Comparison of Differences in Chemical Composition and Related Antioxidant Activity of Snow Lotus from Different Origins.

The snow lotus is an endangered traditional Chinese medicinal herb. Saussurea involucrata, Saussurea laniceps, and Saussurea medusa, the three main snow lotus species (five herbs and two S. involucrata cell cultures), were selected for this study. Snow lotus (XLs) was extracted using 75 % (v/v) ethanol. Two reversed phase-high performance liquid chromatography-diode array detector methods were developed and validated for the determination of 10 representative components in XLs. The antioxidant efficacy of XLs and their components was investigated using DPPH, ABTS free radical scavenging, and ROS inhibition experiments. The results showed that the IC50 for DPPH scavenging ranged from 0.06-0.29 mg/mL for XLs and from 0.13-0.63 mg/mL for ABTS, and could downregulate ROS to varying degrees. The results of the antioxidant activity showed that rutin, quercetin, and isochlorogenic acid A contributed to the antioxidant capacity of XLs. The high content and activity of the cell cultures indicate that they can serve as an effective alternative to snow lotus, thus providing a theoretical basis for the selection of herbs and cell cultures to fulfil various needs.

Umbelliferone and scopoletin target tyrosine kinases on fibroblast-like synoviocytes to block NF-κB signaling to combat rheumatoid arthritis.

Rheumatoid arthritis (RA) is a complex autoimmune condition primarily affecting synovial joints, which targeted synthetic drugs have damaging safety issues. Saussurea laniceps, a reputed anti-rheumatic medicinal herb, is an excellent place to start looking for natural products as safe, effective, targeted therapeutics for RA. Via biomimetic ultrafiltration, umbelliferone and scopoletin were screened as two anti-rheumatic candidates with the highest specific affinities towards the membrane proteomes of rheumatic fibroblast-like synoviocytes (FLS), the pivotal effector cells in RA. In vitro assays confirmed that the two compounds, to varying extents, inhibited RA-FLS proliferation, migration, invasion, and NF-κB signaling. Network pharmacology analysis and molecular docking analysis jointly revealed that umbelliferone and scopoletin act on multiple targets, mostly tyrosine kinases, in combating RA. Taken together, our present study identified umbelliferone and scopoletin as two major anti-rheumatic components from SL that may bind and inhibit tyrosine kinases and subsequently inactivate NF-κB in RA-FLSs. Our integrated drug discovery strategy could be valuable in finding other multi-target bioactive compounds from complex matrices for treating multifactorial diseases.

Selection and Validation of Reference Genes for RT-qPCR Analysis in Tibetan Medicinal Plant Saussurea Laniceps Callus under Abiotic Stresses and Hormone Treatments.

Real-time quantitative PCR (RT-qPCR) is an important technique for studying gene expression analysis, but accurate and reliable results depend on the use of a stable reference gene. This study proposes to test the expression stability of candidate reference genes in the callus of Saussurea laniceps, a unique Tibetan medicinal plant. Based on the S. laniceps callus transcriptome, eleven candidate reference genes, including TUA2, TUB3, TUB8, TIF3B1, TIF3H1, ELF5A, PP2AA2, UEV1D, UBL5, UBC36, and SKIP1), were validated for RT-qPCR normalization in the callus under abiotic stress (salt, cold, and UV) and hormone treatments (abscisic acid, MeJA, and salicylic acid). The stability of the candidate genes was evaluated in all the samples of S. laniceps. Comprehensive analysis of all samples showed that the best reference genes were UBC36 and UBL5. ELF5A and TIF3B1 were ranked as the most stable genes in the sample sets under abiotic stress. For hormone stimulation, UBC36 and TIF3H1 genes had the best stability. This study provides useful guidelines and a starting point for reference gene selection for expression analysis using RT-qPCR techniques in S. laniceps.

A hybrid platform featuring nanomagnetic ligand fishing for discovering COX-2 selective inhibitors from aerial part of Saussurea laniceps Hand.-Mazz.

ETHNOPHARMACOLOGICAL RELEVANCE: Saussurea laniceps Hand.-Mazz. (Compositae) is a representative "snow lotus" herb well known in Chinese folk medicine to treat inflammation-related diseases such as arthritis. S. laniceps (SL) shows anti-inflammatory and analgesic potencies and contains various constituents potentially with cyclooxygenase-2 (COX-2) selective inhibition. The herb is a valuable source of natural alternatives to synthetic COX-2 selective nonsteroidal anti-inflammatory drugs, a common medication for rheumatoid arthritis (RA) and osteoarthritis (OA) reported with serious cardiovascular side effects. AIM OF THE STUDY: Based on an innovative drug screening platform, this study aimed to discover safe, effective COX-2 selective inhibitors from SL. MATERIALS AND METHODS: An enzyme-anchored nanomagnetic fishing assay was developed to separate COX-2 ligands from SL. Cell and animal models of cardiomyocytes, lipopolysaccharide-stimulated macrophages, rat adjuvant-induced arthritis, and anterior cruciate ligament transection-induced OA rats, were adopted to screen the single/combined ligands regarding toxicity and bioactivity levels. Molecular docking was employed to unravel binding mechanisms of the ligands towards COX-1 and COX-2. RESULTS: Four COX-2 selective compounds were separated from SL using optimized COX-2-functionalized magnetic nanoparticles. All the four ligands were proved with evidently lower cardiotoxicity both in vitro and in vivo than celecoxib, a known COX-2 selective inhibitor. Two ligands, scopoletin and syringin, exhibited potent anti-arthritic activities in rat models of RA and OA by alleviating clinical statuses, immune responses, and joint pathological features; their optimum combination ratio was discovered with stronger remedial effects on rat OA than single administrations. The COX-1/2 binding modes of the two phytochemicals contributed to explain their cardiac safety and therapeutic performances. CONCLUSIONS: The screened chemicals are promising to be developed as COX-2 selective inhibitors as part of treating RA and OA. The hybrid strategy for discovering therapeutic agents from SL is shown here to be efficient; it should be equally valuable for finding other active chemicals in other natural sources.

Structural Elucidation of a Novel Pectin-Polysaccharide from the Petal of Saussurea laniceps and the Mechanism of its Anti-HBV Activity.

A novel polysaccharide designated SLP-4 with the Mw of 19681 Da was purified from the petal of Saussurea laniceps. Monosaccharide composition analysis indicated that SLP-4 was composed of mannose, rhamnose, galacturonic acid, glucose, galactose, xylose and arabinose in a molar ratio of 0.825:2.030:14.998:0.841:8.260:4.039:6.009. Structural features indicated that SLP-4 was a typical pectin polysaccharide with a backbone containing →3,6)-Galp-(1→, →4)-GalpA-(1→, →6)-Galp-(1→, →4, 6)-Galp-(1→ and →2, 4)-Rhap-(1→ with the branches of →4)-Galp-(1→, T-Galp-(1→, →3)-Galp-(1→, T-Rhap-(1→, T-Araf-(1→, →5)-Araf-(1→, T-Glcp-(1→, →4)-Xylp-(1→ and →4)-Manp-(1→. Additionally, SLP-4 could effectively inhibit the secretion of HBsAg and HBeAg in HepG2.2.15 cells, but had little effect on the replication of HBV DNA. This inhibition didn't involve cellular pathways, and was due to the interaction between SLP-4 and HBsAg or HBeAg, which may block the ELISA detection of HBsAg and HBeAg. The present study may provide useful information for further study of SLP-4 and understanding of anti-HBV activity of polysaccharides.

An integrated strategy based on UPLC-DAD-QTOF-MS for metabolism and pharmacokinetic studies of herbal medicines: Tibetan "Snow Lotus" herb (Saussurea laniceps), a case study.

ETHNOPHARMACOLOGICAL RELEVANCE: Saussurea laniceps Hand.-Mazz. (SL) has long been used under the herbal name Tibetan "Snow Lotus" for the treatment of rheumatoid arthritis, stomachache and dysmenorrhea in Tibetan folk medicine. Since herbal medicine (HM) is a synergistical system with multiple components, both of the metabolism and pharmacokinetic studies of HM are interdependent. This study aimed to develop an integrated strategy based on the UPLC-DAD-QTOF-MS technique for metabolism and pharmacokinetic studies of HM. MATERIAL AND METHODS: SL was used here as a test herb to verify the feasibility of the proposed strategy. SL was administered to rats, then, the blood plasma, urine and feces were analyzed to determine the metabolic profiles. Using our strategy, umbelliferone and scopoletin were evaluated to be the key bioactive components. Their pharmacokinetic parameters were measured and biotransformation pathways were elucidated. RESULTS: After oral administration of SL to rats, 17 components in blood, 10 components in urine and 2 components in feces were identified and characterized using our UPLC-DAD-QTOF-MS method. Umbelliferone, scopoletin and their metabolites were found to be the major components involved in the metabolism process. Literature reports also suggest that umbelliferone and scopoletin are responsible for the therapeutic effects of SL, thus these two components were selected as the active markers for pharmacokinetic study. In the test of validity, the established method presented good linearity with R(2)>0.99. The relative standard deviation value was below 13.9% for precision, and recovery studies for accuracy were found to be within the range 91.8-112.5%. CONCLUSION: The present strategy offers, simultaneously, precision in quantitative analysis (metabolism study) and accuracy in quantitative analysis (pharmacokinetic study) with greater efficiency and less costs, which is therefore reliably used for integrated metabolism and pharmacokinetic studies of HM.