Study Protocol for a Prospective, Unicentric, Double-Blind, Randomized, and Placebo-Controlled Trial on the Efficacy of a Low-Histamine Diet and DAO Enzyme Supplementation in Patients with Histamine Intolerance.

Background/objectives: Histamine intolerance is primarily caused by a deficiency in the diamine oxidase (DAO) enzyme at the intestinal level. The reduced histamine degradation in the gut leads to its accumulation in plasma, thereby causing multiple clinical manifestations, such as urticaria, diarrhea, headache, dyspnea, or tachycardia, among others. The dietary management of this food intolerance consists of the follow-up of a low-histamine diet, often combined with DAO supplementation.

Influence of Seed Disinfection Treatments on the Germination Rate and Histamine-Degrading Activity of Legume Sprouts.

Edible legume sprouts have been proposed as a promising plant-based source of the enzyme diamine oxidase (DAO), which plays a key role in degrading histamine at an intestinal level and preventing the development of histamine intolerance symptoms. However, the temperature and humidity conditions required for seed germination can also favor the rapid growth of yeast and mold, potentially compromising sprout yield and quality. The aim of this study was to evaluate the influence of different seed disinfection treatments on both the germination rate and DAO enzymatic activity in sprouts of four species.

Pilot Study on the Prevalence of Diamine Oxidase Gene Variants in Patients with Symptoms of Histamine Intolerance.

A retrospective pilot study was carried out to investigate the prevalence of four variants of the diamine oxidase (DAO) encoding gene () in Caucasian adults with symptoms of histamine intolerance. In a cohort of 100 patients and 100 healthy individuals, DAO-encoding gene non-synonymous Single Nucleotide Variations (SNVs) were genotyped by multiplex single-nucleotide primer extension (SNPE) and capillary electrophoresis, and serum DAO activity was analyzed with a radio-extraction assay. The study found that 79% of individuals with symptoms of histamine intolerance harbored one or more of the four SNVs associated with reduced DAO activity.

Comparative Assessment of the Nutritional Profile of Meat Products and Their Plant-Based Analogues.

Vegetarian and vegan diets are increasingly being adopted in Spain, a trend mainly driven by ethical concerns for animal welfare and the environment. This has resulted in a growing market for plant-based substitutes of meat products. However, available data on the nutritional value of such meat analogues in Mediterranean countries are still limited.

The dietary treatment of histamine intolerance reduces the abundance of some histamine-secreting bacteria of the gut microbiota in histamine intolerant women. A pilot study.

Restrictive diets for the treatment of different gastrointestinal disorders are reported to change the composition of intestinal microbiota. Recently, it has been proposed that individuals with histamine intolerance suffer from intestinal dysbiosis, having an overabundance of histamine-secreting bacteria, but how it is still unknown this state is affected by the usual dietary treatment of histamine intolerance [i.e.

1-methylhistamine as a potential biomarker of food histamine intolerance. A pilot study.

Efforts are currently being directed to identify a non-invasive marker that can serve as a solid and clinically irrefutable diagnostic criterion for histamine intolerance associated with diamine oxidase (DAO) deficiency. Accordingly, the identification of biomarkers of histamine (HA) metabolism in urine is proposed as a possible new diagnostic strategy. It is hypothesized that individuals with histamine intolerance could have a different urinary profile of HA and its metabolites in comparison with the healthy population.

The Rate of Histamine Degradation by Diamine Oxidase Is Compromised by Other Biogenic Amines.

Nowadays, certain uncertainties related to the onset of histamine adverse effects remain unsolved and still require further research. Questions still to be resolved include the wide range of doses at which dietary histamine may trigger symptoms of intoxication (100-10,000 mg/kg) or the appearance of symptoms of histamine intolerance after the consumption of foods presumable without histamine. It seems feasible that other amines, by acting as competitive substrates, could interfere with histamine degradation by the intestinal enzyme diamine oxidase (DAO).

Intestinal Dysbiosis in Patients with Histamine Intolerance.

An underlying cause of histamine intolerance is diamine oxidase (DAO) deficiency, which leads to defective homeostasis and a higher systemic absorption of histamine. Impaired DAO activity may have a genetic, pharmacological or pathological origin. A recent proposal also suggests it can arise from an alteration in the gut microbiota, although only one study has explored this hypothesis to date.

Influence of the Type of Breastfeeding and Human Milk Polyamines on Infant Anthropometric Parameters.

Feeding choices in the early months of life are key determinants of growth during infancy. Polyamines participate in cell proliferation and differentiation, and it has also been suggested that polyamine metabolism plays a role in adipogenesis. As the main exogenous source of polyamines in the infant is human milk, the aim of this work was to study if the type of breastfeeding received and the polyamine intake from human milk has an influence on infant anthropometric parameters.

Differences in Polyamine Content between Human Milk and Infant Formulas.

Human milk is the gold standard for nutrition during the first months of life, but when breastfeeding is not possible, it may be replaced by infant formulas, either partially or totally. Polyamines, which play an important role in intestinal maturation and the development of the immune system, are found both in human milk and infant formulas, the first exogenous source of these compounds for the newborn. The aim of this study was to evaluate the occurrence and evolution of polyamines in human milk during the first semester of lactation and to compare the polyamine content with that of infant formulas.

Influence of Breastfeeding Factors on Polyamine Content in Human Milk.

The polyamine content of human breast milk, which is the first exogenous source of polyamines for the newborn, can be affected by several factors associated with the mother, the infant, or breastfeeding itself. The aim of this study was to evaluate the influence of different breastfeeding factors on the polyamines found in human milk. For this study, a cohort of 83 mothers was considered for up to 4 months, and a subgroup of 33 mothers were followed during the first six months of breastfeeding.

Occurrence of Polyamines in Foods and the Influence of Cooking Processes.

Dietary polyamines are involved in different aspects of human health and play an important role in the prevention of certain chronic conditions such as cardiovascular diseases and diabetes. Different polyamines can be found in all foods in variable amounts. Moreover, several culinary practices have been reported to modify the content and profile of these bioactive compounds in food although experimental data are still scarce and even contradictory.

Low-Histamine Diets: Is the Exclusion of Foods Justified by Their Histamine Content?

A low-histamine diet is currently the most advised strategy to prevent the symptomatology of histamine intolerance. Conceptually, these diets should be founded on the exclusion of histamine-containing foods, although a certain disparity is found within the list of excluded foods in accordance with the different low-histamine diets available in the literature. This study aimed to critically review low-histamine diets reported in the scientific literature, according to the histamine and other biogenic amine contents of the excluded foods.

Histamine Intolerance: The Current State of the Art.

Histamine intolerance, also referred to as enteral histaminosis or sensitivity to dietary histamine, is a disorder associated with an impaired ability to metabolize ingested histamine that was described at the beginning of the 21st century. Although interest in histamine intolerance has considerably grown in recent years, more scientific evidence is still required to help define, diagnose and clinically manage this condition. This article will provide an updated review on histamine intolerance, mainly focusing on its etiology and the existing diagnostic and treatment strategies.

In vitro determination of diamine oxidase activity in food matrices by an enzymatic assay coupled to UHPLC-FL.

Intestinal diamine oxidase (DAO) acts as a protective barrier against exogenous histamine. A deficit of DAO activity can lead to the appearance of histamine intolerance, a clinical condition that may be treated by a low-histamine diet and oral DAO supplementation to enhance intestinal histamine degradation. As sources of DAO, porcine kidneys and certain legume seedlings are suitable components for the formulation of a DAO supplement.

Polyamines in Food.

The polyamines spermine, spermidine, and putrescine are involved in various biological processes, notably in cell proliferation and differentiation, and also have antioxidant properties. Dietary polyamines have important implications in human health, mainly in the intestinal maturation and in the differentiation and development of immune system. The antioxidant and anti-inflammatory effect of polyamine can also play an important role in the prevention of chronic diseases such as cardiovascular diseases.

Biogenic Amines in Plant-Origin Foods: Are They Frequently Underestimated in Low-Histamine Diets?

Low-histamine diets are currently used to reduce symptoms of histamine intolerance, a disorder in histamine homeostasis that increases plasma levels, mainly due to reduced diamine-oxidase (DAO) activity. These diets exclude foods, many of them of plant origin, which patients associate with the onset of the symptomatology. This study aimed to review the existing data on histamine and other biogenic amine contents in nonfermented plant-origin foods, as well as on their origin and evolution during the storage or culinary process.

New approach for the diagnosis of histamine intolerance based on the determination of histamine and methylhistamine in urine.

Histamine intolerance is a disorder in the homeostasis of histamine due to a reduced intestinal degradation of this amine, mainly caused by diamine oxidase (DAO) enzyme deficiency, which provokes its accumulation in plasma and the appearance of adverse health affects. A new approach for the diagnosis of this intolerance could be the determination of histamine and its metabolites in urine. The aim of this work was to develop and validate a rapid method to determine histamine and methylhistamine in human urine by Ultra High Performance Liquid Chromatography and Fluorimetric detection (UHPLC-FL).

Biologically active amines in fermented and non-fermented commercial soybean products from the Spanish market.

Biologically active amines were determined in commercial soybean products. The antioxidant polyamines were found in both non-fermented and fermented soybean products. Natto and tempeh showed the highest content of polyamines (75-124 and 11-24 mg/kg of spermidine and spermine, respectively).

The intracellular metabolism of isoflavones in endothelial cells.

Data from epidemiological and human intervention studies have highlighted potential cardiovascular benefits of soy isoflavone-containing foods. In humans, genistein and daidzein are extensively metabolized after absorption into glucuronides and sulfate metabolites. However, limited data exist on isoflavone cellular metabolism, in particular in endothelial cells.

Influence of ultra-high-pressure homogenization treatment on the phytosterols, tocopherols, and polyamines of almond beverage.

Ultra-high-pressure homogenization (UHPH) is an emerging technology based on the dynamic application of high pressure to obtain safe and high-quality liquid foods. The effect of six UHPH treatments at 200 and 300 MPa with different inlet temperatures (T(in)) (55, 65, and 75 °C) on the content of tocopherols, polyamines, and phytosterols of almond beverage was studied in comparison with the base product. Total tocopherol contents decreased about 80-90% as temperature and pressure increased, and whereas both parameters affected the tocopherol content, especially the effect of temperature was noticeable.

Isoflavone profile and protein quality during storage of sterilised soymilk treated by ultra high pressure homogenisation.

The application of ultra high pressure homogenisation (UHPH) treatments is useful to obtain fine and stable soymilk emulsions. Changes of isoflavones, protein digestibility and lysine availability during 4 months of storage at 20 ± 2°C in soymilk treated by UHPH (300 MPa and 75°C of inlet temperature) were studied in comparison to UHT-sterilised soymilk (142°C, 6s). Results indicated that although there was a significantly higher extractability of isoflavones in UHT (about 38%) than in UHPH-treated samples (about 15%), similar total contents were found at the end of storage.

Ultra-high-pressure homogenization (UHPH) system for producing high-quality vegetable-based beverages: physicochemical, microbiological, nutritional and toxicological characteristics.

Background: A relatively new technology based on a continuous system of ultra-high-pressure homogenization (UHPH) was used for producing high-quality soy and almond beverages as an alternative to conventional heat treatments (pasteurization and UHT). The aim of this study was to compare those treatments by analyzing the most relevant quality parameters with a broad vision from the production to the potential toxicological changes, passing through the main nutritional characteristics.

Results: UHPH treatment at 200 MPa, 55 °C T(in) produced a higher reduction of microorganisms than pasteurization.

Changes of isoflavones and protein quality in soymilk pasteurised by ultra-high-pressure homogenisation throughout storage.

Ultra high pressure homogenisation (UHPH) is an emerging technology to obtain fine and stable soymilk emulsions. Very little information is available about the stability of this kind of product during storage. Changes of isoflavone profile, protein digestibility and lysine availability in pasteurised-UHPH soymilks were studied for 21 days at 4 °C in comparison to heat-pasteurised soymilks.

Effect of ultra high pressure homogenization treatment on the bioactive compounds of soya milk.

Ultra high pressure homogenization (UHPH) is a useful novel technology to obtain safe and high-quality liquid foods. The effect of UHPH at 200 and 300 MPa in combination with different inlet temperatures (Tin) (55, 65 and 75 °C) on the bioactive compounds of soya milk was studied. Total phytosterols increased with the higher combination of pressure and temperature.