scholarly journals Morphometric analysis of the ultrastructural changes in rat liver induced by the peroxisome proliferator SaH 42-348.

1976 ◽  
Vol 71 (3) ◽  
pp. 768-780 ◽  
Author(s):  
D E Moody ◽  
J K Reddy

The changes occurring in hepatocytes of F-344 male rats during a 3-wk treatment with a hypolipidemic agent, 1-methyl-4-piperidyl-bis [p-chlorophenoxy]acetate (SaH 42-348), have been evaluated by morphometric and biochemical methods. The twofold increase in liver weight resulted from a significant increase in hepatocyte cytoplasm as well as a moderate increase in the number of liver cells. The peroxisome population and SER played an overwhelming part in the hypertrophy of hepatocytic cytoplasm. The relative volume and the surface density of peroxisomes volume resulted from an increased ninefold and sevenfold, respectively. The increase in the collective peroxisome volume resulted from an increase in both the number and the average volume of peroxisomes. The SER also demonstrated a substantial increase in these values. The relative volume and surface density of mitochondria were not significantly altered in comparison to controls, while these values for RER decreased onefold. Studies on the lobular distribution of cytoplasmic organelles before and during treatment revealed that the relative volume and surface density of peroxisomes and SER increased from periportal to centrilobular cells of the hepatic lobule, whereas mitochondrial values decreased from periportal to centrilobular cells. The RER values were fairly constant in different parts of the hepatic lobule. The increase in peroxisome and SER volume and surface area was first evident within the first 3 days of SaH 42-348 treatment and these values continued to increase, reaching a steady state within 2 wk. The time course of increase in catalase and carnitine acetyltransferase activities correlated with the morphometric data on the peroxisomes. After cessation of SaH 42-348 treatment, the peroxisome values decreased rapidly within the first 3 days and reached control levels within 1 wk. Moderate reduction in SER values occurred after withdrawal of the drug, but these values remained higher than controls even after 2 wk, suggesting that the reduction in the amount of circulating peroxisome proteins may result in empty SER channels. On the 4th day of drug withdrawal a significant increase in the relative volume and surface density of lysosomes was observed, suggesting that these organelles may play some part in the removal of cellular membranes. However, the rapid reduction in peroxisome values after SaH 42-348 withdrawal appears to be due to cessation of enhanced peroxisome protein synthesis.

Author(s):  
K.W. Lee ◽  
R.H. Meints ◽  
D. Kuczmarski ◽  
J.L. Van Etten

The physiological, biochemical, and ultrastructural aspects of the symbiotic relationship between the Chlorella-like algae and the hydra have been intensively investigated. Reciprocal cross-transfer of the Chlorellalike algae between different strains of green hydra provide a system for the study of cell recognition. However, our attempts to culture the algae free of the host hydra of the Florida strain, Hydra viridis, have been consistently unsuccessful. We were, therefore, prompted to examine the isolated algae at the ultrastructural level on a time course.


2021 ◽  
Vol 22 (2) ◽  
pp. 811
Author(s):  
Huifang Yan ◽  
Peisheng Mao

Melatonin priming is an effective strategy to improve the germination of aged oat (Avena sativa L.) seeds, but the mechanism involved in its time-course responses has remained largely unknown. In the present study, the phenotypic differences, ultrastructural changes, physiological characteristics, and proteomic profiles were examined in aged and melatonin-primed seed (with 10 μM melatonin treatment for 12, 24, and 36 h). Thus, 36 h priming (T36) had a better remediation effect on aged seeds, reflecting in the improved germinability and seedlings, relatively intact cell ultrastructures, and enhanced antioxidant capacity. Proteomic analysis revealed 201 differentially abundant proteins between aged and T36 seeds, of which 96 were up-accumulated. In melatonin-primed seeds, the restoration of membrane integrity by improved antioxidant capacity, which was affected by the stimulation of jasmonic acid synthesis via up-accumulation of 12-oxo-phytodienoic acid reductase, might be a candidate mechanism. Moreover, the relatively intact ultrastructures enabled amino acid metabolism and phenylpropanoid biosynthesis, which were closely associated with energy generation through intermediates of pyruvate, phosphoenolpyruvate, fumarate, and α-ketoglutarate, thus providing energy, active amino acids, and secondary metabolites necessary for germination improvement of aged seeds. These findings clarify the time-course related pathways associated with melatonin priming on promoting the germination of aged oat seeds.


1975 ◽  
Vol 38 (4) ◽  
pp. 623-629 ◽  
Author(s):  
D. B. Gail ◽  
G. D. Massaro ◽  
D. Massaro

We examined the time course of the influence of cycloheximide on descending pressure-volume curves of excised lungs and on protein and lecithin synthesis and oxygen consumption by lung slices. We also looked at the influence of cycloheximide on granular pneumocyte ultrastructure. Excised lungs from cycloheximide-treated animals are more compliant than controls. After ventilation with air, lungs from control and cycloheximide animals show increased retractive forces and a shift to the right of the deflation P-V curve. Incubation at 38 degrees C for 30 min reverses these changes in control lungs, but not in lungs from cycloheximide-treated rabbits. There is no change in liquid delfation P-V curves after cycloheximide. Cycloheximide causes an immediate decrease of 50% in incorporation of radioactive leucine into protein by lung slices. Incorporation of radioactive palmitate into lecithin and oxygen consumption are also decreased by 50% 6 h after cycloheximide. Lamellar bodies in granular pneumocytes are smaller after cycloheximide. Cycloheximide causes a significant increase in the surface density of the lamellar body envelope. Cytoplasmic area of granular pneumocytes is increased after cycloheximide.


Endocrinology ◽  
2011 ◽  
Vol 152 (3) ◽  
pp. 869-882 ◽  
Author(s):  
Camilla A.-M. Glad ◽  
Edward E. J. Kitchen ◽  
Gemma C. Russ ◽  
Sophie M. Harris ◽  
Jeffrey S. Davies ◽  
...  

Reversed feeding (RF) is known to disrupt hormone rhythmicity and metabolism. Although these effects may be mediated in part by phase inversion of glucocorticoid secretion, the precise mechanism is incompletely characterized. In this study, we demonstrate that acute nocturnal food deprivation in male rats suppressed the amplitude of spontaneous GH secretion during the dark phase by 62% (P < 0.001), without affecting baseline secretion. Prolonged RF, which reduced pituitary weight (by 22%; P < 0.05), also suppressed GH pulse height sufficiently to reduce skeletal growth (by 4–5%; P < 0.01) and terminal liver weight (by 11%; P < 0.001). Despite this suppression of the GH axis, proportionate adiposity was not elevated, probably due to the accompanying 16% reduction in cumulative food intake (P < 0.01). We demonstrate that RF also resulted in phase inversion of core clock gene expression in liver, abdominal white adipose tissue (WAT) and skeletal muscle, without affecting their expression patterns in the suprachiasmatic nucleus. In addition, RF resulted in phase inversion of hepatic peroxisome proliferator-activated receptor γ2 mRNA expression, a 3- to 5-fold elevation in fatty acid synthase mRNA in WAT in both light- and dark-phase samples (P < 0.01) and an elevation in muscle uncoupling protein 3 mRNA expression at the beginning of the light phase (P < 0.01). Consumption of a high-fat diet increased inguinal (by 36%; P < 0.05) and retroperitoneal WAT weight (by 72%; P < 0.01) only in RF-maintained rats, doubling the efficiency of lipid accumulation (P < 0.05). Thus, RF not only desynchronizes central and peripheral circadian clocks, and suppresses nocturnal GH secretion, but induces a preobesogenic state.


2005 ◽  
Vol 21 (3) ◽  
pp. 351-361 ◽  
Author(s):  
Ralph L. House ◽  
Joseph P. Cassady ◽  
Eugene J. Eisen ◽  
Thomas E. Eling ◽  
Jennifer B. Collins ◽  
...  

Gene expression was measured during t10c12-CLA-induced body fat reduction in a polygenic obese line of mice. Adult mice ( n = 185) were allotted to a 2 × 2 factorial experiment consisting of either nonobese (ICR-control) or obese (M16-selected) mice fed a 7% fat, purified diet containing either 1% linoleic acid (LA) or 1% t10c12-CLA. Body weight (BW) by day 14 was 12% lower in CLA- compared with LA-fed mice ( P < 0.0001). By day 14, t10c12-CLA reduced weights of epididymal, mesenteric, and brown adipose tissues, as a percentage of BW, in both lines by 30, 27, and 58%, respectively, and increased liver weight/BW by 34% ( P < 0.0001). Total RNA was isolated and pooled (4 pools per tissue per day) from epididymal adipose ( days 5 and 14) of the obese mice to analyze gene expression profiles using Agilent mouse oligo microarray slides representing >20,000 genes. Numbers of genes differentially expressed by greater than or equal to twofold in epididymal adipose ( days 5 and 14) were 29 and 125, respectively. It was concluded that, in adipose tissue, CLA increased expression of uncoupling proteins (1 and 2), carnitine palmitoyltransferase system, tumor necrosis factor-α ( P < 0.05), and caspase-3 but decreased expression of peroxisome proliferator-activated receptor-γ, glucose transporter-4, perilipin, caveolin-1, adiponectin, resistin, and Bcl-2 ( P < 0.01). In conclusion, this experiment has revealed candidate genes that will be useful in elucidating mechanisms of adipose delipidation.


2021 ◽  
Vol 11 (6) ◽  
pp. 137-142
Author(s):  
Mykhailo Hnatiuk ◽  
Lesia Rubas

Aim: to study morphometrically the peculiarities of remodeling of chondrocytes of the articular surfaces of the temporomandibular joint in hyperglycemia.Materials and methods: Quantitative morphological methods were used to study diameters of chondrocytes and their nuclei, nuclear-cytoplasmic relationship in these cells, relative volume of damaged chondrocytes, intercellular-chondrocytic relationship in mature chondrocytes of the articular surfaces of the temporomandibular joint of 45 laboratory mature white male rats with simulated diabetes.Results: A comprehensive analysis of the morphometric parameters presented in the article showed that they did not differ in the articular surfaces of the temporal fossa and mandibular head of the intact temporomandibular joint. The expressed structural changes of chondrocytes were revealed at a monthly and a two-month diabetic arthropathy of this joint.Conclusions: Proceeded studies and obtained results suggest that prolonged hyperglycemia leads to diabetic arthropathy of the TMJ, which is characterized by atrophy of chondrocytes, violation of nuclear-cytoplasmic relationships, an increase in the relative volume of damaged chondrocytes and volume of intercellular substance. The detected changes in quantitative morphological parameters depended on the duration of hyperglycemia and dominated in the cartilaginous tissue of the articular surface of the mandibular head.


2021 ◽  
Vol 25 (2) ◽  
pp. 178-188
Author(s):  
Sabir Ouahhoud ◽  
◽  
Ilham Touiss ◽  
Amine Khoulati ◽  
Iliass Lahmass ◽  
...  

Introduction: The present study investigated the hepatoprotective effects of stigmas, tepals and leaves of Crocus sativus on carbon tetrachloride (CCL4) induced liver injury in rats. Methods: Hydroethanolic extracts of Crocus sativus (stigmas, tepals and leaves) were administrated daily for 14 days by oral gavage. In the present study, 30 male rats divided into five groups were treated as 1: normal rats gavaged with distilled water; 2: intoxicated rats gavaged with distilled water and injected with CCL4; 3: rats treated with stigmas extract and injected with CCL4; 4: rats treated with tepal extract and injected with CCL4; 5: rats treated with leaf extract and injected with CCL4. Bodyweight and the relative liver weight were determined. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), total cholesterol, triglycerides, bilirubin direct and total, total protein, albumin, urea and creatinine measured in plasma. Malondialdehyde (MDA) was quantified in liver homogenate. Results: The experimental data showed that the stigmas and tepals extracts significantly prevented weight body loss and improved the relative liver weight. They significantly protected against elevation of ALT, AST, direct bilirubin, total bilirubin, LDH, ALP, creatinine and MDA. Also, they enhanced significantly total proteins and albumin compared to the CCL4 control group. Moreover, leaves reduced ALT, AST, total bilirubin, LDH and MDA significantly. Conclusion: In conclusion, these results suggest that tepals, stigmas, and leaves extracts of Crocus sativus have hepatoprotective effects on CCL4 induced liver injury in rats.


2022 ◽  
Vol 12 (1) ◽  
pp. 112-120
Author(s):  
Jieqi Gong ◽  
Huanhua Lu

The objective of this study was to investigate the molecular mechanism of the histopathological characteristics of liver cirrhosis (LC) complicated with acute kidney injury (AKI) and the signaling pathway of silent information regulator 1 (SIRT1)-peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) during the pathogenesis of LC. 20 healthy male rats with AKI complicated by laparoscopic cholecystectomy were selected and divided randomly into control group (C group), lipopolysaccharide (LPS) group, bile duct ligation (BDL) group, and model group (lipopolysaccharide+BDL) (D group). The indexes of all the rats were determined, including serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), sarcoplasmic enzyme (Scr), and blood urea nitrogen (BUN); the SIRT1 and PGC-1α expressions in renal tissues of rats from each group was detected. Results showed that the AST and ALT levels in BDL group and D group were higher markedly than those before surgery (P < 0.05). The serum levels of Scr and BUN in D group 4 hours after LPS injection increased hugely compared with before injection (P < 0.05). Compared with BDL group, the protein levels of SIRT1 and PGC-1α in renal tissue of group D were decreased sharply (P < 0.05), and the SIRT1 protein expression was positively correlated with PGC-1α (r = 0.836 and P < 0.01). When LC were complicated with AKI, SIRT1 activity was reduced and PGC-1α expression was inhibited. Moreover, SIRT1-PGC-1α signaling pathway played a protective role in pathogenesis of LC complicated with AKI.


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