Search Results (2,293)

Erlotinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is widely used in cancer therapy; however, hepatotoxicity limits its clinical use. This study investigated the protective effects of Liv-52, a polyherbal hepatoprotective formulation, against erlotinib-induced hepatotoxicity in rats and compared its efficacy with melatonin. The animals (n = 24, Wistar albino rats) were randomly categorized into four groups: healthy (HG), erlotinib (ERG), Liv-52 + erlotinib (LEG), and melatonin + erlotinib (MEG). Liv-52 (50 mg/kg/day, orally) and melatonin (10 mg/kg/day, orally) were administered once daily for two weeks. Erlotinib (10 mg/kg, orally) was given every other day to ERG, LEG, and MEG groups for two weeks. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were measured. Hepatic malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), and catalase (CAT) levels were analyzed. Additionally, double immunofluorescence staining was performed to evaluate apoptotic (poly[ADP-ribose] polymerase-1 [PARP-1], apoptosis-inducing factor [AIF]), inflammatory (cyclooxygenase-2 [COX-2]), and anti-inflammatory (interleukin-10 [IL-10]) biomarkers in liver tissues. Histopathological examination was also conducted to assess structural alterations. Erlotinib significantly increased MDA, ALT, AST, and LDH while decreasing tGSH, SOD, and CAT (p < 0.001). Strong immunoreactivity for PARP-1, AIF, IL-10, and COX-2, as well as severe hydropic degeneration and necrosis, was observed in ERG (p < 0.05). Both Liv-52 and melatonin significantly ameliorated biochemical, histopathological, apoptotic, and inflammatory alterations (p < 0.05). Notably, Liv-52 demonstrated superior hepatoprotective efficacy compared to melatonin. These findings indicate that Liv-52 effectively attenuates erlotinib-induced hepatotoxicity by modulating oxidative stress, inflammatory responses, and apoptotic pathways, thereby preserving liver function and structural integrity. Full article

Background: Intervertebral disc degeneration (IVDD) is driven by the interplay between inflammatory signaling, extracellular matrix (ECM) degradation, and impaired cellular adaptation. Although several nutraceutical compounds have been reported to exert protective effects in IVDD-related models, their multitarget mechanisms within integrated molecular networks remain incompletely characterized. Methods: An in silico framework integrating molecular docking with network-based analyses was employed to evaluate resveratrol, quercetin, melatonin, curcumin, and baicalein against a predefined panel of IVDD-associated targets, within an exploratory in silico framework. Binding affinities and interaction profiles were assessed using molecular docking, followed by protein–protein interaction (PPI) network construction, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and hub gene identification. Results: Docking analyses revealed binding energies ranging from −4.59 to −13.25 kcal/mol, with curcumin and quercetin showing plausible docking poses across a subset of selected targets under the applied protocol. Network analysis showed a highly interconnected structure centered on key inflammatory regulators, including NFKB1, IL6, TNF, IL1B, STAT3, and NLRP3, together with ECM-associated components such as ACAN, COL2A1, SOX9, MMP13, and ADAMTS5. Enrichment analyses further suggested significant associations with inflammatory signaling pathways, cytokine regulation, and ECM organization. Conclusions: These findings are compatible with a distributed, multitarget interaction pattern of nutraceutical compounds within IVDD-associated molecular networks. By integrating molecular docking with network-based analyses, this study offers a system-level framework for interpreting previously reported effects within a disease-specific context. Docking-derived interaction patterns should be interpreted as qualitative and exploratory observations, as docking scores represent model-dependent estimates and do not establish comparable pharmacological effects across heterogeneous targets. The results should be considered hypothesis-generating and require experimental validation. Full article

Background/Objectives: Dietary antioxidants are frequently utilized by breast cancer (BC) patients to mitigate treatment-related toxicities and enhance quality of life. However, their clinical efficacy remains highly controversial due to conflicting epidemiological and clinical data. This review aims to critically evaluate the molecular mechanisms, clinical outcomes, and translational challenges of antioxidant supplementation in BC management. Methods: A comprehensive evaluation of current literature—encompassing observational cohorts, randomized controlled trials, and mechanistic in vitro/in vivo models—was conducted. The analysis focused on the pharmacological interactions of diverse bioactive compounds (polyphenols, vitamins, carotenoids) with BC progression and standard antineoplastic regimens. Results: Current evidence demonstrates a paradoxical, double-edged role of antioxidants in oncology. While specific interventions (e.g., Coenzyme Q10, melatonin) effectively ameliorate treatment-induced toxicities without compromising therapeutic efficacy, the concurrent administration of antioxidants during cytotoxic chemotherapy can inadvertently neutralize essential reactive oxygen species (ROS), correlating with increased disease recurrence and mortality. Furthermore, clinical translation is severely hindered by the intrinsic hydrophobicity of natural compounds, the lack of whole-food matrix standardization, and dose-dependent hepatotoxicity. Emerging targeted delivery systems, such as lipid nanoformulations, show significant potential in overcoming these pharmacokinetic barriers. Conclusions: The therapeutic viability of antioxidant supplementation in BC is not universal; it is heavily dictated by intrinsic tumor biology, specific treatment modalities, and chronopharmacology. These findings underscore a critical biological imperative to transition from generalized dietary guidelines toward a rigorous paradigm of precision nutritional oncology, strictly avoiding concurrent antioxidant supplementation during active oxidative therapies. Full article

Pinealectomy leads to melatonin deficiency, which is known to disrupt circadian clock regulation and may increase vulnerability of the hippocampus to oxidative stress and neuroinflammatory processes. The objective of this study was to examine the gene expression levels of circadian locomotor output cycles kaput (CLOCK), brain and muscle ARNT-like 1 (BMAL1), period circadian regulator 1 (PER1), cryptochrome circadian regulator 1 (CRY1), brain-derived neurotrophic factor (BDNF), and interleukin-6 (IL-6) in the hippocampus to elucidate the impact of pinealectomy-induced circadian dysregulation on these gene expressions and to assess its association with hippocampal alterations. A total of 30 Wistar rats were randomly divided into three groups: Control, Sham, and Pinealectomy (PNX) (n = 10 per group). Gene expression levels were analyzed using quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemical analysis was performed to assess caspase-3 and glial fibrillary acidic protein (GFAP) immunoreactivity. In addition, oxidative stress parameters, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), as well as the inflammatory marker tumor necrosis factor-alpha (TNF-α), were measured. The pinealectomy group showed a significant downregulation of BMAL1, BDNF, CLOCK, CRY1, and PER1 gene expression levels, with decreases ranging from approximately 60% to 83% compared with the sham and control groups, whereas IL-6 expression was significantly increased by approximately 185% (p < 0.05). Immunohistochemical analysis demonstrated significantly increased caspase-3 and GFAP immunoreactivity in the PNX group. Furthermore, pinealectomy resulted in a significant increase in MDA and TNF-α levels, accompanied by marked decreases in SOD, CAT, and GSH levels (p < 0.05). In conclusion, pinealectomy is associated with significant disruption of hippocampal circadian clock gene expression, accompanied by oxidative stress, neuroinflammation, and histopathological alterations. These findings highlight the critical role of circadian regulation in maintaining hippocampal cellular integrity. Full article

Oxidative stress critically affects cellular viability and function under in vitro culture conditions, often compromising physiological integrity of somatic cells used in livestock biotechnology. This study aimed to investigate hydrogen peroxide (H₂O₂)-induced oxidative stress in buffalo fibroblasts and evaluated the cytoprotective effects of melatonin, focusing on redox homeostasis, mitochondrial function, apoptosis, and antioxidant defence. Fibroblasts were exposed to graded concentrations of H₂O₂ (100–1000 µM) for 2 h, followed by treatment for 72 h in culture media with and without melatonin (10⁻⁹ M). Oxidative stress markers, including GSSG/GSH ratio, ROS generation, mitochondrial membrane potential (MMP), and apoptosis, were assessed using flow cytometry and biochemical assays, while antioxidant (GPx, SOD, CAT) and apoptotic (BAX, Caspase 9) gene expression was analyzed by qPCR. H₂O₂ exposure induced a dose-dependent increase in oxidative stress, evidenced by elevated ROS, redox imbalance, mitochondrial depolarization, and enhanced apoptosis. Severe oxidative damage was observed at higher H₂O₂ (500–1000 µM) concentrations. Melatonin (MT) significantly (p ≤ 0.05) alleviated oxidative stress under mild to moderate conditions (100–200 µM H₂O₂) by restoring redox homeostasis, preserving mitochondrial integrity, suppressing ROS accumulation, enhancing antioxidant defence, and reducing apoptosis. However, its protective efficacy was lost under severe oxidative stress, indicating a defined redox threshold beyond which cellular damage becomes irreversible. These findings suggest that melatonin exerts cytoprotective effect against oxidative stress within a limited oxidative window and provide mechanistic insights for improving fibroblasts culture systems in livestock biotechnology and regenerative applications. Full article

The use of colored LED lights is a tool for controlling the development of lymphoid organs and the immune system in general. This study aims to analyze the effects of using simple and combined colored LED lights throughout a 6 week period (1–42 days of age). In this study, 336 one-day-old chicks were used, separated randomly into four groups with different sex and lighting systems, with each group being divided into four separate replicates (4 × 21 birds). The chicks in the WL-Male and WL-Female were exposed to white LED light (WL, 400–760 nm) for 6 weeks, while the chicks in the G-GxB-BL-Male and G-GxB-BL-Female were exposed to a combination of monochromatic lights as follows: green (560 nm) from 1 to 14 days of age, green and blue (480–560 nm) for 15–28 days of age, and blue lights (480 nm) for 29–42 days of age. The use of a mixture of green and blue LED lights (G-GxB-BL) resulted in a significant decrease in the average daily feed intake and feed conversion ratio compared to white light, without causing changes in the body weight of the chicks, average daily gain, mortality rate, and coefficient of variability. G-GxB-BL lights also improved the morphological development of the bursa of Fabricius (BF) compared to white light by significantly increasing the organ index and the lymphoid follicle area. At the same time, G-GxB-BL light compared to white light improved B lymphocytes proliferation in the BF by significantly increasing the lymphocyte density in lymphoid follicles, as well as the number of PCNA-positive cells. This light treatment had these results due to the activation of melatonin receptors, which led to a significant increase in Mel1a-positive cells and a significant decrease in the number of RORα-positive cells. These results demonstrate that G-GxB-BL lights improved the growth performance and immune response in the BF of broiler chickens. Full article

This research aimed to develop glycerol–gelatin vaginal suppositories loaded with melatonin to enhance the localized effects of antineoplastic agents. The solubility of melatonin in different solvents was determined, and glycofurol, which is approved for pharmaceutical use, presented the highest solubilizing capacity. Furthermore, the cytotoxicity of melatonin incorporated into suppositories against HeLa cells was evaluated using MTT assays, individually and in combination with cisplatin. The results indicate that melatonin enhances the cytotoxic effects of cisplatin. The optimal formulation obtained from an experimental design was 33% gelatin, 1% PVA, 1% PEG 6000, 10% glycerol, 15% glycofurol, and 40% water. To ensure that the vaginal suppositories presented the necessary physical properties for optimal handling and application, tests were performed to determine weight uniformity, texture, surface features and disintegration time. Vaginal suppositories weighted around 1.43 g, showed Young’s modulus values of 7389.6 N/m² and hardness around 1100 g_f, and they disintegrated after 30 min at pH 4.2. Additionally, for in vitro melatonin release, FTIR and XRD tests confirmed the presence of melatonin in the formulation. It is concluded that the developed vaginal suppositories can be explored as potential vehicles for localized delivery of melatonin to the tumor site to enhance therapeutic outcomes. Full article

Since its discovery in higher plants, melatonin has attracted considerable attention for its antioxidant properties and its diverse roles in plant physiology and stress responses. However, its biosynthetic pathway remains only partially elucidated, particularly in horticultural crops of economic and nutritional importance, such as pepper (Capsicum annuum L.) fruits. In our previous work, we identified five genes encoding tryptophan decarboxylase (TDC), the first enzyme in the melatonin biosynthetic pathway in pepper. The present study expands on this by identifying and characterizing additional genes encoding enzymes involved in subsequent steps of the pathway, including four tryptamine 5-hydroxylase (T5H) genes, two serotonin N-acetyltransferase (SNAT) genes, three N-acetylserotonin O-methyltransferase (ASMT) genes, two caffeic acid O-methyltransferase (COMT) genes, and one N-acetylserotonin deacetylase (ASDAC) gene, representing a total of twelve newly identified genes. We further examined their expression in sweet pepper fruits and found that only nine of the identified genes are expressed in the fruit, with generally higher transcript levels during the unripe stages. Melatonin quantification in the California-type ‘Masami’ cultivar using UPLC with fluorescence detection (FD) revealed concentrations of 623 ng melatonin·g⁻¹ dry weight (DW) in green fruits and 431 ng melatonin·g⁻¹ DW in red fruits, consistent with the higher expression of melatonin biosynthetic genes in unripe fruit. Expression analysis of these genes by means of RNA-seq revealed differential modulation in response to exogenous melatonin treatments (20, 50, and 100 µM). To our knowledge, this is the first report demonstrating that exogenous melatonin regulates the expression of genes involved in its own biosynthetic pathway in sweet pepper fruits. Notably, treatment with 100 µM melatonin delayed ripening in these non-climacteric fruits, highlighting its potential biotechnological application for controlling fruit ripening and improving postharvest management. Full article

Background/Objectives: Burning mouth syndrome (BMS) is a chronic idiopathic orofacial pain disorder characterized by persistent intraoral burning in the absence of detectable mucosal alterations. Diagnosis is challenging due to the lack of specific biomarkers and the need to exclude numerous systemic and local conditions that can mimic oral burning. This literature review aims to summarize current and emerging therapeutic strategies for BMS. Methods: A structured and filtered search of PubMed, Scopus, and Web of Science identified studies evaluating pharmacological, phytotherapeutic, and non-pharmacological interventions. Results: Various antidepressants, anticonvulsants, benzodiazepines, H2 receptor antagonists, and low-dose naltrexone have demonstrated varying degrees of symptom reduction, while alpha lipoic acid (ALA) and phytomedicines such as capsaicin, Hypericum perforatum, Catuama, lycopene, crocin, and melatonin show mixed clinical benefits. Non-pharmacological approaches, including photobiomodulation (PBM), oral cryotherapy, neuromodulation techniques, and cognitive behavioral therapy, also provide meaningful symptom improvement in many patients. Conclusions: Across all modalities, therapeutic responses remain heterogeneous and generally incomplete, underscoring the absence of a universally effective treatment. Current evidence supports an individualized and multidisciplinary approach that integrates pharmacological, psychological, and adjunctive therapies to address the multifactorial nature of BMS. Full article

Background/Objectives: Circadian rhythm disruption is linked to cognitive decline, yet it remains unclear how behavioral and physiological rhythm markers are differently associated with cognition in amnestic mild cognitive impairment (aMCI). The primary aim of this study was to compare sleep–wake timing, rest–activity rhythm (RAR), and dim light melatonin onset (DLMO) between patients with aMCI and cognitively normal controls. Exploratory analyses further examined their associations with domain-specific cognitive performance. Methods: Eighteen aMCI patients and 21 cognitively normal controls (NC) enrolled. Cognitive function was assessed using the Korean version of the Consortium to Establish a Registry for Alzheimer’s Disease Neuropsychological Battery (CERAD-K). Participants underwent 5-day actigraphy to assess sleep–wake timing and non-parametric RAR variables, including interdaily stability (IS), intradaily variability (IV), and relative amplitude (RA). DLMO was determined from hourly salivary melatonin samples collected over five hours before sleep onset under dim-light conditions. Group comparisons of circadian markers were conducted as the primary analyses, and generalized linear models were used for exploratory analyses of associations between circadian markers and cognitive outcomes. Results: Groups did not significantly differ in sleep–wake timing, RAR parameters and DLMO. Sleep–wake timing variables and DLMO were not significantly associated with cognitive performance. Higher IS was associated with better visuospatial memory and executive function, whereas higher RA was associated with poorer verbal memory among aMCI patients. Conclusions: Although sleep–wake timing and melatonin phase did not differ between groups nor predict cognitive performance, higher daily rhythm stability was linked to better non-verbal memory and executive functioning. In contrast, high RA may relate to poorer verbal memory in aMCI, suggesting that elevated RA may not reflect true circadian robustness required for optimal cognition. Full article

Background/Objectives: Growing evidence indicates that melatonin contributes to kidney development and function, while disruptions of fetal circadian signaling have been linked to congenital anomalies of the kidney and urinary tract (CAKUT). This study aimed to characterize the developmental and spatial expression patterns of melatonin receptors MTNR1A and MTNR1B in normal human fetal kidneys and in CAKUT phenotypes. Methods: This study analyzed 40 human fetal kidney specimens, including healthy controls and CAKUT cases (horseshoe kidneys, duplex kidneys, and dysplastic kidneys), obtained from spontaneous abortions and pregnancy terminations. Samples were classified into developmental phases Ph2–Ph4 according to established morphological criteria. Immunofluorescence staining was used to visualize MTNR1A and MTNR1B expression. Quantitative analysis was performed using ImageJ, measuring the fluorescence area percentage. Statistical comparisons were conducted using a two-way ANOVA. Results: In control kidneys, MTNR1A expression was predominantly observed in glomeruli and interstitial cells and showed a descending trend across developmental stages, whereas MTNR1B was localized to glomeruli and strongly to the apical membranes of tubules, particularly distal tubules, without substantial developmental variation. CAKUT phenotypes exhibited higher expression of both receptors compared to controls. Significant phase-dependent differences in MTNR1A expression were observed in horseshoe, duplex, and dysplastic kidneys. MTNR1B expression decreased across developmental stages in dysplastic kidneys and differed significantly between Ph3 and Ph4 in duplex kidneys. At Ph3, duplex kidneys showed the highest MTNR1B expression. Conclusions: Altered developmental expression patterns of MTNR1A and MTNR1B in CAKUT suggest an association between melatonin signaling and abnormal human kidney development. Full article

Melatonin is reported to exert two types of actions: those based on its interaction with cognate receptors (characterized by very high affinities—1 nM and below), and those mediated by unknown targets (characterized by high concentrations—100 µM and above). Whereas receptor-mediated activities are known to regulate circadian rhythm, the high-dose effects are reported to be independent of these receptors and to produce literally dozens of beneficial effects in almost all human diseases, including cancer, neurodegenerative disorders, viral infections, obesity and many others. In the present opinion paper, we discuss this extensive set of claims and place them in perspective with a sum of evidence that collectively challenges the validity of these alleged beneficial effects. Full article

Sleep is tightly regulated by thermoregulatory processes that include core body temperature (CBT) modulation, the distal–proximal temperature gradient (DPG), and melatonin rhythms. In this review, we examine how these factors intersect with sleep physiology and contribute to the pathophysiology of common sleep disorders such as ADHD, insomnia, narcolepsy, Obstructive Sleep Apnea (OSA), depression, and Restless Legs Syndrome (RLS). We discuss evidence showing that delayed or disrupted CBT minima, impaired DPG, and altered melatonin secretion can prolong sleep latency, fragment rest, and lead to daytime symptoms. In addition, we explore temperature-based interventions, including foot baths, passive body heating, whole-body hyperthermia, and adjustments in room temperature, which have demonstrated potential to mitigate symptoms and enhance sleep quality. Collectively, these findings emphasize the need for personalized interventions to address thermoregulatory disruptions, presenting a noninvasive avenue for more effective sleep disorder management. Full article

Background/Objectives: Oxidative stress plays an important role in the pathophysiology of endometriosis, contributing to inflammation, immune dysregulation, and lesion progression. This has led to growing interest in antioxidant-based strategies as potential supportive interventions. Methods: A literature search was conducted using PubMed, Scopus, and Web of Science databases, covering studies published from database inception until the end of January 2026. The review focused on clinically relevant endpoints, including pain intensity, markers of inflammation and oxidative stress, reproductive parameters, and quality of life. Results: Among the analyzed interventions, the most consistent clinical effects were observed with melatonin, with randomized controlled trials indicating a moderate reduction in pain. N-acetylcysteine shows potentially beneficial effects; however, the available clinical data remain limited and heterogeneous. For other supplements, the evidence is inconsistent or insufficient to support clear clinical conclusions, and in many cases relies on indirect or mechanistic findings rather than well-established clinical outcomes. Conclusions: Current evidence does not support the use of non-mineral antioxidant supplements as standalone therapy for endometriosis. They may be considered as adjunctive strategies, although their clinical effectiveness remains uncertain and requires confirmation in well-designed randomized clinical trials. Full article

To develop safe and effective preservatives for fresh-cut produce, this study elucidates the multi-pathway mechanisms through which Melatonin (MT) regulates postharvest senescence in fresh-cut potatoes. Treatment with 0.1 mmol/L exogenous MT effectively inhibited browning and softening during storage. In terms of browning control, MT suppressed PPO and POD activities by 46% and ~10% at the end of storage (day 12), while enhancing enzymatic and non-enzymatic antioxidant capacity by 1.1- to 1.6-fold on average throughout storage. This alleviated oxidative damage and membrane lipid peroxidation, thereby reducing tissue browning. Regarding texture maintenance, MT downregulated PME and cellulase activities by 23% and 19% at the end of storage, activated phenylpropanoid metabolism, and inhibited starch degradation (maintaining 19% higher starch content), thus preserving cell wall structure and firmness (9.2% higher at the end of storage). Further analysis revealed that MT antagonized ethylene biosynthesis, upregulated StMYB168 expression (5.8-fold higher than control on average), and activated endogenous MT biosynthesis, establishing a self-sustaining positive regulatory cycle. Correlation analysis confirmed close relationships among physiological processes, signaling responses, and quality traits, with significant associations between firmness and starch content (r = 0.72), color indices and PPO/POD (|r| > 0.65), and MT biosynthesis genes and metabolic pathways (r = 0.65–0.75) (p < 0.01). Full article