Stress is a prevailing risk factor for mood-related illnesses, wherein women represent the majority of those affected by major depression. Despite the growing literature suggesting that affective ...disorders can arise after a traumatic event is vicariously experienced, this relationship remains understudied in female subjects at the preclinical level. Thus, the objective of the current investigation was to examine whether exposure to emotional and/or psychological stress (ES) mediates depression-related outcomes in female mice.
Female C57BL/6 mice (8 weeks old, null parity) vicariously experienced the defeat bout of a male conspecific, by a male CD1 aggressor, for 10 consecutive days. Twenty-four hours after the last stress exposure, female mice were tested in the social interaction, sucrose preference, tail suspension, or elevated plus maze tests. Furthermore, we examined whether ketamine and chlordiazepoxide, pharmacological agents used to treat mood-related disorders in the clinical population, would reverse the ES-induced social dysfunction.
When compared with control mice, female mice exposed to ES displayed decreased social behavior and preference for sucrose, along with increased immobility in the tail suspension test. Also, they displayed higher levels of blood serum corticosterone, as well as decreased body weight. Lastly, the ES-induced avoidance-like phenotype was ameliorated by both ketamine and chlordiazepoxide.
Our data indicate that female mice exposed to ES display a behavioral and physiologic profile that mimics symptoms of depression in the clinical population. As such, this experimental model may be adopted to examine vicarious stress-induced mood-related disorders, as well as pharmacological antidepressant response, in a sex-specific manner.
Post-translational protein modifications are essential for the spatio-temporal regulation of protein function. In this study, we examine how the activity of the
AMPylase FIC-1 modulates physiological ...processes
. We find that over-expression (OE) of the constitutive AMPylase FIC-1(E274G) impairs
development, fertility, and stress resilience. We also show that FIC-1(E274G) OE inhibits pathogen avoidance behavior by selectively suppressing production of the Transforming Growth Factor-β (TGF-β) ligands DAF-7 and DBL-1 in ASI sensory neurons. Finally, we demonstrate that FIC-1 contributes to the regulation of adult body growth, cholinergic neuron function, and larval entry into dauer stage; all processes controlled by TGF-β signaling. Together, our results suggest a role for FIC-1 in regulating TGF-β signaling in
.
Social stress, including bullying during adolescence, is a risk factor for common psychopathologies such as depression. To investigate the neural mechanisms associated with juvenile social ...stress-induced mood-related endophenotypes, we examined the behavioral, morphological, and biochemical effects of the social defeat stress model of depression on hippocampal dendritic spines within the CA1 stratum radiatum. Adolescent (postnatal day 35) male C57BL/6 mice were subjected to defeat episodes for 10 consecutive days. Twenty-four h later, separate groups of mice were tested on the social interaction and tail suspension tests.
Hippocampi were then dissected and Western blots were conducted to quantify protein levels for various markers important for synaptic plasticity including protein kinase M zeta (PKMζ), protein kinase C zeta (PKCζ), the dopamine-1 (D1) receptor, tyrosine hydroxylase (TH), and the dopamine transporter (DAT). Furthermore, we examined the presence of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-receptor subunit GluA2 as well as colocalization with the post-synaptic density 95 (PSD95) protein, within different spine subtypes (filopodia, stubby, long-thin, mushroom) using an immunohistochemistry and Golgi-Cox staining technique. The results revealed that social defeat induced a depression-like behavioral profile, as inferred from decreased social interaction levels, increased immobility on the tail suspension test, and decreases in body weight. Whole hippocampal immunoblots revealed decreases in GluA2, with a concomitant increase in DAT and TH levels in the stressed group. Spine morphology analyses further showed that defeated mice displayed a significant decrease in stubby spines, and an increase in long-thin spines within the CA1 stratum radiatum. Further evaluation of GluA2/PSD95 containing-spines demonstrated a decrease of these markers within long-thin and mushroom spine types. Together, these results indicate that juvenile social stress induces GluA2- and dopamine-associated dysregulation in the hippocampus – a neurobiological mechanism potentially underlying the development of mood-related syndromes as a consequence of adolescent bullying.
The salience network, an intrinsic brain network thought to modulate attention to internal versus external stimuli, has been consistently found to be atypical in autism spectrum disorders (ASD). ...However, little is known about how this altered resting-state connectivity relates to brain activity during information processing, which has important implications for understanding sensory overresponsivity (SOR), a common and impairing condition in ASD related to difficulty downregulating brain responses to sensory stimuli. This study examined how SOR in youth with ASD relates to atypical salience network connectivity and whether these atypicalities are associated with abnormal brain response to basic sensory information.
Functional magnetic resonance imaging was used to examine how parent-rated SOR symptoms related to salience network connectivity in 61 youth (aged 8-17 years; 28 with ASD and 33 IQ-matched typically developing youth). Correlations between resting-state salience network connectivity and brain response to mildly aversive tactile and auditory stimuli were examined.
SOR in youth with ASD was related to increased resting-state functional connectivity between salience network nodes and brain regions implicated in primary sensory processing and attention. Furthermore, the strength of this connectivity at rest was related to the extent of brain activity in response to auditory and tactile stimuli.
Results support an association between intrinsic brain connectivity and specific atypical brain responses during information processing. In addition, findings suggest that basic sensory information is overly salient to individuals with SOR, leading to overattribution of attention to this information. Implications for intervention include incorporating sensory coping strategies into social interventions for individuals with SOR.
We investigated a unique way in which adolescent peer influence occurs on social media. We developed a novel functional MRI (fMRI) paradigm to simulate Instagram, a popular social photo-sharing tool, ...and measured adolescents' behavioral and neural responses to likes, a quantifiable form of social endorsement and potential source of peer influence. Adolescents underwent fMRI while viewing photos ostensibly submitted to Instagram. They were more likely to like photos depicted with many likes than photos with few likes; this finding showed the influence of virtual peer endorsement and held for both neutral photos and photos of risky behaviors (e.g., drinking, smoking). Viewing photos with many (compared with few) likes was associated with greater activity in neural regions implicated in reward processing, social cognition, imitation, and attention. Furthermore, when adolescents viewed risky photos (as opposed to neutral photos), activation in the cognitive-control network decreased. These findings highlight possible mechanisms underlying peer influence during adolescence.
Mobile social media often feature the ability to "Like" content posted by others. This study examined the effect of Likes on youths' neural and behavioral responses to photographs. High school and ...college students (N = 61, ages 13-21) viewed theirs and others' Instagram photographs while undergoing functional Magnetic Resonance Imaging (fMRI). Participants more often Liked photographs that appeared to have received many (vs. few) Likes. Popular photographs elicited greater activity in multiple brain regions, including the nucleus accumbens (NAcc), a hub of the brain's reward circuitry. NAcc responsivity increased with age for high school but not college students. When viewing images depicting risk-taking (vs. nonrisky photographs), high school students, but not college students, showed decreased activation of neural regions implicated in cognitive control.
Fishes from the northwestern Gulf of Mexico were surveyed during four oceanographic campaigns (February and October 2016, June and September 2017) using a shrimp trawl net and benthic sled net in 20 ...locations at depths that ranged from 43 to 3608 m. Length–weight relations (LWR) were estimated for 39 fish species (in alphabetical order):
Bembrops gobioides
(Goode, 1880);
Centropristis philadelphica
(Linnaeus, 1758);
Chauliodus sloani
Bloch et Schneider, 1801;
Chlorophthalmus agassizi
Bonaparte, 1840;
Chloroscombrus chrysurus
(Linnaeus, 1766);
Citharichthys spilopterus
Günther, 1862;
Coelorinchus caelorhincus
(Risso, 1810);
Cyclopsetta chittendeni
Bean, 1895;
Cyclothone alba
Brauer, 1906;
Cyclothone braueri
Jespersen et Tåning, 1926;
Cyclothone pseudopallida
Mukhacheva, 1964;
Dibranchus atlanticus
Peters, 1876;
Epigonus pandionis
(Goode et Bean, 1881);
Fowlerichthys radiosus
(Garman, 1896);
Laemonema goodebeanorum
Meléndez et Markle, 1997;
Lagocephalus laevigatus
(Linnaeus, 1766);
Lepophidium brevibarbe
(Cuvier, 1829);
Lutjanus campechanus
(Poey, 1860);
Malacocephalus occidentalis
Goode et Bean, 1885;
Merluccius albidus
(Mitchill, 1818);
Micropogonias furnieri
(Desmarest, 1823);
Monolene sessilicauda
Goode, 1880;
Ogcocephalus declivirostris
Bradbury, 1980;
Peristedion greyae
Miller, 1967;
Porichthys plectrodon
Jordan et Gilbert, 1882;
Prionotus longispinosus
Teague, 1951;
Prionotus paralatus
Ginsburg, 1950;
Pristipomoides aquilonaris
(Goode et Bean, 1896);
Rhynchoconger flavus
(Goode et Bean, 1896);
Sardinella aurita
Valenciennes, 1847;
Saurida brasiliensis
Norman, 1935;
Sternoptyx diaphana
Hermann, 1781;
Symphurus diomedeanus
(Goode et Bean, 1885);
Synagrops bellus
(Goode et Bean, 1896);
Trachurus lathami
Nichols, 1920;
Trichiurus lepturus
Linnaeus, 1758;
Trichopsetta ventralis
(Goode et Bean, 1885);
Urophycis cirrata
(Goode et Bean, 1896);
Zalieutes mcgintyi
(Fowler, 1952). The fish species studied represented 28 families (in alphabetical order): Antennariidae, Batrachoididae, Bembropidae, Bothidae, Carangidae, Chlorophthalmidae, Congridae, Cyclopsettidae, Cynoglossidae, Dorosomatidae, Epigonidae, Gonostomatidae, Lutjanidae, Macrouridae, Merlucciidae, Moridae, Ogcocephalidae, Ophidiidae, Phycidae, Sciaenidae, Serranidae, Sternoptychidae, Stomiidae, Synagropidae, Synodontidae, TetraodontidaeTrichiuridae, Triglidae. A new maximum standard length (SL) was recorded for
Cyclothone alba
,
C. braueri
,
C. pseudopallida
, and
Lepophidium brevibarbe
. A positive allometric growth was reported in nine species, negative allometric growth in 16 species, and isometric growth in 14 species.
This study was undertaken to evaluate the association between components defining insulin resistance and breast cancer in women.
We conducted a systematic review of four databases (PubMed-Medline, ...EMBASE, Web of Science, and Scopus) for observational studies evaluating components defining insulin resistance in women with and without breast cancer. A meta-analysis of the association between insulin resistance components and breast cancer was performed using random effects models.
Twenty-two studies (n = 33,405) were selected. Fasting insulin levels were not different between women with and without breast cancer (standardized mean difference, SMD -0.03, 95%CI -0.32 to 0.27; p = 0.9). Similarly, non-fasting/fasting C-peptide levels were not different between the two groups (mean difference, MD 0.07, -0.21 to 0.34; p = 0.6). Using individual odds ratios (ORs) adjusted at least for age, there was no higher risk of breast cancer when upper quartiles were compared with the lowest quartile (Q1) of fasting insulin levels (OR Q2 vs. Q1 0.96, 0.71 to 1.28; OR Q3 vs. Q1 1.22, 0.91 to 1.64; OR Q4 vs. Q1 0.98, 0.70 to 1.38). Likewise, there were no differences for quartiles of non-fasting/fasting C-peptide levels (OR Q2 vs. Q1 1.12, 0.91 to 1.37; OR Q3 vs. Q1 1.20, 0.91 to 1.59; OR Q4 vs. Q1 1.40, 1.03 to 1.92). Homeostatic model assessment (HOMA-IR) levels in breast cancer patients were significantly higher than in people without breast cancer (MD 0.22, 0.13 to 0.31, p<0.00001).
Higher levels of fasting insulin or non-fasting/fasting C-peptide are not associated with breast cancer in women. HOMA-IR levels are slightly higher in women with breast cancer.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Evidence increasingly suggests that neural structures that respond to primary and secondary rewards are also implicated in the processing of social rewards. The 'Like'-a popular feature on social ...media-shares features with both monetary and social rewards as a means of feedback that shapes reinforcement learning. Despite the ubiquity of the Like, little is known about the neural correlates of providing this feedback to others. In this study, we mapped the neural correlates of providing Likes to others on social media. Fifty-eight adolescents and young adults completed a task in the MRI scanner designed to mimic the social photo-sharing app Instagram. We examined neural responses when participants provided positive feedback to others. The experience of providing Likes to others on social media related to activation in brain circuity implicated in reward, including the striatum and ventral tegmental area, regions also implicated in the experience of receiving Likes from others. Providing Likes was also associated with activation in brain regions involved in salience processing and executive function. We discuss the implications of these findings for our understanding of the neural processing of social rewards, as well as the neural processes underlying social media use.
IMPORTANCE: More than half of youth with autism spectrum disorders (ASDs) have sensory overresponsivity (SOR), an extreme negative reaction to sensory stimuli. However, little is known about the ...neurobiological basis of SOR, and there are few effective treatments. Understanding whether SOR is due to an initial heightened sensory response or to deficits in regulating emotional reactions to stimuli has important implications for intervention. OBJECTIVE: To determine differences in brain responses, habituation, and connectivity during exposure to mildly aversive sensory stimuli in youth with ASDs and SOR compared with youth with ASDs without SOR and compared with typically developing control subjects. DESIGN, SETTING, AND PARTICIPANTS: Functional magnetic resonance imaging was used to examine brain responses and habituation to mildly aversive auditory and tactile stimuli in 19 high-functioning youths with ASDs and 19 age- and IQ-matched, typically developing youths (age range, 9-17 years). Brain activity was related to parents’ ratings of children’s SOR symptoms. Functional connectivity between the amygdala and orbitofrontal cortex was compared between ASDs subgroups with and without SOR and typically developing controls without SOR. The study dates were March 2012 through February 2014. MAIN OUTCOMES AND MEASURES: Relative increases in blood oxygen level–dependent signal response across the whole brain and within the amygdala during exposure to sensory stimuli compared with fixation, as well as correlation between blood oxygen level–dependent signal change in the amygdala and orbitofrontal cortex. RESULTS: The mean age in both groups was 14 years and the majority in both groups (16 of 19 each) were male. Compared with neurotypical control participants, participants with ASDs displayed stronger activation in primary sensory cortices and the amygdala (P < .05, corrected). This activity was positively correlated with SOR symptoms after controlling for anxiety. The ASDs with SOR subgroup had decreased neural habituation to stimuli in sensory cortices and the amygdala compared with groups without SOR. Youth with ASDs without SOR showed a pattern of amygdala downregulation, with negative connectivity between the amygdala and orbitofrontal cortex (thresholded at z > 1.70, P < .05). CONCLUSIONS AND RELEVANCE: Results demonstrate that youth with ASDs and SOR show sensorilimbic hyperresponsivity to mildly aversive tactile and auditory stimuli, particularly to multiple modalities presented simultaneously, and show that this hyperresponsivity is due to failure to habituate. In addition, findings suggest that a subset of youth with ASDs can regulate their responses through prefrontal downregulation of amygdala activity. Implications for intervention include minimizing exposure to multiple sensory modalities and building coping strategies for regulating emotional response to stimuli.
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