Manal R. Abd El-Haleem

Effects of Exposure to Plasticizers Di-(2-Ethylhexyl) Phthalate and Trioctyltrimellitate on the Histological Structure of Adult Male Albino Rats Liver

Di (2-ethylhexyl) phthalate (DEHP) and Trioctyltrimellitate (TOTM) are plasticizers used to increase the flexibility of polyvinyl chloride. Their wide commercial usage carries high risk of human exposure. This work aimed to investigate histological changes of rat’s liver upon DEHP and TOTM exposure. 36 adult male albino rats were classified into 3 equal groups; control group, group II (given DEHP 300 mg/kg) and Group III (given TOTM 300 mg/ kg) orally for 4 weeks. Half of the animals were sacrificed after one day of last dose (subgroups IIA & IIIA) and the remaining were left for another 4 weeks for recovery (subgroups IIB & IIIB). Liver specimens were examined by light and electron microscopes and immunohistochemical stain for hepatocyte paraffin -1 (Hep Par-1). By examination of subgroup IIA all rats’ liver showed focal changes. Dramatically affected lobules revealed loss of lobular architecture with periportal cellular and fatty infiltrations. Hepatocytes had shrunken nuclei, peroxisomes and lipid globules. Subgroup IIB showed mild morphological improvement. Subgroup IIIA showed preserved lobular architecture with vascular congestion. Hepatocytes showed euchromatic nuclei and lipid globules. Subgroup IIIB revealed apparent normal lobular architecture and normal hepatocytes. Comparing to control group, the area % of Hep Par-1 immune reaction in subgroup IIA was highly significant decrease while group IIB was significantly decreased. Subgroup IIIA was significantly decreased. However, group IIIB had no significant difference with control. In conclusion, DEHP induced serious changes on liver; most of these changes were irreversible. TOTM has mild reversible effects. It is recommended to use safely as an alternative plasticizer.

Comparing the effects of MSCs and CD34+ cell therapy in a rat model of myocardial infarction

Stem cell therapy is considered as a promising approach in the treatment of myocardial infarction (MI). This study was designed as a comparison of human umbilical cord blood (HUCB)‐derived CD34+ and HUCB‐derived MSCs for the repair of cardiac tissue by induction of the angiogenesis. Forty‐eight male rats were randomized into four groups: sham‐operated group, MI group, MSCs‐treated group, and CD34+ cells‐treated group. After 4 weeks, the rats were sacrificed. All sections from left ventricles of all groups were subjected to hematoxylin & eosin, Massons trichrome, and immunohistochemical stains (CD133, CD44, and α‐smooth muscle actin). RNA was extracted for gene expression of the angiogenic markers. A significant reduction of the infarct size and the amplitude of T‐wave in the CD34+ cells‐treated group when compared with the MSCs‐treated group were determined. Histologically, the MI group showed scar tissue, congested blood capillaries around the infarcted area, some necrotic cells, and inflammatory cells. Administration of either MSCs or CD34+ cells had a therapeutic potential to induce regenerative changes in the myocardium with better results in CD34+cells‐treated group. Quantitative RT‐PCR analysis revealed a significant increase in the expression of vascular endothelial growth factor (VEGF), VEGFR‐2, Ang‐1, and Tie‐2 and a significant decreased expression of Ang‐2 in stem cells transplanted groups when compared with the noncell transplanted hearts. A significant increase of VEGF, VEGFR‐2, Ang‐1, and Tie‐2 expression in the group receiving CD34+ cells than those receiving MSCs was found. Finally, there was an upregulation of both human VEGF and human hypoxia‐inducible factor 1α in the infarcted hearts treated by CD34+ cells than that treated by MSCs. We first revealed a superior efficacy of CD34+ cells when compared with MSCs in induction of regenerative changes in the MI model. Both cell therapies may repair the damaged heart tissue primarily by secretion of proangiogenic factors that induce the angiogenesis and activate the angiogenesis signaling pathway.

Anti-oxidative and anti-apoptotic roles of spermatogonial stem cells in reversing cisplatin-induced testicular toxicity

BACKGROUND AIMS Because of reproductive toxic effects of chemotherapy, researchers have taken some techniques to preserve fertility potential. The present study was designed to point out the potential role of spermatogonial stem cell (SSC) therapy in reversing cisplatin (CP)-induced testicular toxicity and restore the spermatogenesis. METHODS Sixty rats were randomly divided into three groups: group 1, control group; group 2, rats received CP in a dose of 7 mg/kg/day for 5 consecutive days; group 3, CP was injected at 7 mg/kg per day for 5 consecutive days, and, on the 6th day of the experiment, rats were treated with SSC. Forty days after receiving the last dose of CP, rats were euthanized under anesthesia; testes were collected, and gene expression using real-time polymerase chain reaction for P53, Bax, caspase 9 and cytochrome c, testicular histological findings and oxidative status were determined. RESULTS Administration of cisplatin caused significant increases in malondialdehyde levels, Bax and caspase 9 genes expression levels concomitant with significant decreases in anti-oxidant enzyme activities, p53 and cytochrome c gene expression levels, along with some histopathological lesions in testicular tissue. SCC attenuated the disturbance in oxidant/anti-oxidant status and testicular apoptosis; this is associated with improvements in the histopathological view of the testicular tissue. CONCLUSIONS The current study highlights evidence that the SCC has anti-oxidative and anti-apoptotic properties that could reverse CP-induced testicular toxicity, in addition to their role in spermatogenesis.

Effect of sodium fluoride on the thyroid gland of growing male albino rats: histological and biochemical study

Introduction Sodium fluoride (Na–F) is commonly added to drinking water and decay-preventive ingredients. Long-term exposure to Na–F leads to some adverse effects on various organs. Its structural shape is similar to iodine, with a considerable potential to cause thyroid gland dysfunction. Aim of the work The aim of the present work was to study the possible histological and biochemical changes induced by chronic Na–F exposure on the thyroid gland. Materials and methods Twenty male rats (30 days, 40–45 g) were equally divided into two groups. Group I served as a control and group II included rats that received 11 mg/kg/day Na–F orally by a gastric tube for 120 days. At the end of the experiment, rats were sacrificed after ether inhalation and blood samples were subjected to a hormonal assay of T3, T4, and thyroid-stimulating hormone (TSH) levels in addition to superoxide dismutase (SOD) and malondialdehyde (MDA). The thyroid gland tissue samples were processed for light and electron microscopic examination. Also, an immunohistochemical study was carried out for the detection of parafollicular or C cells. The results obtained were analyzed morphometrically and statistically. Results Histological examination of the thyroid follicles in the Na–F-treated rats showed different changes. Some follicles showed signs of degeneration in the form of a decrease in area % of colloid and fusion of the follicles; also, the follicular cells showed irregular dilation of rough endoplasmic reticulum, cytoplasmic vacuolation, and irregular nuclei. Other follicles showed signs of hyperactivity manifested by the presence of microfollicles, follicular epithelial cell stratification, and extensive vacuolated colloid, with an increase in the number of lysosomes. Also, hyperplasia was observed in parafollicular cells and confirmed statistically. Alterations in the thyroid structure were further confirmed by the results of the hormonal assay, which showed a significant and a highly significant decrease in serum T4 and T3, respectively, with a subsequent increase in TSH. The MDA activity increased significantly, whereas the SOD content decreased. Conclusion Our study showed that long-term low-dose exposure to Na–F affects the thyroid structure and function, leading to hypothyroidism. It can also be concluded that a mutual cooperation exists between the follicular and the C cells.

Effect of experimentally induced portal hypertension on the fundic mucosa of adult male albino rats and the possible protective role of quercetin supplementation: histological, immunohistochemical, and biochemical study

Introduction Portal hypertension (PHT) is a hyperdynamic circulation disorder. Its precise effect on the fundic mucosa remains a matter of controversy. Aim of study Evaluation of the effect of long –term experimental induction of PHT on the rat fundic mucosa and the possible protective role of quercetin. Materials and methods Forty rats were divided into the following three main groups; control, partial portal vein ligation (PPVL) and PPVL receiving 50 mg/kg/day of quercetin given intraperitoneal. After ten weeks from PPVL induction, samples from fundus of stomach were prepared for light and electron microscope. Tissue and blood samples were examined for inflammatory, oxidative stress and antioxidant markers. The number of parietal cells, area % of collagen fibers, PAS –alcian blue reaction, nitrotyrosine- and caspase-3 positive reaction were measured morphometrically and statistically analyzed. Results Fundic mucosa of PPVL group showed loss of normal architecture, exfoliation of the surface epithelium, inflammatory cellular infiltration and congestion of blood vessels in lamina propria. Parietal cells showed dilatation of their intracellular canaliculi. Many mucous cells had apoptotic nuclei. Chief cells had few secretory granules and dilated RER. Statistically, there was significant increase in the area% of collagen fibers, nitrotyrosine, caspase- 3 and inflammatory markers while area% of PAS–alcian blue reaction, number of parietal cells and tissue antioxidant enzymes showed significant reduction comparing with the control. Quercetin markedly protect fundic mucosa from histological and biochemical deleterious effects of PHT. Conclusion PHT exerts a deleterious histological and biochemical effects on the fundic mucosa. Both antioxidant and antiinflammatory effects of Quercetin offer degree of protection for fundic mucosa, therefore, it may protect from gastropathy resulted from PHT.

Bone marrow–derived mesenchymal stem cells ameliorate parotid injury in ovariectomized rats

BACKGROUND AIMS Parotid hypofunction causes life-disrupting effects, and there are no effective medications for xerostomia. We hypothesized that mesenchymal stem cells (MSCs) have repairing effects on parotid glands of ovariectomized (OVX) rats. METHODS Forty-five adult female rats were divided into three equal groups: group I (Control group), group II (OVX-group) and group III (OVX rats that received MSCs at 4 and 8 weeks post-ovariectomy). At 12 weeks post-ovariectomy, histological (Massons trichrome and periodic acid-Schiff with alcian blue stains), immunohistochemical (caspase-3 and CD44) and morphometric studies and salivary flow rate and saliva pH determination were carried out. RESULTS Histologically, the OVX group displayed numerous irregular vacuolated acini, thickened septa with marked cellular infiltration and vascular congestion. Degenerated organelles and few or irregular secretory granules with a different density were observed. Caspase-3-positive cells were highly expressed. MSC-treated glands exhibited a considerable degree of preservation of glandular architecture with numerous CD44-expressing and few caspase-3-expressing cells. Significant decrease of the salivary flow rate in the OVX group was detected, which reverted to normal levels in group III. CONCLUSIONS MSCs ameliorated the damaging effects of ovariectomy on the parotid glands.

The ability of hesperidin compared to that of insulin for preventing osteoporosis induced by type I diabetes in young male albino rats: A histological and biochemical study

BACKGROUND Patients with type I diabetes are at increased risk of osteoporosis even after insulin therapy in adult stage. This study was conducted to compare the efficacy of hesperidin (hesp) therapy versus that of insulin alone in the alleviation of osteoporosis arising from type I diabetes mellitus (T1DM) in young rats. MATERIALS AND METHODS Hesperidin was administered orally to STZ-induced diabetes. The animals were evaluated morphologically and biochemically and compared with that received daily SC injections of long-acting insulin. RESULTS Histologically, we observed the degeneration of osteoblasts and osteocytes, decreased collagen fibers, and disturbed bone turn over markers in untreated DM rats. Hesperidin+ insulin supplementation to diabetic rats caused significant improvement of most of the bone histological and morphometric parameters compared with the insulin-treated group. Furthermore, hesp treatment significantly reduced pro-inflammatory mediators TNFα and NF-κB and increased serum biochemical markers of bone turnover, including osteopontin (OPN), osteocalcin (OC) and decreased serum alkaline phosphatase (ALP). CONCLUSION These data demonstrated that hesp could be considered to be a beneficial drug for preventing diabetic osteoporosis in growing age.

Epithelial and stromal alterations in prostate after cypermethrin administration in adult albino rats (histological and biochemical study).

Histological and biochemical alterations induced in prostate by cypermethrin insecticide exposure were investigated in adult albino rats. 60 mg/kg/day of cypermethrin were given orally to experimental group for 15 days then prostatic specimens were processed for light and electron microscopic examinations and for assessment of oxidative stress markers; prostatic glutathione (GSH), glutathione peroxidase enzyme (GPx) and malondialdehyde (MDA). Massons trichrome and anti-α-actin antibodies immunohistochemical staining were done. Blood samples were collected for measurement of total and prostatic acid phosphatase enzymes. Morphometric and statistical analyses were conducted. Cypermethrin treated group showed decrease in acinar epithelial height with detection of heterochromatic nuclei, cytoplasmic vacuolations and few apical microvilli. The stroma surrounding the acini was widened with significant increase in collagen fibers and significant decrease in smooth muscle cell α-actin immunoexpression. This was accompanied by a significant decrease of prostatic GSH level, activity of GPx enzyme with a significant increase in MDA level. Significant decrease in total and prostatic enzyme activities was also detected. In conclusion, cypermethrin induced epithelial degenerative changes in prostate which were accompanied by stromal alterations that seemed to be due to oxidative stress. More attention is required to the role of stromal microenvironment and oxidative stress markers in prostatic diseases.

The structure of the optic nerve after the administration of interferon α-2a in adult male albino rats and the role of α-lipoic acid supplementation

IntroductionInterferon alpha (IFN-&agr;) therapy is used considerably in Egypt because of a high prevalence rate of chronic hepatitis C virus infection. &agr;-Lipoic acid (ALA) has been found to play a neuroprotective role in many insults. The aim of this study is to observe the histological structure of the optic nerve of rats after an injection of IFN-&agr; and to determine the role of ALA supplementation. Materials and methodsForty adult male albino rats were divided equally into four groups. Group I served as the control group. Group II included rats that received ALA alone (100mg/kg/day, intraperitoneally). Group III included rats that received IFN-&agr; alone (100000 IU/kg/three times/week, intraperitoneally). Group IV included rats that received both IFN-&agr; and ALA. After 8 weeks, the optic nerves were extirpated and processed for light and electron microscope examination. ResultsOptic nerves of the group that received IFN-&agr; showed nerve damage manifested as axonal damage and changes in the myelin sheath. Neuroglia showed vacuolation in their cytoplasm and heterochromatic nuclei. Morphometric and statistical analyses showed a significant increase in the surface area of positive glial fibrillary acidic protein astrocytes, indicating reactive astrogliosis. Blood capillaries were distorted with ill-defined walls and protrusion of the endothelial cells into their lumina. These changes were limited by concomitant ALA supplementation with IFN-&agr;. ConclusionIFN-&agr; exerted a deleterious effect on the histological structure of the optic nerve in rats and ALA supplementation minimized these effects.

Pomegranate protective effect on experimental ischemia/reperfusion retinal injury in rats (histological and biochemical study)

ABSTRACT Oxidative stress is one mechanism involved in the pathogenesis of ischemia/reperfusion (/R) retinal injury. The histological, biochemical, and functional changes associated with pomegranate (PMG) treatment prior to retinal I/R were analyzed using 40 adult male albino rats. Rats were divided into four groups: Groups I and II (sham operated and received saline or PMG, respectively); Groups III and IV (I/R rat models with prior administration of saline or 250 mg/kg/day PMG, respectively). Electroretinogram (ERG) results were recorded and eye specimens were taken and processed for light and electron microscopic examinations and for assessment of oxidative status in retinal homogenate. I/R lead to degenerative changes in retinal layers with a significant reduction in nuclear factor erythroid 2-related factor 2 (Nrf2) immunoreactivity in concomitant with significant oxidant–antioxidant disturbance and decreased a- and b-wave amplitude in the ERG. These alterations were ameliorated with prior PMG treatment. In conclusion, PMG treatment, as an antioxidant, attenuated retinal structural and functional I/R injury through activation of Nrf2 which could be a base for future therapy designs.