Publications by authors named "Tepikin A"

The WD40 domain (WDD) of ATG16L1 plays a pivotal role in non-canonical autophagy. This study examined the role of recently identified LAP-like non-canonical autophagy (LNCA) in acute pancreatitis. LNCA involves rapid single-membrane LC3 conjugation to endocytic vacuoles in pancreatic acinar cells.

View Article and Find Full Text PDF

The recent elegant study by Y. Yuan and colleagues examined functional relationships between the lysosomal two-pore channels 2 (TPC2) and IP3 receptors (IP3Rs) located in the endoplasmic reticulum [1]. The findings of this study suggest functional coupling of these channels and receptors.

View Article and Find Full Text PDF

The metastasis of a gynecological malignancy to the Bartholin gland is rare. We report the case of a 62-year-old patient who had undergone extensive treatment of metastatic ovarian cancer that involved the liver, spleen, and peritoneum. She presented with painful swelling of the left vulva.

View Article and Find Full Text PDF

Recent studies have highlighted the importance of autophagy and particularly non-canonical autophagy in the development and progression of acute pancreatitis (a frequent disease with considerable morbidity and significant mortality). An important early event in the development of acute pancreatitis is the intrapancreatic activation of trypsinogen, (i.e.

View Article and Find Full Text PDF

Salivary secretion is important for digestion and paramount for oral health. Both exocytotic secretion of proteins (including salivary amylase and mucins) and fluid secretion contribute to the formation of saliva. A recent study by T.

View Article and Find Full Text PDF

Acute pancreatitis (AP) is a severe and potentially fatal disease caused predominantly by alcohol excess and gallstones, which lacks a specific therapy. The role of Receptor-Interacting Protein Kinase 1 (RIPK1), a key component of programmed necrosis (Necroptosis), is unclear in AP. We assessed the effects of RIPK1 inhibitor Necrostatin-1 (Nec-1) and RIPK1 modification (RIPK1: kinase dead) in bile acid (TLCS-AP), alcoholic (FAEE-AP) and caerulein hyperstimulation (CER-AP) mouse models.

View Article and Find Full Text PDF
Article Synopsis
  • In 2008, guidelines were established for researching autophagy, which has since gained significant interest and new technologies, necessitating regular updates to monitoring methods across various organisms.
  • The new guidelines emphasize selecting appropriate techniques to evaluate autophagy while noting that no single method suits all situations; thus, a combination of methods is encouraged.
  • The document highlights that key proteins involved in autophagy also impact other cellular processes, suggesting genetic studies should focus on multiple autophagy-related genes to fully understand these pathways.
View Article and Find Full Text PDF

Acute pancreatitis is a frequent disease that lacks specific drug treatment. Unravelling the molecular mechanisms of acute pancreatitis is essential for the development of new therapeutics. Several inducers of acute pancreatitis trigger sustained Ca increases in the cytosol and mitochondria of pancreatic acinar cells.

View Article and Find Full Text PDF

Acute pancreatitis (AP) is a debilitating, sometimes fatal disease, marked by local injury and systemic inflammation. Mitochondrial dysfunction is a central feature of pancreatic damage in AP, however, its involvement in circulating blood cell subtypes is unknown. This study compared mitochondrial bioenergetics in circulating leukocytes from AP patients and healthy volunteers: 15 patients with mild to severe AP were compared to 10 healthy controls.

View Article and Find Full Text PDF

Unlabelled: Activation of trypsinogen (formation of trypsin) inside the pancreas is an early pathological event in the development of acute pancreatitis. In our previous studies we identified the activation of trypsinogen within endocytic vacuoles (EVs), cellular organelles that appear in pancreatic acinar cells treated with the inducers of acute pancreatitis. EVs are formed as a result of aberrant compound exocytosis and subsequent internalization of post-exocytic structures.

View Article and Find Full Text PDF

Mitochondrial dysfunction is a core feature of acute pancreatitis, a severe disease in which oxidative stress is elevated. Mitochondrial targeting of antioxidants is a potential therapeutic strategy for this and other diseases, although thus far mixed results have been reported. We investigated the effects of mitochondrial targeting with the antioxidant MitoQ on pancreatic acinar cell bioenergetics, adenosine triphosphate (ATP) production and cell fate, in comparison with the non-antioxidant control decyltriphenylphosphonium bromide (DecylTPP) and general antioxidant -acetylcysteine (NAC).

View Article and Find Full Text PDF

Background And Aims: Cells in pancreatic ductal adenocarcinoma (PDAC) undergo autophagy, but its effects vary with tumor stage and genetic factors. We investigated the consequences of varying levels of the autophagy related 5 (Atg5) protein on pancreatic tumor formation and progression.

Methods: We generated mice that express oncogenic Kras in primary pancreatic cancer cells and have homozygous disruption of Atg5 (A5;Kras) or heterozygous disruption of Atg5 (A5;Kras), and compared them with mice with only oncogenic Kras (controls).

View Article and Find Full Text PDF

Histones are positively charged nuclear proteins that facilitate packaging of DNA into nucleosomes common to all eukaryotic cells. Upon cell injury or cell signalling processes, histones are released passively through cell necrosis or actively from immune cells as part of extracellular traps. Extracellular histones function as microbicidal proteins and are pro-thrombotic, limiting spread of infection or isolating areas of injury to allow for immune cell infiltration, clearance of infection and initiation of tissue regeneration and repair.

View Article and Find Full Text PDF

FF-ATP synthase inhibitory factor 1 (IF1) inhibits the reverse mode of FF-ATP synthase, and therefore protects cellular ATP content at the expense of accelerated loss of mitochondrial membrane potential (ΔΨm). There is considerable variability in IF1 expression and its influence on bioenergetics between different cell types. High levels of IF1 in a number of cancers have been linked to increased glycolysis, resistance to cell death, increased migration and proliferation.

View Article and Find Full Text PDF

Cellular organelles form multiple junctional complexes with one another and the emerging research area dealing with such structures and their functions is undergoing explosive growth. A new research journal named "Contact" has been recently established to facilitate the development of this research field. The current consensus is to define an organellar junction by the maximal distance between the participating organelles; and the gap of 30 nm or less is considered appropriate for classifying such structures as junctions or membrane contact sites.

View Article and Find Full Text PDF

Key Points: Giant trypsin-containing endocytic vacuoles are formed in pancreatic acinar cells stimulated with inducers of acute pancreatitis. F-actin envelops endocytic vacuoles and regulates their properties. Endocytic vacuoles can rupture and release their content into the cytosol of acinar cells.

View Article and Find Full Text PDF

Mitochondrial dysfunction lies at the core of acute pancreatitis (AP). Diverse AP stimuli induce Ca-dependent formation of the mitochondrial permeability transition pore (MPTP), a solute channel modulated by cyclophilin D (CypD), the formation of which causes ATP depletion and necrosis. Oxidative stress reportedly triggers MPTP formation and is elevated in clinical AP, but how reactive oxygen species influence cell death is unclear.

View Article and Find Full Text PDF

Objectives: Mitochondrial permeability transition pore inhibition is a promising approach to treat acute pancreatitis (AP). We sought to determine (i) the effects of the mitochondrial permeability transition pore inhibitor 3,5-seco-4-nor-cholestan-5-one oxime-3-ol (TRO40303) on murine and human pancreatic acinar cell (PAC) injury induced by fatty acid ethyl esters (FAEEs) or taurolithocholic acid-3-sulfate and (ii) TRO40303 pharmacokinetics and efficacy in experimental alcoholic AP (FAEE-AP).

Methods: Changes in mitochondrial membrane potential (Δψm), cytosolic Ca ([Ca]c), and cell fate were examined in freshly isolated murine or human PACs by confocal microscopy.

View Article and Find Full Text PDF

Background: Clinical and experimental acute pancreatitis feature histone release within the pancreas from innate immune cells and acinar cell necrosis. In this study, we aimed to detail the source of circulating histones and assess their role in the pathogenesis of acute pancreatitis.

Methods: Circulating nucleosomes were measured in patient plasma, taken within 24 and 48 h of onset of acute pancreatitis and correlated with clinical outcomes.

View Article and Find Full Text PDF

The junctions between the endoplasmic reticulum and the plasma membrane are essential platforms for the activation of store-operated Ca influx. These junctions have specific dimensions and are nonuniformly distributed in polarized cells. The mechanisms involved in the formation of the junctions are currently undergoing vigorous investigation, and significant progress was attained in this research area during the last 10 years.

View Article and Find Full Text PDF
Introduction.

Adv Exp Med Biol

December 2017

In the title of this part of the book, the tail is wagging not just in a single dog but multiple dogs; in other words, a single process SOCE (tail) somehow involves a cross talk of (wagging) large and powerful organelle and cellular compartments (dogs). So how is this possible? Is this really necessary? Is the title actually appropriate?SOCE is a rather special process, it allows efficient signaling based on a ubiquitous second messenger (Ca) in multiple cell and tissue types, it has specific signaling modality (i.e.

View Article and Find Full Text PDF

Objectives: To evaluate the therapeutic potential of I-BET-762, an inhibitor of the bromodomain and extra-terminal (BET) protein family, in experimental acute pancreatitis (AP).

Methods: AP was induced by retrograde infusion of taurolithocholic acid sulphate into the biliopancreatic duct (TLCS-AP) or 2 intraperitoneal (i.p.

View Article and Find Full Text PDF

Mitochondrial Ca(2+) entry is an important process regulating cellular bioenergetics, redox responses, and apoptosis. The study by Vais and colleagues (Vais et al., 2016), recently published in Cell Reports, describes a novel mechanism of modulating Ca(2+) entry that involves mitochondrial matrix Ca(2+).

View Article and Find Full Text PDF

Endoplasmic reticulum (ER)-plasma membrane (PM) junctions are contact sites between the ER and the PM; the distance between the two organelles in the junctions is below 40 nm and the membranes are connected by protein tethers. A number of molecular tools and technical approaches have been recently developed to visualise, modify and characterise properties of ER-PM junctions. The junctions serve as the platforms for lipid exchange between the organelles and for cell signalling, notably Ca(2+) and cAMP signalling.

View Article and Find Full Text PDF