1.Role of exosome-derived miRNA-21-5p/Smad7 in quartz dust-induced pulmonary fibrosis in rats
Yang LU ; Xiaohui DING ; Tiantian WANG ; Mengtong XU ; Jiarui HAO ; Wenjing LI ; Jing SONG
Journal of Environmental and Occupational Medicine 2024;41(8):861-866
Background Quartz dust cannot be degraded in the lungs, and inhalation of a large amount of quartz dust in the occupational production process will lead to the occurrence of pulmonary fibrosis, and then develop into silicosis. In recent years, studies have found that exosomes may be involved in the pathogenesis of fibrotic diseases by carrying microribonucleic acid (miRNA), but the mechanism of their actions in silicosis still needs to be studied. Objective To investigate the role of exosome-derived miRNA-21-5p/mothers against decapentaplegic homolog 7 (Smad7) in quartz dust-induced pulmonary fibrosis in rats. Methods Twenty-four healthy male SD rats were randomly divided into four groups (six rats in each group): control 4-week group, control 16-week group, quartz 4-week group, and quartz 16-week group. At the beginning of the experiment, 1 mL of quartz suspension (50 mg·mL−1) and 1 mL of normal saline were injected into the trachea of rats in the quartz group and the control group, respectively, by means of one-time non-exposure intratracheal dust staining. Alveolar lavage was performed at the 4th and 16th weeks after dust staining, the exosomes in lavage solution were extracted by polyethylene glycol (PEG) precipitation, morphological identification was conducted by transmission electron microscopy (TEM), particle size of exosomes was detected by nano-tracking analysis (NTA), and the marker proteins CD9 and CD63 of exosomes were detected by Western blotting (WB). The expression of miRNA-21-5p in exosomes was determined by reverse transcription polymerase chain reaction (RT-PCR). The degree of lung tissue injury and fibrosis was observed by hematoxylin-eosin staining (HE) and Masson staining. The collagen content of lung tissue was detected by hydroxyproline (HYP) method. The expression of Smad7 protein in lung tissue was detected by WB. Results The results of pathological staining showed that compared with the control group, lung inflammatory cell infiltration, alveolar wall thickening, and collagen increase were observed after 4 weeks of dusting, and collagen deposition and silicon nodules appeared after 16 weeks of dusting. Compared with the control group, the expression level of HYP in the lung tissue of the quartz group was increased after 4 weeks and 16 weeks of dust staining (P<0.05). Transmission electron microscopy showed that exosomes were saucer-shaped, and the average particle size of exosomes was 95.8 nm by NTA. Positive expression of exosome marker proteins CD9 and CD81 was found by WB. Compared with the control group, the expression of exosome-derived miRNA-21-5p in alveolar lavage fluid in the quartz group increased in the 4th week and the 16th week (P<0.05), and the expression of Smad7 protein in lung tissue decreased (P<0.05). Conclusion Exosome-derived miRNA-21-5p and Smad7 may be involved in the mechanism of quartz dust-induced pulmonary fibrosis in rats.
2.Analysis of N6-methyladenosine methylation and N6-methyladenosine RNA binding protein 1 in rats with subchronic aluminum exposure
DING Xiaohui ; LU Yang ; HAO Jiarui ; WANG Tiantian ; XU Mengtong ; SONG Jing
Journal of Preventive Medicine 2024;36(9):825-828
Objective:
To explore the effects of subchronic aluminum exposure on the level of N6-methyladenosine (m6A) methylation and the expression of N6-methyladenosine RNA binding protein 1 (YTHDF1) in the hippocampus of rats.
Methods:
Twenty-four healthy male SD rats were randomly divided into the control group (normal saline), the low dose group [10 μmol/kg Al(mal)3], the medium dose group [20 μmol/kg Al(mal)3] and the high dose group [40 μmol/kg Al(mal)3], with 6 rats in each group. The Al(mal)3 solution was administered via intraperitoneal injection on alternate days for 90 days. Escape latency, target quadrant dwell time and platform crossing times were tested to evaluate the learning and memory ability of the rats by the Morris water maze test after exposure. The brain tissue was weighted and the brain-to-body weight ratio was calculated after euthanasia. The level of m6A methylation and the expression of YTHDF1 were determined by enzyme-linked immunosorbent assay and western blot assay, respectively.
Results:
All rats survived during aluminum exposure period. The brain-to-body weight ratios of the control group and the low, medium and high dose groups were (0.46±0.06)%, (0.44±0.04)%, (0.49±0.06)% and (0.51±0.07)%, respectively, with no statistically significant differences (P>0.05). The escape latency of rats in the high dose group was longer than that in control and low group during the third to fifth day (both P>0.05). The escape latency of rats in all groups was shortened with the increase of training days (P<0.05). The target quadrant dwell time of rats in low, medium and high dose groups were lower than that in control group, and the platform crossing times of rats in high dose group were lower than that in control group (all P<0.05). The methylation level of m6A and expression level of YTHDF1 in hippocampus of rats in medium and high dose groups was higher than that in control group (both P<0.05).
Conclusion
The learning and memory impairment caused by subchronic aluminum exposure may be related to the increase of m6A methylation level and the decrease of YTHDF1 expression.
3.METTL3 regulates glucose transporter expression in placenta exposed to hyperglycemia through the mTOR signaling pathway
Jie NING ; Jing HUAI ; Shuxian WANG ; Jie YAN ; Rina SU ; Muqiu ZHANG ; Mengtong LIU ; Huixia YANG
Chinese Medical Journal 2024;137(13):1563-1575
Background::Alterations in the placental expression of glucose transporters (GLUTs), the crucial maternal-fetal nutrient transporters, have been found in women with hyperglycemia in pregnancy (HIP). However, there is still uncertainty about the underlying effect of the high-glucose environment on placental GLUTs expression in HIP.Methods::We quantitatively evaluated the activity of mammalian target of rapamycin (mTOR) and expression of GLUTs (GLUT1, GLUT3, and GLUT4) in the placenta of women with normal pregnancies (CTRL, n = 12) and pregnant women complicated with poorly controlled type 2 diabetes mellitus (T2DM, n = 12) by immunohistochemistry. In addition, BeWo cells were treated with different glucose concentrations to verify the regulation of hyperglycemia. Then, changes in the expression of GLUTs following the activation or suppression of the mTOR pathway were also assessed using MHY1485/rapamycin (RAPA) treatment or small interfering RNA (siRNA)-mediated silencing approaches. Moreover, we further explored the alteration and potential upstream regulatory role of methyltransferase-like 3 (METTL3) when exposed to hyperglycemia. Results::mTOR, phosphorylated mTOR (p-mTOR), and GLUT1 protein levels were upregulated in the placenta of women with T2DM compared with those CTRL. In BeWo cells, mTOR activity increased with increasing glucose concentration, and the expression of GLUT1, GLUT3, and GLUT4 as well as GLUT1 cell membrane translocation were upregulated by hyperglycemia to varying degrees. Both the drug-mediated and genetic depletion of mTOR signaling in BeWo cells suppressed GLUTs expression, whereas MHY1485-induced mTOR activation upregulated GLUTs expression. Additionally, high glucose levels upregulated METTL3 expression and nuclear translocation, and decreasing METTL3 levels suppressed GLUTs expression and mTOR activity and vice versa. Furthermore, in METTL3 knockdown BeWo cells, the inhibitory effect on GLUTs expression was eliminated by activating the mTOR signaling pathway using MHY1485. Conclusion::High-glucose environment-induced upregulation of METTL3 in trophoblasts regulates the expression of GLUTs through mTOR signaling, contributing to disordered nutrient transport in women with HIP.
4.Clinical significance of IL-18 and IL-18-binding protein in bone marrow of patients with myelodysplastic syndrome
Ting WANG ; Ningyuan RAN ; Qiulin CHEN ; Donglan LIU ; Mengtong ZANG ; Nianbin LI ; Xin HE ; Jing GUAN ; Rong FU ; Zonghong SHAO
Chinese Journal of Hematology 2024;45(3):284-289
Objective:To analyze the level and clinical significance of IL-18 and IL-18-binding protein (BP) in the bone marrow of patients with myelodysplastic syndrome (MDS) .Methods:A total of 43 newly diagnosed patients with MDS who were admitted to the Department of Hematology, Tianjin Medical University General Hospital, from July 2020 to February 2021 were randomly selected. The control group consisted of 14 patients with acute myeloid leukemia (AML) and 25 patients with iron-deficiency anemia (IDA). The levels of IL-18 and IL-18 BP in the bone marrow supernatant were measured, and their correlations with MDS severity, as well as the functionality of CD8 + T cells and natural killer cells, was analyzed. Results:The levels of IL-18, IL-18 BP, and free IL-18 (fIL-18) in the bone marrow supernatant of patients with MDS were higher than in the IDA group. The level of fIL-18 was linearly and negatively correlated with the MDS-International Prognostic Scoring System (IPSS) score. IL-18 receptor (IL-18Rα) expression on CD8 + T cells in the MDS group was lower than in the IDA group, and the levels of fIL-18 and IL-18Rα were positively correlated with CD8 + T-cell function in the MDS group. Conclusion:IL-18 BP antagonizes IL-18, leading to a decrease in fIL-18 in the bone marrow microenvironment of patients with MDS, affecting CD8 + T-cell function, which is closely related to MDS severity; therefore, it may become a new target for MDS treatment.
5.Effects of aluminum on expressions of fat mass and obesity-associated protein and brain-derived neurotrophic factor in rat brain and PC12 cells
Mengtong XU ; Tiantian WANG ; Wenjing LI ; Chunman YUAN ; Jing SONG
Journal of Environmental and Occupational Medicine 2022;39(8):908-912
Background Chemical modification of RNA is a recent hotspot in the field of epigenetics, but the specific mechanism of chemical modification of RNA in aluminum neurotoxicity has not been fully reported. Objective To investigate the alterations of fat mass and obesity-associated protein (FTO), that demethylates N6-methyladenosine (m6A), and brain-derived neurotrophic factor (BDNF) in different brain regions of rats and rat adrenal pheochromocytoma differentiated cells (PC12 cells) following aluminum exposure. Methods Animal experiment: Twenty-four healthy male SD rats were randomly divided into a control group (normal saline) and 10, 20, and 40 μmol·kg−1 exposure groups according to body weight, with 6 rats in each group. Maltol aluminum [Al(mal)3] was injected intraperitoneally every other day for 3 months. Cell experiment: PC12 cells were divided into a control group and 100, 200, and 400 μmol·L−1 exposure groups exposed to Al(mal)3 for 24 h. After exposure, the learning and memory ability of rats was measured by water maze experiment, and the protein expression levels of FTO and BDNF in rat cortex (n=6) and hippocampus (n=6) samples as well as in PC12 cells (n=5) were determined by Western blotting. Results The results of water maze test showed that the escape latency of the 40 μmol·kg−1Al(mal)3 group was higher than those of the control group, the 10 μmol·kg−1Al(mal)3 group, and the 20 μmol·kg−1Al(mal)3 group on day 3, 4, and 5 of training (P<0.05). The retention time of the target quadrant of the 40 μmol·kg−1Al(mal)3 group was also reduced compared with that of the control group (P<0.05), indicating that aluminum exposure damaged the learning and memory ability of the rats. The Western blotting results showed that in the cortex, compared with the control group, the protein expression levels of FTO and BDNF in the aluminum treated groups were decreased (P<0.05). In the hippocampus, compared with the control group, the protein expression levels of FTO and BDNF in the 20 μmol·kg−1 and the 40 μmol·kg−1Al(mal)3 groups were decreased (P<0.05). In PC12 cells, compared with the control group, the protein expression levels of FTO and BDNF in the aluminum treated groups were decreased (P<0.05). Conclusion Aluminum-induced learning and memory impairment is related to a simultaneous reduction of FTO and BDNF protein expressions, suggesting that m6A methylation may be involved.
6.Clinicopathological features of metastatic melanoma in effusion cytology of serosal cavity
Qin XIA ; Xiaona CHANG ; Bo HUANG ; Xuefei LI ; Danju LUO ; Qingjie WANG ; Mengtong JIANG ; Jun FAN ; Diwei ZHOU
Chinese Journal of Pathology 2024;53(8):837-842
Objective:To investigate the clinical, cytomorphology, immunocytochemical and molecular features of metastatic melanoma in serosal cavity effusion.Methods:Cytological specimens of 14 patients with melanoma in the chest and abdomen were collected from 2017 to 2023, at the Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. SOX10, S-100 protein, PRAME, BRAF V600E, HMB45, and Melan A were detected by immunocytochemical methods. Fourteen cases were tested for routine antibody combinations, including Claudin4, HEG1, Calretinin, CD68, etc. Four of the patients had biopsy or surgical samples of metastatic solid lesions of primary sites, and further next-generation sequencing (NGS) or amplification refractory mutation system (ARMS)-PCR molecular test was performed. In addition, 30 cases of serosal effusion samples were collected as control groups (10 cases of benign mesothelial cell reactive hyperplasia, 10 cases of mesothelioma, and 10 cases of metastatic lung adenocarcinoma).Results:Among the 14 cases of melanoma, there were 7 males and 7 females, with ages ranging from 35 to 86 years, and an average age of 57 years, there 10 cases aged ≥50 years. The tumor cells in the serosal effusion varied in morphology and degree of atypia. SOX10 was positive in all 14 cases (14/14), S-100 protein was positive in 10 cases (10/14), PRAME was positive in 12 cases (12/14), BRAF V600E was positive in 10 cases (10/14), HMB45 was positive in 12 cases (12/14), and Melan A was positive in 13 cases (13/14). In 4 patients with histological correlation, the cytological and histological expression of SOX10, BRAF V600E, and PRAME was positive in all 4 cases (4/4); S-100 protein was positive in 2 cases (2/4); and HMB45 and Melan A were positive in 3 cases (3/4). Using NGS or ARMS-PCR, missense mutations of BRAF V600E were detected in all 4 patients; TERT promoter mutations was detected in 1 case; and CDKN2A terminating mutations and MSI1 deletion mutations were detected in the other case. SOX10, S-100, HMB45, Melan A, PRAME and BRAF V600E were all negative in 30 control samples of serosal cavity effusion.Conclusion:By observing the morphology of tumor cells, immunocytochemical test of several combination markers, especially the expression of SOX10, BRAF V600E and PRAME, can help to improve the positive diagnosis rate of melanoma in serous cavity effusion.
7.The application of Xing's ureteroileal anastomosis technique in urinary diversion
Boda GUO ; Dong CHEN ; Feiya YANG ; Mingshuai WANG ; Yajian LI ; Qinxin ZHAO ; Wenkuan WANG ; Liyuan WU ; Sai LIU ; Mengtong WANG ; Sujun HAN ; Nianzeng XING
Chinese Journal of Urology 2023;44(3):187-190
Objective:To evaluate the clinical value of Xing's ureteroileal anastomosis technique in radical cystectomy.Methods:The data of 38 patients who underwent radical cystectomy with Xing's ureteroileal anastomosis technique at Cancer Hospital, Chinese Academy of Medical Sciences and Beijing Chaoyang Hospital from July 2013 to June 2021 were retrospectively reviewed. There were 30 males and 8 females. The mean age was 61.6±15.1 years old. The mean body mass index (BMI) was 25.1±2.7 kg/m 2. The American Society of Anesthesiology (ASA) graded 25 cases as grade 1, 10 cases as grade 2 and 3 cases as grade 3. There were 35 cases with stage cT 2N 0M 0 and 3 cases with cT 3N 0M 0. All patients underwent radical cystectomy and ileal conduit, and the ureteroileal anastomosis was performed using the Xing's ureteroileal anastomosis technique. Afferent loop entry was divided equally into two lumens. After 1.5 cm-long lengthwise incisions, each ureter was directly and end-to-end anastomosed to the aforementioned lumens. Postoperative information was recorded, including ureteric stricture, ureteric reflux, hydronephrosis, anastomotic leakage, renal calculus, urinary tract infection, and pyelonephritis. Results:Ureteroileal anastomosis was performed successfully in 38 cases with 76 units. The median follow-up time was 35.6 (17.0, 46.3) months. Three patients developed unilateral anastomotic stenosis after operation. Five patients had unilateral ureteral reflux. Two patients had unilateral hydronephrosis. No anastomotic leakage, urinary tract infection, or pyelonephritis occurred after the operation. Renal calculus appeared in 3 cases, all on the left unit.Conclusions:Xing's ureteroileal anastomosis technique is a simple method with few postoperative and good functional outcomes.
8.Preparation and catalytic properties of catalase-inorganic hybrid nanoflowers.
Jiao PANG ; Mengtong JIANG ; Yuxin LIU ; Mingyu LI ; Jiaming SUN ; Conggang WANG ; Xianzhen LI
Chinese Journal of Biotechnology 2022;38(12):4705-4718
Catalase is widely used in the food, medical, and textile industries. It possesses exceptional properties including high catalytic efficiency, high specificity, and environmental friendliness. Free catalase cannot be recycled and reused in industry, resulting in a costly industrial biotransformation process if catalase is used as a core ingredient. Developing a simple, mild, cost-effective, and environmentally friendly approach to immobilize catalase is anticipated to improve its utilization efficiency and enzymatic performance. In this study, the catalase KatA derived from Bacillus subtilis 168 was expressed in Escherichia coli. Following separation and purification, the purified enzyme was prepared as an immobilized enzyme in the form of enzyme-inorganic hybrid nanoflowers, and the enzymatic properties were investigated. The results indicated that the purified KatA was obtained through a three-step procedure that included ethanol precipitation, DEAE anion exchange chromatography, and hydrophobic chromatography. Then, by optimizing the process parameters, a novel KatA/Ca3(PO4)2 hybrid nanoflower was developed. The optimum reaction temperature of the free KatA was determined to be 35 ℃, the optimum reaction temperature of KatA/Ca3(PO4)2 hybrid nanoflowers was 30-35 ℃, and the optimum reaction pH of both was 11.0. The free KatA and KatA/Ca3(PO4)2 hybrid nanoflowers exhibited excellent stability at pH 4.0-11.0 and 25-50 ℃. The KatA/Ca3(PO4)2 hybrid nanoflowers demonstrated increased storage stability than that of the free KatA, maintaining 82% of the original enzymatic activity after 14 d of storage at 4 ℃, whereas the free KatA has only 50% of the original enzymatic activity. In addition, after 5 catalytic reactions, the nanoflower still maintained 55% of its initial enzymatic activity, indicating that it has good operational stability. The Km of the free KatA to the substrate hydrogen peroxide was (8.80±0.42) mmol/L, and the kcat/Km was (13 151.53± 299.19) L/(mmol·s). The Km of the KatA/Ca3(PO4)2 hybrid nanoflowers was (32.75±2.96) mmol/L, and the kcat/Km was (4 550.67±107.51) L/(mmol·s). Compared to the free KatA, the affinity of KatA/Ca3(PO4)2 hybrid nanoflowers to the substrate hydrogen peroxide was decreased, and the catalytic efficiency was also decreased. In summary, this study developed KatA/Ca3(PO4)2 hybrid nanoflowers using Ca2+ as a self-assembly inducer, which enhanced the enzymatic properties and will facilitate the environmentally friendly preparation and widespread application of immobilized catalase.
Catalase
;
Nanostructures/chemistry*
;
Hydrogen Peroxide/metabolism*
;
Enzymes, Immobilized/chemistry*
;
Catalysis
9.Oral squamous cell carcinomas: state of the field and emerging directions.
Yunhan TAN ; Zhihan WANG ; Mengtong XU ; Bowen LI ; Zhao HUANG ; Siyuan QIN ; Edouard C NICE ; Jing TANG ; Canhua HUANG
International Journal of Oral Science 2023;15(1):44-44
Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% of oral malignancies and impairs appearance, pronunciation, swallowing, and flavor perception. In 2020, 377,713 OSCC cases were reported globally. According to the Global Cancer Observatory (GCO), the incidence of OSCC will rise by approximately 40% by 2040, accompanied by a growth in mortality. Persistent exposure to various risk factors, including tobacco, alcohol, betel quid (BQ), and human papillomavirus (HPV), will lead to the development of oral potentially malignant disorders (OPMDs), which are oral mucosal lesions with an increased risk of developing into OSCC. Complex and multifactorial, the oncogenesis process involves genetic alteration, epigenetic modification, and a dysregulated tumor microenvironment. Although various therapeutic interventions, such as chemotherapy, radiation, immunotherapy, and nanomedicine, have been proposed to prevent or treat OSCC and OPMDs, understanding the mechanism of malignancies will facilitate the identification of therapeutic and prognostic factors, thereby improving the efficacy of treatment for OSCC patients. This review summarizes the mechanisms involved in OSCC. Moreover, the current therapeutic interventions and prognostic methods for OSCC and OPMDs are discussed to facilitate comprehension and provide several prospective outlooks for the fields.
Humans
;
Carcinoma, Squamous Cell/therapy*
;
Squamous Cell Carcinoma of Head and Neck
;
Mouth Neoplasms/therapy*
;
Head and Neck Neoplasms
;
Tumor Microenvironment