Intermittent hypoxic preconditioning relieves fear and anxiety behavior in post-traumatic stress model mice / 生理学报

Intermittent hypoxia (IH) has preventive and therapeutic effects on hypertension, myocardial infarction, cerebral ischemia and depression, but its effect on post-traumatic stress disorder (PTSD) has not been known. In this study, we used inescapable electric foot shock combined with context recapture to build PTSD mouse model. The levels of fear and anxiety were valued by the open field, the elevated plus maze (EPM) and the fear conditioning tests; the level of spatial memory was valued by Y maze test; the number of Fos positive neurons in hippocampus, amygdala and medial prefrontal cortex was valued by immunohistochemical staining; and the protein expressions of hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and brain derived neurotrophic factor (BDNF) in these brain area were valued by Western blot. The results showed that IH and model (foot shock) had an interaction on percentage of entering open arms (OE%) in EPM and freezing time and the number of fecal pellets in fear conditioning test. IH increased OE% in EPM and reduced the freezing time and the number of fecal pellets in fear conditioning test in PTSD model mice. At the same time, IH reduced the number of Fos positive neurons in the hippocampus, amygdala and medial prefrontal cortex of PTSD model mice, and increased the protein expression levels of HIF-1α, VEGF and BDNF in these brain tissues. In conclusion, IH pretreatment can relieve fear and anxiety behavior in post-traumatic stress model mice, suggesting that IH may be an effective means of preventing PTSD.

Changes of regulatory T cells and FoxP3 gene expression in the aging process and its relationship with lung tumors in humans and mice / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Immunosuppressive regulatory T cells (Tregs) participate in tumor immune evasion and the number and suppressive function of Tregs change with the aging process, but it is not clear whether such change leads to a higher incidence of tumors in the elderly. To this end, we designed experiments to explore the changes of Tregs and the functional gene Forkhead box P3 (FoxP3) in the aging process and its relationship with lung tumors in humans and mice.</p><p><b>METHODS</b>The percentage of CD4(+)CD25(+)CD127(low) Tregs and expression of FoxP3 mRNA were analyzed using flow cytometry (FCM) and real-time fluorescence-based quantitative polymerase chain reaction (FQ-PCR). Markers were analyzed in the peripheral blood (PB) of 65 elderly patients (age ≥ 65 years) with primary non-small cell lung cancer (NSCLC), 20 younger patients (aged < 55 years) with NSCLC, 30 elderly healthy individuals and 30 young healthy individuals. Furthermore, we set up the Lewis lung cancer model with C57BL/6 female mice. Thirty-six mice were divided into a young healthy group, a middle-aged healthy group, an elderly healthy group, a young tumor group, a middle-aged tumor group, and an elderly tumor group. The percentage of CD4(+)CD25(+)FoxP3(+) Tregs and the expression level of FoxP3 mRNA in splenocytes were determined in the six groups.</p><p><b>RESULTS</b>The percentage of peripheral CD4(+)CD25(+)CD127(low) Tregs and the expression of FoxP3 mRNA were significantly increased in elderly patients with NSCLC comparing with the other groups and in elderly healthy individuals compared with young healthy individuals. Further analysis showed that the percentage of CD4(+)CD25(+)CD127(low) Tregs and the expression of FoxP3 mRNA were closely associated with tumor node metastasis (TNM) staging in elderly patients with NSCLC. In the mouse model, the percentage of CD4(+)CD25(+)FoxP3(+) Tregs and the expression of FoxP3 mRNA in splenocytes of the tumor groups were significantly higher than in the healthy groups, with the highest expression in the elderly tumor group. In the healthy groups, the elderly healthy mice had the highest percentage of Tregs and expression of FoxP3 mRNA. The elderly mice had larger and heavier tumors than did the young and middle aged mice.</p><p><b>CONCLUSIONS</b>The up-regulation of Tregs and the FoxP3 gene with aging may play an essential role in oncogenesis and development of lung tumors in an elderly population.</p>

Altered CD28 and CD95 mRNA expression in peripheral blood mononuclear cells from elderly patients with primary non-small cell lung cancer / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The expression of the co-stimulatory molecule CD28 and death receptor CD95 on T cells, which change with age, are considered as important immunological parameters of immunosenescence. It is well established that CD28 and CD95 are associated with tumorgenesis and tumor progression, but the relationship between the age-related changes of these two immunological markers and cancer in the elderly is largely unknown.</p><p><b>METHODS</b>The levels of CD28 and CD95 mRNA in peripheral blood mononuclear cells (PBMCs) from sixty-three elderly patients (aged > or = 60 years) with primary non-small cell lung cancer (NSCLC) were analyzed by real-time fluorescence-based quantitative polymerase chain reaction (FQ-PCR). In addition, twenty young patients (aged < 60 years) with NSCLC, thirty elderly healthy donors and thirty young healthy donors were enrolled as controls.</p><p><b>RESULTS</b>CD28 mRNA levels were significantly lower and CD95 mRNA levels were significantly higher in elderly patients with NSCLC than in the other groups. Similar results were found in elderly healthy donors comparing with young healthy donors. By Logistic regression analysis an increased risk of NSCLC was markedly associated with aging, down-regulation of CD28 mRNA and up-regulation of CD95 mRNA, and CD28 mRNA had an obvious negative correlation with the CD95 mRNA. In addition, the mRNA levels of CD28 and CD95 in the peripheral blood of the elderly patients was closely associated with the tumor node metastasis (TNM) stages, grade of cell differentiation and lymph node metastasis status, but not related to pathological types.</p><p><b>CONCLUSIONS</b>The results suggest a close relationship between T cell senescence and NSCLC tumour progress in the elderly, and that up-regulation of CD28 mRNA or down-regulation of CD95 mRNA in peripheral blood T cells may play an important role in inhibiting oncogenesis and development of primary NSCLC in the elderly.</p>