Vinpocetine alleviates intestinal ischemia/reperfusion injury and enhances M2 macrophage polarization in rats: Role of SIRT1/SOCS3/STAT3 signaling pathway

Vinpocetine (Vinpo) is a neuroprotective vasodilator drug. It is an effective therapeutic agent for a variety of cerebrovascular and cognitive disorders. However, its potential protective efficacy on intestinal ischemia/reperfusion (I/R) injury remains elusive. The present study aimed to investigate the effect of Vinpo on intestinal I/R injury and to explore its modulatory effect on sirtuin (SIRT1)/ Suppressor of cytokine signaling (SOCS3)/ Signal Transducer and Activator of Transcription (STAT3) signaling. Twenty-four male Wistar albino rats were randomly allocated into four groups. G1 (sham): rats were subjected to surgical stress without I/R, GII (I/R): rats were subjected to 60 min/2-h I/R, GIII (Vinpo + I/R): rats were pre-treated with Vinpo (20 mg/kg/day, P.O. daily) for 2 weeks before intestinal I/R; GIV (EX527 + Vinpo + I/R): rats received both Vinpo (20 mg/kg/day, P.O.) and EX527 (5 mg/kg, once every 2 days, i.p) for 2 weeks before intestinal I/R. The current results showed that Vinpo improved the intestinal histopathological picture, enhanced M1 to M2 macrophage polarization and alleviated the I/R-induced increase in interleukins (IL-6, IL-1β), tumor necrosis factor (TNF-α), inducible nitric oxide synthase (i-NOS), and nitric oxide (NO). Additionally, Vinpo pretreatment upregulated SIRT1 mRNA expression/protein level and SOCS3 mRNA expression while downregulating P-STAT3 immunoreactivity. The effects of Vinpo were attenuated by the SIRT1 inhibitor EX527. We concluded that Vinpo ameliorated the intestinal I/R injury and enhanced M2 anti-inflammatory macrophage polarization through modulation of SIRT1/SOCS3/STAT3/i-NOS cascade.

Rebamipide protects against experimentally induced intestinal ischemia/reperfusion-promoted liver damage: Impact on SIRT1/β-catenin/FOXO1and NFκB signaling

Rebamipide (Reba) is a well-known gastroprotective agent. However, its potential protective efficacy against intestinal ischemia/reperfusion (I/R)-induced liver injury remains elusive. Therefore, this study aimed to assess the modulatory effect of Reba on SIRT1/β-catenin/FOXO1-NFκB signaling cascade. Thirty-two male Wistar albino rats were randomized into four groups: G1 (sham): rats were subjected to surgical stress without I/R, GII (I/R): rats were subjected to 60 min/4-h I/R, GIII (Reba + I/R): rats received Reba 100 mg/kg/day, p.o. for three weeks, then were subjected to 60 min/4-h I/R, and GIV (Reba + EX527 + I/R): rats received Reba (100 mg/kg/day p.o.) + EX527 (10 mg/kg/day, ip) for three weeks before I/R. Reba pretreatment decreased the serum levels of ALT and AST, improved I/R-induced histological alterations of both intestine and liver, increased hepatic Silent information regulator 1 (SIRT1) expression/content, β-catenin expression/immunoreactivity, and FOXO1 expression, while suppressed NF-κB p65 expression/protein content. In addition, Reba increased hepatic total antioxidant capacity (TAC), while suppressed malondialdehyde (MDA), tumor necrosis factor (TNFα), and caspase-3 activity. Furthermore, Reba inhibited BAX expression, while upregulated Bcl-2 expression. Reba exhibited a plausible protective effect against intestinal I/R-mediated liver injury by modulating SIRT1/β-catenin/FOXO1-NFκB signaling mechanisms.

Comparative protective effects of N-acetylcysteine and melatonin against obesity-induced testicular dysfunction in rats

N-acetylcysteine (NAC) and melatonin were reported to exert protective effects on testicular tissues. Thus, this study aimed to determine which of these is more efficient against obesity-induced testicular dysfunction in albino rats. A total of 32 adult male rats (195 ± 10 g) were divided into four groups: control, obese rats fed a high-fat diet (HFD), HFD+NAC (150 mg/kg per day, i.p.) and HFD+melatonin (10 mg/kg per day, i.p.), for 5 weeks. Testes and epididymis were weighed. Lipid profile, pituitary-testicular hormones, tumor necrosis factor α (TNFα), epididymal sperm parameters, testicular oxidant-antioxidant system, testicular and the epididymal histopathology and immunohistochemical localization for androgen receptors (AR) and Bax reaction were analyzed. Administration of NAC or melatonin significantly improved the lipid parameters, gonadal hormones, TNFα level, sperm count and abnormal morphology, oxidant-antioxidant system and the absolute testicular and epididymal mass with an enhancement of testicular architecture, AR expression and apoptosis as compared with that in the obese group. Additionally, as compared with the NAC group, the melatonin group had significantly reduced body mass index, total cholesterol, triglyceride, and TNFα and increased testosterone, sperm count, motility, superoxide dismutase activity, mitigated histomorphometrical changes, Bax expression, and increased testicular AR expression. Therefore, melatonin was more efficient than NAC in affording fortification against HFD-induced testicular dysfunction.

Oxygen free radical and nitric oxide production in single or combined human schistosomiasis and fascioliasis

The levels of superoxide (O(-)2) and nitric oxide (NO) production by monocytes have been measured in 15 patients with S. mansoni, 15 patients with Fasciola and six patients with combined infection as well as in control group (15). The levels of both radicals were significantly higher in all patient groups than in the control group, indicating that these radicals may have a role in the immunity against such infections. Patients with chronic fascioliasis showed lower level of O(-)2 and NO than those with schistosomiasis. This may be due to the lodging of the mature Fasciola spp. away from the immune system and subsequently decreased amount of antigens reaching the circulation. In combined infection, the levels of these products were at the highest value, due to increased antigenic stimulation and cross reactivity between the two parasites which may have lead to augmented immune response.

Production of pro-inflammatory cytokines (GM-CSF, IL-8 and IL-6) by monocytes from fasciolosis patients

The production of pro-inflammatory cytokines by monocytes in vitro has been measured in eight patients with acute fasciolosis and 15 patients in the chronic stage of the disease, before and after stimulation by excretory/secretory Fasciola antigen. Results were compared with those of a control group of 12 individuals. The monocytes from patients with acute fasciolosis produced significantly higher levels of GM-CSF, IL-8 and IL-6 as compared to controls. With chronicity, the production of these cytokines was decreased as compared to the acute stage probably due to decreased antigen level in blood. Stimulation of monocytes of healthy control with E/S Fasciola antigen was accompanied with a markedly increased production of pro-inflammatory cytokines, while monocytes from patients with acute or chronic fasciolosis revealed minimal increase in production. This denoted the importance of E/S Fasciola antigen as an activator of monocytes. A second exposure to the same antigen was accompanied with a limited response.

Laboratory assessment of the molluscicidal activity of Commiphora molmol (Myrrh) on Biomphalaria alexandrina, Bulinus truncatus and Lymnaea cailliaudi

The molluscicidal properties of the oil extract of Commiphora molmol (Myrrh) were tested against Egyptian snail species: Biomphalaria alexandrina, Bulinus truncatus and Limnaea cailliaudi. The impact of the extract on the egg cluches of B. alexandrina and L. cailliaudi was also evaluated. Snails and their eggs were exposed for 24 and 48 hr at 22-26 degrees C to various concentrations of the extract. The results showed different susceptibilities B. alexandrina showed higher LD50 and LD90 (155, 195 ppm) than B. truncatus (50, 95 ppm) and L. cailliaudi (50, 85 ppm) after 24 hr exposure. 100% mortality was obtained for the egg cluches of B. alexandrina and L. cailliaudi at concentrations of 100 ppm and 75 ppm respectively. Lower concentrations were needed to obtain the same results after 48 hr. The present laboratory studies demonstrated that Myrrh has a molluscicidal effect on the snail intermediate hosts, particularly on their eggs. Field studies are recommended.

On the schistosomicidal effect of triclabendazole an experimental study

Mice were infected with S. mansoni cercariae and divided to three groups: one as control, the others were treated with a single oral dose of PZQ or TCBZ. The efficacy of the drugs was evaluated on the basis of egg excretion, number, sex and distribution of worms, oogram changes and tissue egg load. Results demonstrated that eggs disappeared from the stools in both treated groups, all worms died in the PZQ treated group while in the TCBZ group, worm production amounted to 84%. Male worms were more susceptible to the two drugs, they died earlier. On the fourth week after TCBZ, the few surviving worms returned back from their hepatic shift to the mesenteric veins. By studying the oogram pattern, it was found that PZQ had a direct lethal effect on the mature eggs; TCBZ had a lower effect on egg viability but the oogram findings indicated cessation of egg laying.

Tumour necrosis factor-alpha (TNF-alpha) in human toxoplasmosis

Tumour necrosis factor alpha (TNF-alpha) is a cytokine that is secreted by activated macrophages and monocytes. This work studied TNF-alpha level in sera of patients with toxoplasmosis. Twenty eight female patients (12 of whom had obstetric troubles) and 17 healthy controls were the subjects in this work. According to IHA test and detection of IgM antibodies, three groups of patients were defined, group (I) patients with acute infection, group (II) patients with chronic infection and had high antibody titre, group (III) patients with chronic infections and had low antibody titre. Sera from patients as well as controls were tested for their level of immunologically reactive TNF-alpha using enzyme-linked immunosorbant assay (ELISA). TNF-alpha levels in the sera of patients were significantly higher as compared to healthy control group. Acute infection was associated with the highest levels of TNF-alpha indicating that it may play a role in the pathogenesis of acute toxoplasmosis. In chronic infection, the level of TNF-alpha correlated with IHA antibody titre suggesting that, antibodies against T. gondii may participate in TNF-alpha production. It could be concluded that TNF-alpha may contribute to the pathology in acute infection and may play a role in modulating the host's immune defence against T. gondii in chronic infections.

Studies on human fascioliasis in Egypt. 1--Seasonality of transmission

The present study aimed at investigating the seasonality of human fascioliasis. The monthly distribution of acute infection was studied together with the monthly Lymnaea cailliaudi snail density and infection Infection was observed in both snail and human host through out the year. However maximal snail infection was observed during the months of June and July while the number of acute human infections peaked in August. It was concluded that summer was the highest transmission season. The clinical incubation period was considered one or two months.