In vitro effects of harmine against Echinococcus granulosus protoscoleces by stimulating DNA damage

Harmine derivative H-2-168 induces the death of Echinococcus granulosus by regulating mitochondrial fusion and fission

CONTEXT

H-2-168 has pharmacological effects similar to those of harmine, with less toxicity. The health of cells and organisms depends on a delicate balance between mitochondrial fusion and fission.

OBJECTIVE

This study investigated the roles of H-2-168 and mitochondrial fusion and fission in Echinococcus granulosus.

MATERIALS AND METHODS

Notably, E. granulosus were isolated from fresh sheep livers, and then treated with H-2-168 (25 μg/mL), mitochondrial division inhibitor 1 (Mdivi-1, 25 μg/mL) or the combination of H-2-168:Mdivi-1 (25 μg/mL:12.5 μg/mL). After 24 h of culture, the indices related to E. granulosus were measured. Additionally, Drp1 was knocked down to explore its effects on E. granulosus growth.

RESULTS

The EC50 values of H-2-168, Mdivi-1 and H-2-168:Mdivi-1 against E. granulosus were 44.171, 117.882 and 32.924 μg/mL, respectively. Compared with H-2-168 or Mdivi-1, the combination of H-2-168 and Mdivi-1 showed better inhibitory effects on E. granulosus viability, as well as increased levels of ROS and LDH, decreased ATP levels, inhibited mitochondrial activity and reduced mitochondrial membrane potential (p < 0.05), with the upregulation of Caspase-3, Cyt-c, Drp1, Fis1 and downregulation of Bcl-2, Mfn2 and OPA1. Additionally, Drp1 knockdown was successfully performed in E. granulosus, which significantly inhibited E. granulosus viability (p < 0.05) and further downregulated Mfn2 expression induced by H-2-168.

DISCUSSION AND CONCLUSION

Drp1 is closely associated with mitochondrial fusion and fission, and H-2-168 may promote E. granulosus death through disrupting the balance between mitochondrial fusion and fission.

Promising Anthelminthic Effects of Camphene Against Protoscoleces and Hydatid Cysts of Echinococcus granulosus

BACKGROUND

The current research aims to investigate the anthelmintic effects and cellular mechanisms induced by camphene (CP), a natural monoterpene found in certain herbs, against hydatid cysts and protoscoleces (PSCs) of Echinococcus granulosus.

METHODS

The anthelmintic properties of CP were examined using the eosin exclusion assay on PSCs. The effects of CP on the expression levels of apoptotic and DNA damage-related genes in PSCs were evaluated, along with its impact on the plasma membrane (PM) and its ability to induce the generation of reactive oxygen species (ROS). The in vivo efficacy of CP, administered at doses of 20, 40, and 80 mg/kg/day for 28 days, was assessed in mice infected with hydatid cysts by measuring the quantity, dimensions, and weight of the cysts, as well as analyzing serum levels of inflammatory cytokines.

RESULTS

Results indicated that CP significantly decreased the viability of PSCs both in vitro and ex vivo (p < 0.001) compared to the control group. A notable upregulation of apoptotic genes (caspase-3 and caspase-9) and genes associated with DNA damage was observed (p < 0.001). CP treatment also enhanced plasma membrane permeability and ROS generation (p < 0.001). Furthermore, CP resulted in a dose-dependent reduction in the number, size, and weight of hydatid cysts, as well as in the serum concentrations of TNF-α and IL-1β, with no significant changes in the serum levels of biomarkers related to liver and kidney function.

CONCLUSION

Recent research has demonstrated the promising in vitro and ex vivo effects of CP on hydatid cyst PSCs. Additionally, the study highlighted the in vivo potential of CP in controlling hydatid cysts within a murine model, attributing this efficacy to its anti-inflammatory properties. However, further research is necessary to elucidate the specific mechanisms of action and to evaluate its effectiveness in clinical trials, which may facilitate the application of these nanoparticles in the treatment and management of cystic echinococcosis.

In vitro, in vivo, and cellular mechanisms of Astragalus onobrychis L. extract against protoscoleces and hydatid cysts of Echinococcus granulosus

Introduction

In this study, we evaluated the in vitro, ex vivo, and in vivo effects of the chloroform extract of Astragalus onobrychis L. (Fabaceae family) (AOCE) on apoptosis induction and DNA damage in protoscoleces and hydatid cysts of Echinococcus granulosus.

Methods

The protoscolicidal properties of AOCE were examined through both in vitro and ex vivo studies on hydatid cyst protoscoleces, utilizing the eosin exclusion assay. Additionally, we evaluated the effects of AOCE on apoptosis induction and DNA damage in the protoscoleces using a colorimetric protease assay and real-time PCR analysis, respectively. The in vivo efficacy was determined by measuring the quantity, dimensions, and mass of hydatid cysts in infected murine subjects.

Results

The findings indicated that AOCE, particularly at a concentration of 45.0 mg/mL, effectively eliminated protoscoleces of hydatid cysts within a 30-min exposure period. Additionally, AOCE demonstrated prolonged anti-parasitic effects in ex vivo conditions, in contrast to the immediate lethal effects observed in vitro (p < 0.001). AOCE significantly (p < 0.01) induced caspase-3 activation in protoscoleces obtained from hydatid cysts relative to the control normal saline group. Furthermore, the results from Real-time PCR analysis indicated a significant (p < 0.001) upregulation in the expression levels of the EgATM and EgP53 genes following treatment with AOCE. By in vivo, we found that treatment with AOCE mainly at 200 mg/kg significantly (p < 0.001) reduced the number, size, and weight of hydatid cyst relative to the control group treated with normal saline group. Biochemical analysis also demonstrated that administration of AOCE to infected mice, led to a marked improvement and a reduction in serum levels of liver function factors.

Conclusion

The results indicated that AOCE exhibits considerable in vitro and ex vivo scolicidal properties against hydatid cyst protoscoleces. Furthermore, the results highlighted AOCE's capacity to eradicate protoscoleces through the induction of apoptosis and the infliction of DNA damage. Additionally, AOCE demonstrated significant therapeutic efficacy in managing hydatid cysts in murine models. However, further studies are required to clarify the specific mechanisms underlying its action and to assess its efficacy in clinical trials, which may facilitate the application of AOCE in the context of hydatid cyst surgical procedures.

Efficacy and mechanism of action of harmine derivative H-2-104 against Echinococcus granulosus infection in mice

BACKGROUND

Cystic echinococcosis (CE) is a chronic zoonotic parasitic disease caused by the parasite Echinococcus granulosus (E. granulosus). Currently, pharmacologic treatments are limited to albendazole and mebendazole; however, these treatments are associated with significant side effects and limited therapeutic efficacy, highlighting the urgent need for the development of new drugs. Harmine (HM) has been reported to exhibit potent antiparasitic effects, although it is also accompanied by notable neurotoxicity. H-2-104, a derivative of HM obtained through structural modification of its parent nucleus, represents a promising candidate for further investigation. This study aims to assess the in vivo and in vitro efficacy of H-2-104 against E. granulosus and to elucidate the mechanism of action of H-2-104 against CE from a metabolomics perspective.

METHODS

In vitro pharmacodynamics experiments were conducted to assess the inhibitory activity of H-2-104 against E. granulosus protoscoleces (PSCs). Following this, a mouse model of E. granulosus infection was established to explore the inhibitory effects against E. granulosus of H-2-104 at low, medium, and high concentrations. Additionally, non-targeted metabolomic approaches were utilized to analyze the serum and liver samples from mice in the control group, model group, and H-2-104 treatment group with the aim of identifying relevant biomarkers and crucial metabolic pathways involved in the response to H-2-104 treatment.

RESULTS

The in vitro results demonstrated that H-2-104 exhibited significantly superior inhibitory activity against PSCs compared to harmine and albendazole. Morphological observations revealed marked alterations in the ultrastructural characteristics of PSCs treated with H-2-104. In vivo pharmacodynamic studies showed that H-2-104 at a dosage of 100 mg/kg exhibited the highest cyst inhibition rate, which was (73.60 ± 4.71)%. Metabolomics analysis revealed that 64 serum metabolites were significantly altered, primarily involving metabolic pathways such as necroptosis, linoleic acid metabolism, and phenylalanine metabolism. Additionally, 81 liver metabolites were identified with significant differences, mainly involving metabolic pathways like fructose and mannose metabolism, and glycerophospholipid metabolism.

CONCLUSIONS

H-2-104 exhibits significant activity both in vitro and in vivo, suggesting its potential as a promising new drug for the treatment of CE. The anti-CE effects of H-2-104 may be attributed to its regulation of multiple biological pathways, including cell apoptosis, amino acid metabolism, and glucose metabolism.

Bioactivities and Structure-Activity Relationships of Harmine and Its Derivatives: A Review

Natural products and their derivatives play a crucial role in treating various diseases. Harmine, a tricyclic β-carboline alkaloid isolated from the seeds of Peganum harmala L., has emerged as a promising therapeutic candidate owing to its multifaceted biological activities. Recent studies have further highlighted the enhanced therapeutic potential of harmine derivatives. To assess the current research landscape on harmine and its derivatives, we conducted a comprehensive analysis of studies published between 2019 and 2024 in scientific databases, such as PubMed, Web of Science, and Google Scholar. In this review, the possible applications of harmine and its derivatives were systematically illustrated, including biological activities, structure-activity relationships, and nanotechnology applications. Notably, the biological activities of harmine and its derivatives mainly contained antitumor, neuroprotective, antiparasitic, anti-inflammatory, and antidiabetic properties. In addition, structural modifications and the application of nanocarriers make harmine and its derivatives more druggable. The aim of this review is to summarize the recent advancements in harmine and its derivatives research, analyze emerging trends, and explore their clinical value.

In vitro and ex vivo protoscolicidal effect of poly(amidoamine) nanoemulsion against Echinococcus granulosus

Hydatidosis causes a serious health hazard to humans and animals leading to significant economic and veterinary and public health concern worldwide. The present study aimed to evaluate the in vitro and ex vivo protoscolicidal effects of synthesized poly(amidoamine), PAMAM, nanoemulsion. In this study, PAMAM was characterized through dynamic light scattering technique to investigate the particle size and zeta potential of nanoemulsified polymer. For the in vitro and ex vivo assays, we used eosin dye exclusion test and scanning electron microscope (SEM) to evaluate the effects of the prepared and characterized PAMAM nanoemulsion against protoscoleces from Echinococcus granulosus sensu lato G6 (GenBank: OQ443068.1) isolated from livers of naturally infected camels. Various concentrations (0.5, 1, 1.5 and 2 mg/mL) of PAMAM nanoemulsion at different exposure times (5, 10, 20 and 30 min) were tested against protoscolices. Our findings showed that PAMAM nanoemulsion had considerable concentration- and time-dependent protoscolicidal effect at both in vitro and ex vivo experiments. Regarding in vitro assay, PAMAM nanoemulsion had a potent protoscolicidal effect when compared with the control group with a highest protoscolicidal activity observed at the concentration of 2 mg/mL at all exposure times, such that 100% of protoscolices were killed after 20 min of exposure. Also, the mortality of protoscolices was 100% after 30 min of exposure to 1 and 1.5 mg/mL of PAMAM nanoemulsion, in vitro. Concerning ex vivo assay PAMAM nanoemulsion recorded the highest mortality rates at the concentration of 2 mg/mL (55, 99.4 and 100% at 10, 20, 30 min, respectively). Ultrastructure examination of examined protoscolices after 20 min of exposure to PAMAM nanoemulsion showed a complete loss of rostellar hooks, disruption of suckers with disorganization of hooks with partial or complete loss of them, and damage of protoscolices tegument with loss of their integrity in the form of holes and contraction of the soma region were observed in 1.5 and 2 mg/mL of PAMAM, in vitro and ex vivo, showing more damage in the in vitro conditions. It can be concluded that PAMAM nanoemulsion is a promising protoscolicidal agent offering a high protoscolicidal effect at a short exposure time. Further in vivo studies and preclinical animal trials are required to evaluate its efficacy and clinical applications against hydatid cysts.

1,3-Substituted β-Carboline Derivatives as Potent Chemotherapy for the Treatment of Cystic Echinococcosis

Echinococcosis is a global public health issue that generally occurs in areas with developed animal husbandry. In search of safe and effective therapeutic agents against echinococcosis, we designed and synthesized new 1,3-substituted β-carboline derivatives based on harmine. Among them, compounds 1a, 1c, and 1e displayed potent inhibitory activity against Echinococcus granulosus in vitro, significantly better than albendazole and harmine. The morphological detection revealed that 1a, 1c, and 1e significantly changed the ultrastructure of Echinococcus granulosus protoscolices (PSCs). Furthermore, pharmacokinetic studies suggested that 1a possessed a better metabolic property. Encouragingly, 1a exhibited a highest cyst inhibition rate as 76.8% in vivo and did not display neurotoxicity in mice. Further mechanistic research illustrated that 1a has the potential to induce autophagy in PSCs, which may be responsible for the therapeutic effect of the drugs. Together, 1a could be a promising therapeutic agent against echinococcosis, warranting further study.

In vitro and in vivo Efficacies of Novel Harmine Derivatives in the Treatment of Cystic Echinococcosis

Introduction

Cystic echinococcosis (CE) is a chronic zoonotic parasitic disease caused by the larvae of the Echinococcus granulosus sensu lato (s.l.) cluster. The current existing drugs have limited therapeutic efficacy against cystic echinococcosis, and thus, there is an urgent need to develop new drugs.

Methods

In this study, 7 harmine (HM) derivatives were screened and the effects of HM derivatives on E. granulosus sensu stricto (s.s.) were evaluated by in vitro and mouse experiments. The safety of the HM derivatives was assessed by cytotoxicity assays, acute toxicity study in animals and subacute toxicity study.

Results

These results show that the HM derivatives H-2-168 and DH-004 exhibited more significant antiparasitic effects at an initial concentration of 40 μM. The results of further studies showed that H-2-168 and DH-004 had dose-dependent effects against protoscoleces and had satisfactory therapeutic outcomes in vivo. Electron microscopy observations demonstrated that H-2-168 and DH-004 caused severe disruption of the parasite ultrastructure. Notably, the results of the acute toxicity and subchronic toxicity studies showed that H-2-168 and DH-004 had significantly improved safety. In addition, we found that H-2-168 and DH-004 induced DNA damage in E. granulosus s.s., which may be the mechanism by which these drugs produce their therapeutic effects.

Discussion

Overall, the data from this work demonstrate that H-2-168 and DH-004 are highly effective candidate compounds with low toxicity for the treatment of CE and will provide a new therapeutic strategy for CE pharmacological treatment.