The Osmolality and Hemolysis of High-Concentration Monoclonal Antibody Formulations.

PURPOSES: Highly concentrated monoclonal antibody (mAb) formulations for subcutaneous administration are becoming increasingly preferred within the biopharmaceutical industry for ease of use and improved patient compliance. A common phenomenon observed in the industry is that osmolality detected via freezing-point depression (FPD) in high-concentration mAb formulations is much higher than the theoretical concentrations, yet the occurrence of this phenomenon and its possible safety issues have been rarely reported. METHODS: The current study summarized theoretical osmolality of U.S. Food and Drug Administration approved high-concentration mAb formulations and evaluated effects of high osmolality on safety using hemolysis experiments for the first time. Two mAbs formulated at 150 mg/mL were used as models and configured into two isotonic solutions: a, a theoretically calculated molarity in the isotonic range (H) and b, an osmolality value measured via the FPD in the isotonic range (I). The H and I formulations of each mAb were individually subjected to hemolysis experiments, and the hemolysis rates of the two formulations of the same mAb were compared. Besides, the effect of mAb concentration on osmolality detected by FPD was explored as well. RESULTS: The results indicated that the hemolysis rates were similar between the H and I formulations of mAbs at the same sample addition volume, and the osmolality values increased approximately linearly with the increase in mAb concentration. CONCLUSIONS: High osmolality for high-concentration mAb formulations would not affect product safety and the excipients could be added at relatively high levels to maintain product stability, especially for labile products.

ß-elemene inhibits monocyte-endothelial cells interactions via reactive oxygen species/MAPK/NF-κB signaling pathway in vitro.

The recruitment of monocytes to the active endothelial cells is an early step in the formation of atherosclerotic lesions; therefore, the inhibition of monocyte-endothelial cells interactions may serve as a potential therapeutic strategy for atherosclerosis. Recent studies suggest that ß-elemene can protect against atherosclerosis in vivo and vitro; however, the mechanism underlying the anti-atherosclerotic effect by ß-elemene is not clear yet. In this study, we aimed to investigate the effects of ß-elemene on the monocyte-endothelial cells interactions in the initiation of atherosclerosis in vitro. Our results showed that ß-elemene protects human umbilical vein endothelial cells (HUVECs) from hydrogen peroxide-induced endothelial cells injury in vitro. Besides, this molecule inhibits monocyte adhesion and transendothelial migration across inflamed endothelium through the suppression of the nuclear factor-kappa B-dependent expression of cell adhesion molecules. Further, ß-elemene decreases generation of reactive oxygen species (ROS) and prevents the activation of mitogen-activated protein kinase (MAPK) signaling pathway in HUVECs. In conclusion, this study would provide a new pharmacological evidence of the significance of ß-elemene as a future drug for prevention and treatment of atherosclerosis.

Adipose tissue regulates hepatic cholesterol metabolism via adiponectin.

AIMS: Lipid metabolic disorder involves multiple tissues and organs. Hepatic cholesterol metabolism is an important physiological process, which is tightly related to obesity and lipid metabolic disorders. In this study, we examined the direct effects of adipocytes on hepatic cholesterol metabolic factors and investigated the role of potential adipocytokines in it. MAIN METHODS: Male SD rats were induced by a high-fat diet (HFD) and hepatic cholesterol metabolic factors, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) and ATP-binding cassette transporter A1 (ABCA1) were measured by immunoblotting. Then the effects of adipocytes on the expressions of hepatic cholesterol metabolism proteins were examined in the co-culture system. Finally, the concentrations of several adipocytokines were detected by ELISA and the effect of adiponectin (APN) on hepatic cholesterol metabolism was confirmed by short interference RNA (siRNA) in vitro. KEY FINDINGS: Our results showed that adipocytes significantly increased ABCA1 and decreased HMGR in hepatocytes after co-culture. Lipopolysaccharide (LPS) treatment in this co-culture system reversed cholesterol metabolism compared with the untreated group. APN, which also decreased in obese rats, had a significant positive correlation with ABCA1 and inversed correlation with HMGR in vitro. Co-culturing with APN-silenced adipocytes partially restored ABCA1 and HMGR levels. SIGNIFICANCE: The present study demonstrates that adipocytes regulate hepatic cholesterol metabolism partly via APN.

Maslinic acid modulates glycogen metabolism by enhancing the insulin signaling pathway and inhibiting glycogen phosphorylase.

AIM: To investigate the molecular signaling mechanism by which the plant-derived, pentacyclic triterpene maslinic acid (MA) exerts anti-diabetic effects. METHOD: HepG2 cells were stimulated with various concentrations of MA. The effects of MA on glycogen phosphorylase a (GPa) activity and the cellular glycogen content were measured. Western blot analyses were performed with anti-insulin receptor ß (IRß), protein kinase B (also known as Akt), and glycogen synthase kinase-3ß (GSK3ß) antibodies. Activation status of the insulin pathway was investigated using phospho-IRß, as well as phospho-Akt, and phospho-GSK3ß antibodies. The specific PI3-kinase inhibitor wortmannin was added to the cells to analyze the Akt expression. Enzyme-linked immunosorbent assay (ELISA) was used to measure the effect of MA on IRß auto-phosphorylation. Furthermore, the effect of MA on glycogen metabolism was investigated in C57BL/6J mice fed with a high-fat diet (HFD). RESULTS: The results showed that MA exerts anti-diabetic effects by increasing glycogen content and inhibiting glycogen phosphorylase activity in HepG2 cells. Furthermore, MA was shown to induce the phosphorylation level of IRß-subunit, Akt, and GSK3ß. The MA-induced activation of Akt appeared to be specific, since it could be blocked by wortmannin. Finally, MA treatment of mice fed with a high-fat diet reduced the model-associated adiposity and insulin resistance, and increased the accumulated hepatic glycogen content. CONCLUSION: The results suggested that maslinic acid modulates glycogen metabolism by enhancing the insulin signaling pathway and inhibiting glycogen phosphorylase.

Methyl 6-bromo-7-meth-oxy-1,3-benzodioxole-5-carboxyl-ate.

The non-H atoms of the title compound, C(10)H(9)BrO(5), are essentially coplanar, with the exception of the ester group [the O=C-O-C torsion angle is -143.4 (3)°].