Progress in the construction of inner blood retinal barrier model<i> in vitro</i> / 国际眼科杂志(Guoji Yanke Zazhi)

@#The blood-retinal barrier is an important structural basis for maintaining the homeostasis of the retinal environment, but there is still a lack of further research on its complete structure and function. The <i>in vitro</i> blood-retinal barrier model has the characteristics of controllable, efficient, fast and stable, and has become an effective tool to study the specific structure and function of the barrier. This paper mainly reviews the structure, function and <i>in vitro</i> model of blood-retinal barrier, which is helpful to promote the study of physiology, biochemistry, pathopharmacology and clinic of blood-retinal barrier. It also provides a common and key experimental basis for the study of fundus vascular diseases such as diabetic retinopathy.

Effects of Bisphosphonates on Glucose Transport in a Conditionally Immortalized Rat Retinal Capillary Endothelial Cell Line (TR-iBRB Cells)

The objective of the present study was to elucidate the effect of bisphosphonates, anti-osteoporosis agents, on glucose uptake in retinal capillary endothelial cells under normal and high glucose conditions. The change of glucose uptake by pre-treatment of bisphosphonates at the inner blood-retinal barrier (iBRB) was determined by measuring cellular uptake of [3H]3-O-methyl glucose (3-OMG) using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB cells) under normal and high glucose conditions. [3H]3-OMG uptake was inhibited by simultaneous treatment of unlabeled D-glucose and 3-OMG as well as glucose transport inhibitor, cytochalasin B. On the other hand, simultaneous treatment of alendronate or pamidronate had no significant inhibitory effect on [3H]3-OMG uptake by TR-iBRB cells. Under high glucose condition of TR-iBRB cells, [3H]3-OMG uptake was increased at 48 h. However, [3H]3-OMG uptake was decreased significantly by pre-treatment of alendronate or pamidronate compared with the values for normal and high glucose conditions. Moreover, geranylgeraniol (GGOH), a mevalonate pathway intermediate, increased the uptake of [3H]3-OMG reduced by bisphosphonates pre-treatment. But, pre-treatment of histamine did not show significant inhibition of [3H]3-OMG uptake. The glucose uptake may be down regulated by inhibiting the mevalonate pathway with pre-treatment of bisphosphonates in TR-iBRB cells at high glucose condition.

Research progress of diabetes on the ultrastructure of blood retina barrier / 国际眼科杂志(Guoji Yanke Zazhi)

Diabetic retinopathy is a major cause of blindness all over the world, and it is one of the most serious and common microvascular complications of diabetes. Breakdown of the endothelial blood - retinal barrier ( BRB ) , as occurs in diabetic retinopathy, result in vasogenic edema and neural tissue damage, causing loss of vision. The inner BRB is created by complex tight juctions of retinal capillary endothelial cells, this barrier prevents the free diffusion of substances between the circulating blood and the neural retinal, the inner BRB efficiently supplies nutrients to the retinal and removes endobiotics and xenobiotics from the retina to maintain a constant milieu in the neural retina. The central mechanism of altered inner BRB function is a change in the permeability characteristics of retinal endothelial cells caused by elevated levels of cytokines, growth factors, advanced glycation end products, inflammation, hyperglycema and loss of pericytes. This article reviews the relationship between diabetes and the ultrastructure changes of BRB.