Structural Elucidation and Cytotoxic Activity of New Monoterpenoid Indoles from Gelsemium elegans.

Two new monoterpenoid indole alkaloids, gelselegandines F (1) and G (2), were isolated from the aerial parts of Gelsemium elegans. Their structures were elucidated by means of spectroscopic techniques and quantum chemical calculations. The ECD calculations were conducted at the B3LYP/6-311G(d,p) level and NMR calculations were carried out using the Gauge-Including Atomic Orbitals (GIAO) method. Structurally, the two new compounds possessed rare, cage-like, monoterpenoid indole skeletons. All isolated compounds and the total alkaloids extract were tested for cytotoxicity against four different tumor cell lines. The total alkaloids extract of G. elegans exhibited significant antitumor activity with IC50 values ranging from 32.63 to 82.24 ug/mL. In order to discover anticancer leads from the active extraction, both new indole compounds (1-2) were then screened for cytotoxicity. Interestingly, compound 2 showed moderate cytotoxicity against K562 leukemia cells with an IC50 value of 57.02 uM.

Protective Effect of Fresh/Dry Dandelion Extracts on APAP-Overdose-Induced Acute Liver Injury.

OBJECITVIE: To compare the liver protective activity of fresh/dried dandelion extracts against acetaminophen (APAP)-induced hepatotoxicity. METHODS: Totally 90 Kunming mice were randomly divided into 10 groups according to body weight (9 mice for each group). The mice in the normal control and model (vehicle control) groups were administered sodium carboxymethyl cellulose (CMC-Na, 0.5%) only. Administration groups were pretreated with high and low-dose dry dandelion extract (1,000 or 500 g fresh herb dried and then decocted into 120 mL solution, DDE-H and DDE-L); low-, medium- and high-dose dandelion juice (250, 500, 1,000 g/120 mL, DJ-L, DJ-M, and DJ-H); fresh dandelions evaporation juice water (120 mL, DEJW); dry dandelion extract dissolved by pure water (1 kg/120 mL, DDED-PW); dry dandelion extract dissolved by DEJW (120 g/120 mL, DDED-DEJW) by oral gavage for 7 days at the dosage of 0.5 mL solution/10 g body weight; after that, except normal control group, all other groups were intraperitonealy injected with 350 mg/kg APAP to induce liver injury. Twenty hours after APAP administration, serum and liver tissue were collected and serum alanine aminotransferase (AST), aspartate transaminase (ALT), alkaline phosphatase (AKP), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) activities were quantified by biochemical kits; tumor necrosis factor (TNF-α), interleukin (IL)-2, and IL-1 ß contents in liver tissue were determined by enzyme linked immunosorbent assay kits. Histopathological changes in liver tissues were observed by hematoxylin and eosin staining; TUNEL Assay and Hoechst 33258 staining were applied for cell apoptosis evaluation. The expressions of heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor 2 (Nrf-2), caspase-9, B-cell leukemia/lymphoma 2 (Bcl-2), Bax and p-JNK were determined by Western blot analysis. RESULTS: Pretreatment with fresh dandelion juice (FDJ, including DJ-L, DJ-M, DJ-H, DEJW and DDED-DEJW) significantly decreased the levels of serum ALT, AST, AKP, TNF-α and IL-1ß compared with vehicle control group (P<0.05 or P<0.01). Additionally, compared with the vehicle control group, FDJ decreased the levels of hepatic MDA and restored GSH levels and SOD activity in livers (P<0.05 or P<0.01). FDJ inhibited the overexpression of pro-inflammatory factors including cyclooxygenase-2 and inducible nitric oxide synthase in the liver tissues (P<0.05 or P<0.01). Furthermore, Western blot analysis revealed that FDJ pretreatment inhibited activation of apoptotic signaling pathways via decreasing of Bax, and caspase-9 and JNK protein expression, and inhibited activation of JNK pathway (P<0.05 or P<0.01). Liver histopathological observation provided further evidence that FDJ pretreatment significantly inhibited APAP-induced hepatocyte necrosis, inflammatory cell infiltration and congestion. CONCLUSIONS: FDJ pretreatment protects against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway, and the effect of fresh dandelion extracts was superior to dried dandelion extracts in APAP hepatotoxicity model mice.

Effect of total alkaloids from Alstonia scholaris on airway inflammation in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Alstonia scholaris (Apocynaceae) have been traditionally used for treatment of respiratory diseases in "dai" ethnopharmacy for hundreds years, especially for cough, asthma, phlegm, chronic obstructive pulmonary disease and so on. The formulas including the leaf extract have also been prescribed in hospitals and sold over the retail pharmacies. AIM OF THE STUDY: A. scholaris is used as a traditional herbal medicine for the treatment of respiratory tract inflammation. However, there is no scientific evidence to validate the use of total alkaloids of A. scholaris in the literature. Here, we investigated the protective activity of total alkaloids (TA), extracted from the leaves of Alstonia scholaris, against lipopolysaccharide (LPS)-induced airway inflammation (AI) in rats. MATERIALS AND METHODS: 200 µg/µL LPS was instilled intratracheally in each rat, and then the modeling animals were divided into six groups (n=10, each) randomly: sham group, LPS group, Dexamethasone [1.5mg/kg, intra-gastricly (i.g.)] group, and three different doses (7.5, 15, and 30 mg/kg, i.g.) of total alkaloids-treated groups. Corresponding drugs or vehicles were orally administered once per day for 7 days consecutively. The concentration of albumin (ALB), alkaline phosphatase (AKP), lactate dehydrogenase (LDH), and the number of inflammatory cells in bronchoalveolar lavage fluid (BALF) were determined by fully automatic biochemical analyzer and blood counting instrument. Nitric oxide (NO) level, malondialdehyde (MDA) content, and superoxide dismutase (SOD) activities were examined by multiskan spectrum, and histological change in the lungs was analyzed by H.E. staining. The levels of inflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) were measured using ELISA. RESULTS: Total alkaloids decreased the percentage of neutrophil, number of WBC, levels of ALB, AKP and LDH in the BALF, while increased the content of ALB in serum. It also improved SOD activity and increased NO level in the lungs, serum and BALF, and reduced the concentration of MDA in the lungs. Total alkaloids also inhibited the production of inflammatory cytokines TNF-α and IL-8 in the BALF and lung. Finally, histopathological examination indicated that total alkaloids attenuated tissue injury of the lungs in LPS-induced AI. CONCLUSIONS: Total alkaloids have an inhibitory effect against LPS-induced airway inflammation in rats.