Pepsinogen

Gastroprotective activity of hydroalcoholic extract of the leaves of Urera baccifera in rodents

ETHNOPHARMACOLOGICAL IMPORTANCE

The species Urera baccifera (L.) Gaudich. ex Wedd. (Urticaceae) is native to the Americas and is distributed widely throughout Brazil, where it is known as urtiga-brava, urtiga-vermelha, or urtigão. The leaves are often used as anti-inflammatory and antirheumatic agents and for the treatment of gastric disorders. However, the pharmacological mode of action underlying the gastroprotection induced by this species has not been investigated.

AIM OF THE STUDY

To contribute to the knowledge of the gastroprotective mode of action of the hydroalcoholic extract of U. baccifera (HEU) leaves.

MATERIALS AND METHODS

Antiulcerogenic effect of HEU against ethanol-induced acute gastric ulcer was evaluated in rats and mice at doses of 3-300 mg/kg. NO-synthase inhibitor (L-NAME), SH blocker (NEM), cyclooxygenase inhibitor (indomethacin) and alpha 2-adrenergic receptor antagonist yohimbine were used to evaluate the participation of cytoprotective factors in HEU gastroprotection. Moreover, the levels of reduced gluthatione (GSH) and cytokines (TNF, IL-6, IL4 and IL-10), as well as the enzymatic activity of gluthatione S-transferase (GST), myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) were measure. Moreover, the samples were analyzed histologically and the antisecretory capability of HEU were quantified using pylorus ligated rats.

RESULTS

The phytochemical analysis of HEU (UPLC/ESI-IT-MS) identified the flavonoids diosmetin and apigenin glucuronide. Furthermore, HEU decreased the occurrence of ethanol-induced ulcers at 30 and 300 mg/kg by 57% and 66%, respectively, compared with the vehicle. The gastroprotective effects were accompanied by increased GSH levels and GST and SOD activity as well as by reduced MPO activity in vivo and in vitro, revealing antioxidant effects and inhibition of neutrophil infiltration. The beneficial effects of 30 and 300 mg/kg HEU were also observed upon histological analyses. Regarding the mode of action, the gastroprotective effect of HEU was abolished by the pre-administration of L-NAME, NEM, indomethacin or yohimbine. Moreover, HEU was able to decrease the IL-6, IL-4 and IL-10 in ulcerated tissue, as well as the pepsin activity of the gastric juice in pylorus-ligated rats.

CONCLUSION

Together, the results confirmed that the gastroprotection elicited by HEU was due reduction in oxidative damage, neutrophil migration, and peptic activity. This work validates the popular use of U. baccifera to treat gastric disorders and supports important future research for the identification of gastroprotective molecules from this species.

Meal-Time Supplementation with Betaine HCl for Functional Hypochlorhydria: What is the Evidence?

It is well established that the inadequate intake of key nutrients can lead to nutrient deficiency-related phenomena. However, even when the intake of nutrients is sufficient, the inadequate digestion and/or absorption of macronutrients, micronutrients or other therapeutic compounds from the diet (i.e., phytonutrients) can result in similar clinical consequences. These consequences include classic GI-related symptoms related to malabsorption, as well as a broad range of clinical and subclinical signs and symptoms (though many nutrient insufficiencies are difficult to diagnose). Along with food matrix issues, the integrative and functional medicine community has long considered inadequate levels of stomach acid, pancreatic enzymes and/or bile acid secretion to greatly contribute to an individual's risk for maldigestion or malabsorption.

Biomarkers in the diagnosis of aspiration syndromes

Recognizing and managing the different types of aspiration events remain a challenging task due to the lack of distinguishing clinical or laboratory characteristics. Numerous biomarkers in serum, sputum and bronchoalveolar lavage have been studied, and their role in the recognition of aspiration remains controversial at this time. Recent animal investigations using an array of biomarkers based on distinct pathogenic features of each aspiration event have produced promising results; however, they have not been validated in humans. Newer markers are being introduced as diagnostic and prognostic tools in conditions such as community-acquired pneumonia and sepsis, but they have not been examined in aspiration. The present review summarizes the different biomarkers that have been studied in aspiration and those who might have a potential clinical use in the future.

The effects of excretions/secretions of Ostertagia circumcincta on ovine abomasal tissues in vitro

Products excreted/secreted by Ostertagia circumcincta stimulated the in vitro release of pepsinogen from intact abomasal mucosal sheets and caused the contraction of strips of abomasal smooth muscle, also in vitro. However, responses occurred only when tissues had been derived from animals that were assumed to have experienced prior exposure to the parasite. The overall median responses for pepsinogen secretion in response to ES, expressed as the ratio of stimulated secretion to basal secretion, were 1.8 for previously exposed animals and 0.9 for parasite-naive animals. For the smooth muscle from the previously exposed animals, the overall median response to ES, expressed as a percentage of the maximal response to carbachol in the same tissues, was 27.0. No responses were seen in muscle from any parasite-naive animal. These results suggest that the responses obtained were hypersensitivity reactions to antigens released by the worms during in vitro culture, and occurring in tissues from animals sensitised by exposure to O. circumcincta in the natural environment.

Magnesium hydrogen breath test using end expiratory sampling to assess achlorhydria in pernicious anaemia patients

A modified magnesium hydrogen breath test, using end expiratory breath sampling, is described to investigate achlorhydria. The efficacy of this test in the diagnostic investigation of pernicious anaemia was compared with that of serum pepsinogen I. Twenty one patients with pernicious anaemia--that is, patients with achlorhydria--and 22 with healed duodenal ulcer and normal chlorhydria were studied. Magnesium hydrogen breath test, serum pepsinogen I, serum gastrin, and standard gastric acid secretory tests were performed in all subjects. The mean (SEM) hydrogen peak value was lower in patients with pernicious anaemia than in the duodenal ulcer group (21.7 (1.9) v 71.3 (5.2) ppm; p = 0.00005). The hydrogen peak value had a 95.2% sensitivity and a 100% specificity to detect pentagastrin resistant achlorhydria. Mean serum pepsinogen I concentrations were also significantly lower in patients with pernicious anaemia than in the duodenal ulcer group (10.7 (2.7) v 123.6 (11.8) micrograms/l p = 0.00005). Sensitivity and specificity to detect pernicious anaemia were both 100% for pepsinogen I. It is concluded that this modified magnesium hydrogen breath test is a simple, noninvasive, cost effective, and accurate method to assess achlorhydria and may be useful in the diagnostic investigation of patients with suspected pernicious anaemia.

Serum pepsinogen I levels in patients with non-ulcer dyspepsia

In order to understand whether the serum pepsinogen I (PGI) levels of non-ulcer dyspepsia (NUD) patients differed from those of healthy controls and which kinds of factors might influence these levels of the former, serum PGI levels were determined by radio-immunoassay in 120 healthy controls and 361 NUD patients. The mean serum PGI level was significantly lower in NUD patients than in the controls (75.8 +/- 38.2 ng/mL versus 95.9 +/- 39.3 ng/mL; P less than 0.0001); in NUD patients, it was significantly higher in males than in females (79.6 +/- 40.4 ng/mL versus 63.2 +/- 26.4 ng/mL; P less than 0.001). However, corrected serum PGI levels according to the lean body mass disclosed no sex difference. Nevertheless, there was a weak correlation between the ages of patients and serum PGI levels (r = 0.403). The serum PGI levels in blood groups A, B, AB and O did not differ significantly. Smoking might be a decisive factor, for the mean serum PGI level was significantly higher among the smokers than among the non-smokers (86.7 +/- 44.6 ng/mL versus 70.6 +/- 33.7 ng/mL; P less than 0.001). It is concluded that the mean serum PGI level of NUD patients, while affected by sex, age, smoker status and the body size, is lower than that of the healthy controls. Without endoscopy, assay of serum PGI level has no place in the diagnosis of dyspepsia because of the wide overlapping of serum PGI levels between NUD patients and patients with other common gastric lesions.

Differential distribution of pepsinogen II between the zones of the human prostate and the seminal vesicle

Pepsinogen II (PG II) is a gastric proenzyme which has previously been found in both human seminal fluid and the prostate gland. However, no regional distribution of PG II has been noted within the prostate nor has it been found in the seminal vesicle. Bouins-fixed sections of central zone, peripheral zone and seminal vesicle, taken from 10 prostates removed at radical prostatectomy or cystectomy, were exposed to antibody against PG II and stained using the A-B-C immunoperoxidase technique. Formalin-fixed tissue from autopsy prostates of four men in the third decade, and six cases with BPH nodules, were also examined for PG II activity. In nine of 10 seminal vesicles, and seven of 10 central zone samples, more than 50 per cent of the cells stained positive for PG II. By contrast, in nine of 10 peripheral zone samples staining was present in five per cent or less of the epithelial cells. Similarly, PG II activity in the four autopsy prostates occurred almost entirely within the central zone and ended abruptly at the boundary between the peripheral and central zones. BPH nodules contained no PG II activity. These findings provide the first evidence that the central and peripheral zones may serve different biological functions. Embryologically it is currently thought that the prostate is of endodermal origin and the seminal vesicle of mesodermal origin. The presence of large amounts of PG II in both the seminal vesicle and central zone lends support to the hypothesis of a common mesodermal origin for these two structures.