Antitoxin activity of aqueous extract of Cyclea peltata root against Naja naja venom

Phytochemical characterization and phospholipase A2 inhibitory effect of Vitex negundo L. root extracts

ETHNOPHARMACOLOGICAL RELEVANCE

Snake bites are a critical health issue in many parts of the world particularly in Asian countries lacking efficient health facilities in rural areas. Cobra is the most common snake type in Asia and is responsible for a large number of mortalities particularly in rural areas. Plants are usually considered the most effective and easy-to-approach treatment for snake bites in rural areas of various countries. Vitex negundo L. is an important medicinal plant traditionally used to treat snake bite envenomation in many countries of Asia.

AIM OF THE STUDY

From literature survey of plants traditionally used in the treatment of snake bites in Asian countries including India, Pakistan and Sri Lanka, roots of V. negundo were selected for the present study. Anti-snake venom potential of its roots was assessed through various in vitro assays targeting the phospholipase A2 enzyme.

MATERIALS AND METHODS

V. negundo roots were sequentially extracted in different organic solvents to get fractions and in methanol to get total extract. The extracts were evaluated for phospholipase A2 (PLA2) inhibitory potential through inhibition of venom-induced hemolysis, ADP-induced platelet aggregation, PLA2-induced fatty acid hydrolysis and anticoagulant effect of cobra venom. Antioxidant power was determined using DPPH and superoxide radical scavenging assays. GC-MS and HPLC analysis was performed for the total methanol extract.

RESULTS

Strong PLA2 inhibitory effect was observed for all the extracts. The ethyl acetate, acetone and methanol fractions significantly inhibited toxic effects of cobra venom under in vitro conditions. Radical scavenging potential of these fractions was also significantly high as compared to non-polar fractions in both DPPH and superoxide scavenging assays. Phytochemical analysis indicated high phenolic and flavonoid contents in these fractions. GC-MS and HPLC analysis of total methanol extract confirmed the presence of bis(2-ethylhexyl) phthalate, phenol, o-Guaiacol, palmitic acid-methyl ester, methyl stearate, quercetin and kaempferol in the plant.

CONCLUSION

The study concluded that the roots of V. negundo, particularly their polar extracts, have strong PLA2 inhibitory effect against cobra venom confirming their traditional use to manage snake bites. The roots of this plant can be further studied for isolation of plant-based antisera.

Prospecting Local Treatments Used in Conjunction with Antivenom Administration Following Envenomation Caused by Animals: A Systematic Review

Envenomation caused by venomous animals may trigger significant local complications such as pain, edema, localized hemorrhage, and tissue necrosis, in addition to complications such as dermonecrosis, myonecrosis, and even amputations. This systematic review aims to evaluate scientific evidence on therapies used to target local effects caused by envenomation. The PubMed, MEDLINE, and LILACS databases were used to perform a literature search on the topic. The review was based on studies that cited procedures performed on local injuries following envenomation with the aim of being an adjuvant therapeutic strategy. The literature regarding local treatments used following envenomation reports the use of several alternative methods and/or therapies. The venomous animals found in the search were snakes (82.05%), insects (2.56%), spiders (2.56%), scorpions (2.56%), and others (jellyfish, centipede, sea urchin-10.26%). In regard to the treatments, the use of tourniquets, corticosteroids, antihistamines, and cryotherapy is questionable, as well as the use of plants and oils. Low-intensity lasers stand out as a possible therapeutic tool for these injuries. Local complications can progress to serious conditions and may result in physical disabilities and sequelae. This study compiled information on adjuvant therapeutic measures and underscores the importance of more robust scientific evidence for recommendations that act on local effects together with the antivenom.

Exploration of Phaeanthine: A Bisbenzylisoquinoline Alkaloid Induces Anticancer Effect in Cervical Cancer Cells Involving Mitochondria-Mediated Apoptosis

Natural-product-based pharmacophores possess considerably more structural diversity, attractive physicochemical features, and relatively less toxicity than synthesized drug entities. In this context, our studies on phaeanthine, a bisbenzylisoquinoline alkaloid isolated from the rhizomes of Cyclea peltata (Lam) Hook.f & Thoms., showed selective cytotoxicity toward cervical cancer cells (HeLa) with an IC₅₀ of 8.11 ± 0.04 μM. Subsequent investigation with in silico molecular docking of phaeanthine displayed preferential binding to the antiapoptotic protein Akt as reflected by a docking score of -5.023. Interestingly, the follow-up in vitro assessment of the compound correlated with mitochondria-mediated apoptosis specifically by downregulating the expression of Akt and p-Akt, including other antiapoptotic proteins MCl-1, IGF-2, and XIAP. In the complementary in vitro assessment, mitochondrial membrane polarization and dynamics of intercellular cytochrome c validated the intrinsic mechanism of the apoptotic phenomenon. To the best of our knowledge, this is the first comprehensive anticancer profiling study of phaeanthine against HeLa cells.

In vitro anti-venom potential of various solvent based leaf extracts of Andrographis serpyllifolia (Rottler ex Vahl) Wight against Naja naja and Daboia russelli

ETHNOPHARMACOLOGICAL RELEVANCE

Snake bite is a major occupational hazard in tropical and subtropical countries including India as per the World Health Organization. Naja naja (Indian cobra) and Daboia russelli (Russell's viper) are the two poisonous snakes commonly associated with human mortality in India. Andrographis serpyllifolia (Rottler ex Vahl) Wight has been documented in ethnobotanical records as a plant possessing potent anti-snake venom activity.

AIM OF THE STUDY

The present study is aimed for systematic evaluation of in vitro anti-venom potential of various solvent based leaf extracts of A. serpyllifolia against toxic venom enzymes of Naja naja and Daboia russelli.

MATERIALS AND METHODS

Different solvent based leaf extracts of A. serpyllifolia were tested against the snake venoms of Naja naja and Daboia russelli obtained from Irula Snake Catchers Industrial Co-operative Society Limited, Kancheepuram, Tamil nadu, India. Three different in vitro neutralization assays such as indirect hemolysis, procoagulent and lytic activities and seven in vitro enzyme inhibition assays such as protease, acetylcholinesterase, phosphomonoesterase, phosphodiesterase, 5'nucleotidase, phospholipase A2, hyaluronidase and post synaptic acetylcholine receptor binding activity were carried out according to standard protocols. The results were analyzed using the standard ANOVA procedures.

RESULTS

Among various solvent based leaf extracts of A. serpyllifolia tested, aqueous extract showed maximum neutralizing and inhibitory activities against Naja naja and Daboia russelli venoms.

CONCLUSIONS

The various in vitro enzymatic studies reveal that the aqueous leaf extract of A. serpyllifolia plant could inhibit most of the toxic enzymes of the Naja naja and Daboia russelli venoms which could be further confirmed by in vivo studies.

Anti-Deinagkistrodon acutus venom properties of ethanolic root extract from Cynanchum paniculatum (Bunge) kitag and its GC-MS analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum paniculatum (Bunge) Kitag known as a popular Chinese herbal medicine has been used for a long time to treat a wide variety of diseases including snakebites. However, there is scarce information on the antiophidian potential of this plant.

AIM OF THE STUDY

The purpose of this work was to evaluate the inhibition effects of the ethanol extract of C. paniculatum on the enzymatic and biological activities induced by Deinagkistrodon acutus venom (DAV). The phytochemical components in the extract were also determined for understanding the mechanism of antivenom activities.

MATERIALS AND METHODS

Fresh root of C. paniculatum was shed-dried and smashed into powder. The powder was then extracted in 75% ethanol by refluxing method. Inhibition of proteolytic, phospholipase A₂, fibrinogenolytic and hyaluronidase activities of DAV by the extract were determined in vitro. Neutralization of lethal, hemorrhagic, myotoxic and edematogenic activities induced by the venom were also performed in vivo. Phytochemical constituents of the extract were analyzed by gas chromatography-mass spectrometry (GC-MS).

RESULTS

The ethanolic root extract of C. paniculatum (CPER) was able to completely (100%) inhibit protease and hyaluronidase activities induced by DAV when preincubated at a ratio of 1:100 and 1:50 (venom/extract, W/W), respectively. PLA₂ and fibrinogenolytic enzyme activities were actually neutralized at the concentration tested. In-vivo studies the inhibition of venom hemorrhagic and myotoxic action reached 100% when the venom was previously incubated with the extract (1:100) before injection. The edematogenic effect was also inhibited in a dose-response manner. CPER completely inhibited DAV-induced lethality in mice when the venom was preincubated with the extract at a ratio of 1:100. GC-MS analysis indicated that a total of 58 compounds were discovered in CPER. Among them, 5 bioactive constituents including 9,12-octadecadienoic acid (Z,Z)-, n-hexadecanoic acid, cis-vaccenic acid, γ-sitosterol and stigmasterol exhibit antivenom activity according to previous reports.

CONCLUSIONS

The results obtained in this work validate for the first time CPER as a traditional antiophidic herb, especially inhibitory effect on local damage induced by DAV, suggesting it could be used as a potential source of bioactive components against snakebites.