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Sadek M, Stover KR, Liu X, Reed MA, Weaver DF, Reid AY. IDO-1 inhibition improves outcome after fluid percussion injury in adult male rats. J Neurosci Res 2024; 102:e25338. [PMID: 38706427 DOI: 10.1002/jnr.25338] [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] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 03/15/2024] [Accepted: 04/19/2024] [Indexed: 05/07/2024]
Abstract
The enzyme indoleamine 2,3 dioxygenase 1 (IDO1) catalyzes the rate-limiting step in the kynurenine pathway (KP) which produces both neuroprotective and neurotoxic metabolites. Neuroinflammatory signals produced as a result of pathological conditions can increase production of IDO1 and boost its enzymatic capacity. IDO1 and the KP have been implicated in behavioral recovery after human traumatic brain injury (TBI), but their roles in experimental models of TBI are for the most part unknown. We hypothesized there is an increase in KP activity in the fluid percussion injury (FPI) model of TBI, and that administration of an IDO1 inhibitor will improve neurological recovery. In this study, adult male Sprague Dawley rats were subjected to FPI or sham injury and received twice-daily oral administration of the IDO1 inhibitor PF-06840003 (100 mg/kg) or vehicle control. FPI resulted in a significant increase in KP activity, as demonstrated by an increased ratio of kynurenine: tryptophan, in the perilesional neocortex and ipsilateral hippocampus 3 days postinjury (DPI), which normalized by 7 DPI. The increase in KP activity was prevented by PF-06840003. IDO1 inhibition also improved memory performance as assessed in the Barnes maze and anxiety behaviors as assessed in open field testing in the first 28 DPI. These results suggest increased KP activity after FPI may mediate neurological dysfunction, and IDO1 inhibition should be further investigated as a potential therapeutic target to improve recovery.
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Affiliation(s)
- Marawan Sadek
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Kurt R Stover
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Xiaojing Liu
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Mark A Reed
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Donald F Weaver
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Division of Neurology, University of Toronto, Toronto, Ontario, Canada
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Aylin Y Reid
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Division of Neurology, University of Toronto, Toronto, Ontario, Canada
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Chaves-Filho A, Eyres C, Blöbaum L, Landwehr A, Tremblay MÈ. The emerging neuroimmune hypothesis of bipolar disorder: An updated overview of neuroimmune and microglial findings. J Neurochem 2024. [PMID: 38504593 DOI: 10.1111/jnc.16098] [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: 10/13/2023] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/21/2024]
Abstract
Bipolar disorder (BD) is a severe and multifactorial disease, with onset usually in young adulthood, which follows a progressive course throughout life. Replicated epidemiological studies have suggested inflammatory mechanisms and neuroimmune risk factors as primary contributors to the onset and development of BD. While not all patients display overt markers of inflammation, significant evidence suggests that aberrant immune signaling contributes to all stages of the disease and seems to be mood phase dependent, likely explaining the heterogeneity of findings observed in this population. As the brain's immune cells, microglia orchestrate the brain's immune response and play a critical role in maintaining the brain's health across the lifespan. Microglia are also highly sensitive to environmental changes and respond to physiological and pathological events by adapting their functions, structure, and molecular expression. Recently, it has been highlighted that instead of a single population of cells, microglia comprise a heterogeneous community with specialized states adjusted according to the local molecular cues and intercellular interactions. Early evidence has highlighted the contribution of microglia to BD neuropathology, notably for severe outcomes, such as suicidality. However, the roles and diversity of microglial states in this disease are still largely undermined. This review brings an updated overview of current literature on the contribution of neuroimmune risk factors for the onset and progression of BD, the most prominent neuroimmune abnormalities (including biomarker, neuroimaging, ex vivo studies) and the most recent findings of microglial involvement in BD neuropathology. Combining these different shreds of evidence, we aim to propose a unifying hypothesis for BD pathophysiology centered on neuroimmune abnormalities and microglia. Also, we highlight the urgent need to apply novel multi-system biology approaches to characterize the diversity of microglial states and functions involved in this enigmatic disorder, which can open bright perspectives for novel biomarkers and therapeutic discoveries.
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Affiliation(s)
- Adriano Chaves-Filho
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Women Health Research Institute, Vancouver, British Columbia, Canada
- Brain Health Cluster at the Institute on Aging & Lifelong Health (IALH), Victoria, British Columbia, Canada
| | - Capri Eyres
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Leonie Blöbaum
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Antonia Landwehr
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Women Health Research Institute, Vancouver, British Columbia, Canada
- Brain Health Cluster at the Institute on Aging & Lifelong Health (IALH), Victoria, British Columbia, Canada
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, British Columbia, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada
- Department of Molecular Medicine, Université Laval, Québec City, Quebec, Canada
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朱 玥, 龚 姝. [Research Progress in the Effect of Sleep Deprivation on Working Memory and Its Mechanisms]. Sichuan Da Xue Xue Bao Yi Xue Ban 2023; 54:240-245. [PMID: 36949679 PMCID: PMC10409174 DOI: 10.12182/20230260304] [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] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Indexed: 03/24/2023]
Abstract
The incidence of sleep deprivation is increasing year by year and people are also paying more attention to the effects of sleep deprivation on the human body and on cognition. In addition, working memory is the foundation of many advanced cognitive functions. Therefore, we reviewed, herein, the relevant research literature on the influence of sleep deprivation on working memory, the relevant influencing factors, and possible mechanisms of action, intending to acquire a more thorough understanding of the effects of sleep deprivation on working memory and to provide evidence for scientific and sound strategies of sleep.
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Affiliation(s)
- 玥 朱
- 四川大学华西护理学院/四川大学华西医院 心脏大血管外科 (成都 610041)West China School of Nursing, Sichuan University/Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu 610041, China
| | - 姝 龚
- 四川大学华西护理学院/四川大学华西医院 心脏大血管外科 (成都 610041)West China School of Nursing, Sichuan University/Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu 610041, China
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Nogueira SSC, Nogueira-Filho SLG, Duarte JMB, Mendl M. Temperament, Plasticity, and Emotions in Defensive Behaviour of Paca (Mammalia, Hystricognatha). Animals (Basel) 2021; 11:293. [PMID: 33498936 DOI: 10.3390/ani11020293] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 02/08/2023] Open
Abstract
Simple Summary The paca (Cuniculus paca), a Neotropical caviomorph rodent, provides the most sought-after game meat in all its range, and it therefore faces high hunting pressure and consequent poor welfare. The species is categorised as having a conservation status of “least concern” and appears resilient to over-hunting by humans, which may be related to individuals’ behavioural characteristics. To investigate this, we submitted captive pacas to temperament (personality) tests designed to assess individual responses to short challenges and to evaluate individuals’ emotional states. Our results showed that paca with a “restless” temperament performed more abnormal behaviour and less exploratory behaviour in a test of defensive behaviour, which elevations in faecal glucocorticoid metabolites indicated to be stressful. Plasticity in defensive behaviour was inferred from changes in behavioural responses and apparently rapid adaptation to different levels of risk. Our results suggest that individual differences and consistency of behavioural responses displayed by paca toward challenges may reflect a generally flexible and successful defensive behavioural response that underpins the paca’s survival, despite the threat of overhunting throughout its range. Abstract Within a species, some individuals are better able to cope with threatening environments than others. Paca (Cuniculus paca) appear resilient to over-hunting by humans, which may be related to the behavioural plasticity shown by this species. To investigate this, we submitted captive pacas to temperament tests designed to assess individual responses to short challenges and judgement bias tests (JBT) to evaluate individuals’ affective states. Results indicated across-time and context stability in closely correlated “agitated”, “fearful” and “tense” responses; this temperament dimension was labelled “restless”. Individual “restless” scores predicted responses to novelty, although not to simulated chasing and capture by humans in a separate modified defence test battery (MDTB). Restless animals were more likely to show a greater proportion of positive responses to an ambiguous cue during JBT after the MDTB. Plasticity in defensive behaviour was inferred from changes in behavioural responses and apparently rapid adaptation to challenge in the different phases of the MDTB. The results indicate that both temperament and behavioural plasticity may play a role in influencing paca responses to risky situations. Therefore, our study highlights the importance of understanding the role of individual temperament traits and behavioural plasticity in order to better interpret the animals’ conservation status and vulnerabilities.
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