Inhibition of VEGF-Induced VEGFR-2 Activation and HUVEC Migration by Melatonin and Other Bioactive Indolic Compounds

Endothelial cells-derived exosomes-based hydrogel improved tendinous repair via anti-inflammatory and tissue regeneration-promoting properties

Tendon injuries are common orthopedic ailments with a challenging healing trajectory, especially in cases like the Achilles tendon afflictions. The healing trajectory of tendon injuries is often suboptimal, leading to scar formation and functional impairment due to the inherent low metabolic activity and vascularization of tendon tissue. As pressing is needed for effective interventions, efforts are made to explore biomaterials to augment tendon healing. However, tissue engineering approaches face hurdles in optimizing tissue scaffolds and nanomedical strategies. To navigate these challenges, an injectable hydrogel amalgamated with human umbilical vein endothelial cells-derived exosomes (HUVECs-Exos) was prepared and named H-Exos-gel in this study, aiming to enhance tendon repair. In our research involving a model of Achilles tendon injuries in 60 rats, we investigated the efficacy of H-Exos-gel through histological assessments performed at 2 and 4 weeks and behavioral assessments conducted at the 4-week mark revealed its ability to enhance the Achilles tendon's mechanical strength, regulate inflammation and facilitate tendon regeneration and functional recovery. Mechanically, the H-Exos-gel modulated the cellular behaviors of macrophages and tendon-derived stem cells (TDSCs) by inhibiting inflammation-related pathways and promoting proliferation-related pathways. Our findings delineate that the H-Exos-gel epitomizes a viable bioactive medium for tendon healing, heralding a promising avenue for the clinical amelioration of tendon injuries.

An essential role for EROS in redox-dependent endothelial signal transduction

The chaperone protein EROS ("Essential for Reactive Oxygen Species") was recently discovered in phagocytes. EROS was shown to regulate the abundance of the ROS-producing enzyme NADPH oxidase isoform 2 (NOX2) and to control ROS-mediated cell killing. Reactive oxygen species are important not only in immune surveillance, but also modulate physiological signaling responses in multiple tissues. The roles of EROS have not been previously explored in the context of oxidant-modulated cell signaling. Here we show that EROS plays a key role in ROS-dependent signal transduction in vascular endothelial cells. We used siRNA-mediated knockdown and developed CRISPR/Cas9 knockout of EROS in human umbilical vein endothelial cells (HUVEC), both of which cause a significant decrease in the abundance of NOX2 protein, associated with a marked decrease in RAC1, a small G protein that activates NOX2. Loss of EROS also attenuates receptor-mediated hydrogen peroxide (H2O2) and Ca2+ signaling, disrupts cytoskeleton organization, decreases cell migration, and promotes cellular senescence. EROS knockdown blocks agonist-modulated eNOS phosphorylation and nitric oxide (NO●) generation. These effects of EROS knockdown are strikingly similar to the alterations in endothelial cell responses that we previously observed following RAC1 knockdown. Proteomic analyses following EROS or RAC1 knockdown in endothelial cells showed that reduced abundance of these two distinct proteins led to largely overlapping effects on endothelial biological processes, including oxidoreductase, protein phosphorylation, and endothelial nitric oxide synthase (eNOS) pathways. These studies demonstrate that EROS plays a central role in oxidant-modulated endothelial cell signaling by modulating NOX2 and RAC1.

A consortium of different Saccharomyces species enhances the content of bioactive tryptophan-derived compounds in wine fermentations

In recent years, the presence of molecules derived from aromatic amino acids in wines has been increasingly demonstrated to have a significant influence on wine quality and stability. In addition, interactions between different yeast species have been observed to influence these final properties. In this study, a screening of 81 yeast strains from different environments was carried out to establish a consortium that would promote the improvement of indolic compound levels in wine. Two strains, Saccharomyces uvarum and Saccharomyces eubayanus, with robust fermentative capacity were selected to be combined with a Saccharomyces cerevisiae strain with a predisposition towards the production of indolic compounds. Fermentation dynamics were studied in pure cultures, co-inoculations and sequential inoculations, analysing strain interactions and end-of-fermentation characteristics. Fermentations showing significant interactions were further analyzed for the resulting indolic compounds and aroma profile, with the aim of observing potential interactions and synergies resulting from the combination of different strains in the final wine. Sequential inoculation of S. cerevisiae after S. uvarum or S. eubayanus was observed to increase indolic compound levels, particularly serotonin and 3-indoleacetic acid. This study is the first to demonstrate how the formation of microbial consortia can serve as a useful strategy to enhance compounds with interesting properties in wine, paving the way for future studies and combinations.

Evaluation of serum pro/anti-angiogenic biomarkers in hyperglycemic rats treated with Securigera securidaca seeds, alone and in combination with Glibenclamide

Introduction

Herbal medicines are commonly used by many people with diabetes in addition to standard treatment. Plants contain numerous known and unknown compounds that may exacerbate or ameliorate diabetes complications. Therefore, it is crucial to be aware of the side effects of these herbs before prescribing them. This study aimed to investigate the effects of hydroalcoholic extracts of Securigera securidaca (HESS) seeds alone and in combination with glibenclamide on the angiogenic/anti-angiogenic balance in streptozotocin (STZ)-induced diabetic rats.

Methods

Groups involved in this animal study included diabetic and healthy controls, three doses of HESS, glibenclamide, and combination therapy. Serum samples were collected and analyzed for a vascular endothelial growth factor (VEGF), fibroblast growth factor 21 (FGF21), fetal liver kinase 1 (FLK-1), soluble fms-like tyrosine kinase 1 (sFLT-1), and transforming growth factor -beta (TGF-β).

Results

Induction of diabetes increased VEGF, FGF21, and TGF-β serum levels and decreased circulating FLK-1 and sFLT-1 factors. Herbal extract, except TGF-β, had little effect on the above blood levels even at the highest doses. Glibenclamide was more effective than the highest dose of HESS in improving the vascular complications of diabetes. Combination therapy with the highest dose of HESS partly enhanced the glibenclamide effects.

Conclusion

Compared with glibenclamide as a standard chemical drug, HESS had no significant effects on the blood levels of the pro/anti-angiogenesis factor in diabetic rats. Glibenclamide attenuated the levels of the biomarkers and its effects were somewhat enhanced in combination with the highest dose of HESS.

Topical Application of Cell-Penetrating Peptide Modified Anti-VEGF Drug Alleviated Choroidal Neovascularization in Mice

Background

Age-related macular degeneration (AMD) stands as the foremost cause of irreversible central vision impairment, marked by choroidal neovascularization (CNV). The prevailing clinical approach to AMD treatment relies on intravitreal injections of anti-vascular endothelial growth factor (VEGF) drugs. However, this method is encumbered by diverse complications, prompting exploration of non-invasive alternatives such as ocular administration via eye drops for anti-VEGF therapy.

Methods

Two complexes, 5-FITC-CPP-Ranibizumab (5-FCR) and 5-FITC-CPP-Conbercept (5-FCC), were synthesized by incorporating the anti-VEGF drugs Ranibizumab (RBZ) or Conbercept (CBC) with cell-penetrating peptide (CPP). Circular dichroism spectrum (CD) facilitated complexes characterization. Eye drops was utilized to address laser-induced CNV in mice. Fluorescein fundus angiography (FFA) observe the CNV lesion, while FITC-dextran and IB4 dual fluorescent staining, along with hematoxylin-eosin (HE) staining, assessed in lesion size. Tissue immunofluorescence examined CD31 and VEGF expression in choroidal/retinal pigment epithelial (RPE) tissues. Biocompatibility and biosafety of 5-FCR and 5-FCC was evaluated through histological examination of various organs or cell experiments.

Results

Both 5-FCR and 5-FCC exhibited favorable biocompatibility and safety profiles. VEGF-induced migration of Human umbilical vein endothelial cells (HUVECs) significantly decreased post-5-FCR/5-FCC treatment. Additionally, both complexes suppressed VEGF-induced tube formation in HUVECs. FFA results revealed a significant improvement in retinal exudation in mice. Histological examination unveiled the lesion areas in the 5-FCR and 5-FCC groups showed a significant reduction compared to the control group. Similar outcomes were observed in histological sections of the RPE-choroid-sclera flat mounts.

Conclusion

In this study, utilizing the properties of CPP and two anti-VEGF drugs, we successfully synthesized two complexes, 5-FCR and 5-FCC, through a straightforward approach. Effectively delivering the anti-VEGF drugs to the target area in a non-invasive manner, suppressing the progression of laser-induced CNV. This offers a novel approach for the treatment of wet AMD.

Angiogenesis, coagulation, and fibrinolytic markers in acute promyelocytic leukemia (NB4): An evaluation of melatonin effects

Melatonin is a powerful biological agent that has been shown to inhibit angiogenesis and also exerts anti-inflammatory effects. It is well known that new blood vessel formation (angiogenesis) has become an urgent issue in leukemia as well as solid tumors. Acute promyelocytic leukemia (APL) is a form of liquid cancer that manifests increased angiogenesis in the bone marrow of patients. Despite high-rate curable treatment with all-trans-retinoic acid (ATRA) and recently arsenic-trioxide (ATO), early death because of hemorrhage, coagulopathy, and Disseminated intravascular coagulation (DIC) remains still a concerning issue in these patients. It is, therefore, urgent to seek treatment strategies with antiangiogenic capabilities that also diminish coagulopathy and hyperfibrinolysis in APL patients. In this study, a coculture system with human umbilical vein endothelial cells (HUVECs) and NB4 APL cells was used to investigate the direct effect of melatonin on angiogenesis and its possible action on tissue factor (TF) and tissue-type plasminogen activator-1 (TPA-1) expression. Our experiments revealed that HUVEC-induced angiogenesis by cocultured NB4 cells was suppressed when melatonin alone or in combination with ATRA was added to the incubation medium. Melatonin at concentrations of 1 mM inhibited tube formation of HUVECs and also decreased interleukin-6 secretion and VEGF mRNA expression in HUVEC and NB4 cells. Taken together, the results of this study demonstrate that melatonin inhibits accelerated angiogenesis of HUVECs and ameliorates the coagulation and fibrinolysis indices stimulated by coculturing with NB4 cells.

Effect of whole foods on the microbial production of tryptophan-derived aryl hydrocarbon receptor agonists in growing pigs

Effects of whole foods on the microbial production of tryptophan-derived aryl hydrocarbon receptor (AhR) ligands in the intestine were investigated in a pig model. Ileal digesta and faeces of pigs after feeding of eighteen different foods were analyzed. Indole, indole-3-propionic acid, indole-3-acetic acid, indole-3-lactic acid, kynurenine, tryptamine, and indole-3-aldehyde were identified in ileal digesta, which were also identified in faeces but at higher concentrations except indole-3-lactic acid, together with skatole, oxindole, serotonin, and indoleacrylic acid. The panel of tryptophan catabolites in ileal digesta and faeces varied across different foods. Eggs induced the highest overall concentration of catabolites in ileal digesta dominated by indole. Amaranth induced the highest overall concentration of catabolites in faeces dominated by skatole. Using a reporter cell line, we observed many faecal samples but not ileal samples retained AhR activity. Collectively, these findings contribute to food selection targeting AhR ligands production from dietary tryptophan in the intestine.

Complement factor H inhibits endothelial cell migration through suppression of STAT3 signaling

Complement factor H (CFH), a major soluble inhibitor of complement, is a plasma protein that directly interacts with the endothelium of blood vessels. Mutations in the CFH gene lead to diseases associated with excessive angiogenesis; however, the underlying mechanisms are unknown. The present study aimed to determine the effects of CFH on endothelial cells and to explore the underlying mechanisms. The adenoviral plasmid expressing CFH was transduced into HepG2 cells, and the culture medium supernatant was collected and co-cultured with human umbilical vein endothelial cells (HUVECs). Cell proliferation was measured by CCK8 and MTT assays, and cell migration was measured by wound healing and Transwell assays. Reverse transcription-quantitative PCR was performed to detect gene transcription. Western blotting was used to determine protein levels. The results revealed that CFH can inhibit migration, but not viability, of HUVECs. In addition, CFH did not significantly alter MAPK or TGF-β signaling, whereas it decreased STAT3 phosphorylation in HUVECs. Furthermore, CFH failed to reduce migration of HUVECs, with inhibition of STAT3 signaling by STATTIC or activation of STAT3 signaling by overexpression of STAT3 (Y705D) compromising CFH-inhibited HUVEC migration. CFH also decreased the expression levels of vascular endothelial growth factor receptor 2, a downstream effector of STAT3 mediating endothelial cell migration. In conclusion, the present study suggested that CFH may be a potential therapeutic target for angiogenesis-related diseases.

Melatonin in Endometriosis: Mechanistic Understanding and Clinical Insight

Endometriosis is defined as the development of endometrial glands and stroma outside the uterine cavity. Pathophysiology of this disease includes abnormal hormone profiles, cell survival, migration, invasion, angiogenesis, oxidative stress, immunology, and inflammation. Melatonin is a neuroendocrine hormone that is synthesized and released primarily at night from the mammalian pineal gland. Increasing evidence has revealed that melatonin can be synthesized and secreted from multiple extra-pineal tissues where it regulates immune response, inflammation, and angiogenesis locally. Melatonin receptors are expressed in the uterus, and the therapeutic effects of melatonin on endometriosis and other reproductive disorders have been reported. In this review, key information related to the metabolism of melatonin and its biological effects is summarized. Furthermore, the latest in vitro and in vivo findings are highlighted to evaluate the pleiotropic functions of melatonin, as well as to summarize its physiological and pathological effects and treatment potential in endometriosis. Moreover, the pharmacological and therapeutic benefits derived from the administration of exogenous melatonin on reproductive system-related disease are discussed to support the potential of melatonin supplements toward the development of endometriosis. More clinical trials are needed to confirm its therapeutic effects and safety.

Evidence for the Benefits of Melatonin in Cardiovascular Disease

The pineal gland is a neuroendocrine gland which produces melatonin, a neuroendocrine hormone with critical physiological roles in the circadian rhythm and sleep-wake cycle. Melatonin has been shown to possess anti-oxidant activity and neuroprotective properties. Numerous studies have shown that melatonin has significant functions in cardiovascular disease, and may have anti-aging properties. The ability of melatonin to decrease primary hypertension needs to be more extensively evaluated. Melatonin has shown significant benefits in reducing cardiac pathology, and preventing the death of cardiac muscle in response to ischemia-reperfusion in rodent species. Moreover, melatonin may also prevent the hypertrophy of the heart muscle under some circumstances, which in turn would lessen the development of heart failure. Several currently used conventional drugs show cardiotoxicity as an adverse effect. Recent rodent studies have shown that melatonin acts as an anti-oxidant and is effective in suppressing heart damage mediated by pharmacologic drugs. Therefore, melatonin has been shown to have cardioprotective activity in multiple animal and human studies. Herein, we summarize the most established benefits of melatonin in the cardiovascular system with a focus on the molecular mechanisms of action.

Molecular and cellular mechanisms of melatonin in breast cancer

Breast cancer is considered as one of the most important health problems due to its poor prognosis and high rate of mortality and new diagnosed cases. Annually, a great number of deaths are reported in men and women; this means that despite all the improvements in cancer diagnosis and treatment, still, an intense need for more effective approaches exists. Melatonin is a multivalent compound which has a hand in several cellular and molecular processes and therefore, is an appropriate candidate for treatment of many diseases like cancer. Currently, considerable properties of this agent have oriented the research towards investigating its effects specifically in breast cancer. In this review, we gathered a bunch of evidence in order to give a new sight for breast cancer treatment utilizing melatonin. We expect that in coming years, melatonin will become one of the most common therapeutic drugs with lesser side-effects than other chemotherapeutic drugs.

Neutrophil-like cell membrane-coated siRNA of lncRNA AABR07017145.1 therapy for cardiac hypertrophy via inhibiting ferroptosis of CMECs

Cardiac microvascular dysfunction is associated with cardiac hypertrophy and can eventually lead to heart failure. Dysregulation of long non-coding RNAs (lncRNAs) has recently been recognized as one of the key mechanisms involved in cardiac hypertrophy. However, the potential roles and underlying mechanisms of lncRNAs in cardiac microvascular dysfunction have not been explicitly delineated. Our results confirmed that cardiac microvascular dysfunction was related to cardiac hypertrophy and ferroptosis of cardiac microvascular endothelial cells (CMECs) occurred during cardiac hypertrophy. Using a combination of in vivo and in vitro studies, we identified a lncRNA AABR07017145.1, named as lncRNA AAB for short, and revealed that lncRNA AAB was upregulated in the hearts of cardiac hypertrophy rats as well as in the Ang II-induced CMECs. Importantly, we found that lncRNA AAB sponged and sequestered miR-30b-5p to induce the imbalance of MMP9/TIMP1, which enhanced the activation of transferrin receptor 1 (TFR-1) and then eventually led to the ferroptosis of CMECs. Moreover, we have developed a delivery system based on neutrophil membrane (NM)-camouflaged mesoporous silica nanocomplex (MSN) for inhibition of cardiac hypertrophy, indicating the potential role of silenced lncRNA AAB (si-AAB) and overexpressed miR-30b-5p as the novel therapy for cardiac hypertrophy.

A Nanocoating Co-Localizing Nitric Oxide and Growth Factor onto Individual Endothelial Cells Reveals Synergistic Effects on Angiogenesis

The delivery of nitric oxide (NO)-an intrinsic cellular signaling molecule-is promising for disease treatment, in particular to vascular diseases, due to its endothelial-derived inherent nature. The limited diffusion distance of labile NO prompts researchers to develop various carriers and targeting methods for specific sites. In contrast to the apoptotic effect of NO, such as anticancer, delivering low NO concentration at the desired targeting area is still intricate in a physiological environment. In this study, the layer-by-layer assembled nanocoating is leveraged to develop a direct NO delivery platform to individual endothelial cells (ECs). NO can be localized to individual ECs via S-nitrosothiol-bound polyacrylic acid which is a polymer directly providing an endothelial-like constant level of NO. To increase angiogenic activation along with NO, VEGF is additionally applied to specific receptors on the cell surface. Notably, the survival and proliferation of ECs are significantly increased by a synergistic effect of NO and VEGF co-localized via nanocoating. Furthermore, the nanocoating remarkably promoted cell migration and tubule formation-prerequisites of angiogenesis. The proposed unique technology based on nanocoating demonstrates great potential for conferring desired angiogenic functions to individual ECs through efficient NO delivery.

Anti-VEGF Effect of Bioactive Indolic Compounds and Hydroxytyrosol Metabolites

Angiogenesis is a key process involved in both cancer and cardiovascular diseases, the vascular endothelial growth factor (VEGF) and its VEGF receptor-2 (VEGFR-2) being the main triggers. The aim of this study was to determine the molecular mechanism underlying the potent inhibition of VEGF signaling by hydroxytyrosol (HT) metabolites and indolic compounds and establish a relation between their structure and bioactivity. Experiments involved the evaluation of their potential to inhibit VEGF on human umbilical vein endothelial cells (HUVECs) by ELISA assay and their subsequent effect on the downstream signaling pathway (PLCγ1, Akt, and endothelial nitric oxide synthetase (eNOS)) by Western blot. Respectively, 3,4-dihydroxyphenylacetaldehyde (DOPAL) (100 µM) and indole pyruvic acid (IPy) (1 mM) were capable of inhibiting VEGFR-2 activation with an IC50 value of 119 µM and 1.037 mM. The anti-angiogenic effect of DOPAL and IPy is mediated via PLCγ1. Additionally, DOPAL significantly increases eNOS phosphorylation, while IPy maintained it. These data provide for the first time evidence of the anti-angiogenic effect of DOPAL and IPy for future use as potential bioactive food ingredients.

Melatonin prevents cyclophosphamide-induced primordial follicle loss by inhibiting ovarian granulosa cell apoptosis and maintaining AMH expression

Cyclophosphaty -45mide (Cyc) chemotherapy in young female cancer patients is associated with an increased risk of premature ovarian insufficiency (POI). This study was designed to investigate the protective role of melatonin (Mel) as an adjuvant against Cyc-induced POI. Female mice received a single intraperitoneal (i.p.) dose of Cyc (75 mg/kg). Mel protection was achieved in mice after i.p. injection of melatonin (50 mg/kg) every 24 h for four consecutive days prior to chemotherapy initiation and for 14 additional days. Ovarian reserve testing, hormonal assays for follicle-stimulating hormone, luteinizing hormone, and anti-Müllerian hormone (AMH), assessment of the oxidative stress status, and measurement of the relative expression of genes in PTEN/AKT/FOXO3a and mitochondrial apoptosis pathways were performed. The results showed that treatment with 50 mg/kg Mel significantly prevented Cyc-induced over-activation of primordial follicles by maintaining the plasma level of AMH and subsequently preventing litter size reduction in mice treated with Cyc chemotherapy. Importantly, Mel treatment significantly prevented ovarian granulosa cell loss by inhibiting the mitochondrial apoptotic pathway. Identifying the protective actions of Mel against Cyc-induced primordial follicle loss has important implications for fertility maintenance in young cancer patients undergoing chemotherapy.

Mechanism Analysis of Antiangiogenic d-Isofloridoside from Marine Edible Red algae Laurencia undulata in HUVEC and HT1080 cell

Laurencia undulata, as one of the most biologically active species in the genus Laurencia, is an edible folk herb red algae. Among them, d-isofloridoside (DIF, 940.68 Da) is isolated from Laurencia undulata, which has antioxidant and matrix metalloproteinases (MMP) inhibitory activities. However, its mechanism of action on tumor angiogenesis has not yet been reported. In this study, we have studied the mechanism of DIF on tumor metastasis and angiogenesis in HT1080 cell and human vascular endothelial cell (HUVEC). The results show that DIF can reduce the activity of MMP-2/9, and can inhibit the expression of hypoxia-inducible factor-1α (HIF-1α) by regulating the downstream PI3K/AKT and mitogen-activated protein kinases (MAPK) pathways, thereby down-regulating the production of vascular endothelial growth factor (VEGF) in CoCl₂-induced HT1080 cell. In addition, DIF can inhibit the activation of VEGF receptor (VEGFR-2), regulate downstream PI3K/AKT, MAPK, nuclear factor-kappa B (NF-κB) signal pathways, activate apoptosis, and thus down-regulate the production of platelet-derived growth factor (PDGF) in VEGF-induced HUVEC. In conclusion, our research shows that DIF has the potential to develop into a tumor-preventing functional food and tumor angiogenesis inhibitor, and it can provide theoretical guidance for the high-value comprehensive utilization of edible red algae Laurencia undulata.

Melatonin prevents blood-retinal barrier breakdown and mitochondrial dysfunction in high glucose and hypoxia-induced in vitro diabetic macular edema model

Diabetic macular edema (DME) is a leading cause of blindness in diabetic retinopathy. Prolonged hyperglycemia plus hypoxia contributes to DME pathogenesis. Retinal pigmented epithelial cells comprise the outer blood-retinal barrier and are essential for maintaining physiological functioning of the retina. Melatonin acts as an antioxidant and regulator of mitochondrial bioenergetics and has a protective effect against ocular diseases. However, the role of mitochondrial dysfunction and the therapeutic potential of melatonin in DME remain largely unexplored. Here, we used an in vitro model of DME to investigate blood-retinal barrier integrity and permeability, angiogenesis, mitochondrial dynamics, and apoptosis signaling to evaluate the potential protective efficacy of melatonin in DME. We found that melatonin prevents cell hyper-permeability and outer barrier breakdown by reducing HIF-1α, HIF-1β and VEGF and VEGF receptor gene expression. In addition, melatonin reduced the expression of genes involved in mitochondrial fission (DRP1, hFis1, MIEF2, MFF), mitophagy (PINK, BNip3, NIX), and increased the expression of genes involved in mitochondrial biogenesis (PGC-1α, NRF2, PPAR-γ) to maintain mitochondrial homeostasis. Moreover, melatonin prevented apoptosis of retinal pigmented epithelial cells. Our results suggest that mitochondrial dysfunction may be involved in DME pathology, and melatonin may have therapeutic value in DME, by targeting signaling in mitochondria.

Role and Therapeutic Potential of Melatonin in Various Type of Cancers

Cancer is a large group of diseases and the second leading cause of death worldwide. Lung, prostate, colorectal, stomach, and liver cancers are the most common types of cancer in men, whereas breast, colorectal, lung, cervical, and thyroid cancers are the most common among women. Presently, various treatment strategies, including surgical resection combined with chemotherapy, radiotherapy, nanotherapy, and immunotherapy, have been used as conventional treatments for patients with cancer. However, the clinical outcomes of advanced-stage disease remain relatively unfavorable owing to the emergence of chemoresistance, toxicity, and other undesired detrimental side effects. Therefore, new therapies to overcome these limitations are indispensable. Recently, there has been considerable evidence from experimental and clinical studies suggesting that melatonin can be used to prevent and treat cancer. Studies have confirmed that melatonin mitigates the pathogenesis of cancer by directly affecting carcinogenesis and indirectly disrupting the circadian cycle. Melatonin (MLT) is nontoxic and exhibits a range of beneficial effects against cancer via apoptotic, antiangiogenic, antiproliferative, and metastasis-inhibitory pathways. The combination of melatonin with conventional drugs improves the drug sensitivity of cancers, including solid and liquid tumors. In this manuscript, we will comprehensively review some of the cellular, animal, and human studies from the literature that provide evidence that melatonin has oncostatic and anticancer properties. Further, this comprehensive review compiles the available experimental and clinical data analyzing the history, epidemiology, risk factors, therapeutic effect, clinical significance, of melatonin alone or in combination with chemotherapeutic agents or radiotherapy, as well as the underlying molecular mechanisms of its anticancer effect against lung, breast, prostate, colorectal, skin, liver, cervical, and ovarian cancers. Nonetheless, in the interest of readership clarity and ease of reading, we have discussed the overall mechanism of the anticancer activity of melatonin against different types of cancer. We have ended this report with general conclusions and future perspectives.

Therapeutic targets of cancer drugs: Modulation by melatonin

The biological functions of melatonin range beyond the regulation of the circadian rhythm. With regard to cancer, melatonin's potential to suppress cancer initiation, progression, angiogenesis and metastasis as well as sensitizing malignant cells to conventional chemo- and radiotherapy are among its most interesting effects. The targets at which melatonin initiates its anti-cancer effects are in common with those of a majority of existing anti-cancer agents, giving rise to the notion that this molecule is a pleiotropic agent sharing many features with other antineoplastic drugs in terms of their mechanisms of action. Among these common mechanisms of action are the regulation of several major intracellular pathways including mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) and protein kinase B (AKT/PKB) signaling. The important mediators affected by melatonin include cyclins, nuclear factor-κB (NF-κB), heat shock proteins (HSPs) and c-Myc, all of which can serve as potential targets for cancer drugs. Melatonin also exerts some of its anti-cancer effects via inducing epigenetic modifications, DNA damage and mitochondrial disruption in malignant cells. The regulation of these mediators by melatonin mitigates tumor growth and invasiveness via modulating their downstream responsive genes, housekeeping enzymes, telomerase reverse transcriptase, apoptotic gene expression, angiogenic factors and structural proteins involved in metastasis. Increasing our knowledge on how melatonin affects its target sites will help find ways of exploiting the beneficial effects of this ubiquitously-acting molecule in cancer therapy. Acknowledging this, here we reviewed the most studied target pathways attributed to the anti-cancer effects of melatonin, highlighting their therapeutic potential.

Occurrence of melatonin and indolic compounds derived from l-tryptophan yeast metabolism in fermented wort and commercial beers

Melatonin and serotonin are bioactive compounds present in foods and beverages and related to neuroprotection and anti-angiogenesis, among other activities. They have been described in wines and the role of yeast in their formation is clear. Thus, this study evaluates the content of these bioactives and other related indolic compounds in beer. For this purpose, commercial beers were analyzed by a validated UHPLC-HRMS method and sample treatment optimized due to the low concentrations expected. Moreover, a wort was fermented with different commercial beer yeast (Abbaye, Diamond, SafAle, SafLager) in order to monitor the formation of these bioactives during the elaboration process. Results show that indolic compounds such as N-acetylserotonin and 3-indoleacetic acid are produced during the alcoholic fermentation of wort. Moreover, the occurrence of four indolic compounds (5-hydroxytryptophan, N-acetylserotonin, 3-indoleacetic acid, l-tryptophan ethyl ester) in commercial beers is reported for the first time.

Melatonin prevents the binding of vascular endothelial growth factor to its receptor and promotes the expression of extracellular matrix-associated genes in nucleus pulposus cells

The mechanisms of intervertebral disc degeneration (IDD) involve numerous factors, including loss of the extracellular matrix (ECM) and vascular ingrowth. Melatonin has been reported to protect intervertebral discs (IVDs) from degeneration and to exert a potential anti-angiogenic effect. The aim of the present study was to investigate the anti-angiogenic and anabolic effects of melatonin in IVDs. Human nucleus pulposus (NP) and degenerative nucleus pulposus (DNP) cells were isolated and treated with melatonin. The results indicated that melatonin promoted ECM synthesis and NP cell proliferation. In addition, an NP/DNP and human umbilical vein endothelial cell (HUVEC) co-culture model was used to investigate the anti-angiogenesis effect of melatonin. Melatonin was indicated to suppress tube formation and migration of HUVECs in culture with NP cell-conditioned medium, as well as in an NP cell co-culture model. Fluorescence-labeled vascular endothelial growth factor (VEGF) was used to study the binding between VEGF and its receptor. The results of the present study indicated that melatonin exerts an angiogenic effect via inhibition of the binding of VEGF to its receptor in HUVECs. Taken together, these results suggest that melatonin is a potential agent to prevent IDD.

Analysis of plant-derived phytochemicals as anti-cancer agents targeting cyclin dependent kinase-2, human topoisomerase IIa and vascular endothelial growth factor receptor-2

Cancer is caused by a variety of pathways, involving numerous types of enzymes. Among them three enzymes i.e. Cyclin-dependent kinase-2 (CDK-2), Human topoisomerase IIα, and Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) are three of the most common enzymes that are involved in the cancer development. Although many chemical drugs are already available in the market for cancer treatment, plant sources are known to contain a wide variety of agents that are proved to possess potential anticancer activity. In this experiment, total thirty phytochemicals were analyzed against the mentioned three enzymes using different tools of bioinformatics and in silico biology like molecular docking study, drug likeness property experiment, ADME/T test, PASS prediction, and P450 site of metabolism prediction as well as DFT calculation to determine the three best ligands among them that have the capability to inhibit the mentioned enzymes. From the experiment, Epigallocatechin gallate was found to be the best ligand to inhibit CDK-2, Daidzein showed the best inhibitory activities towards the Human topoisomerase IIα, and Quercetin was predicted to be the best agent against VEGFR-2. They were also predicted to be quite safe and effective agents to treat cancer. However, more in vivo and in vitro analyses are required to finally confirm their safety and efficacy in this regard.

To beer or not to beer: A meta-analysis of the effects of beer consumption on cardiovascular health

A moderate alcohol consumption is demonstrated to exert a protective action in terms of cardiovascular risk. Although this property seems not to be beverage-specific, the various composition of alcoholic compounds could mediate peculiar effects in vivo. The aim of this study was to evaluate potential beer-mediated effects on the cardiovascular health in humans, using a meta-analytic approach (trial registration number: CRD42018118387). The literature search, comprising all English articles published until November, 30th 2019 in EMBASE, PubMed and Cochrane database included all controlled clinical trials evaluating the cardiovascular effects of beer assumption compared to alcohol-free beer, water, abstinence or placebo. Both sexes and all beer preparations were considered eligible. Outcome parameters were those entering in the cardiovascular risk charts and those related to endothelial dysfunction. Twenty-six trials were included in the analysis. Total cholesterol was significantly higher in beer drinkers compared to controls (14 studies, 3.52 mg/dL, 1.71–5.32 mg/dL). Similar increased levels were observed in high-density lipoprotein (HDL) cholesterol (18 studies, 3.63 mg/dL, 2.00–5.26 mg/dL) and in apolipoprotein A1 (5 studies, 0.16 mg/dL, 0.11–0.21 mg/dL), while no differences were detected in low density lipoprotein (LDL) cholesterol (12 studies, -2.85 mg/dL, -5.96–0.26 mg/dL) and triglycerides (14 studies, 0.40 mg/dL, -5.00–5.80 mg/dL) levels. Flow mediated dilation (FMD) resulted significantly higher in beer-consumers compared to controls (4 studies, 0.65%, 0.07–1.23%), while blood pressure and other biochemical markers of inflammation did not differ. In conclusion, the specific beer effect on human cardiovascular health was meta-analysed for the first time, highlighting an improvement of the vascular elasticity, detected by the increase of FMD (after acute intake), and of the lipid profile with a significant increase of HDL and apolipoprotein A1 serum levels. Although the long-term effects of beer consumption are not still understood, a beneficial effect of beer on endothelial function should be supposed.

Melatonin: An atypical hormone with major functions in the regulation of angiogenesis

Melatonin (N-acetyl-5-methoxytryptamine), a pleotropic molecule with a wide distribution, has received considerable attention in recent years, mostly because of its various major effects on tissues or cells since it has both receptor-dependent and receptor-independent actions over a wide range of concentrations. These biological and physiological functions of melatonin include regulation of circadian rhythms by modulating the expression of core oscillator genes, scavenging the reactive oxygen species and reactive nitrogen species, modulating the immune system and inflammatory response, and exerting cytoprotective and antiapoptotic effects. Given the multiple critical roles of melatonin, dysregulation of its production or any disruption in signaling through its receptors may have contributed in the development of a wide range of disorders including type 2 diabetes, aging, immune-mediated diseases, hypertension, and cancer. Herein, we focus on the modulatory effects of melatonin on angiogenesis and its implications as a therapeutic strategy in cancer and related diseases.

Calcium dobesilate reduces VEGF signaling by interfering with heparan sulfate binding site and protects from vascular complications in diabetic mice

Inhibiting vascular endothelial growth factor (VEGF) is a therapeutic option in diabetic microangiopathy. However, VEGF is needed at physiological concentrations to maintain glomerular integrity; complete VEGF blockade has deleterious effects on glomerular structure and function. Anti-VEGF therapy in diabetes raises the challenge of reducing VEGF-induced pathology without accelerating endothelial cell injury. Heparan sulfate (HS) act as a co-receptor for VEGF. Calcium dobesilate (CaD) is a small molecule with vasoprotective properties that has been used for the treatment of diabetic microangiopathy. Preliminary evidence suggests that CaD interferes with HS binding sites of fibroblast growth factor. We therefore tested the hypotheses that (1) CaD inhibits VEGF signaling in endothelial cells, (2) that this effect is mediated via interference between CaD and HS, and (3) that CaD ameliorates diabetic nephropathy in a streptozotocin-induced diabetic mouse model by VEGF inhibition. We found that CaD significantly inhibited VEGF₁₆₅-induced endothelial cell migration, proliferation, and permeability. CaD significantly inhibited VEGF₁₆₅-induced phosphorylation of VEGFR-2 and suppressed the activity of VEGFR-2 mediated signaling cascades. The effects of CaD in vitro were abrogated by heparin, suggesting the involvement of heparin-like domain in the interaction with CaD. In addition, VEGF₁₂₁, an isoform which does not bind to heparin, was not inhibited by CaD. Using the proximity ligation approach, we detected inhibition of interaction in situ between HS and VEGF and between VEGF and VEGFR-2. Moreover, CaD reduced VEGF signaling in mice diabetic kidneys and ameliorated diabetic nephropathy and neuropathy, suggesting CaD as a VEGF inhibitor without the negative effects of complete VEGF blockade and therefore could be useful as a strategy in treating diabetic nephropathy.

Intravenous anti-VEGF agents with RGD peptide-targeted core cross-linked star (CCS) polymers modified with indocyanine green for imaging and treatment of laser-induced choroidal neovascularization

S-PEG-ICG-RGD-RBZ NPs were synthesized to intravenously deliver anti-VEGF agents to choroidal neovascularization (CNV) areas for the treatment of CNV.

Role of melatonin in controlling angiogenesis under physiological and pathological conditions

Angiogenesis depends on proangiogenic and anti-angiogenic molecules that regulate endothelial cell proliferation and migration. Well-regulated angiogenesis plays a pivotal role in many physiological conditions such as reproduction and embryonic development, while abnormal angiogenesis is also the basis of a variety of pathological processes including tumor metastasis and atherosclerotic plaque formation. Melatonin has a variety of biological effects, including inhibition of tumor metastasis, stabilizing atherosclerotic plaques, and the regulation of seasonal reproductive rhythms, etc. During certain pathophysiological processes, melatonin exerts different functions depending on its ability to regulate angiogenesis. This review reveals that melatonin has different effects on neovascularization under different physiological and pathological conditions. In tumors, in age-related ocular diseases, and in a hypoxic environment, melatonin inhibits neovascularization in tissues, while in gastric ulcers, skin lesions, and some physiologic processes, it promotes angiogenesis. We also speculate that melatonin may inhibit the neovascularization in atherosclerotic plaques, thus preventing the initiation and development of atherosclerosis. Most studies suggest that these effects are related to the role of melatonin in regulating of vascular endothelial growth factor and its receptors, but the specific regulatory mechanisms remain disparate, which may lead to the differential effects of melatonin on angiogenesis under different conditions. In this review, we thus summarize some seemingly contradictory mechanisms by which melatonin controls angiogenesis under different pathological and physiological conditions, and urge that the regulatory mechanisms be further studied.

Anti-VEGF Signalling Mechanism in HUVECs by Melatonin, Serotonin, Hydroxytyrosol and Other Bioactive Compounds

Angiogenesis drives evolution and destabilisation of atherosclerotic plaques and the growth and expansion of tumour cells. Vascular endothelial growth factor (VEGF) is the main endogenous pro-angiogenic factor in humans. The aim was to provide insight into the anti-VEGF activity of bioactive compounds derived from aromatic amino acids (serotonin, melatonin, 3-indoleacetic acid, 5-hydroxytryptophol and hydroxytyrosol). Experiments involved endothelial cell migration (wound-healing assay), the molecular mechanisms (ELISA assay) and the downstream effects (phospholipase C gamma 1 (PLCγ1), protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS) by Western blot) on human umbilical vein endothelial cells (HUVECs). The data suggest for the first time that hydroxytyrosol interacts with surface components of the endothelial cell membrane (, preventing VEGF from activating its receptor. Serotonin and 5-hydroxytryptophol significantly inhibited HUVEC migration (98% and 50%, respectively) following the same mechanism. Conversely to other bioactive compounds, the anti-angiogenic effect of melatonin, serotonin, 3-indoleacetic acid and 5-hydroxytryptophol is not mediated via PLCγ1. However, hydroxytyrosol inhibits PLCγ1 phosphorylation. Additionally, melatonin and serotonin maintained eNOS phosphorylation and hydroxytyrosol significantly activated eNOS—all via Akt. These data provide new evidence supporting the interest in melatonin, serotonin, 3-indoleacetic acid, 5-hydroxytryptophol and hydroxytyrosol for their further exploitation as anti-VEGF ingredients in food.

Promoting effect of baicalin on nitric oxide production in CMECs via activating the PI3K-AKT-eNOS pathway attenuates myocardial ischemia-reperfusion injury

OBJECTIVE

Baicalin, which is isolated from Scutellariae Radix, has been shown to possess therapeutic potential for different diseases. Cardiac microvessel injury in myocardial ischemia-reperfusion (IR) has been extensively explored. However, there have been no studies investigating the physiological regulatory mechanisms of baicalin on nitric oxide production and the necroptosis of cardiac microvascular endothelial cells (CMECs) in myocardial IR injury. This study was designed to investigate the contribution of baicalin to repressing necroptosis and preventing IR-mediated CMEC dysfunction.

MATERIALS AND METHODS

Indicators of ventricular structure and function were measured by an echocardiographic system. An MTT assay was performed to assess cell viability. Nitrite detection was performed to detect nitric oxide content, and cGMP content was determined using a commercially available cGMP complete ELISA kit. Morphology and molecular characteristics were detected by electron micrographs, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting.

RESULT

Our results demonstrated that baicalin significantly improved cardiac function, decreased the myocardial infarction area, and inhibited myocardial cell apoptosis. Moreover, baicalin had a protective effect on cardiac microvessels and promoted the production of nitric oxide (NO) and the level of cGMP in rats that underwent myocardial IR injury. The results of the in vitro experiments showed that baicalin markedly improved cell activity and function in CMECs exposed to hypoxia-reoxygenation (HR). Further experiments indicated that baicalin supplementation suppressed the protein expression of RIP1, RIP3 and p-MLKL to interrupt CMEC necroptosis. In addition, baicalin promoted the production of NO via activating the PI3K-AKT-eNOS signaling pathway. Taken together, our results identified the PI3K-AKT-eNOS axis as a new pathway responsible for reperfusion-mediated microvascular damage.

CONCLUSION

Baicalin protected CMECs in IR rats by promoting the release of NO via the PI3K-AKT-eNOS pathway and mitigated necroptosis by inhibiting the protein expression of RIP1, RIP3 and p-MLKL.

Risk assessment methodologies in the field of contaminants, food contact materials, technological ingredients and nutritional risks

The programme aimed at training the fellow in the risk assessment guidelines proposed by the EFSA in the field of contaminants, food contact materials, technological ingredients and nutritional risks. It had a modular 'learning by doing' approach and a balanced learning/case studies and theory. Module 1 offered an insight into chemical risk assessment and conferred transferable skills for a proper application of the framework. The hands-on activities consisted of three case studies that went from a simple exercise on an official opinion, to working in a team with experts to produce a new opinion, to an individual work to obtain a publishable review manuscript. Module 2 was a training in experimental toxicology designed to create a toxicological basis and to enable the fellow to perform toxicological studies for risk assessment purposes. She joined the team working on cyanotoxins, gained experience with both EFSA and Organization of Economic Cooperation and Development (OECD) guidelines on genotoxicity and an insight into the developing of analytical methods suitable for risk assessment purposes. During module 3, the fellow was trained in nutritional risk assessment and involved in experimental work in chemical characterisation, biomarkers and mechanisms of action of bioactive compounds. This developed the critical perspective when assessing nutritional and health claims related the design of experiments, methods used, interpretation of results and human relevance. Module 4 provided a 'hand-on experience' in scientific risk communication as the fellow was encouraged and supported in the participation at local, national and international workshops and congresses presenting the outcomes of the three modules. Thus, the fellow was successfully integrated in the day-by-day workflow of the department, gaining first-hand practical experience in risk assessment in a multicultural and interdisciplinary context. This enabled a productive exchange of good practices and contributed to building a European risk assessment community.

Melatonin, protocatechuic acid and hydroxytyrosol effects on vitagenes system against alpha-synuclein toxicity

Preventing the abnormal assembly of α-synuclein (α-Syn) and the correct modulation of vitagenes system exercise strong neuroprotective effects. It has been reported that melatonin (MEL), protocatechuic acid (PCA) and hydroxytyrosol (HT) reduce α-Syn toxicity. Their effect on the vitagenes system of PC12 cells have not been explored yet. These bioactive can cross the blood brain barrier (BBB). Therefore, this work aims to evaluate the inhibitory and destabilising capacities of MEL, PCA, HT, and their combinations on α-Syn kinetics and effects on vitagenes system (sirtuin-1 (SIRT-1), sirtuin-2 (SIRT-2), heme oxygenase (HO-1) and heat shock protein 70 (Hsp-70)). In vitro techniques (Thioflavin T (ThT), Transmission Electronic Microscopy (TEM), electrophoresis, MTT assay and qPCR) were used. Compounds, both individually and simultaneously were able to decrease the toxicity induced by α-Syn. Concurrently, occurrence of PCA (100 μM) +HT (100 μM) showed the highest inhibitory effect against α-Syn fibril formation and destabilisation of α-Syn fibrils (88 and 62%, respectively). Moreover, these compounds increased the expression of SIRT-2, HO-1 and Hsp70, contributing to a neuroprotective effect. In addition, the most important result is the increase on the expression of SIRT-2 caused by the combination of MEL + HT + PCA in the absence of α-Syn fibrils.

Anti-Tumor Activity and Pharmacokinetics of AP25-Fc Fusion Protein

AP25 is an anti-tumor peptide with a high affinity for integrins. It exerts its anti-tumor activity by inhibiting angiogenesis and by directly inhibiting the growth of tumor cells. Its half-life time in vivo is only about 50 minutes, which limits its clinical application. In order to prolong the half-life time of AP25 while preserving its anti-tumor activity, several fusion proteins of AP25 and IgG4 Fc were designed and expressed; their anti-tumor activity and pharmacokinetics properties were evaluated. Firstly, four AP25-Fc fusion protein sequences were designed, and the corresponding proteins were expressed and purified. Based on the results of HUVEC migration inhibition assay, HUVEC and tumor cell proliferation inhibition assay and yields of expression by HEK293 cells, the fusion protein designated PSG4R was selected for further evaluation. The anti-tumor effect of PSG4R was then evaluated in vivo on HCT-116 nude mice xenograft model. And the pharmacokinetics properties of PSG4R were investigated in rats. The results showed that PSG4R could inhibit the growth of xenografts of human colon cancer cell line HCT-116 in nude mice by intravenous administration of 40 mg/kg once every two days. The half-life time of PSG4R was 56.270 ± 15.398 h. This study showed that the construction of AP25-Fc fusion protein could significantly prolong the half-life of AP25 while retaining its anti-tumor activity, which provides a new direction for new drug development of AP25.

Ginsenoside Rb1 promotes the growth of mink hair follicle via PI3K/AKT/GSK-3β signaling pathway

AIMS

Hair follicles play a critical role in the process of hair growth. The dermal papilla cells (DPCs) are an important component in the hair follicle regeneration and growth. This study investigated the effects of ginsenoside Rb1 on the growth of cultured mink hair follicles and DPCs.

MAIN METHODS

The mink hair follicles were treated with ginsenoside Rb1 for 9 days and their lengths were measured every three days. Real-time PCR was used to determine the mRNA expression of vascularization endothelial growth factor A (VEGF-A), VEGF receptor 2 (VEGF-R2) and TGF-β1. In addition, the levels of proteins were detected by western blot. Cell proliferation was determined by immunofluorescence staining of proliferation marker Ki-67 and cell cycle analysis was performed on flow cytometry. Moreover, cell migration was evaluated by wound healing assay.

KEY FINDINGS

Ginsenoside Rb1 promoted the growth of hair follicles, and proliferation and migration of DPCs. Ginsenoside Rb1 improved the expression levels of VEGFA and VEGF-R2, while attenuated the TGF-β1 expression both in hair follicles and DPCs. Furthermore, ginsenoside Rb1 facilitated the activation of PI3K/AKT/GSK-3β signaling pathway in hair follicles and DPCs.

SIGNIFICANCE

The results reveals a crucial role of PI3K/AKT/GSK-3β signaling pathway in ginsenoside Rb1-induced growth of hair follicles and DPCs.

Discovery of Dioxino[2,3-f]quinazoline derivative VEGFR-2 inhibitors exerting significant antipro-liferative activity in HUVECs and mice

Twelve 2,3-dihydro-[1,4]-dioxino[2,3-f]quinazoline derivatives were designed and evaluated as vascular endothelial growth factor receptor 2 (VEGFR-2) inhibitors. The most half-maximal inhibitory concentration (IC₅₀) values of them were less than 10 nM. Among these compounds, 13d displayed highly effective inhibitory activity against VEGFR-2 (IC₅₀ = 2.4 nM) and excellent antiproliferative activities against human umbilical vein endothelial cells (HUVECs) (IC₅₀ = 1.2 nM). When anti-tumor animal experiments were carried out in mice, the tumor almost disappeared (TGI = 133.0%) after six days of administration of 13d. Therefore, 13d was a potential and effective anticancer agent. The binding conformations were respectively compared between VEGFR-2 with 13d and leading compound lenvatinib, and shows that they have similar binding modes.

Allicin improves the function of cardiac microvascular endothelial cells by increasing PECAM-1 in rats with cardiac hypertrophy

OBJECTIVE

Cardiac microvascular damage is significantly associated with the development of cardiac hypertrophy (CH). Researchers found that allicin could inhibit CH, but the relationship between cardiac microvessel and the inhibition of allicin on CH has not been reported. We aimed to investigate the effect of allicin on the function of cardiac microvascular endothelial cells (CMECs) in CH rat.

MATERIALS AND METHODS

The hemodynamic parameters were measured by BL-420F biological function experimental system and the indicators of the ventricular structure and function were measured by echocardiographic system. MTT assay was performed to assess the cell viability. Nitrite detection was performed to detect nitric oxide content. The morphology and molecular characteristics were detected by electron micrographs, immunofluorescence, quantitative real-time polymerase chain reaction (qRT-PCR), western blot. Wound healing experiment, analysis of tube formation and shear adaptation were performed to assess CMECs migration ability, angiogenesis and shear-responsiveness respectively.

RESULT

Our findings have identified that microvascular density was decreased by observing the expression of platelet endothelial cell adhesion molecule-1 (PECAM-1) in CH rats. Interestingly, allicin improved the distribution and expression of PECAM-1. Meanwhile, allicin enhanced the migration and angiogenesis ability of CMECs, activated PECAM-1-PI3K-AKT-eNOS signaling pathway, however, the role of allicin was disappear after PECAM-1 was silenced. Allicin decreased the expression of caspase-3 and receptor interacting protein 3 (RIP3), inhibited necroptosis, and increased the levels of Angiopoietin-2 (Ang-2) and platelet-derived growth factor receptor-β (PDGFR-β). Under 10 dyn/cm² condition, allicin advanced the modification ability of CMECs's shear-adaptation by activating PECAM-1.

CONCLUSION

Allicin provided cardioprotection for CH rats by improving the function of CMECs through increasing the expression of PECAM-1.

Melatonin and age-related cardiovascular diseases

The pineal gland is a neuroendocrine gland closely related to human aging. Melatonin is a kind of indole neuroendocrine hormone secreted by the pineal gland, which is essential for maintaining physiological function. Many researches found that melatonin plays a key role in anti-aging-related cardiovascular diseases. In this paper, the latest advances in the study of melatonin and aging-related cardiovascular diseases are reviewed, and their related physiological functions and mechanisms are discussed.

Long noncoding RNA TCONS_00024652 regulates vascular endothelial cell proliferation and angiogenesis via microRNA-21

Acute coronary syndrome caused by the rupture of atherosclerotic plaques is one of the primary causes of major cardiovascular events, and neovascularization within the plaque is closely associated with its stability. Long noncoding RNA (lncRNAs) is a type of noncoding RNA that serves a crucial role in regulating vascular endothelial cells (VECs). The aim of the present study was to investigate the effect of lncRNA TCONS_00024652 on the proliferation and angiogenesis of VECs following stimulation with TNF-α. The expression of lncRNA and miRNA was measured in human umbilical vein endothelial cells (HUVECs) by reverse transcription-quantitative polymerase chain reaction. Cell proliferation was measured using a Cell Counting Kit-8 assay. Wound healing and tube formation assays were performed to determine cell migration and angiogenesis. Interactions between TCONS_00024652 and miR-21 were determined using bioinformatics and a dual-luciferase reporter assay. The results demonstrated that TCONS_00024652 is highly expressed in TNF-α-induced HUVECs. Functional assays demonstrated that the dysregulated expression of TCONS_00024652 promotes endothelial cell proliferation and angiogenesis, whereas TCONS_00024652 knockdown induces the opposite effects. Bioinformatics analysis using starBase predicted putative binding at the 3′-untranslated region of TCONS_00024652 and miR-21 and luciferase reporter assays further verified this interaction. The results of the present study suggest that the targeting of TCONS_00024652 by miR-21 may be a potential method of improving vascular endothelial dysfunction, neovascularization maturation and plaque stabilization.

Total Flavones of Abelmoschus manihot Exhibits Pro-Angiogenic Activity by Activating the VEGF-A/VEGFR2-PI3K/Akt Signaling Axis

Angiogenesis is a process of new blood vessel formation from pre-existing vessels. Vascular endothelial growth factor-A (VEGF-A) binds to VEGF receptor-2 (VEGFR2) and thus activation of phosphatidylinositol 3-kinase (PI3K)/Akt pathway play a central role in angiogenesis. Total flavones of Abelmoschus manihot (TFA), the major active component of the traditional Chinese herb Abelmoschus manihot, display novel pro-angiogenic activity. However, little information concerning its underlying mechanism is available. Here we investigate the pro-angiogenesis of TFA with the aim of understanding its mechanism of action. Human umbilical vein endothelial cells (HUVECs) and the chick chorioallantoic membrane (CAM) model were used to evaluate pro-angiogenesis of TFA using cell viability, wounding healing, transwell invasion, tube formation, RT-qPCR and Western blot methods. LY294002, a PI3K inhibitor, was used to interfere with PI3K/Akt pathway signal for assessing the underlying mechanism. Results in vitro indicated TFA obviously promoted HUVECs proliferation, migration, invasion and tube formation. Furthermore, TFA markedly augmented PI3K and Akt phosphorylation and up-regulated VEGF-A and VEGFR2 expression in HUVECs. However, pre-treatment with LY294002 not only markedly attenuated TFA-induced cells proliferation, migration, invasion and tube formation, but also significantly abolished TFA-induced VEGF-A and VEGFR2 over-expression as well as PI3K and Akt phosphorylation. Experiments in CAM model showed TFA significantly promoted the formation of branched blood vessels and was dramatically suppressed by LY294002. Taken together, TFA promoted angiogenesis both in vitro and in vivo which, however, were counteracted by LY294002, suggesting at least in part, TFA exhibits pro-angiogenic activity by activating the VEGF-A/VEGFR2-PI3K/Akt signaling axis.

Melatonin and Cancer Hallmarks

Melatonin is a natural indoleamine produced by the pineal gland that has many functions, including regulation of the circadian rhythm. Many studies have reported the anticancer effect of melatonin against a myriad of cancer types. Cancer hallmarks include sustained proliferation, evading growth suppressors, metastasis, replicative immortality, angiogenesis, resisting cell death, altered cellular energetics, and immune evasion. Melatonin anticancer activity is mediated by interfering with various cancer hallmarks. This review summarizes the anticancer role of melatonin in each cancer hallmark. The studies discussed in this review should serve as a solid foundation for researchers and physicians to support basic and clinical studies on melatonin as a promising anticancer agent.

Effects of melatonin on mechanisms involved in hypertension using human umbilical vein endothelial cells

Changes in diurnal rhythmicity in blood pressure (BP) are associated with hypertension and consequent cardiovascular damage. The involvement of diurnal rhythmicity as a pathogenic factor in hypertension is not fully understood. Since the hormone melatonin (MLT) regulates circadian rhythm, it was also of interest to determine whether this hormone played a role in hypertension-related alterations in circadian rhythm. Thus the aim of this study was to examine the mechanisms underlying MLT-mediated antihypertension. Human umbilical vein endothelial cells were incubated with MLT under 25 kPa pressure to simulate hypertension. Vasoactive substances including endothelin (ET), angiotensin II (Ang II), nitric oxide (NO), and endothelial nitric oxide synthase (eNOS) were measured using ELISA assays. Results showed that MLT produced a significant decrease in ET at 18 and 24 h and Ang II at 18 h after treatment. In contrast, MLT significantly elevated NO levels and eNOS activity at 6, 12, 18, and 24 h, indicating that these oxidant indicators may be more sensitive to MLT-induced actions. Gene chip analysis identified 121 upregulated and 214 downregulated genes at 6 h after MLT treatment, predominantly involved in DNA replication, cell cycle regulation, amino acid metabolism, and cell cycle pathway. At 18 h, 63 upregulated and 94 downregulated genes involved in circadian entrainment, cGMP-PKG signaling pathway involved in NO synthesis, as well as secretion of renin and insulin, which are associated with BP regulation. Data suggest that the circadian antihypertensive effects of MLT might be associated with decrease in ET and Ang II, accompanied by rise in NO and eNOS and that NO and eNOS appear to be early bioindicators of hormonal effect.

Melatonin and Fertoprotective Adjuvants: Prevention against Premature Ovarian Failure during Chemotherapy

Premature ovarian failure is one of the side effects of chemotherapy in pre-menopausal cancer patients. Preservation of fertility has become increasingly important in improving the quality of life of completely recovered cancer patients. Among the possible strategies for preserving fertility such as ovarian tissue cryopreservation, co-treatment with a pharmacological adjuvant is highly effective and poses less of a burden on the human body. Melatonin is generally produced in various tissues and acts as a universally acting antioxidant in cells. Melatonin is now more widely used in various biological processes including treating insomnia and an adjuvant during chemotherapy. In this review, we summarize the information indicating that melatonin may be useful for reducing and preventing premature ovarian failure in chemotherapy-treated female patients. We also mention that many adjuvants other than melatonin are developed and used to inhibit chemotherapy-induced infertility. This information will give us novel insights on the clinical use of melatonin and other agents as fertoprotective adjuvants for female cancer patients.