Activation of the HMGB1-RAGE axis upregulates TH expression in dopaminergic neurons via JNK phosphorylation

Sepsis-induced inflammatory demyelination in medullary visceral zone and cholinergic anti-inflammatory pathway: Insights from a Rat's model study

Background

Our previous studies have demonstrated that the activated Cholinergic Anti-inflammatory Pathway (CAP) effectively suppresses systemic inflammation and immunity in early sepsis. Some parameters of Heart Rate Variability (HRV) could be used to reflect the regulatory activity of CAP. However, in the early stages of severe sepsis of some patients, the inflammatory storm can still result in multiple organs dysfunction and even death, suggesting they lose CAP's modulation ability. Since CAP is part of the vagus nerve and is directly innervated by the Medullary Visceral Zone (MVZ), we can reasonably concluded that pathological changes induced by MVZ's neuroinflammation should be responsible for CAP's dysfunction in modulating systemic inflammation in early sepsis.

Methods

We conducted two independent septic experiments, the sepsis model rats were prepared by cecum ligation and puncture (CLP) method. In the first experiment, A total of 64 adult male Sprague-Dawley rats were included. Under the condition of sepsis and CAP's pharmacological activation or blockade, we investigated the MVZ's pathological changes, the functional state of key neurons including catecholaminergic and cholinergic neurons, key genes' expression such as Oligodendrocyte Transcription Factor 2 (Olig-2) mRNA, glial fibrillary acidic protein (GFAP) mRNA, and matrix metalloprotein (MMP) -9 mRNA, and CAP's activities reflected by HRV. The second experiment involved in 56 rats, through central anti-inflammation by feeding with 10 mg/ml minocycline sucrose solution as the only water source, or right vagus transection excepting for central anti-inflammation as a mean of the CAP's functional cancel, we confirmed that the neuroinflammation in MVZ affected systemic inflammation through CAP in sepsis.

Results

In the first experiment, cholinergic and catecholaminergic neurons showed significant apoptosis with reduced expressions of TH, but the expression of CHAT remained relatively unaffected in MVZ in sepsis. HRV parameters representing the tone of the vagus nerve, such as SDNN, RMSSD, HF, SD1, and SD2, did not show significant differences among the three Septic Groups, although they all decreased significantly compared to the Control Group. The expressions of GFAP mRNA and MMP-9 mRNA were up-regulated, while the expression of Olig-2 mRNA was down-regulated in the Septic Groups. Intervention of CAP had a significant effect on cholinergic and catecholaminergic neurons' apoptosis, as well as the expressions of TH/CHAT and these key genes, but had little effect on HRV in sepsis. In the second experiment, the levels of TNF-α, IL-6, in serum and MVZ were significantly increased in sepsis. Central anti-inflammatory treatment reversed these changes. However, right vagotomy abolished the central anti-inflammatory effect.

Conclusions

Our study uncovered that MVZ's neuroinflammation may play a crucial role in the uncontrolled systemic inflammation through inflammatory demyelination in MVZ, which disrupts CAP's modulation on the systemic inflammation in early sepsis.

Activating α7nAChR suppresses systemic inflammation by mitigating neuroinflammation of the medullary visceral zone in sepsis in a rat model

Our previous studies have shown that activating α7nAChRs suppresses systemic inflammation and immunity through the cholinergic anti-inflammatory pathway (CAP) in early sepsis. Now that the medullary visceral zone (MVZ) is the center of CAP and responsible for regulating systemic inflammation, what changes will occur in MVZ's pathology and function in sepsis, especially when interfering with α7nAChRs? Does activation of MVZ's α7nAChRs contribute to the inhibition of systemic inflammation? To clarify these issues, we explored the systemic inflammation and immunity state by detecting serum levels of TNF-α, IL-6, HMGB1, sCD14, and CD4+CD25+Treg and TH17 lymphocytes percentage, meanwhile, we analyzed the apoptosis of cholinergic and catecholaminergic neurons and the expressions of tyrosine hydroxylase (TH) and choline acetyltransferase (CHAT) in MVZ in sepsis and the interfering effects on α7nAChRs. In this study, we found that in sepsis, serum TNF-α, IL-6, HMGB1, sCD14, CD4+CD25+Treg, and TH17 lymphocytes significantly increased and the ratio of Treg/TH17 significantly decreased, cholinergic and catecholaminergic neurons underwent apoptosis with low expressions of TH and CHAT in MVZ; activation of α7nAChRs not only significantly decreased the levels of septic serum TNF-α, IL-6, HMGB1, sCD14, and TH17 lymphocytes (P ＜ 0.05), but also significantly reduced cholinergic and catecholaminergic neurons' apoptosis, and promoted expressions of TH/CHAT. Our study reveals that sepsis undermines MVZ through neuroinflammation which contributes to the uncontrolled systemic inflammation. Activating central α7nAChRs is not only helpful to restore MVZ's structure and function but also beneficial to subside the inflammatory storm in sepsis. Even if MVZ is damaged in sepsis, cholinergic neurons in MVZ still regulate the systemic inflammation stably.

Clinical Manifestation of AGE-RAGE Axis in Neurodegenerative and Cognitive Impairment Disorders

The receptor of Advanced Glycation Endproducts (RAGE) and Advanced Glycation Endproducts (AGE) have multiple functions in our body and their restraint are being observed in neurodegenerative and memory impairment disorders. The review of different pathways allows an understanding of the probable mechanism of neurodegeneration and memory impairment involving RAGE and AGE. Commonly we observe AGE accumulation in neural cells and tissues but the extent of accumulation increases with the presence of memory impairment disorder. The presence of AGEs can also be seen in morbid accumulation, pathological structures in the form of amyloid clots, and nervous fibrillary tangles in Alzheimer's Disease (AD) and memory impairment disease.Many neuropathological and biochemical aspects of AD are explained by AGEs, including widespread protein crosslinking, glial activation of oxidative stress, and neuronal cell death. Oxidative stress is due to different reasons and glycation end products set in motion and form or define various actions which are normally due to AGE changes in a pathogenic cascade. By regulating the transit of ß-amyloid in and out of the brain or altering inflammatory pathways, AGE and it's ensnare receptor such as soluble RAGE may function as blockage or shield AD development. RAGE activates the transcription-controlling factor Necrosis Factor (NF-κB) and increases the protraction of cytokines, like a higher number of Tumor Necrosis Factor (TNF-α) and Interleukin (IL-I) by inducing several signal transduction cascades. Furthermore, binding to RAGE can pro-activate reactive oxygen species (ROS), which is popularly known to cause neuronal death.

Unveiling new secrets in Parkinson's disease: The glycatome

We are witnessing a considerable increase in the incidence of Parkinson's disease (PD), which may be due to the general ageing of the population. While there is a plethora of therapeutic strategies for this disease, they still fail to arrest disease progression as they do not target and prevent the neurodegenerative process. The identification of disease-causing mutations allowed researchers to better dissect the underlying causes of this disease, highlighting, for example, the pathogenic role of alpha-synuclein. However, most PD cases are sporadic, which is making it hard to unveil the major causative mechanisms of this disease. In the recent years, epidemiological evidence suggest that type-2 diabetes mellitus (T2DM) individuals have higher risk and worst outcomes of PD, allowing to raise the hypothesis that some dysregulated processes in T2DM may contribute or even trigger the neurodegenerative process in PD. One major consequence of T2DM is the unprogrammed reaction between sugars, increased in T2DM, and proteins, a reaction named glycation. Pre-clinical reports show that alpha-synuclein is a target of glycation, and glycation potentiates its pathogenicity which contributes for the neurodegenerative process. Moreover, it triggers, anticipates, or aggravates several PD-like motor and non-motor complications. A given profile of proteins are differently glycated in diseased conditions, altering the brain proteome and leading to brain dysfunction and neurodegeneration. Herein we coin the term Glycatome as the profile of glycated proteins. In this review we report on the mechanisms underlying the association between T2DM and PD, with particular focus on the impact of protein glycation.

HMGB1 is a Potential and Challenging Therapeutic Target for Parkinson's Disease

Parkinson's disease (PD) is one of the most common degenerative diseases of the human nervous system and has a wide range of serious impacts on human health and quality of life. Recently, research targeting high mobility group box 1 (HMGB1) in PD has emerged, and a variety of laboratory methods for inhibiting HMGB1 have achieved good results to a certain extent. However, given that HMGB1 undergoes a variety of intracellular modifications and three different forms of extracellular redox, the possible roles of these forms in PD are likely to be different. General inhibition of all forms of HMGB1 is obviously not ideal and has become one of the biggest obstacles in the clinical application of targeting HMGB1. In this review, pure mechanistic research of HMGB1 and in vivo research targeting HMGB1 were combined, the effects of HMGB1 on neurons and immune cell responses in PD are discussed in detail, and the problems that need to be focused on in the future are addressed.

Anti-high-mobility group box-1 (HMGB1) mediates the apoptosis of alveolar epithelial cells (AEC) by receptor of advanced glycation end-products (RAGE)/c-Jun N-terminal kinase (JNK) pathway in the rats of crush injuries

Objectives

The lung injury is often secondary to severe trauma. In the model of crush syndrome, there may be secondary lung injury. We hypothesize that high-mobility group box 1 (HMGB1), released from muscle tissue, mediates the apoptosis of alveolar epithelial cells (AEC) via HMGB1/Receptor of advanced glycation end-products (RAGE)/c-Jun N-terminal kinase (JNK) pathway. The study aimed to investigate how HMGB1 mediated the apoptosis of AEC in the rat model.

Methods

Seventy-five SD male rats were randomly divided into five groups: CS, CS + vehicle, CS + Ethyl pyruvate (EP), CS + FPS-ZM1 group, and CS + SP600125 groups. When the rats CS model were completed after 24 h, the rats were sacrificed. We collected the serum and the whole lung tissues. Inflammatory cytokines were measured in serum samples. Western blot and RT-qPCR were used to quantify the protein and mRNA. Lastly, apoptotic cells were detected by TUNEL. We used SPSS 25.0 for statistical analyses.

Results

Nine rats died during the experiments. Dead rats were excluded from further analysis. Compared to the CS group, levels of HMGB1 and inflammatory cytokines in serum were downregulated in CS + EP, CS + FPS-ZM1, and CS + SP600125 groups. Western blot and RT-qPCR analysis revealed a significant downregulation of HMGB1, RAGE, and phosphorylated-JNK in CS + EP, CS + FPS-ZM1, and CS + SP600125 groups, compared with the CS groups, excluding total-JNK mRNA. Apoptosis of AEC was used TUNEL to assess. We found the TUNEL-positive cells were downregulated in CS + EP, CS + FPS-ZM1, and CS + SP600125 groups.

Conclusion

The remote lung injury begins early after crush injuries. The HMGB1/RAGE/JNK signaling axis is an attractive target to abrogate the apoptosis of AEC after crush injuries.

The Regulation Effect of α7nAChRs and M1AChRs on Inflammation and Immunity in Sepsis

The inflammatory storm in the early stage and immunosuppression in the late stage are responsible for the high mortality rates and multiple organ dysfunction in sepsis. In recent years, studies have found that the body's cholinergic system can spontaneously and dynamically regulate inflammation and immunity in sepsis according to the needs of the body. Firstly, the vagus nerve senses and regulates local or systemic inflammation by means of the Cholinergic Anti-inflammatory Pathway (CAP) and activation of α7-nicotinic acetylcholine receptors (α7nAChRs); thus, α7nAChRs play important roles for the central nervous system (CNS) to modulate peripheral inflammation; secondly, the activation of muscarinic acetylcholine receptors 1 (M1AChRs) in the forebrain can affect the neurons of the Medullary Visceral Zone (MVZ), the core of CAP, to regulate systemic inflammation and immunity. Based on the critical role of these two cholinergic receptor systems in sepsis, it is necessary to collect and analyze the related findings in recent years to provide ideas for further research studies and clinical applications. By consulting the related literature, we draw some conclusions: MVZ is the primary center for the nervous system to regulate inflammation and immunity. It coordinates not only the sympathetic system and vagus system but also the autonomic nervous system and neuroendocrine system to regulate inflammation and immunity; α7nAChRs are widely expressed in immune cells, neurons, and muscle cells; the activation of α7nAChRs can suppress local and systemic inflammation; the expression of α7nAChRs represents the acute or chronic inflammatory state to a certain extent; M1AChRs are mainly expressed in the advanced centers of the brain and regulate systemic inflammation; neuroinflammation of the MVZ, hypothalamus, and forebrain induced by sepsis not only leads to their dysfunctions but also underlies the regulatory dysfunction on systemic inflammation and immunity. Correcting the neuroinflammation of these regulatory centers and adjusting the function of α7nAChRs and M1AChRs may be two key strategies for the treatment of sepsis in the future.

Electroacupuncture Alleviates Neuroinflammation and Motor Dysfunction by Regulating Intestinal Barrier Function in a Mouse Model of Parkinson Disease

Gastrointestinal dysfunction is the main nonmotor characteristic of Parkinson disease (PD), manipulation of gastrointestinal function by altering gut-brain axis is a potentially novel entry point for the treatment of PD. Acupuncture has been reported to confer beneficial effects in the gastrointestinal diseases. Therefore, this study aimed to explore the effects and mechanism of acupuncture on the pathophysiology and gastrointestinal function of PD. A PD mouse model was established by rotenone, and electroacupuncture was used to regulate the gastrointestinal function. Rotenone was found to induce the types of brain pathologies and gastrointestinal dysfunction that are similar to those observed with PD. Electroacupuncture significantly increased the spontaneous activity of mice with PD and increased the expression of tyrosine hydroxylase, while reducing the expression of Iba-1 in substantia nigra (SN), suggesting that motor dysfunction and neurological damage was alleviated. In addition, electroacupuncture significantly reduced the deposition of α-synuclein in both colon and SN, reduced intestinal inflammation, and exerted protective effects on enteric nervous system and intestinal barrier. In conclusion, electroacupuncture confers beneficial effects on the gastrointestinal system of mice with PD and can alleviate neuroinflammation and neuropathic injury by inhibiting intestinal inflammation, promoting intestinal barrier repair and reducing α-synuclein deposition in the colon.

Neuroprotective effects of short-chain fatty acids in MPTP induced mice model of Parkinson's disease

Gut microbial metabolites, SCFAs, were related with the occurrence and development of Parkinson's disease (PD). But the effects of different short-chain fatty acids (SCFAs) on PD and involving mechanisms are still undefined. In this study we evaluate the effects of three dominant SCFAs (acetate, propionate and butyrate) on motor damage, dopaminergic neuronal degeneration and underlying neuroinflammation related mechanisms in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced PD mice. High (2.0 g/kg) or low doses (0.2 g/kg) of sodium acetate (NaA), sodium propionate (NaP) or sodium butyrate (NaB) were gavaged into PD mice for 6 weeks. High doses of NaA reduced the turning time of PD mice. NaB significantly reduced the turning and total time in pole test, and increased the average velocity in open field test when compared with PD mice, indicating the most effective alleviation of PD-induced motor disorder. Low and high doses of NaB significantly increased the content of tyrosine hydroxylase (TH) by 12.3% and 20.2%, while reduced α-synuclein activation by 159.4% and 132.7% in the substantia nigra pars compacta (SNpc), compared with PD groups. Butyrate reached into the midbrain SNpc and suppressed microglia over-activation. It inhibited the levels of pro-inflammatory factors (IL-6, IL-1β and TNF-α) (P < 0.01) and iNOS. Besides, butyrate inhibited the activation of NF-κB and MAPK signaling pathways in the SNpc region. Consequently, sodium butyrate could inhibit neuroinflammation and alleviate neurological damage of PD.

Alarmins and c-Jun N-Terminal Kinase (JNK) Signaling in Neuroinflammation

Neuroinflammation is involved in the progression or secondary injury of multiple brain conditions, including stroke and neurodegenerative diseases. Alarmins, also known as damage-associated molecular patterns, are released in the presence of neuroinflammation and in the acute phase of ischemia. Defensins, cathelicidin, high-mobility group box protein 1, S100 proteins, heat shock proteins, nucleic acids, histones, nucleosomes, and monosodium urate microcrystals are thought to be alarmins. They are released from damaged or dying cells and activate the innate immune system by interacting with pattern recognition receptors. Being principal sterile inflammation triggering agents, alarmins are considered biomarkers and therapeutic targets. They are recognized by host cells and prime the innate immune system toward cell death and distress. In stroke, alarmins act as mediators initiating the inflammatory response after the release from the cellular components of the infarct core and penumbra. Increased c-Jun N-terminal kinase (JNK) phosphorylation may be involved in the mechanism of stress-induced release of alarmins. Putative crosstalk between the alarmin-associated pathways and JNK signaling seems to be inherently interwoven. This review outlines the role of alarmins/JNK-signaling in cerebral neurovascular inflammation and summarizes the complex response of cells to alarmins. Emerging anti-JNK and anti-alarmin drug treatment strategies are discussed.

Exploring the Mechanism on the Medullary Visceral Zone Inhibiting the Cholinergic Anti-inflammatory Pathway Induced by Sepsis

Inflammatory storm is an important pathological mechanism of multiple organ dysfunction, and it is associated with most deaths in septic patients, deserving to be studied. Recent findings have confirmed that the Medullary Visceral Zone (MVZ) regulates inflammation and immunity through the cholinergic anti-inflammatory pathway (CAP), but how sepsis affects the MVZ and leads to uncontrolled inflammation remain unclear. The current study reported that sepsis induced MVZ to inhibit CAP which underlies the inflammation storm. Our studies have shown that the rat models of sepsis prepared by cecal ligation and puncture had a higher inflammatory level, higher mortality, and higher Murine Sepsis Score. In septic rats, some indicators of heart rate variability (HRV) such as SDNN, HF band, RMSSD, SD1, and SD2 significantly reduced. In MVZ of septic rats, many cholinergic and catecholaminergic neurons showed apoptotic, with low expressions of tyrosine hydroxylase and choline acetyltransferase. The α7nAChR agonist GTS-21 can improve these pathologies, while the α7nAChR antagonist MLA is the opposite. Our study demonstrates for the first time that cholinergic and catecholaminergic neurons in MVZ went through significant apoptosis and inactiveness in sepsis, which contributes to the inhibition of CAP and acceleration of the inflammation storm in early sepsis. Intervening with CAP has a significant effect on the activity and apoptosis of MVZ neurons while altering systemic inflammation and immunity; in addition, for the first time, we confirmed that some indicators of HRV such as SDNN, HF band, RMSSD, SD1, and SD2 can reflect the activity of CAP, but the CAP interference had little effect on these indicators.

Non-cell autonomous modulation of tyrosine hydroxylase by HMGB1 released from astrocytes in an acute MPTP-induced Parkinsonian mouse model

High-mobility group box 1 (HMGB1) is actively secreted from inflammatory cells and acts via a non-cell-autonomous mechanism to play an important role in mediating cell proliferation and migration. The HMGB1-RAGE (receptor for advanced glycation end products) axis upregulates tyrosine hydroxylase (TH) expression in response to extracellular insults in dopaminergic neurons in vitro, but little is known about HMGB1 in modulation of dopaminergic neurons in vivo. Here, using immunohistochemistry, we show that HMGB1 and RAGE expression are higher in the nigral area of MPTP (methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-treated mice, a toxin-induced Parkinsonian mouse model, compared with saline-treated controls. HMGB1 was predominantly localized to astrocytes and may affect neighboring dopaminergic neurons in the MPTP mouse model, owing to co-localization of RAGE in these TH-positive cells. In addition, MPTP induced a decrease in TH expression, an effect that was potentiated by inhibition of c-Jun N-terminal kinase (JNK) or RAGE. Moreover, stereotaxic injection of recombinant HMGB1 attenuated the MPTP-induced reduction of TH in a Parkinsonian mouse model. Collectively, our results suggest that an increase of HMGB1, released from astrocytes, upregulates TH expression in an acute MPTP-induced Parkinsonian mouse model, thereby maintaining dopaminergic neuronal functions.

Chloramphenicol Mitigates Oxidative Stress by Inhibiting Translation of Mitochondrial Complex I in Dopaminergic Neurons of Toxin-Induced Parkinson's Disease Model

Paraquat (PQ), an herbicide considered an environmental contributor to the development of Parkinson's disease (PD), induces dopaminergic neuronal loss through reactive oxygen species (ROS) production and oxidative stress by mitochondrial complex I. Most patients with PQ-induced PD are affected by chronic exposure and require a preventive strategy for modulation of disease progression. To identify drugs that are effective in preventing PD, we screened more than 1000 drugs that are currently used in clinics and in studies employing PQ-treated cells. Of these, chloramphenicol (CP) showed the most powerful inhibitory effect. Pretreatment with CP increased the viability of PQ-treated SN4741 dopaminergic neuronal cells and rat primary cultured dopaminergic neurons compared with control cells treated with PQ only. CP pretreatment also reduced PQ-induced ROS production, implying that mitochondrial complex I is a target of CP. This effect of CP reflected downregulation of the mitochondrial complex I subunit ND1 and diminished PQ recycling, a major mechanism of ROS production, and resulted in the prevention of cell loss. Notably, these effects of CP were not observed in rotenone-pretreated SN4741 cells and Rho-negative cells, in which mitochondrial function is defective. Consistent with these results, CP pretreatment of MPTP-treated PD model mice also ameliorated dopaminergic neuronal cell loss. Our findings indicate that the inhibition of mitochondrial complex I with CP protects dopaminergic neurons and may provide a strategy for preventing neurotoxin-induced PD.

Role of Mitogen Activated Protein Kinase Signaling in Parkinson's Disease

Parkinson's disease (PD) is a neurodegenerative disorder caused by insufficient dopamine production due to the loss of 50% to 70% of dopaminergic neurons. A shortage of dopamine, which is predominantly produced by the dopaminergic neurons within the substantia nigra, causes clinical symptoms such as reduction of muscle mass, impaired body balance, akinesia, bradykinesia, tremors, postural instability, etc. Lastly, this can lead to a total loss of physical movement and death. Since no cure for PD has been developed up to now, researchers using cell cultures and animal models focus their work on searching for potential therapeutic targets in order to develop effective treatments. In recent years, genetic studies have prominently advocated for the role of improper protein phosphorylation caused by a dysfunction in kinases and/or phosphatases as an important player in progression and pathogenesis of PD. Thus, in this review, we focus on the role of selected MAP kinases such as JNKs, ERK1/2, and p38 MAP kinases in PD pathology.

Synergistic Inhibition of ERK1/2 and JNK, Not p38, Phosphorylation Ameliorates Neuronal Damages After Traumatic Brain Injury

Mitogen-activated protein (MAP) kinases are serine/threonine protein kinases that play a critical role in signal transduction and are activated by phosphorylation in response to a variety of pathophysiology stimuli. While MAP kinase signaling has a significant role in the pathophysiology of several neurodegenerative diseases, the precise function of activation of MAP kinase in traumatic brain injury (TBI) is unknown. Therefore, it is important to study the role of MAP kinase signaling in TBI-associated neurological ailments. In this study, using an in vitro stretch injury model in rat embryo neuronal cultures and the in vivo fluid percussion injury (FPI) model in rats, we explored the role of MAP kinase signaling in the mechanisms of cell death in TBI. Our study demonstrated that the stretch injury in vitro and FPI in vivo upregulated the phosphorylation of MAP kinase proteins ERK1/2 and JNK, but not p38. Using ERK1/2 inhibitor U0126, JNK inhibitor SP600125, and p38 inhibitor SB203580, we validated the role of MAP kinase proteins in the activation of NF-kB and caspase-3. By immunofluorescence and western blotting, further, we demonstrated the role of ERK1/2 and JNK phosphorylation in neurodegeneration by analyzing cell death proteins annexin V and Poly-ADP-Ribose-Polymerase p85. Interestingly, combined use of ERK1/2 and JNK inhibitors further attenuated the cell death in stretch-injured neurons. In conclusion, this study could establish the significance of MAP kinase signaling in the pathophysiology of TBI and may have significant implications for developing therapeutic strategies using ERK1/2 and JNK inhibitors for TBI-associated neurological complications.

A C. elegans Model for the Study of RAGE-Related Neurodegeneration

The receptor for advanced glycation products (RAGE) is a cell surface, multi-ligand receptor belonging to the immunoglobulin superfamily; this receptor is implicated in a variety of maladies, via inflammatory pathways and induction of oxidative stress. Currently, RAGE is being studied using a limited number of mammalian in vivo, and some complementary in vitro, models. Here, we present a Caenorhabditis elegans model for the study of RAGE-related pathology: a transgenic strain, expressing RAGE in all neurons, was generated and subsequently tested behaviorally, developmentally, and morphologically. In addition to RAGE expression being associated with a significantly shorter lifespan, the following behavioral observations were made when RAGE-expressing worms were compared to the wild type: RAGE-expressing worms showed an impaired dopaminergic system, evaluated by measuring the fluorescent signal of GFP tagging; these worms exhibited decreased locomotion-both general and following ethanol exposure-as measured by counting body bends in adult worms; RAGE expression was also associated with impaired recovery of quiescence and pharyngeal pumping secondary to heat shock, as a significantly smaller fraction of RAGE-expressing worms engaged in these behaviors in the 2 h immediately following the heat shock. Finally, significant developmental differences were also found between the two strains: RAGE expression leads to a significantly smaller fraction of hatched eggs 24 h after laying and also to a significantly slower developmental speed overall. As evidence for the role of RAGE in a variety of neuropathologies accumulates, the use of this novel and expedient model should facilitate the elucidation of relevant underlying mechanisms and also the development of efficient therapeutic strategies.