Vascular Endothelial Growth Factor Synthesis Research Articles

CDK5RAP3 Inhibition by Hypoxia Activates P38MAPK to Facilitate Angiogenesis.

CDK5RAP3 is a recognized tumor suppressor that inhibits Chk1 and Chk2 and activates p53, all of which are involved with mediating toxin-induced apoptosis of cancer cells. CDK5RAP3 also inhibits p38MAPK phosphorylation and activity via mediating a p38 interaction with wild-type p53-induced phosphatase 1. This study aimed to investigate the antiangiogenic activity of CDK5RAP3 and its molecular mechanisms in human umbilical vein endothelial cells (HUVECs) under conditions of hypoxic conditions. Angiogenesis was induced in HUVECs mainly by vascular endothelial growth factor (VEGF). The CDK5RAP3 levels of HUVECs were reduced in a time-dependent manner in response to hypoxic treatment at 2% O2. The reduction of CDK5RAP3 was accompanied with increased p38MAPK phosphorylation and activation. Moderate hypoxia was found to significantly increase secreted VEGF concentrations, and the hypoxic conditioned medium (HCM) markedly enhanced proliferation, migration, and tube formation. Our findings indicate that moderate hypoxia facilitates angiogenesis by inhibiting CDK5RAP3. CDK5RAP3 exhibits a clear regulatory role in vascular regeneration, as downregulating its expression in endothelial cells enhances VEGF synthesis and subsequently improves cell migration and lumen formation capability. This study presents evidence indicating that moderate hypoxia facilitates angiogenesis by inhibiting CDK5RAP3, demonstrating the potential for CKD5RAP3 to be a potent antiangiogenic agent in angiogenesis regulation of cancer, ischemic diseases, and wound healing.

DYNAMICS OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN HEMORRHAGIC STROKE DEPENDING ON THE DISEASE SEVERITY

Introduction. The results of experimental studies indicate the growth factors, in particular the vascular endothelial growth factor, around the hematoma already at the beginning of hemorrhagic stroke.
 The aim of the study: to find out the features of vascular endothelial growth factor expression in patients with hemorrhagic stroke depending on the disease severity.
 Research metods. 53 patients with hemorrhagic stroke were examined. The control group - 25 people with hypertension without dyscirculatory disorders of cerebral circulation.
 The level of neurological deficit was assessed using the National Institute of Health Stroke Scale (NIHSS).
 Vascular endothelial growth factor (VEGF) in the blood was determined on the 1st, 5th and 21st days of the acute stroke period by enzyme-linked immunosorbent assay (ELISA) (test kits of the company "Biosourse" (USA)). The research results were analyzed by the method of variational statistics using the program "STATISTICA 6.0" (StatSoft, USA).
 Results and discussion. With a mild degree of severity, the content of VEGF in the blood is significantly lower on the 1st and 5th days of the acute period compared to the control group. This may be one of the factors contributing to the development of a hemorrhagic stroke. An increase in VEGF in the first days of the disease can be a marker of the serious condition of patients with hemorrhagic stroke. VEGF levels on the 5th and 21st days are highest in mild cases, and lowest in severe cases. The increased synthesis of VEGF in case of a mild stroke indicates a more adequate response of the endothelium to damage.
 Conclusions. A marker of a mild hemorrhagic stroke can be low VEGF levels in the first days of the disease and their significant increase at the end of the previous period. High VEGF in the blood at the beginning of the disease, and relatively lower indicators (compared to a mild course) at the end of the previous period are associated with the severe condition of patients with hemorrhagic stroke.

Stability and Safety Analysis of Statin-Loaded Nano-films for the Treatment of Diabetic Wound

Diabetes mellitus (DM) is a metabolic disease that delays the regular stages of the wound's healing process due to delayed inflammatory stages. Due to foot pressure points, chronic foot wounds are ultimately considered the primary cause of lower leg amputation. Diabetic patients have vascular dysfunction and neuropathy, leading to inadequate oxygen supply to the wound area. Statins have a crucial role in the regulation of angiogenesis that could increase vascular endothelial growth factor (VEGF) synthesis. By offering a localized treatment approach while minimizing systemic side effects associated with oral medication, this study aimed to develop statin-loaded nanofilms to determine their stability and safety among healthy individuals as a potential procedure for diabetic wound healing. Simvastatin (SIM) loaded nanofilms formulations (F1-F10) were prepared using the solvent casting method. The formulation was optimized based on tests such as physical appearance, tensile strength, microscopic photographs, morphology, and drug content uniformity. ICH guidelines were followed to determine various parameters (physical appearances, tensile strength, microscopic photographs, morphology, and drug content uniformity) for six-month stability study at three different storage conditions. Safety analysis of the nanofilms was performed on healthy human skin using the Draize skin irritation test. Results showed F7 formulation was considered an optimized formulation as well as stable through the storage period at 4 ± 2°C, 25 ± 2°C, and 40 ± 2 °C. Furthermore, Primary Irritation Index results (PII was 0 showed no irritation in case and control groups) indicate its safety and biocompatibility to skin. Thus, the optimized statin-loaded nanofilm is stable, safe, and non-toxic, which may be used as a potential diabetic wound healing agent.

(011) Using Pre-Operative Low Intensity Vestibular Shockwave Therapy Reduces Opioid Use Post-Vestibulectomy

Abstract Introduction Surgeons performing complete vestibulectomy for neuro-proliferative vestibulodynia need to consider two competing post-operative interests: accomplishing acute pain relief in the early postoperative period; reducing risks of persistent post-operative opioid use. Data support that measures to decrease overall post-operative opioid use will decrease future opioid-related adverse events including opioid abuse and addiction. Sexual medicine providers are thus motivated to identify strategies such as pre-operative low intensity shockwave therapy (LISWT) to decrease opioid use in these vestibulectomy patients. To date, only one study has been published assessing the effect of pre-operative LISWT on surgical outcome. Dumfarth at al reported in a prospective randomized study that pre-operative LISWT significantly improved lower extremity wound healing compared to controls in patients undergoing vein harvesting for coronary artery bypass graft surgery. While Dumfarth et al did not directly assess post-operative pain, pre-operative LISWT was associated with statistically significantly increased satisfactory healing, reduced disturbance of healing and reduced minor skin infections, all consistent with less post-operative pain. It was hypothesized that pre-operative LISWT improved wound healing via enhanced blood supply and angiogenesis through expression of vascular endothelial growth factor (VEGF) and nitric oxide synthesis, and via anti-inflammatory action downregulating necrosis factor B activation thereby lowering inflammatory cytokines. Objectives We wished to see if pre-operative LISWT would reduce opioid use in women undergoing complete vestibulectomy. The objective of this study was to compare the use of opioids following vestibulectomy when LISWT with Urogold 100™ MTS was applied just prior to surgery versus no shockwave. LISWT is a non-invasive, non-pharmacologic, non-surgical treatment strategy with low morbidity that is FDA-cleared for pain amelioration in the US as non-significant risk in humans, Urogold 100™MTS provides unfocused electrohydraulic shockwaves with a unique parabolic reflector. Methods Patients scheduled for surgery were required to present to the hospital 4 days before surgery for a COVID-19 test. On that day and each subsequent day until surgery, based on the patient’s availability, the patient presented to the office for approximately 2400 shocks to the vestibule. This is a descriptive study of the patients’ post-operative experiences with pain. Results To date 4 women have undergone LISWT just prior to surgery. At the time of surgery Exparel was delivered to the site, allowing them 24-36 hours of anesthesia to the area so they could travel home easily. Patients were prescribed Percocet to be take every 4 hours as needed. Post-op patients routinely use this opioid 4-6 times a day for multiple days, causing constipation among the many side effects. The women who underwent LISWT immediately prior to surgery have experienced decreased levels of pain post-operatively such that they are using ½ tab of Percocet at bedtime or twice a day, thus decreasing opioid use with all of its potential side effects. Conclusions Performing LISWT using Urogold 100™MTS may reduce the need for opioid medications after total vestibulectomy with vaginal advancement flap as it may mediate pain after the surgical procedure. Disclosure No.

Combined Pulsed Magnetic Field and Radiofrequency Electromagnetic Field Enhances MMP-9, Collagen-4, VEGF Synthesis to Improve Wound Healing Via Hif-1α/eNOS Pathway.

The blood supply of the tissue is very important in the acceleration of wound healing. Radiofrequency electromagnetic field (RF) and the pulsed magnetic field (PMF) increase vasodilation to contribute wound healing. The aim of this study was to evaluate the effects of RF and PMF on wound healing via hypoxia-inducible factor-1 alpha (Hif-1α)/endothelial nitric oxide synthase (eNOS) pathway. Forty-eight rats were divided into 4 groups as sham (wound created only), PMF (27.12MHz, 12 times a day at 30-min intervals), RF (0.5 mT, continuously) and PMF + RF groups. Wounds were created at 1.5 × 1.5cm size to the dorsal region, and animals were put into unit. Six animals were killed on days 4 and 7; wound tissues were collected for histopathological, immunohistochemical as collagen-4, cytokeratin, matrix metalloproteinase-9 (MMP-9), vascular endothelial growth factor (VEGF) staining and Hif-1α/eNOS/VEGF expressions. On day 4, in addition to increasing VEGF and MMP-9 stainings, connection between intact tissue and scar tissue which was stronger in the RF- and PMF-applied groups was observed. On day 7, epithelization started; inflammatory reaction decreased; collagen production, cytokeratin, VEGF and MMP-9 expression enhanced, especially in the RF + PMF applied group. eNOS, Hif-1α and VEGF expression levels were found to be significantly highest in both days of RF + PMF-applied group. This study revealed that both in vitro RF and PMF applications can cause notable changes in factors that are required for tissue repair on wound healing such as epithelization, connective tissue formation, collagen production and angiogenesis via vasodilatory Hif-1α/eNOS pathway and VEGF signaling. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Leptin-VEGF crosstalk in excess body mass and related disorders: A systematic review.

By 2030, it is expected that a billion people will have suffer from obesity. Adipose tissue synthesizes leptin, an adipokine that affects cardiovascular risk. Leptin intensifies the synthesis of vascular endothelial growth factor (VEGF). Our study reviews recent reports on leptin-VEGF crosstalk in obesity and related disorders. PubMed, Web of Science, Scopus, and Google Scholar were searched. One hundred and one articles involving human, animal, and in vitro research were included. In vitro studies show the crucial role of interaction between endothelial cells and adipocytes and hypoxia as a factor that intensifies leptin's effects on VEGF. Leptin-VEGF crosstalk promotes the progression of cancer. The animal research reveal that a high-fat diet enhances leptin and VEGF crosstalk. Genetic and epigenetic mechanisms and procreator-offspring programming may be involved in leptin-VEGF crosstalk. Some female-specific characteristics of leptin-VEGF relation in obesity were observed. The human studies have shown that increased leptin and VEGF synthesis and leptin-VEGF crosstalk are factors linking obesity with elevated cardiovascular risk. The studies of the last 10 years documented a range of significant aspects of leptin-VEGF crosstalk specific for obesity and related disorders, shedding new light on the link between obesity and increased cardiovascular risk.

Research Progress of Serum VEGF and FAS in Prognosis of Gastric Cancer

Vascular endothelial growth factor (VEGF) is an important factor to promote endothelial cell division and angiogenesis. In physiological conditions, the expression level of VEGF in human tissues is very low. Ischemia, hypoxia and many tumors can promote the synthesis and secretion of VEGF, and its expression level is related to the degree of vascularization of tumors, the proliferation, growth and metastasis of tumor cells. Fatty acid synthase (FAS) is a key enzyme for endogenous fatty acid synthesis, which is expressed at a low level in normal tissue cells, while FASN in a variety of tumor cells is continuously highly expressed to meet the energy needs of cell proliferation and the excessive demand for rapid proliferation of tumor cells to form cell membrane lipids. A large amount of research shows that VEGF and FAS play an important role in the development and development of many tumors, and the abnormally high expression in tumor tissue cells is positively correlated with serum VEGF and FAS levels, which is closely related to the prognosis of tumors. Gastric cancer (GC) is one of the most common clinical malignant tumors of the digestive tract, and its incidence and mortality have shown an increasing trend in recent years, and the prognosis is poor, seriously endangering human health. The biological properties of GC are related to the level of VEGF and FAS expression in tissues and serum. This article reviews the research progress of VEGF and FAS, their expression in GC and their prognosis.

Vascular response to stress: Protective action of the bisphosphonate alendronate.

Since several additional actions of bone bisphosphonates have been proposed, we studied the effect of the bisphosphonate alendronate (ALN) on the vascular response to environmental stress. Primary cultures of endothelial cells (EC) and vascular smooth muscle cells (VSMC) exposed to strained conditions were employed for experimental evaluation. After ALN treatment, cell migration, proliferation, and angiogenesis assays were performed. The participation of signal transduction pathways in the biochemical action of ALN was also assessed. In VSMC cultures, ALN counteracted the stimulation of cellular migration elicited by the proinflammatory agent lipopolysaccharide (LPS) or by high levels of calcium and phosphorus (osteogenic medium). Indeed, ALN reduced the increase of VSMC proliferation evoked by the stressors. When LPS and osteogenic medium were added simultaneously, the enhancement of cell proliferation dropped to control values in the presence of ALN. The mechanism of action of ALN involved the participation of nitric oxide synthase, mitogen-activated protein kinase (MAPK), and protein kinase C (PKC) signaling pathways. The study revealed that ALN exhibits a proangiogenic action. On EC, ALN enhanced vascular endothelial growth factor (VEGF) synthesis, and induced capillary-like tube formation in a VEGF-dependent manner. The presence of vascular stress conditions (LPS or osteogenic medium) did not modify the proangiogenic action elicited by ALN. The findings presented suggest an extra-bone biological action of ALN, which could contribute to the maintenance of vascular homeostasis avoiding cellular damage elicited by environmental stress.

New [1,2,4]triazolo[4,3-c]quinazoline derivatives as vascular endothelial growth factor receptor-2 inhibitors and apoptosis inducers: Design, synthesis, docking, and antiproliferative evaluation.

In continuation of our previous efforts in the field of design and synthesis ofvascular endothelial growth factor receptor(VEGFR)-2 inhibitors, a new series of [1,2,4]triazolo[4,3-c]quinazoline derivatives were designed and synthesized as modified analogs of some reported VEGFR-2 inhibitors. The synthesized compounds were designed to have the essential pharmacophoric features of VEGFR-2 inhibitors. Antiproliferative activities of the synthesized compounds were investigated against two tumor cell lines (HepG2 and HCT-116) using sorafenib as a positive control. Compound 10k emerged as the most promising antiproliferative agent with IC50 values of 4.88 and 5.21 µM against HepG2 and HCT-116 cells, respectively. Also, it showed the highest inhibitory activity against VEGFR-2 with an IC50 value of 53.81 nM compared to sorafenib (IC50 = 44.34 nM). Cell cycle analysis revealed that compound 10k can arrest HepG2 cells at both the S and G2/M phases. In addition, this compound produced a tenfold increase in apoptotic cells compared to the control. Furthermore, the effect of compound 10k on the expression level of BAX, Bcl-2, and caspase-3 was assessed. This compound caused a 3.35-fold increase in BAX expression levels and a 1.25-fold reduction in Bcl-2 expression levels. The BAX/Bcl-2 ratio was calculated to be 4.57, indicating a promising apoptotic effect. It also showed a significant increase in the level of caspase-3 (4.12-fold) compared to the control cells. In silico docking, absorption, distribution, metabolism, excretion, and toxicity, and toxicity studies were performed for the synthesized compounds to investigate their binding patterns against the proposed biological target (VEGFR-2) and to assess the drug-likeness characters.

Pre-pperative low intensity vestibular shockwave therapy (LiSWT) decreases opioid use post-vestibulectomy: A pilot study

ABSTRACT Introduction Surgeons performing complete vestibulectomy with vaginal advancement flap reconstruction for suspected neuroproliferative vestibulodynia (NPV) take into consideration the need for acute pain relief in the early postoperative period as well as risks for persistent post-operative opioid use. Post-operative acute pain has traditionally been managed with narcotics which are effective but are highly addictive and can cause unwanted side effects including nausea/vomiting, impaired mental function, and severe constipation/obstipation. We serendipitously observed that one patient who tried to avoid surgery by undergoing numerous vestibular low intensity shockwave therapy (LiWST) treatments used very few narcotics post vestibulectomy. LiWST is FDA-cleared for pain amelioration. It has been hypothesized that LiSWT downregulates inflammatory cytokines, promotes enhancement of blood flow and angiogenesis through expression of vascular endothelial growth factor and nitric oxide synthesis. Objective We performed a pilot study using pre-operative LiSWT to determine whether or not it might decrease post-operative opioid use (oxycodone/acetaminophen tablets; 5mg/325mg) for acute pain management in patients undergoing complete vestibulectomy with vaginal advancement flap for suspected NPV. Method We studied the post-op opioid use of women who underwent complete vestibulectomy at our facility during the period January 1, 2019 through June 30, 2021. We assessed opioid use based on the patient's recall of the total oxycodone/acetaminophen tablets required in the first 30 days post-vestibulectomy. When possible, patients confirmed the use by counting tablets left in the pill container. Women scheduled to undergo vestibulectomy for suspected NPV were placed in the LiSWT study group if they agreed to undergo vestibular LiSWT treatment daily for the three business days immediately pre-operatively. Using the Urogold 100™MTS, LiSWT involved delivery of 1800 shocks to the vestibule per session, energy flux density 0.05-0.1 mJ/mm2, 3 Hz, membrane pressure 3. We compared the post-op opioid use by women in the LiSWT study group to the use by women who did not undergo pre-op LiSWT. Results Forty-five women (mean age 28 years; range 17 - 57) underwent complete vestibulectomy for suspected NPV during the 30 month period. Twenty women (mean age 27 +/- 9 years) agreed to undergo pre-op LiSWT and post-op opioid use was obtained in all. Twenty-five women (mean age 29 +/- 11 years) did not undergo pre-op LiSWT and opioid use was obtained in 19/25 (76%). Mean post-operative opioid use was 47 +/- 13 (range 25 - 90) tablets in those vestibulectomy patients who did not undergo pre-op vestibular LiSWT; opioid side effects included constipation, nausea, fainting, drowsiness, fatigue, and blurred vision. Mean post-op opioid use was 22 +/- 10 (range 1 - 26) tablets in the 20 vestibulectomy patients who did undergo pre-op vestibular LISWT sessions; opioid side effects were restricted to constipation, sleepiness, and nausea. Conclusion In this pilot study, pre-operative low intensity shockwave therapy decreased post-operative opioid use after complete vestibulectomy with vaginal advancement flap. While encouraging, more research is needed. Disclosure Work supported by industry: no.

A Pilot Study of Pre-Operative Vestibular Low Intensity Shockwave Therapy to Decrease Opioid Use Post-Vestibulectomy

ABSTRACT Introduction Surgeons performing complete vestibulectomy with vaginal advancement flap reconstruction for suspected neuroproliferative vestibulodynia (NPV) take into consideration the need for acute pain relief in the early postoperative period as well as risks for persistent post-operative opioid use. Post-operative acute pain has traditionally been managed with narcotics which are effective but are highly addictive and can cause unwanted side effects including nausea/vomiting, impaired mental function, and severe constipation/obstipation. We serendipitously observed that one patient who tried to avoid surgery by undergoing numerous vestibular low intensity shockwave therapy (LiWST) treatments used very few narcotics post vestibulectomy. LiWST is FDA-cleared for pain amelioration. It has been hypothesized that LiSWT downregulates inflammatory cytokines, promotes enhancement of blood flow and angiogenesis through expression of vascular endothelial growth factor and nitric oxide synthesis. Objective We performed a pilot study using pre-operative LiSWT to determine whether or not it might decrease post-operative opioid use (oxycodone/acetaminophen tablets; 5mg/325mg) for acute pain management in patients undergoing complete vestibulectomy with vaginal advancement flap for suspected NPV. Methods We studied the post-op opioid use of women who underwent complete vestibulectomy at our facility during the period January 1, 2019 through June 30, 2021. We assessed opioid use based on the patient's recall of the total oxycodone/acetaminophen tablets required in the first 30 days post-vestibulectomy. When possible, patients confirmed the use by counting tablets left in the pill container. Women scheduled to undergo vestibulectomy for suspected NPV were placed in the LiSWT study group if they agreed to undergo vestibular LiSWT treatment daily for the three business days immediately pre-operatively. Using the Urogold 100™MTS, LiSWT involved delivery of 1800 shocks to the vestibule per session, energy flux density 0.05-0.1 mJ/mm2, 3 Hz, membrane pressure 3. We compared the post-op opioid use by women in the LiSWT study group to the use by women who did not undergo pre-op LiSWT. Results Forty-five women (mean age 28 years; range 17 - 57) underwent complete vestibulectomy for suspected NPV during the 30 month period. Twenty women (mean age 27 +/- 9 years) agreed to undergo pre-op LiSWT and post-op opioid use was obtained in all. Twenty-five women (mean age 29 +/- 11 years) did not undergo pre-op LiSWT and opioid use was obtained in 19/25 (76%). Mean post-operative opioid use was 47 +/- 13 (range 25 - 90) tablets in those vestibulectomy patients who did not undergo pre-op vestibular LiSWT; opioid side effects included constipation, nausea, fainting, drowsiness, fatigue, and blurred vision. Mean post-op opioid use was 22 +/- 10 (range 1 - 26) tablets in the 20 vestibulectomy patients who did undergo pre-op vestibular LISWT sessions; opioid side effects were restricted to constipation, sleepiness, and nausea. Conclusions In this pilot study, pre-operative low intensity shockwave therapy decreased post-operative opioid use after complete vestibulectomy with vaginal advancement flap. While encouraging, more research is needed. Disclosure No

Ellagic acid inhibits proinflammatory intermediary manufacture by suppressing NF-κB/Akt, VEGF and activating Nrf-2/Caspase-3 signaling pathways in rat testicular damage: a new way for testicular damage cure and in silico approach

Ellagic acid (EA) has protective effect on testicular damage and this natural compound decreases oxidative damage. The present study aims to examine the preventive effect of ellagic acid (EA) against carbon tetrachloride (CCl4)-induced testicular tissue damage in rats. In testicular tissue, tumor necrosis factor-α (TNF-α), Nuclear factor erythroid-2 related factor 2 (Nrf-2), B-cell lymphoma-2 (Bcl-2), vascular endothelial growth factor (VEGF), Nuclear factor-kappa B (NF-κB), cysteine aspartic proteases (caspase-3) and protein kinase B (Akt) synthesis levels were analyzed by western blot method, reactive oxygen species (ROS) was measured by malondialdehyde (MDA) levels, Glutathione (GSH) level and catalase (CAT) by spectrophotometer. As a result, in comparison with the CCl4 group, caspase-3 and Nrf-2 protein synthesis levels increased in EA + CCl4 group, however, VEGF, Bcl-2, NF-κB, TNF-α and Akt protein synthesis levels decreased, EA application raised GSH levels and CAT activity, reduced MDA levels. In this study, in silico tools were applied to confirm the activity of EA against the cancer with macromolecules such as the above mentioned transcription factors. EA, turned out to show significant activity similarly to some cocrystal ligands, particularly against cancer. These results points out that EA can be used as a testicular damage cure drug in future.

Hypo-angiogenesis: a possible pathological factor in the development of dry age-related macular degeneration and a novel therapeutic target.

Angiogenesis causes severe vision loss in patients with exudative or wet forms of age-related macular degeneration (AMD). The pathogenesis involves upregulation of several proangiogenic factors, particularly the vascular endothelial growth factor (VEGF). Contrary to the pathogenesis of exudative AMD, molecular events leading to the development of dry AMD remain unclear. Dry AMD is characterized by loss of the retinal pigment epithelium (RPE). The mechanism that triggers RPE cell loss remains unclear. Choriocapillaris development is absent in mice with RPE-specific deletion of VEGF. Moreover, in later life, background VEGF secretion promotes the survival of the RPE and maintains choriocapillaris integrity. We hypothesized that reduced synthesis of VEGF (hypo-angiogenesis) or abnormalities in its receptors, VEGF receptor-1 (VEGFR1) and VEGFR2, may be involved in the pathogenesis of non-exudative AMD or dry AMD. If the concept of hypo-angiogenesis as a driver for dry AMD is proven, treatment with VEGF or induction of angiogenesis could be considered. Similar attempts at therapeutic angiogenesis have been actively investigated in cardiac and limb ischemia. The reasons for a patient developing exudative AMD or dry AMD remain poorly understood. Nevertheless, targeting increased VEGF production in patients with exudative AMD using anti-VEGF drugs is highly efficacious in preserving vision. Similarly, dry AMD may be a manifestation of reduced VEGF synthesis (hypo-angiogenesis) and subsequent decreased RPE cell survival. Experimental studies exploring the possibility of reduced VEGF secretion and/or increased receptor resistance/abnormality could pave the way for clinical trials of angiogenesis to treat dry AMD.

Angiogenesis during coronal pulp regeneration using rat dental pulp cells: Neovascularization in rat molars in vivo and proangiogenic dental pulp cell-endothelial cell interactions in vitro

Background/purposeAngiogenesis is considered a crucial event for dental pulp regeneration. The purpose of this study was to demonstrate neovascularization during coronal pulp regeneration in rat molars using rat dental pulp cells (rDPCs) and to examine whether rDPC-endothelial cell interactions promote proangiogenic capacity in vitro. Materials and methodsMaxillary first molars of Wistar rats (n = 42) were pulpotomized and rDPCs isolated from incisors were implanted with a porous poly (l-lactic acid) (PLLA) scaffold and hydrogel (Matrigel). After 3, 7, and 14 days, coronal pulp tissues were examined histologically and by nestin and CD146 immunohistochemistry. rDPCs and rat dermal microvascular endothelial cells (rDMECs) were cocultured for 4 days and vascular endothelial growth factor (VEGF) synthesis and angiogenic factor gene expression were determined by enzyme-linked immunosorbent assays and real-time polymerase chain reaction, respectively. Effects of cocultured medium on tube formation by rDMECs were also evaluated. ResultsImplantation of rDPC/PLLA/Matrigel induced coronal pulp regeneration with dentin bridge formation and arrangement of nestin-positive odontoblast-like cells at 14 days. PLLA/Matrigel without rDPCs did not induce pulp regeneration. CD146-positive blood vessels increased in density in the remaining pulp tissues at 3 and 7 days, and in the regenerated pulp tissue at 14 days. rDPC/DMEC coculture significantly promoted VEGF secretion and mRNA expression of nuclear factor-kappa B, angiogenic chemokine CXCL1, and chemokine receptor CXCR1. Cocultured medium significantly promoted tube formation. ConclusionCoronal pulp regeneration with rDPC/PLLA/Matrigel was accompanied by neovascularization. rDPC-rDMEC interactions may promote angiogenic activity represented by proangiogenic factor upregulation and tube formation in vitro.

Renal dysfunction and podocyturia in pre-eclampsia may be explained by increased urinary VEGF.

Pre-eclampsia has a major impact on renal function as shown by the development of proteinuria and podocyturia. How the systemic, soluble Fms-like tyrosine kinase-1 (sFlt-1)-driven inhibition of vascular endothelial growth factor (VEGF) activity detected in pre-eclampsia directly affects renal function remains unknown. The aim of the study was to clarify whether a non-canonical, renal-centred escape from VEGF inhibition in the case of pre-eclamptic pregnancy might have a direct impact on renal function. We evaluated plasma and urinary VEGF and placental growth factor (PlGF), plasma sFlt-1 and carbonic anhydrase IX (CAIX), albuminuria and podocyturia in 18 women with uncomplicated pregnancy, 21 with pre-eclampsia and 18 non-pregnant. The three groups were matched for age and the pregnant groups also for gestational age at enrolment. Plasma VEGF was reduced in uncomplicated (P = 0.001) and pre-eclamptic (P = 0.0003) pregnancies when compared with controls. In uncomplicated pregnancy, the dysfunction was balanced by an increase (P = 0.009) of plasma PlGF. Increased (P = 0.0001) plasma CAIX in pre-eclampsia was in line with hypoxia. Pre-eclampsia resulted in a paradoxical increase (P = 0.0004) of urinary excretion of VEGF. Urinary concentrations of VEGF and podocytes were correlated to each other (r2 = 0.48, P < 0.0005) but also to plasma sFlt-1 (r2 = 0.56, P < 0.0001 and r2 = 0.23, P = 0.03, respectively). In the case of pre-eclampsia, the systemic VEGF inhibition leads the kidney, possibly the podocyte, to increase the VEGF synthesis. The mechanisms leading to local VEGF overproduction or the overproduced VEGF itself are reasonably involved in the pathogenesis of podocyturia and, as a consequence, renal dysfunction in pre-eclampsia.

Transcriptional Regulation of Thrombin-Induced Endothelial VEGF Induction and Proangiogenic Response

Thrombin, the ligand of the protease-activated receptor 1 (PAR1), is a well-known stimulator of proangiogenic responses in vascular endothelial cells (ECs), which are mediated through the induction of vascular endothelial growth factor (VEGF). However, the transcriptional events underlying this thrombin-induced VEGF induction and angiogenic response are less well understood at present. As reported here, we conducted detailed promotor activation and signal transduction pathway studies in human microvascular ECs, to decipher the transcription factors and the intracellular signaling events underlying the thrombin and PAR-1-induced endothelial VEGF induction. We found that c-FOS is a key transcription factor controlling thrombin-induced EC VEGF synthesis and angiogenesis. Upon the binding and internalization of its G-protein-coupled PAR-1 receptor, thrombin triggers ERK1/2 signaling and activation of the nuclear AP-1/c-FOS transcription factor complex, which then leads to VEGF transcription, extracellular secretion, and concomitant proangiogenic responses of ECs. In conclusion, exposure of human microvascular ECs to thrombin triggers signaling through the PAR-1–ERK1/2–AP-1/c-FOS axis to control VEGF gene transcription and VEGF-induced angiogenesis. These observations offer a greater understanding of endothelial responses to thromboinflammation, which may help to interpret the results of clinical trials tackling the conditions associated with endothelial injury and thrombosis.

Effects of EGF-coated titanium surfaces on adhesion and metabolism of bisphosphonate-treated human keratinocytes and gingival fibroblasts

To assess the effects of epidermal growth factor (EGF)-coated titanium (Ti) discs on the adhesion and metabolism of keratinocytes and gingival fibroblasts exposed to nitrogen-containing bisphosphonates. Keratinocytes and fibroblasts were seeded (1 × 105 cells/disc) on Ti discs coated with EGF (100 nM). After 24 h, cells were exposed or not to sodium alendronate (SA) or zoledronic acid (ZA) at different concentrations (0 = control, 0.5, 1, or 5 μM) for 48 h. Cell adhesion to the substrates was evaluated by fluorescence microscopy. Cell viability (alamarBlue, n = 6) and synthesis of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2), and keratinocytes growth factor (KGF) (ELISA, n = 6) were assessed. Data were statistically analyzed by one-way ANOVA and Tukey tests (α = 0.05). Higher cell adhesion rate was observed when keratinocytes and fibroblasts were seeded onto EGF-coated discs in comparison to uncoated discs. ZA treatment hindered the adhesion of both cell lines on the Ti discs as well as reduced the viability and synthesis of VEGF, KGF and MMP-2 by cells (p < 0.05). SA treatment did not affect cell viability, but interfered negatively on the adhesion and synthesis of EGF and KGF by the cells (p < 0.05). EGF-coated surface increased cell viability and synthesis of growth factors as well as downregulated the synthesis of MMP-2 in comparison to control (p < 0.05). EGF applied on Ti surface improves the biological responses of oral mucosa cells exposed to SA and ZA. EGF-coating on titanium may be a suitable strategy to improve oral mucosa cellular events related to biological sealing, especially for patients under bisphosphonate therapy.

Influence of Supramolecular Chiral Hydrogel on Cellular Behavior of Endothelial Cells Under High-Glucose-Induced Injury

In order to manage the impaired wound healing of diabetic chronic wounds induced by high-glucose-damaged endothelial cells, a glucose-induced injured endothelial cell model is established in this research to explore the regulatory effects of a supramolecular chiral hydrogel on injured endothelial cells. Cellular behaviors of endothelial cells under different culture conditions are evaluated by CCK-8, 5-ethynyl-2′-deoxyuridine (EdU) staining, adhesion, and Transwell assays. The expression levels of angiogenesis-related markers, including nitric oxide, endothelial nitric oxide synthase (eNOS), and vascular endothelial growth factor (VEGF), are also assessed by enzyme-linked immune sorbent assay (ELISA) and the polymerase chain reaction (PCR). The results demonstrate that the left-handed chirality of the supramolecular chiral hydrogel can promote cell proliferation and enhance the adhesion and migration ability of impaired endothelial cells. Moreover, enhanced nitric oxide synthesis and elevated expression of eNOS and VEGF are observed in cells in the left-handed chiral environment. Thus, the left-handed supramolecular chiral hydrogel can regulate the cellular behavior of high-glucose-injured endothelial cells, including cell proliferation, adhesion, migration, and angiogenesis, offering the potential to promote diabetic wound healing.

HSP22 (HSPB8) positively regulates PGF2\u03b1-induced synthesis of interleukin-6 and vascular endothelial growth factor in osteoblasts

BackgroundHeat shock protein 22 (HSP22) belongs to class I of the small HSP family that displays ubiquitous expression in osteoblasts. We previously demonstrated that prostaglandin F2α (PGF2α), a potent bone remodeling factor, induces the synthesis of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) via p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase in osteoblast-like MC3T3-E1 cells. In the present study, we investigated whether HSP22 is implicated in the PGF2α-induced synthesis of IL-6 and VEGF and the mechanism of MC3T3-E1 cells.MethodsMC3T3-E1 cells were transfected with HSP22-siRNA. IL-6 and VEGF release was assessed by ELISA. Phosphorylation of p44/p42 MAP kinase and p38 MAP kinase was detected by Western blotting.ResultsThe PGF2α-induced release of IL-6 in HSP22 knockdown cells was significantly suppressed compared with that in the control cells. HSP22 knockdown also reduced the VEGF release by PGF2α. Phosphorylation of p44/p42 MAP kinase and p38 MAP kinase was attenuated by HSP22 downregulation.ConclusionsOur results strongly suggest that HSP22 acts as a positive regulator in the PGF2α-induced synthesis of IL-6 and VEGF in osteoblasts.

Uremic serum induces prothrombotic changes in venous endothelial cells and inflammatory changes in aortic endothelial cells

Background Uremia induces various pathologic changes in the endothelium. However, there is limited information about the differences of these effects in endothelial cells originating from different parts of the vascular tree. Methods The effect of uremic serum obtained from patients with end stage renal failure on the gene expression and secretory activity of venous endothelial cells (VEC) and aortic endothelial cells (AEC) was studied in in vitro culture. Results In VEC, the expression of genes regulating the synthesis of von Willebrand factor (vWF) was increased by 254% (p<.005), vascular endothelial growth factor (VEGF) synthesis by 150% (p<.001), tissue plasminogen activator (t-PA) synthesis by 62% (p<.005), platelet endothelial cell adhesion molecule by 89% (p<.005), and the expression of gene regulating interleukin-6 (IL-6) synthesis was reduced. In AEC, the expression of the gene regulating synthesis of IL-6 was increased by 174% (p<.001), and the expression of the other genes was reduced. The secretion of IL-6 was reduced in VEC by 38% (p<.01) and increased in AEC by 55% (p<.005). In VEC, increased synthesis of VEGF 64% (p<.001) vWF (+34%, p<.01), and t-PA (+53%, p<.002) was observed, and in AEC it was reduced. Conclusions VEC and AEC respond in different ways after exposure to uremic serum. VEC acquires the prothrombotic phenotype, whereas in AEC the inflammatory phenotype appears.