Albendazole - Ivermectin combination decreases inflammation in experimental neurocysticercosis

Repositioning anthelmintics for the treatment of inflammatory-based pathological conditions

Acute, uncontrolled and/or long-lasting inflammation causes a breakdown in immunological tolerance, leading to chronicity and contributing to a series of significant local or systemic tissue changes. Anti-inflammatory efficacy, fewer adverse effects, improved selectivity, and curative action are imminent issues for patients suffering from chronic inflammation-related pathologies. Then, we performed a complete and critical review about anthelmintics, discussing the main classes and the available preclinical evidence on repurposing to treat inflammation-based conditions. Despite low bioavailability, many benzimidazoles (albendazole and mebendazole), salicylanilides (niclosamide), macrocyclic lactones (avermectins), pyrazinoisoquinolones (praziquantel), thiazolides (nitazoxanide), piperazine derivatives, and imidazothiazoles (levamisole) indicate that repositioning is a promising strategy. They may represent a lower cost and time-saving course to expand anti-inflammatory options. Although mechanisms of action are not fully elucidated and well-delineated, in general, anthelmintics disrupt mitogen-activated protein kinases, the synthesis of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8, IL-12, and IFN-γ), the migration and infiltration of leukocytes, and decrease COX-2 expression, which impacts negatively on the release of prostanoids and leukotrienes. Moreover, some of them reduce nuclear accumulation of NF-κB (niclosamide, albendazole, and ivermectin), levels of nitric oxide (nitazoxanide and albendazole), and mucus, cytokines, and bronchoconstriction in experimental inflammatory pulmonary diseases (ivermectin and niclosamide). Considering the linking between cytokines, bradykinin, histamine, and nociceptors with algesia, anthelmintics also stand out for treating inflammatory pain disorders (ivermectin, niclosamide, nitazoxanide, mebendazole, levamisole), including for cancer-related pain status. There are obstacles, including the low bioavailability and the first-pass metabolism.

Murine Extraparenchymal Neurocysticercosis: Appropriate Model for Evaluating Anthelminthic and Anti-Inflammatory Treatment Schedules

BACKGROUND

Experimental models of neurocysticercosis (NCC) are helpful for an improved understanding of the pathophysiological mechanisms of human diseases and for testing novel therapeutic approaches. Controlling inflammation without reducing the effectiveness of anthelmintics is an important challenge in treating neurocysticercosis. This study investigates the effects of currently used drugs (Albendazole and Dexamethasone) in treating murine extraparenchymal NCC.

METHODS

Twenty-two rats were inoculated with Taenia crassiceps in the subarachnoid space. The animals underwent magnetic resonance imaging to ascertain the success of infection 3 months after inoculation. The infected animals were randomly assigned to one of the three groups (five rats each): control (no treatment), Albendazole (ABZ), or Albendazole + Dexamethasone (ABZ + DXM) for 14 days. The animals were subsequently euthanised for morphological assessment 2 weeks after the end of treatment.

RESULTS

Macroscopically integrated cysts were found in all animals. The ABZ + DXM animals demonstrated lower ventricular sizes, lymphocyte infiltration rates, and immunopositivity for IL-6, with statistical differences in lymphocytes within the arachnoid region.

CONCLUSIONS

This experimental model, which has previously shown similarities to human infections, is also helpful in reproducing the morphological changes upon treatment with Albendazole and Dexamethasone.

Ubenimex combined with Albendazole for the treatment of Echinococcus multilocularis-induced alveolar echinococcosis in mice

Introduction

Alveolar echinococcosis (AE) is a parasitic disease caused by E. multilocularis metacestodes and it is highly prevalent in the northern hemisphere. We have previously found that vaccination with E. multilocularis-Leucine aminopeptidase (EM-LAP) could inhibit the growth and invasion of E. multilocularis in host liver, and Ubenimex, a broad-spectrum inhibitor of LAP, could also inhibit E. multilocularis invasion but had a limited effect on the growth and development of E. multilocularis.

Methods

In this study, the therapeutic effect of Ubenimex combined with Albendazole on AE was evaluated. Mice were intraperitoneally injected with protoscoleces and imaging examination was performed at week 8 and week 16 to detect cyst change. During this period, mice were intraperitoneally injected with Ubenimex and intragastrically administered with Albendazole suspension. At last, the therapeutic effect was evaluated by morphological and pathological examination and liver function.

Results

The results revealed that the combined treatment could inhibit the growth and infiltration of cysts in BALB/c mice infected with E. multilocularis protoscoleces. The weight, number, invasion and fibrosis of cysts were reduced in mice treated with Ubenimex in combination with Albendazole. The same effect was achieved by the single Ubenimex treatment because of its inhibitory effect on LAP activity, but it was less effective in inhibiting the growth of cysts. The levels of ALT, AST, TBIL, DBIL, ALP, and γ-GT were reduced after the combined treatment, indicating that treatment with both Ubenimex and Albendazole could alleviate liver damage.

Discussion

This study suggests that the combined treatment with Ubenimex and Albendazole could be a potential therapeutic strategy for E. multilocularis infections.