Maternal fiber-rich diet promotes early-life intestinal development in offspring through milk-derived extracellular vesicles carrying miR-146a-5p.

BACKGROUNDS: The intestinal development in early life is profoundly influenced by multiple biological components of breast milk, in which milk-derived extracellular vesicles (mEVs) contain a large amount of vertically transmitted signal from the mother. However, little is known about how maternal fiber-rich diet regulates offspring intestinal development by influencing the mEVs. RESULTS: In this study, we found that maternal resistant starch (RS) consumption during late gestation and lactation improved the growth and intestinal health of offspring. The mEVs in breast milk are the primary factor driving these beneficial effects, especially enhancing intestinal cell proliferation and migration. To be specific, administration of mEVs after maternal RS intake enhanced intestinal cell proliferation and migration in vivo (performed in mice model and indicated by intestinal histological observation, EdU assay, and the quantification of cyclin proteins) and in vitro (indicated by CCK8, MTT, EdU, and wound healing experiments). Noteworthily, miR-146a-5p was found to be highly expressed in the mEVs from maternal RS group, which also promotes intestinal cell proliferation in cells and mice models. Mechanically, miR-146a-5p target to silence the expression of ubiquitin ligase 3 gene NEDD4L, thereby inhibiting DVL2 ubiquitination, activating the Wnt pathway, and promoting intestinal development. CONCLUSION: These findings demonstrated the beneficial role of mEVs in the connection between maternal fiber rich diet and offspring intestinal growth. In addition, we identified a novel miRNA-146a-5p-NEDD4L-ß-catenin/Wnt signaling axis in regulating early intestinal development. This work provided a new perspective for studying the influence of maternal diet on offspring development.

Oral administration of sophoricoside (SOP) inhibits neuronal damage and neuroinflammation to curb neurodegeneration in Parkinson's disease.

Neuronal apoptosis and neuroinflammation are key factors involved in the pathological changes of Parkinson's disease (PD). Sophoricoside (SOP) has shown anti-inflammatory and anti-apoptosis effects in various diseases. However, the role of SOP in PD has not been reported. In this experiment, we found that oral administration of SOP alleviated weight loss and motor symptoms in 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-injected mice. Further studies revealed that SOP inhibited inflammatory responses and neuronal apoptosis in the midbrain region of MPTP-injected mice. In vitro mechanistic study, we found that SOP exerts neuroprotective effects through a two-sided action. On the one hand, SOP inhibits Lipopolysaccharide (LPS)-induced inflammatory responses in microglia by inhibiting the Nuclear factor kappa-B(NF-κB) pathway. On the other hand, SOP inhibits 1-methyl-4-phenylpyridinium (MPP+)-induced neuronal apoptosis by regulating the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway. Thus SOP is expected to be a potential therapeutic agent for PD by targeting neuroinflammation and neuronal apoptosis.

Notopterol inhibits LPS-induced inflammation in BV-2 cells via AKT/Nrf2/HO-1 signaling axis.

Accumulating research has indicated that inordinate activation of microglia releases inflammatory cytokines, damages neurons, and causes neuroinflammation, which eventually could lead to neurodegenerative diseases such as Parkinson's disease and Huntington's disease, etc. Notopterol (NOT) has anti-inflammatory and anti-oxidant functions in boundary tissues, but the effects of NOT on neuroinflammation have not been covered. Therefore, this study attempts to investigate the effect of NOT on neuroinflammation and the underlying mechanisms. According to the findings, NOT dramatically decreased the expression of pro-inflammatory mediators (interleukin-6 (IL-6), inducible nitric-oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), and Cyclooxygenase-2 (COX-2)) in LPS-exposed BV-2 cells. Western blot analysis revealed that NOT could promote the activation of AKT/Nrf2/HO-1 signaling pathway. Further studies have shown that anti-inflammatory property of NOT was inhibited by MK2206 (an AKT inhibitor), RA (an Nrf2 inhibitor), and SnPP IX (an HO-1 inhibitor). In addition, it was also discovered that NOT could weaken the damage of LPS to BV-2 cells and improve their survival rate. As a result, our results imply that NOT inhibits the inflammatory response of BV-2 cells through the AKT/Nrf2/HO-1 signaling axis and exerts a neuroprotective effect by inhibiting the activation of BV-2 cells.

α-Cyperone protects dopaminergic neurons and inhibits neuroinflammation in LPS-induced Parkinson's disease rat model via activating Nrf2/HO-1 and suppressing NF-κB signaling pathway.

Our previous study showed that α-Cyperone inhibited the inflammatory response triggered by activated microglia and protected dopaminergic neuron in in vitro cell model of Parkinson's disease (PD). It is unclear the effect of α-Cyperone in animal models of PD. In this study, our results indicated that α-Cyperone ameliorated motor dysfunction, protected dopaminergic neurons, and inhibited the reduction of dopamine and its metabolites in lipopolysaccharide (LPS)-induced PD rat model. Moreover, α-Cyperone suppressed the activation of microglia and the expression of neuroinflammatory factor (TNF-α, IL-6, IL-1ß, iNOS, COX-2 and ROS). Furthermore, the molecular mechanism research revealed that α-Cyperone inhibited neuroinflammation and oxidative stress to exert protective effect in microglia by activating Nrf2/HO-1 and suppressing NF-κB signaling pathway. Moreover, α-Cyperone upregulated the expression of antioxidant enzymes (GCLC, GCLM and NQO1) in microglia. In conclusion, our study demonstrates α-Cyperone alleviates dopaminergic neurodegeneration by inhibiting neuroinflammation and oxidative stress in LPS-induced PD rat model via activating Nrf2/HO-1 and suppressing NF-κB signaling pathway.

Effect of Palrnatine on lipopolysaccharide-induced acute lung injury by inhibiting activation of the Akt/NF|-κB pathway.

Inflammation plays an important role in the development of acute lung injury (ALI). Severe pulmonary inflammation can cause acute respiratory distress syndrome (ARDS) or even death. Expression of proinflammatory interleukin-|1ß (IL-|1ß) and inducible nitric oxide synthase (iNOS) in the process of pulmonary inflammation will further exacerbate the severity of ALI. The purpose of this study was to explore the effect of Palrnatine (Pa) on lipopolysaccharide (LPS)-induced mouse ALI and its underlying mechanism. Pa, a natural product, has a wide range of pharmacological activities with the potential to protect against lung injury. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) assays were performed to detect the expression and translation of inflammatory genes and proteins in vitro and in vivo. Immunoprecipitation was used to detect the degree of P65 translocation into the nucleus. We also used molecular modeling to further clarify the mechanism of action. The results showed that Pa pretreatment could significantly inhibit the expression and secretion of the inflammatory cytokine IL-1ß, and significantly reduce the protein level of the proinflammatory protease iNOS, in both in vivo and in vitro models induced by LPS. Further mechanism studies showed that Pa could significantly inhibit the activation of the protein kinase B (Akt)/nuclear factor-κB (NF-κB) signaling pathway in the LPS-induced ALI mode and in LPS-induced RAW264.7 cells. Through molecular dynamics simulation, we observed that Pa was bound to the catalytic pocket of Akt and effectively inhibited the biological activity of Akt. These results indicated that Pa significantly relieves LPS-induced ALI by activating the Akt/NF-κB signaling pathway.

Pedunculoside protects against LPS-induced mastitis in mice by inhibiting inflammation and maintaining the integrity of blood-milk barrier.

Mastitis is a disease that seriously threatens the health of the mammary gland after delivery. Pedunculoside (PE) is the main bioactive component of Aquifoliaceae. The purpose of this experiment is to explore the effects of PE on mastitis and its underlying mechanisms. Our research results showed that PE could significantly inhibit the increase in the levels of inflammatory mediators such as TNF-α, IL-6, IL-1ß, MPO and iNOS during mastitis. Mechanism studies have found that PE could significantly inhibit the phosphorylation of AKT protein and binds to the ASP-184 site. Further research found that PE also inhibited the activation of AKT's downstream pro-inflammatory signals NF-κB and MAPK. In addition, PE effectively promote the expression of tight junction proteins occludin and claudin-3 during inflammation, maintaining the integrity of the blood-milk barrier. In summary, our research shows that PE inhibits the phosphorylation of AKT/NF-κB and MAPK signals; It also relieves mastitis by repairing the blood-milk barrier.

Camptothecin Regulates Microglia Polarization and Exerts Neuroprotective Effects via Activating AKT/Nrf2/HO-1 and Inhibiting NF-κB Pathways In Vivo and In Vitro.

Microglia, the main immune cells in the brain, participate in the innate immune response in the central nervous system (CNS). Studies have shown that microglia can be polarized into pro-inflammatory M1 and anti-inflammatory M2 phenotypes. Accumulated evidence suggests that over-activated M1 microglia release pro-inflammatory mediators that damage neurons and lead to Parkinson's disease (PD). In contrast, M2 microglia release neuroprotective factors and exert the effects of neuroprotection. Camptothecin (CPT), an extract of the plant Camptotheca acuminate, has been reported to have anti-inflammation and antitumor effects. However, the effect of CPT on microglia polarization and microglia-mediated inflammation responses has not been reported. In our study we found that CPT improved motor performance of mice and reduced the loss of neurons in the substantia nigra (SN) of the midbrain in LPS-injected mice. In the mechanism study, we found that CPT inhibited M1 polarization of microglia and promotes M2 polarization via the AKT/Nrf2/HO-1 and NF-κB signals. Furthermore, CPT protected the neuroblastoma cell line SH-SY5Y and dopaminergic neuron cell line MN9D from damage mediated by microglia activation. In conclusion, our results demonstrate that CPT regulates the microglia polarization phenotype via activating AKT/Nrf2/HO-1 and inhibiting NF-κB pathways, inhibits neuro-inflammatory responses, and exerts neuroprotective effects in vivo and in vitro.

Echinocystic Acid Inhibits Inflammation and Exerts Neuroprotective Effects in MPTP-Induced Parkinson's Disease Model Mice.

Parkinson's disease (PD), the second primary neurodegenerative disease affecting human health, is mainly characterized by dopaminergic neuron damage in the midbrain and the clinical manifestation of movement disorders. Studies have shown that neuroinflammation plays an important role in the progression of PD. Excessively activated microglia produce several pro-inflammatory mediators, leading to damage to the surrounding neurons and finally inducing neurodegeneration. Echinocystic acid (EA) exhibits an anti-inflammatory effect in peripheral tissues. However, whether it inhibited neuroinflammation remains unclear. Therefore, the current study investigates the effect of EA on neuroinflammation and whether it can improve PD symptoms through inhibiting neuroinflammation. In our experiments, we discovered that EA inhibited the production of pro-inflammatory mediators in LPS-exposed BV2 cells. Further mechanism-related studies revealed that EA inhibited inflammation by activating PI3K/Akt and inhibiting NF-κB and MAPK signal pathways in LPS-induced BV2 cells. Research revealed that EA eases microglia-mediated neuron death in SN4741 and SHSY5Y cells. In in vivo studies, the results demonstrated that EA improves weight loss and behavioral impairment in MPTP-induced mice. Further studies have revealed that EA inhibited dopaminergic neuron damage and inflammation in the mice midbrain. In conclusion, our study demonstrated that EA inhibits neuroinflammation and exerts neuroprotective effects by activating PI3K/Akt and inhibiting NF-κB and MAPK signal pathways in vivo and in vitro.

Evodiamine Inhibits Lipopolysaccharide (LPS)-Induced Inflammation in BV-2 Cells via Regulating AKT/Nrf2-HO-1/NF-κB Signaling Axis.

Neuroinflammation is caused by excessive activation of microglia and plays an essential role in neurodegenerative diseases. After activation, microglia produce several kinds of inflammatory mediators, trigger an excessive inflammatory response, and ultimately destroy the surrounding neurons. Therefore, agents that inhibit neuroinflammation may be potential drug candidates for neurodegenerative diseases. Evodiamine (EV) has anti-inflammatory functions in peripheral tissues. However, whether EV exerts the same function in neuroinflammation is not known. In the present study, the aim was to explore whether EV attenuates microglial overactivation and therefore suppresses the development of neuroinflammation in lipopolysaccharide (LPS)-stimulated BV-2 cells. It was found that EV effectively inhibited expression of proinflammatory mediators (cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)) via AKT/Nrf2/HO-1 activation and suppressed NF-κB p65 phosphorylation. In addition, EV could suppress LPS-induced inflammatory response and loss of dopaminergic neuron in mouse mesencephalic neuron--glia cells. Hence, these findings demonstrate that EV suppresses neuroinflammation caused by overactivated microglia via regulating the AKT/Nrf2/HO-1/NF-κB signaling axis.

Beta-naphthoflavone inhibits LPS-induced inflammation in BV-2 cells via AKT/Nrf-2/HO-1-NF-κB signaling axis.

Numerous studies have shown that over-activation of microglia could cause neuroinflammation and release pro-inflammatory mediators, which could result in neurodegenerative diseases, like Parkinson's disease, Alzheimer's disease etc. Beta-naphthoflavone (BNF) has anti-oxidant and anti-inflammatory effects in borderline tissues, but BNF has not been reported the effect associated with neuroinflammation. Therefore, the purpose of this experiment is to inquiry the impact and mechanism of BNF on neuroinflammation. The results indicated that BNF significantly inhibited the production of pro-inflammatory mediators (inducible nitric-oxide synthase (iNOS), Cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α) andinterleukin-6 (IL-6)) in LPS-exposed BV-2 cells. Analysis of western blot results found that BNF accelerated the activation of AKT/Nrf-2/HO-1 signaling pathway and suppressed NF-κB pathway activation. Further study showed that BNF inhibited activation of NF-κB pathway via promoting HO-1, and SnPP IX (a HO-1 inhibitor) could inhibit anti-inflammatory function of BNF. We also found that BNF reduced the apoptosis rate of Human neuroblastoma cells (SHSY5Y) and mouse hippocampal neuron cell line (HT22) by inhibiting release of inflammatory mediators in LPS-exposed BV2 cells. In a word, our results suggested that BNF could inhibit inflammatory response via AKT/Nrf-2/HO-1-NF-κB signaling axis in BV-2 cells and exerts neuroprotective impact via inhibiting the activation of BV2 cells.

α-Cyperone Attenuates H2O2-Induced Oxidative Stress and Apoptosis in SH-SY5Y Cells via Activation of Nrf2.

α-Cyperone, extracted from Cyperus rotundus, has been reported to inhibit microglia-mediated neuroinflammation. Oxidative stress and apoptosis play crucial roles in the course of Parkinson's disease (PD). PD is a common neurodegenerative disease characterized by selective death of dopaminergic neurons. This study was designed to investigate the neuroprotective effects of α-cyperone against hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis in dopaminergic neuronal SH-SY5Y cells. Neurotoxicity was assessed by MTT assay and the measurement of lactic dehydrogenase (LDH) release. The level of reactive oxygen species (ROS) was measured by dichlorodihydrofluorescin diacetate (DCFH-DA) staining. The apoptosis of SH-SY5Y cells was evaluated by annexin-V-FITC staining. The translocation of NF-E2-related factor 2 (Nrf2) was determined by western blot and immunofluorescence staining. Western blot analysis was conducted to determine the expression level of cleaved-caspase-3, the pro-apoptotic factor Bax, and the anti-apoptotic factor, Bcl-2. The results showed that α-cyperone substantially decreased H2O2-induced death, release of LDH, and the production of ROS in SH-SY5Y cells. In addition, we found that α-cyperone attenuated H2O2-induced cellular apoptosis. Moreover, α-cyperone remarkably reduced the expression of cleaved-caspase-3 and Bax, and upregulated Bcl-2. Furthermore, α-cyperone enhanced the nuclear translocation of Nrf2. Pretreatment with brusatol (BT, an Nrf2 inhibitor) attenuated α-cyperone-mediated suppression of ROS, cleaved-caspase-3, and Bax, as well as α-cyperone-induced Bcl-2 upregulation in H2O2-treated SH-SY5Y cells. α-cyperone neuroprotection required Nrf2 activation. In conclusion, α-cyperone attenuated H2O2-induced oxidative stress and apoptosis in SH-SY5Y cells via the activation of Nrf2, suggesting the potential of this compound in the prevention and treatment of PD.

Corrigendum: Isovitexin-Mediated Regulation of Microglial Polarization in Lipopolysaccharide-Induced Neuroinflammation via Activation of the CaMKKß/AMPK-PGC-1α Signaling Axis.

[This corrects the article DOI: 10.3389/fimmu.2019.02650.].

Isovitexin-Mediated Regulation of Microglial Polarization in Lipopolysaccharide-Induced Neuroinflammation via Activation of the CaMKKß/AMPK-PGC-1α Signaling Axis.

Microglia are the brain's immune cells and play an important role in regulating the microenvironment in the central nervous system. Activated microglia are capable of acquiring the pro-inflammatory (M1) phenotype and anti-inflammatory (M2) phenotype. Overactivation of microglia is neurotoxic and may lead to neuroinflammatory brain disorders. Neuroinflammation in the brain plays a crucial role part in the pathophysiology of many psychiatric and neurological diseases. The inhibition of M1 microglia and promotion of M2 microglia was demonstrated to treat and prevent these diseases through reduced neuroinflammation. Isovitexin (IVX) has anti-inflammatory properties and passes through the blood-brain barrier; however, the molecular mechanism that modulates IVX-mediated microglial polarization remains unclear. In BV-2 cells and mouse primary microglia, IVX suppressed the expression of M1 microglial markers, enhanced the expression of M2 microglial markers, and enhanced the release of interleukin 10 (IL-10). IVX promoted the expression of peroxisome proliferator-activated receptor-γ (PPARγ) and PPARγ coactivator-1α (PGC-1α) in LPS-induced microglial activation. The inhibition of PPARγ and PGC-1α attenuated the regulatory effect of IVX in LPS-induced microglial polarization. IVX increased the expression of p-CaMKKß, p-AMPK, and PGC-1α in BV-2 cells. Inhibition of CaMKKß with STO-609 or knockdown of CaMKKß with CaMKKß siRNA attenuated IVX-mediated M2 microglial polarization in LPS-treated cells. In LPS-treated mice, the inhibition of CaMKKß and PGC-1α attenuated the IVX-mediated prevention of sickness behavior and enhanction of IVX-mediated M2 microglial polarization. IVX promoted M2 microglial polarization which exerted anti-inflammatory effects on LPS-induced neuroinflammation via the activation of the CaMKKß/AMPK-PGC-1α signaling axis.

Farrerol protects dopaminergic neurons in a rat model of lipopolysaccharide-induced Parkinson's disease by suppressing the activation of the AKT and NF-κB signaling pathways.

Neuroinflammation, characterized by the activation of microglia, is one of the major pathologic processes of Parkinson's disease (PD). Overactivated microglia can release many pro-inflammatory cytokines, which cause an excessive inflammatory response and eventually damage dopaminergic neurons. Therefore, the inhibition of neuroinflammation that results from the overactivation of microglia may be an method for the treatment of PD. Farrerol is a 2,3-dihydro-flavonoid obtained from Rhododendron, and it possesses various biological functions, including anti-inflammatory, antibacterial and antioxidant activities. However, the effect of farrerol on neuroinflammation has not been investigated. The present study uncovered a neuroprotective role for farrerol. In vitro, farrerol markedly decreased the production of inflammatory mediators, including interleukin-6 (IL-6), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), cyclooxygenase 2 (COX-2) and induced nitric oxide synthase (iNOS), induced by lipopolysaccharide (LPS) in BV-2 cells. This anti-inflammatory effect was regulated via inhibiting NF-κB p65 and AKT phosphorylation. Furthermore, we found that farrerol alleviated microglial activation and dopaminergic neuronal death in rats with LPS-induced PD. Pretreatment with farrerol markedly improved motor deficits in rats with LPS-induced PD. Taken together, our results indicate that the neuroprotective effect of the farrerol, which prevents microglial overactivation in rats with LPS-induced PD, may provide a potential therapy for patients suffering from PD.

Myricetin relieves LPS-induced mastitis by inhibiting inflammatory response and repairing the blood-milk barrier.

Mastitis, an inflammation of mammary gland, is a serious disease that affects the health of dairy cows around the world. Myricetin, a flavonoid from Bayberry, has been reported to suppress various inflammatory response. The aim of this study was to evaluate the effect of myricetin on lipopolysaccharide (LPS)-induced in vivo and in vitro mastitis model and clarify the underlying mechanism. In vivo experiments, myricetin attenuated the severity of inflammatory lesion and neutrophil infiltration. Moreover, myricetin pretreatment induced a significant decrease in the activity of myeloperoxidase (MPO) and the production of TNF-α, IL-6, and IL-1ß triggered by LPS. Myricetin pretreatment could also increase the integrity of the blood-milk barrier and upregulate the tight junction proteins in LPS-induced mice mastitis. In vitro, myricetin inhibited LPS-induced inflammatory response in mice mammary epithelial cells (mMECs). In the further mechanism studies, we found that the anti-inflammatory effect of myricetin was mediated by inhibiting LPS-induced phosphorylation of AKT, IKK-α, IκB-α, and P65 in vivo and in vitro. Collectively, these data suggested that myricetin effectively ameliorated the inflammatory response by inhibiting the AKT/IKK/NF-κB signaling pathway and repairing the integrity of blood-milk barrier in LPS-induced mice mastitis.

Vanillin protects the blood-milk barrier and inhibits the inflammatory response in LPS-induced mastitis in mice.

Vanillin is used in a variety of food, chemical, and pharmaceutical applications, and exhibits anti-inflammatory properties. However, there are no reports about the effects of vanillin on lipopolysaccharide (LPS)-induced mastitis. In this study, we explored the effects of vanillin on the subsequent inflammatory response and blood-milk barrier in LPS-induced mastitis. Results showed that vanillin suppressed the inflammatory response by a) inhibiting myeloperoxidase activity; b) decreasing the production of pro-inflammatory mediators which include tumor necrosis factor alpha (Tnf-α; from 128.5 ±â€¯14.59 to 67.51 ±â€¯10.88,pg/mL, P < 0.01), interleukin-6 (Il-6; from 531.5 ±â€¯196.4 to 109.3 ±â€¯24.14, pg/mL, P < 0.05), interleukin-1ß (Il-1ß; from 2569 ±â€¯1648 to 731.8 ±â€¯171.7, pg/mL, P < 0.05), inducible nitric oxide synthase (Inos), and cyclooxygenase-2 (Cox-2); and c) repairing the blood-milk barrier by increasing the protein levels of the tight junction proteins, including zona occludens 1 (Zo-1), claudin-3, and occludin. In vitro experiment, Vanillin can inhibit LPS-induced inflammation and enhance the protein levels of tight junction proteins. Further studies have shown that vanillin inhibits inflammation by inhibiting mitogen-activated protein kinases (MAPKs) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathways. Our findings showed that vanillin protects mammary gland from LPS-induced mastitis by enhancing the blood-milk barrier and inhibiting the inflammatory response.

Polydatin Prevents Lipopolysaccharide (LPS)-Induced Parkinson's Disease via Regulation of the AKT/GSK3ß-Nrf2/NF-κB Signaling Axis.

Parkinson's disease (PD) is a common neurodegenerative disease characterized by selective loss of dopaminergic neurons in the substantia nigra (SN). Neuroinflammation induced by over-activation of microglia leads to the death of dopaminergic neurons in the pathogenesis of PD. Therefore, downregulation of microglial activation may aid in the treatment of PD. Polydatin (PLD) has been reported to pass through the blood-brain barrier and protect against motor degeneration in the SN. However, the molecular mechanisms underlying the effects of PLD in the treatment of PD remain unclear. The present study aimed to determine whether PLD protects against dopaminergic neurodegeneration by inhibiting the activation of microglia in a rat model of lipopolysaccharide (LPS)-induced PD. Our findings indicated that PLD treatment protected dopaminergic neurons and ameliorated motor dysfunction by inhibiting microglial activation and the release of pro-inflammatory mediators. Furthermore, PLD treatment significantly increased levels of p-AKT, p-GSK-3ßSer9, and Nrf2, and suppressed the activation of NF-κB in the SN of rats with LPS-induced PD. To further explore the neuroprotective mechanism of PLD, we investigated the effect of PLD on activated microglial BV-2 cells. Our findings indicated that PLD inhibited the production of pro-inflammatory mediators and the activation of NF-κB pathways in LPS-induced BV-2 cells. Moreover, our results indicated that PLD enhanced levels of p-AKT, p-GSK-3ßSer9, and Nrf2 in BV-2 cells. After BV-2 cells were pretreated with MK2206 (an inhibitor of AKT), NP-12 (an inhibitor of GSK-3ß), or Brusatol (BT; an inhibitor of Nrf2), treatment with PLD suppressed the activation of NF-κB signaling pathways and the release of pro-inflammatory mediators in activated BV-2 cells via activation of the AKT/GSK3ß-Nrf2 signaling axis. Taken together, our results are the first to demonstrate that PLD prevents dopaminergic neurodegeneration due to microglial activation via regulation of the AKT/GSK3ß-Nrf2/NF-κB signaling axis.

G Protein-Coupled Receptor 109A and Host Microbiota Modulate Intestinal Epithelial Integrity During Sepsis.

The intestinal epithelial barrier is important to mucosal immunity, although how it is maintained after damage is unclear. Here, we show that G protein-coupled receptor 109A (GPR109A) supports barrier integrity and decreases mortality in a mouse cecum ligation and puncture (CLP) sepsis model. Data from 16S RNA sequencing showed that the intestinal microbiota of WT and Gpr109a-/- mice clustered differently and their compositions were disrupted after CLP surgery. GPR109A-deficient mice showed increased mortality, intestinal permeability, altered inflammation, and lower tight junction gene expression. After eliminating the intestinal flora with antibiotics, all experimental mice died within 48 h of CLP surgery. This demonstrates the critical role of the gut microbiota in CLP-induced sepsis. Importantly, mortality and other pathologies in the model were decreased after Gpr109a-/- mice received WT gut microbiota. These findings indicate that GPR109A regulates the gut microbiota, contributing to intestinal epithelial barrier integrity and decreased mortality in CLP-induced sepsis.

Tubeimoside I Protects Dopaminergic Neurons Against Inflammation-Mediated Damage in Lipopolysaccharide (LPS)-Evoked Model of Parkinson's Disease in Rats.

Parkinson's disease (PD), a frequent degenerative disease in the elderly, is characterized by dopaminergic neurodegeneration in the substantia nigra pars compacta (SNpc). Neuroinflammation caused by over-activated microglia plays a crucial role in the pathogenesis of PD. Tubeimoside I (TBMS1) has a broad anti-inflammatory effect in peripheral tissues, but the effect on neuroinflammation has not been reported. Therefore, we explored whether TBMS1 could protect dopaminergic neurons by inhibiting the activation of microglia in lipopolysaccharide (LPS)-induced PD rat model. In addition, then, the effect and mechanism of TBMS1 on neuroinflammation were assessed in LPS-exposed murine microglial BV-2 cells. The results in vivo showed that TBMS1 suppressed microglial activation and dopaminergic neurons' reduction in LPS-injected PD rat model. In vitro study found that TBMS1 could inhibit LPS-induced inflammatory responses in BV-2 cells, and this effect was mediated by suppressing the phosphorylation of protein kinase B (AKT), nuclear factor-kappa B (NF-κB p65), p38 and extracellular regulated protein kinases (ERK1/2). Taken together, these results demonstrated for the first time that TBMS1 played a role in protecting dopaminergic neurons by inhibiting neuroinflammation mediated by microglia.