Exploring the potential of drug repurposing for treating depression.

Researchers are interested in drug repurposing or drug repositioning of existing pharmaceuticals because of rising costs and slower rates of new medication development. Other investigations that authorized these treatments used data from experimental research and off-label drug use. More research into the causes of depression could lead to more effective pharmaceutical repurposing efforts. In addition to the loss of neurotransmitters like serotonin and adrenaline, inflammation, inadequate blood flow, and neurotoxins are now thought to be plausible mechanisms. Because of these other mechanisms, repurposing drugs has resulted for treatment-resistant depression. This chapter focuses on therapeutic alternatives and their effectiveness in drug repositioning. Atypical antipsychotics, central nervous system stimulants, and neurotransmitter antagonists have investigated for possible repurposing. Nonetheless, extensive research is required to ensure their formulation, effectiveness, and regulatory compliance.

Phage for treatment of Vibrio cholerae infection.

Bacteriophages (or "phages") are ubiquitous and the amplest biological entities on our planet. It is a natural enemy of bacteria. Cholera is one of the most known diseases to cause multiple pandemics around the world, killing millions of people. The pathogen of cholera is Vibrio species. Up until the emergence of multidrug resistance, preventive therapeutics like antibiotics were the most effective means of battling bacteria. Globally, one of the most significant challenges in treating microbial infections is the development of drug-resistant strains. Based on their antibacterial properties and unique characteristics, phages are being comprehensively evaluated taxonomically. Moreover, phage-based vaccination is evolving as one of the most encouraging preventive approaches. Due to this, its related research got remarkable recognition. However, due to the rapid emergence of bacterial resistance to antibiotics, the use of phages (phage therapy) could be a major motive for research because the most promising solution lies in bacteriophages. This chapter briefly highlights the promising use of bacteriophages to combat Vibrio-related infectious diseases.

Epigenetics in renal diseases.

With aging, prevalence of obesity, hypertension, diabetes and renal diseases have increased globally. Over the last two decades, the prevalence of renal diseases has been intensely increasing. Renal disease and renal programming are regulated by epigenetic modifications like DNA methylation and histone modifications. Environmental factors have significant role in the pathophysiology of renal disease progression. Understanding the potential of epigenetic regulation of gene expression may be useful in renal disease prognosis, diagnosis and provides novel therapeutic measures. In a nutshell, this chapter talks about the role of epigenetic mechanisms-DNA methylation, histone modification, and noncoding RNA in different renal diseases. These include diabetic kidney disease, diabetic nephropathy, renal fibrosis, etc.

Insight into epigenetics and human diseases.

The most eminent research of the 21st century whirls around the epigenetic and the variability of DNA sequences in humans. The reciprocity between the epigenetic changes and the exogenous factors drives an influence on the inheritance biology and gene expression both inter-generationally and trans-generationally. Chromatin level modifications like DNA methylation, histone modifications or changes in transcripts functions either at transcription level or translational level pave the way for certain diseases or cancer in humans. The ability of epigenetics to explain the processes of various diseases has been demonstrated by recent epigenetic studies. Multidisciplinary therapeutic strategies were developed in order to analyse how epigenetic elements interact with different disease pathways. In this chapter we summarize how an organism may be predisposed to certain diseases by exposure to environmental variables such as chemicals, medications, stress, or infections during particular, vulnerable phases of life, and the epigenetic component may influence some of the diseases in humans.

State-of-the-art techniques to study epigenetics.

The epigenome consists of all the epigenetic alterations like DNA methylation, the histone modifications and non-coding RNAs which change the gene expression and have a role in diseases like cancer and other processes. Epigenetic modifications can control gene expression through variable gene activity at various levels which affects various cellular phenomenon such as cell differentiations, variability, morphogenesis, and the adaptability of an organism. Various factors such as food, pollutants, drugs, stress etc., impact the epigenome. Epigenetic mechanisms mainly involve various post-translational alteration of histones and DNA methylation. Numerous methods have been utilized to study these epigenetic marks. Various histone modifications and binding of histone modifier proteins can be analyzed using chromatin immunoprecipitation (ChIP) which is one of broadly utilized method. Other modified forms of the ChIP have been developed such as reverse chromatin immunoprecipitation (R-ChIP); sequential ChIP (ChIP-re-ChIP) and some high-throughput modified forms of ChIP such as ChIP-seq and ChIP-on-chip. Another epigenetic mechanism is DNA methylation, in which DNA methyltransferases (DNMTs) add a methyl group to the C-5 position of the cytosine. Bisulfite sequencing is the oldest and usually utilized method to measure the DNA methylation status. Other techniques have been established are whole genome bisulfite sequencing (WGBS), methylated DNA immune-precipitation based methods (MeDIP), methylation sensitive restriction enzyme digestion followed by sequencing (MRE-seq) and methylation BeadChip to study the methylome. This chapter briefly discusses the key principles and methods used to study epigenetics in health and disease conditions.

Endocytosis and signaling of 5-HT1A receptor.

The neurotransmitter serotonin (also known as 5-hydroxytryptamine, 5-HT) regulates many important physiological as well as pathological functions in the body like psychoemotional, sensation, blood circulation, food intake, autonomic, memory, sleep, pain, etc. 5-HT binds to its receptor 5-HT1A to initiate GTP exchange at the Gi/o protein, which activates the receptor G protein complex. G protein subunits attach to different effectors and generate various responses, such as inhibition of adenyl cyclase enzyme and regulates the opening of Ca++ and K+ ion channels. Activated signalling cascades activate protein kinase C (PKC) (a second messenger), which further induces the detachment of Gßγ-dependent receptor signaling and leads to 5-HT1A internalization. After internalization, 5-HT1A receptor attaches to the Ras-ERK1/2 pathway. The receptor further trafficks to the lysosome for degradation. Receptor skips the trafficking to the lysosomal compartments and undergoes dephosphorylation. Dephosphorylated receptors now recycled back to the cell membrane. In this chapter, we have discussed the internalization, trafficking and signaling of the 5-HT1A receptor.

Emerging tools for studying receptor endocytosis and signaling.

Ligands, agonists, or antagonists use receptor-mediated endocytosis (RME) to reach their intracellular targets. After the internalization of ligand-receptor complexes, it traffics through different subcellular organelles such as early endosome, recycling endosome, lysosome, etc. Further, after the ligand binding to the receptor, different second messengers are generated, such as cGMP, cAMP, IP3, etc. Several methods have been used, such as radioligand binding assay, western blotting, co-immunoprecipitation (co-IP), qRT-PCR, immunofluorescence and confocal microscopy, microRNA/siRNA, and bioassays to understand the various events, such as internalization, subcellular trafficking, signaling, metabolic degradation, etc. This chapter briefly discusses the key principles and methods used to study internalization, subcellular trafficking, signaling, and metabolic degradation of numerous receptors.

Neutralization and Binding Profile of Monoclonal Antibodies Generated Against Influenza A H1N1 Viruses.

Monoclonal antibodies (MAbs) provide scope for the development of better therapeutics and diagnostic tools. Herein, we describe the binding and neutralization profile(s) for a panel of murine MAbs generated against influenza A H1N1 viruses elicited by immunization with pandemic H1 recombinant hemagglutinin (rHA)/whole virus or seasonal H1 rHA. Neutralizing MAbs, MA-2070 and MA-M, were obtained after pandemic A/California/07/2009 (H1N1) virus/rHA immunization(s). Both MAbs reacted specifically with rHA from A/California/07/2009 and A/England/195/2009 in ELISA. MA-2070 bound rHA of A/California/07/2009 with high affinity (KD = 51.36 ± 9.20 nM) and exhibited potent in vitro neutralization (IC50 = 2.50 µg/mL). MA-2070 bound within the stem domain of HA. MA-M exhibited both hemagglutination inhibition (HI, 1.50 µg/mL) and in vitro neutralization (IC50 = 0.66 µg/mL) activity against the pandemic A/California/07/2009 virus and showed higher binding affinity (KD = 9.80 ± 0.67 nM) than MA-2070. MAb, MA-H generated against the seasonal A/Solomon Islands/03/2006 (H1N1) rHA binds within the head domain and bound the seasonal H1N1 (A/Solomon Islands/03/2006 and A/New Caledonia/20/1990) rHAs with high affinity (KD; 0.72-8.23 nM). MA-H showed high HI (2.50 µg/mL) and in vitro neutralization (IC50 = 2.61 µg/mL) activity against the A/Solomon Islands/03/2006 virus. All 3 MAbs failed to react in ELISA with rHA from various strains of H2N2, H3N2, H5N1, H7N9, and influenza virus B, suggesting their specificity for either pandemic or seasonal H1N1 influenza virus. The MAbs reported here may be useful in developing diagnostic assays.

ExcellmiRDB for translational genomics: a curated online resource for extracellular microRNAs.

A large number of studies have suggested extracellular microRNAs (microRNAs in biofluids) as potential noninvasive biomarkers for pathophysiological conditions such as cancer. However, reported differentially expressed signatures of extracellular miRNAs in diseases are not uniformly consistent among studies. Here, we present "ExcellmiRDB", a curated online database that provides integrated information about miRNAs levels in biofluids in a user-friendly way. Although many miRNA databases, including disease-oriented databases, have been launched before, the ExcellmiRDB is so far the only one specialized for storing curated data on miRNA levels in biofluid samples. At present, ExcellmiRDB has 2773 disease-extracellular miRNAs and 1108 biofluid-extracellular miRNAs relationships curated from 108 articles selected from more than 600 surveyed PubMed abstracts. Information about 992 miRNAs, 82 diseases, 21 biofluids, 8 species, 63 normalization reference genes, 5 techniques, 14 GEO profiles accession numbers, 7 human ethnic groups, and 18 compared clinical biomarkers have been provided in the database. A user can query ExcellmiRDB by selecting a disease or a miRNA or a biofluid. Additionally, the database provides two online network graphs to visualize and interact with the content of the database. The first network shows disease-extracellular miRNAs relationships, along with expression patterns and number of articles for a relationship. The second network visualizes biofluid-extracellular miRNAs relationships showing miRNAs spectrum across different types of biofluids. In conclusion, ExcellmiRDB is a new innovative resource for both academic and industrial researchers in translational omics who are developing miRNA biomarkers for noninvasive diagnostic or prognostic technologies. ExcellmiRDB is publicly available on www.excellmirdb.brfjaisalmer.com/.

The acrocallosal syndrome in a neonate with further widening of phenotypic expression.

The presentation of the typical characteristics of the acrocallosal syndrome (ACLS) are hypoplasia/agenesis of corpus callosum, moderate to severe mental retardation, characteristic craniofacial abnormalities, distinctive digital malformation, and growth retardation in a neonate. An Indian neonate presented on day 1 of life (youngest in the literature to be reported) with combination of abnormalities consistent with the acrocallosal syndrome and some additional findings. The baby, born to non-consanguineous, healthy parents, presented with macrocephaly, prominent forehead, hypertelorism, polydactyly of the hands and feet, duplication of hallux, hypotonia, recurrent cyanotic episodes, rib anomalies, dextro-positioning of heart, and delayed fall of umbilical cord. As the mode of inheritance of ACLS is autosomal recessive, the risk of recurrence is 25%. Genetic counselling is of prime importance, Polydactyly, and central nervous system malformations can be detected by ultrasonography in the second trimester, but due to variability of presentation, prenatal diagnosis may not always be possible.

Role of Swi6/HP1 self-association-mediated recruitment of Clr4/Suv39 in establishment and maintenance of heterochromatin in fission yeast.

Swi6/HP1, an evolutionarily conserved protein, is critical for heterochromatin assembly in fission yeast and higher eukaryotes. In fission yeast, histone deacetylation by histone deacetylases is thought to be followed by H3-Lys-9 methylation by the histone methyltransferase Clr4/Suv39H1. H3-Lys-9-Me2 interacts with the chromodomain of Swi6/HP1. Swi6/HP1 is thought to act downstream of Clr4/Suv39, and further self-association of Swi6/HP1 is assumed to stabilize the heterochromatin structure. Here, we show that the self-association-defective mutant of Swi6 does not interact with Clr4. It not only fails to localize to heterochromatin loci but also interferes with heterochromatic localization of H3-Lys-9-Me2 (and thereby Clr4) and the endogenous Swi6 in a dominant negative manner. Thus, self-association of Swi6/HP1 helps in binding to and recruitment of Clr4 and thereby in establishment and maintenance of heterochromatin by a concerted rather than a sequential mechanism.

Interaction of APC/C-E3 ligase with Swi6/HP1 and Clr4/Suv39 in heterochromatin assembly in fission yeast.

Heterochromatin assembly in fission yeast is initiated by binding of Swi6/HP1 to the Lys-9-dimethylated H3 followed by spreading via cooperative recruitment of Swi6/HP1. Recruitment of Cohesin by Swi6/HP1 further stabilizes the heterochromatin structure and integrity. Subsequently, polyubiquitylation of Cut2 by anaphase-promoting complex-cyclosome (APC/C)-ubiquitin-protein isopeptide ligase (E3 ligase) followed by degradation of Cut2 releases Cut1, which cleaves the Rad21 subunit of Cohesin, facilitating sister chromatid separation during mitosis. Here, we demonstrate a surprising role of APC/C in assembly of heterochromatin and silencing at mating type, centromere, and ribosomal DNA loci. Coincidentally with the loss of silencing, recruitment of Swi6, H3-Lys-9-Me2, and Clr4 at dg-dh repeats at cen1 and the K region of mat locus is abrogated in mutants cut4, cut9, and nuc2. Surprisingly, both Cut4 and Cut9 are also highly enriched at these regions in wild type and depleted in swi6Delta mutant. Cut4 and Cut9 interact directly with Swi6/HP1 and Clr4, whereas the mutant Cut4 does not, suggesting that a direct physical interaction of APC subunits Cut4 and Cut9 with Swi6 and Clr4 is instrumental in heterochromatin assembly. The silencing defect in APC mutants is causally related to ubiquitylation activity of APC-E3 ligase. Like swi6 mutant, APC mutants are also defective in Cohesin recruitment and exhibit defects like lagging chromosomes, chromosome loss, and aberrant recombination in the mat region. In addition, APC mutants exhibit a bidirectional expression of dh repeats, suggesting a role in the RNA interference pathway. Thus, APC and heterochromatin proteins Swi6 and Clr4 play a mutually cooperative role in heterochromatin assembly, thereby ensuring chromosomal integrity, inheritance, and segregation during mitosis and meiosis.