ABSTRACT
Objective: To explore the protective effects of anthrahydroquinone-2,6-disulfonate (AH 2 QDS) on the kidneys of paraquat (PQ) poisoned rats via the apelin-APJ pathway. Methods: Male Sprague Dawley rats were divided into four experimental groups: control, PQ, PQ+sivelestat, and PQ+AH 2 QDS. The PQ+sivelestat group served as the positive control group. The model of poisoning was established via intragastric treatment with a 20% PQ pesticide solution at 200 mg/kg. Two hours after poisoning, the PQ+sivelestat group was treated with sivelestat, while the PQ+AH 2 QDS group was given AH 2 QDS. Six rats were selected from each group on the first, third, and seventh days after poisoning and dissected after anesthesia. The PQ content of the kidneys was measured using the sodium disulfite method. Hematoxylin-eosin staining of renal tissues was performed to detect pathological changes. Apelin expression in the renal tissues was detected using immunofluorescence. Western blotting was used to detect the expression levels of the following proteins in the kidney tissues: IL-6, TNF-α, apelin-APJ (the apelin-Angiotensin receptor), NF-κB p65, caspase-1, caspase-8, glucose-regulated protein 78 (GRP78), and the C/EBP homologous protein (CHOP). In in vitro study, a PQ toxicity model was established using human tubular epithelial cells treated with standard PQ. Twenty-four hours after poisoning, sivelestat and AH 2 QDS were administered. The levels of oxidative stress in human renal tubular epithelial cells were assessed using a reactive oxygen species fluorescence probe. Results: The PQ content in the kidney tissues of the PQ group was higher than that of the PQ+AH 2 QDS group. Hematoxylin-eosin staining showed extensive hemorrhage and congestion in the renal parenchyma of the PQ group. Vacuolar degeneration of the renal tubule epithelial cells, deposition of crescent-like red staining material in renal follicles, infiltration by a few inflammatory cells, and a small number of cast formation were also observed. However, these pathological changes were less severe in the PQ+sivelestat group and the PQ+AH 2 QDS group (P<0.05). On the third day after poisoning, immunofluorescence assay showed that the level of apelin in the renal tissues was significantly higher in the PQ+AH 2 QDS group than in the PQ group. Western blotting analysis results showed that IL-6, TNF-α, NF-κB p65, caspase-1, caspase-8, GRP78, and CHOP protein levels in the PQ group were higher than in the PQ+AH 2 QDS group (P<0.05). The expression of apelin-APJ proteins in the PQ+AH 2 QDS group was higher than in the PQ+sivelestat and PQ groups (P<0.05); this difference was significant on Day 3 and Day 7. The level of oxidative stress in the renal tubular epithelial cells of the PQ+AH 2 QDS group and the PQ+sivelestat group was significantly lower than in the PQ group (P<0.05). Conclusions: This study confirms that AH 2 QDS has a protective effect on PQ-poisoned kidneys and its positive effect is superior to that of sivelestat. The mechanism of the protective effects of AH 2 QDS may be linked to reduction in cellular oxidative stress, PQ content of renal tissue, inflammatory injury, endoplasmic reticulum stress, and apoptosis. AH 2 QDS may play a role in the treatment of PQ poisoning by upregulating the expression of the apelin-APJ.
ABSTRACT
Objective: To explore the protective effects of anthrahydroquinone-2,6-disulfonate (AH 2 QDS) on the kidneys of paraquat (PQ) poisoned rats via the apelin-APJ pathway. Methods: Male Sprague Dawley rats were divided into four experimental groups: control, PQ, PQ+sivelestat, and PQ+AH 2 QDS. The PQ+sivelestat group served as the positive control group. The model of poisoning was established via intragastric treatment with a 20% PQ pesticide solution at 200 mg/kg. Two hours after poisoning, the PQ+sivelestat group was treated with sivelestat, while the PQ+AH 2 QDS group was given AH 2 QDS. Six rats were selected from each group on the first, third, and seventh days after poisoning and dissected after anesthesia. The PQ content of the kidneys was measured using the sodium disulfite method. Hematoxylin-eosin staining of renal tissues was performed to detect pathological changes. Apelin expression in the renal tissues was detected using immunofluorescence. Western blotting was used to detect the expression levels of the following proteins in the kidney tissues: IL-6, TNF-α, apelin-APJ (the apelin-Angiotensin receptor), NF-κB p65, caspase-1, caspase-8, glucose-regulated protein 78 (GRP78), and the C/EBP homologous protein (CHOP). In in vitro study, a PQ toxicity model was established using human tubular epithelial cells treated with standard PQ. Twenty-four hours after poisoning, sivelestat and AH 2 QDS were administered. The levels of oxidative stress in human renal tubular epithelial cells were assessed using a reactive oxygen species fluorescence probe. Results: The PQ content in the kidney tissues of the PQ group was higher than that of the PQ+AH 2 QDS group. Hematoxylin-eosin staining showed extensive hemorrhage and congestion in the renal parenchyma of the PQ group. Vacuolar degeneration of the renal tubule epithelial cells, deposition of crescent-like red staining material in renal follicles, infiltration by a few inflammatory cells, and a small number of cast formation were also observed. However, these pathological changes were less severe in the PQ+sivelestat group and the PQ+AH 2 QDS group (P<0.05). On the third day after poisoning, immunofluorescence assay showed that the level of apelin in the renal tissues was significantly higher in the PQ+AH 2 QDS group than in the PQ group. Western blotting analysis results showed that IL-6, TNF-α, NF-κB p65, caspase-1, caspase-8, GRP78, and CHOP protein levels in the PQ group were higher than in the PQ+AH 2 QDS group (P<0.05). The expression of apelin-APJ proteins in the PQ+AH 2 QDS group was higher than in the PQ+sivelestat and PQ groups (P<0.05); this difference was significant on Day 3 and Day 7. The level of oxidative stress in the renal tubular epithelial cells of the PQ+AH 2 QDS group and the PQ+sivelestat group was significantly lower than in the PQ group (P<0.05). Conclusions: This study confirms that AH 2 QDS has a protective effect on PQ-poisoned kidneys and its positive effect is superior to that of sivelestat. The mechanism of the protective effects of AH 2 QDS may be linked to reduction in cellular oxidative stress, PQ content of renal tissue, inflammatory injury, endoplasmic reticulum stress, and apoptosis. AH 2 QDS may play a role in the treatment of PQ poisoning by upregulating the expression of the apelin-APJ.
ABSTRACT
Curcumin( Cur) is a natural active substance extracted from the roots or tubers of traditional Chinese medicinal materials. It has anti-inflammatory and anti-tumor activities on brain diseases. Due to the poor stability,low solubility,poor absorption and low bioavailability of curcumin,N-acetyl-L-cysteine( NAC) was used as an absorption enhancer and mixed with curcumin to improve the absorption of curcumin in the body. In this paper,curcumin was smashed by airflow pulverization,and Cur-NAC mixtures were prepared by being grinded with liquid. Then,the raw material and the product were analyzed by differential scanning calorimetry( DSC),X-ray diffraction( XRD) for structural characterization. The dissolution was determined by high performance liquid chromatography( HPLC) analysis. The characteristic peaks of the samples prepared by grinding method were similar to those of the raw materials,while the melting temperature and the accumulated dissolution degree were not significantly changed. The crystal forms of the products were not changed,and no new crystal form was formed after grinding. After the administration of intranasal powder,blood samples were collected from the orbit,while the whole brain tissues were removed from the skull and dissected into 10 anatomical regions. The concentrations of curcumin in these samples were determined by UPLC-MS/MS. The concentrations of curcumin in plasma and brain were compared at different time points. After intranasal administration of two drugs,it was found that the concentration of curcumin after sniffing up the mixtures in plasma was high,and the concentration of the drug in the olfactory bulb,hippocampus,and pons was increased significantly. Within 0. 083-0. 5 h,the olfactory bulb,piriform lobe and hippocampus remained high concentrations,the endodermis,striatum,hypothalamus and midbrain reached high concentrations within 1-3 h; and the cerebellum,pons and brain extension maintained relatively high concentrations within 3-7 h. The experiment showed that nasal administration of Cur-NAC mixtures can significantly improve the bioavailability of curcumin,and lead to significant differences in brain tissue distribution.