Diabetic nephropathy (DN) is a chronic disease characterized by proteinuria, glomerular hypertrophy, decreased glomerular filtration and renal fibrosis with loss of renal function. DN is the leading cause of end-stage renal disease, accounting for millions of deaths worldwide. Hyperglycemia is the driving force for the development of diabetic nephropathy. The exact cause of diabetic nephropathy is unknown, but various postulated mechanisms are: hyperglycemia (causing hyperfiltration and renal injury), advanced glycosylation products, activation of cytokines. In this review article, we have discussed a number of diabetes-induced metabolites such as glucose, advanced glycation end products, protein kinase C and oxidative stress and other related factors that are implicated in the pathophysiology of the DN. An understanding of the biochemical and molecular changes especially early in the DN may lead to new and effective therapies towards prevention and amelioration of DN.

Our study provides evidence that MP formation due to RBC storage might propagate coagulation not only by exposing phosphatidylserine, but also by initiating thrombin generation independently of tissue factor in a FXI -dependent manner.

Asparaginases catalyze the hydrolysis of the amino acid asparagine to aspartate and ammonia. Bacterial asparaginases are used in cancer chemotherapy to deplete asparagine from the blood, since several hematological malignancies depend on extracellular asparagine for growth. To avoid the immune response against the bacterial enzymes it would be beneficial to replace them with human asparaginases. However, unlike the bacterial asparaginases, the human enzymes have a millimolar Km value for asparagine, making them inefficient in depleting the amino acid from blood. To facilitate the development of human variants suitable for therapeutic use, we solved the structure of human L-asparaginase (hASNase3). This asparaginase is an N-terminal nucleophile (Ntn) family member that requires autocleavage between Gly167 and Thr168 to become catalytically competent. For most Ntn-hydrolases this autoproteolytic activation occurs efficiently. In contrast, hASNas3 is relatively stable in its uncleaved state, and this allowed us to observe the structure of the enzyme prior to cleavage. To determine the structure of the cleaved state we exploited our discovery that the free amino acid glycine promotes complete cleavage of hASNase3. Both enzyme states were elucidated in the absence and presence of the product aspartate. Together, these structures provide insight into the conformational changes required for cleavage, and on the precise enzyme-substrate interactions. The new understanding of hASNase3 will serve to guide the design of variants that possess a decreased Km value for asparagine, making the human enzyme a suitable replacement for the bacterial asparaginases in cancer therapy.

Background: Humanized PET reporter gene (PRG) systems are needed to replace immunogenic, viral-derived systems. Results: Employing a structure-guided approach, we developed a highly sensitive humanized PRG characterized by reduced activity for its natural substrates. Conclusion: Sensitivity of PRGs can be improved by reducing their endogenous activities. Significance: Our method can be employed to rapidly develop highly sensitive humanized PRGs.

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