The Art of War with Pseudomonas aeruginosa: Targeting Mex Efflux Pumps Directly to Strategically Enhance Antipseudomonal Drug Efficacy.

Pseudomonas aeruginosa (P. aeruginosa) poses a grave clinical challenge due to its multidrug resistance (MDR) phenotype, leading to severe and life-threatening infections. This bacterium exhibits both intrinsic resistance to various antipseudomonal agents and acquired resistance against nearly all available antibiotics, contributing to its MDR phenotype. Multiple mechanisms, including enzyme production, loss of outer membrane proteins, target mutations, and multidrug efflux systems, contribute to its antimicrobial resistance. The clinical importance of addressing MDR in P. aeruginosa is paramount, and one pivotal determinant is the resistance-nodulation-division (RND) family of drug/proton antiporters, notably the Mex efflux pumps. These pumps function as crucial defenders, reinforcing the emergence of extensively drug-resistant (XDR) and pandrug-resistant (PDR) strains, which underscores the urgency of the situation. Overcoming this challenge necessitates the exploration and development of potent efflux pump inhibitors (EPIs) to restore the efficacy of existing antipseudomonal drugs. By effectively countering or bypassing efflux activities, EPIs hold tremendous potential for restoring the antibacterial activity against P. aeruginosa and other Gram-negative pathogens. This review focuses on concurrent MDR, highlighting the clinical significance of efflux pumps, particularly the Mex efflux pumps, in driving MDR. It explores promising EPIs and delves into the structural characteristics of the MexB subunit and its substrate binding sites.

Involvement of indoleamine 2, 3-dioxygenase (IDO) and brain-derived neurotrophic factor (BDNF) in the neuroprotective mechanisms of ferulic acid against depressive-like behaviour.

OBJECTIVE: Ferulic acid (FA) is a common food ingredient that is abundantly present in various routinely consumed food and beverages. Like many cinnamic acid derivatives, FA produces wide-ranging effects in a dose-dependent manner and various studies link FA consumption with reduced risk of depressive disorders. The aim of this study was to exploit the neuroprotective mechanisms of FA including indoleamine 2,3-dioxygenase (IDO), brain-derived neurotrophic factor (BDNF), and other pro-inflammatory cytokines by employing lipopolysaccharide (LPS)-induced depressive-like behaviour model. METHODS: C57BL/6J male mice were divided into 4 groups consisting of saline (SAL), LPS, FA and Imipramine (IMI). Animals were pretreated orally with FA (10 mg/kg) and IMI (10 mg/kg) for 21 days once daily and all groups except SAL were challenged with LPS (0.83 mg/kg) intraperitoneally on day 21. RESULTS: LPS administration produced a biphasic change in the behaviour of the animals where the animals lost a significant weight and express high immobility time at 24 h. Proinflammatory cytokines including, TNF-α, IL-6, IL-1ß, and IFN-γ were significantly increased along with increased lipid peroxidation and reduced BDNF. Furthermore, the increased kynurenine to tryptophan ratio was indicative of elevated IDO activity. CONCLUSION: The results of this study emphasise that low dose of FA is effective in attenuating depressive-like behaviour by modulating IDO, BDNF and reducing neuroinflammation.

Gamification in pharmacy education: a systematic quantitative literature review.

OBJECTIVES: Gamification involves applying game attributes to non-game contexts and its educational use is increasing. It is essential to review the outcomes and the efficacy of gamification to identify evidence to support its use in pharmacy education. THIS ARTICLE: systematically and quantitatively reviews and evaluates the alignment of learning outcomes and the quality of peer-reviewed literature reporting gamification in pharmacy education. KEY FINDINGS: A literature search was undertaken in February 2022 using CINAHL Complete, MEDLINE, Science Direct, Scopus and ERIC databases, via keywords (game* OR gaming OR gamif*) AND pharmac* AND education. Google Scholar was searched using 'gamification of pharmacy education' and 'serious games in pharmacy education'. Data extracted included type of gamified intervention, mode of delivery, game fidelity, intended learning outcomes and outcomes reported. Quality assessments aligned with key aspects of the SQUIRE-EDU Reporting Guidelines. Of 759 abstracts and 95 full-text papers assessed, 66 articles met the inclusion criteria. They described gamification from 12 countries in the education of 8272 pharmacy and health professional students. Gamified interventions ranged from board games to immersive simulations, with escape rooms most frequently reported. Reporting quality was inconsistent, with observed misalignment between intended learning outcomes and outcomes reported, an apparent overreliance on student perceptions as primary data and a lack of reference to reporting guidelines. SUMMARY: Gamification is included in the curricula of many pharmacy degrees, across multiple subject areas. This review identified evidence gaps and reinforces the need for improved quality of gamification research, critical alignment of learning outcomes with evaluation, and use of reporting guidelines.

Optimising database searching in pharmacy education.

OBJECTIVES: To determine the effectiveness of databases in a pharmacy education literature search. METHODS: Six databases (CINAHL, ERIC, Google Scholar, Ovid MEDLINE, Science Direct and Scopus) were compared for effectiveness in identifying pharmacy education literature. Articles were coded for database of retrieval and results cross-referenced. Sensitivity, precision and number of unique retrievals were calculated. KEY FINDINGS: Scopus yielded the highest sensitivity (65%) and precision (47%). The combination of three databases (Scopus, Science Direct and Google Scholar) identified 97% (n = 64) of 66 relevant articles. CONCLUSIONS: Pharmacy education literature searches require more than one database, ideally Scopus, Science Direct and Google Scholar.

Impact of a gamified simulation on pharmacy students' self-assessed competencies.

INTRODUCTION: Competency-based pharmacist education develops robust professional identities and prepares graduates for future practice to ensure optimal patient outcomes. An extended gamified simulation was developed as a capstone activity for a new Australian Bachelor of Pharmacy (BPharm) program. The simulation was designed to consolidate students' knowledge, skills, and behaviors from prior learning. This research aimed to explore whether participation in an extended gamified simulation could influence pharmacy students' perceptions of their professional competencies. METHODS: Data were collected over three years to compare a superseded Master of Pharmacy (MPharm) program with an incoming BPharm program. Final year students were invited to self-assess their professional competencies at the start and end of their final semester of study, using a digital self-assessment tool which replicated Australia's National Competency Standards Framework for Pharmacists. Participants rated their own competency against the 26 competency standards across five domains on a five-point Likert scale (not at all competent to very competent). This provided pre- and post-data to compare the simulation (BPharm intervention) and a traditional semester (MPharm comparison), in addition to final course grades. RESULTS: From 2016 to 2019, 85 (90.4%) of 94 intervention and 50 (83.3%) of 60 comparison students completed the self-assessment of professional competencies. Participation in the gamified simulation significantly improved students' pharmacotherapeutics grades and pre-post change scores for seven of the 26 competency standards, two of the five domains, and all domains combined of the National Competency Standards. CONCLUSIONS: An extended, gamified simulation enhances the development of pharmacy students' self-assessed professional competencies.

Putative involvement of sirtuin modulators in LPS-induced sickness behaviour in mice.

NAD+-dependent histone deacetylases (sirtuins 1-7) have been shown to be involved in various pathophysiological conditions including their involvement in cardiovascular, cancerous, neurodegenerative, immune dysregulation and inflammatory conditions. This study investigates the inflammomodulatory potential of resveratrol (RES), a sirtuin activator and sirtinol (SIR), a sirtuin inhibitor in lipopolysaccharide (LPS)-induced model of sickness behaviour in mice. Male Swiss albino mice were divided into five groups (n = 6) consisting of saline (SAL), LPS, RES, SIR, and fluoxetine (FLU) respectively, each group except LPS was prepared by intraperitoneally (i.p.) administration of SAL (10 mL/kg), RES (50 mg/kg), SIR (2 mg/kg) and FLU (10 mg/kg). Thirty minutes after the treatments, all the groups, except SAL were administered LPS (2 mg/kg, i.p.). The behavioural assays including, open field test, forced swim test, and tail suspension tests were conducted 1 h after LPS challenge. LPS administration significantly reduced the locomotor activity along with inducing a state of high immobility and that was prevented by pretreatment with RES and SIR. Further, various proinflammatory cytokines (TNF-α, IL-6, and IL-1ß), and oxidative stress markers (MDA and GSH) were found to be significantly elevated in the brain homogenates after LPS treatment. SIR pretreatment abrogated the LPS-induced neuroinflammatory and oxidative stress changes, whereas RES was only effective in reducing the oxidative stress and TNF-α levels. The results of this study speculate that the role of SIRT modulators in neuroinflammatory conditions could vary with their dose, regimen and chemical properties. Further studies with detailed molecular and pharmacokinetic profiling will be needed to explore their therapeutic potentials.

Virtualized Gamified Pharmacy Simulation during COVID-19.

Extended and immersive gamified pharmacy simulation has been demonstrated to provide transformative learning in pharmacy education, preparing graduates for real-world practice. An international consortium of universities has implemented local adaptations of the Pharmacy Game into their curricula. From early 2020, pharmacy academics modified the delivery of gamified simulation in response to the COVID-19 pandemic, while still aiming to deliver the important learning outcomes of enhanced communication, collaboration, confidence and competence. Australian universities went into full lockdown from March 2020, and the critical gamified simulation at Griffith University was delivered entirely virtually in 2020. An array of synchronous and asynchronous approaches and software platforms was employed, including Microsoft Teams, Forms and Stream plus the online interview platform Big Interview. These allowed for the simulation activities, including dispensing, counselling and clinical cases, to be conducted by students online. In 2021, Griffith University conducted hybrid delivery of its Pharmacy Game, balancing student participation both in person and online. Microsoft Power Apps was added to the hosting platform to enhance the simulation interface, and Power Virtual Agent artificial intelligence chatbots, with natural language processing, were used to enable asynchronous clinical interaction. The combination of learning technologies provided the means to deliver successful gamified simulation in the virtual and hybrid environments while still achieving outstanding learning outcomes from the capstone activity. This paper details the technologies used to virtualize the Australian Pharmacy Game and the analytics available to educators to assess student participation, engagement and performance.

Learner attitudes towards a virtual microbiology simulation for pharmacy student education.

INTRODUCTION: Simulation for education has become popular, but much literature on this modality fails to critically examine the learner's experience, focusing instead on learning outcomes. Learner attitudes should be scrutinised and monitored to appraise a technology-enhanced learning experience as student perceived educational benefits of technology-enhanced learning is reported to be more important than the intrinsic characteristics of any particular medium or tool. This study sought to evaluate pharmacy students' attitudes toward a virtual microbiology simulation. METHODS: The virtual microbiology simulation (VUMIE) was compared with a traditional wet laboratory (lab) in a second-year integrated pharmacotherapeutics course for bachelor of pharmacy students. Data were collected using surveys deployed at baseline (pre-intervention), post-intervention (VUMIE or wet lab), and endpoint (post-interventions). Statistical and qualitative thematic analyses were performed. RESULTS: Learners found the simulation valuable, and outcomes suggest that it is possible for technology-enhanced learning activities to replace face-to-face instruction to some extent, which may be useful given the current challenges with in-person education resulting from COVID-19. More students reported a specific preference for the wet lab rather than VUMIE. CONCLUSIONS: Although technology-enhanced simulation can produce a similar learning experience to a traditional wet lab, this evidence is not sufficient to completely replace the traditional lab experience for clinical courses of study. Technology-enhanced simulation could be considered for just-in-time training before exposure to traditional lab activities, for specific skill acquisition using deliberate practice, and perhaps for standardised assessment for clinical microbiology education.

Remedial effects of caffeine against depressive-like behaviour in mice by modulation of neuroinflammation and BDNF.

Objective: Caffeine (CAF) is one of the most commonly consumed nutritional stimulant in beverages. Interestingly, CAF produces varied effects in a dose-dependent manner, and that makes it one of the most controversial nutritional ingredients. Various studies have linked CAF consumption and reduced risk of depressive disorders. The aim of this study was to investigate the effect of CAF on lipopolysaccharide (LPS)-induced neuroinflammation and depressive-like behaviour.Methods: C57BL/6J male mice were divided into four groups consisting of saline (SAL), LPS, CAF and Imipramine (IMI). Animals were pretreated orally with CAF (10 mg/kg) and IMI (10 mg/kg) for 14 days once daily and all groups except SAL were challenged with LPS (0.83 mg/kg) intraperitoneally on day 14.Results: LPS produced a biphasic behavioural response with a significantly high immobility time and weight loss after 24 h. The brain cytokines (TNF-α, IL-6, IL-1ß, and IFN-γ) levels were remarkably high, along with increased lipid peroxidation and reduced Brain Derived Neurotrophic Factor (BDNF). These biochemical and behavioural changes were significantly alleviated by CAF and IMI chronic treatment.Conclusion: The results of this study implicate that mild-moderate consumption of CAF could impart anti-inflammatory properties under neuroinflammatory conditions by modulating the cytokine and neurotrophic mechanisms.

Investigating the Convergent Mechanisms between Major Depressive Disorder and Parkinson's Disease.

Major depressive disorder (MDD) affects more than cognition, having a temporal relationship with neuroinflammatory pathways of Parkinson's disease (PD). Although this association is supported by epidemiological and clinical studies, the underlying mechanisms are unclear. Microglia and astrocytes play crucial roles in the pathophysiology of both MDD and PD. In PD, these cells can be activated by misfolded forms of the protein α-synuclein to release cytokines that can interact with multiple different physiological processes to produce depressive symptoms, including monoamine transport and availability, the hypothalamus-pituitary axis, and neurogenesis. In MDD, glial cell activation can be induced by peripheral inflammatory agents that cross the blood-brain barrier and/or c-Fos signalling from neurons. The resulting neuroinflammation can cause neurodegeneration due to oxidative stress and glutamate excitotoxicity, contributing to PD pathology. Astrocytes are another major link due to their recognized role in the glymphatic clearance mechanism. Research suggesting that MDD causes astrocytic destruction or structural atrophy highlights the possibility that accumulation of α-synuclein in the brain is facilitated as the brain cannot adequately clear the protein aggregates. This review examines research into the overlapping pathophysiology of MDD and PD with particular focus on the roles of glial cells and neuroinflammation.

Experiential Learning in a Gamified Pharmacy Simulation: A Qualitative Exploration Guided by Semantic Analysis.

Experiential learning is an important component of pharmacist education and is primarily achieved through supervised placement or simulation. This study explored senior pharmacy students' experiential learning in an extended, immersive, gamified simulation, conducted as a capstone learning activity toward the end of their final year of study, consolidating all prior learning and preparing students for intern practice. The simulation aimed to enhance student confidence, competence and collaboration. The three-week activity involved student teams competitively managing simulated pharmacies, assuming the role of pharmacists to complete all scaffolded assessments, including dispensing prescriptions, clinical cases, verbal counselling, simulated patient cases, interprofessional collaboration, and assignments. Assessments were marked continuously, with consequences of practice acknowledged through gain or loss of 'patients' for the pharmacy. From 2016 to 2018, 123 students completed multiple individual reflective journals (n = 733). Reflective journals were analyzed to explore the student experience, using a mixed methods approach. Initial Leximancer® 4.51 semantic analysis guided thematic analysis, conducted in NVivo® 12. The major themes that emerged were teamwork, patient-centeredness, medicines provision, future practice, and the learning experience. Student participants reported an intense and emotional experience in the gamified simulation, with many students revealing transformation in their skills, behaviors and attitudes over its duration.

In vitro cytotoxicity of montelukast in HAPI and SH-SY5Y cells.

Montelukast is a cysteinyl leukotriene (CysLT) receptor antagonist with efficacy against a variety of diseases, including asthma and inflammation-related conditions. However, various neuropsychiatric events (NEs) suspected to be related to montelukast have been reported recently, with limited understanding on their association and underlying mechanisms. This study aimed to investigate whether montelukast can induce neuroinflammation and neurotoxicity in microglial HAPI cells and neural SH-SY5Y cells. The present study also compared the effects of montelukast with a 5-lipoxygenase inhibitor (zileuton) and a cyclooxygenase-2 inhibitor (celecoxib) to better understand modulation of related pathways. HAPI or SH-SY5Y cells were treated with the indicated drugs (3.125 µM-100 µM) for 24 h to investigate drug-induced neuroinflammation and neurotoxicity. Montelukast induced cytotoxicity in HAPI cells (50-100 µM), accompanied with caspase-3/7 activation, prostaglandin E2 (PGE2) release, and reactive oxygen species (ROS) production. Whilst both montelukast and zileuton down-regulated CysLT release in HAPI cells, zileuton did not significantly affect cell viability or inflammatory and oxidative factors. Celecoxib decreased HAPI cell viability (6.25-100 µM), accompanied with increasing caspase-3/7 activation and ROS production, but in contrast to montelukast increased CysLT release and decreased PGE2 production. Similar to observations in HAPI cells, both montelukast and celecoxib (50-100 µM) but not zileuton produced toxicity in SH-SY5Y neuroblastoma cells. Similarly, CM from HAPI cells treated with either montelukast or zileuton produced toxicity in SH-SY5Y cells. The results of the current study show the capability of montelukast to directly induce toxicity and inflammation in HAPI cells, possibly through the involvement of PGE2 and ROS, and toxicity in undifferentiated SH-SY5Y neuroblastoma cells. The current study highlights the importance of consideration between benefit and risk of montelukast usage and provides references for future investigation on decreasing montelukast-related NEs.

Women Experience the Same Ergogenic Response to Caffeine as Men.

PURPOSE: This study aimed to determine whether 1) consumption of caffeine improves endurance cycling performance in women and 2) sex differences exist in the magnitude of the ergogenic and plasma responses to caffeine supplementation. METHODS: Twenty-seven (11 women and 16 men) endurance-trained cyclists and triathletes participated in this randomized, double-blind, placebo-controlled, crossover study. Participants completed an incremental exercise test to exhaustion, two familiarization trials, and two performance trials. Ninety minutes before the performance trials, participants ingested opaque capsules containing either 3 mg·kg body mass of anhydrous caffeine or a placebo. They then completed a set amount of work (75% of peak sustainable power output) in the fastest possible time. Plasma was sampled at baseline, preexercise, and postexercise for caffeine. Strict standardization and verification of diet, hydration, training volume and intensity, and contraceptive hormone phase (for women) were implemented. RESULTS: Performance time was significantly improved after caffeine administration in women (placebo: 3863 ± 419 s, caffeine: 3757 ± 312 s; P = 0.03) and men (placebo: 3903 ± 341 s, caffeine: 3734 ± 287 s; P < 0.001). The magnitude of performance improvement was similar for women (mean = 4.3%, 95% CI = 0.4%-8.2%) and men (4.6%, 2.3%-6.8%). Plasma caffeine concentrations were similar between sexes before exercise, but significantly greater in women after exercise (P < 0.001). CONCLUSIONS: Ingestion of 3 mg·kg body mass of caffeine enhanced endurance exercise performance in women. The magnitude of the performance enhancement observed in women was similar to that of men, despite significantly greater plasma caffeine concentrations after exercise in women. These results suggest that the current recommendations for caffeine intake (i.e., 3-6 mg·kg caffeine before exercise to enhance endurance performance), which are derived almost exclusively from studies on men, may also be applicable to women.

Epothilone D inhibits microglia-mediated spread of alpha-synuclein aggregates.

Multiple System Atrophy (MSA) is a progressive neurodegenerative disease characterized by chronic neuroinflammation and widespread α-synuclein (α-syn) cytoplasmic inclusions. Neuroinflammation associated with microglial cells is typically located in brain regions with α-syn deposits. The potential link between microglial cell migration and the transport of pathological α-syn protein in MSA was investigated. Qualitative analysis via immunofluorescence of MSA cases (n = 4) revealed microglial cells bearing α-syn inclusions distal from oligodendrocytes bearing α-syn cytoplasmic inclusions, as well as close interactions between microglia and oligodendrocytes bearing α-syn, suggestive of a potential transfer mechanism between microglia and α-syn bearing cells in MSA and the possibility of microglia acting as a mobile vehicle to spread α-syn between anatomically connected brain regions. Further In vitro experiments using microglial-like differentiated THP-1 cells were conducted to investigate if microglial cells could act as potential transporters of α-syn. Monomeric or aggregated α-syn was immobilized at the centre of glass coverslips and treated with either cell free medium, undifferentiated THP-1 cells or microglial-like phorbol-12-myristate-13-acetate differentiated THP-1 cells (48 h; n = 3). A significant difference in residual immobilized α-syn density was observed between cell free controls and differentiated (p = 0.016) as well as undifferentiated and differentiated THP-1 cells (p = 0.032) when analysed by quantitative immunofluorescence. Furthermore, a significantly greater proportion of differentiated cells were observed bearing α-syn aggregates distal from the immobilized protein than their non-differentiated counterparts (p = 0.025). Similar results were observed with Highly Aggressive Proliferating Immortalised (HAPI) microglial cells, with cells exposed to aggregated α-syn yielding lower residual immobilized α-syn (p = 0.004) and a higher proportion of α-syn positive distal cells (p = 0.001) than cells exposed to monomeric α-syn. Co-treatment of THP-1 groups with the tubulin depolymerisation inhibitor, Epothilone D (EpoD; 10 nM), was conducted to investigate if inhibition of microtubule activity had an effect on cell migration and residual immobilized α-syn density. There was a significant increase in both residual immobilized α-syn between EpoD treated and non-treated differentiated cells exposed to monomeric (p = 0.037) and aggregated (p = 0.018) α-syn, but not with undifferentiated cells. Differentiated THP-1 cells exposed to immobilized aggregated α-syn showed a significant difference in the proportion of distal aggregate bearing cells between EpoD treated and untreated (p = 0.027). The results suggest microglia could play a role in α-syn transport in MSA, a role which could potentially be inhibited therapeutically by EpoD.

Interplay between adenosine receptor antagonist and cyclooxygenase inhibitor in haloperidol-induced extrapyramidal effects in mice.

Antipsychotic drugs are the mainstay of psychotic disorders. The 'typical' antipsychotic agents are commonly employed for the positive symptoms of schizophrenia, though at an expense of extrapyramidal side effects (EPS). In the present study, we employed haloperidol (HP)-induced catalepsy model in mice to evaluate the role of adenosine receptor antagonist and cyclooxygenase (COX) enzyme inhibitor in the amelioration of EPS. HP produced a full blown catalepsy, akinesia and a significant impairment in locomotion and antioxidant status. Pre-treatment with COX inhibitor; naproxen (NPx) and adenosine receptor antagonist; caffeine (CAF), showed a significant impact on HP-induced cataleptic symptoms. Adenosine exerts pivotal control on dopaminergic receptors and is also involved in receptor internalization and recycling. On the other hand, prostaglandins (PGs) are implicated as neuro-inflammatory molecules released due to microglial activation in both Parkinson's disease (PD) and antipsychotics-induced EPS. The involvement of these neuroeffector molecules has led to the possibility of use of CAF and COX inhibitors as therapeutic approaches to reduce the EPS burden of antipsychotic drugs. Both these pathways seem to be interlinked to each other, where adenosine modulates the formation of PGs through transcriptional modulation of COXs. We observed an additive effect with combined treatment of NPx and CAF against HP-induced movement disorder. These effects lead us to propose that neuromodulatory pathways of dopaminergic circuitry need to be explored for further understanding and utilizing the full therapeutic potential of antipsychotic agents.

Pyocyanin induces systemic oxidative stress, inflammation and behavioral changes in vivo.

Pyocyanin (PCN) is a virulence factor secreted by Pseudomonas aeruginosa (P. aeruginosa) that has been shown to have numerous toxic effects in both in vitro and in vivo studies. Such toxicities include pro-inflammatory and pro-oxidant mediated responses. It is hypothesized that PCN can cross biological membranes and reach the systemic circulation, but no previous studies have investigated this. The aim of this study was, therefore, to quantify PCN in plasma and assess if systemic responses were occurring after localized intranasal administration in C57BL/6 J mice. This was achieved through the plasma quantification of PCN and assessment of changes to behavior using two commonly used tests, the forced swimming test and the open field test. Furthermore, evidence of systemic oxidative stress and inflammation was measured using malondialdehyde (MDA) and TNF-α post PCN exposure. PCN was found to cross into systemic circulation but in a variable manner. Furthermore, significant increases in plasma TNF-α and MDA (both p < 0.001) were observed along with changes in behavior indicative of systemic inflammatory responses.

Modulation of chemotherapy-induced cytotoxicity in SH-SY5Y neuroblastoma cells by caffeine and chlorogenic acid.

Chemotherapy is an important treatment modality for malignancy but is limited by significant toxicity and it susceptibility to numerous drug interactions. While the interacting effects with medications are well known, there is limited evidence on the interaction with commonly consumed food and natural products. The aim of this study was to evaluate the bioactive constituents of coffee (caffeine and chlorogenic acid) on the cytotoxicity of doxorubicin, gemcitabine, and paclitaxel in vitro. Pretreatment with caffeine (100 nM and 10 µM) sensitized SH-SY5Y cells to doxorubicin-induced toxicity and increased apoptosis and sensitized PC3 cells to gemcitabine-induced toxicity. Pretreatment with 10 µM caffeine decreased total cell reactive oxygen species (ROS) production but increased mitochondrial ROS production. In contrast, caffeine (10 nM and 10 µM) protected cells against gemcitabine-induced toxicity and apoptosis. Similarly, 1 µM and 10 µM caffeine protected cells against paclitaxel-induced toxicity and mitochondrial ROS production. Chlorogenic acid had no effect on chemotherapy-induced toxicity in SH-SY5Y cells. In conclusion, this study provides preliminary evidence that caffeine, not chlorogenic acid, modulates the cytotoxicity of doxorubicin, gemcitabine, and paclitaxel in SH-SY5Y cells via different mechanisms.

Medications influencing central cholinergic pathways affect fixation stability, saccadic response time and associated eye movement dynamics during a temporally-cued visual reaction time task.

RATIONALE: Anticholinergic medications largely exert their effects due to actions on the muscarinic receptor, which mediates the functions of acetylcholine in the peripheral and central nervous systems. In the central nervous system, acetylcholine plays an important role in the modulation of movement. OBJECTIVE: This study investigated the effects of over-the-counter medications with varying degrees of central anticholinergic properties on fixation stability, saccadic response time and the dynamics associated with this eye movement during a temporally-cued visual reaction time task, in order to establish the significance of central cholinergic pathways in influencing eye movements during reaction time tasks. METHODS: Twenty-two participants were recruited into the placebo-controlled, human double-blind, four-way crossover investigation. Eye tracking technology recorded eye movements while participants reacted to visual stimuli following temporally informative and uninformative cues. The task was performed pre-ingestion as well as 0.5 and 2 h post-ingestion of promethazine hydrochloride (strong centrally acting anticholinergic), hyoscine hydrobromide (moderate centrally acting anticholinergic), hyoscine butylbromide (anticholinergic devoid of central properties) and a placebo. RESULTS: Promethazine decreased fixation stability during the reaction time task. In addition, promethazine was the only drug to increase saccadic response time during temporally informative and uninformative cued trials, whereby effects on response time were more pronounced following temporally informative cues. Promethazine also decreased saccadic amplitude and increased saccadic duration during the temporally-cued reaction time task. CONCLUSION: Collectively, the results of the study highlight the significant role that central cholinergic pathways play in the control of eye movements during tasks that involve stimulus identification and motor responses following temporal cues.

Anticholinergic activity in the nervous system: Consequences for visuomotor function.

Acetylcholine is present in the peripheral and central nervous system, where it is involved in a number of fundamental physiological and biochemical processes. In particular, interaction with muscarinic receptors can cause adverse effects such as dry mouth, drowsiness, mydriasis and cognitive dysfunction. Despite the knowledge that exists regarding these common side-effects, little is known about how anticholinergic medications influence central motor processes and fine motor control in healthy individuals. This paper reviews critical visuomotor processes that operate in healthy individuals, and how controlling these motor processes are influenced by medications that interfere with central cholinergic neurotransmission. An overview of receptor function and neurotransmitter interaction following the ingestion or administration of anticholinergics is provided, before exploring how visuomotor performance is affected by anticholinergic medications. In particular, this review will focus on the effects that anticholinergic medications have on fixation stability, saccadic eye movements, smooth pursuit eye movements, and general pupil dynamics.