Prolonged hypernutrition impairs TREM2-dependent efferocytosis to license chronic liver inflammation and NASH development.

Obesity-induced chronic liver inflammation is a hallmark of nonalcoholic steatohepatitis (NASH)-an aggressive form of nonalcoholic fatty liver disease. However, it remains unclear how such a low-grade, yet persistent, inflammation is sustained in the liver. Here, we show that the macrophage phagocytic receptor TREM2, induced by hepatocyte-derived sphingosine-1-phosphate, was required for efferocytosis of lipid-laden apoptotic hepatocytes and thereby maintained liver immune homeostasis. However, prolonged hypernutrition led to the production of proinflammatory cytokines TNF and IL-1ß in the liver to induce TREM2 shedding through ADAM17-dependent proteolytic cleavage. Loss of TREM2 resulted in aberrant accumulation of dying hepatocytes, thereby further augmenting proinflammatory cytokine production. This ultimately precipitated a vicious cycle that licensed chronic inflammation to drive simple steatosis transition to NASH. Therefore, impaired macrophage efferocytosis is a previously unrecognized key pathogenic event that enables chronic liver inflammation in obesity. Blocking TREM2 cleavage to restore efferocytosis may represent an effective strategy to treat NASH.

Cleavage of protein kinase c δ by caspase-3 mediates proinflammatory cytokine-induced apoptosis in pancreatic islets.

In type 1 diabetes (T1D), autoreactive immune cells infiltrate the pancreas and secrete proinflammatory cytokines that initiate cell death in insulin producing islet ß-cells. Protein kinase C δ (PKCδ) plays a role in mediating cytokine-induced ß-cell death; however, the exact mechanisms are not well understood. To address this, we used an inducible ß-cell specific PKCδ KO mouse as well as a small peptide inhibitor of PKCδ. We identified a role for PKCδ in mediating cytokine-induced ß-cell death and have shown that inhibiting PKCδ protects pancreatic ß-cells from cytokine-induced apoptosis in both mouse and human islets. We determined that cytokines induced nuclear translocation and activity of PKCδ and that caspase-3 cleavage of PKCδ may be required for cytokine-mediated islet apoptosis. Further, cytokine activated PKCδ increases activity both of proapoptotic Bax with acute treatment and C-Jun N-terminal kinase with prolonged treatment. Overall, our results suggest that PKCδ mediates cytokine-induced apoptosis via nuclear translocation, cleavage by caspase-3, and upregulation of proapoptotic signaling in pancreatic ß-cells. Combined with the protective effects of PKCδ inhibition with δV1-1, the results of this study will aid in the development of novel therapies to prevent or delay ß-cell death and preserve ß-cell function in T1D.

Outer membrane protein 25 of Brucella suppresses TLR-mediated expression of proinflammatory cytokines through degradation of TLRs and adaptor proteins.

Toll-like receptors (TLRs) are essential components of innate immunity that serves as the first line of defense against the invaded microorganisms. However, successful infectious pathogens subvert TLR signaling to suppress the activation of innate and adaptive responses. Brucella species are infectious intracellular bacterial pathogens causing the worldwide zoonotic disease, brucellosis, that impacts economic growth of many countries. Brucella species are considered as stealthy bacterial pathogens as they efficiently evade or suppress host innate and adaptive immune responses for their chronic persistence. However, the bacterial effectors and their host targets for modulating the immune responses remain obscure. Brucella encodes various outer membrane proteins (Omps) that facilitate their invasion, intracellular replication, and immunomodulation. Outer membrane protein 25 (Omp25) of Brucella plays an important role in the immune modulation through suppression of proinflammatory cytokines. However, the mechanism and the signaling pathways that are targeted by Omp25 to attenuate the production of proinflammatory cytokines remain obscure. Here, we report that Omp25 and its variants, viz. Omp25b, Omp25c, and Omp25d, suppress production of proinflammatory cytokines that are mediated by various TLRs. Furthermore, we demonstrate that Omp25 and its variants promote enhanced ubiquitination and degradation of TLRs and their adaptor proteins to attenuate the expression of proinflammatory cytokines. Targeting multiple TLRs and adaptor proteins enables Omp25 to effectively suppress the expression of proinflammatory cytokines that are induced by diverse pathogen-associated molecular patterns. This can contribute to the defective adaptive immune response and the chronic persistence of Brucella in the host.

Phytotherapy-Induced Hepatocytotoxicity: A Case Report.

Herbal and complementary medicine are frequently integrated with conventional medicine. We aim to report a case of severe herbal-induced liver injury (HILI) due to chronic use of green tea and protein shake. We present both clinical and laboratory evidence implicating mitochondrial toxicity and an immune response leading to a hypersensitivity reaction to the products. We have recently treated a 39-year-old man with hepatotoxicity resulting from a combination of a green tea-containing powder and a branched-chain amino acid supplement that was commenced 2 months previously. The hepatotoxicity resolved by stopping the consumption of these products and no other cause was detected. We decided to perform a lymphocyte toxicity assay (LTA) to determine if there was laboratory support for this diagnosis. LTA (% toxicity) represents the response of the mitochondria to toxic injury. To determine the role of the proinflammatory and anti-inflammatory cytokines and chemokines in the patient's reaction, we measured the level of cytokines and chemokine in the media of growing cells, exposed to each product or to a combination of products. The increased cytokines and chemokines are presented as the x-fold elevations from the upper limit of normal (ULN) for matrix metalloproteinase (MMP) (pg/mL × 1.5 ULN) and interleukin (IL)-1ß (pg/mL × 1.8 ULN). Higher elevations were found for interferon (IFN)-ß, IFN-γ, IL-8, IL 13, IL-15 (pg/mL × 2 ULN), regulated upon activation, normal T cell expressed and presumably secreted (RANTES) (pg/mL × 2 ULN), and nuclear factor (NFκB) (pg/mL × 3 ULN). The highest increases were for vascular endothelial factor (VEGF) (pg/mL × 10 ULN), tumor necrosis factor (TNF)-α, and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) (pg/mL × 13 ULN). An examination of cellular markers showed the difference between programmed cell death (apoptosis) and cell death due to necrosis. In our case, cytokeratin-ccK18 (M-30) U/L was within the normal limits, suggesting that apoptosis was normal, while ccK8(M65) U/L was elevated at 1.5 × ULN. This result implies that upon the treatment of the patient's lymphocytes with the products, the mechanism of toxicity is necrosis. In susceptible individuals, the combination of protein and herbal tea produces mitochondrial toxicity and a strong T-lymphocyte-1 response, leading to HILI. There is a need of international reporting of adverse drug reactions by clinicians, laboratories, and pharmaceutical manufacturers to drug regulatory authorities. This requires internationally accepted standard definitions of reactions, as well as criteria for assessment.

Changes in neuroinflammatory markers and microglial density in the hippocampus and prefrontal cortex of the C58/J mouse model of autism.

Autism spectrum disorder (ASD) is a diverse group of neurodevelopmental conditions with complex origins. Individuals with ASD present various neurobiological abnormalities, including an altered immune response in the central nervous system and other tissues. Animal models like the C58/J inbred mouse strain are used to study biological characteristics of ASD. This strain is considered an idiopathic autism model because of its demonstrated reduced social preference and repetitive behaviours. Notably, C58/J mice exhibit alterations in dendritic arbour complexity, density and dendritic spines maturation in the hippocampus and prefrontal cortex (PFC), but inflammatory-related changes have not been explored in these mice. In this study, we investigated proinflammatory markers in the hippocampus and PFC of adult male C58/J mice. We discovered elevated levels of interferon gamma (IFN-γ) and monocyte chemoattractant protein 1 (MCP-1) in the hippocampus, suggesting increased inflammation, alongside a reduction in the anti-inflammatory enzyme arginase 1 (ARG1). Conversely, the PFC displayed reduced levels of TNF-α and MCP-1. Microglial analysis revealed higher levels of transmembrane protein 119 (TMEM119) and increased microglial density in a region-specific manner of the autistic-like mice, particularly in the PFC and hippocampus. Additionally, an augmented expression of the fractalkine receptor CX3CR1 was observed in the hippocampus and PFC of C58/J mice. Microglial morphological analysis shows no evident changes in the hippocampus of mice with autistic-like behaviours versus wild-type strain. These region-specific changes can contribute to modulate processes like inflammation or synaptic pruning in the C58/J mouse model of idiopathic autism.

Downregulation of nuclear receptor-binding SET domain protein 1 induces proinflammatory cytokine expression via mitogen-activated protein kinase pathways in U87MG cells.

Haploinsufficiency of the nuclear receptor binding SET domain-containing protein 1 gene (NSD1) leads to a neurodevelopmental disorder known as Sotos syndrome (SOTOS). This study investigated the effects of NSD1 knockdown in glial cells. U87MG glioma cells were transfected with siRNA targeting NSD1, which resulted in morphological changes characteristic of activated astrocytes. These activated phenotypes were accompanied by specific activation of mitogen-activated protein kinase (MAPK) signaling pathways, particularly those mediated by p38 MAPK and c-Jun N-terminal kinase (JNK). Transcriptome analysis showed increased expression of proinflammatory cytokine genes, particularly interleukin (IL)-1α, IL-1ß, and IL-6, following NSD1 knockdown. Treatment with MAPK inhibitors significantly reduced the cytokine induction caused by NSD1 knockdown, with the p38 MAPK inhibitor being more effective than the JNK inhibitor. These findings provide new insights into the role of NSD1 loss in neurological dysfunctions associated with SOTOS.

The correlation of GluR3B antibody with T lymphocyte subsets and inflammatory factors and their role in the progression of epilepsy.

OBJECTIVE: To investigate changes in proportions of peripheral blood lymphocyte subsets, the correlation between the lymphocyte subsets and cytokine levels in patients with GluR3B antibody-positive epilepsy, analyze the role of GluR3B antibodies and cytokines in the progression of epilepsy. In addition, the immunotherapeutic effect in patients with GluR3B antibody-positive epilepsy will be evaluated. METHODS: Patients with epilepsy hospitalized in the Department of Neurology of the affiliated Hospital of Xuzhou Medical University from December 2016 to May 2023 were recruited. GluR3B antibody levels were measured by enzyme-linked immunosorbent assay (ELISA). Lymphocyte subset proportions were determined using flow cytometry, and serum concentrations of 12 cytokines were measured using cytometric beads array. Differences in T lymphocyte subsets and inflammatory factors were analysed between GluR3B antibody positive and negative patients. Structural equation modeling (SEM) was used to analyse the role of GluR3B antibodies and inflammatory factors in drug-resistant epilepsy (DRE). Finally, the therapeutic effect of immunotherapy on epilepsy patients with GluR3B antibodies was assessed. RESULTS: In this study, sixty-four cases of DRE, sixty-six cases of drug-naïve epilepsy (DNE), and forty-one cases of drug-responsive epilepsy were recruited. (1) DRE patients with positive GluR3B antibody were characterized by a significant increase in the proportion of cluster of differentiation (CD)4+ T lymphocytes, a decrease in CD8+ T lymphocytes, and an increase of CD4+/CD8+ ratio. Similar alterations in T lymphocyte subsets were observed in GluR3B antibody-positive patients with DNE. GluR3B antibody levels correlated positively with CD4+ T lymphocytes (r = 0.23) and negatively with CD8+ T lymphocytes (r=-0.18). (2) In patients with DRE, the serum concentrations of interleukin-1ß (IL-1ß), IL-8, and interferon-gamma (IFN-γ) were significantly higher in those with positive GluR3B antibody compared to those with negative GluR3B antibody. Serum IL-1ß levels were also higher in GluR3B antibody-positive DNE patients compared to antibody-negative DNE patients. In drug-responsive epilepsy patients with GluR3B antibody-positive, both serum IL-1ß and IFN-γ levels were higher than those with GluR3B antibody-negative. Moreover, the concentrations of serum GluR3B antibody were positively correlated with the levels of IL-1ß, IL-8, and IFN-γ. (3) SEM analysis indicated that GluR3B antibody may be a direct risk factor for DRE (direct effect = 4.479, 95%CI 0.409-8.503), or may be involved in DRE progression through affecting IFN-γ and IL-8 levels (total indirect effect = 5.101, 95%CI 1.756-8.818). (4) Immunotherapy significantly decreased seizure frequency and serum GluR3B antibody levels, and the seizure frequency was positively correlated with the levels of GluR3B antibody levels in patients receiving immunotherapy. CONCLUSIONS: This study demonstrates that GluR3B antibody may influence the progression of epilepsy through altering the proportion of CD4+ and CD8+ lymphocyte subsets and increasing proinflammatory cytokines. The seizure suppression of immunotherapy is associated with the decrease of GluR3B antibody levels. Thus, the present study contributes to a better understanding of the immunoregulatory mechanisms of autoimmune-associated epilepsy and provides a potential target for DRE.

Evaluation of some proinflammatory cytokines and biochemical parameters in pre and postmenopausal breast cancer women.

The study was planned to evaluate the differences in certain proinflammatory cytokines(IL-6, TNF-α) with CRP and biochemical parameters (E2, D3, LDH, GGT, TSB, Ca, Ph, uric acid), between women with pre- and postmenopausal breast cancer and seemingly healthy women in Iraqi women as controls; at medical city in teaching Oncology hospital,70 breast cancer patients women their ages ranged (47.51 ± 1.18) and 20 healthy women with age (44.45 ± 2.66) begun from September (2020) to February (2021). The aims of this study to investigate the evaluation of chemotherapy effects especially doxorubicin and cyclophosphamide only use in this study in pre and postmenopausal breast cancer women on proinflammatory cytokines(IL-6, TNF-α) with CRP and on biochemical parameters(E2, D3, LDH, GGT, TSB, Ca, Ph, uric acid) in pre and postmenapausal breast cancer women. The patients were divided into five groups and each group contains 14 patients women with breast cancer during pre and postmenopausal periods. The control groups were divided into 10 pre and 10 postmenopausal women(Fig. 1). The results of proinflammatory cytokines of and biochemical parameters in premenopausal groups were as the levels of IL-6 (pg/ml),TNF-α(pg/ml) and CRP (ng/ml) showed significant increase differences (P < 0.01)among breast cancer treated (BCT) groups in comparison with control groups,While the Liver enzymes GGT,LDH and TSB showed highly significant increase (P < 0.01) in BCT groups, Estrogen levels (pg/ml) and D3(ng/ml) increased significantly (P < 0.01)among BCT groups. Blood serum calcium and phosphorus with uric acid levels (mg/dl) showed significant difference (P < 0.01); While the result in postmenopausal of IL-6(pg/ml), TNF-α (pg/ml) and CRP (ng/ml) showed highly significant differences (P < 0.01)among BCT groups.While GGT(IU/L), LDH(IU/L) and TSB (mg/dl) enzymes were increased significantly (p < 0.01), Estrogen (pg/ml) and D3(ng/ml) levels showed significant increase (P < 0.01) among BCT groups.Blood calcium and phosphorus showed significant increase (P < 0.01) while uric acid was non-significant increase (P > 0.05).

The roles of SFKs in the regulation of proinflammatory cytokines and NLRP3 in familial mediterranean fever patients.

Familial Mediterranean Fever (FMF) is caused by mutations in pyrin, a protein produced in innate immune cells that regulates the development of interleukin (IL)-1ß by interacting with caspase-1 and other components of inflammasomes. Although overexpression of proinflammatory cytokines have been observed in FMF patients, no studies have been conducted on the role of Src family kinases (SFKs). The purpose of this study was to examine the impact of SFKs on the modulation of IL-1ß, IL-6, IL-8, TNF-α, and NLRP3 inflammasome in patients with FMF. The study included 20 FMF patients and 20 controls. Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifugation. Protein expression levels of SFKs members were measured by western blot. The effect of lipopolysaccharide-induced (LPS) activation and PP2- induced inhibition of SFKs on NLRP3 and IL-1ß, IL 6, IL-8, TNF-α were examined by western blot and flow cytometry respectively. Patients with FMF have considerably greater levels of Lck expression. In addition, patients had a substantially greater basal level of NLRP3 than the control group (*p = 0.016). Most importantly, the levels of IL-1 ß were elevated with LPS stimulation and reduced with PP2 inhibition in FMF patients. These results suggest that SFKs are effective in regulation of IL-1 ß in FMF patients.

Mucosal-associated invariant T cells modulate innate immune cells and inhibit colon cancer growth.

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that can be activated by microbial antigens and cytokines and are abundant in mucosal tissues including the colon. MAIT cells have cytotoxic and pro-inflammatory functions and have potentials for use as adoptive cell therapy. However, studies into their anti-cancer activity, including their role in colon cancer, are limited. Using an animal model of colon cancer, we showed that peritumoral injection of in vivo-expanded MAIT cells into RAG1-/- mice with MC38-derived tumours inhibits tumour growth compared to control. Multiplex cytokine analyses showed that tumours from the MAIT cell-treated group have higher expression of markers for eosinophil-activating cytokines, suggesting a potential association between eosinophil recruitment and tumour inhibition. In a human peripheral leukocyte co-culture model, we showed that leukocytes stimulated with MAIT ligand showed an increase in eotaxin-1 production and activation of eosinophils, associated with increased cancer cell killing. In conclusion, we showed that MAIT cells have a protective role in a murine colon cancer model, associated with modulation of the immune response to cancer, potentially involving eosinophil-associated mechanisms. Our results highlight the potential of MAIT cells for non-donor restricted colon cancer immunotherapy.