Hypoxia-inducible factor (HIF-1α), a core transcription factor responding to changes in cellular oxygen levels, is closely associated with a wide range of physiological and pathological conditions. However, its differential impacts on vascular cell types and molecular programs modulating human vascular homeostasis and regeneration remain largely elusive. Here, we applied CRISPR/Cas9-mediated gene editing of human embryonic stem cells and directed differentiation to generate HIF-1α-deficient human vascular cells including vascular endothelial cells, vascular smooth muscle cells, and mesenchymal stem cells (MSCs), as a platform for discovering cell type-specific hypoxia-induced response mechanisms. Through comparative molecular profiling across cell types under normoxic and hypoxic conditions, we provide insight into the indispensable role of HIF-1α in the promotion of ischemic vascular regeneration. We found human MSCs to be the vascular cell type most susceptible to HIF-1α deficiency, and that transcriptional inactivation of ANKZF1, an effector of HIF-1α, impaired pro-angiogenic processes. Altogether, our findings deepen the understanding of HIF-1α in human angiogenesis and support further explorations of novel therapeutic strategies of vascular regeneration against ischemic damage.
Humans ; Vascular Endothelial Growth Factor A/metabolism* ; Endothelial Cells/metabolism* ; Transcription Factors/metabolism* ; Gene Expression Regulation ; Hypoxia/metabolism* ; Cell Hypoxia/physiology*

Ischemic stroke is a major public health problem worldwide. Although the circadian clock is involved in the process of ischemic stroke, the exact mechanism of the circadian clock in regulating angiogenesis after cerebral infarction remains unclear. In the present study, we determined that environmental circadian disruption (ECD) increased the stroke severity and impaired angiogenesis in the rat middle cerebral artery occlusion model, by measuring the infarct volume, neurological tests, and angiogenesis-related protein. We further report that Bmal1 plays an irreplaceable role in angiogenesis. Overexpression of Bmal1 promoted tube-forming, migration, and wound healing, and upregulated the vascular endothelial growth factor (VEGF) and Notch pathway protein levels. This promoting effect was reversed by the Notch pathway inhibitor DAPT, according to the results of angiogenesis capacity and VEGF pathway protein level. In conclusion, our study reveals the intervention of ECD in angiogenesis in ischemic stroke and further identifies the exact mechanism by which Bmal1 regulates angiogenesis through the VEGF-Notch1 pathway.
Rats ; Animals ; Vascular Endothelial Growth Factor A/pharmacology* ; Brain Ischemia/metabolism* ; Ischemic Stroke ; Signal Transduction ; ARNTL Transcription Factors/pharmacology* ; Neovascularization, Physiologic/physiology*

OBJECTIVES: Fluorouracil chemotherapeutic drugs are the classic treatment drugs of gastric cancer. But the problem of drug resistance severely limits their clinical application. This study aims to investigate whether hypoxia microenvironment affects gastric cancer resistance to 5-fluorouracil (5-FU) and discuss the changes of gene and proteins directly related to drug resistance under hypoxia condition. METHODS: Gastric cancer cells were treated with 5-FU in hypoxia/normoxic environment, and were divided into a Normoxic+5-FU group and a Hypoxia+5-FU group. The apoptosis assay was conducted by flow cytometry Annexin V/PI double staining. The real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression level of hypoxia inducible factor-1α (HIF-1α), multidrug resistance (MDR1) gene, P-glycoprotein (P-gp), and vascular endothelial growth factor (VEGF) which were related to 5-FU drug-resistance. We analyzed the effect of hypoxia on the treatment of gastric cancer with 5-FU. RESULTS: Compared with the Normoxic+5-FU group, the apoptosis of gastric cancer cells treated with 5-FU in the Hypoxia+5-FU group was significantly reduced (P<0.05), and the expression of apoptosis promoter protein caspase 8 was also decreased. Compared with the the Normoxic+5-FU group, HIF-1α mRNA expression in the Hypoxia+5-FU group was significantly increased (P<0.05), and the mRNA and protein expression levels of MDR1, P-gp and VEGF were also significantly increased (all P<0.05). The increased expression of MDR1, P-gp and VEGF had the same trend with the expression of HIF-1α. CONCLUSIONS Hypoxia is a direct influencing factor in gastric cancer resistance to 5-FU chemotherapy. Improvement of the local hypoxia microenvironment of gastric cancer may be a new idea for overcoming the resistance to 5-FU in gastric cancer.
Humans ; Fluorouracil/therapeutic use* ; Vascular Endothelial Growth Factor A/metabolism* ; Stomach Neoplasms/drug therapy* ; Drug Resistance, Multiple ; Vascular Endothelial Growth Factors/metabolism* ; Hypoxia ; ATP Binding Cassette Transporter, Subfamily B/genetics* ; ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics* ; Cell Line, Tumor ; Cell Hypoxia ; RNA, Messenger/metabolism* ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; Tumor Microenvironment

PURPOSE: Wound represents a major health challenge as they consume a large amount of healthcare resources to improve patient's quality of life. Many scientific studies have been conducted in search of ideal biomaterials with wound-healing activity for clinical use and collagen has been proven to be a suitable candidate biomaterial. This study intended to investigate the wound healing activity of collagen peptides derived from jellyfish following oral administration. METHODS: In this study, collagen was extracted from the jellyfish--Rhopilema esculentum using 1% pepsin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fourier transform infrared (FTIR) were used to identify and determine the molecular weight of the jellyfish collagen. Collagenase II, papain and alkaline proteinase were used to breakdown jellyfish collagen into collagen peptides. Wound scratch assay (in vitro) was done to determine migration potential of human umbilical vein endothelial cells (HUVEC) covering the artificial wound created on the cell monolayer following treatment with collagen peptides. In vivo studies were conducted to determine the effects of collagen peptides on wound healing by examining wound contraction, re-epithelialization, tissue regeneration and collagen deposition on the wounded skin of mice. Confidence level (p < 0.05) was considered significant using GraphPad Prism software. RESULTS: The yield of collagen was 4.31%. The SDS-PAGE and FTIR showed that extracted collagen from jellyfish was type I. Enzymatic hydrolysis of this collagen using collagenase II produced collagen peptides (CP) and hydrolysis with alkaline proteinase/papain resulted into collagen peptides (CP). Tricine SDS-PAGE revealed that collagen peptides consisted of protein fragments with molecular weight <25 kDa. Wound scratch assay showed that there were significant effects on the scratch closure on cells treated with collagen peptides at a concentration of 6.25 μg/mL for 48 h as compared to the vehicle treated cells. Overall treatment with collagen peptide on mice with full thickness excised wounds had a positive result in wound contraction as compared with the control. Histological assessment of peptides treated mice models showed remarkable sign of re-epithelialization, tissue regeneration and increased collagen deposition. Immunohistochemistry of the skin sections showed a significant increase in β-fibroblast growth factor (β-FGF) and the transforming growth factor-β (TGF-β) expression on collagen peptides treated group. CONCLUSION Collagen peptides derived from the jellyfish-Rhopilema esculentum can accelerate the wound healing process thus could be a therapeutic potential product that may be beneficial in wound clinics in the future.
Administration, Oral ; Animals ; Collagen ; administration & dosage ; isolation & purification ; metabolism ; pharmacology ; Fibroblast Growth Factors ; metabolism ; Human Umbilical Vein Endothelial Cells ; Humans ; Male ; Regeneration ; Scyphozoa ; chemistry ; Skin ; metabolism ; Skin Physiological Phenomena ; Stimulation, Chemical ; Transforming Growth Factor beta1 ; metabolism ; Wound Healing ; drug effects

Angiogenesis is a crucial process in the development of inflammatory diseases, including cancer, psoriasis and rheumatoid arthritis. Recently, several alkaloids from Picrasma quassioides had been screened for angiogenic activity in the zebrafish model, and the results indicated that 1-methoxycarbony-β-carboline (MCC) could effectively inhibit blood vessel formation. In this study, we further confirmed that MCC can inhibit, in a concentration-dependent manner, the viability, migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro, as well as the regenerative vascular outgrowth of zebrafish caudal fin in vivo. In the zebrafish xenograft assay, MCC inhibited the growth of tumor masses and the metastatic transplanted DU145 tumor cells. The proteome profile array of the MCC-treated HUVECs showed that MCC could down-regulate several angiogenesis-related self-secreted proteins, including ANG, EGF, bFGF, GRO, IGF-1, PLG and MMP-1. In addition, the expression of two key membrane receptor proteins in angiogenesis, TIE-2 and uPAR, were also down-regulated after MCC treatment. Taken together, these results shed light on the potential therapeutic application of MCC as a potent natural angiogenesis inhibitor via multiple molecular targets.
Angiogenesis Inhibitors ; chemistry ; pharmacology ; Animals ; Carbolines ; chemistry ; pharmacology ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Epidermal Growth Factor ; genetics ; metabolism ; Fibroblast Growth Factors ; genetics ; metabolism ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; metabolism ; Humans ; Insulin-Like Growth Factor I ; genetics ; metabolism ; Neovascularization, Physiologic ; drug effects ; Picrasma ; chemistry ; Plant Extracts ; chemistry ; pharmacology ; Receptor, TIE-2 ; genetics ; metabolism ; Zebrafish ; embryology

PURPOSE: The aim of this study was to determine the relationship of hypoxia-inducible factor-2 (HIF-2α) and vascular endothelial growth factor (VEGF) with radiographic severity in primary osteoarthritis (OA) of the knee. Expression of these two factors in cartilage samples from OA knee joints was examined at mRNA and protein levels. MATERIALS AND METHODS: Knee joints were examined using plain radiographs, and OA severity was assessed using the Kellgren and Lawrence (KL) grading system. Specimens were collected from 29 patients (31 knees) who underwent total knee replacement because of severe medial OA of the knee (KL grades 3 and 4), 16 patients who underwent knee arthroscopy (KL grade 2), and 5 patients with traumatic knees (KL grade 0). HIF-2α and VEGF expression was quantified by real-time polymerase chain reaction and western blotting. RESULTS: Cartilage degeneration correlated with the radiographic severity grade. OA severity, determined using the Mankin scale, correlated positively with the KL grade (r=0.8790, p<0.01), and HIF-2α and VEGF levels with the radiographic severity of knee OA (r=0.7001, p<0.05; r=0.6647, p<0.05). CONCLUSION: In OA cartilage, HIF-2α and VEGF mRNA and protein levels were significantly and positively correlated. The expression of both factors correlated positively with the KL grade. HIF-2α and VEGF, therefore, may serve as biochemical markers as well as potential therapeutic targets in knee OA.
Adult ; Aged ; Arthroplasty, Replacement, Knee ; Arthroscopy ; Basic Helix-Loop-Helix Transcription Factors/*metabolism ; Biomarkers/*blood ; Cartilage/*metabolism ; Female ; Humans ; Knee Joint/*diagnostic imaging ; Male ; Middle Aged ; Osteoarthritis, Knee/*blood/diagnostic imaging/physiopathology ; RNA, Messenger ; Radiography ; Real-Time Polymerase Chain Reaction ; Severity of Illness Index ; Vascular Endothelial Growth Factor A/*metabolism

OBJECTIVETo explore the formation of pre-metastatic niche in the mouse lung and to study the underlying molecular mechanisms whereby primary breast carcinoma-derived factors mediate recruitment of bone marrow-derived cells (BMDCs) and affect the formation of pre-metastatic lung environment before the arrival of tumor cells.

METHODSMammary carcinoma 4T1 cells were inoculated into the mammary gland to construct mouse model of breast cancer. Confocal microscopy was used to detect the recruitment of BMDCs in the pre-metastatic lungs. The expression of factors in the mouse sera and 4T1 cell culture media was assayed using RayBio Custom mouse cytokine antibody array kit. The mice were injected daily with recombinant VEGF for 7 consecutive days to observe the effect of VEGF on BMDCs recruitment in the mouse lung.

RESULTSNo BMDCs were observed in the lungs of control and 4T1-tumor-bearing mice on day 0. On day 7 and 14, clusters of BMDCs observed in the lungs of 4T1-tumor-bearing mice were 8.7±2.2/objective field and 48.8±3.2/objective field, respectively, significantly higher than those in the control mice (1.1±0.8/objective field and 3.1±1.7/objective field) (P<0.05 for both). Confocal microscopic observation found that metastatic breast cancer cells preferentially facilitate BMDCs recruitment sites in the pre-metastatic mouse lungs. The levels of VEGF, GM-CSF, and IL-6 in the serum of 4T1-tumor-bearing mice were significantly increased compared with those in the control group (P<0.05 for all). However, VEGF was detected only in the culture media of 4T1 cells. The amount of BMDCs in the mouse lung tissue was (22.8±3.6)/objective field in the VEGF group and (3.1±0.4)/objective field in the control group (P<0.05). There were 36.8±5.4 metastatic foci in the lung tissue of VEGF group and 12.6±2.2 in the control group (P<0.05).

CONCLUSIONSThe results of this study demonstrate that primary breast cancer cells can alter the lung microenvironment during the pre-metastatic phase and induce the formation of pre-metastatic niche. Primary tumor cell-derived VEGF may be a crucial factor responsible for the formation of pre-metastatic niche.

Animals ; Bone Marrow Cells ; Breast Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; blood ; Humans ; Interleukin-6 ; blood ; Lung ; pathology ; Lung Neoplasms ; secondary ; Mice ; Recombinant Proteins ; administration & dosage ; Time Factors ; Tumor Microenvironment ; Vascular Endothelial Growth Factor A ; administration & dosage ; physiology ; secretion

Cell Hypoxia ; physiology ; Cells, Cultured ; Diabetic Retinopathy ; metabolism ; Female ; Humans ; Intercellular Adhesion Molecule-1 ; metabolism ; Male ; Middle Aged ; Monocytes ; metabolism ; Prospective Studies ; Vascular Endothelial Growth Factors ; metabolism

OBJECTIVETo investigate the effect of extracellular signal-regulated kinase (ERK) signaling pathway on the endothelial differentiation of periodontal ligament stem cells (PDLSC).

METHODSHuman PDLSC was cultured in the medium with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF) to induce endothelial differentiation. Endothelial inducing cells was incubated with U0126, a specific p-ERK1/2 inhibitor. PDLSC from one person were randomly divided into four groups: control group, endothelial induced group, endothelial induced+DMSO group and endothelial induced+U0126 group. The protein expression of the p-EKR1/2 was analyzed by Western blotting at 0, 1, 3, 6 and 12 hours during endonthelial induction. The mRNA expressions of CD31, VE-cadherin, and VEGF were detected by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) after a 7-day induction. The proportion of CD31(+) to VE-cadherin(+) cells was identified by flow cytometry, and the ability of capillary-like tubes formation was detected by Matrigel assay after a 14-day induction. The measurement data were statistically analyzed.

RESULTSPhosphorylated ERK1/2 protein level in PDLSC was increased to 1.24±0.12 and 1.03±0.24 at 1 h and 3 h respectively, during the endothelial induction (P<0.01). The mRNA expressions of CD31 and VEGF in induced+U0126 group were decreased to 0.09±0.18 and 0.49±0.17, which were both significantly different with those in induced group (P<0.05). The proportion of CD31(+) to VE-cadherin(+) cells of induced+U0126 group were decreased to 5.22±0.85 and 3.56±0.87, which were both significantly different with those in induced group (P<0.05). In Matrigel assay, the branching points, tube number and tube length were decreased to 7.0±2.7, 33.5±6.4, and (15 951.0±758.1) pixels, which were all significantly different with those in induced group (P<0.05).

CONCLUSIONSThe endothelial differentiation of PDLSC is positively regulated by ERK signaling pathway. Inhibition of ERK1/2 phosphorylation could suppress endothelial differentiation of PDLSC.

Antigens, CD ; genetics ; metabolism ; Butadienes ; pharmacology ; Cadherins ; genetics ; metabolism ; Cell Differentiation ; Endothelial Cells ; cytology ; physiology ; Enzyme Inhibitors ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; physiology ; Fibroblast Growth Factor 2 ; pharmacology ; Humans ; Mitogen-Activated Protein Kinase 3 ; antagonists & inhibitors ; metabolism ; Nitriles ; pharmacology ; Periodontal Ligament ; cytology ; metabolism ; Phosphorylation ; Platelet Endothelial Cell Adhesion Molecule-1 ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Random Allocation ; Signal Transduction ; Stem Cells ; cytology ; physiology ; Time Factors ; Vascular Endothelial Growth Factor A ; genetics ; metabolism ; pharmacology

BACKGROUNDAngiogenesis is the formation of new blood vessels to supply nutrients to tumors. Vascular endothelial growth factor (VEGF) and cluster of differentiation 34 (CD34) are important signaling proteins involved in angiogenesis. Many studies have demonstrated that VEGF and CD34 are related to tumor progression. This study focused on the relationship between VEGF, CD34, and perioperative hemorrhage in patients with gastric cancer.

METHODSTo observe the relationship between VEGF and CD34, we tracked 112 patients with advanced gastric cancer for 5 years to assess factors related to hemorrhage, using immunohistochemistry. The results were subjected to statistical analysis using a 2 × 2 contingency table, logistic regression, and receiver operating characteristic (ROC) test.

RESULTSThe concentrations of VEGF and CD34 were critically correlated with perioperative hemorrhage and neural invasion in patients with gastric cancer (P < 0.05). Expression of VEGF and CD34 was related (P < 0.05, χ2 = 6.834). VEGF and CD34 co-expression strongly increased the risk of preoperative bleeding (area under the ROC curve >0.7, P < 0.05).

CONCLUSIONSExpression of VEGF and CD34 was critically correlated with perioperative hemorrhage in gastric cancer patients. Co-expression of VEGF and CD34 could be an effective indicator for evaluating the risk of perioperative bleeding in gastric cancer patients.

Adult ; Aged ; Aged, 80 and over ; Antigens, CD34 ; metabolism ; Female ; Gastrointestinal Hemorrhage ; etiology ; metabolism ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Neovascularization, Pathologic ; complications ; metabolism ; Prognosis ; Retrospective Studies ; Risk Factors ; Stomach Neoplasms ; metabolism ; pathology ; surgery ; Vascular Endothelial Growth Factor A ; metabolism ; Young Adult