Liver procollagen prolyl hydroxylase in Opisthorchis viverrini infected hamsters after praziquantel administration

[The features of opisthorchiasis papillitis diagnosis]

AIM

To develop an optimal diagnostic algorithm in order to the most reliable decrease of inflammatory changes severity in large duodenal papilla in patients with chronic opisthorchiasis.

MATERIAL AND METHODS

Medical reports of 384 patients with opisthorchiasis-induced cholangitis have been analyzed. Diagnostic methods were abdominal ultrasound, endoscopic ultrasound of terminal common bile duct, CT scans, MRI of abdominal organs including magnetic resonance cholangiopancreatography and esophagogastroduodenoscopy with biopsy of the papilla, ERCP and PTHC. Comprehensive general and individual analysis of each of them has determined their advantages and disadvantages.

CONCLUSION

Examination should by comprehensive to evaluate visual appearance of large duodenal papilla, lumen dimensions, state of its walls with histological research. Imaging tests are favorable to determine the diagnosis of papillitis due to possible assessment of lumen dimensions and state of the walls. While making a choice the priority should be given to endoscopic ultrasound examination. It allows visual inspection, assessment of the lumen, the walls of papilla and provides biopsy of deep structures.

Wharton's jelly-derived mesenchymal stem cells combined with praziquantel as a potential therapy for Schistosoma mansoni-induced liver fibrosis

Liver fibrosis is one of the most serious consequences of S. mansoni infection. The aim of the present study was to investigate the potential anti-fibrotic effect of human Wharton’s jelly-derived mesenchymal stem cells (WJMSCs) combined with praziquantel (PZQ) in S. mansoni-infected mice. S. mansoni-infected mice received early (8^th week post infection) and late (16^th week post infection) treatment with WJMSCs, alone and combined with oral PZQ. At the 10^th month post infection, livers were collected for subsequent flow cytometric, histopathological, morphometric, immunohistochemical, gene expression, and gelatin zymographic studies. After transplantation, WJMSCs differentiated into functioning liver-like cells as evidenced by their ability to express human hepatocyte-specific markers. Regression of S. mansoni-induced liver fibrosis was also observed in transplanted groups, as evidenced by histopathological, morphometric, and gelatin zymographic results besides decreased expression of three essential contributors to liver fibrosis in this particular model; alpha smooth muscle actin, collagen-I, and interleukin-13. PZQ additionally enhanced the beneficial effects observed in WJMSCs-treated groups. Our results suggest that combining WJMSCs to PZQ caused better enhancement in S. mansoni-induced liver fibrosis, compared to using each alone.

The Experimental Use of Syrian Hamsters

The Syrian hamster (Mesocricetus auratus) is a widely used experimental animal model. This chapter focuses primarily on the most current research uses of the hamster. More classical uses are covered only as they pertain to these current uses. Hamsters possess unique anatomical and physiological features, which make them desirable research models. Unlike other commonly used laboratory rodents, hamsters possess a cheek pouch, which can be easily everted and examined at both the gross and microscopic level. The hamster's relative size also allows for better visualization of certain biological systems including the respiratory and reproductive systems when compared to the mouse. Further, laboratory hamsters develop a variety of inherited diseases, which display similarities to human conditions. Hamsters possessing some of these inherited traits are commercially available. They are susceptible to a variety of carcinogens and develop tumors that other research animals less commonly develop. Also they are susceptible to the induction of a variety of metabolic disorders through the use of dietary manipulations. The antagonistic nature of hamsters is used to study the effect of treatment on male aggressive and defensive behaviors. Syrian hamsters display several unique characteristics that make them desired models for carcinogenesis studies.

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.

Reversal of biliary tract abnormalities associated with Opisthorchis viverrini infection following praziquantel treatment

We recently demonstrated a number of biliary tract abnormalities associated with moderate to heavy Opisthorchis viverrini infection among 95 selected village residents in north-east Thailand, who were treated with praziquantel immediately after initial examination and re-examined by abdominal ultrasonography 10 months later. Dramatic improvement in the gall-bladder status of previously infected individuals was observed, including reduction of gall-bladder length and width and regained contractibility of the organ following fatty meal consumption. The frequency of severe enhanced portal vein radicle echoes and gall-bladder sludge and wall irregularities also decreased following treatment, but persisted in many individuals. Two masses were observed in the right hepatic lobe of one individual who was previously considered normal. The findings suggest that gall-bladder abnormalities are reversible following elimination of liver fluke infection, but malignancies, once initiated, are not likely to be affected by treatment.

Time-dependent modulation of liver lesion development in Opisthorchis-infected Syrian hamster by an antihelminthic drug, praziquantel

In the North-east of Thailand, repeated antihelminthic therapy has been introduced for control of the opisthorchiasis known to be a major risk factor for cholangiocellular carcinomas. What influence this may have on tumorigenesis, however, remains unclear. The effects of administration of praziquantel, an antihelminthic drug, at different time points subsequent to infection with Opisthorchis viverrini (OV) on 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN)-initiated lesion development in the liver of female Syrian hamsters were therefore investigated. Praziquantel (250 mg/kg body weight, i.p.) was given 4, 12 or 20 weeks after infection of DHPN-treated animals (two 1000 mg/kg i.p. injections at weeks 0 and 2) with 60 OV metacercariae (at week 4). Survivors at week 38 were killed and examined. It was found that whereas praziquantel administration at the earlier two time points was effective at reducing hepatocellular nodule development, the results for cholangiocellular lesions were less pronounced, significant reduction only being evident in hamsters treated 4 weeks after parasite infestation. The findings thus indicate that enhancement of DHPN-initiated bile duct carcinogenesis by opisthorchiasis is both rapid and to a large degree irreversible. Hepatocellular lesion development in this model, on the other hand, appears to correlate more closely with the duration of parasite-associated proliferative stimulus.

Evaluation of hepatic fibrosis after oxamniquine therapy of murine schistosomiasis

Chemical and histological indices of liver fibrosis were measured after eight, 18 and 28 weeks in mice infected with Schistosoma mansoni and treated at eight weeks with oxamniquine, in mice infected with S. mansoni and not treated and in mice not infected with S. mansoni. Total worm burdens and liver egg counts were determined in the infected mice to determine severity of infection. Treatment with oxamniquine resulted in near total eradication of S. mansoni worms after 10 weeks and in their complete killing and marked reduction of eggs in the liver at 10 and 20 weeks. Liver fibrosis 10 weeks after oxamniquine treatment was not significantly different than in the untreated, infected group but there was no progression between 10 and 20 weeks after oxamniquine treatment. Fibrosis did however increase between 10 and 20 weeks in the untreated infected group. In the murine model, oxamniquine is an effective treatment for S. mansoni and prevents progression of liver fibrosis.

Effect of praziquantel on hepatic fibrosis in experimental Schistosomiasis mansoni

The effect of specific chemotherapy on hepatic fibrosis was studied in Swiss albino mice infected with Schistosoma mansoni. The effect of treatment with praziquantel at 8, 12, and 20 weeks postinfection on fibrosis was assessed by determination of total hepatic collagen content, ratio of type III/I + III collagen, granuloma volume, and histopathological examination of liver section. Total collagen content was reduced in mice treated at the 8th week of infection compared to respective infected controls. The ratio of type III/I collagen was within normal limits. The decrease in collagen deposition was not observed when treatment was given 12 or 20 weeks postinfection. Early specific treatment of schistosomiasis may be important in the therapeutic approach to the control of morbidity in schistosomiasis.

Types of collagen in Opisthorchis viverrini infected hamster liver

Levels and types of collagen from normal and Opisthorchis viverrini infected hamster livers were compared. Normal liver contained approximately twice as much type I collagen than type III collagen. Upon infection by O. viverrini, both type I and type III collagen were elevated, but the increase in type III was proportionately larger than type I collagen. Of the 3-fold increase in total collagen content of infected livers, type I and type III collagen increased 2- and 4-fold, respectively. As a result, the ratio of type I to type III collagen changed from 2 in normal liver to 1.1 in the livers of animals infected with O. viverrini. The extent of the increase in both type I and type III collagen was found to depend on the infection times and on the number of worms present. In livers infected with 50 metacercariae of O. viverrini, both collagen types increased gradually with duration of infection and reached plateau after 4 months of infection. In livers from 3 month infections, with 15 worms or less, both types of collagen increased directly with the number of worms recovered. Levels of type I and type III collagen did not increase in infections with more than 20 worms.