Factors Affecting Nitrate Reductase Activity in Some Monocot and Dicot Species

Chanda, Sumitra V. 한국식물학회 2003 Journal of Plant Biology Vol.46 No.1

Activity of nitrate reductase (NR), the first enzyme in the nitrate-assimilation pathway, was estimated in the cotyledons of the sunflower (Helianthus annuus) using a standardized in-vivo method. Seedlings were grown in the light on a nitrate medium. Various factors that affect NR activity were optimized, including the molarity and pH of the reaction buffer, nitrate concentration, and use of a surfactant. We also determined whether NADH was required for nitrate reduction. The surfactant propanol (2%) gave the best results, and no NADH supplement was necessary. In a separate study, we compared the effect of various culturing components on in-vivo NR activity among monocot and dicot species, and found that Triton X-100 was the best surfactant for monocots whereas dicots performed better with n-propanol. Monocot species also required additional NADH as an external energy source. Moreover, specific purification procedures were needed to enhaned NR activity in dicotyledons. Finally, we also assessed the efficacy of in-vivo versus in-vitro procedures for assaying monocots versus dicots.

Fenofibrate differentially regulates plasminogen activator inhibitor‐1 gene expression via adenosine monophosphate–activated protein kinase–dependent induction of orphan nuclear receptor small heterodimer partner

Chanda, Dipanjan,Lee, Chul Ho,Kim, Yong‐,Hoon,Noh, Jung‐,Ran,Kim, Don‐,Kyu,Park, Ji‐,Hoon,Hwang, Jung Hwan,Lee, Mi‐,Ran,Jeong, Kyeong‐,Hoon,Lee, In‐,Kyu,Kweon Wiley Subscription Services, Inc., A Wiley Company 2009 Hepatology Vol.50 No.3

<P><B>Abstract</B></P><P>Plasminogen activator inhibitor type I (PAI‐1) is a marker of the fibrinolytic system and serves as a possible predictor for hepatic metabolic syndromes. Fenofibrate, a peroxisome proliferator‐activated receptor α (PPARα) agonist, is a drug used for treatment of hyperlipidemia. Orphan nuclear receptor small heterodimer partner (SHP) plays a key role in transcriptional repression of crucial genes involved in various metabolic pathways. In this study, we show that fenofibrate increased SHP gene expression in cultured liver cells and in the normal and diabetic mouse liver by activating the adenosine monophosphate–activated protein kinase (AMPK) signaling pathway in a PPARα‐independent manner. Administration of transforming growth factor beta (TGF‐β) or a methionine‐deficient and choline‐deficient (MCD) diet to induce the progressive fibrosing steatohepatitis model in C57BL/6 mice was significantly reversed by fenofibrate via AMPK‐mediated induction of SHP gene expression with a dramatic decrease in PAI‐1 messenger RNA (mRNA) and protein expression along with other fibrotic marker genes. No reversal was observed in SHP null mice treated with fenofibrate. Treatment with another PPARα agonist, WY14643, showed contrasting effects on these marker gene expressions in wild‐type and SHP null mice, demonstrating the specificity of fenofibrate in activating AMPK signaling. Fenofibrate exhibited a differential inhibitory pattern on PAI‐1 gene expression depending on the transcription factors inhibited by SHP. <I>Conclusion:</I> By demonstrating that a PPARα‐independent fenofibrate‐AMPK‐SHP regulatory cascade can play a key role in PAI‐1 gene down‐regulation and reversal of fibrosis, our study suggests that various AMPK activators regulating SHP might provide a novel pharmacologic option in ameliorating hepatic metabolic syndromes. (H<SMALL>EPATOLOGY</SMALL> 2009.)</P>

Perspective Towards Women’s Sexuality in Nepal

Chanda Devi SUNAR 이화여자대학교 아시아여성학센터 2018 이화여자대학교 아시아여성학센터 학술대회자료집 Vol.2018 No.1

Sexuality is an inevitable part of human life; its about expressing oneself as sexual being. It is about conveying innate attributes such as sexual desires, roles, identities and orientations. According to World Health Organization (WHO), sexuality is a central aspect of being human throughout life and encompasses sex, gender identities and roles, sexual orientation, eroticism, pleasure, intimacy and reproduction. Sexuality is experienced and expressed in thoughts, fantasies, desires, beliefs, values, behaviours, practices, roles and relationships. As the definition suggests sexuality is every human beings strong need and desire. However, in the contest of South Asian countries like Nepal the power of sexuality is only limited to men and women are only the victims of mens sexuality. We can see that control of womens bodies and sexuality has been one of the central concerns of all major civilizations. Nepal, a historically and predominantly patriarchal society, has culturally prescribed codes and behavioural norms for women that focus on modesty and fidelity, emphasizing, apart from a few exceptions, firstly virginity and later chastity, which are valued above all other qualities in women. In this paper, I have included some major concerns of sexuality and women’s empowerment in relation to the social construction of Nepal, its understanding and practices. Also, I have highlighted the connection between sexuality and empowerment, responsibility of state towards the issue of sexuality, positive steps in legislation and way forward with recommendation.

Identification of Promising Bivoltine Breeds based on Multiple Trait Analysis for Future Breeding Program in West Bengal, India

Chanda, Subhra,Saha, Lal Mohan,Das, Nirvan Kumar,Kar, Niharendu Bikash,Bindroo, Bharat Bhusan Korean Society of Sericultural Science 2011 International Journal of Industrial Entomology Vol.23 No.2

Thirty five bivoltine breeds were acclimatized under controlled condition for three years during two seasons to evaluate their efficiency in Seri industry of tropical region. Out of thirty five ten breeds had been short listed based on ranking for individual trait. Three breeds out of those ten selected breeds viz. SK6, NB18 and B.Con.4 ranked top in respect of overall performance. The ten breeds based on average Evaluation Index value > 50 considering twelve economically important traits are the resource material for future course of breeding program in West Bengal.

Activation of Cannabinoid Receptor Type 1 (<i>Cb1r</i>) Disrupts Hepatic Insulin Receptor Signaling via Cyclic AMP-response Element-binding Protein H (<i>Crebh</i>)-mediated Induction of<i>Lipin1</i>Gene

Chanda, Dipanjan,Kim, Yong-Hoon,Kim, Don-Kyu,Lee, Min-Woo,Lee, Su-Yeon,Park, Tae-Sik,Koo, Seung-Hoi,Lee, Chul-Ho,Choi, Hueng-Sik American Society for Biochemistry and Molecular Bi 2012 The Journal of biological chemistry Vol.287 No.45

Sodium arsenite induces orphan nuclear receptor SHP gene expression via AMP-activated protein kinase to inhibit gluconeogenic enzyme gene expression.

Chanda, Dipanjan,Kim, Sung-Jin,Lee, In-Kyu,Shong, Minho,Choi, Hueng-Sik American Physiological Society 2008 AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND M Vol.295 No.2

<P>Sodium arsenite has been demonstrated to alter the expression of genes associated with glucose homeostasis in tissues involved in the pathogenesis of type 2 diabetes; however, the underlying molecular mechanism has not been fully elucidated yet. In this study, we report that the sodium arsenite-induced gene expression of the small heterodimer partner (SHP; NR0B2), an atypical orphan nuclear receptor, regulates the expression of hepatic gluconeogenic genes. Sodium arsenite augments hepatic SHP mRNA levels in an AMP-activated protein kinase (AMPK)-dependent manner. Sodium arsenite activated AMPK and was shown to perturb cellular ATP levels. The arsenite-induced SHP mRNA level was blocked by adenoviral overexpression of dominant negative AMPK (Ad-dnAMPKalpha) or by the AMPK inhibitor compound C in hepatic cell lines. We demonstrated the dose-dependent induction of SHP mRNA levels by sodium arsenite and repressed the forskolin/dexamethasone-induced gene expression of the key hepatic gluconeogenic genes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase). Ad-dnAMPKalpha blocked the repressive effects of arsenite-induced SHP on PEPCK and G6Pase. Sodium arsenite inhibited the promoter activity of PEPCK and G6Pase, and this repression was abolished by small interfering (si)RNA SHP treatments. The knockdown of SHP expression by oligonucleotide siRNA SHP or adenoviral siRNA SHP released the sodium arsenite-mediated repression of forskolin/dexamethasone-stimulated PEPCK and G6Pase gene expression in a variety of hepatic cell lines. Results from our study suggest that sodium arsenite induces SHP via AMPK to inhibit the expression of hepatic gluconeogenic genes and also provide us with a novel molecular mechanism of arsenite-mediated regulation of hepatic glucose homeostasis.</P>

Hepatocyte growth factor family negatively regulates hepatic gluconeogenesis via induction of orphan nuclear receptor small heterodimer partner in primary hepatocytes.

Chanda, Dipanjan,Li, Tiangang,Song, Kwang-Hoon,Kim, Yong-Hoon,Sim, Jeonggu,Lee, Chul Ho,Chiang, John Y L,Choi, Hueng-Sik American Society for Biochemistry and Molecular Bi 2009 The Journal of biological chemistry Vol.284 No.42

<P>Hepatic gluconeogenesis is tightly balanced by opposing stimulatory (glucagon) and inhibitory (insulin) signaling pathways. Hepatocyte growth factor (HGF) is a pleiotropic growth factor that mediates diverse biological processes. In this study, we investigated the effect of HGF and its family member, macrophage-stimulating factor (MSP), on hepatic gluconeogenesis in primary hepatocytes. HGF and MSP significantly repressed expression of the key hepatic gluconeogenic enzyme genes, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (Glc-6-Pase) and reduced glucose production. HGF and MSP activated small heterodimer partner (SHP) gene promoter and induced SHP mRNA and protein levels, and the effect of HGF and MSP on SHP gene expression was demonstrated to be mediated via activation of the AMP-activated protein kinase (AMPK) signaling pathway. We demonstrated that upstream stimulatory factor-1 (USF-1) specifically mediated HGF effect on SHP gene expression, and inhibition of USF-1 by dominant negative USF-1 significantly abrogated HGF-mediated activation of the SHP promoter. Elucidation of the mechanism showed that USF-1 bound to E-box-1 in the SHP promoter, and HGF increased USF-1 DNA binding on the SHP promoter via AMPK and DNA-dependent protein kinase-mediated pathways. Adenoviral overexpression of USF-1 significantly repressed PEPCK and Glc-6-Pase gene expression and reduced glucose production. Knockdown of endogenous SHP expression significantly reversed this effect. Finally, knockdown of SHP or inhibition of AMPK signaling reversed the ability of HGF to suppress hepatocyte nuclear factor 4alpha-mediated up-regulation of PEPCK and Glc-6-Pase gene expression along with the HGF- and MSP-mediated suppression of gluconeogenesis. Overall, our results suggest a novel signaling pathway through HGF/AMPK/USF-1/SHP to inhibit hepatic gluconeogenesis.</P>

Detection of Antistaphylococcal and Toxic Compounds by Biological Assay Systems Developed with a Reporter Staphylococcus aureus Strain Harboring a Heat Inducible Promoter - lacZ Transcriptional Fusion

Chanda, Palas Kumar,Ganguly, Tridib,Das, Malabika,Lee, Chia Yen,Luong, Thanh T.,Sau, Subrata Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.6

Previously it was reported that promoter of groES-groEL operon of Staphylococcus aureus is induced by various cellwall active antibiotics. In order to exploit the above promoter for identifying novel antistaphylococcal drugs, we have cloned the promoter containing region ($P_g$) of groES-groEL operon of S. aureus Newman and found that the above promoter is induced by sublethal concentrations of many antibiotics including cell-wall active antibiotics. A reporter S. aureus RN4220 strain (designated SAU006) was constructed by inserting the $P_g$-lacZ transcriptional fusion into its chromosome. Agarose-based assay developed with SAU006 shows that $P_g$ in single-copy is also induced distinctly by different classes of antibiotics. Data indicate that ciprofloxacin, rifampicin, ampicillin, and cephalothin are strong inducers, whereas, tetracycline, streptomycin and vancomycin induce the above promoter weakly. Sublethal concentrations of ciprofloxacin and ampicilin even have induced $P_g$ efficiently in microtiter plate grown SAU006. Additional studies show for the first time that above promoter is also induced weakly by arsenate salt and hydrogen peroxide. Taken together, we suggest that our simple and sensitive assay systems with SAU006 could be utilized for screening and detecting not only novel antistaphylococcal compounds but also different toxic chemicals.

Quantification of the digestive proteases and lipase of Schizodactylus monstrosus after the treatment of an organophosphorus insecticide, phosphamidon.

Chanda, Subhra,Roy, S. 한국곤충학회 1986 Korean journal of entomology Vol.16 No.1

This communication presents the results of an experimental study with phosphamidon on the digestive proteases and lipase of Schizodactytus monstrosus. The enzymes estimated are the protease, trypsin, chymotrypsin and lipase in the gut lumen and gut tissue of the insect, Both the treated and control females show significantly greater activity than male individuals. The enzymes exhibit varying results following the treatments with phosphamidon which depends upon the exposure-time. All the enzymes of both sexes show optimal activities in the treated specimens after 6 hours of treatment with phosphamidon. Although the activity of each enzyme increased in each of the gut fraction (fore, mid and hind) of both sexes yet some quantitative differences among them have been noticed. Gradual and significant declining effects have also been found after 12 hrs., 18 hrs. and 24 hrs. of treatment. The activities observed after 24 hours exposure of phosphamidon treatment appeared significantly low when compared to control. The most interesting observation is that this is true in case of all enzymes irrespective of sex and gut fraction. The physiological significance of these results are discussed in relation to the control of enzyme secretion and synthesis.

Correlation among Shell Percent, Cocoon Yield and Reeling Parameters of Multi × Bi Cocoons under Different Agro-Climatic Conditions of West Bengal, India

Chanda, Subhra,Saha, Lal Mohan,Das, Nirvan Kumar,Kar, Niharendu Bikash,Bindroo, Bharat Bhusan Korean Society of Sericultural Science 2013 International Journal of Industrial Entomology Vol.26 No.2

Three new Multi ${\times}$ Bi combinations M.Con.4 ${\times}$ (SK6 ${\times}$ SK7), M.Con.4 ${\times}$ NB4D2 and Nistari ${\times}$ (SK6 ${\times}$ SK7) were studied in five seasons i.e. during the period of $18^{th}$ June - $12^{th}$ July, $30^{th}$ August - $23^{rd}$ September, $3^{rd}$ November - $2^{nd}$ December, $29^{th}$ January- $2^{nd}$ March and $30^{th}$ March-$25^{th}$ April with one control Nistari ${\times}$ NB4D2 considering nine reeling characteristics along with shell percent and cocoon yield per 100 disease free layings (DFLs) to establish the seasonal effect on all the parameters. Results reveal that all the characters performed well in November-December. Highest yield per 100 DFLs was recorded during November-December in all combinations showing >60 kg yield. Higher correlation of yield/100 DFLs with filament length, non-breakable filament length, denier, raw silk percent, reelability percent and recovery percent was recorded in all combinations of Multi ${\times}$ Bi considered in this study. Variability observed among four combinations indicates the effect of different temperature and humidity of different seasons on expression of different traits. The results indicate that there is significant relationship of raw silk percent with reelability percent, recovery percent and evenness. Reelability percent showed higher correlation with recovery percent. It was observed that neatness was positively correlated with evenness. The overall performance of the newly evolved combinations with regard to productivity and reeling characteristics is discussed emphasizing their utilization at commercial level.