Levistolide A ameliorates fibrosis in chronic kidney disease via modulating multitarget actions in vitro and in vivo.

AIMS: The increasing incidence of chronic kidney disease (CKD) urgently calls for effective nephroprotective agents. Traditional Chinese Medicine Angelica sinensis and its formula are well known for CKD therapy, but the underlying mechanisms and effective substances of reno-protective effects remain unclear. To this end, we isolated eleven ligustilide dimers (1-11) from A. sinensis and examined the molecular mechanism of their nephroprotective effects. MAIN METHODS: Because of internal RAS playing an important role in CKD, we used renin expression as a target and screened preliminarily for antifibrotic effects of ligustilide dimers (1-11) by constructing a dual luciferase reporter gene in vitro. Furthermore, the reno-protective effects of the ligustilides and their underlying mechanism were investigated in TGF-ß1-stimulated HK-2 cells and 5/6 nephrectomy (Nx) mice. KEY FINDINGS: The ligustilide dimers exhibited anti-fibrotic effects by inhibiting human renin (hREN) promoter activity to decrease renin expression and down-regulate the expression of fibrosis-related factors, including α-SMA, collagen I, and fibronectin in vitro. Levistolide A (LA) and angeolide keto ester (AK) were screened out to identify their ability and underlying mechanism for treating CKD. Experimental validation further indicated that LA or AK treatment inhibited the expression of key molecules in RAS, TGF-ß1/Smad, and MAPK pathways to downregulate ECM deposition. Furthermore, LA obviously meliorated renal injury in 5/6 Nx mice through ameliorating oxidant stress, inflammation, apoptosis and renal fibrosis. SIGNIFICANCE: The experimental results demonstrated that ligustilide dimers were potential nephroprotective agents. LA might be an attractive drug candidate for renin-targeted CKD therapy.

Phenolipid JE improves metabolic profile and inhibits gluconeogenesis via modulating AKT-mediated insulin signaling in STZ-induced diabetic mice.

Phenolipids are characteristic phytochemicals of Syzygium genus. However, the antidiabetic potential and underlying molecular mechanism of these components are not fully elucidated. Herein, we studied the anti-diabetic effects of jambone E (JE), a phenolipid from S. cumini, with in vitro and in vivo models. Data from current study showed that JE enhanced glucose consumption and uptake, promoted glycogen synthesis, and suppressed gluconeogenesis in insulin resistant (IR)-HepG2 cells and primary mouse hepatocytes. JE also attenuated streptozotocin-induced hyperglycemia and hyperlipidemia in type 1 diabetic (T1D) mice. Eleven metabolites (e.g. trimethylamine n-oxide, 4-pyridoxic acid, phosphatidylinositol 39:4, phenaceturic acid, and hippuric acid) were identified as potential serum biomarkers for JE's antidiabetic effects by an untargeted metabolomics approach. The further molecular mechanistic study revealed that JE up-regulated phosphorylation levels of protein kinase B (AKT), glycogen synthase kinase 3 beta, and forkhead box O1 (FoxO1), promoted nuclear exclusion of FoxO1 whilst decreased gene expression levels of peroxisome proliferator-activated receptor gamma coactivator-1 alpha, phosphoenolpyruvate carboxykinase and glucose 6-phosphatase in IR-HepG2 cells and T1D mice. Our data suggested that JE might be a potent activator for AKT-mediated insulin signaling pathway, which was confirmed by the usage of AKT inhibitor and AKT-target siRNA interference, as well as the cellular thermal shift assay. Findings from the current study shed light on the anti-diabetic effects of phenolipids in the Syzygium species, which supports the use of medicinal plants in the Syzygium genus for potential pharmaceutical applications.

The Anti-inflammatory Effects of Isoflavonoids from Radix Astragali in Hepatoprotective Potential against LPS/D-gal-induced Acute Liver Injury.

Radix Astragali (RA) is an important Traditional Chinese Medicine widely used in the treatment of various diseases, such as pneumonia, atherosclerosis, diabetes, kidney and liver fibrosis. The role of isoflavonoids from RA in the treatment of liver injury remains unclear. The study aimed to explore hepatoprotective and anti-inflammatory effects of isoflavonoids from Astragalus mongholicus. Network pharmacological analysis showed that RA had a multi-target regulating effect on alleviating liver injury and inhibiting inflammation through its active ingredients, among which isoflavones were closely related to its key molecular targets. The anti-inflammatory and liver protection effects of isoflavonoids of RA were investigated using lipopolysaccharide (LPS)-induced RAW 264.7 cells in vitro and LPS/D-galactosamine (D-gal)-induced acute liver injury mice in vivo. The experimental results showed that methylnissolin (ML) and methylnissolin-3-O-ß-D-glucoside (MLG) presented more notable anti-inflammatory effects. Both of them suppressed the release of pro-inflammatory cytokines, such as iNOS, COX-2, IL-1ß, IL-6, and TNF-α in LPS-stimulated RAW 264.7 cells. In vivo investigation demonstrated that ML markedly meliorated liver injury in LPS/D-gal-induced mice. Western blot results revealed that ML and MLG down-regulated the expression of proinflammatory cytokines via NF-κB signaling pathway. The isoflavonoids, methylnissolin (ML), and methylnissolin-3-O-ß-D-glucoside (MLG), play a vital role in the hepatoprotective and anti-inflammatory effects of RA.

Discovery, preparation and characterization of lipid-lowering alkylphenol derivatives from Syzygium jambos fruit.

The chemical characteristics and hypolipidemic effects of alkylphenols in the fruit of Syzygium jambos were investigated in this study. Three cardanols (1-3; 1 as a new compound) and three alkylresorcinols (4-6) were isolated and identified from S. jambos fruit. Cardanols 1 and 2 (10-40 µM) suppressed lipids accumulation and reduced triglyceride content in oleic acid-overloaded HepG2 cells via the activation of AMPK/PPARα signaling pathways. Furthermore, the biological distribution of cardanols after an oral intake in mice was investigated. Compound 2 was detected in mice plasma, feces, and adipose tissues after a single oral intake (80 mg/kg body weight). In addition, an alkylphenols-enriched S. jambos fruit extract containing two bioactive compounds (95.9 and 198.6 µg/mg of compounds 1 and 2, respectively) was prepared. Findings from the current study highlight the potential usage of cardanols as well as S. jambos fruit for the management of dyslipidemia.

Riligustilide alleviates hepatic insulin resistance and gluconeogenesis in T2DM mice through multitarget actions.

Riligustilide (RG), one of the dimeric phthalides of Angelica sinensis and Ligusticum chuanxiong, was confirmed effective against many diseases. However, its effects on type 2 diabetes mellitus (T2DM) and the underlying molecular mechanisms have not been clearly elucidated yet. The current study was designed to investigate the hypoglycemic potential by which RG affects the pathogenesis of T2DM. Comprehensive insights into the effects and underlying molecular mechanisms of RG on attenuating aberrant metabolism of glucose were determined in high-fat diet-induced T2DM mice and insulin-resistant (IR) HepG2 cells. In high-fat diet-induced C57BL/6J mice, RG administration significantly reduced hyperglycemia, decreased hyperinsulinemia, and ameliorated glucose intolerance. Mechanistically, RG activated PPARγ and insulin signaling pathway to improve insulin sensitivity, and increase glucose uptake as well as glycogenesis. In addition, RG also upregulated AMPK-TORC2-FoxO1 axis to attenuate gluconeogenesis in vivo and in vitro. According to the findings, RG may be a promising candidate for the treatment of T2DM.

New phenolic glycosides from Anemone chinensis Bunge and their antioxidant activity.

ABATRACTNine compounds, five phenolic glycosides (1, 2, 4-6), three phenylpropanoids (7-9), and a furanone glycoside (3), were isolated from aqueous soluble extract of the dried roots of Anemone chinensis Bunge. The structures of new compounds (1-4) were elucidated by comprehensive spectroscopic data analysis as well as chemical evidence. Pulsatillanin A (1) demonstrated significant antioxidant effects through scavenging free radical in DPPH assay, and relieved the oxidative stress in LPS-induced RAW 264.7 cells by reducing ROS production, enhancing antioxidant enzyme SOD activity, replenishing depleted GSH in a dose-dependent manner. Western blot analysis revealed that 1 showed antioxidant activity via activating Nrf2 signaling pathway.[Formula: see text].

Chemical characterization, antiproliferative and antifungal activities of Clinacanthus nutans.

Clinacanthus nutans Lindau (Family: Acanthaceae) is a medicinal herb widely distributed in the tropic and subtropic areas of Asia. C. nutans is traditionally consumed as vegetable or herbal tea, as well as a folk medicine for anticancer and antifungal activities. However, to date, chemical constituent responsible for observed health beneficial effects of this medicinal plant is not clear. In the current study, 32 compounds (1-32), including three new megastigmanes (1-3) were isolated from the aerial parts of C. nutans. Their structures were elucidated on the basis of comprehensive NMR, MS, and CD spectroscopic data analysis, as well as chemical hydrolysis. Among the isolates, cycloartane triterpenoids (9, 10, and 12) displayed moderate anti-proliferative effects against HepG2 cell growth with IC50 values ranging from 9.12 to 19.89 µM. Data obtained from flow cytometry analysis and western blotting assays revealed that compounds 9 and 12 induced apoptosis of HepG2 cells by modulating the expression of proteins associated to mitochondrial-mediated apoptotic pathway. Furthermore, megastigmanes 1, 2, 7, and 8 enhanced the anti-Candida albicans activity of amphotericin B (AmB), supporting the synergistic effects between megastigmanes and AmB. This is the first report of anticancer and antifungal potential of cycloartane triterpenoids and megastigmanes in C. nutans, which shed useful insights on the relationship between C. nutans's chemical constituent and its beneficial effects to health. Findings from this study support further development of this medicinal plant for potential pharmaceutical applications.

Discovery of Anti-TNBC Agents Targeting PTP1B: Total Synthesis, Structure-Activity Relationship, In Vitro and In Vivo Investigations of Jamunones.

Twenty-three natural jamunone analogues along with a series of jamunone-based derivatives were synthesized and evaluated for their inhibitory effects against breast cancer (BC) MDA-MB-231 and MCF-7 cells. The preliminary structure-activity relationship revealed that the length of aliphatic side chain and free phenolic hydroxyl group at the scaffold played a vital role in anti-BC activities and the methyl group on chromanone affected the selectivity of molecules against MDA-MB-231 and MCF-7 cells. Among them, jamunone M (JM) was screened as the most effective anti-triple-negative breast cancer (anti-TNBC) candidate with a high selectivity against BC cells over normal human cells. Mechanistic investigations indicated that JM could induce mitochondria-mediated apoptosis and cause G0/G1 phase arrest in BC cells. Furthermore, JM significantly restrained tumor growth in MDA-MB-231 xenograft mice without apparent toxicity. Interestingly, JM could downregulate phosphatidylinositide 3-kinase (PI3K)/Akt pathway by suppressing protein-tyrosine phosphatase 1B (PTP1B) expression. These findings revealed the potential of JM as an appealing therapeutic drug candidate for TNBC.

Chemical Characterization and Hepatoprotective Effects of a Standardized Triterpenoid-Enriched Guava Leaf Extract.

Nutraceutical/pharmaceutical agents capable of maintaining redox and inflammation homeostasis are considered as candidates for the prevention and/or treatment of liver diseases. Psidium guajava (commonly known as guava) leaf is a commercially available functional food that has been reported to possess hepatoprotective property. However, the hepatoprotective constituents in guava leaf are not known. In the current study, a standardized triterpenoid-enriched extract of guava leaves (TGL) was developed. A new ursolic acid derivative, namely 2α,3ß,6ß,23,30-pentahydroxyurs-11,13(18)-dien-28,20ß-olide (1), and 23 known triterpenoids were isolated and identified from TGL. The hepatoprotective effects of TGL were evaluated through a model using acetaminophen (APAP)-exposed C57BL/6 male mice. Pretreatment of TGL (75 and 150 mg/kg) restored the mice hepatic architecture, improved the serum ALT and AST levels, and reduced the hepatic ROS and MDA contents. Further molecular mechanistic study revealed that TGL modulated Nrf2 and MAPK signaling pathways to alleviate APAP-induced oxidative and inflammatory stress in liver. In addition, the new compound 1 from TGL showed protective effects against APAP-induced cytotoxicity via activation of the Nrf2 pathway in HepG2 cells. Overall, this is the first report on the hepatoprotective effects of a standardized triterpenoid-enriched extract of guava leaves, which supports its potential nutraceutical application in liver disease management.

Guavinoside B from Psidium guajava alleviates acetaminophen-induced liver injury via regulating the Nrf2 and JNK signaling pathways.

Benzophenone glycosides are a major type of polyphenols present in guava. To date, there is still poor understanding of the relationship between benzophenone glycosides and the hepatoprotective effects attributed to this edible fruit. Herein, the protective effects of guavinoside B (GUB), a main benzophenone glycoside present in guava fruit, against acetaminophen (APAP)-induced liver injury were investigated in vitro and in vivo. Fluorescence measurement demonstrated that GUB (at a concentration of 30 µM) significantly reduced the intracellular ROS levels in APAP-treated HepG2 cells. In addition, GUB (100 mg kg-1 d-1) pretreatment markedly alleviated APAP-induced hepatocyte infiltration and necrosis in C57BL/6 mice, and improved serum and hepatic biochemical parameters, such as ALT, AST, SOD, GSH, ROS, MDA, and TNF-α levels. RT-PCR and western blot experiments revealed that GUB up-regulated Nrf2, GCLC and NQO1, while reducing p-JNK gene expression in the liver. The fermentation experiment further revealed that the displayed beneficial effects of GUB in vivo might be related to the gut microbial metabolite gallic acid. These promising data suggested that GUB showed potent hepatoprotective effects through regulating the Nrf2 and JNK signaling pathways. Further investigation of the absorption and metabolism of benzophenones would be warranted to promote the utilization of these phenolics as functional food ingredients against oxidative stress-induced chronic diseases.

New anti-inflammatory withanolides from Physalis pubescens fruit.

Physalis pubescens L. is a medicinal plant widely cultivated in northeast of China. Investigation on the extract of P. pubescens fruit led to the isolation and identification of four new withanolides, namely, physapubescins J-M (1, 2, 4 and 5), together with four known analogues (3, 6-8) and fifteen other compounds. Their structures were elucidated on the basis of comprehensive NMR, MS, and ECD spectroscopic data analysis. Among isolates, physapubescin J (1) contained an unusual sulphide linkage, and four withanolides (3, 5, 7 and 8) showed anti-inflammatory potential in LPS-induced RAW264.7 cells. This study supports P. pubescens fruit could be a valuable source of withanolides. Further studies to investigate anti-inflammatory activities of isolated withanolides using in vivo models are warranted.

Barringtogenol C-type Triterpenoid Saponins from the Stem Bark of Norway Maple (Acer Platanoides).

Four new barringtogenol C-type triterpenoid saponins, namely acerplatanosides A - D (1: -4: ), along with 22 known compounds (5: -26: ), were isolated from the stem bark of Norway maple (Acer platanoides). Their structures were elucidated on the basis of comprehensive spectroscopic analyses and chemical hydrolysis. This is the first report of triterpenoid saponins isolated from Norway maple. Compounds 1, 3: , and 4: showed cytotoxicity against 4 human cancer cell lines with IC50 values ranging from 9.4 to 39.5 µM.

The anti-inflammatory effects of jiangrines from Jiangella alba through inhibition of p38 and NF-κB signaling pathways.

Three pyrrol-2-aldehyde derivatives, including one new compound, jiangrine G (JG), two known compounds, jiangrine A (JA), and pyrrolezanthine (PZ), were isolated from the fermentation broth of Jiangella alba associated with a traditional Chinese medicinal plant Maytenus austroyunnanensis. The structure of jiangrine G was elucidated by a detailed spectroscopic data analysis including data from CD spectra. The anti-inflammatory activities assay demonstrated that JG and JA suppressed the production of pro-inflammatory cytokines including NO, IL-1ß, and IL-6 as well as inhibited the expression of iNOS in LPS-induced RAW 264.7 cells in a dose-dependent manner. While high concentration of PZ dramatically suppressed the protein expression of TNF-α, but stimulated the release of IL-1ß and IL-6. Western blot results revealed that JG, JA, and PZ modulated the expression of pro-inflammatory cytokines via MAPK p38 and NF-κB signaling pathways. For the unique structure of PZ, difference from JG and JA, the signaling pathway involved in mediating its effects on regulating the synthesis of IL-1ß and IL-6 are probably more complicated than that of JG and JA.

New Acylated Phenolic Glycosides with ROS-Scavenging Activity from Psidium guajava Leaves.

Reactive oxygen species and subsequent oxidative stress are reported to play important roles in chronic metabolic diseases. Plant-derived polyphenols, especially food-derived phenolics, have attracted a lot of attention due to their potential usage against oxidative stress-related diseases. The leaf of Psidium guajava (known as guava) is regarded as a good resource of polyphenols and its products are commercially available in Japan as functional foods against multiple chronic metabolism disorders. In the course of finding novel polyphenols with antioxidative activities from guava leaf, 11 acylated phenolic glycosides (1-11), including 5 new oleuropeic acid-conjugated phenolic glycosides, named guajanosides A-E (1, 2, and 5-7), along with 17 known meroterpenoides (12-28), were isolated and identified. Their structures were determined by spectroscopic data analysis, chemical degradation, and acid hydrolysis. Compounds 1, 2, and 5-11 displayed potent reactive oxygen species-scavenging activity in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. Western blot revealed that compound 6 markedly increased the expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), NAD(P)H quinone dehydrogenase 1 (NQO1), and the glutamate-cysteine ligase catalytic subunit. The current study revealed the presence of oleuropeic acid-derived phenolic glycosides in guava leaf and highlighted the potential usage of this type of phenolics against oxidative stress-related metabolic diseases via activation of the Nrf2 signaling pathway.

Paricalcitol accelerates BACE1 lysosomal degradation and inhibits calpain-1 dependent neuronal loss in APP/PS1 transgenic mice.

BACKGROUND: Recent studies have revealed that vitamin D deficiency may increase the risk of Alzheimer's disease, and vitamin D supplementation may be effective strategy to ameliorate the neurodegenerative process in Alzheimer's disease patients. Paricalcitol (PAL), a low-calcemic vitamin D receptor agonist, is clinically used to treat secondary hyperparathyroidism. However, the potential application of PAL for treating neurodegenerative disorders remains unexplored. METHODS: The APP/PS1 mice were intraperitoneally injected with PAL or vehicle every other day for 15 weeks. The ß-amyloid (Aß) production was confirmed using immunostaining and enzyme linked immunosorbent assay. The underlying mechanism was verified by western blot and immunostaining in vivo and in vitro. FINDINGS: Long-term PAL treatment clearly reduced ß-amyloid (Aß) generation and neuronal loss in APP/PS1 transgenic mouse brains. PAL stimulated the expression of low-density lipoprotein receptor-related protein 1 (LRP1) possibly through inhibiting sterol regulatory element binding protein-2 (SREBP2); PAL also promoted LRP1-mediated ß-site APP cleavage enzyme 1 (BACE1) transport to late endosomes, thus increasing the lysosomal degradation of BACE1. Furthermore, PAL diminished 8-hydroxyguanosine (8-OHdG) generation in neuronal mitochondria via enhancing base excision repair (BER), resulting in the attenuation of calpain-1-mediated neuronal loss. INTERPRETATION: The present data demonstrate that PAL can reduce Aß generation through accelerating BACE1 lysosomal degradation and can inhibit neuronal loss through suppressing mitochondrial 8-OHdG generation. Hence, PAL might be a promising agent for treating Alzheimer's disease. FUND: This study was financially supported by the Natural Science Foundation of China (U1608282).

Jamun (Eugenia jambolana Lam.) Fruit Extract Prevents Obesity by Modulating the Gut Microbiome in High-Fat-Diet-Fed Mice.

SCOPE: Published data support that gut microbiota play an important role in the pathological process of obesity and related metabolic disorders. In the current study, it is investigated whether a standardized extract from Jamun (Eugenia jambolana), a widely consumed tropical fruit, could alleviate obesity and alter gut microbial community in high-fat diet (HFD)-fed mice. METHODS AND RESULTS: C57BL/6 mice are fed either a standard diet (SD) or HFD with or without Jamun fruit extract (JFE; 100 mg kg-1 day-1 ) by oral gavage for 8 weeks. JFE supplementation significantly alleviated diet-induced obesity, insulin resistance, and liver steatosis. JFE supplementation also improved HFD-induced gut dysbiosis by restoring the ratio of Firmicutes to Bacteroidetes as revealed by 16S rDNA analyses. The relative abundance of certain genera, as well as levels and proportion of intestinal-derived short-chain fatty acids are improved in JFE-treated mice in comparison to the HFD-fed control group. CONCLUSION: These promising data show the potential association between gut microbiota modulation and metabolism improvement of the JFE administration, and support the utilization and further investigation of Jamun fruit as a dietary intervention strategy for the prevention of obesity and related metabolic disorders.

Riligustilide Attenuated Renal Injury by the Blockade of Renin.

BACKGROUND/AIMS: Nephropathy related with renin can be alleviated with ACE-inhibitors or AT1R blockers, whereas they might be ineffective after long-term administration because of a feedback production of enhanced renin. Therefore, it is urgent to develop a new category of anti-nephropathy medicine directly targeting renin. Riligustilide (C20), originally isolated from the Chinese herb Ligusticumporteri, a rhizome, was confirmed effective against many diseases. METHODS: The therapeutic effect of C20 on renal injury and its underlying mechanism were investigated in three different nephrotic models, which were spontaneously hypertension rats (SHR) model, diabetic nephropathy in BTBR ob/ob mice model and 5/6-nephrectomized (5/6NX) rats model. RESULTS: The intensity of kidney fibrosis was extensively decreased in the C20-treated rats compared to the vehicle animals. C20 significantly alleviated renal injury much more in 5/6 NX rats than in vehicle group. The rats in 5/6 NX without administrated C20 developed albuminuria earlier with more severe symptoms. Additionally, our findings showed that C20 down-regulated the renin expression and relocation of CREB-CBP complex in vivo and in vitro. CONCLUSION: C20 plays importantly reno-protective roles most likely through the relocation of CREB-CBP complex.

Phenolics from Eugenia jambolana seeds with advanced glycation endproduct formation and alpha-glucosidase inhibitory activities.

Published data suggest that dietary-derived phenolics exert beneficial effects against hyperglycemia-mediated diseases, such as diabetes, through inhibiting the formation of advanced glycation endproducts (AGEs) and carbohydrate hydrolyzing enzyme activities. In the course of our investigation on the edible berry, Eugenia jambolana (known as Jamun), 21 phenolics (1-21) were isolated and identified from its seeds. Among these, one compound (1) is new and eleven compounds (3, 6, 9-13, 17, and 19-21) are being reported from E. jambolana for the first time. The anti-AGE activities of thirteen pure isolates (2-7, 9-12, 14, 15, and 20) were either comparable or superior to the synthetic anti-glycation agent, aminoguanidine, at three test concentrations (20, 50, and 100 µM) in the BSA-fructose assay. Most of these phenolics with anti-AGE activity exhibited potent free radical scavenging activity in the DPPH assay, and attenuated intracellular levels of LPS-induced reactive oxygen species in RAW264.7 macrophage. In addition, compounds 2-6, and 14 showed superior α-glucosidase inhibitory activity (IC50 = 5.0-21.2 µM) compared to the clinical α-glucosidase inhibitor, acarbose (IC50 = 289.9 µM). This is the first report of the anti-AGE effects of compounds 2-6 and 9-12, and α-glucosidase inhibitory activities of compounds 3-6, 9, 11 and 14. The current study supports the role of phenolics in the antidiabetic properties attributed to this edible berry, and warrants further animal studies to evaluate their potential as dietary agents for the prevention and/or therapy of hyperglycemia-mediated diseases.

Hypoglycemic and hypolipidemic effects of triterpenoid-enriched Jamun (Eugenia jambolana Lam.) fruit extract in streptozotocin-induced type 1 diabetic mice.

The edible berries of Eugenia jambolana Lam. (known as Jamun) are consumed in various parts of the world. Our previous studies revealed that a triterpenoid-enriched Jamun fruit extract (TJFE) showed beneficial effects on glucose homeostasis in non-diabetic mice. Herein, the anti-diabetic effects of TJFE (100 mg kg-1 by oral gavage for ten days) were evaluated in streptozotocin (STZ)-induced type 1 diabetic mice. TJFE significantly attenuated STZ-induced hyperglycemia and glucose intolerance, suppressed the abnormal elevation of hepatic gluconeogenesis, and improved dyslipidemia in the mice. Histopathology and mechanism-based studies revealed that TJFE preserved the architecture and function of pancreatic islets, attenuated insulin secretion deficiency, enhanced insulin/Akt signaling transduction, reduced lipogenic gene expression, and prevented the abnormal activation of Erk MAPK in the liver tissues of the STZ-induced diabetic mice. The current study adds to previously published data supporting the potential beneficial effects of this edible fruit on diabetes management.

New Sesquiterpenoids from Eugenia jambolana Seeds and Their Anti-microbial Activities.

Twenty four sesquiterpenoids, 1-24, including 11 new sesquiterpenoids, jambolanins A-K, and two new norsesquiterpenoids, jambolanes A and B, along with six known triterpenoids, were isolated from the seeds of Eugenia jambolana fruit. Their structures were elucidated on the basis of NMR and MS spectrometry data analysis. Among the isolates, compound 13 possessed a rare 6,7-seco-guaiene skeleton, and compounds 14 and 15 were norsesquiterpenoids containing a spiro[4.4]nonane skeleton. Antimicrobial assay evaluation revealed that sesquiterpenoids, 4, 5/6, 17, 19, 21, 23, and 24 inhibited the growth of the Gram-positive bacterium, Staphylococcus aureus. The current study advances scientific knowledge of E. jambolana phytochemicals and suggests that its sesquiterpenoids may contribute, in part, to the anti-infective effects attributed to the edible fruit of this plant.