Mouse Model Of Sensitization Research Articles

Beta Spike-Presenting SARS-CoV-2 Virus-like Particle Vaccine Confers Broad Protection against Other VOCs in Mice.

Virus-like particles (VLPs) are non-infectious and serve as promising vaccine platforms because they mimic the membrane-embedded conformations of fusion glycoproteins on native viruses. Here, we employed SARS-CoV-2 VLPs (SMEN) presenting ancestral, Beta, or Omicron spikes to identify the variant spike that elicits potent and cross-protective immune responses in the highly sensitive K18-hACE2 challenge mouse model. A combined intranasal and intramuscular SMEN vaccine regimen generated the most effective immune responses to significantly reduce disease burden. Protection was primarily mediated by antibodies, with minor but distinct contributions from T cells in reducing virus spread and inflammation. Immunization with SMEN carrying ancestral spike resulted in 100, 75, or 0% protection against ancestral, Delta, or Beta variant-induced mortality, respectively. However, SMEN with an Omicron spike provided only limited protection against ancestral (50%), Delta (0%), and Beta (25%) challenges. By contrast, SMEN with Beta spikes offered 100% protection against the variants used in this study. Thus, the Beta variant not only overcame the immunity produced by other variants, but the Beta spike also elicited diverse and effective humoral immune responses. Our findings suggest that leveraging the Beta variant spike protein can enhance SARS-CoV-2 immunity, potentially leading to a more comprehensive vaccine against emerging variants.

Melatonin Regulates Neuronal Synaptic Plasticity in the Supramammillary Nucleus and Attenuates Methamphetamine-Induced Conditioned Place Preference and Sensitization in Mice.

Methamphetamine (METH) is an addictive drug that threatens human health. The supramammillary nucleus (SuM) and its neural circuits play key roles in the regulation of spatial memory retrieval, and hippocampal contextual or social memory. Melatonin (MLT), a pineal hormone, can regulate hypothalamic-neurohypophysial activity. Our previous study showed that MLT attenuates METH-induced locomotor sensitization. However, whether MLT regulates SuM function and participates in METH-induced contextual memory retrieval remains unclear. Using a mouse model of METH-conditioned place preference (CPP) and sensitization, we found that METH activated c-Fos expression and elevated calcium (Ca²⁺) levels in SuM neurons. Chemogenetic inhibition of SuM attenuates CPP and sensitization. Pretreatment with MLT decreased c-Fos expression and Ca2+ levels in the SuM and reversed METH-induced addictive behavior, effects that were blocked with the selective MT2 receptors antagonist 4P-PDOT and the MT1 receptors antagonist S26131. Furthermore, MLT reduced SuM synaptic plasticity, glutamate (Glu) release, and neuronal oscillations caused by METH, which were blocked by 4P-PDOT. In conclusion, our data revealed that MLT regulates neuronal synaptic plasticity in the SuM, likely through the MLT receptors (MTs), and plays a role in modulating METH-addictive behavior.

Single-cell RNA sequencing revealed the role of the Th17 pathway in the development of anti- human leukocyte antigen antibodies in a highly sensitized mouse model.

The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse. For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.1)1Enge/J mouse (allogeneic mouse, ALLO). For syngeneic control (SYN), skin grafts were transferred from C57BL/6 to C57BL/6. We performed single-cell RNA-sequencing analysis on splenocytes isolated from ALLO and SYN and compared the gene expression between them. We generated 9,190 and 8,890 single-cell transcriptomes from ALLO and SYN, respectively. Five major cell types (B cells, T cells, natural killer cells, macrophages, and neutrophils) and their transcriptome data were annotated according to the representative differentially expressed genes of each cell cluster. The percentage of B cells was higher in ALLO than it was in SYN. Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the highly expressed genes in the B cells from ALLO were mainly associated with antigen processing and presentation pathways, allograft rejection, and the Th17 cell differentiation pathway. Upregulated genes in the T cells of ALLO were involved in the interleukin (IL)-17 signaling pathway. The ratio of Th17 cluster and Treg cluster was increased in the ALLO. On flow cytometry, the percentage of Th17 (IL-17+/CD4+ T) cells was higher and regulatory T cells (FOXP3+/CD4+ T) was lower in the ALLO compared to those in the SYN. Our results indicate that not only the B cell lineage but also the Th17 cells and their cytokine (IL-17) are involved in the sensitization to HLA.

β-lactoglobulin hydrolysates by L.plantarum AHQ-14 and L.bulgaricus BD0390 alleviate allergic responses to β-lactoglobulin in sensitized mice

The β-lactoglobulin (β-Lg) from cow whey protein is highly allergenic. β-Lg allergy often leads to digestive allergies or allergic gastroenteritis, damages intestinal micro ecological balance, and impacts on infant growth and health seriously. Milk protein can be partially degraded by lactic acid bacteria (LAB) and its allergenicity can be decreased to some extent. The immunological consequence of hydrolyzed β-Lg by L.plantarum AHQ-14 (H14) or L.bulgaricus BD0390 (H390) was investigated in a sensitized mouse model. BALB/c mice were stimulated with β-Lg or β-Lg hydrolysate sensitization, followed by oral stimulation of high doses of β-Lg or β-Lg hydrolysate sensitization. The results showed that β-Lg stimulated mice had increased the level of total IgE and IgG. Conversely, mice stimulated with H14 or H390 inhibited the allergic symptoms and reduced serum IgE/IgG levels. The H14 and H390 groups also decreased concentrations of mast cell protease-1 (mMCP-1) and plasma histamine (HIS), induced T helper (Th) 1 or T regulatory cells to regulate Th1/Th2 immune balance. Mice stimulated with H14 or H390 showed no signs of intestinal inflammation. They kept normal cytokine levels of IL-4 and IL-10 and increased IFN-γ production. Thus, H14 and H390 protected and avoided clinical allergy symptoms in sensitized mice, and have the potential to be used for β-Lg allergy to provide safe and effective treatment for infants with milk allergy.

Combined Use of Tocilizumab and Mesenchymal Stem Cells Attenuate the Development of an Anti-HLA-A2.1 Antibody in a Highly Sensitized Mouse Model.

Sensitization to HLA can result in allograft loss for kidney transplantation (KT) patients. Therefore, it is required to develop an appropriate desensitization (DSZ) technique to remove HLA-donor-specific anti-HLA antibody (DSA) before KT. The aim of this research was to investigate whether combined use of the IL-6 receptor-blocking antibody, tocilizumab (TCZ), and bone-marrow-derived mesenchymal stem cells (BM-MSCs) could attenuate humoral immune responses in an allo-sensitized mouse model developed using HLA.A2 transgenic mice. Wild-type C57BL/6 mice were sensitized with skin allografts from C57BL/6-Tg (HLA-A2.1)1Enge/J mice and treated with TCZ, BM-MSC, or both TCZ and BM-MSC. We compared HLA.A2-specific IgG levels and subsets of T cells and B cells using flow cytometry among groups. HLA.A2-specific IgG level was decreased in all treated groups in comparison with that in the allo-sensitized control (Allo-CONT) group. Its decrease was the most significant in the TCZ + BM-MSC group. Regarding the B cell subset, combined use of TCZ and BM-MSC increased proportions of pre-pro B cells but decreased proportions of mature B cells in BM (p < 0.05 vs. control). In the spleen, an increase in transitional memory was observed with a significant decrease in marginal, follicular, and long-lived plasma B cells (p < 0.05 vs. control) in the TCZ + BM-MSC group. In T cell subsets, Th2 and Th17 cells were significantly decreased, but Treg cells were significantly increased in the TCZ+BM-MSC group compared to those in the Allo-CONT group in the spleen. Regarding RNA levels, IL-10 and Foxp3 showed increased expression, whereas IL-23 and IFN-γ showed decreased expression in the TCZ + BM-MSC group. In conclusion, combined use of TCZ and BM-MSC can inhibit B cell maturation and up-regulate Treg cells, finally resulting in the reduction of HLA.A2-specific IgG in a highly sensitized mouse model. This study suggests that the combined use of TCZ and BM-MSC can be proposed as a novel strategy in a desensitization protocol for highly sensitized patients.

Combined use of tocilizumab (IL-6 receptor blocking antibody) and mesenchymal stem cells attenuate the development of anti-HLA-A2.1 antibody in highly sensitized mice model

Combined use of tocilizumab (IL-6 receptor blocking antibody) and mesenchymal stem cells attenuate the development of anti-HLA-A2.1 antibody in highly sensitized mice model

Comparison of immune responses and intestinal flora in epicutaneously sensitized BALB/c or C57BL/6 mouse models of food allergy

Cutaneous exposure to food allergens through a disrupted skin barrier is recognized as an important cause of food allergy, and the cutaneous sensitized mouse model has been established to investigate relevant allergic disorders. However, the role of different genetic backgrounds of mice on immune responses to food allergens upon epicutaneous sensitization is largely unknown. In this study, two strains of mice, i.e., the BALB/c and C57BL/6 mice, were epicutaneously sensitized with ovalbumin on atopic dermatitis (AD)-like skin lesions, followed by intragastric challenge to induce IgE-mediated food allergy. Allergic outcomes were measured as clinical signs, specific antibodies and cytokines, and immune cell subpopulations, as well as changes in intestinal barrier function and gut microbiota. Results showed that both strains of mice exhibited typical food-allergic symptoms with a Th2-skewed response. The C57BL/6 mice, rather than the BALB/c mice, were fitter for establishing an epicutaneously sensitized model of food allergy since a stronger Th2-biased response and severer disruptions in the intestinal barrier and gut homeostasis were observed. This study provides knowledge for selecting an appropriate mouse model to study food-allergic responses associated with AD-like skin lesions and highlights the role of genetic variations in the immune mechanism underlying pathogenesis of food allergy.

The role of memory T cells in Echinococcus granulosus-induced sensitization.

To investigate the changes in memory T cells and the related factors in mice by the establishment of a BALB/c mouse model of Echinococcus granulosus-induced sensitization. A sensitized BALB/c mouse model was established by intraperitoneal injection of E. granulosus. A control group (CTRL), a nonsensitized group infected with E. granulosus (CE), and a sensitized group infected with E. granulosus (ANPC) were set up. The pathological changes in lung tissue in mice, the change in memory T cells (CD4 Tm), and the change in peripheral blood nucleated interleukin-23 (IL-23) were detected using HE staining, flow cytometry, and liquid-phase multiple protein quantification techniques, respectively. The individual percentage of mouse memory T cells was 9.14 ± 0.45, 25.23 ± 0.17, and 13.29 ± 0.32 in the CTRL, CE, and ANPC groups, respectively. The percentage of memory T cells in the ANPC group was higher than that in the CTRL group (t = 18.410, p < .001) but lower than that in the CE group (t = -80.147, p < .001). The levels of IL-23 in peripheral blood of mice in the CTRL, CE, and ANPC groups were 225.76 ± 27.16, 359.21 ± 28.67, and 215.69 ± 22.69, respectively. The level of IL-23 in peripheral blood of mice in the ANPC group was lower than that in the CE group (t = 9.609, p < .001), and there was no statistical difference with the CTRL group (t = 0.697, p = .502). In the BALB/c mouse model of E. granulosus-induced sensitization, the expression of IL-23 in peripheral blood increased, and the memory T cell proliferated and became activated; there was a decrease in the content of IL-23 in peripheral blood and number of activated memory T cells in the sensitization group infected with E. granulosus. The E. granulosus-induced allergic reaction was related to IL-23 and the activation of memory T cells.

HDAC Downregulation of Xiaoqinglong Decoction in the Treatment of Allergic Rhinitis

Introduction: As one of the most common allergic diseases, allergic rhinitis (AR) has attracted wide attention all over the world. More appropriate treatment of AR should be explored thoroughly. In recent years, traditional Chinese medicine has attracted more attention in AR treatment. As a classical Chinese medicine prescription, Xiaoqinglong decoction (XQLD) has been commonly used in treating AR. Even though its therapeutic effect on AR has been clinically confirmed, more molecular mechanism remains to be further investigated. Our research aimed to investigate the therapeutic mechanism of XQLD for AR management. Methods: The study was evaluated in an ovalbumin sensitized mouse model and liquid chromatography-mass spectrometry was adopted to test the stability of XQLD’s effective components. Results: The results confirmed the stability and safety of the effective components of XQLD. XQLD significantly downregulated the expression of HDACs (HDAC1, HDAC3, and HDAC4) and Th2 inflammatory factors (IL4, IL5, and IL13) in AR mice. XQLD and the HDAC inhibitor JNJ-26481585 promoted the expression of epithelial tight junction proteins (claudin-1 and ZO-1) and decreased the expression of mucins (Muc5ac and Muc5b) in the nasal mucosa of AR mice. Conclusions: In conclusion, our findings present the beneficial effects of XQLD on AR and recovery of the nasal epithelium. We also identify the decreased HDAC as a potential target of XQLD for AR treatment. This study provides an important experimental proof for elucidating the therapeutic mechanism of XQLD.

2'-Fucosyllactose alleviates OVA-induced food allergy in mice by ameliorating intestinal microecology and regulating the imbalance of Th2/Th1 proportion.

Food allergy (FA) has become a prominent problem in public health. 2'-Fucosyllactose (2'-FL) was reported to alleviate FA symptoms; however, the regulatory mechanism is still unclear. This study evaluated the 2'-FL antiallergic potential in an ovalbumin (OVA)-sensitized mouse model and explored the systemic effects of 2'-FL on gut microecology and the intestinal immune barrier. The results showed that 2'-FL alleviated allergy symptoms, decreased serum allergic indicator levels, enhanced the intestinal barrier, and attenuated low-grade inflammation. The up-regulation of G protein-coupled receptors (GPRs) was associated with higher levels of short-chain fatty acids (SCFAs) in 2'-FL intervention mice. 2'-FL also improved the intestinal microbiota diversity and increased the abundance of Akkermansia, Lachnospiraceae UCG-006, and Ruminococcaceae while suppressing Muribaculaceae, Desulfovibrionaceae, and Erysipelotrichaceae. Additionally, 2'-FL ameliorated the imbalance of Th2/Th1, mainly by decreasing Th2-type immune response and enhanced CD4 + Foxp3 + Treg immunoreaction. These results suggest that 2'-FL restores intestinal barrier defects, gut microbiota disorder, and immune impairment while alleviating ovalbumin-induced allergic symptoms in FA mice.

Multi-omics reveals the mechanisms of DEHP driven pulmonary toxicity in ovalbumin-sensitized mice

The plasticizer di- (2-ethylhexyl) phthalate (DEHP) is considered a risk factor for allergic diseases and has attracted public attention for its adverse effects on health. However, respiratory adverse effects after DEHP exposure in food allergies have rarely been reported. MiRNAs are considered to be key regulators in the complex interrelationships between the host and microbiome and may be a potential factor involved in DEHP-induced pulmonary toxicity. To investigate the adverse effects of DEHP on the lung during sensitization, we established an ovalbumin (OVA)-sensitized mouse model exposed to DEHP and performed 16S rDNA gene sequencing, miRNA sequencing, and correlation analysis. Our results showed that DEHP aggravated the immune disorder in OVA-sensitized mice, which was mainly characterized by an increase in the proportion of Th2 lymphocytes, and further enhanced OVA-induced airway inflammation without promoting pulmonary fibrosis. Compared with the OVA group, DEHP interfered with the lung microbial community, making Proteobacteria the dominant phylum, while Bacteroidetes were significantly reduced. Differentially expressed miRNAs were enriched in the PI3K/AKT pathway, which was closely related to immune function and airway inflammation. The expression of miR-146b-5p was elevated in the DEHP group, which was positively correlated with the proportion of Th2 cells and significantly negatively correlated with the abundance of Bacteroidetes. The results indicate that DEHP may interfere with the expression of miR-146b-5p, affect the composition of the lung microbiota, induce an imbalance in T cells, and lead to immune disorders and airway inflammation. The current study uses multi-omics to reveal the potential link between the plasticizer DEHP and allergic diseases and provides new insights into the ecotoxicology of environmental exposures to DEHP.

Discovery of cellular and molecular pathways involved in the development of anti-human leukocyte antigen antibody through single cell RNA sequencing in highly sensitized mouse model

Discovery of cellular and molecular pathways involved in the development of anti-human leukocyte antigen antibody through single cell RNA sequencing in highly sensitized mouse model

The roles of K+-dependent Na+/Ca2+ exchanger 2 (NCKX2) in methamphetamine-induced behavioral sensitization and conditioned place preference in mice

Drug addiction, including methamphetamine (METH) addiction, is a significant public health and social issue. Perturbations in intracellular Ca2+ homeostasis are associated with drug addiction. K+-dependent Na+/Ca2+ exchanger 2 (NCKX2) is located on neuronal cell membranes and constitutes a Ca2+ clearance mechanism, with key roles in synaptic plasticity. NCKX2 is associated with motor learning, memory, and cognitive functions. However, the role of NCKX2 in METH addiction remains unclear. In this study, we investigated the expression levels of NCKX2 in four addiction-related brain regions: the prefrontal cortex (PFc), nucleus accumbens (NAc), dorsal striatum (DS), and hippocampus (Hip) in a C57/BL6 mouse model of METH-induced conditioned place preference (CPP) and behavioral sensitization. Levels of NCKX2 were unchanged in these brain regions in mice with METH-induced CPP but were decreased in the PFc and NAc of mice with METH-induced behavioral sensitization. Adeno-associated virus (AAV)-mediated overexpression of NCKX2 in the PFc attenuated the expression phase of METH-induced behavioral sensitization in mice, whereas AAV-mediated knockdown of NCKX2 enhanced the effects of METH. Collectively, our results suggest that NCKX2 is involved in METH-induced behavioral sensitization but does not affect conditioned reward-related memory, highlighting the potential of NCKX2 as a molecular target for studying the mechanisms underscoring METH addiction.

Effects of mitochondrial reactive oxygen species-induced NLRP3 inflammasome activation on trichloroethylene-mediated kidney immune injury.

This study aimed to investigate the activating mechanism of the NLRP3 inflammasome in trichloroethylene-sensitized mice. In total, 88 BALB/c female mice were used to establish the trichloroethylene (TCE)-sensitized mouse model. Some of the mice received MitoTEMPO, MCC 950 or soluble recombinant CD59-Cys to inhibit mitochondrial reactive oxygen species (mtROS) production, NLRP3 assembly, or C5b-9 formation. Mouse tubular epithelial cell expression levels of NLRP3, ASC, Caspase 1, IL-1β, IL-18 and mitochondrial antiviral signaling protein (MAVS) were detected by western blot. Mitochondrial numbers, membrane potential (ΔΨm) and mtROS were detected by using MitoScene Green II, JC-1 dye and MitoSOX Red indicator, respectively. Tubular epithelial cell calcium levels were detected by a Fluo-8 no wash calcium assay kit. Human kidney-2 (HK-2) cells were cultured and stimulated by C5b6 and normal human serum (NHS) to verify the role of C5b-9-induced mitochondrial ROS in activating NLRP3 inflammasome. Urine α1-MG, β2-MG, and mtROS production and calcium levels were increased, while mitochondrial numbers were decreased in TCE-sensitized positive mice. After treatment with MitoTEMPO, renal tubular injury was alleviated, JC-1 fluorescence and mitochondrial numbers were significantly increased, and mitochondrial ROS were inhibited. The NLRP3 inflammasome was activated in TCE-sensitized positive mice, while Mito TEMPO inhibited MAVS expression and NLRP3 inflammasome activation. The in vitro studies proved that C5b-9 can induce mtROS release and activate the assembly of NLRP3 inflammasome in HK-2 cells. In conclusion, in TCE-sensitized positive mouse renal tubular epithelial cells, C5b-9 caused calcium influx and thus induced mitochondrial injury and mtROS overexpression, finally inducing MAVS expression and NLRP3 inflammasome activation and kidney injury.

ROS-mediated inflammatory response in liver damage via regulating the Nrf2/HO-1/NLRP3 pathway in mice with trichloroethylene hypersensitivity syndrome

Trichloroethylene hypersensitivity syndrome (THS), mainly caused by occupational exposure to trichloroethylene (TCE), can give rise to serious and fatal hepatic damage. To date, the precise mechanisms of hepatic damage in THS remain unclear. Recent studies showed that reactive oxygen species (ROS) play a core role in cell death and inflammatory response. Therefore, the present study sought to explore whether ROS-mediated inflammatory responses contribute to the hepatic damage in TCE sensitization. To this end, a mouse model of TCE sensitization was established; in some cases, hosts were pretreated with tempol, an ROS scavenger. The results showed that TCE sensitization caused hepatic pathological/functional changes, ROS generation, and oxidative stress, alterations of the anti-oxidant defense Nrf2/HO-1/NLRP3 pathway, and pro-inflammatory cytokine formation in the liver. ROS scavenging via pretreatment with tempol was found not only to inhibit the hepatic oxidative stress, but also to regulate Nrf2/HO-1/NLRP3 pathway activity. In all cases, tempol was able to mitigate the pathologic changes induced by TCE sensitization. In summary, the results here demonstrated a novel molecular mechanism wherein ROS-mediated inflammatory responses play a central role in TCE-induced liver damage. Therapies targeting ROS scavenging could help to protect against hepatic damage by regulating Nrf2/HO-1/NLRP3 pathway activities in TCE-sensitized hosts.

Abstract P110: Differential Gene Expression Associated With Ccn1-positive Renal Cells In Murine Hypertensive Models

Hypertension affects roughly half of the U.S. population and is characterized by detrimental pro-inflammatory changes that alter renal function and the cardiovascular system over time. The kidney is a major regulator of blood pressure, however, the specific contributions of renal cell types, including lymphatic endothelial cells (LECs), to hypertension have not been thoroughly explored. Previous work from our lab has shown an increase in renal lymphangiogenesis in response to hypertension and that augmentation of renal lymphangiogenesis can reduce blood pressure. CCN1/Cyr61 is an extracellular matrix protein secreted by multiple cell types, particularly LECs and fibroblasts, which contributes to integrin signaling pathways. CCN1 is also known to be involved in lymphangiogenesis, and has previously been implicated in GWAS studies of hypertension. Given these connections, we performed single cell RNA sequencing using angiotensin II and salt sensitive mouse models of hypertension, which were analyzed separately as well as aggregated into one hypertensive group. Kidneys were turned to a single cell suspension and separated for CD31+/Podoplanin+ cells meant to better represent LECs, which are a small fraction of renal cells. Sequencing was performed and the gene reads were run through the Cell Ranger, Seurat, FGSEA, and Slingshot pipelines, then CCN1+ cells were isolated digitally and analyzed separately. In the AngII model, a total of 60 genes (28 up, 32 down) were differentially expressed (p&lt;0.01) between the renal CCN1+ cells in the hypertensive mice compared to controls, while the salt sensitive model had a total of 331 differentially expressed genes (305 up, 26 down). When the hypertension groups were merged, there were a total of 600 differentially expressed genes (503 up, 97 down) with GSEA showing 48 pathways with enrichment scores &gt;3 or &lt;-3. Additionally, the cellular profile of CCN1+ cells shifted, branching out from a fibroblast-like population to other cell types such as endothelium and tubular epithelium. Overall, the expression of CCN1+ renal cells demonstrates notable changes in response to hypertension in murine models and encourages further study of the mechanisms behind CCN1’s role in the development and maintenance of hypertension.

Trichloroethylene induces immune renal tubular injury through SIRT 1/HSP 70/TLR 4 pathway in BALBc mice

Trichloroethylene (TCE) is a volatile chlorinated solvent widely used for cleaning and degreasing industrial metal parts. Due to the widespread use and improper disposal of TCE, exposure to TCE causes a variety of adverse effects on human and animal health. However, the underlying mechanism of the damage remains unclear. The purpose of this study is to investigate the role of Sirtuin-1 (SIRT 1) in TCE-induced immune renal tubular injury. 6–8-week-old female BALB/c mice were used to construct a TCE sensitized mouse model. SIRT 1 activator, SRT 1720 (0.1 ml, 5 mg/kg) and toll like receptor 4 (TLR 4) inhibitor, TAK-242 (0.1 ml, 3 mg/kg) were used for treatment. Results show that SIRT 1 and heat shock protein 70 (HSP 70) levels are significantly down-regulated in renal tubules, serum and urine HSP 70 levels are significantly increased, and inflammatory cytokines levels are significantly increased in renal tubules in TCE-sensitized positive mice. After SRT 1720 treatment, intracellular HSP 70 level is significantly increased and extracellular HSP 70 level is decreased, and inflammatory cytokines levels get alleviated. In addition, HSP 70 and Toll-like Receptor 4 (TLR 4) proteins exist an interaction that can be significantly attenuated by SIRT 1. Subsequently, inflammation of the renal tubules mediated by SIRT 1 downregulation is attenuated after TAK-242 treatment. In conclusion, SIRT 1 alleviates renal tubular epithelial cells immune injury by inhibiting the release of HSP 70 and thereby weakening interaction with HSP 70 and TLR 4.

Dietary olive oil enhances the oral tolerance of the food allergen ovalbumin in mice by regulating intestinal microecological homeostasis.

Increasing evidence indicates that intestinal microecological imbalances are strongly associated with food allergen intolerance. This study investigated the effect of olive oil on food allergy susceptibility and intestinal microecology based on an ovalbumin (OVA)-sensitized mouse model. The results indicated that the allergic symptoms of sensitized mice were alleviated when they were supplemented with olive oil at 1-3g/kg per day for 7 weeks. Intestinal epithelium observation showed repaired ileum villi and upregulated tight junction (TJ) protein expression. Furthermore, the levels of the cytokines (e.g., IL-10) secreted by regulatory T cells were increased, whereas T helper 2 (Th2) cell-associated factors were decreased in lamina propria. Furthermore, 16S rRNA sequencing indicated reduced Burkholderiaceae and increased Clostridiaceae in the intestinal microflora. The results suggest that an olive oil-enriched diet may effectively prevent food allergies by regulating the intestinal microecological balance. PRACTICAL APPLICATIONS: Recent studies emphasized that intestinal ecological imbalance, including intestinal immunity and microflora structure, plays an important role in affecting the occurrence and development of food allergy. The present results implied that olive oil, one of the main components of the Mediterranean diet, can effectively ameliorate the symptoms of OVA-induced food allergy by regulating intestinal microecological homeostasis. Therefore, dietary supplementation with olive oil may be an effective strategy for preventing food allergies.

Long-term respiratory exposure to amorphous silica nanoparticles promoted systemic inflammation and progression of fibrosis in a susceptible mouse model

Exposure to amorphous silica nanoparticles (SiNPs) has increased dramatically, and concerns are growing about their potential health effects. However, their long-term systemic toxicity profile and underlying mechanisms following respiratory exposure still remains unexplored. It is well documented that the inhalation of ultrafine particles is firmly associated with adverse effects in humans. Environmental pollutants may contribute to diverse adverse effect or comorbidity in susceptible individuals. Thereby, we examined the long-term systemic effects of inhaled SiNPs using a sensitive mouse model (ApoE-/-) fed by a western diet. Male ApoE-/- mice were intratracheally instilled with SiNPs suspension at a dose of 1.5, 3.0 and 6.0 mg/kg·bw, respectively, once per week, 12 times in total. The histological analysis was conducted. The serum cytokine levels were quantified by RayBiotech antibody array. As a result, systemic histopathological alterations were noticed, mainly characterized by inflammation and fibrosis. More importantly, cytokine array analysis indicated the key role of mast cells accumulation in systemic inflammation and fibrosis progression induced by inhaled SiNPs. Collectively, our study firstly demonstrated that long-term exposure to inhaled SiNPs promoted the mast cell-dominated activation of inflammatory response, not only in the lung but also in heart, liver and kidney, etc., eventually leading to the progression of tissue fibrosis in ApoE-/- mice.

Evaluation of stable reference genes for qPCR normalization in circadian studies related to lung inflammation and injury in mouse model

Circadian rhythms have a profound effect on lung function and immune-inflammatory response in chronic airway diseases. Thus, understanding the molecular mechanisms of circadian gene expression of core clock-controlled genes (CCGs) may help better understand how it contributes to the physiology and pathology of lung diseases. Ongoing studies have been analyzing gene expression levels of CCGs in mouse lungs using quantitative real-time PCR (qRT-PCR). However, to date, there are no reports on the most stable reference gene in the mouse lung for circadian studies. Herein, we utilized an acute house dust mite (HDM)-sensitization mouse model to evaluate the stability of 10 reference genes commonly used for qRT-PCR normalization using 5 unique algorithms: GeNorm, NormFinder, BestKeeper, RefFinder and Qbase+. Rn18s was determined as the most stable reference gene across all samples evaluated, and Actb, the least stable reference gene. Furthermore, CircWave analysis showed no diurnal variation in the expression pattern for Rn18s but Actb showed strong diurnal changes in the lungs of both PBS (control) and HDM groups. We demonstrate systematically how using Actb as a housekeeping gene offsets the diurnal expression patterns of the CCGs and leads to statistically significant results which may not be the true reflection of the qRT-PCR analysis.