Alstoscholarisine K, an Antimicrobial Indole from Gall-Induced Leaves of Alstonia scholaris

Alstoscholarisine K, an indole alkaloid with eight chiral carbons and featuring a novel 6/5/6/6/6/6/6/5 octacyclic architecture, was found to be specific to the gall-infected leaves of Alstonia scholaris. Its structure was elucidated by spectroscopy, computational analysis, and single-crystal X-ray diffraction. The unusual highly fused cage-like pyrrolo[1,2-a]pyrimidine structure with an additional -C₄N unit is possibly derived from a combination of monoterpenoid indole and polyamine pathways. The fascinating compound exhibited significant antibacterial bioactivities by targeting cell membranes.

Phytochemicals and Allelopathy of Induced Water Hyacinth against Microcystis aeruginosa

Induced water hyacinth with purple roots (PRWH) exerts a significant inhibitory effect on the growth of blue-green algae. Interestingly, its chemical constituents differ from those of wild-type water hyacinth and have not yet been reported. This study aimed to explore the chemical constituents of PRWH and its bioactive components serving as allelopathic agents against blue-green algae. Phytochemical investigation of the bioactive ethyl acetate fraction of a crude methanol extract from PRWH led to the isolation of 56 compounds, including 11 new phenylphenalene derivatives. The structures of these compounds were elucidated by comprehensive analyses through NMR, HRMS, and X-ray techniques. Bioactivity evaluation against Microcystis aeruginosa indicated that compounds 7, 12, 15, 37, 39, 45, and 47 potently inhibited blue-green algae growth.

Antioxidant and Cytoprotective Effects of New Diarylheptanoids from Rhynchanthus beesianus

Rhynchanthus beesianus (Zingiberaceae) has been an important food spice and vegetable in southern China. Fifteen phenolic compounds (1-15) including three new diarylheptanoids, rhynchanines A-C (1-3) and one new phenylpropanoid, 4-O-methylstroside B (9), were isolated from R. beesianus rhizomes. The structures of new compounds were elucidated by comprehensive analyses through NMR, HRMS technique, acid hydrolysis, and Mosher's reaction. Among them, compound 5 is the first isolated natural product and its NMR data are reported. Most of the isolated compounds, especially 3-6 and 8, showed significant antioxidant activities on DPPH, ABTS⁺ radical scavenging, and FRAP assays. Furthermore, the antioxidant phenolic compounds were evaluated for their cytoprotective capacity against H₂O₂-induced oxidative stress in HepG-2 cells. Compounds 3 and 5 could significantly inhibit reactive oxygen species production, and compounds 3, 5, and 6 could remarkably prevent the cell apoptosis. Then, the R. beesianus rhizome, which contained phenolic compounds, might serve as a functional food for potential application on preventing oxidative stress-connected diseases.

A review of plant characteristics, phytochemistry and bioactivities of the genus Glechoma

ETHNOPHARMACOLOGICAL RELEVANCE

Plants of the genus Glechoma have been abundantly used for thousands of years in China as folk treatments for cholelithiasis, urolithiasis, inflammation, and other conditions.

AIM OF THE STUDY

This review discusses the potential application of Glechoma as an herbal medicine. The plant characteristics, ethnobotanical uses, phytochemistry, and pharmacological activities of Glechoma are summarized as a guide for phytochemical and pharmacological investigations.

MATERIALS AND METHODS

Various search engines including SciFinder, Google Scholar, Scopus-Elsevier, Medline, Web of Science, and China National Knowledge Infrastructure were searched for publications on Glechoma using relevant keywords. Additionally, local records, books, and non-English journals were screened up to October 2020.

RESULTS

The phytochemistry of several Glechoma plants has been systematically studied, and over one hundred different compounds have been isolated and identified. Terpenoids, flavonoids and polyphenols are the major secondary metabolites. Crude extracts and isolated compounds have been shown to exhibit various pharmacological activities including prevention of nephrolithiasis, anti-inflammatory, analgesic, anticomplement, antimicrobial, antioxidant, depigmenting, anticancer, and antiviral activities, among others.

CONCLUSION

Glechoma species have been used as folk medicine to treat various diseases and have diverse biological activities, making them valuable starting materials for drug development. However, in most cases the pharmacological mechanisms, pharmacokinetics, toxicology, safety, and possible interactions with other drugs remain to be determined.

Bioactivity Ingredients of Chaenomeles speciosa against Microbes: Characterization by LC-MS and Activity Evaluation

Chaenomeles speciosa (Sweet) Nakai is a dual-purpose Chinese herbal medicine and functional food favored by minorities in Southwest China, and its fruits are used for the treatment of dyspepsia, dysentery, enteritis, and rheumatism inflammation. Some diseases may be related to microbial infection; however, it is not known how the fruits possess antimicrobial activity. We evaluated the antimicrobial bioctivity of different evaluation extracts of C. speciosa fruits by in vitro and in vivo with colony-forming unit assays, and the strongest bioactive-guided fraction was selected for column chromatography (CC), UHPLC-QTOF-MS/MS, and NMR spectroscopy to confirm the chemical constituents. The most possible antimicrobial mechanism of C. speciosa fruits was explored by metabolomics approach, fluorescence microscopy imaging, and scanning electron microscopy (SEM). Thirty compounds, which were major characteristic ions of the bioactive fraction, were determined precisely. The bioactive fraction could inhibit 18 pathogenic microorganisms, significantly reduced, especially drug-resistant bacteria, compared to ampicillin sodium salt, fluconazole, and berberine chloride form; and the minimum inhibitory concentration (MIC) or minimum fungicidal concentration (MFC) values were in the range of 0.1-1 mg/mL. The compounds 2'-methoxyaucuparin (1) and oleanolic acid (20) not only have antibacterial activity but also may have synergistic effects. Further, the bioactive fraction might inhibit the biofilm formation, enhance immunity, and restore bacterial infection damage in vitro and in vivo to kill microorganisms. The data indicated that C. speciosa fruits' major bioactive fraction enriched with triterpenes, flavonoids, and phenolics could be developed as a functional supplement for individuals to prevent and treat microbial infection.

Diverse isoquinolines with anti-inflammatory and analgesic bioactivities from Hypecoum erectum

ETHNOPHARMACOLOGICAL RELEVANCE

Hypecoum erectum has been used extensively in folk medicine to treat inflammation, fever, and pain. However, few investigations have been carried out on the biological activities related to its traditional use. The chemical constituents of this plant along with their anti-inflammatory and analgesic effects have yet to be revealed.

AIM OF THE STUDY

This study aimed to support the traditional use of H. erectum by first assessing its anti-inflammatory and analgesic effects and then investigating its chemical constituents to identify any anti-inflammatory and/or analgesic compounds.

MATERIAL AND METHODS

The in vivo anti-inflammatory and analgesic activities of the MeOH extract (ME), total alkaloid (AL), and non-alkaloid (Non-AL) fractions of H. erectum at doses of 200, 100, and 50 mg/kg and four major constituents (20, 21, 22, and 27) at doses of 100 and 50 mg/kg delivered via intragastrical administration were evaluated using carrageenan-induced paw edema and acetic acid-stimulated writhing animal models. A phytochemical study of the bioactive (AL) fraction was conducted using various chromatographic techniques, and the structures of the obtained isoquinolines were identified by multiple spectroscopic analyses and quantum chemical computations. Moreover, the anti-inflammatory activities of all the isolates were assessed in vitro based on the suppression of lipopolysaccharide-activated inflammatory mediators (COX-2, IL-1β, and TNF-α) in RAW 264.7 macrophage cells.

RESULTS

At the dose of 200 mg/kg, the three fractions (ME, AL, and Non-AL) of H. erectum ameliorated the paw edema by carrageenan-stimulated and reduced the number of writhing by acetic acid-induced in mice compared to the model group, with the AL fraction showing the most potent effects. Subsequent phytochemical investigation of the AL fraction led to the isolation of six new isoquinoline alkaloids (1-6) as well as 23 known analogues (7-29). However, compared to common isoquinolines, compounds 1-4 possess an additional nitrogen atom, while compound 5 has two additional nitrogen atoms. These additional atoms enrich the diversity of natural isoquinoline alkaloids. Further pharmacological evaluation in vivo revealed that the four major constituents (20, 21, 22, and 27) significantly relieved paw edema at 100 mg/kg, while protopine (20) and oxyhydrastinin (27) remarkably decreased the number of writhing at 100 mg/kg. In addition, most of the isolates displayed anti-inflammatory effects, as indicated by the inhibition of inflammatory mediators (COX-2, IL-1β, and/or TNF-α) in vitro at a treatment concentration of 5 μg/mL. trans-benzindenoazepines (13), protopine (20), and 1,3,6,6-tetramethyl-5,6,7,8-tetrahyboisoquiolin-8-one (25) showed comparable anti-inflammatory activity to dexamethasone by inhibiting the secretion of IL-1β.

CONCLUSIONS

This investigation validated the traditional use of H. erectum by assessing its anti-inflammatory and analgesic effects. Phytochemical investigation revealed the diversity and novelty of the natural isoquinoline alkaloids in H. erectum. Four major isoquinolines were identified as the bioactive constituents of H. erectum. The findings provide scientific justification to support the traditional application of H. erectum for treating inflammatory and pain disorders.

Pharmacological effects of indole alkaloids from Alstonia scholaris (L.) R. Br. on pulmonary fibrosis in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Alstonia scholaris (L.) R. Br. (Apocynaceae) is a Dai folk medicine for the treatment of lung diseases in China.

AIM OF THE STUDY

The present study investigated the anti-pulmonary fibrosis effects of total alkaloids (TA) and the potential active ingredients and its possible mechanism.

MATERIALS AND METHODS

After intratracheal instillation of bleomycin (BLM, 5 mg/kg), mice were divided into ten groups, and orally treated with the corresponding samples once daily for 28 days. The effect of indole alkaloids was determined through analysis of cytokines, as well as histopathological examinations and gene expressions.

RESULTS

Severe lung fibrosis was observed in the BLM-treated mice on day 28. However, the administration of TA significantly ameliorated the pathological changes in the lungs, decreased the content of Krebs von den Lungen-6, lactate dehydrogenase, transforming growth factor-β (TGF-β), hydroxyproline, type I collagen, and malonaldehyde, and enhanced the activity of superoxide dismutase in the serum and lung tissues. In addition, the enhanced TGF-β and matrix metalloproteinase-1 (MMP-1) expressions in BLM-induced mice were obviously weakened by indole alkaloids, as well as the ratio of matrix metalloproteinase-1 to tissue inhibitor of metalloproteinase-1 was decreased. Moreover, picrinine and scholaricine yielded markedly better values in the aforementioned indices than those in other samples, indicating that they may be the active ingredients of alkaloids.

CONCLUSIONS

TA exerted protective effects against BLM-induced pulmonary fibrosis by reducing collagen deposition through TGF-β/MMP-1 pathway.

Myrothins A-F from Endophytic Fungus Myrothecium sp. BS-31 Harbored in Panax notoginseng

Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe-microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A-F (1-6) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B (2) and E (5) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F (6) showed weak activity against F. oxysporum.

Anti-microbial Effects In Vitro and In Vivo of Alstonia scholaris

Alstonia scholaris could be used as a traditional medicinal plant in China for the treatment of acute respiratory, which might be caused by respiratory tract infections. The investigation tested the anti-infective effects of total alkaloids extract (TA) from leaves of A. scholaris, and as a result, TA inhibited herpes simplex virus type 1 (HSV-1), respiratory syncytial virus (RSV) and influenza A virus (H1N1) in vitro respectively. In addition, the survival days of mice were prolonged, and the lung weights and mortality of mice were decreased significantly, after oral administrated TA in H1N1 and beta-hemolytic streptococcus infectious models in vivo respectively. The finding supported partly the traditional usage of A. scholaris in the treatment of respiratory infections.

Mitochondrial Deoxyguanosine Kinase Regulates NAD+ Biogenesis Independent of Mitochondria Complex I Activity

Overexpression of DGUOK promotes mitochondria oxidative phosphorylation and lung adenocarcinoma progression. However, the role and mechanism of DGUOK in regulation of mitochondria function and lung cancer progression still poorly understood. Here we demonstrated that DGUOK regulated NAD⁺ biogenesis. Depletion of the DGUOK significantly decreased NAD⁺ level. Furthermore, knockout of the DGUOK considerably reduced expression of the NMNAT2, a key molecule controlling NAD⁺ synthesis, at both mRNA and protein levels. Ectopic expression of the NMNAT2 abrogated the effect of knockdown of DGUOK on NAD⁺. Notably, this regulation is independent of DGUOK -mediated mitochondria complex I activity. We also showed that NMNAT2 was highly expressed in lung adenocarcinoma and negatively correlated with the patient overall survival. Our study suggested that DGUOK regulates NAD⁺ in a NMNAT2 dependent manner and DGUOK-NMNAT2-NAD⁺ axis could be a potential therapeutic target in lung adenocarcinoma.

Structures/cytotoxicity/selectivity relationship of natural steroidal saponins against GSCs and primary mechanism of tribulosaponin A

Glioblastoma multiform (GBM) is the highly aggressive brain tumor with poor prognosis. Glioma stem cells (GSCs), small population of cancer cells that exist in GBM tissues, resistant to chemotherapy and radiotherapy and usually driving GBM recurrence, have been developed as effective therapeutic target. Steroidal saponins are one of important resources for anti-tumor agent and may be benefited to selectively clear GSCs. In this report, total of 97 natural steroidal saponins were investigated the relationship among structures/cytotoxicity/selectivity against GSCs, glioma cell lines and human untransformed cells, and revealed that tribulosaponin A was the most potent compound. Further investigation suggested that tribulosaponin A up-regulated the expression of NCF1 and NOX1 to accumulate ROS for triggering apoptosis in GSCs, but not in untransformed cells, and it was further supported by the assay that N-acetyl-l-cysteine (NAC) clearing ROS delayed GSCs apoptosis. Besides, tribulosaponin A damaged GSCs recapturing tumor spheres formation.

Total Synthesis of Dactylicapnosines A and B

Dactylicapnosines A and B, two natural products from Dactylicapnos scandens, exhibited potent anti-inflammatory and analgesic activities both in vitro and in vivo. In this paper, we report our second-generation synthesis of dactylicapnosine A and the first total synthesis of dactylicapnosine B. Our synthetic route features acid-induced isomerization of o-quinone (16), Co-mediated regioselective ring contraction of p-quinone (8b), and oxidative methoxylation of enone (18). This modified sequence provides dactylicapnosine A in 14 steps with an overall yield of 12% from a known compound (14a) and also offers opportunities to synthesize dactylicapnosine-like analogues for biological investigations.

Bioguided isolation, identification and activity evaluation of antifungal compounds from Acorus tatarinowii Schott

ETHNOPHARMACOLOGY RELEVANCE

As a traditional folk medicine, Acorus tatarinowii Schott was used to treat digestive diseases, such as diarrhea, which may be related to Candida albicans infection; however according to literature surveys, there have been few studies of A. tatarinowii focusing on its antimicrobial activity, and almost all describe investigations using crude extracts or fractions.

AIM OF THE STUDY

The aims of the current study were to isolate and identify antifungal fractions of A. tatarinowii based on their antifungal activity, explore the preliminary mechanism of 60% ethanol elution (AT60) by metabonomics, and evaluate the antifungal activity of AT60 in vivo and in vitro, to provide natural resources against fungal infections.

MATERIALS AND METHODS

As a pilot evaluation of activity, A. tatarinowii fractions and compounds with antifungal bioactivity were isolated by bioactive-guided column chromatography, and identified by LC-QTOF-MS/MS and NMR spectroscopy. The antifungal effects of the active ingredients against resistant C. albicans were evaluated by in vivo and in vitro colony forming unit assays. The mechanism underlying the activity of AT60 against C. albicans was explored using an LC-QTOF-based metabonomics approach and fluorescence microscopy imaging.

RESULTS

AT60 showed better activity against C. albicans than the same dose of the first line antifungal drugs, fluconazole and itraconazole (positive control drugs). Subsequent phytochemical investigation of AT60 identified twenty-five known compounds, six of which were isolated: asaraldehyde (7), 1-(2,4,5-trimethoxyphenyl)-1,2-propanediol (12), α-asarone (14), β-asarone (15), γ-asarone (18), acotatarone C (19). Further, the compounds α-asarone (14) and acotatarone C (19) may be responsible for the antifungal activity, and exhibit synergistic effects. Metabonomics analysis indicated that AT60 can inhibit biofilm formation by regulating the C. albicans protein kinase C pathway.

CONCLUSIONS

Our results show that A. tatarinowii has potent bioactivity against C. albicans in vitro and in vivo, and can be considered an antifungal botanic agent.

Bioassay-guided isolation of anti-inflammatory diterpenoids with highly oxygenated substituents from kidney tea (Clerodendranthus spicatus)

The whole plant of Clerodendranthus spicatus (Thunb.) is one of popular functional food in south of China, named as "kidney tea" and used to ameliorate renal inflammation. In order to verify this potential function and explore the accurate compounds responsible for inflammation, the ethanol extract, fractions, and subfractions of this plant were prepared to evaluate anti-inflammation effect on xylene-induced acute inflammatory mice model, and the results indicated that two subfractions from EtOAc fraction show potential activities. Subsequent bioassay-guided isolation of the bioactive subfractions led to isolation of 25 compounds. Among them, compounds 2, 4, 5, 9-11, 13, 16, 17, and 20-22 inhibited the productions of pro-inflammation factors TNF-α, IL-1β, and IL-8 in lipopolysaccharide (LPS) -induced renal epithelia (HK-2) cells, respectively. Further anti-inflammation evaluation in vivo indicated that the major bioactive compounds 1, 2, 5-7, 17, 21, and 22 from C. spicatus were even better than aspirin. PRACTICAL APPLICATIONS: C. spicatus as a healthy tea has been available in the Chinese market and as a medicine for various disorders such as nephritis, rheumatism, inflammation, gout, and diabetes. Previous pharmacological investigation of the plant revealed the potential anti-inflammatory activities, but the material basis of anti-inflammatory activity remains to be elucidated. In our study, the anti-inflammatory fractions and compounds were obtained by the bioassay-guide isolation and the results showed that the highly oxygenated diterpenoids were major anti-inflammatory compounds, in which 1, 2, 5-7, 17, 21, and 22 were even better than aspirin. This information supported kidney tea as a functional food for treatment of renal inflammation reasonably and may add a new dimension to biological activity of this plant in the field of agriculture as a functional food were cultivated.

Anti-inflammatory and analgesic activities of Neolamarckia cadamba and its bioactive monoterpenoid indole alkaloids

ETHNOPHARMACOLOGICAL RELEVANCE

Neolamarckia cadamba has been used traditionally to treat inflammation, fever, and pruritus in the Dai ethnopharmacy in Yunnan province, P.R. China. However, according to literature survey, the action basis of anti-inflammatory and analgesic activities of this plant were rarely reported, which accounts for the original intentions of this investigation.

AIM OF THE STUDY

The study aimed to investigate the anti-inflammatory and analgesic action of methanolic extract (ME), ethyl acetate (EA), and aqueous (AQS) fractions of N. cadamba and further explore the accurate compounds responsible for the activities of EA fraction.

MATERIALS AND METHODS

The in vivo anti-inflammatory and analgesic activities of ME, EA, and AQS fractions at the doses of 200 and 400 mg/kg and two major constituents (compounds 5 and 7) at 50 and 100 mg/kg via intragastrically administrated, respectively, were evaluated by carrageenan-induced paw edema and acetic acid-stimulated writhing animal models. Aspirin (ASP) was used as the positive control at the dose of 200 mg/kg. The monoterpenoid indole alkaloids (MIAs) in EA fraction were phytochemically studied utilizing chromatographic techniques, and their structures and absolute configurations were established on the basis of multiple spectroscopic analyses and quantum computational chemistry method. Moreover, the in vitro anti-inflammatory activities of all the isolates were assessed by suppressing releases of LPS-activated inflammatory mediators (TNF-α, IL-1β, and COX-2) in RAW 264.7 macrophage cells at a concentration of 10 μg/mL. Dexamethasone (DXM) was used as the positive control.

RESULTS

Three fractions (ME, EA, and AQS) significantly ameliorated the paw edema caused by carrageenan and reduced the number of writhing induced by acetic acid in comparison to the control group at the doses of 200 and/or 400 mg/kg (in vivo). Subsequent phytochemical investigation of EA fraction led to the structural characterization of four new monoterpenoid indole alkaloids, neocadambines A-D (1-4), as well as eight known analogues (5-12). Neocadambine A possesses a novel 14-nor-MIA skeleton that could be derived from the corynantheine-type MIAs via oxidative cleavage of C3-C14 bond and subsequently degradation of C14. Moreover, the structure of a bioactive known MIA, cadambine acid (6), was reassigned by analysis of its NMR spectroscopic data. Further biological assays revealed that the major constituent 3β-dihydrocadambine (7) significantly relieved the paw edema and decreased the number of writhing at 100 mg/kg in vivo. In addition, most of the isolates displayed remarkable in vitro anti-inflammatory effects by inhibiting the secretion of aforementioned inflammatory mediators (COX-2, IL-1β, and TNF-α) at a concentration of 10 μg/mL, and compounds 4, 7, and 9 showed better anti-inflammatory effects than that of positive control, dexamethasone.

CONCLUSIONS

This study further validated the anti-inflammatory and analgesic activities of N. cadamba, and revealed that monoterpenoid indole alkaloids could partly contribute to the efficacy of this ethnodrug. The major constituent 3β-dihydrocadambine (7) showed significant anti-inflammatory activities both in vitro and in vivo, which suggested that it could be a promising anti-inflammatory lead compound. Our findings provided scientific justification to support the traditional application of N. cadamba for treating inflammatory and nociceptive disorders.

Total alkaloids from Alstonia scholaris inhibit influenza a virus replication and lung immunopathology by regulating the innate immune response

BACKGROUND

Alstonia scholaris is a folk medicine used to treat cough, asthma and chronic obstructive pulmonary disease in China. Total alkaloids (TA) from A. scholaris exhibit anti-inflammatory properties in acute respiratory disease, which suggests their possible anti-inflammatory effect on influenza virus infection.

PURPOSE

To assess the clinical use of TA by demonstrating their anti-influenza and anti-inflammatory effects and the possible mechanism underlying the effect of TA on influenza A virus (IAV) infection in vitro and to reveal the inhibitory effect of TA on lung immunopathology caused by IAV infection.

METHODS

Antiviral and anti-inflammatory activities were assessed in Madin-Darby canine kidney (MDCK) and A549 cells and U937-derived macrophages infected with influenza A/PR/8/34 (H1N1) virus. Proinflammatory cytokine levels were measured by real-time quantitative PCR and Bio-Plex assays. The activation of innate immune signaling induced by H1N1 virus in the absence or presence of TA was detected in A549 cells by Western blot. Furthermore, mice were infected intranasally with H1N1 virus and treated with TA (50, 25 and 12.5 mg/kg/d) or oseltamivir (60 mg/kg/d) for 5 days in vivo. The survival rates and body weight were recorded, and the viral titer, proinflammatory cytokine levels, innate immune cell populations and histopathological changes in the lungs were analyzed.

RESULTS

TA significantly inhibited viral replication in A549 cells and U937-derived macrophages and markedly reduced cytokine and chemokine production at the mRNA and protein levels. Furthermore, TA blocked the activation of pattern recognition receptor (PRR)- and IFN-activated signal transduction in A549 cells. Critically, TA also increased the survival rate, reduced the viral titer, suppressed proinflammatory cytokine production and innate immune cell infiltration and improved lung histopathology in a lethal PR8 mouse model.

CONCLUSION

TA exhibits anti-viral and anti-inflammatory effects against IAV infection by interfering with PRR- and IFN-activated signal transduction.

Anti-inflammatory and antinociceptive effects of Curcuma kwangsiensis and its bioactive terpenoids in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

"Curcumae Radix", the dried rhizomes of Curcuma kwangsiensis documented in Chinese pharmacopoeia, has been traditionally used for the treatment of inflammatory and pain diseases, such as jaundice and red urine, cleaning the heart-fire and depression, arthralgia, and dysmenorrhea. However, according to literature surveys, anti-inflammatory and antinociceptive studies of C. kwangsiensis have been seldom reported so far.

AIM OF THE STUDY

The current study focuses on the anti-inflammatory and antinociceptive effects of C. kwangsiensis and discovering the bioactive compounds for its traditional usages both in vivo and in vitro, which could provide scientific justification about its traditional use.

MATERIAL AND METHODS

The anti-inflammatory and antinociceptive assays of various layers (ME, EA, AQS) from C. kwangsiensis were achieved by carrageenan-induced paw edema and acetic acid-induced writhing animal models, respectively. The most bioactive part, EA layer was further phytochemically investigated by multiple step chromatography techniques. The structures of these isolates were unambiguously elucidated by means of extensive spectroscopic and chemical methods, and comparison with corresponding data of the reported literature. Four major sesquiterpenoids (4, 6, 14, and 15) were achieved for their anti-inflammatory and antinociceptive assays by the two aforementioned animal models in vivo. All the isolated compounds were evaluated for their anti-inflammatory effects via detecting inflammatory mediator releases (COX-2, IL-1β, and TNF-α) in RAW 264.7 macrophage cells induced by LPS.

RESULTS

The ME and EA layers significantly alleviated the paw edema caused by carrageenan and decreased the number of writhes induced by acetic acid at the dose of 200 and/or 100 mg/kg in comparison to the control group (p < 0.01/0.05), and the EA layer exhibited better activity than that of ME layer. Subsequent phytochemical investigation on EA layer of C. kwangsiensis exhibited that three new terpenoid compounds (1-3), identified as (12Z,14R)-7β-hydroxylabda-8(17),12-diene-14,15,16-triol (1), (12Z,14S)- 7β-hydroxlabda-8(17),12-diene-14,15,16-triol (2), and (4S)-hydroxy-(8)-methoxy-(5S)-(H)-guaia1(10),7(11)-dien-12,8-olide (3), together with twenty-two known analogs were isolated. Furthermore, four major sesquiterpenoids (4, 6, 14, and 15) significantly relieved the paw edema and number of writhes at 100 and/or 50 mg/kg (p < 0.05/0.01). Likewise, the majority of sesqui- and diterpenoids isolated could remarkably inhibited the secretion of inflammatory mediators (COX-2, IL-1β, and TNF-α) in LPS-stimulated RAW 264.7 macrophages cells at the concentration of 20 μg/mL, comparable to DXM used as the positive control. All the results suggested that EA layer from C. kwangsiensis possessed the anti-inflammatory and antinociceptive activities, and these sesqui- and diterpenoids could be the effective constituents responsible for relieving inflammation.

CONCLUSION

The present studies undoubtedly determined the anti-inflammatory and antinociceptive material basis of C. kwangsiensis, including the EA layer and its precise components, which presented equivalent or better anti-inflammatory effects than that of positive control (ASP/DXM) in vivo and in vitro. These results not only would account for scientific knowledge for traditional use of C. kwangsiensis, but also provide credible theoretical foundation for the further development of anti-inflammatory and antinociceptive agents.

Indole alkaloids from leaves of Alstonia scholaris (L.) R. Br. protect against emphysema in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Alstonia scholaris (L.) R. Br. (Apocynaceae) is a medicinal plant in China traditionally used to treat pulmonary diseases, including bronchitis, whooping cough, asthma and chronic obstructive pulmonary disease.

AIM OF THE STUDY

To provide experimental data supporting clinical adaptation of total indole alkaloids ( TA) from A. scholaris leaves for treating emphysema.

MATERIALS AND METHODS

An emphysema model was induced by a single intratracheal instillation of porcine pancreatic elastase followed by administration of TA and four main alkaloid components (scholaricine, 19-epischolaricine, vallesamine, and picrinine) for 30 consecutive days. Cytokine levels, histopathological parameters and protein expression in lung tissues were examined.

RESULTS

Administering the TA, picrinine, scholaricine, 19-epischolaricine and vallesamine for 30 days effectively inhibited inflammatory cell accumulation and invasion in the lung tissue and relieved pulmonary tissue injury. Oxygen saturation was enhanced, and interleukin (IL)-1β, monocyte-chemo attractive peptide 1, IL-11, matrix metalloproteinase-12, transforming growth factor-β and vascular endothelial growth factor levels were significantly reduced, likely by suppressing overactivation of alveolar macrophages and pulmonary fibrosis. The elastin content was markedly elevated, and fibronectin was reduced. Bcl-2 expression was significantly increased, and nuclear factor-κB and β-catenin levels were decreased.

CONCLUSIONS

TA can be potentially used as an effective novel drug for pulmonary emphysema and exerts its effects through not only inhibiting inflammation of the airway wall and airflow resistance but also promoting lung elastic recoil and protease/anti-protease balance.

"Kidney Tea" and Its Bioactive Secondary Metabolites for Treatment of Gout

Clerodendranthus spicatus, popularly known as "kidney tea" in China, is consumed traditionally as a functional food for treatment of renal inflammation, dysuria, and gout. We evaluated the effects of C. spicatus on gout by assessing activities of antihyperuricemia, anti-gouty arthritis, and analgesia in vivo, and the results indicated that the ethyl acetate fraction shows potential activities. Subsequent phytochemical investigation of this fraction led to the isolation of 32 compounds, consisting of 20 diterpenoids (including the new orthosiphonones E and F), 2 triterpenoids, 6 flavonoids, 2 lignanoids, and 2 phenolic acid derivatives. Pharmacological investigation of the pure compounds in the cellular model of hyperuricemia indicated that 12 compounds could promote the excretion of uric acid at 10 μg/mL, and compounds 3, 4, 5, and 21 had better effects than that of benzbromarone, a famous uricosuric drug. Furthermore, compounds 4, 6, 7, 9, 14, 15, 23, 26, and 31 showed significant anti-gouty arthritis activity in monosodium urate (MSU)-induced joint swelling at the dose of 50 mg/kg, while compounds 4, 5, 7, 9, and 26 exhibited significant inhibition of pain induced by acetic acid. Our findings provided scientific justification to support the traditional application of "kidney tea" for treating gout and suggested its good application prospects in the future.

Acute and Sub-chronic Toxicity of Indole Alkaloids Extract from Leaves of Alstonia scholaris (L.) R. Br. in Beagle Dogs

Alstonia scholaris (L.) R. Br., an evergreen tropical plant rich in indole alkaloids with significant physiological activity, is traditionally used to treat respiratory diseases in China. This study was conducted to establish the toxicity profile of the alkaloid extract (TA) of A. scholaris leaves in non-rodents. After oral administration of a single dose (4 g/kg.bw), a number of transient symptoms, such as unsteady gait, drooling, emesis, and reddening of peri-oral mucosa, were observed, but no treatment-related mortality. A sub-chronic toxicity study with a range of doses of TA (20, 60 and 120 mg/kg.bw) was conducted for a 13-week treatment period, followed by 4-week recovery observation. Except for emesis and drooling in majority of animals in 120 mg/kg.bw treatment group, no clinical changes were observed in TA-treated animals. Data from electrocardiography, bone marrow, urine, fecal, hematology and clinical chemistry analyses were comparable between TA-treated and control animals. No significant differences in the relative organ weights and histopathological characteristics were evident between the TA-treated and control groups. Accordingly, the non-observed-adverse-effect-level (NOAEL) of TA was established as 120 mg/kg.bw. Our results add further knowledge to the safety database for indole alkaloid extracts from A. scholaris with potential utility as novel drug candidates.

Comparative investigation of phytochemicals among ten citrus herbs by ultra high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry and evaluation of their antioxidant properties

The citrus herbs have proved their important medicinal and nutritional values as medicine-food dual-purpose herbs, functional foods, or medical herbs in China. In this study, phytochemicals and antioxidant activity among ten typical citrus herbs (ethanol extracts) were investigated comprehensively. The major ingredients and their contents were analyzed by high-resolution mass spectrometry, and the differences of typical fragment ions between flavanone-7-O-rutinoside(s) and flavanone-7-O-neohesperidoside(s) were discriminated properly in negative electrospray ionization mode. Total polyphenols, total flavonoids, 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), and ferric reducing antioxidant power tests were performed, which indicated their beneficial values and antioxidant effects. The medicine-food dual-purpose herbs including Chenpi, Juluo, Daidaihua, Huajuhong, Xiangyuan, and Foshou exhibited antioxidant capacities significantly by decreasing intracellular reactive oxygen species intensity (P < 0.01), enhancing superoxide dismutase, catalase, and glutathione peroxidase activities (P < 0.01) in H₂ O₂ -induced RIN-m5F cells. Moreover, the functional foods Zhishi, Zhiqiao, and Qingpi showed moderate antioxidant bioactivity, while the medical herb Juhe showed weak antioxidant bioactivity, which were consistent with the multivariate analysis of their major flavonoids. The study provided a new sight for the chemical differentiation and practical application of citrus herbs as medicine-food dual-purpose herbs, functional foods, or medical herbs.