GILZ as a Regulator of Cell Fate and Inflammation

High expression of L-GILZ transcript variant 1 (GILZ TV 1) is associated with increased 30-day sepsis mortality, and a high expression ratio possibly contraindicates hydrocortisone administration

BACKGROUND

Sepsis presents a challenge due to its complex immune responses, where balance between inflammation and anti-inflammation is critical for survival. Glucocorticoid-induced leucine zipper (GILZ) is key protein in achieving this balance, suppressing inflammation and mediating glucocorticoid response. This study aims to investigate GILZ transcript variants in sepsis patients and explore their potential for patient stratification and optimizing glucocorticoid therapy.

METHODS

Sepsis patients meeting the criteria outlined in Sepsis-3 were enrolled, and RNA was isolated from whole blood samples. Quantitative mRNA expression of GILZ transcript variants in both sepsis patient samples (n = 121) and the monocytic U937 cell line (n = 3), treated with hydrocortisone and lipopolysaccharides, was assessed using quantitative PCR (qPCR).

RESULTS

Elevated expression of GILZ transcript variant 1 (GILZ TV 1) serves as a marker for heightened 30-day mortality in septic patients. Increased levels of GILZ TV 1 within the initial day of sepsis onset are associated with a 2.2-[95% CI 1.2-4.3] fold rise in mortality, escalating to an 8.5-[95% CI 2.0-36.4] fold increase by day eight. GILZ TV1 expression is enhanced by glucocorticoids in cell culture but remains unaffected by inflammatory stimuli such as LPS. In septic patients, GILZ TV 1 expression increases over the course of sepsis and in response to hydrocortisone treatment. Furthermore, a high expression ratio of transcript variant 1 relative to all GILZ mRNA TVs correlates with a 2.3-fold higher mortality rate in patients receiving hydrocortisone treatment.

CONCLUSION

High expression of GILZ TV 1 is associated with a higher 30-day sepsis mortality rate. Moreover, a high expression ratio of GILZ TV 1 relative to all GILZ transcript variants is a parameter for identifying patient subgroups in which hydrocortisone may be contraindicated.

Reprofiling synthetic glucocorticoid-induced leucine zipper fusion peptide as a novel and effective hair growth promoter

Hair is a biofilament with unique multi-dimensional values. In human, in addition to physiologic impacts, hair loss and hair related disorders can affect characteristic features, emotions, and social behaviors. Despite significant advancement, there is a dire need to explore alternative novel therapies with higher efficacy, less side effects and lower cost to promote hair growth to treat hair deficiency. Glucocorticoid-induced leucine zipper (GILZ) is a protein rapidly induced by glucocorticoids. Studies from our group and many others have suggested that a synthetic form of GILZ, TAT-GILZ, a fusion peptide of trans-activator of transcription and GILZ, can function as a potent regulator of inflammatory responses, re-establishing and maintaining the homeostasis. In this study, we investigate whether TAT-GILZ could promote and contribute to hair growth. For our pre-clinical model, we used 9-12 week-old male BALB/c and nude (athymic, nu/J) mice. We applied TAT-GILZ and/or TAT (vehicle) intradermally to depilated/hairless mice. Direct observation, histological examination, and Immunofluorescence imaging were used to assess the effects and compare different treatments. In addition, we tested two current treatment for hair loss/growth, finasteride and minoxidil, for optimal evaluation of TAT-GILZ in a comparative fashion. Our results showed, for the first time, that synthetic TAT-GILZ peptide accelerated hair growth on depilated dorsal skin of BALB/c and induced hair on the skin of athymic mice where hair growth was not expected. In addition, TAT-GILZ was able to enhance hair follicle stem cells and re-established the homeostasis by increasing counter inflammatory signals including higher regulatory T cells and glucocorticoid receptors. In conclusion, our novel findings suggest that reprofiling synthetic TAT-GILZ peptide could promote hair growth by increasing hair follicle stem cells and re-establishing homeostasis.

Resolution pharmacology and the treatment of infectious diseases

Inflammation is elicited by the host in response to microbes, and is believed to be essential for protection against infection. However, we have previously hypothesized that excessive or misplaced inflammation may be a major contributor to tissue dysfunction and death associated with viral and bacterial infections. The resolutive phase of inflammation is a necessary condition to achieve homeostasis after acute inflammation. It is possible that targeting inflammation resolution may be beneficial for the host during infection. In this review, we summarize the evidence demonstrating the expression, roles and effects of the best described pro-resolving molecules in the context of bacterial and viral infections. Pro-resolving molecules play a pivotal role in modulating a spectrum of pathways associated with tissue inflammation and damage during both viral and bacterial infections. These molecules offer a blend of anti-inflammatory, pro-resolving and sometimes anti-infective benefits, all the while circumventing the undesired and immune-suppressive unwanted effects associated with glucocorticoids. Whether these beneficial effects will translate into benefits to patients clearly deserve further investigation.

The Association between the rs3747406 Polymorphism in the Glucocorticoid-Induced Leucine Zipper Gene and Sepsis Survivals Depends on the SOFA Score

The variability in mortality in sepsis could be a consequence of genetic variability. The glucocorticoid system and the intermediate TSC22D3 gene product-glucocorticoid-induced leucine zipper-are clinically relevant in sepsis, which is why this study aimed to clarify whether TSC22D3 gene polymorphisms contribute to the variance in sepsis mortality. Blood samples for DNA extraction were obtained from 455 patients with a sepsis diagnosis according to the Sepsis-III criteria and from 73 control subjects. A SNP TaqMan assay was used to detect single-nucleotide polymorphisms (SNPs) in the TSC22D3 gene. Statistical and graphical analyses were performed using the SPSS Statistics and GraphPad Prism software. C-allele carriers of rs3747406 have a 2.07-fold higher mortality rate when the sequential organ failure assessment (SOFA) score is higher than eight. In a multivariate COX regression model, the SNP rs3747406 with a SOFA score ≥ 8 was found to be an independent risk factor for 30-day survival in sepsis. The HR was calculated to be 2.12, with a p-value of 0.011. The wild-type allele was present in four out of six SNPs in our cohort. The promoter of TSC22D3 was found to be highly conserved. However, we discovered that the C-allele of rs3747406 poses a risk for sepsis mortality for SOFA Scores higher than 6.

Effects of acute exercise and training status on glucocorticoid-induced leucine zipper (GILZ) expression in human skeletal muscle

Interactions between statin therapy and physical exercise complicate effective cardiovascular prevention. Emerging evidence suggests that muscle strain related changes in the expression of the glucocorticoid-induced leucine zipper (GILZ) may be involved. Therefore, we measured GILZ mRNA expression levels in M. vastus lateralis samples of 32 healthy individuals before and after a standardized bout of strength or endurance exercise. Overall, we found a highly significant downregulation of GILZ after exercise training (p < 0.001). Within-subgroup changes were statistically significant only after strength training, supporting the role of muscle (as opposed to cardiocirculatory) strain. If confirmed, this may help fitting training recommendations and medication.

Systematic Review and Quantitative Data Synthesis of Peripheral Blood Mononuclear Cell Transcriptomics Reveals Consensus Gene Expression Changes in Response to a High Fat Meal

SCOPE

Metabolic flexibility is essential for a healthy response to a high fat meal, and is assessed by measuring postprandial changes in blood markers including peripheral blood mononuclear cells (PBMCs; lymphocytes and monocytes). However, there is no clear consensus on postprandial gene expression and protein changes in these cells.

METHOD AND RESULTS

The study systematically reviews the literature reporting transcriptional and proteomic changes in PBMCs after consumption of a high fat meal. After re-analysis of the raw data to ensure equivalence between studies, ≈85 genes are significantly changed (defined as in the same direction in ≥3 studies) with about half involved in four processes: inflammation/oxidative stress, GTP metabolism, apoptosis, and lipid localization/transport. For meals consisting predominantly of unsaturated fatty acids (UFA), notable additional processes are phosphorylation and glucocorticoid response. For saturated fatty acids (SFA), genes related to migration/angiogenesis and platelet aggregation are also changed.

CONCLUSION

Despite differences in study design, common gene changes are identified in PBMCs following a high fat meal. These common genes and processes will facilitate definition of the postprandial transcriptome as part of the overall postcibalome, linking all molecules and processes that change in the blood after a meal.

Role of histamine H4 receptor in the anti-inflammatory pathway of glucocorticoid-induced leucin zipper (GILZ) in a model of lung fibrosis

INTRODUCTION

This study investigates the interactions between histaminergic system and glucocorticoid-induced leucin zipper (GILZ) in the inflammatory process and glucocorticoid modulation in lung fibrosis.

METHODS

Wild-type (WT) and GILZ Knock-Out (KO) mice were treated with bleomycin (0.05 IU) or saline, delivered by intra-tracheal injection. After surgery, mice received a continuous infusion of JNJ7777120 (JNJ, 2 mg/kg b.wt.) or vehicle for 21 days. Lung function was studied by measuring airway resistance to air insufflation through the analysis of pressure at airway opening (PAO). Lung samples were collected to evaluate the expression of histamine H4R, Anx-A1, and p65-NF-kB, the activity of myeloperoxidase (MPO), and the production of pro-inflammatory cytokines.

RESULTS

Airway fibrosis and remodeling were assessed by measuring TGF-β production and α-SMA deposition. JNJ reduces PAO in WT but not in GILZ KO mice (from 22 ± 1 mm to 15 ± 0.5 and from 24 ± 1.5 to 19 ± 0.5 respectively), MPO activity (from 204 ± 3.13 pmol/mg to 73.88 ± 2.63 in WT and from 221 ± 4.46 pmol/mg to 107 ± 5.54 in GILZ KO), the inflammatory response, TGF-β production, and α-SMA deposition in comparison to WT and GILZ KO vehicle groups.

CONCLUSION

In conclusion, the role of H4R and GILZ in relation to glucocorticoids could pave the way for innovative therapies to counteract pulmonary fibrosis.

Expression profiles of glucocorticoid-inducible proteins in human papilloma virus-related oropharyngeal squamous cell carcinoma

Introduction

Human papillomavirus virus-related oropharyngeal squamous cell carcinoma (HPV-OPSCC) comprises a significant portion of head and neck cancers. Several glucocorticoid-inducible proteins play important roles in pathogenesis of some cancers but their status and roles in HPV-OPSCC remain elusive; these include the glucocorticoid-induced leucine zipper (GILZ), Annexin-A1 and serum glucocorticoid-regulated kinase-1 (SGK-1).

Methods

We determined expression profiles of these proteins, using immunohistochemistry, in archived biopsy samples of patients diagnosed with HPV-OPSCC; samples of non-cancer oral lesions (e.g., hyperkeratosis) were used as controls.

Results

GILZ staining was primarily confined to nuclei of all tissues but, in HPV-OPSCC specimens, neoplastic cells exhibiting mitosis displayed prominent cytoplasmic GILZ expression. On the other hand, nuclear, cytoplasmic and membranous Annexin-A1 staining was observed in suprabasal cell layers of control specimens. A noted feature of the HPV-OPSCC specimens was few clusters of matured and differentiated nonbasaloid cells that showed prominent nuclear and cytoplasmic Annexin-A1 staining while the remainder of the tumor mass was devoid of staining. Cytoplasmic and nuclear staining for SGK-1 was prominent for control than PV-OPSCC specimens while staining for phosphorylated SGK-1 (pSGK-1; active) was prominent for cell membrane and cytoplasm of control specimens but HPV-OPSCC specimens showed mild and patchy nuclear and cytoplasmic staining. Semi-quantitative analysis of GILZ immunostaining indicated increased staining area but similar normalized staining for HPV-OPSCC compared to control specimens. By contrast, staining area and normalized staining were reduced for other proteins in HPV-OPSCC than control specimens.

Discussion

Our collective observations suggest differential cellular localization and expression of glucocorticoid-inducible proteins in HPV-OPSCC suggestive of different functional roles in pathogenesis of this condition.

Anti-Inflammatory Effects of Synthetic Peptides Based on Glucocorticoid-Induced Leucine Zipper (GILZ) Protein for the Treatment of Inflammatory Bowel Diseases (IBDs)

Glucocorticoids (GCs) are commonly used to treat autoimmune and inflammatory diseases, but their clinical effects and long-term use can lead to serious side effects. New drugs that can replace GCs are needed. Glucocorticoid-induced leucine zipper (GILZ) is induced by GCs and mediates many of their anti-inflammatory effects, such as inhibiting the pro-inflammatory molecule NF-κB. The GILZ C-terminal domain (PER region) is responsible for GILZ/p65NF-κB interaction and consequent inhibition of its transcriptional activity. A set of five short peptides spanning different parts of the PER region of GILZ protein was designed, and their anti-inflammatory activity was tested, both in vitro and in vivo. We tested the biological activity of GILZ peptides in human lymphocytic and monocytic cell lines to evaluate their inhibitory effect on the NF-κB-dependent expression of pro-inflammatory cytokines. Among the tested peptides, the peptide named PEP-1 demonstrated the highest efficacy in inhibiting cell activation in vitro. Subsequently, PEP-1 was further evaluated in two in vivo experimental colitis models (chemically induced by DNBS administration and spontaneous colitis induced in IL-10 knock-out (KO) mice (to assess its effectiveness in counteracting inflammation. Results show that PEP-1 reduced disease severity in both colitis models associated with reduced NF-κB pro-inflammatory activity in colon lamina propria lymphocytes. This study explored GILZ-based 'small peptides' potential efficacy in decreasing lymphocyte activation and inflammation associated with experimental inflammatory bowel diseases (IBDs). Small peptides have several advantages over the entire protein, including higher selectivity, better stability, and bioavailability profile, and are easy to synthesize and cost-effective. Thus, identifying active GILZ peptides could represent a new class of drugs for treating IBD patients.

Glucocorticoid dysfunction in children with severe malaria

Introduction

Malaria remains a widespread health problem with a huge burden. Severe or complicated malaria is highly lethal and encompasses a variety of pathological processes, including immune activation, inflammation, and dysmetabolism. Previously, we showed that adrenal hormones, in particular glucocorticoids (GCs), play critical roles to maintain disease tolerance during Plasmodium infection in mice. Here, GC responses were studied in Cameroon in children with uncomplicated malaria (UM), severe malaria (SM) and asymptomatic controls (AC).

Methods

To determine the sensitivity of leukocytes to GC signaling on a transcriptional level, we measured the ex vivo induction of glucocorticoid induced leucine zipper (GILZ) and FK506-binding protein 5 (FKBP5) by GCs in human and murine leukocytes. Targeted tracer metabolomics on peripheral blood mononuclear cells (PBMCs) was performed to detect metabolic changes induced by GCs.

Results

Total cortisol levels increased in patients with clinical malaria compared to AC and were higher in the SM versus UM group, while cortisol binding globulin levels were unchanged and adrenocorticotropic hormone (ACTH) levels were heterogeneous. Induction of both GILZ and FKBP5 by GCs was significantly reduced in patients with clinical malaria compared to AC and in malaria-infected mice compared to uninfected controls. Increased activity in the pentose phosphate pathway was found in the patients, but this was not affected by ex vivo stimulation with physiological levels of hydrocortisone. Interestingly, hydrocortisone induced increased levels of cAMP in AC, but not in clinical malaria patients.

Discussion

Altogether, this study shows that patients with SM have increased cortisol levels, but also a decreased sensitivity to GCs, which may clearly contribute to the severity of disease.

GILZ Modulates the Recruitment of Monocytes/Macrophages Endowed with a Resolving Phenotype and Favors Resolution of Escherichia coli Infection

Macrophages are important effectors of inflammation resolution that contribute to the elimination of pathogens and apoptotic cells and restoration of homeostasis. Pre-clinical studies have evidenced the anti-inflammatory and pro-resolving actions of GILZ (glucocorticoid-induced leucine zipper). Here, we evaluated the role of GILZ on the migration of mononuclear cells under nonphlogistic conditions and Escherichia coli-evoked peritonitis. TAT-GILZ (a cell-permeable GILZ-fusion protein) injection into the pleural cavity of mice induced monocyte/macrophage influx alongside increased CCL2, IL-10 and TGF-β levels. TAT-GILZ-recruited macrophages showed a regulatory phenotype, exhibiting increased expression of CD206 and YM1. During the resolving phase of E. coli-induced peritonitis, marked by an increased recruitment of mononuclear cells, lower numbers of these cells and CCL2 levels were found in the peritoneal cavity of GILZ-deficient mice (GILZ^-/-) when compared to WT. In addition, GILZ^-/- showed higher bacterial loads, lower apoptosis/efferocytosis counts and a lower number of macrophages with pro-resolving phenotypes. TAT-GILZ accelerated resolution of E. coli-evoked neutrophilic inflammation, which was associated with increased peritoneal numbers of monocytes/macrophages, enhanced apoptosis/efferocytosis counts and bacterial clearance through phagocytosis. Taken together, we provided evidence that GILZ modulates macrophage migration with a regulatory phenotype, inducing bacterial clearance and accelerating the resolution of peritonitis induced by E. coli.

Glucocorticoid Dose Dependency on Gene Expression in Vocal Fold Fibroblasts and Macrophages

OBJECTIVE

Glucocorticoids (GCs) modulate multiple cellular activities including inflammatory and fibrotic responses. Outcomes of GC treatment for laryngeal disease vary, affording opportunity to optimize treatment. In the current study, three clinically employed GCs were evaluated to identify optimal in vitro concentrations at which GCs mediate favorable anti-inflammatory and fibrotic effects in multiple cell types. We hypothesize a therapeutic window will emerge as a foundation for optimized therapeutic strategies for patients with laryngeal disease.

STUDY DESIGN

In vitro.

METHODS

Human vocal fold fibroblasts and human macrophages derived from THP-1 monocytes were treated with 0.03-1000 nM dexamethasone, 0.3-10,000 nM methylprednisolone, and 0.3-10,000 nM triamcinolone in combination with interferon-γ, tumor necrosis factor-α, or interleukin-4. Real-time polymerase chain reaction was performed to analyze inflammatory (CXCL10, CXCl11, PTGS2, TNF, IL1B) and fibrotic (CCN2, LOX, TGM2) genes, and TSC22D3, a target gene of GC signaling. EC50 and IC50 to alter inflammatory and fibrotic gene expression was calculated.

RESULTS

Interferon-γ and tumor necrosis factor-α increased inflammatory gene expression in both cell types; this response was reduced by GCs. Interleukin-4 increased LOX and TGM2 expression in macrophages; this response was also reduced by GCs. GCs induced TSC22D3 and CCN2 expression independent of cytokine treatment. EC50 for each GC to upregulate CCN2 was higher than the IC50 to downregulate other genes.

CONCLUSION

Lower concentrations of GCs repressed inflammatory gene expression and only moderately induced genes involved in fibrosis. These data warrant consideration as a foundation for optimized clinical care paradigms to reduce inflammation and mitigate fibrosis.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:1169-1175, 2023.

Elucidation of the mechanisms underlying tumor aggravation by the activation of stress-related neurons in the paraventricular nucleus of the hypothalamus

A growing body of evidence suggests that excess stress could aggravate tumor progression. The paraventricular nucleus (PVN) of the hypothalamus plays an important role in the adaptation to stress because the hypothalamic-pituitary-adrenal (HPA) axis can be activated by inducing the release of corticotropin-releasing hormone (CRH) from the PVN. In this study, we used pharmacogenetic techniques to investigate whether concomitant activation of CRH^PVN neurons could directly contribute to tumor progression. Tumor growth was significantly promoted by repeated activation of CRH^PVN neurons, which was followed by an increase in the plasma levels of corticosterone. Consistent with these results, chronic administration of glucocorticoids induced tumor progression. Under the concomitant activation of CRH^PVN neurons, the number of cytotoxic CD8⁺ T cells in the tumor microenvironment was dramatically decreased, and the mRNA expression levels of hypoxia inducible factor 1 subunit α (HIF1α), glucocorticoid receptor (GR) and Tsc22d3 were upregulated in inhibitory lymphocytes, tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). Furthermore, the mRNA levels of various kinds of driver molecules related to tumor progression and tumor metastasis were prominently elevated in cancer cells by concomitant activation of CRH^PVN neurons. These findings suggest that repeated activation of the PVN-CRHergic system may aggravate tumor growth through a central-peripheral-associated tumor immune system.

Association of GILZ with MUC2, TLR2, and TLR4 in Inflammatory Bowel Disease

Ulcerative colitis (UC) and Crohn's Disease (CD) are chronic relapsing inflammatory diseases that are caused by genetic, environmental, and immune factors. Treatment strategies are currently based on symptomatic control by immunosuppression. The glucocorticoid-induced leucine zipper (GILZ), a mediator of several effects of glucocorticoids, was recently found to be secreted by goblet cells and play a role in inflammatory bowel disease (IBD). This study investigates which genes GILZ is associated with in its role in intestinal barrier functions. We examined datasets from the Gene Expression Omnibus (GEO) and ArrayExpress profiles of the gut of healthy subjects (HSs), as well as UC and CD patients. The human colonic epithelial HT29 cell line was used for in vitro validation experiments. GILZ was significantly correlated with MUC2, TLR2, and TLR4. In particular, an inverse correlation was found between the GILZ and MUC2 in HS and patients with IBD, mostly in those with an active disease. Further, direct pairwise correlations for GILZ/TLR2 and GILZ/TLR4 were found in HSs and UC patients, but not in CD patients. Overall, our results reveal the crosstalk at the transcription level between the GILZ, MUC2, and TLRs in the mucosal barrier through common pathways, and they open up new perspectives in terms of mucosal healing in IBD patients.

Glucocorticoids and COVID-19

Coronavirus Disease 19 (COVID-19) is associated with high morbidity and mortality rates globally, representing the greatest health and economic challenge today. Several drugs are currently approved for the treatment of COVID-19. Among these, glucocorticoids (GCs) have received particular attention due to their anti-inflammatory and immunosuppressive effects. In fact, GC are widely used in current clinical practice to treat inflammatory, allergic and autoimmune diseases. Major mechanisms of GC action include inhibition of innate and adaptive immune activity. In particular, an important role is played by the inhibition of pro-inflammatory cytokines and chemokines, and the induction of proteins with anti-inflammatory activity. Overall, as indicated by various national and international regulatory agencies, GCs are recommended for the treatment of COVID-19 in patients requiring oxygen therapy, with or without mechanical ventilation. Regarding the use of GCs for the COVID-19 treatment of non-hospitalized patients at an early stage of the disease, many controversial studies have been reported and regulatory agencies have not recommended their use. The decision to start GC therapy should be based not only on the severity of COVID-19 disease, but also on careful considerations of the benefit/risk profile in individual patients, including monitoring of adverse events. In this review we summarize the effects of GCs on the major cellular and molecular components of the inflammatory/immune system, the benefits and the adverse common reactions in the treatment of inflammatory/autoimmune diseases, as well as in the management of COVID-19.

Circadian Clock, Glucocorticoids and NF-κB Signaling in Neuroinflammation- Implicating Glucocorticoid Induced Leucine Zipper as a Molecular Link

Inflammation including neuroinflammation is considered a protective response and is directed to repair, regenerate, and restore damaged tissues in the central nervous system. Persistent inflammation due to chronic stress, age related accrual of free radicals, subclinical infections or other factors lead to reduced survival and increased neuronal death. Circadian abnormalities secondary to altered sleep/wake cycles is one of the earliest signs of neurodegenerative diseases. Brain specific or global deficiency of core circadian trans-activator brain and muscle ARNT (Arylhydrocarbon Receptor Nuclear Translocator)-like protein 1 (BMAL1) or that of the transrepressor REV-ERBα, impaired neural function and cognitive performance in rodents. Consistently, transcripts of inflammatory cytokines and host immune responses have been shown to exhibit diurnal variation, in parallel with the disruption of the circadian rhythm. Glucocorticoids that exhibit both a circadian rhythm similar to that of the core clock transactivator BMAL1 and tissue specific ultradian rhythm are critical in the control of neuroinflammation and re-establishment of homeostasis. It is widely accepted that the glucocorticoids suppress nuclear factor-kappa B (NF-κB) mediated transactivation and suppress inflammation. Recent mechanistic elucidations suggest that the core clock components also modulate NF-κB mediated transactivation in the brain and peripheral tissues. In this review we discuss evidence for interactions between the circadian clock components, glucocorticoids and NF-κB signaling responses in the brain and propose glucocorticoid induced leucine zipper (GILZ) encoded by Tsc22d3, as a molecular link that connect all three pathways in the maintenance of CNS homeostasis as well as in the pathogenesis of neuroinflammation-neurodegeneration.

The novel role of glucocorticoid-induced leucine zipper as a marker of mucosal healing in inflammatory bowel diseases

Glucocorticoid-induced leucin zipper (GILZ) mediates the effects of glucocorticoids in immune cells, but little is known about its role in both the gastro-intestinal (GI) mucosa and inflammatory bowel diseases (IBD) in humans. To investigate the GILZ protein expression profile in the GI tract, mucosal biopsies from 80 patients were retrospectively enrolled in this study and subdivided into three groups: 1) patients without clinical-endoscopic and histological evidence of IBD; 2) IBD patients; 3) patients with chronic atrophic gastritis (CAG) and Barrett esophagus (BE), both characterized by intestinal metaplasia (IM). GILZ expression was assessed by immunohistochemical and immunofluorescence methods. Our results showed that GILZ protein was strongly expressed in the secretory cells in healthy mucosa. GILZ expression was reduced in goblet cells in active disease, whereas it was restored in quiescent diseases. Conversely, entero-endocrine cells were not involved in such inflammation-driven dynamics, as GILZ expression remained detectable in active disease. Moreover, GILZ was expressed in IM, but was limited to CAG, and was not detected in BE. In summary, GILZ acts as a secretory protein in the GI mucosa in healthy, hyperplastic and metaplastic conditions. Its secretion by goblet cells is mostly affected by neutrophils mucosal infiltration and seems to be directly related to active mucosal inflammation in IBD. Overall, our findings suggest that GILZ is a suitable molecule to be considered as a histological marker of mucosal healing.