Browsing by Author "Atul Srivastava"

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Antioxidant and antibacterial property of biosynthesised silver nanoparticles
(Tehran University of Medical Sciences, 2021) Anand Kumar Keshari; Atul Srivastava; Sandip Chowdhury; Ragini Srivastava
Objective(s): The present work shows the green synthesis of silver nanoparticles using C. roseus extract and its antioxidant, free radicals scavenging and antibacterial activities. Methods: The C. roseus extract synthesized silver nanoparticles (CrAgNPs) were characterized by X-ray diffractometry, Scanning Electron Microscopy, Transmission Electron Microscopy and Fourier Transform Infra Red spectroscopy. The antioxidant, hydrogen peroxide scavenging, hydroxyl radicals scavenging, superoxide scavenging and reducing power activity of CrAgNPs were determined by DPPH, hydrogen peroxide scavenging, hydroxyl radicals scavenging, superoxide scavenging and reducing power assay methods. The antibacterial activity of CrAgNPs was analyzed by Agar dilution, Minimum Inhibitory Concentration methods. Results: The CrAgNPs were synthesized by C. roseus extract and silvernitrate. The synthesis of silver nanoparticles was confirmed by color changes and UV-visible spectrophotometer analysis. The CrAgNPs were crystalline, variable size, elemental and spherical shape. The C. roseus extract and CrAgNPs have antioxidant, hydrogen peroxide scavenging, hydroxyl radicals scavenging, superoxide scavenging and reducing power activity. The zone of inhibition and MIC value of CrAgNPs confirmed the antibacterial activity. The CrAgNPs have greater antibacterial activity than C. roseus extract against the S. Typhi and P. vulgaris. The MIC results of CrAgNPs confirmed that CrAgNPs was highly effective against the S. Typhi and P. vulgaris bacteria. Conclusions: Phenols and flavonoids of C. roseus extract reduced the silvernitrate into silver nanoparticles. The CrAgNPs were crystalline, spherical shape, variable particles size and elemental. The C. roseus extract and CrAgNPs have antioxidant, hydrogen peroxide scavenging, hydroxyl radicals scavenging, superoxide scavenging, reducing power activity and antibacterial activity. © 2021 Nanomedicine Research Journal.
Basic overview of human physiology
(Elsevier, 2020) Atul Srivastava; Mrinalini Kumari; Dinesh Prasad Gond; Subhashini
Physiology has been defined as the branch of science dedicated to analyze and understand all the events, activities and functions of the living system. It is the study of normal function and vital processes of living organism. Classified as the sub-section and subdivision of biology and zoology, it covers a range of subject that include organs, anatomy, cells, biological compounds, and how they all interact to make life possible. The different division of physiology are only the various attempts to approach and understand the same problem from different angle. System biology considers all living phenomena as emergent properties due to interface among components of the system. Each system is highly complicated and each functions properly only when it cooperates with the other in maintaining the proper internal environment. The present knowledge of physiology has already assumed gigantic proportion and recent researches are adding everyday something new to it. The present review gives an idea about the major human physiological process like movement, digestion, respiration, blood circulation their composition and functioning and how each system are interrealated affecting functioning of other regulating the body function. © 2020 Elsevier Inc. All rights reserved.
Blocking μ-opioid receptor by naltrexone exaggerates oxidative stress and airway inflammation via the MAPkinase pathway in a murine model of asthma
(Elsevier Inc., 2024) Vinita Pandey; Vandana Yadav; Atul Srivastava; Pratikkumar Gaglani; Rashmi Singh; Subhashini
Opioids regulate various physiological and pathophysiological functions, including cell proliferation, immune function, obesity, and neurodegenerative disorders. They have been used for centuries as a treatment for severe pain, binding to opioid receptors a specific G protein-coupled receptor. Common opioids, like β-endorphin, [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO), and dynorphins, have analgesic effects. The use of a potent antagonist, like naltrexone hydrochloride, to block the effects of mu Opioid Receptor (μOR) may result in the withdrawal of physiological effects and could potentially impact immune responses in many diseases including respiratory disease. Asthma is a respiratory disease characterized by airway hyperresponsiveness, inflammation, bronchoconstriction, chest tightness, stress generation and release of various cytokines. Airway inflammation leads recruitment and activation of immune cells releasing mediators, including opioids, which may modulate inflammatory response by binding to their respective receptors. The study aims to explore the role of μOR antagonist (naltrexone) in regulating asthma pathophysiology, as the regulation of immune and inflammatory responses in asthma remains unclear. Balb/c mice were sensitized intranasally by 1% TDI and challenged with 2.5% TDI. Naltrexone hydrochloride (1 mg/kg body weight) was administered through intraperitoneal route 1 h before TDI induction. Blocking μOR by naltrexone exacerbates airway inflammation by recruiting inflammatory cells (lymphocytes and neutrophils), enhancing intracellular Reactive oxygen species in bronchoalveolar lavage fluid (BALF), and inflammatory mediator (histamine, Eosinophil peroxidase and neutrophil elastase) in lungs. Naltrexone administration modulated inflammatory cytokines (TNF-α, IL-4, IL-5, IL-6, IL-10, and IL-17A), and enhanced IgE and CRP levels. Naltrexone administration also increased the expression of NF-κB, and phosphorylated p-P38, p-Erk, p-JNK and NF-κB by inhibiting the μOR. Docking study revealed good binding affinity of naltrexone with μOR compared to δ and κ receptors. In future it might elucidate potential therapeutic against many respiratory pathological disorders. In conclusion, μOR blocking by naltrexone regulates and implicates inflammation, bronchoconstriction, and lung physiology. © 2023 Elsevier Inc.
Comparative evaluation of salivary, serum, and GCF alkaline phosphatase levels in chronic periodontitis patients before and after nonsurgical periodontal therapy: A clinico-biochemical study
(Wolters Kluwer Medknow Publications, 2024) Sarita Parihar; Preeti Singh; Ragini Srivastava; Atul Srivastava; Fouzia Imran; J.P. Vishnu
Background: Chronic periodontitis is a multifactorial disease that causes the supporting tissues around the teeth to become inflamed and destroyed, which further causes tooth mobility and eventual tooth loss. The enzyme alkaline phosphatase (ALP), which is involved in bone resorption and gingival inflammation, is an important biomarker. The current study's objective is to compare the serum, gingival crevicular fluid (GCF), and salivary levels of ALP in individuals with chronic periodontitis before and after nonsurgical periodontal therapy. Materials and Methods: On the basis of clinical and radiographic examinations, 72 participants were split into two groups: Group I (healthy individuals) and Group II (chronic periodontitis patients). All patients who were in an aseptic condition had their serum, GCF, and unstimulated saliva taken, and samples were then tested for ALP levels using ALP kit. Results: The difference in salivary, serum, and GCF ALP levels between the control group (23.44 ± 4.76, 58.88 ± 8.29, and 776.76 ± 121.91) and the study group (105.66 ± 16.33, 102.38 ± 4.43, and 1,825.77 ± 275.12) was found to be statistically significant with P < 0.001. The difference in salivary, serum, and GCF ALP levels from baseline (105.66 ± 16.33, 102.38 ± 4.43, and 1,825.77 ± 275.12) to postoperative (49.54 ± 5.69, 83.46 ± 4.22, and 1,148.38 ± 129.01) was found to be statistically significant with P < 0.001. The results demonstrated that patients with chronic periodontitis have considerably higher levels of serum, GCF, and salivary ALP than healthy individuals. Conclusion: Salivary and GCF ALP can thus be used as a key inflammatory diagnostic biomarker in periodontal diseases. © 2024 National Journal of Maxillofacial Surgery.
Current and future prospects of nanoparticles to combat bacterial infections
(Elsevier, 2022) Dinesh Prasad Gond; Atul Srivastava; Subhashini; Anjney Sharma; Kumari Mrinalini
Bacterial infections are a major public health problem that result high morbidity and mortality. There are several options for antibacterial therapy, however, their efficacies are limited, particularly due to the developing resistance mechanism. In the past decade, a great advance in nanomedicine has shown promise for the treatment of bacterial infection. In the current perspective for medicine application or medical therapies, nanotechnology using nanoscale materials is increasingly being utilized for clinical applications, especially as a new paradigm to combat bacterial infections. The nanoparticles can act as antibacterial agents or carriers for loading antibacterial drugs to promote the bioavailability and effectiveness of antibiotics. Nanoparticles may penetrate the cell membrane of pathogenic microorganisms and interfere with important molecular pathways, formulating unique antimicrobial mechanisms. These particles have also demonstrated synergy in combination with optimal antibiotics and may aid in limiting the global crisis of emerging bacterial resistance. In the current chapter, we have highlighted and summarized the potentially significant impact of nanoparticles as antibacterial agents, the recent progress on the development of antibacterial nanoparticles, and the subsequent approaches and challenges for clinical applications. This chapter offers an overview of the current and future prospects of antibacterial nanosystems. © 2023 Elsevier Inc. All rights reserved.
Highly enhanced fluorescence parameters in a dye-doped liquid crystalline compound
(Taylor and Francis Ltd., 2024) Shivangi Tripathi; Shikha Agarwal; Sadhna Tiwari; Dhananjay Kumar Gaur; Atul Srivastava; Rajiv Manohar
Fluorescent liquid crystalline compounds have been the focal point of research due to their rich applications in organic optoelectronics. Fluorescent dyes have also found great applications in the development of random lasers and non-linear optics. Other than that, materials with high fluorescence intensity and quantum yield have been very desirable for various electro-optical applications over the years. We have attempted to engineer a highly fluorescent nematic liquid crystalline compound (4′-pentyl-4-biphenylcarbonitrile/5CB) with high quantum yield by doping anthracene dye. We have obtained the desired increase in fluorescence intensity due to anthracene being fluorescent as well and a further significantly high quantum yield for higher concentrations of anthracene in the nematic compound. The reduction in non-emissive radiations and the increase in the concentration of fluorophores in the excited state can be held responsible for this increased quantum yield. Lifetime of the fluorophores has been found to increase with the increase in the dye concentration. The obtained results make the anthracene-doped 5CB compound highly desirable for various device applications. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
Inhibiting SIRT-2 by AK-7 restrains airway inflammation and oxidative damage promoting lung resurgence through NF-kB and MAP kinase signaling pathway
(Frontiers Media SA, 2024) Vandana Yadav; Vinita Pandey; Pratikkumar Gaglani; Atul Srivastava; Soni; Subhashini
Introduction: Chronic obstructive pulmonary disease (COPD) is a major global cause of mortality with limited effective treatments. Sirtuins (SIRT) are histone deacetylases that are involved in the regulation of redox and inflammatory homeostasis. Hence, the present study aims to investigate the role of SIRT-2 in modulating inflammation in a murine model of COPD. Methods: COPD in mice was established by cigarette smoke (CS) exposure for 60 days, and AK-7 was used as the specific SIRT-2 inhibitor. AK-7 (100 µg/kg and 200 µg/kg body weight) was administered intranasally 1 h before CS exposure. Molecular docking was performed to analyze the binding affinity of different inflammatory proteins with AK-7. Results: Immune cell analysis showed a significantly increased number of macrophages (F4/80), neutrophils (Gr-1), and lymphocytes (CD4+, CD8+, and CD19+) in the COPD, group and their population was declined by AK-7 administration. Total reactive oxygen species, total inducible nitric oxide synthase, inflammatory mediators such as neutrophil elastase, C-reactive protein, histamine, and cytokines as IL4, IL-6, IL-17, and TNF-α were elevated in COPD and declined in the AK-7 group. However, IL-10 showed reverse results representing anti-inflammatory potency. AK-7 administration by inhibiting SIRT-2 decreased the expression of p-NF-κB, p-P38, p-Erk, and p-JNK and increased the expression of Nrf-2. Furthermore, AK-7 also declined the lung injury by inhibiting inflammation, parenchymal destruction, emphysema, collagen, club cells, and Kohn pores. AK-7 also showed good binding affinity with inflammatory proteins. Discussion: The current study reveals that SIRT-2 inhibition mitigates COPD severity and enhances pulmonary therapeutic interventions, suggesting AK-7 as a potential therapeutic molecule for COPD medication development. Copyright © 2024 Yadav, Pandey, Gaglani, Srivastava, Soni and Subhashini.
Microbial biofilms and their role in acute and chronic pathogenesis
(Elsevier, 2024) Atul Srivastava; Mrinalini Kumari; Dinesh Prasad Gond; Subhashini
The context of microorganism living within the commune rather than merely as autonomous individual is one of the quickly gaining acceptances. These communities of the organism residing within the extracellular polymeric substance matrix are termed biofilms. A biofilm is an assembly of microbial cells that is irretrievably linked with a surface and covered primarily in a matrix of polysaccharide material. The ability to figure biofilms is a universal attribute of all microorganisms including bacteria. Biofilms may impact human health both positively and negatively. With the tendency to grow anywhere on abiotic as well as biotic surfaces, these act as a potent source of various infections. The rising burden of several diseases caused by microbial infections implies an immense menace to global health. Biofilm formation has been confirmed in numerous pathogens and is evidently mentioned as an important strategy for microbial survival. This chapter provides an overview on biofilms, their structure and formation, and their impact on human health. The current chapter also entails light on the involvement of biofilms in pulmonary infections and existing strategies employed for the treatment. © 2024 Elsevier Inc. All rights reserved.
Nutrient chemistry and eutrophication risk assessment of the Ghaghara river, India
(IWA Publishing, 2021) Nirdesh Kumar Ravi; Atul Srivastava; Pawan Kumar Jha; Kirpa Ram
This study was carried out to evaluate the eutrophication risk associated with the nutrient flux from the Ghaghara river by using nutrient molar ratios and indicators for coastal eutrophication potential values. The concentration of ammonium (3-8 times), nitrate (3-10 times), and phosphate (3-4.5 times) in the Ghaghara river were higher than the reported value for the unpolluted rivers, indicating the contribution from the anthropogenic sources. The dissolved nutrients concentration showed significant seasonal variations in the Ghaghara river system. The specific yield of nitrate-N, phosphate-P, and dissolved silica-Si from the Ghaghara river were 0.49,0.03 and 0.96 tons kmr2 yr~1 respectively. The average molar ratio for dissolved inorganic nitrogen (DIN)/Dissolved inorganic Phosphate (DIP) was above 16:1, which indicated phosphate limitation in biological productivity. In contrast, an average molar ratio of Dissolved inorganic Silica (DSi)/DIN of 4.6 ± 4.4 favored the diatom growth in the Ghaghara river. The negative value of P-ICEP (-2.93 kg C. kmr2day~1) indicated phosphate limitation in the Ghaghara river. The positive value of N-ICEP (1.71 kg Ckmr2day~1) indicates an excess of nitrogen over silica transport from the Ghaghara river to the Ganga river, which can create an eutrophication problem in the Ganga river. © 2021 The Authors
Pharmacological inhibition of SIRT-2 by AK-7 modulates redox status and apoptosis via regulating Nrf2 in an experimental model of chronic obstructive pulmonary disease: an invivo and insilico study
(Taylor and Francis Ltd., 2023) Vandana Yadav; Vinita Pandey; Atul Srivastava; Sangita Singh; Subhashini
Chronic obstructive pulmonary disease (COPD) is defined by inflammation and emphysema. Sirtuins (SIRT) are NAD+-dependent histone deacetylases that regulate oxidative stress and inflammation. The present work investigates the modulatory role of SIRT-2 in experimental COPD model. Insilico comparative assessment of SIRT-2 inhibitors (AK-7 and AGK-2) by ADMET and molecular docking revealed AK-7 as suitable candidate for invivo application. COPD in mice was established by cigarette smoke (CS) exposure for 2 months. AK-7 (100 µg/kg and 200 µg/kg body weight) was administered intranasally one hour before CS exposure. The present investigation demonstrates that CS exposure increases total cell count, and free radical production (total reactive oxygen species, total oxidant status, myeloperoxidase, and nitric oxide), which were decreased by AK-7. It also altered antioxidant enzymatic activity (total antioxidant status, catalase, superoxide dismutase, glutathione peroxidase, glutathione-s-transferase, glutathione reductase, and reduced glutathione), hence preserving the redox balance. AK-7 significantly decreases apoptosis, protein carbonylation, lipid peroxidation, TNF-α and IFN-ﻻ levels represent COPD generation in mice and were dramatically decreased by AK-7. Histopathological studies shows that CS exposure damages alveoli and produces peribronchiolar inflammation; both of these events were reduced by AK-7. The antioxidative potency of AK-7 was confirmed by observing Nrf2 and Keap1 proteins. Keap-dependent Nrf2 regulation was observed, with cytosolic Nrf2 and Keap1 expression elevated in COPD and reduced in the AK-7 group while nuclear Nrf2 was reduced in COPD and increased in the AK-7 group. The present study concludes that inhibition of SIRT-2 minimizes COPD severity and mediates therapeutic effects in the lungs. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
Potential of hydroethanolic leaf extract of Ocimum sanctum in ameliorating redox status and lung injury in COPD: an in vivo and in silico study
(Nature Research, 2023) Atul Srivastava; Subhashini; Vinita Pandey; Vandana Yadav; Sangita Singh; Ragini Srivastava
Oxidative stress and inflammation are hypothesised as the main contributor for Chronic Obstructive Pulmonary Disease (COPD). Cigarette smoke (CS), a major cause of COPD leads to inflammation resulting in recruitment of neutrophils and macrophages which are rich sources of oxidants. Activation of these cells produces excess oxidants and depletes antioxidants resulting in stress. Presently, effective drug for COPD is limited; therefore, novel compounds from natural sources, including plants are under exploration. The present study aims to investigate the protective effect of Ocimum sanctum leaf extract (OLE) in CS − induced model of COPD. Exposure to CS was performed thrice a week for 8 weeks and OLE (200 mg/kg and 400 mg/kg) was administered an hour before CS exposure. Control group (negative control) were exposed to ambient air while COPD group was exposed to CS (positive control). Administration of OLE doses reduced inflammation, decreased oxidant concentration and increased antioxidant concentration (p < 0.01). Molecular docking studies between the major phytocompounds of OLE (Eugenol, Cyclohexane and Caryophyllene) and antioxidant enzymes Superoxide dismutase (SOD), Catalase, Glutathione peroxidase (GPx), Glutathione reductase (GR) and Glutathione S Transferase (GST) showed strong binding interaction in terms of binding energy. In vivo and in silico findings for the first time indicates that OLE extract significantly alleviates oxidative stress by its potent free radical scavenging property and strong interaction with antioxidant enzymes. OLE extract may prove to be a therapeutic option for COPD prevention and treatment. © 2023, The Author(s).
Recent applications of nanomedicine in lung disease
(Elsevier, 2022) Atul Srivastava; Mrinalini Kumari; Dinesh Prasad Gond; Subhashini
Lung diseases include a wide spectrum of illnesses, such as asthma, COPD (chronic obstructive pulmonary disease), pneumonia, tuberculosis, lung cancers, and the recent COVID-19 pandemic, and have been a huge threat to human health and life. However, the treatment and diagnosis of various lung diseases are challenging. Among the several treatment strategies and diagnostic techniques, the adverse effect to chemotherapy in cancers, multidrug resistance in tuberculosis, side effects, toxicity, poor drug delivery, and metabolism require the development of novel and promising alternative treatments. Nanotechnology provides a promising tool for the development of innovative treatment overcoming many drug challenges. Nanotechnology being widely studied in medicinal field has given rise to the interdisciplinary nanomedicine field allowing fundamental changes in the diagnosis, treatment, and prevention of disease. Lungs provide a good target organ for drug delivery via an aerosol inhalation mode. Lungs provide a large surface area for local drug action and systemic drug absorption and hence nanomedicines have been a boon in treating many of the lung diseases without leading to any side effects or toxicity. The present chapter aims to review nanoparticles-based drug delivery systems studied over the last decade as therapeutic agents in lung diseases. © 2023 Elsevier Inc. All rights reserved.
Screening of essential oils of angiospermic plants for their fungitoxicity against Aspergillus Flavus and Aspergillus Niger
(International Journal of Pharma and Bio Sciences, 2015) Atul Srivastava; Pradeep Kumar Shukla; Ashwini Kumar Mishra; Subhashini; Suchit John
Essential oils obtained from plants have recently gained a great scientific interest as a potent source of antimicrobials of natural origin. The present study highlights the antifungal activity of essential oils against Aspergillus flavus and Aspergillus niger. During screening of essential oils of six selected Angiospermic plants at 2000 ppm (mg/l) against the test fungus, Mentha arvensis and Citrus aurantifolia, being most effective was selected for further study. The selected oils were subsequently standardized through physicochemical and fungitoxic properties. The MIC values of Mentha arvensis and Citrus aurantifolia were found to be 1000 and 2000 ppm (mg/l) respectively. Fungitoxicity of both oils represents fungicidal, as well as fungistatic behavior at their respective MIC(s). Study also revealed that oil of Mentha arvensis and Citrus aurantifoila are highly thermo stable (up to 80°C) and had the potency to withstand high inoculum density. The fungitoxicity of both the oils remained unaltered up to 180-210 days at room temperature. The antifungal potency of oils was found greater when compared with some prevalent synthetic commercial fungicides. Therefore oils could be recommended as a potential source of ecofriendly herbal fungicide and might have role as pharmaceutical and preservatives.
β-Endorphin (an endogenous opioid) inhibits inflammation, oxidative stress and apoptosis via Nrf-2 in asthmatic murine model
(Nature Research, 2023) Vinita Pandey; Vandana Yadav; Rashmi Singh; Atul Srivastava; Subhashini
Asthma, a chronic respiratory disease is characterized by airway inflammation, remodelling, airflow limitation and hyperresponsiveness. At present, it is considered as an umbrella diagnosis consisting several variable clinical presentations (phenotypes) and distinct pathophysiological mechanisms (endotypes). Recent evidence suggests that oxidative stress participates in airway inflammation and remodelling in chronic asthma. Opioids resembled by group of regulatory peptides have proven to act as an immunomodulator. β-Endorphin a natural and potent endogenous morphine produced in the anterior pituitary gland play role in pain modulation. Therapeutic strategy of many opioids including β-Endorphin as an anti‑inflammatory and antioxidative agent has not been yet explored despite its promising analgesic effects. This is the first study to reveal the role of β-Endorphin in regulating airway inflammation, cellular apoptosis, and oxidative stress via Nrf-2 in an experimental asthmatic model. Asthma was generated in balb/c mice by sensitizing with 1% Toulene Diisocyanate on day 0, 7, 14 and 21 and challenging with 2.5% Toulene Diisocyanate from day 22 to 51 (on every alternate day) through intranasal route. β-Endorphin (5 µg/kg) was administered through the nasal route 1 h prior to sensitization and challenge. The effect of β-Endorphin on pulmonary inflammation and redox status along with parameters of oxidative stress were evaluated. We found that pre-treatment of β-Endorphin significantly reduced inflammatory infiltration in lung tissue and cell counts in bronchoalveolar lavage fluid. Also, pre-treatment of β-Endorphin reduced reactive oxygen species, Myeloperoxidase, Nitric Oxide, Protein and protein carbonylation, Glutathione Reductase, Malondialdehyde, IFN-γ, and TNF-α. Reversely, β-Endorphin significantly increased Superoxide dismutase, Catalase, glutathione, Glutathione-S-Transferase, and activation of NF-E2-related factor 2 (Nrf-2) via Kelch-like ECH-associated protein 1 (Keap1), independent pathway in the lung restoring architectural alveolar and bronchial changes. The present findings reveal the therapeutic potency of β-END in regulating asthma by Keap-1 independent regulation of Nrf-2 activity. The present findings reveal the therapeutic potency of β-Endorphin in regulating asthma. © 2023, The Author(s).