Browsing by Author "Rahul Kumar Singh"

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A comparison of steroid profiles in the testis and seminal vesicle of the catfish (Heteropneustes fossilis)
(Elsevier Inc., 2018) Radha Chaube; Surabhi Mishra; Rahul Kumar Singh
In the present study, distribution of steroid hormones (estradiol-17β (E2), testosterone (T), corticosteroids and progestins) in the testis and seminal vesicles (SV) of the catfish Heteropneustes fossilis were investigated in two seasons (pre-spawning and spawning phases) of the reproductive cycle. The data showed that the levels of the steroid hormones varied significantly in both reproductive phases and exhibited organ-related differences. Sex steroid levels were highest in the pre-spawning phase and lowest in the spawning phase. The concentration of E2 and cortisol was highest in the testis. However, E2 level was higher in the SV compared to the testis in the pre-spawning phase and during spawning phase there was no significant difference in the E2 level of testis and SV. Seminal vesicle and testis recorded higher levels of cortisol in the spawning phase. The concentration of corticosterone was significantly higher in testis during pre-spawning phase and in seminal vesicle during the spawning phase. 21-deoxycortisol was higher in the pre-spawning phase in the SV but not in the testis and deoxycorticosterone was significantly higher in the pre-spawning phase than spawning phase. Progesterone was high in the pre-spawning phase and low in all tissues in the spawning phase. 17-P4 concentration was the highest in both SV and testis during spawning phase. In the testis 17, 20β-DP concentration was the highest in the pre-spawning phase. In contrast, in the SV, 17, 20β-DP was lowest during pre-spawning phase. This study shows high levels of corticosteroid profile in the testis and SV. The physiological significance of the steroids other than T is not clear at present. However, knowledge of seasonal profile of key steroid hormones in the male catfish may be helpful in monitoring reproductive capability and important for fish breeding in captivity. © 2017 Elsevier Inc.
A holistic review on trend, occurrence, factors affecting pesticide concentration, and ecological risk assessment
(Springer Science and Business Media Deutschland GmbH, 2023) Rajeev Pratap Singh; Monika Mahajan; Kavita Gandhi; Pankaj Kumar Gupta; Anita Singh; Prafull Singh; Rahul Kumar Singh; Mohd Kashif Kidwai
Demographic outbursts and increased food demands invoke excessive use of pesticides in the agricultural field for increasing productivity which leads to the relentless decline of riverine health and its tributaries. These tributaries are connected to a plethora of point and non-point sources that transport pollutants including pesticides into the Ganga river’s mainstream. Simultaneous climate change and lack of rainfall significantly increase pesticide concentration in the soil and water matrix of the river basin. This paper is intended to review the paradigm shift of pesticide pollution in the last few decades in the river Ganga and its tributaries. Along with this, a comprehensive review suggests the ecological risk assessment method which facilitates policy development, sustainable riverine ecosystem management, and decision-making. Before 2011, the total mixture of Hexachlorocyclohexane was found at 0.004–0.026 ng/mL in Hooghly, but now, the concentration has increased up to 0.465–4.132 ng/mL. Aftermath of critical review, we observed maximum residual commodities and pesticide contamination reported in Uttar Pradesh > West Bengal > Bihar > Uttara Khand possibly because of agricultural load, increasing settlement, and incompetency of sewage treatment plant in the reclamation of pesticide contamination. Graphical Abstract: [Figure not available: see fulltext.] © 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
An insight into the molecular mechanisms of persistent organic pollutants (POPs) mediated dysregulation of glucose and lipid homeostasis in Heteropneustes fossilis
(Academic Press Inc., 2025) Shubhendu Shekhar Ray; Archisman Mahapatra; Priya Gupta; Anjali Suman; Rahul Kumar Singh
The study emphasises how ubiquitous persistent organic pollutants (POPs) are and how terrible they are for the environment, specifically because of their tendency to build up in living things and cause a variety of health problems, including diabetes, obesity, and cardiovascular disorders. Due to POPs affinity for lipid-rich tissues, they accumulate in a variety of organs, where they cause metabolic disruption and initiate various anabolic pathways. Studies that use fish as a model organism clarify the metabolic effects of POPs, demonstrating non-adipose lipid accumulation and abnormal glucose homeostasis. Further research on molecular mechanisms shows that POPs interact with gluconeogenic enzymes, causing blood glucose levels to rise. These results are supported by histological and biochemical examinations of fish exposed to POPs, which show changes in lipid composition and cause cellular damage. Molecular docking computational studies demonstrate POPs propensity for binding to gluconeogenic enzymes, providing insight into their potential to promote hyperglycaemia. This study provides a thorough summary of POPs harmful effects on organisms, highlighting their molecular and toxicological, impacts while arguing for better knowledge of their toxicity to vertebrates’ developing embryos. © 2025 Elsevier Inc.
Changes in vasotocin levels in relation to ovarian development in the catfish Heteropneustes fossilis exposed to altered photoperiod and temperature
(Kluwer Academic Publishers, 2015) Radha Chaube; Rahul Kumar Singh; Keerikattil P. Joy
Photoperiod and temperature are the major proximate factors that activate the brain–pituitary–gonadal–endocrine axis stimulating gonadal recrudescence. Vasotocin (VT), the basic nonapeptide hormone, is secreted by the nucleus preopticus in the hypothalamus and released from the pituitary into circulation as a neurohormone for physiological actions. Additionally, VT is secreted de novo in the ovary of the catfish and has been implicated in ovarian functions. In the present study, we evaluated the changes in VT secretion during altered photoperiod and temperature exposure. The ovarian changes were monitored over gonadosomatic index (GSI) and plasma steroid hormone levels. Exposure of the catfish to long photoperiod (LP, 16L:08D) daily, alone or in combination with high temperature (HT, 28 ± 2 °C), for 14 or 28 days resulted in a decrease in brain–pituitary VT level with a concomitant increase in plasma and ovarian VT levels. The changes were greater in the LP + HT group on day 28. Concurrently, the treatments stimulated the GSI and plasma estradiol-17β (E2), testosterone (T) and progesterone (P4) levels with higher more responses in the LP + HT group. Exposure of the catfish to short photoperiod (SP, 08L:16D) daily or total darkness (TD, 24L:00D) daily, with or without changing the ambient temperature, for 14 or 28 days produced a depressing effect on VT, GSI and steroid hormone levels, the range of the response varied with the temperature. The brain VT level was low except in the TD + NT group. Plasma and ovarian VT levels decreased more in the SP and TD groups under ambient temperature than in the groups at the raised temperature. The GSI and plasma steroid hormones (E2, T and P4) responded in a similar manner. Plasma cortisol level registered a significant increase in all the groups compared to the initial control groups, and the increase was significantly higher on day 28. The simultaneous activation of VT secretion and ovarian recrudescence by photoperiod and temperature suggests the peptide’s involvement in the hormonal control of gametogenesis. © 2015, Springer Science+Business Media Dordrecht.
Click inspired novel pyrazole-triazole-persulfonimide & pyrazole-triazole-aryl derivatives; Design, synthesis, DPP-4 inhibitor with potential anti-diabetic agents
(Academic Press Inc., 2022) Manisha Nidhar; Shaziya Khanam; Priyanka Sonker; Priya Gupta; Archisman Mahapatra; Swaraj Patil; Brijesh Kumar Yadav; Rahul Kumar Singh; Ashish Kumar Tewari
This work presented the first report on designing, synthesizing of novel pyrazole-triazole-persulfonimide (7a-i) and pyrazole-triazole-aryl derivatives (8a-j) via click reaction using CuI catalyst and evaluated for their anti-diabetic activity and DPP-4 inhibitory effect. Click reactions went smoothly with CuI catalyst in the presence of tridentate chelating ligands and produced copper-free target pyrazole-triazole-persulfonimide analogues in excellent yield at RT. The designed compounds were docked against DPP-4 enzyme and showed excellent interaction with active amino acids residue. Further, all novel pyrazole-triazole-persulfonimide and pyrazole-triazole derivatives were subjected to enzyme-based in vitro DPP-4 inhibitory activity. Based on the SAR study DPP-4 inhibitory capacity compounds 7f (9.52 nM) and 8h (4.54 nM) possessed the significant inhibition of DPP-4. Finally compounds 7f and 8h were evaluated for their in vivo anti-diabetic activity using STZ induced diabetic mice model, and 8h showed a significant diabetic control effect compared to the sitagliptin drug. These studies demonstrated that the novel pyrazole-triazole-persulfonimide and pyrazole-triazole-aryl derivatives might be used as the leading compounds to develop novel DPP-4 inhibitors as potential anti-diabetic agents. © 2022 Elsevier Inc.
Designing DPP-4 inhibitors: Synthesis, characterization, in silico & in vitro evaluation, and theoretical calculation of flexible compounds linked via ortho xylyl spacers
(Elsevier B.V., 2025) Vipin Kumar; Manisha Nidhar; Muhammad Sheraj; Vishal Prasad Sharma; Priya Gupta; Rahul Kumar Singh; Ashish Kumar Tewari
In this study, 1,2,3-triazole-containing six symmetrical flexible dimer compounds (5a-5f) linked via ortho xylyl spacers were synthesized using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction. Triazinone, isatin, and pyridazinone moieties were utilized to synthesize the heteroaromatic terminal alkynes (3a-3f). The structural characterization of all compounds was performed using spectroscopic techniques, including SCXRD, 1H and 13C-NMR, IR, and HRMS spectrometry. Among these compounds, compound 5a was crystallized, showing two twisted boat-type geometries at an angle of 43.98 degrees. Moreover, we investigated the intra- and intermolecular contact preserving the crystal packing in the solid state. Hirshfeld surface analysis and its related 2-D fingerprint plots control the percentage contribution of intermolecular contact. The in silico study of these compounds was conducted and revealed that 5d and 5c have good docking scores and interactions; further, all these compounds were validated by in vitro DPP-4 inhibitory activity. DPP-4 inhibition revealed that compound 5d has an IC50 value of 1.57 nM, similar to the standard drug sitagliptin. Compound 5d could be a potent DPP-4 inhibitor with antidiabetic potential for further investigation. © 2025
Differential and reproductive stage-dependent regulation of vasotocin secretion by catecholamines in the catfish Heteropneustes fossilis
(Elsevier Inc., 2013) Rahul Kumar Singh; Radha Chaube; Keerikkattil P. Joy
Vasotocin (VT) is the basic nonapeptide hormone secreted by the neurohypophysis of non-mammalian vertebrates and is involved in the regulation of osmoregulation, metabolism, cardiovascular function, reproduction and behaviour. Among the reproductive function, VT is specifically implicated in final oocyte maturation, ovulation, oviposition/parturition in teleosts, amphibians, reptiles, and birds. The central catecholaminergic system is involved in the regulation of pituitary hormone secretion including gonadotropin, and mediates also changes in environmental photoperiod and temperature. The close apposition of the VT and catecholaminergic systems in the preoptic area of the hypothalamus signifies a strong possibility of their functional interaction. The aim of the present study was to investigate the effects of exogenously administered catecholamines on VT secretion in two different reproductive phases of female catfish Heteropneustes fossilis. For this, the catecholamine precursor l-dihydroxyphenylalanine (l-DOPA) and catecholamines (dopamine-DA, norepinephrine-NE, and epinephrine-E) were intraperitoneally injected in normal catfish and/or along with α-methylparatyrosine (α-MPT, a tyrosine hydroxylase inhibitor). Brain and plasma VT levels were measured by specific ELISA, 24. h post injection. Both l-DOPA and DA inhibited brain and plasma VT levels in a concentration-dependent manner in preparatory and prespawning phases. In contrast, NE elicited dose-dependent effects: the lowest dose (0.5. ng/g body mass, BM) was ineffective, the median dose (1. ng/g BM) stimulated, and the high doses (10 and 100. ng/g BM) inhibited VT levels. E stimulated VT levels dose-dependently. A single injection of α-MPT (250. μg/g BM) strongly inhibited VT when given alone and enhanced the inhibitory effects of l-DOPA and DA in the combination groups. The α-MPT inhibition of VT was significantly reduced by the injection of NE (5. ng/g BM) and was restored or elevated by E. When the adrenergic neurotransmitters were given together with α-MPT, the inhibitory effect of the latter was abolished and VT levels were significantly elevated. Thus, the present data indicate that the physiological changes in VT is differentially regulated by the catecholamines (DA inhibits and NE/E stimulates VT). © 2013.
Elucidating the impact of persistent organic pollutants on male reproductive health and testicular structure
(Elsevier Ireland Ltd, 2025) Shubhendu Shekhar Ray; Priya Gupta; Archisman Mahapatra; Anjali Suman; Rahul Kumar Singh
Persistent organic pollutants (POPs) are environmental contaminants that pose significant health risks due to their widespread distribution. This study examines the effects of POPs on male reproductive health using realistic human exposure scenarios. Male mice exposed to 28 ng of POPs for 35 days exhibited detrimental effects on sperm motility and count, significant changes in germ cell composition, and compromised steroidogenesis. Histopathological analyses revealed testicular architecture alterations and abnormal lipid accumulation in the interstitial space, potentially hindering steroidogenesis and Leydig cell function. Western blot and immunofluorescence studies showed reduced levels of steroidogenic markers. Flow cytometry indicated a decrease in round spermatids, suggesting impaired spermatogenesis. Molecular investigations revealed reduced mRNA expression of critical steroidogenic enzymes, while increased apoptotic markers and DNA fragmentation suggested apoptosis as a mechanism. This study highlights the need for stricter regulations and improved environmental health policies to mitigate the adverse effects of POPs on male reproductive health. © 2025 Elsevier B.V.
In silico and in vivo assessment of developmental toxicity, oxidative stress response & Na+/K+-ATPase activity in zebrafish embryos exposed to cypermethrin
(Academic Press, 2023) Priya Gupta; Archisman Mahapatra; Anjali Suman; Rahul Kumar Singh
Cypermethrin (CYP), a synthetic type II pyrethroid pesticide, is extensively used to control pests in industrial, domestic, and agricultural environments. However, its indiscriminate use leads to a potential threat to aquatic organisms. Although several reports focussed on developmental toxicity effects, a concise study combining cardiotoxicity along with Na+/K+-ATPase activity and molecular docking of developmental proteins with CYP was lacking. This present study was designed to address this gap to comprehend the impact of CYP exposure (0, 25, 100 and 200 µg/L) on embryonic zebrafish. As a result, CYP delayed the hatching rate, reduced heart rate, increased mortality rate and induced numerous morphological abnormalities. Subsequently, CYP induced oxidative stress in treated zebrafish embryos with the concomitant increase in antioxidant enzymes (SOD and CAT) and malondialdehyde production. In addition, an alteration in AChE, NO content and Na+/K+-ATPase activity was observed, suggesting a disruption in cardiac development and ion regulation. Furthermore, AO staining showed notable apoptotic cells which are supported by alteration in apoptosis-related gene expressions. Moreover, to explore the putative targets of CYP, computational docking with developmental proteins (WNT3A, WNT8A, GATA-4, Nkx 2–5 and ZHE1) showed strong interactions and binding. Taken together, our findings provide a better understanding of assessing the ecotoxicological risk information and the mode of action underlying the development of teleost fishes following CYP exposure. Meanwhile, the pioneering nature of this study is to emphasize the future use of Na+/K+-ATPase activity as a potential toxicity biomarker and in silico molecular docking studies to complement developmental toxicity findings. © 2023
Ligand-based designing of DPP-4 inhibitors via hybridization; synthesis, docking, and biological evaluation of pyridazine-acetohydrazides
(Institute for Ionics, 2023) Manisha Nidhar; Vipin Kumar; Archisman Mahapatra; Priya Gupta; Brijesh Kumar Yadav; Rahul Kumar Singh; Ashish Kumar Tewari
Abstract: A series of novel pyridazine-acetohydrazide hybrids were designed, synthesized, and evaluated for their in vitro and in vivo antihyperglycemic activity. In this context, pyridazine-acetohydrazides (6a–6p) were synthesized by coupling substituted aldehyde with 2-(5-cyano-6-oxo-3,4-diphenylpyridazine-1-6H-yl) acetohydrazide, which was prepared via the reaction of pyridazine ester with hydrazine hydrate. The molecular docking study was carried out to examine the binding affinities and interaction of designed compounds against the DPP-4 enzyme. Compounds 6e, 6f, 6l, and 6n exhibited interaction with active residue. In silico ADMET properties, and toxicity studies corroborated that compounds were found to have good bioavailability and less toxic. The synthesized compounds were further estimated for in vitro DPP-4 activity. Compounds 6e and 6l were found as the most effective DPP-4 inhibitor in this series with IC50 values (6.48, 8.22 nM) when compared with sitagliptin (13.02 nM). According to the toxicity assay compound, 6l showed very less toxicity at a higher concentration so further selected for the in vivo antihyperglycemic activity. Graphical abstract: [Figure not available: see fulltext.]. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
PFOS-induced dyslipidemia and impaired cholinergic neurotransmission in developing zebrafish: Insight into its mechanisms
(Elsevier Inc., 2023) Archisman Mahapatra; Priya Gupta; Anjali Suman; Shubhendu Shekhar Ray; Rahul Kumar Singh
Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant that has been widely detected in the environment and is known to accumulate in organisms, including humans. The study investigated dose-dependent mortality, hatching rates, malformations, lipid accumulation, lipid metabolism alterations, and impacts on cholinergic neurotransmission. Increasing PFOS concentration led to higher mortality, hindered hatching, and caused concentration-dependent malformations, indicating severe abnormalities in developing zebrafish. The results also demonstrated that PFOS exposure led to a significant increase in total lipids, triglycerides, total cholesterol, and LDL in a concentration-dependent manner, while HDL cholesterol levels were significantly decreased. Additionally, PFOS exposure led to a significant decrease in glucose levels. The study identified TGs, TCHO, and glucose as the most sensitive biomarkers in assessing lipid metabolism alterations. The study also revealed altered expression of genes involved in lipid metabolism, including upregulation of fasn, acaca, and hmgcr and downregulation of ldlr, pparα, and abca1, as well as decreased lipoprotein lipase (LPL) and increased fatty acid synthase (FAS) activity,suggesting an impact on fatty acid synthesis, cholesterol uptake, and lipid transport. Additionally, PFOS exposure led to impaired cholinergic neurotransmission, evidenced by a concentration-dependent inhibition of acetylcholinesterase activity, altered gene expressions related to neural development and function, and reduced Na+/K+-ATPase activity. STRING network analysis highlighted two distinct gene clusters related to lipid metabolism and cholinergic neurotransmission, with potential interactions through the pparα-creb1 pathway. Overall, this study provide important insights into the potential health risks associated with PFOS exposure, including dyslipidemia, cardiovascular disease, impaired glucose metabolism, and neurotoxicity. Further research is needed to fully elucidate the underlying mechanisms and potential long-term effects of PFOS exposure. © 2023 Elsevier Inc.
Polystyrene microplastics disrupt female reproductive health and fertility via sirt1 modulation in zebrafish (Danio rerio)
(Elsevier B.V., 2023) Priya Gupta; Archisman Mahapatra; Anjali Suman; Shubhendu Shekhar Ray; Guilherme Malafaia; Rahul Kumar Singh
Microplastics (MPs) pollution poses an emerging threat to aquatic biota, which could hinder their physiological processes. Recently various evidence has demonstrated the toxic impacts of MPs on cellular and organismal levels, but still, the underlying molecular mechanism behind their toxicity remains ambiguous. The hypothalamic-pituitary-gonadal (HPG) axis regulates the synthesis and release of sex steroid hormones, and SIRT1 plays a vital role in this process. The current study aimed to elucidate the harmful effects of MPs on female reproduction via SIRT1 modulation. Healthy female zebrafish were exposed to different concentrations (50 and 500 µg/L) of polystyrene microplastics (PS-MPs). The results revealed a significant change in the gonadosomatic index (GSI) after exposure to PS-MPs. In addition, the decreased fecundity rate displayed an evident dosage effect, indicating that exposure to PS-MPs causes deleterious effects on fertilization. Furthermore, significantly enhanced levels of reactive oxygen species (ROS) and apoptotic signals through the TUNEL assay were evaluated in different treated groups. Moreover, morphological alterations in the gonads of zebrafish exposed to MPs were also observed through H&E staining. The subsequent change in plasma steroid hormone levels (E2/T ratio) showed an imbalance in hormonal homeostasis. Meanwhile, to follow PS-MPs’ effects on the HPG axis via SIRT1 modulation and gene expression related to steroidogenesis, SIRT1/p53 pathway was evaluated through qPCR. The altered transcription levels of genes indicated the plausible interference of PS-MPs on the HPG axis function. Our in-silico molecular docking study proves that PS-MPs efficiently bind and inhibit endocrine receptors and SIRT1. Thus, these findings add to our understanding of the probable molecular mechanisms of reproductive impairment caused by PS-MPs in zebrafish. © 2023 Elsevier B.V.
Polystyrene microplastics induced disturbances in neuronal arborization and dendritic spine density in mice prefrontal cortex
(Elsevier Ltd, 2024) Anjali Suman; Archisman Mahapatra; Priya Gupta; Shubhendu Shekhar Ray; Rahul Kumar Singh
An increasing use of plastics in daily life leads to the accumulation of microplastics (MPs) in the environment, posing a serious threat to the ecosystem, including humans. It has been reported that MPs cause neurotoxicity, but the deleterious effect of polystyrene (PS) MPs on neuronal cytoarchitectural morphology in the prefrontal cortex (PFC) region of mice brain remains to be established. In the present study, Swiss albino male mice were orally exposed to 0.1, 1, and 10 ppm PS-MPs for 28 days. After exposure, we found a significant accumulation of PS-MPs with a decreased number of Nissl bodies in the PFC region of the entire treated group compared to the control. Morphometric analysis in the PFC neurons using Golgi-Cox staining accompanied by Sholl analysis showed a significant reduction in basal dendritic length, dendritic intersections, nodes, and number of intersections at seventh branch order in PFC neurons of 1 ppm treated PS-MPs. In neurons of 0.1 ppm treated mice, we found only decrease in the number of intersections at the seventh branch order. While 10 ppm treated neurons decreased in basal dendritic length, dendritic intersections, followed by the number of intersections at the third and seventh branch order were observed. As well, spine density on the apical secondary branches along with mRNA level of BDNF was significantly reduced in all the PS-MPs treated PFC neurons, mainly at 1 ppm versus control. These results suggest that PS-MPs exposure affects overall basal neuronal arborization, with the highest levels at 1 and 10 ppm, followed by 0.1 ppm treated neurons, which may be related to the down-regulation of BDNF expression in PFC. © 2024 Elsevier Ltd
Polystyrene microplastics modulated bdnf expression triggering neurotoxicity via apoptotic pathway in zebrafish embryos
(Elsevier Inc., 2023) Anjali Suman; Archisman Mahapatra; Priya Gupta; Shubhendu Shekhar Ray; Rahul Kumar Singh
A ubiquitous presence of microplastics and nanoplastics created a new toxicological research area arising concept of “plastic rivers”. But, the precise molecular mechanisms by which its exposure affects developmental neurotoxicity are poorly understood. Hence, in the present investigation, healthy zebrafish embryos were exposed to different concentrations of 500 nm polystyrene microplastics (0.1 ppm, 1 ppm and 10 ppm) to assess the neurotoxicity and the underlying biomolecular mechanism. On the last day of exposure, behaviour, accumulation, embryotoxicity, acridine orange staining, antioxidant enzyme assay, acetylcholinesterase assay, nitric oxide (NO) estimation, along with neurotransmitter (serotonin, dopamine) quantification and gene expression using qRT-PCR (bdnf, p53, bcl-2, caspase-3, caspase-9) were performed. As a result, we found that zebrafish embryos ingest and bioaccumulate microplastic without causing any morphological changes and lethality. The survival and hatching rates of the embryos were also unaffected but the swimming behaviour patterns were found to be altered. Further, acridine orange staining exhibited more apoptosis in treated groups with increased p53, caspase-3, caspase-9 and decreased bcl-2 gene expression. Moreover, polystyrene microplastics exposure resulted in reduced acetylcholinesterase activity leading to elevated NO concentration along with altered serotonin and dopamine levels and subsequently leading to down-regulated bdnf gene expression and modulated downstream apoptotic signalling, confirming the neurotoxicity potential of microplastics causing neuronal dysfunction. This study also compared the binding affinities between styrene and human proteins (Bdnf, p53 and Bcl-2) using bioinformatics methods, and docking results showed negative binding energy resulting in high binding affinities of Bcl-2 then p53 and Bdnf with styrene. © 2023 Elsevier Inc.
Socio-economic profile of beneficiaries of Swarna Jayanti Gram Swarozgar Yojana (SGSY) of Amaniganj block of Faizabad district (U. P.)
(Agri Bio Research Publishers, 2016) Rahul Kumar Singh; R.K. Doharey; Abhishek Pratap Singh; N.K. Tiwari; Chandan Kumar Singh; Vikas Kumar Singh
A study was conducted in Amaniganj block of Faizabad district of Uttar Pradesh to know the socio-economic profile of beneficiaries of Swarna Jayanti Gram Swarozgar Yojana (SGSY) during the year 2013. One hundred farmers were selected randomly from the list of five purposely selected villages i. e. Raipatti, Manjhanpur Manudeeh, Satemau and Taldholi. The relevant variables were selected after reviewing the literatures available and the works done in the field prior to the present investigation. Age, caste, family size, family type, land holding capacity, occupation, social participation, material possession, scientific orientation, economic motivation, risk orientation and value orientation were considered as socio-economic indicators. A well structured and pre-tested interview schedule was used for data collection through personal interview method. The data were analyzed by using percentage, mean and standard deviation. The findings of the study revealed that majority of the respondents were middle aged (66%), literate (82 %) and belonged to general caste (40%). Majority of the respondents belonged to nuclear family (52%), medium sized family (69%) with mixed housing pattern (56%) and having marginal land holding (72%); most of them adopted agriculture as a main occupation (15.00%) and participated in one organization (41%). Majority of the respondents (70%) were observed to be in the medium category (17-53 scores) of materials possession and having medium level of economic motivation (67%); majority of the respondents were having medium level of scientific orientation (66%), medium level of risk orientation (62%) and had medium level of value orientation (59%).
Sorption of PFOS onto polystyrene microplastics potentiates synergistic toxic effects during zebrafish embryogenesis and neurodevelopment
(Elsevier Ltd, 2024) Priya Gupta; Archisman Mahapatra; Bharat Manna; Anjali Suman; Shubhendu Shekhar Ray; Naresh Singhal; Rahul Kumar Singh
Microplastics (MPs) have become an emerging anthropogenic pollutant, and their ability to sorb contaminants potentially enhances the threats to the ecosystem. Only a few studies are available to understand the combined effects of microplastics and other pollutants. The present study investigated the sorption of perfluorooctane sulfonic acid (PFOS) onto polystyrene microplastics (PS-MPs) at varying concentrations, using molecular dynamics simulation (MDS) to preliminarily explore the adsorption behavior. The MDS results revealed negative interaction energies between PFOS and PS-MPs, underscoring PS-MPs' role as a potential adsorbent for PFOS in an aqueous solution. Thereafter, zebrafish embryos were employed to explore the toxic effects of combined exposure to PS-MPs and PFOS. Fluorescence and Scanning Electron Microscopy (SEM) suggested PS-MP accumulation individually and in combination with PFOS on the embryonic chorion membrane. As a result, the exposed group showed increased inner pore size of the chorionic membrane and accelerated heartbeat, indicating hypoxic conditions and hindered gaseous exchange. PS-MPs aggravated the toxicity of PFOS during larval development manifested by delayed hatching rate, increased mortality, and malformation rate. Additionally, increased ROS accumulation and altered antioxidant enzymatic status were observed in all the exposed groups suggesting perturbation of the redox state. Additionally, co-exposure of zebrafish larvae to PS-MPs and PFOS resulted in an abrupt behavioral response, which decreased AChE activity and altered neurotransmitter levels. Taken together, our results emphasize that PS-MPs can act as a potential vector for PFOS, exerting synergistic toxic effects in the aquatic environment, and hence their health risks cannot be ignored. © 2024 Elsevier Ltd
Unraveling the mechanisms of perfluorooctanesulfonic acid-induced dopaminergic neurotoxicity and microglial activation in developing zebrafish
(Elsevier B.V., 2023) Archisman Mahapatra; Priya Gupta; Anjali Suman; Shubhendu Shekhar Ray; Guilherme Malafaia; Rahul Kumar Singh
Perfluorooctanesulfonic acid (PFOS) is a prevalent, persistent organic pollutant in environmental matrices, yet its precise mechanism of neurotoxicity remains unclear. This study investigated the developmental and neurobehavioral effects of PFOS exposure (0, 100, 500, and 1000 μg/L) on zebrafish. The findings indicated that PFOS exposure caused various developmental abnormalities, including increased mortality, delayed hatching, shortened body length, bent spine, and edema in the pericardial and yolk sac regions. Subsequently, larvae exhibited a significant decrease in spontaneous movement frequency, altered touch-evoked response, and locomotor behavior. In fact, aberrant cellular responses in the brain and cardiac regions were observed. Microglial activation is a critical component of the inflammatory immune responses related to neurotoxicity. Likewise, our findings indicated that PFOS-induced microglial activation might be responsible for neuronal inflammation and apoptosis. Furthermore, AChE activity and dopamine content at the neurotransmitter level were also disrupted after PFOS exposure. The gene expression of dopamine signaling pathways and neuroinflammation were also altered. Collectively, our findings highlight that PFOS exposure can induce dopaminergic neurotoxicity and neuroinflammation through microglial activation, thus ultimately affecting behavior. Taken together, this study will provide mechanistic effects underlying the pathophysiology of neurological disorders. © 2023 Elsevier B.V.