• Molecules and Cells
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• v.43 no.5
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• pp.431-437
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• 2020

The hypothalamus is a crucial organ for the maintenance of appropriate body fat storage. Neurons in the hypothalamic arcuate nucleus (ARH) detect energy shortage or surplus via the circulating concentrations of metabolic hormones and nutrients, and then coordinate energy intake and expenditure to maintain energy homeostasis. Malfunction or loss of hypothalamic ARH neurons results in obesity. Accumulated evidence suggests that hypothalamic inflammation is a key pathological mechanism that links chronic overconsumption of a high-fat diet (HFD) with the development of obesity and related metabolic complications. Interestingly, overnutrition-induced hypothalamic inflammation occurs specifically in the ARH, where microglia initiate an inflammatory response by releasing proinflammatory cytokines and chemokines in response to excessive fatty acid flux. Upon more prolonged HFD consumption, astrocytes and perivascular macrophages become involved and sustain hypothalamic inflammation. ARH neurons are victims of hypothalamic inflammation, but they may actively participate in hypothalamic inflammation by sending quiescence or stress signals to surrounding glia. In this mini-review, we describe the current state of knowledge regarding the contributions of neurons and glia, and their interactions, to HFD-induced hypothalamic inflammation.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.255-264
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• 2023

Background: Red ginseng (RG) alleviates psychiatric disorders. Fermented red ginseng (fRG) alleviates stress-induced gut inflammation. Gut dysbiosis causes psychiatric disorders with gut inflammation. To understand the gut microbiota-mediated action mechanism of RG and fRG against anxiety/depression (AD), we investigated the effects of RG, fRG, ginsenoside Rd, and 20(S)-β-D-glucopyranosyl protopanaxadiol (CK) on gut microbiota dysbiosis-induced AD and colitis in mice. Methods: Mice with AD and colitis were prepared by exposing to immobilization stress (IS) or transplanting the feces of patients with ulcerative colitis and depression (UCDF). AD-like behaviors were measured in the elevated plus maze, light/dark transition, forced swimming, and tail suspension tests. Results: Oral gavage of UCDF increased AD-like behaviors and induced neuroinflammation, gastrointestinal inflammation, and gut microbiota fluctuation in mice. Oral administration of fRG or RG treatment reduced UCDF-induced AD-like behaviors, hippocampal and hypothalamic IL-6 expression, and blood corticosterone level, whereas UCDF-suppressed hippocampal BDNF⁺NeuN⁺ cell population and dopamine and hypothalamic serotonin levels increased. Furthermore, their treatments suppressed UCDF-induced colonic inflammation and partially restored UCDF-induced gut microbiota fluctuation. Oral administration of fRG, RG, Rd, or CK also decreased IS-induced AD-like behaviors, blood IL-6 and corticosterone and colonic IL-6 and TNF-α levels, and gut dysbiosis, while IS-suppressed hypothalamic dopamine and serotonin levels increased. Conclusion: Oral gavage of UCDF caused AD, neuroinflammation, and gastrointestinal inflammation in mice. fRG mitigated AD and colitis in UCDF-exposed mice by the regulation of the microbiota-gut-brain axis and IS-exposed mice by the regulation of the hypothalamic-pituitary-adrenal axis.

• Korean Journal of Biological Psychiatry
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• v.18 no.4
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• pp.169-175
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• 2011

Stress, a risk factor of major depression induces cytokine mediated inflammation and decreased neurogenesis. In patients with major depression, significant increases of pro-inflammatory cytokines have been consistently reported. The pro-inflammatory cytokines can stimulate the hypothalamic-pituitary-adrenal (HPA) axis to release glucocorticoids. In the brain, microglia and play a role of immune activation in response to stress. Increased pro-inflammatory cytokine play a role in restricting neurogenesis in the brain. Although neurogenesis may not be essential for the development of depression, it may be required for clinically effective antidepressant treatment. Hence, stimulation of neurogenesis is regarded as a promising strategy for new antidepressant targets. This review introduces changes in neurotransmitter, cytokine and neurogenesis in major depression and explores the possible relationship between pro-inflammatory cytokines and neurogenesis related to stress in major depression.

• Women's Health Nursing
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• v.21 no.2
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• pp.106-114
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• 2015

Purpose: The purpose of this review was to describe a psychoneuroimmunology (PNI) framework for postpartum depression (PPD) and discuss its implications for nursing research and practice for postpartum women. Methods: This study explored the role of hypothalamic-pituitary-adrenal (HPA) axis and inflammation as possible mediators of risk factors for PPD through literature review. Results: From this PNI view, human bodies are designed to respond with the reciprocal interactions among the neuro-endocrine and immune system when they are faced with physical or psychological stressors. Chronic stress induces alterations in the function of HPA axis, and a chronic low-grade inflammatory response is associated with depression. The dysfunctions of cytokines and HPA axis have been observed during the postpartum period. Stress promotes glucocorticoid receptor resistance, which can promote inflammatory responses. This, in turn, can contribute to the pathophysiology of depression. This can especially affect populations at vulnerable time-points, such as women in the postpartum. Conclusion: From a PNI perspective, well-designed prospective research evaluating the role of stress and inflammation as an etiology of PPD and the effect of stress reduction is warranted to prevent PPD.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.83-90
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• 2013

Objectives : Tetramethylpyrazine (TMP) is an active ingredient in Ligusticum wallichii and has a wide range of neuroprotection effects. This study investigated anti-neuroinflammatory effect of TMP on brain regions in intracerebroventricular (i.c.v.) lipopolysaccharide (LPS)-treated C57BL/6 mice. Methods : TMP was administered intraperitoneally at doses of 10, 20, and 30 mg/kg at 1 h prior to LPS (3 mg/kg) i.c.v. injection. mRNA level of pro-inflammatory cytokines, including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$ and IL-6, was measured in the cerebral cortex, hippocampus, and hypothalamus tissue using real-time polymerase chain reaction at 24 h after the LPS injection. Cyclooxygenase-2 (COX-2) positive cells in the hypothalamus was also observed using immunohistochemistry at 24 h after the LPS injection. Results : At a dose of 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$ and IL-$1{\beta}$ mRNA in the cerebral cortex and IL-$1{\beta}$ mRNA in the hippocampus. In the hypothalamus, doses of 20 mg/kg and 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 mRNA induced by the LPS injection. In addition, TMP (30 mg/kg) significantly reduced the number of COX-2 positive cells in the hypothalamus. Conclusion : These results indicate that TMP has an anti-inflammatory effect on neuroinflammation, especially in the hypothalamus, induced by LPS i.c.v. injection and suggest that TMP-containing Ligusticum wallichii may play a modulatory role on the systemic responses following hypothalamic inflammation.

• The Korea Journal of Herbology
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• v.30 no.1
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• pp.77-84
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• 2015

Objectives : Brain inflammation early activates the microglia and activated microglia secrete a variety of pro-inflammatory cytokines. Kaempferol, which is a flavonoid in Cuscutae Semen, shows a wide range of physiological activities, including neurons protection and anti-inflammatory actions through inhibition of pro-inflammatory mediators. The present study examined the modulatory effect of kaempferol on cytokines [tumor necrosis factor- alpha ($TNF-{\alpha}$), interleukin-1beta ($IL-1{\beta}$) and interleukin-6 (IL-6)] and cyclooxygenase-2 (COX-2) mRNA expression and microglia activation in the brain tissue of the mouse. Methods : Kaempferol was administered orally three doses of 10, 20 and 30 mg/kg respectively, once 1 hour before the lippolysaccharide(LPS) (3 mg/kg, i.p.) injection. Brain tissue was removed at 4 hours after LPS injection. Cytokines and COX-2 mRNA expression in the brain tissue was measured by the quantitative real-time polymerase chain reaction (PCR) method. Iba1 expression was calculated by western blotting method. Microglia was observed with immunohistochemistry. Immunohistochemistry stained microglia was analyzed by using ImageJ software. Results : Kaempferol 20 and 30 mg/kg was significantly attenuated the expression of $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 mRNA. Kaempfrol 10, 20 and 30 mg/kg significantly attenuated COX-2 mRNA expression in the brain tissue. Kaempferol 30 mg/kg significantly suppressed the increase of Iba1 protein expression by LPS. Kaempferol 30 mg/kg significantly decreased the number of microglia in the cerebral cortex and the number and cell size of microglia in the hypothalamic region and the area percentage of ionized calcium binding adaptor molecule 1(Iba1)-expressed microglia in the hippocampus. Conclusions : This results indicate that kaempferol plays an anti-inflammatory role in the brain.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.422-433
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• 2018

Objective: Neuropsychiatric manifestations like depression and cognitive dysfunction commonly occur in inflammatory bowel disease (IBD). In the context of the brain-gut axis model, colitis can lead to alteration of brain function in a bottom-up manner. Here, the changes in the response of the hypothalamic-pituitary-adrenal axis and inflammation-related markers in the brain in colitis were studied. Methods: Dextran sodium sulfate (DSS) was used to generate a mouse model of colitis. Mice were treated with DSS for 3 or 7 days and sacrificed. We analyzed the gene expression of brain-derived neurotrophic factor (BDNF), cyclooxygenase 2 (COX-2), and glial fibrillary acidic protein (GFAP), and the expression of GFAP, in the hippocampus, hypothalamus, and amygdala. Additionally, the levels of C-reactive protein (CRP) and serum cortisol/corticosterone were measured. Results: Alteration of inflammatory-related markers varied depending on the brain region and exposure time. In the hippocampus, COX-2 mRNA, GFAP mRNA, and GFAP expression were upregulated during exposure to DSS. However, in the hypothalamus, COX-2 mRNA was upregulated only 3 days after treatment. In the amygdala, BDNF and COX-2 mRNAs were downregulated. CRP and corticosterone expression increased with DSS treatment at day 7. Conclusion: IBD could lead to neuroinflammation in a bottom-up manner, and this effect varied according to brain region. Stress-related hormones and serum inflammatory markers, such as CRP, were upregulated from the third day of DSS treatment. Therefore, early and active intervention is required to prevent psychological and behavioral changes caused by IBD, and region-specific studies can help understand the precise mechanisms by which IBD affects the brain.

• Journal of Korean Academy of Nursing
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• v.43 no.5
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• pp.579-586
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• 2013

Purpose: This article provides an update and overview of a nursing research program focused on understanding the pathophysiology and management of irritable bowel syndrome (IBS). Methods: This review includes English language papers from the United States, Europe, and Asia (e.g., South Korea) from 1999 to 2013. We addressed IBS as a health problem, emerging etiologies, diagnostic and treatment approaches and the importance of a biopsychosocial model. Results: IBS is a chronic, functional gastrointestinal disorder characterized by recurrent episodes of abdominal pain and alterations in bowel habit (diarrhea, constipation, mixed). It is a condition for which adults, particularly women ages 20-45, seek health care services in both the United States and South Korea. Clinically, nurses play key roles in symptom prevention and management including designing and implementing approaches to enhance the patients' self-management strategies. Multiple mechanisms are believed to participate in the development and maintenance of IBS symptoms including autonomic nervous system dysregulation, intestinal inflammation, intestinal dysbiosis, dietary intolerances, alterations in emotion regulation, heightened visceral pain sensitivity, hypothalamic-pituitary-adrenal dysregulation, and dysmotility. Because IBS tends to occur in families, genetic factors may also contribute to the pathophysiology. Patients with IBS often report a number of co-morbid disorders and/or symptoms including poor sleep. Conclusion: The key to planning effective management strategies is to understand the heterogeneity of this disorder. Interventions for IBS include non-pharmacological strategies such as cognitive behavior therapy, relaxation strategies, and exclusion diets.

• YAKHAK HOEJI
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• v.60 no.1
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• pp.8-14
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• 2016

Endotoxemia induces production of inflammatory mediators and acute phase proteins, leading to multiorgan injury and systemic inflammation. Hypothalamic-pituitary-adrenal (HPA) axis activation and glucocorticoids (GCs) release modify endotoxemia-induced inflammatory responses. In the present study, we investigated whether pre-exposure of GCs influences endotoxin-induced production of inflammatory mediators in hepatocytes. Hepa1c1c-7 cells were pretreated with low concentrations of corticosterone for 24 h and then cultured without corticosterone in the presence or absence of LPS. Our results demonstrated that LPS alone significantly enhanced production of IL-6 and CRP but reduced vascular endothelial growth factor (VEGF) compared to controls. Combination of corticosterone pretreatment and LPS significantly upregulated production of IL-6, IL-$1{\beta}$, and VEGF but downregulated CRP compared to those in LPS alone. These findings suggest that in low concentration of corticosterone-preexposed hepatocytes, endotoxemia may induce upregulation of IL-6, IL-$1{\beta}$, VEGF and but downregulation of CRP.

• Molecules and Cells
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• v.41 no.3
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• pp.244-255
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• 2018

Low-grade pro-inflammatory state and leptin resistance are important underlying mechanisms that contribute to obesity-associated hypertension. We tested the hypothesis that Astragaloside IV (As IV), known to counteract obesity and hypertension, could prevent obesity-associated hypertension by inhibiting pro-inflammatory reaction and leptin resistance. High-fat diet (HFD) induced obese rats were randomly assigned to three groups: the HFD control group (HF con group), As IV group, and the As IV + ${\alpha}$-bungaratoxin (${\alpha}-BGT$) group (As IV+${\alpha}-BGT$ group). As IV ($20mg{\cdot}Kg^{-1}{\cdot}d^{-1}$) was administrated to rats for 6 weeks via daily oral gavage. Body weight and blood pressure were continuously measured, and NE levels in the plasma and renal cortex was evaluated to reflect the sympathetic activity. The expressions of leptin receptor (LepRb) mRNA, phosphorylated signal transducer and activator of transcription-3 (p-STAT3), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), suppressor of cytokine signaling 3 (SOCS3) mRNA, and protein-tyrosine phosphatase 1B (PTP1B) mRNA, pro-opiomelanocortin (POMC) mRNA and neuropeptide Y (NPY) mRNA were measured by Western blot or qRT-PCR to evaluate the hypothalamic leptin sensitivity. Additionally, we measured the protein or mRNA levels of ${\alpha}7nAChR$, inhibitor of nuclear factor ${\kappa}B$ kinase subunit ${\beta}/nuclear$ factor ${\kappa}B$ ($IKK{\beta}/NF-KB$) and pro-inflammatory cytokines ($IL-1{\beta}$ and $TNF-{\alpha}$) in hypothalamus and adipose tissue to reflect the anti-inflammatory effects of As IV through upregulating expression of ${\alpha}7nAChR$. We found that As IV prevented body weight gain and adipose accumulation, and also improved metabolic disorders in HFD rats. Furthermore, As IV decreased BP and HR, as well as NE levels in blood and renal tissue. In the hypothalamus, As IV alleviated leptin resistance as evidenced by the increased p-STAT3, LepRb mRNA and POMC mRNA, and decreased p-PI3K, SOCS3 mRNA, and PTP1B mRNA. The effects of As IV on leptin sensitivity were related in part to the up-regulated ${\alpha}7nAchR$ and suppressed $IKK{\beta}/NF-KB$ signaling and pro-inflammatory cytokines in the hypothalamus and adipose tissue, since co-administration of ${\alpha}7nAChR$ selective antagonist ${\alpha}-BGT$ could weaken the improved effect of As IV on central leptin resistance. Our study suggested that As IV could efficiently prevent obesityassociated hypertension through inhibiting inflammatory reaction and improving leptin resistance; furthermore, these effects of As IV was partly related to the increased ${\alpha}7nAchR$ expression.