Astraoleanosides E-P, oleanane-type triterpenoid saponins from the aerial parts of Astragalus membranaceus Bunge and their ß-glucuronidase inhibitory activity.

Historically, Astragalus membranaceus Bunge has been used as a beneficial medicinal plant, particularly in the Asian traditional medical systems, for the treatment of various human diseases such as stomach ulcers, diarrhea, and respiratory issues associated with phlegm. In this study, a phytochemical characterization of the aerial parts of A. membranaceusled to the isolation of 29 oleanane-type triterpenoid saponins, including 11 new compounds named astraoleanosides E-P (6-9, 13, 14, 18-22), as well as 18 known ones. The structures of these compounds were elucidated using nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry. Among them, astraoleanoside H (9) and cloversaponin III (15) demonstrated the most potent ß-glucuronidase inhibitory activities, with IC50 values of 21.20 ± 0.75 and 9.05 ± 0.47 µM, respectively, compared to the positive control d-saccharic acid 1,4-lactone (IC50 = 20.62 ± 1.61 µM). Enzyme kinetics studies were then conducted to investigate the type of inhibition exhibited by these active compounds. In addition, the binding mechanism, key interactions, binding stability, and dynamic behavior of protein-ligand complexes were investigated through in silico approaches, such as molecular docking and molecular dynamics simulations. These findings highlight the promising potential of triterpenoid saponins from A. membranaceus as lead compounds for ß-glucuronidase inhibitors, offering new possibilities for the development of therapeutic agents targeting various diseases where ß-glucuronidase plays a crucial role.

Evaluating the toxicity of the roots of Asarum heterotropoides var. mandshuricum extracted using the decoction method: Genotoxicity, single-dose toxicity, and 13-week repeated-dose toxicity studies.

ETHNOPHARMACOLOGICAL RELEVANCE: The roots of Asarum heterotropoides F. Maekawa var. mandshuricum F. Maekawa (AR) is a traditional herbal medicine used across Asia, including Korea, China, and Japan. AR exhibits a range of biological activities, such as anti-inflammatory, anti-cancer, cold treatment, and anti-nociceptive effects. Various extraction methods, including decoction, which utilizes traditional knowledge and techniques. The AR decoction extract expected to contain fewer toxicants and have reduced toxicity due to the use of hot water in the extraction process. However, scientific evidence on the toxicity of AR decoction extracts is lacking, necessitating further studies for safe usage. AIM OF THE STUDY: This study aimed to evaluate the genotoxicity and toxicity of single and repeated administration of AR decoction extracts. MATERIALS AND METHODS: The genotoxicity was assessed using a bacterial reverse mutation (Ames test), an in vitro mammalian chromosome aberration test (CA test), and an in vivo micronucleus test (MN test) in Sprague-Dawley (SD) rats. The general toxicity was evaluated through single-dose and 13-week repeated-dose toxicity studies. In the single-dose toxicity study, 40 SD rats were orally administered AR decoction extract at doses of 1000, 2000, and 5000 mg/kg. In the 13-week repeated-dose toxicity study, 140 SD rats received daily oral doses of 0, 250, 500, 1000, 2000, and 5000 mg/kg of AR decoction extract. RESULTS: The genotoxicity tests revealed that AR decoction extract was not genotoxic. The single-dose toxicity study showed no changes in body weight, clinical pathology, or macroscopic findings, with the approximate lethal dose (ALD) exceeding 5000 mg/kg. The 13-week repeated-dose toxicity study demonstrated no treatment-related changes in body weight, general symptoms, hematology, clinical chemistry, or urinalysis. Histopathological findings revealed hyperplasia of squamous cells in the forestomach after AR decoction extract administration, a treatment-related effect that resolved during the recovery period. The no observed adverse effect level (NOAEL) for both male and female rats was estimated to be 2000 mg/kg. CONCLUSIONS: This study establishes the non-toxic dose of AR decoction extract, providing a foundation for further non-clinical and clinical evaluations AR safety.

Genotoxicity assessment of root extracts of Paeonia lactiflora Pall.

The roots of Paeonia lactiflora Pall., (Paeoniae Radix, PL) are a well-known herbal remedy used to treat fever, rheumatoid arthritis, systemic lupus erythematosus, hepatitis, and gynecological disorders in East Asia. Here we evaluated the genetic toxicity of PL extracts (as a powder [PL-P] and hot-water extract [PL-W]) in accordance with the Organization for Economic Co-operation and Development guidelines. The Ames test revealed that PL-W was not toxic to S. typhimurium strains and E. coli in absence and presence of the S9 metabolic activation system at concentrations up to 5000 µg/plate, but PL-P produced a mutagenic response to TA100 in the absence of S9 mix. PL-P was cytotoxic in in vitro chromosomal aberrations (more than a 50 % decrease in cell population doubling time), and it increased the frequency of structural and numerical aberrations in absence and presence of S9 mix in a concentration-dependent manner. PL-W was cytotoxic in the in vitro chromosomal aberration tests (more than a 50 % decrease in cell population doubling time) only in the absence of S9 mix, and it induced structural aberrations only in the presence of S9 mix. PL-P and PL-W did not produce toxic response during the in vivo micronucleus test after oral administration to ICR mice and did not induce positive results in the in vivo Pig-a gene mutation and comet assays after oral administration to SD rats. Although PL-P showed genotoxic in two in vitro tests, the results from physiologically relevant in vivo Pig-a gene mutation and comet assays illustrated that PL-P and PL-W does not cause genotoxic effects in rodents.

Evaluation of genotoxicity and 13-week subchronic toxicity of root of Asarum heterotropoides var. seoulense (Nakai) Kitag.

ETHNOPHARMACOLOGICAL RELEVANCE: Asarum heterotropoides var. seoulense (Nakai) Kitag is a traditional herbal medicine used in Korea and China. It is effective in aphthous stomatitis, local anesthesia, headache, toothache, gingivitis, and inflammatory diseases. However, information on the toxicity of the root of Asarum heterotropoides var. seoulense (Nakai) Kitag (AR) is limited. Therefore, preclinical toxicity studies on AR are needed to reduce the risk of excessive intake. AIM OF THE STUDY: We aimed to evaluate genotoxicity and the potential toxicity due to repeated administration of AR powder. MATERIALS AND METHODS: In vitro bacterial reverse mutation assay (Ames), in vitro chromosomal aberration assay (CA), and in vivo micronucleus (MN) assay in ICR mice were conducted. As positive results were obtained in Ames and CA assays, alkaline comet assay and pig-a gene mutation test were conducted for confirmation. For evaluating the general toxicity of AR powder, a 13-week subchronic toxicity test was conducted, after determining the dose by performing a single and a 4-week dose range finding (DRF) test. A total of 152 Sprague-Dawley (SD) rats were orally administered AR powder at doses of 0, 150, 350, 500, 1000, and 2000 mg/kg/day in the 13-week subchronic toxicity test. Hematology, clinical chemistry, urinalysis, organ weight, macro-, and microscopic examination were conducted after rat necropsy. RESULTS: AR powder induced genotoxicity evidenced in the Ames test at 187.5, 750, 375, and 1500 µg/plate of TA100, TA98, TA1537, and E. coli WP2uvrA in the presence and absence of S9, respectively; CA test at 790 µg/mL for 6 h in the presence of S-9; 75 µg/mL for 6 h in the absence of S-9, and 70 µg/mL for 22 h in the absence of S-9 in the stomach in the comet assay but not in MN and pig-a assays. In the 13-week subchronic toxicity study, clinical signs including irregular respiration, noisy respiration, salivation, and decreased body weight or food consumption were observed in males and females in the 2000 mg/kg/day group. In hematology tests, clinical chemistry, urinalysis, organ weight, and macroscopic examination, changes were observed in the dose groups of 500 mg/kg/day and above. Microscopic examination revealed hyperplasia of the stomach as a test-related change. Hepatocellular adenoma and changes in liver-related clinical chemistry parameters were observed. The rat No Observed Adverse Effect Level (NOAEL) was 150 mg/kg/day in males and <150 mg/kg/day in females. CONCLUSIONS: AR powder is potentially toxic to the liver and stomach and should be used with caution in humans. A long-term study on carcinogenicity is necessitated because DNA damage or changes in tissue lesions were observed in SD rats.

Structures and antiosteoclastogenic activity of compounds isolated from edible lotus (Nelumbo nucifera Gaertn.) leaves and stems.

One new 1,4-bis-phenyl-1,4-butanedione glycoside (14), one new eudesmane-type sesquiterpenoid (16), and 16 known compounds were isolated from the leaves and stems of Nelumbo nucifera Gaertn. The structures of the isolated compounds were elucidated by interpretation of their 1D and 2D NMR spectroscopic and HRESIMS data. Time-dependent density functional theory calculations and Electronic Circular Dichroism (ECD) spectroscopy was used to determine absolute configurations of the new eudesmane-type sesquiterpenoid (16). All the isolated compounds were examined for their antiosteoclastogenic activity. Preliminarily results of the TRAP staining on RAW 264.7 cells indicated that compounds 1 and 11 possess potential inhibitory effects on RANKL-induced osteoclast formation. Further bioassay investigation was carried out to reveal that compounds 1 and 11 suppressed RANKL-induced osteoclast formation in a concentration-dependent manner with the inhibition up to 55% and 78% at the concentration of 10 µM, respectively. In addition, the structure-activity relationship analysis showed that the 1,3-dioxole substitute and the double bond at C-6a/C-7 in the aporphine skeleton may be responsible for the antiosteoclastogenic activity. The findings provided valuable insights for the discovery and structural modification of aporphine alkaloids as the antiosteoclastogenic lead compounds.

PTP1B and α-glucosidase inhibitory activities of the chemical constituents from Hedera rhombea fruits: Kinetic analysis and molecular docking simulation.

In this study, we present the first investigation of Hedera rhombea Bean fruit, which led to the isolation of six undescribed compounds including two megastigmane glucosides, two rare 1,4-dioxane neolignanes, and two quinic acid derivatives, together with 26 known compounds. Their structures and absolute configurations were elucidated by extensive analysis of NMR spectroscopic data, HRMS, and ECD calculations. This is the first report on the isolation of methyl 3-O-caffeoyl-5-O-p-coumaroylquinate from a natural source. Among the isolated compounds, falcarindiol and caffeoyltryptophan showed significant PTP1B inhibition with IC50 values of 7.32 and 16.99 µM, respectively, compared to those of the positive controls [sodium orthovanadate (IC50 = 17.96 µM) and ursolic acid (IC50 = 4.53 µM)]. These two compounds along with several other compounds displayed significant α-glucosidase inhibitions with IC50 values ranging from 12.88 to 91.89 µM, stronger than that of the positive control (acarbose, IC50 = 298.07 µM). Enzyme kinetic analysis indicated that caffeoyltryptophan and falcarindiol displayed competitive and mixed-type PTP1B inhibition, respectively, whereas the α-glucosidase inhibition type was mixed-type for caffeoyltryptophan and uncompetitive (rarely reported for a-glucosidase inhibitors) for falcarindiol. In addition, molecular docking results showed that these active compounds exhibited good binding affinities toward both PTP1B and α-glucosidase with negative binding energies. The results of the present study demonstrate that these active compounds might be beneficial in the treatment of type 2 diabetes.

Structural characterization of prenylated compounds from Broussonetia kazinoki and their antiosteoclastogenic activity.

An undescribed 1,3-diphenylpropane derivative, kazinol V and six undescribed prenylated flavonoids, broussonols F-H and broussonols K-M were isolated from the roots of Broussonetia kazinoki Siebold, together with 12 known compounds. This is the first report of the isolation and structure determination of broussonol I from a natural source. The chemical structure of the undescribed compounds was determined using conventional NMR and HRMS data. Absolute configurations were assigned using time-dependent density functional theory calculations and Electronic Circular Dichroism (ECD) spectroscopy. The isolated compounds were screened for their effects on RANKL-induced osteoclast formation using RAW264.7 cells. Among them, broussonols F, G, and K showed strong, dose-dependent antiosteoclastogenic activities. Broussonol K exhibited the most potent inhibitory activity and possessed bone resorption suppressive activity.

Flavonoids from the peels of Citrus unshiu Markov. and their inhibitory effects on RANKL-induced osteoclastogenesis through the downregulation of c-Fos signaling in vitro.

Phytochemical investigation of Citrus unshiu peels led to the isolation of eight new flavonols (7-9, 11-15) and sixteen known compounds (1-6, 10, 16-24). Their structures were elucidated using spectroscopic analysis (1D, 2D NMR, and HR-MS). Besides, all isolated compounds (1-24) were evaluated for their inhibitory effects on receptor activator of RANKL-induced osteoclastogenesis in BMMs. Among them, dimethylmikanin (1), quercetogetin (2), 3,3',4',5,7,8-hexamethoxyflavone (3), 3-methoxynobiletin (4) showed a significant inhibitory effect on RANKL-induced osteoclast differentiation at a concentration of 10 µM. Moreover, 3-methoxynobiletin (4) suppressed RANKL-induced osteoclastogenesis by decreasing the number of osteoclasts and osteoclast actin-ring formation in a dose-dependent manner without causing any cytotoxic effects on BMMs. At the molecular level, 3-methoxynobiletin (4) inhibited RANKL-induced c-Fos expression and subsequently NFATc1 activation, as well as the expression of osteoclastogenesis-related marker genes c-Src and CtsK. These findings suggested that 3-methoxynobiletin (4) attenuated osteoclast differentiation by inhibiting RANKL-mediated c-Fos signaling and that it may have therapeutic potential for treating or preventing bone resorption-related diseases, such as osteoporosis.

PTP1B Inhibitory and Anti-inflammatory Properties of Constituents from Eclipta prostrata L.

The white-flowered leaves of Eclipta prostrata L. together with leaves of Scoparia dulcis and Cynodon dactylon are mixedly boiled in water and given to diabetic patients resulting in the significant improvement in the management of diabetes. However, the active constituents from this plant for antidiabetic and anti-obesity properties are remaining unclear. Thus, this study was to discover anti-diabetes and anti-obesity activities through protein tyrosine phosphatases (PTP)1B inhibitory effects. We found that the fatty acids (23, 24) showed potent PTP1B inhibition with IC50 values of 2.14 and 3.21 µM, respectively. Triterpenoid-glycosides (12-15) also exhibited strong to moderate PTP1B inhibitory effects, with IC50 values ranging from 10.88 to 53.35 µM. Additionally, active compounds were investigated for their PTP1B inhibitory mechanism and docking analysis. On the other hand, the anti-inflammatory activity from our study revealed that compounds (1-4, 7, 8, 10) displayed the significant inhibition nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Especially, compound 9 showed the potent inhibitory effects in LPS-induced NO production on RAW264.7 cell. Therefore, further Western blot analysis was performed to identify the inhibitory expression including heme oxygenase-1 (HO-1) and inhibitor of kappaB (IκB) phosphorylation.

Triterpenoids from Celastrus orbiculatus Thunb. inhibit RANKL-induced osteoclast formation and bone resorption via c-Fos signaling.

Fourteen triterpenes, lup-20(29)-ene-3ß,6ß-diol (1), betulin (2), lupeol caffeate (3), 3ß-caffeoyloxylup-20(29)-en-6α-ol (4), betulin-3ß-yl-caffeate (5), 3ß-trans-feruloylbetulin (6), betulinaldehyde 3-caffeate (7), 3-O-trans-caffeoylbetulinic acid (8), dammarenediol II 3-caffeate (9), 12-oleanene-3ß,6α-diol (10), 11α-hydroxy-3ß-amyrin (11), nivadiol (12), 29-hydroxyfriedelin (13), and celastrusin A (14) were isolated from Celastrus orbiculatus Thunb. and evaluated for their activity on receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation in bone marrow macrophages (BMMs). Compounds betulin (2), betulin-3ß-yl-caffeate (5), 3ß-trans-feruloylbetulin (6), and 3-O-trans-caffeoylbetulinic acid (8) significantly inhibited osteoclast formation in a dose-dependent manner. Among these, betulin-3ß-yl-caffeate (5) exhibited the most potent inhibitory activity. We demonstrated that betulin-3ß-yl-caffeate (5) suppressed F-actin-ring formation and bone resorption activity. At the molecular level, betulin-3ß-yl-caffeate (5) inhibited RANK-induced expression of c-Fos and the induction of nuclear factor of activated T cells 1 (NFATc1), a key transcription factor for osteoclast formation, and it also downregulated mRNA expression of osteogenesis-associated marker genes including tartrate-resistant acid phosphatase (TRAP), dendritic cell-specific transmembrane protein (DC-STAMP), and matrix metalloprotein (MMP). These results indicate that betulin-3ß-yl-caffeate (5) may be a promising candidate for the treatment of osteoclast-related diseases such as osteoporosis.

Diterpenoids isolated from the root of Salvia miltiorrhiza and their anti-inflammatory activity.

Four new diterpene-type compounds normiltirone (3) and isosalviamides F-H (14-16) together with twelve known compounds (1, 2, 4-13) were isolated from the roots of Salvia miltiorrhiza. Their structures were mainly elucidated from detailed spectroscopic data. All isolated compounds were evaluated for their ability to inhibit lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages. Compound 11 showed a strong inhibitory effect, with an IC50 value of 3.4 ± 1.2 µM.

Phytochemical and pharmacological properties of Myristica fragrans Houtt.: an updated review.

Myristica fragrans Houtt. (Myristicaceae), an aromatic evergreen tree, is well known as a commercial source of mace (aril) and nutmeg (seed), which have long been widely used as spices in the culinary field. In addition, various parts of M. fragrans have been used in folk medicine for treating several diseases. Since its extensive uses in the culinary sector and folk medicine, M. fragrans has long attracted a great deal of attention from pharmacologists and chemists. Numerous studies have indicated that M. fragrans contains diverse phytochemicals such as lignans, neolignans, diphenylalkanes, phenylpropanoids, and terpenoids, which exhibit many of pharmacological activities. Among them, macelignan (1), meso-dihydroguaiaretic acid (2), myristicin (111), and malabaricone C (Mal C, 104) are the most active compounds. The aim of this review is to comprehensively summarize the phytochemical and pharmacological properties of M. fragrans that have reported to date.

Inhibition of PTP1B by farnesylated 2-arylbenzofurans isolated from Morus alba root bark: unraveling the mechanism of inhibition based on in vitro and in silico studies.

Among the 2-arylbenzofuran derivatives isolated from Morus alba, the farnesylated 2-arylbenzofuran is a rarer constituent. The derivative has been reported to exert anti-obesity effect; however, its inhibitory effect on protein tyrosine phosphatase 1B (PTP1B) has not been investigated. In the previous study, the presence of the farnesyl group in the structure of 2-arylbenzofurans was found to have positive influences on their pancreatic lipase inhibitory activity. In the present study, we have confirmed the authenticity of the notation based on the PTP1B inhibitory activity of farnesylated 2-arylbenzofurans. Specifically, two farnesylated 2-arylbenzofurans [morusalfurans B (2) and C (3)] showed strong inhibitory effects on PTP1B with IC50 values of 8.92 and 7.26 µM, respectively, which was significantly higher than that of the positive controls [sodium orthovanadate (IC50 = 15.10 µM) and ursolic acid (IC50 = 11.34 µM)]. Besides, two 2-arylbenzofurans [morusalfurans A (1) and F (6)], one flavonoid [morusalnol B (9)], and one geranylated stilbene [morusibene A (11)] exhibited PTP1B inhibition with IC50 values ranging from 11.02 to 26.56 µM. Kinetic studies revealed compounds 2, 3, 6, and 11 as mixed type PTP1B inhibitors, while 1 and 9 are known as noncompetitive. Molecular docking simulations demonstrated that these active compounds can bind with the respective catalytic or/and allosteric sites of PTP1B with negative binding energies and the results are in accordance with that of the kinetic studies. To the best of our knowledge, this is the first time, the PTP1B inhibitory activity of eleven compounds (1-11), as well as the mechanism of action underlying the effects on PTP1B enzyme of the active compounds, were investigated. In vitro and in silico results suggest that the farnesylated 2-arylbenzofurans from M. alba may potentially be utilized as an effective treatment therapy for type 2 diabetes mellitus and its associated complications.

Characterization of hydrocoptisonine metabolites in human liver microsomes using a high-resolution quadrupole-orbitrap mass spectrometer.

Hydrocoptisonine is a new compound that has been isolated from the rhizomes of Coptis chinensis, which belongs to the Ranunculaceae family of Chinese medicines. Although studies on C. chinensis have been reported, the metabolic pathway of hydrocoptisonine in human liver microsomes (HLMs) remains unelucidated. We identified 13 metabolites in HLMs, including six Phase I metabolites and seven glucuronide conjugates, using a high-resolution quadrupole-orbitrap mass spectrometer. The major metabolic pathway was the O-demethylation and mono-hydroxylation of hydrocoptisonine in HLMs. Notably, M3 metabolite was O-demethylated in dioxolane structures (cyclohexa-3,5-diene-1,2-dione), which was mediated by cytochrome P450 1A2. The locations of hydroxylation and hydroxyl-glucuronidation were identified by analyzing the signature fragments generated as a result of tandem mass spectrometry, indicating hydroxylation at an aliphatic chain or aromatic ring. We determined whether the hydroxylation and glucuronidation occurred in an aromatic moiety (M5 and M12) or an aliphatic moiety (M6 and M13), respectively, based on signature fragments of the metabolites.

Antioxidant and Antidiabetic Activities of Flavonoid Derivatives from the Outer Skins of Allium cepa L.

The onion, known as the bulb onion or common onion, is not only a key ingredient in many tasty and healthy vegetarian meals but also many traditional medicines. Nine new flavonoids [cepaflavas A, B (5, 6), cepadials A-D (7-9 and 14), and cepabiflas A-C (10-12)] and six known compounds (1-4, 13, 15) were obtained from the outer skins of Allium cepa L. Among them, compounds 5, 6, and 9 might be artificial products formed during extraction and isolation. New compounds were structurally elucidated using various spectroscopy/spectrometry techniques, including NMR and HRMS, and computational methods. Their absolute configurations were determined using time-dependent density functional theory calculations, combined with ECD spectroscopy, optical rotation calculation, and statistical procedures (CP3 and DP4 analysis). The free radical scavenging assays revealed that the new compounds 10-12 possessed considerable antioxidant activities with IC50 values of 4.25-8.88 and 7.12-8.14 µM against DPPH and ABTS•+, respectively. Compounds 13-15 showed substantial inhibitory activities against both α-glucosidase and protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 0.89-6.80 and 1.13-6.82 µM, respectively. On the basis of molecular docking studies, 13 and 15 were predicted to have high binding capacity and strong affinity toward the active site of PTP1B.

Tetra-aryl cyclobutane and stilbenes from the rhizomes of Rheum undulatum and their α-glucosidase inhibitory activity: Biological evaluation, kinetic analysis, and molecular docking simulation.

One achiral tetra-aryl cyclobutane [rheundulin A (1)] and three stilbene glycosides [rheundulins B-D (2-4)] were isolated from the methanol extract of Rheum undulatum L., along with eight known compounds (5-12). Structural determination of the new compounds (1-4) was accomplished using comprehensive spectroscopic methods. Compound 1 represents the first example of a dimeric stilbene linked via a cyclobutane ring from the Rheum genus. All isolates were screened for their inhibition against α-glucosidase. Among them, stilbene derivatives (5 and 6) showed strong inhibitory effects on α-glucosidase with IC50 values of 0.5 and 15.4 µM, respectively, which were significantly higher than that of the positive control, acarbose (IC50 = 126.8 µM). Rheundulin A (1) showed moderate α-glucosidase inhibition with an IC50 value of 80.1 µM. In addition, kinetic analysis and molecular docking simulation of the most active compound (5) with α-glucosidase were performed for the first time. Kinetic studies revealed that compound 5 competitively inhibited the active site of α-glucosidase (Ki = 0.40 µM), while 6 had a mixed-type inhibitory effect against α-glucosidase (Ki = 15.34 µM). Molecular docking simulations of 5 and 6 demonstrated negative-binding energies, indicating high proximity to the active site and tight binding to α-glucosidase enzyme.

Chemical constituents from the roots of Kadsura coccinea with their protein tyrosine phosphatase 1B and acetylcholinesterase inhibitory activities.

Kadsura coccinea (Lem.) A. C. Smith has been used as a tonic, decongestant, and digestive agent. The roots are also employed in traditional medicine to treat chronic enteritis, acute gastritis, duodenal ulcers, rheumatic pain in bone, and traumatic injuries. In the present study, we have described the biological evaluation of constituents from the roots of K. coccinea with PTP1B and AChE inhibitory activities for the first time in literature. A new compound (1), kadcoccilactone T, and 24 known ones (2‒25) were isolated and identified using spectroscopic methods. All the isolates were examined for PTP1B and AChE inhibitory activities. Compounds 4 and 8 expressed strong PTP1B inhibition with IC50 values of 1.57 ± 0.11 and 3.99 ± 1.08 µM, respectively. Apparently, these compounds were further studied for PTP1B enzyme kinetic analysis. The result indicated that compounds 4 and 8 exhibited mixed-type inhibition with the Κi values of 4.97 and 3.26 µM, respectively.

Antioxidant and anti-browning property of 2-arylbenzofuran derivatives from Morus alba Linn root bark.

Oxidation and enzymatic browning of food can affect nutritional quality, physical and chemical properties, and food safety, emphasizing the utmost importance of discovering new natural antioxidants and anti-browning agents. The present study aimed to characterize the antioxidant and anti-browning potential of 2-arylbenzofuran derivatives from the root bark of Morus alba Linn. All test compounds showed good antioxidant effects on non-enzymatic antioxidant assays. Only mulberrofuran H demonstrated potent inhibition against substrates l-tyrosine (IC50; 4.45 ± 0.55 µM) and l-DOPA (IC50; 19.70 ± 0.54 µM), indicating negative effects of the prenyl and geranyl groups in the other compounds. Molecular docking simulation predicted the involvement of an -OH group in the bulky substituent in C-11 in van der Waals interactions with copper ions (Cu400, Cu401) and peroxide ions (Per404) in the active site. Overall results characterize MH as an antioxidant and anti-browning agent, highlighting its potential role in food preservation.

6,7,4'-Trihydroxyflavone inhibits osteoclast formation and bone resorption in vitro and in vivo.

The balance between the osteoblasts and the osteoclasts is important for the maintenance of the skeleton of the human body. The osteoclasts absorb bone after differentiated into polymorphonuclear cells by the fusion of monocytes/macrophages. We have found that 6,7,4'-Trihydroxyflavone (THF), a compound from the heartwood of Dalbergia Odorifera inhibits receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation, actin ring formation, and bone resorption in RAW 264.7 cells and bone marrow macrophage. THF significantly inhibited the c-Jun-N-terminal kinase signaling pathway without affecting extracellular signal-regulated kinase, p38, and AKT signaling. Moreover, THF inhibited the expression of c-Fos, nuclear factor-activated T cells cytoplasm 1, cathepsin K, and c-src by RANKL. We used a lipopolysaccharide (LPS)-induced bone loss model in mice. Consequently, bone volume per tissue volume, trabecular number's reduction was recovered in THF-treated mice, and trabecular separation's augmentation was also attenuated by THF administration. In summary, THF inhibits RANKL-induced osteoclast differentiation by MAPK signaling pathway and inhibits bone resorption by destroying the actin ring in mature osteoclasts. THF also prevented LPS-induced bone loss in a mice model. Thus, THF may be useful in the treatment of bone diseases associated with excessive osteoclast differentiation and bone resorption.

Anti-inflammatory and cytotoxic activities of constituents isolated from the fruits of Ziziphus jujuba var. inermis Rehder.

Three new sesquilignans, zijusesquilignans A-C (1-3), together with fifteen known compounds (4-18), were isolated from fruits of Ziziphus jujuba var. inermis Rehder (Rhamnaceae). Their chemical structures were established using spectroscopic analyses including 1D- and 2D-NMR, HR-EIMS, and ECD spectra. These compounds were assessed for their inhibitory effects on nitric oxide (NO) production. Of these compounds, 1-3 and 17 displayed inhibitory effects on NO production, with IC50 values ranging from 18.1 to 66.4 µM. Pretreatment with 1 and 17 significantly suppressed LPS-induced expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein in cells. Moreover, compounds 1-3, 7, 9, and 17 exhibited cytotoxic activities against three human tumor cell lines, with IC50 values ranging from 8.4 to 44.9 µM.