Diuretic Activity of Ethanol Extract of Piper attenuatum Leaves Might Be Due to the Inhibition of Carbonic Anhydrase Enzyme:An in vivo and in silico Investigation

Background:Ayurvedic system of medicine is well established for prevention and treatment of renal problems.There are vast number of medicinal plants mentioned in Ayurvedic system of medicine,including Piper attenuatum Buch.-Ham.ex Miq.,which has been known to exhibit diuretic properties.Objective:To investigate possible mechanism and diuretic activity of ethanol extract of P.attenuatum leaves.Methods:Present study reports an in vivo diuretic activity of ethanol extracts of P.attenuatum leaves.Twenty-four Sprague-Dawley male rats were deprived from food and water for 20 h,followed by being divided into four groups to receive normal saline,Furosemide,and two doses of the ethanol extract,respectively.Further,the ethanol extract were subjected for prelimnary phytochemical screening test,and analytical investigation was performed via high-performance thin-layer chromatography(HPTLC),followed by effectiveness exploration of putative bioactive compounds from P.attenuatum against human carbonic anhydrase(hCA)enzyme using molecular docking tool.Results:During phytochemicals screening,several groups of compounds such as amides,terpenoids,proteins,flavonoids,and glycosides have been identified.Further,HPTLC reveals presence of carbohydrates,proteins,amino acids,steroids,alkaloids,flavonoids,tannins,glycosides,and terpenoids.Significant diuretic action was revealed for both 200 mg/kg bw and 400 mg/kg bw of ethanol extract of P.attenuatum leaves.Interestingly,molecular docking analysis demonstrated greater binding affinity of compounds such as Cepharadione A,Nor-cepharadione B,Galbelgin,Crotepoxide,and Pipoxide chlorohydrin out of total 23 studied compounds against hCA isoforms(a key biomarker for diuretic)and score is comparable with standard drug Acetazolamide.Conclusion:It was concluded from the present studies that ethanol extract of P.attenuatum leaves exhibits signifi-cant diuretic activity.The activity may be correlated due to the presence of Cepharadione A,Norcepharadione B,Galbelgin,Crotepoxide,and Pipoxide chlorohydrin as key component responsible for inhibition of hCA isoforms.

Accumulation of biomass and four triterpenoids in two-stage cultured Poria cocos mycelia and diuretic activity in rats

Poria cocos(Schw.) Wolf, an important medicinal and food fungus, is well known in East Asia. Due to growing market demand, long cultivation period, and consumption of pine trunk during cultivation, developing alternative methods for producing P. cocos and/or its active components is of interest. In the present study, the effects of different culture methods on biomass and accumulation of four triterpenoids were investigated. The ethanol extract of fermented mycelium(EFM) was orally administered to rats. Urine output and concentrations of electrolytes(Na^+, K^+, and Cl^-) were measured. Our results showed that mycelia grew better under continuous shaking culture condition(7.5 g DW·L^(-1)), and higher triterpenoid levels were accumulated in two-stage culture(112 mg·L-1, 2.03%). The optimal starting time of static culture for triterpenoid yield was 4^(th) d after shaking culture. Single administration of middle and high dose of EFM significantly increased urine output, Na^+ and Cl^- excretion, and Na^+/K^+ ratio. These results suggested that ethanol extract of cultured mycelia showed significant diuretic activity in rats and two-stage culture of P. cocos could be an alternative way to produce mycelia and triterpenoids.

Phytoconstituents and diuretic activity of Cymbopogon citratus leaf infusions in humans

Objective:To assess the diuretic activity of infusions prepared from Cymbopogon citratus(C.citratus)leaves in healthy volunteers.Methods:One hundred and five subjects(55 men and 50 women)aged 18 to 35 years were randomly assigned to groups set to orally receive infusions prepared from 2,4,or 8 g of C.citratus leaf powder,once daily for 30 d.Urine volume,frequency of urination,urine specific gravity,and plasma and urinary levels of electrolytes were assessed 1 day before(baseline),and at 10 and 30 d after initiation of treatment.Computed diuretic indices were compared between experimental and baseline values.Results:Subjects treated with infusions prepared from C.citratus leaf powder which tested positive for saponins,tannins,flavaniods,phenols,anthraquinones,alkaloids,and deoxy-sugar exhibited a significant increase in indices of diuresis including urine volume,urination frequency,diuretic action,natriuretic and saliuretic indices and renal fractional excretion of electrolytes and metabolic acidosis.A non-significant change in urine specific gravity was observed in all groups.eGFR showed a non-significant increase at Day 10,but decreased significantly(P<0.05)at Day 30.Thiazide and aldosterone secretion indices decreased at Day 10,whereas carbonic anhydrase index increased significantly(P<0.05)at both Days 10 and 30.Conclusions:These results indicate a loop active diuretic action of C.citratus infusion.

Synthesis and biological evaluation of novel derivatives of desloratadine

Series of novel derivatives of desloratadine designed as arginine vasopressin receptor antagonists were synthesized and structurally characterized by melting points,^1H NMR and HRMS.Their in vivo diuretic activities were evaluated on rats,and several target compounds showed promising diuretic results, especially compounds 8,18,27 and 31.Further in vitro bonding assay and cAMP assay showed that these compounds had a higher affinity to vasopressin V2 receptor than VI a receptor.Our studies indicated that desloratadine may be an active substructure for novel arginine vasopressin receptor antagonist development.