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Predicting in vivo efficacy of potential restenosis therapies by cell culture studies: species-dependent susceptibility of vascular smooth muscle cells.

Epstein H, Rabinovich L, Banai S, Elazar V, Gao J, Chorny M, Danenebrg HD, Golomb G - Open Cardiovasc Med J (2008)

Bottom Line: Elucidation of different species sensitivity (rat, rabbit, porcine and human) to diverse drugs (tyrphostins, heparin and bisphsophonates) and a delivery system (nanoparticles) could provide a valuable screening tool for further in vivo studies.The anticipated sensitivity ranking from the explant outgrowth model and SMC mitotic rates (porcine>rat>rabbit>human) do not correlate with the observed relative sensitivity of those animals to antiproliferative therapy in restenosis models (rat>/=rabbit>porcine>human).Similarly, the inhibitory profile of the various antirestenotic drugs in SMC cultures (rabbit>porcine>rat>human) do not correlate with animal studies, the rabbit- and porcine-derived SMC being highly sensitive.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Pharmaceutics, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.

ABSTRACT
Although drug-eluting stents (DES) are successfully utilized for restenosis therapy, the development of local and systemic therapeutic means including nanoparticles (NP) continues. Lack of correlation between in vitro and in vivo studies is one of the major drawbacks in developing new drug delivery systems. The present study was designed to examine the applicability of the arterial explant outgrowth model, and of smooth muscle cells (SMC) cultures for prescreening of possible drugs. Elucidation of different species sensitivity (rat, rabbit, porcine and human) to diverse drugs (tyrphostins, heparin and bisphsophonates) and a delivery system (nanoparticles) could provide a valuable screening tool for further in vivo studies. The anticipated sensitivity ranking from the explant outgrowth model and SMC mitotic rates (porcine>rat>rabbit>human) do not correlate with the observed relative sensitivity of those animals to antiproliferative therapy in restenosis models (rat>/=rabbit>porcine>human). Similarly, the inhibitory profile of the various antirestenotic drugs in SMC cultures (rabbit>porcine>rat>human) do not correlate with animal studies, the rabbit- and porcine-derived SMC being highly sensitive. The validity of in vitro culture studies for the screening of controlled release delivery systems such as nanoparticles is limited. It is suggested that prescreening studies of possible drug candidates for restenosis therapy should include both SMC cell cultures of rat and human, appropriately designed with a suitable serum.

No MeSH data available.


Related in: MedlinePlus

Dose response of inhibitory effect of AG-1295 on SMC from various species. For this experiment cells were plated at 2*104 cells per well in 24-well plates and allowed to grow overnight. Triplicate wells were then treated with rising concentrations of AG-1295 (5-50µM). The cells were then incubated at 37°C for 48hrs and counted using a Coulter counter. AG-1295 caused a marked reduction of SMC proliferation in all species. Note that rabbit and human SMC exhibited the highest and lowest sensitivity. **P<0.001 human vs. other species.
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Figure 4: Dose response of inhibitory effect of AG-1295 on SMC from various species. For this experiment cells were plated at 2*104 cells per well in 24-well plates and allowed to grow overnight. Triplicate wells were then treated with rising concentrations of AG-1295 (5-50µM). The cells were then incubated at 37°C for 48hrs and counted using a Coulter counter. AG-1295 caused a marked reduction of SMC proliferation in all species. Note that rabbit and human SMC exhibited the highest and lowest sensitivity. **P<0.001 human vs. other species.

Mentions: Treatment of SMC of various species in cell culture with tyrphostins resulted in a marked reduction of SMC proliferation. The response to the application of a representative tyrphostin, AG-1295, is depicted in Fig. (4) (similar results were obtained for the other tyrphostins, AG-1296, AG-1851 and AG-2033; data not presented). A similar dose-response relationship was found for all tested species, but with different grades of sensitivity. The ranking of sensitivity was found to be: rabbit>porcine>rat>>human (Fig. 4). As expected, heparin was found to be a potent antiproliferative drug of animal-derived SMC, with sensitivity similar to that obtained with AG-1295 treatment (Fig. 5). No activity of heparin on human-derived SMC was observed, even at the highest concentration of 1000µg/ml (n=4); only 21% inhibition was achiev-ed in comparison to more than 50% inhibition obtained in the rat, rabbit and porcine cultures at <400µg/ml (Fig. 5).


Predicting in vivo efficacy of potential restenosis therapies by cell culture studies: species-dependent susceptibility of vascular smooth muscle cells.

Epstein H, Rabinovich L, Banai S, Elazar V, Gao J, Chorny M, Danenebrg HD, Golomb G - Open Cardiovasc Med J (2008)

Dose response of inhibitory effect of AG-1295 on SMC from various species. For this experiment cells were plated at 2*104 cells per well in 24-well plates and allowed to grow overnight. Triplicate wells were then treated with rising concentrations of AG-1295 (5-50µM). The cells were then incubated at 37°C for 48hrs and counted using a Coulter counter. AG-1295 caused a marked reduction of SMC proliferation in all species. Note that rabbit and human SMC exhibited the highest and lowest sensitivity. **P<0.001 human vs. other species.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2570571&req=5

Figure 4: Dose response of inhibitory effect of AG-1295 on SMC from various species. For this experiment cells were plated at 2*104 cells per well in 24-well plates and allowed to grow overnight. Triplicate wells were then treated with rising concentrations of AG-1295 (5-50µM). The cells were then incubated at 37°C for 48hrs and counted using a Coulter counter. AG-1295 caused a marked reduction of SMC proliferation in all species. Note that rabbit and human SMC exhibited the highest and lowest sensitivity. **P<0.001 human vs. other species.
Mentions: Treatment of SMC of various species in cell culture with tyrphostins resulted in a marked reduction of SMC proliferation. The response to the application of a representative tyrphostin, AG-1295, is depicted in Fig. (4) (similar results were obtained for the other tyrphostins, AG-1296, AG-1851 and AG-2033; data not presented). A similar dose-response relationship was found for all tested species, but with different grades of sensitivity. The ranking of sensitivity was found to be: rabbit>porcine>rat>>human (Fig. 4). As expected, heparin was found to be a potent antiproliferative drug of animal-derived SMC, with sensitivity similar to that obtained with AG-1295 treatment (Fig. 5). No activity of heparin on human-derived SMC was observed, even at the highest concentration of 1000µg/ml (n=4); only 21% inhibition was achiev-ed in comparison to more than 50% inhibition obtained in the rat, rabbit and porcine cultures at <400µg/ml (Fig. 5).

Bottom Line: Elucidation of different species sensitivity (rat, rabbit, porcine and human) to diverse drugs (tyrphostins, heparin and bisphsophonates) and a delivery system (nanoparticles) could provide a valuable screening tool for further in vivo studies.The anticipated sensitivity ranking from the explant outgrowth model and SMC mitotic rates (porcine>rat>rabbit>human) do not correlate with the observed relative sensitivity of those animals to antiproliferative therapy in restenosis models (rat>/=rabbit>porcine>human).Similarly, the inhibitory profile of the various antirestenotic drugs in SMC cultures (rabbit>porcine>rat>human) do not correlate with animal studies, the rabbit- and porcine-derived SMC being highly sensitive.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Pharmaceutics, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 91120, Israel.

ABSTRACT
Although drug-eluting stents (DES) are successfully utilized for restenosis therapy, the development of local and systemic therapeutic means including nanoparticles (NP) continues. Lack of correlation between in vitro and in vivo studies is one of the major drawbacks in developing new drug delivery systems. The present study was designed to examine the applicability of the arterial explant outgrowth model, and of smooth muscle cells (SMC) cultures for prescreening of possible drugs. Elucidation of different species sensitivity (rat, rabbit, porcine and human) to diverse drugs (tyrphostins, heparin and bisphsophonates) and a delivery system (nanoparticles) could provide a valuable screening tool for further in vivo studies. The anticipated sensitivity ranking from the explant outgrowth model and SMC mitotic rates (porcine>rat>rabbit>human) do not correlate with the observed relative sensitivity of those animals to antiproliferative therapy in restenosis models (rat>/=rabbit>porcine>human). Similarly, the inhibitory profile of the various antirestenotic drugs in SMC cultures (rabbit>porcine>rat>human) do not correlate with animal studies, the rabbit- and porcine-derived SMC being highly sensitive. The validity of in vitro culture studies for the screening of controlled release delivery systems such as nanoparticles is limited. It is suggested that prescreening studies of possible drug candidates for restenosis therapy should include both SMC cell cultures of rat and human, appropriately designed with a suitable serum.

No MeSH data available.


Related in: MedlinePlus