China
Africa
Explore chapters and articles related to this topic
Cytokines and Alveolar Type II Cells
Published in Jason Kelley, Cytokines of the Lung, 2022
The mechanisms by which glucocorticoids affect lung maturation, accumulation of surfactant, and alveolar type II cell surfactant biosynthesis are uncertain. Glucocorticoid receptors are located on type II cells (Ballard et al., 1978b) and, in developing lung, glucocorticoids have been reported to stimulate the activity of four enzymes involved in lipid synthesis: choline phosphate cytidylyltransferase, fatty acid synthase, phosphatidate phosphatase, and lysophosphatidylcholine:acyl-CoA acyltransferase (Gonzales and Ballard, 1989; Ballard, 1989; Rooney et al., 1990; Pope et al., 1988, Freese and Hallman, 1983; Brehier et al., 1977; Possmayer et al., 1979). Although cytidylyltransferase activity is increased by glucocorticoids, the amount of this enzyme is not increased (Rooney et al., 1990). In contrast, glucocorticoids increase the level of fatty acid synthase (Pope et al., 1988). Phosphatidate phosphatase and lysophosphatidylcholine:acyl-CoA acyltransferase activity are stimulated by glucocorticoids, but it is not known if the increase in enzyme is due to direct effects on enzyme levels or indirect effects on factors that may modify enzyme activity. In addition, glucocorticoids may indirectly affect type II cells by stimulating fibroblasts to produce fibroblast–pneumonocyte factor that then induces alveolar type II cell surfactant production (Smith and Post, 1989; see Chap. 13).
Lipids of Dermatophytes
Published in Rajendra Prasad, Mahmoud A. Ghannoum, Lipids of Pathogenic Fungi, 2017
The content of acylglycerol in M. gypseum and E. floccosum49,14 has been observed to be much higher than phospholipids. The fact that incorporation of [14C]-acetate into TG was more than that in other neutral lipids also suggests an active phosphatidate phosphatase in this dermatophyte.49 This enzyme also provides substrate, DG, for phospholipid synthesis by hydrolyzing PA. The presence of phosphatidate phosphatase has been reported in mitochondrial and microsomal fractions with a pH optimum of 6.0; however, E. floccosum enzyme was more active than that of M. gypseum. The enzyme from both the dermatophytes required Mg2+ for its activity and was sensitive to Mn2+, Fe2+ and B2+.75
Phosphatidate Phosphohydrolase in Plants and Microorganisms
Published in David N. Brindley, John R. Sabine, Phosphatidate Phosphohydrolase, 2017
J. L. Harwood, M. J. Price-Jones
Fractions rich in the acidic phosphatidate phosphohydrolase in mung bean also contained acidic p-nitrophenolphosphate activity. In order to eliminate the possibility that phosphatidate phosphohydrolysis was due to a nonspecific acid phosphatase, the developmental pattern of the enzyme was examined. Through 6 days of germination, phosphatidate phosphatase increased sixfold in activity in two stages while p-nitrophenylphosphatase did not increase for 3 days and then doubled (Figure 8). Together with enzyme purification data, these results indicated that the acidic phosphatidate phosphatase of mung beans was not due to acid phosphatase activity.
Coexistence of Three Different Mutations in a Male Infant: neurofibromatosis Type 1, Progressive Familial Intrahepatic Cholestasis Type 2 and LPIN3
Published in Fetal and Pediatric Pathology, 2022
Derya Altay, Orhan Gorukmez, Duran Arslan
Interestingly, homozygous mutation in LPIN3 gene was also detected in our patient’s clinical exome sequencing. LPINs (LPIN1, 2, 3) are phosphatidate phosphatase enzymes involved in triacylglycerol biosynthesis. They also play roles in the regulation of fatty acid oxidation and expression of inflammatory genes. LPIN3 is expressed by kidney, intestine, heart, liver, and adipose tissue. Although there is limited literature on the subject, it has been reported in one study that LPIN1 and LPIN3 act cooperatively in adipogenesis [4]. Michot et al. [7] reported that LPIN1 mutation is associated with severe rhabdomyolysis, but LPIN2 and LPIN3 are not associated with muscle diseases. Kahrizi et al. [8] found LPIN3 mutation to be associated with growth and developmental delay. In the present case, the patient had marked growth restriction. The feeding difficulty due to cholestasis and severe pruritus accompanied by neurofibromatosis probably contributed to his growth restriction. neurofibromatosis type 1- contributed to his growth restriction. The patient’s inability to gain weight despite the high calorie intake and elevated triglyceride was associated with the LPIN 3 mutation. It was thought that because of the LPIN3 mutation, of which little is known, that was found along with other diseases in this case, it could contribute to the existing literature. Because the patient is young, the patient’s follow-up continues in terms of growth and neurodevelopmental monitoring. In our case, any complication related to transplantation has not developed yet during the last six months since transplantation has been performed to the patient, however, the fact that the patient has not gained sufficient weight supports the LPIN3 mutation. This case is presented due to the coexistence of PFIC type 2, neurofibromatosis type 1, and LPIN3 mutations in the same patient.