Cotadutide (GLP-1/Glucagon dual receptor agonist) modulates hypothalamic orexigenic and anorexigenic neuropeptides in obese mice.

The hypothalamic neuropeptides linked to appetite and satiety were investigated in obese mice treated with cotadutide (a dual receptor agonist of glucagon-like peptide 1 (GLP-1R)/Glucagon (GCGR)). Twelve-week-old male C57BL/6 mice were fed a control diet (C group, n = 20) or a high-fat diet (HF group, n = 20) for ten weeks. Each group was further divided, adding cotadutide treatment and forming groups C, CC, HF, and HFC for four additional weeks. The hypothalamic arcuate neurons were labeled by immunofluorescence, and protein expressions (Western blotting) for neuropeptide Y (NPY), proopiomelanocortin (POMC), agouti-related protein (AgRP), and cocaine- and amphetamine-regulated transcript (CART). Cotadutide enhanced POMC and CART neuropeptides and depressed NPY and AGRP neuropeptides. In addition, gene expressions (RT-qPCR) determined that Lepr (leptin receptor) and Calcr (calcitonin receptor) were diminished in HF compared to C but enhanced in CC compared to C and HFC compared to HF. Besides, Socs3 (suppressor of cytokine signaling 3) was decreased in HFC compared to HF, while Sst (somatostatin) was higher in HFC compared to HF; Tac1 (tachykinin 1) and Mc4r (melanocortin-4-receptor) were lower in HF compared to C but increased in HFC compared to HF. Also, Glp1r and Gcgr were higher in HFC compared to HF. In conclusion, the findings are compelling, demonstrating the effects of cotadutide on hypothalamic neuropeptides and hormone receptors of obese mice. Cotadutide modulates energy balance through the gut-brain axis and its associated signaling pathways. The study provides insights into the mechanisms underlying cotadutide's anti-obesity effects and its possible implications for obesity treatment.

Fasting Modulates GABAergic Synaptic Transmission to Arcuate Kisspeptin Neurons in Female Mice.

It is well-established that the hypothalamic-pituitary-gonadal (HPG) axis is suppressed due to negative energy balance. However, less information is available on whether kisspeptin neuronal activity contributes to fasting-induced responses. In the present study, female and male mice were fasted for 24 hours or provided food ad libitum (fed group) to determine whether acute fasting is sufficient to modulate kisspeptin neuronal activity. In female mice, fasting attenuated luteinizing hormone (LH) and prolactin (PRL) serum levels and increased follicle-stimulating hormone levels compared with the fed group. In contrast, fasting did not affect gonadotropin or PRL secretion in male mice. By measuring genes related to LH pulse generation in micropunches obtained from the arcuate nucleus of the hypothalamus (ARH), we observed that fasting reduced Kiss1 mRNA levels in female and male mice. In contrast, Pdyn expression was upregulated only in fasted female mice, whereas no changes in the Tac2 mRNA levels were observed in both sexes. Interestingly, the frequency and amplitude of the GABAergic postsynaptic currents recorded from ARH kisspeptin neurons (ARHKisspeptin) were reduced in 24-hour fasted female mice but not in males. Additionally, neuropeptide Y induced a hyperpolarization in the resting membrane potential of ARHKisspeptin neurons of fed female mice but not in males. Thus, the response of ARHKisspeptin neurons to fasting is sexually dependent with a female bias, associated with changes in gonadotropins and PRL secretion. Our findings suggest that GABAergic transmission to ARHKisspeptin neurons modulates the activity of the HPG axis during situations of negative energy balance.

Adipose Tissue Denervation Blunted the Decrease in Bone Formation Promoted by Obesity in Rats.

The impact of obesity upon bone metabolism is controversial since both beneficial or harmful effects have been reported. Bone remodeling is modulated by the central nervous system through cytokines, hormones and neuromodulators. The present study aimed to evaluate the effects evoked by bilateral retroperitoneal white adipose tissue (rWAT) denervation (Dnx) upon bone mineral metabolism and remodeling in an experimental model of obesity in rats. Male Wistar rats were fed during 18 weeks with high-fat diet (HFD) or standard diet (SD) as controls, and rWAT Dnx or Sham surgery was performed at the 14th week. Biochemical and hormonal parameters, bone histomorphometry, rWAT and hypothalamus protein and gene expression were analyzed. The HFD group presented decreased bone formation parameters, increased serum and bone leptin and FGF23, increased serum and hypothalamic neuropeptide Y (NPY) and decreased serum 1,25-dihydroxyvitamin D3 and PTH. After rWAT Dnx, bone markers and histomorphometry showed restoration of bone formation, and serum and hypothalamic NPY decreased, without alteration in leptin levels. The present study shows that the denervation of rWAT improved bone formation in obese rats mediated by a preferential reduction in neurohormonal actions of NPY, emphasizing the relevance of the adipose tissue-brain-bone axis in the control of bone metabolism in obesity.

Levetiracetam plus Oxcarbazepine Combination Treatment Downregulates Serum Multidrug Resistance Protein 1 Levels and Upregulates Neuropeptide Y Levels in Children with Epilepsy

Abstract The aim of the present study was to investigate the usefulness of multidrug resistance protein 1 (MDR1) and neuropeptide Y (NPY) levels in predicting the efficacy of levetiracetam (LEV) plus oxcarbazepine (OXC) treatment administered to children with epilepsy and to determine their prognosis. Overall, 193 children with epilepsy admitted to the hospital were enrolled and randomly divided into two groups according to different treatment methods: group A (n = 106, treated with LEV plus OXC combination) and group B (n = 87, treated with OXC only). After treatment, compared with group B, group A exhibited a remarkably higher total effective rate and a significantly lower total adverse reaction rate. Areas under the curve for MDR1 and NPY for predicting ineffective treatment were 0.867 and 0.834, whereas those for predicting epilepsy recurrence were 0.916 and 0.829, respectively. Electroencephalography abnormalities, intracranial hemorrhage, neonatal convulsion, premature delivery, and MDR1 and NPY levels were independent risk factors for poor prognosis in children with epilepsy. Serum MDR1 and NPY levels exhibited a high predictive value for early epilepsy diagnosis, treatment efficacy assessment, and prognostication in children with epilepsy treated with LEV plus OXC combination.

Dextrose Prolotherapy for Symptomatic Grade IV Knee Osteoarthritis: A Pilot Study of Early and Longer-Term Analgesia and Pain-Specific Cytokine Concentrations.

Background: Neurocytokines may upregulate or downregulate neuropathic pain. We hypothesized that dextrose (D-glucose) injections for therapeutic purposes (dextrose prolotherapy: DPT) in painful knee osteoarthritis (KOA) would favorably affect synovial-fluid neurocytokine concentrations. Methods: Twenty participants with grade IV symptomatic KOA received synovial-fluid aspiration followed by dextrose or simulated dextrose injections, followed by the reverse after one week. All participants then received open-label dextrose injections monthly for 6 months, with serial assessments of walking pain at 20 min for 9 months, as well as synovial-neurocytokine-concentration measurements (calcitonin gene-related peptide, substance P (SP), and neuropeptide Y (NPY)) at one week and three months. Results: Clinically important analgesia was observed at 20 min and for 9 months post dextrose injection. One -week synovial-fluid SP concentration rose by 111% (p = 0.028 within groups and p = 0.07 between groups) in the dextrose-injected knees compared to synovial-fluid aspiration only. Three-month synovial-fluid NPY concentration dropped substantially (65%; p < 0.001) after open-label dextrose injection in all knees. Conclusions: Prompt and medium-term analgesia after intra-articular dextrose injection in KOA was accompanied by potentially favorable changes in synovial-fluid neurocytokines SP and NPY, respectively, although these changes were isolated. Including neurocytokines in future assessments of DPT to elucidate mechanisms of action is recommended.

Influence of Neuropeptide Y and Neuropeptide Y 2 Receptor Variants in Acute Coronary Syndrome

Abstract Background The neuropeptide Y (NPY) is one of the most abundant neurotransmitters in the nervous system. NPY acts as a potent stimulator of angiogenesis, inflammation, and adipogenesis, through the NPY 2 receptor (NPY2R). Changes in the NPY signaling pathway have been linked to Acute Coronary Syndrome (ACS). Objectives The purpose of this study is to determine the association between variants in the NPY and NPY2R genes, as well as the severity of acute coronary syndrome (ACS). Methods Approximately 221 ACS patients and 278 healthy controls were selected for this study. Four variants in NPY and two variants in NPY2R genes were genotyped using Taqman allelic discrimination and sequencing. The Chi-square and Fisher's exact tests were used to verify the genotype frequencies. The logistic regression analyses were used for the evaluation of the studied variables. Haplotype analysis was used to evaluate the linkage disequilibrium (LD) between the variants (p<0.05). Results An association of NPY c.20T>C variant was found with the ACS group when compared to the healthy group. In the analysis between variants and risk factors in the ACS group, NPY c.84G>A was associated with hypertension. The analysis between TIMI risk showed a significance for NPY c.20T>C between the low and intermediate/high TIMI risk groups. In the haplotype analysis, strong linkage disequilibrium (LD) was found between the variants NPY c.150G>A and NPY c.-485T>C. Conclusion The NPY c.20T>C variant appears to contribute to the development of ACS. The NPY2R c.-1116A>G variant may contribute to the early development of ACS and the NPY c.84G>A variant appears to contribute to the development of hypertension. In addition, the NPY c.20T>C is associated with a protective effect in ACS severity.

Effects of prenatal exposure to fluoxetine on circadian rhythmicity in the locomotor activity and neuropeptide Y and 5-HT expression in male and female adult Wistar rats.

Serotonin (5-HT) reuptake inhibitors, such as fluoxetine, are the most prescribed antidepressant for maternal depression. In this sense, it exposes mothers and the brains of infants to increased modulatory and trophic effects of serotonergic neurotransmission. 5-HT promotes essential brain changes throughout its development, which include neuron migration, differentiation and organisation of neural circuitries related to emotional, cognitive and circadian behavior. Early exposure to the SSRIs induces long-term effects on behavioral and neural serotonergic signalisation. We have aimed to evaluate the circadian rhythm of locomotor activity and the neurochemical content, neuropeptide Y (NPY) and 5-HT in three brain areas: intergeniculate leaflet (IGL), suprachiasmatic nuclei (SCN) and raphe nuclei (RN), at two zeitgebers (ZT6 and ZT18), in male and female rat's offspring early exposed (developmental period GD13-GD21) to fluoxetine (20 mg/kg). First, we have conducted daily records of the locomotor activity rhythm using activity sensors coupled to individual cages over 4 weeks. We have lastly evaluated the immunoreactivity of NPY in both SCN and IGL, as well the 5-HT expression in the dorsal and medial RN. In summary, our results showed that (1) prenatal fluoxetine affects phase entrainment of the rest/activity rhythm at ZT6 and ZT18, more in male than female specimens, and (2) modulates the NPY and 5-HT expression. Here, we show male rats are more susceptible to phase entrainment and the NPY and 5-HT misexpression compared to female ones. The sex differences induced by early exposure to fluoxetine in both the circadian rhythm of locomotor activity and the neurochemical expression into SCN, IGL and midbrain raphe are an important highlight in the present work. Thus, our results may help to improve the knowledge on neurobiological mechanisms of circadian rhythms and are relevant to understanding the "broken brains" and behavioral abnormalities of offspring early exposed to antidepressants.

Restraint stress potentiates neuropeptide Y-mediated impairment on spatial memory in rats.

Memory is the ability to store, retrieve and use information that requires a progressive time-dependent stabilization process known as consolidation to be established. The hippocampus is essential for processing all the information that forms memory, especially spatial memory. Neuropeptide Y (NPY) affects memory, so in this study we investigated the participation and recruitment of NPY receptors during spatial memory consolidation in rats. Using the water maze test, we show that NPY (1 pmol) injected into the dorsal hippocampus impaired memory consolidation and that previous restraint stress (30 min) potentiates NPY effects, i.e. further impaired memory consolidation. Using selective antagonists for NPY Y1 and Y2 receptors we demonstrate that both receptors play a key role on spatial memory consolidation. Our data suggest that NPY modulates aversive and adaptive memory formation by NPY receptors activation.

Effects of Dietary Calcium Propionate Supplementation on Hypothalamic Neuropeptide Messenger RNA Expression and Growth Performance in Finishing Rambouillet Lambs.

The objective of this experiment was to evaluate the effects of feeding different levels concentrations of dietary calcium propionate (CaPr) on lambs' growth performance; ruminal fermentation parameters; glucose-insulin concentration; and hypothalamic mRNA expression for neuropeptide Y (NPY), agouti-related peptide (AgRP), and proopiomelanocortin (POMC). Thirty-two individually fed lambs were randomly assigned to four treatments: (1) control diet (0 g/kg of CaPr), (2) low CaPr, (30 g/kg dry matter (DM)), (3) medium CaPr, (35 g/kg DM), and (4) high CaPr (40 g/kg DM). After 42 days of feeding, lambs were slaughtered for collecting samples of the hypothalamus. Data were analyzed as a complete randomized design, and means were separated using linear and quadratic polynomial contrast. Growth performance was not affected (p ≥ 0.11) by dietary CaPr inclusion. The ruminal concentration of total volatile fatty acids (VFA) increased linearly (p = 0.04) as dietary CaPr increased. Likewise, a linear increase in plasma insulin concentration (p = 0.03) as dietary CaPr concentration increased. The relative mRNA expression of NPY exhibited a quadratic effect (p < 0.01), but there were significant differences in the mRNA expression of AgRP and POMC (p ≥ 0.10). Dietary calcium propionate did not improve lamb growth performance in lambs feed with only forage diets. Intake was not correlated with feed intake with mRNA expression of neuropeptides.

Anxious Profile Influences Behavioral and Immunohistological Findings in the Pilocarpine Model of Epilepsy.

Anxiety and epilepsy have a complex bidirectional relationship, where a depressive/anxious condition is a factor that can trigger seizures which in turn can aggravate the depressive/anxious condition. In addition, brain structures such as the hippocampus and amygdala might have a critical relevance in both epilepsy and anxiety. The aim of the present work was to investigate the influence of different anxious profiles to epileptogenesis. Initially, animals were screened through the elevated plus-maze anxiety test, and then seizure development was evaluated using the pilocarpine model of epilepsy. There were no differences in the susceptibility to status epilepticus, mortality rate or frequency of spontaneous recurrent seizures between animals characterized as anxious as compared to the non-anxious animals. Next, we evaluated immunohistological patterns related to seizures and anxiety in various related brain areas. Despite a decrease in the density of neuropeptide Y and parvalbumin expression in epileptic animals, those presenting greater neuropeptide Y immunoreactivity in various brain regions, also showed higher spontaneous recurrent seizures frequency. Differences on the anxious profile showed to interfere with some of these findings in some regions. In addition, animals that were injected with pilocarpine, but did not develop status epilepticus, had behavioral and neuroanatomical alterations as compared to control animals, indicating its importance as an additional tool for investigating the heterogeneity of the epileptogenic response after an initial insult. This study allowed to better understand the association between anxiety and temporal lobe epilepsy and might allow for therapeutic targets to be developed to minimize the negative impacts associated with it.

Development and characterization of two novel 68 Ga-labelled neuropeptide Y short analogues with potential application in breast cancer imaging.

In vivo receptor targeting with radiolabelled peptide-based probes is an attractive approach for the development of novel radiotracers for molecular imaging. This work presents the development and characterization of two novel neuropeptide Y analogues labelled with a positron emitter 68 Ga, for potential use in breast cancer imaging. Both analogues share the same amino acid sequence and were derivatized with NOTA through either a lysine linker (L1) or an acetylated lysine (L2). In both cases, a single product with radiochemical purity higher than 95% was obtained. The two complexes were hydrophilic, showed remarkable in vitro stability, good cellular uptake, binding affinity in the nanomolar range and high cellular internalization rate. Biodistribution studies revealed low blood uptake and elimination through the urinary tract. The addition of an acetyl group in the spacer increased the lipophilicity of C2 and modified the reactivity of the ε-amino group of the lysine which resulted in lower protein binding and lower percentage of injected dose in bladder and urine. The tumour versus muscle ratio was (3.8 ± 0.4) for 68 Ga-L1 and (4.7 ± 0.4) for 68 Ga-L2. These results encourage performing further studies in order to complete the evaluation of both tracers as potential radiopharmaceutical for breast cancer imaging.

Validation in a Brazilian population of gene markers of periodontitis previously investigated by GWAS and bioinformatic studies.

BACKGROUND: Bioinformatic tools and genome-wide association studies (GWAS) have led to comprehensive identification of single nucleotide polymorphisms (SNPs) associated with periodontitis in diverse populations. Here we aimed to detect and validate the association of seven SNPs as genetic markers of susceptibility to periodontitis in a Brazilian population. METHODS: This case-control study assessed complete periodontal parameters of 714 subjects with periodontal status classified as healthy/mild periodontitis (n = 356) and moderate/severe periodontitis (n = 358). Genotyping for rs187238, rs352140, rs1360573, rs2521634, rs3811046, rs3826782, and rs7762544 SNPs were evaluated. Genetic-phenotype associations, and sex or smoking effects of SNPs on periodontitis were tested using multiple logistic regressions adjusted for covariates. RESULTS: The rs2521634-AA (close to NPY gene) presented increased risk for severe periodontitis (OR = 2.34; 95% CI = 1.19-4.59). The rs3811046-GG (IL37 gene) demonstrated increased risk for moderate periodontitis (OR = 2.58; 95% CI = 1.28-5.18). Higher risk for moderate periodontitis was found in male with rs7762544-AG close to NCR2 gene. The rs352140-TT in the TLR9 gene proved to be associated with lower risk to severe periodontitis in men. The rs2521634-AA was associated with higher percentage of interproximal probing pocket depth (P = .004). CONCLUSIONS: This is the first evidence of validation in a Brazilian population of genetic markers of periodontitis previously investigated by GWAS and bioinformatics studies. SNPs in the NPY, IL37, and NCR2 genes were associated with susceptibility to moderate or severe periodontitis; whereas the TLR9 marker was associated with lower chance to develop severe periodontitis. Those SNPs had sex- and smoking-habit-specific effects on periodontitis; reinforcing the genetic profile predisposing to periodontitis.

Effects of Y1 receptor agonist on the pancreatic islet of diet-induced obese and diabetic mice.

AIMS: Agonists of the NPY receptor might be potential in protecting pancreatic islets from injury. We aimed to characterize the role of [Leu31, Pro34]-PYY, an NPYR1 agonist, in pancreatic islets of a diet-induced obesity and insulin resistance model. METHODS: We studied long-term high-fat diet intake as a model and selective agonist of the Y1 receptor to explore the pancreatic islet architecture and stereology, and insulin secretion in isolated islets and a whole animal model. Gene and protein expressions were assessed in isolated islets investigating the signaling cascades involved in inflammation, insulin signaling, and secretion. Also, the insulin release potential was studied in vitro. RESULTS: Our data reveal that an infusion of NPYR1 for 14 days did not change the body mass of mice and eating behavior. NPYR1 did not modify the islet and beta-cell mass but positively impacted the inflammatory process by lowering the expressions of Tnf alpha and If gamma. Besides, NPYR1 restored the insulin signaling and the exocytose pattern by activating the PDX1/STAT3 pathway and improving the leptin signaling cascade. CONCLUSIONS: The findings are compellingly indicating the potential effect of the NPYR1 as a target for improving the insulin resistance condition. As such, the infusion of the NPYR1 agonist would help to enhance insulin secretion by the beta-cell from the PDX1/STAT3 pathway and the improvement of the inflammatory process.

Intermittent fasting, adipokines, insulin sensitivity, and hypothalamic neuropeptides in a dietary overload with high-fat or high-fructose diet in mice.

The intermittent fasting (IF) might have benefits on metabolism and food intake. Twelve-week old C57BL/6 J mice were fed a control diet (C, 10% kcal fat), a high-fat diet (HF, 50% kcal fat) or a high-fructose diet (HFru, 50% kcal fructose) for 8 weeks, then half of the animals in each group underwent IF (24 h fed, 24 h fasting) for an additional 4 weeks. Although food intake on the fed day remained the same for all groups, all fasting groups showed a reduction in body mass compared to their counterparts. IF reduced total cholesterol, triacylglycerol, fasting glucose, fasting insulin resistance index, and plasma leptin, but increased plasma adiponectin. IF reduced Leptin gene expression in the HF-IF group, but increased proinflammatory markers in the hypothalamus, also in the C-IF group. Both groups HFru-IF and C-IF, showed alterations in the leptin signaling pathway (Leptin, OBRb, and SOCS3), mainly in the HFru-IF group, suggesting leptin resistance. NPY and POMC neuropeptides labeled the neurons of the hypothalamus by immunofluorescence, corroborating qualitatively other quantitative findings of the study. In conclusion, current results are convincing in demonstrating the IF effect on central regulation of food intake control, as shown by NPY and POMC neuropeptide expressions, resulting in a lower weight gain. Besides, IF improves glycemia, lipid metabolism, and consequently insulin and leptin resistance. However, there is increased expression of inflammatory markers in mouse hypothalamus challenged by the HF and HFru diets, which in the long term may induce adverse effects.

Modulation of neuropeptide Y levels is impaired in crack withdrawal patients

Abstract Introduction The dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has a key role in drug addiction susceptibility. In addition to the well-known relationship between cortisol and the HPA axis, other molecules are involved with stress response and could modify the HPA activation, such as the neuropeptide Y (NPY), which has anxiolytic proprieties. There are few studies evaluating the effect of NPY levels on addiction, especially in crack cocaine dependence. Objective To evaluate NPY in crack users during early withdrawal to determine its relationship with drug use and cortisol levels. Methods We analyzed 25 male inpatient crack users. Serum NPY levels were measured at admission and discharge (mean of 24 days). Morning salivary cortisol was measured at admission. Results Serum NPY levels at admission and discharge were very similar. Lower NPY levels at discharge were associated with higher lifetime crack use. Also, a negative correlation was found between morning cortisol and delta NPY (NPY discharge - NPY admission). Conclusion These preliminary findings indicate that crack use influences the modulation of NPY levels and modifies stress response. The NPY pathway may play an important role in the pathophysiology of crack addiction, and the anxiolytic effect of NPY may be impaired in crack users. Future studies should consider NPY as a measurable indicator of the biological state in addiction.

Intra-articular injection of 2-pyridylethylamine produces spinal NPY-mediated antinociception in the formalin-induced rat knee-joint pain model.

Low doses of histamine or H1R agonist 2-pyridylethylamine (2-PEA) into the knee-joint were found to decrease formalin-induced articular nociception in rats. In this study, we evaluated the participation of spinal NPY in the antinociceptive effect produced by 2-PEA. Injection of formalin (1.5%) into one of the knee-joints causes the limping of the respective limb due to nociception, which was registered each 5 min over 60 min. Neuropeptide Y1 receptor (Y1R) content in the spinal cord was evaluated by western-blotting. Intrathecal (i.t.) injection of Y1R agonist Leu31, Pro34-NPY (0.7-7 µmol) decreased nociception, while injection of the antagonist BIBO 3304 (4 µmol), increased nociception. Antinociception produced by 2-PEA was reversed by a sub-effective i.t. dose of the Y1R antagonist. Similarly, this antinociceptive effect was prevented by i.t. pretreatment with the neurotoxin NPY-saporin (750 ng), which also reduced immunoblotting for Y1R in spinal cord homogenates. These data support the idea that antinociception induced by H1R agonists in the knee-joint of rats may be mediated by the spinal release of NPY, and this peptide seems to be acting via Y1R.

Development and characterization of a 99m Tc-labeled Neuropeptide Y short analog with potential application in breast cancer imaging.

The aim of this work was to develop and evaluate a 99m Tc-labeled neuropeptide Y derivative with affinity toward Y1-receptor. The selected amino acid sequence included nine amino acids derived from the C-terminal portion of the NPY complemented with the addition of one cysteine-mercaptoacetic acid moiety to bind the radiometal. Labeling was achieved through the preparation of a 3 + 1 nitrido complex. Physicochemical evaluation, cell uptake, internalization and externalization studies, and competitive assays were performed. Biodistribution experiments were carried out in normal and tumor-bearing mice. A single product with radiochemical purity >90% and high stability was obtained. In vitro analysis showed specific cellular uptake, IC50 of 73.2 nM, and a high internalization rate (80%). Biodistribution studies showed low blood and renal uptake and combined hepatobiliary and urinary elimination. Preliminary studies in mice bearing induced breast tumors rendered promising uptake values.

Relations of neuropeptide Y and heme oxygenase-1 expressions with fetal brain injury in rats with intrahepatic cholestasis of pregnancy

Purpose: To investigate the relations of neuropeptide Y (NPY) and heme oxygenase-1 (HO-1) expressions with fetal brain injury in rats with intrahepatic cholestasis of pregnancy (ICP). Methods: Sixty rats pregnant for 15 days were randomly divided into experimental and control groups. The ICP model was established in experimental group. On the 21st day, the blood biochemical test, histopathological examination of pregnant rat liver and fetal brain tissues and immunohistochemical analysis of fetal rat brain tissues were performed. Results: On the 21st day, the alanineaminotransferase, aspartate aminotransferase and total bile acid levels in experimental group were significantly higher than control group (P<0.01). Compared with control group, there was obvious vacuolar degeneration in pregnant rat liver tissue and fetal brain tissue in experimental group. NPY expression in fetal brain tissue was negative in control group and positive in experimental group. HO-1 expression in fetal brain tissue was strongly positive in control group and positive in experimental group. There was significant difference of immunohistochemical staining optical density between two groups (P<0.01). Conclusion: In fetal brain of ICP rats, the NPY expression is increased, and the HO-1 expression is decreased, which may be related to the fetal brain injury.(AU)

Cyclohexane Inhalation Produces Long-Lasting Alterations in the Hippocampal Integrity and Reward-Seeking Behavior in the Adult Mouse.

Cyclohexane (CHX) is an organic solvent commonly used as a drug-of-abuse. This drug increases the oxidative stress and glial reactivity in the hippocampus, which suggests that this brain region is vulnerable to CHX effects. This study aimed to establish the behavioral changes and the pathological alterations that occur in the Cornu Ammonis 3 (CA3) and Dentate Gyrus (DG) after a long-lasting exposure to CHX. We exposed CD1 mice to a recreational-like dose of CHX (~ 30,000 ppm) for 30 days and explored its consequences in motor skills, reward-seeking behavior, and the CA3 and DG hippocampal subfields. Twenty-four hours after the last administration of CHX, we found a significant decrease in the number of c-Fos+ cells in the hippocampal CA3 and DG regions. This event coincided with an increased in NMDAR1 expression and apoptotic cells in the CA3 region. At day 13th without CHX, we found a persistent reduction in the number of c-Fos+ and TUNEL+ cells in DG. At both time points, the CHX-exposed mice showed a strong overexpression of neuropeptide Y (NPY) in the CA3 stratum lucidum and the hippocampal hilus. In parallel, we used an operant-based task to assess motor performance and operant conditioning learning. The behavioral analysis indicated that CHX did not modify the acquisition of operant conditioning tasks, but affected some motor skills and increased the reward-seeking behavior. Altogether, this evidence reveals that CHX exposure provokes long-lasting changes in the hippocampal subfields, induces motor impairments and increases the motivation-guided behavior. These findings can help understand the deleterious effect of CHX into the adult hippocampus and unveil its potential to trigger addiction-like behaviors.