Urtica dioica Induces Cytotoxicity in
Human Prostate Carcinoma LNCaP Cells: Involvement of
Oxidative Stress, Mitochondrial Depolarization and
Apoptosis
Arkene Levy1*, Dhandayuthapani
Sivanesan2, Rajeswari
Murugan3, Jackie Jornadal3,
Yanira Quinonez3, Mark
Jaffe3 and Appu Rathinavelu2
1Pharmacology Section,
Department of Basic Medical Sciences, University of the
West Indies, Mona Campus, Jamaica, 2Rumbaugh
Goodwin Institute for Cancer Research, Nova Southeastern
University. 1850 NW 69th Ave, Suite 5 Plantation, FL
33313, 3Nova Southeastern University,
3301 College Ave Fort Lauderdale, FL 33314, USA,
*For correspondence:
Email:
arkene_levy@yahoo.com; Tel:
1876-288-6040; Fax: 1876-977-3823,
Received: 13 November 2012
Revised accepted: 6 April
2014
Tropical
Journal of Pharmaceutical Research, May 2014;
13(5): 711-717
Abstract
Purpose: To evaluate the cytotoxic
mechanisms of an extract from the leaves of the Urtica
dioica (UD) plant in LNCaP prostate cancer cells.
Methods: LNCaP cells were exposed to
the UD extract for 24hrs and cell viability assessed
using the MTT assay. Reactive oxygen species generation
was assessed using the NBT assay and mitochondrial
membrane potential using JCI-aggregation. DNA
fragmentation patterns and cleavage of poly (ADP-ribose)
polymerase were assessed using western blot and caspase
activation via colorimetric assay.
Results: The viability of LNCaP
cells was significantly decreased in a dose-dependent
manner following 24-h treatment with the UD extract. The
reactive oxygen species levels were also significantly
increased and mitochondrial depolarization was evident.
DNA fragmentation, PARP cleavage and an increase in the
activities of caspases 3 and 9 were observed in cells
treated with the UD extract and this confirmed the
induction of apoptosis as the major cytotoxic modality
for this extract.
Conclusion:
The results confirm that the
cytotoxic activity of UD aqueous extract in LNCaP cells
is mediated through oxidative stress and apoptosis.
These findings could hold positive implications for the
potential use of UD extract in prostate cancer therapy.
Keywords: Urtica dioica,
Cytotoxicity, DNA fragmentation, PARP cleavage, Caspases,
Prostate cancer
