Chemical constituents from Stauntonia brachyanthera Hand–Mazz

Study of Anti-Inflammatory and Analgesic Activity of Scorpion Toxins DKK-SP1/2 from Scorpion Buthus martensii Karsch (BmK)

Buthus martensii Karsch (BmK), is a kind of traditional Chinese medicine, which has been used for a long history for the treatment of many diseases, such as inflammation, pain and cancer. In this study, DKK-SP1/2/3 genes were screened and extracted from the cDNA library of BmK. The DKK-SP1/2/3 were expressed by using plasmid pSYPU-1b in E. coli BL21, and recombinant proteins were obtained by column chromatography. In the xylene-induced mouse ear swelling and carrageenan-induced rat paw swelling model, DKK-SP1 exerted a significant anti-inflammatory effect by inhibiting the expression of Nav1.8 channel. Meanwhile, the release of pro-inflammatory cytokines (COX-2, IL-6) was decreased significantly and the release of anti-inflammatory cytokines (IL-10) were elevated significantly. Moreover, DKK-SP1 could significantly decrease the Nav1.8 current in acutely isolated rat DRG neurons. In the acetic acid-writhing and ION-CCI model, DKK-SP2 displayed significant analgesic activity by inhibiting the expression of the Nav1.7 channel. Moreover, DKK-SP2 could significantly inhibit the Nav1.7 current in the hNav1.7-CHO cells.

Anti-Nociceptive and Anti-Inflammation Effect Mechanisms of Mutants of Syb-prII, a Recombinant Neurotoxic Polypeptide

Syb-prII, a recombinant neurotoxic polypeptide, has analgesic effects with medicinal value. Previous experiments indicated that Syb-prII displayed strong analgesic activities. Therefore, a series of in vivo and vitro experiments were designed to investigate the analgesic and anti-inflammatory properties and possible mechanisms of Syb-prII. The results showed that administered Syb-prII-1 and Syb-prII-2 (0.5, 1, 2.0 mg/kg, i.v.) to mice significantly reduced the time of licking, biting, or flicking of paws in two phases in formalin-induced inflammatory nociception. Syb-prII-1 inhibited xylene-induced auricular swelling in a dose-dependent manner. The inhibitory effect of 2.0 mg/kg Syb-prII-1 on the ear swelling model was comparable to that of 200 mg/kg aspirin. In addition, the ELISA and Western blot analysis suggested that Syb-prII-1 and Syb-prII-2 may exert an analgesic effect by inhibiting the expression of Nav1.8 and the phosphorylation of ERK, JNK, and P38. Syb-prII-1 markedly suppressed the expression of IL-1β, IL-6, and TNF-α of mice in formalin-induced inflammatory nociception. We used the patch-clamp technique and investigated the effect of Syb-prII-1 on TTX-resistant sodium channel currents in acutely isolated rat DRG neurons. The results showed that Syb-prII-1 can significantly down regulate TTX-resistant sodium channel currents. In conclusion, Syb-prII mutants may alleviate inflammatory pain by significantly inhibiting the expression of Nav1.8, mediated by the phosphorylation of MAPKs and significant inhibition of TTX-resistant sodium channel currents.

The analgesic activities of Stauntonia brachyanthera and YM11 through regulating inflammatory mediators and directly controlling the sodium channel prompt

The analgesic studies on Stauntonia brachyanthera, a traditional Chinese folk medicine used to treat headache, pains and inflammatory diseases in local areas, showed that the EtOH extracts (EESB) and the characteristic ingredient YM₁₁ could significantly inhibit the acetic acid-induced writhing responses by 43.1% and 78.95%, and decrease the xylene-induced ear edemas by 48.9% and 21.4%, respectively. EESB could significantly increase pain threshold of mice in hot-plate test, but the effect of YM₁₁ was not obviously. Further study in formalin test showed the inhibitory effect of YM₁₁ in 2^nd phase was more significant than that in 1^st phase, revealed the peripheral analgesic activity of YM₁₁. The ELISA and Western Blot analysis suggested that the analgesic mechanisms of YM₁₁ were related to the inhibitions of the expressions of TNF-α, IL-1β and IL-6, and down-regulations of Na_v1.8 protein in the left side of L4–6 DRG regulated by MAPKs, in which the levels of p-ERK, p-JNK and p-p38 were all decreased. In addition, the electrophysiological experiments indicated YM₁₁ could reduce the Nav1.8 currents by 46.01% in small-diameter DRG neurons. Therefore, the analgesic activity of S. brachyanthera might be based on the regulation of inflammatory mediators and the directly control of the sodium channel prompt.

Potential anti-gout constituents as xanthine oxidase inhibitor from the fruits of Stauntonia brachyanthera

With the aim of finding a better xanthine oxidase inhibitor with potential anti-gout properties, the studies on the fruit of Stauntonia brachyanthera were carried out, which led to the isolation of 12 glycosides, including 4 new nor-oleanane triterpenoids. Their structures were determined by comprehensive spectroscopic (NMR and HR MS) analysis. Two compounds (4 and 11) exhibited significant inhibitory activities on xanthine oxidase with IC₅₀ values of 5.22 and 1.60µM, respectively. Another five compounds (1, 2, 3, 8 and 10) showed qualified activities. The results suggested that the existences of nor-oleanane triterpenoids and flavonoids in the fruits were responsible for the inhibitory activity on xanthine oxidase that could cut off the production of uric acid. Nor-oleanane triterpenoids, a new leading XO inhibitor, is worthy of further studies on molecular biology level for its mechanisms.

Brachyantheraoside A8, a new natural nor-oleanane triterpenoid as a kidney-type glutaminase inhibitor fromStauntonia brachyanthera

With the aim of finding a better kidney-type glutaminase (KGA) inhibitor with potential anti-cancer properties, 18 nor-oleanane triterpenoids fromStauntonia brachyanthera, including 2 new ones, were screened against KGA.

The inhibitory effects of nor-oleanane triterpenoid saponins from Stauntonia brachyanthera towards UDP-glucuronosyltransferases

The inhibition of UDP-glucuronosyltransferases (UGTs) by herbal components might be an important reason for clinical herb-drug interaction (HDI). The inhibitory effects on UGTs via nor-oleanane triterpenoid saponins, which were the bioactive ingredients from Stauntonia brachyanthera, a traditional Chinese folk medicines with highly biological values, were evaluated comprehensively with recombinant UGT isoforms as enzyme source and a nonspecific substrate 4-methylumbelliferone (4-MU) as substrate. The results showed that there are seven compounds, 2, 3, 4, 8, 9, 13 and 14, respectively, exhibited potential inhibitions towards UGT1A1, UGT1A3 and UGT1A10 among all 23 compounds isolated from the plants. The IC50 values were 17.1μM, 13.5μM, 9.5μM, 15.7μM, 16.3μM, 1.1μM, and 0.3μM, respectively. Data fitting using Dixon and Lineweaver-Burk plots demonstrated that the inhibition of UGT1A10, UGT1A1 and UGT1A3 was best fit to noncompetitive type and competitive, respectively. The inhibition kinetic parameter (Ki) was calculated to be 39μM, 17μM, 3.3μM, 10μM, 9.3μM, 0.19μM, and 0.016μM, respectively. All these experimental data suggested that HDI might occur when compounds containing herbs were co-administered with drugs which mainly undergo UGTs-mediated metabolism.

Diuretic Properties and Chemical Constituent Studies on Stauntonia brachyanthera

The pharmacological evaluation demonstrated that the extracts from the stem of S. brachyanthera could significantly increase the outputs of urine of rats compared to those of furosemide treated group, and the effect could last for a longer period of time. The best effect appeared in the first two hours, which scientifically confirmed the diuretic effect of the plant. The comparative pharmacognosy study showed that the characters of the crude drugs of the stem of S. brachyanthera were similar to those of Akebia caulis. Further systemic work on its chemical constituents by chromatographic methods and NMR elucidations led to the isolation of 10 triterpenoids, 6 flavonoids, 4 lignanoids, and 3 phenylethanoid glycosides, whose structural types were much similar to those of A. quinata. Among them, 7 compounds were firstly reported in the genus of Stauntonia and calceolarioside B was the common characteristic constituent in both plants. From the similar pharmacognosy characters, pharmacological effects, and chemical constituents, it could be concluded that S. brachyanthera have a great possibility to be a succedaneum of Akebia caulis, whose supply is extremely short in recent years.