Steviol effect, a glycoside of Stevia rebaudiana, on glucose clearances in rats

Abstract

Stevia rebaudiana, a South American plant normally used as a natural herbal sweetener, has been suggested as exerting beneficial effects on human health, including as an antihypertensive and antihyperglycemic. The present experiment was undertaken to evaluate the renal excretion of steviol, the aglycone of several natural products extracted from the leaves of S. rebaudiana, and to clarify the actual participation of this compound on the renal excretion of glucose in rats, which has been previously suggested as the preferential action of steviol on the Na + -glucose renal tubular transport system. Steviol was obtained by enzymatic hydrolysis of stevioside with pectinase. Thirty normal male Wistar rats weighing 345 g were used. After a control period, steviol was infused iv at three doses (0.5, 1.0 and 3.0 mg.kg -1 /h), according to classical clearance techniques. During all the experiments no significant changes in inulin clearance (C in ) and p-aminohipuric acid clearance (C PAH ) were observed. Administration of steviol resulted in a statistically significant increase in the fractional sodium excretion (FeNa + ), fractional potassium excretion (FeK + ), urinary flow as percent of glomerular filtration rate (V/GFR) and glucose clearance (C G ) when compared to controls, but these effects were absent with the dose of 0.5 mg.kg -1 /h. The steviol clearance (C S ) was higher than the C in and lower than the C PAH at all the doses employed in this study. The data suggest that steviol is secreted by renal tubular epithelium, causing diuresis, natriuresis, kaliuresis and a fall in renal tubular reabsorption of glucose.Keywords: renal function, Stevia rebaudiana, steviol, renal excretion of glucose. O efeito do esteviol, um glicosídeo da Stevia rebaudiana, no clearance da glicose em ratos ResumoStevia rebaudiana, uma planta da América do Sul usada como adoçante natural, parece exercer efeitos benéficos para a saúde humana, incluindo ação anti-hipertensiva e anti-hiperglicêmica. No presente trabalho objetivamos avaliar a excreção renal do esteviol, uma aglicona extraída das folhas de S. rebaudiana, e elucidar a participação deste composto na excreção renal de glicose em ratos, o qual foi sugerido agir no sistema de transporte tubular renal Na + -glicose. O esteviol foi obtido por hidrólise enzimática com pectinase. Foram usados 30 ratos Wistar machos e pesando 345 g. Após um período controle, o esteviol foi infundido iv em três doses (0,5, 1,0 e 3,0 mg.kg -1 /h) de acordo com técnicas clássicas de clearance. Durante os experimentos não houve alterações significantes no clearance da inulina (C in ) e do ácido-aminohipúrico (C PAH ). A administração de esteviol resultou em um aumento estatisticamente significante na excreção fracional de sódio (FeNa + ) e potássio (FeK + ), no fluxo urinário como porcentagem da taxa de filtração glomerular (V/GFR) e do clearance de glicose (C G ) quando comparados aos animais controles, embora estes efeitos estivessem ausentes na dose de 0,5 mg.kg -1 /h. O clearance de esteviol (C...

Biotechnological approaches in Stevia rebaudiana and its Therapeutic Applications

“…Stevioside and steviol induce diuresis and natriuresis, without a significant change in glomerular filtration rate or renal plasma flow [81]. It was found that in the diabetic rats fed with Stevia on renal function observed remarkable reduction in the glomerular filtration rate (GFR) and renal plasma flow (RPF).…”

Anticariogenic properties and effects on periodontal structures of Stevia rebaudiana Bertoni. Narrative review.

“…It has been described that the hypotensor effect of stevioside is due to the inhibition of the influence of calcium from the extracelular fluid 49 . Plus, it has been shown that stevioside and steviol induce diuresis and natriuresis, without a significant change in glomerular filtration rate or renal plasma flow 50 . All this.…”

“…The evidence suggests that stevioside improves secretion and sensitivity to insulin 18 . Besides, it generates the concomitant suppression of glucagon's secretion 18 and the decline in the renal tubular reabsorption of glucose 50 .…”

Profile and Pro-Health Properties of Stevia Rebaudiana Bertoni

“…Jest białym, krystalicznym, bezwonnym proszkiem wyekstrahowanym z liści stewii, stanowiącym 6 -18 % ich świe-żej masy [9,13,18]. Zawiera trzy cząsteczki glukozy oraz stewiol [21]. Jest odpowiedzialny za gorzkawy posmak stewii.…”