With the acceleration of aging society, delaying aging or promoting healthy aging has become a major demand for human health. 5-Lipoxygenase (5-LOX) is a key enzyme catalyzing arachidonic acid into leukotrienes (LTs), which is a potent mediator of the inflammatory response. Previous studies showed that abnormal activation of 5-LOX and overproduction of LTs are closely related to the occurrence and development of aging-related inflammatory diseases. Therefore, inhibiting 5-LOX activation is a possibly potential strategy for treating age-related diseases. In this paper, the latest research progress in 5-LOX activation, 5-LOX in mediating aging-related diseases and its small molecule inhibitors is briefly reviewed to provide scientific theoretical basis and new ideas for the prevention and treatment of aging-related inflammatory diseases.
Humans ; Arachidonate 5-Lipoxygenase ; Leukotrienes ; Arachidonic Acid ; Aging ; Lipoxygenase Inhibitors/pharmacology*

Glioblastoma is the most common primary cranial malignancy, and chemotherapy remains an important tool for its treatment. Sanggenon C(San C), a class of natural flavonoids extracted from Morus plants, is a potential antitumor herbal monomer. In this study, the effect of San C on the growth and proliferation of glioblastoma cells was examined by methyl thiazolyl tetrazolium(MTT) assay and 5-bromodeoxyuridinc(BrdU) labeling assay. The effect of San C on the tumor cell cycle was examined by flow cytometry, and the effect of San C on clone formation and self-renewal ability of tumor cells was examined by soft agar assay. Western blot and bioinformatics analysis were used to investigate the mechanism of the antitumor activity of San C. In the presence of San C, the MTT assay showed that San C significantly inhibited the growth and proliferation of tumor cells in a dose and time-dependent manner. BrdU labeling assay showed that San C significantly attenuated the DNA replication activity in the nucleus of tumor cells. Flow cytometry confirmed that San C blocked the cell cycle of tumor cells in G_0/G_1 phase. The soft agar clone formation assay revealed that San C significantly attenuated the clone formation and self-renewal ability of tumor cells. The gene set enrichment analysis(GSEA) implied that San C inhibited the tumor cell division cycle by affecting the myelocytomatosis viral oncogene(MYC) signaling pathway. Western blot assay revealed that San C inhibited the expression of cyclin through the regulation of the MYC signaling pathway by lysine demethylase 4B(KDM4B), which ultimately inhibited the growth and proliferation of glioblastoma cells and self-renewal. In conclusion, San C exhibits the potential antitumor activity by targeting the KDM4B-MYC axis to inhibit glioblastoma cell growth, proliferation, and self-renewal.
Humans ; Glioblastoma/genetics* ; Bromodeoxyuridine/therapeutic use* ; Signal Transduction ; Proto-Oncogene Proteins c-myc/metabolism* ; Agar ; Cell Proliferation ; Cell Line, Tumor ; Apoptosis ; Jumonji Domain-Containing Histone Demethylases/metabolism*

Chromodomain-helicase-DNA-binding protein 1 (CHD1) deletion is among the most common mutations in prostate cancer (PCa), but its role remains unclear. In this study, RNA sequencing was conducted in PCa cells after clustered regularly interspaced palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-based CHD1 knockout. Gene set enrichment analysis (GSEA) indicated upregulation of hypoxia-related pathways. A subsequent study confirmed that CHD1 deletion significantly upregulated hypoxia-inducible factor 1α (HIF1α) expression. Mechanistic investigation revealed that CHD1 deletion upregulated HIF1α by transcriptionally downregulating prolyl hydroxylase domain protein 2 (PHD2), a prolyl hydroxylase catalyzing the hydroxylation of HIF1α and thus promoting its degradation by the E3 ligase von Hippel-Lindau tumor suppressor (VHL). Functional analysis showed that CHD1 deletion promoted angiogenesis and glycolysis, possibly through HIF1α target genes. Taken together, these findings indicate that CHD1 deletion enhances HIF1α expression through PHD2 downregulation and therefore promotes angiogenesis and metabolic reprogramming in PCa.
Male ; Humans ; Von Hippel-Lindau Tumor Suppressor Protein/metabolism* ; DNA-Binding Proteins/metabolism* ; Prolyl Hydroxylases/metabolism* ; Hypoxia ; Prostatic Neoplasms/pathology* ; Glycolysis ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Cell Line, Tumor ; DNA Helicases/metabolism*

OBJECTIVE: To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells. METHODS: Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting. RESULTS: The IC₅₀ of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05). CONCLUSIONS Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.
Humans ; Prolyl Hydroxylases ; Carcinoma, Hepatocellular ; Caspase 3 ; bcl-2-Associated X Protein ; Liver Neoplasms ; Signal Transduction ; Apoptosis ; Adenosine Triphosphate

Aging of craniofacial skeleton significantly impairs the repair and regeneration of trauma-induced bony defects, and complicates dental treatment outcomes. Age-related alveolar bone loss could be attributed to decreased progenitor pool through senescence, imbalance in bone metabolism and bone-fat ratio. Mesenchymal stem cells isolated from oral bones (OMSCs) have distinct lineage propensities and characteristics compared to MSCs from long bones, and are more suited for craniofacial regeneration. However, the effect of epigenetic modifications regulating OMSC differentiation and senescence in aging has not yet been investigated. In this study, we found that the histone demethylase KDM4B plays an essential role in regulating the osteogenesis of OMSCs and oral bone aging. Loss of KDM4B in OMSCs leads to inhibition of osteogenesis. Moreover, KDM4B loss promoted adipogenesis and OMSC senescence which further impairs bone-fat balance in the mandible. Together, our data suggest that KDM4B may underpin the molecular mechanisms of OMSC fate determination and alveolar bone homeostasis in skeletal aging, and present as a promising therapeutic target for addressing craniofacial skeletal defects associated with age-related deteriorations.
Aging ; Cell Differentiation ; Facial Bones/physiology* ; Humans ; Jumonji Domain-Containing Histone Demethylases/genetics* ; Mesenchymal Stem Cells/cytology* ; Osteogenesis ; Osteoporosis

Objective: This study aimed to investigate the clinical and prognostic significance of TET2 single nucleotide polymorphism I1762V in patients with acute myeloid leukemia (AML) . Methods: The high-throughput sequencing method was used to sequence 58 hematological tumor-related genes in bone marrow samples from 413 patients with AML. TET2 I1762V and other somatic mutations were annotated and compared with patients' clinical information and prognosis. Results: I1762V was found in 154 patients with AML, which was significantly different from the general population in NyuWa Chinese Population Variant Database (χ(2)=72.4, P<0.001) . I1762V was not related to sex, age, and karyotype of patients with AML (P>0.05) . Patients with I1762V had a significantly higher proportion of NPM1 and KIT gene mutations than others (P<0.001) . NPM1 and KIT mutations were mutually exclusive. The survival analysis results revealed that the overall survival (OS) and progression-free survival (PFS) of patients with AML with I1762V were significantly greater than those of wild-type patients (HR=0.57, P=0.030; HR=0.55, P=0.020) , whereas the OS and PFS in patients with AML with DNMT3A mutation (with or without I1762V mutation) were lower than those of wild-type patients (HR=1.79, P=0.030; HR=1.74, P=0.040) . Conclusion: TET2 SNP I1762V has been linked to AML. I1762V is a prognostic factor of patients with AML, which can be used to guide the treatment and evaluate the prognosis of AML.
DNA-Binding Proteins/genetics* ; Dioxygenases/genetics* ; Humans ; Leukemia, Myeloid, Acute/genetics* ; Mutation ; Nuclear Proteins/genetics* ; Polymorphism, Single Nucleotide ; Prognosis

Osteoarthritis (OA) is a prevalent joint disease with no effective treatment strategies. Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis. Although multiple studies have detected potential regulatory mechanisms underlying OA and have concentrated on developing novel treatment strategies, the epigenetic control of OA remains unclear. Histone demethylase JMJD3 has been reported to mediate multiple physiological and pathological processes, including cell differentiation, proliferation, autophagy, and apoptosis. However, the regulation of JMJD3 in aberrant force-related OA and its mediatory effect on disease progression are still unknown. In this work, we confirmed the upregulation of JMJD3 in aberrant force-induced cartilage injury in vitro and in vivo. Functionally, inhibition of JMJD3 by its inhibitor, GSK-J4, or downregulation of JMJD3 by adenovirus infection of sh-JMJD3 could alleviate the aberrant force-induced chondrocyte injury. Mechanistic investigation illustrated that aberrant force induces JMJD3 expression and then demethylates H3K27me3 at the NR4A1 promoter to promote its expression. Further experiments indicated that NR4A1 can regulate chondrocyte apoptosis, cartilage degeneration, extracellular matrix degradation, and inflammatory responses. In vivo, anterior cruciate ligament transection (ACLT) was performed to construct an OA model, and the therapeutic effect of GSK-J4 was validated. More importantly, we adopted a peptide-siRNA nanoplatform to deliver si-JMJD3 into articular cartilage, and the severity of joint degeneration was remarkably mitigated. Taken together, our findings demonstrated that JMJD3 is flow-responsive and epigenetically regulates OA progression. Our work provides evidences for JMJD3 inhibition as an innovative epigenetic therapy approach for joint diseases by utilizing p5RHH-siRNA nanocomplexes.
Cartilage, Articular/pathology* ; Chondrocytes/metabolism* ; Down-Regulation ; Epigenesis, Genetic ; Humans ; Jumonji Domain-Containing Histone Demethylases/metabolism* ; Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism* ; Osteoarthritis/pathology* ; RNA, Small Interfering/pharmacology*

OBJECTIVE: To observe the effect of Biantie (bian stone plaste) pretreatment on serum level of prolyl hydroxylase domain 2 (PHD2) and hypoxia-inducible factor-1α (HIF-1α) in rats with acute hypobaric hypoxia induced-brain injury, and to explore the possible mechanism of Biantie on preventing brain injury at high altitude. METHODS: Forty-five male SD rats were randomly divided into a blank group, a model group, a Biantie group, a medication group and a Biantie+inhibitor group, 9 rats in each group. The rats in the Biantie group the and the Biantie+inhibitor group were pretreated with Biantie at "Taiyuan" (LU 9), "Neiguan" (PC 6) and "Renying" (ST 9), 2 h each time, once a day; the rats in the medication group were treated with intragastric administration of rhodiola capsule solution (280 mg/kg) for 14 d; the rats in the Biantie+inhibitor group were intraperitoneally injected with the PHD inhibitor dimethyloxalyl glycine (DMOG) at a dose of 40 mg/kg 24 h before the establishment of the model. After the intervention, except for the blank group, the rats in the remaining 4 groups were placed in the oxygen chamber to simulate a high-altitude environment to establish the acute hypobaric hypoxia brain injury model. The arterial blood-gas analysis indexes [blood oxygen saturation (SaO₂), lactic acid (Lac), blood sodium (Na⁺), blood potassium (K⁺)] and brain water content were detected in each group; the histomorphology of cerebral cortex was observed by HE staining; the serum levels of PHD2 and HIF-1α as well as vascular endothelial growth factor (VEGF) were detected by ELISA; the VEGF protein expression in brain tissue was detected by Western blot; the VEGF mRNA expression in brain tissue was detected by real-time fluorescent quantitative PCR. RESULTS: Compared with the blank group, the levels of SaO₂ and Na⁺ in the model group were decreased (P<0.05), while the levels of Lac and K⁺ as well as the water content of brain tissue were increased (P<0.05). Compared with the model group, the level of SaO₂ in the Biantie group and the medication group was increased (P<0.05), while the levels of Lac, K⁺ and the water content of brain tissue were decreased (P<0.05); the level of Na⁺ in the Biantie group was increased (P<0.05). Compared with the Biantie group, the level of SaO₂ in the Biantie+inhibitor group was decreased (P<0.05), and the level of Lac and the water content of brain tissue were increased (P<0.05). In the model group, the cortical tissue cells were loose and disordered, the cortical blood vessels were dilated, and the cells were obviously swollen; the anoxic injury in the Biantie group and the medication group was lighter, and the anoxic injury in the Biantie+inhibitor group was more obvious than that in the Biantie group. Compared with the blank group, the serum PHD2 content in the model group was decreased and the HIF-1α content was increased (P<0.05), and the content of VEGF in serum and VEGF protein and mRNA expressions in brain were increased (P<0.05). Compared with the model group, the content of PHD2 in serum in the Biantie group and the medication group was increased (P<0.05), and the level of HIF-1α was decreased (P<0.05), and the content of VEGF in serum as well as VEGF protein and mRNA expressions in brain were decreased (P<0.05). Compared with the Biantie group, the serum PHD2 content in the Biantie+inhibitor group was decreased and HIF-1α level were increased (P<0.05), and the content of VEGF in serum as well as VEGF mRNA expression in brain were increased (P<0.05). CONCLUSION Biantie at "Taiyuan" (LU 9), "Neiguan" (PC 6) and "Renying" (ST 9) could regulate serum PHD2/HIF-1α to down-regulate VEGF expression, reduce brain edema and enhance anti-hypoxia ability, so as to achieve the purpose of preventing brain injury at high altitude.
Animals ; Rats ; Male ; Prolyl Hydroxylases/metabolism* ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Rats, Sprague-Dawley ; Procollagen-Proline Dioxygenase/metabolism* ; Brain Injuries ; Brain/metabolism* ; RNA, Messenger ; Water

OBJECTIVE: To investigate the role of proline 4-hydroxylase Ⅱ (P4HA2) in the occurrence and progression of liver cancer. METHODS: GEPIA and Human Protein Atlas database were used to predict the expression of P4HA2 in hepatocellular carcinoma (HCC), and K-M plotter online database was used to analyze the relationship between P4HA2 expression and the prognosis of HCC. We also examined the expressions of P4HA2 in HCC cells and normal hepatocytes using qRT-PCR and Western blotting. With lentivirus-mediated RNA interference, P4HA2 expression was knocked down in hepatoma SNU-449 and Hep-3B cells, and the changes in cell proliferation, migration and invasion were assessed using cell counting kit-8 (CCK-8) assay, colony formation test, scratch test and Transwell assay. The changes in the expressions of epithelial-mesenchymal transition (EMT) and PI3K/Akt/mTOR signal pathway-related proteins were detected using Western blotting. RESULTS: Online database analysis showed that the expression of P4HA2 was significantly higher in HCC tissues than in normal liver tissues (P < 0.05). The expression levels of P4HA2 mRNA and protein were also significantly higher in HCC cell lines than in normal hepatocytes (P < 0.01). Lentivirus-mediated RNA interference of P4HA2 significantly lowered the expression levels of P4HA2 mRNA and protein in the hepatoma cells (P < 0.05) and caused obvious inhibition of cell proliferation, migration and invasion. P4HA2 knockdown significantly increased the expression of E-cadherin protein, lowered the expressions of N-cadherin and Snail, and obviously decreased the expressions of phosphorylated PI3K, AKT and mTOR (P < 0.05). CONCLUSION P4HA2 enhances the proliferation, migration, invasion, and EMT of hepatoma cells by activating the PI3K/Akt/mTOR signaling pathway to promote the occurrence and progression of liver cancer.
Carcinoma, Hepatocellular/pathology* ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Humans ; Liver Neoplasms/pathology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Prolyl Hydroxylases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; RNA, Messenger ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism*

Hypoxia-inducible factors (HIFs) are one of the primary transcription factors regulating oxygen balance, and their stability is determined by the hydroxylation state of the prolyl hydroxylase domain (PHD) that is sensitive to oxygen. In recent years, studies have shown that HIFs-prolyl hydroxylases (PHDs) oxygen-sensing pathway is involved in the process of cellular ferroptosis. Ferroptosis, a new type of cell death, different from necrosis, apoptosis, necrotizing apoptosis, and pyroptosis, is essentially a programmed death caused by the accumulation of iron-dependent lipid peroxides in cells. This paper focuses on the role and mechanism of the HIFs-PHDs oxygen-sensing pathway in cellular ferroptosis involved in nerve diseases, tumors, lung injury, and chemical nerve damage from three aspects of iron metabolism, lipid metabolism, and glutathione (GSH) synthesis/metabolism. This review will provide a theoretical basis and new ideas for the development of novel drugs targeting the HIFs-PHDs oxygen-sensing pathway and capable of regulating ferroptosis for the treatment of diseases related to ferroptosis such as nervous system diseases and tumors.
Apoptosis ; Basic Helix-Loop-Helix Transcription Factors ; Ferroptosis ; Oxygen ; Prolyl Hydroxylases