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Heverin M.,Karolinska Institutet | Ali Z.,Karolinska Institutet | Olin M.,Karolinska Institutet | Tillander V.,Karolinska Institutet | And 7 more authors.
Journal of Steroid Biochemistry and Molecular Biology

27-Hydroxycholesterol (27OH) is a strong suppressor of cholesterol synthesis and a weak activator of LXR in vitro. The regulatory importance of 27OH in vivo is controversial.Here we utilized male mice with increased levels of 27OH either due to increased production (CYP27A1 transgenic mice) or reduced metabolism (Cyp7b1-/- mice). We also used mice lacking 27OH due to a knockout of Cyp27a1. The latter mice were treated with cholic acid to compensate for reduced bile acid synthesis. The effects of the different levels of 27OH on Srebp- and other LXR-regulated genes in the liver were investigated. In the liver of CYP27tg mice we found a modest increase of the mRNA levels corresponding to the LXR target genes Cyp7b1 and Abca1. A number of other LXR-regulated genes were not affected. The effect on Abca1 mRNA was not seen in the liver of Cyp7b1-/- mice. There were little or no effects on cholesterol synthesis. In the liver of the Cyp27-/- mice treated with 0.025% cholic acid there was no significant effect of the knockout on the LXR target genes.In a previous work triple-knockout mice deficient in the biosynthesis of 24. S-hydroxycholesterol, 25-hydroxycholesterol and 27OH were shown to have impaired response to dietary cholesterol, suggesting side-chain oxidized oxysterols to be mediators in cholesterol-induced effects on LXR target genes at a transcriptional level (Chen W. et al., Cell Metab. 5 (2007) 73-79). The hydroxylated oxysterol responsible for the effect was not defined. We show here that treatment of wildtype mice with dietary cholesterol under the same conditions as in the above study induced the LXR target genes Lpl, Abcg8 and Srebp1c in wild type mice but failed to activate the same genes in mice lacking 27-hydroxycholesterol due to a knockout of Cyp27. We failed to demonstrate the above effects at the protein level (Abcg8) or at the activity level (Lpl).The results suggest that 27OH is not an important regulator of Srebp- or LXR regulated genes under basal conditions in mouse liver. On the other hand 27OH appears to mediate cholesterol-induced effects on some LXR target genes at a transcriptional level under some in vivo conditions. © 2016 Elsevier Ltd. Source

Elad S.,University of Rochester | Meidan I.,Hebrew University of Jerusalem | Sellam G.,Hebrew University of Jerusalem | Simaan S.,Hebrew University of Jerusalem | And 4 more authors.
Alternative Therapies in Health and Medicine

Background Oral mucositis is a common complication of cancer therapy. Animal models suggest that curcumin may prevent oral mucositis. To date, no clinical studies have been reported. Objective The primary aim of this pilot study was to assess the tolerability of a curcumin mouthwash. The secondary aim was to describe oral mucositis in pediatric patients undergoing doxorubicin-containing chemotherapy who were using the curcumin mouthwash. Method The research team had originally designed a placebo-controlled study, but gastrointestinal adverse events (nausea and vomiting) affected the compliance of the first three participants who entered the study. An independent researcher found that all three had received the placebo. Believing it unethical to continue using the study's original design, the research team discontinued the control group, and the resulting study is comparable to a case series. Setting The research team performed the study at Hadassah University Medical Center in Jerusalem, Israel. Participants Participants were seven pediatric and young-adult oncology patients. Intervention In addition to standard, preventive oral care (chlorhexidine 0.2% mouthwash for 30 s twice per day), participants also used 10 drops of Curcumall twice per day in a mouthwash during treatment with highdose chemotherapy. Primary Outcome Measures Oral mucositis was assessed on days 0, 7, 10, 14, and 21. The World Health Organization (WHO) scale, the Oral Mucositis Assessment Scale (OMAS), and a Visual Analog pain scale (VAS; patient reporting scale of 0-10) were used. Adverse events were tracked. Results No oral adverse events were documented. No systemic adverse events that possibly could be related to the use of the curcumin mouthwash were observed. In the four patients who fulfilled the compliance criteria, the WHO, OMAS and VAS scores were lower than the severity of oral mucositis previously reported in the literature. Four out of the five participants developed OM, but the values were low, reflecting a relatively mild case. Conclusion In this study, the research team suggested that curcumin mouthwash was safe and well-tolerated. More research is warranted about the efficacy of topical curcumin in the prevention of oral mucositis. Source

Ali Z.,Karolinska Institutet | Heverin M.,Karolinska Institutet | Olin M.,Karolinska Institutet | Acimovic J.,Karolinska Institutet | And 7 more authors.
Journal of Lipid Research

The two oxysterols, 27-hydroxycholesterol (27OH) and 24S-hydroxycholesterol (24OH), are both inhibitors of cholesterol synthesis and activators of the liver X receptor (LXR) in vitro. Their role as physiological regulators under in vivo conditions is controversial, however. In the present work, we utilized a previously described mouse model with overexpressed human sterol 27-hydroxylase (CYP27A1). The levels of 27OH were increased about 12-fold in the brain. The brain levels of HMG-CoA reductase mRNA and HMG-CoA synthase mRNA levels were increased. In accordance with increased cholesterol synthesis, most of the cholesterol precursors were also increased. The level of 24OH, the dominating oxysterol in the brain, was decreased by about 25%, most probably due to increased metabolism by CYP27A1. The LXR target genes were unaffected or slightly changed in a direction opposite to that expected for LXR activation. In the brain of Cyp27 -/- mice, cholesterol synthesis was slightly increased, with increased levels of cholesterol precursors but normal mRNA levels of HMG-CoA reductase and HMG-CoA synthase. The mRNA levels corresponding to LXR target genes were not affected. The results are consistent with the possibility that both 24OH and 27OH are physiological suppressors of cholesterol synthesis in the brain. The results do not support the contention that 27OH is a general activator of LXR target genes in this organ. Copyright © 2013 by the American Society for Biochemistry and Molecular Biology, Inc. Source

Kaufman B.,Sheba Medical Center | Shapira-Frommer R.,Sheba Medical Center | Schmutzler R.K.,Center for Familial Breast and Ovarian Cancer | Audeh M.W.,Samuel Oschin Cancer Institute | And 12 more authors.
Journal of Clinical Oncology

Purpose: Olaparib is an oral poly (ADP-ribose) polymerase inhibitor with activity in germline BRCA1 and BRCA2 (BRCA1/2) -associated breast and ovarian cancers. We evaluated the efficacy and safety of olaparib in a spectrum of BRCA1/2-associated cancers. Patients and Methods: This multicenter phase II study enrolled individuals with a germline BRCA1/2 mutation and recurrent cancer. Eligibility included ovarian cancer resistant to prior platinum; breast cancer with ≥ three chemotherapy regimens for metastatic disease; pancreatic cancer with prior gemcitabine treatment; or prostate cancer with progression on hormonal and one systemic therapy. Olaparib was administered at 400 mg twice per day. The primary efficacy end point was tumor response rate. Results: A total of 298 patients received treatment and were evaluable. The tumor response rate was 26.2% (78 of 298; 95% CI, 21.3 to 31.6) overall and 31.1% (60 of 193; 95% CI, 24.6 to 38.1), 12.9% (eight of 62; 95% CI, 5.7 to 23.9), 21.7% (five of 23; 95% CI, 7.5 to 43.7), and 50.0% (four of eight; 95% CI, 15.7 to 84.3) in ovarian, breast, pancreatic, and prostate cancers, respectively. Stable disease ≥ 8 weeks was observed in 42% of patients (95% CI, 36.0 to 47.4), including 40% (95% CI, 33.4 to 47.7), 47% (95% CI, 34.0 to 59.9), 35% (95% CI, 16.4 to 57.3), and 25% (95% CI, 3.2 to 65.1) of those with ovarian, breast, pancreatic, or prostate cancer, respectively. The most common adverse events (AEs) were fatigue, nausea, and vomiting. Grade ≥ 3 AEs were reported for 54% of patients; anemia was the most common (17%). Conclusion: Responses to olaparib were observed across different tumor types associated with germline BRCA1/2 mutations. Olaparib warrants further investigation in confirmatory studies. © 2014 by American Society of Clinical Oncology. Source

Warner A.,Hadassah Hebrew University Hospital | Ovadia H.,Hadassah Hebrew University Hospital | Ovadia H.,Hebrew University of Jerusalem | Tarcic N.,Hebrew University of Jerusalem | Weidenfeld J.,Hadassah Hebrew University Hospital

Objective: Reciprocal pathways of interaction between the nervous and immune systems during stress may be regulated by stress-induced circulating glucocorticoids that act via type II glucocorticoid receptors (GRs). The aim of the present study was to investigate the effect of restraint stress on GRs in lymphocytes and the role of the sympathetic system in this effect. Methods: We used male Balb/c mice which were adrenalectomized 3 days before exposure to restraint stress (4 h). Specific binding of 3H-dexamethasone (Dex) and the expression of GR protein were measured in the cytosol of spleen cells. Results: Restraint stress caused a significant increase in the maximal binding of 3H-Dex to GRs in the cytosol of spleen cells but not in the binding affinity. In correlation with this increase in binding, restraint stress caused an increase in the amount of GR protein. To establish the relation of the nervous system in this stress response, we blocked the autonomic innervations to the spleen with the ganglionic blocker chlorisondamine. This blocker abrogated the stress-induced increase in the binding of 3H-Dex to GRs and in the GR protein levels. Abrogation of the stress response was also achieved by blocking β-adrenergic receptors. Conclusion: These results suggest that stress-induced increase in the level of GRs is mediated by the sympathetic nervous system via β-adrenergic receptors. It is possible that stress modulation of lymphocyte GR levels may be implicated in the bidirectional communication between the nervous and the immune systems. © 2010 S. Karger AG. Source

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