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Carrasco RA, Bogle OA, Ratto MH, Ulloa-Leal C, Mamani-Cato RH, Adams GP. Predictive characteristics of male fertility in alpacas with special reference to seminal NGF. Theriogenology 2024; 216:177-184. [PMID: 38185017 DOI: 10.1016/j.theriogenology.2023.12.033] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 12/28/2023] [Accepted: 12/28/2023] [Indexed: 01/09/2024]
Abstract
Recent studies document the LH-releasing pathway of nerve growth factor (NGF) in male camelids and that the LH response to seminal NGF is associated with elevated plasma testosterone concentration. Results provide rationale for the hypothesis that NGF in semen is associated with male fertility. In Experiment 1, the association between the amount of NGF in the ejaculate and characteristics of the male reproductive system was examined in alpacas. The concentration of NGF was measured by radioimmunoassay in semen samples collected from male alpacas (n = 47) and correlated with sperm morphology and motility, and measurements of the male reproductive anatomy. Most ejaculates had NGF concentrations that, based on previous studies, triggered ovulation in female camelids, however, we only found a positive correlation between NGF concentration with sperm concentration, thread formation and total NGF, and a negative correlation with pH. In Experiment 2, a retrospective analysis was carried out to determine if breeding performance during the previous season was related to recent concentrations of seminal NGF in male alpacas (n = 22). Birth rates tended to be correlated with sperm concentration and total amount of NGF in the ejaculate (P = 0.09). Experiment 3 was a prospective study to determine the relationship between seminal NGF (n = 8 male alpacas) and ovulation and pregnancy rates in a breeding trial. No association was detected between seminal NGF concentration and ovulation rate, pregnancy rate, or LH response in the female. We conclude that among the breeding males used in our study, the abundance of seminal NGF was correlated with sperm concentration and thread formation, however, it was not predictive of male fertility in alpacas. Examination of males not previously selected as breeding stock may be expected to include a broader range of seminal NGF and provide a more comprehensive understanding of the relationship between seminal NGF and male fertility.
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Affiliation(s)
- R A Carrasco
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada; Department of Obstetrics, Gynecology and Reproductive Science, University of California San Diego, 9500 Gilman drive, La Jolla, CA, USA
| | - O A Bogle
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - M H Ratto
- Department of Animal Science, Universidad Austral de Chile, Valdivia, Chile
| | - C Ulloa-Leal
- Department of Animal Science, Universidad Austral de Chile, Valdivia, Chile
| | - R H Mamani-Cato
- Estacion Experimental Agraria Illpa, Dirección de Desarrollo Tecnológico Agrario, Instituto Nacional de Innovación Agraria (INIA), Rinconada Salcedo s/n Km 22 Carretera Puno - Juliaca, Paucarcolla, Puno, Puno, 21000, Peru
| | - G P Adams
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, S7N 5B4, Canada.
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Carrasco RA, Salih AK, Garcia MD, Khozeimeh ES, Adams GP, Phenix CP, Price EW. Development and Biodistribution of a Nerve Growth Factor Radioactive Conjugate for PET Imaging. Mol Imaging Biol 2023; 25:977-988. [PMID: 36692661 DOI: 10.1007/s11307-023-01805-w] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/16/2023] [Accepted: 01/16/2023] [Indexed: 01/25/2023]
Abstract
PURPOSE The purpose of these studies was to develop a nerve growth factor (NGF) radiometal-chelator conjugate to determine the biodistribution and brain uptake of NGF by positron emission tomography/computerized tomography (PET-CT). PROCEDURES Purified NGF from llama seminal plasma was conjugated with FITC, and the chelator NOTA or DFO. NGF conjugates were evaluated for bioactivity. NOTA- and DFO-conjugated NGF were radiolabeled with gallium-68 or zirconium-89 ([68 Ga]GaCl3, half-life = 68 min; [89Zr]Zr(oxalate)4, half-life = 3.3 days). [89Zr]Zr-NGF was evaluated for biodistribution (0.5, 1, or 24 h), PET imaging (60 min), and brain autoradiography in mice. RESULTS Cell-based in vitro assays confirmed that the NGF conjugates maintained NGF receptor-binding and biological activity. Zirconium-89 and gallium-68 radiolabeling showed a high efficiency; however, only[89Zr]Zr-NGF was stable in vitro. Biodistribution studies showed that, as with most small proteins < 70 kDa, [89Zr]Zr-NGF uptake was predominantly in the kidney and was cleared rapidly with almost complete elimination of NGF at 24 h. Dynamic PET imaging from 0-60 min showed a similar pattern to ex vivo biodistribution with some transient liver uptake. Interestingly, although absolute brain uptake was very low, at 24 h after treatment, cerebral cortex uptake was higher than any other brain area examined and blood. CONCLUSIONS We conclude that conjugation of DFO to NGF through a thiourea linkage allows effective radiolabeling with zirconium-89 while maintaining NGF bioactivity. Following intravenous administration, the radiolabeled NGF targets non-neuronal tissues (e.g., kidney, liver), and although absolute brain uptake was very low, the brain uptake that was observed was restricted to the cortex.
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Affiliation(s)
- R A Carrasco
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK, S7N5B4, Canada
| | - A K Salih
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada
| | - M Dominguez Garcia
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada
| | - E S Khozeimeh
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada
| | - G P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK, S7N5B4, Canada
| | - C P Phenix
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada.
| | - E W Price
- Department of Chemistry, College of Arts and Science, University of Saskatchewan, 110 Science Place, Saskatoon, SK, S7N5C9, Canada.
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Carrasco RA, Breen KM. Allostasis in Neuroendocrine Systems Controlling Reproduction. Endocrinology 2023; 164:bqad125. [PMID: 37586095 PMCID: PMC10461221 DOI: 10.1210/endocr/bqad125] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/08/2023] [Accepted: 08/10/2023] [Indexed: 08/18/2023]
Abstract
Allostasis provides a supporting role to the homeostatic control of biological variables in mammalian species. While the concept of homeostasis is related to the control of variables within a set point or range that are essential to life, allostasis refers to systems that facilitate adaptation to challenges that the organism faces and the new requirements for survival. Essential for such adaptation is the role played by the brain in eliciting neural and neuroendocrine responses. Reproductive function is fundamental for the survival of species but is costly in energetic terms and requires a synchrony with an ever-changing environment. Thus, in many species reproductive function is blocked or delayed over immediate challenges. This review will cover the physiological systems and neuroendocrine pathways that supply allostatic control over reproductive neuroendocrine systems. Light, hypoxia, temperature, nutrition, psychosocial, and immune mediators influence the neuroendocrine control of reproductive functions through pathways that are confluent at the paraventricular nucleus; however, understanding of the integrative responses to these stimuli has not been clarified. Likely, the ultimate consequence of these allostatic mechanisms is the modification of kisspeptin and gonadotropin-releasing hormone neuronal activity, thus compromising reproduction function in the short term, while preserving species survivability.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0674, USA
| | - Kellie M Breen
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0674, USA
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Carrasco RA, Pezo S, Zwiefelhofer EM, Lanigan EE, Singh J, Berland MA, Ulloa-Leal C, Ratto MH, Adams GP. Is seminal nerve growth factor-induced luteinizing hormone release in camelids mediated at the hypothalamus? Reproduction 2023; 165:395-405. [PMID: 36757313 DOI: 10.1530/rep-22-0331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 02/09/2023] [Indexed: 02/10/2023]
Abstract
In brief Seminal nerve growth factor induces ovulation in camelids by influencing the secretion of gonadotrophin-releasing hormone (GnRH) into the portal vessels of the pituitary gland. We show that the nerve growth factor-induced release of GnRH is not mediated directly through interaction with hypothalamic neurons. Abstract Ovulation in camelids is triggered by seminal nerve growth factor (NGF). The mechanism of action of NGF appears to occur via the central nervous system. In this study, we tested the hypothesis that NGF acts in the hypothalamus to induce GnRH release. To determine if NGF-induced ovulation is associated with a rise in NGF concentrations in the cerebrospinal fluid (CSF), llamas were i) mated with an urethrostomized male, ii) mated with intact male, or given intrauterine iii) seminal plasma or i.v.) saline (Experiment 1). To characterize the luteinizing hormone (LH) response after central vs peripheral administration, llamas were treated with saline (negative control) or NGF either by i.v. or intracerebroventricular (ICV) administration (Experiment 2). To determine the role of kisspeptin, the effect of ICV infusion of a kisspeptin receptor antagonist on NGF-induced LH secretion and ovulation was tested in llamas (Experiment 3). In Experiment 1, a surge in circulating concentrations of LH was detected only in llamas mated with an intact male and those given intrauterine seminal plasma, but no changes in CSF concentrations of NGF were detected. In Experiment 2, peripheral administration (i.v.) of NGF induced an LH surge and ovulation, whereas no response was detected after central (ICV) administration. In Experiment 3, the kisspeptin receptor antagonist had no effect on the LH response to NGF. In conclusion, results did not support the hypothesis that NGF-induced ovulation is mediated via a trans-synaptic pathway within the hypothalamus, but rather through a releasing effect on tanycytes at the median eminence.
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Affiliation(s)
- Rodrigo A Carrasco
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Sergio Pezo
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Eric M Zwiefelhofer
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Emily E Lanigan
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Jaswant Singh
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Marco A Berland
- Escuela de Medicina Veterinaria, Facultad de Recursos Naturales, Universidad Catolica de Temuco, Temuco, Chile
| | - Cesar Ulloa-Leal
- Instituto de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Marcelo H Ratto
- Instituto de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Gregg P Adams
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Carrasco RA, Hutt KD, McKenzie CM, Adams GP. Granulosa cell tumour in a llama (Lama glama). Reprod Domest Anim 2023; 58:459-464. [PMID: 36385721 DOI: 10.1111/rda.14296] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 11/09/2022] [Accepted: 11/13/2022] [Indexed: 11/19/2022]
Abstract
Hormonally active tumours are characterized by production and secretion of hormones, irrespective of endogenous feedback mechanisms. An adult llama had exuberant oestrous behaviour, infertility, elevated concentrations of oestradiol and a large ovarian mass. Necropsy revealed the presence of two large abdominal masses, one effacing the right ovary and one in the mesocolon. Considering the clinical and histopathological findings, we conclude that the llama was affected by a granulosa cell tumour. The case suggests that granulosa cell tumours in camelids are hormonally active, and the clinical presentation resembles that of other large animal species. To our knowledge, this is the first case report of an oestrogen-producing, metastatic granulosa cell tumour in a llama.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Kylie D Hutt
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Christina M McKenzie
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Leonardi CEP, Carrasco RA, Dias FCF, Zwiefelhofer EM, Adams GP, Singh J. Mechanism of LH release after peripheral administration of kisspeptin in cattle. PLoS One 2022; 17:e0278564. [PMID: 36459509 PMCID: PMC9718405 DOI: 10.1371/journal.pone.0278564] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 11/18/2022] [Indexed: 12/04/2022] Open
Abstract
Kisspeptin modulates GnRH secretion in mammals and peripheral administration of 10-amino acid fragment of kisspeptin (Kp10) induces LH release and ovulation in cattle. Experiments were done to determine if iv administration of kisspeptin will activate GnRH neurons (i.e., after crossing the blood-brain barrier) and if pre-treatment with a GnRH receptor blocker will alter kisspeptin-induced LH release (from gonadotrophs) and ovulation. In Experiment 1, cows (n = 3 per group) were given human-Kisspeptin10 (hKp10; 3 x 15 mg iv at 60-min intervals) or normal saline and euthanized 150 min after treatment was initiated. Every 20th free-floating section (50 μm thickness) from the preoptic area to hypothalamus was double immunostained to colocalize GnRH- (DAB) and activated neurons (cFOS; Nickel-DAB). Kisspeptin induced plasma LH release from 15 to 150 min (P = 0.01) but the proportion of activated GnRH neurons did not differ between groups (5.8% and 3.5%, respectively; P = 0.11). Immunogold electron microscopy detected close contacts between kisspeptin fibers and GnRH terminals in the median eminence. In Experiment 2, pubertal heifers (n = 5 per group) were treated with 1) hKp10 iv, 2) Cetrorelix (GnRH antagonist; im) + hKp10 iv or 3) saline on Day 6 of the follicular wave under low-progesterone condition. A rise in plasma LH concentration was detected from 15 to 240 min in the hKp10 group but not in cetrorelix or control group (P<0.001). Ovulations were detected only in the hKp10 group (4/5; P = 0.02). Cetrorelix treatment was associated with regression of the preovulatory dominant follicle and emergence of a new follicular wave 3.4±0.75 days after the treatment in all five heifers. Results support the hypothesis that the effect of peripheral kisspeptin is mediated downstream of GnRH synthesis and does not involve GnRH-independent LH release from gonadotrophs. Peripheral kisspeptin may release pre-synthesized GnRH from the nerve terminals in areas outside the blood-brain barrier.
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Affiliation(s)
- Carlos E. P. Leonardi
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Rodrigo A. Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Fernanda C. F. Dias
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Eric M. Zwiefelhofer
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Gregg P. Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Jaswant Singh
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
- * E-mail:
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Cho AD, Carrasco RA, Ruz GA. A RUL Estimation System from Clustered Run-to-Failure Degradation Signals. Sensors (Basel) 2022; 22:5323. [PMID: 35891001 PMCID: PMC9318987 DOI: 10.3390/s22145323] [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] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/08/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
The prognostics and health management disciplines provide an efficient solution to improve a system's durability, taking advantage of its lifespan in functionality before a failure appears. Prognostics are performed to estimate the system or subsystem's remaining useful life (RUL). This estimation can be used as a supply in decision-making within maintenance plans and procedures. This work focuses on prognostics by developing a recurrent neural network and a forecasting method called Prophet to measure the performance quality in RUL estimation. We apply this approach to degradation signals, which do not need to be monotonical. Finally, we test our system using data from new generation telescopes in real-world applications.
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Affiliation(s)
- Anthony D. Cho
- Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Santiago 7941169, Chile; (A.D.C.); (R.A.C.)
- Faculty of Sciences, Engineering and Technology, Universidad Mayor, Santiago 7500994, Chile
| | - Rodrigo A. Carrasco
- Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Santiago 7941169, Chile; (A.D.C.); (R.A.C.)
- School of Engineering, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
| | - Gonzalo A. Ruz
- Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Santiago 7941169, Chile; (A.D.C.); (R.A.C.)
- Data Observatory Foundation, Santiago 7941169, Chile
- Center of Applied Ecology and Sustainability (CAPES), Santiago 8331150, Chile
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8
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Carrasco RA, MacPhee DJ, Adams GP. 117 Nerve growth factor in seminal plasma and its association with extracellular vesicles in South American camelids. Reprod Fertil Dev 2021; 34:295-296. [PMID: 35231254 DOI: 10.1071/rdv34n2ab117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- R A Carrasco
- Department of Chemistry, University of Saskatchewan, Saskatoon, SK, Canada
| | - D J MacPhee
- Department of Veterinary Biomedical Sciences, Saskatoon, SK, Canada
| | - G P Adams
- Department of Veterinary Biomedical Sciences, Saskatoon, SK, Canada
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9
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Carrasco RA, Leonardi CE, Hutt K, Singh J, Adams GP. Kisspeptin induces LH release and ovulation in an induced ovulator†. Biol Reprod 2021; 103:49-59. [PMID: 32307518 DOI: 10.1093/biolre/ioaa051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 02/11/2020] [Revised: 03/31/2020] [Accepted: 04/15/2020] [Indexed: 11/14/2022] Open
Abstract
Kisspeptin has been implicated in the ovulatory process of several species of spontaneous ovulators but in only one induced ovulator. In contrast, NGF in semen is the principal trigger of ovulation in other species of induced ovulators-camelids. We tested the hypotheses that kisspeptin induces luteinizing hormone (LH) secretion in llamas through a hypothalamic mechanism, and kisspeptin neurons are the target of NGF in its ovulation-inducing pathway. In Experiment 1, llamas were given either NGF, kisspeptin, or saline intravenously, and LH secretion and ovulation were compared among groups. All llamas treated with NGF (5/5) or kisspeptin (5/5) had an elevation of LH blood concentrations after treatment and ovulated, whereas none of the saline group did (0/5). In Experiment 2, llamas were either pretreated with a gonadotropin-releasing hormone (GnRH) receptor antagonist or saline and treated 2 h later with kisspeptin. Llamas pretreated with saline had elevated plasma LH concentrations and ovulated (6/6) whereas llamas pretreated with cetrorelix did not (0/6). In Experiment 3, we evaluated the hypothalamic kisspeptin-GnRH neuronal network by immunohistochemistry. Kisspeptin neurons were detected in the arcuate nucleus, the preoptic area, and the anterior hypothalamus, establishing synaptic contacts with GnRH neurons. We found no colocalization between kisspeptin and NGF receptors by double immunofluorescence. Functional and morphological findings support the concept that kisspeptin is a mediator of the LH secretory pathway in llamas; however, the role of kisspeptins in the NGF ovulation-inducing pathway in camelids remains unclear since NGF receptors were not detected in kisspeptin neurons in the hypothalamus.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Carlos E Leonardi
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Kylie Hutt
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Jaswant Singh
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
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Carrasco RA, Leonardi CE, Pezo S, Adams GP. Hypothalamic involvement and the role of progesterone in the NGF-induced LH surge pathway. Reproduction 2021; 162:171-179. [PMID: 34128825 DOI: 10.1530/rep-20-0647] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 06/15/2021] [Indexed: 11/08/2022]
Abstract
To elucidate the mechanism by which nerve growth factor (NGF) influences the LH secretory pathway in camelids, a series of experiments were done to determine the involvement of the hypothalamus (Experiment 1), the role of GnRH neurons (Experiment 2), and the effect of progesterone (Experiment 3) on the NGF-induced LH surge and ovulation in llamas. In Experiment 1, the declining phase of the NGF-induced LH surge was used to determine if the decline is a result of pituitary depletion or hypothalamic unresponsiveness. Female llamas were treated with NGF and, 7 h later, assigned to three groups and given a second dose of NGF (n = 5), a dose of GnRH (n = 5), or saline (n = 6). The LH response was attenuated after the second dose of NGF vs GnRH. In Experiment 2, Fos expression (marker of neuronal activation) in GnRH neurons was examined in the hypothalamus of llamas after NGF or saline treatment (n = 3 per group). Despite an LH surge in the NGF group but not in the saline group, no differences were detected between groups in Fos/GnRH co-expression. In Experiment 3, llamas in low-, medium-, and high-plasma progesterone groups (n = 4 per group) were treated with NGF. The NGF-induced LH surge did not differ among treatment groups. Results from the present study show that the induction of a preovulatory LH surge by NGF may be controlled by a novel pathway involving GnRH neuro-terminals downstream of the hypothalamus and is independent of progesterone influence.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western college of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Carlos E Leonardi
- Department of Veterinary Biomedical Sciences, Western college of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Sergio Pezo
- Department of Veterinary Biomedical Sciences, Western college of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western college of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Carrasco RA, Ratto MH, Adams GP. Differential Effects of Estradiol on Reproductive Function in Camelids. Front Vet Sci 2021; 8:646700. [PMID: 33681337 PMCID: PMC7929994 DOI: 10.3389/fvets.2021.646700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 01/28/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Marcelo H Ratto
- Department of Animal Science, Universidad Austral de Chile, Valdivia, Chile
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
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12
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Carrasco RA, Pezo S, Adams GP. Evidence for the LH-releasing pathway of seminal plasma NGF in male camelids. Theriogenology 2021; 164:100-104. [PMID: 33582512 DOI: 10.1016/j.theriogenology.2021.01.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/14/2022]
Abstract
In the female camelid, systemic administration of NGF induces a preovulatory LH surge that results in ovulation, but the effects of seminal NGF in the male are unknown. In the present study, we tested the hypothesis that the LH-releasing pathway of NGF is present in male camelids. In Experiment 1, male llamas and alpacas were treated with NGF or GnRH (n = 2 llamas and 3 alpacas) and blood samples were collected from 1 h before to 3 h after treatment. Plasma LH concentrations increased after treatment in a surge-like fashion in both GnRH- and NGF-treated groups, but concentrations reached a maximum 2.5 times higher and remained elevated for at least 2 h longer in the NGF-treated group (treatment-by-time interaction, P = 0.01). In Experiment 2, we evaluated the LH and testosterone response to NGF vs saline treatment (n = 3 llamas and 3 alpacas). The LH response to NGF was similar to that in Experiment 1, and plasma testosterone concentrations were higher in the NGF group than in the saline group at 2, 4 and 6 h after treatment (P < 0.05). Results support the hypothesis that the LH-releasing pathway for NGF exists in male South American camelids. The LH response to NGF sustained circulating testosterone concentrations in llamas, suggesting a moderate role of NGF in testosterone secretion.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus drive, Saskatoon, S7N5B4, Canada
| | - Sergio Pezo
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus drive, Saskatoon, S7N5B4, Canada
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus drive, Saskatoon, S7N5B4, Canada.
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13
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Carrasco RA, Singh J, Ratto MH, Adams GP. Neuroanatomical basis of the nerve growth factor ovulation-induction pathway in llamas†. Biol Reprod 2020; 104:578-588. [PMID: 33331645 DOI: 10.1093/biolre/ioaa223] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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: 08/08/2020] [Revised: 11/19/2020] [Accepted: 12/12/2020] [Indexed: 12/25/2022] Open
Abstract
The objective of the study was to characterize the anatomical framework and sites of action of the nerve growth factor (NGF)-mediated ovulation-inducing system of llamas. The expression patterns of NGF and its receptors in the hypothalamus of llamas (n = 5) were examined using single and double immunohistochemistry/immunofluorescence. We also compare the expression pattern of the P75 receptor in the hypothalamus of llama and a spontaneous ovulator species (sheep, n = 5). Both NGF receptors (TrkA and P75) were highly expressed in the medial septum and diagonal band of Broca, and populations of TrkA cells were observed in the periventricular and dorsal hypothalamus. Unexpectedly, we found NGF immunoreactive cell bodies with widespread distribution in the hypothalamus but not in areas endowed with NGF receptors. The organum vasculosum of the lamina terminalis (OVLT) and the median eminence displayed immunoreactivity for P75. Double immunofluorescence using vimentin, a marker of tanycytes, confirmed that tanycytes were immunoreactive to P75 in the median eminence and in the OVLT. Additionally, tanycytes were in close association with GnRH and kisspeptin in the arcuate nucleus and median eminence of llamas. The choroid plexus of llamas contained TrkA and NGF immunoreactivity but no P75 immunoreactivity. Results of the present study demonstrate sites of action of NGF in the llama hypothalamus, providing support for the hypothesis of a central effect of NGF in the ovulation-inducing mechanism in llamas.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Jaswant Singh
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Marcelo H Ratto
- Department of Animal Science, Universidad Austral de Chile, Valdivia, Chile
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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14
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Castillo RL, Ibacache M, Cortínez I, Carrasco-Pozo C, Farías JG, Carrasco RA, Vargas-Errázuriz P, Ramos D, Benavente R, Torres DH, Méndez A. Dexmedetomidine Improves Cardiovascular and Ventilatory Outcomes in Critically Ill Patients: Basic and Clinical Approaches. Front Pharmacol 2020; 10:1641. [PMID: 32184718 PMCID: PMC7058802 DOI: 10.3389/fphar.2019.01641] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022] Open
Abstract
Dexmedetomidine (DEX) is a highly selective α2-adrenergic agonist with sedative and analgesic properties, with minimal respiratory effects. It is used as a sedative in the intensive care unit and the operating room. The opioid-sparing effect and the absence of respiratory effects make dexmedetomidine an attractive adjuvant drug for anesthesia in obese patients who are at an increased risk for postoperative respiratory complications. The pharmacodynamic effects on the cardiovascular system are known; however the mechanisms that induce cardioprotection are still under study. Regarding the pharmacokinetics properties, this drug is extensively metabolized in the liver by the uridine diphosphate glucuronosyltransferases. It has a relatively high hepatic extraction ratio, and therefore, its metabolism is dependent on liver blood flow. This review shows, from a basic clinical approach, the evidence supporting the use of dexmedetomidine in different settings, from its use in animal models of ischemia-reperfusion, and cardioprotective signaling pathways. In addition, pharmacokinetics and pharmacodynamics studies in obese subjects and the management of patients subjected to mechanical ventilation are described. Moreover, the clinical efficacy of delirium incidence in patients with indication of non-invasive ventilation is shown. Finally, the available evidence from DEX is described by a group of Chilean pharmacologists and clinicians who have worked for more than 10 years on DEX.
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Affiliation(s)
- Rodrigo L Castillo
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Unidad de Paciente Crítico, Hospital del Salvador, Santiago, Chile
| | - Mauricio Ibacache
- Programa de Farmacología y Toxicología & División de Anestesiología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ignacio Cortínez
- Programa de Farmacología y Toxicología & División de Anestesiología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Catalina Carrasco-Pozo
- Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Jorge G Farías
- Departmento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Francisco Salazar, Chile
| | - Rodrigo A Carrasco
- Departamento de Cardiología, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Patricio Vargas-Errázuriz
- Unidad de Paciente Crítico, Hospital del Salvador, Santiago, Chile.,Unidad de Paciente Crítico Adulto, Clínica Universidad de Los Andes, Santiago, Chile.,Unidad de Paciente Crítico, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Daniel Ramos
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Rafael Benavente
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Daniela Henríquez Torres
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Aníbal Méndez
- Departamento de Medicina Interna Oriente, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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15
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Abstract
An 18-y-old female llama (Lama glama) in Saskatoon, Saskatchewan was examined during a routine herd check, and a mass was detected in the ventral cervical area just below the angle of the jaw. No clinical signs were evident except for the mass and chronic loss of body condition. Postmortem examination revealed bilateral enlargement of the thyroid gland with multiple cysts. Histopathology of the thyroid gland revealed follicular compact-cellular carcinoma lesions, with infiltration of neoplastic thyroid follicular cells in regional lymph nodes.
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences (Carrasco, Leonardi, Adams), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Western College of Veterinary Medicine (Lanigan), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Charles River Laboratories Senneville, Senneville, Quebec, Canada (Verhoef)
| | - Jolanda Verhoef
- Department of Veterinary Biomedical Sciences (Carrasco, Leonardi, Adams), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Western College of Veterinary Medicine (Lanigan), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Charles River Laboratories Senneville, Senneville, Quebec, Canada (Verhoef)
| | - Carlos E P Leonardi
- Department of Veterinary Biomedical Sciences (Carrasco, Leonardi, Adams), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Western College of Veterinary Medicine (Lanigan), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Charles River Laboratories Senneville, Senneville, Quebec, Canada (Verhoef)
| | - Emily E Lanigan
- Department of Veterinary Biomedical Sciences (Carrasco, Leonardi, Adams), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Western College of Veterinary Medicine (Lanigan), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Charles River Laboratories Senneville, Senneville, Quebec, Canada (Verhoef)
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences (Carrasco, Leonardi, Adams), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Western College of Veterinary Medicine (Lanigan), University of Saskatchewan, Saskatoon, Saskatchewan, Canada.,Charles River Laboratories Senneville, Senneville, Quebec, Canada (Verhoef)
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16
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Carrasco RA, Singh J, Adams GP. The relationship between gonadotropin releasing hormone and ovulation inducing factor/nerve growth factor receptors in the hypothalamus of the llama. Reprod Biol Endocrinol 2018; 16:83. [PMID: 30170607 PMCID: PMC6119247 DOI: 10.1186/s12958-018-0402-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/24/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A molecule identical to nerve growth factor, with ovulation-inducing properties has been discovered in the seminal plasma of South American camelids (ovulation-inducing factor/nerve growth factor; OIF/NGF). We hypothesize that the ovulatory effect of OIF/NGF is initiated at the level of the hypothalamus, presumably by GnRH neurons. The objective of the present study was to determine the structural relationship between GnRH neurons and neurons expressing high- and low-affinity receptors for NGF (i.e., TrkA and p75, respectively) in the hypothalamus. METHODS Mature llamas (n = 4) were euthanized and their hypothalamic tissue was fixed, sectioned, and processed for immunohistochemistry on free-floating sections. Ten equidistant sections per brain were double stained for immunofluorescence detection of TrkA and GnRH, or p75 and GnRH. RESULTS Cells immunoreactive to TrkA were detected in most hypothalamic areas, but the majority of cells were detected in the diagonal band of Broca (part of the ventral forebrain) and the supraoptic nuclei and periventricular area. The number of cells immunoreactive to p75 was highest in the diagonal band of Broca and lateral preoptic areas and least in more caudal areas of the hypothalamus (p < 0.05) in a pattern similar to that of TrkA. A low proportion of GnRH neurons were immunoreactive to TrkA (2.5% of total GnRH cells), and no co-localization between GnRH and p75 was detected. GnRH neuron fibers were detected only occasionally in proximity to TrkA immunopositive neurons. CONCLUSIONS Results do not support the hypothesis that the effect of OIF/NGF is driven by a direct interaction with GnRH neurons, but rather provide rationale for the hypothesis that interneurons exist in the hypothalamus that mediate OIF/NGF-induced ovulation.
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Affiliation(s)
- Rodrigo A. Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 campus drive, Saskatoon, Saskatchewan S7N5B4 Canada
| | - Jaswant Singh
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 campus drive, Saskatoon, Saskatchewan S7N5B4 Canada
| | - Gregg P. Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 campus drive, Saskatoon, Saskatchewan S7N5B4 Canada
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17
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Bogle OA, Carrasco RA, Ratto MH, Singh J, Adams GP. Source and localization of ovulation-inducing factor/nerve growth factor in male reproductive tissues among mammalian species†. Biol Reprod 2018; 99:1194-1204. [DOI: 10.1093/biolre/ioy149] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/29/2018] [Indexed: 11/14/2022] Open
Affiliation(s)
- Orleigh A Bogle
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Rodrigo A Carrasco
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Marcelo H Ratto
- Department of Animal Science, Universidad Austral de Chile, Valdivia, Chile
| | - Jaswant Singh
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Gregg P Adams
- Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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18
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Carrasco RA, Singh J, Adams GP. Distribution and morphology of gonadotropin-releasing hormone neurons in the hypothalamus of an induced ovulator - The llama (Lama glama). Gen Comp Endocrinol 2018; 263:43-50. [PMID: 29656045 DOI: 10.1016/j.ygcen.2018.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/23/2018] [Accepted: 04/11/2018] [Indexed: 11/30/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is a decapeptide involved in the regulation of reproduction in all mammals, but the distribution of GnRH neurons within the brain varies widely among species. The objective of the present study was to characterize the number and distribution of GnRH neurons in the hypothalamus and preoptic area of llamas, an induced ovulator. The brains of female llamas (n = 4) were fixed, frozen and sectioned serially every 50 µm in the transverse (coronal) plane. Every 10th section was stained for immunohistochemical detection of GnRH-positive neuron cell bodies and fibers by incubation with 3,3'-diaminobenzidine. The number of counted immunoreactive cells ranged from 222 to 250 (≈241 ± 13 cells in the preoptic area and hypothalamus per animal) and were localized in the medio-basal hypothalamus (44.3%), anterior hypothalamus (27%), preoptic area (14.9%), diagonal band of Broca/medial septum (13.4%), and mammillary area (0.5%). The immunoreactive cells were not localized in specific hypothalamic nuclei, but rather appeared to be distributed diffusely. The highest concentration of immunoreactive neuron fibers was in the median eminence (P < 0.05), but fibers were identified in most of the areas analyzed, including the neurohypophysis. The GnRH neurons within the hypothalamus displayed monopolar (33%), bipolar (39%), and multipolar (28%) morphologies. The bipolar type was most common in the medio-basal region (40%; P < 0.05). We conclude that GnRH neurons and fibers form a network within the anterior and medio-basal hypothalamus of llamas, suggesting the central location of mechanisms controlling reproductive processes in llamas (i.e., induced ovulation).
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Affiliation(s)
- Rodrigo A Carrasco
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.
| | - Jaswant Singh
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.
| | - Gregg P Adams
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.
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19
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Adams GP, Ratto MH, Carrasco RA. Natural and controlled ovulation in South American camelids. Anim Reprod 2018; 15:996-1002. [PMID: 36249856 PMCID: PMC9536045 DOI: 10.21451/1984-3143-ar2018-0033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 05/05/2018] [Indexed: 11/19/2022] Open
Abstract
The four species of New World camelids and 2 species of Old World camelids derived from a common ancestor in North America. The reproductive characteristics, particularly those involving ovarian function and ovulation, are remarkably similar among the 6 living species of camelids, so much so that interspecies hybrids of nearly all possible combinations have been documented. Camelids are induced-ovulators, triggered by an ovulation-inducing factor in seminal plasma. The timing and mechanism of endocrine events leading to ovulation are discussed, as well as the discovery, identification and mode of action of the seminal factor responsible. The applied aspects of our present understanding are discussed with specific reference to controlled induction of ovulation, ovarian synchronization, and superovulation. Emphasis has been given to the literature on llamas and alpacas, with some reference to studies done in wild species of South American camelids and Old World camels.
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20
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Farías JG, Molina VM, Carrasco RA, Zepeda AB, Figueroa E, Letelier P, Castillo RL. Antioxidant Therapeutic Strategies for Cardiovascular Conditions Associated with Oxidative Stress. Nutrients 2017; 9:nu9090966. [PMID: 28862654 PMCID: PMC5622726 DOI: 10.3390/nu9090966] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [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] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 08/17/2017] [Accepted: 08/18/2017] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress (OS) refers to the imbalance between the generation of reactive oxygen species (ROS) and the ability to scavenge these ROS by endogenous antioxidant systems, where ROS overwhelms the antioxidant capacity. Excessive presence of ROS results in irreversible damage to cell membranes, DNA, and other cellular structures by oxidizing lipids, proteins, and nucleic acids. Oxidative stress plays a crucial role in the pathogenesis of cardiovascular diseases related to hypoxia, cardiotoxicity and ischemia-reperfusion. Here, we describe the participation of OS in the pathophysiology of cardiovascular conditions such as myocardial infarction, anthracycline cardiotoxicity and congenital heart disease. This review focuses on the different clinical events where redox factors and OS are related to cardiovascular pathophysiology, giving to support for novel pharmacological therapies such as omega 3 fatty acids, non-selective betablockers and microRNAs.
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Affiliation(s)
- Jorge G Farías
- Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco 4780000, Chile.
| | - Víctor M Molina
- Unidad de Cuidados Intensivos, Hospital de Niños Roberto del Río, Santiago 7500922, Chile.
- Unidad de Cuidados Intensivos Pediátricos, Hospital Clínico Pontificia Universidad Católica de Chile, Santiago 7500922, Chile.
| | - Rodrigo A Carrasco
- Laboratorio de Investigación Biomédica, Departamento de Medicina Interna, Hospital del Salvador, Santiago 7500922, Chile.
- Departamento de Cardiología, Clínica Alemana, Santiago 7500922, Chile.
| | - Andrea B Zepeda
- Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco 4780000, Chile.
| | - Elías Figueroa
- Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco 4780000, Chile.
- Núcleo de Investigación en Producción Alimentaria, BIOACUI, Escuela de Acuicultura, Universidad Católica de Temuco, Temuco 4780000, Chile.
| | - Pablo Letelier
- Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Temuco 4780000, Chile.
- School of Health Sciences, Universidad Católica de Temuco, Temuco 4780000, Chile.
| | - Rodrigo L Castillo
- Laboratorio de Investigación Biomédica, Departamento de Medicina Interna, Hospital del Salvador, Santiago 7500922, Chile.
- Programa de Fisiopatología Oriente, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 7500922, Chile.
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21
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Adams GP, Ratto MH, Silva ME, Carrasco RA. Ovulation-inducing factor (OIF/NGF) in seminal plasma: a review and update. Reprod Domest Anim 2016; 51 Suppl 2:4-17. [DOI: 10.1111/rda.12795] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- GP Adams
- Veterinary Biomedical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon SK Canada
| | - MH Ratto
- Faculty of Veterinary Sciences; Universidad Austral de Chile; Valdivia Chile
| | - ME Silva
- School of Veterinary Medicine; Núcleo de Investigación en Producción Alimentaria; Universidad Católica de Temuco; Temuco Chile
| | - RA Carrasco
- Veterinary Biomedical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon SK Canada
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22
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Castillo RL, Carrasco RA, Alvarez PI, Ruiz M, Luchsinger V, Zunino E, Martínez MA, Avendaño LF. Relationship between severity of adult community-acquired pneumonia and impairment of the antioxidant defense system. Biol Res 2014; 46:207-13. [PMID: 23959020 DOI: 10.4067/s0716-97602013000200013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 05/15/2013] [Indexed: 11/17/2022] Open
Abstract
Oxidant/antioxidant imbalance has been reported in some infectious diseases, including community-acquired pneumonia (CAP). The aim was to assess the antioxidant status in adults with CAP and its relationship with clinical severity at admission. Fifty-nine patients with CAP were enrolled and categorized at admission by the FINE score, from July 2010 to October 2012. In the same period 61 controls were enrolled. Plasma samples were obtained at admission for determination of the ferric reducing ability of plasma (FRAP) and lipid peroxidation (8-isoprostane). Erythrocyte reduced (GSH)/oxidized (GSSG) glutathione, malondialdehyde (MDA) and antioxidant enzyme activity were assessed. Antioxidant status in adults with CAP represented by FRAP and the GSH/GSSG ratio were 16.8% (p=0.03) and 39.7% (p=0.04) lower than control values, respectively. In addition, FRAP values showed a positive correlation with GSH/GSSG ratio (r=0.852; p<0.02; n=59). The CAP group showed greater lipid peroxidation in both plasma and erythrocytes. The FINE score correlated negatively with FRAP (r= -0.718; p<0.05; n=59) and positively with MDA and F2 isoprostane levels (r=0.673; p<0.05; n=59; r=0.892; p<0.01; n=59, respectively). Antioxidant status alterations correlated with clinical severity. The FRAP assay and lipid peroxidation biomarkers may provide a useful parameter for estimating the severity and the clinical outcome of patients with CAP.
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Affiliation(s)
- Rodrigo L Castillo
- Pathophysiology Program, Faculty of Medicine, University of Chile, Chile.
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23
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Streicher KL, Zhu W, Lehmann KP, Georgantas RW, Morehouse CA, Brohawn P, Carrasco RA, Xiao Z, Tice DA, Higgs BW, Richman L, Jallal B, Ranade K, Yao Y. A novel oncogenic role for the miRNA-506-514 cluster in initiating melanocyte transformation and promoting melanoma growth. Oncogene 2011; 31:1558-70. [PMID: 21860416 DOI: 10.1038/onc.2011.345] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Malignant melanoma is the most aggressive form of skin cancer and its incidence has doubled in the last two decades. It represents only 4% of skin cancer cases per year, but causes as many as 74% of skin cancer deaths. Early detection of malignant melanoma is associated with survival rates of up to 90%, but later detection (stage III to stage IV) is associated with survival rates of only 10%. Dysregulation of microRNA (miRNA) expression has been linked to tumor development and progression by functioning either as a tumor suppressor, an oncogene or a metastasis regulator in multiple cancer types. To understand the role of miRNA in the pathogenesis of malignant melanoma and identify biomarkers of metastasis, miRNA expression profiles in skin punches from 33 metastatic melanoma patients and 14 normal healthy donors were compared. We identified a cluster of 14 miRNAs on the X chromosome, termed the miR-506-514 cluster, which was consistently overexpressed in nearly all melanomas tested (30-60 fold, P<0.001), regardless of mutations in N-ras or B-raf. Inhibition of the expression of this cluster as a whole, or one of its sub-clusters (Sub-cluster A) consisting of six mature miRNAs, led to significant inhibition of cell growth, induction of apoptosis, decreased invasiveness and decreased colony formation in soft agar across multiple melanoma cell lines. Sub-cluster A of the miR-506-514 cluster was critical for maintaining the cancer phenotype, but the overexpression of the full cluster was necessary for melanocyte transformation. Our results provide new insights into the functional role of this miRNA cluster in melanoma, and suggest new approaches to treat or diagnose this disease.
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Affiliation(s)
- K L Streicher
- Department of Translational Sciences, MedImmune LLC, Gaithersburg, MD 20878, USA.
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Subramanian AB, Navarro S, Carrasco RA, Marti M, Das S. Role of exogenous inositol and phosphatidylinositol in glycosylphosphatidylinositol anchor synthesis of GP49 by Giardia lamblia. Biochim Biophys Acta 2000; 1483:69-80. [PMID: 10601696 DOI: 10.1016/s1388-1981(99)00171-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although Giardia lamblia trophozoites are unable to carry out de novo phospholipid synthesis, they can assemble complex glycophospholipids from simple lipids and fatty acids acquired from the host. Previously, we have reported that G. lamblia synthesizes GP49, an invariant surface antigen with a glycosylphosphatidylinositol (GPI) anchor. It is therefore possible that myo-inositol (Ins), phosphatidylinositol (PI) and other GPI precursors are obtained from the dietary products of the human small intestine, where the trophozoites colonize. In this report, we have investigated the role of exogenous Ins and PI on GPI anchor synthesis by G. lamblia. The results demonstrate that [(3)H]Ins and PI internalized by trophozoites, metabolically transformed into GlcN(acyl)-PI and downstream GPI molecules. Further investigations suggest that G. lamblia expresses cytidine monophosphate (CMP)-dependent (Mg(2+)-stimulated) and independent (Mn(2+)-stimulated) inositol headgroup exchange enzymes, which are responsible for exchanging free Ins with cellular PI. We observed that 3-deoxy-3-fluoro-D-myo-inositol (3-F-Ins) and 1-deoxy-1-F-scyllo-Ins (1-F-scyllo-Ins), which are considered potent inhibitors of Mn(2+)-stimulated headgroup exchange enzyme, inhibited the incorporation of [(3)H]Ins into PI and GPI molecules significantly, suggesting that CMP-independent (Mn(2+)-stimulated) exchange enzyme may be important for these reactions. However, 3-F-Ins and 1-F-scyllo-Ins were not effective in blocking the incorporation of exogenously supplied [(3)H]PI into GPI glycolipids. Thus, it can be concluded that G. lamblia can use exogenously supplied [(3)H]PI and [(3)H]Ins to synthesize GPI glycolipids of GP49; while PI is directly incorporated into GPI molecules, free Ins is first converted into PI by headgroup exchange enzymes, and this newly formed PI participates in GPI anchor synthesis.
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Affiliation(s)
- A B Subramanian
- Department of Biological Sciences, University of Texas, El Paso, TX 79968-0519, USA
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25
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Lemercier C, To RQ, Carrasco RA, Konieczny SF. The basic helix-loop-helix transcription factor Mist1 functions as a transcriptional repressor of myoD. EMBO J 1998; 17:1412-22. [PMID: 9482738 PMCID: PMC1170489 DOI: 10.1093/emboj/17.5.1412] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.1] [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: 02/06/2023] Open
Abstract
A good model system to examine aspects of positive and negative transcriptional regulation is the muscle-specific regulatory factor, MyoD, which is a basic helix-loop-helix (bHLH) transcription factor. Although MyoD has the ability to induce skeletal muscle terminal differentiation in a variety of non-muscle cell types, MyoD activity itself is highly regulated through protein-protein interactions involving several different co-factors. Here we describe the characterization of a novel bHLH protein, Mist1, and how it influences MyoD function. We show that Mist1 accumulates in myogenic stem cells (myoblasts) and then decreases as myoblasts differentiate into myotubes. Mist1 functions as a negative regulator of MyoD activity, preventing muscle differentiation and the concomitant expression of muscle-specific genes. Mist1-induced inhibition occurs through a combination of mechanisms, including the formation of inactive MyoD-Mist1 heterodimers and occupancy of specific E-box target sites by Mist1 homodimers. Mist1 lacks a classic transcription activation domain and instead possesses an N-terminal repressor region capable of inhibiting heterologous activators. Thus, Mist1 may represent a new class of repressor molecules that play a role in controlling the transcriptional activity of MyoD, ensuring that expanding myoblast populations remain undifferentiated during early embryonic muscle formation.
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Affiliation(s)
- C Lemercier
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-1392, USA
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