Effects of alismol isolated from Alismatis Rhizoma on calcium-induced contraction in the rabbit thoracic aorta

Pharmacological Activities of Alisma orientale against Nonalcoholic Fatty Liver Disease and Metabolic Syndrome: Literature Review

Nonalcoholic fatty liver disease (NAFLD) is a rapidly emerging hepatic manifestation of metabolic syndrome. However, its unrevealed mechanism and complicated comorbidities have led to no specific medication, except for weight loss and lifestyle modification. Alisma orientale (Sam.) Juzep (A. orientale, Alismataceae) has been increasingly reported on therapeutic effects of A. orientale against NAFLD and metabolic syndrome such as insulin resistance, hyperlipidemia, and obesity. Therefore, this study aimed to review the preclinical efficacy of A. orientale and its chemical constituents including Alisol A 24-acetate, Alisol B 23-acetate, Alisol F, and Alismol against NAFLD and metabolic syndrome. A. orientale prevented hepatic triglyceride accumulation through suppressing de novo lipogenesis and increasing lipid export. In addition, it controlled oxidative stress markers, lipoapoptosis, liver injury panels, and inflammatory and fibrotic mediators, eventually influencing steatohepatitis and liver fibrosis. Moreover, it exhibited pharmacological activities against hyperlipidemia, obesity, and hyperglycemia as well as appetite. These biological actions of A. orientale might contribute to adiponectin activation or a role as a farnesoid X receptor agonist. In particular, Alisol A 24-acetate and Alisol B 23-acetate could be expected as main compounds. Taken together, A. orientale might be an effective candidate agent for the treatment of NAFLD and its comorbidities, although further assessment of its standardization, safety test, and clinical trials is consistently required.

Chemical Composition and Characteristic Odor Compounds in Essential Oil from Alismatis Rhizoma (Tubers of Alisma orientale)

Chemical composition and potent odorants that contribute to the characteristic odor of essential oil from Alismatis Rhizoma (tubers of Alisma orientale) were investigated by gas chromatography-mass spectrometry (GC-MS), GC-olfactometry (GC-O), aroma extract dilution analysis (AEDA) and relative flavor activity (RFA) methods. Fifty components, representing 94.5% of the total oil, were identified. In this study, we newly identified thirty-nine compounds in the oil from tubers of A. orientale. The major constituents of the essential oil were khusinol (36.2%), δ-elemene (12.4%), germacron (4.1%), alismol (3.8%), β-elemene (3.1%), and α-bisabolol (1.9%). Through sensory analysis, sixteen aroma-active compounds were detected and the key contributing aroma-active compounds were δ-elemene (woody, flavor dilution (FD)-factor = 4, RFA = 0.3) β-elemene (spicy, FD = 5, RFA = 0.7), spathulenol (green, FD = 5, RFA = 1.0), γ-eudesmol (woody, FD = 6, RFA = 1.5), and γ-cadinol (woody, FD = 5, RFA = 1.0). These compounds are thought to contribute to the odor from tubers of A. orientale. These results imply that the essential oil from the tubers of A. orientale deserve further investigations in the phytochemical and medicinal fields.

Protective Effects of Alisma orientale Extract against Hepatic Steatosis via Inhibition of Endoplasmic Reticulum Stress

Endoplasmic reticulum (ER) stress is associated with the pathogenesis of hepatic steatosis. Alisma orientale Juzepzuk is a traditional medicinal herb for diuretics, diabetes, hepatitis, and inflammation. In this study, we investigated the protective effects of methanol extract of the tuber of Alisma orientale (MEAO) against ER stress-induced hepatic steatosis in vitro and in vivo. MEAO inhibited the tunicamycin-induced increase in luciferase activity of ER stress-reporter constructs containing ER stress response element and ATF6 response element. MEAO significantly inhibited tunicamycin-induced ER stress marker expression including GRP78, CHOP, and XBP-1 in tunicamycin-treated Human hepatocellular carcinoma (HepG2) cells and the livers of tunicamycin-injected mice. It also inhibited tunicamycin-induced accumulation of cellular triglyceride. Similar observations were made under physiological ER stress conditions such as in palmitate (PA)-treated HepG2 cells and the livers of high-fat diet (HFD)-induced obese mice. MEAO repressed hepatic lipogenic gene expression in PA-treated HepG2 cells and the livers of HFD obese mice. Furthermore, MEAO repressed very low-density lipoprotein receptor (VLDLR) expression and improved ApoB secretion in the livers of tunicamycin-injected mice or HFD obese mice as well as in tunicamycin or PA-treated HepG2 cells. Alismol, a guaiane-type sesquiterpenes in Alisma orientale, inhibited GRP78 expression in tunicamycin-treated HepG2 cells. In conclusion, MEAO attenuates ER stress and prevents hepatic steatosis pathogenesis via inhibition of expression of the hepatic lipogenic genes and VLDLR, and enhancement of ApoB secretion.

Protostane Triterpenoids from the Rhizome of Alisma orientale Exhibit Inhibitory Effects on Human Carboxylesterase 2

Twelve new and 10 known protostane triterpenoids were isolated from the rhizome of Alisma orientale. Their structures were elucidated based on physical data analyses, including UV, HRESIMS, NMR experiments ((1)H, (13)C NMR, (1)H-(1)H COSY, HSQC, HMBC, and NOESY), and induced electronic circular dichroism. New compounds 1-12 were classified as protostanes (1-10), 29-norprotostane (11), and 24-norprotostane (12) by structure analyses. Furthermore, the inhibitory effects on human carboxylesterases (hCE-1, hCE-2) of compounds 1-22 were evaluated. Compounds 2, 6, 9, and 11 showed moderate inhibitory activities and were selective toward hCE-2 enzymes, with IC50 values of 8.68, 4.72, 4.58, and 2.02 μM, respectively. The inhibition kinetics of compound 11 toward hCE-2 were established, and the Ki value was determined as 1.76 μM using a mixed inhibition model. The interaction of bioactive compound 11 with hCE-2 was shown using molecular docking.

Prescription pattern of Chinese herbal products for hypertension in Taiwan: a population-based study

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine (TCM) has been commonly used in Asia country. The aim of this study is to analyze the utilization of TCM among hypertensive patients in Taiwan.

MATERIALS AND METHODS

The use of TCM for primary hypertensive patients was evaluated using a randomly sampled cohort of 1,000,0s recruited from the National Health Insurance Research Database in 5-year period from 2006 to 2010.

RESULTS

Overall, 49.7% (n=42,586) of primary hypertension utilized TCM and 12.1% (n=5132) of them used TCM for the treatment of hypertension. Among the top 10 most frequently prescribed herbal formulae, Tian-Ma-Gou-Teng-Yin, Gout-Teng-San, Liu-Wei-Di-Huang-Wang and its derivatives were found to be the most common herbal formulae prescribed by TCM doctors for the treatment of hypertension in Taiwan.

CONCLUSION

This study showed the utilization pattern of Chinese herbal product in patients with hypertension. Further researches and clinical trials are needed to evaluate the efficacy of these Chinese formulae or its ingredients in treating hypertension.

Cytotoxic, cytostatic and HIV-1 PR inhibitory activities of the soft coral Litophyton arboreum

Bioassay-guided fractionation using different chromatographic and spectroscopic techniques in the analysis of the Red Sea soft coral Litophyton arboreum led to the isolation of nine compounds; sarcophytol M (1), alismol (2), 24-methylcholesta-5,24(28)-diene-3β-ol (3), 10-O-methyl alismoxide (4), alismoxide (5), (S)-chimyl alcohol (6), 7β-acetoxy-24-methylcholesta-5-24(28)-diene-3,19-diol (7), erythro-N-dodecanoyl-docosasphinga-(4E,8E)-dienine (8), and 24-methylcholesta-5,24(28)-diene-3β,7β,19-triol (9). Some of the isolated compounds demonstrated potent cytotoxic- and/or cytostatic activity against HeLa and U937 cancer cell lines and inhibitory activity against HIV-1 protease (PR). Compound 7 was strongly cytotoxic against HeLa cells (CC₅₀ 4.3 ± 0.75 µM), with selectivity index of SI 8.1, which was confirmed by real time cell electronic sensing (RT-CES). Compounds 2, 7, and 8 showed strong inhibitory activity against HIV-1 PR at IC₅₀s of 7.20 ± 0.7, 4.85 ± 0.18, and 4.80 ± 0.92 µM respectively. In silico docking of most compounds presented comparable scores to that of acetyl pepstatin, a known HIV-1 PR inhibitor. Interestingly, compound 8 showed potent HIV-1 PR inhibitory activity in the absence of cytotoxicity against the cell lines used. In addition, compounds 2 and 5 demonstrated cytostatic action in HeLa cells, revealing potential use in virostatic cocktails. Taken together, data presented here suggest Litophyton arboreum to contain promising compounds for further investigation against the diseases mentioned.

Pharmacological mechanisms involved in the vasodilator effects of extracts from Echinodorus grandiflorus

We investigated the vascular effects of a crude aqueous extract (AEEG) of Echinodorus grandiflorus (Alismataceae) using the in vitro experimental models of the rabbit isolated aorta and perfused kidney. Echinodorus grandiflorus, a native semi-aquatic plant widely distributed in Brazil, has been extensively used in Brazilian folk medicine for the treatment of high blood pressure and inflammatory diseases. The bolus injection of AEEG (0.1-10 mg) into the rabbit renal circulation pre-contracted with norepinephrine induced marked and dose-dependent vasodilator responses (maximum of 37+/-4%; n=6; P<0.001), which was similar to that induced by injection of 10 mmol acetylcholine (41+/-3%). Moreover, AEEG elicited a significant and concentration-dependent relaxation in the endothelium-intact, but not endothelium-denuded aortic rings, reaching the maximum of 81+/-5% (n=7, P<0.001). Inhibition of the nitric oxide-cGMP pathway with L-NAME (100 microM) or Methylene Blue (20 microM) reduced maximum relaxation induced by AEEG from 81+/-5% to 46+/-3 and 45+/-3%, respectively (n=7, P<0.001). A similar reduction was obtained with the incubation of the aortic rings with the selective PAF receptor antagonist WEB 2086 (10 microM) (from 81+/-5% to 55+/-3%; n=7; P<0.01). Conversely, blockade of muscarinic receptors with atropine (10 microM) did not affect the vasodilator effects of AEEG, while inhibition of the enzyme cyclooxigenase not only did not block, but rather potentiated vasodilation induced by AEEG (n=7, P<0.001). Finally, blockade of Ca(2+)- and ATP-activated K(+) channels using the specific blockers charydbotoxin (100 nM) and glibenclamide (3 microM), respectively, did not modify aortic relaxation induced by AEEG. We conclude that water-soluble extracts from leaves of Echinodorus grandiflorus elicit an endothelium-dependent, nitric oxide and PAF receptor-mediated vasodilation in rabbit aortic rings, which does not appear to involve the generation of vasodilating prostaglandins or the activation of K(+) channels. This potent vasodilator effect of the extracts was confirmed in the isolated rabbit renal circulation.

Effects of sesquiterpenes and triterpenes from the rhizome of Alisma orientale on nitric oxide production in lipopolysaccharide-activated macrophages: absolute stereostructures of alismaketones-B 23-acetate and -C 23-acetate

The methanolic extract from a Chinese herbal medicine, the rhizome of Alisma orientale, was found to exhibit inhibitory activity of nitric oxide (NO) production in lipopolysaccharide (LPS)activated macrophages. Novel triterpenes, alismaketones-B 23-acetate and -C 23-acetate, were isolated from the active extract together with eight sesquiterpenes and eighteen protostane-type triterpenes. The absolute stereostructures of new triterpenes were characterized on the basis of chemical and physicochemical evidence, which included the chemical correlations with known triterpenes. The guaiane-type sesquiterpenes (alismol, orientalols A and C) and protostane- and seco-protostane-types triterpenes (alisols C monoacetate, E-23-acetate, F, H, I, L-23-acetate, and M-23-acetate, alismaketones-B 23-acetate and -C 23-acetate, alismalactone 23-acetate, and 3-methylalismalactone 23-acetate) inhibited LPS-induced NO production (IC50 = 8.4-68 microM). Other triterpenes (alisols A, A monoacetate, B, B monoacetate, E, G, K-23-acetate, and N-23-acetate and 11-deoxyalisol B) also showed the potent inhibitory activity, but they showed cytotoxic effects more than 30 microM (MTT assay). In addition, alismol and alisol F were found to suppress iNOS induction.

Pharmacology of Casimiroa edulis; III. Relaxant and contractile effects in rat aortic rings

The relaxant and contractile effects of an aqueous extract of the seeds of the hypotensive plant Casimiroa edulis were investigated in rat aortic rings. The extract inhibited contractions elicited by noradrenaline, serotonin and prostaglandin F2 alpha, but did not affect responses to KCl. Inhibition did not require the presence of intact vascular endothelium and was not affected by histamine antagonists. In this preparation, the extract also elicited concentration-related contractions which were more marked in the absence of endothelium, were not blocked by histamine antagonists, and were completely suppressed by alpha-adrenergic blockade. It was concluded that the relaxant effect of the extract is not exerted through release of an endothelial relaxing factor nor through blockade of calcium channels or of specific smooth muscle receptors, and does not involve histaminergic mechanisms. The contractile effect is modulated by vascular endothelium and is alpha-adrenergic in nature.

Calcium antagonistic properties of the sesquiterpene T-cadinol and related substances: structure-activity studies

The calcium antagonistic properties of (+)-T-cadinol, some of its stereoisomers and related terpenes were investigated in both functional and radioligand binding studies, and the effects were compared with those of the dihydropyridine calcium antagonist (+/-)-nimodipine. In the isolated rat aorta, the terpenes relaxed contractions induced by 60 mM K+ more potently than those induced by phenylephrine. (+)-T-cadinol and its stereoisomers were the most potent among the terpenes to relax K(+)-induced contractions, whereas they were approximately 10,000 times less potent than (+/-)-nimodipine in this regard. Binding of the dihydropyridine radioligand [3H]-(+)-PN200-110 was studied on rat cerebral cortical membranes. Displacement and saturation studies indicated that (+)-T-cadinol caused a competitive inhibition of binding. The log Ki values for (+)-T-cadinol and (+/-)-nimodipine from displacement studies (-4.7 and -9.2) corresponded with the log RC50 values for relaxation of K(+)-contracted rat aortas (-5.0 and -9.0). For the terpenes, there was a significant correlation (P < 0.001, rs = 0.89) between displacement of dihydropyridine binding and the ability to relax K(+)-induced contractions. The structures of three terpenes were chemically modified by blocking hydroxyl groups. The potency of these derivatives, as well as the naturally occurring derivative-2-oxo-T-cadinol, to relax K(+)-induced contractions was not correlated to the lipophilicity of the compounds. Instead, other qualities appear to be of importance for the functional effects.(ABSTRACT TRUNCATED AT 250 WORDS)