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Quantitative Imaging in Medicine and... Apr 2023Cholinergic basal forebrain (BF) pathology is a hallmark of Parkinson's disease (PD) with mild cognitive impairment (PD-MCI). Assessment of functional connectivity (FC)...
BACKGROUND
Cholinergic basal forebrain (BF) pathology is a hallmark of Parkinson's disease (PD) with mild cognitive impairment (PD-MCI). Assessment of functional connectivity (FC) of different cholinergic BF nuclei may deepen the understanding of PD-MCI pathogenesis.
METHODS
Seed-based FC analysis was performed with bilateral medial septal nucleus, the nucleus of the vertical limb of the diagonal band, nucleus of the horizontal limb of the diagonal band (Ch1-3), and the nucleus basalis of Meynert (NBM/Ch4) to explore the BF functional alterations in different frequency bands. Correlations between FC values of abnormal regions and scores of cognitive domains and depression in the PD group were also assessed.
RESULTS
For the right Ch4, in the conventional frequency band, the PD-MCI group exhibited lower FC values in the right middle cingulate and paracingulate gyri, middle frontal gyrus, left inferior parietal gyrus, and superior frontal gyrus compared with healthy controls (HC), and in the left calcarine fissure and surrounding cortex compared with PD with normal cognition (PD-NC). For the slow 4 subbands, the PD-MCI group showed significantly lower FC values in the left putamen, middle frontal gyrus, right middle frontal gyrus, and precuneus compared with HC, and in right middle frontal gyrus cingulate and paracingulate gyri compared with the PD-NC group. For the slow 5 subbands, the PD-MCI group showed increased FC values in the right calcarine fissure and surrounding cortex, and left cerebellum. For the left Ch1-3, FC values in the right middle cingulate and paracingulate gyri were lower in patients with PD-MCI than in the PD-NC group in slow 4 subbands. Furthermore, altered FC values in the cortical regions for Ch4 seed were possibly correlated with depression and different cognitive domain scores.
CONCLUSIONS
The study identified an imbalanced association between different cholinergic BF nuclei and cortical regions in patients with PD-MCI, and showed that FC changes are frequency-specific, which may provide new insights into functional alterations within the cholinergic system in cognitive impairment associated with PD.
PubMed: 37064391
DOI: 10.21037/qims-22-582 -
The Journal of Neuroscience : the... May 2023The bed nucleus of the stria terminalis (BNST) has been implicated in a variety of social behaviors, including aggression, maternal care, mating behavior, and social...
The bed nucleus of the stria terminalis (BNST) has been implicated in a variety of social behaviors, including aggression, maternal care, mating behavior, and social interaction. Limited evidence from rodent studies suggests that activation of the BNST results in a decrease in social interaction between unfamiliar animals. The role of the BNST in social interaction in primates remains wholly unexamined. Nonhuman primates provide a valuable model for studying social behavior because of both their rich social repertoire and neural substrates of behavior with high translational relevance to humans. To test the hypothesis that the primate BNST is a critical modulator of social behavior, we performed intracerebral microinfusions of the GABA agonist muscimol to transiently inactivate the BNST in male macaque monkeys. We measured changes in social interaction with a familiar same-sex conspecific. Inactivation of the BNST resulted in significant increase in total social contact. This effect was associated with an increase in passive contact and a significant decrease in locomotion. Other nonsocial behaviors (sitting passively alone, self-directed behaviors, and manipulation) were not impacted by BNST inactivation. As part of the "extended amygdala," the BNST is highly interconnected with the basolateral (BLA) and central (CeA) nuclei of the amygdala, both of which also play critical roles in regulating social interaction. The precise pattern of behavioral changes we observed following inactivation of the BNST partially overlaps with our prior reports in the BLA and CeA. Together, these data demonstrate that the BNST is part of a network regulating social behavior in primates. The bed nucleus of the stria terminalis (BNST) has a well-established role in anxiety behaviors, but its role in social behavior is poorly understood. No prior studies have evaluated the impact of BNST manipulations on social behavior in primates. We found that transient pharmacological inactivation of the BNST increased social behavior in pairs of macaque monkeys. These data suggest the BNST contributes to the brain networks regulating sociability.
Topics: Humans; Animals; Male; Macaca mulatta; Septal Nuclei; Social Behavior; Amygdala; Aggression
PubMed: 37012054
DOI: 10.1523/JNEUROSCI.2090-22.2023 -
Nature Communications Mar 2023Binge alcohol consumption induces discrete social and arousal disturbances in human populations that promote increased drinking and accelerate the progression of Alcohol...
Binge alcohol consumption induces discrete social and arousal disturbances in human populations that promote increased drinking and accelerate the progression of Alcohol Use Disorder. Here, we show in a mouse model that binge alcohol consumption disrupts social recognition in females and potentiates sensorimotor arousal in males. These negative behavioral outcomes were associated with sex-specific adaptations in serotonergic signaling systems within the lateral habenula (LHb) and the bed nucleus of the stria terminalis (BNST), particularly those related to the receptor 5HT. While both BNST and LHb neurons expressing this receptor display potentiated activation following binge alcohol consumption, the primary causal mechanism underlying the effects of alcohol on social and arousal behaviors appears to be excessive activation of LHb neurons. These findings may have valuable implications for the development of sex-specific treatments for mood and alcohol use disorders targeting the brain's serotonin system.
Topics: Humans; Male; Female; Mice; Animals; Alcoholism; Binge Drinking; Serotonin; Neurons; Alcohol Drinking; Arousal; Ethanol; Septal Nuclei
PubMed: 37002196
DOI: 10.1038/s41467-023-36808-2 -
Frontiers in Neural Circuits 2023The vast majority of studies on hippocampal rhythms have been conducted on animals or humans in situations where their attention was focused on external stimuli or... (Review)
Review
The vast majority of studies on hippocampal rhythms have been conducted on animals or humans in situations where their attention was focused on external stimuli or solving cognitive tasks. These studies formed the basis for the idea that rhythmical activity coordinates the work of neurons during information processing. However, at rest, when attention is not directed to external stimuli, brain rhythms do not disappear, although the parameters of oscillatory activity change. What is the functional load of rhythmical activity at rest? Hippocampal oscillatory activity during rest is called the non-theta state, as opposed to the theta state, a characteristic activity during active behavior. We dedicate our review to discussing the present state of the art in the research of the non-theta state. The key provisions of the review are as follows: (1) the non-theta state has its own characteristics of oscillatory and neuronal activity; (2) hippocampal non-theta state is possibly caused and maintained by change of rhythmicity of medial septal input under the influence of raphe nuclei; (3) there is no consensus in the literature about cognitive functions of the non-theta-non-ripple state; and (4) the antagonistic relationship between theta and delta rhythms observed in rodents is not always observed in humans. Most attention is paid to the non-theta-non-ripple state, since this aspect of hippocampal activity has not been investigated properly and discussed in reviews.
Topics: Animals; Humans; Theta Rhythm; Hippocampus; Neurons; Attention; Cognition
PubMed: 36960401
DOI: 10.3389/fncir.2023.1134705 -
Brain Stimulation 2023
Topics: Humans; Septal Nuclei; Deep Brain Stimulation; Thalamus; Obsessive-Compulsive Disorder
PubMed: 36958600
DOI: 10.1016/j.brs.2023.03.010 -
Neuropsychopharmacology : Official... Jun 2023The bed nucleus of the stria terminalis (BNST) is a critical mediator of stress responses and anxiety-like behaviors. Neurons expressing protein kinase C delta (BNST)...
The bed nucleus of the stria terminalis (BNST) is a critical mediator of stress responses and anxiety-like behaviors. Neurons expressing protein kinase C delta (BNST) are an abundant but understudied subpopulation implicated in inhibiting feeding, but which have conflicting reports about their role in anxiety-like behaviors. We have previously shown that expression of PKCδ is dynamically regulated by stress and that BNST cells are recruited during bouts of active stress coping. Here, we first show that in vivo activation of this population is mildly aversive. This aversion was insensitive to prior restraint stress exposure. Further investigation revealed that unlike other BNST subpopulations, BNST cells do not exhibit increased cfos expression following restraint stress. Ex vivo current clamp recordings also indicate they are resistant to firing. To elucidate their afferent control, we next used rabies tracing with whole-brain imaging and channelrhodopsin-assisted circuit mapping, finding that BNST cells receive abundant input from affective, arousal, and sensory regions including the basolateral amygdala (BLA) paraventricular thalamus (PVT) and central amygdala PKCδ-expressing cells (CeA). Given these findings, we used in vivo optogenetics and fiber photometry to further examine BNST cells in the context of stress and anxiety-like behavior. We found that BNST cell activity is associated with increased anxiety-like behavior in the elevated plus maze, increases following footshock, and unlike other BNST subpopulations, does not desensitize to repeated stress exposure. Taken together, we propose a model in which BNST cells may serve as threat detectors, integrating exteroceptive and interoceptive information to inform stress coping behaviors.
Topics: Septal Nuclei; Anxiety; Central Amygdaloid Nucleus; Neurons; Affect
PubMed: 36941364
DOI: 10.1038/s41386-023-01569-5 -
Journal of Traumatic Stress Apr 2023Posttraumatic stress disorder (PTSD) significantly impacts many veterans. Although PTSD has been linked to alterations in the fear brain network, the disorder likely...
Posttraumatic stress disorder (PTSD) significantly impacts many veterans. Although PTSD has been linked to alterations in the fear brain network, the disorder likely involves alterations in both the fear and anxiety networks. Fear involves responses to imminent, predictable threat and is driven by the amygdala, whereas anxiety involves responses to potential, unpredictable threat and engages the bed nucleus of the stria terminalis (BNST). The BNST has been implicated in PTSD, but the role of the BNST in combat veterans with PTSD has yet to be examined. Identifying alterations in BNST responses to unpredictable threat could provide important new targets for treatment. The current study examined whether veterans with PTSD have altered BNST or amygdala responses (function and connectivity) to unpredictable and predictable threat. The fMRI task involved viewing predictable threat cues followed by threat images, predictable neutral cues followed by neutral images, and unpredictable threat cues followed by either a threat or neutral image. Participants included 32 combat-exposed veterans with PTSD and 13 combat-exposed controls without PTSD. Across all conditions, veterans with PTSD had heightened BNST activation and displayed stronger BNST and amygdala connectivity with multiple fear and anxiety regions (hypothalamus, hippocampus, insula, ventromedial prefrontal cortex) relative to controls. In contrast, combat controls showed a pattern of stronger connectivity during neutral conditions (e.g., BNST-vmPFC), which may suggest a neural signature of resilience to developing PTSD, η = .087-.527, ps < .001. These findings have implications for understanding fear and anxiety networks that may contribute to the development and maintenance of PTSD.
Topics: Humans; Stress Disorders, Post-Traumatic; Septal Nuclei; Veterans; Anxiety; Amygdala
PubMed: 36938747
DOI: 10.1002/jts.22918 -
International Journal of Molecular... Feb 2023Although antipsychotics' mechanisms of action have been thoroughly investigated, they have not been fully elucidated at the network level. We tested the hypothesis that...
Although antipsychotics' mechanisms of action have been thoroughly investigated, they have not been fully elucidated at the network level. We tested the hypothesis that acute pre-treatment with ketamine (KET) and administration of asenapine (ASE) would modulate the functional connectivity of brain areas relevant to the pathophysiology of schizophrenia, based on transcript levels of , an immediate early gene encoding a key molecule of the dendritic spine. Sprague-Dawley rats ( = 20) were assigned to KET (30 mg/kg) or vehicle (VEH). Each pre-treatment group ( = 10) was randomly split into two arms, receiving ASE (0.3 mg/kg), or VEH. mRNA levels were evaluated by in situ hybridization in 33 regions of interest (ROIs). We computed all possible pairwise Pearson correlations and generated a network for each treatment group. Acute KET challenge was associated with negative correlations between the medial portion of cingulate cortex/indusium griseum and other ROIs, not detectable in other treatment groups. KET/ASE group showed significantly higher inter-correlations between medial cingulate cortex/indusium griseum and lateral putamen, the upper lip of the primary somatosensory cortex, septal area nuclei, and claustrum, in comparison to the KET/VEH network. ASE exposure was associated with changes in subcortical-cortical connectivity and an increase in centrality measures of the cingulate cortex and lateral septal nuclei. In conclusion, ASE was found to finely regulate brain connectivity by modelling the synaptic architecture and restoring a functional pattern of interregional co-activation.
Topics: Rats; Animals; Antipsychotic Agents; Rats, Sprague-Dawley; Post-Synaptic Density; Connectome; Genes, Immediate-Early; Ketamine
PubMed: 36901803
DOI: 10.3390/ijms24054372 -
Alterations in BNST Intrinsic Functional Connectivity in Early Abstinence from Alcohol Use Disorder.Alcohol and Alcoholism (Oxford,... May 2023Maintaining abstinence from alcohol use disorder (AUD) is extremely challenging, partially due to increased symptoms of anxiety and stress that trigger relapse. Rodent...
AIMS
Maintaining abstinence from alcohol use disorder (AUD) is extremely challenging, partially due to increased symptoms of anxiety and stress that trigger relapse. Rodent models of AUD have identified that the bed nucleus of the stria terminalis (BNST) contributes to symptoms of anxiety-like behavior and drug-seeking during abstinence. In humans, however, the BNST's role in abstinence remains poorly understood. The aims of this study were to assess BNST network intrinsic functional connectivity in individuals during abstinence from AUD compared to healthy controls and examine associations between BNST intrinsic functional connectivity, anxiety and alcohol use severity during abstinence.
METHODS
The study included resting state fMRI scans from participants aged 21-40 years: 20 participants with AUD in abstinence and 20 healthy controls. Analyses were restricted to five pre-selected brain regions with known BNST structural connections. Linear mixed models were used to test for group differences, with sex as a fixed factor given previously shown sex differences.
RESULTS
BNST-hypothalamus intrinsic connectivity was lower in the abstinent group relative to the control group. There were also pronounced sex differences in both the group and individual analyses; many of the findings were specific to men. Within the abstinent group, anxiety was positively associated with BNST-amygdala and BNST-hypothalamus connectivity, and men, not women, showed a negative relationship between alcohol use severity and BNST-hypothalamus connectivity.
CONCLUSIONS
Understanding differences in connectivity during abstinence may help explain the clinically observed anxiety and depression symptoms during abstinence and may inform the development of individualized treatments.
Topics: Humans; Male; Female; Alcoholism; Septal Nuclei; Anxiety; Magnetic Resonance Imaging; Amygdala
PubMed: 36847484
DOI: 10.1093/alcalc/agad006 -
British Journal of Anaesthesia May 2023Sepsis-associated encephalopathy is characterised by cognitive dysfunction, and might be mediated by deficits in neurotransmission. Reduced cholinergic neurotransmission...
BACKGROUND
Sepsis-associated encephalopathy is characterised by cognitive dysfunction, and might be mediated by deficits in neurotransmission. Reduced cholinergic neurotransmission in the hippocampus impairs memory function. We assessed real-time alterations of acetylcholine neurotransmission from the medial septal nucleus to the hippocampus, and explored whether sepsis-induced cognitive deficits can be relieved by activating upstream cholinergic projections.
METHOD
Lipopolysaccharide (LPS) injection or caecal ligation and puncture (CLP) was used to induce sepsis and associated neuroinflammation in wild-type and mutant mice. Adeno-associated viruses for calcium and acetylcholine imaging, and for optogenetic and chemogenetic modulation of cholinergic neurones were injected into the hippocampus or medial septum, and a 200-μm-diameter optical fibre was implanted to collect acetylcholine and calcium signals. Cholinergic activity of the medial septum was manipulated and combined with cognitive assessment after LPS injection or CLP.
RESULTS
Intracerebroventricular LPS injection reduced postsynaptic acetylcholine (from 0.146 [0.001] to 0.0047 [0.0005]; p=0.004) and calcium (from 0.0236 [0.0075] to 0.0054 [0.0026]; p=0.0388) signals in hippocampal Vglut2-positive glutamatergic neurones, whereas optogenetic activation of cholinergic neurones in the medial septum reversed LPS-induced reductions in these two signals. Intraperitoneal LPS injection decreased acetylcholine concentration in the hippocampus (476 [20] pg ml to 382 [14] pg ml; p=0.0001). Reduction in long-term potentiation (238 [23] % to 150 [12] %; p=0.0082) and enhancement of hippocampal pyramidal neurone action potential frequency (5.8 [1.5] Hz to 8.2 [1.8] Hz; p=0.0343) were relieved, and neurocognitive performance was improved by chemogenetic activation of cholinergic innervation of the hippocampus 3 days after LPS injection in septic mice.
CONCLUSIONS
Systemic or local LPS reduced cholinergic neurotransmission from the medial septum to hippocampal pyramidal neurones, and their selective activation alleviated defects in hippocampal neuronal function and synaptic plasticity and ameliorated memory deficits in sepsis model mice through enhanced cholinergic neurotransmission. This provides a basis for targeting cholinergic signalling to the hippocampus in sepsis-induced encephalopathy.
Topics: Mice; Animals; Septal Nuclei; Acetylcholine; Lipopolysaccharides; Calcium; Hippocampus; Synaptic Transmission; Cognitive Dysfunction; Sepsis; Cognition; Cholinergic Agents
PubMed: 36813621
DOI: 10.1016/j.bja.2023.01.019