Galectin 1 (Gal-1), a lactose-binding lectin, is a component of vascular extracellular matrix and secreted by human vascular smooth muscle cells (SMCs). The purpose of this study was to investigate a possible role of Gal-1 in controlling adhesion and migration of cultured human vascular SMCs. Gal-1 co-localised with laminin and cellular fibronectin in extracellular matrix (ECM) secreted by cultured human vascular SMCs. Recombinant glutathione S-transferase (GST)-Gal-1 fusion protein bound to laminin and cellular fibronectin in ELISA. GST-Gal-1 inhibited SMC attachment to laminin via interactions with both SMCs and laminin. GST-Gal-1 inhibited SMC spreading on plastic or on laminin, but not on cellular fibronectin. GST-Gal-1 modulated SMC migration on laminin and inhibited migration on cellular fibronectin. GST-Gal-1 bound to several ³⁵S-labelled proteins in SMC extracts including laminin and α1β1 integrin, identified by depletion of SMC protein extracts with respective antibodies. We conclude that Gal-1 is able to modulate SMC attachment, spreading and migration via interactions with ECM proteins and α1β1 integrin.

Hypoparathyroidism (HP) is a condition of parathyroid hormone (PTH) deficiency leading to abnormal calcium and phosphate metabolism. The mainstay of therapy consists of vitamin D and calcium supplements, as well as adjunct Natpara (PTH(1‐84)). However, neither therapy optimally controls urinary calcium (uCa) or significantly reduces the incidence of hypercalcemia and hypocalcemia. TransCon PTH, a sustained‐release prodrug of PTH(1‐34) in development for the treatment of HP, was designed to overcome these limitations. To determine the pharmacokinetics and pharmacodynamics of TransCon PTH, single and repeat s.c. dose studies were performed in rats and monkeys. TransCon PTH demonstrated a half‐life of 28 and 34 hours in rats and monkeys, respectively. After repeated dosing, an infusion‐like profile of the released PTH, characterized by low peak‐to‐trough levels, was obtained in both species. In intact rats and monkeys, daily subcutaneous administration of TransCon PTH was associated with increases in serum calcium (sCa) levels and decreases in serum phosphate levels (sP). In monkeys, at a single dose of TransCon PTH that increased sCa levels within the normal range, a concurrent decrease in uCa excretion was observed. In 4‐week repeat‐dose studies in intact rats and monkeys, uCa excretion was comparable to controls across all dose levels despite increases in sCa levels. Further, in a rat model of HP, TransCon PTH normalized sCa and sP levels 24 hours per day. This was in contrast to only transient trends toward normalization of sCa and sP levels with an up to 6‐fold higher molar dose of PTH(1‐84). After repeated dosing to HP rats, uCa excretion transiently increased, corresponding to increases in sCa above normal range, but at the end of the treatment period, uCa excretion was generally comparable to sham controls. TransCon PTH was well tolerated and the observed pharmacokinetics and pharmacodynamics were in line with the expected action of physiological replacement of PTH. © 2019 American Society for Bone and Mineral Research.

c7E3 Fab inhibits the adhesion and migration of SMCs via the alpha(v)beta(3) integrin. The inhibition, however, is partial, and varied depending on type of ECM protein and alpha(v)beta(3) integrin expression. Some of the clinical benefits of c7E3 Fab may be due to its effect on SMCs.

No abstract