Osteoclast-Driven Polydopamine-to-Dopamine Release: An Upgrade Patch for Polydopamine-Functionalized Tissue Engineering Scaffolds.

Polydopamine, a mussel-inspired self-adherent polymer of dopamine, has impressive adhesive properties and thus is one of the most versatile approaches to functionalize tissue engineering scaffolds. To date, many types of polydopamine-functionalized scaffolds have been manufactured and extensively applied in bone tissue engineering at the preclinical stage. However, how polydopamine is biodegraded and metabolized during the bone healing process and the side effects of its metabolite remain largely unknown. These issues are often neglected in the modern manufacture of polydopamine-functionalized materials and restrict them from stepping forward to clinical applications. In this study, using our bioinspired polydopamine-laced hydroxyapatite collagen calcium silicate material as a representative of polydopamine-functionalized tissue engineering scaffolds, we discovered that polydopamine can be metabolized to dopamine specifically by osteoclasts, which we termed "osteoclast-driven polydopamine-to-dopamine release". The released dopamine showed an osteoinductive effect in vitro and promoted bone regeneration in calvarial critical-sized defects. The concept of "osteoclast-driven polydopamine-to-dopamine release" has considerable application potential. It could be easily adopted by other existing polydopamine-functionalized scaffolds: just by recruiting osteoclasts. Once adopted, scaffolds will obtain a dopamine-releasing function, which enables their modulation of osteoblast activity and hence elevates the osteoinductive effect. Thus, "osteoclast-driven polydopamine-to-dopamine release" serves as an upgrade patch, which is useful for many existing polydopamine-functionalized materials.

Advancements in Myopic Macular Foveoschisis Research.

BACKGROUND: Presently, the global prevalence of myopia and high myopia reaches approximately 1.95 billion and 277 million individuals, respectively. Projections suggest that by 2050, the number of people with myopia may rise to 4.758 billion and those with high myopia to 938 million. In highly myopic eyes, the occurrence of MF is reported to be as high as 8-33%. SUMMARY: This review comprehensively addresses the classification, pathogenesis, natural progression, concomitant pathologies, and therapeutic strategies for macular foveoschisis in highly myopic patients. KEY MESSAGES: In recent years, macular foveoschisis has emerged as a prevalent complication in individuals with high myopia, primarily resulting from the combination of inward traction by vitreoretinal adhesions and outward traction exerted by posterior scleral staphyloma on the retina. While some maintain partial visual stability over an extended period, others may progress to macular holes or even retinal detachment. For highly myopic patients with macular foveoschisis, the mainstay procedures are vitrectomy, macular buckle, and posterior scleral reinforcement. However, there is controversy about whether to perform inner limiting membrane peeling and gas filling.

Multifunctional TiN-MXene-Co@CNTs Networks as Sulfur/Lithium Host for High-Areal-Capacity Lithium-Sulfur Batteries.

The inevitable shuttling and slow redox kinetics of lithium polysulfides (LiPSs) as well as the uncontrolled growth of Li dendrites have strongly limited the practical applications of lithium-sulfur batteries (LSBs). To address these issues, we have innovatively constructed the carbon nanotubes (CNTs) encapsulated Co nanoparticles in situ grown on TiN-MXene nanosheets, denoted as TiN-MXene-Co@CNTs, which could serve simultaneously as both sulfur/Li host to kill "three birds with one stone" to (1) efficiently capture soluble LiPSs and expedite their redox conversion, (2) accelerate nucleation/decomposition of solid Li2S, and (3) induce homogeneous Li deposition. Benefiting from the synergistic effects, the TiN-MXene-Co@CNTs/S cathode with a sulfur loading of 2.5 mg cm-2 could show a high reversible specific capacity of 1129.1 mAh g-1 after 100 cycles at 0.1 C, and ultralong cycle life over 1000 cycles at 1.0 C. More importantly, it even achieves a high areal capacity of 6.3 mAh cm-2 after 50 cycles under a sulfur loading as high as 8.9 mg cm-2 and a low E/S ratio of 5.0 µL mg-1. Besides, TiN-MXene-Co@CNTs as Li host could deliver a stable Li plating/striping behavior over 1000 h.

Ropinirole suppresses LPS-induced periodontal inflammation by inhibiting the NAT10 in an ac4C-dependent manner.

BACKGROUND: Periodontitis is a chronic osteolytic inflammatory disease, where anti-inflammatory intervention is critical for restricting periodontal damage and regenerating alveolar bone. Ropinirole, a dopamine D2 receptor agonist, has previously shown therapeutic potential for periodontitis but the underlying mechanism is still unclear. METHODS: Human gingival fibroblasts (HGFs) treated with LPS were considered to mimic periodontitis in vitro. The dosage of Ropinirole was selected through the cell viability of HGFs evaluation. The protective effects of Ropinirole on HGFs were evaluated by detecting cell viability, cell apoptosis, and pro-inflammatory factor levels. The molecular docking between NAT10 and Ropinirole was performed. The interaction relationship between NAT10 and KLF6 was verified by ac4C Acetylated RNA Immunoprecipitation followed by qPCR (acRIP-qPCR) and dual-luciferase reporter assay. RESULTS: Ropinirole alleviates LPS-induced damage of HGFs by promoting cell viability, inhibiting cell apoptosis and the levels of IL-1ß, IL-18, and TNF-α. Overexpression of NAT10 weakens the effects of Ropinirole on protecting HGFs. Meanwhile, NAT10-mediated ac4C RNA acetylation promotes KLF6 mRNA stability. Upregulation of KLF6 reversed the effects of NAT10 inhibition on HGFs. CONCLUSIONS: Taken together, Ropinirole protected HGFs through inhibiting the NAT10 ac4C RNA acetylation to decrease the KLF6 mRNA stability from LPS injury. The discovery of this pharmacological and molecular mechanism of Ropinirole further strengthens its therapeutic potential for periodontitis.

Infrared Imageries of Human Body Activated by Tea Match the Hypothesis of Meridian System.

Human meridian (Jingluo) system was hypothesized by traditional Chinese medicine (TCM) for thousands of years, suggesting 12 normal meridian channels going through respective organs, carrying fluid and energy, and laying thermal effects. Some treatments based on meridians have been proved effective. However, existence of meridians has never been confirmed, let alone the lack of measurement for meridian phenotypes. Thermal effect is one of the major phenotypes of meridian metabolism. Infrared photograph was employed to display the picture of meridians since 1970. Unfortunately, no satisfactory results have been obtained. It is possible that only when a certain meridian is activated will there be thermal effect for successful infrared photograph. In this study, 13 types of tea were selected out of the herbs to activate the hypothesized 12 meridians for imagery taking. Forty-two volunteers took part in the experiment lasted for 13 days. Different tea was tested in different day. Infrared imageries of the human bodies were taken immediately after each tea was drunk. The highest temperatures of the fingers, palms, and above the organs were derived from the imageries and analyzed. The temperatures of the organs and fingers possibly connected by 12 hypothesized meridians rose together significantly following the meridian hypothesis. Infrared imageries showed quite clear shapes of the organs activated by different kinds of tea, e.g., heart and kidneys by yellow tea, etc. Some high temperature lines also matched the hypothetic meridians. Our work displayed the probable imageries of all the 12 hypothetic meridians for the first time, and proved with data that different foods may activate different organs following the meridian hypothesis, shedding light on a possible new method of targeted drug designs. Measurements of meridian phenotypes can be developed based on this method of activation. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-022-00090-x.

A case of early-onset periodontitis with vitamin D deficiency: A case report and literature review.

RATIONALE: Periodontitis is an inflammatory disease with multifactorial etiology. Vitamin D, a fat-soluble vitamin, has protective effects on inflammatory response in various systemic conditions. The clinical features of vitamin D deficiency include growth failure, hypotonia, pathologic fractures, rachitic rosary, tetany and so on. Here we present a case of 12-year-old girl affected by early-onset periodontitis accompanied with vitamin D deficiency. PATIENT CONCERNS: A 12-year-old girl with gingival redness, bleeding associated with tooth brushing, and mandibular anterior teeth movement, with difficulty in mastication for the past 2 months. There is no relevant family history or special systemic disease history. The serological microelement test showed vitamin D levels were significantly lower than normal range. Immunological test showed abnormal CD4+/CD8+(CD3+CD4+/CD3+CD8+) ratio as well. DIAGNOSES: Based on the clinical and serological findings, this patient was ultimately diagnosed with early-onset periodontitis accompanied with vitamin D deficiency. INTERVENTIONS: The main treatments for this patient were 3-fold: periodontal therapy, vitamin D supplement and oral hygiene instructions. OUTCOMES: Following 1-year therapy, periodontal conditions recovered and became stable. And serological vitamin D levels returned to normal range. LESSONS: The case of interest serves as an important reminder to clinicians, that the early-onset periodontitis may be associated with micronutrients abnormalities, and early-diagnosis and treatment could avoid the body heathy disorders.

Ferroptosis-related genes LPCAT3 and PGD are potential diagnostic biomarkers for osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is the most common chronic joint disease and how ferroptosis contributes to OA has garnered much attention recently. Bioinformatics promoted the discovery of ferroptosis-related biomarkers for OA. But since OA is a whole-joint disease, sensitive biomarkers for OA are still limited. We herein focused on subchondral bone, a joint component often-ignored by existing bioinformatic reports, to identify ferroptosis-related diagnostic biomarkers for OA. METHOD: Microarray datasets GSE51588 and GSE55457 were downloaded from Gene Expression Omnibus database. Ferroptosis-related differential expression genes (Ferr-DEGs) between OA and normal samples were identified and their functional enrichment was analyzed. Common genes for OA diagnosis were selected from Ferr-DEGs using the combination of SVM-RFE, LASSO regression, and RandomForest machine learning algorithms. Common genes' diagnostic value was verified by receiver operating characteristic (ROC) curve and their association with immune infiltration was analyzed by CIBERSORT. Finally, candidate gene's expression was verified in chondrocytes from OA patients and in an in vitro IL-1ß-induced OA model, by RT-PCR. RESULTS: Two ferroptosis-related genes, LPCAT3 and PGD, were identified as OA diagnostic biomarkers and confirmed by ROC diagnostic test. The association of LPCAT3 and PGD with the infiltration of several types of immune cells was identified. The decreased expression of LPCAT3 and PGD was both confirmed in OA chondrocytes and IL-1ß-induced OA condition. CONCLUSIONS: We identified ferroptosis-related genes LPCAT3 and PGD as potential diagnostic biomarkers for OA, which may offer insight into the role of ferroptosis in OA and provides useful information for the diagnosis and treatment of OA.

IL-17: Balancing Protective Immunity and Pathogenesis.

The biological role of interleukin 17 (IL-17) has been explored during recent decades and identified as a pivotal player in coordinating innate and adaptive immune responses. Notably, IL-17 functions as a double-edged sword with both destructive and protective immunological roles. While substantial progress has implicated unrestrained IL-17 in a variety of infectious diseases or autoimmune conditions, IL-17 plays an important role in protecting the host against pathogens and maintaining physiological homeostasis. In this review, we describe canonical IL-17 signaling mechanisms promoting neutrophils recruitment, antimicrobial peptide production, and maintaining the epithelium barrier integrity, as well as some noncanonical mechanisms involving IL-17 that elicit protective immunity.

Nrf2 differentially regulates osteoclast and osteoblast differentiation for bone homeostasis.

Nuclear factor erythroid-derived factor 2-related factor 2 (Nrf2) is a master regulator of antioxidant response and protects cells from excessive oxidative stress. Nrf2 emerges as a prospective therapeutic target for metabolic bone disorders, in which the balance between osteoblastic bone formation and osteoclastic bone resorption is disrupted. However, the molecular mechanism through which Nrf2 modulates bone homeostasis remains unclear. In this study, we compared the differences in Nrf2-mediated antioxidant response and ROS regulation in osteoblasts and osteoclasts, both in vitro and in vivo. Findings indicated a close connection between the Nrf2 expression and its related antioxidant response with osteoclasts than osteoblasts. We next pharmacologically manipulated the Nrf2-mediated antioxidant response during osteoclast or osteoblast differentiation. Nrf2 inhibition enhanced osteoclastogenesis, while its activation suppressed it. In contrast, osteogenesis decreased irrespective of whether Nrf2 was inhibited or activated. These findings highlight the distinct ways in which the Nrf2-mediated antioxidant response regulates osteoclast and osteoblast differentiation, thereby contributing to the development of Nrf2 targeted therapies for metabolic bone diseases.

Recent developments and perspectives of MXene-Based heterostructures in photocatalysis.

Energy crises and environmental degradation are serious in recent years. Inexhaustible solar energy can be used for photocatalytic hydrogen production or CO2 reduction to reduce CO2 emissions. At present, the development of efficient photocatalysts is imminent. MXene as new two-dimensional (2D) layered material, has been used in various fields in recent years. Based on its high conductivity, adjustable band gap structure and sizable specific surface area, the MXene is beneficial to hasten the separation and reduce the combination of photoelectron-hole pairs in photocatalysis. Nevertheless, the re-stacking of layers because of the strong van der Waals force and hydrogen bonding interactions seriously hinder the development of MXene material as photocatalysts. By contrast, the MXene-based heterostructures composed of MXene nanosheets and other materials not only effectively suppress the re-stacking of layers, but also show the superior synergistic effects in photocatalysis. Herein, the recent progress of the MXene-based heterostructures as photocatalysts in energy and environment fields is summarized in this review. Particularly, new synthetic strategies, morphologies, structures, and mechanisms of MXene-based heterostructures are highlighted in hydrogen production, CO2 reduction, and pollutant degradation. In addition, the structure-activity relationship between the synthesis strategy, components, morphology and structure of MXene-based heterostructures, and their photocatalytic properties are elaborated in detail. Finally, a summary and the perspectives on improving the application study of the heterostructures in photocatalysis are presented.

Dual-Conductive CoSe2 @TiSe2 -C Heterostructures Promoting Overall Sulfur Redox Kinetics under High Sulfur Loading and Lean Electrolyte.

Although lithium-sulfur batteries (LSBs) possess a high theoretical specific capacity and energy density, the inherent problems including sluggish sulfur conversion kinetics and the shuttling of soluble lithium polysulfides (LiPSs) have severely hindered the development of LSBs. Herein, cobalt selenide (CoSe2 ) polyhedrons anchored on few-layer TiSe2 -C nanosheets derived from Ti3 C2 Tx MXenes (CoSe2 @TiSe2 -C) are reported for the first time. The dual-conductive CoSe2 @TiSe2 -C heterostructures can accelerate the conversion reaction from liquid LiPSs to solid Li2 S and promote Li2 S dissociation process through high conductivity and lowered reaction energy barriers for promoting overall sulfur redox kinetics, especially under high sulfur loadings and lean electrolyte. Electrochemical analysis and density functional theory calculation results clearly reveal the catalytic mechanisms of the CoSe2 @TiSe2 -C heterostructures from the electronic structure and atomic level. As a result, the cell with CoSe2 @TiSe2 -C interlayer maintains a superior cycling performance with 842.4 mAh g-1  and a low-capacity decay of 0.031% per cycle over 800 cycles at 1.0 C under a sulfur loading of 2.5 mg cm-2 . More encouragingly, it with a high sulfur loading of ≈7.0 mg cm-2  still harvests a high areal capacity of ≈6.25 mAh cm-2  under lean electrolyte (electrolyte/sulfur, E/S ≈ 4.5 µL mg-1 ) after 50 cycles at 0.05 C.

Optineurin regulates NRF2-mediated antioxidant response in a mouse model of Paget's disease of bone.

Degenerative diseases affecting the nervous and skeletal systems affect the health of millions of elderly people. Optineurin (OPTN) has been associated with numerous neurodegenerative diseases and Paget's disease of bone (PDB), a degenerative bone disease initiated by hyperactive osteoclastogenesis. In this study, we found age-related increase in OPTN and nuclear factor E2-related factor 2 (NRF2) in vivo. At the molecular level, OPTN could directly interact with both NRF2 and its negative regulator Kelch-like ECH-associated protein 1 (KEAP1) for up-regulating antioxidant response. At the cellular level, deletion of OPTN resulted in increased intracellular reactive oxygen species and increased osteoclastogenic potential. At the tissue level, deletion of OPTN resulted in substantially increased oxidative stress derived from leukocytes that further stimulate osteoclastogenesis. Last, curcumin attenuated hyperactive osteoclastogenesis induced by OPTN deficiency in aged mice. Collectively, our findings reveal an OPTN-NRF2 axis maintaining bone homeostasis and suggest that antioxidants have therapeutic potential for PDB.

Potential role of tea drinking in preventing hyperuricaemia in rats: biochemical and molecular evidence.

BACKGROUND: Lifestyle and diet play a significant role in hyperuricaemia. Accumulating evidence indicates that tea consumption is associated with hyperuricaemia and gout. However, diverse compounds in different types of tea make it quite difficult to determine the relevant molecular mechanism. Here, we compared the effects of six types of tea on hyperuricaemia induced by potassium oxonate (PO) and hypoxanthine in rats and investigated the possible underlying mechanisms. METHODS: Rats were randomly assigned to ten groups: the control, hyperuricaemia model, benzbromarone positive control, traditional Chinese medicine Simiao San positive control, green tea, yellow tea, black tea, white tea, red tea, and cyan tea treatment groups. After 21 days, uric acid (UA), xanthine oxidase (XOD), alanine aminotransferase (ALT),blood urea nitrogen (BUN), and creatinine (CRE) were assessed. Serum levels of interleukin-1ß (IL-1ß) were measured with an enzyme-linked immunosorbent assay. Haematoxylin-eosin staining and immunohistochemistry were used to assess liver and kidney injury. RESULTS: The levels of UA, CRE, and BUN in the treatment group were decreased to varying degrees. There was a significant reduction in UA, CRE, and BUN levels for yellow tea compared to the positive control drugs. Yellow tea suppressed XOD activity and alleviated hepatic and kidney injury. Network pharmacology and untargeted metabolomics indicated that ten yellow tea bioactive ingredients and 35 targets were responsible for preventing hyperuricaemia, which was mediated by 94 signalling pathways, including IL-1ß and TNF. CONCLUSION: These findings indicate that green tea cannot reduce the serum uric acid level of hyperuricaemic rats. Yellow tea can significantly improve hyperuricaemia by regulating the inflammatory response, autophagy, and apoptosis. This study provides a potential candidate for the treatment of hyperuricaemia and a basis for selecting therapeutic tea for patients with hyperuricaemia.

Retraction: MicroRNA-218 inhibits proliferation and invasion in ovarian cancer by targeting Runx2.

[This retracts the article DOI: 10.18632/oncotarget.21069.].

Evaluation of Optimal Sites for the Insertion of Orthodontic Mini Implants at Mandibular Symphysis Region through Cone-Beam Computed Tomography.

This study aims to evaluate the overall bone thickness (OBT) and cortical bone thickness (CBT) of mandibular symphysis and to determine the optimal sites for the insertion of orthodontic mini implants. Cone-beam computed tomography (CBCT) images of 32 patients were included in this study. The sample was further categorized into three facial types: low-, average-, and high-angle. OBT and CBT were measured at the mandibular symphysis region. All measurements were performed at six different heights from the cementoenamel junction [CEJ] and at seven different angles to the occlusal plane. Analysis of variance (ANOVA) was used for statistical comparison and a p value less than 0.05 was considered statistically significant. Our results revealed that neither OBT nor CBT was influenced by age or sex, except for the observation that CBT was significantly greater in adults than in adolescents. OBT and CBT were significantly greater in low-angle cases than in average- and high-angle cases. Both OBT and CBT were significantly influenced by insertion locations, heights and angles, and their interactions. CBT and OBT were greatest at the location between two lower central incisors, and became greater with increases in insertion height and angle. Both recommended and optimal insertion sites were mapped. The mandibular symphysis region was suitable for the placement of orthodontic mini implants. The optimal insertion site was 6-10 mm apical to the CEJ between two lower central incisors, with an insertion angle being 0-60 degrees to the occlusal plane.

Surgical management and outcomes of pediatric open globe injuries requiring vitrectomy.

PURPOSE: To describe surgical management and establish visual outcomes of open globe injury (OGI) in pediatric patients requiring vitrectomy. METHODS: Forty-eight eyes of 48 pediatric patients underwent vitrectomy for OGI with secondary vitreoretinal complications in the eye center of Jilin University were included. Characteristics of patients, details of ocular examination and operation, presenting and final visual acuity were recorded. RESULTS: Presenting visual acuity less than 20/400 was found in 44 eyes (91.7%), which included no light perception (NLP) in four eyes. At last visit, there was no eyes with visual acuity of NLP, and 19 eyes (39.6%) had a vision recovery to 20/400 or better. Mechanisms of injury, intraocular contents prolapse, presence of hyphema, intraocular foreign body, vitreous hemorrhage, retinal detachment, and total time from injury to PPV > 2 weeks were significant predictors of visual prognosis. Logistic regression analysis showed that hyphema was a significant predictive factor for poor visual outcome. CONCLUSION: Visual acuity was improved in most of the patients with OGI in this study. Hyphema is an important presenting ocular sign in estimating the post-vitrectomy visual outcome for OGI in children. Proper timing of vitrectomy is suggested, and in this study patients may benefit more with early vitrectomy as less proliferative vitreoretinopathy (PVR) was found together with a better visual acuity.

Biomimetic polydopamine-laced hydroxyapatite collagen material orients osteoclast behavior to an anti-resorptive pattern without compromising osteoclasts' coupling to osteoblasts.

Polydopamine-assisted modification for bone substitute materials has recently shown great application potential in bone tissue engineering due to its excellent biocompatibility and adhesive properties. A scaffold material's impact on osteoclasts is equally as important as its impact on osteoblasts when considering tissue engineering for bone defect repair, as healthy bone regeneration requires an orchestrated coupling between osteoclasts and osteoblasts. How polydopamine-functionalized bone substitute materials modulate the activity of osteoblast lineage cells has been extensively investigated, but much less is known about their impact on osteoclasts. Moreover, most of the polydopamine-functionalized materials would need to additionally load a biomolecule to exert the modulation on osteoclast activity. Herein, we demonstrated that our biomimetic polydopamine-laced hydroxyapatite collagen (PDHC) scaffold material, which does not need to load additional bioactive agent, is sufficiently able to modulate osteoclast activity in vitro. First, PDHC showed an anti-resorptive potential, characterized by decreased osteoclast differentiation and resorption capacity and changes in osteoclasts' transcriptome profile. Next, cAMP response element-binding protein (CREB) activity was found to mediate PDHC's anti-osteoclastogenic effect. Finally, although PDHC altered clastokines expression pattern of osteoclasts, as revealed by transcriptomic and secretomic analysis, osteoclasts' coupling to osteoblasts was not compromised by PDHC. Collectively, this study demonstrated the PDHC material orients osteoclast behavior to an anti-resorptive pattern without compromising osteoclasts' coupling to osteoblasts. Such a feature is favorable for the net increase of bone mass, which endows the PDHC material with great application potential in preclinical/clinical bone defect repair.

Erratum: MiR-143 targets CTGF and exerts tumor-suppressing functions in epithelial ovarian cancer.

[This corrects the article on p. 2716 in vol. 8, PMID: 27398154.].

Deficiency of optineurin enhances osteoclast differentiation by attenuating the NRF2-mediated antioxidant response.

Abnormally increased resorption contributes to bone degenerative diseases such as Paget's disease of bone (PDB) through unclear mechanisms. Recently, the optineurin (OPTN) gene has been implicated in PDB, and global OPTN knockout mice (Optn-/-) were shown to exhibit increased formation of osteoclasts (osteoclastogenesis). Growing evidence, including our own, has demonstrated that intracellular reactive oxygen species (ROS) stimulated by receptor activator of nuclear factor kappa-B ligand (RANKL) can act as signaling molecules to promote osteoclastogenesis. Here, we report that OPTN interacts with nuclear factor erythroid-derived factor 2-related factor 2 (NRF2), the master regulator of the antioxidant response, defining a pathway through which RANKL-induced ROS could be regulated for osteoclastogenesis. In this study, monocytes from Optn-/- and wild-type (Optn+/+) mice were utilized to differentiate into osteoclasts, and both qRT-PCR and tartrate-resistant acid phosphatase (TRAP) staining showed that the Optn-/- monocytes exhibited enhanced osteoclastogenesis compared to the Optn+/+ cells. CellROX® staining, qRT-PCR, and Western blotting indicated that OPTN deficiency reduced the basal expression of Nrf2, inhibited the expression of NRF2-responsive antioxidants, and increased basal and RANKL-induced intracellular ROS levels, leading to enhanced osteoclastogenesis. Coimmunoprecipitation (co-IP) showed direct interaction, and immunofluorescence staining showed perinuclear colocalization of the OPTN-NRF2 granular structures during differentiation. Finally, curcumin and the other NRF2 activators attenuated the hyperactive osteoclastogenesis induced by OPTN deficiency. Collectively, our findings reveal a novel OPTN-mediated mechanism for regulating the NRF2-mediated antioxidant response in osteoclasts and extend the therapeutic potential of OPTN in the aging process resulting from ROS-triggered oxidative stress, which is associated with PDB and many other degenerative diseases.