[Bushen Huoxue Fang improves recurrent miscarriage in mice by down-regulating the JAK2/STAT3 pathway]

OBJECTIVE

To investigate the efficacy of Bushen Huoxue Fang (BSHXF, a traditional Chinese medicine formula) for improving recurrent spontaneous abortion (RSA) in mice and the role of tyrosine kinase (JAK2) and transcriptional activator (STAT3) signaling pathway in its therapeutic mechanism.

METHODS

Female CBA/J mice were caged with male DBA/2 mice to establish RSA mouse models, which were randomly divided into model group, dydrogesterone group and BSHXF group, with the female mice caged with male BALB/c mice as the control group (n=6). From the first day of pregnancy, the mice were subjected to daily intragastric administration of BSHXF, dydrogesterone, or distilled water (in control and model groups) for 12 days. After the treatments, serum levels of antithrombin III (AT-III), activated protein C (APC), tissue plasminogen activator (t-PA), progesterone, human chorionic gonadotropin (HCG), and estradiol (E2) were detected in each group using ELISA. HE staining was used to observe the morphological changes of the endometrium of the mice. Western blotting was performed to determine the expressions of p-JAK2, p-Stat3 and Bcl-2 in the placenta of the mice.

RESULTS

Compared with the control mice, the mouse models of RSA showed a significantly increased embryo loss rate with decreased serum levels of AT-III, T-PA, progesterone, APC and HCG, increased placental expressions of p-JAK2, p-STAT3 and Bax, and decreased expression of Bcl-2 (P < 0.05). Treatments with BSHXF and dydrogesterone both increased serum levels of AT-III, t-PA and HCG in the mouse models; Serum APC level was significantly reduced in BSHXF group and serum progesterone level was significantly increased in dydrogesterone group (P < 0.05).

CONCLUSION

BSHXF can improve the prethrombotic state and inhibit cell apoptosis by downregulating the JAK2/STAT3 pathway to increase the pregnancy rate in mouse models of RSA.

The role of mitochondrial fission in intervertebral disc degeneration

Low back pain (LBP) is an extremely common disorder and is a major cause of disability globally. Intervertebral disc degeneration (IVDD) is the main contributor to LBP. Nevertheless, the specific mechanisms underlying the pathogenesis of IVDD remain unclear. Mitochondria are highly dynamic organelles that continuously undergo fusion and fission, known as mitochondrial dynamics. Accumulating evidence has revealed that aberrantly activated mitochondrial fission leads to mitochondrial fragmentation and dysfunction, which are involved in the development and progression of IVDD. To date, research into mitochondrial dynamics in IVDD is at an early stage. The present narrative review aims to summarize the most recent findings about the role of mitochondrial fission in the pathogenesis of IVDD.

Identification of novel characteristic biomarkers and immune infiltration profile for the anaplastic thyroid cancer via machine learning algorithms

PURPOSE

Anaplastic thyroid cancer (ATC) is a rare and lethal malignant cancer. In recent years, the application of molecular-driven targeted therapy and immunotherapy has markedly improved the prognosis of ATC. This study aimed to identify characteristic genes for ATC diagnosis and revealed the role of ATC characteristic genes in drug sensitivity and immune cell infiltration.

METHODS

We downloaded ATC RNA-sequencing data from the GEO database. Following the combination and normalization of the dataset, we first divided the combined datasets into the training cohort and the validation cohort. We identified differentially expressed genes (DEGs) in ATC by differential expression analysis in the training cohort. We used two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) to identify ATC characteristic genes. The CIBERSORT algorithm was performed to calculate the abundance of various immune cells in ATC. Finally, we validated the expression of ATC characteristic genes by quantitative RT-PCR (RT-qPCR) in ATC cell lines and immunohistochemistry (IHC).

RESULTS

A total of 425 DEGs were identified in the training cohort, including 240 upregulated genes and 185 downregulated genes. Four ATC characteristic genes (ADM, PXDN, MMP1, and TFF3) were identified, and their diagnostic value was validated in the validation cohort (AUC in ROC analysis > 0.75). We established a practical gene expression-based nomogram to accurately predict the probability of ATC. We also found that ATC characteristic biomarkers are associated with the tumor immune microenvironment and drug sensitivity.

CONCLUSION

ADM, PXDN, MMP1, and TFF3 might serve as potential ATC diagnostic biomarkers and may be helpful for ATC molecular targeted therapy and immunotherapy.

Effects of electroacupuncture on the kisspeptin-gonadotropin-releasing hormone (GnRH) /luteinizing hormone (LH) neural circuit abnormalities and androgen receptor expression of kisspeptin/neurokinin B/dynorphin neurons in PCOS rats

BACKGROUND

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, anovulation, and polycystic ovaries. Electroacupuncture (EA) can effectively improve hyperandrogenism and increase ovulation frequency in patients with PCOS. Pieces of suggest that androgen activity in the brain is associated with impaired steroid negative feedback in such patients. Studies have shown that EA regulated androgen receptor (AR) expression and local factor levels (such as anti-Müllerian hormone and inhibin B) in the ovary of PCOS rats. However, few studies have explored the effect of EA on androgen activity in the brain.

OBJECTIVE

This study investigated the effect of EA on the kisspeptin-gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) neural circuit and sex hormone receptor expression in the hypothalamus of PCOS rats.

METHODS

PCOS signs were induced by letrozole administration, and the induced rats were treated with low-frequency EA at Guan Yuan acupoint (CV4). The effect of EA on PCOS-like signs was evaluated by observing changes in the body weight, ovarian quality, ovarian morphology, and serum sex hormone levels in rats. To explore the mechanism of the effect of EA on PCOS-like signs, the neuropeptide content of the kisspeptin-GnRH/LH neural circuit was assessed using enzyme-linked immunosorbent assay(ELISA); AR and estrogen receptor α (ERα) coexpression on kisspeptin/neurokinin B/dynorphin (KNDy) neurons was determined via triple-label immunofluorescence; and protein and mRNA expression of Kiss1, Ar, Esr1, and kisspeptin receptor (Kiss1r) was evaluated via western blotting and Reverse Transcription-Polymerase Chain Reaction (RT-PCR).

RESULTS

The results revealed that the estrous cycle of rats in the EA treatment group recovered, and their body and ovary weight reduced; ovarian morphology improved; serum testosterone and LH levels significantly decreased; and kisspeptin, GnRH, and dynorphin levels in hypothalamic arcuate nucleus significantly decreased. Compared with controls, the number of AR/Kiss1-positive cells increased, number of ERα/Kiss1-positive cells decreased, and protein and mRNA expression of Kiss1, Ar, and Kiss1r significantly increased in PCOS rats. However, EA treatment reversed these changes and reduced the expression of Kiss1, Ar, and Kiss1r significantly.

CONCLUSION

Improvement in the reproductive hallmarks of PCOS rats via EA may be achieved by regulating the kisspeptin-GnRH/LH circuit via androgen activity attenuation. Thus, the results provide an experimental basis for acupuncture as an adjuvant medical therapy on PCOS.

Ultrasensitive Lateral Flow Immunoassay for Fumonisin B1 Detection Using Highly Luminescent Aggregation-Induced Emission Microbeads

Lateral flow immunoassay (LFIA) based on fluorescent microbeads has attracted much attention for its use in rapid and accurate food safety monitoring. However, conventional fluorescent microbeads are limited by the aggregation-caused quenching effect of the loaded fluorophores, thus resulting in low signal intensity and insufficient sensitivity of fluorescent LFIA. In this study, a green-emitting fluorophore with an aggregation-induced emission (AIE) characteristic was encapsulated in polymer nanoparticles via an emulsification technique to form ultrabright fluorescent microbeads (denoted as AIEMBs). The prepared AIEMBs were then applied in a competitive LFIA (AIE-LFIA) as signal reporters for the rapid and highly sensitive screening of fumonisin B1 (FB1) in real corn samples. High sensitivity with a detection limit of 0.024 ng/mL for FB1 was achieved by the developed AIE-LFIA. Excellent selectivity, good accuracy, and high reliability of the AIE-LFIA were demonstrated, indicating a promising platform for FB1 screening.

Genome-Wide mRNA and Long Non-Coding RNA Analysis of Porcine Trophoblast Cells Infected with Porcine Reproductive and Respiratory Syndrome Virus Associated with Reproductive Failure

Porcine reproductive and respiratory syndrome (PRRS) is a vertically transmitted reproductive disorder that is typically characterized by miscarriage, premature birth, and stillbirth in pregnant sows after infection. Such characteristics indicate that PRRSV can infect and penetrate the porcine placental barrier to infect fetus piglets. The porcine trophoblast is an important component of the placental barrier, and secretes various hormones, including estrogen and progesterone, to maintain normal pregnancy and embryonic development during pregnancy. It is conceivable that the pathogenic effects of PRRSV infection on porcine trophoblast cells may lead to reproductive failure; however, the underlying detailed mechanism of the interaction between porcine trophoblast (PTR2) cells and PRRSV is unknown. Therefore, we conducted genome-wide mRNA and long non-coding RNA (lncRNA) analysis profiling in PRRSV-infected PTR2. The results showed that 672 mRNAs and 476 lncRNAs were significantly different from the control group after viral infection. Target genes of the co-expression and co-location of differential mRNAs and lncRNAs were enriched by GO (gene ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis, revealing that most of the pathways were involved in cell nutrient metabolism, cell proliferation, and differentiation. Specifically, the estrogen signaling pathway, the PI3K (PhosphoInositide-3 Kinase)-Akt (serine/threonine kinase) signaling pathway, and the insulin secretion related to embryonic development were selected for analysis. Further research found that PRRSV inhibits the expression of G-protein-coupled estrogen receptor 1 (GPER1), thereby reducing estrogen-induced phosphorylation of AKT and the mammalian target of rapamycin (mTOR). The reduction in the phosphorylation of AKT and mTOR blocks the activation of the GPER1- PI3K-AKT-mTOR signaling pathway, consequently restraining insulin secretion, impacting PTR2 cell proliferation, differentiation, and nutrient metabolism. We also found that PRRSV triggered trophoblast cell apoptosis, interrupting the integrity of the placental villus barrier. Furthermore, the interaction network diagram of lncRNA, regulating GPER1 and apoptosis-related genes, was constructed, providing a reference for enriching the functions of these lncRNA in the future. In summary, this article elucidated the differential expression of mRNA and lncRNA in trophoblast cells infected with PRRSV. This infection could inhibit the PI3K-AKT-mTOR pathway and trigger apoptosis, providing insight into the mechanism of the vertical transmission of PRRSV and the manifestation of reproductive failure.

Number of Teeth and Denture Use Are Associated with Frailty among Chinese Older Adults: A Cohort Study Based on the CLHLS from 2008 to 2018

OBJECTIVES

The aim of this study was to determine the association between oral health and the development of frailty over a 10-year period in older Chinese adults.

DESIGN

This was a cohort study.

SETTING AND PARTICIPANTS

The data in this study were derived from the 2008, 2011, 2014 and 2018 waves of the Chinese Longitudinal Health Longevity Survey (CLHLS). The final analysis included 1155 older adults who had complete data for the Frailty Index (FI) and the other factors(oral health, sociodemographics, etc) that were analyzed in the study.

MEASUREMENTS

Frailty was assessed by the FI, which consists of 40 deficits(self-health assessments, diseases, physical functions,etc). Multivariable logistic regression was carried out to calculate the odds ratios (ORs) of the independent variables,which were obtained from investigator surveys and self-reports, in association with the development of frailty.

RESULTS

The prevalence of frailty at baseline was 22.94%, and the 10-year incidence of frailty was 24.16% (215/890). Age, number of natural teeth, use of dentures, toothache and sex were independent risk factors for frailty at baseline. After full adjustment, multivariate logistic regression analysis indicated that compared with having ≥21 teeth, edentulism (ORs 3.575; 95% CI 2.095,6.101) and partial tooth loss (ORs 2.448; 95% CI 1.592,3.766) were associated with progression to frailty. Compared with those with ≥21 teeth, those with <21 teeth and without dentures (ORs 2.617; 95% CI 1.713,3.999) were more likely to progress to frailty.

CONCLUSION

The loss of natural teeth is associated with the progression of frailty in older Chinese adults and denture using can help lower the odds of being frailty. Further research on maintain natural teeth and the appropriate use of dentures may help to establish effective frailty prevention strategies for the older adults.

[Research advances on the treatment of diabetic foot ulcers with autologous platelet-rich fibrin]

Diabetic foot is one of the serious complications of diabetic patients, which makes the society and public health bear a huge economic burden. In recent years, more and more studies at home and abroad have been conducted on the treatment of chronic wounds with autologous platelet-rich fibrin, and the therapeutic concepts and methods have been updated constantly. In this paper, we reviewed the general situation of autologous platelet-rich fibrin, the mechanism of autologous platelet-rich fibrin in promoting the healing of diabetic foot ulcers and the new progress in its application, so as to provide a new strategy for the repair of diabetic foot ulcers.

Laparoscopic myomectomy for posterior cervical myoma: authors' experience and strategy

OBJECTIVES

Posterior cervical myoma poses a challenge for gynecologic surgeons, especially in women who want to preserve their fertility. The objective of this study is to summarize our experience with and strategy for this difficult situation.

METHODS

Between July 2019 and June 2021, 13 patients with posterior cervical myoma underwent laparoscopic myomectomy in our department. In addition to using the conventional strategy for laparoscopic myomectomy, other measures such as uterine suspension and preliminary exposure of vital structures, including the uterine artery and ureter, were implemented to enhance safety and improve efficacy. The perioperative outcomes for these patients were retrospectively evaluated.

RESULTS

All surgeries were completed successfully with no conversion to laparotomy. There were no intraoperative complications or needs for blood transfusion. Uterine suspension was performed in all cases, while preliminary exposure of the uterine artery and ureter was performed in nine cases (69.2%). Uterine artery ligation was necessary in two cases. The mean surgical duration was 78.5 ± 12.3 minutes, mean blood loss was 54.2 ± 11.9 mL, and the mean specimen weight was 171.5 ± 59.8 g. Histopathologic analysis revealed leiomyomas in all cases. The postoperative course and follow-up were uneventful.

CONCLUSION

By uterine suspension and preliminary exposure of vital structures, including the uterine artery and ureter, laparoscopic myomectomy for posterior cervical myoma can be performed safely.

[The influence of two kinds of transnasal endoscopic surgery on the outcome status of sinus cavity in patients with eosinophilic chronic rhinosinusitis with nasal polyps]

Objective: To investigate the trend of postoperative cavity status in patients with eosinophilic chronic sinusitis with nasal polyps (eCRSwNP) who underwent total nasalization surgery and partial reboot surgery. And to discuss the relationship between tissue eosinophil counts and status of postoperative cavity. Methods: Patients with eCRSwNP in four tertiary medical centers (Longgang ENT Hospital, Xiamen Humanity Hospital, Guangdong Clifford Hospital and the First Affiliated Hospital of Sun Yat-Sen University) from March 2018 to October 2021 were divided into 2 groups. The group without previous surgery history was performed for the nasalization surgery, and another group with previous surgery history underwent the part-reboot surgery. The follow-up time after operation was defined as the following 5 stages: 6, 12, 20-24, 36 and more than 42 months. According to FESS-95 Guangzhou standard, status of sinus cavity was assessed and classified into 3 categories: good, better and bad. The association between the sinus cavity status and tissue eosinophil counts in the above 5 stages was analyzed by one-way ANOVA, and P<0.05 was considered statistically significant. Results: A total of 72 eCRSwNP patients finished the follow-up in this study. There were 47 males and 25 females in these patients, aged from 11 to 67 years. A total of 50 cases underwent nasalization surgery and 22 cases underwent partial reboot surgery. With the follow-up time from 6 to 48 months, there were 72 cases (100.0%) who completed 6 months and 12 months follow up, 46 cases (63.9%) for 20-24 months, 36 cases (50.0%) for 32-36 months and 16 cases (22.2%) with the follow-up time more than 42 months. No matter what kind of surgery, there was no "bad" situation of the surgical cavity status 6 months after the operation, and the differentiation gradually occurred more than 12 months after the surgery. Moreover, the rates of "good" cavity status for the 5 stages in the group of nasalization surgery were 78.0%, 66.0%, 56.7%, 47.6% and 42.9%, and were 63.6%, 45.5%, 25.0%, 20.0% and 11.1% in the partial reboot surgery group, respectively, suggesting that the status of nasal cavity in nasalization surgery group was always better than that in partial reboot surgery group in every period. In addition, the "bad" rate was 0, 8.0%, 10.0%, 14.3% and 28.6% in the group of nasalization surgery, and was 0, 27.3%, 18.8%, 33.3% and 55.6% in the partial reboot surgery group, respectively. The average percentage of tissue eosinophil counts in the 72 cases was 42.1%, which had no obvious effect on the status of the surgical cavity (P>0.05). Conclusions: For eCRSwNP patients, the operative cavity status in the patients without previous operation history treated with nasalization surgery is good. The time of 1-2 years after surgery is the main period for sinus lesions. The counts of tissue eosinophils has no significant influence on surgical sinus cavity status in the eCRSwNP patients.

TRPM8 deficiency attenuates liver fibrosis through S100A9-HNF4α signaling

Background

Liver fibrosis represent a major global health care burden. Data emerging from recent advances suggest TRPM8, a member of the transient receptor potential (TRP) family of ion channels, plays an essential role in various chronic inflammatory diseases. However, its role in liver fibrosis remains unknown. Herein, we assessed the potential effect of TRPM8 in liver fibrosis.

Methods

The effect of TRPM8 was evaluated using specimens obtained from classic murine models of liver fibrosis, namely wild-type (WT) and TRPM8^−/− (KO) fibrotic mice after carbon tetrachloride (CCl₄) or bile duct ligation (BDL) treatment. The role of TRPM8 was systematically evaluated using specimens obtained from the aforementioned animal models after various in vivo and in vitro experiments.

Results

Clinicopathological analysis showed that TRPM8 expression was upregulated in tissue samples from cirrhosis patients and fibrotic mice. TRPM8 deficiency not only attenuated inflammation and fibrosis progression in mice but also helped to alleviate symptoms of cholangiopathies. Moreover, reduction in S100A9 and increase in HNF4α expressions were observed in liver of CCl₄- and BDL- treated TRPM8^−/− mice. A strong regulatory linkage between S100A9 and HNF4α was also noticed in L02 cells that underwent siRNA-mediated S100A9 knockdown and S100A9 overexpressing plasmid transfection. Lastly, the alleviative effect of a selective TRPM8 antagonist was confirmed in vivo.

Conclusions

These findings suggest TRPM8 deficiency may exert protective effects against inflammation, cholangiopathies, and fibrosis through S100A9-HNF4α signaling. M8-B might be a promising therapeutic candidate for liver fibrosis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-022-00789-4.

DOCK4 regulates ghrelin production in gastric X/A-like cells

PURPOSE

Ghrelin, a gastric hormone, provides a hunger signal to the central nervous system to stimulate food intake. Ghrelin also modulates neuroinflammatory and apoptotic processes. Dedicator of cytokinesis 4 (DOCK4), a guanine nucleotide exchange factor (GEF), is involved in the regulation of neuronal polarization and axon regeneration. However, the effect of DOCK4 on ghrelin production has not been explored.

METHODS

The expression of DOCK4 in human and mouse stomach was examined by immunohistochemical staining. The synthesis and secretion of ghrelin in Dock4 null mice were evaluated by real-time quantitative PCR, Western blot and ELISA. The effects of DOCK4 on ghrelin production in mHypoE-42 cells were measured by real-time quantitative PCR and Western blot.

RESULTS

We showed that DOCK4 was expressed in both human and mouse gastric ghrelin cells. The mRNA and protein levels of gastric ghrelin, as well as ghrelin secretion, were remarkably diminished in Dock4 null mice. Furthermore, we showed that overexpression of Dock4 significantly stimulated ghrelin expression, while siRNA knockdown of endogenous Dock4 resulted in a marked decrease of ghrelin in mHypoE-N42 cells.

CONCLUSIONS

Our results identify DOCK4 as a critical regulator for ghrelin production in gastric X/A-like cells.

Hypersensitive C-reactive protein-albumin ratio is associated with stroke-associated pneumonia and early clinical outcomes in patients with acute ischemic stroke

OBJECTIVES

We aimed to explore the association between the baseline hypersensitive C-reactive protein-albumin ratio (CAR) and stroke-associated pneumonia (SAP) during hospitalization and the short-term prognosis in patients with acute ischemic stroke (AIS).

METHODS

We enrolled 766 patients with AIS and collected their admission baseline characteristics, including their National Institutes of Health Stroke Scale score, CAR, age, atrial fibrillation, dysphagia, sex, stroke severity (A² DS² ) score, and other information. The occurrence of SAP within 7 days after stroke, length of hospital stay, and physical condition at discharge were also recorded. The patients' Modified Rankin Scale (mRS) scores and mortality 3 months after AIS were further evaluated at follow-up. All patients were divided into four groups based on the quartiles of the admission CAR (Q1 <1.3, Q2 1.3-3.7, Q3 3.7-9.3, Q4 ≥9.3).

RESULTS

During hospitalization, 92 (11.9%) patients were diagnosed with SAP. The patients with SAP had a higher CAR than the non-SAP patients (p < .001). In the multivariate-adjusted model, the patients in the Q3 and Q4 groups had a higher SAP risk (aOR was 5.21 and 17.72, p-trend < .001) than those in the lowest quartile. The area under the curve for the CAR's ability to predict SAP was 0.810 in the receiver operating characteristic curve analysis and had a similar predictive efficacy as the A² DS²  score (p <.05). The length of stay in the SAP group was almost the same as that in the non-SAP group, but the clinical outcomes were worse at discharge and at the 3-month follow-up in the SAP group. In addition, the patients in the higher CAR quartiles at admission were more likely to have poorer clinical outcomes.

CONCLUSIONS

Patients with AIS with a high CAR at admission are more likely to develop SAP during hospitalization and have poor short-term clinical outcomes. These findings might help to timely identify patients at high risk of SAP and provide a basis for further research on prophylactic antibiotic therapy.

Establishment of a Real-Time Quantitative PCR Assay for Porcine Circovirus-Like Virus and the First Evidence of Its Spread to Hainan and Jiangxi Provinces of China

Porcine Circovirus-like (PCL) virus, a new emerging virus, has been widely detected in Guangdong, Guangxi, and Anhui provinces in China, which may be a novel agent causing severe diarrhea in newborn piglets and tending to spread widely. Evidence suggests that the virus is related to hemorrhagic enteritis and diarrhea, and many newborn piglets were emaciated to death after infection. Therefore, a sensitive, quick, and accurate detection system for virus detection and epidemiological investigation is necessary. In this study, we developed a real-time quantitative PCR assay based on SYBR green for the detection of PCL virus. The ORF4 conserved region of PCL virus was found by the alignment of the uploaded genome sequences to design specific primers, and the primers were tested and showed good specificity, sensitivity, and reproducibility. Approximately, 138 fecal samples were obtained from diarrheal pigs in South China from June to December 2021. Approximately, 22.46% (31/138) of the samples and 40% (8/20) of the pig farms were positive for PCL virus, respectively, by using this method. Moreover, it is worth noting that the virus was first detected in Hainan and Jiangxi Provinces of China, which means that the virus may spread widely in China. Through evolutionary tree analysis and partial sequence comparison, there are some differences of virus genes in each province, suggesting that there is a risk of variation, and the four PCL virus strains showed a sequence similarity of 86.7%–87.8% for the rep gene and 92.2%–92.9% for the Rep protein, respectively, with Bo-Circo-like virus that is detected in bovine, which further demonstrates a close relationship between the two viruses that originated from different animals. In conclusion, our study provides a useful diagnostic approach to PCL virus detection and epidemiological inquiry. Meanwhile, the epidemic data using this real-time qPCR assay provide evidence for the widespread variations and epidemic of the virus in South China, and warn the appropriate measures for prevention, and control of porcine circovirus-like virus infection should be under consideration in pig production.

Reciprocal regulation of NRF2 by autophagy and ubiquitin-proteasome modulates vascular endothelial injury induced by copper oxide nanoparticles

NRF2 is the key antioxidant molecule to maintain redox homeostasis, however the intrinsic mechanisms of NRF2 activation in the context of nanoparticles (NPs) exposure remain unclear. In this study, we revealed that copper oxide NPs (CuONPs) exposure activated NRF2 pathway in vascular endothelial cells. NRF2 knockout remarkably aggravated oxidative stress, which were remarkably mitigated by ROS scavenger. We also demonstrated that KEAP1 (the negative regulator of NRF2) was not primarily involved in NRF2 activation in that KEAP1 knockdown did not significantly affect CuONPs-induced NRF2 activation. Notably, we demonstrated that autophagy promoted NRF2 activation as evidenced by that ATG5 knockout or autophagy inhibitors significantly blocked NRF2 pathway. Mechanically, CuONPs disturbed ubiquitin–proteasome pathway and consequently inhibited the proteasome-dependent degradation of NRF2. However, autophagy deficiency reciprocally promoted proteasome activity, leading to the acceleration of degradation of NRF2 via ubiquitin–proteasome pathway. In addition, the notion that the reciprocal regulation of NRF2 by autophagy and ubiquitin–proteasome was further proven in a CuONPs pulmonary exposure mice model. Together, this study uncovers a novel regulatory mechanism of NRF2 activation by protein degradation machineries in response to CuONPs exposure, which opens a novel intriguing scenario to uncover therapeutic strategies against NPs-induced vascular injury and disease.

CuONPs exposure activates NRF2 signaling in vascular endothelial cells and mouse thoracic aorta.

KEAP1 is dispensable for NRF2 activation in CuONPs-treated vascular endothelial cells.

CuONPs-induced autophagy facilitates NRF2 activation in vascular endothelial cells and mouse thoracic aorta.

Autophagy and ubiquitin–proteasome reciprocally regulate NRF2 activation in CuONPs-treated vascular endothelial cells and mouse thoracic aorta.