Clematomandshurica saponin E, a new triterpenoid saponin from Clematis mandshurica

Hederagenin Suppresses Inflammation and Cartilage Degradation to Ameliorate the Progression of Osteoarthritis: An In vivo and In vitro Study

Osteoarthritis (OA), a common degenerative joint disease, is characterized by the progressive degradation of articular cartilage and inflammation. Hederagenin (HE) is a pentacyclic triterpenoid saponin extracted from many herb plants. It has anti-inflammatory, anti-lipid peroxidative, anti-cancer, and neuroprotective activities. However, its effect on OA has not been investigated. Our study found that HE may be a potential anti-OA drug. In vitro, HE could suppress extracellular matrix (ECM) degradation via up-regulating aggrecan and Collagen II levels as well as downregulating MMPs and ADAMTS5 levels. It could also reduce proinflammatory and inflammatory cytokines or enzymes production, including TNF-α, IL-6, iNOS, COX-2, NO, and PGE₂. Besides, HE markedly reduced IL-1β-induced C28/I2 cell apoptosis and ROS accumulation. Mechanistically, HE exerted chondroprotective and anti-inflammatory effects by partly inhibiting JAK2/STAT3/MAPK signalling pathway and the crosstalk of the two pathways. Also, HE exhibited anti-apoptotic and anti-oxidative effect via targeting Keap1-Nrf2/HO-1/ROS/Bax/Bcl-2 axis. In vivo, HE significantly reduced monosodium iodoacetate (MIA) induced cartilage destruction of rats with a lower OARSI score and inflammatory cytokine levels, further demonstrating its protective effects in OA progression. These results suggest that HE is a potential compound for the development of drugs to treat OA.

Magnoflorine attenuates inflammatory responses in RA by regulating the PI3K/Akt/NF-κB and Keap1-Nrf2/HO-1 signalling pathways in vivo and in vitro

BACKGROUND

As a prolonged autoimmune disorder, rheumatoid arthritis (RA) is characterised by synovial hyperplasia and the erosion of bone and cartilage. Magnoflorine (MAG) is the main component purified from Clematis manshurica Rupr. Recent studies have shown that MAG has anti-inflammatory, antioxidant, and immunosuppressive effects, which are relevant to anti-RA activities.

OBJECTIVE

The current investigation was conducted to explore the anti-RA effects of MAG and to discover the possible molecular mechanisms.

METHODS

In vitro experiments, CCK-8, wound healing, and transwell assays were utilized to evaluate the anti-proliferative, anti-migratory, and anti-invasive activities of MAG, respectively. The rate of cell distribution and cell apoptosis were evaluated by flow cytometry. ROS generation was detected by DCFH-DA staining. Western blotting, quantitative real-time polymerase chain reaction assay, and immunofluorescent staining were employed to test the anti-RA effect of MAG as well as to explore the potential mechanisms by evaluating related gene and protein expression. For in vivo experiments, an adjuvant-induced arthritis (AIA) rat model was established. The related parameters were measured in rats. Then, rats were sacrificed, and ankle joints were collected for histopathological analysis and observation.

RESULTS

MAG significantly decreased the proliferation, migration, invasion, and reactive oxygen species levels in IL-1β-treated MH7A cells. Furthermore, MAG promoted cell apoptosis by increasing Bax levels and decreasing Bcl-2 levels. MAG also induced cell cycle arrest. Inflammatory cytokines (iNOS, COX-2, IL-6, and IL-8) and MMPs (MMP-1, 2, 3, 9, and 13) were reduced by MAG treatment. Molecular analysis revealed that MAG exerted anti-RA effects by partly inhibiting the PI3K/Akt/NF-κB signalling axis and activating the Keap1-Nrf2/HO-1 signalling pathway. In vivo studies have revealed that MAG treatment substantially improved severe symptoms in AIA rats, and these curative effects were linked to the attenuation of inflammatory responses.

CONCLUSION

These results first suggested that MAG exhibits anti-arthritic effects in IL-1β-treated MH7A cells and AIA rat models. Thus, MAG may be used as a new drug to treat RA clinically.

Uses, chemical compositions, pharmacological activities and toxicology of Clematidis Radix et Rhizome- a Review

ETHNOPHARMACOLOGICAL RELEVANCE

Clematis chinensis Osbeck (C. chinensis), Clematis hexapetala Pall (C. hexapetala) and Clematis terniflora var. mandshurica Rupr (C. mandshurica) are collectively referred to as Clematidis Radix et Rhizome (CRR) in China. CRR is widely distributed in China, which is used as a traditional Chinese medicine to treat rheumatic arthralgia, limb numbness, tendon constriction and inconvenience in flexion and extension.

AIMS OF THIS REVIEW

This review systematically summarized the research progress on uses, chemical components, pharmacological activities and toxicology of CRR, listed the chemical structures of main compounds for clarifying the differences in chemical compositions. Meanwhile, the review will provide a theoretical and practical basis for the further research and development of CRR.

MATERIALS AND METHODS

The available information on CRR was collected using published materials and electronic databases, including ancient and modern books, Chinese Pharmacopoeia, Ph.D. and M. Sc. dissertations, CNKI, SciFinder, WanFang data, PubMed, ScienceDirect and Web of Science. The starting and ending years of references is 1965-2020, the search strategy was conducted by key words such as uses, chemical components, pharmacology and toxicology of CRR.

RESULTS

Up to now, CRR has been used to treat various diseases/disorders, such as relieving rheumatism pain, treating cervical spondylopathy and scapulohumeral periarthritis, treating hepatic carcinoma and gastrointestinal, etc. In addition, more than 200 compounds have been isolated from the three plant species of Clematidis. Moreover, the crude extracts and isolated compounds of CRR have been reported to have a wide range of pharmacological activities, such as anti-inflammatory, anti-tumor, antimicrobial and antioxidant activities, etc. Toxicity studies have shown that CRR can cause oral burning, swelling, abdominal pain or severe diarrhea, difficulty breathing, dilated pupils, renal tissue structural changes, and severe death.

CONCLUSIONS

Researches in recent years mainly focused on C. chinensis and C. mandshurica, while there are a few reports on the pharmacological studies of C. hexapetala. Therefore, it is necessary to conduct further research on C. hexapetala. Meanwhile, it is important to pay attention to pursue research on the similarities and differences between the three plant species of Clematidis to find their respective advantages and make rational use of CRR. In addition, there is no report on the mechanism of toxicity research, which needs more attention.

Chemical constituents from rhizome of Anemone amurensis

Phytochemical investigation of the 70% EtOH extract of the rhizome of Anemone amurensis led to the isolation of two new oleanane-type triterpenoid saponins 1 and 2. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR data, and HR-ESI-MS. Compounds 1 and 2 were tested for cytotoxicities against two human cancer cell lines (A549 and Hep-G2). Compound 2 showed potent cytotoxicity with IC50 values of 38.53 and 66.17 μM, respectively, while compound 1 with IC50 > 100 μM.

Antioxidant and Anti-Inflammatory Phenolic Glycosides from Clematis tashiroi

From the 95% EtOH extract of dried aerial parts of Clematis tashiroi, eight new and four known phenolic (caffeic acid, coumaric acid, ferrulic acid) glycosides were isolated and characterized. The structures of the new isolates (clematisides A-H) were elucidated by spectroscopic data interpretation as trans-4-O-(6-O-trans-caffeoyl-β-D- glucopyranosyl)-9-O-β-D-glucopyranosyl caffeic acid (1), trans-4-O-(6-O-trans-feruloyl-β-D-glucopyranosyll)-9-O-β-D-glucopyranosyl caffeic acid (2), trans-4-O-(6-O-trans-p-coumaroyl-β-D-glucopyranosyl)-9-O-β-D-glucopyranosyl caffeic acid (3), trans-4-O-(6-O-trans-caffeoyl-β-D-glucopyranosyl)-9-O-β-D-glucopyranosyl p-coumaric acid (4), trans-3-O-(6-O-trans-caffeoyl-β-D-glucopyranosyl)-9-O-β-D-glucopyranosyl caffeic acid (5), trans-3-O-(6-O-trans-p-coumaroyl-β-D-glucopyranosyl)-9-O-β-D-glucopyranosyl caffeic acid (6), 6-(3',4'-dihydroxystyryl)-2-pyrone-4-O-(6-O-trans-caffeoyl)-β-D-glucopyranoside (7), and 6-(3',4'-dihydroxystyryl)-2-pyrone-4-O-{6-O-[4-O-(6-O-trans-caffeoyl)-β-D-glucopyranosyl]-trans-caffeoyl}-β-D-glucopyranoside (8), respectively. In a DPPH radical-scavenging test, compounds 1, 7, and 8 showed more potent antioxidant activity than that of the positive control, vitamin E. In addition, compound 7 also showed inhibitory activity in an antinitric oxide release assay.

The genus Clematis (Ranunculaceae): chemical and pharmacological perspectives

ETHNOPHARMACOLOGICAL RELEVANCE

Twenty six species of the genus Clematis (Ranunculaceae) have been traditionally used in various systems of medicine for the treatment of ailments such as nervous disorders, syphilis, gout, malaria, dysentry, rheumatism, asthma, and as analgesic, anti-inflammatory, diuretic, antitumour, antibacterial and anticancer.

AIM OF THE REVIEW

To emphasize on ethnopharmacology, chemical constituents, pharmacology, toxicology and clinical studies of various species of the genus Clematis.

MATERIALS AND METHODS

The available information on Clematis species was collected through electronic search of major scientific databases.

RESULTS

A survey of literature revealed that triterpene saponins, alkaloids, flavonoids, lignans, steroids, coumarins, macrocyclic compounds, phenolic glycosides, anemonin and volatile oils constitute major classes of chemical constituents in the genus Clematis. Preliminary analgesic, anticancer, anti-inflammatory, diuretic, antiarthritis, hepatoprotective, hypotensive and HIV-1 protease inhibitor activity studies have been carried out on crude extracts of 26 traditionally used and medicinally promising species of Clematis genus.

CONCLUSIONS

The species of the genus Clematis emerged as good source of traditional medicine for the treatment of various ailments. Although few experimental studies validated their traditional claims, but employed uncharacterized crude extracts. Such Clematis species need to be explored properly following bioactivity-directed fractionation with a view to isolate bioactive constituents, and to evaluate their possible mode of actions. These species hold great potential for detailed clinical studies so that these could be exploited as potential drugs. The review will help researchers to select medicinally potential species of Clematis genus for future research.

Triterpenoids

This review covers the isolation and structure determination of triterpenoids, including squalene derivatives, protostanes, lanostanes, holostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes and saponins; 305 references are cited.