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Jameson AN, Siemann JK, Grueter CA, Grueter B, McMahon DG. Effects of age and sex on photoperiod modulation of nucleus accumbens monoamine content and release in adolescence and adulthood. Neurobiol Sleep Circadian Rhythms 2024; 16:100103. [PMID: 38585223 PMCID: PMC10990739 DOI: 10.1016/j.nbscr.2024.100103] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/22/2024] [Accepted: 03/22/2024] [Indexed: 04/09/2024] Open
Abstract
Day length, or photoperiod, is a reliable environmental cue encoded by the brain's circadian clock that indicates changing seasons and induces seasonal biological processes. In humans, photoperiod, age, and sex have been linked to seasonality in neuropsychiatric disorders, as seen in Seasonal Affective Disorder, Major Depressive Disorder, and Bipolar Disorder. The nucleus accumbens is a key locus for the regulation of motivated behaviors and neuropsychiatric disorders. Using periadolescent and young adult male and female mice, here we assessed photoperiod's effect on serotonin and dopamine tissue content in the nucleus accumbens core, as well as on accumbal synaptic dopamine release and uptake. We found greater serotonin and dopamine tissue content in the nucleus accumbens from young adult mice raised in a Short winter-like photoperiod. In addition, dopamine release and clearance were greater in the nucleus accumbens from young adult mice raised in a Long summer-like photoperiod. Importantly, we found that photoperiod's effects on accumbal dopamine tissue content and release were sex-specific to young adult females. These findings support that in mice there are interactions across age, sex, and photoperiod that impact critical monoamine neuromodulators in the nucleus accumbens which may provide mechanistic insight into the age and sex dependencies in seasonality of neuropsychiatric disorders in humans.
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Affiliation(s)
- Alexis N. Jameson
- Neuroscience Graduate Program, Vanderbilt University, Nashville, TN, 37232, USA
| | - Justin K. Siemann
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
- Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, 37232, USA
| | - Carrie A. Grueter
- Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN 37232, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
| | - BradA. Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
| | - Douglas G. McMahon
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, 37232, USA
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Manz KM, Ghose D, Turner BD, Taylor A, Becker J, Grueter CA, Grueter BA. Calcium-Permeable AMPA Receptors Promote Endocannabinoid Signaling at Parvalbumin Interneuron Synapses in the Nucleus Accumbens Core. Cell Rep 2021; 32:107971. [PMID: 32726634 PMCID: PMC7422922 DOI: 10.1016/j.celrep.2020.107971] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [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] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/21/2020] [Accepted: 07/08/2020] [Indexed: 12/22/2022] Open
Abstract
Synaptic plasticity is a key mechanism of learning and memory. Synaptic plasticity mechanisms within the nucleus accumbens (NAc) mediate differential behavioral adaptations. Feedforward inhibition in the NAc occurs when glutamatergic afferents onto medium spiny neurons (MSNs) collateralize onto fast-spiking parvalbumin (PV)-expressing interneurons (PV-INs), which exert GABAergic control over MSN action potential generation. Here, we find that feedforward glutamatergic synapses onto PV-INs in the NAc core selectively express Ca2+-permeable AMPA receptors (CP-AMPARs). Ca2+ influx by CP-AMPARs on PV-INs triggers long-term depression (LTD) mediated by endocannabinoid (eCB) signaling at presynaptic cannabinoid type-1 (CB1) receptors (CB1Rs). Moreover, CP-AMPARs authorize tonic eCB signaling to negatively regulate glutamate release probability. Blockade of CP-AMPARs in the NAc core in vivo is sufficient to disinhibit locomotor output. These findings elucidate mechanisms by which PV-IN-embedded microcircuits in the NAc undergo activity-dependent shifts in synaptic strength. Manz et al. show that CP-AMPARs are expressed at glutamatergic synapses onto PV-INs but not D1- or D2-expressing MSNs in the NAc core. Ca2+ influx through CP-AMPARs triggers endocannabinoid-dependent tone and synaptic plasticity. Intra-NAc blockade of CP-AMPARs in vivo increases basal locomotion.
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Affiliation(s)
- Kevin M Manz
- Medical Scientist Training Program, Vanderbilt University, Nashville, TN 37232, USA; Neuroscience Graduate Program, Vanderbilt University, Nashville, TN 37232, USA; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Dipanwita Ghose
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Brandon D Turner
- Neuroscience Graduate Program, Vanderbilt University, Nashville, TN 37232, USA
| | - Anne Taylor
- Neuroscience Graduate Program, Vanderbilt University, Nashville, TN 37232, USA
| | - Jennifer Becker
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Carrie A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Brad A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA.
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Turner BD, Smith NK, Manz KM, Chang BT, Delpire E, Grueter CA, Grueter BA. Cannabinoid type 1 receptors in A2a neurons contribute to cocaine-environment association. Psychopharmacology (Berl) 2021; 238:1121-1131. [PMID: 33454843 PMCID: PMC8386588 DOI: 10.1007/s00213-021-05759-1] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 01/06/2021] [Indexed: 12/14/2022]
Abstract
RATIONALE Cannabinoid type 1 receptors (CB1Rs) are widely expressed within the brain's reward circuits and are implicated in regulating drug induced behavioral adaptations. Understanding how CB1R signaling in discrete circuits and cell types contributes to drug-related behavior provides further insight into the pathology of substance use disorders. OBJECTIVE AND METHODS We sought to determine how cell type-specific expression of CB1Rs within striatal circuits contributes to cocaine-induced behavioral plasticity, hypothesizing that CB1R function in distinct striatal neuron populations would differentially impact behavioral outcomes. We crossed conditional Cnr1fl/fl mice and striatal output pathway cre lines (Drd1a -cre; D1, Adora2a -cre; A2a) to generate cell type-specific CB1R knockout mice and assessed their performance in cocaine locomotor and associative behavioral assays. RESULTS Both knockout lines retained typical locomotor activity at baseline. D1-Cre x Cnr1fl/fl mice did not display hyperlocomotion in response to acute cocaine dosing, and both knockout lines exhibited blunted locomotor activity across repeated cocaine doses. A2a-cre Cnr1fl/fl, mice did not express a preference for cocaine paired environments in a two-choice place preference task. CONCLUSIONS This study aids in mapping CB1R-dependent cocaine-induced behavioral adaptations onto distinct striatal neuron subtypes. A reduction of cocaine-induced locomotor activation in the D1- and A2a-Cnr1 knockout mice supports a role for CB1R function in the motor circuit. Furthermore, a lack of preference for cocaine-associated context in A2a-Cnr1 mice suggests that CB1Rs on A2a-neuron inhibitory terminals are necessary for either reward perception, memory consolidation, or recall. These results direct future investigations into CB1R-dependent adaptations underlying the development and persistence of substance use disorders.
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MESH Headings
- Animals
- Cocaine-Related Disorders/psychology
- Conditioning, Operant/drug effects
- Corpus Striatum/drug effects
- Environment
- Male
- Mice
- Mice, Knockout
- Motor Activity/drug effects
- Neurons/drug effects
- Receptor, Adenosine A2A/drug effects
- Receptor, Adenosine A2A/genetics
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Reward
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Affiliation(s)
- Brandon D Turner
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
| | - Nicholas K Smith
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
| | - Kevin M Manz
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
- Medical Scientist Training Program, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Betty T Chang
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
| | - Eric Delpire
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37232, USA
| | - Carrie A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Brad A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA.
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
- Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, 37232, USA.
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37232, USA.
- Anesthesiology Research Division, Vanderbilt University School of Medicine, 2213 Garland Avenue, P435H MRB IV, Nashville, TN, 37232-0413, USA.
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Manz KM, Becker JC, Grueter CA, Grueter BA. Histamine H 3 Receptor Function Biases Excitatory Gain in the Nucleus Accumbens. Biol Psychiatry 2021; 89:588-599. [PMID: 33012522 PMCID: PMC7865000 DOI: 10.1016/j.biopsych.2020.07.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Histamine (HA), a wake-promoting monoamine implicated in stress-related arousal states, is synthesized in histidine decarboxylase-expressing hypothalamic neurons of the tuberomammillary nucleus. Histidine decarboxylase-containing varicosities diffusely innervate striatal and mesolimbic networks, including the nucleus accumbens (NAc). The NAc integrates diverse monoaminergic inputs to coordinate motivated behavior. While the NAc expresses various HA receptor subtypes, mechanisms by which HA modulates NAc circuit dynamics are undefined. METHODS Using male D1tdTomato transgenic reporter mice, whole-cell patch-clamp electrophysiology, and input-specific optogenetics, we employed a targeted pharmacological approach to interrogate synaptic mechanisms recruited by HA signaling at glutamatergic synapses in the NAc. We incorporated an immobilization stress protocol to assess whether acute stress engages these mechanisms at glutamatergic synapses onto D1 receptor-expressing [D1(+)] medium spiny neurons (MSNs) in the NAc core. RESULTS HA negatively regulates excitatory gain onto D1(+)-MSNs via presynaptic H3 receptor-dependent long-term depression that requires Gβγ-directed Akt-GSK3β signaling. Furthermore, HA asymmetrically regulates glutamatergic transmission from the prefrontal cortex and mediodorsal thalamus, with inputs from the prefrontal cortex undergoing robust HA-induced long-term depression. Finally, we report that acute immobilization stress attenuates this long-term depression by recruiting endogenous H3 receptor signaling in the NAc at glutamatergic synapses onto D1(+)-MSNs. CONCLUSIONS Stress-evoked HA signaling in the NAc recruits H3 heteroreceptor signaling to shift thalamocortical input onto D1(+)-MSNs in the NAc. Our findings provide novel insight into an understudied neuromodulatory system within the NAc and implicate HA in stress-associated physiological states.
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Affiliation(s)
- Kevin M Manz
- Medical Scientist Training Program, Vanderbilt University, Nashville, Tennessee; Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jennifer C Becker
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Carrie A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Brad A Grueter
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee; Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, Tennessee; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee; Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee.
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Folkes OM, Báldi R, Kondev V, Marcus DJ, Hartley ND, Turner BD, Ayers JK, Baechle JJ, Misra MP, Altemus M, Grueter CA, Grueter BA, Patel S. An endocannabinoid-regulated basolateral amygdala-nucleus accumbens circuit modulates sociability. J Clin Invest 2020; 130:1728-1742. [PMID: 31874107 DOI: 10.1172/jci131752] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [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: 07/14/2019] [Accepted: 12/18/2019] [Indexed: 12/24/2022] Open
Abstract
Deficits in social interaction (SI) are a core symptom of autism spectrum disorders (ASDs); however, treatments for social deficits are notably lacking. Elucidating brain circuits and neuromodulatory signaling systems that regulate sociability could facilitate a deeper understanding of ASD pathophysiology and reveal novel treatments for ASDs. Here we found that in vivo optogenetic activation of the basolateral amygdala-nucleus accumbens (BLA-NAc) glutamatergic circuit reduced SI and increased social avoidance in mice. Furthermore, we found that 2-arachidonoylglycerol (2-AG) endocannabinoid signaling reduced BLA-NAc glutamatergic activity and that pharmacological 2-AG augmentation via administration of JZL184, a monoacylglycerol lipase inhibitor, blocked SI deficits associated with in vivo BLA-NAc stimulation. Additionally, optogenetic inhibition of the BLA-NAc circuit markedly increased SI in the Shank3B-/- mouse, an ASD model with substantial SI impairment, without affecting SI in WT mice. Finally, we demonstrated that JZL184 delivered systemically or directly to the NAc also normalized SI deficits in Shank3B-/- mice, while ex vivo JZL184 application corrected aberrant NAc excitatory and inhibitory neurotransmission and reduced BLA-NAc-elicited feed-forward inhibition of NAc neurons in Shank3B-/- mice. These data reveal circuit-level and neuromodulatory mechanisms regulating social function relevant to ASDs and suggest 2-AG augmentation could reduce social deficits via modulation of excitatory and inhibitory neurotransmission in the NAc.
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Affiliation(s)
- Oakleigh M Folkes
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Pharmacology and
| | - Rita Báldi
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Veronika Kondev
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - David J Marcus
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Nolan D Hartley
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Brandon D Turner
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jade K Ayers
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jordan J Baechle
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Maya P Misra
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Megan Altemus
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Carrie A Grueter
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Brad A Grueter
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sachin Patel
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Pharmacology and.,Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.,Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Garbett KA, Ding T, Allison J, Grueter CA, Grueter BA, Osteen KG, Strifert K, Sweatt JD. Synthetic female gonadal hormones alter neurodevelopmental programming and behavior in F 1 offspring. Horm Behav 2020; 126:104848. [PMID: 32918873 DOI: 10.1016/j.yhbeh.2020.104848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 05/04/2020] [Revised: 08/17/2020] [Accepted: 08/29/2020] [Indexed: 12/25/2022]
Abstract
The increased prevalence of neurodevelopmental disorders during the last half-century led us to investigate the potential for intergenerational detrimental neurodevelopmental effects of synthetic female gonadal hormones, typically used in contraceptive pills. We examined 3 separate cohorts of mice over the span of 2 years, a total of 150 female F0 mice and over 300 male and female rodents from their F1 progeny. We demonstrate that F1 male offsprings of female mice previously exposed to the synthetic estrogen 17α-ethinylestradiol (EE2) in combination with the synthetic progestin Norethindrone, exhibit neurodevelopmental and behavioral differences compared to control mice. Because the EE2 + Norethindrone administration resulted in gene expression changes in the exposed F0 mice ovaries persisting after the end of treatment, it is likely that the synthetic hormone treatment caused changes in the germline cells and that led to altered neurodevelopment in the offsprings. An altered gene expression pattern was discovered in the frontal cortex of male mice from the first offspring (F1.1) at infancy and an ADHD-like hyperactive locomotor behavior was exhibited in young male mice from the second offspring (F1.2) of female mice treated with contraceptive pill doses of EE2 + Norethindrone prior to pregnancy. The intergenerational neurodevelopmental effects of EE2 + Norethindrone treatment were sex specific, predominantly affecting males. Our observations in mice support the hypothesis that the use of synthetic contraceptive hormones is a potential environmental factor impacting the prevalence of human neurodevelopmental disorders. Additionally, our results indicate that contraceptive hormone drug safety assessments may need to be extended to F1 offspring.
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Affiliation(s)
- Krassimira A Garbett
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States of America.
| | - Tianbing Ding
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN 37232, United States of America
| | - John Allison
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States of America; Mouse Neurobehavioral Core, Vanderbilt University Medical Center, Nashville, TN 37232, United States of America
| | - Carrie A Grueter
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, United States of America
| | - Brad A Grueter
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN 37232, United States of America
| | - Kevin G Osteen
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN 37232, United States of America; VA Tennessee Valley Healthcare System, Nashville, TN 37232, United States of America
| | - Kim Strifert
- 2028 Sunset Hills Terrace, Nashville, TN 37215, United States of America
| | - J David Sweatt
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States of America.
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Abstract
Synaptic plasticity contributes to behavioral adaptations. As a key node in the reward pathway, the nucleus accumbens (NAc) is important for determining motivation-to-action outcomes. Across animal models of motivation including addiction, depression, anxiety, and hedonic feeding, selective recruitment of neuromodulatory signals and plasticity mechanisms have been a focus of physiologists and behaviorists alike. Experience-dependent plasticity mechanisms within the NAc vary depending on the distinct afferents and cell-types over time. A greater understanding of molecular mechanisms determining how these changes in synaptic strength track with behavioral adaptations will provide insight into the process of learning and memory along with identifying maladaptations underlying pathological behavior. Here, we summarize recent findings detailing how changes in NAc synaptic strength and mechanisms of plasticity manifest in various models of motivational disorders.
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Affiliation(s)
- Brandon D. Turner
- Vanderbilt Brain Institute, Nashville, Tennessee 37232, United States
| | - Daniel T. Kashima
- Vanderbilt Brain Institute, Nashville, Tennessee 37232, United States
- Medical Scientist Training Program, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Kevin M. Manz
- Vanderbilt Brain Institute, Nashville, Tennessee 37232, United States
- Medical Scientist Training Program, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Carrie A. Grueter
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Brad A. Grueter
- Vanderbilt Brain Institute, Nashville, Tennessee 37232, United States
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
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Chitraju C, Mejhert N, Haas JT, Diaz-Ramirez LG, Grueter CA, Imbriglio JE, Pinto S, Koliwad SK, Walther TC, Farese RV. Triglyceride Synthesis by DGAT1 Protects Adipocytes from Lipid-Induced ER Stress during Lipolysis. Cell Metab 2017; 26:407-418.e3. [PMID: 28768178 PMCID: PMC6195226 DOI: 10.1016/j.cmet.2017.07.012] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 04/10/2017] [Accepted: 07/17/2017] [Indexed: 12/29/2022]
Abstract
Triglyceride (TG) storage in adipose tissue provides the major reservoir for metabolic energy in mammals. During lipolysis, fatty acids (FAs) are hydrolyzed from adipocyte TG stores and transported to other tissues for fuel. For unclear reasons, a large portion of hydrolyzed FAs in adipocytes is re-esterified to TGs in a "futile," ATP-consuming, energy dissipating cycle. Here we show that FA re-esterification during adipocyte lipolysis is mediated by DGAT1, an ER-localized DGAT enzyme. Surprisingly, this re-esterification cycle does not preserve TG mass but instead functions to protect the ER from lipotoxic stress and related consequences, such as adipose tissue inflammation. Our data reveal an important role for DGAT activity and TG synthesis generally in averting ER stress and lipotoxicity, with specifically DGAT1 performing this function during stimulated lipolysis in adipocytes.
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Affiliation(s)
- Chandramohan Chitraju
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Niklas Mejhert
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Joel T Haas
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
| | | | - Carrie A Grueter
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
| | | | | | - Suneil K Koliwad
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA; Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Tobias C Walther
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
| | - Robert V Farese
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
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9
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Williams AS, Trefts E, Lantier L, Grueter CA, Bracy DP, James FD, Pozzi A, Zent R, Wasserman DH. Integrin-Linked Kinase Is Necessary for the Development of Diet-Induced Hepatic Insulin Resistance. Diabetes 2017; 66:325-334. [PMID: 27899483 PMCID: PMC5248997 DOI: 10.2337/db16-0484] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 11/17/2016] [Indexed: 12/17/2022]
Abstract
The liver extracellular matrix (ECM) expands with high-fat (HF) feeding. This finding led us to address whether receptors for the ECM, integrins, are key to the development of diet-induced hepatic insulin resistance. Integrin-linked kinase (ILK) is a downstream integrin signaling molecule involved in multiple hepatic processes, including those related to differentiation, wound healing, and metabolism. We tested the hypothesis that deletion of ILK in mice on an HF diet would disrupt the ECM-integrin signaling axis, thereby preventing the transformation into the insulin-resistant liver. To determine the role of ILK in hepatic insulin action in vivo, male C57BL/6J ILKlox/lox mice were crossed with Albcre mice to produce a hepatocyte-specific ILK deletion (ILKlox/loxAlbcre). Results from this study show that hepatic ILK deletion has no effect on insulin action in lean mice but sensitizes the liver to insulin during the challenge of HF feeding. This effect corresponds to changes in the expression and activation of key insulin signaling pathways as well as a greater capacity for hepatic mitochondrial glucose oxidation. This demonstrates that ILK contributes to hepatic insulin resistance and highlights the previously undefined role of integrin signaling in the pathogenesis of diet-induced hepatic insulin resistance.
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Affiliation(s)
- Ashley S Williams
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Elijah Trefts
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Louise Lantier
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Mouse Metabolic Phenotyping Center, Vanderbilt University, Nashville, TN
| | - Carrie A Grueter
- Department of Anesthesiology, Vanderbilt University, Nashville, TN
| | - Deanna P Bracy
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Freyja D James
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Ambra Pozzi
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Division of Nephrology, Department of Medicine, Vanderbilt University, Nashville, TN
- Department of Medicine, Veteran Affairs, Nashville, TN
| | - Roy Zent
- Division of Nephrology, Department of Medicine, Vanderbilt University, Nashville, TN
- Department of Medicine, Veteran Affairs, Nashville, TN
| | - David H Wasserman
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Mouse Metabolic Phenotyping Center, Vanderbilt University, Nashville, TN
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Joffe ME, Grueter CA, Grueter BA. Biological substrates of addiction. Wiley Interdiscip Rev Cogn Sci 2014; 5:151-171. [PMID: 24999377 PMCID: PMC4078878 DOI: 10.1002/wcs.1273] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 10/01/2013] [Accepted: 11/25/2013] [Indexed: 12/16/2022]
Abstract
This review is an introduction to addiction, the reward circuitry, and laboratory addiction models. Addiction is a chronic disease hallmarked by a state of compulsive drug seeking that persists despite negative consequences. Most of the advances in addiction research have centered on the canonical and contemporary drugs of abuse; however, addictions to other activities and stimuli also exist. Substances of abuse have the potential to induce long-lasting changes in the brain at the behavioral, circuit, and synaptic levels. Addiction-related behavioral changes involve initiation, escalation, and obsession to drug seeking and much of the current research is focused on mapping these manifestations to specific neural pathways. Drug abuse is well known to recruit components of the mesolimbic dopamine system, including the nucleus accumbens and ventral tegmental area. In addition, altered function of a wide variety of brain regions is tightly associated with specific manifestations of drug abuse. These regions peripheral to the mesolimbic pathway likely play a role in specific observed comorbidities and endophenotypes that can facilitate, or be caused by, substance abuse. Alterations in synaptic structure, function, and connectivity, as well as epigenetic and genetic mechanisms are thought to underlie the pathologies of addiction. In preclinical models, these persistent changes are studied at the levels of molecular pharmacology and biochemistry, ex vivo and in vivo electrophysiology, radiography, and behavior. Coordinating research efforts across these disciplines and examining cell type- and circuit-specific phenomena are crucial components for translating preclinical findings to viable medical interventions that effectively treat addiction and related disorders. WIREs Cogn Sci 2014, 5:151-171. doi: 10.1002/wcs.1273 Conflict of interest: The authors have declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Max E. Joffe
- Department of Pharmacology, Vanderbilt University School of Medicine
| | - Carrie A. Grueter
- Department of Anesthesiology, Vanderbilt University School of Medicine
| | - Brad A. Grueter
- Department of Anesthesiology, Vanderbilt Brain Institute, Vanderbilt University School of Medicine
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Shimazu T, Hirschey MD, Newman J, He W, Shirakawa K, Le Moan N, Grueter CA, Lim H, Saunders LR, Stevens RD, Newgard CB, Farese RV, de Cabo R, Ulrich S, Akassoglou K, Verdin E. Suppression of oxidative stress by β-hydroxybutyrate, an endogenous histone deacetylase inhibitor. Science 2012; 339:211-4. [PMID: 23223453 DOI: 10.1126/science.1227166] [Citation(s) in RCA: 1117] [Impact Index Per Article: 93.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Concentrations of acetyl-coenzyme A and nicotinamide adenine dinucleotide (NAD(+)) affect histone acetylation and thereby couple cellular metabolic status and transcriptional regulation. We report that the ketone body d-β-hydroxybutyrate (βOHB) is an endogenous and specific inhibitor of class I histone deacetylases (HDACs). Administration of exogenous βOHB, or fasting or calorie restriction, two conditions associated with increased βOHB abundance, all increased global histone acetylation in mouse tissues. Inhibition of HDAC by βOHB was correlated with global changes in transcription, including that of the genes encoding oxidative stress resistance factors FOXO3A and MT2. Treatment of cells with βOHB increased histone acetylation at the Foxo3a and Mt2 promoters, and both genes were activated by selective depletion of HDAC1 and HDAC2. Consistent with increased FOXO3A and MT2 activity, treatment of mice with βOHB conferred substantial protection against oxidative stress.
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Affiliation(s)
- Tadahiro Shimazu
- Gladstone Institute of Virology and Immunology, San Francisco, CA 94158, USA
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12
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Haas JT, Winter HS, Lim E, Kirby A, Blumenstiel B, DeFelice M, Gabriel S, Jalas C, Branski D, Grueter CA, Toporovski MS, Walther TC, Daly MJ, Farese RV. DGAT1 mutation is linked to a congenital diarrheal disorder. J Clin Invest 2012; 122:4680-4. [PMID: 23114594 DOI: 10.1172/jci64873] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 09/06/2012] [Indexed: 01/06/2023] Open
Abstract
Congenital diarrheal disorders (CDDs) are a collection of rare, heterogeneous enteropathies with early onset and often severe outcomes. Here, we report a family of Ashkenazi Jewish descent, with 2 out of 3 children affected by CDD. Both affected children presented 3 days after birth with severe, intractable diarrhea. One child died from complications at age 17 months. The second child showed marked improvement, with resolution of most symptoms at 10 to 12 months of age. Using exome sequencing, we identified a rare splice site mutation in the DGAT1 gene and found that both affected children were homozygous carriers. Molecular analysis of the mutant allele indicated a total loss of function, with no detectable DGAT1 protein or activity produced. The precise cause of diarrhea is unknown, but we speculate that it relates to abnormal fat absorption and buildup of DGAT substrates in the intestinal mucosa. Our results identify DGAT1 loss-of-function mutations as a rare cause of CDDs. These findings prompt concern for DGAT1 inhibition in humans, which is being assessed for treating metabolic and other diseases.
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Affiliation(s)
- Joel T Haas
- Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, USA
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Streeper RS, Grueter CA, Salomonis N, Cases S, Levin MC, Koliwad SK, Zhou P, Hirschey MD, Verdin E, Farese RV. Deficiency of the lipid synthesis enzyme, DGAT1, extends longevity in mice. Aging (Albany NY) 2012; 4:13-27. [PMID: 22291164 PMCID: PMC3292902 DOI: 10.18632/aging.100424] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Accepted: 01/28/2012] [Indexed: 12/17/2022]
Abstract
Calorie restriction results in leanness, which is linked to metabolic conditions that favor longevity. We show here that deficiency of the triglyceride synthesis enzyme acyl CoA:diacylglycerol acyltransferase 1 (DGAT1), which promotes leanness, also extends longevity without limiting food intake. Female DGAT1-deficient mice were protected from age-related increases in body fat, tissue triglycerides, and inflammation in white adipose tissue. This protection was accompanied by increased mean and maximal life spans of ~25% and ~10%, respectively. Middle-agedDgat1-/- mice exhibited several features associated with longevity, including decreased levels of circulating insulin growth factor 1 (IGF1) and reduced fecundity. Thus, deletion of DGAT1 in mice provides a model of leanness and extended lifespan that is independent of calorie restriction.
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Affiliation(s)
- Ryan S. Streeper
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
- Cardiovascular Research Institute, San Francisco, California, USA
| | - Carrie A. Grueter
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
| | - Nathan Salomonis
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
| | - Sylvaine Cases
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
| | - Malin C. Levin
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
| | - Suneil K. Koliwad
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
- Cardiovascular Research Institute, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, California, USA
| | - Ping Zhou
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
| | - Matthew D. Hirschey
- Gladstone Institute of Virology and Immunology, San Francisco, California, USA
| | - Eric Verdin
- Gladstone Institute of Virology and Immunology, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, California, USA
| | - Robert V. Farese
- Gladstone Institute of Cardiovascular Disease, San Francisco, California, USA
- Cardiovascular Research Institute, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, California, USA
- Departments of Biochemistry and Biophysics, University of California, San Francisco, California, USA
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Hirschey MD, Shimazu T, Jing E, Grueter CA, Collins AM, Aouizerat B, Stančáková A, Goetzman E, Lam MM, Schwer B, Stevens RD, Muehlbauer MJ, Kakar S, Bass NM, Kuusisto J, Laakso M, Alt FW, Newgard CB, Farese RV, Kahn CR, Verdin E. SIRT3 deficiency and mitochondrial protein hyperacetylation accelerate the development of the metabolic syndrome. Mol Cell 2011; 44:177-90. [PMID: 21856199 DOI: 10.1016/j.molcel.2011.07.019] [Citation(s) in RCA: 604] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 07/06/2011] [Accepted: 07/15/2011] [Indexed: 12/16/2022]
Abstract
Acetylation is increasingly recognized as an important metabolic regulatory posttranslational protein modification, yet the metabolic consequence of mitochondrial protein hyperacetylation is unknown. We find that high-fat diet (HFD) feeding induces hepatic mitochondrial protein hyperacetylation in mice and downregulation of the major mitochondrial protein deacetylase SIRT3. Mice lacking SIRT3 (SIRT3KO) placed on a HFD show accelerated obesity, insulin resistance, hyperlipidemia, and steatohepatitis compared to wild-type (WT) mice. The lipogenic enzyme stearoyl-CoA desaturase 1 is highly induced in SIRT3KO mice, and its deletion rescues both WT and SIRT3KO mice from HFD-induced hepatic steatosis and insulin resistance. We further identify a single nucleotide polymorphism in the human SIRT3 gene that is suggestive of a genetic association with the metabolic syndrome. This polymorphism encodes a point mutation in the SIRT3 protein, which reduces its overall enzymatic efficiency. Our findings show that loss of SIRT3 and dysregulation of mitochondrial protein acetylation contribute to the metabolic syndrome.
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Affiliation(s)
- Matthew D Hirschey
- Gladstone Institute of Virology and Immunology, San Francisco, CA 94158, USA
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Abstract
OBJECTIVE Insulin represses the expression of gluconeogenic genes at the mRNA level, but the hormone appears to have only weak inhibitory effects in vivo. The aims of this study were 1) to determine the maximal physiologic effect of insulin, 2) to determine the relative importance of its effects on gluconeogenic regulatory sites, and 3) to correlate those changes with alterations at the cellular level. RESEARCH DESIGN AND METHODS Conscious 60-h fasted canines were studied at three insulin levels (near basal, 4x, or 16x) during a 5-h euglycemic clamp. Pancreatic hormones were controlled using somatostatin with portal insulin and glucagon infusions. Glucose metabolism was assessed using the arteriovenous difference technique, and molecular signals were assessed. RESULTS Insulin reduced gluconeogenic flux to glucose-6-phosphate (G6P) but only at the near-maximal physiological level (16x basal). The effect was modest compared with its inhibitory effect on net hepatic glycogenolysis, occurred within 30 min, and was associated with a marked decrease in hepatic fat oxidation, increased liver fructose 2,6-bisphosphate level, and reductions in lactate, glycerol, and amino acid extraction. No further diminution in gluconeogenic flux to G6P occurred over the remaining 4.5 h of the study, despite a marked decrease in PEPCK content, suggesting poor control strength for this enzyme in gluconeogenic regulation in canines. CONCLUSIONS Gluconeogenic flux can be rapidly inhibited by high insulin levels in canines. Initially decreased hepatic lactate extraction is important, and later reduced gluconeogenic precursor availability plays a role. Changes in PEPCK appear to have little or no acute effect on gluconeogenic flux.
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Affiliation(s)
- Dale S Edgerton
- Vanderbilt University Medical Center, Nashville, Tennessee, USA.
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