ABSTRACT
BACKGROUND: This study aimed to analyze genotype-phenotype correlations in children with Gitelman syndrome (GS). METHODS: This multicenter retrospective study included 50 Korean children diagnosed with SLC12A3 variants in one or both alleles and the typical laboratory findings of GS. Genetic testing was performed using the Sanger sequencing except for one patient. RESULTS: The median age at the diagnosis was 10.5 years (interquartile range, 6.8;14.1), and 41 patients were followed up for a median duration of 5.4 years (interquartile range, 4.1;9.6). A total of 30 different SLC12A3 variants were identified. Of the patients, 34 (68%) had biallelic variants, and 16 (32%) had monoallelic variants on examination. Among the patients with biallelic variants, those (n = 12) with the truncating variants in one or both alleles had lower serum chloride levels (92.2 ± 3.2 vs. 96.5 ± 3.8 mMol/L, P = 0.002) at onset, as well as lower serum potassium levels (3.0 ± 0.4 vs. 3.4 ± 0.3 mMol/L, P = 0.016), and lower serum chloride levels (96.1 ± 1.9 vs. 98.3 ± 3.0 mMol/L, P = 0.049) during follow-up than those without truncating variants (n = 22). Patients with monoallelic variants on examination showed similar phenotypes and treatment responsiveness to those with biallelic variants. CONCLUSIONS: Patients with GS who had truncating variants in one or both alleles had more severe electrolyte abnormalities than those without truncating variants. Patients with GS who had monoallelic SLC12A3 variants on examination had almost the same phenotypes, response to treatment, and long-term prognosis as those with biallelic variants.
Subject(s)
Genetic Association Studies , Gitelman Syndrome , Solute Carrier Family 12, Member 3 , Humans , Gitelman Syndrome/genetics , Gitelman Syndrome/diagnosis , Solute Carrier Family 12, Member 3/genetics , Child , Male , Retrospective Studies , Female , Adolescent , Phenotype , Republic of Korea , Child, Preschool , Mutation , Potassium/blood , Genetic Predisposition to Disease , Chlorides/bloodABSTRACT
We studied the brain mechanisms underlying action selection in a social dilemma setting in which individuals' effortful gains are unfairly distributed among group members. A stable "worker-parasite" relationship developed when three individually operant-conditioned rats were placed together in a Skinner box equipped with response lever and food dispenser on opposite sides. Specifically, one rat, the "worker," engaged in lever-pressing while the other two "parasitic" rats profited from the worker's effort by crowding the feeder in anticipation of food. Anatomically, c-Fos expression in the anterior cingulate cortex (ACC) was significantly higher in worker rats than in parasite rats. Functionally, ACC inactivation suppressed the worker's lever-press behavior drastically under social, but only mildly under individual, settings. Transcriptionally, GABAA receptor- and potassium channel-related messenger RNA expressions were reliably lower in the worker's, relative to parasite's, ACC. These findings indicate the requirement of ACC activation for the expression of exploitable, effortful behavior, which could be mediated by molecular pathways involving GABAA receptor/potassium channel proteins.
Subject(s)
Choice Behavior/physiology , Conditioning, Operant/physiology , Gyrus Cinguli/pathology , Amygdala/metabolism , Animals , Behavior, Animal , Decision Making/physiology , Male , Potassium Channels/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Rats , Rats, Sprague-Dawley , Reward , Social BehaviorABSTRACT
The genetic spectrum of genetic kidney diseases (GKD) and the application of genetic diagnoses to patient care were assessed by whole exome sequencing (WES) of the DNA of 172 pediatric or adult patients with various kidney diseases. WES diagnosed genetic diseases in 63 (36.6%) patients. The diagnostic yields in patients with glomerulopathy were 33.8% (25/74 pts) due to variants in 10 genes, 58.8% (20/34) in patients with tubulointerstitial disease due to variants in 18 genes, 33.3% (15/45) in patients with cystic disease/ciliopathy due to variants in 10 genes, 18.2% (2/11) in patients with congenital anomalies of the kidneys and urinary tract (CAKUT) due to variants in two genes, and 12.5% (1/8) in patients with end stage kidney disease (ESKD). The diagnosis rate was high in patients aged <1-6 years (46-50.0%), and low in patients aged ≥40 years (9.1%). Renal phenotype was reclassified in 10 (15.9%) of 63 patients and clinical management altered in 10 (15.9%) of 63 patients after genetic diagnosis. In conclusion, these findings demonstrated the diagnostic utility of WES and its effective clinical application in patients, with various kinds of kidney diseases, across the different age groups.
Subject(s)
Nephritis, Interstitial , Urinary Tract , Humans , Exome Sequencing , Kidney/abnormalities , PhenotypeABSTRACT
ß-catenin is a multi-functional protein that has an important role in the mature central nervous system; its dysfunction has been implicated in several neuropsychiatric disorders, including depression. Here we show that in mice ß-catenin mediates pro-resilient and anxiolytic effects in the nucleus accumbens, a key brain reward region, an effect mediated by D2-type medium spiny neurons. Using genome-wide ß-catenin enrichment mapping, we identify Dicer1-important in small RNA (for example, microRNA) biogenesis--as a ß-catenin target gene that mediates resilience. Small RNA profiling after excising ß-catenin from nucleus accumbens in the context of chronic stress reveals ß-catenin-dependent microRNA regulation associated with resilience. Together, these findings establish ß-catenin as a critical regulator in the development of behavioural resilience, activating a network that includes Dicer1 and downstream microRNAs. We thus present a foundation for the development of novel therapeutic targets to promote stress resilience.
Subject(s)
DEAD-box RNA Helicases/genetics , Gene Expression Regulation , MicroRNAs/genetics , Resilience, Psychological , Ribonuclease III/genetics , Stress, Physiological/genetics , beta Catenin/metabolism , Adaptation, Physiological/genetics , Animals , DEAD-box RNA Helicases/metabolism , Depression/physiopathology , Gene Expression Profiling , Genome-Wide Association Study , Humans , Male , Mice , Mice, Inbred C57BL , MicroRNAs/metabolism , Neurons/metabolism , Ribonuclease III/metabolism , Signal Transduction , beta Catenin/geneticsABSTRACT
AIM: Although the incidence of urinary tract infection (UTI) in children with lower respiratory tract infection (LRTI) has been reported as 3.1-10.0%, the exact concomitant prevalence is questionable. Here, we evaluated the prevalence and related risk factors of UTI associated with LRTI in children under 36 months of age. METHODS: We retrospectively reviewed the medical charts of 1574 patients under 36 months of age who were hospitalised with LRTI from January 2017 to December 2019 in a single centre, Seoul, South Korea. Among them, we analysed 278 patients who showed fever and performed urine evaluation. Urine was collected by catheterisation in children under 24 months of age and by voided urine between 24 and 36 months of age. RESULTS: The prevalence of concomitant UTI and LRTI was 13.6% in children under 24 months of age. Mean age was significantly younger in the UTI versus non-UTI group (6.93 ± 7.26 months vs. 12.61 ± 11.70 months; P < 0.001). When the participants were stratified by age, the prevalence of UTI was significantly higher in children younger than 24 months of age compared to older ones (P = 0.006). UTIs were more prevalent in boys than in girls (14.6% vs. 5.8%, P = 0.018). Peak body temperature, fever duration, premature birth and detected respiratory virus type did not differ between groups. CONCLUSIONS: It is not uncommon for children with LRTI with fever to be accompanied by UTI. When evaluating for UTI in children with febrile LRTI, age and sex must be considered.
Subject(s)
Respiratory Tract Infections , Urinary Tract Infections , Child , Child, Preschool , Female , Fever/epidemiology , Fever/etiology , Humans , Infant , Male , Republic of Korea/epidemiology , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Retrospective Studies , Urinary Tract Infections/diagnosis , Urinary Tract Infections/epidemiologyABSTRACT
Ventral tegmental area (VTA) dopamine neurons in the brain's reward circuit have a crucial role in mediating stress responses, including determining susceptibility versus resilience to social-stress-induced behavioural abnormalities. VTA dopamine neurons show two in vivo patterns of firing: low frequency tonic firing and high frequency phasic firing. Phasic firing of the neurons, which is well known to encode reward signals, is upregulated by repeated social-defeat stress, a highly validated mouse model of depression. Surprisingly, this pathophysiological effect is seen in susceptible mice only, with no apparent change in firing rate in resilient individuals. However, direct evidence--in real time--linking dopamine neuron phasic firing in promoting the susceptible (depression-like) phenotype is lacking. Here we took advantage of the temporal precision and cell-type and projection-pathway specificity of optogenetics to show that enhanced phasic firing of these neurons mediates susceptibility to social-defeat stress in freely behaving mice. We show that optogenetic induction of phasic, but not tonic, firing in VTA dopamine neurons of mice undergoing a subthreshold social-defeat paradigm rapidly induced a susceptible phenotype as measured by social avoidance and decreased sucrose preference. Optogenetic phasic stimulation of these neurons also quickly induced a susceptible phenotype in previously resilient mice that had been subjected to repeated social-defeat stress. Furthermore, we show differences in projection-pathway specificity in promoting stress susceptibility: phasic activation of VTA neurons projecting to the nucleus accumbens (NAc), but not to the medial prefrontal cortex (mPFC), induced susceptibility to social-defeat stress. Conversely, optogenetic inhibition of the VTA-NAc projection induced resilience, whereas inhibition of the VTA-mPFC projection promoted susceptibility. Overall, these studies reveal novel firing-pattern- and neural-circuit-specific mechanisms of depression.
Subject(s)
Depression/physiopathology , Dopaminergic Neurons/metabolism , Mesencephalon/cytology , Social Behavior , Stress, Psychological/physiopathology , Animals , Depression/etiology , Food Preferences , Male , Mice , Neural Pathways , Nucleus Accumbens/physiology , Optogenetics , Phenotype , Prefrontal Cortex/physiology , Stress, Psychological/complications , Sucrose/administration & dosage , Time Factors , Ventral Tegmental Area/physiologyABSTRACT
ATP-dependent chromatin remodeling proteins are being implicated increasingly in the regulation of complex behaviors, including models of several psychiatric disorders. Here, we demonstrate that Baz1b, an accessory subunit of the ISWI family of chromatin remodeling complexes, is upregulated in the nucleus accumbens (NAc), a key brain reward region, in both chronic cocaine-treated mice and mice that are resilient to chronic social defeat stress. In contrast, no regulation is seen in mice that are susceptible to this chronic stress. Viral-mediated overexpression of Baz1b, along with its associated subunit Smarca5, in mouse NAc is sufficient to potentiate both rewarding responses to cocaine, including cocaine self-administration, and resilience to chronic social defeat stress. However, despite these similar, proreward behavioral effects, genome-wide mapping of BAZ1B in NAc revealed mostly distinct subsets of genes regulated by these chromatin remodeling proteins after chronic exposure to either cocaine or social stress. Together, these findings suggest important roles for BAZ1B and its associated chromatin remodeling complexes in NAc in the regulation of reward behaviors to distinct emotional stimuli and highlight the stimulus-specific nature of the actions of these regulatory proteins. SIGNIFICANCE STATEMENT: We show that BAZ1B, a component of chromatin remodeling complexes, in the nucleus accumbens regulates reward-related behaviors in response to chronic exposure to both rewarding and aversive stimuli by regulating largely distinct subsets of genes.
Subject(s)
Behavior, Animal/physiology , Emotions/physiology , Nucleus Accumbens/physiology , Reward , Transcription Factors/genetics , Transcription Factors/physiology , Adenosine Triphosphatases/metabolism , Animals , Behavior, Animal/drug effects , Chromatin/genetics , Chromosomal Proteins, Non-Histone/metabolism , Cocaine/pharmacology , Epigenesis, Genetic/drug effects , Male , Mice , Mice, Inbred C57BL , Motor Activity/drug effects , Nucleus Accumbens/drug effects , Nucleus Accumbens/metabolism , Rats , Rats, Sprague-Dawley , Self Administration , Social Environment , Stress, PsychologicalABSTRACT
The objective of this study was to investigate national surgical trends for distal radius fractures (DRFs) in Korea and analyze healthcare institution type-specific surgical trends. We analyzed a nationwide database acquired from the Korean Health Insurance Review and Assessment Service (HIRA) from 2011 to 2015. International Classification of Diseases, 10th revision (ICD-10) codes and procedure codes were used to identify patients aged ≥ 20 years with newly diagnosed DRFs. A total of 459,388 DRFs occurred from 2011 to 2015. The proportion of DRF cases treated by surgery tended to increase over time, from 32.6% in 2011 to 38.3% in 2015 (P < 0.001). Open reduction with internal fixation (ORIF) using a plate steadily gained in popularity each year, increasing from 39.2% of overall surgeries in 2011 to 60.9% in 2015. The type of surgery for DRFs differed depending on the type of healthcare institution. ORIF (91%) was the most popular procedure in tertiary hospitals, whereas percutaneous pinning (58%) was most popular in clinics. In addition, general hospitals and hospitals with 30-100 beds used external fixation more frequently than tertiary hospitals and clinics did. Overall, our findings indicate that surgical treatment of DRF, particularly ORIF, continues to increase, and that the component ratio of operation codes differed according to the healthcare institution type.
Subject(s)
Bone Nails/statistics & numerical data , Bone Plates/statistics & numerical data , Fracture Fixation, Internal/methods , Radius Fractures/surgery , Adult , Female , Fracture Fixation, Internal/trends , Hospitals , Humans , Male , Middle Aged , Republic of Korea , Treatment Outcome , Young AdultABSTRACT
Depression and anxiety disorders are more prevalent in females, but the majority of research in animal models, the first step in finding new treatments, has focused predominantly on males. Here we report that exposure to subchronic variable stress (SCVS) induces depression-associated behaviors in female mice, whereas males are resilient as they do not develop these behavioral abnormalities. In concert with these different behavioral responses, transcriptional analysis of nucleus accumbens (NAc), a major brain reward region, by use of RNA sequencing (RNA-seq) revealed markedly different patterns of stress regulation of gene expression between the sexes. Among the genes displaying sex differences was DNA methyltransferase 3a (Dnmt3a), which shows a greater induction in females after SCVS. Interestingly, Dnmt3a expression levels were increased in the NAc of depressed humans, an effect seen in both males and females. Local overexpression of Dnmt3a in NAc rendered male mice more susceptible to SCVS, whereas Dnmt3a knock-out in this region rendered females more resilient, directly implicating this gene in stress responses. Associated with this enhanced resilience of female mice upon NAc knock-out of Dnmt3a was a partial shift of the NAc female transcriptome toward the male pattern after SCVS. These data indicate that males and females undergo different patterns of transcriptional regulation in response to stress and that a DNA methyltransferase in NAc contributes to sex differences in stress vulnerability. SIGNIFICANCE STATEMENT: Women have a higher incidence of depression than men. However, preclinical models, the first step in developing new diagnostics and therapeutics, have been performed mainly on male subjects. Using a stress-based animal model of depression that causes behavioral effects in females but not males, we demonstrate a sex-specific transcriptional profile in brain reward circuitry. This transcriptional profile can be altered by removal of an epigenetic mechanism, which normally suppresses DNA transcription, creating a hybrid male/female transcriptional pattern. Removal of this epigenetic mechanism also induces behavioral resilience to stress in females. These findings shed new light onto molecular factors controlling sex differences in stress response.
Subject(s)
Nucleus Accumbens/physiopathology , Resilience, Psychological , Stress, Psychological/genetics , Stress, Psychological/psychology , Transcriptome/genetics , Animals , Anxiety/genetics , Anxiety/psychology , Chronic Disease , DNA (Cytosine-5-)-Methyltransferases/biosynthesis , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA Methyltransferase 3A , Feeding Behavior , Female , Gene Expression Regulation, Enzymologic/genetics , Gene Knock-In Techniques , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Motor Activity , Repression, Psychology , Sex Characteristics , Swimming/psychologyABSTRACT
Sirtuins (SIRTs), class III histone deacetylases, are well characterized for their control of cellular physiology in peripheral tissues, but their influence in brain under normal and pathological conditions remains poorly understood. Here, we establish an essential role for SIRT1 and SIRT2 in regulating behavioral responses to cocaine and morphine through actions in the nucleus accumbens (NAc), a key brain reward region. We show that chronic cocaine administration increases SIRT1 and SIRT2 expression in the mouse NAc, while chronic morphine administration induces SIRT1 expression alone, with no regulation of all other sirtuin family members observed. Drug induction of SIRT1 and SIRT2 is mediated in part at the transcriptional level via the drug-induced transcription factor ΔFosB and is associated with robust histone modifications at the Sirt1 and Sirt2 genes. Viral-mediated overexpression of SIRT1 or SIRT2 in the NAc enhances the rewarding effects of both cocaine and morphine. In contrast, the local knockdown of SIRT1 from the NAc of floxed Sirt1 mice decreases drug reward. Such behavioral effects of SIRT1 occur in concert with its regulation of numerous synaptic proteins in NAc as well as with SIRT1-mediated induction of dendritic spines on NAc medium spiny neurons. These studies establish sirtuins as key mediators of the molecular and cellular plasticity induced by drugs of abuse in NAc, and of the associated behavioral adaptations, and point toward novel signaling pathways involved in drug action.
Subject(s)
Cocaine-Related Disorders/metabolism , Morphine Dependence/metabolism , Nucleus Accumbens/metabolism , Signal Transduction/physiology , Sirtuin 1/metabolism , Animals , Chromatin Immunoprecipitation , Cocaine/pharmacology , Dopamine Uptake Inhibitors/pharmacology , Immunoblotting , Male , Mice , Mice, Inbred C57BL , Morphine/pharmacology , Narcotics/pharmacology , Nucleus Accumbens/drug effects , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Reward , Signal Transduction/drug effects , Sirtuin 2/metabolismABSTRACT
The transcription factor, ΔFosB, is robustly and persistently induced in striatum by several chronic stimuli, such as drugs of abuse, antipsychotic drugs, natural rewards, and stress. However, very few studies have examined the degree of ΔFosB induction in the two striatal medium spiny neuron (MSN) subtypes. We make use of fluorescent reporter BAC transgenic mice to evaluate induction of ΔFosB in dopamine receptor 1 (D1) enriched and dopamine receptor 2 (D2) enriched MSNs in ventral striatum, nucleus accumbens (NAc) shell and core, and in dorsal striatum (dStr) after chronic exposure to several drugs of abuse including cocaine, ethanol, Δ(9)-tetrahydrocannabinol, and opiates; the antipsychotic drug, haloperidol; juvenile enrichment; sucrose drinking; calorie restriction; the serotonin selective reuptake inhibitor antidepressant, fluoxetine; and social defeat stress. Our findings demonstrate that chronic exposure to many stimuli induces ΔFosB in an MSN-subtype selective pattern across all three striatal regions. To explore the circuit-mediated induction of ΔFosB in striatum, we use optogenetics to enhance activity in limbic brain regions that send synaptic inputs to NAc; these regions include the ventral tegmental area and several glutamatergic afferent regions: medial prefrontal cortex, amygdala, and ventral hippocampus. These optogenetic conditions lead to highly distinct patterns of ΔFosB induction in MSN subtypes in NAc core and shell. Together, these findings establish selective patterns of ΔFosB induction in striatal MSN subtypes in response to chronic stimuli and provide novel insight into the circuit-level mechanisms of ΔFosB induction in striatum.
Subject(s)
Corpus Striatum/cytology , Dopamine Agents/pharmacology , Emotions/drug effects , Optogenetics , Proto-Oncogene Proteins c-fos/metabolism , Animals , Antidepressive Agents/pharmacology , Cannabinoid Receptor Agonists/pharmacology , Dronabinol/pharmacology , Environment , Gene Expression Regulation/drug effects , Green Fluorescent Proteins/genetics , In Vitro Techniques , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neurons/classification , Neurons/drug effects , Phosphopyruvate Hydratase/metabolism , Receptors, Dopamine D1/genetics , Receptors, Dopamine D2/geneticsABSTRACT
Stressful circumstances are significant contributors to mental illnesses such as major depressive disorder. Anhedonia, defined as loss of the ability to enjoy pleasure in pleasurable situations, including rewarding activities or social contexts, is considered a key symptom of depression. Although stress-induced depression is associated with anhedonia in humans and animals, the underlying molecular mechanisms of anhedonic responses remain poorly understood. In this study, we demonstrated that synaptotagmin-4 (SYT4), which is involved in the release of neurotransmitters and neurotrophic factors, is implicated in chronic stress-induced anhedonia. Employing chronic unpredictable stress (CUS), we evaluated two subpopulations of mice, susceptible (SUS, anhedonic) and resilient (RES, nonanhedonic), based on sucrose preference, which was strongly correlated with social reward. The FosTRAP (targeted recombination in active populations) system and optogenetic approach revealed that neural activity in the medial prefrontal cortex (mPFC) was significantly associated with CUS-induced anhedonic behavioral phenotypes. By conducting weighted gene coexpression network analysis of RNA sequencing data from the mPFC of SUS and RES mice, we identified Syt4 as a hub gene in a gene network that was unique to anhedonia. We also confirmed that Syt4 overexpression in the mPFC was pro-susceptible, while Syt4 knockdown was pro-resilient; the pro-susceptible effects of SYT4 were mediated through a reduction in brain-derived neurotrophic factor (BDNF)-tropomyosin receptor kinase B (TrkB) signaling in the mPFC. These findings suggest that SYT4-BDNF interactions in the mPFC represent a crucial regulatory mechanism of anhedonic susceptibility to chronic stress.
Subject(s)
Anhedonia , Brain-Derived Neurotrophic Factor , Depressive Disorder, Major , Animals , Humans , Mice , Brain-Derived Neurotrophic Factor/genetics , Cytoplasm , Prefrontal CortexABSTRACT
Background: Fear responses significantly affect daily life and shape our approach to uncertainty. However, the potential resurgence of fear in unfamiliar situations poses a significant challenge to exposure-based therapies for maladaptive fear responses. Nonetheless, how novel contextual stimuli are associated with the relapse of extinguished fear remains unknown. Methods: Using a context-dependent fear renewal model, the functional circuits and underlying mechanisms of the posterior parietal cortex (PPC) and anterior cingulate cortex (ACC) were investigated using optogenetic, histological, in vivo, and ex vivo electrophysiological and pharmacological techniques. Results: We demonstrated that the PPC-to-ACC pathway governs fear relapse in a novel context. We observed enhanced populational calcium activity in the ACC neurons that received projections from the PPC and increased synaptic activity in the basolateral amygdala-projecting PPC-to-ACC neurons upon renewal in a novel context, where excitatory postsynaptic currents amplitudes increased but inhibitory postsynaptic current amplitudes decreased. In addition, we found that parvalbumin-expressing interneurons controlled novel context-dependent fear renewal, which was blocked by the chronic administration of fluoxetine. Conclusions: Our findings highlight the PPC-to-ACC pathway in mediating the relapse of extinguished fear in novel contexts, thereby contributing significant insights into the intricate neural mechanisms that govern fear renewal.
To improve outcomes for exposure-based therapy, it is vital to understand the renewal of fear after extinction in new environments. Using optogenetics and other techniques, Joo et al. found that a brain circuit connecting the posterior parietal cortex (PPC) to the anterior cingulate cortex (ACC) is crucial for the return of fear memories in mice exposed to a novel context. Certain PPCâACC neuron types and their connections to the amygdala became more active during fear renewal in a novel context, and inhibiting parvalbumin-expressing interneurons reduced this fear response. This study provides insights into the brain mechanisms underlying the reappearance of fear in unfamiliar situations.
ABSTRACT
Social animals compete for limited resources, resulting in a social hierarchy. Although different neuronal subpopulations in the medial prefrontal cortex (mPFC), which has been mechanistically implicated in social dominance behavior, encode distinct social competition behaviors, their identities and associated molecular underpinnings have not yet been identified. In this study, we found that mPFC neurons projecting to the nucleus accumbens (mPFC-NAc) encode social winning behavior, whereas mPFC neurons projecting to the ventral tegmental area (mPFC-VTA) encode social losing behavior. High-throughput single-cell transcriptomic analysis and projection-specific genetic manipulation revealed that the expression level of POU domain, class 3, transcription factor 1 (Pou3f1) in mPFC-VTA neurons controls social hierarchy. Optogenetic activation of mPFC-VTA neurons increases Pou3f1 expression and lowers social rank. Together, these data demonstrate that discrete activity and gene expression in separate mPFC projections oppositely orchestrate social competition and hierarchy.
Subject(s)
Nucleus Accumbens , Ventral Tegmental Area , Animals , Ventral Tegmental Area/physiology , Nucleus Accumbens/physiology , Social Behavior , Prefrontal Cortex/physiology , NeuronsABSTRACT
ΔFosB, a Fosb gene product, is induced in nucleus accumbens (NAc) and caudate-putamen (CPu) by repeated exposure to drugs of abuse such as cocaine. This induction contributes to aberrant patterns of gene expression and behavioral abnormalities seen with repeated drug exposure. Here, we assessed whether a remote history of cocaine exposure in rats might alter inducibility of the Fosb gene elicited by subsequent drug exposure. We show that prior chronic cocaine administration, followed by extended withdrawal, increases inducibility of Fosb in NAc, as evidenced by greater acute induction of ΔFosB mRNA and faster accumulation of ΔFosB protein after repeated cocaine reexposure. No such primed Fosb induction was observed in CPu; in fact, subsequent acute induction of ΔFosB mRNA was suppressed in CPu. These abnormal patterns of Fosb expression are associated with chromatin modifications at the Fosb gene promoter. Prior chronic cocaine administration induces a long-lasting increase in RNA polymerase II (Pol II) binding at the Fosb promoter in NAc only, suggesting that Pol II "stalling" primes Fosb for induction in this region upon reexposure to cocaine. A cocaine challenge then triggers the release of Pol II from the gene promoter, allowing for more rapid Fosb transcription. A cocaine challenge also decreases repressive histone modifications at the Fosb promoter in NAc, but increases such repressive marks and decreases activating marks in CPu. These results provide new insight into the chromatin dynamics at the Fosb promoter and reveal a novel mechanism for primed Fosb induction in NAc upon reexposure to cocaine.
Subject(s)
Cocaine/pharmacology , Dopamine Uptake Inhibitors/pharmacology , Epigenesis, Genetic/drug effects , Nucleus Accumbens/drug effects , Proto-Oncogene Proteins c-fos/genetics , Animals , Cocaine/administration & dosage , Dopamine Uptake Inhibitors/administration & dosage , Gene Expression/drug effects , Male , Motor Activity/drug effects , Nucleus Accumbens/metabolism , Promoter Regions, Genetic/drug effects , Proto-Oncogene Proteins c-fos/metabolism , Rats , Rats, Sprague-DawleyABSTRACT
Proinflammatory cytokines, such as IL-1beta, have been implicated in the cellular and behavioral effects of stress and in mood disorders, although the downstream signaling pathways underlying these effects have not been determined. In the present study, we demonstrate a critical role for NF-kappaB signaling in the actions of IL-1beta and stress. Stress inhibition of neurogenesis in the adult hippocampus, which has been implicated in the prodepressive effects of stress, is blocked by administration of an inhibitor of NF-kappaB. Further analysis reveals that stress activates NF-kappaB signaling and decreases proliferation of neural stem-like cells but not early neural progenitor cells in the adult hippocampus. We also find that depressive-like behaviors caused by exposure to chronic stress are mediated by NF-kappaB signaling. Together, these data identify NF-kappaB signaling as a critical mediator of the antineurogenic and behavioral actions of stress and suggest previously undescribed therapeutical targets for depression.
Subject(s)
Depressive Disorder/physiopathology , NF-kappa B/metabolism , Neurogenesis/physiology , Signal Transduction/physiology , Animals , Cell Proliferation/drug effects , Cells, Cultured , Depressive Disorder/psychology , Female , Hippocampus/cytology , Hippocampus/metabolism , Interleukin-1beta/pharmacology , Male , Mice , Mice, Transgenic , NF-kappa B/antagonists & inhibitors , NF-kappa B/genetics , Neurons/cytology , Neurons/drug effects , Neurons/metabolism , Phenylenediamines/pharmacology , Rats , Rats, Sprague-Dawley , Restraint, Physical/psychology , Signal Transduction/drug effects , Stem Cells/cytology , Stem Cells/drug effects , Stem Cells/metabolism , Stress, Psychological/physiopathology , Thiophenes/pharmacologyABSTRACT
The monoamine hypothesis has significantly improved our understanding of mood disorders and their treatment by linking monoaminergic abnormalities to the pathophysiology of mood disorders. Even 50 years after the monoamine hypothesis was established, some patients do not respond to treatments for depression, including selective serotonin reuptake drugs. Accumulating evidence shows that patients with treatment-resistant depression (TRD) have severe abnormalities in the neuroplasticity and neurotrophic factor pathways, indicating that different treatment approaches may be necessary. Therefore, the glutamate hypothesis is gaining attention as a novel hypothesis that can overcome monoamine restrictions. Glutamate has been linked to structural and maladaptive morphological alterations in several brain areas associated with mood disorders. Recently, ketamine, an N-methyl-D-aspartate receptor (NMDAR) antagonist, has shown efficacy in TRD treatment and has received the U.S. Food and Drug Administration approval, revitalizing psychiatry research. However, the mechanism by which ketamine improves TRD remains unclear. In this review, we re-examined the glutamate hypothesis, bringing the glutamate system onboard to join the modulation of the monoamine systems, emphasizing the most prominent ketamine antidepressant mechanisms, such as NMDAR inhibition and NMDAR disinhibition in GABAergic interneurons. Furthermore, we discuss the animal models used in preclinical studies and the sex differences in the effects of ketamine.
ABSTRACT
Mental health is influenced by the gut-brain axis; for example, gut dysbiosis has been observed in patients with major depressive disorder (MDD). Gut microbial changes by fecal microbiota transplantation or probiotics treatment reportedly modulates depressive symptoms. However, it remains unclear how gut dysbiosis contributes to mental dysfunction, and how correction of the gut microbiota alleviates neuropsychiatric disorders. Our previous study showed that chronic consumption of Lactobacillus reuteri ATG-F4 (F4) induced neurometabolic alterations in healthy mice. Here, we investigated whether F4 exerted therapeutic effects on depressive-like behavior by influencing the central nervous system. Using chronic unpredictable stress (CUS) to induce anhedonia, a key symptom of MDD, we found that chronic F4 consumption alleviated CUS-induced anhedonic behaviors, accompanied by biochemical changes in the gut, serum, and brain. Serum and brain metabolite concentrations involved in tryptophan metabolism were regulated by CUS and F4. F4 consumption reduced the elevated levels of serotonin (5-HT) in the brain observed in the CUS group. Additionally, the increased expression of Htr1a, a subtype of the 5-HT receptor, in the medial prefrontal cortex (mPFC) of stressed mice was restored to levels observed in stress-naïve mice following F4 supplementation. We further demonstrated the role of Htr1a using AAV-shRNA to downregulate Htr1a in the mPFC of CUS mice, effectively reversing CUS-induced anhedonic behavior. Together, our findings suggest F4 as a potential therapeutic approach for relieving some depressive symptoms and highlight the involvement of the tryptophan metabolism in mitigating CUS-induced depressive-like behaviors through the action of this bacterium.
ABSTRACT
BACKGROUND: Familial renal glucosuria (FRG) is an inherited renal tubular disorder characterized by persistent isolated glucosuria in the absence of hyperglycemia that is caused by mutations in the sodium-glucose cotransporter SGLT2 coding gene, SLC5A2. OBJECTIVE: We conducted molecular and phenotype analyses of a cohort of 23 unrelated Korean children with FRG. METHODS: Mutational analysis of the SLC5A2 gene was conducted in this multicenter study organized by the Korean Society of Pediatric Nephrology. RESULTS: A total of 21 different SLC5A2 mutations were detected, including 19 novel mutations. All patients had at least one mutated allele; ten patients had homozygous or compound heterozygous mutations and 13 patients had a single heterozygous mutation. Most mutations were private. Patients with two mutations were diagnosed earlier with larger amounts of urinary glucose excretion than patients with single mutations. Pedigree analysis data were consistent with the inheritance of a codominant trait with incomplete penetrance. CONCLUSIONS: These findings extend the allelic heterogeneity in FRG and confirm previous observations of inheritance and genotypephenotype correlation in patients with this disease.
Subject(s)
Genetic Predisposition to Disease , Glycosuria, Renal/genetics , Sodium-Glucose Transporter 2/genetics , Adolescent , Child , Child, Preschool , DNA Mutational Analysis , Female , Genetic Association Studies , Genotype , Glycosuria, Renal/metabolism , Humans , Infant , Korea , Male , Mutation , Pedigree , PhenotypeABSTRACT
BACKGROUND: Metabotropic glutamate receptor 5 (mGluR5) has been implicated in stress-related psychiatric disorders, particularly major depressive disorder. Although growing evidence supports the proresilient role of mGluR5 in corticolimbic circuitry in the depressive-like behaviors following chronic stress exposure, the underlying neural mechanisms, including circuits and molecules, remain unknown. METHODS: We measured the c-Fos expression and probability of neurotransmitter release in and from basolateral amygdala (BLA) neurons projecting to the medial prefrontal cortex (mPFC) and to the ventral hippocampus (vHPC) after chronic social defeat stress. The role of BLA projections in depressive-like behaviors was assessed using optogenetic manipulations, and the underlying molecular mechanisms of mGluR5 and downstream signaling were investigated by Western blotting, viral-mediated gene transfer, and pharmacological manipulations. RESULTS: Chronic social defeat stress disrupted neural activity and glutamatergic transmission in both BLA projections. Optogenetic activation of BLA projections reversed the detrimental effects of chronic social defeat stress on depressive-like behaviors and mGluR5 expression in the mPFC and vHPC. Conversely, inhibition of BLA projections of mice undergoing subthreshold social defeat stress induced a susceptible phenotype and mGluR5 reduction. These two BLA circuits appeared to act in an independent way. We demonstrate that mGluR5 overexpression in the mPFC or vHPC was proresilient while the mGluR5 knockdown was prosusceptible and that the proresilient effects of mGluR5 are mediated through distinctive downstream signaling pathways in the mPFC and vHPC. CONCLUSIONS: These findings identify mGluR5 in the mPFC and vHPC that receive BLA inputs as a critical mediator of stress resilience, highlighting circuit-specific signaling for depressive-like behaviors.