RESUMEN
The influence of various risk factors such as aging, intricate cellular molecular processes, and lifestyle factors like smoking, alcohol consumption, caffeine intake, and occupational factors has received increased focus in relation to the risk and development of Parkinson's disease (PD). Limited research has been conducted on the assessment of lifestyle impact on kynurenine 3-monooxygenase (KMO) gene in PD. A total of 164 subjects, including 82 PD cases and 82 healthy individuals, were recruited based on specific inclusion and exclusion criteria. The severity of PD and clinical assessment were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr (HY) scaling. Sanger sequencing was performed to analyse the KMO gene in the recruited subjects, and case-control studies were conducted. The UPDRS assessment revealed significant impairments in smell, tremors, walking, and posture instability in the late-onset PD cohorts. The HY scaling indicated a higher proportion of late-onset cohorts in stage 2. Moreover, both alcoholic and non-alcoholic groups showed significantly increased levels of 3-HK in late-onset PD. Gene analysis identified missense variants at position g.241593373 T > A (rs752312199) and intronic variants at positions g.241592623A > G (rs640718), g.241592800C > A (rs990388262), g.241592802A > C (rs1350160268), g.241592808 T > C (rs1478255936), and g.241592812G > T (rs948928931). The alterations in the KMO gene were found to influence the levels of kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK). Genomic analysis revealed a high prevalence of missense mutations in the late-onset PD groups, leading to a decline in 3-HK levels in patients. This leads to the reduction of the progression of disease in late-onset groups which shows that this mutation may lead to the protective effect on the PD subjects. This study suggests the use of KYNA and 3-HK as potential biomarkers in analysing the progression of disease. This study is limited by its small sample size. To overcome this limitation, a larger study involving in greater number of participants is needed to thoroughly investigate the KMO gene and KP metabolites, to enhance our understanding of Parkinson's disease progression, and to enhance diagnostic capabilities.
RESUMEN
Cu/Zn superoxide dismutase (SOD1) mutations are associated to the motor neuron disorder, amyotrophic lateral sclerosis (ALS), which is characterized by aggregates of the misfolded proteins. The distribution of mutations all over the three-dimensional structure of SOD1 makes it complex to determine the exact molecular mechanism underlying SOD1 destabilization and the associated ALS pathology. In this study, we have examined structure and dynamics of SOD1 protein upon two ALS associated point mutations at the surface residue Glu100 (E100G and E100K), which is located far from the Cu and Zn sites and dimer interface. The molecular dynamics simulations were performed for these mutants for 50ns using GROMACS package. Our results indicate that the mutations result in structural destabilization by affecting the gate keeping role of Glu100 and loss of electrostatic interactions on the protein surface which stabilizes the ß-barrel structure of the native form. Further, these mutations could increase the fluctuations in the zinc-binding loop (loop IV), primarily due to loss of hydrogen bond between Asp101 and Arg79. The relaxed conformation of Arg79 further affects the native conformation of His80 and Asp83, that results in altered zinc site geometry and the structure of the substrate channel. Our results clearly suggest that, similar to the mutations located at metal sites/dimer interface/disulfide regions, the mutations at the far positioned site (Glu100) also induce significant conformational changes that could affect the metallation and structure of SOD1 molecule, resulting in formation of toxic intermediate species that cause ALS.
Asunto(s)
Esclerosis Amiotrófica Lateral , Esclerosis Amiotrófica Lateral/genética , Sitios de Unión , Humanos , Simulación de Dinámica Molecular , Mutación , Pliegue de Proteína , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1/genética , ZincRESUMEN
Endocan known as a cardiovascular inflammatory biomarker, found to be elevated in atherosclerosis. However, the 3D structure and the stimulatory effect of endocan on macrophages are unknown. Hence, we predicted the three-dimensional structure of human endocan and calculated the binding efficiency of statins towards endocan and determined their inhibition potential. Molecular docking studies of simvastatin (-9.64 kcal/mol) showed that binding is stabilized by the hydrogen bonds with Cys60, Cys54 residues, and several hydrophobic interactions. Moreover, MD simulations and pull-down assay results confirmed that simvastatin binding is stable with human endocan. In-silico results obtained in the present study were validated under in-vitro condition by analysing the effect of endocan under simvastatin treatment. Western blot results have shown that simvastatin could reduce endocan expression in LPS-treated endothelial cells. Further, endocan treatment in RAW 264.7 macrophages stimulates NO, ROS production and increases iNOS, CRP expression. However, endocan and simvastatin combination treatment could suppress NO, ROS production and iNOS, CRP activation. The present study results suggest that endocan could induce vascular inflammation in macrophages. In addition, the results showed that simvastatin could interact with endocan and thereby suppress the stimuli-induced effect. Thus, endocan may play a role in atherogenesis by activating macrophages.