Case of homozygous familial hypercholesterolaemia with premature coronary artery disease.

Familial hypercholesterolaemia is a genetic disorder secondary to mutation of one or more of the genes critical for low-density lipoprotein cholesterol (LDL-C) metabolism; these mutation(s) cause highly elevated serum LDL-C, significantly increasing the risk of early cardiovascular events and mortality. Homozygous familial hypercholesterolaemia (HoFH) is rare and often leads to accelerated coronary atherosclerosis presenting within the first two decades of life. We report a case of a 14-year-old boy who presented after surviving a ventricular fibrillation cardiac arrest. His highly elevated LDL-C level prompted further workup and led to a diagnosis of HoFH. The treatment included medical therapy and coronary artery bypass grafting. The patient also required referral for lipid apheresis to meet goal LDL-C level, and an automated implantable cardioverter defibrillator for secondary prevention of sudden cardiac death. HoFH, if left untreated, can have devastating consequences Therefore, timely diagnosis initiating appropriate therapy is important.

Design of a thrombin resistant human acidic fibroblast growth factor (hFGF1) variant that exhibits enhanced cell proliferation activity.

Acidic fibroblast growth factors (FGF1s) are heparin binding proteins that regulate a wide array of key cellular processes and are also candidates for promising biomedical applications. FGF1-based therapeutic applications are currently limited due to their inherent thermal instability and susceptibility to proteases. Using a wide range of biophysical and biochemical techniques, we demonstrate that reversal of charge on a well-conserved positively charged amino acid, R136, in the heparin binding pocket drastically increases the resistance to proteases, thermal stability, and cell proliferation activity of the human acidic fibroblast growth factor (hFGF1). Two-dimensional NMR data suggest that the single point mutations at position-136 (R136G, R136L, R136Q, R136K, and R136E) did not perturb the backbone folding of hFGF1. Results of the differential scanning calorimetry experiments show that of all the designed R136 mutations only the charge reversal mutation, R136E, significantly increases (ΔTm = 7 °C) the thermal stability of the protein. Limited trypsin and thrombin digestion results reveal that the R136E mutation drastically increases the resistance of hFGF1 to the action of the serine proteases. Isothermal titration calorimetry data show that the R136E mutation markedly decreases the heparin binding affinity of hFGF1. Interestingly, despite lower heparin binding affinity, the cell proliferation activity of the R136E variant is more than double of that exhibited by either the wild type or the other R136 variants. The R136E variant due to its increased thermal stability, resistance to proteases, and enhanced cell proliferation activity are expected to provide valuable clues for the development of hFGF1- based therapeutics for the management of chronic diabetic wounds.