The perspective of celiac disease patients on emerging treatment options and non-celiac gluten sensitivity.

BACKGROUND: Non-celiac gluten sensitivity (NCGS) and emerging treatment options are hot topics in the celiac disease (CeD) scientific literature. However, very little is known about the perspective on these issues of CeD patients. METHODS: We performed a large patient survey among unselected CeD patients in Switzerland. RESULTS: A total of 1689 patients were analyzed. 57.5% have previously heard of NCGS. 64.5% believe in the existence of this entity. Regarding a potential influence of NCGS on CeD awareness, 31.7% show a positive and 27.5% a negative perception. Patients with prior use of alternative medicine and women more often have heard of and believe in the existence of NCGS vs. those never having used alternative methods and men, respectively (66.9 vs. 56.9%, p=0.001 and 78.5 vs. 69.0%, p=0.001; 60.7 vs. 44.2%, p<0.001 and 71.0 vs. 60.8%, p=0.002). Women and patients ≥30 years more often show a negative attitude towards NCGS (32.2% vs. 24.8%, p=0.024 and 32.2% vs. 24.2%, p=0.018). With regard to emerging treatment options for CeD, 43.3% have previously heard of novel agents, more women than men (46.0 vs. 38.0%, p=0.019). CONCLUSIONS: Perception of and attitude towards NCGS differ depending on sex, age and prior use of alternative medicine. Knowledge of the progress towards emerging treatment options is currently limited.

Patients' perceptions on the impact of coffee consumption in inflammatory bowel disease: friend or foe?--a patient survey.

BACKGROUND: Environmental factors are an integral component in the pathogenesis of inflammatory bowel disease (IBD). There is an increasing interest in nutritive components. While the potential disease-modifying role of coffee has been intensively investigated in a variety of gastrointestinal diseases, the data on the potential impact on IBD is very limited. We aimed to determine the patients' perspective on coffee consumption in IBD. METHODS: We conducted a questionnaire among IBD patients in Switzerland, assessing key questions regarding coffee consumption. Descriptive statistics including chi square testing were used for analysis of questionnaire data. RESULTS: Among a total of 442 patients 73% regularly consume coffee. 96% of patients attributing a positive and 91% of patients attributing no impact of coffee intake on IBD regularly drink coffee and surprisingly even 49% of those patients that assign a negative impact on disease symptoms. Among those patients refraining from regular coffee intake 62% are convinced that coffee adversely influences intestinal symptoms, significantly more in Crohn's disease (CD) than in ulcerative colitis (UC) (76% vs. 44%, p = 0.002). In total, 38% of all study subjects suppose that coffee has an effect on their symptoms of disease, significantly more in CD (54%) compared to UC patients (22%, p < 0.001). Moreover, while 45% of CD patients feel that coffee has a detrimental influence, only 20% of UC patients share this impression (p < 0.001). CONCLUSION: Two thirds of IBD patients regularly consume coffee. More than twice as many CD compared to UC patients attribute a symptom-modifying effect of coffee consumption, the majority a detrimental one. However, this negative perception does not result in abstinence from coffee consumption.

Sphingomyelin and phosphatidylcholine contrarily affect the induction of apoptosis in intestinal epithelial cells.

SCOPE: The major alimentary sources for the plasma membrane lipid sphingomyelin (SM) are dairy products, eggs, and meat. We recently reported that the SM metabolite ceramide induces cathepsin D mediated apoptosis in murine intestinal epithelial cells (IECs) and increases inflammation in acute colitis. We investigated the impact of SM and phosphatidylcholine on apoptosis in human IECs and point out BH3-interacting death agonist (BID) as link between cathepsin D and apoptosis. METHODS AND RESULTS: HT-29 and isolated human IECs were stimulated with SM or phosphatidylcholine. SM treatment resulted in increased apoptosis. Phosphatidylcholine showed contrary effects. Western revealed higher amounts of cathepsin D and BID activation upon lipid stimulation. Western blotting revealed BID activation through SM in both an induced and a spontaneous mouse model of colitis. CONCLUSION: Dietary phospholipids may induce or abolish apoptosis in IECs and seem to play a role in the pathogenesis of inflammatory bowel diseases. This nutritional factor might be considered when evaluating the pathogenesis of inflammatory bowel diseases. Effects of SMase- and SM treatment on inflammation in dextran sulfate sodium induced animal models of colitis and in vitro experiments are discussed as controversial. Variable sources of SM, feeding techniques, and mouse strains might play a role.

Activation of protein tyrosine phosphatase non-receptor type 2 by spermidine exerts anti-inflammatory effects in human THP-1 monocytes and in a mouse model of acute colitis.

BACKGROUND: Spermidine is a dietary polyamine that is able to activate protein tyrosine phosphatase non-receptor type 2 (PTPN2). As PTPN2 is known to be a negative regulator of interferon-gamma (IFN-γ)-induced responses, and IFN-γ stimulation of immune cells is a critical process in the immunopathology of inflammatory bowel disease (IBD), we wished to explore the potential of spermidine for reducing pro-inflammatory effects in vitro and in vivo. METHODS: Human THP-1 monocytes were treated with IFN-γ and/or spermidine. Protein expression and phosphorylation were analyzed by Western blot, cytokine expression by quantitative-PCR, and cytokine secretion by ELISA. Colitis was induced in mice by dextran sodium sulfate (DSS) administration. Disease severity was assessed by recording body weight, colonoscopy and histology. RESULTS: Spermidine increased expression and activity of PTPN2 in THP-1 monocytes and reduced IFN-γ-induced phosphorylation of signal transducer and activator of transcription (STAT) 1 and 3, as well as p38 mitogen-activated protein kinase (MAPK) in a PTPN2 dependent manner. Subsequently, IFN-γ-induced expression/secretion of intracellular cell adhesion molecule (ICAM)-1 mRNA, monocyte chemoattractant protein (MCP)-1, and interleukin (IL)-6 was reduced in spermidine-treated cells. The latter effects were absent in PTPN2-knockdown cells. In mice with DSS-induced colitis, spermidine treatment resulted in ameliorated weight loss and decreased mucosal damage indicating reduced disease severity. CONCLUSIONS: Activation of PTPN2 by spermidine ameliorates IFN-γ-induced inflammatory responses in THP-1 cells. Furthermore, spermidine treatment significantly reduces disease severity in mice with DSS-induced colitis; hence, spermidine supplementation and subsequent PTPN2 activation may be helpful in the treatment of chronic intestinal inflammation such as IBD.

Preoperative chemosensitivity testing as Predictor of Treatment benefit in Adjuvant stage III colon cancer (PePiTA): protocol of a prospective BGDO (Belgian Group for Digestive Oncology) multicentric study.

BACKGROUND: Surgery is a curative treatment for patients with locally advanced colon cancer, but recurrences are frequent for those with stage III disease. FOLFOX adjuvant chemotherapy has been shown to improve recurrence-free survival and overall survival by more than 20% and is nowadays considered a standard of care. However, the vast majority of patients will not benefit from receiving cytotoxic drugs because they have either already been cured by surgery or because their tumor cells are resistant to the chemotherapy, for which predictive factors are still not available. METHODS/DESIGN: PePiTA is a prospective, multicenter, non-randomised trial built on the hypothesis that preoperative chemosensitivity testing using FDG-PET/CT before and after one course of FOLFOX can identify the patients who are unlikely to benefit from 6 months of adjuvant FOLFOX treatment for stage III colon cancer. DISCUSSION: PePiTA is the first study to use the primitive tumor chemosensitivity assessed by metabolic imaging as a guidance for adjuvant therapy in colon cancer. It could pave the way for tailoring the treatment and avoiding useless toxicities for the patients and inadequate expenses for the society. It could also give an interesting insight into tumoral heterogeneity, resistance to chemotherapy, genetic predisposants to oxaliplatin toxicity and immune response to cancer. EUDRACT NUMBER: 2009-011445-13 TRIAL REGISTRATION: ClinicalTrials.gov number, NCT00994864.

Bilberry ingestion improves disease activity in mild to moderate ulcerative colitis - an open pilot study.

BACKGROUND AND AIMS: A significant fraction of patients with ulcerative colitis (UC) is not sufficiently controlled with conventional therapy or suffers from therapy related side effects. Anthocyanins, highly abundant in bilberries (Vaccinium myrtillus), were shown to have antioxidative and anti-inflammatory effects. We aimed to explore the therapeutic potential of bilberries in active UC. METHODS: In an open pilot trial with a total follow-up of 9 weeks the effect of a daily standardized anthocyanin-rich bilberry preparation was tested in 13 patients with mild to moderate UC. Clinical, biochemical, endoscopic and histologic parameters were assessed. RESULTS: At the end of the 6 week treatment interval 63.4% of patients achieved remission, the primary endpoint, while 90.9% of patients showed a response. In all patients a decrease in total Mayo score was detected (mean: 6.5 and 3.6 at screening and week 7, respectively; p<0.001). Fecal calprotectin levels significantly decreased during the treatment phase (baseline: mean 778 µg/g, range 192-1790 µg/g; end of treatment: mean 305 µg/g, range <30-1586 µg/g; p=0.049), including 4 patients achieving undetectable levels at end of treatment. A decrease in endoscopic Mayo score and histologic Riley index confirmed the beneficial effect. However, an increase of calprotectin levels and disease activity was observed after cessation of bilberry intake. No serious adverse events were observed. CONCLUSIONS: This is the first report on the promising therapeutic potential of a standardized anthocyanin-rich bilberry preparation in UC in humans. These results clearly indicate a therapeutic potential of bilberries in UC. Further studies on mechanisms and randomized clinical trials are warranted.

Effect of silymarin (milk thistle) on liver disease in patients with chronic hepatitis C unsuccessfully treated with interferon therapy: a randomized controlled trial.

CONTEXT: The botanical product silymarin, an extract of milk thistle, is commonly used by patients to treat chronic liver disease, despite scant and conflicting evidence of its efficacy. OBJECTIVE: To determine the effect of silymarin on liver disease activity in patients with chronic hepatitis C virus (HCV) infection unsuccessfully treated with interferon-based therapy. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, double-blind, placebo-controlled trial conducted at 4 medical centers in the United States. Participants included 154 persons with chronic HCV infection and serum alanine aminotransferase (ALT) levels of 65 U/L or greater who were previously unsuccessfully treated with interferon-based therapy. Enrollment began in May 2008 and was completed in May 2010, with the last follow-up visit completed in March 2011. INTERVENTION: Participants were randomly assigned to receive 420-mg silymarin, 700-mg silymarin, or matching placebo administered 3 times per day for 24 weeks. MAIN OUTCOME MEASURES: The primary outcome measure was serum ALT level of 45 U/L or less (considered within the normal range) or less than 65 U/L, provided this was at least a 50% decline from baseline values. Secondary outcomes included changes in ALT levels, HCV RNA levels, and quality-of-life measures. RESULTS: After 24 weeks of treatment, only 2 participants in each treatment group (P ≥ .99) met the primary outcome measure (3.8% [95% CI, 0.5% to 13.2%] for placebo, 4.0% [95% CI, 0.5% to 13.7%] for 420-mg silymarin, and 3.8% [95% CI, 0.5% to 13.2%] for 700-mg silymarin). The mean decline in serum ALT activity at the end of treatment did not differ significantly (P = .75) across the 3 treatment groups (mean decline, -4.3 [95% CI, -17.3 to 8.7] U/L for placebo, -14.4 [95% CI, -41.6 to 12.7] U/L for 420-mg silymarin, -11.3 [95% CI, -27.9 to 5.4] U/L for 700-mg silymarin); there likewise were no significant differences in HCV RNA levels (mean change, 0.07 [95% CI, -0.05 to 0.18] log10 IU/mL for placebo, -0.03 [95% CI, -0.18 to 0.12] log10 IU/mL for 420-mg silymarin, 0.04 [95% CI, -0.08 to 0.16] log10 IU/mL for 700-mg silymarin; P = .54) or quality-of-life measures. The adverse event profile of silymarin was comparable with that of placebo. CONCLUSION: Higher than customary doses of silymarin did not significantly reduce serum ALT levels more than placebo in participants with chronic HCV infection unsuccessfully treated with interferon-based therapy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00680342.

Role of biological therapy for inflammatory bowel disease in developing countries.

Inflammatory bowel disease (IBD) has become a global disease. Its incidence in developing countries is rising. In Asia, this has been attributed to the rapid modernisation and westernisation of the population. As IBD emerges in developing nations, there is a need to reconcile the most appropriate treatment for these patient populations from the perspectives of both disease presentation and cost. In the West, biological agents are the fastest-growing segment of the prescription drug market. They typically cost several thousand to several tens of thousands of dollars per patient per year. The healthcare systems in developing countries will struggle to afford such expensive treatments. Developing countries cover two-thirds of the earth's surface and are home to 3-5 billion inhabitants, constituting three-quarters of all humanity. If IBD emerges to the same extent in those countries as it has in the West, the need for biological therapy will increase dramatically, and the pharmaceutical industry, healthcare providers, patient advocate groups, governments and non-governmental organisations will have to discuss how to handle this. The authors propose that this dialogue should begin now with regard to (1) the major needs of patients with complicated IBD in developing countries, (2) the potential need for biological therapy in developing countries to treat IBD, (3) the necessary infrastructure for selecting patients with IBD who need biological therapy, and (4) medical/ethical issues limiting the use of biological therapy.

Rationale, challenges, and participants in a Phase II trial of a botanical product for chronic hepatitis C.

BACKGROUND: Chronic hepatitis C is associated with significant morbidity and mortality as a consequence of progression to cirrhosis, hepatocellular carcinoma, and liver failure. Current treatment for chronic hepatitis C with pegylated interferon (IFN) and ribavirin is associated with suboptimal responses and numerous adverse effects. A number of botanical products have been used to treat hepatic disorders. Silymarin, extracted from the milk thistle plant, Silybum marianum (L) Gaertn. (Asteraceae), has been most widely used for various liver disorders, including chronic hepatitis C, B, and alcoholic liver disease. However, the safety and efficacy of silymarin have not been studied systematically in chronic hepatitis C. PURPOSE: We describe our strategy for a phased approach for studying the impact of silymarin in hepatitis C, in the context of the unique challenges of botanical product clinical trials and the development of specific and curative antiviral therapy. METHODS: This multicenter, randomized, double-masked, placebo-controlled trial was conducted with four clinical centers and a data-coordinating center in the United States, to assess the impact of silymarin therapy in patients with chronic hepatitis C who failed conventional antiviral therapy. RESULTS: Key aspects relevant to performing clinical trials of botanical products include early identification of an appropriate product with standard product chemistry, acquisition of pharmacokinetic and dosing information, selection of the appropriate study group, and choosing rigorous outcome variables. POTENTIAL LIMITATIONS: Trial participants were chronic hepatitis C patients who were nonsustained virologic responders to IFN-based therapy; therefore, the findings are not generalizable to all hepatitis C populations. Further, alanine aminotransferase, a biochemical liver test, rather than hepatitis viral RNA or liver histology was the primary end point. CONCLUSIONS: The challenges identified and addressed during development of this United States multicenter Phase II trial to evaluate silymarin for treatment of patients with chronic hepatitis C infection who had failed to respond successfully to previous IFN-based therapy are common and must be addressed to conduct rigorous trials of botanical products.

A randomized controlled trial of an integrated care intervention to increase eligibility for chronic hepatitis C treatment.

OBJECTIVES: Mental health and substance abuse (MH/SA) comorbidities are the most oft-cited reasons for deferral from peginterferon (PegIFN) therapy for chronic hepatitis C virus (HCV). We sought to determine whether an integrated care intervention (INT) for patients deferred from PegIFN owing to MH/SA could improve subsequent treatment eligibility rates. METHODS: In this randomized controlled trial, 101 HCV patients who were evaluated at two hepatology centers and deferred from antiviral therapy owing to MH/SA were enrolled. Participants were randomized to an INT (N=50) or standard of care (SC; N=51). The INT group received counseling and case management for up to 9 months. All participants underwent 3-, 6-, and 9-month clinical follow-up visits, where hepatologists, masked to group, re-evaluated patients for treatment eligibility. Standardized mood and alcohol use instruments were administered to all participants to aid clinicians in treatment decisions. RESULTS: Of 101 participants, the mean age was 48 years and 50% were men, 61% Caucasian, and 77% genotype 1. Patients were initially deferred owing to psychiatric issues (35%), alcohol abuse (31%), drug abuse (9%), or more than one of these reasons (26%). In an intent-to-treat analysis, 42% (21/50) of INT participants became eligible for therapy compared to 18% (9/51) of SC participants (P=0.009, relative risk (RR)=2.38, 95% confidence interval (CI) (1.21, 4.68)). When baseline predictors significant at P<0.10 in univariate models were entered into multivariate models adjusted for treatment group, only baseline depression remained significant (P=0.05, RR=0.98, 95% CI (0.96, 1.00)). With the exception of a model adjusted for genotype, treatment group remained significant in all models. CONCLUSIONS: This trial suggests that INTs can increase eligibility for HCV treatment and expand treatment to the underserved population with MH/SA comorbidities.

Visualization and quantification of intestinal transit and motor function by real-time tracking of 19F labeled capsules in humans.

A combined (19)F and (1)H MRI framework for the assessment of human intestinal transit and motor function is presented. This framework consists of silicone coated polychlorotrifluoroethylene capsules filled with perfluoro-[15]-crown-5-ether as (19)F marker, a flexible (19)F surface coil and a (19)F projection imaging sequence, allowing for real-time tracking of a single or multiple capsules. The capsules (length 11.5 mm, Ø 7.2 mm) contain 140 µL perfluoro-[15]-crown-5-ether and were tested for cytotoxicity and leakage prior to oral administration. A balanced SSFP projection sequence was implemented, yielding a temporal resolution of 133 ms. Optional multi-frequency excitation, allowing for interleaved tracking of differently labeled (19)F capsules, was incorporated. The passage of the (19)F capsules through intestinal sections was monitored in two healthy volunteers. Capsule coordinates were successfully coregistered with anatomical reference scans. Intestinal motility, residence times, lengths and forward velocities were determined. Simultaneous tracking of two capsules allowed for the assessment of peristaltic patterns with correction for respiratory motion. By providing the means for real-time multiple capsule tracking and high resolution anatomical imaging, the presented multinuclear imaging framework has the potential to provide important supplemental information for physiological and pharmaceutical research.

Effect on gastric function and symptoms of drinking wine, black tea, or schnapps with a Swiss cheese fondue: randomised controlled crossover trial.

OBJECTIVE: To compare the effects of drinking white wine or black tea with Swiss cheese fondue followed by a shot of cherry schnapps on gastric emptying, appetite, and abdominal symptoms. DESIGN: Randomised controlled crossover study. PARTICIPANTS: 20 healthy adults (14 men) aged 23-58. INTERVENTIONS: Cheese fondue (3260 kJ, 32% fat) labelled with 150 mg sodium (13)Carbon-octanoate was consumed with 300 ml of white wine (13%, 40 g alcohol) or black tea in randomised order, followed by 20 ml schnapps (40%, 8 g alcohol) or water in randomised order. MAIN OUTCOME MEASURES: Cumulative percentage dose of (13)C substrate recovered over four hours (higher values indicate faster gastric emptying) and appetite and dyspeptic symptoms (visual analogue scales). RESULTS: Gastric emptying was significantly faster when fondue was consumed with tea or water than with wine or schnapps (cumulative percentage dose of (13)C recovered 18.1%, 95% confidence interval 15.2% to 20.9% v 7.4%, 4.6% to 10.3%; P<0.001). An inverse dose-response relation between alcohol intake and gastric emptying was evident. Appetite was similar with consumption of wine or tea (difference 0.11, -0.12 to 0.34; P=0.35), but reduced if both wine and schnapps were consumed (difference -0.40, -0.01 to -0.79; P<0.046). No difference in dyspeptic symptoms was present. CONCLUSIONS: Gastric emptying after a Swiss cheese fondue is noticeably slower and appetite suppressed if consumed with higher doses of alcohol. This effect was not associated with dyspeptic symptoms. TRIAL REGISTRATION: ClinicalTrials.gov NCT00943696.

Prevalence of anaemia in inflammatory bowel disease in Switzerland: a cross-sectional study in patients from private practices and university hospitals.

BACKGROUND: Anaemia represents a common complication of inflammatory bowel disease (IBD). Most studies on anaemia in IBD patients have been performed in tertiary referral centres (RC) and data from gastroenterologic practices (GP) are lacking. We investigated the frequency and severity of anaemia in IBD patients from tertiary referral centres and gastroenterologic practices compared to the general population. METHODS: Data were acquired from patients included in the Swiss IBD Cohort Study. IBD activity was evaluated by CDAI and modified Truelove and Witts severity index (MTWSI). Anaemia was defined as haemoglobin ≤120g/L in women and ≤130g/L in men. RESULTS: 125 patients from RC (66 with Crohn's disease (CD) and 59 with ulcerative colitis (UC)) and 116 patients from GP (71 CD and 45 UC) were included and compared to 6074 blood donors. Anaemia was found in 21.2% (51/241) of the IBD patients and more frequently in patients from RC as compared to GP and healthy controls (28.8% vs. 12.9% vs. 3.4%; P<0.01). IBD patients from RC suffered more frequently from active disease compared to IBD patients in GP (36% vs. 23%, P=0.032). Supplementation therapy (iron, vitamin B12, folic acid) was performed in 40% of anaemic IBD patients in GP as compared to 43% in RC. CONCLUSIONS: Anaemia is a common complication in patients with IBD and significantly more prevalent in patients from referral centres as compared to patients from gastroenterologic practices. Physicians treating IBD patients should pay attention to the presence of anaemia and ensure sufficient supplementation therapy.

Effect of a prebiotic mixture on intestinal comfort and general wellbeing in health.

Specific carbohydrates, i.e. prebiotics such as fructo-oligosaccharide (FOS), are not digested in the small intestine but fermented in the colon. Besides beneficial health effects of an enhanced bifidobacteria population, intestinal gas production resulting from fermentation can induce abdominal symptoms. Partial replacement with slowly fermented acacia gum may attenuate side effects. The aim was to compare the effects of FOS with those of a prebiotic mixture (50 % FOS and 50 % acacia gum; BLEND) and a rapidly absorbed carbohydrate (maltodextrin) on general intestinal wellbeing, abdominal comfort and anorectal sensory function. Twenty volunteers (eight male and twelve female; age 20-37 years) completed this double-blind, randomised study with two cycles of a 2-week run-in phase (10 g maltodextrin) followed by 5 weeks of 10 g FOS or BLEND once daily, separated by a 4-week wash-out interval. Abdominal symptoms and general wellbeing were documented by telephone interview or Internet twice weekly. Rectal sensations were assessed by a visual analogue scale during a rectal barostat test after FOS and BLEND treatment. Both FOS and BLEND induced more side effects than maltodextrin. Belching was more pronounced under FOS compared with BLEND (P = 0.09 for females; P = 0.01 for males), and for self-reported general wellbeing strong sex differences were reported (P = 0.002). Urgency scores during rectal barostat were higher with FOS than BLEND (P = 0.01). Faced with a growing range of supplemented food products, consumers may benefit from prebiotic mixtures which cause fewer abdominal side effects. Sex differences must be taken in consideration when food supplements are used.

Pharmacokinetics and metabolic profile of free, conjugated, and total silymarin flavonolignans in human plasma after oral administration of milk thistle extract.

Silymarin, a mixture of polyphenolic flavonoids extracted from milk thistle (Silybum marianum), is composed mainly of silychristin, silydianin, silybin A, silybin B (SB(B)), isosilybin A (ISB(A)), and isosilybin B. In this study, the plasma concentrations of free (unconjugated), conjugated (sulfated and glucuronidated), and total (free and conjugated) silymarin flavonolignans were measured using liquid chromatography-electrospray ionization-mass spectrometry, after a single oral dose of 600 mg of standardized milk thistle extracts to three healthy volunteers. Pharmacokinetic analysis indicated that silymarin flavonolignans were rapidly eliminated with short half-lives (1-3 and 3-8 h for free and conjugated, respectively). The AUC(0-->infinity) values of the conjugated silymarin flavonolignans were 4- to 30-fold higher than those of their free fractions, with SB(B) (mean AUC(0-->infinity) = 51 and 597 microg x h/l for free and conjugated, respectively) and ISB(A) (mean AUC(0-->infinity) = 30 and 734 microg x h/l for free and conjugated, respectively) exhibiting higher AUC(0-->infinity) values in comparison with other flavonolignans. Near the plasma peak times (1-3 h), the free, sulfated, and glucuronidated flavonolignans represented approximately 17, 28, and 55% of the total silymarin, respectively. In addition, the individual silymarin flavonolignans exhibited quite different plasma profiles for both the free and conjugated fractions. These data suggest that, after oral administration, silymarin flavonolignans are quickly metabolized to their conjugates, primarily forming glucuronides, and the conjugates are primary components present in human plasma.

The physical properties of rectal contents have effects on anorectal continence: insights from a study into the cause of fecal spotting on orlistat.

PURPOSE: The intermittent loss of oil or stool ("spotting") is an adverse effect that occurs in patients taking orlistat; the pathophysiology is unknown. This study was designed to investigate the local effects of orlistat, free fatty acids, and the effects of the physical properties of rectal contents on anorectal function and continence. METHODS: Anorectal physiology and continence function were assessed in ten healthy patients after the application of four test enemas: 1) high-viscosity stool substitute, 2) stool substitute with free fatty acid, 3) low-viscosity oil with placebo, 4) oil with orlistat. Rectal function and capacity were assessed by barostat techniques. Anal resting pressure, squeeze pressure, and squeeze duration were assessed by manometry. A retention test was performed using the same enemas as a quantitative assessment of continence. RESULTS: Orlistat and free fatty acid had no adverse effects on anorectal function or continence. For each enema, the maximum volume retained correlated with rectal capacity (r = 0.85; P < 0.01). Continence during rectal filling was better maintained for high-viscosity stool substitute than low-viscosity oil enemas (P < 0.03). Patients able to maintain effective squeeze pressure retained more of the low-viscosity enemas than those with short squeeze duration (P < 0.01); in contrast, the volume retained of high-viscosity enemas was unaffected by anal sphincter function. CONCLUSIONS: The physical properties of rectal contents, rectal capacity, and voluntary anal sphincter function have effects on continence function in healthy patients. The occurrence of spotting may depend on both intrinsic anorectal function and the effects of orlistat on the volume and physical properties of stool.

Effects of zinc occupancy on human O6-alkylguanine-DNA alkyltransferase.

A recent crystallographic study of recombinant human O(6)-alkylguanine-DNA alkyltransferase (hAGT) revealed a previously unknown zinc atom [Daniels et al., (2000) EMBO J. 19, 1719-1730]. The effects of zinc on the properties of hAGT are reported here. In bacterial expression systems, recombinant hAGT was produced in increasingly larger quantities when growth media are supplemented with up to 0.1 mM ZnCl(2). Metal-enriched hAGT samples had a 5-fold increase in repair rate constant over conventionally purified protein samples and a 60-fold increase over metal-stripped hAGT. In addition, mutants of the zinc-binding residues had decreases in zinc occupancy that correlated with reductions in repair rate. Zinc modulation did not abolish the repair capacity of a fraction of the hAGT population, as evidenced by the stoichiometric reaction with an oligodeoxyribonucleotide substrate. Zinc occupancy had a similar effect on the rate of reaction with O(6)-benzylguanine, a free base substrate, as on the repair of methylated DNA. Differentially zinc-treated hAGTs showed the same affinity for binding to native DNA and substrate oligodeoxyribonucleotides. Metal content manipulations had little effect upon the CD spectrum of hAGT, but fluorescence studies revealed a small conformational change based upon metal binding, and zinc occupancy correlated with enhanced hAGT stability as evidenced by resistance to the denaturing effects of urea. These results indicate that the presence of zinc confers a mechanistic enhancement to repair activity that does not result from an increase in substrate binding affinity. Zinc also provides conformational stability to hAGT that may influence its regulation.

Dehydroepiandrosterone (DHEA) modulates the activity and the expression of lymphocyte subpopulations induced by cecal ligation and puncture.

Dehydroepiandrosterone (DHEA) exerts a variety of positive effects on the immunologic alterations after trauma and sepsis. We therefore measured the therapeutic efficacy of DHEA after cecal ligation and puncture (CLP) on the expression of lymphocyte subpopulations and on the delayed type hypersensitivity (DTH) reaction. Male NMRI-mice were randomly assigned to four different treatment groups. Treatment consisted of DHEA or saline (S) administration after CLP or laparotomy only. Flow cytometry was performed (CD4+, CD8+, and CD56 lymphocytes) after 96 hours. DTH-reaction, activity and mortality rate were documented. The CLP-induced reduction in activity and survival (mortality: 34/40) was significantly (p < 0.03) less sustained in CLP-DHEA (mortality: 22/40). The DTH-ratio (before vs. after secondary challenge) was significantly lowered in CLP-S (1.01 +/- 0.15) compared to CLP-DHEA (1.35 +/- 0.1) after 48 hours (p < 0.01). CLP-DHEA (22.2 +/- 7.9%) was associated with a statistically significant less sustained increase of CD56+ cells (p < 0.01) compared with CLP-S (49.0 +/- 6.9%). DHEA-treatment after CLP was associated with less reduction in the CD8+ T-lymphocyte subsets (p < 0.01 vs. all other groups). DHEA treatment after CLP was associated with fewer alterations in the changes of CD8+ and CD56, cells, and the DTH reaction compared with animals submitted to CLP without any treatment. This difference was associated with improved outcome (reactivity, mortality). These results suggest a modulation at specific immune reactions by DHEA treatment.