Browsing by Author "Dharmendra Sharma"

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Corticosterone- or metapyrone-induced alterations in adrenal function and expression of the arginine vasotocin receptor VT2 in the pituitary gland of domestic fowl, Gallus gallus
(Academic Press Inc., 2009) Dharmendra Sharma; Lawrence E. Cornett; Chandra Mohini Chaturvedi
The avian neurohypophyseal hormone arginine vasotocin (AVT) is known to be involved in the regulation of adrenocorticotropin (ACTH) release by interacting with the VT2 receptor (VT2R), which is homologous to the mammalian vasopressin V1b receptor (V1bR). To study the role of glucocorticoid in the expression and regulation of the VT2R, corticosterone (1 or 5 mg/bird/day) or metapyrone (10 or 50 mg/kg body weight/day) were administered daily for 8 days to white leghorn chickens. While low doses were ineffective, a high dose of corticosterone upregulated, while metapyrone downregulated, pituitary VT2R mRNA expression and ir-VT2 in the cephalic lobe of the anterior pituitary. Further, although no change was observed in the expression of POMC mRNA, adrenal activity (as judged by the changes in total cholesterol, 3β HSD, cortical cord width and cortico-medullary ratio) exhibited suppression or stimulation following treatment with corticosterone or metapyrone, respectively. In view of the classical negative feedback effect of glucocorticoids at the level of hypothalamic CRH neurons and pituitary corticotrophs, high corticosterone level-induced suppression of the CRH-ACTH axis may have been masked by VT2R-mediated stimulation of corticotrophs, and hence the POMC mRNA level did not change. The same argument could be used for metapyrone. It is concluded that expression of the VT2 receptor is regulated by glucocorticoids in chicken. These findings confirm a role for AVT, mediated by the VT2 receptor, in regulating ACTH secretion during stress and suggest that corticotroph VT2 receptor levels may be dynamically regulated depending on the HPA axis activity. © 2009 Elsevier Inc. All rights reserved.
Effects of thyroid status on arginine vasotocin receptor VT2R expression and adrenal function in osmotically stimulated domestic fowl
(2009) Dharmendra Sharma; Chandra Mohini Chaturvedi
The role of thyroid hormones in the regulation of adrenal function during stress has been documented in mammals, but only limited reports are available in avian species. The present study was undertaken to analyze the effect of hyper- or hypothyroidism on the adrenal activity under control (hydrated) and osmotically stressed (water deprived, WD) conditions, with special emphasis on the expression of arginine vasotocin receptor VT2 (VT2R) in pituitary corticotrophs. Chickens were made hyper- or hypothyroidic by injecting thyroxine (T4) and 2-thiouracil (TU), respectively for 14 days. After 10 days of injections, one sub-group of both, T4- or TU-treated chickens were subjected to osmotic stress by water deprivation. Hyperthyroidism stimulated adrenal steroidogenic activity compared to euthyroid control birds, but no change was observed in the expression of VT2R. On the other hand, TU-induced hypothyroidism however showed no effect on adrenal gland, but a significant increase in the expression of VT2R was observed. Neither hyper- nor hypothyroidism altered pro-opiomelanocortin (POMC) mRNA levels. Following osmotic stress, no effect was observed either on the adrenal gland or on the VT2R expression in hyperthyroidic birds, but in hypothyroidic birds, osmotic stress stimulated adrenal steroidogenic activity and decreased VT2R expression in comparison to its respective controls (T4 or TU). Expression of POMC mRNA was again unaltered following osmotic stress. Although exact mechanism is not clear, the data indicate that high plasma T4 level stimulates adrenal activity and may also modulate function of the pituitary-adrenal axis during dehydration. © Springer-Verlag 2009.
Osmotic stress induced alteration in the expression of arginine vasotocin receptor VT2 in the pituitary gland and adrenal function of domestic fowl
(Academic Press Inc., 2009) Dharmendra Sharma; Lawrence E. Cornett; Chandra Mohini Chaturvedi
The role of arginine vasotocin in the regulation of the pituitary-adrenal axis of domestic fowl was analyzed by studying the expression of its recently cloned pituitary receptor VT2 and adrenal activity following osmotic stress. Four days of water deprivation induced an increase in plasma osmolality-a known stimulator of AVT synthesis and release from hypothalamic magnocellular neurons. Water deprivation also decreased pituitary mRNA levels for both the VT2 receptor and for pro-opiomelanocortin (POMC). Despite a decrease in the expression of VT2 mRNA, immunoreactive-VT2 receptor levels in the pituitary increased, suggesting a possible role for post-transcriptional mechanisms in the regulation of this receptor. Further, adrenal activity (as judged by adrenal weight, cholesterol content, 3β hydroxysteroid dehydrogenase, cortical cord width and cortico-medullary ratio) showed stimulation in water-deprived chicken as compared to control. On the basis of present findings, it is concluded that water deprivation down regulates the mRNA expression of AVT receptor VT2 as well as POMC but stimulates adrenal function. It is also suggested that in addition to the release of magnocellular AVT into the neurohypophysis to act as antidiuretic hormone following water deprivation, AVT may also modulate HPA axis to cope with the osmotic stress. © 2008 Elsevier Inc.
PRAYAS: individual patient data meta-analysis database for Pooled Research and Analysis for Yielding Anemia-free Solutions in India
(Frontiers Media SA, 2025) Anuj Kumar Pandey; Anju Pradhan Sinha; Ramu Rawat; Ranadip Chowdhury; Shivaprasad S. Goudar; Jitender Nagpal; Shrey A. Desai; Avula Laxmaiah; Basany Kalpana; Sadhana Ramchandra Joshi; Chittaranjan Sakerlal Yajnik; Aparna Mukherjee; Pratibha K. Dwarkanath; Priyanka Gupta Bansal; Molly Jacob; Shinjini Bhatnagar; Komal H. Shah; Debarati Mukherjee; Amlin Shukla; Raghu Pullakhandam; Varsha S. Dhurde; Aditi A. Apte; Rajeev Kumar Singh; Aakriti Gupta; Yamini Priyanka; Usha Dhingra; Ravi Prakash Upadhyay; Sutapa Bandyopadhyay B Neogi; Manjunath Somappa Somannavar; Anirban N. Mandal; Gayatri Desai; Shantanu Sengupta; Shailendra Dandge; Girija Narendrakumar Wagh; Urmila S. Deshmukh; Gunjan Kumar; Anura Vishwanath Kurpad; Gurudayal Singh Toteja; Nikhitha Mariya John; Shailaja Sopory; Somen Saha; Giridhar R. Babu; Anandika Suryavanshi; Ravindranadh Palika; Archana Behram Patel; Radhika K. Nimkar; Gaurav Raj Dwivedi; Umesh S. Kapil; Dilip Raja; Arup Dutta; Sunita Taneja; Diksha Gautam; Avinash Kavi; Swapnil Rawat; Kapil Dave; Rajiva Raman; Catherine L. Haggerty; Sanjay Kewalchand Lalwani; Prachi Ravindra Phadke; Alka Turuk; Tinku S. Thomas; Neena Bhatia; Manisha Madai Beck; Lovejeet Kaur; Aakansha Shukla; Ravi Deepa; Lindsey Mina Locks; Dhiraj M. Agarwal; Raja Sriswan Mamidi; Harshpal Singh Sachdev; Rounik Talukdar; Sayan Das; Nita Bhandari; Ranjana A. Singh; S. Yogeshkumar; Ramasheesh Yadav; Purushotham Sudhakar Reddy; Sanjay A. Gupte; S. Rasika Ladkat; Zaozianlungliu Gonmei; Swati Rathore; Dharmendra Sharma; Apurva Kumar Pandya; Yamuna Ana; Patricia L. Hibberd; Himangi Govind Lubree; Anwar Basha Dudekula; Priti Rishi Lal; Pearlin Amaan Khan; Aruna Verma; Umesh S. Charantimath; Indrapal Ishwarji Meshram; Karuna N. Randhir; Onkar Deshmukh; Ashok Kumar Roy; Obed John; Nolita Dolcy Saldanha; Ashish R. Bavdekar; Raj Kumar; Shyam Prakash
Purpose: The PRAYAS Individual Patient Data Meta-analysis (IPD-MA) database aims to estimate the prevalence of anemia among children under 18 years, non-pregnant and non-lactating (NPNL) women, and pregnant women (by trimester), with further stratification by age group, year, and region of India. Beyond prevalence, it seeks to address the etiological contribution of iron and other erythropoietic micronutrient deficiencies and to evaluate the effectiveness of anemia prevention and treatment interventions, including factors associated with non-response. This will directly support India’s “test–treat–track” approach under the Anemia Mukt Bharat program. Participants: Children (0–18 years), pregnant women, and NPNL women in India. Findings to date: The database currently includes 88 datasets (1994–2023), with 319,721 participants for prevalence analysis—children (19,762), NPNL women (17,883), and pregnant women (282,076). Intervention studies comprise 59,292 participants—children (13,435), NPNL women (11,594), and pregnant women (34,263). Over half the datasets (55.7%, 49/88) are randomized controlled trials, while 35.2% (31/88) are observational. Geographically, 43.2% (38/88) are from northern India, 22.7% (20/88) from the west, and 18.2% (16/88) from the south. Most studies (67%, 59/88) are community-based. Median ages were 26 years (IQR 23–32) for NPNL and 23 years (IQR 21–25) for pregnant women, while children’s data covered 6 months to 18 years. Mean gestational age at enrollment in pregnancy was 10.24 weeks (SD 17.65). Of the total sample, 10.8% had complete blood count data, 9% ferritin, and 4.5% vitamin B12. Among interventions, pregnant women received intravenous iron sucrose, ferric carboxymaltose, iron isomaltoside, combined IV iron with vitamin B12/folic acid/niacinamide, integrated packages, and low-dose calcium supplementation. NPNL women were often part of trials comparing 60 mg daily ferrous sulfate with 120 mg on alternate days. Children’s interventions mainly included ferrous sulfate, food supplementation, and select Ayush-based approaches. Future plans: PRAYAS will generate robust, policy-relevant evidence to refine anemia prevention and treatment strategies. Findings will directly inform the Anemia Mukt Bharat program, supporting targeted, evidence-driven interventions to reduce anemia and associated health burdens across children, women, and pregnant populations in India. Clinical Trial Registration: OSF—https://doi.org/10.17605/OSF.IO/6YRXF. © © 2025 Pandey, Sinha, Rawat, Chowdhury, Goudar, Nagpal, Desai, Laxmaiah, Basany, Joshi, Yajnik, Mukherjee, Dwarkanath, Bansal, Jacob, Bhatnagar, Shah, Mukherjee, Shukla, Pullakhandam, Dhurde, Apte, Singh, Gupta, Priyanka, Dhingra, Upadhyay, Neogi, Somannavar, Mandal, Desai, Sengupta, Dandge, Wagh, Deshmukh, Kumar, Kurpad, Toteja, John, Sopory, Saha, Babu, Suryavanshi, Palika, Patel, Nimkar, Dwivedi, Kapil, Raja, Dutta, Taneja, Gautam, Kavi, Rawat, Dave, Raman, Haggerty, Lalwani, Phadke, Turuk, Thomas, Bhatia, Beck, Kaur, Shukla, Deepa, Locks, Agarwal, Mamidi, Sachdev, Talukdar, Das, Bhandari, Singh, Yogeshkumar, Yadav, Reddy, Gupte, Ladkat, Gonmei, Rathore, Sharma, Pandya, Ana, Hibberd, Lubree, Dudekula, Lal, Khan, Verma, Charantimath, Meshram, Randhir, Deshmukh, Roy, John, Saldanha, Bavdekar, Kumar, Prakash, Fawzi and Sazawal.
Testosterone modulates pituitary vasotocin receptor expression and adrenal activity in osmotically stressed chicken
(Elsevier Inc., 2011) Dharmendra Sharma; Chandra Mohini Chaturvedi
Regulation of arginine vasotocin (AVT), avian neurohypophyseal hormone, is an important component of the hypothalamo-pituitary-adrenal axis. Changes in plasma osmolality levels and sex steroids are known to affect AVT gene expression. The present study reports the effect of water deprivation and testosterone treatment independently, as well as simultaneously, on the pituitary vasotocin receptor VT2R expression and adrenal steroidogenic activity in sexually immature male chicken (Gallus gallus). Birds were divided into four groups- control, water deprived (WD), testosterone injected (TE) and TE treated water deprived (TE. +. WD). WD decreased and TE treatment alone or in combination with WD (TE. +. WD) increased VT2R expression compared to the control. Expression of pro-opiomelanocortin (POMC) was also studied since this gene is a polypeptide precursor of ACTH and is under the negative feedback of adrenal corticoids. TE treatment as well as WD separately or when coupled together decreased the POMC mRNA expression in the pituitary but stimulated adrenal steroidogenic activity. Further, VT2R expression decreased in TE. +. WD compared to TE group, but it was not different from the vehicle treated control group suggesting that the suppressive effect of WD on VT2R expression was inhibited by the stimulatory effect of testosterone. Similarly, although both TE and WD decreased POMC expression and increased steroidogenic activity, no further decrease or increase in these parameters was observed when these two (WD and TE) treatments were combined together. Although, the exact mechanism is not clear, data indicate a stimulatory action of testosterone on VT2R expression and adrenal function despite a decreased expression of POMC mRNA. Results also suggest that testosterone treatment to sexually immature birds, in addition to its effect on hypothalamic AVT neurons (earlier study) and pituitary VT2R expression (present study), masks or inhibits osmotic stress-induced alterations in pituitary-adrenal activity. © 2010 Elsevier Inc.