Immobilization of antimony in soil and groundwater using ferro-magnesium bimetallic organic frameworks.

Sb(III) is often detected in contaminated soil and groundwater. Hence, high-efficiency technology is needed. In this study, bimetallic organic frameworks were used for the first time to immobilize Sb(III) from contaminated soil and groundwater. The materials were synthesized by the hydrothermal method. Both ends of the prepared material were hexagonal tip rods, and the length became shorter as the ratio of Fe/Mg decreased. The bimetallic organic framework with a Fe/Mg feeding ratio of 0.5 was the optimum material for Sb(III) removal, which could effectively immobilize Sb(III). The adsorption isotherm was fitted well with the Freundlich model, and the optimal adsorption capacity can reach 106.97 mg/g. The adsorption capacity of 84% can be completed in 10 min, which conformed to the pseudo-second-order kinetics. The Fe3+ could enhance the stability of the material, and the Mg2+ was conducive to freeing up adsorption sites for binding Sb(III) and forming stable chemical adsorption. Ion exchange is the predominant mechanism to remove Sb(III). After 14 days of remediation of Sb(III) contaminated soil, the Toxicity Characteristic Leaching Procedure (TCLP)-leached concentrations of Sb(III) were reduced by 86%, 91% and 94% when the material dosages were 1%, 2% and 3%, respectively. Immobilization of Sb(III) in soil resulted in a conversion of antimony speciation from more easily bioavailable species to less bioavailable species, further contributing to reduce the environmental risk of antimony. The results indicate that ferro-magnesium bimetallic organic frameworks may serve as a kind of promising materials for the immobilization of Sb(III) in contaminated soil and groundwater.

Dual-dynamic-bond cross-linked injectable hydrogel of multifunction for intervertebral disc degeneration therapy.

Developing smart hydrogels with integrated and suitable properties to treat intervertebral disc degeneration (IVDD) by minimally invasive injection is of high desire in clinical application and still an ongoing challenge. In this work, an extraordinary injectable hydrogel PBNPs@OBG (Prussian blue nanoparticles@oxidized hyaluronic acid/borax/gelatin) with promising antibacterial, antioxidation, rapid gelation, and self-healing characteristics was designed via dual-dynamic-bond cross-linking among the oxidized hyaluronic acid (OHA), borax, and gelatin. The mechanical performance of the hydrogel was studied by dynamic mechanical analysis. Meanwhile, the swelling ratio and degradation level of the hydrogel was explored. Benefiting from its remarkable mechanical properties, sufficient tissue adhesiveness, and ideal shape-adaptability, the injectable PBNPs containing hydrogel was explored for IVDD therapy. Astoundingly, the as-fabricated hydrogel was able to alleviate H2O2-induced excessive ROS against oxidative stress trauma of nucleus pulposus, which was further revealed by theoretical calculations. Rat IVDD model was next established to estimate therapeutic effect of this PBNPs@OBG hydrogel for IVDD treatment in vivo. On the whole, combination of the smart multifunctional hydrogel and nanotechnology-mediated antioxidant therapy can serve as a fire-new general type of therapeutic strategy for IVDD and other oxidative stress-related diseases.

PLK1 Mitigates Intervertebral Disc Degeneration by Delaying Senescence of Nucleus Pulposus Cells.

Intervertebral disc degeneration (IVDD) is the primary cause of low back pain; however, the molecular mechanisms involved in the pathogenesis of IVDD are not fully understood. Polo-like kinase 1 (PLK1) plays numerous roles in the cell cycle, including in cell proliferation and senescence. To investigate the involvement of PLK1 in IVDD, we used patient tissues and an animal model of IVDD. Samples were analyzed via immunoblotting, quantitative real-time polymerase chain reaction (qPCR), immunofluorescence, and immunohistochemistry. Our results demonstrated that PLK1 expression was decreased in nucleus pulposus cells (NPCs) of degenerative IVDs. The inhibition of PLK1 kinase activity in normal NPCs increased the expression of p53 protein, inhibited cell proliferation, and induced senescence. Our results suggest that PLK1 regulates the degeneration of the IVD through p53, revealing the function and mechanism of PLK1 in IVDD and providing a theoretical basis and experimental evidence for the potential treatment of low back pain.

Oxidative stress-induced circKIF18A downregulation impairs MCM7-mediated anti-senescence in intervertebral disc degeneration.

Low back pain, triggered by intervertebral disc degeneration (IVDD), is one of the most common causes of disability and financial expenditure worldwide. However, except for surgical interventions, effective medical treatment to prevent the progression of IVDD is lacking. This study aimed to investigate the effects of circKIF18A, a novel circRNA, on IVDD progression and to explore its underlying mechanism in IVDD. In this study, we found that oxidative stress was positively correlated with nucleus pulposus cell (NPC) senescence in IVDD and that circKIF18A was downregulated in IVDD and attenuated senescent phenotypes such as cell cycle arrest and extracellular matrix degradation in NPCs. Mechanistically, circKIF18A competitively suppressed ubiquitin-mediated proteasomal degradation of MCM7, and the protective effects of circKIF18A on NPCs were partially mediated by MCM7 under oxidative stress. Intradiscal injection of adenoviral circKIF18A ameliorated IVDD in a rat model. This study revealed that circKIF18A regulates NPC degeneration by stabilizing MCM7 and identified a novel signaling pathway, the circKIF18A-MCM7 axis, for anti-senescence molecular therapy in IVDD.

CircRNA circTIAM1 promotes papillary thyroid cancer progression through the miR-646/HNRNPA1 signaling pathway.

Papillary thyroid cancer (PTC) is a common endocrine tumor with a rapidly increasing incidence in recent years. Although the majority of PTCs are relatively indolent and have a good prognosis, a certain proportion is highly aggressive with lymphatic metastasis, iodine resistance, and easy recurrence. Circular RNAs (circRNAs) are a class of noncoding RNAs that are linked to a variety of tumor processes in several cancers, including PTC. In the current study, circRNA high-throughput sequencing was performed to identify alterations in circRNA expression levels in PTC tissues. circTIAM1 was then selected because of its increased expression in PTC and association with apoptosis, proliferation, and migration of PTC cells in vitro and in vivo. Mechanistically, circTIAM1 acted as a sponge of microRNA-646 and functioned in PTC by targeting miR-646 and heterogeneous ribonucleoprotein A1. Fluorescence in situ hybridization and dual-luciferase reporter assays further confirmed these connections. Overall, our results reveal an important oncogenic role of circTIAM1 in PTC and may represent a potentially therapeutic target against PTC progression.

circSPG21 protects against intervertebral disc disease by targeting miR-1197/ATP1B3.

The abnormal expression of circular RNAs (circRNAs) is associated with numerous human diseases. This study investigated the mechanism by which circRNA acts as competitive endogenous RNA in the regulation of degenerative intervertebral disc disease (IVDD). Decreased expression of circSPG21 was detected in degenerated nucleus pulposus cells (NPCs), the function of circSPG21 in NPCs was explored and verified, and the downstream target of circSPG21 was investigated. The interaction between circSPG21 and miR-1197 and its target gene (ATP1B3) was studied by online database prediction and molecular biological verification. Finally, the circSPG21/miR-1197/ATP1B3 axis was verified in the mouse tail-looping model. The expression of circSPG21 in the nucleus pulposus in IVDD was directly related to an imbalance of anabolic and catabolic factors, which affected cell senescence. circSPG21 was found to play a role in human NPCs by acting as a sponge of miR-1197 and thereby affecting ATP1B3. The regulation of circSPG21 provides a potentially effective therapeutic strategy for IVDD.

Microwave-enhanced reductive immobilization of high concentrations of chromium in a field soil using iron polysulfide.

High concentrations of Cr(VI) are often detected in contaminated soil. Yet, cost-effective remediation technologies have been lacking. In this study, we prepared a type of FeSx based on commercial FeSO4.7H2O and CaSx and tested a microwave-assisted technology based on FeSx for reductive immobilization of high concentrations of Cr(VI) in a field contaminated soil. The as-prepared FeSx particles appeared as a honeycomb-like and highly porous structure. The microwave-assisted FeSx reduction process was able to rapidly reduce the TCLP-based reachability of Cr(VI) from 391.8 to 2.6 mg·L-1. The dosage of FeSx, S/Fe molar ratio, initial moisture content, microwave power, and irradiation time can all affect the treatment effectiveness. After 500 days curing under atmospheric conditions, the TCLP-leached concentration of Cr remained below the regulatory limit of 5 mg·L-1, while other treatments failed to meet the goal. Sx2- or S2- served as the primary electron donors, whereas Fe facilitated the microwave absorption and the formation of the stable final product of FeCr2O4. S and Fe are mostly precipitated in soil. The microwave-assisted FeSx reduction was shown to be an effective approach to rapidly reduce the leachability of Cr(VI) in contaminated soil, especially in heavily contaminated soil.

miR-21-5p targets SKP2 to reduce osteoclastogenesis in a mouse model of osteoporosis.

Osteoporosis results from an imbalance between bone formation and bone resorption. Traditional drugs for treating osteoporosis are associated with serious side effects, and thus, new treatment methods are required. This study investigated the role of differentially expressed microRNAs during osteoclast differentiation and osteoclast activity during osteoarthritis as well as the associated underlying mechanisms. We used a microarray to screen microRNAs that decreased in the process of osteoclast differentiation and verified miR-21-5p to decrease significantly using RT-qPCR. In follow-up experiments, we found that miR-21-5p targets SKP2 to regulate osteoclast differentiation. In vivo, ovariectomized mice were used to simulate perimenopausal osteoporosis induced by estrogen deficiency, and miR-21-5p treatment inhibited bone resorption and maintained bone cortex and trabecular structure. These results suggest that miR-21-5p is a new therapeutic target for osteoporosis.

Inhibition of intervertebral disc disease progression via the circPKNOX1-miR-370-3p-KIAA0355 axis.

The molecular mechanism underlying the development of intervertebral disc disease (IVDD) is not completely understood. Circular RNAs (circRNAs) play a significant role in the occurrence and development of various diseases, and studies have shown that circPKNOX1 is involved in the compensatory response of extracellular matrix synthesis and secretion of the nucleus pulposus (NP) cells. However, the mechanism through which circRNAs regulate IVDD progression remains unclear; therefore, in this study, we explored the significance of circPKNOX1 in IVDD. The expression of circRNAs in NP cells of normal and degenerative patients was detected using microarray analysis, and the role of circPKNOX1 in IVDD was confirmed using RT-qPCR. The interaction networks of circRNAs, miRNAs, and miRNA target genes were detected using bioinformatics analysis, RNA fluorescence in situ hybridization, and immunofluorescence analysis. We found that the expression of circPKNOX1 decreased in IVDD cells. The expression of circPKNOX1 in NP cells, observed using RT-qPCR and western blotting, was consistent with that observed using array screening. Overexpression of circPKNOX1 increased the expression of collagen II, aggrecan, and SOX9 and decreased that of ADAMTS4, ADAMTS-5, MMP3, and MMP13. We further demonstrated that circPKNOX1 played the role of a sponge by competitively binding miR-370-3p to reverse the inhibition of KIAA0355 expression. Our findings indicated that circPKNOX1 affected the progression of IVDD by regulating the expression of KIAA0355 via miR-370-3p. Therefore, circPKNOX1-based therapy may serve as an effective IVDD treatment strategy.

The Presence of Thyroid Cartilage at the Surgical Level Reduces Early Dysphagia after Single-Level Anterior Cervical Surgery: A Retrospective Study.

Background: Early dysphagia is a frequent complication of anterior cervical (AC) spine surgery. However, there are no reports that have discussed the correlation between early dysphagia and the positional relationship between thyroid cartilage and the surgical level.Methods: We retrospectively enrolled 82 patients in our hospital who underwent single-level AC discectomy performed by the same surgeon using the same internal fixation apparatus from 2015 to 2017. Swallowing difficulty was rated during the first five postoperative days using a 10-point scoring system. The positional relationship between the thyroid cartilage and the surgical level was defined as discectomy within the thyroid cartilage (IN group) or outside the thyroid cartilage (OUT group) using preoperative computed tomography (CT) images. The confounding factors such as gender, age, body mass index (BMI), hypertension, diabetes mellitus, drinking, smoking, operative level, operative time, and blood loss were analyzed by a binomial logistic regression.Results: The thyroid cartilage was most commonly located above the C5 level (65.1%). Early dysphagia developed in 47.6% of the patients during the first five postoperative days. The IN and OUT groups each contained 41 cases. The difference in the cumulative postoperative early dysphagia score between the IN and OUT groups was statistically significant (p < .05). The factors of gender, age, BMI, hypertension, diabetes mellitus, drinking, smoking, operative level, operative time, blood loss did not significantly influence the incidence of postoperative early dysphagia.Conclusions: We found that early dysphagia, which is a self-limiting complication, was correlated with surgery performed at levels outside the thyroid cartilage region. Preoperative review of the positional relationship between the thyroid cartilage and the surgical level can predict the incidence of postoperative transient dysphagia.

BRD4 inhibition regulates MAPK, NF-κB signals, and autophagy to suppress MMP-13 expression in diabetic intervertebral disc degeneration.

Diabetes mellitus may lead to intervertebral disc degeneration (IVDD). Matrix metalloproteinase-13 (MMP-13) is one of the major catabolic factors in extracellular matrix (ECM) metabolism of nucleus pulposus cells (NPCs) and contributes to diabetic IVDD. Bromodomain-containing protein 4 (BRD4) is a member of the bromodomain and extraterminal protein family and is implicated in chronic inflammation. Here, we report that the expression of BRD4 and MMP-13 was elevated in diabetic nucleus pulposus tissues as well as in advanced glycation end products (AGEs)-treated NPCs; also, the regulatory effect of BRD4 on MMP-13 was studied. We found that MMP-13 was regulated by MAPK and NF-κB signaling as well as autophagy in AGEs-treated NPCs. Next, we explored the role of BRD4 in regulation of MAPK, NF-κB signaling, and autophagy. The results showed that BRD4 is the upstream regulator of all of these 3 factors, and inhibition of BRD4 may suppress MAPK and NF-κB signaling while activating autophagy in AGEs-treated NPCs. Finally, we demonstrated that BRD4 inhibition may suppress MMP-13 expression in diabetic NPCs in vitro as well as in vivo; meanwhile, it may preserve ECM in diabetic rats. Our study demonstrates that inhibition of BRD4 may suppress MAPK and NF-κB signaling and activate autophagy to suppress MMP-13 expression in diabetic IVDD, and diabetic IVDD may be compromised by BRD4 inhibitors.-Wang, J., Hu, J., Chen, X., Huang, C., Lin, J., Shao, Z., Gu, M., Wu, Y., Tian, N., Gao, W., Zhou, Y., Wang, X., Zhang, X. BRD4 inhibition regulates MAPK, NF-κB signals, and autophagy to suppress MMP-13 expression in diabetic intervertebral disc degeneration.

Altered X-chromosome inactivation in T cells may promote sex-biased autoimmune diseases.

Systemic lupus erythematosus (SLE) is an autoimmune disorder that predominantly affects women and is driven by autoreactive T cell-mediated inflammation. It is known that individuals with multiple X-chromosomes are at increased risk for developing SLE; however, the mechanisms underlying this genetic basis are unclear. Here, we use single cell imaging to determine the epigenetic features of the inactive X (Xi) in developing thymocytes, mature T cell subsets, and T cells from SLE patients and mice. We show that Xist RNA and heterochromatin modifications transiently reappear at the Xi and are missing in mature single positive T cells. Activation of mature T cells restores Xist RNA and heterochromatin marks simultaneously back to the Xi. Notably, X-chromosome inactivation (XCI) maintenance is altered in T cells of SLE patients and late-stage-disease NZB/W F1 female mice, and we show that X-linked genes are abnormally upregulated in SLE patient T cells. SLE T cells also have altered expression of XIST RNA interactome genes, accounting for perturbations of Xi epigenetic features. Thus, abnormal XCI maintenance is a feature of SLE disease, and we propose that Xist RNA localization at the Xi could be an important factor for maintaining dosage compensation of X-linked genes in T cells.

BRD4 inhibition attenuates inflammatory response in microglia and facilitates recovery after spinal cord injury in rats.

The pathophysiology of spinal cord injury (SCI) involves primary injury and secondary injury. For the irreversibility of primary injury, therapies of SCI mainly focus on secondary injury, whereas inflammation is considered to be a major target for secondary injury; however the regulation of inflammation in SCI is unclear and targeted therapies are still lacking. In this study, we found that the expression of BRD4 was correlated with pro-inflammatory cytokines after SCI in rats; in vitro study in microglia showed that BRD4 inhibition either by lentivirus or JQ1 may both suppress the MAPK and NF-κB signalling pathways, which are the two major signalling pathways involved in inflammatory response in microglia. BRD4 inhibition by JQ1 not only blocked microglial M1 polarization, but also repressed the level of pro-inflammatory cytokines in microglia in vitro and in vivo. Furthermore, BRD4 inhibition by JQ1 can improve functional recovery and structural disorder as well as reduce neuron loss in SCI rats. Overall, this study illustrates that microglial BRD4 level is increased after SCI and BRD4 inhibition is able to suppress M1 polarization and pro-inflammatory cytokine production in microglia which ultimately promotes functional recovery after SCI.

Baicalein Inhibits the IL-1ß-Induced Inflammatory Response in Nucleus Pulposus Cells and Attenuates Disc Degeneration In vivo.

Intervertebral disc degeneration (IDD) is widely considered one of the main causes of low back pain, which is a chronic progressive disease closely related to inflammation and degeneration of nucleus pulposus (NP) cells. Baicalein is a natural bioactive compound with anti-inflammatory effects in different diseases, including inhibition of the inflammatory response in chondrocytes, whose morphology and avascular supply are similar to those of NP cells. Therefore, we hypothesized that baicalein may have a therapeutic effect on IDD by suppressing the inflammatory response. In vitro, NP cells were pretreated with baicalein for 2 h and then incubated with IL-1ß for 24 h. We found that baicalein not only inhibited the overexpression of inflammatory cytokine production, including NO, PGE2, TNF-α, and IL-6, but also suppressed the expression of COX-2 and iNOS. The IL-1ß-induced overexpression of MMP13 and ADAMTS5 and degradation of aggrecan and type II collagen were reversed by baicalein in a dose-dependent manner. Mechanistically, we found that baicalein suppressed the IL-1ß-induced activation of the NF-κB and MAPK pathways. Moreover, an in vivo study demonstrated that baicalein treatment could ameliorate IDD in a puncture-induced rat model. Thus, baicalein has great value as a potential therapeutic agent for IDD.

Genistein protects intervertebral discs from degeneration via Nrf2-mediated antioxidant defense system: An in vitro and in vivo study.

Oxidative stress has been reported to be closely associated with the development of intervertebral disc degeneration (IDD). IDD is one of the major causes of low back pain. Genistein (GES), one of the main isoflavones of soybean, has been shown to exert multiple biological functions on different diseases. Here, we tested the therapeutic potential of GES for IDD. In vitro experiments, we confirmed GES was nontoxic to rat nucleus pulposus cells (NPCs) within the concentration of 100 µM. Furthermore, GES was able to suppress apoptosis in tert-butyl hydroperoxide (TBHP)-treated NPCs. In the aspect of extracellular matrix (ECM), GES not only reduced metalloproteinase-13 (MMP-13) and a disintegrin-like and MMP thrombospondin type 1 motif 5 expression, but also increased aggrecan and type II collagen levels. Also, we found GES might rescue TBHP-induced NPCs degeneration by enhancing Nrf2-mediated antioxidant defense system. Silencing Nrf2 partly abolished the protective effects of GES on apoptosis and ECM disruption in TBHP-treated NPCs. Correspondingly, GES ameliorated IDD in a rat model by preserving morphology of degenerative intervertebral discs and promoting Nrf2 expression. To sum up, our study suggests that GES exerts protective effects in NPCs against degeneration and reveals the underlying mechanism of GES on Nrf2 activation in NPCs.

Melatonin ameliorates intervertebral disc degeneration via the potential mechanisms of mitophagy induction and apoptosis inhibition.

Intervertebral disc degeneration (IDD) is a complicated disease in patients. The pathogenesis of IDD encompasses cellular oxidative stress, mitochondrion dysfunction and apoptosis. Melatonin eliminates oxygen free radicals, regulates mitochondrial homoeostasis and function, stimulates mitophagy and protects against cellular apoptosis. Therefore, we hypothesize that melatonin has beneficial effect on IDD by mitophagy stimulation and inhibition of apoptosis. The effects of melatonin on IDD were investigated in vitro and in vivo. For the former, melatonin diminished cellular apoptosis caused by tert-butyl hydroperoxide in nucleus pulposus (NP) cells. Mitophagy, as well as its upstream regulator Parkin, was activated by melatonin in both a dose and time-dependent manner. Mitophagy inhibition by cyclosporine A (CsA) partially eliminated the protective effects of melatonin against NP cell apoptosis, suggesting that mitophagy is involved in the protective effect of melatonin on IDD. In addition, melatonin was demonstrated to preserve the extracellular matrix (ECM) content of Collagen II, Aggrecan and Sox-9, while inhibiting the expression of matrix degeneration enzymes, including MMP-13 and ADAMTS-5. In vivo, our results demonstrated that melatonin treatment ameliorated IDD in a puncture-induced rat model. To conclude, our results suggested that melatonin protected NP cells against apoptosis via mitophagy induction and ameliorated disc degeneration, providing the potential therapy for IDD.

Melatonin protects endothelial progenitor cells against AGE-induced apoptosis via autophagy flux stimulation and promotes wound healing in diabetic mice.

Wound healing is delayed in diabetic patients. Increased apoptosis and endothelial progenitor cell (EPC) dysfunction are implicated in delayed diabetic wound healing. Melatonin, a major secretory product of the pineal gland, promotes diabetic wound healing; however, its mechanism of action remains unclear. Here, EPCs were isolated from the bone marrow of mice. Treatment of EPCs with melatonin alleviated advanced glycation end product (AGE)-induced apoptosis and cellular dysfunction. We further examined autophagy flux after melatonin treatment and found increased light chain 3 (LC3) and p62 protein levels in AGE-treated EPCs. However, lysosome-associated membrane protein 2 expression was decreased, indicating that autophagy flux was impaired in EPCs treated with AGEs. We then evaluated autophagy flux after melatonin treatment and found that melatonin increased the LC3 levels, but attenuated the accumulation of p62, suggesting a stimulatory effect of melatonin on autophagy flux. Blockage of autophagy flux by chloroquine partially abolished the protective effects of melatonin, indicating that autophagy flux is involved in the protective effects of melatonin. Furthermore, we found that the AMPK/mTOR signaling pathway is involved in autophagy flux stimulation by melatonin. An in vivo study also illustrated that melatonin treatment ameliorated impaired wound healing in a streptozotocin-induced diabetic wound healing model. Thus, our study shows that melatonin protects EPCs against apoptosis and dysfunction via autophagy flux stimulation and ameliorates impaired wound healing in vivo, providing insight into its mechanism of action in diabetic wound healing.

Small molecule natural compound agonist of SIRT3 as a therapeutic target for the treatment of intervertebral disc degeneration.

Oxidative stress-induced mitochondrial dysfunction is implicated in the pathogenesis of intervertebral disc degeneration (IVDD). Sirtuin 3 (SIRT3), a sirtuin family protein located in mitochondria, is essential for mitochondrial homeostasis; however, the role of SIRT3 in the process of IVDD has remained elusive. Here, we explored the expression of SIRT3 in IVDD in vivo and in vitro; we also explored the role of SIRT3 in senescence, apoptosis, and mitochondrial homeostasis under oxidative stress. We subsequently activated SIRT3 using honokiol to evaluate its therapeutic potential for IVDD. We assessed SIRT3 expression in degenerative nucleus pulposus (NP) tissues and oxidative stress-induced nucleus pulposus cells (NPCs). SIRT3 was knocked down by lentivirus and activated by honokiol to determine its role in oxidative stress-induced NPCs. The mechanism by which honokiol affected SIRT3 regulation was investigated in vitro, and the therapeutic potential of honokiol was assessed in vitro and in vivo. We found that the expression of SIRT3 decreased with IVDD, and SIRT3 knockdown reduced the tolerance of NPCs to oxidative stress. Honokiol (10 µM) improved the viability of NPCs under oxidative stress and promoted their properties of anti-oxidation, mitochondrial dynamics and mitophagy in a SIRT3-dependent manner. Furthermore, honokiol activated SIRT3 through the AMPK-PGC-1α signaling pathway. Moreover, honokiol treatment ameliorated IVDD in rats. Our study indicated that SIRT3 is involved in IVDD and showed the potential of the SIRT3 agonist honokiol for the treatment of IVDD.

SIRT3 Activation by Dihydromyricetin Suppresses Chondrocytes Degeneration via Maintaining Mitochondrial Homeostasis.

Mitochondrial dysfunction is an important contributor to the development of osteoarthritis (OA). Sirtuin 3 (SIRT3) regulates diverse mitochondrial proteins to maintain mitochondrial homeostasis, and dihydromyricetin (DHM) is reported as a potential SIRT3 activator. This study aims to explore the relevance of SIRT3 and OA, as well as the therapeutic effects of DHM on mitochondrial homeostasis in TNF-α-treated chondrocytes. The relationship between SIRT3 and OA was confirmed by detecting SIRT3 level in vitro and in vivo. Mitochondrial dysfunction was evaluated in chondrocytes with or without SIRT3 knockdown. Furthermore, the effects of DHM on mitochondrial homeostasis were performed in TNF-α-treated rat chondrocytes in vitro. In this study, our results showed that the SIRT3 level was decreased in mouse OA cartilage, corresponding to the reduced SIRT3 level in TNF-α-treated chondrocytes in vitro. SIRT3 knockdown induced mitochondrial dysfunction in chondrocytes. Moreover, our study demonstrated that DHM might activate SIRT3 to protect rat chondrocytes from TNF-α-induced degeneration and protective effects of DHM on mitochondrial homeostasis in chondrocytes attributed to enhanced SIRT3. Collectively, SIRT3 deficiency is implicated in OA development and DHM exerts anti-degeneration effect by maintaining mitochondrial homeostasis via a SIRT3-dependent manner in chondrocytes.