Novel, high accuracy models for hepatocellular carcinoma prediction based on longitudinal data and cell-free DNA signatures.

BACKGROUND & AIMS: Current hepatocellular carcinoma (HCC) risk scores do not reflect changes in HCC risk resulting from liver disease progression/regression over time. We aimed to develop and validate two novel prediction models using multivariate longitudinal data, with or without cell-free DNA (cfDNA) signatures. METHODS: A total of 13,728 patients from two nationwide multicenter prospective observational cohorts, the majority of whom had chronic hepatitis B, were enrolled. aMAP score, as one of the most promising HCC prediction models, was evaluated for each patient. Low-pass whole-genome sequencing was used to derive multi-modal cfDNA fragmentomics features. A longitudinal discriminant analysis algorithm was used to model longitudinal profiles of patient biomarkers and estimate the risk of HCC development. RESULTS: We developed and externally validated two novel HCC prediction models with a greater accuracy, termed aMAP-2 and aMAP-2 Plus scores. The aMAP-2 score, calculated with longitudinal data on the aMAP score and alpha-fetoprotein values during an up to 8-year follow-up, performed superbly in the training and external validation cohorts (AUC 0.83-0.84). The aMAP-2 score showed further improvement and accurately divided aMAP-defined high-risk patients into two groups with 5-year cumulative HCC incidences of 23.4% and 4.1%, respectively (p = 0.0065). The aMAP-2 Plus score, which incorporates cfDNA signatures (nucleosome, fragment and motif scores), optimized the prediction of HCC development, especially for patients with cirrhosis (AUC 0.85-0.89). Importantly, the stepwise approach (aMAP -> aMAP-2 -> aMAP-2 Plus) stratified patients with cirrhosis into two groups, comprising 90% and 10% of the cohort, with an annual HCC incidence of 0.8% and 12.5%, respectively (p <0.0001). CONCLUSIONS: aMAP-2 and aMAP-2 Plus scores are highly accurate in predicting HCC. The stepwise application of aMAP scores provides an improved enrichment strategy, identifying patients at a high risk of HCC, which could effectively guide individualized HCC surveillance. IMPACT AND IMPLICATIONS: In this multicenter nationwide cohort study, we developed and externally validated two novel hepatocellular carcinoma (HCC) risk prediction models (called aMAP-2 and aMAP-2 Plus scores), using longitudinal discriminant analysis algorithm and longitudinal data (i.e., aMAP and alpha-fetoprotein) with or without the addition of cell-free DNA signatures, based on 13,728 patients from 61 centers across mainland China. Our findings demonstrated that the performance of aMAP-2 and aMAP-2 Plus scores was markedly better than the original aMAP score, and any other existing HCC risk scores across all subsets, especially for patients with cirrhosis. More importantly, the stepwise application of aMAP scores (aMAP -> aMAP-2 -> aMAP-2 Plus) provides an improved enrichment strategy, identifying patients at high risk of HCC, which could effectively guide individualized HCC surveillance.

Aluminum hydroxide exposure induces neurodevelopmental impairment in hESC-derived cerebral organoids.

Aluminum (Al) has been classified as a cumulative environmental pollutant that endangers human health. There is increasing evidence to suggest the toxic effects of Al, but the specific action on human brain development remains unclear. Al hydroxide (Al(OH)3), the most common vaccine adjuvant, is the major source of Al and poses risks to the environment and early childhood neurodevelopment. In this study, we explored the neurotoxic effect of 5 µg/ml or 25 µg/ml Al(OH)3 for six days on neurogenesis by utilizing human cerebral organoids from human embryonic stem cells (hESCs). We found that early Al(OH)3 exposure in organoids caused a reduction in the size, deficits in basal neural progenitor cell (NPC) proliferation, and premature neuron differentiation in a time and dose-dependent manner. Transcriptomes analysis revealed a markedly altered Hippo-YAP1 signaling pathway in Al(OH)3 exposed cerebral organoid, uncovering a novel mechanism for Al(OH)3-induced detrimental to neurogenesis during human cortical development. We further identified that Al(OH)3 exposure at day 90 mainly decreased the production of outer radial glia-like cells(oRGs) but promoted NPC toward astrocyte differentiation. Taken together, we established a tractable experimental model to facilitate a better understanding of the impact and mechanism of Al(OH)3 exposure on human brain development.

Loss of liver X receptor ß in astrocytes leads to anxiety-like behaviors via regulating synaptic transmission in the medial prefrontal cortex in mice.

Astrocytes are integral components of synaptic transmission, and their dysfunction leads to neuropsychiatric disorders such as anxiety and depression. Liver X receptor ß (LXRß) is expressed in astrocytes, and LXRß global knockout mice shows impaired synaptic formation. In order to define the role of LXRß in astrocytes, we used a conditional Cre-loxP system to specifically remove LXRß from astrocytes. We found that this deletion caused anxiety-like but not depressive-like behaviors in adult male mice. This behavioral phenotype could be completely reproduced by selective deletion of LXRß in astrocytes in the medial prefrontal cortex (mPFC). Pyramidal neurons in layer V of mPFC are involved in mood behaviors. We found that there was an increased spontaneous excitatory synaptic transmission in layer V pyramidal neurons of the mPFC of these mice. This was concurrent with increased dendritic complexity, despite normal appearance and number of dendritic spines. In addition, gene ontology analysis of RNA sequencing revealed that deletion of astrocytic LXRß led to the enrichment of the process of synaptic transmission in mPFC. Finally, we also confirmed that renormalized excitatory synaptic transmission in layer V pyramidal neurons alleviated the anxiety in mice with astrocytic LXRß deletion in mPFC. Together, our findings reveal that astrocytic LXRß in mPFC is critical in the regulation of synaptic transmission, and this provides a potential new target for treatment of anxiety-like behavior.

Ahi1 regulates serotonin production by the GR/ERß/TPH2 pathway involving sexual differences in depressive behaviors.

BACKGROUND: Depression is one of the most common psychiatric diseases. The monoamine transmitter theory suggests that neurotransmitters are involved in the mechanism of depression; however, the regulation on serotonin production is still unclear. We previously showed that Ahi1 knockout (KO) mice exhibited depression-like behavior accompanied by a significant decrease in brain serotonin. METHODS: In the present study, western blot, gene knockdown, immunofluorescence, dual-luciferase reporter assay, and rescue assay were used to detect changes in the Ahi1/GR/ERß/TPH2 pathway in the brains of male stressed mice and male Ahi1 KO mice to explain the pathogenesis of depression-like behaviors. In addition, E2 levels in the blood and brain of male and female mice were measured to investigate the effect on the ERß/TPH2 pathway and to reveal the mechanisms for the phenomenon of gender differences in depression-like behaviors. RESULTS: We found that the serotonin-producing pathway-the ERß/TPH2 pathway was inhibited in male stressed mice and male Ahi1 KO mice. We further demonstrated that glucocorticoid receptor (GR) as a transcription factor bound to the promoter of ERß that contains glucocorticoid response elements and inhibited the transcription of ERß. Our recent study had indicated that Ahi1 regulates the nuclear translocation of GR upon stress, thus proposing the Ahi1/GR/ERß/TPH2 pathway for serotonin production. Interestingly, female Ahi1 KO mice did not exhibit depressive behaviors, indicating sexual differences in depressive behaviors compared with male mice. Furthermore, we found that serum 17ß-estradiol (E2) level was not changed in male and female mice; however, brain E2 level significantly decreased in male but not female Ahi1 KO mice. Further, ERß agonist LY-500307 increased TPH2 expression and 5-HT production. Therefore, both Ahi1 and E2 regulate the ERß/TPH2 pathway and involve sexual differences in brain serotonin production and depressive behaviors. CONCLUSIONS: In conclusion, although it is unclear how Ahi1 controls E2 secretion in the brain, our findings demonstrate that Ahi1 regulates serotonin production by the GR/ERß/TPH2 pathway in the brain and possibly involves the regulation on sex differences in depressive behaviors. Video Abstract.

Motor Function Deficits in the Estrogen Receptor Beta Knockout Mouse: Role on Excitatory Neurotransmission and Myelination in the Motor Cortex.

BACKGROUND: Male estrogen receptor beta (ERß) knockout (BERKO) mice display anxiety and aggression linked to, among others, altered serotonergic signaling in the basolateral amygdala and dorsal raphe, impaired cortical radial glia migration, and reduced GABAergic signaling. The effects on primary motor cortex (M1 cortex) and locomotor activity as a consequence of ERß loss have not been investigated. OBJECTIVE: The aim of this study was to determine whether locomotor activity is altered as a consequence of the changes in the M1 cortex. METHODS: The locomotor activity of male wild-type (WT) and BERKO mice was evaluated using the open-field and rotarod tests. Molecular changes in the M1 cortex were analyzed by RNA sequencing, electron microscopy, electrophysiology, and immunohistological techniques. In addition, we established oligodendrocyte (OL) cultures from WT and BERKO mouse embryonic stem cells to evaluate OL function. RESULTS: Locomotor profiling revealed that BERKO mice were more active than WT mice but had impaired motor coordination. Analysis of the M1 cortex pointed out differences in synapse function and myelination. There was a reduction in GABAergic signaling resulting in imbalanced excitatory and inhibitory neurotransmission as well as a defective OL differentiation accompanied by myelin defects. The effects of ERß loss on OL differentiation were confirmed in vitro. CONCLUSION: ERß is an important regulator of GABAergic interneurons and OL differentiation, which impacts on adult M1 cortex function and may be linked to increased locomotor activity and decreased motor coordination in BERKO mice.

Liver X receptor ß regulates the development of the dentate gyrus and autistic-like behavior in the mouse.

The dentate gyrus (DG) of the hippocampus is a laminated brain region in which neurogenesis begins during early embryonic development and continues until adulthood. Recent studies have implicated that defects in the neurogenesis of the DG seem to be involved in the genesis of autism spectrum disorders (ASD)-like behaviors. Liver X receptor ß (LXRß) has recently emerged as an important transcription factor involved in the development of laminated CNS structures, but little is known about its role in the development of the DG. Here, we show that deletion of the LXRß in mice causes hypoplasia in the DG, including abnormalities in the formation of progenitor cells and granule cell differentiation. We also found that expression of Notch1, a central mediator of progenitor cell self-renewal, is reduced in LXRß-null mice. In addition, LXRß deletion in mice results in autistic-like behaviors, including abnormal social interaction and repetitive behavior. These data reveal a central role for LXRß in orchestrating the timely differentiation of neural progenitor cells within the DG, thereby providing a likely explanation for its association with the genesis of autism-related behaviors in LXRß-deficient mice.

Quantifying and monitoring fibrosis in non-alcoholic fatty liver disease using dual-photon microscopy.

OBJECTIVE: Fibrosis stage is strongly associated with liver-related outcomes and is a key surrogate endpoint in drug trials for non-alcoholic steatohepatitis. Dual-photon microscopy allows automated quantification of fibrosis-related parameters (q-FPs) and may facilitate large-scale histological studies. We aim to validate the performance of q-FPs in a large histological cohort. DESIGN: 344 patients with non-alcoholic fatty liver disease (NAFLD) underwent 428 liver biopsies (240 had paired transient elastography examination). Fibrosis stage was scored using the NASH Clinical Research Network system, and q-FPs were measured by dual-photon microscopy using unstained slides. Patients were randomly assigned to the training and validation cohorts to test the performance of individual q-FPs and derive optimal cut-offs. RESULTS: Over 25 q-FPs had area under the receiver-operating characteristics curves >0.90 for different fibrosis stages. Among them, the perimeter of collagen fibres and number of long collagen fibres had the highest accuracy. At the best cut-offs, the two q-FPs had 88.3%-96.2% sensitivity and 78.1%-91.1% specificity for different fibrosis stages in the validation cohort. q-FPs and histological scoring had nearly identical correlations with liver stiffness measurement, suggesting that the accuracy of q-FPs approached that of histological assessment. Among patients with paired liver biopsies, changes in the same q-FPs were associated with changes in fibrosis stage. At a median follow-up of 5.6 years, baseline q-FPs predicted liver-related events. CONCLUSION: q-FP is highly accurate in the assessment of fibrosis in NAFLD patients. This automated platform can be used in future studies as objective and reliable evaluation of histological fibrosis.

The absence of oestrogen receptor beta disturbs collagen I type deposition during Achilles tendon healing by regulating the IRF5-CCL3 axis.

Achilles tendon healing (ATH) remains an unanswered question in the field of sports medicine because it does not produce tissue with homology to the previously uninjured tissue. Oestrogen receptor ß (ERß) is involved in the injury and repair processes of tendons. Our previous study confirmed that ERß plays a role in the early stage of ATH by affecting adipogenesis, but its role in extracellular matrix (ECM) remodelling is unknown. We established a 4-week Achilles tendon repair model to investigate the mechanism through which ERß affects ATH at the very beginning of ECM remodelling phase. In vitro studies were performed using tendon-derived stem cells (TDSCs) due to their promising role in tendon healing. Behavioural and biomechanical tests revealed that ERß-deficient mice exhibit weaker mobility and inferior biomechanical properties, and immunofluorescence staining and qRT-PCR showed that these mice exhibited an erroneous ECM composition, as mainly characterized by decreased collagen type I (Col I) deposition. The changes in gene expression profiles between ERß-knockout and WT mice at 1 week were analysed by RNA sequencing to identify factors affecting Col I deposition. The results highlighted the IRF5-CCL3 axis, and this finding was verified with CCL3-treated TDSCs. These findings revealed that ERß regulates Col I deposition during ATH via the IRF5-CCL3 axis.

Dexmedetomidine attenuates ethanol-induced inhibition of hippocampal neurogenesis in neonatal mice.

BACKGROUND/AIMS: Ethanol (EtOH) exposure during a period comparable to the third trimester in human results in obvious neurotoxicity in the developing hippocampus and persistent deficits in hippocampal neurogenesis. Dexmedetomidine (DEX), a highly selective α-2-adrenergic agonist has been demonstrated to restore the impaired neurogenesis and neuronal plasticity in the dentate gyrus (DG) that follows neurological insult. However, the protective roles of DEX in the EtOH-induced deficits of postnatal neurogenesis in the hippocampus are still unknown. METHODS: Mice were pretreated with DEX prior to EtOH exposure to determine its protective effects on impaired postnatal hippocampal neurogenesis. Six-day-old neonatal mice were treated with DEX (125 µg/kg) or saline, followed by EtOH at a total of 5 g/kg or an equivalent volume of saline on P7. Immunohistochemistry and immunofluorescence were used to evaluate the neurogenesis and activated microglia in the DG. Quantitative real time PCR (qRT-PCR) was utilized to assess the expression of inflammatory factors in the hippocampus. RESULTS: DEX pretreatment attenuated the inhibition of EtOH-mediated hippocampal neurogenesis and the reduction of hippocampal neural precursor cells (NPCs). We further confirmed that DEX pretreatment reversed the EtOH-induced microglia activation in the DG as well as the upregulation of the hippocampal TNFα, MCP-1, IL-6, and IL-1ß mRNA levels. CONCLUSION: Our findings indicate that DEX pretreatment protects against EtOH-mediated inhibition of hippocampal neurogenesis in postnatal mice and reverses EtOH-induced neuroinflammation via repressing microglia activation and the expression of inflammatory cytokines.

Absence of estrogen receptor beta leads to abnormal adipogenesis during early tendon healing by an up-regulation of PPARγ signalling.

Achilles tendon injury is one of the challenges of sports medicine, the aetiology of which remains unknown. For a long time, estrogen receptor ß (ERß) has been known as a regulating factor of the metabolism in many connective tissues, such as bone, muscle and cartilage, but little is known about its role in tendon. Recent studies have implicated ERß as involved in the process of tendon healing. Tendon-derived stem cells (TDSCs) are getting more and more attention in tendon physiological and pathological process. In this study, we investigated how ERß played a role in Achilles tendon healing. Achilles tendon injury model was established to analyse how ERß affected on healing process in vivo. Cell proliferation assay, Western blots, qRT-PCR and immunocytochemistry were performed to investigate the effect of ERß on TDSCs. Here, we showed that ERß deletion in mice resulted in inferior gross appearance, histological scores and, most importantly, increased accumulation of adipocytes during the early tendon healing which involved activation of peroxisome proliferator-activated receptor γ (PPARγ) signalling. Furthermore, in vitro results of ours confirmed that the abnormity might be the result of abnormal TDSC adipogenic differentiation which could be partially reversed by the treatment of ERß agonist LY3201. These data revealed a role of ERß in Achilles tendon healing for the first time, thereby providing a new target for clinical treatment of Achilles tendon injury.

Lactobacillus acidophilus Exerts Neuroprotective Effects in Mice with Traumatic Brain Injury.

BACKGROUND: Traumatic brain injury (TBI) causes dysbiosis and intestinal barrier disruption, which further exacerbate brain damage via an inflammatory pathway. Gut microbiota remodeling by Lactobacillus acidophilus (LA) is a potential intervention. OBJECTIVE: The aim of this study was to investigate the neuroprotective effects of LA in TBI and elucidated underlying mechanisms. METHODS: C57BL/6 male mice (aged 8-9 wk) were subjected to weight-drop impact and gavaged with saline (TBI + vehicle) or LA (1 × 1010 CFU) (TBI + LA) on the day of injury and each day after for 1, 3, or 7 d. The sham + vehicle mice underwent craniotomy without brain injury and were gavaged with saline. Sensorimotor functions were determined pre-TBI and 1, 3, and 7 d postinjury. Indexes of neuroinflammation, peripheral inflammation, and intestinal barrier function were measured on days 3 and 7. Microbiota composition was measured 3 d postinjury. The data were mainly analyzed by 2-factor ANOVA. RESULTS: Compared with sham + vehicle mice, the TBI + vehicle mice exhibited impairments in the neurological severity score (+692%, day 3; +600%, day 7) and rotarod test (-58%, day 3; -45%, day 7) (P < 0.05), which were rescued by LA. The numbers of microglia (total and activated) and astrocytes and concentrations of TNF-α and IL1-ß in the perilesional cortex were elevated in the TBI + vehicle mice on day 3 or 7 compared with sham + vehicle mice (P < 0.05) and were normalized by LA. Compared with sham + vehicle mice, the TBI + vehicle mice exhibited increased serum concentrations of endotoxin and TNF-α, and intestinal barrier permeability (D-lactate) on days 3 and 7 (P < 0.05), and these changes were alleviated by LA. Three days postinjury, the microbiota composition was disrupted in the TBI + vehicle mice compared with sham + vehicle mice (P < 0.05), which was restored by LA. CONCLUSION: Our results demonstrate that LA exerts neuroprotective effects that may be associated with gut microbiota remodeling in TBI mice.

Protective effects of resveratrol on the inhibition of hippocampal neurogenesis induced by ethanol during early postnatal life.

Ethanol (EtOH) exposure during early postnatal life triggers obvious neurotoxic effects on the developing hippocampus and results in long-term effects on hippocampal neurogenesis. Resveratrol (RSV) has been demonstrated to exert potential neuroprotective effects by promoting hippocampal neurogenesis. However, the effects of RSV on the EtOH-mediated impairment of hippocampal neurogenesis remain undetermined. Thus, mice were pretreated with RSV and were later exposed to EtOH to evaluate its protective effects on EtOH-mediated toxicity during hippocampal development. The results indicated that a brief exposure of EtOH on postnatal day 7 resulted in a significant impairment in hippocampal neurogenesis and a depletion of hippocampal neural precursor cells (NPCs). This effect was attenuated by pretreatment with RSV. Furthermore, EtOH exposure resulted in a reduction in spine density on the granular neurons of the dentate gyrus (DG), and the spines exhibited a less mature morphological phenotype characterized by a higher proportion of stubby spines and a lower proportion of mushroom spines. However, RSV treatment effectively reversed these responses. We further confirmed that RSV treatment reversed the EtOH-induced down-regulation of hippocampal pERK and Hes1 protein levels, which may be related to the proliferation and maintenance of NPCs. Furthermore, EtOH exposure in the C17.2 NPCs also diminished cell proliferation and activated apoptosis, which could be reversed by pretreatment of RSV. Overall, our results suggest that RSV pretreatment protects against EtOH-induced defects in neurogenesis in postnatal mice and may thus play a critical role in preventing EtOH-mediated toxicity in the developing hippocampus.

LXR agonist rescued the deficit in the proliferation of the cerebellar granule cells induced by dexamethasone.

Dexamethasone (DEX) exposure during early postnatal life produces permanent neuromotor and intellectual deficits and stunts cerebellar growth. The liver X receptor (LXR) plays important roles in CNS development. However, the effects of LXR on the DEX-mediated impairment of cerebellar development remain undetermined. Thus, mice were pretreated with LXR agonist TO901317 (TO) and were later exposed to DEX to evaluate its protective effects on DEX-mediated deficit during cerebellar development. The results showed that an acute exposure of DEX on postnatal day 7 resulted in a significant impairment in cerebellar development and decreased the proliferation of granule neuron precursors in the external granule layer of cerebellum. This effect was attenuated by pretreatment with TO. We further found that the decrease in the proliferation caused by DEX occurred via up-regulation of glucocorticoid receptor and p27kip1, which could be partially prevented by LXR agonist pretreatment. Overall, our results suggest that LXR agonist pretreatment could protect against DEX-induced deficits in cerebellar development in postnatal mice and may thus be perspective recruited to counteract such GC side effects.

Neuroprotective effect of memantine on the retinal ganglion cells of APPswe/PS1ΔE9 mice and its immunomodulatory mechanisms.

Besides the cognitive impairment and degeneration in the brain, vision dysfunction and retina damage are always prevalent in patients with Alzheimer's disease (AD). The uncompetitive antagonist of the N-methyl-d-aspartate receptor, memantine (MEM), has been proven to improve the cognition of patients with AD. However, limited information exists regarding the mechanism of neurodegeneration and the possible neuroprotective mechanisms of MEM on the retinas of patients with AD. In the present study, by using APPswe/PS1ΔE9 double transgenic (dtg) mice, we found that MEM rescued the loss of retinal ganglion cells (RGCs), as well as improved visual impairments, including improving the P50 component in pattern electroretinograms and the latency delay of the P2 component in flash visual evoked potentials of APPswe/PS1ΔE9 dtg mice. The activated microglia in the retinas of APPswe/PS1ΔE9 dtg mice were also inhibited by MEM. Additionally, the level of glutamine synthetase expressed by Müller cells within the RGC layer was upregulated in APPswe/PS1ΔE9 dtg mice, which was inhibited by MEM. Simultaneously, MEM also reduced the apoptosis of choline acetyl transferase-immunoreactive cholinergic amacrine cells within the RGC layer of AD mice. Moreover, the phosphorylation level of extracellular regulated protein kinases 1 and 2 was increased in APPswe/PS1ΔE9 dtg mice, which was blocked by MEM treatment. These findings suggest that MEM protects RGCs in the retinas of APPswe/PS1ΔE9 dtg mice by modulating the immune response of microglia and the adapted response of Müller cells, making MEM a potential ophthalmic treatment alternative in patients with AD.

Stem-cell challenges in the treatment of Alzheimer's disease: a long way from bench to bedside.

Alzheimer's disease (AD) is the most prevalent type of dementia, and its neuropathology is characterized by deposition of insoluble ß-amyloid peptides, intracellular neurofibrillary tangles, and the loss of diverse neurons. Current pharmacological treatments for AD relieve symptoms without affecting the major pathological characteristics of the disease. Therefore, it is essential to develop new and effective therapies. Stem-cell types include tissue-specific stem cells, such as neural stem cells and mesenchymal stem cells, embryonic stem cells derived from blastocysts, and induced pluripotent stem cells (iPSCs) reprogrammed from somatic cells. Recent preclinical evidence suggests that stem cells can be used to treat or model AD. The mechanisms of stem cell based therapies for AD include stem cell mediated neuroprotection and trophic actions, antiamyloidogenesis, beneficial immune modulation, and the replacement of the lost neurons. iPSCs have been recently used to model AD, investigate sporadic and familial AD pathogenesis, and screen for anti-AD drugs. Although considerable progress has been achieved, a series of challenges must be overcome before stem cell based cell therapies are used clinically for AD patients. This review highlights the recent experimental and preclinical progress of stem-cell therapies for AD, and discusses the translational challenges of their clinical application.

Liver X receptor activation protects against inflammation and enhances autophagy in myocardium of neonatal mouse challenged by lipopolysaccharides.

Liver X receptors (LXRs) has been emerged as negative regulators of cardiomyocytic inflammation. The cellular process of autophagy is believed to play a protective role in myocardium during the inflammatory status. In this study, we investigated the role of LXRs agonist TO901317 (TO) on lipopolysaccharides (LPS)-induced myocardial inflammation and autophagy. The results showed that TO pretreatment significantly reduced the LPS-induced infiltration of inflammatory cells, elevation of NF-κB protein, TNF-α, and IL-6 mRNA levels in the myocardium. Moreover, LPS stimulated autophagy in neonatal mice heart, and this effect was further enhanced by TO pretreatment as evidenced by increased LC3-II/GAPDH ratio increment. Furthermore, TUNEL assay revealed LPS stimulation also increased the number of apoptotic cells in the myocardium, and the increment was inhibited by TO pretreatment. Our findings suggested that attenuation of inflammation and apoptosis, and enhancement of autophagy by TO may contribute to the protection of myocardium under inflammatory condition.

Understanding the link between different types of maternal diabetes and the onset of autism spectrum disorders.

Autism spectrum disorders (ASD) encompass a collection of neurodevelopmental disorders that exhibit impaired social interactions and repetitive stereotypic behaviors. Although the exact cause of these disorders remains unknown, it is widely accepted that both genetic and environmental factors contribute to their onset and progression. Recent studies have highlighted the potential negative impact of maternal diabetes on embryonic neurodevelopment, suggesting that intrauterine hyperglycemia could pose an additional risk to early brain development and contribute to the development of ASD. This paper presents a comprehensive analysis of the current research on the relationship between various forms of maternal diabetes, such as type 1 diabetes mellitus, type 2 diabetes mellitus, and gestational diabetes mellitus, and the likelihood of ASD in offspring. The study elucidates the potential mechanisms through which maternal hyperglycemia affects fetal development, involving metabolic hormones, immune dysregulation, heightened oxidative stress, and epigenetic alterations. The findings of this review offer valuable insights for potential preventive measures and evidence-based interventions targeting ASD.

Effects of six teaching strategies on medical students: protocol for a systematic review and network meta-analysis.

INTRODUCTION: Mounting evidence has suggested that novel teaching strategies have a positive impact on the quality and efficiency of medical education. However, the comprehensive evidence about the superiority among various strategies is not clear. To address this issue, we aim to conduct a systematic review and network meta-analysis (NMA) to evaluate the effects of six main strategies on medical education, including case-based learning, problem-based learning, team-based learning, flipped classrooms, simulation-based education and bridge-in, objective, preassessment, participatory learning, postassessment and summary. METHODS AND ANALYSIS: A systematic search will be conducted in PubMed, Embase, Web of Science and the Cochrane Library, covering studies published from database inception to November 2023. Randomised controlled trials which evaluated the different teaching methods and meet the eligibility criteria will be included. The effectiveness of medical students' learning, which is evaluated by theoretical test score, experimental or practical test score, will be analysed as the primary outcomes. Besides, the secondary outcomes consist of learning satisfaction of students and formative evaluation score. The study selection and data extraction will be independently performed by two authors. The risk of bias in each study will be assessed using V.2 of the Cochrane risk-of-bias tool for randomised controlled trials. To compare the effects of six teaching strategies, pairwise meta-analysis and NMA will be performed using Rev Man, STATA and R software. Statistical analyses including homogeneity tests, sensitivity analysis, consistency tests, subgroup analysis, Egger's test and publication bias will also be completed. ETHICS AND DISSEMINATION: No formal research ethics approval is required because this study is a meta-analysis based on published studies. The results will be disseminated to a peer-reviewed journal for publication. PROTOCOL REGISTRATION NUMBER: CRD42023456050.

Mitochondrial transfer between BMSCs and Müller promotes mitochondrial fusion and suppresses gliosis in degenerative retina.

Mitochondrial dysfunction and Müller cells gliosis are significant pathological characteristics of retinal degeneration (RD) and causing blinding. Stem cell therapy is a promising treatment for RD, the recently accepted therapeutic mechanism is cell fusion induced materials transfer. However, whether materials including mitochondrial transfer between grafted stem cells and recipient's cells contribute to suppressing gliosis and mechanism are unclear. In present study, we demonstrated that bone marrow mesenchymal stem cells (BMSCs) transferred mitochondria to Müller cells by cell fusion and tunneling nanotubes. BMSCs-derived mitochondria (BMSCs-mito) were integrated into mitochondrial network of Müller cells, improving mitochondrial function, reducing oxidative stress and gliosis, which protected visual function partially in the degenerative rat retina. RNA sequencing analysis revealed that BMSCs-mito increased mitochondrial DNA (mtDNA) content and facilitated mitochondrial fusion in damaged Müller cells. It suggests that mitochondrial transfer from BMSCs remodels Müller cells metabolism and suppresses gliosis; thus, delaying the degenerative progression of RD.

Extracellular vesicles from organoid-derived human retinal progenitor cells prevent lipid overload-induced retinal pigment epithelium injury by regulating fatty acid metabolism.

Retinal degeneration (RD), a group of diseases leading to irreversible vision loss, is characterised by retinal pigment epithelium (RPE) or retinal neuron damage and loss. With fewer risks of immune rejection and tumorigenesis, stem cell-secreted extracellular vesicles (EVs) offer a new cell-free therapeutic paradigm for RD, which remains to be investigated. Human retinal organoid-derived retinal progenitor cells (hERO-RPCs) are an easily accessible and advanced cell source for RD treatment. However, hERO-RPCs-derived EVs require further characterisation. Here, we compared the characteristics of EVs from hERO-RPCs (hRPC-EVs) with those of human embryonic stem cell (hESC)-derived EVs (hESC-EVs) as controls. Based on in-depth proteomic analysis, we revealed remarkable differences between hRPC-EVs and hESC-EVs. A comparison between EVs and their respective cells of origin demonstrated that the protein loading of hRPC-EVs was more selective than that of hESC-EVs. In particular, hESC-EVs were enriched with proteins related to angiogenesis and cell cycle, whereas hRPC-EVs were enriched with proteins associated with immune modulation and retinal development. More importantly, compared with that of hESC-EVs, hRPC-EVs exhibited a lower correlation with cell proliferation and a unique capacity to regulate lipid metabolism. It was further confirmed that hRPC-EVs potentially eliminated lipid deposits, inhibited lipotoxicity and oxidative stress, and enhanced phagocytosis and survival of oleic acid-treated ARPE-19 cells. Mechanistically, hRPC-EVs are integrated into the mitochondrial network of oleic acid-treated ARPE-19 cells, and increased the level of mitochondrial fatty acid ß-oxidation-related proteins. Thus, organoid-derived hRPC-EVs represent a promising source of cell-free therapy for RD, especially for blinding diseases related to abnormal lipid metabolism in RPE cells.