Parallel study

Abstract: His-dTrp-Ala-Trp-dPhe-Lys-NH2 (GH-RP-6) is a synthetic hexapeptide that specifically releases GH both in vivo and in vitro in pituitary incubates. In this study, for the first time, GH-RP-6 was studied in primary pituitary cell monolayer culture. Parallel studies were performed with human pancreatic GH-releasing factor-44 (hpGRF-44). Culture conditions optimal for GH-RP-6 were not optimal for hpGRF-44. Both peptides released GH in a dose- and time-dependent manner. In this assay system, the ED50 for GH-RP-6 was 9 nm, and the ED50) for hp-GRF-44 was 1.6 nm. Calcium-blocking agents inhibited the GH responses of both peptides as well as basal GH release. Pretreatment with GH-RP-6 decreased the subsequent response to both GH-RP-6 and hpGRF-44. hpGRF-44 downregulated itself but not GH-RP-6. Rat sera potentiated the GH response of hpGRF-44 but not that of GH-RP-6. GH-RP-6 and hpGRF-44 GH responses were additive. These results suggest that GH-RP-6 and hpGRF-44 stimulate GH release via different somatotroph recep...

Abstract: Summary: PRO70769 is a humanized IgG1 monoclonal antibody against the CD20 molecule that is present on normal and malignant B cells. PRO70769 is being evaluated for treatment of B-cell-mediated diseases and is in a phase 1 trial for rheumatoid arthritis. As part of the preclinical toxicology evaluation, B-cell depletion profiles and safety of PRO70769 were assessed in cynomolgus monkeys. Animals were administered drug (IV) on days 1 and 15 with 10, 50, or 100 mg/kg PRO70769 and killed 2 weeks after the second dose and after a 3-month recovery period. In a parallel study, animals were not necropsied but instead were retreated with a second cycle of PRO70769 administered under an identical regimen. PRO70769 suppressed B cells in the blood to undetectable levels and significantly reduced B cells in lymphoid tissues. Splenic B cells were depleted to a greater extent compared with lymph node B cells. A second cycle of treatment resulted in a greater extent of depletion in lymphoid tissues compared with the depletion observed after one cycle of treatment; however, residual B cells in lymphoid tissues were still detectable, even at the highest dose. The rate of B-cell recovery in peripheral blood appeared similar between one and two cycles of treatment. Upon depletion there was a change in the profile of lymph node B-cell subsets. After recovery, B-cell subsets were reconstituted to normal levels. Depletion of CD20-expressing cells and lymphoid follicular atrophy were the only treatment-related effects.

Abstract: We have recently found that suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, improves survival in a lethal model of hemorrhagic shock in rats. The purpose of the present study was to determine whether SAHA treatment would prevent LPS-induced septic shock and improve the survival in a murine model. C57BL/6J mice were randomly divided into two groups. Experimental mice were given intraperitoneal SAHA (50 mg/kg) in vehicle dimethyl sulfoxide fluid (n = 10). The control mice (n = 10) received vehicle dimethyl sulfoxide only. They were injected with LPS (20 mg/kg, i.p.) 2 h later, and the animals from the treatment group were given a second dose of SAHA. Survival was monitored during the next 7 days. In a parallel study, mice treated with or without SAHA were subjected to LPS insult while normal (sham) mice serviced as controls. 1) Lungs were harvested at 3 and 48 h for analysis of gene expression and pathologic changes, respectively; 2) spleens were isolated for analysis of neutrophilic cell population. In addition, RAW264.7 mouse macrophages were cultured to assess the effects of SAHA on LPS-induced inflammation in vitro. All mice in the control group that were subjected to LPS challenge died in less than 48 h. However, SAHA-treated animals displayed a significantly higher 1-week survival rate (87.5%) compared with the control group (0%). Moreover, LPS insult decreased the acetylation of histone proteins (H2A, H2B, and H3), elevated the levels of TNF-alpha in vivo (circulation) and in vitro (culture medium), increased the neutrophilic cell population in the spleen, enhanced the expression of TNF-alpha and IL-1beta genes in lung tissue, and augmented the pulmonary neutrophil infiltration. In contrast, SAHA treatment markedly attenuated all of these LPS-induced alterations. We report for the first time that administration of SAHA (50 mg/kg) significantly attenuates a variety of inflammatory markers and improves long-term survival after a lethal LPS insult.

Abstract: Consumption of isoflavone-rich soyabean protein is reported to reduce total and LDL-cholesterol, but the specific components responsible are undetermined. In a previous crossover trial we showed that purified isoflavones, derived from red clover (Trifolium pratense), raised HDL3-cholesterol in premenopausal women; however, these findings were inconclusive due to period and carryover effects. In an attempt to overcome this problem, we utilised a parallel study designed to re-examine the effects of purified isoflavones on plasma lipoproteins and markers of insulin resistance in premenopausal women. Twenty-five healthy premenopausal women participated in a double-blind, randomised, parallel study. The treatment group (n 12) consumed a placebo for the first menstrual cycle and an isoflavone supplement (86 mg/d, derived from red clover) for three cycles, while the placebo group (n 13) consumed a placebo supplement for four menstrual cycles. Blood samples were collected weekly during cycles 1, 3 and 4. Supplementation with isoflavones resulted in a 15-fold increase in urinary isoflavone excretion (P<0.0001). There were no significant effects on total cholesterol, LDL- and HDL-cholesterol, HDL subfractions, triacylglycerol, lipoprotein(a), glucose or insulin concentrations. Our present results indicate that purified isoflavones derived from red clover have no effect on cholesterol homeostasis or insulin resistance in premenopausal women, a group which is at low risk of CHD.