Am J Physiol Gastrointest Liver Physiol
November 2022
It has previously been shown that current smoking is protective against endoscopic retrograde cholangiopancreatography (ERCP)-induced acute pancreatitis, but the mechanism of this effect was not identified. We tested the hypothesis that nicotine is the active factor in this protection in a mouse model of ERCP. Pretreatment with nicotine dose dependently inhibited acute pancreatitis caused by infusion of ERCP contrast solution into the main pancreatic duct in mice.
View Article and Find Full Text PDFPancreatic fibrosis is a complication of chronic pancreatitis and is a prominent feature of pancreatic cancer. Pancreatic fibrosis is commonly observed in patients with prolonged pancreatic duct obstruction, which elevates intrapancreatic pressure. We show here that increased pancreatic duct pressure causes fibrosis and describes the mechanism by which pressure increases deposition of extracellular matrix proteins and fibrosis.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
June 2022
Proper mitochondrial function and adequate cellular ATP are necessary for normal pancreatic protein synthesis and sorting, maintenance of intracellular organelles and enzyme secretion. Inorganic phosphate is required for generating ATP and its limited availability may lead to reduced ATP production causing impaired Ca handling, defective autophagy, zymogen activation, and necrosis, which are all features of acute pancreatitis. We hypothesized that reduced dietary phosphate leads to hypophosphatemia and exacerbates pancreatitis severity of multiple causes.
View Article and Find Full Text PDFBackground & Aims: Heavy alcohol consumption is a common cause of acute pancreatitis; however, alcohol abuse does not always result in clinical pancreatitis. As a consequence, the factors responsible for alcohol-induced pancreatitis are not well understood. In experimental animals, it has been difficult to produce pancreatitis with alcohol.
View Article and Find Full Text PDFElevated pressure in the pancreatic gland is the central cause of pancreatitis following abdominal trauma, surgery, endoscopic retrograde cholangiopancreatography, and gallstones. In the pancreas, excessive intracellular calcium causes mitochondrial dysfunction, premature zymogen activation, and necrosis, ultimately leading to pancreatitis. Although stimulation of the mechanically activated, calcium-permeable ion channel Piezo1 in the pancreatic acinar cell is the initial step in pressure-induced pancreatitis, activation of Piezo1 produces only transient elevation in intracellular calcium that is insufficient to cause pancreatitis.
View Article and Find Full Text PDFFamily caregivers can benefit from education-based wellness programs, but many face barriers to attending such programs. The purpose of this research was to explore telehealth as a delivery format for an education-based caregiver wellness program. This qualitative research examined the caregiver experience of a specific program called Powerful Tools for Caregivers (PTC).
View Article and Find Full Text PDFMerely touching the pancreas can lead to premature zymogen activation and pancreatitis but the mechanism is not completely understood. Here we demonstrate that pancreatic acinar cells express the mechanoreceptor Piezo1 and application of pressure within the gland produces pancreatitis. To determine if this effect is through Piezo1 activation, we induce pancreatitis by intrapancreatic duct instillation of the Piezo1 agonist Yoda1.
View Article and Find Full Text PDFGastroenterol Res Pract
April 2017
toxin A is a colonic inflammatory agent that acts partially by activation of TRPV1 (transient receptor potential vanilloid type 1). Resiniferatoxin (RTX) is an excitotoxin that activates TRPV1 at low concentrations and defunctionalizes TRPV1 at high concentrations. RTX at various doses was injected intraluminally into isolated ileal segments in anesthetized rats.
View Article and Find Full Text PDFOutcome of primary and incisional hernia repair is still affected by clinical complications in terms of recurrences, pain and discomfort. Factors like surgical approach, prosthesis characteristics and method of fixation might influence the outcome. We evaluated in a prospective observational study a cohort population which underwent primary and incisional laparoscopic hernia repair, with the use of a composite mesh in polypropylene fixed with absorbable devices.
View Article and Find Full Text PDFInt J Inflam
February 2016
Nicotine is protective in ulcerative colitis but not Crohn's disease of the small intestine, but little is known about the effects of nicotine on Clostridium difficile toxin A-induced enteritis. Isolated ileal or colonic segments in anesthetized rats were pretreated with nicotine bitartrate or other pharmacological agents before intraluminal injection of toxin A. After 3 hours, the treated segments were removed and inflammation was assessed.
View Article and Find Full Text PDFWikipedia is a huge global repository of human knowledge that can be leveraged to investigate interwinements between cultures. With this aim, we apply methods of Markov chains and Google matrix for the analysis of the hyperlink networks of 24 Wikipedia language editions, and rank all their articles by PageRank, 2DRank and CheiRank algorithms. Using automatic extraction of people names, we obtain the top 100 historical figures, for each edition and for each algorithm.
View Article and Find Full Text PDFCell Mol Gastroenterol Hepatol
January 2015
Background & Aims: In the pancreas, activation of primary sensory nerves through the transient receptor potential ion channel TRPV1 contributes to the early stages of development of pancreatitis. Little is known about the mechanism by which this occurs. We investigated whether leukotriene B (LTB) is an endogenous agonist of TRPV1 and mediates pancreatitis.
View Article and Find Full Text PDFBackground: Regular gall bladder contraction reduces bile stasis and prevents gallstone formation. Intraduodenal administration of exogenous pancreatic secretory trypsin inhibitor-I (PSTI-I, also known as monitor peptide) causes cholecystokinin (CCK) secretion.
Design: We proposed that stimulation of CCK release by PSTI would produce gall bladder contraction and prevent gallstones in mice fed a lithogenic diet.
We tested the hypothesis that 5-aminosalicylic acid (5-ASA) inhibits toxin A-induced generation of colonic leukotriene B4 (LTB4) and toxin A colitis in rats. Isolated colonic segments in anesthetized rats were treated intraluminally with toxin A for 3 hours with or without 30 minutes of pretreatment with either 5-ASA or sulfapyridine and then colonic tissue levels of LTB4 were measured and inflammation was assessed. Separately, sulfasalazine was administered to rats in their drinking water for 5 days, isolated colonic segments were then prepared, toxin A was administered, and inflammation was assessed as before.
View Article and Find Full Text PDFAlcohol abuse is a major cause of pancreatitis in people, but the mechanism is unknown. It has been recently demonstrated that transient receptor potential vanilloid 1 (TRPV1) activation causes neurogenic inflammation and plays an important role in acute pancreatitis. Moreover, TRPV1 is activated by ethanol.
View Article and Find Full Text PDFCholecystokinin (CCK) is a satiety hormone produced by discrete enteroendocrine cells scattered among absorptive cells of the small intestine. CCK is released into blood following a meal; however, the mechanisms inducing hormone secretion are largely unknown. Ingested fat is the major stimulant of CCK secretion.
View Article and Find Full Text PDFObjectives: We tested the hypothesis that leukotriene B4 (LTB4) mediates pancreatic inflammation in rats via activation of the transient receptor potential vanilloid 1 (TRPV1).
Methods: Leukotriene B4 or a vehicle was administered to adult rats via celiac axis injection after pretreatment with the TRPV1 antagonist, capsazepine, or vehicle, and the severity of subsequent pancreatitis was assessed by measuring pancreatic edema, myeloperoxidase (MPO) activity, and histological grading. In a second experiment, acute pancreatitis was induced by common pancreaticobiliary duct ligation.
Background: Urinary and sexual dysfunctions are frequent after surgery for rectal cancer. Total mesorectal excision (TME) improves local recurrence and survival rates, and does not hamper recognition and sparing of hypogastric and pelvic splanchnic nerves. It is not known how laparoscopic rectal resection could change functional complication rates.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
April 2011
Cholecystokinin (CCK) is produced by discrete endocrine cells in the proximal small intestine and is released following the ingestion of food. CCK is the primary hormone responsible for gallbladder contraction and has potent effects on pancreatic secretion, gastric emptying, and satiety. In addition to fats, digested proteins and aromatic amino acids are major stimulants of CCK release.
View Article and Find Full Text PDFThe peptide tyrosine tyrosine (PYY) is produced and secreted from L cells of the gastrointestinal mucosa. To study the anatomy and function of PYY-secreting L cells, we developed a transgenic PYY-green fluorescent protein mouse model. PYY-containing cells exhibited green fluorescence under UV light and were immunoreactive to antibodies against PYY and GLP-1 (glucagon-like peptide-1, an incretin hormone also secreted by L cells).
View Article and Find Full Text PDFAim: Histology quality assurance is crucial for screening programmes and can be performed by circulating glass slides, which has certain intrinsic disadvantages. The present study aimed to assess the accuracy of virtual microscopy in terms of reliability and diagnostic reproducibility in colorectal cancer screening programmes.
Methods: 457 consecutive lesions detected in people undergoing colonoscopy were examined histologically in two pathology units, using both traditional optical microscopy and virtual microscopy (6-12 months later).
Cholecystokinin (CCK) is secreted by neuroendocrine cells comprising 0.1%-0.5% of the mucosal cells in the upper small intestine.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
April 2010
Endogenous trypsin inhibitors are synthesized, stored, and secreted by pancreatic acinar cells. It is believed that they play a protective role in the pancreas by inhibiting trypsin within the cell should trypsinogen become prematurely activated. Rodent trypsin inhibitors are highly homologous to human serine protease inhibitor Kazal-type 1 (SPINK1).
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