Detection of cell-free histones in the cerebrospinal fluid of pediatric central nervous system malignancies by imaging flow cytometry.

Introduction: Pediatric brain tumours (PBT) are one of the most common malignancies during childhood, with variable severity according to the location and histological type. Certain types of gliomas, such a glioblastoma and diffuse intrinsic pontine glioma (DIPG), have a much higher mortality than ependymoma and medulloblastoma. Early detection of PBT is essential for diagnosis and therapeutic interventions. Liquid biopsies have been demonstrated using cerebrospinal fluid (CSF), mostly restricted to cell free DNA, which display limitations of quantity and integrity. In this pilot study, we sought to demonstrate the detectability and robustness of cell free histones in the CSF. Methods: We collected CSF samples from a pilot cohort of 8 children with brain tumours including DIPG, medulloblastoma, glioblastoma, ependymoma and others. As controls, we collected CSF samples from nine children with unrelated blood malignancies and without brain tumours. We applied a multichannel flow imaging approach on ImageStream(X) to image indiviual histone or histone complexes on different channels. Results: Single histones (H2A, macroH2A1.1, macroH2A1.2 H2B, H3, H4 and histone H3 bearing the H3K27M mutation), and histone complexes are specifically detectable in the CSF of PBT patients. H2A and its variants macroH2A1.1/macroH2A1/2 displayed the strongest signal and abundance, together with disease associated H3K27M. In contrast, mostly H4 is detectable in the CSF of pediatric patients with blood malignancies. Discussion: In conclusion, free histones and histone complexes are detectable with a strong signal in the CSF of children affected by brain tumours, using ImageStream(X) technology and may provide additive diagnostic and predictive information.

Human centenarian-associated SIRT6 mutants modulate hepatocyte metabolism and collagen deposition in multilineage hepatic 3D spheroids.

Non-alcoholic fatty liver disease (NAFLD), encompassing fatty liver and its progression into nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC), is one of the rapidly rising health concerns worldwide. SIRT6 is an essential nuclear sirtuin that regulates numerous pathological processes including insulin resistance and inflammation, and recently it has been implicated in the amelioration of NAFLD progression. SIRT6 overexpression protects from formation of fibrotic lesions. However, the underlying molecular mechanisms are not fully delineated. Moreover, new allelic variants of SIRT6 (N308K/A313S) were recently associated with the longevity in Ashkenazi Jews by improving genome maintenance and DNA repair, suppressing transposons and killing cancer cells. Whether these new SIRT6 variants play different or enhanced roles in liver diseases is currently unknown. In this study, we aimed to clarify how these new centenarian-associated SIRT6 genetic variants affect liver metabolism and associated diseases. We present evidence that overexpression of centenarian-associated SIRT6 variants dramatically altered the metabolomic and secretomic profiles of unchallenged immortalized human hepatocytes (IHH). Most amino acids were increased in the SIRT6 N308K/A313S overexpressing IHH when compared to IHH transfected with the SIRT6 wild-type sequence. Several unsaturated fatty acids and glycerophospholipids were increased, and ceramide tended to be decreased upon SIRT6 N308K/A313S overexpression. Furthermore, we found that overexpression of SIRT6 N308K/A313S in a 3D hepatic spheroid model formed by the co-culture of human immortalized hepatocytes (IHH) and hepatic stellate cells (LX2) inhibited collagen deposition and fibrotic gene expression in absence of metabolic or dietary challenges. Hence, our findings suggest that novel longevity associated SIRT6 N308K/A313S variants could favor the prevention of NASH by altering hepatocyte proteome and lipidome.

Profiling of cell-free DNA methylation and histone signatures in pediatric NAFLD: A pilot study.

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in children and adolescents, increasing the risk of its progression toward nonalcoholic steatohepatitis (NASH), cirrhosis, and cancer. There is an urgent need for noninvasive early diagnostic and prognostic tools such as epigenetic marks (epimarks), which would replace liver biopsy in the future. We used plasma samples from 67 children with biopsy-proven NAFLD, and as controls we used samples from 20 children negative for steatosis by ultrasound. All patients were genotyped for patatin-like phospholipase domain containing 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2), membrane bound O-acyltransferase domain containing 7 (MBOAT7), and klotho-ß (KLB) gene variants, and data on anthropometric and biochemical parameters were collected. Furthermore, plasma cell-free DNA (cfDNA) methylation was quantified using a commercially available kit, and ImageStream(X) was used for the detection of free circulating histone complexes and variants. We found a significant enrichment of the levels of histone macroH2A1.2 in the plasma of children with NAFLD compared to controls, and a strong correlation between cfDNA methylation levels and NASH. Receiver operating characteristic curve analysis demonstrated that combination of cfDNA methylation, PNPLA3 rs738409 variant, coupled with either high-density lipoprotein cholesterol or alanine aminotransferase levels can strongly predict the progression of pediatric NAFLD to NASH with area under the curve >0.87. Conclusion: Our pilot study combined epimarks and genetic and metabolic markers for a robust risk assessment of NAFLD development and progression in children, offering a promising noninvasive tool for the consistent diagnosis and prognosis of pediatric NAFLD. Further studies are necessary to identify their pathogenic origin and function.

The costs and benefits of senotherapeutics for human health.

Cellular senescence is a major contributor to age-related diseases in humans; however, it also has a beneficial role in physiological and pathological processes, including wound healing, host immunity, and tumour suppression. Reducing the burden of cell senescence in animal models of cardiometabolic disorders, inflammatory conditions, neurodegenerative diseases, and cancer using pharmaceutical approaches that selectively target senescent cells (ie, senolytics) or that suppress senescence-associated secretory phenotype (ie, senomorphics) holds great promise for the management of chronic age-associated conditions. Although studies have provided evidence that senolytics or senomorphics are effective at decreasing the number of senescent cells in humans, the short-term and long-term side-effects of these therapies are largely unknown. In this Review, we systematically discuss the senolytics and senomorphics that have been investigated in clinical trials or have been used off-label, presenting their various adverse effects. Despite the potential of senotherapeutics to transform anti-ageing medicine, a cautionary approach regarding unwanted dose-dependent side-effects should be adopted.

Bioactive Compounds from Lemon (Citrus limon) Extract Overcome TNF-α-Induced Insulin Resistance in Cultured Adipocytes.

The consumption of plant-based food is important for health promotion, especially regarding the prevention and management of chronic diseases such as diabetes. We investigated the effects of a lemon extract (LE), containing ≥20.0% total flavanones and ≥1.0% total hydroxycinnamic acids, on insulin signaling in murine 3T3-L1 adipocytes treated with TNF-α, which was used to mimic in vitro the insulin resistance condition that characterizes diabetes mellitus. Our results showed LE increased PPARγ, GLUT4 and DGAT-1 levels, demonstrating the potential of this lemon extract in the management of insulin resistance conditions associated with TNF-α pathway activation. LE treatment further decreased the release of interleukin 6 (IL-6) and restored triglyceride synthesis, which is the main feature of a healthy adipocyte.

Mild exacerbation of obesity- and age-dependent liver disease progression by senolytic cocktail dasatinib + quercetin.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. A minority of affected patients develops inflammation, subsequently fibrosis, cirrhosis and hepatocellular carcinoma (HCC). HCC is a leading cause of cancer-related death. An increased number of senescent cells correlate with age-related tissue degeneration during NAFLD-induced HCC. Senolytics are promising agents that target selectively senescent cells. Previous studies showed that whereas a combination of the senolytic drugs dasatinib and quercetin (D + Q) reduced NAFLD in mice, D + Q lacked efficacy in removing doxorubicin-induced ß-gal-positive senescent cells in human HCC xenografted mice. Whether D + Q has an effect on the age-associated spectrum of NAFLD-inflammation-HCC remains unknown. METHODS: Here, we utilized an established model of age- and obesity-associated HCC, the low dose diethylnitrosamine (DEN)/high fat diet (HFD), a regimen promoting liver inflammation and tumorigenesis over a long period of 9 months. Four groups of mice each were created: group 1 included control untreated mice; group 2 included mice treated with D + Q; group 3 included mice undergoing the DEN/HFD protocol; group 4 included mice undergoing the DEN/HFD protocol with the administration of D + Q. At the end of the chemical/dietary regimen, we analyzed liver damage and cell senescence by histopathology, qPCR and immunoblotting approaches. RESULTS: Unexpectedly, D + Q worsened liver disease progression in the DEN/HFD mouse model, slightly increasing histological damage and tumorigenesis, while having no effect on senescent cells removal. CONCLUSIONS: In summary, using an animal model that fully recapitulates NAFLD, we demonstrate that these compounds are ineffective against age-associated NAFLD-induced HCC. Video Abstract.

Redox and Epigenetics in Human Pluripotent Stem Cells Differentiation.

Significance: Since their discovery, induced pluripotent stem cells (iPSCs) had generated considerable interest in the scientific community for their great potential in regenerative medicine, disease modeling, and cell-based therapeutic approach, due to their unique characteristics of self-renewal and pluripotency. Recent Advances: Technological advances in iPSC genome-wide epigenetic profiling led to the elucidation of the epigenetic control of cellular identity during nuclear reprogramming. Moreover, iPSC physiology and metabolism are tightly regulated by oxidation-reduction events that mainly occur during the respiratory chain. In theory, iPSC-derived differentiated cells would be ideal for stem cell transplantation as autologous cells from donors, as the risks of rejection are minimal. Critical Issues: However, iPSCs experience high oxidative stress that, in turn, confers a high risk of increased genomic instability, which is most often linked to DNA repair deficiencies. Genomic instability has to be assessed before iPSCs can be used in therapeutic designs. Future Directions: This review will particularly focus on the links between redox balance and epigenetic modifications-in particular based on the histone variant macroH2A1-that determine DNA damage response in iPSCs and derived differentiated cells, and that might be exploited to decrease the teratogenic potential on iPSC transplantation. Antioxid. Redox Signal. 34, 335-349.

Milk thistle seed cold press oil attenuates markers of the metabolic syndrome in a mouse model of dietary-induced obesity.

Milk thistle cold press oil (MTO) is an herbal remedy derived from Silybum marianum which contains a low level of silymarin and mixture of polyphenols and flavonoids. The effect of MTO on the cardiovascular and metabolic complications of obesity was studied in mice that were fed a high-fat diet (HFD) for 20 weeks and treated with MTO for the final 8 weeks of the diet. MTO treatment attenuated HFD-induced obesity, fasting hyperglycemia, hypertension, and induced markers of mitochondrial fusion and browning of white adipose. Markers of inflammation were also attenuated in both adipose and the liver of MTO-treated mice. In addition, MTO resulted in the improvement of liver fibrosis. These results demonstrate that MTO has beneficial actions to attenuate dietary obesity-induced weight gain, hyperglycemia, hypertension, inflammation, and suggest that MTO supplementation may prove beneficial to patients exhibiting symptoms of metabolic syndrome. PRACTICAL APPLICATIONS: Natural supplements are increasingly being considered as potential therapies for many chronic cardiovascular and metabolic diseases. Milk thistle cold press oil (MTO) is derived from Silybum marianum which is used as a dietary supplement in different parts of the world. The results of the present study demonstrate that MTO supplementation normalizes several metabolic and cardiovascular complications arising from dietary-induced obesity. MTO supplementation also had anti-inflammatory actions in the adipose as well as the liver. These results suggest that supplementation of MTO into the diet of obese individuals may afford protection against the worsening of cardiovascular and metabolic disease and improve inflammation and liver fibrosis.

Cold Press Pomegranate Seed Oil Attenuates Dietary-Obesity Induced Hepatic Steatosis and Fibrosis through Antioxidant and Mitochondrial Pathways in Obese Mice.

AIM: Obesity is associated with metabolic syndrome, hypertension, dyslipidemia, nonalcoholic fatty liver disease (NAFLD), and type 2 diabetes. In this study, we investigated whether the dietary supplementation of pomegranate seed oil (PSO) exerted a protective effect on liver lipid uptake, fibrosis, and mitochondrial function in a mouse model of obesity and insulin resistance. METHOD: In this in vivo study, eight-week-old C57BL/6J male mice were fed with a high fat diet (HFD) for 24 weeks and then were divided into three groups as follows: group (1) Lean; group (n = 6) (2) HF diet; group (n = 6) (3) HF diet treated with PSO (40 mL/kg food) (n = 6) for eight additional weeks starting at 24 weeks. Physiological parameters, lipid droplet accumulation, inflammatory biomarkers, antioxidant biomarkers, mitochondrial biogenesis, insulin sensitivity, and hepatic fibrosis were determined to examine whether PSO intervention prevents obesity-associated metabolic syndrome. RESULTS: The PSO group displayed an increase in oxygen consumption, as well as a decrease in fasting glucose and blood pressure (p < 0.05) when compared to the HFD-fed mice group. PSO increased both the activity and expression of hepatic HO-1, downregulated inflammatory adipokines, and decreased hepatic fibrosis. PSO increased the levels of thermogenic genes, mitochondrial signaling, and lipid metabolism through increases in Mfn2, OPA-1, PRDM 16, and PGC1α. Furthermore, PSO upregulated obesity-mediated hepatic insulin receptor phosphorylation Tyr-972, p-IRB tyr1146, and pAMPK, thereby decreasing insulin resistance. CONCLUSIONS: These results indicated that PSO decreased obesity-mediated insulin resistance and the progression of hepatic fibrosis through an improved liver signaling, as manifested by increased insulin receptor phosphorylation and thermogenic genes. Furthermore, our findings indicate a potential therapeutic role for PSO in the prevention of obesity-associated NAFLD, NASH, and other metabolic disorders.

Non-competitive heme oxygenase-1 activity inhibitor reduces non-small cell lung cancer glutathione content and regulates cell proliferation.

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related death mainly due to its high metastatic rate. Impairment of redox homeostasis mechanisms has been previously described in NSCLC and is associated with the disease itself as well as with comorbidities such as smoking. The aim of the present in vitro study was to evaluate the effect of selective and non-competitive inhibition of heme oxygenase-1 (HO-1) on cancer redox homeostasis with particular regards to glutathione (GSH) metabolism related enzymes. NSCLC cell line (A549) was treated with the HO-1 activity inhibitor VP13/47 (10 µM) and we further evaluated cell viability, apoptosis, mitochondrial dysfunction and oxidative stress. Our results showed that VP13/47 significantly reduced HO-1 expression and total HO activity thus, resulting in a significant reduction of cell viability, proliferation and increased apoptosis, mitochondrial dysfunction and oxidative stress. Consistently with increased oxidative stress, we also showed that reduced GSH was significantly decreased and such effect was also accompanied by a significant downregulation of the enzymes involved in its biosynthesis. Taken all together our results show that selective HO-1 inhibition significantly impairs NSCLC progression and may represent a possible pharmacological strategy for new chemotherapy agents.

Ginseng and heme oxygenase-1: The link between an old herb and a new protective system.

Ginseng is an ancient herb, belonging to Asian traditional medicine, that has been considered as a restorative to enhance vitality for centuries. It has been demonstrated that the antioxidant action of ginseng may be mediated through activation of different cellular signaling pathways involving the heme oxygenase (HO) system. Several compounds derived from ginseng have been studied for their potential role in brain, heart and liver protection, and the Nrf2 pathway seems to be the most affected by these natural molecules to exert this effect. Ginseng is also popularly used in cancer patients therapy for the demonstrated capability to defend tissues from chemotherapy-induced damage. Reported results suggest that the effect of ginseng is primarily associated with ROS scavenging, mainly exerted through the activation of Nrf2 pathway, and the consequent induction of HO-1 levels. This review aims to discuss the connection between the antioxidant properties of ginseng and the activation of the HO system, as well as to outline novel therapeutic applications of this medicinal plant to human health.

Heme Oxygenase-1 Inhibition Sensitizes Human Prostate Cancer Cells towards Glucose Deprivation and Metformin-Mediated Cell Death.

High levels of heme oxygenase (HO)-1 have been frequently reported in different human cancers, playing a major role in drug resistance and regulation of cancer cell redox homeostasis. Metformin (MET), a drug widely used for type 2 diabetes, has recently gained interest for treating several cancers. Recent studies indicated that the anti-proliferative effects of metformin in cancer cells are highly dependent on glucose concentration. The present work was directed to determine whether use of a specific inhibitor of HO-1 activity, alone or in combination with metformin, affected metastatic prostate cancer cell viability under different concentrations of glucose. MTT assay and the xCELLigence system were used to evaluate cell viability and cell proliferation in DU145 human prostate cancer cells. Cell apoptosis and reactive oxygen species were analyzed by flow cytometry. The activity of HO-1 was inhibited using a selective imidazole-based inhibitor; genes associated with antioxidant systems and cell death were evaluated by qRT-PCR. Our study demonstrates that metformin suppressed prostate cancer growth in vitro and increased oxidative stress. Disrupting the antioxidant HO-1 activity, especially under low glucose concentration, could be an attractive approach to potentiate metformin antineoplastic effects and could provide a biochemical basis for developing HO-1-targeting drugs against solid tumors.

Protective Effects of Caffeic Acid Phenethyl Ester (CAPE) and Novel Cape Analogue as Inducers of Heme Oxygenase-1 in Streptozotocin-Induced Type 1 Diabetic Rats.

Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease resulting in the destruction of insulin producing ß-cells of the pancreas, with consequent insulin deficiency and excessive glucose production. Hyperglycemia results in increased levels of reactive oxygen species (ROS) and nitrogen species (RNS) with consequent oxidative/nitrosative stress and tissue damage. Oxidative damage of the pancreatic tissue may contribute to endothelial dysfunction associated with diabetes. The aim of the present study was to investigate if the potentially protective effects of phenethyl ester of caffeic acid (CAPE), a natural phenolic compound occurring in a variety of plants and derived from honeybee hive propolis, and of a novel CAPE analogue, as heme oxygenase-1 (HO-1) inducers, could reduce pancreatic oxidative damage induced by excessive amount of glucose, affecting the nitric oxide synthase/dimethylarginine dimethylaminohydrolase (NOS/DDAH) pathway in streptozotocin-induced type 1 diabetic rats. Our data demonstrated that inducible nitric oxide synthase/gamma-Glutamyl-cysteine ligase (iNOS/GGCL) and DDAH dysregulation may play a key role in high glucose mediated oxidative stress, whereas HO-1 inducers such as CAPE or its more potent derivatives may be useful in diabetes and other stress-induced pathological conditions.

Mesenteric lymph nodes as alternative site for pancreatic islet transplantation in a diabetic rat model.

BACKGROUND: Islet transplantation has progressively become a safe alternative to pancreas transplantation for the treatment of type 1 diabetes. However, the long-term results of islet transplantation could be significantly increased by improving the quality of the islet isolation technique even exploring alternative islet transplantation sites to reduce the number of islets required to mitigate hyperglycemia. The goal of the study was to test the lymph node as a suitable anatomical location for islet engraftment in a rodent model. METHODS: Forty Lewis rats, 6-8 weeks old, body weight 250-300 g, have been used as islet donors and recipients in syngeneic islet transplantation experiments. Ten rats were rendered diabetic by one injection of 65 mg/Kg of streptozotocin. After pancreas retrieval from non diabetic donors, islet were isolated and transplanted in the mesenteric lymph nodes of 7 diabetic rats. Rats were followed for 30 days after islet transplantation. RESULTS: A total of 7 islet transplantations in mesenteric lymph nodes have been performed. Two rats died 24 and 36 h after transplantation due to complications. No transplanted rat acquired normal glucose blood levels and insulin independence after the transplantation. However, the mean blood levels of glycemia were significantly lower in transplanted rats compared with diabetic rats (470.4 mg/dl vs 605 mg/dl, p 0.04). Interestingly, transplanted rats have a significant weight increase after transplantation compared to diabetic rats (mean value 295 g in transplanted rats vs 245 g in diabetic rats, p < 0.05), with an overall improvement of social activities and health. Immunohistochemical analysis of the 5 mesenteric lymph nodes of transplanted rats demonstrated the presence of living islets in one lymph node. CONCLUSIONS: Although islet engraftment in lymph nodes is possible, islet transplantation in lymph nodes in rats resulted in few improvements of glucose parameters.

Beneficial Effects of Pomegranate Peel Extract and Probiotics on Pre-adipocyte Differentiation.

The beneficial effects of pomegranate are due to the ellagitannins and anthocyanins content, which are protective toward a wide variety of diseases including inflammatory diseases. Many investigators have reported that pomegranate waste (peel and seeds) extracts, made from waste product of industrial processing, show free radical scavenger and a potent antioxidant capacity. Pomegranate extracts (PEs) were also reported to possess noteworty antibacterial, antiviral, hypolipidemic, and anti-inflammatory bioactivities thanks to the polyphenolic compounds content, which includes punicalagins, gallic acid, and ellagic acid derivatives. The focus of the present manuscript was to study the prebiotic potentiality of a PE, soluble in water, and characterized through HPLC-PDA-ESI/MS n for its phenolic content. Moreover, since it has been reported that pomegranate extracts decreased the level of lipids in the blood and that a number of probiotic strains have been shown to affect adipogenesis in cell culture, this study was also performed to test the in vitro effects of PE and probiotic L. rhamnosus GG ATCC 53103 strain (LGG) on 3T3-L1 cell line. PE and probiotics substantially reduced the triglyceride content and intracellular lipid increase, compared to the control group. However, the combination treatment of PE and LGG filtered spent broth (SB) was the most effective in reducing triglyceride content and intracellular lipid accumulation. The mRNA expression levels of the main transcriptional factors implicated in adipocyte differentiation were substantially lower in 3T3-L1 cells treated with PE and LGG filtered SB. These results evidenced that a synergistic effect of probiotics and polyphenols contained in PE may affect in vitro adipogenesis and may contribute in development of new nutraceutical/probiotic-based remedies to prevent and to treat obesity.

Heme Oxygenase Inhibition Sensitizes Neuroblastoma Cells to Carfilzomib.

Neuroblastoma (NB) is an embryonic malignancy affecting the physiological development of adrenal medulla and paravertebral sympathetic ganglia in early infancy. Proteasome inhibitors (PIs) (i.e., carfilzomib (CFZ)) may represent a possible pharmacological treatment for solid tumors including NB. In the present study, we tested the effect of a novel non-competitive inhibitor of heme oxygenase-1 (HO-1), LS1/71, as a possible adjuvant therapy for the efficacy of CFZ in neuroblastoma cells. Our results showed that CFZ increased both HO-1 gene expression (about 18-fold) and HO activity (about 8-fold), following activation of the ER stress pathway. The involvement of HO-1 in CFZ-mediated cytotoxicity was further confirmed by the protective effect of pharmacological induction of HO-1, significantly attenuating cytotoxicity. In addition, HO-1 selective inhibition by a specific siRNA increased the cytotoxic effect following CFZ treatment in NB whereas SnMP, a competitive pharmacological inhibitor of HO, showed no changes in cytotoxicity. Our data suggest that treatment with CFZ produces ER stress in NB without activation of CHOP-mediated apoptosis, whereas co-treatment with CFZ and LS1/71 led to apoptosis activation and CHOP expression induction. In conclusion, our study showed that treatment with the non-competitive inhibitor of HO-1, LS1 / 71, increased cytotoxicity mediated by CFZ, triggering apoptosis following ER stress activation. These results suggest that PIs may represent a possible pharmacological treatment for solid tumors and that HO-1 inhibition may represent a possible strategy to overcome chemoresistance and increase the efficacy of chemotherapic regimens.

Ablation of soluble epoxide hydrolase reprogram white fat to beige-like fat through an increase in mitochondrial integrity, HO-1-adiponectin in vitro and in vivo.

We have shown that epoxyeicosatrienoic acids (EETs), specifically 11,12- and 14,15-EETs, reduce adipogenesis in human mesenchymal stem cells and mouse preadipocytes (3T-3L1). In this study, we explore the effects of soluble epoxide hydrolase (sEH) deletion on various aspects of adipocyte-function, including programing for white vs. beige-like fat, and mitochondrial and thermogenic gene-expressions. We further hypothesize that EETs and heme-oxygenase 1 (HO-1) form a synergistic, functional module whose effects on adipocyte and vascular function is greater than the effects of sEH deletion alone. In in vitro studies, we examined the effect of sEH inhibitors on MSC-derived adipocytes. MSC-derived adipocytes exposed to AUDA, an inhibitor of sEH, exhibit an increased number of small and healthy adipocytes, an effect reproduced by siRNA for sEH. in vivo studies indicate that sEH deletion results in a significant decrease in adipocyte size, inflammatory adipokines NOV, TNFα, while increasing adiponectin (p < 0.05). These findings are associated with a decrease in body weight (p < 0.05), and visceral fat (p < 0.05). Importantly, sEH deletion was associated with a significant increase in Mfn1, COX 1, UCP1 and adiponectin (p < 0.03). sEH deletion was manifested by a significant increase in EETs isomers 5,6-EET, 8,9-EET, 11,12-EET, and 14,15-EET and an increased EETs/DHETEs ratio. Notably, activation of HO-1 gene expression further increased the levels of EETs, suggesting that the antioxidant HO-1 system protects EETs from degradation by ROS. These results are novel in that sEH deletion, while increasing EET levels, resulted in reprograming of white fat to express mitochondrial and thermogenic genes, a phenotype characteristic of beige-fat. Thus, EETs agonist(s) and sEH inhibitors may have therapeutic potential in the treatment of metabolic syndrome and obesity.

Metformin: A Bridge between Diabetes and Prostate Cancer.

Prostate cancer (PCa) has become the most frequent type of cancer in men. Recent data suggest that diabetic patients taking metformin have a lower incidence of certain cancer, including PCa. Metformin is the most common drug used in type II diabetes mellitus; its use has been shown to lower the incidence of several cancers, although there are ambiguous data about the anticancer activity of metformin. A large number of studies examined the potential antineoplastic mechanism of metformin although it is not still completely understood. This review summarizes the literature concerning the effects of metformin on PCa cells, highlighting its numerous mechanisms of action through which it can act. We analyze the possible causes of the discordances regarding the impact of metformin on risk of PCa; we discuss the latest findings in this field, suggesting that metformin may have a future role in the management of PCa both as monotherapy and in combination with other drugs.

Novel Caffeic Acid Phenethyl Ester (Cape) Analogues as Inducers of Heme Oxygenase-1.

BACKGROUND: Heme Oxygenase-1 (HO-1) is a metabolic enzyme strongly involved in processes including cytoprotection, modulation of inflammatory response, anti-oxidative functions, regulation of cellular proliferation, angiogenesis, cardiovascular homeostasis, and immuno-modulation. HO-1 induction and/or activation is able to counterbalance, at least in part, oxidative stress and inflammation. For this reason, HO-1 can be regarded as an attractive target to ameliorate different stress-related pathologies. Caffeic acid phenethyl ester, a natural polyphenolic compound, behaves as HO-1 inducer and possesses a plethora of beneficial effects under oxidative stress conditions. OBJECTIVES: A small focused series of caffeic acid phenethyl ester (Cape) analogues was designed and synthesized with the aim of obtaining more potent HO-1 inducers. METHOD: The capacity of these new compounds to modify the levels of HO-1 was evaluated in human mesenchymal stem cells (hMSCs) derived from bone marrow. RESULTS AND CONCLUSION: Some of tested compounds were found to be good HO-1 inducers and 3-(3,4- dihydroxyphenyl)-(2E)-2-propenoic acid 2-(3,4-dimethoxyphenyl) ethyl ester (VP961) was the most potent. VP961 tested to measure HO-1 protein expression and HO activity in in vitro system resulted more potent than the parent compound Cape both as inducer and as direct activator of the enzyme. VP961, selected as lead compound for further characterization, showed antioxidant properties in a model of H2O2-mediated ROS production and cytoprotective effects in a model of H2O2 cells viability impairment. To the best of our knowledge, VP961 is the first known compound able to activate directly HO-1 enzyme and to induce at the same time its protein expression.

Therapeutic Efficacy of Stem Cells Transplantation in Diabetes: Role of Heme Oxygenase.

The growing data obtained from in vivo studies and clinical trials demonstrated the benefit of adult stem cells transplantation in diabetes; although an important limit is represented by their survival after the transplant. To this regard, recent reports suggest that genetic manipulation of stem cells prior to transplantation can lead to enhanced survival and better engraftment. The following review proposes to stimulate interest in the role of heme oxygenase-1 over-expression on transplantation of stem cells in diabetes, focusing on the clinical potential of heme oxygenase protein and activity to restore tissue damage and/or to improve the immunomodulatory properties of transplanted stem cells.