Oleanolic acid improved intestinal immune function by activating and potentiating bile acids receptor signaling in E. coli-challenged piglets.

BACKGROUND: Infection with pathogenic bacteria during nonantibiotic breeding is one of the main causes of animal intestinal diseases. Oleanolic acid (OA) is a pentacyclic triterpene that is ubiquitous in plants. Our previous work demonstrated the protective effect of OA on intestinal health, but the underlying molecular mechanisms remain unclear. This study investigated whether dietary supplementation with OA can prevent diarrhea and intestinal immune dysregulation caused by enterotoxigenic Escherichia coli (ETEC) in piglets. The key molecular role of bile acid receptor signaling in this process has also been explored. RESULTS: Our results demonstrated that OA supplementation alleviated the disturbance of bile acid metabolism in ETEC-infected piglets (P < 0.05). OA supplementation stabilized the composition of the bile acid pool in piglets by regulating the enterohepatic circulation of bile acids and significantly increased the contents of UDCA and CDCA in the ileum and cecum (P < 0.05). This may also explain why OA can maintain the stability of the intestinal microbiota structure in ETEC-challenged piglets. In addition, as a natural ligand of bile acid receptors, OA can reduce the severity of intestinal inflammation and enhance the strength of intestinal epithelial cell antimicrobial programs through the bile acid receptors TGR5 and FXR (P < 0.05). Specifically, OA inhibited NF-κB-mediated intestinal inflammation by directly activating TGR5 and its downstream cAMP-PKA-CREB signaling pathway (P < 0.05). Furthermore, OA enhanced CDCA-mediated MEK-ERK signaling in intestinal epithelial cells by upregulating the expression of FXR (P < 0.05), thereby upregulating the expression of endogenous defense molecules in intestinal epithelial cells. CONCLUSIONS: In conclusion, our findings suggest that OA-mediated regulation of bile acid metabolism plays an important role in the innate immune response, which provides a new diet-based intervention for intestinal diseases caused by pathogenic bacterial infections in piglets.

Protein Transduction System Based on Tryptophan-zipper against Intracellular Infections via Inhibiting Ferroptosis of Macrophages.

Cells penetrating molecules in living systems hold promise of capturing and eliminating threats and damage that can plan intracellular fate promptly. However, it remains challenging to construct cell penetration systems that are physiologically stable with predictable self-assembly behavior and well-defined mechanisms. In this study, we develop a core-shell nanoparticle using a hyaluronic acid (HA)-coated protein transduction domain (PTD) derived from the human immunodeficiency virus (HIV). This nanoparticle can encapsulate pathogens, transporting the PTD into macrophages via lipid rafts. PTD forms hydrogen bonds with the components of the membrane through TAT, which has a high density of positive charges and reduces the degree of membrane order through Tryptophan (Trp)-zipper binding to the acyl tails of phospholipid molecules. HA-encapsulated PTD increases the resistance to trypsin and proteinase K, thereby penetrating macrophages and eliminating intracellular infections. Interestingly, the nonagglutination mechanism of PTD against pathogens ensures the safe operation of the cellular system. Importantly, PTD can activate the critical pathway of antiferroptosis in macrophages against pathogen infection. The nanoparticles developed in this study demonstrate safety and efficacy against Gram-negative and Gram-positive pathogens in three animal models. Overall, this work highlights the effectiveness of the PTD nanoparticle in encapsulating pathogens and provides a paradigm for transduction systems-anti-intracellular infection therapy.

Perceived environmental supports for fruit and vegetable consumption among older adults in the US.

BACKGROUND: The physical and social environments surrounding food, whether perceived or observed, can influence consumers' food choices by changing food access, and affordability, or by changing settings where food-related behaviors occur. AIM: To describe older adults' perceived food environment, identify the most important sites and factors that enable healthy eating, and explore older adults' recommendations for communities to facilitate fruit and vegetable consumption. METHODS: Participants aged 60 and older from metropolitan areas in Massachusetts, Iowa, and Illinois completed a researcher-administered survey to rate the perceived environment including accessibility, availability, and affordability of fruits and vegetables, and perceived importance of factors and establishments related to fruit and vegetable consumption. Participants also suggested changes for establishments to facilitate fruit and vegetable consumption. RESULTS: The majority of the 142 participants perceived their food environment for fruits and vegetables as not difficult to access (85.2%) with good or excellent availability (90.1%). Education, marital status, and race were associated with some aspects of the perceived food environment. Perceived accessibility and supermarkets were rated as the most important factor and establishment, respectively, to facilitate fruit and vegetable consumption across all study sites. Participants proposed recommendations to address the availability, quality, accessibility and affordability of fruits and vegetables. CONCLUSION: Interventions promoting accessible, affordable, quality fruits and vegetables may improve older adult consumers' perceptions of their food environment. Communities may also use undervalued resources such as mobile markets more strategically to provide additional support for healthy eating in older adults.

Community Priorities for Healthy Eating in Older Adults.

Community planners such as policymakers and health care and nutrition service providers can create an "age-friendly" environment to support healthy eating in older residents by addressing the highest priorities that enable older adults to improve their dietary intake through different food-related community settings. To identify and prioritize these factors that facilitate behavioral change (enablers) and behavioral settings important for older adult nutrition based on the social ecological model, nutrition and aging professionals (n = 30) from two rural (West Virginia, Iowa) and two urban (Massachusetts, New York) city/county regions (communities) participated in an online or live focus group discussion and completed an analytic hierarchy process survey online. Overall, the most important perceived enablers were accessibility and cost, followed by transportation and social support, but their relative importance varied by community. Participants from all communities considered congregate meal sites and food banks among the most important behavioral settings. Participants from most communities considered food stores to be important and also highlighted other settings unique to the area, such as senior housing, neighborhood, and farmers' markets. By targeting interventions to address the most notable enablers and behavioral settings specific to their community, planning groups can enhance their older residents' ability to achieve optimal nutritional health.

Identification of environmental supports for healthy eating in older adults.

Many environmental settings and influences can affect food choices and eating behaviors in the growing population of community-dwelling older adults. Using the Social Ecological model, an expert panel participated in online discussions and an Analytic Hierarchy Process survey to identify the most important and changeable environmental settings and enabling factors that promote healthy eating in older adults. Food stores were rated most important when considering accessibility and affordability. Congregate nutrition sites were important for social support along with supporting access and affordability of healthful foods and living accommodations. Senior housing, health care, and religious settings also contributed to the goal of promoting healthful eating in aging adults. Restaurants were rated of lower importance. Based on these results, it is recommended that community food policies include the nutritional needs of older adults by addressing food accessibility and affordability, social support, and living accommodations, with a focus on congregate nutrition sites, food stores, senior housing, health care, and religious organizations.