Role of Nrf2 in aging, Alzheimer's and other neurodegenerative diseases

NAD+ glycohydrolases-CD38 as a therapeutic target in aging: physiological roles, molecular mechanisms, and future opportunities in anti-aging research

As individuals age, tissue homeostasis and functionality gradually deteriorate, leading to the occurrence and advancement of age-related illnesses. Nicotinamide adenine dinucleotide (NAD+) is essential for metabolism and cellular energy generation. The significance of maintaining adequate the levels of NAD+ within biological systems to ameliorate age-related tissue degeneration and prevent age-related illnesses in senescent animals is now widely recognized, emphasizing the importance of increasing NAD+ levels. Cluster of differentiation 38 (CD38), a multifunctional enzyme, plays a significant role in maintaining the cellular equilibrium of NAD+ through the consumption of NAD+. Recent research has shown a correlation between aging and upregulation of CD38 expression, potentially resulting in a reduction in NAD+ with increasing age. In contrast, the lack of CD38 has been shown to have a beneficial effect on slowing the aging process. Consequently, CD38 has been increasingly identified as a potential therapeutic target for interventions aimed at combatting aging. This study investigated the physiological roles of CD38, its ramifications in the aging process, possible molecular mechanisms associated with its involvement in aging-related diseases, and possible therapeutic applications of small-molecule inhibitors targeting CD38 in the context of aging. In this review, we provide a comprehensive analysis of the potential applications and future opportunities of CD38 in anti-aging research.

Quercetin, as a Nutritional Supplement, Protects against Iron Overload-Induced Testicular Dysfunction via Inhibiting Ferroptosis

Iron overload is closely associated with testicular dysfunction and ferroptosis, but the mechanism is elusive. Quercetin (Q) is a natural flavonoid with significant pharmacological effects such as antioxidant, anti-inflammatory, and antiaging. Purified quercetin can be used as a dietary supplement. However, the cellular autonomous mechanisms responsible for regulating ferroptosis in the testicular reproductive system and the molecular mechanisms of Q in treating testicular injury remain to be elucidated. In the study, based on RNA-seq results, we found that iron overload causes ferroptosis in testicular cells through the SLC39A14 and HO1 pathways, thereby promoting testicular dysfunction, including hormone secretion disorders and blood-testis barrier (BTB) dysfunction. Interestingly, using RNA-seq, we found that ferroptosis and NRF2 signaling pathways may be involved in the treatment of testicular dysfunction caused by iron overload with Q. Collectively, this study demonstrates for the first time that Q can impede the progression of ferroptosis by targeting the activation of NRF2 in the testes, which may provide a new therapeutic approach to alleviate iron overload-induced testicular injury.

Alzheimer's Disease: A Review of Molecular Mechanisms and Therapeutic Implications by Targeting Sirtuins, Caspases, and GSK-3

Alzheimer's disease (AD) is a neurodegenerative disease with a significant impact on global public health. The primary hallmarks of the disease included amyloid-beta peptide (Aβ) deposition, neurofibrillary tangles (NFT), and synaptic loss. Sirtuins, a group of NAD+-dependent deacetylase enzymes, are key regulators of AD pathogenesis. SIRT1, a member of sirtuins, has been identified to possess neuroprotective properties. Thus, its promising enhancers are included. Further, SIRT2 promising inhibitors are reviewed for therapeutic efficacy. The extrinsic and intrinsic apoptotic pathways of caspases are mediated by CD95 and DNA damage. The promising inhibitors Q-VD-OPh and minocycline are found to be specific for caspase-7 and caspase-3, respectively. Primarily, glycogen synthase kinase-3β (GSK-3β) is found to be involved in the generation of phosphorylated tau. The promising GSK-3 inhibitor included the COB-187 (IC50 = 370 nM) and maleimide-derivative (compound 33, IC50 = 0.09 μM). This review highlights the molecular mechanisms of sirtuin, caspase, and GSK-3 in the pathophysiology of AD. Further, promising modulators specific to these targets are described.

GLCCI1 ameliorates mitochondrial dysfunction in allergic asthma mice via DYRK1A/FAM117B-dependent NRF2 activation

Allergic asthma significantly impacts individuals' quality of life and work. This study aimed to investigate the specific mechanisms by which GLCCI1 regulated mitochondrial dysfunction in allergic asthma mice. In an ovalbumin (OVA)-induced allergic asthma mouse model, mitochondrial dysfunction in airway epithelium was observed, characterized by reduced ATP production, decreased mtDNA copy number, ROS accumulation, and mitophagy activation (upregulated PINK1/OPTN). In vitro experiments confirmed that OVA stimulation impaired mitochondrial membrane potential, exacerbated oxidative stress, and reduced cell viability in bronchial epithelial cells (BECs). Moreover, GLCCI1 regulated DYRK1A/FAM117B and KEAP1/NRF2 axis while inhibiting NRF2 ubiquitination degradation. Mechanistically, GLCCI1 overexpression reversed OVA-induced mitochondrial dysfunction by activating NRF2 signaling pathway via enhancing DYRK1A/FAM117B. In allergic asthma mice, GLCCI1 overexpression improved airway hyperresponsiveness, reduced inflammatory infiltration, restored alveolar structure, and decreased IL-4/IL-5/IL-13 levels. In summary, GLCCI1 ameliorated mitochondrial dysfunction in allergic asthma mice via the DYRK1A/FAM117B/NRF2 pathway, offering a potential therapeutic target for allergic asthma.

Resetting the aging clock through epigenetic reprogramming: Insights from natural products

Epigenetic modifications play a critical role in regulating gene expression under various physiological and pathological conditions. Epigenetic modifications reprogramming is a recognized hallmark of aging and a key component of the aging clock used to differentiate between chronological and biological age. The potential for prospective diagnosis and regulatory capabilities position epigenetic modifications as an emerging drug target to extend longevity and alleviate age-related organ dysfunctions. In the past few decades, numerous preclinical studies have demonstrated the therapeutic potential of natural products in various human diseases, including aging, with some advancing to clinical trials and clinical application. This review highlights the discovery and recent advancements in the aging clock, as well as the potential use of natural products as anti-aging therapeutics by correcting disordered epigenetic reprogramming. Specifically, the focus is on the imbalance of histone modifications, alterations in DNA methylation patterns, disrupted ATP-dependent chromatin remodeling, and changes in RNA modifications. By exploring these areas, new insights can be gained into aging prediction and anti-aging interventions.

Mitophagy in Alzheimer's disease and other metabolic disorders: A focus on mitochondrial-targeted therapeutics

Mitochondria, as central regulators of cellular processes such as energy production, apoptosis, and metabolic homeostasis, are essential to cellular function and health. The maintenance of mitochondrial integrity, especially through mitophagy-the selective removal of impaired mitochondria-is crucial for cellular homeostasis. Dysregulation of mitochondrial function, dynamics, and biogenesis is linked to neurodegenerative and metabolic diseases, notably Alzheimer's disease (AD), which is increasingly recognized as a metabolic disorder due to its shared pathophysiologic features: insulin resistance, oxidative stress, and chronic inflammation. In this review, we highlight recent advancements in pharmacological interventions, focusing on agents that modulate mitophagy, mitochondrial uncouplers that reduce oxidative phosphorylation, compounds that directly scavenge reactive oxygen species to alleviate oxidative stress, and molecules that ameliorate amyloid beta plaque accumulation and phosphorylated tau pathology. Additionally, we explore dietary and lifestyle interventions-MIND and ketogenic diets, caloric restriction, physical activity, hormone modulation, and stress management-that complement pharmacological approaches and support mitochondrial health. Our review underscores mitochondria's central role in the pathogenesis and potential treatment of neurodegenerative and metabolic diseases, particularly AD. By advocating for an integrated therapeutic model that combines pharmacological and lifestyle interventions, we propose a comprehensive approach aimed at mitigating mitochondrial dysfunction and improving clinical outcomes in these complex, interrelated diseases.

Microglial NOX2 as a therapeutic target in traumatic brain injury: Mechanisms, consequences, and potential for neuroprotection

Traumatic brain injury (TBI) is a leading cause of long-term disability worldwide, with secondary injury mechanisms, including neuroinflammation and oxidative stress, driving much of its chronic pathology. While NADPH oxidase 2 (NOX2)-mediated reactive oxygen species (ROS) production is a recognized factor in TBI, the specific role of microglial NOX2 in perpetuating oxidative and inflammatory damage remains underexplored. Addressing this gap is critical, as current therapeutic approaches primarily target acute symptoms and fail to interrupt the persistent neuroinflammation that contributes to progressive neurodegeneration. Besides NOX, other ROS-generating enzymes, such as CYP1B1, COX2, and XO, also play crucial roles in triggering oxidative stress and neuroinflammatory conditions in TBI. However, this review highlights the pathophysiological role of microglial NOX2 in TBI, focusing on its activation following injury and its impact on ROS generation, neuroinflammatory signaling, and neuronal loss. These insights reveal NOX2 as a critical driver of secondary injury, linked to worsened outcomes, particularly in aged individuals where NOX2 activation is more pronounced. In addition, this review evaluates emerging therapeutic approaches targeting NOX2, such as GSK2795039 and other selective NOX2 inhibitors, which show potential in reducing ROS levels, limiting neuroinflammation, and preserving neurological functions. By highlighting the specific role of NOX2 in microglial ROS production and secondary neurodegeneration, this study advocates for NOX2 inhibition as a promising strategy to improve TBI outcomes by addressing the unmet need for therapies targeting long-term inflammation and neuroprotection. Our review highlights the potential of NOX2-targeted interventions to disrupt the cycle of oxidative stress and inflammation, ultimately offering a pathway to mitigate the chronic impact of TBI.

Targeting mitochondria with natural polyphenols for treating Neurodegenerative Diseases: a comprehensive scoping review from oxidative stress perspective

Neurodegenerative diseases are a class of conditions with widespread detrimental impacts, currently lacking effective therapeutic drugs. Recent studies have identified mitochondrial dysfunction and the resultant oxidative stress as crucial contributors to the pathogenesis of neurodegenerative diseases. Polyphenols, naturally occurring compounds with inherent antioxidant properties, have demonstrated the potential to target mitochondria and mitigate oxidative stress. This therapeutic potential has garnered significant attention in recent years. Investigating the mitochondrial targeting capacity of polyphenols, their role in functional regulation, and their ability to modulate oxidative stress, along with exploring novel technologies and strategies for modifying polyphenol compounds and their formulations, holds promise for providing new avenues for the treatment of neurodegenerative diseases.

Sake lees extract obtained using a novel continuous phase-transition extraction method: evaluation of its bioactive composition, anti-aging efficacy and mechanism

For the high-value utilization of sake lees (SL), it is essential to explore its potential as a resource for anti-aging bioactives. However, the efficient extraction of SL, the compositional benefits provided, and the resulting anti-aging efficacy in vivo remain to be explored. Thus, a novel continuous phase-transition extraction (CPE) method, an amino acid analyzer, LC-MS, and GC-MS, as well as a classic anti-aging model of Caenorhabditis elegans (C. elegans) were adopted. The results showed that compared to ultrasound-assisted extraction, the total amino acid content of SL extract (SLE) obtained using 80% ethanol in CPE increased by 39.64%, with a notable enhancement in the in vitro scavenging ability of free radicals (p < 0.05). In SLE, the hydrophobic, acidic, and basic amino acids with antioxidant activity accounted for 77.11% of total amino acids. New potential anti-aging compounds were identified, including Lys-Gln, Leu-Arg-Lys, and sphinganine. In particular, 4 mg mL-1 SLE not only promoted a 19.32% increase in the lifespan of C. elegans by enhancing oxidative stress and neuroprotective effects but also ameliorated age-related phenotypes like motoricity and age pigment. Further exploration revealed that the efficacy of SLE is mediated by SKN-1/Nrf2 and HSF-1 pathways, which can be confirmed by the upregulation of key genes, such as skn-1 and hsf-1, especially by inducing a 72.73% increase in nuclear transfer of the transcription factor SKN-1/Nrf2. Taken together, SLE obtained by CPE was abundant in bioactives and contains novel components, thus exerting prominent anti-aging effects in vivo. This study provides a new way to obtain anti-aging active substances efficiently, which is beneficial for application in the fields of health foods and cosmetics.

Far-Infrared Radiation Ameliorates the Cognitive Dysfunction in an Alzheimer's Disease Transgenic Mouse via Modulating Jak-2/Stat3 and Nrf-2/HO-1 Pathways

Alzheimer's disease (AD) is the primary cause of dementia in the elderly. However, effective therapies that modify the disease process in AD remain elusive. Far-infrared radiation (FIR) is commonly utilized as a complementary treatment a range of disease, for example insomnia and rheumatoid arthritis. In this research, we explored how FIR light impacts the cognitive functions of TgCRND8 AD mice and elucidated its underlying molecular mechanism. The cognitive capabilities of TgCRND8 mice assessed by employing the Morris water maze. The concentrations of IL-1β, TNF-α, IL-4, Aβ40, and Aβ42 protein were assessed by enzyme-linked immunosorbent assay. Immunostaining was conducted to assess the Aβ deposits and microglial presence in the brains of TgCRND8 mice. Western blot was applied to detect the protein expressions of tau phosphorylation, amyloid-β (Aβ) production, Jak-2/Stat3, and Nrf-2/HO-1 pathways. The results indicated that FIR light notably ameliorated the cognitive impairments of the AD mice, reduced both Aβ deposition and tau protein hyperphosphorylation at sites of Thr205, Ser369, Ser404, and Thr181, suppressed the release of TNF-α and IL-1β, attenuated the ratios of p-Jak-2/Jak-2 and p-Stat3/Stat3, while increased the protein levels of IL-4, Nrf-2, and HO-1 in the brains of TgCRND8 mice. These findings amply demonstrated that FIR light ameliorated cognitive deficits of TgCRND8 mice via reducing both Aβ burden and tau protein hyperphosphorylation, suppressing the neuroinflammation, and restoring the levels of the oxidative-related proteins through modulating Jak-2/Stat3 and Nrf-2/HO-1 pathways. These experimental findings indicate that FIR light treatment is a promising treatment approach for AD.

A Natural Compound Methylnissolin: Physicochemical Properties, Pharmacological Activities, Pharmacokinetics and Resource Development

Methylnissolin (also known as Astrapterocarpan) is an isoflavonoid compound featuring a pterocarpan core structure. To date, leguminous plants of the genus Astragalus remain the exclusive natural source of Methylnissolin and its glycoside derivative, Methylnissolin-3-O-glucoside. Upon oral administration, Methylnissolin and its glycosides enter systemic circulation and modulate signaling pathways such as RIPK2/ASK1, PI3K/AKT, IκB/NF-κB, MAPK, and Nrf2/HO-1. Their pharmacological activities span anti-inflammatory, antioxidant, glucose-lipid metabolism regulation, and antitumor effects, underscoring their broad potential for drug development. This review comprehensively evaluates the physicochemical properties, pharmacological activities, mechanisms of action, pharmacokinetic characteristics, and toxicological profile of Methylnissolin and its glycoside derivatives. Notably, we systematically elucidate the metabolic fate of methylnissolin, identifying hydroxylation, demethylation, dimerization, hydration, and dehydrogenation as predominant biotransformation pathways. Furthermore, the influence of factors such as plant variety, geographical origin, and processing methods on Methylnissolin and its glycoside content in Astragalus membranaceus is analyzed, providing crucial insights for drug development and resource utilization.

Glucomannogalactan inhibits senescence by promoting nuclear translocation of NRF2

For a potential resource to improve healthspan, polysaccharides present unique advantages in terms of side effects and long-term use owing to their low cytotoxicity. In this study, we demonstrate that a glucomannogalactan (PGP) derived from Pleurotus geesteranus extends the healthspan of both naturally senescent and therapy-induced senescence (TIS) mice. Daily treatment of naturally senescent mice with PGP resulted in a reduced accumulation of senescent cells and alleviation of senescence-related parameters, including metabolic dysfunction, underlying lesions in multiple organs, and oxidative damage. PGP treatment also attenuated senescence in TIS mice. Furthermore, in an in vitro model of oxidative stress-induced senescence using a human cell line, we discovered that PGP alleviated senescence by promoting the nuclear translocation of NRF2. This study suggests that PGP may extend the healthspan of senescent mice by facilitating the nuclear translocation of NRF2.

Bibliometric and graphical analysis of ferroptosis and aging research: Trends, gaps, and future directions

Over the past 12 years, a significant body of evidence derived from extensive research has underscored the pivotal involvement of ferroptosis in the mechanisms underlying aging. Despite the growing body of literature on this topic, there remains a paucity of analytical and descriptive studies that explore its trajectory, key research directions, current trends, primary focal points, and future outlooks. This research endeavors to provide an exhaustive overview of the advancements in understanding the relationship between ferroptosis and aging over the past 12 years. The dataset utilized in this study was extracted from the Web of Science, encompassing records from January 1, 2012, through June 19, 2024. We conducted comprehensive bibliometric and visual analyses using advanced analytical tools. The results highlight China's dominant contribution, which accounts for 48.52 % of total publications, positioning it as a key player in this research area. Leading institutions, including Columbia University, Southern Medical University, and the Salk Institute for Biological Studies, demonstrate high research productivity. Pamela Maher and Gu Wei are identified as the most prolific researchers in this field. Free Radical Biology and Medicine is the leading journal, publishing the most articles in this field. This study identifies mitochondrial diseases, arrhythmias, Parkinson's disease, hepatocellular carcinoma, and iron-refractory iron deficiency anemia as the key diseases investigated in this field. This bibliometric evaluation offers critical perspectives for both experienced scholars and early-career researchers, enabling the identification of novel ideas and advancements within this domain.

Biomarkers in Alzheimer's disease: new frontiers with olfactory models

Alzheimer's disease (AD), the leading cause of dementia worldwide, presents a significant diagnostic challenge, as clinical diagnoses are often made at advanced stages when neurodegenerative damage is already extensive. The study of biomarkers is necessary for improving identification, prognosis, and disease monitoring. Current research has primarily focused on cerebrospinal fluid and imaging biomarkers, including amyloid-β (Aβ1-42), phosphorylated tau, and total tau. However, these methods are invasive, expensive, and not widely accessible. Emerging approaches aim to identify novel, cost-effective, and minimally invasive biomarkers, particularly from blood-based and other peripheral sources. This review explores the role of olfactory neuronal precursors (ONPs) derived from the olfactory neuroepithelium (ONE) as a promising and innovative model for biomarker discovery in AD. ONPs can be non-invasively obtained directly from patients, offering a unique resource to study AD-related pathophysiological mechanisms. These neuronal lineage cells exhibit characteristics that make them a reliable surrogate model for central nervous system studies, enabling the evaluation of established biomarkers and facilitating the identification of novel candidates. Additionally, we discuss the potential of ONPs to enhance clinical practice through their accessibility and suitability for high-throughput biomarker analysis. By integrating the study of ONPs with existing biomarker research, this review highlights new frontiers in the quest to refine diagnostic tools and advance our understanding of Alzheimer's disease, paving the way for innovative strategies in early detection and personalized management.

Molecular mechanisms of MAPK9, BAX, and TFEB proteins: Genetic correlations between oxidative stress and autophagy pathways in Alzheimer's disease

Alzheimer's disease (AD) is a complex neurodegenerative disease whose pathological mechanisms involve dysregulation of oxidative stress and autophagy pathways. MAPK9, BAX and TFEB were used as key proteins. Wayne analysis was used to identify genes associated with autophagy and oxidative stress, and protein-protein interaction (PPI) networks were constructed to study the associations between key genes. The key genes were mined by machine learning algorithm and prognostic marker models were constructed. The immune characteristics of AD were investigated by gene collection enrichment analysis (GSEA) and immunoresponse pathway enrichment analysis, and the clinical application potential was evaluated by drug prediction and molecular docking analysis. Finally, Mendelian randomization (MR) analysis was used to verify the causal relationship between key genes and AD. The results showed that we successfully identified several genes associated with Alzheimer's disease, including MAPK9, BAX, and TFEB. GSEA analysis showed their active involvement in the immune response, indicating the importance of immune function in AD. Drug prediction models reveal potential therapeutic targets for these key genes.

TAZ/NRF2 positive feedback loop contributes to proliferation in bladder cancer through antagonistic ferroptosis

Bladder cancer (BLCA) is a prevalent malignancy characterized by high recurrence and metastasis rates. Emerging evidence suggests that the NRF2-GPX4 axis is closely associated with ferroptosis. The transcriptional coactivator with PDZ-binding motif (TAZ) plays a crucial role in regulating ferroptosis; however, its role in BLCA remains unclear. In our study, we found that TAZ was markedly upregulated in BLCA tissues and BLCA cell lines. Gene set enrichment analysis indicated that TAZ depletion was related to ferroptosis and glutathione metabolism. Our results demonstrated that TAZ promotes the malignant progression of BLCA cells both in vitro and in vivo. Moreover, TAZ enhances NRF2 transcriptional activity through interaction with NRF2. We further revealed that TAZ-TEAD4 regulates NRF2 expression at the transcriptional level. Additionally, NRF2 regulates TAZ transcription by binding to its promoter region, establishing a positive feedback loop between TAZ and NRF2 that sustains GPX4 activation and inhibits ferroptosis in BLCA. These insights provide novel molecular targets for therapeutic treatment in BLCA.

Circulating Biomarkers to Predict Post-Operative Cognitive Decline in Patients Undergoing Coronary Artery Bypass Grafting

Post-operative cognitive decline (POCD) is characterized by impairments in cognitive functions. Coronary artery bypass grafting (CABG) is associated with a high risk of POCD due to its impact on neuroinflammation and oxidative stress. In this study, we investigated the dynamics of neurotrophic, inflammatory, and oxidative stress markers in a cohort of post-CABG patients to identify potential biomarkers for POCD. Blood samples were collected at baseline (immediately post-surgery) and at 3-month follow-up. Expression levels of NRF2 and other regulators of oxidative stress (GST, GSS, HMOX1, CAT, HSP27, and LOX-1), inflammatory mediators (IL-6, IP-10, and NFκB), and neuroprotective factor (BDNF) were analyzed. Cognitive assessments were performed using RBANS, TMT, TIB and MMSE. POCD patients exhibited an initial upregulation of NRF2-related antioxidant genes, which failed to sustain at 3-months follow-up, leading to a decline in HMOX1, IP-10 and BDNF protein levels, along with increased LOX-1 protein level and NFκB expression, indicating persistent oxidative stress and inflammation. In contrast, non-POCD patients demonstrated a sustained increase in antioxidant and neuroprotective markers, suggesting a more effective compensatory response. ROC analysis identified HMOX1 and BDNF as significant predictors of POCD, with LOX-1 and IP-10 emerging as diagnostic markers at follow-up. In conclusion, our findings highlight the dynamic regulation of oxidative stress and inflammatory pathways in POCD, emphasizing the failure of sustained neuroprotection in affected patients. Further large-scale studies are necessary to validate these findings, and biomarker-based screening could facilitate early risk stratification and targeted interventions to improve cognitive outcomes after cardiac surgery.

Troglitazone as a Novel Nrf2 Activator to Attenuate Oxidative Stress and Exert Neuroprotection

Nuclear factor erythroid 2 related factor 2 (Nrf2) is closely associated with neurodegenerative diseases, and the Nrf2-mediated activation of antioxidant response elements (AREs) brings about validated strategies for treating neurodegenerative diseases. Here, we discovered that troglitazone, a clinical medication for diabetes mellitus, could serve as a Nrf2 activator to rescue neuronal damages both in vitro and in vivo. The mechanism of troglitazone action involves binding with kelch-like ECH-associated protein 1 (Keap1) and the activation of Nrf2. This process leads to the migration of Nrf2 to the cell nucleus and transactivates the AREs. Troglitazone exhibits significant alleviation of oxidative stress in PC12 cells induced by hydrogen peroxide or 6-hydroxydopamine (6-OHDA). In vivo studies indicate that troglitazone could rescue the motor activity and neurodevelopmental deficiency in zebrafish induced by 6-OHDA. Additionally, mass spectrometry imaging demonstrates that troglitazone could cross the zebrafish blood-brain barrier, supporting the application of troglitazone in treating neurodegenerative diseases. Overall, this work reveals that the novel Nrf2 activator troglitazone has potential therapeutic value for neurodegeneration and provides a foundation for its repurposing.

Carnosine alleviates oxidative stress to prevent cellular senescence by regulating Nrf2/HO-1 pathway: a promising anti-aging strategy for oral mucosa

Introduction: Aging is associated with significant metabolic alterations that contribute to cellular senescence and age-related functional decline. As individuals age, an increased prevalence of oral diseases and a gradual decline in oral functions are observed. However, the metabolic shifts underlying oral mucosal aging remain unexplored. Methods: We initially conducted histological analyses on the tongues from young (4-week-old), adult (4-month-old) and old (20-month-old) C57BL/6 mice to identify age-related alterations in the tongue mucosa. Subsequently, metabolomics analysis was performed to characterize metabolic profiles of mouse tongues across these age groups and identify metabolic biomarkers of oral mucosal aging. Then we validate the anti-senescence effect of carnosine and investigate its underlying mechanisms using a tert-butyl hydroperoxide (tBHP)-induced cellular senescence model in vitro. Finally, metabolomics analyses of human saliva and blood were conducted to explore associations between carnosine levels and systemic aging. Results: Compared to young and adult mice, we observed epithelial atrophy and an accumulation of senescent cells in the tongue mucosa of old mice. After that, we found significant differences in the metabolic profiles among the young, adult, and old mouse tongues. Carnosine was identified as a potential biomarker of oral mucosal aging, as its levels declined significantly with age. Consistently, carnosine synthase 1 (CARNS1) activity decreased, and carnosinase 2 (CNDP2) activity increased with age in the tongue mucosa. Furthermore, carnosine protected oral epithelial cells from tBHP-induced cellular senescence by reducing oxidative stress, mitigating DNA damage, and downregulating Nrf2/HO-1 pathway. In humans, salivary and blood carnosine levels also declined with age and were significantly associated with age-related diseases. Discussion: Our findings reveal dynamic metabolic reprogramming during natural oral mucosal aging and highlight the dual role of carnosine as both an aging biomarker and a therapeutic target for combating age-related mucosal degeneration. These insights support the development of novel carnosine-based interventions to preserve oral mucosal function, prevent age-related oral diseases, and improve oral health in the aging population, thereby advancing healthy aging.

TCE-mediated neuroprotection against rotenone-induced dopaminergic neuronal death in PD mice: insights into the Nrf-2/PINK1/Parkin-mitophagy pathway

Oxidative stress-induced mitochondrial dysfunction is implicated in the pathogenesis of Parkinson's disease (PD). In a previous study, we reported that an extract of T. cordifolia (TCE) possessed antioxidant and anti-apoptotic properties that improved mitochondrial function against rotenone-induced neurotoxicity. However, the underlying molecular mechanism remains unclear. In this study, we found that rotenone (ROT)-induced PD mice exhibited mitochondrial abnormalities, including defective mitophagy, mitochondrial reactive oxygen species (ROS) overexpression, and mitochondrial fragmentation, accompanied by reduced expression of Pink1 and Parkin and increased apoptosis. These changes were partially reversed following oral administration of TCE. Moreover, TCE restored the activity and translocation of NF-E2-related factor 2 (Nrf2) and upregulated the expression of antioxidant enzymes (SOD1, SOD2, GSH, and GSSH). Interestingly, ROT also activates mitophagy. Our results suggest that ROT toxicity can cause neuronal cell death through mitophagy-mediated signaling in PD mice. However, TCE reversed this activity by inhibiting autophagic protein (LC3B-II/LC3B-I) activation and increasing specific mitochondrial proteins (TOM20, Pink1, and Parkin). Our findings indicated that TCE provides neuroprotection against rotenone-induced toxicity in PD mice by stimulating endogenous antioxidant enzymes and inhibiting ROT-induced oxidative stress by potentiating the Nrf-2/Pink1/Parkin-mediated survival mechanism.

Maternal lactoferrin supplementation prevents mitochondrial and redox homeostasis dysfunction, and improves antioxidant defenses through Nrf2 and UCP2 signaling after neonatal hypoxia-ischemia

Neonatal hypoxia-ischemia (HI) is a major cause of mortality and neurological impairments in infants. Main HI-induced pathological mechanisms include mitochondrial dysfunction and oxidative stress due to insufficient oxygen and energetic substrates to the nervous cells. Bovine lactoferrin (Lf) has demonstrated neuroprotective effects in several experimental models of neonatal brain injury in rodents, however its mechanisms remain unclear. This study aimed to evaluate the early impact of maternal dietary supplementation with Lf on redox and hippocampal mitochondrial function following neonatal HI. From postnatal day 6 (PND6), pregnant Wistar rats were fed with a diet supplemented with Lf (1 g/kg) or with an isocaloric control diet until offspring euthanasia. At PND7, pups of both sexes were subjected to experimental HI through the occlusion of the right common carotid artery followed by 60 min of hypoxia (8 % oxygen). Lf prevented HI-induced increased levels of DCFH and lipoperoxidation in hippocampus. Furthermore, Lf enhanced antioxidant defenses including SOD, GPx, and GSH, counteracting HI-induced oxidative stress. HI injury altered the activities of enzymes in the mitochondrial respiratory chain and increased the mitochondrial membrane potential. Both effects were counteracted by Lf supplementation. Lactoferrin prevented oxidative stress and to restored mitochondrial function by upregulating Nrf2 and UCP2 expression following experimental HI. Our results show that even a shorter period of Lf delivery to rat pups is able to improve hippocampal response to neonatal hypoxia-ischemia, reversing initial mechanisms of damage in the cascade of HI injury.

RNA-Based Therapies for Neurodegenerative Diseases Targeting Pathogenic Proteins

Neurodegeneration is featured by the gradual stagnation of neuronal function and structure, leading to significant motor and cognitive impairments. The primary histopathological features underlying these conditions include the cumulation of pathological protein aggregates, chronic inflammation, and neuronal cell death. Alzheimer's disease (AD) and Parkinson's disease (PD) are prominent examples of neurodegenerative diseases (NDDs). As of 2023, over 65 million people worldwide are affected by AD and PD, with the prevalence of these conditions steadily increasing over time. Interestingly, there are no effective therapies available to halt or slow NDD progression. Most approved treatments are focused on symptom management and are often associated with substantial side effects. Given these limitations, the development of novel therapeutic approaches targeting the molecular mechanisms underlying these disorders is essential. Notably, RNA-based therapeutics have recently emerged as a potential therapeutic approach for managing various neurological diseases, offering the potential for innovative molecular interventions in NDD. In this review, we have discussed the pathogenic role of various protein aggregates in NDD and highlighted emerging RNA-based strategies aimed at targeting these pathological proteins.

Nrf2/Bach1 signaling axis: A promising multifaceted therapeutic strategy for Alzheimer's disease

Alzheimer's disease (AD) is the most prevalent form of dementia, which continues to elude effective treatment despite decades of research and numerous clinical trials. While existing therapeutic strategies have primarily targeted neuropathological hallmarks such as amyloid plaques and tau tangles, they have failed to halt disease progression, leaving patients with limited options. This persistent failure reveals a critical gap in our understanding of AD and calls for a fresh perspective - one that goes beyond the traditional targets and dives deeper into the fundamental cellular processes that drive neurodegeneration. Recent advances in molecular biology underscore the significance of nuclear factor E2-related factor 2 (Nrf2), often termed the "guardian of redox homeostasis," in the pathophysiology of AD. Nrf2 orchestrates cellular responses to oxidative stress and neuroinflammation - two interlinked pathological features of AD. In the brains of AD patients, Nrf2 activity is diminished, weakening the brain's ability to counteract oxidative damage. Additionally, the BTB and CNC homology 1 (Bach1) protein, a transcriptional repressor of Nrf2, has emerged as a potential therapeutic target. Here, we review the current landscape of clinical trials in AD and identify the limitations of the conventional approaches. We then explore the prospects of a novel approach that combines Nrf2 activation with Bach1 inhibition to achieve a multipronged defense against oxidative stress, neuroinflammation, and other molecular culprits driving AD. This innovative strategy holds promise for synergistically modulating multiple neuroprotective pathways to advance AD treatment.

A review study on the effect of zinc on oxidative stress-related neurological disorders

Zinc plays a main role in maintaining homeostasis and neuronal function. Disorders in zinc homeostasis are connected to several neurological disorders due to inflammation and oxidative stress. This review explores the effect of zinc on neurological disorders through the Nrf2 signaling pathway. The Nrf2 pathway modulates oxidative stress and regulates antioxidant defenses, which is critical in the pathogenesis of neurological diseases. We provide an overview of in vivo and in vitro studies illustrating zinc's neuroprotective effects in conditions such as Alzheimer's disease, spinal cord injury, and stroke. The dual role of zinc, where both excess and deficiency can be detrimental, is highlighted, emphasizing the need for optimal zinc levels. Limitations of current research and future perspectives are also discussed.

Synaptic plasticity and neuroprotection: The molecular impact of flavonoids on neurodegenerative disease progression

Flavonoids are a broad family of polyphenolic chemicals that are present in a wide variety of fruits, vegetables, and medicinal plants. Because of their neuroprotective qualities, flavonoids have attracted a lot of interest. The potential of flavonoids to control synaptic plasticity-a crucial process underlying memory, learning, and cognitive function-is becoming more and more clear. Dysregulation of synaptic plasticity is a feature of neurodegenerative diseases such as amyotrophic lateral sclerosis (0.4 %), Parkinson's (1-2 %), Alzheimer's (5-7 %), and Huntington's ((0.2 %)). This review discusses the molecular mechanisms via which flavonoids influence synaptic plasticity as well as their therapeutic potential in neurodegenerative diseases. Flavonoids modulate key signaling pathways such as MAPK/ERK and PI3K/Akt/mTOR to support neuroprotection, synaptic plasticity, and neuronal health, while also influencing neurotrophic factors (BDNF, NGF) and their receptors (TrkB, TrkA). They regulate neurotransmitter receptors like GABA, AMPA, and NMDA to balance excitatory and inhibitory transmission, and exert antioxidant effects via the Nrf2-ARE pathway and anti-inflammatory actions by inhibiting NF-κB signaling, highlighting their potential for treating neurodegenerative diseases. These varied reactions support the preservation of synapse function and neuronal integrity in the face of neurodegenerative insults. Flavonoids can reduce the symptoms of neurodegeneration, prevent synaptic loss, and enhance cognitive function, according to experimental studies. However, there are still obstacles to using these findings in clinical settings, such as limited bioavailability and the need for consistent dose. The focus of future research should be on improving flavonoid delivery systems and combining them with conventional medications.

Neuroprotective effect of Cistanche deserticola glycosides in MPTP-Induced Parkinson's disease mouse model involves Nrf2 activation

Parkinson's Disease (PD) a progressive neurodegenerative disorder is attributed to dopaminergic neuronal cell loss in the mid-brain substantia nigra pars compacta. A major risk factors associated with PD development is presence of excess oxidative stress. Previously, glycosides derived from Cistanche deserticola were reported to play a key role in counteracting PD; however, the underlying mechanisms remain to be determined. This study aimed to examine the neuroprotective effect attributed to glycosides derived from C. deserticola in PD model in mice. The model of PD was established by injecting intraperitoneally 1-methyl-4-penyl-1,2,3,6-tetrahydropyridine (MPTP). Rotarod and pole tests determined neurological behavior. The following immunohistochemistry, and metabolic biomarkers were measured mid-brain substantia nigra: (1) number of dopaminergic neuronal cell using immunohistochemistry (2) oxidative stress as evidenced by activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) as well levels of malondialdehyde (MDA), (3) inflammatory infiltration as measured by levels of IL-1β and TNF-α (4) by Western blot involvement of protein expression levels of Nrf2 signaling pathway. Data demonstrated that C. deserticola glycosides treatment improved behavioral performance, increased number of dopaminergic neurons, reduced cytokine levels of IL-1β and TNF-α accompanied by enhanced antioxidant activity in PD mice. These observations were associated with activation of Nrf2 signaling pathway. Data suggest that C. deserticola glycosides may thus be considered as an alternative compound for PD treatment.

Lateral hypothalamic area high-frequency deep brain stimulation rescues memory decline in aged rat: behavioral, molecular, and electrophysiological study

To examine the effect of DBS of the lateral hypothalamic area (LHA) on age-related memory changes, neuronal firing from CA1, oxidative stress, and the expression of Hsp70, BDNF, and synaptophysin. 72 male rats were randomly allocated into 6 equal groups: a) normal young group (8 W), b) sham young group, c) DBS young group, d) normal old group (24 months), e) sham old group and f) DBS old group. Memory tests (passive avoidance and Y maze), oxidative stress markers (MDA, catalase, and GSH) and expression of Nrf2, HO-1, Hsp70, BDNF, and synaptophysin were measured by the end of the experiment. Also, in vivo recording of the neuronal firing of the CA1 region in the hippocampus was done. Old rats show significant decline in memories, antioxidant genes (Nrf2 and HO-1), antioxidants (GSH and catalase), Hsp70, BDNF, and synaptophysin with significant increase in MDA in hippocampus (p < 0.05) and DBS for LHA caused a significant improvement in memories in old rats, with significant rise in fast gamma and theta waves in CA1 region in old rats (p < 0.05). This was associated with a significant increase in antioxidants (GSH and CAT), antioxidant genes (Nrf2, HO-1), Hsp70, BDNF, and synaptophysin with significant reduction in MDA in hippocampus (p < 0.05). DBS for LHA ameliorates the age-induced memory decline. This might be due to increase in fast gamma in CA1, attenuation of oxidative stress, upregulation of Nrf2, HO-1, Hsp70, BDNF, and synaptophysin in the hippocampus.

Mesenchymal stem cell exosome therapy: current research status in the treatment of neurodegenerative diseases and the possibility of reversing normal brain aging

With the exacerbation of the aging population trend, a series of neurodegenerative diseases caused by brain aging have become increasingly common, significantly impacting the daily lives of the elderly and imposing heavier burdens on nations and societies. Brain aging is a complex process involving multiple mechanisms, including oxidative stress, apoptosis of damaged neuronal cells, chronic inflammation, and mitochondrial dysfunction, and research into new therapeutic strategies to delay brain aging has gradually become a research focus in recent years. Mesenchymal stem cells (MSCs) have been widely used in cell therapy due to their functions such as antioxidative stress, anti-inflammation, and tissue regeneration. However, accompanying safety issues such as immune rejection, tumor development, and pulmonary embolism cannot be avoided. Studies have shown that using exosome derived from mesenchymal stem cells (MSC-Exo) for the treatment of neurodegenerative diseases is a safe and effective method. It not only has the therapeutic effects of stem cells but also avoids the risks associated with cell therapy. Therefore, exploring new therapeutic strategies to delay normal brain aging from the mechanism of MSC-Exo in the treatment of neurodegenerative diseases is feasible. This review summarizes the characteristics of MSC-Exo and their clinical progress in the treatment of neurodegenerative diseases, aiming to explore the possibility and potential mechanisms of MSC-Exo in reversing brain aging.

Nrf2 activator tertiary butylhydroquinone enhances neural stem cell differentiation and implantation in Alzheimer's disease by boosting mitochondrial function

AIMS

To investigate the effects of Nrf2 agonist tertiary butylhydroquinone (TBHQ)-stimulated neural stem cells (NSCs) transplantation (NSC(TBHQ)) on neuronal damage and cognitive deficits in an AD model and its underlying principles.

METHODS

BHQ-treated NSCs were examined with or without Aβ1-42 to investigate the effects of TBHQ on the proliferation and differentiation functions. The mitophagy inhibitor Cyclosporine A (CSA) was used to explore the regulation of mitophagy by TBHQ. The no-, ethanol-, and TBHQ-treated NSCs were transplanted into the bilateral hippocampal region of model mice to explore the effects of NSC(TBHQ) on neuronal, cognitive, and mitochondrial functional impairments in mice.

RESULTS

TBHQ reversed the Aβ1-42-caused inhibition on NSC proliferation and differentiation, as well as on levels of mitochondrial membrane potential, adenosine triphosphate (ATP), and mitochondrial fusion-associated proteins. TBHQ alleviated the Aβ1-42-induced increase in apoptosis, mitochondrial damage, mitochondria-derived reactive oxygen species (mtROS), and mitochondrial fission-related proteins. TBHQ activated the Parkin, Beclin, LC3II/I, and COXIV expression, while inhibiting the p62 expression. CSA reversed the effects of TBHQ on NSC proliferation and differentiation. After NSC(TBHQ) transplantation, it not only further extended the dwell time in the target quadrant and shorten the time and distance for finding the hidden platform, but also further decreased the Aβ and p-Tau/Tau levels, while increasing the expression of NeuN. The effects of NSC(TBHQ) transplantation on mitochondrial function were consistent with the in vitro experiments.

CONCLUSIONS

The study shows that NSC(TBHQ) intensifies the beneficial impact of NSCs transplantation on cognitive impairment and neuronal damage in AD models, likely due to TBHQ's role in promoting NSCs growth and differentiation via mitophagy, thus laying a theoretical foundation for improving NSCs transplantation for AD.

Resveratrol-Enhanced Human Neural Stem Cell-Derived Exosomes Mitigate MPP+-Induced Neurotoxicity Through Activation of AMPK and Nrf2 Pathways and Inhibition of the NLRP3 Inflammasome in SH-SY5Y Cells

Parkinson's disease (PD) is a progressive neurodegenerative disorder primarily characterized by the loss of dopaminergic neurons in the substantia nigra. Mitochondrial dysfunction, oxidative stress, and neuroinflammation are recognized as critical pathological mechanisms driving neurodegeneration in PD. Exosome (Exo)-based therapies, particularly those derived from human neural stem cells (hNSCs), offer promising neuroprotective effects due to their ability to transfer bioactive molecules that modulate cellular processes. Resveratrol (RES), a polyphenolic compound with potent antioxidant and anti-inflammatory properties, has been shown to enhance the therapeutic potential of stem cell (SC)-derived Exos. This study investigated the neuroprotective effects of RES-treated hNSCs-derived Exos (RES-hNSCs-Exos) on SH-SY5Y cells exposed to 1-methyl-4-phenylpyridinium (MPP+), a neurotoxin commonly used to model Parkinsonian neurotoxicity. Treating SH-SY5Y cells with MPP+ led to significant reductions in cell viability, mitochondrial dysfunction, increased oxidative stress, and the activation of inflammatory pathways. Treatment with RES-hNSCs-Exos rescued SH-SY5Y cells from MPP+-induced toxicity by improving cell viability, enhancing ATP production, increasing mitochondrial biogenesis, and reducing reactive oxygen species (ROS) generation. The findings also demonstrated the increased expression of essential genes involved in mitochondrial biogenesis, such as PGC1α, NRF1, and Tfam, indicating improved mitochondrial function in the presence of RES-hNSCs-Exos. Further analysis revealed that these protective effects were mediated by activating the AMP-activated protein kinase (AMPK) and Nrf2 signaling pathways, which promoted mitochondrial health and reduced oxidative stress. Moreover, RES-hNSCs-Exos treatment suppressed neuroinflammation by downregulating NLRP3 inflammasome activation and reducing the secretion of pro-inflammatory cytokines IL-1β and IL-18. In conclusion, the results suggest that RES-hNSCs-Exos exhibit potent neuroprotective effects against MPP+-induced neurotoxicity by enhancing mitochondrial function, reducing oxidative stress, and inhibiting neuroinflammation. These findings highlight the potential of hNSCs-Exos as a novel therapeutic strategy for neurodegenerative diseases like PD, with RES as a valuable enhancer of Exos efficacy.

Electroacupuncture ameliorated locomotor symptoms in MPTP-induced mice model of Parkinson's disease by regulating autophagy via Nrf2 signaling

Parkinson's disease (PD) is a prevalent and challenging neurodegenerative disorder, and may involve impaired autophagy. Nuclear factor erythroid-2-related factor 2 (Nrf2) is crucial for regulating autophagy-related genes and maintaining cellular homeostasis. Electroacupuncture (EA), a complementary and alternative therapy for PD, has gained widespread clinical application. In this study, we investigate whether EA at Baihui (GV20) and Taichong (LR3) acupoints modulates autophagy through the Nrf2 pathway, providing neuroprotection in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice. Using wild-type and Nrf2 knockout (KO) mice, we examined EA's effects on dopaminergic neuron survival, α-synuclein expression, motor function and the underlying mechanisms. Results showed that EA treatment significantly reduced dopaminergic neuron loss and α-synuclein expression, and improved motor deficits while restoring autophagy, as evidenced by increased autophagy markers (Atg7, LC3II) and decreased p62 levels. Transmission electron microscopy confirmed a rise in autophagosomes and lysosomes in the MPTP + EA group. EA also enhanced nuclear Nrf2 expression and activated Nrf2 signaling. Importantly, Nrf2 KO mice did not exhibit neuroprotection or increased autophagy-related proteins following EA treatment. In conclusion, our research demonstrated that EA ameliorated defective autophagy and activated the Nrf2 signaling pathway, which collectively contribute to its neuroprotective effects against MPTP-induced neurotoxicity.NEW & NOTEWORTHY In this study, we explored the potential mechanism of electroacupuncture (EA) therapy at the GV20 and LR3 acupoints of Parkinson's disease (PD). We demonstrated EA therapy's neuroprotective effect on PD, through ameliorating defective autophagy and activating the nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway whereas the regulation of EA on autophagy was absent in Nrf2 knockout (KO) mice. Our study not only provides new insights into the therapeutic mechanisms of EA but also suggests a promising strategy for PD treatment.

Oxidative stress and mitochondrial impairment: Key drivers in neurodegenerative disorders

Mitochondrial dysfunction and oxidative stress are critical factors in the pathogenesis of neurodegenerative diseases. The complex interplay between these factors exacerbates neuronal damage and accelerates disease progression. In neurodegenerative diseases, mitochondrial dysfunction impairs ATP production and promotes the generation of reactive oxygen species (ROS). The accumulation of ROS further damages mitochondrial DNA, proteins, and lipids, creating a vicious cycle of oxidative stress and mitochondrial impairment. This review aims to elucidate the mechanisms by which mitochondrial dysfunction and oxidative stress lead to neurodegeneration, and to highlight potential therapeutic targets to mitigate their harmful effects.

WuYou decoction effectively reduces neuronal damage, synaptic dysfunction, and Aβ production in rats exposed to chronic sleep deprivation by modulating the Aβ-related enzymes and SIRT1/Nrf2/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic sleep deprivation (CSD) can result in neuronal damage, synaptic dysfunction, Aβ production, neuroinflammation, and ultimately cognitive deterioration. WuYou Decoction (WYD), a contemporary prescription, has shown promise in enhancing sleep quality and cognitive performance in individuals with insomnia. However, the specific molecular mechanisms responsible for the neuroprotective effects of WYD on CSD remain incompletely understood.

AIM OF THE STUDY

This study aimed to investigate the neuroprotective effects of WYD on the CSD model and its molecular mechanism.

MATERIALS AND METHODS

UHPLC-MS/MS analysis was utilized to analyze the active ingredients of WYD extract. The study employed the multi-platform water environment method to establish the CSD model in rats. Subsequent to treatment with varying doses of WYD in CSD rats, cognitive function and pathological alterations in hippocampus and cortex, including neuronal damage, synaptic dysfunction, Aβ production, and neuroinflammation, were evaluated through a combination of Morris Water Maze test, HE staining, Nissl staining, Golgi-Cox staining, Transmission electron microscope, ELISA, Immunohistochemistry staining, Immunofluorescence staining and Western blot.

RESULTS

UHPLC-MS/MS analysis revealed a total of 99 active ingredients were identified from the WYD extract. The administration of WYD exhibited a mitigation of cognitive decline in the model of CSD, as evidenced by increased neuron count in the hippocampus and cortex, and improved density and length of dendritic spines in these brain regions. Furthermore, WYD was found to suppress the Aβ production, and inhibit the expression of BACE1, PS1, GFAP, IBA1, IL-1β, IL-6, TNF-α, phosphorylated IκBα (Ser32) and phosphorylated NF-κB p65 (Ser536) in the hippocampus and cortex, while also increasing the levels of PSD95, SYN1, ADAM10, IDE, SIRT1 and Nrf2.

CONCLUSIONS

WYD exhibits neuroprotective properties in CSD, potentially through modulation of the Aβ-related enzymes and SIRT1/Nrf2/NF-κB pathway.

Integrating network pharmacology with molecular docking and dynamics to uncover therapeutic targets and signaling mechanisms of vitamin D3 in Parkinson's disease

Parkinson's disease (PD) is a chronic neurodegenerative disorder marked by dopaminergic neuron degeneration in the substantia nigra. Emerging evidence suggests vitamin D3 (VD) plays a therapeutic role in PD, but its precise molecular mechanisms remain unclear. This study employed network pharmacology and bioinformatics to identify VD's hub targets and related pathways. We identified 24 VD's anti-PD targets, with estrogen receptor 1, estrogen receptor 2 (ESR2), sodium-dependent norepinephrine transporter, and insulin-like growth factor 1 receptor emerging as hub targets. Gene enrichment analysis elucidated that VD's anti-PD mechanism is closely related to the estrogen signaling pathway. Additionally, two-sample Mendelian randomization suggested a positive causal relationship between 25-hydroxyvitamin D and estrogen levels in vivo. To verify the interaction between VD and the hub drug targets, we performed molecular docking and kinetic simulations, finding the strongest interaction between VD and ESR2. Further Mendelian randomization analysis of drug targets confirmed the significant effect of the ESR2 drug target on PD risk. Single-cell nuclear sequencing of dopaminergic neurons, coupled with GSEA analysis, indicated that ESR2 activation upregulates the neuroactive ligand-receptor interaction signaling pathway and downregulates the Parkinson's disease pathway, thereby exerting a neuroprotective effect. In summary, our findings suggest that VD supplementation can not only elevate estradiol levels in humans but also directly activate ESR2, thereby modulating the estrogen signaling pathway in PD patients and providing neuroprotection. These predictive biological targets offer promising avenues for future clinical applications in Parkinson's disease treatment.

FOXA2 regulates endoplasmic reticulum stress, oxidative stress, and apoptosis in spermatogonial cells by the Nrf2 pathway under hypoxic conditions

Hypoxia-caused spermatogenesis impairment may contribute to male infertility. FOXA2 has been found to be abundant in spermatogonial stem cells and critical for spermatogenesis. Here we aimed to explore the roles of FOXA2 in regulating spermatogonial cells against hypoxia stimulation. Our results showed that FOXA2 expression was downregulated in hypoxia-stimulated spermatogonial cells. Overexpression of FOXA2 prevented hypoxia-induced endoplasmic reticulum (ER) stress with decreased expression levels of associated markers including GRP78, CHOP, and ATF-4. FOXA2 overexpression caused a decrease in MDA content and an increase in activities of SOD, CAT, and GSH-Px in spermatogonial cells under hypoxic conditions, implying its inhibitory effect on oxidative stress. Besides, cell apoptosis under hypoxic conditions was also prevented by FOXA2 overexpression, as shown by reduced apoptotic rate and caspase-3 activity. Moreover, we found that hypoxia stimulation inactivated the Nrf2 pathway, which could be prevented by FOXA2 overexpression. Nrf2 knockdown attenuated the effects of FOXA2 overexpression on hypoxia-induced ER stress, oxidative stress, and apoptosis in spermatogonial cells. In conclusion, FOXA2 exerted protective effects on spermatogonial cells against hypoxia-induced ER stress, oxidative stress, and apoptosis via regulating Nrf2/HO-1 signaling. These findings suggested that FOXA2 might be a therapeutic target for treating hypoxia-induced spermatogenesis impairment.

SENP1 inhibits aerobic glycolysis in Aβ1-42-incubated astrocytes by promoting PUM2 deSUMOylation

Alzheimer's disease (AD), the most prevalent form of dementia in the elderly, involves critical changes such as reduced aerobic glycolysis in astrocytes and increased neuronal apoptosis, both of which are significant in the disease's pathology. In our study, astrocytes treated with amyloid β1-42 (Aβ1-42) to simulate AD conditions exhibited upregulated expressions of small ubiquitin-like modifier (SUMO)-specific protease 1 (SENP1) and Pumilio RNA Binding Family Member 2 (PUM2), alongside decreased levels of Nuclear factor erythroid 2-related factor 2 (NRF2). SENP1 is notably the most upregulated SUMOylation enzyme in Aβ1-42-exposed astrocytes. Functional assays including Ni2+-Nitrilotriacetic acid (NTA) agarose bead pull-down and co-immunoprecipitation (Co-IP) confirmed SENP1's role in actively deSUMOylating PUM2, thereby enhancing its stability and expression. The interaction between PUM2 and the 3' untranslated region (3'UTR) of NRF2 mRNA reduces NRF2 levels, subsequently diminishing the transcriptional activation of critical glycolytic enzymes, Hexokinase 1 (HK1) and Glucose Transporter 1 (GLUT1). These changes contribute to the observed reduction in glycolytic function in astrocytes, exacerbating neuronal apoptosis. Targeted interventions, such as knockdown of Senp1 or Pum2 or overexpression of NRF2 in APPswe/PSEN1dE9 (APP/PS1) transgenic mice, effectively increased HK1 and GLUT1 levels, decreased apoptosis, and alleviated cognitive impairment. These findings highlight the important roles of the SENP1/PUM2/NRF2 pathway in influencing glucose metabolism in astrocytes, presenting new potential therapeutic targets for AD.

The SIRT-1/Nrf2/HO-1 axis: Guardians of neuronal health in neurological disorders

SIRT1 (Sirtuin 1) is a NAD+-dependent deacetylase that functions through nucleoplasmic transfer and is present in nearly all mammalian tissues. SIRT1 is believed to deacetylate its protein substrates, resulting in neuroprotective actions, including reduced oxidative stress and inflammation, increased autophagy, increased nerve growth factors, and preserved neuronal integrity in aging or neurological disease. Nrf2 is a transcription factor that regulates the genes responsible for oxidative stress response and substance detoxification. The activation of Nrf2 guards cells against oxidative damage, inflammation, and carcinogenic stimuli. Several neurological abnormalities and inflammatory disorders have been associated with variations in Nrf2 activation caused by either pharmacological or genetic factors. Recent evidence indicates that Nrf2 is at the center of a complex cellular regulatory network, establishing it as a transcription factor with genuine pleiotropy. HO-1 is most likely a component of a defense mechanism in cells under stress, as it provides negative feedback for cell activation and mediator synthesis. This mediator is upregulated by Nrf2, nitric oxide (NO), and other factors in various inflammatory states. HO-1 or its metabolites, such as CO, may mitigate inflammation by modulating signal transduction pathways. Neurological diseases may be effectively treated by modulating the activity of HO-1. Multiple studies have demonstrated that SIRT1 and Nrf2 share an important connection. SIRT1 enhances Nrf2, activates HO-1, protects against oxidative injury, and decreases neuronal death. This has been associated with numerous neurodegenerative and neuropsychiatric disorders. Therefore, activating the SIRT1/Nrf2/HO-1 pathway may help treat various neurological disorders. This review focuses on the current understanding of the SIRT1 and Nrf2/HO-1 neuroprotective processes and the potential therapeutic applications of their target activators in neurodegenerative and neuropsychiatric disorders.

Electroacupuncture attenuates ferroptosis by promoting Nrf2 nuclear translocation and activating Nrf2/SLC7A11/GPX4 pathway in ischemic stroke

OBJECTIVE

Electroacupuncture has been shown to play a neuroprotective role following ischemic stroke, but the underlying mechanism remains poorly understood. Ferroptosis has been shown to play a key role in the injury process. In the present study, we wanted to explore whether electroacupuncture could inhibit ferroptosis by promoting nuclear factor erythroid-2-related factor 2 (Nrf2) nuclear translocation.

METHODS

The ischemic stroke model was established by middle cerebral artery occlusion/reperfusion (MCAO/R) in adult rats. These rats have been randomly divided into the EA + MCAO/R group, the MCAO/R group, the EA + MCAO/R + Brusatol group (the inhibitor of Nrf2), and the EA + MCAO/R + DMSO group, and the Sham group. The EA + MCAO/R group, EA + MCAO/R + Brusatol group, and the EA + MCAO/R + DMSO group received EA intervention 24 h after modeling for 7 consecutive days. The behavioral function was evaluated by Neurologic severity score (NSS), Garcia score, Foot-fault Test, and Rotarod Test. The infarct volume was detected by TTC staining, and the neuronal damage was observed by Nissl staining. The levels of Fe2+, reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured by ELISA. The immunofluorescence and Western blotting were used to detect the expression of Total Nrf2, p-Nrf2, Nuclear Nrf2, and Cytoplasmic Nrf2, and the essential ferroptosis proteins, including glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11) and ferritin heavy chain 1 (FTH1). The mitochondria were observed by transmission electron microscopy (TEM).

RESULTS

Electroacupuncture improved neurological deficits in rats model of MCAO/R, decreased the brain infarct volume, alleviated neuronal damage, inhibited the Fe2+, ROS, and MDA accumulation, increased SOD levels, increased the expression of GPX4, SLC7A11 and FTH1, and rescued injured mitochondria. Especially, we found that the electroacupuncture up-regulated the expression of Nrf2, and promoted phosphorylation of Nrf2 and nuclear translocation, However, Nrf2 inhibitor Brusatol reversed the neuroprotective effect of electroacupuncture.

CONCLUSION

Electroacupuncture can alleviate cerebral I/R injury-induced ferroptosis by promoting Nrf2 nuclear translocation. It is expected that these data will provide novel insights into the mechanisms of electroacupuncture protecting against cerebral I/R injury and potential targets underlying ferroptosis in the stroke.

Carvacrol acetate activated Nrf2 modulates mitophagy for the treatment of neurocyte oxidative stress induced by chlorpyrifos

This study explored the protective effect and potential mechanism of carvacrol acetate (CAA) on the oxidation of chlorpyrifos (CPF). A model of oxidative stimulus damage was established in Sprague-Dawley rats by subcutaneous injection of the CPF poison. PC12 cells were used to construct an oxidative injury model using CPF, and the protective effects and mechanism of action of CAA against CPF-induced oxidative damage were explored in vitro. The key role of Nuclear factor erythroid-2-related factor 2 (Nrf2) in alleviating CPF-induced damage via CAA was further confirmed by administering Nrf2 inhibitors to PC12 cells. Administration of CAA significantly enhanced the locomotor ability of the rats, alleviated neuronal pathological alterations, and increased the number of Nissl bodies, while increasing autophagic bodies. In vitro, CAA promoted cell survival and augmented the mitochondrial membrane potential. It decreased both intra- and extracellular levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), while markedly elevating mitochondrial DNA (mtDNA) copy number. Moreover, PC12 cells treated with Nrf2 inhibitors failed to exhibit any improvement in survival rate when treated with CAA after a toxic insult. Furthermore, ROS and MDA levels were not significantly reduced, SOD enzyme activity did not increase, and mitochondrial membrane potential and mtDNA copy number did not improve. Western blot analysis showed that the expression of Tfam, Beclin1, and LC3II/LC3I proteins in the CAA group decreased significantly after Nrf2 inhibition. These findings suggest that CAA modulates mitochondrial function and autophagy by regulating the Nrf2 signalling pathway to mitigate the toxic damage. Finally, the effect of the autophagy inhibitor, 3-MA, on PC12 cells suggests that CAA promotes mitophagy by participating in the Nrf2 pathway, thereby preventing CPF-induced oxidative stress damage.

Role of miRNA regulation in IGFBP-2 overexpression and neuronal ferroptosis: Insights into the Nrf2/SLC7A11/GPX4 pathway in Alzheimer's disease

Alzheimer's disease (AD) is a common neurodegenerative disease with pathological features including amyloid plaque deposits and neurofibrillary tangles. In this study, the expressions of miRNA, IGFBP-2 and neuronal ferritin were detected by qPCR, Western blot and immunohistochemistry. The regulatory effects of miRNA on IGFBP-2 and neuronal ferritin were further verified by intervention experiments with miRNA mimics and inhibitors. Double luciferase reporter gene assay and RNA immunoprecipitation were used to investigate the interaction between miRNA and target genes. Finally, the effect of miRNA on Nrf2/SLC7A11/GPX4 pathway was evaluated by antioxidant enzyme activity and oxidative stress marker detection. The overexpression of IGFBP-2 was found to be significantly increased with the deposition of neuronal ferritin. Expression levels of specific mirnas were significantly down-regulated in AD models and negatively correlated with IGFBP-2 and neuronal ferritin expression. Intervention experiments with miRNA mimics and inhibitors have confirmed that these mirnas can regulate the expression of IGFBP-2 and neuronal ferritin. Further studies revealed that these mirnas affect antioxidant enzyme activity and oxidative stress levels by targeting key genes in the Nrf2/SLC7A11/GPX4 pathway, thereby regulating the deposition of neuronal ferritin.

Research progress of small-molecule natural medicines for the treatment of ischemic stroke

Stroke is the second leading cause of disability and mortality worldwide, imposing a substantial socioeconomic burden on individuals and healthcare systems. Annually, approximately 14 million people experience stroke, with ischemic stroke comprising nearly 85% of cases, of which 10% to 20% involve large vessel occlusions. Currently, recombinant tissue plasminogen activator (tPA) remains the only approved pharmacological intervention. However, its utility is limited due to a narrow therapeutic window and low recanalization rates, making it applicable to only a minority of patients. Therefore, there is an urgent need for novel therapeutic strategies, including pharmacological advancements and combinatory treatments. Small-molecule natural medicines, particularly those derived from traditional Chinese herbs, have demonstrated significant therapeutic potential in ischemic stroke management. These compounds exert multiple neuroprotective effects, such as antioxidation, anti-inflammatory action, and inhibition of apoptosis, all of which are critical in mitigating stroke-induced cerebral damage. This review comprehensively examines the pathophysiology of acute ischemic stroke (AIS) and highlights the recent progress in the development of small-molecule natural medicines as promising therapeutic agents for cerebral ischemic stroke.

Adverse Effects of Nrf2 in Different Organs and the Related Diseases

Significance: Under normal physiological conditions, Nrf2 undergoes ubiquitination and subsequent proteasome degradation to maintain its basal activity. Oxidative stress can trigger Nrf2 activation, prompting its translocation to the nucleus where it functions as a transcription factor, activating various antioxidant pathways, and conferring antioxidant properties. Recent Advances: While extensive research has shown Nrf2's protective role in various diseases, emerging evidence suggests that Nrf2 activation can also produce harmful effects. Critical Issues: This review examines the pathological contexts in which Nrf2 assumes different roles, emphasizing the mechanisms and conditions that result in adverse outcomes. Future Directions: Persistent Nrf2 activation may have deleterious consequences, necessitating further investigation into the specific conditions and mechanisms through which Nrf2 exerts its harmful effects. Antioxid. Redox Signal. 00, 000-000.

State-of-the-Art Nrf2 Inhibitors: Therapeutic Opportunities in Non-Cancer Diseases

Nuclear factor erythroid 2-related factor (Nrf2) is a cytoprotective transcription factor that induces the transcription of genes responsible for the cell's response to oxidative stress. While Nrf2 activation has led to the development of clinically relevant therapeutics, the oncogenic role of Nrf2 in the proliferation of cancer cells has underscored the complex nature of Nrf2 and the necessity for the development of Nrf2 inhibitors. Although the application of Nrf2 inhibitors appears limited as anticancer agents, recent studies have begun to pinpoint the impairment of autophagy in diseases as a cellular marker that shifts Nrf2 from a protective to a deleterious state. Therefore, the cytoplasmic accumulation of Nrf2 can lead to the accumulation of lipid hydroperoxides and, ultimately, to ferroptosis. However, some studies aimed at elucidating the role of Nrf2 in non-cancer diseases have yielded conflicting results, attributed to differences in approaches used to inhibit or activate Nrf2, as well as variations in in vitro and/or in vivo disease models. Overall, these results highlight the necessity for a deeper evaluation of Nrf2's role in diseases, especially chronic diseases. In this review, we discuss diseases where Nrf2 inhibition holds potential for beneficial therapeutic effects and summarize recently reported Nrf2 inhibitors exploiting medicinal chemistry approaches suitable for targeting transcription factors like Nrf2.

Supplementing ageing male laying breeders with lycopene alleviates oxidative stress in testis and improves testosterone secretion

BACKGROUND

Reproductive performance is a crucial aspect of poultry production and is carefully controlled by endocrine, paracrine, and autocrine factors. This study aimed to investigate the effect of lycopene on testosterone synthesis in Leydig cells of laying breeder roosters, clarify the mechanism of lycopene improving Leydig cells function and promoting testosterone production, and explore the role of related signal transduction pathways in testosterone synthesis.

RESULTS

A total of 96 healthy 55-week-old breeding roosters were randomly assigned to one of five dietary treatments. They were provided with a corn-soybean meal-based diet containing different levels of lycopene: 0 mg/kg (control), 50 mg/kg, 100 mg/kg, or 200 mg/kg. The experiment lasted for 6 weeks. With the increase in lycopene levels, the testosterone content in the plasma was significantly higher than in the control group. Testicular Leydig cells were isolated and cultured from fresh testicular tissue of 45-wk-old to 60-wk-old breeding roosters. Various doses of lycopene were administered to Leydig cells, and subsequently, cells were collected for the detection of cell viability and testosterone content. The optimal concentration of lycopene to be added was determined, and changes in mRNA expression and protein levels of key proteins involved in testosterone synthesis were investigated. The results showed that lycopene treatment significantly increased testosterone secretion, mRNA expression, and protein levels of steroid-producing enzymes. Cells were collected to measure the activity of antioxidant enzymes, the mRNA transcription level of apoptotic factors, and the protein expression of apoptotic factors after treatment with lycopene. The results showed that lycopene significantly increased the activities of antioxidant enzymes, and the ability to inhibit oxygen radicals, and decreased the content of malondialdehyde. Apoptosis was inhibited by regulating the expression of apoptosis-inducing and anti-apoptosis factors. After that, the MAPK signaling pathway and downstream SF-1, Nrf2 gene, and protein expression levels were detected. The results showed that lycopene treatment significantly increased the gene and protein expression of JNK, SF-1, and Nrf2, and significantly decreased the gene and protein expression of p38.

CONCLUSIONS

Lycopene treatment could promote testosterone synthesis of testicular Leydig cells by activating MAPK-SF-1 (increasing steroid-producing enzyme level) and MAPK-Nrf2 pathways (resisting oxidative damage).

The role of sirtuin 1 in ageing and neurodegenerative disease: A molecular perspective

Sirtuin 1 (SIRT1), an NAD+-dependent deacetylase, has emerged as a key regulator of cellular processes linked to ageing and neurodegeneration. SIRT1 modulates various signalling pathways, including those involved in autophagy, oxidative stress, and mitochondrial function, which are critical in the pathogenesis of neurodegenerative diseases. This review explores the therapeutic potential of SIRT1 in several neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and Amyotrophic Lateral Sclerosis (ALS). Preclinical studies have demonstrated that SIRT1 activators, such as resveratrol, SRT1720, and SRT2104, can alleviate disease symptoms by reducing oxidative stress, enhancing autophagic flux, and promoting neuronal survival. Ongoing clinical trials are evaluating the efficacy of these SIRT1 activators, providing hope for future therapeutic strategies targeting SIRT1 in neurodegenerative diseases. This review explores the role of SIRT1 in ageing and neurodegenerative diseases, with a particular focus on its molecular mechanisms, therapeutic potential, and clinical applications.

Nrf2: A critical participant in regulation of apoptosis, ferroptosis, and autophagy in gastric cancer

Nuclear factor erythroid 2-related factor-2 (Nrf2) is a specific transcription factor that maintains redox homeostasis by regulating the expression of anti-oxidative stress-related genes. Hyperactivation of Nrf2 is involved in tumor progression and is associated with chemoresistance in a large number of solid tumors. Programmatic cell death (PCD), such as apoptosis, ferroptosis, and autophagy, plays a crucial role in tumor development and chemotherapy sensitivity. Accumulating evidence suggests that some anti-tumor compounds and genes can induce massive production of reactive oxygen species (ROS) via inhibiting Nrf2 expression, which exacerbates oxidative stress and promotes Gastric cancer (GC) cell death, thereby enhancing the sensitivity of GC cells to chemotherapy-induced PCD. In this review, we summarize the role of antitumor drugs in interfering in three different types of PCD (apoptosis, ferroptosis, and autophagy) in GC cells by modulating Nrf2 expression, as well as the molecular mechanisms through which targeting Nrf2 brings about PCD and chemosensitivity. It is reasonable to believe that Nrf2 serves as a potential therapeutic target, and targeting Nrf2 by drug or gene regulation could provide a new strategy for the treatment of GC.

Adenosine A2A Receptor Antagonist Sch58261 Improves the Cognitive Function in Alzheimer's Disease Model Mice Through Activation of Nrf2 via an Autophagy-Dependent Pathway

Aims: Adenosine, an important endogenous neuromodulator, contributes to a broad set of several neurodegenerative diseases. The adenosine A2A receptor (A2AR) is the most involved in neuropathological effects and plays an important role in the pathogenesis of Alzheimer's disease (AD). However, the effect of A2AR antagonist and the underlying mechanism in AD model mice remains unclear. Results: The amyloid beta (Aβ)1-42-induced mice AD models were used in this study. Several behavioral experiments were performed to evaluate the improvement of AD mice treated with A2AR antagonist. For mechanism analysis, autophagy-related proteins, Kelch-like ECH-associated protein1 (Keap1)-nuclear factor erythroid-derived factor 2-related factor (Nrf2) pathway activation, and synaptic function were studied using Western blot, immunofluorescence, immunohistochemistry, transmission electron microscope, real-time quantitative PCR, and patch clamp. Pharmacological blockade of adenosine A2AR by SCH58261 (SCH) ameliorated cognitive deficits and decreased expression levels of several AD biomarkers, including Aβ and hyperphosphorylation of Tau. Moreover, SCH activated the Nrf2 pathway through autophagy mediated Keap1 degradation, resulting in the improvement of neuron autophagy dysfunction, synaptic plasticity, and synaptic transmission. Innovation: Our data clarified that the SCH (an antagonist of A2AR) could increase the level of autophagy, promote the ability of antioxidative stress by the activation of Keap1-Nrf2 pathway, and improve the synaptic function in Aβ1-42-induced AD mice or cell model, which provided a potential therapeutic strategy for AD. Conclusion: A2AR antagonism represents a promising strategy for the anti-AD agent development through autophagy-dependent pathway. Antioxid. Redox Signal. 41, 1117-1133.

Naturally-derived modulators of the Nrf2 pathway and their roles in the intervention of diseases

Cumulative evidence has verified that persistent oxidative stress is involved in the development of various chronic diseases, including pulmonary, neurodegenerative, kidney, cardiovascular, and liver diseases, as well as cancers. Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a pivotal role in regulating cellular oxidative stress and inflammatory reactions, making it a focal point for disease prevention and treatment strategies. Natural products are essential resources for discovering leading molecules for new drug research and development. In this review, we comprehensively outlined the progression of the knowledge on the Nrf2 pathway, Nrf2 activators in clinical trials, the naturally-derived Nrf2 modulators (particularly from 2014-present), as well as their effects on the pathogenesis of chronic diseases.

Repositioning Canagliflozin for Mitigation of Aluminium Chloride-Induced Alzheimer's Disease: Involvement of TXNIP/NLRP3 Inflammasome Axis, Mitochondrial Dysfunction, and SIRT1/HMGB1 Signalling

Background and Objectives: Alzheimer's disease (AD) is the most common neurodegenerative disorder in the world. Due to failure of the traditional drugs to produce a complete cure for AD, the search for new safe and effective lines of therapy has attracted the attention of ongoing research. Canagliflozin is an anti-diabetic agent with proven efficacy in the treatment of neurological disorders in which mitochondrial dysfunction, oxidative stress, apoptosis, and autophagy play a pathophysiological role. Elucidation of the potential effects of different doses of canagliflozin on AD induced by aluminium chloride in rats and exploration of the molecular mechanisms that may contribute to these effects were the primary objectives of the current study. Materials and Methods: In a rat model of AD, the effect of three different doses of canagliflozin on the behavioural, biochemical, and histopathological alterations induced by aluminium chloride was assessed. Results: Canagliflozin administered to aluminium chloride-treated animals induced dose-dependent normalisation in the behavioural tests, augmentation of the antioxidant defence mechanisms, inhibition of TXNIP/NLRP3 inflammasome signalling, modulation of the SIRT1/HMGB1 axis, interference with the pro-inflammatory and the pro-apoptotic mechanisms, and restoration of the mitochondrial functions and autophagy in the hippocampal tissues to approximately baseline values. In addition, canagliflozin exhibited an interesting dose-dependent ability to repress aluminium chloride-induced histopathological changes in the brain. Conclusions: The effects of canagliflozin on oxidative stress, mitochondrial functions, inflammatory pathways, and autophagy signals may open new gates towards the mitigation of the pathologic features of AD.

Metformin decelerates aging clock in male monkeys

In a rigorous 40-month study, we evaluated the geroprotective effects of metformin on adult male cynomolgus monkeys, addressing a gap in primate aging research. The study encompassed a comprehensive suite of physiological, imaging, histological, and molecular evaluations, substantiating metformin's influence on delaying age-related phenotypes at the organismal level. Specifically, we leveraged pan-tissue transcriptomics, DNA methylomics, plasma proteomics, and metabolomics to develop innovative monkey aging clocks and applied these to gauge metformin's effects on aging. The results highlighted a significant slowing of aging indicators, notably a roughly 6-year regression in brain aging. Metformin exerts a substantial neuroprotective effect, preserving brain structure and enhancing cognitive ability. The geroprotective effects on primate neurons were partially mediated by the activation of Nrf2, a transcription factor with anti-oxidative capabilities. Our research pioneers the systemic reduction of multi-dimensional biological age in primates through metformin, paving the way for advancing pharmaceutical strategies against human aging.