Increase In Size Of Hepatocytes Research Articles

Ameliorative effect of Nigella sativa conjugated silver nanoparticles against chromium-induced hepatotoxicity and renal toxicity in mice

Hexavalent chromium induces oxidative stress in the liver and kidney. Therefore an in vivo study was designed to investigate the modulatory effect of biosynthesized AgNP against Cr (VI) induced hepatotoxicity and nephrotoxicity. The organs index, serum level of ALT, AST, ALP, MDA, total protein and creatinine were measured. The histopathology and micrometry of the liver and kidney were examined. The liver index was significantly increased (0.098 ± 0.13 g) with slight increase in kidney index in Cr exposed group. The serum level of ALT (163.0 ± 5.5 U/L), AST (484.0 ± 10.7 U/L), ALP (337.6 ± 9.6 U/L), MDA (641.2 ± 29.2 U/L), and creatinine (2.9 ± 0.2 mg/dL) were significantly increased (P ≤ 0.05) with significant decrease in total protein level (2.9 ± 0.2 g/dL) (P ≤ 0.05) in chromium treated group. In histopathology, distorted hepatic cords, necrosis, damaged glomerulus and Bowman’s capsule were observed. Micrometric studies of the liver and kidney showed significant increase in size of hepatocytes (1188.2 ± 467.7 µ2) and their nuclei (456.4 ± 206.7 µ2), ACSA of Bowman’s capsule (11835.5 ± 336.7 µ2) and glomerulus (9051.8 ± 249.8 µ2) in Cr (VI) treated group. The size of brush border (10.1 ± 3.0 µ) was significantly reduced in Cr (VI) treated group however the ACSA of lumen was not significantly changed. With the administration of NSSE and Nigella sativa AgNPs, decreased the oxidative damage caused by Cr (V).

Effect of Garcinia Cambogia Containing Co;mmercially Avaible Weight Reducing Agent on Morphology of Hepatocytes An Experimental Study

<p><strong>Background and Objective:</strong> Obesity is the adverse outcome of modern living which has affected both the physical and mental health. Slim Smart and Ultra Slim Plus are the most frequently purchased over the counter products by desperate obese persons in Pakistan having Garcinia cambogia (GC) as the main active ingredient. This study is conducted to determine the effect of GC containing Slim Smart and Ultra Slim Plus drugs on the morphology of hepatocytes in male albino mice.</p>
 <p><strong> Methods:</strong> Ninety albino mice were divided into control group A, experimental groups B and C receiving Slim Smart and Ultra Slim Smart respectively. Each group was further divided into subgroup I and II and the drug was administered to experimental groups for 4 and 8 weeks respectively via oral gavage. After the completion of experiment, histological examination of liver was conducted.</p>
 <p><strong> Results:</strong> Marked enlargement of hepatocytes was observed in experimental groups B and C (both I & II) along with ballooning degeneration and fatty change in the cytoplasm.</p>
 <p><strong>Conclusion:</strong> Both Slim Smart and Ultra Slim Plus has hepatotoxic effects resulting in increase in hepatocyte size, ballooning degeneration and fatty change in liver cells. </p>

EFFECT OF STARVATION AND REFEEDING DIETS CONTAINING DIFFERENT PROTEIN LEVELS ON COMPENSATORY GROWTH AND HISTOPATHOLOGICAL CHANGES OF NILE TILAPIA (OREOCHROMIS NILOTICUS)

This study was conducted to evaluate the effect of deprivation and refeeding of diets containing different levels of protein on growth performance, liver histopathological changes and intestinal morphometric in Nile tilapia (Oreochromis niloticus). One hundred and twenty Nile tilapia fish weighing 35± 0.5 g were randomly distributed into 12 aquarium tanks (10 fish/ tank). Triplicate tanks were assigned for each dietary regimen. Four groups were firstly fasted for 8 weeks then refed for the following 4 weeks on diets containing different levels of protein (26%, 28%, 30%, and 32%). Fish were weighed during starvation and refeeding period.The body weight (BW) of fish fed diet containing 28% & 30% were significantly higher than that of other groups. Condition factor (CF) of fish fed diet containing 30 & 32% CP was higher than that of other groups. Liver of Nile tilapia during starvation showed small hepatocytes. Refeeding results in gradual increase in size of hepatocytes of fish in different groups and with increased villous height, perimeter, area and number of goblet cells (GCs). Our results indicate that a diet containing 28, 30% of CP could be optimal in relative growth compensation after starvation. CF revealed better values in fish fed diets containing 30 & 32% of CP. Moreover, starved Nile tilapia has the ability to recover the normal liver histology after period of refeeding.

EFFECTS OF DEXAMETHASONE ON LIVER HISTOLOGY OF ADULT ALBINO MICE

Objective: In this study the effects of dexamethasone on liver histology in animal model were evaluated.
 Design: This study comprised of 120 albino adult mice which were divided in four groups; one control and three experimental groups (on ascending doses of dexamethasone) administered for twelve weeks. The mice were sacrificed at 4, 8 and 12 weeks and liver histology was examined. The liver was serially sectioned and stained with Haematoxylin and Eosin stains. A comparison of any dose-related changes of dexamethasone on the liver was made with the control group. One way ANOVA was applied to compare weight of liver, size of hepatocyte and nuclear changes in all groups.
 Results: Histological analysis showed that dexamethasone induced increase in weight of liver, an increase in hepatocyte size in relation to the dose given. Nuclear changes showed pyknosis with heightened staining. Cellular infiltration and portal vein congestion.
 Conclusion: These findings suggest thatdexamethasone has deleterious effects on liver histology.

Suppression of autophagy during liver regeneration impairs energy charge and hepatocyte senescence in mice

Autophagy is a homeostatic mechanism that regulates protein and organelle turnover and uses the amino acids from degraded proteins to produce adenosine 5'-triphosphate (ATP). We investigated the activity of autophagy-associated pathways in liver regeneration after partial hepatectomy (PHx) in liver-specific autophagy-related gene 5 (Atg5) knockout (KO) mice. Liver regeneration was severely impaired by 70% PHx, with a reduction in postoperative mitosis, but a compensating increase in hepatocyte size. PHx induced intracellular adenosine triphosphate and β-oxidation reduction as well as injured cellular mitochondria. Furthermore, PHx in Atg5 KO mice enhanced hepatic accumulation of p62 and ubiquitinated proteins. These results indicated that reorganization of intracellular proteins and organelles during autophagy was impaired in the regenerating liver of these mice. Up-regulation of p21 was associated with hepatocyte senescence, senescence-associated β-galactosidase expression, irreversible growth arrest, and secretion of senescence-associated molecules, including interleukin (IL)-6 and IL-8. These findings indicate that autophagy plays a critical role in liver regeneration and in the preservation of cellular quality, preventing hepatocytes from becoming fully senescent and hypertrophic.

Focus

Focus

Dissecting the role of the immune system in liver injury and hepatocarcinogenesis”

Background: Activation of the immune system by tumor cells might result in eradication of malignant cells. In this regard, modulation of the immune system has been shown to increase carcinogenesis in several knock-out models. However, there is increasing evidence that chronic activation of the immune system in pre-malignant tissues might also promote tumor development. In order to characterize the role of the immune system in chronic liver injury and hepatocarcinogenesis mouse model of hereditary tyrosinemia type 1 (HT1) was used. HT1 is a genetic defect of tyrosine catabolism and is characterized by an extremely high susceptibility for liver cancer. The only effective therapy is 2-(2-nitro-4-trifluor-methylbenzyl)-1,3 cyklohexanedion-(NTBC)-treatment that blocks an upstream enzyme in the tyrosine catabolism. Methods: To induce flares of liver injury NTBC was repeatedly withdrawn for 21 days followed by 5-day-NTBC-treamtent to allow partial liver regeneration. Livers were harvested and liver injury was analyzed by immunohistochemistry and biochemistry. Bi-potent progenitor cells and inflammatory cells in the liver were analyzed and quantified by FACS analysis and immunohistochemistry. Gene expression arrays and RT-PCR arrays has been performed to reveal changes in gene expression profile. Results: Flares of liver injury induced a severe hepatitis and significantly accelerated liver tumor development. Liver regeneration occurred by several mechanism including proliferation of differentiated hepatocytes, increase in size of hepatocytes and activation of liver progenitor cells. Liver injury was accompanied by a massive infiltration of T-cells, Monocytes and Macrophages in the liver. To determine the role of the immune system, Fah-/- Rag-2-/- IL-2-/- mice (FCR) were treated in the same way. Interestingly, survival of alymphoid Fah-/- mice was dramatically shorter than that of Fah-/- mice. Almost 70% of the FCR mice died within the first 2 months whereas over 90% of Fah-/- mice survived the FAA-induced hepatitis suggesting that the immune system plays an important pro-survival role during chronic liver injury. Interestingly however, liver tumor development was completely suppressed in surviving FCR mice. To better understand the role of the immune system in the Fah-/- model, extensive molecular (Microarrays, WB) and immunological (RT-PCR arrays/FACS) profiling, hepatocyte and hematopoietic stem cell transplantations, adoptive transfers of specific immune cell populations were performed and additional immune-suppressed mice were generated. Conclusion: Our analysis identifies distinct functions of the immune system, which are required for liver regeneration and survival and for hepatocarcinogenesis on the other hand. Targeting specifically the tumor-promoting pathways may be an attractive chemopreventive strategy for patients at risk.

Effects of Acetaldehyde on Hepatocyte Glycerol Uptake and Cell Size: Implication of Aquaporin 9

The effects of ethanol and acetaldehyde on uptake of glycerol and on cell size of hepatocytes and a role Aquaporin 9 (AQP9), a glycerol transport channel, were evaluated. The studies were done in primary rat and mouse hepatocytes. The uptake of [(14) C] glycerol was determined with hepatocytes in suspension. For determination of cell size, rat hepatocytes on coated dishes were incubated with a lipophilic fluorochrome that is incorporated into the cell membrane and examined by confocal microscopy. A three-dimensional z scan of the cell was performed, and the middle slice of the z scan was used for area measurements. Acute exposure to acetaldehyde, but not to ethanol, causes a rapid increase in the uptake of glycerol and an increase in hepatocyte size, which was inhibited by HgCl(2) , an inhibitor of aquaporins. This was not observed in hepatocytes from AQP9 knockout mice, nor observed by direct application of acetaldehyde to AQP9 expressed in Xenopus Laevis oocytes. Prolonged 24-hour exposure to either acetaldehyde or ethanol did not result in an increase in glycerol uptake by rat hepatocytes. Acetaldehyde decreased AQP9 mRNA and AQP9 protein, while ethanol decreased AQP9 mRNA but not AQP9 protein. Ethanol, but not acetaldehyde, increased the activities of glycerol kinase and phosphoenolpyruvate carboxykinase. The acute effects of acetaldehyde, while mediated by AQP9, are probably influenced by binding of acetaldehyde to hepatocyte membranes and changes in cell permeability. The effects of ethanol in enhancing glucose kinase, and phosphoenolpyruvate carboxykinase leading to increased formation of glycerol-3-phosphate most likely contribute to alcoholic fatty liver.

Highlights From The Literature

Highlights From The Literature

Effects of Phos-Chek G75-F and Silv-Ex on developing northern bobwhite quail (Colinus virginianus).

Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex(R) (SE), a foam-suppressant chemical, and Phos-Chek(R) G75-F (PC), a fire retardant chemical, on day 4 or day 11 of incubation. An attempt was made to relate the treatment concentrations to the actual field application levels. Mortality appeared higher in most groups exposed on day 11 than on day 4, suggesting that on day 11 the extensive chorioallantoic vascular network permitted greater uptake of chemical. Only 24-60% of the embryos survived to hatch at exposure concentrations of 202, 269, and 454 g/L PC when treated on incubation day 11. At higher concentrations including 681956, and 1211 g/L PC, the compound did not completely dissolve in water and clumped on eggshells, resulting in greater hatching success. Exposures to SE at 100 g/L on incubation day 11 did not significantly affect hatching success of embryos but did significantly reduce the percent hematocrit in blood compared with controls. Incubation day 11 exposure to 202 and 1211 g/L PC led to a significant increase in plasma aspartate aminotransferase, and day 4 exposure to 1211 g/L PC resulted in a significant increase in alanine aminotransferase. In addition to elevated liver enzymes, these treatments resulted in a decrease in the number of hepatocyte profiles (1211 g/L PC at day 4 and day 11) and an increase in hepatocyte size (202 and 1211 g/L PC at day 11) in hatchlings. A combination of SE and PC was synergistic (202 g/L PC and 50 g/L SE) at day 11 of incubation with respect to decreased hatching success and reduced bone lengths. However, lower concentrations of SE (10 g/L or 30 g/L) combined with 202 g/L of PC appeared antagonistic. This may be due to SE, as a surfactant, altering the ability of PC to penetrate the egg. Our results show fewer adverse effects following exposure to SE than to PC; therefore application of SE may be less harmful to breeding bird populations.

Morphological manifestations of compensatory and adaptive processes in the liver during aging

Light and electron microscopy and morphometry revealed an age-related increase in the average size of hepatocytes and their nuclei in 24- and 30-month-old rats compared to 8-month-old animals, the density of hepatocytes distribution per area unit being decreased. In 24-month-old rats the number of binuclear hepatocytes increased with a subsequent decrease in their number in 30-month-old animals, which accounted for the shift in regeneration processes during ageing to predominantly intracellular one. The number of sinusoidal cells per area unit in three age groups was statistically similar. The results of morphometry and electron microscopy suggest that the compensatory-adaptive processes during hepatocyte ageing were mediated by intracellular regeneration, which led to cellular and nuclear hypertrophy similar to that observed in cells of static population (neurons, cardiomyocytes).

Initial rate of sodium taurocholate uptake in isolated elutriated hepatocytes from untreated and phenobarbital-treated rats

The initial rate of sodium taurocholate uptake was measured in rat hepatocytes separated by centrifugal elutriation into five cell fractions whose difference in size was verified by flow cytometry. The hepatocytes were prepared from untreated and phenobarbital-treated rats. For untreated animals. the initial rate of taurocholate uptake at concentrations of 5 or 50 μM was the same for hepatocytes prior to fractionation and for each of the five elutriated fractions. Treatment of the animals with phenobarbital was associated with a significant increase in hepatocyte size in all fractions and caused a significant increase in the initial uptake rate. The extent of the rate increase in hepatocytes prior to fractionation was similar to that observed for each of the five hepatocyte subpopulations. Our observation indicates that phenobarbital causes a significant increase in the initial rate of sodium taurocholate uptake and suggests that large and small hepatocytes possess no inherent differences controlling the initial uptake process.

On the characteristics of alcohol-induced liver enlargement and its possible hemodynamic consequences

Chronic consumption of alcohol leads to an increase in liver weight, primarily due to an increase in hepatocyte volume. About 50–60% of such an increase is due to an increase in intracellular water. Accumulation of intracellular K + osmotically accounts for about one half of the increase in intracellular water, while an increase in soluble proteins plays only a minor role in such an increase in cell volume. The increase in intracellular water is accompanied by a relative reduction in water in the extracellular space, probably due to compression of the extracellular volume by the enlarged hepatocytes. It is suggested that such an increase in hepatocyte size, with an attending reduction of the extracellular volume, results in an increased resistance to blood flow through the liver and thus in an increase in portal pressure. In alcoholics, portal and intrahepatic pressure correlate with cell size both in cirrhotics (r=0.79) and in non-cirrhotics (r=0.74), thus suggesting that cell enlargement plays a major role in the production of portal hypertension in the alcoholic.

Correlation of intrahepatic pressure with collagen in the Disse space and hepatomegaly in humans and in the rat

In 70 alcoholic patients the amount of collagen in the space of Disse was compared, using an electron microscopic graded score, to the height of the intrahepatic pressure. A highly significant correlation was found between the amount of collagen and intrahepatic pressure in the group as a whole (r = 0.84; p < 10−6), as well as in subgroups of 30 alcoholic patients with normal livers or steatosis (r = 0.83; p < 10−6), 9 patients with alcoholic hepatitis (r = 0.81; p < 0.01), and 31 with cirrhosis (r = 0.86; p < 10−6). A nonparametric correlational analysis for the complete group also showed a significant relationship (rho = 0.85; p < 10−6) between collagen scores and intrahepatic pressure. In 60 patients hepatocyte surface area was measured in the biopsies. In these, hepatocyte surface area significantly correlated with intrahepatic pressure (r = 0.68; p < 10−7). No correlation was found between intrahepatic pressure and fat, alcoholic hyalin, or terminal hepatic vein sclerosis. Only with necrosis (r = 0.38; p < 0.001) and inflammation (r = 0.29; p < 0.05) was there a significant relationship with intrahepatic pressure. Chronic ethanol administration for 4 wk in liquid diets to young Wistar rats produced a 50% hepatomegaly due to an increase in hepatocyte size. Intrahepatic pressure in the rats receiving alcohol (19.3 ± 2.3 mmHg) was significantly higher than in the controls on sucrose (10.4 ± 0.9 mmHg) (p < 0.01). A highly significant correlation was found between hepatocyte surface area and intrahepatic pressure (r = 0.70; p < 0.005). There was no increase in collagen in the Disse space in these animals. Therefore, hepatomegaly in the absence of an increase in collagen in the Disse space may result in increased intrahepatic pressure. These studies may indicate a sequence of events: hepatomegaly, portal hypertension, and collagenization in the Disse space, which could occur in alcoholic liver disease.

Changes in the number of insulin receptors of isolated rat hepatocytes during pregnancy and lactation

The weight of the rat liver increased during pregnancy and lactation due solely to an increase in hepatocyte size. Insulin receptors were identified using 125I-labelled insulin and isolated hepatocytes in vitro. Scatchard analysis was interpreted in terms of high affinity ( K D 4 nM) and low affinity ( K D 80 nM ) receptors for insulin. No change in the affinity of either receptor site was detected during pregnancy or lactation. There was, however, a significant increase in the number of both types of receptor on the hepatocyte by day 12 of pregnancy which was maintained until at least day 20 of pregnancy. During lactation, the number of receptors declined to values similar to those of virgin rats. Serum insulin concentrations, determined by radioimmunoassay, were elevated during pregnancy, returned to valued similar to virgin rats during early lactation and were significantly reduced compared with virgin rats by day 15 of lactation. These results illustrate that physiological conditions exist whereby the number of insulin receptors may increase, despite elevated serum insulin concentrations, in apparent conflict with the ‘down-receptor’ hypothesis.

EM Changes and Other Toxic Effects of FireMaster BP-6 (Polybrominated Biphenyls) in the Mouse

Groups of Swiss ICR mice were fed 1000 ppm polybrominated biphenyls (FireMaster BP-6) in rodent chow for 4, 8, 11, and 14 days. Control groups were fed standard rodent chow without FireMaster BP-6. Animals were killed at the end of each feeding period and the livers examined by electron microscopy. EM changes noted were progressive increase in size of hepatocytes, a decrease in rough endoplasmic reticulum, a marked increase in smooth endoplasmic reticulum, mitochondrial degeneration, increased lysosomes, and a decrease in glycogen. In addition, there was increasing proliferation of microvilli in bile canaliculi with increasing feeding times. A group of mice fed 1000 ppm FireMaster BP-6 in rodent chow for 11 days had livers with a mean of 13.93% of total body weight as compared with 6.49% for the control group (P=0.02). Tissue distribution following ingestion of 100 ppm FireMaster BP-6 for 14 days was studied. Twelve weeks post-feeding, the tissue concentrations of hexabromobiphenyl in order of highest concentration to lowest were as follows: perithymic fat, perirenal fat, adrenal glands, thymus gland, liver and stomach.

EM changes and other toxic effects of firemaster BP-6 (polybrominated biphenyls) in the mouse.

Groups of Swiss ICR mice were fed 1000 ppm polybrominated biphenyls (FireMaster BP-6) in rodent chow for 4, 8, 11, and 14 days. Control groups were fed standard rodent chow without FireMaster BP-6. Animals were killed at the end of each feeding period and the livers examined by electron microscopy. EM changes noted were progressive increase in size of hepatocytes, a decrease in rough endoplasmic reticulum, a marked increase in smooth endoplasmic reticulum, mitochondrial degeneration, increased lysosomes, and a decrease in glycogen. In addition, there was increasing proliferation of microvilli in bile canaliculi with increasing feeding times. A group of mice fed 1000 ppm FireMaster BP-6 in rodent chow for 11 days had livers with a mean of 13.93% of total body weight as compared with 6.49% for the control group (P=0.02). Tissue distribution following ingestion of 100 ppm FireMaster BP-6 for 14 days was studied. Twelve weeks post-feeding, the tissue concentrations of hexabromobiphenyl in order of highest concentration to lowest were as follows: perithymic fat, perirenal fat, adrenal glands, thymus gland, liver and stomach.