Chemoprevention of Leishmaniasis: In-vitro antiparasitic activity of dibenzalacetone,a synthetic curcumin analog leads to apoptotic cell death in Leishmania donovani

Curcumin is the major phenolic compound found in turmeric, a dry powder of rhizomes and roots of the plant, Curcuma longa L., which is widely used as spice and food colorant around the world, and in herbal medicinal practice in Asian countries. The present study reports the leishmanicidal activity of trans-dibenzalacetone (DBA), a synthetic monoketone analog of curcumin, against Leishmania donovani parasites. We for the first time report the antiproliferative effect of a curcumin analog (DBA) on the intracellular amastigotes of L. donovani, the clinically more relevant stage of the parasite than its promastigotes stage. The leishmanicidal effect of DBA was further confirmed by scanning and transmission electron microscopies. Cell growth was arrested in G0/G1 phase with increased concentration of cytosolic calcium and dissipation of mitochondrial membrane potential. Further, the unique trypanothione/trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by DBA. This economically synthesizable simple monoketone analog of curcumin has the potential for field use against visceral leishmaniasis which is currently widespread in tropical and subtropical developing countries of the world. In conclusion, we have identified an analog of curcumin for potential applications against leishmaniasis, based on its strong antiparasitic activity and low toxicity. This curcumin analog compares favorably, at least in vitro, with the existing medication miltefosine.     

Syntheses and antifilarial profile of 7-chloro-4-(substituted amino) quinolines: a new class of antifilarial agents

The syntheses of 7-chloro-4-(substituted amino) quinolines (2-22) and their antifilarial activities are delineated. Some of the screened compounds have shown promising filarial response and sterilization effect on female Acanthocheilonema viteae in rodents.     

Induction of cytochrome P-450IA1 in fetal rat liver by a single dose of 3-methylcholanthrene.

Pregnant Sprague-Dawley rats were treated with a single ip dose of either olive oil or 40 mg/kg of 3-methylcholanthrene on gestation day 20 and sacrificed at various times after injection. Determination of aryl hydrocarbon hydroxylase activity 24 hr after injection revealed that treatment with 3-methylcholanthrene resulted in a 10.5-fold stimulation of enzymatic activity in liver 800 x g supernatants. Western blot analysis with monoclonal antibody 1-7-1 confirmed these results and demonstrated the presence of a 3-methylcholanthrene-inducible P-450 isozyme. Using Northern and slot blot techniques, the induction of steady-state levels of CYPIA1 RNA was shown to occur as early as 4 hr following 3-methylcholanthrene injection. CYPIA1 RNA levels were induced 31.6-fold over values obtained from oil-treated tissues at this time. This appears to be the optimal time to study changes in the levels of CYPIA1 RNA gene expression in the fetus following transplacental exposure to polycyclic aromatic hydrocarbons. By 12 to 24 hr postinjection, the induction of CYPIA1 RNA levels declined to 3.5- to 8.5-fold above control values. These results demonstrate that the kinetics of induction of the CYPIA1 gene during the fetal period differed from that seen in adults.     

Factors Affecting Inducible Expression of Outer Membrane Protein A (OmpA) of <Emphasis Type="Italic">Shigella dysenteriae</Emphasis> Type-1 in <Emphasis Type="Italic">Lactococcus lactis</Emphasis> Using Nisin Inducible Controlled Expression (NICE)

Potential use of Lactococcus lactis (L. lactis) as a heterologous protein expression host as well as for delivery of multiple therapeutic proteins has been investigated extensively using Nisin Inducible Controlled Expression (NICE) system. Optimum inducible expression of heterologous protein by NICE system in L. lactis depends on multiple factors. To study the unexplored role of factors affecting heterologous protein expression in L. lactis using NICE, the present study outlines the optimization of various key parameters such as inducer concentration, host’s proteases and precipitating agent using Outer membrane protein A (OmpA). For efficient expression and secretion of OmpA, pSEC:OmpA vector was successfully constructed. To circumvent the troubles encountered during detection of expressed OmpA, the precipitating agent was switched from TCA to methanol. Nevertheless, detection was achieved accompanied by degraded protein products. Speculating the accountability of observed degradation at higher inducer concentration, different nisin concentrations were evaluated. Lower nisin concentrations were found desirable for optimum expression of OmpA. Consistently observed degradation was eliminated by incorporation of protease inhibitor cocktail which inhibits intracellular proteases and expression in VEL1153 (NZ9000 ΔhtrA) strain which inhibits extracellular protease leading to optimum expression of OmpA. Versatility and complexity of NICE system in L. lactis requires fine-tuning of target protein specific parameters for optimum expression.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-015-0556-2) contains supplementary material, which is available to authorized users.     

A comprehensive review on pharmacological properties and biotechnological aspects of Genus <Emphasis Type="Italic">Chlorophytum</Emphasis>

Genus Chlorophytum Ker Gawl secures its position chiefly as commercial plants with a wide range of applications, right from pharmaceutical to ornamental, and with a promising economical return also. Few species of this genus are now enlisted under “threatened plant category” due to rash harvesting from its wild habitat, as it is utilized extensively in various industries. Great challenges are associated with its conventional propagation approach. The accomplishment and rapidity in the propagation of few species of Chlorophytum have constantly been a key concern for farmers and researchers. In this regard, in vitro propagation is an efficient technique to triumph over regeneration-associated problems. Available literature was surveyed rigorously to extract the information on pharmacological utilities and recent advancements in in vitro regeneration of genus Chlorophytum. Since 1990s to till now, a number of efforts were made in different aspects of Chlorophytum under both in vitro and ex vitro conditions. Current review intends to provide a comprehensive overview of important properties and biotechnological aspects, viz. bioactive constituents and inherent properties of such as aphrodisiac potential, anti-diabetic, anti-microbial, anti-tumor and anti-oxidant, and in vitro production of genus Chlorophytum. Conclusively, proposed article is an attempt to provide overall update of various studies conducted with members of Chlorophytum genus that will possibly be helpful in proper, fullest and sustainable utilization of this important group.     

Tomato Fruits Show Wide Phenomic Diversity but Fruit Developmental Genes Show Low Genomic Diversity

Domestication of tomato has resulted in large diversity in fruit phenotypes. An intensive phenotyping of 127 tomato accessions from 20 countries revealed extensive morphological diversity in fruit traits. The diversity in fruit traits clustered the accessions into nine classes and identified certain promising lines having desirable traits pertaining to total soluble salts (TSS), carotenoids, ripening index, weight and shape. Factor analysis of the morphometric data from Tomato Analyzer showed that the fruit shape is a complex trait shared by several factors. The 100% variance between round and flat fruit shapes was explained by one discriminant function having a canonical correlation of 0.874 by stepwise discriminant analysis. A set of 10 genes (ACS2, COP1, CYC-B, RIN, MSH2, NAC-NOR, PHOT1, PHYA, PHYB and PSY1) involved in various plant developmental processes were screened for SNP polymorphism by EcoTILLING. The genetic diversity in these genes revealed a total of 36 non-synonymous and 18 synonymous changes leading to the identification of 28 haplotypes. The average frequency of polymorphism across the genes was 0.038/Kb. Significant negative Tajima’D statistic in two of the genes, ACS2 and PHOT1 indicated the presence of rare alleles in low frequency. Our study indicates that while there is low polymorphic diversity in the genes regulating plant development, the population shows wider phenotype diversity. Nonetheless, morphological and genetic diversity of the present collection can be further exploited as potential resources in future.     

Intraocular Pressure Reduction Is Associated with Reduced Venous Pulsation Pressure

Purpose

To explore whether alterations in intraocular pressure (IOP) affect vein pulsation properties using ophthalmodynamometric measures of vein pulsation pressure.

Patients and Methods

Glaucoma patients had two retinal vein pulsation pressure (VPP) measurements from upper and lower hemiveins performed by ophthalmodynamometry at least 3 months apart. All subjects had VPP and IOP recorded at two visits, with standard automated perimetry, central corneal thickness (CCT) recorded at the initial visit. Where venous pulsation was spontaneous ophthalmodynamometry could not be performed and VPP was considered equal to IOP. Change in VPP was calculated and binarized with reduction in pressure scored 1 and no change or increase scored as 0. Data analysis used a mixed logistic regression model with change in VPP as response variable and change in IOP, visual field loss (mean deviation), CCT and time interval as explanatory variables.

Results

31 subjects (20 females) with mean age 60 years (sd 11) were examined with change in VPP being significantly associated with change in IOP (odds ratio 1.6/mmHg, 95% CI 1.2 to 2.1 in the glaucoma patients but not suspect patients (p = 0.0005).

Conclusion

Change in VPP is strongly associated with change in IOP such that a reduced intraocular pressure is associated with a subsequent reduction in VPP. This indicates that reduced IOP alters some retinal vein properties however the nature and time course of these changes is not known.     

Tracking dynamics of enzyme activities and their gene expression in <Emphasis Type="Italic">Picrorhiza kurroa</Emphasis> with respect to picroside accumulation

Picrosides, the terpenoids synthesized by Picrorhiza kurroa, have ample usage in medicine. Identification of the regulatory enzymes involved in picroside biosynthesis needs to be explored for improving the level of these secondary metabolites. Current efforts are based on the analysis of secondary metabolism in picroside biosynthesis but its interpretation is limited by the lack of information on the involvement of primary metabolic pathways. The present study investigated the connection of primary metabolic enzymes with the picrosides levels in P. kurroa. The results showed changes in the catalytic activities as well as in the gene expression profiles of hexokinase, pyruvate kinase, isocitrate dehydrogenase, malate dehydrogenase, and NADP⁺-malic enzyme in congruence with picroside-I content under different conditions of P. kurroa growth, which indicates the role of these enzymes in the accumulation of picrosides. The significant correlation coefficients (p?<?0.05) observed between gene expression and enzyme activity underline the role of integrative studies for a better understanding of connecting links between metabolic pathways leading to picroside biosynthesis. This is apparently the first report on the involvement of glycolytic and TCA cycle enzymes in the accumulation of picrosides in P. kurroa.     

Modulation of Picroside-I Biosynthesis in Grown Elicited Shoots of <Emphasis Type="Italic">Picrorhiza kurroa</Emphasis> In Vitro

Elicitors are considered as biostimulants for growth improvement and enhancement of secondary metabolite content. To date, only seaweed extract (SWE) powder has been studied for its effect on picroside-I (P-I) production in in vitro grown Picrorhiza kurroa plants. However, little is known at the molecular level about P-I production in P. kurroa plants upon SWE treatment. Here, we investigated the relative effects of supplying different elicitors including methyl jasmonate (MeJa), sodium nitroprusside (SNP), and abscisic acid (ABA) with SWE on plant growth and P-I production in addition to their effects at the molecular level reflecting the metabolic status of P-I biosynthesis. Our results indicated that only SWE, ABA, and SNP stimulated P-I production by 2.60-, 2.01-, and 1.35-fold, respectively, whereas MeJa decreased P-I content. Interestingly, SWE modulated all four integrating secondary metabolic pathways, covering almost all critical steps in the methylerythritol phosphate (MEP), mevalonate (MVA), iridoid, and phenylpropanoid pathways to stimulate P-I biosynthesis. SNP targeted the MVA/MEP pathways in conjunction with the iridoid pathway, whereas ABA modulated the phenylpropanoid pathway to increase the P-I content in P. kurroa. This is apparently the first report on treatment of different elicitors in in vitro grown P. kurroa plants for eliciting P-I content and exploring the role of different elicitors at the molecular level.