Oxytocin involves in chronic stress-evoked melanoma metastasis via ß-arrestin 2-mediated ERK signaling pathway.

Stress is associated with an increased risk of lung metastasis in melanoma. However, the underlying mechanism is elusive. Oxytocin (OXT), a neurohormone produced by the hypothalamus, plays a vital role in laboring induction and lactation. Emerging evidence suggests that OXT also regulates human emotions, social cognition, social behaviors and stress-related disorders. Here, we reported that a significant up-regulation of oxytocin receptors (OXTRs) was observed in malignant melanoma. The activation of OXTRs dramatically promoted migration, invasion and angiogenesis but not the proliferation of melanoma cells in vitro and in vivo via ß-arrestin 2-dependent ERK-VEGF/MMP-2 pathway. Next, chronic restraint stress significantly elevated the plasma level of OXT. Notably, 21 days chronic restraint stress facilitated lung metastasis of melanoma and reduced overall survival in mice, which were largely abrogated by knocking down either OXTR or ß-arrestin 2. These findings provide evidence that chronic stress hormone-OXT promotes lung metastasis of melanoma via a ß-arrestin 2-dependent mechanism and suggest that OXT, a novel pro-metastasis factor, is a potential therapeutic target for melanoma.

Intranasal oxytocin administration improves depression-like behaviors in adult rats that experienced neonatal maternal deprivation.

Oxytocin (OT), a hypothalamic neuropeptide, has been implicated in the regulation of social behaviors in rodents and humans. This study assessed the effects of intranasal administration of OT on depressive-like behaviors and hippocampal neurogenesis in adult rats following neonatal maternal deprivation (NMD). Here, we show that NMD resulted in significant depression-like behaviors, as indicated by decreases in physical activity and emotional reactivity in a novel environment, in 2-month-old animals. Notably, the OT levels in the plasma, hypothalamus, and hippocampus were decreased in these animals. Intranasal administration of OT reduced the depressive-like behaviors in NMD rats and rescued hippocampal long-term plasticity impaired by NMD stress in rats by promoting hippocampal neurogenesis. These results indicate that OT alleviates the depressive-like behaviors in NMD adult rats, probably mediated by improving adult hippocampal neurogenesis.

The association between psychological strains and life satisfaction: Evidence from medical staff in China.

BACKGROUND: Previous research on the relationship between life satisfaction and its influencing factors has mainly focused on the work domain. Psychological strains, which result from these stress-related outcomes, have not been paid enough attention to explain how it correlates negatively with life satisfaction. METHOD: A cross-sectional study was conducted, using questionnaires sent to selected medical staff in a public hospital in Shandong, China (N = 1012). Multiple regression analysis was used to investigate how psychological strains influencing life satisfactions among medical staff. RESULTS: The findings indicate that aspiration strain and deprivation strain have significantly negative impact on medical staff's life satisfaction even with other variables controlled for. Weekly working hour was a significant predictor for life satisfaction. Family factors, such as marital status and kids in the family as well as social support were important factors in influencing individuals' life satisfaction. CONCLUSION: The current study highlights the negative associations between aspiration strain, deprivation strain and life satisfaction. The result underlines the importance of actions taken to prevent and combat psychological strains. It also provides some evidence for policy makers to improve the work environment for medical staff, such as reduce weekly working hours and enhance social support in order to increase medical staff's life satisfaction.

Psychological strains, depressive symptoms, and suicidal ideation among medical and non-medical staff in urban china.

BACKGROUND: The Strain Theory of Suicide has been tested and well supported regarding rural people who show risk of suicide. Studies on the impact of psychological strains on psychopathologies and suicidality in urban environments in China have been lacking. AIMS: This study was designed to further examine the associations between psychological strains, depressive symptoms, and suicidal ideation in two separate urban samples of adults in China. METHODS: One sample consisted of randomly selected medical employees of a large hospital (n = 1012), and a second sample included heterogeneous office employees (n = 1052). A self-administered questionnaire was used to collect demographics, psychological strains, social support, depressive symptoms, and suicidal ideation. RESULTS: Depressive symptoms were associated with longer work hours, less social support, value strain, aspiration strain and coping strain among medical staff, and were linked to longer work hours, less social support, aspiration strain and coping strain among non-medical staff. Suicide ideation was associated with longer work hours, coping strain, and depression among medical staff, and was linked to longer work hours, gender, religion, value strain and depression among non-medical staff. CONCLUSIONS: Both depressive symptoms and suicidal ideation were associated with psychological strains among Chinese urban professionals. Reduction of psychological strain is necessary to help maintain proper mental health and to ensure optimal performance at work.

Oxytocin inhibits ovarian cancer metastasis by repressing the expression of MMP-2 and VEGF.

Breastfeeding is associated with a decreased risk of ovarian cancer. However, the mechanism underlying this apparent clinical benefit is unknown. Oxytocin (OXT), a hypothalamic nonapetide, plays a crucial role in many reproductive and behavioural functions. In recent year, OXT acts as a growth regulator in many kind of tumor tissues, through the activation of a specific G-coupled transmembrane receptor, the oxytocin receptor (OXTR). OXT has been proved to inhibit the proliferation, migration and invasion of ovarian cancer SKOV3 cells in vitro. But, the underlying mechanisms remain unknown. Here, we found OXT inhibited proliferation, and critically migration and invasion of human ovarian cancer cells SKOV3 and A2780. Strikingly, OXT inhibited ovarian cancer metastasis by repressing the expressions of MMP-2 and VEGF. Moreover, OXT inhibited vascular endothelial cell tube formation by reducing the VEGF production from ovarian cancer cells. Our findings may provide a possible explanation for breastfeeding-associated protective effects and suggest new therapeutic opportunities for ovarian cancer.