Ferroptosis is a novel type of iron-dependent cell death driven by lipid peroxidation. More and more evidence shows that ferroptosis is related to various pathological conditions, such as neurodegenerative diseases, diabetic nephropathy, and cancer. Ferroptosis driven by lipid peroxidation may promote or inhibit the occurrence and development of these diseases. The intracellular antioxidant system plays an important role in resisting ferroptosis by inhibiting lipid peroxidation. The key pathways of ferroptosis include the amino acid metabolism pathway with SLC7A11-GPX4 as the key molecule, the iron metabolism pathway with ferritin or transferrin as the main component, and the lipid metabolism pathway. The occurrence of ferroptosis is regulated by intracellular proteins, which undergo various post-translational modifications, including ubiquitination. The ubiquitin-proteasome system (UPS) is one of the main degradation systems in cells. It catalyzes the ubiquitin molecule to label the protein and then the proteasome recognizes and degrades the target protein. UPS promotes ferroptosis by promoting the degradation of key ferroptosis molecules (such as SLC7A11, GPX4, and GSH) and antioxidant systems (such as NRF2). UPS can also inhibit ferroptosis by promoting the degradation of related molecules in the lipid metabolism pathway (such as ACLS4 and ALOX15). In this review, we summarize the latest research progress of ubiquitination modification in the regulation of ferroptosis, generalize the published studies on the regulation of ferroptosis by E3 ubiquitin ligase and deubiquitination, and sum up the targets of ubiquitin ligase and deubiquitination regulating ferroptosis, which is helpful to identify new prognostic indicators in human diseases and provide potential therapeutic strategies for these diseases.

Objective To explore the effect of shikonin on the recovery of nerve function after acute spinal cord injury(SCI)in rats.Methods 96 male Sprague-Dawley(SD)rats were divided into 4 groups randomly:sham operation group(Group A),sham operation+shikonin group(Group B),SCI+DMSO(Group C),SCI+shikonin group(Group D).The acute SCI model of rats was made by clamp method in groups C and D.After subdural catheterization,no drug was given in group A.rats in groups B and D were injected with 100 mg·kg-1 of shikonin through catheter 30 min after modeling,and rats in group C were given with the same amount of DMSO,once a day until the time point of collection tissue.Basso-Beattie-Bresnahan(BBB)scores were performed on 8 rats in each group at 6,12,and 3 d after moneling,and oblique plate tests were performed on 1,3,7 and 14 d after modeling,and then spinal cord tissues were collected.Eight rats were intraperitoneally injected with propidine iodide(PI)1 h before sacrificed to detection PI positive cells at 24 h in each group.Eight rats were sacrificed in each group at 24 h after modeling,the spinal cord injury was observed by HE staining.The Nissl staining was used to observe survivor number of nerve cells.Western-blot technique was used to detect the expression levels of Bcl-2 protein and apoptosis related protein RIPK1.Results After modeling,BBB scores were normal in group A and B,but in group C and D were significantly higher than those in group A and B.And the scores in group D were higher than those in group C in each time point(P＜0.05).At 12 h after modeling,the PI red stained cells in group D were significantly reduced compared with that in group C,and the disintegration of neurons was alleviated(P＜0.05).HE and Nissl staining showed nerve cells with normal morphology in group A and B at 24h after operation.The degree of SCI and the number of neuronal survival in group D were better than those in group C,the differ-ence was statistically significant at 24h(P＜0.05).The expression of Bcl-2 and RIPK1 proteins was very low in group A and B;The expression of RIPK1 was significantly increased in Group C and decreased in Group D,with a statistically significant dif-ference(P＜0.05);The expression of Bcl-2 protein in group D was significantly higher than that in group C(P＜0.05).Conclu-sion Shikonin can alleviate the pathological changes after acute SCI in rats,improve the behavioral score,and promote the re-covery of spinal nerve function.The specific mechanism may be related to the inhibition of TNFR/RIPK1 signaling pathway mediated necrotic apoptosis.

Activation of nuclear factor erythroid 2-related factor 2(Nrf2)by Kelch-like ECH-associated protein 1(Keap1)alkylation plays a central role in anti-inflammatory therapy.However,activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified.Deoxynyboquinone(DNQ)is a natural small molecule discovered from marine actinomycetes.The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1.DNQ exhibited signif-icant anti-inflammatory properties both in vitro and in vivo.The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be the α,β-unsaturated amides moieties by a chemical reaction between DNQ and N-acetylcysteine.DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway.Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation.The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry.DNQ triggered the ubiquitination and subsequent degra-dation of Keap1 by alkylation of the cysteine residue 489(Cys489)on Keap1-Kelch domain,ultimately enabling the activation of Nrf2.Our findings revealed that DNQ exhibited potent anti-inflammatory capacity through α,β-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain,suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies.

Background/Aims: Low educational attainment is a well-established risk factor for nonalcoholic fatty liver disease (NAFLD) in developed areas. However, the association between educational attainment and the risk of NAFLD is less clear in China. Methods: A cross-sectional study including over 200,000 Chinese adults across mainland China was conducted. Information on education level and lifestyle factors were obtained through standard questionnaires, while NAFLD and advanced fibrosis were diagnosed using validated formulas. Outcomes included the risk of NAFLD in the general population and high probability of fibrosis among patients with NAFLD. Logistic regression analysis was employed to estimate the risk of NAFLD and fibrosis across education levels. A causal mediation model was used to explore the potential mediators. Results: Comparing with those receiving primary school education, the multi-adjusted odds ratios (95% confidence intervals) for NAFLD were 1.28 (1.16 to 1.41) for men and 0.94 (0.89 to 0.99) for women with college education after accounting for body mass index. When considering waist circumference, the odds ratios (95% CIs) were 0.94 (0.86 to 1.04) for men and 0.88 (0.80 to 0.97) for women, respectively. The proportions mediated by general and central obesity were 51.00% and 68.04% for men, while for women the proportions were 48.58% and 32.58%, respectively. Furthermore, NAFLD patients with lower educational attainment showed an incremental increased risk of advanced fibrosis in both genders. Conclusions In China, a low education level was associated with a higher risk of prevalent NAFLD in women, as well as high probability of fibrosis in both genders.

Aim To clarify the effect of circulating exosomes on hypertension, screen out miRNAs which plays a key role, and explore its function.Methods The plasma exosomes of spontaneously hypertensive rats were extracted and injected into Sprague Dawley rats.The blood pressure changes of rats were detected.Plasma exosomes and exosomal RNA of hypertensive patients and SHR were extracted.Real time PCR was used to verify the expression changes of the selected 8 miRNAs; Western blot was used to detect the expression changes of LKB1 and PTEN protein levels in human umbilical vein endothelial cells transfected with miR-17-5p mimics.Results The plasma exosomes of SHRs significantly increased the blood pressure of SD rats(P<0.05).The expression of miR-17-5p and miR-218-5p in the plasma exosomes of hypertensive patients and SHRs both significantly increased.miR-17-5p inhibitors significantly attenuated the effect of SHR-exos on raising blood pressure.miR-17-5p mimics down-regulated the expression of LKB1 and PTEN in HUVECs cultured in vitro.Conclusions The plasma exosomes of SHR can significantly increase blood pressure of Sprague Dawley rats.miR-17-5p may be the key miRNA.exo-miR-17-5p may promote the occurrence and development of hypertension by regulating the LKB1/PTEN signal.

Aim To investigate the effect of Mahuang-Dahuang(MD)on inhibiting M1 polarization of alveolar macrophages, alleviating inflammatory injury and treating acute lung injury, and the underlying mechanism.Methods Abandoned rats were divided into normal control group(NC), model control group(MC), MD high-dose group(MD-H), medium-dose group(MD-M), low-dose group(MD-L), and DXMS group.Lipopolysaccharide(LPS)was injected intraperitoneally to prepare an acute lung injury(ALI)rat model.After the model was established, different doses of MD were administered by intragastric administration, and the pathological changes of lung tissues were observed; immunohistochemical method was used to detect the expression of alveolar macrophage marker F4/80,F4/80 and CD80, CD80 and IL-6 Co-expression; Flow cytometry was used to detect the content of F4/80 and CD80 in lung tissues; PCR was used to detect the relative expression of IL-6, INOS, TNF-α mRNA in lung tissues; Western blot was used to detect lung tissue CCR2, CCL2, p-p65, P65, p-p38MAPK, p38MAPK protein expression.Results Compared with NC group, rats in MC group had damaged alveolar structure, thickened pulmonary interstitial edema, and infiltrated a large number of inflammatory cells.Among them, the number of macrophages increased significantly, which promoted the increase in the expression of macrophages-related chemokines CCR2 and CCL2.The number and expression of M1 alveolar macrophages in lung tissues increased, the relative expression of M1 alveolar macrophages-related cytokines IL-6, INOS and TNF-α mRNA was up-regulated, and the target protein in the related pathways of alveolar macrophages M1 polarization p-NF-κBp65/NF-κBp65, p-P38MAPK/p38MAPK protein expression was up-regulated.Compared with MC group, the pathological status of lung tissues in MD high, medium, and low dose groups was significantly improved, the number of lung tissue M1 alveolar macrophages decreased, the relative expression of inflammatory factors IL-6, INOS and TNF-α mRNA was down-regulated, and the protein expression of CCR2, CCL2, p-NF-κBp65/ NF-κBp65 and p-P38MAPK/p38MAPK was reduced in lung tissues.Conclusions MD can inhibit the M1 polarization of alveolar macrophages, reduce the activation and release of inflammatory factors, inhibit inflammatory response, and prevent acute lung injury by regulating the expression of related indicators of NF-κB and MAPK signaling pathways.

OBJECTIVE: This study aims to investigate the association of metabolic phenotypes that are jointly determined by body mass index (BMI) or fat mass percentage and metabolic health status with the ten-year risk of cardiovascular disease (CVD) among Chinese adults. METHODS: Data were obtained from a cross-sectional study. BMI and body fat mass percentage (FMP) combined with the metabolic status were used to define metabolic phenotypes. Multiple linear regression and logistic regression were used to examine the effects of metabolic phenotypes on CVD risk. RESULTS: A total of 13,239 adults aged 34-75 years were included in this study. Compared with the metabolically healthy non-obese (MHNO) phenotype, the metabolically unhealthy non-obese (MUNO) and metabolically unhealthy obese (MUO) phenotypes defined by BMI showed a higher CVD risk [odds ratio, OR (95% confidence interval, CI): 2.34 (1.89-2.89), 3.45 (2.50-4.75), respectively], after adjusting for the covariates. The MUNO and MUO phenotypes defined by FMP showed a higher CVD risk [ OR (95% CI): 2.31 (1.85-2.88), 2.63 (1.98-3.48), respectively] than the MHNO phenotype. The metabolically healthy obese phenotype, regardless of being defined by BMI or FMP, showed no CVD risk compared with the MHNO phenotype. CONCLUSION General obesity without central obesity does not increase CVD risk in metabolically healthy individuals. FMP might be a more meaningful factor for the evaluation of the association of obesity with CVD risk. Obesity and metabolic status have a synergistic effect on CVD risk.
Adipose Tissue/anatomy & histology* ; Adult ; Aged ; Body Mass Index ; Cardiovascular Diseases/etiology* ; China/epidemiology* ; Cross-Sectional Studies ; Female ; Humans ; Male ; Metabolic Diseases/etiology* ; Middle Aged ; Obesity/complications* ; Phenotype ; Regression Analysis ; Risk Factors

Lung and intestine combination therapy(LICT) is effective in the treatment of acute lung injury(ALI). In this study, the combination of Mahuang Decoction and Dachengqi Decoction(hereinafter referred to as the combination), a manifestation of LICT, was employed to explore the effect of nuclear factor kappaB(NF-κB)/nucleotide binding oligomerization domain-like receptors-3(NLRP3) pathway and alveolar macrophage activation on the lung inflammation in rats with ALI, for the purpose of elucidating the mechanism of LICT in treating ALI. After the modeling of ALI with limpolysaccharide(LPS, ip), rats were respectively given(ig) the combination at 10, 7.5, and 5 g·kg~(-1)(high-dose, medium-dose, and low-dose LICT groups, separately), once every 8 h for 3 times. Haematoxylin-eosin(HE) staining was used to observe the histopathological changes of lung tissue, followed by the scoring of inflammation. Immunohistochemistry was applied to detect alveolar macrophage activation, enzyme-linked immunosorbent assay(ELISA) was applied to detect the serum content of tumor necrosis factor-α(TNF-α) and interleukin-18(IL-18), Western blot was applied to detect the protein expression of phosphorylated-nuclear factor kappaB p65(p-NF-κB p65), nuclear factor kappaB p65(NF-κB p65), phosphorylated-inhibitor kappaB alpha(p-IκBα), inhibitor kappaB alpha(IκBα), and NLRP3 in lung tissue, and quantitative reverse transcription-PCR(qRT-PCR) was applied to detect the mRNA expression of TNF-α, IL-18, NLRP3, and NF-κB p65 in lung tissue. The results showed that LICT groups demonstrated lung injury relief, decrease in inflammation score, alleviation of alveolar macrophage activation, significant decline in serum content of inflammatory factors TNF-α and IL-18, and decrease of the protein expression of p-NF-κB p65/NF-κB p65, p-IκBα/IκBα, and NLRP3, and mRNA expression of TNF-α, IL-18, NLRP3, and NF-κB p65 in lung tissue. In summary, LICT has definite therapeutic effect on ALI. The mechanism is that it inhibits alveolar macrophage activation by suppressing NF-κB/NLRP3 signaling pathway, thereby reducing the activation and release of inflammatory factors and finally inhibiting inflammation.
Acute Lung Injury/genetics* ; Animals ; Drugs, Chinese Herbal ; Intestines ; Lipopolysaccharides ; Lung/metabolism* ; Macrophage Activation ; NF-kappa B/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Rats ; Signal Transduction

OBJECTIVES: To study the role and mechanism of autophagy in lipopolysaccharide (LPS)-induced inflammatory response of human alveolar epithelial A549 cells. METHODS: A549 cells were stimulated with LPS to establish a cell model of inflammatory response, and were then grouped (n=3 each) by concentration (0, 1, 5, and 10 μg/mL) and time (0, 4, 8, 12, and 24 hours). The A549 cells were treated with autophagy inhibitor 3-methyladenine (3-MA) to be divided into four groups (n=3 each): control, LPS, 3-MA, and 3-MA+LPS. The A549 cells were treated with autophagy agonist rapamycin (RAPA) to be divided into four groups (n=3 each): control, LPS, RAPA, and RAPA+LPS. The A549 cells were transfected with the Toll-like receptor 4 (TLR4) overexpression plasmid to be divided into four groups (n=3 each): TLR4 overexpression control, TLR4 overexpression, TLR4 overexpression control+LPS, and TLR4 overexpression+LPS. The A549 cells were transfected with TLR4 siRNA to be divided into four groups (n=3 each): TLR4 silencing control,TLR4 silencing, TLR4 silencing control+LPS, and TLR4 silencing+LPS. CCK-8 assay was used to measure cell viability. Western blot was used to measure the protein expression levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4. RESULTS: After stimulation with 1 μg/mL LPS for 12 hours, the levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4 increased and reached the peak (P<0.05). Compared with the LPS group, the 3-MA+LPS group had reduced expression of autophagy-related proteins and increased expression of inflammation-related proteins and TLR4, while the RAPA+LPS group had increased expression of autophagy-related proteins and reduced inflammation-related proteins and TLR4 (P<0.05). The TLR4 overexpression+LPS group had reduced autophagy-related proteins and increased inflammation-related proteins compared with the TLR4 overexpression control+LPS group, and the TLR4 silencing+LPS group had increased autophagy-related proteins and reduced inflammation-related proteins compared with the TLR4 silencing control+LPS group (P<0.05). CONCLUSIONS In the LPS-induced inflammatory response of human alveolar epithelial A549 cells, autophagic flux has a certain protective effect on A549 cells. TLR4-mediated autophagic flux negatively regulates the LPS-induced inflammatory response of A549 cells.
Humans ; A549 Cells ; Autophagy ; Beclin-1/metabolism* ; Caspase 1/metabolism* ; Inflammation ; Lipopolysaccharides/pharmacology* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Toll-Like Receptor 4/metabolism*