Nootchanat Mairuae

Bio: Nootchanat Mairuae is an academic researcher from Mahasarakham University. The author has contributed to research in topics: Oxidative stress & Programmed cell death. The author has an hindex of 7, co-authored 12 publications receiving 124 citations. Previous affiliations of Nootchanat Mairuae include Chulalongkorn University.

Cytotoxic and antimigratory effects of Cratoxy formosum extract against HepG2 liver cancer cells.

Abstract: The aim of the present study was to investigate the molecular mechanisms underlying Cratoxylum formosum (CF) Dyer-induced cancer cell death and antimigratory effects in HepG2 liver cancer cells. The cytotoxic, antiproliferative and antimigratory effects of CF leaf extract on human liver cancer HepG2 cell lines were evaluated using sulforhodamine B, colony formation, and wound healing assays. In addition, apoptosis induction mechanisms were investigated via reactive oxygen species (ROS) formation, caspase 3 activities, and mitochondrial membrane potential (ΔΨm) disruption. Gene expression and apoptosis-associated protein levels were measured by reverse transcription-quantitative polymerase chain reaction and western blotting. CF induced HepG2 cell death in a time- and dose-dependent manner with half maximal inhibitory concentration values of 219.03±9.96 and 124.90±6.86 µg/ml at 24 and 48 h, respectively. Treatment with CF caused a significant and dose-dependent decrease in colony forming ability and cell migration. Furthermore, the present study demonstrated that CF induced ROS formation, increased caspase 3 activities, decreased the ΔΨm, and caused HepG2 apoptosis. CF marginally decreased the expression level of the cell cycle regulatory protein, ras-related C3 botulinum toxin substrate 1 (rho family, small GTP binding protein Rac1) and the downstream protein, cyclin dependent kinase 6. Additionally, CF significantly enhanced p21 levels, reduced cyclin D1 protein levels and triggered cancer cell death. CF leaf extracts induced cell death, stimulated apoptosis and inhibited migration in HepG2 cells. Thus, CF may be useful for developing an anticancer drug candidate for the treatment of liver cancer.

The Role of Reactive Oxygen Species in the Pathogenesis of Alzheimer’s Disease, Parkinson’s Disease, and Huntington’s Disease: A Mini Review

Abstract: Neurodegenerative diseases affect not only the life quality of aging populations, but also their life spans. All forms of neurodegenerative diseases have a massive impact on the elderly. The major threat of these brain diseases includes progressive loss of memory, Alzheimer’s disease (AD), impairments in the movement, Parkinson’s disease (PD), and the inability to walk, talk, and think, Huntington’s disease (HD). Oxidative stress and mitochondrial dysfunction are highlighted as a central feature of brain degenerative diseases. Oxidative stress, a condition that occurs due to imbalance in oxidant and antioxidant status, has been known to play a vital role in the pathophysiology of neurodegenerative diseases including AD, PD, and HD. A large number of studies have utilized oxidative stress biomarkers to investigate the severity of these neurodegenerative diseases and medications are available, but these only treat the symptoms. In traditional medicine, a large number of medicinal plants have been used to treat the symptoms of these neurodegenerative diseases. Extensive studies scientifically validated the beneficial effect of natural products against neurodegenerative diseases using suitable animal models. This short review focuses the role of oxidative stress in the pathogenesis of AD, PD, and HD and the protective efficacy of natural products against these diseases.

Tracking iron in multiple sclerosis: a combined imaging and histopathological study at 7 Tesla

Abstract: Previous authors have shown that the transverse relaxivity R(2)* and frequency shifts that characterize gradient echo signal decay in magnetic resonance imaging are closely associated with the distribution of iron and myelin in the brain's white matter. In multiple sclerosis, iron accumulation in brain tissue may reflect a multiplicity of pathological processes. Hence, iron may have the unique potential to serve as an in vivo magnetic resonance imaging tracer of disease pathology. To investigate the ability of iron in tracking multiple sclerosis-induced pathology by magnetic resonance imaging, we performed qualitative histopathological analysis of white matter lesions and normal-appearing white matter regions with variable appearance on gradient echo magnetic resonance imaging at 7 Tesla. The samples used for this study derive from two patients with multiple sclerosis and one non-multiple sclerosis donor. Magnetic resonance images were acquired using a whole body 7 Tesla magnetic resonance imaging scanner equipped with a 24-channel receive-only array designed for tissue imaging. A 3D multi-gradient echo sequence was obtained and quantitative R(2)* and phase maps were reconstructed. Immunohistochemical stainings for myelin and oligodendrocytes, microglia and macrophages, ferritin and ferritin light polypeptide were performed on 3- to 5-µm thick paraffin sections. Iron was detected with Perl's staining and 3,3'-diaminobenzidine-tetrahydrochloride enhanced Turnbull blue staining. In multiple sclerosis tissue, iron presence invariably matched with an increase in R(2)*. Conversely, R(2)* increase was not always associated with the presence of iron on histochemical staining. We interpret this finding as the effect of embedding, sectioning and staining procedures. These processes likely affected the histopathological analysis results but not the magnetic resonance imaging that was obtained before tissue manipulations. Several cellular sources of iron were identified. These sources included oligodendrocytes in normal-appearing white matter and activated macrophages/microglia at the edges of white matter lesions. Additionally, in white matter lesions, iron precipitation in aggregates typical of microbleeds was shown by the Perl's staining. Our combined imaging and pathological study shows that multi-gradient echo magnetic resonance imaging is a sensitive technique for the identification of iron in the brain tissue of patients with multiple sclerosis. However, magnetic resonance imaging-identified iron does not necessarily reflect pathology and may also be seen in apparently normal tissue. Iron identification by multi-gradient echo magnetic resonance imaging in diseased tissues can shed light on the pathological processes when coupled with topographical information and patient disease history.

Zymography methods for visualizing hydrolytic enzymes

Abstract: Zymography is a technique for studying hydrolytic enzymes on the basis of substrate degradation. It is a powerful, but often misinterpreted, tool yielding information on potential hydrolytic activities, enzyme forms and the locations of active enzymes. In this Review, zymography techniques are compared in terms of advantages, limitations and interpretations. With in gel zymography, enzyme forms are visualized according to their molecular weights. Proteolytic activities are localized in tissue sections with in situ zymography. In vivo zymography can pinpoint proteolytic activity to sites in an intact organism. Future development of novel substrate probes and improvement in detection and imaging methods will increase the applicability of zymography for (reverse) degradomics studies.

Pathogenic implications of iron accumulation in multiple sclerosis

Abstract: Iron, an essential element used for a multitude of biochemical reactions, abnormally accumulates in the central nervous system of patients with multiple sclerosis (MS). The mechanisms of abnormal iron deposition in MS are not fully understood, nor do we know whether these deposits have adverse consequences, i.e., contribute to pathogenesis. With some exceptions, excess levels of iron are represented concomitantly in multiple deep gray matter structures often with bilateral representation, while in white matter pathological iron deposits are usually located at sites of inflammation that are associated with veins. These distinct spatial patterns suggest disparate mechanisms of iron accumulation between these regions. Iron has been postulated to promote disease activity in MS by various means: 1) iron can amplify the activated state of microglia resulting in the increased production of proinflammatory mediators; 2) excess intracellular iron deposits could promote mitochondria dysfunction; and 3) improperly managed iron could catalyze the production of damaging reactive oxygen species. The pathological consequences of abnormal iron deposits may be dependent on the affected brain region and/or accumulation process. Here we review putative mechanisms of enhanced iron uptake in MS and address the likely roles of iron in the pathogenesis of this disease.