ascorbic-acid and gibberellic-acid

Gibberellic acid (GA(3)) is a plant growth regulator used in agriculture worldwide. The present study investigated the propensity of GA(3) to induce hematological disorders. Pregnant Wistar rats were randomly divided into two groups: group I served as controls; group II received orally GA(3) (200 ppm) from the 14th day of pregnancy until day 14 after delivery. GA(3) reduced the number of red blood cells, hemoglobin concentration, and hematocrit in suckling rats, while these parameters remained unchanged in their mothers. White blood cells increased in mothers and were unchanged in their pups. Several studies have associated these hematological disorders with oxidative stress. In fact, GA(3) treatment revealed in erythrocytes a significant increase in malondialdehyde levels and a decrease in antioxidant enzyme activities such as superoxide dismutase, catalase, and glutathione peroxidase. Moreover, a significant decline was observed in acetylcholinesterase activity, glutathione, nonprotein thiols, and vitamin C levels.

Topics: Advanced Oxidation Protein Products; Animals; Animals, Suckling; Antioxidants; Ascorbic Acid; Catalase; Drinking Water; Erythrocytes; Female; Gibberellins; Glutathione; Glutathione Peroxidase; Lipid Peroxidation; Malondialdehyde; Oxidative Stress; Plant Growth Regulators; Pregnancy; Protein Carbonylation; Rats; Rats, Wistar; Superoxide Dismutase

The present study investigates the bone maturity of suckling rats whose mothers were treated with gibberellic acid (GA(3)). Female Wistar rats were divided into two groups: group I that served as controls and group II that received orally GA(3) (200 ppm) from the 14th day of pregnancy until day 14 after delivery. In the GA(3) group, an increase in body and femur weights as well as in femur length of pups was noted when compared to controls. Lipid peroxidation was demonstrated by high femur malondialdehyde levels, while superoxide dismutase, catalase, glutathione peroxidase activities, glutathione and vitamin C levels in femur decreased. GA(3) caused a decrease in calcium and phosphorus levels in bone. The calcium concentration in plasma increased and the phosphorus concentration decreased, while urinary levels of calcium decreased and those of phosphate increased. Moreover, plasma total tartrate-resistant acid phosphatase and total alkaline phosphatase increased. Bone disorders were confirmed by femur histological changes.

Topics: Acid Phosphatase; Animals; Animals, Suckling; Ascorbic Acid; Body Weight; Calcium; Catalase; Environmental Pollutants; Female; Femur; Gibberellins; Glutathione; Glutathione Peroxidase; Glutathione Reductase; Isoenzymes; Lipid Peroxidation; Male; Malondialdehyde; Oxidative Stress; Phosphorus; Pregnancy; Rats; Rats, Wistar; Superoxide Dismutase; Tartrate-Resistant Acid Phosphatase

Cellular redox homeostasis is a hub for signal integration. Interactions between redox metabolism and the ABSCISIC ACID-INSENSITIVE-4 (ABI4) transcription factor were characterized in the Arabidopsis thaliana vitamin c defective1 (vtc1) and vtc2 mutants, which are defective in ascorbic acid synthesis and show a slow growth phenotype together with enhanced abscisic acid (ABA) levels relative to the wild type (Columbia-0). The 75% decrease in the leaf ascorbate pool in the vtc2 mutants was not sufficient to adversely affect GA metabolism. The transcriptome signatures of the abi4, vtc1, and vtc2 mutants showed significant overlap, with a large number of transcription factors or signaling components similarly repressed or induced. Moreover, lincomycin-dependent changes in LIGHT HARVESTING CHLOROPHYLL A/B BINDING PROTEIN 1.1 expression were comparable in these mutants, suggesting overlapping participation in chloroplast to nucleus signaling. The slow growth phenotype of vtc2 was absent in the abi4 vtc2 double mutant, as was the sugar-insensitive phenotype of the abi4 mutant. Octadecanoid derivative-responsive AP2/ERF-domain transcription factor 47 (ORA47) and AP3 (an ABI5 binding factor) transcripts were enhanced in vtc2 but repressed in abi4 vtc2, suggesting that ABI4 and ascorbate modulate growth and defense gene expression through jasmonate signaling. We conclude that low ascorbate triggers ABA- and jasmonate-dependent signaling pathways that together regulate growth through ABI4. Moreover, cellular redox homeostasis exerts a strong influence on sugar-dependent growth regulation.

Topics: Abscisic Acid; Arabidopsis; Arabidopsis Proteins; Ascorbic Acid; Cell Nucleus; Chloroplasts; Cyclopentanes; Gene Expression Regulation, Plant; Gibberellins; Glutathione; Homeostasis; Mutation; Oxidation-Reduction; Oxylipins; Plant Growth Regulators; Signal Transduction; Transcription Factors; Transcriptome