Ferulic acid in the treatment of post‐diabetes testicular damage: relevance to the down regulation of apoptosis correlates with antioxidant status via modulation of TGF‐β1, IL‐1β and Akt signalling

The aim of this study was to investigate the protective effect of ferulic acid at different doses (50 mg kg^?1 alternative day and 50 mg kg^?1 daily) on the streptozotocin (STZ)‐induced post‐diabetes rat testicular damage. Diabetes was induced by a single intraperitoneal injection of STZ (50 mg/kg). Rats treated with ferulic acid were given once a day orally for 10 weeks, starting 3 days after STZ injection. Testis tissue and blood samples were collected for investigating biochemical analysis, antioxidant status, sperm parameters, and histopathological, immunohistochemical and apoptotic studies. Treatment with ferulic acid to diabetic rats significantly improved the body weight, testis weight, serum insulin level, serum testosterone level and sperm parameters (viability, motility and count). Histopathological study also revealed that ferulic acid‐treated diabetic rats showed an improved histological appearance. Our data indicated that significant reduction in the activity of apoptosis by using terminal deoxyuridine triphosphate nick end‐labelling and reduced expression of transforming growth factor‐β1 and interleukin‐1β in the testis tissue of ferulic acid‐treated diabetic rats. Conversely, it was also revealed that ferulic acid‐treated diabetic rats markedly enhanced the serine/threonine protein kinase protein expression in the testis tissue. Our result suggests that ferulic acid inhibits testicular damage in diabetic rats by declining oxidative stress. Copyright © 2013 John Wiley & Sons, Ltd.     

Musa nagalandiana sp. nov. (Musaceae) from Nagaland,northeast India

Musa nagalandiana S. Dey & Gogoi, a new species of Musa sect. Musa, is described and illustrated from Zunheboto district, Nagaland, India based on morphological characteristics observed in the field. The new species is rare in the wild and found in tropical semi‐evergreen forest on the bank of the river Doyang, in Zunheboto district of Nagaland. A key to M. nagalandiana and related taxa is provided.     

Pathogenesis of primary defects in mitochondrial ATP synthesis

Maternally inherited mutations in the mtDNA-encoded ATPase 6 subunit of complex V (ATP synthase) of the respiratory chain/oxidative phosphorylation system are responsible for a subgroup of severe and often-fatal disorders characterized predominantly by lesions in the brain, particularly in the striatum. These include NARP (neuropathy, ataxia, and retinitis pigmentosa), MILS (maternally inherited Leigh syndrome), and FBSN (familial bilateral striatal necrosis). Of the five known pathogenic mutations causing these disorders, four are located at two codons (156 and 217), each of which can suffer mutations converting a conserved leucine to either an arginine or a proline. Based on the accumulating data on both the structure of ATP synthase and the mechanism by which rotary catalysis couples proton flow to ATP synthesis, we propose a model that may help explain why mutations at codons 156 and 217 are pathogenic.     

Metabolite Profiling of a Diverse Collection of Wheat Lines Using Ultraperformance Liquid Chromatography Coupled with Time-of-Flight Mass Spectrometry

Genetic differences among major types of wheat are well characterized; however, little is known about how these distinctions affect the small molecule profile of the wheat seed. Ethanol/water (65% v/v) extracts of seed from 45 wheat lines representing 3 genetically distinct classes, tetraploid durum (Triticum turgidum subspecies durum) (DW) and hexaploid hard and soft bread wheat (T. aestivum subspecies aestivum) (BW) were subjected to ultraperformance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-TOF-MS). Discriminant analyses distinguished DW from BW with 100% accuracy due to differences in expression of nonpolar and polar ions, with differences attributed to sterol lipids/fatty acids and phospholipids/glycerolipids, respectively. Hard versus soft BW was distinguished with 100% accuracy by polar ions, with differences attributed to heterocyclic amines and polyketides versus phospholipid ions, respectively. This work provides a foundation for identification of metabolite profiles associated with desirable agronomic and human health traits and for assessing how environmental factors impact these characteristics.     

Screening, identification, and characterization of mechanistically diverse inhibitors of the Mycobacterium tuberculosis enzyme, pantothenate kinase (CoaA)

The authors describe the discovery of anti-mycobacterial compounds through identifying mechanistically diverse inhibitors of the essential Mycobacterium tuberculosis (Mtb) enzyme, pantothenate kinase (CoaA). Target-driven drug discovery technologies often work with purified enzymes, and inhibitors thus discovered may not optimally inhibit the form of the target enzyme predominant in the bacterial cell or may not be available at the desired concentration. Therefore, in addition to addressing entry or efflux issues, inhibitors with diverse mechanisms of inhibition (MoI) could be prioritized before hit-to-lead optimization. The authors describe a high-throughput assay based on protein thermal melting to screen large numbers of compounds for hits with diverse MoI. Following high-throughput screening for Mtb CoaA enzyme inhibitors, a concentration-dependent increase in protein thermal stability was used to identify true binders, and the degree of enhancement or reduction in thermal stability in the presence of substrate was used to classify inhibitors as competitive or non/uncompetitive. The thermal shift-based MoI assay could be adapted to screen hundreds of compounds in a single experiment as compared to traditional biochemical approaches for MoI determination. This MoI was confirmed through mechanistic studies that estimated K(ie) and K(ies) for representative compounds and through nuclear magnetic resonance-based ligand displacement assays.     

MicroRNAs overexpressed in growth-restricted rat skeletal muscles regulate the glucose transport in cell culture targeting central TGF-β factor SMAD4

The micro-array profiling of micro-RNA has been performed in rat skeletal muscle tissues, isolated from male adult offspring of intrauterine plus postnatal growth restricted model (IPGR). Apparently, the GLUT4 mRNA expression in male sk. muscle was found to be unaltered in contrast to females. The over-expression of miR-29a and miR-23a in the experimental group of SMSP (Starved Mother Starved Pups) have been found to regulate the glucose transport activity with respect to their control counterparts CMCP (Control Mother Control Pups) as confirmed in rat L6 myoblast-myocyte cell culture system. The ex-vivo experimentation demonstrates an aberration in insulin signaling pathway in male sk. muscle that leads to the localization of the membrane-bound Glut4 protein. We have identified through a series of experiments one important protein factor SMAD4, a co-SMAD critical to the TGF-beta signaling pathway. This factor is targeted by miR-29a, as identified in an in vitro reporter-assay system in cell-culture experiment. The other micro-RNA, miR-23a, targets SMAD4 indirectly that seems to be critical in regulating insulin-dependent glucose transport activity. MicroRNA mimics, inhibitors and siRNA studies indicate the role of SMAD4 as inhibitory for glucose transport activities in normal physiological condition. The data demonstrate for the first time a critical function of microRNAs in fine-tuning the regulation of glucose transport in skeletal muscle. Chronic starved conditions (IPGR) in sk. muscle up-regulates microRNA changing the target protein expression patterns, such as SMAD4, to alter the glucose transport pathways for the survival. The innovative outcome of this paper identifies a critical pathway (TGF-beta) that may act negatively for the mammalian glucose transport machinery.     

DNA binding activity of Helicobacter pylori DnaB helicase: the role of the N-terminal domain in modulating DNA binding activities

Replicative helicases are major motor proteins essential for chromosomal DNA replication in prokaryotes. Usually hexameric in solution, their DNA binding property must have different roles at stages ranging from the loading onto a branched structure at initiation from the origin to the highly processive translocation during elongation. Here, we have analysed the DNA binding activity of Helicobacter pylori (Hp) replicative helicase, DnaB. The results indicate that while the C-terminal region is important for its DNA binding activity, the N-terminus appears to dampen the protein's affinity for DNA. The masking activity of the N-terminus does not require ATP or hexamerization of HpDnaB and can be overcome by deleting the N-terminus. It can also be neutralized by engaging the N-terminus in an interaction with a partner like the C-terminus of DnaG primase. The inhibitory effect of the N-terminus on DNA binding activity is consistent with the 3D homology model of HpDnaB. Electron microscopy of the HpDnaB-ssDNA complex showed that HpDnaB preferentially bound at the ends of linear ssDNA and translocated along the DNA in the presence of ATP. These results provide an insight into the stimulatory and inhibitory effects of different regions of HpDnaB on DNA binding activities that may be central to the loading and translocation functions of DnaB helicases.     

DDA-Based Simulation of UV?Cvis Extinction Spectra of Ag Nanorods Synthesized Through Seed-Mediated Growth Process

Present investigation demonstrates a very simple seed-mediated route for the synthesis of silver nanorods in aqueous solution. Central to the concept of seed-mediated growth of nanoparticles is that small nanoparticle seeds serve as nucleation centres to grow nanoparticles to a desired size and shape. Hydroxypropyl methyl cellulose (HPMC) has been used as soft template for one-dimensional growth of silver particles. Morphological, structural and spectral changes that are associated with the seed-mediated growth of the nanoparticles in presence of HPMC are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of UV–vis extinction spectra of our synthesized silver nanorods has been carried out using discrete dipole approximation methodology. The broad red-shifted longitudinal extinction band of green-coloured silver sol has been explained, due to the presence of silver nanorods of different aspect ratios.     

Expression patterns of MDA-9/syntenin during development of the mouse embryo

Melanoma differentiation associated gene-9 (MDA-9)/syntenin is a PDZ domain-containing adaptor protein involved in multiple diverse cellular processes including organization of protein complexes in the plasma membrane, intracellular trafficking and cell surface targeting, synaptic transmission, and cancer metastasis. In the present study, we analyzed the expression pattern of MDA-9/syntenin during mouse development. MDA-9/syntenin was robustly expressed with tight regulation of its temporal and spatial expression during fetal development in the developing skin, spinal cord, heart, lung and liver, which are regulated by multiple signaling pathways in the process of organogenesis. Recent studies also indicate that MDA-9/syntenin is involved in the signaling pathways crucial during development such as Wnt, Notch and FGF. Taken together, these results suggest that MDA-9/syntenin may play a prominent role during normal mouse development in the context of cell proliferation as well as differentiation through modulating multiple signaling pathways as a crucial adaptor protein. Additionally, temporal regulation of MDA-9/syntenin expression may be required during specific stages and in specific tissues during development.     

Gene Transfection in High Serum Levels: Case Studies with New Cholesterol Based Cationic Gemini Lipids

Background

Six new cationic gemini lipids based on cholesterol possessing different positional combinations of hydroxyethyl (-CH₂CH₂OH) and oligo-oxyethylene -(CH₂CH₂O)_n- moieties were synthesized. For comparison the corresponding monomeric lipid was also prepared. Each new cationic lipid was found to form stable, clear suspensions in aqueous media.

Methodology/Principal Findings

To understand the nature of the individual lipid aggregates, we have studied the aggregation properties using transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential measurements and X-ray diffraction (XRD). We studied the lipid/DNA complex (lipoplex) formation and the release of the DNA from such lipoplexes using ethidium bromide. These gemini lipids in presence of a helper lipid, 1, 2-dioleoyl phophatidyl ethanol amine (DOPE) showed significant enhancements in the gene transfection compared to several commercially available transfection agents. Cholesterol based gemini having -CH₂-CH₂-OH groups at the head and one oxyethylene spacer was found to be the most effective lipid, which showed transfection activity even in presence of high serum levels (50%) greater than Effectene, one of the potent commercially available transfecting agents. Most of these geminis protected plasmid DNA remarkably against DNase I in serum, although the degree of stability was found to vary with their structural features.

Conclusions/Significance

-OH groups present on the cationic headgroups in combination with oxyethylene linkers on cholesterol based geminis, gave an optimized combination of new genera of gemini lipids possessing high transfection efficiency even in presence of very high percentage of serum. This property makes them preferential transfection reagents for possible in vivo studies.