Acute and Chronic Antihypertensive Effect of Fractions, Tiliroside and Scopoletin from Malva parviflora.

Hypertension is a disease of high prevalence and morbidity where vascular inflammation and associated oxidative stress (endothelial dysfunction) is the underlying cause of this pathology. We are reporting the antihypertensive activity of extracts and fractions of Malva parviflora in mice with chronic and acute hypertension. Also, the treatments of this plant were able to counteract the kidney inflammation and associated oxidative stress. The chronic hypertension model consisted of administration of angiotensin II (AGII) during 12 weeks, causing a sustained increase in systolic (SBP) or diastolic (DBP) pressure, with values of pharmacological constants of: ED50 = 0.038 mg/kg y Emax = 135 mmHg for SBP and ED50 = 0.046 mg/kg y Emax = 98 mmHg for DBP. The chronic hypertension caused the inflammation and lipid peroxidation in kidneys, measured by of tissue level of cytokines such as interleukin-1ß (IL-1ß), IL-6, Tumor Necrosis Factor-α (TNF-α), IL-10 and malondialdehyde, and treatments for M. parviflora were able to modulate these parameters. The chemical fractionation allowed to identify three compounds: oleanolic acid, tiliroside and scopoletin, which were tested in a model of acute hypertension. The pharmacodynamic parameters for SBP were ED50 = 0.01 and 0.12 mg/kg while Emax = 33.22 and 37.74 mmHg for scopoletin and tiliroside, respectively; whereas that for DBP data were ED50 = 0.01 and 0.02 mg/kg; with an Emax = 7.00 and 6.24 mmHg, in the same order. M. parviflora, is able to counteract the effect of chronic and acute administration of AGII, on hypertension, but also the inflammatory and oxidative damage in the kidney. The oleanolic acid, scopoletin and tiliroside are the compounds responsible for such activities.

Data of the effects of acetone fraction from Sechium edule (Jacq.) S.w. edible roots in the kidney of endothelial dysfunction induced mice.

Endothelial dysfunction induced by Angiotensin II (AG II) plays an important role in the pathogenesis of hypertension and is accompanied by a prooxidative condition, which in turn induces an inflammatory state, vascular remodeling, and tissue damage including the kidney (Schmitt and Dirsch, 2009) [1]. New drugs that can control several of these pathologies are required. Sechium edule has been reported to possess antioxidant, anti-inflammatory and antihypertensive activity (Ibarra-Alvarado et al., 2010) [2]. This paper contains data complementary to those published in Journal of Ethnopharmacology (Moreno et al., 2018) [3], evaluating the effect in kidney of hypertensive mice of the acetone fraction from S. edule to control de pro-oxidative state, reduction of the inflammatory adhesion molecule (ICAM) and recruitment of inflammatory cells.

Acetone fraction from Sechium edule (Jacq.) S.w. edible roots exhibits anti-endothelial dysfunction activity.

ETHNOPHARMACOLOGICAL RELEVANCE: A recent ethnomedical survey on medicinal plants grown in Mexico revealed that Sechium edule (Jacq.) Sw. (Cucurbitaceae) is one of the most valued plant species to treat cardiovascular diseases, including hypertension. Fruits, young leaves, buds, stems, and tuberous roots of the plant are edible. Considering that endothelial dysfunction induced by Angiotensin II plays an important role in the pathogenesis of hypertension and is accompanied by a prooxidative condition, which in turn induces an inflammatory state, vascular remodeling, and tissue damage, and that S. edule has been reported to possess antioxidant, anti-inflammatory and antihypertensive activity, its capability to control endothelial dysfunction was also assessed. AIM OF THE STUDY: To assess in vivo the anti-endothelial dysfunction activity of the acetone fraction (rSe-ACE) of the hydroalcoholic extract from S. edule roots. MATERIALS AND METHODS: Endothelial dysfunction was induced in female C57BL/6 J mice by a daily intraperitoneal injection of angiotensin II for 10 weeks. Either rSe-ACE or losartan (as a control) were co-administered with angiotensin II for the same period. Blood pressure was measured at weeks 0, 5, and 10. Kidney extracts were prepared to determine IL1ß, IL4, IL6, IL10, IL17, IFNγ, TNFα, and TGFß levels by ELISA, along with the prooxidative status as assessed by the activity of antioxidant enzymes. The expression of ICAM-1 was evaluated by immunohistochemistry in kidney histological sections. Kidney and hepatic damage, as well as vascular tissue remodeling, were studied. RESULTS: The rSe-ACE fraction administered at a dose of 10 mg/kg was able to control hypertension, as well as the prooxidative and proinflammatory status in kidney as efficiently as losartan, returning mice to normotensive levels. Additionally, the fraction was more efficient than losartan to prevent liver and kidney damage. Phytochemical characterization identified cinnamic acid as a major compound, and linoleic, palmitic, and myristic acids as the most abundant non-polar components in the mixture, previously reported to aid in the control of hypertension, inflammation, and oxidative stress, three important components of endothelial dysfunction. IN CONCLUSION: this study demonstrated that rSe-ACE has anti-endothelial dysfunction activity in an experimental model and highlights the role of cinnamic acid and fatty acids in the observed effects.

Pharmacokinetic Study of Biotransformation Products from an Anxiolytic Fraction of Tilia americana.

An anxiolytic fraction of Tilia americana standardized in tiliroside, rutin, quercitrin, quercetin glucoside, and kaempferol was obtained. After oral administration of the fraction, the above-mentioned flavonoids were not detected in plasma over 24 h. However, meta and para hydroxyphenylacetic acid and dihydroxyphenylacetic acid (m-HPAA, p-HPAA and DOPAC) were monitored. These are the biotransformation compounds of the aglycones of kaempferol and quercetin; these aglycones are products of the other flavonoids present in the anxiolytic fraction. The analytical methods (HPLC) for flavonoids and the related compounds (m-HPAA, p-HPAA and DOPAC) were validated, determining the parameters of accuracy, precision, specificity or selectivity, limit of detection, quantification range, and robustness. The pharmacokinetic assay was performed with ICR mice strains, which were given 200 mg/kg of the standardized active fraction. The results of validation of the analytical methods were obtained, allowing it to be established in a validated way that no flavonoids present in the anxiolytic fraction of T. americana were detected in plasma. However, detection and follow up was possible for the serum levels of m-HPAA, p-HPAA, and DOPAC. The three compounds follow a two-compartment model with very similar parameters between m-HPAA and p-HPAA, some being different from the ones characterized in the pharmacokinetics of DOPAC.

Extracts and Fractions from Edible Roots of Sechium edule (Jacq.) Sw. with Antihypertensive Activity.

Sechium edule is traditionally used in Mexico as a therapeutic resource against renal diseases and to control high blood pressure. The purpose of this work is to evaluate the antihypertensive effect of the hydroalcoholic extract obtained from the roots of this plant, including its fractions and subfractions, on different hypertension models induced with angiotensin II (AG II). The hydroalcoholic extract was tested on an in vitro study of isolated aorta rings denuded of endothelial cells, using AG II as the agonist; this assay proved the vasorelaxant effect of this extract. Vagotomized rats were administered different doses of AG II as well as the Hydroalcoholic extract, which reduced blood pressure in 30 mmHg approximately; subsequently this extract was separated into two fractions (acetone and methanol) which were evaluated in the acute hypertension mouse model induced with AG II, where the acetone fraction was identified as the most effective one and was subsequently subfractioned using an open chromatographic column packed with silica gel. The subfractions were also evaluated in the acute hypertension model. Finally, the extract, fraction, and active subfraction were analyzed by MS-PDA-HPLC, identifying cinnamic derivative compounds like cinnamic acid methyl ester.