Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive death of cortical and spinal motor neurons, for which there is no effective treatment. Using a cell-based assay for compounds capable of preventing motor neuron cell death in vitro, a collection of approximately 40,000 low-molecular-weight compounds was screened to identify potential small-molecule therapeutics. We report the identification of cholest-4-en-3-one, oxime (TRO19622) as a potential drug candidate for the treatment of ALS. In vitro, TRO19622 promoted motor neuron survival in the absence of trophic support in a dose-dependent manner. In vivo, TRO19622 rescued motor neurons from axotomy-induced cell death in neonatal rats and promoted nerve regeneration following sciatic nerve crush in mice. In SOD1G93A transgenic mice, a model of familial ALS, TRO19622 treatment improved motor performance, delayed the onset of the clinical disease, and extended survival. TRO19622 bound directly to two components of the mitochondrial permeability transition pore: the voltage-dependent anion channel and the translocator protein 18 kDa (or peripheral benzodiazepine receptor), suggesting a potential mechanism for its neuroprotective activity. TRO19622 may have therapeutic potential for ALS and other motor neuron and neurodegenerative diseases.Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder that selectively affects motor neurons in the spinal cord, brainstem, and cortex. ALS affects people of all races and ethnic backgrounds with an incidence approximately 2 per 100,000 individuals (McGuire and Nelson, 2006). The onset of ALS is most common in the 55 to 75 year age range, and incidence rises with advancing age; men have a higher risk of developing the disease than women (Nelson, 1995). Common clinical features of ALS include muscle weakness and fasciculations. These occur predominantly in limbs, although bulbar onset pathology can also lead to tongue atrophy and dysphagia. Failure of the respiratory muscles and cardiac complications are generally the fatal event, occurring within an average of 3 years of disease onset, with only a 5% chance of survival 5 years after diagnosis (del Aguila et al., 2003). Although 5 to 10% of ALS This work was supported by the Association Française contre les Myopathies.1 Current affiliation: Center for Motor Neuron Biology and Disease, Columbia University, New York.Article, publication date, and citation information can be found at

The widespread neuropeptide vasoactive intestinal peptide (VIP) has two receptors VPAC 1 and VPAC 2 . Solid-phase syntheses of VIP analogs in which each amino acid has been changed to alanine (Ala scan) or glycine was achieved and each analog was tested for: (i) threedimensional structure by ab initio molecular modeling; (ii) ability to inhibit 125 ]VIP analog which constitutes the first highly selective (>1,000-fold) human VPAC 1 receptor agonist derived from VIP ever described. The vasoactive intestinal peptide (VIP)1 is a prominent neuropeptide with wide distribution in both peripheral and central nervous systems and a large spectrum of biological actions in mammals (1, 2). VIP-containing nerves and VIP effects have been described in digestive tract, cardiovascular system, airways, reproductive system, immune system, endocrine glands, and brain (1). Besides its short-term actions on exocrine secretions, hormone release, muscle relaxation, and metabolism (1, 2), VIP has been also characterized as a growth regulator for fetuses and tumor cells and during embryonic brain development (3). There are recent evidences for an important role of VIP in the perception of pain (4) and suppression of inflammation (5). Finally, VIP has been involved in diseases such as the watery diarrhea syndrome and clinical applications of VIP have been already suggested in impotence, asthma, lung injury, a variety of tumors and neurodegenerative diseases (1-3).VIP belongs to a large family of structurally related peptides (2, 6, 7) that comprises VIP, pituitary adenylate cyclase-activating peptide PACAP-27, and its C-terminal extended form PACAP-38, secretin, glucagon, and glucagon-like peptides-1 and -2, gastric inhibitory polypeptide, peptide histidine methionine amide, growth hormone-releasing factor (GRF), and peptides isolated from the venom of the Gila Monster. VIP and PACAP are the most closely related peptides in terms of structure and function (2, 6). They share two common receptors, VPAC 1 and VPAC 2 , which display high affinity for both VIP and PACAP (2,8). These receptors together with receptors for VIP-related peptides (see above) clearly constitute an original subfamily within the superfamily of G protein-coupled receptors (2, 9, 10). This subfamily referred to as class II (2) also comprises receptors for parathyroid hormone, calcitonin, corticotropin-releasing factor, and the so called EGF-TM7 receptors (11). Class II family of receptors for peptides display several common properties including large N-terminal extracellular domains containing highly conserved cystein residues, N-terminal leader sequences, and complex gene organization with many introns (2).Although the structure-function relationship of VIP receptors, including VPAC 1 and VPAC 2 , has been recently documented (2,9,(12)(13)(14)(15)(16)(17)(18)(19)(20), the structure-function relationship of VIP itself is still poorly understood. Some old studies carried out before the characterization and cloning of VIP receptor subtypes (21-23) indicated that: (i) th...

3,5-Seco-4-nor-cholestan-5-one oxime-3-ol (TRO40303) is a new cardioprotective compound coming from a chemical series identified initially for neuroprotective properties. TRO40303 binds specifically to the mitochondrial translocator protein 18 kDa (TSPO) at the cholesterol site. After intravenous administration, TRO40303 tissue distribution was comparable to that of TSPO, and, in particular, the drug accumulated rapidly in the heart. In a model of 35 min of myocardial ischemia/24 h of reperfusion in rats, TRO40303 (2.5 mg/kg) reduced infarct size by 38% (p Ͻ 0.01 versus control), when administered 10 min before reperfusion, which was correlated with reduced release of apoptosis-inducing factor from mitochondria to the cytoplasm in the ischemic area at risk. Although TRO40303 had no effect on the calcium retention capacity of isolated mitochondria, unlike cyclosporine A, the drug delayed mitochondrial permeability transition pore (mPTP) opening and cell death in isolated adult rat cardiomyocytes subjected to 2 h of hypoxia followed by 2 h of reoxygenation and inhibited mPTP opening in neonatal rat cardiomyocytes treated with hydrogen peroxide. The effects of TRO40303 on mPTP in cell models of oxidative stress are correlated with a significant reduction in reactive oxygen species production and subsequent calcium overload. TRO40303 is a new mitochondrial-targeted drug and inhibits mPTP triggered by oxidative stress. Its mode of action differs from that of other mPTP inhibitors such as cyclosporine A, thus providing a new pharmacological approach to study mPTP regulation. Its efficacy in an animal model of myocardial infarctions makes TRO40303 a promising new drug for the reduction of cardiac ischemia-reperfusion injury.

Hepatocellular carcinoma is the most frequent primary liver cancer. Macroautophagy/autophagy inhibitors have been extensively studied in cancer but, to date, none has reached efficacy in clinical trials. In this study, we demonstrated that GNS561, a new autophagy inhibitor, whose anticancer activity was previously linked to lysosomal cell death, displayed high liver tropism and potent antitumor activity against a panel of human cancer cell lines and in two hepatocellular carcinoma in vivo models. We showed that due to its lysosomotropic properties, GNS561 could reach and specifically inhibited its enzyme target, PPT1 (palmitoyl-protein thioesterase 1), resulting in lysosomal unbound Zn 2+ accumulation, impairment of cathepsin activity, blockage of autophagic flux, altered location of MTOR (mechanistic target of rapamycin kinase), lysosomal membrane permeabilization, caspase activation and cell death. Accordingly, GNS561, for which a global phase 1b clinical trial in liver cancers was just successfully achieved, represents a promising new drug candidate and a hopeful therapeutic strategy in cancer treatment. Abbreviations : ANXA5:annexin A5; ATCC: American type culture collection; BafA1: bafilomycin A 1 ; BSA: bovine serum albumin; CASP3: caspase 3; CASP7: caspase 7; CASP8: caspase 8; CCND1: cyclin D1; CTSB: cathepsin B; CTSD: cathepsin D; CTSL: cathepsin L; CQ: chloroquine; iCCA: intrahepatic cholangiocarcinoma; DEN: diethylnitrosamine; DMEM: Dulbelcco’s modified Eagle medium; FBS: fetal bovine serum; FITC: fluorescein isothiocyanate; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HCC: hepatocellular carcinoma; HCQ: hydroxychloroquine; HDSF: hexadecylsulfonylfluoride; IC 50 : mean half-maximal inhibitory concentration; LAMP: lysosomal associated membrane protein; LC3-II: phosphatidylethanolamine-conjugated form of MAP1LC3; LMP: lysosomal membrane permeabilization; MALDI: matrix assisted laser desorption ionization; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MKI67: marker of proliferation Ki-67; MTOR: mechanistic target of rapamycin kinase; MRI: magnetic resonance imaging; NH 4 Cl: ammonium chloride; NtBuHA: N-tert-butylhydroxylamine; PARP: poly(ADP-ribose) polymerase; PBS: phosphate-buffered saline; PPT1: palmitoyl-protein thioesterase 1; SD: standard deviation; SEM: standard error mean; vs, versus; Zn 2+ : zinc ion; Z-Phe: Z-Phe-Tyt(tBu)-diazomethylketone; Z-VAD-FMK: carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone.