Effect of Ethanolic Extracts from Taiwanofungus camphoratus and T. salmoneus (Agaricomycetes) Mycelia on Osteoporosis Recovery.

Osteoporosis is common in postmenopausal women and elderly people. In this study, the ovariectomized mice were used as an in vivo test to evaluate the effects of 70% ethanolic extracts of Taiwanofungus camphoratus and T. salmoneus (Polyporales, Agaricomycetes) on postmenopausal osteoporosis. Ovariectomized mice had significantly higher body weight and histopathological alterations of the liver were found to have diffused fatty infiltrated vesicles. The bone parameters of the femur were determined by microcomputed tomography. In addition, the relative weight of the uterus is significantly lower and atrophy of the uterine glands was found in histopathological alterations. The results of trabecular bone parameters showed that feeding high doses of T. camphoratus mycelia ethanolic extract to ovariectomized mice had the ability to delay bone loss. The bone density of trabecular bone and cortical bone were also significantly higher than those of ovariectomized mice, indicating that the ethanolic extract of T. camphoratus has the potential to delay the occurrence of osteoporosis.

Association between Early Acute Respiratory Distress Syndrome after Living-Donor Liver Transplantation and Perioperative Serum Biomarkers: The Role of Club Cell Protein 16.

BACKGROUND: Acute respiratory distress syndrome (ARDS) after living-donor liver transplantation (LDLT) is not uncommon, but it lacks the biomarkers for early detection. Club cell protein 16 (CC16), high-motility group box 1 protein (HMGB1), interleukin-1ß (IL-1ß), and IL-10 have been reported as relevant to the development of ARDS. However, they have not been investigated during LDLT. METHODS: Seventy-three consecutive recipients undergoing LDLT were enrolled and received the same perioperative care plan. Perioperative serum CC16, HMGB1, IL-1ß, and IL-10 levels were measured at the pretransplant state, 30 minutes after reperfusion, postoperative day 1 (POD1), and POD3. ARDS was diagnosed according to the 2012 Berlin definition. RESULTS: Of the 73 recipients, 13 developed ARDS with significantly longer durations of mechanical ventilation and intensive care unit stay. Serum CC16 levels on POD1 increased significantly from the pretransplant state in the ARDS group but not in the non-ARDS group. Pretransplant serum CC16 levels were also higher in the ARDS group. The area under the receiver operating characteristic curves for POD1 serum CC16 levels used to discriminate ARDS was 0.803 (95% confidence interval: 0.679 to 0.895; p < 0.001). By comparison, HMGB1, IL-1ß, and IL-10 were not associated with ARDS after LDLT. CONCLUSION: The higher pretransplant serum CC16 level and its increased level on POD1 were associated with the development of early ARDS after LDLT. This trial is registered with NCT01936545, 27 August 2013.

Genomic and proteomic analysis of transcription factor TFII-I reveals insight into the response to cellular stress.

The ubiquitously expressed transcription factor TFII-I exerts both positive and negative effects on transcription. Using biotinylation tagging technology and high-throughput sequencing, we determined sites of chromatin interactions for TFII-I in the human erythroleukemia cell line K562. This analysis revealed that TFII-I binds upstream of the transcription start site of expressed genes, both upstream and downstream of the transcription start site of repressed genes, and downstream of RNA polymerase II peaks at the ATF3 and other stress responsive genes. At the ATF3 gene, TFII-I binds immediately downstream of a Pol II peak located 5 kb upstream of exon 1. Induction of ATF3 expression increases transcription throughout the ATF3 gene locus which requires TFII-I and correlates with increased association of Pol II and Elongin A. Pull-down assays demonstrated that TFII-I interacts with Elongin A. Partial depletion of TFII-I expression caused a reduction in the association of Elongin A with and transcription of the DNMT1 and EFR3A genes without a decrease in Pol II recruitment. The data reveal different interaction patterns of TFII-I at active, repressed, or inducible genes, identify novel TFII-I interacting proteins, implicate TFII-I in the regulation of transcription elongation and provide insight into the role of TFII-I during the response to cellular stress.

Cell-cycle specific association of transcription factors and RNA polymerase ii with the human ß-globin gene locus.

The human ß-globin genes are regulated by a locus control region (LCR) and are expressed at extremely high levels in erythroid cells. How transcriptional fidelity of highly expressed genes is regulated and maintained during the cell cycle is not completely understood. Here, we analyzed the association of transcription factor USF, the co-activator CBP, topoisomerase I (Topo I), basal transcription factor TFIIB, and RNA polymerase II (Pol II) with the ß-globin gene locus at specific cell-cycle stages. The data demonstrate that while association of Pol II with globin locus associated chromatin decreased in mitotically arrested cells, it remained bound at lower levels at the γ-globin gene promoter. During early S-phase, association of CBP, USF, and Pol II with the globin gene locus decreased. The re-association of CBP and USF2 with the LCR preceded re-association of Pol II, suggesting that these proteins together mediate recruitment of Pol II to the ß-globin gene locus during S-phase. Finally, we analyzed the association of Topo I with the globin gene locus during late S-phase. In general, Topo I association correlated with the binding of Pol II. Inhibition of Topo I activity reduced Pol II binding at the LCR and intergenic regions but not at the γ-globin gene promoter. The data demonstrate dynamic associations of transcription factors with the globin gene locus during the cell cycle and support previous results showing that specific components of transcription complexes remain associated with highly transcribed genes during mitosis.

Role of helix-loop-helix proteins during differentiation of erythroid cells.

Helix-loop-helix (HLH) proteins play a profound role in the process of development and cellular differentiation. Among the HLH proteins expressed in differentiating erythroid cells are the ubiquitous proteins Myc, USF1, USF2, and TFII-I, as well as the hematopoiesis-specific transcription factor Tal1/SCL. All of these HLH proteins exhibit distinct functions during the differentiation of erythroid cells. For example, Myc stimulates the proliferation of erythroid progenitor cells, while the USF proteins and Tal1 regulate genes that specify the differentiated phenotype. This minireview summarizes the known activities of Myc, USF, TFII-I, and Tal11/SCL and discusses how they may function sequentially, cooperatively, or antagonistically in regulating expression programs during the differentiation of erythroid cells.

Defective erythropoiesis in transgenic mice expressing dominant-negative upstream stimulatory factor.

Transcription factor USF is a ubiquitously expressed member of the helix-loop-helix family of proteins. It binds with high affinity to E-box elements and, through interaction with coactivators, aids in the formation of transcription complexes. Previous work demonstrated that USF regulates genes during erythroid differentiation, including HoxB4 and beta-globin. Here, we show that the erythroid cell-specific expression of a dominant-negative mutant of USF, A-USF, in transgenic mice reduces the expression of all beta-type globin genes and leads to the diminished association of RNA polymerase II with locus control region element HS2 and with the beta-globin gene promoter. We further show that the expression of A-USF reduces the expression of several key erythroid cell-specific transcription factors, including EKLF and Tal-1. We provide evidence demonstrating that USF interacts with known regulatory DNA elements in the EKLF and Tal-1 gene loci in erythroid cells. Furthermore, A-USF-expressing transgenic mice exhibit a defect in the formation of CD71(+) progenitor and Ter-119(+) mature erythroid cells. In summary, the data demonstrate that USF regulates globin gene expression indirectly by enhancing the expression of erythroid transcription factors and directly by mediating the recruitment of transcription complexes to the globin gene locus.

Calpeptin increases the activity of upstream stimulatory factor and induces high level globin gene expression in erythroid cells.

Differentiation of erythroid cells is regulated by cell signaling pathways including those that change the intracellular concentration of calcium. Calcium-dependent proteases have been shown previously to process and regulate the activity of specific transcription factors. We show here that the protein levels of upstream stimulatory factor (USF) increase during differentiation of murine erythroleukemia (MEL) cells. USF was subject to degradation by the Ca(2+)-dependent protease m-calpain in undifferentiated but not in differentiated MEL cells. Treatment of MEL cells with the specific calpain inhibitor calpeptin increased the levels of USF and strongly induced expression of the adult alpha- and beta-globin genes. The induction of globin gene expression was associated with an increase in the association of USF and RNA po ly mer ase II with regulatory elements of the beta-globin gene locus. Calpeptin also induced high level alpha- and beta-globin gene expression in primary CD71-positive erythroid progenitor cells. The combined data suggest that inhibition of calpain activity is required for erythroid differentiation-associated increase in globin gene expression.