Isorhoifolin

Molecules. 2013 Nov 14;18(11):14105-21.

Chemical composition and antioxidant activity of Tánara ótó (Dracocephalum palmatum Stephan), a medicinal plant used by the North-Yakutian nomads.[Pubmed: 24241154 ]

Dracocephalum palmatum Stephan (Lamiaceae) is a medicinal plant used by the North-Yakutian nomads.
METHODS AND RESULTS:
From the crude ethanolic extract of the aerial parts of this plant, 23 compounds (phenylpropanoids, coumarins, flavonoids, and triterpenes) were isolated. Among these, eight compounds (salvianolic acid B, caftaric acid, cichoric acid, umbelliferone, aesculetin, apigenin-7-O-β-D-glucuronopyranoside, Isorhoifolin, and luteolin-4'-O-β-D-glucopyranoside) were detected for the first time in the genus Dracocephalum. Their structures were elucidated based on chemical and spectral data. The levels of most of the compounds detected in the cultivated sample were close to that of the wild sample, indicating the reproducibility of the biologically active compounds of D. palmatum through cultivation.
CONCLUSIONS:
Investigation into the biological activity of D. palmatum under in vitro conditions demonstrated that its extracts have a strong antioxidant effect due to the presence of high concentrations of phenolic compounds.

J Pharm Pharmacol. 2013 Jun;65(6):928-36.

The positive inotropic effect of the ethyl acetate fraction from Erythrina velutina leaves on the mammalian myocardium: the role of adrenergic receptors.[Pubmed: 23647686 ]

We studied the effects of ethyl acetate fraction (EAcF) obtained from Erythrina velutina leaves on mammalian myocardium.
METHODS AND RESULTS:
The effect of EAcF on the contractility was studied using guinea-pig left atria mounted in a tissue bath (Tyrode's solution, 29°C, 95% CO2 , 5% O2 ) and electrically stimulated (1 Hz). Concentration-response curves of EAcF were obtained in the presence of propranolol (1 μm), nifedipine (1 μm) and in reserpinized animals (5 mg/kg). The involvement of l-type calcium current (ICa,L ) on the EAcF effect was observed in cardiomyocytes of mice assessed using patch-clamp technique. EAcF (550 μg/ml) had a positive inotropic effect, increasing the atrial force by 164% (EC50  = 157 ± 44 μg/ml, n = 6), but it was less potent than isoproterenol (EC50  = 0.0036 ± 0.0019 μg/ml, n = 8). The response evoked by EAcF was abolished by propranolol or nifedipine. Reserpine did not alter the inotropic response of EAcF. Furthermore, an enhancement of the ICa,L peak (31.2%) with EAcF was observed. Chemical analysis of EAcF revealed the presence of at least 10 different flavonoid glycoside derivatives. Two were identified as vicenin II and Isorhoifolin.
CONCLUSIONS:
We conclude that EAcF increases the cardiac contractile force by increasing the l-type calcium current and activating the adrenergic receptor pathway.

Int Angiol. 2008 Feb;27(1):81-5.

Different flavonoids present in the micronized purified flavonoid fraction (Daflon 500 mg) contribute to its anti-hyperpermeability effect in the hamster cheek pouch microcirculation.[Pubmed: 18277344]

This study evaluated microcirculatory effects of the flavonoid substances that constitute the micronized purified flavonoid fraction (MPFF) (Daflon 500 mg) in comparison to diosmin.
METHODS AND RESULTS:
In groups of 3 male hamsters, oral treatment with MPFF or diosmin (15 min before anesthesia) did not alter blood pressure. At 10 or 30 mg/kg, both MPFF and diosmin significantly decreased the leaky sites caused by ischemia/reperfusion (I/R) (30 min) in the hamster cheek pouch; the effect was significantly higher with MPFF (39+/-1% and 52+/-1%, respectively) than diosmin (18+/-1% and 37+/-3%, respectively). Eight groups of 3 hamsters each were treated with the components of MPFF. Diosmetin only decreased the number leaky sites at 30 mg/kg (decrease: 15+/-2%). The decrement at 10 and 30 mg/kg averaged at: 17+/-3% and 44+/-1%, respectively, for hesperidin; 19+/-1% and 46+/-2%, respectively, for linarin; and 30+/-1% and 44+/-1%, respectively, for Isorhoifolin. Hesperidin, linarin, and Isorhoifolin each displayed an anti-leakage effect comparable to or greater than diosmin. MPFF decreases permeability more than any of its single constituents, suggesting that the flavonoids present in its formulation have a synergistic action.
CONCLUSIONS:
These results illustrate that MPFF is more potent than single diosmin in this model of hyperpermeability and that each of the flavonoid substances present in MPFF contribute to its action.

Biomedicine & Preventive Nutrition,2011,1(4): 268-272.

Flavonoid rich fraction of Pilea microphylla (L.) attenuates metabolic abnormalities and improves pancreatic function in C57BL/KsJ-db/db mice[Reference: WebLink]

Pilea microphylla Linn. (Urticaceae) and related genera are used in Jamaican and Chinese traditional medicine for the treatment of diabetes. This study was aimed at evaluating the antidiabetic potential of flavonoid rich fraction of Pilea microphylla (PM1) and its possible mechanism of action in C57BL/KsJ-db/db mice.
METHODS AND RESULTS:
These diabetic mice were treated with PM1 (100 mg/kg, i.p.) for 21 days and were evaluated for parameters such as food efficiency ratio, oral glucose tolerance test, inhibition of plasma dipeptidyl peptidase IV (DPP-IV), metabolic markers, pancreas histology and hematological profile. PM1 significantly (P < 0.05) reduced body weight, food efficiency ratio, plasma glucose, triglycerides and inhibited plasma DPP-IV, while increasing insulin levels in C57BL/KsJ-db/db mice. PM1 also improved oral glucose tolerance significantly (P < 0.05) with mean percentage reduction of 31.2 in glucose excursion (AUC0−120 min) and preserved islet architecture of pancreas without showing any detectable hematological toxicity at administered dose. The presence of flavonoids namely quercetin (reported DPP-IV inhibitor), rutin, chlorogenic acid (reported lipid lowering property) along with others (luteolin-7-O-glucoside, apigenin-7-O-glucoside, Isorhoifolin) in PM1 reversed the disturbed metabolic milieu in C57BL/KsJ-db/db mice.
CONCLUSIONS:
The overall antidiabetic effect could be the result of the combination of several constituents acting in concert, in a holistic manner, thereby restoring the homeostasis in energy consumption and utilization.