ABSTRACT
Insulin is a secreted peptide hormone identified in human pancreas to promote glucose utilization. Insulin has been observed to induce cell proliferation and myogenesis in C2C12 cells. The precise mechanisms underlying the proliferation of C2C12 cells induced by insulin remain unclear. In this study, we observed for the first time that 10 nM insulin treatment promotes C2C12 cell proliferation. Additionally, 50 and 100 nM insulin treatment induces C2C12 cell apoptosis. By utilizing real-time PCR and Western blotting analysis, we found that the mRNA levels of cyclinD1 and BAD are induced upon 10 and 50 nM/100 nM insulin treatment, respectively. The similar results were observed in C2C12 cells expressing GATA-6 or PPARα. Our results identify for the first time the downstream targets of insulin, cyclin D1, and BAD, elucidate a new molecular mechanism of insulin in promoting cell proliferation and apoptosis.
Subject(s)
Cell Proliferation , Cyclin D1/genetics , Insulin/genetics , bcl-Associated Death Protein/genetics , Apoptosis/genetics , Cell Line , Cell Line, Tumor , Flow Cytometry , GATA6 Transcription Factor/genetics , GATA6 Transcription Factor/metabolism , Gene Expression Regulation, Neoplastic , Humans , Neoplasms/genetics , Neoplasms/pathology , PPAR alpha/genetics , PPAR alpha/metabolism , Signal Transduction , bcl-Associated Death Protein/metabolismABSTRACT
In recent years, the effect of Toxoplasma gondii infection on psychiatric-related aspects has been increasingly recognized. T. gondii has a high affinity for brain tissue where tachyzoites may form tissue cysts and persist life long. In recent years, 15 serological surveys about T. gondii infection and psychiatric diseases have been carried out in different areas in China. Studies showed that the prevalence of antibodies against T. gondii in psychotic patients was much higher than in normal persons; statistically differences were significant. Studies also reported that raising cats or enjoying the habit of eating raw or under cooked meet were potential risk factors for the infection of T. gondii. The epidemiological and serological evidence support the hypothesis that some psychiatric diseases such as schizophrenia or mental retardation might be linked to T. gondii infection.
Subject(s)
Mental Disorders/epidemiology , Toxoplasmosis/epidemiology , Animals , Cats , China/epidemiology , Geography , Humans , Mental Disorders/etiology , Psychotic Disorders/epidemiology , Psychotic Disorders/etiology , Seroepidemiologic StudiesABSTRACT
BACKGROUND & OBJECTIVE: Malignant fibrous histiocytoma (MFH) is a common soft tissue tumor, which rarely occur in the skeleton. Its histological origin still remains controversial. This study was to investigate the pathologic and X-ray features of primary MFH of bone, and provide reference for imaging diagnosis. METHODS: Clinical data and X-ray images of 16 MFH patients, treated from Jan. 1982 to Jun. 2002 in the First Affiliated Hospital of Soochow University, were analyzed retrospectively. RESULTS: Pathologic manifestations of the patients were malignant multinucleated giant cells, pleomorphic and bizarre form of the tumor cells, and wheel-spoke arrangement of the fibroblast-like cells. Pathologically, the tumor tissue was consisted of various kinds of cells, which were mainly fibroblasts and histiocytes. The principal X-ray manifestations included solitary osteolytic changes, cortical expansion around the tumor, the penetration of the cortex with soft tissue mass formation, slight periosteal reaction and pathologic fracture. CONCLUSION: The diagnosis of MFH mainly depends on pathologic examination and X-ray manifestations.