Tetramethylpyrazine attenuates endotoxin-induced retinal inflammation by inhibiting microglial activation via the TLR4/NF-κB signalling pathway

YY1 Lactylation Aggravates Autoimmune Uveitis by Enhancing Microglial Functions via Inflammatory Genes

Activated microglia in the retina are essential for the development of autoimmune uveitis. Yin-Yang 1 (YY1) is an important transcription factor that participates in multiple inflammatory and immune-mediated diseases. Here, an increased YY1 lactylation in retinal microglia within in the experimental autoimmune uveitis (EAU) group is observed. YY1 lactylation contributed to boosting microglial activation and promoting their proliferation and migration abilities. Inhibition of lactylation suppressed microglial activation and attenuated inflammation in EAU. Mechanistically, cleavage under targets & tagmentation （CUT&Tag） analysis revealed that YY1 lactylation promoted microglial activation by regulating the transcription of a set of inflammatory genes, including STAT3, CCL5, IRF1, IDO1, and SEMA4D. In addition, p300 is identified as the writer of YY1 lactylation. Inhibition of p300 decreased YY1 lactylation and suppressed microglial inflammation in vivo and in vitro. Collectively, the results showed that YY1 lactylation promoted microglial dysfunction in autoimmune uveitis by upregulating inflammatory cytokine secretion and boosting cell migration and proliferation. Therapeutic effects can be achieved by targeting the lactate/p300/YY1 lactylation/inflammatory genes axis.

Protective effect of Tetrandrine on optic nerve by inhibiting glial activation through NF-κB pathway

Introduction

This study aimed to explore the effect and molecular mechanism of Tetrandrine (Tet) onlipopolysaccharide (LPS)-induceduveitis andoptic nerve injury in vivo and in vitro.

Methods

Uveitis was induced by LPS injected into the hindlimb foot pad of Wistar rats and was intervened by retroeyeball injection of Tet (100 nM, 1 μM or 10 μM).The anterior segment inflammation was observed by slit lamp. Tunelassay was used to detect the survival state of ganglion cells and nuclear layers of inner and outer. The detection of characteristic markers in different activation states of glial cells were performed by qualitative and quantitative test of immunofluorescence and western blotting. Also, western blotting was used to detect the expression of inflammatory factors in retina and the activation of nuclear factor kappa B (NF-κB) signal pathway. Meanwhile, routine blood test and function of liver and renal were performed.

Results

The ciliary hyperemia was obvious, and the iris vessels were dilated and tortuous in rats with LPS-induced uveitis. Tet-pretreated obviously elieved these symptoms. In addition, the dilation and hyperemia in Tet group were alleviated compared with LPS group, and the inflammatory scores in Tetgroup were significantly lower than those of LPS group. TUNEL Staining showed that the number ofretinal ganglion cell (RGCs) in Tetgroup was slightly less than that in normal group, but significantly more than that in LPS group, and the cells arranged orderly. Besides, the number of apoptotic cells was significantly less than that in LPS group. Tet reduced LPS-activated gliocyte in a dose-dependent manner. Tumour necrosis factor alpha (TNF-α), interleukin (IL)-1β, interferon gamma (γ-IFN) and IL-2 in retina were increased by LPS but decreased significantly viaTet-pretreatment. Moreover, LPS activate NF-κB signal pathway, while Tet efficiently inhibited this effect.Furthermore, injection of Tet did not damage theroutineblood, liver and kidney.

Conclusions

Retrobulbar injection of Tet significantly alleviatedLPS-induced uveitisand optic nerve injuryof rats by activating gliocyte and NF-κB signaling pathway.

Understanding mechanistic aspect of the therapeutic role of herbal agents on neuroplasticity in cerebral ischemic-reperfusion injury

ETHNOPHARMACOLOGICAL RELEVANCE

Stroke is one of the leading causes of death and disability. The only FDA-approved therapy for treating stroke is tissue plasminogen activator (tPA), exhibiting a short therapeutic window. Due to this reason, only a small number of patients can be benefitted in this critical period. In addition, the use of endovascular interventions may reverse vessel occlusion more effectively and thus help further improve outcomes in experimental stroke. During recovery of blood flow after ischemia, patients experience cognitive, behavioral, affective, emotional, and electrophysiological changes. Therefore, it became the need for an hour to discover a novel strategy for managing stroke. The drug discovery process has focused on developing herbal medicines with neuroprotective effects via modulating neuroplasticity.

AIM OF THE STUDY

We gather and highlight the most essential traditional understanding of therapeutic plants and their efficacy in cerebral ischemia-reperfusion injury. In addition, we provide a concise summary and explanation of herbal drugs and their role in improving neuroplasticity. We review the pharmacological activity of polyherbal formulations produced from some of the most frequently referenced botanicals for the treatment of cerebral ischemia damage.

MATERIALS AND METHODS

A systematic literature review of bentham, scopus, pubmed, medline, and embase (elsevier) databases was carried out with the help of the keywords like neuroplasticity, herbal drugs, neural progenitor cells, neuroprotection, stem cells. The review was conducted using the above keywords to understand the therapeutic and mechanistic role of herbal neuroprotective agents on neuroplasticity in cerebral ischemic-reperfusion injury.

RESULTS

Neuroplasticity emerged as an alternative to improve recovery and management after cerebral ischemic reperfusion injury. Neuroplasticity is a physiological process throughout one's life in response to any stimuli and environment. Traditional herbal medicines have been established as an adjuvant to stroke therapy since they were used from ancient times and provided promising effects as an adjuvant to experimental stroke. The plants and phytochemicals such as Curcuma longa L., Moringa oliefera Lam, Panax ginseng C.A. Mey., and Rehmannia glutinosa (Gaertn.) DC., etc., have shown promising effects in improving neuroplasticity after experimental stroke. Such effects occur by modulation of various molecular signalling pathways, including PI3K/Akt, BDNF/CREB, JAK/STAT, HIF-1α/VEGF, etc. CONCLUSIONS: Here, we gave a perspective on plant species that have shown neuroprotective effects and can show promising results in promoting neuroplasticity with specific targets after cerebral ischemic reperfusion injury. In this review, we provide the complete detail of studies conducted on the role of herbal drugs in improving neuroplasticity and the signaling pathway involved in the recovery and management of experimental stroke.

AIBP: A New Safeguard against Glaucomatous Neuroinflammation

Glaucoma is a group of ocular diseases that cause irreversible blindness. It is characterized by multifactorial degeneration of the optic nerve axons and retinal ganglion cells (RGCs), resulting in the loss of vision. Major components of glaucoma pathogenesis include glia-driven neuroinflammation and impairment of mitochondrial dynamics and bioenergetics, leading to retinal neurodegeneration. In this review article, we summarize current evidence for the emerging role of apolipoprotein A-I binding protein (AIBP) as an important anti-inflammatory and neuroprotective factor in the retina. Due to its association with toll-like receptor 4 (TLR4), extracellular AIBP selectively removes excess cholesterol from the plasma membrane of inflammatory and activated cells. This results in the reduced expression of TLR4-associated, cholesterol-rich lipid rafts and the inhibition of downstream inflammatory signaling. Intracellular AIBP is localized to mitochondria and modulates mitophagy through the ubiquitination of mitofusins 1 and 2. Importantly, elevated intraocular pressure induces AIBP deficiency in mouse models and in human glaucomatous retina. AIBP deficiency leads to the activation of TLR4 in Müller glia, triggering mitochondrial dysfunction in both RGCs and Müller glia, and compromising visual function in a mouse model. Conversely, restoring AIBP expression in the retina reduces neuroinflammation, prevents RGCs death, and protects visual function. These results provide new insight into the mechanism of AIBP function in the retina and suggest a therapeutic potential for restoring retinal AIBP expression in the treatment of glaucoma.

mPEG-CS-modified flexible liposomes-reinforced thermosensitive sol-gel reversible hydrogels for ocular delivery of multiple drugs with enhanced synergism

Non-invasive drug delivery offers a safe treatment while improving patient compliance. However, due to the particular physiological structure of the ocular, long-term retention and sustained drug release of the drug delivery system is crucial. Herein, this study aimed to design mPEG-CS-modified flexible liposomes-reinforced thermosensitive sol-gel reversible hydrogels (mPEG-CS-FL-TSG) for the delivery of astragaloside IV (AS-IV) and tetramethylpyrazine (TMP) to treat age-related macular degeneration. In vitro biological properties of mPEG-CS-FL and mPEG-CS-FL-TSG showed that they could be successfully taken up by ARPE-19 cells, and the uptake rate of mPEG-CS-FL-TSG was higher. Not only that, the release rate of mPEG-CS-FL-TSG was slower. More significantly, the results showed that the cytotoxicity of mPEG-CS-FL-TSG was lower than that of mPEG-CS-FL. In vivo result revealed that the drug delivery system could prominently enhance the ocular bioavailability of AS-IV and TMP, which is the enhanced synergism of well-permeable liposome and slow-releasing hydrogel. In summary, the mPEG-CS-FL-TSG can compensate for the short retention time and sudden release of liposome, as well as the low drug penetration of hydrogel, in order to show great promise in the non-invasive delivery of multiple drugs for the treatment of posterior ocular diseases.

Relationship between Uveitis and the Differential Reactivity of Retinal Microglia

Uveitis, a complicated group of ocular inflammatory diseases, can be affected by massive pathogenic contributors such as infection, autoimmunity, and genetics. Although it is well known that many pathological changes, including disorders of the immune system and disruption of the blood-retinal barrier, count much in the onset and progression of uveitis, there is a paucity of safe and effective treatments, which has exceedingly hindered the appropriate treatment of uveitis. As innate immune cells in the retina, microglia occupy a salient position in retinal homeostasis. Many studies have reported the activation of microglia in uveitis and the mitigation of uveitis by interfering with microglial reactivity, which strongly implicates microglia as a therapeutic target. However, it has been increasingly recognized that microglia are a nonhomogeneous population under different physiological and pathological conditions, which makes it essential to thoroughly have knowledge of their specific characteristics. The paper outlines the various properties of activated microglia in uveitis, summarizes the connections between their polarization patterns and the manifestations of uveitis, and ultimately is intended to enhance the understanding of microglial versatility and expedite the exploration of promising strategies for visual protection.

Glutathione trisulfide prevents lipopolysaccharide-induced retinal inflammation via inhibition of proinflammatory cytokine production in glial cells

We aimed to investigate the impact of glutathione trisulfide (GSSSG) on lipopolysaccharide (LPS)-induced inflammation in retinal glia. Inflammatory responses in mouse-derived glial cells and Wistar rat retinas were stimulated with administration of LPS. Cell survival and proinflammatory cytokine production were examined using the Calcein-AM assay, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Retinal microglia were visualized with immunohistochemistry for Iba1. Administration of LPS (10 µg/mL) or GSSSG (less than 100 µM) did not affect survival of cultured primary Müller cells and established microglial cells (BV-2). RT-qPCR and ELISA indicated that GSSSG inhibited LPS-induced gene upregulation and protein secretion of proinflammatory cytokines in these glial cells and rat retinas. GSSSG inhibited LPS-induced activation of TGF-β-activated kinase 1 (TAK1), which is an upstream kinase of NF-κB, in BV-2 cells. Finally, in vivo experiments indicated that intravitreal administration of GSSSG but not its relative glutathione disulfide (GSSG) inhibited LPS (500 ng)-induced accumulation of Iba1-immunopositive microglia in rat retinas. Taken together, GSSSG has the potential to prevent pathogenesis of inflammation-associated ocular diseases by inhibiting proinflammatory cytokine expression in retinal glial cells.

Anti-inflammatory properties of antiangiogenic fucoidan in retinal pigment epithelium cells

Age-related macular degeneration (AMD) is a multifactorial disease in which angiogenesis, oxidative stress and inflammation are important contributing factors. In this study, we investigated the anti-inflammatory effects of a fucoidan from the brown algae Fucus vesiculosus (FV) in primary porcine RPE cells. Inflammation was induced by lipopolysaccharide (LPS), polyinosinic:polycytidylic acid (Poly I:C), Pam2CSK4 (Pam), or tumor necrosis factor alpha (TNF-α). Cell viability was tested with thiazolyl blue tetrazolium bromide (MTT) test, barrier function by measuring transepithelial electric resistance (TEER), interleukin 6 (IL-6) and interleukin 8 (IL-8) secretion in ELISA, retinal pigment epithelium-specific 65 kDa protein (RPE65) and protectin (CD59) expression in Western blot, gene expression with quantitative polymerase chain reaction (qPCR) (IL6, IL8, MERTK, PIK3CA), and phagocytotic activity in a microscopic assay. FV fucoidan did not influence RPE cell viability. FV fucoidan reduced the Poly I:C proinflammatory cytokine secretion of IL-6 and IL-8. In addition, it decreased the expression of IL-6 and IL-8 in RT-PCR. LPS and TNF-α reduced the expression of CD59 in Western blot, this reduction was lost under FV fucoidan treatment. Also, LPS and TNF-α reduced the expression of visual cycle protein RPE65, this reduction was again lost under FV fucoidan treatment. Furthermore, the significant reduction of barrier function after Poly I:C stimulation is ameliorated by FV fucoidan. Concerning phagocytosis, however, the inflammation-induced reduction was not improved by FV fucoidan. FV and proinflammatory milieu did not relevantly influence phagocytosis relevant gene expression either. In conclusion, we show that fucoidan from FV can reduce proinflammatory stimulation in RPE induced by toll-like receptor 3 (TLR-3) activation and is of high interest as a potential compound for early AMD treatment.

Tetramethylpyrazine Attenuates Cognitive Impairment Via Suppressing Oxidative Stress, Neuroinflammation, and Apoptosis in Type 2 Diabetic Rats

Cognitive dysfunction is an important complication observed in type 2 diabetes mellitus (T2DM) patients. Tetramethylpyrazine (TMP) is known to exhibit anti-diabetic and neuroprotective properties. Therefore, the present study aimed to investigate the possible therapeutic effects of TMP against type 2 diabetes-associated cognitive impairment in rats. High-fat diet (HFD) followed by a low dose of streptozotocin (35 mg/kg) was used to induce diabetes in Sprague-Dawley rats. TMP (20, 40, and 80 mg/kg) and Pioglitazone (10 mg/kg) were administered for 4 weeks. The Morris water maze (MWM) and novel objective recognition task (NOR) tests were used to assess memory function. Fasting blood glucose (FBG), lipid profile, HOMA-IR, glycosylated hemoglobin (HbA1c), and glucose tolerance were measured. Acetylcholinesterase (AChE) and choline acetytransferase (ChAT) activity, acetylcholine (ACh) levels, oxidative stress, apoptotic (Bcl-2, Bax, caspase-3), and inflammatory markers (TNF-α, IL-1β, and NF-kβ) were assessed. BDNF, p-AKT, and p-CREB levels were also measured. In the present work, we observed that treatment of diabetic rats with TMP alleviated learning and memory deficits, improved insulin sensitivity, and attenuated hyperglycemia and dyslipidemia. Furthermore, treatment with TMP increased BDNF, p-Akt, and p-CREB levels, normalized cholinergic dysfunction, and suppressed oxidative, inflammatory, and apoptotic markers in the hippocampus. Collectively, our results suggest that the TMP may be an effective neuroprotective agent in alleviating type 2 diabetes-associated cognitive deficits.

Ligustrazine alleviates psoriasis-like inflammation through inhibiting TRAF6/c-JUN/NFκB signaling pathway in keratinocyte

Ligusticum chuanxiong Hort (Ligusticum; Apiaceae) (accepted name, Ligusticum striatum DC, on "The Plant List" for the latest version) is a Chinese herbal medicine (CHM) which mainly distributed in Sichuan Basin, China. Chuanxiong is the dried rhizome of Ligusticum chuanxiong Hort. Ligustrazine, also known as tetramethylpyrazine (TMP), is a main active fraction of chuanxiong. The aim of this study was to clarify the underlying mechanisms by which TMP protect against psoriasis-like inflammation in keratinocytes. Here, we demonstrated that TMP alleviated the severity and PASI scores of IMQ-induced psoriasis-like skin lesion in vivo. For the histopathology level, TMP inhibited the over-proliferation of keratinocytes in the epidermis and the substantial immune cells influx in dermis. For the mechanism of the ability of TMP on regulating inflammation, we confirmed that TMP regulate the TRAF6/c-JUN/NFκB signaling pathway through analyzing the proteomics profiling and verifying the expression of TRAF6, pho-c-Jun, pho-NFκB, so that the downstream psoriasis-relevant genes transcribed by c-JUN or NFκB were down-regulated. Furthermore, we predicted TRAF6 as the potential binding point of TMP. Accordingly, our study demonstrated that TMP regulated psoriasis-like inflammation through inhibiting TRAF6/c-JUN/NFκB signaling pathway in keratinocytes, which potentially provides evidence of the mechanism of TMP in the treatment and prevention of psoriasis.

Icariin alleviates uveitis by targeting peroxiredoxin 3 to modulate retinal microglia M1/M2 phenotypic polarization

Uveitis causes blindness and critical visual impairment in people of all ages, and retinal microglia participate in uveitis progression. Unfortunately, effective treatment is deficient. Icariin (ICA) is a bioactive monomer derived from Epimedium. However, the role of ICA in uveitis remains elusive. Our study indicated that ICA alleviated intraocular inflammation in vivo. Further results showed the proinflammatory M1 microglia could be transferred to anti-inflammatory M2 microglia by ICA in the retina and HMC3 cells. However, the direct pharmacological target of ICA is unknown, to this end, proteome microarrays and molecular simulations were used to identify the molecular targets of ICA. Data showed that ICA binds to peroxiredoxin-3 (PRDX3), increasing PRDX3 protein expression in both a time- and a concentration-dependent manner and promoting the subsequent elimination of H₂O₂. In addition, GPX4/SLC7A11/ACSL4 pathways were activated accompanied by PRDX3 activation. Functional tests demonstrated that ICA-derived protection is afforded through targeting PRDX3. First, ICA-shifted microglial M1/M2 phenotypic polarization was no longer detected by blocking PRDX3 both in vivo and in vitro. Next, ICA-activated GPX4/SLC7A11/ACSL4 pathways and downregulated H₂O₂ production were also reversed via inhibiting PRDX3 both in vivo and in vitro. Finally, ICA-elicited positive effects on intraocular inflammation were eliminated in PRDX3-deficient retina from experimental autoimmune uveitis (EAU) mice. Taking together, ICA-derived PRDX3 activation has therapeutic potential for uveitis, which might be associated with modulating microglial M1/M2 phenotypic polarization.

Gut Microbiome in Retina Health: The Crucial Role of the Gut-Retina Axis

The term microbiome means not only a complex ecosystem of microbial species that colonize our body but also their genome and the surrounding environment in which they live. Recent studies support the existence of a gut-retina axis involved in the pathogenesis of several chronic progressive ocular diseases, including age-related macular disorders. This review aims to underline the importance of the gut microbiome in relation to ocular health. After briefly introducing the characteristics of the gut microbiome in terms of composition and functions, the role of gut microbiome dysbiosis, in the development or progression of retinal diseases, is highlighted, focusing on the relationship between gut microbiome composition and retinal health based on the recently investigated gut-retina axis.

MiR-182-5p/TLR4/NF-κB axis contributes to the protective effect of caffeic acid phenethyl ester against cadmium-induced spleen toxicity and associated damage in mice

Cadmium (Cd) is a toxic heavy metal pollutant that can be accumulated in organs including the spleen, thereby threatening human health. In this study, the effect of caffeic acid phenethyl ester (CAPE, a bioactive component of honeybee propolis) on CdCl2-induced spleen toxicity and underlying mechanisms were examined in mice. Histological examinations revealed that CAPE (10 μmol/kg/day b.w.) could mitigate spleen damage induced by CdCl2 (1.5 mg/kg/day b.w.) in mice. Compared to the mice treated only by CdCl2, CAPE administration increased the body weight while decreasing the spleen weight, spleen Cd content and spleen to body ratio of the CdCl2-treated mice. Western blot and ELISA tests revealed that CAPE suppressed CdCl2-induced inflammation (indicated by the decreases in the levels of inflammatory indictors). TUNEL and Western blot results showed that CAPE suppressed CdCl2-induced apoptosis through reducing the percentage of TUNEL-positive cells and regulating apoptosis factors. The antagonistic effect of CAPE against CdCl2-induced spleen toxicity was realized by increasing miR-182-5p expression to regulate the TLR4/NF-κB pathway. Therefore, CAPE could be a food-derived spleen protector to counteract Cd-induced spleen toxicity through alleviating apoptosis and inflammation via the miR-182-5p/TLR4/NF-κB axis.

Tetramethylpyrazine Alleviates Tight Junction Disruption of Bronchial Mucosal Epithelial Cells Caused by Interleukin-17 via Inhibiting Nuclear Factor-κB-p65/Tumor Necrosis Factor-α Signaling Pathway

Bronchial mucosal epithelial dysregulation and barrier disruption are involved in the initiation and development of acute lung injury (ALI). Some inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-17 (IL-17) contribute to the pathological changes of ALI. However, the roles and relationship between TNF-α and IL-17 during the disruption of bronchial epithelial tight junction remain unclear. Tetramethylpyrazine (TMP) is confirmed to have beneficial functions in hemostasis, inflammation, and cell growth. Here, we demonstrated the protective effects of TMP on bronchial mucosal epithelial injury induced by IL-17. We showed that IL-17 stimulation in vitro markedly reduced occludin and zonula occludens-1 (ZO-1) expression in bronchial mucosal epithelial cells via the nuclear factor-κB-p65/TNF-α signaling pathway, including NF-κB-p65-triggered TNF-α gene transcription and expression. TMP obviously rescued IL-17-induced occludin and ZO-1 downregulation. Mechanically, TMP substantially suppressed NF-κB-p65 activation and NF-κB-p65-induced TNF-α production in bronchial mucosal epithelial cells caused by IL-17. Taken together, this study indicates that TMP has a protective effect on bronchial mucosal epithelial cell injury due to IL-17 induction by inhibiting the NF-κB-p65/TNF-α signaling pathway.

Glial cells modulate retinal cell survival in rotenone-induced neural degeneration

Administration of the mitochondrial complex I inhibitor rotenone provides an excellent model to study the pathomechanism of oxidative stress-related neural degeneration diseases. In this study, we examined the glial roles in retinal cell survival and degeneration under the rotenone-induced oxidative stress condition. Mouse-derived Müller, microglial (BV-2), and dissociated retinal cells were used for in vitro experiments. Gene expression levels and cell viability were determined using quantitative reverse transcription-polymerase chain reaction and the alamarBlue assay, respectively. Conditioned media were prepared by stimulating glial cells with rotenone. Retinal ganglion cells (RGCs) and inner nuclear layer (INL) were visualized on rat retinal sections by immunohistochemistry and eosin/hematoxylin, respectively. Rotenone dose-dependently induced glial cell death. Treatment with rotenone or rotenone-stimulated glial cell-conditioned media altered gene expression of growth factors and inflammatory cytokines in glial cells. The viability of dissociated retinal cells significantly increased upon culturing in media conditioned with rotenone-stimulated or Müller cell-conditioned media-stimulated BV-2 cells. Furthermore, intravitreal neurotrophin-5 administration prevented the rotenone-induced reduction of RGC number and INL thickness in rats. Thus, glial cells exerted both positive and negative effects on retinal cell survival in rotenone-induced neural degeneration via altered expression of growth factors, especially upregulation of microglia-derived Ntf5, and proinflammatory cytokines.

Retinal microglia polarization in diabetic retinopathy

Microglia, the main immune cell of the central nervous system (CNS), categorized into M1-like phenotype and M2-like phenotype, play important roles in phagocytosis, cell migration, antigen presentation, and cytokine production. As a part of CNS, retinal microglial cells (RMC) play an important role in retinal diseases. Diabetic retinopathy (DR) is one of the most common complications of diabetes. Recent studies have demonstrated that DR is not only a microvascular disease but also retinal neurodegeneration. RMC was regarded as a central role in neurodegeneration and neuroinflammation. Therefore, in this review, we will discuss RMC polarization and its possible regulatory factors in early DR, which will provide new targets and insights for early intervention of DR.

Maternal immune activation induces sustained changes in fetal microglia motility

Maternal infection or inflammation causes abnormalities in brain development associated with subsequent cognitive impairment and in an increased susceptibility to schizophrenia and autism spectrum disorders. Maternal immune activation (MIA) and increases in serum cytokine levels mediates this association via effects on the fetal brain, and microglia can respond to maternal immune status, but consensus on how microglia may respond is lacking and no-one has yet examined if microglial process motility is impaired. In this study we investigated how MIA induced at two different gestational ages affected microglial properties at different developmental stages. Immune activation in mid-pregnancy increased IL-6 expression in embryonic microglia, but failed to cause any marked changes in morphology either at E18 or postnatally. In contrast MIA, particularly when induced earlier (at E12), caused sustained alterations in the patterns of microglial process motility and behavioral deficits. Our research has identified an important microglial property that is altered by MIA and which may contribute to the underlying pathophysiological mechanisms linking maternal immune status to subsequent risks for cognitive disease.