A novel trypsin-like protease was purified to homogeneity from the sputum of patients with chronic airway diseases, by sequential chromatographic procedures. The enzyme migrated on SDS-polyacrylamide gel electrophoresis to a position corresponding to a molecular weight of 28 kDa under both reducing and non-reducing conditions, and showed an apparent molecular weight of 27 kDa by gel filtration, indicating that it exists as a monomer. It had an NH2-terminal sequence of Ile-Leu-Gly-Gly-Thr-Glu-Ala-Glu-Glu-Gly-Ser-Trp-Pro-Trp-Gln-Val-Ser-Leu- Arg-Leu, which differed from that of any known protease. Studies with model peptide substrates showed that the enzyme preferentially cleaves the COOH-terminal side of arginine residues at the P1 position of certain peptides, cleaving Boc-Phe-Ser-Arg-4-methylcoumaryl-7-amide most efficiently and having an optimum pH of 8.6 with this substrate. The enzyme was strongly inhibited by diisopropyl fluorophosphate, leupeptin, antipain, aprotinin, and soybean trypsin inhibitor, but hardly inhibited by secretory leukocyte protease inhibitor at 10 microM. An immunohistochemical study indicated that the enzyme is located in the cells of the submucosal serous glands of the bronchi and trachea. These results suggest that the enzyme is secreted from submucosal serous glands onto the mucous membrane in patients with chronic airway diseases.

Previously we isolated a trypsin-like enzyme designated human airway trypsin-like protease from the sputum of patients with chronic airway diseases. This paper describes the cDNA cloning, characterization of the primary protein structure deduced from the cDNA, and gene expression of this enzyme in various human tissues. We obtained an entire 1517-base pair sequence of cDNA with an open reading frame encoding a polypeptide with 418-amino acid residues. The polypeptide consisted of a 232-residue catalytic region and a 186-residue noncatalytic region with a hydrophobic putative transmembrane domain near the NH 2 terminus. The polypeptide was suggested to be a type II integral membrane protein in which the COOH-terminal catalytic region is extracellular. Therefore, this protein is thought to be synthesized as a membrane-bound precursor and to mature to a soluble and active protease by limited proteolysis. It showed 29 -38% identity in the sequence of the catalytic region with human hepsin, enteropeptidase, acrosin, and mast cell tryptase. The noncatalytic region had little similarity to other known proteins. In Northern blot analysis a transcript of 1.9 kilobases was detectable most prominently in the trachea among 17 human tissues examined.

Vitamin D receptor (VDR) ligands are therapeutic agents for the treatment of psoriasis, osteoporosis, and secondary hyperparathyroidism. VDR ligands also show immense potential as therapeutic agents for autoimmune diseases and cancers of skin, prostate, colon, and breast as well as leukemia. However, the major side effect of VDR ligands that limits their expanded use and clinical development is hypercalcemia that develops as a result of the action of these compounds mainly on intestine. In order to discover VDR ligands with less hypercalcemia liability, we sought to identify tissue-selective VDR modulators (VDRMs) that act as agonists in some cell types and lack activity in others. Here, we describe LY2108491 and LY2109866 as nonsecosteroidal VDRMs that function as potent agonists in keratinocytes, osteoblasts, and peripheral blood mononuclear cells but show poor activity in intestinal cells. Finally, these nonsecosteroidal VDRMs were less calcemic in vivo, and LY2108491 exhibited more than 270-fold improved therapeutic index over the naturally occurring VDR ligand 1,25-dihydroxyvitamin D 3 [1,25-(OH) 2 D 3 ] in an in vivo preclinical surrogate model of psoriasis.

SUMMARY1. Isoprenaline (10 nM to 1 /M) and forskolin (06-100 /M) depolarized single guinea-pig myocytes studied in vitro. Under voltage clamp both agents caused an inward current to flow.2. These effects were abolished by propranolol (100 nM) and the /,1-antagonist metoprolol (100-200 nM), but not by the fl2-antagonist salbutamol (1 ,FM).3. The interaction of isoprenaline with forskolin, caffeine or isobutylmethylxanthine (IBMX) on current amplitude was as expected if all of these drugs were causing inward current by increasing intracellular levels of cyclic adenosine monophosphate (cyclic AMP). Low concentrations of forskolin (< 600 nM) or IBMX (< 20 /M) potentiated the effect of isoprenaline, whereas isoprenaline caused no further inward current in cells in which high concentrations of forskolin (600 nM-100 /SM) or IBMX (20 /SM-1 mM) were already evoking maximum inward current.4. Isoprenaline-induced inward current was reduced 30-50 % by acetylcholine (10-30 /tM). This action of acetylcholine was blocked by atropine (100 nM).5. The effect of isoprenaline on holding current was critically dependent on temperature. The onset of the current was delayed and its amplitude reduced as the myocyte was cooled from 37°C to ambient temperature (22-24°C).6. Isoprenaline-induced inward current was not affected by the potassium channel blockers barium (2 mM) or tetraethylammonium (TEA; 10-20 mM). T. M. EGAN AND OTHERS9. The inward current was absent when external sodium was replaced by the impermeant ion tetramethylammonium (TMA).10. Isoprenaline-and forskolin-induced inward currents were associated with an increase in both membrane chord conductance and noise. The increase in conductance was most readily measured at potentials where the inwardly rectifying potassium channel, iK1, was small, or when iKl was blocked by the addition of barium (2 mM).11. The I-V relationship for the total current caused by isoprenaline or forskolin also reflected the effects of these drugs on the calcium current (ica) and the delayed rectifier (iK). When the contributions of ica and iK to the I-V curve were minimized, the remaining inward current reversed at positive potentials. Extrapolation of the linear portion of the I-V curve suggested that the true reversal potential was close to that for sodium.12. These experiments suggest that agents which increase intracellular cyclic AMP open a channel in guinea-pig ventricular sarcolemma which is permeable to sodium ions.

Abstract. Nuclear steroid/thyroid vitamin A/D receptor genes form a gene superfamily and encode DNA-binding transcription factors that control the transcription of target genes in a ligand-dependent manner. It has become clear that chromatin remodeling and the modification of histones, the main components of chromatin, play crucial roles in gene transcription, and many distinct classes of NR-interacting co-regulators have been identified that perform significant roles in gene transcription. Since NR dysfunction can lead to the onset or progression of endocrine disease, elucidation of the mechanisms of gene regulation mediated by NRs, as well as the identification and characterization of co-regulator complexes (especially chromatin remodeling and histone-modifying complexes), is essential not only for better understanding of NR ligand function, but also for pathophysiological studies and the development of therapeutic interventions in humans.

1 Ciguatoxins (CTXs) are known to bind to receptor site 5 of the voltage-dependent Na channel, but the toxin's physiological effects are poorly understood. In this study, we investigated the effects of a ciguatoxin congener (CTX3C) on three different Na-channel isoforms, rNa v 1.2, rNa v 1.4, and rNa v 1.5, which were transiently expressed in HEK293 cells. 2 The toxin (1.0 mmol l À1 ) shifted the activation potential (V 1/2 of activation curve) in the negative direction by 4-9 mV and increased the slope factor (k) from 8 mV to between 9 and 12 mV (indicative of decreased steepness of the activation curve), thereby resulting in a hyperpolarizing shift of the threshold potential by 30 mV for all Na channel isoforms. 3 The toxin (1.0 mmol l À1) significantly accelerated the time-to-peak current from 0.62 to 0.52 ms in isoform rNa v 1.2. Higher doses of the toxin (3-10 mmol l À1) additionally decreased time-to-peak current in rNa v 1.4 and rNa v 1.5. 4 A toxin effect on decay of I Na at À20 mV was either absent or marginal even at relatively high doses of CTX3C. 5 The toxin (1 mmol l À1 ) shifted the inactivation potential (V 1/2 of inactivation curve) in the negative direction by 15-18 mV in all isoforms. 6 I Na maxima of the I-V curve (at À20 mV) were suppressed by application of 1.0 mmol l À1 CTX3C to a similar extent (80-85% of the control) in all the three isoforms. Higher doses of CTX3C up to 10 mmol l À1 further suppressed I Na to 61-72% of the control. 7 Recovery from slow inactivation induced by a depolarizing prepulse of intermediate duration (500 ms) was dramatically delayed in the presence of 1.0 mmol l À1 CTX3C, as time constants describing the monoexponential recovery were increased from 3878 to 5887151 ms (n ¼ 5), 5376 to 338785 ms (n ¼ 4), and 2373 to 2327117 ms (n ¼ 3) in rNa v 1.2, rNa v 1.4, and rNa v 1.5, respectively. 8 CTX3C exerted multimodal effects on sodium channels, with simultaneous stimulatory and inhibitory aspects, probably due to the large molecular size (3 nm in length) and lipophilicity of this membrane-spanning toxin.

This study aimed to elucidate how rats recover from immobilization-induced knee joint contracture. Rats' right knees were immobilized by an external fixator at a flexion of 140° for 3 weeks. After removal of the fixator, the joints were allowed to move freely (remobilization) for 0, 1, 3, 7, or 14 days (n = 5 each). To distinguish myogenic and arthrogenic contractures, the passive extension range of motion was measured before and after myotomy of the knee flexors. Knee joints were histologically analyzed and the expression of genes encoding inflammatory or fibrosis-related mediators, interleukin-1β (1L-1β), fibrosis-related transforming growth factor-β1 (TGF-β1), and collagen type I (COL1A1) and III (COL3A1), were examined in the knee joint posterior capsules using real-time PCR. Both myogenic and arthrogenic contractures were established within 3 weeks of immobilization. During remobilization, the myogenic contracture decreased over time. In contrast, the arthrogenic contracture developed further during the remobilization period. On day 1 of remobilization, inflammatory changes characterized by edema, inflammatory cell infiltration, and upregulation of IL-1β gene started in the knee joint posterior capsule. In addition, collagen deposition accompanied by fibroblast proliferation, with upregulation of TGF-β1, COL1A1, and COL3A1 genes, appeared in the joint capsule between days 7 and 14. These results suggest the progression of arthrogenic contracture following remobilization, which is characterized by fibrosis development, is possibly triggered by inflammation in the joint capsule. It is therefore necessary to focus on developing new treatment strategies for immobilization-induced joint contracture. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1414-1423, 2017.

Grayanotoxin (GTX) exerts selective effects on voltagedependent sodium channels by eliminating fast sodium inactivation and causing a hyperpolarizing shift in voltage dependence of channel activation. In this study, we adopted a newly developed protocol that provides independent estimates of the binding and unbinding rate constants of GTX (k on and k off ) to GTX sites on the sodium channel protein, important in the molecular analysis of channel modification. Novel GTX sites were determined in D2S6 (Asn-784) and D3S6 (Ser-1276) by means of site-directed mutagenesis; the results suggested that the GTX receptor consists of the S6 transmembrane segments of four homologous domains facing the ion-conducting pore. We systematically introduced at two sites in D4S6 (Na v 1.4-Phe-1579 and Na v 1.4-Tyr-1586) amino acid substituents with residues containing hydrophobic, aromatic, charged, or polar groups. Generally, substitutions at Phe-1579 increased both k on and k off , resulting in no prominent change in dissociation constant (K d ). It seems that the smaller the molecular size of the residue at Na v 1.4-Phe-1579, the larger the rates of k on and k off , indicating that this site acts as a gate regulating access of toxin molecules to a receptor site. Substitutions at Tyr-1586 selectively increased k off but had virtually no effect on k on , thus causing a drastic increase in K d . At position Tyr-1586, a hydrophobic or aromatic amino acid side chain was required to maintain normal sensitivity to GTX. These results suggest that the residue at position Tyr-1586 has a more critical role in mediating GTX binding than the one at position Phe-1579. Here, we propose that the affinity of GTX to Na v 1.4 sodium channels might be regulated by two residues (Phe and Tyr) at positions Phe-1579 and Tyr-1586, which, respectively, control access and binding of GTX to its receptor.