Role of nesfatin-1 in anxiety, depression and the response to stress

Spexin and nesfatin-1-expressing neurons in the male human claustrum

Neuropeptides are involved in numerous brain activities being responsible for a wide spectrum of higher mental functions. The purpose of this concise, structural and qualitative investigation was to map the possible immunoreactivity of the novel regulatory peptides: spexin (SPX) and nesfatin-1 within the human claustrum. SPX is a newly identified peptide, a natural ligand for the galanin receptors (GALR) 2/3, with no molecular structure similarities to currently known regulatory factors. SPX seems to have multiple physiological functions, with an involvement in reproduction and food-intake regulation recently revealed in animal studies. Nesfatin-1, a second pleiotropic neuropeptide, which is a derivative of the nucleobindin-2 (NUCB-2) protein, is characterized by a wide distribution in the brain. Nesfatin-1 is a substance with a strong anorexigenic effect, playing an important role in the neuronal circuits of the hypothalamus that regulate food intake and energy homeostasis. On the other hand, nesfatin-1 may be involved in several important brain functions such as sleep, reproductive behaviour, cognitive processes, stress responses and anxiety. For the first time we detected and described a population of nesfatin-1 and SPX expressing neurons in the human claustrum using immunohistochemical and fluorescent methods. The study presents the novel identification of SPX and nesfatin-1 immunopositive neurons in the human claustrum and their assemblies show similar patterns of distribution in the whole structure.

Suppressive action of nesfatin-1 and nesfatin-1-like peptide on cortisol synthesis in human adrenal cortex cells

Nucleobindin-derived peptides, nesfatin-1 [NESF-1] and nesfatin-1-like-peptide [NLP] have diverse roles in endocrine and metabolic regulation. While both peptides showed a stimulatory effect on the synthesis of proopiomelanocortin (POMC), the adrenocorticotropic hormone (ACTH) precursor in mouse corticotrophs, whether NESF-1 and NLP have any direct effect on glucocorticoid [GC] synthesis in the adrenal cortex remains unknown. The main aim of this study was to determine if NESF-1 and/or NLP act directly on adrenal cortex cells to regulate cortisol synthesis in vitro. Whether NLP injection affects stress-hormone gene expression in the adrenal gland and pituitary in vivo in mice was also assessed. In addition, cortisol synthetic pathway in Nucb1 knockout mice was studied. Human adrenal cortical [H295R] cells showed immunoreactivity for both NUCB1/NLP and NUCB2/NESF-1. NLP and NESF-1 decreased the abundance of steroidogenic enzyme mRNAs, and cortisol synthesis and release through the AC/PKA/CREB pathway in H295R cells. Similarly, intraperitoneal injection of NLP in mice decreased the expression of enzymes involved in glucocorticoid (GC) synthesis in the adrenal gland while increasing the expression of Pomc, Pcsk1 and Crhr1 in the pituitary. Moreover, the melanocortin 2 receptor (Mc2r) mRNA level was enhanced in the adrenal gland samples of NLP injected mice. However, the global genetic disruption in Nucb1 did not affect most steroidogenic enzyme mRNAs, and Pomc, Pcsk2 and Crhr1 mRNAs in mice adrenal gland and pituitary gland, respectively. Collectively, these data provide the first evidence for a direct inhibition of cortisol synthesis and secretion by NLP and NESF-1. NUCB peptides might still elicit a net stimulatory effect on GC synthesis and secretion through their positive effects on ACTH-MC2R pathway in the pituitary.

The Relation between Plasma Nesfatin-1 Levels and Aggressive Behavior in Pit Bull Dogs

Aggression is a prevalent and concerning behavioral issue in dogs. Pit Bull dogs, known for their high levels of aggression, are recognized as a focus of concern in society. In our study, we aimed to investigate the behavioral characteristics of Pit Bull dogs and explore the potential roles of peptides involved in the neurobiology of aggression. Initially, female, and male dogs underwent aggression tests, and their aggression levels were categorized. Plasma nesfatin-1, serotonin, oxytocin, and dopamine levels were quantified using ELISA, with blood samples collected after a 24 h fasting period and 2 h post-refeeding. Our findings indicate that aggression in Pit Bull dogs correlates with decreased plasma nesfatin-1, serotonin, and oxytocin levels, while dopamine levels increase. The study's findings indicate that fasted dogs exhibited lower plasma levels of nesfatin-1, serotonin, and dopamine, while plasma oxytocin levels were higher. Furthermore, while the research findings do not suggest a significant relationship between the severity of aggression and the gender of the dog, male Pit Bull breeds appear to have higher plasma nesfatin-1 and serotonin levels compared to their female counterparts. The study's findings demonstrate that nesfatin-1, serotonin, oxytocin, and dopamine play pivotal roles in Pit Bull dogs' aggression, indicating potential interactions among these neuropeptides at the central nervous system level.

Immunohistochemical determination of the excitatory and inhibitory axonal endings contacting NUCB2/nesfatin-1 neurons

Nesfatin-1 is an anorexigenic peptide suppressing food intake and is synthesized and secreted by neurons located in the hypothalamus. Our study was aimed to demonstrate the effect of excitatory and inhibitory neurotransmitters on NUCB2/nesfatin-1 neurons. In this context, dual peroxidase immunohistochemistry staining was performed using NUCB2/nesfatin-1 primary antibody with each of the primary antibodies of vesicular transporter proteins applied as markers for neurons using glutamate, acetylcholine, and GABA as neurotransmitters. In double labeling applied on floating sections, the NUCB2/nesfatin-1 reaction was determined in brown color with diaminobenzidine, while vesicular carrier proteins were marked in black. Slides were analyzed to determine the ratio of nesfatin-1 neurons in the three hypothalamic nucleus in contact with a relevant vesicular carrier protein. The ratios of NUCB2/nesfatin-1 neurons with the innervation were compared among neurotransmitters. In addition, possible gender differences between males and females were examined. The difference in the number of VGLUT2-contacting NUCB2/nesfatin-1 neurons was significantly higher in males when compared to females. When both genders were compared in different nuclei, it was seen that there was no statistical significance in terms of the percentage of NUCB2/nesfatin-1 neuron apposition with VGLUT3. The statistical evaluation showed that number of NUCB2/nesfatin-1 neurons receiving GABAergic innervation is higher in males when compared to females (*p ≤ 0.05; p = 0.045). When the axonal contact of vesicular neurotransmitter transporter proteins was compared between the neurotransmitters, it was determined that the most prominent innervation is GABAergic. In the supraoptic region, no contacts of VAChT-containing axons were found on NUCB2/nesfatin-1 neurons in both female and male subjects. In conclusion, it is understood that both excitatory and inhibitory neurons can innervate the NUCB2/nesfatin-1 neurons and the glutamatergic system is effective in the excitatory innervation while the GABAergic system plays a role in the inhibitory mechanism.

NUCB2/nesfatin-1 in the acute stress response of obese women with high and low anxiety

NUCB2/nesfatin-1 is an anorexigenic peptide hormone first known for its effects on energy homeostasis. More recently, a growing evidence suggests a role of NUCB2/nesfatin-1 in emotion regulation, particularly in the modulation of anxiety, depression and emotional stress response. Since stress-related mood disorders are often comorbid with obesity, we investigated the effect of acute psychosocial stress on circulating NUCB2/nesfatin-1 in obese women and normal-weight controls and its association with symptoms of anxiety. Forty women, 20 obese and 20 normal-weight controls, (aged between 27 and 46 years) were exposed to the Trier Social Stress Test (TSST). We assessed changes of plasma NUCB2/nesfatin-1, salivary cortisol, heart rate and subjective emotional state. Symptoms of anxiety (GAD-7), depressiveness (PHQ-9), perceived stress (PSQ-20), disordered eating (EDE-Q, EDI-2) and health-related quality of life (SF-8) were measured psychometrically. Obese women were further subdivided in a high and low anxiety group. Women with obesity displayed higher psychopathology compared to normal-weight controls. The TSST induced a biological and psychological stress response in both groups (p < 0.001). In normal-weight controls NUCB2/nesfatin-1 increased in response to stress (p = 0.011) and decreased during recovery (p < 0.050), while in obese women only the decrease during recovery was significant (p = 0.002). Obese women with high anxiety displayed higher NUCB2/nesfatin-1 levels than those in the low anxiety group (TSST: +34 %, p = 0.008; control condition: +52 %, p = 0.013). Our data substantiate the involvement of NUCB2/nesfatin-1 in the modulation of stress and anxiety. It remains unclear whether the attenuated stress response in obese subjects is due to metabolic changes or mental comorbidity.

Estradiol and progesterone regulate NUCB2/nesfatin-1 expression and function in GH3 pituitary cells and THESC endometrial cells

Estradiol (E2) and progesterone (P4) are essential sex steroid hormones that play critical roles in the pituitary gland and uterus. Recently, nesfatin-1, a polypeptide hormone that regulates appetite and energy homeostasis in the hypothalamus, was found to be expressed in the pituitary gland and uterus. In this study, we aimed to investigate the relationship between these two steroid hormones and the expression and function of nesfatin-1 in the pituitary gland and uterus using GH3 cells, a lacto-somatotroph cell line, and THESC cells, an endometrial stromal cell line. First, we verified the presence of nesfatin-1 and nesfatin-1 binding sites in GH3 and THESC cells. E2 increased the mRNA expression of NUCB2, the gene encoding the nesfatin-1 protein, in GH3 cells, while P4 had no significant effect. In THESC cells, NUCB2 mRNA expression was decreased by E2 but increased by P4. In addition, nesfatin-1 significantly increased growth hormone (GH) and prolactin (PRL) mRNA expression in GH3 cells, and E2 enhanced this effect. In THESC cells, nesfatin-1 significantly increased the mRNA expression of insulin-like growth factor binding protein 1 (IGFBP1) and PRL, which are decidualization marker genes, and P4 further enhanced this effect. These results suggest that nesfatin-1 may act as a local regulator of GH and PRL production in the pituitary gland and decidualization in the uterus, modulating its effects in response to E2 and P4.

Role of brain NUCB2/nesfatin-1 in stress and stress-related gastrointestinal disorders

Since the discovery of NUCB2/nesfatin-1 as a novel anorexigenic factor, the expanding function of this peptide has been elucidated in recent years. Increasing evidence suggests that NUCB2/nesfatin-1 is also involved in the regulation of stress and stress-related gastrointestinal disorders. Therefore, we investigated the relationship between NUCB2/nesfatin-1, stress and stress-related gastrointestinal disorders and summarized the results of these studies. Different stressors and duration of stress activate different NUCB2/nesfatin-1-associated brain regions and have different effects on serum corticosterone levels. Central and peripheral NUCB2/nesfatin-1 mediates stress-related gastrointestinal disorders but appears to be protective against inflammatory bowel disease. NUCB2/nesfatin-1 plays an important role in mediating the brain-gut crosstalk, but precise clarification is still needed to gain more insight into these complex relationships.

Impact of nonalcoholic fatty liver disease-related metabolic state on depression

Nonalcoholic fatty liver disease (NAFLD), also recently referred as metabolic (dysfunction)-associated fatty liver disease (MAFLD), is characterized by hepatocyte steatosis in the setting of metabolic risk conditions and in the absence of an underlying precursor, for instance alcohol consumption, hepatotropic viruses and hepatotoxic drugs. A possible association between NAFLD and depression has been proposed, owing to intersecting pathophysiological pathways. This narrative review aimed to summarize the current evidence that illustrate the potential pathophysiological and clinical linkage between NAFLD-related metabolic state and depression. Prefrontal cortex lesions are suggested to be a consequence of liver steatosis-associated systematic hyperinflammatory state, a phenomenon also occurring in depression. In addition, depressive symptoms are present in neurotransmitter imbalances. These abnormalities seem to be correlated with NAFLD/MAFLD, in terms of insulin resistance (IR), ammonia and gut dysbiosis' impact on serotonin, dopamine, noradrenaline levels and gamma aminobutyric acid receptors. Furthermore, reduced levels of nesfatin-1 and copine-6-associated BDNF (brain-derived neurotrophic factor) levels have been considered as a probable link between NAFLD and depression. Regarding NAFLD-related gut dysbiosis, it stimulates mediators including lipopolysaccharides, short-chain fatty acids and bile acids, which play significant role in depression. Finally, western diet and IR, which are mainstay components of NAFLD/MAFLD, are, also, substantiated to affect neurotransmitters in hippocampus and produce neurotoxic lipids that contribute to neurologic dysfunction, and thus trigger emotional disturbances, mainly depressive symptoms.

Serum nesfatin-1 level in men with diabetes and erectile dysfunction correlates with generalized anxiety disorder-7: A prospective comparative study

BACKGROUND

Current studies have suggested a close link between nesfatin-1, an appetite-related neuropeptide and gonadal hormones.

OBJECTIVES

We investigated the association between nesfatin-1 serum level and erectile dysfunction severity in men with diabetes as well as the generalized anxiety disorder-7 questionnaire, the patient health questionnaire-9, serum testosterone, kidney and liver functions, glycated haemoglobin and lipid profile.

MATERIALS AND METHODS

Seventy-five participants between 30 and 60 years were enrolled, 25 erectile dysfunction patients with type 2 diabetes (group I), 21 with diabetes and preserved erectile function (group II) and 29 healthy controls (group III). Erectile dysfunction status and severity were determined by the Arabic version of the international index of erectile function-5 for all the participants. Psychological wellbeing was checked by the generalized anxiety disorder-7 questionnaire and the patient health questionnaire-9. Finally, participants were evaluated for serum nesfatin-1, serum testosterone, kidney and liver functions, glycated haemoglobin and lipid profile.

RESULTS

Serum nesfatin-1 levels were significantly lower in groups I and II compared to the controls. The international index of erectile function-5 scores had shown significant correlations with serum nesfatin-1, serum testosterone, generalized anxiety disorder-7, patient health questionnaire-9, diastolic blood pressure, glycated haemoglobin, triglycerides, creatinine and albumin/creatinine ratio. Receiver operating characteristic analysis revealed that serum nesfatin-1 ≥ 0.62 ng/ml, serum testosterone ≥2.9 ng/ml, generalized anxiety disorder-7 score ≥7.5, patient health questionnaire-9 score ≥5, glycated hemoglobin ≥6.4%, triglycerides ≥ 144 mg/dl, creatinine ≥ 0.85 mg/dl and albumin/creatinine ratio ≥ 26.5 are useful predictors of erectile dysfunction in men with type 2 diabetes, and the area under the curve for those variables was respectively 0.83, 0.76, 1, 0.75, 0.88, 0.72, 0.67 and 0.77. Finally, a linear regression analysis revealed that generalized anxiety disorder-7 was the only strong independent predictor of the international index of erectile function-5 (p < 0.001).

DISCUSSION AND CONCLUSION

Nesfatin-1 can be used as a biomarker for the severity of anxiety in erectile dysfunction patients with diabetes. Use of this molecule in treatment of diabetes and erectile dysfunction should be strengthened by larger studies. Psychiatric care must be offered to patients with diabetes and erectile dysfunction and low serum nesfatin-1 as they experience intense anxiety and depression.

Inhibition of NUCB2 suppresses the proliferation, migration, and invasion of rheumatoid arthritis synovial fibroblasts from patients with rheumatoid arthritis in vitro

Rheumatoid arthritis (RA) is an autoimmune polyarthritis in which synovial fibroblasts (SF) play a major role in cartilage and bone destruction through tumorlike proliferation, migration, and invasion. Nesfatin-1, an 82-amino-acid-long peptide discovered by Oh-I in 2006, is derived from the precursor protein nucleobindin-2 (NUCB2). NUCB2/nesfatin-1 promotes cell proliferation, migration, and invasion in various tumors. We have previously shown that increased nesfatin-1 levels in the synovium may be associated with disease severity in patients with RA. However, the effect of NUCB2 on the tumorlike transformation of RASF has not yet been reported. The expression of NUCB2 mRNA in the synovium of RA and non-RA patients was further confirmed using three individual datasets from the NCBI GEO database. Gene set enrichment analysis (GSEA) was employed to explore the association between NUCB2 mRNA and RA-related gene signatures or signaling pathways in the GSE77298 dataset. Cell proliferation, migration, and invasion abilities were determined using Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), wound healing, and transwell assays, respectively. The results showed that the levels of NUCB2 mRNA in the synovium were significantly elevated in patients with RA. Moreover, GSEA showed that high expression of NUCB2 mRNA was related to gene signatures, including those involved in the cell cycle, DNA replication, extracellular matrix-receptor interaction, and focal adhesion. Furthermore, the results of CCK-8 and EdU assays indicated that inhibition of NUCB2 markedly repressed RASF proliferation. Additionally, the results of wound healing and transwell assays demonstrated that inhibition of NUCB2 significantly suppressed the migratory and invasive abilities of RASFs. Our findings are the first to demonstrate that the inhibition of NUCB2 suppresses the proliferation, migration, and invasion of RASFs in vitro.

The modulatory effects of alkaloid extracts of Cannabis sativa, Datura stramonium, Nicotiana tabacum and male Carica papaya on neurotransmitter, neurotrophic and neuroinflammatory systems linked to anxiety and depression

This study investigated the modulatory effects of alkaloid extracts of Cannabis sativa (CSAE), Datura stramonium (DSAE), Nicotiana tabacum (NTAE) and male Carica papaya (CMAE) on neurotransmitter, neurotrophic and neuro-inflammatory systems linked to anxiety and depression. Male Wistar rats were orally administered the alkaloid extracts in doses of 5, 50, 500, and 2000 mg/kg for 90 days. On day 91, neurobehavioural studies were evaluated, rats were sacrificed, brain hippocampus removed and tissue homogenate prepared. Biochemical, cytokine and neurotransmitter metabolisms were estimated in the hippocampus. Expressions of genes linked to anxiety and depression were evaluated by RT-qPCR. Results showed CSAE, NTAE and CMAE act as anxiolytic and antidepressant agents by depleting TNF-α, IL-1β and reactive oxygen species concentrations, and monoamine oxidase, angiotensin 1-converting enzyme and acetylcholinesterase activities while elevating IL-10 and dopamine concentrations and glutamate dehydrogenase activity at doses of 5, 50 and 500. Same doses of CSAE, NTAE and CMAE also depleted the gene expressions of GSK3β, JNK, NF-ĸB, and Nesfatin-1 while increasing expressions of CREB, BDNF, serotonin and Nrf2. However, administration of DSAE and 2000 mg/kg CSAE, NTAE and CMAE had adverse modulatory effects on the neurochemical concentrations and activities as well as the gene expressions of the evaluated neurotransmitter, neurotrophic and inflammatory systems. In conclusion, the study established the sub-chronic instrumentalization potential of CSAE, CMAE, and NTAE for anxiolytic and anti-depressive moods, though their use may be associated with dependence and addiction, which may result in more detrimental effects than any therapeutic potential they may proffer.

NUCB2/nesfatin-1 is associated with severity of eating disorder symptoms in female patients with obesity

BACKGROUND

Nesfatin-1 has been described as an anorexigenic peptide. Comprehensive evidence also points towards an involvement of nesfatin-1 in the modulation of emotional pathways with a sex-specific regulation of nesfatin-1 in association with anxiety. Although the implication of nesfatin-1 in the regulation of food intake is well-established in animals, data in humans are lacking. Therefore, we investigated a possible association of circulating NUCB2/nesfatin-1 with eating disorder symptoms in female and male patients displaying a wide range of body weight.

METHODS

We enrolled 243 inpatients (177 female, 66 male) hospitalized due to anorexia nervosa (n = 66) or obesity (n = 144) or with normal weight and suffering from somatoform, adjustment, depressive or anxiety disorders (n = 33). Plasma samples (NUCB2/nesfatin-1 levels measured by ELISA) and measures of eating disorder symptoms (by EDI-2, range 0-100) were obtained within three days after admission.

RESULTS

The study population displayed a distinct prevalence of eating disorder symptoms with female patients with anorexia nervosa (+ 77.0%, p < 0.001) and obesity (+ 87.9%, p < 0.001) reported significantly higher EDI-2 scores than normal weight patients of the same sex. Accordingly, males with anorexia nervosa (+ 39.7%, p < 0.05) and obesity (+ 51.7%, p < 0.001) had significantly higher EDI-2 scores than males with normal weight. Within the same BMI group, women displayed significantly higher scores than men (+ 21.4%, p < 0.05 in patients with anorexia nervosa, + 18.8%, p < 0.001 in participants with obesity). We observed a positive correlation between NUCB2/nesfatin-1 levels and EDI-2 total scores in female patients with obesity (r = 0.285, p = 0.015), whereas no associations were found in other subgroups. A positive correlation between NUCB2/nesfatin-1 levels and BMI was only observed in the male study population (r = 0.315, p = 0.018).

CONCLUSIONS

NUCB2/nesfatin-1 plasma levels were positively associated with EDI-2 total scores in women with obesity, while no association was observable in men. The lacking association of NUCB2/nesfatin-1 and EDI-2 total scores in female patients with anorexia nervosa might be due to already low NUCB2/nesfatin-1 plasma levels. Whether NUCB2/nesfatin-1 is selectively involved in eating behavior in women with obesity will have to be further investigated.

Nesfatin-1 alleviated lipopolysaccharide-induced acute lung injury through regulating inflammatory response associated with macrophages modulation

Acute lung injury (ALI) is a continuum of lung changes associated with uncontrolled excessive lung inflammation. However, the pathogenesis of ALI is still complicated and effective clinical pharmacological management is required. Various signaling pathways are involved in the inflammatory responses of ALI. Here, we aimed to explore the role of nesfatin-1, an amino-acid peptide with anti-inflammatory action, in an LPS-induced ALI mice model, and its role in regulating macrophages in response to LPS stimulation in vitro. This was to clarify the underlying mechanisms of regulating the inflammatory response in the development of ALI. The results show that nesfatin-1 expression was downregulated in the lung tissues of ALI mice compared to control mice. Nesfatin-1 treatment ameliorated the inflammatory response and lung tissue damage in LPS-induced ALI in mice. In vitro studies showed that nesfatin-1 attenuated the generation and release of proinflammatory cytokines interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) in LPS-induced RAW 264.7 cells. Nesfatin-1 also inhibited reactive oxygen species production and improved superoxide dismutase (SOD) activity in LPS-induced RAW 264.7 cells. These findings suggest that nesfatin-1 exerted a crucial role in regulating the LPS-mediated activation of M1 macrophages. Further mechanism investigations indicated that nesfatin-1 inhibited the activation of p38 MAPK/c-Jun and NF-κB pathways in LPS-induced RAW 264.7 cells, as evidenced by decreased expression levels of p-p38, p-c-Fos, and p-p65. Overall, nesfatin-1 alleviated LPS-induced ALI, which might be attributed to regulating inflammatory response through macrophages modulation.

Escitalopram alters local expression of noncanonical stress-related neuropeptides in the rat brain via NPS receptor signaling

BACKGROUND

Neuropeptide S (NPS) is a multifunctional regulatory factor that exhibits a potent anxiolytic activity in animal models. However, there are no reports dealing with the potential molecular relationships between the anxiolytic activity of selective serotonin reuptake inhibitors (SSRIs) and NPS signaling, especially in the context of novel stress-related neuropeptides action. The present work therefore focused on gene expression of novel stress neuropeptides in the rat brain after acute treatment with escitalopram and in combination with neuropeptide S receptor (NPSR) blockade.

METHODS

Studies were carried out on adult, male Sprague-Dawley rats that were divided into five groups: animals injected with saline (control) and experimental rats treated with escitalopram (at single dose 10 mg/kg daily), escitalopram and SHA-68, a selective NPSR antagonist (at a single dose of 40 mg/kg), SHA-68 alone and corresponding vehicle (solvent SHA-68) control. To measure anxiety-like behavior and locomotor activity the open field test was performed. All individuals were killed under anaesthesia and the whole brain was excised. Total mRNA was isolated from homogenized samples of the amygdala, hippocampus, hypothalamus, thalamus, cerebellum, and brainstem. Real-time PCR was used for estimation of related NPS, NPSR, neuromedin U (NMU), NMU receptor 2 (NMUR2) and nesfatin-1 precursor nucleobindin-2 (NUCB2) gene expression.

RESULTS

Acute escitalopram administration affects the local expression of the examined neuropeptides mRNA in a varied manner depending on brain location. An increase in NPSR and NUCB2 mRNA expression in the hypothalamus and brainstem was abolished by SHA-68 coadministration, while NMU mRNA expression was upregulated after NPSR blockade in the hippocampus and cerebellum.

CONCLUSIONS

The pharmacological effects of escitalopram may be connected with local NPSR-related alterations in NPS/NMU/NMUR2 and nesfatin-1 gene expression at the level of selected rat brain regions. A novel alternative mode of SSRI action can be therefore cautiously proposed.

Effects of Modified Electroconvulsive Therapy on Serum Cortisol, Nesfatin-1, and Pro-inflammatory Cytokine Levels in Elderly Patients With Treatment-Resistant Depression

AIM

Modified electroconvulsive therapy (MECT) is an effective strategy for treatment-resistant depression (TRD); however, the mechanism underlying effects of MECT remains unclear. Accumulating evidence suggests that TRD is closely associated with dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, anorexigenic peptides, and pro-inflammatory cytokines. However, MECT effects on the HPA axis, anorexigenic peptides, and pro-inflammatory cytokines in elderly patients with TRD remain unclear. In this study, we investigated whether the HPA axis (cortisol), anorexigenic peptides (nesfatin-1), and pro-inflammatory cytokines (C-reactive protein, tumor necrosis factor-α, and interleukin-6, and interleukin-1β) are involved in the mechanism underlying MECT effects in elderly patients with TRD.

METHODS

Elderly patients with TRD were enrolled in this study between December 2019 and October 2021; all patients underwent MECT after physical examination. Serum cortisol, nesfatin-1, and pro-inflammatory cytokine levels were measured before and after the first, third, and sixth MECT sessions. The Hamilton Depression Rating Scale-24 (HAMD-24) and the Mini-Mental State Examination (MMSE) were used to evaluate depression and cognitive impairment, respectively. We compared pre- and post-MECT serum cortisol, nesfatin-1, and pro-inflammatory cytokine levels to confirm the short-term effects of MECT on these serum indices. We compared these serum indices across three time points (before the first, third, and sixth MECT sessions) to determine the long-term effects of MECT on serum cortisol, nesfatin-1, and pro-inflammatory cytokine levels.

RESULTS

We observed no statistically significant changes in the pre- and post-MECT serum cortisol, nesfatin-1, or pro-inflammatory cytokine levels. No significant changes in serum cortisol, nesfatin-1, and pro-inflammatory cytokine levels were observed across the aforementioned time points. Moreover, there were no statistically significant sex-based differences in the aforementioned serum indices. Furthermore, the serum cortisol level was negatively correlated with the serum IL-6 level before and after the first MECT session in patients with high cortisol levels (> the 50^th percentile value of all samples). Additionally, the post-MECT HAMD-24 and MMSE scores were significantly lower.

CONCLUSIONS

MECT reduced depressive symptoms despite an adverse effect on cognition and had no significant effect on the serum cortisol, nesfatin-1, and pro-inflammatory cytokine levels in elderly patients with TRD.

Role of the Novel Peptide Phoenixin in Stress Response and Possible Interactions with Nesfatin-1

The novel peptide phoenixin was shown to be involved in several physiological processes ranging from reproduction to food intake. Interest in this protein has steadily increased over the last few years and its known implications have become much broader, playing a role in glucose homeostasis, anxiety, nociception, and pruritus. Phoenixin is expressed in a multitude of organs such as the small intestine, pancreas, and in the hypothalamus, as well as several other brain nuclei influencing numerous physiological functions. Its highly conserved amino-acid sequence amongst species leads to the assumption, that phoenixin might be involved in essential physiological functions. Its co-expression and opposing functionality to the extensively studied peptide nesfatin-1 has given rise to the idea of a possible counterbalancing role. Several recent publications focused on phoenixin’s role in stress reactions, namely restraint stress and lipopolysaccharide-induced inflammation response, in which also nesfatin-1 is known to be altered. This review provides an overview on the phoenixins and nesfatin-1 properties and putative effects, and especially highlights the recent developments on their role and interaction in the response to response.

Neuropeptides of the human magnocellular hypothalamus

Hypothalamic magnocellular nuclei with their large secretory neurons are unique and phylogenetically conserved brain structures involved in the continual regulation of important homeostatic and autonomous functions in vertebrate species. Both canonical and newly identified neuropeptides have a broad spectrum of physiological activity at the hypothalamic neuronal circuit level located within the supraoptic (SON) and paraventricular (PVN) nuclei. Magnocellular neurons express a variety of receptors for neuropeptides and neurotransmitters and therefore receive numerous excitatory and inhibitory inputs from important subcortical neural areas such as limbic and brainstem populations. These unique cells are also densely innervated by axons from other hypothalamic nuclei. The vast majority of neurochemical maps pertain to animal models, mainly the rodent hypothalamus, however accumulating preliminary anatomical structural studies have revealed the presence and distribution of several neuropeptides in the human magnocellular nuclei. This review presents a novel and comprehensive evidence based evaluation of neuropeptide expression in the human SON and PVN. Collectively this review aims to cast a new, medically oriented light on hypothalamic neuroanatomy and contribute to a better understanding of the mechanisms responsible for neuropeptide-related physiology and the nature of possible neuroendocrinal interactions between local regulatory pathways.

Localization of Nucleobindin2/Nesfatin-1-Like Immunoreactivity in Human Lungs and Neutrophils

Nucleobindin2 (NUCB2)/nesfatin-1 expression in human plasma positively correlates with the expression of pro-inflammatory cytokines in patients with chronic obstructive pulmonary disease (COPD), implicating its potential role in neutrophilic lung inflammation. There are no data on the localization of nucleobindin2 (NUCB2)/nesfatin-1 in human lungs and inflammatory cells. We examined the localization of NUCB2/nesfatin-1-immunoreactivity in normal and inflamed human lungs obtained from COPD patients and neutrophils with light and immunoelectron microscopy. Immunohistology showed localization of NUCB2/nesfatin-1-like immunoreactivity in the bronchiolar epithelium, alveolar septa, vascular endothelium and various immune cells of normal and inflamed lungs. Further, NUCB2/nesfatin-1-like immunoreactivity accumulated within 0.5 μm of the plasma membrane in human neutrophils following 90 min. of 1 ng/mL LPS stimulation. NUCB2/nesfatin-1-like immunoreactivity was also found to localize in euchromatic portions of neutrophilic nuclei at five times the mean concentration compared to heterochromatin. Finally, our results indicate that NUCB2/nesfatin-1-like immunoreactivity is predominantly cytoplasmic including that in the Golgi complex and vesicles as it localizes at two times the concentration in neutrophilic cytoplasm compared to nucleus. Our study is the first to detail the localization of NUCB2/nesfatin-1-like immunoreactivity in lungs and neutrophils, and nuclear localization of NUCB2/nesfatin-1 also implicates its potential role in transcriptional regulation.

Evaluation of Appetite-Regulating Hormones ın Young Children with Autism Spectrum Disorder

This study aimed to investigate the role of leptin, ghrelin, neuropeptide Y, and nesfatin-1 in young children with autism spectrum disorder (ASD). A total of 44 children with ASD and 44 healthy controls aged 18-60 months were included. Plasma levels of hormones were measured using commercial enzyme-linked immunosorbent assay kits. Plasma leptin and ghrelin levels were significantly higher in the ASD group than in the control group. However, no significant difference for plasma neuropeptide Y and nesfatin-1 levels was detected between the groups. No relation was found between the severity of ASD symptoms, severity of eating problems, and plasma levels of hormones. Leptin and ghrelin may play a potential role in the pathogenesis of ASD.

Reduction in Nesfatin-1 Levels in the Cerebrospinal Fluid and Increased Nigrostriatal Degeneration Following Ventricular Administration of Anti-nesfatin-1 Antibody in Mice

Nesfatin-1 is one of several brain-gut peptides that have a close relationship with the central dopaminergic system. Our previous studies have shown that nesfatin-1 is capable of protecting nigral dopaminergic neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity. A recent study also revealed a reduced blood level of nesfatin-1 in patients with Parkinson’s disease (PD). The current study was designed to investigate whether reduced nesfatin-1 in cerebrospinal fluid (CSF) induces nigrostriatal system degeneration. An intra-cerebroventricular (ICV) injection technique was used to administer anti-nesfatin-1 antibody directly into the lateral ventricle of the brain. Enzyme-linked immunosorbent assay (ELISA) results showed that ICV injection of anti-nesfatin-1 antibody into the lateral ventricle of the brain once daily for 2 weeks caused a significant reduction in nesfatin-1 levels in the CSF (93.1%). Treatment with anti-nesfatin-1 antibody resulted in a substantial loss (23%) of TH-positive (TH+) dopaminergic neurons in the substantia nigra pars compacta (SNpc), as shown by immunofluorescence staining, a depletion in dopamine and its metabolites in the striatum detected by high-performance liquid chromatography (HPLC), and obvious nuclear shrinkage and mitochondrial lesions in dopaminergic neurons in the SNpc detected by transmission electron microscopy (TEM). Furthermore, the results from our Western blot and ELISA experiments demonstrated that anti-nesfatin-1 antibody injection induced an upregulation of caspase-3 activation, increased the expression of p-ERK, and elevated brain-derived neurotrophic factor (BDNF) levels in the SNpc. Taken together, these observations suggest that reduced nesfatin-1 in the brain may induce nigrostriatal dopaminergic system degeneration; this effect may be mediated via mitochondrial dysfunction-related apoptosis. Our data support a role of nesfatin-1 in maintaining the normal physiological function of the nigrostriatal dopaminergic system.

Plasma Nesfatin-1: Potential Predictor and Diagnostic Biomarker for Cognitive Dysfunction in T2DM Patient

PURPOSE

Nesfatin-1 plays a crucial role in glucose metabolism and cognitive function. This study aimed to investigate the correlation between plasma nesfatin-1 levels and clinical indicators and cognitive function in patients with type 2 diabetes mellitus (T2DM).

METHODS

Demographic and medical history data, physical examination, and biochemical test results of 132 T2DM patients were collected. The plasma concentrations of nesfatin-1, C-reactive protein (CRP), interleukin-6 (IL-6), soluble triggering receptors expressed on myeloid cells 1 (sTREM1), and sTREM2 in T2DM patients were measured. Cognitive function was evaluated using the Behavior Rating Inventory of Executive Function-Adult (BRIEF-A). The patients were divided into two groups: a low-nesfatin-1 group (n = 75) and a high-nesfatin-1 group (n = 57) based on a plasma nesfatin-1 concentration less than or above the 50th percentile value of all the samples.

RESULTS

The results showed that plasma HbA1c levels were positively correlated with CRP, IL-6, sTREM1, and sTREM2 levels in patients with T2DM (P < 0.05). Plasma nesfatin-1 concentrations were positively associated with diabetes-related biochemical indicators including glycated haemoglobin (HbA1c), insulin, and homeostatic model assessment of insulin resistance (HOMA-IR), and inflammation-related indicators including CRP, IL-6, sTREM1, and sTREM2 among patients with T2DM (P < 0.05). Moreover, T2DM patients with high nesfatin-1 levels showed higher HbA1c and fasting plasma glucose (FPG) levels (P < 0.05). Furthermore, T2DM patients with high nesfatin-1 levels also showed higher BRIEF-A scores (P = 0.01). Additionally, T2DM patients with high total scores of BRIEF-A (scores > 50th percentile) could be identified with a sensitivity of 59.1% and a specificity of 72.7% by nesfatin-1.

CONCLUSION

These findings indicate that plasma nesfatin-1 might be involved in the T2DM-associated comorbidities and the development of cognitive dysfunction, and the mechanism underlying this involvement is related to the imbalance in the expression of CRP, IL-6, sTREM1, and sTREM2 levels.

Restraint stress affects circulating NUCB2/nesfatin-1 and phoenixin levels in male rats

The two peptides phoenixin and nesfatin-1 are colocalized in hypothalamic nuclei involved in the mediation of food intake and behavior. Phoenixin stimulates food intake and is anxiolytic, while nesfatin-1 is an anorexigenic peptide shown to increase anxiety and anhedonia. Interestingly, central activation of both peptides can be stimulated by restraint stress giving rise to a role in the mediation of stress. Thus, the aim of the study was to test whether also peripheral circulating levels of NUCB2/nesfatin-1 and phoenixin are altered by restraint stress. Male ad libitum fed Sprague Dawley rats equipped with a chronic intravenous catheter were subjected to restraint stress and plasma levels of NUCB2/nesfatin-1, phoenixin and cortisol were measured over a period of 240 min and compared to levels of freely moving rats. Peripheral cortisol levels were significantly increased in restrained rats at 30, 60, 120 and 240 min compared to controls (p < 0.05). In contrast, restraint stress decreased plasma phoenixin levels at 15 min compared to unstressed conditions (0.8-fold, p < 0.05). Circulating NUCB2/nesfatin-1 levels were increased only at 240 min in restrained rats compared to those in unstressed controls (1.3-fold, p < 0.05). In addition, circulating NUCB2/nesfatin-1 levels correlated positively with phoenixin levels (r = 0.378, p < 0.001), while neither phoenixin nor nesfatin-1 were associated with cortisol levels (r = 0.0275, and r=-0.143, p> 0.05). These data suggest that both peptides, NUCB2/nesfatin-1 and phoenixin, are affected by restraint stress, although less pronounced than circulating cortisol.

Nesfatin-1 and neuronostatin neurons are co-expressed with glucocorticoid receptors in the hypothalamus

Nesfatin-1 and neuronostatin in the central nervous system participate in regulating stress responses. Glucocorticoid hormones affect the brain through glucocorticoid receptors (GR). We investigated in the rat the possibility of co-localizing nesfatin-1 and neuronostatin neurons in hypothalamic areas with GR. using immunohistochemistry. We counted nesfatin-1 and neuronostatin stained neurons. We counted GR positive nesfatin-1 neurons in the arcuate nucleus (ARC) and paraventricular nucleus (PVN) and GR positive neuronostatin neurons in the periventricular nucleus (PeN). The percentage of nesfatin-1 neurons that expressed GR was 38.4% in female rats and 21.9% in male rats in the ARC, and 33.3% in female rats and 29.2% in male rats in the PVN. The percentage of neuronostatin neurons that expressed GR was 39.1% in female rats and 39.9% in male rats in the PeN. We found that a substantial portion of nesfatin-1 and neuronostatin neurons were stained for GR. We speculate that the pattern of GR might permit secretion of neuropeptides to be stimulated by peripheral glucocorticoid signals. Stress can suppress food intake, in part, through the GR in neurons that express nesfatin-1, which is a satiety molecule, and in neurons that express neuronostatin, which is an anorexigenic peptide.

Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities of Nesfatin-1: A Review

Nesfatin-1, a newly identified energy-regulating peptide, is widely expressed in the central and peripheral tissues, and has a variety of physiological activities. A large number of recent studies have shown that nesfatin-1 exhibits antioxidant, anti-inflammatory, and anti-apoptotic properties and is involved in the occurrence and progression of various diseases. This review summarizes current data focusing on the therapeutic effects of nesfatin-1 under different pathophysiological conditions and the mechanisms underlying its antioxidant, anti-inflammatory, and anti-apoptotic activities.

Nesfatin-1 Hormone Levels in Patients with Antisocial Personality Disorder and Their Relationship with Clinical Variables

OBJECTIVE

This study aims to investigate the levels of nesfatin-1-hormone in patients with Antisocial Personality Disorder (ASPD) and their relationship with clinical variables.

METHODS

A total of 90 people (45 ASPD, 45 controls) were included in our study. Sociodemographic Data Form, Beck-Depression-Inventory (BDI), Beck-Anxiety-Inventory (BAI), Barratt Impulsivity Scale (BIS-11), Buss-Durkee-Hostility-Inventory (BDHI) were applied to all participants. Venous blood samples were taken from participants at the same time of the day when they were hungry.

RESULTS

It was found that the BDI and BAI scores of the ASPD were higher than those of the controls (p<0.001, for both scales). The scores in BIS-11; motor and nonplanning-impulsivity subscales were higher than those of the controls (p<0.001, 0.036, respectively). The scores obtained by the ASPD were higher in all subscales of BDHI (p<0.001). For the nesfatin-1-hormone, the values of the ASPD were lower than those of the controls (p=0.044). No relationship was found between the nesfatin-1-hormone and any other laboratory parameters and applied scales (p>0.05).

CONCLUSION

This is the first study to examine the nesfatin-1-hormone levels in patients with any personality disorder. Further studies with more participants are needed in different types of personality disorders to understand the relationship between personality disorder and nesfatin-1-hormone levels.

Quercetin Alleviates LPS-Induced Depression-Like Behavior in Rats via Regulating BDNF-Related Imbalance of Copine 6 and TREM1/2 in the Hippocampus and PFC

Quercetin is a polyphenol with multiple biological activities, and results of our preliminary study showed that it could shorten the immobility time of mice in the forced swimming test and tail suspending test. The aim of this study was to investigate its effects on the behavioral performance of lipopolysaccharide (LPS)-challenged rats and explore the potential mechanism. The results showed that intragastrical administration of quercetin (40 mg/kg) could improve the bodyweight gain of LPS-challenged rats, increase the saccharin preference index in the saccharin preference test and the novel arm preference index in the Y-maze, and decrease the immobility time in the FST. However, it showed no significant effect on the performance of LPS-challenged rats in the Morris water maze and the plasma concentrations of nesfatin-1, C-reactive protein (CRP), and IL-6. Results of western blot showed that the expression levels of BDNF, Copine 6, p-TrkB, and the triggering receptors expressed on myeloid cells (TREM) 1 were decreased in both the hippocampus and the prefrontal cortex (PFC) of LPS-challenged rats, while the expression of TREM2 was increased. The protein expression of synapsin-1 was decreased in the hippocampus without significant changes in the PFC. These imbalance protein expressions could be balanced by treatment with quercetin. The results suggested that quercetin could alleviate LPS-induced depression-like behaviors and impairment of learning and memory in rats, the mechanism of which might be involved with regulating the BDNF-related imbalance expression of Copine 6 and TREM1/2 in the hippocampus and the PFC.

Animal Models for Functional Gastrointestinal Disorders

Functional gastrointestinal disorders (FGID), such as functional dyspepsia (FD) and irritable bowel syndrome (IBS) are characterized by chronic abdominal symptoms in the absence of an organic, metabolic or systemic cause that readily explains these complaints. Their pathophysiology is still not fully elucidated and animal models have been of great value to improve the understanding of the complex biological mechanisms. Over the last decades, many animal models have been developed to further unravel FGID pathophysiology and test drug efficacy. In the first part of this review, we focus on stress-related models, starting with the different perinatal stress models, including the stress of the dam, followed by a discussion on neonatal stress such as the maternal separation model. We also describe the most commonly used stress models in adult animals which brought valuable insights on the brain-gut axis in stress-related disorders. In the second part, we focus more on models studying peripheral, i.e., gastrointestinal, mechanisms, either induced by an infection or another inflammatory trigger. In this section, we also introduce more recent models developed around food-related metabolic disorders or food hypersensitivity and allergy. Finally, we introduce models mimicking FGID as a secondary effect of medical interventions and spontaneous models sharing characteristics of GI and anxiety-related disorders. The latter are powerful models for brain-gut axis dysfunction and bring new insights about FGID and their comorbidities such as anxiety and depression.

Evidence of a Relationship Between Plasma Leptin, Not Nesfatin-1, and Craving in Male Alcohol-Dependent Patients After Abstinence

The goal of this study was to determine whether the plasma leptin, nesfatin-1, cortisol, brain-derived neurotrophic factor (BDNF), and inflammatory cytokines could be used as potential biomarkers for the degree of craving in the alcohol-dependent patients after 1 month of abstinence. A total of 83 patients with alcohol use disorder (AUD) and 61 healthy subjects were assessed. Patients with AUD were selected from Department of Material Dependence, Anhui Mental Health Center, and subjects in the control group were selected from healthy volunteers. The Alcohol Urge questionnaire Scale (AUQ) was used to evaluate the extent of craving for alcohol, and the Michigan Alcoholism Screening Test (MAST), the Fagerstrom Test for Nicotine Dependence (FTND), the Self-Rating Anxiety Scale (SAS), and the Self-Rating Depression Scale (SDS) were also assessed in patients with AUD. Enzyme-Linked Immunosorbent Assay (ELISA) was used for the measurement of plasma leptin, nesfatin-1, cortisol, BDNF, Interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) levels. Compare with healthy controls, the average leptin, leptin/BMI, IL-6, CRP, and TNF-α levels in patients with AUD were significantly increased, while the BDNF levels were significantly decreased. Moreover, the partial correlational analysis showed that the AUQ scores of the alcohol-dependent patients were positively correlated with the plasma leptin levels (r = 0.613, P < 0.001), rather than nesfatin-1 (r = 0.066, P = 0.569) after controlling for age as covariate. Furthermore, plasma nesfatin-1 levels were found to be correlated with the SDS scores (r = 0.366, P = 0.001) in the AUD group. In addition, plasma leptin levels were positively associated with the plasma IL-6 (r = 0.257, P = 0.033), CRP (r = 0.305, P = 0.011), and TNF-α (r = 0.311, P = 0.009) levels, and negatively associated with the BDNF levels (r = -0.245, P = 0.042) in patients with AUD. These results suggest that plasma leptin, but not nesfatin-1, might be a potential biomarker for the degree of craving in alcohol-dependent patients after 1 month of abstinence, the mechanism of which might be related to the dysfunction of the inflammatory cytokines and BDNF levels.

Nucleobindins and encoded peptides: From cell signaling to physiology

Nucleobindins (NUCBs) are DNA and calcium binding, secreted proteins with various signaling functions. Two NUCBs, nucleobindin-1 (NUCB1) and nucleobindin-2 (NUCB2), were discovered during the 1990s. These two peptides are shown to have diverse functions, including the regulation of inflammation and bone formation, among others. In 2006, Oh-I and colleagues discovered that three peptides encoded within the NUCB2 could be processed by prohormone convertases. These peptides were named nesfatin-1, 2 and 3, mainly due to the satiety and fat influencing properties of nesfatin-1. However, it was found that nesfatin-2 and -3 have no such effects. Nesfatin-1, especially its mid-segment, is very highly conserved across vertebrates. Although the receptor(s) that mediate nesfatin-1 effects are currently unknown, it is now considered an endogenous peptide with multiple functions, affecting central and peripheral tissues to regulate metabolism, reproduction, endocrine and other functions. We recently identified a nesfatin-1-like peptide (NLP) encoded within the NUCB1. Like nesfatin-1, NLP suppressed feed intake in mice and fish, and stimulated insulin secretion from pancreatic beta cells. There is considerable evidence available to indicate that nucleobindins and its encoded peptides are multifunctional regulators of cell biology and whole animal physiology. This review aims to briefly discuss the structure, distribution, functions and mechanism of action nucleobindins and encoded peptides.

The first identification of nesfatin-1-expressing neurons in the human bed nucleus of the stria terminalis

Neuropeptides are involved in various brain activities being able to control a wide spectrum of higher mental functions. The purpose of this concise structural investigation was to detect the possible immunoreactivity of the novel multifunctional neuropeptide nesfatin-1 within the human bed nucleus of the stria terminalis (BNST). The BNST is involved in the mechanism of fear learning, integration of stress and reward circuits, and pathogenesis of addiction. Nesfatin-1-expressing neurons were identified for the first time in several regions of the BNST using both immunohistochemical and fluorescent methods. This may implicate a potential contribution of this neuropeptide to the BNST-related mechanisms of stress/reward responses in the human brain.

Resveratrol Reduces Glucolipid Metabolic Dysfunction and Learning and Memory Impairment in a NAFLD Rat Model: Involvement in Regulating the Imbalance of Nesfatin-1 Abundance and Copine 6 Expression

Resveratrol (RES) is a polyphenolic compound, and our previous results have demonstrated its neuroprotective effect in a series of animal models. The aim of this study was to investigate its potential effect on a nonalcoholic fatty liver disease (NAFLD) rat model. The parameters of liver function and glucose and lipid metabolism were measured. Behavior performance was observed via the open field test (OFT), the sucrose preference test (SPT), the elevated plus maze (EPM), the forced swimming test (FST), and the Morris water maze (MWM). The protein expression levels of Copine 6, p-catenin, catenin, p-glycogen synthase kinase-3beta (GSK3β), GSK3β, and cyclin D1 in the hippocampus and prefrontal cortex (PFC) were detected using Western blotting. The results showed that RES could reverse nesfatin-1-related impairment of liver function and glucolipid metabolism, as indicated by the decreased plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), glucose, insulin, and nesfatin-1; increase the plasma level of high-density lipoprotein cholesterol (HDL-C); and reduce hepatocyte steatosis in NAFLD rats. Although there was no significant difference among groups with regard to performance in the OFT, EPM, and FST tasks, RES-treated NAFLD rats showed an increased sucrose preference index in the SPT and improved learning and memory ability in the MWM task. Furthermore, the imbalanced protein expression levels of Copine 6, p-catenin, and p-GSK3β in the hippocampus and PFC of NAFLD rats were also restored to normal by treatment with RES. These results suggested that four consecutive weeks of RES treatment not only ameliorated glucolipid metabolic impairment and liver dysfunction in the NAFLD rat model but also mitigated the attendant behavioral and cognitive impairments. In addition to the mediating role of nesfatin-1, the mechanism underlying the therapeutic effect of RES on NAFLD might be associated with its ability to regulate the imbalanced expression level of Copine 6 and the Wnt signaling pathway in the hippocampus and PFC.

Xiaoyaosan Ameliorates Chronic Immobilization Stress-Induced Depression-Like Behaviors and Anorexia in Rats: The Role of the Nesfatin-1-Oxytocin-Proopiomelanocortin Neural Pathway in the Hypothalamus

Background: Chronic stress is an important risk factor for depression. The nesfatin-1 (NES1)-oxytocin (OT)-proopiomelanocortin (POMC) neural pathway, which is involved in the stress response, was recently shown to have an anorectic effect in the hypothalamus. Our previous study showed that Xiaoyaosan, a well-known antidepressant used in traditional Chinese medicine, effectively relieved appetite loss induced by chronic immobilization stress (CIS). However, whether Xiaoyaosan ameliorates depression-like behaviors and anorexia by regulating the NES1-OT-POMC neural pathway remains unclear. Objective: To investigate whether the antidepressant-like and anti-anorexia effects of Xiaoyaosan are related to the NES1-OT-POMC neural pathway in the hypothalamus. Methods: Rats were randomly divided into control, CIS, Xiaoyaosan treatment, and fluoxetine treatment groups. The rats in the CIS, Xiaoyaosan treatment, and fluoxetine treatment groups were subjected to CIS for 21 consecutive days, during which they were administered distilled water, a Xiaoyaosan decoction [3.854 g/(kg·d)] or fluoxetine [1.76 mg/(kg·d)], respectively, by gavage, and their body weights and food intake were monitored daily. The rats were subsequently subjected to the open field test and sucrose preference test. Then, the expression levels of corticosterone and NES1 in the serum and the expression levels of NES1, OT, POMC, and melanocortin-4 receptor (MC4R) in the hypothalamus were determined by real-time fluorescence quantitative polymerase chain reaction, Western blot analysis, and immunochemistry. Furthermore, immunofluorescence double staining was used to determine whether related proteins in the hypothalamic NES1-OT-POMC neural pathway were co-expressed. Results: Compared to control rats, rats exposed to CIS exhibited gradually less food intake and lower body weights and significantly increased concentrations of NES1 in the serum and paraventricular nucleus. Moreover, the expression levels of POMC, OT, and MC4R in the hypothalamus were significantly higher in the CIS group than those in the control group. However, these changes were reversed by pretreatment with Xiaoyaosan and fluoxetine. Specifically, the expression levels of members of the NES1-OT-POMC neural pathway were lower in the Xiaoyaosan-treated group than in the CIS group. Conclusion: Xiaoyaosan ameliorates CIS-induced depression-like behaviors and anorexia by regulating the NES1-OT-POMC neural pathway in the hypothalamus.