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Raymond J, Morin A, Bradley-Garcia M, Plamondon H. Juvenile/Peripubertal Exposure to Omega-3 and Environmental Enrichment Differentially Affects CORT Secretion and Adulthood Stress Coping, Sociability, and CA3 Glucocorticoid Receptor Expression in Male and Female Rats. Nutrients 2024; 16:2350. [PMID: 39064793 PMCID: PMC11279577 DOI: 10.3390/nu16142350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/11/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
In adult rats, omega-3 supplementation through fish oil (FO) and environmental enrichment (EE) have shown beneficial effects on cognition and stress regulation. This study assessed sex-specific effects of FO and EE during adolescence, a period critical for brain maturation, on adulthood coping mechanisms, sociability, and glucocorticoid regulation. An amount of 64 Wistar rats [n = 32/sex; postnatal day (PND) 23] were assigned to supplementation of control soybean oil (CSO) or menhaden fish oil (FO; 0.3 mL/100 g) from PND28 to 47 and exposed to EE or regular cage (RC) housing from PND28 to 58, with their blood corticosterone (CORT) levels being assessed weekly. As adults, exposure to repeated forced swim tests (FSTs; PND90-91) enabled analysis of coping responses, while socioemotional and memory responses were evaluated using the OFT, EPM, SIT, and Y maze tests (PND92-94). Immunohistochemistry determined hippocampal CA1/CA3 glucocorticoid receptor (GR) expression (PND95). CORT secretion gradually increased as the supplementation period elapsed in female rats, while changes were minimal in males. Coping strategies in the FST differed between sexes, particularly in FO-fed rats, where females and males, respectively, favoured floating and tail support to minimise energy consumption and maintain immobility. In the SIT, FO/EE promoted sociability in females, while a CSO diet favoured social recognition in males. Reduced CA3 GR-ir expression was found in FO/RC and CSO/EE rat groups, supporting stress resilience and memory consolidation. Our findings support environment and dietary conditions to exert a sex-specific impact on biobehavioural responses.
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Affiliation(s)
| | | | | | - Hélène Plamondon
- Behavioural Neuroscience Group, School of Psychology, University of Ottawa, 136 Jean-Jacques Lussier, Ottawa, ON K1N 6N5, Canada; (J.R.); (A.M.); (M.B.-G.)
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Short-Term Fish Oil Supplementation during Adolescence Supports Sex-Specific Impact on Adulthood Visuospatial Memory and Cognitive Flexibility. Nutrients 2022; 14:nu14173513. [PMID: 36079771 PMCID: PMC9459882 DOI: 10.3390/nu14173513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022] Open
Abstract
Numerous studies have supported benefits of omega-3 supplementation using Menhaden fish oil (FO) to promote brain maturation and plasticity during critical developmental periods. The goal of this study was to determine sex-specific immediate and delayed impact of adolescent omega-3 supplementation on visuospatial memory and cognitive flexibility. Sixty-four Wistar rats (n = 32 males and females) received daily FO or soybean oil (CSO) supplementation via oral gavage (0.3 mL/100 g body weight) from postnatal day 28–47. The Barnes Maze Test (BMT) was used to measure visuospatial memory and reversal learning trials (RL) determined cognitive flexibility. Juveniles underwent testing immediately after the gavage period, while adults began testing on postnatal day 90. Adult rats showed reduced working memory errors (WME) and gradual decrease in escape latencies compared to juveniles. Importantly, adult FO-supplemented females displayed fewer WME than males, while males’ performance benefited from CSO supplementation. Overall, sex- and supplementation-dependent effects supported a positive impact of FO in female rats only. Our findings support the potential for supplementation limited to the early adolescence period to influence adulthood spatial learning and cognitive flexibility in a sex-specific manner.
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Raymond J, Morin A, Plamondon H. Delivery method matters: omega-3 supplementation by restricted feeding period and oral gavage has a distinct impact on corticosterone secretion and anxious behavior in adolescent rats. Nutr Neurosci 2020; 25:169-179. [DOI: 10.1080/1028415x.2020.1733813] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Julie Raymond
- Behavioural Neuroscience Group, School of Psychology, University of Ottawa, Ottawa, Canada
| | - Alexandre Morin
- Behavioural Neuroscience Group, School of Psychology, University of Ottawa, Ottawa, Canada
| | - Hélène Plamondon
- Behavioural Neuroscience Group, School of Psychology, University of Ottawa, Ottawa, Canada
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Aguiar A, Giaquinto PC. Low cholesterol is not always good: low cholesterol levels are associated with decreased serotonin and increased aggression in fish. Biol Open 2018; 7:bio.030981. [PMID: 30530746 PMCID: PMC6310874 DOI: 10.1242/bio.030981] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The inverse relationship between serum cholesterol and levels of aggression led to the cholesterol-serotonin hypothesis. According to this hypothesis, low dietary cholesterol intake leads to depressed central serotonergic activity, which is associated with increased aggression. Here we present the hypothesis about the evolutionary origins of low cholesterol and aggressive behavior, investigating the relationship between low levels of plasma cholesterol and aggressive behavior in fish. We used Nile tilapia (Oreochromis niloticus), a species of aggressive fish with a clear dominant subordinate relation, as an experimental model. The fish were treated with statin, a cholesterol-lowering drug. Aggressive behavior, brain serotonin (5-HT) concentrations, 5-hydroxyindoleacetic acid (5-HIAA, the major 5-HT metabolite) and plasma cholesterol were analyzed after chronic administration of statin. Our results show that fish treated with statin exhibited reduced plasma cholesterol, reduced telencephalic indexes of 5-HIAA/5-HT and increased aggressive behavior compared to control fish. These results indicate that changes in plasma cholesterol may affect neurochemical processes underlying aggressive behavior in fish, suggesting an evolutionary mechanism conserved among vertebrates. Such mechanisms may be important for the control of aggression in many vertebrate species, not just mammals, as has been demonstrated so far. Summary: Fish treated with statin exhibited reduced plasma cholesterol, reduced telencephalic indexes of 5-HIAA/5-HT and increased aggressive behavior compared with control fish. Such mechanisms may be important for the control of aggression in many vertebrate species.
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Affiliation(s)
- Ariane Aguiar
- Physiology Department, Biosciences Institute, Sao Paulo State University, Sao Paulo 18618-689, Brazil
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Yamamuro Y, Yamaguchi Y, Abe S, Takenaga F. Neurochemical and behavioural impact of C18 fatty acids in male mice postweaning. Exp Biol Med (Maywood) 2013; 238:658-67. [PMID: 23918877 DOI: 10.1177/1535370213489451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Dietary components, particularly essential fatty acids, affect the expression and maintenance of normal physiological phenotypes. However, the influence of C18 fatty acids that are abundantly present in the normal diet is unclear. We focused on the behavioural and neurochemical effects of C18 fatty acids during postweaning development in male mice. An AIN-93G diet supplemented with 8% stearic acid (C18:0), 3% oleic acid (C18:1), 3% linoleic acid (C18:2) or 3% α-linolenic acid (C18:3) was provided from four weeks of age for eight weeks. At 12 weeks of age, novel exploratory behaviour and social interaction tests were carried out. One week after the last behavioural test, the brain of each mouse was removed. The frequency of social interactive behaviour was decreased by approximately 70% in the C18:0 group compared to the basal diet group, but there was no difference in cumulative time. The frequency of social interaction showed a positive correlation to cumulative time in mice fed with the experimental diets except for C18:0. Dietary C18 fatty acids following weaning had no impact on brain fatty acid composition except for the C18:3 diet. Furthermore, the neurochemical properties to be especially noted were that choline acetyltransferase activity was absolutely higher in C18:0 diet-fed mice than in the other groups, especially in the frontal cortex where it was 1.7-fold higher than in the basal diet-fed group. The present results reveal a significant possibility of neurochemical and behavioural effects of dietary fatty acids, and saturated fatty acids are of special importance during the postweaning period.
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Affiliation(s)
- Yutaka Yamamuro
- Department of Animal Science, College of Bioresource Sciences, Nihon University, Fujisawa, Kanagawa 252-0880, Japan.
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Leonard B, Maes M. Mechanistic explanations how cell-mediated immune activation, inflammation and oxidative and nitrosative stress pathways and their sequels and concomitants play a role in the pathophysiology of unipolar depression. Neurosci Biobehav Rev 2011; 36:764-85. [PMID: 22197082 DOI: 10.1016/j.neubiorev.2011.12.005] [Citation(s) in RCA: 595] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 11/24/2011] [Accepted: 12/10/2011] [Indexed: 12/17/2022]
Abstract
This paper reviews that cell-mediated-immune (CMI) activation and inflammation contribute to depressive symptoms, including anhedonia; anxiety-like behaviors; fatigue and somatic symptoms, e.g. illness behavior or malaise; and mild cognitive impairment (MCI). These effects are in part mediated by increased levels of pro-inflammatory cytokines (PICs), e.g. interleukin-1 (IL-1), IL-6 and tumor necrosis factor (TNF)α, and Th-1-derived cytokines, such as IL-2 and interferon (IFN)γ. Moreover, new pathways, i.e. concomitants and sequels of CMI activation and inflammation, were detected in depression: (1) Induction of indoleamine 2,3-dioxygenase (IDO) by IFNγ and some PICs is associated with depleted plasma tryptophan, which may interfere with brain 5-HT synthesis, and increased production of anxiogenic and depressogenic tryptophan catabolites. (2) Increased bacterial translocation may cause depression-like behaviors by activating the cytokine network, oxidative and nitrosative stress (O&NS) pathways and IDO. (3) Induction of O&NS causes damage to membrane ω3 PUFAs, functional proteins, DNA and mitochondria, and autoimmune responses directed against intracellular molecules that may cause dysfunctions in intracellular signaling. (4) Decreased levels of ω3 PUFAs and antioxidants, such as coenzyme Q10, glutathione peroxidase or zinc, are associated with an increased inflammatory potential; more oxidative damage; the onset of specific symptoms; and changes in the expression or functions of brain 5-HT and N-methyl-d-aspartate receptors. (5) All abovementioned factors cause neuroprogression, that is a combination of neurodegeneration, neuronal apoptosis, and lowered neurogenesis and neuroplasticity. It is concluded that depression may be the consequence of a complex interplay between CMI activation and inflammation and their sequels/concomitants which all together cause neuroprogression that further shapes the depression phenotype. Future research should employ high throughput technologies to collect genetic and gene expression and protein data from patients with depression and analyze these data by means of systems biology methods to define the dynamic interactions between the different cell signaling networks and O&NS pathways that cause depression.
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Affiliation(s)
- Brian Leonard
- Pharmacology Department, National University of Ireland, Galway, Ireland
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Hausman D, Mullen Grossman B. Dietary Fats and Obesity. FOOD SCIENCE AND TECHNOLOGY 2008. [DOI: 10.1201/9781420046649.ch24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Affiliation(s)
- Dirk van West
- 1Clinical Research Center for Mental Health (CRC-MH), Antwerp, Belgium
| | - Michael Maes
- 1Clinical Research Center for Mental Health (CRC-MH), Antwerp, Belgium
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Maes M, Christophe A, Delanghe J, Altamura C, Neels H, Meltzer HY. Lowered omega3 polyunsaturated fatty acids in serum phospholipids and cholesteryl esters of depressed patients. Psychiatry Res 1999; 85:275-91. [PMID: 10333380 DOI: 10.1016/s0165-1781(99)00014-1] [Citation(s) in RCA: 319] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Depression is associated with a lowered degree of esterification of serum cholesterol, an increased C20:4omega6/C20:5omega3 ratio and decreases in omega3 fractions in fatty acids (FAs) or in the red blood cell membrane. The aims of the present study were to examine: (i) serum phospholipid and cholesteryl ester compositions of individual saturated fatty acids (SFAs), monounsaturated FAs (MUFAs) and polyunsaturated FAs (PUFAs) in major depressed patients vs. healthy volunteers; (ii) the relationships between the above FAs and lowered serum zinc (Zn), a marker of the inflammatory response in depression; and (iii) the effects of subchronic treatment with antidepressants on FAs in depression. The composition of the FAs was determined by means of thin layer chromatography in conjunction with gas chromatography. Lipid concentrations were assayed by enzymatic colorimetric methods. The oxidative potential index (OPI) of FAs was computed in 34 major depressed inpatients and 14 normal volunteers. Major depression was associated with: increased MUFA and C22:5omega3 proportions and increased C20:4omega6/C20:5omega3 and C22:5omega6/C22:6omega3 ratios; lower C22:4omega6, C20:5omega3 and C22:5omega3 fractions in phospholipids; lower C18:3omega3, C20:5omega3 and total (sigma)omega3 FAs, and higher C20:4omega6/C20:5omega3 and sigmaomega6/sigmaomega3 ratios in cholesteryl esters; lower serum concentrations of phospholipids and cholesteryl esters; and a decreased OPI. In depression, there were significant and positive correlations between serum Zn and C20:5omega3 and C22:6omega3 fractions in phospholipids; and significant inverse correlations between serum Zn and the sigmaomega6/sigmaomega3, C20:4omega6/C20:5omega3, and C22:5omega6/C22:6omega3 ratios in phospholipids. There was no significant effect of antidepressive treatment on any of the FAs. The results show that, in major depression, there is a deficiency of omega3 PUFAs and a compensatory increase in MUFAs and C22:5omega6 in phospholipids. The results suggest that: (i) there is an abnormal metabolism of omega3 PUFAs in depression; (ii) the FA alterations in depression are related to the inflammatory response in that illness; and (iii) the disorders may persist despite successful antidepressant treatment.
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Affiliation(s)
- M Maes
- University Department of Psychiatry, Clinical Research Center for Mental Health, Antwerp, Belgium.
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10
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Abstract
The degree to which fatty acids modulate brain function beyond periods of rapid brain growth is poorly understood. Nevertheless, recent evidence suggests that dietary fatty acid composition influences numerous behaviors including body temperature regulation, pain sensitivity, feeding behavior including macronutrient selection, and cognitive performance. Importantly, alterations are observed in the absence of essential fatty acid (EFA) deficiency, beyond periods of rapid brain development, and at levels similar to those consumed by the North American population. Data suggest that the content of saturated fatty acids (SFAs), and not that of the EFAs, may be the important component of dietary fat mediating macronutrient selection and cognition under these experimental conditions. Yet, a direct role of SFAs in modulating brain functions has not been elucidated. A discussion of potential mechanisms which may directly involve the central nervous system, or may indirectly influence central processes via peripheral pathway(s) is presented.
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Affiliation(s)
- R J Kaplan
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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11
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Grossman BM, Hobbs JK, Edwards GL, Martin RJ. Dietary fat type influences protein consumption in rats given 8-hydroxy-2-(Di-n-propylamino)tetralin. Physiol Behav 1998; 63:745-50. [PMID: 9617994 DOI: 10.1016/s0031-9384(97)00535-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Our previous work indicates that type and level of dietary fat influences selection of protein and carbohydrate diets. Serotonin (5HT) appears to be involved in this feeding behavior. In the present study, we examined the effects of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) on feeding behavior, and fenfluramine on in vitro 5HT and 5-hydroxyindoleacetic acid (5HIAA) release from the brain in rats fed tallow or corn oil. Male, Sprague-Dawley rats were given a diet containing corn oil or tallow for 2 days. In Experiment 1, rats received an injection of 8-OH-DPAT (a 5HT1A agonist) or saline and were then allowed to select from two diets: low protein/high carbohydrate or high protein/low carbohydrate. Prior exposure to tallow caused an increased intake of protein and 8-OH-DPAT blunted this effect. In Experiment 2, the dorsal raphe from rats fed tallow or corn oil was superfused with fenfluramine or vehicle. Superfusates were collected for analysis of 5HT and 5HIAA. Fenfluramine increased serotonin release in tallow-fed animals as compared to basal. These results suggest that serotonin may be involved in mediating tallow's effect on macronutrient selection.
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Affiliation(s)
- B M Grossman
- Department of Foods and Nutrition, University of Georgia, Athens 30602, USA.
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McGee CD, Lieberman P, Greenwood CE. Dietary fatty acid composition induces comparable changes in cardiolipin fatty acid profile of heart and brain mitochondria. Lipids 1996; 31:611-6. [PMID: 8784741 DOI: 10.1007/bf02523831] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The fatty acid profile of cardiolipin (CL) from brain and cardiac mitochondria was measured to determine whether CL isolated from these two tissue sources responded similarly to alterations in dietary fat composition. Male Wistar rats were fed 20% (w/w) diets containing 2 to 12% (w/w) 18:2n-6 for four weeks. Despite higher baseline levels of CL 18:2n-6 in cardiac (54 +/- 1% of total fatty acids) compared to brain (13 +/- 1%) mitochondria, CL 18:2n-6 levels increased in proportion to dietary 18:2 levels. The degree of change in 18:2n-6 was comparable with both tissues showing an approximate 1.5- to 2-fold increase. The time course of changes in CL fatty acid profile was examined in a subsequent experiment in which animals were fed 20% (w/w) fat diets containing either 3 or 15% alpha-linoleate. Changes in cardiac CL 18:1, 18:2n-6, and 22:6n-3 levels were observed within one week of feeding. While statistically significant differences were not observed in brain CL until the second week of feeding, the time course did not differ substantively from that observed in heart. The results from this study suggest that while baseline fatty acid profile of cardiac and neural CL differ, mitochondria from both tissues show comparable sensitivity to changes in dietary fat composition. Furthermore, it would appear that the turnover rate of fatty acids in CL is similar in both tissues.
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Affiliation(s)
- C D McGee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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Maes M, Smith R, Christophe A, Cosyns P, Desnyder R, Meltzer H. Fatty acid composition in major depression: decreased omega 3 fractions in cholesteryl esters and increased C20: 4 omega 6/C20:5 omega 3 ratio in cholesteryl esters and phospholipids. J Affect Disord 1996; 38:35-46. [PMID: 8735157 DOI: 10.1016/0165-0327(95)00092-5] [Citation(s) in RCA: 286] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Recently, there were some reports that major depression may be accompanied by alterations in serum total cholesterol, cholesterol ester and omega 3 essential fatty acid levels and by an increased C20: 4 omega 6/C20: 5 omega 3, i.e., arachidonic acid/eicosapentaenoic, ratio. The present study aimed to examine fatty acid composition of serum cholesteryl esters and phospholipids in 36 major depressed, 14 minor depressed and 24 normal subjects. Individual saturated (e.g., C14:0; C16:0, C18:0) and unsaturated (e.g., C18:1, C18:2, C20:4) fatty acids in phospholipid and cholesteryl ester fractions were assayed and the sums of the percentages of omega 6 and omega 3, saturated, branched chain and odd chain fatty acids, monoenes as well as the ratios omega 6/omega 3 and C20:4 omega 6/C20:5 omega 3 were calculated. Major depressed subjects had significantly higher C20:4 omega 6/C20:5 omega 3 ratio in both serum cholesteryl esters and phospholipids and a significantly increased omega 6/omega 3 ratio in cholesteryl ester fraction than healthy volunteers and minor depressed subjects. Major depressed subjects had significantly lower C18:3 omega 3 in cholesteryl esters than normal controls. Major depressed subjects showed significantly lower total omega 3 polyunsaturated fatty acids in cholesteryl esters and significantly lower C20:5 omega 3 in serum cholesteryl esters and phospholipids than minor depressed subjects and healthy controls. These findings suggest an abnormal intake or metabolism of essential fatty acids in conjunction with decreased formation of cholesteryl esters in major depression.
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Affiliation(s)
- M Maes
- Clinical Research Center, University Department of Psychiatry, Antwerp, Belgium
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Abstract
The debate about possible adverse effects associated with low or lowered serum cholesterol has raised important scientific questions concerning the links between lipids and behaviour. One of the most unexpected findings has been an association between cholesterol-lowering treatment and accidental death. A similar association has also emerged among the prospective cohort studies, with higher-than-expected numbers of suicide deaths in the lowest cholesterol groups. These observations have prompted speculation that behavioural or emotional disturbances could be part of the process linking lipids and accidental death. In this paper, the epidemiological literature is reviewed briefly, then the evidence for depression as a mediating condition is discussed. Two conclusions are drawn from this review of the literature. One is that understanding the relationship between the biology of lipids and the psychobiology of mood is demonstrably an important scientific and public health issue. The second is that the introduction of new treatments or preventive programmes should include a careful evaluation of the psychological as well as the physical effects.
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Affiliation(s)
- J Wardle
- Health Behaviour Unit, Institute of Psychiatry, University of London, UK
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Wang SW, Wang M, Grossman BM, Martin RJ. Effects of dietary fat on food intake and brain uptake and oxidation of fatty acids. Physiol Behav 1994; 56:517-22. [PMID: 7972402 DOI: 10.1016/0031-9384(94)90295-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The present study was designed to investigate (a) whether dietary fat manipulation, quantitatively and/or qualitatively, may influence the transport of fatty acids into the brain and oxidation of fatty acids in the hypothalamus; and (b) if an inhibitor of fatty acid oxidation changed food intake on these diets. Rats were fed for 4 wk 5% or 34% corn oil or tallow diets that were isocaloric and isonitrogenous. It was found that rats fed corn oil diets had significantly higher brain uptake index of palmitate than did rats fed tallow diets. In a second experiment, rats were fed either 30% corn oil or tallow diets and injected with either saline or mercaptoacetate (MA). Both saturated fat diets and mercaptoacetate injection reduced lateral hypothalamic, but not ventromedial hypothalamic fatty acid oxidation. Mercaptoacetate increased food intake only in the corn oil fed rats. It is proposed that these uptake and metabolic changes contribute to alterations in either energy expenditure or feeding behavior.
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Affiliation(s)
- S W Wang
- Department of Foods and Nutrition, University of Georgia, Athens 30602-3622
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McGee CD, Greenwood CE, Cinader B. Dietary fat composition and age affect synaptosomal and retinal phospholipid fatty acid composition in C57BL/6 mice. Lipids 1994; 29:605-10. [PMID: 7815894 DOI: 10.1007/bf02536094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The purpose of this study was (i) to determine whether dietary fat-induced differences in neural and retinal membranes occur when dietary fat treatment is implemented in aged animals and (ii) to characterize the effect of long-term differences in dietary fat on neural and retinal membrane composition. For the first objective, young (six-week-old) and old (95-week-old) mice were randomly assigned to beef tallow (TAL) or soybean oil (SBO) diets for eight weeks. For the second objective, young (four-week-old) mice consumed either TAL or SBO diets for 99 weeks. Young and old mice challenged with a change in dietary fat for an eight-week period showed both diet and age effects on neural and retinal phospholipid fatty acid composition (P < 0.05). In addition, significant diet by age interactions were evident. In mice that consumed TAL and SBO diets throughout their life, only retinal phosphatidylethanolamine (PE) 18:2n-6 and neural phosphatidylserine 22:5n-6, PE 18:2n-6 and phosphatidylcholine 18:2n-6 differed between dietary treatments (P < 0.05). Neither the unsaturation index nor the n-6/n-3 ratio was affected by diet. Neural and retinal phospholipid fatty acid composition were responsive to changes in dietary fat even when the treatment was implemented beyond developmental or post-weanling stages. In contrast, when mice consumed TAL or SBO diets throughout their life, fewer differences in phospholipid fatty acid composition were detected, suggesting that the effect of the dietary treatment was mitigated by aging.
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Affiliation(s)
- C D McGee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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Nakashima Y, Yuasa S, Hukamizu Y, Okuyama H, Ohhara T, Kameyama T, Nabeshima T. Effect of a high linoleate and a high alpha-linolenate diet on general behavior and drug sensitivity in mice. J Lipid Res 1993. [DOI: 10.1016/s0022-2275(20)40751-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Johnston WL, Atkinson JL, Theresa Glanville N. Effect of PCPA or tryptophan on brain serotonin and on consumption of a high protein or high carbohydrate diet by rainbow trout, Oncorhynchus mykiss. J Nutr Biochem 1992. [DOI: 10.1016/0955-2863(92)90017-d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Dyer JR, Greenwood CE. The level of linoleic acid in neural cardiolipin is linearly correlated to the amount of essential fatty acids in the diet of the weanling rat. J Nutr Biochem 1991. [DOI: 10.1016/0955-2863(91)90103-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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20
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Dyer JR, Greenwood CE. Neural 22-carbon fatty acids in the weanling rat respond rapidly and specifically to a range of dietary linoleic to alpha-linolenic fatty acid ratios. J Neurochem 1991; 56:1921-31. [PMID: 1673995 DOI: 10.1111/j.1471-4159.1991.tb03449.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Changing the dietary ratio of the essential fatty acids (EFA), 18:2n6 and 18:3n3, while keeping the amounts of other fatty acids in the diet constant can rapidly and specifically alter the proportions of n6 and n3 22-carbon fatty acids in the brain of the weanling rat. A dietary 18:2n6/18:3n3 ratio of 165 versus 1.8 caused higher n6 and lower n3 22-carbon fatty acid levels, without changing total 22-carbon fatty acid levels, in phosphatidylethanolamine and phosphatidylcholine from several neural membrane fractions. This was apparent after only 2 weeks and showed no sign of plateauing after 12 weeks. Other neural fatty acids were essentially unaffected. The three most abundant 22-carbon fatty acids responded somewhat differently to increments in the dietary 18:2n6/18:3n3 ratio (1.8, 9, 36, and 165). Levels of 22:4n6 increased by similar absolute amounts for each four-fold increase in dietary 18:2n6/18:3n3 ratio; in contrast, the largest absolute changes in 22:5n6 and 22:6n3 levels occurred as the 18:2n6/18:3n3 ratio increased from 36 to 165. This study shows that the 18:2n6/18:3n3 ratio of diets high in fat (40% of energy) and adequate in EFA, both typical of diets in developed countries, can substantially and relatively quickly affect the 22-carbon fatty acids in the brain, even after the rapid accumulation of these fatty acids during neural growth has ceased.
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Affiliation(s)
- J R Dyer
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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McGee CD, Greenwood CE. Effect of qualitative differences in dietary fat on dexfenfluramine mediated depression of food intake and serotonin metabolism. J Nutr Biochem 1991. [DOI: 10.1016/0955-2863(91)90033-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Affiliation(s)
- S M Innis
- Department of Paediatrics, University of British Columbia, Vancouver, Canada
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McGee CD, Greenwood CE. Protein and carbohydrate selection respond to changes in dietary saturated fatty acids but not to changes in essential fatty acids. Life Sci 1990; 47:67-76. [PMID: 2388519 DOI: 10.1016/0024-3205(90)90567-b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We previously reported differences in protein and carbohydrate selection patterns in post-weanling rats fed beef tallow or soybean oil-based diets. Two experiments were designed to determine the characteristic of the dietary fat which mediates the selection behavior. For each experiment, dietary fat was 20% (w/w) of diets and fatty acid profiles were obtained by blending fat sources. Rats were randomly assigned to diets (24% protein, 40% carbohydrate) which varied only in fatty acid composition. After 2 weeks, rats selected from 2 diets with the fat composition previously fed, but varying in their protein and carbohydrate composition (55% protein, 4% carbohydrate and 5% protein, 61% carbohydrate). Experiment 1 was designed to test the effect of relative (omega 6: omega 3 ratios of 1 and 20) and absolute (15% or 4% omega 6, 0.7% or 0.2% omega 3) differences in essential fatty acids on macronutrient selection patterns. Differences in dietary essential fatty acids had no effect on energy intake or the proportion of energy consumed as protein and carbohydrate. Experiment 2 examined the effect of differences in the level of saturated fat (3-10% diet (w/w] on protein and carbohydrate selection. Animals selecting from diets with higher levels of saturated fat consumed more energy as protein and less as carbohydrate than rats selecting from diets with lower levels of saturated fat (p less than 0.0001). Regression analysis was used to examine the relationship between percent protein or carbohydrate energy and classes of dietary fat. The strongest relationship existed between percent dietary saturated fat and percent protein or carbohydrate energy (p less than 0.0001). Polyunsaturated:saturated fat ratio was also weakly associated with percent protein and carbohydrate energy (p less than 0.05). Polyunsaturated, monounsaturated, omega 6 and omega 3 fatty acids were not significantly related to percent protein or carbohydrate energy. These results indicated that protein and carbohydrate selection patterns are altered in response to qualitatively different dietary fatty acids, and that the amount of saturated fat in the diet is the important characteristic of dietary fat mediating the behavioral alteration.
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Affiliation(s)
- C D McGee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Canada
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Abstract
This chapter reviews the two mitochondrial flavin containing isozymes of monoamine oxidase. Section 1, "Biochemistry" discusses assays, substrates and inhibitors, phylogenic and tissue distribution, interactions with lipids, nutritional studies, protein structure, kinetic and chemical mechanistic proposals, and biosynthesis. Section 2, "Inheritance" discusses possible genes involved in expression, genetic studies of platelet MAO-B and fibroblast MAO-A, and chromosomal location. Section 3, "Molecular Genetics" reviews the cloning of their cDNAs, their intra- and interspecies homology and structural inferences made from deduced amino acid sequences. Section 4, "Regulation" gives an overview of levels in development and aging, and effect of drugs. The final section 5, "Role in Human Disease" discusses physiological function and effects of altered levels in humans and animal models including complete absence due to a submicroscopic chromosomal deletion in several human patients.
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Affiliation(s)
- W Weyler
- Molecular Biology Division, VA Medical Center, San Francisco, CA 94121
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Greenwood CE, Winocur G. Learning and memory impairment in rats fed a high saturated fat diet. BEHAVIORAL AND NEURAL BIOLOGY 1990; 53:74-87. [PMID: 2302144 DOI: 10.1016/0163-1047(90)90831-p] [Citation(s) in RCA: 143] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
At the age of 1 month, three separate groups of Long-Evans rats were placed on 20% (w/w) fat (40% of calories) diets high in either saturated fatty acids (lard-based) or polyunsaturated fatty acids (soybean oil-based) or standard laboratory chow (Purina, 4.5% (w/w) fat). After 3 months, all rats were administered three tests of learning and memory--Olton's radial arm maze, a variable-interval delayed alternation task, and the Hebb-Williams maze series. The lard-fed group was impaired on all tests. The soybean oil-fed group was slightly impaired on some measures, relative to the chow-fed group, but consistently performed better than the lard-fed group. The results indicate that a diet high in saturated fatty acids can impair a wide range of learning and memory functions and are in line with biochemical and physiological evidence showing widespread effects of such diets on brain function.
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Affiliation(s)
- C E Greenwood
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
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McGee CD, Greenwood CE. Dietary fat-induced changes in protein and carbohydrate selection are not explained by alterations in neuronal membrane fatty acid composition. Life Sci 1990; 47:933-44. [PMID: 2215075 DOI: 10.1016/0024-3205(90)90540-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We previously showed changes in protein and carbohydrate selection in response to qualitative differences in dietary fat. Alterations in macronutrient selection were specifically related to changes in dietary saturated fat, but not to relative or absolute differences in dietary essential fatty acids. Three experiments were conducted to determine if changes in specific fatty acids in bulk phase neural membranes were associated with differences in macronutrient selection. For each experiment, specific fatty acid profiles were achieved by blending dietary fat sources. Rats consumed 20% (w/w) fat diets varying only in their fatty acid composition. After 2 weeks, rats were challenged with a selection paradigm. Each experiment showed a significant effect of dietary fat on neural membrane fatty acid composition (p less than 0.05) and alterations in individual fatty acids were correlated with changes in dietary fatty acids (p less than 0.05). However, dietary fat had no consistent effect with respect to which particular neural membrane fatty acids were modified, and there was no correlation between changes in specific membrane fatty acids and macronutrient selection. These findings suggest that alteration of specific fatty acids in bulk phase neural membranes do not mediate macronutrient selection behavior.
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Affiliation(s)
- C D McGee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Canada
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