Dr Andrew Paterson

Rett syndrome (RTT) is a severe neurological disorder caused by mutations in the X-linked MECP2 gene, which encodes a methyl-CpG binding transcriptional repressor. Using the Mecp2-null mouse (an animal model for RTT) and differential display, we found that mice with neurological symptoms overexpress the nuclear gene for ubiquinol-cytochrome c reductase core protein 1 (Uqcrc1). Chromatin immunoprecipitation demonstrated that MeCP2 interacts with the Uqcrc1 promoter. Uqcrc1 encodes a subunit of mitochondrial respiratory complex III, and isolated mitochondria from the Mecp2-null brain showed elevated respiration rates associated with respiratory complex III and an overall reduction in coupling. A causal link between Uqcrc1 gene overexpression and enhanced complex III activity was established in neuroblastoma cells. Our findings raise the possibility that mitochondrial dysfunction contributes to pathology of the Mecp2-null mouse and may contribute to the long-known resemblance between Rett syndrome and certain mitochondrial disorders. Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Abstract

An imbalance in free radical production and removal is considered by many to be an important factor in the etiology of many degenerative diseases. Since mitochondria are a major source of free radicals, we have examined mitochondrial free radical production in relation to oxidative phosphorylation in PrP‐null mice. Quantitative electron paramagnetic resonance spectroscopy revealed up to a 70% increase in superoxide production from Complex I of submitochondrial particles prepared from PrP‐null mice. This was accompanied by elevated respiratory capacity through Complex I without any discernible alteration in respiratory efficiency. These differences are associated with changes in superoxide dismutase levels and defects in mitochondrial morphology, confirming previously reported results. Our results demonstrate a clear difference in free radical production and oxygen consumption by mitochondrial Complex I between PrP‐null mice and wild‐type controls, pointing to Complex I as a potential target for pathological change, suggesting similarities between prion‐related and other neurodegenerative diseases.

This systematic review aims to assess the reliability of contemporary research on water treatment with Moringa oleifera seeds, with emphases on methodological consistency and standardisation. Academic databases were browsed using 21 terms on a year-by-year basis (2014 – 2024); identification and screening were conducted between July 17th 2023 and December 9th 2024. Primary research reports featuring jar testing with M. oleifera seeds were included for data collection; reviews were excluded. Thirty-five fields were used to collect data from each included report. Data was synthesised by establishing causality between independent variables and outcomes, and then by comparing causalities between reports. Conflict of interest, research quality and risk of bias were assessed using Cochrane tools modified for in vitro laboratory studies. In total, 577 publications were identified, of which 50 were not duplicates. Of these, 25 were included for data collection and 25 were excluded. In total, 511 data points were collected and synthesised. No declared or apparent undeclared conflicts of interest were found. Nine reports received “highest quality” or “higher quality” judgments; 16 reports received “lower quality” or “lowest quality” judgements. Seven reports received “low risk of bias” judgements, 12 reports received “some concerns” bias judgements and six reports received “high risk of bias” judgements. Bias risk was most commonly associated with experimental design and missing data. The reliability of contemporary jar testing research was inconsistent, indicating a lack of standardisation. Variations in test water preparation, M. oleifera seed coagulant processing and jar test operational parameters affected treatment efficacies in unpredictable ways. Data reporting practices were often inadequate and experimental design was occasionally flawed. Researchers who used M. oleifera seed coagulants at appropriate concentrations and adhered to the three-stage model of coagulation, flocculation and sedimentation achieved turbidity reduction rates of 80 – 96%. Turbidity and microbiological reduction rates were comparable in three reports, but microbiological testing was uncommon. Saline-extracted coagulants outperformed aqueous extracts; aqueous extracts rarely outperformed dry M. oleifera seed powder. This is theoretically a result of modulation of protein–protein interactions in saline extracts and the tendency for self-association of M. oleifera cationic proteins in aqueous extracts. Based on their properties, M. oleifera cationic proteins are theorised to be lectins with hevein-like binding domains. These findings are significant because this technology has been in development for at least forty years, with early research into M. oleifera seed coagulation published in 1985. At present, the technology remains experimental due to perceived unreliability, unclear safety limits and limited innovation. Suggestions for future research, and for standardised testing and reporting, are made throughout this review with the aim of Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation advancing the technology beyond the experimental stage. If it is found to be a safe, effective and sustainable method of water purification, it may improve public health in rural communities of low-income countries. This outcome would support Targets 6.1, 6.a and 6.b of the United Nations sustainable development goals.

Hypochlorous acid and its acid-base counterpart, hypochlorite ions, produced under inflammatory conditions, may produce chloramides of glycosaminoglycans, these being significant components of the extracellular matrix (ECM). This may occur through the binding of myeloperoxidase directly to the glycosaminoglycans. The N-Cl group in the chloramides is a potential selective target for both reducing and oxidizing radicals, leading possibly to more efficient and damaging fragmentation of these biopolymers relative to the parent glycosaminoglycans. In this study, the fast reaction techniques of pulse radiolysis and nanosecond laser flash photolysis have been used to generate both oxidizing and reducing radicals to react with the chloramides of hyaluronan (HACl) and heparin (HepCl). The strong reducing formate radicals and hydrated electrons were found to react rapidly with both HACl and HepCl with rate constants of 1-1.7 × 10(8) and 0.7-1.2 × 10(8)M(-1)s(-1) for formate radicals and 2.2 × 10(9) and 7.2 × 10(8)M(-1)s(-1) for hydrated electrons, respectively. The spectral characteristics of the products of these reactions were identical and were consistent with initial attack at the N-Cl groups, followed by elimination of chloride ions to produce nitrogen-centered radicals, which rearrange subsequently and rapidly to produce C-2 radicals on the glucosamine moiety, supporting an earlier EPR study by M.D. Rees et al. (J. Am. Chem. Soc.125: 13719-13733; 2003). The oxidizing hydroxyl radicals also reacted rapidly with HACl and HepCl with rate constants of 2.2 × 10(8) and 1.6 × 10(8)M(-1)s(-1), with no evidence from these data for any degree of selective attack on the N-Cl group relative to the N-H groups and other sites of attack. The carbonate anion radicals were much slower with HACl and HepCl than hydroxyl radicals (1.0 × 10(5) and 8.0 × 10(4)M(-1)s(-1), respectively) but significantly faster than with the parent molecules (3.5 × 10(4) and 5.0 × 10(4)M(-1)s(-1), respectively). These findings suggest that these potential in vivo radicals may react in a site-specific manner with the N-Cl group in the glycosaminoglycan chloramides of the ECM, possibly to produce more efficient fragmentation. This is the first study therefore to conclusively demonstrate that reducing radicals react rapidly with glycosaminoglycan chloramides in a site-specific attack at the N-Cl group, probably to produce a 100% efficient biopolymer fragmentation process. Although less reactive, carbonate radicals, which may be produced in vivo via reactions of peroxynitrite with serum levels of carbon dioxide, also appear to react in a highly site-specific manner at the N-Cl group. It is not yet known if such site-specific attacks by this important in vivo species lead to a more efficient fragmentation of the biopolymers than would be expected for attack by the stronger oxidizing species, the hydroxyl radical. It is clear, however, that the N-Cl group formed under inflammatory conditions in the extracellular matrix does present a more likely target for both reactive oxygen species and reducing species than the N-H groups in the parent glycosaminoglycans.

Hypochlorous acid and its acid-base counterpart, hypochlorite ions, produced under inflammatory conditions, may produce chloramides of glycosaminoglycans, perhaps through the binding of myeloperoxidase directly to the glycosaminoglycans. The N-Cl group in the chloramides is a potential target for reducing species such as Cu(I) and superoxide radicals. Laser flash photolysis has been used here to obtain, for the first time, the rate constants for the direct reaction of superoxide radicals with the chloramides of hyaluronan and heparin. The rate constants were in the range 2.2-2.7 × 10(3)M(-1)s(-1). The rate constant for the reaction with the amino acid taurine was found to be much lower, at 3.5-4.0 × 10(2)M(-1)s(-1). This demonstration that superoxide anion radicals react directly with hyaluronan and heparin chloramides may support the mechanism first proposed by M.D. Rees et al. (Biochem. J.381, 175-184, 2004) for an efficient fragmentation of these glycosaminoglycans in the extracellular matrix under inflammatory conditions.

Hydrogen peroxide has important roles within cellular functions, as a prevalent form of Reactive Oxygen Species, detection within mammalian cells is of metabolic importance; typically requiring cell lysis or fluorescence-based methods to quantify. Herein, we explore the novel use of Prussian blue mediated, pad printed carbon electrodes to allow the indirect detection of cellular peroxides in bulk culture media, which facilitates non-invasive, real-time detection. Electrodes demonstrated capacity to detect H2O2 with a linear range of 1-200 μM in CMEM (R

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Hypochlorous acid (HOCl), produced in inflammatory conditions by the enzyme myeloperoxidase, and its anion hypochlorite (OCl(-)) exist in vivo at almost equal concentrations. Their reactions with hyaluronan and heparin (as a model for sulfated glycosaminoglycans in the extracellular matrix) have been studied as a function of pH. The major product in these reactions is the chloramide derivative of the glycosaminoglycans. Spectral, chloramide yield, and kinetic measurements show sharply contrasting behavior of heparin and hyaluronan and the data allow the calculation of second-order rate constants for the reactions of both HOCl and OCl(-) for all reaction pathways leading to the formation of chloramides and also oxidation products. By comparison with hyaluronan, it can be demonstrated that both N-sulfate and O-sulfate groups in heparin influence the proportions of these pathways in this glycosaminoglycan. Evidence is also given for further oxidation pathways involving a reaction of HOCl with the chloramide product of hyaluronan but not with heparin. The significance of these results for the mechanisms of inflammation, particularly for fragmentation of extracellular matrix glycosaminoglycans, is discussed.

Hypochlorous acid and its conjugate base, hypochlorite ions, produced under inflammatory conditions, may produce chloramides of glycosaminoglycans, these being significant components of the extracellular matrix (ECM). This may occur through the binding of myeloperoxidase directly to the glycosaminoglycans. The N-Cl group in the chloramides is a potential selective target for both reducing and oxidizing radicals, leading possibly to more efficient and damaging fragmentation of these biopolymers relative to the parent glycosaminoglycans. To investigate the effect of the N-Cl group, we used ionizing radiation to produce quantifiable concentrations of the reducing radicals, hydrated electron and superoxide radical, and also of the oxidizing radicals, hydroxyl, carbonate, and nitrogen dioxide, all of which were reacted with hyaluronan and heparin and their chloramides in this study. PAGE gels calibrated for molecular weight allowed the consequent fragmentation efficiencies of these radicals to be calculated. Hydrated electrons were shown to produce fragmentation efficiencies of 100 and 25% for hyaluronan chloramide (HACl) and heparin chloramide (HepCl), respectively. The role of the sulfate group in heparin in the reduction of fragmentation can be rationalized using mechanisms proposed by M.D. Rees et al. (J. Am. Chem. Soc.125:13719-13733; 2003), in which the initial formation of an amidyl radical leads rapidly to a C-2 radical on the glucosamine moiety. This is 100% efficient at causing glycosidic bond breakage in HACl but only 25% efficient in HepCl, the role of the sulfate group being to favor the nonfragmentary routes for the C-2 radical. The weaker reducing agent, the superoxide radical, did not cause fragmentation of either HACl or HepCl although kinetic reactivity had been demonstrated in earlier studies. Experiments using the oxidizing radicals, hydroxyl and carbonate, both potential in vivo species, showed significant increases in fragmentation efficiencies for both HACl and HepCl, relative to the parent molecules. The carbonate radical was shown to be involved in site-specific reactions at the N-Cl groups, reacting via abstraction of Cl, to produce the same amidyl radical produced by one-electron reductants such as the hydrated electron. As for the hydrated electrons, the data support fragmentation efficiencies of 100 and 29% for reaction of carbonate radicals at N-Cl for HACl and HepCl, respectively. For the weaker oxidant, nitrogen dioxide, no fragmentation was observed, probably because of a low kinetic reactivity and low reduction potential. It seems likely therefore that the N-Cl group can direct damage to extracellular matrix glycosaminoglycan chloramides, which may be produced under inflammatory conditions. The in vivo species, the carbonate radical, is also much more likely to be site-specific in its reactions with such components of the ECM than the hydroxyl radical.

This dataset contains the data, assessments and judgements required to replicate analyses and syntheses in the manuscript titled "A systematic review of water treatment with Moringa oleifera seeds: comparative analysis of jar testing methodologies and results" (Russell, Paterson and Pritchard, 2026). The table titled "PLOSwater_CollectedData_CSV_JJR_040626.csv" contains data collected from the 25 reports included in the systematic review; all of these reports conducted jar testing with coagulant(s) produced from the seeds of the tree species Moringa oleifera. A total of 511 data points were collected using 35 data fields. Data fields pertain to experimental design, methods of analyses and results. The data collection process was conducted in duplicate to ensure accuracy. The table concludes with comments on experimental outcomes (positive/negative) and concerns regarding experimental design. These data and comments were used in the synthesis of the systematic review; therefore, the authors chose to include the comments in the data table to allow third-party researchers to replicate the synthesis. Within the table, data fields are arranged into nine categories: 1. Test water properties: Type(s) of test water; Method(s) of adjusting test water turbidity; Pre-treatment turbidity; Pre-treatment pH. 2. M. oleifera seed handling: Source(s) of MO seeds; Method of species verification; Age of MO seeds at time of testing; Storage conditions of MO seeds. 3. M. oleifera seed processing: MO seed primary processing methods; MO seed defatting methods; MO seed secondary processing methods; MO seed tertiary processing methods; Final MO seed coagulant type(s). 4. Coagulant dosing concentrations: MO seed coagulant dosing concentration(s); Use of negative control (i.e. 0 mg/L); Use of positive control; Positive control dosing concentration(s). 5. Microbiological methods: Test organism species; Test organism concentration(s); Test organism recovery method(s). 6. Jar test operational parameters: Coagulation parameters; Flocculation parameters; Sedimentation parameters; Water sampling depth; Method(s) of data/statistical analysis. 7. Results: turbidity: Optimal turbidity reduction rate: MO seed coagulant(s); Optimal dose for turbidity reduction: MO seed coagulant(s); Optimal turbidity reduction rate: chemical coagulant(s); Optimal dose for turbidity reduction: chemical coagulant(s); Gravitational settling rate. 8. Results: other: Test organism concentration change: MO seed coagulant(s); Test organism concentration change: control sample(s); pH change: MO seed coagulant(s); pH change: chemical coagulant(s); Changes to dissolved residue concentrations. 9. Outcomes: Turbidity; Microbiology; pH; Dissolved residues; Additional notes. Author comments are exclusively contained within the “Additional notes” field at the conclusion of the table. The table titled "PLOSwater_ConflictOfInterest_Data_CSV_JJR_040626.csv" contains conflict of interest statements, funding statements, acknowledgement statements and data pertaining to author affiliations and institutes for each of the 25 reports included in the systematic review. The table concludes with conflict of interest judgements and judgement reasoning for each report. This assessment was conducted using Cochrane tools modified for in vitro laboratory studies. Conflict of interest judgements were used in the synthesis of the systematic review. The table titled "PLOSwater_ResearchQuality_Data_CSV_JJR_040626.csv" contains 11 signalling questions which were used to assess the quality of research of each of the 25 reports included in the systematic review. Each question is designed so that an answer of "yes" indicates positive research quality, "unclear" indicates minor quality loss and "no" indicates significant quality loss. Each report was assessed identically using all 11 signalling questions. Justification for answers of "unclear" and "no" are provided within the table. Reports are allocated an overall Quality Score (QS) and corresponding Quality Judgement (QJ) at the conclusion of the table. This assessment was conducted using Cochrane tools modified for in vitro laboratory studies. Research quality judgements (and associated reasoning) were used in the synthesis of the systematic review. The following signalling questions were used to assess research quality: Q-Q1: Are procedures fully described? Q-Q2: Are procedures appropriate? Q-Q3: Is the sample size/number of replicates appropriate? Q-Q4: Do procedures include appropriate control groups? Q-Q5: Are procedures applied identically to all groups? Q-Q6: Are procedures replicable? Q-Q7: Is analysis fully described? Q-Q8: Is analysis appropriate? Q-Q9: Is analysis applied identically to all groups? Q-Q10: Are pre-treatment data fully reported? Q-Q11: Are post-treatment data fully reported? The table titled "PLOSwater_RiskOfBias_Data_CSV_JJR_040626.csv" contains 10 signalling questions, categorised into three bias domains, which were used to assess the risk of bias of each of the 25 reports included in the systematic review. Within each bias domain, questions were answered sequentially (e.g. B-Q1.1, B-Q1.2 and then B-Q1.3). Each answer was then applied to the flow chart corresponding to its bias domain (see supporting figures “S1”, “S2” and “S3” within the manuscript). By answering all signalling questions within a bias domain, the corresponding flow chart was used to determine a risk of bias judgement for that bias domain (B-J1, B-J2 and B-J3). The table concludes with overall risk of bias judgements (B-J4) for each included report, as determined by the "Overall risk-of-bias judgement criteria" at the end of the table. This assessment was conducted using Cochrane tools modified for in vitro laboratory studies. Risk of bias judgements (and associated reasoning) were used in the synthesis of the systematic review. The following bias domains and signalling questions were used to assess risk of bias: Bias domain 1: Risk of bias due to experimental design and confounding factors B-Q1.1: Does the design of the experiment preclude bias? B-Q1.2: Are confounding factors identified, measured, controlled and reported? B-Q1.3: Do negative control data suggest confounding? Bias domain 2: Risk of bias due to missing data B-Q2.1: Are results data fully reported? B-Q2.2: Are data pertaining to confounding factors fully reported? B-Q2.3: Are missing data likely to affect the perception of treatment efficacy? Bias domain 3: Risk of bias due to selective reporting of data B-Q3.1a: Were data collected, analysed or presented using multiple methods in parallel? B-Q3.1b: Do conclusions consider data generated by all parallel methods? B-Q3.2: Are conclusions drawn from desirable data from a select sub-group or sub-groups? B-Q3.3: Are conclusions made in omission of undesirable data from a select sub-group or sub-groups? Assessments for conflict of interest, research quality and risk of bias were judged by two researchers in parallel using no automation tools; a third researcher was used to settle disagreements between the two principal judges.   File: PLOSwater_CollectedData_CSV_JJR_040626.csv Description: Methodological and results data collected from 25 reports for the synthesis of the systematic review titled "A systematic review of water treatment with Moringa oleifera seeds: comparative analysis of jar testing methodologies and results" (Russell, Paterson and Pritchard, in review). Variables • Missing values indicated with "N/A" • Alum - Aluminium sulphate (chemical coagulant) • BOD - Biological Oxygen Demand (measure of dissolved residue concentration) • CFU - Colony Forming Units (measure of microbiological concentration) • COD - Chemical Oxygen Demand (measure of dissolved residue concentration) • DOC - Dissolved Organic Carbon (measure of dissolved residue concentration) • MO - Moringa oleifera (tree species) • NTU - Nephelometric Turbidity Units (measure of turbidity in water) • PAC - Polyaluminum chloride (chemical coagulant) • RPM - Revolutions Per Minute (measure of mixing intensity of jar testing machine) • TDS - Total Dissolved Solids (measure of dissolved residue concentration) • TFC - Total Faecal Coliforms (measure of microbiological concentration) File: PLOSwater_ConflictOfInterest_Data_CSV_JJR_040626.csv Description: Conflict of interest assessments of 25 reports for the synthesis of the systematic review titled "A systematic review of water treatment with Moringa oleifera seeds: comparative analysis of jar testing methodologies and results" (Russell, Paterson and Pritchard, in review). Variables • Missing values indicated with "N/A" • No abbreviations in table File: PLOSwater_ResearchQuality_Data_CSV_JJR_040626.csv Description: Research quality assessments of 25 reports for the synthesis of the systematic review titled "A systematic review of water treatment with Moringa oleifera seeds: comparative analysis of jar testing methodologies and results" (Russell, Paterson and Pritchard, in review). Variables • No missing values in table • No abbreviations in table File: PLOSwater_RiskOfBias_Data_CSV_JJR_040626.csv Description: Risk of bias assessments of 25 reports for the synthesis of the systematic review titled "A systematic review of water treatment with Moringa oleifera seeds: comparative analysis of jar testing methodologies and results" (Russell, Paterson and Pritchard, in review). Variables • No missing values in table ("N/A" indicated non-applicable signalling question) • Alum - Aluminium sulphate (chemical coagulant) • BOD - Biological Oxygen Demand (measure of dissolved residue concentration) • CFU - Colony Forming Units (measure of microbiological concentration) • COD - Chemical Oxygen Demand (measure of dissolved residue concentration) • DOC - Dissolved Organic Carbon (measure of dissolved residue concentration) • MO - Moringa oleifera (tree species) • NTU - Nephelometric Turbidity Units (measure of turbidity in water) • PAC -

The measurement of pH is important throughout many biological systems, but there are limited available technologies to enable its periodical monitoring in the complex, small volume, media often used in cell culture experiments across a range of disciplines. Herein, pad printed electrodes are developed and characterised through modification with: a commercially available fullerene multiwall carbon nanotube composite applied in Nafion, casting of hydrophobic ubiquinone as a pH probe to provide the electrochemical signal, and coated in Polyethylene glycol to reduce fouling and potentially enhance biocompatibility, which together are proven to enable the determination of pH in cell culture media containing serum. The ubiquinone oxidation peak position (Epa) provided an indirect marker of pH across the applicable range of pH 6–9 (R2 = 0.9985, n = 15) in complete DMEM. The electrochemical behaviour of these sensors was also proven to be robust; retaining their ability to measure pH in cell culture media supplemented with serum up to 20% (v/v) [encompassing the range commonly employed in cell culture], cycled > 100 times in 10% serum containing media and maintain > 60% functionality after 5 day incubation in a 10% serum containing medium. Overall, this proof of concept research highlights the potential applicability of this, or similar, electrochemical approaches to enable to detection or monitoring of pH in complex cell culture media.

Propolis is a varied combination of plant resins scavenged by worker bees for use within the hive. A central challenge lies in establishing correlations between its chemical composition and biological activities. This study aimed to investigate the biological activity of propolis using three global samples relating chemical composition and the potential interaction with antibiotics using an industry sample of propolis. Methods utilised included microbial, biochemical, and RNA expression analyses. HPLC data showed notable disparities in concentrations of key propolis constituents between regions, with North Portuguese (NP) propolis exhibiting the highest levels of all standards compared to those of UK (Leeds) and Brazilian origin. Antimicrobial testing revealed that the propolis MIC was lower for gram-positive bacteria; S. aureus and E. faecalis (MIC 0.03-0.06% for both UK and NP) when compared to gram-negative bacteria, with E. coli exhibiting an MIC of 0.125% and P. aeruginosa 1%. Sub-inhibitory concentrations of propolis extended the lag phase most notably against S. aureus and E. faecalis. Biofilm assays demonstrated propolis' efficacy in inhibiting biofilm formation, whilst kill curves demonstrated bactericidal activity across all three propolis samples and antioxidant testing revealed potent antioxidant activity, with NP exhibiting the greatest activity. Evaluation of propolis-antibiotic interactions revealed increased zones of inhibition for MRSA and MSSA isolates when combined with 6 out of 8 antibiotics tested. E-tests confirmed a MIC reduction. Chequerboard assays revealed the nature of the relationship. RNA sequencing showed evidence of bacterial stress, with downregulation of cellular metabolic processes. In conclusion, findings highlight the multifaceted nature of propolis' biological activities, such as the exhibition of antimicrobial activity, however HPLC analysis of 13 standards is not sufficient to fully predict biological activity. Chequerboard assays confirmed either a synergistic or additive activity with three antibiotics highlighting the potential of propolis to be used in the fight against antibiotic resistance.

Evidence has long underpinned the formyl peptide receptors (FPRs) as key receptors in the chemotaxis and pro-inflammation of immune cells. Yet, recent evidence also implicated the FPRs as necessary in the resolution of inflammation (ROI), and the return to homeostasis following disease or injury, in wider physiological settings. The expression of FPRs on multiple cells of the neurogenic niche, i.e., neuronal cells, has led to the question: are FPRs involved in neurogenesis? Here, a systematic review has been undertaken and current evidence was evaluated in four criteria essential to neurogenesis and neuroregeneration. The outcomes revealed an overall small body of evidence with recommendations subsequently made. To address limited ligand diversity amongst currently available evidence, in vitro investigation was performed with synthetic FPR agonists, TC FPR 43 and quin C1, in both mouse and human cell lines, and concluded support for a role of FPRs in neurite outgrowth. Bioinformatics has also been employed towards the discovery of novel endogenous ligands and signalling pathways, in which FPRs may promote aspects of neurogenesis and neuroregeneration. The outcomes of this may be key to understand FPRs role in human neurogenesis. Finally, aptamers were generated to FPR1 and FPR2 to increase the range of FPR ligands for potential use in neuronal drug discovery and working towards therapeutics that can cross the blood brain barrier. The ssDNA sequences are presented within. To summarise, this thesis supports a role of FPRs in neurogenesis whilst recommending many directions to strengthen current evidence and understanding. Overall, the FPRs may be suitable targets in conditions such as traumatic brain injury and neurodegenerative disease, where neurogenesis and neuroregeneration would improve patient outcome.

The N-formyl peptide receptors (FPRs) have been identified within neuronal tissues and may serve as yet undetermined functions within the nervous system. The FPRs have been implicated in the progression and invasiveness of neuroblastoma and other cancers. In this study the effects of the synthetic FPR agonist FPRa14, FPR antagonists and FPR knockdown using siRNA on mouse neuroblastoma neuro2a (N2a) cell differentiation plus toxicity were examined. The FPRa14 (1-10μM) was found to induce a significant dose-dependent differentiation response in mouse neuroblastoma N2a cells. Interestingly, three distinct differentiated morphologies were observed, with two non-archetypal forms observed at the higher FPRa14 concentrations. These three forms were also observed in the human neuroblastoma cell-lines IMR-32 and SH-SY5Y when exposed to 100μM FPRa14. In N2a cells combined knockdown of FPR1 and FPR2 using siRNA inhibited the differentiation response to FPRa14, suggesting involvement of both receptor subtypes. Pre-incubating N2a cultures with the FPR1 antagonists Boc-MLF and cyclosporin H significantly reduced FPRa14-induced differentiation to near baseline levels. Meanwhile, the FPR2 antagonist WRW4 had no significant effect on FPRa14-induced N2a differentiation. These results suggest that the N2a differentiation response observed has an FPR1-dependent component. Toxicity of FPRa14 was only observed at higher concentrations. All three antagonists used blocked FPRa14-induced toxicity, whilst only siRNA knockdown of FPR2 reduced toxicity. This suggests that the toxicity and differentiation involve different mechanisms. The demonstration of neuronal differentiation mediated via FPRs in this study represents a significant finding and suggests a role for FPRs in the CNS. This finding could potentially lead to novel therapies for a range of neurological conditions including neuroblastoma, Alzheimer's disease, Parkinson's disease and neuropathic pain. Furthermore, this could represent a potential avenue for neuronal regeneration therapies.

N -formyl peptide receptors (FPRs) were first identified upon phagocytic leukocytes, but more than four decades of research has unearthed a plethora of non-myeloid roles for this receptor family. FPRs are expressed within neuronal tissues and markedly in the central nervous system, where FPR interactions with endogenous ligands have been implicated in the pathophysiology of several neurodegenerative diseases including Alzheimer’s disease and Parkinson’s disease, as well as neurological cancers such as neuroblastoma. Whilst the homeostatic function of FPRs in the nervous system is currently undefined, a variety of novel physiological roles for this receptor family in the neuronal context have been posited in both human and animal settings. Rapid developments in recent years have implicated FPRs in the process of neurogenesis and neuronal differentiation which, upon greater characterisation, could represent a novel pharmacological target for neuronal regeneration therapies that may be used in the treatment of brain/spinal cord injury, stroke and neurodegeneration. This review aims to summarize the recent progress made to determine the physiological role of FPRs in a neuronal setting, and to put forward a case for FPRs as a novel pharmacological target for conditions of the nervous system, and for their potential to open the door to novel neuronal regeneration therapies.