ascorbic-acid and betulin

Oxidative stress plays an important role in cellular processes. Consequently, oxidative stress also affects etiology, progression, and response to therapeutics in various pathological conditions including malignant tumors. Oxidative stress and associated outcomes are often brought about by excessive generation of reactive oxygen species (ROS). Accumulation of ROS occurs due to dysregulation of homeostasis in an otherwise strictly controlled physiological condition. In fact, intracellular ROS levels are closely associated with the pathological status and outcome of numerous diseases. Notably, mitochondria are recognized as the critical regulator and primary source of ROS. Damage to mitochondria increases mitochondrial ROS (mROS) production, which leads to an increased level of total intracellular ROS. However, intracellular ROS level may not always reflect mROS levels, as ROS is not only produced by mitochondria but also by other organelles such as endoplasmic reticulum and peroxisomes. Thus, an evaluation of mROS would help us to recognize the biological and pathological characteristics and predictive markers of malignant tumors and develop efficient treatment strategies. In this review, we describe the pathological significance of mROS in malignant neoplasms. In particular, we show the association of mROS-related signaling in the molecular mechanisms of chemically synthesized and natural chemotherapeutic agents and photodynamic therapy.

Topics: Amaryllidaceae Alkaloids; Animals; Antineoplastic Agents; Antioxidants; Ascorbic Acid; Biological Products; Cell Line, Tumor; Curcumin; Endoplasmic Reticulum; Homeostasis; Humans; Isoquinolines; Mitochondria; Oxidative Stress; Paclitaxel; Peroxisomes; Photochemotherapy; Photosensitizing Agents; Reactive Oxygen Species; Signal Transduction; Tannins; Taxoids; TNF-Related Apoptosis-Inducing Ligand; Triterpenes

The current study targets the chemical constituents of Caesalpinia decapetala (Roth) Alston and investigates the bioactivities of the isolated compounds. Fourteen known compounds were isolated using column chromatography, and structural identification was performed by physical and spectral analyses. The biological activities of the compounds were also evaluated by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2,2-diphenlyl-1-picrylhydrazyl (DPPH) assays. Emodin (6), baicalein (9), and apigenin (12) displayed antitumor activities against the MGC-803 cell line, while quercetin (2), rutin (5), baicalein (9), and epicatechin (13) showed stronger DPPH scavenging activities compared with ascorbic acid. Andrographolide (1), quercetin (2), bergenin (4), rutin (5), emodin (6), betulin (7), baicalein (9), polydatin (10), salicin (11), and apigenin (12), were obtained from C. decapetala (Roth) Alston for the first time.

Topics: Antineoplastic Agents; Antineoplastic Agents, Phytogenic; Ascorbic Acid; Benzopyrans; Benzyl Alcohols; Biphenyl Compounds; Caesalpinia; Cell Line, Tumor; Cell Survival; Emodin; Flavonoids; Free Radical Scavengers; Free Radicals; Glucosides; Humans; Inhibitory Concentration 50; Molecular Structure; Picrates; Plant Extracts; Stilbenes; Triterpenes