Investigation Of Extracts of Zappania Urticifolia for Antiepiletic Activity in Mes and Induced Epilepsy in Experimental Rats

One of the most common neurological disorders in the world is epilepsy, which causes the disorder in about 50 million people and is a significant significant issue to the community. It is typified by repeated and unprovoked seizures caused by abnormal electrical activities in the brain [1]. Even though there are a number of available antiepileptic drugs (AEDs), approximately one-third of the patients are refractory or show serious side effects of undergoing long-term treatment, and safe and effective therapeutic alternatives that are more effective are highly demanded [2,3].

Plant-based remedies have been used in the traditional medicinal systems to manage various neurological diseases such as epilepsy. Bioactive secondary metabolites, including flavonoids, alkaloids, terpenoids, and glycosides, are abundant in medicinal plants and most of them exhibit neuroprotective and anticonvulsant effects [4,5]. The increasing popularity of herbal medicines all over the world is strongly contributed by the fact that these medicines are perceived to be safe, cheap and have broad therapeutic applications [6].

Zappania urticifolia (Family: Verbenaceae), also referred to as blue snake weed or nettle leaf velvet berry is a perennial herb that was very common in the tropical and subtropical areas. The plant has been used in the traditional treatment of fever, inflammatory diseases, gastrointestinal diseases and infection [7,8]. Phytochemical studies have identified the existence of iridoid glycosides, sterols, flavonoids, and phenolic compounds in the different parts of the plant and this indicates its possible pharmacological value [9].

Although it has been reported to have antioxidant, antimicrobial and cytotoxic properties, there is limited scientific evidence to support the antiepileptic effects of Zappania urticifolia [10,11]. Thus, the current experiment was done to provide systematic assessment of the antiepileptic effect of methanolic and aqueous leaf extracts of Zappania urticifolia on conventional experimental seizure models, which would provide pharmacological endorsement to its traditional usage. Phytochemical studies have indicated the occurrence of iridoid glycosides, sterols, flavonoids and phenolic compounds in different parts of the plant,

 

 

Fig – 1 Indicates Schematic representation on Zappania urticifolia

 

 

Fig – 2 represents effect of MZU on rats

Tab-1 Indicates Effect on Maximal Electroshock (MES)-Induced Seizures

Group	Design of treatment	Flexion	Extensor	Clonus	Stupor	Recovery	% protection
I	Vehicle control	8.90.32	12.210.03	18.780.32	38.20.58	189.2	0
II	Phenytoin 2.5mg/kg. i.p.	3.90.33 **	0**	8.910.5 4**	16.290. 35*	93.5	100
III	MZU 250mg/kg .p.o	6.720.5 1*	3.920.1 6**	14.810. 36*	31.580. 95	141.79	66.31
IV	MZU 500mg/kg .p.o	4.090.2 2**	2.120.3 1**	12.820. 85**	16.230. 69*	113.51	82.731
V	AZU 250mg/kg .p.o	7.040.3 5*	4.510.1 9**	17.550. 39*	34.390. 54	146.21	63.56

 

 

 

Fig – 3  represents effect of zappania urticifolia exctracts on MES- induced seizures

 

 

Fig – 4 Determines Pentylenetetrazole (PTZ)-Induced Seizures

DISCUSSION

The current research paper shows that the methanolic and aqueous leaf extracts of Zappania urticifolia have a large antiepileptic effect on the electrically and chemically induced seizure models. The application of MES and PTZ models offers full understanding of the anticonvulsant capability of the plant because these models replicate the various seizure types and processes that have been witnessed in the human epilepsy.

MES model is extensively used to detect the agents that are effective against the generalized tonic-clonic seizures and propagation of seizures. The tonic hind limb extension is suppressed by drugs in this model, which is thought to be inhibitory by blocking neural tissue voltage-gated sodium channels or inhibiting the propagation of the seizure by preventing neural tissue [22]. Such significant decrease in tonic hind limb extension by Zappania urticifolia extracts indicate a potential modification of sodium channel activity or neuronal membrane stabilization.

The seizure model generated by the PTZ is typically applicable in the determination of compounds that are effective against absence and myoclonic seizures. PTZ causes seizures mostly by blocking GABA A receptors which blocks inhibitory neurotransmission of the brain [23]. The delay in seizure onset and decrease in seizure duration in the case of Zappania urticifolia extracts suggest the potential increase in GABAergic transmission or the inhibitory synaptic activity.

This is because the anthaconvulsant activity of the methanolic extract is higher than that of the aqueous extract; this could be explained by the fact that lipophilic bioactive compounds like flavonoids, alkaloids, and terpenoids have higher solubility in methanol. Flavonoids are also known to bind to benzodiazepine receptors of the GABA receptors and act as anxiolytic and anticonvulsant agents [24]. It is also known that alkaloids can regulate the release of neurotransmitters and ion channels activity, a fact that also helps in suppressing seizures [25].

Also, oxidative stress has been implicated in the etiology of epilepsy, and neuronal pathology of repetitive fainting. Phenolic compounds and flavonoids occur in Zappania urticifolia which could be part of its antioxidant activity and thus provide neuroprotection and decrease the severity of seizures [26]. Therefore, the antiepileptic effect demonstrated in this paper can possibly be due to synergistic effect of many phytoconstituents with various mechanisms.

Despite the solid pharmacological evidence that the conventional use of Zappania urticifolia in the treatment of neurological disorders, additional studies should be conducted in order to isolate the active constituents, clarify the specific mechanisms, and determine long-term safety measures.

CONCLUSION

The current study shows that Zappania urticifolia leaf extracts (methanolic and aqueous) have considerable antiepileptic effects in test seizure models. The methanolic extract, especially, was more effective in the inhibition of the seizure onset and duration, which means that it has a higher proportion of pharmacologically active components. The anticonvulsant effects are possibly mediated by the action via the regulation of the GABAergic neurotransmission, inhibition of seizure propagation, and antioxidant processes.

The results offer scientific support of the conventional application of Zappania urticifolia in the treatment of epilepsy and shows its possibility as the source of new antiepileptic medications. More pharmacological and clinical research is needed to isolate active compounds, their mechanism of action and therapeutic potential on the management of epilepsy.

Limitations

The current experiment only focused on the acute experimental seizure models and might not be representative of the complicated processes that occur in the case of chronic epilepsy in humans. Crude methanolic and aqueous extracts were tested on the antiepileptic activity and the exact bioactive constituents that resulted in the observed effects were not isolated and characterized. The evidence of mechanistic understanding was indirectly obtained with the help of seizure models because no molecular or receptor-based research was conducted. Further, the chronic toxicity, pharmacokinetic and possible interactions with the traditional antiepileptic drugs have not been resolved, restricting the direct clinical application of the results.

FUTURE DIRECTIONS

The isolations, characterization and structural elucidation of the bioactive phytoconstituents in Zappania urticifolia that cause its antiepileptic properties should be the main focus of future research. Differentiation of lead compounds with better potency and selectivity can be achieved with the help of bioassay-guided fractionation. It is justified to conduct further studies based on the chronic seizure models (kindling and genetic models of epilepsy), to assess the effectiveness of the plant over time and whether it can be involved in the regulation of epileptogenesis and recurrence of seizures.

Mechanistic studies with molecular, electrophysiological, and receptor-binding techniques are required to clarify the specific mechanisms that are involved in the suppression of seizures, especially those in GABAergic and glutamatergic neurotransmission, the control of ion channels and oxidative stress. Also, full toxicity profiling, pharmacokinetic analysis, and herb-drug interactions should be analyzed to determine safety and translation relevance. Finally, to prove these preclinical results and to justify the creation of Zappania urticifolia as a new plant-based antiepileptic treatment, the well-designed clinical studies will be needed.

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