RÉSUMÉ
Aim To investigate the mechanism of high salt-induced cerebral artery remodeling in mice by up-regulating TMEM16A. Methods Forty C57BL/6J mice were randomly divided into four groups (10 per group, 8 weeks of intervention), namely, blank control group (normal diet), low-salt group (2% high salt diet), medium-salt group (4% high salt diet) and high-salt group (8% high salt diet). HE staining was used to observe the morphological changes of cerebral arteries; blood vessel permeability test was used to compare the color and absorbance value of brain tissue. Immunofluorescence was employed to detect TMEM16A expression in cerebral arteries of mice in each group; PCR and Western blot were applied to detect the mRNA and protein expression of TMEM16A in cerebral arterial tissues; whole-cell patch clamp was use to record the calcium-activated chloride channel (CaCC) currents of mouse cerebral artery smooth muscle cells in each group. Results HE results showed that 2%, 4%, and 8% high salt diet could concentra-tion-dependently induce cerebral arterial wall thickening and lumen stenosis in C57BL/6J mice. The permeability test found that compared with the control group, the absorbance value of the brain tissue of the mice in the 2%, 4% and 8% high salt groups increased significantly. The results of isolated muscle tension showed that compared with the control group, the systolic response of isolated cerebral arteries to 60 mmol • L
RÉSUMÉ
A blood-brain barrier microfluidic chip platform for studying the permeability of active components in traditional Chinese medicine was developed. This model used primary human brain microvascular endothelial cells on a microfluidic chip consisting of two perpendicularly-crossing channels and a single layer porous polycarbonate membrane. The physiological shear stress in the human vasculature was also modeled in this device. Cell viability on the chip was monitored by cell staining and immunofluorescence staining. The cells spread well and the structure of an intercellular adhesion protein was satisfactory. The permeability of fluorescent tracers and three model drugs and the functional expression of P-glycoprotein (P-gp)on the blood-brain barrier were investigated. The results show that the apparent permeability coefficients (Papp) of the fluorescent tracers and three model drugs were consistent with those reported in the literature, and P-gp on the chip showed normal function, indicating that there was a complete structure and a functional BBB. The permeability of six active components of traditional Chinese medicine was investigated through this microfluidic chip and the drug concentration was determined by HPLC-MS/MS to obtain the Papp of each component. The Papp of corydaline was (4.51 ± 1.90)×10-7 cm·s-1, the Papp of tetrahydropalmatine was (9.10 ± 6.59)×10-7 cm·s-1, and the Papp of imperatorin was (9.38 ± 2.53)×10-7 cm·s-1; the concentration of isoimperatorin, baicalin and chlorogenic acid was below the limit of quantification, which suggested that isoimperatorin, baicalin and chlorogenic acid have poor permeability in this BBB chip. This blood-brain barrier microfluidic platform possesses a complete barrier function and near-physiological conditions and could be a valuable in vitro tool for drug permeability evaluation.
RÉSUMÉ
To investigate the stability and the conversion rules of cantharidin and cantharidic acid contained in the Mylabris aqueous solution under different conditions. The contents of cantharidin and cantharidic acid under different conditions (pH, temperature and light) were determined by HPLC-TQ-MS. The results showed that the content of cantharidin was gradually decreased with the rising of pH value, while on the contrary, the content of cantharidic acid was increased gradually; after Mylabris aqueous solution with different pH values were placed at 25, 40 ℃ and 25 ℃ respectively for lighting for 90 days, the samples were collected for analysis. The results showed the contents of cantharidin and cantharidic acid were changed greatly in the first 10 days, mainly including the decrease of cantharidic acid and increase of cantharidin when the solution was acidic, and the increase of cantharidic acid and decrease of cantharidin when the solution was alkaline. After that, the contents of the above two components basically remained stable. This study revealed that pH was the main factor to affect the contents of cantharidin and cantharidic acid, and they could be converted into each other with the changes of pH value. High temperature and light can accelerate the speed of achieving such balance. The study can provide certain reference for the quality control of the medicines using the Mylabris as raw material.