Orbital and eyelid diseases: The next breakthrough in artificial intelligence?

Orbital and eyelid disorders affect normal visual functions and facial appearance, and precise oculoplastic and reconstructive surgeries are crucial. Artificial intelligence (AI) network models exhibit a remarkable ability to analyze large sets of medical images to locate lesions. Currently, AI-based technology can automatically diagnose and grade orbital and eyelid diseases, such as thyroid-associated ophthalmopathy (TAO), as well as measure eyelid morphological parameters based on external ocular photographs to assist surgical strategies. The various types of imaging data for orbital and eyelid diseases provide a large amount of training data for network models, which might be the next breakthrough in AI-related research. This paper retrospectively summarizes different imaging data aspects addressed in AI-related research on orbital and eyelid diseases, and discusses the advantages and limitations of this research field.

Ivermectin inhibits tumor metastasis by regulating the Wnt/ß-catenin/integrin ß1/FAK signaling pathway.

Tumor metastasis is the major cause of cancer mortality; therefore, it is imperative to discover effective therapeutic drugs for anti-metastasis therapy. In the current study, we investigated whether ivermectin (IVM), an FDA-approved antiparasitic drug, could prevent cancer metastasis. Colorectal and breast cancer cell lines and a cancer cell-derived xenograft tumor metastasis model were used to investigate the anti-metastasis effect of IVM. Our results showed that IVM significantly inhibited the motility of cancer cells in vitro and tumor metastasis in vivo. Mechanistically, IVM suppressed the expressions of the migration-related proteins via inhibiting the activation of Wnt/ß-catenin/integrin ß1/FAK and the downstream signaling cascades. Our findings indicated that IVM was capable of suppressing tumor metastasis, which provided the rationale on exploring the potential clinical application of IVM in the prevention and treatment of cancer metastasis.

Body fluids from the rat exposed to chlorpyrifos induce cytotoxicity against the corresponding tissue-derived cells in vitro.

BACKGROUND: This study aims to establish an in vitro monitoring approach to evaluate the pesticide exposures. We studied the in vitro cytotoxicity of three different body fluids of rats to the respective corresponding tissue-derived cells. METHODS: Wistar rats were orally administrated daily with three different doses of chlorpyrifos (1.30, 3.26, and 8.15 mg/kg body weight/day, which is equal to the doses of 1/125, 1/50, and 1/20 LD50, respectively) for consecutive 90 days. Blood samples as well as 24-hour urine and fecal samples were collected and processed. Then, urine, serum, and feces samples were used to treat the correspondent cell lines, i.e., T24 bladder cancer cells, Jurkat lymphocytes, and HT-29 colon cancer cells respectively, which derived from the correspondent tissues that could interact with the respective corresponding body fluids in organism. Cell viability was determined by using MTT or trypan blue staining. RESULTS: The results showed that urine, serum, and feces extract of the rats exposed to chlorpyrifos displayed concentration- and time-dependent cytotoxicity to the cell lines. Furthermore, we found that the cytotoxicity of body fluids from the exposed animals was mainly due to the presence of 3, 4, 5-trichloropyrindinol, the major toxic metabolite of chlorpyrifos. CONCLUSIONS: These findings indicated that urine, serum, and feces extraction, especially urine, combining with the corresponding tissue-derived cell lines as the in vitro cell models could be used to evaluate the animal exposure to pesticides even at the low dose with no apparent toxicological signs in the animals. Thus, this in vitro approach could be served as complementary methodology to the existing toolbox of biological monitoring of long-term and low-dose exposure to environmental pesticide residues in practice.

Individual and combined hepatocytotoxicity of DDT and cadmium in vitro.

The organochlorine insecticide dichlorodiphenyltrichloroethane (DDT) and heavy metal cadmium (Cd) are widespread environmental pollutants. They are persistent in the environment and can accumulate in organisms. Although the individual toxicity of DDT and Cd has been well documented, their combined toxicity is still not clear. Since liver is their common target, in this study, the individual and combined toxicity of DDT and Cd in human liver carcinoma HepG2 and human normal liver THLE-3 cell lines were investigated. The results showed that DDT and Cd inhibited the viability of HepG2 and THLE-3 cells dose-dependently and altered lysosomal morphology and function. Intracellular reactive oxygen species and lipid peroxidation levels were induced by DDT and Cd treatment. The combined cytotoxicity of DDT and Cd was greater than their individual cytotoxicity, and the interaction between Cd and DDT was additive on the inhibition of cell viability and lysosomal function of HepG2 cells. The interaction was antagonistic on the inhibition of cell viability of THLE-3 cells. These results may facilitate the evaluation of the cumulative risk of pesticides and heavy metal residues in the environment.

Lapatinib alleviates TOCP-induced axonal damage in the spinal cord of mouse.

Neuregulin-1 (NRG1), a family of EGF-like factors that activates ErbB receptors, can regulate the proliferation, migration, and myelinating of Schwann cells. We previously reported that NRG1/ErbB signal is responsible for organophosphate (OP)-induced delayed neuropathy (OPIDN) in hens, a susceptive animal model to neuropathic organophosphorous compounds. Our previous study discovered that a neuropathic OP, tri-o-cresyl phosphate (TOCP) activated NRG1/ErbB signaling pathway in both spinal cord and sciatic nerves of hens during the formation of OPIDN and lapatinib, a non-selective antagonist of ErbB1 and ErbB2 receptors, alleviated the toxicity. In this study, we intended to further look into the potential role of NRG1 in the pathogenesis of TOCP-induced axon damage in spinal cord and sciatic nerves and whether lapatinib could also rescue this damage in mice, an OPIDN-resistant animal model. The results revealed that no obvious toxic signs were observed after single TOCP exposure. However, slight histopathological wreck in lumbar spinal cord and sciatic nerves was found following TOCP intoxication, and the damage in sciatic nerves was characterized by axon degeneration of myelin sheath but not the loss of neural skeleton. Only histopathological damage induced by TOCP in spinal cord could be prevented by lapatinib. The translational expression of NRG1/ErbB signaling molecules was analyzed by both in vivo and in vitro studies. In general, NRG1/ErbB pathway was activated by TOCP while combined treatment with lapatinib attenuated TOCP-induced NRG1/ErbB signaling cascade. The results implied that NRG1/ErbB system may predominately play functional role in spinal cord (central nervous system) but not in sciatic nerves (peripheral nervous system) of mouse subjected to neurotoxic OP, which was confirmed by the study in vitro that lapatinib was not able to attenuate TOCP-induced neurotoxicity in rodent Schwann cell line RSC 96 cells.

5­Nitro­2­(3­phenylpropylamino) benzoic acid induces apoptosis of human lens epithelial cells via reactive oxygen species and endoplasmic reticulum stress through the mitochondrial apoptosis pathway.

Cataracts have a high incidence and prevalence rate worldwide, and they are the leading cause of blindness. Lens epithelial cell (LEC) apoptosis is often analysed in cataract research since it is the pathological basis of cataracts, except for congenital cataract. Chloride channels are present in ocular tissues, such as in trabecular cells, LECs and other cells. They serve an important role in apoptosis and participate in endoplasmic reticulum (ER) stress and oxidative stress. However, their role in the apoptosis of LECs has not been discussed. The present study examined the effects of the chloride channel blocker 5­nitro­2­(3­phenylpropylamino) benzoic acid (NPPB) in human LECs (HLECs) to elucidate the role of NPPB in HLECs and investigate the role and mechanism of chloride channels in cataract formation. HLECs were exposed to NPPB. Cell survival rate was evaluated using Cell Counting Kit­8 assays. Oxidative stress was detected as reactive oxygen species (ROS) in cells by using a ROS assay kit. Apoptosis was examined by assessing mitochondrial membrane potential and using a JC­1 assay kit, and western blot analysis was performed to measure the expression levels of mitochondrial­dependent apoptosis pathway­associated proteins. ER stress was evaluated by determining the intracellular calcium ion fluorescence intensity, and western blot analysis was performed to measure ER stress­associated protein expression. The results revealed that NPPB treatment decreased the viability of HLECs and increased apoptosis. Additionally, NPPB increased intracellular ROS levels, as well as the number of JC­1 monomers and the protein expression levels of B­cell lymphoma­2 (Bcl­2)­associated X and cleaved caspase­3, and decreased Bcl­2 protein expression. NPPB increased intracellular calcium ions, the protein expression levels of activating transcription factor 6, JNK, C/EBP homologous protein and caspase­12, and the phosphorylation of protein kinase R­like endoplasmic reticulum kinase. N­acetylcysteine and 4­phenylbutyric acid inhibited NPPB­induced oxidative stress, ER stress and apoptosis. Therefore, NPPB treatment decreased cell viability and promoted apoptosis of HLECs via the promotion of oxidative and ER stress.

Grub polypeptide extracts protect against oxidative stress through the NRF2-ARE signaling pathway.

Grub polypeptide extracts (GPEs) have antioxidant effects; however, their underlying molecular mechanisms are unknown. This study explored the antioxidant molecular mechanism of GPE via the nuclear factor-erythroid 2-related factor 2 (NRF2)-antioxidant response element (ARE) signaling pathway in C2C12 muscle satellite cells exposed to oxidative stress. The effects of GPE/or H2O2 on C2C12 were investigated by the MTT (3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) viability assay and immunofluorescence and small interfering RNA (siRNA) analyses. The cell viability, cell damage, intracellular reactive oxygen species (ROS) levels, and NRF2 signaling pathways related to proteins were measured. GPE significantly increased the antioxidant capacity of cells, evident by increased cell viability and decreased lactate dehydrogenase leakage, DNA damage, malondialdehyde content, and ROS level. GPE also markedly increased mRNA expression levels and activities of antioxidant enzymes including superoxidase 1 and 2, catalase, and glutathione peroxidase. In addition, GPE increased the gene and protein expression of NRF2 and heme oxygenase 1 by promoting NRF2 translocation from the cytoplasm to the nucleus and activating NRF2-ARE signaling pathways. The antioxidant effects of GPE through these signaling pathways were further confirmed by NRF2-specific siRNA silencing. Thus, GPE enhances antioxidant capacity and alleviates oxidative damage of C2C12 cells via the NRF2-ARE signaling pathway.

Metabolomic biomarkers in urine of rats following long-term low-dose exposure of cadmium and/or chlorpyrifos.

Heavy metals and pesticides can be easily enriched in food chains and accumulated in organisms, thus pose significant threat to human health. However, their combined effects for long-term exposure at low dose has not been thoroughly investigated; especially there was no biofluid biomarker available to noninvasively diagnose the toxicosis of the combined exposure of the two chemicals at their low levels. In this study, we investigated the change of urine metabolites of rats with 90-day exposure to heavy metal cadmium (Cd) and/or organophosphorus pesticide chlorpyrifos (CPF) using gas chromatography-mass spectrometry (GC-MS)-based metabolomics approach. Our results showed that the interaction of Cd and CPF mainly displayed an antagonistic effect. We identified the panels of metabolite biomarkers in urine: benzoic acid and mannose were unique biomarkers for Cd exposure; creatinine and N-phenylacetyl glycine were unique biomarkers for CPF exposure; anthranilic acid, ribitol, and glucose were unique biomarkers for Cd plus CPF exposure. Our results suggest that 90-day exposure to Cd and/or CPF could cause a disturbance in energy and amino acid metabolism. And urine metabolomics analysis can help understand the toxicity of low dose exposure to mixed environmental chemicals.

Identification of metabolite biomarkers in serum of rats exposed to chlorpyrifos and cadmium.

Chlorpyrifos (CPF) and cadmium (Cd) are widespread environmental pollutants, which are often present in drinking water and foods. However, the combined effects of CPF and Cd were not entirely clear at present. There was also no biomarker available to diagnose the poisoning of the two chemicals at low dose for long-term exposures. In this study, we investigated the change of serum metabolites of rats with subchronic exposure to CPF, Cd, and CPF plus Cd using gas chromatography-mass spectrometer-based metabolomics approach. We performed a stepwise optimization algorithm based on receiver operating characteristic to identify serum metabolite biomarkers for toxic diagnosis of the chemicals at different doses after 90-day exposure. We found that aminomalonic acid was the biomarker for the toxicity of Cd alone administration, and serine and propanoic acid were unique biomarkers for the toxicities of CPF plus Cd administrations. Our results suggest that subchronic exposure to CPF and Cd alone, or in combination at their low doses, could cause disturbance of energy and amino acid metabolism. Overall, we have shown that analysis of serum metabolomics can make exceptional contributions to the understanding of the toxic effects following long-term low-dose exposure of the organophosphorus pesticide and heavy metal.

Ivermectin reverses the drug resistance in cancer cells through EGFR/ERK/Akt/NF-κB pathway.

BACKGROUND: Discovery and development of novel drugs that are capable of overcoming drug resistance in tumor cells are urgently needed clinically. In this study, we sought to explore whether ivermectin (IVM), a macrolide antiparasitic agent, could overcome the resistance of cancer cells to the therapeutic drugs. METHODS: We used two solid tumor cell lines (HCT-8 colorectal cancer cells and MCF-7 breast cancer cells) and one hematologic tumor cell line (K562 chronic myeloid leukemia cells), which are resistant to the chemotherapeutic drugs vincristine and adriamycin respectively, and two xenograft mice models, including the solid tumor model in nude mice with the resistant HCT-8 cells and the leukemia model in NOD/SCID mice with the resistant K562 cells to investigate the reversal effect of IVM on the resistance in vitro and in vivo. MTT assay was used to investigate the effect of IVM on cancer cells growth in vitro. Flow cytometry, immunohistochemistry, and immunofluorescence were performed to investigate the reversal effect of IVM in vivo. Western blotting, qPCR, luciferase reporter assay and ChIP assay were used to detect the molecular mechanism of the reversal effect. Octet RED96 system and Co-IP were used to determine the interactions between IVM and EGFR. RESULTS: Our results indicated that ivermectin at its very low dose, which did not induce obvious cytotoxicity, drastically reversed the resistance of the tumor cells to the chemotherapeutic drugs both in vitro and in vivo. Mechanistically, ivermectin reversed the resistance mainly by reducing the expression of P-glycoprotein (P-gp) via inhibiting the epidermal growth factor receptor (EGFR), not by directly inhibiting P-gp activity. Ivermectin bound with the extracellular domain of EGFR, which inhibited the activation of EGFR and its downstream signaling cascade ERK/Akt/NF-κB. The inhibition of the transcriptional factor NF-κB led to the reduced P-gp transcription. CONCLUSIONS: These findings demonstrated that ivermectin significantly enhanced the anti-cancer efficacy of chemotherapeutic drugs to tumor cells, especially in the drug-resistant cells. Thus, ivermectin, a FDA-approved antiparasitic drug, could potentially be used in combination with chemotherapeutic agents to treat cancers and in particular, the drug-resistant cancers.

Therapeutic hypothermia protects photoreceptors through activating Cirbp pathway.

Therapeutic hypothermia as a physical method to lower the brain temperature of patients has been widely used in clinics as an effective and necessary step during the treatment of acute brain injury or edema. However, due to limitations of the ocular structure, the application of hypothermia in retinal neuroprotection still has an obvious barrier. Here, the neuroprotective mechanism produced by hypothermia in the retina was investigated, with the hopes of deciphering the key molecular targets of the signaling pathway to finally realize the ocular neuroprotection by regulating specific molecular targets. In present study, it was first demonstrated that hypothermia produced significant neuroprotection on photoreceptors (661 W cell) against glucose deprivation (GD)-induced injury in vitro and visible light-induced retinal damage in vivo. The results disclosed that hypothermia (32 °C) was able to attenuate the upregulation of heme oxygenase-1, cleaved Caspase-3, cleaved Caspase-9, and B-cell lymphoma-2-associated X caused by GD, and restored the decline of protective factor B-cell lymphoma-2 as well. Moreover, hypothermia suppressed the excessive generation of intracellular reactive oxygen species and depolarization of mitochondrial membrane potential, and showed marked neuroprotection against GD-induced damage in photoreceptors, which significantly reduced cell death percentage in vitro. In in vivo experiments, it was found that hypothermia was able to protect retinal function against light injury, restoring the decline of a-waves and b-waves in electroretinograms and maintaining the thickness of the retinal outer nuclear layer. Furthermore, hypothermia blocked the visible light-induced cell death pathway in the retina, suppressing poly(ADP-ribose) polymerase-1 activation. More importantly, it was demonstrated that cold-inducible RNA-binding protein (Cirbp) as a key molecular target played an important role in hypothermia-induced neuroprotection, which is the first proof of its function in ophthalmology. In in vitro experiments, hypothermia caused marked expression of Cirbp in photoreceptors. And reducing the expression of Cirbp with specific small interfering RNA was able to block the hypothermia-induced neuroprotection. Consistently, overexpressed Cirbp with Cirbp-gene-modified lentivirus mimicked the neuroprotection against GD-induced injury even under normal temperature (37 °C) conditions. Additionally, the overexpression of Cirbp was detected in hypothermia-treated retinas. These results indicate that hypothermia promotes neuroprotection in photoreceptors via activation of the Cirbp pathway. The study presented here suggests that therapeutic hypothermia may promote neuroprotection in the retina by activating Cirbp, and regulating Cirbp may mimic similar protection even under normal temperature conditions, which might be a specific molecular target in retinal neuroprotection.

Disruption of Kidney Metabolism in Rats after Subchronic Combined Exposure to Low-Dose Cadmium and Chlorpyrifos.

Cadmium (Cd) and chlorpyrifos (CPF) often coexist in the environment and induce combined toxicity to organisms. Here we studied the combined nephrotoxicity of environmentally relevant low doses of Cd and CPF. We treated the mice for 90 days with different doses of Cd and CPF and their mixtures via oral gavage. Then histopathological evaluation and biochemical analysis for kidney tissues were carried out. The change of metabolites in kidney was detected by using a metabolomics approach using GC-MS. We found that Cd, CPF, and their mixtures caused oxidative damage as well as disturbance of renal amino acid metabolism. We identified potential metabolite biomarkers in kidney, which included acetic acid for CPF treatment, glycerol and carboxylic acid for Cd treatment, and l-ornithine for the mixture of CPF and Cd treatment, respectively. In addition, we found that Cd promoted the metabolism of CPF in kidney. This may contribute to the result that the toxicity of the mixtures was lower than the sum of the toxicities of Cd and CPF alone. In conclusion, our results indicated that CPF and Cd could disrupt the kidney metabolism in rats even when they were exposed to a very low dose of CPF and Cd.

Effects of human bone morphogenetic protein 2 (hBMP2) on tertiary dentin formation.

Formation of tertiary dentin to maintain pulp vitality is a major odontoblastic response to dental pulp injury. Human bone morphogenetic protein 2 (hBMP2) can promote proliferation and differentiation of odontoblasts. Current study is interested in evaluating if the hBMP2 can promote the regeneration of tertiary dentin and cure dental pulp injury using the adenoviral vector to deliver hBMP2 cDNA into the pulp. Primary culture of dental pulp cells of exfoliated deciduous teeth (hDPCs) was established. Human serotype 5 adenoviral vector, AdCMV-hBMP2, was created. AdCMV-hBMP2 was used to transduce hDPCs in vitro and dental pulp cells in animal model in vivo. Data clearly demonstrated that hBMP2 increased ALP and mineralization. Reverse transcription-real time quantitative PCR (RT-QPCR) data showed that hBMP2 dramatically increased gene expressions of Runx2 (Runt-related transcription factor 2), ALP, Col Iα (Collagen 1a1), SP7 (Osterix), DMP1 (dentin matrix acidic phosphoprotein 1), DSPP (dentin sialophosphoprotein), and BSP (bonesialoprotein), which are normally involved in osteogenesis/odontogenesis. Data from in vivo assays demonstrated that hBMP2 promoted pulp cell proliferation and increased formation of tertiary dentin in dental pulp. Our in vitro and in vivo data suggest that hBMP2 gene can efficiently be delivered into the dental pulp cells by adenovirus, and show potential clinical application for the treatment of dental pulp damage.

Resveratrol protects photoreceptors by blocking caspase- and PARP-dependent cell death pathways.

Retinal degeneration is a major cause of severe vision loss and irreversible blindness and is characterized by progressive damage to retinal photoreceptor cells. Resveratrol (RSV) serves as an activator of the histone deacetylase, Sirt1, and has been shown to exert anti-oxidative properties. In this study, we mimicked retinal degeneration by subjecting photoreceptors (661 W cells) to glucose deprivation (GD) or light exposure. Under these conditions, we investigated the mechanisms underlying GD- or light exposure-induced cell death and the protective effect of RSV. We found that GD and light exposure resulted in mitochondrial dysfunction, oxidative stress, and cell death. Treatment of injured cells with RSV decreased the production of reactive oxygen species (ROS), improved the ratio of reduced/oxidized glutathione (GSH/GSSG), mitochondrial membrane potential and morphology, and reduced apoptosis. We used the caspase inhibitor, z-VAD-fmk, and a lentiviral-mediated shRNA knockdown of PARP-1 to reveal that GD and light exposure-induced cell death have different underlying mechanisms; GD triggered a caspase-dependent cell death pathway, whereas light exposure triggered a PARP-dependent cell death pathway. The level of caspase-9 and caspase-3, upregulated following GD, were reduced by treatment with RSV. Similarly, the level of PARP-1 and AIF, upregulated following light exposure, were decreased by treatment with RSV. Additionally, treatment with RSV elevated the protein expression and enzymatic activity of Sirt1 and a Sirt1 inhibitor reduced the protective effect of RSV against insult-induced cellular injuries, indicating that RSV's protective effect may involve Sirt1 activation. Finally, we investigated the neuroprotection of RSV in vivo. Administration of RSV to mice under extreme light exposure led to a suppression of the light-induced thinning of the outer nuclear layer (ONL) detected by hematoxylin and eosin (H&E) staining and restored retinal function evaluated by electroretinography (ERG). Taken together, our findings provide evidence that treatment with RSV has neuroprotective effects on both GD and light exposure-induced cell death pathways in photoreceptor cells.

Potential Role of Induced Pluripotent Stem Cells as Regenerative Medicine in Retinal Cell Damage.

Induced pluripotent stem cells (also called iPSCs) are somatic cells reprogrammed by overexpressing four nuclear transcriptional factors containing Sox2, Klf4, c-myc and Oct4 is the one of research hotspots. Its pluripotency, self-renewal capacity and wide accessibility to donor tissues have made possible the means for modified regenerative medicine. They are considered a possible basis of healthy tissue to cure diseases, like ophthalmic diseases, degenerative diseases, age-related macular degeneration (AMD), are primarily because of the weakening capability of photoreceptor cells, retinal ganglion cells (RGCs), retinal pigmented epithelium (RPE) or other retinal cells. And these retinal cells are unable to regenerate and currently there are no effective treatments to restore sight. iPSCs allow for the in vitro development of numerous varieties of retinal cells, and may treat these diseases by retinal transplantation. Although other stem cells could differentiate into retinal cells, iPSCs derived retinal cells might have numerous benefits as compared to other stem cell sources including embryonic stem (ES) cells. Mainly they would be directly obtained from the patient, therefore eradicating every probable chance of adverse immune responses. Second, making iPSCs just needs somatic cells, thus circumventing the valid ethical issues which limited the clinic use of ES cells derived from human. Third, iPSCs are parallel to ES cells in differentiation ability, they can be expanded in vitro and induced to differentiate into retinal cells, providing a renewable source for therapeutic applications and scientific researches. In this current review, we have concise latest progresses.

Clinical effects of 3-D printing-assisted personalized reconstructive surgery for blowout orbital fractures.

PURPOSE: One of the key challenges during orbital fracture reconstructive surgery, due to the complex anatomy of the orbit, is shaping and trimming the precise contour of the implants. The objectives of this study were to describe and evaluate the use of a three-dimensional (3-D) printing technique for personalized reconstructive surgery for repairing orbital fractures. METHODS: A total of 29 cases which had 3-D technique-assisted surgical reconstruction, and 27 cases which had traditional surgery, were retrospectively analyzed. Preoperative and postoperative CT images were measured using MIMICS software, and the contour of the fracture zone and the Medpor-titanium implant were analyzed and compared. The surgical duration was also compared between the two groups. RESULTS: There were statistically significant differences in the maximum width, depth and area between fracture zone and implant between the two groups, with the absolute value in the 3-D group markedly lower as compared to the control group. In addition, the difference in the medial-inferior wall angle between the surgical eye and healthy eye was also statistically significant between the groups. The average surgical duration in the 3-D group was substantially shorter than in the control group. Additionally, the postoperative clinical evaluation in the 3-D group was superior to that of the control group. CONCLUSION: The 3-D printing technique is of great value for predicting the precise fracture zone before, and during, personalized surgery, and can help surgeons achieve accurate anatomical reconstruction for repairs of blowout orbital fractures. Moreover, the simulated bone template produced by 3-D printing models allows for "true-to-original" orbital reconstruction, which can shorten the surgical duration and improve the accuracy and safety of the operation.

Metabolomic analysis for combined hepatotoxicity of chlorpyrifos and cadmium in rats.

Pesticides and heavy metals are widespread environmental pollutants. Although the acute toxicity of organophosphorus pesticide chlorpyrifos (CPF) and toxic heavy metal cadmium (Cd) is well characterized, the combined toxicity of CPF and Cd, especially the hepatotoxicity of the two chemicals with long-term exposure at a low dose, remained unclear. In this study, we investigated the toxicity in the liver of rats upon subchronic exposure to CPF and Cd at environmentally relevant doses. Rats were given three different doses (1/135 LD50, 1/45 LD50 and 1/15 LD50) of CPF and Cd as well as their mixtures by oral gavage for 90days. After treatment, the liver tissues were subjected to histopathological examination and biochemical analysis. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the metabolomic changes in the rat liver upon CPF, Cd and their mixtures treatment. The results showed that CPF and Cd-induced oxidative damage and disrupted energy, amino acid, and fatty acid metabolism in the liver. Eleven biomarkers in liver were identified for CPF-, Cd-, and their mixture-treated rats. Three metabolites, i.e., butanedioic acid, myo-inositol, and urea, were identified as unique biomarkers for the mixture-treated rats. Moreover, we found that Cd could accelerate the metabolism of CPF in the liver when given together to the rats, which may lead to the potential antagonistic interaction between CPF and Cd. In conclusion, our results indicated that even at environmentally relevant doses, CPF and Cd could disrupt the liver metabolism. In addition, the accelerated metabolism of CPF by Cd may lead to their potential antagonistic interaction.

Joint toxicity of chlorpyrifos and cadmium on the oxidative stress and mitochondrial damage in neuronal cells.

Pesticides and heavy metals can be easily biomagnified in food chains and bioaccumulated in individuals, thus pose significant threat to human health. However, their joint toxicity for long-term exposure at low dose has not been thoroughly investigated. In the present study, we investigated the oxidative damages in brain of rats exposed subchronically to organophosphorus pesticide chlorpyrifos (CPF) and heavy metal cadmium (Cd), and their mixtures at the environmentally relevant doses. Rats were given different doses of CPF and Cd by oral gavage for three months. After treatment, brain tissues were subjected for biochemical analysis. Mitochondrial damage and reactive oxidative species were also measured in neuroblastoma SH-SY5Y cells treated with CPF, Cd and their mixtures. The results showed that CPF and Cd generated protein and lipid peroxidation, disturbed the total antioxidant capability, and altered mitochondria ultrastructure in the brain. Lipids and proteins were sensitive to the oxidative damage induced by CPF and Cd. CPF and Cd decreased mitochondrial potential and induced reactive oxygen species in SH-SY5Y cells. However, the mixture did not display higher toxicity than the sum of that of the individual treatments. Thus, CPF and Cd could have a potential antagonistic interaction on the induction of oxidative stress.

Cadmium and chlorpyrifos inhibit cellular immune response in spleen of rats.

Cadmium (Cd) and chlorpyrifos (CPF) are common pollutants coexisting in the environment, and both of them have been reported to have immunotoxicity to organisms. However, the joint effects of these two chemicals on the immune system are still unknown. In this study, we used CdCl2 and CPF to study their combined effects on immune functions in the spleen of rats. In in vivo experiments, SD rats were exposed to different doses of CdCl2 (0.7 and 6 mg kg-1 body weight/day) and CPF (1.7 and 15 mg kg-1 body weight/day) or their combinations for consecutive 28 days. The proliferation and cytokine production ability of the splenocytes isolated from the treated animals were assessed. In in vitro experiments, we used different concentrations of CdCl2 and CPF to treat concanavalin A (Con A)-induced splenocytes isolated from untreated rats. We found that the combination of CPF and high dose of CdCl2 had a synergistic inhibitory effect on production of IFN-γ by spleen cells induced by Con A. The in vitro results showed that two chemicals had different effects on the cell proliferation and cytokine production depending on the exposure doses and time. This result suggests that exposure to both CdCl2 and CPF at the environmentally-relevant low dose may be potentially more hazardous than exposure to each individual toxicant.

Autophagy in Tri-o-cresyl Phosphate-Induced Delayed Neurotoxicity.

The widely used organophosphorus compound tri-o-cresyl phosphate (TOCP) elicits delayed neurotoxicity characterized by progressive axonal degeneration in the spinal cord and peripheral nerves. However, the precise mechanisms of TOCP-induced delayed neurotoxicity are not clear. Because autophagy has been linked to the pathogenesis of neurodegenerative diseases, we aimed to characterize autophagy in the progression of TOCP-induced delayed neurotoxicity. In vivo experiments using the adult hen animal model showed that autophagy in spinal cord axons and in sciatic nerves was markedly induced at the early preclinical stage of TOCP-induced delayed neurotoxicity; it was decreased as the delayed neurotoxicity progressed to the overt neuropathy stage. In cultured human neuroblastoma SH-SY5Y cells, TOCP reduced cell growth, and induced prominent autophagy. The autophagy inhibitor 3-methyladenine could attenuate TOCP-induced cytotoxicity, indicating that the autophagy is accountable for TOCP-induced neurotoxicity. In addition, we found that TOCP-induced Parkin translocation to mitochondria in SH-SY5Y cells, suggesting that autophagy may function to degrade mitochondria after TOCP exposure. These results suggest that autophagy may play an important role in the initiation and progression of axonal damage during TOCP-induced neurotoxicity.