Serum antioxidative vitamin levels and lipid peroxidation in gastric carcinoma patients

Chronic Gastric Ulcer Healing Actions of the Aqueous Extracts of Staple Plant Foods of the North-West, Adamawa, and West Regions of Cameroon

Aim

This study is aimed at establishing phenolic compound profile and assessing the possible antiulcer activities of aqueous extracts of some staple plant foods from the West and North-West regions of Cameroon against chronic gastric ulcer models in rats.

Materials and Methods

Phenolic constituents of extracts were evaluated using HPLC-DAD. Aqueous extracts of Corchorus olitorius, Solanum nigrum, Vigna unguiculata, Triumfetta pentandra, "nkui" spices, and "yellow soup" spices were tested at two doses (200 and 400 mg/kg). After treatments, animals were sacrificed, healing percentage and antioxidant status (catalase, superoxide dismutase, and glutathione peroxidase) were evaluated, and histological examination of gastric mucosa was realized.

Results

HPLC-DAD revealed that p-hydroxybenzoic and protocatechuic acids were the phenolic compound present in all extracts. Oral administration of extracts (200 and 400 mg/kg) significantly reduced ulcer surface value and significantly increased mucus production compared to the control groups (p < 0.05). Histological study supported the observed healing activity of different extracts characterized by a reduced inflammatory response. Moreover, administration of aqueous extracts increased the activity of antioxidant enzymes.

Conclusion

This study revealed that aqueous extracts of Solanum nigrum, Corchorus olitorius, Vigna unguiculata, Triumfetta pentandra, "yellow soup" spices, and "nkui" spices possess healing antiulcer effects against models of gastric ulcers. The antiulcer mechanisms involved may include increase of gastric mucus production and improvement of the antioxidant activity of gastric tissue. These activities may be due to the phenolic compounds identified in the extracts, especially p-hydroxybenzoic and protocatechuic acids present in all extracts and with known antioxidant, cytoprotective, and healing properties. However, all the diets may promote the healing process of chronic ulcers caused by excessive alcohol consumption/stress.

Role of Vitamin C in Selected Malignant Neoplasms in Women

Since the first reports describing the anti-cancer properties of vitamin C published several decades ago, its actual effectiveness in fighting cancer has been under investigation and widely discussed. Some scientific reports indicate that vitamin C in high concentrations can contribute to effective and selective destruction of cancer cells. Furthermore, preclinical and clinical studies have shown that relatively high doses of vitamin C administered intravenously in ‘pharmacological concentrations’ may not only be well-tolerated, but significantly improve patients’ quality of life. This seems to be particularly important, especially for terminal cancer patients. However, the relatively high frequency of vitamin C use by cancer patients means that the potential clinical benefits may not be obvious. For this reason, in this review article, we focus on the articles published mainly in the last two decades, describing possible beneficial effects of vitamin C in preventing and treating selected malignant neoplasms in women, including breast, cervical, endometrial, and ovarian cancer. According to the reviewed studies, vitamin C use may contribute to an improvement of the overall quality of life of patients, among others, by reducing chemotherapy-related side effects. Nevertheless, new clinical trials are needed to collect stronger evidence of the role of this nutrient in supportive cancer treatment.

Eremomastax speciosa (Hochst.) Cufod. counteracts the delaying effect of indomethacin on Helicobacter pylori-associated chronic gastric ulcers healing

ETHNOPHARMACOLOGICAL RELEVANCE

Information collected from local traditional healers reported that Eremomastax speciosa (Hochst.) Cufod. has for a long time been used to manage gastric ulcers in many regions of Cameroon and beyond. This traditional use is supported by numerous studies. However, efficacy of this plant has never been tested in case of chronic gastric ulcers associating Helicobacter pylori infection.

AIM OF THE STUDY

This study was designed to investigate curative effects of the aqueous extract of E. speciosa leaves (AEESL) against chronic gastric ulcers associated to Helicobacter pylori infection.

MATERIALS AND METHODS

Two experimental methods of chronic gastric ulcers, involving H. pylori infection, were performed using Wistar rats, namely: acetic acid-induced ulcers and "unhealed ulcers". E. speciosa extract was tested at three doses (100; 200; 400 mg/kg) and at the end of experiments, some in vivo antioxidant parameters were measured, bacterial load in stomach tissue calculated and histopathological examinations performed.

RESULTS

E. speciosa reduced ulcer index at all the doses and significantly increased mucus production as well as antioxidant (mainly SOD and GSH) level. Bacterial load in stomach significantly decreased (p < 0.05) in extract-treated groups (200 and 400 mg/kg) as confirmed by histopathological observations. The extract was found to be non toxic to healthy and cancerous cells (IC₅₀ > 1000 μg/mL).

CONCLUSIONS

E. speciosa accelerated healing of gastric ulcers even in presence of indomethacin, while decreasing bacterial loads in rats' stomachs. These results provide supplementary support to the use of E. speciosa in ethnomedicine and open new perspectives regarding development of a herbal-based monotherapy able to efficiently replace/supplement standard antiulcer tri/quadritherapy.

Vitamin C Transporters and Their Implications in Carcinogenesis

Vitamin C is implicated in various bodily functions due to its unique properties in redox homeostasis. Moreover, vitamin C also plays a great role in restoring the activity of 2-oxoglutarate and Fe²⁺ dependent dioxygenases (2-OGDD), which are involved in active DNA demethylation (TET proteins), the demethylation of histones, and hypoxia processes. Therefore, vitamin C may be engaged in the regulation of gene expression or in a hypoxic state. Hence, vitamin C has acquired great interest for its plausible effects on cancer treatment. Since its conceptualization, the role of vitamin C in cancer therapy has been a controversial and disputed issue. Vitamin C is transferred to the cells with sodium dependent transporters (SVCTs) and glucose transporters (GLUT). However, it is unknown whether the impaired function of these transporters may lead to carcinogenesis and tumor progression. Notably, previous studies have identified SVCTs’ polymorphisms or their altered expression in some types of cancer. This review discusses the potential effects of vitamin C and the impaired SVCT function in cancers. The variations in vitamin C transporter genes may regulate the active transport of vitamin C, and therefore have an impact on cancer risk, but further studies are needed to thoroughly elucidate their involvement in cancer biology.

A Nested Case-Control Study on Plasma Vitamin E and Risk of Cancer: Evidence of Effect Modification by Selenium

BACKGROUND

Evidence from epidemiologic studies has been inconsistent regarding the role of vitamin E in cancer incidence risk.

OBJECTIVE

The aim of this study was to evaluate the prospective association between baseline plasma vitamin E levels and subsequent cancer risk in Chinese adults with hypertension, and to identify effect modifiers.

DESIGN

A nested, case-control study was conducted from 20,702 hypertensive participants in the China Stroke Primary Prevention Trial, a randomized, double-blind, controlled trial, conducted from May 2008 to August 2013.

PARTICIPANTS

The current study included 229 new cancer cases and 229 controls matched for age (±1 year), sex, treatment group, and study site.

MAIN OUTCOME MEASURES

Plasma vitamin E was measured by liquid chromatography with tandem quadrupole mass spectrometers and plasma selenium was measured by inductively coupled plasma mass spectrometry using Thermo Fisher iCAP Q ICP-MS.

STATISTICAL ANALYSES

Odds ratios (OR) of cancer in relation to plasma concentrations of vitamin E were calculated using conditional logistic regression models.

RESULTS

Median follow-up duration was 4.5 years. Overall, vitamin E was not associated with subsequent risk of total cancer (per 1-mg/L [2.3 μmol/L] increase: OR 1.01, 95% CI 0.93 to 1.09) and non-gastrointestinal cancer (OR 1.10, 95% CI 0.98 to 1.24). However, there was a significant, inverse association between vitamin E and gastrointestinal cancer (OR 0.86, 95% CI 0.75 to 0.99), particularly esophageal cancer (OR 0.67, 95% CI 0.48 to 0.95). Moreover, high vitamin E decreased the risk of total cancer (OR 0.91, 95% CI 0.84 to 0.99) and gastrointestinal cancer (OR 0.83, 95% CI 0.73 to 0.95) among patients with high selenium levels (median≥83.7 μg/L [1.1 μmol/L]), and increased the risk of total cancer (OR 1.13, 95% CI 1.00 to 1.26) and non-gastrointestinal cancer (OR 1.25, 95% CI 1.03 to 1.50) among those with low selenium levels (<83.7 μg/L [1.1 μmol/L]).

CONCLUSIONS

This study suggests that higher levels of plasma vitamin E are associated with reduced risk of gastrointestinal cancer. High vitamin E decreased the risk of total cancer among patients with high selenium levels, but increased the risk of total cancer among those with low selenium levels.

Intravenous Vitamin C for Cancer Therapy - Identifying the Current Gaps in Our Knowledge

The use of intravenous vitamin C (IVC) for cancer therapy has long been an area of intense controversy. Despite this, high dose IVC has been administered for decades by complementary health care practitioners and physicians, with little evidence base resulting in inconsistent clinical practice. In this review we pose a series of questions of relevance to both researchers and clinicians, and also patients themselves, in order to identify current gaps in our knowledge. These questions include: Do oncology patients have compromised vitamin C status? Is intravenous the optimal route of vitamin C administration? Is IVC safe? Does IVC interfere with chemotherapy or radiotherapy? Does IVC decrease the toxic side effects of chemotherapy and improve quality of life? What are the relevant mechanisms of action of IVC? What are the optimal doses, frequency, and duration of IVC therapy? Researchers have made massive strides over the last 20 years and have addressed many of these important aspects, such as the best route for administration, safety, interactions with chemotherapy, quality of life, and potential mechanisms of action. However, we still do not know the answers to a number of fundamental questions around best clinical practice, such as how much, how often and for how long to administer IVC to oncology patients. These questions point the way forward for both basic research and future clinical trials.

Vitamin C - A new player in regulation of the cancer epigenome

Over the past few years it has become clear that vitamin C, as a provider of reduced iron, is an essential factor for the function of epigenetic regulators that initiate the demethylation of DNA and histones. Vitamin C deficiency is rare in the general population, but is frequently observed in patients with cancer. Genes encoding epigenetic regulators are often mutated in cancer, underscoring their central roles in carcinogenesis. In hematological cancers, such as acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), drugs that reverse epigenetic aberrations are now the standard of care. Recent in vitro studies suggest that vitamin C at physiological concentrations, combined with hypomethylating agents may act synergistically to cause DNA demethylation through active and passive mechanisms, respectively. Additionally, several recent studies have renewed interest in the use of pharmacological doses of vitamin C injected intravenously to selectively kill tumor cells. This review will focus on the potential of vitamin C to optimize the outcome of epigenetic therapy in cancer patients and alternatively to act as a therapeutic at high doses.

CURCUMIN IN COMBINATION WITH TRIPLE THERAPY REGIMES AMELIORATES OXIDATIVE STRESS AND HISTOPATHOLOGIC CHANGES IN CHRONIC GASTRITIS-ASSOCIATED HELICOBACTER PYLORI INFECTION

ABSTRACT BACKGROUND Helicobacter pylori (H. pylori) gastric infection is a main cause of inflammatory changes and gastric cancers. OBJECTIVE The aim of this study was finding the effects of curcumin on oxidative stress and histological changes in chronic gastritis associated with H. pylori. METHODS In a randomized clinical trial, patients were divided into two groups: a standard triple therapy group and triple therapy with curcumin group. Endoscopic and histological examinations were measured for all patients before and after 8 weeks. RESULTS Triple therapy with curcumin treatment group significantly decreased malondialdehyde markers, glutathione peroxides and increased total antioxidant capacity of the gastric mucosa at the end of study compared to baseline and triple regimen groups. In addition, the oxidative damage to DNA was significantly decreased in triple therapy with curcumin group at the end of study compared to baseline and compared to triple therapy (P<0.05 for both). Triple therapy group in combination with Curcumin significantly decreased all active, chronic and endoscopic inflammation scores of patients compared to the baseline and triple therapy group (P<0.05 for both). The eradication rate by triple therapy + curcumin was significantly increased compared to triple therapy alone (P<0.05). CONCLUSION Curcumin can be a useful supplement to improve chronic inflammation and prevention of carcinogenic changes in patients with chronic gastritis associated by H. pylori.

Coenzyme Q10 in combination with triple therapy regimens ameliorates oxidative stress and lipid peroxidation in chronic gastritis associated with H. pylori infection

Chronic gastritis associated with H. pylori infection causes oxidative stress in the stomach. This study aimed to evaluate the therapeutic effects of coenzyme q10 among gastric patients infected by H. pylori. By a clinical trial, chronic gastric patients infected by H. pylori were randomly divided into 2 groups: intervention and placebo. The placebo group received a standard triple therapy regimen, and the intervention group received the triple regimen + coenzyme Q10 (CoQ10). Mean inflammation score; serum levels of 3 serum markers were then compared. A total of 100 participants of whom 67% were female were evaluated. The mean age of participants was 59.4 ± 11.4 years. The mean inflammation score was considerably decreased at the end of the study, in the intervention group. The mean levels of total antioxidant capacity (TAC) and glutathione peroxidase (GPx) at the end of the study were reduced among the triple therapy group (P < .05, P =.03 respectively). The mean levels of TAC and GPx were significantly higher among the intervention group at the end of the study compared with those at the start of the study. The combination of triple therapy with CoQ10 demonstrated an effective outcome on the mucosal inflammation, and stress oxidative in patients with chronic gastritis.

Alteration of Lipid Profile in Patients with Head and Neck Malignancy

Lipids are the major cell membrane components, essential for various biological functions including cell growth and division for the maintenance of cell integrity of normal and malignant tissues. The changes in lipid profile have been associated since long with cancer and hypocholesterolemia has been observed in patients with cancers of various organs. The objective of the present study is to evaluate the alterations and clinical significance of plasma lipid profiles in untreated head and neck malignancies. The present case-control study comprises of newly diagnosed and histologically confirmed, 100 head and neck malignancy cases diagnosed between 1st July 2013 and 30th June 2014 in the Department of Otorhinolaryngology and Head and Neck Surgery, Gandhi Medical College, Bhopal. Fasting blood samples were collected and the lipid profile studied. In present study, the authors found that there is a preponderance of head and neck malignancy in the age group of 41-60 years, males having the higher incidence. Malignancy involving oral cavity were the commonest and majority were well differentiated. Statistically, there was a highly significant reduction of mean serum total cholesterol (TC), triglycerides and high density lipoproteins (HDL) in the subjects of head and neck malignancy as compared to the control group. TC and HDL were also found significantly lower among those with habit of tobacco consumption.

Ascorbate as a co-factor for fe- and 2-oxoglutarate dependent dioxygenases: physiological activity in tumor growth and progression

Ascorbate is a specific co-factor for a large family of enzymes known as the Fe- and 2-oxoglutarate-dependent dioxygenases. These enzymes are found throughout biology and catalyze the addition of a hydroxyl group to various substrates. The proline hydroxylase that is involved in collagen maturation is well known, but in recent times many new enzymes and functions have been uncovered, including those involved in epigenetic control and hypoxia-inducible factor (HIF) regulation. These discoveries have provided crucial mechanistic insights into how ascorbate may affect tumor biology. In particular, there is growing evidence that HIF-1-dependent tumor progression may be inhibited by increasing tumor ascorbate levels. However, rigorous clinical intervention studies are lacking. This review will explore the physiological role of ascorbate as an enzyme co-factor and how this mechanism relates to cancer biology and treatment. The use of ascorbate in cancer should be informed by clinical studies based on such mechanistic hypotheses.

Blood volatile compounds as biomarkers for colorectal cancer

Many recent studies have focused on the connection between the composition of specific volatile organic compounds (VOCs) in exhaled breath and various forms of cancer. However, the composition of exhaled breath is affected by many factors, such as lung disease, smoking, and diet. VOCs are released into the bloodstream before they are exhaled; therefore, the analysis of VOCs in blood will provide more accurate results than the analysis of VOCs in exhaled breath. Blood were collected from 16 colorectal cancer patients and 20 healthy controls, then solid phase microextraction-chromatography-mass spectrometry (SPME-GC-MS) was used to analysis the exhaled volatile organic compounds (VOCs). The statistical methods principal component analysis (PCA) and partial least-squares discriminant analysis (PLSDA) were performed to deal with the final dates. Three metabolic biomarkers were found at significantly lower levels in the group of CRC patients than in the normal control group (P<0.01): phenyl methylcarbamate, ethylhexanol, and 6-t-butyl-2,2,9,9-tetramethyl-3,5-decadien-7-yne. In addition, significantly higher levels of 1,1,4,4-tetramethyl-2,5-dimethylene-cyclohexane were found in the group of CRC patients than in the normal control group (P<0.05). Compared with healthy individuals, patients with colorectal adenocarcinoma exhibited a distinct blood metabolic profile with respect to VOCs. The analysis of blood VOCs appears to have potential clinical applications for CRC screening.

Estimation of plasma lipids and its significance on histopathological grades in oral cancer: Prognostic significance an original research

Background Objectives:

Alterations in the lipid profile have long been associated with various cancers because lipids play a key role in maintenance of cell integrity. This study was to estimate the plasma lipid levels in patients with oral cancer and to correlate the values with the histopathological grades.

Materials and Methods:

The study group included 50 patients with oral cancer aged between 20 and 60 years who had visited the Department of Oral Medicine and Radiology during the period of September 2005 to July 2007. After the histotopathological confirmation, their plasma lipid levels were estimated using auto analyzer and the data was statistically analyzed.

Results:

The study revealed a significant decrease in the total plasma lipid levels in patients with oral cancer in comparison with the standard values. Comparing the plasma lipid levels with the histopathological grades, we observed a significant variation in the levels of total cholesterol, very low density lipoprotein, low-density lipoprotein, high-density lipoprotein and triglycerides

Conclusion:

The variation in the levels of plasma cholesterol and other lipid constituents in patients with cancer might be due to their increased utilization by neoplastic cells for new membrane biosynthesis. This study was an attempt to estimate the plasma lipids in oral cancer patients and its significance on histopathological grades. We observed a relationship between lower plasma lipids and oral cancer. The result of our study strongly warrants an in-depth research with larger samples and a longer follow-up to consider the low plasma lipid status in oral cancer patients as a useful indicator to assess the course and prognosis of the disease.

Increased protein carbonylation and decreased antioxidant status in anemic H. pylori infected patients: effect of treatment

BACKGROUND/AIM

Collective evidences suggest the causal association of Helicobacter pylori infection with iron deficiency anemia. Generation of free radicals against this bacterium can lead to turbulence in oxidative-antioxidative system. This study was undertaken to evaluate the marker of oxidative protein injury, protein carbonylation, and total antioxidant status in anemic H. pylori-infected patients and to observe the alteration in them after treatment for 1 month with oral ferrous sulfate and anti-H. pylori therapy. Twenty anemic H. pylori-infected patients were randomly divided into 2 groups. The H. pylori-infected patients in Group I received both iron supplementation and anti-H pylori therapy, whereas patients in Group II received only the iron supplementation. Fifteen healthy volunteers served as controls. All the study parameters were estimated after 1 month of the treatment.

MATERIALS AND METHODS

Protein carbonylation and total antioxidant status were estimated using colorimetric method. Hematologic parameters were evaluated using Sysmex-K-100 automated cell counter.

RESULTS

In anemic H. pylori-infected patients, the protein carbonyls (PCOs) were significantly increased, whereas the total antioxidant status, iron, hemoglobin, and ferritin levels were significantly decreased compared with the controls. In Group I, while the PCOs level decreased significantly, there was a significant increase in the total antioxidant status, iron, hemoglobin, and ferritin levels after 1 month. No significant alterations were noted in the levels of PCOs, total antioxidant status, iron, hemoglobin, or ferritin in Group II patients after 1 month of the treatment.

CONCLUSIONS

The findings from this study indicate that treatment for both anemia and H. pylori infections is required for lowering the oxidative stress markers, which synergistically bring about an appropriate correction of anemia soon in these patients.

Alterations in serum lipid profile patterns in oral squamous cell carcinoma patients

AIM

Altered lipid profile patterns have been associated with malignancies because lipids play a pivotal role in the maintenance of cell integrity. The present study evaluated alterations in serum lipid profile in oral squamous cell carcinoma patients as well as its association with the habit of tobacco consumption.

MATERIALS AND METHODS

The study included 30 oral squamous cell carcinoma patients, 20 patients with the habit of tobacco consumption and 20 controls. Serum lipids, including (i) total cholesterol, (ii) LDL cholesterol (LDLC), (iii) HDL cholesterol (HDLC), (iv) VLDL cholesterol (VLDLC) and (v) triglycerides, were analyzed by spectrophotometric kits.

RESULTS

A significant decrease in serum total cholesterol (TC) levels, triglyceride levels (p = 0.007, p = 0.029 respectively) were observed in oral squamous cell carcinoma patients as compared to the healthy control group. The mean serum HDLC levels (p = 0.003) were significantly lowered in the tobacco habituates when compared to the healthy controls. The mean serum total cholesterol levels were significantly lower in subjects with oral squamous cell carcinoma (p = 0.000) as compared to the tobacco habituates. Likewise, LDLC levels and TC:HDLC ratios (p = 0.000 and p = 0.000 respectively) were significantly decreased in oral squamous cell carcinoma patients as compared to the tobacco habituates. Our data strengthens the evidence of an inverse relationship between serum lipid levels and oral squamous cell carcinoma.

CONCLUSION

The lower level of serum cholesterol and other lipid constituents in the patients is thought to be due to their increased usage by tumor cells for new membrane biogenesis.

CLINICAL SIGNIFICANCE

The lower serum lipid profile status serves as a useful indicator for gauging initial changes occurring in tumor cells. A detailed study of the cholesterol carrying lipoprotein transport mechanisms helps in better understanding of the underlying mechanisms of the regulation of serum cholesterol concentrations in cancer.

Comparative gastroprotective effect of post-treatment with low doses of rutin and cimetidine in rats

The anti-ulcerogenic potentials of low doses of rutin and cimetidine in ethanol-, acetic acid-, and stress-induced ulcers in rats have been evaluated and compared in this study. In each model, male Wistar rats were randomly divided into six groups (I-VI). Groups II-VI were administered 1 mL/100 g ethanol orally, 0.05 mL of 20% acetic acid submucosally or kept in a cold chamber for 6 h to induce ulcer in the ethanol-, acetic acid-, and stress-induced ulceration model, respectively. Thereafter, group III was post-treated with 300 mg/kg cimetidine and groups IV-VI with 20, 40, and 80 mg/kg rutin, respectively, while the control (group I) received distilled water in Tween 20. One hour after post-treatment, all groups were killed and the gastric ulcer index was calculated. Malondialdehyde (MDA) level, vitamin C content, and glutathione peroxidase (GPx) activity were evaluated in the gastric mucosa of animals. Post-treatment with rutin significantly reduced ulcerogen-induced gastric damage in all models. This effect was significant at all dose levels compared with the ulcer-induced groups. Rutin significantly reduced the MDA levels but increased the vitamin C content and GPx activity. Ulcer index and MDA level were highest in the ethanol-induced ulcer model while vitamin C content and GPx activity were lowest in the stress-induced ulcer model. The study showed that all three models of ulceration appeared to be linked to oxidative stress and also ascribed significant anti-ulcerogenic potential to rutin especially at lower doses of 20-80 mg/kg.

An urgent need to include risk-benefit analysis in clinical trials investigating conjugated linoleic acid supplements in cancer patients

Malnutrition and weight loss are common in patients with cancer, both factors could potentially affect the response and tolerance to treatment, decreased quality of life, and thus associate them with poor survival. Conjugated linoleic acid (CLA) is shown to have beneficial health effects in healthy and disease situations including chemoprotective properties in various experimental cancer models. However, the anticarcinogenic property of CLA in animal and tissue culture models could not be confirmed in the Netherlands Cohort Study on Diet and Cancer and a prospective cohort of Swedish women. Cancer patients are already at increased risk of anorexia and there are evidences that CLA suppresses appetite even in healthy individuals. Risk/benefit analysis of CLA supplementation has never been reported before and it is not clear whether any beneficial anti-tumor effect of CLA prevails over its anti-appetite and/or weight lowering side effect in these patients. I suggest that clinical trials investigating CLA supplements in cancer patients, measure appropriate variables such as food intake, weight, and appetite change to yield preliminary data for future trials. I also suggest that data from previous trials that have administered CLA supplements to cancer patients be re-analyzed retrospectively to attempt to find out any effect from routine nutritional measures such as weight, serum albumin and such as those.

Glutathione level and glutathione-dependent enzyme activities in blood serum of patients with gastrointestinal tract tumors

OBJECTIVES

Glutathione (GSH) and enzymes cooperating with it - glutathione peroxidase (GSHPx), glutathione S-transferase (GST) and glutathione reductase (GSHR) - play crucial role in cell defence against reactive oxygen species (ROS), which are implicated in tumor disease. The aim of this study was to determine if neoplastic diseases of gastrointestinal tract may influence blood GSH level and its dependent enzyme activity.

DESIGN AND METHODS

Blood serum was obtained before and after surgery from patients with gastric, liver and colorectal cancers, and colorectal cancer liver metastases. Lipid peroxidation and GSH levels, and GSH-dependent enzyme activities were determined by means of spectrophotometric methods.

RESULTS

Increased level of lipid peroxidation and significant differences in GSH level and GSHPx, GST and GSHR activities were observed in serum taken before and after surgery from patients with gastrointestinal tract tumors compared to those in control serum (from healthy blood donors).

CONCLUSIONS

Increase of lipid peroxidation and changes in GSH level and related enzyme activities, suggest oxidative stress in serum of patients with gastrointestinal tract tumor causes, which probably arise as a result of enormous production of ROS in the system. These alterations reflect the presence of functional defence mechanism against oxidative stress related firmly to the glutathione metabolism.

Effect of Monascus-fermented products on learning and memory in the SAMP8 mice

The purpose of this study was to evaluate the impact of Monascus-fermented products (MP) as regards certain changes in behavior for SAMP8 mice. Both male and female SAMP8 mice were fed a 0.03% MP diet from 3 mo of age to 11 mo of age. The results indicated that the grading score of passive avoidance behavior was significantly lower in the MP diet groups than in the control diet groups in both male and female SAMP8 mice (p < 0.05). The MP diet-augmented test-animal body weight, feed intake and feed efficiency did not differ significantly from the corresponding values for control mice. The MP diet-fed mouse group revealed significantly improved learning and memory as revealed by average escape-response testing score when comparing with control mice (p < 0.05). Further, the level of serum triglyceride and total cholesterol for the MP-fed group were shown to be significantly lower than for the control group of SAMP8 mice at 11 mo of age. The test mice fed an MP diet appeared to be significantly lower in aging score than the control group (p < 0.05). The MP diet-fed mouse group revealed significantly improved total antioxidation of liver. Subsequent to supplementation of SAMP8 mice diets with MP for a period of 8 mo, these MP-fed mice revealed significantly lower lipofuscin-cell numbers within the hippocampus (p < 0.05). The results suggest that dietary supplementation with MP might improve both learning and memory behaviour, and retard the aging process for SAMP8 mice.

Vitamin E: the evidence for multiple roles in cancer

There is accumulating evidence that vitamin E may have different roles in the prevention and treatment of cancer. The purpose of this review is to summarize and evaluate this evidence and to suggest future avenues of research. A comprehensive literature review of vitamin E and cancer was conducted. Articles were organized into the following categories: 1) cancer prevention, 2) direct antineoplastic activity, 3) augmentation of chemotherapy effects, and 4) attenuation or treatment of chemotherapy toxicity. The evidence was systematically evaluated using guidelines developed by the U.S. Preventative Services Task Force. There is evidence to suggest that those individuals with higher serum vitamin E levels and those receiving vitamin E supplementation have a decreased risk of some cancers, including lung, prostate, stomach, and gastrointestinal carcinoma. However, these results differed depending on the study design and the population studied. There is insufficient evidence to support anticancer activity and attenuation of chemotherapy toxicity by vitamin E. Vitamin E is likely to be important in the prevention of some cancers. The therapeutic role of vitamin E is poorly understood. Further research will be required before routine use of vitamin E in patients with cancer can be advocated in the clinical setting.

Micronutrients, antioxidants, and carcinoma of the gallbladder

OBJECTIVES

Nutrient deficiency in developing countries can be considered a significant contributory factor modifying the multistage process of carcinogenesis. Studies from different parts of the world have shown the deficiency of various micronutrients to be significantly associated with cancer. This study was undertaken to test the above hypothesis in patients with carcinoma of the gallbladder.

METHODS

Selenium (Se), zinc (Zn), copper (Cu), manganese (Mn), ascorbic acid (vitamin C), and alpha-tocopherol (vitamin E) were estimated in the serum, bile, and gallbladder tissue of 30 patients each of carcinoma of the gallbladder (group-I), cholelithiasis (group-II), and only in the serum of 30 age- and sex-matched healthy controls (group-III). The minerals were analyzed by atomic absorption spectrophotometer and vitamins by spectrophotometry.

RESULTS

The mean serum levels of Se, Zn, Mn, vitamin E, and vitamin C were significantly lower (P < 0.001) in group-I when compared with groups II and III. The mean biliary levels of Se and Zn (0.29, 3.45 mg/L) were reduced significantly (P < 0.001) in group-I when compared with group II (0.51, 5.2 mg/L). Mean tissue levels of Se and Zn were also significantly lower (P < 0.001) in group I (2.75, 43.09 microg/g) compared to group II (3.90, 61.37 microg/g). However, no significant difference was observed in tissue concentration of Mn, vitamin C, and vitamin E. Cu levels and Cu/Zn ratio showed a highly significant (P < 0.001) increase in serum, bile, and gallbladder tissue in carcinoma of the gallbladder compared to the other two groups.

CONCLUSIONS

The data supports an association between lower levels of Se, Zn, vitamin E, and risk of carcinoma of the gallbladder and suggest that Cu/Zn ratio could be a useful parameter in evaluating the patients of carcinoma of the gallbladder.

The effects of endurance exercise and vitamin E on oxidative stress in the elderly

To examine the effects of exercise and vitamin E supplementation on oxidative stress in older adults, 59 participants, age 76.3 +/- 4.2 years, were randomly assigned to 1 of 4 groups: an exercise group taking placebos (EGP) or vitamin E (EGE) or a sedentary group taking placebos (SGP) or vitamin E (SGE). Measures included weight, VO2max, blood pressure (BP), and serum concentrations of vitamin E and lipid hydroperoxide (LOOH). At the end of the 16-week trial, the EGP and EGE had significant increases in VO2max and significant decreases in resting BP, weight, and LOOH concentrations (P < 0.05). The SGE had significant decreases in LOOH and BP (P < 0.05). There were no significant changes in the SGP (P > 0.05). The results suggest that endurance exercise in combination with vitamin E reduces oxidative stress, improves aerobic fitness, and reduces BP and weight in older adults. Even sedentary participants who take vitamin E may reduce oxidative stress and lower BP.

Serum and plasma concentration of oxidant and antioxidants in patients of Helicobacter pylori gastritis and its correlation with gastric cancer

Serum superoxide dismutase, plasma ascorbic acid and lipid peroxidation in H. pylori gastritis and gastric cancer patients were compared with values for age matched healthy subjects. Serum superoxide dismutase and serum malondialdehyde were analyzed spectrophotometrically whereas plasma ascorbic acid was determined by colorimetric method. Significant increase in serum superoxide dismutase and serum malondialdehyde and significant decrease in plasma ascorbic acid were observed in H. pylori gastritis and gastric cancer patients compared to control subjects. The concentration of serum superoxide dismutase and serum malondialdehyde was significantly higher and plasma ascorbic acid was significantly lower in gastric cancer as compared to H. pylori gastritis patients. Our results demonstrate that a correlation existed between the concentration of serum superoxide dismutase, plasma ascorbic acid and lipid peroxidation in H. pylori gastritis and gastric cancer patients.

Nutrition and diet in the development of gastrointestinal cancer

Diet plays a role in the prevention and development of gastrointestinal cancers. The majority of available research consists of case-control studies, but the number of clinical trials is growing. The dietary recommendations to reduce gastrointestinal cancer risk include lowering total energy, fat, and saturated fat intake; avoidance of grilled and smoked foods; avoidance of alcohol; and increasing intake of fruits, vegetables, and fiber. Studies of esophageal cancer support these dietary approaches, with the exception of dietary fat reduction and increased green tea intake. For gastric cancer, consuming additional fruits and vegetables, including those high in ascorbic acid, may reduce risk, and the capacity for diet to alter Helicobacter pylori infection should be explored. Recent interventional trials do not support a role for high-fiber or low-fat diets in reducing development of colon adenomas, although the evidence does not rule out efficacy at earlier stages of disease. Finally, the evidence for a relationship between pancreatic cancer and diet remains sparse and warrants additional investigation.

Age-related changes in redox status of rat serum

Aging and age-related diseases are known to be associated with increased oxidative stress. To protect against the deleterious effects of oxidative stress, a well-co-ordinated network of enzymatic and nonenzymatic anti-oxidant defense systems is essential. In the present study, we investigated the age-related redox status of serum by analyzing hydrogen peroxide, hydroxyl radical, superoxide-scavenging abilities, and other redox markers. Results showed the anti-oxidative capacity to be significantly decreased in serum of aged rats, which was accompanied by a marked increase in peroxide levels. Our analyses also revealed that levels of nitrated proteins, induced by peroxynitrite treatment, were higher in old rats than in young rats. Our results clearly indicated that the serum redox balance shifted toward oxidation during aging. To further confirm this age-related redox shift, we quantified the changes in thiol content. The total thiol level was found to be significantly decreased in the aged group. We also noticed an age-related reduction in serum albumin, which may be partially responsible for the decreased serum thiol levels. A similar pattern can be explained by low levels of serum GSH in old rats compared to young rats. The significance of the present study is the data showing increased oxidative stress in serum during aging, attributed to a decrease in major antioxidant components in serum.

Alpha-tocopherol succinate inhibits growth of gastric cancer cells in vitro

BACKGROUND

Vitamin E in the form of alpha-tocopherol succinate (ATS) has been shown to inhibit growth of several cancer cell lines in vitro, including pancreas, breast, and prostate. No data exist on the effect of ATS on gastric cancer cell viability.

METHODS

A gastric cancer cell line in suspension form, KATO-III, was plated in 96-well plates at 30,000 cells per well with 100 microl RPMI media. The cells were allowed to incubate for 24 h and were then treated with ATS at doses of 25, 50, or 100 microg/ml. The ATS was dissolved in 1% EtOH solution and control cells received an identical solution of EtOH without ATS. Treated cells were incubated for 24, 48, or 72 h. At the completion of the treatment period, MTT assay was performed to determine cell viability. Statistical analysis was performed using Student's t test.

RESULTS

All doses of ATS resulted in inhibition of growth of the KATO-III cells. Both 100 and 50 microg/cc doses inhibited growth at all time points (P<0.005), with 48- and 72-h treatments more effective than 24-h treatment. At 24 and 48 h, 100 microg/cc was more effective at inhibition of growth than 50 microg/ml (P<0.005), but by 72 h the effects of the doses were equivalent; 25 microg/ml inhibited cell growth only at 48 and 72 h. At all time points, 50 and 100 microg/ml doses were more effective at inhibiting cell growth than 25 microg/ml. Conclusions. ATS inhibits gastric carcinoma cell growth in vitro in a dose- and time-dependent fashion. In vivo studies are indicated to further evaluate the potential benefit of this antioxidant against gastric cancer.

Ascorbic acid secretion in the human stomach and the effect of gastrin

AIM: To investigate the changes of gastric mucosal ascorbic acid secretion in patients with nonulcer dyspepsia and the effect of gastrin on it, and to relate any observed changes to H. pylori infection and mucosal histology.

METHODS: Ascorbic acid secretions in patients were examined by collecting continuously gastric juice for one hour after having aspirated and discarded fasting gastric juice. Using the clearance rate (mL/min) of ascorbic acid from blood to gastric juice represented ascorbic acid secretion in the gastric mucosa. Ascorbic acid concentrations in plasma and juice were measured by ferric reduced method.

RESULTS: Gastric ascorbic acid secretions in H. pylori -positive patients (1.46 mL/min, range 0.27-3.78) did not significantly differ from those in H. pylori -negative patients (1.25 mL/min, 0.47-3.14) (P > 0.05). There were no significant differences in ascorbic acid secretions between patients with mild (1.56 mL/min, 0.50-3.30), moderate (1.34 mL/min, 0.27-2.93) and severe (1.36 mL/min, 0.47-3.78) inflammation (P > 0.05). There were no significant differences in ascorbic acid secretions between patients without activity (1.45 mL/min, 0.27-3.14) and with mild (1.32 mL/min, 0.61-2.93), moderate (1.49 mL/min, 0.50-3.78) and severe (1.43 mL/min, 0.51-3.26) activity of chronic gastritis either (P > 0.05). Ascorbic acid secretions in patients with severe atrophy (0.56 mL/min, 0.27-1.20) were markedly lower than those in patients with out atrophy (1.51 mL/min, 0.59-3.30) and with mild (1.43 mL/min, 0.53-3.78) and moderate (1.31 mL/min, 0.47-3.16) atrophy (P < 0.005). There was a significant negative correlation between ascorbic acid secretion and severity of atrophy (correlation coefficient = -0.43, P < 0.005). After administration of pentagastrin, ascorbic acid secretions were markedly elevated (from 1.39 mL/min, 0.36-2.96 to 3.53 mL/min, 0.84-5.91) (P < 0.001).

CONCLUSION: Ascorbic acid secretion in gastric mucosa is not affected by H. pylori infection. Gastric ascorbic acid secretion is markedly related to the severity of atrophy, whereas not related to the severity of inflammation and activity. Gastrin may stimulate gastric ascorbic acid secretion. A decreased ascorbic acid secretion may be an important factor in the link between atrophic gastritis and gastric carcinogenesis.

Vitamin E serum levels and gastric cancer: results from a cohort of patients in Tuscany, Italy

Alpha-tocopherol has been reported to play an important role against oxidative damage and in the inhibition of cell transforming and mutagenesis. We analysed vitamin E serum levels in 51 cases of patients affected by gastric cancer at different stages of the disease, and in 49 age-matched controls. All patients had normal values of alpha-tocopherol. However, when patients have been grouped according to histotype of gastric lesions, a significant vitamin E increase has been found in diffuse gastric cancer histotype compared to the intestinal histotype. Our results suggest that a correlation between vitamin E serum levels and gastric cancer histotype should be considered.