Diuretic Effect of Compounds from Hibiscus sabdariffa by Modulation of the Aldosterone Activity

Abstract

Recent studies of Hibiscus sabdariffa Linn. have demonstrated that it presents diuretic, natriuretic, and potassium sparing effects. However, the mechanism that induces these effects has not yet been elucidated. The aim of this study was to explore the possible mechanism of action for the diuretic effect of Hibiscus sabdariffa extract and its fractions.The aqueous extract from this plant and the fractions obtained with solvents of different polarities were administered to adrenalectomized rats, and the diuretic effect was measured in the presence of deoxycorticosterone acetate (aldosterone analog).The effect on renal filtration was also evaluated in an in situ kidney model, and finally, the effect of diuretic active extracts on gene expression of the alpha subunit from the transporter (αENaC) of renal epithelial cell was quantified. The subsequent results were obtained: The aqueous extract of Hibiscus sabdariffa presented the following chemical composition, 32.4 mg/g delphinidin-3-O-sambubioside, 11.5 mg/g cyanidin-3-O-sambubioside, 11.5 mg/g quercetin, and chlorogenic acid 2.7 mg/g. The concentration of anthocyanins was diminished until disappearance due to decrease of the polarity of the solvents used in the extraction process, in contrast to the flavonoids and chlorogenic acid, which had their concentration increased. The diuretic effect caused by adrenalectomy in rats was reversed by deoxycorticosterone acetate activity. However, the effect of deoxycorticosterone acetate was antagonized by spironolactone, the aqueous extract of Hibiscus sabdariffa, and the acetonitrile : methanol 5 : 5 mixture extract, administered orally. A similar effect was observed on renal filtration obtained from the isolated kidney model.When the gene expression levels of αENaC was measured in adrenalectomized rats, it was observed that spironolactone, the aqueous extract of Hibiscus sabdariffa, the acetonitrile : methanol 5 : 5 mixture, as well as the acetonitrile extract significantly decreased the expression of this protein.The conclusion of this work is that the diuretic, natriuretic, and potassium sparing effects of Hibiscus sabdariffa are due in part to the modulation of aldosterone activity by the presence in the extract of this plant of compounds potentially responsible for this modulation, as anthocyanins, flavonoids, and chlorogenic acid.

Managing Hypertension by Polyphenols

“…Inflammation, endothelial dysfunction, and oxidation are apparently interrelated mechanisms that play a substantial role in the pathogenesis of hypertension [55]. Effects on diuresis should be added to these mechanisms [56]. We have also found that the HS extract strongly inhibits xanthine oxidase, a superoxide-producing enzyme, and 15-lipoxygenase, which may control the formation of eicosanoids in inflammatory cells [9].…”

Identification and Characterization of Roseltide, a Knottin-type Neutrophil Elastase Inhibitor Derived from Hibiscus sabdariffa

“…Its rose-color petals are used in drinks as food coloring and its fruit is used to make fruit preservatives, syrups, and jams. As a traditional medicine, roselle is primarily used as a remedy for coughs2 but is also used as anti-hypertensive34, anti-hyperlipidemia56, anti-nociceptive, anti-pyretic, anti-inflammatory7, and diuretic agents89. Previous studies have shown that the roselle calyx extract contains proteinase inhibitors against angiotensin I converting enzyme, elastase, trypsin, and alpha-chymotrypsin10; however, the chemical nature of these proteinase inhibitors remains unexplored.…”

Therapeutic Effectiveness of an Herbal Medicinal Product of Hibiscus sabdariffa in Hypertensive Patients: A 16 Week Controlled and Randomized Clinical Study

“…HMPHs nocturnal administration did not take into account the diuretic effect of the H. sabdariffa extract [7,8,13], which caused, in some patients, side effects in terms of mainly increasing nocturnal urinary frequency and discontinuous sleep. Due to this effect collateral, the nocturnal administration of the H. sabdariffa extracts must be contraindicated.…”

“…These data confirm that the antihypertensive activity of H. sabdariffa extracts, standardized between 200-250 mg of TAC, is consistent and reproducible, although the extract employed in the HMPHs formulations would have a different polarity. Therefore, it can be hypothesized that in H. sabdariffa extracts, there are other compounds that possess antihypertensive activity, mainly polyphenols and flavonoids, with different antihypertensive mechanisms of action [8,11,13]. Figure 5 compares the percentages of therapeutic effectiveness achieved with both treatments during 16 weeks.…”