The Anticancer Role of Capsaicin in Experimentallyinduced Lung Carcinogenesis.

OBJECTIVES: Capsaicin (CAP) is the chief pungent principle found in the hot red peppers and the chili peppers that have long been used as spices, food additives and drugs. This study investigated the anticancer potential of CAP through its ability to modify extracellular matrix components and proteases during mice lung carcinogenesis. METHODS: Swiss albino mice were treated with benzo(a) pyrene (50 mg/kg body weight dissolved in olive oil) orally twice a week for four successive weeks to induce lung cancer at the end of 14(th) week. CAP was administrated (10 mg/kg body weight dissolved in olive oil) intraperitoneally. Extracellular matrix components were assayed; Masson's trichome staining of lung tissues was performed. Western blot analyses of matrix metalloproteases 2 and 9 were also carried out. RESULTS: In comparison with the control animals, animals in which benzo(a)pyrene had induced lung cancer showed significant increases in extracellular matrix components such as collagen (hydroxy proline), elastin, uronic acid and hexosamine and in glycosaminoglycans such as hyaluronate, chondroitin sulfate, keratan sulfate and dermatan sulfate. The above alterations in extracellular matrix components were effectively counteracted in benzo(a)pyrene along with CAP supplemented animals when compared to benzo(a) pyrene alone supplemented animals. The results of Masson's trichome staining for collagen and of, immunoblotting analyses of matrix metalloproteases 2 and 9 further supported the biochemical findings. CONCLUSION: The apparent potential of CAP in modulating extracellular matrix components and proteases suggests that CAP plays a chemomodulatory and anti- cancer role working against experimentally induced lung carcinogenesis.

Mitigating role of baicalein on lysosomal enzymes and xenobiotic metabolizing enzyme status during lung carcinogenesis of Swiss albino mice induced by benzo(a)pyrene.

The lungs mainly serve as a primary site for xenobiotic metabolism and constitute an important defense mechanism against inhalation of carcinogens. Our current study aimed to evaluate the chemotherapeutic efficacy of baicalein (BE) in Swiss albino mice exposed to tobacco-specific carcinogen benzo(a)pyrene [B(a)P] for its ability to mitigate pulmonary carcinogenesis. Here, we report that altered activities/levels of lysosomal enzymes (cathepsin-D, cathepsin-B, acid phosphatase, ß-D-galactosidase, ß-D-glucuronidase, and ß-D-N-acetyl glucosaminidase), phase I biotransformation enzymes (cytochrome P450, cytochrome b5, NADPH-cytochrome P450 reductase, and NADH-cytochrome b5 reductase), and phase II enzymes (glutathione S-transferase, UDP-glucuronyl transferase, and DT-diaphorase) were observed in the B(a)P-induced mice. Treatment with BE significantly restored back the activities/levels of lysosomal enzymes, phase I and phase II biotransformation enzymes. Moreover, assessment of lysosomal abnormalities by transmission electron microscopic examination revealed that BE treatment effectively counteract B(a)P-induced oxidative damages. Protein expression levels studied by immunohistochemistry, immunofluorescence, and immunoblot analysis of CYP1A1 revealed that BE treatment effectively negate B(a)P-induced upregulated expression of CYP1A1. Further analysis of scanning electron microscopic studies in lung was carried out to substantiate the anticarcinogenic effect of BE. The overall data suggest that BE treatment significantly inhibits lysosomal and microsomal dysfunction, thus revealing its potent anticarcinogenic effect.

Baicalein abrogates reactive oxygen species (ROS)-mediated mitochondrial dysfunction during experimental pulmonary carcinogenesis in vivo.

Our current study aimed to evaluate the chemotherapeutic efficacy of baicalein (BE) in Swiss albino mice, which is exposed to benzo(a)pyrene [B(a)P] for its ability to alleviate mitochondrial dysfunction and systolic failure. Here, we report that oral administration of B(a)P (50 mg/kg body weight)-induced pulmonary genotoxicities in mice was assessed in terms of elevation in reactive oxygen species (ROS) generation and DNA damage in lung mitochondria. MDA-DNA adducts were formed in immunohistochemical analysis, which confirmed nuclear DNA damage. mRNA expression levels studied by RT-PCR analysis of voltage-dependent anion channel (VDAC) and adenine nucleotide translocase (ANT) were found to be significantly decreased and showed a marked increase in membrane permeability transition pore (MPTP) opening. Accompanied by up-regulated Bcl-xL and down-regulated Bid, Bim and Cyt-c proteins studied by immunoblot were observed in B(a)P-induced lung cancer-bearing animals. Administration of BE (12 mg/kg body weight) significantly reversed all the above deleterious changes. Moreover, assessment of mitochondrial enzyme system revealed that BE treatment effectively counteracts B(a)P-induced down-regulated levels/activities of isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, NADH dehydrogenase, cytochrome-C-oxidase and ATP levels. Restoration of mitochondria from oxidative damage was further confirmed by transmission electron microscopic examination. Further analysis of lipid peroxidation, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C in lung mitochondria was carried out to substantiate the antioxidant effect of BE. The overall data conclude that chemotherapeutic efficacy of BE might have strong mitochondria protective and restoration capacity in sub-cellular level against lung carcinogenesis in Swiss albino mice.

Potent antitumor and antineoplastic efficacy of baicalein on benzo(a)pyrene-induced experimental pulmonary tumorigenesis.

Current study aims to evaluate the efficacy of baicalein (BE), a naturally occurring bioactive flavanoid (5,6,7-trihydroxy-flavone), at a dose of 12 mg/kg body wt in Swiss albino mice exposed to tobacco-specific carcinogen benzo(a)pyrene [B(a)P] (50 mg/kg body wt) for its ability to mitigate pulmonary adenoma formation and growth. Under coarse observation, B(a)P-administered mice, after 16 weeks, developed macroscopically detectable tumors, whereas oral treatment with BE to the lung cancer-induced mice significantly reduced tumor incidence in 16-week pre- and posttreated groups. A detailed histopathological examination of lung was conducted to determine the degree of cancer progression. Incidence of anaplasia, hyperplasia, dysplasia, severe dysplasia, and adenocarcinoma were evident in carcinogen-administrated group in 6, 10, 12, 14, and 16th weeks, respectively, whereas these anomalies were effectively reduced after pre- and posttreatment with BE. In the pretreatment group, BE significantly arrested tumor multiplicity by approximately 65% and tumor load by approximately 88%, while in the posttreatment, the compound significantly reduced the tumor multiplicity by approximately 48% and tumor load by approximately 61%. Further analysis of serum tumor markers like carcinoembryonic antigen, CK 19 fragments (CYFRA 21-1), and tissue marker enzymes like aryl hydrocarbon hydroxylase, adenosine deaminase, γ-glutamyl transpeptidase, 5'-nucleotidase, and lactate dehydrogenase in serum and lung homogenate was carried out to substantiate the anticarcinogenic effect of BE. The overall data from our experiments suggested that BE significantly inhibited pulmonary adenoma formation and growth, thus revealing its potent antitumorigenic effect.

Antiproliferative and antioxidant potential of beta-ionone against benzo(a)pyrene-induced lung carcinogenesis in Swiss albino mice.

Nowadays, in developing countries like India, incidence of lung cancer is increasing rapidly, and as a consequence it has become the most common cause of malignancy-associated death. This study is aimed to evaluate the therapeutic efficacy of beta-ionone (ION), a precursor for carotenoids against benzo(a)pyrene [B(a)P]-induced lung carcinogenesis. B(a)P (50 mg/kg body weight, orally twice a week for 4 successive weeks)-induced lung cancer in mice was assessed both in tissue and serum in terms of increase LPO and tissue marker enzymes, such as aryl hydrocarbon hydroxylase, γ-glutamyl transpeptidase, 5'-nucleotidase, and lactate dehydrogenase, and serum tumor markers such as carcinoembryonic antigen and neuron-specific enolase with concordant decrease in activities of tissue enzymic and non-enzymic antioxidants were observed on the treatment of ION (60 mg/kg body weight, orally twice a week for 16 weeks) significantly attenuated LPO and restored all cancer marker enzymes and antioxidants levels to near normal, which indicates the anticancer effect of ION. This was further confirmed by histological staining of argyrophilic nucleolar organizer region and histopathological analysis of lung tissue, immunohistochemical and immunoblot analysis of proliferating cell nuclear antigen. Overall findings suggested that the ION effectively ameliorated the lung carcinogenesis, which is attributed to the antiproliferative and antioxidant potential through free radical scavenging property.