Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prevalence of vitamin B-12 deficiency increases with age, probably resulting from malabsorption of food-bound B-12 secondary to gastric atrophy. On the basis of this assumption, the Institute of Medicine (IOM) recommends those aged >50 y consume crystalline vitamin B-12. There is limited information on the prevalence of gastric atrophy in the elderly and whether the IOM recommendation would be effective. The objective of this study was to assess predictors of vitamin B-12 status and their interactions in free-living elderly. Individuals (n = 57) with deficient plasma vitamin B-12 (p-B12 < 148 pmol/L) were compared with 68 individuals with marginal p-B12 (148-221 pmol/L) and 52 with normal p-B12 (>221 pmol/L) in a cross-sectional sample (n = 1546) of elderly (>60 y) Latinos in California. Associations were examined among p-B12 and serum gastrin, vitamin B-12 intake from food and crystalline sources, and medications that putatively affect vitamin B-12 absorption. Serum gastrin was elevated, indicating gastric atrophy, in 48% of participants with deficient p-B12, 23% with marginal p-B12 and 21% of normal p-B12 participants, and was a significant predictor of deficient p-B12 and high plasma homocysteine (p-tHcy). Median total vitamin B-12 intake exceeded recommendations and was similar among status groups. Crystalline vitamin B-12 intake in the normal p-B12 group was higher than in the deficient p-B12 group (P < 0.01), and tended to be higher than the marginal group (P = 0.07). When serum gastrin was elevated, p-B12 was predicted by crystalline vitamin B-12, but not by intake of vitamin B-12 from food. Elevated serum gastrin was highly prevalent and predicted vitamin B-12 depletion. Crystalline vitamin B-12 intake predicted p-B12 in individuals with elevated serum gastrin, supporting IOM recommendations to increase consumption of crystalline vitamin B-12.
 ...
PMID:Plasma vitamin B-12 concentrations in an elderly latino population are predicted by serum gastrin concentrations and crystalline vitamin B-12 intake. 1294 63

A case of peripheral neuropathy in a patient with diabetes who had atypical clinical findings is presented. Because of the atypical initial manifestations and short duration of insulin-dependent diabetes, another cause of the neuropathy was suspected. The presence of vitiligo, hypothyroidism, and diabetes prompted a search for evidence of pernicious anemia. Despite a normal blood cell count, the diagnosis of pernicious anemia was confirmed on the basis of an increased serum gastrin level and antiparietal cell antibody titer. Treatment with vitamin B12 resulted in an arrest, but not a reversal, of the signs of peripheral neuropathy. In patients with diabetes, vitamin B12 deficiency should be suspected; its early diagnosis and treatment are important in minimizing neurologic damage.
 ...
PMID:Nondiabetic neuropathy in a patient with diabetes. 1525 65

Proper absorption of vitamin B12 requires gastric corpus mucosa that functions appropriately and secretes intrinsic factor needed as an essential cofactor for the absorption of dietary vitamin B12 in the small bowel. Here we describe the prevalence of vitamin B12 deficiency and atrophic corpus gastritis (ACG) in patients with coronary heart disease. Fasting serum was obtained from patients who were admitted for cardiovascular diseases at the Coronary Care Unit in Nijmegen, the Netherlands. The status of gastric mucosa was assessed by using the serum levels of pepsinogens I and II, gastrin-17, and Helicobacter pylori IgG antibodies and analyzed over vitamin B12 level subgroups. The study population consisted of 376 patients (mean age, 65 years [SD, 13 years], 227 [60%] males). Low vitamin B12 levels (<150 pM) were detected in 28 patients (7%). Of these 28 patients, 5 (18%) had ACG according to the biomarker assays. Altogether, another 140 patients (37%) had vitamin B12 levels between 150 and 250 pM, of whom 10 (7%) had ACG. Of the remaining patients, five (2%) had ACG. Deficiency of vitamin B12 is common among subjects with coronary heart disease. Up to 20% of these deficiencies are related to ACG.
 ...
PMID:Gastric status and vitamin B12 levels in cardiovascular patients. 1742 27

Proton pump inhibitors (PPIs) have become the mainstay of therapy in acid-related upper gastrointestinal disorders including gastroesophageal reflux disease and peptic ulcer disease. Alltough these medications are generally accepted as safe, the long-term clinical consequences of the inducing hypochlorhydria are not completely clear. Gastric acid production is mainly controlled by the hormone gastrin through a negative feedback in which hypochlorhydria induces an increase in serum gastrin. PPIs have been shown to increase serum gastrin levels. Gastric endocrine cell hyperplasia can occur in 10 to 30% of patients without carcinoid tumors. Recent studies indicate no association between PPI use and the risk of colorectal and gastric cancers. Proton pump inhibitor-associated gastric polyps are totally benign tumors that should not be followed. There is an association between PPIs-induced acid suppression and an increased risk of enteric infection. PPIs do not inhibit intestinal absorption of lipids, iron, phosphorus, magnesium or zinc from food but can affect vitamin B12 status in older patients. Despite the undoubted benefits of PPIs, the practitioner always needs to consider risks and benefits before initiating them.
 ...
PMID:[Risk of long-term treatment with proton pump inhibitors]. 1892 30

A 55-year-old female with a history of psychosis and rheumatoid arthritis was admitted to the hospital for fatigue and dizziness. At admission, macrocytic anemia, high serum lactic acid dehydrogenase (LDH) and gastrin concentrations, decreased serum vitamin B12 concentration, with macroovalocytes and poikilocytes in peripheral blood smear suggested the diagnosis of pernicious anemia. Indirect antiglobulin test (IAT) was negative. Surprisingly, treatment by vitamin B12 and folic acid administered for two weeks was ineffective and followed by transitory worsening of hemoglobin concentration on day 8. Repeat direct antiglobulin test (DAT) and IAT were positive. This immunotransfusion conversion, suggesting the presence of autoimmune hemolytic anemia, could be explained by change in the macroblastic erythrocyte population, i.e. emerging red cells with completely exposed membrane antigens due to vitamin B12 treatment and/or higher degree of dysregulation of the lymphocyte clone secreting erythrocyte autoantibodies. We proposed the coexistence of pernicious and autoimmune hemolytic anemia; therefore, methylprednisolone was added to vitamin B12 treatment. This therapy successfully improved hemoglobin and erythrocyte concentration. Although megaloblastic-pernicious anemia is a common disease, association of pernicious and autoimmune hemolytic anemia with two mechanisms of hemolysis (ineffective erythropoiesis and immune mechanism) is a rare condition, with only several dozens of cases described so far.
 ...
PMID:Combined megaloblastic and immunohemolytic anemia associated--a case report. 1938 72

Gastric exocrine secretion, both acid and non-acid, is required for micronutrients absorption, such as iron, calcium and vitamin B12, drugs absorption, protein digestion. Clinical presentation of a gastric secretion impairment might be then characterized by the presence of both gastrointestinal and non-gastrointestinal specific symptoms (i.e. anemia) or to a non-response to therapies. The main factor that impairs gastric exocrine secretion homeostasis is mucosal chronic inflammation that principally occurs after colonization by Helicobacter pylori (Hp). The extent and distribution of gastritis ultimately determine the clinical outcome linked to differences in gastric acid secretion status, the involvement of gastric body leading to a decrease in gastric exocrine secretion with possible progression to mucosal atrophy towards cancer. A correct clinical strategy in the management of Hp infected patients should be then to early identify body involvement, a diagnosis generally missed in that body biopsies are not routinely performed. The use of gastric serological markers, gastrin and pepsinogens, are helpful in suspecting the presence of mucosal atrophy but their diagnostic accuracy for non-atrophic chronic gastritis topography is not adequate despite a good specificity due to the low sensitivity, of all the available biomarkers. Gastric serology associated to anemia/iron-deficiency screening might nevertheless been helpful in the framing of patients that undergo endoscopy in order to highlight the need of extensive mucosal biopsies sampling.
 ...
PMID:Exocrine gastric secretion and gastritis: pathophysiological and clinical relationships. 2144 37

H. pylori is a gram-negative pathogen, etiologically associated with atrophic and non-atrophic gastritis, peptic ulcer, primary gastric B-cell lymphoma and gastric carcinoma. Several observations demonstrated a correlation between H. pylori and malabsorption of essential nutrients; epidemiological studies have shown an association between H. pylori infection and iron deficiency anemia, while the absorption of some vitamins such as vitamin B12, vitamin A, vitamin C, folic acid and Vitamin E may be affected by the infection. The main mechanism related to malabsorption of this components is the modified intragastric pH (hypo- achlorhydria) due to H. pylori infection. Moreover H. pylori is also able to determine a modification of gastrointestinal hormones by reducing plasma levels of ghrelin and increasing those of leptin and gastrin, thus affecting appetite and promoting the occurrence of dyspeptic symptoms. On the other hand, H. pylori eradication has been shown to improve serum level of iron and vitamin B12, has some effects on Vitamin A and Vitamin E absorption and has a late effects on ghrelin levels. As a consequence of those effects, H. pylori is also associated with childhood malnutrition in developing countries either for the occurrence of malabsorption or for an increased susceptibility to enteric infections caused by hypochlorhydria.
 ...
PMID:Nutritional aspects of Helicobacter pylori infection. 2210 25

Autoimmune gastritis is a silent and highly prevalent disease that only becomes clinically manifested with progression to corpus atrophy and development of iron deficient or B12-deficient (pernicious) anaemia. Autoimmune gastritis is associated with autoimmune thyroiditis and type 1 diabetes mellitus. Corpus atrophy may be complicated by gastric carcinoids and gastric cancer. Laboratory diagnosis of autoimmune gastritis rests on serum biomarkers of antibody to parietal cell H/K ATPase and intrinsic factor and corpus atrophy on serum biomarkers of gastrin and pepsinogen levels. Subjects with asymptomatic parietal cell antibody should be regularly assessed for serum biomarkers for progression to corpus atrophy, development of iron and B12 deficiency anaemia and for associated autoimmune thyroiditis and type 1 diabetes mellitus.
...
PMID:Diagnosis and classification of autoimmune gastritis. 2442 93

Autoimmune polyglandular syndrome by definition consists of two or more endocrinological insufficiencies or two organ specific autoimmune diseases. There are no stringent criteria for endocrinological evaluation of patients with one endocrine insufficiency. However, detailed endocrinological evaluation should be undertaken in patients with two autoimmune diseases. Additionally, follow up thereafter should be a must in these patients in order to avoid the possibility of not diagnosing subsequent autoimmune diseases that can occur. The aim of this case report is to point to the necessity of endocrinological screening to be made in patients presenting with gastric carcinoid type 1. We report on a 62-year-old woman who was diagnosed with primary hypothyroidism in 1993. In 2011, she was re-admitted to the hospital due to increasing fatigue. Macrocytic anemia, low vitamin B12 levels and positive parietal antibodies confirmed pernicious anemia. Furthermore, she underwent gastroscopy, which revealed two polyps in the corpus of the stomach and one in the fornix. Endoscopic mucosal resection was performed and histopathologic analysis confirmed three G1 gastric carcinoids (Ki67 2%). Additional endocrinological evaluation disclosed positive glutamic acid decarboxylase antibodies, but normal fasting and postprandial glucose and HbA1c. In 2013, she was diagnosed with glucose intolerance and subsequently with latent autoimmune diabetes of adulthood. Plasma glucose and HbA1c normalized after dietary intervention. Due to the increase of serum chromogranin A, prophylactic antrectomy was performed in 2014. The patient is still followed-up and has normal chromogranin A, gastrin and HbA1c levels.
 ...
PMID:GASTRIC CARCINOID TYPE 1 IN A PATIENT WITH AUTOIMMUNE POLYGLANDULAR SYNDROME: ADDITIONAL ENDOCRINOLOGICAL EVALUATION REQUIRED. 2701 30

Although the actual prevalence of chronic atrophic gastritis is unknown and it is probable that this entity goes largely underdiagnosed, patients in whom diagnosis is established usually present advanced stages of disease. Destruction of parietal cells, either autoimmune-driven or as a consequence of Helicobacter pylori infection, determines reduction or abolition of acid secretion. Hypo/achloridia causes an increase in serum gastrin levels, with an increased risk of the development of neuroendocrine tumors. Microcytic, hypochromic anemia frequently precedes the development of megaloblastic, vitamin B12-associated anemia. Moreover, vitamin B12 deficiency,may cause elevation of homocysteine, with an increase in the cardiovascular risk, and may be associated with neurological manifestations, mainly characterized by spinal cord demyelination and atrophy, with ensuing sensory-motor abnormalities. Gastrointestinal manifestations seem to be associated with non-acid reflux and tend to be non-specific.
 ...
PMID:Clinical manifestations of chronic atrophic gastritis. 3056 24


<< Previous 1 2 3 4