Carcinogen-induced early molecular events and its implication in the initiation of chemical hepatocarcinogenesis in rats: Chemopreventive role of vanadium on this process

Ameliorative effects of Turbinaria ornata extract on hepatocellular carcinoma induced by diethylnitrosamine in-vivo

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths and the fifth most common cancer worldwide. Brown algae appeared to be a rich source of efficient and safe agents against many life-threatening diseases like cancer. Thus, the scope of this study was to investigate the therapeutic effects of Turbinaria ornata against experimentally induced HCC in a rat model. Accordingly, forty male albino rats were divided into four groups. HCC was induced by intraperitoneal injection with diethylnitrosamine (DENA) followed by carbon tetrachloride (CCL4). After four weeks of DENA + CCL4 injection and two weeks of treatment with Turbinaria ornata, rats were sacrificed to collect hepatic tissue and blood samples for histopathological observations and various biochemical markers such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alpha-fetoprotein (AFP), urea, creatinine, albumin (ALB), and alkaline phosphatase (ALP). Rats that were injected for four weeks with DENA + CCL4 showed a significant increase in AFP levels, transforming growth factor-beta (TGF-β) and tumor necrosis factor-alpha (TNF-α), as well as a high percentage of malignant changes in hepatic tissues. The extension of malignant changes in the rat liver tissues was markedly reduced using Turbinaria ornata, as the treatment displayed liver patterns similar to that of the normal control rats. Furthermore, rats with HCC fed with Turbinaria ornata extract for two weeks showed decreasing levels of TGF-β and TNF-α. These findings demonstrate that Turbinaria ornata supplement can prevent HCC development in hepatic rats; however, the exact mechanism requires further investigation.

Bioguided isolation of potential antitumor agents from the aerial parts of cultivated cardoon (Cynara cardunculus var. altilis)

Hepatocellular carcinoma (HCC) is one of the leading causes of mortality worldwide; therefore, searching for an effective treatment for this illness is of great importance. In the present work, in vitro cytotoxic activity of the ethanol extract of the aerial parts of Cynara cardunculus L. against human liver carcinoma cells (Hep G2) was tested. Additionally, the antitumor activity of the extract was confirmed using chemically induced rat liver carcinogenesis with diethylnitrosamine (DEN). Moreover, bioguided fractionation and column chromatographic separation of the active compounds were carried out. The extract of C. cardunculus showed a promising cytotoxic activity according to the protocols of the National Cancer Institute. Bioguided chromatographic separation of the ethanol extract of C. cardunculus led to the isolation of seven secondary metabolites including two sesquiterpene lactones as the principal active components of the methylene chloride soluble fraction, grosheimin (IC50 = 7.49 µg/mL) and cynaropicrin (IC50 = 13.9 µg/mL). The compounds were characterized by different spectroscopic techniques such as EI-MS, IR and NMR. Additionally, in silico analysis of the two active compounds revealed their ability to bind with caspase-3 via hydrogen bonds interactions to initiate apoptosis of cancer cells. The results shed the light on the significance of C. cardunculus as a potential source of antitumor agents.

Protective effects of butylated hydroxytoluene on the initiation of N-nitrosodiethylamine-induced hepatocellular carcinoma in albino rats

Diethylnitrosamine (DEN), a hepatocarcinogen, is found in a variety of smoked and fried foods and was reported to be hepatotoxic in mice. Butylated hydroxytoluene (BHT) is a potent antioxidant used in cosmetic formulations and as a food additive and preservative. As a result, BHT was studied as a potential inhibitor in the early stages of diethylnitrosamine (DEN)-induced HCC. Male Wistar albino rats (n = 24) were equally subdivided. Group 1 was the negative control; Group 2 and 3 administered BHT and DEN, respectively; Group 4 received BHT followed by DEN. Blood samples and rat livers were taken for biochemical and histological investigation. Hepatotoxicity was assessed by increased liver enzymes and HCC indicators, along with reduced antioxidant and pro-apoptotic factors. AFP, AFPL3, GPC3, GSH, SOD, MDA, CASP3 and BAX expression increased significantly after DEN treatment. DEN also reduced GPx, CAT, and CYP2E1 activity, and BCl-2 expression. Moreover, in the hepatic parenchyma, the DEN caused histological alterations. Pretreatment with BHT enhanced antioxidant status while preventing histopathological and most biochemical alterations. BHT pretreatment suppresses DEN-initiated HCC by decreasing oxidative stress, triggering intrinsic mitotic apoptosis, and preventing histopathological changes in liver tissue.

Stability in solution and chemoprotection by octadecavanadates(IV/V) in E. coli cultures

Two mixed-valence octadecavanadates, (NH₄)₂(Me₄N)₅[V^IV₁₂V^V₆O₄₂I]·Me₄NI·5H₂O (V₁₈I) and [{K₆(OH₂)₁₂V^IV₁₁V^V₇O₄₁(PO₄)·4H₂O}_n] (V₁₈P), were synthesized and characterized by single-crystal X-ray diffraction analysis and FTIR, Raman, ⁵¹V NMR, EPR and UV/Vis/NIR spectroscopies. The chemoprotective activity of V₁₈I and V₁₈P towards the alkylating agent diethyl sulfate was assessed in E. coli cultures. The complex V₁₈I was nontoxic in concentrations up to 5.0 mmol L^-1, while V₁₈P presented moderate toxicity in the concentration range 0.10 - 10 mmol L^-1. Conversely, a ca. 35% enhancement in culture growth as compared to cells treated only with diethyl sulfate was observed upon addition of V₁₈I (0.10 to 2.5 mmol L^-1), while the combination of diethyl sulfate with V₁₈P increased the cytotoxicity presented by diethyl sulfate alone. ⁵¹V NMR and EPR speciation studies showed that V₁₈I is stable in solution, while V₁₈P suffers partial breakage to give low nuclearity oxidometalates of vanadium(V) and (IV). According to the results, the chemoprotective effect depends strongly on the direct reactivity of the polyoxidovanadates (POV) towards the alkylating agent. The reaction of diethyl sulfate with V₁₈I apparently produces a new, rearranged POV instead of poorly-reactive breakage products, while V₁₈P shows the formation and subsequent consumption of low-nuclearity species. The correlation of this chemistry with that of other mixed-valence polyoxidovanadates, [H₆V^IV₂V^V₁₂O₃₈PO₄]^5- (V₁₄) and [V^IV₈V^V₇O₃₆Cl]^6- (V₁₅), suggests a relationship between stability in solution and chemoprotective performance.

Inhibitory and ameliorative effect of heliomycin derived from actinomycete on induced hepatocellular carcinoma in rats

The hepatoprotective activity of heliomycin obtained from the culture broth of actinomycete AB5 against diethylnitrosamine (DEN)-induced hepatic cancer in Wistar rats was estimated. Heliomycin exhibited a significant decrease in the levels of alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) compared to the positive control. For instance, the heliomycin group after 20 weeks showed a significant decline in ALT, AST, and ALP values (70.75 ± 5.12, 140.25 ± 11.75, and 163.25 ± 18.66, respectively) compared to the positive control group (170.00 ± 9.55, 252.75 ± 12.33, and 278.00 ± 21.32, respectively). Additionally, the isolated compound showed a highly significant decrease in serum alpha-fetoprotein (AFP) levels. After 8, 16, and 20 weeks, the mean values of AFP in the heliomycin group revealed a highly significant decrease (33.62 ± 2.46, 30.00 ± 4.05, and 28.50 ± 2.64, respectively) compared to the positive control group (49.45 ± 3.03, 81.90 ± 6.70, and 90.75 ± 5.12, respectively). The histopathological investigation of liver sections supported the results of biochemical analysis. It was demonstrated that heliomycin showed histological improvement of hepatocytes and marked increase of nuclear pyknotic with clear cytoplasm, which is a sign of improving the apoptotic pathway of malignant cells. It also displayed marked fibrosis at most of the malignant cells and the development of some regenerative nodules. Heliomycin showed moderate immunoreactivity with alpha-fetoprotein (AFP), and proliferation cell nuclear antigen (PCNA) compared to the positive control group. To the best of our knowledge, this is the first study to report the anticancer activity of heliomycin against hepatocellular carcinoma in vivo.

Effect of co-administration of Bee honey and some chemotherapeutic drugs on dissemination of hepatocellular carcinoma in rats

Alternative and complimentary usage of the natural compound has raised hopes of finding curative options for liver hepatocarcinogenesis. In the present study, the curative effect of bee honey against diethylnitrosamine (DEN) (50 mg/kg) and carbon tetrachloride (CCl4) (2 mg/Kg)-induced hepatocellular carcinoma (HCC) in male rats in the presence or absence of some chemotherapeutic drugs, Cisplatin (Cis), Cyclophosphamide (CY) and 5- Fluorouracil (5-FU) were investigated. The obtained results demonstrated that treatment with DEN/CCl4 caused oxidative stress as assigned by the increase in malondialdehyde (MDA) and fall in glutathione (GSH) content. Meantime detraction in the antioxidants, including superoxide dismutase (SOD), catalase (CAT), glutathione-s-transferase (GST) and glutathione peroxidase (GPx) was observed. Also, the results showed induction of inflammation as reflected by an increase in the levels of both α- fetoprotein and α- fucosidase in the liver. This was accompanied by changes in the hepatic function biomarkers which characterized by the increased levels of transaminases (AST, ALT), alkaline phosphatase (ALP) and γ-Glutamyl transferase (γ-GT) and decrease in total protein content in the serum. In conclusion, the combination of the selected drugs and bee honey may be an effective chemo- preventive and therapeutic strategy for treating DEN and CCl4-induced HCC.

The potential chemo preventive effect of ursolic acid isolated from Paulownia tomentosa, against N-diethylnitrosamine: initiated and promoted hepatocarcinogenesis

The present study discusses the isolation of ursolic acid from the chloroform extract of Paulownia tomentosa (Thunb) Steud fruits and its cytotoxic effect has been assessed in-vitro was performed in different cells lines (A-549, MCF-7, HepG2) and in-vivo using N-diethylnitrosamine. The obtained results revealed that ursolic acid showed significant cytotoxic activity on MCF-7 and HepG2 cell lines in comparison to Doxorubicin as a reference drug. Moreover, we have assessed the inhibitory effects of Paulownia tomentosa fruit chloroform extract and the isolated ursolic acid on hepatocarcinogenesis was carried out for the first time using N-diethylnitrosamine, where the group treated with ursolic acid given orally after 8 weeks of cancer induction showed the most significant results in comparison to the chloroform extract. The effect of ursolic acid on intoxicated rats caused significant restoration of most of the normal hepatocytes architecture with regular dark nuclei and the group treated with Paulownia tomentosa fruits showed remarkable results with improvement in biochemical analysis.

Preventive effects of combinative natural foods produced by elite crop varieties rich in anticancer effects on N-nitrosodiethylamine-induced hepatocellular carcinoma in rats

The World Cancer Research Fund International has released 32 anticancer effects (ACEs) that targeted every stage of cancer processes. Thus, we designed two formulas of natural food combination Diet I and Diet II, mainly produced by elite crop varieties rich in ACEs with different mixture ratios, and evaluated their cancer preventive effects on N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. After 20 weeks of dietary intervention, Diet I and Diet II reduced incidence, size, and number of hepatic nodules (p < 0.01) and prevented hepatic tumor formation in NDEA-induced hepatocarcinogenesis rats. Low-grade hepatic dysplasia incidence was 20% for Diet II and 40% for Diet I, and apparent hepatocellular carcinomas (HCC) rates were both 0, while 90% HCC in control diet treatment group (p < 0.01). Diet I and Diet II ameliorated abnormal liver function enzymes, reduced serum alpha fetal protein, tumor-specific growth factor, dickkopf-related protein 1, tumor necrosis factor-alpha and interleukin-6 levels, regulated hepatic phase I and II xenobiotic-metabolizing enzymes, enhanced antioxidant capacity, suppressed NDEA-initiated oxidative DNA damage, and induced apoptosis coupled to down-regulation of proinflammatory, invasion, and angiogenesis markers. Daily intake of combination diet produced from ACEs-rich elite crop varieties can effectively prevent or delay occurrence and development of NDEA-induced hepatocarcinogenesis in rats.

Biochemical Evidence for the Antitumor Potential of Garcinia mangostana Linn. On Diethylnitrosamine-Induced Hepatic Carcinoma

Background

Garcinia mangostana is extensively used in most of the Indian herbal pharmaceuticals and nutraceuticals.

Objective

The objective of this study was to elucidate the underlying biochemical protective mechanism of G. Mangostana Linn. fruit extract (GME) in deterioration of diethylnitrosamine (DEN)-induced hepatic carcinoma (HCC) in rats.

Materials and Methods

The cancer was induced using DEN to the experimental rats and treated with GME (200, 400, and 600 mg/kg) to find its anticancer property. The cancer biomarkers such as alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), hepatic hydroxyl proline, total tissue protein, and tumor necrosis factor-alpha levels were measured using ELISA. The vascular endothelial growth factor expressions were also seen in liver tissues using immunohistochemistry.

Results

In addition, there was a significant increase in serum AFP, CEA, hepatic hydroxylproline, and total tissue protein levels in HCC group versus the negative control group. In contrast, the groups with HCC subjected to either high or low dose of GME elicited significant reduction of AFP, CEA, hepatic hydroxylproline, and increase in total protein in serum compared to the untreated HCC rats. Interestingly, treatment with GME elicited marked improvement in the liver histological feature and downregulation of tumor necrosis factor-alpha levels in HCC groups. GME extract may have chemopreventive benefits by reducing the tumor promoting growth factor levels in HCC-induced group.

Conclusion

To sum up, all findings on curative groups had proved clearly that the GME has anticarcinogenic effect on the development of liver cancer induced by DEN in rats.

SUMMARY

Garcinia mangostana Linn. (GME) may have chemopreventive property by reducing the tumor promoting growth factor and tumor necrosis factor-alpha levels in diethylnitrosamine (DEN)-induced hepatic cancerThe suppression in the levels of cancer biomarkers by GME due to the presence of anticancer phytoconstituentsThe histological studies proved the effective dose of GME against DEN-induced experimental hepatic cancer. Abbreviations used: TNF-α: Tumor necrosis factor-alpha, PBS: Phosphate buffered saline, ROS: Reactive oxygen species, DNA: Deoxyribonucleic acid, GSH: Glutathione, VEGF: Vascular endothelial growth factor.

Immunohistochemical, histopathological study and chemoprotective effect of Solanum nigrum in N-nitrosodiethylamine-induced hepatocellular carcinoma in Wistar rats

Background and Aim

Cancer is a devastating disease with a severe impact on the physical and psychological well-being of patients. Hepatocellular carcinoma (HCC) has been reported in various species of animals including dogs, cats, sheep, and pigs. The present study aimed to study the immunohistochemical and histopathological changes andchemoprotective effect of aqueous and alcoholic extracts of Solanum nigrum on N-nitrosodiethylamine (NDEA)-induced HCC rat model.

Materials and Methods

Eighty-two male Wistar rats of 15 weeks of age weighing 200-250 g were selected for the experiment. They were randomly divided into ten groups. Group I served as normal control consisted of healthy rats. HCC was induced in Group II, IV, V, VI, VII, and X rats using NDEA as inducing agent followed by phenobarbitone as a promoter for 16 weeks. Group II rats were kept untreated as HCC control. Group III rats were kept as vehicle control (0.05% Sodium bicarbonate). Group IV and V rats were treated with aqueous extract of S. nigrum at 200 mg/kg and 400 mg/kg, respectively, and Group VI and VII rats were treated with an alcoholic extract of S. nigrum at 200 mg/kg and 400 mg/kg, respectively, daily orally for 28 days. Group X rats were treated withsorafenib as reference drug at a dose of 11.4 mg/kg daily orally for 28 days. Group VIII and IX rats were kept as aqueous and alcoholic extract control for studying the effect of the same on normal rats. Liver samples were collected to study the gross and histopathological lesions and the activity of cleaved caspase-3 and chemopreventive effect of aqueous and alcoholic extracts of S. nigrum on HCC.

Results

The liver sections of rats from HCC control (Group II) showed loss of lobular architecture, necrosis, fatty change, enlarged and darkened nuclei with variable size, dilatation of hepatic sinusoids with Kupffer cell hyperplasia, dilatation and proliferation of bile duct, and intranuclear vacuoles and also showed the presence of more than one nucleolus. Administration of alcoholic extract of S. nigrum and sorafenib to NDEA/phenobarbital-treated rats reduced the severity of lesions in the liver. Immunohistochemical analysis of liver sections for caspase-3-positive cells of hepatic cancer-induced group showed immunoreactivity to rarely few. The immunoreactivity of the hepatocytes treated with a higher dose of alcoholic extract of S. nigrum was limited and was comparable to a standard drug, sorafenib.

Conclusion

Oral administration of aqueous and alcoholic extracts of S. nigrum for 28 days showed significant rejuvenation in the structure of the liver in the histopathological section in a dose-dependent manner in rats.

Vanadium Compounds as PTP Inhibitors

Phosphotyrosine signaling is regulated by the opposing actions of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Here we discuss the potential of vanadium derivatives as PTP enzyme inhibitors and metallotherapeutics. We describe how vanadate in the V oxidized state is thought to inhibit PTPs, thus acting as a pan-inhibitor of this enzyme superfamily. We discuss recent developments in the biological and biochemical actions of more complex vanadium derivatives, including decavanadate and in particular the growing number of oxidovanadium compounds with organic ligands. Pre-clinical studies involving these compounds are discussed in the anti-diabetic and anti-cancer contexts. Although in many cases PTP inhibition has been implicated, it is also clear that many such compounds have further biochemical effects in cells. There also remain concerns surrounding off-target toxicities and long-term use of vanadium compounds in vivo in humans, hindering their progress through clinical trials. Despite these current misgivings, interest in these chemicals continues and many believe they could still have therapeutic potential. If so, we argue that this field would benefit from greater focus on improving the delivery and tissue targeting of vanadium compounds in order to minimize off-target toxicities. This may then harness their full therapeutic potential.

Therapeutic role of a synthesized calcium phosphate nanocomposite material on hepatocarcinogenesis in rats

Nanotechnology research is booming worldwide, and the general belief is that medical and biological applications will form the greatest sector of expansion over the next decade. With this in mind, this study was designed to evaluate the therapeutic effects of a synthesized tricalcium phosphate nanocomposite material (nano-TCP) on hepatocarcinoma in a rat model, as initiated with diethylnitrosamine (DEN) and promoted with phenobarbital (PB). Hepatocarcinoma was induced with intraperitoneal injections of DEN (50 mg·(kg body mass)(-1)) 3 times a week for 2 weeks. Three weeks after the last dose of DEN, the rats received PB (0.05 %, w/v) in their drinking water for a further 6 weeks. Nano-TCP (100 mg·(kg body mass)(-1)) was administered intraperitoneally 3 times per week to rats with HCC. At the end of the experimental period, liver samples were collected from all animals for biochemical and histopathological analysis. The degree of DNA fragmentation was analyzed, in addition to immune status, by measuring the levels of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and interleukin-2 (IL-2). The activities of the most important free-radical scavengers of the antioxidant defense system as well as malondialdehyde (MDA) content and liver enzymes were measured. The levels of hepatic heat shock protein-70 (HSP-70), caspase-3, and metalloproteinase-9 were also measured as markers for inflammation and apoptosis. Histopathological examination of liver tissue was performed. The results revealed the potent efficacy of nano-TCP in repairing the fragmented DNA and ameliorating most of the investigated parameters by significant elevation in the levels of hepatic alanine aminotransferase (ALT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities. On the other hand, there was a significant decrease in hepatic gamma-glutamyl transpeptidase (γ-GT), MDA, IL-2, IFN-γ, TNF-α, matrix metalloproteinase-9 (MMP-9), HSP-70, and caspase-3 levels upon treatment. The findings form histopathological examination of the liver tissues agreed with the biochemical results and confirmed the difference between the control and treatment groups. In conclusion, nano-TCP succeeded in treating hepatocarcinoma efficiently, and presents a new hope for patients to get safe, fast, and effective treatment.

Significance of Rumex vesicarius as anticancer remedy against hepatocellular carcinoma: a proposal-based on experimental animal studies

Rumex vesicarius is an edible herb distributed in Egypt and Saudi Arabia. The whole plant has significant value in folk medicine and it has been used to alleviate several diseases. Hepatocellular carcinoma (HCC), the major primary malignant tumor of the liver, is one of the most life-threatening human cancers. The goal of the current study was to explore the potent role of Rumex vesicarius extract against HCC induced in rats. Thirty adult male albino rats were divided into 3 groups: (I): Healthy animals received orally 0.9% normal saline and served as negative control group, (II): HCC group in which rats were orally administered N-nitrosodiethylamine NDEA, (III): HCC group treated orally with R. vesicarius extract in a dose of 400 mg/kg b.wt daily for two months. ALT and AST, ALP and γ-GT activities were estimated. CEA, AFP, AFU, GPC-3, Gp-73 and VEGF levels were quantified. Histopathological examination of liver tissue sections was also carried out. The results of the current study showed that the treatment of the HCC group with R. vesicarius extract reversed the significant increase in liver enzymes activity, CEA, AFP, AFU, glypican 3, golgi 73 and VEGF levels in serum as compared to HCC-untreated counterparts. In addition, the favorable impact of R. vesicarius treatment was evidenced by the marked improvement in the histopathological features of the liver of the treated group. In conclusion, the present experimental setting provided evidence for the significance of R. vesicarius as anticancer candidate with a promising anticancer potential against HCC. The powerful hepatoprotective properties, the potent antiangiogenic activity and the effective antiproliferative capacity are responsible for the anticancer effect of this plant.

Chemoprotective activity of mixed valence polyoxovanadates against diethylsulphate in E. coli cultures: insights from solution speciation studies

Cell survival after treatment with dimethylsulphate in the presence of polyoxovanadates.

Mammalian models of chemically induced primary malignancies exploitable for imaging-based preclinical theragnostic research

Compared with transplanted tumor models or genetically engineered cancer models, chemically induced primary malignancies in experimental animals can mimic the clinical cancer progress from the early stage on. Cancer caused by chemical carcinogens generally develops through three phases namely initiation, promotion and progression. Based on different mechanisms, chemical carcinogens can be divided into genotoxic and non-genotoxic ones, or complete and incomplete ones, usually with an organ-specific property. Chemical carcinogens can be classified upon their origins such as environmental pollutants, cooked meat derived carcinogens, N-nitroso compounds, food additives, antineoplastic agents, naturally occurring substances and synthetic carcinogens, etc. Carcinogen-induced models of primary cancers can be used to evaluate the diagnostic/therapeutic effects of candidate drugs, investigate the biological influential factors, explore preventive measures for carcinogenicity, and better understand molecular mechanisms involved in tumor initiation, promotion and progression. Among commonly adopted cancer models, chemically induced primary malignancies in mammals have several advantages including the easy procedures, fruitful tumor generation and high analogy to clinical human primary cancers. However, in addition to the time-consuming process, the major drawback of chemical carcinogenesis for translational research is the difficulty in noninvasive tumor burden assessment in small animals. Like human cancers, tumors occur unpredictably also among animals in terms of timing, location and the number of lesions. Thanks to the availability of magnetic resonance imaging (MRI) with various advantages such as ionizing-free scanning, superb soft tissue contrast, multi-parametric information, and utility of diverse contrast agents, now a workable solution to this bottleneck problem is to apply MRI for noninvasive detection, diagnosis and therapeutic monitoring on those otherwise uncontrollable animal models with primary cancers. Moreover, it is foreseeable that the combined use of chemically induced primary cancer models and molecular imaging techniques may help to develop new anticancer diagnostics and therapeutics.

Curcumin ameliorate DENA-induced HCC via modulating TGF-β, AKT, and caspase-3 expression in experimental rat model

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. In laboratory animal models, diethylnitrosamine (DENA) is a well-known agent that has a potent hepatocarcinogenic effect that is used to induce HCC. As curcumin has a potent anti-inflammatory effect with strong therapeutic potential against a variety of cancers, our present study aims to investigate its curative effects and the possible mechanisms of action against DENA-induced HCC in male rats. Investigation of biochemical and molecular parameters of HCC animal model liver showed an overexpression of TGF-β and Akt proteins accompanied with a significant reduction of the proapoptotic marker caspase-3. DENA-induced hepatic cellular injury resulted also in a significant increase in liver function marker enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lipid peroxides in this group. Curcumin treatment partially reversed DENA-induced damage as it reduced the overexpression of the angiogenic and anti-apoptotic factors TGF-β and Akt and improved caspase-3 expression. Also, it could partially normalize the serum values of liver marker enzymes and lipid peroxidation and improve liver architecture. Curcumin shows a unique chemotherapeutic effect in reversing DENA-induced HCC in rat model. This effect is possibly mediated through its proapoptotic, antioxidant, anti-angiogenic, as well as antimitotic effects. It interferes and modulates cell signaling pathways and hence turns death signals and apoptosis on within tumor cells.

Anticancer potential of rhamnocitrin 4'-β-D-galactopyranoside against N-diethylnitrosamine-induced hepatocellular carcinoma in rats

The hepatoprotective activity of flavonoid rhamnocitrin 4'-β-D-galactopyranoside (RGP) obtained from leaves of Astragalus hamosus L. against N-diethylnitrosamine (DENA)-induced hepatic cancer in Wistar albino rats was evaluated. Hepatic cancer in rats was induced by single-dose intraperitoneal administration of DENA (200 mg/kg). Induction of hepatic cancer was confirmed after 7 days of DENA administration by measurement of elevated level of serum α-feto protein (AFP). Administration of DENA in a single dose lofted the levels of serum biochemical parameters like alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, total protein and AFP. Antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and lipid per oxidation (LPO) were annealed significantly by administration of RGP in a dose-dependant manner. The histopathological examination of rat liver section was found to reinforce the biochemical observations significantly. It was observed that a substantial and dose-dependent reversal of DENA-diminished activity of antioxidant enzymes like SOD, CAT, GPx, GST and the reduced DENA-elevated level of LPO with a marked change. Any elevation in the levels of serum markers along with suppression of free radical formation by scavenging the hydroxyl radicals is significantly prevented by RGP. It also modulates the levels of LPO and perceptibly increases the endogenous antioxidant enzymes level in DENA-induced hepatocellular carcinogenesis. The findings suggest that RGP prevents hepatocellular carcinoma by suppressing the marked increase in the levels of serum marker enzymes, and suppresses the free radical by scavenging hydroxyl radicals.

Potential chemoprevention of diethylnitrosamine-induced hepatocarcinogenesis in rats: myrrh (Commiphora molmol) vs. turmeric (Curcuma longa)

The aim of the present study was to assess the potential chemopreventive effects of myrrh (Commiphora molmol) vs. turmeric (Curcuma longa) in hepatocarcinogenic rats induced by a single intraperitoneal injection of diethylnitrosamine (DENA) (200 mg/kg body weight). Ninety male Wistar rats used in this study were randomly divided into six equal groups (n=15). Group 1 rats served as negative controls; group 2 received a single i.p. injection of DENA and served as positive controls. Rats in both groups were fed on basal diet. Group 3 rats were fed a diet containing 5% turmeric, whereas group 4 rats were fed a diet containing 2% myrrh. Rats in groups 5 and 6 received a single i.p. injection of DENA and were fed diets containing 5% turmeric and 2% myrrh, respectively. The study demonstrated that DENA caused a significant increase in serum indices of liver enzymes and also severe histological and immunohistochemical changes in hepatic tissues. These included disorganized hepatic parenchyma, appearance of pseudoacinar and trabecular arrays of hepatocytes and alterations in CD10-immunoreactivity. Dietary supplementation of turmeric relatively improved the biochemical parameters to values approximating those of the negative controls and delayed the initiation of carcinogenesis. In contrast, myrrh did not improve the biochemical parameters or delay the hepatocarcinogenesis. Both turmeric and myrrh induced significant biochemical and histological changes in non-treated rats. In conclusion, DENA significantly changes the biological enzymatic activities in serum and the integrity of hepatic tissues. Phytochemicals with potential hepatoprotective effects must be applied cautiously owing to their potential hepatotoxicity.

Spectroscopic characterization of lycopene extract from Lycopersicum esculentum (Tomato) and its evaluation as a chemopreventive agent against experimental hepatocarcinogenesis in mice

The present study was designed to characterize the lycopene extract (LycT) prepared from tomatoes (Lycopersicum esculentum) and then to evaluate its chemopreventive efficacy in N-diethylnitrosamine (NDEA)-induced experimental hepatocarcinogenesis in female Balb/c mice. The extraction of lycopene was carried out using hexane/acetone/ethanol as an extracting medium and then characterized by ultraviolet-visible, nuclear magnetic resonance and Fourier transform infrared spectroscopy. Chemopreventive efficacy of characterized LycT in vivo was evaluated in terms of hepatic tumour incidence, multiplicity, burden, hepatosomatic index and animal survival rate. Results indicated that average lycopene content of the tomato was 11.6-14 mg/kg tomato weight. Spectroscopic data confirmed the structural characteristics of lycopene in the extract. In the animal study, reduction in tumour incidence (42.05%), tumour burden (1.39) and tumour multiplicity (3.42) was observed upon LycT pretreatment to NDEA-treated animals. Histopathological analysis unravelled that the increased survival rate in LycT + NDEA-treated animals was due to the delay in the formation of aggressive tumour nodules. These observations indicate that lycopene seems to be an able candidate for chemoprevention in hepatocarcinogenesis resulting from NDEA insults.

Influence of vanadium supplementation on oxidative stress factors in the muscle of STZ-diabetic rats

In recent years, the role of free radical damage consequent to oxidative stress is widely discussed in diabetic complications. In this aspect, the protection of cell integrity by trace elements is a topic to be investigated. Vanadium is a trace element believed to be important for normal cell function and development. The aim of the present study was to investigate the effect of vanadyl sulfate supplementation on the antioxidant system in the muscle tissue of diabetic rats. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight) to male Swiss albino rats. The rats were randomly divided into 4 groups: Group I, control; Group II, vanadyl sulfate control; Group III, STZ-diabetic untreated; Group IV, STZ-diabetic treated with vanadyl sulfate. Vanadyl sulfate (100 mg/kg) was given daily by gavage for 60 days. At the last day of the experiment, rats were killed, muscle tissues were taken, homogenized in cold saline to make a 10% (w/v) homogenate. Body weights and blood glucose levels were estimated at 0, 30 and 60th days. Antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione-S-transferase (GST), as well as carbonic anhydrase (CA), myeloperoxidase (MPO) activities and protein carbonyl content (PCC) were determined in muscle tissue. Vanadyl sulfate administration improved the loss in body weight due to STZ-induced diabetes and decreased the rise in blood glucose levels. It was shown that vanadium supplementation to diabetic rats significantly decrease serum antioxidant enzyme levels, which were significantly raised by diabetes in muscle tissue showing that this trace element could be used as preventive for diabetic complications.

Vanadium in the detection, prevention and treatment of cancer: the in vivo evidence

Vanadium, a dietary micronutrient, is yet to be established as an essential part of the human diet. Over the past century, several biological effects of vanadium, such as insulin-mimetic action as well as amelioration of hyperlipidemia and hypertension, have been discovered. This transition element is known to influence a battery of enzymatic systems, namely phosphatases, ATPases, peroxidases, ribonucleases, protein kinases and oxidoreductases. Multiple biochemical and molecular actions of vanadium have been implicated in its inhibitory effects on various tumor cells of human origin. Successful in vitro studies over the past few decades have advanced the anticancer research on vanadium into the preclinical stage. Vanadium in several animal cancer models provides protection against all stages of carcinogenesis--initiation, promotion, and progression. This review focuses on the current advances in cancer prevention and treatment as well as early detection by vanadium compounds in preclinical animal models while pointing to possible mechanisms of such diverse beneficial effects. Clinical pharmacokinetic and potential toxicity studies on vanadium are also highlighted in this review. Supporting and challenging evidence as well as future directions of vanadium research exploring the possibility of using this dietary agent for detection, prevention and treatment of human cancers are critically discussed.

A comparison of the effects of three GM corn varieties on mammalian health

We present for the first time a comparative analysis of blood and organ system data from trials with rats fed three main commercialized genetically modified (GM) maize (NK 603, MON 810, MON 863), which are present in food and feed in the world. NK 603 has been modified to be tolerant to the broad spectrum herbicide Roundup and thus contains residues of this formulation. MON 810 and MON 863 are engineered to synthesize two different Bt toxins used as insecticides. Approximately 60 different biochemical parameters were classified per organ and measured in serum and urine after 5 and 14 weeks of feeding. GM maize-fed rats were compared first to their respective isogenic or parental non-GM equivalent control groups. This was followed by comparison to six reference groups, which had consumed various other non-GM maize varieties. We applied nonparametric methods, including multiple pairwise comparisons with a False Discovery Rate approach. Principal Component Analysis allowed the investigation of scattering of different factors (sex, weeks of feeding, diet, dose and group). Our analysis clearly reveals for the 3 GMOs new side effects linked with GM maize consumption, which were sex- and often dose-dependent. Effects were mostly associated with the kidney and liver, the dietary detoxifying organs, although different between the 3 GMOs. Other effects were also noticed in the heart, adrenal glands, spleen and haematopoietic system. We conclude that these data highlight signs of hepatorenal toxicity, possibly due to the new pesticides specific to each GM corn. In addition, unintended direct or indirect metabolic consequences of the genetic modification cannot be excluded.

Hepatoprotective and anti-hepatocarcinogenic effects of glycyrrhizin and matrine

Matrine (Mat), a component extracted from Sophora flavescens Ait, has a wide spectrum of pharmacological effects. Glycyrrhizin (Gly), a major active constituent of licorice (Glycyrrhiza glabra) root, has various pharmacological effects. Gly and Mat are ancillary drugs used clinically in China for protection of liver function and treatment of tumors. However, habitual administration of Gly may cause adverse effects marked by the development of pseudohypercorticosteroidism. This work was designed to see whether combination use of Gly and Mat could offer better liver protective and anti-hepatocarcinogenic effects than Gly or Mat alone, and whether it could reduce the adverse effects of Gly alone by acetaminophen-induced hepatotoxicity, diethylnitrosamine-induced hepatocarcinogenesis, induction of immunosuppression, albumen-induced swelling of rat hind paws. The results showed that compared with Gly or Mat alone, Gly+Mat reduced the mortality of acetaminophen overdosed mice more effectively, attenuate acetaminophen-induced hepatotoxicity, and reduced the number and area of gamma-GT positive foci, thus protecting liver function and preventing HCC from occurring. In addition, Gly+Mat had a protective effect on immunosuppression, a strong non-specific anti-inflammatory effect, and an effect of reducing the incidence of sodium and water retention.