s-allylcysteine and astaxanthine

Neuroprotective effect of astaxanthin-s-allyl cysteine diester (AST-SAC) against high glucose (HG)-induced oxidative stress in in vitro and cognitive decline under diabetes conditions in in vivo has been explored. Pretreatment of AST-SAC (5, 10 and 15 μM) dose-dependently preserved the neuronal cells (SH-SY5Y) viability against HG toxicity through i) decreasing oxidative stress (decreasing reactive oxygen species generation and increasing endogenous antioxidants level); ii) protecting mitochondrial function [oxidative phosphorylation (OXPHOS) complexes activity and mitochondrial membrane potential (MMP)]; and iii) decreasing p53 level thereby subsequently decreasing the level of apoptotic marker proteins. Male Spraque-Dawley rats were orally administered AST-SAC (1 mg/kg/day) for 45 days in streptozotocin-induced diabetes mellitus (DM) rats. AST-SAC administration prevented the loss of spatial memory in DM rats as determined using the novel object location test. AST-SAC administration alleviated the DM-induced injury in brain such as increased cholinesterases activity, elevated oxidative stress and mitochondrial dysfunction. Altogether, the results from the present study demonstrated that AST-SAC averted the neuronal apoptosis and preserved the cognitive function against HG toxicity under DM conditions.

Topics: Animals; Cell Line, Tumor; Cell Survival; Cognitive Dysfunction; Cysteine; Diabetes Mellitus, Experimental; Dose-Response Relationship, Drug; Glucose; Humans; Male; Mitochondria; Neurons; Oxidative Stress; Rats; Rats, Sprague-Dawley; Tumor Suppressor Protein p53; Xanthophylls

In Alzheimer's disease (AD) and diabetes-associated cognitive decline, the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity is increased. AChE exists as different globular molecular forms: tetramer (G4), dimer (G2) and monomer (G1). In adult brain, G4 form is abundant however in AD, the ratio of lower molecular forms (G1) to G4 form increased. Hence, the present study delineated the inhibition of novel astaxanthin-s-allyl cysteine (AST-SAC) against BChE and various molecular forms of AChE. Cobra venom, human erythrocyte and Electrophorus electricus was used as source of G1, G2 and G4 form of AChE. AST-SAC showed inhibition against G1 (IC

Topics: Acetylcholinesterase; Animals; Brain; Butyrylcholinesterase; Cholinesterase Inhibitors; Computer Simulation; Cysteine; Humans; Molecular Dynamics Simulation; Xanthophylls

In humans, alpha-glucosidase activity is present in sucrase-isomaltase (SI) and maltase-glucoamylase (MGAM). α-glucosidase is involved in the hydrolyses of disaccharide into monosaccharides and results in hyperglycemia. Subsequently chronic hyperglycemia induces oxidative stress and ultimately leads to the secondary complications of diabetes. Hence, identifying compounds with dual beneficial activity such as efficient antioxidant and α-glucosidase inhibition property has attracted the attention in recent years. Keeping these views, in the present study astaxanthin (AST; a natural antioxidant present in marine microalgae) was biconjugated with allyl sulfur amino acid such as s-allyl cysteine (SAC). The synthesized AST-SAC (with molecular weight of 883.28) was characterized using UV-visible spectrophotometer, ESI-MS, and NMR analysis. AST-SAC showed potent antioxidant property in vitro. AST-SAC inhibited Saccharomyces cerevisiae α-glucosidase (IC

Topics: alpha-Glucosidases; Animals; Antioxidants; Catalytic Domain; Computer Simulation; Cysteine; Humans; Kinetics; Microalgae; Molecular Docking Simulation; Rats; Saccharomyces cerevisiae; Xanthophylls