Cross Blood Brain Barrier Research Articles

Raman spectroscopy for the detection of organ distribution and clearance of PEGylated reduced graphene oxide and biological consequences.

Graphene, a 2D carbon material has found vast application in biomedical field because of its exciting physico-chemical properties. The large planar sheet like structure helps graphene to act as an effective carrier of drug or biomolecules in enormous amount. However, limited data available on the biocompatibility of graphene upon interaction with the biological system prompts us to evaluate their toxicity in animal model. In this study organ distribution, clearance and toxicity of PEGylated reduced nanographene (PrGO) on Swiss Albino mice was investigated after intraperitoneal and intravenous administration. Biodistribution and blood clearance was monitored using confocal Raman mapping and indicated that PrGO was distributed on major organs such as brain, liver, kidney, spleen and bone marrow. Presence of PrGO in brain tissue suggests that it has the potential to cross blood brain barrier. Small amount of injected PrGO was found to excrete via urine. Repeated administration of PrGO induced acute liver injury, congestion in kidney and increased splenocytes proliferation in days following exposure. Hence the result of the study recommended that PrGO should undergo intensive safety assessment before clinical application or validated to be safe for medical use.

Neuropsychiatric morbidity in HIV/ AIDS

Human-immunodeficiency (HIV) virus is a neurotropic virus that enters the central nervous system by crossing blood brain barrier early in infection. HIV virus independently infects and destroys neuronal cells causing neuropsychiatric morbidity ranging from psychiatric illnesses to cognitive deficits. Several research studies have consistently reported higher prevalence of neuropsychiatric manifestations in patients with HIV/ AIDS. Further, there is an urgent need to sensitize health care providers regarding the relationship between HIV/ AIDS and neuropsychiatric morbidity to empower them to screen for psychiatric diseases.An early identification and treatment of psychiatric conditions in patients with HIV will help to improve compliance to anti-retroviral therapy, & coping with stress of living with HIV thereby improving quality of life. The review discusses prevalence of psychiatric morbidity in patients with HIV/ AIDS.

WITHDRAWN: CSN1201, , a subunit of the COP9 signalosome, regulates the virulence in Cryptococcus neoformans infection

The COP9 signalosome (CSN) is a multisubunit protein complex, and it now has been found to participate in diverse cellular and developmental processes in various eukaryotic organisms. Cryptococcus neoformans (C. neoformans) is an important basidiomycete pathogen that causes life-threatening meningoencephalitis primarily in the immune compromised population. Here, we generated CSN deletion mutants to investigate the role in Cryptococcus infection. Compared to other CSN mutants, we identified a CSN1201 mutant exhibited severely attenuated virulence. Deletion of CSN1201 made cryptococcal cells more susceptible to nearly all in vitro stresses. Furthermore, deletion of CSN1201 obviously impaired survival of C. neoformans. At the same time, in vivo virulence assay of mouse infection models demonstrated that CSN1201 significantly enhanced the virulence of C. neoformans compared with the other CSN subunit strains, while ELISA analysis of C. neoformans infection in innate or adaptive immune response showed that deletion of CSN1201 significantly impaired cytokines and interferon expression. In vitro model of the blood-brain barrier (BBB) analysis indicated that deletion of CSN1201 reduced the invasion efficacy of Cryptococcusto cross BBB. Taken together, our findings reveal a novel mechanism of CSN1201, which plays a critical role for the virulence composite of C. neoformans, and also provides an additional yeast survival and propagation advantage in the host.

In silico identification of promiscuous scaffolds as potential inhibitors of 1-deoxy-d-xylulose 5-phosphate reductoisomerase for treatment of Falciparum malaria

Context: Malaria remains one of the prevalent infectious diseases worldwide. Plasmodium falciparum 1-deoxy-d-xylulose-5-phosphate reductoisomerase (PfDXR) plays a role in isoprenoid biosynthesis in the malaria parasite, making this parasite enzyme an attractive target for antimalarial drug design. Fosmidomycin is a promising DXR inhibitor, which showed safety as well as efficacy against Plasmodium falciparum malaria in clinical trials. However, due to its poor oral bioavailability and non-drug-like properties, the focus of medicinal chemists is to develop inhibitors with improved pharmacological properties. Objective: This study described the computational design of new and potent inhibitors for deoxyxylulose 5-phosphate reductoisomerase and the prediction of their pharmacokinetic and pharmacodynamic properties. Material and methods: A complex-based pharmacophore model was generated from the complex X-ray crystallographic structure of PfDXR using MOE (Molecular Operating Environment). Furthermore, MOE-Dock was used as docking software to predict the binding modes of hits and target enzyme. Results: Finally, 14 compounds were selected as new and potent inhibitors of PfDXR on the basis of pharmacophore mapping, docking score, binding energy and binding interactions with the active site residues of the target protein. The predicted pharmacokinetic properties showed improved permeability by efficiently crossing blood–brain barrier. While, in silico promiscuity binding data revealed that these hits also have the ability to bind with other P. falciparum drug targets. Discussion and conclusion: In conclusion, innovative scaffolds with novel modes of action, improved efficacy and acceptable physiochemical/pharmacokinetic properties were computationally identified.

Delivery of Nanoparticles for Treatment of Brain Tumor

Malignant brain tumor is a highly challenging disease for diagnosis, treatment, and management. Cytotoxicity, distribution and the ability to cross blood brain barrier are some of the most significant issues for the chemotherapy of brain tumors. Nanotechnology has been widely exploited in drug delivery with great potential in improving the drug efficiency and efficacy. The advent of nanotechnology would greatly facilitate the early detection and treatment of brain tumors. This review will be primarily focused on current nano drug delivery system for brain cancer therapy. Meanwhile, the existing impediments for therapeutic nanomedicines and critical analysis of the different delivery nanoparticles are also discussed. We systematically evaluated the major factors that impact the current nanomedicines for brain tumor therapy. Meanwhile, various nanoparticle-based formulations for brain cancer detection and therapy are evaluated. 124 papers were included in this review. From the analysis of the nanomaterials, seven major nanomaterials have been discussed regarding the functionality and current therapeutic significance. The review also explains in detail about the different types of nanomaterials and their functionalities. This shows that each of these nanomaterials has specialized functions for the treatment of various kinds of brain cancer. Nanomaterials provide a viable potential diagnosis mechanis. In the future, more research needs to be focused on developing a better diagnosis tool for detection of cancer on an urgent basis. Blood-brain barrier and cytotoxicity are some of the primary root causes for the impediment of treatment of cancer using nanoparticles. Therefore, different delivery systems should be exploited for the nanoparticles to surmount these issues.

Abstract 1346: Magnetoelectric particles cross blood brain barrier to deliver anti-tumor peptide to glioblastoma cells with on-demand release

Abstract Background: Despite significant progress in targeted drug delivery, glioblastoma is one of the least treatable tumors today. Delivering therapy across the blood-brain barrier (BBB) and overcoming resistance of tumor cells to current treatments remains a formidable task. The objective of the current in vitro and in vivo study was to show how a new class of multifunctional nanoparticles termed magnetoelectric nanoparticles (MENs) are used to achieve high-efficacy delivery of a therapeutic load across BBB, then release the load on demand, without affecting normal cells, via application of a specially tailored command sequence of D.C. and A.C. magnetic fields. Methods: Growth hormone (GH)-releasing hormone (GHRH) antagonists, a class of anti-tumor peptides, block the release of tumorigenic insulin-like growth factors. Glioblastoma cell line U87 MG were treated with 1 μM of GHRH antagonist MIA-690 bound to GMO-MENs in MEM media supplemented with 5% FBS and 1% penstrep. In parallel, an in vitro BBB experiment, designed using transwells, applied a D.C. magnetic field gradient to determine optimal field and exposure time for MENs to penetrate the BBB. Next, experimental cells were placed on a D.C. magnetic field (100 Oe) for 12 h to induce nanoelectroporation, then an A.C. field (∼50 Hz) for 2 h to release the peptide intracellularly. Control cells were treated with MIA-690 peptide only, GMO-MENs only, and MIA-690 bound to GMO-MENs at varying magnetic fields and exposure times. Cells were incubated at 37°C with 5% CO2 in a humidified atmosphere. At 24 h and 48 h post-treatment, trypan-blue vital stain assessed cell growth inhibition. Cells were then washed and lysed to measure the concentration of MENs, and MIA-690 using ICP-MS and spectrophotometry, respectively. AFM and SEM-EDS imaged MENs in cell lysate and brain tissue from mice IV injected with MENs, to find signature peaks of Ba and Ti representing the outer core of MENs, to ascertain if particles cross the BBB in vivo. Summary of data: Glioblastoma cells treated with MIA-690 bound to GMO-MENs on a D.C. magnetic field for 12 h, then an A.C. field for 2 h exhibited the greatest penetration of MENs and inhibition of tumor growth. AFM and SEM-EDS imaging showed MENs in cell lysate treated with D.C. for 12 h, but not 2 h or with no magnetic field, confirming application of a low D.C. field for 12 h triggers MENs’ penetration. On-demand MIA-690 intracellular release was highest after exposure to 12 h of D.C. field, then A.C. field at 50 Hz. Confocal microscopy confirmed a transfer of at least 50% of drug-loaded MENs across in vitro BBB, requiring 200 Oe/cm for 5 h. SEM-EDS images of brain slices taken from mice treated with MENs confirmed the presence of Ba and Ti, indicating MENs are able to cross BBB in vivo. Conclusion: Functionalized MENs are effective in treating glioblastomas using targeted, on-demand release of anti-tumor drug with the ability to cross the BBB. Citation Format: Tiffanie Stewart, Emmanuel Stimphil, Rakesh Guduru, Alexandra Rodzinski, Ping Liang, Carolyn Runowicz, Ren-Zhi Cai, Luis Salgueiro, Andrew Schally, Sakhrat Khizroev. Magnetoelectric particles cross blood brain barrier to deliver anti-tumor peptide to glioblastoma cells with on-demand release. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1346.

Abstract 2915: Penfluridol suppresses glioblastoma tumor growth by inhibiting sonic hedgehog signaling

Abstract Glioblastoma (GBM) is the most common brain tumor with poor survival rate. The main obstacle in the treatment of glioblastoma patients is the presence of blood brain barrier, which restricts the movement of the drugs to reach the brain. Penfluridol (PF) is known to cross blood brain barrier and is a clinically approved drug for schizophrenia patients. It is demonstrated and established by us that penfluridol suppresses the growth of metastasized breast cancer cells in brain giving us the rationale to evaluate it against glioblastoma (Alok Ranjan, Parul Gupta and Sanjay Srivastava, Cancer Research 2015). Penfluridol significantly reduced the viability of U87-MG, T98G and U251 MG glioblastoma cells with an IC50 of 6μM, 5.5μM and 9μM respectively after 24 h of treatment and induced apoptosis as exhibited by FITC/Annexin assay and cleavage of caspase 3 as well as PARP. It has been shown that GLI1, a transcription factor belonging to sonic hedgehog signaling is overexpressed in GBM and responsible for tumor progression. Our results demonstrated that penfluridol treatment reduced the expression of GLI1 in U87MG, T98G and U251 MG cells in concentration-dependent manner. In addition, overexpression of MGMT, a DNA repair enzyme has been linked to temozolomide (TMZ) resistance in GBM therapy. Combination of PF and TMZ induced more apoptosis and reduced the expression of GLI1 and MGMT as compared to PF or TMZ treatment alone. Our results further demonstrated that oral administration of PF inhibited the growth of GBM tumors by 66% and 72% in subcutaneous and intracranial GBM tumor model respectively. Immunohistochemical analysis of tumor tissue and western blot analysis of tumor lysate indicated down regulation of GLI1, MGMT and increase in cleavage of caspase 3, confirming in vitro finding. Apoptosis induction effect of PF treatment in tumor tissues was further confirmed by Tunel staining. Taken together, these results indicate that overall GBM tumor growth suppression by penfluridol was associated with inhibition of Gli1 and induction of apoptosis Citation Format: Alok Ranjan, Sanjay K. Srivastava. Penfluridol suppresses glioblastoma tumor growth by inhibiting sonic hedgehog signaling. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2915.

L-THEANINE SPARES STRIATAL NEURONS FROM 3-NP–INDUCED STRIATAL NEUROTOXICITY: ROLE OF NITRIC OXIDE PATHWAY

L-theanine is unique amino acid which readily crosses blood brain barrier and posses neuroprotective potential against neurodegenerative disorders including Huntington Disease (HD). HD is characterized by selective loss of GABAergic medium spiny neurons. Therefore, the present study was intended to investigate the effect of L-theanine against 3-NP induced striatal toxicity. Rats were administered with 3-NP for 21 days. L-theanine was given once a day, 1 hour prior to 3-NP treatment for 21 days and L-NAME (NOS inhibitor) and L-arginine (NOS activator) were administered 1 hour prior to L-theanine treatment. Body weight, behavioral parameters (locomotor activity, grip strength, narrow beam walk) observation was done on 1st, 7th, 14th, and 21st day after 3-NP treatment. On 22nd day, animals were sacrificed and rat striatum was isolated for biochemical (mitochondrial complex- II, LPO, GSH and nitrite), pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and neurochemical analysis (GABA, Glutamate, DA, NE, 5-HT, DOPAC, HVA, 5-HIAA and Adenosine). 3-NP treatment significantly altered body weight, locomotor activity, motor coordination, mitochondrial complex-II activity, oxidative defence, pro-inflammatory mediators (TNF-α, IL-6 and IL-1β), and striatal neurotransmitters level i.e. GABA, glutamate, catecholamines, adenosine, inosine and hypoxanthine whereas L-theanine treatment (25 & 50 mg/kg/day, p.o.) significantly prevented these alterations. Concurrent treatment of L-NAME with L-theanine (25 mg/kg/day, p.o.) significantly enhanced protective effect of L-theanine (25 mg/kg/day, p.o.) whereas concurrent treatment of L-arginine with L-theanine (50 mg/kg/day, p.o.) significantly decreased the protective effect of L-theanine (50 mg/kg/day, p.o.). The neuroprotective potential of L-theanine involves inhibition of detrimental nitric oxide production and prevention of neurotransmitters alteration in striatum.

Nanosized Drug Delivery Systems for Direct Nose to Brain Targeting: A Review.

Drug targeting to brain has always been problematic due to Blood-Brain Barrier (BBB), which, does not allow most of the drugs to pass through it as they are hydrophilic and macromolecular drugs. So, in order to bypass the BBB, alternative modes of administration were searched and nasal to brain delivery route was tried by many workers. Such studies yielded patented nano-formulations with the ability to cross blood brain barrier. Nanoparticles being smaller in size and large surface area help in increasing the rate of drug permeation to the brain. In this review work, emphasis has been laid on discussion on various works done in the field of nasal delivery of drugs to brain over the last decade. The works that are discussed in this paper show better drug targeting of brain when given through nasal route as nanoparticles. Experiments performed in animal models have clearly exhibited that nano-sized formulations are able to facilitate the delivery of drugs to brain through nose in comparison to tantamount drug solutions. However, it is not yet confirmed whether the drug is freed from the formulation in the nasal cavity and then absorbed or the nanoparticles themselves are absorbed and then the drug is released in the CNS. Furthermore, the toxicity studies were not carried out extensively in suitably designed model, which should be considered before going for further studies and application.

Carbofuran Modulating Functions of Acetylcholinesterase from Rat BrainIn Vitro

Carbofuran, a potential environmental xenobiotic, has the ability to cross blood brain barrier and to adversely influence brain functions. In the present study, the impact of carbofuran on the biophysical and biochemical properties of rat brain AChE has been evaluatedin vitro. This enzyme was membrane-bound which could be solubilised using Triton-X100 (0.2%, v/v), a nonionic detergent, in the extraction buffer (50 mM phosphate, pH 7.4). The enzyme was highly stable up to one month when stored at-20°C and exhibited optimum activity at pH 7.4 and 37°C. AChE displayed a direct relationship between activity and varying substrate concentrations (acetylthiocholine iodide (ATI)) by following Michaelis-Menten curve. TheKmandVmaxvalues as computed from the Lineweaver-Burk double reciprocal plot of the data were found to be 0.07 mM and 0.066 µmole/mL/min, respectively. The enzyme exhibited IC50value for carbofuran equal to 6.0 nM. The steady-state kinetic studies to determine mode of action of carbofuran on rat brain AChE displayed it to be noncompetitive in nature withKivalue equal to 5 nm. These experiments suggested that rat brain AChE was very sensitive to carbofuran and this enzyme might serve as a significant biomarker of carbofuran induced neurotoxicity.

Synthesis and antimicrobial evaluation of 2-hydroxynaphthalene-1,4-dione and 4H-chromene conjugates

4H-Chromene and 1,4-naphthoquinone systems are generally considered to be medicinally privileged scaffolds. We have designed novel conjugates that incorporated both these scaffolds, as such conjugates exhibit unique biological properties reflecting those due to individual units and collective presence. In this work, we have achieved facile, efficient, and high yielding synthesis of 19 such conjugates from readily available 2-alkylamino-4-methylsulfanyl-3-nitro-4H-chromenes and 2-hydroxynaphthalene-1,4-dione. Highly polar nitroketene-O,N-acetal unit present in the conjugates is designed to prevent crossing blood brain barrier. We have conducted structure activity relationship (SAR) studies based on initial antimicrobial screening of a set of ten conjugates against three Gram positive bacteria [Bacillus Subtilis, Staphylococcus aureus (MSSA), Staphylococcus aureus (MRSA)], one Gram negative bacteria (Escherichia coli), and two fungi (Aspergillus niger, Candida albicans). The SAR studies revealed that the conjugates with halogens at C(6) and C(8) positions of the 4H-chromene ring having C(2)NMe group display impressive activity, almost equal to that of standard drugs. None of the conjugates, however, showed antimalarial activity, although they possess 2-hydroxy-1,4-naphthoquinone unit.

L-theanine, a Component of Green Tea Prevents 3-Nitropropionic Acid (3-NP)-Induced Striatal Toxicity by Modulating Nitric Oxide Pathway.

L-theanine is unique amino acid which readily crosses blood brain barrier and possesses neuroprotective potential against neurodegenerative disorders including Huntington disease (HD). HD is characterized by selective loss of GABAergic medium spiny neurons. 3-nitropropionic acid (3-NP) induces a spectrum of HD-like neuropathology in rat striatum and widely used as experimental tool to study HD. Therefore, the present study was intended to investigate the effect of L-theanine against 3-NP-induced striatal toxicity and to explore its possible mechanism. Rats were administered with 3-NP for 21days. L-theanine was given once a day, 1h prior to 3-NP treatment for 21days and L-NAME (10mg/kg, i.p.), NO inhibitor and L-arginine (50mg/kg; i.p.), NO precursor were administered 1h prior to L-theanine treatment. Body weight and behavioral observation were made on weekly basis. On the 22nd day, animals were sacrificed, and the striatum was isolated for biochemical (LPO, GSH, and nitrite), pro-inflammatory cytokines and neurochemical analysis. 3-NP treatment significantly altered body weight, locomotor activity, motor coordination, mitochondrial complex-II activity, oxidative defense, pro-inflammatory mediators, and striatal neurotransmitters level. L-theanine pre-treatment (25 and 50mg/kg/day, p.o.) significantly prevented these alterations. In addition, concurrent treatment of L-NAME with L-theanine (25mg/kg/day, p.o.) significantly enhanced protective effect of L-theanine (25mg/kg/day, p.o.) whereas concurrent treatment of L-arginine with L-theanine (50mg/kg/day, p.o.) significantly ameliorated the protective effect of L-theanine (50mg/kg/day, p.o.). The neuroprotective potential of L-theanine involves inhibition of detrimental nitric oxide production and prevention of neurotransmitters alteration in the striatum.

Donepezil loaded PLGA-b-PEG nanoparticles: their ability to induce destabilization of amyloid fibrils and to cross blood brain barrier in vitro.

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease. Cholinesterase inhibitors (ChEIs) are commonly used for symptomatic treatment of neural transmission improvement in AD. Donepezil is a reversible and non-competitive ChEI which is clinically used for palliative treatment of AD. The aim of the present study was to investigate the destabilizing effect of donepezil loaded poly(lactic-co-glycolic acid)-block-poly (ethylene glycol) [PLGA-b-PEG] nanoparticles on fibril formation in vitro and the ability of these nanoparticles to cross blood brain barrier (BBB) using in vitro BBB model and the neuroprotective effects of free donepezil and donepezil loaded PLGA-b-PEG nanoparticles. Donepezil loaded PLGA-b-PEG nanoparticles were prepared with double emulsion method. Destabilizing effect of these donepezil loaded particles on the amyloid-beta fibril (Aβ1-40 and Aβ1-42) formation was determined in vitro. Nanoparticles were found to have small particle size and have destabilizing effect on fibril formation. In vitro BBB model was successfully prepared. Nanoparticles showed the ability to cross the BBB and showed a controlled release profile in this system. IL-1β, IL-6, GM-CSF, TGF-β, MCP-1 and TNF-α levels were found to be increased in both gene and protein expression levels in astrocytes incubated with amyloid fibrils in in vitro BBB model suggesting an increased inflammation. Free donepezil and donepezil loaded nanoparticle administration caused a significant dose-dependent decrease in both gene and protein expression levels of IL-1β, IL-6, GM-CSF and TNF-α. No significant changes were observed for TGF-β and MCP-1.

Fluoxetine-induced toxicity results in human placental glutathione S-transferase-π (GST-π) dysfunction

Context: The antidepressant drug fluoxetine (FLU) is considered in the group of selective serotonine re-uptake inhibitors. Its distribution in brain and binding to human brain glutathione S-transferase-π (GST-π) have been shown. FLU can cross blood brain barrier and placenta, accumulate in fetus and may cause congenital malformations. Objective: To elucidate the interaction of placental GST-π with FLU. Materials and methods: First, concentration-dependent inhibition of human placental GST-π was evaluated by using different FLU concentrations and then 0.3125, 0.625, 1.25, 2.5 and 5 mM FLU concentrations were chosen and tested while keeping GSH concentration constant and 1-chloro-2,4-dinitrobenzene (CDNB) concentration varied and vice versa. The data were evaluated with different kinetic models and Statistica 9.00 for Windows. Results: The Vm, at variable [CDNB] (142 ± 16 U/mg protein) was 3 times higher than the Vm obtained at variable [GSH] (49 ± 4 U/mg protein). On the other hand, the Km for CDNB was ∼10 times higher than the Km for GSH (1.99 ± 0.36 mM versus 0.21 ± 0.06 mM). The IC50 value for FLU was 8.6 mM. Both at constant [CDNB] and variable [GSH] and at constant [GSH] and variable [CDNB] the inhibition types were competitive with the Ki values of 5.62 ± 4.37 and 8.09 ± 1.27 mM, respectively. Conclusion: Although the Ki values obtained for FLU in vitro are high, due to their uneven distribution, long elimination time and inhibitory behavior on detoxification systems, it may cause defects in adults but these effects may be much more severe in fetus and result in congenital malformations.

Polymers in Drug Delivery

Polymers are being used extensively in drug delivery due to their surface and bulk properties. They are being used in drug formulations and in drug delivery devices. These drug delivery devices may be in the form of implants for controlled drug delivery. Polymers used in colloidal drug carrier systems, consisting of small particles, show great advantage in drug delivery systems because of optimized drug loading and releasing property. Polymeric nano particulate systems are available in wide variety and have established chemistry. Non toxic, biodegradable and biocompatible polymers are available. Some nano particulate polymeric systems possess ability to cross blood brain barrier. They offer protection against chemical degradation. Smart polymers are responsive to atmospheric stimulus like change in temperature; pressure, pH etc. thus are extremely beneficial for targeted drug delivery. Some polymeric systems conjugated with antibodies/specific biomarkers help in detecting molecular targets specifically in cancers. Surface coating with thiolated PEG, Silica-PEG improves water solubility and photo stability. Surface modification of drug carriers e.g. attachment with PEG or dextran to the lipid bilayer increases their blood circulation time. Polymer drug conjugates such as Zoladex, Lupron Depot, On Caspar PEG intron are used in treatment of prostate cancer and lymphoblastic leukemia. Polymeric Drug Delivery systems are being utilized for controlled drug delivery assuring patient compliance.

A novel Nogo-66 receptor antagonist peptide promotes neurite regeneration in vitro.

The Nogo-66 receptor (NgR1), a receptor for Nogo-A, contributes to the inhibition of axonal regeneration in the adult central nervous system after traumatic injuries. Thus, NgR1 has been considered a critical target in axon regeneration therapy. Here, we identified a specific NgR1 antagonist peptide (HIYTALV, named NAP2) which promotes neurite regeneration in vitro from a phage display heptapeptide library. NAP2 was co-localized with NgR1 on the surface of PC12 cells and cerebellar granule cells (CGCs) by immunofluorescence assay. Horseradish peroxidase (HRP)-streptavidin-biotin assay further showed that NAP2 binds to NgR1 and the dissociation constant (Kd) was 0.45 μM Functional analyses indicated that NAP2 could reduce the inhibitory effects of Nogo-66 on neurite outgrowth in differentiated PC12 cells and CGCs by blocking the Nogo-66-induced activation of Rho-associated coiled coil-containing protein kinase (ROCK), collapsin response mediator protein 2 (CRMP2) and myosin light chain (MLC). Taken together, the small molecule NgR1 antagonist peptide NAP2 (MW: 815.98Da) has a potential ability in crossing blood brain barrier and will be a promising therapeutic agent for the treatment of spinal cord injury and neurodegenerative diseases.

Dietary curcumin: a potent natural polyphenol for neurodegenerative diseases therapy

Aggregation of misfolded amyloid proteins is a key factor for synaptic damage and impairment of neuronal communication in several neurodegenerative diseases. Since last few decayed several synthesized compounds, small molecules, drugs have been used to target against these misfolded proteins, but ultimately failed to prevent the misfolded protein aggregations and neurotoxicity effectively. Therefore, therapies for these diseases are elusive and under active investigation. As a potent anti-amyloid activity and its Pleotropic actions, recently curcumin has been used for treatment of several neurodegenerative diseases. It is the main ingredients of turmeric powder of the herb Curcuma longa. Its preferential binding properties with misfolded amyloid proteins attracted researchers to use as a potential therapy to prevent neurodegeneration. Importantly, curcumin is also a safe, inexpensive, easily available polyphenol and it can cross blood brain barrier. Therefore, it is considered one of the promising natural polyphenol for therapy of age related protein misfolding diseases, including several neurodegenerative disorders. In this mini review article we provided conceptual information about the multiple potentials of curcumin for prevention and/ or treatment of neurodegenerative diseases.

Rational design, synthesis and in vitro evaluation of allylidene hydrazinecarboximidamide derivatives as BACE-1 inhibitors.

BACE-1 (β-secretase) is considered to be one of the promising targets for treatment of Alzheimer's disease as it catalyzes the rate limiting step of Aβ-42 production. Herein, we report a novel class of allylidene hydrazinecarboximidamide derivatives as moderately potent BACE-1 inhibitors, having aminoguanidine substitution on allyl linker with two aromatic groups on either side. A library of derivatives was designed based on the docking studies, synthesized and evaluated for BACE-1 inhibition in vitro. The designed ligands displayed interactions with the catalytic aspartate dyad through guanidinium functionality. Further, the aromatic rings placed on either side of the linker occupied S1 and S3 active site regions contributing to the activity. These ligands were also predicted to follow Lipinski rule and cross blood brain barrier. Compound 2.21, having high docking score, was found to be most active with IC50 of 6.423μM indicating good correlation with docking prediction.

Salvaging brain ischemia by increasing neuroprotectant uptake via nanoagonist mediated blood brain barrier permeability enhancement

Ischemic stroke is a leading cause of adult disability and cognitive impairment worldwide. Neuroprotective therapy aims to save neurons by impeding the deleterious ischemic insults. However, the low efficiency of the neuroprotectants crossing blood brain barrier (BBB) prevents their clinical translation. In this work, a nanoagonist (NA) was developed to enhance neuroprotectant uptake by specifically increasing BBB permeability in brain ischemia. This NA first targeted ischemic brain vasculatures, temporarily opened local BBB by activating adenosine 2A receptors, and up-regulated the neuroprotectant uptake in brain ischemia. This NA significantly increased the delivery of superoxide dismutase (SOD), a free radical scavenger, into mouse brain ischemia. The combined treatment of NA/SOD achieved a five-fold ischemic volume reduction rate compared to the animal models treated with SOD alone. Non-invasive magnetic resonance imaging (MRI) confirmed the ischemia targeted BBB opening, increased brain drug delivery efficiency and up-regulated therapeutic response during the combined NA/SOD treatment. Since the inefficient brain drug delivery is a general problem for the treatment of central nervous system (CNS) diseases, this work provides a novel strategy to deliver therapeutics by crossing BBB with high efficiency and targeting specificity.

In silico Physicochemical Bioactivities and Toxicities Prediction of 3-chloro-6-arylpyridazines and 6-aryl- 4,5-dihydropyridazine-3(2H)-thiones having Antitubercular Activity

Purpose: In the present study, antitubercular activities and in silico physicochemical toxicities and bioactivity profile of some 3-chloro-6-arylpyridazines (3a-d) and 6-aryl-4,5-dihydropyridazine-3(2H)-thiones (4a-d) are studied. Approach: The compounds (3a-d) and (4a-d) were evaluated as antitubercular agents against Mycobacterium tuberculosis H37Rv by screening through in vitro Microplate Alamar Blue Assay (MABA) method. Findings: In silico physicochemical parameter revealed that the entire compounds follow Lipinski’s rule-of-5 to become a “drug like” molecule. ADME (absorption, distribution, metabolism and excretions) profile prediction has shown that all the compounds can be absorbed through human intestine (HIA + ), Caco-2 cell (Caco-2 + ) and can cross blood brain barrier (BBB + ), they all are non-substrate and non-inhibitor of p-glycoprotein. Compounds 4a-d are inhibitor of human microsomal enzyme like CYP 450 1A2, CYP 450 2C19 and CYP 450 3A4. Research limitations/implications: Compounds 4a-4d are better ligand for enzyme inhibition than 3a-d compounds. The MIC of compounds 4a-d and 3a is 6.25 µg/ml. They are potent than compound 3b-d with MIC 12.5 µg/ml. Originality: Toxicity prediction indicated that compounds 3a-3d and 4a-d are non-carcinogenic and non-mutagenic. Bioactivity prediction for compounds 3a-3d and 4a-d indicated better ligand as enzyme inhibitor in comparison to standard.