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Delivering minocycline into brain endothelial cells with liposome-based technology.

ABSTRACT: Minocycline has been proposed as a way to blunt neurovascular injury from matrix metalloproteinases (MMPs) during stroke. However, recent clinical trials suggest that high levels of minocycline may have deleterious side-effects. Here, we showed that very high minocycline concentrations damage endothelial cells via calpain/caspase pathways. To alleviate this potential cytotoxicity, we encapsulated minocycline in liposomes. Low concentrations of minocycline could not reduce tumor necrosis factor ? (TNF?)-induced MMP-9 release from endothelial cells. But low concentrations of minocycline-loaded liposomes significantly reduced TNF?-induced MMP-9 release. This study provides proof-of-concept that liposomes may be used to deliver lower levels of minocycline for targeting MMPs in cerebral endothelium.

SUBMITTER: Xing C

PROVIDER: S-EPMC3367232 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Delivering minocycline into brain endothelial cells with liposome-based technology.

Xing Changhong C Levchenko Tatyana T Guo Shuzhen S Stins Monique M Torchilin Vladimir P VP Lo Eng H EH

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20120411 6

Minocycline has been proposed as a way to blunt neurovascular injury from matrix metalloproteinases (MMPs) during stroke. However, recent clinical trials suggest that high levels of minocycline may have deleterious side-effects. Here, we showed that very high minocycline concentrations damage endothelial cells via calpain/caspase pathways. To alleviate this potential cytotoxicity, we encapsulated minocycline in liposomes. Low concentrations of minocycline could not reduce tumor necrosis factor α ...[more]

PMID: 22491155

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Project description:BackgroundMicroparticles (MPs) are small extracellular plasma membrane particles shed by activated and apoptotic cells, which are involved in the development of atherosclerosis. Our previous study found that microRNA (miR)-19b encapsulated within endothelial MPs (EMPs) may contribute to the upregulation of circulating miR-19b in unstable angina patients. Hypoxia is involved in atherosclerosis as a critical pathological stimulus. However, it still remains unclear whether the increase of miR-19b levels in EMPs is related to hypoxia and if the effect of miR-19b - wrapped within EMPs - stimulates hypoxia on vascular endothelial cells. This study aimed to explore the changes of miR-19b in EMPs induced by hypoxia as well as their effects on endothelial cells.MethodsHuman umbilical vein endothelial cells (HUVECs) were cultured in vitro and arranged to harvest EMPs in two parts: the first part consisted of EMPcontrol and EMPhypoxia and the second part included EMPvehicle, EMPNC mimic, and EMPmiR-19b mimic. Cell migration was detected by scratch migration and transwell chamber migration. Angiogenesis was assessed by tube formation assays. Furthermore, we predicted the target gene of miR-19b by bioinformatics analysis, and luciferase assay was used to verify the targeted gene of miR-19b. Data were analyzed by one-way analysis of variance. Student's t-test was used when two groups were compared.ResultsCompared with EMPcontrol- and EMPhypoxia-inhibited migration of cells by scratch migration assay (80.77 ± 1.10 vs. 28.37 ± 1.40, P < 0. 001) and transwell chamber migration assay (83.00 ± 3.46 vs. 235.00 ± 16.52, P < 0.01), the number of tube formations was markedly reduced by 70% in the EMPhypoxia group (P < 0.001) in vitro analysis of HUVECs. Meanwhile, a strong inhibition of migration and tube formation of HUVECs in the presence of miR-19b-enriched EMPmiR-19b mimic was observed. This effect might be due to the delivery of miR-19b in EMPs. Transforming growth factor-?2 (TGF?2) was predicted to be one of the target genes of miR-19b, and we further confirmed that TGF?2 was a direct target gene of miR-19b using the luciferase assay. The expression of TGF?2 in HUVECs was inhibited by treatment with EMPhypoxia and EMPmiR-19b mimic.ConclusionsMiR-19b in EMPs induced by hypoxia could reduce endothelial cell migration and angiogenesis by downregulating TGF?2 expression, which may have inhibited the progression of atherosclerosis.

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Dataset Information

Delivering minocycline into brain endothelial cells with liposome-based technology.

Publications

Delivering minocycline into brain endothelial cells with liposome-based technology.

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