首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The effects of Moringa oleifera (MO), Moringaceae on hyperlipidemia and hepatocyte ultrastructural changes caused by iron deficiency were investigated. Four-week-old male Wistar-strain rats were fed a control diet based on AIN-93G (C), an iron deficient diet (FeD), a FeD + 0.5% MO (FeD-m) diet, or a FeD + MO 1% (FeD-M) diet for 4 weeks. It was found that MO reduced iron-deficient diet-induced increases in serum and hepatic lipids with dose-dependent increases of serum quercetin and kaempherol, but did not prevent anemia. By electron microscopy, in iron deficient hepatocytes, slightly swollen mitochondria and few glycogen granules were observed, but glycogen granules increased and mitochondria were normalized by treatment with MO. Furthermore, lipoproteins were observed in the Golgi complex under treatment with MO. These results suggest a possible beneficial effect of MO in the prevention of hyperlipidemia and ultrastructural changes in hepatocytes due to iron-deficiency.  相似文献   

2.
The effects of blood components, nerve-cord severance, and ecdysone therapy on the posterior midgut epithelial cells of 5th-instar Rhodnius prolixus nymphs 10 days after feeding were analyzed by transmission electron microscopy. Cutting the nerve-cord of the blood-fed insects partially reduced the development of microvilli and perimicrovillar membranes (PMM), and produced large vacuoles and small electrondense granules; insects fed on Ringer's saline diet exhibited well developed microvilli and low PMM production; swolled rough endoplasmatic reticulum and electrondense granules; Ringer's saline meal with ecdysone led to PMM development, glycogen particles, and several mitochondria in the cytoplasm; epithelial cells of the insects fed on Ringer's saline meal whose nerve-cord was severed showed heterogeneously distributed microvilli with reduced PMM production and a great quantity of mitochondria and glycogen in the cytoplasm; well developed microvilli and PMM were observed in nerve-cord severed insects fed on Ringer's saline meal with ecdysone; Ringer's saline diet containing hemoglobin recovered the release of PMM; and insects fed on human plasma showed slightly reduced PMM production, although the addition of ecdysone in the plasma led to a normal midgut ultrastructural organization. We suggest that the full development of microvilli and PMM in the epithelial cells depends on the abdominal distension in addition to ingestion of hemoglobin, and the release of ecdysone.  相似文献   

3.
Vitamin A modulates inflammatory status, iron metabolism and erythropoiesis. Given that these factors modulate the expression of the hormone hepcidin (Hamp), we investigated the effect of vitamin A deficiency on molecular biomarkers of iron metabolism, the inflammatory response and the erythropoietic system. Five groups of male Wistar rats were treated: control (AIN-93G), the vitamin A-deficient (VAD) diet, the iron-deficient (FeD) diet, the vitamin A- and iron-deficient (VAFeD) diet or the diet with 12 mg atRA/kg diet replacing all-trans-retinyl palmitate by all-trans retinoic acid (atRA). Vitamin A deficiency reduced serum iron and transferrin saturation levels, increased spleen iron concentrations, reduced hepatic Hamp and kidney erythropoietin messenger RNA (mRNA) levels and up-regulated hepatic and spleen heme oxygenase-1 gene expression while reducing the liver HO-1 specific activity compared with the control. The FeD and VAFeD rats exhibited lower levels of serum iron and transferrin saturation, lower iron concentrations in tissues and lower hepatic Hamp mRNA levels compared with the control. The treatment with atRA resulted in lower serum iron and transferrin concentrations, an increased iron concentration in the liver, a decreased iron concentration in the spleen and in the gut, and decreased hepatic Hamp mRNA levels. In summary, these findings suggest that vitamin A deficiency leads to ineffective erythropoiesis by the down-regulation of renal erythropoietin expression in the kidney, resulting in erythrocyte malformation and the consequent accumulation of the heme group in the spleen. Vitamin A deficiency indirectly modulates systemic iron homeostasis by enhancing erythrophagocytosis of undifferentiated erythrocytes.  相似文献   

4.
The effects of nutritional conditions on alterations in condition factor, liver-somatic index, and hepatocyte ultrastructure in the olive flounder Paralichthys olivaceus were examined. Twelve weeks of starvation significantly decreased the condition factor and the liver-somatic index in the olive flounder. Hepatocytes underwent marked ultrastructural changes in response to 12 weeks of starvation. Compared to those of the initial control and fed group, the prominent features characterizing the hepatocytes of the starved group were: reduction in cell and nucleus size; apparent loss of nucleoli; condensation of chromatin; loss of stored glycogen; reduction of endoplasmic reticulum profile; increase in the number of electron-dense bodies containing large amounts of iron; and increased mitochondrial size. Results suggest that the histological changes caused by ultrastructural alterations in the hepatocytes can be used as alternative indicators to identify starvation in cultured P. olivaceus.  相似文献   

5.
The ultrastructure of liver cells was studied in rooks (Corvus frugilegus) living in radioactive and chemical contamination areas. The ultrastructure of liver cells from rook as well as jackdaw (Corvus monedula) and hooded crow (Corvus cornix) (Corvidae family) from a conventionally clean area was studied as control. Control hepatocytes proved to contain a great number of mitochondria, many of which were swollen and had clear matrix and disorganized cristae. The cristae nearly lacked glycogen and had abundant lipid droplets, which often tightly contacted mitochondria. The cytoplasm of hepatocytes in birds from both ecologically unfavorable areas had numerous mitochondria with the same ultrastructure. In contrast to control, the hepatocyte cytoplasm: (1) contained a lot of glycogen; (2) there were many lipid droplets, which directly contacted glycogen granules; and (3) had more abundant peroxisomes. In addition to normal erythrocytes, the sinusoids contained erythrocytes with mitochondria, vesicles, and lipid droplets in their cytoplasm. Analysis of many micrographs of lipid droplets contacting glycogen granules, mitochondria, peroxisomes, and cisterns of smooth endoplasmic reticulum allowed us to propose that glycogen is synthesized via gluconeogenesis from glycerol and products of fatty acid oxidation in the liver cell cytoplasm of rooks from ecologically unfavorable areas as distinct from control.  相似文献   

6.
Excised liver sections of the milkfish, Chanos chanos , fry and fingerlings were studied by transmission electron microscopy. The hepatocytes underwent marked ultrastructural alterations in response to food deprivation of 10-day starvation for fry and 2 months for the fingerlings. The prominent features characterizing the hepatocytes of starved fish were: a reduction of cell and nucleus size; apparent loss of nucleoli; condensation of chromatin material in fry; loss of stored glycogen; reduction of ER profiles; increase in the number of electron-dense bodies containing large amounts of iron in fingerlings; and an increase in mitochondrial size. These changes were reversible following short periods of re-feeding, i.e. 2 days for fry and 4 days for fingerlings, using natural food for the fry and formulated diet for the fingerlings.  相似文献   

7.
Summary In order to evaluate their suitability for physiological and ecotoxicological studies, hepatocytes were isolated from the common mudpuppy (Necturus maculosus) using a two-step collagenase perfusion. Hepatocytes in primary culture were investigated for 14 d using light and electron microscopy and biochemical analyses. A typical perfusion yielded 1.7×105 viable hepatocytes per gram body weight with an average viability of 86±5%. The majority of isolated cells remained in suspension and formed aggregates. The viability of hepatocytes in primary culture was dependent on a fetal calf serum (FCS) concentration and incubation temperature. Viability was best at 8°C in Leibovitz L-15 medium supplemented with 5% FCS. The ultrastructural characteristics of freshly isolated hepatocytes resembled those of N. maculosus hepatocytes in vivo. Whereas hepatocyte viability remained relatively stable (around 80%) up to 14 d in culture, electron microscopic analyses revealed changes at ultrastructural level. The majority of hepatocytes retained similar structural characteristics to those in vivo up to 4 d. Loss of cellular polarity, fractionation of rough endoplasmic reticulum, formation of autophagosomes, and successive exhaustion of cellular glycogen deposits were observed with increased time in culture. Functional integrity, as estimated by tyrosine aminotransferase induction, decreased during the culture period. Ultrastructural and biochemical analyses indicate the need for further improvement of culture conditions. Nevertheless, isolated hepatocytes in primary culture for up to 4 d can be recommended as a model for physiological and toxicological studies in lower vertebrates.  相似文献   

8.
Summary Estradiol injections increase serum level of calcium, amino acid, glucose, protein, ammonia and creatinine in immature Epinephelus akaara, and also increase levels of total lipid, cholesterol, phospholipid and esterified fatty acids. Hepatic protein, glycogen and lipid concentrations also rise after estradiol treatment, and some hepatic enzymes participating in the metabolism of nitrogen, lipid and carbohydrate, show increased activity. Serum vitellogenin levels are increased. Testosterone treatment increases serum protein, total lipid, cholesterol, amino acid and ammonia levels, and also hepatic glycogen content, but in contrast to estradiol treatment, testosterone does not change serum vitellogenin, glucose, calcium, phospholipid, esterified fatty acid and creatinine levels, nor the hepatic lipid and protein content. A small number of hepatic enzymes shows an increased activity. Vitellogenic fish show biochemical changes similar to that of estradiol-treated fish, but are different from those of immature fish. Estradiol treatment induces ultrastructural changes in the hepatocytes of immature fish that are similar to those found in vitellogenic fish. These include a proliferation of rough endoplasmic reticulum and Golgi apparatus, and an increase in glycogen and lipid, all indicative of enhanced metabolic activity.  相似文献   

9.
In the present study the establishment and characterization of a nontumorigenic liver epithelial cell line (HACL-1) derived from a human hepatocellular adenoma is described. The HACL-1 cells have a finite life span (i.e., they proliferate for a period of 2 months and then senesce), show cell–cell contact inhibition, do not grow in soft agar, are not tumorigenic when injected in nude mice, and possess a normal diploid karyotype. The cultured cells resemble hepatocytes, but exhibit some features of dedifferentiation. At the ultrastructural level the cells are endowed with round or oval nuclei, abundant cytoplasmic organelles, and varying amounts of glycogen. The rough endoplasmic reticulum is disorganized, while peroxisomes and matrix granules within mitochondria are lacking. HACL-1 cells are cytokeratin 18-positive as well as (transiently) albumin- and α-fetoprotein-positive, but do not express cytokeratin 19. Furthermore, no mutations were observed in exons 5–8 of the tumor suppressor genep53.Taken together these results show that HACL-1 cells are nontumorigenic proliferating liver epithelial cells, which might prove to be of great value in future studies on diverse aspects of human liver cell biology and carcinogenesis.  相似文献   

10.
Currently there is no good hepatocyte model for studying growth hormone (GH) function that reflects its normal physiological roles. Here we report the establishment of a functional hepatocyte cell line, SDRL-1, from the liver of young male spontaneous dwarf rats (SDR), with isolated GH deficiency. This line has been maintained in Dulbecco's Modified Eagle Medium (DMEM)/F12 medium supplemented with 10% fetal bovine serum (FBS) with retention of a near diploid karyotype for extended periods of time. When grown as a monolayer sheet, it displayed a pavement-like appearance and contact inhibition. These cells have a poorly developed rough endoplasmic reticulum (r-ER), few mitochondria and glycogen granules, and produce a small amount of albumin and α-fetoprotein, that is enhanced when grown on a collagen gel sponge. Human recombinant GH stimulated JAK2 and STAT5b tyrosine phosphorylation and IGF-I production in a concentration-dependent manner. When the cells were cultured with GH-supplemented medium, the number of mitochondria and glycogen granules increased together with the r-ER and Golgi apparatus. A number of microvilli were observed on the surface of the cultured cells, further suggesting that this cell line is composed of normally functioning hepatocytes. In summary, we established a novel hepatocyte cell line (SDRL-1), that appears to display normal function, which we propose can serve as a good in vitro model for studying GH-target organ interactions.  相似文献   

11.
目的通过对胰岛素用量不足条件下链脲佐菌素诱导的青少年食蟹猴1型糖尿病模型肝脏病理生理学的研究,探讨长期高血糖所致青少年食蟹猴肝损伤特点及机制。方法通过静脉注射68 mg/kg的链脲佐菌素,诱导4只3岁的食蟹猴成为1型糖尿病模型,然后经长期的血糖监测和静脉糖耐量实验来评价该模型的可靠性及稳定性,造模4年后,对模型猴进行血生化、PAS染色、苏丹III染色及普通病理和超微病理等指标的检测,另外选取4只健康与模型猴年龄匹配的猴作为正常对照组,同时进行相应的检测。结果与正常对照组比较,糖尿病猴血清学检测指标中总胆汁酸、尿素氮、谷丙转氨酶、谷草转氨酶、胆碱酯酶、乳酸脱氢酶、总胆固醇、甘油三酯和低密度脂蛋白胆固醇明显升高。组织化学染色结果显示,与正常猴比较,糖尿病猴中央静脉区肝实质细胞肿胀,肝细胞PAS染色(糖原染色)加深,苏丹Ⅲ染色(脂肪染色)阳性细胞增多;电镜结果显示糖尿病猴肝细胞内胞质糖原颗粒增多;线粒体电子密度显著增高,结构不清;窦周隙内含有大量脂滴的肝星状细胞明显增多。结论在长期胰岛素用量不足血糖控制不理想的条件下,青少年食蟹猴1型糖尿病模型肝脏特异性的病理改变是肝糖原贮积和含有大量脂滴的肝星状细胞增生,这些病理改变与非酒精性脂肪肝病的病变特点存在显著不同,但其机制目前尚不清楚。  相似文献   

12.
Ultrastructural changes of the terminal plates of the bushy receptors in the frog urinary bladder have been studied after two hours' exposition in 0.05% novocaine solution and one hour's exposition in 0.05% dicaine and trimecaine solution. During these periods a steady block of the receptor impulse activity develops. The local anesthetics essentially change ultramicroscopic structure of the terminals. The reaction to the anesthetics investigated has both some features in common and certain peculiarities. At each effect three types of changes can be determined, characterized with various degree of rearrangement in neurilemma, neuroplasm and organelles. Each type of the changes is supposed to reflect a certain phase of the plate reactive response. Specificities of the reaction to novocaine are minimal changes of mitochondria, accumulation of glycogen granules, deformity and decreasing amount of vesicles. Under dicaine effect mitochondria do not change, amount of vesicles increases, their form does not change; under trimecaine effect mitochondria undergo most noticeable alterations. The changes of the terminal plates observed are interpreted as adaptive. The effect of the local anesthetics on the receptors is not limited with the blockade of the sodium canals of the afferent fibers, in parallel, biochemical processes, occurring in cytosol of the terminals also change; their morphological manifestations are the ultrastructural changes observed.  相似文献   

13.
The authors studied ultrastructural changes of hepatocytes under the effect of alcohol. The greatest changes were revealed in the mitochondria. Physical activity and hypoprotein diet produced a significant influence on the results of alcohol poisoning. The first factor reduced, and the second enhanced the deleterious effect of alcohol.  相似文献   

14.
Summary The ultrastructure of the organs involved in urine production in the pond snailLymnaea stagnalis is described.The atrial wall, which has been assumed to act as an ultrafilter, shows little ultrastructural correspondence with other ultrafilters, such as the mammalian glomerulus. Thus, ultrafiltration probably can take place in systems lacking the typical podocytes. The atrium of the stylommatophoreHelix pomatia appeared to differ only in quantitative aspects — it is thicker — from that of the basommatophoresL. stagnalis andBiomphalaria glabrata.The reno-pericardial duct consists of ciliated columnar cells, which contain considerable amounts of glycogen.The cells of the kidney sac are characterized by the presence of large (5–20 ) excretion granules, which are constricted off together with part of the cytoplasm. In degenerating nephrocytes great numbers of lipid granules, probably arising from mitochondria, were found. Deposits of glycogen are present in the nephrocytes as well as in the cells of the ureter, suggesting the kidney to be a glycogen storing organ. The presence of glycogen is accompanied by that of an elaborate agranular endoplasmic reticulum.Although relative differences in the general ultrastructural pattern of the kidney sac and the ureter were found, some aspects of both epithelia—viz. the presence of numerous large mitochondria, a zone of microvilli at the free cell surface, and prominent infoldings of the basal and lateral cell membranes — suggest them to be involved in the reabsorption of solutes and in the transportation of ions and water.  相似文献   

15.
The morphological alterations of hepatocytes of cave‐dwelling salamander Proteus anguinus anguinus after food deprivation periods of one and 18 months were investigated and the concentrations of glycogen, lipids, and proteins in the liver were determined. Quantitative analyses of the hepatocyte size, the lipid droplets, the number of mitochondria, and volume densities of M and P in the hepatocytes were completed. After one month of food deprivation, the cytological changes in the hepatocytes are mainly related to the distribution and amount of glycogen, which was dispersed in the cytoplasm and failed to form clumps typical of normal liver tissue. After 18 months of food deprivation hepatocytes were reduced in size, lipid droplets were less numerous, peroxisomes formed clusters with small, spherical mitochondria, and specific mitochondria increased in size and lost cristae. Lysosomes, autophagic vacuoles, and clear vacuoles were numerous. The liver integrity was apparently maintained, no significant loss of cytoplasmic constituents have been observed. Biochemical analysis revealed the utilization of stored metabolic reserves in the liver during food deprivation. Glycogen is rapidly utilized at the beginning of the starvation period, whereas lipids and proteins are utilized subsequently, during prolonged food deprivation. In the Proteus liver carbohydrates are maintained in appreciable amounts and this constitutes a very important energy depot, invaluable in the subterranean environment. J. Morphol. 274:887–900, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
The aims of this work were to determine the effect of feeding BALB/c mice a diet containing culture materials of a citrinin producing strain of Penicillium citrinum (Thom). Changes in hematological parameters, serum chemistry and histological changes in liver, kidney and heart were determined. After 60 days, control treated (CT) mice appeared normal in all respects, whereas, the mice fed the feeds supplemented with Penicillium (CMT) showed decreased weight gain, lower hematocrits, increased serum alanine aminotransferase (ALT) and clear signs of renal and hepatotoxicity based on histological changes. Changes observed in the liver of CMT mice included portal and lobular infiltration of polymorphonuclear cells, with concomitant hepatocellular necrosis, hepatic steatosis, prominent Kupffer's cells, hemosiderin granules in the cytoplasm of periportal hepatocytes and other lipid inclusions in the surrounding mitochondria were also observed. Our findings suggest that in vivo, P. citrinum Thom metabolites, which contain citrinin, could cause illnesses such as toxic hepatitis or intravascular hemolysis.  相似文献   

17.
An ultrastructural and morphometric study was performed on mitochondria of euthermic, hibernating and arousing hazel dormice (Muscardinus avellanarius), in order to investigate possible modifications during the seasonal cycle. Hepatocytes, pancreatic acinar cells and brown adipocytes were considered. Our results demonstrated that: (1) the general morphology of mitochondria of all cell types shows slight modifications during the seasonal cycle; (2) mitochondrial size and inner membrane length significantly increase from euthermia to hibernation and decrease upon arousal in all cell types; (3) mitochondrial matrix granules drastically increase in number during hibernation and decrease upon arousal in hepatocytes and pancreatic acinar cells, whereas they do not change in brown adipocytes. These structural modifications are probably related to the changes in cellular energy needs during the euthermia-hibernation-arousal cycle.  相似文献   

18.
19.
Summary A developmental study at the electron microscopic level was conducted of the fat body cells of Hyalophora cecropia (L.). During the last larval instar the fat body increases in volume and the cells exhibit a well developed rough endoplasmic reticulum and protein bodies of diverse sizes. In the pupal fat body, the protein bodies appear to be enclosed by a double membrane and contain glycogen granules, ribosomes and mitochondrion-like structures. In addition, there are large lipid globules, cytolysomes and rough endoplasmic reticulum. The ultrastructure of the protein bodies suggests the development of large bodies by fusion of smaller protein bodies. Changes in fat body cell ultrastructure were followed during adult development and cytological evidence was obtained for the depletion of protein, glycogen and lipid in the female during this period. The female adult fat body cell contains free ribosomes, protein bodies, many mitochondria, a few lipid globules and glycogen granules. The male moth fat body cells have many mitochondria, a few glycogen granules, essentially no protein bodies, but an abundance of large lipid globules.Studies on the influence of egg maturation on the morphology of the fat body of Hyalophora gloveri (L.) revealed that ovariectomy of pupae yielded adults having more fat body than normal females, and that the fat body cells of the ovariectomized animals contained more glycogen, lipid and protein. Male pupae receiving ovarian implants developed into adults containing eggs and possessed more fat body than normal females but less than normal males. Very few glycogen granules were found in the fat body cells of normal males or males with implanted ovaries.Supported by grant AM-02818 from the National Institutes of Health.We thank Dr. James Oschman for his helpful suggestions and constructive criticisms.  相似文献   

20.
In the experiment performed on 25 non-inbred male rats ultrastructural changes in cardiomyocytes of the hypertrophied heart have been studied under conditions of stress caused by immobilization and possibility to correct these changes by means of thyroid hormones. The stress intensifies destructive lesions in a number of organelles++, which develop at a prolonged hypertrophy, decreases essentially the ratio mitochondria/myofibrils in section area. Small doses of the thyroid hormones protect the hypertrophied heart from the damaging effect of the stress: prevent the stress-induced+ decrease in the ratio mitochondria/myofibrils, as well as stimulate development of the regenerative-adaptive processes (increase in size and number of mitochondria and their crists, elements of the sarcoplasmic reticulum, glycogen granules, increase in section areas of their nuclei and chromatin in them). The thyroid hormones restrict essentially decrease in correlation of organelles++, resulted from hypertrophy. Thus, the stress-induced disturbances in ultrastructure of the hypertrophied heart can be prevent by means of the thyroid hormones, administered in small doses.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号