Akt inhibition-dependent downregulation of the Wnt/β-Catenin Signaling pathway contributes to antimony-induced neurotoxicity

A Prospective Cohort Study of Antimony Exposure and Cognitive Impairment in Older Adults - China, 2017-2021

What is already known about this topic?

Antimony (Sb) has been identified as a new neurotoxicant that impacts neurological functions in animal studies. However, its effects on the human population remain unknown.

What is added by this report?

The study reveals that there is an association between exposure to Sb and a higher incidence of cognitive impairment in older adults. The dose-response curve demonstrates that the risk of cognitive impairment consistently increased with higher levels of Sb exposure without a discernible threshold.

What are the implications for public health practice?

Reducing exposure to Sb may have a beneficial effect in delaying or preventing the onset of cognitive impairment. This intervention has the potential to significantly decrease the disease burden associated with cognitive impairment, ultimately contributing to social development.

Stem cell factor protects against chronic ischemic retinal injury by modulating on neurovascular unit

Retinal ischemia is a significant factor in various vision-threatening diseases, but effective treatments are currently lacking. This study explores the potential of stem cell factor (SCF) in regulating the neurovascular unit as a therapeutic intervention for retinal ischemic diseases. A chronic retinal ischemia model was established in Brown Norway rats using bilateral common carotid artery occlusion (BCCAO). Subsequent SCF treatment resulted in a remarkable recovery of retinal function, as indicated by electroretinogram, light/dark transition test, and optokinetic head tracking test results. Histological examination demonstrated a significant increase in the number of retinal neurons and an overall thickening of the retina. Immunofluorescence confirmed these findings and further demonstrated that SCF treatment regulated retinal remodeling. Notably, SCF treatment ameliorated the disrupted expression of synaptic markers in the control group's BCCAO rats and suppressed the activation of Müller cells and microglia. Retinal whole-mount analysis revealed a significant improvement in the abnormalities in retinal vasculature following SCF treatment. Transcriptome sequencing analysis revealed that SCF-induced transcriptome changes were closely linked to the Wnt7 pathway. Key members of the Wnt7 pathway, exhibited significant upregulation following SCF treatment. These results underscore the protective role of SCF in the neurovascular unit of retinal ischemia rats by modulating the Wnt7 pathway. SCF administration emerges as a promising therapeutic strategy for retinal ischemia-related diseases, offering potential avenues for future clinical interventions.

Isoliquiritigenin Inhibits Oral Squamous Cell Carcinoma and Overcomes Chemoresistance by Destruction of Survivin

The oncoprotein survivin plays a pivotal role in controlling cell division and preventing apoptosis by inhibiting caspase activation. Its significant contribution to tumorigenesis and therapeutic resistance has been well established. Isoliquiritigenin (ISL), a natural compound, has been recognized for its powerful inhibitory effects against various tumors. However, whether ISL exerts regulatory effects on survivin and its underlying mechanism in oral squamous cell carcinoma (OSCC) remains unclear. Here, we found that ISL inhibited the viability and colony formation of OSCC, and promoted their apoptosis. The immunoblotting data showed that ISL treatment significantly decreased survivin expression. Mechanistically, ISL suppressed survivin phosphorylation on Thr34 by deregulating Akt-Wee1-CDK1 signaling, which facilitated survivin for ubiquitination degradation. ISL inhibited CAL27 tumor growth and decreased p-Akt and survivin expression in vivo. Meanwhile, survivin overexpression caused cisplatin resistance of OSCC cells. ISL alone or combined with cisplatin overcame chemoresistance in OSCC cells. Overall, our results revealed that ISL exerted potent inhibitory effects via inducing Akt-dependent survivin ubiquitination in OSCC cells.

Associations between urinary heavy metals and anxiety among adults in the National Health and Nutrition Examination Survey (NHANES), 2007-2012

BACKGROUND

Few studies have investigated the associations between heavy metals and anxiety. The purpose of this study was to examine the associations between single and combined exposure to heavy metals and anxiety.

METHODS

This study employed data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2012. Anxiety was assessed by patients self-reporting the number of anxious days per month. First, we evaluated the associations between 10 heavy metals single exposure and anxiety by multivariable logistic regression. We then selected 5 heavy metals (cadmium, antimony, cobalt, tungsten, and uranium) for further analysis by elastic net regression. Subsequently, principal component analysis (PCA), weighted quantile regression (WQS), and Bayesian kernel machine regression (BKMR) were utilized to evaluate the associations between 5 heavy metals co-exposure and anxiety.

RESULTS

This study included 4512 participants, among whom 1206 participants were in an anxiety state. Urinary cadmium and antimony were separately related to an increased risk of anxiety (p for trend <0.01 and < 0.01, respectively). In PCA analysis, PC1 was associated with an increased risk of anxiety (p for trend <0.001). In WQS analysis, the positive WQS index was substantially linked with the risk of anxiety (OR (95%CI): 1.23 (1.04,1.39)). In BKMR analysis, the overall effects of co-exposure to heavy metals were positively connected with anxiety.

CONCLUSION

Our study identified a positive correlation between individual exposure to cadmium and antimony and the risk of anxiety. Additionally, the co-exposure to cadmium, antimony, cobalt, tungsten, and uranium was associated with an increased risk of anxiety.

Sex-specific associations between nine metal mixtures in urine and urine flow rate in US adults: NHANES 2009-2018

Background

The urinary system serves as a crucial pathway for eliminating metallic substances from the body, making it susceptible to the effects of metal exposure. However, limited research has explored the association between metal mixtures and bladder function. This study aims to investigate the relationship between urinary metal mixtures (specifically barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten) and urine flow rate (UFR) in the general population, utilizing multiple mixture analysis models.

Methods

This study utilizes data obtained from the National Health and Nutrition Examination Survey. After adjusting for relevant covariates, we assessed the correlations between metal mixtures and UFR using three distinct analysis models: weighted quantile sum (WQS), quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR). Additionally, a gender-stratified analysis was conducted. Finally, we also performed sensitivity analyses.

Results

A total of 7,733 subjects were included in this study, with 49% being male. The WQS regression model, when fitted in the positive direction, did not yield any significant correlations in the overall population or in the male and female subgroups. However, when analyzed in the negative direction, the WQS index exhibited a negative correlation with UFR in the overall group (β = -0.078; 95% CI: -0.111, -0.045). Additionally, a significant negative correlation between the WQS index and UFR was observed in the female group (β = -0.108; 95% CI: -0.158, -0.059), while no significant correlation was found in the male group. The results obtained from the qgcomp regression model were consistent with those of the WQS regression model. Similarly, the BKMR regression model revealed a significant negative correlation trend between metal mixtures and UFR, with cadmium and antimony potentially playing key roles.

Conclusion

Our study revealed a significant negative correlation between urinary metal mixture exposure and mean UFR in US adults, with notable gender differences. Specifically, higher urinary levels of cadmium and antimony were identified as potential key factors contributing to the decrease in mean UFR. These findings significantly contribute to the existing knowledge on the impact of metal mixtures on bladder function and provide valuable insights for safeguarding bladder health and preventing impaired bladder function.

Ponatinib Represses Latent HIV-1 by Inhibiting AKT-mTOR

Although antiretroviral therapy (ART) is effective in suppressing viral replication, it does not cure HIV-1 infection due to the presence of the viral latent reservoir. Rather than reactivating the latent viruses, the "block and lock" strategy aims to shift the viral reservoir to a deeper state of transcriptional silencing, thus preventing viral rebound after ART interruption. Although some latency-promoting agents (LPAs) have been reported, none of them have been approved for clinical application due to cytotoxicity and limited efficacy; therefore, it is important to search for novel and effective LPAs. Here, we report an FDA-approved drug, ponatinib, that can broadly repress latent HIV-1 reactivation in different cell models of HIV-1 latency and in primary CD4+ T cells from ART-suppressed individuals ex vivo. Ponatinib does not change the expression of activation or exhaustion markers on primary CD4+ T cells and does not induce severe cytotoxicity and cell dysfunction. Mechanistically, ponatinib suppresses proviral HIV-1 transcription by inhibiting the activation of the AKT-mTOR pathway, which subsequently blocks the interaction between key transcriptional factors and the HIV-1 long terminal repeat (LTR). In summary, we discovered a novel latency-promoting agent, ponatinib, which could have promising significance for future applications of HIV-1 functional cure.

Evaluation of transcriptomic molecular classification, biological behavior, and clinicopathological features in hepatocellular carcinoma

BACKGROUND

Studies in France, Korea, and Singapore found that G1-G6 transcriptomes are involved in hepatocellular carcinoma (HCC) carcinogenesis. However, the suitability of this method in Chinese HCC patients has remained unknown.

METHODS

The correlation between the G1-G6 molecular classification and clinicopathological features were analyzed in 107 Chinese HCC patients through the retrospective cohort study. RNA sequencing and bioinformatics analysis were performed to screen related targets and molecular signaling pathways.

RESULTS

We found that the G1-G3 subgroups were associated with high serum alpha-fetoprotein (AFP) level, high copy number of hepatitis B virus (HBV) DNA, complex histopathological structure, macrovascular invasion. The G1 subgroup was mainly related to liver cancer stemness, and G3 subgroup showed the worst prognosis. The G5 and G6 subgroups were associated with activation of the Wnt/β-catenin pathway. Compared with the G4-G6 group, the G1-G3 group showed significantly higher expression levels of regenerating family member 1 beta (REG1B), regenerating family member 3 gamma (REG3G), and inositol 1,4,5-trisphosphate receptor type 1 (ITPR1), and enriched calcium signaling pathway.

CONCLUSIONS

This study enhances our understanding of the heterogenicity of China HCC and indicates that the G1-G6 signatures can be used to identify predictive biomarkers against HCC patients in China.

Level-specific associations of urinary antimony with cognitive function in US older adults from the National Health and Nutrition Examination Survey 2011-2014

BACKGROUND

We have looked at antimony (Sb) as a new neurotoxin which causes neuronal apoptosis in animal studies. At the population level, however, there is no direct evidence for a relationship between Sb exposure and cognitive performance.

METHOD

The study comprehensively assessed the correlation between urinary antimony levels and cognitive test scores in 631 creatinine-corrected older persons using data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014.

RESULTS

Using logistic regression, the study looked at the prevalence of cognitive impairment at different levels of urine antimony concentrations and found that, after controlling for covariates, higher doses of urinary antimony were positively associated with cognitive function compared to controls, odds ratio (ORs) with 95% confidence interval (CI) were 0.409 (0.185-0.906) and 0.402 (0.186-0.871) respectively. Restricted cubic spline curves showed a non-linear and dose-specific correlation between urinary antimony and cognitive performance, with lower doses associated with better cognitive performance, while higher doses may be associated with cognitive impairment.

CONCLUSIONS

Our data provide evidence for a correlation between Sb and cognitive function at the population level, although the specific mechanisms need to be investigated further.

Novel GSK-3 kinase inhibitor Pym-5 induces GSK-3β rather than GSK-3α-dependent melanogenesis in murine melanoma cells

BACKGROUND

Glycogen synthase kinase-3 (GSK-3) inhibitors are considered to activate Wnt/β-Catenin, which remains a controversial topic in melanoma treatment.

OBJECTIVE

Here, we have developed Pym-5, an attractive GSK-3 inhibitor. Using Pym-5 as a chemical tool to probe the GSK-3 biology, we aimed to investigate the potential of GSK-3 inhibition as a strategy of melanoma treatment and underlying mechanisms.

METHODS

Using pigment B16 and B16BL6 murine melanoma model in vitro and a zebrafish pigmentation model in vivo, we investigated Pym-5-meditaed activation of Wnt/β-Catenin, melanogenesis and antitumor response in melanoma treatment.

RESULTS

We found that Pym-5 delayed the growth and promoted melanogenesis of melanoma cells. Pym-5 activated the transcription of β-Catenin and responsive targets genes (AXIN2 and MITF), melanin biosynthesis genes (TYR, TYRP1 and TYRP2) and eventually elevated the production of melanin. Interestingly, genetic inactivation of GSK-3β, but not its paralogue GSK-3α, compromised Pym-5-mediated melanogenesis in B16 and B16BL6 cells.

CONCLUSION

These data provide insight into the potential therapeutic benefits obtained from activation of Wnt/β-Catenin signaling pathway and how Pym-5 can regulate melanin production and the rationale for future clinical application of GSK-3 inhibitor in melanoma patients.

Disruption of mitochondrial redox homeostasis as a mechanism of antimony-induced reactive oxygen species and cytotoxicity

Occupational and environmental Sb exposure has been associated with increased risk of respiratory diseases and lung cancer, but the toxicities and molecular mechanisms of Sb have been less investigated. In the present study, we first analyzed the Sb toxicity profile of lung adenocarcinoma A549 cells, and found that Sb dose-dependently decreased the cell viability and arrested cell cycle at G2/M but did not induce apoptosis. We next investigated the role of reactive oxygen species (ROS) involved in Sb-induced cytotoxicity. The results showed that Sb did not significantly induce cytosolic ROS production by NADPH oxidase (NOX) and the NOX inhibitors did not ameliorate the Sb-induced cell viability loss in A549 cells. However, the level of mitochondrial ROS (mtROS) was significantly increased in Sb-exposed cells and the mitochondria-targeted antioxidant significantly improved cell viability. These results suggested that mitochondria but not NOX is the major source of ROS production and mtROS plays a critical role in Sb-induced cytotoxicity. Furthermore, we found that Sb induced mitochondria dysfunction including the significant decrease of ATP level and mitochondrial membrane potential. Finally, Sb exposure decreased the activity of complex I and complex III, the level of -SH and GSH in mitochondria, and the activity of mitochondrial GR, GPx and TrxR, but increased the mitochondrial SOD activity, suggesting the disruption of mitochondrial redox homeostasis. Taken together, these findings suggested that Sb impaired mitochondrial redox homeostasis, resulting in formation of mtROS, thereby inhibited mitochondrial function and led to cytotoxicity.

GPX4 degradation via chaperone-mediated autophagy contributes to antimony-triggered neuronal ferroptosis

Exposure to antimony (Sb), recently identified as a nerve pollutant, can result in neuron damage; but, associated-neurotoxicological mechanisms were still not clear. Herein, we assessed the role of ferroptosis in Sb-mediated neurotoxicity and clarified the underlying mechanism. Following Sb exposure, ferroptosis was significantly promoted in vivo and in vitro. Moreover, following use of ferrostatin-1 (fer-1) to inhibit ferroptosis, Sb-induced ferroptosis in PC12 cells was effectively attenuated. Sb accelerated lysosomal transport and subsequent degradation of glutathione peroxidase 4 (GPX4), resulting in ferroptosis. Furthermore, chaperone-mediated autophagy (CMA) was activated following treatment with Sb, while inhibition of CMA by lysosomal associated protein 2 A (LAMP2A) knockdown attenuated Sb-induced GPX4 degradation. Sb treatment also increased expression of the chaperones heat shock cognate protein 70 (HSC70) and heat shock protein 90 (HSP90) and the lysosome receptor LAMP2A, and increased binding of HSP90, HSC70, and LAMP2A with GPX4 was observed, indicating increased formation of the chaperone-GPX4 complex. Finally, GPX4 overexpression significantly protected PC12 cells from activation of Sb-stimulated ferroptosis and subsequent cytotoxicity. Collectively, our results provide a original mechanism by which Sb triggers neurotoxicity, to concluded that Sb stimulates neuronal ferroptosis through CMA-mediated GPX4 degradation.

Stimulation of C-Kit+ Retinal Progenitor Cells by Stem Cell Factor Confers Protection Against Retinal Degeneration

C-kit/CD117, expressed in a series of tissue-specific progenitor cells, plays an important role in tissue regeneration and tissue homeostasis. We previously demonstrated that organoid-derived c-kit⁺ retinal progenitor cells can facilitate the restoration of degenerated retina. Meanwhile, we have identified a population of endogenous c-kit⁺ cells in retinas of adult mouse. However, the exact role of these cells in retinal degeneration remains unclear. Here, we demonstrated that stimulation of endogenous c-kit⁺ cells by stem cell factor (SCF) conferred protection against retinal degeneration. Retinal degeneration was induced by intravitreal injection of N-methyl-D-aspartate (NMDA). NMDA challenge increased the total number of c-kit⁺ cells in the retinal ganglion cell layer (GCL), while deregulated the protein level of SCF, which was mainly expressed in Müller cells. Both flash electroretinogram (fERG) and light/dark transition tests showed that intravitreal injection of SCF effectively improved the visual function of NMDA-treated mice. Mechanistically, SCF administration not only prevented the loss of retinal ganglion cells (RGCs), but also maintained the function of RGCs as quantified by fERG. Further, we performed transcriptome sequencing analysis of the retinal cells isolated from SCF-treated mice and the parallel control. Gene Ontology analysis showed that SCF-induced transcriptome changes were closely correlated with eye development-related pathways. Crystallins and several protective factors such as Pitx3 were significantly upregulated by SCF treatment. Our results revealed the role of SCF stimulated c-kit⁺ cells in the protection of RGCs in NMDA-treated mice, via inhibiting the loss of RGCs. Administration of SCF can act as a potent strategy for treating retinal degeneration-related diseases.

Propofol suppresses adipose-derived stem cell progression via PI3K/AKT-Wnt signaling pathway

Adipose-derived stem cell (ADSC) transplantation has become a prospective way to treat cardiovascular diseases and skin traumas. Propofol, a short-acting intravenous anesthetic agent, plays an important role in the induction and maintenance of general anesthesia. In this study, we investigated the effects of propofol on ADSCs. The flow cytometry results showed that ADSCs were positive for CD29, CD44, and CD90 and negative for CD31, CD34, and CD45. The results of MTT and BrdU assays demonstrated that propofol impeded the proliferation of ADSCs. The cell scratch test showed that propofol had an inhibitory effect on the migration of ADSCs. Transwell assay showed that invasive ASDC counts decreased significantly after propofol treatment. Propofol also promoted ADSC apoptosis and arrested ADSCs in the G0/G1 phase. All these effects showed in a dose-dependent manner that the higher the concentration, the stronger the effect. Western blot analysis revealed decreased levels of FAK, PI3K, AKT, and GSK3β phosphorylation, while the phosphorylation of β-catenin increased after 48 h of treatment with propofol. The findings above indicated that the PI3K/AKT-Wnt pathways mediated propofol-inhibited ADSC proliferation, providing new insights into the propofol application in ADSCs.

Role of neurotoxicants in the pathogenesis of Alzheimer's disease: a mechanistic insight

Alzheimer's disease (AD) is the most conspicuous chronic neurodegenerative syndrome, which has become a significant challenge for the global healthcare system. Multiple studies have corroborated a clear association of neurotoxicants with AD pathogenicity, such as Amyloid beta (Aβ) proteins and neurofibrillary tangles (NFTs), signalling pathway modifications, cellular stress, cognitive dysfunctions, neuronal apoptosis, neuroinflammation, epigenetic modification, and so on. This review, therefore, aimed to address several essential mechanisms and signalling cascades, including Wnt (wingless and int.) signalling pathway, autophagy, mammalian target of rapamycin (mTOR), protein kinase C (PKC) signalling cascades, cellular redox status, energy metabolism, glutamatergic neurotransmissions, immune cell stimulations (e.g. microglia, astrocytes) as well as an amyloid precursor protein (APP), presenilin-1 (PSEN1), presenilin-2 (PSEN2) and other AD-related gene expressions that have been pretentious and modulated by the various neurotoxicants. This review concluded that neurotoxicants play a momentous role in developing AD through modulating various signalling cascades. Nevertheless, comprehension of this risk agent-induced neurotoxicity is far too little. More in-depth epidemiological and systematic investigations are needed to understand the potential mechanisms better to address these neurotoxicants and improve approaches to their risk exposure that aid in AD pathogenesis.Key messagesInevitable cascade mechanisms of how Alzheimer's Disease-related (AD-related) gene expressions are modulated by neurotoxicants have been discussed.Involvement of the neurotoxicants-induced pathways caused an extended risk of AD is explicited.Integration of cell culture, animals and population-based analysis on the clinical severity of AD is addressed.

Antimony-induced astrocyte activation via mitogen-activated protein kinase activation-dependent CREB phosphorylation

Recent studies suggest that the chemical element antimony (Sb) is neurotoxic; however, the molecular mechanisms behind Sb-related neuronal damage are currently unknown. In this study, we found that Sb exposure promoted astrocyte proliferation and increased the expression of inducible nitric oxide synthase (iNOS) and glial fibrillary acidic protein (GFAP), two key protein markers of reactive astrogliosis, at both the gene and protein level, suggesting that Sb induced astrocyte activation. Moreover, the p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-related kinase (ERK) pathways were activated following Sb exposure. Inhibition of p38 MAPK reduced Sb-induced iNOS and GFAP upregulation, while inhibiting ERK reduced GFAP expression only, in Sb-exposed C6 cells. Sb treatment also induced the phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), and the inhibition of CREB caused a reduction in Sb-induced GFAP and iNOS expression. Furthermore, inhibiting both p38 MAPK and ERK effectively alleviated CREB phosphorylation in Sb-exposed C6 cells. Taken together, our results suggest that p38 MAPK and ERK activation mediate Sb-induced astrocyte activation through CREB phosphorylation. These results help to clarify the molecular mechanisms underlying Sb-associated neurotoxicity.

Artemisia annua L. Polyphenol-Induced Cell Death Is ROS-Independently Enhanced by Inhibition of JNK in HCT116 Colorectal Cancer Cells

c-Jun N-terminal kinase (JNK) is activated by chemotherapeutic reagents including natural plant polyphenols, and cell fate is determined by activated phospho-JNK as survival or death depending on stimuli and cell types. The purpose of this study was to elucidate the role of JNK on the anticancer effects of the Korean plant Artemisia annua L. (pKAL) polyphenols in p53 wild-type HCT116 human colorectal cancer cells. Cell morphology, protein expression levels, apoptosis/necrosis, reactive oxygen species (ROS), acidic vesicles, and granularity/DNA content were analyzed by phase-contrast microscopy; Western blot; and flow cytometry of annexin V/propidium iodide (PI)-, dichlorofluorescein (DCF)-, acridine orange (AO)-, and side scatter pulse height (SSC-H)/DNA content (PI)-stained cells. The results showed that pKAL induced morphological changes and necrosis or late apoptosis, which were associated with loss of plasma membrane/Golgi integrity, increased acidic vesicles and intracellular granularity, and decreased DNA content through downregulation of protein kinase B (Akt)/β-catenin/cyclophilin A/Golgi matrix protein 130 (GM130) and upregulation of phosphorylation of H2AX at Ser-139 (γ-H2AX)/p53/p21/Bak cleavage/phospho-JNK/p62/microtubule-associated protein 1 light chain 3B (LC3B)-I. Moreover, JNK inhibition by SP600125 enhanced ROS-independently pKAL-induced cell death through downregulation of p62 and upregulation of p53/p21/Bak cleavage despite a reduced state of DNA damage marker γ-H2AX. These findings indicate that phospho-JNK activated by pKAL inhibits p53-dependent cell death signaling and enhances DNA damage signaling, but cell fate is determined by phospho-JNK as survival rather than death in p53 wild-type HCT116 cells.

Positive regulation of the CREB phosphorylation via JNK-dependent pathway prevents antimony-induced neuronal apoptosis in PC12 cell and mice brain

Antimony (Sb) is a potentially toxic chemical element abundantly found in the environment. We previously reported that Sb promoted neuronal deathvia reactive oxygen species-dependent autophagy. Here, we assessed the role of cyclic adenosine monophosphate response element-binding protein (CREB) in Sb-induced neuronal damage. We found that Sb treatment induced CREB phosphorylation and neuronal apoptosis both in vitro and in vivo. Interestingly, inhibition of CREB's transcriptional activity with 666-15 dramatically enhanced apoptosis in PC12 cells by downregulating B-cell lymphoma 2 (Bcl-2). Additionally, Sb activated ERK, JNK, and p38 signaling ; however, only JNK promoted CREB phosphorylation. In conclusion, our findings suggest that CREB phosphorylation by JNK attenuates Sb-induced neuronal apoptosis via Bcl-2 upregulation. These data suggest that JNK-dependent CREB activation prevents neurons from Sb-induced apoptosis and guides the development of novel strategies to prevent Sb-induced neurotoxicity.

Initiation of PI3K/AKT pathway by IGF-1 decreases spinal cord injury-induced endothelial apoptosis and microvascular damage

AIM

Apoptosis of endothelial cells (ECs) is a crucial factor in blood-spinal cord barrier (BSCB) disruption post spinal cord injury (SCI). Insulin-like growth factor-1 (IGF-1) is a protective cytokine that plays an important role in multiple diseases, whereas the distinct role in SCI-induced remains critical questions to address. Here we designed to explore the role and underlying mechanism of IGF-1 in endothelial damage after SCI.

MAIN METHODS

In the current study, we established mouse microvascular endothelial cells (MVECs) injury model via LPS and cDNA of IGF-1 was transfected into MVECs. In vivo SCI mice, overexpression of IGF-1 (SCI-IGF-1) and its corresponding empty vehicle (SCI-NC) were conducted using lentivirus, then apoptosis degree, component of tight junction, and inflammatory damage were evaluated.

KEY FINDINGS

IGF-1 treatment in MVECs displayed a milder apoptosis and cell damage under LPS insult. IGF-1 increased the level of PI3K/AKT pathway, which impeded the procedure of apoptosis. Blocking of PI3K/AKT pathway markedly neutralized the effect of IGF-1 treatment. Transfection of excess IGF-1 into SCI mice significantly corrected microenvironment of neural tissue repair, reduced area of injured core and improved functional recovery with greater activation of PI3K/AKT pathway.

SIGNIFICANCE

The results above argue that the promising roles played by IGF-1 is potentially vital for developing effective future therapies in SCI.