APPROACH AND RESULTS: Human atherosclerotic plaques showed marked mitochondrial dysfunction, manifested as reduced mtDNA copy number and oxygen consumption rate in fibrous cap and core regions. Vascular smooth muscle cells derived from plaques showed impaired mitochondrial respiration, reduced complex I expression, and increased mitophagy, which was induced by oxidized low-density lipoprotein. Apolipoprotein E-deficient (ApoE-/-) mice showed decreased mtDNA integrity and mitochondrial respiration, associated with increased mitochondrial reactive oxygen species. To determine whether alleviating mtDNA damage and increasing mitochondrial respiration affects atherogenesis, we studied ApoE-/- mice overexpressing the mitochondrial helicase Twinkle (Tw+/ApoE-/-). Tw+/ApoE-/- mice showed increased mtDNA integrity, copy number, respiratory complex abundance, and respiration. Tw+/ApoE-/- mice had decreased necrotic core and increased fibrous cap areas, and Tw+/ApoE-/- bone marrow transplantation also reduced core areas. Twinkle increased vascular smooth muscle cell mtDNA integrity and respiration. Twinkle also promoted vascular smooth muscle cell proliferation and protected both vascular smooth muscle cells and macrophages from oxidative stress-induced apoptosis.
CONCLUSIONS: Endogenous mtDNA damage in mouse and human atherosclerosis is associated with significantly reduced mitochondrial respiration. Reducing mtDNA damage and increasing mitochondrial respiration decrease necrotic core and increase fibrous cap areas independently of changes in reactive oxygen species and may be a promising therapeutic strategy in atherosclerosis.
RESULTS: Our findings showed that in vivo model of C. neoformans infection demonstrated induction of abundant IL-17A secretion. By examining the lung bronchoalveolar lavage fluid (BALF), mediastinal lymph node (mLN) and spleen of the IL-17A-EGFP reporter mice, we showed that intranasal inoculation with C. neoformans promoted leukocytes lung infiltration. A large proportion (~ 50%) of the infiltrated CD4+ helper T cell population secreted EGFP, indicating vigorous TH17 activity in the C. neoformans-infected lung. The infection study in IL-17A-KO mice, on the other hand, revealed that absence of IL-17A marginally boosted fungal burden in the lung and accelerated the mouse death.
CONCLUSION: Therefore, our data suggest that IL-17A is released predominantly from TH17 cells in vivo, which plays a supporting role in the protective immunity against C. neoformans infection.
Methods: LMs were obtained and incubated with mature BMDCs. The internalization of LMs by BMDCs was studied by confocal microscopy, and the LMs immune-stimulatory capacity was determined by the expression of surface molecules (CD86 and MHCII) and the cytokine production (interleukin [IL]-12, interferon-Υ, tumor necrosis factor-α, and IL-10) 24 h after exposure to LMs.
Results: The interaction of LMs with BMDCs and its internalization was demonstrated as well as the immune activation of BMDCs, characterized by the increased expression of CD86 and the production of IL-12. The LMs internalization and immune activation of BMDCs were blocked in the presence of cytochalasin, filipin III and chlorpromazine, which demonstrated that internalization of LMs by BMDCs is a key process for the LMs induced immune activation of BMDCs.
Conclusions: The results obtained support the further evaluation of LMs as a mycobacterial vaccine, adjuvant, and in immunotherapy.
AIMS: The objectives of this study were to determine the effects of khat and its active alkaloid, cathinone, on food intake and body weight in mice maintained on a high-fat diet, and to investigate its mechanism of action in white adipose tissue and in the hypothalamus.
MATERIALS & METHOD: Adult male mice (C57BL/6J) were fed a high fat diet (HFD) for 8 weeks (n = 30), then divided into 5 groups and treated daily for a further 8 weeks with HFD + vehicle [control (HFD)], HFD + 15 mg/kg orlistat (HFDO), HFD + 200 mg/kg khat extract (HFDK200), HFD + 400 mg/kg khat extract (HFDK400) and HFD + 3.2 mg/kg cathinone (HFDCAT). Treatments were carried out once daily by gastric gavage. Blood and tissue samples were collected for biochemical, hormonal and gene expression analyses.
RESULTS: Khat extracts and orlistat treatment significantly reduced weight gain as compared to control mice on HFD, and cathinone administration completely prevented weight gain in mice fed on HFD. Khat treatment caused a marked reduction in body fat and in serum triglycerides. A dose-dependent effect of khat was observed in reducing serum leptin concentrations. Analysis of gene expression in adipose tissue revealed a significant upregulation of two lipolysis pathway genes:(adipose triglyceride lipase (PNPLA-2) and hormone-sensitive lipase (LIPE). In the hypothalamic there was a significant (P mice on an obesogenic diet through stimulation of lipolysis in white adipose tissue.
METHODS: per-orally infected C57BL/6 mice with 15-20 cysts of the avirulent T. gondii Beverly strain at 9-11 weeks of age were examined 12 weeks later during parasite establishment. Distributions of the parasite's cysts and the histopathological lesions in the brains were analyzed using Image J software. Relative expression of TNF-α and iNOS of cell-mediated immunity (CMI), Bax (pro-apoptosis) and Bcl-2 (anti-apoptosis) were all assessed using immunohistochemistry.
RESULTS: higher parasite burden was seen in the forebrain with p value <= 0.05. Dramatically increased TNF-α, iNOS, and Bax expressions with Bax/Bcl-2 ratio 2.42:0.52 were reported (p value <= 0.05). The significant correlation between Bax data and different CMI biomarkers including TNF-α and i-NOS was evaluated. Interestingly, no significant correlation was seen between TNF-α, iNOS, Bax and Bcl-2 expressions and location of the parasite. However, Bax/Bcl-2 ratio was statistically correlated with CMI biomarkers and whole sample mean parasite burden, p value <= 0.05.
CONCLUSION: Chronic toxoplasmosis exhibits an immense pro-apoptotic signal on the cerebral tissues of experimental mice.