Polyphenol extract from evening primrose pomace alleviates experimental colitis after intracolonic and oral administration in mice

Oenothera paradoxa (EP) preparations are commonly used in folk medicine to treat skin diseases, neuralgia, and gastrointestinal (GI) disorders. Several reports suggested that EP preparations exhibit potent anti-inflammatory and antioxidant activities both in vitro and in vivo. Here, we aimed to characterize the action of EP pomace polyphenol extract in mouse model of colitis. We analyzed the composition of EP pomace polyphenol extract using reversed phase HPLC system and ultra-performance liquid chromatography (UPLC) system coupled with a quadrupole-time of flight (Q-TOF) MS instrument. Then, we used a well-established animal model of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis to determine the anti-inflammatory action of EP pomace polyphenol extract. We also investigated the effect of the EP pomace polyphenol extract on pro-inflammatory (IL-1β and TNF-α) cytokine mRNA levels and hydrogen peroxide concentration in the inflamed colon. Administration of EP pomace polyphenol extract significantly improved macroscopic and microscopic damage scores, as well as myeloperoxidase (MPO) activity in TNBS-treated mice. The anti-inflammatory effect of the extract was observed after intracolonic and oral administration and was dose-dependent. Significant reduction of tissue hydrogen peroxide level after treatment with EP pomace polyphenol extract suggests that its therapeutic effect is a result of free radical scavenging. This novel finding indicates that the application of the EP pomace polyphenol extract in patients with inflammatory bowel diseases (IBDs) may become an attractive supplementary treatment for conventional anti-inflammatory therapy.The authors wish to thank Dr. Alicja Z. Kucharska from the Wroclaw University of Environmental and Life Sciences for determining the composition of polyphenolic compounds by UPLC-QTOF-MS. This study was supported by the bilateral cooperation between Poland and China, the Iuventus Plus program of the Polish Ministry of Science and Higher Education (0107/IP1/2013/72 to JF), and Medical University of Lodz (502-03/1-156-02/502-14-140 to M Sałaga and 503/ 1-156-04/503-01)

Effect of suramin on urinary excretion of diabetes-induced glomerular and tubular injury parameters in rats

Diabetes mellitus causes changes in metabolism of extracellular nucleotides acting through P2 receptors (P2Rs). This affects renal function and may lead to glomerular and tubular disturbances. We measured urinary excretion of nucleotides (ATP, ADP, AMP, UTP, UDP, UMP) in streptozotocin-induced diabetic rats (65 mg/kg, i.p., day 0) and the effects of P2Rs' blockade by suramin (10 mg/kg, i.p., days +7, +14) on glomerular P2×7R expression and urinary excretion of glomerular (albumin, nephrin) and tubular (KIM-1, NGAL) injury markers, electrolytes, and oxidative stress markers (TBARS, 8-OHdG). Concentrations of nucleotides, specific proteins, electrolytes, and oxidative stress markers in 24-h urine samples collected in metabolic cages at days -1, +6 and +20 were measured using ion-paired reversed-phase HPLC, immunoenzymatic and fluorometric methods, and flame photometry, respectively. Expression of KIM-1 and P2×7R was examined by immunohistochemistry or immunoblotting. Diabetes was associated with increased urinary excretion of ATP, ADP, UTP, UDP and glomerular P2×7R expression. Suramin attenuated P2×7R expression but did not affect urinary excretion of nucleotides. Urinary excretion of albumin, nephrin, NGAL, and 8-OHdG were increased in diabetic rats and were not affected by suramin. TBARS was higher in diabetic rats and suramin attenuated the excretion dynamics in this group. KIM-1 excretion was higher in diabetic rats and suramin further increased excretion of KIM-1 in both diabetic and non-diabetic rats. Furthermore, suramin attenuated the diabetes-induced natriuresis and kaliuresis. It is possible that suramin affects both glomerular and tubular functions in diabetic rats

Endocannabinoid and cannabinoid-like fatty acid amide levels correlate with pain-related symptoms in patients with IBS-D and IBS-C: a pilot study.

AIMS: Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS) was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. METHODS: AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D) and constipation-predominant (IBS-C) patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. RESULTS: Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. CONCLUSION: IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms