Search Results (162)

Chronic pain is increasingly understood as a neuroimmune disorder rather than a purely neuronal condition, in which immune mediators and immune-like signaling within the nervous system regulate nociceptive gain across peripheral tissues, dorsal root ganglia (DRG), spinal cord, and supraspinal networks. Seminal and recent syntheses show that microglia, macrophages, cytokines/chemokines, and innate immune sensors can initiate and maintain maladaptive plasticity and central sensitization, helping explain the frequent clinical dissociation between structural pathology, systemic inflammatory markers, and pain severity. However, immune biology is bidirectional: alongside pronociceptive pathways, a growing literature describes active “pain-resolving” programs that terminate sensitization and restore homeostasis, including regulatory T cell (Treg)–IL-10 signaling and specialized pro-resolving mediators (SPMs). A structured search of PubMed/MEDLINE, supplemented by Europe PMC and PubMed Central, was performed, and citation chasing through broad scholarly indices was used to identify high-impact reviews, meta-analyses, and translational mechanistic studies. Systematic biomarker syntheses in low back pain, neck pain, and fibromyalgia indicate modest and heterogeneous systemic inflammatory signals, underscoring the need for mechanistic endotyping and stage-specific interventions. Based on this evidence, a clinically oriented framework is presented that distinguishes immune-driven pain amplification from impaired resolution and outlines practical implications for assessment, biomarker interpretation, and precision-oriented trial design. Full article

Impaired blood–brain barrier (BBB) integrity is a common hallmark of neurological disorders associated with neuroinflammation, neurodegeneration and aging. The function of the BBB relies heavily on the interaction between astrocytes and endothelial cells, the most closely connected elements of the neurovascular unit. Under inflammatory conditions, astrocytes can undergo a range of metabolic changes, becoming pro-inflammatory and harmful to endothelial cells. Upon activation, astrocytes secrete a plethora of inflammatory mediators that severely disrupt the barrier function of the BBB. ω-3 polyunsaturated fatty acids (PUFAs), mainly docosahexaenoic and eicosapentaenoic acids, exhibit protective anti-inflammatory and antioxidant effects demonstrated in various neurological disorders. This review focused on the role of ω-3 PUFAs and their oxidative derivatives, specialized pro-resolving mediators, in preserving the BBB’s integrity via suppression of astrocytes’ activation or even promotion of their transition from an A1 to an A2 phenotype. We considered mainstream mechanisms of the anti-inflammatory and antioxidant effects of ω-3 PUFAs on reactive astrocytes, such as stimulation of the Nrf2/ARE and Wnt/β-catenin signaling pathways, inhibition of NF-κB/matrix metalloproteinase activity and the JAK/STAT3 signaling axis, as well as the contribution of ω-3 PUFA-activated GPCRs and PPAR transcriptional factors, particularly regarding the role of these mechanisms in preserving the BBB’s integrity. Full article

Background and Aims: Injectable lipid emulsions are an integral component of parenteral nutrition, providing energy as well as essential fatty acids. However, conventional soybean oil–based emulsions, which are rich in omega-6 fatty acids, are associated with a risk of exacerbating pro-inflammatory responses and immunosuppression, which is of particular importance in critically ill patients. The aim of this review is to present the significance of the composition of modern injectable lipid emulsions, with particular emphasis on emulsions containing fish oil as a source of omega-3 fatty acids (EPA and DHA), and to discuss their potential clinical benefits in selected critical conditions. Methods: This narrative review discusses the rationale for modern mixed-oil ILE, with a focus on fish oil as a source of EPA and DHA, and summarizes potential clinical benefits in selected critical care settings. Results: Modern injectable lipid emulsions combine long-chain triglycerides derived from soybean oil (omega-6), MCTs, olive oil (omega-9), and fish oil (omega-3). Adjusting the supply of individual fractions affects cell membrane structure, signaling pathways, gene expression, and the profile of lipid mediators produced, including specialized pro-resolving mediators (SPMs). ESPEN guidelines and international recommendations emphasize the need to use lipids in parenteral nutrition, preferring mixed-oil ILE supplemented with fish oil. The cited meta-analyses and clinical studies indicate that omega-3-containing emulsions may reduce the risk of infections and sepsis; shorten hospital stay, ICU length of stay, and duration of mechanical ventilation in patients with sepsis; as well as improve outcomes in acute pancreatitis; lower the risk of delirium; and reduce the incidence of delayed gastric emptying. Conclusions: Available data support the use of mixed-oil ILE supplemented with fish oil in the parenteral nutrition of critically ill patients as a strategy with immunomodulatory and pro-resolving potential that may translate into improved clinical outcomes. However, further well-designed randomized trials are needed to optimize dosing and administration regimens. Full article

Sarcopenia, characterized by the progressive loss of skeletal muscle mass, strength, and function, represents a major public health challenge in aging populations. This condition affects approximately 10–16% of community-dwelling older adults and is associated with increased risks of falls, frailty, functional decline, and mortality. The pathogenesis of sarcopenia involves chronic low-grade inflammation (inflammaging), oxidative stress, mitochondrial dysfunction, and anabolic resistance. Omega-3 polyunsaturated fatty acids (PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have emerged as promising nutritional interventions due to their anti-inflammatory properties and potential anabolic effects on skeletal muscle. This comprehensive review evaluates the current evidence on omega-3 PUFA supplementation for the attenuation and management of sarcopenia. Mechanistically, omega-3 PUFAs appear to enhance muscle protein synthesis through activation of the mTOR-p70S6K signaling pathway, reduce inflammation via specialized pro-resolving mediators (SPMs), improve mitochondrial bioenergetics, and attenuate muscle disuse atrophy. Clinical trials demonstrate that omega-3 supplementation, particularly at doses exceeding 2 g/day of combined EPA and DHA, can increase thigh muscle volume, handgrip strength, and one-repetition maximum strength in older adults. When combined with resistance exercise training, the benefits appear more pronounced, especially in women. However, heterogeneity in study designs, intervention durations, dosages, and outcome measures has produced some conflicting results. Large-scale trials, such as the MAPT study, have shown null findings for long-term supplementation alone, suggesting that omega-3s may be most effective as part of multimodal interventions. The evidence also supports benefits in clinical populations at risk for muscle wasting, including cancer patients experiencing cachexia and individuals with neuromuscular disorders. Future research should focus on identifying optimal dosing strategies, understanding sex-specific responses, and elucidating the mechanisms underlying the synergistic effects of omega-3s with exercise. Overall, omega-3 PUFA supplementation represents a safe, accessible, and potentially effective nutritional strategy for attenuating muscle decline in aging and clinical populations, though its benefits appear most pronounced when combined with resistance exercise as part of a multimodal approach. Full article

Chronic kidney disease (CKD) affects more than 10% of the population and is associated with a persistent, low-grade inflammatory state that accelerates tubulointerstitial fibrosis, worsens prognosis, and increases cardiovascular risk. This review aims to synthesize current knowledge on specialized pro-resolving mediators (SPMs) in the context of CKD pathophysiology, biomarkers, and therapeutic potential. We discuss key anti-inflammatory and pro-resolving mechanisms of SPMs that translate into nephroprotective and antifibrotic effects in experimental kidney models. The review summarizes data on EPA/DHA supplementation, including its impact on lipid profiles, inflammatory biomarkers (CRP, IL-6, TNF-α), and oxidative stress in patients with CKD. We also highlight contemporary analytical methods for biomarker assessment (LC-MS/MS, UHPLC-HRMS) and their potential for monitoring inflammatory activity across its phases (initiation, attenuation, resolution), CKD progression, and responses to ω-3/SPM-based interventions. Finally, we discuss the therapeutic potential of SPMs, as well as safety considerations and pharmacological interactions. In conclusion, SPMs and ω-3-derived mediators represent promising research and clinical targets as markers and modulators of inflammation in CKD, but require further validation in well-designed prospective studies. Full article

Background/Objectives: The retina is enriched in polyunsaturated fatty acids (PUFAs) which are indispensable for normal vision, and recent clinical studies have shown that dietary supplementation of ω-6-and ω-3-polyunsaturated fatty acids (PUFAs) can provide a protective role against retinopathy of prematurity (ROP). Our study aims to understand the mechanisms by which altering ω-6-and ω-3-polyunsaturated fatty acids (PUFAs) in the eye can protect against pathologic retinal neovascularization (NV). Methods: We interrogated the effects of endogenous ω-3-PUFA enrichment using transgenic fat-1 mice which convert ω-6-PUFAs to ω-3-PUFAs in the oxygen-induced retinopathy (OIR) murine model. In the OIR model, mice are exposed to 75% oxygen from postnatal day 7 (P7) to P12, then returned to room air (RA). We used a combination of immunofluorescence, bulk retinal RNA sequencing, and lipid mediator profiling by UHPLC-MS/MS in P17 mouse retinas to identify mechanisms underlying the protective effect against NV seen in fat-1 mice exposed to OIR. Results:Fat-1 OIR mice were protected against the development of retinopathy, demonstrating 15.1% less vaso-obliteration (75.5% relative reduction) after OIR and a 6.1% reduction in neovascularization (71.8% relative reduction) at P17 (p < 0.0001 for both). We found a dampened transcriptional response to OIR in the retina of fat-1 mice as compared to WT mouse retinas (198 vs. 782 genes, adjusted p-value < 0.01). Pathway analyses confirmed these findings, with significant OIR-induced transcriptional shifts in angiogenesis (adjusted p-value < 10⁻²⁷), inflammation (adjusted p-value < 10⁻²⁵), and microglial activation pathways (adjusted p-value < 10⁻⁹) in WT mouse retina that were not observed in fat-1 mice. Enrichment scores obtained through the integration of our bulk transcriptomics data with cell-resolved retina data indicate that the protective phenotype observed in fat-1 mice could be associated with intrinsic differences in microglia cell subtypes between WT and fat-1 mice. In situ, WT OIR mice demonstrated an increase in Iba1+ microglia compared to WT RA mice, whereas fat-1 OIR mice showed no difference when compared to fat-1 RA mice. Three ARA-derived oxylipins, 12-hydroxyeicosatetraenoic acid (12-HETE), prostaglandin D2 (PGD2), and thromboxane B2 (TXB2) demonstrated a pattern of upregulation in WT OIR compared to WT RA, but no upregulation in fat-1 OIR mice compared to fat-1 RA. Two EPA-derived specialized pro-resolving mediators and two LA-derived oxylipins were also differentially expressed. Conclusions: These findings show that a lower ω-6:ω-3 protects against neovascularization and is associated with attenuation of hyperoxia-induced microglial recruitment and activation, as well as inflammation and angiogenic signaling. Full article

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease associated with joint pain, stiffness, functional impairment, and reduced quality of life. Omega-3 (n-3) polyunsaturated fatty acids (PUFAs) have been proposed as adjunctive therapies for RA due to their anti-inflammatory and pro-resolving properties; however, evidence regarding high-dose docosahexaenoic acid (DHA) supplementation remains inconclusive. This exploratory study investigated the effects of 16 weeks of DHA-rich PUFA supplementation (2.5 g/d DHA and 0.5 g/d EPA) on clinical, functional, and inflammatory outcomes in individuals with moderate RA. A modest sample size of thirteen women (23–61 y) were randomized to receive either n-3 PUFA (n = 7) or placebo (n = 6). Clinical outcomes, quality of life, functional performance, cardiometabolic parameters, and systemic inflammatory markers were assessed before and after the intervention. Additionally, the inflammatory response of peripheral blood mononuclear cells (PBMCs) exposed to patient serum collected before and after supplementation, with and without the n-3 PUFA mediator resolvin D1 (RvD1), was evaluated. DHA-rich PUFA supplementation significantly reduced morning stiffness duration and improved RA-specific quality of life scores, without affecting systemic inflammatory or cardiometabolic markers. Serum obtained after supplementation attenuated TNF-α expression in PBMCs and produced effects comparable to RvD1 treatment. These findings suggest that DHA-rich PUFA supplementation improves clinically relevant outcomes in RA, potentially through local pro-resolving mechanisms. Full article

Background: This study aimed to investigate the potential biomechanical implications of biologically motivated modulation scenarios—Resolvin E1 (RvE1), Resolvin D1 (RvD1) and carvacrol—in the context of rotator cuff tears by using a reduced finite element (FE) modeling approach. The primary objective was to compare stress distribution and deformation behavior at the tendon–bone interface under standardized loading scenarios. Materials and Methods: A three-dimensional reduced FE model of the shoulder, including the scapula and proximal humerus, was constructed based on computed tomography data. A rotator cuff tear was represented at the tendon footprint on the greater tuberosity. Standardized boundary scenarios and loading vectors were applied. Three conceptual biological modulation scenarios (RvE1, RvD1, and carvacrol) were evaluated and compared with a baseline model representing a rotator cuff tear under identical geometric, material, boundary, and loading scenarios, without any biologically motivated modulation. Von Mises stress distribution at the greater tuberosity and tendon footprint, as well as maximum displacement of the proximal humerus, were analyzed descriptively and comparatively. Results: Compared with baseline scenarios, the RvE1 and RvD1 scenarios demonstrated reduced peak von Mises stress at the tendon footprint and lower overall humeral displacement. Peak footprint stress decreased from 10.8 MPa in the baseline model to 7.9 MPa (−26.9%) in the RvE1 scenario and to 8.6 MPa (−20.4%) in the RvD1 scenario. Similarly, maximum humeral displacement was reduced from 4.6 mm at baseline to 3.4 mm (−26.1%) with RvE1 and to 3.9 mm (−15.2%) with RvD1. In contrast, the carvacrol scenario exhibited increased localized stress concentration at the tendon footprint (12.4 MPa; +14.8%) and greater maximum displacement (5.8 mm; +26.1%). Conclusions: The findings suggested that modulation scenarios associated with specialized pro-resolving mediators (SPMs) were aligned with a more favorable mechanical environment at the tendon–bone interface compared with baseline scenarios, whereas the carvacrol scenario demonstrated less favorable biomechanical behavior under the modeled assumptions. Although the biological effects were represented conceptually and the results were interpreted as relative trends, this study highlighted the potential importance of resolution-oriented pathways in influencing tendon-to-bone biomechanics and supported further experimental and translational investigations in rotator cuff repair. Full article

Lipids are a diverse group of hydrophobic molecules including fats, oils, phospholipids, and steroids that are vital for numerous biological functions including energy storage, cellular structure, and signaling whose composition and metabolism undergo profound transformations with age. These age-related shifts due to increased lipid peroxidation, disrupted cholesterol homeostasis, and altered membrane phospholipid content, actively contribute to progressive loss in cellular homeostasis and pathogenesis of major age-related diseases. This review explores the critical role of lipids: as master regulators of cellular signaling pathways, and as key drivers of chronic inflammation and metabolic dysfunction. Dysregulated lipid metabolism is central to cardiovascular disease which is driven by altered myocardial energy substrate utilization and lipoprotein dynamics. In neurodegenerative disorders like Alzheimer’s and Parkinson’s disease, disruptions in ceramide, cholesterol, and specialized pro-resolving lipid mediators fuel neuroinflammation and protein aggregation. Furthermore, we explore the dual role of dietary lipids, which can either exacerbate or mitigate age-related decline, highlighting the potential of personalized nutritional approaches and lipid-targeting therapeutics. By integrating the mechanisms of lipid signaling, inflammation, and metabolic regulation, this analysis highlights that lipids are not merely passive structural components but active drivers of the aging process, positioning lipid metabolism as a promising frontier for interventions aimed at promoting health span and combating age-related disease. Full article

Background/Objectives: Maresin-1 (MaR1), a specialized pro-resolving mediator (SPM) derived from omega-3 fatty acids, has demonstrated potent anti-inflammatory and pro-resolving properties. However, its effects on depression-like behaviors and the associated dynamics of neuroinflammation, particularly in the context of chronic stress, are not yet fully understood. This study aimed to investigate the therapeutic potential of MaR1 in a chronic unpredictable stress (CUS) model and to monitor its dynamic effects on neuroimmune activity using longitudinal in vivo imaging. Methods: Adolescent male C57BL/6J mice were subjected to a 5-week CUS protocol. Mice exhibiting stable anhedonia were randomized to receive intraperitoneal injections of either MaR1 (5 µg/kg) or vehicle every other day for 4 weeks. During this period, CUS procedures were maintained. Depression-like behaviors were assessed using the sucrose preference test (SPT), tail suspension test (TST), and open field test (OFT). Dynamic changes in neuroinflammation were monitored via longitudinal [18F]DPA-714 positron emission tomography (PET) scans at baseline and after 2 and 4 weeks of treatment. Ex vivo analyses included immunofluorescence quantification of hippocampal microglia (ionized calcium-binding adaptor molecule 1, Iba1), astrocytes (glial fibrillary acidic protein, GFAP), and 18 kDa translocator protein (TSPO) co-expression, alongside quantitative polymerase chain reaction (qPCR) and Western blotting for inflammatory markers (IL-1β, IL-4, TSPO). Results: MaR1 treatment selectively alleviated depression-like behaviors, significantly reversing CUS-induced anhedonia in the SPT and improving locomotor activity, while its effect on despair-like behavior (TST) was not statistically significant. Longitudinal PET imaging revealed a biphasic neuroimmune response, characterized by an initial increase in [18F]DPA-714 standardized uptake value (SUV) at 2 weeks, followed by a return toward baseline at 4 weeks. Histologically, MaR1 reversed CUS-induced hippocampal microglial loss, resulting in a rebound of microglial numbers, and normalized astrocytic activation. At the molecular level, MaR1 dynamically modulated cytokine expression, culminating in a significant upregulation of the pro-resolving marker IL-4 and TSPO at 4 weeks. Conclusions: These findings indicate that Maresin-1 treatment is associated with behavioral improvement and dynamic modulation of glial activity and TSPO PET signals in the hippocampus. This study highlights the value of TSPO PET imaging for monitoring dynamic glial changes during therapeutic intervention and provides supportive evidence for targeting neuroimmune pathways in depression. Full article

Background: Chronic kidney disease (CKD) represents a state of persistent, sterile low-grade inflammation in which sustained innate immune activation accelerates renal decline and cardiovascular complications. Diet-induced gut dysbiosis and intestinal barrier dysfunction lower mucosal immune tolerance, promote metabolic endotoxemia, and position the gut as an upstream modulator of systemic inflammatory signaling along the gut–kidney axis. Scope: Most studies address microbiota-derived metabolites, food-derived bioactive peptides, or omega-3 fatty acids separately. This review integrates evidence across these domains and examines their convergent actions on epithelial barrier integrity, immune polarization, oxidative-inflammatory stress, and inflammasome-dependent pathways relevant to CKD progression. Key mechanisms: CKD-associated dysbiosis is characterized by reduced short-chain fatty acid (SCFA) production and increased generation and accumulation of uremic toxins and co-metabolites, including indoxyl sulfate, p-cresyl sulfate, trimethylamine N-oxide, and altered bile acids. Reduced SCFA availability weakens tight junction-dependent barrier function and regulatory immune programs, favoring Th17-skewed inflammation and endotoxin translocation. Bioactive peptides modulate inflammatory mediator networks and barrier-related pathways through effects on NF-κB/MAPK signaling and redox balance, while omega-3 fatty acids and specialized pro-resolving mediators support resolution-phase immune responses. Across these modalities, shared control points include barrier integrity, metabolic endotoxemia, oxidative stress, and NLRP3 inflammasome activation. Conclusions: Although evidence remains heterogeneous and largely preclinical, combined nutritional modulation targeting these convergent pathways may offer greater immunomodulatory benefit than isolated interventions. Future multi-omics-guided, factorial trials are required to define responder phenotypes and translate precision immunonutrition strategies into clinical CKD care. Full article

Polyunsaturated fatty acids (PUFAs), particularly omega-3 derivatives such as docosahexaenoic acid (DHA), are precursors of specialized pro-resolving mediators (SPMs) that actively orchestrate the resolution of inflammation. Among these, maresins (MaRs) have gathered increasing attention due to their potent immunomodulatory and tissue-regenerative properties. This review provides a comprehensive synthesis of the current knowledge on the biosynthesis, structural diversity, and biological functions of MaRs, with a focus on MaR1. We discuss the enzymatic pathways involved in the generation of MaR1, MaR2, MaRs conjugates in tissue regeneration (MCTRs), and maresin-like lipid mediators (MaR-Ls), highlighting their roles in modulating inflammatory responses, promoting phagocytosis, and restoring tissue homeostasis. Preclinical evidence from in vitro and in vivo models demonstrates that MaRs exert protective effects in a wide range of pathological contexts, including neuroinflammation, liver injury, cardiovascular dysfunction, pulmonary diseases, and metabolic disorders. Although their therapeutic promise is well-supported, key gaps remain in the understanding of MaRs biosynthesis, receptor specificity, and translational applicability. This review emphasizes the importance of advancing mechanistic and clinical research to fully harness MaRs as part of next-generation therapeutics in inflammation-driven diseases. Full article

Obesity-associated inflammation underlies much of cardiometabolic pathology, reflecting the convergence of chronic, low-grade systemic immune activation with region-specific maladaptation of adipose depots. Among these, epicardial adipose tissue (EAT)—a visceral fat layer contiguous with the myocardium and sharing its microvasculature—functions as a cardio-proximal immunometabolic interface that influences atrial fibrillation, heart failure with preserved ejection fraction, and coronary atherogenesis through paracrine crosstalk. These relationships extend beyond crude measures of adiposity, emphasizing the primacy of local inflammatory signaling, adipokine flux, and fibro-inflammatory remodeling at the EAT–myocardium interface. Of importance, substantial weight reduction only partially reverses obesity-imprinted transcriptional and epigenetic programs across subcutaneous, visceral, and epicardial depots, supporting the concept of an enduring adipose memory that sustains cardiovascular (CV) risk despite metabolic improvement. Accordingly, therapeutic strategies should move beyond weight-centric management toward mechanism-guided interventions. Resolution pharmacology—leveraging specialized pro-resolving mediators and their cognate G-protein-coupled receptors—offers a biologically plausible means to terminate inflammation and reprogram immune–stromal interactions within adipose and CV tissues. Although preclinical studies report favorable effects on vascular remodeling, myocardial injury, and arrhythmic vulnerability, clinical translation is constrained by pharmacokinetic liabilities of native mediators and by incomplete validation of biomarkers for target engagement. This review integrates mechanistic, depot-resolved, and therapeutic evidence to inform the design of next-generation anti-inflammatory strategies for obesity-related CV disease. Full article

Specialized pro-resolving mediators (SPMs), including lipoxins, resolvins, protectins, and maresins, actively terminate inflammation and restore tissue homeostasis. This review addresses how specialized pro-resolving mediators (SPMs) and their omega-3/omega-6 PUFA precursors influence inflammatory pathways, disease mechanisms, and therapeutic potential across major inflammatory skin disorders. MEDLINE/PubMed was searched on 4 October 2025. Eligible studies included experimental, animal, mechanistic human, and interventional research examining SPMs or omega-3/omega-6 fatty acids. Non-English articles, reviews, conference abstracts, and dietary questionnaire–only studies were excluded. Two reviewers independently screened and extracted data. Due to heterogeneity, a narrative synthesis was performed. No formal risk-of-bias assessment was undertaken Of 359 records, 57 studies were included (26 psoriasis, 24 atopic dermatitis, 7 acne; scarce hidradenitis suppurativa data). Preclinical data consistently demonstrated that SPMs modulate key inflammatory pathways, support epithelial repair, and help restore immune balance. Human studies revealed altered cutaneous and systemic lipid mediator profiles—characterized by reduced omega-3–derived SPMs and predominance of omega-6-driven inflammatory mediators—suggesting impaired resolution mechanisms across these disorders. Interventional studies showed that omega-3 supplementation may reduce inflammatory markers, improve barrier function, and alleviate clinical symptoms. Early evidence on SPMs analogues and receptor agonists indicates promising therapeutic potential, but clinical data remain sparse. The body of evidence is limited by scarce human data, small sample sizes, heterogeneous interventions and variable methods. Many studies rely on subjective or non-standardized clinical outcomes, and the predominance of experimental models further limits the translational relevance of current findings. In summary, disturbances in PUFA-derived lipid mediator pathways and insufficient activation of pro-resolving mechanisms may contribute to the persistence of cutaneous inflammation. Omega-3 supplementation and SPMs-based novel therapies therefore represent plausible adjunctive approaches; however, their therapeutic relevance requires confirmation in future mechanistic and clinical studies. Full article

Background/Objectives: Specialized pro-resolving lipid mediators (SPMs), such as Resolvin E1 (RvE1) and Resolvin D1 (RvD1), play a critical role in the resolution phase of inflammation. However, their relevance to tendon pathology and tissue-specific degeneration in rotator cuff tears remains unclear. This study aimed to investigate the relation between serum RvE1 and RvD1 levels and the morphological severity of tendon retraction and muscle fatty degeneration in patients with full-thickness rotator cuff tears. Methods: A total of 70 participants were included: 35 patients with full-thickness rotator cuff tears determined by magnetic resonance imaging (MRI) and 35 healthy controls. Tendon retraction and muscle fatty degeneration were graded using Patte and Goutallier classifications, respectively. Serum RvE1 and RvD1 levels were measured using enzyme-linked immunosorbent assay (ELISA). Group comparisons were performed using Welch’s t-test, and correlations were analyzed with Spearman’s coefficient. Results: RvE1 and RvD1 levels were significantly lower in patients compared to controls (p < 0.001). RvE1 showed a moderate positive correlation with Patte score (ρ = 0.37, p = 0.027), while no significant correlation was observed with Goutallier classification (ρ = 0.19, p = 0.27). RvD1 levels demonstrated no significant relationship with either morphological parameter. Conclusions: These findings suggest that decreased serum RvE1 levels are associated with the severity of tendon retraction but not with muscle fatty degeneration. Therefore, RvE1 may serve as a potential biochemical biomarker reflecting tendon damage severity and the impaired resolution of inflammation in rotator cuff tears. Full article