• Title/Summary/Keyword: Blood­brain barrier

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Characterization of Bacillus anthracis proteases through protein-protein interaction: an in silico study of anthrax pathogenicity

  • Banerjee, Amrita;Pal, Shilpee;Paul, Tanmay;Mondal, Keshab Chandra;Pati, Bikash Ranjan;Sen, Arnab;Mohapatra, Pradeep Kumar Das
    • CELLMED
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    • v.4 no.1
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    • pp.6.1-6.12
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    • 2014
  • Anthrax is the deadly disease for human being caused by Bacillus anthracis. Instantaneous research work on the mode of infection of the organism revealed that different proteases are involved in different steps of pathogenesis. Present study reports the in silico characterization and the detection of pathogenic proteases involved in anthrax infection through protein-protein interaction. A total of 13 acid, 9 neutral, and 1 alkaline protease of Bacillus anthracis were selected for analysing the physicochemical parameter, the protein superfamily and family search, multiple sequence alignment, phylogenetic tree construction, protein-protein interactions and motif finding. Among the 13 acid proteases, 10 were found as extracellular enzymes that interact with immune inhibitor A (InhA) and help the organism to cross the blood brain barrier during the process of infection. Multiple sequence alignment of above acid proteases revealed the position 368, 489, and 498-contained 100% conserved amino acids which could be used to deactivate the protease. Among the groups analyzed, only acid protease were found to interact with InhA, which indicated that metalloproteases of acid protease group have the capability to develop pathogenesis during B. anthracis infection. Deactivation of conserved amino acid position of germination protease can stop the sporulation and germination of B anthracis cell. The detailed interaction study of neutral and alkaline proteases could also be helpful to design the interaction network for the better understanding of anthrax disease.

Comparison of Mechanical Allodynia and Recovery of Locomotion and Bladder Function by Different Parameters of Low Thoracic Spinal Contusion Injury in Rats

  • Carter, Michael W.;Johnson, Kathia M.;Lee, Jun Yeon;Hulsebosch, Claire E.;Gwak, Young Seob
    • The Korean Journal of Pain
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    • v.29 no.2
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    • pp.86-95
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    • 2016
  • Background: The present study was designed to examine the functional recovery following spinal cord injury (SCI) by adjusting the parameters of impact force and dwell-time using the Infinite Horizon (IH) impactor device. Methods: Sprague-Dawley rats (225-240 g) were divided into eight injury groups based on force of injury (Kdyn) and dwell time (seconds), indicated as Force-Dwell time: 150-4, 150-3, 150-2, 150-1, 150-0, 200-0, 90-2 and sham controls, respectively. Results: After T10 SCI, higher injury force produced greater spinal cord displacement (P < 0.05) and showed a significant correlation (r = 0.813) between the displacement and the force (P < 0.05). In neuropathic pain-like behavior, the percent of paw withdrawals scores in the hindpaw for the 150-4, 150-3, 150-2, 150-1 and the 200-0 injury groups were significantly lowered compared with sham controls (P < 0.05). The recovery of locomotion had a significant within-subjects effect of time (P < 0.05) and the 150-0 group had increased recovery compared to other groups (P < 0.05). In addition, the 200-0 and the 90-2 recovered significantly better than all the 150 kdyn impact groups that included a dwell-time (P < 0.05). In recovery of spontaneous bladder function, the 150-4 injury group took significantly longer recovery time whereas the 150-0 and the 90-2 groups had the shortest recovery times. Conclusions: The present study demonstrates SCI parameters optimize development of mechanical allodynia and other pathological outcomes.

Study on Peripheral Mechanism and Opioid Receptors Implicated in Electroacupunture-induced Inbibition of Chronic Pain (만성통증을 억제하는 전침효과의 말초성 기전과 아편양물질수용기에 관한 연구)

  • 신홍기;이서은;박동석
    • The Journal of Korean Medicine
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    • v.24 no.3
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    • pp.108-117
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    • 2003
  • Objective : The central opioid mechanism of acupuncture analgesia has been fairly well documented in acute behavioral experiments, but little electrophysiological study has been performed on the peripheral mechanism and subtypes of opioid receptors responsible for acupuncture-induced antinociception in chronic animal models. In the present electrophysiological experiment, we studied the peripheral mechanism and opioid receptor subtypes which Were implicated in electroacupuncture-induced antinociception in the rat with chronic inflammatory and neurogenic pain. Methods : In the rat with complete Freund's adjuvant-induced inflammation and spinal nerve injury, dorsal horn cell responses to afferent C fiber stimulation were recorded before and after electroacupuncture (EA) stimulation applied to the contralateral Zusanli point for 30 minutes. Also studied Were the effects of specific opioid receptor antagonists and naloxone methiodide, which can not cross the blood-brain barrier, on EA-induced inhibitory action. Results : EA-induced inhibitory action was significantly attenuated by naloxone methiodide, suggesting that EA-induced inhibition was mediated through peripheral mechanism. Pretreatment, but not posttreatment of naltrexone and spinal application significantly blocked EA-induced inhibitory actions. In inflammatory and neurogenic pain models, ${\mu}-$ and ${\delta}-opioid$ receptor antagonists (${\beta}-funaltrexamine$ & naltrindole) significantly reduced EA-induced inhibitory action, but ${\kappa}-opioid$ receptor antagonist had weak inhibitory effect on EA-induced antinociception. Conclusion : These results suggest that 2Hz EA-stimulation induced antinoeiceptive action is mediated through peripheral as well as central mechanism, and mainly through ${\mu}-$ and ${\delta}-opioid$ receptors.

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Interaction of Nonsedating Antihistamines with Cerebral Muscarinic Receptors (비수기성 항 Histamine제와 대뇌 Muscarine 수용체와의 상호작용)

  • 김영열;이정수;박인숙
    • YAKHAK HOEJI
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    • v.43 no.5
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    • pp.642-651
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    • 1999
  • Nonsedating antihistamines do net cause sedation in therapeutic doses because these drugs hardly cross the blood-brain barrier. Since most of the peripheral side dffects of conventional antihistamines are related to their muscarinic receptor blocking action, the present study was performed to investigate whether nonsedating antihistamines interact with the muscarinic receptors and discriminate the muscarinic receptor subtypes in the rat cerebral microsomal fraction which containes both $M_1,{\;}M_2,{\;}M_3{\;}and{\;}M_4$ receptors. Five nonsedating antihistamines at high concentrations inhibited [$^3H$]QNB binding to the muscarinic receptor in a dose-dependent manner. The inhibition curves of these drugs except loratadine which showed positive cooperativity (nH=1.55) were steep (nH=1), indicating interaction with a single homogenous population of the binding sites. Astemizole, clemizole and mequitazine increased the $K_D$ value for [$^3H$]QNB without affecting the binding site concentrations, and this increase in the $K_D$ value resulted from the ability of these drugs to slow [$^3H$]QNB-receptor association. The Ki values of astemizole, clemizole and mequitazine for the inhibition for the inhibition of [$^3H$]QNB binding to muscarinic receptor were 0.58, 5.99 and $0.007{\;}{\mu}M$, respectively. However, loratadine and terfenadine inhibited noncompetitively [$^3H$]QNB binding with the normalized $IC_50$ value of about $2{\;}{\mu}M$. These results demonstrate that; 1) astemizole, clemizole and mequitazine interact directly with the muscarinic receptor at high concentrations; 2) muscarinic receptor blocking potency of these drugs varies widely among drugs; 3) these drugs do not discriminate between muscarinic receptor subtypes.

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Effects of α-lipoic acid on LPS-induced neuroinflammation and NLRP3 inflammasome activation through the regulation of BV-2 microglial cells activation

  • Kim, Su Min;Ha, Ji Sun;Han, A Reum;Cho, Sung-Woo;Yang, Seung-Ju
    • BMB Reports
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    • v.52 no.10
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    • pp.613-618
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    • 2019
  • Microglial cells are known as the main immune cells in the central nervous system, both regulating its immune response and maintaining its homeostasis. Furthermore, the antioxidant ${\alpha}-lipoic$ acid (LA) is a recognized therapeutic drug for diabetes because it can easily invade the blood-brain barrier. This study investigated the effect of ${\alpha}-LA$ on the inflammatory response in lipopolysaccharide (LPS)-treated BV-2 microglial cells. Our results revealed that ${\alpha}-LA$ significantly attenuated several inflammatory responses in BV-2 microglial cells, including pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and interleukin (IL)-6, and other cytotoxic molecules, such as nitric oxide and reactive oxygen species. In addition, ${\alpha}-LA$ inhibited the LPS-induced phosphorylation of ERK and p38 and its pharmacological properties were facilitated via the inhibition of the nuclear factor kappa B signaling pathway. Moreover, ${\alpha}-LA$ suppressed the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes, multiprotein complexes consisting of NLRP3 and caspase-1, which are involved in the innate immune response. Finally, ${\alpha}-LA$ decreased the genes accountable for the M1 phenotype, $IL-1{\beta}$ and ICAM1, whereas it increased the genes responsible for the M2 phenotype, MRC1 and ARG1. These findings suggest that ${\alpha}-LA$ alleviates the neuroinflammatory response by regulating microglial polarization.

Identification of G Protein Coupled Receptors Expressed in Fat Body of Plutella Xylostella in Different Temperature Conditions (온도 차이에 따른 배추좀나방 유충 지방체에서 발현되는 G 단백질 연관 수용체의 동정)

  • Kim, Kwang Ho;Lee, Dae-Weon
    • Korean Journal of Environmental Agriculture
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    • v.40 no.1
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    • pp.1-12
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    • 2021
  • BACKGROUND: G protein-coupled receptors (GPCRs) are widely distributed in various organisms. Insect GPCRs shown as in vertebrate GPCRs are membrane receptors that coordinate or involve in various physiological processes such as learning/memory, development, locomotion, circadian rhythm, reproduction, etc. This study aimed to identify GPCRs expressed in fat body and compare the expression pattern of GPCRs in different temperature conditions. METHODS AND RESULTS: To identify GPCRs genes and compare their expression in different temperature conditions, total RNAs of fat body in Plutella xylostella larva were extracted and the transcriptomes have been analyzed via next generation sequencing method. From the fat body transcriptomes, genes that belong to GPCR Family A, B, and F were identified such as opsin, gonadotropin-releasing hormone receptor, neuropeptide F (NPF) receptor, muthuselah (Mth), diuretic hormone receptor, frizzled, etc. Under low temperature, expressions of GPCRs such as C-C chemokine receptor (CCR), opsin, prolactin-releasing peptide receptor, substance K receptor, Mth-like receptor, diuretic hormone receptor, frizzled and stan were higher than those at 25℃. They are involved in immunity, feeding, movement, odorant recognition, diuresis, and development. In contrast to the control (25℃), at high temperature GPCRs including CCR, gonadotropin-releasing hormone receptor, moody, NPF receptor, neuropeptide B1 receptor, frizzled and stan revealed higher expression whose biological functions are related to immunity, blood-brain barrier formation, feeding, learning, and reproduction. CONCLUSION: Transcriptome of fat body can provide understanding the pools of GPCRs. Identifications of fat body GPCRs may contribute to develop new targets for the control of insect pests.

Enhancement Characteristics of Gadolinium Contrast Agent in the Rat Inner Ear Perilymph through CSF microcirculation (뇌척수액 미세순환을 통한 래트 내이 외림프의 가돌리늄 조영제 증강 특성)

  • Kim, Min Jung;Lee, Sang-Yeol;Lee, Hui Joong;Lee, Taekwan;Chang, Yongmin
    • Journal of Biomedical Engineering Research
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    • v.43 no.4
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    • pp.193-198
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    • 2022
  • Contrast enhanced magnetic resonance imaging using gadolinium-based contrast agent (GBCA) is a very useful in vivo technique to visualize the inner ear pathology including endolymphatic hydrops. Although systemic intravenous (IV) administration can visualize the perilymph space, the visualization was possible by indirect passage of contrast agent through blood-perilymph barrier. All animal experimental procedures were performed under anesthesia with 5% isoflurane. Lipopolysaccharide (LPS) was instilled into the left tympanic cavity through the tympanic membrane using a sterile 27gauge needle to induce hydrops model. Tucker-Davis Technologies system was used to measure Auditory Brainstem Responses (ABRs). For intracerebroven-tricular (ICV) administration, 25 µmol of GADOVIST (Bayer, Berlin, Germany) was used and diluted GADOVIST injection was 10 µl. MR imaging was acquired with a 9.4 Tesla MRI scanner. Transmit-receive volume coil with 40 mm inner diameter and 75 mm out diameter was used. ICV administration well demonstrated the strong enhancement along the cerebrospinal fluid (CSF) microcirculation pathway including CSF fluid in the subarachnoid space and CSF space of the inner ear structures. On the other hand, IV administration showed no contrast enhancement along the CSF microcirculation pathway and showed weak enhancement in the inner ear structures. In case of rat hydrops model, ICV administration showed that the reduced contrast enhancement in the perilymph space of the hydrops induced inner ear compared to the contrast enhancement in the perilymph space of the normal inner ear. New systemic ICV administration method provide contrast enhancement of GBCA in the inner ear through CSF microcirculation pathway.

The necessity of eliminating the interference of panaxatriol saponins to maximize the preventive effect of panaxadiol saponins against Parkinson's disease in rats

  • Yanwei Wang;Yufen Zhang;Yueyue Li;Zhizhen Zhang;Xiao-Yuan Lian
    • Journal of Ginseng Research
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    • v.48 no.5
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    • pp.464-473
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    • 2024
  • Background: The effects of individual panaxadiol saponin and panaxatriol saponin on rodent models of Parkinson's disease (PD) have been recognized. However, it is not clear whether purified total ginsenosides as an entirety has effect against PD in rat model. This study compared the protective effects of a purified panaxadiol saponin fraction (PDSF), a purified panaxatriol saponin fraction (PTSF), and their mixtures against the rotenone (ROT)-induced PD in rats. Methods: Potential effects of PDSF, PTSF, and their mixtures against motor dysfunction and impairments of nigrostriatal dopaminergic neurons (DN), blood-brain barrier (BBB), cerebrovascular endothelial cells (CEC), and glial cells were measured in the models of ROT-induced PD rats and cell damage. Pro-inflammatory NF-kB p65 (p65) activation was localized in DN and other cells in the striatum. Results: PDSF and PTSF had a dose-dependent effect against motor dysfunction with a larger effective dose range for PDSF. PDSF protected CEC, glial cells, and DN in models of PD rats and cell damage, while PTSF had no such protections. Chronic ROT exposure potently activated p65 in CEC with enhanced pro-inflammatory and decreased anti-inflammatory factors and impaired BBB in the striatum, PDSF almost completely blocked the ROT-induced p65 activation and maintained both anti- and pro-inflammatory factors at normal levels and BBB integrity, but PTSF aggravated the p65 activation with impaired BBB. Furthermore, PTSF nullified all the effects of PDSF when they were co-administrated. Conclusion: PDSF had significant protective effect against the ROT-induced PD in rats by protecting CEC, glial cells, and DN, likely through inhibiting NF-κB p65 in CEC from triggering neuroinflammation, and also directly protecting glial cells and neurons against ROT-induced toxicity. PDSF has great potential for preventing and treating PD.

Nanopharmaceutical Approach for Enhanced Anti-cancer Activity of Betulinic Acid in Lung-cancer Treatment via Activation of PARP: Interaction with DNA as a Target -Anti-cancer Potential of Nano-betulinic Acid in Lung Cancer-

  • Das, Jayeeta;Samadder, Asmita;Das, Sreemanti;Paul, Avijit;Khuda-Bukhsh, Anisur Rahman
    • Journal of Pharmacopuncture
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    • v.19 no.1
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    • pp.37-44
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    • 2016
  • Objectives: This study examined the relative efficacies of a derivative of betulinic acid (dBA) and its poly (lactide-co-glycolide) (PLGA) nano-encapsulated form in A549 lung cancer cells in vivo and in co-mutagen [sodium arsenite (SA) + benzo[a]pyrene (BaP)]-induced lung cancer in mice in vivo. Methods: dBA was loaded with PLGA nanoparticles by using the standard solvent displacement method. The sizes and morphologies of nano-dBA (NdBA) were determined by using transmission electron microscopy (TEM), and their intracellular localization was verified by using confocal microscopy. The binding and interaction of NdBA with calf thymus deoxyribonucleic acid (CT-DNA) as a target were analyzed by using conventional circular dichroism (CD) and melting temperature (Tm) profile data. Apoptotic signalling cascades in vitro and in vivo were studied by using an enzyme-linked immunosorbent assay (ELISA); the ability of NdBA to cross the blood-brain barrier (BBB) was also examined. The stage of cell cycle arrest was confirmed by using a fluorescence-activated cell-sorting (FACS) data analysis. Results: The average size of the nanoparticles was ~ 110 nm. Confocal microscopy images confirmed the presence of NdBA in the cellular cytoplasm. The bio-physical properties of dBA and NdBA ascertained from the CD and the Tm profiles revealed that NdBA had greater interaction with the target DNA than dBA did. Both dBA and NdBA arrested cell proliferation at G0/G1, NdBA showing the greater effect. NdBA also induced a greater degree of cytotoxicity in A549 cells, but it had an insignificant cytotoxic effect in normal L6 cells. The results of flow cytometric, cytogenetial and histopathological studies in mice revealed that NdBA caused less nuclear condensation and DNA damage than dBA did. TEM images showed the presence of NdBA in brain samples of NdBA fed mice, indicating its ability to cross the BBB. Conclusion: Thus, compared to dBA, NdBA appears to have greater chemoprotective potential against lung cancer.

A Novel Suberoylanilide Hydroxamic Acid Histone Deacetylase Inhibitor Derivative, N25, Exhibiting Improved Antitumor Activity in both Human U251 and H460 Cells

  • Zhang, Song;Huang, Wei-Bin;Wu, Li;Wang, Lai-You;Ye, Lian-Bao;Feng, Bing-Hong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4331-4338
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    • 2014
  • $N^1$-(2, 5-dimethoxyphenyl)-$N^8$-hydroxyoctanediamide (N25) is a novel SAHA cap derivative of HDACi, with a patent (No. CN 103159646). This invention is a hydroxamic acid compound with a structural formula of $RNHCO(CH_2)6CONHOH$ (wherein R=2, 5dimethoxyaniline), a pharmaceutically acceptable salt which is soluble. In the present study, we investigated the effects of N25 with regard to drug distribution and molecular docking, and anti-proliferation, apoptosis, cell cycling, and $LD_{50}$. First, we designed a molecular approach for modeling selected SAHA derivatives based on available structural information regarding human HDAC8 in complex with SAHA (PDB code 1T69). N25 was found to be stabilized by direct interaction with the HDAC8. Anti-proliferative activity was observed in human glioma U251, U87, T98G cells and human lung cancer H460, A549, H1299 cells at moderate concentrations ($0.5-30{\mu}M$). Compared with SAHA, N25 displayed an increased antitumor activity in U251 and H460 cells. We further analyzed cell death mechanisms activated by N25 in U251 and H460 cells. N25 significantly increased acetylation of Histone 3 and inhibited HDAC4. On RT-PCR analysis, N25 increased the mRNA levels of p21, however, decreased the levels of p53. These resulted in promotion of apoptosis, inducing G0/G1 arrest in U251 cells and G2/M arrest in H460 cells in a time-dependent and dose-dependent manner. In addition, N25 was able to distribute to brain tissue through the blood-brain barrier of mice ($LD_{50}$: 240.840mg/kg). In conclusion, our findings demonstrate that N25 will provide an invaluable tool to investigate the molecular mechanism with potential chemotherapeutic value in several malignancies, especially human glioma.