Mulibrey Nanism
Dongyou Liu in Handbook of Tumor Syndromes, 2020
Being single-membrane–bound subcellular organelles, peroxisomes participate in numerous metabolic processes (e.g., β-oxidation of long- and very-long-chain fatty acids; biosynthesis of plasmalogens, cholesterol, and bile acid; and the degradation of amino acids and purine). Mutations in genes encoding peroxisomal proteins may result in single peroxisomal enzyme defect as well as defective biogenesis of the peroxisome (i.e., peroxisome biogenesis disorders). Not surprisingly, many clinical features of mulibrey nanism (e.g., prenatal-onset growth failure, facial dysmorphism, hepatomegaly, pigmentary changes in retina, and muscular weakness) are also found in other peroxisome biogenesis disorders, including Zellweger syndrome, neonatal adrenoleukodystrophy, infantile Refsum disease, and rhizomelic chondrodysplasia punctata type 1. However, compared to other peroxisomal disorders, mulibrey nanism tends to have a mild course and does not induce neurological symptoms. The life span of patients with mulibrey nanism is largely influenced by accompanying cardiopathy.
Toxicological Implications of Peroxisome Proliferation
Robert G. Meeks, Steadman D. Harrison, Richard J. Bull in Hepatotoxicology, 2020
Peroxisomes are single membrane-bound cytoplasmic organelles present in a wide variety of cells in both animals and plants including unicellular eukaryotes (Beevers, 1979, Bock et al., 1980;DeDuve, 1983; Tolbert, 1981). These organelles were initially termed “microbodies” by the original discoverer Rhodin (1954), and later on De Duve (1965) coined the term “peroxisome” which reflects the presence in this organelle of enzymes that participate in peroxide-based reactions, i.e., generation of hydrogen peroxide by oxidases and degradation of H2O2 by catalase, the marker enzyme. Peroxisomes in fatty seedlings are called glyoxisomes (Breidenback and Beevers, 1967). Peroxisomes have been shown to contain more than 40 different enzymes, but the enzyme composition of peroxisomes varies depending upon the cell type (Tolbert, 1981). Peroxisomal enzymes participate in many metabolic reactions including respiration, gluconeogenesis, thermogenesis, purine catabolism, fatty acid oxidation, and plasmalogen synthesis (De Duve and Baudhuin, 1967; Hajra and Bishop, 1982; Lazarow, 1988).
Free radicals in biology
Roger L. McMullen in Antioxidants and the Skin, 2018
Similar to lysosomes, peroxisomes are organelles that rid the cell of toxins. Further, peroxisomes contain enzymes, which are capable of transferring hydrogen from selected substrates to oxygen, often resulting in the formation of H2O2—hence, the name peroxisome. Also, peroxisomes are equipped with the enzyme, catalase, which decomposes H2O2 to O2 and H2O. During the process of H2O2 decomposition, catalase also oxidizes other substrates, for example, alcohol, which are considered cellular toxins. In addition to other metabolic processes, a very important role played by peroxisomes is the beta-oxidation of long-chain fatty acids. Throughout the processes described earlier, it is conceivable that H2O2 could easily diffuse through the peroxisome membrane and into the cytoplasm, where it would be likely to encounter either iron or copper, thereby resulting in the Fenton reaction and ultimately leading to the formation of HO•.
Identification and verification of characteristic differentially expressed ferroptosis-related genes in osteosarcoma using bioinformatics analysis
Published in Toxicology Mechanisms and Methods, 2023
Jianhua Hu, Xi Yang, Jing Ren, Shixiao Zhong, Qianbo Fan, Weichao Li
PEX3 encodes a protein (PEX3) participates in the biosynthesis and integrity of peroxisomes and the assembly of membrane vesicles before matrix protein transfer, as well as in functional peroxisome assembly (Farré et al. 2008). Peroxisome biogenesis disorders are a group of genetically heterogeneous autosomal recessive fatal diseases companied by peroxisome dysfunctions and cause Zellweger syndrome (Merkling et al. 2019; Kim et al. 2021). NOX1 encodes a member of the NADPH oxidase family (NOX1), which mediates the catalytic transfer of one electron from oxygen, generating superoxide or hydrogen peroxide (Ogboo et al. 2022). ALOX5 encodes a member of the lipoxygenase gene family (ALOX5) that plays a dual role in inflammatory and allergic processes in the synthesis of leukotrienes from arachidonic acid (Shen et al. 2017). Additionally, ALOX5 is specifically expressed in bone marrow-derived cells. Mutations in the promoter region of ALOX5 suppress the response to the antileukotriene drugs used to treat asthma and may be associated with the pathogenesis of atherosclerosis and several cancers (Leikauf et al. 2013; Rao et al. 2021). The roles of CPEB1, PEX3, and ALOX5 in OS have not been previously reported. However, CPEB1, PEX3, and ALOX5 exert regulatory effects on the occurrence and progression of various types of cancers and are confirmed to be associated with the prognosis of patients with cancer (Sun and Liu 2013; D'Arcangelo et al. 2018; Dou et al. 2019; Wei et al. 2020; Zhou et al. 2020; Tang et al. 2021; Shi et al. 2022).
Physiological and biochemical markers of gamma irradiated white radish (Raphanus sativus)
Published in International Journal of Radiation Biology, 2023
Amina Aly, Noha Eliwa, Ahmed Taha, Zeyad Borik
Peroxidase plays a vital role in plant protection against oxidative stress by scavenging H2O2 in peroxisomes, mitochondria cytosols, as well as chloroplasts of plants cell (Das and Roychoudhury 2014). The present outcomes are in harmony with the data gained by Aly et al. (2019b) and El-Beltagi et al. (2013) who confirmed that gamma-rays amplified peroxidase and polyphenol oxidase enzyme activities and also increasing the number of isozyme bands that could be observed. Similarly, Shen et al. (2010) confirmed that gamma-rays may manipulate the activities and isozymes composition of PODs in soy bean seedlings. Mohamed et al. (2021) found that POD and PPO isozymes analysis of gamma-irradiated plantlets of different potatoes cultivars were more abundant when compared with other un-irradiated cultivars.
Dual transcriptome of Streptococcus mutans and Candida albicans interplay in biofilms
Published in Journal of Oral Microbiology, 2023
Yan Zeng, Elena Rustchenko, Xinyan Huang, Tong Tong Wu, Megan L. Falsetta, Jin Xiao
Most studies have focused on the effect of C. albicans on S. mutans virulence and biofilm formation. Therefore, we also focused on the molecular changes in C. albicans during duo-species interactions. We found that the transcriptomic profile of C. albicans was significantly altered when co-cultured with S. mutans in duo-species biofilms. Compared to C. albicans single species-biofilms, we identified 92 C. albicans DEGs (with over 3-fold Log2 fold change) in the duo-species biofilms. The majority of C. albicans DEGs that related to metabolism pathways were up-regulated, such as ARG3, PXP2, and CAT1. ARG3 is related to arginine biosynthesis. The critical roles of the C. albicans arginine biosynthesis pathway in its cross-kingdom interactions with Actinomyces viscosus in root caries were identified recently, and the study results indicated that targeting this pathway was a practical way to treat root caries caused by multiple species [34]. PXP2 relates to fatty acid degradation and the peroxisome pathway. The peroxisome plays an essential role in eukaryotic cellular metabolism, including beta-oxidation of fatty acids and detoxification of hydrogen peroxide [35]. CAT1 is a catalase-specific inhibitor that can suppress the hyphal growth of wild-type cells, and it is also involved in C. albicans peroxisome, MAPK signaling, and longevity regulating pathways.
Related Knowledge Centers
- Eukaryote
- Hydrogen Peroxide
- Lipid Metabolism
- Reactive Oxygen Species
- Catabolism
- Organelle
- Microbody
- Very Long Chain Fatty Acid
- Branched-Chain Fatty Acid
- D-Amino Acid