Columbianadin suppresses glioblastoma progression by inhibiting the PI3K-Akt signaling pathway.

Glioblastoma (GBM) is the most common malignant glioma among brain tumors with low survival rate and high recurrence rate. Columbianadin (CBN) has pharmacological properties such as anti-inflammatory, analgesic, thrombogenesis-inhibiting and anti-tumor effects. However, it remains unknown that the effect of CBN on GBM cells and its underlying molecular mechanisms. In the present study, we found that CBN inhibited the growth and proliferation of GBM cells in a dose-dependent manner. Subsequently, we found that CBN arrested the cell cycle in G0/G1 phase and induced the apoptosis of GBM cells. In addition, CBN also inhibited the migration and invasion of GBM cells. Mechanistically, we chose network pharmacology approach by screening intersecting genes through targets of CBN in anti-GBM, performing PPI network construction followed by GO analysis and KEGG analysis to screen potential candidate signaling pathway, and found that phosphatidylinositol 3-kinase/Protein Kinase-B (PI3K/Akt) signaling pathway was a potential target signaling pathway of CBN in anti-GBM. As expected, CBN treatment indeed inhibited the PI3K/Akt signaling pathway in GBM cells. Furthermore, YS-49, an agonist of PI3K/Akt signaling, partially restored the anti-GBM effect of CBN. Finally, we found that CBN inhibited GBM growth in an orthotopic mouse model of GBM through inhibiting PI3K/Akt signaling pathway. Together, these results suggest that CBN has an anti-GBM effect by suppressing PI3K/Akt signaling pathway, and is a promising drug for treating GBM effectively.

Involvement of microglia-expressed MS4A6A in the onset of glioblastoma.

Glioblastoma multiforme (GBM) represents the deadliest form of brain tumour, characterized by its low survival rate and grim prognosis. Cytokines released from glioma-associated microglia/macrophages are involved in establishing the tumour microenvironment, thereby crucially promoting GBM progression. MS4A6A polymorphism was confirmed to be associated with neurodegenerative and polymorphism disease pathobiology, but whether it participates in the regulation of GBM and the underlying mechanisms is still not elucidated. Here, we found that MS4A6A was significantly upregulated in GBM patient samples. The results from the single-cell RNA-sequencing (scRNA-seq) database and immunostaining demonstrated the specific expression of MS4A6A in microglial cells. In vitro, microglial overexpression of MS4A6A stimulated the proliferation and migration of glioblastoma cells. Moreover, high MS4A6A mRNA expression was related to poor prognosis in GBM patients. Our study highlights the potential of MS4A6A as a promising biomarker for GBM, which may provide novel strategies for its prevention, diagnosis and treatment.

Erratum: ß-elemene promotes the senescence of glioma cells through regulating YAP-CDK6 signaling.

[This corrects the article on p. 370 in vol. 11, PMID: 33575077.].

Association between proliferative-to-secretory endometrial compaction and pregnancy outcomes after embryo transfer: a systematic review and meta-analysis.

STUDY QUESTION: Does the change in endometrial thickness (EMT) from the end of the follicular/estrogen phase to the day of embryo transfer (ET) determine subsequent pregnancy outcomes? SUMMARY ANSWER: Endometrial compaction from the late-proliferative to secretory phase is not associated with live birth rate (LBR) and other pregnancy outcomes. WHAT IS KNOWN ALREADY: Endometrial compaction has been suggested to be indicative of endometrial responsiveness to progesterone, and its association with ET outcome has been investigated but is controversial. STUDY DESIGN, SIZE, DURATION: A systematic review with meta-analysis was carried out. PubMed, EMBASE, and Web of Science were searched to identify relevant studies from inception to 18 November 2022. The reference lists of included studies were also manually screened for any additional publications. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cohort studies comparing ET pregnancy outcomes between patients with and without endometrial compaction were included. A review of the studies for inclusion, data extraction, and quality assessment was performed by two independent reviewers. The effect size was synthesized as odds ratio (OR) with 95% CI using a random-effects model. Heterogeneity and publication bias were assessed by the I2 statistic and Egger's test, respectively. The primary outcome was LBR. Secondary outcomes included biochemical pregnancy rate (BPR), clinical pregnancy rate (CPR), miscarriage rate (MR), ongoing pregnancy rate (OPR), and ectopic pregnancy rate (EPR). MAIN RESULTS AND THE ROLE OF CHANCE: Seventeen cohort studies involving 18 973 ET cycles fulfilled the eligibility criteria. The pooled results revealed that there were no significant differences between endometrial compaction and non-compaction groups in LBR (crude OR (cOR) = 0.95, 95% CI 0.87-1.04; I2 = 0%; adjusted OR (aOR) = 1.02, 95% CI 0.87-1.19, I2 = 79%), BPR (cOR = 0.93, 95% CI 0.81-1.06; I2 = 0%; aOR = 0.88, 95% CI 0.75-1.03, I2 = 0%), CPR (cOR = 0.98, 95% CI 0.81-1.18; I2 = 70%; aOR = 0.86, 95% CI 0.72-1.02, I2 = 13%), MR (cOR = 1.09, 95% CI 0.90-1.32; I2 = 0%; aOR = 0.91, 95% CI 0.64-1.31; I2 = 0%), and EPR (cOR = 0.70, 95% CI 0.31-1.61; I2 = 61%). The OPR was marginally higher in crude analysis (cOR = 1.48, 95% CI 1.01-2.16; I2 = 81%) among women with compacted endometrium, but was not evident in adjusted results (aOR = 1.36, 95% CI 0.86-2.14; I2 = 84%). Consistently, the pooled estimate of LBR remained comparable in further subgroup and sensitivity analyses according to the degree of compaction (0%, 5%, 10%, 15%, or 20%), type of ET (fresh, frozen, or euploid only), and endometrial preparation protocol (natural or artificial). No publication bias was observed based on Egger's test. LIMITATIONS, REASONS FOR CAUTION: Although the number of included studies is sufficient, data on certain measures, such as EPR, are limited. The inherent bias and residual confounding were also inevitable owing to the observational study design. Furthermore, inconsistent definitions of pregnancy outcomes may affect the accuracy of our pooled analysis. WIDER IMPLICATIONS OF THE FINDINGS: Given the lack of prognostic value, assessing endometrial compaction or repeated EMT measurement on the day of ET may not be necessary or warranted. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Natural Science Foundation of Jiangxi Province (20224BAB216025), National Natural Science Foundation of China (82260315), and Central Funds Guiding the Local Science and Technology Development (20221ZDG020071). The authors have no conflicts of interest to declare. REGISTRATION NUMBER: CRD42022384539 (PROSPERO).

Mapping trends and hotspots in research on global influenza vaccine hesitancy: A bibliometric analysis.

Background and Aims: Influenza is one of the most widespread respiratory infections and poses a huge burden on health care worldwide. Vaccination is key to preventing and controlling influenza. Influenza vaccine hesitancy is an important reason for the low vaccination rate. In 2019, Vaccine hesitancy was identified as one of the top 10 threats to global health by the World Health Organization. However, there remains a glaring scarcity of bibliometric research in that regard. This study sought to identify research hotspots and future development trends on influenza vaccine hesitation and provide a new perspective and reference for future research. Methods: We retrieved publications on global influenza vaccine hesitancy from the Web of Science Core Collection database, Scopus, and PubMed databases from inception to 2022. This study used VOSviewer and CiteSpace for visualization analysis. Results: Influenza vaccine hesitancy-related publications increased rapidly from 2012 and peaked in 2022. One hundred and nine countries contributed to influenza vaccine hesitation research, and the United States ranked first with 541 articles and 7161 citations. Vaccines-Basel was the journal with the largest number of published studies on influenza vaccine hesitations. MacDonald was the most frequently cited author. The most popular research topics on influenza vaccine hesitancy were (1) determinants of influenza vaccination in specific populations, such as healthcare workers, children, pregnant women, and so on; (2) influenza and COVID-19 vaccine hesitancy during the COVID-19 pandemic. Conclusions: The trend in the number of annual publications related to influenza vaccine hesitancy indicating the COVID-19 pandemic will prompt researchers to increase their attention to influenza vaccine hesitancy. With healthcare workers as the key, reducing vaccine hesitancy and improving vaccine acceptance in high-risk groups will be the research direction in the next few years.

Tenacissoside H repressed the progression of glioblastoma by inhibiting the PI3K/Akt/mTOR signaling pathway.

Glioblastoma (GBM) is one of the most common intracranial primary malignancies with the highest mortality rate, and there is a lack of effective treatments. In this study, we examined the anti-GBM activity of Tenacissoside H (TH), an active component isolated from the traditional Chinese medicine Marsdenia tenacissima (Roxb.) Wight & Arn (MT), and investigated the potential mechanism. Firstly, we found that TH decreased the viability of GBM cells by inducing cell cycle arrest and apoptosis, and inhibited the migration of GBM cells. Furthermore, combined with the Gene Expression Omnibus database (GEO) and network pharmacology as well as molecular docking, TH was shown to inhibit GBM progression by directly regulating the PI3K/Akt/mTOR pathway, which was further validated in vitro. In addition, the selective PI3K agonist 740 y-p partially restored the inhibitory effects of TH on GBM cells. Finally, TH inhibited GBM progression in an orthotopic transplantation model by inactivating the PI3K/Akt/mTOR pathway in vivo. Conclusively, our results suggest that TH represses GBM progression by inhibiting the PI3K/Akt/mTOR signaling pathway in vitro and in vivo, and provides new insight for the treatment of GBM patients.

pparß regulates lipid catabolism by mediating acox and cpt-1 genes in Scophthalmus maximus under heat stress.

Peroxisome proliferator-activated receptor ß (pparß) is a key gene-regulating lipid metabolism pathway, but its function in turbot remains unclear. In this study, the CDS of pparß was cloned from kidney for the first time. The CDS sequence length was 1533 bp encoding 510 amino acids. Structural analysis showed that the pparß protein contained a C4 zinc finger and HOLI domain, suggesting that the pparß gene of turbot has high homology with the PPAR gene of other species. The high expression patterns of pparß, acox, and cpt-1 at high temperatures, as shown through qPCR, indicated that high temperatures activated the transcriptional activity of pparß and increased the activity of the acox and cpt-1 genes. The expression of acox and cpt-1 was significantly inhibited when pparß was downregulated using RNAi technology and inhibitor treatments, suggesting that pparß positively regulated acox and cpt-1 expression at high temperatures and, thus, modulates lipid catabolism activity. These results demonstrate that pparß is involved in the regulation of lipid metabolism at high temperatures and expand a new perspective for studying the regulation of lipid metabolism in stress environments of teleost.

Pregnancy outcomes after frozen-thawed embryo transfer in women with COVID-19 history: A prospective cohort study.

The clinical effect of Coronavirus disease 2019 (COVID-19) on endometrial receptivity and embryo implantation remains unclear. Herein, we aim to investigate whether a COVID-19 history adversely affect female pregnancy outcomes after frozen-thawed embryo transfer (FET). This prospective cohort study enrolled 230 women who underwent FET cycles from December 2022 to April 2023 in an academic fertility center. Based on the history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection before FET, women were divided into the infected group (n = 136) and the control group (n = 94). The primary outcome was the clinical pregnancy rate per cycle. Multivariate logistic regression analysis was conducted to adjust for potential confounders, while subgroup analysis and restricted cubic splines were used to depict the effect of postinfection time interval on FET. The results showed that the clinical pregnancy rate was 59.6% in the infected group and 63.9% in the control group (p = 0.513). Similarly, the two groups were comparable in the rates of biochemical pregnancy (69.1% vs. 76.6%; p = 0.214) and embryo implantation (51.7% vs. 54.5%; p = 0.628). After adjustment, the nonsignificant association remained between prior infection and clinical pregnancy (OR = 0.78, 95% CI: 0.42-1.46). However, the odds for clinical pregnancy were significantly lower in the ≤30 days subgroup (OR = 0.15, 95% CI: 0.03-0.77), while no statistical significance was detected for 31-60 days and >60 days subgroups compared with the uninfected women. In conclusion, our findings suggested that SARS-CoV-2 infection in women had no significant effect on subsequent FET treatment overall, but pregnancy rates tended to be decreased if vitrified-thawed embryos were transferred within 30 days after infection. A 1-month postponement should be rationally recommended, while further studies with larger sample groups and longer follow-up periods are warranted for confirmation.

Chemotherapeutic drug elemene induces pain and anxiety-like behaviors by activating GABAergic neurons in the lateral septum of mice.

Most chemotherapeutic drugs are potent and have a very narrow range of dose safety and efficacy, most of which can cause many side effects. Chemotherapy-induced peripheral neuropathy (CIPN) is the most common and serious side effect of chemotherapy for cancer treatment. However, its mechanism of action is yet to be fully elucidated. In the present study, we found that the treatment of the chemotherapy drug elemene induced hyperalgesia accompanied by anxiety-like emotions in mice based on several pain behavioral assays, such as mechanical allodynia and thermal hyperalgesia tests. Second, immunostaining for c-fos (a marker of activated neurons) further showed that elemene treatment activated several brain regions, including the lateral septum (LS), cingulate cortex (ACC), paraventricular nucleus of the thalamus (PVT), and dorsomedial hypothalamic nucleus (DMH), most notably in the GABAergic neurons of the lateral septum (LS). Finally, we found that both chemogenetic inhibition and apoptosis of LS neurons significantly reduced pain- and anxiety-like behaviors in mice treated with elemene. Taken together, these findings suggest that LS is involved in the regulation of elemene-induced chemotherapy pain and anxiety-like behaviors, providing a new target for the treatment of chemotherapy pain induced by elemene.

SARM1 Promotes Neurodegeneration and Memory Impairment in Mouse Models of Alzheimer's Disease.

Neuroinflammation plays a crucial role in the pathogenesis and progression of Alzheimer's disease (AD). The Sterile Alpha and Toll Interleukin Receptor Motif-containing protein 1 (SARM1) has been shown to promote axonal degeneration and is involved in neuroinflammation. However, the role of SARM1 in AD remains unclear. In this study, we found that SARM1 was reduced in hippocampal neurons of AD model mice. Interestingly, conditional knockout (CKO) of SARM1 in the central nervous system (CNS, SARM1Nestin-CKO mice) delayed the cognitive decline in APP/PS1 AD model mice. Furthermore, SARM1 deletion reduced the Aß deposition and inflammatory infiltration in the hippocampus and inhibited neurodegeneration in APP/PS1 AD model mice. Further investigation into the underlying mechanisms revealed that the signaling of tumor necrosis factor-α (TNF-α) was downregulated in the hippocampus tissues of APP/PS1;SARM1Nestin-CKO mice, thereby alleviating the cognitive decline, Aß deposition and inflammatory infiltration. These findings identify unrecognized functions of SARM1 in promoting AD and reveal the SARM1-TNF-α pathway in AD model mice.

Dual targeting agent Thiotert inhibits the progression of glioblastoma by inducing ER stress-dependent autophagy.

Glioblastoma (GBM) is the most aggressive and lethal type of tumor in the central nervous system, characterized by a high incidence and poor prognosis. Thiotert, as a novel dual targeting agent, has potential inhibitory effects on various tumors. Here, we found that Thiotert effectively inhibited the proliferation of GBM cells by inducing G2/M cell cycle arrest and suppressed the migratory ability in vitro. Furthermore, Thiotert disrupted the thioredoxin (Trx) system while causing cellular DNA damage, which in turn caused endoplasmic reticulum (ER) stress-dependent autophagy. Knockdown of ER stress-related protein ATF4 in U251 cells inhibited ER stress-dependent autophagy caused by Thiotert to some extent. Orthotopic transplantation experiments further showed that Thiotert had the same anti-GBM activity and mechanism as in vitro. Conclusively, these results suggest that Thiotert induces ER stress-dependent autophagy in GBM cells by disrupting redox homeostasis and causing DNA damage, which provides new insight for the treatment of GBM.

A Y-shape connection device for pediatric patients with an indwelling catheter (Dia = 8Fr) during urodynamic studies, especially for filling phase measurements: a single-center prospective study for safety and effectiveness.

Introduction: This prospective study aimed to assess the effectiveness of a Y-shape connection device in reducing pain and bleeding in pediatric patients with indwelling catheters during urodynamic studies (UDS), while also obtaining effective results in the filling phase. Methods: A total of 45 pediatric patients with a mean age of 13 years were included, all of whom underwent both a UDS with the Y-shape connection device (Method A) and a standard UDS procedure (Method B). Results: The Y-shape connection device demonstrated similar overall urodynamic parameters compared to the standard procedure, while also resulting in significantly less bleeding (P = 0.006) and lower VAS scores during (1.12 ± 0.58 vs. 3.88 ± 1.01, P = 0.001) and after (0.12 ± 0.08 vs 2.91 ± 0.89, P = 0.001) the procedure. No adverse events were reported at the 1-month follow-up. Discussion: These findings suggest that the Y-shape connection device can effectively reduce pain and bleeding during and after UDS in pediatric patients with indwelling catheters (Dia = 8Fr), while also obtaining effective results in the filling phase. Therefore, this Y-shape connection device has a more significant value for children who require urodynamic studies and place more emphasis on filling phase parameters. Clinical trial registration: ChiCTR2300068280.

Targeting post-translational modifications of Foxp3: a new paradigm for regulatory T cell-specific therapy.

A healthy immune system is pivotal for the hosts to resist external pathogens and maintain homeostasis; however, the immunosuppressive tumor microenvironment (TME) damages the anti-tumor immunity and promotes tumor progression, invasion, and metastasis. Recently, many studies have found that Foxp3+ regulatory T (Treg) cells are the major immunosuppressive cells that facilitate the formation of TME by promoting the development of various tumor-associated cells and suppressing the activity of effector immune cells. Considering the role of Tregs in tumor progression, it is pivotal to identify new therapeutic drugs to target and deplete Tregs in tumors. Although several studies have developed strategies for targeted deletion of Treg to reduce the TME and support the accumulation of effector T cells in tumors, Treg-targeted therapy systematically affects the Treg population and may lead to the progression of autoimmune diseases. It has been understood that, nevertheless, in disease conditions, Foxp3 undergoes several definite post-translational modifications (PTMs), including acetylation, glycosylation, phosphorylation, ubiquitylation, and methylation. These PTMs not only elevate or mitigate the transcriptional activity of Foxp3 but also affect the stability and immunosuppressive function of Tregs. Various studies have shown that pharmacological targeting of enzymes involved in PTMs can significantly influence the PTMs of Foxp3; thus, it may influence the progression of cancers and/or autoimmune diseases. Overall, this review will help researchers to understand the advances in the immune-suppressive mechanisms of Tregs, the post-translational regulations of Foxp3, and the potential therapeutic targets and strategies to target the Tregs in TME to improve anti-tumor immunity.

Ultrasound-triggered release of miR-199a-3p from liposome nanobubbles for enhanced hepatocellular carcinoma treatment.

This study was aimed to develop an efficient tumour-targeted liposome nanobubbles (LNBs) system using ultrasound-targeted nanobubble destruction for enhanced release and transfection of miRNA-199a-3p in hepatocellular carcinoma (HCC) therapy. The prepared LNBs comprised a polyethylene glycol-modified liposome shell and a perfluoropentane (PFP) core. MiRNA-199a-3p was attached to the nanocomposite surface via electrostatic adsorption, while RGD peptide functionalized the LNBs surface for enhanced HCC cell targeting, namely PFP@miR-RGD-LNBs. The LNBs were spherical with a narrow size distribution. The gene-loaded LNBs effectively condensed miR-199a-3p and protected it from enzymatic degradation. Low-intensity focused ultrasound (LIFU) promoted a fast release of miR-199a-3p from the prepared LNBs, thereby enhancing therapeutic effects. The combined application of PFP@miR-RGD-LNBs and LIFU exhibited a more potent inhibitory effect on HepG2 cells than the other groups, potentially due to LIFU promoting rapid and efficient gene release at the target site and increasing cell membrane permeability. Quantitative reverse transcription-polymerase chain reaction analysis revealed significantly increased mRNA expression levels of key apoptosis markers (Bad, Bax, Caspase-9 and Caspase-3) in the PFP@miR-RGD-LNBs + LIFU group compared to other groups. These findings suggest that the prepared LNBs are highly likely to be promising candidates for further exploration of HCC gene delivery and therapy.

Research on the effectiveness and safety of bronchial thermoplasty in patients with chronic obstructive pulmonary disease.

OBJECTIVES: To investigate the clinical efficacy and safety of bronchial thermoplasty (BT) in treating patients with chronic obstructive pulmonary disease (COPD). METHODS: Clinical data of 57 COPD patients were randomized into the control (n = 29, conventional inhalation therapy) or intervention group (n = 28, conventional inhalation therapy plus BT). Primary outcomes were differences in clinical symptom changes, pulmonary function-related indicators, modified Medical Research Council (mMRC), 6-min walk test (6MWT), COPD assessment test (CAT) score and acute exacerbation incidence from baseline to an average of 3 and 12 months. Safety was assessed by adverse events. RESULTS: FEV1, FEV1(%, predicted) and FVC in both groups improved to varying degrees post-treatment compared with those pre-treatment (P < 0.05). The Intervention group showed greater improving amplitudes of FEV1 (Ftime × between groups = 21.713, P < 0.001) and FEV1(%, predicted) (Ftime × between groups = 31.216, P < 0.001) than the control group, and there was no significant difference in FVC variation trend (Ftime × between groups = 1.705, P = 0.193). mMRC, 6MWT and CAT scores of both groups post-treatment improved to varying degrees (Ps < 0.05), but the improving amplitudes of mMRC (Ftime × between groups = 3.947, P = 0.025), 6MWT (Ftime × between groups = 16.988, P < 0.001) and CAT score (Ftime × between groups = 16.741, P < 0.001) in the intervention group were greater than the control group. According to risk assessment of COPD acute exacerbation, the proportion of high-risk COPD patients with acute exacerbation in the control and intervention groups at 1 year post-treatment (100% vs 65%, 100% vs 28.6%), inpatient proportion (100% vs 62.1%; 100% vs 28.6%), COPD acute exacerbations [3.0 (2.50, 5.0) vs 1.0 (1.0, 2.50); 3.0(3.0, 4.0) vs 0 (0, 1.0)] and hospitalizations [2.0 (2.0, 3.0) vs 1.0 (0, 2.0); 2.0 (2.0, 3.0) vs 0 (0, 1.0)] were significantly lower than those pre-treatment (P < 0.05). Besides, data of the intervention group were significantly lower than the control group at each timepoint after treatment (P < 0.05). CONCLUSIONS: Combined BT therapy is superior to conventional medical treatment in improving lung function and quality of life of COPD patients, and it also significantly reduces the COPD exacerbation risk without causing serious adverse events.

TFEB: a double-edged sword for tumor metastasis.

Transcription factor EB, a member of the microphthalmia-associated transcription factor (MiTF/TFE) family, is a master regulator of autophagy, lysosome biogenesis, and TAMs. Metastasis is one of the main reasons for the failure of tumor therapy. Studies on the relationship between TFEB and tumor metastasis are contradictory. On the positive side, TFEB mainly affects tumor cell metastasis via five aspects, including autophagy, epithelial-mesenchymal transition (EMT), lysosomal biogenesis, lipid metabolism, and oncogenic signaling pathways; on the negative side, TFEB mainly affects tumor cell metastasis in two aspects, including tumor-associated macrophages (TAMs) and EMT. In this review, we described the detailed mechanism of TFEB-mediated regulation of metastasis. In addition, we also described the activation and inactivation of TFEB in several aspects, including the mTORC1 and Rag GTPase systems, ERK2, and AKT. However, the exact process by which TFEB regulates tumor metastasis remains unclear in some pathways, which requires further studies.

Prolonged Early Exposure to a High-Fat Diet Augments the Adverse Effects on Neurobehavior and Hippocampal Neuroplasticity: Involvement of Microglial Insulin Signaling.

High-fat diet (HFD) consumption may contribute to the high prevalence of cognitive-emotional issues in modern society. Mice fed a HFD for a prolonged period develop more severe neurobehavioral disturbances when first exposed to a HFD in the juvenile period than in adulthood, suggesting an initial age-related difference in the detrimental effects of long-term HFD feeding. However, the mechanism underlying this difference remains unclear. Here, male C57BL/6J mice initially aged 4 (IA4W) or 8 (IA8W) weeks were fed a control diet (CD) or HFD for 6 months and then subjected to metabolic, neurobehavioral, and histomorphological examinations. Although the detrimental effects of long-term HFD feeding on metabolism and neurobehavior were observed in mice of both ages, IA4W-HFD mice showed significant cognitive inflexibility accompanied by significantly greater levels of anxiety-like behavior than age-matched controls. Hippocampal neuroplasticity and microglial phenotype were altered by HFD feeding, whereas significant morphological alterations were more frequently observed in IA4W-HFD mice than in IA8W-HFD mice. Additionally, significantly increased hippocampal microglial engulfment of postsynaptic proteins and elevated phospho-insulin-receptor levels were observed in IA4W-HFD, but not in IA8W-HFD, mice. These findings suggest that aberrant microglia-related histomorphological changes in the hippocampus underlie the exacerbated detrimental neurobehavioral effects of prolonged early HFD exposure and indicate that enhanced insulin signaling might drive microglial dysfunction after prolonged early HFD exposure.