Thymoquinone protects thioacetamide-induced chronic liver injury by inhibiting TGF-ß1/Smad3 axis in rats.

Chronic liver injury due to various etiological factors results in excess secretion and accumulation of extracellular matrix proteins, leading to scarring of liver tissue and ultimately to hepatic fibrosis. If left untreated, fibrosis might progress to cirrhosis and even hepatocellular carcinoma. Thymoquinone (TQ), an active compound of Nigella sativa, has been reported to exhibit antioxidant, anti-inflammatory and anticancer activities. Therefore, the effect of TQ against thioacetamide (TAA)-induced liver fibrosis was assessed in rats. Fibrosis was induced with intraperitoneal administration of TAA (250 mg/kg b.w.) twice a week for 5 weeks. TQ (20 mg/kg b.w.) and silymarin (50 mg/kg b.w.) were orally administered daily for 5 weeks separately in TAA administered groups. Liver dysfunction was reported by elevated liver enzymes, increased oxidative stress, inflammation and fibrosis upon TAA administration. Our study demonstrated that TQ inhibited the elevation of liver marker enzymes in serum. TQ administration significantly increased antioxidant markers, such as superoxide dismutase, catalase, glutathione, glutathione peroxidase and glutathione reductase in the liver tissue of rats. Further, TQ significantly attenuated liver fibrosis, as illustrated by the downregulation of TAA-induced interleukin-ß, tumour necrosis factor-α, inducible nitric oxide synthase and fibrosis markers like transforming growth factor-ß (TGF-ß), α-smooth muscle actin, collagen-1, Smad3 and 7. Therefore, these findings suggest that TQ has a promising hepatoprotective property, as indicated by its potential to effectively suppress TAA-induced liver fibrosis in rats by inhibiting oxidative stress and inflammation via TGF-ß/Smad signaling.

Molecular Targets of Nimbolide for Anti-Cancer Therapy: An Updated Review.

Cancer is a major cause of death worldwide with an increasing incidence rate and is considered a major public health problem. Distance metastasis to other tissues, high toxicity, and drug resistance of cancer cells to chemotherapy demand novel therapeutic approaches to treat cancer. Natural compounds from medicinal plants have been studied for therapeutic use in various malignancies. Nimbolide is an active principal compound from Azadirachta indica, which is an Asian traditional medicinal plant utilized historically as a remedy for a variety of diseases due to its antioxidant, anti-inflammatory, anti-cancer, and antimicrobial properties. It is a limonoid triterpene possessing potent anti-cancer effects in various types of cancers. It has been reported to induce multiple cytotoxic effects in tumor cells by modulating the cell proliferation, cell cycle, apoptosis, and metastasis by altering the various molecular signaling pathways. In the present review, we summarized all the in vitro and in vivo studies reporting the molecular targets of nimbolide for the therapeutic approaches in different types of cancer cells. We analyzed research publications up to September 2021 on the effect of nimbolide in various malignancies and the molecular mechanism of action. Nimbolide targets different signaling pathways including epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), insulin like growth factor (IGF), Wingless and INT-1 (Wnt)/ß-catenin, mitogen-activated protein kinases (MAPK)/c-Jun N-terminal kinases (JNK), phosphoinositide 3-kinase (PI3K)/AKT, tumor necrosis factor-α (TNF-α)/nuclear factor kappa B (NF-κß), and death receptor 5 (DR5) in several cancer cells. Nimbolide's widespread availability and absence of side effects, as well as understanding the molecular mechanism of nimbolide's action, will be useful to develop a therapeutic agent against cancer.

A flavonoid rich standardized extract of Glycyrrhiza glabra protects intestinal epithelial barrier function and regulates the tight-junction proteins expression.

BACKGROUND: Intestinal epithelial barrier dysfunction predisposes to many gastrointestinal, metabolic, and psychological disorders. A flavonoid rich extract of Glycyrrhiza glabra (FREG) has previously been reported to possess anti-inflammatory, antioxidant, and antiulcer properties. AIM: To investigate the effect of FREG (GutGard®) on restoring intestinal barrier function in tumor necrosis factor-alpha (TNF-α) stimulated human colonic adenocarcinoma cell monolayer (Caco-2) and 2,4,6-Trinitrobenzenesulfonic acid (TNBS) induced ulcerative colitis in rats. METHODS: In in vitro, human intestinal Caco-2 cell monolayers were treated with TNF-α in the presence or absence of FREG and the paracellular permeability to FITC-conjugated 4-kD dextran (FD4) was measured to evaluate protection against the barrier dysfunction. In in vivo, intestinal barrier dysfunction was induced in male albino Wistar rats via intrarectal instillation of TNBS. Subsequently, the rats were treated orally with either FREG at 6.25, 12.5, and 25 mg/kg body weight, or Mesacol (250 mg/kg) for 5 days. On day 5, intestinal epithelial permeability was assessed with FD4 leakage into the serum. Also, colonic inflammation, colon morphology, histology and macroscopic score, weight to length ratio were evaluated. The activity of myeloperoxidase (MPO), TNF- α, secretory IgA levels and tight junction proteins expression were evaluated in rat's colon. RESULTS: FREG protected the intestinal epithelial barrier integrity in human intestinal Caco-2 cells in vitro. FREG administration significantly improved the intestinal epithelial barrier function as evident from significant reduction in FD4 leakage. The colon morphology, histology score, macroscopic score, colon weight to length ratio also indicates beneficial effects of FREG on barrier function. In addition, FREG regulated the tight junction proteins, and markedly decreased TNF-α, MPO levels and significantly increased the secretory IgA levels in TNBS induced colitis rats. CONCLUSION: The study findings support the protective action of FREG on intestinal epithelial barrier integrity indicating its potential in protecting from implications of leaky gut.

Quercetin Inhibits the Epithelial to Mesenchymal Transition through Suppressing Akt Mediated Nuclear Translocation of ß-Catenin in Lung Cancer Cell Line.

Lung cancer is a first leading cause of cancer related death worldwide. Quercetin (QUE) has chemo-preventive effect against a variety of cancers. However, the molecular mechanism of QUE mediated inhibition of cancer cell migration and epithelial to mesenchymal transition (EMT) is not clear in lung cancer. Therefore, this study investigates the effect of QUE on EMT and metastasis of lung cancer cell line (A549). The MTT assay, scratch wound healing assay, Transwell migration and invasion assay performed to assess the cell viability and migration potential of lung cancer cells after treatment with different concentration of QUE. Further, chemokines gene expression was analyzed by qPCR and EMT markers were analyzed by immunocytochemistry and Western blot. QUE inhibits cell viability in a dose-dependent (10-80 µM) manner both at 24 and 48 h treatment. The Akt/MAPK/ß-catenin and EMT marker protein expressions were decreased significantly, whereas TIMP-2 expression was increased upon QUE treatment. QUE inhibits cell migration and invasion of A-549 cells. In addition, Immunocytochemistry result showed that QUE can reduce nuclear translocalisation of ß-catenin in A549 cells. Our results suggest that QUE can inhibit the metastatic potential in lung cancer by altering the Akt/MAPK/ß-catenin signaling pathway and inhibiting the nuclear translocation of ß-catenin.

The ambiguous role of sirtuins in head and neck squamous cell carcinoma.

Oral cancer is one of the most leading cancer responsible for significant morbidity and mortality. The sirtuins (SIRTs) are a family of class III histone deacetylases and are known to regulate a variety of molecular signaling associated with different cancer types including oral malignancies. SIRT1 acts as bifunctional in a variety of cancer. In oral cancer, SIRT1 seems to work as a tumor suppressor. The carcinogenic potential of SIRT1 is also reported in oral cancer, and hence, its role is still ambiguous. SIRT2 is also said to play a dual-faced role in different types of cancers. However, in oral cancer, SIRT2 is not studied and its role remains obscure. SIRT3 expression was positively correlated with oral malignancies. However, studies also showed the anti-cancer role of SIRT3 in oral cancer. SIRT7 loss was observed in oral cancer cells, while its overexpression caused the suppression of oral cancer cells proliferation, migration, and invasiveness. The role of other SIRTs in oral cancer was studied meagerly or reports not available. To date, only the roles of SIRT1, SIRT3, and SIRT7 have been reported in oral malignancies. Therefore, understanding the regulatory mechanisms employed by sirtuins to modulate oral cancer is important for developing potential anti-cancer therapeutic strategies.

Boldine treatment protects acetaminophen-induced liver inflammation and acute hepatic necrosis in mice.

Drug-induced liver injury (DILI) is a frequent cause responsible for acute liver failure (ALF). Acetaminophen (APAP) is a known hepatotoxin predictably causing intrinsic DILI. At high doses, APAP causes acute liver necrosis and responsible for ALF and liver transplant cases in 50% and 20% of patients, respectively, in the United States alone. Oxidative stress and glutathione depletion are implicated in APAP-induced liver necrosis. Boldine, a plant-derived compound is shown to have promising antioxidant potential. Therefore, this study investigates the protective effect of boldine against APAP-induced acute hepatic necrosis in mice. A single toxic dose of APAP (300 mg/kg b.w. p.o.) was administered in overnight-fasted mice to induce acute liver necrosis. Separately, APAP + boldine and APAP + N-acetylcysteine (NAC) simultaneous treatments were also given. Serum transaminases and reduced glutathione, enzymic antioxidants, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and, IL-6 were evaluated in liver tissue. Acute APAP intoxication significantly elevated serum marker enzymes of hepatotoxicity. APAP administration increased lipid peroxidation, TNF-α, IL-1ß, and IL-6 protein expressions. The enzymic antioxidants and reduced glutathione levels were decreased in liver tissue of APAP intoxicated mice. Boldine and NAC simultaneous treatments prevented APAP-induced oxidative stress, inflammation, and necrosis. The results of this study suggest the crucial role of boldine to protect against APAP induced hepatotoxicity by virtue of its antioxidant and anti-inflammatory properties.

Melatonin regulates tumor angiogenesis via miR-424-5p/VEGFA signaling pathway in osteosarcoma.

Melatonin is recognized as an anti-angiogenic agent, but its function in the tumor microenvironment especially in osteosarcoma remains uncertain. Among the selected miRNAs, miR-205, miR-424, miR-140, miR-106, and miR-519 were upregulated by melatonin in osteosarcoma cells. The functional role of miR-424-5p in osteosarcoma was further analyzed using miR-424-5p mimic/inhibitor. VEGFA mRNA and protein expression were altered by miR-424-5p mimic/inhibitor transfection with and without melatonin treatment and it was further identified that the VEGFA 3'UTR is directly targeted by miR-424-5p using the luciferase reporter gene system. The conditioned medium from SaOS2 and MG63 cells treated with melatonin and/or transfected with miR-424-5p mimic/inhibitor was exposed to endothelial cells, and cell proliferation and migration was analyzed. MG-63 and SaOS2 cells are also transfected with miR-424-5p inhibitors and positioned on CAM vascular bed to study the angiogenic activity at both morphological and molecular level under melatonin treatment. Our observations demonstrate for the first time that, melatonin upregulated the expression of miR-424-5p in osteosarcoma inhibiting VEGFA. Furthermore, it suppresses tumor angiogenesis, modulating surrounding endothelial cell proliferation and migration as well as the morphology of blood vessels, and angiogenic growth factors. These findings suggest that melatonin could play a pivotal role in tumor suppression via miR-424-5p/VEGFA axis.

Cytotoxic potentials of silibinin assisted silver nanoparticles on human colorectal HT-29 cancer cells.

It is of interest to study the cytotoxicity of silibinin assisted silver nanoparticles in human colorectal (HT-29) cancer cells. Silver nanoparticles were synthesized using silibinin as a reducing agent. The synthesized silibinin assisted silver nanoparticles ( SSNPs) were characterized and analyzed using a transmission electron microscope and spectrophotometer. The SSNPs synthesized in this study are spherical and their size ranges from 10 to 80 nm. HT-29 cells were treated with different concentrations (2, 4, 6, 8 and 10 ng/mL) of SSNPs and cytotoxicity was evaluated. The apoptosis was using flow cytometry. p53 protein expression using western blot. SSNPs are induced a decrease in viability and increased concentration-dependent cytotoxicity in HT-29 cells. SSNPs treatment also caused apoptosis-related morphological changes. SSNPs treatments at 8 and 16 ng/ml showed a prominent apoptotic change i.e., 70.3% and 83.6% respectively, and decreased viability of HT-29 cells 20% and 11.2% respectively as compared to control cells. SSNPs treatments induced p53 expression in HT-29 cells. Data shows that SSNPs have the potential to induce apoptosis in colorectal cancer cells. This provides insights for the further evaluation of SSNPs in fighting colon cancer.

Anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris.

Astaxanthin (AXN) is known to have health benefits by epidemiological studies. Therefore, it is of interest to assess the effect of AXN (derived from indigenous unicellular green alga Haematococcus lacustris) to modulate cell cycle arrest, lysosomal acidification and eventually apoptosis using in vitro in A549 lung cancer cells. Natural extracts of astaxanthin were obtained by standardized methods as reported earlier and characterized by standard HPLC and MS. Treatment of A549 cells with AXN (purified fraction) showed significant reduction in cell viability (about 50%) as compared to crude extract at 50µM concentration. Thus, we show the anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris for further consideration. Together, our results demonstrated the anticancer potential of AXN from Haematococcus lacustris, which is found to be mediated via its ability to induce cell cycle arrest, lysosomal acidification and apoptotic induction.

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.

In Vitro Anti-Neuroblastoma Activity of Thymoquinone Against Neuro-2a Cells via Cell-cycle Arrest.

We have recently shown that thymoquinone (TQ) has a potent cytotoxic effect and induces apoptosis via caspase-3 activation with down-regulation of XIAP in mouse neuroblastoma (Neuro-2a) cells. Interestingly, our results showed that TQ was significantly more cytotoxic towards Neuro-2a cells when compared with primary normal neuronal cells. In this study, the effects of TQ on cell-cycle regulation and the mechanisms that contribute to this effect were investigated using Neuro-2a cells. Cell-cycle analysis performed by flow cytometry revealed cell-cycle arrest at G2/M phase and a significant increase in the accumulation of TQ-treated cells at sub-G1 phase, indicating induction of apoptosis by the compound. Moreover, TQ increased the expression of p53, p21 mRNA and protein levels, whereas it decreased the protein expression of PCNA, cyclin B1 and Cdc2 in a dose- dependent manner. Our finding suggests that TQ could suppress cell growth and cell survival via arresting the cell-cycle in the G2/M phase and inducing apoptosis of neuroblastoma cells.

Thymoquinone inhibits cell proliferation through regulation of G1/S phase cell cycle transition in N-nitrosodiethylamine-induced experimental rat hepatocellular carcinoma.

Dysregulated cell proliferation and tumorigenesis is frequently encountered in several cancers including hepatocellular carcinogenesis (HCC). Thus, agents that inhibit cell proliferation and restrain hepatic tumorigenesis through cell cycle regulation have a beneficial effect in the treatment of hepatocellular carcinogenesis. The present study was aimed to investigate the efficacy of thymoquinone (TQ), an active compound derived from the medicinal plant Nigella sativa, on N-nitrosodiethylamine (NDEA) [0.01% in drinking water for 16 weeks]-induced hepatocarcinogenesis in experimental rats. After experimental period, the hepatic nodules, liver injury markers and tumor markers levels were substantially increased in NDEA induced liver tumors in rats. However, TQ (20mg/kg body weight) treatment greatly reduced liver injury markers and decreased tumor markers and prevented hepatic nodule formation and reduced tumor multiplicity in NDEA induced hepatic cancer bearing rats and this was evident from argyrophilic nucleolar organizer region (AgNORs) staining. Moreover, the uncontrolled cell proliferation was assessed by specific cell proliferative markers [proliferating cell nuclear antigen (PCNA) and Ki67] by immunofluorescence, immunoblot and analysis of mRNA expression. Simultaneously, we assessed the activity of TQ on G1/S phase cell cycle regulation with specific cell cycle proteins (p21(WAF1/CIP1), CDK4, Cyclin D1 and Cyclin E) by immunoprecipitation in experimental rats. Treatment with TQ significantly reduced the detrimental alterations by abrogating cell proliferation, which strongly induced G1/S arrest in cell cycle transition. In conclusion, our results suggest that TQ has a potent anti proliferative activity by regulating the G1/S phase cell cycle transition and exhibit a beneficial role in the treatment of HCC.

Geraniol modulates tongue and hepatic phase I and phase II conjugation activities and may contribute directly to the chemopreventive activity against experimental oral carcinogenesis.

Xenobiotic metabolizing enzymes are chief determinants in both the susceptibility to mutagenic effect of chemical carcinogens and in the response of tumors to chemotherapy. The present study was aimed to analyze the effect of geraniol administration on the activity of phase I and phase II carcinogen metabolizing enzymes through the nuclear factor erythroid 2-related factor-2 (Nrf2) activation against 4-niroquinoline-1-oxide (4NQO) induced oral carcinogenesis. The well-known chemical carcinogen 4NQO (50 ppm) was used to induce oral carcinogenesis through drinking water for 4, 12, and 20 weeks. The degree of cancer progression at each stage was confirmed by histological examination. At the end of the experimental period, 100% tumor formation was observed in the oral cavity of 4NQO induced animals with significant (P<0.05) alteration in the status of tumor markers, tongue and liver phase I and phase II drug metabolizing enzymes indicating progression of disease. Oral administration of geraniol at the dose of 200 mg/kg b.wt., thrice a week to 4NQO induced animals was able to inhibit tumor formation and thereby delayed the progression of oral carcinogenesis by modulating tongue and liver phase I and phase II drug metabolizing enzymes, as substantiated further by the histological and transmission electron microscopic studies. Our results demonstrate that geraniol exerts its chemopreventive potential by altering activities of phases I and II drug metabolizing enzymes to achieve minimum bioactivation of carcinogen and maximum detoxification.

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.

Anti-cancer effects of thymoquinone in mouse neuroblastoma (Neuro-2a) cells through caspase-3 activation with down-regulation of XIAP.

Thymoquinone (TQ) is a bioactive component derived from the medicinal plant Nigella sativa. Recent studies reported that TQ exhibited cytotoxic effects in several cancer cell lines. Currently, no information in the literature is found concerning its mechanisms and cytotoxicity on neuroblastoma cells. In this study, the cytotoxicity of TQ in mouse neuroblastoma cells (Neuro-2a) was investigated. Our results showed that TQ significantly reduced viability of Neuro-2a cells than normal neuronal cells. Apoptosis induction by TQ was confirmed by DAPI and AO/PI staining. TQ triggered the apoptotic pathway, which was characterized by increased Bax/Bcl-2 ratio. TQ significantly increased the expression of pro-apoptotic protein Bax, whereas decreased the expression of anti-apoptotic protein Bcl-2, which leads to the release of cytochrome c from mitochondria into the cytoplasm. Moreover, TQ treatment directs the activation of caspase-3 followed by the cleavage of poly(ADP-ribose) polymerase (PARP). Interestingly, we also observed that TQ down-regulated caspase inhibitor X-linked inhibitor of apoptosis protein (XIAP). These results indicate that TQ induces apoptosis via caspase-3 activation with down-regulation of XIAP in Neuro-2a cells.

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.

Potential preventive effect of carvacrol against diethylnitrosamine-induced hepatocellular carcinoma in rats.

Antioxidants are one of the key players in tumorigenesis, several natural and synthetic antioxidants were shown to have anticancer effects. The aim of the present study is to divulge the chemopreventive nature of carvacrol during diethylnitrosamine (DEN)-induced liver cancer in male wistar albino rats. Administration of DEN to rats resulted in increased relative liver weight and serum marker enzymes aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and gamma glutamyl transpeptidase (γGT). The levels of lipid peroxides elevated (in both serum and tissue) with subsequent decrease in the final body weight and tissue antioxidants like superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR). Carvacrol supplementation (15 mg/kg body weight) significantly attenuated these alterations, thereby showing potent anticancer effect in liver cancer. Histological observations and transmission electron microscopy studies were also carried out, which added supports to the chemopreventive action of the carvacrol against DEN-induction during liver cancer progression. These findings suggest that carvacrol prevents lipid peroxidation, hepatic cell damage, and protects the antioxidant system in DEN-induced hepatocellular carcinogenesis.