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Sourdough Bread Made from Wheat and Nontoxic Flours and Started with Selected Lactobacilli Is Tolerated in Celiac Sprue Patients

ABSTRACT This work was aimed at producing a sourdough bread that is tolerated by celiac sprue (CS) patients. Selected sourdough lactobacilli had specialized peptidases capable of hydrolyzing Pro-rich peptides, including the 33-mer peptide, the most potent inducer of gut-derived human T-cell lines in CS patients. This epitope, the most important in CS, was hydrolyzed completely after treatment with cells and their cytoplasmic extracts (CE). A sourdough made from a mixture of wheat (30%) and nontoxic oat, millet, and buckwheat flours was started with lactobacilli. After 24 h of fermentation, wheat gliadins and low-molecular-mass, alcohol-soluble polypeptides were hydrolyzed almost totally. Proteins were extracted from sourdough and used to produce a peptic-tryptic digest for in vitro agglutination tests on K 562(S) subclone cells of human origin. The minimal agglutinating activity was ca. 250 times higher than that of doughs chemically acidified or started with bakers yeast. Two types of bread, containing ca. 2 g of gluten, were produced with bakers yeast or lactobacilli and CE and used for an in vivo double-blind acute challenge of CS patients. Thirteen of the 17 patients showed a marked alteration of intestinal permeability after ingestion of bakers yeast bread. When fed the sourdough bread, the same 13 patients had values for excreted rhamnose and lactulose that did not differ significantly from the baseline values. The other 4 of the 17 CS patients did not respond to gluten after ingesting the bakers yeast or sourdough bread. These results showed that a bread biotechnology that uses selected lactobacilli, nontoxic flours, and a long fermentation time is a novel tool for decreasing the level of gluten intolerance in humans.

Protocatechuic acid induces antioxidant/detoxifying enzyme expression through JNK-mediated Nrf2 activation in murine macrophages

Protocatechuic acid (PCA) is a main metabolite of anthocyanins, whose daily intake is much higher than that of other polyphenols. PCA has biological effects, e.g., it induces the antioxidant/detoxifying enzyme gene expression. This study was aimed at defining the molecular mechanism responsible for PCA-induced over-expression of glutathione (GSH) peroxidase (GPx) and GSH reductase (GR) in J774 A.1 macrophages. New evidence is provided that PCA increases GPx and GR expression by inducing C-JUN NH(2)-terminal kinase (JNK)-mediated phosphorylation of Nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2). RNA and proteins were extracted from cells treated with PCA (25 μM) for different time points. Quantitative real-time polymerase chain reaction and immunoblotting analyses showed a rapid increase in mRNA (>60%) and protein (>50%) for both the enzymes. This was preceded by the up-regulation of Nrf2, in terms of mRNA and protein, and by its significant activation as assessed by increased Nrf2 phosphorylation and nuclear translocation (+60%). By using specific kinase inhibitors and detecting the activated form, we showed that JNK was the main upstream kinase responsible for Nrf2 activation. Convincing evidence is provided of a causal link between PCA-induced Nrf2 activation and increased enzyme expression. By silencing Nrf2 and using a JNK inhibitor, enzyme enhancement was counteracted. Finally, with the ChIP assay, we demonstrated that PCA-activated Nrf2 specifically bound ARE sequences in enzyme gene promoters. Our study demonstrates for the first time that PCA improves the macrophage endogenous antioxidant potential by a mechanism in which JNK-mediated Nrf2 activation plays an essential role. This knowledge could contribute to novel diet-based approaches aimed at counteracting oxidative injury by reinforcing endogenous defences.

Oxidised LDL up-regulate CD36 expression by the Nrf2 pathway in 3T3-L1 preadipocytes

The effect of oxLDL on CD36 expression has been assessed in preadipocytes induced to differentiate. Novel evidence is provided that oxLDL induce a peroxisome proliferator‐activated receptor γ‐independent CD36 overexpression, by up‐regulating nuclear factor erythroid 2 (NF‐E2)‐related factor 2 (Nrf2). The nuclear translocation of Nrf2 appeared to depend on PKC pathway activation. In adipocytes, the CD36 up‐regulation may indicate a compensation mechanism to meet the demand of excess oxLDL and oxidised lipids in blood, reducing the risk of atherogenesis. Besides strengthening the hypothesis that oxLDL can contribute to the onset of insulin‐resistance, data herein presented highlight the significance of oxLDL‐induced CD36 overexpression within the cellular defence response.

Oxidized LDL impair adipocyte response to insulin by activating serine/threonine kinases

Oxidized LDL (oxLDL) increase in patients affected by type-2 diabetes, obesity, and metabolic syndrome. Likewise, insulin resistance, an impaired responsiveness of target tissues to insulin, is associated with those pathological conditions. To investigate a possible causal relationship between oxLDL and the onset of insulin resistance, we evaluated the response to insulin of 3T3-L1 adipocytes treated with oxLDL. We observed that oxLDL inhibited glucose uptake (−40%) through reduced glucose transporter 4 (GLUT4) recruitment to the plasma membrane (−70%), without affecting GLUT4 gene expression. These findings were associated to the impairment of insulin signaling. Specifically, in oxLDL-treated cells insulin receptor (IR) substrate-1 (IRS-1) was highly degraded likely because of the enhanced Ser307phosphorylation. This process was largely mediated by the activation of the inhibitor of κB-kinase β (IKKβ) and the c-Jun NH2-terminal kinase (JNK). Moreover, the activation of IKKβ positively regulated the nuclear content of nuclear factor κB (NF-κB), by inactivating the inhibitor of NF-κB (IκBα). The activated NF-κB further impaired per se GLUT4 functionality. Specific inhibitors of IKKβ, JNK, and NF-κB restored insulin sensitivity in adipocytes treated with oxLDL. These data provide the first evidence that oxLDL, by activating serine/threonine kinases, impaired adipocyte response to insulin affecting pathways involved in the recruitment of GLUT4 to plasma membranes (PM). This suggests that oxLDL might participate in the development of insulin resistance.

Protocatechuic acid activates key components of insulin signaling pathway mimicking insulin activity

SCOPE Insulin resistance represents an independent risk factor for metabolic and cardiovascular diseases. Researchers have been interested in identifying active harmless compounds, as many insulin-sensitizing drugs have shown unwanted side-effects. It has been demonstrated that anthocyanins and one of their representative metabolites, protocatechuic acid (PCA), ameliorate hyperglycemia, and insulin sensitivity. This study investigated the mechanism of action of PCA responsible for the glucose uptake upregulation. METHODS AND RESULTS In human visceral adipocytes, PCA stimulated insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation (+40% with respect to untreated cells) and the downstream events, i.e. phosphoinositide 3-kinase binding to IRS-1 and Akt phosphorylation (+100%, +180%, respectively, with respect to untreated cells). The insulin-like activity of PCA seemed to be mediated by insulin receptor since by inhibiting its autophosphorylation, the PCA effects were completely abolished. Furthermore, PCA was able to activate adenosine monophosphate-activated protein kinase, a serine/threonine kinase whose activation elicits insulin-sensitizing effects. CONCLUSION This study showed that PCA stimulates the insulin signaling pathway in human adipocytes increasing GLUT4 translocation and glucose uptake. Decreasing insulin resistance is a most desirable aim to be reached for an effective therapeutic/preventive action against metabolic syndrome and type 2 diabetes. Identifying specific food/food components able to improve glucose metabolism can offer an attractive, novel, and economical strategy.

Protocatechuic Acid Prevents oxLDL-Induced Apoptosis by Activating JNK/Nrf2 Survival Signals in Macrophages

Protocatechuic acid (PCA), one of the main metabolites of complex polyphenols, exerts numerous biological activities including antiapoptotic, anti-inflammatory, and antiatherosclerotic effects. Oxidised LDL have atherogenic properties by damaging arterial wall cells and inducing p53-dependent apoptosis in macrophages. This study was aimed at defining the molecular mechanism responsible for the protective effects of PCA against oxidative and proapoptotic damage exerted by oxLDL in J774 A.1 macrophages. We found that the presence of PCA in cells treated with oxLDL completely inhibited the p53-dependent apoptosis induced by oxLDL. PCA decreased oxLDL-induced ROS overproduction and in particular prevented the early increase of ROS. This decrease seemed to be the main signal responsible for maintaining the intracellular redox homeostasis hindering the activation of p53 induced by ROS, p38MAPK, and PKCδ. Consequently the overexpression of the proapoptotic p53-target genes such as p66Shc protein did not occur. Finally, we demonstrated that PCA induced the activation of JNK, which, in turn, determined the increase of nuclear Nrf2, leading to inhibition of the early ROS overproduction. We concluded that the antiapoptotic mechanism of PCA was most likely related to the activation of the JNK-mediated survival signals that strengthen the cellular antioxidant defences rather than to the PCA antioxidant power.

Clinical evolution of celiac disease in Italy 1982-2002.

Goals: The aim of this work is to assess how the clinical features of celiac disease have changed in Italy after the widespread introduction of serologic tests in 1993. Study: Twenty Italian Clinical Centers collected information from 1982 until 2002 on 1968 patients older than 18 years diagnosed with celiac disease. Results: The results show that the incidence of atypical and silent cases of celiac disease has increased after the wider availability of serological test, which has allowed earlier diagnosis and treatment. Conclusions: This paper provides a view on the evolution of the clinical features of celiac disease in Italy over 2 decades. The relevance of the analysis is supported by the fact that Italy is one of the countries with the highest incidence of celiac disease. These findings underline the importance of a timely diagnosis of celiac disease.

Anti-inflammatory activity of extra virgin olive oil polyphenols: Which role in the prevention and treatment of immune-mediated inflammatory diseases?

BACKGROUND AND OBJECTIVE Altered inflammatory response characterizes chronic immunemediated inflammatory diseases (IMID) such as rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, systemic lupus erythematosus, and psoriasis. Accumulating evidence indicates that regular consumption of extra virgin olive oil (EVOO), the main source of fat in the Mediterranean diet, is associated with a reduced risk of developing chronic degenerative disorders such as cardiovascular diseases, type 2 diabetes and cancer. The beneficial effects on health of EVOO have been attributed, besides to the monounsaturated fats content, to the presence of phenolic compounds that have antioxidant, anti-inflammatory and immunomodulatory properties. The purpose of this review is to provide an overview of the effects of EVOO polyphenols on IMID highlighting the potential mechanisms of action. METHODS Scientific papers were found by searching in PubMed up to May 2017 using the following key words: rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, systemic lupus erythematosus, and psoriasis also in combination with EVOO, phenolic compounds, oleuropein, oleocantal, hydroxytyrosol,tyrosol and oleochantal. RESULTS In vitro and in vivo studies indicate that EVOO and its polyphenols can improve diseases symptoms in IMID, by acting both at local and systemic levels and by modulating several molecular pathways. Nevertheless, there are not sufficient data to achieve specific nutritional guidelines. CONCLUSION Further research is needed to evaluate the real contribution of EVOO and its phenolic compounds in modulating the IMID-associated inflammatory perturbations, in order to develop appropriate nutritional recommendations.

Neuropsychological assessment in congenital hypothyroid children: importance of timing of replacement therapy

Abstract Introduction: Early diagnosis by neonatal thyroid screening is crucial for intellectual and neuropsychological outcome of children with congenital hypothyroidism (CH). Nevertheless, numerous reports have shown that some CH children, even if early treated, still have neuropsychological sequelae at a later age. In this study, we investigate whether the occurrence of a delayed onset of therapy, despite newborn screening, can be responsible for psychomotor abnormalities. Subject and methods: Intellectual and neuropsychological development was assessed in a group of 29 CH children diagnosed by screening in a defined Italian region, in 3 CH children detected on the basis of clinical symptoms and in 11 CH adults born before the screening program was introduced. Thyroid assessment and clinical examination were also performed in these patients. Results: The screened CH children with delayed therapy onset (range:40–70 days) had mostly ectopic and eutopic thyroids and showed significantly lower mean intelligence quotients (90.8 ± 16 vs 106.2 ± 13) and lower mean scores on neuropsychological tests than earlier treated CH children (range: 7–30 days). Discussion: Our study points out that children with ectopic thyroid and dyshormonogenesis, although showing a milder thyroid deficit at screening, may be at risk for delayed onset of therapy and consequent cognitive damage prompt, and adequate treatment should be given in all types of primary CH to prevent mental disturbances in CH children.