Reactive oxygen species (ROS) are major contributors to radiation therapy-induced side effects in cancer patients. A fusion antioxidant enzyme comprising glutathione S-transferase (GST), superoxide dismutase 1 (SOD1), and a transmembrane peptide has been shown to effectively mitigate ROS-induced damage. To enhance its targeting capability, the fusion protein was further modified by incorporating a matrix metalloproteinase-2/9 substrate peptide (X) and the transmembrane peptide R9, yielding the antioxidant enzyme GST-SOD1-X-R9 (GS1XR). This modification reduced its transmembrane ability in tumor cells, thereby selectively protecting normal cells from oxidative stress. However, the use of non-human GST poses potential immunogenicity risks. In this study, we employed seamless cloning technology to construct an expression vector containing the human GST gene to replace the non-human GST gene, and then expressed and purified novel fusion antioxidant enzymes GS1R and GS1XR. The protective effects of newly constructed GS1R and GS1XR against hydrogen peroxide (H₂O₂)-induced oxidative damage in L-02 cells were then evaluated using GS1 as a control. Enzymatic activity assays revealed that the specific activity of GST in GS1XR remained unchanged compared to the unmodified protein, while SOD activity was enhanced. Exposure to 200 μmol/L H₂O₂ transiently activated the nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway; however, this activation diminished after 24 h, reducing cell viability to 48.4%. Both GS1R and GS1XR effectively scavenged intracellular ROS, directly counteracting oxidative stress and promoting Nrf2 nuclear translocation, thereby activating antioxidant pathways and restoring cell viability to normal levels. The two enzymes showed comparable efficacy. In contrast, GS1, lacking transmembrane capability, was restricted to scavenging extracellular ROS and provided only limited protection. In conclusion, both novel fusion antioxidant enzymes demonstrated significant potential in safeguarding normal cells from ROS-mediated oxidative damage. The findings provide a foundation for further investigation in related field.
Humans ; Oxidative Stress/drug effects* ; Hydrogen Peroxide ; Antioxidants/metabolism* ; Glutathione Transferase/metabolism* ; Recombinant Fusion Proteins/pharmacology* ; Superoxide Dismutase-1 ; Reactive Oxygen Species/metabolism* ; Superoxide Dismutase/biosynthesis*

Objective To explore the mechanism of electroacupuncture in alleviating hyperlipidemia in a rat model by modulating mammalian target of rapamycin complex 1(mTORC1)-mediated lipophagy in hepatocytes.Methods A total of 30 SD rats were randomly divided into blank(n=6)and modeling groups(n=24)using the random number table method.A hyperlipidemic rat model was established by feeding rats a high-fat diet(feeding for 8 weeks).After successful modeling,the modeling group was randomly divided into the model,electroacupuncture,mTORC1 inhibitor,and electroacupuncture+mTORC1 agonist groups,with six rats in each group.Except for the blank group,all other rats were fed with high fat diet.Rats in the electroacupuncture and electroacupuncture+mTORC1 agonist groups received electroacupuncture intervention at bilateral"Fenglong"(ST40)acupoints(dilatational wave 2 Hz/100 Hz,current intensity 1 mA)for 30 min once daily.Rats in the mTORC1 inhibitor group received intraperitoneal injections of the mTORC1 inhibitor,rapamycin(2 mg/kg),once daily.Rats in the electroacupuncture+mTORC1 agonist group received intraperitoneal injections of the mTORC1 agonist MHY1485(10 mg/kg)once daily.The interventions were administered for five consecutive days per week for 4 weeks.Upon completion of the intervention,the following analyses were performed:serum contents of total cholesterol(TC),triglycerides(TAG),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),free fatty acids(FFA),alanine aminotransferase(ALT),and aspartate aminotransferase(AST)were measured using a fully automated biochemical analyzer.Hepatic histopathological changes and lipid deposition were observed using hematoxylin-eosin and oil red O staining.The liver condition was observed and the liver index was calculated.Hepatic TC and TAG levels were measured using an enzyme-linked immunosorbent assay.The ultrastructure of the liver tissue was observed using transmission electron microscopy,and the mean fluorescence intensity of perilipin 2(PLIN2)and microtubule-associated protein 1 light chain 3(LC3)-Ⅱ in the liver tissue was detected using immunofluorescence.Protein expression of LC3-Ⅱ/LC3-Ⅰ,phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR,and mTORC1 in liver tissue was detected using Western blotting.Results Compared to the blank group,the model group rats showed increased serum TC,TAG,LDL-C,ALT,AST,and FFA levels,along with decreased HDL-C levels(P<0.05).The liver index and hepatic TC and TAG levels were also elevated(P<0.05).Histological examination of liver tissue revealed substantial lipid accumulation,numerous lipid droplets within hepatocytes,abnormal mitochondrial morphology,and scarce autophagic vacuole.The mean fluorescence intensity of PLIN2 increased,whereas that of LC3-Ⅱ decreased(P<0.05).Additionally,the LC3-Ⅱ/LC3-Ⅰ ratio was reduced,whereas the p-mTOR/mTOR ratio and mTORC1 protein expression were increased(P<0.05).Compared to the model group,rats in the mTORC1 inhibitor and electroacupuncture groups exhibited decreased serum TC,TAG,LDL-C,ALT,AST,and FFA levels(P<0.05),along with a reduced liver index and hepatic TC and TAG levels(P<0.05).Histological examination showed markedly attenuated lipid accumulation and visible autophagic vacuole in the hepatocytes.The mean fluorescence intensity of PLIN2 decreased,whereas that of LC3-Ⅱ increased(P<0.05).Moreover,the LC3-Ⅱ/LC3-Ⅰ ratio increased,whereas the p-mTOR/mTOR ratio and mTORC1 protein expression decreased(P<0.05).In comparison with both the electroacupuncture and mTORC1 inhibitor groups,the electroacupuncture+mTORC1 agonist group demonstrated increased serum TAG,TC,LDL-C,ALT,AST,and FFA levels(P<0.05)as well as elevated liver index and hepatic TC and TAG levels(P<0.05).Liver tissues exhibited aggravated lipid deposition and absence of autophagic vacuole in liver cells.The mean fluorescence intensity of PLIN2 was enhanced,whereas that of LC3-Ⅱ was reduced(P<0.05).Furthermore,the LC3-Ⅱ/LC3-Ⅰ ratio decreased,and the p-mTOR/mTOR ratio and mTORC1 protein expression increased(P<0.05).Conclusion Electroacupuncture at"Fenglong"(ST40)may improve blood lipid levels in hyperlipidemic rats by inhibiting mTORC1 and promoting hepatocyte lipophagy.

Objective To explore the mechanism of electroacupuncture in alleviating hyperlipidemia in a rat model by modulating mammalian target of rapamycin complex 1(mTORC1)-mediated lipophagy in hepatocytes.Methods A total of 30 SD rats were randomly divided into blank(n=6)and modeling groups(n=24)using the random number table method.A hyperlipidemic rat model was established by feeding rats a high-fat diet(feeding for 8 weeks).After successful modeling,the modeling group was randomly divided into the model,electroacupuncture,mTORC1 inhibitor,and electroacupuncture+mTORC1 agonist groups,with six rats in each group.Except for the blank group,all other rats were fed with high fat diet.Rats in the electroacupuncture and electroacupuncture+mTORC1 agonist groups received electroacupuncture intervention at bilateral"Fenglong"(ST40)acupoints(dilatational wave 2 Hz/100 Hz,current intensity 1 mA)for 30 min once daily.Rats in the mTORC1 inhibitor group received intraperitoneal injections of the mTORC1 inhibitor,rapamycin(2 mg/kg),once daily.Rats in the electroacupuncture+mTORC1 agonist group received intraperitoneal injections of the mTORC1 agonist MHY1485(10 mg/kg)once daily.The interventions were administered for five consecutive days per week for 4 weeks.Upon completion of the intervention,the following analyses were performed:serum contents of total cholesterol(TC),triglycerides(TAG),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),free fatty acids(FFA),alanine aminotransferase(ALT),and aspartate aminotransferase(AST)were measured using a fully automated biochemical analyzer.Hepatic histopathological changes and lipid deposition were observed using hematoxylin-eosin and oil red O staining.The liver condition was observed and the liver index was calculated.Hepatic TC and TAG levels were measured using an enzyme-linked immunosorbent assay.The ultrastructure of the liver tissue was observed using transmission electron microscopy,and the mean fluorescence intensity of perilipin 2(PLIN2)and microtubule-associated protein 1 light chain 3(LC3)-Ⅱ in the liver tissue was detected using immunofluorescence.Protein expression of LC3-Ⅱ/LC3-Ⅰ,phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR,and mTORC1 in liver tissue was detected using Western blotting.Results Compared to the blank group,the model group rats showed increased serum TC,TAG,LDL-C,ALT,AST,and FFA levels,along with decreased HDL-C levels(P<0.05).The liver index and hepatic TC and TAG levels were also elevated(P<0.05).Histological examination of liver tissue revealed substantial lipid accumulation,numerous lipid droplets within hepatocytes,abnormal mitochondrial morphology,and scarce autophagic vacuole.The mean fluorescence intensity of PLIN2 increased,whereas that of LC3-Ⅱ decreased(P<0.05).Additionally,the LC3-Ⅱ/LC3-Ⅰ ratio was reduced,whereas the p-mTOR/mTOR ratio and mTORC1 protein expression were increased(P<0.05).Compared to the model group,rats in the mTORC1 inhibitor and electroacupuncture groups exhibited decreased serum TC,TAG,LDL-C,ALT,AST,and FFA levels(P<0.05),along with a reduced liver index and hepatic TC and TAG levels(P<0.05).Histological examination showed markedly attenuated lipid accumulation and visible autophagic vacuole in the hepatocytes.The mean fluorescence intensity of PLIN2 decreased,whereas that of LC3-Ⅱ increased(P<0.05).Moreover,the LC3-Ⅱ/LC3-Ⅰ ratio increased,whereas the p-mTOR/mTOR ratio and mTORC1 protein expression decreased(P<0.05).In comparison with both the electroacupuncture and mTORC1 inhibitor groups,the electroacupuncture+mTORC1 agonist group demonstrated increased serum TAG,TC,LDL-C,ALT,AST,and FFA levels(P<0.05)as well as elevated liver index and hepatic TC and TAG levels(P<0.05).Liver tissues exhibited aggravated lipid deposition and absence of autophagic vacuole in liver cells.The mean fluorescence intensity of PLIN2 was enhanced,whereas that of LC3-Ⅱ was reduced(P<0.05).Furthermore,the LC3-Ⅱ/LC3-Ⅰ ratio decreased,and the p-mTOR/mTOR ratio and mTORC1 protein expression increased(P<0.05).Conclusion Electroacupuncture at"Fenglong"(ST40)may improve blood lipid levels in hyperlipidemic rats by inhibiting mTORC1 and promoting hepatocyte lipophagy.

Objective:To explore the clinical and imaging characteristics of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) caused by mitochondrial DNA 14453G>A (m.14453G>A) mutation.Methods:A case of MELAS caused by m.14453G>A mutation in the First Affiliated Hospital of Harbin Medical University on October 12, 2021 was reported. At the same time, the reported cases of MELAS and Leigh syndrome (LS) caused by the m.14453G>A mutation were reviewed. This enabled a comprehensive summarization, analysis, and comparison of these cases.Results:The patient was a female. She has suffered from the disease since 13-year old with seizures, accompanied by the disturbance of mood and the loss of memory. Brain magnetic resonance imaging findings consisted of lesions in frontal, parietal, occipital, temporal lobe and cerebellar. The patient was initially considered with autoimmune encephalitis and posterior reversible encephalopathy syndrome. Since direct sequencing of the complete mitochondrial genome from blood of the patient revealed m.14453G>A mutation in ND6 gene, and the mutation rate was 17.0%, the patient eventually diagnosed with MELAS based on clinical manifestations, imaging examinations, and genetic testing results. Using "m.14453G>A" as the search term, the relevant literature in China and abroad was retrieved and those with complete clinical data were identified. A total of 11 cases of m.14453G>A mutation including this case were reported, of whom 5 patients were diagnosed as MELAS, and 6 patients were diagnosed as LS. Among the 11 patients, those being adolescent or adult and with lesions in the cortex and subcortical white matter were probably be MELAS; those being infant or young child and with lesions in basal ganglia, thalamus and brainstem could be LS. Conclusions:Mitochondrial disease caused by m.14453G>A gene mutation shows a great heterogeneity, which can cause MELAS and LS. The clinical phenotype of the m.14453G>A mutation may be related to the age of onset and lesion′ s location.

Objective To explore the effects of secreted apoptosis-related protein 1 (SARP1) on apoptosis of the hyperstrophic scar fibroblasts (HSFB) and its regulating mechnisms.Methods The recombinant vector was identified by enzyme digestion analysis.And the virus supernatant of the recombinant vector was extracted from packaged 293 cells,then it infected the skin fibroblasts from hypertrophic scar patients,which aimed to promote its expression of SARP1 protein.After adenovirus infection,the expression of SARP1 in the fibroblasts was confirmed by RT-PCR and Western blot.The effect of SARP1 on proliferation of HSFB was detected by MTT assay,and the effect of SARP1 on apoptosis of HSFB was detected and change of the cells functions were analyzed by FACS.Results Recombinants were confirmed.After adenovirus infection,both protein and mRNA of SARP1 were detected in HSFB.And the mRNA value of SARPlwas detected to increase significantly by RT-PCR and the protein expression was detected to increase significantly by Western blot (P＜0.05).The proliferation in the groups of the adenovirus infection and HSFB was positively regulated by SARP1 (P＜0.01) and the apoptosis of them was inhibited by the expression of SARP1 as compared to the control groups of HSFB and Ad-EGFP.It showed that the apoptosis index decreased as compared the group of infected fibroblasts to the control group by flow cytometry.Conclusions SARP1 could be highly expressed in HSFB by adenovirus infection,exhibiting the proliferation-enhancing and apoptosis-inhibiting effects on HSFB.

Polyamidoamine-polyethylene glycol (PAMAM-PEG) copolymers were synthesized using IPDI as coupling reagent by two-step method. The copolymers were characterized by IR spectrum and 1H NMR spectrum, and the PEG conjugating ratios of the copolymers were calculated equal to 10% and 30% separately. MTT assay indicated that after PEGylation a lower cytotoxicity of the copolymers could be found, and with increasing PEG conjugating ratio the cytotoxicity decreased obviously. Agarose gel retardation assay demonstrated that PAMAM-PEG copolymers could be combined with DNA and PAMAM-PEG/DNA complexes were prepared by self-assembly. DLS measurement showed that when N/P > or = 50, the particle size of copolymer/ gene complexes was in a range of 150-200 nm, and the zeta potential was in a range of 10-25 mV. In vitro gene transfection illustrated that when N/P < or = 50, the gene transfection efficiency of PAMAM-PEG copolymers was a little less than that of PAMAM-G5, but the transfection efficiency can be raised by increasing N/P ratio or transfection time. Considering both cytotoxicity and transfection efficiency aspects PAMAM-PEG-13 was more effect than PAMAM-PEG-39 in PEGylation.

Objective To investigate the prevalence rate of metabolic syndrome (MS) and its related diseases in Bengbu community residents. Methods 3246 residents aged from 25 to 74 years were chosen through cluster random sampling method, including 1459 males and 1787 females. MS and its related diseases were examined. Results (1) The prevalence rate and standardized rate of MS was 20. 5% and 16.0%, respectively, which reached higher level all over China. The prevalence rate of male and female was 22. 9% and 18. 6%, respectively. The highest prevalence rate occurred in presenium patients. (2)The prevalences of various metabolic diseases were increased with aging except for overweigh/obesity and MS (P<0.01). The prevalence of various metabolic diseases was 1 times higher in elderly patients than that in young patients, and the prevalence rate of MS in male and female increased to 2.8 times and 2.7 times, respectively. The prevalence rate of type 2 diabetes mellitus increased biggest, male to 7.9 times and female to 12.8 times compared with the original level. (3) The multiple components clustering rate of MS was high, only 33.8% of individuals had no metabolic disorder. Conclusions The prevalence rates of MS and its related diseases are high in Bengbu community residents. It is necessary to take comprehensive measures to prevent and control MS in community.

O-Carboxymethylchitosan (O-CMC) in 1000 g batch was prepared from chitin as starting material and its chemical structure was confirmed by analysis of IR and NMR. O-CMC solution, sodium hyaluronate (HA) solution and physiological saline were used in Sprague-Dawley rat model for prevention of postsurgical adhesions; after 7 days of an abdominal operation, the 3 groups were evaluated according to Belluco standard, the mean scores of O-CMC group, HA group and physiological saline group were 2.5 +/- 3.1, 3.3 +/- 3.6 and 10.3 +/- 1.0, respectively. Histological inspection showed that in O-CMC group, mesothelial cells on peritonaeum or cecum surfaces were almost restored; in HA group the injured surface of peritonaeum was mostly repaired, but in physiological saline group the injured surface of cecum was just a little repaired; there were extensive adhesions between peritonaeum and cecum, and inflammatory response was quite serious. Experimental results indicated that O-CMC and HA had excellent efficiency and O-CMC was slightly better than HA for the prevention of postsurgical adhesions.
Abdomen ; surgery ; Animals ; Chitosan ; analogs & derivatives ; therapeutic use ; Female ; Intestinal Diseases ; prevention & control ; Male ; Postoperative Complications ; prevention & control ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tissue Adhesions ; prevention & control

This study was designed to investigate the changes of prostaglandin I2 (PGI2) and nitric oxide (NO) secreted by endothelialized polyurethane small diameter artificial blood vessel. The peripheral blood mononuclear cells of healthy adult were separated and induced into endothelial progenitor cells (EPCs), which were identified by the methods of discrepancy microphage and fluorescent immunology labeling. After the induced cells being seeded on the polyurethane small-diameter artificial vessels, the endothelialized polyurethane small diameter artificial blood vessels were divided into four different experimental groups, including stationary group, low-flow shear stress group (5 dynes/cm2), medium-flow shearstress group (15 dynes/cm2), and high-flow shear stress group (25 dynes/cm2). Then, the levels of 6-ketoprostaglandin F1alpha (6-keto-PGF1alpha) and NO of different time were measured by enzyme-linked immunosorbent assay and nitrate reductase methods. The peripheral blood mononuclear cells differentiated into EPCs. They presented typical "spindie-shaped" appearance, and they were positively labeled by fluorescent acetylated-LDL, lectin, FLK-1 and vWF. Shear stress enhanced the production of NO and 6-keto-PGF1alpha by EPCs in a dose-dependent manner. Therefore, shear stress increases the secretion of NO and PGI2 by EPC, which suggests that shear stress can improve the antithrombogenic potentials of endothelialized polyurethane small diameter artificial blood vessel.
Bioartificial Organs ; Biocompatible Materials ; chemistry ; Blood Vessel Prosthesis ; Cell Adhesion ; Cell Differentiation ; Cells, Cultured ; Endothelial Cells ; cytology ; metabolism ; Epoprostenol ; metabolism ; Fibrinolytic Agents ; metabolism ; Humans ; In Vitro Techniques ; Leukocytes, Mononuclear ; cytology ; Nitric Oxide ; metabolism ; Polyurethanes ; chemistry ; Stress, Mechanical

In this study, the peripheral blood mononuclear cells of healthy adult were acquired and inducted by vascular endothelial growth factor, et cetera. The differentiated endothelial cells were observed and identified as EPCs by the double positive staining of fluorescent labeled acetylated-LDL and lectin, seeded on the polyurethane small-diameter artificial vessels, treated by shear stress of 15 dyn/cm2, and observed by scanning electronic microscopy. As a result, the peripheral blood mononuclear cells differentiated into EPCs. They were positively stained by labeled acetylated-LDL and lectin. Under observation of scanning electronic microscope, the unseeded polyurethane small-diameter artificial vessel being suited for the growth and spreading of the cells; the cell lineage on surface of artificial vessels of stationary group being arrayed in chaos, and that of shear stress group being arrayed in direction. Therefore, the peripheral cells can differentiate into EPCs, and EPCs can be used as novel source cells for the accelerated endothelialization of small diameter artificial vessel. Shear stress contributes to the mechanic moulding of cell lineage on the surface of artificial vessel.
Bioartificial Organs ; Biocompatible Materials ; Blood Vessel Prosthesis ; Cell Adhesion ; Cell Differentiation ; Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Leukocytes, Mononuclear ; cytology ; Polyurethanes ; chemistry ; Prosthesis Design ; Shear Strength ; Stem Cells ; cytology ; Stress, Mechanical