Chiara Di Lorenzo

Molecular aspects of milk allergens and their role in clinical events.

AbstractMilk allergy is the most frequent food allergy in childhood. Even though cases of newly developed milk allergy in adulthood are known, this allergy is less frequent in adults since it is normally outgrown by children during the first years of life. One of the reasons why allergy to cow’s milk shows its highest prevalence in children is its early introduction into the diets of babies when breast feeding is not possible. The major allergens are caseins and β-lactoglobulin, but allergies to other minor proteins (immunoglobulins, bovine serum albumin) have also been reported. Milk allergenicity can be reduced by various treatments (mainly hydrolysis), meaning that formulas based on cow’s milk can often be safely fed to children allergic to milk proteins. Cross-reactivity has been described between different mammalian milks and between milk and meat or animal dander. Cross-contamination can result from inadequate cleaning of industrial equipment and constitutes a hidden danger for allergic subjects who unknowingly ingest milk proteins. FigureInvolvement (expressed as percentage of total subjects) of the most abundant milk proteins in the sensitization of 80 children allergic to cow’s milk. The upper panel includes all positive responses, even minor ones; data in the lower panel are restricted to the most severe positive responses (see text for details). SPT, skin prick test; CAP, CAP test; IMM, immunoblotting; alpha-LA, α-lactalbumin; beta-LG, β-lactoglobulin; cas, caseins; BSA, bovine serum albumin

Plant Food Supplements with Anti-Inflammatory Properties: A Systematic Review (II)

The aim of this systematic review is to summarize the evidence for or against the efficacy of plant food supplements (PFS) for coping inflammatory conditions by considering epidemiological and human intervention studies. The review considers six botanical species commonly used as food supplements/medicinals: Urtica dioica L., Symphytum officinalis L., Calendula officinalis L., Curcuma longa L., Boswellia serrata Roxb., and Harpagophytum procumbens L. The search retrieved 579 publications. By removing the duplicates and applying the inclusion/exclusion criteria, the final number of papers was 47. No epidemiological data were found. The bibliographic search found no paper regarding the anti-inflammatory effects of Calendula officinalis L. and Symphytum officinalis L. by oral use. In spite of the long-term traditional use for inflammatory disorders, Curcuma longa L. and Harpagophytum procumbens L. warrant further investigation, whereas the efficacy of Urtica dioica L, even if the available data on hard endpoints are promising, requires other trials. Boswellia serrata Roxb. was found to be the most promising, since it shows the best efficacy for the treatment of pain/inflammatory conditions. In conclusion, it is advisable to conduct further studies with more homogeneous population and larger number of subjects by avoiding the heterogeneity of the herbal preparations considered.

Bioavailability of wine-derived phenolic compounds in humans: a review

Phenolic compounds are produced in the seeds and skins of grapes, and are transferred into wine during the fermentation process. Phenolic compounds can also be imparted into wine from maturation and storage in oak wood barrels after fermentation. The consumption of wine, an alcoholic beverage, has been observed in epidemiological studies to reduce the risk of cardiovascular disease and certain cancers, as well as diabetes and dementia, in a J-shaped relationship between amount consumed and level of risk. The bioactivity of wine primarily observed in vitro and ex vivo, may result from wines relatively high content of phenolic compounds, which is similar to that observed in fruits and vegetables; a Mediterranean fruit and vegetable rich-diet is also associated with a reduced risk of cardiovascular disease and cancers. If the wine-derived phenolic compounds or their active metabolites are not absorbed in sufficient amounts and in a readily available form for cells, however, then they are less likely to have any significant in vivo activity. This review considers and discusses the available data to date on the bioavailability of the different wine-derived phenolic compounds in humans.

Biochemical and immunochemical characterization of different varieties of amaranth (Amaranthus L. ssp.) as a safe ingredient for gluten-free products.

Celiac disease is a food intolerance triggered by the ingestion of gluten-containing cereals; the only therapy is a strict gluten-free diet for life. In recent years, amaranth flour has received considerable attention as an interesting source for the formulation of gluten-free products due to its high nutritional value and low content of prolamins, the toxic proteins for celiacs. The aim of this study was to characterize 40 amaranth varieties using both SDS-PAGE/immunoblotting and ELISA to assess their possible tolerance by celiac subjects. All of the amaranth samples studied showed similar binding affinities for both specific anti-gliadin antibodies and human IgAs. In most amaranth grains, the content of gluten-like proteins measured by ELISA was <20 ppm. The molecular characterization of amaranth proteins suggests that amaranth is safe for celiacs to consume. It is recommended that the most suitable amaranth varieties are those having the lowest content of proteins cross-reacting with anti-gliadin antibodies.

Metabolic Syndrome and Inflammation: A Critical Review of In Vitro and Clinical Approaches for Benefit Assessment of Plant Food Supplements

Metabolic syndrome is defined as the clustering in an individual of several metabolic abnormalities associated with insulin resistance, type 2 diabetes, and obesity, in which low-grade chronic inflammatory activity is commonly observed. Part of the European Project PlantLIBRA is concerned with methods to assess the benefits of plant food supplements (PFSs) in countering inflammatory activity and metabolic syndrome. This paper summarizes the current methods used for benefit assessment of PFS, taking into consideration only in vitro, in silico, and clinical methodologies used to investigate the anti-inflammatory properties of plants. No in silico studies (using computer simulation) related to metabolic syndrome were found; these methods appear to be used exclusively for identifying or testing potentially effective compounds in drug development. Most in vitro methods for the assessment of beneficial effects of botanicals or plant food supplements in diabetes were based on a quantitative polymerase chain reaction (PCR), whereas the preferred kind of clinical study was the double-blind randomized controlled clinical trial. Only two parameters were observed to change after treatment with botanicals in both in vitro and in vivo studies: interleukin-6 and tumour necrosis factor-α, and these biomarkers should be carefully considered in future studies for PFS benefit assessment.

Could 1,3 dimethylamylamine (DMAA) in food supplements have a natural origin?

1,3 dimethylamylamine or methylexaneamine (DMAA) is a synthetic pharmaceutical patented in the 1940s as a nasal decongestant which can be used as a recreational stimulant. Alleged to occur in nature, DMAA has become a widely used ingredient in sports food supplements, despite its status as a doping agent and concerns over its safety. There is now some doubt as to whether it can be sourced naturally or whether it actually occurs naturally at all. The presence of DMAA was investigated by high performance liquid chromatography (HPLC) in extracts of the leaves and stems of four geranium species and of three well-known cultivars. The amounts of DMAA in commercial geranium (Pelargonium graveolens) oil and the leading sports supplement which uses the ingredient were also measured. DMAA was not found in any of the leaves or stems or in the commercial geranium oil included in this study. Approximately 30 mg per daily dose was found in the food supplement. Therefore, the amount of DMAA found in the supplement is most unlikely to have been sourced in nature, and it must be concluded that synthetic DMAA, known to be capable of causing severe adverse physiological effects, has been added.

Biochemical and immunochemical evidences supporting the inclusion of quinoa (Chenopodium quinoa Willd.) as a gluten-free ingredient.

To date, the only acceptable therapeutic approach for celiac disease (CD) is a strict elimination from the diet of gluten-containing foods, but this diet does not always guarantee an adequate nutritional intake. Pseudocereals are receiving considerable attention as interesting alternatives for the formulation of gluten-free products, and quinoa grains arise as nutritive substitutes of conventional cereals. The aim of this study was the characterization of different quinoa samples corresponding to 11 quinoa varieties, using polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) and immunoblotting techniques to assess their suitability for celiac subjects. Some of these varieties were grown in Italy to assess if the reproduction in a new habitat can guarantee the retention of the “safe” protein pattern. None of the quinoa varieties studied presented protein bands with electrophoretic mobility comparable with those of wheat gliadins, the toxic protein for celiac subjects. All the quinoa samples showed a low binding affinity for both specific anti-gliadin antibodies and IgAs from celiac subjects, confirming that quinoa can be considered as a safe ingredient for celiac patients. However, reliable varieties should be previously selected since the immuno cross-reactivity with anti-gliadin antibodies can vary significantly.

Adverse Effects of Plant Food Supplements and Plants Consumed as Food: results from the Poisons Centres-Based PlantLIBRA Study

Plant food supplements (PFS) are products of increasing popularity and wide‐spread distribution. Nevertheless, information about their risks is limited. To fill this gap, a poisons centres‐based study was performed as part of the EU project PlantLIBRA. Multicentre retrospective review of data from selected European and Brazilian poisons centres, involving human cases of adverse effects due to plants consumed as food or as ingredients of food supplements recorded between 2006 and 2010. Ten poisons centres provided a total of 75 cases. In 57 cases (76%) a PFS was involved; in 18 (24%) a plant was ingested as food. The 10 most frequently reported plants were Valeriana officinalis, Camellia sinensis, Paullinia cupana, Melissa officinalis, Passiflora incarnata, Mentha piperita, Glycyrrhiza glabra, Ilex paraguariensis, Panax ginseng, and Citrus aurantium. The most frequently observed clinical effects were neurotoxicity and gastro‐intestinal symptoms. Most cases showed a benign clinical course; however, five cases were severe. PFS‐related adverse effects seem to be relatively infrequent issues for poisons centres. Most cases showed mild symptoms. Nevertheless, the occurrence of some severe adverse effects and the increasing popularity of PFS require continuous active surveillance, and further research is warranted. Copyright

Allergenic Proteins in Enology: A Review on Technological Applications and Safety Aspects

Proteinaceous products are widely used as fining agents during winemaking to remove unwanted insoluble particles and undissolved microscopic particles (colloidal material) from the must or wine to improve stability. Some of them (egg white, caseinates, and fish gelatine) have allergenic potential and the presence of their residues in the final product could represent a risk for allergic individuals. Moreover, lysozyme (an egg allergen) is included among wine additives to control the fermentation processes and avoid spoiling during winemaking. The aim of this paper is to review the experimental/clinical data on the use of allergenic products in enology and the measurement of relative risk for sensitized subjects. In addition, methods developed specifically for the quantification of allergenic residues in must and wine are described.

Immunochemical investigation of allergenic residues in experimental and commercially-available wines fined with egg white proteins.

Proteinaceous egg whites are widely used as a fining agent during the production of red wines. Residues of egg white in the final wine could present a risk for individuals allergic to eggs. This study investigated the presence of allergenic residues in both red and white wines fined with egg whites. Experimental and commercially available wines fined with egg whites, with or without subsequent bentonite fining, were studied. Unfined wines were used as negative controls. The physicochemical characteristics of each wine were determined to assess their possible role in enhancing or hindering the elimination of allergenic residues from wine. The amount of egg white protein residues was investigated both by a specifically developed/validated ELISA test and by immunoblotting. Both immunochemical tests used the same anti-total egg white protein antibody and were highly sensitive to the allergen. No egg white protein was detected in the wines studied in either immunochemical test, irrespective of the physicochemical characteristics of the wine, the type and dosage of the fining agent and the oenological process used. The risk of adverse reactions in egg-allergic individuals should therefore be considered negligible, but the exemption from labelling should be allowed only when the absence of residues is confirmed by analytical controls.