ABSTRACT
Blood brain barrier (BBB), as barrier between plasma and brain cells formed by brain capillary wall and glial cells and barrier between plasma and cerebrospinal fluid formed by choroid plexus, can prevent some brain tissues (mostly harmful substances), so as to maintain a stable internal environment of brain tissues, while stopping most drugs from the intracranial and causeing difficulties to cerebral diseases. The establishment of experimental model of BBB is a key technique for drug treatment of craniocerebral diseases. Therefore, the establishment of the BBB model and the study of its permeability change will deepen the understanding of the neuro-vascular interaction and provide an important theoretical basis for the diagnosis and treatment of central nervous system diseases. Traditional Chinese medicine(TCM) can affect brain tissue superoxide dismutase (SOD) activity, inhibit myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) content, so as to affect the expression of zonula occluden-1 (ZO-1) or up-regulate the expression of Claudin-5, inhibit BBB permeability under pathological conditions, and play a protective role in BBB. TCM can also promote the changes in BBB permeability by affecting the expressions of cell adhesion factor-1 (CAM-1), ZO-1, filamentous actin(F-actin), P-glycoprotein(P-gp)and 5-hydroxytryptamine (5-HT), or increase drug permeability through co-delivery with other drugs. In this paper, the methods, advantages and disadvantages of the establishment of experimental models of the BBB in recent years, as well as the effects of TCM monomers, effective components and TCM compounds on the permeability of the BBB were summarized, so as to provide important guidance and direction for the future treatment of intracranial diseases by traditional Chinese and western medicine.
ABSTRACT
Liver disease is the general term for all diseases that occur in the liver. In recent years, traditional Chinese medicine has certain advantages in the treatment of liver diseases. With a high experimental study value, good clinical efficacy and less adverse reactions, it has broad prospects. Toll-like receptor 4 (TLR4) signaling pathway is closely related to liver diseases. Its mechanism is to activate nuclear factor-κB (NF-κB) through tlr4-mediated signaling pathway, inhibit the secretion of such inflammatory factors as interleukin-1(IL-1), interleukin-6(IL-6) and tumor necrosis factor-alpha (TNF-α), and the inflammatory damage of liver cells, so as to further inhibit the effect of IL-1,IL-6, TNF-α in activating Hepatic Stellate Cell(HSC). The ways of blocking TRL4 pathway are as follows:Inhibiting the expression of TLR4,Inhibiting the dimerization of TLR4. Blocking intracellular signal transduction:①acting on the binding protein; ②acting on the kinase IRAKs; ③acting on TLRAFst. In these ways, the TRL4 pathway is blocked, the inflammation is inhibited, and the anti-liver disease effect is achieved. Therefore, inhibiting or enhancing TLR4 signaling pathway or intervening in some links of TLR4 signaling pathway has become a new strategy for the treatment of liver diseases. Toll-like receptor 4 signaling pathway has become one of the targets of traditional Chinese medicine (TCM) against liver diseases. In this paper, the recent literatures on the effect of TCM in resisting activation of TLR4 signaling pathway and the effect of anti-liver diseases through monomers and effective parts of TCM, extracts of TCM and compound prescriptions of TCM were collected and summarized to provide important guiding significance and direction for the treatment of liver diseases by TCM and WM in the next step.