61.73-145.23 g/l), white blood cell count (3.18-13.79 × 109/l), lymphocytes (2.16%-11.23%), azurophils (0.50%-4.20%), monocytes (0.00%-0.21%), heterophils (0.05%-1.12%), eosinophils (0.00%-0.19%), basophils (0.00%-2.00%), and total thrombocyte count (0.68-6.68 × 109/l), and biochemistry reference intervals included total protein (41.76-111.31 g/l), albumin (11.46-28.69 g/l), globulins (29.25-85.14 g/l), aspartate aminotransferase (1.44-68.75 U/l), creatinine kinase (52.72-625.00 U/l), uric acid (20.02-438.53 µmol/l), glucose (0.68-3.29 mml/l), cholesterol (41.74-13.25 mmol/l), calcium (1.78-6.06 mmol/l), and phosphorus (0.72-2.26 mmol/l). Conclusion: This is the first report on the genus Lachesis reporting hematological and biochemical reference ranges.

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Acute myocardial infarction is one of the leading causes of death worldwide and thus, an extensively studied disease. Nonetheless, the effects of ischemia/reperfusion injury elicited by oxidative stress on cardiac fibroblast function associated with tissue repair are not completely understood. Ascorbic acid, deferoxamine, and N-acetylcysteine (A/D/N) are antioxidants with known cardioprotective effects, but the potential beneficial effects of combining these antioxidants in the tissue repair properties of cardiac fibroblasts remain unknown. Thus, the aim of this study was to evaluate whether the pharmacological association of these antioxidants, at low concentrations, could confer protection to cardiac fibroblasts against simulated ischemia/reperfusion injury. To test this, neonatal rat cardiac fibroblasts were subjected to simulated ischemia/reperfusion in the presence or absence of A/D/N treatment added at the beginning of simulated reperfusion. Cell viability was assessed using trypan blue staining, and intracellular reactive oxygen species (ROS) production was assessed using a 2',7'-dichlorofluorescin diacetate probe. Cell death was measured by flow cytometry using propidium iodide. Cell signaling mechanisms, differentiation into myofibroblasts and pro-collagen I production were determined by Western blot, whereas migration was evaluated using the wound healing assay. Our results show that A/D/N association using a low concentration of each antioxidant increased cardiac fibroblast viability, but that their separate administration did not provide protection. In addition, A/D/N association attenuated oxidative stress triggered by simulated ischemia/reperfusion, induced phosphorylation of pro-survival extracellular-signal-regulated kinases 1/2 (ERK1/2) and PKB (protein kinase B)/Akt, and decreased phosphorylation of the pro-apoptotic proteins p38- mitogen-activated protein kinase (p38-MAPK) and c-Jun-N-terminal kinase (JNK). Moreover, treatment with A/D/N also reduced reperfusion-induced apoptosis, evidenced by a decrease in the sub-G1 population, lower fragmentation of pro-caspases 9 and 3, as well as increased B-cell lymphomaextra large protein (Bcl-xL)/Bcl-2-associated X protein (Bax) ratio. Furthermore, simulated ischemia/reperfusion abolished serum-induced migration, TGF-ß1 (transforming growth factor beta 1)-mediated cardiac fibroblast-to-cardiac myofibroblast differentiation, and angiotensin II-induced pro-collagen I synthesis, but these effects were prevented by treatment with A/D/N. In conclusion, this is the first study where a pharmacological combination of A/D/N, at low concentrations, protected cardiac fibroblast viability and function after simulated ischemia/reperfusion, and thereby represents a novel therapeutic approach for cardioprotection.