Identification of Dihydrobenzofuran Neolignans as Novel PDE4 Inhibitors and Evaluation of Antiatopic Dermatitis Efficacy in DNCB-Induced Mice Model.

Atopic dermatitis is a chronic relapsing skin disease characterized by recurrent, pruritic, localized eczema, while PDE4 inhibitors have been reported to be effective as antiatopic dermatitis agents. 3',4-O-dimethylcedrusin (DCN) is a natural dihydrobenzofuran neolignan isolated from Magnolia biondii with moderate potency against PDE4 (IC50 = 3.26 ± 0.28 µM) and a binding mode similar to that of apremilast, an approved PDE4 inhibitor for the treatment of psoriasis. The structure-based optimization of DCN led to the identification of 7b-1 that showed high inhibitory potency on PDE4 (IC50 = 0.17 ± 0.02 µM), good anti-TNF-α activity (EC50 = 0.19 ± 0.10 µM), remarkable selectivity profile, and good skin permeability. The topical treatment of 7b-1 resulted in the significant benefits of pharmacological intervention in a DNCB-induced atopic dermatitis-like mice model, demonstrating its potential for the development of novel antiatopic dermatitis agents.

Veronica linariifolia subsp. dilatata ameliorates LPS-induced acute lung injury by attenuating endothelial cell barrier dysfunction via EGFR/Akt/ZO-1 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: The dried aerial parts of Veronica linariifolia subsp. dilatata (Nakai & Kitag.) D.Y.Hong named Shui Man Jing (SMJ) is a traditional Chinese medicine with a long history of clinical use in the treatment of chronic bronchitis and coughing up blood, however, its role on acute lung injury (ALI) has not been revealed yet. AIM OF THE STUDY: To assess the efficiency of SMJ on ALI and to investigate whether it inhibited endothelial barrier dysfunction by regulating the EGFR/Akt/ZO-1 pathway to alleviate ALI in vivo and in vitro based on the result of network pharmacology. MATERIALS AND METHODS: An in vivo model of ALI was established using inhalation of atomized lipopolysaccharide (LPS), and the effects of SMJ on ALI were evaluated through histopathological examination and inflammatory cytokines, lung histology and edema, vascular and alveolar barrier disruption. Network pharmacology was applied to predict the mechanism of SMJ in the treatment of ALI. The crucial targets were validated by RT-PCR, Western Blotting, molecular docking, immunohistochemistry and immunofluorescence methods in vivo and in virto. RESULTS: Administration of SMJ protected mice against LPS-induced ALI, including ameliorating the histological alterations in the lung tissues, and decreasing lung edema, protein content of bronchoalveolar lavage fluid, infiltration of inflammatory cell and secretion of cytokines. SMJ exerted protective effects in ALI by inhibiting endothelial barrier dysfunction in mice and bEnd.3 cell. SMJ relieved endothelial barrier dysfunction induced by LPS through upregulating the EGFR expression. SMJ also increased the phosphorylation of Akt, and ZO-1 expression both in vivo and in vitro. CONCLUSION: SMJ attenuates vascular endothelial barrier dysfunction for LPS-induced ALI via EGFR/Akt/ZO-1 pathway, and is a promising novel therapeutic candidate for ALI.

Triterpenoids from the roots of Sanguisorba officinalis and their Nrf2 stimulation activity.

Thirteen undescribed ursane-type triterpenoids, named as sangosides A-M (1-13), including two nor-ursanes, one split ring-ursane and ten ursanes, along with thirty-six known triterpenoids (14-49) were isolated and identified from the roots of Sanguisorba officinalis (Rosaceae). Their structures and absolute configurations were elucidated through spectroscopic data, single-crystal X-ray crystallography and electronic circular dichroism analysis. Their Nrf2 activation activity was evaluated in 293 T cells in vitro. Compounds 2, 5-7, 9-13, 19, 25, 26, 28-39, 41 and 46 showed significant Nrf2 agonistic effects compared with the control group at 25 µM, their cytotoxicity and dose-effect relationship were further studied in a dose-dependent manner. Their structure-activity relationships analysis suggested that the pentacyclic triterpenoids (10, 11, 30-34 and 41) contains two pairs of double bonds on the C & E rings and the ursane-type triterpenoids (25 and 26) with a carbonyl to C-2 and a hydroxyl group at C-3 all showed a considerably Nrf2 activation activity. These results suggested that S. officinalis was worthy of further investigation to find small molecule Nrf2 activators and facilitate their utilization as natural antioxidants.

Iridoids and derivatives from Catalpa ovata with their antioxidant activities.

Six new iridoid derivatives (1-6)，together with twelve known compounds (7-18), were isolated and identified from the dried fruits of Catalpa ovata G. Don. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 2 and 3 were elucidated on the electronic circular dichroism calculations. Their antioxidant activities were evaluated by activating the Nrf2 transcriptional pathway in 293 T cells in vitro. Among them, Compounds 1, 3, 4, 6-8, 10-12, 14, 15, 17 and 18 showed significant Nrf2 agonistic effect compared with the control group at 25 µM. Finally, The hypothetical biosynthetic pathway for 1-13 was discussed.

Comprehensive quality evaluation of processed Scrophulariae Radix from different regions of China using HPLC coupled with chemometrics methods.

INTRODUCTION: Scrophulariae Radix (SR) has been extensively used in traditional Chinese medicine (TCM) for thousands of years. However, the processing methods and production areas of Scrophularia ningpoensis have undergone notable historic changes. Thus, their effects on the bioactive constituents of SR still need to be studied further. OBJECTIVES: This study aimed to establish an objective and comprehensive method to identify the correlation of bioactive constituents of SR with variety, place of origin and processing method for evaluating their qualities. METHODOLOGY: An accurate and rapid high-performance liquid chromatography-diode array detector (HPLC-DAD) method for the simultaneous determination of 11 marker components (aucubin, harpagide, 6-O-methyl-catalpol, harpagoside, verbascoside, isoverbascoside, angoroside C, cinnamic acid, l-tyrosine, l-phenylalanine, and l-tryptophan) was established to evaluate the quality of SR for the first time. In addition, the effects of different production areas and processed methods on the target compounds were studied by analysing 66 batches of SR samples with chemometrics methods, including similarity evaluation of chromatographic fingerprints of TCM, principal component analysis (PCA), and partial least squares-discriminant analysis (PLS-DA). RESULTS: Compared with "sweating", short-term "steaming" and "slice-drying" could largely preserve the bioactive constituents of SR. When using the model established through PLS-DA, five components were identified as the most significant variables for discrimination. Furthermore, the score plots of PCA and the similarity evaluation revealed that variety had a more notable influence on the quality of SR than the place of origin. CONCLUSION: An objective approach of HPLC fingerprint coupled with chemometrics analysis and quantitative assessment could be applied to discriminate different processed SR and evaluate the qualities of SR rapidly.

New furofuran and tetrahydrofuran lignans from the flower buds of Magnolia biondii Pamp and their antiallergic effects.

The dried flower buds of Magnolia biondii Pamp (herbal name, Xin-Yi) are a traditional Chinese medicine with a long history of clinical use in the treatment of allergic rhinitis and sinusitis. However, the constituents responsible for its antiallergic effects remain clearly unidentified. In the present study, totally 33 lignans were obtained from M. biondii. Among them, two novel furofuran lignans (1 and 2), two novel tetrahydrofuran lignans (3 and 4), and other 16 known lignans were isolated first time from M. biondii. The antiallergic effects of compounds 1-33 on mouse bone marrow-derived mast cells (BMMCs) degrunaliton were evaluated and results showed that compounds 7, 8, 13, 15 and 18 could significantly inhibited ß-hex release on BMMCs. The results proved that furofuran and tetrahydrofuran lignans were the main constituents in M. biondii and their antiallergic effects were related with suppressing mast cell activation.

Lignans and Phenylethanoid Glycosides from the Aerial Parts of Pogostemon cablin.

Two new lignans (1-2) and a new octaketide (12), together with twenty-nine known compounds (3-11, 13-32) were isolated and identified from the aerial part of Pogostemon cablin. Their chemical structures were revealed mainly through NMR and MS data. The absolute configuration of 1 and 2 was deduced by comparing its experimental CD with the calculated ECD spectra. The inhibitory activities of the isolated compounds on LPS-stimulated nitric oxide (NO) production in RAW 264.7 cells were investigated. At a concentration of 25 µM, compounds 1 and 11 showed approximately equal NO inhibitory effects to that of aminoguanidine.

Effect of Different Processing Methods on the Chemical Constituents of Scrophulariae Radix as Revealed by 2D NMR-Based Metabolomics.

Scrophulariae Radix (SR) is one of the oldest and most frequently used Chinese herbs for oriental medicine in China. Before clinical use, the SR should be processed using different methods after harvest, such as steaming, "sweating", and traditional fire-drying. In order to investigate the difference in chemical constituents using different processing methods, the two-dimensional (2D) 1H-13C heteronuclear single quantum correlation (1H-13C HSQC)-based metabolomics approach was applied to extensively characterize the difference in the chemical components in the extracts of SR processed using different processing methods. In total, 20 compounds were identified as potential chemical markers that changed significantly with different steaming durations. Seven compounds can be used as potential chemical markers to differentiate processing by sweating, hot-air drying, and steaming for 4 h. These findings could elucidate the change of chemical constituents of the processed SR and provide a guide for the processing. In addition, our protocol may represent a general approach to characterizing chemical compounds of traditional Chinese medicine (TCM) and therefore might be considered as a promising approach to exploring the scientific basis of traditional processing of TCM.

Eighteen structurally diversified sesquiterpenes isolated from Pogostemon cablin and their inhibitory effects on nitric oxide production.

Five new sesquiterpenes, namely, guaianes A-E (1-5), including one novel carbon skeleton guaiane-type sesquiterpene derivatives (1), together with thirteen known compounds (6-18), were isolated from the aerial parts of Pogostemon cablin (Blanco.) Benth. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 1-5 were elucidated on the base of single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations. All compounds were tested for their inhibiting effects on NO production in LPS-stimulated BV2 microglia cells as well as the cell viabilities. The results showed that compounds 2-16 and 18 possessed moderately anti-inflammatory activities at a concentration of 50 µM.

Carnosol and its analogues attenuate muscle atrophy and fat lipolysis induced by cancer cachexia.

BACKGROUND: Cancer cachexia is a multifactorial debilitating syndrome that directly accounts for more than 20% of cancer deaths while there is no effective therapeutic approach for treatment of cancer cachexia. Carnosol (CS) is a bioactive diterpene compound present in Lamiaceae spp., which has been demonstrated to have antioxidant, anti-inflammatory, and anticancer properties. But its effects on cancer cachexia and the possible mechanism remain a mystery. METHODS: The in vitro cell models of C2C12 myotube atrophy and 3T3-L1 mature adipocyte lipolysis were used to check the activities of CS and its synthesized analogues. C26 tumour-bearing BALB/c mice were applied as the animal model to examine their therapeutic effects on cancer cachexia in vivo. Levels of related signal proteins in both in vitro and in vivo experiments were examined using western blotting to study the possible mechanisms. RESULTS: Carnosol and its analogues [dimethyl-carnosol (DCS) and dimethyl-carnosol-D6 (DCSD)] alleviated myotube atrophy of C2C12 myotubes and lipolysis of 3T3-L1 adipocytes in vitro. Interestingly, CS and its analogues exhibited stronger inhibitive effects on muscle atrophy induced by tumour necrosis factor-α (TNF-α) (CS, P < 0.001; DCS, P < 0.001; DCSD, P < 0.001) in C2C12 myoblasts than on muscle atrophy induced by IL-6 (CS, P < 0.05; DCS, P = 0.08; DCSD, P < 0.05). In a C26 tumour-bearing mice model, administration of CS or its analogue DCSD significantly prevented body weight loss without affecting tumour size. At the end of the experiment, the body weight of mice treated with CS and DCSD was significantly increased by 11.09% (P < 0.01) and 11.38% (P < 0.01) compared with that of the C26 model group. CS and DCSD also improved the weight loss of epididymal adipose tissue in C26 model mice by 176.6% (P < 0.01) and 48.2% (P < 0.05) increase, respectively. CS and DCSD treatment partly preserved gastrocnemius myofibres cross-sectional area. CS treatment decreased the serum level of TNF-α (-95.02%, P < 0.01) but not IL-6 in C26 tumour-bearing mice. Inhibition on NF-κB and activation of Akt signalling pathway were involved in the ameliorating effects of CS and its analogues on muscle wasting both in vitro and in vivo. CS and its analogues also alleviated adipose tissue loss by inhibiting NF-κB and AMPK signalling pathways both in vitro and in vivo. CONCLUSIONS: CS and its analogues exhibited anticachexia effects mainly by inhibiting TNF-α/NF-κB pathway and decreasing muscle and adipose tissue loss. CS and its analogues might be promising drug candidates for the treatment of cancer cachexia.

Isatisindigoticanine A, a novel indole alkaloid with an unpresented carbon skeleton from the roots of Isatis tinctoria.

Isatisindigoticanine A (1), a new indole alkaloid with an unusual carbon skeleton of a benzofuran-3-one unit connected with a 1H-indole-3-yl unit and a 4-(1,2-dihydroxyethyl)-6-oxa-3-azabicyclo[3.1.0]hexan-2-one unit via a C-3－C-8'' bond and a C-4'－C-8'' bond, was obtained from the roots of Isatis tinctoria. Its structure was determined by physicochemical properties and spectroscopic methods including 1 D, 2 D NMR, IR, HRESIMS data. The absolutely configurations were deduced by comparison of its experimental CD and calculated ECD spectra. Nitric oxide (NO) inhibitory activities of isatisindigoticanine A was also evaluated in the LPS-stimulated RAW 264.7 cells, however, no inhibitory effect was presented.

Inhibitors of BRD4 protein from the roots of Astilbe grandis stapf ex E.H. Wilson.

A new monoterpene (1) along with eight known compounds were isolated from the roots of Astilbe grandis Stapf ex E.H. Wilson. Their structures were determined by extensive spectroscopic analysis and ECD experiments as (S)-3-(2-hydroxyethyl)-5-(2-methylprop-1-en-1-yl)furan-2(5H)-one (1), caffeic acid (2), mandelic acid (3), sonchifolinin B (4), α-viniferin (5), euscaphic acid (6), cianidanol (7), ß-sitosterol (8), and stigmasterol (9), respectively. Compounds 5 and 6 exhibited inhibitory effects against BRD4 protein with IC50 values of 13.20 and 17.39 µM, respectively. In vitro, compounds 5 and 6 showed moderate cytotoxicity to A549 cells, HCC827 cells and Hela cells with IC50 values ranging from 31.98 to 154.90 µM.

Phenols and γ-Lactams from the Aerial Part of Pseudolysimachion linariifolium subsp. dilatatum.

Linariifolioside II (1) and (2S)-2-hydroxy-5-oxoproline methyl ester (2), two new compounds along with 13 known compounds were obtained from the aerial part of Pseudolysimachion linariifolium Holub subsp. dilatatum (Nakai & Kitag.) D.Y. Hong. Their chemical structures were revealed mainly through NMR and MS data. The absolute configuration of 2 was deduced by comparing its experimental CD with the calculated ECD spectra. At a concentration of 1 mm, total antioxidant capacities of compounds 1-15 were measured using a rapid ABTS method in vitro. Compounds 1, 3-5, and 11-14 exhibited approximately equal antioxidant capacity to that of vitamin C (Vc).

Scrodentoids H and I, a Pair of Natural Epimerides from Scrophularia dentata, Inhibit Inflammation through JNK-STAT3 Axis in THP-1 Cells.

BACKGROUND: Scrophularia dentata is an important medicinal plant and used for the treatment of exanthema and fever in Traditional Tibetan Medicine. Scrodentoids H and I (SHI), a pair of epimerides of C19-norditerpenoids isolated from Scrophularia dentata, could transfer to each other in room temperature and were firstly reported in our previous work. Here, we first reported the anti-inflammatory effects of SHI on LPS-induced inflammation. PURPOSE: To evaluate the anti-inflammatory property of SHI, we investigated the effects of SHI on LPS-activated THP-1 cells. METHODS: THP-1 human macrophages were pretreated with SHI and stimulated with LPS. Proinflammatory cytokines IL-1ß and IL-6 were measured by RT-PCR and enzyme-linked immunosorbent assays (ELISA). The mechanism of action involving phosphorylation of ERK, JNK, P38, and STAT3 was measured by western Blot. The NF-κB promoter activity was evaluated by Dual-Luciferase Reporter Assay System in TNF-α stimulated 293T cells. RESULTS: SHI dose-dependently reduced the production of proinflammatory cytokines IL-1ß and IL-6. The ability of SHI to reduce production of cytokines is associated with phosphorylation depress of JNK and STAT3 rather than p38, ERK, and NF-κB promoter. CONCLUSIONS: Our experimental results indicated that anti-inflammatory effects of SHI exhibit attenuation of LPS-induced inflammation and inhibit activation through JNK/STAT3 pathway in macrophages. These results suggest that SHI might have a potential in treating inflammatory disease.

Review of the Ethnopharmacology, Phytochemistry, and Pharmacology of the Genus Veronica.

Veronica is the largest genus in the flowering plant family Plantaginaceae and comprises approximately 500 species. The genus was formerly placed in the Scrophulariaceae family, some species of which have been used in traditional medicine for the treatment of influenza, respiratory diseases, hemoptysis, laryngopharyngitis, cough, hernia, cancer, edema, and wounds. This review comprehensively summarizes the current information on the traditional uses, phytochemistry, and pharmacology of the genus Veronica on the basis of articles published from 1970 to 2018. More than 260 compounds have been isolated, and chemotaxonomic investigations of Veronica have revealed that iridoid glucosides - including aucubin, catalpol, and 6-O-catalpol derivatives - are characteristic of this genus. Modern pharmacological studies and clinical practice have demonstrated that extracts or monomeric compounds from Veronica have several pharmacological actions, such as anti-inflammatory, anti-oxidative, anticancer, antibacterial, anti-angiogenic, antineurodegenerative, neuroprotective, and hepatoprotective effects both in vivo and in vitro.

Bioactivities of Natural Catalpol Derivatives.

Catalpol, a famous molecule of iridoids, possesses extensive pharmacological activities. Our studies found that compounds with low-polarity substituents at the 6-O position of catalpol exhibited higher NF-κB inhibitory potency than catalpol. However, catalpol derivatives are not much focused. Here this review provides extensive coverage of naturally occurring catalpol derivatives discovered from 1888 until 2018. It covers their distribution, chemotaxonomic significance, chemical structures, and bioactivities from more than 200 peer-reviewed articles, and highlights the structure-activity relationship of catalpol derivatives.

Scrodentoid A Inhibits Mast Cell-Mediated Allergic Response by Blocking the Lyn-FcεRIß Interaction.

Background: Mast cells are considered an attractive therapeutic target for treating allergic diseases, and the Lyn-FcεRIß interaction is essential for mast cell activation. This study investigated the antiallergic effect of scrodentoid A (SA) on mast cells and mast cell-mediated anaphylaxis. Methods: For in vitro experiments, mast cells were treated with SA. Cell proliferation was tested using the XTT assay. The mRNA expression of various cytokines and chemokines was measured using qPCR. The levels of histamine, eicosanoids (PGD2, LTC4), and cytokines were measured using enzyme immunoassay kits. Signaling was investigated using Western blotting and immunoprecipitation. For in vivo experiments, the antiallergic activity of SA was evaluated using two mouse models of passive anaphylaxis as passive cutaneous and systemic anaphylaxis. The mechanism was investigated through immunohistochemistry and immunofluorescence. Results: SA considerably inhibited immunoglobulin (Ig) E-mediated mast cell activation, including ß-hexosaminidase release, mRNA and protein expression of various cytokines, and PGD2 and LTC4 release. Oral administration of SA effectively and dose-dependently suppressed mast cell-mediated passive cutaneous and systemic anaphylaxis. SA significantly attenuated the activation of Lyn, Syk, LAT, PLCγ, JNK, Erk1/2, and Ca2+ mobilization without Fyn, Akt, and P38 activation by blocking the Lyn-FcεRIß interaction. Conclusions: SA suppresses mast cell-mediated allergic response by blocking the Lyn-FcεRIß interaction in vitro and in vivo. SA may be a promising therapeutic agent for allergic and other mast cell-related diseases.

Neutrophil elastase inhibitory effects of pentacyclic triterpenoids from Eriobotrya japonica (loquat leaves).

ETHNOPHARMACOLOGICAL RELEVANCE: Eriobotrya japonica, a traditional herbal medicine in China and Japan, has long been used to treat chronic bronchitis and coughs. AIM OF THE STUDY: Pentacyclic triterpenoids (PTs), especially ursolic acid (UA), have been found as reversibly and competitively human neutrophil elastase (HNE) inhibitors. However, the limited solubility and poor bioavailability of PTs hinder their clinical use. Crude plant extracts may have a greater activity than isolated constituents of the equivalent dosage. In this study, an Eriobotrya japonica (loquat leaves) extract (triterpenoid composition of loquat leaves, TCLL) with enriched PTs such as UA was prepared. The study aims to compare the HNE inhibitory (HNEI) effect in vitro and the therapeutic effect on acute lung injury (ALI) in vivo between TCLL and UA. MATERIALS AND METHODS: An HNEI activity bioassay was performed with Sivelestat sodium hydrate as a positive control. A lipopolysaccharide (LPS)-induced lung inflammatory model was established to evaluate TCLL's therapeutic effect on ALI in vivo. The absorption of UA in TCLL and in UA alone was determined using a Caco-2 cell uptake model and LC-MS. RESULTS: The IC50 values of TCLL and UA for the HNEI effect were 3.26 ±â€¯0.56 µg/mL and 8.49 ±â€¯0.42 µg/mL (P < 0.01), respectively. TCLL significantly improved the inflammatory cells and inflammatory cytokine production in mice compared with the LPS group (P < 0.05). Additionally, it performed better than the UA alone group (P < 0.05). Moreover, the uptake by Caco-2 cells of UA in TCLL was higher than that in UA alone (P < 0.05). CONCLUSION: TCLL has a significant HNEI effect in vitro and a therapeutic effect on LPS-induced inflammation in a mouse model. Both the effects are more efficient than UA. Improved absorption of PTs in TCLL may be one explanation for these results.

Pharmacokinetic and metabolism studies of bavachinin through ultra-high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

Bavachinin (BVC), one of the main bioactive prenylated flavonoids derived from Psoralea corylifolia Linn, has a wide variety of pharmacological effects, such as antiangiogenic, antitumor, antiallergic, anti-inflammatory and antibacterial activities, especially as a pan-peroxisome proliferator-activated receptors agonist. A rapid and sensitive method for quantifying BVC in rat plasma was developed and validated through ultra-high-performance liquid chromatography coupled with electrospray-ionization tandem mass spectrometry. Furthermore, a complete metabolic investigation of BVC was performed through ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. In the pharmacokinetic analysis, BVC exhibited rapid oral absorption (Tmax = 0.68 ± 0.21 h), good elimination (T1/2 = 2.27 ± 1.63 h) following oral administration and poor absolute bioavailability (5.27%). Moreover, 11 metabolites of BVC in plasma, urine, bile and feces were characterized. The main metabolic pathways of BVC involved isomeriszation, glucuronidation, sulfonation, hydroxylation, methoxylation and reduction. In conclusion, the present study provides a sensitive quantitative method with a lower limit of quantification of 1 ng/mL and an improved comprehension of the physiological disposition of BVC.

Eutypenoids A-C: Novel Pimarane Diterpenoids from the Arctic Fungus Eutypella sp. D-1.

Eutypenoids A-C (1-3), pimarane diterpenoid alkaloid and two ring A rearranged pimarane diterpenoids, were isolated from the culture of Eutypella sp. D-1 obtained from high-latitude soil of the Arctic. Their structures, including absolute configurations, were authenticated on the basis of the mass spectroscopy (MS), nuclear magnetic resonance (NMR), X-ray crystallography, and electronic circular dichroism (ECD) analysis. The immunosuppressive effects of eutypenoids A-C (1-3) were studied using a ConA-induced splenocyte proliferation model, which suggested that 2 exhibited potent immunosuppressive activities.