On the biosynthesis of specialized pro-resolving mediators in human neutrophils and the influence of cell integrity.

Neutrophils are key players in inflammation initiation and resolution. Little attention has been paid to the detailed biosynthesis of specialized pro-resolving mediators (SPM) in these cells. We investigated SPM formation in human polymorphonuclear leukocytes (PMNL), in broken PMNL preparations and recombinant human 5-lipoxygenase (5-LO) supplemented with the SPM precursor lipids 15-Hydroxyeicosatetraenoic acid (15-HETE), 18-Hydroxyeicosapentaenoic acid (18-HEPE) or 17-Hydroxydocosahexaenoic acid (17-HDHA). In addition, the influence of 5-LO activating protein (FLAP) inhibition on SPM formation in PMNL was assessed. Intact human PMNL preferred ARA over DHA for lipid mediator formation. In contrast, in incubations supplemented with the SPM precursor lipids DHA-derived 17-HDHA was preferred over 15-HETE and 18-HEPE. SPM formation in the cells was dominated by 5(S),15(S)-diHETE (800 pmol/20 mio cells) and Resolvin D5 (2300 pmol/20 mio cells). Formation of lipoxins (<10 pmol/20 mio cells), E-series (<70 pmol/20 mio cells) and other D-series resolvins (<20 pmol/20 mio cells) was low and only detected after addition of the precursor lipids. Upon destruction of cell integrity, formation of lipoxins and 5(S),15(S)-diHETE increased while formation of 17-HDHA- and 18-HEPE-derived SPMs was attenuated. Recombinant 5-LO did not accept the precursors for SPM formation and FLAP inhibition prevented the formation of the 5-LO-dependent SPMs. Together with the data on FLAP inhibition our results point to unknown factors that control SPM formation in human neutrophils and also render lipoxin and 5(S),15(S)-diHETE formation independent of membrane association and FLAP when cellular integrity is destroyed.

Alox12/15 Deficiency Exacerbates, While Lipoxin A4 Ameliorates Hepatic Inflammation in Murine Alcoholic Hepatitis.

Alcoholism is one of the leading and increasingly prevalent reasons of liver associated morbidity and mortality worldwide. Alcoholic hepatitis (AH) constitutes a severe disease with currently no satisfying treatment options. Lipoxin A4 (LXA4), a 15-lipoxygenase (ALOX15)-dependent lipid mediator involved in resolution of inflammation, showed promising pre-clinical results in the therapy of several inflammatory diseases. Since inflammation is a main driver of disease progression in alcoholic hepatitis, we investigated the impact of endogenous ALOX15-dependent lipid mediators and exogenously applied LXA4 on AH development. A mouse model for alcoholic steatohepatitis (NIAAA model) was tested in Alox12/15+/+ and Alox12/15-/- mice, with or without supplementation of LXA4. Absence of Alox12/15 aggravated parameters of liver disease, increased hepatic immune cell infiltration in AH, and elevated systemic neutrophils as a marker for systemic inflammation. Interestingly, i.p. injections of LXA4 significantly lowered transaminase levels only in Alox12/15-/- mice and reduced hepatic immune cell infiltration as well as systemic inflammatory cytokine expression in both genotypes, even though steatosis progressed. Thus, while LXA4 injection attenuated selected parameters of disease progression in Alox12/15-/- mice, its beneficial impact on immunity was also apparent in Alox12/15+/+ mice. In conclusion, pro-resolving lipid mediators may be beneficial to reduce inflammation in alcoholic hepatitis.

Sorafenib Treatment and Modulation of the Sphingolipid Pathway Affect Proliferation and Viability of Hepatocellular Carcinoma In Vitro.

Hepatocellular carcinoma (HCC) shows a remarkable heterogeneity and is recognized as a chemoresistant tumor with dismal prognosis. In previous studies, we observed significant alterations in the serum sphingolipids of patients with HCC. This study aimed to investigate the in vitro effects of sorafenib, which is the most widely used systemic HCC medication, on the sphingolipid pathway as well as the effects of inhibiting the sphingolipid pathway in HCC. Huh7.5 and HepG2 cells were stimulated with sorafenib, and inhibitors of the sphingolipid pathway and cell proliferation, viability, and concentrations of bioactive metabolites were assessed. We observed a significant downregulation of cell proliferation and viability and a simultaneous upregulation of dihydroceramides upon sorafenib stimulation. Interestingly, fumonisin B1 (FB1) and the general sphingosine kinase inhibitor SKI II were able to inhibit cell proliferation more prominently in HepG2 and Huh7.5 cells, whereas there were no consistent effects on the formation of dihydroceramides, thus implying an involvement of distinct metabolic pathways. In conclusion, our study demonstrates a significant downregulation of HCC proliferation upon sorafenib, FB1, and SKI II treatment, whereas it seems they exert antiproliferative effects independently from sphingolipids. Certainly, further data would be required to elucidate the potential of FB1 and SKI II as putative novel therapeutic targets in HCC.

Real World Performance of Sacral Neuromodulation and OnabotulinumtoxinA for Overactive Bladder: Focus on Safety and Cost.

PURPOSE: We aimed to determine the real world safety and cost of third line overactive bladder therapies, including onabotulinumtoxinA and sacral neuromodulation. MATERIALS AND METHODS: We performed an all-inclusive, population based cohort study of third line therapies of overactive bladder (sacral neuromodulation or onabotulinumtoxinA) using the statewide surgical data captured in the New York Statewide Planning and Research Cooperative System. The main outcome measures were 30-day safety events, and 1 and 3-year health care utilization costs. Propensity score matching was done to control for confounding factors and comparative analyses of safety events were also performed. RESULTS: Our cohort included 2,680 patients, of whom 1,328 underwent sacral neuromodulation and 1,352 received onabotulinumtoxinA from January 1, 2013 through December 31, 2016. Average ± SD age was 61.7 ± 16.3 years and 82.7% of the patients were female. Sacral neuromodulation implantation led to re-intervention in 15.8% of cases within 1 year and in 26.1% at 3 years. In this comparative analysis patients who received onabotulinumtoxinA therapy were at higher risk for urinary tract infection, hematuria, urinary retention and an emergency room visit compared to those treated with sacral neuromodulation. The overall cost of onabotulinumtoxinA was lower than the cost of the sacral neuromodulation device (cost at 1 year $2,896 vs $15,343 and at 3 years $3,454 vs $16,189, each p <0.01). CONCLUSIONS: Sacral neuromodulation implantation was more expensive than onabotulinumtoxinA injection. However, patients who underwent sacral neuromodulation had a lower complication rate than patients treated with onabotulinumtoxinA. A quality improvement collective database must be created to track information on onabotulinumtoxinA and sacral neuromodulation treatment. This would help generate better performance and comparative data for patient and physician decision making.

Ejaculatory Preserving Middle Lobe Onl-Transurethral Resection and Vaporization of the Prostate: 12-Year Experience.

OBJECTIVE: To report long-term safety and efficacy data on middle lobe only-transurethral resection of the prostate (TURP) (MLO-TURP). MATERIALS AND METHODS: We evaluated: (1) efficacy: International Prostate Symptom Score, Quality of Life, peak flow rate (Qmax), postvoid residual urine, International Index of Erectile Function and ejaculatory function, which was assessed by the Male Sexual Health Questionnaire. Men were evaluated at 1 month, 6 months, and yearly thereafter. RESULTS: A total 312 men (mean age 61.3 ± 8.6) with significant lower urinary tract symptoms (n = 147) or urinary retention (n = 175 were treated with MLO-TURP from 2005 to 2017. Mean baseline prostate volume was 79.8 g (30-178 g); mean baseline intravesical-prostatic protrusion was 13.6. Improvements in International Prostate Symptom Score, Quality of Life, Qmax and postvoid residual urine were durable throughout the study period. There was no difference in outcomes between monopolar and bipolar MLO-TURPs. Postoperatively, the incidence of ejaculatory dysfunction was 2.6% (N = 8) and there was 1 case of new onset ED (0.3%). There were modest improvement in bother due to ejaculatory function (baseline: 2.4 and at 5 years: 1.27). CONCLUSION: MLO-TURP is a safe and effective treatment for men with lower urinary tract symptoms. Patients experience long-term improvement of symptoms and preserve antegrade ejaculation. In select men with prominent middle lobes, MLO-- should be considered a therapeutic, ejaculation-sparing option.

Omega-3 and -6 fatty acid plasma levels are not associated with liver cirrhosis-associated systemic inflammation.

BACKGROUND: Liver cirrhosis is associated with profound immunodysfunction, i.e. a parallel presence of chronic systemic inflammation and immunosuppression, which can result in acute-on-chronic liver failure (ACLF). Omega-3 fatty acids are precursors of pro-resolving mediators and support the resolution of inflammation. OBJECTIVE: The aim of this study was to determine plasma levels of omega-3 fatty acids in patients with liver cirrhosis and ACLF. METHODS: Patients with liver cirrhosis with and without ACLF were enrolled in a prospective cohort study and analyzed post-hoc for the present sub-study. Clinical data and biomaterials were collected at baseline and at day 7, 28 and after 3 months of follow-up. Plasma concentrations of arachidonic acid (ARA) and docosahexaenoic acid (DHA), which represent key omega-6 and -3 fatty acids, respectively, were quantified and associated with markers of systemic inflammation and severity of liver cirrhosis. RESULTS: A total of 117 patients were included in the present analyses. Of those, 26 (22.2%), 51 (43.6%) and 40 (34.2%) patients had compensated or decompensated liver cirrhosis, and ACLF. Plasma levels of ARA and DHA were similar in patients with compensated cirrhosis, decompensated cirrhosis, and ACLF. Furthermore, no significant association between plasma ARA or DHA and C-reactive protein or peripheral blood leukocytes were observed (P>0.05). CONCLUSION: In our study plasma levels of key omega-3 and omega-6 fatty acid are neither associated with the severity of liver cirrhosis nor with liver-cirrhosis-associated systemic inflammation.

The oxidized linoleic acid metabolite 12,13-DiHOME mediates thermal hyperalgesia during inflammatory pain.

Eicosanoids play a crucial role in inflammatory pain. However, there is very little knowledge about the contribution of oxidized linoleic acid metabolites in inflammatory pain and peripheral sensitization. Here, we identify 12,13-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME), a cytochrome P450-derived linoleic acid metabolite, as crucial mediator of thermal hyperalgesia during inflammatory pain. We found 12,13-DiHOME in increased concentrations in peripheral nervous tissue during acute zymosan- and complete Freund's Adjuvant-induced inflammatory pain. 12,13-DiHOME causes calcium transients in sensory neurons and sensitizes the transient receptor potential vanilloid 1 (TRPV1)-mediated intracellular calcium increases via protein kinase C, subsequently leading to enhanced TRPV1-dependent CGRP-release from sensory neurons. Peripheral injection of 12,13-DiHOME in vivo causes TRPV1-dependent thermal pain hypersensitivity. Finally, application of the soluble epoxide hydrolase (sEH)-inhibitor TPPU reduces 12,13-DiHOME concentrations in nervous tissue and reduces zymosan- and CFA-induced thermal hyperalgesia in vivo. In conclusion, we identify a novel role for the lipid mediator 12,13-DiHOME in mediating thermal hyperalgesia during inflammatory pain and propose a novel mechanism that may explain the antihyperalgesic effects of sEH inhibitors in vivo.

Trends and Clinical Practice Patterns of Sacral Neuromodulation for Overactive Bladder.

OBJECTIVES: The aim of this study was to investigate surgical practice patterns of American urologists treating refractory overactive bladder (OAB) over the past decade. Refractory OAB remains a management challenge to urologists. When multiple medical therapies have failed, treatment options may include sacral neuromodulation (SNM) or surgery such as augmentation cystoplasty (AC). METHODS: Data on SNM and AC performed between 2003 and 2012 by certifying and recertifying urologists were obtained in the form of annualized case logs from the American Board of Urology (ABU). Associations between surgeon characteristics (type of certification, annual volume, practice type, and location) and these procedures were evaluated. RESULTS: Over the past decade, 756 of 6355 urologists certified with the ABU performed SNM or AC for the treatment of refractory OAB. Forty-five (6%) of these surgeons completed fellowships in female urology and 71 surgeons (9%) completed another type of fellowship program. Surgeons recertifying with ABU performed 76% of all SNM procedures. Although SNM and AC have increased from 64 to 2086 between 2003 and 2012, however, this is mainly driven by the increase of SNM from 48 to 2068 cases. Rates of AC have remained stable with 14 to 38 cases reported annually. However, they have declined relative to the total, from 25% in 2003 to less than 1% in 2012. CONCLUSIONS: Sacral neuromodulation has increased dramatically over the past decade in surgeons certified with the ABU. This is in contrast to AC, which while remaining stable in number of procedures.

Vitamin D Supplementation Enhances C18(dihydro)ceramide Levels in Type 2 Diabetes Patients.

Sphingolipids are characterized by a broad range of bioactive properties. Particularly, the development of insulin resistance, a major pathophysiological hallmark of Type 2 Diabetes mellitus (T2D), has been linked to ceramide signaling. Since vitamin D supplementation may slow down T2D progression by improving glucose concentrations and insulin sensitivity, we investigated whether vitamin D supplementation impacts on plasma sphingolipid levels in T2D patients. Thus, plasma samples of 59 patients with non-insulin-requiring T2D from a placebo-controlled, randomized, and double-blind study were retrospectively analyzed. Once per week, patients received either 20 drops of Vigantol oil, corresponding to a daily dose of 1904 IU/d vitamin D (verum: n = 31), or a placebo oil consisting of medium chain triglycerides (placebo: n = 28). Blood samples were taken from all of the participants at three different time points: 1) at the beginning of the study (baseline), 2) after 6 months supplementation, and 3) after an additional 6 months of follow-up. Plasma sphingolipids were measured by high-performance liquid chromatography tandem mass spectrometry. At baseline and 6 months follow-up, no significant differences in plasma sphingolipid species were detected between the placebo and verum groups. After 6 months, vitamin D supplementation significantly enhanced plasma C18dihydroceramide (dhCer; N-stearoyl-sphinganine (d18:0/18:0)) and C18ceramide (Cer; N-stearoyl-sphingosine (d18:1/18:0)) levels were observed in the verum group compared to the placebo group. This was accompanied by significantly higher 25-hydroxyvitamin D3 (25(OH)D3) blood levels in patients receiving vitamin D compared to the placebo group. Taken together, vitamin D supplementation induced changes of the C18 chain-length-specific dhCer and Cer plasma levels in patients with T2D. The regulation of sphingolipid signaling by vitamin D may thus unravel a novel mechanism by which vitamin D can influence glucose utilization and insulin action. Whether this acts favorably or unfavorably for the progression of T2D needs to be clarified.