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The gut microbiota plays an important role in regulating the pharmacokinetics and pharmacodynamics of many drugs. FLZ, a novel squamosamide derivative, has been shown to have neuroprotective effects on experimental Parkinson's disease (PD) models. FLZ is under phase Ⅰ clinical trial now, while the underlying mechanisms contributing to the absorption of FLZ are still not fully elucidated. Due to the main metabolite of FLZ was abundant in feces but rare in urine and bile of mice, we focused on the gut microbiota to address how FLZ was metabolized and absorbed. In vitro studies revealed that FLZ could be exclusively metabolized to its major metabolite M1 by the lanosterol 14 alpha-demethylase (CYP51) in the gut microbiota, but was almost not metabolized by any other metabolism-related organs, such as liver, kidney, and small intestine. M1 was quickly absorbed into the blood and then remethylated to FLZ by catechol O -methyltransferase (COMT). Notably, dysbacteriosis reduced the therapeutic efficacy of FLZ on the PD mouse model by inhibiting its absorption. The results show that the gut microbiota mediate the absorption of FLZ through a FLZ–M1–FLZ circulation. Our research elucidates the vital role of the gut microbiota in the absorption of FLZ and provides a theoretical basis for clinical pharmacokinetic studies and clinical application of FLZ in the treatment of PD. This study elucidates the role of gut microbiota in absorption of FLZ, a novel neuroprotective squamosamide derivative, providing theoretical basis for its clinical application in the treatment of Parkinson's disease. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Parenteral nutrition (PN) is the main treatment for intestinal failure. Objective: We aimed to review the indications for home parenteral nutrition (HPN) in children and describe the outcome over a 14-y period from a single center. Design: We conducted a retrospective study that included all children who were referred to our institution and discharged while receiving HPN between 1 January 2000 and 31 December 2013. The indications for HPN were divided into primary digestive diseases (PDDs) and primary nondigestive diseases (PNDDs). We compared our results to a previous study that was performed in our unit from 1980 to 2000 and included 302 patients. Results: A total of 251 patients were included: 217 (86%) had a PDD. The mean ± SD age at HPN onset was 0.7 ± 0.3 y, with a mean duration of 1.9 ± 0.4 y. The indications for HPN were short bowel syndrome (SBS) (59%), PNDD (14%), congenital enteropathies (10%), chronic intestinal pseudo-obstruction syndromes (9%), inflammatory bowel diseases (5%), and other digestive diseases (3%). By 31 December 2013, 52% of children were weaned off of HPN, 9% of the PDD subgroup had intestinal transplantation, and 10% died mostly because of immune deficiency. The major complications of HPN were catheter-related bloodstream infections (CRBSIs) (1.7/1000 d of PN) and intestinal failure-associated liver disease (IFALD) (51 children; 20% of cohort). An increased rate of CRBSIs was observed compared with our previous study, but we saw a decreasing trend since 2012. No noteworthy deceleration of growth was observed in SBS children 6 mo after weaning off HPN. Conclusions: SBS was the major indication for HPN in our cohort. IFALD and CRBSIs were potentially life-threatening problems. Nevertheless, complication rates were low, and deaths resulted mostly from the underlying disease. [ABSTRACT FROM AUTHOR]

Background: Benefits of recombinant human growth hormone (rhGH) alone or combined with glutamine in patients with intestinal failure because of short-bowel syndrome remain controversial. Objective: We explored effects of rhGH on whole-body protein metabolism in patients with short-bowel syndrome with intestinal failure (SBS-IF) to gain insight into its mechanism of action. Design: Eight stable hyperphagic patients with severe SBS-IF received, in a double-blind, randomized crossover study, low-dose rhGH (0.05 mg · kg-1· d-1) and a placebo for two 3-wk periods. Leucine and glutamine kinetics under fasting and fed conditions, fat-free mass (FFM), and serum insulin were determined on the final day of each treatment. Results: rhGH increased FFM and nonoxidative leucine disposal (NOLD; an index of protein synthesis) (P < 0.02), whereas FFM and NOLD were correlated in the fed state (r = 0.81, P = 0.015). With rhGH administration, leucine release from protein breakdown (an index of proteolysis) decreased in the fed compared with fasting states (P = 0.012), which was not observed with the placebo. However, the fast-to-fed difference in leucine release from protein breakdown was not significantly different between rhGH and placebo (P = 0.093). With rhGH, the intestinal absorption of leucine and glutamine increased (P = 0.036) and correlated with serum insulin (r = 0.91, P = 0.002). rhGH increased glutamine de novo synthesis (P< 0.02) and plasma concentrations (P < 0.03) in both fasting and fed states. Conclusions: In SBS-IF patients, feeding fails to decrease proteolysis in contrast to what is physiologically observed in healthy subjects. rhGH enhances FFM through the stimulation of protein synthesis and might decrease proteolysis in response to feeding. Improvements in de novo synthesis and intestinal absorption increase glutamine availability over the physiologic range, suggesting that beneficial effects of rhGH in hyperphagic patients might be achieved without glutamine supplementation. [ABSTRACT FROM AUTHOR]

Short bowel syndrome (SBS) results from the loss of a highly specialized organ, the small intestine. SBS and its current treatments are associated with high morbidity and mortality. Production of tissue-engineered small intestine (TESI) from the patient''s own cells could restore normal intestinal function via autologous transplantation. Improved understanding of intestinal stem cells and their niche have been coupled with advances in tissue engineering techniques. Originally described by Vacanti et al of Massachusetts General Hospital, TESI has been produced by in vivo implantation of organoid units. Organoid units are multicellular clusters of epithelium and mesenchyme that may be harvested from native intestine. These clusters are loaded onto a scaffold and implanted into the host omentum. The scaffold provides physical support that permits angiogenesis and vasculogenesis of the developing tissue. After a period of 4 weeks, histologic analyses confirm the similarity of TESI to native intestine. TESI contains a differentiated epithelium, mesenchyme, blood vessels, muscle, and nerve components. To date, similar experiments have proved successful in rat, mouse, and pig models. Additional experiments have shown clinical improvement and rescue of SBS rats after implantation of TESI. In comparison with the group that underwent massive enterectomy alone, rats that had surgical anastomosis of TESI to their shortened intestine showed improvement in postoperative weight gain and serum B12 values. Recently, organoid units have been harvested from human intestinal samples and successfully grown into TESI by using an immunodeficient mouse host. Current TESI production yields approximately 3 times the number of cells initially implanted, but improvements in the scaffold and blood supply are being developed in efforts to increase TESI size. Exciting new techniques in stem cell biology and directed cellular differentiation may generate additional sources of autologous intestinal tissue for direct translation to human therapy. [Copyright &y& Elsevier]

Abstract: Objectives: The purpose of this systematic review was to assess the efficacy of growth hormone (GH) treatment in patients with short bowel syndrome (SBS). Methods: Electronic searches were performed to identify all publications describing randomized controlled trials (RCTs) on the use of GH with or without glutamine for the treatment of patients with SBS. The outcomes of interest were body weight, lean body mass, and intestinal absorption function. Results: Four trials involving 70 patients were included in the review. A meta-analysis of these trials suggested that GH had a positive effect in terms of increased weight (mean difference [MD] = 1.66; 95% CI, 0.69–2.63, P < 0.001), lean body mass (MD = 1.93; 95% CI, 0.97–2.90; P < 0.001), energy absorption (MD = 4.42; 95% CI, 0.26–8.58; P = 0.04), nitrogen absorption (MD = 4.85; 95% CI, 0.20–9.49; P = 0.04), and fat absorption (MD = 5.02; 95% CI, 0.21–9.82; P = 0.04) for patients with SBS. Adverse effects occurred during active treatment in all trials. Only 1 trial included a 12-week follow-up study. Conclusions: The results suggest a possible short-term benefit in terms of body weight, lean body mass, and absorptive capacities; however, no conclusion of long-term efficacy of GH could be obtained. Large-scale, long-term follow-up RCTs are needed to confirm the efficacy and tolerability of GH in the future. [Copyright &y& Elsevier]