Microbiota-Derived Extracellular Vesicles as a Postbiotic Strategy to Alleviate Diarrhea and Enhance Immunity in Rotavirus-Infected Neonatal Rats

Rotavirus (RV) infection is a major cause of acute gastroenteritis in children under 5 years old, resulting in elevated mortality rates in low-income countries. The efficacy of anti-RV vaccines is limited in underdeveloped countries, emphasizing the need for novel strategies to boost immunity and alleviate RV-induced diarrhea. This study explores the effectiveness of interventions involving extracellular vesicles (EVs) from probiotic and commensal E. coli in mitigating diarrhea and enhancing immunity in a preclinical model of RV infection in suckling rats. On days 8 and 16 of life, variables related to humoral and cellular immunity and intestinal function/architecture were assessed. Both interventions enhanced humoral (serum immunoglobulins) and cellular (splenic natural killer (NK), cytotoxic T (Tc) and positive T-cell receptor γδ (TCRγδ) cells) immunity against viral infections and downregulated the intestinal serotonin receptor-3 (HTR3). However, certain effects were strain-specific. EcoR12 EVs activated intestinal CD68, TLR2 and IL-12 expression, whereas EcN EVs improved intestinal maturation, barrier properties (goblet cell numbers/mucin 2 expression) and absorptive function (villus length). In conclusion, interventions involving probiotic/microbiota EVs may serve as a safe postbiotic strategy to improve clinical symptoms and immune responses during RV infection in the neonatal period. Furthermore, they could be used as adjuvants to enhance the immunogenicity and efficacy of anti-RV vaccines.

Development and characterization of a poloxamer hydrogel composed of human mesenchymal stromal cells (hMSCs) for reepithelization of skin injuries

Wound healing is a natural physiological reaction to tissue injury. Hydrogels show attractive advantages in wound healing not only due to their biodegradability, biocompatibility and permeability but also because provide an excellent environment for cell migration and proliferation. The main objective of the present study was the design and characterization of a hydrogel loaded with human mesenchymal stromal cells (hMSCs) for use in would healing of superficial skin injures. Poloxamer 407® was used as biocompatible biomaterial to embed hMSCs. The developed hydrogel containing 20 % (w/w) of polymer resulted in the best formulation with respect to physical, mechanical, morphological and biological properties. Its high swelling capacity confirmed the hydrogel's capacity to absorb wounds' exudate. LIVE/DEAD® assay confirm that hMSCs remained viable for at least 48 h when loaded into the hydrogels. Adding increasing concentrations of hMSCs-loaded hydrogel to the epithelium did not affect keratinocytes' viability and healing capacity and all wound area was closed in less than one day. Our study opens opportunities to exploit poloxamer hydrogels as cell carriers for the treatment of skin superficial wound.

Microbiota-Derived Extracellular Vesicles Promote Immunity and Intestinal Maturation in Suckling Rats

Microbiota-host communication is primarily achieved by secreted factors that can penetrate the mucosal surface, such as extracellular membrane vesicles (EVs). The EVs released by the gut microbiota have been extensively studied in cellular and experimental models of human diseases. However, little is known about their in vivo effects in early life, specifically regarding immune and intestinal maturation. This study aimed to investigate the effects of daily administration of EVs from probiotic and commensal E. coli strains in healthy suckling rats during the first 16 days of life. On days 8 and 16, we assessed various intestinal and systemic variables in relation to animal growth, humoral and cellular immunity, epithelial barrier maturation, and intestinal architecture. On day 16, animals given probiotic/microbiota EVs exhibited higher levels of plasma IgG, IgA, and IgM and a greater proportion of Tc, NK, and NKT cells in the spleen. In the small intestine, EVs increased the villi area and modulated the expression of genes related to immune function, inflammation, and intestinal permeability, shifting towards an anti-inflammatory and barrier protective profile from day 8. In conclusion, interventions involving probiotic/microbiota EVs may represent a safe postbiotic strategy to stimulate immunity and intestinal maturation in early life.

Efficacy of Apremilast Gels in Mouse Model of Imiquimod-Induced Psoriasis Skin Inflammation

Apremilast (APM) is a novel drug for the treatment of psoriasis and psoriatic arthritis. APM is a phosphodiesterase 4 (PDE4) inhibitor, raising intracellular cAMP levels and thereby decreasing the inflammatory response by modulating the expression of TNF-α, IL-17, IL-23, and other inflammatory cytokines. The goal of this study is to develop APM gels as a new pharmaceutical formulation for the treatment of topical psoriasis. APM was solubilized in Transcutol-P and incorporated into Pluronic F127, Sepigel, and carbomer bases at different proportions. All formulations were characterized physiochemically. A biopharmaceutical study (release profile) was performed, and ex vivo permeation was evaluated using a human skin model. A toxicity assay was carried out on the HaCaT cell line. A mouse model of imiquimod-induced psoriasis skin inflammation was carried out to determine its efficacy by histological analysis, RNA extraction, and RT-qPCR assays. APM gel formulations showed good physicochemical characteristics and a sustained release profile. There was no permeation of any gel measured through human skin, indicating a high retained amount of APM on the skin. Cell viability was greater than 80% at most dilution concentrations. APM gels treated the psoriasis mouse model, and it shows a reduction in the proinflammatory cytokines (IL-8, IL-17A, IL-17F, and IL-23). APM gels could be a new approach for the treatment of topical psoriasis.

Semi-Solid Dosage Forms Containing Pranoprofen-Loaded NLC as Topical Therapy for Local Inflammation: In Vitro, Ex Vivo and In Vivo Evaluation

Pranoprofen (PRA)-loaded nanostructured lipid carriers (NLC) have been dispersed into blank gels composed of 1% of Carbomer 940 (PRA-NLC-Car) and 3% of Sepigel^® 305 (PRA-NLC-Sep) as a novel strategy to refine the biopharmaceutical profile of PRA, for dermal administration in the treatment of skin inflammation that may be caused by possible skin abrasion. This stratagem intends to improve the joining of PRA with the skin, improving its retention and anti-inflammatory effect. Gels were evaluated for various parameters such as pH, morphology, rheology, and swelling. In vitro drug release research and ex vivo permeation through the skin were carried out on Franz diffusion cells. Additionally, in vivo assays were carried out to evaluate the anti-inflammatory effect, and tolerance studies were performed in humans by evaluating the biomechanical properties. Results showed a rheological profile common of semi-solid pharmaceutical forms for dermal application, with sustained release up to 24 h. In vivo studies using PRA-NLC-Car and PRA-NLC-Sep in Mus musculus mice and hairless rats histologically demonstrated their efficacy in an inflammatory animal model study. No signs of skin irritation or modifications of the skin's biophysical properties were identified and the gels were well tolerated. The results obtained from this investigation concluded that the developed semi-solid formulations represent a fitting drug delivery carrier for PRA's transdermal delivery, enhancing its dermal retention and suggesting that they can be utilized as an interesting and effective topical treatment for local skin inflammation caused by a possible abrasion.

Effect of Rotavirus Infection and 2'-Fucosyllactose Administration on Rat Intestinal Gene Expression

Viral infections are described as modifying host gene expression; however, there is limited insight regarding rotavirus (RV) infections. This study aimed to assess the changes in intestinal gene expression after RV infection in a preclinical model, and the effect of 2-fucosyllactose (2'-FL) on this process. From days 2 to 8 of life, rats were supplemented with the dietary oligosaccharide 2'-FL or vehicle. In addition, an RV was inoculated on day 5 to nonsupplemented animals (RV group) and to 2'-FL-fed animals (RV+2'-FL group). Incidence and severity of diarrhea were established. A portion from the middle part of the small intestine was excised for gene expression analysis by microarray kit and qPCR. In nonsupplemented animals, RV-induced diarrhea upregulated host antiviral genes (e.g., Oas1a, Irf7, Ifi44, Isg15) and downregulated several genes involved in absorptive processes and intestinal maturation (e.g., Onecut2, and Ccl19). The 2'-FL-supplemented and infected animals had less diarrhea; however, their gene expression was affected in a similar way as the control-infected animals, with the exception of some immunity/maturation markers that were differentially expressed (e.g., Ccl12 and Afp). Overall, assessing the expression of these key genes may be useful in the evaluation of the efficacy of nutritional interventions or treatments for RV infection.

Caspofungin-Loaded Formulations for Treating Ocular Infections Caused by Candida spp

Fungal keratitis causes corneal blindness worldwide. The treatment includes antibiotics, with Natamycin being the most commonly used; however, fungal keratitis is difficult to treat, so alternative therapies are needed. In situ gelling formulations are a promising alternative; this type of formulation has the advantages of eye drops combined with the advantages of ointments. This study was designed to develop and characterize three formulations containing 0.5% CSP: CSP-O1, CSP-O2, and CSP-O3. CSP is an antifungal drug that acts against a diverse variety of fungi, and Poloxamer 407 (P407) is a polymer of synthetic origin that is able to produce biocompatible, biodegradable, highly permeable gels and is known to be thermoreversible. Short-term stability showed that formulations are best stored at 4 °C, and rheological analysis showed that the only formulation able to gel in situ was CSP-O3. In vitro release studies indicated that CSP-O1 releases CSP most rapidly, while in vitro permeation studies showed that CSP-O3 permeated the most. The ocular tolerance study showed that none of the formulations caused eye irritation. However, CSP-O1 decreased the cornea's transparency. Histological results indicate that the formulations are suitable for use, with the exception of CSP-O3, which induced slight structural changes in the scleral structure. All formulations were shown to have antifungal activity. In view of the results obtained, these formulations could be promising candidates for use in the treatment of fungal keratitis.

Galectins-1, -3 and -9 Are Present in Breast Milk and Have a Role in Early Life Development

Galectins (Gal) are a family of conserved soluble proteins with high affinity for β-galactoside structures. They have been recognized as important proteins for successful pregnancy. However, little is known about their presence in breast milk and their role in early infancy. Gal-1, -3 and -9 concentrations were evaluated by Multiplex immunoassays in mother–infant pairs from the MAMI cohort in maternal plasma (MP) (n = 15) and umbilical cord plasma (UCP) (n = 15) at birth and in breast milk samples (n = 23) at days 7 and 15 postpartum. Data regarding mother and infant characteristics were collected. Gal-9 was present in a lower concentration range than Gal-1 and Gal-3 in plasma, specifically in UCP. A major finding in the current study is that Gal-1, -3 and -9 were detected for the first time in all the transitional breast milk samples and no differences were found when comparing the two breastfeeding time points. Finally, Gal levels were associated with some maternal and infant characteristics, such as gestational age, pregnancy weight gain, maternal diet, the gender, infant growth and infant infections. In conclusion, Gal levels seem to be involved in certain developmental aspects of early life.

Staphylococcus epidermidis' Overload During Suckling Impacts the Immune Development in Rats

Mastitis is an inflammation of the mammary gland occurring in 3-33% of the breastfeeding mothers. The majority of mastitis cases have an infectious etiology. More than 75% of infectious mastitis are caused by Staphylococcus epidermidis and Staphylococcus aureus and involves breast milk microbiota alteration, which, may have an impact in lactating infant. The aim of this study was to analyze in rats during the suckling period and later in life the impact of a high and a low overload of Staphylococcus epidermidis, similarly as it occurs during the clinical and the subclinical mastitis, respectively. From days 2 to 21 of life, suckling rats were daily supplemented with low (Ls group) or high (Hs group) dose of S. epidermidis. Body weight and fecal humidity were periodically recorded. On days 21 and 42 of life, morphometry, hematological variables, intestinal gene expression, immunoglobulin (Ig) and cytokine profile and spleen cells' phenotype were measured. Although no differences were found in body weight, Ls and Hs groups showed higher body length and lower fecal humidity. Both doses induced small changes in lymphocytes subpopulations, reduced the plasma levels of Ig and delayed the Th1/Th2 balance causing a bias toward the Th2 response. No changes were found in cytokine concentration. The low dose affected the Tc cells intestinal homing pattern whereas the high dose had an impact on the hematological variables causing leukocytosis and lymphocytosis and also influenced the intestinal barrier maturation. In conclusion, both interventions with Staphylococcus epidermidis overload during suckling, affects the immune system development in short and long term.

Effect of Penetration Enhancers and Safety on the Transdermal Delivery of Apremilast in Skin

The poor water solubility of apremilast (APR) is the main impediment to the penetration of the drug through the skin barrier. The objective of this study was to evaluate the permeability of APR in different solutions enriched with penetration promoters in ex vivo samples of human skin, and additionally assess its tolerance in vivo. To this end, APR solutions with 5% promoter were developed, and the drug's ability to penetrate human abdominal skin samples was evaluated; the coefficients of permeability, cumulated amounts permeated, and flow were some of the parameters evaluated; likewise, the in vitro and in vivo tolerance of the solutions was evaluated. The results obtained showed that the solutions containing squalene as a promoter improved the penetration of APR compared to the other promoters evaluated; in the same way, on an in vitro scale in HaCaT cells, the promoters were not toxic, finding a cell viability greater than 80% at the different dilutions evaluated. In the in vivo tests carried out with the solution that presented the best results (APR-Squalene solution), it was observed that it does not cause irritation or erythema on the skin after its colorimetric and histological evaluation of the dorsal region of rats after its application. Squalene becomes an excellent candidate to improve the permeability of the drug in the case of the development of a topical formulation; in addition, it was confirmed that this penetration enhancer is neither toxic nor irritating when in contact with the skin in in vivo tests.

Preventive Effect of a Postbiotic and Prebiotic Mixture in a Rat Model of Early Life Rotavirus Induced-Diarrhea

Rotavirus (RV) is the main cause of gastroenteritis in children. Prebiotics and, more recently, postbiotics are used for preventing and treating gastrointestinal infections. The aim of this study was to analyze the effects of a Lactofidus^TM, short-chain galacto-oligosaccharides (scGOS) and long-chain fructo-oligosaccharides (lcFOS) mixture, and their combination on RV infection, in a rat model, for early life diarrhea. Fifteen litters of suckling rats were intragastrically administered daily with the vehicle, the prebiotic mixture, the postbiotic or the combination. The RV was inoculated on day 5 and then fecal samples were clinically evaluated daily. Viral shedding, intestinal permeability assay, in vitro blocking assay, immunoglobulin profiles, and anti-RV response were assessed at day 8 and 16 of life. Cecal microbiota composition, intestinal gene expression, and short chain fatty acids (SCFAs) were analyzed at day 16. The incidence and severity of diarrhea were significantly reduced by all the supplementations. Moreover, they showed blocking activity, changes in the immunoglobulin profiles, in gut microbiota, and in the intestinal gene expression. The prebiotic mixture reduced gut permeability and changed the SCFA profile, whereas the postbiotic enhanced the expression of Toll-like receptors (TLRs). The combination preserved most of the individual observed effects, and furthermore, complementary effects, such as an increase in white blood cells and lymphocytes recruitment, as well as upregulation of TLR7 and TLR9 gene expression.

New Formulations Loading Caspofungin for Topical Therapy of Vulvovaginal Candidiasis

Vulvovaginal candidiasis (VVC) poses a significant problem worldwide affecting women from all strata of society. It is manifested as changes in vaginal discharge, irritation, itching and stinging sensation. Although most patients respond to topical treatment, there is still a need for increase the therapeutic arsenal due to resistances to anti-infective agents. The present study was designed to develop and characterize three hydrogels of chitosan (CTS), Poloxamer 407 (P407) and a combination of both containing 2% caspofungin (CSP) for the vaginal treatment of VVC. CTS was used by its mucoadhesive properties and P407 was used to exploit potential advantages related to increasing drug concentration in order to provide a local effect. The formulations were physically, mechanically and morphologically characterized. Drug release profile and ex vivo vaginal permeation studies were performed. Antifungal efficacy against different strains of Candida spp. was also evaluated. In addition, tolerance of formulations was studied by histological analysis. Results confirmed that CSP hydrogels could be proposed as promising candidates for the treatment of VVC.

Effects of a Postbiotic and Prebiotic Mixture on Suckling Rats' Microbiota and Immunity

Human milk serves as a model for infant formula providing nutritional solutions for infants not able to receive enough mother’s milk. Infant formulas aim to mimic the composition and functionality of human milk by providing ingredients reflecting those of the latest human milk insights, such as prebiotics, probiotics and postbiotics. The aim of this study was to examine the effects of the supplementation with a postbiotic (Lactofidus^TM) and its combination with the prebiotics short-chain galactooligosaccharides (scGOS) and long-chain fructooligosaccharides (lcFOS) in a preclinical model of healthy suckling rats. Pups were supplemented daily with Lactofidus^TM (POST group) and/or scGOS/lcFOS (P+P and PRE groups, respectively). Body weight and fecal consistency were analyzed. At the end of the study, immunoglobulin (Ig) profile, intestinal gene expression, microbiota composition and short chain fatty acid (SCFA) proportion were quantified. The supplementation with all nutritional interventions modulated the Ig profile, but the prebiotic mixture and the postbiotic induced differential effects: whereas scGOS/lcFOS induced softer feces and modulated microbiota composition and SCFA profile, Lactofidus™ upregulated Toll-like receptors gene expression. The use of the combination of scGOS/lcFOS and Lactofidus™ showed the effects observed for the oligosaccharides separately, as well as showing a synergistic impact on animal growth. Thus, the combined use of both products seems to be a good strategy to modulate immune and microbial features in early life.

Screening Anti-Inflammatory Effects of Flavanones Solutions

There are a large number of remedies in traditional medicine focused on relieving pain and inflammation. Flavanones have been a potential source in the search for leading compounds and biologically active components, and they have been the focus of much research and development in recent years. Eysenhardtia platycarpa is used in traditional medicine for the treatment of kidney diseases, bladder infections, and diabetes mellitus. Many compounds have been isolated from this plant, such as flavones, flavanones, phenolic compounds, triterpenoid acids, chalcones, sugars, and fatty acids, among others. In this paper, natural flavanone 1 (extracted from Eysenhardtia platycarpa) as lead compound and flavanones 1a–1d as its structural analogues were screened for anti-inflammatory activity using Molinspiration^® and PASS Online in a computational study. The hydro alcoholic solutions (FS) of flavanones 1, 1a–1d (FS1, FS1a–FS1d) were also assayed to investigate their in vivo anti-inflammatory cutaneous effect using two experimental models, a rat ear edema induced by arachidonic acid (AA) and a mouse ear edema induced by 12-O-tetradecanoylphorbol acetate (TPA). Histological studies and analysis of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were also assessed in AA-inflamed rat ear tissue. The results showed that the flavanone hydro alcoholic solutions (FS) caused edema inhibition in both evaluated models. This study suggests that the evaluated flavanones will be effective when used in the future in skin pathologies with inflammation, with the results showing 1b and 1d to be the best.

The Breast Milk Immunoglobulinome

Breast milk components contribute to the infant’s immune development and protection, and among other immune factors, immunoglobulins (Igs) are the most studied. The presence of IgA in milk has been known for a long time; however, less information is available about the presence of other Igs such as IgM, IgG, and their subtypes (IgG1, IgG2, IgG3, and IgG4) or even IgE or IgD. The total Ig concentration and profile will change during the course of lactation; however, there is a great variability among studies due to several variables that limit establishing a clear pattern. In this context, the aim of this review was firstly to shed light on the Ig concentration in breast milk based on scientific evidence and secondly to study the main factors contributing to such variability. A search strategy provided only 75 studies with the prespecified eligibility criteria. The concentrations and proportions found have been established based on the intrinsic factors of the study—such as the sampling time and quantification technique—as well as participant-dependent factors, such as lifestyle and environment. All these factors contribute to the variability of the immunoglobulinome described in the literature and should be carefully addressed for further well-designed studies and data interpretation.

Rat Milk and Plasma Immunological Profile throughout Lactation

The composition of bioactive factors with immune activity in human breast milk is widely studied. However, the knowledge on rat milk immune factors during the whole lactation period is still scarce. This study aimed to analyze rat breast milk’s immunoglobulin (Ig) content and some critical adipokines and growth factors throughout the lactation period, and to assess relationships with corresponding plasma levels. During lactation, milk concentration of the transforming growth factor (TGF)-β2 and -β3 showed a punctual increase in the first week, whereas adiponectin and leptin remained stable. In the second period of lactation (d14–21), despite the increase in the milk epidermal growth factor (EGF), a decrease in fibroblast growth factor 21 (FGF21) was detected at day 21. Milk IgA concentration had a progressive increase during lactation, while no significant changes were found in IgM and IgG. Regarding plasma levels, a decrease in all studied adipokines was observed in the second period of lactation, with the exception of IgA and TGF-β1, which reached their highest values at the end of the study. A positive correlation in IgM, IgG, and adipokine concentration was detected between milk and plasma compartments. In summary, the changes in the pattern of these bioactive compounds in rat milk and plasma and their relationships during lactation are established.

Association of Maternal Microbiota and Diet in Cord Blood Cytokine and Immunoglobulin Profiles

Mothers confer natural passive immunization to their infants through the transplacental pathway during the gestation period. The objective of the present study was to establish at birth the maternal and cord plasma concentration and relationship of immunoglobulins (Igs), cytokines (CKs), and adipokines. In addition, the impact of the maternal microbiota and diet was explored. The plasma profile of these components was different between mothers and babies, with the levels of many CKs, IgM, IgG2a, IgE, IgA, and leptin significantly higher in mothers than in the cord sample. Moreover, the total Igs, all IgG subtypes, IgE, and the Th1/Th2 ratio positively correlated in the mother–infant pair. Maternal dietary components such as monounsaturated fatty acids-polyunsaturated fatty acids and fiber were positively associated with some immune factors such as IgA in cord samples. The microbiota composition clustering also influenced the plasma profile of some factors (i.e., many CKs, some Ig, and adiponectin). In conclusion, we have established the concentration of these immunomodulatory factors in the maternal–neonatal pair at birth, some positive associations, and the influence of maternal diet and the microbiota composition, suggesting that the immune status during pregnancy, in terms of CKs and Igs levels, can influence the immune status of the infant at birth.

Endogenous Antioxidant Cocktail Loaded Hydrogel for Topical Wound Healing of Burns

The main goal of this work is the study of the skin wound healing efficacy of an antioxidant cocktail consisting of vitamins A, D, E and the endogenous pineal hormone melatonin (MLT), with all of these loaded into a thermosensitive hydrogel delivery system. The resulting formulation was characterized by scanning electron microscopy. The antioxidant efficacy and microbiological activity against Gram positive and Gram negative strains were also assayed. The skin healing efficacy was tested using an in vivo model which included histological evaluation. Furthermore, atomic force microscopy was employed to evaluate the wound healing efficacy of rat skin burns through the determination of its elasticity at the nanoscale using force spectroscopy analysis. The resulting hydrogel exhibited sol state at low temperature and turned into a gel at 30 ± 0.2 °C. The hydrogel containing the antioxidant cocktail showed higher scavenging activity than the hydrogel containing vitamins or MLT, separately. The formulation showed optimal antimicrobial activity. It was comparable to a commercial reference. It was also evidenced that the hydrogel containing the antioxidant cocktail exhibited the strongest healing process in the skin burns of rats, similar to the assayed commercial reference containing silver sulfadiazine. Histological studies confirmed the observed results. Finally, atomic force microscopy demonstrated a similar distribution of Young's modulus values between burned skin treated with the commercial reference and burned skin treated with hydrogel containing the antioxidant cocktail, and all these with healthy skin. The use of an antioxidant cocktail of vitamins and MLT might be a promising treatment for skin wounds for future clinical studies.

Apremilast Microemulsion as Topical Therapy for Local Inflammation: Design, Characterization and Efficacy Evaluation

Apremilast (APR) is a selective phosphodiesterase 4 inhibitor administered orally in the treatment of moderate-to-severe plaque psoriasis and active psoriatic arthritis. The low solubility and permeability of this drug hinder its dermal administration. The purpose of this study was to design and characterize an apremilast-loaded microemulsion (APR-ME) as topical therapy for local skin inflammation. Its composition was determined using pseudo-ternary diagrams. Physical, chemical and biopharmaceutical characterization were performed. Stability of this formulation was studied for 90 days. Tolerability of APR-ME was evaluated in healthy volunteers while its anti-inflammatory potential was studied using in vitro and in vivo models. A homogeneous formulation with Newtonian behavior and droplets of nanometric size and spherical shape was obtained. APR-ME released the incorporated drug following a first-order kinetic and facilitated drug retention into the skin, ensuring a local effect. Anti-inflammatory potential was observed for its ability to decrease the production of IL-6 and IL-8 in the in vitro model. This effect was confirmed in the in vivo model histologically by reduction in infiltration of inflammatory cells and immunologically by decrease of inflammatory cytokines IL-8, IL-17A and TNFα. Consequently, these results suggest that this formulation could be used as an attractive topical treatment for skin inflammation.

Melatonin nanogel promotes skin healing response in burn wounds of rats

Aim: Development of a melatonin nanogel intended for wound healing (WH) application. Materials & methods: The main components of the nanogel were poloxamer 407, chitosan and hyaluronic acid. The nanogel was characterized by the assessment of physical interactions, swelling, wettability, rheological properties and internal structure. The drug release, antimicrobial efficacy against different strains and biocompatibility with human keratinocytes were also tested. Finally, the WH efficacy was evaluated in rats. Results: The nanogel showed optimal physicochemical properties and an internal network of interconnected channels from which melatonin was released following first order kinetics. Antimicrobial activity was similar to commercial reference material and it promoted epidermis growth with evident wound contraction. Conclusion: Melatonin nanogel can be proposed as a promising system for WH.

Modulation of the Systemic Immune Response in Suckling Rats by Breast Milk TGF-β2, EGF and FGF21 Supplementation

Breast milk is a rich fluid containing bioactive compounds such as specific growth factors (GF) that contribute to maturation of the immune system in early life. The aim of this study was to determine whether transforming growth factor-β2 (TGF-β2), epidermal growth factor (EGF) and fibroblast growth factor 21 (FGF21), compounds present in breast milk, could promote systemic immune maturation. For this purpose, newborn Wistar rats were daily supplemented with these GF by oral gavage during the suckling period (21 days of life). At day 14 and 21 of life, plasma for immunoglobulin (Ig) quantification was obtained and spleen lymphocytes were isolated, immunophenotyped and cultured to evaluate their ability to proliferate and release cytokines. The main result was obtained at day 14, when supplementation with EGF increased B cell proportion to reach levels observed at day 21. At the end of the suckling period, all GF increased the plasma levels of IgG1 and IgG2a isotypes, FGF21 balanced the Th1/Th2 cytokine response and both EGF and FGF21 modified splenic lymphocyte composition. These results suggested that the studied milk bioactive factors, mainly EGF and FGF21, may have modulatory roles in the systemic immune responses in early life, although their physiological roles remain to be established.

Strain-Specific Probiotic Properties of Bifidobacteria and Lactobacilli for the Prevention of Diarrhea Caused by Rotavirus in a Preclinical Model

Probiotic supplementation with different lactobacilli and bifidobacterial strains has demonstrated beneficial effects in infectious diarrhea caused by rotavirus (RV) in young children. Preclinical models of RV infection might be a good strategy to screen for the efficacy of new probiotic strains or to test their comparative efficacy. Neonatal Lewis rats were supplemented with Bifidobacterium breve M-16V, Lactobacillus acidophilus NCFM, Lactobacillus helveticus R0052, or Lactobacillus salivarius PS2 from days 2–14 of life. On day five, animals received RV SA-11 orally. Fecal samples were collected daily, weighed, and scored for the calculation of severity and incidence of diarrhea. In addition, fecal pH and fecal viral shedding were measured. Animals were sacrificed at the end of the study and their blood was obtained for the quantification of RV-specific immunoglobulins. RV infection was induced in ~90% of the animals. All probiotics caused a reduction of several clinical variables of severity and incidence of diarrhea, except L. salivarius PS2. L. acidophilus NCFM, B. breve M-16V, and L. helveticus R0052 seemed to be very effective probiotic strains. In addition, all Lactobacillus strains reduced the viral elimination one day post-inoculation. No differences were detected in the specific anti-RV humoral response. The present study highlights the strain-specific effects of probiotics and identifies promising probiotics for use in ameliorating and preventing RV-induced diarrhea in children, for example by including them in infant formulas.

Leptin and EGF Supplementation Enhance the Immune System Maturation in Preterm Suckling Rats

In preterm newborns the immaturity of the immune system is remarkable, with reduced innate and adaptive immune responses. Many bioactive compounds in breast milk, such as growth factors and adipokines, contribute to the immune system’s maturation in early life. However, studies on the immunoregulatory activity in preterm neonates are practically nonexistent. The aim of the present study was to determine whether a nutritional supplementation in early life with leptin or epidermal growth factor (EGF) was able to promote the maturation of the systemic and intestinal immune system in preterm conditions. For this purpose, premature rats were daily supplemented by oral gavage with leptin or EGF. Term and Preterm groups receiving vehicle were used as controls. Preterm rats showed deficiencies compared to full-term ones, such as lower body weights, erythrocyte counts, plasma IgG and IgM concentrations and B cell percentages, and higher values of Th and Tc TCRαβ⁺ cells in mesenteric lymph nodes, and intestinal permeability, among others. However, leptin and EGF supplementation were able to revert some of these deficiencies and to improve the premature immune system’s development. These results suggest that leptin and EGF are involved in enhancing the maturation of the systemic and intestinal immune system in preterm conditions.

Design and evaluation of a multifunctional thermosensitive poloxamer-chitosan-hyaluronic acid gel for the treatment of skin burns

The main goal of this study was the design, development and characterization of a poloxamer/chitosan/hyaluronic based vehicle including three biological antioxidant molecules such as vitamins A, D and E aimed at improving the treatment of skin burns. The physical characterization of hydrogel, its mechanical and rheological properties as well as internal structure were investigated. Furthermore, biological characteristics such as ex vivo antimicrobial properties and in vivo wound healing were also accomplished and compared with a commercial reference. Results showed optimal physicochemical properties with biocompatible pH value of 4.6 ± 0.1 and zeta potential dependent on pH. The swelling rate was around 350% with optimal wettability, adhesion and leakage properties, as well as thermosensitive gelation processes. The microbiological assay demonstrated similar antimicrobial activity to that of commercial reference. In vivo tolerance study revealed no skin reactions. Finally, the wound healing efficacy of hydrogel in skin burn model showed dermal appendages and similar epidermis, dermis and stratum corneum to the commercial reference. These findings indicated that our hydrogel loading vitamins could be considered an outstanding candidate for further clinical studies.

A Preterm Rat Model for Immunonutritional Studies

Neonates are born with an immature immune system, which develops during the first stages of life. This early immaturity is more acute in preterm newborns. The aim of the present study was to set up a preterm rat model, in which representative biomarkers of innate and adaptive immunity maturation that could be promoted by certain dietary interventions are established. Throughout the study, the body weight was registered. To evaluate the functionality of the intestinal epithelial barrier, in vivo permeability to dextrans was measured and a histomorphometric study was performed. Furthermore, the blood cell count, phagocytic activity of blood leukocytes and plasmatic immunoglobulins (Ig) were determined. Preterm rats showed lower erythrocyte and platelet concentration but a higher count of leukocytes than the term rats. Although there were no changes in the granulocytes’ ability to phagocytize, preterm monocytes had lower phagocytic activity. Moreover, lower plasma IgG and IgM concentrations were detected in preterm rats compared to full-term rats, without affecting IgA. Finally, the intestinal study revealed lower permeability in preterm rats and reduced goblet cell size. Here, we characterized a premature rat model, with differential immune system biomarkers, as a useful tool for immunonutritional studies aimed at boosting the development of the immune system.

Nanoemulsion strategy of pioglitazone for the treatment of skin inflammatory diseases

Pioglitazone (PGZ) is a peroxisome proliferator-activated receptor agonist. Its role in the inflammatory response modulation paves the way for additional therapeutic applications. The purpose of this study was to develop a pioglitazone nanoemulsion (PGZ-NE) in order to investigate its anti-inflammatory efficacy on the skin. To that end, an NE vehicle developed for skin delivery was optimized and characterized. The resulting PGZ-NE showed good anti-inflammatory efficacy by decreasing the expression of inflammatory cytokines IL-6, IL-1β and TNF-α. The properties of the developed nanocarrier allowed achievement of a high permeation flux of PGZ through the skin as well as a high retained amount in the skin, likely due to the depot effect of ingredients, which assured a prolonged local action, with good skin tolerability among participating individuals. Consequently, these results suggest that PGZ-NE may be used as an alternative treatment for inflammatory skin diseases such as rosacea, atopic dermatitis or psoriasis.

Skin-controlled release lipid nanosystems of pranoprofen for the treatment of local inflammation and pain

Aim: The design and development of pranoprofen (PF) nanostructured lipid carriers (NLCs) for topical treatment of local inflammation and pain. Materials & methods: PF-NLCs were designed and optimized by central rotatable composite design. A physicochemical characterization was addressed. Release and skin permeation were performed in Franz diffusion cells. In vivo anti-inflammatory efficacy was assayed in mice and tolerance study in humans. Results: PF-NLCs F7 and F10 provided sustained release, good stability and optimal skin retention avoiding systemic undesired side effects. Anti-inflammatory activity was enhanced, suggesting an improved efficacy as compared with standard formulation. No skin irritancy was detected. Conclusion: Topical PF-NLCs F7 and F10 could be effective and safe new therapeutic tools for the treatment of local inflammation and pain.

[Formula: see text]

A new food frequency questionnaire to assess chocolate and cocoa consumption

OBJECTIVE

Cocoa has been highlighted as a food with potential benefits to human health because of its polyphenol content. However, few studies show the contribution of cocoa and chocolate products in polyphenol intake. The aim of this work was to develop a food frequency questionnaire (FFQ) for evaluating the intake of food products containing cocoa (C-FFQ).

METHODS

A sample of 50 university students was recruited to complete the 90-item questionnaire, a validated questionnaire (called here European Food Safety Authority [EFSA]-Q) as well as a 24-hour dietary recall (24 HDR). Spearman correlation test, Bland-Altman plots, and quintile classification analysis were conducted together with the Wilcoxon test and descriptive statistics.

RESULTS

Significant correlations between the C-FFQ and the EFSA-Q for the most common cocoa/chocolate products were observed (P < 0.05), as well as between data from the C-FFQ and 24 HDR (P < 0.05). However, a number of cocoa/chocolate products frequently consumed by the participants were detected by the C-FFQ and 24 HDR which were not included in the EFSA-Q. According to the C-FFQ, chocolate bars were the main source of cocoa in university students, but dairy products also provided an important amount of cocoa.

CONCLUSION

The developed C-FFQ questionnaire can be considered as a valid option for assessing the consumption frequency of cocoa/chocolate-derived products, thereby allowing the evaluation of cocoa polyphenol intake in further studies.