Effect of ethanol on prostaglandin E2 receptor in rat submandibular salivary glands

Ethanol- and Cigarette Smoke-Related Alternations in Oral Redox Homeostasis

Alcohol abuse as well as smoking cigarettes has been proven to negatively affect the oral environment. The aim of this work was to provide a systematic review of the literature on the influence of ethanol and cigarette smoking on oral redox homeostasis. A search was performed for scientific articles indexed in the PubMed, Medline and Web of Science databases. We identified 32,300 articles, of which 54 were used for the final review, including the results from 2000 to 2021. Among the publications used to write this article, n = 14 were related to the influence of alcohol consumption (clinical studies n = 6, experimental studies n = 8) and n = 40 were related to the influence of smoking (clinical studies n = 33, experimental studies n = 7) on oral redox homeostasis. The reviewed literature indicates that alcohol abusers and smokers are more likely to suffer from salivary gland dysfunction, as well as develop precancerous lesions due to DNA damage. Compared to alcohol abstainers and non-smokers, alcohol drinkers and smokers are also characterized by a deterioration in periodontal health measured by various indicators of periodontal status. In summary, alcohol abuse and smoking are associated with disrupted oral redox homeostasis, which may lead not only to tooth loss, but also contribute to various adverse effects related to mental health, digestive processes and chronic inflammation throughout the human body.

Oxidative stress in alcohol-induced rat parotid sialadenosis

This study evaluated the effect of chronic ethanol consumption on the oxidative status of rat parotid and submandibular glands. To identify the endogenous response to ethanol ingestion, the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined. In addition, the antioxidant alpha-tocopherol was supplied to the animals in order to estimate its action in ethanol-associated glandular damage. The thiobarbituric acid reactive substances (TBARS), and the protein carbonyl (PC) content, both markers of cellular oxidative stress on lipid and protein structures, respectively, were recorded. Animals subjected to alcohol ingestion showed a low body growth rate with concomitant enlargement of absolute and relative parotid wet weight, compared with pair-fed calorie-controlled rats. Parotid glands of ethanol-treated animals showed increased SOD and GPx activity, and alpha-tocopherol was able to reduce their activities to the control levels. TBARS and PC were enhanced after chronic ethanol treatment in rat parotids. Supplemental alpha-tocopherol suppressed the oxidative ethanol-induced damage in lipid without affecting induced protein oxidation. Submandibular glands revealed no alterations in the weight, enzymatic and oxidative parameters tested due to ethanol and/or alpha-tocopherol ingestion. These findings indicate the involvement of oxidative stress in parotid gland sialadenosis due to ethanol consumption and the capability of alpha-tocopherol to halt lipid damage, although this low-molecular antioxidant compound leads to neither increased glandular weight nor protein oxidation in ethanol-induced parotid alterations.

Prostaglandin E2 production by uterine stromal cell line UIII: regulation by estradiol and evidence of an ethanol action

We have recently established a uterine stromal cell line (UIII). The purpose of the present study was to determine whether these cells have retained the ability to produce and release prostaglandins after several passages and whether this production was regulated. UIII cells, grown in basal conditions, released a very low amount (40.6 +/- 2.9 pg/24h/10(6) cells) of prostaglandin E2 (PGE2) though cellular content was more elevated (192 +/- 23 pg/10(6) cells). Ethanol increased the cellular content but decreased the release of PGE2, whereas estradiol 17 beta (E2) increased it in a dose-dependent manner, but had no effect on the cellular content. The PGE2 release by cells grown in medium containing 10 microM arachidonate (AA) reached 1.39 +/- 0.05 ng/24h/10(6) cells, and was further increased to 2.1 +/- 0.1 ng/24 h/10(6) cells by the addition of ethanol. Under the latter condition, E2 was ineffective. This study also showed that UIII cells expressed an immunoreactive pancreatic type 14 kD PLA2. A substantial increased 14 kD PLA2 expression was observed in ethanol-treated cells, suggesting that ethanol-effect on prostaglandin production might be partly mediated by PLA2 increase. Medium supplementation with arachidonate also resulted in a significant increase of intracellular 14 kD PLA2 expression. The present results showed that uterine stromal UIII cells have retained the enzymatic machinery to produce PGE2. Moreover these data demonstrate that ethanol and E2 affect differently uterine PGE2 production.

Expression of prostaglandin E2 receptor in hamster buccal pouch: effect of benzo (a) pyrene and nicotine

Prostaglandin E2 (PGE2) plays an important role in the maintenance of oral mucosal integrity. In this study, we characterized PGE2 receptor binding in the buccal mucosa of Syrian hamster and assessed the effect of nicotine (NC) and benzo (a) pyrene (BP), the two major ingredients in cigarette smoke, on this receptor. Adult male animals were treated for 4 weeks by apical swabbing of the buccal pouch with corn oil (control, C), 1 mM NC, BP, or NC + BP in corn oil, twice a day, 5 days a week. The results obtained with the untreated group revealed the presence of a specific PGE2 receptor consisting of two binding sites (high affinity with Kd = 1.52 nM and Bmax = 37 fmol/mg protein and low affinity with Kd = 813 nM and Bmax = 1.29 pmol/mg protein). The treatment with NC, BP, and NC + BP caused a significant decrease in PGE2 receptor binding (specific binding: 10.20 +/- 0.42, 6.84 +/- 1.32**, 6.58 +/- 0.67** and 5.88 +/- 1.03** fmol/mg protein; C, NC, BP, and NC+BP, respectively; Mean +/- SD, n = 5, **p < 0.01). The data suggest that decreased receptor binding for PGE2 in the buccal mucosa may be the cause for the adverse effect of cigarette smoke on the health of oral mucosa.