This book reveals some details of research done at Marshall University, USA, involving functional... more This book reveals some details of research done at Marshall University, USA, involving functional aspects of pancreatic beta cells in several experimental models: avian, transgenic mice, and beta-cell lines. In this book you will gain some knowledge of genetic engineering approaches to improve beta-cell insulin secretion which could be applied to manage models and cases of diabetes mellitus. This work is presented as three separate chapters. The first chapter aims to gain an understanding of the expression pattern of CaBP28k in the chicken pancreas and to explore its spatial relationships with insulin in beta cells. The second chapter is to identify the influence of CaBP28k-ablation on the dynamics of [Ca2+]i in response to glucose stimulation in murine beta cells of CaBP28k-KO mice pancreatic islets and wildtype islets. The third chapter is an attempt to elucidate the genomic and non-genomic effects of in vitro CaBP28k-ablation in a cultured beta-cell line. It highlights the effect...
Monosodium glutamate (MSG) is one of the most widely spread food additives that might cause male ... more Monosodium glutamate (MSG) is one of the most widely spread food additives that might cause male infertility. However, Nigellasativa L. seeds (NSS) could provide a solution. This study was designed to investigate the potential effects of NSS on rats ingesting MSG. To achieve this aim, adult male albino rats were randomly equally assigned into three groups for 21 days: control group received no treatment, MSG group received MSG as 30 g/kg feed, and MSG + NSS group received MSG as 30 g/kg and NSS as 30 g/kg feed. Testis histomorphometry showed marked deterioration by MSG as atrophic seminiferous tubules with degeneration of their lining cells, damaged Leydig cells and decreased germ cells number. Periodic Acid Schiff stain indicated irregular interrupted basement membranes. Glutathione reductase, superoxide dismutase 2 (SOD2), and caspase-3 immuno-expressions increased in testicular cells. Testosterone levels were significantly decreased in MSG challenged rats along with significant i...
Background: Swimming is a minor traumatic exercise for animals and has been commonly used to eluc... more Background: Swimming is a minor traumatic exercise for animals and has been commonly used to elucidate the physiologic and molecular responses of the muscle to exercise stress. Short term exhausting exercise increases the formation of harmful reactive oxygen species (ROS). Vitamin E ( α tocopherol) is a fat soluble vitamin that can inhibit the generation of ROS in the body as it acts as an antioxidant. Aim of the Study: The present study was designed to investigate the possible protective effect of vitamin E against the untrained exhaustive exercise-induced damage in the skeletal muscle, and on the plasma levels of proinflammatory cytokines in adult male albino rat. Material and Methods: 24 adult male albino rats, age 3 months and about 90-120g body weight were purchased from Animal House, Faculty of Medicine, Assiut University. All animals were kept in stainless-steel cages at room temperature at a natural photoperiod with free access to standard rat chow and tap water. Animals wer...
Background: Diabetes mellitus is a major risk factor of cardiovascular disease. There is evidence... more Background: Diabetes mellitus is a major risk factor of cardiovascular disease. There is evidence that vitamin D decreases type 1 diabetes mellitus risk during early adulthood and improves insulin secretion and resistance in diabetic patients. Low vitamin D level was observed to increase the cardiovascular disease. Objectives: This study aimed to assess the protective effect of vitamin D on diabetic vascular damages in aorta. Materials and Methods: 40 adult male rats were randomly divided into: group I(control), group II (vitamin D), group III (diabetic) and group VI(diabetic plus Vitamin D)(n = 10 rats /each group). Injection of streptozotocin (60 mg/kg) as a single dose intraperitoneal to induce diabetes. Vitamin D was administered orally every other day in a dose of 12.5 mg/kg. After 12weeksof treatment period, aortic samples were collected for histological examination. Results: Morphological changes of aortic tissue in diabetic untreated group in the form of reduction of tunica ...
Aim of work: To compare morphology of anterior cerebellar lobe's lobules: lobule III for hind... more Aim of work: To compare morphology of anterior cerebellar lobe's lobules: lobule III for hindlimb and lobules IV-V for forelimb movements among different vertebrates with emphasis on cerebellar structural-functional relationship. Material and Methods: Different adult vertebrates were used; from mammals: rat, cat, rabbit, cow, from avian: pigeon, bat and duck, from reptiles: snake, and from primates: human. Cerebella of all animals were examined for gross morphology and microscopic structure. In lobules III-IV-V, thicknesses of cerebellar cortical layers, Purkinje cell surface area, and Purkinje cell count were measured. Obtained data were statistically analyzed. Results: Snake׳s cerebellum didn't show foliations. Pigeon, duck and bat had large vermis with rudimentary cerebellar hemispheres. Rat, cat, rabbit and cow showed large complex foliations of cerebellar hemispheres and vermis. The human had massive cerebellar hemispheres and small vermis. Pigeon, duck and bat had well developed lobules IV-V and so did the cat. In contrast, rat and rabbit had well developed lobule III in comparison to lobules IV-V. In cow and human, lobules III-IV-V were well developed. Order of cerebellar cortical layers in different animals was similar. Significant differences were between lobule III and lobules IV-V in Purkinje cell count and cortical layers thickness following animals' behavior. In animals using hindlimbs more than forelimbs, mean numbers of those data showed significant increase in lobule III compared to lobules IV-V and vice versa. Conclusion: Variations in cerebellar morphology-structure are related to behavioral differences among animals. Degree of structural complexity of cerebellar lobules III-IV-V is related to limbs´ function.
Aging is associated with reduced hippocampal neurogenesis, which may in turn contribute to cognit... more Aging is associated with reduced hippocampal neurogenesis, which may in turn contribute to cognitive impairment. We assessed the effect of Ginkgo biloba (Gb) on hippocampal neurogenesis in elderly male mice using immunohistochemistry. We used anti-caspase-3 as a marker of apoptosis, anti-GFAP as a marker of neural stem cells, anti-Ki-67 as a specific marker for cellular proliferation and anti-doublecortin (DCX) to detect newly born neurons in the hippocampal dentate gyrus (DG) of aged male mice. The 24-month-old male mice were divided into two groups: a control group treated with distilled water and a group fed with Gb at a dose of 100 mg/kg once daily for 28 days. A sharp decrease in apoptotic cells in Gb-treated compared to nontreated mice was observed by anti-csapase-3 immunostaining. A large number of GFAP+ve cells was found in the subgranular zone of the DG of Gb-treated mice, suggesting an increase in the pool of neural stem cells by Gb treatment. There was also an increase in Ki-67 immunoreactive cells, indicating increased cell proliferation in the DG in the Gb-treated compared to nontreated group. A significant increase in newborn DCX+ve neurons with well-developed tertiary dendrites was also found in the Gb-treated compared to nontreated group. Using Western blot analysis, the expression of DCX protein in the Gb group was also significantly increased compared to the control. The results support a beneficial role of Gb on hippocampal neurogenesis in the context of brain aging.
This in vitro study aimed to investigate the possible mechanism underlying the protective effect ... more This in vitro study aimed to investigate the possible mechanism underlying the protective effect of growth hormone (GH) on hippocampal function during periods of heightened glucocorticoid exposure. This study was conducted between January and June 2005 at the Joan C. Edwards School of Medicine, Marshall University, in Huntington, West Virginia, USA. The effects of the co-application of GH and corticosterone (CORT) were tested at different concentrations on the field excitatory postsynaptic potentials (fEPSPs) of the hippocampal slices of rats in two different age groups. Changes in the protein expression of N-methyl-D-aspartate receptor (NMDAR) subunits NR1, NR2B and NR2A were measured in hippocampal brain slices treated with either artificial cerebrospinal fluid (ACSF), low doses of CORT alone or both CORT and GH for three hours. The co-application of CORT and GH was found to have an additive effect on hippocampal synaptic transmission compared to either drug alone. Furthermore, th...
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2007
Decreases in load are important cues in the control of posture and walking. We recorded activitie... more Decreases in load are important cues in the control of posture and walking. We recorded activities of the tibial campaniform sensilla, receptors that monitor forces as strains in the exoskeleton, in the middle legs of freely moving cockroaches. Small magnets were attached to the thorax and body load was changed by applying currents to a coil below the substrate. Body position was monitored by video recording. The tibial sensilla are organized into proximal and distal subgroups that have different response properties and reflex effects: proximal sensilla excite extensor motoneurons while distal receptors inhibit extensor firing. Sudden load decreases elicited bursts from distal sensilla, while increased load excited proximal receptors. The onset of sensory discharges closely approximated the time of peak velocity of body movement in both load decreases and increases. Firing of distal sensilla rapidly adapted to sustained unloading, while proximal sensilla discharged tonically to load...
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2006
We studied the mechanisms underlying support of body load in posture and walking in serially homo... more We studied the mechanisms underlying support of body load in posture and walking in serially homologous legs of cockroaches. Activities of the trochanteral extensor muscle in the front or middle legs were recorded neurographically while animals were videotaped. Body load was increased via magnets attached to the thorax and varied through a coil below the substrate. In posture, tonic firing of the slow trochanteral extensor motoneuron (Ds) in each leg was strongly modulated by changing body load. Rapid load increases produced decreases in body height and sharp increments in extensor firing. The peak of extensor activity more closely approximated the maximum velocity of body displacement than the body position. In walking, extensor bursts in front and middle legs were initiated during swing and continued into the stance phase. Moderate tonic increases in body load elicited similar, specific, phase dependent changes in both legs: extensor firing was not altered in swing but was higher after foot placement in stance. These motor adjustments to load are not anticipatory but apparently depend upon sensory feedback. These data are consistent with previous findings in the hind legs and support the idea that body load is countered by common motor mechanisms in serially homologous legs.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2007
Decreases in load are important cues in the control of posture and walking. We recorded activitie... more Decreases in load are important cues in the control of posture and walking. We recorded activities of the tibial campaniform sensilla, receptors that monitor forces as strains in the exoskeleton, in the middle legs of freely moving cockroaches. Small magnets were attached to the thorax and body load was changed by applying currents to a coil below the substrate. Body position was monitored by video recording. The tibial sensilla are organized into proximal and distal subgroups that have different response properties and reflex effects: proximal sensilla excite extensor motoneurons while distal receptors inhibit extensor firing. Sudden load decreases elicited bursts from distal sensilla, while increased load excited proximal receptors. The onset of sensory discharges closely approximated the time of peak velocity of body movement in both load decreases and increases. Firing of distal sensilla rapidly adapted to sustained unloading, while proximal sensilla discharged tonically to load increases. Load decreases of small amplitude or at low rates produced only inhibition of proximal activity while decrements of larger size or rate elicited distal firing. These response properties may provide discrete signals that either modulate excitatory extensor drive during small load variations or inhibit support prior to compensatory stepping or initiation of swing.
This book reveals some details of research done at Marshall University, USA, involving functional... more This book reveals some details of research done at Marshall University, USA, involving functional aspects of pancreatic beta cells in several experimental models: avian, transgenic mice, and beta-cell lines. In this book you will gain some knowledge of genetic engineering approaches to improve beta-cell insulin secretion which could be applied to manage models and cases of diabetes mellitus. This work is presented as three separate chapters. The first chapter aims to gain an understanding of the expression pattern of CaBP28k in the chicken pancreas and to explore its spatial relationships with insulin in beta cells. The second chapter is to identify the influence of CaBP28k-ablation on the dynamics of [Ca2+]i in response to glucose stimulation in murine beta cells of CaBP28k-KO mice pancreatic islets and wildtype islets. The third chapter is an attempt to elucidate the genomic and non-genomic effects of in vitro CaBP28k-ablation in a cultured beta-cell line. It highlights the effect...
Monosodium glutamate (MSG) is one of the most widely spread food additives that might cause male ... more Monosodium glutamate (MSG) is one of the most widely spread food additives that might cause male infertility. However, Nigellasativa L. seeds (NSS) could provide a solution. This study was designed to investigate the potential effects of NSS on rats ingesting MSG. To achieve this aim, adult male albino rats were randomly equally assigned into three groups for 21 days: control group received no treatment, MSG group received MSG as 30 g/kg feed, and MSG + NSS group received MSG as 30 g/kg and NSS as 30 g/kg feed. Testis histomorphometry showed marked deterioration by MSG as atrophic seminiferous tubules with degeneration of their lining cells, damaged Leydig cells and decreased germ cells number. Periodic Acid Schiff stain indicated irregular interrupted basement membranes. Glutathione reductase, superoxide dismutase 2 (SOD2), and caspase-3 immuno-expressions increased in testicular cells. Testosterone levels were significantly decreased in MSG challenged rats along with significant i...
Background: Swimming is a minor traumatic exercise for animals and has been commonly used to eluc... more Background: Swimming is a minor traumatic exercise for animals and has been commonly used to elucidate the physiologic and molecular responses of the muscle to exercise stress. Short term exhausting exercise increases the formation of harmful reactive oxygen species (ROS). Vitamin E ( α tocopherol) is a fat soluble vitamin that can inhibit the generation of ROS in the body as it acts as an antioxidant. Aim of the Study: The present study was designed to investigate the possible protective effect of vitamin E against the untrained exhaustive exercise-induced damage in the skeletal muscle, and on the plasma levels of proinflammatory cytokines in adult male albino rat. Material and Methods: 24 adult male albino rats, age 3 months and about 90-120g body weight were purchased from Animal House, Faculty of Medicine, Assiut University. All animals were kept in stainless-steel cages at room temperature at a natural photoperiod with free access to standard rat chow and tap water. Animals wer...
Background: Diabetes mellitus is a major risk factor of cardiovascular disease. There is evidence... more Background: Diabetes mellitus is a major risk factor of cardiovascular disease. There is evidence that vitamin D decreases type 1 diabetes mellitus risk during early adulthood and improves insulin secretion and resistance in diabetic patients. Low vitamin D level was observed to increase the cardiovascular disease. Objectives: This study aimed to assess the protective effect of vitamin D on diabetic vascular damages in aorta. Materials and Methods: 40 adult male rats were randomly divided into: group I(control), group II (vitamin D), group III (diabetic) and group VI(diabetic plus Vitamin D)(n = 10 rats /each group). Injection of streptozotocin (60 mg/kg) as a single dose intraperitoneal to induce diabetes. Vitamin D was administered orally every other day in a dose of 12.5 mg/kg. After 12weeksof treatment period, aortic samples were collected for histological examination. Results: Morphological changes of aortic tissue in diabetic untreated group in the form of reduction of tunica ...
Aim of work: To compare morphology of anterior cerebellar lobe's lobules: lobule III for hind... more Aim of work: To compare morphology of anterior cerebellar lobe's lobules: lobule III for hindlimb and lobules IV-V for forelimb movements among different vertebrates with emphasis on cerebellar structural-functional relationship. Material and Methods: Different adult vertebrates were used; from mammals: rat, cat, rabbit, cow, from avian: pigeon, bat and duck, from reptiles: snake, and from primates: human. Cerebella of all animals were examined for gross morphology and microscopic structure. In lobules III-IV-V, thicknesses of cerebellar cortical layers, Purkinje cell surface area, and Purkinje cell count were measured. Obtained data were statistically analyzed. Results: Snake׳s cerebellum didn't show foliations. Pigeon, duck and bat had large vermis with rudimentary cerebellar hemispheres. Rat, cat, rabbit and cow showed large complex foliations of cerebellar hemispheres and vermis. The human had massive cerebellar hemispheres and small vermis. Pigeon, duck and bat had well developed lobules IV-V and so did the cat. In contrast, rat and rabbit had well developed lobule III in comparison to lobules IV-V. In cow and human, lobules III-IV-V were well developed. Order of cerebellar cortical layers in different animals was similar. Significant differences were between lobule III and lobules IV-V in Purkinje cell count and cortical layers thickness following animals' behavior. In animals using hindlimbs more than forelimbs, mean numbers of those data showed significant increase in lobule III compared to lobules IV-V and vice versa. Conclusion: Variations in cerebellar morphology-structure are related to behavioral differences among animals. Degree of structural complexity of cerebellar lobules III-IV-V is related to limbs´ function.
Aging is associated with reduced hippocampal neurogenesis, which may in turn contribute to cognit... more Aging is associated with reduced hippocampal neurogenesis, which may in turn contribute to cognitive impairment. We assessed the effect of Ginkgo biloba (Gb) on hippocampal neurogenesis in elderly male mice using immunohistochemistry. We used anti-caspase-3 as a marker of apoptosis, anti-GFAP as a marker of neural stem cells, anti-Ki-67 as a specific marker for cellular proliferation and anti-doublecortin (DCX) to detect newly born neurons in the hippocampal dentate gyrus (DG) of aged male mice. The 24-month-old male mice were divided into two groups: a control group treated with distilled water and a group fed with Gb at a dose of 100 mg/kg once daily for 28 days. A sharp decrease in apoptotic cells in Gb-treated compared to nontreated mice was observed by anti-csapase-3 immunostaining. A large number of GFAP+ve cells was found in the subgranular zone of the DG of Gb-treated mice, suggesting an increase in the pool of neural stem cells by Gb treatment. There was also an increase in Ki-67 immunoreactive cells, indicating increased cell proliferation in the DG in the Gb-treated compared to nontreated group. A significant increase in newborn DCX+ve neurons with well-developed tertiary dendrites was also found in the Gb-treated compared to nontreated group. Using Western blot analysis, the expression of DCX protein in the Gb group was also significantly increased compared to the control. The results support a beneficial role of Gb on hippocampal neurogenesis in the context of brain aging.
This in vitro study aimed to investigate the possible mechanism underlying the protective effect ... more This in vitro study aimed to investigate the possible mechanism underlying the protective effect of growth hormone (GH) on hippocampal function during periods of heightened glucocorticoid exposure. This study was conducted between January and June 2005 at the Joan C. Edwards School of Medicine, Marshall University, in Huntington, West Virginia, USA. The effects of the co-application of GH and corticosterone (CORT) were tested at different concentrations on the field excitatory postsynaptic potentials (fEPSPs) of the hippocampal slices of rats in two different age groups. Changes in the protein expression of N-methyl-D-aspartate receptor (NMDAR) subunits NR1, NR2B and NR2A were measured in hippocampal brain slices treated with either artificial cerebrospinal fluid (ACSF), low doses of CORT alone or both CORT and GH for three hours. The co-application of CORT and GH was found to have an additive effect on hippocampal synaptic transmission compared to either drug alone. Furthermore, th...
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2007
Decreases in load are important cues in the control of posture and walking. We recorded activitie... more Decreases in load are important cues in the control of posture and walking. We recorded activities of the tibial campaniform sensilla, receptors that monitor forces as strains in the exoskeleton, in the middle legs of freely moving cockroaches. Small magnets were attached to the thorax and body load was changed by applying currents to a coil below the substrate. Body position was monitored by video recording. The tibial sensilla are organized into proximal and distal subgroups that have different response properties and reflex effects: proximal sensilla excite extensor motoneurons while distal receptors inhibit extensor firing. Sudden load decreases elicited bursts from distal sensilla, while increased load excited proximal receptors. The onset of sensory discharges closely approximated the time of peak velocity of body movement in both load decreases and increases. Firing of distal sensilla rapidly adapted to sustained unloading, while proximal sensilla discharged tonically to load...
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2006
We studied the mechanisms underlying support of body load in posture and walking in serially homo... more We studied the mechanisms underlying support of body load in posture and walking in serially homologous legs of cockroaches. Activities of the trochanteral extensor muscle in the front or middle legs were recorded neurographically while animals were videotaped. Body load was increased via magnets attached to the thorax and varied through a coil below the substrate. In posture, tonic firing of the slow trochanteral extensor motoneuron (Ds) in each leg was strongly modulated by changing body load. Rapid load increases produced decreases in body height and sharp increments in extensor firing. The peak of extensor activity more closely approximated the maximum velocity of body displacement than the body position. In walking, extensor bursts in front and middle legs were initiated during swing and continued into the stance phase. Moderate tonic increases in body load elicited similar, specific, phase dependent changes in both legs: extensor firing was not altered in swing but was higher after foot placement in stance. These motor adjustments to load are not anticipatory but apparently depend upon sensory feedback. These data are consistent with previous findings in the hind legs and support the idea that body load is countered by common motor mechanisms in serially homologous legs.
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2007
Decreases in load are important cues in the control of posture and walking. We recorded activitie... more Decreases in load are important cues in the control of posture and walking. We recorded activities of the tibial campaniform sensilla, receptors that monitor forces as strains in the exoskeleton, in the middle legs of freely moving cockroaches. Small magnets were attached to the thorax and body load was changed by applying currents to a coil below the substrate. Body position was monitored by video recording. The tibial sensilla are organized into proximal and distal subgroups that have different response properties and reflex effects: proximal sensilla excite extensor motoneurons while distal receptors inhibit extensor firing. Sudden load decreases elicited bursts from distal sensilla, while increased load excited proximal receptors. The onset of sensory discharges closely approximated the time of peak velocity of body movement in both load decreases and increases. Firing of distal sensilla rapidly adapted to sustained unloading, while proximal sensilla discharged tonically to load increases. Load decreases of small amplitude or at low rates produced only inhibition of proximal activity while decrements of larger size or rate elicited distal firing. These response properties may provide discrete signals that either modulate excitatory extensor drive during small load variations or inhibit support prior to compensatory stepping or initiation of swing.
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