Hepatoprotective Activity of Betulin and Dipterocarpol Derivatives

Russian Journal of Bioorganic Chemistry - The regioselective synthesis of betulin 3,28-bis- and 28-monoacylates (nicotinate and isonicotinates) as well as of 3β-hemisuccinyl dipterocarpol was...     

Synthesis and Pharmacological Activity of Betulin Dinicotinate

The assignment of NMR resonances of lupane triterpenoids was refined by the example of 3O,28O-dinicotinoylbetulin, obtained by acylation of betulin. Hepatoprotective, antiulcer, antiinflammatory, reparative, and anti-HIV activities were found for the compound. In addition, it was demonstrated to have immunomodulatory activity, for the first time detected among lupane triterpenoids.     

Antiviral Activity of Acyl Derivatives of Betulin and Betulinic and Dihydroquinopimaric Acids

Russian Journal of Bioorganic Chemistry - The paper reports on the synthesis of a series of acyl derivatives of betulin and dihydroquinopimaric acid and the study of their antiviral activity...     

The Effect of Lactobacillus casei 32G on the Mouse Cecum Microbiota and Innate Immune Response Is Dose and Time Dependent

Lactobacilli have been associated with a variety of immunomodulatory effects and some of these effects have been related to changes in gastrointestinal microbiota. However, the relationship between probiotic dose, time since probiotic consumption, changes in the microbiota, and immune system requires further investigation. The objective of this study was to determine if the effect of Lactobacillus casei 32G on the murine gastrointestinal microbiota and immune function are dose and time dependent. Mice were fed L. casei 32G at doses of 10⁶, 10⁷, or 10⁸ CFU/day/mouse for seven days and were sacrificed 0.5h, 3.5h, 12h, or 24h after the last administration. The ileum tissue and the cecal content were collected for immune profiling by qPCR and microbiota analysis, respectively. The time required for L. casei 32G to reach the cecum was monitored by qPCR and the 32G bolus reaches the cecum 3.5h after the last administration. L. casei 32G altered the cecal microbiota with the predominance of Lachnospiraceae IS, and Oscillospira decreasing significantly (p < 0.05) in the mice receiving 10⁸ CFU/mouse 32G relative to the control mice, while a significant (p < 0.05) increase was observed in the prevalence of lactobacilli. The lactobacilli that increased were determined to be a commensal lactobacilli. Interestingly, no significant difference in the overall microbiota composition, regardless of 32G doses, was observed at the 12h time point. A likely explanation for this observation is the level of feed derived-nutrients resulting from the 12h light/dark cycle. 32G results in consistent increases in Clec2h expression and reductions in TLR-2, alpha-defensins, and lysozyme. Changes in expression of these components of the innate immune system are one possible explanation for the observed changes in the cecal microbiota. Additionally, 32G administration was observed to alter the expression of cytokines (IL-10rb and TNF-α) in a manner consistent with an anti-inflammatory response.     

Synthesis and Cytotoxic Activity of Thiazolofluorenone Derivatives

The synthesis and biological evaluation of some novel thiazolofluorenones, thiazolofluorenes and thiazoloanthraquinones, substituted with amino side-chains are described. These polyheterocyclic compounds have been synthesized via the corresponding imino-1,2,3-dithiazoles. Their cytotoxic activity and their eventual selective effect on a phase of the cell cycle were evaluated in vitro, using the murine lymphocytic L1210 leukaemia cell line.     

Cell Migration Velocities In the Crypts of the Small Intestine After Cytotoxic Insult Are Not Dependent On Mitotic Activity

Abstract. The role of mitotic activity in the normal process of intestinal epithelial cell migration was investigated. the movement of [³H]TdR-labelled cells in the crypt-villus column was used to study migration both in the crypts and on the villi. Radiation alone or in conjunction with other cytotoxic agents (hydroxyurea, cyclophosphamide and isopropyl-methane sulphonate) was used to eliminate cell division activity and to decrease crypt cellularity. This was done in order to determine the role of 'mitotic pressure' in driving cell migration.
It has been clearly demonstrated in this study that cell migration, both within the crypts and on the villi, can take place in the complete absence of mitotic activity and after a drastic decrease in crypt cellularity. These results add to the continually mounting evidence against the idea that the 'pressure' generated by mitoses within the crypt or indeed in other epithelial regions is responsible for propelling epithelial cells. the data also demonstrate that the migration mechanisms are resistant to cytotoxic exposure.     

剑麻提取物的细胞毒活性研究

用溶剂萃取法对剑麻的95%乙醇提取物进行分段处理,利用MTT法测定各提取部位的体外细胞毒活性。正丁醇提取物对肿瘤细胞株K-562、SMMC-7721和SGC-7901显示有生长抑制活性,IC50值分别为5.6、23.8和26.8μg/mL,而石油醚、乙酸乙酯和水溶性部位则没有活性。     

The Oncolytic Activity of Newcastle Disease Virus NDV-HUJ on Chemoresistant Primary Melanoma Cells Is Dependent on the Proapoptotic Activity of the Inhibitor of Apoptosis Protein Livin

Patients with advanced melanoma usually do not benefit from conventional chemotherapy treatment. There is therefore a true need for a new kind of therapy for melanoma. One factor responsible for the poor prognosis of melanoma is the inhibitor of apoptosis protein (IAP) family member Livin. In this study, we applied a novel approach for the treatment of melanoma, using a unique strain of the oncolytic Newcastle disease virus (NDV-HUJ). We found that, unlike chemotherapeutic drugs, NDV-HUJ, a one-cycle replicating virus, overcomes the resistance to apoptosis of melanoma primary cultures that over express the Livin protein. In contrast, melanoma tumor cells that do not express Livin are relatively resistant to NDV-HUJ treatment. Furthermore, we show that NDV-HUJ-induced oncolysis is attributed to the dual function of Livin: although Livin inhibits apoptosis through the inhibition of caspases, under the robust apoptotic stimulation of NDV-HUJ, caspases can cleave Livin to create a truncated protein with a paradoxical proapoptotic activity. Thus, NDV-HUJ is a potent inducer of apoptosis that can overcome the antiapoptotic effect of Livin and allow cleavage of Livin into the proapoptotic tLivin protein. Moreover, the results indicate that the interferon system, which is functional in melanoma, is not involved in NDV-induced oncolysis. Taken together, our data offer the possibility of a new viral oncolytic treatment for chemoresistant melanoma.Newcastle disease virus (NDV) is an avian paramyxovirus that has a potential selective oncolytic effect on human tumors (5, 7, 13, 21, 25, 26). NDV''s natural host is avian, and while mammalian cells bear the sialic acid receptor for NDV and may be infected by the virus, the virus has limited replication capacity in normal mammalian cells (21). We recently reported the development of an attenuated (lentogenic) isolate of NDV (HUJ) that undergoes only one cycle replication in infected mammalian cells (7, 25). NDV-HUJ is a single clone derived from the parental strain NDV Hitchner B1, which contains a mixed viral population. The new virus clone is attenuated due to multiple passages in specific-pathogen-free (SPF) eggs, and its intracerebral pathogenicity index (ICPI) value is low (an ICPI of 0.01 versus an ICPI of 0.93 for the parental NDV Hitchner B1). Sequence analysis of NDV-HUJ indicated 156 changes at the nucleotide sequence level and multiple amino acid changes from the parental B1 virus in all six viral genes (see Fig. S1 in the supplemental material). Although NDV-HUJ is an attenuated virus in chicken, it retains a selective cytotoxic potential for cancer cells, as determined in vitro and in vivo, using murine and human lung carcinomas (25). The oncolytic effect of the virus is apoptosis dependent (25). NDV-HUJ has been applied to treat glioblastoma patients in a phase I/II clinical trials and found to be safe and potentially active (7).The inhibitors of apoptosis proteins (IAPs) are receiving increased attention as key players in the initiation of tumors, their progression, and resistance to chemotherapy treatment (17). To date, eight human IAPs have been identified, including Livin. IAPs are characterized by one or more repeats of a highly conserved 70-amino-acid domain termed the baculovirus IAP repeat (BIR) that can bind and inhibit caspases, some IAPs also contain a conserved sequence termed the RING finger. RING finger proteins might function as E3 ubiquitin ligases; however, the exact nature of the E3 ligase activity of IAPs is still largely unclear.IAPs inhibit apoptosis induced by a variety of stimuli, mainly through their ability to bind and inhibit specific caspases (17). Intense study has shown that the role of IAP in apoptosis regulation is highly diverse, with a prominent role in tumorigenesis and resistance to therapy. Among the human IAPs, XIAP is the best characterized and the most potent caspase inhibitor. The most recently discovered member of this family is Livin, found by us and others (3, 9, 12, 24). Livin contains a single BIR domain and a RING finger (3, 12). We previously found that Livin is specifically cleaved by caspases at the Asp52 residue to produce a large C-terminal fragment, containing both the BIR and the RING domains. After cleavage, truncated Livin (tLivin) acts paradoxically as a proapoptotic factor (18, 19).In the present study we show that chemoresistant melanoma primary cultures that highly express the Livin protein are sensitive to oncolytic NDV-HUJ treatment. This appears to be a result of activation of caspases 8, 3, and 7 that in turn cleave Livin to produce the tLivin. This is a novel regulatory mechanism in which NDV-HUJ can overcome the antiapoptosis function of Livin and expose the “good side” of Livin by inducing the cleavage of Livin to produce the proapoptotic tLivin that subsequently leads to metastatic melanoma cell death.     

Cytotoxic Activity of Cunila angustifolia Essential Oil

The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and analyzed by GC‐FID and GC‐MS to determine its chemical composition. The essential oil presented pulegone (29.5 %) and isomenthol (27.0 %) as major components, and other compounds such as menthone (8.6 %), neomenthol (7.2 %), menthyl acetate (2.5 %) and caryophyllene oxide (2.0 %) were identified. The cytotoxic activity of the essential oil was evaluated by MTS assay, with the human cancer cell lines of the lung (A549), breast (MCF‐7) and skin melanoma (SK‐Mel‐28). The assay showed the highest selectivity, to MCF‐7 cell lines, with IC₅₀ equal to 34.0 μg mL^?1, low selectivity for SK‐Mel‐28 cell lines, with IC₅₀ equal to 279.9 μg mL^?1, and no mortality to A549 cell lines.     

Cytotoxic and Antimicrobial Activity of Dehydrozingerone based Cyclopropyl Derivatives

A small series of 1‐acetyl‐2‐(4‐alkoxy‐3‐methoxyphenyl)cyclopropanes was prepared, starting from dehydrozingerone (4‐(4‐hydroxy‐3‐methoxyphenyl)‐3‐buten‐2‐one) and its O‐alkyl derivatives. Their microbiological activities toward some strains of bacteria and fungi were tested, as well as their in vitro cytotoxic activity against some cancer cell lines (HeLa, LS174 and A549). All synthesized compounds showed significant antimicrobial activity and expressed cytotoxic activity against tested carcinoma cell lines, but they showed no significant influence on normal cell line (MRC5). Butyl derivative is the most active on HeLa cells (IC₅₀ = 8.63 μm ), while benzyl one is active against LS174 and A549 cell lines (IC₅₀ = 10.17 and 12.15 μm , respectively).     

口服抗乙肝转移因子免疫活性研究

采用肌肉和皮内混合免疫方法 ,将乙肝疫苗给猪接种。全程免疫 5次 ,2个月后 ,取脾脏和淋巴结制成口服抗乙肝转移因子。在小鼠体内进行了白细胞粘附抑制试验 ,结果表明口服抗乙肝转移因子具有依赖抗原的特异性免疫活性。     

Genetic Basis of Haloperidol Resistance in Saccharomyces cerevisiae Is Complex and Dose Dependent

The genetic basis of most heritable traits is complex. Inhibitory compounds and their effects in model organisms have been used in many studies to gain insights into the genetic architecture underlying quantitative traits. However, the differential effect of compound concentration has not been studied in detail. In this study, we used a large segregant panel from a cross between two genetically divergent yeast strains, BY4724 (a laboratory strain) and RM11_1a (a vineyard strain), to study the genetic basis of variation in response to different doses of a drug. Linkage analysis revealed that the genetic architecture of resistance to the small-molecule therapeutic drug haloperidol is highly dose-dependent. Some of the loci identified had effects only at low doses of haloperidol, while other loci had effects primarily at higher concentrations of the drug. We show that a major QTL affecting resistance across all concentrations of haloperidol is caused by polymorphisms in SWH1, a homologue of human oxysterol binding protein. We identify a complex set of interactions among the alleles of the genes SWH1, MKT1, and IRA2 that are most pronounced at a haloperidol dose of 200 µM and are only observed when the remainder of the genome is of the RM background. Our results provide further insight into the genetic basis of drug resistance.     

The Mucosal Adjuvant Cyclic di-AMP Exerts Immune Stimulatory Effects on Dendritic Cells and Macrophages

The cyclic di-nucleotide bis-(3′,5′)-cyclic dimeric adenosine monophosphate (c-di-AMP) is a candidate mucosal adjuvant with proven efficacy in preclinical models. It was shown to promote specific humoral and cellular immune responses following mucosal administration. To date, there is only fragmentary knowledge on the cellular and molecular mode of action of c-di-AMP. Here, we report on the identification of dendritic cells and macrophages as target cells of c-di-AMP. We show that c-di-AMP induces the cell surface up-regulation of T cell co-stimulatory molecules as well as the production of interferon-β. Those responses were characterized by in vitro experiments with murine and human immune cells and in vivo studies in mice. Analyses of dendritic cell subsets revealed conventional dendritic cells as principal responders to stimulation by c-di-AMP. We discuss the impact of the reported antigen presenting cell activation on the previously observed adjuvant effects of c-di-AMP in mouse immunization studies.     

Cytotoxic Activity of Dammarane Triterpenoids from Birch Leaves

Cytotoxic activity of dammarane triterpenoids isolated from birch leaves was studied. These substances differ from the native ginseng genin (20(S)-protopanaxadiol) by the number, location, or configuration of OH-groups. Using fertilized egg cells of sea urchin Strongylocentrotus intermedius we demonstrate that the orientation of C-3 OH-group has no effect on cytotoxic activity of triterpenoids as well as a higher activity of a triterpenoid with 3,12-OH as compared to a C-3 ketone but lower activity as compared to a triterpenoid with 3,17-OH. Depending on the number of OH-groups the cytotoxic activity of triterpenoids decreases in the row: tetraol > pentaol > triol. Dammar-24-ene-3,12,17,20(S)-tetraol (compound IV) is cytotoxic for the Ehrlich ascite carcinoma cells and this effect is additive to cytotoxic activity of anthracycline antibiotic carminomycin in vitro. Compound IV changes the permeability and microviscosity of the tumor cell membranes.     

Cytotoxic and Anti-Inflammatory Activity of 3,19-Isopropylidene-/Arylidene-Andrographolide Analogs

A series of 3,19-isopropylidene-/or arylidene-andrographolide analogs were synthesized and their structures were confirmed by NMR spectroscopic methodology. Twenty-five analogs were evaluated for their in vitro cytotoxic activity against HT-29, HepG2 and LNCaP cancer cell lines based on the sulforhodamine B (SRB) assay. Analog 2 f exhibited the most potent cytotoxic activity, with IC₅₀ values of 11.14 and 9.25 μM on HepG2 and LNCaP cancer cell lines, respectively. Esterification of hydroxy functional group at position C-14 in andrographolide analogs, 2 a and 2 b _, showed somewhat higher cytotoxicity than the precursor. In addition, andrographolide analogs ( 2 a – 2 d , 2 f , 3 a , 4 a and 4 h ) were evaluated for the NO inhibitory activity in the LPS stimulated RAW264.7 macrophages. The most active analog 2 a significantly reduced nitric oxide (NO) production from LPS stimulated RAW264.7 cells, with IC₅₀ values of 0.34±0.02 μM providing encouraging results for anti-inflammatory compound development.     

Enhanced Activity of Deoxycytidine Kinase After Pulsed Low Dose Rate and Single Dose Gamma Irradiation

In both pulsed low dose rate (LDR) and single high dose radiation schedules, gemcitabine pretreatment sensitizes tumor cells to radiation. These radiosensitizing effects could be the result of decreased DNA repair. In this study, the effect of irradiation on the deoxycytidine kinase (dCK) needed for DNA repair was investigated. The activity of dCK, a deoxynucleoside analogue-activating enzyme was increased upon irradiation in both schedules. No change in dCK protein expression was observed that indicates a post-translational regulation. The benefit of this increased activity induced by irradiation should be further investigated in combination with deoxynucleoside analogues activated by this enzyme.