Displaying publications 41 - 60 of 95 in total

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  1. Asle-Rousta M, Oryan S, Ahmadiani A, Rahnema M
    EXCLI J, 2013;12:449-61.
    PMID: 26417237
    Sphingosine-1 phosphate (S1P) is involved in a variety of cellular processes via activation of S1P receptors (S1PRs; S1PR1 to S1PR5) that are highly expressed in the brain. It has been shown that the level of S1P is reduced in the brain of Alzheimer's disease (AD) patients. However, there is no study designed to evaluate the expression of S1PRs in AD brains. The objectives of the present work are (1) to examine the expression of S1PR1-3 in the hippocampus of beta amyloid (Aβ) 1-42 injected rats and (2) to clarify the effects of chronic S1PR1 activation on S1PR1-3 levels, spatial memory deficit and hippocampal damage in AD rats. SEW2871, the S1PR1 selective agonist, repeatedly was injected intraperitoneally during a period of two weeks. Upon Western Blot data bilateral intrahippocampal injection of Aβ1-42 decreased the expression of S1PR1 while increased S1PR2 level and did not affect that of S1PR3. We found that chronic administration of SEW2871 inhibited the reduction of S1PR1 expression and ameliorated spatial memory impairment in the Morris water maze task in rats. In addition, SEW2871 attenuated the Aβ1-42-induced hippocampal neuronal loss according to Nissl staining findings. Data in the current study highlights the importance of S1PR1 signaling pathway deregulation in AD development and suggests that activation of S1PR1 may represent a potential approach for developing new therapeutics to manage memory deficit and apoptosis associated with neurodegenerative disorders such as AD.
    Matched MeSH terms: Peptide Fragments
  2. Chan SL, Ong TC, Gao YF, Tiong YS, Wang de Y, Chew FT, et al.
    J Immunol, 2008 Aug 15;181(4):2586-96.
    PMID: 18684949
    A high incidence of sensitization to Blomia tropicalis, the predominant house dust mite species in tropical regions, is strongly associated with allergic diseases in Singapore, Malaysia, and Brazil. IgE binding to the group 5 allergen, Blo t 5, is found to be the most prevalent among all B. tropicalis allergens. The NMR structure of Blo t 5 determined represents a novel helical bundle structure consisting of three antiparallel alpha-helices. Based on the structure and sequence alignment with other known group 5 dust mite allergens, surface-exposed charged residues have been identified for site-directed mutagenesis and IgE binding assays. Four charged residues, Glu76, Asp81, Glu86, and Glu91 at around the turn region connecting helices alpha2 and alpha3 have been identified to be involved in the IgE binding. Using overlapping peptides, we have confirmed that these charged residues are located on a major putative linear IgE epitope of Blo t 5 from residues 76-91 comprising the sequence ELKRTDLNILERFNYE. Triple and quadruple mutants have been generated and found to exhibit significantly lower IgE binding and reduced responses in skin prick tests. The mutants induced similar PBMC proliferation as the wild-type protein but with reduced Th2:Th1 cytokines ratio. Mass screening on a quadruple mutant showed a 40% reduction in IgE binding in 35 of 42 sera of atopic individuals. Findings in this study further stressed the importance of surface-charged residues on IgE binding and have implications in the cross-reactivity and use of Blo t 5 mutants as a hypoallergen for immunotherapy.
    Matched MeSH terms: Peptide Fragments/immunology; Peptide Fragments/metabolism; Peptide Fragments/chemistry
  3. Tye SK, Razali NS, Ahmad Shauqi SA, Azeman NA, Basran NF, Liew JHJ, et al.
    Cardiol Young, 2024 Apr;34(4):900-905.
    PMID: 37965721 DOI: 10.1017/S1047951123003773
    OBJECTIVES: This study aimed to describe the perception of Malaysian patients with pulmonary hypertension towards palliative care and their receptivity towards palliative care.

    METHODS: This was a cross-sectional, single-centre study conducted via questionnaire. Patients aged 18 years old and above, who were diagnosed with non-curable pulmonary hypertension were recruited and given the assessment tool - perceptions of palliative care instrument electronically. The severity of pulmonary hypertension was measured using WHO class, N-terminal pro B-type natriuretic peptide and the 6-minute walking test distance.

    RESULTS: A total of 84 patients [mean age: 35 ±11 years, female: 83.3%, median N-terminal pro B-type natriuretic peptide: 491 pg/ml (interquartile range: 155,1317.8), median 6-minute walking test distance: 420m (interquartile range: 368.5, 480m)] completed the questionnaires. Patients with a higher WHO functional class and negative feelings (r = 0.333, p = 0.004), and cognitive reaction to palliative care: hopeless (r = 0.340, p = 0.003), supported (r = 0.258, p = 0.028), disrupted (r = 0.262, p = 0.025), and perception of burden (r = 0.239, p = 0.041) are more receptive to palliative care. WHO class, N-terminal pro B-type natriuretic peptide, and 6-minute walking test distance were not associated with higher readiness for palliative care. In logistic regression analyses, patients with positive feelings (β = 2.240, p = < 0.05), and practical needs (β = 1.346, p = < 0.05), were more receptive to palliative care.

    CONCLUSIONS: Disease severity did not directly influence patients' readiness for palliative care. Patients with a positive outlook were more receptive to palliative care.

    Matched MeSH terms: Peptide Fragments
  4. Kalra J, Kumar P, Majeed AB, Prakash A
    Pharmacol. Biochem. Behav., 2016 Jul-Aug;146-147:1-12.
    PMID: 27106205 DOI: 10.1016/j.pbb.2016.04.002
    Several lines of evidence indicate that beta amyloid (β-A) production, neurofibrillary tangles and neuroinflammation are interrelated in the pathogenesis of Alzheimer's disease (AD). AD is associated with enhanced β-A production and accumulation resulting in neuroinflammation probably via activation of lipoxygenase (LOX) and cyclooxygenase (COX) pathways. Therefore, the present study was designed to investigate the role of LOX and COX inhibitors (zafirlukast and valdecoxib) in amyloidogenesis in β-A1-42 oligomer induced experimental AD in rats. The behavioral activities were assessed using actophotometer, novel object recognition test (ORT), Morris water maze (MWM) followed by biochemical assessments, determination of proinflammatory cytokines and mediators (TNF-α, IL-1β and PGE2), β-A1-42 levels and histopathological analysis. ICV administration of β-A1-42 oligomer produced significant impairment in memory consolidation. In addition to this significant increase in mito-oxidative stress, neuroinflammatory markers, acetylcholinesterase (AChE) toxicity, β-A1-42 level, neuronal cell death and neuroinflammation are more profound in β-A1-42 oligomer treated AD rats. Administration of zafirlukast (15 and 30mg/kg), and valdecoxib (5 and 10mg/kg) significantly improved the behavioral performances and showed significant reversal of mito-oxidative damage declining the neuroinflammation in β-A1-42 oligomer treated rats. Furthermore, more profound effects were observed at the sub-therapeutic dose combination of zafirlukast (15mg/kg) and valdecoxib (5mg/kg). The results of the present study indicate that protective effects of zafirlukast and valdecoxib are achieved through the blockade of release of LOX and COX metabolites therefore, representing a new therapeutic target for treating AD and other neurodegenerative disorders.
    Matched MeSH terms: Peptide Fragments/administration & dosage; Peptide Fragments/metabolism; Peptide Fragments/toxicity*
  5. Boldbaatar D, Gunasekera S, El-Seedi HR, Göransson U
    J Nat Prod, 2015 Nov 25;78(11):2545-51.
    PMID: 26509914 DOI: 10.1021/acs.jnatprod.5b00463
    The Ricinus communis biomarker peptides RCB-1 to -3 comprise homologous sequences of 19 (RCB-1) or 18 (RCB-2 and -3) amino acid residues. They all include four cysteine moieties, which form two disulfide bonds. However, neither the 3D structure nor the biological activity of any of these peptides is known. The synthesis of RCB-1, using microwave-assisted, Fmoc-based solid-phase peptide synthesis, and a method for its oxidative folding are reported. The tertiary structure of RCB-1, subsequently established using solution-state NMR, reveals a twisted loop fold with antiparallel β-sheets reinforced by the two disulfide bonds. Moreover, RCB-1 was tested for antibacterial, antifungal, and cytotoxic activity, as well as in a serum stability assay, in which it proved to be remarkably stable.
    Matched MeSH terms: Peptide Fragments/isolation & purification*; Peptide Fragments/pharmacology; Peptide Fragments/chemistry
  6. Duceppe E, Patel A, Chan MTV, Berwanger O, Ackland G, Kavsak PA, et al.
    Ann Intern Med, 2020 01 21;172(2):96-104.
    PMID: 31869834 DOI: 10.7326/M19-2501
    Background: Preliminary data suggest that preoperative N-terminal pro-B-type natriuretic peptide (NT-proBNP) may improve risk prediction in patients undergoing noncardiac surgery.

    Objective: To determine whether preoperative NT-proBNP has additional predictive value beyond a clinical risk score for the composite of vascular death and myocardial injury after noncardiac surgery (MINS) within 30 days after surgery.

    Design: Prospective cohort study.

    Setting: 16 hospitals in 9 countries.

    Patients: 10 402 patients aged 45 years or older having inpatient noncardiac surgery.

    Measurements: All patients had NT-proBNP levels measured before surgery and troponin T levels measured daily for up to 3 days after surgery.

    Results: In multivariable analyses, compared with preoperative NT-proBNP values less than 100 pg/mL (the reference group), those of 100 to less than 200 pg/mL, 200 to less than 1500 pg/mL, and 1500 pg/mL or greater were associated with adjusted hazard ratios of 2.27 (95% CI, 1.90 to 2.70), 3.63 (CI, 3.13 to 4.21), and 5.82 (CI, 4.81 to 7.05) and corresponding incidences of the primary outcome of 12.3% (226 of 1843), 20.8% (542 of 2608), and 37.5% (223 of 595), respectively. Adding NT-proBNP thresholds to clinical stratification (that is, the Revised Cardiac Risk Index [RCRI]) resulted in a net absolute reclassification improvement of 258 per 1000 patients. Preoperative NT-proBNP values were also statistically significantly associated with 30-day all-cause mortality (less than 100 pg/mL [incidence, 0.3%], 100 to less than 200 pg/mL [incidence, 0.7%], 200 to less than 1500 pg/mL [incidence, 1.4%], and 1500 pg/mL or greater [incidence, 4.0%]).

    Limitation: External validation of the identified NT-proBNP thresholds in other cohorts would reinforce our findings.

    Conclusion: Preoperative NT-proBNP is strongly associated with vascular death and MINS within 30 days after noncardiac surgery and improves cardiac risk prediction in addition to the RCRI.

    Primary Funding Source: Canadian Institutes of Health Research.

    Matched MeSH terms: Peptide Fragments/blood*
  7. Brown TM, Robbins KE, Sinniah M, Saraswathy TS, Lee V, Hooi LS, et al.
    AIDS Res Hum Retroviruses, 1996 Nov 20;12(17):1655-7.
    PMID: 8947304
    Matched MeSH terms: Peptide Fragments/genetics*
  8. Ponnudurai G, Chung MC, Tan NH
    Arch Biochem Biophys, 1994 Sep;313(2):373-8.
    PMID: 8080286
    The L-amino acid oxidase of Malayan pit viper (Calloselasma rhodostoma) venom was purified to electrophoretic homogeneity. The molecular weight of the enzyme was 132,000 as determined by Sephadex G-200 gel filtration chromatography and 66,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It is a glycoprotein, has an isoelectric point of 4.4, and contains 2 mol of flavin mononucleotide per mole of enzyme. The N-terminal amino acid sequence of the enzyme was A-D-D-R-N-P-L-A-E-E-F-Q-E-N-N-Y-E-E-F-L. Kinetic studies suggest the presence of a alkyl side-chain binding site in the enzyme and that the binding site comprises at least four hydrophobic subsites. The characteristics of the binding site differ slightly from those of cobra venom L-amino acid oxidases.
    Matched MeSH terms: Peptide Fragments/chemistry
  9. Weiland F, Arentz G, Klingler-Hoffmann M, McCarthy P, Lokman NA, Kaur G, et al.
    J Proteome Res, 2016 11 04;15(11):4073-4081.
    PMID: 27569743
    Although acetylation is regarded as a common protein modification, a detailed proteome-wide profile of this post-translational modification may reveal important biological insight regarding differential acetylation of individual proteins. Here we optimized a novel peptide IEF fractionation method for use prior to LC-MS/MS analysis to obtain a more in depth coverage of N-terminally acetylated proteins from complex samples. Application of the method to the analysis of the serous ovarian cancer cell line OVCAR-5 identified 344 N-terminally acetylated proteins, 12 of which are previously unreported. The protein peptidyl-prolyl cis-trans isomerase A (PPIA) was detected in both the N-terminally acetylated and unmodified forms and was further analyzed by data-independent acquisition in carboplatin-responsive parental OVCAR-5 cells and carboplatin-resistant OVCAR-5 cells. This revealed a higher ratio of unacetylated to acetylated N-terminal PPIA in the parental compared with the carboplatin-resistant OVCAR-5 cells and a 4.1-fold increase in PPIA abundance overall in the parental cells relative to carboplatin-resistant OVCAR-5 cells (P = 0.015). In summary, the novel IEF peptide fractionation method presented here is robust, reproducible, and can be applied to the profiling of N-terminally acetylated proteins. All mass spectrometry data is available as a ProteomeXchange repository (PXD003547).
    Matched MeSH terms: Peptide Fragments/analysis*
  10. Kamariah K, Satgunasingam N, Nasri NM, Ng KY
    Med J Malaysia, 1993 Mar;48(1):40-5.
    PMID: 7688063
    Eighty-nine patients who had hydatidiform moles evacuated at the General Hospital, Kuala Lumpur, were followed with serum beta hCG determinations from October 1988 to June 1991. A regression curve for serum beta hCG, as measured by RIA, was derived from the results of 47 of the patients who demonstrated spontaneous regression of serum beta hCG titres. All 47 patients had normal serum titres at 135 days after evacuation. The mean time taken to reach normal level was 82.6 days, while the range was 39 to 135 days (5 to 19 weeks).
    Matched MeSH terms: Peptide Fragments/blood*
  11. Luan Eng LI, Wiltshire BG, Lehmann H
    Biochim. Biophys. Acta, 1973 Oct 18;322(2):224-30.
    PMID: 4765089
    Matched MeSH terms: Peptide Fragments/analysis
  12. Ismail N, Akhtar MN, Ismail M, Zareen S, Shah SA, Lajis NH, et al.
    Nat Prod Res, 2015;29(16):1571-4.
    PMID: 25471591 DOI: 10.1080/14786419.2014.985676
    The stem bark extracts of Knema laurina inhibited the hydrogen peroxide (H2O2)- and aggregated amyloid β-peptide 1-42 length (Aβ(1-42))-induced cell death in differentiated SH-SY5Y cells. Exposure of 250 μM H2O2 or 20 μM Aβ(1-42) to the cells for 24 h reduced 50% of cell viability. Pretreatment of cells with ethyl acetate extract (EAE) or n-butanol extract (BE) at 300 μg/mL and then exposure to H2O2 protected the cells against the neurotoxic effects of H2O2. Besides, methanolic extract (ME) at 1 and 10 μg/mL exerted neuroprotective effect on Aβ(1-42)-induced toxicity to the cells. These results showed that EAE, BE and ME exhibited neuroprotective activities against H2O2- and Aβ(1-42)-induced cell death. Flavonoids (3-6) and β-sitosterol glucoside (8) were isolated from the EAE. Compound 1 was isolated from hexane extract, and compounds 2 and 7 were isolated from dichloromethane extract. All these observations provide the possible evidence for contribution in the neuroprotective effects.
    Matched MeSH terms: Peptide Fragments/adverse effects
  13. Tan JW, Kim MK
    Molecules, 2016 Apr 25;21(5).
    PMID: 27120593 DOI: 10.3390/molecules21050548
    Alzheimer's disease is considered one of the major neurodegenerative diseases and is characterized by the production of β-amyloid (Aβ) proteins and progressive loss of neurons. Biochanin A, a phytoestrogen compound found mainly in Trifolium pratense, was used in the present study as a potential alternative to estrogen replacement therapy via the investigation of its neuroprotective effects against Aβ25-35-induced toxicity, as well as of its potential mechanisms of action in PC12 cells. Exposure of these cells to the Aβ25-35 protein significantly increased cell viability loss and apoptosis. However, the effects induced by Aβ25-35 were markedly reversed in the present of biochanin A. Pretreatment with biochanin A attenuated the cytotoxic effect of the Aβ25-35 protein by decreasing viability loss, LDH release, and caspase activity in cells. Moreover, we found that expression of cytochrome c and Puma were reduced, alongside with the restoration of Bcl-2/Bax and Bcl-xL/Bax ratio in the presence of biochanin A, which led to a decrease in the apoptotic rate. These data demonstrate that mitochondria are involved in the protective effect of biochanin A against Aβ25-35 and that this drug attenuated Aβ25-35-induced PC12 cell injury and apoptosis by preventing mitochondrial dysfunction. Thus, biochanin A might raise a possibility as a potential therapeutic agent for Alzheimer's disease and other related neurodegenerative diseases.
    Matched MeSH terms: Peptide Fragments/toxicity*
  14. Ladwig KH, Marten-Mittag B, Olliges E, Johar H, Atasoy S, Holdenrieder S, et al.
    J Affect Disord, 2025 Jan 15;369:174-181.
    PMID: 39321975 DOI: 10.1016/j.jad.2024.09.146
    BACKGROUND: Leptin, an adipokine suspected to play a role in coronary artery disease (CAD), may also be associated with deteriorated mental health. We investigated the prospective impact of recurrent depressed mood (RDM) on heightened plasma leptin levels in CAD patients.

    METHODS: Derived from the randomized SPIRR-CAD trial, plasma leptin were measured by the Human Leptin DuoSet ELISA at baseline in 539 patients (including 115 (21.3 %) women and 424 (78.7 %) men) and in 373 participants after 18-months follow up (T3). RDM was based on the clinical course from baseline to follow-up assessed by the Hamilton Depression Rating Scale (HAMD). Multivariate binary logistic regression models identified predictors for heightened leptin at T3.

    RESULTS: At baseline, highest leptin level (3rd tertile) was associated with type 2 diabetes (p = 0.009), heart failure symptoms (NYHA III) (p 

    Matched MeSH terms: Peptide Fragments/blood
  15. Thangeswaran D, Shamsuddin S, Balakrishnan V
    Mol Biol Rep, 2025 Aug 19;52(1):835.
    PMID: 40828210 DOI: 10.1007/s11033-025-10930-4
    BACKGROUND: Familial Alzheimer's disease (fAD) is a hereditary disease that develops at an unusually early age. The deposition of toxic amyloid-beta (Aβ) is a hallmark of fAD. Despite their genetic origin and increasing prevalence, no effective drugs currently exist. THICAPA, a novel compound containing a tetrahydroisoquinoline group of amines, is naturally found in the brain and food and has diverse medicinal properties. However, its potential role in modulating amyloidogenesis in patients with fAD has not yet been explored.

    METHODS AND RESULTS: We investigated the effects of THICAPA on the amyloid precursor protein (APP) processing pathway in fibroblasts derived from patients with fAD. The in vitro cytotoxicity assay revealed no significant THICAPA cytotoxicity in fAD (AG06840) or healthy fibroblast cell lines (GM05879). Aβ scavenging assay revealed that 50 µM THICAPA potentially scavenged aged Aβ42 oligomers in the healthy fibroblast line. Gene and protein expression analyses revealed reduced APP expression and mature/immature APP expression ratio, BACE1 and presenilin 1 downregulation, and ADAM10 upregulation. Protein quantification revealed a significant reduction in C-terminal fragment beta, soluble APP (sAPP)β, and Aβ42/40 ratio in the amyloidogenic pathway and elevated sAPPα in the non-amyloidogenic pathway. Moreover, reactive oxygen species detection indicated that THICAPA reduced ROS production in fibroblasts from patients with fAD by 41.63%, although its intrinsic antioxidant properties were modest.

    CONCLUSIONS: THICAPA attenuates amyloidogenesis and upregulates the non-amyloidogenic pathway while alleviating ROS production. These findings suggest that THICAPA is a potential therapeutic candidate for treating fAD.

    Matched MeSH terms: Peptide Fragments/metabolism
  16. Alawieyah Syed Mortadza S, Sim JA, Neubrand VE, Jiang LH
    Glia, 2018 03;66(3):562-575.
    PMID: 29143372 DOI: 10.1002/glia.23265
    Amyloid β (Aβ)-induced neuroinflammation plays an important part in Alzheimer's disease (AD). Emerging evidence supports a role for the transient receptor potential melastatin-related 2 (TRPM2) channel in Aβ-induced neuroinflammation, but how Aβ induces TRPM2 channel activation and this relates to neuroinflammation remained poorly understood. We investigated the mechanisms by which Aβ42 activates the TRPM2 channel in microglial cells and the relationships to microglial activation and generation of tumor necrosis factor-α (TNF-α), a key cytokine implicated in AD. Exposure to 10-300 nM Aβ42 induced concentration-dependent microglial activation and generation of TNF-α that were ablated by genetically deleting (TRPM2 knockout ;TRPM2-KO) or pharmacologically inhibiting the TRPM2 channel, revealing a critical role of this channel in Aβ42 -induced microglial activation and generation of TNF-α. Mechanistically, Aβ42 activated the TRPM2 channel via stimulating generation of reactive oxygen species (ROS) and activation of poly(ADPR) polymerase-1 (PARP-1). Aβ42 -induced generation of ROS and activation of PARP-1 and TRPM2 channel were suppressed by inhibiting protein kinase C (PKC) and NADPH oxidases (NOX). Aβ42 -induced activation of PARP-1 and TRPM2 channel was also reduced by inhibiting PYK2 and MEK/ERK. Aβ42 -induced activation of PARP-1 was attenuated by TRPM2-KO and moreover, the remaining PARP-1 activity was eliminated by inhibiting PKC and NOX, but not PYK2 and MEK/ERK. Collectively, our results suggest that PKC/NOX-mediated generation of ROS and subsequent activation of PARP-1 play a role in Aβ42 -induced TRPM2 channel activation and TRPM2-dependent activation of the PYK2/MEK/ERK signalling pathway acts as a positive feedback to further facilitate activation of PARP-1 and TRPM2 channel. These findings provide novel insights into the mechanisms underlying Aβ-induced AD-related neuroinflammation.
    Matched MeSH terms: Peptide Fragments/administration & dosage; Peptide Fragments/metabolism*
  17. Mohana-Kumaran N, Hill DS, Allen JD, Haass NK
    Pigment Cell Melanoma Res, 2014 Jul;27(4):525-39.
    PMID: 24655414 DOI: 10.1111/pcmr.12242
    Melanoma drug resistance is often attributed to abrogation of the intrinsic apoptosis pathway. Targeting regulators of apoptosis is thus considered a promising approach to sensitizing melanomas to treatment. The development of small-molecule inhibitors that mimic natural antagonists of either antiapoptotic members of the BCL-2 family or the inhibitor of apoptosis proteins (IAPs), known as BH3- or SMAC-mimetics, respectively, are helping us to understand the mechanisms behind apoptotic resistance. Studies using BH3-mimetics indicate that the antiapoptotic BCL-2 protein MCL-1 and its antagonist NOXA are particularly important regulators of BCL-2 family signaling, while SMAC-mimetic studies show that both XIAP and the cIAPs must be targeted to effectively induce apoptosis of cancer cells. Although most solid tumors, including melanoma, are insensitive to these mimetic drugs as single agents, combinations with other therapeutics have yielded promising results, and tests combining them with BRAF-inhibitors, which have already revolutionized melanoma treatment, are a clear priority.
    Matched MeSH terms: Peptide Fragments/therapeutic use*; Peptide Fragments/chemistry
  18. Mohamud R, Azlan M, Yero D, Alvarez N, Sarmiento ME, Acosta A, et al.
    BMC Immunol, 2013;14 Suppl 1:S5.
    PMID: 23458635 DOI: 10.1186/1471-2172-14-S1-S5
    Recombinant Mycobacterium bovis bacille Calmette-Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused to B cell epitopes from ESAT-6, CFP-10 and MTP40 proteins (rBCG032) were used to immunize Balb/c mice. Total IgG responses were determined against Mtb8.4 antigen and ESAT-6 and CFP-10 B cell epitopes after immunization with rBCG032. Mice immunized with rBCG032 showed a significant increase in IgG1 and IgG2a antibodies against ESAT-6 and MTP40 (P1) B cell epitopes and IgG3 against both P1 and P2 B cell epitopes of MPT40. Splenocytes from mice immunized with rBCG018 proliferated against Ag85B P2 and P3 T cell epitopes and Mtb8.4 protein whereas those from mice-immunized with rBCG032 responded against all Ag85B epitopes and the ESAT-6 B cell epitope. CD4⁺ and CD8⁺ lymphocytes from mice immunized with rBCG018 produced primarily Th1 type cytokines in response to the T cell epitopes. Similar pattern of recognition against the T cell epitopes were obtained with rBCG032 with the additional recognition of ESAT-6, CFP-10 and one of the MTP40 B cell epitopes with the same pattern of cytokines. This study demonstrates that rBCG constructs expressing either T or T and B cell epitopes of MTB induced appropriate immunogenicity against MTB.
    Matched MeSH terms: Peptide Fragments/immunology; Peptide Fragments/metabolism
  19. Ngeow WC, Atkins S, Morgan CR, Metcalfe AD, Boissonade FM, Loescher AR, et al.
    Neuroscience, 2011 May 5;181:271-7.
    PMID: 21377512 DOI: 10.1016/j.neuroscience.2011.02.054
    We have investigated the effect of three potential scar-reducing agents applied at a sciatic nerve repair site in C57-black-6 mice. Under anaesthesia the nerve was transected, repaired using four epineurial sutures, and 100 μl of either triamcinolone acetonide (1 mg/100 μl), an interleukin-10 peptide fragment (125 ng/100 μl or 500 ng/100 μl) or mannose-6-phosphate (M6P, 200 mM or 600 mM) was injected into and around the nerve. After 6 weeks the extent of regeneration was assessed electrophysiologically by determining the ratio of the compound action potential (CAP) modulus evoked by electrical stimulation of the nerve 2 mm distal or proximal to the repair site. The conduction velocity of the fastest components in the CAP was also calculated. The percentage area of collagen staining (PAS) at the repair site was analysed using Picrosirius Red and image analysis. Comparisons were made with a placebo group (100 μl of phosphate buffered saline) and sham-operated controls. The median CAP modulus ratio in the 600 mM M6P group was 0.44, which was significantly higher than in the placebo group (0.24, P=0.012: Kruskal-Wallis test). Conduction velocities were also faster in the 600 mM M6P group (median 30 m s(-1)) than in the placebo group (median 27.8 m s(-1); P=0.0197: Kruskal-Wallis test). None of the other treated groups were significantly different from the placebo, and all had significantly lower CAP ratios than the sham controls (P<0.05). All repair groups had a significantly higher PAS for collagen than sham controls. We conclude that the administration of 600 mM mannose-6-phosphate to a nerve repair site enhances axonal regeneration.
    Matched MeSH terms: Peptide Fragments/pharmacology; Peptide Fragments/therapeutic use
  20. Tam SW, Feng R, Lau WK, Law AC, Yeung PK, Chung SK
    J Biol Chem, 2019 08 16;294(33):12495-12506.
    PMID: 31248984 DOI: 10.1074/jbc.RA118.005155
    Endothelin-1 (ET-1) is a neuroactive peptide produced by neurons, reactive astrocytes, and endothelial cells in the brain. Elevated levels of ET-1 have been detected in the post-mortem brains of individuals with Alzheimer's disease (AD). We have previously demonstrated that overexpression of astrocytic ET-1 exacerbates memory deficits in aged mice or in APPK670/M671 mutant mice. However, the effects of ET-1 on neuronal dysfunction remain elusive. ET-1 has been reported to mediate superoxide formation in the vascular system via NADPH oxidase (NOX) and to regulate the actin cytoskeleton of cancer cell lines via the cofilin pathway. Interestingly, oxidative stress and cofilin activation were both reported to mediate one of the AD histopathologies, cofilin rod formation in neurons. This raises the possibility that ET-1 mediates neurodegeneration via oxidative stress- or cofilin activation-driven cofilin rod formation. Here, we demonstrate that exposure to 100 nm ET-1 or to a selective ET type B receptor (ETB) agonist (IRL1620) induces cofilin rod formation in dendrites of primary hippocampal neurons, accompanied by a loss of distal dendrites and a reduction in dendritic length. The 100 nm IRL1620 exposure induced superoxide formation and cofilin activation, which were abolished by pretreatment with a NOX inhibitor (5 μm VAS2870). Moreover, IRL1620-induced cofilin rod formation was partially abolished by pretreatment with a calcineurin inhibitor (100 nm FK506), which suppressed cofilin activation. In conclusion, our findings suggest a role for ETB in neurodegeneration by promoting cofilin rod formation and dendritic loss via NOX-driven superoxide formation and cofilin activation.
    Matched MeSH terms: Peptide Fragments/pharmacology
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