Bunyami Unal

The effects of high-fat diet on the renal structure and morphometric parametric of kidneys in rats

To characterize the kidney in a high‐fat‐induced obesity model, we examined the renal structure of adult Sprague–Dawley rats fed a control diet or a high‐fat diet for 3 months. Ten adult female Sprague–Dawley rats were fed a diet consisting highly of fat (30%) for a period of 3 months. Ten control rats were maintained with standard rat chow. All animals were weighed every 10 days for 3 months. At the end of the experiment, the naso‐anal length of the anaesthetized rats was measured to calculate body mass index, and subsequently whole kidneys of intracardially formalin‐perfused animals were removed. Quantitative features of the kidney were analysed with the Cavalieri and physical dissector methods applied to serial paraffin sections. Kidney samples were also examined histologically. The body mass indices of the control and treatment groups were 4.528 ± 0.242 and 5.876 ± 0.318 kg m−2, respectively. The difference between the body mass indices of the two groups was statistically significant (P < 0.01, Mann–Whitney U‐test), suggesting that the animals fed with a high‐fat diet may be overweight. Stereological examination of the kidneys revealed differences in kidney weight, total kidney volume, volume of cortex, medulla, glomeruli, proximal and distal tubules, and numerical density of glomeruli and glomerular height in the treatment group compared with the control group. Light microscopic investigation showed a dilatation in blood vessels and Bowmans space, mononuclear cell infiltration, degeneration in nephrons, including glomerulosclerosis and tubular defects, and an increase in the connective tissue in the kidneys in the treatment group. We concluded that a fatty diet is responsible for the rats’ obesity and may lead to renal deformities as a result of histopathological changes such as dilatation, tubular defects, inflammation and connective tissue enlargement of the kidney.

Spirulina platensis feeding inhibited the anemia- and leucopenia-induced lead and cadmium in rats

In the present investigation, the effect of Spirulina platensis (Sp) was undertaken on rats fed with lead and cadmium including diet by using physiological, enzymehistochemical and stereological methods. For this aim, 50 rats were equally divided into five groups as control (C), lead (Pb), Spirulina+lead (Sp+Pb), cadmium (Cd), and Spirulina+cadmium (Sp+Cd). Red blood cell (RBC) and white blood cell (WBC) counts, packed cell volume (PCV), and haemoglobine (Hb) concentrations were determined by haemocytometric methods in blood samples collected on 30th day. Population of T lymphocyte was counted by the alpha-naphthyl acetate esterase (ANAE) staining method, and reticulocytes were counted by stereological method. The counts of RBC, WBC, and ANAE positive T lymphocyte, and the values of Hb, PCV, and MCHC were decreased in the Pb and Cd groups compared to control group. Also, the number of reticulocytes (polychromatofilic erythrocyte) increased in the Pb groups, whereas it decreased in the Cd group. On the other hand, these values were ceased by S. platensis in the treated groups. These results suggest that S. platensis supplementation may be useful in adjuvant treatment of leukemia and anemia caused by lead and cadmium toxication.

Alpha-lipoic acid as a potential target for the treatment of lung injury caused by cecal ligation and puncture-induced sepsis model in rats.

One of the common lethal complications of septic shock, a major cause of morbidity and mortality in patients with severe trauma and so on, is acute lung injury. &agr;-Lipoic acid (ALA), with antioxidant properties, is a popular agent. Thus, we investigated the potential protective effects of ALA (200 mg/kg) on sepsis-induced acute lung injury. Rats were exposed to cecal ligation and puncture (CLP) to induce sepsis. Rat groups were designed as (a) sham operated, (b) sham operated + ALA treated, (c) CLP applied, (d) CLP + ALA treated. Sixteen hours after CLP induction, serum samples and lung tissues were obtained for biochemical and histopathological examination. &agr;-Lipoic acid decreased the serum levels of inflammatory cytokines such as TNF-&agr; and IL-6, which increased after CLP. Increased activity of nuclear factor &kgr;B in septic lung tissues was decreased by ALA. &agr;-Lipoic acid improved the decreased antioxidant activity and alleviated the increased oxidant activity, which occurred after CLP application. We can suggest that ALA showed beneficial effects by decreasing nuclear factor &kgr;B activation in lung tissues, resulting in decreased serum levels of TNF-&agr; and IL-6, and also increasing the antioxidant capacity of the lungs.

Protective effects of montelukast on ischemia-reperfusion injury in rat ovaries subjected to torsion and detorsion: biochemical and histopathologic evaluation

OBJECTIVE To reveal the effects of montelukast as an antioxidant and tissue protective agent and study the biochemical and histopathologic changes in experimental ischemia and ischemia-reperfusion (I/R) injury in rat ovaries. DESIGN Experimental study. SETTING Experimental surgery laboratory in a university department. ANIMAL(S) Forty-eight rats with experimentally induced ovarian torsion. INTERVENTION(S) Group 1: sham; Group 2: ovarian ischemia; Group 3: a 30-hour period of ischemia followed by a 3-hour reperfusion. Groups 4 and 5: rats administered 10 and 20 mg/kg doses of montelukast before a half-hour of ischemia, then ovarian ischemia applied; after a 3-hour period of ischemia, the bilateral ovaries removed. Groups 6 and 7: 3-hour period of ovarian ischemia applied, then 2.5 hours after the ischemia induction, rats given montelukast. Group 8: sham operation and 20 mg/kg of montelukast; at the end of a 3-hour period of ischemia, 3-hours of reperfusion continued. MAIN OUTCOME MEASURE(S) Measurement of ovarian tissue concentrations of superoxide dismutase (SOD), glutathione (GSH), lipid peroxidation (LPO) and myeloperoxidase (MPO) activity; and histopathologic examination of all ovarian rat tissue. RESULT(S) Montelukast treatment normalized changes of LPO and MPO and stimulated an overproduction of endogenous SOD and GSH. The results of the histologic parameters showed that treatment with montelukast in the I/R group of rats ameliorated the development of ischemia and reperfusion tissue injury. CONCLUSION(S) Montelukast at different doses attenuates ovarian I/R-induced ovary tissue injury in rats.

The significance of immunohistochemistry in the skin pathergy reaction of patients with Behçet's syndrome.

Background  Behçets syndrome is a chronic systemic immuno‐inflammatory disorder affecting multiple organs with generalized vasculitis of arteries and veins. Although the aetiology is still unknown, endothelial dysfunction is one of the most prominent features in Behçets syndrome. The skin pathergy reaction (SPR) is a non‐specific hyperreactive lesion formation that is one of the major features and diagnostic criteria of the disease. It develops after 24–48 h at the site of the needle‐prick, especially in the exacerbation period, and it is very similar to the erythematous papules or pustules that appear spontaneously in patients with Behçets syndrome. Therefore, an investigation into the formation of the SPR lesion may contribute to the pathophysiology of skin lesions of this unique disorder.

A simple technique for localizing consecutive fields for disector pairs in light microscopy: Application to neuron counting in rabbit spinal cord following spinal cord injury

Locating the same microscopic fields in consecutive sections is important in stereological analysis. The tools for achieving this requirement have limited number in practice. This paper presents a simple and inexpensive technique for localizing the same fields on disector pairs in conventional light microscopes equipped with widely available dial indicators. It is partly a modification of equipment previously described. The presented procedure requires two light microscopes equipped with dial indicators and modified slide clips. An application of the present system was shown in a model of spinal cord injury (SCI). A midthoracic laminectomy was performed leaving the dura intact. A contusion was done at the level of midthoracic spinal cord segments (T7-T8) by dropping a 10-g mass from a height of 30 cm. The subjects were randomly divided into three groups (10 animals in each): hypothermia group, methylprednisolone group, and traumatic spinal cord injury alone group. Present results show that treatment with hypothermia after spinal cord trauma has a neuroprotective effect on cell damage but not in the methylprednisolone treatment group.

Growth hormone reduces tissue damage in rat ovaries subjected to torsion and detorsion: biochemical and histopathologic evaluation

OBJECTIVE To evaluate the effects of growth hormone (GH) as an antioxidant and tissue-protective agent and analyse the biochemical and histopathological changes in rat ovaries due to experimental ischemia and ischemia/reperfusion injury. STUDY DESIGN Forty-eight adult female rats were randomly divided into eight groups. In Group 1, a period of bilateral ovarian ischemia was applied. In Groups 2 and 3, 1 and 2 mg/kg of GH was administered, and 30 min later, bilateral ovarian ischemia was applied (after a 3-h period of ischemia, both ovaries were surgically removed). Group 4 received a 3-h period of ischemia followed by 3h of reperfusion. Groups 5 and 6 received 1 and 2 mg/kg of GH, respectively, 2.5 h after the induction of ischemia. At the end of a 3-h period of ischemia, bilateral vascular clips were removed, and 3h of reperfusion continued. Group 7 received a sham operation plus 2mg/kg of GH. Group 8 received a sham operation only. After the experiments, superoxide dismutase and myeloperoxidase activity and levels of glutathione and lipid peroxidation were determined, and histopathological changes were examined in all rat ovarian tissue. RESULTS Ischemia and ischemia/reperfusion decreased superoxide dismutase activity and glutathione levels in ovarian tissue, but increased lipid peroxidation levels and myeloperoxidase activity significantly in comparison to the sham group. The 1 and 2 mg/kg doses of GH before ischemia and ischemia/reperfusion decreased lipid peroxidation levels and myeloperoxidase activity in the experimental groups. The administration of GH before ischemia and ischemia/reperfusion treatments also increased superoxide dismutase and glutathione levels. The histopathological findings also suggested a protective role of GH in ischemia/reperfusion injury. That is, ovarian tissues in the ischemia groups showed histopathological changes, such as haemorrhage, cell degeneration, and necrotic and apoptotic cells, but these changes in the GH groups were lesser. Moreover, in the ischemia/reperfusion groups, acute inflammatory processes--such as neutrophil adhesion and migration, apoptotic and degenerative cells, stromal oedema and haemorrhage--were present. However, the ovarian tissues of the IR+GH (1 mg) group had minimal apoptotic cells, and the IR+GH (2 mg) group had no apoptotic cells. In addition, the general ovarian histological structures of these groups were similar to those of the healthy control group. CONCLUSIONS The administration of GH is protective against ischemia and/or ischemia/reperfusion-induced ovarian damage. This protective effect can be attributed to the antioxidant properties of GH.

Does telmisartan prevent hepatic fibrosis in rats with alloxan-induced diabetes?

BACKGROUND/AIMS This study evaluated the effect of telmisartan on the livers of diabetic rats and also aimed to determine the hepatic distribution and role of transforming growth factor beta (TGF-beta) in diabetes-related hepatic degeneration while taking into account the possible protective effects of telmisartan. METHODS Fifteen adult male rats were used and divided into three groups: the non-diabetic healthy group, alloxan-induced diabetic control group, and the alloxan-induced diabetic telmisartan group. The non-diabetic healthy group and the diabetic control group were exposed to saline for 30 days, while the group treated with diabetic drugs was orally administered telmisartan for 30 days (10 mg/kg/day). At the end of the experiment, the rats were sacrificed and the livers were dissected and transferred into the fixation solution. The livers were then evaluated using stereological and histopathological methods. RESULTS Our study of the numerical density of hepatocytes shows a significant difference between the diabetic control group and diabetic rats treated with telmisartan. Immunohistochemical staining for TGF-beta in liver sections of the diabetic rats treated with telmisartan showed no immunoreactivity. The diabetic control group was determined to be strongly immunoreactive to TGF-beta. CONCLUSION Results suggest that telmisartan may reduce type-I diabetes mellitus-induced hepatic injury by suppressing activated hepatic stellate cells through concomitant TGF-beta1 down-regulation.

Effect of a High Fat Diet on Quantitative Features of Adipocytes in the Omentum: An Experimental, Stereological and Ultrastructural Study

Background: Omental adipose tissue specimens of female rats that were fed a high fat (HF) diet were evaluated stereologically and histopathologically. To our knowledge, there is no stereological study on numerical density, nuclear height and volume of adipocytes in omental adipose tissue in the female rat fed a HF diet in the literature. Method: 20 female Spraque Dawley rats were used in the study. 10 of the animals were fed HF diet consisting of 30% of calories from fat for 3 months. The remaining 10 rats, the control group, were fed a normal diet. After the experimental procedure, all animals were anesthetized and omental adipose tissues in the same area were dissected and fixed for the histochemical process using a mixture of 3% glutaraldehyde and 1% osmium tetraoxide in 0.1 M phosphate buffer. After embedding of tissues in araldite CY 212, semi-thin and thin sections were cut. The semi-thin sections were stained with toluidine blue. The physical dissector counting method was used for estimation of numerical density and nuclear height of adipocytes. Cavalieri principle was used for the estimation of adipocyte volume; volume fraction approach was applied to find the volume fraction of adipose tissue components. Results: The mean numerical density of adipocytes in the HF diet group was significantly higher than the control. The mean nuclear height of adipocytes was also very high in the HF diet group. The volume fraction of adipose mass was increased whereas the extracellular matrix volume fraction was reduced in the HF diet group compared to the controls. The mean volume of adipocytes in the HF diet group was also significantly higher than in the control group. At the light microscopy level, it was found that adipocytes were enlarged and gaining irregular shape in the HF diet group. Thicker basal lamina and electron dense lipid content were also found in this group at the electron microscopy level. Conclusion: Lipid content and number of adipocytes in the adipose tissue of HF diet rats were higher than in the controls. Thus, HF diet induces increase in body weight via both hypertrophy and hyperplasia of adipocytes.

Morphological alterations produced by zinc deficiency in rat sciatic nerve : A histological, electron microscopic, and stereological study

Zinc (Zn) is an essential trace element for humans and animals. It is required for normal growth, gene expression, wound healing, protein metabolism, immune function, and membrane integrity. In this study, unbiased stereological methods have been used to quantify the effects of Zn deficiency on the sectioned surface area and the number of myelinated axons in the sciatic nerve of rats. Animals were fed a Zn-deficient or Zn-sufficient diet for a period of 4 weeks. At the end of this time, the samples of sciatic nerves were removed from the animals, processed for electron microscopy and embedded in resin. The Zn-deficient group of rats was found to have a lower body weight compared to rats in the control group (P < 0.05). The sectioned surface area of nerve cross-section and myelinated axon number in Zn-deficient rats decreased by 20% and 29%, respectively, compared to the control group. A significant correlation between sectioned surface area and myelinated axon number was also determined. Morphological findings were as follows: on light microscopy, it was determined that certain abnormalities occur specifically in the experimental group, such as collapsed nerve fascicles, irregular profiles of and degeneration in myelin sheaths, and on electron microscopy, extensive myelin damage was seen in Zn-deficient groups compared with control groups. This study suggests that peripheral nerves require Zn for development and preservation of their structure.