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Petro JL, Milán AF, Arenas E, Valle L, Hernández V, Calderón JC. Intact Short, Intermediate, and Long Skeletal Muscle Fibers Obtained by Enzymatic Dissociation of Six Hindlimb Muscles of Mice: Beyond Flexor Digitorum Brevis. J Vis Exp 2023. [PMID: 38108405 DOI: 10.3791/65851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023] Open
Abstract
Skeletal muscle fibers obtained by enzymatic dissociation of mouse muscles are a useful model for physiological experiments. However, most papers deal with the short fibers of the flexor digitorum brevis (FDB), which restrains the scope of results dealing with fiber types, limits the amount of biological material available, and impedes a clear connection between cellular physiological phenomena and previous biochemical and dynamical knowledge obtained in other muscles. This paper describes how to obtain intact fibers from six muscles with different fiber type profiles and lengths. Using C57BL/6 adult mice, we show the muscle dissection and fiber isolation protocol and demonstrate the suitability of the fibers for Ca2+ transient studies and their morphometric characterization. The fiber type composition of the muscles is also presented. When dissociated, all muscles rendered intact, living fibers that contract briskly for more than 24 h. FDB gave short (<1 mm), peroneus digiti quarti (PDQA) and peroneus longus (PL) gave intermediate (1-3 mm), while extensor digitorum longus (EDL), extensor hallucis longus (EHL), and soleus muscles released long (3-6 mm) fibers. When recorded with the fast dye Mag-Fluo-4, Ca2+ transients of PDQA, PL, and EHL fibers showed the fast, narrow kinetics reminiscent of the morphology type II (MT-II), known to correspond to type IIX and IIB fibers. This is consistent with the fact that these muscles have over 90% of type II fibers compared with FDB (~80%) and soleus (~65%). Moving beyond FDB, we demonstrate for the first time the dissociation of several muscles, which render fibers spanning a range of lengths between 1 and 6 mm. These fibers are viable and give fast Ca2+ transients, indicating that the MT-II can be generalized to IIX and IIB fast fibers, regardless of their muscle source. These results increase the availability of models for mature skeletal muscle studies.
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Affiliation(s)
- Jorge L Petro
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia
| | - Andrés F Milán
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia
| | - Erika Arenas
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia
| | - Laura Valle
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia
| | - Valeria Hernández
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia
| | - Juan C Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia;
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Petro JL, Fragozo-Ramos MC, Milán AF, Aristizabal JC, Gallo-Villegas JA, Calderón JC. Serum Levels of Myonectin Are Lower in Adults with Metabolic Syndrome and Are Negatively Correlated with Android Fat Mass. Int J Mol Sci 2023; 24:ijms24086874. [PMID: 37108038 PMCID: PMC10138930 DOI: 10.3390/ijms24086874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 02/21/2023] [Accepted: 02/24/2023] [Indexed: 04/29/2023] Open
Abstract
Myonectin has shown beneficial effects on lipid regulation in murine models; therefore, it may have implications in the pathophysiology of metabolic syndrome (MS). We evaluated the relationship between serum myonectin and serum lipids, global and regional fat mass, intramuscular lipid content, and insulin resistance (IR) in adults with metabolic risk factors. This was a cross-sectional study in sedentary adults who were diagnosed with MS or without MS (NMS). Serum myonectin was quantified by enzyme-linked immunosorbent assay, lipid profile by conventional techniques, and free fatty acids (FFA) by gas chromatography. Body composition was assessed by dual-energy X-ray absorptiometry and intramuscular lipid content through proton nuclear magnetic resonance spectroscopy in the right vastus lateralis muscle. IR was estimated with the homeostatic model assessment (HOMA-IR). The MS (n = 61) and NMS (n = 29) groups were comparable in age (median (interquartile range): 51.0 (46.0-56.0) vs. 53.0 (45.5-57.5) years, p > 0.05) and sex (70.5% men vs. 72.4% women). MS subjects had lower serum levels of myonectin than NMS subjects (1.08 (0.87-1.35) vs. 1.09 (0.93-4.05) ng·mL-1, p < 0.05). Multiple linear regression models adjusted for age, sex, fat mass index and lean mass index showed that serum myonectin was negatively correlated with the android/gynoid fat mass ratio (R2 = 0.48, p < 0.01), but not with the lipid profile, FFA, intramuscular lipid content or HOMA-IR. In conclusion, serum myonectin is lower in subjects with MS. Myonectin negatively correlates with a component relevant to the pathophysiology of MS, such as the android/gynoid fat mass ratio, but not with other components such as FFA, intramuscular fat or IR.
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Affiliation(s)
- Jorge L Petro
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
- Research Group in Physical Activity, Sports and Health Sciences-GICAFS, Universidad de Córdoba, Montería 230002, Colombia
| | - María Carolina Fragozo-Ramos
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
| | - Andrés F Milán
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
| | - Juan C Aristizabal
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
| | - Jaime A Gallo-Villegas
- Sports Medicine Postgraduate Program, and GRINMADE Research Group, SICOR Center, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
| | - Juan C Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia
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Rincón OA, Milán AF, Calderón JC, Giraldo MA. Comprehensive Simulation of Ca 2+ Transients in the Continuum of Mouse Skeletal Muscle Fiber Types. Int J Mol Sci 2021; 22:12378. [PMID: 34830262 PMCID: PMC8624975 DOI: 10.3390/ijms222212378] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/01/2021] [Accepted: 10/12/2021] [Indexed: 01/19/2023] Open
Abstract
Mag-Fluo-4 has revealed differences in the kinetics of the Ca2+ transients of mammalian fiber types (I, IIA, IIX, and IIB). We simulated the changes in [Ca2+] through the sarcomere of these four fiber types, considering classical (troponin -Tn-, parvalbumin -Pv-, adenosine triphosphate -ATP-, sarcoplasmic reticulum Ca2+ pump -SERCA-, and dye) and new (mitochondria -MITO-, Na+/Ca2+ exchanger -NCX-, and store-operated calcium entry -SOCE-) Ca2+ binding sites, during single and tetanic stimulation. We found that during a single twitch, the sarcoplasmic peak [Ca2+] for fibers type IIB and IIX was around 16 µM, and for fibers type I and IIA reached 10-13 µM. The release rate in fibers type I, IIA, IIX, and IIB was 64.8, 153.6, 238.8, and 244.5 µM ms-1, respectively. Both the pattern of change and the peak concentrations of the Ca2+-bound species in the sarcoplasm (Tn, PV, ATP, and dye), the sarcolemma (NCX, SOCE), and the SR (SERCA) showed the order IIB ≥ IIX > IIA > I. The capacity of the NCX was 2.5, 1.3, 0.9, and 0.8% of the capacity of SERCA, for fibers type I, IIA, IIX, and IIB, respectively. MITO peak [Ca2+] ranged from 0.93 to 0.23 µM, in fibers type I and IIB, respectively, while intermediate values were obtained in fibers IIA and IIX. The latter numbers doubled during tetanic stimulation. In conclusion, we presented a comprehensive mathematical model of the excitation-contraction coupling that integrated most classical and novel Ca2+ handling mechanisms, overcoming the limitations of the fast- vs. slow-fibers dichotomy and the use of slow dyes.
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Affiliation(s)
- Oscar A. Rincón
- Biophysics Group, Institute of Physics, University of Antioquia, Medellín 050010, Colombia;
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia; (A.F.M.); (J.C.C.)
| | - Andrés F. Milán
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia; (A.F.M.); (J.C.C.)
| | - Juan C. Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín 050010, Colombia; (A.F.M.); (J.C.C.)
| | - Marco A. Giraldo
- Biophysics Group, Institute of Physics, University of Antioquia, Medellín 050010, Colombia;
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Sánchez YL, Yepes-Calderón M, Valbuena L, Milán AF, Trillos-Almanza MC, Granados S, Peña M, Estrada-Castrillón M, Aristizábal JC, Narvez-Sanchez R, Gallo-Villegas J, Calderón JC. Musclin Is Related to Insulin Resistance and Body Composition, but Not to Body Mass Index or Cardiorespiratory Capacity in Adults. Endocrinol Metab (Seoul) 2021; 36:1055-1068. [PMID: 34674511 PMCID: PMC8566119 DOI: 10.3803/enm.2021.1104] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/24/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND We studied whether musclin function in humans is related to glycemic control, body composition, and cardiorespiratory capacity. METHODS A cross-sectional study was performed in sedentary adults with or without metabolic syndrome (MS). Serum musclin was measured by enzyme-linked immunosorbent assay. Insulin resistance (IR) was evaluated by the homeostatic model assessment (HOMA-IR). Body composition was determined by dual-energy X-ray absorptiometry and muscle composition by measuring carnosine in the thigh, a surrogate of fiber types, through proton magnetic resonance spectroscopy. Cardiorespiratory capacity was assessed through direct ergospirometry. RESULTS The control (n=29) and MS (n=61) groups were comparable in age (51.5±6.5 years old vs. 50.7±6.1 years old), sex (72.4% vs. 70.5% women), total lean mass (58.5%±7.4% vs. 57.3%±6.8%), and peak oxygen consumption (VO2peak) (31.0±5.8 mL O2./kg.min vs. 29.2±6.3 mL O2/kg.min). Individuals with MS had higher body mass index (BMI) (30.6±4.0 kg/m2 vs. 27.4± 3.6 kg/m2), HOMA-IR (3.5 [95% confidence interval, CI, 2.9 to 4.6] vs. 1.7 [95% CI, 1.1 to 2.0]), and musclin (206.7 pg/mL [95% CI, 122.7 to 387.8] vs. 111.1 pg/mL [95% CI, 63.2 to 218.5]) values than controls (P˂0.05). Musclin showed a significant relationship with HOMA-IR (β=0.23; 95% CI, 0.12 to 0.33; P˂0.01), but not with VO2peak, in multiple linear regression models adjusted for age, sex, fat mass, lean mass, and physical activity. Musclin was significantly associated with insulin, glycemia, visceral fat, and regional muscle mass, but not with BMI, VCO2peak, maximum heart rate, maximum time of work, or carnosine. CONCLUSION In humans, musclin positively correlates with insulinemia, IR, and a body composition profile with high visceral adiposity and lean mass, but low body fat percentage. Musclin is not related to BMI or cardiorespiratory capacity.
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Affiliation(s)
- Yeliana L. Sánchez
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Manuela Yepes-Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Luis Valbuena
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
- Indeportes Antioquia, Medellin,
Colombia
| | - Andrés F. Milán
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - María C. Trillos-Almanza
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Sergio Granados
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Miguel Peña
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | | | - Juan C. Aristizábal
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Raúl Narvez-Sanchez
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Jaime Gallo-Villegas
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
- Sports Medicine Postgraduate Program, and GRINMADE Research Group, SICOR Center, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
| | - Juan C. Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin,
Colombia
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Milán AF, Rincón OA, Arango LB, Reutovich AA, Smith GL, Giraldo MA, Bou-Abdallah F, Calderón JC. Calibration of mammalian skeletal muscle Ca 2+ transients recorded with the fast Ca 2+ dye Mag-Fluo-4. Biochim Biophys Acta Gen Subj 2021; 1865:129939. [PMID: 34082059 DOI: 10.1016/j.bbagen.2021.129939] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/12/2021] [Accepted: 05/25/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Mag-Fluo-4 is increasingly employed for studying Ca2+ signaling in skeletal muscle; however, the lack of information on the Ca2+-Mag-Fluo-4 reaction limits its wider usage. METHODS Fluorescence and isothermal titration calorimetry (ITC) experiments were performed to determine the binding stoichiometry (n) and thermodynamics (enthalpy (ΔH) and entropy (ΔS) changes), as well as the in vitro and in situ Kd of the Ca2+-Mag-Fluo-4 reaction. Rate constants (kon, koff), fluorescence maximum (Fmax), minimum (Fmin), and the dye compartmentalization were also estimated. Experiments in cells used enzymatically dissociated flexor digitorum brevis fibres of C57BL6, adult mice, loaded at room temperature for 8 min, with 6 μM Mag-Fluo-4, AM, and permeabilized with saponin or ionomycin. All measurements were done at 20 °C. RESULTS The in vitro fluorescence assays showed a binding stoichiometry of 0.5 for the Ca2+/Mag-Fluo-4 (n = 5) reaction. ITC results (n = 3) provided ΔH and ΔS values of 2.3 (0.7) kJ/mol and 97.8 (5.9) J/mol.K, respectively. The in situ Kd was 1.652 × 105μM2(n = 58 fibres, R2 = 0.99). With an Fmax of 150.9 (8.8) A.U. (n = 8), Fmin of 0.14 (0.1) A.U. (n = 10), and ΔF of Ca2+ transients of 8.4 (2.5) A.U. (n = 10), the sarcoplasmic [Ca2+]peak reached 22.5 (7.8) μM. Compartmentalized dye amounted to only 1.1 (0.7)% (n = 10). CONCLUSIONS Two Mag-Fluo-4 molecules coalesce around one Ca2+ ion, in an entropy-driven, very low in situ affinity reaction, making it suitable to reliably track the kinetics of rapid muscle Ca2+ transients. GENERAL SIGNIFICANCE Our results may be relevant to the quantitative study of Ca2+ kinetics in many other cell types.
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Affiliation(s)
- Andrés F Milán
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin, Colombia
| | - Oscar A Rincón
- Biophysics Group, Institute of Physics, University of Antioquia, Medellin, Colombia
| | - Leidy B Arango
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin, Colombia
| | - Aliaksandra A Reutovich
- Department of Chemistry, The State University of New York at Potsdam (SUNY Potsdam), New York, NY, USA
| | - Gideon L Smith
- Department of Chemistry, The State University of New York at Potsdam (SUNY Potsdam), New York, NY, USA
| | - Marco A Giraldo
- Biophysics Group, Institute of Physics, University of Antioquia, Medellin, Colombia
| | - Fadi Bou-Abdallah
- Department of Chemistry, The State University of New York at Potsdam (SUNY Potsdam), New York, NY, USA.
| | - Juan C Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellin, Colombia.
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Calderón JC, Aguirre-Acevedo D, Montoya E, Yepes-Calderón M, Trillos C, Peña M, Sánchez YL, Milán AF, Granados S, Valbuena L, Montoya I, Aristizábal JC, Narvaez-Sanchez R, Gallo-Villegas J. High-intensity Interval Training Low-volume Vs Moderate-intensity Continuous Aerobic Training On Insulin Resistance In Metabolic Syndrome. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000670072.24645.ac] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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López R, Bolaños P, Guillén A, Fernández MC, Ramos M, Granados S, Milán AF, Caputo C, Alvarado-Castillo C, Estrada O, Calderón JC. Pomolic acid reduces contractility and modulates excitation-contraction coupling in rat cardiomyocytes. Eur J Pharmacol 2019; 851:88-98. [PMID: 30771349 DOI: 10.1016/j.ejphar.2019.02.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 01/31/2019] [Accepted: 02/12/2019] [Indexed: 10/27/2022]
Abstract
Pomolic acid (PA) isolated from Licania pittieri has hypotensive effects in rats, inhibits human platelet aggregation and elicits endothelium-dependent relaxation in rat aortic rings. The present study was designed to investigate the effects of PA on cardiomyocytes. Trabeculae and enzymatically isolated cardiomyocytes from rats were used to evaluate the concentration-dependent effects of PA on cardiac muscle tension and excitation-contraction coupling (ECC) by recording Ca2+ transients reported with Fluo-3 and Fura-2, as well as L-type Ca2+ currents (LTCC). PA reduced the contractile force in rat cardiac trabeculae with an EC50 = 14.3 ± 2.4 μM. PA also reduced the amplitude of Ca2+ transients in a concentration-dependent manner, with an EC50 = 10.5 ± 1.3 μM, without reducing sarcoplasmic reticulum (SR) Ca2+ loading. PA decreased the half width of the Ca2+ transient by 31.7 ± 3.3% and increased the decay time and decay time constant (τ) by 7.6 ± 2.7% and 75.6 ± 3.7%, respectively, which was associated with increased phospholamban (PLN) phosphorylation. PA also reversibly reduced the macroscopic LTCC in the cardiomyocyte membrane, but did not demonstrate any effects on skeletal muscle ECC. In conclusion, PA reduces LTCC, Ca2+ transients and cardiomyocyte force, which along with its vasorelaxant effects explain its hypotensive properties. Increased PLN phosphorylation protected the SR from Ca2+ depletion. Considering the effects of PA on platelet aggregation and the cardiovascular system, we propose it as a new potential, multitarget cardiovascular agent with a demonstrated safety profile.
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Affiliation(s)
- Rubén López
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Pura Bolaños
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Alis Guillén
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Marbely C Fernández
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Magaly Ramos
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Sergio Granados
- Physiology and Biochemistry Research Group-PHYSIS, Department of Physiology and Biochemistry, Faculty of Medicine, University of Antioquia, Medellín, Colombia
| | - Andrés F Milán
- Physiology and Biochemistry Research Group-PHYSIS, Department of Physiology and Biochemistry, Faculty of Medicine, University of Antioquia, Medellín, Colombia
| | - Carlo Caputo
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Claudia Alvarado-Castillo
- Laboratory of Hemostasis and Vascular Genetics, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Omar Estrada
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Juan C Calderón
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela; Physiology and Biochemistry Research Group-PHYSIS, Department of Physiology and Biochemistry, Faculty of Medicine, University of Antioquia, Medellín, Colombia.
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