Guaiane-Type Sesquiterpenoids from Alismatis Rhizoma and Their Anti-inflammatory Activity

Abstract

Twelve guaiane-type sesquiterpenoids, including four new ones, 10-O-methyl-orientalol A (1), 10-Oethyl-alismoxide (2), 3β,4β-expoxy-chrysothol (3), orientalol G (4), and a new norsesquiterpenoid, orientalol H (5), were isolated from Chinese Alismatis Rhizoma, the dried rhizome of Alisma orientale. The structures of new compounds were elucidated on the basis of spectroscopic data. Moreover, the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells of all compounds was tested.Key words Alismatis Rhizoma; Alisma orientale; guaiane-type sesquiterpenoid; anti-inflammatory Alismatis Rhizoma ("Zexie" in Chinese), a Chinese crude drug prepared from dried rhizome of the aquatic plant Alisma orientale (SAM.) JUZEP. (Alismataceae) widely cultivated in China and Japan, has been used as a diuretic agent used to "remove dampness and promote water metabolism" in the body according to Chinese medicinal principles.1-5) Previous phytochemical and pharmacological study on Alismatis Rhizoma reported the isolation of prostane-type triterpenes and guaiane-type sesquiterpenes, which exhibited a series of bioactivities, such as diuretic, anti-hepatitis B virus (HBV), antibacterial, anti-hypertentive, hypolipidemic, anti-inflammatory, positive hypocholesterolemic activity, and repairing action to cholinergic acetyltransferase, etc.1-3,6-10) With the aim of discovering more structurally unique and bioactive terpenoids from natural resource, five new guaiane-type sesquiterpenes (1-5) along with seven known ones (6-12) (Fig. 1) were isolated from Alismatis Rhizoma. Furthermore, all compounds were examined for their anti-inflammatory potential and compounds 6 and 12 showed moderate inhibition of nitric oxide (NO) production with IC 50 values of 36.997 and 48.602 µM, respectively. Herein, we report the isolation, structural elucidation and biological evaluation of the isolated compounds. Results and DiscussionThe powdered Alismatis Rhizoma was extracted with 95% EtOH, and the concentrated extract was suspended in H 2 O followed by partition with EtOAc. The EtOAc fraction was purified using various column chromatographies to yield twelve guaiane-type sesquiterpenoids (1-12).Compound 1, colorless oil, gave rise to a quasi-molecular ion peak at m/z 291.1935 ([M+Na] + ) in the positive high resolution-electrospray ionization (HR-ESI)-MS, which corresponded to the molecular formula C 16 H 28 O 3 , in combination with its 13 C-NMR and distortionless enhancement by polarization transfer (DEPT) analysis. The IR spectrum exhibited a broad absorption at 3420 cm −1 due to hydroxyl group. The 1 H-NMR spectrum (Table 1) showed the presence of a tertiary methyl [δ H 1.09 (3H, s)], a hydroxymethyl [δ H 3.80 (1H, dd,

Alisol A attenuates high‐fat‐diet‐induced obesity and metabolic disorders via the AMPK/ACC/SREBP‐1c pathway

“…Obesity has been proven to be accompanied by inflammation in organs such as the liver and skeletal muscle, consequently promoting metabolic dysfunction and insulin resistance. 37,38 Considering that alisol A has been shown to have antiinflammatory 20 properties, our results also suggested that it could alleviated inflammation in adipose tissue of DIO mice, we supposed that the metabolic improvement effects of alisol A may be partially due to it's suppression of inflammatory damage.…”

“…Modern medical researches about this herb found active ingredients in it and numerous studies have shown that Rhizoma Alismatis extract has various biological activities, such as hypolipemic, antidiabetic, anti‐urinary stone, anti‐inflammation and anti‐tumour activities. Li S et al found that Rhizoma Alismatis extract can significantly reduce the serum LDL levels of ApoE‐/‐ mice and promote the removal of chylomicron in the liver .…”

Diuretic Activity of Compatible Triterpene Components of Alismatis rhizoma

“…Juzepzuk (Alismataceae), is a natural medicine widely cultivated in China, Japan, Korea, India, and Europe. Traditionally, AR is known to exhibit diuretic, hyperlipidemic, inflammatory, antitumoral, and damp-heat clearing actions [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ] and has been used for treating dysuria, edema, urinary tract infection, retention of fluid and phlegm, and vertigo for more than 1000 years [ 8 ]. As a folk medicine that has long been used to promote health and longevity, AR is now included in the Pharmacopoeia of China as a representative traditional Chinese herbal diuretic.…”

Guaiane-Type Sesquiterpenoids From Dendranthema morifolium (Ramat.) S. Kitam Flowers Protect H9c2 Cardiomyocyte From LPS-Induced Injury

“…S. Kitam flowers. And pharmacological investigations showed that this kind of compounds exhibited mainly cytotoxicity and anti-inflammatory activities [15][16][17] ; however, there has been no research about the mechanism. We investigated the protective effects of guaianetype sesquiterpenoids on LPS-induced injury in H9c2 cardiomyocyte in order to find the mechanism and the effective drugs to protect cardiomyocyte injury in our study.…”