Experimental study on mechanism and protection of stress ulcer produced by explosive noise

Gut Microbiota, Its Role in Induction of Alzheimer's Disease Pathology, and Possible Therapeutic Interventions: Special Focus on Anthocyanins

The human gut is a safe environment for several microbes that are symbiotic and important for the wellbeing of human health. However, studies on gut microbiota in different animals have suggested that changes in the composition and structure of these microbes may promote gut inflammation by releasing inflammatory cytokines and lipopolysaccharides, gut-wall leakage, and may affect systemic inflammatory and immune mechanisms that are important for the normal functioning of the body. There are many factors that aid in the gut’s dysbiosis and neuroinflammation, including high stress levels, lack of sleep, fatty and processed foods, and the prolonged use of antibiotics. These neurotoxic mechanisms of dysbiosis may increase susceptibility to Alzheimer’s disease (AD) and other neurodegenerative conditions. Therefore, studies have recently been conducted to tackle AD-like conditions by specifically targeting gut microbes that need further elucidation. It was suggested that gut dyshomeostasis may be regulated by using available options, including the use of flavonoids such as anthocyanins, and restriction of the use of high-fatty-acid-containing food. In this review, we summarize the gut microbiota, factors promoting it, and possible therapeutic interventions especially focused on the therapeutic potential of natural dietary polyflavonoid anthocyanins. Our study strongly suggests that gut dysbiosis and systemic inflammation are critically involved in the development of neurodegenerative disorders, and the natural intake of these flavonoids may provide new therapeutic opportunities for preclinical or clinical studies.

Cumulative exposure to nighttime environmental noise and the incidence of peptic ulcer

BACKGROUND

Exposure to noise poses auditory and non-auditory effects on health. The gastrointestinal tract is considered as the site of adverse reactions to noise-induced stress; little attention has been paid to a potential link between noise and peptic ulcers.

OBJECTIVES

The aim of this study was to investigate whether cumulative exposure to environmental noise affects the incidence of peptic ulcer in adults.

METHODS

We analyzed the data from the National Health Insurance Service-National Sample Cohort (2002-2013). The final study sample comprised 217,308 adults assessed for gastric ulcer and 249,514 adults assessed for duodenal ulcer. The diagnosis of gastric (ICD-10: K25) and duodenal (ICD-10: K26) ulcers during an 8-year follow-up (2006-2013). Environmental noise data was obtained from the National Noise Information System, a nationwide monitors system of noise.

RESULTS

During the follow-up period, gastric ulcers occurred in 32.1% subjects and duodenal ulcers occurred in 10.7% subjects. The rate of diagnosis for gastric and duodenal ulcers was increased with the increases in cumulative mean levels of nighttime environmental noise. With increases in the increase in interquartile range (IQR) of nighttime noise, the hazard ratio (HR) was significantly increased by 12% (HR = 1.12; 95% CI, 1.10-1.13) for gastric ulcer and 17% (HR = 1.17; 95% CI, 1.15-1.20) for duodenal ulcer based on the fully adjusted model.

CONCLUSION

Our finding supports previous reports on the damaging effect of environmental noise on the gastrointestinal tract and suggests that cumulative exposure to environmental nighttime noise affects the development of peptic ulcers.

Effects of Psychological, Environmental and Physical Stressors on the Gut Microbiota

Stress, a ubiquitous part of daily human life, has varied biological effects which are increasingly recognized as including modulation of commensal microorganisms residing in the gastrointestinal tract, the gut microbiota. In turn, the gut microbiota influences the host stress response and associated sequelae, thereby implicating the gut microbiota as an important mediator of host health. This narrative review aims to summarize evidence concerning the impact of psychological, environmental, and physical stressors on gut microbiota composition and function. The stressors reviewed include psychological stress, circadian disruption, sleep deprivation, environmental extremes (high altitude, heat, and cold), environmental pathogens, toxicants, pollutants, and noise, physical activity, and diet (nutrient composition and food restriction). Stressors were selected for their direct relevance to military personnel, a population that is commonly exposed to these stressors, often at extremes, and in combination. However, the selected stressors are also common, alone or in combination, in some civilian populations. Evidence from preclinical studies collectively indicates that the reviewed stressors alter the composition, function and metabolic activity of the gut microbiota, but that effects vary across stressors, and can include effects that may be beneficial or detrimental to host health. Translation of these findings to humans is largely lacking at present. This gap precludes concluding with certainty that transient or cumulative exposures to psychological, environmental, and physical stressors have any consistent, meaningful impact on the human gut microbiota. However, provocative preclinical evidence highlights a need for translational research aiming to elucidate the impact of stressors on the human gut microbiota, and how the gut microbiota can be manipulated, for example by using nutrition, to mitigate adverse stress responses.

Association of occupational exposures and work characteristics with the occurrence of gastrointestinal disorders

BACKGROUND

Work is a daily activity with various conditions, exposures, and habits that may affect health either positively or negatively. Aim of this study was to investigate the relationship between occupational factors and conditions, and the occurrence of gastrointestinal disorders.

METHODS

We enrolled in this study a sample of 891 consecutive individuals, who were examined by standard colonoscopy and gastroscopy and interviewed regarding their working conditions and exposures. Consecutively, data were statistically analyzed to explore possible associations.

RESULTS

Peptic ulcer diagnosis was associated with reports of muscle pain/headache [odds ratio (OR): 3.656, 95 % confidence interval (95% CI): 1.898-7.043], with working in shifts (OR: 2.463, 95% CI: 1.058-5.731), and with the presence of occupational stress (OR: 2.283, 95% CI: 1.162-4.486). Gastritis was associated with muscle pain/headache (OR: 2.258, 95% CI: 1.096-4.652), shift work (OR: 3.535, 95% CI: 1.345-9.29), occupational stress (OR: 2.182, 95% CI: 1.072-4.444), and sedentary work (OR 0.275 lower risk 95% CI: 0.113-0.671). Ulcerative colitis was associated with muscle pain/headache (OR: 6.211, 95% CI: 2.162-17.840) and occupational stress (OR: 6.418, 95% CI: 2.243-18.361), while Crohn's disease diagnosis with muscle pain/headache (OR: 3.554, 95% CI: 1.628-7.759), frequent ordering food at work (OR: 4.928, 95% CI: 2.3-10.559), occupational stress (OR: 3.023, 95% CI: 1.413-6.469), work with intense physical activity (OR: 0.665 lower risk, 95% CI: 0.252-0.758). Colon cancer diagnosis was associated with frequent ordering food at work (OR: 2.739, 95% CI: 1.268-5.916) and occupational stress (OR: 3.175, 95% CI: 1.384-7.286), while stomach cancer diagnosis with ordering food at work (OR: 2.794, 95% CI: 1.154-6.763) and exposure to dust (OR: 5.650, 95% CI: 1.551-20.582). Finally, presence of polyps was associated with ordering food at work (OR: 2.154, 95% CI: 1.135-4.091), and constipation with ordering food at work (OR: 2.869, 95% CI: 1.451-5.672), occupational stress (OR: 2.112, 95% CI: 1.097-4.066), and occupational noise (OR: 0.248, 95% CI: 0.084-0.737).

CONCLUSION

The incidence of the gastrointestinal diseases is affected by occupational exposures and related lifestyle habits. HIPPOKRATIA 2017, 21(2): 74-79.

Effect of explosive noise on gastrointestinal transit and plasma levels of polypeptide hormones

AIM: To investigate the effect of firing noise on gastrointestinal transit and probe its mechanism by measuring the levels of plasma polypeptide hormones.

METHODS: A total of 64 SD rats were randomly divided into a control group and three stimulating groups. Firing noise of different intensity by sub-machine guns was used as inflicting factor. The effect of firing noise on liquid substance gastrointestinal transit and solid substance gastrointestinal transit was observed by measuring the ratio of carbon powder suspension transmitting and barium sticks transmitting respectively. Plasma levels of polypeptide hormones were measured by radio-immunoassay.

RESULTS: The noise accelerated gastrointestinal transit of solid food by more than 80 db;and accelerated gastrointestinal transit of liquid food significantly by more than 120 db. Meantime, plasma levels of plasma motilin (MTL)(157.47±16.08; 151.90±17.08), somatostatin (SS)(513.97±88.77; 458.25±104.30), substance P (SP)(115.52±20.70; 110.28±19.96) and vasoactive intestinal peptide (VIP) (214.21±63.17; 251.76±97.24) remarkably changed also.

CONCLUSION: Within a certain intensity range, the firing noise changes the levels of rat plasma gastrointestinal hormones, but the gastrointestinal transit is still normal. Beyond the range, the noise induces plasma hormone levels disturbance and gastrointestinal transit disorder.

Anatomic and technical skill factor of gastroduodenal complication in post-transarterial embolization for hepatocellular carcinoma: A retrospective study of 280 cases

AIM: To reduce the possibility of gastroduodenal complications. The purpose of this retrospective study was to survey the literature and compare and discuss the incidence of post-transarterial embolization (TAE) gastroduodenal complications.

METHODS: We found reports describing 280 cases of hepatocellular carcinoma with TAE procedures done during the past 4 years and selected all of them for our study. Amongst these cases, 86 were suspected of suffering gastroduodenal complications within one month of post-TAE treatment. Fifteen of these cases were proved by pan-endoscopy to have gastroduodenal erosions or ulcerations. We reviewed the angiographic pictures in patient records to evaluate the possibility that anatomic and technical skill factors could explain the complications.

RESULTS: Amongst the 15 cases, 9 were primary lesions of the antrum and prepylorus; 4 had duodenal ulcer or erosions; 2 had mid-body lesions; none showed a lesion at the fundus or cardia region. Three cases had not received TAEs using our ideal method, and may be associated with possible regurgitation of gel-foam pieces into the right or left gastric arteries. Two cases involved sub-selective embolization at a distal point on the hepatic artery; one case was found by angiography to have complete occlusion of the celiac trunk.

CONCLUSION: Comparing our results with past cases of post-TAE gastroduodenal complications, we surmise that our relatively low incidence (5.3%) of gastric complications might be explained by our concerted efforts to improve our technical skills in multi-sequential, selective and super-selective approaches to the embolization of tumor vessels.

Effects of transections of cervical sympathetic trunk on gastric mucosal blood flow and ET-1 in water immersion restrain rats

AIM: To investigate the effect of transections of the cervical sympathetic trunk (TCST) on the gastric mucosal blood flow (GMBF) in water immersion restrain rats.

METHODS: A total of 30 male Sprague-Dawleys rats were randomly allocated into three groups: control group (Group I), water immersion restrain group (Group II) and TCST followed by water immersion restrain (Group III). Superior cervical ganglion were exposed and splited, but not cut off in Group I and Group II. In Group III, we cut off and ligated the cervical sympathetic nerve trunk below 3 mm of superior cervical ganglion. Then the rats of Group II and Group III were vertically immersed into water (23±1 ℃). Six hours later, GMBF were measured by laser Doppler blood stream meter. And we evaluated the gastric mucosal ulcer index (UI) according to Guth score.

RESULTS: There was mucosal bleeding and erosion in Group II, Group III was obviously relived as compared with Group II. The GMBF was 68.9±12.7; 130.0±14.5 (PU) in Group II and Group III respectively, while the UI was 50.1±12.3; 26.6±9.4.(P<0.01). The GMBF and UI was significant negative correlation (= -0.847, P<0.01). ET-1 in plasma and gastric mucosa in Group II were higher than those in Group I. ET-1 in plasma in Group III were higher than that in Group I, while they were lower than that in Group II. ET-1 in plasma had a moderate negative-correlation with GMBF.

CONCLUSION: Increased the GMBF due to TCST may contribute to attenuation in the lesion of gastric muscoa in water immersion restrain rats, and it may have something to do with ET-1 in plasma and gastric mucosa.

Sleep deprivation increase the expression of inducible heat shock protein 70 in rat gastric mucosa

AIM: To investigate if sleep deprivation is able to increase the expression of inducible heat shock protein 70 in gastric mucosa and its possible role in mucosal defense.

METHODS: Rats for sleep disruption were placed inside a computerized rotating drum, gastric mucosa was taken from rats with 1, 3 and 7 d sleep deprivation. RT-PCR, immunohistochemistry and Western blotting were used to determine the expression of heat shock protein 70. Ethanol (500 mL·L^-1, i.g.) was used to induce gastric mucosa damage.

RESULTS: RT-PCR, Western blotting and immunostaining confirmed that the sleep deprivation as a stress resulted in significantly greater expression of inducible heat shock protein 70 in gastric mucosa of rats. After the 500 mL·L^-1 ethanol challenge, the ulcer area found in the rats with 7 d sleep deprivation (19.15 ± 4.2) mm² was significantly lower (P < 0.01) than the corresponding control (53.7 ± 8.1) mm².

CONCLUSION: Sleep deprivation as a stress, in addition to lowering the gastric mucosal barrier, is able to stimulate the expression of inducible heat shock protein 70 in gastric mucosa of rats, the heat shock protein 70 may play an important role in gastric mucosal protection.