The Use of Microbial Modifying Therapies to Prevent Psoriasis Exacerbation and Associated Cardiovascular Comorbidity

Psoriasis has emerged as a systemic disease characterized by skin and joint manifestations as well as systemic inflammation and cardiovascular comorbidities. Many progresses have been made in the comprehension of the immunological mechanisms involved in the exacerbation of psoriatic plaques, and initial studies have investigated the mechanisms that lead to extracutaneous disease manifestations, including endothelial disfunction and cardiovascular disease. In the past decade, the involvement of gut dysbiosis in the development of pathologies with inflammatory and autoimmune basis has clearly emerged. More recently, a major role for the skin microbiota in establishing the immunological tolerance in early life and as a source of antigens leading to cross-reactive responses towards self-antigens in adult life has also been evidenced. Gut microbiota can indeed be involved in shaping the immune and inflammatory response at systemic level and in fueling inflammation in the cutaneous and vascular compartments. Here, we summarized the microbiota-mediated mechanisms that, in the skin and gut, may promote and modulate local or systemic inflammation involved in psoriatic disease and endothelial dysfunction. We also analyze the emerging strategies for correcting dysbiosis or modulating skin and gut microbiota composition to integrate systemically existing pharmacological therapies for psoriatic disease. The possibility of merging systemic treatment and tailored microbial modifying therapies could increase the efficacy of the current treatments and potentially lower the effect on patient's life quality.

Emerging Microfluidic Tools for Simultaneous Exosomes and Cargo Biosensing in Liquid Biopsy: New Integrated Miniaturized FFF-Assisted Approach for Colon Cancer Diagnosis

The early-stage diagnosis of cancer is a crucial clinical need. The inadequacies of surgery tissue biopsy have prompted a transition to a less invasive profiling of molecular biomarkers from biofluids, known as liquid biopsy. Exosomes are phospholipid bilayer vesicles present in many biofluids with a biologically active cargo, being responsible for cell-to-cell communication in biological systems. An increase in their excretion and changes in their cargo are potential diagnostic biomarkers for an array of diseases, including cancer, and they constitute a promising analyte for liquid biopsy. The number of exosomes released, the morphological properties, the membrane composition, and their content are highly related to the physiological and pathological states. The main analytical challenge to establishing liquid biopsy in clinical practice is the development of biosensors able to detect intact exosomes concentration and simultaneously analyze specific membrane biomarkers and those contained in their cargo. Before analysis, exosomes also need to be isolated from biological fluids. Microfluidic systems can address several issues present in conventional methods (i.e., ultracentrifugation, size-exclusion chromatography, ultrafiltration, and immunoaffinity capture), which are time-consuming and require a relatively high amount of sample; in addition, they can be easily integrated with biosensing systems. A critical review of emerging microfluidic-based devices for integrated biosensing approaches and following the major analytical need for accurate diagnostics is presented here. The design of a new miniaturized biosensing system is also reported. A device based on hollow-fiber flow field-flow fractionation followed by luminescence-based immunoassay is applied to isolate intact exosomes and characterize their cargo as a proof of concept for colon cancer diagnosis.

Peto's paradox: Nature has used multiple strategies to keep cancer at bay while evolving long lifespans and large body masses. A systematic mini-review

Comparative oncology is an understudied field of science. We are far from understanding the key mechanisms behind Peto's paradox, i.e., understanding how long-lived and large animals are not subject to a higher cancer burden despite the longer exposure time to mutations and the larger number of cells exposed. In this work, we investigated the scientific evidence on such mechanisms through a systematic mini-review of the literature about the relation of longevity and/or large body mass with physiological, genetic, or environmental traits among mammalian species. More than forty thousand articles were retrieved from three repositories, and 383 of them were screened using an active-learning-based tool. Of those, 36 articles on longevity and 37 on body mass were selected for the review. Such articles were examined focusing on: number and type of species considered, statistical methods used, traits investigated, and observed relationship with longevity and/or body mass. Where applicable, the traits investigated were matched with one or more hallmarks of cancer. We obtained a list of potential candidate traits to explain Peto's paradox related to replicative immortality, cell senescence, genome instability and mutations, proliferative signaling, growth suppression evasion, and cell resistance to death. Our investigation suggests that different strategies have been followed to prevent cancer in large and long-lived species. The large number of papers retrieved emphasizes that more studies can be launched in the future, using more efficient analytical approaches to comprehensively evaluate the convergent biological mechanisms essential for acquiring longevity and large body mass without increasing cancer risk.

The spontaneous immortalization probability of mammalian cell culture strains, as their proliferative capacity, correlates with species body mass, not longevity

BACKGROUND

The Peto's paradox consists in the observation that individuals from long-lived and large animal species do not experience a higher cancer incidence, despite being exposed for longer time to the possibility of accumulating mutations and having more target cells exposed to the phenomenon. The existence of this paradox has been recently confirmed (Vincze et al., 2022). Concurrently, robust evidence has been published that longevity involves a convergent evolution of cellular mechanisms that prevent the accumulation of mutations (Cagan et al., 2022). It remains unclear which cellular mechanisms are critical to allow the evolution of a large body mass while keeping cancer at bay.

METHODS

Adding to existing data linking cellular replicative potential and species body mass (Lorenzini et al., 2005), we have grown a total of 84 skin fibroblast cell strains from 40 donors of 17 mammalian species and analyzed their Hayflick's limit, i.e., their senescent plateau, and eventual spontaneous immortalization escape. The correlation of immortalization and replicative capacity of the species with their longevity, body mass and metabolism has been assessed through phylogenetic multiple linear regression (MLR).

RESULTS

The immortalization probability is negatively related to species body mass. The new evaluation and additional data about replicative potential strengthen our previous observation, confirming that stable and extended proliferation is strongly correlated with the evolution of a large body mass rather than lifespan.

CONCLUSION

The relation between immortalization and body mass suggests a need to evolve stringent mechanisms that control genetic stability during the evolution of a large body mass.

Treatment with PCSK9 Inhibitor Evolocumab Improves Vascular Oxidative Stress and Arterial Stiffness in Hypercholesterolemic Patients with High Cardiovascular Risk

Atherosclerosis and atherosclerotic-related cardiovascular diseases (ASCVD) are characterized by high serum levels of low-density lipoprotein cholesterol (LDL-C) that can promote the generation of reactive oxygen species (ROS). To answer the need for better LDL-C control in individuals at high and very high risk for CVD, a new injectable innovative family of lipid-lowering (LL) monoclonal antibodies against the protein convertase subtilisin/kexin type 9 (PCSK9) has been approved. However, the effect of these drugs on vascular function, such as ROS generation and arterial stiffness, has not already been extensively described. In this report, we present data from 18 males with high to very high CV risk undergoing LL treatment (LLT) with either statin and ezetimibe or ezetimibe monotherapy, who experienced, after a 2-month treatment with Evolocumab, a significant improvement in blood pressure (BP)-adjusted carotid–femoral pulse wave velocity (cfPWV) (p-value = 0.0005 in the whole cohort, p-value = 0.0046 in the sub-cohort undergoing background LLT with statin and ezetimibe, p-value = 0.015 in the sub-cohort undergoing background LLT with ezetimibe monotherapy), which was significantly associated with a decrease in freshly isolated leukocytes (PBMCS)-derived H2O2 production (p-value = 0.004, p-value = 0.02 and p-value = 0.05, respectively, in the whole cohort, in the statin + ezetimibe sub-cohort, and the ezetimibe sub-cohort). Our observations support the role of systemic oxidative stress in atherosclerosis and give a further rationale for using Evolocumab also for its effect in vascular disorders linked to oxidative processes.

New Insights into Bile Acids Related Signaling Pathways in the Onset of Colorectal Cancer

Colorectal cancer (CRC) ranks as the second among the causes of tumor death worldwide, with an estimation of 1.9 million new cases in 2020 and more than 900,000 deaths. This rate might increase by 60% over the next 10 years. These data are unacceptable considering that CRC could be successfully treated if diagnosed in the early stages. A high-fat diet promotes the hepatic synthesis of bile acids (BAs) increasing their delivery to the colonic lumen and numerous scientific reports correlate BAs, especially secondary BAs, with CRC incidence. We reviewed the physicochemical and biological characteristics of BAs, focusing on the major pathways involved in CRC risk and progression. We specifically pointed out the role of BAs as signaling molecules and the tangled relationships among their nuclear and membrane receptors with the big bang of molecular and cellular events that trigger CRC occurrence.

Effect of Lactobacillus acidophilus Fermented Broths Enriched with Eruca sativa Seed Extracts on Intestinal Barrier and Inflammation in a Co-Culture System of an Enterohemorrhagic Escherichia coli and Human Intestinal Cells

Lactic acid bacteria (LAB) “fermentates” confer a beneficial effect on intestinal function. However, the ability of new fermentations to improve LAB broth activity in preventing pathogen-induced intestinal inflammation and barrier dysfunction has not yet been studied. The objective of this study was to determine if broths of LAB fermented with Eruca sativa or Barbarea verna seed extracts prevent gut barrier dysfunction and interleukin-8 (CXCL8) release in vitro in human intestinal Caco-2 cells infected with enterohemorrhagic Escherichia coli (EHEC) O157:H7. LAB broths were assayed for their effects on EHEC growth and on Caco-2 viability; thereafter, their biological properties were analysed in a co-culture system consisting of EHEC and Caco-2 cells. Caco-2 cells infected with EHEC significantly increased CXCL8 release, and decreased Trans-Epithelial Electrical Resistance (TEER), a barrier-integrity marker. Notably, when Caco-2 cells were treated with LAB broth enriched with E. sativa seed extract and thereafter infected, both CXCL8 expression and epithelial dysfunction reduced compared to in untreated cells. These results underline the beneficial effect of broths from LAB fermented with E. sativa seed extracts in gut barrier and inflammation after EHEC infection and reveal that these LAB broths can be used as functional bioactive compounds to regulate intestinal function.

Selective chemiluminescent TURN-ON quantitative bioassay and imaging of intracellular hydrogen peroxide in human living cells

Hydrogen peroxide is an unavoidable by-product of cell metabolism, but when it is not properly managed by the body it can lead to several pathologies (e.g., premature aging, cardiovascular and neurodegenerative diseases, cancer). Several methods have been proposed for the measurement of intracellular H₂O₂ but none of them has proven to be selective. We developed a rapid all-in-one chemiluminescent bioassay for the quantification of H₂O₂ in living cells with a low limit of detection (0.15 μM). The method relies on an adamantylidene-1,2-dioxetane lipophilic probe containing an arylboronate moiety; upon reaction with H₂O₂ the arylboronate moiety is converted to the correspondent phenol and the molecule decomposes leading to an excited-state fragment that emits light. The probe has been successfully employed for quantifying intracellular H₂O₂ in living human endothelial, colon and keratinocyte cells exposed to different pro-oxidant stimuli (i.e., menadione, phorbol myristate acetate and lipopolysaccharide). Imaging experiments clearly localize the chemiluminescence emission inside the cells. Treatment of cells with antioxidant molecules leads to a dose-dependent decrease of intracellular H₂O₂ levels. As a proof of concept, the bioassay has been used to measure the antioxidant activity of extracts from Brassica juncea wastes, which contain glucosinolates, isothiocyanates and other antioxidant molecules.

Estrogen-mediated protection against coronary heart disease: The role of the Notch pathway

Estrogen regulates a plethora of biological processes, under physiological and pathological conditions, by affecting key pathways involved in the regulation of cell proliferation, fate, survival and metabolism. The Notch receptors are mediators of communication between adjacent cells and are key determinants of cell fate during development and in postnatal life. Crosstalk between estrogen and the Notch pathway intervenes in many processes underlying the development and maintenance of the cardiovascular system. The identification of molecular mechanisms underlying the interaction between these types of endocrine and juxtacrine signaling are leading to a deeper understanding of physiological conditions regulated by these steroid hormones and, potentially, to novel therapeutic approaches to prevent pathologies linked to reduced levels of estrogen, such as coronary heart disease, and cardiotoxicity caused by hormone therapy for estrogen-receptor-positive breast cancer.

Heart rate reduction with ivabradine in the early phase of atherosclerosis is protective in the endothelium of ApoE-deficient mice

Ivabradine, a heart rate reducing agent, protects the vascular system by unidentified mechanisms. We sought to determine the effects of the treatment with ivabradine, started before plaque formation, on early transcriptional changes and endothelium lesions in regions of aorta subjected to disturbed blood flow. Six week-old apolipoprotein E-deficient (ApoE^-/-) mice, fed a low-fat diet, were treated with ivabradine to determine the effect on transcriptional changes (2-and 4-week treatment) and on lesions formation (19-week treatment) in the endothelium of the aortic arch. Microarrays analysis (60k probes) of endothelium-enriched RNA was carried out to detect changes in gene expression induced by treatment. Endothelium damage was assessed by en-face immunofluorescence staining for vascular endothelial (VE) cadherin. According to microarray analysis, 930 transcripts were affected by the treatment. We found downregulation of pro-apoptotic and pro-inflammatory genes, the majority of which are nuclear factor-κB (NF-κB)-and/or angiotensin II-regulated genes, and upregulation of anti-inflammatory genes. Many shear stress-responsive genes were affected by the treatment and the MAPK, Notch signalling and sterol metabolic processes were among the most significantly affected pathways. Consistently, we observed increased levels of Hes5, a Notch target gene, together with a reduction of endothelium damage, in the lower aortic arch of treated- compared with untreated- mice. We concluded that an early treatment with ivabradine protected the endothelium of the aortic arch of ApoE^-/- mice. Activation of the Notch signalling could be part of the mechanism underlying this protection.

Advanced biosensors for monitoring astronauts' health during long-duration space missions

Long-duration space missions pose important health concerns for astronauts, especially regarding the adverse effects of microgravity and exposure to high-energy cosmic rays. The long-term maintenance of crew health and performance mainly relies on prevention, early diagnoses, condition management, and medical interventions in situ. In-flight biosensor diagnostic devices and medical procedures must use few resources and operate in a microgravity environment, which complicates the collection and management of biological samples. Moreover, the biosensors must be certified for in-flight operation according to strict design and safety regulations. Herein, we report on the state of the art and recent advances in biosensing diagnostic instrumentation for monitoring astronauts' health during long-duration space missions, including portable and wearable biosensors. We discuss perspectives on new-format biosensors in autonomous space clinics. We also describe our own work in developing biosensing devices for non-invasively diagnosing space-related diseases, and how they are used in long-duration missions. Finally, we discuss the benefits of space exploration for Earth-based medicine.

Comparative study of the antioxidant and immunomodulant activities between yeast and lab fermented papaya

Background: Dietary supplements of Carica papaya Linn fermented with yeast using a biotechnological process have well recognized positive effects on immunological, hematological, inflammatory, and oxidative stress parameters, utilized as biomarkers of chronic and degenerative diseases. Although many natural products fermented with lactic acid bacteria (LAB) have shown beneficial effects on the immune system and on antioxidant defenses, formulations of papaya fermented with LAB have not yet been studied.Aims: The aims of this study were to investigate the immunomodulatory activity linked to the type of papaya fermentation (yeast vs LAB) in macrophages and to evaluate whether the type of fermentation differently modulates oxidative stress both in cell free system and in a model of embryonic brain cells.Methods: Cytotoxicity was evaluated through cell proliferation kinetic and lactate dehydrogenase release assays; immunomodulatory activity through the transcriptional activation of inducible nitric oxide synthase (iNOS) and Tumor Necrosis Factor α (TNFα) by qRT-PCR in RAW 264.7 macrophages; antioxidant capacity was assessed, in cell free system and in pheochromocytoma cells embryonic brain cells, by measuring the intracellular ROS levels through a fluorescent dye.Results: Our data showed that all the formulations studied are safe at low concentrations (3-6 mg/ml); the LAB- fermented formulations promoted the expression of iNOS and TNFα more efficiently than yeast-fermented papaya preparation (p <0.001). In a cell free system, the LAB-fermented formulation acted as mild scavengers of ROS while, in cells, both formulations didn’t show any significant effect.Conclusions: This study corroborates previous reports showing the efficacy of yeast fermented papaya as a potent immunostimulant and highlights the beneficial contribution of lactic bacteria fermentation.Keywords: papaya, lactic fermentation, immunostimulant activity, antioxidant activity

Estrogen receptor β-dependent Notch1 activation protects vascular endothelium against tumor necrosis factor α (TNFα)-induced apoptosis

Unlike age-matched men, premenopausal women benefit from cardiovascular protection. Estrogens protect against apoptosis of endothelial cells (ECs), one of the hallmarks of endothelial dysfunction leading to cardiovascular disorders, but the underlying molecular mechanisms remain poorly understood. The inflammatory cytokine TNFα causes EC apoptosis while dysregulating the Notch pathway, a major contributor to EC survival. We have previously reported that 17β-estradiol (E2) treatment activates Notch signaling in ECs. Here, we sought to assess whether in TNFα-induced inflammation Notch is involved in E2-mediated protection of the endothelium. We treated human umbilical vein endothelial cells (HUVECs) with E2, TNFα, or both and found that E2 counteracts TNFα-induced apoptosis. When Notch1 was inhibited, this E2-mediated protection was not observed, whereas ectopic overexpression of Notch1 diminished TNFα-induced apoptosis. Moreover, TNFα reduced the levels of active Notch1 protein, which were partially restored by E2 treatment. Moreover, siRNA-mediated knockdown of estrogen receptor β (ERβ), but not ERα, abolished the effect of E2 on apoptosis. Additionally, the E2-mediated regulation of the levels of active Notch1 was abrogated after silencing ERβ. In summary, our results indicate that E2 requires active Notch1 through a mechanism involving ERβ to protect the endothelium in TNFα-induced inflammation. These findings could be relevant for assessing the efficacy and applicability of menopausal hormone treatment, because they may indicate that in women with impaired Notch signaling, hormone therapy might not effectively protect the endothelium.

Effect of apple polyphenols on vascular oxidative stress and endothelium function: a translational study

SCOPE

We aimed examining apple polyphenols' effect on uricemia and endothelial function in a sample of overweight subjects.

METHODS AND RESULTS

This was a two-phased study. In vitro experiment aimed to evaluate apple polyphenols' ability to lower uric acid in comparison with allopurinol. In vivo study consisted in a randomized, double-blind, parallel placebo-controlled clinical trial involving 62 overweight volunteers with suboptimal values of fasting plasma glucose (100 mg/dL≤FPG≤125 mg/dL), randomized to 300 mg apple polyphenols or placebo for 8 weeks. Apple polyphenols extract inhibited xanthine oxidase activity, with an IC50 = 130 ± 30 ng/mL; reducing uric acid production with an IC50 = 154 ± 28 ng/mL. During the trial, after the first 4 weeks of treatment, FPG decreased in the active treated group (-6.1%, p < 0.05), while no significant changes were observed regarding the other hematochemistry parameters. After 4 more weeks of treatment, active-treated patients had an improvement in FPG compared to baseline (-10.3%, p < 0,001) and the placebo group (p < 0,001). Uric acid (-14.0%, p < 0.05 versus baseline; p < 0.05 versus placebo) and endothelial reactivity (0.24±0.09, p = 0.009 versus baseline; p < 0.05 versus placebo) significantly improved too.

CONCLUSION

In vivo, apple polyphenols extract has a positive effect on vascular oxidative stress and endothelium function and reduce FPG and uric acid by inhibiting xanthine oxidase, as our In vitro experiment attests.

Novel role of the nutraceutical bioactive compound berberine in lectin-like OxLDL receptor 1-mediated endothelial dysfunction in comparison to lovastatin

BACKGROUND AND AIMS

Oxidized LDL (oxLDL) or pro-inflammatory stimuli lead to increased oxidative stress linked to endothelial dysfunction and atherosclerosis. The oxLDL receptor-1 (LOX1) is elevated within atheromas and cholesterol-lowering statins inhibit LOX1 expression. Berberine (BBR), an alkaloid extracted from plants of gender Berberis, has lipid-lowering and anti-inflammatory activity. However, its role in regulating LOX1-mediated signaling is still unknown. The aim of this study was to investigate the effect of BBR on oxLDL- and TNFα-induced endothelial dysfunction in human umbilical vein endothelial cells (HUVECs) and to compare it with that of lovastatin (LOVA).

METHODS AND RESULTS

Cytotoxicity was determined by lactate dehydrogenase assay. Antioxidant capacity was measured with chemiluminescent and fluorescent method and intracellular ROS levels through a fluorescent dye. Gene and protein expression levels were assayed by qRT-PCR and western blot, respectively. HUVECs exposure to oxLDL (30 μg/ml) or TNFα (10 ng/ml) for 24 h led to a significant increase in LOX1 expression, effect abrogated by BBR (5 μM) and LOVA (5 μM). BBR but not LOVA treatment abolished the TNFα-induced cytotoxicity and restored the activation of Akt signaling. In spite of a low direct antioxidant capacity, both compounds reduced intracellular ROS levels generated by treatment of TNFα but only BBR inhibited NOX2 expression, MAPK/Erk1/2 signaling and subsequent NF-κB target genes VCAM and ICAM expression, induced by TNFα.

CONCLUSIONS

These findings demonstrated for the first time that BBR could prevent the oxLDL and TNFα - induced LOX1 expression and oxidative stress, key events that lead to NOX, MAPK/Erk1/2 and NF-κB activation linked to endothelial dysfunction.

CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE

Berberine (PubChem CID: 2353); Lovastatin (PubChem CID: 53232).

Distinct gene expression profiles associated with Notch ligands Delta-like 4 and Jagged1 in plaque material from peripheral artery disease patients: a pilot study

Background

The lack of early diagnosis, progression markers and effective pharmacological treatment has dramatic unfavourable effects on clinical outcomes in patients with peripheral artery disease (PAD). Addressing these issues will require dissecting the molecular mechanisms underlying this disease. We sought to characterize the Notch signaling and atherosclerosis relevant markers in lesions from femoral arteries of symptomatic PAD patients.

Methods

Plaque material from the common femoral, superficial femoral or popliteal arteries of 20 patients was removed by directional atherectomy. RNA was obtained from 9 out of 20 samples and analysed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR).

Results

We detected expression of Notch ligands Delta-like 4 (Dll4) and Jagged1 (Jag1), of Notch target genes Hes1, Hey1, Hey2, HeyL and of markers of plaque inflammation and stability such as vascular cell adhesion molecule 1 (VCAM1), smooth muscle 22 (SM22), cyclooxygenase 2 (COX2), Bcl2, CD68 and miRNAs 21-5p, 125a-5p, 126-5p,146-5p, 155-5p, 424-5p. We found an “inflamed plaque” gene expression profile characterized by high Dll4 associated to medium/high CD68, COX2, VCAM1, Hes1, miR126-5p, miR146a-5p, miR155-5p, miR424-5p and low Jag1, SM22, Bcl2, Hey2, HeyL, miR125a-5p (2/9 patients) and a “stable plaque” profile characterized by high Jag1 associated to medium/high Hey2, HeyL, SM22, Bcl2, miR125a and low Dll4, CD68, COX2, VCAM1, miR126-5p, miR146a-5p, miR155-5p, miR424-5p (3/9 patients). The remaining patients (4/9) showed a plaque profile with intermediate characteristics.

Conclusions

This study reveals the existence of a gene signature associated to Notch activation by specific ligands that could be predictive of PAD progression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-017-1199-3) contains supplementary material, which is available to authorized users.

Fructose Intake, Serum Uric Acid, and Cardiometabolic Disorders: A Critical Review

There is a direct relationship between fructose intake and serum levels of uric acid (UA), which is the final product of purine metabolism. Recent preclinical and clinical evidence suggests that chronic hyperuricemia is an independent risk factor for hypertension, metabolic syndrome, and cardiovascular disease. It is probably also an independent risk factor for chronic kidney disease, Type 2 diabetes, and cognitive decline. These relationships have been observed for high serum UA levels (>5.5 mg/dL in women and >6 mg/dL in men), but also for normal to high serum UA levels (5-6 mg/dL). In this regard, blood UA levels are much higher in industrialized countries than in the rest of the world. Xanthine-oxidase inhibitors can reduce UA and seem to minimize its negative effects on vascular health. Other dietary and pathophysiological factors are also related to UA production. However, the role of fructose-derived UA in the pathogenesis of cardiometabolic disorders has not yet been fully clarified. Here, we critically review recent research on the biochemistry of UA production, the relationship between fructose intake and UA production, and how this relationship is linked to cardiometabolic disorders.

Berberine: New Insights from Pharmacological Aspects to Clinical Evidences in the Management of Metabolic Disorders

Berberine is a quaternary ammonium salt from the protoberberine group of isoquinoline alkaloids found in such plants as gender Berberis. Berberine is recognised to improve glucose and lipid metabolism disorders and preliminary clinical evidences suggest the ability of berberine to reduce endothelial inflammation improving vascular health, even in patients already affected by cardiovascular diseases, suggesting a possible interesting role of berberine and its metabolites in clinical practice. However, its physicochemical properties, pharmacokinetic, and metabolism are not fully elucidated and contradictory data have been reported. This review provides a summary regarding the pharmacological and biological features of berberine, with a focus on berberine as well as their pharmacologically active metabolites and the different mechanisms underlying their activities in order to clarify the correct use of berberine supplementation, alone or in association with other nutraceuticals, for the management of metabolic disorders associated to increased cardiovascular disease risk. A particular attention has also been given to the available clinical trials assessing its short- and middle- term use tolerability, safety and efficacy in various conditions, such as dyslipidaemia, impaired fasting glucose, metabolic syndrome and type 2 diabetes.

A new sensitive and quantitative chemiluminescent assay to monitor intracellular xanthine oxidase activity for rapid screening of inhibitors in living endothelial cells

Xanthine oxidase (XO) is an important enzyme, expressed at high levels in the vasculature in endothelial cells, that catalyzes the hydroxylation of hypoxanthine to xanthine and xanthine to uric acid. Excessive production of uric acid results in hyperuricemia linked to gout and cardiovascular diseases. Testing inhibition of XO is important for detection of potentially effective drugs or natural products that could be used to treat diseases caused by increased XO activity. In the present study, for the first time, we developed an in vitro chemiluminescent bioassay to determine XO activity in living endothelial cells and the IC50 value of oxypurinol, the active metabolite of the inhibitor drug allopurinol. Intracellular XO activity was measured in less than 20 min with a luminol/catalyst-based chemiluminescence assay able to measure XO with a limit of 0.4 μU/mL. Oxypurinol addition to 5 × 10³ cells (ranging from 5.0 to 0.0 μM) caused a linear decrease in XO activity, with an IC50 of 1.0 ± 0.5 μM. The detection system developed was low-cost, rapid, reproducible, and easily miniaturizable so suitable to be used on small quantities of cells.

Serum From Advanced Heart Failure Patients Promotes Angiogenic Sprouting and Affects the Notch Pathway in Human Endothelial Cells

It is unknown whether components present in heart failure (HF) patients' serum provide an angiogenic stimulus. We sought to determine whether serum from HF patients affects angiogenesis and its major modulator, the Notch pathway, in human umbilical vein endothelial cells (HUVECs). In cells treated with serum from healthy subjects or from patients at different HF stage we determined: (1) Sprouting angiogenesis, by measuring cells network (closed tubes) in collagen gel. (2) Protein levels of Notch receptors 1, 2, 4, and ligands Jagged1, Delta-like4. We found a higher number of closed tubes in HUVECs treated with advanced HF patients serum in comparison with cells treated with serum from mild HF patients or controls. Furthermore, as indicated by the reduction of the active form of Notch4 (N4IC) and of Jagged1, advanced HF patients serum inhibited Notch signalling in HUVECs in comparison with mild HF patients' serum and controls. The circulating levels of NT-proBNP (N-terminal of the pro-hormone brain natriuretic peptide), a marker for the detection and evalutation of HF, were positively correlated with the number of closed tubes (r = 0.485) and negatively with Notch4IC and Jagged1 levels in sera-treated cells (r = -0.526 and r = -0.604, respectively). In conclusion, we found that sera from advanced HF patients promote sprouting angiogenesis and dysregulate Notch signaling in HUVECs. Our study provides in vitro evidence of an angiogenic stimulus arising during HF progression and suggests a role for the Notch pathway in it. J. Cell. Physiol. 231: 2700-2710, 2016. © 2016 Wiley Periodicals, Inc.

Characterization of Notch Signaling During Osteogenic Differentiation in Human Osteosarcoma Cell Line MG63

Osteogenic differentiation is a multi-step process controlled by a complex molecular framework. Notch is an evolutionarily conserved intercellular signaling pathway playing a prominent role in cell fate and differentiation, although the mechanisms by which this pathway regulates osteogenesis remain controversial. This study aimed to investigate, in vitro, the involvement of Notch pathway during all the developmental stages of osteogenic differentiation in human osteosarcoma cell line MG63. Cells were cultured in basal condition (control) and in osteoinductive medium (OM). Notch inhibitors were also added in OM to block Notch pathway. During osteogenic differentiation, early (alkaline phosphatase activity and collagen type I) and late osteogenic markers (osteocalcin levels and matrix mineralization), as well as the gene expression of the main osteogenic transcription factors (Runx2, Osterix, and Dlx5) increased. Time dependent changes in the expression of specific Notch receptors were identified in OM versus control with a significant reduction in the expression of Notch1 and Notch3 receptors in the early phase of differentiation, and an increase of Notch2 and Notch4 receptors in the late phase. Among Notch nuclear target genes, Hey1 expression was significantly higher in OM than control, while Hes5 expression decreased. Osteogenic markers were reduced and Hey1 was significantly inhibited by Notch inhibitors, suggesting a role for Notch through the canonical pathway. In conclusion, Notch pathway might be involved with a dual role in osteogenesis of MG63, through the activation of Notch2, Notch4, and Hey1, inducing osteoblast differentiation and the depression of Notch1, Notch3, and Hes5, maintaining an undifferentiated status. J. Cell. Physiol. 231: 2652-2663, 2016. © 2016 Wiley Periodicals, Inc.

The role of notch in the cardiovascular system: potential adverse effects of investigational notch inhibitors

Targeting the Notch pathway is a new promising therapeutic approach for cancer patients. Inhibition of Notch is effective in the oncology setting because it causes a reduction of highly proliferative tumor cells and it inhibits survival of cancer stem cells, which are considered responsible for tumor recurrence and metastasis. Additionally, since Delta-like ligand 4 (Dll4)-activated Notch signaling is a major modulator of angiogenesis, anti-Dll4 agents are being investigated to reduce vascularization of the tumor. Notch plays a major role in the heart during the development and, after birth, in response to cardiac damage. Therefore, agents used to inhibit Notch in the tumors (gamma secretase inhibitors and anti-Dll4 agents) could potentially affect myocardial repair. The past experience with trastuzumab and other tyrosine kinase inhibitors used for cancer therapy demonstrates that the possible cardiotoxicity of agents targeting shared pathways between cancer and heart and the vasculature should be considered. To date, Notch inhibition in cancer patients has resulted only in mild gastrointestinal toxicity. Little is known about the potential long-term cardiotoxicity associated to Notch inhibition in cancer patients. In this review, we will focus on mechanisms through which inhibition of Notch signaling could lead to cardiomyocytes and endothelial dysfunctions. These adverse effects could contrast with the benefits of therapeutic responses in cancer cells during times of increased cardiac stress and/or in the presence of cardiovascular risk factor.

Specific aquaporins facilitate Nox-produced hydrogen peroxide transport through plasma membrane in leukaemia cells

In the last decade, the generation and the role of reactive oxygen species (ROS), particularly hydrogen peroxide, in cell signalling transduction pathways have been intensively studied, and it is now clear that an increase of ROS level affects cellular growth and proliferation pathways related to cancer development. Hydrogen peroxide (H2O2) has been long thought to permeate biological membranes by simple diffusion since recent evidence challenged this notion disclosing the role of aquaporin water channels (AQP) in mediating H2O2 transport across plasma membranes. We previously demonstrated that NAD(P)H oxidase (Nox)-generated ROS sustain glucose uptake and cellular proliferation in leukaemia cells. The aim of this study was to assess whether specific AQP isoforms can channel Nox-produced H2O2 across the plasma membrane of leukaemia cells affecting downstream pathways linked to cell proliferation. In this work, we demonstrate that AQP inhibition caused a decrease in intracellular ROS accumulation in leukaemia cells both when H2O2 was produced by Nox enzymes and when it was exogenously added. Furthermore, AQP8 overexpression or silencing resulted to modulate VEGF capacity of triggering an H2O2 intracellular level increase or decrease, respectively. Finally, we report that AQP8 is capable of increasing H2O2-induced phosphorylation of both PI3K and p38 MAPK and that AQP8 expression affected positively cell proliferation. Taken together, the results here reported indicate that AQP8 is able to modulate H2O2 transport through the plasma membrane affecting redox signalling linked to leukaemia cell proliferation.

The role of Notch pathway in cardiovascular diseases

The recent increase in human lifespan, coupled with unhealthy diets and lifestyles have led to an unprecedented increase in cardiovascular diseases. Even in the presence of a wide range of therapeutic options with variable efficacy, mortality due to heart failure is still high and there is a need to identify new therapeutic targets. Genetic and in vitro studies have implicated the Notch signalling in the development and maintenance of the cardiovascular system through a direct effect on biological functions of vascular cells (endothelial and vascular smooth muscle cells) and cardiomyocytes. Notch signalling is also involved in the modulation of inflammation, which plays a major role in causing and exacerbating cardiovascular diseases. The Notch pathway could represent a new therapeutic target for the treatment of cardiovascular diseases.

17β-estradiol enhances signalling mediated by VEGF-A-delta-like ligand 4-notch1 axis in human endothelial cells

Estrogens play a protective role in coronary artery disease. The mechanisms of action are still poorly understood, although a role for estrogens in stimulation of angiogenesis has been suggested. In several cell types, estrogens modulate the Notch pathway, which is involved in controlling angiogenesis downstream of vascular endothelial growth factor A (VEGF-A). The goal of our study was to establish whether estrogens modulate Notch activity in endothelial cells and the possible consequences on angiogenesis. Human umbilical vein endothelial cells (HUVECs) were treated with 17β-estradiol (E2) and the effects on Notch signalling were evaluated. E2 increased Notch1 processing as indicated by i) decreased levels of Notch1 transmembrane subunit ii) increased amount of Notch1 in nuclei iii) unaffected level of mRNA. Similarly, E2 increased the levels of the active form of Notch4 without altering Notch4 mRNA. Conversely, protein and mRNA levels of Notch2 were both reduced suggesting transcriptional repression of Notch2 by E2. Under conditions where Notch was activated by upregulation of Delta-like ligand 4 (Dll4) following VEGF-A treatment, E2 caused a further increase of the active form of Notch1, of the number of cells with nuclear Notch1 and of Hey2 mRNA. Estrogen receptor antagonist ICI 182.780 antagonized these effects suggesting that E2 modulation of Notch1 is mediated by estrogen receptors. E2 treatment abolished the increase in endothelial cells sprouting caused by Notch inhibition in a tube formation assay on 3D Matrigel and in mouse aortic ring explants. In conclusion, E2 affects several Notch pathway components in HUVECs, leading to an activation of the VEGF-A-Dll4-Notch1 axis and to a modulation of vascular branching when Notch signalling is inhibited. These results contribute to our understanding of the molecular mechanisms of cardiovascular protection exerted by estrogens by uncovering a novel role of E2 in the Notch signalling-mediated modulation of angiogenesis.

Effect of plasma membrane cholesterol depletion on glucose transport regulation in leukemia cells

GLUT1 is the predominant glucose transporter in leukemia cells, and the modulation of glucose transport activity by cytokines, oncogenes or metabolic stresses is essential for their survival and proliferation. However, the molecular mechanisms allowing to control GLUT1 trafficking and degradation are still under debate. In this study we investigated whether plasma membrane cholesterol depletion plays a role in glucose transport activity in M07e cells, a human megakaryocytic leukemia line. To this purpose, the effect of cholesterol depletion by methyl-β-cyclodextrin (MBCD) on both GLUT1 activity and trafficking was compared to that of the cytokine Stem Cell Factor (SCF). Results show that, like SCF, MBCD led to an increased glucose transport rate and caused a subcellular redistribution of GLUT1, recruiting intracellular transporter molecules to the plasma membrane. Due to the role of caveolae/lipid rafts in GLUT1 stimulation in response to many stimuli, we have also investigated the GLUT1 distribution along the fractions obtained after non ionic detergent treatment and density gradient centrifugation, which was only slightly changed upon MBCD treatment. The data suggest that MBCD exerts its action via a cholesterol-dependent mechanism that ultimately results in augmented GLUT1 translocation. Moreover, cholesterol depletion triggers GLUT1 translocation without the involvement of c-kit signalling pathway, in fact MBCD effect does not involve Akt and PLCγ phosphorylation. These data, together with the observation that the combined MBCD/SCF cell treatment caused an additive effect on glucose uptake, suggest that the action of SCF and MBCD may proceed through two distinct mechanisms, the former following a signalling pathway, and the latter possibly involving a novel cholesterol dependent mechanism.

Novel role of p66Shc in ROS-dependent VEGF signaling and angiogenesis in endothelial cells

p66Shc, a longevity adaptor protein, is demonstrated as a key regulator of reactive oxygen species (ROS) metabolism involved in aging and cardiovascular diseases. Vascular endothelial growth factor (VEGF) stimulates endothelial cell (EC) migration and proliferation primarily through the VEGF receptor-2 (VEGFR2). We have shown that ROS derived from Rac1-dependent NADPH oxidase are involved in VEGFR2 autophosphorylation and angiogenic-related responses in ECs. However, a role of p66Shc in VEGF signaling and physiological responses in ECs is unknown. Here we show that VEGF promotes p66Shc phosphorylation at Ser36 through the JNK/ERK or PKC pathway as well as Rac1 binding to a nonphosphorylated form of p66Shc in ECs. Depletion of endogenous p66Shc with short interfering RNA inhibits VEGF-induced Rac1 activity and ROS production. Fractionation of caveolin-enriched lipid raft demonstrates that p66Shc plays a critical role in VEGFR2 phosphorylation in caveolae/lipid rafts as well as downstream p38MAP kinase activation. This in turn stimulates VEGF-induced EC migration, proliferation, and capillary-like tube formation. These studies uncover a novel role of p66Shc as a positive regulator for ROS-dependent VEGFR2 signaling linked to angiogenesis in ECs and suggest p66Shc as a potential therapeutic target for various angiogenesis-dependent diseases.

NAD(P)H oxidase isoform Nox2 plays a prosurvival role in human leukaemia cells

The mechanism involved in the prosurvival effect of interleukin-3 on the human acute myeloid leukaemia cell line M07e is investigated. A decrease in intracellular reactive oxygen species (ROS) content, glucose transport activity and cell survival was observed in the presence of inhibitors of plasma membrane ROS sources, such as diphenylene iodonium and apocynin, and by small interference RNA for Nox2. Moreover, IL-3 incubation stimulated the synthesis of Nox2 cytosolic sub-unit p47phox and glucose transporter Glut1. Thus, the inhibition of ROS generation by Nox inhibitors stimulated apoptosis showing that ROS production, induced by IL-3 via Nox2, protects leukaemic cells from cell death. Also incubation with receptor tyrosine kinase inhibitors, such as anti-leukaemic drugs blocking the stem cell factor receptor (c-kit), showed similar effects, hinting that IL-3 transmodulates c-kit phosphorylation. These mechanisms may play an important role in acute myeloid leukaemia treatment, representing a novel therapeutic target.

VEGF-induced ROS generation from NAD(P)H oxidases protects human leukemic cells from apoptosis

Vascular endothelial growth factor (VEGF) and reactive oxygen species (ROS) play critical roles in vascular pathophysiology and in hematological malignancies. VEGF is supposed to utilize ROS as messenger intermediates downstream of the VEGF receptor-2. NAD(P)H oxidase (Nox) family is a major source of cellular ROS and is implicated in increased ROS production in tumor cells. We previously demonstrated that B1647 cells, a human leukemic cell line, express Nox2 and Nox4, both at mRNA and protein level. We suggest here that the VEGF-induced increase in ROS can be related to Nox2 and Nox4 activities. Nox-derived ROS are involved in early signaling events such as the autophosphorylation of VEGF receptor-2, and in the modulation of glucose uptake, a cellular activity strictly bound to VEGF-induced leukemic cell proliferation, as shown by experiments with antioxidants and Nox inhibitors and siRNA. Nox-generated ROS are required to sustain B1647 cell viability and proliferation; in fact, antioxidants such as EUK-134 or Nox inhibitors and siRNA direct cells to apoptotic cell death, suggesting that manipulation of cellular Nox2 and Nox4 could affect survival of leukemic cells.

Inhibition of trans-plasma membrane electron transport: a potential anti-leukemic strategy

The recently demonstrated reliance of glycolytic cancer cells on trans-plasma membrane electron transport (tPMET) for survival raises the question of its suitability as a target for anticancer drug development. In this study, the effects of several new and known compounds on proliferation, tPMET activity and NAD(P)H intrinsic fluorescence in human myelogenous leukemic cell lines were investigated. The whole data confirm the importance of tPMET in leukemic cell survival and suggest this activity as a new potential anti-leukemic target.