cytochrome-c-t and Depressive-Disorder--Major

Major depressive disorder (MDD) affects approximately 16% of the global population. Our previous study has demonstrated that icariin (ICA) exhibits anti-depressant activity by increasing the expression of Brain-Derived Neurotrophic Factor (BDNF) in a rat model of chronic unpredictable mild stress (CUMS). In this study, we investigated whether and how ICA can prevent CUMS-induced depression-like behaviors in rats by modulating hippocampus neuronal apoptosis. Forty male rats were randomly divided into control, CUMS, CUMS-fluoxetine (Flx) (10 mg/kg), and CUMS-ICA (20 mg/kg) groups. Behavior tests including sucrose preference test (SPT), open field test (OFT), elevated plus-maze (EPM), and forced swimming tests (FST) were performed. The Nissl staining and TUNNEL assay were used to determine neuronal apoptosis. Subsequently, expression of the glucocorticoid receptor (GR), Bcl-2, cytochrome C, caspase-3 and Bax in the hippocampus was tested by western blot. Our results show that a chronic administration of ICA (20 mg/kg) can prevent CUMS-induced depressant-like behaviors in male model rats. Additionally, ICA significantly inhibited mitochondrial translocation of GR, reduced mitochondrial outer membrane permeabilization (MOMP) to suppress the release of cytochrome C, and then inhibit the activation of caspase-3. In conclusion, our research provides new evidence to understand the anti-depressant activity of ICA, which relates to its inhibition of neuronal apoptosis in the hippocampus through the mitochondrial apoptotic pathway.

Topics: Animals; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Cytochromes c; Cytoplasm; Depressive Disorder, Major; Male; Rats

Fluoxetine (Flx) is the most commonly used antidepressant to treat major depressive disorder. However, its molecular mechanisms of action are not defined as yet. A comparative proteomic approach was used to identify proteome changes in the prefrontal cortex (PFC) cytosolic and non-synaptic mitochondria (NSM)-enriched fractions of adult male Wistar rats following chronic social isolation (CSIS), a rat model of depression, and Flx treatment in CSIS and control rats, using liquid chromatography online tandem mass spectrometry. Flx reversed CSIS-induced depressive - like behavior according to preference for sucrose and immobility in the forced swim test, indicating its antidepressant effect. Flx treatment in controls led to an increase of the expression of cytosolic proteins involved in the microtubule cytoskeleton and intracellular calcium homeostasis and of enzymes involved in bioenergetic and transmembrane transport in NSM. CSIS downregulated the cytosolic proteins involved in proteasome pathway, and glutathione antioxidative system, and upregulated the expression of enzymes participating in mitochondrial-energy metabolism and transport. The presence of cytochrome c in the cytosol may suggest compromised mitochondrial membrane integrity. Flx treatment in CSIS rats downregulated protein involved in oxidative phosphorylation, such as complex III and manganese superoxide dismutase, and upregulated vesicle-mediated transport and synaptic signaling proteins in the cytosol, and neuronal calcium-binding protein 1 in NSM. Our study identified PFC modulated proteins and affected biochemical pathways that may represent potential markers/targets underlying CSIS-induced depression and effective Flx treatment, and highlights the role of protein systems involved in NSM and various metabolic pathways potentially involved in neuronal plasticity.

Topics: Animals; Antidepressive Agents; Calcium; Calcium-Binding Proteins; Cytochromes c; Depression; Depressive Disorder, Major; Electron Transport Complex III; Fluoxetine; Glutathione; Hippocampus; Male; Prefrontal Cortex; Proteasome Endopeptidase Complex; Proteome; Proteomics; Rats; Rats, Wistar; Sucrose; Superoxide Dismutase

Acceleration of blood leukocyte apoptosis in major depression has been described. The present studies have been undertaken to estimate the level of apoptosis of blood leukocytes in patients with depression and to examine the mechanisms leading to apoptosis. Blood was taken from 29 patients with depression (age 48.2+/-11.2, 14 males, 15 females) and 30 healthy controls (age 41.3+/-4.1, 15 males, 15 females), and apoptosis was estimated by the cytometric method by measurements of annexin V binding, mitochondrial membrane potential (DeltaPsi), bcl-2, bax, and Fas (CD95) expression in CD4+, CD8+ and CD14+ cells. The amounts of cytochrome c released from mitochondria to cytosol of peripheral blood mononuclear cells (PBMCs) and polymorphonuclear cells (PMNs) were also measured. The levels of reactive oxygen species (ROS) released from PMNs were examined as was the serum activity of superoxide dismutase (SOD), catalase (CAT), and total peroxidase (PER). Additionally, serum levels of the tumor necrosis factor (TNF-alpha) and interleukin-6 (IL-6) were estimated. Our experiments indicated accelerated apoptosis of CD4+ T lymphocytes and CD14+ cells (mainly neutrophils) of depressed patients as well as a significant increase in the percent of Fas-expressing cells. Bcl-2 and bax expression was higher in cells of depressed patients than in control, however, bcl-2/bax ratio was significantly decreased in CD14+ cells of depressed patients. PMNs isolated from the blood of the patients produced more ROS spontaneously and after induction with phorbol ester (PMA) than PMNs of the healthy control. A significant increase in serum activity of SOD, CAT and PER was also detected. Overproduction of superoxide anion correlated positively with the level of PMNs apoptosis (measured by cytochrome c release), suggesting that superoxide anion might be an important factor inducing apoptotic death of blood cells. The result of our experiment indicated that apoptosis of immune cells may affect patient's susceptibility to different infections and application of antioxidants in medication of patients with depression will be beneficial for them. The increased level of IL-6 in sera of the depressed patients did not correlate with overproduction of ROS, suggesting that this cytokine is not involved in oxidative stress and apoptosis of leukocytes.

Topics: Adult; Analysis of Variance; Apoptosis; bcl-2-Associated X Protein; Catalase; Cytochromes c; Cytokines; Depressive Disorder, Major; fas Receptor; Female; Flow Cytometry; Gene Expression Regulation; Humans; Hydrogen Peroxide; Leukocytes; Male; Middle Aged; Oxidative Stress; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Statistics, Nonparametric; Superoxides