Molecular docking analysis of α-Synuclein aggregation with Anle138b.

α-Synuclein aggregation into toxic oligomeric species is central to Parkinson's disease pathogenesis. Anle138b is a recently identified inhibitor of α-synuclein oligomerization showing promise in preclinical studies. This study employed computational approaches to elucidate Anle138b's mechanism of oligomer-specific action. The inhibitory potential of Anle138b against α-synuclein oligomers was evaluated by performing molecular docking studies using AutoDock Tools, followed by their binding pocket analysis. Further, protein-protein docking studies were performed using Hex8.0 to validate the aggregation inhibitory potential of Anle138b. Molecular docking revealed increasing binding affinity of Anle138b against higher order α-synuclein oligomers (dimer to decamer). Anle138b occupied oligomeric cavity and interacted with residues Thr54, Gly73, Val74 and Thr75 across several oligomers. Protein-protein docking showed that Anle138b interferes with α-synuclein decamer formation. These results highlight the oligomer-directed inhibitory mechanism of Anle138b, without hindering the monomeric forms and provide molecular insights to advance its therapeutic development for Parkinson's and related synucleinopathies.

Molecular docking analysis of marine compounds with voltage gated calcium channel for potential anti-epileptic molecules.

Epileptic seizures are directly linked with an anomalous influx of extracellular calcium or sodium anions through voltage-gated channels disturb the chemical and electrical gradients, resulting in seizures or jerking moments. Voltage-gated calcium channel (VGCC) subunit α2δ-1 is the binding site for gabapentinoids used to treat epilepsy and neuropathic pain. However, this class of drugs showed severe side effects associated with CNS and respiratory depression. Hence, we screened a total of 2583 phytochemicals from the Comprehensive Marine Natural Products Database for their drug likeliness and pharmacokinetics (ADME/T) properties. The selected phytochemicals were docked with the VGCC α2δ-1 protein target and the marketed AED Pregabalin is used as standard. The docking results helped to select 45 docked compounds with better binding affinity, among which Acanthiline A showed the maximum binding affinity with the binding energy of -11.9 kcal/mol, thus reflecting its potential anti-epileptic activity.

Molecular docking analysis of marine phytochemicals with BACE-1.

Alzheimer's disease (AD), a debilitating neurodegenerative condition, is characterized by progressive cognitive decline brought about by the deposition of amyloid beta (Aß) plaques in the brain initiates downstream neuronal dysfunction and death in AD pathogenesis. The ß-secretase (BACE-1) enzyme plays a crucial role in generating Aß from amyloid precursor protein (APP). Hence, we report the virtual screening of marine phytochemicals as BACE-1 inhibitors. 2583 compounds, retrieved from Comprehensive Marine Natural Product Database (CMNPD), were primarily screened for drug-likeliness and blood-brain barrier permeability using admetSAR 2.0 and in-house BBBper tool and resulted in a total of 635 phytochemicals, selected for further docking studies using BACE-1 as target receptor and Atabecestat as standard BACE-1 inhibitor. Seven of 635 compounds docked against BACE-1, showed better binding affinities than Atabecestat, with the red algal metabolite lactodehydrothyrsiferol showing lowest binding energy of -10.83 kcal/mol. These compounds are worth investigating further to assess their neuroprotective efficacy and pharmacokinetic properties. The study also provides a rational framework to uncover novel pharmacophores from marine sources for AD therapy acting through BACE-1 inhibition.

Insights into amyloid precursor protein target through PPI network analysis.

Alzheimer's disease (AD) is the leading cause of dementia worldwide with therapeutic lacunae till date. The beta-amyloid (Aß) accumulation triggers AD pathogenesis, though clinical trials lowering Aß have not altered disease outcomes suggesting other interacting factors to be identified for drug design of AD. Therefore, it is of interest to identify potential hub proteins interlinked with disease-driving pathways using a network-based approach for AD therapeutic designing. Literature mining was done to identify proteins implicated in AD etiology. Protein-protein interactions (PPIs) were retrieved from the STRING database and merged into a single network using Cytoscape 3.10.1. The hub proteins involved in AD etiology were predicted based on the topological algorithms of CytoHubba. Six major proteins, with STRING database identifiers - APP, BACE1, PSEN1, MAPT, APOE4 and TREM2, were identified to be involved in AD pathogenesis. The merged network of PPIs of these proteins contained 51 nodes and 211 edges, as predicted by Analyzer module of Cytoscape. The Amyloid precursor protein (APP) emerged as the highest-scoring hub protein across multiple centrality measures and topological algorithms. Thus, current data provides evidence to support the ongoing investigation of APP's multifaceted functions and therapeutic potential for AD.

Clinical side-effects based drug repositioning for anti-epileptic activity.

Several generations of anti-epileptic drugs (AEDs) are available but have several associated side effects apart from a limited success rate. Drug repositioning strategies have gained importance in the last two decades owing to lower failure rates and economic burden. Drugs with similar side effect profiles may share a common mechanism of action and thus can be linked to other disease treatments. The present study was carried out to identify the newly approved drug candidate(s) as AEDs using clinical side-effects drug repositioning strategy. The clinical side effect similarity of drugs available in the SIDER v4.1 database was estimated against common side effects of 5 major marketed AEDs, using the 'dplyr' package library in the R. Further drugs were filtered based on Blood Brain Barrier permeability prediction and FDA-approval status. Molecular docking studies were performed for selected 26 hits (drugs) against previously identified epilepsy target receptors: Voltage-gated sodium channel α2 (Nav1.2), GABA receptor α1-ß1 (GABAr α1-ß1), and Voltage-gated calcium channel α-1 G (Cav3.1). Only 2 drugs (Ziprasidone and Paroxetine) showed better binding affinities against studied epilepsy receptors Nav1.2, GABAr α1-ß1, and Cav3.1, than their corresponding standard AEDs, i.e. Carbamazepine, Clonazepam, and Pregabalin, respectively. Ziprasidone reportedly showed seizure-like symptoms in ∼3% of patients and was hence omitted from further study. The MDS study of docked complexes of Paroxetine with selected epilepsy target receptors showed stable RMSD values and better interaction energies. The study reveals Paroxetine as a potential candidate to be repurposed for 1st line epileptic seizure medication.Communicated by Ramaswamy H. Sarma.

Drug repositioning for idiopathic epilepsy using gene expression signature data.

Epilepsy is one of the most common neurological disorders, affecting millions of patients with a substantial economic and human burden. About 30-40% of epileptic patients remain un-treated after the therapeutic option. Genetic or idiopathic epilepsy count about 40% of total epilepsy patients, showing a maximum percentage for drug-resistant epilepsy. Since the last century basic approach to understanding disease progression and drug discovery has been through the prism, exploring all possible causes and treatment options. Here we report about the gene expression-based drug repositioning study for epilepsy. Epilepsy gene expression data was retrieved from the Gene Expression Omnibus database, while drugs-associated gene expression data was retrieved from the Connectivity map (CMAP). The study predicted309 drug compounds which can alter genetic epilepsy-mediated gene signature using an in-house developed R-script. These compounds were docked against identified epilepsy targets- Voltage-gated sodium channel subunit α2 (Nav1.2); GABA receptor α1-ß1; and Voltage-gated calcium channel α1G (Cav3.1)using Carbamazepine, Clonazepam, and Pregabalin as standard drugs, respectively. Twenty-one predicted drug compounds showed better binding affinity than respective standards against the selected epileptic receptors. Among these drug compounds, Ergocalciferol, Oxaprozin, Flunarizine, Triprolidine and Cyproheptadine have been previously reported for anti-epileptic activities and can be potential hits to target idiopathic epilepsy.

Three-dimensional Quantitative Structure-activity Relationship (3DQSAR) and Molecular Docking Study of 2-((pyridin-3-yloxy)methyl) Piperazines as α7 Nicotinic Acetylcholine Receptor Modulators for the Treatment of Inflammatory Disorders.

BACKGROUND & OBJECTIVE: Comparative molecular field analysis (CoMFA) of 27 analogues of 2-((pyridin-3-yloxy)methyl)piperazine derivatives was carried out using software Tripos SYBYL X. Optimal r2 (0.854) and q2 (0.541) values were obtained for the developed 3D-QSAR model. The contour plots obtained from CoMFA analysis have shown 13.84% steric contribution and 66.14% electrostatic contribution towards an anti-inflammatory activity. METHODS: The homology model of the receptor protein, α7 nicotinic acetylcholine, was generated in SWISS MODELLER using auto template mode and was analysed for the quality using Procheck, QMEAN Z-score, Anolea and GROMOS plots. The QMEAN score for the model was observed to be - 3.862. The generated model of alpha 7 nicotinic acetylcholine receptor was used for docking study of 27 piperazine analogues using Auto-Dock 4.2.5.1. RESULTS: The dock score obtained from docking analysis was then correlated with experimental pIC50 values for in-silico validation of the developed CoMFA model and a good correlation was obtained with correlation coefficient (r2) value of -0.7378. CONCLUSION: The present investigation suggests an optimal 3D-QSAR with CoMFA model for further evaluating new chemical entities based on piperazine skeleton.

Insights into Molecular Interactions of human Wnt5b and Frizzled proteins for their role in teratogenicity.

Wnt-Fzd signalling plays vital role in different physiological pathways including embryonic development and supposed to be probable target of many teratogens. The present study was done to investigate the role of human Wnt5b interaction with different isoforms of human Fzds and also the molecular interactions of their complexes with selected known teratogens [Carbamazepine (CBZ), Retinoic acid (RA), Valproic acid (VPA), Aminopterin (AMP) and Phenytoin (PHY)] using Niclosamide (NLM) as standard. The models of hWnt5b and hFzd isoforms, whose solved crystal structures were unavailable, were generated using homology modeling and hWnt5b was subjected to protein-protein docking studies against different isoforms of hFzd. The macromolecular docking studies of hWnt5b-hFzds complexes revealed that hWnt5b had highest binding affinity with hFzd8 and lowest with hFzd1, respectively. The Cysteine rich domain (CRD) of hFzds docked against hWnt5b into a palm shaped opening or near the largest binding pocket as in hWnt5b-hFzd6. The possible role of Wnt-Fzd interactions in developmental toxicity due to selected teratogens were also investigated using molecular docking studies which showed that Retinoic Acid possessed the maximum binding affinity with binding energy of for hWnt5b-hFzd8 complex while VPA was observed to have lowest binding affinity towards all the studied hWnt5b-hFzd complexes.

Protein-Protein interaction network analyses of human WNT proteins involved in neural development.

WNT proteins are involved from initial of neural tissue specification to the end of cell fate determination and organ development. The present work was carried out to understand the involvement of different WNT isoforms (WNT3a, WNT5a and WNT7b) in neural development. A total of 718, 546 and 1004 PPIs for WNT3a, WNT5a and WNT7b respectively, were predicted by STRING database with confidence score more than 0.400. A network carrying all the selected PPIs of targeted proteins was constructed by using Cytoscape by assigning source node, target node and combined score as edge attribute. A total 2268 interactions of WNT3a, WNT5a and WNT7b were predicted to be involved in multiple signaling pathways and developmental processes. 43 of 2268 PPIs were refined after analyzing role of targeted proteins specifically in brain and neural development. WNT3a, WNT5a and WNT7a were predicted to be interacting with 18, 17 and 11 proteins, respectively, with average node degree score of 1.89, 2.12 and 1.82 respectively. The CytoHubba algorithm identified WNT3a, WNT5a, and WNT7b as hub proteins in neural development ranked on the basis of EPC (Edge Percolated Component) score of 9.352, 9.258 and 8.387.

Computational insights into promoter architecture of toxin-antitoxin systems of Mycobacterium tuberculosis.

Toxin-antitoxin (TA) systems are two component genetic modules widespread in many bacterial genomes, including Mycobacterium tuberculosis (Mtb). The TA systems play a significant role in biofilm formation, antibiotic tolerance and persistence of pathogen inside the host cells. Deciphering regulatory motifs of Mtb TA systems is the first essential step to understand their transcriptional regulation. In this study, in silico approaches, that is, the knowledge based motif discovery and de novo motif discovery were used to identify the regulatory motifs of 79 Mtb TA systems. The knowledge based motif discovery approach was used to design a Perl based bio-tool Mtb-sig-miner available at (https://github.com/zoozeal/Mtb-sig-miner), which could successfully detect sigma (σ) factor specific regulatory motifs in the promoter region of Mtb TA modules. The manual curation of Mtb-sig-miner output hits revealed that the majority of them possessed σB regulatory motif in their promoter region. On the other hand, de novo approach resulted in the identification of a novel conserved motif [(T/A)(G/T)NTA(G/C)(C/A)AT(C/A)] within the promoter region of 14 Mtb TA systems. The identified conserved motif was also validated for its activity as conserved core region of operator sequence of corresponding TA system by molecular docking studies. The strong binding of respective antitoxin/toxin with the identified novel conserved motif reflected the validation of identified motif as the core region of operator sequence of respective TA systems. These findings provide computational insight to understand the transcriptional regulation of Mtb TA systems.

Prediction of Delivery in Women with Threatening Preterm Labour using Phosphorylated Insulin-Like Growth Factor Binding Protein-1 and Cervical Length using Transvaginal Ultrasound.

INTRODUCTION: Preterm delivery remains a challenge in Obstetrics as it is responsible for significant cause of perinatal morbidity and mortality. At present there is no standard test for prediction of preterm labour for timely referral to a center with NICU facilities. AIM: To evaluate the effectiveness of the cervical phosphorylated insulin like growth factor binding protein-1(phIGFBP-1), cervical length measurement and combination of phIGFBP-1 with cervical length for Predicting Preterm Labour (PTL). MATERIALS AND METHODS: It was a observational prospective study done from January 2014 to April 2015 in Department of Obstetrics and Gynaecology, NDMC Medical College and Hindu Rao Hospital, Delhi, India. A total of 100 women with singleton pregnancy, between 24 and 36 weeks of gestation with complaint of uterine contractions were randomly selected. These women were subjected to detect phIGFBP-1 in cervical secretions and cervical length measurement by Transvaginal Sonography (TVS). Result of the test, cervical length and time lapse between test and delivery was noted and the results were analysed. The cervical length less than 25 mm was used as a cut off point for predicting pre-term delivery. Data was analysed using SPSS software version 20.0. RESULTS: The Negative Predictive Value (NPV) of phIGFBP-1 and cervical length was similar (95.2% vs 94.05%) respectively for prediction of preterm labour within one week of admission and 93.92% vs 94.80% at 37 weeks of gestational age. Combined test had higher NPV of 96.38% at 34 weeks of gestation and 94% within two days of admission. Positive Predictive Value (PPV) was low for both the test and combining the two-test did not have any advantage as far as PPV was concerned. Receiver Operating Characteristic (ROC) curve showed that the combined test had a superior result in predicting PTL compared to either phIGFBP-1 or cervical length. The combined test had steepest ROC curve at < 34 weeks of gestation (AUC-0.83 with 95% CI). CONCLUSION: The phIGFBP-1 test and cervical length have an almost equivalent ability to predict preterm delivery independently. The combined use of phIGFBP-1 and TVS for cervical length shows an increase in efficacy in predicting preterm labour.

Insights from the protein-protein interaction network analysis of Mycobacterium tuberculosis toxin-antitoxin systems.

Protein-protein interaction (PPI) network analysis is a powerful strategy to understand M. tuberculosis (Mtb) system level physiology in the identification of hub proteins. In the present study, the PPI network of 79 Mtb toxin-antitoxin (TA) systems comprising of 167 nodes and 234 edges was investigated. The topological properties of PPI network were examined by 'Network analyzer' a cytoscape plugin app and STRING database. The key enriched biological processes and the molecular functions of Mtb TA systems were analyzed by STRING. Manual curation of the PPI data identified four proteins (i.e. Rv2762c, VapB14, VapB42 and VapC42) to possess the highest number of interacting partners. The top 15% hub proteins were identified in the PPI network by employing two statistical measures, i.e. betweenness and radiality by employing cytohubba. Insights gained from the molecular protein models of VapC9 and VapC10 are also documented.

Synthesis, molecular docking and biological evaluation of some newer 2-substituted-4-(benzo[d][1,3]dioxol-5-yl)-6-phenylpyridazin-3(2H)-ones as potential anti-inflammatory and analgesic agents.

A new series of 2-substituted-4-(benzo[d][1,3]dioxol-5-yl)-6-phenylpyridazin-3(2H)-one derivatives has been synthesized and studied. The in vivo anti-inflammatory and analgesic activities of the synthesized compounds were evaluated using carrageen rat paw edema model and acetic acid induced writhing model, respectively. Side effect profile of the newly synthesized pyridazinones was assessed by gastric ulcerogenic and anti-platelet activity. The compounds were further evaluated for their inhibitory activity against cyclooxygenase enzyme (COX-1/COX-2) by in vitro colorimetric COX (ovine) inhibitor screening assay method. The p-flourophenylpiperazine substituted analogue 14 exhibited most potent anti-inflammatory and analgesic activities with lower ulcer index and extremely good selectivity towards COX-2 versus COX-1 enzyme with a selectivity index of 10. Molecular docking studies showed appreciable binding of new pyridazinone analogues with the amino acids present at the active site of hCOX-2 enzyme.

An Incidental Finding of Bilateral Dysgerminoma During Cesarean Section: Dilemmas in Management.

Dysgerminoma is an uncommon malignant tumour arising from germ cells of ovary. It occurs mostly in the reproductive age group. Its association with pregnancy is rare. Its management remains a challenge especially in an unsuspected case. We present a case of a woman, aged 28-year-old gravida2 para1 who reported to us at 36 weeks' pregnancy with severe preeclampsia and previous caesarean section. On ultrasound she was reported as having subserosal fibroids with single live fetus of 35 weeks and 3 days gestation. She delivered a live baby by caesarean section done for failed induction. Intraoperatively bilateral ovarian masses were found and removed which were later confirmed to be dysgerminoma on histopathological examination. As she was not diagnosed dysgerminoma pre-operatively, complete work up i.e., tumour markers and MRI was not done, leading to dilemmas in management. Though standard protocols for management of dysgerminoma with pregnancy exist, yet management of these incidentally diagnosed dysgerminomas remains a dilemma.

Acquired Clitoromegaly: A Gynaecological Problem or an Obstetric Complication?

Acquired non-hormonal clitoromegaly is a rare condition and is due to benign or malignant tumours and sometimes idiopathic. Few cases of clitoral abscesses have been reported after female circumcision. We hereby report a case of clitoral abscess causing acquired clitoromegaly following an obstetrical surgery.

Homology modelling and molecular docking studies of human placental cadherin protein for its role in teratogenic effects of anti-epileptic drugs.

Anti-epileptic drugs (AEDs) have high risk of teratogenic side effects, including neural tube defects while mother is on AEDs for her own prevention of convulsions during pregnancy. The present study investigated the interaction of major marketed AEDs and human placental (hp)-cadherin protein, in-silico, to establish the role of hp-cadherin protein in teratogenicity and also to evaluate the importance of Ca(2+) ion in functioning of the protein. A set of 21 major marketed AEDs were selected for the study and 3D-structure of hp-cadherin was constructed using homology modelling and energy minimized using MD simulations. Molecular docking studies were carried out using selected AEDs as ligand with hp-cadherin (free and bound Ca(2+) ion) to study the behavioural changes in hp-cadherin due to presence of Ca(2+) ion. The study reflected that four AEDs (Gabapentin, Pregabalin, Remacimide and Vigabatrine) had very high affinity towards hp-cadherin and thus the later may have prominent role in the teratogenic effects of these AEDs. From docking simulation analysis it was observed that Ca(2+) ion is required to make hp-cadherin energetically favourable and sterically functional.

QSAR analyses of organophosphates for insecticidal activity and its in-silico validation using molecular docking study.

The present work was carried out to design and develop novel QSAR models using 2D-QSAR and 3D-QSAR with CoMFA methodology for prediction of insecticidal activity of organophosphate (OP) molecules. The models were validated on an entirely different external dataset of in-house generated combinatorial library of OPs, by completely different computational approach of molecular docking against the target AChE protein of Musca domestica. The dock scores were observed to be in good correlation with 2D-QSAR and 3D-QSAR with CoMFA predicted activities and had the correlation coefficients (r(2)) of -0.62 and -0.63, respectively. The activities predicted by 2D-QSAR and 3D-QSAR with CoMFA were also observed to be highly correlated with r(2)=0.82. Also, the combinatorial library molecules were screened for toxicity in non-target organisms and degradability using USEPA-EPI Suite. The work was first step towards computer aided design and development of novel OP pesticide candidates with good insecticidal property but lower toxicity in non-targeted organisms and having biodegradation potential.

Molecular Dynamics of Rab7::REP1::GGTase-II Ternary Complex and Identification of Their Putative Drug Binding Sites.

The structure-function correlation of membrane proteins have been a difficult task, particularly in context to transient protein complexes. The molecular simulation of ternary complex of Rab7::REP1::GGTase-II was carried out to understand the basic structural events occurring during the prenylation event of Rab proteins, using the software YASARA. The study suggested that the C-terminus of Rab7 has to be in completely extended conformation during prenylation to reach the active site of RabGGTase-II. Also, attempt was made to find putative drug binding sites on the ternary complex of Rab7::REP1::GGTase-II using Q-SiteFinder programme. The comprehensive consensus probe generated by the program revealed a total of 10 major pockets as putative drug binding sites on Rab7::REP:: GGTase-II ternary complex. These pockets were found on REP protein and GGTase protein subunits. The Rab7 was found to be devoid of any putative drug binding sites in the ternary complex. The phylogenetic analysis of 60 Rab proteins of human was carried out using PHYLIP and study indicated the close phylogenetic relationship between Rab7 and Rab9 proteins of human and hence with further in silico study, the present observations can be extrapolated to Rab9 proteins. The study paves a good platform for further experimental verifications of the findings and other in silico studies like identifying the potential drug targets by searching the putative drug binding sites, generating pharmacophoric pattern, searching or constructing suitable ligand and docking studies.

Effectiveness of sal deoiled seed cake as an inducer for protease production from Aeromonas sp. S1 for its application in kitchen wastewater treatment.

The present study is an attempt to demonstrate the feasibility of sal (Shorea robusta) deoiled cake--a forest-based industrial by-product--as a cheaper media supplement for augmented protease production from Aeromonas sp. S1 and application of protease in the treatment of kitchen wastewater. Under optimized conditions, protease production could successfully be enhanced to 5.13-fold (527.5 U mL(-1)) on using sal deoiled seed cake extract (SDOCE), as medium additive, compared to an initial production of 102.7 U mL(-1) in its absence. The culture parameters for optimum production of protease were determined to be incubation time (48 h), pH (7.0), SDOCE concentration (3 % (v/v)), inoculum size (0.3-0.6 % (v/v)), and agitation rate (100 rpm). The enzyme was found to have an optimum pH and temperature of 8.0 and 60 °C, respectively. The protease preparation was tested for treatment of organic-laden kitchen wastewater. After 96 h of wastewater treatment under static condition, enzyme preparation was able to reduce 74 % biological oxygen demand, 37 % total suspended solids, and 41 % oil and grease. The higher and improved level of protease obtained using sal deoiled seed cake-based media hence offers a new approach for value addition to this underutilized biomass through industrial enzyme production. The protease produced using this biomass could also be used as pretreatment tool for remediation of organic-rich food wastewater.

Auto-immune hepatitis following delivery.

Auto-immune hepatitis first presenting in the early postpartum period is rare. Immunosuppressive effects of pregnancy result in delayed manifestation of auto-immune hepatitis, and in established cases, the spontaneous improvements are there. Auto-immune hepatitis should be considered in the differential diagnosis of liver dysfunction first presenting in the early postpartum period. A case of postpartum hepatitis of auto-immune aetiology is being presented here. It is disease of unknown aetiology, characterised by inflammation of liver (as evidenced by raised serum transaminases, presence of interface hepatitis on histological examination), hypergammaglobulinaemia (> 1.5 times normal), presence of auto-antibodies [(antinuclear antibodies (ANA)], smooth muscle antibody (SMA) and antibody to liver-kidney microsome type 1 (LKM1) in the absence of viral markers ie, hepatitis B (HBsAg) and C (AntiHCV) and excellent response to corticosteroid therapy.