Pathology of pain and its implications for therapeutic interventions

Knowledge and attitudes toward pediatric pain management among final-year medical students in Italy: a multicenter observational study

Pain management in pediatric patients is a critical aspect of healthcare, yet there is limited research on the knowledge and approaches of medical students regarding this topic. This study investigates the approach to pediatric pain management among final-year medical students. A cross-sectional survey was administered to final-year medical students from six universities located in Northern, Central, and Southern Italy between May and July 2024. The questionnaire (16 items) assessed the students' knowledge and attitudes toward acute pain management in pediatric patients. Descriptive and inferential statistics were used to analyze the data. A total of 321 students completed the survey. The majority (49%) of students reported limited training (< 1 h) in pediatric pain management during their studies. Only 42% of respondents believed that neonates feel pain more intensively than adults, while 38% thought the same for children up to 3 years. old While 81% recognized that pediatric pain can be measured with age-specific tools, 60% would avoid using opioids for severe pain in children. Seventy-five percent of students reported routinely using analgesia before painful procedures, but 33% would not treat abdominal pain before surgical evaluation in a suspected appendicitis case. Conclusion: There are relevant gaps in the education of medical students on pediatric pain management in Italy. Traditional old views on pain are widespread among final-year medical students. Targeted educational interventions are needed to address these issues and ensure that future healthcare providers are adequately prepared to manage pediatric pain. What is Known • Pediatric pain is often undertreated due to misconceptions among healthcare providers about their pain perception and the long-term consequences of untreated pain. • Studies investigating knowledge and attitudes toward pediatric pain management have primarily focused on physicians or nurses, with limited evidence on medical students' preparation in this area. What is New • This study reveals significant gaps in knowledge and outdated attitudes toward pediatric pain management among final-year medical students in Italy • Barriers to the use of opioids for severe pain management in children are already widespread among medical students.

The Role of TNF-α in Neuropathic Pain: An Immunotherapeutic Perspective

TNF-α is a pro-inflammatory cytokine that plays a pivotal role in the regulation of immune responses. It is predominantly produced by activated macrophages, although other cell types, such as T lymphocytes and NK cells, also contribute to its secretion. TNF-α participates in various physiological processes, including cell proliferation and differentiation. Moreover, TNF-α has been implicated in the pathogenesis of numerous inflammatory and autoimmune disorders. Recent studies have highlighted the important role of TNF-α in neuropathic pain, a complex and frequently disabling condition caused by nerve injury or dysfunction. Increased TNF-α levels in the nervous system have been associated with the onset of neuropathic pain, contributing to neuronal sensitization and alterations in pain signaling pathways. This study supports the idea that TNF-α connects the immune system with the nervous system, thereby supporting our understanding of the neuroimmune interface of pain and bringing a potential treatment against neuropathic pain: targeting TNF-α. Anti-TNF-α antibody administration reduces pain behaviors and neuroinflammation in preclinical animal models. Simultaneously, clinical trials are evaluating the safety and efficacy of anti-TNF-α treatments, with preliminary results indicating promising outcomes in patients experiencing neuropathic pain. Here, targeting TNF-α goes beyond its conventional spectrum of inflammatory pathologies and initiates a new mechanism-based approach to defining neuropathic pain, thereby improving the quality of life of the individuals affected and bringing together an area of colossal unmet clinical need.

Repetitive transcranial magnetic stimulation ameliorates chronic pain behavior and modulates the brain transcriptome in a mouse model of chronic constriction injury

BACKGROUND AND AIM

Neuropathic pain (NP), caused by nerve injury or dysfunction, poses a significant clinical challenge due to its limited response to conventional pharmacological treatments. Repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising non-invasive neuromodulatory approach for NP management. This study aimed to evaluate the therapeutic efficacy of rTMS in alleviating NP induced by chronic constriction injury (CCI) in a mouse model and to investigate the underlying molecular mechanisms through transcriptomic profiling.

PROCEDURES

Adult male mice underwent CCI surgery to induce NP and were randomly assigned to receive either rTMS (5 Hz or 10 Hz) or sham stimulation. rTMS was applied once daily for 14 consecutive days, beginning on postoperative day 7. Behavioral assessments-including paw withdrawal latency (PWL) and paw withdrawal threshold (PWT)-were conducted to evaluate thermal hyperalgesia and mechanical allodynia, respectively. Anxiety-like behaviors were assessed using the open field test (OFT) and elevated plus maze (EPM). At the end of the treatment period, brain tissues were harvested for RNA sequencing and differentially expressed genes (DEGs) were identified and analyzed.

RESULTS AND CONCLUSION

rTMS at both 5 Hz and 10 Hz significantly improved PWL and PWT in CCI mice and reduced anxiety-like behaviors. Transcriptomic analysis revealed that CCI induced dysregulation of 66 genes, while rTMS partially normalized gene expression patterns. Functional enrichment analysis indicated significant involvement of pathways related to inflammatory responses, transporter activity, and ion channel regulation. These findings support the potential of rTMS as a multifaceted, non-invasive therapeutic strategy for neuropathic pain, with molecular mechanisms likely involving modulation of neuroinflammatory and neuroexcitatory pathways.

The anti-nociceptive and anti-inflammatory effects of Pelargonium graveolens essential oil nanoemulsion in mice

Pain and inflammation are the severe problems of the world. Essential oils (EOs) have been considered for treating pain and inflammation. As EOs are unstable and insoluble in water, nanoemulsions can improve bioavailability and efficacy. This study formulated Pelargonium graveolens essential oil nanoemulsion (PGEO-NE) using Tween 80 as a carrier. The activity of PGEO-NE (50 and 100 mg/kg) and the involvement of the opioid pathway were investigated in different models of nociception and inflammation in mice. The droplets in PGEO-NE are spherical, with a particle size of around 553 nm and a polydispersity index of 0.113. GC/MS analysis of PGEO revealed citronellol (34.9%), geraniol (16.1%), citronellyl formate (12.3%), and linalool (6.8%) as the main constituents. PGEO-NE significantly reduced the duration of formalin-induced paw licking/biting in both phases and the number of acetic acid-induced writhings, and increased the hot plate latency, compared to vehicle and PGEO (10 mg/kg), equivalent to the PGEO-NE dose of 100 mg/kg. The anti-nociceptive potential of PGEO-NE (100 mg/kg) in the hot plate and acetic acid tests was reversed by the opioid antagonist. After formalin and carrageenan injections, PGEO-NE significantly inhibited paw edema, but PGEO (10 mg/kg) had no effect. These results confirm that PGEO-NE inhibits pain and inflammation via the opioid pathway.

Genetic determinants of paclitaxel-induced peripheral neuropathy: a review of current literature

Paclitaxel is a widely used chemotherapeutic agent recognized for its efficacy against various malignancies. However, its clinical utility is often limited by paclitaxel-induced peripheral neuropathy (PIPN), a dose-dependent and debilitating side effect that significantly impacts patient quality of life. Genetic predisposition plays a critical role in individual susceptibility to PIPN, influencing both drug metabolism and neuropathic responses. This review examines the genetic basis of PIPN, focusing on polymorphisms in key genes associated with paclitaxel metabolism, transport, neuroinflammation, and neuronal signaling. Variants in CYP2C8, CYP3A4, and CYP2C9 affect drug metabolism, while polymorphisms in ABCB1 and SLCO1B1 influence drug transport. Genes involved in neuroinflammatory pathways (TNF-α, IL-6, IL-1β), peripheral nerve integrity (MAPT, TUBB2), and neuronal signaling (SCN9A) have also been implicated in PIPN susceptibility. Understanding genetic contributions to PIPN is essential for unraveling its pathophysiology and developing targeted interventions. Integrating genetic markers into clinical practice can facilitate personalized treatment strategies, minimizing PIPN risk and enhancing therapeutic outcomes. Further studies are needed to validate these findings across diverse populations and uncover novel genetic determinants.

Neuro-Nutritional Approach to Neuropathic Pain Management: A Critical Review

Pain is a significant global public health issue that can interfere with daily activities, sleep, and interpersonal relationships when it becomes chronic or worsens, ultimately impairing quality of life. Despite ongoing efforts, the efficacy of pain treatments in improving outcomes for patients remains limited. At present, the challenge lies in developing a personalized care and management plan that helps to maintain patient activity levels and effectively manages pain. Neuropathic pain is a chronic condition resulting from damage to the somatosensory nervous system, significantly impacting quality of life. It is partly thought to be caused by inflammation and oxidative stress, and clinical research has suggested a link between this condition and diet. However, these links are not yet well understood and require further investigation to evaluate the pathways involved in neuropathic pain. Specifically, the question remains whether supplementation with dietary antioxidants, such as melatonin, could serve as a potential adjunctive treatment for neuropathic pain modulation. Melatonin, primarily secreted by the pineal gland but also produced by other systems such as the digestive system, is known for its anti-inflammatory, antioxidant, and anti-aging properties. It is found in various fruits and vegetables, and its presence alongside other polyphenols in these foods may enhance melatonin intake and contribute to improved health. The aim of this review is to provide an overview of neuropathic pain and examine the potential role of melatonin as an adjunctive treatment in a neuro-nutritional approach to pain management.

Estrogen-Mediated Neural Mechanisms of Sex Differences in Burning Mouth Syndrome

BACKGROUND/OBJECTIVES

Burning mouth syndrome (BMS) is a chronic pain disorder of the oral cavity in the absence of organic disease and is prevalent among menopausal women. Estrogen may be involved in the formation of nerves involved in pain.

METHODS

This paper presents an inferred mechanism for the relationship between estrogen and BMS based on a synthesis and interpretation of findings from a selection of published studies.

RESULTS

Estrogen influences the formation of neural circuits in BMS by dividing the complex pain circuit into the following three components: the peripheral pain circuit, brain network pain circuit, and memorized pain circuit.

CONCLUSIONS

The development of BMS may be influenced by the formation of neural circuits by sex hormones.

Unveiling the hidden pain and daily struggles of individuals with a venous leg ulcer: a thematic analysis

AIM

This study aimed to explore the experiences of pain among individuals living with venous leg ulcers (VLUs), focusing on how pain was described, its impact on daily living, and the coping strategies employed by them.

MATERIALS AND METHODS

A secondary qualitative analysis was conducted using data from a previous study on VLU self-management following nurse-led patient education. The original study employed a constructivist grounded theory approach, while this secondary analysis utilized Braun and Clarke's thematic analysis methodology. Semi-structured interviews from 22 participants were analyzed to identify emergent themes related to pain. MAXQDA® software was used to ensure traceability of coding, and rigor was ensured through triangulation and reflexive memos.

RESULTS

Three themes emerged: (1) Description of Wound-Related Pain where participants described pain as persistent, multifaceted, and often excruciating, using terms such as "burning" and "stinging." Pain intensity varied across individuals, with some comparing it to childbirth. (2) Impact on Daily Living where pain considerably affected emotional well-being, mobility, social interactions, and sleep. Many participants experienced emotional exhaustion, frustration, and social isolation due to their condition. (3) Pain Management Strategies where participants used both pharmacological (e.g., paracetamol, tramadol) and non-pharmacological methods (e.g., leg elevation, self-hypnosis) for pain relief. The role of healthcare providers was essential, though some participants felt their pain was inadequately addressed.

CONCLUSION

VLU-associated pain is a prevalent and debilitating aspect of individuals' lives, impacting both physical and psychological health. Comprehensive pain management strategies that integrate both pharmacological and psychosocial approaches should be enhanced to improve patient outcomes.

Pain Signaling by GPCRs and RTKs

Chronic pain is common and debilitating, yet is inadequately treated by current therapies, which can have life-threatening side effects. Treatments targeting G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs), key pain mediators, often fail in clinical trials for unknown reasons. Here, we discuss the recent evidence that GPCRs and RTKs generate sustained signals from multiprotein signaling complexes or signalosomes in intracellular compartments to control chronic pain. We evaluate the evidence that selective antagonism of these intracellular signals provides more efficacious and long-lasting pain relief than antagonism of receptors at the surface of cells. We highlight how the identification of coreceptors and molecular scaffolds that underpin pain signaling by multiple receptors has identified new therapeutic targets for chronic pain, surmounting the redundancy of the pain signaling pathway.

Metformin as a disease-modifying therapy in osteoarthritis: bridging metabolism and joint health

Background

Osteoarthritis (OA) and impaired glucose tolerance (IGT) frequently coexist, leading to compounded clinical and metabolic challenges. This study investigates the effects of metformin in improving both clinical outcomes (pain, stiffness, physical function) and metabolic parameters (inflammatory markers, lipid profile, BMI) in patients with knee OA and IGT.

Methods

The study included 60 patients diagnosed with knee OA and IGT. Participants were divided into two groups: 26 patients received standard OA treatment without metformin (Without Metf), while 34 received metformin (500 mg twice daily) for 3 months, in addition to standard treatment (With Metf). Clinical assessments (WOMAC, Lequesne Algofunctional Index, KOOS, VAS) and metabolic markers (CRP, NLR, SOD, lipid profile, BMI) were measured before treatment, after 1 month, and after 3 months.

Results

The With Metf group showed significantly greater improvements in pain, stiffness, physical function, and quality of life compared to the Without Metf group. Metformin also led to significant reductions in inflammatory markers and improvements in lipid profiles and metabolic health indicators. The With Metf group demonstrated enhanced BMI, waist-to-hip ratio, and waist-to-height ratio. Furthermore, the need for increased NSAID doses was predicted by factors such as pain severity and inflammatory markers.

Conclusion

Metformin effectively alleviates osteoarthritis symptoms and improves metabolic health in patients with both OA and IGT. Further research is needed to explore its long-term effects on joint health, inflammatory markers, and its potential role in OA management in patients without IGT.

Decreased anxiety-like behavior and trigeminal ganglion BDNF levels persist in rats with temporomandibular joint arthritis even after resolution of the nociceptive process

In this study, pain- and anxiety-like behaviors, locomotor and exploratory activity, histological and biomarker parameters were evaluated following induction of a temporomandibular joint (TMJ) arthritis model in rats. Twenty-two adult male Wistar rats were assigned to receive either saline (sham group) or Complete Freund's Adjuvant (CFA - pain group) into the right TMJ. Mechanical allodynia was assessed using the facial electronic von Frey (VF) test, while thermal hyperalgesia was assessed using the Orofacial Pain Assessment Device (OPAD) assay. Open-field and plus-maze tests were used to assess locomotor and exploratory activity and anxiety-like behaviors, respectively. BDNF, IL-1β, and IL-10 levels were analyzed by ELISA in both the ipsilateral and contralateral trigeminal ganglion (TG). The tissues adjacent to the TMJ were histologically evaluated for the inflammatory process. According to distribution, data were analyzed by GEE, independent t-test, or Mann-Whitney test. Significance was set at P < 0.05. On the ninth day following CFA injection, pain-rats presented mechanical allodynia, which persisted until the twenty-first day, a decrease in the number of OPAD licks, decreased BDNF levels in the contralateral TG, and an increase in the ipsilateral TG BDNF and IL-1β levels, with inflammatory infiltrates in the tissues adjacent to the TMJ (27 days). TMJ arthritis also resulted in a reduction of the anxiety index (AI) after 26 days. This study reveals that this model is effective for examining chronic alterations related to TMJ arthritis and for identifying new anti-inflammatory drugs for pain management.

The connection between endometriosis and secondary dysmenorrhea

Endometriosis (EMS) is a prevalent gynecological condition characterized by the presence of endometrial tissue outside the uterus, often leading to secondary dysmenorrhea (SD), chronic pelvic pain and infertility. This review explores the intricate connection between EMS- associated pain and SD, focusing on the pathophysiological mechanisms underlying dysmenorrhea in EMS. Key contributors to pain include inflammation, aberrant immune responses, neurogenic inflammation, peritoneal irritation, peripheral sensitization, central sensitization and cross-organ sensitization. Understanding the pain pathways in EMS highlights the complexity of symptom manifestation and underscores the necessity for a multidisciplinary approach to management. Clinical manifestations, including chronic pelvic pain, dyspareunia, infertility, gastrointestinal and bladder symptoms, fatigue and malaise, are discussed, emphasizing the diverse impact of EMS on women's health. Various treatment modalities, ranging from pharmacological interventions to surgical and complementary approaches, are outlined to provide comprehensive management strategies for EMS-related menstrual pain/SD. This review aims to enhance understanding and facilitate the effective management of EMS-associated SD, ultimately improving the quality of life for affected individuals.

Mixtures of Diethyl Azelate as Novel Nonopioid Modalities for Pain Management

Introduction Effective pain management is essential for improving the quality of life. Currently, we have medications to address both mild and severe pain, but there remains a therapeutic gap for pain that is not adequately managed by over-the-counter (OTC) or prescription non-steroidal anti-inflammatory drugs (NSAIDs). Prescription opioids can lead to addiction, respiratory suppression, and even death. OTC pain relief options often lack the potency required to alleviate more intense pain, while stronger treatments, though effective, carry risks of addiction and other adverse effects, limiting their long-term use. This situation underscores the urgent need for safer, nonopiate alternatives. Both musculoskeletal pain and pain from animal toxin envenomation share common mechanisms, including structural changes to the plasma membrane that trigger signaling cascades from membrane-associated phospholipases. Diethyl azelate (DEA), a medium-chain fatty acid ester, represents a new class of NSAIDs that reversibly alter plasma membrane structure and function. DEA mitigates insulin resistance, dyslipidemia, and musculoskeletal pain, and inhibits both exogenous and endogenous phospholipases PLD and PLA2, which are involved in pain signaling. This study aimed to evaluate the analgesic properties of DEA in combination with topical penetration enhancers. Methodology Analgesic activities of DEA, dimethyl sulfoxide (DMSO), turpentine, 32 miscellaneous terpenes (including D-limonene, menthol, a and b-pinene), cannabinoid oil, pelargonic acid vanillylamide, and non-prescription analgesics drug controls were examined as single entities and in mixtures in cutaneous mechanical sensitivity (CMS) assays that utilized standardized Von Frey monofilaments (fibers) of variable forces. In addition, DEA, DMSO, and D-limonene were tested as single reagents and mixtures in hemolysis assay in vitro. Inhibition of hemolysis was used as a surrogate endpoint for PLA2 enzymatic activity in bee venom. Results Mixtures of DEA and DMSO showed synergy that was most pronounced at equimolar ratios of the components. The maximum duration of sensitivity suppression in CMS assay of 72 h was achieved at 78% DEA and 22% DMSO. Multi-component mixtures of DEA, DMSO, limonene, a-pinene (but not b-pinene), and menthol demonstrated additional enhancement of synergy with DEA at a relatively narrow range of concentrations. Both DMSO and limonene showed bell-shaped dose responses, suggesting that the enhancement of the effects of DEA is not merely due to enhancement of tissue penetration. The activities of multi-component mixtures suggested competition between individual components in certain concentration ranges. The synergy of DEA in mixtures with DMSO and limonene in CMS assays was not observed with related diesters of azelaic acid, diethyl suberate, and diethyl sebacate. In hemolytic assays, DEA, DMSO, and limonene were ineffective as single agents at the examined concentrations, but a specific mixture thereof significantly suppressed hemolysis caused by PLA2. Conclusion The findings warrant further development of the mixtures of DEA, DMSO, and select terpenes as novel modalities.

Unveiling the Mechanisms of Pain in Endometriosis: Comprehensive Analysis of Inflammatory Sensitization and Therapeutic Potential

Endometriosis is a complicated, estrogen-dependent gynecological condition with a high morbidity rate. Pain, as the most common clinical symptom of endometriosis, severely affects women's physical and mental health and exacerbates socioeconomic burden. However, the specific mechanisms behind the occurrence of endometriosis-related pain remain unclear. It is currently believed that the occurrence of endometriosis pain is related to various factors, such as immune abnormalities, endocrine disorders, the brain-gut axis, angiogenesis, and mechanical stimulation. These factors induce systemic chronic inflammation, which stimulates the nerves and subsequently alters neural plasticity, leading to nociceptive sensitization and thereby causing chronic pain. In this paper, we compile and review the articles published on the study of nociceptive sensitization and endometriosis pain mechanisms. Starting from the factors influencing the chronic pain associated with endometriosis, we explain the relationship between these factors and chronic inflammation and further elaborate on the potential mechanisms by which chronic inflammation induces nociceptive sensitization. We aim to reveal the possible mechanisms of endometriosis pain, as well as nociceptive sensitization, and offer potential new targets for the treatment of endometriosis pain.

Exploring novel non-opioid pathways and therapeutics for pain modulation

The opioid crisis has highlighted the urgent need for alternative pain management strategies. This review explores novel non-opioid targets and pathways involved in pain modulation, highlighting advancements in understanding and therapeutic potential. Pain, a multifaceted phenomenon with nociceptive, neuropathic, and inflammatory components, involves intricate molecular signaling cascades. Key pathways reviewed include voltage-gated sodium channels (Nav1.7, Nav1.8, Nav1.9), inflammasome complexes (NLRP3), the kynurenine pathway, prostaglandins, and bradykinin-mediated signaling. Emerging therapeutics such as selective Nav channel blockers, NLRP3 inhibitors, kynurenine pathway modulators, EP receptor antagonists, and bradykinin receptor antagonists offer promising alternatives to opioids. Despite challenges in clinical translation, these developments signal a paradigm shift in pain management, with precision-focused therapies poised to address unmet needs. This review emphasizes the importance of integrating molecular insights into the development of safer, more effective analgesics, setting the stage for transformative advancements in non-opioid pain relief.

Deep proteomics and network pharmacology reveal sex- and age-shared neuropathic pain signatures in mouse dorsal root ganglia

Our understanding of how sex and age influence chronic pain at the molecular level is still limited with wide-reaching consequences for adolescent patients. Here, we leveraged deep proteome profiling of mouse dorsal root ganglia (DRG) from adolescent (4-week-old) and adult (12-week-old) male and female mice to investigate the establishment of neuropathic pain in the spared nerve injury (SNI)-model in parallel. We quantified over 12,000 proteins, including notable ion channels involved in pain, highlighting the sensitivity of our approach. Differential expression revealed sex- and age-dependent proteome changes upon nerve injury. In contrast to most previous studies, our comprehensive dataset enabled us to determine differentially expressed proteins (DEPs), which were shared between male and female mice of both age groups. Among these, the vast majority (94 %) were also expressed and, in part, altered in human DRG of neuropathic pain patients, indicating evolutionary conservation. Proteome signatures represented numerous targets of FDA-approved drugs comprising both (i) known pain therapeutics (e.g. Pregabalin and opioids) and, importantly, (ii) compounds with high potential for future re-purposing, e.g. Ptprc-modulators and Epoetins. Protein network and multidimensional analysis uncovered distinct hubs of sex- and age-shared biological pathways impacted by neuropathic pain, such as neuronal activity and synaptic function, DNA-damage, and neuroimmune interactions. Taken together, our results capture the complexity of nerve injury-associated DRG alterations in mice at the network level, moving beyond single-candidate studies. Consequently, we provide an innovative resource of the molecular landscape of neuropathic pain, enabling novel opportunities for translational pain research and network-based drug discovery.

Progress in the mechanisms of pain associated with neurodegenerative diseases

Neurodegenerative diseases (NDDs) represent a class of neurological disorders characterized by the progressive degeneration or loss of neurons, impacting millions of individuals globally. In addition to the typical manifestations, pain is a prevalent symptom associated with NDDs, seriously impacting the quality of life for patients. The pathogenesis of pain associated with NDDs is intricate and multifaceted. Currently, the clinical management of NDDs-related pain symptoms predominantly relies on conventional pharmacological agents or physical therapy. However, these approaches often fail to produce satisfactory outcomes. This article summarizes the underlying mechanisms of major NDDs-associated pain: Neuroinflammation, Brain and spinal cord dysfunctions, Mitochondrial dysfunction, Risk gene and pathological protein, as well as Receptor, channel, and neurotransmitter. While numerous studies have investigated the downstream pathological processes associated with these mechanisms, there remains a significant gap in identifying the key initiating factors. Specifically, there is insufficient evidence for the upstream elements that activate microglia and astrocytes in neuroinflammation leading to pain in NDDs. Likewise, there is an absence of upstream factors elucidating how dysfunctions in the brain and spinal cord, as well as mitochondrial impairments, contribute to the development of pain. Furthermore, the specific mechanisms through which hallmark pathological proteins related to NDDs contribute to these pathological processes remain inadequately understood. The objective of this article is to synthesize the existing mechanisms underlying pain associated with NDDs, including Alzheimer's disease, Parkinson's disease, Huntington's disease, Schizophrenia, Amyotrophic lateral sclerosis, and Multiple sclerosis, while also identifying gaps and deficiencies in these mechanisms. This paper offers insights for future research trajectories. Given the intricate pathogenesis of NDDs-related pain, it emphasizes that a promising short-term strategy is combination therapy-intervening concurrently in multiple pathological processes-akin to the cocktail approach utilized in treating acquired immunodeficiency syndrome (AIDS). For long-term advancements, achieving breakthroughs in the treatment of the NDDs themselves will remain essential for alleviating accompanying pain symptoms.

MiRNA Expression in Long-Distance Runners with Musculoskeletal Pain: Implications for Pain Pathophysiology

Background: miRNAs are short, non-coding RNAs whose deregulation has been shown in painful processes, including musculoskeletal pain. This condition, which causes disability, impacts quality of life, and contributes to substantial healthcare costs, is also a critical issue in sports. In this case-control study, we evaluated the expression of four miRNAs involved in inflammation in runners with musculoskeletal pain and elucidated their functions and pathophysiological implications. Methods: A total of 17 runners with musculoskeletal pain and 17 age- and sex-matched runners without pain participated in this study. The levels of the miRNAs were evaluated by qRT-PCR. Bioinformatic tools were employed to identify the target genes and biological processes regulated by these miRNAs. Results: Compared to the controls, the runners with musculoskeletal pain exhibited significantly higher plasma levels of miR-133b (p = 0.02), miR-155-5p (p = 0.003) and let-7a-5p (p = 0.02). Multivariable regression analysis indicated that these three miRNAs exhibit a positive correlation (p < 0.05) with the presence of musculoskeletal pain, adjusted for age. Bioinformatic analysis suggested that the miRNAs hub genes are involved in regulatory processes, neuroinflammatory pathways, and human diseases that are associated with pain pathology. Conclusions: These results enhance our understanding of the potential role of miR-133b, miR-155-5p and let-7a-5p in pain-associated biological processes. The miRNA-mediated negative regulation of genes identified could explain the inflammatory and tissue repair processes in this population. Further studies are needed to confirm and validate the role of these miRNAs in painful conditions, especially considering the significant public health implications of managing inflammatory pain in sports.

The Antinociceptive Role of Nrf2 in Neuropathic Pain: From Mechanisms to Clinical Perspectives

Neuropathic pain, a chronic condition resulting from nerve injury or dysfunction, presents significant therapeutic challenges and is closely associated with oxidative stress and inflammation, both of which can lead to mitochondrial dysfunction. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, a critical cellular defense mechanism against oxidative stress, has emerged as a promising target for neuropathic pain management. Nrf2 modulators enhance the expression of antioxidant and cytoprotective genes, thereby reducing oxidative damage, inflammation, and mitochondrial impairment. This review explores the antinociceptive effects of Nrf2, highlighting how pharmacological agents and natural compounds may be used as potential therapeutic strategies against neuropathic pain. Although preclinical studies demonstrate significant pain reduction and improved nerve function through Nrf2 activation, several clinical challenges need to be addressed. However, emerging clinical evidence suggests potential benefits of Nrf2 modulators in several conditions, such as diabetic neuropathy and multiple sclerosis. Future research should focus on further elucidating the molecular role of Nrf2 in neuropathic pain to optimize its modulation efficacy and maximize clinical utility.