Inhibition Of Prostaglandin Synthesis Research Articles

THE EFFECT OF ACETYLSALICYLIC ACID ON INTENSTITY OF BOLD SIGNAL IN HUMAN VISUAL CORTEX DURING VIDEO STIMULATION. FMRI STUDY

It was found that repeated excitation and the use of aspirin as an inhibitor of prostaglandin synthesis did not affect level of BOLD signal in visual cortex. It was found a decrease in hemodynamic response to visual stimulation in thalamus under the influence of aspirin.

Induction of right open reading frame kinase 3 (RIOK3) during ovulation and luteinisation in rat ovary.

Atypical protein serine kinase RIOK3 is involved in cellular invasion and survival. The spatiotemporal expression pattern and regulatory mechanisms controlling expression of Riok3 were investigated in the rat ovary during the periovulatory period. Immature female rats (22-23 days old) were treated with pregnant mare's serum gonadotropin (PMSG) to stimulate follicular development, followed 48h later by injection with human chorionic gonadotrophin (hCG). Ovaries, granulosa cells, or theca-interstitial cells were collected at various times after hCG administration. Both real-time polymerase chain reaction (PCR) and in situ hybridisation analysis revealed that Riok3 was highly induced in both granulosa cells and theca-interstitial cells by hCG. Riok3 expression was induced in theca-interstitial cells at 4h after hCG. However, the expression of Riok3 mRNA was stimulated in granulosa cells at 8h. Both protein kinase C inhibitor (GF109203) and the protein kinase A inhibitor (H89) could block the stimulation of Riok3 mRNA by hCG. Furthermore, Riok3 induction is dependent on new protein synthesis. Inhibition of prostaglandin synthesis or progesterone action did not alter Riok3 mRNA expression, whereas inhibition of the epidermal growth factor (EGF) pathway downregulated Riok3 expression. In conclusion, our findings suggest that the induction of the RIOK3 may be important for ovulation and luteinisation.

The Biological Function Prediction of The 10-gingerol Compound of Ginger in Inhibiting Cyclooxygenase-2 Activity

Anti-inflammatory agents inhibit prostaglandin synthesis by blocking cyclooxygenases (COXs). The compounds extracted from ginger, 10-gingerol and 10-shogaol can inhibit inflammation but the mechanism of inhibition remains unclear. Here we used molecular docking to predict the molecular interactions between COXs and the three inhibitors, acetaminophen (CID1983), 10-gingerol (CID168115) and 10-shogaol (CID6442612). By using that acetaminophen as a gold standard, the results demonstrated that acetaminophen, 10-gingerol, and 10-shogaol could bind catalytic domain and membrane binding domain of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). The 10-shogaol did not show significantly different binding energy to bind to COX-1 and COX-2. The 10-gingerol posed a stronger and more specific binding to the membrane-binding domain of COX-2 than acetaminophen and 10-shogaol. The specific binding of the 10-gingerol to COX-2 could prevent the binding of the natural substrate, arachidonic acid. The results provide useful information to improving activities of anti-inflammatory.

Improved Femtosecond Laser-Assisted Phacoemulsification of Hard Nucleus Cataract

Purpose: The development and clinical study of improved femtosecond laser-assisted phacoemulsification (PE) technology of hard nucleus cataract.Patients and methods. Improved femtosecond laser-assisted PE of hard nucleus cataract performed in 83 patients (93 eyes) (1st group), known femtosecond laser-assisted PE technique performed in 72 patients (78 eyes) (2nd group), torsional PE performed in 81 patients (89 eyes) (3rd group). The degree of intraoperative myosis, effective ultrasound time, corneal endothelial cell loss were evaluated in all groups.Results. Femtosecond laser-assisted PE is an effective technique for hard nucleus cataract removal, which can significantly reduce the energy ultrasonic load on the eye tissue. The proposed method for the instillation of prostaglandin synthesis inhibitors and the observance of the minimum possible interval between the first and second stages of the operation can prevent significant intraoperative narrowing of the pupil. A significant narrowing of the pupil by more than 2 mm after the femtolaser stage was noted in 7 (7.5 %) cases in the 1st group of patients, in 15 (16.9 %) cases in the 2nd group, in 5 (6.4 %) cases in the 3rd group. The results of the study has shown a significant decrease in the effective ultrasound time for a femtosecond laser-assisted PE compared with a torsional PE. The effective ultrasound time was in the 1st group (improved technology of femtosecond laser-assisted PE) — 3.81 ± 0.75, in the 2nd group (known technology of the femtosecond laser-assisted PE) — 5.23 ± 1.07 s (p < 0.05), in the 3rd group (OZil technology) — 8.67 ± 1.83 s (p < 0.05). The decrease in the effective ultrasound time has become a determining factor in reducing the loss of corneal endothelial cells in both femtosecond laser-assisted PE technologies compared to torsional PE. The average loss of corneal endothelial cells 3 months after surgery was 8.7 ± 1.8 % in the 1st group, 10.3 ± 2.1% in the 2nd group, 13.5 ± 2.7 % (p < 0.05) in the 3rd group of patients.Conclusion. The proposed improved technology contributes to the solution of some problems that characterize femtosecond laser-assisted PE, and also helps to reduce the effective ultrasound time and the loss of corneal endothelial cells.

Effect of Organic Anion Transporters on the Development of Nephrotoxicity in the Context of NSAIDs Use

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used worldwide as pain relievers, antipyretics, and anti-inflammatory drugs. Failure to comply with the instructions for medical use of this group of drugs increases the risk of serious adverse reactions on the part of different organs and systems. From 5 to 18% of patients taking NSAIDs develop adverse reactions associated with impaired renal function. Organic anion transporter (OAT) proteins, which mediate the drug excretion with urine, have an important role to play in the NSAIDs adverse effect on kidneys. The aim of the study was to analyse and systematize scientific literature on the role of OATs in nephrotoxicity development in the context of NSAIDs use. It was revealed that adverse kidney reactions associated with NSAIDs are determined by several mechanisms, including inhibition of prostaglandin synthesis due to cyclooxeganse-1 and/or cyclooxeganse-2 blockade, and direct toxic effect on renal tubule epithelium followed by tubular necrosis due to NSAIDs interaction with OATs. Moreover, by suppressing OAT1 and OAT3, NSAIDs can not only enhance, but also reduce nephrotoxic effects of other medicines (when used together) and endogenous/exogenous toxins. Considering that NSAIDs are widely used in the treatment of various diseases (including in elderly patients and patients with concomitant renal diseases), it is still relevant to study mechanisms of adverse kidney reactions associated with drug transporters.

Anti-inflammatory studies on a saponin albichinoside

Introduction: Pain and inflammation are a day to day affliction for all living beings. Mankind has for years been trying to relieve the agony of pain & inflammation through various means with a large amount of success. Still we have not been able to produce the ideal analgesic or the ideal anti-inflammatory drug. The objective of this study was to evaluate a saponin, albichinoside, with respect to its ability to relieve pain and /or show anti-inflammatory activity. Materials and Methods: The study was conducted on rats. The saponin was evaluated for its effects on acute, sub-acute, chronic and immunological inflammation by using standard anti-inflammatory study protocols. Results: The test substance showed significant inhibition of acute, sub-acute and chronic inflammation produced by immunological and non-immunological methods in rats. These activities were qualitatively less as compared to indomethacin. This activity was like that of non-steroidal anti-inflammatory agents. Conclusion: The test substance has moderate anti-inflammatory activity which could be by means of inhibition of prostaglandin synthesis and the complement. Keywords: Saponin, Anti-inflammatory, Animals.

In-vivo analgesic activity of ethanol leaf extract of Sphenocentrum Jollyanum in albino mice

This study assessed the in-vivo analgesic activity of ethanol leaf extract of Sphenocentrum jollyanum in albino mice using analgesic models such as acetic acid-induced abdominal writhing, formalin-induced paw licking and thermally-induced pain in mice. Acetylsalicylic acid (ASA) was used as the reference drugs for the acid-induced abdominal writhing and formalin-induced paw licking while Dexamethasone was used as standard drug for thermally-induced pain. A total of seventy-five matured Swiss Albino mice of both sexes weighing between 15 – 25 g (divided into three groups of 25 mice each for the 3 different studies) were used for this study. They were randomly divided into 5 groups of five mice each. Group I served as the normal control and received 10 mL/kg body weight (bw) distilled water. Group II (Standard control), received standard drugs- Acetylsalicylic acid (ASA) or Dexamethasone. Groups III, IV and V received 474.34, 948.68 and 1423.03 mg/kg bw ethanol leaf extract of S. jollyanum respectively. All administration was done intraperitoneally. The animals were fed normal rat pellet and had water ad libitum. The results showed a significant (p< 0.05) dose dependent reduction in the acetic acid-induced abdominal writhing and formalin-induced paw licking at all doses (Groups III-V) compared with acetylsalicylic acid standard drug Group II. In the acetic acid-induced writhing and formalin paw licking models, the extract had the highest writhing and paw licking effects of 37.40± 0.68 and 28.60 ± 0.60 at the highest dose of 1423.03 mg/kg respectively. Similarly, the extract caused a dose-dependent increase in percentage inhibition of abdominal writhing and paw licking effects at total timing of 105 mins with the highest dose of 1423.03 mg/kg respectively. Additionally, the extract (groups III-V) and standard drug (II) demonstrated a dose-dependent (p < 0.05) increase in PRT compared with control group I, with the standard drug dexamethasone (group II) having the highest effect. Sphenocentrum Jollyanum leaves extract also showed significant increase in PRT from 135 to 190% compared to control group I. The result obtained from this study suggests that the extract of Sphenocentrum Jollyanum leaf may be an effective analgesic agent that may act by the inhibition of prostaglandin synthesis or via peripheral mechanism of pain inhibition.

Can NSAIDs Be Used Safely for Analgesia in Patients with CKD?: PRO

Nearly 60% of patients with CKD suffer pain. Of those patients with CKD who have pain, most rate their pain as moderate or severe in intensity. Undermanaged pain is associated with higher rates of mood disorders, maladaptive coping, and decreased quality of life for patients with CKD (1). In general, nonsteroidal anti-inflammatory drugs (NSAIDs) are recommended as first-line for analgesia and also act as antipyretics and anti-inflammatory medications. Estimates indicate that 98 million patients annually are prescribed NSAIDs (2), which likely represents only a fraction of total use given widespread nonprescription access. Epidemiologic studies suggest that 70%–80% of all NSAID users consume over-the-counter products like ibuprofen or naproxen (3,4). In the National Health and Nutrition Examination Survey, routine NSAID use was common in patients with CKD and use increased with increasing CKD severity (3). NSAIDs have well-known adverse effects in CKD patients. These risks can broadly be categorized into affecting the kidneys, gastrointestinal (GI) tract, or cardiovascular system. Among these risks, it is the direct and indirect nephrotoxicity that has primarily led to hesitation with the use of NSAIDs in patients with CKD. In one study, patients with CKD were more likely to receive an opioid than an NSAID or gabapentinoid across the entire spectrum of CKD (5). The highest rates of opioid prescribing were in patients with the lowest GFR. Indirect nephrotoxicity from NSAIDs is linked to altered intraglomerular hemodynamics. NSAIDs inhibit PG synthesis, which decreases afferent arteriolar vasodilation and can reduce glomerular pressure. This is especially prominent in patients with already jeopardized renal perfusion as in shock or intravascular volume depletion. For this reason, use of NSAIDs in acutely ill patients with AKI, acute kidney disease, or in the midst of renal recovery remains ill-advised. Patterns of direct nephrotoxicity include interstitial nephritis, papillary necrosis, and …

Clinical and biological features of haptoglobin phenotypes

Haptoglobin is a late positive acute phase protein of inflammation. Haptoglobin binds to free hemoglobin released from erythrocytes during intravascular hemolysis to form a complex which is removed shortly. Other properties like inhibition of oxidative stress and prostaglandin synthesis have been described. Three main phenotypes of haptoglobin have been identified: Hp1-1, Hp2-1, Hp2-2, which may have an impact in different diseases such as cardiovascular or infectious diseases. Haptoglobins of different phenotypes can be separated by capillary electrophoresis. They may induce a split of the alpha 2-globulin zone in the electrophoretic pattern. Hp1-1 and Hp2-1 phenotypes induce an important and a moderate split of the α2 globulin zone, respectively, whereas Hp2-2 does not. In vitro hemolysis and migration of a monoclonal component (i.e. immunoglobulin free light chain) may also induce a split of the alpha 2-globulin zone. In daily practice, Hp2-1 or Hp1-1 phenotypes could be notified in the electrophoresis report to alert the clinician about the possible physiopathological consequences.

PGE2 upregulates gene expression of dual oxidase in a lepidopteran insect midgut via cAMP signalling pathway.

In insect midgut, prostaglandins (PGs) play a crucial role in defending bacterial and malarial pathogens. However, little is known about the PG signalling pathway in the midgut. A dual oxidase (Se-Duox) with presumed function of catalysing reactive oxygen species (ROS) production in the midgut was identified in beet armyworm, Spodoptera exigua. Se-Duox was expressed in all developmental stages, exhibiting relatively high expression levels in the midgut of late larval instars. Se-Duox expression was upregulated upon bacterial challenge. RNA interference (RNAi) of Se-Duox expression significantly suppressed ROS levels in the midgut lumen. The suppression of ROS levels increased insecticidal activity of Serratia marcescens after oral infection. Interestingly, treatment with a PLA2 inhibitor prevented the induction of Se-Duox expression in response to bacterial challenge. On the other hand, addition of its catalytic product rescued the induction of Se-Duox expression. Especially, PG synthesis inhibitor significantly suppressed Se-Duox expression, while the addition of PGE2 or PGD2 rescued the inhibition. Subsequent PG signals involved cAMP and downstream components because specific inhibitors of cAMP signal components such as adenylate cyclase (AC) and protein kinase A (PKA) significantly inhibited Se-Duox expression. Indeed, addition of a cAMP analogue stimulated Se-Duox expression in the midgut. Furthermore, individual RNAi specific to PGE2 receptor (a trimeric G-protein subunit), AC, PKA or cAMP-responsive element-binding protein resulted in suppression of Se-Duox expression. These results suggest that PGs can activate midgut immunity via cAMP signalling pathway by inducing Se-Duox expression along with increased ROS levels.

Regular use of ibuprofen reduces rat penile prostaglandins and induces cavernosal fibrosis

Ibuprofen is a commonly used non-steroidal anti-inflammatory drug that is noted for its favorable safety profile. It exerts its therapeutic effect through inhibition of prostaglandin (PG) production at inflammatory sites. However, the inhibition of PG synthesis at other sites is responsible for the occurrence of adverse events. Evidence regarding the effect of regular ibuprofen intake on penile PG homeostasis or penile histopathologic changes is lacking. The aim of this study was to examine the effect of regular administration of analgesic therapeutic doses of ibuprofen on penile PG E1 and F2α and penile microscopic changes of the treated rats. This study included four groups of adult male Wistar rats; a control group (I) injected intraperitoneally with saline (2 ml/kg/day) for 30 days and 3 ibuprofen-treated groups (IIa, IIb, and IIc) injected intraperitoneally with 6 mg/kg/day, 12 mg/kg/day, and 18 mg/kg/day ibuprofen, respectively, for 30 days, respectively. Mean levels of penile PGE1 and PGF2α in the control group were significantly higher than ibuprofen-treated groups IIa, IIb, and IIc. The percentage area of collagen around cavernous tissue was significantly higher in ibuprofen-treated groups IIa, IIb, and IIc than control rats. Our findings suggest that despite ibuprofen’s safety profile, regular use of ibuprofen is associated with reduced penile PG and increased cavernosal fibrosis.

A New Insight into Meloxicam: Assessment of Antioxidant and Anti-Glycating Activity in In Vitro Studies.

Meloxicam is a non-steroidal anti-inflammatory drug, which has a preferential inhibitory effect to cyclooxyganase-2 (COX-2). Although the drug inhibits prostaglandin synthesis, the exact mechanism of meloxicam is still unknown. This is the first study to assess the effect of meloxicam on protein glyco-oxidation as well as antioxidant activity. For this purpose, we used an in vitro model of oxidized bovine serum albumin (BSA). Glucose, fructose, ribose, glyoxal and methylglyoxal were used as glycating agents, while chloramine T was used as an oxidant. We evaluated the antioxidant properties of albumin (2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity, total antioxidant capacity and ferric reducing antioxidant power), the intensity of protein glycation (Amadori products, advanced glycation end products) and glyco-oxidation (dityrosine, kynurenine, N-formylkynurenine, tryptophan and amyloid-β) as well as the content of protein oxidation products (advanced oxidation protein products, carbonyl groups and thiol groups). We have demonstrated that meloxicam enhances the antioxidant properties of albumin and prevents the protein oxidation and glycation under the influence of various factors such as sugars, aldehydes and oxidants. Importantly, the antioxidant and anti-glycating activity is similar to that of routinely used antioxidants such as captopril, Trolox, reduced glutathione and lipoic acid as well as protein glycation inhibitors (aminoguanidine). Pleiotropic action of meloxicam may increase the effectiveness of anti-inflammatory treatment in diseases with oxidative stress etiology.

Abstract 912: Synergistic combination of oncolytic virotherapy and immunotherapy for glioma

Abstract Oncolytic viral immunotherapy is a novel approach to cancer treatment. Viruses can directly kill cancer cells, provide antigens to dendritic cells to stimulate a T cell response, and make cancer cells express genes of immune-enhancing cytokines locally within the tumor microenvironment. We hypothesized that the combination of oncolytic virus with a local stimulus for activating tumor-specific T cells and an anti-immunosuppressant would improve treatment of gliomas and applying the combination treatment after the resection of late-stage established glioma might overcome immunosuppression caused by surgical trauma, kill the residual tumor and cure glioma-bearing mice. Virally encoded IL15Rα-IL15 as the T cell activating stimulus and a prostaglandin synthesis inhibitor as the anti-immunosuppressant were combined with adoptive transfer of tumor-specific T cells. Two oncolytic poxviruses, vvDD vaccinia virus and myxoma virus, were each engineered to express the fusion protein IL15Rα-IL15 and a fluorescent protein. Viral gene expression (YFP or tdTomato Red) was confirmed in the murine glioma GL261 in vitro and in vivo. GL261 tumors in immunocompetent C57BL/6J mice were treated with vvDD-IL15Rα-YFP vaccinia virus or vMyx-IL15Rα-tdTr combined with other treatments, including vaccination with GARC-1 peptide (a neoantigen for GL261), rapamycin, celecoxib, and adoptive T cell therapy. The feasibility of partial resection of late-stage established glioma in mouse brain was confirmed. We found that vvDD-IL15Rα-YFP and vMyx-IL15Rα-tdTr each infected and killed GL261 cells in vitro. In vivo, NK cells and CD8+ T cells were increased in the tumor due to the expression of IL15Rα-IL15. Each component of a combination treatment contributed to prolonging survival: an oncolytic virus, the IL15Rα-IL15 expressed by the virus, a source of T cells (whether by pre-vaccination or adoptive transfer), and prostaglandin inhibition all synergized to produce elimination of gliomas in a majority of mice. vvDD-IL15Rα-YFP occasionally caused encephalitis, but vMyx-IL15Rα-tdTr was safe and effective, causing a strong infiltration of tumor-specific T cells and eliminating gliomas in 83% of treated mice All these facts suggest that IL15Rα-IL15-armed oncolytic poxviruses provide potent antitumor effects against brain tumors when combined with adoptive T cell therapy, rapamycin and celecoxib. And it is possible to do tumor resection on mice bearing late-stage glioma. We are working on applying the combination treatment after the resection of late-stage established glioma. Citation Format: Bingtao Tang, Zong Sheng Guo, David Bartlett, Jia Liu, Grant McFadden, Joanna Shisler, Kari Foss, Heidi Phillips, Terence Lichtor, Edward Roy. Synergistic combination of oncolytic virotherapy and immunotherapy for glioma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 912.

The Novel Aspirin as Breakthrough Drug for COVID-19: A Narrative Review

Introduction: Aspirin has justifiably been called the first miracle drug. In this article, we highlight the history of Aspirin, a novel mechanism of action, and its use in cardiovascular and other diseases. Also included is a brief statement of emerging new applications. Objective: We highlight principal mechanisms by which Aspirin inhibits acute inflammation and alters platelet-biology; therefore, hypothesized that Aspirin might prove highly beneficial as a novel therapeutic drug for combating severe acute inflammation and thrombosis associated with the cytokine storm in COVID -19 patients. The communiqué also suggests possible strategies for maximizing the gain of Aspirin as a wonder-drug of the future. Discussion: Interestingly, some fascinating studies demonstrated Aspirin's superior benefits with dangerous side effects. Aspirin inhibits COX-1 (cyclooxygenase-1). Its impact on COX-2 is more delicate because it “turns off” COX-2's production of prostaglandins but “switches on” the enzymatic ability to produce novel protective lipid mediators. The established mechanism of action of Aspirin is the inhibition of prostaglandin synthesis. However, further evidence showed that aspirin-elicited nitric oxide exerts anti-inflammatory effects in the microcirculation by inhibiting leukocyte– endothelium interactions. Interestingly, aspirin-triggered lipoxin formation may provide a novel mechanism underlying Aspirin's clinical benefits. Interestingly, Aspirin reduces the risk of a cardiovascular event by about 30 percent. Also, Aspirin has been associated with a reduced risk of colorectal cancer, and possibly a few other digestive tract cancers. Conclusion: The current emerging interest is to conduct further study to provide evidence for Aspirin as the novel therapeutic drug for combating severe acute inflammation and thrombosis associated with the cytokine storm in COVID-19 patients. Besides, the most wanted is The RECOVERY II (Randomized Evaluation of COVID-19 Therapy II) trial to be established as a randomized clinical trial to test the effectiveness of low-dose Aspirin as an anti-inflammatory and antithrombotic treatment in COVID-19 patients.

Enhanced Myogenic Constriction in the SHR Preglomerular Vessels Is Mediated by Thromboxane A2 Synthesis.

BackgroundSpontaneously Hypertensive Rats (SHR) have chronically elevated blood pressures at 30 weeks of age (systolic: 191.0 ± 1.0, diastolic: 128.8 ± 0.9). However, despite this chronic malignant hypertension, SHR kidneys remain relatively free of pathology due to having an augmented myogenic constriction (MC). We hypothesized that the enhanced MC in the SHR preglomerular vessels was due to increased prostaglandin and decreased nitric oxide (NO) synthesis, providing renal protection.MethodsSHR and Wistar Kyoto (WKY) arcuate and mesenteric arteries were treated with indomethacin (prostaglandin synthesis inhibitor), N omega-nitro-L-arginine (L-NNA, NO synthase inhibitor), and nifedipine (L-type calcium channel blocker); and MC was measured in these vessels. The role of endothelium in MC was examined by removing endothelium from WKY and SHR preglomerular and mesenteric arteries using human hair, and measuring MC. We also studied the source of prostaglandin in the SHR by treating endothelium-removed arcuate arteries with indomethacin and furegrelate (thromboxane synthase inhibitor).ResultsMC was enhanced in the SHR preglomerular vessels but not the mesenteric arteries. Indomethacin and LNNA removed the enhanced MC in the SHR. Nifedipine also inhibited MC in both WKY and SHR arcuate and mesenteric arteries. Removing endothelium did not change MC in either arcuate or mesenteric arteries of WKY and SHR rats; and did not remove the augmented MC in the SHR arcuate arteries. Indomethacin and furegrelate decreased MC in endothelium-removed SHR arcuate arteries and obliterated the enhanced MC in the SHR.ConclusionThe enhanced MC in the SHR arcuate arteries was due to thromboxane A2 synthesis from the tunica media and/or adventitia layers. MC was not dependent on endothelium, but was dependent on L-type calcium channels. Nevertheless, SHR arcuate arteries displayed differential intracellular calcium signaling compared to the WKYs.

Phosphodiesterase-5 inhibitors ameliorate structural kidney damage in a rat model of contrast-induced nephropathy

The aim of the study was to investigate the potential of sildenafil and tadalafil to ameliorate structural kidney damage in contrast-induced nephropathy (CIN). A rat model of CIN was developed by dehydration, administration of a nitric oxide inhibitor and a prostaglandin synthesis inhibitor (L-NAME/indomethacin) and contrast media exposure to iopromide. The effect of pre-treatment with sildenafil, tadalafil or N-acetyl cysteine (NAC) for 7 days prior to CIN induction was investigated. All animals were sacrificed at 24 h after CIN induction and both kidneys were collected. Histopathological examination was performed under light microscopy in serial tissue sections stained with hematoxylin and eosin. CIN group showed hydropic changes of the renal tubules (proximal and distal convoluted tubules and Henle's loop), an increased Bowman space with lobulated glomerulus and alteration of macula densa region of distal convolute tubules. The groups pretreated with sildenafil and tadalafil showed nearly normal histological aspects of renal tissue. The group pretreated with NAC showed similar but less intense histopathologic changes compared to CIN group. Sildenafil and tadalafil pre-treatment ameliorates CIN-related structural kidney damage and the protective potential of these agents is superior to NAC.

Synergistic Combination of Oncolytic Virotherapy and Immunotherapy for Glioma.

We hypothesized that the combination of a local stimulus for activating tumor-specific T cells and an anti-immunosuppressant would improve treatment of gliomas. Virally encoded IL15Rα-IL15 as the T-cell activating stimulus and a prostaglandin synthesis inhibitor as the anti-immunosuppressant were combined with adoptive transfer of tumor-specific T cells. Two oncolytic poxviruses, vvDD vaccinia virus and myxoma virus, were each engineered to express the fusion protein IL15Rα-IL15 and a fluorescent protein. Viral gene expression (YFP or tdTomato Red) was confirmed in the murine glioma GL261 in vitro and in vivo. GL261 tumors in immunocompetent C57BL/6J mice were treated with vvDD-IL15Rα-YFP vaccinia virus or vMyx-IL15Rα-tdTr combined with other treatments, including vaccination with GARC-1 peptide (a neoantigen for GL261), rapamycin, celecoxib, and adoptive T-cell therapy. vvDD-IL15Rα-YFP and vMyx-IL15Rα-tdTr each infected and killed GL261 cells in vitro. In vivo, NK cells and CD8+ T cells were increased in the tumor due to the expression of IL15Rα-IL15. Each component of a combination treatment contributed to prolonging survival: an oncolytic virus, the IL15Rα-IL15 expressed by the virus, a source of T cells (whether by prevaccination or adoptive transfer), and prostaglandin inhibition all synergized to produce elimination of gliomas in a majority of mice. vvDD-IL15Rα-YFP occasionally caused ventriculitis-meningitis, but vMyx-IL15Rα-tdTr was safe and effective, causing a strong infiltration of tumor-specific T cells and eliminating gliomas in 83% of treated mice. IL15Rα-IL15-armed oncolytic poxviruses provide potent antitumor effects against brain tumors when combined with adoptive T-cell therapy, rapamycin, and celecoxib.

Chronic Alcohol Drinking Increases L‐Type Voltage‐Gated Calcium Channel Cav1.2 in the Substantia Nigra

Studies report that 77 % of methamphetamine (Meth)‐dependent adults in the United States also have alcohol use disorder. This comorbidity is associated with negative cognitive and behavioral effects. In addition, the serial exposure of alcohol and then methamphetamine (Meth) to adult male Sprague Dawley rats is neurotoxic and marked by a loss of tyrosine hydroxylase‐positive dopamine (DA) cells in the substantia nigra pars compacta (SNpc) that is absent after either drug alone. Dopamine cell loss was associated with caspase‐3 mediated apoptosis after Meth exposure to alcohol drinking rats; however, the effect of alcohol that sensitizes DA cells to Meth‐induced apoptosis remains unknown. Adult male Sprague Dawley rats had access to either two bottles of water or a choice of 10% alcohol and water every other day over 28 days. Rats with access to alcohol every other day had significantly increased L‐type voltage gated calcium channel Cav1.2 protein in the substantia nigra (SN) (33 ± 1.4 %) at 1 day after the last day of alcohol drinking compared to water drinking only controls (p&lt;0.05). The increases in Cav1.2 were region‐specific since no such changes were detected in tissue from other dopaminergic regions including the dorsal striatum, ventral tegmental area, and nucleus accumbens. Furthermore, the cyclooxygenase‐2 selective and prostaglandin synthesis inhibitor, nimesulide (7.5mg/kg i.p., b.i.d.) administered on days when alcohol was not available, blocked the increases in Cav1.2 at 1 day after the alcohol drinking paradigm. Nimesulide administered only during the alcohol drinking paradigm also blocked the loss of DA cells in the SN pars compacta measured 1 week after exposure of Meth (10 mg/kg q 2 hrs X 4 injections). Although previous studies by others showed chronic alcohol exposure increases Cav1.2 in other brain regions, this is the first evidence of increases in the SN and that the increases occur in a prostaglandin synthesis‐dependent manner. The results are consistent with the excitotoxic effects produced calcium dysregulation and suggest that prostaglandins and disruption of calcium homeostasis produced by voluntary alcohol drinking sensitize DA cells in the SN to the neurodegenerative effects produced by the serial exposure to alcohol and Meth.Support or Funding InformationThis work is supported by the National Institutes of Health [DA042737].

Interaction between hyperbaric oxygen therapy and prostaglandin synthesis inhibition in the formalin pain test

BackgroundPain is the main symptom of inflammatory diseases, such as diabetes mellitus, hypertension, osteoarthritis among others. Lipopolysacaccharide from E. coli (LPS) has been used to induce an inflammatory process. Prostaglandins has a role in inflammation so that NSAIDs are useful pharmacological tools to treat it. Hyperbaric oxygen therapy (HBOT) has also been used in some of these diseases. However, information about pharmacological interaction with HBOT and its mechanism is scarce. So, the purpose of this work was to study the interaction between LPS, HBOT and NSAIDs using a formalin pain test.Methods96 adults male Wistar rats (150 to 200 g) were used and 2 groups treated with LPS or its vehicle were formed and each of them was divided in the next subgroups (n=8 each): Control, indomethacin, rofecoxib, HBOT, HBOT/indomethacin and HBOT/rofecoxib. 20 μL of 2% formalin was injected into the plantar surface of the right hind paw. Then nociceptive behavior was evaluated as the number of flinches in 1 min every 5 for 60 min. LPS and HBOT were applied 4 and 2.5 h prior to formalin respectively. Additionally, PGE2 and PGI2 was quantified using RP‐HPLC‐UV.ResultsFormalin produces a nociceptive behavior that decreased in the first 10 min (phase I) and in the next 50 increased to a plateau and then become to reduce (phase II, inflammatory). LPS increased and HBOT and drugs treatment reduced the phase II, while PGI2 levels were increased with LPS and reduced with HBOT and drugs. The HBOT seems to increase the indomethacin antinociceptive effect but HBOT effect was lesser than control and levels of prostaglandins were similar than in absence of HBOT. LPS treatment reduced the rofecoxib and HBOT effect increasing PGE2 and PGI2 levels respectively. Finally, when HBOT is associated with LPS and indomethacin, an increase on AUC of formalin and PGI2 levels was observed.ConclusionsThe HBOT and prostaglandin synthesis inhibition were effective antinociceptive interventions. However, indomethacin but not rofecoxib increased the HBOT antinoceptive effect diminishing PGI2 levels. In presence of an inflammatory process, the effect of HBOT and rofecoxib but no indomethacin, the antinociception was lost due to an increase in prostaglandin synthesis. Therefore, there are an interaction between HBOT and PG synthesis inhibition and the presence of inflammation reduced the beneficial effects of physical or pharmacological interventions.Support or Funding InformationThe authors would like to acknowledge CONACYT (557096) for their financial support

Dnmt3a loss and Idh2 neomorphic mutations mutually potentiate malignant hematopoiesis

AbstractMutations in the epigenetic regulators DNMT3A and IDH1/2 co-occur in patients with acute myeloid leukemia and lymphoma. In this study, these 2 epigenetic mutations cooperated to induce leukemia. Leukemia-initiating cells from Dnmt3a−/− mice that express an IDH2 neomorphic mutant have a megakaryocyte-erythroid progenitor–like immunophenotype, activate a stem-cell–like gene signature, and repress differentiated progenitor genes. We observed an epigenomic dysregulation with the gain of repressive H3K9 trimethylation and loss of H3K9 acetylation in diseased mouse bone marrow hematopoietic stem and progenitor cells (HSPCs). HDAC inhibitors rapidly reversed the H3K9 methylation/acetylation imbalance in diseased mouse HSPCs while reducing the leukemia burden. In addition, using targeted metabolomic profiling for the first time in mouse leukemia models, we also showed that prostaglandin E2 is overproduced in double-mutant HSPCs, rendering them sensitive to prostaglandin synthesis inhibition. These data revealed that Dnmt3a and Idh2 mutations are synergistic events in leukemogenesis and that HSPCs carrying both mutations are sensitive to induced differentiation by the inhibition of both prostaglandin synthesis and HDAC, which may reveal new therapeutic opportunities for patients carrying IDH1/2 mutations.