Browsing by Author "Ashish Dwivedi"

Now showing 1 - 14 of 14

Ambient UV-B exposure reduces the binding of ofloxacin with bacterial DNA gyrase and induces DNA damage mediated apoptosis
(Elsevier Ltd, 2016) Jyoti Singh; Ashish Dwivedi; Syed Faiz Mujtaba; Krishna P. Singh; Manish Kumar Pal; Deepti Chopra; Shruti Goyal; Ajeet K. Srivastav; Divya Dubey; Shailendra K. Gupta; Chandana Haldar; Ratan Singh Ray
Ofloxacin (OFLX) is a broad spectrum antibiotic, which generates photo-products under sunlight exposure. Previous studies have failed to explain the attenuated anti-bacterial activity of OFLX. The study was extended to explore the unknown molecular mechanism of photogenotoxicity on human skin cell line (HaCaT) under environmental UV-B irradiation. Photochemically OFLX generates ROS and caused 2′-dGuO photodegradation. We have addressed the binding affinity of OFLX and its photo-products against DNA gyrase. Significant free radical generation such as 1O2, O2•- and •OH reduces antioxidants and demonstrated the ROS mediated OFLX phototoxicity. However, the formation of micronuclei and CPDs showed photogenotoxic potential of OFLX. OFLX induced cell cycle arrest in sub-G1 peak. OFLX triggers apoptosis via permeabilization of mitochondrial membrane with the downregulation of anti-apoptotic Bcl-2 and caspase-3 whereas, upregulation of pro-apoptotic Bax and Cyto-C proteins. Our study illustrated that binding affinity of OFLX photo-products with DNA gyrase was mainly responsible for the attenuated antimicrobial activity. It was proved through molecular docking study. Thus, study suggests that sunlight exposure should avoid by drug users especially during peak hours for their safety from photosensitivity. Clinicians may guide patients regarding the safer use of photosensitive drugs during treatment. © 2016 Published by Elsevier Ltd.
Corrigendum to “PLGA nanoformulation of sparfloxacin enhanced antibacterial activity with photoprotective potential under ambient UV-R exposure” [Int. J. Pharm. 541 (2018) 173–187] (International Journal of Pharmaceutics (2018) 541(1–2) (173–187), (S0378517318301091) (10.1016/j.ijpharm.2018.02.028))
(Elsevier B.V., 2018) Jyoti Singh; Ashish Dwivedi; Lipika Ray; Deepti Chopra; Divya Dubey; Ajeet K. Srivastva; Smita Kumari; Randhir Kumar Yadav; Saroj Kumar Amar; Chandana Haldar; Ratan Singh Ray
The authors regret that mistakes related to image duplication, quality and labeling were found in Fig. 7b Fig. 9 Fig. 10 a. The corrected images are now provided as Figs. 7b, 9c, d and 10a. These mistakes do not change the scientific conclusions of the article in any way. The authors would like to apologise for any inconvenience caused. © 2018 Elsevier B.V.
Corrigendum to “PLGA nanoformulation of sparfloxacin enhanced antibacterial activity with photoprotective potential under ambient UV-R exposure” [Int. J. Pharm. 541 (2018) 173–187](S0378517318301091)(10.1016/j.ijpharm.2018.02.028)
(Elsevier B.V., 2019) Jyoti Singh; Ashish Dwivedi; Lipika Ray; Deepti Chopra; Divya Dubey; Ajeet K. Srivastva; Smita Kumari; Randhir Kumar Yadav; Saroj Kumar Amar; Chandana Haldar; Ratan Singh Ray
The authors regret to inform that there were inadvertent errors in some figures. The corrected images are given below. These corrections are not affecting the results and conclusion of the manuscript. Hence, the text in the original article remains unchanged. The corrected Fig. 8 is as follows: The corrected Fig. 12 is as follows: The authors would like to apologise for any inconvenience caused. © 2019 Elsevier B.V.
MicroRNA: a new and promising potential biomarker for diagnosis and prognosis of ovarian cancer
(Cancer Biology and Medicine, 2015) Manish K. Pal; Shyam P. Jaiswar; Vinaya N. Dwivedi; Amit K. Tripathi; Ashish Dwivedi; Pushplata Sankhwar
Epithelial ovarian cancer (EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biological markers (mRNA and proteins biomarkers), the mortality rate of ovarian cancer remains a challenge because of its late diagnosis, which is specifically attributed to low specificities and sensitivities. Under this compulsive scenario, recent advances in expression biology have shifted in identifying and developing specific and sensitive biomarkers, such as microRNAs (miRNAs) for cancer diagnosis and prognosis. MiRNAs are a novel class of small non-coding RNAs that deregulate gene expression at the posttranscriptional level, either by translational repression or by mRNA degradation. These mechanisms may be involved in a complex cascade of cellular events associated with the pathophysiology of many types of cancer. MiRNAs are easily detectable in tissue and blood samples of cancer patients. Therefore, miRNAs hold good promise as potential biomarkers in ovarian cancer. In this review, we attempted to provide a comprehensive profile of key miRNAs involved in ovarian carcinoma to establish miRNAs as more reliable non-invasive clinical biomarkers for early detection of ovarian cancer compared with protein and DNA biomarkers. Copyright © 2015 by Cancer Biology & Medicine.
Photoaging
(Springer Singapore, 2018) Jyoti Singh; Deepti Chopra; Ashish Dwivedi; Ratan Singh Ray
The incident of photoaging mainly depends upon the intensity of UV-R and the amount of melanin present in the skin. UV-R is known to cause photoaging, photoallergy, and immune suppression to human skin, noted more than a century ago. From last 10 years, several laboratory studies show that UV rays impaired the collagen synthesis, blocked collagen expression, and reduced the elasticity of skin and solar scar formation which is ultimately visible by clinical pattern such atrophy and wrinkle formation. Which further leads to UV-R induced premature aging of the skin. UV radiation alters the ECM by raising the level of matrix metalloproteinases (MMP), decreasing the structural elastin and collagen, directly or indirectly damaging the DNA, and enhancing the cell surface receptors which are present at the surface of keratinocytes and fibroblasts of skin. AP-1 and NF-kB are key signaling molecules which involve in UV-R promoted skin aging. The photoprotective approaches to prevent or treat photocarcinogenesis and photoaging involve natural supplements absorption by orally and topically. Skin accommodates a complex system of endogenous enzymatic and nonenzymatic photoprotective antioxidants. However, their role in the UV-R-induced oxidative damage has not been fully elucidated. Recently, the researchers have elucidated that skin antioxidative defense system is increased in presence of vitamins and nutritive agents and combination of various kinds of antioxidants also produce synergistic results. © Springer Nature Singapore Pte Ltd. 2018.
PLGA nanoformulation of sparfloxacin enhanced antibacterial activity with photoprotective potential under ambient UV-R exposure
(Elsevier B.V., 2018) Jyoti Singh; Ashish Dwivedi; Lipika Ray; Deepti Chopra; Divya Dubey; Ajeet K. Srivastva; Smita Kumari; Randhir Kumar Yadav; Saroj Kumar Amar; Chandana Haldar; Ratan Singh Ray
Sparfloxacin (SPFX) is a broad spectrum antibiotic which inhibits bacterial DNA gyrase enzyme activity. However, photodegradation in the presence of UVA limits its antibacterial activity and induces phototoxicity. Thus, to encounter this problem, we have developed poly d,l-lactic-co-glycolic acid (PLGA) loaded SPFX nanoparticles. Here, we have performed a comparative antibacterial activity of SPFX and its nanoparticles (NPs) through molecular docking and plate sensitivity assay. Under environmental UVA exposure, photoexcited SPFX significantly generates ROS, DNA damage and mitochondrial mediated cell death in comparison to PLGA-SPFX-NPs (nano SPFX) in human skin cell line (HaCaT). In presence of UVA, bulk SPFX induced cell cycle arrest with appearance of sub-G1 peak showing apoptosis while nano SPFX did not show any change. SPFX triggered apoptosis via alteration in membrane integrity of mitochondria and lysosome in comparison to PLGA-SPFX-NPs. Involvement of mitochondrial mediated cell death was confirmed by down-regulation of anti-apoptotic Bcl-2 and procaspase-3 and upregulation of pro-apoptotic Bax, cytochrome-c and caspase-3 proteins expression. Specific caspase inhibitor, Z-VAD-FMK showed involvement of caspase cascade pathway in apoptosis. Our finding suggests that controlled release of SPFX from PLGA-SPFX-NPs can reduce its side effects and enhance its antibacterial activity. Thus, nanotization of fluoroquinolones will be a significant step to reduce the problem of resistance and phototoxicity of this group. © 2018 Elsevier B.V.
Preface
(Springer Singapore, 2020) Ashish Dwivedi; Neeraj Agarwal; Lipika Ray; Amit Kumar Tripathi
[No abstract available]
RETRACTED: Ambient UV-B exposure reduces the binding of ofloxacin with bacterial DNA gyrase and induces DNA damage mediated Apoptosis (International Journal of Biochemistry and Cell Biology (2016) 73 (111–126), (S1357272516300012), (10.10.1016/j.biocel.2016.01.001))
(Elsevier Ltd, 2019) J. Singh; Ashish Dwivedi; Syed Faiz Mujtaba; Krishna P. Singh; Manish Kumar Pal; Deepti Chopra; Shruti Goyal; Ajeet K. Srivastav; D. Dubey; Shailendra K. Gupta; Chandana Haldar; Ratan Singh Ray
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. The study is retracted due to image duplication reasons: The article contains an image that had already appeared in Free Radic Res, 48.3 (2014): 333-346. doi:10.3109/10715762.2013.869324. The images are used in both papers but to conclude something entirely different, and suggested that the images have an entirely different biological meaning and treatment. Duplicating images in this way is ethically not acceptable. © 2019
Skin aging & cancer: Ambient UV-R exposure
(Springer Singapore, 2020) Ashish Dwivedi; Neeraj Agarwal; Lipika Ray; Amit Kumar Tripathi
This book summarizes the potent effect of ultraviolet radiation (UVR) on the photoaging and cancer formation. Skin is the largest human organ which continually reconstructs itself to ensure its viability, integrity, and ability to provide protection for the body. This protection can be compromised by the aging of the skin which ultimately promotes skin inflammation, impaired wound repair, and increased risk of skin cancer. The book entails mechanistic insights into the UVR-induced immunomodulation and DNA damage in the skin to delineate the pathogenesis, and develop novel ways for prevention of photoaging of the skin cells. It also elucidates the potential of nanotechnology in the treatment of skin cancer. Further, it discusses the bioinformatics approaches to understand the molecular mechanism of photoaging and cancer formation. © Springer Nature Singapore Pte Ltd. 2019.
Superior biomaterials using diamine modified graphene grafted polyurethane
(Elsevier Ltd, 2016) Dinesh K. Patel; Vivek Gupta; Ashish Dwivedi; Sanjeev K. Pandey; Vinod K. Aswal; Dipak Rana; Pralay Maiti
Surface modification of graphene oxide has been performed using diamine moieties with varying chain length and subsequently chemically grafted with long chain polyurethane for wrapping up of graphene sheet with large polymer chains. Functionalization of graphene and its subsequent grafting have been verified through spectroscopic measurements like NMR, FTIR and UV–visible spectroscopy and the uniform dispersion of graphene sheet in polyurethane matrix is achieved. Nanohybrids exhibit better thermal and mechanical responses along with greater self-assembly as compared to pure polymer. Nanometer dimension molecular sheet to gradual increased size of the order of tens of nanometer, hundreds of nanometer to micron scale assembly has been captured through XRD, small angle neutron scattering, AFM and optical microscopy, respectively. Nature of self-assembly associated with stronger interactions sustain the release of embedded drug (anticancerous dexamethasone) from nanohybrid and larger size of inhomogeinities for longer spacer length further sustain the drug release and thereby able to control the release rate of drug by articulating the chemistry of graphene modifications with suitable spacer length of diamine. Biocompatibility of the nanohybrids is verified with cell line studies using human breast cancer cells MDA-MB-231in terms of cell viability, cell adhesion, fluorescence image, reactive oxygen species and mitochondrial tracker measurements indicating better responses of nanohybrid vis-à-vis pure polyurethane. Thus, the control release of the dexamethasone drug from the nanohybrids along with better biological responses clearly suggests a novel biomaterial for the drug carrier. © 2016 Elsevier Ltd
Synergistic effect of graphene oxide coated nanotised apigenin with paclitaxel (GO-NA/PTX): A ROS dependent mitochondrial mediated apoptosis in ovarian cancer
(Bentham Science Publishers B.V., 2017) Manish Kumar Pal; Shyam Pyari Jaiswar; Ashish Dwivedi; Shruti Goyal; Vinay Nand Dwivedi; Anumesh Kumar Pathak; Vinod Kumar; Pushp Lata Sankhwar; Ratan Singh Ray
Background: Ovarian cancer is most lethal among all gynecologic malignancies. Paclitaxel (PTX) is well used chemotherapeutic regimen for cancer control; however its undesired toxicity has been a matter of concern for clinicians. Here, we used the graphene oxide coated nanotised apigenin (GO-NA) to enhance the efficacy of paclitaxel. Objective: The combined use of paclitaxel (PTX) and nanotised apigenin (NA) may reduce the PTX dose and increase the efficacy. Methods: GO and GO-Apigenin was prepared by modified Hummers method and the nanoparticles were characterized by dynamic light scattering and transmission electron microscopy. SKOV-3 cells were treated by DMSO, Group I (Control)-McCoy's 5A Medium, Group II-Paclitaxel (5nM), Group III- Nanotised Apigenin (GO-NA-10µM), Group IV- Paclitaxel (5nM) + GO-NA (10µM). Cell viability and IC-50 value were determined by MTT assay, synergism by Compusyn software, ROS by DCFH-DA assay, SOD activity by kit and MMP were examined by JC-1 and mitotracker/DAPI staining, cell cycle by flow cytometry, mRNA and protein level by Real Time-PCR and Western blot respectively Results: Results showed that GO-NA-PTX enhanced the anti-proliferative effect in synergistic manner as compare to GO-NA and PTX alone. GO-NA-PTX significantly suppressed the SOD activity, promotes the ROS accumulation, mitochondrial depolarization, DNA integrity and cell cycle arrest collectively accord the apoptosis. Results of immunocytochemistry, RT-PCR and western blot showed up-regulation of caspase-3, Bax, and down-regulation of Bcl-2. Conclusion: The combination of PTX with GO-NA produces synergistic effects in SKOV-3 cells via the modulation of pro and anti-apoptotic gene and may reduce side effects of PTX. © 2017 Bentham Science Publishers.
Synergistic effect of piperine and paclitaxel on cell fate via cyt-c, Bax/Bcl-2-caspase-3 pathway in ovarian adenocarcinomas SKOV-3 cells
(Elsevier B.V., 2016) Manish Kumar Pal; Shyama Pyari Jaiswar; Ajeet Kumar Srivastav; Shruti Goyal; Ashish Dwivedi; Ankit Verma; Jyoti Singh; Anumesh Kumar Pathak; Pushpa Lata Sankhwar; Ratan Singh Ray
Background and aims Ovarian cancer is fourth most common and lethal among all gynecologic malignancies. The chemotherapy usually requires in all stages of ovarian cancer but drugs have several side effects. We hypothesized that use of combination therapy of paclitaxel (PTX) and phytochemical piperine (PIP) may reduce the PTX dose as well as toxicity. The human ovarian adenocarcinomas SKOV3 cell treated with PTX-5 nM and PIP-10 µm after determination of IC50by MTT assay. Reactive oxygen species generation, mitochondrial membrane potential (MMP), DNA damage, cell death pathway markers as release of cyt-c, Bax/Bcl2-caspase-3 and cell cycle arrest were analyzed. The dose dependent treatment of SKOV-3 cells showed IC50and synergism at combination of 5 nM-PTX and 10 µm-PIP in cell viability assay. PTX and PIP increases the accumulation of reactive oxygen species which subsequently leading to increase in JC-1 and fragmented nuclei in mitotracker/DAPI staining. Comet assay showed 4.4-fold increase of tail formation in combined treated cells as compared to control. PTX-PIP arrests the cell cycle in sub-G1 phase. Immunocytochemistry of Bax showed increase in red fluorescence intensity whereas decrease in green fluorescence i.e Bax/Bcl-2 ratio increased. Moreover morphological EB/AO and Hoechst staining confirmed the enhanced apoptosis in combined treatment. Significant upregulation of apoptotic genes, cyt-c (3.4 fold) Bax (2.8 fold), caspase-3 (3.6 fold) whereas no change occurred in Bcl2 mRNA expression and protein expressions. The combination of PTX with PIP produces synergistic effects in SKOV-3 cells via the modulation of pro and anti-apoptotic gene and may compensate the toxicity and side effects of PTX. © 2016
Ultraviolet radiation (UVR): An introduction
(Springer Singapore, 2018) Ashish Dwivedi; Amit Kumar Tripathi; Jyoti Singh; Manish Kumar Pal
Radiant energy of sun is essential to perform metabolic processes of all flora and fauna on the earth. The electromagnetic radiations (EMR) emitted by sun extend from very long wavelength radiation, such as radiowaves (A ″' 3 x 108 m), to very short wavelength radiation, such as cosmic rays (A ″' 3 x 10-19 m). The EMR reaching at the earth surface contains wavelength from 290 to 4000 nm. However, the UV portion covers from 200 to 400 nm. The range from 200 to 400 nm is often arbitrarily categorized into UVA, UVB, and UVC radiation. Solar radiation less than 290 nm does not reach at the earth's surface due to the presence of O3 layer in stratospheric zone. But, last from few decades due to anthropogenic activities, the concentration of ozone layer decreases on stratospheric zone. As a consequence of that, UVB radiation levels are rising to 1% a year. Thus, the deleterious health effects on human beings (skin aging, cataracts, skin cancer, and immune suppression) are enhanced by UVR. © Springer Nature Singapore Pte Ltd. 2018.
Under ambient UVA exposure, pefloxacin exhibits both immunomodulatory and genotoxic effects via multiple mechanisms
(Elsevier B.V., 2018) Jyoti Singh; Ajeet K. Srivastva; Payal Mandal; Sonam Chandra; Divya Dubey; Ashish Dwivedi; Deepti Chopra; Anurag Tripathi; Ratan Singh Ray
Pefloxacin (PFLX) is an antibiotic, which shows broad spectrum antimicrobial activities. It is an important derivative of fluoroquinolones (FLQs) group. Ultraviolet radiation (200–400 nm) causes major problem for living being which comes at the earth surface naturally through sunlight and increasing regularly due to ozone depletion. PFLX was photodegraded in 5 h and forms photoproduct under UVA exposure. At the non photocytotoxic dose PFLX, shows reduced phagocytosis activity, NO (nitric oxide) production, large vacuole formation and down regulated IL-6, TNF-α and IL-1 in BALB/c macrophages at both genes and proteins levels. At higher doses (photocytotoxic doses), PFLX induced a concentration dependent decrease in cell viability of human keratinocyte cell line (HaCaT) and peritoneal macrophages of BALB/c mice. Our molecular docking suggests that PFLX binds only to the cleaved DNA in the DNA-human TOP2A complex. Topoisomerase assay confirmed that PFLX inhibits human topoisomerase by forming an adduct with DNA. Photosensitized PFLX also caused intracellular ROS mediated DNA damage and formation of micronuclei and cyclobutane pyrimidine dimers (CPDs). Increase intracellular ROS leads to apoptosis which was proved through lysosomal destabilization and reduced mitochondrial membrane potential (MMP). Our present study shows that ambient UVA exposure in the presence of PFLX caused immunomodulatory as well as photogenotoxic effects. Therefore, patients under PFLX drug treatment should avoid sunlight exposure, especially during peak hours for their photosafety. © 2017