Glucosinolates in seeds of Neslia paniculata

The glucosinolate fraction in seeds of Neslia paniculata (L.) Desv., subsp. thracica (Velen.) Bornmüller, (Cruciferae), has been isolated and subjected to enzymic hydrolysis. The isothiocyanates thus produced have been separated and identified as cheirolin (II), (R)-9-methylsulfinylnonyl (III), (R)-10-methylsulfinyldecyl (IV), and (R)-11-methylsulfinylundecyl isothiocyanate (V), the last of which has not been previously encountered as a natural compound.     

Lipodystrophies: Disorders of adipose tissue biology

The adipocytes synthesize and store triglycerides as lipid droplets surrounded by various proteins and phospholipids at its surface. Recently, the molecular basis of some of the genetic syndromes of lipodystrophies has been elucidated and some of these genetic loci have been found to contribute to lipid droplet formation in adipocytes. The two main types of genetic lipodystrophies are congenital generalized lipodystrophy (CGL) and familial partial lipodystrophy (FPL). So far, three CGL loci: 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), Berardinelli–Seip Congenital Lipodystrophy 2 (BSCL2) and caveolin 1 (CAV1) and four FPL loci: lamin A/C (LMNA), peroxisome proliferator-activated receptor γ (PPARG), v-AKT murine thymoma oncogene homolog 2 (AKT2) and zinc metalloprotease (ZMPSTE24), have been identified. AGPAT2 plays a critical role in the synthesis of glycerophospholipids and triglycerides required for lipid droplet formation. Another protein, seipin (encoded by BSCL2 gene), has been found to induce lipid droplet fusion. CAV1 is an integral component of caveolae and might contribute towards lipid droplet formation. PPARγ and AKT2 play important role in adipogenesis and lipid synthesis. In this review, we discuss and speculate about the contribution of various lipodystrophy genes and their products in the lipid droplet formation.     

The application of multiplex fluorimetric sensor for the analysis of flavonoids content in the medicinal herbs family Asteraceae,Lamiaceae, Rosaceae

Background

The aim of our research work was to quantify total flavonoid contents in the leaves of 13 plant species family Asteraceae, 8 representatives of family Lamiaceae and 9 plant species belonging to family Rosaceae, using the multiplex fluorimetric sensor. Fluorescence was measured using optical fluorescence apparatus Multiplex(R) 3 (Force-A, France) for non-destructive flavonoids estimation. The content of total flavonoids was estimated by FLAV index (expressed in relative units), that is deduced from flavonoids UV absorbing properties.

Results

Among observed plant species, the highest amount of total flavonoids has been found in leaves of Helianthus multiflorus (1.65 RU) and Echinops ritro (1.27 RU), Rudbeckia fulgida (1.13 RU) belonging to the family Asteraceae. Lowest flavonoid content has been observed in the leaves of marigold (Calendula officinalis) (0.14 RU) also belonging to family Asteraceae. The highest content of flavonoids among experimental plants of family Rosaceae has been estimated in the leaves of Rosa canina (1.18 RU) and among plant species of family Lamiaceae in the leaves of Coleus blumei (0.90 RU).

Conclusions

This research work was done as pre-screening of flavonoids content in the leaves of plant species belonging to family Asteraceae, Lamiaceae and Rosaceae. Results indicated that statistically significant differences (P > 0.05) in flavonoids content were observed not only between families, but also among individual plant species within one family.     

The methylation status of FBXW7 beta-form correlates with histological subtype in human thymoma

FBXW7 is reported to be a tumor suppressor gene, and the functional inactivation of FBXW7 has been reported in various human tumors. In this study, we investigated the FBXW7 gene in human thymoma; although no mutations were evident, a significantly high frequency of methylation in the FBXW7 β-form promoter was observed in types B1 or higher (P = 0.014). We propose a novel mechanism for the pathogenesis of thymoma by FBXW7 β-form and hypothesize that expressional suppression plays an important role in the malignant potential of thymoma.     

SREBF1 links lipogenesis to mitophagy and sporadic Parkinson disease

Mitochondrial quality control has an impact on many diseases, but intense research has focused on the action of 2 genes linked to heritable forms of Parkinson disease (PD), PINK1 and PARK2/parkin, which act in a common pathway to promote mitophagy. However, criticism has been raised that little evidence links this mechanism to sporadic PD. To gain a greater insight into the mechanisms of PINK1-PARK2 mediated mitophagy, we undertook a genome-wide RNAi screen in Drosophila and human cell models. Strikingly, we discovered several components of the lipogenesis pathway, including SREBF1, playing a conserved role in mitophagy. Our results suggest that lipids influence the stabilization of PINK1 during the initiation of mitophagy. Importantly, SREBF1 has previously been identified as a risk locus for sporadic PD, and thus implicates aberrant mitophagy as contributing to sporadic PD. Our findings suggest a role for lipid synthesis in PINK1-PARK2 mediated mitophagy, and propose a mechanistic link between familial and sporadic PD, supporting a common etiology.     

The complex interactions between host immunity and non-biotrophic fungal pathogens of wheat leaves

Significant progress has been made in elucidating the mechanisms used by plants to recognize pathogens and activate “immune” responses. A “first line” of defense can be triggered through recognition of conserved Pathogen or Microbe Associated Molecular Patterns (PAMPs or MAMPs), resulting in activation of basal (or non-host) plant defenses, referred to as PAMP-triggered immunity (PTI). Disease resistance responses can also subsequently be triggered via gene-for-gene type interactions between pathogen avirulence effector genes and plant disease resistance genes (Avr-R), giving rise to effector triggered immunity (ETI). The majority of the conceptual advances in understanding these systems have been made using model systems, such as Arabidopsis, tobacco, or tomato in combination with biotrophic pathogens that colonize living plant tissues. In contrast, how these disease resistance mechanisms interact with non-biotrophic (hemibiotrophic or necrotrophic) fungal pathogens that thrive on dying host tissue during successful infection, is less clear. Several lines of recent evidence have begun to suggest that these organisms may actually exploit components of plant immunity in order to infect, successfully colonize and reproduce within host tissues. One underlying mechanism for this strategy has been proposed, which has been referred to as effector triggered susceptibility (ETS). This review aims to highlight the complexity of interactions between plant recognition and defense activation towards non-biotrophic pathogens, with particular emphasis on three important fungal diseases of wheat (Triticum aestivum) leaves.     

One-step isolation of sappanol and brazilin from Caesalpinia sappan and their effects on oxidative stress-induced retinal death

Caesalpinia sappan is a well-distributed plant that is cultivated in Southeast Asia, Africa, and the Americas. C. sappan has been used in Asian folk medicine and its extract has been shown to have pharmacological effects. Two homoisoflavonoids, sappanol and brazilin, were isolated from C. sappan by using centrifugal partition chromatography (CPC), and tested for protective effects against retinal cell death. The isolated homoisoflavonoids produced approximately 20-fold inhibition of N-retinylidene-N-retinyl-ethanolamine (A2E) photooxidation in a dose-dependent manner. Of the 2 compounds, brazilin showed better inhibition (197.93 ± 1.59 μM of IC₅₀). Cell viability tests and PI/Hoechst 33342 double staining method indicated that compared to the negative control, sappanol significantly attenuated H₂O₂-induced retinal death. The compounds significantly blunted the up-regulation of intracellular reactive oxygen species (ROS), and sappanol inhibited lipid peroxidation in a concentration-dependent manner. Thus, both compounds represent potential antioxidant treatments for retinal diseases. [BMB Reports 2015; 48(5): 289-294]     

The “tomcat compound” 3-mercapto-3-methylbutanol occurs in the urine of free-ranging leopards but not in African lions or cheetahs

The felid-specific urinary odour compound 3-mercapto-3-methylbutanol and its precursors have been found in several felid species in captivity, but its presence in wild felids has not previously been investigated. We analysed the naturally deposited scent marks from three species of wild, free-ranging big cats in Northern Botswana and found 3-mercapto-3-methylbutanol in four samples of leopard urine (N = 13), but not in lion urine (N = 15) or cheetah urine (N = 6). Individual variation in the presence of the tomcat compound in samples from big cats in the wild may reconcile conflicting results from captive cats.     

A compound isolated from Schisandra chinensis induces apoptosis

Schizandra chinensis has been known to have five predominant tastes: salty, sweet, sour, astringent, and bitter. It has also been shown to have various effects on the cardiovascular system, gastrointestinal system, anti-inflammatory, central nervous system, endocrine system, and stress protect. However, its anti-cancer activity on colon carcinoma HCT-116 cells has not been yet been examined. Thus, in this study, we attempted to isolate a compound from Schisandra chinensis that induced apoptosis in HCT-116 cells. An active compound was found and identified to be Gomisin A. It displayed apoptotic activity through caspase-7 cleavage in colon carcinoma HCT-116 cells. In addition, we further assessed the effects of this compound using long-term survival clonogenic assay with HCT116 cells.     

Ectopic Repo suppresses expression of castor gene in Drosophila central nervous system

The ventral nerve cord (VNC) of the Drosophila embryo is derived from neuroblasts (NBs). NBs divide in a stem cell lineage to generate a series of ganglion mother cells (GMCs), each of which divides once to produce a pair of neurons or glial cells. One of the NB genes, castor (cas), is expressed in a subset of NBs and has never been identified in neurons and the peripheral nervous system; cas plays a role in axonogenesis. But its limited expression along the dorsal-ventral axis within the central nervous system has not been investigated yet. In the present study, we examined the expression patterns of both genes using confocal microscopy to determine the effects of repo mutation on cas expression. Cas was mainly expressed in layers different from repo-expressed layers during early embryogenesis: repo was expressed mostly from deep to mid layers, while cas, from mid to superficial layers. Loss-of-function of repo did not result in an ectopic expression of cas, but rather, a scattering of cas-expressing cells. However, repo gain-of-function mutation caused repression of cas. In addition, repo-expressing cells seemed to block the migration of cas-expressing cells.     

ERK kinase phosphorylates and destabilizes the tumor suppressor FBW7 in pancreatic cancer

F-box and WD repeat domain-containing 7 (FBW7) is the substrate recognition component of the Skp1-Cul1-F-box (SCF) ubiquitin ligase complex and functions as a major tumor suppressor by targeting various oncoproteins for degradation. Genomic deletion or mutation of FBW7 has frequently been identified in many human cancers but not in pancreatic ductal adenocarcinoma. Thus it is important to know how the tumor suppressive function of FBW7 is impaired in pancreatic cancer. In this study, we first observed that low FBW7 expression correlated significantly with ERK activation in pancreatic cancer clinical samples, primarily due to KRAS mutations in pancreatic cancer. We further showed that ERK directly interacted with FBW7 and phosphorylated FBW7 at Thr205, which sequentially promoted FBW7 ubiquitination and proteasomal degradation. Furthermore, the phospho-deficient T205A FBW7 mutant is resistant to ERK activation and could significantly suppress pancreatic cancer cell proliferation and tumorigenesis. These results collectively demonstrate how the oncogenic KRAS mutation inhibits the tumor suppressor FBW7, thus revealing an important function of KRAS mutations in promoting pancreatic cancer progression.     

Homo floresiensis: a cladistic analysis

The announcement of a new species, Homo floresiensis, a primitive hominin that survived until relatively recent times is an enormous challenge to paradigms of human evolution. Until this announcement, the dominant paradigm stipulated that: 1) only more derived hominins had emerged from Africa, and 2) H. sapiens was the only hominin since the demise of Homo erectus and Homo neanderthalensis. Resistance to H. floresiensis has been intense, and debate centers on two sets of competing hypotheses: 1) that it is a primitive hominin, and 2) that it is a modern human, either a pygmoid form or a pathological individual. Despite a range of analytical techniques having been applied to the question, no resolution has been reached. Here, we use cladistic analysis, a tool that has not, until now, been applied to the problem, to establish the phylogenetic position of the species. Our results produce two equally parsimonious phylogenetic trees. The first suggests that H. floresiensis is an early hominin that emerged after Homo rudolfensis (1.86 Ma) but before H. habilis (1.66 Ma, or after 1.9 Ma if the earlier chronology for H. habilis is retained). The second tree indicates H. floresiensis branched after Homo habilis.     

Park7 interacts with p47phox to direct NADPH oxidase-dependent ROS production and protect against sepsis

Inappropriate inflammation responses contribute to mortality during sepsis. Through Toll-like receptors (TLRs), reactive oxygen species (ROS) produced by NADPH oxidase could modulate the inflammation responses. Parkinson disease (autosomal recessive, early onset) 7 (Park7) has a cytoprotective role by eliminating ROS. However, whether Park7 could modulate inflammation responses and mortality in sepsis is unclear. Here, we show that, compared with wild-type mice, Park7^−/− mice had significantly increased mortality and bacterial burdens in sepsis model along with markedly decreased systemic and local inflammation, and drastically impaired macrophage phagocytosis and bacterial killing abilities. Surprisingly, LPS and phorbol-12-myristate-13-acetate stimulation failed to induce ROS and proinflammatory cytokine production in Park7^−/− macrophages and Park7-deficient RAW264.7 cells. Through its C-terminus, Park7 binds to p47^phox, a subunit of the NADPH oxidase, to promote NADPH oxidase-dependent production of ROS. Restoration of Park7 expression rescues ROS production and improves survival in LPS-induced sepsis. Together, our study shows that Park7 has a protective role against sepsis by controlling macrophage activation, NADPH oxidase activation and inflammation responses.     

Sydowia polyspora associated with current season needle necrosis (CSNN) on true fir (Abies spp.)

Current season needle necrosis (CSNN) has been a serious foliage disorder on true fir Christmas trees and bough material in Europe and North America for more than 25 y. Approximately 2–4 weeks after bud break, needles develop chlorotic spots or bands that later turn necrotic. The symptoms have been observed on noble fir (Abies procera), Nordmann fir (A. nordmanniana) and grand fir (A. grandis) on both continents. CSNN was reported as a physiological disorder with unknown aetiology from USA, Denmark, and Ireland, but was associated with the fungus Kabatina abietis in Germany, Austria and Norway. In 2007, a fungus that morphologically resembled K. abietis was isolated from symptomatic needle samples from Nordmann fir from Austria, Denmark, Germany, Norway, and USA. Sequencing of the internal transcribed spacer (ITS) region of ribosomal DNA of these cultures, plus a K. abietis reference culture from Germany (CBS 248.93), resulted in Hormonema dematioides, the imperfect stage of Sydowia polyspora, and thus the taxonomy is further discussed. Inoculation tests on Nordmann fir seedlings and transplants with isolates of S. polyspora from all five countries resulted in the development of CSNN symptoms. In 2009, S. polyspora was also isolated from symptomatic needles from Nordmann fir collected in Slovakia.     

A comparative study: Assessment of the antioxidant system in the invasive green alga Caulerpa racemosa and some macrophytes from the Mediterranean

Reactive oxygen species (ROS) are of great importance in plant metabolism. However, uncontrolled activation of ROS might have deleterious effects in cells. Eleven Mediterranean countries are still under threat of an introduced taxon of Caulerpa racemosa var. cylindracea. In the present study, it has been aimed to compare the antioxidant status of this highly invasive alga with some Mediterranean macrophytes collected in the same habitat. For this purpose, such antioxidant enzyme activities as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and lipid peroxidation (LPO) as well, levels have been determined in C. racemosa, Cystoseira barbata C. Agardh, Padina pavonica (Linnaeus) Thivy and Enteromorpha sp. The highest SOD, CAT, GSH-Px enzyme activities and the lowest LPO level have been measured in the invasive C. racemosa. In conclusion, C. racemosa var. cylindracea seems more tolerant in warring with ROS than the Mediterranean species tested do. These results could partly explain the amazing success of C. racemosa var. cylindracea introduced in the Mediterranean.     

The structure of the O-antigen in the endotoxin of the emerging food pathogen Cronobacter (Enterobacter) muytjensii strain 3270

Strains of the Gram-negative bacterium Cronobacter (formerly known as Enterobacter) sakazakii have been identified as emerging opportunistic pathogens that can cause enterocolitis, bacteraemia, meningitis, and brain abscess, and they have been particularly associated with meningitis in neonates where infant milk formulae have been epidemiologically linked to the disease. A study of the lipopolysaccharides produced by clinical isolates using chemical, 2D ¹H and ¹³C NMR, and MS methods revealed that the O-polysaccharide produced by Cronobactermuytjensii strain 3270, isolated from powdered infant formula from Denmark, was a linear unbranched polymer of a repeating pentasaccharide unit composed of 2-acetamido-2-deoxy-d-galactose (d-GalNAc), 2-acetamido-2-deoxy-d-glucose (d-GlcNAc), 3-acetamido-3-deoxy-d-quinovose (d-Qui3NAc), l-rhamnose (l-Rha), and d-glucuronic acid (d-GlcA) in equimolar ratio, and has the structureThe specific structural characteristics of the O-polysaccharides of C.muytjensii may be of value in the identification and tracking of the bacterial pathogen.     

Insecticidal Toxic Proteins Produced by Photorhabdus luminescens akhurstii,a Symbiont of Heterorhabditis indica

We describe the isolation and characterization of an insect pathogenic bacterium from the entomopathogenic nematode Heterorhabditis indica (Karnataka strain), an isolate from the southern regions of India. The strain has been identified and characterized by phenotypic, biochemical tests and PCR-RFLP analysis of the 16S rRNA gene as Photorhabdus luminescens subsp. akhurstii. The insecticidal toxin complex produced by this bacterium has been purified through a series of steps including ultrafiltration, anion exchange chromatography, and gel filtration chromatography. The toxin consists of two protein complexes of approximately 1,000 kD and was active against the larvae of Spodoptera litura and Galleria mellonella.