Perovskone, a Potential Antiplasmodial Lead Compound from Salvia hydrangea; Derivatization and Quantification

Perovskone (1) was isolated as an antiplasmodial lead from Salvia hydrangea, semisynthetic derivatization of (1) let to find more potent antiplasmodial compound (2)(IC50=0.08 μM, SI=83.8).The perovskone content in leaves and flowers was 0.053% and 0.04% of dried weight of plant material, respectively.   Introduction: Malaria, caused by five different Plasmodium species, is the most virulent tropical parasitic disease. According to latest WHO estimates, 212 million cases of malaria and 429 deaths have been reported in 2015. Artemisinin-resistant P. falciparum strains have been detected in some countries recently, which is really problematic and illustrates the urgent need for new drugs or lead structures.  Natural products have served as a major source of drugs for centuries, and about half of the pharmaceuticals in use today are derived from natural products. As a part of an ongoing screening for new antiplasmodial natural products, an n-hexane extract of S. hydrangea showed promising activity with the IC50value of 3.2 μg/mL. S. hydrangea distributed widely in Iran. Preparations from flowers serve as an anthelmintic and antileishmanial in the Pars province.  Large scale isolation of the n-hexane extract led to (1). Herein we report on the isolation, derivatization and quantification of (1) together with in vitro antiplasmodial activity. Methods and Results:Fractionation of the n-hexane extract by open column chromatography on silica gel afforded (1) as a major constituent. It has shown potent in vitro antiplasmodial activity with IC50 value of 0.19 μM and selectivity index (SI) of 169.5. The semisynthetic derivatization of (1) resulted compound(2). As for (2) antiplasmodial activity was improved in comparison with (1). The perovskone content of different parts of plant (leaves and flowers) was analyzed by HPLC using UV detection. Its level in leaves and flowers was 0.053% and 0.04% of dried weight of plant material, respectively. Conclusions:Perovskone, a major constituent from S. hydrangea, can be considered as a potential antiplasmodial lead compound. In order to find more potent antiplasmodial semisynthetic derivatives and mechanism of action as well as in vivo examinations, further studies are suggested

7-epi-Clusianone, a Multi-Targeting Natural Product with Potential Chemotherapeutic, Immune-Modulating, and Anti-Angiogenic Properties

Targeted therapies have changed the treatment of cancer, giving new hope to many patients in recent years. The shortcomings of targeted therapies including acquired resistance, limited susceptible patients, high cost, and high toxicities, have led to the necessity of combining these therapies with other targeted or chemotherapeutic treatments. Natural products are uniquely capable of synergizing with targeted and non-targeted anticancer regimens due to their ability to affect multiple cellular pathways simultaneously. Compounds which provide an additive effect to the often combined immune therapies and cytotoxic chemotherapies, are exceedingly rare. These compounds would however provide a strengthening bridge between the two treatment modalities, increasing their effectiveness and improving patient prognoses. In this study, 7-epi-clusianone was investigated for its anticancer properties. While previous studies have suggested clusianone and its conformational isomers, including 7-epi-clusianone, are chemotherapeutic, few cancer types have been demonstrated to exhibit sensitivity to these compounds and little is known about the mechanism. In this study, 7-epi-clusianone was shown to inhibit the growth of 60 cancer cell types and induce significant cell death in 25 cancer cell lines, while simultaneously modulating the immune system, inhibiting angiogenesis, and inhibiting cancer cell invasion, making it a promising lead compound for cancer drug discovery

DataSheet1_Expression, purification and folding of native like mitochondrial carrier proteins in lipid membranes.docx

Mitochondrial Carrier Family proteins (MCFs) are located in the mitochondrial inner membrane and play essential roles in various cellular processes. Due to the relatively low abundance of many members of the family, in vitro structure and function determination of most MCFs require over-expression and purification of recombinant versions of these proteins. In this study, we report on a new method for overexpression of MCFs in Escherichia coli (E. coli) membranes, efficient purification of native-like proteins, and their reconstitution in mitochondrial inner membrane lipid mimics. cDNAs of Uncoupling Protein 4 (UCP4), Adenine Nucleotide Translocase (ANT) and Phosphate Translocase (PiT) were subcloned into the pET26b (+) expression vector such that fusion proteins with a short N-terminal pelB leader sequence and a six-histidine tag were produced to target the proteins toward the inner membrane of E. coli and facilitate affinity purification, respectively. Utilizing a modified autoinduction method, these proteins were overexpressed and extracted from the membrane of E. coli BL21 (DE3) and two modified strains, E. coli BL21 C43 (DE3) and E. coli BL21 Lobstr (DE3), in high yields. The proteins were then purified by immobilized metal affinity chromatography as monomers. Purity, identity, and concentration of the eluted monomers were determined by semi-native SDS-PAGE, Western blotting and mass spectrometry, and a modified Lowry assay, respectively. Cleavage of the pelB leader sequence from proteins was verified by mass spectrometric analysis. The purified proteins, surrounded by a shell of bacterial membrane lipids, were then reconstituted from the mild non-denaturing octyl glucoside (OG) detergent into phospholipid liposomes. Monomeric UCP4 spontaneously self-associated to form stable tetramers in lipid membranes, which is consistent with our previous studies. However, PiT and ANT remained dominantly monomeric in both detergent and liposome milieus, as detected by a combination of spectroscopic and electrophoretic methods. Native-like helical conformations of proteins were then confirmed by circular dichroism spectroscopy. Overall, this study demonstrates that targeting mitochondrial carrier family proteins to E. coli membranes provides an effective expression system for producing this family of proteins for biophysical studies.</p

Chemical constituents from the ethyl acetate extract of Salvia hydrangea DC. ex Benth

One new triterpenoid, 3β-O-(2-hydroxybenzoyl)-ursolic acid (1), and 11 known compounds, including 5 triterpenoids, 2 steroidal compounds, and 4 phenolic compounds were isolated from the ethyl acetate extract of the aerial parts of Salvia hydrangea. Their structures were elucidated based on the extensive spectroscopic data, including 1-dimensional and 2-dimensional nuclear magnetic resonance spectra, high resolution-electrospray ionization mass spectrometry, and by comparison with literature data. The antiprotozoal activity of compound 1 was evaluated against Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani, Plasmodium falciparum and showed no activities against all parasite tested

Terpenoids and phenolics of Micromeria persica

Phytochemical investigation of the aerial parts of Micromeria persica led to the isolation of a new oleane type triterpenoid ester (1), together with six known compounds 2–7), comprising one phenyl ethanoid ester, one glycosylated flavonoid, two triterpenoids, and two steroids. Their structures were elucidated by interpretation of their one-dimensional and two-dimensional NMR spectra and completed by the analysis of the HRESIMS data. Compounds 1 and 3 were evaluated for their cytotoxic feature against human breast adenocarcinoma cell line (MDA-MB231) and human prostate cancer cell line (DU145). However, they did not show positive effect (IC50 > 75µM)

A multi-targeting natural compound with growth inhibitory and anti-angiogenic properties re-sensitizes chemotherapy resistant cancer.

Targeted therapies have become the focus of much of the cancer therapy research conducted in the United States. While these therapies have made vast improvements in the treatment of cancer, their results have been somewhat disappointing due to acquired resistances, high cost, and limited populations of susceptible patients. As a result, targeted therapeutics are often combined with other targeted therapeutics or chemotherapies. Compounds which target more than one cancer related pathway are rare, but have the potential to synergize multiple components of therapeutic cocktails. Natural products, as opposed to targeted therapies, typically interact with multiple cellular targets simultaneously, making them a potential source of synergistic cancer treatments. In this study, a rare natural product, deacetylnemorone, was shown to inhibit cell growth in a broad spectrum of cancer cell lines, selectively induce cell death in melanoma cells, and inhibit angiogenesis and invasion. Combined, these results demonstrate that deacetylnemorone affects multiple cancer-related targets associated with tumor growth, drug resistance, and metastasis. Thus, the multi-targeting natural product, deacetylnemorone, has the potential to enhance the efficacy of current cancer treatments as well as reduce commonly acquired treatment resistance

Antiprotozoal germacranolide sesquiterpene lactones from Tanacetum sonbolii

A phytochemical investigation of extracts from flowers and aerial parts of; Tanacetum sonbolii; afforded 7 new germacranolide sesquiterpene lactones. The structures were established by a combination of 1- and 2-dimensional nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and electronic circular dichroism. The; in vitro; antiprotozoal activity of the compounds against; Trypanosoma brucei rhodesiense; and cytotoxicity against rat myoblast (L6) cells were determined. Compounds 4: and 5: showed IC; 50; values of 5.1 and 10.2 µM and selectivity indices of 3.9 and 4.0, respectively

Antiprotozoal diterpenes from Perovskia abrotanoides

As part of a screening for new antiparasitic natural products from Iranian plants, n-hexane and ethyl acetate extracts from the aerial parts of Perovskia abrotanoides were found to exhibit strong inhibitory activity against Trypanosoma brucei rhodesiense and Leishmania donovani. The activity was tracked by high-performance liquid chromatography (HPLC)-based activity profiling. Preparative isolation by a combination of silica gel column chromatography and HPLC afforded 17 diterpenoids (1: -17: ), including 14 abietane-, two icetexane-, and one isopimarane-type derivatives. Among these, (5R,10S)-11-hydroxy-12-methoxy-20-norabieta-8,11,13-triene (2: ), 12-hydroxy-norabieta-1(10),8,11,13-tetraene-1,11-furan (6: ), and 12-methoxybarbatusol (9: ) were new compounds, the structure of which was established by comprehensive spectroscopic data analysis (one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism). The antiprotozoal activity of the isolated compounds was evaluated against T. b. rhodesiense, Trypanosoma cruzi, L. donovani, and Plasmodium falciparum. Selectivity indexes (SI) were calculated in comparison to cytotoxicity on rat myoblast (L6) cells. Particularly active were 7α-ethoxyrosmanol (4: ) with an IC50 of 0.8 µM against T. b. rhodesiense (SI 14.9) and an IC50 of 1.8 µM (SI 6.9) against L. donovani, ferruginol (8: ) with an IC50 of 2.9 µM (SI 19.2) against P. falciparum, and miltiodiol (10: ) with an IC50 of 0.5 µM (SI 10.5) against T. b. rhodesiense. None of the compounds exhibited selective toxicity against T. cruzi (SI ≤ 1.6)