PIASA, A Novel Peptide, Prevents SH-SY5Y Neuroblastoma Cells against Rotenone-induced Toxicity.

BACKGROUND AND OBJECTIVE: This investigation explores the neuroprotective effect of PIASA, a newly designed peptide, VCSVY, in in-silico and in opposition to rotenone stimulated oxidative stress, mitochondrial dysfunction, and apoptosis in an SH-SY5Y cellular model. METHODS: Docking and visualization of the PIASA and rotenone were progressed against mitochondrial respiratory complex I (MCI). The in-silico analysis showed PIASA to have interaction with the binding sites of rotenone, which may reduce the rotenone interaction and its toxicity too. The SH-SY5Y cells were segregated into four experimental groups: Group I: untreated control cells; Group II: rotenone-only (100 nM) treated cells; Group III: PIASA (5 µM) + rotenone (100 nM) treated cells; and Group IV: PIASA-only (5 µM) treated cells. RESULTS: We evaluated the cell viability, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), apoptosis (dual staining technique), nuclear morphological changes (Hoechst staining technique), the expressions of BAX, Bcl-2, cyt c, pro-caspase 3, and caspase 3, -6, -8, -9, and cleaved caspase 3 by western blot analysis. In SH-SY5Y cells, we further observed the cytotoxicity, oxidative stress and mitochondrial dysfunction in rotenone-only treated cells, whereas pretreatment of PIASA attenuated the rotenone-mediated toxicity. Moreover, rotenone toxicity is caused by complex I inhibition, which leads to mitochondrial dysfunction, increased BAX expression, while downregulating the Bcl-2 expression and cyt c release, and then finally, caspases activation. PIASA pretreatment prevented the cytotoxic effects via the normalization of apoptotic marker expressions influenced by rotenone. In addition, pre-clinical studies are acceptable in rodents to make use of PIASA as a revitalizing remedial agent, especially for PD in the future. CONCLUSION: Collectively, our results propose that PIASA mitigated rotenone-stimulated oxidative stress, mitochondrial dysfunction, and apoptosis in rotenone-induced SH-SY5Y cells.

Isolongifolene mitigates rotenone-induced dopamine depletion and motor deficits through anti-oxidative and anti-apoptotic effects in a rat model of Parkinson's disease.

Isolongifolene (ILF), a novel tricyclic sesquiterpene compound isolated from the Indian herb Murraya koenigii (M. koenigii), has been previously demonstrated to have a neuroprotective effect against rotenone-induced oxidative stress, mitochondrial dysfunction, and apoptosis in in vitro model. However, these neuroprotective and anti-apoptotic effects of ILF are not well understood and must be further investigated to elucidate the underlying molecular mechanism of ILF in animal experiments. The objective of this study was to evaluate the neuroprotective effect of ILF on motor impediments, neurochemical variables, anti-oxidative indices, and apoptotic protein expression in a rotenone-induced rat model of Parkinson's disease (PD). PD was induced in male albino Wistar rats via injection of 2.5 mg/kg rotenone for 4 weeks. Rotenone produces PD-like effects by promoting mitochondrial complex I inhibition and microglial activation properties. The protective effect of three different doses of ILF 5, 10 and 20 mg/kg were evaluated for spontaneous locomotion, rotarod performance, and striatal dopamine (DA) content. The results showed that ILF dose-dependently ameliorated the rotenone-induced striatal DA loss and motor impairment from 10 mg/kg. Therefore, we selected 10 mg/kg as the ILF dose for further investigation. Chronic administration of rotenone caused PD-related pathological processes like oxidative stress, and produced a significant decrease in tyrosine hydroxylase (TH), DA transporter (DAT), Vesicular monoamine transporter 2 (VMAT2), and a significant upregulated in α-synuclein and apoptotic protein expression of Bax, Cyt-C and caspases -3, -8 and -9 as well as by decreasing Bcl2 expression. Treatment with ILF 10 mg/kg mitigated oxidative stress in rotenone-treated rats. Furthermore, ILF dramatically alleviated rotenone-induced toxicity and cell death by increasing TH, DAT and VMAT2 expression and reducing the upregulation of α-synuclein, Bax, Cyt-C, caspases -3, -8 and -9. Together, our results confirm that ILF's protective effect against rotenone-induced PD is mediated through anti-oxidant and anti-apoptotic properties. However, further in-depth investigations on ILF's anti-inflammatory and mitochondrial protective abilities are needed to establish ILF as a potential drug candidate for the treatment of Parkinson's disease.

DHF-BAHPC molecule exerts ameliorative antioxidant status and reduced cadmium-induced toxicity in zebrafish (Danio rerio) embryos.

In this study, we report the antioxidant and antitoxic potential of chemically synthesized 4-oxo-2-phenyl-4H-chromene-7,8-diyl bis((1-amino-2-hydroxypropyl)carbamate) (DHF-BAHPC) compound using in vitro and in vivo assays. The DHF-BAHPC was synthesized by linking 7,8-Dihydroxyflavone (DHF) with two molecules of Fmoc-threonine and characterized by Ultraviolet-visible spectroscopy (UV-vis), Fourier-transform infrared spectroscopy (FT-IR), 1H NMR, 13C NMR and Mass spectrometry (MS). In vitro, antioxidant assay results revealed that DHF-BAHPC has a dose-dependent radical scavenging potential towards DPPH, ABTS, FRAP and H2O2 radicals with an IC50 range of 15.45, 66.27, 25.71, 4.375 µg/mL, respectively. Furthermore DHF-BAHPC treatment significantly altered cadmium (Cd) intoxicated zebrafish embryos by rescuing the developmental changes associated with severe histological and reduced the level of defensive antioxidant activities (SOD, CAT, GPx and GST). The overall results of the present study represented that DHF-BAHPC may be used as a potential drug in redox-based therapeutics.

Author Correction: Design and Molecular dynamic Investigations of 7,8-Dihydroxyflavone Derivatives as Potential Neuroprotective Agents Against Alpha-synuclein.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Design and Molecular dynamic Investigations of 7,8-Dihydroxyflavone Derivatives as Potential Neuroprotective Agents Against Alpha-synuclein.

Parkinson's disease (PD) is the second most common neurodegenerative disorder caused due to loss of dopaminergic neurons in substantia nigra pars compacta, which occurs the presence of Lewy bodies made up of Alpha-synuclein (ASN) aggregation resulting in neuronal death. This study aims to identify potent 7,8-Dihydroxyflavone (DHF) derivatives to inhibit the ASN aggregation from in silico analysis. Molecular docking study reveals that carbamic ester derivatives of DHF [DHF-BAHPC (8q), DHF-BAHPEC (8s), DHF-BAHEC (8p), DHF-BDOPC (8c), DHF-BAPEC (8n) and DHF-BAMC (8h)] have good binding affinity towards ASN, when compared with DHF and L-DOPA; their docking score values are -16.3120, -16.1875, -15.2223, -14.3118, -14.2893, -14.2810, -14.0383, and -9.1560 kcal/mol respectively. The in silico pharmacological evaluation shows that these molecules exhibit the drug-likeness and ADMET properties. Molecular dynamics simulation confirms the stability of the molecules with ASN. The intermolecular interaction analyzed under the dynamic condition, allows to identify the candidate which potentially inhibits ASN aggregation. Hence, we propose that DHF derivatives are the potential lead drug molecules and preclinical studies are needed to confirm the promising therapeutic ability against PD.

Isolongifolene attenuates rotenone-induced mitochondrial dysfunction, oxidative stress and apoptosis.

The present study was carried out to investigate the neuroprotective effects of isolongifolene (ILF), a tricyclic sesquiterpene of Murraya koenigii, against rotenone-induced mitochondrial dysfunction, oxidative stress and apoptosis in a cellular model. SH-SY5Y human neuroblastoma cells were divided into four experimental groups (control, rotenone (100 nM), ILF (10 microM) + rotenone (100 nanoM), ILF 10 microM alone treated) based on 3-(4, 5-dimethyl 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results of the present study showed that the ILF treatment significantly alleviated rotenone-induced cytotoxicity, oxidative stress and mitochondrial dysfunction in SH-SY5Y cells. Moreover, ILF attenuated rotenone induced toxicity by down-regulating  Bax, caspases-3, 6, 8 and 9 expression and up-regulating of Bcl-2 expression. Furthermore regulation of p-P13K, p-AKT and p-GSK-3 beta expression by ILF, clearly confirmed its protective effects. Taken together, our results suggested that ILF attenuated rotenone-induced oxidative stress, mitochondrial dysfunction and apoptosis through the regulation of P13K/AKT/GSK-3 beta signaling pathways. However further pre-clinical studies are warranted in rodents to use ILF as a promising therapeutic agent for PD in future.