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Shamas S, Khan SUH, Khan MY, Shabbir N, Zubair H, Shafqat S, Wahab F, Shahab M. Fasting induced kisspeptin signaling suppression is regulated by glutamate mediated cues in adult male rhesus macaque (Macaca mulatta). Neuropeptides 2015; 52:39-45. [PMID: 26138506 DOI: 10.1016/j.npep.2015.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [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: 02/03/2015] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 11/18/2022]
Abstract
Kisspeptin signaling is suppressed by short term fasting. It has been reported that hypothalamic Kiss1 and Kiss1r mRNA expression decreased after 48h of fasting in male rhesus monkey. But the mechanism involved in the reduction of kisspeptin signaling after 48h of fasting is unknown. Recent studies have suggested the role of afferent excitatory and inhibitory pathways in the regulation of kisspeptin neurons. Therefore, this study was designed to observe the changes in the glutamate and GABA signaling during fed and 48h fasting states by performing immunofluorescence to examine the interaction of kisspeptin neurons with NR1 subunit of NMDA receptors and by performing SYBR green qRT-PCR to measure and quantify the levels of Kiss1, Kiss1r, NR1 and GAD67 mRNA in the POA and MBH of adult male rhesus macaque (Macaca mulatta) during 48h of fasting (n=2) and fed ad libitum (n=2). Plasma testosterone (p<0.05) and blood glucose levels were significantly (p<0.001) decreased after short term fasting. Our results clearly showed that expression of hypothalamic Kiss1, Kiss1r and NR1 mRNA was significantly (p<0.05) reduced in adult male rhesus monkeys which were fasted for 48h as compared to those which were fed ad libitum. There was no clear difference in the GAD67 mRNA contents between the two groups. Number of kisspeptin neurons and the interactions of kisspeptin neurons with NR1 were significantly (p<0.05) reduced after 48h fasting. These observations suggest that decreased kisspeptin signaling during fasting may occur due to reduction in glutamatergic inputs to kisspeptin neurons. Our results also suggest that fasting induced suppression of kisspeptin signaling is not mediated through GABAergic neurons.
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Affiliation(s)
- Shazia Shamas
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Saeed-Ul-Hassan Khan
- Department of Pathology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Muhammad Yousaf Khan
- Department of Pathology, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Nadia Shabbir
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Hira Zubair
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Saira Shafqat
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Fazal Wahab
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Shahab
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
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Hui H, McHugh D, Hannan M, Zeng F, Xu SZ, Khan SUH, Levenson R, Beech DJ, Weiss JL. Calcium-sensing mechanism in TRPC5 channels contributing to retardation of neurite outgrowth. J Physiol 2006; 572:165-72. [PMID: 16469785 PMCID: PMC1779652 DOI: 10.1113/jphysiol.2005.102889] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The calcium- and sodium-permeable transient receptor potential channel TRPC5 has an inhibitory role in neuronal outgrowth but the mechanisms governing its activity are poorly understood. Here we propose a mechanism involving the neuronal calcium sensor-1 (NCS-1) protein. Inhibitory mutants of TRPC5 and NCS-1 enhance neurite outgrowth similarly. Mutant NCS-1 does not inhibit surface-expression of TRPC5 but generally suppresses channel activity, irrespective of whether it is evoked by carbachol, store depletion, lanthanides or elevated intracellular calcium. NCS-1 and TRPC5 are in the same protein complex in rat brain and NCS-1 directly binds to the TRPC5 C-terminus. The data suggest protein-protein interaction between NCS-1 and TRPC5, and involvement of this protein complex in retardation of neurite outgrowth.
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Affiliation(s)
- Hui Hui
- Institute of Membrane and Systems Biology, Garstang Building, University of Leeds, Leeds LS2 9JT, UK
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