Effects of chronic mild stress (CMS) and imipramine administration, on spleen mononuclear cell proliferative response, serum corticosterone level and brain norepinephrine content in male mice

Background: Salivary glands are affected in acute and chronic stressful conditions. Ocimum basilicum (OB), basil, possesses anxiolytic and antidepressant like effect so this study aimed to evaluate the effect of the chronic unpredictable mild stress (CUMS) on the structure of salivary glands of mice and the efficacy of OB in relieving this effect. Material and Methods: Forty male mice were distributed equally into four groups; the control, CUMS (exposed to the CUMS for 4 weeks), CUMS+Fluoxetine (treated with Fluoxetine after exposure to CUMS), CUMS+OB (treated with OB after exposure to CUMS). Treatments continued for 2 weeks. Behavioral changes and serum corticosterone level were assessed at the end of the experiment. Submandibular and parotid glands were histopathologically examined and stained with anti-alpha smooth muscle actin (ASMA) and anti-brain derived neurotropic factor (BDNF) antibodies. Results: A depressive behavior was observed in mice exposed to the CUMS. Serum corticosterone level significantly increased in these mice compared to the control (130.9±8.8 versus 21.03±2.1, p

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Young-Adult Male Rats’ Vulnerability to Chronic Mild Stress Is Reflected by Anxious-Like instead of Depressive-Like Behaviors

Neuroscience Journal ◽

10.1155/2016/5317242 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Herrera-Pérez José Jaime ◽

Benítez-Coronel Venus ◽

Jiménez-Rubio Graciela ◽

Hernández-Hernández Olivia Tania ◽

Martínez-Mota Lucía

Keyword(s):

Body Weight ◽

Weight Gain ◽

Young Adult ◽

Adult Male ◽

Body Weight Gain ◽

Chronic Mild Stress ◽

Male Rats ◽

Mild Stress ◽

Serum Corticosterone ◽

Plus Maze

In a previous study, we found that chronic mild stress (CMS) paradigm did not induce anhedonia in young-adult male rats but it reduced their body weight gain. These contrasting results encouraged us to explore other indicators of animal’s vulnerability to stress such as anxious-like behaviors, since stress is an etiologic factor also for anxiety. Thus, in this study, we evaluated the vulnerability of these animals to CMS using behavioral tests of depression or anxiety and measuring serum corticosterone. Male Wistar rats were exposed to four weeks of CMS; the animals’ body weight and sucrose preference (indicator of anhedonia) were assessed after three weeks, and, after the fourth week, some animals were evaluated in a behavioral battery (elevated plus maze, defensive burying behavior, and forced swimming tests); meanwhile, others were used to measure serum corticosterone. We found that CMS (1) did not affect sucrose preference, immobility behavior in the forced swimming test, or serum corticosterone; (2) decreased body weight gain; and (3) increased the rat’s entries into closed arms of the plus maze and the cumulative burying behavior. These data indicate that young male rats’ vulnerability to CMS is reflected as poor body weight gain and anxious-like instead of depressive-like behaviors.

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Chronic Mild Stress Causes Bone Loss via an Osteoblast-Specific Glucocorticoid-Dependent Mechanism

Endocrinology ◽

10.1210/en.2016-1658 ◽

2017 ◽

Vol 158 (6) ◽

pp. 1939-1950 ◽

Cited By ~ 5

Author(s):

Holger Henneicke ◽

Jingbao Li ◽

Sarah Kim ◽

Sylvia J. Gasparini ◽

Markus J. Seibel ◽

...

Keyword(s):

Bone Loss ◽

Chronic Stress ◽

Structural Parameters ◽

Chronic Mild Stress ◽

Bone Resorption Marker ◽

Mild Stress ◽

Male Mice ◽

Female Mice ◽

Glucocorticoid Signaling ◽

The Impact

Abstract Chronic stress and depression are associated with alterations in the hypothalamic–pituitary–adrenal signaling cascade and considered a risk factor for bone loss and fractures. However, the mechanisms underlying the association between stress and poor bone health are unclear. Using a transgenic (tg) mouse model in which glucocorticoid signaling is selectively disrupted in mature osteoblasts and osteocytes [11β-hydroxysteroid-dehydrogenase type 2 (HSD2)OB-tg mice], the present study examines the impact of chronic stress on skeletal metabolism and structure. Eight-week-old male and female HSD2OB-tg mice and their wild-type (WT) littermates were exposed to chronic mild stress (CMS) for the duration of 4 weeks. At the endpoint, L3 vertebrae and tibiae were analyzed by micro–computed tomography and histomorphometry, and bone turnover was measured biochemically. Compared with nonstressed controls, exposure to CMS caused an approximately threefold increase in serum corticosterone concentrations in WT and HSD2OB-tg mice of both genders. Compared with controls, CMS resulted in loss of vertebral trabecular bone mass in male WT mice but not in male HSD2OB-tg littermates. Furthermore, both tibial cortical area and area fraction were reduced in stressed WT but not in stressed HSD2OB-tg male mice. Osteoclast activity and bone resorption marker were increased in WT males following CMS, features absent in HSD2OB-tg males. Interestingly, CMS had little effect on vertebral and long-bone structural parameters in female mice. We conclude that in male mice, bone loss during CMS is mediated via enhanced glucocorticoid signaling in osteoblasts (and osteocytes) and subsequent activation of osteoclasts. Female mice appear resistant to the skeletal effects of CMS.

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Ginsenoside Rb1 Induces a Pro-Neurogenic Microglial Phenotype via PPARγ Activation in Male Mice Exposed to Chronic Mild Stress

10.21203/rs.3.rs-269050/v1 ◽

2021 ◽

Author(s):

Zili You ◽

Lijuan Zhang ◽

Minmin Tang ◽

Xiaofang Xie ◽

Qiuying Zhao ◽

...

Keyword(s):

Chronic Mild Stress ◽

Hippocampal Neurogenesis ◽

Adult Hippocampal Neurogenesis ◽

Immunofluorescence Staining ◽

Mild Stress ◽

Ginsenoside Rb1 ◽

Male Mice ◽

Antidepressant Effects

Abstract BackgroundAnti-inflammatory approaches are emerging as a new strategy for treatment of depressive disorders. Ginsenoside Rb1 (GRb1), a major component of Panax ginseng, can inhibit inflammatory cascade and alleviate depressive behaviors. Microglia can promote or inhibit adult hippocampal neurogenesis according to their functional phenotypes. Here, we examined whether GRb1 may exert antidepressant effects by promoting a pro-neurogenic phenotype of microglia and thereby increasing neurogenesis. MethodsThe antidepressant effects of GRb1 or the licensed antidepressant imipramine (IMI) were assessed in chronic mild stress (CMS)-exposed male mice. The depressive-like behaviors of mice were evaluated by sucrose preference test, forced swimming test (FST), and tail suspension test (TST). The microglial phenotypes were identified by molecular markers and morphological properties, analyzed by RT-qPCR, western blotting and immunofluorescence staining. Effect of GRb1-treated microglia on adult hippocampal neurogenesis in vivo and in vitro were detected using immunofluorescence staining. ResultsBehavioral assessment indicated that GRb1 or IMI treatment alleviated depressive-like behaviors in CMS-exposed mice. Immunofluorescence examinationdemonstrated that GRb1 induced a pro-neurogenic phenotype of microglia via activating PPARγ in vivo and in vitro, which were reversed by PPARγ inhibitor GW9662. In addition, GRb1-treated microglia increased the proliferation and differentiation of neural precursor cells.ConclusionsThese findings demonstrated that GRb1 alleviated depressive-like behaviors of CMS-exposed male mice mainly through PPARγ-mediated microglial activation and improvement of adult hippocampus neurogenesis.

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A Comparison of Isolation Stress and Unpredictable Chronic Mild Stress for the Establishment of Mouse Models of Depressive Disorder

Frontiers in Behavioral Neuroscience ◽

10.3389/fnbeh.2020.616389 ◽

2021 ◽

Vol 14 ◽

Author(s):

Jin-Seok Lee ◽

Ji-Yun Kang ◽

Chang-Gue Son

Keyword(s):

Animal Models ◽

Depressive Disorder ◽

Depressive Disorders ◽

Chronic Mild Stress ◽

Tail Suspension Test ◽

Modern Society ◽

Mild Stress ◽

Isolation Stress ◽

Unpredictable Chronic Mild Stress ◽

Serum Corticosterone

This study aimed to help to understand the influence of stress on depression, which reflects the social environments of especially solitary life and the increasing prevalence of depressive disorders. To determine the distinguishable features of two-representative animal models of stress-induced depressive disorder, we compared isolation stress (IS) and unpredictable chronic mild stress (UCMS). After 4-week of stress, both models showed significant depressive- and anxiety-like behaviors in an open field test (OFT; p < 0.01 for IS, p < 0.01 for UCMS), forced swimming test (FST; p < 0.01 for IS, p < 0.01 for UCMS), and tail suspension test (TST; p < 0.01 for IS, p < 0.05 for UCMS) along with alterations in serum corticosterone levels, serotonin activity in the dorsal raphe nuclei (DRN) and microglial activity in the dentate gyrus of the hippocampus (p < 0.05 for both parameters). In a comparison of the two stress models, IS strongly induced depressive and anxiety features, as indicated by all parameters: behavior test scores (p < 0.05 for OFT, FST, and TST), serum corticosterone levels (p < 0.05), immunohistological alterations for serotonin activity (p < 0.05) and microglial activity (p = 0.072). Our results indicate the suitability of IS for the development of animal models of depressive disorders and may reveal the medical impact of social isolation environment in modern society.

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