A good correlation between HSP70 and the suppression of polyQ damage (Figure3C-3D) suggests that AZD reduced polyQ toxicity through induction of chaperones. sequence with higher affinity. These unique findings qualify AZD as an ideal lead molecule for consideration for drug development against NDs that affect millions worldwide. Keywords: heat shock factor 1, HSF1, neurodegenerative diseases, small molecule, azadiradione, Gerotarget == INTRODUCTION == Neurodegenerative diseases (NDs) like polyglutamine (polyQ) based diseases which include spinal and bulbar muscular atrophy (SBMA), dentato-rubral-pallidoluysian atrophy (DRPLA), Machado-Joseph disease MJD/SCA3), several spinocerebellar ataxias (SCA), and Huntington’s, Parkinson’s- and Alzheimer’s diseases affect millions of people worldwide [1, 2]. People affected with these diseases survive in a debilitated condition, which imposes a heavy financial and psychological burden on the society. Till date, there is no definitive cure as the current treatment options offer only disease-specific management strategies such as neuroleptic and antipsychotic drugs for temporary relief of disease symptoms [3, 4]. Accumulation of non-native protein aggregates, defective cellular heat shock response (HSR) and compromised protein quality control pathways are common hallmarks of various NDs [58]. In normal cells heat shock factor 1 (HSF1), the central regulator of HSR, is sequestered in the cytoplasm in a repressive complex assembled with HSP90, p23, immunophilin, HSP70, and HSP40 [912]. Exposure to elevated temperature or a proteotoxic stress results in the disassembly of this repressive complex so that the released monomeric HSF1 molecules assemble into DNA binding competent homotrimer form. HSF1 as a homotrimer binds to the recognition element HSE (repetitive 5-nGAAn-3) on its ODM-201 target chaperone genes to activate their expression which helps in refolding of mis- or unfolded proteins or removal of the non-native protein aggregates [13]. Involvement of ribonucleoprotein complexes in the trimerization and activation of HSF1 has been demonstrated ODM-201 [14, 15]. Chemical inhibition of HSP90 and proteasome also results in HSF1 activation [12, 16]. Forced upregulation of HSF1 and or its target genes such as HSP70 was shown to reduce protein aggregate accumulation, associated toxicity, and diseases symptoms in C. elegans and mouse models of Huntington’s disease [5, 6, 17]. As expected HSF1 downregulation was also associated with enhanced polyglutamine-induced toxicity [18]. Several small molecule activators of HSF1 obtained through screening of small molecule libraries and natural products, have been reported and are in various developmental stages of drug development [3, 19]. Nevertheless, given the severity of disease burden on the patients and the society, compounds ODM-201 with novel and unique functional mechanisms are desired in the repertoire ODM-201 to explore better treatment options. A small molecule with a unique mode of action is also desired to obtain deeper insights into BPTP3 the molecular mechanisms of function of HSF1. We report here azadiradione (AZD) as an inducer of HSF1 activity. We obtained AZD through screening of methanolic extract ofAzadirachta indicaseeds by cell-based reporter activity assay coupled purification approach. Azadirachta indica, locally known as Neem, has been in use in the traditional medicine for treatment of many diseases because of its anti-inflammatory, anti-anxiety activities, and for enhancement of cognitive ability [20, 21]. We show here that treatment with AZD efficiently ameliorates polyglutamine (polyQ) protein induced toxicity in the cellular and fruit fly models. The ameliorating effects were correlated with AZD induced upregulation of heat shock protein chaperone (HSP) expression mediated by direct interaction with HSF1 protein. == RESULTS == == Identification and purification of azadiradione from neem seeds as an activator of HSF1 by cell based reporter assays == Screening for activator of HSF1 was carried out using cell-based reporter system harboring renilla luciferase (Rluc) and GFP independently under the control of ODM-201 six tandem copies of HSE (6xHSE). The.