Selective phytochemicals targeting pancreatic stellate cells as new anti-fibrotic agents for chronic pancreatitis and pancreatic cancer

Activated pancreatic stellate cells (PSCs) have been widely accepted as a key precursor of excessive pancreatic fibrosis, which is a crucial hallmark of chronic pancreatitis (CP) and its formidable associated disease, pancreatic cancer (PC). Hence, anti-fibrotic therapy has been identified as a novel therapeutic strategy for treating CP and PC by targeting PSCs. Most of the anti-fibrotic agents have been limited to phase I/II clinical trials involving vitamin analogs, which are abundant in medicinal plants and have proved to be promising for clinical application. The use of phytomedicines, as new anti-fibrotic agents, has been applied to a variety of complementary and alternative approaches. The aim of this review was to present a focused update on the selective new potential anti-fibrotic agents, including curcumin, resveratrol, rhein, emodin, green tea catechin derivatives, metformin, eruberin A, and ellagic acid, in combating PSC in CP and PC models. It aimed to describe the mechanism(s) of the phytochemicals used, either alone or in combination, and the associated molecular targets. Most of them were tested in PC models with similar mechanism of actions, and curcumin was tested intensively. Future research may explore the issues of bioavailability, drug design, and nano-formulation, in order to achieve successful clinical outcomes with promising activity and tolerability.

Signal enhancement in ELISA: Biotin-streptavidin technology against gold nanoparticles

Objectives: The aim of this study is to compare the use of biotin-streptavidin and gold nanoparticle [GNP] technologies in enzyme linked immunosorbent assay [ELISA] techniques to improve its sensitivity and accuracy

Methods: We evaluated two ELISA methods to improve the sensitivity and accuracy. Biotin-streptavidin technology was selected to enhance the ELISA limit of detection due to the high binding affinity of biotin-streptavidin. GNP-conjugated biomolecules were selected to improve detection by ELISA. To evaluate these two methods, the early secreted antigenic target-6 [ESAT-6] from Mycobacterium tuberculosis and the anti-ESAT-6 antibody were used

Results: The detection limit of ESAT-6 was the same with and without GNP due to the saturation of biotin and streptavidin binding. However, higher absorbance was noticed using GNP only

Conclusion: The proposed modified ELISA can be used to screen different types of common diseases. Additionally, this study showed how several new techniques can improve the detection and accuracy of ELISA