Anti-inflammatory and analgesic monoterpenoid indole alkaloids of Kopsia officinalis

Evaluation of comparative chemical profiling and bioactivities of medicinal and non-medicinal parts of Ampelopsis delavayana

Ampelopsis delavayana, a distinctive Yi medicine, utilized the roots as an essential medicinal substance for trauma treatment of the "Yunnan Hong Yao". A. delavayana, however, cannot be cultivated artificially presently, and it has been described with a phenomenon of mixed utilization of roots and stems, impeding pharmaceutical quality control. In response to resource scarcity and standardization issues, the research comprehensively compares the material basis and efficacy of medicinal (roots) and non-medicinal (stems) parts by using chemical profiling and pharmacological methodologies. Chemical disparity between two parts was compared by TLC and HPLC. Analgesia and anti-inflammatory capabilities of both parts were comprehensively evaluated through acetic acid writhing test, hot plate test, and xylene-induced mouse ear swelling test. Additionally, all the extracts were evaluated for anti-inflammatory activities by monitoring regulation of the levels of TNF-α, IL-1β, IL-6, and IgE in ear tissue. Consequently, the findings of TLC and HPLC revealed substantial similarity in the material basis of the medicinal and non-medicinal parts of A. delavayana, and pharmacological activities of anti-inflammatory and analgesic between two parts were consistent. Different extracts remarkably reduced the levels of TNF-α, IL-1β, IL-6, and IgE, demonstrating no discernible differences. Collectively, the comprehensive exploitation indicated that the medicinal and non-medicinal parts of A. delavayana exhibited identical chemical profiling and bioactivities, providing a theoretical rationale and scientific evidence for using stems as a therapeutic part, thereby holding considerable potential for ameliorating the current status of its medicinal reserves.

Monoterpenoid indole alkaloid dimers from the Melodinus axillaris induce G2/M phase arrest and apoptosis via p38 MAPK activation in HCT116 cells

Four monoterpenoid indole alkaloid dimers (MIADs), axidimins A-D (1-4), which possesses unprecedented apidosperma-aspidosperma-type skeletons, along with twelve known MIAs were isolated from Melodinus axillaris. Their structures were established by comprehensive analysis of the HRESIMS, NMR, ECD calculation and DP4 + analysis. A possible biosynthetic pathway for axidimins A-D was proposed. In vitro, axidimins C and D exhibited significant cytotoxicities against HCT116 cells with IC50 values of 5.3 μM and 3.9 μM, respectively. The results obtained from flow cytometry and Western blot analysis clearly demonstrated that axidimins C and D significantly induced a reverse G2/M phase arrest and apoptosis of HCT116 cells. The potential mechanism of axidimins C and D on HCT116 cells were thoroughly discussed through the utilization of network pharmacology and molecular docking research. Subsequently, the selected targets were validated using Western blot and CETSA analysis, confirming that axidimins C and D exert its cytotoxic effects through the activation of the p38 MAPK pathway, ultimately leading to HCT116 cells death. This study provides evidence indicating that axidimins C and D have the potential to induce cell cycle arrest and apoptosis in HCT116 cells by modulating the p38 MAPK signaling pathway. These findings offer a novel perspective for the development of anti-colorectal cancer drugs.

Ormosianines A-P, Structurally Diverse Quinolizidine Alkaloids with AChE Inhibitory Effects from Ormosia yunnanensis

Sixteen new quinolizidine alkaloids (QAs), named ormosianines A-P (1-16), and 18 known congeners (17-34) were isolated from the stems and leaves of Ormosia yunnanensis. The structures were elucidated based on spectroscopic analyses and electron circular dichroism (ECD) calculations. Structurally, ormosianines A (1) and B (2) are the first examples of cytisine and Ormosia-type alkaloids with the cleavage of the piperidine ring. Results of the acetylcholinesterase (AChE) inhibitory assay revealed that the pentacycline Ormosia-type QAs, including 1, 16, 24, and 27-29, are good AChE inhibitors. Ormosianine A (1) exhibited more potent AChE inhibitory activity with an IC50 value of 1.55 μM. Molecular docking revealed that 1 might bind to the protein 1DX4, forming two hydrogen bonds with residues SER-238 and HIS-480.

The Protective Effect of (-)-Tetrahydroalstonine against OGD/R-Induced Neuronal Injury via Autophagy Regulation

Here, (-)-Tetrahydroalstonine (THA) was isolated from Alstonia scholaris and investigated for its neuroprotective effect towards oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced neuronal damage. In this study, primary cortical neurons were pre-treated with THA and then subjected to OGD/R induction. The cell viability was tested by the MTT assay, and the states of the autophagy-lysosomal pathway and Akt/mTOR pathway were monitored by Western blot analysis. The findings suggested that THA administration increased the cell viability of OGD/R-induced cortical neurons. Autophagic activity and lysosomal dysfunction were found at the early stage of OGD/R, which were significantly ameliorated by THA treatment. Meanwhile, the protective effect of THA was significantly reversed by the lysosome inhibitor. Additionally, THA significantly activated the Akt/mTOR pathway, which was suppressed after OGD/R induction. In summary, THA exhibited promising protective effects against OGD/R-induced neuronal injury by autophagy regulation through the Akt/mTOR pathway.

Dimeric benzylisoquinoline alkaloids from Thalictrum delavayi and their biological activities

A phytochemical investigation of the whole plants of T. delavayi led to the isolation of five new dimeric benzylisoquinoline alkaloids, thalidelavines A-E (1-5), together with six known congeners (6-11). The structures and absolute configurations of new compounds were established based on analyses of spectroscopic data, ECD calculations, and single crystal X-ray crystallography. Thalidelavines A-E (1-5) were structurally complex bisbenzylisoquinoline alkaloids with various configurations. These isolated alkaloids were evaluated for their cytotoxic and immunosuppressive effects. Among them, both 9 and 10 displayed significant cytotoxicities against T98G cell lines with an IC₅₀ value of 2.1 μM, compared with the positive CPT-11 (IC₅₀ = 3.0 μM). In addition, 5-7 showed remarkable immunosuppressive effects. These findings not only enrich the structural diversity of bisbenzylisoquinoline alkaloids, but also provide potential candidates for the further development of the antitumor and immunosuppressive agents.

Monoterpenoid indole alkaloid dimers from Kopsia arborea inhibit cyclin-dependent kinase 5 and tau phosphorylation

Three undescribed monoterpenoid indole alkaloid dimers (kopoffines A-C, which are connected via a methylene unit) and with nine known alkaloids were isolated and identified from the fruits of Kopsia arborea Blume. Their structures, including their absolute configurations, were established by HRESIMS, NMR, single-crystal X-ray diffraction, and ECD analyses. Kopoffines A-C showed significant inhibition against cyclin-dependent kinase 5 (IC₅₀: 0.34-2.18 μM). Western blotting analyses showed that kopoffines A-C significantly decreased the protein levels of CDK5 and phospho-CDK5 (Tyr15) (pCDK5) at concentrations of 2.5 and 10 μM. The levels of phospho-Tau (Thr217) (pTau217, a new biomarker of AD), and phospho-Tau (Ser396) (pTau396), which play major roles in the formation of neurofibrillary tangles , were decreased by the kopoffines A-C treatment. Molecular docking studies indicated that kopoffines A-C could form stable interactions with CDK5.

New steroidal alkaloids with anti-inflammatory and analgesic effects from Veratrum grandiflorum

ETHNOPHARMACOLOGICAL RELEVANCE

"Li-Lu", the roots and rhizomes of Veratrum grandiflorum (Melianthiaceae), has been historically used as a traditional folk medicine for the treatment of wrist pain, fractures, sores, and inflammation in Yunnan Province, China. However, the anti-inflammatory and analgesic studies of this plant have seldom reported.

AIM OF THE STUDY

To evaluate the anti-inflammatory and analgesic properties related to the traditional usage of V. grandiflorum both in vitro and in vivo, and further explore the accurate bioactive compounds from the medicinal plant.

MATERIALS AND METHODS

Phytochemical investigation was carried out by chromatographic methods and their structures were established based on extensive spectra and comparison with corresponding data in the reported literatures. Anti-inflammatory activities were assessed by the suppression of lipopolysaccharide-activated inflammatory mediators in RAW 264.7 macrophage cells in vitro. Furthermore, anti-inflammatory and analgesic effects were evaluated based on carrageenan-induced paw edema and acetic acid-stimulated writhing in mice.

RESULTS

The methanol extract (ME) of V. grandiflorum significantly alleviated the paw edema caused by carrageenan and the writhing numbers induced by acetic acid. Subsequent phytochemical investigation led to isolated of 21 steroidal alkaloids, including seven new compounds, veragranines C-I (1-7). Anti-inflammatory test indicated that steroidal alkaloids could decrease the expression of cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells at a concentration of 5.0 μg/ml in vitro, comparable to DXM. Moreover, five new steroidal alkaloids (2, 4, 5, 6, and 7) and two major steroidal alkaloids (9 and 13) significantly decreased the numbers of writhing in mice at the doses of 0.5 and/or 1.0 mg/kg (p < 0.01/0.05), roughly comparable to Dolantin™ at 10.0 mg/kg.

CONCLUSIONS

The investigation supported the traditional use of V. grandiflorum and provided new steroidal alkaloids as potent analgesic agents.