OBJECTIVETo explore the influences of di-(2-ethylhexyl)phthalate (DEHP) and its principle metabolite mono(2-ethylhexyl)phthalate (MEHP) on spermatogenic cell apoptosis in young male Wistar rats.

METHODSNinety-eight 2-week-old male Wistar rats were randomly divided into 14 equal groups to receive daily intragastric administration of 0.2 ml/kg normal saline for 3 weeks (normal control), 100 mg/kg cyclophosphamide (CTX) for 1 week (positive control), 100, 200, and 300 mg/kg DEHP or MEHP for 1 week, or 100 mg/kg DEHP or MEHP for 1, 2, and 3 weeks. After the treatments, the pathological changes of the testicular tissues were examined, spermatogenic cell apoptosis was detected, and serum sex hormones levels were measured using TUNEL assay or radioimmunoassays.

RESULTSCTX, DEHP, and MEHP all caused shrinkage, development retardation and quantitative reduction of spermatogenic cells with and mitochondrial swelling vacuolar changes. The damage of spermatogenic cells increased significantly with the increment of DEHP and MEHP doses and exposure time. Both DEHP and MEHP treatments resulted in significantly increased cell apoptosis index (AI) in close correlation with the exposure doses and duration (P<0.01). DEHP and MEHP treatments also significantly increased serum levels of follicle stimulating hormone and luteinizing hormone and decreased testosterone levels in a dose- and time-dependent manner (P<0.05).

CONCLUSIONDEHP and MEHP can induce obvious apoptosis of spermatogenic cells in young male rats with a dose- and time-dependent effect.

Animals ; Apoptosis ; drug effects ; Diethylhexyl Phthalate ; analogs & derivatives ; toxicity ; Dose-Response Relationship, Drug ; Environmental Exposure ; Male ; Rats ; Rats, Wistar ; Spermatozoa ; cytology ; drug effects

OBJECTIVETo investigate RANK-RANKL expression in the kidneys of a rat model of puromycin aminonucleoside nephropathy (PAN).

METHODSThirty-six SD rats were randomly divided into PAN model group and normal control group. PAN was induced by a single intravenous injection of 100 mg/kg puromycin aminonucleoside. Serum creatinine and 24-hour urinary protein were measured on days 3, 7, and 14 after the injection, and renal pathologies were assessed with optical and immune transmission electron microscopy. The expression of RANK and RANKL in the kidneys was examined using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting.

RESULTSThe PAN model rats showed massive proteinuria and elevated serum creatinine on day 3, which peaked on day 7. RANK-RANKL protein and mRNA expressions in PAN model group was higher than those in the control group. In the PAN rats, RANK was expressed mainly on the top cell membrane and in the cytoplasm of renal podocytes with a significantly increased expression level compared with that in the control group.

CONCLUSIONThe PAN rat model shows aberrant RANK and RANKL expressions in the podocytes, indicating their contribution to podocyte injury in PAN.

Animals ; Creatinine ; blood ; Female ; Kidney ; drug effects ; metabolism ; Kidney Diseases ; chemically induced ; metabolism ; pathology ; Male ; Podocytes ; drug effects ; metabolism ; Proteinuria ; pathology ; Puromycin Aminonucleoside ; adverse effects ; RANK Ligand ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor Activator of Nuclear Factor-kappa B ; metabolism

Objective To investigate the effects of fluoride on protein oxidative damage in rat plasma by measuring oxidative stress levels,advanced glycation end products (AGEs) and advanced oxidation protein products (AOPP).Methods Eighty SPF male 3-week-old Wistar rats weighing (82.34 ± 10.60) g were randomly divided into 4 groups,20 rats in each group.The control group drank distilled water,and the fluoride groups drank distilled water with fluoride concentrations of 25,50 and 100 mg/L,respectively.Rats were allowed to eat and drink freely,and they were sacrificed at 1 month and 3 month,respectively,and samples such as urine,femur and peripheral blood were collected for experiments.Fluoride contents in urine and bone were detected by ion selective electrode method,the superoxide dismutase (SOD) activity was detected by hydroxylamine method,malondialdehyde (MDA) content was detected by thiobarbituric acid (TBA) method,and AGEs and AOPP contents were detected by enzyme linked immunosorbent assay (ELISA).Results For 1 month and 3 months,compared urinary fluoride contents (mg/L:2.088 + 0.638,9.170 ± 2.865,20.094 ± 8.186,54.866 ± 2.866;2.202 ± 1.282,9.112 ± 2.364,21.854 ±8.325,52.513 ± 16.211),and bone fluoride contents (mg/kg:324.985 ± 127.094,846.148 ± 331.861,1 886.601 ±250.140,2 420.971 ± 135.883;417.591 ± 88.324,1 582.243 ± 347.975,2 163.519 ± 614.932,2 755.434 ±265.370) in control group and fluoride concentrations of 25,50 and 100 mg/L groups,the differences were statistically significant (F =88.379,29.225;87.440,33.998,P ＜ 0.05).For 1 month and 3 months,compared SOD activity (U/ml:32.469 ± 5.674,35.931 ± 2.262,36.746 ± 3.994,38.042 ± 4.632;31.027 ± 4.147,30.777 ±4.791,34.148 ± 1.755,36.585 ± 2.860) and AGEs contents (μg/L:26.977 ± 5.285,33.303 ± 6.226,28.021 ±5.946,34.117 ± 6.706;35.681 ± 3.802,33.651 ± 7.214,28.114 ± 4.660,24.330 ± 3.581) in control group and fluoride concentrations of 25,50 and 100 mg/L groups,the differences were statistically significant (F =2.896,5.780;3.565,10.195,P ＜ 0.05).By factorial design anova,there was an interaction between the exposure concentration and exposure time of fluorine and the content of AGEs (F =8.957,P ＜ 0.01).Conclusion Excessive fluoride can affect urinary,bone fluoride contents,SOD activity,AGEs content,suggesting that excessive fluoride may regulate protein expression through direct and indirect oxidative damage pathways,which leading to fluorosis.

Objective To investigate the effects of fluoride exposure dose and exposure time on the expression of 5-methylcytosine (5-mC) in blood,liver,kidney and brain of rats;and to understand whether there is a difference in the effects of fluoride on DNA methylation levels in different tissues.Methods Eighty three-week old SPF male Wistar rats were randomly divided into four groups according to body weight [(82.34 ± 10.60) g],with 20 rats in each group.The rats of control group drank distilled water and the fluoride group's drank distilled water containing 25,50 and 100 mg/L of F ion,respectively.Rats were sacrificed after fed for 1 month and 3 months (n =10),and peripheral blood and tissue samples were collected.The incidence of dental fluorosis was observed in rats.Bone and urine fluoride content was detected by ion selective electrode method.The content of 5-mC in blood,liver,kidney and brain was detected by enzyme-linked immunosorbent assay (ELISA).The independent and interactive effects of fluoride exposure dose and exposure time on 5-mC in rat peripheral blood and different tissues were analyzed by factorial design anova.Results After feeding for 1 month and 3 months,all rats in the fluoride group had dental fluorosis with different severities,while none dental fluorosis was found in the control groups.Fluoride exposure dose and exposure time had a main effect on bone fluoride contents [1 month:(324.985 + 127.094),(846.148 ± 331.861),(1 886.601 + 250.140),(2 420.971 + 135.883) mg/kg;3 months:(417.591 ± 88.324),(1 582.243 ± 347.975),(2 163.519 ± 614.932),(2 755.434 ± 265.370)mg/kg;F =96.692,13.077,P ＜ 0.01],respectively,but there was no interaction effect (F =2.013,P ＞ 0.05);fluoride exposure dose had a main effect on urinary fluoride contents (F =62.358,P ＜ 0.01),the exposure time had no effect on it (F =0.862,P ＞ 0.05),and there was no interaction effect (F =0.081,P ＞ 0.05).Fluoride exposure dose had a main effect on the 5-mC content in the blood (F =8.446,P ＜ 0.01),the exposure time had no effect on it (F =0.095,P ＞0.05),and there had an interaction effect (F =4.676,P ＜ 0.01).Fluoride exposure dose and exposure time had a main effect on the 5-mC content in the liver,respectively (F =4.737,7.064,P ＜ 0.01 or ＜ 0.05),and an interaction effect was exist (F =8.302,P ＜ 0.01).Fluoride exposure time had a main effect on the 5-mC content in the kidney (F =6.340,P ＜ 0.05),the exposure dose had no effect on it (F =0.140,P ＞ 0.05),and there was no interaction effect (F =1.269,P ＞ 0.05).Fluoride exposure dose and exposure time had no effect on 5-mC content in the brain (F =0.633,2.065,P ＞ 0.05).Conclusion Fluoride exposure dose and exposure time have the different effect on the levels of 5-mC in blood,liver,kidney and brain,suggesting that there may be differences in the effects of fluoride on DNA methylation levels in different tissues.

BACKGROUND: T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domains (TIGIT), an inhibitory receptor expressed on T cells, plays a dysfunctional role in antiviral infection and antitumor activity. However, it is unknown whether TIGIT expression on T cells influences the immunological effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inactivated vaccines. METHODS: Forty-five people living with HIV (PLWH) on antiretroviral therapy (ART) for more than two years and 31 healthy controls (HCs), all received a third dose of a SARS-CoV-2 inactivated vaccine, were enrolled in this study. The amounts, activation, proportion of cell subsets, and magnitude of the SARS-CoV-2-specific immune response of TIGIT + CD4 + and TIGIT + CD8 + T cells were investigated before the third dose but 6 months after the second vaccine dose (0W), 4 weeks (4W) and 12 weeks (12W) after the third dose. RESULTS: Compared to that in HCs, the frequency of TIGIT + CD8 + T cells in the peripheral blood of PLWH increased at 12W after the third dose of the inactivated vaccine, and the immune activation of TIGIT + CD8 + T cells also increased. A decrease in the ratio of both T naïve (T N ) and central memory (T CM ) cells among TIGIT + CD8 + T cells and an increase in the ratio of the effector memory (T EM ) subpopulation were observed at 12W in PLWH. Interestingly, particularly at 12W, a higher proportion of TIGIT + CD8 + T cells expressing CD137 and CD69 simultaneously was observed in HCs than in PLWH based on the activation-induced marker assay. Compared with 0W, SARS-CoV-2-specific TIGIT + CD8 + T-cell responses in PLWH were not enhanced at 12W but were enhanced in HCs. Additionally, at all time points, the SARS-CoV-2-specific responses of TIGIT + CD8 + T cells in PLWH were significantly weaker than those of TIGIT - CD8 + T cells. However, in HCs, the difference in the SARS-CoV-2-specific responses induced between TIGIT + CD8 + T cells and TIGIT - CD8 + T cells was insignificant at 4W and 12W, except at 0W. CONCLUSIONS TIGIT expression on CD8 + T cells may hinder the T-cell immune response to a booster dose of an inactivated SARS-CoV-2 vaccine, suggesting weakened resistance to SARS-CoV-2 infection, especially in PLWH. Furthermore, TIGIT may be used as a potential target to increase the production of SARS-CoV-2-specific CD8 + T cells, thereby enhancing the effectiveness of vaccination.
Humans ; Antibodies, Viral ; CD8-Positive T-Lymphocytes ; COVID-19/complications* ; COVID-19 Vaccines/immunology* ; HIV Infections/complications* ; Receptors, Immunologic ; SARS-CoV-2