Expression of IL-17A and IL-17F in lipopolysaccharide-induced acute lung injury and the counteraction of anisodamine or methylprednisolone

Th17 cytokines IL-17A and IL-17F as pro-inflammatory cytokines played an important role in triggering inflammatory responses. However, little was known about the expression of IL-17A and IL-17F in acute lung injury (ALI). Therefore, the present study investigated the expression of IL-17A and IL-17F in lipopolysaccharide (LPS)-induced ALI in rats and rat pulmonary microvascular endothelial cells (PMVEC) by enzyme-linked immunosorbant assay or reverse transcription-polymerase chains reaction. Anisodamine and methylprednisolone were also investigated as anti-inflammatory strategy in the process of LPS-induced ALI. Lung injury was evaluated by histological changes, right lung wet weight:body weight (LW/BW) ratios, and protein education and total leukocyte count of bronchoalveolar lavage fluid (BALF). Our findings showed that LPS exposure elevated the levels of leukocyte number, protein education in BALF and the ratios of LW/BW, increased the expression of IL-17A and IL-17F in the lung tissues homogenate, BALF and serum of ALI rats. Up-regulation of IL-17F expression was also observed after LPS challenge in rat PMVEC. Treatment with anisodamine or methylprednisolone significantly inhibited the increases of parameters of ALI induced by LPS, and markedly reduced the expression of IL-17A and IL-17F in rats and the IL-17F expression in PMVEC. These data suggested that IL-17A and IL-17F maybe play an important role in LPS-induced ALI via autocrine and paracrine mechanisms, and anisodamine is similar in extent to methylprednisolone that contributes to relieve LPS-induced ALI.

Solasodine rhamnosyl glycosides cause apoptosis in cancer cells. Do they also prime the immune system resulting in long-term protection against cancer?

Solasodine rhamnosyl glycosides (SRGs) induce apoptosis in a wide variety of cancer cells and are more effective than many well-established anticancer agents. Combination therapy of SRGs with cisplatin treats cisplatin-resistant cells such as lung cancer and breast cancer cells. Anticancer therapies with SRGs have been used intravenously, intraperitoneally, intralesionally, orally, and topically. Data is now presented that in addition to apoptosis and, perhaps as a consequence thereof, SRGs also have an effect of stimulating lasting immunity against cancer as shown with a mouse model and the terminal cancer Sarcoma 180. Mice were inoculated i. p. with Sarcoma 180. Groups of animals were administered SRGs half an hour after Sarcoma 180 inoculation. Mice treated with Sarcoma 180 but not with SRGs all died within 20 days. Four doses of SRGs caused total remission of Sarcoma 180 activity. Mice that went into remission were then reinoculated 20 days later with the cancer. Ten of twelve SRGs cured-animals were resistant to reinduction of terminal doses of the cancer. In comparison, twelve of twelve mice treated with SRGs without initial Sarcoma 180 activity but which were inoculated with Sarcoma 180 cells 20 days later, all died. In addition to apoptosis, SRGs stimulate lasting immunity against cancer. SRGs could play an important role in clinical management of diseases such a malignancy and also be used as a preventative therapy.

Synthesis of solasodine glycoside derivatives and evaluation of their cytotoxic effects on human cancer cells

Solasodine glycosides, such as solamargine, have been proved to be very important anti-cancer agents. In order to discover more potent cytotoxic agents and explore the preliminary structure activity relationship, a new series of solasodine glycosides 2-9 were synthesized via a transglycosylation strategy, and their cytotoxic activity against a panel of human cancer cell lines (MCF-7, KB, K562, and PC3 cells) were evaluated by MTT assays. The results indicated that compounds 2, 8, and 9 with the substitute moiety of rhamnose, 2-hydroxyethoxymethyl, and 1,3-dihydroxypropan-2-yloxy-methyl, respectively, exhibited quite strong anticancer activity. The underlying mechanism tests demonstrated that these compounds could induce apoptosis detected by DAPI staining, and Annexin V and propidium iodide binding. Cell cycle analysis indicated that the cancer cells were predominantly arrested at the G2/M phase when exposure to these compounds was examined by flow cytometry. These compounds may serve as lead candidates in the development of novel chemotherapeutics for cancer treatment.

Induction of apoptosis in human hepatoma SMMC-7721 cells by solamargine from Solanum nigrum L

ETHNOPHARMACOLOGICAL RELEVANCE

Solanum nigrum L. (SNL), a traditional Chinese medicinal herb endowed with diuretic, antipyretic and hepatoprotective effects, has been used as a major ingredient of folk prescriptions for anticancer treatment in China.

AIM OF THE STUDY

The purpose of this study was to evaluate the inhibitory effect of solamargine (SM), a major steroidal alkaloid glycoside purified from SNL, on human hepatoma SMMC-7721 cells and investigate the possible mechanism of SM.

MATERIALS AND METHODS

The MTT assay was used to evaluate the IC(50) on tumor cell lines. The effect on morphology was observed with a light or fluorescence microscopy. The rate of apoptosis and the cell cycle were measured using flow cytometry (FCM). The expression of caspase-3 protein was measured by colorimetric assay.

RESULTS

SM significantly inhibited the growth of SMMC-7721 and HepG2 cells and induced cell apoptosis. Cell cycle analysis revealed that SM caused cell cycle arrest at the G2/M phase. Moreover, SM could up-regulate the expression of caspase-3.

CONCLUSIONS

This study indicated that SM exerted potential anticancer activity on SMMC-7721 cells in vitro through the activation of caspase-3 and the regulation of the cell cycle progression to induce apoptosis and inhibit hepatoma cells proliferation.

Antimutagenic potential of Solanum lycocarpum against induction of chromosomal aberrations in V79 cells and micronuclei in mice by doxorubicin

Solanum lycocarpum A. St. Hil. (Solanaceae) is a hairy shrub or small much-branched tree of the Brazilian Cerrado. S. lycocarpum fruits are commonly used in traditional medicine in powder form or as folk preparations for the treatment of diabetes and obesity, as well as for controlling cholesterol levels. The aim of the present study was to chemically characterize the hydroalcoholic extract (SL) of S. lycocarpum by determination of total flavonoids and total poyphenols and quantification of steroidal alkaloids, as well as to evaluate its mutagenic and/or antimutagenic potential on V79 cells and Swiss mice using chromosomal aberrations and bone marrow micronucleus assays, respectively. Three concentrations of SL (16, 32, and 24 µg/mL) were used for the evaluation of its mutagenic potential in V79 cells and four doses (0.25, 0.50, 1.0, and 2.0 g/kg body weight) were used for Swiss mice. In the antimutagenicity assays, the different concentrations of SL were combined with the chemotherapeutic agent doxorubicin (DXR). HPLC analysis of SL gave contents of 6.57 % ± 0.41 of solasonine and 4.60 % ± 0.40 of solamargine. Total flavonoids and polyphenols contents in SL were 0.04 and 3.60 %, respectively. The results showed that not only SL exerted no mutagenic effect, but it also significantly reduced the frequency of chromosomal aberrations induced by DXR in both V79 cells and micronuclei in Swiss mice at the doses tested.

[Extraction, purification technology and antineoplastic effects of solamargine]

OBJECTIVE

To extract and purify of solamargine from Solanum nigrum, and to research its antineoplastic effects.

METHOD

S. nigrum was extracted refluently with 80% alcohol, solamargine was purified with silica gel column chromatography and recrystallization, and then conducted its structure identification and purity checks. Screened the effect on human tumor cell groth inhibition in vitro by MTT assay, and researched on the features in mice with H22 liver cancer or Ehrlich ascites tumor of solamargine.

RESULT

The concent of solamargine reached 97.9%. Solamargine had significantly inhibition on 6 tumor cells in vitro, and it had significantly inhibition on mice with H22 liver cancer or ehrlich ascites tumor in the 2.4 mg x kg(-1) dose of i.v.

CONCLUSION

Solamargine have the antineoplastic effect.

Induction of actin disruption and downregulation of P-glycoprotein expression by solamargine in multidrug-resistant K562/A02 cells

BACKGROUND

Solamargine (SM), a steroidal glycoalkaloid isolated from the Chinese herb Solanum incanum, has been shown to inhibit the growth of some cancer cell lines and induce significant apoptosis. However, the effects of SM on multidrug-resistant (MDR) cells and the molecular mechanisms involved are poorly understood. The purpose of this study was to evaluate the anti-MDR effects of SM and the associated mechanisms in MDR K562/A02 cells.

METHODS

The cytotoxicity of SM was measured by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. The 14',6-diamidino-2-phenylindole (DAPI) nuclear staining and flow cytometry were used to detect SM-induced apoptosis. The mRNA expression of P-glycoprotein (P-gp) was investigated by real-time PCR (RT-PCR). Western blotting was used to determine the expression of Bcl-2, Bax, and actin. The changes in the morphology of actin were examined with immunofluorescence staining.

RESULTS

MTT results showed that SM effectively killed the MDR sublines K562/A02, KB/VCR, and H460/paclitaxel (Taxol), and their parental cell lines K562, KB, and H460 to an equivalent or more sensitive degree. Based on the results by flow cytometry and immunostaining, the pro-apoptotic effects of SM were observed in MDR K562/A02 cells. Furthermore, the RT-PCR results showed that SM induced the downregulation of MDR1 mRNA. In addition, the expression of P-gp and actin was decreased in the SM-treated cells, as measured by western blotting and immunostaining.

CONCLUSIONS

These results demonstrate that SM effectively triggers apoptosis in MDR tumor cells, which is associated with actin disruption and downregulation of MDR1 expression. This compound may merit further investigation as a potential therapeutic agent that bypasses the MDR mechanism for the treatment of MDR tumors.

Total synthesis of solamargine

Solamargine, (25R)-3β-{O-α-L-rhamnopyranosyl-(1→2)-[O-α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyloxy}-22α-N-spirosol-5-ene, has been synthesized in 13 steps in a 10.5% overall yield starting from the naturally abundant diosgenin. Condensation of a partially protected glucopyranosyl donor with an oxaza-spiro moiety, which was formed in one-pot azido reduction, significantly improved the synthesis of desired molecule. The target compound exhibited good cytotoxic activities against tumor cells HeLa, A549, MCF-7, K562, HCT116, U87, and HepG2 with IC(50) ranging from 2.1 to 8.0 μM.

Anticonvulsant activity of solasodine isolated from Solanum sisymbriifolium fruits in rodents

CONTEXT

Solanum sisymbriifolium Lam. (Solanaceae), commonly known as sticky nightshade, is traditionally used for central nervous system (CNS) disorders. Although solasodine has been isolated from this plant, little is known about its anticonvulsant and CNS depressant actions.

OBJECTIVE

We investigated anticonvulsant and CNS depressant effects of solasodine isolated from S. sisymbriifolium using several experimental models.

MATERIALS AND METHODS

Swiss albino mice (n=6) were employed for pentylenetetrazole (PTZ) and picrotoxin (PCT)-induced convulsions and thiopental-induced sleep time. Different groups of Wistar albino rats (n=6) were subjected to maximal electroshock (MES) test. Solasodine, a steroidal glycoalkaloid, was isolated from dried fruits of S. sisymbriifolium and identified by GC-MS.

RESULTS

The results showed that intraperitoneal (i.p.) injection of solasodine (25 mg/kg) significantly delayed (p < 0.01) latency of hind limb tonic extensor (HLTE) phase in the PCT-induced convulsions. In the MES model, solasodine significantly reduced (p < 0.001) duration of HLTE at 25, 50, and 100 mg/kg, i.p. in a dose-dependent manner. Interestingly, solasodine did not produce any significant reduction in PTZ-induced convulsions. Prior treatment of solasodine (25, 50, and 100 mg/kg, i.p.) significantly potentiated thiopental-provoked sleep in a dose-dependent manner (p < 0.001).

DISCUSSION AND CONCLUSION

Our study, for the first time, shows potent anticonvulsant and CNS depressant activities of solasodine. It is likely that solasodine, in part, is responsible for the anticonvulsant and sedative properties of S. sisymbriifolium. The future study should focus on the exact mechanism of action of solasodine.

[Change of plasma endothelin-1 concentrations in photodynamic induced rat anterior ischemic optic neuropathy model and drug modulation]

OBJECTIVE

To investigate changes of plasma endothelin-1 (ET-1) concentration in photodynamic induced rat anterior ischemic optic neuropathy model (rAION) and evaluate the effects of compound anisodine hydrobromide (CA).

METHODS

Eighty-five Sprague-Dawley (SD) male rats were randomly divided into a blank control group of 10 rats and a model group of 75 rats. rAION model was established in the model group by photodynamic induction. The model group was divided into a rAION simple group of 25 rats, a CA intervention group of 25 rats, and a normal saline (NS) control group of 25 rats. Beginning from the day that the rAION model was established, temporal subcutaneous injections (once daily for 3 days) of CA and NS were performed in the CA and the NS groups, respectively. The plasma ET-1 concentrations were detected by radioimmunoassay and analyzed at 1, 3, 5, 7 and 14 days.

RESULTS

The means plasma ET-1 concentration of rAION simple group is (114.9±17.6) ng/L, higher than that of the control group (69.4±9.1) ng/L (t=14.92, P<0.01). In the rAION model group, the plasma ET-1 concentrations 1 to 5 days after the model was established were higher than that of 7 to 14 days. During observational periods, on the 1st, 5th, 7th and 14th day, there was no significant difference between the CA and NS groups (t=0.58, 2.07, 0.81 and 0.93, P>0.05), but on the 3rd day the level of plasma ET-1 concentration in the CA group was significantly lower than that of the NS group (t=4.72, P<0.05).

CONCLUSIONS

Increase of plasma ET-1 concentrations may play an important role in the pathogenesis of photodynamic induced rAION model. CA can decrease the plasma ET-1 concentrations in rAION rats.

Antinociceptive activity of steroid alkaloids isolated from Solanum trilobatum Linn

Solasodine (1) was isolated for the first time from the roots of Solanum trilobatum Linn., a member of the Solanaceae, and assessed for its presumed antinociceptive activity using several experimental murine models, viz. the writhing, formalin, and hot plate tests. When used at doses of 2, 4, and 8 mg/kg, this steroidal alkaloid caused a significant and dose-dependent decrease in the nociception induced by an intraperitoneal injection of acetic acid (p < 0.001). It also led to a significant reduction of the painful sensation caused by formalin in both phases of the formalin test (p < 0.001). Furthermore, the alkaloid produced a significant increase in the reaction time in the hot plate test (p < 0.001). These results suggest that solasodine elicited antinociceptive activity through both central and peripheral mechanisms.

[Effects of anisodamine on microcirculation of the asystole rats during the cardiopulmonary resuscitation]

OBJECTIVE

To study the effects of anisodamine (Ani) on microcirculation and reperfusion volume of intestine wall in Wistar rats during cardiopulmonary resuscitation (CPR) for cardiac arrest (CA).

METHODS

Healthy Wistar rats subjected to CA and resuscitation were randomly divided into four groups, 15 rats in each group. After a 4-minute-non-intervention interval, CPR was started. After CPR for 4 minutes the animals in control group received normal saline, group epinephrine (Epi) received Epi (bolus dose of 200 microg/kg), Epi plus low dosage Ani (Ld Ani) group received Epi plus Ani (bolus dose of 200 microg/kg Epi followed by Ani of 5 mg/kg), and Epi plus high dosage Ani (Hd Ani) group received Epi plus Ani (bolus dose of 200 microg/kg Epi followed by Ani of 10 mg/kg). The recanalization rate of mesenteric arterioles and venules, caliber of the recanalized mesentery arteriole and venule, and the reperfusion volume of intestine wall were observed in vivo in rats with restoration of spontaneous circulation (ROSC).

RESULTS

As the rate of recanalization of mesenteric arterioles and venules was compared, group Hd Ani (66.6%, 60.0%)>group Ld Ani (60.0%, 53.3%)>group control (40.0%, 40.0%)>group Epi (26.7%, 20.0%), and group Ld Ani and group Hd Ani was much better than group Epi(all P<0.05). When the caliber of arterioles and venules was compared, group Hd Ani>group Ld Ani>group control>group Epi 30 minutes and 60 minutes after ROSC. Thirty minutes after ROSC, the caliber of arterioles and venules was much larger in group Ld Ani and group Hd Ani than that in group Epi (all P<0.05). Sixty minutes after ROSC, there was no statistical difference in the caliber of venules between group Ld Ani and group Epi, so as between group Ld Ani and group Hd Ani. Reperfusion volume of intestine wall in group Ld Ani and group Hd Ani was higher than that in groups control and Epi 15 minutes after ROSC, and it kept on to be better up to 60 minutes after ROSC.

CONCLUSION

Administration of Ani at earlier period of resuscitation could improve microcirculation of the tissue and raise ROSC rate and successful rate of resuscitation.

Differential neuropsychopharmacological influences of naturally occurring tropane alkaloids anisodamine versus scopolamine

Two naturally occurring tropane alkaloids, anisodamine and scopolamine, structurally dissimilar in one OH group, are well established as muscarinic acetylcholine receptor (mAChR) antagonists in clinic and basic research. However, experimental evidence for central effects of anisodamine is limited and conflicting compared with that of scopolamine. In the present study, Morris water maze test, long-term potentiation (LTP) recording and receptor radioligand binding assays were used to explore the disparity in neuropsychopharmacological influences of anisodamine versus scopolamine and possible mechanisms. Anisodamine, at 10-40-fold higher doses than those of scopolamine, did not produce any spatial cognitive deficits as scopolamine, but tended to improve cognition at the repeated high doses. LTP in vivo was then adopted to predict BBB permeability of the muscarinic antagonists following systemic drug administration. Contrary to scopolamine, anisodamine did not influence the formation of LTP in the CA(1) region of rat hippocampus at 40-fold higher dose than that of scopolamine. Additionally, receptor radioligand binding assays (RRLBA) revealed that the binding affinity of anisodamine to mice brain mAChR was much lower than that of scopolamine. The findings suggested that anisodamine did not impair cognition nor depress LTP primarily due to its poor BBB permeability. This work enlarged knowledge of structure-activity relationship among tropane alkaloids, meanwhile providing evidence for more reasonable drug prescription in clinic.

Tropane alkaloids as medicinally useful natural products and their synthetic derivatives as new drugs

Secondary metabolites of Solanaceae plants, sharing tropane skeleton as a common structural feature, are sharply divided into two classes: tropine and ecgonine derivatives. The first group, represented by well known alkaloids: atropine and scopolamine, which are considered to be model anticholinergic drugs, continues to provide inspiration in the search for more selective muscarinic receptor antagonists. The second class accommodates one of the principal drugs of abuse, cocaine. Synthesis of much needed cocaine antagonists, despite extensive research, has not been particularly successful. Therefore, new concepts of cocaine abuse treatment resort to immunotherapy and biotechnology. Contemporary pharmaceutical industry manufactures over 20 active pharmaceutical substances containing tropane moiety in their structure, which are applied as mydriatics, antiemetics, antispasmodics, anesthetics and bronchodilators. There are two sources of raw materials for this industrial activity: natural products isolated from cultivated transgenic plants (mainly scopolamine and atropine from Australian Duboisia) and chemical synthesis based on common intermediate: tropinone, which can be further transformed by synthetic means to the following classes of compounds: tropine and its esters (tropeines), scopine and nortropine derivatives, and tropane quaternary ammonium salts. This survey focuses on new developments in chemistry and pharmacology of tropane derivatives, particularly in view of their prospective industrial applications as therapeutics.

[Inhibitory effects of anisodamine and pentoxifylline on the expression of lipopolysaccharide -induced intercellular adhesion molecule-1 in rat cardiac muscle]

OBJECTIVE

To investigate the inhibitory effects of anisodamine (654-2) and pentoxifylline (PTX) on the expression of lipopolysaccharide (LPS)-induced intercellular adhesion molecule-1 (ICAM-1) in rat cardiac muscle in vivo.

METHODS

The animals were randomly divided into five groups (each n=6): (1) normal control group, (2) model group, (3) 654-2 treated group, (4) PTX treated group and (5) 654-2+PTX treated group. The endotoxemia model was reproduced by intravenous injection LPS 5 mg/kg. The expression of ICAM-1 protein in rat cardiac muscle was assayed by Western blotting at 0, 2, 4, 6, 8, 10 hours after intravenous LPS injection. Then the expression of ICAM-1 protein in different groups was assayed at different time points.

RESULTS

The changes in expression of ICAM-1 in rat cardiac muscle after LPS injection were in a time-dependent pattern, gradually elevating to approach the peak at 6 th, then it lowered, but it still appeared at 10 hours (P<0.05). Western blotting also showed that ICAM-1 protein with decreased with pre-treatment of 654-2 or PTX respectively (both P<0.01). It was reduced to a much lower level when the animals were pretreated with a combination of 654-2 and PTX, compared with the group of 654-2 alone or PTX alone (both P<0.05).

CONCLUSION

The combination of 654-2 and PTX may play a protective role in rat against injury to cardiac muscle induced by LPS in vivo via inhibiting the production of ICAM-1 protein.

Downregulation of HER2/neu receptor by solamargine enhances anticancer drug-mediated cytotoxicity in breast cancer cells with high-expressing HER2/neu

Overexpression of HER2/neu is associated with drug resistance and poor outcome in breast cancer. Solamargine (SM), a glycoalkaloid purified from the herb Solanum incanum, exhibits HER2/neu gene modulation of HER2/neu high-expressing human breast cancer cell line ZR-75-1. SM downregulation of HER2/neu gene expression was determined by RT-PCR and Southern hybridization. Additionally, the membrane-bound HER2/neu receptor in highly HER2/neu-expressing breast cancer cells was determined by radioimmunoassay, immunocytochemistry, fluorescent immunocytochemistry, and flow cytometry. SM significantly decreased the number of HER2/neu receptors on the cell membrane. Methotrexate (MTX), 5-florouracil (5-Fu), and cisplatin (CDDP) are commonly used for breast carcinoma treatment in clinics; however, patients with HER2/neu overexpression exhibit resistance to these anticancer drugs. Notably, combination of MTX, 5-Fu, and CDDP with SM individually increased the susceptibility of breast cancer cells to these chemotherapeutic agents. Experimental results indicated that downregulation of HER2/neu by SM might be an effective strategy for enhancing drug susceptibility of breast cancer cells expressing high levels of HER2/neu.

Solamargine upregulation of Fas, downregulation of HER2, and enhancement of cytotoxicity using epirubicin in NSCLC cells

Nonsmall-cell lung cancer (NSCLC) is not generally a chemosensitive tumor, and the mechanism of resistance to the relevant anticancer drugs has not been fully elucidated. Solamargine (SM), the major steroidal glycoalkaloids extracted from the Chinese herb Solanum, inhibits the growth of human tumor cells. We have previously demonstrated that SM regulates tumor necrosis factor receptors (TNFRs)- and mitochondria-mediated pathways and sensitizes NSCLC cells to initiate apoptosis. Interestingly, this investigation reveals that SM up-regulated Fas expression and down-regulated the expression of HER2, whose overexpression is associated with resistance to drugs, and promotes chemotherapy-induced apoptosis in NSCLC A549 and H441 cells. After treatment with SM, the expression of HER2 mRNA was correlated with the expression of topoisomerase IIalpha (TOP2A) mRNA. The combinatory use of low concentrations of SM with low-toxic topoisomerase II inhibitor epirubicin accelerated apoptotic cell death. Therefore, the downregulation of the HER2 and TOP2A expression by SM with epirubicin may partially explain the SM and epirubicin cytotoxicity synergy effect in NSCLC. Results of this study suggest that SM induces Fas and TNFR-induced NSCLC cell apoptosis and reduces HER2 expression. These findings provide the synergistic therapeutic interaction between SM and epirubicin, suggesting that such combinations may be effectively exploited in future human cancer clinical trials.

Solamargine induces apoptosis and sensitizes breast cancer cells to cisplatin

Solamargine (SM), a major steroidal alkaloid glycoside, was purified from Solanum incanum plant. SM exhibited the most cytotoxic effect comparing with that of cisplatin (cDDP), methotrexate (MTX), 5-fluorouracil (5-FU), epirubicin (EPI) and cyclophosphamide (CP) against human breast cancer cells. In this study, SM induces apoptosis of the breast cancer cells and the mechanism was characterized. SM up-regulated the expressions of external death receptors, such as tumor necrosis factor receptor I (TNFR-I), Fas receptor (Fas), TNFR-I-associated death domain (TRADD), and Fas-associated death domain (FADD). SM also enhanced the intrinsic ratio of Bax to Bcl-2 by up-regulating Bax and down-regulating Bcl-2 and Bcl-xL expressions. These effects resulted in the release of mitochondrial cytochrome c and activation of caspase-8, -9 and -3 in the cells, indicating that SM triggered extrinsic and intrinsic apoptotic pathways of breast cancer cells. Similar to function way of SM, cDDP causes cancer cell apoptosis though caspase-8/caspase-3 and Bax/cytochrome c pathways, but the resistance to cDDP is correlated with Bcl-2 and Bcl-xL overexpression. However, the overexpression of Bcl-2 and Bcl-xL can be broken through by SM. The combined treatment of SM and cDDP significantly reduced Bcl-2 and Bcl-xL expressions, and enhanced Bax, cytochrome c, caspase-9 and -3 expressions in breast cancer cells. Thus, the combined use of SM and cDDP may be effective in cDDP-resistant breast cancer.

Efficacy and mechanisms of alpha-solasonine-and alpha-solamargine-induced cytolysis on two strains of Trypanosoma cruzi

Two genetically diverse strains of Trypanosoma cruzi were tested in vitro for susceptibility to the solanum-derived triglycoside alkaloids solasonine and solamargine. Cytolytic assays were performed on epimastigotes (EMs) and bloodstream form trypomastigotes (BSFs) lifecycle stages by using serial dilutions of each alkaloid. Each alkaloid effectively lysed both lifecycle stages, although solasonine routinely required higher concentrations to induce similar results. EMs demonstrated greater resistance to cytolysis than BSFs at equal concentrations of either alkaloid. No significant resistance could be correlated to parasite strain. The reported synergistic cytolytic effects observed upon compounding solasonine and solamargine together were also tested. We failed to identify any cytolytic synergism in cultures of EMs or BSFs. The role of rhamnose-binding proteins (RBPs) in mediating cytolysis was investigated through competitive inhibition experiments. The addition of exogenous L: -rhamnose to the media failed to reduce parasite attrition independent of the parasite lifecycle stage. Based on these results, we suggest the mechanisms involved in cytolysis of T. cruzi by solasonine and solamargine are largely independent of rhamnose receptor-specific interactions. We propose that attrition likely involves less-specific carbohydrate interactions, which lead to the formation and intercalation of sterol complexes into the parasite plasma membrane.

The pharmacological properties of anisodamine

Anisodamine is a naturally occurring atropine derivative that has been isolated, synthesized and characterized by scientists in the People's Republic of China. Like atropine and scopolamine, anisodamine is a non-specific cholinergic antagonist exhibiting the usual spectrum of pharmacological effects of this drug class. It appears to be less potent and less toxic than atropine and displays less CNS toxicity than scopolamine. Anisodamine has been shown to interact with and disrupt liposome structure which may reflect its effects on cellular membranes. Experimental evidence implicates anisodamine as an anti-oxidant that may protect against free radical-induced cellular damage. Its cardiovascular properties include depression of cardiac conduction and the ability to protect against arrhythmia induced by various agents. Anisodamine is a relatively weak alpha(1) adrenergic antagonist which may explain its vasodilating activity. Its anti-thrombotic activity may be a result of inhibition of thromboxane synthesis. The T(1/2) of anisodamine in humans is about 2-3 h. Numerous therapeutic uses of anisodamine have been proposed including treatment of septic shock, various circulatory disorders, organophosphorus (OP) poisoning, migraine, gastric ulcers, gastrointestinal colic, acute glomerular nephritis, eclampsia, respiratory diseases, rheumatoid arthritis, obstructive jaundice, opiate addiction, snake bite and radiation damage protection. The primary therapeutic use of anisodamine has been for the treatment of septic shock. Several mechanisms have been proposed to explain its beneficial effect though most mechanisms are based upon the assumption that anisodamine ultimately acts by an improvement of blood flow in the microcirculation. Preliminary studies suggest another important therapeutic use of anisodamine is for the treatment of OP poisoning. Additional research is needed to delineate further the clinical usefulness of anisodamine relative to other anti-muscarinic drugs such as atropine and scopolamine.

Efficient Synthesis of Solasodine,O-Acetylsolasodine, and Soladulcidine as Anticancer Steroidal Alkaloids

An efficient synthesis of the steroidal alkaloids solasodine (1), O-acetylsolasodine (2), and soladulcidine (3) starting from easily available diosgenin and tigogenin in five or six steps (overall yield 25, 24, and 28%, resp.) is described. Moreover, our synthetic route provides a selective modification at C(3) of 1 and related compounds in order to carry out lead optimization on these natural antitumor steroidal alkaloids.

Mechanism of inhibition of Ca2+-transport activity of sarcoplasmic reticulum Ca2+-ATPase by anisodamine

The mechanism of inhibition of Ca2+-transport activity of rabbit sarcoplasmic reticulum Ca 2+-ATPase (SERCA) by anisodamine (a drug isolated from a medicinal herb Hyoscyamuns niger L) was investigated by using ANS (1-anilino-8-naphthalenesulfonate) fluorescence probe, intrinsic fluorescence quenching and Ca 2+-transport activity assays. The number of ANS binding sites for apo Ca2+-ATPase was determined as 8, using a multiple-identical binding site model. Both anisodamine and Ca2+ at millimolar level enhanced the ANS binding fluorescence intensities. Only anisodamine increased the number of ANS molecules bound by SERCA from 8 to 14. The dissociation constants of ANS to the enzyme without any ligand, with 30 mM anisodamine and with 15 mM Ca 2 were found to be 53.0 microM, 85.0 microM and 50.1 microM, respectively. Both anisodamine and Ca2+ enhanced the ANS binding fluorescenc with apparent dissociation constants of 7.6 mM and 2.3 mM, respectively, at a constant concentration of the enzyme. Binding of anisodamine significantly decreased the binding capacity of Ca2+ with the dissociation constant of 9.5 mM, but binding of Ca2+ had no obvious effect on binding of anisodamine. Intrinsic fluorescence quenching and Ca2+-transport activity assays gave the dissociation constants of anisodamine to SERCA as 9.7 and 5.4 mM, respectively, which were consistent with those obtained from ANS-binding fluorescence changes during titration of SERCA with anisodamine and anisodamine + 15 mM Ca2+, respectively. The results suggest that anisodamine regulates Ca2+-transport activity of the enzyme, by stabilizing the trans-membrane domain in an expanded, inactive conformation, at least at its annular ring region.

Potato glycoalkaloids and metabolites: roles in the plant and in the diet

Potatoes, members of the Solanaceae plant family, serve as major, inexpensive low-fat food sources providing energy (starch), high-quality protein, fiber, and vitamins. Potatoes also produce biologically active secondary metabolites, which may have both adverse and beneficial effects in the diet. These include glycoalkaloids, calystegine alkaloids, protease inhibitors, lectins, phenolic compounds, and chlorophyll. Because glycoalkaloids are reported to be involved in host-plant resistance and to have a variety of adverse as well as beneficial effects in cells, animals, and humans, a need exists to develop a clearer understanding of their roles both in the plant and in the diet. To contribute to this effort, this integrated review presents data on the (a) history of glycoalkaloids; (b) glycoalkaloid content in different parts of the potato plant, in processed potato products, and in wild, transgenic, and organic potatoes; (c) biosynthesis, inheritance, plant molecular biology, and glycoalkaloid-plant phytopathogen relationships; (d) dietary significance with special focus on the chemistry, analysis, and nutritional quality of low-glycoalkaloid potato protein; (e) pharmacology and toxicology of the potato glycoalkaloids comprising alpha-chaconine and alpha-solanine and their hydrolysis products (metabolites); (f) anticarcinogenic and other beneficial effects; and (g) possible dietary consequences of concurrent consumption of glycoalkaloids and other biologically active compounds present in fresh and processed potatoes. An enhanced understanding of the multiple and overlapping aspects of glycoalkaloids in the plant and in the diet will benefit producers and consumers of potatoes.

Antitumor efficacy of the novel chemotherapeutic agent coramsine is potentiated by cotreatment with CpG-containing oligodeoxynucleotides

Coramsine is a novel chemotherapeutic agent isolated from Solanum linnaeanum (devil's apple). Topical treatment provides clinical benefit for skin tumors. To evaluate the potential broader applicability of the drug, its in vivo anticancer efficacy in a murine model of malignant mesothelioma and its mode of action were investigated. Systemic administration of coramsine slowed tumor growth and prolonged survival time. Importantly, the antitumor efficacy of coramsine was enhanced when treatment was combined with stimulation of innate immunity using unmethylated CpG-containing oligodeoxynucleotides (ODNs). Combination treatment further slowed tumor growth and provided a survival benefit. Coramsine seems to kill tumor cells by direct cell lysis. Using 2 different assays to detect apoptosis (caspase activation and DNA fragmentation), we found no evidence that coramsine induces any form of programmed cell death. The fact that the efficacy of coramsine is potentiated by CpG ODNs suggests that coramsine-induced cell death is an immunologic null event.

Specific inhibitory action of anisodamine against a staphylococcal superantigenic toxin, toxic shock syndrome toxin 1 (TSST-1), leading to down-regulation of cytokine production and blocking of TSST-1 toxicity in mice

Toxic shock syndrome toxin 1 (TSST-1), produced by Staphylococcus aureus (including methicillin-resistant S. aureus), is a superantigenic toxin responsible for toxic shock syndrome as well as neonatal TSS-like exanthematous disease. TSST-1 exhibits its deleterious effects by leading to the abnormal proliferation of, e.g., Vbeta2+ T cells and overproduction of proinflammatory cytokines. In the present study we examined the inhibitory effect of a Chinese herbal extract, anisodamine, on TSST-1 using human peripheral blood mononuclear cells (PBMCs). Anisodamine inhibited the production of proinflammatory cytokines better than interleukin-10 (an anti-inflammatory cytokine). The inhibitory effect of anisodamine was greater than that of any tropane alkaloid examined. Anisodamine acted directly on both monocytes and T cells in human PBMCs, and the effect was confirmed at the transcriptional level. Inhibition of NF-kappaB activation was also demonstrated. In contrast, no significant inhibition of Vbeta2+ T-cell proliferation was observed. In mice injected with TSST-1, anisodamine treatment significantly decreased serum proinflammatory cytokine levels and prevented TSST-1-induced death. These results suggest that anisodamine specifically acts against the production of cytokines (inflammatory cytokines in particular) and not against Vbeta2+ T-cell proliferation and that anisodamine may have a beneficial effect on TSST-1-associated disease.