α-Galactosylceramide and its analog OCH differentially affect the pathogenesis of ISO-induced cardiac injury in mice.

Immunotherapies for cancers may cause severe and life-threatening cardiotoxicities. The underlying mechanisms are complex and largely elusive. Currently, there are several ongoing clinical trials based on the use of activated invariant natural killer T (iNKT) cells. The potential cardiotoxicity commonly associated with this particular immunotherapy has yet been carefully evaluated. The present study aims to determine the effect of activated iNKT cells on normal and ß-adrenergic agonist (isoproterenol, ISO)-stimulated hearts. Mice were treated with iNKT stimulants, α-galactosylceramide (αGC) or its analog OCH, respectively, to determine their effect on ISO-induced cardiac injury. We showed that administration of αGC (activating both T helper type 1 (Th1)- and T helper type 2 (Th2)-liked iNKT cells) significantly accelerated the progressive cardiac injury, leading to enhanced cardiac hypertrophy and cardiac fibrosis with prominent increases in collagen deposition and TGF-ß1, IL-6, and alpha smooth muscle actin expression. In contrast to αGC, OCH (mainly activating Th2-liked iNKT cells) significantly attenuated the progression of cardiac injury and cardiac inflammation induced by repeated infusion of ISO. Flow cytometry analysis revealed that αGC promoted inflammatory macrophage infiltration in the heart, while OCH was able to restrain the infiltration. In vitro coculture of αGC- or OCH-pretreated primary peritoneal macrophages with primary cardiac fibroblasts confirmed the profibrotic effect of αGC and the antifibrotic effect of OCH. Our results demonstrate that activating both Th1- and Th2-liked iNKT cells is cardiotoxic, while activating Th2-liked iNKT cells is likely cardiac protective, which has implied key differences among subpopulations of iNKT cells in their response to cardiac pathological stimulation.

Protective Effects of the Ethanol Extract of Viola tianshanica Maxim against Acute Lung Injury Induced by Lipopolysaccharides in Mice.

Viola tianshanica Maxim, belonging to the Violaceae plant family, is traditionally used in Uighur medicine for treating pneumonia, headache, and fever. There is, however, a lack of basic understanding of its pharmacological activities. This study was designed to observe the effects of the ethanol extract (TSM) from Viola tianshanica Maxim on the inflammation response in acute lung injury (ALI) induced by LPS and the possible underlying mechanisms. We found that TSM (200 and 500 mg/kg) significantly decreased inflammatory cytokine production and the number of inflammatory cells, including macrophages and neutrophils, in bronchoalveolar lavage fluid. TSM also markedly inhibited the lung wet-to-dry ratio and alleviated pathological changes in lung tissues. In vitro, after TSM (12.5-100 µg/ml) treatment to RAW 264.7 cells for 1 h, LPS (1 µg/ml) was added and the cells were further incubated for 24 h. TSM dose-dependently inhibited the levels of proinflammatory cytokines, such as NO, PGE2, TNF-α, IL-6, and IL-1ß, and remarkably decreased the protein and mRNA expression of TNF-α and IL-6 in LPS-stimulated RAW 264.7 cells. TSM also suppressed protein expression of p-IκBa and p-ERK1/2 and blocked nuclear translocation of NF-κB p65. The results indicate that TSM exerts anti-inflammatory effects related with inhibition on NF-κB and MAPK (p-ERK1/2) signaling pathways. In conclusion, our data demonstrate that TSM might be a potential agent for the treatment of ALI.

Actinomycin D synergistically enhances the cytotoxicity of CDDP on KB cells by activating P53 via decreasing P53-MDM2 complex.

The aim of this study is to investigate the synergism of low dose of actinomycin D (LDActD) to the cytotoxicity of cisplatin (CDDP) on KB cells. The role of P53 reactivation by LDActD in the synergism and its mechanism were further studied. Cell viability was determined by MTT assay. Apoptosis was determined by AnnexinV-FITC/PI staining. Mitochondrial membrane potential (MMP) was detected by JC-1 staining. Expression of proteins was detected by Western blotting (WB) and/or immunofluorescence (IF). Molecular docking of actinomycin D (ACTD) to Mouse double minute 2 homolog (MDM2) and Mouse double minute 2 homolog X (MDMX). MDMX was analyzed by Discovery Studio. The content of P53-MDM2 complex was detected by ELISA assay. The cytotoxicity of CDDP was increased by the combination of LDActD in kinds of cancer cells. Molecular docking showed strong interaction between ACTD and MDM2/MDMX. Meanwhile, LDActD significantly decreased P53-MDM2 complex. Significant increase of the apoptotic activity by the combination therapy in KB cells is P53 upregulated modulator of apoptosis (PUMA) dependent. In addition to the decrease in MMP, LDActD increased P53 regulated protein and decreased BCL-XL in KB cells. LDActD efficiently enhanced the cytotoxicity of CDDP in cancer cells and induced P53-PUMA-dependent and mitochondria-mediated apoptosis in KB cells. The reactivation of P53 was probably achieved by disturbing the interaction of P53 and MDM2/MDMX.