(P < 0.05) especially in a diet containing 10 and 15% RBO. Similarly, Panala et al.
(2009) reported that bioactive constituents present in RBO (7 or 14%) inhibit the
growth of the cancer cells; therefore, the tumor formation was decreased in RBO diet
fed to azoxymethane-treated rats compared to control diet (formulations of diets
based on AIN-93G) after 45 weeks. The outcome was correlated with the presence of
tocopherols, tocotrienols, squalene, γ-oryzanol, inositol hexaphosphate (IP6), phytosterols, etc., present in RBO. Phytic acid, a natural antioxidant, present in rice bran
is known to inhibit the formation of hydroxyl radicals (HO). Transformation of a
normal cell into cancer cells involves a metal-mediated reaction, triggered by the
presence of iron. Potentially reactive iron may present in large amount in the
intestine (specifically in a population consuming red meat). It probably suppresses
the iron-mediated step during the formation of cancer (Graf and Eaton 1993). In an
experimental model, rats were treated with azoxymethane (a potent carcinogen) and
fed on phytic acid (0.2% w/v) extracted from RBO and it resulted in a reduction in
colon tumor formation and thus, showed the potency of RBO in reducing colon
cancer (Norazalina et al. 2010). Iqbal et al. (2003) revealed the chemopreventive
activity of diet loaded with TRF of RBO against breast cancer carcinogen 7,12dimethylbenzanthracene (DMBA, a chemical carcinogen known to induce mammary carcinogenesis). Feeding of TRF (10 mg/kg body weight/day) for 6 months to
DMBA-administered rats, reduced the severity of neoplastic transformations and
was indicative of lower carcinogen-stimulated tissue damage.
Kong et al. (2009) studied the topical application of cycloartenyl ferulate (CF), a
phenolic compound extracted from RBO to inhibit cancer (cell lines SW480 and
SW620) in mice in vitro growth inhibition on human colorectal adenocarcinoma
SW480. The mechanism linked with CF-induced chemoprevention was established
by in vitro SW480 CRC cell line. The study exhibited the capacity of CF to elicit
apoptosis in SW480 cells via activation of caspase-protein (enhanced activation of
caspase-8 and -3) in both extrinsic and intrinsic pathways. Further, the growth and
survival of normal colon CCD-18-Co cells were supported by CF.
Physical exercise is commonly predicted to have a positive impact on the
physiological functions of the body and it promotes overall well-being. Health
benefits of exercises are huge and already known but exhaustive exercise might
create oxidative stress. Excessive exercise creates oxidative stress in the body due to
the imbalance between antioxidants concentration and free radicals (Urso and
Clarkson 2003). Ismail et al. (2010) designed an exercise program to induce oxidative stress in rats. The rats of the same sex, weight, and strain had performed
swimming exercise 60 min/day, for 5 days in a week and continued for a period of
10 weeks. The gamma-oryzanol rich fraction (ORF) was extracted and fractionated
from rice bran using supercritical fluid extraction (SFE) and given to rats to study the
effect on antioxidant and oxidative stress related genes in liver. The results revealed
that animals treated with ORF emulsion had strong antioxidant activity (upregulated
the antioxidant genes) and had the potential to downregulate gene expression linked
with oxidative stress when compared with commercially available gamma-oryzanol
preparations.
408
U. Yadav et al.
(2009) reported that bioactive constituents present in RBO (7 or 14%) inhibit the
growth of the cancer cells; therefore, the tumor formation was decreased in RBO diet
fed to azoxymethane-treated rats compared to control diet (formulations of diets
based on AIN-93G) after 45 weeks. The outcome was correlated with the presence of
tocopherols, tocotrienols, squalene, γ-oryzanol, inositol hexaphosphate (IP6), phytosterols, etc., present in RBO. Phytic acid, a natural antioxidant, present in rice bran
is known to inhibit the formation of hydroxyl radicals (HO). Transformation of a
normal cell into cancer cells involves a metal-mediated reaction, triggered by the
presence of iron. Potentially reactive iron may present in large amount in the
intestine (specifically in a population consuming red meat). It probably suppresses
the iron-mediated step during the formation of cancer (Graf and Eaton 1993). In an
experimental model, rats were treated with azoxymethane (a potent carcinogen) and
fed on phytic acid (0.2% w/v) extracted from RBO and it resulted in a reduction in
colon tumor formation and thus, showed the potency of RBO in reducing colon
cancer (Norazalina et al. 2010). Iqbal et al. (2003) revealed the chemopreventive
activity of diet loaded with TRF of RBO against breast cancer carcinogen 7,12dimethylbenzanthracene (DMBA, a chemical carcinogen known to induce mammary carcinogenesis). Feeding of TRF (10 mg/kg body weight/day) for 6 months to
DMBA-administered rats, reduced the severity of neoplastic transformations and
was indicative of lower carcinogen-stimulated tissue damage.
Kong et al. (2009) studied the topical application of cycloartenyl ferulate (CF), a
phenolic compound extracted from RBO to inhibit cancer (cell lines SW480 and
SW620) in mice in vitro growth inhibition on human colorectal adenocarcinoma
SW480. The mechanism linked with CF-induced chemoprevention was established
by in vitro SW480 CRC cell line. The study exhibited the capacity of CF to elicit
apoptosis in SW480 cells via activation of caspase-protein (enhanced activation of
caspase-8 and -3) in both extrinsic and intrinsic pathways. Further, the growth and
survival of normal colon CCD-18-Co cells were supported by CF.
Physical exercise is commonly predicted to have a positive impact on the
physiological functions of the body and it promotes overall well-being. Health
benefits of exercises are huge and already known but exhaustive exercise might
create oxidative stress. Excessive exercise creates oxidative stress in the body due to
the imbalance between antioxidants concentration and free radicals (Urso and
Clarkson 2003). Ismail et al. (2010) designed an exercise program to induce oxidative stress in rats. The rats of the same sex, weight, and strain had performed
swimming exercise 60 min/day, for 5 days in a week and continued for a period of
10 weeks. The gamma-oryzanol rich fraction (ORF) was extracted and fractionated
from rice bran using supercritical fluid extraction (SFE) and given to rats to study the
effect on antioxidant and oxidative stress related genes in liver. The results revealed
that animals treated with ORF emulsion had strong antioxidant activity (upregulated
the antioxidant genes) and had the potential to downregulate gene expression linked
with oxidative stress when compared with commercially available gamma-oryzanol
preparations.
408
U. Yadav et al.