Pro-angiogenic Role of Insulin: From Physiology to Pathology

Insulin-Loaded Chitosan-Cellulose-Derivative Hydrogels: In Vitro Permeation of Hormone through Strat-M® Membrane and Rheological and Textural Analysis

This work is part of the current research trend to develop a hydrogel carrier of insulin to promote wound healing. Topically applied insulin promotes keratinocyte proliferation and migration, increases collagen synthesis, reduces inflammation and oxidative stress, and exhibits antimicrobial activity. The aim of this study was to design an insulin hydrogel matrix based on selected cellulose derivatives (methylcellulose, hydroxyethylcellulose, and hydroxypropylmethylcellulose) and chitosan. Rheological parameters of the formulations were evaluated using rotational rheometry and an oscillation test. Textural tests were performed. In vitro pharmaceutical insulin availability studies were carried out using the innovative Strat-M® membrane to imitate the skin barrier. It was found that the pharmaceutical formulation of insulin based on chitosan and methylcellulose showed an acceptable balance between rheological and textural parameters and ease of application. The API was released from the carrier in a prolonged manner, eliminating the need to apply the formulation several times per day. The developed hydrogel shows potential for use in clinical practice.

Correlation between tooth decay and insulin resistance in normal weight males prompts a role for myo-inositol as a regenerative factor in dentistry and oral surgery: a feasibility study

Background

In an era of precision and stratified medicine, homogeneity in population-based cohorts, stringent causative entry, and pattern analysis of datasets are key elements to investigate medical treatments. Adhering to these principles, we collected in vivo and in vitro data pointing to an insulin-sensitizing/insulin-mimetic effect of myo-inositol (MYO) relevant to cell regeneration in dentistry and oral surgery. Confirmation of this possibility was obtained by in silico analysis of the relation between in vivo and in vitro results (the so-called bed-to-benchside reverse translational approach).

Results

Fourteen subjects over the 266 screened were young adult, normal weight, euglycemic, sedentary males having normal appetite, free diet, with a regular three-times-a-day eating schedule, standard dental hygiene, and negligible malocclusion/enamel defects. Occlusal caries were detected by fluorescence videoscanning, whereas body composition and energy balance were estimated with plicometry, predictive equations, and handgrip. Statistically significant correlations (Pearson r coefficient) were found between the number of occlusal caries and anthropometric indexes predicting insulin resistance (IR) in relation to the abdominal/visceral fat mass, fat-free mass, muscular strength, and energy expenditure adjusted to the fat and muscle stores. This indicated a role for IR in affecting dentin reparative processes. Consistently, in vitro administration of MYO to HUVEC and Swiss NIH3T3 cells in concentrations corresponding to those administered in vivo to reduce IR resulted in statistically significant cell replication (ANOVA/Turkey tests), suggesting that MYO has the potential to counteract inhibitory effects of IR on dental vascular and stromal cells turnover. Finally, in in silico experiments, quantitative evaluation (WOE and information value) of a bioinformatic Clinical Outcome Pathway confirmed that in vitro trophic effects of MYO could be transferred in vivo with high predictability, providing robust credence of its efficacy for oral health.

Conclusion

Our reverse bed-to-benchside data indicate that MYO might antagonize the detrimental effects of IR on tooth decay. This provides feasibility for clinical studies on MYO as a regenerative factor in dentistry and oral surgery, including dysmetabolic/aging conditions, bone reconstruction in oral destructive/necrotic disorders, dental implants, and for empowering the efficacy of a number of tissue engineering methodologies in dentistry and oral surgery.

Microfluidic vascular formation model for assessing angiogenic capacities of single islets

Pancreatic islet transplantation presents a promising therapy for individuals suffering from type 1 diabetes. To maintain the function of transplanted islets in vivo, it is imperative to induce angiogenesis. However, the mechanisms underlying angiogenesis triggered by islets remain unclear. In this study, we introduced a microphysiological system to study the angiogenic capacity and dynamics of individual islets. The system, which features an open-top structure, uniquely facilitates the inoculation of islets and the longitudinal observation of vascular formation in in vivo like microenvironment with islet-endothelial cell communication. By leveraging our system, we discovered notable islet-islet heterogeneity in the angiogenic capacity. Transcriptomic analysis of the vascularized islets revealed that islets with high angiogenic capacity exhibited upregulation of genes related to insulin secretion and downregulation of genes related to angiogenesis and fibroblasts. In conclusion, our microfluidic approach is effective in characterizing the vascular formation of individual islets and holds great promise for elucidating the angiogenic mechanisms that enhance islet transplantation therapy.

Antidiabetic Drugs in Breast Cancer Patients

Diabetes is one of the leading chronic conditions worldwide, and breast cancer is the most prevalent cancer in women worldwide. The linkage between diabetes and its ability to increase the risk of breast cancer should always be analyzed in patients. This review focuses on the impact of antihyperglycemic therapy in breast cancer patients. Patients with diabetes have a higher risk of developing cancer than the general population. Moreover, diabetes patients have a higher incidence and mortality of breast cancer. In this review, we describe the influence of antidiabetic drugs from insulin and metformin to the current and emerging therapies, incretins and SGLT-2 inhibitors, on breast cancer prognosis. We also emphasize the role of obesity and the metastasis process in breast cancer patients who are treated with antidiabetic drugs.

Mechanisms of Diabetic Nephropathy Not Mediated by Hyperglycemia

Diabetes mellitus (DM) is characterized by the appearance of progressive kidney damage, which may progress to end-stage kidney disease. The control of hyperglycemia is usually not sufficient to halt this progression. The kidney damage is quantitatively and qualitatively different in the two forms of diabetes; the typical nodular fibrosis (Kimmelstiel Wilson nodules) appears mostly in type 1 DM, whereas glomerulomegaly is primarily present in type 2 obese DM. An analysis of the different metabolites and hormones in type 1 and type 2 DM and their differential pharmacological treatments might be helpful to advance the hypotheses on the different histopathological patterns of the kidneys and their responses to sodium/glucose transporter type 2 inhibitors (SGLT2i).

Ketosis Suppression and Ageing (KetoSAge): The Effects of Suppressing Ketosis in Long Term Keto-Adapted Non-Athletic Females

Most studies on ketosis have focused on short-term effects, male athletes, or weight loss. Hereby, we studied the effects of short-term ketosis suppression in healthy women on long-standing ketosis. Ten lean (BMI 20.5 ± 1.4), metabolically healthy, pre-menopausal women (age 32.3 ± 8.9) maintaining nutritional ketosis (NK) for > 1 year (3.9 years ± 2.3) underwent three 21-day phases: nutritional ketosis (NK; P1), suppressed ketosis (SuK; P2), and returned to NK (P3). Adherence to each phase was confirmed with daily capillary D-beta-hydroxybutyrate (BHB) tests (P1 = 1.9 ± 0.7; P2 = 0.1 ± 0.1; and P3 = 1.9 ± 0.6 pmol/L). Ageing biomarkers and anthropometrics were evaluated at the end of each phase. Ketosis suppression significantly increased: insulin, 1.78-fold from 33.60 (± 8.63) to 59.80 (± 14.69) pmol/L (p = 0.0002); IGF1, 1.83-fold from 149.30 (± 32.96) to 273.40 (± 85.66) µg/L (p = 0.0045); glucose, 1.17-fold from 78.6 (± 9.5) to 92.2 (± 10.6) mg/dL (p = 0.0088); respiratory quotient (RQ), 1.09-fold 0.66 (± 0.05) to 0.72 (± 0.06; p = 0.0427); and PAI-1, 13.34 (± 6.85) to 16.69 (± 6.26) ng/mL (p = 0.0428). VEGF, EGF, and monocyte chemotactic protein also significantly increased, indicating a pro-inflammatory shift. Sustained ketosis showed no adverse health effects, and may mitigate hyperinsulinemia without impairing metabolic flexibility in metabolically healthy women.

Derivation of Human Extraembryonic Mesoderm-like Cells from Primitive Endoderm

In vitro modeling of human peri-gastrulation development is a valuable tool for understanding embryogenetic mechanisms. The extraembryonic mesoderm (ExM) is crucial in supporting embryonic development by forming tissues such as the yolk sac, allantois, and chorionic villi. However, the origin of human ExM remains only partially understood. While evidence suggests a primitive endoderm (PrE) origin based on morphological findings, current in vitro models use epiblast-like cells. To address this gap, we developed a protocol to generate ExM-like cells from PrE-like cell line called naïve extraembryonic endoderm (nEnd). We identified the ExM-like cells by specific markers (LUM and ANXA1). Moreover, these in vitro-produced ExM cells displayed angiogenic potential on a soft matrix, mirroring their physiological role in vasculogenesis. By integrating single-cell RNA sequencing (scRNAseq) data, we found that the ExM-like cells clustered with the LUM/ANXA1-rich cell populations of the gastrulating embryo, indicating similarity between in vitro and ex utero cell populations. This study confirms the derivation of ExM from PrE and establishes a cell culture system that can be utilized to investigate ExM during human peri-gastrulation development, both in monolayer cultures and more complex models.

Single-nucleus RNA sequencing in ischemic cardiomyopathy reveals common transcriptional profile underlying end-stage heart failure

Ischemic cardiomyopathy (ICM) is the leading cause of heart failure worldwide, yet the cellular and molecular signature of this disease is largely unclear. Using single-nucleus RNA sequencing (snRNA-seq) and integrated computational analyses, we profile the transcriptomes of over 99,000 human cardiac nuclei from the non-infarct region of the left ventricle of 7 ICM transplant recipients and 8 non-failing (NF) controls. We find the cellular composition of the ischemic heart is significantly altered, with decreased cardiomyocytes and increased proportions of lymphatic, angiogenic, and arterial endothelial cells in patients with ICM. We show that there is increased LAMININ signaling from endothelial cells to other cell types in ICM compared with NF. Finally, we find that the transcriptional changes that occur in ICM are similar to those in hypertrophic and dilated cardiomyopathies and that the mining of these combined datasets can identify druggable genes that could be used to target end-stage heart failure.

Endothelial cell dysfunction: Implications for the pathogenesis of peripheral artery disease

Peripheral artery disease (PAD) is caused by occluded or narrowed arteries that reduce blood flow to the lower limbs. The treatment focuses on lifestyle changes, management of modifiable risk factors and vascular surgery. In this review we focus on how Endothelial Cell (EC) dysfunction contributes to PAD pathophysiology and describe the largely untapped potential of correcting endothelial dysfunction. Moreover, we describe current treatments and clinical trials which improve EC dysfunction and offer insights into where future research efforts could be made. Endothelial dysfunction could represent a target for PAD therapy.

Identification Markers of Carotid Vulnerable Plaques: An Update

Vulnerable plaques have been a hot topic in the field of stroke and carotid atherosclerosis. Currently, risk stratification and intervention of carotid plaques are guided by the degree of luminal stenosis. Recently, it has been recognized that the vulnerability of plaques may contribute to the risk of stroke. Some classical interventions, such as carotid endarterectomy, significantly reduce the risk of stroke in symptomatic patients with severe carotid stenosis, while for asymptomatic patients, clinically silent plaques with rupture tendency may expose them to the risk of cerebrovascular events. Early identification of vulnerable plaques contributes to lowering the risk of cerebrovascular events. Previously, the identification of vulnerable plaques was commonly based on imaging technologies at the macroscopic level. Recently, some microscopic molecules pertaining to vulnerable plaques have emerged, and could be potential biomarkers or therapeutic targets. This review aimed to update the previous summarization of vulnerable plaques and identify vulnerable plaques at the microscopic and macroscopic levels.

Targeting Pancreatic Islet NLRP3 Improves Islet Graft Revascularization

Hypoxia-induced islet cell death, caused by an insufficient revascularization of the grafts, is a major obstacle for successful pancreatic islet transplantation. Recently, it has been reported that the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is expressed in pancreatic islets and that its loss protects against hypoxia-induced cell death. Therefore, we hypothesized that the inhibition of NLRP3 in islets improves the survival and endocrine function of the grafts. The transplantation of Nlrp3-/- islets or wild-type (WT) islets exposed to the NLRP3 inhibitor CY-09 into mouse dorsal skinfold chambers resulted in an improved revascularization compared with controls. An increased insulin release after NLRP3 inhibition caused the enhanced angiogenic response. Moreover, the inhibition of NLRP3 in hypoxic β-cells triggered insulin gene expression by inducing the shuttling of MafA and pancreatic and duodenal homeobox-1 into the nucleus. This was mediated by a reduced interaction of NLRP3 with the thioredoxin-interacting protein (TXNIP). Transplantation of Nlrp3-/- islets or WT islets exposed to CY-09 under the kidney capsule of diabetic mice markedly improved the restoration of normoglycemia. These findings indicate that the inhibition of NLRP3 in isolated islets represents a promising therapeutic strategy to improve engraftment and function of the islets.

Identification and characterization of stem cell secretome-based recombinant proteins for wound healing applications

Stem cells have been introduced as a promising therapy for acute and chronic wounds, including burn injuries. The effects of stem cell-based wound therapies are believed to result from the secreted bioactive molecules produced by stem cells. Therefore, treatments using stem cell-derived conditioned medium (CM) (referred to as secretome) have been proposed as an alternative option for wound care. However, safety and regulatory concerns exist due to the uncharacterized biochemical content and variability across different batches of CM samples. This study presents an alternative treatment strategy to mitigate these concerns by using fully characterized recombinant proteins identified by the CM analysis to promote pro-regenerative healing. This study analyzed the secretome profile generated from human placental stem cell (hPSC) cultures and identified nine predominantly expressed proteins (ANG-1, FGF-7, Follistatin, HGF, IL-6, Insulin, TGFβ-1, uPAR, and VEGF) that are known to contribute to wound healing and angiogenesis. These proteins, referred to as s (CMFs), were used in combination to test the effects on human dermal fibroblasts (HDFs). Our results showed that CMF treatment increased the HDF growth and accelerated cell migration and wound closure, similar to stem cell and CM treatments. In addition, the CMF treatment promoted angiogenesis by enhancing new vessel formation. These findings suggest that the defined CMF identified by the CM proteomic analysis could be an effective therapeutic solution for wound healing applications. Our strategy eliminates the regulatory concerns present with stem cell-derived secretomes and could be developed as an off-the-shelf product for immediate wound care and accelerating healing.

EPDR1 is a noncanonical effector of insulin-mediated angiogenesis regulated by an endothelial-specific TGF-β receptor complex

Insulin signaling in blood vessels primarily functions to stimulate angiogenesis and maintain vascular homeostasis through the canonical PI3K and MAPK signaling pathways. However, angiogenesis is a complex process coordinated by multiple other signaling events. Here, we report a distinct crosstalk between the insulin receptor and endoglin/activin receptor-like kinase 1 (ALK1), an endothelial cell-specific TGF-β receptor complex essential for angiogenesis. While the endoglin-ALK1 complex normally binds to TGF-β or bone morphogenetic protein 9 (BMP9) to promote gene regulation via transcription factors Smad1/5, we show that insulin drives insulin receptor oligomerization with endoglin-ALK1 at the cell surface to trigger rapid Smad1/5 activation. Through quantitative proteomic analysis, we identify ependymin-related protein 1 (EPDR1) as a major Smad1/5 gene target induced by insulin but not by TGF-β or BMP9. We found endothelial EPDR1 expression is minimal at the basal state but is markedly enhanced upon prolonged insulin treatment to promote cell migration and formation of capillary tubules. Conversely, we demonstrate EPDR1 depletion strongly abrogates these angiogenic effects, indicating that EPDR1 is a crucial mediator of insulin-induced angiogenesis. Taken together, these results suggest important therapeutic implications for EPDR1 and the TGF-β pathways in pathologic angiogenesis during hyperinsulinemia and insulin resistance.

The effect of insulin on response to intravitreal anti-VEGF injection in diabetic macular edema in type 2 diabetes mellitus

Objectives

To assess whether insulin therapy impacts the effectiveness of anti-vascular endothelial growth factor (anti-VEGF) injection for the treatment of diabetic macular edema (DME) in type 2 diabetes mellitus.

Methods

This was a retrospective multi-center analysis. The best-corrected visual acuity (BCVA) at 12 months, BCVA change, central macular thickness (CMT), CMT change, and cumulative injection number were compared between the insulin and the oral hypoglycemic agent (OHA) groups.

Results

The mean final BCVA and CMT improved in both the insulin (N = 137; p < 0.001; p < 0.001, respectively) and the OHA group (N = 61; p = 0.199; p < 0.001, respectively). The two treatment groups were comparable for final BCVA (p = 0.263), BCVA change (p = 0.184), final CMT (p = 0.741), CMT change (p = 0.458), and the cumulative injections received (p = 0.594). The results were comparable between the two groups when stratified by baseline vision (p > 0.05) and baseline HbA1c (p > 0.05).

Conclusion

Insulin therapy does not alter treatment outcomes for anti-VEGF therapy in DME.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02325-x.

Mersal E, Razik H. Farrag A, M. Abdelmoneim A, M. Abdelmenem A, S. Salim M. Histomorphological Changes in a Rat Model of Polycystic Ovary Syndrome and the Contribution of Stevia Leaf Extract in Modulating the Ovarian Fibrosis, VEGF, and TGF-β Immunoexpressions: Comparison with Metformin

Polycystic ovary syndrome (PCOS) is a common endocrine disorder of fertile females. It has been reported that stevia leaf extract (SLE) has antidiabetic and antihyperlipidemic properties. Therefore, the current study hypothesized and investigated the role and mechanistic aspects of a natural sweetener; SLE in treating a rat model of letrozole-induced PCOS and to compare it with metformin. Thirty-five female Wistar albino rats were divided into 5 groups: control, PCOS-induced group (letrozole, 1 mg/kg/d, for 21 days), SLE, metformin, and combination-treated groups (300 mg/kg/d, for the next 28 days in SLE and metformin-treated groups). Vaginal smears were done. The levels of glucose, lipid, and hormonal profiles were measured in the serum meanwhile, malonyl dialdehyde (MDA), superoxide dismutase (SOD), and tumour necrosis factor (TNF-α) were measured in the ovary. Ovarian sections were subjected to hematoxylin and eosin, Masson, and immunohistochemical identification of VEGF and TGF-β followed by morphometric analysis. PCOS rats showed altered hormonal and lipid profiles, in addition to hyperglycemia. Also, the ovarian tissue levels of MDA and TNF-α were elevated, and SOD was decreased. Numerous cystic follicles, decrease/absence of corpora lutea, interstitial fibrosis with positive VEGF and TGF-β immunoreactivity were evident. SLE improved all altered parameters. SLE showed potential therapeutic merits in letrozole-induced PCOS via anti-inflammatory, antioxidant, anti-fibrotic, and angiogenesis regulating mechanisms. Its effects were almost comparable to metformin, and the combination of both has no further synergistic effect.

Dietary glycemic index, glycemic load and cancer risk: a meta-analysis of prospective cohort studies

PURPOSE

There is considerable inconsistency in results regarding the association of dietary glycemic index (GI) and glycemic load (GL) with cancer risk. We therefore conducted this systematic review and dose-response meta-analysis of prospective cohort studies to evaluate the relationship between dietary GI/GL and cancer risk.

METHODS

We searched PubMed and Web of Science for prospective cohort studies of dietary GI/GL in relation to risks of all types of cancer up to 31 March 2021. We used a random-effect model to calculate summary relative risks (RR) and 95% confidence intervals (CI). The certainty of evidence was assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. This study was registered at PROSPERO (CRD42020215338).

RESULTS

Overall, 55 cohorts were included in the meta-analysis. We assessed the relationship between dietary GI or GL and risks of 23 cancer types, including hormone-related cancers, cancers from digestive system, respiratory system, urinary system and other cancer sites. High GI diet increased overall risk of cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.04, 95% CI 1.01-1.07). For site-specific cancers, high GI diet increased risks of lung cancer (highest vs lowest categories, n = 5, RR 1.08, 95% CI 1.01-1.18) and breast cancer (highest vs lowest categories, n = 14, RR 1.05, 95% CI 1.01-1.09), especially for postmenopausal breast cancer (highest vs lowest categories, n = 10, RR 1.06, 95% CI 1.00-1.13), all with low certainty of evidence. Additionally, dietary GI was positively related to risk of bladder cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.23, 95% CI 1.09-1.40), as well as negatively related to ovarian cancer risk with very low certainty of evidence (highest vs lowest categories, n = 4, RR 0.83, 95% CI 0.69-1.00) and lymphoma risk with low certainty of evidence (highest vs lowest categories, n = 2, RR 0.84, 95% CI 0.72-0.98). Besides, we found an inverse association of dietary GL with lung cancer risk with low certainty of evidence (highest vs lowest categories, n = 5, RR 0.87, 95% CI 0.80-0.94).

CONCLUSION

High dietary GI increased overall cancer risk with low certainty of evidence. For site-specific cancers, high GI diet increased the risks of breast cancer with low certainty of evidence and lung cancer with low certainty of evidence. Dietary GL was inversely associated with lung cancer risk with low certainty of evidence.

A molecular link between diabetes and breast cancer: Therapeutic potential of repurposing incretin-based therapies for breast cancer

Female breast cancer recently surpassed lung cancer and became the most commonly diagnosed cancer worldwide. As per the recent data from WHO, breast cancer accounts for one out of every 8 cancer cases diagnosed among an estimated 2.3 million new cancer cases. Breast cancer is the most prevailing cancer type among women causing the highest number of cancer-related mortality. It has been estimated that in 2020, 68,5000 women died due to this disease. Breast cancers have varying degrees of molecular heterogeneity; therefore, they are divided into various molecular clinical sub types. Recent reports suggest that type 2 diabetes (one of the common chronic diseases worldwide) is linked to the higher incidence, accelerated progression, and aggressiveness of different cancers; especially breast cancer. Breast cancer is hormone-dependent in nature and has a cross-talk with metabolism. A number of antidiabetic therapies are known to exert beneficial effects on various types of cancers, including breast cancer. However, only a few reports are available on the role of incretin-based antidiabetic therapies in cancer as a whole and in breast cancer in particular. The present review sheds light on the potential of incretin based therapies on breast cancer and explores the plausible underlying mechanisms. Additionally, we have also discussed the sub types of breast cancer as well as the intricate relationship between diabetes and breast cancer.

A historical perspective on the interactions of insulin at the blood-brain barrier

Subsequent to the discovery of insulin in 1921, the role of insulin in the brain has been investigated throughly. The ability of insulin to act within the brain to regulate peripheral glucose levels helped evolve the research surrounding the ability of insulin to be transported into the brain. Investigations aiming to determine the transport of insulin into the brain from the circulation soon followed. Once it was established that insulin could enter the brain, the ability of insulin to bind brain microvessels and regulators of this process were determined. As technology advanced, quantitative measurements to specify the transport rate of insulin across the blood-brain barrier (BBB) and the impact of physiological conditions and diseases were the logical next steps. Lastly, with the advent of genetic mouse models and high-specificity antagonists, the specific role of the insulin receptor in mediating insulin transport could begin to be explored. In this review, we summarise the main findings throughout the decades regarding the interactions of insulin at the BBB.

Zinc chloride affects chondrogenesis via VEGF signaling

Insulin mimetics, including zinc containing compounds, have previously been shown to influence chondrogenesis as it relates to healing of fractures in various preclinical models. However, the mechanism by which these compounds drive chondrogenic differentiation is yet undefined. Here, via next-generation sequencing (NGS) and in vitro functional validation, we show that Zinc Chloride (ZnCl₂) induces expression of both chondrogenic genes (Sox9, Runx1, collagen) as well as genes associated with VEGF-mediated signal transduction, including VEGF receptors 1 and 2 and their ligands; VEGF-A and VEGF-B. Noticeably, although insulin was able to also induce expression of these pro-angiogenic and pro-chondrogenic genes, the impact of insulin on expression of VEGF receptor and ligand genes was marginal when compared to that of ZnCl_2. Furthermore, while the VEGFR antagonist, Axitinib, was able to attenuate the pro-chondrogenic effects of both insulin and ZnCl₂; a reduction in gene and protein expression was most profoundly observed when the antagonist was applied to cells treated with ZnCl_2. Taken together, these data suggest an important role for the VEGF-mediated signal transduction pathways in the positive effects observed when applying zinc-based compounds as adjuvants for chondrogenesis-mediated fracture healing. In this regard, further mechanistic evaluation of ZnCl₂ and other zinc-containing insulin mimetics may support rational design of therapies targeted for disease indications associated with impaired fracture healing.

Improvement of islet transplantation by the fusion of islet cells with functional blood vessels

Pancreatic islet transplantation still represents a promising therapeutic strategy for curative treatment of type 1 diabetes mellitus. However, a limited number of organ donors and insufficient vascularization with islet engraftment failure restrict the successful transfer of this approach into clinical practice. To overcome these problems, we herein introduce a novel strategy for the generation of prevascularized islet organoids by the fusion of pancreatic islet cells with functional native microvessels. These insulin-secreting organoids exhibit a significantly higher angiogenic activity compared to freshly isolated islets, cultured islets, and non-prevascularized islet organoids. This is caused by paracrine signaling between the β-cells and the microvessels, mediated by insulin binding to its corresponding receptor on endothelial cells. In vivo, the prevascularized islet organoids are rapidly blood-perfused after transplantation by the interconnection of their autochthonous microvasculature with surrounding blood vessels. As a consequence, a lower number of islet grafts are required to restore normoglycemia in diabetic mice. Thus, prevascularized islet organoids may be used to improve the success rates of clinical islet transplantation.

[Expression of tumor-associated vascular insulin receptor in colorectal cancer and its relationship with tumor pathological features]

OBJECTIVE

To study the expression of tumor associated vascular insulin receptor (TVIR) in colorectal cancer with or without metabolic syndrome (MS) and its relationship with the pathological features of colorectal cancer.

METHODS

The expression of TVIR in 220 colorectal cancer specimens was detected by tissue microarray and immunohistochemistry. The relationships between the expression of TVIR and the pathological features (pathological subtypes, histological grade, invasion depth, lymph node metastasis and TNM stage) of colorectal cancer with/without MS were analyzed.

RESULTS

The insulin receptor expression was observed in colorectal cancer tissue or border area between cancer and normal tissue, but not in normal intestinal tissue. The high-expression rates of TVIR in MS group was remarkably lower than that of non-MS group (21.6%vs. 41.0%, P< 0.05). TVIR high expression was significantly associated with tumor deep invasion, lymph node metastasis and high TNM stage (P<0.05 or P<0.01). Univariate logistic regression analysis showed high-expression of TVIR to be significantly associated with risk of deep invasion (OR=2.21, 95% CI: 1.10-4.44, P<0.05), lymph node metastasis (OR=2.21, 95% CI: 1.26-3.86, P<0.01) and high TNM stage (OR=2.08, 95% CI: 1.19-3.63, P<0.05). Such associations can be observed in patients without MS, but not in patients with MS.

CONCLUSIONS

s: High-expression of TVIR is associated with aggressive pathological features such as invasion, lymph node metastasis and high TNM stage of colorectal cancer, especially for those patients without MS. TVIR could be a useful biological marker for prognosis of colorectal cancer.

Identification of miRNAs as the Crosstalk in the Interaction between Neural Stem/Progenitor Cells and Endothelial Cells

AIM

This study is aimed at identifying genetic and epigenetic crosstalk molecules and their target drugs involved in the interaction between neural stem/progenitor cells (NSPCs) and endothelial cells (ECs).

MATERIALS AND METHODS

Datasets pertaining to reciprocal mRNA and noncoding RNA changes induced by the interaction between NSPCs and ECs were obtained from the GEO database. Differential expression analysis (DEA) was applied to identify NSPC-induced EC alterations by comparing the expression profiles between monoculture of ECs and ECs grown in EC/NSPC cocultures. DEA was also utilized to identify EC-induced NSPC alterations by comparing the expression profiles between monoculture of NSPCs and NSPCs grown in EC/NSPC cocultures. The DEGs and DEmiRNAs shared by NSPC-induced EC alterations and EC-induced NSPC alterations were then identified. Furthermore, miRNA crosstalk analysis and functional enrichment analysis were performed, and the relationship between DEmiRNAs and small molecular drug targets/environment chemical compounds was investigated.

RESULTS

One dataset (GSE29759) was included and analyzed in this study. Six genes (i.e., MMP14, TIMP3, LOXL1, CCK, SMAD6, and HSPA2), three miRNAs (i.e., miR-210, miR-230a, and miR-23b), and three pathways (i.e., Akt, ERK1/2, and BMPs) were identified as crosstalk molecules. Six small molecular drugs (i.e., deptropine, fluphenazine, lycorine, quinostatin, resveratrol, and thiamazole) and seven environmental chemical compounds (i.e., folic acid, dexamethasone, choline, doxorubicin, thalidomide, bisphenol A, and titanium dioxide) were identified to be potential target drugs of the identified DEmiRNAs.

CONCLUSION

To conclude, three miRNAs (i.e., miR-210, miR-230a, and miR-23b) were identified to be crosstalks linking the interaction between ECs and NSPCs by implicating in both angiogenesis and neurogenesis. These crosstalk molecules might provide a basis for devising novel strategies for fabricating neurovascular models in stem cell tissue engineering.

Regulation of Obesity by Antiangiogenic Herbal Medicines

Obesity is the result of an energy imbalance caused by an increased ratio of caloric intake to energy expenditure. In conjunction with obesity, related metabolic disorders, such as dyslipidemia, atherosclerosis, and type 2 diabetes, have become global health problems. Obesity progression is thought to be associated with angiogenesis and extracellular matrix (ECM) remodeling. Angiogenesis occurs in growing adult adipose tissues, which are similar to neoplastic tissues. Adipose tissue is highly vascularized, and each adipocyte is nourished by an extensive capillary network. Adipocytes produce proangiogenic factors, such as vascular endothelial growth factor A and fibroblast growth factor 2, which promote neovascularization within the adipose tissue. Furthermore, matrix metalloproteinases (MMPs), including MMP-2 and MMP-9, play important roles in adipose tissue development and microvessel maturation by modifying the ECM. Thus, modulation of angiogenesis and MMP activity provides a promising therapeutic approach for controlling human obesity and its related disorders. Over the past decade, there has been a great increase in the use of alternative treatments, such as herbal remedies, for these diseases. This review will focus on the role of angiogenesis in adipose tissue growth and the regulation of obesity by antiangiogenic herbal medicines.

Systems Biology Will Direct Vascular-Targeted Therapy for Obesity

Healthy adipose tissue expansion and metabolism during weight gain require coordinated angiogenesis and lymphangiogenesis. These vascular growth processes rely on the vascular endothelial growth factor (VEGF) family of ligands and receptors (VEGFRs). Several studies have shown that controlling vascular growth by regulating VEGF:VEGFR signaling can be beneficial for treating obesity; however, dysregulated angiogenesis and lymphangiogenesis are associated with several chronic tissue inflammation symptoms, including hypoxia, immune cell accumulation, and fibrosis, leading to obesity-related metabolic disorders. An ideal obesity treatment should minimize adipose tissue expansion and the advent of adverse metabolic consequences, which could be achieved by normalizing VEGF:VEGFR signaling. Toward this goal, a systematic investigation of the interdependency of vascular and metabolic systems in obesity and tools to predict personalized treatment ranges are necessary to improve patient outcomes through vascular-targeted therapies. Systems biology can identify the critical VEGF:VEGFR signaling mechanisms that can be targeted to regress adipose tissue expansion and can predict the metabolic consequences of different vascular-targeted approaches. Establishing a predictive, biologically faithful platform requires appropriate computational models and quantitative tissue-specific data. Here, we discuss the involvement of VEGF:VEGFR signaling in angiogenesis, lymphangiogenesis, adipogenesis, and macrophage specification – key mechanisms that regulate adipose tissue expansion and metabolism. We then provide useful computational approaches for simulating these mechanisms, and detail quantitative techniques for acquiring tissue-specific parameters. Systems biology, through computational models and quantitative data, will enable an accurate representation of obese adipose tissue that can be used to direct the development of vascular-targeted therapies for obesity and associated metabolic disorders.

Serum insulin levels are associated with vulnerable plaque components in the carotid artery: the Rotterdam Study

BACKGROUND

To investigate the association between fasting serum insulin and glucose levels with atherosclerotic plaque composition in the carotid artery. Impaired insulin and glucose levels are implicated in the etiology of cardiovascular disease; however, their influence on the formation and composition of atherosclerotic plaque remains unclear.

METHODS

In 1740 participants (mean age 72.9 years, 46% women, 14.4% diabetes mellitus) from the population-based Rotterdam Study, we performed carotid MRI to evaluate the presence of calcification, lipid core, and intraplaque hemorrhage in carotid atherosclerosis. All participants also underwent blood sampling to obtain information on serum insulin and glucose levels. Using logistic regression models, we assessed the association of serum insulin and glucose levels (per s.d. and in tertiles) with the different plaque components, while adjusting for sex, age, intima-media thickness, and cardiovascular risk factors.

RESULTS

Serum insulin levels were associated with the presence of intraplaque hemorrhage (adjusted odds ratio (OR): 1.42 (95% CI: 1.12-1.7)) We found no association with the presence of calcification or lipid core. Sensitivity analyses restricted to individuals without diabetes mellitus yielded similar results. No associations were found between serum glucose levels and any of the plaque components.

CONCLUSIONS

Serum insulin levels are associated with the presence of vulnerable components of carotid plaque, specifically with intraplaque hemorrhage. These findings suggest a complex role for serum insulin in the pathophysiology of carotid atherosclerosis and in plaque vulnerability.

Multiple Cell Signalling Pathways of Human Proinsulin C-Peptide in Vasculopathy Protection

A major hallmark of diabetes is a constant high blood glucose level (hyperglycaemia), resulting in endothelial dysfunction. Transient or prolonged hyperglycemia can cause diabetic vasculopathy, a secondary systemic damage. C-Peptide is a product of cleavage of proinsulin by a serine protease that occurs within the pancreatic β-cells, being secreted in similar amounts as insulin. The biological activity of human C-peptide is instrumental in the prevention of diabetic neuropathy, nephropathy and other vascular complications. The main feature of type 1 diabetes mellitus is the lack of insulin and of C-peptide, but the progressive β-cell loss is also observed in later stage of type 2 diabetes mellitus. C-peptide has multifaceted effects in animals and diabetic patients due to the activation of multiple cell signalling pathways, highlighting p38 mitogen-activated protein kinase and extracellular signal-regulated kinase ½, Akt, as well as endothelial nitric oxide production. Recent works highlight the role of C-peptide in the prevention and amelioration of diabetes and also in organ-specific complications. Benefits of C-peptide in microangiopathy and vasculopathy have been shown through conservation of vascular function, and also in the prevention of endothelial cell death, microvascular permeability, neointima formation, and in vascular inflammation. Improvement of microvascular blood flow by replacing a physiological amount of C-peptide, in several tissues of diabetic animals and humans, mainly in nerve tissue, myocardium, skeletal muscle, and kidney has been described. A review of the multiple cell signalling pathways of human proinsulin C-peptide in vasculopathy protection is proposed, where the approaches to move beyond the state of the art in the development of innovative and effective therapeutic options of diabetic neuropathy and nephropathy are discussed.

Metabolic Health, Insulin, and Breast Cancer: Why Oncologists Should Care About Insulin

Studies investigating the potential link between adult pre-menopausal obesity [as measured by body mass index (BMI)] and triple-negative breast cancer have been inconsistent. Recent studies show that BMI is not an exact measure of metabolic health; individuals can be obese (BMI > 30 kg/m²) and metabolically healthy or lean (BMI < 25 kg/m²) and metabolically unhealthy. Consequently, there is a need to better understand the molecular signaling pathways that might be activated in individuals that are metabolically unhealthy and how these signaling pathways may drive biologically aggressive breast cancer. One key driver of both type-2 diabetes and cancer is insulin. Insulin is a potent hormone that activates many pathways that drive aggressive breast cancer biology. Here, we review (1) the controversial relationship between obesity and breast cancer, (2) the impact of insulin on organs, subcellular components, and cancer processes, (3) the potential link between insulin-signaling and cancer, and (4) consider time points during breast cancer prevention and treatment where insulin-signaling could be better controlled, with the ultimate goal of improving overall health, optimizing breast cancer prevention, and improving breast cancer survival.

Endothelial cell CD36 deficiency prevents normal angiogenesis and vascular repair

Endothelial cells (ECs) maintain vascular integrity and mediate vascular repair and angiogenesis, by which new blood vessels are formed from pre-existing blood vessels. Hyperglycemia has been shown to increase EC angiogenic potential. However, few studies have investigated effects of fatty acids (FAs) on EC angiogenesis. Cluster of differentiation 36 (CD36) is a FA transporter expressed by ECs, but its role in EC proliferation, migration, and angiogenesis is unknown. We sought to determine if circulating FAs regulate angiogenic function in a CD36-dependent manner. CD36-dependent effects of FAs on EC proliferation and migration of mouse heart ECs (MHECs) and lung ECs (MLECs) were studied. We used both silencing RNA and antisense oligonucleotides to reduce CD36 expression. Oleic acid (OA) did not affect EC proliferation, but significantly increased migration of ECs in wound healing experiments. CD36 knockdown prevented OA-induced increases in wound healing potential. In EC transwell migration experiments, OA increased recruitment and migration of ECs, an effect abolished by CD36 knockdown. Phospho-AMP-activated protein kinase (AMPK) increased in MHECs exposed to OA in a CD36-dependent manner. To test whether in vivo CD36 affects angiogenesis, we studied 21-day recovery in post-hindlimb ischemia. EC-specific CD36 knockout mice had reduced blood flow recovery as assessed by laser Doppler imaging. EC content in post-ischemic muscle, assessed from CD31 expression, increased in ischemic muscle of control mice. However, mice with EC-specific CD36 deletion lacked the increase in CD31 and matrix metalloprotease 9 expression observed in controls. EC expression of CD36 and its function in FA uptake modulate angiogenic function and response to ischemia, likely due to reduced activation of the AMPK pathway.

Integration of TGF-β-induced Smad signaling in the insulin-induced transcriptional response in endothelial cells

Insulin signaling governs many processes including glucose homeostasis and metabolism, and is therapeutically used to treat hyperglycemia in diabetes. We demonstrated that insulin-induced Akt activation enhances the sensitivity to TGF-β by directing an increase in cell surface TGF-β receptors from a pool of intracellular TGF-β receptors. Consequently, increased autocrine TGF-β signaling in response to insulin participates in insulin-induced angiogenic responses of endothelial cells. With TGF-β signaling controlling many cell responses, including differentiation and extracellular matrix deposition, and pathologically promoting fibrosis and cancer cell dissemination, we addressed to which extent autocrine TGF-β signaling participates in insulin-induced gene responses of human endothelial cells. Transcriptome analyses of the insulin response, in the absence or presence of a TGF-β receptor kinase inhibitor, revealed substantial positive and negative contributions of autocrine TGF-β signaling in insulin-responsive gene responses. Furthermore, insulin-induced responses of many genes depended on or resulted from autocrine TGF-β signaling. Our analyses also highlight extensive contributions of autocrine TGF-β signaling to basal gene expression in the absence of insulin, and identified many novel TGF-β-responsive genes. This data resource may aid in the appreciation of the roles of autocrine TGF-β signaling in normal physiological responses to insulin, and implications of therapeutic insulin usage.

Mechanistic Links Between Obesity, Diabetes, and Blood Pressure: Role of Perivascular Adipose Tissue

Obesity is increasingly prevalent and is associated with substantial cardiovascular risk. Adipose tissue distribution and morphology play a key role in determining the degree of adverse effects, and a key factor in the disease process appears to be the inflammatory cell population in adipose tissue. Healthy adipose tissue secretes a number of vasoactive adipokines and anti-inflammatory cytokines, and changes to this secretory profile will contribute to pathogenesis in obesity. In this review, we discuss the links between adipokine dysregulation and the development of hypertension and diabetes and explore the potential for manipulating adipose tissue morphology and its immune cell population to improve cardiovascular health in obesity.

Role of the Blood-Brain Barrier in Central Nervous System Insulin Resistance

The blood-brain barrier (BBB) mediates the communication between the periphery and the central nervous system (CNS). Recently, CNS insulin resistance has been elucidated to play a role in neurodegenerative disease. This has stimulated a wealth of information on the molecular impact of insulin in the brain, particularly in the improvement of cognition. Since the BBB regulates the transport of insulin into the brain and thus, helps to regulate CNS levels, alterations in the BBB response to insulin could impact CNS insulin resistance. In this review, we summarize the effect of insulin on some of the cell types that make up the BBB, including endothelial cells, neurons, astrocytes, and pericytes. We broadly discuss how these changes in specific cell types could ultimately impact the BBB. We also summarize how insulin can regulate levels of the pathological hallmarks of Alzheimer's disease, including amyloid beta (Aβ) and tau within each cell type. Finally, we suggest interventional approaches to overcome detrimental effects on the BBB in regards to changes in insulin transport.

Insulin and Insulin Receptors in Adipose Tissue Development

Insulin is a major endocrine hormone also involved in the regulation of energy and lipid metabolism via the activation of an intracellular signaling cascade involving the insulin receptor (INSR), insulin receptor substrate (IRS) proteins, phosphoinositol 3-kinase (PI3K) and protein kinase B (AKT). Specifically, insulin regulates several aspects of the development and function of adipose tissue and stimulates the differentiation program of adipose cells. Insulin can activate its responses in adipose tissue through two INSR splicing variants: INSR-A, which is predominantly expressed in mesenchymal and less-differentiated cells and mainly linked to cell proliferation, and INSR-B, which is more expressed in terminally differentiated cells and coupled to metabolic effects. Recent findings have revealed that different distributions of INSR and an altered INSR-A:INSR-B ratio may contribute to metabolic abnormalities during the onset of insulin resistance and the progression to type 2 diabetes. In this review, we discuss the role of insulin and the INSR in the development and endocrine activity of adipose tissue and the pharmacological implications for the management of obesity and type 2 diabetes.

Enhanced TGF-β Signaling Contributes to the Insulin-Induced Angiogenic Responses of Endothelial Cells

Angiogenesis, the development of new blood vessels, is a key process in disease. We reported that insulin promotes translocation of transforming growth factor β (TGF-β) receptors to the plasma membrane of epithelial and fibroblast cells, thus enhancing TGF-β responsiveness. Since insulin promotes angiogenesis, we addressed whether increased autocrine TGF-β signaling participates in endothelial cell responses to insulin. We show that insulin enhances TGF-β responsiveness and autocrine TGF-β signaling in primary human endothelial cells, by inducing a rapid increase in cell surface TGF-β receptor levels. Autocrine TGF-β/Smad signaling contributed substantially to insulin-induced gene expression associated with angiogenesis, including TGF-β target genes encoding angiogenic mediators; was essential for endothelial cell migration; and participated in endothelial cell invasion and network formation. Blocking TGF-β signaling impaired insulin-induced microvessel outgrowth from neonatal aortic rings and modified insulin-stimulated blood vessel formation in zebrafish. We conclude that enhanced autocrine TGF-β signaling is integral to endothelial cell and angiogenic responses to insulin.

Pericytes in Alzheimer's Disease: Novel Clues to Cerebral Amyloid Angiopathy Pathogenesis

Pericytes in the central nervous system attract growing attention of neurobiologists because of obvious opportunities to use them as target cells in numerous brain diseases. Functional activity of pericytes includes control of integrity of the endothelial cell layer, regeneration of vascular cells, and regulation of microcirculation. Pericytes are well integrated in the so-called neurovascular unit (NVU) serving as a platform for effective communications of neurons, astrocytes, endothelial cells, and pericytes. Contribution of pericytes to the establishment and maintaining the structural and functional integrity of blood-brain barrier is confirmed in numerous experimental and clinical studies. The review covers current understandings on the role of pericytes in molecular pathogenesis of NVU/BBB dysfunction in Alzheimer's disease with the special focus on the development of cerebral amyloid angiopathy, deregulation of cerebral angiogenesis, and progression of BBB breakdown seen in Alzheimer's type neurodegeneration.

Sialic acid as a target for the development of novel antiangiogenic strategies

Sialic acid is associated with glycoproteins and gangliosides of eukaryotic cells. It regulates various molecular interactions, being implicated in inflammation and cancer, where its expression is regulated by sialyltransferases and sialidases. Angiogenesis, the formation of new capillaries, takes place during inflammation and cancer, and represents the outcome of several interactions occurring at the endothelial surface among angiogenic growth factors, inhibitors, receptors, gangliosides and cell-adhesion molecules. Here, we elaborate on the evidences that many structures involved in angiogenesis are sialylated and that their interactions depend on sialic acid with implications in angiogenesis itself, inflammation and cancer. We also discuss the possibility to exploit sialic acid as a target for the development of novel antiangiogenic drugs.

Acyclic retinoid and angiotensin-II receptor blocker exert a combined protective effect against diethylnitrosamine-induced hepatocarcinogenesis in diabetic OLETF rats

Background

Insulin resistance (IR) is closely associated with the progression of hepatocellular carcinoma (HCC). Acyclic retinoid (ACR) targets retinoid X receptor α and reportedly prevents HCC recurrence in clinical practice. Angiotensin-II receptor blocker (ARB) can also inhibit experimental hepatocarcinogenesis and HCC development. These are reported to suppress IR-based hepatocarcinogenesis; however, limited data are available regarding the combined effects of both these agents. This study aimed to investigate the combined chemopreventive effect of ACR and ARB on liver tumorigenesis on rats with congenital diabetes.

Methods

Male diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats underwent 70% partial hepatectomy following a single intraperitoneal injection of diethylnitrosamine to induce hepatocarcinogenesis and the administration of ACR (peretinoin, 40 mg/kg/day), ARB (losartan, 30 mg/kg/day), and a combination of ACR and ARB. Six weeks thereafter, we assessed the size and number of the pre-neoplastic lesions (PNL) as well as the altered angiogenesis, oxidative stress, and chronic inflammation in the liver. Moreover, we assessed the effects exerted by ACR and ARB on in vitro cell growth in human HCC cell lines and human umbilical vascular endothelial cells (HUVECs).

Results

OLETF rats showed increase in the size and number of PNLs compared to LETO rats. ACR suppressed the augmentation in size and number of PNLs in the OLETF rats with suppression of cell growth, intrahepatic angiogenesis, lipid peroxidation, oxidative DNA damage, and proinflammatory cytokine production. Combining ACR with ARB enhanced the tumor-suppressive effect and ameliorated intrahepatic angiogenesis, lipid peroxidation, and proinflammatory status; however, cell growth and oxidative DNA damage remained unchanged. IR-mimetic condition accelerated in vitro proliferative activity in human HCC cells, while ACR inhibited this proliferation with G0/G1 arrest and apoptosis. Furthermore, ACR and ARB significantly attenuated the HUVECs proliferation and tubular formation under the IR-mimetic condition, and a combination of both agents demonstrated greater inhibitory effects on HUVEC growth than each single treatment.

Conclusions

ACR and ARB exert a combined inhibitory effect against IR-based hepatocarcinogenesis by the inhibition of cell growth, intrahepatic angiogenesis, and oxidative stress. Thus, this combination therapy appears to hold potential as a chemopreventive treatment therapy against HCC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5099-6) contains supplementary material, which is available to authorized users.

The Effects of Metformin and Weight Loss on Biomarkers Associated With Breast Cancer Outcomes

Background

This study investigated the effects of metformin and weight loss on biomarkers associated with breast cancer prognosis.

Methods

Overweight/obese postmenopausal breast cancer survivors (n = 333) were randomly assigned to metformin vs placebo and to a weight loss intervention vs control (ie, usual care). The 2 × 2 factorial design allows a single randomized trial to investigate the effect of two factors and interactions between them. Outcomes were changes in fasting insulin, glucose, C-reactive protein (CRP), estradiol, testosterone, and sex-hormone binding globulin (SHBG). The trial was powered for a main effects analysis of metformin vs placebo and weight loss vs control. All tests of statistical significance were two-sided.

Results

A total of 313 women (94.0%) completed the six-month trial. High prescription adherence (ie, ≥80% of pills taken) ranged from 65.9% of participants in the metformin group to 81.3% of those in the placebo group (P < .002). Mean percent weight loss was statistically significantly higher in the weight loss group (-5.5%, 95% confidence interval [CI] = -6.3% to -4.8%) compared with the control group (-2.7%, 95% CI = -3.5% to -1.9%). Statistically significant group differences (ie, percent change in metformin group minus placebo group) were -7.9% (95% CI = -15.0% to -0.8%) for insulin, -10.0% (95% CI = -18.5% to -1.5%) for estradiol, -9.5% (95% CI = -15.2% to -3.8%) for testosterone, and 7.5% (95% CI = 2.4% to 12.6%) for SHBG. Statistically significant group differences (ie, percent change in weight loss group minus placebo group) were -12.5% (95% CI = -19.6% to -5.3%) for insulin and 5.3% (95% CI = 0.2% to 10.4%) for SHBG.

Conclusions

As adjuvant therapy, weight loss and metformin were found to be a safe combination strategy that modestly lowered estrogen levels and advantageously affected other biomarkers thought to be on the pathway for reducing breast cancer recurrence and mortality.

Angiogenic Dysregulation in Pregnancy-Related Hypertension-A Role for Metformin

In the face of escalating maternal and fetal health threats, hypertensive pregnancy disorders (HPDs) is one of the leading cause of maternal and fetal morbidity and mortality. The range of HPDs include white-coat hypertension, chronic hypertension, gestational hypertension, mild-to-moderate and severe preeclampsia and eclampsia. Current evidence implicates an imbalance of circulating anti- and angiogenic factors in HPDs emanating from the placental vasculature, impacting on angiogenesis. Delivery of the fetus is thus far the only curative measure, albeit with increased risk. Resultant endothelial dysfunction caused by the excessive production of placental soluble fms-like tyrosine kinase-1 has been the basis of many studies to find a safer treatment strategy. Metformin, used historically in the treatment of diabetes mellitus has also found its therapeutic reach in many other disease states. These include, but are not limited to, improving blood flow in certain cancer types, treatment of polycystic ovarian disease, improving vasodilation, and reducing inflammation. Metformin is used to treat hyperglycemic endothelial dysfunction through the enhancement of the nitric oxide system, endothelin-derived hyperpolarizing factor and sirtuin 1. Similarly, endothelial dysfunction in preeclampsia and other HPDs leads to a hypoxic state and elevated blood pressures. Dubbed as the new "aspirin" of current times, the retardation of the antiangiogenic status by metformin provides an exciting and promising alternate strategy in treating these pregnancy disorders.

Treatment with a New Peroxisome Proliferator-Activated Receptor Gamma Agonist, Pyridinecarboxylic Acid Derivative, Increases Angiogenesis and Reduces Inflammatory Mediators in the Heart of Trypanosoma cruzi-Infected Mice

Trypanosoma cruzi infection induces an intense inflammatory response in diverse host tissues. The immune response and the microvascular abnormalities associated with infection are crucial aspects in the generation of heart damage in Chagas disease. Upon parasite uptake, macrophages, which are involved in the clearance of infection, increase inflammatory mediators, leading to parasite killing. The exacerbation of the inflammatory response may lead to tissue damage. Peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-dependent nuclear transcription factor that exerts important anti-inflammatory effects and is involved in improving endothelial functions and proangiogenic capacities. In this study, we evaluated the intermolecular interaction between PPARγ and a new synthetic PPARγ ligand, HP₂₄, using virtual docking. Also, we showed that early treatment with HP₂₄, decreases the expression of NOS2, a pro-inflammatory mediator, and stimulates proangiogenic mediators (vascular endothelial growth factor A, CD31, and Arginase I) both in macrophages and in the heart of T. cruzi-infected mice. Moreover, HP₂₄ reduces the inflammatory response, cardiac fibrosis and the levels of inflammatory cytokines (TNF-α, interleukin 6) released by macrophages of T. cruzi-infected mice. We consider that PPARγ agonists might be useful as coadjuvants of the antiparasitic treatment of Chagas disease, to delay, reverse, or preclude the onset of heart damage.

Surface marker profiling of SH-SY5Y cells enables small molecule screens identifying BMP4 as a modulator of neuroblastoma differentiation

Neuroblastoma is the most common extra-cranial solid tumor in children. Its broad spectrum of clinical outcomes reflects the underlying inherent cellular heterogeneity. As current treatments often do not lead to tumor eradication, there is a need to better define therapy-resistant neuroblastoma and to identify new modulatory molecules. To this end, we performed the first comprehensive flow cytometric characterization of surface molecule expression in neuroblastoma cell lines. Exploiting an established clustering algorithm (SPADE) for unbiased visualization of cellular subsets, we conducted a multiwell screen for small molecule modulators of neuroblastoma phenotype. In addition to SH-SY5Y cells, the SH-EP, BE(2)-M17 and Kelly lines were included in follow-up analysis as in vitro models of neuroblastoma. A combinatorial detection of glycoprotein epitopes (CD15, CD24, CD44, CD57, TrkA) and the chemokine receptor CXCR4 (CD184) enabled the quantitative identification of SPADE-defined clusters differentially responding to small molecules. Exposure to bone morphogenetic protein (BMP)-4 was found to enhance a TrkA^high/CD15⁻/CD184⁻ neuroblastoma cellular subset, accompanied by a reduction in doublecortin-positive neuroblasts and of NMYC protein expression in SH-SY5Y cells. Beyond yielding novel marker candidates for studying neuroblastoma pathology, our approach may provide tools for improved pharmacological screens towards developing novel avenues of neuroblastoma diagnosis and treatment.

Energy imbalance and cancer: Cause or consequence?

Obesity has been an epidemic worldwide over the past decades and significantly increases the risk of developing a variety of deadly diseases including type 2 diabetes, cardiovascular diseases and many cancers. The relationship between obesity and type 2 diabetes and cardiovascular disease has been well documented. The drastically increased frequency of a number of cancers in obesity has attracted growing interest. On one hand, how increased adiposity promotes cancer development remains poorly understood, despite the fact that considerable epidemiological evidence has suggested links between them. On the other hand, however, numerous studies have shown that tumorigenesis leads to substantial weight loss in a large portion of cancer patients. Here, we summarize the recent advances on our understanding of the link between obesity and cancer development with a focus on the molecular mechanisms accounting for the rising cancer incidence in the context of obesity. In addition, we also discuss how cancer-associated anorexia and cachexia causes weight loss. © 2017 IUBMB Life, 69(10):776-784, 2017.

A Novel Heterogalactan from Antrodia camphorata and Anti-Angiogenic Activity of Its Sulfated Derivative

A heterogalactan, named ACW0, was extracted from Antrodia camphorata and purified by anion exchange and gel permeation chromatography. It was composed of galactose (94.98%), traces of mannose (2.41%), and fucose (2.61%), with its molecular weight estimated to be 13.5 k Da. The polysaccharide ACW0 was shown to be a mannofucogalactan with a backbone chain of α-d-1,6-linked Gal, attached by a non-reducing terminal α-d-Man and α-l-Fuc on C-2 of nearly every six α-d-1,6-linked Gal residues. A sulfated polysaccharide, ACW0-Sul was achieved by the chlorosulfonic acid-pyridine method. Compared with the native polysaccharide, ACW0-Sul could disrupt tube formation and migration as well as cell growth of human microvascular endothelial cells (HMEC-1) dose-dependently. Further studies revealed that phosphorylation of Extracellular Regulated Protein Kinases (Erk) and Focal Adhesion Kinase (FAK) were significantly inhibited by ACW0-Sul. These results suggested that ACW0-Sul could be a potent candidate for anti-angiogenic agent development.

Angiogenesis in metabolic-vascular disease

Angiogenesis, literally formation of new blood vessels, is the main process through which the vascular system expands during embryonic and postnatal development. Endothelial cells, which constitute the inner lining of all blood vessels, are typically in a quiescent state in the healthy adult organism. However, in vascular and metabolic diseases, the endothelium becomes unstable and dysfunctional. The resulting tissue hypoxia may thereby induce pathological angiogenesis, which is a hallmark of disease conditions like cancer or diabetic retinopathy. However, recent evidence suggests that angiogenesis is also a major player in the context of further metabolic diseases, especially in obesity. In particular, deregulated angiogenesis is linked with adipose tissue dysfunction and insulin resistance. On the other hand, signalling pathways, such as the PI3K pathway, may regulate metabolic activities in the endothelium. Endothelial cell metabolism emerges as an important regulator of angiogenesis. This review summarises the role of angiogenesis in metabolic-vascular disease, with specific focus on the role of angiogenesis in obesity-related metabolic dysfunction and on signaling pathways, especially PI3K, linking cell metabolism to endothelial function.