Metformin Reduces Bleomycin-induced Pulmonary Fibrosis in Mice.

Metformin has anti-inflammatory and anti-fibrotic effects. We investigated whether metformin has an inhibitory effect on bleomycin (BLM)-induced pulmonary fibrosis in a murine model. A total of 62 mice were divided into 5 groups: control, metformin (100 mg/kg), BLM, and BLM with metformin (50 mg/kg or 100 mg/kg). Metformin was administered to the mice orally once a day from day 1. We sacrificed half of the mice on day 10 and collected the bronchoalveolar lavage fluid (BALF) from their left lungs. The remaining mice were sacrificed and analyzed on day 21. The right lungs were harvested for histological analyses. The messenger RNA (mRNA) levels of epithelial-mesenchymal transition markers were determined via analysis of the harvested lungs on day 21. The mice treated with BLM and metformin (50 mg/kg or 100 mg/kg) showed significantly lower levels of inflammatory cells in the BALF compared with the BLM-only mice on days 10 and 21. The histological examination revealed that the metformin treatment led to a greater reduction in inflammation than the treatment with BLM alone. The mRNA levels of collagen, collagen-1, procollagen, fibronectin, and transforming growth factor-ß in the metformin-treated mice were lower than those in the BLM-only mice on day 21, although statistical significance was observed only in the case of procollagen due to the small number of live mice in the BLM-only group. Additionally, treatment with metformin reduced fibrosis to a greater extent than treatment with BLM alone. Metformin suppresses the inflammatory and fibrotic processes of BLM-induced pulmonary fibrosis in a murine model.

The immune modulation of Clara cell-10 in human peripheral monocytes and dendritic cells.

Although Clara cell secretory protein (CC-10, CC-16 or uteroglobin, secretoglobin 1A1) has been ascribed anti-inflammatory, immunomodulatory and anti-cancer activity roles in lung diseases including lung cancer, its precise function remains unclear. The objective of the present study was to evaluate the role of CC-10 in the immunomodulation of human monocytes and dendritic cells (DCs). The human lung adenocarcinoma cell line A549, was used to examine PGE2 production after cyclooxygenase (COX) inhibition and adenovirus encoding human CC-10 cDNA (Ad-CC-10) transfection. Type I and II cytokines were measured from peripheral blood mononuclear cells (PBMCs) and DCs which were cultured with tumor supernatant (TSN) or Ad-CC-10 transfected TSN. When PBMCs were cultured with supernatant A549 (tumor supernatant, TSN), the levels of T-cell helper type 1 (Th1) and 2 (Th2) cytokines increased. However, CC-10 inhibited the induction of Th2 cytokines of PBMCs stimulated with TSN. In DCs, TSN inhibited Th1 type cytokines but induced Th2 type. In contrast, TSN treated with either CC-10 or NS398 (COX-2 inhibitor) stimulated Th1 type and inhibited Th2 type without any phenotypic changes. The supernatants generated in the presence of NS-398 or CC-10 prevented tumor-induced inhibition of allogeneic T-cell stimulation. While the level of interleukin (IL)-10 secretion from DC-Ad-CC-10 was decreased, the level of IL-12 secretion was increased by CC-10. Collectively our data suggest that a supernatant of NSCLC causes an imbalance in the immune response of PBMCs and DCs, which is reversed by CC-10. This suggests that CC-10 is a candidate for the development of a new immunotherapy for lung cancer.

Identification of genes related to Parkinson's disease using expressed sequence tags.

In a search for novel target genes related to Parkinson's disease (PD), two full-length cDNA libraries were constructed from a human normal substantia nigra (SN) and a PD patient's SN. An analysis of the gene expression profiles between them was done using the expressed sequence tags (ESTs) frequency. Data for the differently expressed genes were verified by quantitative real-time RT-PCR, immunohistochemical analysis and a cell death assay. Among the 76 genes identified with a significant difference (P > 0.9), 21 upregulated genes and 13 downregulated genes were confirmed to be differentially expressed in human PD tissues and/or in an MPTP-treated mice model by quantitative real-time RT-PCR. Among those genes, an immunohistochemical analysis using an MPTP mice model for alpha-tubulin including TUBA3 and TUBA6 showed that the protein levels are downregulated, as well as the RNA levels. In addition, MBP, PBP and GNAS were confirmed to accelerate cell death activity, whereas SPP1 and TUBA3 to retard this process. Using an analysis of ESTs frequency, it was possible to identify a large number of genes related to human PD. These new genes, MBP, PBP, GNAS, SPP1 and TUBA3 in particular, represent potential biomarkers for PD and could serve as useful targets for elucidating the molecular mechanisms associated with PD.

The merlin tumor suppressor interacts with Ral guanine nucleotide dissociation stimulator and inhibits its activity.

Neurofibromatosis type 2 (NF2) is the most commonly mutated gene in benign tumors of the human nervous system such as schwannomas and meningiomas. The NF2 gene encodes a protein called schwannomin or merlin, which is involved in regulating cell growth and proliferation through protein-protein interactions with various cellular proteins. In order to better understand the mechanism by which merlin exerts its function, yeast two-hybrid screening was performed and Ral guanine nucleotide dissociation stimulator (RalGDS), a downstream molecule of Ras, was identified as a merlin-binding protein. The direct interaction between merlin and RalGDS was confirmed both in vitro and in the NIH3T3 cells. The domain analyses revealed that the broad C-terminal region of merlin (aa 141-595) is necessary for the interaction with the C-terminal Ras-binding domain (RBD) of RalGDS. Functional studies showed that merlin inhibits the RalGDS-induced RalA activation, the colony formation and the cell migration in mammalian cells. These results suggest that merlin can function as a tumor suppressor by inhibiting the RalGDS-mediated oncogenic signals.