The concept of barrier

In a previous article we analyzed the concept of barrier as an essential component to protect the organism against external environment.

The physiological barriers of our organism are:

• the epidermis
• the intestinal mucosa
• the genital mucosa
• the oral and nasal mucosa

These structures, formed by one or more layers of cells side by side as if they were bricks held together by the mortar, represent the first line of defense against harmful or pathogenic environmental agents. The defense function at the points of interface with the external environment is so important that most of the immune cells of the whole organism reside in the mucous membranes.

All barriers consist of:

• a cellular component (mono or multilayered)
• a bacterial component
• an immunological component

The spatial organization and biochemical interaction of these elements ensures correct separation from the external environment and, therefore, protection from it.

Skin and gut health are linked

Although the skin and intestinal mucosa are made up of different cells (keratinocytes and enterocytes, respectively), in reality they have many similarities regarding physiological aspects. In fact, both must hinder the passage of pathogens, environmental toxicants and chemical-physical agents such as UV rays, in the case of the skin, or prevent the passage of food contaminants, metals, bacteria, without prejudice to the exchange of water and nutrients, in the case of the intestine.

These functions are guaranteed by two fundamental aspects:

• the cohesion of the epithelial layer
• the balance of the commensal microbial population

As an example we can cite leaky gut syndrome, which we often hear about. This term refers to a condition of increased permeability of the epithelium (or a “detachment” of some parts of the membrane of the enterocytes, closely connected to each other, the so-called “tight junctions”) and consequently the passage of substances occurs harmful and bacteria through the epithelium with activation of a defensive response, which is inflammation in the intestine. The inflammatory process due to permeability does not resolve itself, as long as this problem remains, and this determines the consequent loss of balance in the commensal microbial populations, which can no longer carry out their balanced activities and lose their protective capacity. The perpetuation of this state of imbalance can establish an immune hyper-reactivity which, together with inflammation, can have repercussions on a systemic level.

Given that the causes of impaired permeability due to loss of “adhesion” in the epithelial tissue and consequent inflammation are common to all barriers, often the intestine is associated with a similar situation also for the epidermis. That is, dermatological problems (acne, rosacea, dermatitis, eczema, psoriasis) coexist with intestinal problems. Sometimes, moreover, respiratory problems such as asthma, rhinitis or bronchitis can be found in association.

Dysbiosis and the altered permeability of the epithelial layer go hand in hand: while in physiological conditions there is a synergy of protection, in pathological conditions the alteration of one affects the functioning of the other. The common denominator is the inflammatory process that fuels the functional deterioration of the barrier.

The good news is that if purposefully action is taken on the cellular component, it is possible to restore the functioning of the barriers. In the case of the intestine, the integrity of the enterocyte layer and the arrest of the inflammatory process are two priorities, and targeted and synergistic interventions both to balance the microbiota and to abolish the inflammatory state can lead to the true solution of the disorders.

Lipidomics in intestinal and dermatological problems: not just omega-3s!

The lipidomic study of the mature red blood cell membrane in persons who report intestinal and dermatological problems often disclose one or more of the following characteristics:

• excess of arachidonic acid (omega-6): as we have previously commented, the inflammation represented by this fatty acid is the common denominator of the functional alterations of the barriers;
• alteration of normal levels of EPA and/or DHA (omega-3): these fatty acids are precursors of lipid mediators of inflammatory resolution. If they are deficient, the inflammation persists and can become a chronic state, both local and systemic.

It must also be underline that, with the habit of “do it yourself” for the choice of the supplement, we are observing more and more cases of excess omega-3 in the membranes, such as result of excessive or unnecessary doses. The excess of omega-3 alters the structure of the membrane, unsettle the anchor points of the cell-cell junctions and consequently the permeability of cell membranes. At the same time, omega-3 fatty acids, being easily peroxidable molecules, increase the reactivity of the tissue to oxidative stress, perpetuating the inflammatory and immunological stress of the barrier. In the case of the skin, this factor plays a crucial role due to direct contact with atmospheric agents with an oxidizing action.

• Eicosatrienoic acid deficiency (DGLA, omega-6): this omega-6 fatty acid can perform an anti-inflammatory control function, acting in the balance between the omega-3 and omega-6 components in cell membranes. In fact, it plays a central role especially in dermatological problems in which a poor functioning of the delta-6 desaturase enzyme is known, with a consequent decrease in the level of DGLA.
• excess of saturated fats: an inflammatory condition, is also favored by the increase in the level of saturated fatty acids which increase the production of inflammatory cytokines.

As evident, the intervention scheme in case of intestinal and dermatological problems is not unique, but depends on the lipidomic profile of the cell membranes, performed on the mature red blood cell, and on which imbalance has been observed in the subject: therefore the approach is personalized and the supplementation intervention is “precision”.

---

Article by the editorial team of Lipinutragen

The information provided must in no way replace the direct relationship between health professional and patient.
The food recommendations in the article are not intended as a substitute for a personalized meal plan and are to be adapted to specific cases.

---

Photo: 123RF Archivio Fotografico: 60689750 : ©lculig

Download

Essential nutrients against “empty” calories

Nutrition is a determining factor for human health. Paradoxically, although the guidelines for healthy eating are known, are continually disregarded particularly in Western countries.

Likewise, in the rest of the world, with the growth of the Gross Domestic Product (GDP), we are witnessing a westernization of the diet with the simultaneous dietetic impoverishment of nutrients in the midst of many, too many “empty” calories. This transition is occurring in these decades in countries with emerging economies such as China, India, etc. (Figure 1).

The graph shows the growing trend of empty calories – in the study published in the journal Nature (1) – including refined sugars, along with refined alcohol and fats.

Nowadays sugars are present everywhere, even in unthinkable products such as: bread in a box, crackers, yogurt, vegetables in a jar, breakfast cereals, ketchup, sauces, etc.

The fact that this ingredient increases food palatability makes it an advantage for the industry that sees sales increase and a disadvantage for the health of the individual who is led to eat over the due.

It is no coincidence that we are talking about a real epidemic of obesity, of diabetes and of cardiometabolic diseases.

Some alarming data on sugar consumption

An American adult consumes an average of 73 grams of sugar per day **.
An American teenager consumes an average of 82 grams of sugar a day **.

The World Health Organization recommends reducing the intake of sugar to less than 5% of calories (about 25 g in adults). This recommendation is strongly opposed and at the moment the official limit has remained at 10% of the total daily calories.

An installation recently placed in Times Square in New York, depicts the figure of a nine-year-old child made of sugar, to highlight that on average, at that age, the equivalent of their weight in sugar is consumed in a year.

Beware of sweet drinks: in the US, around 21% of the total calories consumed by the population comes from sugary drinks!

Addiction to junk food rich in sugar and industrial fats

The one for sugar is a real dependency for the human being established during the evolution enhanced by the sense of pleasure generated by its consumption. The food resources research has led man to a strong attraction for the sweet taste (read this), for salty and for fatty foods. Unfortunately, this instinct is also known to the industrial world that uses it to increase the attractiveness and therefore the consumption of its food products, negatively impacting public health.

During the XII symposium 2017 “Hungry for Change: Food Insecurity, Stress and Obesity” in Los Angeles, it was highlighted that junk foods rich in sugar and industrial fats occupy 50% of the commercial surface of the stores; are placed on the shelves more accessible and have very low prices, thanks to the low cost of raw materials and state aid. Knowing that the areas of the brain called “pleasure centers” are also activated by visual stimuli through dopamine, it is easy to understand how the pervasive presence of junk food in the wards of supermarkets leads consumers to the compulsive purchase of such products.

7 tips for a sugar free life

1. Try an experiment that consists of staying a month following a diet without added sugars. Start with snacks, because they are those in which the sugar determines more the glycemic peaks with the inevitable subsequent hypoglycemia and consequently responsible for fatigue and hunger attacks.
2. Check the products in your pantry and place all those containing sugar in a garage box (make sure the box is large). Sugary drinks are the first to be eliminated. Review even the least suspicious products, such as yogurts, fruit juices, boxed bread, etc.
3. Learn to recognize the sugar even in disguise: sucrose, fructose, dextrose, syrup, sucralose, etc ….
4. Pay attention to products called “light” and with 0 fats. In almost all cases fat reduction has been replaced by a greater presence of sugars, proving far from an advantage for the reduction of body fat.
5. Do not add sugar to tea, coffee, etc. Get used to the taste of food gradually. Start by replacing it with honey.
6. Replace all types of products indicated with real foods, such as dried fruit, fresh fruit or dried fruit. Start to rediscover traditional recipes, decreasing the amount of sugar proposed, especially in the presence of ingredients based on fruit. Even the bio and natural kitchen can be a good source of preparations with the use of whole meal flour and with reduced amounts of sweeteners such as honey.
7. Maintain a good state of hydration. Water, tea, herbal teas, coffee without sugar. Sometimes tiredness comes from poor hydration.

Be encouraged by what the world of research tells us; a recent study (2) conducted on more than 600 individuals, found that dietary regimens lacking added sugars, refined cereals and industrial food products, led to significant weight loss, without worrying about calorie counting. Can be more effective over time to adopt food changes that become a real lifestyle more than using slimming diets for limited periods of time!

---

• Read more about the consumption of sugar read this
• For a sugar free recipe, we recommend the article: https://www.lipinutragen.it/en/attraction-for-sweet-flavor-and-sugar-free-recipe

---

 

Bibliography

(1) David Tilman, Michael Clark. Global diets link environmental sustainability and human health. Nature. 2014, volume 515, pages 518–522.
(2) Christopher D. Gardner, John F. Trepanowski, Liana C. Del Gobbo, et al. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion. The DIETFITS Randomized Clinical Trial. JAMA. 2018;319(7):667-679.

---

Article by:
Nutritionist Dr. Francesco Bonucci

The diet tips, written in the article, are not intended to be a substitute for a personal nutrition plan and are to be adapted to specific cases.

---

Photo: 123RF Archivio Fotografico | ©photka, 37166797, 2018-04-09 | ©Oleksandra Naumenko, 56078845, 2018-04-09

 

Download

INTESTINE: the interface between the external and internal environment of the organism

In the jargon the intestine is identified with its excretory activity, but it is ignored that this organ is home to multiple functions, some of which produce effects on organs and systems external to the gastro-enteric tract. Its coating epithelium is the mucosa with the largest surface of the human body and represents the interface of passage from the external to the internal environment of the organism.

The main functions of this physical, biochemical and immunological barrier are those of:

• absorption of digested nutrients (amino acids, sugars, triglycerides, water, etc.);
• defence against toxins, pathogens, antigens of different nature or other peptides with immunogenic action.

The intestine cannot be considered separated from its mucus layer and from the microbiota that has formed since the intrauterine life (with its bacteriocins, cytokines and immunoglobulins), but should be considered as a single functional unit (Fig. 1).

The link between the intestinal lining and the discovery of zonulin

The English term of leaky gut means an altered intestinal permeability (2).

Although there are numerous studies on leaky gut, this condition has not yet fully emerged from the field of research; its presence in the onset of food intolerances and extra intestinal autoimmune pathologies is well established and continues to grow (3).

Until the mid-seventies, the cells of the intestinal epithelium were thought to be “glued” together seamlessly and only the mechanism of passage of substances through the enterocytes (transcellular absorption) existed.

The discovery of zonulin was fundamental for the understanding of intestinal permeability.

Starting from studies on cholera and then, after those, on celiac disease, the Italian doctor Alessio Fasano discovered the existence of a protein called zonulin (4) that combines the intestinal epithelium in tight junctions, leaving 15 Angstrom space. This discovery made possible the development of knowledge on the mechanisms that regulate the paracellular passages, revealing that it is a dynamic system that can open or close this communication path based on certain stimuli.

What causes leaky gut?

The main causes of an alteration of the function of the intestinal barrier, accompanied by the activation of zonulin, are:

• microbial imbalance or maladaptation (dysbiosis);
• use of non-steroidal anti-inflammatory drugs (NSAIDs);
• chemo and radiotherapy;

• alcohol;
• stress;
• systemic inflammation;
• infections.

The triad Genetics – Environment – Microbiota assumes the key role in the pathogenesis of diseases related to abnormal intestinal permeability and, the last two, are the elements on which prevention can be performed.

Genetics, once considered the most important determinant of our destiny, has been significantly reduced after the discovery that our code is made up of only 23,000 genes, compared to about 120,000 expected.

The “diet” element to nourish the components of intestinal microflora

It is clear that the most important environmental factor on which to act is the diet that, besides nourishing ourselves and being a key to epigenetic modulation, supplies food for the colonies of microorganisms inhabit our intestine. For the same reason, industrial foods, rich in additives, colourings, preservatives, etc.*, become almost indigestible and not suitable for supplying the healthy components of our intestinal microflora. We must remember that the rapid food changes occurred in the last decades, have distorted human nutrition, unbalancing and impoverishing it with nutritional values ​​and fibers; this has also led to changes in the type of commensal microbiota, reducing wealth in species and changing relationships.

*The main additives to watch out for and whose presence is growing exponentially in a wide variety of foods, including baked goods, preserved meats and dairy products are: sugars, salt, emulsifiers (e.g. mono- and diglycerides), organic solvents, nano particles, microbial transglutaminase, enzymes (5).

The presence of a leaky gut allows the access of an antigen from the intestinal lumen to the immune system present in the lamina of the intestine with consequent activation of the lymphoid tissue and the production of a cascade of immune reactions.

Which pathologies are associated with leaky gut syndrome?

The main pathologies for which the scientific literature confirms the association of intestinal permeability syndrome are:

• Celiac disease
• Diabetes mellitus type 1
• Asthma
• Multiple sclerosis
• Chronic intestinal inflammatory diseases

• Ankylosing spondylitis
• Obesity
• Non-alcoholic steatosis hepatitis (NAFLD)
• Psoriasis

 

How to intervene in case of impaired intestinal permeability:

It is advisable to monitor food allergies and intolerances, including non-celiac gluten sensitivity followed by an appropriate diet.

For those who are celiac, it is advisable to periodically check their diet and the presence of cross-contamination.

Reduction or occasional consumption of alcohol. Use of NSAIDs only as needed or in accordance with updated treatment plans.

Exclude the packaged products and all foods containing the additives mentioned.

Introduce the daily practice of specific techniques aimed at reducing stress. (e.g. mindfulness – cardiac consistency, yoga, Qi-gong).

There are specific supplements that have regulatory action on the intestinal epithelium such as glutamine, zinc, probiotics and Saccharomyces boulardii, as well as some drugs still in clinical trials, which would act directly on the “tight junction“.

---

Bibliography:

(1) Mu Q, Kirby J, Reilly CM, Luo XM. Leaky Gut As a Danger Signal for Autoimmune Diseases. Front Immunol. 2017 May 23;8:598. https://www.frontiersin.org/articles/10.3389/fimmu.2017.00598/full
(2) Green P, Jones R. Celiac Disease: A Hidden Epidemic. New York, NY: Harper Collins; 2006:98.
(3) Barbara G. et al., Mucosal permeability and immune activation as potential therapeutic targets of probiotics in irritable bowel syndrome. J Clin Gastroenterol. 2012 Oct;46 Suppl:S52-5.
(4) Fasano A. Intestinal permeability and its regulation by zonulin: diagnostic and therapeutic implications. Clin Gastoenterol H. 2012;10(10):1096-1100.
(5) Lerner A, Matthias T. Changes in intestinal tight junction permeability associated with industrial food additives explain the rising incidence of autoimmune disease. Autoimmun Rev. 2015;14(6):479-489.

---

Article by:
Nutritionist Dr. Francesco Bonucci

The diet tips, written in the article, are not intended to be a substitute for a personal nutrition plan and are to be adapted to specific cases.

---

Photo: 123RF Archivio Fotografico | ©Irina Strelnikova, 86189593, 2018-02-10 | ©Wang Chun-Kuan, 69812970, 2018-02-10 | ©guniita, 67016194, 2018-02-10 | Fig. 1: © 2017 Mu, Kirby, Reilly and Luo. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

 Download