Gamma-Ray Treatment of Echinococcus Protoscoleces prior to Implantation in Mice Reduces Echinococcosis

In Vivo Therapeutic Effect of Some Medicinal Plants' Methanolic Extracts on the Growth and Development of Secondary Hydatid Cyst Infection

PURPOSE

The current study aimed to explore the in vivo therapeutic effects of the methanolic extracts of Citrullus colocynthis, Ruta graveolens, and Peganum harmala against hydatid cyst secondary infection.

METHODS

Aerial parts of P. harmala and R. graveolens, including leaves and stems, and seeds of C. colocynthis were collected and extracted using absolute methanol. Rats that are infected with secondary infection of hydatid cysts were treated orally and intraperitoneally according to the determined lethal doses for 30 days. Histological, hematological, and biochemical investigations were done 8 months after the infection.

RESULTS

Compared to Albendazole drug, C. colocynthis, and P. harmala, the methanol extract of R. graveolens showed higher and significant (P < 0.05) therapeutic effects on the secondary hydatid cysts growth. Those effects were represented by the reduction in the cysts' number, size, and weight; as well as the significant changes (P < 0.05) in values of hematological and biochemical parameters, the elevation of IFN-γ levels, and the decline of IL-10 and IL-4 cytokines, compared to the negative control group in both routes of treatment (oral and IP). Moreover, the histological sections showed that R. graveolens has a clear damaging effect on the hydatid cysts GL in the infected rats represented by the detachment of GL from LL and AL.

CONCLUSION

This study can open an avenue to find new therapeutics for secondary hydatid cyst infections using the studied plant extracts, especially the extract of R. graveolens.

In vitro Scolicidal Efficacy of 5-Fluorouracil and Radiation Against Protoscoleces of Echinococcus granulosus Sensu Lato

PURPOSE

Cystic echinococcosis (CE) caused by Echinococcus granulosus sensu lato (s.l.) is a globally distributed zoonosis. CE treatment is difficult, but radiation and 5-fluorouracil (5-FU) can be effective. However, the combination of radiation and 5-FU has not been reported. This study evaluated the effect of combination of 5-FU and radiation on E. granulosus s.l. protoscoleces (PSCs).

MATERIAL AND METHODS

In this study, PSCs were collected from the liver of diseased sheep, and some were exposed to a single dose of 20 Gy 6-MV X-ray combined with (5 μg/mL or 10 μg/mL) 5-FU in vitro. Methylene blue staining was used to detect the viability of the PSCs. Transcription of EgHSP70 and Egp38 was measured by quantitative real-time PCR (qRT- PCR).

RESULTS

A single dose of radiation killed 18% of the PSCs, and 5-FU showed weak parasiticidal efficacy on the first day of treatment. After 14 d, 5 μg and 10 μg/mL of 5-FU killed 40.20% and 50.02% of the PSCs, whereas 20 Gy of radiation killed 31.44%. The combination of 5-FU (10 μg/mL) with 20 Gy of radiation showed 77.55% killing efficacy. qRT-PCR showed that 5-FU inhibited Egp38 expression, whereas radiation increased its expression. EgHSP70 was highly expressed 14 days after radiation treatment. The data indicate that 5-FU has parasiticidal efficacy against the PSCs of E. granulosus s.l.

CONCLUSION

The lethal efficacy of PSCs caused by a single dose of radiation exposure is related to the upregulated expression level of Egp38 and EgHSP70. The killing effect of 5-FU (10 μg/mL) with 20Gy of radiation was significantly better than that of single treatment group. This study provided a basis for the potential role of 5-FU combined with radiation in the treatment of CE.

Effect of intensity-modulated radiation therapy on sciatic nerve injury caused by echinococcosis

Conventional radiotherapy has a good killing effect on femoral echinococcosis. However, the sciatic nerve around the lesion is irreversibly damaged owing to bystander effects. Although intensity-modulated radiation therapy shows great advantages for precise dose distribution into lesions, it is unknown whether intensity-modulated radiation therapy can perfectly protect the surrounding sciatic nerve on the basis of good killing of femoral echinococcosis foci. Therefore, this study comparatively analyzed differences between intensity-modulated radiation therapy and conventional radiotherapy on the basis of safety to peripheral nerves. Pure-breed Meriones meridiani with bilateral femoral echinococcosis were selected as the research object. Intensity-modulated radiation therapy was used to treat left femoral echinococcosis of Meriones meridianus, while conventional radiotherapy was used to treat right femoral echinococcosis of the same Meriones meridianus. The total radiation dose was 40 Gy. To understand whether intensity-modulated radiation therapy and conventional radiotherapy can kill femoral echinococcosis, trypan blue staining was used to detect pathological changes of bone Echinococcus granulosus and protoscolex death after radiotherapy. Additionally, enzyme histochemical staining was utilized to measure acid phosphatase activity in the protoscolex after radiotherapy. One week after radiotherapy, the overall structure of echinococcosis in bilateral femurs of Meriones meridiani treated by intensity-modulated radiation therapy disappeared. There was no significant difference in the mortality rate of protoscoleces of Echinococcus granulosus between the bilateral femurs of Meriones meridiani. Moreover, there was no significant difference in acid phosphatase activity in the protoscolex of Echinococcus granulosus between bilateral femurs. To understand the injury of sciatic nerve surrounding the foci of femoral echinococcosis caused by intensity-modulated radiation therapy and conventional radiotherapy, the ultrastructure of sciatic nerves after radiotherapy was observed by transmission electron microscopy. Additionally, apoptosis of neurons was examined using a terminal-deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, and expression of Bcl-2 and Bax in sciatic nerve tissue was detected by immunohistochemical staining and western blot assay. Our results showed that most neurons in the left sciatic nerve of Meriones meridiani with echinococcosis treated by intensity-modulated radiation therapy had reversible injury, and there was no obvious apoptosis. Compared with conventional radiotherapy, the number of apoptotic cells and Bax expression in sciatic nerve treated by intensity-modulated radiation therapy were significantly decreased, while Bcl-2 expression was significantly increased. Our findings suggest that intensity-modulated radiation therapy has the same therapeutic effect on echinococcosis as conventional radiotherapy, and can reduce apoptosis of the sciatic nerve around foci caused by radiotherapy. Experiments were approved by the Animal Ethics Committee of People’s Hospital of Xinjiang Uygur Autonomous Region, China (Approval No. 20130301A41) on March 1, 2013.

Experimentally Induced Cerebral Cystic Echinococcosis in Rats: A Suitable Animal Model for Cerebral Echinococcosis

BACKGROUND

Echinococcus granulosus is a worldwide zoonotic cestode that lives mainly in the intestine of dog as definitive host. Its larval stage infects intermediate hosts and forms hydatid cysts mainly in the liver and lungs tissues and less other organs such as brain, eye and bone. In the experimental models, inoculation of protoscoleces into the peritoneum, thoracic cavity, subcutaneous and cerebrum produces hydatid cysts. Experimental echinococcosis in the animal models provides a good opportunity for study of the parasite-host relationship, different transmission ways of infection in the intermediate hosts and effect of new drugs.

METHODS

The present study was conducted in the Veterinary School, Shahid Bahonar University of Kerman, Kerman, Iran in 2018. In this study, cerebral hydatidosis was investigated in 6 female Wistar rats weighing (200±20 gr). For this purpose, protoscoleces were collected from hydatid cysts of infected sheep liver. Overall, 300 protoscolices were injected directly in the lateral ventricle by an insulin syringe through the implanted cannula.

RESULTS

After 4 months of inoculation, multiple thin-walled, transparent hydatid cysts were observed in the rat skull. All cysts were infertile. The cysts were localized prominently on the cerebral cortex and lesser in the parenchyma and ventricles. The cyst walls consisted of three layers consist of the outer layer (fibrous capsule), two parasitic layers and the endocyst layer (germinal layer). The cyst was surrounded by the inflammatory cells consist of lymphocytes, plasma cells and macrophages.

CONCLUSION

To the best of our knowledge, this research is the first experimental cerebral hydatidosis arisen from larval stage of Echinococcus granulosus in the animal model.

The Investigation of the Effect and Mechanism of Sophora moorcroftiana Alkaloids in Combination with Albendazole on Echinococcosis in an Experimental Rats Model

Echinococcosis is a worldwide anthropozoonosis which is highly endemic over large animal husbandry areas in northwestern China. The current clinical therapeutic medicine against echinococcosis is albendazole, although it caused serious side effects in patients. The component in traditional Chinese herb medicine, Sophora moorcroftiana alkaloids (SA), is thought to be a potential drug to treat echinococcosis. In order to explore the effect and mechanism of SA treatment against echinococcosis, we established animal echinococcosis model and treated rats with albendazole alone, alkaloids alone, and combined therapy. The combined treatment showed effective inhibition against parasite infection due to induction of host response and alleviated liver injury; meanwhile albendazole caused serious liver problem. The proteomics study revealed that the combined therapy might induce complement activation through C3, C4, C5, SERPINA1, and SERPINC1 proteins and cell adhesion by ANXA2, EZR, YWHAB, HSP90AN1, and PRKAR2A proteins, while albendazole treatment could induce liver injury through CRYAB, YWHAZ, SLC25A24, and HSPA1B proteins that were involved in cell death. In all, we consider that the combinational treatment displayed better therapeutic effects against liver echinococcosis as well as alleviated liver injury, which could be considered as an effective strategy to treat echinococcosis clinically.