Manjula M Venkatappa

Dr. Manjula M Venkatappa

Deapartment of Pediatrics and Cardiology, Saint Louis University Hospital, St Louis, USA
orcid
Postdoctoral Researcher, Saint Louis University, USA

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

View All Publications
29 June 2023 in Molecules
Verified
Journal Article
Open access
PDF file
Manjula M VenkatappaManjula M Venkatappa
Manjula M Venkatappa
CUChikkappa Udagani
Chikkappa Udagani
SGSujatha M. Hanume Gowda
Sujatha M. Hanume Gowda
SVShivakumar Venkataramaiah
Shivakumar Venkataramaiah
RCRyan Casini
Ryan Casini
HEHosam O. Elansary
Hosam O. Elansary
Oxidative stress and chronic inflammation interplay with the pathogenesis of cancer. Breast cancer in women is the burning issue of this century, despite chemotherapy and magnetic therapy. The management of secondary complications triggered by post-chemotherapy poses a great challenge. Thus, identifying target-specific drugs with anticancer potential without secondary complications is a challenging task for the scientific community. It is possible that green technology has been employed in a greater way in order to fabricate nanoparticles by amalgamating plants with medicinal potential with metal oxide nanoparticles that impart high therapeutic properties with the least toxicity. Thus, the present study describes the synthesis of Titanium dioxide nanoparticles (TiO2 NPs) using aqueous Terenna asiatica fruit extract, with its antioxidant, anti-inflammatory and anticancer properties. The characterisation of TiO2 NPs was carried out using a powdered X-ray diffractometer (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray diffraction (EDX), high-resolution transmission electron microscopy (HR-TEM), dynamic light scattering (DLS), and zeta-potential. TiO2 NPs showed their antioxidant property by scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals in a dose-dependent manner with an IC50 value of 80.21 µg/µL. To ascertain the observed antioxidant potential of TiO2 NPs, red blood cells (RBC) were used as an in vitro model system. Interestingly, TiO2 NPs significantly ameliorated all the stress parameters, such as lipid peroxidation (LPO), protein carbonyl content (PCC), total thiol (TT), superoxide dismutase (SOD), and catalase (CAT) in sodium nitrite (NaNO2)-induced oxidative stress, in RBC. Furthermore, TiO2 NPs inhibited RBC membrane lysis and the denaturation of both egg and bovine serum albumin, significantly in a dose-dependent manner, suggesting its anti-inflammatory property. Interestingly, TiO2 NPs were found to kill the MCF-7 cells as a significant decrease in cell viability of the MCF-7 cell lines was observed. The percentage of growth inhibition of the MCF-7 cells was compared to that of untreated cells at various doses (12.5, 25, 50, 100, and 200 µg/mL). The IC50 value of TiO2 NPs was found to be (120 µg/mL). Furthermore, the Annexin V/PI staining test was carried out to confirm apoptosis. The assay indicated apoptosis in cancer cells after 24 h of exposure to TiO2 NPs (120 µg/mL). The untreated cells showed no significant apoptosis in comparison with the standard drug doxorubicin. In conclusion, TiO2 NPs potentially ameliorate NaNO2-induced oxidative stress in RBC, inflammation and MCF-7 cells proliferation.

12 August 2022 in Molecules
Verified
Journal Article
Open access
PDF file
Manjula M VenkatappaManjula M Venkatappa
Manjula M Venkatappa
CUChikkappa Udagani
Chikkappa Udagani
SHSujatha M. Hanumegowda
Sujatha M. Hanumegowda
SPSiddanakoppalu N Pramod
Siddanakoppalu N Pramod
SVShivakumar Venkataramaiah
Shivakumar Venkataramaiah
DSDevaraja Sannaningaiah
Devaraja Sannaningaiah
The present study describes the green biofunctional synthesis of magnesium oxide (MgO) nanoparticles using the aqueous Tarenna asiatica fruit extract. The characterization of Tarenna asiatica fruit extract MgO nanoparticles (TAFEMgO NPs) was achieved by X-ray powder diffraction, UV-Vis spectroscopy, FTIR, TEM, SEM, and energy-dispersive X-ray diffraction. TAFEMgO NPs scavenged the DPPH free radicals with an IC50 value of 55.95 μg/μL, and it was highly significant compared to the standard. To authenticate the observed antioxidant potential of TAFEMgO NPs, oxidative stress was induced in red blood cells (RBC) using sodium nitrite (NaNO2). Interestingly, TAFEMgO NPs ameliorated the RBC damage from oxidative stress by significantly restoring the stress parameters, such as the protein carbonyl content (PCC), lipid peroxidation (LPO), total thiol (TT), super-oxide dismutase (SOD), and catalase (CAT). Furthermore, oxidative stress was induced in-vivo in Sprague Dawley female rats using diclofenac (DFC). TAFEMgO NPs normalized the stress parameters in-vivo and minimized the oxidative damage in tissues. Most importantly, TAFEMgO NPs restored the function and architecture of the damaged livers, kidneys, and small intestines by regulating biochemical parameters. TAFEMgO NPs exhibited an anticoagulant effect by increasing the clotting time from 193 s in the control to 885 s in the platelet rich plasma. TAFEMgO NPs prolonged the formation of the clot process in the activated partial thromboplastin time and the prothrombin time, suggest the effective involvement in both intrinsic and extrinsic clotting pathways of the blood coagulation cascade. TAFEMgO NPs inhibited adenosine di-phosphate (ADP)-induced platelet aggregation. TAFEMgO NPs did not show hemolytic, hemorrhagic, and edema-inducing properties at the tested concentration of 100 mg/kgbody weight, suggesting its non-toxic property. In conclusion, TAFEMgO NPs mitigates the sodium nitrite (NaNO2)- and diclofenac (DFC)-induced stress due to oxidative damage in both in vitro and in vivo experimental models.

24 October 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
VMVANI K M
VANI K M
MVMANJULA M Venkatappa
MANJULA M Venkatappa
Manjula M VenkatappaManjula M Venkatappa
Manjula M Venkatappa
DSDevaraja Sannaningaiah
Devaraja Sannaningaiah
Ellagitannins (ETs) are the group of tannins found in fruits, nuts and seeds; they undergo hydrolysis in the human digestive tract to form ellagic acid (EA). EA further converted into various forms of Urolithin derivatives (A, B, C, D, M-5, M-6 and M-7) by gut micro biota. Perhaps, the pharmacological properties of said Urolithins were extensively studied, while, little is known about the therapeutic role of synthetic Urolithin-C on oxidative stress induced eryptosis and tissue damage. Therefore, in the current study we investigated the ameliorative role of chemically syn-thesized Urolithin-C on sodium nitrite and Diclofenac (DFC) induced eryptosis and vital organ damage respectively. Urolithin-C was synthesized using chemical method and characterized by High-Performance Liquid Chromatography (HPLC), Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FTIR), and Liquid Chromatography Mass Spectroscopy (LC-MS). The synthesized Urolithin-C scavenged free radicals (DPPH, H2O2) and reduced ferric iron to ferrous iron, revealed its antioxidant activity. The observed antioxidant potential of Uro-lithin-C was investigated in sodium nitrite induced stress in RBC and Diclofenac induced tissue damage in rats. Interestingly, Urolithin-C normalized the sodium nitrate-induced oxidative stress in red blood cells by regulating stress markers, such as lipid peroxidation (LPO), total thiol (TT), and protein carbonyl content (PCC), and endogenous antioxidant enzymes superoxide dis-mutase (SOD) and catalase (CAT) in a dose dependent manner. Similar effect was also observed in the tissue homogenates of liver, kidney, heart and pancreas taken from the Diclofenac injected Sprague Dawley rats. The tissue sections (liver, kidney, heart and pancreas) obtained from the Diclofenac (DFC) received rats showed massive destruction of hepatocytes, nephrons, cardiocytes and pancreas. However, Urolithin-C received rats tissue sections showed normal histology compared to the positive (Silymarin) control treated groups. In addition, Urolithin-C regulated the key tissue specific biochemical markers in DFC injected Sprague Dawley rats serum strengthened its tissue protective role. In conclusion, chemically synthesized Urolithin-C regulated NaNO2 and diclofenac induced oxidative stress in RBC and vital organs through its antioxidant property.