The function and structural influence of selective relaxed constraint at functional intracellular loop3 of 5-HT(1A) serotonin-1 receptor family

Superoxide dismutases (SODs) are metalloenzymes that represent one important line of defense against reactive oxygen species (ROS). In this paper, two novel SOD genes, MdSOD1 and MdSOD2, which putatively encode 261 and 214 amino acid residues respectively were identified and characterized from the housefly Musca domestica. The high similarity of MdSOD1 and MdSOD2 with SODs from other organisms indicated that they should be two new members of the SOD family. qPCR exhibited a universal expression of MdSOD1 and MdSOD2 detected in various tissues of housefly larva, including the fat body, gut, hemocyte and epidermis. Expression profiling reveals that MdSOD1 and MdSOD2 can be induced significantly via not only heat shock and cadmium (Cd) stress but also Escherichia coli and Staphylococcus aureus challenge. The two genes were cloned into the prokaryotic expression vector pET-28a to obtain the fusion proteins rMdSOD1 and rMdSOD2. Between them, the activity of rMdSOD2 was found by visual assay methods. ESI-LC-MS/MS analysis showed that three peptide fragments of the protein rMdSOD2 were identical to the corresponding sequence of M. domestica MdSOD2. MdSOD1 and MdSOD2 in housefly larvae were abrogated by feeding bacteria expressing dsRNA. High mortalities were observed in the larvae treated with dsRNA of SODs at heat shock, Cd stress and bacterial invasion. This phenomenon indicated that MdSOD1 and MdSOD2 are related to the survival of M. domestica under stress. This may provide new insights into the role of the two SOD genes in protecting M. domestica against both stress and bacterial invasion.     

Insight into pattern of codon biasness and nucleotide base usage in serotonin receptor gene family from different mammalian species

5-HT (5-Hydroxy-tryptamine) or serotonin receptors are found both in central and peripheral nervous system as well as in non-neuronal tissues. In the animal and human nervous system, serotonin produces various functional effects through a variety of membrane bound receptors. In this study, we focus on 5-HT receptor family from different mammals and examined the factors that account for codon and nucleotide usage variation. A total of 110 homologous coding sequences from 11 different mammalian species were analyzed using relative synonymous codon usage (RSCU), correspondence analysis (COA) and hierarchical cluster analysis together with nucleotide base usage frequency of chemically similar amino acid codons. The mean effective number of codon (ENc) value of 37.06 for 5-HT(6) shows very high codon bias within the family and may be due to high selective translational efficiency. The COA and Spearman's rank correlation reveals that the nucleotide compositional mutation bias as the major factors influencing the codon usage in serotonin receptor genes. The hierarchical cluster analysis suggests that gene function is another dominant factor that affects the codon usage bias, while species is a minor factor. Nucleotide base usage was reported using Goldman, Engelman, Stietz (GES) scale reveals the presence of high uracil (>45%) content at functionally important hydrophobic regions. Our in silico approach will certainly help for further investigations on critical inference on evolution, structure, function and gene expression aspects of 5-HT receptors family which are potential antipsychotic drug targets.     

Targeted therapy for cancer using pH-responsive nanocarrier systems

Most of the conventional chemotherapeutic agents used against cancer have poor efficacy. An approach to improve the efficacy of cancer chemotherapy is the development of carrier systems that can be triggered to release the anticancer drug in response to extracellular or intracellular chemical stimuli. To this end, pH-responsive nanocarriers have been developed to target drugs either to the slightly acidic extracellular fluids of tumor tissue or, after endocytosis, to the endosomes or lysosomes within cancer cells. These systems can release the drug by specific processes after accumulation in tumor tissues via the enhanced permeability and retention (EPR) effect or they can release the drugs in endosomes or lysosomes by pH-controlled hydrolysis after they are taken up by the cell via the endocytic pathway. This strategy facilitates the specific delivery of the drug while reducing systemic side-effects with high potential for improving the efficacy of cancer chemotherapy.     

Netrin-1 in the developing enteric nervous system and colorectal cancer

Netrin-1 is a well-characterised chemoattractant involved in neuronal guidance in the developing enteric nervous system (ENS), but it is also a regulator of tumorigenesis. Two of its well-characterised receptors, deleted in colorectal cancer (DCC) and uncoordinated-5 homolog (UNC-5H), belong to a family of dependence receptors that transmit either pro- or anti-apoptosis signals depending on the availability of ligand, in this case netrin-1. This review summarises these two effects of netrin-1 and highlights the additional research needed information about to allow better utilisation of netrin-1 as a therapeutic target for axonal regeneration in the context of colorectal cancer.     

Targeting TNF superfamily members for therapeutic intervention in rheumatoid arthritis

Rheumatoid arthritis (RA) is an inflammatory disease is one of the most serious medical problems, affecting ～1% of all people worldwide, irrespective of race. The disease is autoimmune in nature and characterized by chronic inflammation of the synovial tissues in multiple joints that leads to joint destruction. Although T cells are central players in RA development, B cells are required for full penetrance of disease largely via their production of autoantibodies against Fc domain of IgG rheumatoid factor (RF). Treatment options for RA are limited and if any, are inadequate due to associated side effects. Members of the tumor necrosis factor (TNF) superfamily play important roles in a number of autoimmune diseases, including RA. In this review, we briefly summarize key features of the superfamily, we will consider how the well-characterized members concerned with immune regulation are coordinated and their roles in rheumatoid arthritis.     

Effect of different levels of selenium supplementation on growth rate, nutrient utilization, blood metabolic profile, and immune response in lambs

Eighteen male lambs (8-9 months of age, 25.00 +/- 0.90 kg body weight) were divided into three groups of six animals in each and fed a total mixed ration (TMR) containing concentrate mixture (30% maize grain, 27% soybean meal, 40% wheat bran, 2% mineral mixture, and 1% common salt) and wheat straw in 65:35 ratio and supplemented with selenium (Se) as sodium selenite at 0 (T1, control), 0.15 (T2), and 0.30 ppm (T3) levels. Experimental feeding was done for a period of 90 days including a 6-day metabolism trial. To assess the growth performance, lambs were weighed every 15 days throughout the experimental period. All the lambs were intramuscularly inoculated with a single dose (2 ml) of haemorrhagic septicaemia oil adjuvant vaccine on 0 day to evaluate the humoral immune response. Blood samples were collected on 0 day and thereafter at 30 days interval. Results revealed that supplementation of Se both at 0.15 and 0.30 ppm levels had no significant (P > 0.05) effect on intake and digestibility of dry matter, organic matter, crude protein (CP), ether extract, neutral detergent fiber, acid detergent fiber, and hemicellulose; balances of calcium and phosphorus; and level and intake of digestible CP and total digestible nutrients. Se supplementation also had no significant (P > 0.05) effect on the levels of serum total cholesterol, total protein, albumin, globulin, albumin/globulin ratio, tri-iodothyronine (T(3)), thyroxine (T(4)), and T(4)/T(3) ratio; and serum glutamate oxaloacetate transaminase and serum glutamate pyruvate transaminase enzyme activity in the lambs. However, there was a significant (P < 0.05) increase in the plasma Se levels, red blood cell glutathione peroxidase enzyme activity, and humoral immune response in both the Se-supplemented groups. Feed (TMR) required per kilogram gain was less by 11.1% and 16.5% in groups T2 and T3, respectively, as compared to control (T1) group. Average daily gain was highest (108.5 g) in group T3, followed by group T2 (98.2 g), and lowest (89.06 g) in the control group (T1). These results indicated that supplementation of 0.15 and 0.3 ppm Se in the diet (having 0.19 ppm Se) of lambs significantly improves their immune response and antioxidant status.     

Evaluation of Copper Supplementation to Control <Emphasis Type="Italic">Haemonchus contortus</Emphasis>Infections of Sheep in Sweden

A pen study was conducted to assess the effect of providing daily copper mineral supplement, or copper wire particle (COWP) capsules, on established or incoming mixed nematode infections in young sheep. For lambs with established (6 week old) infections, COWP resulted in 97% and 56% reduction of the adult and early L4 stages of H. contortus, respectively, compared with controls (p < 0.001). Additionally there was a 74% reduction in Teladorsagia circumcincta infections in the COWP lambs compared with controls (p < 0.01). However, no effect was observed when COWP were given at the commencement of a larval dosing period of 6 weeks. There was no significant effect of copper mineral supplement (given at the recommended rate to prevent Cu deficiency) on either established, or developing parasite infections. In addition, a field trial was conducted on a commercial farm to assess the effects of COWP in the management of recurrent H. contortus infections, but lack of parasites during the grazing season prevented an adequate assessment from being made. These results indicate that there is little, if any, benefit from a parasite control standpoint in recommending copper therapy, specifically to control parasites in Swedish sheep flocks.     

Phosphatases modulate transmission and serotonin facilitation at synapses: studies with the inhibitor okadaic acid.

We examined the role of phosphatases in synaptic transmission using the permeant phosphatase inhibitor okadaic acid (OA). In the crayfish neuromuscular junction (NMJ), postsynaptic effects including increases in input resistance occurred at doses greater than 5 microM OA. At lower doses (0.5-5 microM) the effects were solely presynaptic and transmitter release increased over three-fold despite small reductions in amplitude and duration of presynaptic action potentials. Potentiating effects of serotonin on transmitter release, which depend on phosphorylation, were increased by OA. Frequency facilitation was reduced but its decay was not affected. In frog NMJs, OA increased spontaneous and evoked release two-fold through presynaptic mechanisms. An inactive analog of OA, OA tetra-acetate, had no effect on transmitter release at frog and crayfish NMJ. Therefore, phosphatases have a strong modulating influence on synaptic transmission.