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Previous studies have suggested that specific fronto-striatal circuits are associated with impaired motor response inhibition in patients with obsessive-compulsive disorder (OCD) and their relatives. However, no study has investigated the underlying resting-state network associated with motor response inhibition in the unaffected first-degree relatives of patients with OCD. We measured motor response inhibition using stop-signal task, and obtained resting-state fMRI in 23 first-degree relatives and 52 healthy control participants. We explored the group differences in the functional network from seed regions-of-interest (ROIs) associated with motor response inhibition abilities. We used the inferior frontal gyrus (IFG) and pre-supplementary motor area (pre-SMA) as seed-ROIs. A significant group difference was observed in functional connectivity between the pre-SMA and inferior parietal lobule. In the relative group, reduced functional connectivity between these areas was associated with a longer stop-signal reaction time. Additionally, relatives showed significantly greater functional connectivity between the IFG and SMA, precentral, and postcentral areas. Our results could provide new insights into the resting-state neural activity of the pre-SMA underlying impaired motor response inhibition of unaffected first-degree relatives. In addition, our results suggested that relatives have an altered connectivity of the sensorimotor region, similar to that of patients with OCD shown in previous literature.
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Córtex Motor , Transtorno Obsessivo-Compulsivo , Humanos , Córtex Motor/diagnóstico por imagem , Mapeamento Encefálico , Vias Neurais/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/genética , Lobo Parietal/diagnóstico por imagem , Imageamento por Ressonância MagnéticaRESUMO
Gyrification patterns reflect early neurodevelopment and could be highly heritable. While some discrepant results have been reported, the most consistent finding was that patients with obsessive-compulsive disorder showed altered gyrification patterns in the orbitofrontal cortex. Nevertheless, no study has investigated the alterations in gyrification in unaffected first-degree relatives of patients with obsessive-compulsive disorder. We measured local gyrification by the FreeSurfer software in 23 unaffected first-degree relatives of patients with obsessive-compulsive disorder and 52 healthy control participants. We explored differences in the local gyrification index using vertex-wise whole-brain analysis and a region of interest-based approach in the medial and lateral orbitofrontal cortex. There was no significant difference in the local gyrification index between the 2 groups in the vertex-wise whole-brain analysis. Region of interest analyses showed that, compared with healthy controls, first-degree relatives showed significantly reduced local gyrification index in the left medial and lateral orbitofrontal cortex. A negative correlation was observed between the reduced local gyrification index in lateral orbitofrontal cortex and the subclinical anxiety scores of first-degree relatives. Our results showed that first-degree relatives of patients with obsessive-compulsive disorder had an altered local gyrification index in the orbitofrontal cortex. Especially, reduced local gyrification index in lateral orbitofrontal cortex associated with subclinical anxiety symptom could be a potential neurodevelopmental marker for the illness onset.
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Imageamento por Ressonância Magnética , Transtorno Obsessivo-Compulsivo , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/genética , EncéfaloRESUMO
Recent evidence suggests that presupplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) play an important role in response inhibition. However, no study has investigated the relationship between these brain networks at resting-state and response inhibition in obsessive-compulsive disorder (OCD). We performed resting-state functional magnetic resonance imaging scans and then measured the response inhibition of 41 medication-free OCD patients and 49 healthy control (HC) participants by using the stop-signal task outside the scanner. We explored the differences between OCD and HC groups in the functional connectivity of pre-SMA and IFG associated with the ability of motor response inhibition. OCD patients showed a longer stop-signal reaction time (SSRT). Compared to HC, OCD patients exhibit different associations between the ability of motor response inhibition and the functional connectivity between pre-SMA and IFG, inferior parietal lobule, dorsal anterior cingulate cortex, insula, and anterior prefrontal cortex. Additional analysis to investigate the functional connectivity difference from the seed ROIs to the whole brain voxels revealed that, compared to HC, OCD exhibited greater functional connectivity between pre-SMA and IFG. Also, this functional connectivity was positively correlated with the SSRT score. These results provide additional insight into the characteristics of the resting-state functional connectivity of the regions belonging to the cortico-striato-thalamo-cortical circuit and the cingulo-opercular salience network, underlying the impaired motor response inhibition of OCD. In particular, we emphasize the importance of altered functional connectivity between pre-SMA and IFG for the pathophysiology of motor response inhibition in OCD.
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Córtex Cerebral/fisiopatologia , Conectoma , Corpo Estriado/fisiopatologia , Inibição Psicológica , Atividade Motora/fisiologia , Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Tálamo/fisiopatologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adulto JovemRESUMO
The synthesis and catalytic activity of pyridine-fused triazolylidene as a novel abnormal N-heterocyclic carbene (aNHC) ligand is described. The evaluation of physical properties using X-ray crystallographic analysis and infrared spectroscopy revealed that these triazolylidenes have a high electron-donating ability toward the metal center. The application of this triazolylidene to the palladium-catalyzed cross-coupling of chloroarenes and nitroarenes with arylboronic acids showcased its ability to activate C-Cl and C-NO2 bonds.
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The layered structures of graphite and related nanographene molecules play key roles in their physical and electronic functions. However, the stacking modes of negatively curved nanographenes remain unclear, owing to the lack of suitable nanographene molecules. Herein, we report the synthesis and one-dimensional supramolecular self-assembly of negatively curved nanographenes without any assembly-assisting substituents. This curved nanographene self-assembles in various organic solvents and acts as an efficient gelator. The formation of nanofibers was confirmed by microscopic measurements, and an unprecedented double-helix assembly by continuous π-π stacking was uncovered by three-dimensional electron crystallography. This work not only reports the discovery of an all-sp2-carbon supramolecular π-organogelator with negative curvature but also demonstrates the power of three-dimensional electron crystallography for the structural determination of submicrometer-sized molecular alignment.
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The first examples of single crystals exhibiting salient effects by different structure change mechanisms are reported. The crystals of newly prepared aryl(9-isocyanoanthracene)gold(I) complexes jump in response to two different external stimuli: ultraviolet (UV) irradiation and cooling. The photosalient effect is triggered by photodimerization reaction of the anthracene moieties under photoirradiation. By contrast, the thermosalient effect is caused by anisotropic thermal contraction upon cooling without a chemical structure change. By taking advantage of the multiple-jump feature, we also show sequential jumps of crystals by cooling and then UV irradiation for demonstration of the programmed motion of molecular crystals.
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The stepwise chemical reduction of a molecular warped nanographene (WNG) having a negatively curved π-surface and defined C80 H30 composition with Cs metal used as the reducing and complexing agent allowed the isolation of three different reduced states with one, two, and three electrons added to its π-conjugated system. This provided a unique series of nanosized carbanions with increasing negative charge for in-depth structural analysis of consequences of controlled electron charging of non-planar nanographenes, using X-ray crystallographic and computational tools. The 3D molecular electrostatic potential (MEP) maps identified the negative charge localization at the central part of the WNG surface where selective coordination of Cs+ ions is confirmed crystallographically. In-depth theoretical investigation revealed a complex response of the WNG to the stepwise electron acquisition. The extended and contorted π-surface of the WNG undergoes subtle swinging distortions that are accompanied by notable changes in the electronic structure and site-dependent aromaticity of the resulting carbanions.
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Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium-catalyzed six-fold C-H borylation of HBC was successfully achieved by screening solvents. The crystal structure of hexaborylated HBC was confirmed via X-ray crystallography. Optoelectronic properties of the thus-obtained hexaborylated HBC were analyzed with the support of density functional theory calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the σ-donation of boryl groups.
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The synthesis and structural analysis of a quintuple [6]helicene with a corannulene core is reported. The compound was synthesized from corannulene in three steps including a five-fold intramolecular direct arylation. X-ray crystallographic analysis revealed a C5 -symmetric propeller-shaped structure and one-dimensional alignment in the solid state. The enantiomers of the quintuple [6]helicene were successfully separated by HPLC, and the chirality of the two fractions was identified by CD spectroscopy. A kinetic study yielded a racemization barrier of 34.2â kcal mol-1 , which is slightly lower than that of pristine [6]helicene. DFT calculations indicate a rapid bowl-to-bowl inversion of the corannulene moiety and a step-by-step chiral inversion pathway for the five [6]helicene moieties.
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Obesity is often accompanied by hyperuricemia. However, purine metabolism in various tissues, especially regarding uric acid production, has not been fully elucidated. Here we report, using mouse models, that adipose tissue could produce and secrete uric acid through xanthine oxidoreductase (XOR) and that the production was enhanced in obesity. Plasma uric acid was elevated in obese mice and attenuated by administration of the XOR inhibitor febuxostat. Adipose tissue was one of major organs that had abundant expression and activities of XOR, and adipose tissues in obese mice had higher XOR activities than those in control mice. 3T3-L1 and mouse primary mature adipocytes produced and secreted uric acid into culture medium. The secretion was inhibited by febuxostat in a dose-dependent manner or by gene knockdown of XOR. Surgical ischemia in adipose tissue increased local uric acid production and secretion via XOR, with a subsequent increase in circulating uric acid levels. Uric acid secretion from whole adipose tissue was increased in obese mice, and uric acid secretion from 3T3-L1 adipocytes was increased under hypoxia. Our results suggest that purine catabolism in adipose tissue could be enhanced in obesity.
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Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Obesidade/metabolismo , Ácido Úrico/metabolismo , Xantina Desidrogenase/metabolismo , Células 3T3-L1 , Adipócitos/patologia , Tecido Adiposo/patologia , Animais , Hipóxia Celular , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Obesos , Obesidade/genética , Obesidade/patologia , Xantina Desidrogenase/genéticaRESUMO
Background: Hoarding disorder (HD) is characterized by cognitive control impairments and abnormal brain activity in the insula and anterior cingulate cortex (ACC) during disposal of personal items or certain executive function tasks. However, whether there are any changes in resting-state functional connectivity of the insula and ACC remains unclear. Methods: A total of 55 subjects, including 24 patients with HD and 31 healthy controls (HCs), participated in the study. We acquired resting-state functional magnetic resonance imaging data and examined group differences in functional connectivity from the insula and ACC in whole-brain voxels. Results: In patients with HD, functional connectivity was significantly lower between the right insula and right inferior frontal gyrus (IFG) and left superior temporal gyrus (STG) compared to HCs. There was no correlation between these connectivities and HD symptoms. Conclusions: Although the clinical implication is uncertain, our results suggest that patients with HD have resting-state functional alterations between the insula and IFG and STG, corresponding with the results of previous fMRI studies. These findings provide new insight into the neurobiological basis of HD.
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Background: Patients with obsessive-compulsive disorder (OCD) have deficits in decision-making in the Iowa Gambling Task (IGT). However, no study has investigated the parameters of the prospect valence learning (PVL) model in the IGT for OCD. Aims: This study aimed to investigate deficits in decision-making in OCD using the PVL model and identify whether the parameters of the PVL model were associated with obsessive-compulsive severity. Methods: Forty-seven medication-free patients with OCD were compared with 47 healthy controls (HCs). Decision-making was measured using the total net and block net scores of the IGT. A PVL model with a decay-reinforcement learning rule (PVL-DecayRI) was used to investigate the parameters of the model. Correlation analysis was conducted between each parameter of the PVL-DecayRL and obsessive-compulsive symptoms. Results: The total net score of patients with OCD was significantly lower than that of the HCs. The block net scores of the OCD group did not differ across the five blocks, whereas in the HCs, the fifth block net score was significantly higher than the block net scores of the first and second blocks. The values of the recency and response consistency parameters of the PVL-DecayRI in patients with OCD were significantly lower than those in HCs. The recency parameter positively correlated with the Y-BOCS obsessive score. Meanwhile, there was no correlation between consistency parameter values and symptom severity in OCD. Conclusion: Our detailed analysis of the decision-making deficit in OCD suggests that the most recent outcome has a small influence on the expectancy of prospect valence, as indicated by the lower recency parameter, and is characterized by more impulsive choices, as indicated by the lower consistency parameter.
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Recent evidence suggests that broad brain regions, not limited to the fronto-striato-thalamo-cortical circuit, play an important role in motor response inhibition. However, it is still unclear which specific key brain region is responsible for impaired motor response inhibition observed in obsessive-compulsive disorder (OCD). We calculated the fractional amplitude of low-frequency fluctuations (fALFF) and measured response inhibition ability using the stop-signal task in 41 medication-free patients with OCD and 49 healthy control (HC) participants. We explored the brain region that shows different association between the fALFF and the ability of motor response inhibition. Significant differences in fALFF associated with the ability of motor response inhibition were identified in dorsal posterior cingulate cortex (PCC). There was a positive correlation between increased fALFF in the dorsal PCC and impaired motor response inhibition in OCD. In the HC group, there was a negative correlation between the two variables. Our results suggest that the magnitude of resting-state blood oxygen level-dependent oscillation of the dorsal PCC is a key brain region for the underlying mechanisms of impaired motor response inhibition in OCD. Future studies should examine whether this characteristic of dorsal PCC affects other large-scale networks responsible for motor response inhibition of OCD.
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Giro do Cíngulo , Transtorno Obsessivo-Compulsivo , Humanos , Giro do Cíngulo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo , Mapeamento Encefálico/métodos , Transtorno Obsessivo-Compulsivo/diagnóstico por imagemRESUMO
Ca(2+) signaling mediated by phospholipase C that produces inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] and diacylglycerol (DAG) controls lymphocyte activation. In contrast to store-operated Ca(2+) entry activated by Ins(1,4,5)P(3)-induced Ca(2+) release from endoplasmic reticulum, the importance of DAG-activated Ca(2+) entry remains elusive. Here, we describe the physiological role of DAG-activated Ca(2+) entry channels in B-cell receptor (BCR) signaling. In avian DT40 B cells, deficiency of transient receptor potential TRPC3 at the plasma membrane (PM) impaired DAG-activated cation currents and, upon BCR stimulation, the sustained translocation to the PM of protein kinase Cbeta (PKCbeta) that activated extracellular signal-regulated kinase (ERK). Notably, TRPC3 showed direct association with PKCbeta that maintained localization of PKCbeta at the PM. Thus, TRPC3 functions as both a Ca(2+)-permeable channel and a protein scaffold at the PM for downstream PKCbeta activation in B cells.
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Linfócitos B/enzimologia , Sinalização do Cálcio , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína Quinase C/metabolismo , Canais de Cátion TRPC/metabolismo , Animais , Linfócitos B/citologia , Canais de Cálcio/metabolismo , Linhagem Celular , Membrana Celular/enzimologia , Galinhas , Diglicerídeos/metabolismo , Ativação Enzimática , Células HeLa , Humanos , Ativação do Canal Iônico , Camundongos , Modelos Biológicos , Fatores de Transcrição NFATC/metabolismo , Ligação Proteica , Proteína Quinase C beta , Transporte Proteico , Receptores de Antígenos de Linfócitos B/metabolismoRESUMO
Canonical transient receptor potential (TRPC) channels control influxes of Ca(2+) and other cations that induce diverse cellular processes upon stimulation of plasma membrane receptors coupled to phospholipase C (PLC). Invention of subtype-specific inhibitors for TRPCs is crucial for distinction of respective TRPC channels that play particular physiological roles in native systems. Here, we identify a pyrazole compound (Pyr3), which selectively inhibits TRPC3 channels. Structure-function relationship studies of pyrazole compounds showed that the trichloroacrylic amide group is important for the TRPC3 selectivity of Pyr3. Electrophysiological and photoaffinity labeling experiments reveal a direct action of Pyr3 on the TRPC3 protein. In DT40 B lymphocytes, Pyr3 potently eliminated the Ca(2+) influx-dependent PLC translocation to the plasma membrane and late oscillatory phase of B cell receptor-induced Ca(2+) response. Moreover, Pyr3 attenuated activation of nuclear factor of activated T cells, a Ca(2+)-dependent transcription factor, and hypertrophic growth in rat neonatal cardiomyocytes, and in vivo pressure overload-induced cardiac hypertrophy in mice. These findings on important roles of native TRPC3 channels are strikingly consistent with previous genetic studies. Thus, the TRPC3-selective inhibitor Pyr3 is a powerful tool to study in vivo function of TRPC3, suggesting a pharmaceutical potential of Pyr3 in treatments of TRPC3-related diseases such as cardiac hypertrophy.
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Pirazóis/farmacologia , Canais de Cátion TRPC/antagonistas & inibidores , Amidas , Animais , Linfócitos B , Cálcio/metabolismo , Linhagem Celular , Hipertrofia/tratamento farmacológico , Camundongos , Miócitos Cardíacos/patologia , Fatores de Transcrição NFATC/efeitos dos fármacos , Fatores de Transcrição NFATC/metabolismo , Transporte Proteico/efeitos dos fármacos , Pirazóis/química , Ratos , Relação Estrutura-Atividade , Fosfolipases Tipo C/efeitos dos fármacos , Fosfolipases Tipo C/metabolismoRESUMO
A deoxygenative transformation of diarylketones leading to multiply arylated alkanes was developed. Diarylketones were reacted with diphenylphosphine oxide resulting in a phospha-Brook rearrangement, followed by palladium-catalyzed cross-couplings or a Friedel-Crafts type alkylation to afford the corresponding multiply arylated alkanes. A variety of diarylketones can be converted to multiply arylated alkanes such as diarylmethanes, tetraarylethanes, and triarylmethanes by reduction, dimerization, and arylation in one pot. Furthermore, a one-pot conversion from arylcarboxylic acids to diarylmethanes and tetraarylethanes, and a synthesis of tetraarylmethane and triphenylethane using sequential coupling reactions are also presented.
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We have discovered a ring-opening fluorination of bicyclic azaarenes. Upon treatment of bicyclic azaarenes such as pyrazolo[1,5-a]pyridines with electrophilic fluorinating agents, fluorination of the aromatic ring is followed by a ring-opening reaction. Although this overall transformation can be classified as an electrophilic fluorination of an aromatic ring, it is a novel type of fluorination that results in construction of tertiary carbon-fluorine bonds. The present protocol can be applied to a range of bicyclic azaarenes, tolerating azines and a variety of functional groups. Additionally, mechanistic studies and enantioselective fluorination have been examined.
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Background: Symptoms of obsessive-compulsive disorder (OCD) have been conceptualized as manifestations of decision-making deficits. Patients with OCD exhibit impairment during the decision-making process, as assessed by the Iowa Gambling Task (IGT). This impairment is independent of clinical severity and disease progression. However, the association between the decision-making deficit and resting-state brain activity of patients with OCD has not been examined. Methods: Fifty unmedicated patients with OCD and 55 matched control subjects completed IGT. Resting-state brain activity was examined using the fractional amplitude of low-frequency fluctuations (fALFFs). fALFF analysis focused on the slow-4 and 5 bands. Group comparisons were performed to determine the association between IGT performance and fALFFs. Results: There was a significant group difference in the association between the IGT total net score and slow-4 fALFFs in the left putamen (voxel height threshold of p < 0.001; cluster size threshold of p < 0.05; family wise error-corrected). Higher putamen slow-4 fALFFs were correlated with lower IGT scores for OCD patients (r = -0.485; p < 0.0005) and higher IGT scores for control subjects (r = 0.402; p < 0.005). There was no group difference in the association between the IGT total net score and slow-5 fALFFs. Conclusions: These findings in unmedicated patients demonstrate the importance of resting-state putamen activity for decision-making deficit associated with OCD, as measured by IGT. The inverse correlation may be explained by the hypersensitive response of the putamen in patients with OCD.
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Although preliminary neuroimaging research suggests that patients with hoarding disorder (HD) show widespread abnormal task-related activity in the brain, there has been no research on alterations in the white matter tracts in these patients. The aim of this study was to investigate the characteristics of the major white matter tracts in patients with HD. Tract-based spatial statistics were used to search for white matter tract abnormalities throughout the brain in 25 patients with HD and 36 healthy controls. Post hoc analysis of regions of interest was performed to detect correlations with clinical features. Compared with the controls, patients with HD showed decreased fractional anisotropy and increased radial diffusivity in anatomically widespread white matter tracts. Post hoc analysis of regions of interest revealed a significant negative correlation between the severity of hoarding symptoms and fractional anisotropy in the left anterior limb of the internal capsule and a positive correlation between the severity of these symptoms and radial diffusivity in the right anterior thalamic radiation. Patients with HD showed a broad range of alterations in the frontal white matter tracts, including the frontothalamic circuit, frontoparietal network, and frontolimbic pathway. The findings of this study indicate associations between frontal white matter abnormalities related to the severity of hoarding symptoms in HD and the cortical regions involved in cognitive dysfunction. The insights provided would be useful for understanding the neurobiological basis of HD.
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Transtorno de Acumulação , Substância Branca , Anisotropia , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Transtorno de Acumulação/diagnóstico por imagem , Humanos , Substância Branca/diagnóstico por imagemRESUMO
Background It is gradually becoming clear that obsessive-compulsive disorder (OCD) patients have aberrant resting-state large-scale intrinsic networks of cingulo-opercular salience (SN), default mode (DMN), and front-parietal network (FPN). However, it remains unknown whether unaffected first-degree relatives of OCD patients have these alterations as a vulnerability marker to the disorder. Methods We performed resting-state functional magnetic resonance imaging (rsfMRI) scans of 47 medication-free OCD patients, 21 unaffected healthy first-degree relatives of OCD patients, and 62 healthy control (HC) participants. We explored differences between the three groups in the functional connectivity from SN (seeds: anterior-insula (AI) and dorsal anterior cingulate cortex (dACC)), DMN (seeds: medial prefrontal cortex (MPFC) and posterior parietal cortex (PCC)), and FPN (seeds: dorsolateral prefrontal cortex (DLPFC)). Results Compared to HC, both OCD patients and first-degree relatives showed significantly greater functional connectivity between AI and PCC and between DLPFC and the thalamus. Compared to first-degree relatives and HC, OCD patients showed reduced functional connectivity between PCC and DLPFC, and this altered functional connectivity was negatively correlated with anxiety and depressive symptom within OCD group. Conclusions OCD patients and unaffected first-degree relatives of OCD patients showed overlapping alterations in resting state functional connectivity between the regions of SN and DMN and between DLPFC and the thalamus. Our results suggested that alterations between large-scale intrinsic networks and within the dorsal cognitive cortico-striato-thalamo-cortical (CSTC) circuit could represent endophenotype markers of OCD.