Discovery and pharmacological characterization of SAR707 as novel and selective small molecule inhibitor of stearoyl-CoA desaturase (SCD1).

Stearoyl-CoA desaturase (SCD1) is linked to the pathogenesis of obesity, dyslipidemia and type 2 diabetes. It is the rate-limiting enzyme in the synthesis of monounsaturated 16:1 n-7 and 18:1 n-9 fatty acyl-CoAs and catalyzes an essential part of lipogenesis. Here, we describe the identification, in vitro properties and in vivo efficacy of a novel class of heterocyclic small molecule hexahydro-pyrrolopyrrole SCD1 inhibitors. SAR707, a compound representative for the series, was optimized to high in vitro potency, selectivity and favorable overall properties in enzymatic and cellular assays. In vivo, this compound reduced serum desaturation index, decreased body weight gain and improved lipid parameters and blood glucose levels of obese Zucker diabetic fatty rats treated for 4 weeks in a chronic study. In parallel, fissures of the eye lid, alopecia and inflammation of the skin were observed from day 11 on in all animals treated with the same metabolically active dose. In summary, we described in vitro and in vivo properties of a novel, potent and selective SCD1 inhibitor that improved body weight, blood glucose and triglycerides in an animal model of obesity, type 2 diabetes and dyslipidemia. However, the favorable in vivo properties of systemic SCD1 inhibition shown in our study were accompanied by dose-dependently occurring adverse target-related effects observed in skin. Thus, systemic SCD1 inhibition by small molecules might therefore not represent a feasible approach for the treatment of chronic metabolic diseases.

Benzimidazole-carboxamides as potent and bioavailable stearoyl-CoA desaturase (SCD1) inhibitors from ligand-based virtual screening and chemical optimization.

The discovery of potent benzimidazole stearoyl-CoA desaturase (SCD1) inhibitors by ligand-based virtual screening is described. ROCS 3D-searching gave a favorable chemical motif that was subsequently optimized to arrive at a chemical series of potent and promising SCD1 inhibitors. In particular, compound SAR224 was selected for further pharmacological profiling based on favorable in vitro data. After oral administration to male ZDF rats, this compound significantly decreased the serum fatty acid desaturation index, thus providing conclusive evidence for SCD1 inhibition in vivo by SAR224.

Identification and synthesis of novel inhibitors of acetyl-CoA carboxylase with in vitro and in vivo efficacy on fat oxidation.

Acetyl CoA carboxylase isoforms 1 and 2 (ACC1/2) are key enzymes of fat utilization and their inhibition is considered to improve aspects of the metabolic syndrome. To identify pharmacological inhibitors of ACC1/2, a high throughput screen was performed which resulted in the identification of the lead compound 3 ( Gargazanli , G. ; Lardenois , P. ; Frost , J. ; George , P. Patent WO9855474 A1, 1998 ) as a moderate selective ACC2 inhibitor. Optimization of 3 led to 4m ( Zoller , G. ; Schmoll , D. ; Mueller , M. ; Haschke , G. ; Focken , I. Patent WO2010003624 A2, 2010 ) as a submicromolar dual ACC1/2 inhibitor of the rat and human isoforms. 4m possessed favorable pharmacokinetic parameters. This compound stimulated fat oxidation in vivo and reduced plasma triglyceride levels in a rodent model after subchronic administration. 4m is a suitable tool compound for the elucidation of the pharmacological potential of ACC1/2 inhibition.

Changes of microvascular perfusion during acute ureteral obstruction in the rat kidney - the influence of gastrin releasing peptide.

INTRODUCTION: Peritubular renal microcirculation has not been directly visualized in acute ureteral obstruction. Therefore, we used epiilluminescence intravital microscopy and an animal model for the assessment of microvascular perfusion. MATERIALS AND METHODS: In group 1 (n = 5) the left kidney of Wistar rats was exteriorized and placed on a heatable stage for microcirculatory analysis. FITC-dextran was injected for plasma staining. Microcirculatory stability of the model was assessed by a repeated intravital microscopy at baseline, 60, and 120 minutes. In detail, the functional peritubular vessel density (FVD, total vessel length per area in cm/cm(2)), the red blood cell velocities and diameters in/of arterioles and peritubular capillaries and the perfusion index were measured. In group 2 (n = 7) the left ureter was obstructed after baseline microscopy. In a third group (n = 6) the influence of the antidiuretic and vasoconstrictive peptide gastrin releasing peptide on peritubular microcirculation of the obstructed kidney was measured. RESULTS: Repeated intravital microscopy did not induce major microcirculatory disturbances in group 1. Acute ureteral obstruction significantly decreased the index of peritubular perfusion. Moreover, FVD was found decreased at 120 minutes after a small rise at 60 minutes. Whereas blood cell velocities were not changed, arteriolar diameters were decreased after 120 minutes. GRP infusion lowered intrapelvic pressures at 60 and at 120 minutes. The transient increase of FVD (group 2) was not observed. The calculated peritubular flow remained nearly constant compared to a decrease in group 2. Histological assessment did not reveal any microscopy induced renal damage nor any differences between the groups. CONCLUSIONS: (1) The model is stable for a time period of at least 120 minutes and allows for the direct visualization of the renal peritubular vessels. (2) Peritubular microcirculation shows a significant deterioration during ureteral obstruction. (3) Infusion of GRP may be beneficial for the microcirculation of the acutely obstructed kidney.

Alteration of the vascular endothelial growth factor and angiopoietins-1 and -2 pathways in transitional cell carcinomas of the urinary bladder associated with tumor progression.

Neoangiogenesis is assumed to play an important role in the progression, metastasis and prognosis of a wide variety of tumors. To get insights into the molecular-genetic pathways and the biological role of angiogenesis in urothelial carcinogenesis, we analyzed comparatively the expression of the mRNA of the vascular endothelial growth factor (VEGF) and of the angiopoietins-1 and -2 (Ang-1 and Ang-2) in 71 transitional cell carcinomas (TCC) of the urinary bladder in relation to the tumor grades and stages, and referring to epidemiological risk factors. Using real-time quantitative reverse transcription-polymerase chain reaction, low-stage superficial TCC expressed VEGF and Ang-2 mRNA at a significantly higher level than high-stage muscle invasive carcinomas, and low-grade TCC at an insignificantly higher level than high-grade tumors. The activity of both angiogenic factors was found to be significantly correlated. Conversely, Ang-1 mRNA was expressed at a 3-fold significantly lower level in low-grade, low-stage compared to high-grade, high-stage TCC. A significantly 3- and 2-fold respectively, drop of the VEGF and Ang-2 mRNA expression in conjunction with a 2-fold significantly higher expression of Ang-1 mRNA in the group of grade 2 TCC when infiltrating the muscle layer may represent a crucial event during urothelial carcinogenesis, and possibly indicates an important step in promoting the conversion of bladder cancer from a low to a high malignancy in this subset of carcinomas. By immunhistochemistry, high-grade, high-stage carcinomas less frequently displayed areas with a strong reactivity for the VEGF protein ('hot spots") than low-grade, low-stage TCC, paralleling the expression of the mRNA. The expression patterns observed are compatible with a reduced vascular destabilization and decreased formation of new blood vessels in advanced TCC, suggesting a balance between vessel regression and vascular growth, with a less pronounced vascular remodeling during late phases of urothelial carcinogenesis. Analyzing the effect of life-style bladder cancer risk factors, habitual smoking and coffee consumption was not observed to substantially alter the expression of the angiogenic mediators, except for weakly elevated levels of VEGF and Ang-2 mRNA in TCC of strong smokers and a borderline significantly decreased VEGF mRNA expression associated with heavy coffee consumption. Certain hazardous occupational exposures (polycyclic hydrocarbons, paints and lacquer, stone dust) may play a role in modulating tumor angiogenesis. The current data indicate that the signaling molecular-genetic pathways underlying vascular remodeling are involved in the progression of urinary bladder cancer to a more malignant and aggressive behaviour.

Novel factor Xa inhibitors based on a benzoic acid scaffold and incorporating a neutral P1 ligand.

A series of novel, highly potent, achiral factor Xa inhibitors based on a benzoic acid scaffold and containing a chlorophenethyl moiety directed towards the protease S1 pocket is described. A number of structural features, such as the requirements of the P1, P4 and ester-binding pocket ligands were explored with respect to inhibition of factor Xa. Compound 46 was found to be the most potent compound in a series of antithrombotic secondary assays.

Wilms' tumor--single-center experience with renal surgery.

OBJECTIVE: To analyze the perioperative complications of renal surgery in a sample of patients with Wilms' tumor (WT), especially with regard to the effects of preoperative chemotherapy. MATERIAL AND METHODS: The case histories of 34 patients (mean age 4 years) who underwent renal surgery for suspicion of WT between 1989 and 2002 were retrospectively analyzed with special regard to intra- or postoperative complications. In total, 32 patients had undergone a radical nephrectomy and two had undergone organ-sparing renal surgery because of bilateral involvement. The median maximal tumor diameter was 9.6 cm. In 10 patients preoperative chemotherapy was completely renounced or had to be stopped early. All other patients were treated according to the protocols of the Société Internationale d'Oncologie Pédiatrique (SIOP)-9 or 93/01 studies. RESULTS: A total of 5/34 patients (14.7%) had perioperative complications. There was one intraoperative tumor rupture in a patient who had undergone an emergency radical nephrectomy before completing preoperative chemotherapy. Furthermore, three patients had to be reoperated on because of small bowel obstruction during the first 12 months after renal surgery. Another patient developed pancreatitis postoperatively due to delayed drainage of pancreatic secretion. These four patients had completed preoperative chemotherapy. All postoperative complications occurred in patients with tumors > 10 cm in diameter or after extended surgery for vascular or extrarenal tumor involvement. CONCLUSIONS: The presented incidence of surgical complications associated with the operative treatment of WT is most probably due to the local extent of the primary tumor leading to more extensive surgical intervention. It remains unclear whether the extent of preoperative chemotherapy influences the complication rate.

Treatment of iatrogenic postoperative ureteral strictures with Acucise endoureterotomy.

OBJECTIVES: To determine factors influencing the outcome of Acucise endoureterotomy in patients with iatrogenic postoperative ureteral strictures after different open surgical procedures. MATERIAL AND METHODS: Acucise endoureterotomy was performed in 18 patients with ureteral strictures after pyeloplasty (n = 5), renal transplantation (n = 5), ureteroenteric anastomosis (n = 3), calicoureterostomy (n = 1), ureterocystoneostomy (n = 1), hysterectomy (n = 1), ureterorenoscopy (n = 1) and transurethral resection of the ureteral orifice (n = 1). Success was determined as relief of clinical symptoms, improvement of renal function or improvement of radiographic findings. RESULTS: The overall success rate was 61% (mean follow-up: 21.5 months). Six out of 18 patients showed relevant side effects. Neither the localization of the stricture nor the duration of postoperative ureteral stenting but the length of the stricture had influence on the postoperative outcome. Decreased renal function to less than 25% of the total function was always associated with failure of the treatment. The time period between the ureteral injury and the appearance of the ureteral stricture had influence on the outcome of the treatment. CONCLUSIONS: Acucise endoureterotomy is effective in the treatment of postoperative ureteral strictures, but only in selected cases. The selection criteria are the time period from the primary operation to the appearance of the stricture (>6 months), the length of the stricture (<1.5 cm) and the renal function (>25% of the total function). In other cases, open surgical treatment of the ureteral stricture may provide better results.