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1.
Aquat Toxicol ; 273: 107008, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941808

RESUMO

Environmental estrogens (EEs) are found extensively in natural waters and negatively affect fish reproduction. Research on the reproductive toxicity of EEs mixtures in fish at environmentally relevant concentrations is scarce. In this study, adult male zebrafish were exposed for 60 days to EES (a mixture of EEs), EE2-low (5.55 ng/L, with an estrogenic potency equal to EES), and EE2-high (11.1 ng/L). After exposure, the expression levels of vtg1, vtg3, and esr1 in the livers in EES-treated fish remained unaltered, whereas they were significantly increased in EE2-treated fish. Both EE2-high and EES exposures notably reduced the gonad somatic index and sperm count. A disrupted spermatogenesis was also observed in the testes of EE2-high- and EES-exposed fish, along with an alteration in the expression of genes associated with spermatogonial proliferation (pcna, nanog), cell cycle transition (cyclinb1, cyclind1), and meiosis (aldh1a2, cyp26a1, sycp3). Both EE2 and EES significantly lowered plasma 11-ketotestosterone levels in males, likely by inhibiting the expression level of genes for its synthesis (scc, cyp17a1 and cyp11b2), and increased 17ß-estradiol (E2) levels, possibly through upregulating the expression of cyp19a1a. A significant increase in tnfrsf1a expression and the tnfrsf1a/tnfrsf1b ratio in EE2-high and EES-treated males also suggests increased apoptosis via the extrinsic pathway. Further investigation showed that both EE2-high and EES diminished the sexual behavior of male fish, accompanied with reduced E2 levels in the brain and the expression of genes in the kisspeptin/gonadotropin-releasing hormone system. Interestingly, the sexual behavior of unexposed females paired with treated males was also reduced, indicating a synergistic effect. This study suggests that EES have a more severe impact on reproduction than EE2-low, and EEs could interfere not only with spermatogenesis in fish, but also with the sexual behaviors of both exposed males and their female partners, thereby leading to a more significant disruption in fish reproduction.


Assuntos
Estrogênios , Espermatogênese , Poluentes Químicos da Água , Peixe-Zebra , Animais , Masculino , Peixe-Zebra/fisiologia , Espermatogênese/efeitos dos fármacos , Feminino , Poluentes Químicos da Água/toxicidade , Estrogênios/toxicidade , Comportamento Sexual Animal/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/sangue , Testosterona/análogos & derivados
2.
Am J Transl Res ; 14(9): 6726-6736, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247269

RESUMO

To retrospectively compare the clinical efficacy and safety of CT-guided percutaneous injection of lobaplatin vs. ethanol for chemical ablation combined with radiofrequency ablation (RFA) in patients with hepatocellular carcinomas (HCCs) in high-risk locations. From January 2017 to June 2018, a total of 41 patients with HCCs in high-risk locations were enrolled and divided into two groups: percutaneous lobaplatin injection (PLI+RFA) group and percutaneous ethanol injection (PEI+RFA) group. The mixture of lobaplatin or ethanol was accurately injected into the high-risk part of the tumors, while RFA ablated the non-high-risk part. The efficacy and safety were compared between the two groups. 41 patients had 51 lesions in high-risk locations, including 24 cases with 30 lesions in PLI+RFA group and 17 cases with 21 lesions in PEI+RFA group. The complete ablation rate was 93.3% (28/30) in PLI+RFA group and 90.5% (19/21) in PEI+RFA group (P=1.000). The 2-year local tumor progression rate of PLI+RFA group and PEI+RFA group was 20.0% (6/30) and 19.0% (4/21), respectively (P=1.000). No significant differences were found in time to progression and overall survival between the two groups (P=0.501 and P=0.424, respectively). The incidence and severity of adverse events between the two groups were similar (P > 0.05). No severe complications were observed in both groups. Percutaneous lobaplatin injection combined with RFA in the treatment of HCC in high-risk locations may achieve the complete ablation rate similar to percutaneous ethanol injection combined with RFA, but further research is needed to confirm.

3.
J Phys Chem B ; 124(44): 9803-9811, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33100008

RESUMO

The multidrug resistance protein MRP1 is an ATP binding cassette (ABC) transporter that confers resistance to many anticancer drugs and regulates redox homeostasis, inflammation, and hormone secretion. MRP1 actively transports compounds across cell membranes, and the presence of glutathione (GSH) is required in many cases. However, the process of MRP1-mediated substrate transportation has been poorly understood. With extensive molecular dynamics simulations, we have found a sandwich-like structure which is generated by GSH, a transmembrane α-helices 11 (TM11)-TM17 axis, and anticancer drugs. This structure is crucial in MRP1 transportation. It triggers the motion of TM11 and TM17, followed by the movement of nucleotide-binding domains 1 (NBD1) and 2 (NBD2), and finally an occluded structure is formed. Trp1246, Lys332, and Phe594 were identified as the main contributors in the formation of the sandwich-like structure. Our findings clearly explain the synergy of GSH with an anticancer drug in MRP1 transportation and have significant meanings for the rational design of novel inhibitors against MRP1.


Assuntos
Antineoplásicos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Transporte Biológico , Glutationa/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(4): 485-490, 2020 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895100

RESUMO

Objective To explore the molecular mechanism of human papillomavirus subtype 16(HPV-16)E7 oncogene-induced DNA re-replication in response to DNA damage. Methods Flow cytometry was performed to examine the cell cycle changes in RPE1 E7 cells stably expressing HPV-16 E7 and its control cell RPE1 Vector after DNA damage.Immunoblotting assay was used to evaluate the early mitotic inhibitor 1(Emi1)expression in RPE1 E7 and RPE1 Vector cells with or without DNA damage.The changes of the proportion of polyploidy was detected by flow cytometry in DNA-damaged RPE1 E7 cells interfered by Emi1 small interfering RNA. Results Compared with the control cells,the proportion of polyploids in RPE1 E7 cells was significantly increased in response to DNA damage(t=6.397,P=0.0031).Emi1 protein expression was significantly increased in DNA damaged RPE1 E7 cells(t=8.241,P=0.0012).The polyploid ratio of RPE1 E7 cells was significantly reduced after Emi1 was interfered by two independent small interfering RNAs(t=2.916,P=0.0434;t=3.452,P=0.0260). Conclusion In response to DNA damage,Emi1 promoted DNA re-replication caused by HPV-16 E7.


Assuntos
Replicação do DNA , Dano ao DNA , Papillomavirus Humano 16 , Mitose , Proteínas Oncogênicas Virais
5.
Aquat Toxicol ; 224: 105503, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32438217

RESUMO

Tributyltin (TBT) was reported to affect sexual behavior and gametogenesis in fish. However, the modes of action involved are largely unclear. In order to elucidate the toxicological mechanisms of TBT in reproduction, zebrafish (Danio rerio) males were exposed to TBT at concentrations of 100 and 500 ng/L for 28 days. After exposure, the sperm count of the treated fish was sharply decreased though the testis weight and gonadosomatic index remained unchanged. Moreover, reduced number of spermatogonia and spermatozoa and increased spermatocytes were observed in TBT-treated fish by histological observation and PCNA-immunostaining. Increased number of apoptotic-positive spermatocytes was also present in TBT-treated fish, indicating an enhanced apoptosis in these cells. Consistent to decreased number of spermatogonia, down-regulated expressions of genes responsible for germ cell proliferation (cyclind1 and pcna) were observed in TBT-treated fish. In contrast, TBT elevated the expressions of genes involved in meiotic entry and maintenance (aldhla2, sycp3 and dmc1) while suppressed the mRNA level of gene responsible for terminus of meiotic entry (cyp26a1), in agreement with arrested meiosis and reduced sperm count. Furthermore, TBT significantly elevated the ratios of bax/bcl-2 and tnfrsf1a/tnfrsf1b in testis, which are markers for intrinsic- and extrinsic-apoptotic pathways, consistent with the enhanced TUNEL positive signals in spermatocytes. Moreover, TBT also significantly affected the parameter of reproductive behaviors in treated fish (reflected by decreased frequency of meeting, visits and time spent in spawning area). Consistently, the expressions of genes responsible for the modulation of reproductive behaviors in brain (such as cyp19a1b, kiss2, gnrh3 and ompb) were significantly down-regulated in treated-fish. Interestingly, disrupted reproductive behaviors of untreated female fish were also observed in the present study. The present study indicated that TBT might affect the reproduction of zebrafish male by disrupting the spermatogenesis and reproductive behavior of the fish.


Assuntos
Comportamento Sexual Animal/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Meiose/efeitos dos fármacos , Meiose/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Reprodução/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
7.
Chin J Integr Med ; 24(1): 47-55, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28741062

RESUMO

OBJECTIVE: To evaluate anti-melanoma effect of ethanol extract of Ilex hainanensis Merr. (IME) and elucidate its underlying mechanism. METHODS: Thirty-six tumor-bearing mice were randomized into 6 groups (n=6) as follows: model group, IME 25, 50, 100, and 200 mg/kg groups and dacarbazine (DTIC) 70 mg/kg group. The mice in the IME treatment groups were intragastrically administered with IME 25, 50, 100 or 200 mg/kg per day, respectively. The mice in the DTIC group were intraperitoneally injected with DTIC 70 mg/kg every 2 days. The drug administration was lasting for 14 days. The cell viability was evaluated by 3-(4,5-dime-thylthylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay. Flow cytometry was employed to detect cell cycle and apoptosis. The gene and protein expressions of nuclear factor κB-p65 (NF-κB-p65), Bcl-2, B-cell lymphomaextra large (Bcl-xL) and Bax were detected by quantitative real-time polymerase chain reaction and Western blot analyses. Caspases-3, -8, and -9 activities were detected using the colorimetric method. In addition, a B16-F10 melanoma xenograft mouse model was used to evaluate the anti-cancer activity of IME in vivo. Furthermore, a survival experiment of tumor-bearing mice was also performed to evaluate the possible toxicity of IME. RESULTS: IME significantly inhibited the proliferation of B16-F10 cells (P<0.01). Flow cytometric analysis showed that IME induced G1/S cell cycle arrest and apoptosis (both P<0.01). IME inhibited activation of NF-κB, decreased the gene and protein expressions of Bcl-2, Bcl-xL, and increased the gene and protein expressions of Bax (all P<0.01). In addition, IME induced the activation of Caspases-3, -8, and -9 in B16-F10 cells. The study in vivo showed that IME significantly reduced tumor volume (P<0.01), and the inhibitory rate came up to 68.62%. IME also induced large areas of necrosis and intra-tumoral apoptosis that correlated with a reduction in tumor volume. Survival experiment showed that treatment with IME for 14 days significantly prolonged survival time and 20% of mice in the IME 200 mg/kg group were still alive until the 50th day. Notably, IME showed no apparent side-effects during the treatment period. CONCLUSION: IME exhibited significant anti-melanoma activity in vitro and in vivo, suggesting that IME might be a promising effective candidate with lower toxic for malignant melanoma therapy.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Etanol/química , Ilex/química , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Extratos Vegetais/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Masculino , Melanoma Experimental/enzimologia , Melanoma Experimental/genética , Camundongos Endogâmicos C57BL , Necrose , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia , Fase S/efeitos dos fármacos , Análise de Sobrevida
8.
Toxicol Appl Pharmacol ; 315: 90-101, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986624

RESUMO

Recently, we reported that Ilexgenin A exhibits anti-cancer activities and induces cell arrest. Here, we investigated the effect of Ilexgenin A on the inflammation, angiogenesis and tumor growth of hepatocellular carcinoma (HCC). Our current study revealed that Ilexgenin A significantly inhibited the inflammatory cytokines TNF-α and IL-6 levels and downregulated pro-angiogenic factor VEGF production and transcription in HepG2 cells. The underlying mechanism for Ilexgenin A effects appears to be through inhibiting STAT3 and PI3K pathways. Furthermore, we found that not only Ilexgenin A inhibited STAT3 and PI3K pathways in HepG2 cells but also blocked these signaling pathways in HUVECs. Most importantly, by employing two HCC xenografts models - HepG2 and H22, we showed that Ilexgenin A reduced tumor growth and exhibited synergy effect with Sorafenib. ELISA assay, histological analysis and immunohistochemistry examination revealed that the expression of VEGF and MVD was significantly decreased after the treatment with Ilexgenin A and the combination. Moreover, Ilexgenin A could enhance caspase-3/7 activity in vitro and transmission electron microscope indicated that the combination induced evident apoptosis of tumor cells and caused the structural changes of mitochondria in vivo. Although no apparent adverse effects occurred during the treatment period, Sorafenib monotherapy elicited hepatotoxicity for specific expression in the increased level of AST and the ratio of AST/ALT. However, the combination could remedy this adverse effect. In conclusion, the results described in the present study identifies Ilexgenin A as a promising therapeutic candidate that modulates inflammation, angiogenesis, and HCC growth.


Assuntos
Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Triterpenos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Niacinamida/farmacologia , Fosforilação , Sorafenibe
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