Multiunit In Vitro Colon Model for the Evaluation of Prebiotic Potential of a Fiber Plus D-Limonene Food Supplement

The search for new fiber supplements that can claim to be “prebiotic” is expanding fast, as the role of prebiotics and intestinal microbiota in well-being has been well established. This work explored the prebiotic potential of a novel fiber plus D-Limonene supplement (FLS) in comparison to fructooligosaccharides (FOS) over distal colonic fermentation with the in vitro model MICODE (multi-unit in vitro colon gut model). During fermentation, volatilome characterization and core microbiota quantifications were performed, then correlations among volatiles and microbes were interpreted. The results indicated that FLS generated positive effects on the host gut model, determining: (i) eubiosis; (ii) increased abundance of beneficial bacteria, as Bifidobacteriaceae; (iii) production of beneficial compounds, as n-Decanoic acid; (iv) reduction in detrimental bacteria, as Enterobaceteriaceae; (v) reduction in detrimental compounds, as skatole. The approach that we followed permitted us to describe the prebiotic potential of FLS and its ability to steadily maintain the metabolism of colon microbiota over time. This aspect is two-faced and should be investigated further because if a fast microbial turnover and production of beneficial compounds is a hallmark of a prebiotic, the ability to reduce microbiota changes and to reduce imbalances in the productions of microbial metabolites could be an added value to FLS. In fact, it has been recently demonstrated that these aspects could serve as an adjuvant in metabolic disorders and cognitive decline

Molecules Present in Plant Essential Oils for Prevention and Treatment of Colorectal Cancer (CRC)

Essential oils (EOs) are a complex mixture of hydrophobic and volatile compounds synthesized from aromatic plants, commonly present in the human diet. In recent years, many in vitro studies have suggested possible anticancer properties of single EO compounds, on colorectal cancer (CRC) cells. However, the majority of these studies did not compare the effects of these compounds on normal and cancer colon cells. By using NCM-460, a normal human mucosal epithelial cell line, Caco-2, a human colon epithelial adenocarcinoma cell line, and SW-620, colon cancer cells derived from lymph node metastatic site, we identified cinnamaldehyde, derived from cinnamon EO and eugenol, derived from bud clove EO, as compounds with a specific anticancer action selectively targeting the transformed colonic cells. Both cinnamaldehyde (75 M) and eugenol (800 M), after 72 h of treatment, were capable to induce apoptosis, necrosis and a cell cycle slowdown in Caco-2 and in SW-620, but not in NCM-460 cells. If associated with a targeted delivery to the colon, these two compounds could prove effective in the prevention or treatment of CRC

RNAi-Based Strategies for Cyclooxygenase-2 Inhibition in Cancer

Cyclooxygenase-2 (COX-2) enzyme has been involved in the tumorigenesis and in the progression of colorectal cancer (CRC). The use of traditional nonsteroidal anti-inflammatory drugs (NSAIDs) or selective COX-2 inhibitors has been proposed for the prevention and the treatment of this relevant neoplastic disease. In the light of an innovative alternative to these pharmacological approaches, we review here the possible strategies to achieve a strong and selective inhibition of COX-2 enzyme by using the mechanism of RNA Interference (RNAi) targeted against its mRNA. Anti-COX-2 siRNA molecules (siCOX-2) can be generated in CRC cells from short hairpin RNA (shRNA) precursors, delivered in vitro by a retroviral expression system, and induce a significant and stable silencing of overexpressed COX-2 in human colon cancer cells. As a safer alternative to viral approach, nonpathogenic bacteria (E. coli) can be engineered to invade eukaryotic cells and to generate siCOX-2 molecules in cancer cells. Moreover, the involvement of miRNAs in COX-2 posttranscriptional regulation opens up the possibility to exploit an endogenous silencing mechanism to knockdown overexpressed COX-2. Thus, these recent strategies disclose new challenging perspectives for the development of clinically compatible siRNA or miRNA capable of selectively inhibiting COX-2 enzyme

Micronutrient Deficiencies and Nutritional Pattens as Possible Risk Factors in the Onset of Retinopathy in Type 2 Diabetic Patients

Diabetic retinopathy (DR) is a common complication in diabetes. Many studies have demonstrated a strong correlation between diet and the onset and progression of diabetes, but only few focused on possible link between nutritional patterns, micronutrient deficiency and DR. In this observational study, by using 10-day food diary recordings, we analyzed the eating habits of 34 patients affected by DR, 35 controls with a long history of type 2 diabetes mellitus (T2DM) but no retinopathy and 35 matched healthy subjects. Macro- and micronutrient intakes were calculated based on the Italian food composition database of the Center of Research for Food and Nutrition (CREA) by using a validated nutritional software. Moreover, the adherence to the Mediterranean diet (MD) was evaluated by using a widely adopted questionnaire. Respect to the type 2 diabetic group the average daily intake of vitamin A (total retinol activity equivalents) was strongly reduced in DR group (524 vs 1072 mg/d, P<0.01); those of vitamin C was also reduced in DR group (48.0 vs 85.2 mg/d, P<0.01) as well as vitamin D (3.73 vs 5.40 mg/d, P<0.01). Copper average daily intake was lower in DR group (0,50 vs 0,82 mg/d, P<0.01) and similarly potassium intake was lower in this group respect to the type 2 non retinopathic diabetic one (1271 vs 2180 mg/d, P<0.01). DR patients also showed a significatively lower adherence to the MD respect to the T2DM patients and to the healthy subjects. This study confirmed a possible role of unhealthy nutritional patterns and micronutrient deficiency in the development and progression of the diabetic retinopathy

Cellular Prion Protein and Caveolin-1 Interaction in a Neuronal Cell Line Precedes Fyn/Erk 1/2 Signal Transduction

It has been reported that cellular prion protein (PrPc) is enriched in caveolae or caveolae-like domains with caveolin-1 (Cav-1) participating to signal transduction events by Fyn kinase recruitment. By using the Glutathione-S-transferase (GST)-fusion proteins assay, we observed that PrPc strongly interacts in vitro with Cav-1. Thus, we ascertained the PrPc caveolar localization in a hypothalamic neuronal cell line (GN11), by confocal microscopy analysis, flotation on density gradient, and coimmunoprecipitation experiments. Following the anti-PrPc antibody-mediated stimulation of live GN11 cells, we observed that PrPc clustered on plasma membrane domains rich in Cav-1 in which Fyn kinase converged to be activated. After these events, a signaling cascade through p42/44 MAP kinase (Erk 1/2) was triggered, suggesting that following translocations from rafts to caveolae or caveolaelike domains PrPc could interact with Cav-1 and induce signal transduction events

Is the clinical pattern of pediatric celiac disease changing? A thirty-years real-life experience of an Italian center

Objectives Clinical presentation of pediatric celiac disease (CD) is heterogeneous and ever-evolving. Our aim is to highlight its changes throughout the years. Methods Data about clinical presentation of CD in children diagnosed between 1990 and 2020 at the CD Center of Maggiore Hospital, Bologna, were collected. Patients were stratified into groups based on the date [P1 (1990-2011), P2 (2012-2020)] and age [G1 (< 2 years), G2 (2-5), G3 (6-11), G4 (12-18)] at diagnosis, then investigated by comparing CD clinical presentation in different periods and ages. Results 1081 children were selected. Mean age at diagnosis increases from 5.9 to 6.6 years from P1 to P2. Gastrointestinal Symptoms (GIs) are predominant, with a decline of diarrhea (47%VS30%) and an increase of constipation (4%VS19%) (p < 0.001). Among Extraintestinal symptoms (EIs) a decrease of anemia (76%VS43%, p = 0,001) is observed. Failure to Thrive (FTT) is stable throughout the years (p = 0.03), while screenings show a trend of increment (19%VS23%). GIs' frequency decline from G1 to G4 (p = 0,001), with reduction of diarrhea (p < 0.001), and rise of recurrent abdominal pain (p = 0,02). EIs are more frequent at older ages, FTT in younger patients. Conclusions Changes in clinical presentation of CD have occurred in the last 30 years. We observe a reduction of severe and classic gastroenterologic symptoms and a rise of atypical ones, together with a growth of serological screenings and higher age at diagnosis. Awareness about CD clinical trends is crucial for a proper approach and early diagnosis

Natural Compounds in the Modulation of the Intestinal Microbiota: Implications in Human Physiology and Pathology

Clinical interest in the human gut microbiota has increased considerably, because of the increasing number of studies linking the human intestinal microbiota and microbiome to an ever increasing number of non-communicable diseases. Many attempts at modulating the gut microbiota have been made using probiotics and prebiotics. However, there are other avenues that are still little explored from a clinical point of view that appear promising to obtain modifications of the microbial ecology and biological activities connected to the microbiome. This chapter summarizes all in vitro, in vivo and clinical studies demonstrating the possibility to positively modulate the intestinal microbiota by using probiotics, foods (and prebiotics), essential oils, fungus and officinal plants. For the future, clinical studies investigating the ability to modify the intestinal microbiota especially by using foods, officinal and aromatic plants or their extracts are required. More knowledge in this field is likely to be of clinical benefit since modulation of the microbiome might support the therapy of most non-communicable diseases in the future

Dietary geraniol by oral or enema administration strongly reduces dysbiosis and systemic inflammation in dextran sulfate sodium-treated mice

(Trans)-3,7-Dimethyl-2,6-octadien-1-ol, commonly called geraniol (Ge-OH), is an acyclic monoterpene alcohol with well-known anti-inflammatory, antitumoral, and antimicrobial properties. It is widely used as a preservative in the food industry and as an antimicrobial agent in animal farming. The present study investigated the role of Ge-OH as an anti-inflammatory and anti-dysbiotic agent in the dextran sulfate sodium (DSS)-induced colitis mouse model. Ge-OH was orally administered to C57BL/6 mice at daily doses of 30 and 120 mg kg(-1) body weight, starting 6 days before DSS treatment and ending the day after DSS removal. Furthermore, Ge-OH 120 mg kg(-1) dose body weight was administered via enema during the acute phase of colitis to facilitate its on-site action. The results show that orally or enema-administered Ge-OH is a powerful antimicrobial agent able to prevent colitis-associated dysbiosis and decrease the inflammatory systemic profile of colitic mice. As a whole, Ge-OH strongly improved the clinical signs of colitis and significantly reduced cyclooxygenase-2 (COX-2) expression in colonocytes and in the gut wall. Ge-OH could be a powerful drug for the treatment of intestinal inflammation and dysbiosis

Nutritional Biomarkers for the Prediction of Response to Anti-TNF-α Therapy in Crohn's Disease: New Tools for New Approaches

Crohn’s disease (CD) is a chronic disorder of the digestive tract characterized by an uncontrolled immune-mediated inflammatory response in genetically predisposed individuals exposed to environmental risk factors. Although diet has been identified as one of the major environmental risk factors, the role of nutrients in the clinical management of CD patients has not yet been fully investigated. In this prospective observational study, fifty-four patients diagnosed with active Crohn’s disease and undergoing anti-TNF-α biological therapy were enrolled and subjected to nutrient intake analysis through a daily food diary. Their nutrient intake and blood values were analyzed before and after 6 months of biological therapy. After 6 months of anti-TNF-α, four patients dropped out of the study, leaving 29 patients in clinical remission and 21 still with active disease that remained the same. The aim of this study was to identify nutrients whose intake or blood values may be associated with patients’ responses to biological therapy. In the diet, patients remaining with active CD showed very similar nutrient dietary intake compared to patients achieving remission except for a trend for lower starting zinc intake, below the reference value. In the blood, instead, patients who did not respond to biological therapy showed significantly lower plasma values of iron and taurine before starting biological anti-TNF-α treatmen

Responses of peripheral blood mononucleated cells from non-celiac gluten sensitive patients to various cereal sources

Non-celiac gluten sensitivity (NCGS) is still an undefined syndrome whose triggering mechanisms remain unsettled. This study aimed to clarify how cultured peripheral blood mononucleated cells (PBMC) obtained from NCGS patients responded to contact with wheat proteins. Results demonstrated that wheat protein induced an overactivation of the proinflammatory chemokine CXCL10 in PBMC from NCGS patients, and that the overactivation level depends on the cereal source from which proteins are obtained. CXCL10 is able to decrease the transepithelial resistance of monolayers of normal colonocytes (NCM 460) by diminishing the mRNA expression of cadherin-1 (CDH1) and tight junction protein 2 (TJP2), two primary components of the tight junction strands. Thus, CXCL10 overactivation is one of the mechanisms triggered by wheat proteins in PBMC obtained from NCGS patients. This mechanism is activated to a greater extent by proteins from modern with respect to those extracted from ancient wheat genotypes