Angiogenesis--a new target for future therapy

Proangiogenic Azaphilones from the Marine-Derived Fungus Neopestalotiopsis sp. HN-1-6

Developing novel, safe, and efficient proangiogenic drugs is an important approach for the prevention and treatment of cardiovascular diseases. In this study, 4 new compounds, including 3 azaphilones (1-3) and 1 dihydroisocoumarin (4), as well as 13 known compounds (5-17), were isolated from the sea-mud-derived fungus Neopestalotiopsis sp. HN-1-6 from the Beibu Gulf of China. The structures of the new compounds were determined by NMR, MS, ECD, and NMR calculations. Compounds 3, 5, and 7 exhibited noteworthy proangiogenic activities in a zebrafish model at a concentration of 40 μM, without displaying cytotoxicity toward five human cell lines. In addition, some compounds demonstrated antibacterial effects against Staphylococcus aureus, Escherichia coli, and Candida albicans, with MIC values ranging from 64 μg/mL to 256 μg/mL.

Therapeutic Targeting of Hypoxia-Inducible Factors in Cancer

In the realm of cancer therapeutics, targeting the hypoxia-inducible factor (HIF) pathway has emerged as a promising strategy. This study delves into the intricate web of HIF-associated mechanisms, exploring avenues for future anticancer therapies. Framing the investigation within the broader context of cancer progression and hypoxia response, this article aims to decipher the pivotal role played by HIF in regulating genes influencing angiogenesis, cell proliferation, and glucose metabolism. Employing diverse approaches such as HIF inhibitors, anti-angiogenic therapies, and hypoxia-activated prodrugs, the research methodologically intervenes at different nodes of the HIF pathway. Findings showcase the efficacy of agents like EZN-2968, Minnelide, and Acriflavine in modulating HIF-1α protein synthesis and destabilizing HIF-1, providing preliminary proof of HIF-1α mRNA modulation and antitumor activity. However, challenges, including toxicity, necessitate continued exploration and development, as exemplified by ongoing clinical trials. This article concludes by emphasizing the potential of targeted HIF therapies in disrupting cancer-related signaling pathways.

Polycondensed Peptide-Based Polymers for Targeted Delivery of Anti-Angiogenic siRNA to Treat Endometriosis

Endometriosis (EM) is a prevalent gynecological disease characterized by the abnormal growth of tissue similar to the endometrium outside of the uterus. This condition is accompanied by the development of new blood vessels in endometriotic lesions. While surgical intervention is effective in removing endometriotic lesions, some patients require multiple surgeries. Therefore, finding non-surgical treatments for EM is of great interest. One of the promising approaches is anti-angiogenic therapy using siRNA-therapeutics to target the expression of the VEGFA gene. Peptide-based polymers have shown promise as siRNA delivery systems due to their biocompatibility and ease of modification. We conducted a study to evaluate the effectiveness of the R6p-cRGD peptide carrier as a non-viral vehicle for delivering siRNA to endothelial cells in vitro and endometrial implants in vivo. We investigated the physicochemical properties of the siRNA-complexes, assessed cellular toxicity, and examined the efficiency of GFP and VEGFA genes silencing. Furthermore, we tested the anti-angiogenic effects of these complexes in cellular and animal models. The transfection with siRNA complexes led to a significant increase in VEGFA gene knockdown efficiency and a decrease in the migration of endothelial cells. For the animal model, we induced endometriosis in rats by transplanting endometrial tissue subcutaneously. We evaluated the efficiency of anti-angiogenic therapy for EM in vivo using anti-VEGF siRNA/R6p-RGD complexes. During this assessment, we measured the volume of the implants, analyzed VEGFA gene expression, and conducted CD34 immunohistochemical staining. The results showed a significant decrease in the growth of endometriotic implants and in VEGFA gene expression. Overall, our findings demonstrate the potential of the R6p-cRGD peptide carrier as a delivery system for anti-angiogenic therapy of EM.

Nanotechnology in coronary heart disease

Coronary heart disease (CHD) is one of the major causes of death and disability worldwide, especially in low- and middle-income countries and among older populations. Conventional diagnostic and therapeutic approaches have limitations such as low sensitivity, high cost and side effects. Nanotechnology offers promising alternative strategies for the diagnosis and treatment of CHD by exploiting the unique properties of nanomaterials. In this review, we use bibliometric analysis to identify research hotspots in the application of nanotechnology in CHD and provide a comprehensive overview of the current state of the art. Nanomaterials with enhanced imaging and biosensing capabilities can improve the early detection of CHD through advanced contrast agents and high-resolution imaging techniques. Moreover, nanomaterials can facilitate targeted drug delivery, tissue engineering and modulation of inflammation and oxidative stress, thus addressing multiple aspects of CHD pathophysiology. We discuss the application of nanotechnology in CHD diagnosis (imaging and sensors) and treatment (regulation of macrophages, cardiac repair, anti-oxidative stress), and provide insights into future research directions and clinical translation. This review serves as a valuable resource for researchers and clinicians seeking to harness the potential of nanotechnology in the management of CHD. STATEMENT OF SIGNIFICANCE: Coronary heart disease (CHD) is the one of leading cause of death and disability worldwide. Nanotechnology offers new strategies for diagnosing and treating CHD by exploiting the unique properties of nanomaterials. This review uses bibliometric analysis to uncover research trends in the use of nanotechnology for CHD. We discuss the potential of nanomaterials for early CHD detection through advanced imaging and biosensing, targeted drug delivery, tissue engineering, and modulation of inflammation and oxidative stress. We also offer insights into future research directions and potential clinical applications. This work aims to guide researchers and clinicians in leveraging nanotechnology to improve CHD patient outcomes and quality of life.

Kinin receptors regulate skeletal muscle regeneration: differential effects for B1 and B2 receptors

OBJECTIVE AND DESIGN

After traumatic skeletal muscle injury, muscle healing is often incomplete and produces extensive fibrosis. Bradykinin (BK) reduces fibrosis in renal and cardiac damage models through the B2 receptor. The B1 receptor expression is induced by damage, and blocking of the kallikrein-kinin system seems to affect the progression of muscular dystrophy. We hypothesized that both kinin B1 and B2 receptors could play a differential role after traumatic muscle injury, and the lack of the B1 receptor could produce more cellular and molecular substrates for myogenesis and fewer substrates for fibrosis, leading to better muscle healing.

MATERIAL AND METHODS

To test this hypothesis, tibialis anterior muscles of kinin receptor knockout animals were subjected to traumatic injury. Myogenesis, angiogenesis, fibrosis, and muscle functioning were evaluated.

RESULTS

Injured B1KO mice showed a faster healing progression of the injured area with a larger amount of central nucleated fiber post-injury when compared to control mice. In addition, they exhibited higher neovasculogenic capacity, maintaining optimal tissue perfusion for the post-injury phase; had higher amounts of myogenic markers with less inflammatory infiltrate and tissue destruction. This was followed by higher amounts of SMAD7 and lower amounts of p-SMAD2/3, which resulted in less fibrosis. In contrast, B2KO and B1B2KO mice showed more severe tissue destruction and excessive fibrosis. B1KO animals had better results in post-injury functional tests compared to control animals.

CONCLUSIONS

We demonstrate that injured skeletal muscle tissues have a better repair capacity with less fibrosis in the presence of B2 receptor and absence of B1 receptor, including better performances in functional tests.

Investigation of anti-proliferative and anti-angiogenic properties of Parkia javanica bark and fruit extracts in zebrafish

The use of herbal products as traditional medicines has been a practice in India for centuries. Due to high ethnic diversity, the pool of herbal medicines is enormous, and they are often preferred over modern medicines in certain parts of the country. Cancer is one of the major non-communicable diseases affecting people worldwide. Despite considerable research, cancer is a disease that is still not understood completely, and there have been constant efforts towards the identification of novel drugs or approaches in cancer management. Parkia javanica, an important medicinal plant and a rich source of flavonoids and terpenoids, is widely studied for its antioxidant and anti-inflammatory activities. Traditionally, the fruit and bark extracts of P. javanica find use as home remedy for dysentery and piles in NE India. Moreover, the fruits are consumed by the people of North-East (NE) India as vegetables, either in steamed or cooked form. In this study, crude extracts of P. javanica fruit and bark were obtained, the sub-lethal dose was determined and were then analyzed for anti-proliferative and anti-angiogenic properties using a battery of assays in zebrafish embryos. The sub-lethal concentration 50 (LC50) was found to be 28.66 mg/L and 346.66 mg/L for bark and fruit extract respectively, indicating a decreased toxicity of the fruit extract compared to that of the bark. The anti-proliferative and anti-angiogenic properties were more pronounced for the fruit extract compared to the bark extract. Although preliminary, the results of the study suggest that P. javanica fruits possess potent anti-angiogenic and anti-proliferative properties, which can be further studied for the isolation of active phytochemicals for use as therapeutic agents.

Quercetin modulates signal transductions and targets non-coding RNAs against cancer development

In recent decades, various investigations have indicated that natural compounds have great potential in the prevention and treatment of different chronic disorders including different types of cancer. As a bioactive flavonoid, Quercetin (Qu) is a dietary ingredient enjoying high pharmacological values and health-promoting effects due to its antioxidant and anti-inflammatory characterization. Conclusive in vitro and in vivo evidence has revealed that Qu has great potential in cancer prevention and development. Qu exerts its anticancer influences by altering various cellular processes such as apoptosis, autophagy, angiogenesis, metastasis, cell cycle, and proliferation. In this way, Qu by targeting numerous signaling pathways as well as non-coding RNAs regulates several cellular mechanisms to suppress cancer occurrence and promotion. This review aimed to summarize the impact of Qu on the molecular pathways and non-coding RNAs in modulating various cancer-associated cellular mechanisms.

Zebrafish as a Model of Cardiac Pathology and Toxicity: Spotlight on Uremic Toxins

Chronic kidney disease (CKD) is an increasing health care problem. About 10% of the general population is affected by CKD, representing the sixth cause of death in the world. Cardiovascular events are the main mortality cause in CKD, with a cardiovascular risk 10 times higher in these patients than the rate observed in healthy subjects. The gradual decline of the kidney leads to the accumulation of uremic solutes with a negative effect on every organ, especially on the cardiovascular system. Mammalian models, sharing structural and functional similarities with humans, have been widely used to study cardiovascular disease mechanisms and test new therapies, but many of them are rather expensive and difficult to manipulate. Over the last few decades, zebrafish has become a powerful non-mammalian model to study alterations associated with human disease. The high conservation of gene function, low cost, small size, rapid growth, and easiness of genetic manipulation are just some of the features of this experimental model. More specifically, embryonic cardiac development and physiological responses to exposure to numerous toxin substances are similar to those observed in mammals, making zebrafish an ideal model to study cardiac development, toxicity, and cardiovascular disease.

Transcription factor Foxp1 stimulates angiogenesis in adult rats after myocardial infarction

Forkhead box protein P1 (FoxP1) is essential for cardiac development and the regulation of neovascularization, but its potential for cardiac angiogenesis has not been explored. This study aims to investigate the angiogenic role of FoxP1 in a rat model of myocardial infarction (MI). Adult male rats were subjected to MI, and Foxp1 was knocked down with lentivirus FoxP1 siRNA. Endothelial cell proliferation, angiogenesis, and cardiac function were also assessed. Cell scratch assay and tubule formation analysis were used to detect the migration ability and tube formation ability of human umbilical vein endothelial cells (HUVECs). Compared with that in the sham group, results showed that the expression of FoxP1 was significantly increased in the MI group. Foxp1 knockdown decreases FoxP1 expression, reduces angiogenesis, and increases collagen deposition. When Foxp1 was knocked down in HUVECs using FoxP1 siRNA lentivirus, cell proliferation, migration, and tube formation abilities decreased significantly. Our study showed that FoxP1 elicits pleiotropic beneficial actions on angiogenesis in the post-MI heart by promoting the proliferation of endothelial cells. FoxP1 should be considered a candidate for therapeutic cardiac angiogenesis.

Acriflavine, an Acridine Derivative for Biomedical Application: Current State of the Art

Acriflavine (ACF) has been known for years as an antibacterial drug. The identification of key oncogenic mechanisms has brought, in recent years, a significant increase in studies on ACF as a multipurpose drug that would improve the prognosis for cancer patients. ACF interferes with the expression of the hypoxia inducible factor, thus acting on metastatic niches of tumors and significantly enhancing the effects of other anticancer therapies. It has been recognized as the most potent HIF-1 inhibitor out of the 336 drugs approved by the FDA. This work presents up-to-date knowledge about the mechanisms of action of ACF and its related prodrug systems in the context of anticancer and SARS-CoV-2 inhibitory properties. It explains the multitask nature of this drug and suggests mechanisms of ACF’s action on the coronavirus. Other recent reports on ACF-based systems as potential antibacterial and antiviral drugs are also described.

The Angiogenic Balance and Its Implications in Cancer and Cardiovascular Diseases: An Overview

Angiogenesis is the process of developing new blood vessels from pre-existing ones. This review summarizes the main features of physiological and pathological angiogenesis and those of angiogenesis activation and inhibition. In healthy adults, angiogenesis is absent apart from its involvement in female reproductive functions and tissue regeneration. Angiogenesis is a complex process regulated by the action of specific activators and inhibitors. In certain diseases, modulating the angiogenic balance can be a therapeutic route, either by inhibiting angiogenesis (for example in the case of tumor angiogenesis), or by trying to activate the process of new blood vessels formation, which is the goal in case of cardiac or peripheral ischemia.

Biological aspects in controlling angiogenesis: current progress

All living beings continue their life by receiving energy and by excreting waste products. In animals, the arteries are the pathways of these transfers to the cells. Angiogenesis, the formation of the arteries by the development of pre-existed parental blood vessels, is a phenomenon that occurs naturally during puberty due to certain physiological processes such as menstruation, wound healing, or the adaptation of athletes' bodies during exercise. Nonetheless, the same life-giving process also occurs frequently in some patients and, conversely, occurs slowly in some physiological problems, such as cancer and diabetes, so inhibiting angiogenesis has been considered to be one of the important strategies to fight these diseases. Accordingly, in tissue engineering and regenerative medicine, the highly controlled process of angiogenesis is very important in tissue repairing. Excessive angiogenesis can promote tumor progression and lack of enough angiogensis can hinder tissue repair. Thereby, both excessive and deficient angiogenesis can be problematic, this review article introduces and describes the types of factors involved in controlling angiogenesis. Considering all of the existing strategies, we will try to lay out the latest knowledge that deals with stimulating/inhibiting the angiogenesis. At the end of the article, owing to the early-reviewed mechanical aspects that overshadow angiogenesis, the strategies of angiogenesis in tissue engineering will be discussed.

Small GTPases and Their Regulators: A Leading Road toward Blood Vessel Development in Zebrafish

Members of the Ras superfamily have been found to perform several functions leading to the development of eukaryotes. These small GTPases are divided into five major subfamilies, and their regulators can “turn on” and “turn off” signals. Recent studies have shown that this superfamily of proteins has various roles in the process of vascular development, such as vasculogenesis and angiogenesis. Here, we discuss the role of these subfamilies in the development of the vascular system in zebrafish.

Dezocine Has the Potential to Regulate the Clinical and Biological Features of Tumors

Cancer is the second leading cause of death following ischemic heart disease in the world and the primary clinical, social and economic burden. Surgical resection is the main measure for the treatment of the vast majority of solid tumors. However, the recurrence and metastasis of tumors occur at different periods after surgery in many cases undergoing radical tumor surgery, which is the main cause of death of tumor patients. Moreover, tumor patients are prone to suffer from mental depression, which may increase the morbidity and mortality of tumors. Tumors have a series of clinical biological signs with the following five main features: postoperative pain and cancerous pain; suppression of antitumor immunity; angiogenesis in tumors; proliferation, growth and metastasis of tumors; and mental depression. Surgery is the first treatment in the majority of cancer patients with solid tumors. Opioids are required for anesthesia and postoperative analgesia. For cancerous pain control, patients undergo surgery, and their quality of life of is improved. However, traditional opioids, such as morphine, may inhibit antitumor immunity, induce vascular growth of tumors and promote the proliferation, invasion and migration of cancer cells, and traditional opioids can induce a risk of somatic dependence. However, studies have found that not all opioids share the effects of immunosuppression, tumor proliferation promotion and angiogenesis induction. Dezocine, a novel opioid with specific pharmacological mechanisms, has been demonstrated to regulate the five clinical and biological features of tumors. We reviewed the preclinical and clinical studies of dezocine on postoperative pain and cancer pain in tumor patients as well as the immune system, tumor angiogenesis, tumor proliferation, tumor growth, tumor metastasis and mental depression. We proposed that dezocine may be the best choice of opioids for anesthesia and analgesia in cancer patients.

Shexiang Tongxin Dropping Pills Promote Macrophage Polarization-Induced Angiogenesis Against Coronary Microvascular Dysfunction via PI3K/Akt/mTORC1 Pathway

Background: Accumulating evidence suggests that coronary microvascular dysfunction (CMD) is one of the important causes of coronary artery diseases. Angiogenesis can effectively improve CMD by increasing blood supply capacity, recovering cardiac function and poor hemodynamics. Clinical studies have approved Shexiang Tongxin dropping pill (STDP), which has exerted remarkable roles on ameliorating CMD, but the effects and mechanisms of STDPs on angiogenesis have not been clarified. Purpose: The purpose of this study was to elucidate the effects and potential mechanisms of STDPs on macrophage polarization-induced angiogenesis against CMD. Methods: Echocardiography, optical microangiography (OMAG), and histological examination were applied to evaluate cardioprotection and proangiogenic effects of STDPs on left anterior descending (LAD) ligation-induced CMD rats. In vitro, oxygen-glucose deprivation-reperfusion (OGD/R)-induced HUVEC model and LPS-stimulated bone marrow-derived macrophage (BMDM) model were established to observe the effects of STDPs on angiogenesis and M2 macrophage polarization. Results: STDPs improved cardiac function, increased microvascular density, and the number of M2 macrophages in the heart of CMD rats. In vitro, STDPs accelerated the proliferation, migration, and tube formation in OGD/R-induced HUVECs similar to the effects of VEGF-A. Furthermore, in LPS-stimulated BMDMs model, STDPs modulated M2 macrophage polarization and increased VEGF-A release via the PI3K/AKT/mTORC1 pathway. Conclusion: STDPs promoted macrophage polarization-induced angiogenesis against CMD via the PI3K/Akt/mTORC1 pathway. Our results demonstrated that the phenotype transformation of macrophages and stimulating the secretion of VEGF-A may be applied as novel cardioprotective targets for the treatment of CMD.

Antioxidant and Anti-inflammatory Properties of Resveratrol in Diabetic Nephropathy: A Systematic Review and Meta-analysis of Animal Studies

Background: Accumulated experimental evidence suggests that resveratrol may have an effect on diabetic nephropathy by inhibiting inflammation and decreasing oxidative stress. However, the credibility of the evidence for this practice is unclear. Thus, we aimed to perform a systematic review and meta-analysis of animal studies to evaluate the antioxidant and anti-inflammatory properties of resveratrol when used in the treatment of diabetic nephropathy.

Methods: Electronic bibliographic databases including PubMed, EMBASE, and Web of Science were searched for relevant studies. The methodological quality of animal studies was assessed based on the SYstematic Review Center for Laboratory animal Experimentation Risk of Bias (SYRCLE’s RoB) tool. A meta-analysis was performed based on the Cochrane Handbook for Systematic Reviews of Interventions by using RevMan 5.4 software. This study was registered within International Prospective Register of Systematic Reviews (PROSPERO) as number CRD42021293784.

Results: Thirty-six qualified studies involving 726 animals were included. There was a significant association of resveratrol with the levels of blood glucose (BG), serum creatinine (Scr), blood urea nitrogen (BUN), catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), and interleukin-1β (IL-1β). Nevertheless, resveratrol treatment did not effectively decrease the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In addition, more remarkable antioxidant and hypoglycemic effects were observed in type 2 diabetic nephropathy rather than in type 1 diabetic nephropathy based on subgroup analysis.

Conclusion: In this meta-analysis, resveratrol can exert its antioxidant activities by reducing the levels of MDA and recovering the activities of SOD, CAT, GSH, and GPx. With regard to pro-inflammatory cytokines, resveratrol had a positive effect on the reduction of IL-1β. However, the analysis indicated that resveratrol had no effect on IL-6 and TNF-α levels, probably because of the methodological quality of the studies and their heterogeneity. Current evidence supports the antioxidant and anti-inflammatory properties of resveratrol, but its relationship with the levels of some inflammatory cytokines such as IL-6 and TNF-α in animals with diabetic nephropathy needs further elucidation.

Natural Products with Activity against Lung Cancer: A Review Focusing on the Tumor Microenvironment

Lung cancer is one of the most prevalent malignancies worldwide. Despite the undeniable progress in lung cancer research made over the past decade, it is still the leading cause of cancer-related deaths and continues to challenge scientists and researchers engaged in searching for therapeutics and drugs. The tumor microenvironment (TME) is recognized as one of the major hallmarks of epithelial cancers, including the majority of lung cancers, and is associated with tumorigenesis, progression, invasion, and metastasis. Targeting of the TME has received increasing attention in recent years. Natural products have historically made substantial contributions to pharmacotherapy, especially for cancer. In this review, we emphasize the role of the TME and summarize the experimental proof demonstrating the antitumor effects and underlying mechanisms of natural products that target the TME. We also review the effects of natural products used in combination with anticancer agents. Moreover, we highlight nanotechnology and other materials used to enhance the effects of natural products. Overall, our hope is that this review of these natural products will encourage more thoughts and ideas on therapeutic development to benefit lung cancer patients.

Preparation and evaluation of conjugate nanogels of glycyl-prednisolone with natural anionic polysaccharides as anti-arthritic delivery systems

Although prednisolone (PD) is used as an anti-arthritis drug due to its rapid and strong anti-inflammatory potential, its frequent and large dosing often brings about adverse effects. Therefore, targeting therapy has attracted increasing attention to overcome such adverse effects. In the present study, nanogels (NGs) composed of macromolecule-PD conjugates were developed as a novel targeting delivery system, and their anti-inflammatory potential was examined. Conjugates were prepared by carbodiimide coupling between glycyl-prednisolone (GP) and the natural anionic polysaccharides, alginic acid (AL) and hyaluronic acid (HA). NGs were produced by the evaporation of organic solvent from the conjugate solution. The obtained NGs, named AL-GP-NG and HA-GP-NG, respectively, were examined for particle characteristics, in vitro release, pharmacokinetics, and in vivo efficacy. Both NGs were several hundred nanometers in size, had negative zeta potentials, and several % (w/w) drug contents. They released PD gradually at pH 7.4 and 6. They exhibited fairly good retention in the systemic circulation. In the efficacy examination using rats with adjuvant-induced arthritis, both NGs showed the stronger and more prolonged suppression of paw inflammation than PD alone. These suggested that the present NGs should be possibly useful as anti-arthritis targeting therapeutic systems.

Snake venom vascular endothelial growth factors (svVEGFs): Unravelling their molecular structure, functions, and research potential

Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis, a physiological process characterized by the formation of new vessels from a preexisting endothelium. VEGF has also been implicated in pathologic states, such as neoplasias, intraocular neovascular disorders, among other conditions. VEGFs are distributed in seven different families: VEGF-A, B, C, D, and PIGF (placental growth factor), which are identified in mammals; VEGF-E, which are encountered in viruses; and VEGF-F or svVEGF (snake venom VEGF) described in snake venoms. This is the pioneer review of svVEGF family, exploring its distribution among the snake venoms, molecular structure, main functions, and potential applications.

A Narrative Review of Current Understanding of the Pathophysiology of Polycystic Ovary Syndrome: Focus on Plausible Relevance of Vitamin D

Polycystic ovarian syndrome (PCOS) is the most prevalent endocrinopathy of reproductive years. Salient features in presentation of patients PCOS include menstrual dysfunction, hyperandrogenism and/or polycystic appearance of ovaries on ultrasound. While the diagnosis of PCOS depends on presence of specified criteria, misdiagnoses are common. Despite years of extensive research, the exact aetiology of PCOS remains largely unknown. In the past decade, apart from insulin resistance and hyperandrogenemia, anti-mullerian hormone (AMH), an important marker of ovarian reserve, and vascular endothelial growth factor (VEGF), a crucial factor in angiogenesis, have been examined as plausible players of causative relevance for PCOS. Vitamin D, a sex-steroid hormone that is universally known for its relevance for skeletal health, has received increasing attention due to growing evidence supporting its pivotal in reproductive physiology and in PCOS. In this review we summarize our current understanding of the mechanisms relevant to the pathophysiology of PCOS and examine the role of vitamin D signalling in this context.

New bis([1,2,4]triazolo)[4,3-a:3',4'-c]quinoxaline derivatives as VEGFR-2 inhibitors and apoptosis inducers: Design, synthesis, in silico studies, and anticancer evaluation

A new series of bis([1,2,4]triazolo)[4,3-a:3',4'-c]quinoxaline derivatives were designed and synthesized to have the main essential pharmacophoric features of VEGFR-2 inhibitors. VEGFR-2 inhibitory activities were assessed for the designed compounds. In addition, cytotoxic activity was evaluated for all derivatives against two human cancer cell lines namely, HepG-2 and MCF-7. The most cytotoxic compound 20 h was subjected to further biological investigations including cell cycle, apoptosis, caspase-3, caspase-9, BAX, and Bcl-2 analyses. Different in silico studies as docking, ADMET and toxicity were carried out. The results exhibited that compounds 20b, 20e, 20h and20mshowed promising VEGFR-2 inhibitory activities with IC₅₀values of 5.7, 6.7, 3.2, and 3.1 µM, respectively. Moreover, these promising members exhibited the highest antiproliferative activities against the two cell lines with IC₅₀values ranging from 3.3 to 14.2 µM, comparing to sorafenib (IC₅₀ = 2.17 and 3.43 µM against HepG2 and MCF-7, respectively). Additionally, compound 20h induced cell cycle arrest of HepG2 cells at G2/M phase. Also, such compound increased the progress of apoptosis by 3.5-fold compared to the control. As well, compound 20h showed a significant increase in the level of caspase-3 (2.07-fold), caspase-9 (1.72-fold), and BAX (1.83-fold), and a significant decrease in Bcl-2 level (1.92-fold). The in silico studies revealed that the synthesized compounds have binding pattern like that of sorafenib.

Design, microwave assisted synthesis, and molecular modeling study of some new 1,3,4-thiadiazole derivatives as potent anticancer agents and potential VEGFR-2 inhibitors

A green and efficient method was developed for the synthesis of 1,3,4-thiadiazole based compounds under microwave (MW) activation. The nucleophile N-(5-amino-1,3,4-thiadiazol-2-yl)thiophene-2-carboxamide (3) was synthesized and reacted with different carbon electrophilic reagents to afford thiadiazolo-pyrimidine or imidazolo-thiadiazoline derivatives (4-6 and 8), respectively. Furthermore, a one-pot reaction of 3 with p-chlorobenzaldehyde and different carbon electrophile/ or nucleophiles under microwave irradiation yields the cyclic thiadiazolo-pyrimidine derivatives 10-15. Additionally, nucleophilic substitution of aromatic amines and/or potassium salts of some heterocyclic compounds with chloroacetamido-thiadiazole 6 yields derivatives 16-20. All the new derivatives were synthesized by both conventional and MW irradiation methods. All the new 1,3,4-thiadiazole derivatives were evaluated against four cancer cell lines, HepG-2, MCF-7, HCT-116, and PC-3. The anti-proliferative activity of most of the synthesized compounds exhibited excellent broad-spectrum cytotoxic activity against the cancer cell lines with IC₅₀ values ranging from 3.97 to 9.62 μM. Moreover, the enzymatic assessment of five derivatives (2,4b, 6, 8, 9a) against VEGFR-2 tyrosine kinase showed significant inhibitory activities with IC₅₀ of 11.5, 8.2, 10.3, 10.5 and 9.4 nM respectively. Further studies revealed the ability of compound 9a to have a strong DNA-binding affinity of 36.06 μM via DNA/methyl green assay. Moreover, molecular docking study was carried out to reveal the binding interactions of compounds in the binding site of VEGFR-2 enzyme explaining the significant inhibitory activity of these derivatives. Finally, ADME/Tox studies was performed to predict the pharmacokinetics of the synthesized compounds.

Organic/inorganic nanohybrids rejuvenate photodynamic cancer therapy

The development of nanotechnology has changed the 100-year-old paradigm of photodynamic therapy (PDT), in which organic/inorganic hybrid nanomaterials have made great contributions. In this review, we first describe the mechanisms of PDT and discuss the limitations of conventional PDT. On this basis, we summarize recent progress in organic/inorganic nanohybrids-based photodynamic agents, highlighting how these nanohybrids can be programmed to overcome challenges in photodynamic cancer therapy.

Seasonal expressions of VEGF and its receptors VEGFR1 and VEGFR2 in the prostate of the wild ground squirrels (<em>Spermophilus dauricus</em>)

As a vital male accessory reproductive gonad, the prostate requires vascular endothelial growth factors for promoting its growth and development. In this study, we investigated the localizations and expressions of vascular endothelial growth factor (VEGF) and its receptors including VEGF-receptor1 (VEFGR1) and VEGF-receptor2 (VEGFR2) in the prostate of the wild ground squirrels during the breeding and the non-breeding seasons. The values of total prostate weight and volume in the breeding season were higher than those in the non-breeding season. Histological observations showed that the exocrine lumens of the prostate expanded in the breeding season and contracted in the non-breeding season. The mRNA expression levels of VEGF and VEGFR2 in the prostate were higher in the breeding season than those in the non-breeding season, but the mRNA expression level of VEGFR1 had no significant change between the breeding and non-breeding seasons. Immunohistochemical results revealed that VEGF, VEGFR1 and VEGFR2 were presented in epithelial and stromal cells during the breeding and non-breeding seasons. In addition, the microvessels of the prostate were widely distributed and the number of microvessels increased obviously in the breeding season, while decreased sharply in the non-breeding season. These results suggested that expression levels of VEGF and VEGFR2 might be correlated with seasonal changes in morphology and functions of the prostate, and VEGF might serve as pivotal regulators to affect seasonal changes in the prostate functions of the wild male ground squirrels via an autocrine/paracrine pathway.

Increased angiogenesis and migration of dermal microvascular endothelial cells from patients with psoriasis

Psoriasis displays both increased angiogenesis and microvascular dilation in the skin, while human dermal microvascular endothelial cells (HDMECs) are involved in angiogenesis and microvascular dilation. Whether the functions of HDMECs are altered in psoriatic skin versus healthy skin remain unknown. Here, we isolated HDMECs from the skin of 10 patients with psoriasis and 10 healthy subjects and compared angiogenesis, proliferation, migration and cell metabolism between psoriatic HDMECs and normal HDMECs. We found that the morphology of primary HDMECs was comparable between psoriatic HDMECs and normal HDMECs. After passage, psoriatic HDMECs displayed larger cell size and wider intercellular space. In addition to DiI-Ac-LDL (DiI-labelled acetylated low-density lipoprotein) uptake, expression levels of CD31, vWF (von Willebrand factor) and LYVE-1 were comparable in psoriatic HDMECs versus normal HDMECs. However, psoriatic HDMECs exhibited increased tube formation (numbers of nodes and meshes, p < 0.05) and migration (numbers of migrated cells, p < 0.001) and reductions in proliferation (growth rates, p < 0.05) and energy metabolism (oxygen consumption rate and extracellular acidification rate, p < 0.05) compared with normal HDMECs. Therefore, psoriatic HDMECs display an increased angiogenesis and migration and decreased proliferation and metabolic activity, suggesting a pathogenic role of HDMECs in psoriasis.

Treatment of Mild-to-Moderate Plaque Psoriasis with a New 650-Microsecond 1064-nm Nd:YAG Laser: Clinical and Dermoscopic Assessment

INTRODUCTION

About 70-80% of patients with psoriasis suffer from mild disease, and new modalities of topical treatment are urgently needed. This study aims to evaluate the effectiveness of 650-microsecond 1064-nm Nd:YAG laser in the therapy of psoriatic plaques and assess the utility of dermoscopy in predicting treatment response.

METHODS

Ten patients (mean age 37.4 ± 16.2 years) with stable plaque-type psoriasis were enrolled. The microsecond Nd:YAG laser treatment was applied to representative plaques on day 0, 7, 14, and 21. Clinical and dermoscopic photographs were performed at each session and follow-up visit (day 28). The disease severity was assessed using modified Psoriasis Area and Severity Index (mPASI) and Investigator Global Assessment (IGA). Patients were asked to rate the intensity of subjective symptoms, tolerability, and final outcome of the treatment.

RESULTS

Significant improvement of all mPASI components was observed, although the maximal mean reduction of total mPASI was only 30.3%. At baseline, three patients were assessed as "moderate" and seven as "mild" according to IGA, while on day 28, eight patients were scored as "mild" and two as "almost clear." Complete resolution of itching was achieved in all patients. Local adverse reactions were also observed, which resulted in moderate tolerance of treatment in four patients. Three participants reported marked improvement on day 28, although 30% of patients observed no benefit. All subjects with dotted vessels, linear vessels, or hemorrhagic spots under dermoscopy at baseline reported some improvement after laser therapy. Three out of six patients with globular vessels were unresponsive to Nd:YAG laser.

CONCLUSIONS

Microsecond Nd:YAG laser treatment may provide some improvement of psoriatic plaques, but its routine applicability seems to be limited due to ambiguous efficacy and local adverse reactions. Dermoscopy may be useful in identifying patients who will benefit from the procedure.

The Protective and Reparative Role of Colony-Stimulating Factors in the Brain with Cerebral Ischemia/Reperfusion Injury

Stroke is a debilitating disease and has the ability to culminate in devastating clinical outcomes. Ischemic stroke followed by reperfusion entrains cerebral ischemia/reperfusion (I/R) injury, which is a complex pathological process and is associated with serious clinical manifestations. Therefore, the development of a robust and effective poststroke therapy is crucial. Granulocyte colony-stimulating factor (GCSF) and erythropoietin (EPO), originally discovered as hematopoietic growth factors, are versatile and have transcended beyond their traditional role of orchestrating the proliferation, differentiation, and survival of hematopoietic progenitors to one that fosters brain protection/neuroregeneration. The clinical indication regarding GCSF and EPO as an auspicious therapeutic strategy is conferred in a plethora of illnesses, including anemia and neutropenia. EPO and GCSF alleviate cerebral I/R injury through a multitude of mechanisms, involving antiapoptotic, anti-inflammatory, antioxidant, neurogenic, and angiogenic effects. Despite bolstering evidence from preclinical studies, the multiple brain protective modalities of GCSF and EPO failed to translate in clinical trials and thereby raises several questions. The present review comprehensively compiles and discusses key findings from in vitro, in vivo, and clinical data pertaining to the administration of EPO, GCSF, and other drugs, which alter levels of colony-stimulating factor (CSF) in the brain following cerebral I/R injury, and elaborates on the contributing factors, which led to the lost in translation of CSFs from bench to bedside. Any controversial findings are discussed to enable a clear overview of the role of EPO and GCSF as robust and effective candidates for poststroke therapy.

Defining Pre-Clinical Psoriatic Arthritis in an Integrated Dermato-Rheumatology Environment

In excess of three quarters of patients with psoriatic arthritis (PsA) have preceding psoriasis (PsO), which offers a clinical biomarker for the recognition of early PsA. Numerous surveys have shown a remarkably high frequency of clinically occult musculoskeletal symptoms in psoriasis patients. Imaging studies, particularly ultrasound, show a high prevalence of subclinical enthesitis and other inflammatory changes in psoriasis subjects. Since a serum biomarker, such as the case of anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis, neither exists nor seems biologically plausible at this point, this article explores how integration of rheumatological and dermatological assessment can be facilitated for the early recognition of potential PsA. Given that scalp disease is a PsA predictor, but may be managed in the community, then a particular need to access this group is needed. An integrated approach between rheumatology and dermatology can involve joint clinics, parallel clinics with discussion of relevant cases or virtual contact between specialties. Early therapy evaluation and integrated strategies have considerable implications for minimizing suffering and joint damage in PsA.

Advances in Therapeutic Targeting of Cancer Stem Cells within the Tumor Microenvironment: An Updated Review

Despite great strides being achieved in improving cancer patients' outcomes through better therapies and combinatorial treatment, several hurdles still remain due to therapy resistance, cancer recurrence and metastasis. Drug resistance culminating in relapse continues to be associated with fatal disease. The cancer stem cell theory posits that tumors are driven by specialized cancer cells called cancer stem cells (CSCs). CSCs are a subpopulation of cancer cells known to be resistant to therapy and cause metastasis. Whilst the debate on whether CSCs are the origins of the primary tumor rages on, CSCs have been further characterized in many cancers with data illustrating that CSCs display great abilities to self-renew, resist therapies due to enhanced epithelial to mesenchymal (EMT) properties, enhanced expression of ATP-binding cassette (ABC) membrane transporters, activation of several survival signaling pathways and increased immune evasion as well as DNA repair mechanisms. CSCs also display great heterogeneity with the consequential lack of specific CSC markers presenting a great challenge to their targeting. In this updated review we revisit CSCs within the tumor microenvironment (TME) and present novel treatment strategies targeting CSCs. These promising strategies include targeting CSCs-specific properties using small molecule inhibitors, immunotherapy, microRNA mediated inhibitors, epigenetic methods as well as targeting CSC niche-microenvironmental factors and differentiation. Lastly, we present recent clinical trials undertaken to try to turn the tide against cancer by targeting CSC-associated drug resistance and metastasis.

Recent Advances in Nanostrategies Capable of Overcoming Biological Barriers for Tumor Management

Engineered nanomaterials have been extensively employed as therapeutics for tumor management. Meanwhile, the complex tumor niche along with multiple barriers at the cellular level collectively hinders the action of nanomedicines. Here, the advanced strategies that hold promise for overcoming the numerous biological barriers facing nanomedicines are summarized. Starting from tumor entry, methods that promote tissue penetration of nanomedicine and address the hypoxia issue are also highlighted. Then, emphasis is given to the significance of overcoming both physical barriers, such as membrane-associated efflux pumps, and biological features, such as resistance to apoptosis. The pros and cons for an individual approach are presented. In addition, the associated technical problems are discussed, along with the importance of balancing the therapeutic merits and the additional cost of sophisticated nanomedicine designs.

Association of ITGAV polymorphisms and risk of rheumatoid arthritis: evidence from a meta-analysis

OBJECTIVE

Currently published papers regarding the relationship between integrin alpha V (ITGAV) gene polymorphisms and rheumatoid arthritis (RA) are contradictory. The aim of this meta-analysis was to evaluate the associations between the ITGAV gene polymorphisms and RA risk.

METHODS

Comprehensive literature search based on four electronic databases was applied to retrieve all related data. Two independent reviewers screened each article for eligibility according to the predetermined inclusion criteria. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to assess associations between ITGAV gene polymorphisms and RA.

RESULTS

Six articles involving 5794 RA patients and 5297 healthy controls were included in this meta-analysis. The combined data indicated that rs3911238, rs3738919, rs3768777, and rs10174098 in ITGAV gene were not associated with RA risk in the overall population. However, stratification analysis by ethnicity suggested that rs3768777 was related with risk of RA among Caucasian population (OR 3.51, 95%CI 2.06, 5.97; P < 0.0001), but not among Asian population (OR 1.06, 95%CI 0.67, 1.69; P = 0.81).

CONCLUSIONS

Our meta-analysis confirmed that the ITGAV gene rs3768777 polymorphisms might be a risk factor among Caucasians. However, larger-scale studies in Caucasian population are still warranted to confirm the findings of our study.

Genetic variants of VEGFR-1 gene promoter in acute myocardial infarction

BACKGROUND

Coronary artery disease (CAD) including acute myocardial infarction (AMI) is a common complex disease caused by atherosclerosis. Vascular epithelial growth factor receptor-1 (VEGFR-1) stimulates angiogenesis and vascular permeability, and functions as a decoy to sequester VEGF and prevent initiation of intracellular signaling. VEGFR-1 knockout mice exhibit significantly higher mortality due to heart failure, cardiac hypertrophy, and cardiac dysfunction. An evident increase in macrophage infiltration and cardiac fibrosis are also observed after transverse aortic constriction. Therefore, VEGFR-1 gene variants may be involved in CAD. In this study, VEGFR-1 gene promoter was genetically and functionally analyzed in large cohorts of AMI patients and ethnic-matched controls.

RESULTS

A total of 16 DNA sequence variants (DSVs) including six single-nucleotide polymorphisms (SNPs) were found in the VEGFR-1 gene promoter and 5'-untranslated region. Five novel DSVs and one SNP were only identified in AMI patients group. These DSVs and SNP significantly altered the transcriptional activity of the VEGFR-1 gene promoter in both HEK-293 and H9c2 cells (P < 0.05). Further electrophoretic mobility shift assay indicated that the DSVs and SNPs evidently affected the binding of transcription factors.

CONCLUSIONS

The genetic variants in VEGFR-1 gene identified in AMI patients may alter the transcriptional activity of the VEGFR-1 gene promoter and change VEGFR-1 level, contributing to AMI development.

Ardisia crispa root hexane fraction suppressed angiogenesis in human umbilical vein endothelial cells (HUVECs) and in vivo zebrafish embryo model

Ardisia crispa Thunb. A. DC. (Primulaceae) has been used extensively as folk-lore medicine in South East Asia including China and Japan to treat various inflammatory related diseases. Ardisia crispa root hexane fraction (ACRH) has been thoroughly studied by our group and it has been shown to exhibit anti-inflammatory, anti-hyperalgesic, anti-arthritic, anti-ulcer, chemoprevention and suppression against inflammation-induced angiogenesis in various animal model. Nevertheless, its effect against human endothelial cells in vitro has not been reported yet. Hence, the aim of the study is to investigate the potential antiangiogenic property of ACRH in human umbilical vein endothelial cells (HUVECs) and zebrafish embryo model. ACRH was separated from the crude ethanolic extract of the plant's root in prior to experimental studies. MTT assay revealed that ACRH exerted a concentration-dependent antiproliferative effect on HUVEC with the IC₅₀ of 2.49 ± 0.04 μg/mL. At higher concentration (10 μg/mL), apoptosis was induced without affecting the cell cycle distribution. Angiogenic properties including migration, invasion and differentiation of HUVECs, evaluated via wound healing, trans-well invasion and tube formation assay respectively, were significantly suppressed by ACRH in a concentration-dependent manner. Noteworthily, significant antiangiogenic effects were observed even at the lowest concentration used (0.1 μg/mL). Expression of proMMP-2, vascular endothelial growth factor (VEGF)-C, VEGF-D, Angiopoietin-2, fibroblast growth factor (FGF)-1, FGF-2, Follistatin, and hepatocyte growth factor (HGF) were significantly reduced in various degrees by ACRH. The ISV formation in zebrafish embryo was significantly suppressed by ACRH at the concentration of 5 μg/mL. These findings revealed the potential of ACRH as antiangiogenic agent by suppressing multiple proangiogenic proteins. Thus, it can be further verified via the transcription of these proteins from their respective DNA, in elucidating their exact pathways.

Study of pro-angiogenic activity of astilbin on human umbilical vein endothelial cells in vitro and zebrafish in vivo

Astilbin is a dihydroflavonol natural product isolated from a variety of food and medicinal herbs (e.g. Smilax glabra Roxb.), and its mechanism of action in vascular pharmacology remains unclear. The aim of this study was to investigate the pro-angiogenic effects of astilbin and its putative mechanism of action. Briefly, our in vitro studies showed a dose-dependent ability of astilbin to increase the ability of HUVECs to proliferate and migrate, and undergo cell invasion and tube formation. Moreover, astilbin significantly increased the expression levels of several major proteins involved in the angiogenesis pathway, e.g. PI3K, Akt, p38 and ERK1/2. Our in vivo studies demonstrated the ability of astilbin to significantly restore the blood vessel loss induced by VRI in a VRI-induced vascular insufficiency zebrafish model. In conclusion, in this study we first demonstrate that astilbin exhibits pro-angiogenic activity in HUVECs and VRI-induced vascular insufficient zebrafish, possibly through the activation of the PI3K/Akt and MAPK/ERK dependent signaling pathways. These findings suggest that astilbin could be further developed as a potential agent in the prevention or treatment of insufficient angiogenesis related diseases in the future.

Pro-angiogenic activity of astilbin on endothelial cells in vitro and zebrafish in vivo.

Ultrasound Evaluation of Anti-Vascular Endothelial Growth Factor-Induced Changes in Vascular Response Following Tendon Injury

While vascular ingrowth is necessary for tendon healing, hypervascularization following tendon injury is not always believed to be beneficial, and there is now evidence showing beneficial results of anti-angiogenic treatments in the context of tendon healing. However, the dose-dependency of anti-angiogenic-altered vascular response, as well as methods for evaluating these changes in vivo, has not been fully investigated. Therefore, the objective of this study was to evaluate if in vivo ultrasound imaging can detect dose-dependent, anti-angiogenic treatment-induced changes in vascularity in rat Achilles tendon after injury. Color Doppler ultrasound revealed an increase in vascularity in a low-dosage group, while photoacoustic imaging demonstrated a decrease in vascularity in mid- and high-dosage groups. Histologic staining supported the decrease in vascularity observed in the mid-dosage group. This study demonstrates dose-dependent vascular alterations from the delivery of an anti-angiogenic factor after tendon injury that can be detected through ultrasound imaging methods.

Vascular defects of DYRK1A knockouts are ameliorated by modulating calcium signaling in zebrafish

DYRK1A is a major causative gene in Down syndrome (DS). Reduced incidence of solid tumors such as neuroblastoma in DS patients and increased vascular anomalies in DS fetuses suggest a potential role of DYRK1A in angiogenic processes, but in vivo evidence is still scarce. Here, we used zebrafish dyrk1aa mutant embryos to understand DYRK1A function in cerebral vasculature formation. Zebrafish dyrk1aa mutants exhibited cerebral hemorrhage and defects in angiogenesis of central arteries in the developing hindbrain. Such phenotypes were rescued by wild-type dyrk1aa mRNA, but not by a kinase-dead form, indicating the importance of DYRK1A kinase activity. Chemical screening using a bioactive small molecule library identified a calcium chelator, EGTA, as one of the hits that most robustly rescued the hemorrhage. Vascular defects of mutants were also rescued by independent modulation of calcium signaling by FK506. Furthermore, the transcriptomic analyses supported the alterations of calcium signaling networks in dyrk1aa mutants. Together, our results suggest that DYRK1A plays an essential role in angiogenesis and in maintenance of the developing cerebral vasculature via regulation of calcium signaling, which may have therapeutic potential for DYRK1A-related vascular diseases.

Summary: The roles of DYRK1A in angiogenesis and maintenance of the developing cerebral vasculature mediated by calcium signaling were revealed using zebrafish dyrk1aa knockout mutants.

The roles and role-players in thyroid cancer angiogenesis

Thyroid cancer is the most prevalent endocrine cancer worldwide. Angiogenesis, the formation of new blood vessels, plays a pivotal role in the development and progression of tumors. Over the past years, cancer research has focused on the ability of tumors to induce newly formed blood vessel, because tumor growth and the process of cancer metastasis mainly depends on angiogenesis. Tumor neovascularization occurs following the imbalance between pro-angiogenic and anti-angiogenic factors until the tumor switches to an angiogenic phenotype. A number of signaling factors and receptors that are implicated in the regulation of angiogenesis have been identified and characterized; most notably, the vascular endothelial growth factors (VEGFs) family and their receptors, which are the main pro-angiogenic molecules during early development and in pathological conditions such as cancer. Although thyroid is a highly vascularized organ, angiogenic switch in tumors of this organ leads to the formation of a vast network of blood vessels that favors the dissemination of tumor cells to distant organs and results in deterioration of patient conditions. Accordingly, the identification of key angiogenic biomarkers for thyroid cancer can facilitate diagnosis, prognosis and clinical decision-making and also may help to discover targeting factors for effective cancer therapy as well as monitoring response to therapy. Hence, the main purposes of this review are to summarize the types and mechanisms of angiogenesis emphasizing the prominent factors implicated in thyroid cancer angiogenesis.

Healing potential of injectable Aloe vera hydrogel loaded by adipose-derived stem cell in skin tissue-engineering in a rat burn wound model

Adipose stem cells (ASCs) are a great promise in wound healing due to their potential in differentiating into various cell lineages and secreting growth factors. The purpose of this study is to evaluate the in vivo effects of Aloe vera hydrogel loaded by allogeneic ASCs on a rat burn wound model. The ASCs were isolated, cultured and mixed with 50% Aloe vera hydrogel and injected intradermally around the wound. Demineralized bone matrix (DBM) was used as dressing in the experiment. The burn wound-healing properties of different experimental groups were investigated by histopathological, molecular, scanning electron microscopic and biochemical analysis at the 7th, 14th and 28th days post-wounding. The Aloe vera and DBM-Aloe vera groups showed almost similar healing properties, while treatment by DBM-Aloe vera/ASCs significantly enhanced wound healing. The levels of transforming growth factor-β1 (TGF-β1) and interleukin-1β markedly decreased at the 7th day post-injury, in the DBM-Aloe vera/ASC-treated group, suggesting that this treatment regime subsided the inflammatory responses. Angiogenesis, re-epithelialization and the level of TGF-β1 in the wounds treated with DBM-Aloe vera/ASCs were also remarkably higher than those of other groups, at the 14th day post-injury. Besides, scar formation significantly decreased in the DBM-Aloe vera/ASC-treated wounds when compared with other groups. Our biochemical results were in agreement with the molecular and histopathological findings and strongly demonstrated that a DBM-Aloe vera/ASC composite can stimulate burn wound healing. These results suggest that the DBM-Aloe vera/ASC composite can be considered as a promising therapeutic strategy in the treatment of burn wounds.

Enhancing bioactivity, physicochemical, and pharmacokinetic properties of a nano-sized, anti-VEGFR2 Adnectin, through PASylation technology

The crucial role of VEGF receptor 2 (VEGFR2) signaling in the angiogenesis and metastasis of solid tumors has prompted the development of inhibitors with minimal bystander effects. Recently, Adnectin C has attracted attention for cancer treatment. To overcome the problematic properties of Adnectin, a novel form of Adnectin C has been designed by its fusion to a biodegradable polymeric peptide containing Pro/Ala/Ser (PAS) repetitive residues. E. coli-expressed recombinant fused and unfused proteins were compared in terms of bioactivity, physicochemical, and pharmacokinetic properties using standard methods. Dynamic light scattering (DLS) analysis of PASylated adnectin C revealed an approximate 2-fold increase in particle size with a slight change in the net charge. Additionally, fusion of the PAS sequence improved its stability against the growth of thermo-induced aggregated forms. The high receptor-binding and improved binding kinetic parameters of PASylated Adnectin C was confirmed by ELISA and surface plasmon resonance assays, respectively. Pharmacokinetic studies showed a noticeable increase in the terminal half-life of Adnectin C-PAS#1(200) by a factor of 4.57 after single dose by intravenous injection into female BALB/c mice. The results suggest that PASylation could offer a superior delivery strategy for developing Adnectin-derived drugs with improved patient compliance.

Preoperative Timing of Intravitreal Bevacizumab Injection for Proliferative Diabetic Retinopathy Patients

OBJECTIVE

To evaluate the changes in aqueous concentrations of inflammatory cytokines and fibrosis-related factors, and to detect the expression of vascular endothelial growth factor (VEGF) and proliferating cells in fibrovascular membranes (FVMs) of patients with proliferative diabetic retinopathy (PDR) after injection of intravitreal bevacizumab (IVB).

METHODS

Forty-two eyes of 42 patients with PDR, including 28 eyes that received IVB (1.25 mg) 2, 5, and 14 days before pars plana vitrectomy (PPV), and 14 eyes without IVB, were enrolled, in addition to 10 eyes of 10 patients with nondiabetic ocular diseases. Aqueous concentrations of inflammatory cytokines and fibrosis-related factors were analyzed by a multiplex bead assay. Fluorescence immunostaining was performed to examine the expression of VEGF and proliferating cells in the excised epiretinal membranes.

RESULTS

PDR eyes without IVB had the highest vitreous VEGF levels, and the level was statistically significant compared with that of PDR eyes that received IVB 2 days before surgery, PDR eyes that received IVB 5 days before surgery, and nondiabetic eyes (p = 0.011, p = 0.012, and p < 0.001, respectively). The expression of fibroblastic cells and connective tissue growth factor increased in epiretinal FVMs of the IVB group 21 days after treatment.

CONCLUSIONS

IVB injection may lead to a decrease in the intraocular concentrations of VEGF after 2-5 days and induce the formation of proliferation after 21 days, which suggests that PPV in PDR patients should take place within 1 week of the administration of preoperative IVB.

Diphlorethohydroxycarmalol Isolated from Ishige okamurae Represses High Glucose-Induced Angiogenesis In Vitro and In Vivo

Diabetes mellitus causes abnormalities of angiogenesis leading to vascular dysfunction and serious pathologies. Diphlorethohydroxycarmalol (DPHC), which is isolated from Ishige okamurae, is well known for its bioactivities, including antihyperglycemic and protective functions against diabetes-related pathologies. In the present study, the inhibitory effect of DPHC on high glucose-induced angiogenesis was investigated on the human vascular endothelial cell line EA.hy926. DPHC inhibited the cell proliferation, cell migration, and tube formation in cells exposed to 30 mM of glucose to induce angiogenesis. Furthermore, the effect of DPHC against high glucose-induced angiogenesis was evaluated in zebrafish embryos. The treatment of embryos with DPHC suppressed high glucose-induced dilation in the retinal vessel diameter and vessel formation. Moreover, DPHC could inhibit high glucose-induced vascular endothelial growth factor receptor 2 (VEGFR-2) expression and its downstream signaling cascade. Overall, these findings suggest that DPHC is actively involved in the suppression of high glucose-induced angiogenesis. Hence, DPHC is a potential agent for the development of therapeutics against angiogenesis induced by diabetes.

Effects of auriculasin on vascular endothelial growth factor (VEGF)-induced angiogenesis via regulation of VEGF receptor 2 signaling pathways in vitro and in vivo

Angiogenesis plays an important role in various pathological conditions such as cancer via excessive delivery of oxygen and nutrients. Recent studies have demonstrated that understanding the molecular basis of natural agents in angiogenesis is critical for the development of promising cancer therapeutics. In this study, auriculasin, an active component from Flemingia philippinensis, was found to exert strong anti-angiogenesis activity. Treatment with auriculasin suppressed proliferation of human umbilical vein endothelial cells (HUVECs) by modulating expression of Bcl-2, Bcl-_XL, and vascular endothelial growth factor (VEGF). Further, auriculasin inhibited VEGF-induced chemotactic migration, invasion, and capillary-like structure formation of endothelial cells. In addition, auriculasin abrogated VEGF-induced vascular network formation around rat aortic rings as well as blocked accumulation of hemoglobin, endothelial cells and VEGF in the Matrigel plug of C57BL/6 mice. The inhibitory effect of auriculasin on angiogenesis was well correlated with inhibition of VEGF receptor 2 (VEGFR2) activation as well as phosphorylation of intracellular downstream protein kinases of VEGFR2 containing Akt, mammalian target of rapamycin (mTOR), phosphoinositide 3-kinase (PI3K), p-38, extracellular signal-related kinase (ERK), and Src. Taken together, this study reports that auriculasin potently inhibits angiogenesis by modulating VEGFR2-related signaling pathways, which further validates its great potential in clinical applications.

Targeting the Tie2-αvβ3 integrin axis with bi-specific reagents for the inhibition of angiogenesis

BACKGROUND

Increased activity of the receptor tyrosine kinase Tie2 has been implicated in the promotion of pathological angiogenesis. This activity is mainly mediated through angiopoietin (Ang)1- and Ang2-dependent activation of integrins by Tie2, rendering the Ang/Tie2/integrin axis an attractive putative target for cancer therapeutics.

RESULTS

To target this axis, we developed single domain, non-immunoglobulin high-affinity bi-specific protein inhibitors against both Tie2 and αvβ3 integrin. We have previously engineered the Ang2-binding domain of Tie2 (Ang2-BD) as a Tie2 inhibitor. Here, we engineered an exposed loop in Ang2-BD to generate variants that include an integrin-binding Arg-Gly-Asp (RGD) motif and used flow cytometry screening of a yeast-displayed Ang2-BD RGD loop library to identify the integrin antagonists. The bi-specific antagonists targeting both Tie2 and αvβ3 integrin inhibited adhesion and proliferation of endothelial cells cultured together with the αvβ3 integrin ligand vitronectin, as well as endothelial cell invasion and tube formation. The bi-specific reagents inhibited downstream signaling by Tie2 intracellularly in response to its agonist Ang1 more effectively than the wild-type Ang2 BD that binds Tie2 alone.

CONCLUSIONS

Collectively, this study-the first to describe inhibitors targeting all the known functions resulting from Tie2/integrin αvβ3 cross-talk-has created new tools for studying Tie2- and integrin αvβ3-dependent molecular pathways and provides the basis for the rational and combinatorial engineering of ligand-Tie2 and ligand-integrin αvβ3 receptor interactions. Given the roles of these pathways in cancer angiogenesis and metastasis, this proof of principle study paves the route to create novel Tie2/integrin αvβ3-targeting proteins for clinical use as imaging and therapeutic agents.

Rutacecarpine Inhibits Angiogenesis by Targeting the VEGFR2 and VEGFR2-Mediated Akt/mTOR/p70s6k Signaling Pathway

This study aimed to investigate the effect of Ru (Rut) on angiogenesis, and the underlying regulation mechanism of signal transduction. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, adhesion inhibition experiment, migration inhibition experiment, and chick embryo chorioallantoic membrane (CAM) assays were performed on models of angiogenesis. The potential targets of rutaecarpine (Ru) were reverse screened with Discovery Studio 2017. The interaction between the compound and target were detected by surface plasmon resonance (SPR), enzyme-activity experiment, and Western blot assay. The obtained results confirmed that Ru exhibited modest inhibitory activity against human umbilical vein endothelial cells (HUVECs) (IC₅₀ =16.54 ± 2.4 μM) and remarkable inhibitive effect against the migration and adhesion of HUVECs, as well as significant anti-angiogenesis activities in the CAM assay. The possible targets of vascular endothelial growth factor receptor 2 (VEGFR2) were identified by computer-aided simulation. Results showed a good binding relationship between the ligand and target through molecular docking, and this relationship was confirmed by SPR analysis. Furthermore, enzyme-activity experiment and western blot assay showed that Ru remarkably inhibited the activity of VEGFR2 and blocked the VEGFR2-mediated Akt/ (mTOR)/p70s6k signaling pathway in vitro. Ru can be a potential drug candidate for cancer prevention and cancer therapy.