Mahmoud Abdel-Latif

Immune stimulation improves endocrine and neural fetal outcomes in a model of maternofetal thyrotoxicosis

The potentiation of the immune system in pregnant rats was performed with Complete Freunds Adjuvant [CFA; 20μl, subcutaneous at gestation day (GD) 18] in experimentally-induced hyperthyroidism by Levo-thyroxine (L-T4; 10μg/100g of b.w., intraperitoneal from GD 2 to 17). The potential effects on the fetal neuroendocrine function were evaluated by observing some histopathological investigations in pregnant rats and measuring some biochemical parameters in dams and their fetuses at GD 20. In hyperthyroid group, an increase in maternofetal serum thyroxine (T4), triiodothyronine (T3) and a decrease in thyrotropin (TSH) levels were noticed, while the concentrations of fetal serum growth hormone (GH) and insulin-like growth factor-1 (IGF1) levels were increased at tested GD with respect to control and CFA groups. Moreover, the activity of uterine and placental myeloperoxidase (MPO) was increased (P<0.001) in CFA and CFA-treated hyperthyroid groups in respect to control or hyperthyroid groups, respectively. The gestational thyrotoxicosis led to some histopathological lesions in uterine and placental tissues characterized by severe degeneration in trophoblast spongioblast cell layer with congestion, mild congested blood vessels in the endometrium and deficient in spiral artery remodeling. Although, the elevation in fetal serum transforming growth factor-beta (TGFβ) and cerebellar monoamines [norepineprine (NE), epinephrine (E), dopamine (DA) and 5-hydroxytryptamine (5-HT)] was observed, the reduction in fetal serum tumor necrosis factor-alpha (TNFα) and adipokines (Leptin and adiponectin) was detected. Treatment of dams with CFA showed an obviously reversing and protecting effect against hyperthyroid perturbations. Thus, the maternal CFA can be used in treatment of the fetal neuroendocrine dysfunctions.

Setaria equina: in vivo effect of diethylcarbamazine citrate on microfilariae in albino rats.

Although diethylcarbamazine citrate (DEC) is successful drug in eliminating human filariasis, yet, its mode of action is still debatable. Herein, the effect of DEC to treat albino rats infected with the animal filarial parasite Setaria equina was tested. Microfilarial (mf) counts and sections from liver, lung, kidney as well as spleen were investigated at different time points after treatment by light microscopy. After 45 and 300min of treatment, a significant decrease in blood mf was observed accompanied by adherence of degenerated mf to both kupffer cells and leukocyte in liver sections. In lung sections, loss of sheath was observed at 45min, while degeneration was observed at later time points. In kidney sections, more mf counts and less matrix were observed in the glomeruli at all time points after treatment. Degenerated mf were observed in spleen sections only at, late time point, 480min after treatment. In conclusion, one of the possible mechanisms by which DEC reduces blood microfilarial count is trapping larvae in organs and killing them through cellular adherence.

Pyrazole-hydrazone derivatives as anti-inflammatory agents: Design, synthesis, biological evaluation, COX-1,2/5-LOX inhibition and docking study

A new series of pyrazole-hydrazone derivatives 4a-i were designed and synthesized, their chemical structures were confirmed by IR, 1H NMR, 13C NMR, MS spectral data and elemental analysis. IC50 values for all prepared compounds to inhibit COX-1, COX-2 and 5-LOX enzymes were determined in vitro. Compounds 4a (IC50=0.67μM) and 4b (IC50=0.58μM) showed better COX-2 inhibitory activity than celecoxib (IC50=0.87μM) with selectivity index (SI=8.41, 10.55 in sequent) relative to celecoxib (SI=8.85). Also, compound 4a and 4b exhibited superior inhibitory activity against 5-LOX (IC50=1.92, 2.31μM) higher than zileuton (IC50=2.43μM). All target pyrazoles were screened for their ability to reduce nitric oxide production in LPS stimulated peritoneal macrophages. Compounds 4a, 4b, 4f and 4i displayed concentration dependent reduction and were screened for in vivo anti-inflammatory activity using carrageenan-induced rat paw edema assay. Compound 4f showed the highest anti-inflammatory activity (% edema inhibition=15-20%) at all doses when compared to reference drug celecoxib (% edema inhibition=15.7-17.5%). Docking studies were carried out to investigate the interaction of target compounds with COX-2 enzyme active site.

Anticoccidial activities of Chitosan on Eimeria papillata-infected mice

Eimeria spp. multiply within the intestinal tract causing severe inflammatory responses. Chitosan (CS), meanwhile, has been shown to exhibit anti-inflammatory activities in different experimental models. Here, we investigated the effect of CS on the outcome of inflammation caused by Eimeria papillata in the mouse intestine. Investigations were undertaken into the oocyst output in feces and developmental stages and goblet cells in intestinal tissue. Assays for lipid peroxidation, nitric oxide (NO), and myeloperoxidase (MPO) were also performed. T cells in intestinal tissue were counted using immunohistochemistry while total IgA in serum or intestinal wash was assayed using ELISA. In addition, mRNA expression of tumor necrosis factor alpha (TNF-α), transforming growth factor β (TGF-β), interleukin (IL)-10, and IL-4 were detected using real-time PCR. The data indicated a reduction in both oocyst output and in the number of parasite developmental stages following CS treatment, while the goblet cell hypoplasia in infected mice was also inhibited. CS decreased lipid peroxidation, NO, and MPO but did not alter the T cell count or IgA levels in comparison to the infected group. The expression of TNF-α and TGF-β decreased but IL-10 and IL-4 increased after CS treatment in comparison to the non-treated infected group. In conclusion, CS showed anti-inflammatory and protective effects against E. papillata infection.

Design, synthesis and biological screening of some novel celecoxib and etoricoxib analogs with promising COX-2 selectivity, anti-inflammatory activity and gastric safety profile

Two new series of 4,6-diaryl-3-cyanopyridine 4a-r and 1,3,5-triaryl-2-pyrazolines 6a-f and were prepared. The new compounds were evaluated for their in vitro COX-2 selectivity and in vivo anti-inflammatory activity. Compounds 4o,r and 6d,f had moderate to high selectivity index (S.I.) compared to celecoxib (selectivity indexes of 4.5, 3.14, 4.79 and 3.21, respectively) and also, showed in vivo anti-inflammatory activity approximately equal to or higher than celecoxib (edema inhibition %=60.5, 64.5, 59.3 and 59.3, after 3h, respectively) and the effective anti-inflammatory doses were (ED50=10.1, 7.8, 8.46 and 10.7mg/kg respectively, celecoxib ED50=10.8mg/kg) and ulcerogenic liability were determined for these compounds which showed promising activity by being more potent than celecoxib with nearly negligible ulcerogenic liability compared to celecoxib (reduction in ulcerogenic liability versus celecoxib=85, 82, 74 and 67%, respectively).

Diethylcarbamazine citrate ameliorates insulin resistance in high-fat diet-induced obese mice via modulation of adipose tissue inflammation.

Diethylcarbamazine citrate (DEC) had been known as anti-inflammatory drug but its effect on obesity-induced insulin resistance as a result of released inflammatory mediators from adipose tissue (AT) was not known. White male albino mice were fed with high fat diet (HFD) for 18weeks to induce obesity. DEC at different three doses (12, 50 and 200mg/kg) was orally administered twice a week starting at week 6. Body, liver and adipose tissue weights were taken, while glucose tolerance, insulin resistance, blood triglycerides and levels of adipokines (leptin, TNF-α, IL-6 and MCP-1) were tested. The activity of cyclooxygenase (COX) in the liver tissue homogenate was also tested. In addition, NF-κBp65 localization in liver cell cytoplasmic and nuclear fractions was detected using Western blotting. The only effective anti-inflammatory dose was 50mg/kg to reduce (p<0.05) the high levels of glucose, insulin and triglycerides in serum. DEC was not anti-obesity drug because the weights of body, liver and adipose tissues were not changed. Hyperleptinemia was decreased (p<0.001) and associated with a reduction in serum levels of TNF-α, IL-6 and MCP-1 (p<0.001). In addition, the activity of COX in DEC treatment decreased significantly (p<0.01), while NF-κBp65 localization in nuclear extracts was obviously inhibited in 50mg/kg treated group. It could be concluded that DEC was the only effective dose against mouse insulin resistance but not lipid accumulation.

Immunomodulatory effect of diethylcarbamazine citrate plus filarial excretory-secretory product on rat hepatocarcinogenesis.

Diethylcarbamazine citrate (DEC) had a significance in anti-filarial chemotherapy, while excretory-secretory product (ES) is released from adult filarial females. The target of the current study was to examine the immunomodulatory effect of DEC, Setaria equina ES or a combination of them on rat hepatocellular carcinoma (HCC) induced by diethylnitrosamine (DEN). In vitro effect of combined DEC and ES or ES alone on lipopolysaccharide (LPS)-stimulated rat peripheral blood mononuclear cells (PBMCs) was tested through IFN-γ assay in culture supernatants. In addition, single or repeated doses of DEC, ES or DEC+ES have been applied in white albino rats to test the effect on HCC. Levels of IFN-γ and anti-ES IgG antibodies in rat serum were assayed using ELISA. Hemolytic complement activity (CH50) was determined in serum while the concentration of nitric oxide (NO) was assayed in liver tissue. The infiltration of NK cells as well as the expression of MHC Iproliferating cell nuclear antigen (PCNA), inducible NO synthase (iNOS), Bcl2 and p53 were determined using immunohistochemistry. There was a dose-dependent increase in IFN-γ after in vitro exposure to DEC+ES. Repeated ES doses increased NO concentration (p<0.05) and expression of iNOS but reduced CH50 (p<0.001), while repeated DEC+ES doses could increase anti-ES IgG (p<0.01), IFN-γ level (p<0.05) and NK cell infiltration. The same treatments could also reduce the expression of MHC I expression, PCNA, Bcl2 and p53. This study has shown immunomodulatory and protective effects of DEC+ES repeated doses on rat HCC.

Cross-reaction of antigen preparations from adult and larval stages of the parasite Setaria equina with sera from infected humans with Wuchereria bancrofti.

Crude antigenic preparations from Setaria equina were used in ELISA and Western blotting to examine cross-reaction with human sera from areas endemic for bancroftian filariasis. Sera from normal subjects from non-endemic areas were included as negative controls. Cross-reaction was found between S. equina antigens and antibodies in the sera of Wuchereria bancrofti-infected patients, with the highest levels observed between sera of chronic infected patients and Setaria spp. crude female worm surface antigen (CFSWA). In the absence of active transmission of Setaria spp. infection, CFWSA is useful to detect chronic W. bancrofti infection before patients become symptomatic, particularly when chronic patients are known to be amicrofilaraemic. In the presence of active S. equina infection, antigens from the adult and microfilaraemic stages showed the highest degree of cross-reaction with human sera.

Immunoprotective Effect of Chitosan Particles on Hymenolepis nana - Infected Mice

Hymenolepis nana is the most commonly known intestinal cestode infecting mainly human. This study aimed to investigate the potential effect of chitosan particles (CSP) to enhance the immune system against H. nana infection. Determination of worm burden, egg output, histopathological changes, oxidative stress markers (lipid peroxidation and reduced glutathione), goblet (GCs) and mucosal mast cells (MMCs) counts in intestinal ileum was performed. In addition, levels of intestinal mRNA expression of interleukin (IL)‐4, IL‐9, stem cell factor (SCF), type I and II interferons (IFN)‐α/ γ, tumour necrosis factor (TNF)‐α, mucin 2 (MUC2) and inducible nitric oxide synthase (iNOs) were investigated using real‐time PCR. The results indicated induced reductions in adult worm and egg counts in infected mice after CSP treatment. This was associated with improvement in tissue morphometric measurements and oxidative stress which were altered after infection. Expression levels of iNOs, IFN‐α, IFN‐γ, TNF‐α and IL‐9 were decreased by CSP. Conversely, expression levels of MUC2, IL‐4 and SCF increased compared to infected untreated group. In addition, GCs and MMCs counts were normalized by CSP. In conclusion, this study could indicate the immunoprotective effect of CSP against H. nana infection. This was characterized with Th2 anti‐inflammatory responses.

Modulation of murine intestinal immunity by Moringa oleifera extract in experimental hymenolepiasis nana

The potential therapeutic value of Moringa oleifera extract (MOE), due to its anti-inflammatory and anti-oxidant effects, has been reported previously. In this study, Hymenolepis nana antigen (HNA) in combination with MOE was used in immunization against H. nana infection. Adult worm and egg counts were taken, while histological changes in the intestine were observed. Mucosal mast (MMCs) and goblet cells (GCs) were stained with specific stains, while serum and intestinal IgA were assayed using enzyme-linked immunosorbent assay (ELISA). Reduced glutathione (GSH) and lipid peroxidation (thiobarbituric acid reactive substances, TBARS) were assayed. Real-time polymerase chain reaction (PCR) was used for detection of mRNA expression in ileum tissue. The results demonstrated an improvement in the architecture of intestinal villi, decreased inducible nitric oxide synthase (iNOs) and TBARS, and increased GSH in HNA, MOE and MOE + HNA groups. In the same groups, an increase in GCs, mucin 2 (MUC2), interleukins (IL)-4, -5 and -9, and stem cell factor (SCF) versus a decrease in both interferon-gamma (IFN-γ) and transforming growth factor (TGF-β) expression appeared. HNA and MOE + HNA increased serum and intestinal IgA, respectively. MOE decreased MMCs and achieved the highest reductions in both adult worms and eggs. In conclusion, MOE could achieve protection against H. nana infections through decreased TGF-β, IFN-γ and MMC counts versus increased GC counts, T-helper cell type 2 (Th2) cytokines and IgA level.