Expression of the membrane tetraspanin claudin 18 on cancer cells promotes T lymphocyte infiltration and antitumor immunity in pancreatic cancer.

Tumors weakly infiltrated by T lymphocytes poorly respond to immunotherapy. We aimed to unveil malignancy-associated programs regulating T cell entrance, arrest, and activation in the tumor environment. Differential expression of cell adhesion and tissue architecture programs, particularly the presence of the membrane tetraspanin claudin (CLDN)18 as a signature gene, demarcated immune-infiltrated from immune-depleted mouse pancreatic tumors. In human pancreatic ductal adenocarcinoma (PDAC) and non-small cell lung cancer, CLDN18 expression positively correlated with more differentiated histology and favorable prognosis. CLDN18 on the cell surface promoted accrual of cytotoxic T lymphocytes (CTLs), facilitating direct CTL contacts with tumor cells by driving the mobilization of the adhesion protein ALCAM to the lipid rafts of the tumor cell membrane through actin. This process favored the formation of robust immunological synapses (ISs) between CTLs and CLDN18-positive cancer cells, resulting in increased T cell activation. Our data reveal an immune role for CLDN18 in orchestrating T cell infiltration and shaping the tumor immune contexture.

Extracellular vesicles from adipose mesenchymal stem cells target inflamed lymph nodes in experimental autoimmune encephalomyelitis.

BACKGROUND AIMS: Adipose mesenchymal stem cells (ASCs) represent a promising therapeutic approach in inflammatory neurological disorders, including multiple sclerosis (MS). Recent lines of evidence indicate that most biological activities of ASCs are mediated by the delivery of soluble factors enclosed in extracellular vesicles (EVs). Indeed, we have previously demonstrated that small EVs derived from ASCs (ASC-EVs) ameliorate experimental autoimmune encephalomyelitis (EAE), a murine model of MS. The precise mechanisms and molecular/cellular target of EVs during EAE are still unknown. METHODS: To investigate the homing of ASC-EVs, we intravenously injected small EVs loaded with ultra-small superparamagnetic iron oxide nanoparticles (USPIO) at disease onset in EAE-induced C57Bl/6J mice. Histochemical analysis and transmission electron microscopy were carried out 48 h after EV treatment. Moreover, to assess the cellular target of EVs, flow cytometry on cells extracted ex vivo from EAE mouse lymph nodes was performed. RESULTS: Histochemical and ultrastructural analysis showed the presence of labeled EVs in lymph nodes but not in lungs and spinal cord of EAE injected mice. Moreover, we identified the cellular target of EVs in EAE lymph nodes by flow cytometry: ASC-EVs were preferentially located in macrophages, with a consistent amount also noted in dendritic cells and CD4+ T lymphocytes. CONCLUSIONS: This represents the first direct evidence of the privileged localization of ASC-EVs in draining lymph nodes of EAE after systemic injection. These data provide prominent information on the distribution, uptake and retention of ASC-EVs, which may help in the development of EV-based therapy in MS.

Supramolecular Hydrogels and Water Channels of Differing Diameters from Dipeptide Isomers.

Dipeptides stereoisomers and regioisomers composed of norleucine (Nle) and phenylalanine (Phe) self-assemble into hydrogels under physiological conditions that are suitable for cell culture. The supramolecular behavior, however, differs as the packing modes comprise amphipathic layers or water channels, whose diameter is defined by either four or six dipeptide molecules. A variety of spectroscopy, microscopy, and synchrotron-radiation-based techniques unveil fine details of intermolecular interactions that pinpoint the relationship between the chemical structure and ability to form supramolecular architectures that define soft biomaterials.

TIM-1 glycoprotein binds the adhesion receptor P-selectin and mediates T cell trafficking during inflammation and autoimmunity.

Selectins play a central role in leukocyte trafficking by mediating tethering and rolling on vascular surfaces. Here we have reported that T cell immunoglobulin and mucin domain 1 (TIM-1) is a P-selectin ligand. We have shown that human and murine TIM-1 binds to P-selectin, and that TIM-1 mediates tethering and rolling of T helper 1 (Th1) and Th17, but not Th2 and regulatory T cells on P-selectin. Th1 and Th17 cells lacking the TIM-1 mucin domain showed reduced rolling in thrombin-activated mesenteric venules and inflamed brain microcirculation. Inhibition of TIM-1 had no effect on naive T cell homing, but it reduced T cell recruitment in a skin hypersensitivity model and blocked experimental autoimmune encephalomyelitis. Uniquely, the TIM-1 immunoglobulin variable domain was also required for P-selectin binding. Our data demonstrate that TIM-1 is a major P-selectin ligand with a specialized role in T cell trafficking during inflammatory responses and the induction of autoimmune disease.

A Double-Walled Tetrahedron with AgI 4 Vertices Binds Different Guests in Distinct Sites.

A double-walled tetrahedral metal-organic cage assembled in solution from silver(I), 2-formyl-1,8-naphthyridine, halide, and a threefold-symmetric triamine. The AgI 4 X clusters at its vertices each bring together six naphthyridine-imine moieties, leading to a structure in which eight tritopic ligands bridge four clusters in an (AgI 4 X)4 L8 arrangement. Four ligands form an inner set of tetrahedron walls that are surrounded by the outer four. The cage has significant interior volume, and was observed to bind anionic guests. The structure also possesses external binding clefts, located at the edges of the cage, which bound small aromatic guests. Halide ions bound to the silver clusters were observed to exchange in a well-defined hierarchy, allowing modulation of the cavity volume. The principles uncovered here may allow for increasingly more sophisticated cages with silver-cluster vertex architectures, with post-assembly tuning of the interior cavity volume enabling targeted binding behavior.

Regulation of leukocyte recruitment by the long pentraxin PTX3.

Pentraxins are a superfamily of conserved proteins involved in the acute-phase response and innate immunity. Pentraxin 3 (PTX3), a prototypical member of the long pentraxin subfamily, is a key component of the humoral arm of innate immunity that is essential for resistance to certain pathogens. A regulatory role for pentraxins in inflammation has long been recognized, but the underlying mechanisms remain unclear. Here we report that PTX3 bound P-selectin and attenuated neutrophil recruitment at sites of inflammation. PTX3 released from activated leukocytes functioned locally to dampen neutrophil recruitment and regulate inflammation. Antibodies have glycosylation-dependent regulatory effect on inflammation. Therefore, PTX3, which is an essential component of humoral innate immunity, and immunoglobulins share functional outputs, including complement activation, opsonization and, as shown here, glycosylation-dependent regulation of inflammation.

Single-atom substitution enables supramolecular diversity from dipeptide building blocks.

Dipeptides are popular building blocks for supramolecular gels that do not persist in the environment and may find various applications. In this work, we show that a simple substitution on the aromatic side-chain of phenylalanine with either fluorine or iodine enables supramolecular diversity upon self-assembly at neutral pH, leading to hydrogels or crystals. Each building block is characterized by 1H- and 13C-NMR spectroscopy, LC-MS, circular dichroism, and molecular models. The supramolecular behaviour is monitored with a variety of techniques, including circular dichroism, oscillatory rheology, transmission electron microscopy, attenuated total reflectance Fourier-transformed infrared spectroscopy, visible Raman spectroscopy, synchrotron-radiation single-crystal X-ray diffraction and UV Resonance Raman spectroscopy, allowing key differences to be pinpointed amongst the halogenated analogues.

UV resonance Raman spectroscopy of weakly hydrogen-bonded water in the liquid phase and on ice and snow surfaces.

The hydrogen bond network has a major role in determining the physical and chemical properties of water both in the solid and in the liquid state. In the bulk liquid phase, there is a coexistence of water molecules with different degrees of coordination and their relative amount changes according to the conditions (e.g., temperature, presence of solutes). Ice shows a larger amount of topologically under-coordinated water molecules at the surface as compared to the bulk. Snow is composed of many ice crystallites, and it differs from bulk ice because of the much larger specific surface area. The OH-stretching band is the most intense signal of the Raman spectrum of water, and it gives direct insight about the hydrogen bond network. In this work we compared the OH-stretching region of the Raman spectra of water, ice and snow acquired with excitations in the visible (532 nm) and in the UV-C range (250-200 nm) by exploiting the tunability of the synchrotron radiation. By moving towards the highest energy excitation we observed in liquid water a monotonic increase of the relative intensities of the peaks associated with weakly hydrogen-bonded water molecules. With visible excitation, the Raman spectrum of snow displays a larger contribution from weakly hydrogen-bonded water molecules at the surfaces when compared to the spectrum of bulk ice. By using excitation sources in the UV-C range, we observe a further enhancement of the contribution of the surfaces in the spectra of snow. By considering the reported changes of the water absorption coefficient in relation to the hydrogen bonding environment, we interpreted our results as a preferential pre-resonance excitation of weakly hydrogen-bonded water molecules induced by the UV-C sources.

Solvent Vibrations as a Proxy of the Telomere G-Quadruplex Rearrangements across Thermal Unfolding.

G-quadruplexes (G4s) are noncanonical forms of DNA involved in many key genome functions. Here, we exploited UV Resonance Raman scattering to simultaneously explore the vibrational behavior of a human telomeric G4 (Tel22) and its aqueous solvent as the biomolecule underwent thermal melting. We found that the OH stretching band, related to the local hydrogen-bonded network of a water molecule, was in strict relation with the vibrational features of the G4 structure as a function of temperature. In particular, the modifications to the tetrahedral ordering of the water network were strongly coupled to the DNA rearrangements, showing changes in temperature that mirrored the multi-step melting process of Tel22. The comparison between circular dichroism and Raman results supported this view. The present findings provide novel insights into the impact of the molecular environment on G4 conformation. Improving current knowledge on the solvent structural properties will also contribute to a better understanding of the role played by water arrangement in the complexation of G4s with ligands.

Comparative life cycle cost assessment of (lean) duplex stainless steel in wastewater treatment environments.

Some unit operations in wastewater treatment plants (WWTPs), such as settling tanks and pipes for aeration or sludge transfer, are composed of austenitic stainless steel (EN 1.4307 or EN 1.4404) instead of galvanised or painted carbon steel to reduce the maintenance costs. The sensitivity to pitting and crevice corrosion of austenitic grades in certain WWTP environments has also led to the use of duplex grades. The purpose of this study is to evaluate the maintenance of piping systems (WWTPs) and its effect on their life cycle environmental impacts and costs (LCC) for both austenitic and duplex stainless steel grades. The final objective is to aid grade selection for piping in a WWTP environment. The considered functional unit (FU) is a complete piping system. Conventional austenitic stainless steel grades (e.g., EN 1.4404) are studied alongside duplex ones (e.g., EN 1.4362 and EN 1.4462). The calculated environmental impacts are the Global Warming Potential (GWP) and Primary Energy Demand (PED). The production, manufacturing, transport, use including maintenance activities, and end-of-life (burdens and credits) phases are included in the life cycle assessment (LCA). The maintenance activities consist of the required replacements of stainless steel piping during the lifespan of the WWTP. Thus, the service lives of the pipes included in the considered WWTP environment are determined based on long-term corrosion prediction models (power law), which predict the evolution of pit or crevice depth as a function of time. The model parameters are estimated based on own experimental results, supplemented by the existing literature. The corrosion rates determine the number and frequency of replacements, i.e., define the different scenarios of maintenance. The LCA, LCC and corrosion prediction models are then combined into a user-friendly tool, which can be used in industry for an appropriate grade selection for pipes in a WWTP environment. The tool includes several degrees of freedom such as piping distribution, water pressure, chloride content, replacement criteria, etc. The results show that using duplex stainless steel grade EN 1.4462 leads to lower GWP and PED at the end of the WWTP's service life of 40 years. This is mainly due to multiple replacements of the system's parts in wastewater with high levels of chloride (>3000 ppm) if more conventional austenitic stainless steel alloys such as EN 1.4404 are used. Leaner duplex stainless steel grades were also included in this LCC assessment. The duplex grade EN 1.4062 showed the lowest total LCC, thanks to its leaner chemical composition (i.e., lower nickel content) combined with good localized corrosion resistance.

Regulation of conformer-specific activation of the integrin LFA-1 by a chemokine-triggered Rho signaling module.

Regulation of the affinity of the beta(2) integrin LFA-1 by chemokines is critical to lymphocyte trafficking, but the signaling mechanisms that control this process are not well understood. Here we investigated the signaling events controlling LFA-1 affinity triggering by chemokines in human primary T lymphocytes. We found that the small GTPase Rac1 mediated chemokine-induced LFA-1 affinity triggering and lymphocyte arrest in high endothelial venules. Unexpectedly, another Rho family member, Cdc42, negatively regulated LFA-1 activation. The Rho effectors PLD1 and PIP5KC were also critical to LFA-1 affinity modulation. Notably, PIP5KC was found to specifically control the transition of LFA-1 from an extended low-intermediate state to a high-affinity state, which correlated with lymphocyte arrest. Thus, chemokines control lymphocyte trafficking by triggering a Rho-dependent signaling cascade leading to conformer-specific modulation of LFA-1 affinity.

Dispersions of Zirconia Nanoparticles Close to the Phase Boundary of Surfactant-Free Ternary Mixtures.

The achievement of a homogeneous dispersion of nanoparticles is of paramount importance in supporting their technological application. In wet processing, stable dispersions were largely obtained via surfactant or surface functionalization: although effective, the use of dispersant can alter, or even impair, the functional properties of the resulting nanostructured systems. Herein, we report a novel integrated modeling and experimental approach to obtain stable ZrO2 nanoparticle (NP) dispersions at native dimensions (about 5 nm) in homogeneous ternary mixtures of solvents (i.e., water, ethanol, and 1,2-dichlorobenzene) without any further surface functionalization. A miscibility ternary diagram was computed exploiting the universal quasi-chemical functional-group activity coefficient (UNIFAC) model, which was then experimentally validated. Dynamic light scattering (DLS) on these mixtures highlights that nanometric structures, resembling nanoemulsion droplets, form close to the mixture two-phase boundary, with a size that depends on the ternary mixture composition. ZrO2-NPs were then synthesized following a classic sol-gel approach and characterized by XRD and Raman spectroscopy. ZrO2-NPs were dispersed in HCl and mixed with different mixtures of ethanol and 1,2-dichlorobenzene (DCB), obtaining homogeneous and stable dispersions. These dispersions were then studied by means of DLS as a function of DCB concentration, observing that the nanoparticles can be dispersed at their native dimensions when the mass fraction of DCB was lower than 60%, whereas the increase of the hydrophobic solvent leads to the NPs' agglomeration and sedimentation. The proposed approach not only offers specific guidelines for the design of ZrO2-NPs dispersions in a ternary solvent mixture but can also be extended to other complex solvent mixtures in order to achieve stable dispersions of nanoparticles with no functionalization.

Insight into the thermal stability of DNA in hydrated ionic liquids from multi-wavelength UV resonance Raman experiments.

The utility of ionic liquids (ILs) as alternative solvents for stabilizing and preserving the native structure of DNA over the long term may be envisaged for biotechnological and biomedical applications in the near future. The delicate balance between the stabilizing and destabilizing effects of IL-mediated interactions with the structure of DNA is complex and is still not well understood. This work reports a fundamental study dealing with the effect exerted by cations and anions in imidazolium-based ILs on the thermal structural stability of large nucleic acid molecules. Multi-wavelength UV resonance Raman spectroscopy is used for selectively detecting heat-induced structural transitions of DNA localized on specific base tracts. Our study reveals the establishment of preferential interactions between the imidazolium cations of ILs and the guanine bases in the DNA groove that lead to more effective stacking between the guanine bases even at high temperatures. Interestingly, we observe that this trend for ILs sharing the same chloride anion is further enhanced as the alkyl chain on the imidazolium cation gets shorter. The results from the present investigation lead to a more comprehensive view of the IL-mediated interactions with A-T and G-C base pairs during thermal unfolding.

Symptoms and their implications on quality of life and psychological distress in sarcoma patients.

The aim of this study was to investigate symptoms, their variation over time and their relationship with quality of life (QoL)/psychological distress in sarcoma patients, as few data regarding QoL and psychological distress in this set of patients are currently available. A total of 188 sarcoma patients from an Italian referral center were involved. Symptoms and financial difficulties were evaluated with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire from the first treatment and over the follow-up period, up to 6 years. The authors found that patients with sarcoma experience several symptoms, especially fatigue and pain, which may dramatically worsen QoL and psychological distress. In conclusion, patients with sarcoma often experience fatigue, pain and financial difficulties, which negatively impacts QoL and psychological distress. To ameliorate overall QoL, proper control of symptoms is necessary.

Fatigue in hemodialysis patients: A single-center cross-sectional study.

BACKGROUND: Fatigue is a highly prevalent condition among people affected by chronic disease, with consequent poor health-related quality of life and lower survival rates. Fatigue is one of the most common and debilitating symptoms also experienced by hemodialysis (HD) patients after HD sessions, and given the non-specific manifestations and its invisible nature, it is under-recognized and under-treated by healthcare professionals. The complexity of fatigue's pathogenesis and the lack of measurement tools make the development of nursing interventions and practices specifically targeted at its recognition and therapy difficult. We aimed to investigate the prevalence and severity of fatigue, identify predictor variables in HD patients, and promote healthcare professionals' awareness and recognition of fatigue. MATERIALS AND METHODS: A single-center, cross-sectional study was conducted among 140 patients treated at the HD unit between August 2019 and March 2020 at the Nephrology, Dialysis, and Transplantation Unit of Padova University Hospital. We assessed patient's fatigue by Chalder's Fatigue Questionnaire, pain by Numeric Rating Scale and activities of daily living by Barthel Index. Demographic and clinical characteristics were taken from medical records. RESULTS: The findings of this study indicate that age, dialysis vintage, inter-dialysis weight gain, and ultra-filtration rate are proportionally related to reported levels of fatigue. Hemoglobin, iron, ferritin, and number of sleep hours before HD session present a significant inverse correlation to fatigue. CONCLUSION: The complexity of fatigue's pathogenesis makes a better understanding of this phenomenon difficult, nevertheless, healthcare professionals should develop interventions and practices targeted at its identification and management.

Going to war with COVID-19: Strategies for SARS-CoV-2 management in the Padua Nephrology and Dialysis Unit's hemodialysis facility.

BACKGROUND: The recent SARS-CoV-2 outbreak represents a global health emergency, and dialysis patients are a high-risk population. Patients with end-stage renal disease (ESRD) in hemodialysis facilities require specific protocols to be planned and promptly executed for the management of suspected/confirmed cases of COVID-19 with respect to prevention, protection, screening, and isolation. MATERIALS AND METHODS: In order to prevent the spread of SARS-CoV-2 in our Hemodialysis Unit, we adopted individual protection measures accompanied by measures to minimize contacts among hemodialysis patients with suspicious symptoms as well as other patients and medical staff. We provided our patients detailed instructions to be followed in the event of their having symptoms compatible with SARS-CoV-2 infection or having contacts with SARS-CoV-2-positive subjects. Ultimately, four possible scenarios and care paths were developed and implemented in collaboration with the Infectious Diseases and Emergency Units at the Padua University Hospital. RESULTS: The application of this strategy has resulted in the nearly 200 patients treated in our hemodialysis facilities while there were only 2 cases of COVID-19 (1% incidence rate) with no deaths. CONCLUSION: We attribute the low COVID-19 incidence noted so far for patients in our hemodialysis facilities to the early detection and prompt isolation of suspected patients per our specific plan along with the prompt application of preventive measures.

Lifecycle cost assessment of high strength carbon and stainless steel girder bridges.

This paper addresses the lifecycle cost assessment of a steel girder bridge considering the material costs and maintenance activities along the bridge's lifecycle. A reference highway bridge case study is chosen. It was initially designed using carbon steel S355. Two more steel grades are included in the comparison: high strength carbon steel S460 and duplex stainless steel EN 1.4162. For each design option, fatigue appears to be the driving design criterion for the following critical welded details: transversal stiffeners, cope holes and full penetration butt welds in the flanges. In addition to ultimate limit state verifications, specific attention is therefore given to fatigue through the use of different verification methods: the well-known nominal stress method and the hot spot stress method. It is concluded that the net present value of the lifecycle cost of the stainless steel option is attractive compared to painted the carbon steel options.

Pilot-scale evaluation of ozone as a polishing step for the removal of nonylphenol from tank truck cleaning wastewater.

The presence of nonylphenol (NP) in the wastewater of the tank truck cleaning industry is a major concern because of its endocrine disruptive properties. In this paper, the use of ozone for degrading NP from tank truck cleaning wastewater was investigated by operating a pilot-scale biological wastewater treatment in combination with an ozonation unit. The impact of the added ozonation step on the removal of NP, soluble chemical oxygen demand (sCOD) and total organic carbon (TOC) was monitored over one year. sCOD and TOC removal were not significantly enhanced, but the NP peak concentrations in the effluent were significantly lower than those obtained after biological treatment only: a relatively low NP concentration was observed, even when peak loads were present in the influent of the pilot-scale biological wastewater treatment plant (influentbio). Contrariwise, the effluent of the sole biological treatment follows the peak load trends of the influentbio. During the ozonation period, the average NP concentration in the combined biological-ozone unit was 0.29 µg/L, compared to 1.89 µg/L for the effluent obtained after a sole biological treatment, resulting in an improved average removal efficiency of 32%.

Effects of increasing dietary level of organic acids and nature-identical compounds on growth, intestinal cytokine gene expression and gut microbiota of rainbow trout (Oncorhynchus mykiss) reared at normal and high temperature.

Organic acids (OA) and nature-identical compounds (NIC) such as monoterpenes and aldehydes are well-known growth and health promoters in terrestrial livestock while their application for fish production is recent and their mechanisms of action require further study. Hence, this study tested the increasing dietary level (D0, D250, D500, D1000; 0, 250, 500 and 1000 mg kg feed-1 respectively) of a microencapsulated blend containing citric and sorbic acid, thymol and vanillin over 82 days on rainbow trout to assess the effects on growth, feed utilization, intestine cytokine gene expression and gut microbiota (GM). Furthermore, the effects on intestinal cytokine gene expression and GM were also explored after one week at high water temperature (23 °C). OA and NIC improved specific growth rate (SGR) and feed conversion rate (FCR) during the second half (day 40-82) of the feeding trial, while at the end of the trial protein (PER) and lipid efficiency (LER) increased with increasing dietary level. GM diversity and composition and cytokine gene expression analysis showed no significant differences in fish fed with increasing doses of OA and NIC (82 days) demonstrating the absence of inflammatory activity in the intestinal mucosa. Although there were no statistical differences, GM structure showed a tendency in clustering D0 group separately from the other dietary groups and a trend towards reduction of Streptococcus spp. was observed in the D250 and D1000 groups. After exposure to high water temperature, lower GM diversity and increased gene expression of inflammatory intestinal cytokines were observed for both inclusions (D0 vs. D1000) compared to groups in standard condition. However, the gene up-regulation involved a limited number of cytokines showing the absence of a substantial inflammation process able to compromise the functional activity of the intestine. Despite further study should be conducted to fully clarify this mechanism, cytokines up-regulation seems to be concomitant to the reduction of the GM diversity and, particularly, to the reduction of specific lactic acid bacteria such as Leuconostoc. The application of the microencapsulate blend tested can be a useful strategy to improve growth and feed utilization in rainbow trout under normal temperature conditions. According to the results organic acids and nature-identical compounds did not revert the effects triggered by the increased temperature of water.

Thymol modulates the endocannabinoid system and gut chemosensing of weaning pigs.

BACKGROUND: The recent identification of the endocannabinoid system in the gastrointestinal tract suggests a role in controlling intestinal inflammation. In addition, the gut chemosensing system has therapeutic applications in the treatment of gastrointestinal diseases and inflammation due to the presence of a large variety of receptors. The purposes of this study were to investigate the presence of markers of the endocannabinoid system and the chemosensing system in the pig gut and, second, to determine if thymol modulates these markers. One hundred sixty 28-day-old piglets were allocated into one of 5 treatment groups (n = 32 per treatment): T1 (control), T2 (25.5 mg thymol/kg feed), T3 (51 mg thymol/kg feed), T4 (153 mg thymol/kg feed), and T5 (510 mg thymol/kg feed). After 14 days of treatment, piglets were sacrificed (n = 8), and then duodenal and ileal mucosal scrapings were collected. Gene expression of cannabinoid receptors (CB1 and CB2), transient receptor potential vanilloid 1 (TRPV1), the olfactory receptor OR1G1, diacylglycerol lipases (DGL-α and DGL-ß), fatty acid amine hydrolase (FAAH), and cytokines was measured, and ELISAs of pro-inflammatory cytokines levels were performed. RESULTS: mRNAs encoding all markers tested were detected. In the duodenum and ileum, the CB1, CB2, TRPV1, and OR1G1 mRNAs were expressed at higher levels in the T4 and T5 groups compared to the control group. The level of the FAAH mRNA was increased in the ileum of the T4 group compared to the control. Regarding the immune response, the level of the tumor necrosis factor (TNF-α) mRNA was significantly increased in the duodenum of the T5 group, but this increase was not consistent with the protein level. CONCLUSIONS: These results indicate the presence of endocannabinoid system and gut chemosensing markers in the piglet gut mucosa. Moreover, thymol modulated the expression of the CB1, CB2, TRPV1, and OR1G1 mRNAs in the duodenum and ileum. It also modulated the mRNA levels of enzymes involved in the biosynthesis and degradation of endocannabinoid molecules. Based on these findings, the effects of thymol on promoting gut health are potentially mediated by the activation of these receptors.