Combined effects of polystyrene nanoplastics and lipopolysaccharide on testosterone biosynthesis and inflammation in mouse testis.

Microplastics (MPs)/nanoplastics (NPs), as a source and vector of pathogenic bacteria, are widely distributed in the natural environments. Here, we investigated the combined effects of polystyrene NPs (PS-NPs) and lipopolysaccharides (LPS) on testicular function in mice for the first time. 24 male mice were randomly assigned into 4 groups, control, PS-NPs, LPS, and PS-NPs + LPS, respectively. Histological alterations of the testes were observed in mice exposed to PS-NPs, LPS or PS-NPs + LPS. Total sperm count, the levels of testosterone in plasma and testes, the expression levels of steroidogenic acute regulatory (StAR) decreased more remarkable in testes of mice treated with PS-NPs and LPS than the treatment with LPS or PS-NPs alone. Compared with PS-NPs treatment, LPS treatment induced more sever inflammatory response in testes of mice. Moreover, PS-NPs combined with LPS treatment increased the expression of these inflammatory factors more significantly than LPS treatment alone. In addition, PS-NPs or LPS treatment induced oxidative stress in testes of mice, but their combined effect is not significantly different from LPS treatment alone. These results suggest that PS-NPs exacerbate LPS-induced testicular dysfunction. Our results provide new evidence for the threats to male reproductive function induced by both NPs and bacterial infection in human health.

Enhancement of Peroxydisulfate Activation for Complete Degradation of Refractory Tetracycline by 3D Self-Supported MoS2/MXene Nanocomplex.

Antibiotic abuse, particularly the excessive use of tetracycline (TC), a drug with significant environmental risk, has gravely harmed natural water bodies and even posed danger to human health. In this study, a three-dimensional self-supported MoS2/MXene nanohybrid with an expanded layer spacing was synthesized via a facile one-step hydrothermal method and used to activate peroxydisulfate (PDS) for the complete degradation of TC. The results showed that a stronger •OH signal was detected in the aqueous solution containing MoS2/MXene, demonstrating a superior PDS activation effect compared to MoS2 or Ti3C2TX MXene alone. Under the conditions of a catalyst dosage of 0.4 g/L, a PDS concentration of 0.4 mM, and pH = 5.0, the MoS2/MXene/PDS system was able to fully eliminate TC within one hour, which was probably due to the presence of several reactive oxygen species (ROS) (•OH, SO4•-, and O2•-) in the system. The high TC degradation efficiency could be maintained under the influence of various interfering ions and after five cycles, indicating that MoS2/MXene has good anti-interference and reusability performance. Furthermore, the possible degradation pathways were proposed by combining liquid chromatography-mass spectrometry (LC-MS) data and other findings, and the mechanism of the MoS2/MXene/PDS system on the degradation process of TC was elucidated by deducing the possible mechanism of ROS generation in the reaction process. All of these findings suggest that the MoS2/MXene composite catalyst has strong antibiotic removal capabilities with a wide range of application prospects.

Prenatal diesel exhaust exposure alters hippocampal synaptic plasticity in offspring.

Diesel exhaust particles (DEPs) are major air pollutants emitted from automobile engines. Prenatal exposure to DEPs has been linked to neurodevelopmental and neurodegenerative diseases associated with aging. However, the specific mechanism by DEPs impair the hippocampal synaptic plasticity in the offspring remains unclear. Pregnant C57BL/6 mice were administered DEPs solution via the tail vein every other day for a total of 10 injections, then the male offsprings were studied to assess learning and memory by the Morris water maze. Additionally, protein expression in the hippocampus, including CPEB3, NMDAR (NR1, NR2A, NR2B), PKA, SYP, PSD95, and p-CREB was analyzed using Western blotting and immunohistochemistry. The alterations in the histomorphology of the hippocampus were observed in male offspring on postnatal day 7 following prenatal exposure to DEPs. Furthermore, 8-week-old male offspring exposed to DEPs during prenatal development exhibited impairments in the Morris water maze test, indicating deficits in learning and memory. Mechanistically, the findings from our study indicate that exposure to DEPs during pregnancy may alter the expression of CPEB3, SYP, PSD95, NMDAR (NR1, NR2A, and NR2B), PKA, and p-CREB in the hippocampus of both immature and mature male offspring. The results offer evidence for the role of the NMDAR/PKA/CREB and CPEB3 signaling pathway in mediating the learning and memory toxicity of DEPs in male offspring mice. The alterations in signaling pathways may contribute to the observed damage to synaptic structure and transmission function plasticity caused by DEPs. The findings hold potential for informing future safety assessments of DEPs.

TRPML1 contributes to antimony-induced nephrotoxicity by initiating ferroptosis via chaperone-mediated autophagy.

Evidence suggests that ferroptosis participates in kidney injury. However, the role of ferroptosis in antimony (Sb) induced nephrotoxicity and the mechanism are unknown. Here, we demonstrated that Sb induced injury in renal tubular epithelial cells (RTECs) and ferroptosis. Inhibition of ferroptosis reduced RTECs injury. Besides, elimination of reactive oxygen species (ROS) alleviated ferroptosis and RTECs injury. Moreover, exposure to Sb not only increased the co-localization of glutathione peroxidase 4 (GPX4) and LAMP1, but also decreased the levels of MEF2D and LRRK2, while increased the levels of HSC70, HSP90, and LAMP2a. These findings suggest that Sb activates chaperone-mediated autophagy (CMA), enhances lysosomal transport and subsequent degradation of GPX4, ultimately leads to ferroptosis. Additionally, up-regulation of lysosomal cationic channel, TRPML1, mitigated RTECs injury and ferroptosis. Mechanistically, up-regulation of TRPML1 mitigated the changes in CMA-associated proteins induced by Sb, diminished the binding of HSC70, HSP90, and TRPML1 with LAMP2a. Furthermore, NAC restored the decreased TRPML1 level caused by Sb. In summary, deficiency of TRPML1, secondary to increased ROS induced by Sb, facilitates the CMA-dependent degradation of GPX4, thereby leading to ferroptosis and RTECs injury. These findings provide insights into the mechanism underlying Sb-induced nephrotoxicity and propose TRPML1 as a promising therapeutic target.

Preventive effect of alkaline drinking water on hyperuricemia in mice / 预防医学

Objective@#To observe the preventive effect of alkaline drinking water on hyperuricemia in mice. @*Methods@#Sixty male SPF Kunming mice were randomly divided into six groups: pH 7.3, pH 8.0, pH 9.3 intervention groups, in which the mice were given water with pH values of 7.3±0.5, 8.0±0.5 and 9.3±0.6, respectively; the control group, model group and positive drug group ( with 2 g/L allopurinol ) were given double distilled water. Except for the control group, the mice in each group were given yeast by gavage (1.5 g/mL) for 13 days. On the 14th day, the mice were injected with 300 mg/kg potassium oxyzinate by intraperitoneal injection, and then fasted for 1 day. On the 16th day, serum uric acid, creatinine and urea nitrogen were detected, and renal tissues were stained to observe the morphology.The expression levels of neutrophil gelatinase-associated lipocalin ( NGAL ), tissue inhibitor of metalloproteinase 1( TIMP1 ), organic anion transporter 1 ( OAT1 ) and urate transporter 1 ( URAL-1 ) in renal tissues were determined bywestern blotting. The mRNA expression levels of URAL-1 and OAT1 were detected by real-time fluorescent quantita⁃tive polymerase chain reaction.@*Results@#The level of serum uric acid was higher in the model group than in the control group and in the pH 9.3 intervention group (both P<0.05). The number and area of renal tubular lesions were less in the pH 9.3 intervention group than in the model group (all P<0.05). The relative expression levels of NGAL and URAT-1 proteins were lower in the pH 9.3 intervention group than in the model group, and the relative expression level of OAT1 protein was higher in the pH 9.3 intervention group than in the model group ( all P<0.05). The relativeexpression level of URAT-1 mRNA was lower in the pH 9.3 intervention group than in the model group, and the rela⁃tive expression level of OAT1 mRNA was higher in the pH 9.3 intervention group than in the model group ( all P<0.05 ).@*Conclusion@#Alkaline drinking water with pH value of 9.3±0.6 can effectively prevent hyperuricemia and acute kidney injury in mice.