Gastroprotective effect of sumatriptan against indomethacin-, stress- and ethanol-induced gastric damage in male rats: Possible modulatory role of 5-hydroxytryptamine 1B/1D receptors and pro-inflammatory cytokines.

The current study was aimed to investigate the beneficial effect of sumatriptan, a 5-hydroxytryptamine 1B/1D (5HT1B/1D ) receptor agonist, on gastric ulcer in rats via stimulating 5HT1B/1D receptors and suppressing pro-inflammatory cytokines. Rats were allocated into three models of gastric ulcer: indomethacin (30 mg/kg, PO), water immersion restraint stress (WRS) and ethanol (5 ml/kg PO). Animals were administered with sumatriptan (0.01, 0.1, 0.3 and 1 mg/kg, i.p) 30 min before gastric ulcer induction. GR-127935 (0.01 mg/kg, i.p, a selective 5HT1B/1D antagonist) was administered 30 min before sumatriptan (0.1 mg/kg) injection. Macroscopic assessments (J-score), ELISA analysis of tumour necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß) and histopathological changes were performed on the rat's stomach tissues. Gastric ulcer induction in three models caused an increase in J-score, TNF-α, IL-1ß and microscopic features. Sumatriptan (0.1 mg/kg) significantly improved gastric injury induced by indomethacin, WRS and ethanol through the reduction in the J-score, TNF-α, IL-1ß and microscopic lesions. Concurrent administration of GR-127935 (0.01 mg/kg) with sumatriptan (0.1 mg/kg) reversed the gastroprotective effect of sumatriptan in three models. Sumatriptan possessed gastroprotective effects on indomethacin-, WRS- and ethanol-induced gastric damage in rats via the possible involvement of the 5HT1B/1D receptors.

Pentylenetetrazole preconditioning attenuates severity of status epilepticus induced by lithium-pilocarpine in male rats: evaluation of opioid/NMDA receptors and nitric oxide pathway.

BACKGROUND: Non-deleterious episodes of seizure preconditioning can efficiently increase the brain's resistance to the consequent severe status epilepticus (SE). In the present investigation, we intended to elucidate further (i) the effects of preconditioning with pentylenetetrazole (PTZ) in the lithium-pilocarpine model of SE in male rats, along with (ii) the possible contribution of opioid, N-Methyl-D-aspartate (NMDA) receptors, and nitric oxide (NO) signaling transduction. METHODS: In male Wistar rats, the SE was incited by lithium administration (127 mg/kg, ip) 20 h before pilocarpine (60 mg/kg, ip). PTZ preconditioning was induced via a low-dose injection of PTZ (25 mg/kg) for 5 repeated days. To investigate the underlying signaling pathway, naltrexone (NTX; a non-specific opioid receptor antagonist), MK-801 (NMDA antagonist), L-NAME (a non-specific nitric oxide synthase (NOS) inhibitor), aminoguanidine (AG; a specific inducible NOS inhibitor), and 7-Nitroindazole (7-NI; a specific neuronal NOS inhibitor) were administered 15 min before PTZ injection. RESULTS: Preconditioning with PTZ successfully ameliorates the increased SE scores due to lithium-pilocarpine-induced SE (p < 0.05). None of the drugs given without PTZ preconditioning had an impact on SE outcomes. The observed anti-convulsant effect of PTZ preconditioning is reversed by the opioid receptor antagonists and NOS inhibitors. Conversely, the NMDA receptor antagonist enhanced the anti-convulsion activity caused by PTZ preconditioning. Quantifying nitrite level in the hippocampus showed a significant NO level decline in the PTZ-preconditioned animals. CONCLUSIONS: Therefore, PTZ preconditioning generates endogenous protection against SE, possibly through targeting opioid/NMDA receptors and NO signaling transduction in the animal model of lithium-pilocarpine-induced SE.

New therapeutics for primary hyperoxaluria type 1.

PURPOSE OF REVIEW: Primary hyperoxaluria type 1 (PH1) is a rare genetic disorder that causes hepatic overproduction of oxalate and, often, nephrocalcinosis, nephrolithiasis, chronic kidney disease, and kidney failure. The purpose of the review is to provide an update on current emerging therapies for the treatment of PH1. RECENT FINDINGS: Use of ribonucleic acid interference (RNAi) therapeutics that target the liver to block production of key enzymes along pathways that generate oxalate is a promising approach. Available evidence supports the efficacy of both Lumasiran (targeting glycolate oxidase) and Nedosiran (targeting hepatic lactate dehydrogenase (LDHa)) to reduce urinary oxalate excretion in PH1. The efficacy of alternative approaches including stiripentol (an anticonvulsant drug that also targets LDHa), lanthanum (a potential gastrointestinal oxalate binder), and Oxalobacter formigenes (a bacterium that can degrade oxalate within the gastrointestinal tract and may also increase its secretion from blood) are all also under study. Genetic editing tools including clustered regularly interspaced short palindromic repeats/Cas9 are also in preclinical study as a potential PH1 therapeutic. SUMMARY: Novel treatments can reduce the plasma oxalate concentration and urinary oxalate excretion in PH1 patients. Thus, it is possible these approaches will reduce the need for combined kidney and liver transplantation to significantly decrease the morbidity and mortality of affected patients.

Inflammatory Cells in Nephrectomy Tissue from Patients without and with a History of Urinary Stone Disease.

BACKGROUND AND OBJECTIVES: Urinary stone disease has been associated with inflammation, but the specific cell interactions that mediate events remain poorly defined. This study compared calcification and inflammatory cell patterns in kidney tissue from radical nephrectomy specimens of patients without and with a history of urinary stone disease. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Nontumor parenchyma of biobanked radical nephrectomy specimens from age- and sex-matched stone formers (n=44) and nonstone formers (n=82) were compared. Calcification was detected by Yasue staining and inflammatory cell populations by immunohistochemistry for CD68 (proinflammatory M1 macrophages), CD163 and CD206 (anti-inflammatory M2 macrophages), CD3 (T lymphocytes), and tryptase (mast cells). Calcifications and inflammatory cells were quantified in cortex and medulla using Image-Pro analysis software. RESULTS: Calcification in the medulla of stone formers was higher than in nonstone formers (P<0.001). M1 macrophages in the cortex and medulla of stone formers were greater than in nonstone formers (P<0.001), and greater in stone former medulla than stone former cortex (P=0.02). There were no differences in age, sex, body mass index, tumor characteristics (size, stage, or thrombus), vascular disease status, or eGFR between the groups. M2 macrophages, T lymphocytes, and mast cells did not differ by stone former status. There was a correlation between M1 macrophages and calcification in the medulla of stone formers (rho=0.48; P=0.001) and between M2 macrophages and calcification in the medulla of nonstone formers (rho=0.35; P=0.001). T lymphocytes were correlated with calcification in the cortex of both nonstone formers (rho=0.27; P=0.01) and stone formers (rho=0.42; P=0.004), whereas mast cells and calcification were correlated only in the cortex of stone formers (rho=0.35; P=0.02). CONCLUSIONS: Higher medullary calcification stimulated accumulation of proinflammatory rather than anti-inflammatory macrophages in stone formers.

Effect of Lenalidomide on Pentylenetetrazole-Induced Clonic Seizure Threshold in Mice: A Role for N-Methyl-D-Aspartic Acid Receptor/Nitric Oxide Pathway.

BACKGROUND AND PURPOSE: Accumulating evidence suggest that lenalidomide, a structural analog of thalidomide, has neuro-modulatory and neuroprotective properties. In the present study, we investigated effects of acute administration of lenalidomide on clonic seizure threshold in mice induced by pentylenetetrazole (PTZ) and possible role of N-methyl-D-aspartic acid receptor (NMDAR) and nitric oxide (NO) pathway. METHODS: We have utilized a clonic model of seizure in NMRI mice induced by PTZ to evaluate the potential effect of lenalidomide on seizure threshold. Different doses of lenalidomide (5, 10, 20, and 50 mg/kg, intraperitoneal [i.p.]) were administered 1 hour before PTZ. To evaluate probable role of NMDAR/NO signaling, the non-selective NO synthase inhibitor L-N G-nitroarginine methyl ester (L-NAME; 10 mg/kg, i.p.), neuronal NOS (nNOS) inhibitor 7-nitroindazole (7-NI; 30 mg/kg, i.p.), selective inducible NOS inhibitor aminoguanidine (AG; 100 mg/kg, i.p.), selective NMDAR antagonist MK-801 (0.01 mg/kg, i.p.), and selective NMDAR agonist D-serine (30 mg/kg, i.p.) were injected 15 minutes before lenalidomide. RESULTS: Lenalidomide at 10 and 20 mg/kg significantly elevated the PTZ-induced seizure thresholds. Interestingly, L-NAME (10 mg/kg, i.p), 7-NI (30 mg/kg, i.p), and AG (100 mg/kg, i.p) reversed the anticonvulsive effect of lenalidomide (10 mg/kg). Moreover, treatment with the NMDAR agonist D-serine (30 mg/kg, i.p.) did not alter the anticonvulsive properties of lenalidomide (10 mg/kg, i.p). However, the NMDAR antagonist MK-801 (0.01 mg/kg, i.p) significantly reversed the anticonvulsive effects of lenalidomide (10 mg/kg). CONCLUSIONS: Our study demonstrated a role for the NMDAR/NO pathway in the anticonvulsive effects of lenalidomide on the PTZ-induced clonic seizures in mice.

Anti-inflammatory effect of amitriptyline in a rat model of acetic acid-induced colitis: the involvement of the TLR4/NF-kB signaling pathway.

Inflammatory bowel disease (IBD) consists of ulcerative colitis and Crohn's disease, which affects gastrointestinal tract. The immune-mediated inflammation is mostly considered as the pathogenesis of IBD. It has been demonstrated that amitriptyline exerts anti-inflammatory influence; therefore, the aim of the current experiment is to evaluate the anti-inflammatory impact of amitriptyline on intestinal disorders following acetic acid-induced colitis in rats. Thirty male Wistar rats were randomly divided into five groups, including sham, control, dexamethasone (2 mg/kg), and amitriptyline (10 and 20 mg/kg). Intrarectal administration of acetic acid was applied to colitis induction in all study groups except for sham group. Animals were treated by oral administration of dexamethasone or amitriptyline. While macroscopic and microscopic lesions appeared after colitis induction treatment with dexamethasone and amitriptyline 10 and 20 mg/kg significantly improved lesions. Moreover, Toll-like receptor 4 (TLR4) and nuclear factor binding kappa light-chain (NF-ĸB expression), tumor necrosis factor-alpha (TNF-α) level, and myeloperoxidase (MPO) activity were increased after colitis induction, whereas treatment with dexamethasone (2 mg/kg) or amitriptyline (10 and 20 mg/kg) caused a noticeable decrease in the TLR4 and pNF-ĸB expression, TNF-α level, and MPO activity. In conclusion, amitriptyline plays an anti-inflammatory role through the suppression of TLR4/pNF-ĸB signaling pathway in the rat model of acute colitis.

The role of medicinal products in the treatment of inflammatory bowel diseases (IBD) through inhibition of TLR4/NF-kappaB pathway.

Inflammatory bowel disease (IBD) is a lifelong and recurrent disease of the gastrointestinal tract that afflicts many people in the world. Growing evidence has currently indicated that dysfunction of immune system, particularly toll-like receptors 4 (TLR4) signaling pathway dysfunction plays a pivotal part in the pathogenesis of IBD. TLR4 signaling is involved both in the pathogenesis and in the efficacy of treatment of IBD. There are some medicinal products and herbal medicines, which their role in the treatment of IBD through modulation of TLR4 signaling has been implicated. The purpose of this review article is to summarize those medicinal products and herbal medicines.

Sumatriptan reduces severity of status epilepticus induced by lithium-pilocarpine through nitrergic transmission and 5-HT1B/D receptors in rats: A pharmacological-based evidence.

Status epilepticus (SE) is a life-threatening neurologic disorder that can be as both cause and consequence of neuroinflammation. In addition to previous reports on anti-inflammatory property of the anti-migraine medication sumatriptan, we have recently shown its anticonvulsive effects on pentylenetetrazole-induced seizure in mice. In the present study, we investigated further (i) the effects of sumatriptan in the lithium-pilocarpine SE model in rats, and (ii) the possible involvement of nitric oxide (NO), 5-hydroxytryptamin 1B/1D (5-HT1B/1D ) receptor, and inflammatory pathways in such effects of sumatriptan. Status epilepticus was induced by lithium chloride (127 mg/kg, i.p) and pilocarpine (60 mg/kg, i.p.) in Wistar rats. While SE induction increased SE scores and mortality rate, sumatriptan (0.001-1 mg/kg, i.p.) improved it (P < 0.001). Administration of the selective 5-HT1B/1D antagonist GR-127935 (0.01 mg/kg, i.p.) reversed the anticonvulsive effects of sumatriptan (0.01 mg/kg, i.p.). Although both tumor necrosis factor-α (TNF-α) and NO levels were markedly elevated in the rats' brain tissues post-SE induction, pre-treatment with sumatriptan significantly reduced both TNF-α (P < 0.05) and NO (P < 0.001) levels. Combined GR-127935 and sumatriptan treatment inhibited these anti-inflammatory effects of sumatriptan, whereas combined non-specific NOS (L-NAME) or selective neuronal NOS (7-nitroindazole) inhibitors and sumatriptan further reduced NO levels. In conclusion, sumatriptan exerted a protective effect against the clinical manifestations and mortality rate of SE in rats which is possibly through targeting 5-HT1B/1D receptors, neuroinflammation, and nitrergic transmission.

Involvement of nitric oxide pathway in the anti-inflammatory effect of modafinil on indomethacin-, stress-, and ethanol -induced gastric mucosal injury in rat.

Gastric ulcer is a prevalent disease with various etiologies, including non-steroidal anti-inflammatory drugs (NSAIDs), stress conditions, and alcohol, resulting in an inflammatory condition in the gastric mucosa. The aim of this study was to explore the protective effects of modafinil on gastric erosions induced by indomethacin, water-immersion stress, and alcohol in rats and to evaluate the role of nitric oxide (NO) pathway. Animals were allocated to the three experimental models of gastric ulcer - indomethacin (30 mg/kg PO), water-immersion stress, and ethanol (5 ml/kg PO). Induction of gastric ulcer in all models caused an increase in J-score (macroscopic assessment), biochemical markers, including tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß), and myeloperoxidase (MPO), and microscopic destructions. Administration of modafinil (50 and 100 mg/kg i. p) significantly improved J-score in the indomethacin (P < 0.05) and stress models (P < 0.001). Moreover, the level of TNF-α IL-1ß, and MPO was deceased after modafinil administration (P < 0.001). However, modafinil did not have any effects on gastric injury induced by ethanol. In addition, co-administration of L-NAME (a non-specific NO synthase inhibitor) and aminoguanidine (an inducible NO synthase inhibitor) with modafinil significantly neutralized the gastroprotective effect of modafinil in the indomethacin and water-immersion stress groups (P < 0.05, and P < 0.01; respectively), while 7-nitroindazole (a neuronal NO synthase inhibitor) did not show such reversing effects. In conclusion, modafinil possesses gastroprotective effects on the gastric lesions induced by indomethacin and stress, which are probably mediated via the inflammation inhibition and NO pathway modulation.

Risperidone attenuates acetic acid-induced colitis in rats through inhibition of TLR4/NF-kB signaling pathway.

AIM: The purpose of the present study is to explore the anti-inflammatory potential of risperidone in acetic acid-induced rat colitis through inhibition of TLR4/NF-kB pathway. METHODS: Acute colitis induction was done by intra-rectal administration of 2 mL of 4% diluted acetic acid solution. Two h after colitis induction, dexamethasone (2 mg/kg) as standard drugorrisperidone (2, 4 and 6 mg/kg) were administered orally to wistar rats for five consecutive days. 24 h after the last treatment, animals were sacrificed by cervical dislocation. Macroscopic and microscopic damage evaluation was done. Biochemical and ELISA methods were used to assess myeloid peroxidase (MPO) enzyme activity and tumor necrosis factor-α (TNF-α) level respectively. Moreover, immunohistochemistry (IHC) was performed to detect the expression of TLR4 and pNF-kBproteins. RESULTS: Dexamethasone (2 mg/kg) or risperidone (2, 4 and 6 mg/kg) improved acetic acid-induced macroscopic (p < .001) and microscopic lesions. Additionally, risperidone (2, 4 and 6 mg/kg) inhibited the activity of MPO and TNF-α (p < .01, p < .001) in the colon tissue compared to acetic acid group. Furthermore, bothdexamethasone and risperidone (2, 4 and 6 mg/kg) significantly reduced acetic acid-induced expression of TLR4and pNF-kB proteins (p < .05, p < .01, p < .001). CONCLUSION: The anti-inflammatory effect of risperidone on acetic acid-induced colitis in rats may involve inhibition of TLR4 and NF-kB signaling pathway.

Bupropion Ameliorates Acetic Acid-Induced Colitis in Rat: the Involvement of the TLR4/NF-kB Signaling Pathway.

Inflammatory bowel disease composed of ulcerative colitis and Crohn's disease is a disorder that may involve entire gastrointestinal tract. Its pathogenesis is mainly an immune-mediated inflammation. Recently, it has been indicated that bupropion possesses anti-inflammatory properties; hence, the objective of this experiment is the investigation of the anti-inflammatory influence of bupropion on colonic lesions that emerged following the intrarectal administration of acetic acid. Thirty-six male Wistar rats were allocated randomly into six groups, including control, acetic acid, dexamethasone (2 mg/kg), and bupropion (40, 80, and 160 mg/kg). Colitis was induced by intrarectal administration of acetic acid in all study groups except control group, and animals were treated by oral administration of dexamethasone and bupropion. While macroscopic and microscopic lesions were observed after colitis induction, administration of dexamethasone and bupropion 160 mg/kg led to the remarkable improvement in lesions. In addition, the expression of TLR4 and NF-ĸB was decreased after colitis induction; however, treatment with dexamethasone (2 mg/kg) and bupropion (160 mg/kg) resulted in a significant decrease in their expression. Regarding biochemical factors, following colitis induction, TNF-α level and MPO activity were increased; nevertheless, dexamethasone (2 mg/kg) and bupropion (160 mg/kg) decreased the TNF-α and MPO activity. In conclusion, bupropion exerts anti-inflammatory influence through suppressing the TLR4 and NF-ĸB expression in the rat model of acute colitis.

Biochemical and histopathological evidence for the beneficial effects of modafinil on the rat model of inflammatory bowel disease: involvement of nitric oxide pathway.

BACKGROUND: Inflammatory bowel disease is an intestinal disorder presented by recurrent inflammation in the gastrointestinal tract. It has been reported that modafinil, also known as an awakening drug, has anti-inflammatory characteristics. The objective of this experiment is to investigate the protective effects of modafinil on colitis induced by acetic acid in rat and the involvement of nitric oxide pathway. METHODS: Colitis was induced by intra-rectal instillation of 1 ml acetic acid (4%). After one h of colitis induction (first day), intraperitoneal injection of dexamethasone (1 mg/kg), modafinil (50, 100, and 150 mg/kg), nitric oxide synthase inhibitors (NOS)-N (G)-nitro-L-arginine methyl ester (L-NAME) 10 mg/kg, 7-nitroindazole 40 mg/kg, and aminoguanidine 50 mg/kg-was performed and continued for 2 consecutive days. Ultimately, macroscopic, microscopic, and biochemical assessments were performed. RESULTS: While induction of colitis caused severe macroscopic lesions, administration of dexamethasone and modafinil (100 and 150 mg/kg) significantly improved macroscopic ulcers. Interestingly, the combination of modafinil with NOS inhibitors reversed the beneficial effects of modafinil on macroscopic destructions. In addition, the elevated level of interleukin-1beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) was decreased by modafinil. However, treatment with NOS inhibitors before modafinil neutralized the anti-inflammatory influence of modafinil. Additionally, histological disorders emerged by acetic acid in colon tissue remarkably were disappeared after treatment with modafinil. CONCLUSIONS: In conclusion, modafinil has a protective effect on injuries induced by acetic acid in the colon of rat, which is presumably via the inhibition of inflammatory cascade and mediation of NO pathway.

Beneficial effects of dapsone on ischemia/reperfusion injury following torsion/detorsion in ipsilateral and contralateral testes in rat.

Testicular torsion is a serious urologic emergency and one of the causes of infertility in males. Hence, prompt diagnosis and treatment are important to prevent testicular damages. It has been proved that dapsone (4, 40 diamino-diphenyl sulfone) has anti-oxidative and anti-inflammatory effects. Therefore, the aim of this study was to investigate the influence of dapsone on ischemia/reperfusion (I/R) injury in bilateral testes after unilateral testicular torsion/detorsion (T/D) in rats. In this experiment, eighteen male Wistar rats were allocated into three groups, including sham-operated, T/D + vehicle, and T/D + dapsone (12.5 mg/kg). Testicular torsion was induced for 1 h by rotating right (ipsilateral) testis 7200 in the clockwise direction. After 7 days of reperfusion, bilateral orchiectomy was conducted and evaluations of biochemical markers - tumor necrosis factor alpha (TNF-α) and superoxide dismutase (SOD) - and histological changes were performed. While induction of testicular T/D remarkably increased the level of TNF-α in the ipsilateral (torted) and contralateral (non-torted) testes, intraperitoneal (i.p) administration of dapsone (12.5 mg/kg) significantly lowered the TNF-α level (p < 0.001). Additionally, after induction of T/D, SOD activity was notably decreased, whereas administration of dapsone (12.5 mg/kg, i.p.) significantly raised SOD activity in the bilateral testes (p < 0.001). I/R injury also caused lesions in the microscopic pattern of the bilateral testicular tissues, while administration of dapsone (12.5 mg/kg, i.p.) led to a significant improvement in testicular damages. It was concluded that dapsone had a protective impact on I/R injury in the rat model of testicular T/D, and this effect was most likely induced by anti-inflammatory and anti-oxidative properties of dapsone.

Protective effects of sumatriptan on ischaemia/reperfusion injury following torsion/detorsion in ipsilateral and contralateral testes of rat.

This study was planned to evaluate the effects of sumatriptan, 5-HT1B/1D receptors agonist, on ischaemia/reperfusion injury in bilateral testes after unilateral testicular torsion/detorsion in rats. Male Wistar rats (n = 42) were allocated into a sham-operated group, a control group and treatment groups which were injected sumatriptan (0.1, 0.3 and 1 mg/kg), GR-127935 (0.01 mg/kg)-5-HT1B/1D receptors antagonist-and sumatriptan (0.1 mg/kg) + GR-127935 (0.01 mg/kg). Torsion was induced for 1 hr by rotating right testis 7200 in the clockwise direction, and after 7 days of detorsion, bilateral orchiectomy was conducted. While the level of TNF-α rose in testicular tissue after inducing torsion/detorsion, sumatriptan injection notably lowered TNF-α level in ipsilateral (torted) and contralateral (nontorted) testes (p < 0.001). Moreover, after inducing testicular torsion/detorsion, SOD activity was decreased, whereas administration of sumatriptan significantly increased SOD activity in bilateral testes (p < 0.001). After induction of torsion/detorsion, macroscopic and histological analyses also showed severe damages which were improved by sumatriptan injection. Interestingly, co-administration of sumatriptan with GR-127935 reversed the beneficial impacts of sumatriptan on macroscopic appearance, microscopic pattern and biochemical markers. It is concluded that sumatriptan presumably via stimulation of 5-HT1B/1D receptors decreased inflammation, oxidative stress and deteriorations induced by ischaemia/reperfusion injury following testicular torsion/detorsion.