Increasing evidence suggests that stress may induce changes in hair color, with the underlying mechanism incompletely understood. In this study, female C57BL/6 mice subjected to electric foot shock combined with restraint stress were used to build chronic stress mouse model. The melanin contents and tyrosinase activity were measured in mouse skin and B16F10 melanoma cells. The enzyme-linked immunosorbent assay (ELISA) was used to determine the content of tumor necrosis factor α (TNF-α), interleukin- 1β (IL-1β) and interleukin-6 (IL-6) in the mouse skin. The content of nuclear factor κB (NFκB)/p65 subunit in mouse skins was valued by immunofluorescence staining. The results demonstrated that under chronic stress, the fur color turned from dark to brown in C57BL/6 mice due to the decrease of follicle melanocytes and tyrosinase activity in C57BL/6 mouse skin. Simultaneously, inflammatory responses in skins were detected as shown by increased NFκB activity and TNF-α expression in stressed mouse skin. In cultured B16F10 melanoma cells, TNF-α reduced the melanogenesis and tyrosinase activity in a dose-dependent manner. These findings indicate that chronic stress induces fur color change by decreasing follicle melanocytes and tyrosinase activity in female C57BL/6 mice, and TNF-α may play an important role in stress-induced hair color change.
Animal Fur ; Animals ; Color ; Female ; Melanins ; Melanocytes ; enzymology ; Melanoma, Experimental ; Mice ; Mice, Inbred C57BL ; Monophenol Monooxygenase ; metabolism ; Pigmentation ; Skin ; physiopathology ; Stress, Physiological

The pathophysiology of visceral pain in patients with irritable bowel syndrome remains largely unknown. Our previous study showed that neonatal maternal deprivation (NMD) does not induce visceral hypersensitivity at the age of 6 weeks in rats. The aim of this study was to determine whether NMD followed by adult stress at the age of 6 weeks induces visceral pain in rats and to investigate the roles of adrenergic signaling in visceral pain. Here we showed that NMD rats exhibited visceral hypersensitivity 6 h and 24 h after the termination of adult multiple stressors (AMSs). The plasma level of norepinephrine was significantly increased in NMD rats after AMSs. Whole-cell patch-clamp recording showed that the excitability of dorsal root ganglion (DRG) neurons from NMD rats with AMSs was remarkably increased. The expression of β adrenergic receptors at the protein and mRNA levels was markedly higher in NMD rats with AMSs than in rats with NMD alone. Inhibition of β adrenergic receptors with propranolol or butoxamine enhanced the colorectal distention threshold and application of butoxamine also reversed the enhanced hypersensitivity of DRG neurons. Overall, our data demonstrate that AMS induces visceral hypersensitivity in NMD rats, in part due to enhanced NE-β adrenergic signaling in DRGs.
Adrenergic Agents ; pharmacology ; Animals ; Ganglia, Spinal ; drug effects ; Hyperalgesia ; drug therapy ; physiopathology ; Hypersensitivity ; drug therapy ; Male ; Maternal Deprivation ; Neurons ; drug effects ; Patch-Clamp Techniques ; methods ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Stress, Physiological ; physiology ; Visceral Pain ; chemically induced ; metabolism

Restraint water-immersion stress (RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala (CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress (RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition, RWIS, but not RS, induced the activation of corticotropin-releasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers. This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.
Action Potentials ; drug effects ; physiology ; Analysis of Variance ; Animals ; Central Amygdaloid Nucleus ; pathology ; Corticotropin-Releasing Hormone ; metabolism ; Disease Models, Animal ; Gastric Mucosa ; pathology ; Gene Expression Regulation ; physiology ; Neurons ; physiology ; Patch-Clamp Techniques ; Proto-Oncogene Proteins c-fos ; metabolism ; Rats ; Rats, Wistar ; Stress, Physiological ; physiology ; Stress, Psychological ; etiology ; physiopathology

Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized mainly by motor dysfunction resulting in bradykinesia, rigidity, tremor, gait impairment, and postural instability. The classic pathogenic feature of PD is preferential loss of dopaminergic neurons in the substantia nigra. Downregulation of rRNA transcription is one of major mechanisms to maintain cellular homeostasis under stress conditions. Nucleolar stress has emerged as a component of the degenerative process caused by impaired rRNA transcription and altered nucleolar integrity. Recent study has indicated that the response to stress conditions and quality control mechanisms are impaired in PD, and that metabolic stress may be a trigger mechanism for PD. This review aims to present evidence for a role of nucleolar stress in PD and has summarized mechanisms by which nucleolar stress may play a role in the progression of PD.
Cell Nucleolus ; physiology ; Humans ; Parkinson Disease ; etiology ; physiopathology ; RNA, Ribosomal ; genetics ; Signal Transduction ; Stress, Physiological ; TOR Serine-Threonine Kinases ; physiology

BACKGROUNDThis study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events (SLEs) before the onset of depression.

METHODSForty-three drug-naive female patients voluntarily participated in the present study after the first major depressive episode. The life event scale was used to evaluate the severity of the impact of SLEs during 6 months before the onset of the major depressive episode. High-field magnetic resonance imaging (MRI) scans were obtained, and the VBM and SPM8 software process were used to process and analyze the MRI.

RESULTSCompared to that in patients without SLEs, the volume of brain gray matter was lower in the bilateral temporal lobe, right occipital lobe, and right limbic lobe in the SLE group. However, the gray matter volume did not differ significantly between the two groups after the application of false discovery rate (FDR) correction.

CONCLUSIONSAlthough the results of the present study suggest the absence of significant differences in brain gray matter volume between female drug-naive patients after the first episode of major depression with and without SLEs after FDR correction, the study provides useful information for exploring the definitive role of stress in the onset of depression.

Adolescent ; Adult ; Depression ; physiopathology ; Female ; Gray Matter ; anatomy & histology ; Humans ; Magnetic Resonance Imaging ; Middle Aged ; Software ; Stress, Physiological ; physiology ; Young Adult

OBJECTIVETo investigate the clinical value of Physiologic Ability and Surgical Stress (E-PASS) and modified Estimation of Physiologic Ability and Surgical Stress (mE-PASS) scoring systems in predicting the mortality and surgical risk of gastric cancer patients, and to analyze the relationship between the parameters of E-PASS and early postoperative complications.

METHODSClinical data of 778 gastric cancer patients who underwent elective surgical resection in Tianjin Medical University General Hospital from Jan. 2010 to Jan. 2014 were analyzed retrospectively. E-PASS and mE-PASS scoring systems were used to predict the mortality of gastric cancer patients, respectively. Univariate and unconditioned logistic regression analyses were performed to assess the relationships between nine parameters of E-PASS system and early postoperative complications.

RESULTSE-PASS and mE-PASS systems were used to predict the mortality in the death group and non-death group. The Z value was -5.067 and -4.492, respectively, showing a significant difference between the two groups (P<0.05). AUCs of mortality predicted by E-PASS and mE-PASS were 0.926 and 0.878 (P>0.05), and the prediction calibration of postoperative mortality showed statistically non-significant difference (P>0.05) between the E-PASS and mE-PASS prediction and actual mortality. Univariate analysis showed that age, operation time, severe heart disease, severe lung disease, diabetes mellitus, physical state index and ASA classification score are related to postoperative complications (P<0.05 for all). Unconditioned logistic regression analysis showed that severe lung disease, diabetes mellitus, ASA classification score and operation time are risk factors for early postoperative complications (P<0.05 for all).

CONCLUSIONSBoth mE-PASS and E-PASS scoring system have good consistency in the predicting postoperative mortality and actual mortality, and both are suitable for clinical application. Moreover, the mE-PASS scoring system is clinically more simple and convenient than E-PASS scoring system. Preoperative severe lung disease, diabetes mellitus, ASA classification score and operation time are independent factors affecting the early postoperative complications.

Age Factors ; Area Under Curve ; Diabetes Complications ; Elective Surgical Procedures ; Homeostasis ; Humans ; Lung Diseases ; complications ; Operative Time ; Postoperative Complications ; etiology ; mortality ; Postoperative Period ; Predictive Value of Tests ; Regression Analysis ; Retrospective Studies ; Risk Assessment ; methods ; Risk Factors ; Stomach Neoplasms ; mortality ; physiopathology ; surgery ; Stress, Physiological

This study was aimed to investigate the effect of stress induced by high-intensity exercises on the cardiovascular system. In the epidemiological investigation, 200 subjects (test group) engaged in special high-intensity exercises, and 97 who lived and worked in the same environment and conditions as those in the test group, but did not participate in the exercises served as controls. In the second part of the study, 50 mice were randomly divided into control group, exhaustive swimming group, white noise group, exhaustive swimming plus white noise group, and pioglitazone intervention group. The results showed that the plasma concentrations of the myocardial injury markers heart fatty acid-binding protein (H-FABP), C-reactive protein (CRP), β-endorphin (β-EP) and levels of psychological stress were significantly increased in test group as compared with control group; special high-intensity exercises resulted in a significant elevation of the incidence of cardiac arrhythmias. Animal experiments showed that the plasma levels of corticosterone (CORT) and troponin I (TnI) were raised while the level of SOD was reduced in exhaustive swimming group, white noise group, and exhaustive swimming plus white noise group. The expression levels of PPARγ mRNA and protein were decreased in myocardial tissues in these groups as well. HE staining showed no remarkable change in myocardial tissues in all the groups. Treatment with pioglitazone significantly decreased the plasma levels of TnI and CORT, while increased the level of SOD and the expression levels of PPARγ mRNA and protein. It was concluded that the high-intensity exercises may induce a heavy physical and psychological stress and predispose the subjects to accumulated fatigue and sleep deprivation; high-intensity exercises also increases the incidence of arrhythmias and myocardial injury. PPARγ may be involved in the physical and psychological changes induced by high-intensity exercises.
Animals ; Heart Injuries ; physiopathology ; Male ; Mice ; PPAR gamma ; genetics ; physiology ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction ; Stress, Physiological

OBJECTIVETo evaluate the effects of prenatal stress on neurological functions after middle cerebral artery occlusion (MCAO) in adult offspring rats.

METHODSPregnant rats were randomly assigned to prenatal stress treatment, which was exposed to restraint three times daily in the last week of pregnancy, and no prenatal stress treatment. Adult male offspring rats were subjected to transient focal cerebral ischemia by MCAO. They were randomly divided into four groups: sham group, prenatal stress + sham group, MCAO group and prenatal stress + MCAO group (n = 10). After 24 hours of reperfusion, the neurological deficits were evaluated. The infarct size, cell apoptosis and expression of Caspase 3, cleaved Caspase 3 and Bcl-2 were detected.

RESULTSCompared with MCAO group, the neurological deficits, infarct size and apoptotic cells in prenatal stress + MCAO group were increased significantly (all P < 0.05). The expressions of Caspase 3 and cleaved Caspase 3 were much greater in prenatal stress + MCAO group than those of MCAO group, while the expression of Bcl-2 was significantly decreased in prenatal stress + MCAO group compared with MCAO group (all P < 0.05).

CONCLUSIONPrenatal stress might exacerbate neuroloeical deficits in the offspring rats after MCAO by increasing cell apoptosis.

Animals ; Apoptosis ; Caspase 3 ; metabolism ; Female ; Infarction, Middle Cerebral Artery ; physiopathology ; Ischemic Attack, Transient ; physiopathology ; Male ; Pregnancy ; Prenatal Exposure Delayed Effects ; physiopathology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Stress, Physiological

The present study was designed to investigate the potential role of endogenous hydrogen sulfide (H2S) in chronic stress-induced colonic hypermotility. Male Wistar rats were submitted daily to 1 h of water avoidance stress (WAS) or sham WAS (SWAS) for 10 consecutive days. The total number of fecal pellets was counted at the end of each 1 h of WAS or SWAS session. Organ bath recordings were used to test the colonic motility. H₂S production of colon was determined, and immunohistochemistry and Western blot were performed on rat colonic samples to detect the distribution and expression of H₂S-producing enzymes. The results showed that i) repeated WAS increased the number of fecal pellets per hour and the area under the curve (AUC) of the spontaneous contractions of colonic strips (P < 0.05), ii) repeated WAS decreased the endogenous production of H₂S and the expression of H₂S-producing enzymes in the colon devoid of mucosa and submucosa (P < 0.001), iii) cystathionine-γ-lyase (CSE) was strongly expressed in the cytosols of the circular and longitudinal smooth muscle cells and the nucleus of the myenteric plexus neurons, iv) cystathionine-β-synthase (CBS) was primarily localized in the cytosols of myenteric plexus neurons and weakly localized in the epithelial cells and v) inhibitors of H₂S-producing enzymes increased the contractile activity of colonic strips in the SWAS rats (P < 0.001). In conclusion, the results suggest that the colonic hypermotility induced by repeated WAS may be associated with the decreased production of endogenous H2S.
Animals ; Colon ; physiopathology ; Cystathionine beta-Synthase ; metabolism ; Cystathionine gamma-Lyase ; metabolism ; Gastrointestinal Motility ; Hydrogen Sulfide ; metabolism ; Male ; Muscle Contraction ; Myocytes, Smooth Muscle ; metabolism ; Neurons ; metabolism ; Rats ; Rats, Wistar ; Stress, Physiological

OBJECTIVETo clarify drug properties of components in Euodiae Fructus.

METHODThe rat cold syndrome model was induced by cold water stress method. The content of neurotransmitters sand hormones such as DA, 5-HT, NE, AChE and 17-OHCS in serum of model rats were taken as the indexes to evaluate drug properties of components in Euodiae Fructus.

RESULTEuodiae Fructus and its components could correct or relief the content of energy metabolism and substance metabolism-related neurotransmitters sand hormones in serum of model rats with water-stressed cold syndrome.

CONCLUSIONEuodiae Fructus and its components are proved to show hot property.

Animals ; Cold Temperature ; adverse effects ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Gastric Mucosa ; drug effects ; pathology ; Male ; Medicine, Chinese Traditional ; Neurotransmitter Agents ; blood ; Rats ; Rats, Wistar ; Stomach Ulcer ; blood ; drug therapy ; physiopathology ; Stress, Physiological