Reji Manjunathan

Reji Manjunathan


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2021 in Critical Reviews in Oncology/Hematology
Verified
Journal Article
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NDNALINI DEVARAJAN
NALINI DEVARAJAN
RMReji Manjunathan
Reji Manjunathan
GKG Senthil Kumar
G Senthil Kumar

16 May 2022 in BMC Bioinformatics
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Journal Article
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RMReji Manjunathan
Reji Manjunathan
VPVijayalakshmi Periyaswami
Vijayalakshmi Periyaswami
KMKartik Mitra
Kartik Mitra
ARArokiaraj Sherlin Rosita
Arokiaraj Sherlin Rosita
MPMedha Pandya
Medha Pandya
MDMukesh Doble
Mukesh Doble
Background: The Transmembrane Serine Protease 2 (TMPRSS2) of human cell plays a significant role in proteolytic cleavage of SARS-Cov-2 coronavirus spike protein and subsequent priming to the receptor ACE2. Approaching TMPRSS2 as a therapeutic target for the inhibition of SARS-Cov-2 infection is highly promising. Hence, in the present study, we docked the binding efficacy of ten naturally available phyto compounds with known anti-viral potential with TMPRSS2. The aim is to identify the best phyto compound with a high functional affinity towards the active site of the TMPRSS2 with the aid of two different docking software. Molecular Dynamic Simulations were performed to analyse the conformational space of the binding pocket of the target protein with selected molecules. Results: Docking analysis using PyRx version 0.8 along with AutoDockVina reveals that among the screened phyto compounds, Genistein shows the maximum binding affinity towards the hydrophobic substrate-binding site of TMPRSS2 with three hydrogen bonds interaction ( − 7.5 kcal/mol). On the other hand, molecular docking analysis using Schrodinger identified Quercetin as the most potent phyto compound with a maximum binding affinity towards the hydrophilic catalytic site of TMPRSS2 ( − 7.847 kcal/mol) with three hydrogen bonds interaction. The molecular dynamics simulation reveals that the Quercetin-TMPRSS complex is stable until 50 ns and forms stable interaction with the protein ( − 22.37 kcal/mol of MM-PBSA binding free energy). Genistein creates a weak interaction with the loop residues and hence has an unstable binding and exits from the binding pocket. Conclusion: The compounds, Quercetin and Genistein, can inhibit the TMPRSS2 guided priming of the spike protein. The compounds could reduce the interaction of the host cell with the type I transmembrane glycoprotein to prevent the entry of the virus. The critical finding is that compared to Genistein, Quercetin exhibits higher binding affinity with the catalytic unit of TMPRSS2 and forms a stable complex with the target. Thus, enhancing our innate immunity by consuming foods rich in Quercetin and Genistein or developing a novel drug in the combination of Quercetin and Genistein could be the brilliant choices to prevent SARS-Cov-2 infection when we consider the present chaos associated with vaccines and anti-viral medicines.

6 June 2015 in Biological Procedures Online
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RMReji Manjunathan
Reji Manjunathan
MRMalathi Ragunathan
Malathi Ragunathan
Osteosarcoma is the most common primary tumor that affects usually children. Due to its cellular complex and osteoid formation it is very difficult to understand the mechanism behind the progressiveness of osteosarcoma. Various animal models are available to study the issue but they are time consuming and costly. We aimed to understand the progressiveness and invasiveness of osteosarcoma induced by SaOS2 cells using chicken chorioallantoic membrane. CAM is a well-established model which allows in vivo studies of tumor induced angiogenesis and the testing of anti angiogenic molecules. However only a few reports showed the tumor forming ability of SaOS2 cells on CAM. Angiogenic ability of SaOS2 cells on CAM was validated by various methods. Angiogenic ability was scored by direct visualization and scanning microscopic analysis. The sprouting ability and growth of the vessel was measured by Angioquant software under different cellular volume. The invasiveness was analyzed by histological staining. Involvement of angiogenic factors at differential stage of progressiveness was confirmed by the molecular and protein level expression analysis. SaOS2 cells induces sprouting angiogenesis on CAM and shows its aggressiveness by rupturing the ectodermal layer of the CAM. Growth and development of osteosarcoma depends mainly on the activation of VEGF165, MMP2 and MMP9. CAM able to reproduce angiogenic response against the stimulation of SaOS2 cells exactly as in other animal models without inflammatory reactions. CAM is an excellent alternative in vivo model for studying the aggressiveness and tumor progression of osteosarcoma using various angiogenic techniques in an easily, faster and affordable way. We further provided insight about the involvement of various angiogenic growth factors on the development of osteosarcoma which will enable to find the suitable therapeutic molecule for the treatment of osteosarcoma. CAM model could provide a wide space using modern techniques like micro array or in situ hybridization to have a better understanding about the progression and invasiveness of osteosarcoma cells to develop suitable therapeutic molecules.

27 November 2021 in Antioxidants
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SJSelvaraj Jayaraman
Selvaraj Jayaraman
ARAnitha Roy
Anitha Roy
DVDr. Srinivasan V
Dr. Srinivasan V
RSRamya sekar
Ramya sekar
VVVishnu Priya Veeraraghavan
Vishnu Priya Veeraraghavan
RMReji Manjunathan
Reji Manjunathan
Diabetes is one of the most significant health issues across the world. People identified with diabetes are more vulnerable to various infections and are at a greater risk of developing cardiovascular diseases. The plant-based food we consume often contains many sterol-based bioactive compounds. It is well documented that these compounds could effectively manage the processes of insulin metabolism and cholesterol regulation. Insulin resistance followed by hyperglycemia often results in oxidative stress level enhancement and increased reactive oxygen species production. At the molecular level, these changes induce apoptosis in pancreatic cells and hence lead to insulin insufficiency. Studies have proved that plant sterols can lower inflammatory and oxidative stress damage connected with DNA repair mechanisms. The effective forms of phyto compounds are polyphenols, terpenoids, and thiols abundant in vegetables, fruits, nuts, and seeds. The available conventional drug-based therapies for the prevention and management of diabetes are time-consuming, costly, and with life-threatening side effects. Thereby, the therapeutic management of diabetes with plant sterols available in our daily diet is highly welcome as there are no side effects. This review intends to offer an overview of the present scenario of the anti-diabetic compounds from food ingredients towards the therapeutic beneficial against diabetes.

10 June 2015 in Biological Research
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RMReji Manjunathan
Reji Manjunathan
MRMalathi Ragunathan
Malathi Ragunathan
Leptin, the cytokine produced by white adipose tissue is known to regulate food energy homeostasis through its hypothalamic receptor. In vitro studies have demonstrated that leptin plays a major role in angiogenesis through binding to the receptor Ob-R present on ECs by stimulating and initiating new capillary like structures from ECs. Various in vivo studies indicate that leptin has diverse effect on angiogenesis. A few reports have showed that leptin exerts pro angiogenic effects while some suggested that it has antiangiogenic potential. It is theoretically highly important to understand the effect of leptin on angiogenesis to use as a therapeutic molecule in various angiogenesis related pathological conditions. Chicken chorio allantoic membrane (CAM) on 9th day of incubation was incubated with 1, 3 and 5 μg concentration of HRL for 72 h using gelatin sponge. Images where taken after every 24 h of incubation and analysed with Angioguant software. The treated area was observed under microscope and histological evaluation was performed for the same. Tissue thickness was calculated morphometrically from haematoxylin and eosin stained cross sections. Reverse transcriptase PCR and immunohistochemistry were also performed to study the gene and protein level expression of angiogenic molecules. HRL has the ability to induce new vessel formation at the treated area and growth of the newly formed vessels and cellular morphological changes occur in a dose dependent manner. Increase in the tissue thickness at the treated area is suggestive of initiation of new capillary like structures. Elevated mRNA and protein level expression of VEGF165 and MMP2 along with the activation of ECs as demonstrated by the presence of CD34 expression supports the neovascularization potential of HRL. Angiogenic potential of HRL depends on the concentration and time of incubation and is involved in the activation of ECs along with the major interaction of VEGF 165 and MMP2. It is also observed that 3 μg of HRL exhibits maximum angiogenic potential at 72 h of incubation. Thus our data suggest that dose dependent angiogenic potential HRL could provide a novel role in angiogenic dependent therapeutics such as ischemia and wound healing conditions.

7 March 2023 in Journal of Biomolecular Structure and Dynamics
Verified
Journal Article
Closed access
LRLokesh Ravi
Lokesh Ravi
SGShabari Girish
Shabari Girish
SDSharun Roy D’sOuza
Sharun Roy D’sOuza
ABAnirudh Sreenivas Bk
Anirudh Sreenivas Bk
SGShree Kumari Gr
Shree Kumari Gr
RMReji Manjunathan
Reji Manjunathan
The study aims to identify and validate a potential α-Amylase inhibitor from the leaf extract of the Parthenium hysterophorus. Molecular docking and dynamics analyses were performed to test the anti-diabetic efficacy of the compound by focusing on α-Amylase inhibition. The molecular docking study using AutoDock Vina (PyRx) and SeeSAR tools identified β-Sitosterol as an effective α-Amylase inhibitory compound. Among the analysed fifteen phytochemicals, β-Sitosterol demonstrated the most appreciable binding energy (-9.0 Kcal/mol) and is comparatively higher than the binding energy of the standard α-Amylase inhibitor, the Acarbose (-7.6 Kcal/mol). The significance of the interaction between β-Sitosterol and α-Amylase was further investigated using Molecular Dynamics Simulation (MDS) for 100 ns via GROMACS. The data reveals that the compound could exhibit the highest stability with α-Amylase regarding RMSD, RMSF, SASA and Potential Energy analysis. The key residue of α-Amylase (Asp −197) shows a significantly low fluctuation of 0.7 Å while interacting with β-Sitosterol. The data obtained from MDS results strongly suggested the potential inhibitory impact of β-Sitosterol on α-Amylase. In addition, the proposed phytochemical was purified from the leaf extracts of P.hysterophorus using the silica gel column chromatography and identified by GC-MS analysis. The purified β-Sitosterol demonstrated a significant 42.30% in-vitro α-Amylase enzyme inhibition property under 400 µg/ml concentration and thus supported the in-silico predictions. Further in-vivo investigations are necessary to analyse the efficiency of β-Sitosterol on α-Amylase inhibition to help the anti-diabetic potential of the phytocompound. Communicated by Ramaswamy H. Sarma