Hassan I. El-Sayyad

Towards understanding the mode of action of the multifaceted cell adhesion receptor CD146

CD146, also known as melanoma cell adhesion molecule or MCAM, is a key cell adhesion protein in vascular endothelial cell activity and angiogenesis. CD146 promotes tumor progression of many cancers including melanoma and prostate. Strikingly, its expression is frequently lost in breast carcinoma cells, and it may act as a suppressor of breast cancer progression. While upstream mechanisms regulating CD146 are well documented, our understanding of the downstream molecular events underlying its mode of action remains to be elucidated. This review aims to focus on the progress in understanding the signaling mechanisms and the functional relevance of CD146, a multifaceted molecule, in cancer with particular emphasis on its role in inhibiting breast cancer progression.

Effects of fried potato chip supplementation on mouse pregnancy and fetal development

OBJECTIVE Acrylamide (ACR), a proven rodent carcinogen, is present at significantly high quantities in commonly consumed foods such as potato chips, raising a health concern worldwide. METHODS The effects of ACR and fried potato chips (FPC) on pregnant mice and their offspring before and after birth were investigated and compared. RESULTS In the pregnant mice, similar histologic abnormalities were found in various tissues for ACR intoxication and FPC supplementation. Drastic alterations were mainly seen in the liver, kidney, heart muscle, and epiphyseal cartilage of experimental dams. ACR and FPC increased the rate of abortion and neonatal mortality and decreased the total number, body weight, size, and crown-rump length of the offspring before and after birth. Interestingly, however, higher rates of congenital malformations were observed in the FPC-treated group. Although ossification of axial and appendicular bones was markedly retarded during fetal development, some ossified bones were missing in newly born offspring of treated groups. Furthermore, the incidence of missing ossification centers was higher in the FPC-treated than in the ACR-treated neonates. CONCLUSION These results suggest that FPC can cause hazardous health effects and warrant a systematic study on the health effects of consumption of FPC and French fries in the general population.

Structural and ultrastructural evidence of neurotoxic effects of fried potato chips on rat postnatal development.

OBJECTIVE Acrylamide (ACR), a proved rodent carcinogen and neurotoxic agent, is present in significant quantities in commonly consumed foods such as fried potato chips (FPC) and French fries, raising a health concern worldwide. We investigated and compared the neurotoxic effects of ACR and FPC on postnatal development. METHODS Female rats were treated with ACR (30 mg/kg of body weight), fed a diet containing approximately 30% of FPC during pregnancy, or fed a standard diet (control) and their offspring were examined. RESULTS Female rats treated with ACR or fed a diet containing FPC during pregnancy gave birth to litters with delayed growth and decreased body and brain weights. Light microscopic studies of the cerebellar cortex of treated animals revealed drastic decreases in Purkinje cells and internal granular layers. Different patterns of cell death were detected in Purkinje cells and neurons in the brains of pups born to treated mothers. Ultrastructural analysis of Purkinje cells revealed changes in the endoplasmic reticulum, loss of the normal arrangement of polyribosomes, swollen mitochondria with abnormally differentiated cristae, and an abnormal Golgi apparatus. The gastrocnemius muscle in the ACR and FPC groups showed extensive degeneration of myofibrils as evidenced by poorly differentiated A, H, and Z bands. CONCLUSION The present study reveals for the first time that rat fetal exposure to ACR, as a pure compound or from a maternal diet of FPC, causes cerebellar cortical defects and myodegeneration of the gastrocnemius muscle during the postnatal development of pups. These results warrant a systematic study of the health effects of the consumption of FPC and French fries in the general population.

Biochemical characterization of riboflavin carrier protein (RCP) in prostate cancer

Riboflavin carrier protein (RCP) is a growth- and development-specific protein. Here, we characterized the expression of this protein in prostate cancer by polyclonal and monoclonal antibodies against chicken RCP. RCP was localized to both androgen-dependent and independent prostate cancer cell lines. Compared to controls, RCP was over-expressed in all 45 prostate adenocarcinomas, irrespective of the Gleasons score or the stage of the disease. The identified RCP had a molecular weight of 38 kDa, similar to RCP purified from chicken. Presence of this protein was also confirmed by siRNA inhibition analysis. Antibodies to chicken RCP inhibited incorporation of tritiated thymidine into DNA and prevented riboflavin uptake in PC3 prostate cancer cells, suggesting a critical function of this protein in prostate cancer cell growth. These data suggest that RCP can be used as a tumor biomarker in prostate cancer.

Hazardous effects of fried potato chips on the development of retina in albino rats.

OBJECTIVE To evaluate the hazardous effects of fried potato chips upon the retina of two developmental stages of the albino rats aged 7 and 14 days from parturition. METHODS PREGNANT RATS WERE ARRANGED INTO TWO GROUPS: control pregnant rats and consequently their delivered newborns until reaching 7 and 14 days old from parturition and fried potato chips group in which pregnant rats at the 6th day of gestation maintained on diet formed of fried potato chips supplied from the market mixed with standard diet at a concentration of 50% per each till 7 and 14 post-partum. Three fold integrated approaches were adopted, namely, histological, ultrastructural and proteomic analysis. RESULTS Histological examination of the retina of the experimental offsprings revealed many histopathological changes, including massive degeneration, vacuolization and cell loss in the ganglion cell layer, as well as general reduction in retinal size. At the ultrastructural level, the retina of experimental offsprings exhibited number of deformities, including ill differentiated and degenerated nuclear layer, malformed and vacuolated pigment epithelium with vesiculated and fragmented rough endoplasmic reticulum, degenerated outer segment of photoreceptors, as well as swollen choriocapillaris and loss of neuronal cells. Proteomic analysis of retina of the two experimental developmental stages showed variations in the expressed proteins as a result of intoxication which illustrated the adverse toxic effects of fried potato chips upon the retina. CONCLUSIONS It can be concluded that the effect of fried potato chips on the development of retina in rats may be due to the presence of acrylamide or its metabolite.

Cholesterol overload impairing cerebellar function: The promise of natural products

The cerebellum is the part of the brain most involved in controlling motor and cognitive function. The surface becomes convoluted, forming folia that have a characteristic internal structure of three layers including molecular, Purkinje cell, and granular layer. This complex neural network gives rise to a massive signal-processing capability. Cholesterol is a major constituent, derived by de novo synthesis and the blood-brain barrier. Cholesterol is tightly regulated between neurons and glia-that is, astrocytes, microglia, and oligodendrocytes-and is essential for normal brain development. The axon is wrapped by myelin (cholesterol, phospholipids, and glycosphingolipids) and made up of membranes of oligodendrocytes, separated by periodic gaps in the myelin sheath, called nodes of Ranvier. Hypercholesterolemia is associated with increased oxidative stress and the development of neurotoxicity and Alzheimers disease. Treatment with natural products has been found to support improved brain function and reduce low-density-lipoprotein cholesterol level. Fish oil is one such product; among the many plant products are: Morus alba leaves, fruit, and bark; pomegranate fruit and peel; Barley β - glucans; date palm; and Allium sativum. The therapeutic potential was discussed in relation with the antilipidemic drugs, statins (HMG-CoA reductase inhibitors).

Effect of maternal diabetes and hypercholesterolemia on fetal liver of albino Wistar rats

OBJECTIVE The aim of this study was to predict the development of hepatic lesions and impairment of function during the development of fetuses (13-, 15-, 17-, and 19-d-old embryos) of diabetic and hypercholesterolemic mothers. METHODS Eighty virgin and fertile male rats (one male/three females) of Wistar strain with an average body weight of 150 to 180 g were used. Mating was carried out, and pregnancy was determined by examining sperm in vaginal smears. Pregnant rats were arranged into three groups; control, diabetic (single intraperitoneal injection [i.p.] of 60 mg streptozotocin/kg) and hypercholesterolemic groups (fed on a diet containing 3% cholesterol for 6 wk before conception and throughout gestation) (n = 20). Pregnant rats were sacrificed and 13-, 15-, 17-, and 19-d-old embryos and livers were incised and subjected to histological and transmission electronic microscopical (TEM) investigations, assessments of alkaline phosphatase (Al-Pase) isoenzymes electrophoresis, DNA fragmentation, and comet assay. Flow cytometric analysis of apoptosis and caspases 3 and 9 in the livers of mother rats and their 19-d-old fetuses was determined. RESULTS Histologic findings of diabetic and hypercholesterolemic mothers revealed apparent damage of hepatocytes, accumulation of lipid-laden cells, and vascular steatosis, while the 13-, 15-, 17- or 19-d-old fetuses of either diabetic or hypercholesterolemic mothers revealed disorganized hepatic architecture and massive cell damage. TEM of diseased mothers and their fetuses possessed increased incidence of pyknotic hepatocytes with massive vesicuolation of rough endoplasmic reticulum and degeneration of mitochondria. Al-Pase isoenzymes were altered and genomic DNA of both double and single helical structures were markedly damaged, especially in fetuses of maternally diabetic and hypercholesterolemic mothers. Flow cytometry revealed an increase in apoptosis and caspases 3 and 9 in diabetic and hypercholesterolemic mothers and their 19-d-old fetuses. CONCLUSION These results suggested that maternal diabetes and hypercholesterolemia predicted early hepatitis and increased apoptosis in mothers and their fetuses as a result of oxidative stress and elevated apoptic markers caspases 3 and 9.

Studies on Tongue of Reptilian Species Psammophis sibilans, Tarentola annularis and Crocodylus niloticus

En el presente estudio fueron utilizados tres diferentes especies de reptiles Psammophis sibilans (Orden Ophidia), Tarentola annularis (Orden Squamata y Crocodylus niloticus (Orden Crocodylia). Sus lenguas fueron removidas y examinadas morfologicamente. Las mucosas linguales se examinaron bajo microscopio electronico de barrido (SEM) y tambien procesadas para la investigacion histologica. El estudio morfologico macroscopico revelo variaciones de la estructura de la lengua, siendo estas alargadas con el extremo bifurcado en P. sibilans o de estructura triangular aplanada con una base amplia y el borde libre conico en T. annularis o triangular rugosa llenando casi todo el suelo de la cavidad en C. niloticus. En el SEM, la mucosa lingual mostro finas ranuras estriadas dispuestas radialmente en la extension oblicua con perdida de las papilas linguales. Numerosas microcrestas fueron detectadas por encima de la superficie de las celulas en P. sibilans. T. annularis exhibiendo una disposicion de papilas filiformes conicas aplanadas y abundante de microcrestas. Sin embargo, en C. niloticus, la mucosa lingual posee diferentes tipos de papilas filiformes ademas de papilas gustativas con una extensa disposicion de corpusculos gustativas. Histologicamente, mediante confirmacion de SEM se ilustra la protrusion del epitelio escamoso estratificado de la mucosa lingual en P. sibilans y la presencia de corpusculos gustativos apicales en las papilas filiformes conicas de T. annularis. La mucosa lingual de C. niloticus revelo diferentes formas de ambas papilas, filiformes y gustativas.

Analysis of fine structure and biochemical changes of retina during aging of Wistar albino rats

Aging is a biological phenomenon that involves an increase of oxidative stress associated with gradual degradation of the structure and function of the retina. Gender differences and subsequent deterioration of retinal cell layers is an interesting topic, especially because there is no published work concerning it.

Hypercholesterolemia-induced ocular disorder: Ameliorating role of phytotherapy

The ocular region is a complex structure that allows conscious light perception and vision. It is of ecto-mesodermal origin. Cholesterol and polyunsaturated fatty acids are involved in retinal cell function; however, hypercholesterolemia and diabetes impair its function. Retinal damage, neovascularization, and cataracts are the main complications of cholesterol overload. Dietary supplementation of selected plant products can lead to the scavenging of free reactive oxygen species, thereby protecting the ocular regions from the damage of hypercholesterolemia. This review illustrates the dramatic effects of increased cholesterol levels on the ocular regions. The effect of phytotherapy is discussed in relation to the different regions of the eye, including the retina, cornea, and lens.