Targeted nanoparticles triggered by plaque microenvironment for atherosclerosis treatment through cascade effects of reactive oxygen species scavenging and anti-inflammation.

Inflammatory factors and reactive oxygen species (ROS) are risk factors for atherosclerosis. Many existing therapies use ROS-sensitive delivery systems to alleviate atherosclerosis, which achieved certain efficacy, but cannot eliminate excessive ROS. Moreover, the potential biological safety concerns of carrier materials through chemical synthesis cannot be ignored. Herein, an amphiphilic low molecular weight heparin- lipoic acid conjugate (LMWH-LA) was used as a ROS-sensitive carrier material, which consisted of injectable drug molecules used clinically, avoiding unknown side effects. LMWH-LA and curcumin (Cur) self-assembled to form LLC nanoparticles (LLC NPs) with LMWH as shell and LA/Cur as core, in which LMWH could target P-selectin on plaque endothelial cells and competitively block the migration of monocytes to endothelial cells to inhibit the origin of ROS and inflammatory factors, and LA could be oxidized to trigger hydrophilic-hydrophobic transformation and accelerate the release of Cur. Cur released within plaques further exerted anti-inflammatory and antioxidant effects, thereby suppressing ROS and inflammatory factors. We used ultrasound imaging, pathology and serum analysis to evaluate the therapeutic effect of nanoparticles on atherosclerotic plaques in apoe-/- mice, and the results showed that LLC showed significant anti-atherosclerotic effects. Our finding provided a promising therapeutic nanomedicine for the treatment of atherosclerosis.

Renal denervation alleviates renal ischemic reperfusion injury-induced acute and chronic kidney injury in rats partly by modulating miRNAs.

BACKGROUND: Renal denervation (RDN) has been used to promote kidney injury repair, whereas miRNAs have been found to be involved in the pathophysiology of renal injury. However, the miRNA alterations that occur after RDN and the related protective mechanisms remain to be determined. METHODS: Renal ischemic reperfusion injury (IRI) rat model was established and RDN was performed. Animals were killed at 24 h and 2 weeks following the operation. Tyrosine hydroxylase (TH) levels, renal function, tubular cell apoptosis and histological sections were examined at 24 h, whereas renal fibrosis and capillary vessels were assessed at 2 weeks. Furthermore, the expression of miRNAs in the injured kidney was determined using micro-array and the target genes were analyzed. RESULTS: We found that TH was eliminated and that renal function was improved in the denervation group at 24 h. RDN reduced tubular cell apoptosis and mitigated the histological lesion. Furthermore, an increase of capillary vessel density and reduction of renal fibrosis were observed after 2 weeks. Moreover, the numbers of miRNAs were up-regulated after RDN treatment, and the miRNAs targeted pro-angiogenic, anti-fibrotic and inflammatory pathways. CONCLUSIONS: RDN is a reliable method for alleviating IRI-induced acute and chronic kidney injury, and modulating the miRNA-related pro-angiogenic, anti-fibrotic or inflammatory pathways involved in this process.

Comprehensive miRNA Analysis of Human Umbilical Cord-Derived Mesenchymal Stromal Cells and Extracellular Vesicles.

BACKGROUND/AIMS: Mesenchymal stromal cells (MSCs) participate in the tissue-specific repair of many different organs, especially the kidney. Their effects are primarily mediated by the paracrine release of factors including extracellular vesicles (EVs), which are composed of micro-vesicles and exosomes. The corresponding microRNAs (miRNAs) of EVs are considered important for their biological functions. METHODS: MSCs were cultured from the human umbilical cord, and EVs were isolated from the medium. The expression levels of miRNAs in MSCs and EVs were determined by microarray analysis, and gene ontology (GO) was used to analyze the functions of their target genes. RESULTS: MSCs and EVs had similar miRNA expression profiles, with the exception of a small number of selectively enriched miRNAs. GO analysis indicated that, unlike MSCs, the target genes of EV-enriched miRNAs were associated with calcium channel regulation and cell junction activities, which may indicate that MSC and EVs have different regulatory properties. Angiogenesis, oxidative stress, and inflammatory signaling pathways related to the repair of renal injury were also analyzed, and EV-enriched miRNAs targeted genes associated with oxidative stress, T cell activation, and Toll-like receptor signaling. The miRNAs enriched in both MSCs and EVs targeted different genes in signaling pathways regulating angiogenesis and chemokine release. CONCLUSION: MSCs and their EVs shared similar miRNA component, and some selectively enriched miRNAs observed in MSCs and EVs may affect different target genes through some specific signaling pathways.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles Protect Against Acute Kidney Injury Through Anti-Oxidation by Enhancing Nrf2/ARE Activation in Rats.

BACKGROUND/AIMS: Anti-oxidation is an effective strategy for curing acute kidney injury (AKI). Herein, we suggest that extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) might play an anti-oxidative role by enhancing Nrf2/ARE activation in AKI. METHODS: EVs isolated from the conditioned medium of human Wharton's Jelly mesenchymal stromal cells and human foreskin fibroblast were intravenously injected in rats immediately after 45 min of unilateral kidney ischemia. Animals were sacrificed 24 h after injury. RESULTS: Results showed that renal tubular injury was alleviated and renal function was improved by MSC-EVs. Cell apoptosis and sNGAL levels, which reflect kidney cell injury, were reduced. Moreover, MSC-EVs decreased oxidative stress in injured kidney tissues and NRK-52E cells under hypoxia injury. Nrf2/antioxidant response element (ARE) enhancement and HO-1 up-regulation were further observed after MSC-EV treatment both in vivo and in vitro. CONCLUSIONS: MSC-EVs may protect against AKI possibly through anti-oxidation by enhancing Nrf2/ARE activation.

The regulation of inflammatory mediators in acute kidney injury via exogenous mesenchymal stem cells.

Acute kidney injury (AKI) remains to be an independent risk factor for mortality and morbidity. Inflammation is believed to play a major role in the pathophysiology of AKI. Exogenous mesenchymal stem cells (MSCs) are now under extensive investigation as a potential therapy for AKI. Various preclinical studies indicated the beneficial effects of MSCs in alleviating renal injury and accelerating tissue repair. However the mechanisms responsible for these effects are incompletely understood. In the recent years, anti-inflammatory/immunoregulatory properties of MSCs have become one of the important issues in the treatment of AKI. This review will summarize the current literature on the regulation of inflammatory mediators via exogenous MSCs contributing to the recovery from AKI.

Research on the steroidogenesis of proliferated Leydig cells in vitro.

Several treatments for patients with primary hypogonadism are available, but these are associated with major complications. In this study, we explored the possibility of testosterone secretion by proliferated Leydig cells embedded in Matrigel with the aim of developing a source of endogenous testosterone supplement for recipients while reducing the need for donor material. Leydig cells were isolated and proliferated in vitro. The expression of 3ß-hydroxysteroid dehydrogenase, cholesterol side-chain cleaving enzyme (CYP11A1), and 17α-hydroxylase/17,20-lyase (CYP17A1) was analyzed to confirm the purity and steroidogenesis capability of Leydig cells. The proliferated cells were then embedded in three-dimensional Matrigel, and following culture the supernatant medium was collected for measurement of testosterone concentration by radioimmunoassay. The biological behavior of the Leydig cells in the Matrigel was carefully observed under the microscope. Approximately 6.0 × 10(5) Leydig cells were obtained from one testis after primary culture in vitro. Aliquots of 1.0 × 10(5) Leydig cells were mixed with Matrigel, with the amount of cells in one pellet being equal to that in an adult testis. Leydig cells gradually formed aggregates when maintained in Matrigel. A rapid and constant linear increase in testosterone levels was detected in the supernatant medium. Our results demonstrate that Matrigel is a perfect support matrix for Leydig cells. Proliferated Leydig cells embedded in Matrigel have a great steroidogenesis reserve. In our study, they contributed to continuous steroidogenesis, which implies that the pellet may provide the physiological demand for endogenous androgen once engrafted in vivo. This system may ultimately provide a novel alternative treatment for people who are in need of androgen replacement.

Cofilin-1 induces acute kidney injury via the promotion of endoplasmic reticulum stress-mediated ferroptosis.

Ischemia-reperfusion injury (IRI) leads to acute kidney injury (AKI), which poses serious threat to public health and society. Many clinical studies were conducted to evaluate several biomarkers in AKI, among which Cofilin-1 remains to be a very promising one. To explore the potential mechanism of Cofilin-1 in AKI, we established an oxygen-glucose-deprivation (OGD)-induced AKI cell model. The overexpression and knock-down Cofilin-1 were used for gain- and loss-of-function. Pharmacological inhibitors were employed to study the related pathways. The results showed that Cofilin-1 was significantly upregulated in AKI cells, knocking down Cofilin-1 protected cells against the effect of OGD treatment and alleviated AKI phenotypes. Overexpression of Cofilin-1 might induce AKI by triggering ferroptosis, inhibiting NF-κB signaling or ER stress pathway attenuated Cofilin-1 induced lipid peroxidation and AKI. We also validated our findings in IRI-induced AKI mouse models in vivo. Our work elucidated that Cofilin-1 might induce AKI via promoting ER stress-mediated ferroptosis and argues it as a biomarker for early diagnosis of AKI. We also expect to offer novel insights on future therapeutic interventions.

A Bibliometric Analysis of Urologic Chronic Pelvic Pain Syndrome From 2000 to 2022.

Purpose: Urologic chronic pelvic pain syndrome has attracted a lot of attention in the new century, and an increasing number of relevant studies have been published. Therefore, we performed a bibliometric analysis of these publications, hoping to show the current research hotspots and future research trends. Methods: The articles on were selected from the Web of Science Core Collection. Countries, authors, references and keywords in the field were visualized and analyzed using CiteSpace and VOSViewer software. Results: A total of 1014 articles on urologic chronic pelvic pain syndrome were identified, with "chronic pelvic pain syndrome" being the most common keyword, with a strong association with "interstitial cystitis" and "chronic prostatitis". The hotspot of urologic chronic pelvic pain syndrome research has gradually shifted from chronic prostatitis / urologic chronic pelvic pain syndrome to cystitis/bladder pain syndrome over the past few years. Future research tends to focus on urologic chronic pelvic pain syndrome etiology, including oxidative stress and inflammation. Conclusion: Research on urologic chronic pelvic pain syndrome is steadily growing. The United States has made the most prominent contribution in this area, and the share of China's contribution is expected to grow further. The etiology of urologic chronic pelvic pain syndrome, including inflammation and oxidative stress, have been the focus of current research and developmental trends in the future research.

Alleviation of ischemia-reperfusion induced renal injury by chemically modified SOD2 mRNA delivered via lipid nanoparticles.

Ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury, which is a serious clinical condition with no effective pharmacological treatment. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) significantly alleviate kidney IRI; however, the underlying mechanisms and key molecules conferring renoprotection remain elusive. In this study, we characterized the protein composition of MSC-EVs using a proteomics approach and found that mitochondrial protein superoxide dismutase 2 (SOD2) was enriched in MSC-EVs. Using lipid nanoparticles (LNP), we successfully delivered chemically modified SOD2 mRNA into kidney cells and mice with kidney IRI. We demonstrated that SOD2 mRNA-LNP treatment decreased cellular reactive oxygen species (ROS) in cultured cells and ameliorated renal damage in IRI mice, as indicated by reduced levels of serum creatinine and restored tissue integrity compared with the control mRNA-LNP-injected group. Thus, the modulation of mitochondrial ROS levels through SOD2 upregulation by SOD2 mRNA-LNP delivery could be a novel therapeutic method for ischemia-reperfusion-induced acute kidney injury.

The alleviation of acute and chronic kidney injury by human Wharton's jelly-derived mesenchymal stromal cells triggered by ischemia-reperfusion injury via an endocrine mechanism.

BACKGROUND AIMS: The effects of human Wharton's jelly-derived mesenchymal stromal cells (WJ-MSC) on acute and chronic kidney injury induced by ischemia-reperfusion injury (IRI) were assessed. METHODS: WJ-MSC were injected intravenously immediately after solitary kidney ischemia for 45 min. Cells were labeled with 5-bromo-2'deoxy-uridine (BrdU) for tracing in vivo. At 48 h post-IRI, serum creatinine and blood urea nitrogen (BUN) were measured. Tubular cell proliferation and apoptosis as well as activation of the Akt signal were identified by immunostaining. Real-time polymerase chain reaction (PCR) was employed to determine gene expression of inflammation-related cytokines and hepatocyte growth factor (HGF). Levels of human HGF were assayed by enzyme-linked immunosorbant assay (ELISA). Twenty-two weeks later, renal fibrosis was assessed by Masson's tri-chrome staining, collagen content and α-smooth muscle actin (α-SMA) staining. RESULTS: There was no sign of labeled cells residing in the damaged kidney. Acute renal dysfunction elicited by IRI was considerably improved by WJ-MSC, in parallel with a stronger proliferative response and less apoptotic events. Additionally, phosphoAkt staining in injured tubular cells was substantially intensified. Cell treatment also caused a remarkable up-regulation of kidney interleukin (IL)-10, heme oxygenase (HO)-1 and HGF expression. Human HGF was detected in cell supernatants and the serum of cell-infused rats. Moreover, IRI-initiated fibrosis was abrogated by cell therapy, coincident with function amelioration. CONCLUSIONS: WJ-MSC alleviate acute kidney injury, thereby rescuing the ensuing fibrotic lesions in an endocrine manner. The Akt signal in impaired tubular cells is reinforced by WJ-MSC, facilitating cell resistance to apoptosis and cell proliferation. HGF, either delivered or induced by WJ-MSC, is an important contributor.

Tubularized urethral replacement using tissue-engineered peritoneum-like tissue in a rabbit model.

INTRODUCTION: This study aims to investigate whether mesothelial cells could function as seed cells to construct tissue-engineered peritoneum-like tissue for urethral reconstruction in a rabbit model. MATERIALS AND METHODS: Bladder acellular matrices were prepared and trimmed to 1.5 × 1 cm. Nine male rabbits underwent omentum biopsy and autologous mesothelial cells were isolated. After in vitro expansion, the cells were seeded onto the matrices and incubated for 7 days. In 18 rabbits, a pendulous urethral segment 1.5 cm long was totally excised and urethroplasty was performed with tubularized matrices seeded with cells in 9 animals and without cells in 9 as controls. Urethrography was performed at 1, 2 and 6 months postoperatively. Meanwhile, the neourethras were harvested and analyzed grossly and histologically. RESULTS: Histological analysis of the cell-seeded grafts revealed a loose collagen matrix covered with a single layer of mesothelim. Serial urethrography indicated a wide urethral caliber without stricture formation in animals implanted with cell-seeded matrices, while all animals of the control group developed stricture. Histological analysis of the implanted cell-seeded matrices demonstrated a normal urethral architecture by 1 month, composed of multilayers of urothelium surrounded by smooth muscle bundles, which became increasingly organized with time. By 6 months, the neourethra could be hardly distinguished from native urethra both grossly and histologically. CONCLUSIONS: Autologous mesothelial cells could be successfully used as seed cells for tubularized urethral reconstruction in male rabbits.

Ureteral reconstruction using autologous tubular grafts for the management of ureteral strictures and defects: an experimental study.

OBJECTIVE: To investigate whether the peritoneal cavity could function as a bioreactor to produce autologous tubular grafts for ureteral reconstruction in beagles. MATERIALS AND METHODS: 8-Fr Silastic tubes were implanted into the peritoneal cavities of 6 female beagles. At 3 weeks, the tubes were harvested and the tubular tissue covering the tubes was gently everted. A segment 3 cm in length of the right mid-ureter, involving two thirds of its diameter, was removed parallel to the ureteral axis, leaving a third of the ureteral wall. A 5-Fr double-J stent was inserted into the ureter through the created defect, and two thirds of the graft were anastomosed to both edges of the ureteral defect. One third of the graft was overlapped with the retained normal ureter and anastomosed to the external surface of the lumens. Thus, the graft was partly encapsulated by the remainder of ureteral wall. The stent was maintained for 6 weeks and removed. Excretory urography was performed at 8 (n = 3) and 12 weeks (n = 3), postoperatively. Meanwhile, the neoureter was harvested and analyzed. The left ureter served as the control and a simple intubated ureterotomy was performed. RESULTS: Histological analysis of the tubular tissue demonstrated transversely arranged myofibroblasts and an outer layer of mesothelium. The tissue was easily everted and transplanted as a ureteral graft. Eight weeks postoperatively, the neoureter demonstrated normal ureteral architecture, composed of multilayers of urothelium surrounded by smooth muscle bundles, which became increasingly organized with time. Excretory urography indicated no stenosis or hydronephrosis. CONCLUSIONS: These results show that autologous tubular tissue grown within the recipients' peritoneal cavity can be used for ureteral reconstruction in the beagle model.

Research on the isolation of mouse Leydig cells using differential digestion with a low concentration of collagenase.

The aim of this study was to establish a novel method for isolating and purifying Leydig cells from mice testes. Testes of postpuberal mice were harvested and digested in a low concentration of collagenase NB4 for 15 min 2 times. Cells obtained were cultured in low glucose DMEM with 10% FBS. Immunofluorescence was used to detect the expression of Leydig cell biomarkers including 3ß-hydroxysteroid dehydrogenase, cholesterol side-chain cleaving enzyme (CYP11A1) and 17α-hydroxylase/17,20-lyase (CYP17A1). It was found that the purity of the isolated Leydig cells was 69.6 ± 4.16%. After 7 days in primary culture, it increased to 90%. The testosterone synthase spectrum could be detected at the primary culture. In conclusion, the application of a low concentration of collagenase for differential digestion allows isolation of large quantities of viable Leydig cells.

MiR-197 Inhibitor Loaded AbCD133@MSNs@GNR Affects the Development of Prostate Cancer Through Targeting ITGAV.

Prostate cancer is one of the most severe male malignant tumors, which ranks second in mortality rate among all tumors. Traditional methods of treatment for prostate cancer produce obvious side effects and a high recurrence rate. Cancer stem cells are considered to be a group of cells that determine the proliferation, metastasis, and drug resistance of tumor. Prostate cancer therapy based on microRNAs and prostate cancer stem cells (PCSCs) has been a research hot spot in this field. Previous studies have reported that miR-197 plays an important role in the occurrence and development of prostate cancer, but the molecular mechanism of miR-197 on the development of prostate cancer has not been reported yet. In this study, we verified that miR-197 is significantly overexpressed in prostate cancer tissues and prostate cancer cells. Then, we verified that miR-197 expression affects the proliferation, invasion, and metastasis of prostate cancer cells by regulating integrin subunit alpha V (ITGAV) expression through STAT5 pathway, and the results indicated that the miR-197 inhibitor can be a prostate cancer suppressor. Then we synthesized the AbCD133@GNR@MSNs@miR-197 inhibitor drug carrier, in which 35.42 µg of the miR-197 inhibitor could be loaded in 1 mg of AbCD133@GNR@MSNs. The AbCD133@GNR@MSNs@miR-197 inhibitor demonstrated good photothermal properties and photothermal controlled-release properties. The modified CD133 antibodies on the surface of the nano drug carrier helped more drug carriers to enter the PCSCs. The pharmacodynamic effects of the AbCD133@GNR@MSNs@miR-197 inhibitor on PCSCs in vivo and in vitro were studied under near-infrared radiation. The results showed that the AbCD133@GNR@MSNs@miR-197 inhibitor prepared in this study could not only significantly suppress the development of PCSCs through ITGAV/STAT5 pathway but also significantly suppress the growth of PCSC solid tumors. In short, our study verified that miR-197 regulates the development of PCSCs through STAT5 pathway by targeting ITGAV, and the AbCD133@MSNs@GNR@miR-197 inhibitor could be a potential suppressor used in prostate cancer treatment. In short, our study found that miR-197 affected the development of prostate cancer by regulating ITGAV. The AbCD133@GNR@MSNs@miR-197 inhibitor prepared in this study could suppress the development and growth of PCSCs in vitro and in solid tumors not only by targeting the ITGAV but also through photothermal therapy. Our study not only provides a theoretical basis for the clinical treatment of prostate cancer but also provides a research scheme of drug loading and microRNA-based photothermal controlled therapy for prostate cancer.

Non-apoptotic function of caspase-8 confers prostate cancer enzalutamide resistance via NF-κB activation.

Caspase-8 is a unique member of caspases with a dual role in cell death and survival. Caspase-8 expression is often lost in some tumors, but increased in others, indicating a potential pro-survival function in cancer. By analyzing transcriptome of enzalutamide-resistant prostate cancer cells, we found that resistance was conferred by a mild caspase-8 upregulation that in turn led to NF-κB activation and the subsequent upregulation of the downstream IL-8. Mechanistically, we found that the pro-survival and enzalutamide-resistance-promoting features of caspase-8 were independent of its proteolytic activity, using a catalytically-inactive caspase-8 mutant. We further demonstrated that caspase-8 pro-apoptotic function was inhibited via cFLIP binding. Moreover, high caspase-8 expression was correlated with a worse prognosis in prostate cancer patients. Collectively, our work demonstrates that enzalutamide-resistance is mediated by caspase-8 upregulation and the consequent increase in NF-κB/IL-8 mediated survival signaling, highlighting caspase-8 and NF-κB as potential therapeutic targets to overcome enzalutamide-resistance in CRPC.

Peritoneal cavity as bioreactor to grow autologous tubular urethral grafts in a rabbit model.

PURPOSE: To investigate whether peritoneal cavity could function as bioreactor to produce autologous tubular grafts for urethral reconstruction in male rabbits. METHODS: 8Fr silastic tubes were implanted into peritoneal cavities of nine male rabbits. By 2 weeks, tubes were harvested and the tubular tissue covering the tubes was everted. A pendulous urethral segment of 1.5 cm long was totally excised and urethroplasty was performed with the everted tubular tissue in an end-to-end fashion. Another nine male rabbits underwent the same urethral resection and re-anastomosis as controls. Urethrography was performed at 1, 2 and 6 months postoperatively. Meanwhile, the neo-urethra were harvested and analyzed grossly and histologically. RESULTS: Histological analysis of the tubular tissue demonstrated transversely arranged myofibroblasts embedded in homogeneous collagen bundles and an outer layer of mesothelium. The tissue was easily everted and successfully transplanted as a urethral graft. Serial urethrography indicated no stricture or diverticula formation. While all animals of the control group developed stricture. Histological analysis of the neo-urethra demonstrated normal urethral architecture by 1 month, composed of multi-layers of urothelium surrounded by smooth muscle bundles, which became increasingly organized with time. By 6 months, the neo-urethra could be hardly distinguished from native urethra both grossly and histologically. CONCLUSIONS: These results show that the autologous tissue grown within the recipients' peritoneal cavity can be used successfully for tubularized urethral reconstruction in male rabbits.

Effects of acrylamide on the nervous tissue antioxidant system and sciatic nerve electrophysiology in the rat.

To investigate the time-dependent effects of acrylamide (ACR) on the antioxidative status in rat nerve tissues, adult male Wistar rats were given ACR (40 mg/kg, i.p., 3 times/week) for 2, 4, 6 and 10 weeks, respectively. The time-dependent changes of the lipid peroxidation (malondialdehyde, MDA) and antioxidative status (glutathione, GSH; glutathione peroxidase, GSH-Px; glutathione reductase, GR; superoxide dismutase, SOD and anti-reactive oxygen species, anti-ROS) in nerve tissues were investigated. The electrophysiology indices (nerve conduction velocity, NCV; compound action potential duration, CAPD; compound action potential amplitude, CAPA; compound action potential latency, CAPL) in the sciatic nerve were determined using BL-420E Biologic Function Determining System. The results showed that MDA levels increased significantly (P < 0.05) in nerve tissues, while GSH levels markedly decreased (P < 0.05) in a time-dependent manner. SOD activity (in the spinal cord and sciatic nerve) and GR activity (in the sciatic nerve) increased significantly after 4 weeks ACR treatment (P < 0.01), but then decreased (P < 0.05). The anti-ROS activity in the sciatic nerve was markedly decreased at the end of week 6 and 10 (P < 0.01). The above indices changed most in the sciatic nerve. The levels of GSH, MDA and anti-ROS in rat sciatic nerve were in high correlation (P < 0.05, |r| > 0.80) with the electrophysiology indices according to the exposure time. Thus, ACR-induced neurotoxicity may be associated with the enhancement of lipid peroxidation and reduction of the antioxidative capacity. Depletion of neural GSH level might be one of the primary events in ACR-induced neuropathy.

Time-dependent changes of lipid peroxidation and antioxidative status in nerve tissues of hens treated with tri-ortho-cresyl phosphate (TOCP).

Tri-ortho-cresyl phosphate (TOCP) could induce a delayed neurodegenerative condition known as organophosphorus easter-induced delayed neurotoxicity (OPIDN) in human beings and sensitive animals. However, the mechanisms of OPIDN remain unknown. This study investigated the time-dependent changes of the lipid peroxidation (malondialdehyde, MDA) and antioxidative status (glutathione, GSH; glutathione peroxidase, GSH-Px; glutathione reductase, GR; superoxide dismutase, SOD and anti-reactive oxygen species, anti-ROS) in nerve tissues for elucidating the mechanism of OPIDN induced by TOCP. Adult hens were treated with TOCP by gavage at a single dosage of 750 mg/kg. TOCP was dissolved in corn oil and administered at 0.65 ml/kg. The control hens received an equivalent volume of corn oil by gavage. Hens were sacrificed after 0, 5, 10, 15 and 21 days of treatment and the cerebrum, spinal cord, sciatic nerve were dissected, homogenized and used for the determination of lipid peroxidation and antioxidative status. The results showed that treatment with TOCP increased lipid peroxidation and reduced the antioxidative status in cerebrum, spinal cord and sciatic nerve. The levels of MDA increased by 33% (P<0.01) in cerebrum on 5th day after TOCP treatment and at clinical sign score of 1-2, and increased respectively by 32% and 15% (P<0.01) in spinal cord and sciatic nerve on 10th day after TOCP treatment and at clinical sign score of 3-4. Further changes of MDA were also observed after 15 and 21 days post-dosing and at clinical sign score of 5-6 and 7-8. There is a decrease in the activities of SOD, GSH-Px, GR, anti-ROS, and GSH content in cerebrum, spinal cord and sciatic nerve of hens after 5, 10, 15 and 21 days post-dosing and at clinical sign score of 1-2, 3-4, 5-6 and 7-8. Thus, OPIDN induced by TOCP was associated with elevation of lipid peroxidation and reduction of antioxidative status, and the time-dependent changes of these indexes in hens nerve tissues occurred. Sciatic nerve was the main target tissue and MDA was most sensitive among all indexes. The time-dependent and tissue specific changes of lipid peroxidation and antioxidative status in cerebrum, spinal cord and sciatic nerve suggest that ROS and concomitant lipid peroxidation, at least in part, are involved in the toxic effects of TOCP on nerve tissues and that oxidative stress may play a role in the occurrence and development of OPIDN induced by TOCP.

[In vivo and in vitro determination of changes of electrophysiology in rats with allyl chloride poisoning].

OBJECTIVE: To compare the results of in vivo and in vitro in determination of the changes of allyl chloride (AC)-induced electrophysiology in rats sciatic nerve. METHODS: Ninety male Wistar rats weighted 180 approximately 220 g were divided randomly into two groups, i.e. experimental group (n=40) and control group (n=50). The rats in experimental group were treated with AC dissolved in corn oil (200 mg/kg ip 3 days/week) by gavage for 12 weeks. Electrophysiological indexes of each group were determined on 3, 6, 9 and 12 weeks of AC intoxication. The indexes included measurements of sciatic nerve conduct velocity (NCV), compound action potential amplitude (CAPA), potential latency (PL), time course (TC), threshold potential (TP) and max stimulate potential (MSP). RESULTS: Compared to the corresponding time-matched control rats, on 6, 9 and 12 weeks of AC intoxication, NCV were decreased by 23.6%, 40.4% and 48.6% (P<0.05, P<0.01) in vivo, while in vitro it was decreased by 15.4% (P<0.05) on 12 week, CAPA were reduced by 31.7% in vivo, while in vitro it was reduced by 31.7%, 38.9% and 58.9% (P<0.05, P<0.01), respectively, PL were prolonged 22.6% and 40.7% (P<0.01) on 9, 12 weeks in vivo, while in vitro it was prolonged 8.0% (P<0.05), TC were increased 22.5%, 34.6% and 47.5% (P<0.01) in vivo, while in vitro it was increased 11.6%, 20.0% (P>0.05) and 19.5% (P<0.01), respectively, TP were elevated 12.1% (P>0.05), 32.3% and 40.0% (P<0.05) in vivo, while in vitro it was elevated 16.4% (P>0.05), 29.2% and 35.6% (P<0.05), respectively, MSP were increased 40.5% (P>0.05), 69.0% and 86.5% (P<0.01) in vivo, while in vitro it was increased 29.7% (P>0.05), 52.0% and 61.9% (P<0.01), respectively. CONCLUSION: The two methods of in vivo and in vitro showed that AC could significantly affect the electrophysiology of sciatic nerve, and the time-dependent changes occurred. The NCV is the most sensitive indicator in vivo to the early diagnosis of AC intoxication, while CAPA is the most sensitive indicator in vitro.