In vitro and in vivo anthelmintic effects of Caesalpinia bonducella (L.) Roxb. leaf extract on Hymenolepis diminuta (Cestoda) and Syphacia obvelata (Nematoda)

Evaluation of anthelmintic efficacy of ethanolic leaf extract of Juglans regia L. on Ascaridia galli: a comprehensive in vitro and in vivo study

Anthelmintic resistance in livestock animals has been spreading across the world in prevalence and severity. As a result, researchers are exploring alternative strategies to combat this issue, and one promising avenue is the utilization of medicinal plants. This study aims to investigate the anthelmintic efficacy of the crude ethanolic extract (CEE) derived from the leaves of Juglans regia against one of the most detrimental nematode parasites affecting poultry, namely Ascaridia galli (A. galli). For the in vitro studies, adult A. galli worms were collected from the naturally infected chickens and the efficacy of CEE was measured at the concentration of 25, 50, and 100 mg/ml using adult worm motility inhibition (WMI) assay. In addition, levamisole (0.55 mg/ml) was used as the positive control. Likewise, Phosphate buffered saline (PBS) was used as the negative control. For the in vivo studies, CEE of J.regia at the doses of 500, 1000, and 2000 mg/kg were evaluated in chickens experimentally infected with A. galli. The anthelmintic efficacy was monitored using faecal egg count reduction (FECR) and worm count reduction (WCR) assays. In vitro studies revealed significant (P < 0.001) anthelmintic effects of CEE of J.regia on the motility of A. galli worms at different hours post-exposure. At the concentration of 100 mg/ml, CEE resulted in 96.5% inhibition of worm motility at 24 h post-exposure. While the synthetic anthelmintic drug, levamisole caused the highest inhibition of worm motility (100%) at the same time period. The in vivo anthelmintic activity of CEE of J. regia demonstrated a maximum effect on day 14 post-treatment by inducing 67.28% FECR and 65.03% WCR. We observed no significant difference (P > 0.05) in worm counts between the negative control group and the chickens treated with CEE at the dosage of 500 mg/kg. Together, the results of the present study suggest that CEE of J. regia leaves possess anthelmintic properties and could be a potential source of novel anthelmintic compounds for controlling helminth parasites.

Botany, traditional usages, phytochemistry, pharmacology, and toxicology of Guilandina bonduc L.: a systematic review

Guilandina bonduc L. is popularly known as a fever nut that grows widely in evergreen forests and moist deciduous forests with a pantropical distribution. The plant is highly therapeutic in various systems of medicine, including Ayurveda, Siddha, and homeopathy. The purpose of this review is to analyze the published data on G. bonduc, including traditional uses, taxonomic position, botanical description, phytochemistry, pharmacological properties, and toxicological assessment of its various parts. Phytochemical and pharmacological studies were the main focus of this review. The previously published research on G. bonduc was tracked from scientific databases such as Online Library, Google, Taylor and Francis, PubMed, Research Gate, Scopus, Springer, Wiley, Web of Sciences. Numerous phytochemical, pharmaceutical, and pharmacological studies have been carried out on the various parts of G. bonduc. To date, more than 97 phytochemicals have been isolated from the leaves, roots, stems, stem bark, flowers, twigs, and seeds of this plant. The phytochemicals isolated from the plants are flavonoids, homoisoflavonoids, terpenoids, diterpenoids, steroids, fatty acids, alkanes, acids, phenols, ketones, esters, amides, azides, silanes, and ether groups. This plant has been extensively studied in in vitro and in vivo pharmacological experiments, where it showed analgesic, anti-inflammatory, antioxidant, antiviral, antidiabetic, abortive, anticataleptic, immunomodulatory, and antiestrogenic effects. This comprehensive review revealed that phytochemicals isolated from various parts of G. bonduc have significant therapeutic efficacy, with promising anticancer, antidiabetic, hepatoprotective, antioxidant, and antimicrobial activities. This review provides a good source of information for the development of a drug using modern scientific tools, in view of its underexplored traditional uses. Further studies on preclinical and clinical trials and toxicological studies on the bioactive molecules of G. bonduc to validate its traditional uses are warranted.

Anthelmintic efficacy of Phlogacanthus thyrsiflorus leaf extract on juvenile and adult worms of Hymenolepis diminuta (Cestoda)

The leaves of Phlogacanthus thyrsiflorus are used as an anthelmintic remedy by the tribal communities of upper Assam in India. The present study was carried out to validate the anthelmintic credentials of this plant. Mature and larval Hymenolepis diminuta worms were exposed to varying concentration of methanolic leaf extract of plant and parasites were observed for paralysis and mortality. At the end of the experiment, worms were collected and processed for scanning electron microscopy (SEM) study to observe the effect of extract on tegument of parasite. The in vivo study was carried out in H. diminuta-rat model with 200, 400 and 800 mg/kg concentrations of extract. The in vivo anthelmintic efficacy was assessed by reductions in egg per gram (EPG) and worm counts after necropsy of animals. In vitro studies revealed the earliest mortality of larval worms in 1.05 ± 0.04 h by 30 mg/ml concentration and of adult worms in 2.05 ± 0.08 h. SEM study revealed extensive damage to the suckers, body tegument and microtriches of worms treated with 30 mg/ml concentration of extract. In in-vivo studies, 800 mg/kg dose of extract showed highest efficacy, with 59% and 54.25% reduction in EPG counts and worm count against juvenile worms, and 63.16% and 66.75% reduction in EPG counts and worm counts, respectively against adult worms. Although the effects were comparatively less than the reference drug, nevertheless this study reveals that P. thyrsiflorus possess anthelmintic efficacy and justify its use in traditional medicine against intestinal-worm infections.

Model nematodes as a practical innovation to promote high throughput screening of natural products for anthelmintics discovery in South Asia: Current challenges, proposed practical and conceptual solutions

With the increasing prevalence of anthelmintic resistance in animals recorded globally, and the threat of resistance in human helminths, the need for novel anthelmintic drugs is greater than ever. Most research aimed at discovering novel anthelmintic leads relies on high throughput screening (HTS) of large libraries of synthetic small molecules in industrial and academic settings in developed countries, even though it is the tropical countries that are most plagued by helminth infections. Tropical countries, however, have the advantage of possessing a rich flora that may yield natural products (NP) with promising anthelmintic activity. Focusing on South Asia, which produces one of the world's highest research outputs in NP and NP-based anthelmintic discovery, we find that limited basic research and funding, a lack of awareness of the utility of model organisms, poor industry-academia partnerships and lack of technological innovations greatly limit anthelmintics research in the region. Here we propose that utilizing model organisms including the free-living nematode Caenorhabditis elegans, that can potentially allow rapid target identification of novel anthelmintics, and Oscheius tipulae, a closely related, free-living nematode which is found abundantly in soil in hotter temperatures, could be a much-needed innovation that can enable cost-effective and efficient HTS of NPs for discovering compounds with anthelmintic/antiparasitic potential in South Asia and other tropical regions that historically have devoted limited funding for such research. Additionally, increased collaborations at the national, regional and international level between parasitologists and pharmacologists/ethnobotanists, setting up government-industry-academia partnerships to fund academic research, creating a centralized, regional collection of plant extracts or purified NPs as a dereplication strategy and HTS library, and holding regional C. elegans/O. tipulae-based anthelmintics workshops and conferences to share knowledge and resources regarding model organisms may collectively promote and foster a NP-based anthelmintics landscape in South Asia and beyond.

The Tapeworm Hymenolepis diminuta as an Important Model Organism in the Experimental Parasitology of the 21st Century

The tapeworm Hymenolepis diminuta is a common parasite of the small intestine in rodents but it can also infect humans. Due to its characteristics and ease of maintenance in the laboratory, H. diminuta is also an important model species in studies of cestodiasis, including the search for new drugs, treatments, diagnostics and biochemical processes, as well as its host-parasite interrelationships. A great deal of attention has been devoted to the immune response caused by H. diminuta in the host, and several studies indicate that infection with H. diminuta can reduce the severity of concomitant disease. Here, we present a critical review of the experimental research conducted with the use of H. diminuta as a model organism for over more than two decades (in the 21st century). The present review evaluates the tapeworm H. diminuta as a model organism for studying the molecular biology, biochemistry and immunology aspects of parasitology, as well as certain clinical applications. It also systematizes the latest research on this species. Its findings may contribute to a better understanding of the biology of tapeworms and their adaptation to parasitism, including complex correlations between H. diminuta and invertebrate and vertebrate hosts. It places particular emphasis on its value for the further development of modern experimental parasitology.

Antifilarial Activity of the Methanolic Extract of Indigofera tinctoria (Fabaceae) on Bovine Parasites (Onchocerca ochengi)

Onchocerciasis is a major public health problem caused by Onchocerca volvulus parasite and transmitted to humans via black flies (simulium) bites. The control of onchocerciasis relies much on the use of the chemical drug ivermectin, which is only effective against microfilariae and has led to drug resistance. This study was carried out to assess the in vitro antifilarial activity of methanolic extract of Indigofera tinctoria and its most active fractions on adult male O. ochengi worm, the closest model to O. volvulus, after 48 h and 72 h of treatment. Worms' viability was determined biochemically by MTT/formazan colorimetry assay. The promising plant extract's acute and subacute oral toxicity were evaluated on both mice and rats. The result revealed a highest antifilarial activity of the methanolic extract (LC50 = 12.28 μg/mL) compared to ivermectin (LC50 = 26.50 μg/mL) after 72 h of treatment. Out of the eight (08), chromatographic fractions screened, only three (03) fractions (C, F, and G) revealed the highest anti-Onchocerca activity after 72 h of treatment. An oral administration of the plant extract at a single dose of 2000 mg/kg did not produce any toxicity in mice. After repeated daily administration of methanolic extract of I. tinctoria (250 mg/kg, 500 mg/kg, and 1000 mg/kg) for 28 days, no significant changes in body weight, biochemical, and haematological parameters was observed. Histopathological examination of organs did not reveal any sign of alteration. The phytochemical analysis of the methanolic extract of I. tinctoria revealed the presence of various phenolic compounds. Therefore, this study demonstrated the potential antifilarial activity of Indigofera tinctoria and offered an alternative to treating onchocerciasis. Moreover, further studies could be developed in promising new antifilarial sources of the isolated compound and in vivo antifilarial activity of Indigofera tinctoria in the animal model needs to be studied.

Persicaria strigosa (R.Br.) Nakai: a natural anthelmintic?

Persicaria strigosa (R.Br.) Nakai. (Family Polygonaceae) is an important plant of Assam, having several ethnobotanical uses. Tribal communities consume leaf extracts to cure helminth infection. The present study investigated the antioxidant, phytochemicals, and anthelmintic activity of P. strigosa. Total phenolic and flavonoid contents were estimated following standard methods. Antioxidant properties were analyzed by TAC, FRAP, DPPH, ABTS, and TBARS assays. Anthelmintic activity of plant was investigated in Paramphistomum sp. treated with 5 mg/mL, and paralysis and death times were recorded. The most potent solvent extract was performed GC-MS analysis to identify the phytocompounds. Plant extract-treated parasites were further analyzed for biochemical changes. Additionally, molecular docking was performed to study the binding affinities between phytocompounds and enzymes. P. strigosa showed rich phenolics, flavonoids, and antioxidant properties. Ethyl acetate and methanolic extracts showed more powerful antioxidant properties than other extracts. In vitro anthelmintic study found ethyl acetate and diethyl ether the most active extracts. Treated parasites showed a significant decrease in enzyme activity. The highest inhibition was observed in AchE, followed by MDH, LDH, ALP, and ACP. GC-MS study identified 12 probable compounds from the ethyl acetate extract of P. strigosa. Molecular docking showed the strongest binding affinity between the phytocompounds and AchE enzyme (- 7.6 kcal/mol). Overall, compounds C6, C7, and C12 showed better binding affinity compared to other compounds. The in vitro helminth bioassays and biochemical analysis suggest Persicaria strigosa a possible anthelmintic agent. However, isolation and characterization of bioactive compound(s) may promise new drug candidates for helminth infections.

Studies on the anthelmintic potentials of the roots of Asparagus racemosus willd. (Asparagaceae)

Background

The Santhal tribe in Assam, India use the roots of Asparagus racemosus (Asparagaceae) as a deworming remedy. The study aimed to investigate the anthelmintic credentials of this plant, using two representative groups of helminth parasites.

Methods

The in vitro testing was conducted against Hymenolepis diminuta (cestode) and Syphacia obvelata (nematode). Parasites were exposed to 10, 20 and 30 mg/ml concentrations of plant extract, and efficacy was adjudged on the basis of parasites paralysis and mortality. In vivo efficacy was examined using H. diminuta-rat and S. obvelata-mice models where animals were administered 125, 250 and 500 mg/kg doses of extract.

Results

In vitro assay, against H. diminuta revealed that at 30 mg/ml concentration the extract showed almost a comparable efficacy with that of reference drug praziquantel (PZQ) (1 mg/ml). The in vitro efficacy of extract against S. obvelata was however lower than H. diminuta. In vivo studies against H. diminuta at 500 mg/kg revealed 53.88 and 24 % reduction in eggs per gram (EPG) and worm counts respectively. Against S. obvelata the extract showed 26.61 and 30.93 % reduction for the same.

Conclusions

The findings of this study present suggest that the roots of A. racemosus are effective against intestinal helminthic infections and justifies its use as an anthelmintic in the traditional medicine of the Santhals.

In vitro and in vivo anthelmintic study of Sesbania sesban var. bicolor, a traditionally used medicinal plant of Santhal tribe in Assam, India

The leaf decoction of Sesbania sesban var. bicolor is used traditionally by Santhal tribe of Assam, India, for the treatment of intestinal helminthic infections. This study was conducted to evaluate the in vitro and in vivo anthelmintic efficacy of methanolic extract of S. sesban var. bicolor leaves using Hymenolepis diminuta-rat (cestode) and Syphacia obvelata-mice (nematode) as test parasites and models. Praziquantel (PZQ) and albendazole (ABZ) were used as reference drugs. At the highest concentration of 30 mg/ml of the plant extract, H. diminuta and S. obvelata showed mortality at 0.81 ± 0.01 h and 15.17 ± 0.05 h, respectively. The in vivo results substantiated the in vitro findings, and the extract showed a better cestocidal efficacy in a dose-dependent manner, whereby treatment of rats with 400 mg/kg of the plant extract caused 65.10% reduction in eggs per gram (EPG) of faeces and 56% reduction in worm counts. S. obvelata-infected mice treated at the same dose showed 34.32% and 47.08% reduction in EPG and worm counts at necropsy, respectively. The methanolic extract was subjected to bioassay-guided fractionation using different solvents and the ethyl acetate fraction proved to be the most active. This active fraction was subjected to column chromatography using varying concentrations of hexane:ethyl acetate. Maximum efficacy was observed in 7:3 hexane:ethyl acetate, where H. diminuta and S. obvelata showed mortality at 3.56 ± 0.12 h and 9.21 ± 0.02 h, respectively. This indicates that the isolated fraction contained the active component responsible for its anthelmintic activity, which substantiates the medicinal usage in traditional practice.

Evaluation of in vitro and in vivo anthelmintic efficacy of Cyperus compressus Linn., a traditionally used anthelmintic plant in parasite-animal models

Background

The decoction of the roots of Cyperus compressus (Cyperaceae) is used to treat helminth infection by the Santhal tribe of Assam. The study evaluated the anthelmintic efficacy claims of the plant C. compressus through pre-clinical in vitro and in vivo studies employing available parasite-animal models such as Hymenolepis diminuta-Wistar rat (cestode) and Syphacia obvelata-Swiss mice (nematode) models.

Results

Phytochemical analysis revealed the presence of alkaloids, glycosides, reducing sugars, flavonoids, terpenoids, tannins, and steroids. In vitro studies were conducted employing H. diminuta and S. obvelata. In vitro studies against H. diminuta revealed mortality of parasites at 8.3 ± 0.05 h at the highest concentration of C. compressus methanolic root extract (30 mg/ml), whereas reference drug praziquantel (PZQ), showed mortality at 5.84 ± 0.01 h. Against S. obvelata, in the same concentration of the extract, mortality of parasites occurred in a much later time of 24.13 ± 0.03 h, whereas in the reference drug albendazole (ABZ), the parasites showed mortality at 7.24 ± 0.08 h. In vivo studies against H. diminuta revealed 61.74% reduction in the eggs per gram (EPG) counts and 24% reduction in worm counts at the highest dose of 700 mg/kg body weight (b.w.) of plant extract. Against S. obvelata, at 700 mg/kg b.w., 28.92% and 33.85% reduction in EPG and worm counts were recorded respectively.

Conclusion

Although the reference drugs showed better in vitro and in vivo efficacy, the plant extract showed a better in vitro efficacy against cestode parasite compared to its nematode counterpart indicating that it possesses a better cestocidal efficacy. EPG reductions were higher against H. diminuta, whereas worm count reduction was higher against S. obvelata. The findings justify the use of C. compressus as an anthelmintic in the traditional medicine of the Santhals of India.