A novel RIPK1 inhibitor reduces GVHD in mice via a nonimmunosuppressive mechanism that restores intestinal homeostasis.

Intestinal epithelial cells (IECs) are implicated in the propagation of T-cell-mediated inflammatory diseases, including graft-versus-host disease (GVHD), but the underlying mechanism remains poorly defined. Here, we report that IECs require receptor-interacting protein kinase-3 (RIPK3) to drive both gastrointestinal (GI) tract and systemic GVHD after allogeneic hematopoietic stem cell transplantation. Selectively inhibiting RIPK3 in IECs markedly reduces GVHD in murine intestine and liver. IEC RIPK3 cooperates with RIPK1 to trigger mixed lineage kinase domain-like protein-independent production of T-cell-recruiting chemokines and major histocompatibility complex (MHC) class II molecules, which amplify and sustain alloreactive T-cell responses. Alloreactive T-cell-produced interferon gamma enhances this RIPK1/RIPK3 action in IECs through a JAK/STAT1-dependent mechanism, creating a feed-forward inflammatory cascade. RIPK1/RIPK3 forms a complex with JAK1 to promote STAT1 activation in IECs. The RIPK1/RIPK3-mediated inflammatory cascade of alloreactive T-cell responses results in intestinal tissue damage, converting the local inflammation into a systemic syndrome. Human patients with severe GVHD showed highly activated RIPK1 in the colon epithelium. Finally, we discover a selective and potent RIPK1 inhibitor (Zharp1-211) that significantly reduces JAK/STAT1-mediated expression of chemokines and MHC class II molecules in IECs, restores intestinal homeostasis, and arrests GVHD without compromising the graft-versus-leukemia (GVL) effect. Thus, targeting RIPK1/RIPK3 in IECs represents an effective nonimmunosuppressive strategy for GVHD treatment and potentially for other diseases involving GI tract inflammation.

Melatonin alleviates titanium nanoparticles induced osteolysis via activation of butyrate/GPR109A signaling pathway.

BACKGROUND: Inflammatory osteolysis after total joint replacement (TJR) may cause implant failure, periprosthetic fractures, and be a severe threat to global public health. Our previous studies demonstrated that melatonin had a therapeutic effect on wear-particles induced osteolysis. Gut microbiota is closely related to bone homeostasis, and has been proven to be affected by melatonin. However, whether melatonin could play its anti-osteolysis effects through reprogramming gut microbiota remains elusive. RESULTS: Here, we demonstrated that melatonin could alleviate Ti-particles induced osteolysis, while this therapeutic effect was blocked by antibiotic cocktail treatment. Interestingly, transplantation of fecal microbiota from mice treated with melatonin reappeared the same beneficial effect. Analysis of the 16S rRNA revealed that melatonin could reverse dysbacteriosis triggered by osteolysis, and elevate the relative abundance of some short chain fatty acid (SCFA) producing bacteria. Moreover, butyrate was enriched by exogenous melatonin administration, while acetate and propionate did not show an evident difference. This was consistent with the results of the metagenomic approach (PICRUSt2) analysis, which revealed a general increase in the synthetic enzymes of butyrate. More importantly, direct supplementation of butyrate could also recapitulate the anti-osteolysis effect of melatonin. Further analysis identified that butyrate alleviated osteolysis via activating its receptor GPR109A, and thus to suppress the activation of NLRP3 inflammasome triggered by Ti-particles. CONCLUSIONS: Taken together, our results suggested that the benefits of melatonin mainly depend on the ability of modulating gut microbiota and regulating butyrate production.

A meta-analysis of dietary carbohydrate intake and inflammatory bowel disease risk: evidence from 15 epidemiology studies.

BACKGROUND AND PURPOSE: epidemiological studies that assess the association of dietary total carbohydrate intake and inflammatory bowel disease risk (IBD) have yielded controversial results. Therefore, this study of various epidemiological studies was conducted in order to explore this relationship. METHODS: a systematic literature search of the PubMed, Embase, Web of Science and Medline databases was performed up to September 2017. Cohort, case-control or cross-sectional design studies were included that reported the association of dietary carbohydrate intake and IBD risk. Summary odds ratio (OR) and the corresponding 95% CI were calculated using the random effects model. RESULTS: a total of eight articles with 15 individual studies that included 1,361 cases were eligible according to the inclusion criteria. Dietary carbohydrate intake had a non-significant relationship with the risk of IBD (OR = 1.091, 95% CI = 0.817-1.455, I2 = 31.6%, pfor heterogeneity = 0.116). The pooled OR and 95% CI for ulcerative colitis (UC) and Crohn's disease (CD) with regard to dietary carbohydrate intake was 1.167 (0.777-1.752) and 1.010 (0.630-1.618), respectively. These associations were also non-significant in both European and Asia populations. CONCLUSIONS: a higher dietary total carbohydrate intake had a non-significant relationship with IBD risk. Further studies with large populations are needed to verify this relationship.

A novel splice donor mutation in DCLRE1C caused atypical severe combined immunodeficiency in a patient with colon lymphoma: case report and literature review.

Introduction: Hypomorphic mutations of DCLRE1C cause an atypical severe combined immunodeficiency (SCID), and Epstein-Barr virus (EBV)-related colon lymphoma is a rare complication. Case presentation: A teenage boy presented with colon EBV-related colon lymphoma, plantar warts, and a history of recurrent pneumonia. His peripheral blood lymphocyte count and serum level of immunoglobulin (Ig) G were normal, but he exhibited a T+B-NK+ immunophenotype. Genetic analysis by whole exome sequencing revealed compound heterozygous mutations of DCLRE1C (NM_001033855.3), including a novel paternal splicing donor mutation (c.109 + 2T>C) in intron 1, and a maternal c.1147C>T (p.R383X) nonsense mutation in exon 13. Based on his clinical features and genetic results, the diagnosis of atypical SCID with colon lymphoma was established. Our review shows that seven patients, including our patient, have been reported to develop lymphoma, all with hypomorphic DCLRE1C mutations. Among these cases, six had EBV-related B-cell lineage lymphoma, and one had Hodgkin lymphoma with EBV reactivation. Unfortunately, all of the patients died. Conclusion: Recognizing the radiosensitivity of the disease is critical for the prognosis. Hematopoietic stem cell transplantation before being infected with EBV is an optimal treatment.

Corrigendum: Efficacy and Safety of Shenqu Xiaoshi Oral Liquid Compared With Domperidone Syrup in Children With Functional Dyspepsia.

[This corrects the article DOI: 10.3389/fphar.2022.831912.].

Efficacy and Safety of Shenqu Xiaoshi Oral Liquid Compared With Domperidone Syrup in Children With Functional Dyspepsia.

Background: Treatment of functional dyspepsia (FD) in children is generally symptomatic and unsatisfactory. Traditional Chinese medicines, such as Shenqu Xiaoshi Oral Liquid (SXOL), have been recommended to alleviate dyspeptic symptoms. However, evidence of their safety and efficacy remains limited to date. AIM: To assess whether 2 weeks of therapy with SXOL was non-inferior to domperidone syrup in children with FD. Methods: In this randomized, double-blind, double-simulated, non-inferiority, multi-center clinical trial, we recruited children (3-14 years) with FD according to the Rome IV criteria from 17 tertiary medical centers across China. Patients were randomly allocated (1:1) to receive SXOL or domperidone syrup for 2 weeks. We compared the participants' clinical scores from both groups based on the severity and frequency of dyspepsia symptoms according to Rome IV criteria (0, 1, 2, and 4 weeks after randomization). The primary endpoint was the total response rate, which was defined as the proportion of patients with a decrease of 30% or more in the FD symptoms clinical score from baseline, at the end of the 2-weeks treatment. A non-inferiority margin of -10% was set. Secondary endpoints and adverse events were assessed. This trial is registered with www.Chictr.org.cn, number ChiCTR1900022654. Results: Between February 2019 and March 2021, a total of 373 patients were assessed for eligibility, and 356 patients were enrolled and randomized. The clinical response rate at week two was similar for SXOL [118 (83.10%) of 142] and domperidone [128 (81.01%) of 158]; difference 2.09; 95% CI -6.74 to 10.71, thereby establishing non-inferiority. The total FD symptom scores were significantly improved in the two groups at 1-, 2-, and 4-weeks follow-up periods (p < 0.005). The decrease in symptom score compared with the baseline were similar between these two groups. Over the total study period, 10 patients experienced at least one treatment-related adverse event [six (3.37%)] in the SXOL group, four [(2.25%) in the domperidone group], although no serious adverse event was noted. Conclusion: Treatment with SXOL effectively improves dyspeptic symptoms and is well tolerated. In addition, it is not inferior to domperidone syrup and leads to sustained improvement in Chinese children with FD.