Immediate early genes and p21 regulation in liver of rats with acute hepatic failure

It has been observed that liver regeneration in acute hepatic failure (AHF) is suppressed [Eguchi et al. Hepatology 1996;24(6):1452-9]. The molecular mechanism regulating this inhibition is not known. We previously reported that in AHF rats, hepatocyte proliferation was significantly impaired with elevation in serum IL-6, TGF-beta1, and HGF [Kamohara et al. Biochem Biophys Res Commun 2000;273(1):129-35]. Following either 70% partial hepatectomy (PH) or liver injury, quiescent mature hepatocytes are "primed" to re-enter the cell cycle. The process of "priming" appears to be triggered by extracellular cytokines (IL-6 and TNF-alpha) and is characterized by expression of immediate early genes. Under the stimulation of growth factors such as HGF, "primed" hepatocytes exit the G1 phase of the cell cycle. G1-associated cyclins and their inhibitors play a pivotal role in G1/S cell cycle transition. Here, we demonstrate that immediate early gene (i.e. c-myc, c-fos) expression and AP-1 activity are preserved in AHF rat livers despite absence of hepatocyte proliferation. In contrast, p21 mRNA and protein are both over-expressed in AHF livers compared to livers from rats undergoing PH; this elevation leads to inhibition in Cdk2 activity, resulting in G1 cell cycle arrest and inhibition of regeneration.     

A novel molecular marker of pituitary tumor transforming gene involves in a rat liver regeneration

BACKGROUND: Pituitary tumor transforming gene (PTTG), homologous to a mammalian securin, plays a pivotal role in cell transformation, however, its biological function(s) in normal tissues is not fully understood. Because the liver is a regenerative organ, the relevant biological function of PTTG in the liver would be more feasible to understand PTTG. Also, PTTG may be involved in the liver regeneration. MATERIALS AND METHODS: Expressions of rat hepatic PTTG messengerRNA (mRNA) and cellular immunoreactivities during the cell proliferative period of the liver regeneration both in vitro and in vivo were tested. RESULTS: PTTG expression of the rat primary hepatocyte was stimulated by HGF in a dose dependent manner, and was suppressed when hepatocyte proliferation was inhibited by transforming growth factor-beta1. A positive PTTG immunoreactive co-localizing with 5-bromo-2'-deoxyuridine (BrdU) in the hepatocyte nucleus was found and there was a concurrent sister chromatin itself by the immunofluorescent labeling of PTTG with cytokeratin 18 (CK18). DISCUSSION: Since the correlation of PTTG mRNA expression, cell proliferation and immunoreactivity were observed in primary rat cultured hepatocytes, PTTG may be a novel marker of cell proliferation both in vitro and in vivo liver regeneration.     

The effect of antioxidants and a caspase inhibitor on cryopreserved rat hepatocytes

Hepatocyte transplantation and use of bioartificial liver support systems have been suggested as potential therapies for fulminant hepatic failure. Cryopreservation in liquid nitrogen is presently the major method of long-term storage of isolated hepatocytes. However, cryopreservation can result in low cell recovery and reduction in differentiated function. Several possible mechanisms of cell death during cryopreservation have been proposed. The most important mechanisms appear to be oxidative stress and apoptosis. In this study, we isolated fresh rat hepatocytes and cryopreserved them in three media: University of Wisconsin (UW) solution, an antioxidant-containing medium, and medium containing a caspase inhibitor. Viability and function of hepatocytes cryopreserved in these media were examined. Cryopreservation conditions had no effect on hepatocyte viability after thawing. However, after culture we found significant improvements in viability and function in both antioxidant- and caspase inhibitor-treated hepatocytes at 6 and 24 h.     

Endometrial plasma cells: do they indicate subclinical pelvic inflammatory disease?

BACKGROUND: Subclinical pelvic inflammatory disease (PID) is a common condition among women with lower genital tract infection and is believed to be responsible for a greater proportion of PID-related sequelae than acute PID. Subclinical PID is diagnosed histologically after endometrial biopsy. In the literature, many different histologic criteria have been used to define subclinical PID. GOAL: To determine if endometrial plasma cells are commonly found in women at low likelihood of PID. STUDY: A cross-sectional study of 33 women undergoing tubal ligation and at low likelihood of PID was performed. At the time of tubal ligation, study participants underwent visualization of pelvic organs and an endometrial biopsy, which was analyzed for the presence of neutrophils and plasma cells. Demographic, clinical, and microbiologic data were compared among women with and without endometrial plasma cells. RESULTS: Endometrial plasma cells were identified in one third (33%) of the asymptomatic, fertile, healthy women in our cohort. The presence of plasma cells was not associated with lower genital tract infection, including bacterial vaginosis. Laparoscopic evidence of fallopian tube damage was similar in patients with and without endometrial plasma cells (22% in each group). CONCLUSION: Plasma cells are commonly found in the endometria of healthy women and may not represent upper genital tract inflammation.     

Bilateral renal artery stenting in a patient with Leriche syndrome

Stenting for renal artery stenosis is well described in the literature. Bilateral renal artery stenting is not such a common procedure, however it is quite rare in patients with Leriche syndrome, as is the case we present.     

Generation of multiple angiogenesis inhibitors by human pancreatic cancer

A primary inoculum of human pancreatic cancer cells (BxPC-3) has the ability to inhibit the growth of a secondary tumor in an in vivo animal model. Such ability suggests that the primary tumor is producing inhibitors that act at the site of the secondary tumor. Accordingly we attempted to discover which inhibitors are produced by pancreatic cancer cells. We determined that pancreatic cancer cells process angiostatin isoforms from plasminogen. Additionally, we isolated and characterized an uncleaved "latent" antiangiogenic antithrombin (aaAT) molecule processed from systemically available AT by pancreatic cancer cells as well as a cleaved form of aaAT processed from systemically available AT by pancreatic cancer cells. Human AT, cleaved with human neutrophil elastase, inhibits angiogenesis in the chorioallantoic membrane assay. This human aaAT molecule is able to inhibit the growth of pancreatic tumors in immune-compromised mice. Our work represents the first demonstration of multiple angiogenesis inhibitors from a single tumor and suggests that antiangiogenic therapies may provide an avenue for future treatment of pancreatic cancer.     

Radiation and Concomitant Weekly Administration of Paclitaxel in Patients with Glioblastoma Multiforme. A Phase II Study

The present study was conducted to evaluate the activity and toxicity profile of radiation (RT) and concomitant chemotherapy in patients with glioblastoma multiforme (GBM). Thirty-nine patients were treated postoperatively with RT and concomitant administration of paclitaxel. Cranial irradiation was initiated 2–3 weeks postoperatively and was administered in 2.0 fractions, one fraction per day, for 5 consecutive days per week, to a total of 60Gy. Paclitaxel was delivered at a dose of 100mg/m² over 3-h once weekly for 6 weeks.Thirty-three patients received all 6 cycles of paclitaxel according to the protocol. Totally, 217 cycles were delivered all of them at full dose. The median relative dose intensity of paclitaxel was 1 (range 0.88–1.1). Three (7.5%) patients achieved complete and 9 (23%) partial response, while 12 (30.5%) patients demonstrated stabilization of the disease. Side effects from combined chemoradiotherapy were mainly mild. Grade III toxicity included infection (7.5%) and alopecia (5%). Median time to progression was 6 (range 0.9–27) months and median survival 10.7 (range 0.9–39.5+) months.The present study has clearly shown that 100mg/m² of paclitaxel in 1-h infusion weekly can be safely given concomitantly with RT in patients with GBM with manageable toxicity. However, the efficacy of this combined modality treatment does not appear to be superior to that of RT alone.     

The proteasome inhibitor bortezomib drastically affects inflammation and bone disease in adjuvant‐induced arthritis in rats

Objective

To explore the effect of bortezomib in splenocytes and fibroblast‐like synoviocytes (FLS) and its in vivo potency in a rat model of adjuvant‐induced arthritis (AIA), which resembles human rheumatoid arthritis (RA).

Methods

AIA was induced with Freund's complete adjuvant. Splenocyte and FLS proliferation and apoptosis were measured by radioactivity incorporation and flow cytometry, respectively. The invasiveness of FLS from rats with AIA was tested in a Transwell system. The pattern of cytokine secretion was evaluated by cytometric bead array in splenocyte supernatants. Bortezomib was administered prophylactically or therapeutically, and arthritis was assessed clinically and histologically. Immunohistochemistry was performed for markers of inflammation and angiogenesis in joints. Hematologic and biochemical parameters were tested in peripheral blood (PB). Representative animals were examined by computed tomography (CT) scanning before and after bortezomib administration. The expression of Toll‐like receptor 2 (TLR‐2), TLR‐3, and TLR‐4 in PB and FLS was measured by real‐time polymerase chain reaction, and alterations in specific cell populations in PB and spleen were determined by flow cytometry.

Results

In vitro, bortezomib exhibited significant inhibitory and proapoptotic activity in splenocytes and FLS from rats with AIA, altered the inflammatory cytokine pattern, and reduced the invasiveness of FLS from rats with AIA. In vivo, bortezomib significantly ameliorated disease severity. Remission was associated with improved histology and decreased expression of CD3, CD79a, CD11b, cyclooxygenase 1, and factor VIII in target tissues as well as down‐regulation of TLR expression in PB and cultured FLS. CT scanning demonstrated a bone healing effect after treatment.

Conclusion

Our findings suggest that bortezomib affects AIA in a pleiotropic manner and that this drug may be effective in RA.