Novel megastigmanes with lipid accumulation inhibitory and lipid metabolism-promoting activities in HepG2 cells from Sedum sarmentosum

Alkylphthalides with intracellular triglyceride metabolism-promoting activity from the rhizomes of Cnidium officinale Makino

Methanol extract of the Cnidium officinale Makino rhizome, which is used as a crude drug Cnidium Rhizome (Cnidii Rhizoma; "Senkyu" in Japanese) and is listed in the Japanese Pharmacopoeia XVIII, showed intracellular triglyceride metabolism-promoting activity in high glucose-pretreated HepG2 cells. Thirty-five constituents, including two new alkylphthalide glycosides, senkyunosides A (1) and B (2), and a neolignan with a new stereoisomeric structure (3), were isolated in the extract. Their stereostructures were elucidated based on chemical and spectroscopic evidence. Among the isolates, several alkylphthalides, (Z)-3-butylidene-7-methoxyphthalide (9) and senkyunolides G (10), H (14), and I (15), and a polyacetylene falcarindiol (26), were found to show significant activity without any cytotoxicity at 10 μM.

Ameliorative effect of bofutsushosan (Fangfengtongshengsan) extract on the progression of aging-induced obesity

This study aimed to compare fat accumulation in young and aged mice raised on a high-fat diet and to characterize the obesity-reducing effects of a Kampo medicine, bofutsushosan (BTS; fangfengtongshengsan in Chinese). Aged mice fed a high-fat diet containing 2% BTS extract for 28 days exhibited a significant reduction in weight gain and accumulation of visceral and subcutaneous fat, which were greater degree of reduction than those of the young mice. When the treatment period was extended to two months, the serum aspartate aminotransferase and alanine aminotransferase levels and the accumulation of fat droplets in the hepatocytes decreased. The mRNA expression of mitochondrial uncoupling protein 1 (UCP1) in the brown adipose tissue was significantly reduced in the aged mice compared to the young mice but increased by 2% in the BTS-treated aged mice. Additionally, the effect of BTS extract on oleic acid-albumin-induced triglyceride accumulation in hepatoblastoma-derived HepG2 cells was significantly inhibited in a concentration-dependent manner. Evaluation of the single crude drug extracts revealed that Forsythia Fruit, Schizonepeta Spike, and Rhubarb were the active components in BTS extract. These results suggest that BTS extract is effective against visceral, subcutaneous, and ectopic fats in the liver, which tend to accumulate with aging. Thus, BTS extract is useful in preventing and ameliorating the development of obesity and metabolic syndrome.

Pharmaceutical Food Science: Search for Bio-Functional Molecules Obtained from Natural Resources to Prevent and Ameliorate Lifestyle Diseases

In this review, our resent pharmaceutical food science research for bio-functional molecules obtained from natural resources that contribute to i) suppression of postprandial blood glucose elevation and/or improvement of glucose tolerance and ii) reduction of visceral fat accumulation and improvement of lipid metabolism were summarized. Based on studies using MONOTORI science, salacinol (1), neokotalanol (4), and trans-tiliroside (20) have been approved or notified by the Consumer Affairs Agency in Japan as functional substances in food with health claims, Food for Specified Health Use and Food with Functional Claims.

Megastigmane sesquiterpenoids from whole plants of Viola kunawurensis

Investigation on the chemical constituents of Viola kunawurensis resulted in the isolation of seven undescribed megastigmane sesquiterpenoids including four bicyclic megastigmane glucosides, kunawuronoside A-D, two megastigmane glucosides, kunawuronoside E-F, and a megastigmane, kunawurone A, together with ten known megastigmane sesquiterpenoids. Their structures were established by comprehensive 1D, 2D-NMR and HRESIMS analyses, and their absolute configurations were determined by comparing their calculated ECD data with the experimental ones. Evaluations of the anti-inflammatory activity revealed that kunawuronoside A-D and compounds 14-15 inhibited COX-2 expression with inhibition rates ranging from 36.7% to 58.5%, while the NO production induced by lipopolysaccharide (LPS) was suppressed by the kunawuronoside A-D in a dose-dependent manner in RAW264.7 macrophage cell line.

The Chemical Constituents of Diaphragma Juglandis Fructus and Their Inhibitory Effect on α-Glucosidase Activity

In our current investigation, 37 constituents (1-37), including 11 megastigmanes (1-11), 17 flavonoids (12-28) and 9 phenylpropanoids (29-37), were isolated from a 70%-EtOH extract of Diaphragma juglandis Fructus. Among them, compounds 1-3, 12 and 29 were new compounds and their structures were elucidated on the basis of physicochemical evidence and meticulous spectroscopic analysis (NMR, HRESIMS and CD). Compounds 13, 16, 21 and 28 showed moderate inhibitory effect on α-glycosidase inhibitory activities, with IC₅₀ values being in the range of 29.47-54.82 µM and stronger than the positive control (acarbose, 60.01 ± 4.82 µM).

Ursane-type triterpene oligoglycosides with anti-hepatosteatosis and anti-hyperlipidemic activity from the leaves of Ilex paraguariensis A. St.-Hil

The methanol extract from the leaves of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae), popularly known as mate, maté, or yerba maté, inhibits the intracellular triglyceride accumulation in HepG2 cells and suppresses the plasma triglyceride elevation in olive oil-treated mice. Three new triterpene saponins, termed mateosides I (1), II (2), and III (3), were isolated from the extract along with 29 known compounds. The structures of 1-3 were elucidated based on chemical and spectroscopic evidence. Among the isolates, principal saponin constituents, 2 and matesaponins 1 (7) and 2 (9), potently inhibited the triglyceride accumulation in HepG2 cells simultaneously treated with oleic acid and high glucose. In vivo assay of the methanol extract of I. paraguariensis revealed that 7 and 9 showed anti-hyperlipidemic activities in olive oil-treated mice. These results suggested that the saponin constituents of I. paraguariensis could be valuable bioactive marker for the anti-obesogenic activity.

Chemical constituents and absolute configuration of megastigmanes' isolated from Sedum sarmentosum Bunge

Phytochemical investigation of a methanolic extract of Sedum sarmentosum collected from Vietnam resulted in the isolation of a new megastigmane glucoside, named sedumoside K (1), together with 17 previously reported compounds (2-18). Structural elucidation of the new compound was achieved by HRFABMS, NMR spectroscopic analysis, acid hydrolysis and quantum ECD calculations. The absolute configuration of compounds 2-6 has been revised. The major isolates were tested for cytotoxic activity against HeLa human cervical cancer cells, and all showed moderate activities.

Glucose Tolerance-Improving Activity of Helichrysoside in Mice and Its Structural Requirements for Promoting Glucose and Lipid Metabolism

An acylated flavonol glycoside, helichrysoside, at a dose of 10 mg/kg/day per os for 14 days, improved the glucose tolerance in mice without affecting the food intake, visceral fat weight, liver weight, and other plasma parameters. In this study, using hepatoblastoma-derived HepG2 cells, helichrysoside, trans-tiliroside, and kaempferol 3-O-β-d-glucopyranoside enhanced glucose consumption from the medium, but their aglycones and p-coumaric acid did not show this activity. In addition, several acylated flavonol glycosides were synthesized to clarify the structural requirements for lipid metabolism using HepG2 cells. The results showed that helichrysoside and related analogs significantly inhibited triglyceride (TG) accumulation in these cells. The inhibition by helichrysoside was more potent than that by other acylated flavonol glycosides, related flavonol glycosides, and organic acids. As for the TG metabolism-promoting activity in high glucose-pretreated HepG2 cells, helichrysoside, related analogs, and their aglycones were found to significantly reduce the TG contents in HepG2 cells. However, the desacyl flavonol glycosides and organic acids derived from the acyl groups did not exhibit an inhibitory impact on the TG contents in HepG2 cells. These results suggest that the existence of the acyl moiety at the 6′′ position in the D-glucopyranosyl part is essential for glucose and lipid metabolism-promoting activities.

The hepatoprotective effects of Sedum sarmentosum extract and its isolated major constituent through Nrf2 activation and NF-κB inhibition

BACKGROUND

Sedum sarmentosum, which is recorded in Chinese Pharmacopoeia, has been applied clinically to treat liver and gallbladder diseases.

PURPOSE

This study aimed to explore the hepatoprotective effect of S. sarmentosum less polar extract (SSE) against ANIT-induced liver injury in rats, and the protective activity and mechanism of one major constituent isolated from this extract on D-GalN-induced human hepatic QSG7701 cell damage.

METHODS

Rats were divided into groups and then administrated intragastrically with SSE at doses of 100, 200 and 400 mg/kg for 7 days. They were modeled in the experiments with ANIT (70 mg/kg) to induce liver injury after the sixth day administration. The levels of serum biochemical markers ALT, AST, ALP, GGT/γ-GT, DBiL, TBiL, ALB, TP, and bile flow rate, as well as the histopathology of the liver tissue were used as indices of liver damage and measured. The inflammatory response and oxidative stress were thought to be key contributors to ANIT-induced liver injury in rats. Therefore, the inflammatory mediators (TNF-α, IFN-γ, IL-4) and oxidative stress (ROS, SOD, GSH-PX) were measured in the serum and liver homogenates, respectively. Next, phytochemical research was performed to produce the main component, and the isolated compound was evaluated for its hepatoprotective activity against QSG7701 cell injured by D-GalN through the measurement of cell viabilities, ALT, AST, IL-1β, TNF-α, IL-6, ROS, GSH-PX and SOD productions. Furthermore, the protein expression of the Nrf2 and NF-κB pathways were analyzed by western blotting.

RESULTS

SSE had an obvious effect on the decreases of ALT, AST, ALP, GGT/γ-GT, DBiL and TBiL levels, the increases of ALB and TP levels in serum, and the ANIT-induced deceleration in bile flow for liver injury. Meanwhile, SSE pretreatment alleviated ANIT-induced liver pathological injuries exhibited by HE stain of the liver. Moreover, SSE significantly suppressed levels of pro-inflammatory cytokines TNF-α and IFN-γ, and elevated level of anti-inflammatory cytokine IL-4 in serum. SSE also attenuated oxidative stress by reducing ROS level and by enhancing antioxidative enzymes (SOD and GSH-PX) activities after ANIT administration in liver tissue. Further, the major compound shown in HPLC was isolated from SSE. Its structure was identified by the spectroscopic data analysis and comparison with literature values. The principal constituent had potent protective effect on D-GalN-induced QSG7701 cells damage in a dose dependent manner with survival rates of 58.2% and 69.5% at 10 μM and 20 μM, respectively. Its cytoprotective effect was associated with the reduction of ALT, AST, IL-1β, TNF-α, IL-6 and ROS levels, and the elevation of GSH-PX and SOD productions in QSG7701 cells induced by D-GalN. Western blotting showed that this compound enhanced the expression of Nrf2, HO1, NQO1 and GCLC, and inhibited D-GalN-induced IκBα and NF-κB p65 phosphorylation.

CONCLUSIONS

Current study showed that SSE treatment exerted a protective effect on ANIT-induced liver injury. The main compound δ-amyrone isolated from the extract was characterized as the effective component with hepatoprotective activity by promoting Nrf2 antioxidant defense and suppressing NF-κB inflammatory response.

Quantitative Determination of Principal Alkaloid and Flavonoid Constituents in Wintersweet, the Flower Buds of Chimonanthus praecox

A quantitative analytical method has been developed for four alkaloids (1–4), identified as constituents responsible for the melanogenesis inhibitory activity of the extracts of wintersweet, the flower buds of Chimonanthus praecox (L.) Link (Calycanthaceae). Concurrently, a quantitative analytical protocol has been developed for five flavonoids (5–9), which also exhibited inhibitory activity. To approve the validity of the developed protocols, five extracts of the flower buds collected in Chinese market were evaluated. The optimum conditions of separation and detection of these alkaloids (1–4) and flavonoids (5–9) were achieved on a common ODS column using a MeOH-H2O mobile phase with different additives [Et2NH for alkaloids (1–4); acetic acid for flavonoids (5–9)]. The results indicated that these assays were reproducible and precise, and could be readily utilized for evaluation of the melanogenesis inhibitory activity of wintersweet on the basis of the content of the functional species. The principal flavonoid constituents (5–9) also exhibited lipid accumulation inhibitory activity.

Glycosylated porphyra-334 and palythine-threonine from the terrestrial cyanobacterium Nostoc commune

Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc commune (N. commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. commune. The glycosylation of porphyra-334 and palythine-threonine in N. commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments.

Short synthesis of the common trisaccharide core of kankanose and kankanoside isolated from Cistanche tubulosa

A short synthetic approach was developed for the synthesis of a common trisaccharide core found in kankanose, kankanoside F, H₁, H₂, and I isolated from the medicinally active plant Cistanche tubulosa. All glycosylations were carried out under nonmetallic reaction conditions. Yields were very good in all intermediate steps.

Bioactive constituents from chinese natural medicines. XXXVI. Four new acylated phenylethanoid oligoglycosides, kankanosides J1, J2, K1, and K2, from stems of Cistanche tubulosa

Four new acylated phenylethanoid oligoglycosides, kankanosides J(1) (1), J(2) (2), K(1) (3), and K(2) (4), were isolated from stems of Cistanche tubulosa (Orobanchaceae) together with isocampneoside I (5). Their structures were elucidated on the basis of chemical and physicochemical evidence. Among them, 3-5 were found to inhibit D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes.

Absolute stereostructures of olibanumols A, B, C, H, I, and J from olibanum, gum-resin of Boswellia carterii, and inhibitors of nitric oxide production in lipopolysaccharide-activated mouse peritoneal macrophages

Three new monoterpenes, olibanumols A (1), B (2), and C (3), and three new triterpenes, olibanumols H (4), I (5), and J (6), were isolated from olibanum, the exuded gum-resin from Boswellia carterii BIRDW. Their structures including the absolute configuration were determined by chemical and physicochemical evidence. Among the constituents, olibanumols A (1), H (4), and I (5), and isofouquierol (12) exhibited nitric oxide production inhibitory activity in lipopolysaccharide-activated mouse peritoneal macrophages.