Red Grape Polyphenol Oral Administration Improves Immune Response in Women Affected by Nickel-Mediated Allergic Contact Dermatitis.

BACKGROUND: Our previous findings demonstrated that in vitro supplementation of polyphenols, extracted from seeds of red grape (Nero di Troia cultivar), to peripheral lymphomonocytes from patients affected by allergic contact dermatitis (ACD) to nickel (Ni) could reduce the release of proinflammatory cytokines and nitric oxide (NO), while increasing the levels of interleukin (IL)-10, an anti-inflammatory cytokine. OBJECTIVE: To assess whether an intervention with oral administration of polyphenols leads to a reduction of peripheral biomarkers in ACD patients. METHODS: At T0, 25 patients affected by ACD to Ni were orally administered with 300 mg polyphenols prodie extracted from seeds of red grape (Nero di Troia cultivar) (NATUR-OX®) for 3 months (T1). The other 25 patients affected by ACD to Ni received placebo only for the same period of time. Serum biomarkers were analyzed at T0 and T1. In both groups, seven dropouts were recorded. RESULTS: At T1 in comparison to T0, in treated patients, values of interferon-γ, IL-4, IL-17, pentraxin 3 and NO decreased, while IL-10 levels increased when compared with T0 values. Conversely, in placebo- treated patients, no modifications of biomarkers were evaluated at T1. CONCLUSION: Present laboratory data rely on the anti-oxidant, anti-inflammatory and anti-allergic properties of polyphenols.

Peripheral Immunosenescence and Central Neuroinflammation: A Dangerous Liaison - A Dietary Approach.

BACKGROUND & OBJECTIVES: In old people, both innate and adaptive immune responses are impaired, thus leading to a condition of systemic inflamm-ageing, even including the involvement of the central nervous system (CNS). AIMS: Here, main mechanisms of the immune ageing and neuro-inflammation will be discussed along with the dietary approaches for the modulation of age related diseases. DISCUSSION: Neuroinflammation is caused by the passage of inflammatory mediators through the brain blood barrier to CNS. Then, in the brain, antigenic stimulation of microglia and/or its activation by peripheral cytokines lead to a robust production of free radicals with another wave of proinflammatory cytokines which, in turn, causes massive neuronal damage. Also, infiltrating T cells [T helper (h) and T cytotoxic cells] contribute to neuronal damage. Additionally, a peripheral imbalance between inflammatory Th17 cells and anti-inflammatory T regulatory cells seems to be prevalent in the aged brain, thus leading to a proinflammatory profile. Alzheimer's disease, Parkinson's disease and multiple sclerosis will be described as typical neurodegenerative diseases. Finally, modulation of the immune response thanks to the anti-oxidant and anti-inflammatory effects exerted by dietary products and nutraceuticals in ageing will be discussed. Special emphasis will be placed on polyunsaturated fatty acids, polyphenols, micronutrients and pre-probiotics and synbiotics. CONCLUSION: Ageing is characterized by an imbalance subversion of the immune system with a condition of inflamm-ageing. Neuroinflammation and neurodegenerative diseases seem to be a central manifestation of a peripheral perturbation of the immune machinery. Dietary products and nutraceuticals may lead to a down-regulation of the oxidative and pro-inflammatory profile in ageing.

Metformin Impairs Glutamine Metabolism and Autophagy in Tumour Cells.

Metformin has been shown to inhibit glutaminase (GLS) activity and ammonia accumulation thereby reducing the risk of hepatic encephalopathy in type 2 diabetic patients. Since tumour cells are addicted to glutamine and often show an overexpression of glutaminase, we hypothesize that the antitumoral mechanism of metformin could be ascribed to inhibition of GLS and reduction of ammonia and ammonia-induced autophagy. Our results show that, in different tumour cell lines, micromolar doses of metformin prevent cell growth by reducing glutamate, ammonia accumulation, autophagy markers such as MAP1LC3B-II and GABARAP as well as degradation of long-lived proteins. Reduced autophagy is then accompanied by increased BECN1/BCL2 binding and apoptotic cell death. Interestingly, GLS-silenced cells reproduce the effect of metformin treatment showing reduced MAP1LC3B-II and GABARAP as well as ammonia accumulation. Since metformin is used as adjuvant drug to increase the efficacy of Cisplatin-based neoadjuvant chemotherapy, we co-treated tumour cells with micromolar doses of metformin in the presence of cisplatin observing a marked reduction of MAP1LC3B-II and an increase of caspase 3 cleavage. In conclusion, our work demonstrates that the anti-tumoral action of metformin is due to the inhibition of glutaminase and autophagy and could be used to improve the efficacy of chemotherapy.

Olive Leaf Extracts Act as Modulators of the Human Immune Response.

BACKGROUND: Olive tree leaves have been used in the Mediterranean area as traditional medicine in virtue of their healthy effects. Olive leaf extracts (OLEs) contain higher amounts of polyphenols than those detected in the extra virgin olive oil and fruit. Several lines of evidence support the cardioprotective, anti-oxidant and anti-inflammatory activities exerted by OLEs. METHODS: Peripheral blood mononuclear cells from twenty-five healthy donors were cultured in the presence of 3 µg of two OLE extracts, extract A (resuspended in water) and extract B (resuspended in 70% ethanol). After harvesting, cell pellets were used for cytofluorimetric phenotyping, while supernatants were assayed for cytokine release by means of ELISA. Furthermore, in the same supernatants nitric oxide (NO) content was determined. RESULTS: Both extracts, but especially extract A, increased absolute numbers of CD8+ and natural killer (NK) cells. In addition, an increased production of interferon (IFN)-γ by both extracts as an expression of T helper (h)1 activation was observed. Finally, both extracts enhanced NO release. CONCLUSION: OLEs, and mostly extract A, are able to in vitro modify healthy human immune response by increasing IFN-γ production which seems to be associated to the higher absolute numbers of CD8+ and NK cells and this may suggest a reinforcement of the anti-tumor activity. Furthermore, increased levels of NO may indicate the potential cardioprotective effects exerted by OLEs in virtue of their vasodilation dependent activity. Finally, OLEs are able to maintain the equilibrium between T regulatory cells and Th17 cells as evidenced by unmodified levels of interleukin (IL)-IL-10 and IL-17, respectively. In the light of these results, OLEs are potential therapeutic compounds for the treatment of chronic inflammatory disease, also preventing cardiovascular event outcome.

In vitro Effects of Polyphenols on the Peripheral Immune Responses in Nickel-sensitized Patients.

BACKGROUND: Nickel (Ni) is a metal largely present in the environment and prolonged exposure to it may lead to multiple pathological conditions in human subjects. Among these, the most frequent is allergic contact dermatitis. METHODS: Peripheral blood mononuclear cells isolated from 25 patients with Ni-dependent contact dermatitis were evaluated in terms of cytokine release and nitric oxide (NO) production in the presence or absence of two doses (3 and 5 µg, respectively) of polyphenols. RESULTS: Polyphenols were able to reduce the increased release of interferon-γ and interleukin (IL)-4, while maintaining the equilibrium between IL-10 and IL-17. At the same time, exaggerated release of NO was reduced by polyphenol supplementation. CONCLUSION: In view of their anti-inflammatory activities, polyphenols may represent a potential therapeutic tool to treat Ni-sensitized patients.

Pathology and function of conduction tissue in Fabry disease cardiomyopathy.

BACKGROUND: Cardiac arrhythmias are common in Fabry disease (FD) and may occur in prehypertrophic cardiomyopathy suggesting an early compromise of conduction tissue (CT). Therefore, FD X-linked and CT may be variously involved in male and female patients with FD cardiomyopathy, affecting CT function. METHODS AND RESULTS: Among 74 patients with endomyocardial biopsy diagnosis of FD cardiomyopathy, 13 (6 men; 7 women; mean age, 50.1±13.5 years; maximal wall thickness, 16.7±3.7 mm) had CT included in histological specimens and 6 also at electron microscopy. CT glycolipid infiltration was defined as focal, moderate, extensive, or massive, if involved ≤30%, ≤50%, >50%, or 100% of cells; identified as loosely arranged small myocytes positive to HCN4 immunostaining, supplied by a centrally placed thick-walled arteriole. CT involvement was correlated with age, sex, and α-Gal gene mutation. CT function was evaluated by electrophysiological study and arrhythmias at Holter registration. CT infiltration was focal/moderate in 4 women with no arrhythmias and normal electrophysiological study, extensive in 3 women with atrial or ventricular arrhythmias and short HV interval, and massive in 6 men with atrial fibrillation or ventricular arrhythmias and short HV. Short PR/AH with increased refractoriness was additionally found in 3 patients with extensive/massive CT infiltration. A male patient with the shortest HV presented infra-Hissian block during decremental atrial stimulation. There was no correlation with age, maximal wall thickness, and type of gene mutation. CONCLUSIONS: CT infiltration in FD cardiomyopathy is constant in men and variable in women because of skewed X-chromosome inactivation; its extensive/massive involvement causes accelerated conduction with prolonged refractoriness and electric instability.

Selenium- and zinc-deficient cardiomyopathy in human intestinal malabsorption: preliminary results of selenium/zinc infusion.

AIMS: Patients with intestinal malabsorption may develop cardiac dysfunction the origin of which is often unclear. We sought to investigate the pathogenesis of dilated cardiomyopathy in human malabsorption. METHODS AND RESULTS: Eighteen patients with intestinal bypass as treatment for severe obesity and cardiomyopathy underwent endomyocardial biopsy. Biopsies were processed by histology, electron microscopy, polymerase chain reaction (PCR) for cardiotropic viruses, instrumental neutron activation analysis (INAA) of 33 myocardial trace elements, and assessment of glutathione peroxidase (GPX) activity and LC3-II expression. Histology and electron microscopy showed hypertrophy/degeneration of cardiomyocytes with pronounced cell autophagy and high expression of LC3-II. PCR was negative for viral genomes. INAA showed severe myocardial selenium (Se) and zinc (Zn) deficiency and reduced GPX activity vs. both patients with idiopathic dilated cardiomyopathy and normal controls. Se and Zn were added to antifailing heart therapy in 10 patients (group A1) agreeing to a control biopsy, and the response was compared with that of 8 patients (group A2) on supportive therapy alone. After 6 months, myocardial normalization of Se, Zn, LC3-II, and GPX in group A1 was associated with recovery of cardiomyocyte degeneration and autophagy, and significant improvement in cardiac dimension and function, that remained unchanged in group A2. CONCLUSION: A reversible Se- and Zn-deficient cardiomyopathy may occur in patients with intestinal malabsorption. It is characterized by decline of myocardial antioxidant reserve, oxidative damage of cell membranes, and enhanced cell autophagy.

REN: a novel, developmentally regulated gene that promotes neural cell differentiation.

Expansion and fate choice of pluripotent stem cells along the neuroectodermal lineage is regulated by a number of signals, including EGF, retinoic acid, and NGF, which also control the proliferation and differentiation of central nervous system (CNS) and peripheral nervous system (PNS) neural progenitor cells. We report here the identification of a novel gene, REN, upregulated by neurogenic signals (retinoic acid, EGF, and NGF) in pluripotent embryonal stem (ES) cells and neural progenitor cell lines in association with neurotypic differentiation. Consistent with a role in neural promotion, REN overexpression induced neuronal differentiation as well as growth arrest and p27Kip1 expression in CNS and PNS neural progenitor cell lines, and its inhibition impaired retinoic acid induction of neurogenin-1 and NeuroD expression. REN expression is developmentally regulated, initially detected in the neural fold epithelium of the mouse embryo during gastrulation, and subsequently throughout the ventral neural tube, the outer layer of the ventricular encephalic neuroepithelium and in neural crest derivatives including dorsal root ganglia. We propose that REN represents a novel component of the neurogenic signaling cascade induced by retinoic acid, EGF, and NGF, and is both a marker and a regulator of neuronal differentiation.