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Chandra Mohini Chaturvedi - One of the best experts on this subject based on the ideXlab platform.
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impact of estrogen and photoperiod on arginine vasotocin and vt3 receptor expression in the Shell Gland of quail
Frontiers in Bioscience, 2018Co-Authors: Rashmi Srivastava, Lawrence E Cornett, Chandra Mohini ChaturvediAbstract:Role of estrogen and photoperiod is well-established in avian reproduction. In addition, the distribution and the expression of arginine vasotocin (AVT) and its receptor VT3 to ensure reproductive/breeding conditions in Japanese quail influenced by them has been the main focus of this review. To consider this aspect the mRNA expression of VT3 receptor and its ligand AVT in the Shell Gland has been emphasized. In birds, AVT performs a dual role as an anti-diuretic hormone and the functions accomplished by oxytocin in mammals. The physiological actions of AVT in birds are mediated through its diverse receptor subtypes VT1, VT2, VT3 and VT4. Dynamic alteration of VT3 expression during different reproductive and photo-sexual conditions of quail can be modulated by estrogen. In addition to the endocrine effect of AVT, the Shell Gland is complemented by its paracrine action via its receptors. Evidences indicate that the expression of Shell Gland AVT modulated by estrogen appears to play a priming role by modulating the availability of VT3 receptor for the required action of neurohypophysial AVT during oviposition.
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expression of arginine vasotocin and estrogen receptor alpha erα in the Shell Gland altered by the specific phase relations of neural oscillations affects the reproductive physiology of japanese quail
Physiology & Behavior, 2016Co-Authors: Rashmi Srivastava, Chandra Mohini ChaturvediAbstract:In order to study the effect of specific phase relation of neural oscillations on reproductive regulation and the response of AVT (the avian homologue of mammalian AVP) the expression of AVT in the Shell Gland was monitored in sexually immature quail. In this study 3-week-old female Japanese quail were administered with serotonin precursor, 5-hydroxytryptophan followed by the dopamine precursor, l-dihydroxyphenylalanine at interval of 8h and 12h daily over a period of 13days. At thirty two days post treatment, a significant decrease in gonadal activity was seen in 8h quail although 12h quail exhibited an increase as compared to controls. A significant decrease in plasma estradiol level was noted in 8h quail while 12h exhibited no significant difference compared to controls. To address the relative roles of estrogen mediated action we also investigated estrogen receptor alpha (ER-α) expression and localization in the Shell Gland by visualizing it through confocal immuno-fluorescence microscopy. Results indicate increased expression of immunoreactive (ir)-AVT (myometrium), ir-ER-α (epithelial cells of endometrial region), along with significant increase in hypothalamic, plasma and Shell Gland AVT and a rapid increase in egg laying thus maintaining full breeding condition in 12h while low expression of ir-AVT and ir-ER-α was observed in 8h quail along with a significant decrease in hypothalamic, plasma and Shell Gland AVT with the suppression of gonads thereby stopping the egg-laying behaviour was noted. These findings not only suggest the modulation of gonadal development by changing the specific phase relation of neural oscillations but also demonstrate a parallel relation of AVT and gonadal activity in both conditions. It is concluded that the egg laying performance in response to AVT is regulated by the temporal phase relationship of neurotransmitters, and in part, this effect appears to be estrogen dependent.
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age photoperiod and estrogen dependent variations in the Shell Gland and the expression of avt in the ovary of japanese quail
Steroids, 2012Co-Authors: Rashmi Srivastava, Chandra Mohini ChaturvediAbstract:Present work was undertaken to describe (i) age dependent (prepuberal-3, 4, 5 and 6 weeks old, puberal and actively laying 8 and 12 weeks old and aged 78 weeks old) (ii) photoperiodic response dependent (photosensitive and photorefractory) and sex steroid dependent (estradiol benzoate and its antagonist tamoxifen treated) variation in the ovary and Shell Gland activity of Japanese quail (Coturnix coturnix japonica). Further, in view of the role of neurohypophysial peptide arginine vasotocin (AVT) in many physiological processes including age/reproduction related oviposition, expression of ir-AVT was also monitored in the ovary of quail. All the parameters associated with histodifferentiation increased rapidly during the developing stages followed by a decrease in old age, which also increased in reproductively quiescent photorefractory birds following estradiol treatment and decreased in reproductively active photosensitive quail following tamoxifen treatment. Using AVT-specific antibody, expression of immunoreactive AVT (ir-AVT) observed in the ovary of photosensitive quail was not detected in the photorefractory quail. However, administration of estrogen in the photorefractory quail stimulated the growth and activity of ovary and Shell Gland also resulted in the expression of ovarian ir-AVT. On the other hand, tamoxifen eliminated the localization of ir-AVT in the ovary of photosensitive quail in addition to a decrease in the Shell Gland protein and alkaline phosphatase activity. It is concluded that estrogen not only affects the growth and differentiation of ovary and oviduct including Shell Gland but also regulates the expression of ovarian AVT. It is also suggested that in addition to reported paracrine effect of AVT in the Shell Gland of Japanese quail for oviposition, ovarian AVT may also affect ovarian function (ovulation), and in part, this regulation is estrogen dependent.
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effect of estrogen and tamoxifen on the Shell Gland avt and vt3r of scotosensitive and scotorefractory japanese quail
General and Comparative Endocrinology, 2010Co-Authors: Rashmi Srivastava, Chandra Mohini ChaturvediAbstract:The neurohypophyseal hormone arginine vasotocin (AVT) found in most vertebrate species is known to modulate different aspects of reproduction in quail. AVT system is sensitive to gonadal steroids. Previous studies have shown that estradiol benzoate stimulates the proliferation of Shell Gland and increases the AVT and the vasotocin 3 receptor (VT3R) in long day length. This study was undertaken to investigate the effect of estrogen and tamoxifen on AVT as well as its receptor VT3 under the short day condition (6L:18D). Estradiol benzoate (EB) was administered daily in sexually quiescent (scotosensitive) condition for 15days. After the initial period of sexual quiescence, the quail of control group exhibited sexual development (scotorefractory condition). Thereafter, scotorefractory quail were administered with anti-estrogen tamoxifen, which eliminated the reoccurrence of scotosensitivity. Immunohistochemical and in-situ hybridization studies indicate the expression of AVT and VT3R transcripts in both scotosensitive as well as scotorefractory conditions. Administration of EB to scotosensitive female quail produced an increase in AVT and VT3 while tamoxifen suppressed them in scotorefractory quail. The results indicate that in quail myometrium the expression of VT3R is upregulated by estrogen when kept under short day condition.
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age dependent expression of avt and its oxytocic like receptor vt3 in the Shell Gland of japanese quail coturnix coturnix japonica
General and Comparative Endocrinology, 2010Co-Authors: Rashmi Srivastava, Lawrence E Cornett, Chandra Mohini ChaturvediAbstract:The avian neurohypophyseal hormone AVT is an important regulatory hormone involved in many physiological processes including oviposition; an age-related phenomenon, through its action on the Shell Gland. In this study, immunohistochemistry and in situ hybridization was performed to study the expression of immunoreactive (ir) AVT and its oxytocic-like receptor VT3 transcript in the ovary/Shell Gland of Japanese quail representing sexually immature, mature and old condition. Our results indicate that ir-AVT is present in the ovary of sexually active adult only, but in the Shell Gland it is observed in both sexually active adult and sexually quiescent old quail. Further, VT3 gene transcript although not detected in the Shell Gland of sexually immature birds, has been found abundantly in the myometrium of Shell Gland of sexually active adult quail with a slight decrease in old birds. It is concluded that in addition to the ovarian function and Shell Gland activity, the expression of AVT and VT3 receptor in the Shell Gland also varies with the age dependent reproductive/egg laying performance of the Japanese quail. Our findings also suggest that (i) local synthesis of AVT and the expression of its oxytocic-like VT3 receptors is estrogen dependent and (ii) Shell Gland AVT upregulates its VT3 receptor (paracrine role) in advance to facilitate the role of neurohypophyseal AVT during oviposition.
Rashmi Srivastava - One of the best experts on this subject based on the ideXlab platform.
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expression of estrogen receptor alpha in response to stress and estrogen antagonist tamoxifen in the Shell Gland of gallus gallus domesticus involvement of anti oxidant system and estrogen
Stress, 2021Co-Authors: Mukesh Kumar Niranjan, Raj Kumar Koiri, Rashmi SrivastavaAbstract:Animals are frequently exposed to various kinds of environmental stressors and estrogen is known to play important role in stress response besides its crucial role in regulation of cellular proliferation, metabolic activity and reproduction. The study investigates the estrogen antagonist, tamoxifen (TM), mediated estrogen receptor alpha (ERα) expression, to modulate stress induced parameters in chickens. The study further explores the activity of superoxide dismutase (SOD), catalase and glutathione peroxidase (GPX) and malonaldehyde (MDA) in brain, ovary and Shell Gland during water deprivation (WD) and tamoxifen administration in sexually mature chicken. WD and TM administration both decrease the plasma estradiol while WD increases corticosterone. WD also elevates MDA concentration in the brain, ovary and Shell Gland while TM lowers it. WD and TM administration lowers the specific activity of SOD in brain and Shell Gland. In contrast, WD increases the specific activity of catalase, GPx and GR in the brain and Shell Gland, while TM decreases it. It appears that endogenous estradiol plays a crucial role in expression of antioxidant enzymes and tamoxifen acts as an antioxidant by reducing the oxidative stress in chicken. Abundant expression of ERα has been observed in the Shell Gland of egg laying birds while stress like water deprivation and TM down-regulates its expression. Thus, it can be concluded that expression of ERα in Shell Gland plays a predominant role in mediating estrogen action in response to water deprivation stress and tamoxifen.
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expression of estrogen receptor alpha in developing brain ovary and Shell Gland of gallus gallus domesticus impact of stress and estrogen
Steroids, 2019Co-Authors: Mukesh Kumar Niranjan, Rashmi SrivastavaAbstract:Abstract Estrogen plays a central role in the control of reproductive behaviour and in the regulation of neuroendocrine system. To elucidate the mechanism by which it controls the stress-modulated functions, it is important to understand how estrogenic effects are mediated. The distribution of estrogen receptor alpha (ERα) protein in brain, ovary and Shell Gland of chickens has been investigated. Immature chickens were taken and randomly divided into four groups. First group served as control (C), second water deprived for two days (WD), third treated with estradiol benzoate (E) and fourth treated with estradiol benzoate followed by water deprivation during last two days of treatment (E + WD). The dose of estradiol benzoate administered for 15 days was 0.5 mg/100 g. Immuno-fluorescent localization demonstrated the presence of ER alpha (ERα) in hypothalamic area, principally the pre-optic area on estrogen administration. However, ERα expression in brain decreased on water deprivation. ERα expression was observed highly in granulosa and thecal cells of E and E + WD ovary compared to immature while least on water deprivation. Similarly, ERα expression was abundant in tunica muscularis and epithelial cells of E and E + WD Shell Gland while lesser in WD. Plasma estradiol significantly increased in E and E + WD group while decreased on water deprivation. Plasma corticosterone decreased significantly in E and E + WD group while increased in WD. Therefore, we conclude that administration of estradiol in stress decreases corticosterone induced sensitivity mediated by an increased expression of ERα in brain, ovary and Shell Gland. It appears that negative feedback regulation is involved between HPA-axis and HPG- axis during stress in chickens.
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impact of estrogen and photoperiod on arginine vasotocin and vt3 receptor expression in the Shell Gland of quail
Frontiers in Bioscience, 2018Co-Authors: Rashmi Srivastava, Lawrence E Cornett, Chandra Mohini ChaturvediAbstract:Role of estrogen and photoperiod is well-established in avian reproduction. In addition, the distribution and the expression of arginine vasotocin (AVT) and its receptor VT3 to ensure reproductive/breeding conditions in Japanese quail influenced by them has been the main focus of this review. To consider this aspect the mRNA expression of VT3 receptor and its ligand AVT in the Shell Gland has been emphasized. In birds, AVT performs a dual role as an anti-diuretic hormone and the functions accomplished by oxytocin in mammals. The physiological actions of AVT in birds are mediated through its diverse receptor subtypes VT1, VT2, VT3 and VT4. Dynamic alteration of VT3 expression during different reproductive and photo-sexual conditions of quail can be modulated by estrogen. In addition to the endocrine effect of AVT, the Shell Gland is complemented by its paracrine action via its receptors. Evidences indicate that the expression of Shell Gland AVT modulated by estrogen appears to play a priming role by modulating the availability of VT3 receptor for the required action of neurohypophysial AVT during oviposition.
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expression of arginine vasotocin and estrogen receptor alpha erα in the Shell Gland altered by the specific phase relations of neural oscillations affects the reproductive physiology of japanese quail
Physiology & Behavior, 2016Co-Authors: Rashmi Srivastava, Chandra Mohini ChaturvediAbstract:In order to study the effect of specific phase relation of neural oscillations on reproductive regulation and the response of AVT (the avian homologue of mammalian AVP) the expression of AVT in the Shell Gland was monitored in sexually immature quail. In this study 3-week-old female Japanese quail were administered with serotonin precursor, 5-hydroxytryptophan followed by the dopamine precursor, l-dihydroxyphenylalanine at interval of 8h and 12h daily over a period of 13days. At thirty two days post treatment, a significant decrease in gonadal activity was seen in 8h quail although 12h quail exhibited an increase as compared to controls. A significant decrease in plasma estradiol level was noted in 8h quail while 12h exhibited no significant difference compared to controls. To address the relative roles of estrogen mediated action we also investigated estrogen receptor alpha (ER-α) expression and localization in the Shell Gland by visualizing it through confocal immuno-fluorescence microscopy. Results indicate increased expression of immunoreactive (ir)-AVT (myometrium), ir-ER-α (epithelial cells of endometrial region), along with significant increase in hypothalamic, plasma and Shell Gland AVT and a rapid increase in egg laying thus maintaining full breeding condition in 12h while low expression of ir-AVT and ir-ER-α was observed in 8h quail along with a significant decrease in hypothalamic, plasma and Shell Gland AVT with the suppression of gonads thereby stopping the egg-laying behaviour was noted. These findings not only suggest the modulation of gonadal development by changing the specific phase relation of neural oscillations but also demonstrate a parallel relation of AVT and gonadal activity in both conditions. It is concluded that the egg laying performance in response to AVT is regulated by the temporal phase relationship of neurotransmitters, and in part, this effect appears to be estrogen dependent.
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age photoperiod and estrogen dependent variations in the Shell Gland and the expression of avt in the ovary of japanese quail
Steroids, 2012Co-Authors: Rashmi Srivastava, Chandra Mohini ChaturvediAbstract:Present work was undertaken to describe (i) age dependent (prepuberal-3, 4, 5 and 6 weeks old, puberal and actively laying 8 and 12 weeks old and aged 78 weeks old) (ii) photoperiodic response dependent (photosensitive and photorefractory) and sex steroid dependent (estradiol benzoate and its antagonist tamoxifen treated) variation in the ovary and Shell Gland activity of Japanese quail (Coturnix coturnix japonica). Further, in view of the role of neurohypophysial peptide arginine vasotocin (AVT) in many physiological processes including age/reproduction related oviposition, expression of ir-AVT was also monitored in the ovary of quail. All the parameters associated with histodifferentiation increased rapidly during the developing stages followed by a decrease in old age, which also increased in reproductively quiescent photorefractory birds following estradiol treatment and decreased in reproductively active photosensitive quail following tamoxifen treatment. Using AVT-specific antibody, expression of immunoreactive AVT (ir-AVT) observed in the ovary of photosensitive quail was not detected in the photorefractory quail. However, administration of estrogen in the photorefractory quail stimulated the growth and activity of ovary and Shell Gland also resulted in the expression of ovarian ir-AVT. On the other hand, tamoxifen eliminated the localization of ir-AVT in the ovary of photosensitive quail in addition to a decrease in the Shell Gland protein and alkaline phosphatase activity. It is concluded that estrogen not only affects the growth and differentiation of ovary and oviduct including Shell Gland but also regulates the expression of ovarian AVT. It is also suggested that in addition to reported paracrine effect of AVT in the Shell Gland of Japanese quail for oviposition, ovarian AVT may also affect ovarian function (ovulation), and in part, this regulation is estrogen dependent.
Samiullah Khan - One of the best experts on this subject based on the ideXlab platform.
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genes involved in mitochondrial biogenesis and function may not show synchronised responses to mitochondria in Shell Gland of laying chickens under infectious bronchitis virus challenge
BMC Molecular and Cell Biology, 2019Co-Authors: Samiullah Khan, J R RobertsAbstract:Egg formation takes place in the oviduct of laying hens over a 24 h period. Infectious bronchitis virus (IBV) causes pathological lesions in the chicken oviduct. In the current study, mitochondrial counts were determined in three different segments of the oviduct during egg formation in laying chickens challenged with IBV T strain. Nuclear DNA encoded genes that are involved in mitochondrial biogenesis, fission and function were studied in the Shell Gland of the oviduct undergoing virus multiplication. In the Shell Gland, the mitochondrial count was significantly lower (P 0.05). Differential expression of the genes was observed at different time-points of egg-Shell formation. The expression levels of citrate synthase (CS), cytochrome C, somatic (CYC, S) and sodium-potassium adenosine triphosphatase (Na+-K+ATPase) genes were significantly higher, while those of SDHA and dynamin related protein 1 (Drp1) genes were significantly lower, at 15 h compared with 5 h following oviposition of the previous egg. The expression level of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) did not show significant change at different time-points. It was concluded that IBV T strain infection in laying hens reduced mitochondrial counts only in the Shell Gland region of the oviduct. The genes involved in mitochondrial biogenesis or function may not show synchronised responses to that of mitochondria in the Shell Gland of chickens under T strain of IBV challenge.
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rna sequencing analysis of Shell Gland shows differences in gene expression profile at two time points of eggShell formation in laying chickens
BMC Genomics, 2019Co-Authors: Samiullah Khan, J R RobertsAbstract:EggShell formation takes place in the Shell Gland of the oviduct of laying hens. The eggShell is rich in calcium and various glycoproteins synthesised in the Shell Gland. Although studies have identified genes involved in eggShell formation, little is known about the regulation of genes in the Shell Gland particularly in a temporal manner. The current study investigated the global gene expression profile of the Shell Gland of laying hens at different time-points of eggShell formation using RNA-Sequencing (RNA-Seq) analysis. Gene expression profiles of the Shell Gland tissue at 5 and 15 h time-points were clearly distinct from each other. Out of the 14,334 genes assessed for differential expression in the Shell Gland tissue, 278 genes were significantly down-regulated (log2 fold change > 1.5; FDR < 0.05) and 413 genes were significantly up-regulated at 15 h relative to the 5 h time-point of eggShell formation. The down-regulated genes annotated to Gene Ontology (GO) terms showed anion transport, synaptic vesicle localisation, organic anion transport, secretion and signal release as the five most enriched terms. The up-regulated gene annotation showed regulation of phospholipase activities, alanine transport, transmembrane receptor protein tyrosine kinase signalling pathway, regulation of blood vessels diameter and 3, 5-cyclic nucleotide phosphodiesterase activity as the five most enriched GO terms. The putative functions of genes identified ranged from calcium binding to receptor activity. Validation of RNA-Seq results through qPCR showed a positive correlation. The down-regulated genes at 15 h relative to the 5 h time-point were most likely involved in the transport of molecules and synthesis activities, initiating the formation of the eggShell. The up-regulated genes were most likely involved in calcium transportation, as well as synthesis and secretory activities of ions and molecules, reflecting the peak stage of eggShell formation. The findings in the current study improve our understanding of eggShell formation at the molecular level and provide a foundation for further studies of mRNA and possibly microRNA regulation involved in eggShell formation in the Shell Gland of laying hens.
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RNA-sequencing analysis of Shell Gland shows differences in gene expression profile at two time-points of eggShell formation in laying chickens
BMC Genomics, 2019Co-Authors: Samiullah Khan, Juliet RobertsAbstract:Background EggShell formation takes place in the Shell Gland of the oviduct of laying hens. The eggShell is rich in calcium and various glycoproteins synthesised in the Shell Gland. Although studies have identified genes involved in eggShell formation, little is known about the regulation of genes in the Shell Gland particularly in a temporal manner. The current study investigated the global gene expression profile of the Shell Gland of laying hens at different time-points of eggShell formation using RNA-Sequencing (RNA-Seq) analysis. Results Gene expression profiles of the Shell Gland tissue at 5 and 15 h time-points were clearly distinct from each other. Out of the 14,334 genes assessed for differential expression in the Shell Gland tissue, 278 genes were significantly down-regulated (log_2 fold change > 1.5; FDR
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Reference gene selection for gene expression study in Shell Gland and spleen of laying hens challenged with infectious bronchitis virus
Scientific Reports, 2017Co-Authors: Samiullah Khan, Juliet Roberts, Shu-biao WuAbstract:Ten reference genes were investigated for normalisation of candidate target gene expression data in the Shell Gland and spleen of laying hens challenged with two strains of infectious bronchitis virus (IBV). Data were analysed with geNorm, NormFinder and BestKeeper, and a comprehensive ranking (geomean) was calculated. In the combined data set of IBV challenged Shell Gland samples, the comprehensive ranking showed TATA-box binding protein ( TBP ) and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta ( YWHAZ ) as the two most stable, and succinate dehydrogenase complex flavoprotein subunit A ( SDHA ) and albumin ( ALB ) as the two least stable reference genes. In the spleen, and in the combined data set of the Shell Gland and spleen, the two most stable and the two least stable reference genes were TBP and YWHAZ , and ribosomal protein L4 ( RPL4 ) and ALB , respectively. Different ranking has been due to different algorithms. Validation studies showed that the use of the two most stable reference genes produced accurate and more robust gene expression data. The two most and least stable reference genes obtained in the study, were further used for candidate target gene expression data normalisation of the Shell Gland and spleen under an IBV infection model.
J R Roberts - One of the best experts on this subject based on the ideXlab platform.
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genes involved in mitochondrial biogenesis and function may not show synchronised responses to mitochondria in Shell Gland of laying chickens under infectious bronchitis virus challenge
BMC Molecular and Cell Biology, 2019Co-Authors: Samiullah Khan, J R RobertsAbstract:Egg formation takes place in the oviduct of laying hens over a 24 h period. Infectious bronchitis virus (IBV) causes pathological lesions in the chicken oviduct. In the current study, mitochondrial counts were determined in three different segments of the oviduct during egg formation in laying chickens challenged with IBV T strain. Nuclear DNA encoded genes that are involved in mitochondrial biogenesis, fission and function were studied in the Shell Gland of the oviduct undergoing virus multiplication. In the Shell Gland, the mitochondrial count was significantly lower (P 0.05). Differential expression of the genes was observed at different time-points of egg-Shell formation. The expression levels of citrate synthase (CS), cytochrome C, somatic (CYC, S) and sodium-potassium adenosine triphosphatase (Na+-K+ATPase) genes were significantly higher, while those of SDHA and dynamin related protein 1 (Drp1) genes were significantly lower, at 15 h compared with 5 h following oviposition of the previous egg. The expression level of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) did not show significant change at different time-points. It was concluded that IBV T strain infection in laying hens reduced mitochondrial counts only in the Shell Gland region of the oviduct. The genes involved in mitochondrial biogenesis or function may not show synchronised responses to that of mitochondria in the Shell Gland of chickens under T strain of IBV challenge.
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rna sequencing analysis of Shell Gland shows differences in gene expression profile at two time points of eggShell formation in laying chickens
BMC Genomics, 2019Co-Authors: Samiullah Khan, J R RobertsAbstract:EggShell formation takes place in the Shell Gland of the oviduct of laying hens. The eggShell is rich in calcium and various glycoproteins synthesised in the Shell Gland. Although studies have identified genes involved in eggShell formation, little is known about the regulation of genes in the Shell Gland particularly in a temporal manner. The current study investigated the global gene expression profile of the Shell Gland of laying hens at different time-points of eggShell formation using RNA-Sequencing (RNA-Seq) analysis. Gene expression profiles of the Shell Gland tissue at 5 and 15 h time-points were clearly distinct from each other. Out of the 14,334 genes assessed for differential expression in the Shell Gland tissue, 278 genes were significantly down-regulated (log2 fold change > 1.5; FDR < 0.05) and 413 genes were significantly up-regulated at 15 h relative to the 5 h time-point of eggShell formation. The down-regulated genes annotated to Gene Ontology (GO) terms showed anion transport, synaptic vesicle localisation, organic anion transport, secretion and signal release as the five most enriched terms. The up-regulated gene annotation showed regulation of phospholipase activities, alanine transport, transmembrane receptor protein tyrosine kinase signalling pathway, regulation of blood vessels diameter and 3, 5-cyclic nucleotide phosphodiesterase activity as the five most enriched GO terms. The putative functions of genes identified ranged from calcium binding to receptor activity. Validation of RNA-Seq results through qPCR showed a positive correlation. The down-regulated genes at 15 h relative to the 5 h time-point were most likely involved in the transport of molecules and synthesis activities, initiating the formation of the eggShell. The up-regulated genes were most likely involved in calcium transportation, as well as synthesis and secretory activities of ions and molecules, reflecting the peak stage of eggShell formation. The findings in the current study improve our understanding of eggShell formation at the molecular level and provide a foundation for further studies of mRNA and possibly microRNA regulation involved in eggShell formation in the Shell Gland of laying hens.
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reference gene selection for the Shell Gland of laying hens in response to time points of eggShell formation and nicarbazin
PLOS ONE, 2017Co-Authors: Sami Samiullah, J R RobertsAbstract:Ten reference genes were investigated for normalization of gene expression data in the Shell Gland of laying hens. Analyses performed with geNorm revealed that hypoxanthine phosphoribosyltransferase 1 (HPRT1) and hydroxymethylbilane synthase (HMBS) were the two most stable reference genes in response to post-oviposition time alone (POT) or with nicarbazin treatment (POT+N) of laying hens. NormFinder analyses showed that the two most stable reference genes in response to POT and POT+N were 18S ribosomal RNA (18S rRNA), ribosomal protein L4 (RPL4) and HMBS, RPL4, respectively. BestKeeper analyses showed that 18S rRNA, RPL4 and HPRT1, HMBS were the two most stable reference genes for POT, and POT+N, respectively. Of the ten reference genes, all except B2M showed geNorm M <0.5, suggesting that they were stably expressed in the Shell Gland tissue. Consensus from these three programs suggested HPRT1 and HMBS could be used as the two most stable reference genes in the present study. Expression analyses of four candidate target genes with the two most and the two least stable genes showed that a combination of stable reference genes leads to more discriminable quantification of expression levels of target genes, while the least stable genes failed to do so. Therefore, HMBS and HPRT1 are recommended as the two most stable reference genes for the normalization of gene expression data at different stages of eggShell formation in brown-egg laying hens. Available statistical programs for reference gene ranking should include more robust analysis capability to analyse the gene expression data generated from factorial design experiments.
Yvonne Ridderstråle - One of the best experts on this subject based on the ideXlab platform.
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Age-related changes in the Shell Gland and duodenum in relation to Shell quality and bone strength in commercial laying hen hybrids
Acta Veterinaria Scandinavica, 2019Co-Authors: Anna Wistedt, Yvonne Ridderstråle, Helena Wall, Lena HolmAbstract:Background During the production period of laying hens, the number of cracked eggShells increases and the skeleton becomes brittle. Both these problems are related to ageing of the hen and cause economic problems for egg producers and impaired animal welfare. This study investigated key factors in the Shell Gland and duodenum related to eggShell quality and bone strength in laying hens during the production period. Five Lohmann Selected Leghorn (LSL) and five Lohmann Brown (LB), common hybrids in commercial egg production, were euthanized at 21, 29, 49 and 70 weeks (wk) of age. Blood samples for analysis of total calcium were taken at euthanization. Right femur and humerus were used for bone strength measurements and tissue samples from Shell Gland and duodenum were processed for morphology, immunohistochemical localisation of oestrogen receptors (ERα, ERβ), plasma membrane calcium ATPase (PMCA) and histochemical localisation of carbonic anhydrases (CA). Eggs were collected for Shell quality measurements. Results At age 49 week, Shell and bone strength had both deteriorated, but the hens were then able to maintain the level until 70 week of age and femur bone strength even improved. The main physiological findings associated with the effects seen at 49 week were reduced Gland density and a shift in balance between ERα and ERβ in the Shell Gland, which coincided with a reduction in CA activity in the duodenum. Somewhat surprisingly, capillary density and capillaries with CA activity both increased in the Shell Gland over time, the latter possibly mediated via ERβ. These findings were independent of hybrid. PMCA was found in both Shell Gland and duodenum, but appeared unrelated to the age-related changes in Shell and bone quality. Conclusions In hens around half-way through the production period, both Shell quality and bone strength had deteriorated. Decreased Gland density and a shift in the balance between ERα and ERβ in the Shell Gland, co-occurring with a dramatic drop in duodenal CA activity, are suggested as possible factors involved in age-related changes in Shell and bone quality.
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age related changes in the Shell Gland and duodenum in relation to Shell quality and bone strength in commercial laying hen hybrids
Acta Veterinaria Scandinavica, 2019Co-Authors: Anna Wistedt, Yvonne Ridderstråle, Helena Wall, Lena HolmAbstract:During the production period of laying hens, the number of cracked eggShells increases and the skeleton becomes brittle. Both these problems are related to ageing of the hen and cause economic problems for egg producers and impaired animal welfare. This study investigated key factors in the Shell Gland and duodenum related to eggShell quality and bone strength in laying hens during the production period. Five Lohmann Selected Leghorn (LSL) and five Lohmann Brown (LB), common hybrids in commercial egg production, were euthanized at 21, 29, 49 and 70 weeks (wk) of age. Blood samples for analysis of total calcium were taken at euthanization. Right femur and humerus were used for bone strength measurements and tissue samples from Shell Gland and duodenum were processed for morphology, immunohistochemical localisation of oestrogen receptors (ERα, ERβ), plasma membrane calcium ATPase (PMCA) and histochemical localisation of carbonic anhydrases (CA). Eggs were collected for Shell quality measurements. At age 49 week, Shell and bone strength had both deteriorated, but the hens were then able to maintain the level until 70 week of age and femur bone strength even improved. The main physiological findings associated with the effects seen at 49 week were reduced Gland density and a shift in balance between ERα and ERβ in the Shell Gland, which coincided with a reduction in CA activity in the duodenum. Somewhat surprisingly, capillary density and capillaries with CA activity both increased in the Shell Gland over time, the latter possibly mediated via ERβ. These findings were independent of hybrid. PMCA was found in both Shell Gland and duodenum, but appeared unrelated to the age-related changes in Shell and bone quality. In hens around half-way through the production period, both Shell quality and bone strength had deteriorated. Decreased Gland density and a shift in the balance between ERα and ERβ in the Shell Gland, co-occurring with a dramatic drop in duodenal CA activity, are suggested as possible factors involved in age-related changes in Shell and bone quality.
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effects of phytoestrogen supplementation in the feed on the Shell Gland of laying hens at the end of the laying period
Animal Reproduction Science, 2012Co-Authors: Anna Wistedt, Yvonne Ridderstråle, Helena Wall, Lena HolmAbstract:Shell quality decreases as laying hens age and the aim of present study was to investigate how a supplement of daidzein, a natural phytoestrogen in soya, affects key factors in the Shell Gland and eggShell quality in late-stage laying hens. Hybrids of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB), received either a daidzein diet (50 mg/kg feed) or a control diet from 60 to 72 weeks of age. Both the total number of capillaries and capillaries with carbonic anhydrase (CA) activity were higher in the LSL hybrid than in the LB. After daidzein supplementation the number of CA positive capillaries was unaffected in the LSL but increased in the LB hybrid indicating a higher sensitivity to daidzein in this hybrid. Estrogen receptor alpha and beta (ERα, ERβ) were localized and the complete picture of the two ERs can now be described in Shell Gland of domestic hens. Nuclear and cytoplasmic staining was generally stronger for ERβ, while membrane associated staining was present only for ERα. Interestingly, capillary endothelium contained only ERβ and since estrogen regulation of CA is well documented, the presence of an endothelial ER provides one possible route for the increase in CA positive capillaries found in LB hybrids. EggShell quality or egg production was not affected by daidzein supplementation. The hybrids used in this study showed anatomical differences and reacted differently to daidzein supplementation, but if this can be explained by the divergences in ERβ localization noted between the hybrids remains to be clarified.
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embryonic exposure to o p ddt causes eggShell thinning and altered Shell Gland carbonic anhydrase expression in the domestic hen
Environmental Toxicology and Chemistry, 2006Co-Authors: Lena Holm, Björn Brunström, Yvonne Ridderstråle, Ingvar Brandt, Alexandra Blomqvist, Cecilia BergAbstract:The mechanism for contaminant-induced eggShell thinning in wild birds remains to be clarified. It is generally assumed, however, that it results from exposure of the adult laying female. We have reported that embryonic exposure to the synthetic estrogen ethynylestradiol (EE2) results in eggShell thinning in the domestic hen. The objective of this study was to investigate whether eggShell thinning can be induced following in ovo exposure to a bioaccumulating estrogenic environmental contaminant, o,p′-DDT. Ethynylestradiol was used as a positive control. Domestic hens exposed in ovo to o,p′-DDT (37 or 75 μg/g egg) or EE2 (60 ng/g egg) laid eggs with thinner Shells than the control birds. The hens from these exposure groups also had a significantly reduced frequency of Shell Gland capillaries with carbonic anhydrase (CA) activity, a key enzyme in eggShell formation. The decreased number of capillaries with CA activity suggests that a developmentally induced disruption of CA expression in the Shell Gland was involved in the eggShell thinning found in this study. Egg laying was not affected in hens exposed embryonically to 37 or 75 μg o,p′-DDT/g egg, whereas it was inhibited in hens exposed to higher doses. Decreased lengths of the left oviduct and its infundibulum were seen after embryonic treatment with o,p′-DDT or EE2. In addition, o,p′-DDT exposure resulted in right oviduct retention. The results support our hypothesis that eggShell thinning in avian wildlife can result from a functional malformation in the Shell Gland, induced by embryonic exposure to estrogenic substances.
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embryonic exposure to oestrogen causes eggShell thinning and altered Shell Gland carbonic anhydrase expression in the domestic hen
Reproduction, 2004Co-Authors: Cecilia Berg, Lena Holm, Björn Brunström, Ingvar Brandt, Alexandra Blomqvist, Yvonne RidderstråleAbstract:EggShell thinning among wild birds has been an environmental concern for almost half a century. Although the mechanisms for contaminant-induced eggShell thinning are not fully understood, it is generally conceived to originate from exposure of the laying adult female. Here we show that eggShell thinning in the domestic hen is induced by embryonic exposure to the synthetic oestrogen ethynyloestradiol. Previously we reported that exposure of quail embryos to ethynyloestradiol caused histological changes and disrupted localization of carbonic anhydrase in the Shell Gland in the adult birds, implying a functional disturbance in the Shell Gland. The objective of this study was to examine whether in ovo exposure to ethynyloestradiol can affect eggShell formation and quality in the domestic hen. When examined at 32 weeks of age, hens exposed to ethynyloestradiol in ovo (20 ng/g egg) produced eggs with thinner eggShells and reduced strength (measured as resistance to deformation) compared with the controls. These changes remained 14 weeks later, confirming a persistent lesion. Ethynyloestradiol also caused a decrease in the number of Shell Gland capillaries and in the frequency of Shell Gland capillaries with carbonic anhydrase activity. These data suggested that a disrupted carbonic anhydrase expression was involved in the mechanism for the oestrogen-induced eggShell thinning found in this study. The results support our hypothesis that eggShell thinning in avian wildlife can result from a structural and functional malformation in the Shell Gland, induced by xeno-oestrogen exposure during embryonic development.