The science behind wet wipes for infant skin: Ingredient review, safety, and efficacy.

In the diapered area, the continuous exposure to excess moisture and irritants from urine and feces weakens the stratum corneum, making the skin more susceptible to irritation. The use of wet wipes for infants (baby wipes) is a common practice to clean skin after urine or a bowel movement, and this practice even extends to cleaning the hands and face, resulting in repeated daily use. Therefore, ensuring that baby wipes contain ingredients that are safe and mild on skin is important to help minimize skin irritation and discomfort. While disposable baby wipes have been shown to be effective and gentle at cleaning infant skin, even the skin of premature infants, there is growing public concern regarding their safety and tolerability. Not all products are made the same, as differences exist in manufacturing processes, ingredients, materials, safety, and quality testing. Therefore, it is important that healthcare professionals have accessible evidenced-based information on the safety and tolerability of common ingredients found in baby wipes to optimally educate their patients and families. Herein, we provide a review on best practices for ingredient selection, safety, and efficacy of baby wipes.

Neonatal Opioid Withdrawal Syndrome: A Developmental Care Approach.

Tens of thousands of infants are impacted yearly by prenatal opioid exposure. The term neonatal opioid withdrawal syndrome (NOWS) is now replacing the more familiar term neonatal abstinence syndrome (NAS). Ongoing debate continues related to standard regimens for treatment of this oftentimes perplexing condition. Historically, treatment has focused on pharmacologic interventions. However, there is limited research that points to nonpharmacologic methods of treatment as viable options, whether alone or in addition to pharmacologic interventions. This article, utilizing a review of pertinent literature, outlines the physical aspects of NOWS, including its pathophysiology and the resulting physical clinical signs. In addition, we present an overview of how age-appropriate, nonpharmacologic interventions, centered on developmental care, may be a valuable approach to organize and prioritize routine care for these infants, their families, and the health care team facing the challenges of NOWS. Finally, the need for further research to better define evidence-based standards of care for these infants and their families is discussed.

Benefits of Using an Appropriately Formulated Wipe to Clean Diapered Skin of Preterm Infants.

The skin of premature infants is underdeveloped rendering it more prone to break down and irritation. Therefore, special care is needed to protect premature skin and ensure it is not adversely affected. Many health care professionals advise using just water and cloth to clean diapered skin after a bowel movement despite evidence that shows improved infant skin health with the use of modern appropriately formulated baby wipes. This article describes the unique physiology of premature infant skin, reviews clinical evidence comparing use of baby wipes to water and cloth, and describes attributes of appropriately formulated baby wipes.

Comparative study of vulva and abdominal skin microbiota of healthy females with high and average BMI.

BACKGROUND: Obesity is known to modulate human health in a number of ways including altering the microbiome of the gut. Very few studies have examined the how obesity may affect the microbiomes of sites distant to the gut. We hypothesized that vulva and abdominal skin may be especially susceptible to body mass index (BMI)-induced alterations in biophysical properties and the microbiome due increased maceration and skin folds at those sites. The aim of this study was to determine if high BMI (≥30) was associated with alterations in the biophysical properties and microbiomes of vulva and abdominal skin. RESULTS: The vulvar microbial communities of healthy reproductive-aged females were examined using 16S rRNA sequencing techniques. Our results show that vulvar pH of women with high body mass index (BMI) was statistically higher than that of women with average BMI. Phylogenetic analysis of the vulvar microbiota indicated that women with average BMI have a predominately Lactobacillus-dominated flora, whereas women with high BMI and higher pH were predominately colonized by Finegoldia and Corynebacterium. This BMI-associated shift in microbiota was not observed in samples collected from the exposed skin around the belly, indicating the effect is not global. CONCLUSION: These results indicate that physiological changes associated with changes in BMI may modulate the vulva microbiome.

A systems biology approach investigating the effect of probiotics on the vaginal microbiome and host responses in a double blind, placebo-controlled clinical trial of post-menopausal women.

UNLABELLED: A lactobacilli dominated microbiota in most pre and post-menopausal women is an indicator of vaginal health. The objective of this double blinded, placebo-controlled crossover study was to evaluate in 14 post-menopausal women with an intermediate Nugent score, the effect of 3 days of vaginal administration of probiotic L. rhamnosus GR-1 and L. reuteri RC-14 (2.5×109 CFU each) on the microbiota and host response. The probiotic treatment did not result in an improved Nugent score when compared to when placebo. Analysis using 16S rRNA sequencing and metabolomics profiling revealed that the relative abundance of Lactobacillus was increased following probiotic administration as compared to placebo, which was weakly associated with an increase in lactate levels. A decrease in Atopobium was also observed. Analysis of host responses by microarray showed the probiotics had an immune-modulatory response including effects on pattern recognition receptors such as TLR2 while also affecting epithelial barrier function. This is the first study to use an interactomic approach for the study of vaginal probiotic administration in post-menopausal women. It shows that in some cases multifaceted approaches are required to detect the subtle molecular changes induced by the host to instillation of probiotic strains. TRIAL REGISTRATION: ClinicalTrials.gov NCT02139839.

In vitro prediction of in vivo skin damage associated with the wiping of dry tissue against skin.

BACKGROUND: The ideal gentle cleansing product is one that effectively removes soils while minimizing damage to the skin. Thus, measuring physical abrasion caused by cleansing tissues is critical to the continued development of gentle cleansing products. Current analysis of cleansing materials for skin gentleness is time consuming and requires expensive human subject testing. This report describes the development of a rapid and inexpensive bench assay for the assessment of skin abrasion caused by wiping. METHODS: Coefficient of friction (COF) evaluations using bench methods were compared with results from clinical studies of repeated wiping and with confocal visualizations of excised skin. A Monitor/Slip and Friction instrument (model 32-06; TMI, Amityville, NY, USA) was used to measure tissue friction on simulated skin (Vitro-Skin, N19-5X; IMS, Milford, CT, USA). Clinical data from a 4-day repetitive forearm wiping study measuring transepidermal water loss (TEWL) in 30 subjects was compared with results from the bench top assay. In addition, excised skin samples were also treated using the COF bench assay and examined using confocal microscopy to visualize stratum corneum damage caused by wiping. RESULTS: Using the bench COF assay, we were able to distinguish between bath tissue codes by comparing average static friction value (ASFV) for the test codes, where lower ASFV indicated less abrasive tissue. The ASFV followed the same gentleness trend observed in the clinical study. Confocal microscopy of excised skin wiped with the same materials indicated stratum corneum damage consistent with the bench COF and clinical TEWL observations. CONCLUSION: We observed significant correlation between bench and clinical methods for measuring skin damage caused by wiping of skin with tissue. The bench method will facilitate rapid and inexpensive skin gentleness assessment of cleansing materials.

Vaginal microbiome and epithelial gene array in post-menopausal women with moderate to severe dryness.

After menopause, many women experience vaginal dryness and atrophy of tissue, often attributed to the loss of estrogen. An understudied aspect of vaginal health in women who experience dryness due to atrophy is the role of the resident microbes. It is known that the microbiota has an important role in healthy vaginal homeostasis, including maintaining the pH balance and excluding pathogens. The objectives of this study were twofold: first to identify the microbiome of post-menopausal women with and without vaginal dryness and symptoms of atrophy; and secondly to examine any differences in epithelial gene expression associated with atrophy. The vaginal microbiome of 32 post-menopausal women was profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Sixteen subjects were selected for follow-up sampling every two weeks for 10 weeks. In addition, 10 epithelial RNA samples (6 healthy and 4 experiencing vaginal dryness) were acquired for gene expression analysis by Affymetrix Human Gene array. The microbiota abundance profiles were relatively stable over 10 weeks compared to previously published data on premenopausal women. There was an inverse correlation between Lactobacillus ratio and dryness and an increased bacterial diversity in women experiencing moderate to severe vaginal dryness. In healthy participants, Lactobacillus iners and L. crispatus were generally the most abundant, countering the long-held view that lactobacilli are absent or depleted in menopause. Vaginal dryness and atrophy were associated with down-regulation of human genes involved in maintenance of epithelial structure and barrier function, while those associated with inflammation were up-regulated consistent with the adverse clinical presentation.

Chemokine stimulation promotes enterocyte migration through laminin-specific integrins.

Intestinal homeostasis is regulated in part by the single cell layer of the mucosal epithelium. This physical barrier is a prominent part of the innate immune system and possesses an intrinsic ability to heal damage and limit infection. The restitutive epithelial migration phase of healing requires dynamic integrin adhesion to the extracellular matrix. Previously, we have shown that the homeostatic chemokine CXCL12 utilizes intracellular calcium to increase enterocyte migration on laminin. The aim of these studies was to investigate integrin specificity and, in turn, functional responses elicited by CXCL12 stimulation. Analysis of cellular adhesion and spreading revealed CXCL12 preferentially activated laminin-specific integrins compared with collagen IV-binding integrins. Laminin-specific cell adhesion and spreading elicited by CXCL12 was dependent on intracellular calcium. CXCL12 increased activated ß1-integrins on the surface of epithelial cells compared with untreated cells. RT-PCR confirmed expression of the laminin-binding integrins-α3ß1, -α6ß1, and -α6ß4. Interestingly, shRNA-mediated depletion of laminin-specific α3- or α6-integrin subunits revealed differential functions. α3-Integrin knockdown reduced basal as well as inducible restitution. Depletion of α6-integrin specifically abolished CXCL12-stimulated, but not TGF-ß1 or basal, migration. Depletion with either shα3-integrin or shα6-integrin prevented CXCL12-evoked cell spreading. Our data indicate that CXCL12 stimulates the inside-out activation of laminin-specific integrins to promote cell migratory functions. Together, our findings support the notion that extracellular mediators within the gastrointestinal mucosa coordinate cell-matrix interactions during epithelial restitution.

Targeted intestinal epithelial deletion of the chemokine receptor CXCR4 reveals important roles for extracellular-regulated kinase-1/2 in restitution.

Barrier defects and/or alterations in the ability of the gut epithelium to repair itself are critical etiological mechanisms of gastrointestinal disease. Our ongoing studies indicate that the chemokine receptor CXCR4 and its cognate ligand CXCL12 regulate intestinal-epithelial barrier maturation and restitution in cell culture models. Gene-deficient mice lacking CXCR4 expression specifically by the cells of the intestinal epithelium were used to test the hypothesis that CXCR4 regulates mucosal barrier integrity in vivo. Epithelial expression of CXCR4 was assessed by RT-PCR, Southern blot, immunoblot and immunohistochemistry. In vivo wounding assays were performed by addition of 3% dextran sodium sulfate (DSS) in drinking water for 5 days. Intestinal damage and DAI scores were assessed by histological examination. Extracellular-regulated kinase (ERK) phosphorylation was assessed in vivo by immunoblot and immunofluorescence. CXCR4 knockdown cells were established using a lentiviral approach and ERK phosphorylation was assessed. Consistent with targeted roles in restitution, epithelium from patients with inflammatory bowel disease indicated that CXCR4 and CXCL12 expression was stable throughout the human colonic epithelium. Conditional CXCR4-deficient mice developed normally, with little phenotypic differences in epithelial morphology, proliferation or migration. Re-epithelialization was absent in CXCR4 conditional knockout mice following acute DSS-induced inflammation. In contrast, heterozygous CXCR4-depleted mice displayed significant improvement in epithelial ulcer healing in acute and chronic inflammation. Mucosal injury repair was correlated with ERK1/2 activity and localization along the crypt-villus axis, with heterozygous mice characterized by increased ERK1/2 activation. Lentiviral depletion of CXCR4 in IEC-6 cells similarly altered ERK1/2 activity and prevented chemokine-stimulated migration. Taken together, these data indicate that chemokine receptors participate in epithelial barrier responses through coordination of the ERK1/2 signaling pathway.

Calcium mobilization triggered by the chemokine CXCL12 regulates migration in wounded intestinal epithelial monolayers.

Restitution of intestinal epithelial barrier damage involves the coordinated remodeling of focal adhesions in actively migrating enterocytes. Defining the extracellular mediators and the intracellular signaling pathways regulating those dynamic processes is a key step in developing restitution-targeted therapies. Previously we have determined that activation of the chemokine receptor CXCR4 by the cognate ligand CXCL12 enhances intestinal epithelial restitution through reorganization of the actin cytoskeleton. The aim of these studies was to investigate the role of calcium effectors in CXCL12-mediated restitution. CXCL12 stimulated release of intracellular calcium in a dose-dependent manner. Inhibition of intracellular calcium flux impaired CXCL12-mediated migration of IEC-6 and CaCo2 cells. Pharmacological blockade and specific shRNA depletion of the phospholipase-C (PLCbeta3) isoform attenuated CXCL12-enhanced migration, linking receptor activation with intracellular calcium flux. Immunoblot analyses demonstrated CXCL12 activated the calcium-regulated focal adhesion protein proline-rich tyrosine kinase-2 (Pyk2) and the effector proteins paxillin and p130(Cas). Interruption of Pyk2 signaling potently blocked CXCL12-induced wound closure. CXCL12-stimulated epithelial cell migration was enhanced on laminin and abrogated by intracellular calcium chelation. These results suggest CXCL12 regulates restitution through calcium-activated Pyk2 localized to active focal adhesions. Calcium signaling pathways may therefore provide a novel avenue for enhancing barrier repair.

CCR6 regulation of the actin cytoskeleton orchestrates human beta defensin-2- and CCL20-mediated restitution of colonic epithelial cells.

Intestinal inflammation is exacerbated by defects in the epithelial barrier and subsequent infiltration of microbes and toxins into the underlying mucosa. Production of chemokines and antimicrobial peptides by an intact epithelium provide the first line of defense against invading organisms. In addition to its antimicrobial actions, human beta defensin-2 (HBD2) may also stimulate the migration of dendritic cells through binding the chemokine receptor CCR6. As human colonic epithelium expresses CCR6, we investigated the potential of HBD2 to stimulate intestinal epithelial migration. Using polarized human intestinal Caco2 and T84 cells and non-transformed IEC6 cells, HBD2 was equipotent to CCL20 in stimulating migration. Neutralizing antibodies confirmed HBD2 and CCL20 engagement to CCR6 were sufficient to induce epithelial cell migration. Consistent with restitution, motogenic concentrations of HBD2 and CCL20 did not induce proliferation. Stimulation with those CCR6 ligands leads to calcium mobilization and elevated active RhoA, phosphorylated myosin light chain, and F-actin accumulation. HBD2 and CCL20 were unable to stimulate migration in the presence of either Rho-kinase or phosphoinositide 3-kinase inhibitors or an intracellular calcium chelator. Together, these data indicate that the canonical wound healing regulatory pathway, along with calcium mobilization, regulates CCR6-directed epithelial cell migration. These findings expand the mechanistic role for chemokines and HBD2 in mucosal inflammation to include immunocyte trafficking and killing of microbes with the concomitant activation of restitutive migration and barrier repair.

Constitutive CXCL12 expression induces anoikis in colorectal carcinoma cells.

BACKGROUND & AIMS: CXCL12 and CXCR4 signaling plays critical roles in development, homeostasis, and tumor metastasis. Previously, we have shown that epigenetic silencing of CXCL12 in colorectal and mammary carcinomas promotes metastasis. Anoikis is an essential process of colonic epithelial turnover and limits the metastatic progression of carcinoma. We sought to determine the role for anoikis in limiting tumor metastasis following reexpression of CXCL12 in human colorectal carcinoma cells. METHODS: Tumor formation and metastasis of colonic carcinoma cells was monitored using in vivo bioluminescence imaging. Anoikis was defined by using caspase-3/7, focal adhesion kinase (FAK) and p130Cas cleavage, DNA fragmentation, and cell survival assays. Phosphorylation of extracellular-regulated kinase-1/2 (ERK1/2) was monitored by immunoblot and immunohistochemistry, and activity was inhibited by using U0126. RESULTS: Constitutive expression of CXCL12 in human colorectal carcinoma cells reduced orthotopic tumor formation and inhibited metastasis in severe combined immunodeficient mice. Further, CXCL12 expression induced apoptosis specifically in nonadherent colorectal carcinoma cells. Apoptotic cell death was preceded by hypophosphorylation and cleavage of FAK and p130Cas, leading to increased cellular detachment in culture, and depended on alterations in the extracellular matrix. Similar to in vivo colonic epithelium, CXCL12-induced anoikis of carcinoma cells depended on basal ERK1/2 activation. CONCLUSIONS: These data significantly expand the current paradigm of chemokine signaling in carcinogenesis by showing that endogenous CXCL12, in marked contrast to exogenous ligand, inhibits tumor metastasis through increased anoikis. Altered ERK1/2 signaling provides a mechanism for the dichotomy between the physiologic and pathophysiologic roles of CXCL12-CXCR4 signaling in the intestinal epithelium.

Chemokines and chemokine receptors in mucosal homeostasis at the intestinal epithelial barrier in inflammatory bowel disease.

Chemokines, a large family of small chemoattractive cytokines, and their receptors play an integral role in the regulation of the immune response and homeostasis. The ability of chemokines to attract specific populations of immune cells sets them apart from other chemoattractants. Chemokines produced within the gastrointestinal mucosa are critical players in directing the balance between physiological and pathophysiological inflammation in health, inflammatory bowel disease (IBD), and the progression to colon cancer. In addition to the well-characterized role of chemokines in directed trafficking of immune cells to the gut mucosa, the expression of chemokine receptors on the cells of the epithelium makes them active participants in the chemokine signaling network. Recent findings demonstrate an important role for chemokines and chemokine receptors in epithelial barrier repair and maintenance as well as an intricate involvement in limiting metastasis of colonic carcinoma. Increased recognition of the association between barrier defects and inflammation and the subsequent progression to cancer in IBD thus implicates chemokines as key regulators of mucosal homeostasis and disease pathogenesis.