Slow-release L-cysteine capsule prevents gastric mucosa exposure to carcinogenic acetaldehyde: results of a randomised single-blinded, cross-over study of Helicobacter-associated atrophic gastritis

The Impact of Tobacco Smoking and Alcohol Consumption on the Development of Gastric Cancers

Chronic infection of Helicobacter pylori is considered the principal cause of gastric cancers, but evidence has accumulated regarding the impact of tobacco smoking and alcohol consumption on the development of gastric cancers. Several possible mechanisms, including the activation of nicotinic acetylcholine receptors, have been proposed for smoking-induced gastric carcinogenesis. On the other hand, local acetaldehyde exposure and ethanol-induced mucosal inflammation have been proposed as the mechanisms involved in the development of gastric cancers in heavy alcohol drinkers. In addition, genetic polymorphisms are also considered to play a pivotal role in smoking-related and alcohol-related gastric carcinogenesis. In this review, we will discuss the molecular mechanisms involved in the development of gastric cancers in relation to tobacco smoking and alcohol consumption.

Efficacy evaluation of upper gastrointestinal endoscopy screening for secondary prevention of gastric cancer using the standardized detection ratio during a medical check-up in Japan

We used standardized detection ratio to evaluate the quality of nasal upper gastrointestinal endoscopy screening for the secondary prevention of gastric cancer, and examined the gastric cancer risk in the era of total Helicobacter pylori (H. pylori) eradication. We performed 21,931 upper gastrointestinal endoscopies, 77 subjects were diagnosed with gastric cancer. Of these, 28 had gastric cancer after H. pylori eradication, 47 had gastric cancer with H. pylori-positive or others, and 2 had H. pylori-negative gastric cancer. The Standardized detection ratios for men and women were 5.33 and 4.82, respectively. Multivariable logistic regression analyses performed exclusively on first endoscopy subjects, excluding H. pylori-negative gastric cancer, revealed that smoking was a risk factor for developing gastric cancer (adjusted odds ratio, 3.31; 95% confidence interval, 1.65-6.64; p = 0.001). A statistically significant interaction was found between daily alcohol consumpption and H. pylori eradication on gastric cancer development (p = 0.005). In conclusion, relatively high standardized detection ratio values suggest that an appropriate endoscopic diagnosis of gastric cancer should be performed during a medical check-up. Smoking is a risk factor for developing gastric cancer, and continued alcohol consumption suggests a possible risk for developing gastric cancer after H. pylori eradication.

Acetaldehyde as a Food Flavoring Substance: Aspects of Risk Assessment

The Senate Commission on Food Safety (SKLM) of the German Research Foundation (DFG) has reviewed the currently available data in order to assess the health risks associated with the use of acetaldehyde as a flavoring substance in foods. Acetaldehyde is genotoxic in vitro. Following oral intake of ethanol or inhalation exposure to acetaldehyde, systemic genotoxic effects of acetaldehyde in vivo cannot be ruled out (induction of DNA adducts and micronuclei). At present, the key question of whether acetaldehyde is genotoxic and mutagenic in vivo after oral exposure cannot be answered conclusively. There is also insufficient data on human exposure. Consequently, it is currently not possible to reliably assess the health risk associated with the use of acetaldehyde as a flavoring substance. However, considering the genotoxic potential of acetaldehyde as well as numerous data gaps that need to be filled to allow a comprehensive risk assessment, the SKLM considers that the use of acetaldehyde as a flavoring may pose a safety concern. For reasons of precautionary consumer protection, the SKLM recommends that the scientific base for approval of the intentional addition of acetaldehyde to foods as a flavoring substance should be reassessed.

Paradoxical association between dyspepsia and autoimmune chronic atrophic gastritis: Insights into mechanisms, pathophysiology, and treatment options

BACKGROUND

Autoimmune gastritis (AIG) is a progressive, chronic, immune-mediated inflammatory disease characterized by the destruction of gastric parietal cells leading to hypo/anacidity and loss of intrinsic factor. Gastrointestinal symptoms such as dyspepsia and early satiety are very common, being second in terms of frequency only to anemia, which is the most typical feature of AIG.

AIM

To address both well-established and more innovative information and knowledge about this challenging disorder.

METHODS

An extensive bibliographical search was performed in PubMed to identify guidelines and primary literature (retrospective and prospective studies, systematic reviews, case series) published in the last 10 years.

RESULTS

A total of 125 records were reviewed and 80 were defined as fulfilling the criteria.

CONCLUSION

AIG can cause a range of clinical manifestations, including dyspepsia. The pathophysiology of dyspepsia in AIG is complex and involves changes in acid secretion, gastric motility, hormone signaling, and gut microbiota, among other factors. Managing dyspeptic symptoms of AIG is challenging and there are no specific therapies targeting dyspepsia in AIG. While proton pump inhibitors are commonly used to treat dyspepsia and gastroesophageal reflux disease, they may not be appropriate for AIG. Prokinetic agents, antidepressant drugs, and non-pharmacological treatments may be of help, even if not adequately evidence-based supported. A multidisciplinary approach for the management of dyspepsia in AIG is recommended, and further research is needed to develop and validate more effective therapies for dyspepsia.

L-Cysteine Containing Vitamin Supplement Which Prevents or Alleviates Alcohol-related Hangover Symptoms: Nausea, Headache, Stress and Anxiety

AIMS

Alcohol-related hangover symptoms: nausea, headache, stress and anxiety cause globally considerable amount of health problems and economic losses. Many of these harmful effects are produced by alcohol and its metabolite, acetaldehyde, which also is a common ingredient in alcohol beverages. The aim of the present study is to investigate the effect of the amino acid L-cysteine on the alcohol/acetaldehyde related aftereffects.

METHODS

Voluntary healthy participants were recruited through advertisements. Volunteers had to have experience of hangover and/or headache. The hangover study was randomized, double-blind and placebo-controlled. Nineteen males randomly swallowed placebo and L-cysteine tablets. The alcohol dose was 1.5 g/kg, which was consumed during 3 h.

RESULTS

The primary results based on correlational analysis showed that L-cysteine prevents or alleviates hangover, nausea, headache, stress and anxiety. For hangover, nausea and headache the results were apparent with the L-cysteine dose of 1200 mg and for stress and anxiety already with the dose of 600 mg.

CONCLUSIONS

L-cysteine would reduce the need of drinking the next day with no or less hangover symptoms: nausea, headache, stress and anxiety. Altogether, these effects of L-cysteine are unique and seem to have a future in preventing or alleviating these harmful symptoms as well as reducing the risk of alcohol addiction.

Prophylactic effect of Lactobacillus plantarum KSFY06 on HCl/ethanol-induced gastric injury in mice

The present study was conducted to determine the prophylactic effect of Lactobacillus plantarum KSFY06 (LP-KSFY06) on HCl/ethanol-induced gastric injury in Kunming mice. The experimental mice were allocated into six groups: the normal group, HCl/ethanol treated group, HCl/ethanol + ranitidine treated group, HCl/ethanol + Lactobacillus delbrueckii subsp. Bulgaricus (LB) treated group, HCl/ethanol + low concentration of Lactobacillus plantans KSFY06 (LP-KSFY06-L) treated group, and HCl/ethanol + high concentration of Lactobacillus plantans KSFY06 (LP-KSFY06-H) treated group. The changes in daily body weight and food intake of the mice in the HCl/ethanol + LP-KSFY06-H treated group were the closest to those of the HCl/ethanol + ranitidine treated and normal groups. LP-KSFY06 significantly inhibited the formation of gastric mucosal lesions, reduced the area of gastric lesions, inhibited gastric-juice secretion, and increased pH compared with the HCl/ethanol treated group. After the treatment, the serum interleukin-6 (IL)-6, IL-12, tumor necrosis factor-α (TNF-α), and interferon-γ levels and the gastric-tissue IL-6 and IL-12 levels in the LP-KSFY06 (including LP-KSFY06-L and LP-KSFY06-H) group decreased compared with those in the HCl/ethanol treated group. The level of serum and gastric tissue malondialdehyde was lower and the nitric oxide, total superoxide dismutase, and glutathione activities in the LP-KSFY06 treated mice were higher than those in the HCl/ethanol treated mice. Quantitative polymerase chain reaction analysis and western blot analysis showed that LP-KSFY06 increased the mRNA and protein expression of the epidermal growth factor, epidermal growth factor receptor, vascular endothelial growth factor, inhibitor kappaB-α, neuronal nitric oxide synthase, and endothelial NOS and reduced the mRNA and protein expression of nuclear factor kappaB, inducible NOS, cyclooxygenase-2, TNF-α, and IL-1β in gastric tissues compared with the HCl/ethanol treated mice. These experimental results showed that a high concentration (1.0 × 109 CFU per kg B.W.) of LP-KSFY06 had a stronger effect on preventing gastric injury than a low concentration (1.0 × 108 CFU per kg B.W.) of LP-KSFY06. These results suggest that LP-KSFY06 has a potential probiotic effect in preventing gastric injury.

Local Acetaldehyde-An Essential Role in Alcohol-Related Upper Gastrointestinal Tract Carcinogenesis

The resident microbiome plays a key role in exposure of the upper gastrointestinal (GI) tract mucosa to acetaldehyde (ACH), a carcinogenic metabolite of ethanol. Poor oral health is a significant risk factor for oral and esophageal carcinogenesis and is characterized by a dysbiotic microbiome. Dysbiosis leads to increased growth of opportunistic pathogens (such as Candida yeasts) and may cause an up to 100% increase in the local ACH production, which is further modified by organ-specific expression and gene polymorphisms of ethanol-metabolizing and ACH-metabolizing enzymes. A point mutation in the aldehyde dehydrogenase 2 gene has randomized millions of alcohol consumers to markedly increased local ACH exposure via saliva and gastric juice, which is associated with a manifold risk for upper GI tract cancers. This human cancer model proves conclusively the causal relationship between ACH and upper GI tract carcinogenesis and provides novel possibilities for the quantitative assessment of ACH carcinogenicity in the human oropharynx. ACH formed from ethanol present in "non-alcoholic" beverages, fermented food, or added during food preparation forms a significant epidemiologic bias in cancer epidemiology. The same also concerns "free" ACH present in mutagenic concentrations in multiple beverages and foodstuffs. Local exposure to ACH is cumulative and can be reduced markedly both at the population and individual level. At best, a person would never consume tobacco, alcohol, or both. However, even smoking cessation and moderation of alcohol consumption are associated with a marked decrease in local ACH exposure and cancer risk, especially among established risk groups.

Key role of local acetaldehyde in upper GI tract carcinogenesis

Ethanol is neither genotoxic nor mutagenic. Its first metabolite acetaldehyde, however, is a powerful local carcinogen. Point mutation in ALDH2 gene proves the causal relationship between acetaldehyde and upper digestive tract cancer in humans. Salivary acetaldehyde concentration and exposure time are the two major and quantifiable factors regulating the degree of local acetaldehyde exposure in the ideal target organ, oropharynx. Instant microbial acetaldehyde formation from alcohol represents >70% of total ethanol associated acetaldehyde exposure in the mouth. In the oropharynx and achlorhydric stomach acetaldehyde is not metabolized to safe products, instead in the presence of alcohol it accumulates in saliva and gastric juice in mutagenic concentrations. A common denominator in alcohol, tobacco and food associated upper digestive tract carcinogenesis is acetaldehyde. Epidemiological studies on upper GI tract cancer are biased, since they miss information on acetaldehyde exposure derived from alcohol and acetaldehyde present in 'non-alcoholic' beverages and food.