Evaluation of colchicine with or without praziquantel therapy in the control of hepatic fibrosis in murine schistosomiasis

Doxycycline aggravates granulomatous inflammation and lung microstructural remodeling induced by Schistosoma mansoni infection

Although doxycycline exhibits immunomodulatory properties, its effects on pulmonary infection by Schistosoma mansoni remain overlooked. Thus, we investigated the impact of this drug on lung granulomatous inflammation and microstructural remodeling in a murine model of schistosomiasis. Swiss mice were randomized in four groups: (i) uninfected, (ii) infected with S. mansoni and untreated, (iii) infected treated with praziquantel (Pzq; 200 mg/kg), and (iv) infected treated with Dox (50 mg/kg). Pz was administered in a single dose, and Dox for 60 days. S. mansoni induced marked granulomatous lung inflammation, which was associated to cytokines upregulation (IL-2, IL-4, IL-10, IFN-γ, TNF-α, and TGF-β), neutrophils and macrophages recruitment, alveolar collapse, lung fibrosis, and extensive depletion of elastic fibers. These parameters were attenuated by Pzq and aggravated by Dox. Exudative/productive granulomas were predominant in untreated and Dox-treated animals, while fibrotic granulomas were more frequent in Pzq-treated mice. The number and size of granulomas in Dox-treated animals was higher than untreated and Pzq-treated mice. Dox treatment inhibited the increase in MMP-1 and MMP-2 activity but upregulated myeloperoxidase and N-acetylglucosaminidase activity compared to untreated and Pzq-treated animals. Dox and Pzq exerted no effect on elastin depletion and upregulation of elastase activity. Together, our findings indicated that Dox aggravated granulomatous inflammation, accelerating lung microstructural remodeling by downregulating MMP-1 and MMP-2 activity without impair neutrophils and macrophages recruitment or elastase activity. Thus, Dox potentiates inflammatory damage associated with lung fibrosis, elastin depletion and massive alveolar collapse, profoundly subverting lung structure in S. mansoni-infected mice.

Is there a correlation between HPV and urinary bladder carcinoma?

AIMS

To detect human papilloma virus (HPV) infection, p21 oncogene, DNA content of urothelial cells in different bladder lesions with and without schistosomiasis and to correlate them with histopathological grade and stage.

METHODS

Eighty-five patients were enrolled: 25 chronic cystitis and 60 malignant bladder lesions; 15 schistosomal squamous cell carcinoma (SQCC), 45 urothelial carcinoma (transitional cell carcinoma TCC) schistosomal and non-scistosomal. Ten healthy individuals served as controls. Genotyping of HPV 6/11 and 16/18 were done using in situ hybridization and p21 protein expression by Immunohistochemical technique in formalin-fixed, paraffin-embedded tissues. DNA content of urothelial cells were stained with felugen stains and measured using Automated Image analysis System.

RESULTS

HPV DNA 6/11 and 16/18 expression was increased from cases of schistosomal cystitis with dysplasia to TCC with schistosomiasis compared to TCC and SQCC. The expression increased with statistical significance in invasive TCC and high-grade compared with superficial and low grade. Over-expression of p21 in invasive TCC group was compared with superficial TCC, high-grade TCC was compared low grade and TCC was compared with SQCC. Almost all cases of TCC associated with schistosomiasis exhibit aneuploid histogram compared to SQCC and all invasive TCC exhibited aneuploid histograms.

CONCLUSIONS

Both HPV infection and p21 gene abnormalities may contribute to bilharzial bladder carcinogenesis. DNA image cytometric features may predict stage progression in TCC. Expression of p21, DNA HPV 6/11 and 16/18 may be used as biological markers of bladder carcinoma.

Impact of treatment with praziquantel, silymarin and/or β-glucan on pathophysiological markers of liver damage and fibrosis in mice infected with Mesocestoides vogae (Cestoda) tetrathyridia

Mesocestoides vogae tetrathyridia infection in mice causes hepatocyte injury, hepatic granulomatous inflammmation, liver fibrosis and chronic peritonitis manifested with portal hypertension. To reduce the detrimental effect of parasites on the host liver, the effect of the anthelmintic drug praziquantel (PZQ) in combination with natural products silymarin (an antioxidant) and β-glucan (an immunomodulator) was investigated. The therapeutic effect of drugs was assessed by means of aminotransferase (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) activities, content of albumin, total proteins and hyaluronic acid (HA) in sera of ICR mice infected with M. vogae larvae. Animals were treated with PZQ suspended in oil emulsion (Group 1), PZQ combined with silymarin incorporated into lipid microspheres (LMS) (Group 2), PZQ combined with β-glucan incorporated into liposomes (LG) (Group 3), PZQ co-administered with LMS and LG (Group 4). Untreated animals (Group 5) served as the control. Treatment of animals started at the early chronic phase of infection (day 14 p.i.) and lasted 10 days; serum samples were collected on days 0, 7, 14, 25, 28, 31, 35 and 45 p.i. ALT and AST activities were significantly (P < 0.05) decreased in Groups 2, 3 and 4. HA content was significantly (P < 0.05 and 0.01) lower in Groups 2 and 4. Albumin levels were decreased in Groups 2 and 4, total protein concentration decreased in Groups 1 and 3 (P < 0.05 and 0.01). These results showed that combined treatment of PZQ with silymarin and/or β-glucan was able to ameliorate or suppress fibrogenesis in the liver, protect liver cells from oxidative damage and, possibly, stimulate regeneration of the parenchyma.

RNA interference targeting Fas protects mice from fulminant hepatitis

RNA interference (RNAi) is a powerful tool to silence gene expression post-transcriptionally. However, its potential to treat or prevent disease remains unproven. Fas-mediated apoptosis is implicated in a broad spectrum of liver diseases, where inhibiting hepatocyte death is life-saving. We investigated the in vivo silencing effect of small interfering RNA (siRNA) duplexes targeting the gene Fas (also known as Tnfrsf6), encoding the Fas receptor, to protect mice from liver failure and fibrosis in two models of autoimmune hepatitis. Intravenous injection of Fas siRNA specifically reduced Fas mRNA levels and expression of Fas protein in mouse hepatocytes, and the effects persisted without diminution for 10 days. Hepatocytes isolated from mice treated with Fas siRNA were resistant to apoptosis when exposed to Fas-specific antibody or co-cultured with concanavalin A (ConA)-stimulated hepatic mononuclear cells. Treatment with Fas siRNA 2 days before ConA challenge abrogated hepatocyte necrosis and inflammatory infiltration and markedly reduced serum concentrations of transaminases. Administering Fas siRNA beginning one week after initiating weekly ConA injections protected mice from liver fibrosis. In a more fulminant hepatitis induced by injecting agonistic Fas-specific antibody, 82% of mice treated with siRNA that effectively silenced Fas survived for 10 days of observation, whereas all control mice died within 3 days. Silencing Fas expression with RNAi holds therapeutic promise to prevent liver injury by protecting hepatocytes from cytotoxicity.

Colchicine therapy for hepatic murine schistosomal fibrosis: image analysis and serological study

Colchicine in a dose of 200 micrograms kg body weight/day (5 days/week) was administered to groups of Schistosoma mansoni infected mice 12 weeks post infection, either alone or following previous praziquantel therapy at the 8th week of infection. Certain groups received colchicine for 6 weeks and others received it for 10 weeks. Colchicine alone did not significantly change the light microscopic appearance of schistosomal liver fibrosis, or hepatic collagen content estimated histomorphometrically, and did not reduce the elevated IL-2 serum level. Colchicine induced hepatic injury consisted of intense inflammatory reaction in granuloma and portal tracts, hepatocytic degeneration, and elevation of serum AST and ALT levels. Colchicine seemed to postpone granulomatous reaction healing and collagen deposition rather than inhibiting collagen formation or degrading it. Colchicine inhibited proliferation of hepatocytes of infected mice by expanding G2-M phases of cell cycle, thus reduced Ag NOR count and raised cell ploidy and cyclic AMP serum level. Subsidence of schistosomal infection by praziquantel prior to colchicine therapy greatly reduced inflammatory cellular reaction, significantly diminished hepatic collagen deposition and serum IL-2 level, minimized the elevated nuclear ploidy and cyclic AMP serum level that followed colchicine therapy when administered alone.