Triphenyltin acetate toxicity : a biochemical and ultrastructural study on mouse thymocytes

1996 ◽  
Vol 15 (3) ◽  
pp. 219-225 ◽  
Author(s):  
E. Bollo ◽  
L. Ceppa ◽  
E. Cornaglia ◽  
C. Nebbia ◽  
B. Biolatti ◽  
...  

1 Triphenyltin acetate (TPTA) has been shown to exert in vivo a selective toxic effect on the immune system. To assess in vitro possible alterations induced by TPTA exposure, primary cultures of mouse thymocytes were incubated up to 24 h with graded amounts (1-12 μM) ofthe organotin. 2 The cytotoxic activity has been evaluated with the MTT colorimetric assay, the neutral red (NR) assay and the lactic dehydrogenase (LDH) cellular release. Cell pellets were fixed with 2.5% glutaraldehyde, resin-embedded and ultrathin sections were observed through transmission electron microscopy. 3 After 2 h of incubation, dose-dependent increases of cytotoxicity were observed in thymocytes submitted to MTT and NR tests (up to 41.43% and 18.9%, respectively), while 22 h later this overt effect on cell viability was noticed merely in cells exposed to 12 μM TPTA. Dose- dependent increases of LDH leakage in the culture medium were observed all throughout the study. 4 Morphological investigations revealed features (chro matin condensation, cell membranes fragmentation and formation of membrane bound apoptotic bodies) sugges tive of apoptosis. 5 This study indicates that TPTA is cytotoxic to mouse thymocytes: morphologically, the rising of apoptosis is likely to be recognized, as previously reported in different in vitro studies with other immunosuppressive agents as dioxin and corticosteroids.

1970 ◽  
Vol 132 (6) ◽  
pp. 1055-1070 ◽  
Author(s):  
Irun R. Cohen ◽  
Lary Stavy ◽  
Michael Feldman

We studied the influence of glucocorticoids on the sensitization phase as well as on the cytolytic effector phase of an in vitro lymphocyte-mediated immune reaction. Lymphocytes obtained from the spleens or lymph nodes of unimmunized inbred rats were sensitized against foreign rat or mouse embryonic fibroblasts in cell culture. The capacity of the sensitized lymphocytes to produce a cytolytic effect was tested by transferring them to target fibroblast cultures. Injury to target fibroblasts was measured by release of radioactive 51Cr from previously labeled fibroblasts or by direct count of viable fibroblasts after incubation with sensitized lymphocytes. Various concentrations of water-soluble hydrocortisone or prednisolone were added to cell cultures during the 5 day sensitization phase and/or during the subsequent cytolytic effector phase and the influence of these hormones on the number and cytolytic capacity of the lymphocytes was measured. During the sensitization phase, the presence of glucocorticoid hormones, at concentrations of about 1 µg/ml, led to a profound decrease in the total number of recoverable lymphocytes. However, the per cent of large transformed lymphocytes was much greater in these treated cultures. The antigen-specific cytolytic capacity per cell of the glucocorticoid-treated lymphocytes, after the hormone was removed, was several times greater than that of lymphocytes sensitized in the absence of added hormones. Glucocorticoids influenced the effector phase of the reaction by inhibiting lymphocyte-mediated injury to target fibroblasts. The hormones, at concentrations of about 1 µg/ml, inhibited the cytolytic effect by about 50% without reducing the viability of the sensitized lymphocytes. Dose-dependent toxicity to lymphocytes and increasing inhibition of cytolytic effect appeared at higher concentrations of hormones. Thus, hydrocortisone and prednisolone, at concentrations of about 1 µg/ml, did not suppress the induction of sensitization, a process which they seem to facilitate in vitro. However, similar concentrations of these hormones appear to inhibit the cytolytic effector mechanism of sensitized lymphocytes. These findings may be relevant to the use of glucocorticoids as immunosuppressive agents in vivo.


2014 ◽  
Vol 42 (04) ◽  
pp. 833-852 ◽  
Author(s):  
Yung-Wei Chiu ◽  
Pei-Yu Chao ◽  
Chin-Chiu Tsai ◽  
Hui-Ling Chiou ◽  
Yuh-Chyan Liu ◽  
...  

Ocimum gratissimum is a traditional herb commonly found in tropical regions, which prevents free radical damage and protects the liver from oxidative stress. In this study, we tested in vivo and in vitro the effectiveness of O. gratissimum extracts (OGEs) in anti-hepatic fibrosis in rats. Male Wistar rats were administered with carbon tetrachloride (CCl4) by intraperitoneal injection and varying amounts of oral injection of OGE doses (0–40 mg/kg body weight) for 8 weeks. Our experiments showed that OGE significantly reduced liver damage, including steatosis and fibrosis, in a dose-dependent manner, as well as significantly decreased the elevation in plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It also inhibited the formation of lipid peroxidative products during CCl4 treatment. Moreover, OGE-inhibited CCl4-induced liver collagen accumulation and promoted the expression of catalase, an anti-oxidative enzyme. The inhibition of fibrosis factors α-SMA expression was also observed. In primary cultures, OGE significantly inhibited the serum-induced activation of hepatic stellate cells (HSCs), and the expression of α-SMA and collagen α (I). These data suggest that O. gratissimum possesses anti-hepatic fibrosis properties via its anti-oxidative components.


1992 ◽  
Vol 20 (1) ◽  
pp. 8-26
Author(s):  
Anne-Françoise Peloux ◽  
Christian Fédérici ◽  
Nicole Bichet ◽  
Daniel Gouy ◽  
Jean-Paul Cano

The cytotoxicity of 30 chemicals was assessed in rat hepatocyte primary cultures using four methods: lactate dehydrogenase release, neutral red uptake, the MTT assay, and measurement of total protein content. Comparison of the data obtained in vitro (IC50 values) and in vivo (LD50 values) resulted in a significant correlation (p<0.001) between IC50 values and intravenous LD50 values. The validity, as well as the predictability of the model, were determined by multivariate analysis (principal component analysis and correspondence analysis). The predictability area, expressed in IC50 values, was in the range of 0–l,500μg/ml and reached 95%, with a 75–100% confidence interval (p = 0.05). Assessment of the cytotoxicity of 54 additional chemicals would provide a more accurate predictability limit around l,500μg/ml and the estimated predictability confidence interval could be reduced to 90–100%.


1995 ◽  
Vol 73 (05) ◽  
pp. 805-811 ◽  
Author(s):  
Yasuo Takahashi ◽  
Yoshitaka Hosaka ◽  
Hiromi Niina ◽  
Katsuaki Nagasawa ◽  
Masaaki Naotsuka ◽  
...  

SummaryWe examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity >5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (>1 TMU/ml), APTT (>5 TMU/ml), TT (>5 TMU/ml) and PT (>40 TMU/ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.


Author(s):  
Mohammed Ajebli ◽  
Mohamed Eddouks

Aims and objective: The aim of the study was to investigate the effect of aqueous aerial part extract of Mentha pulegium L. (Pennyrile) (MPAE) on arterial pressure parameters in rats. Background: Mentha pulegium is a medicinal plant used to treat hypertension in Morocco. Material and methods: In the current study, MPAE was prepared and its antihypertensive activity was pharmacologically investigated. L-NAME-hypertensive and normotensive rats have received orally MPAE (180 and 300 mg/kg) during six hours for the acute experiment and during seven days for the sub-chronic treatment. Thereafter, systolic, diastolic, mean arterial blood pressure and heart rate were evaluated. While, in the in vitro experiment, isolated denuded and intact thoracic aortic rings were suspended in a tissue bath system and the tension changes were recorded. Results: A fall in blood pressure was observed in L-NAME-induced hypertensive treated with MPAE. The extract also produced a dose-dependent relaxation of aorta pre-contracted with NE and KCl. The study showed that the vasorelaxant ability of MPAE seems to be exerted through the blockage of extracellular Ca2+ entry. Conclusion: The results demonstrate that the extract of pennyrile exhibits antihypertensive activity. In addition, the effect may be, at least in part, due to dilation of blood vessels via blockage of Ca2+ channels.


1997 ◽  
Vol 25 (2) ◽  
pp. 153-160
Author(s):  
Francesca Mattioli ◽  
Marianna Angiola ◽  
Laura Fazzuoli ◽  
Francesco Razzetta ◽  
Antonietta Martelli

Although primary cultures of human thyroid cells are used for endocrinological and toxicological studies, until now no attention has been paid toward verifying whether the hormonal conditions to which the gland was exposed in vivo prior to surgery could influence in vitro responses. Our findings suggest that the hormonal situation in vivo cannot be used as a predictive indicator of triiodothyronine and thyroxine release and/or S-phase frequency in vitro, either with or without the addition of bovine thyrotropin.


2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Xuxing Shen ◽  
Chao Wu ◽  
Meng Lei ◽  
Qing Yan ◽  
Haoyang Zhang ◽  
...  

AbstractCarfilzomib, a second-generation proteasome inhibitor, has significantly improved the survival rate of multiple myeloma (MM) patients, but its clinical application is still restricted by drug resistance and cardiotoxicity. Here, we identified a novel proteasome inhibitor, D395, and assessed its efficacy in treating MM as well as its cardiotoxicity at the preclinical level. The activities of purified and intracellular proteasomes were measured to determine the effect of D395 on the proteasome. CCK-8 and flow cytometry experiments were designed to evaluate the effects of D395 on cell growth and apoptosis. The effects of D395 and carfilzomib on serum enzyme activity, echocardiography features, cardiomyocyte morphology, and hERG channels were also compared. In our study, D395 was highly cytotoxic to MM cell lines and primary MM cells but not normal cells, and it was well tolerated in vivo. Similar to carfilzomib, D395 inhibited osteoclast differentiation in a dose-dependent manner. In particular, D395 exhibited lower cardiotoxicity than carfilzomib in all experiments. In conclusion, D395 is a novel irreversible proteasome inhibitor that has remarkable anti-MM activity and mild cardiotoxicity in vitro and in vivo.


1998 ◽  
Vol 26 (5) ◽  
pp. 679-708 ◽  
Author(s):  
Horst Spielmann ◽  
Michael Balls ◽  
Jack Dupuis ◽  
Wolfgang J. W. Pape ◽  
Odile de Silva ◽  
...  

In 1996, the Scientific Committee on Cosmetology of DGXXIV of the European Commission asked the European Centre for the Validation of Alternative Methods to test eight UV filter chemicals from the 1995 edition of Annex VII of Directive 76/768/EEC in a blind trial in the in vitro 3T3 cell neutral red uptake phototoxicity (3T3 NRU PT) test, which had been scientifically validated between 1992 and 1996. Since all the UV filter chemicals on the positive list of EU Directive 76/768/EEC have been shown not to be phototoxic in vivo in humans under use conditions, only negative effects would be expected in the 3T3 NRU PT test. To balance the number of positive and negative chemicals, ten phototoxic and ten non-phototoxic chemicals were tested under blind conditions in four laboratories. Moreover, to assess the optimum concentration range for testing, information was provided on appropriate solvents and on the solubility of the coded chemicals. In this study, the phototoxic potential of test chemicals was evaluated in a prediction model in which either the Photoirritation Factor (PIF) or the Mean Photo Effect (MPE) were determined. The results obtained with both PIF and MPE were highly reproducible in the four laboratories, and the correlation between in vitro and in vivo data was almost perfect. All the phototoxic test chemicals provided a positive result at concentrations of 1μg/ml, while nine of the ten non-phototoxic chemicals gave clear negative results, even at the highest test concentrations. One of the UV filter chemicals gave positive results in three of the four laboratories only at concentrations greater than 100μg/ml; the other laboratory correctly identified all 20 of the test chemicals. An analysis of the impact that exposure concentrations had on the performance of the test revealed that the optimum concentration range in the 3T3 NRU PT test for determining the phototoxic potential of chemicals is between 0.1μg/ml and 10μg/ml, and that false positive results can be obtained at concentrations greater than 100μg/ml. Therefore, the positive results obtained with some of the UV filter chemicals only at concentrations greater than 100μg/ml do not indicate a phototoxic potential in vivo. When this information was taken into account during calculation of the overall predictivity of the 3T3 NRU PT test in the present study, an almost perfect correlation of in vitro versus in vivo results was obtained (between 95% and 100%), when either PIF or MPE were used to predict the phototoxic potential. The management team and participants therefore conclude that the 3T3 NRU PT test is a valid test for correctly assessing the phototoxic potential of UV filter chemicals, if the defined concentration limits are taken into account.


2021 ◽  
Vol 10 (1) ◽  
pp. 101-111
Author(s):  
Rehman Ullah ◽  
Sumaira Shah ◽  
Zahir Muhammad ◽  
Sajjad Ali Shah ◽  
Shah Faisal ◽  
...  

Abstract The current study was designed to investigate the potential of Euphorbia wallichii shoot extract for reducting Au3+ and stabilizing gold nanoparticles. UV-visible spectra of gold nanoparticles showed obvious surface plasmon resonance peak at 548 nm. Microscopy (SEM and TEM) showed spherical dimensions, and the energy dispersive X-ray spectra displayed the strongest optical absorption peak for gold (Au) at 2.1 keV. Dynamic light scattering spectra represent polydispersed mixture with particulate diameter of 2.5–103.2 nm. The IR spectra confirm the potential functional groups of shoot extract responsible for the reduction of Au3+ to gold nanoparticles which exhibit tremendous antibacterial potential of 76.31%, 68.47%, 79.85%, 48.10%, and 65.53% against Escherichia coli, Staphylococcus aureus, Bacillus pumilus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, respectively. Gold nanoparticles showed markedly elevated fungicidal potency compared to the shoot extract alone against the tested fungal strains. IC50 for 2,2-diphenyl-1-picrylhydrazyl scavenging was 31.52, 18.29, and 15.32 µg/mL at 30, 60, and 90 min of reaction time, respectively. Both shoot extract and nanoparticles revealed 71% mortality at 100 µg/mL, with LD90 values of 310.56 µg/mL. Experimental mice acquired dose-dependent analgesia of 54.21%, 82.60%, and 86.53% when treated with gold nanoparticles at 50, 100, and 200 mg/kg bw. Inhibition of gastrointestinal muscular contraction was 21.16%, 30.49%, and 40.19% in mice feed with 50, 100, and 200 mg/kg bw, respectively.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).


Sign in / Sign up

Export Citation Format

Share Document