ABSTRACT
BACKGROUND/AIM: In a previous report, our group showed that oral administration of lipopolysaccharides (LPS) from Pantoea agglomerans can prevent the progression of streptozotocin (STZ)-induced diabetes-related cognitive dysfunction (DRCD) in mice without causing significant side-effects. However, the treatment effects of oral administration of LPS to DRCD remain unknown. MATERIALS AND METHODS: We modified our previous animal experimental model to investigate whether oral administration of LPS can recover cognitive function after DRCD onset. RESULTS: The Morris water maze (MWM) revealed a significant decrease in learning and memory abilities at 13 days after intracerebroventricular administration of STZ, thereby providing evidence of the occurrence of DRCD in the animal model. Oral administration of LPS (1 mg/kg per day) started after cognitive impairment was observed. After 28 days of treatment, mice receiving LPS via the oral route showed significant recovery of spatial learning ability, a symptom of early dementia, while only a trend toward recovery was seen for spatial memory compared to the untreated group. CONCLUSION: These results, limited to MWM, suggest that oral administration of LPS is a promising therapeutic strategy for restoring decreased spatial learning ability.
Subject(s)
Cognitive Dysfunction , Diabetes Mellitus, Experimental , Disease Models, Animal , Lipopolysaccharides , Maze Learning , Spatial Learning , Animals , Lipopolysaccharides/adverse effects , Lipopolysaccharides/administration & dosage , Mice , Administration, Oral , Cognitive Dysfunction/etiology , Cognitive Dysfunction/drug therapy , Male , Diabetes Mellitus, Experimental/complications , Spatial Learning/drug effects , Maze Learning/drug effects , Streptozocin/administration & dosageABSTRACT
The objective of this research was to determine the effects of mid-gestational maternal inflammation on performance, carcass characteristics, and meat quality of offspring. Pregnant gilts were administered either lipopolysaccharide (LPS; nâ =â 7) or saline (CON, nâ =â 7) from days 70 to 84 of gestation. Gilts assigned to the LPS treatment were administered an intravenous injection of reconstituted LPS every other day with a beginning dose of 10 µg LPS/kg body weight and subsequent doses increasing by 12%, while CON gilts received intravenous injections of comparable volumes of saline. Gilts farrowed naturally, and at day 66 of age, a total of 59 pigs, both barrows and gilts began a 3-phase feeding regimen designed to meet or exceed nutrient requirements for growing-finishing pigs. Pigs were weighed on days 0, 35, 70, and 105 of the finishing trial to determine average daily gain, average daily feed intake, and gain-to-feed ratio (G:F). On day 106, pigs were slaughtered under the supervision of the U.S. Department of Agriculture Food Safety Inspection Service. Ending live weight, hot carcass weight, and dressing percentage were determined. The left side of carcasses was weighed and fabricated to determine carcass cutting yields. The semitendinosus was collected for histological samples. Fresh belly characteristics and loin quality were measured. Two chops were collected for Warner-Bratzler shear force and proximate analysis. No differences (Pâ ≥â 0.13) between LPS and CON pigs were observed for growth performance in phases 1, 2, 3, or overall (days 0 to 105) performance with the exception of overall G:F reduced in CON pigs compared with LPS pigs (Pâ =â 0.03). There was a tendency for carcass yield to be reduced (Pâ =â 0.06; 0.82% units) in LPS pigs compared with CON pigs. Additionally, longissimus muscle area tended to be reduced (Pâ =â 0.10) 2.27 cm2 in LPS compared with CON pigs. Loin chop quality traits including instrumental color, subjective color, marbling, firmness, pH, and drip loss were not different (Pâ ≥â 0.09) between LPS and CON pigs. Fresh belly characteristics were not different (Pâ ≥â 0.22) between LPS and CON pigs. There were no differences in primal and subprimal weights, except that LPS pigs tended to have a reduction (Pâ ≥â 0.07) in tenderloin and Canadian back weights compared with CON pigs. Furthermore, LPS pigs had no differences (Pâ ≥â 0.25) in muscle fiber composition or size; however, LPS pigs tended (Pâ =â 0.10) to have a 13% reduction in estimated muscle fibers number compared with CON pigs. In summary, mid-gestational inflammation did not result in reduced meat quality, growth performance, or carcass yields of offspring.
Gestation is a crucial time for communicating the outside environment to the fetus. Any influence on the fetus during gestation may have lifelong effects on the offspring. Most muscle fiber formation occurs in the beginning of the third trimester of gestation. Therefore, maternal inflammation during this period may be detrimental to fetal muscle development, which can ultimately stunt growth potential and influence carcass characteristics and meat quality. A majority of previous research that investigates maternal inflammation as a result of innate immune activation focuses on neuropsychiatric disorders in the offspring, offering little relevance to animal agriculture. The influence of maternal infection on long-term growth performance, carcass characteristics, and meat quality has received little attention. Therefore, the objective of this study was to elucidate the impact of maternal inflammation on offspring growth, efficiency, carcass characteristics, and pork quality. The gestational challenge resulted in pigs that tended to have fewer total muscle fibers. However, gestational inflammation did not have an impact on overall growth performance, carcass characteristics, or pork quality of the offspring.
Subject(s)
Inflammation , Lipopolysaccharides , Meat , Animals , Female , Pregnancy , Lipopolysaccharides/pharmacology , Lipopolysaccharides/administration & dosage , Swine/growth & development , Swine/physiology , Inflammation/veterinary , Inflammation/chemically induced , Meat/analysis , Meat/standards , Male , Body Composition/drug effects , Swine DiseasesABSTRACT
OBJECTIVES: Endothelial-to-mesenchymal transition (EndoMT) is a significant biological phenomenon wherein endothelial cells undergo a loss of their endothelial traits and progressively acquire mesenchymal characteristics. Consequently, this transformation leads to both a compromised ability to maintain lumen permeability and alterations in vascular structure, which hampers the preservation of blood-brain barrier integrity. This study aimed to investigate inflammation-induced EndoMT and its etiology, with the goal of impeding the infiltration of peripheral inflammation into the central nervous system. MATERIALS AND METHODS: Lipolysaccharide (LPS) was administered intraperitoneally to mice several times to establish a chronic inflammatory model. A cellular inflammatory model was established by LPS in human brain microvascular endothelial cells (HBMECs). The mRNA expressions of inflammatory cytokines interleukin-1ß (IL-1ß) and IL-6 were detected by real-time polymerase chain reaction (PCR). Immunofluorescence staining of platelet endothelial cell adhesion molecule-1 (CD31) and alpha smooth muscle actin (α-SMA) was conducted to assess the level of EndoMT. The expression levels of Occludin, zona occludens protein 1 (ZO-1), Sestrin2, microtubule-associated protein1 light chain 3 (LC3) and inducible nitric oxide synthase (iNOS) were detected by western blotting. RESULTS: LPS treatment induced the downregulation of ZO-1 and Occludin, which was accompanied by the elevated expressions of iNOS, α-SMA, Sestrin2 and LC3-II in the mouse cortex and HBMECs. Mechanistically, the knockdown of Sestrin2 in HBMECs exacerbated the EndoMT induced by LPS treatment, while the overexpression of Sestrin2 inhibited this process. Moreover, the induction of autophagy by rapamycin rescued the EndoMT induced by Sestrin2 knockdown. CONCLUSION: This study revealed that Sestrin2 inhibited endothelial inflammation and EndoMT via enhanced autophagy, which may provide a potential drug target for cerebrovascular inflammatory injury.
Subject(s)
Autophagy , Endothelial Cells , Lipopolysaccharides , Animals , Lipopolysaccharides/pharmacology , Lipopolysaccharides/administration & dosage , Mice , Autophagy/drug effects , Autophagy/physiology , Humans , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Mice, Inbred C57BL , Male , Epithelial-Mesenchymal Transition/drug effects , Epithelial-Mesenchymal Transition/physiology , Nuclear Proteins/metabolism , Inflammation/metabolism , Disease Models, AnimalABSTRACT
This study was conducted to investigate the protective effects of chlorogenic acid (CGA) on inflammatory responses and intestinal health of lipopolysaccharide (LPS)-challenged broilers. One hundred and forty-four 1-day-old male broiler chicks were divided into 3 groups with 6 replicates of 8 birds each. The groups were as follows: 1) Control group: birds fed a basal diet; 2) LPS group: LPS-challenged birds fed a basal diet; 3) CGA group: LPS-challenged birds fed a CGA-supplemented diet. The LPS was intraperitoneally administered at a dose of 1 mg/kg of body weight. CGA increased the weight gain and feed intake of LPS-challenged birds by 37.05% and 24.29%, respectively (P < 0.05). CGA also alleviated LPS-induced inflammation, as evidenced by lower levels of pro-inflammatory cytokines in the serum and jejunum (tumor necrosis factor-α, interferon-γ, interleukin-1ß, and interleukin-6), and the decreased myeloperoxidase activity in the jejunum (P < 0.05). These effects were accompanied by a decrease in the mRNA abundance of toll-like receptor 4 and myeloid differentiation factor 88 and an inhibition of nuclear factor kappa-B translocation in the jejunum (P < 0.05). CGA reduced circulating diamine oxidase activity and levels of D-lactate and endotoxin, and positively regulated the expression of jejunal claudin-3 and zonula occludens-1 in LPS-challenged broilers (P < 0.05). Compared to the LPS group, CGA reduced the apoptotic rate of epithelial cells and cytochrome c concentration in the jejunum, and normalized the expression of genes responsible for proliferation and apoptosis in jejunal epithelial cells, including cysteine aspartate-specific protease-9, B cell lymphoma-2, and proliferating cell nuclear antigen (P < 0.05). Furthermore, CGA normalized the altered phosphorylation of protein kinase B and glycogen synthase kinase-3ß, as well as the translocation of nuclear ß-catenin in the jejunum of LPS-challenged broilers (P < 0.05). These results suggested that CGA supplementation improved growth performance, alleviated inflammation, and helped maintain intestinal integrity and barrier function in LPS-challenged broilers, possibly through the regulation of the toll-like receptor 4/nuclear factor kappa-B and protein kinase B/Wnt/ß-catenin pathways.
Subject(s)
Animal Feed , Chickens , Chlorogenic Acid , Diet , Lipopolysaccharides , Animals , Chlorogenic Acid/administration & dosage , Chlorogenic Acid/pharmacology , Male , Lipopolysaccharides/administration & dosage , Diet/veterinary , Animal Feed/analysis , Dietary Supplements/analysis , Random Allocation , Inflammation/veterinary , Inflammation/chemically induced , Inflammation/drug therapy , Intestines/drug effects , Poultry Diseases/chemically induced , Poultry Diseases/prevention & control , Stress, Physiological/drug effectsABSTRACT
The present work aimed to study whether a high sugar diet can alter immune responses and the gut microbiome in green iguanas. Thirty-six iguanas were split into four treatment groups using a 2×2 design. Iguanas received either a sugar-supplemented diet or a control diet, and either a lipopolysaccharide (LPS) injection or a phosphate-buffered saline (PBS) injection. Iguanas were given their respective diet treatment through the entire study (â¼3â months) and received a primary immune challenge 1 and 2 months into the experiment. Blood samples and cloacal swabs were taken at various points in the experiment and used to measure changes in the immune system (bacterial killing ability, lysis and agglutination scores, LPS-specific IgY concentrations), and alterations in the gut microbiome. We found that a sugar diet reduces bacterial killing ability following an LPS challenge, and sugar and the immune challenge temporarily alters gut microbiome composition while reducing alpha diversity. Although sugar did not directly reduce lysis and agglutination following the immune challenge, the change in these scores over a 24-h period following an immune challenge was more drastic (it decreased) relative to the control diet group. Moreover, sugar increased constitutive agglutination outside of the immune challenges (i.e. pre-challenge levels). In this study, we provide evidence that a high sugar diet affects the immune system of green iguanas (in a disruptive manner) and alters the gut microbiome.
Subject(s)
Diet , Gastrointestinal Microbiome , Iguanas , Animals , Gastrointestinal Microbiome/drug effects , Iguanas/immunology , Iguanas/microbiology , Diet/veterinary , Lipopolysaccharides/administration & dosage , Animal Feed/analysis , Dietary Sugars/administration & dosageABSTRACT
The aim of this study was to establish a multi-factor-induced depression model in mice within a relatively short period, specifically through the combination of intraperitoneal injection of lipopolysaccharide (LPS) and chronic restraint stress (CRS), and to evaluate the differences in depressive-like behaviors among three different strains of mice, seeking mouse strains more suitable for this combined model. The mice of each strain were randomly divided into the normal group and model group. The mice in the model group received a single intraperitoneal injection of LPS once daily (1 mg/kg/d for 7 days) and subsequent CRS for 6 h, to induce depression, while the mice in the normal group received no treatment. Behavioral tests: sucrose preference test (SPT), open field test (OFT), forced swim test (FST), and tail suspension test (TST) were conducted to assess depressive-like behaviors in the mice. Data analysis showed that there were significant intergroup differences in depressive-like behaviors in ICR and C57BL/6 J mice, while KM mice exhibited minor differences with relatively high deviation in individual behavioral score. This study indicated that the combined depression mouse model could successfully induce significant depressive-like behaviors in ICR and C57BL/6 J mice.
Subject(s)
Depression , Disease Models, Animal , Lipopolysaccharides , Mice, Inbred C57BL , Restraint, Physical , Stress, Psychological , Animals , Lipopolysaccharides/pharmacology , Lipopolysaccharides/administration & dosage , Mice , Male , Depression/etiology , Depression/physiopathology , Mice, Inbred ICR , Hindlimb Suspension , Swimming , Species Specificity , Motor Activity/physiology , Motor Activity/drug effectsABSTRACT
The treatment of severe acute pancreatitis (SAP), with high mortality rates, poses a significant clinical challenge. Investigating the pathological changes associated with SAP using animal models can aid in identifying potential therapeutic targets and exploring novel treatment approaches. Previous studies primarily induced pancreatic injury through retrograde bile duct injection of sodium taviaurocholate, but the impact of surgical damage on the quality of the animal model remains unclear. In this study, we employed various frequencies of intraperitoneal Caerulein injections combined with different doses of LPS to induce pancreatic injury in C57BL/6J mice and compared the extent of injury across five intraperitoneal injection protocols. Regarding inducing acute pancreatitis in mice, an intraperitoneal injection protocol is proposed that results in a mortality rate as high as 80% within 5 days. Specifically, mice received ten daily intraperitoneal injections of Caerulein (50 µg/kg), followed by an injection of LPS (15 mg/kg) one hour after the last Caerulein administration. By adjusting the frequency and dosage of injected medications, one can manipulate the severity of pancreatic injury effectively. This model exhibits strong controllability and has a short replication cycle, making it feasible for completion by a single researcher without requiring expensive equipment. It conveniently and accurately simulates key disease characteristics observed in human SAP while demonstrating a high degree of reproducibility.
Subject(s)
Ceruletide , Disease Models, Animal , Lipopolysaccharides , Mice, Inbred C57BL , Pancreatitis , Animals , Mice , Pancreatitis/pathology , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/toxicity , Injections, Intraperitoneal , Male , Acute DiseaseABSTRACT
Recent studies have demonstrated that stress during the critical windows of development can evoke a cascade of neurological changes that can result in neuropsychiatric disorders later in life. In this study, we examined the effect of early-life inflammation on ethanol consumption in adolescent mice. C57BL/6J mice were assigned to either the control or Lipopolysaccharide (LPS) group on postnatal day 14 (P14). In the latter group, LPS at a dose of 50 µg/kg was injected intraperitoneally. The mice were weaned at P21, and behavior tests were performed at P45. Ethanol consumption was assessed using a two-bottle choice drinking paradigm. Anxiety-like behaviors were assessed by marble burying test (MBT), open field (OF), and elevated plus maze (EPM). Ethanol-induced loss of righting reflex (LORR), hypothermia and ethanol metabolism were assessed to evaluate ethanol intoxication. P14 LPS-injected adolescent male mice exhibited significantly increased ethanol preference and consumption, with a similar taste preference for saccharin and avoidance of quinine. The adolescent male mice showed increased anxiety-like behaviors in the OF and EPM tests, and an increased duration of LORR, without affecting the hypothermic effects of ethanol and ethanol metabolism. Interestingly, these behavioral changes were not obvious in female mice. In conclusion, our data indicate that early-life inflammation may be a risk factor for ethanol consumption in adolescents with greater changes observed in male mice. SIGNIFICANCE STATEMENT: Our study is the first preclinical model to report the enhancement effect of early-life inflammation on ethanol consumption in adolescent male mice and our findings provide a valuable mouse model to examine the neurobiological mechanisms mediating the long-lasting effects of early-life inflammation on alcohol use disorders vulnerability.
Subject(s)
Alcohol Drinking , Anxiety , Ethanol , Inflammation , Lipopolysaccharides , Mice, Inbred C57BL , Animals , Male , Mice , Inflammation/chemically induced , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/toxicity , Ethanol/administration & dosage , Alcohol Drinking/psychology , Female , Anxiety/chemically induced , Behavior, Animal/drug effects , Reflex, Righting/drug effectsABSTRACT
In the large poultry industry, where farmed chickens are fed at high density, the prevalence of pathogens and repeated vaccinations induce immune stress, which can significantly decrease the production performance and increase the mortality. This study was designed to shed light on the molecular mechanisms and metabolic pathways involved in immune stress through an in-depth analysis of transcriptomic and metabolomic changes in jejunum samples from the broilers. Two groups were established for the experiment: a control group and an LPS group. LPS group received an intraperitoneal injection of LPS solution at a dose of 250 µg per kg at 12, 14, 33, and 35 d of age, whereas the control group received a sterile saline injection. The severity of immune stress was assessed using the Disease Activity Index. A jejunal section was collected to measure the intestinal villus structure (villus length and crypt depth). RNA sequencing and metabolomics data analysis were conducted to reveal differentially expressed genes and metabolites. The results showed that the DAI index was increased and jejunal villus height/crypt depth was decreased in the LPS group. A total of 96 differentially expressed genes and 672 differentially accumulating metabolites were detected in the jejunum by LPS group compared to the control group. The comprehensive analysis of metabolomic and transcriptomic data showed that 23 pathways were enriched in the jejunum and that appetite, nutrient absorption, energy and substance metabolism disorders and ferroptosis play an important role in immune stress in broilers. Our findings provide a deeper understanding of the molecular and metabolic responses in broilers to LPS-induced immune stress, suggesting potential targets for therapeutic strategies to improve the production performance of broiler chickens.
Subject(s)
Chickens , Jejunum , Stress, Physiological , Transcriptome , Animals , Chickens/physiology , Chickens/immunology , Chickens/genetics , Jejunum/metabolism , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/pharmacology , Poultry Diseases/immunology , Poultry Diseases/genetics , Poultry Diseases/metabolism , Metabolome , Male , Metabolomics , Gene Expression Profiling/veterinaryABSTRACT
Endotoxin administration is commonly used to study the inflammatory response, and though traditionally given as a bolus injection, it can be administered as a continuous infusion over multiple hours. Several studies hypothesize that the latter better represents the prolonged and pronounced inflammation observed in conditions like sepsis. Yet very few experimental studies have administered endotoxin using both strategies, leaving significant gaps in determining the underlying mechanisms responsible for their differing immune responses. We used mathematical modelling to analyse cytokine data from two studies administering a 2 ng kg-1 dose of endotoxin, one as a bolus and the other as a continuous infusion over 4 h. Using our model, we simulated the dynamics of mean and subject-specific cytokine responses as well as the response to long-term endotoxin administration. Cytokine measurements revealed that the bolus injection led to significantly higher peaks for interleukin (IL)-8, while IL-10 reaches higher peaks during continuous administration. Moreover, the peak timing of all measured cytokines occurred later with continuous infusion. We identified three model parameters that significantly differed between the two administration methods. Monocyte activation of IL-10 was greater during the continuous infusion, while tumour necrosis factor α $ {\alpha} $ and IL-8 recovery rates were faster for the bolus injection. This suggests that a continuous infusion elicits a stronger, longer-lasting systemic reaction through increased stimulation of monocyte anti-inflammatory mediator production and decreased recovery of pro-inflammatory catalysts. Furthermore, the continuous infusion model exhibited prolonged inflammation with recurrent peaks resolving within 2 days during long-term (20-32 h) endotoxin administration.
Subject(s)
Cytokines , Endotoxins , Humans , Endotoxins/administration & dosage , Endotoxins/immunology , Cytokines/metabolism , Male , Inflammation/immunology , Interleukin-10/metabolism , Models, Theoretical , Infusions, Intravenous , Monocytes/immunology , Monocytes/drug effects , Interleukin-8/metabolism , Tumor Necrosis Factor-alpha/metabolism , Adult , Female , Lipopolysaccharides/administration & dosageABSTRACT
Lipopolysaccharide (LPS), an endotoxin, induces systemic inflammation by injection and is thought to be a causative agent of chronic inflammatory diseases, including type 2 diabetes mellitus (T2DM). However, our previous studies found that oral LPS administration does not exacerbate T2DM conditions in KK/Ay mice, which is the opposite of the response from LPS injection. Therefore, this study aims to confirm that oral LPS administration does not aggravate T2DM and to investigate the possible mechanisms. In this study, KK/Ay mice with T2DM were orally administered LPS (1 mg/kg BW/day) for 8 weeks, and blood glucose parameters before and after oral administration were compared. Abnormal glucose tolerance, insulin resistance progression, and progression of T2DM symptoms were suppressed by oral LPS administration. Furthermore, the expressions of factors involved in insulin signaling, such as insulin receptor, insulin receptor substrate 1, thymoma viral proto-oncogene, and glucose transporter type 4, were upregulated in the adipose tissues of KK/Ay mice, where this effect was observed. For the first time, oral LPS administration induces the expression of adiponectin in adipose tissues, which is involved in the increased expression of these molecules. Briefly, oral LPS administration may prevent T2DM by inducing an increase in the expressions of insulin signaling-related factors based on adiponectin production in adipose tissues.
Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Lipopolysaccharides , Animals , Mice , Adiponectin/metabolism , Administration, Oral , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/therapy , Insulin/metabolism , Insulin Resistance/physiology , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/pharmacology , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/therapyABSTRACT
LPS induces inflammatory cytokines, including IL-1ß, IL-6, and TNF-α, and causes an inflammatory response. The development of small molecules that have suppressive effect on those inflammatory cytokines is a desirable strategy for the treatment of inflammatory diseases. We synthesized 12 novel compounds with 4-amino-N-(4-(benzo[d]oxazol-2-ylamino)phenyl)butanamide moiety and evaluated their biological activities. Among them, 4 compounds (compound 5d, 5c, 5f, 5m and synthetic intermediate 4d) showed potent inhibition activities on IL-1ß and IL-6 mRNA expression in vitro. Further, in vivo activity was evaluated with two compounds (5f and 4d) and mRNA levels of IL-1ß, IL-6, and TNF-α were significantly decreased without hepatotoxicity. From the in vivo and in vitro test results, we confirmed that our synthesized compounds are effective for suppression of representative inflammatory cytokines.
Subject(s)
Benzoxazoles , Inflammation , Interleukin-6 , RNA, Messenger , Tumor Necrosis Factor-alpha , Benzoxazoles/pharmacology , Cytokines/genetics , Cytokines/metabolism , Humans , Inflammation/drug therapy , Inflammation/genetics , Inflammation/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Lipopolysaccharides/administration & dosage , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolismABSTRACT
BAM15 (a mitochondrial uncoupling agent) was tested on cecal ligation and puncture (CLP) sepsis mice with in vitro experiments. BAM15 attenuated sepsis as indicated by survival, organ histology (kidneys and livers), spleen apoptosis (activated caspase 3), brain injury (SHIRPA score, serum s100ß, serum miR370-3p, brain miR370-3p, brain TNF-α, and apoptosis), systemic inflammation (cytokines, cell-free DNA, endotoxemia, and bacteremia), and blood-brain barrier (BBB) damage (Evan's blue dye and the presence of green fluorescent E. coli in brain after an oral administration). In parallel, brain miR arrays demonstrated miR370-3p at 24 h but not 120 h post-CLP, which was correlated with metabolic pathways. Either lipopolysaccharide (LPS) or TNF-α upregulated miR370-3p in PC12 (neuron cells). An activation by sepsis factors (LPS, TNF-α, or miR370-3p transfection) damaged mitochondria (fluorescent color staining) and reduced cell ATP, possibly through profound mitochondrial activity (extracellular flux analysis) that was attenuated by BAM15. In bone-marrow-derived macrophages, LPS caused mitochondrial injury, decreased cell ATP, enhanced glycolysis activity (extracellular flux analysis), and induced pro-inflammatory macrophages (iNOS and IL-1ß) which were neutralized by BAM15. In conclusion, BAM15 attenuated sepsis through decreased mitochondrial damage, reduced neuronal miR370-3p upregulation, and induced anti-inflammatory macrophages. BAM15 is proposed to be used as an adjuvant therapy against sepsis hyperinflammation.
Subject(s)
Brain Diseases , MicroRNAs , Sepsis , Adenosine Triphosphate/genetics , Adenosine Triphosphate/metabolism , Animals , Brain Diseases/genetics , Brain Diseases/metabolism , Lipopolysaccharides/administration & dosage , Male , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Mitochondria/genetics , Mitochondria/metabolism , Punctures , Sepsis/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolismABSTRACT
BACKGROUND: Long noncoding RNA (lncRNA)-regulated mechanism in acute lung injury (ALI) has attracted special interests in study researches. We planned to disclose whether KCNQ1 overlapping transcript 1 (Kcnq1ot1) is involved in ALI and its mechanism. METHODS: The lipopolysaccharide (LPS)-induced ALI model was established in mice. Kcnq1ot1, microRNA (miR)-7a-5p and Reticulon 3 (Rtn3) levels were measured in lung tissues of mice. The vector that changed Kcnq1ot1, miR-7a-5p and Rtn3 expression was injected into LPS-treated mice, and pathological damage, fibrosis, apoptosis and inflammatory response were subsequently examined in lung tissues. The relation between Kcnq1ot1 and miR-7a-5p, and that between miR-7a-5p and Rtn3 were identified. RESULTS: Kcnq1ot1 and Rtn3 expression increased while miR-7a-5p expression decreased in LPS-treated mice. Reduced Kcnq1ot1 or elevated miR-7a-5p alleviated pathological damage, fibrosis, apoptosis and inflammatory response in ALI mice, while overexpressed Rtn3 worsened ALI in mice. Downregulation of Rtn3 reversed the exacerbation of miR-7a-5p downregulation in ALI mice. Kcnq1ot1 competitively bound to miR-7a-5p and miR-7a-5p negatively mediated Rtn3 expression. CONCLUSION: Our experiments evidence that silencing Kcnq1ot1 upregulates miR-7a-5p to suppress Rtn3 expression, thereby diminishing LPS-induced ALI.
Subject(s)
Acute Lung Injury/genetics , MicroRNAs/genetics , RNA, Long Noncoding/physiology , Animals , Lipopolysaccharides/administration & dosage , Male , Mice , Mice, Inbred BALB CABSTRACT
High-fat diet (HFD) consumption has been related to metabolic alterations, such as obesity and cardiovascular problems, and has pronounced effects on brain plasticity and memory impairment. HFD exposure has a pro-inflammatory effect associated with microglial cell modifications in the hippocampus, a region involved in the working memory process. Immune tolerance can protect from inflammation in periphery induced by HFD consumption, when the immune response is desensitized in development period with lipopolysaccharide (LPS) exposure, maybe this previously state can change the course of the diseases associated to HFDs but is not known if can protect the hippocampus's inflammatory response. In the present study, male mice were injected with LPS (100 µg.kg-1 body weight) on postnatal day 3 and fed with HFD for 16 weeks after weaning. Ours results indicated that postnatal exposure to LPS in the early postnatal developmental stage combined with HFD consumption prevented glycemia, insulin, HOMA-IR, microglial process, and increased pro-inflammatory cytokines mRNA expression, without changes in body weight gain and spatial working memory with respect vehicle + HFD group. These findings suggest that HFD consumption after postnatal LPS exposure induces hippocampal immune tolerance, without prevention in spatial working memory impairment on male mice.
Subject(s)
Diet, High-Fat , Hippocampus/immunology , Immune Tolerance , Lipopolysaccharides/pharmacology , Memory Disorders/immunology , Animals , Animals, Newborn , Lipopolysaccharides/administration & dosage , Male , Memory, Short-Term/physiology , Mice , Mice, Inbred C57BL , Spatial Memory/physiologyABSTRACT
The NKCC1 ion transporter contributes to the pathophysiology of common neurological disorders, but its function in microglia, the main inflammatory cells of the brain, has remained unclear to date. Therefore, we generated a novel transgenic mouse line in which microglial NKCC1 was deleted. We show that microglial NKCC1 shapes both baseline and reactive microglia morphology, process recruitment to the site of injury, and adaptation to changes in cellular volume in a cell-autonomous manner via regulating membrane conductance. In addition, microglial NKCC1 deficiency results in NLRP3 inflammasome priming and increased production of interleukin-1ß (IL-1ß), rendering microglia prone to exaggerated inflammatory responses. In line with this, central (intracortical) administration of the NKCC1 blocker, bumetanide, potentiated intracortical lipopolysaccharide (LPS)-induced cytokine levels. In contrast, systemic bumetanide application decreased inflammation in the brain. Microglial NKCC1 KO animals exposed to experimental stroke showed significantly increased brain injury, inflammation, cerebral edema and worse neurological outcome. Thus, NKCC1 emerges as an important player in controlling microglial ion homeostasis and inflammatory responses through which microglia modulate brain injury. The contribution of microglia to central NKCC1 actions is likely to be relevant for common neurological disorders.
Subject(s)
Brain Edema/genetics , Brain Injuries/genetics , Microglia/metabolism , Solute Carrier Family 12, Member 2/genetics , Stroke/genetics , Animals , Brain Edema/chemically induced , Brain Edema/metabolism , Brain Edema/pathology , Brain Injuries/chemically induced , Brain Injuries/metabolism , Brain Injuries/pathology , Bumetanide/pharmacology , Embryo, Mammalian , Gene Expression Regulation , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Inflammasomes/drug effects , Inflammasomes/metabolism , Inflammation , Injections, Intraventricular , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Lipopolysaccharides/administration & dosage , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Microglia/drug effects , Microglia/pathology , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Neural Stem Cells/drug effects , Neural Stem Cells/metabolism , Neural Stem Cells/pathology , Phenotype , Solute Carrier Family 12, Member 2/deficiency , Stroke/chemically induced , Stroke/metabolism , Stroke/pathologyABSTRACT
Anxiety is a common psychological disease which can induce severe social burdens. Searching methods that prevent the onset of anxiety is of great significance for ameliorating the social and individual problems induced by this type of disease. In this study, we investigated how innate immune pre-stimulation influences the anxiety-like behaviors in chronically stressed mice. Our results showed that a single injection of an innate immune stimulant lipopolysaccharide (LPS) at the dose of 50, 100, and 500 µg/kg 1 day before stress exposure prevented chronic social defeat stress (CSDS)-induced anxiety-like behaviors in mice. A single injection of LPS (100 µg/kg) 5 days before stress exposure produced similar preventive effects on CSDS-induced anxiety-like behaviors, while similar effects were not observed at the condition of 10-days interval between LPS injection and stress exposure. A second LPS injection 10 days after the first LPS injection or a 4 × LPS injection 10 days before stress exposure also prevented CSDS-induced anxiety-like behaviors. Moreover, a single injection of LPS (100 µg/kg) 1 day before stress exposure prevented the production of pro-inflammatory cytokines in the hippocampus and prefrontal cortex of CSDS mice. Suppression of innate immune stimulation by minocycline pretreatment simultaneously abrogated the preventive effect of LPS pre-injection (100 µg/kg) on CSDS-induced anxiety-like behaviors and pro-inflammatory cytokine production in the brain. Our results demonstrated that the pre-stimulation of the innate immune system can prevent the development of anxiety-like behaviors and the progression of the neuroinflammatory responses in the brain in chronically stressed mice.
Subject(s)
Anxiety/immunology , Anxiety/prevention & control , Hippocampus/immunology , Immunity, Innate/drug effects , Lipopolysaccharides/pharmacology , Prefrontal Cortex/immunology , Stress, Psychological , Animals , Anxiety/etiology , Behavior, Animal/drug effects , Behavior, Animal/physiology , Cytokines , Disease Models, Animal , Hippocampus/drug effects , Lipopolysaccharides/administration & dosage , Mice , Prefrontal Cortex/drug effects , Stress, Psychological/complications , Stress, Psychological/immunology , Stress, Psychological/prevention & controlABSTRACT
Emerging studies suggest that monocytes can be trained by bacterial endotoxin to adopt distinct memory states ranging from low-grade inflammation to immune exhaustion. While low-grade inflammation may contribute to the pathogenesis of chronic diseases, exhausted monocytes with pathogenic and immune-suppressive characteristics may underlie the pathogenesis of polymicrobial sepsis including COVID-19. However, detailed processes by which the dynamic adaption of monocytes occur remain poorly understood. Here we exposed murine bone-marrow derived monocytes to chronic lipopolysaccharide (LPS) stimulation at low-dose or high-dose, as well as a PBS control. The cells were profiled for genome-wide H3K27ac modification and gene expression. The gene expression of TRAM-deficient and IRAK-M-deficient monocytes with LPS exposure was also analyzed. We discover that low-grade inflammation preferentially utilizes the TRAM-dependent pathway of TLR4 signaling, and induces the expression of interferon response genes. In contrast, high dose LPS uniquely upregulates exhaustion signatures with metabolic and proliferative pathways. The extensive differences in the epigenomic landscape between low-dose and high-dose conditions suggest the importance of epigenetic regulations in driving differential responses. Our data provide potential targets for future mechanistic or therapeutic studies.
Subject(s)
Epigenomics , Inflammation/genetics , Lipopolysaccharides/pharmacology , Monocytes/drug effects , Transcriptome , Animals , COVID-19/virology , Dose-Response Relationship, Drug , Inflammation/immunology , Lipopolysaccharides/administration & dosage , Mice , SARS-CoV-2/isolation & purificationABSTRACT
Injury and dysfunction of endothelial cells (ECs) are closely related to the pathogenesis of steroid-induced osteonecrosis of the femoral head (ONFH), while MicroRNAs (miRNAs) play an essential role in the processes. Extracorporeal shockwave treatment (ESWT) has been used in the non-invasive treatment of various diseases including musculoskeletal and vascular disorders. In particular, ESWT with low energy levels showed a beneficial effect in ischemic tissues. However, there has been no comprehensive assessment of the effect of ESWT and miRNAs on steroid-induced ONFH. In the present study, we investigated the role and mechanism of ESWT and miRNAs both in vitro and in vivo. Using a steroid-induced ONFH rat model, we found that ESWT significantly enhances proliferation and angiogenesis as well as alleviates apoptosis. In two types of ECs, ESWT can promote cell proliferation and migration, enhance angiogenesis, and inhibit apoptosis. Notably, our study demonstrates that miR-135b is downregulated and modulated forkhead box protein O1 (FOXO1) in ECs treated with dexamethasone. Remarkably, both miR-135b knockdown and FOXO1 overexpression reversed the beneficial effect of ESWT on ECs. Additionally, our data suggest that ESWT activates the FOXO1-related pathway to impact proliferation, apoptosis, and angiogenesis. Taken together, this study indicates that ESWT relieves endothelial injury and dysfunction in steroid-induced ONFH via miR-135b targeting FOXO1.
Subject(s)
Extracorporeal Shockwave Therapy , Femur Head Necrosis/chemically induced , Femur Head Necrosis/therapy , Methylprednisolone/toxicity , MicroRNAs/metabolism , Nerve Tissue Proteins/metabolism , Angiogenesis Inducing Agents , Animals , Cell Proliferation , Cell Survival , Endothelial Cells/drug effects , Femur Head/pathology , Forkhead Box Protein O1/genetics , Forkhead Box Protein O1/metabolism , Gene Expression Regulation/drug effects , Glucocorticoids/administration & dosage , Glucocorticoids/toxicity , HEK293 Cells , Humans , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/toxicity , Male , Methylprednisolone/administration & dosage , MicroRNAs/genetics , Nerve Tissue Proteins/genetics , Random Allocation , RatsABSTRACT
Neuroinflammation has been implicated in cognitive dysfunction and the occurrence of depression in neurodegenerative diseases. Brain-derived neurotrophic factor (BDNF) is believed to be involved with the benefits of exercise training in boosting memory and learning processes and antidepressant therapies. This study aimed to investigate the effect of forced treadmill exercise on hippocampal BDNF expression levels, depression symptoms, tactile memory and working memory in lipopolysaccharide (LPS)-treated rats. For this purpose, 40 male Wistar rats received 0.25 mg/kg of LPS or saline intraperitoneally for 9 consecutive days before exercise. They again received a single injection of 0.5 mg/kg of LPS or saline on days 20 and 41 after exercise. Exercise groups had to run on a motorized treadmill 5 days a week for 8 weeks. Following the last exercise training session, forced swim test (FST), Y maze and novel object recognition (NOR) task were performed. Finally, the hippocampus of rats was removed and used for determination of BDNF expression levels by real-time polymerase chain reaction (real-time PCR). The data showed that LPS decreased BDNF expression levels, Y maze score, and recognition index in NOR and increased immobility time in FST (p < 0.05). In contrast, forced treadmill exercise increased BDNF expression levels and improved the percentage of spontaneous alternation, recognition index, and immobility time in LPS-treated rats (p < 0.05). There was a significant correlation between BDNF expression levels with immobility time and recognition index (p < 0.05) but not with the percentage of spontaneous alternation (p > 0.05). The findings suggest that forced treadmill exercise may protect the brain of LPS-treated rats by improving the symptoms of depression and cognitive function through its effect on BDNF expression levels.