Culture on a fragmin/protamine-coated plate suppresses the collagen type IαI and TGF-β1 mRNA expression of rat hepatic stellate RI-T cells

Synthesis and biological evaluation of fluorinated 3,4-dihydroquinolin-2(1H)-ones and 2-oxindoles for anti-hepatic fibrosis

(Z)-4-(Iodomethylene)-3-(2,2,2-trifluoroethyl)-3,4-dihydroquinolin-2(1H)-ones and fluorinated 3,3-disubstituted 2-oxindoles are synthesized and evaluated for anti-hepatic fibrosis. CCK-8 assay indicates that most of the compounds have no obvious cytotoxicity on the human hepatic stellate cells (HSC) cell line. Collagen I and fibrosin expression levels are tested by ELISA, and the results show that several compounds can inhibit the expression of collagen I and fibrosin. Additionally, results from real time-PCR reveal that only one compound can inhibit the expression level of α-SMA, suggesting that this compound can inhibit the activation of the HSC cell line. These studies demonstrate that this compound may be a potential novel drug candidate for anti-hepatic fibrosis (approximately 5-6 lines).

Potentiation of Methylmercury-Induced Death in Rat Cerebellar Granular Neurons Occurs by Further Decrease of Total Intracellular GSH with BDNF via TrkB in Vitro

Brain-derived neurotrophic factor (BDNF) is a principal factor for neurogenesis, neurodevelopment and neural survival through a BDNF receptor, tropomyosin-related kinase (Trk) B, while BDNF can also cause a decrease in the intracellular glutathione (GSH) level. We investigated the exacerbation of methylmercury-induced death of rat cerebellar granular neurons (CGNs) by BDNF in vitro. Since methylmercury can decrease intracellular GSH levels, we hypothesized that a further decrease of the intracellular GSH level is involved in the process of the exacerbation of neuronal cell death. In the present study, we established that in CGN culture, a decrease of the intracellular GSH level was further potentiated with BDNF in the process of the methylmercury-induced neuronal death and also in GSH reducer-induced neuronal death. BDNF treatment promoted the decrease in GSH levels induced by methylmercury and also by L-buthionine sulfoximine (BSO) and diethyl maleate (DEM). The promoting effect of BDNF was observed in a TrkB-vector transformant of the rat neuroblastoma B35 cell line but not in the mock-vector transformant. These results indicate that the exacerbating effect of BDNF on methylmercury-induced neuronal death in cultures of CGNs includes a further decrease of intracellular GSH levels, for which TrkB is essential.

Applications and implications of heparin and protamine in tissue engineering and regenerative medicine

Drug repositioning is one of the most rapidly emerging fields of study. This concept is anchored on the principle that diseases have similar damaged or affected signaling pathways. Recently, drugs have been repositioned not only for their alternative therapeutic uses but also for their applications as biomaterials in various fields. However, medical drugs as biomaterials are rarely focused on in reviews. Fragmin and protamine have been recently the sources of increasing attention in the field of tissue engineering and regenerative medicine. Fragmin and protamine have been manufactured primarily as a safe antidote for the circulating heparin. Lately, these drugs have been utilized as either micro- or nanoparticle biomaterials. In this paper, we will briefly describe the concept of drug repositioning and some of the medical drugs that have been repurposed for their alternative therapeutic uses. Also, this will feature the historical background of the studies focused on fragmin/protamine micro/nanoparticles (F/P M/NPs) and their applications as biomaterials in tissue engineering, stem cell therapy, and regenerative medicine.