Pancreatic Acini Research Articles

Cadmium-induced pancreatic toxicity in rats: comparing vitamin C and Nigella sativa as protective agents: a histomorphometric and ultrastructural study

The study aimed to assess the toxic effect of cadmium (Cd) on the exocrine and endocrine functions of pancreas, the changes in pancreatic tissue after Cd withdrawal, and the protective effects of vitamin C (VC) and Nigella sativa (NS) against Cd-induced damage. Rats were assigned to: control, Cd-treated (0.5 mg/kg/d intraperitoneal [IP] injection), VC and Cd-treated (receiving 100 mg/kg/d VC orally and Cd concomitantly), NS and Cd-treated (receiving 20 mg/kg/d NS and Cd, simultaneously), and Cd withdrawal (receiving Cd for 30 d then living free for recovery for other 30 d). Blood samples were collected and post-sacrifice pancreatic specimens were processed for light and electron microscope study. Quantitative analyses of pancreatic collagen area%, pancreatic islet parameters, β cell density, and insulin immunoexpression were done. Fasting blood glucose was significantly increased in Cd-treated and Cd-withdrawal groups, while co-treatment with VC and NS caused significant reductions (p < 0.05). Cd-induced extensive degenerative changes in pancreatic acini and islets at light and ultrastructure levels. Obvious fibrosis and congestion of blood vessels were noticed. Significant reductions in pancreatic islet number, volume, and surface area and diminished beta cell count and insulin immunoexpression were observed. After withdrawal of Cd, the whole pancreatic tissue still showed a serious impact. Concomitant treatment with VC or NS obviously reduced these degenerative changes and significantly improved pancreatic islet parameters and insulin immunoexpression. VC showed a better amendment than NS, but this difference was statistically insignificant. Therefore, VC and NS could be used as prophylactic agents that lessen Cd consequences on the pancreas.

The Effect of Aqueous Extract of Fenugreek Plant on the Pancreas in Rabbits Induced with Diabetes and the Histological Changes Occurring in Them

The study aimed to induce alloxan-induced diabetes in local white rabbits, study its effect on the pancreas, treat them with aqueous extract of fenugreek at a concentration of 200 mg/kg orally, and observe the histological changes. To complete the study 20 white rabbits were taken and divided into three groups; 1st group is the control group and this group was dosed with distilled water. 2nd group was treated with Alloxan and was injected intraperitoneally at a dose of 175 mg/kg. 3rd group is the group that was treated with the aqueous extract of fenugreek at a concentration of 200 mg/kg for 30 days. After the end of the injection and dosing period after 30 days, the animals were killed and the pancreas was removed to perform histological techniques on them. its the group treated with alloxan was observed that the pancreas was composed of exocrine glandular lobules with enlarged secretory cells within the pancreatic acinus, with the presence of pale nuclei lacking pigment. Also, blood congestion of the blood vessels was found between the lobules of the gland and the pancreatic gland showed hyperplasia of its glandular epithelial cells with nuclei devoid of pigment due to the loss of the basal pigment in them. Blood congestion of the blood vessels appeared in the gland between the lobules, and dense colloidal fibers appeared in them and contained fibroblasts and phagocytic cells and the group treated with the aqueous extract of the fenugreek plant :The pancreatic parenchyma contained normal exocrine glandular secretion units, where the cytoplasm and nuclei of these cells were located in the form of regular axes, septations between the lobules of the pancreas surrounded by thick-walled arteries containing blood. and the islets of Lankerhans appeared between the yeast-secreting lobules of the pancreas. They contained endocrine cells of alpha and beta cells surrounded by blood sinusoids. The interstitial tissue between the lobules is composed of loose connective tissue containing colloidal fibers the pancreatic tissue contained the serous secretory vasculature of yeasts, which were uniform in shape, and between them were found blood vessels excessive with blood, where blood was found in a decomposed form in them, with the presence of small channels inside the lobules that transport yeasts.

Antidiabetic Effects of Foeniculum vulgare in Alloxan-induced Diabetic Male Rats

Background &amp; objective: Diabetes mellitus (DM) has become one of the most challenging health problems of the 21st century. Foeniculum vulgare (Mouri in Bengali), an ancient culinary herb, is known to reduce blood glucose levels thus reducing the risk of diabetes. This study was done to observe the antidiabetic role of Mouri in alloxan-induced diabetic male rats. Methods: This experimental study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC), Dhaka from July 2018 to June 2019. A total of 30 healthy Wistar albino male rats, 90-120 days old, weighing between 150-180g were included in the study. After acclimatization for 14 days, they were divided into two groups: the control group (Group A) and the experimental group (Group B – diabetic rats treated with Mouri). The control group was again subdivided into Group A1 (normal control group) and Group A2 (alloxan-induced diabetic control group). Each of these groups consisted of 10 rats. All the rats received a basal diet for 21 days. In addition to the basal diet, Group A2 and Group B received a single intraperitoneal injection of alloxan 140 mg/kg on day 1 to induce diabetes. Moreover, Group B received Mouri extract 150 mg/kg/day orally for 21 consecutive days starting from day 1 of the study period. After 12 hours of fasting, blood samples were collected from the tail veins of every rat on day 1 for estimation of Fasting Blood Glucose (FBG) and serum ALT levels. On day 4 FBG levels of all the rats were measured once again. Then all the rats were sacrificed on day 22 and their blood samples were collected from the heart. The outcome variables, such as FBG level, serum levels of insulin, were measured and compared among the study groups. The pancreatic tissue was also collected and histopathology was done by standard laboratory procedure to study their histologic architecture. Result: In this study, fasting blood glucose level in diabetic rats treated with Mouri at the endpoint of the study (on day 22) was significantly lower (5.51 ± 0.47 mmol/L) than that in alloxan-induced diabetic control (13.52 ± 0.76 mmol/L) (p &lt; 0.001) and was almost equal to that in normal control (5.38 ± 0.55 mmol/L) (p = 0.891). The serum insulin level in diabetic rats treated with Mouri (11.52 ± 0.84 mmol/L) was almost similar to that of normal control (12.46 ± 1.07 mmol/L) on day 22, whereas it was much higher than that in alloxan-induced diabetic control (8.51 ± 0.68 mmol/L) (p &lt; 0.001). Histological study of pancreases of the rats, revealed extravasation of blood in the pancreatic acini, reduced area of islets of Langerhans with atrophy, vacuolation, degeneration, and pyknosis of β-cell nuclei and centrilobular necrosis in the alloxan-induced diabetic control rats. Conclusion: Mouri (Foeniculum vulgare) improves the glycemic status of the alloxan-induced diabetic rats. Ibrahim Card Med J 2023; 13 (1&amp;2): 53-59

Ameliorating effect of nutmeg (Myristica fragrans) on the pancreas of alloxan-induced diabetic rats

Objective: This research work was carried out to investigate the effect of Nutmeg on the histology of pancreas of alloxan-induced diabetic rats. Methodology: Twenty-five Wistar rats weighing 150 g – 180 g were purchased and acclimatized for two weeks. Thereafter, they were divided into five groups designated as A – E with five rats each. Group A serve as the control group, while groups B – C served as the experimental group, and were induced with alloxan. Group A received distilled water only, while groups B – C received Glucophage, 400 mg/kg of Nutmeg and 800 mg/kg of Nutmeg daily for 21 days through orogastric tube. On the 22nd day, the animals were sacrificed via chloroform inhalation, and pancreas were harvested from the rats for histological study. Results: Histopathological findings revealed normal well perfused pancreatic tissue with active Islets of Langerhans (IL), pancreatic acini (PA) and well out-lined acini cells (AC); poorly perfused pancreatic tissue with severe focal areas of Islets of the Langerhans atrophy and severe dissolution of acini; moderate necrotic (N) and pale appearance of the pancreatic acini in R1 however the Islets of the Langerhans in both sections are moderately normal; mild necrotic (N) and pale appearance of the pancreatic acini with mild aggregation of inflammatory cells (AIC); and mild aggregation of inflammatory cells (AIC) with active Islets of the Langerhans (IL) respectively for groups A – E. Conclusion: Nutmeg extract has ameliorating effect on the histology of the pancreas of alloxan-induced rats which improves with increase in the dosages of the extract.

Screening of Amino Acids as a Safe Energy Source for Isolated Rat Pancreatic Acini.

Amino acids play an essential role in protein synthesis, metabolism, and survival of pancreatic acini. Adequate nutritional support is important for acute pancreatitis treatment. However, high concentrations of arginine and lysine may induce acute pancreatitis. The study aimed to identify the most suitable l -amino acids as safe energy sources for pancreatic acinar cells. Pancreatic acini were isolated from male Wistar rats. Effects of amino acids (0.1-20 mM) on uncoupled respiration of isolated acini were studied with a Clark electrode. Cell death was evaluated with fluorescent microscopy and DNA gel electrophoresis. Among the tested amino acids, glutamate, glutamine, alanine, lysine, and aspartate were able to stimulate the uncoupled respiration rate of isolated pancreatic acini, whereas arginine, histidine, and asparagine were not. Lysine, arginine, and glutamine (20 mM) caused complete loss of plasma membrane integrity of acinar cells after 24 hours of incubation. Glutamine also caused early (2-4 hours) cell swelling and blebbing. Aspartate, asparagine, and glutamate only moderately decreased the number of viable cells, whereas alanine and histidine were not toxic. DNA fragmentation assay and microscopic analysis of nuclei showed no evidence of apoptosis in cells treated with amino acids. Alanine and glutamate are safe and effective energy sources for mitochondria of pancreatic acinar cells.

Cholecystokinin 1 Receptor Is Activated Permanently in Photodynamic Action

In contrast to agonist activation that is reversed after washout of agonist, we have found that cholecystokinin 1 receptor (CCK1R) is activated permanently by singlet oxygen in type II photodynamic action, the G Protein Coupled Receptor (GPCR) Activated By Singlet Oxygen is named GPCR-ABSO. CCK1R ectopically expressed in cell lines is activated in photodynamic action with photosensitizer sulphonated aluminum phthalocyanine (SALPC) or with genetically encoded protein photosensitizers (such as miniSOG, KillerRed) to trigger persistent calcium oscillations which are not washed out. Such permanent photodynamic CCK1R activation is seen also in freshly isolated pancreatic acini, which is inhibited by CCK1R antagonist. Photodynamic CCK1R activation is physiological in intensity, triggering calcium oscillations similar in frequencies to those induced by physiological CCK concentrations (10 - 100 pM). The molecular mechanisms for such permanent photodynamic activation of CCK1R at the physiological level are three-fold. When membrane proteins prepared from isolated rat pancreatic acini are subject to Western blot, CCK1R is found to be present as both dimers and monomers. After photodynamic action with SALPC at an intensity that would trigger persistent calcium oscillations in live cells, the resting receptor dimer is converted quantitatively to monomer, similar to agonist stimulated CCK1R monomerization revealed by bioluminescence resonance energy transfer (BRET) method in rat CCK1R-expressing COS cells, suggesting that photodynamic CCK1R activation we have demonstrated is likely quite physiological. Whilst CCK1R is activated by singlet oxygen in photodynamic action, the M3 acetylcholine receptor is not affected. However, when TM3 of CCK1R is transplanted to M3R to replace TM3 of M3R, the chimeric receptor M3R-TM3CCK1R becomes activatable in photodynamic action, after tagging with miniSOG. The calculated extent of miniSOG photodynamic activation of M3R, chimeric M3R-TM3CCK1R, and CCK1R are 0%, 65%, 100% respectively. Comparative studies with pancreatic acini isolated from the rat, mouse and Peking duck found that sensitivity for photodynamic CCK1R activation is, in descending order: mouse &gt; rat &gt; Peking duck, the same order of the size of structure-free region of intracellular loop 3 (ICL3). Other than CCK1R, CCK2R is photodynamically activated also, after tagging with protein photosensitizer miniSOG. CCK1R and CCK2R are known to be involved in vital physiological functions: pancreatic secretion, satiety sensation, sinoatrial node pace-making, memory formation and storage, and others. Our work implies that all these and other physiological functions might be modulated in vivo by photodynamic CCK1R activation. The fact that such property of permanent photodynamic activation could be transplanted from CCK1R to other GPCR such as M3R suggests that photodynamic activation of GPCR could be used to tease apart the roles and functions of vast numbers of GPCR. Other functional proteins such as NAD(P)H oxidase 2, BK/Slo channel, CaMKII, riboflavin transporter (SLC52A1/RFVT1), might also be photodynamically activated permanently. This work was supported by The Natural Science Foundation of China (NSFC, Grant Nos. 31971170 and 32271278). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Cytokine CCL9 Mediates Oncogenic KRAS-Induced Pancreatic Acinar-to-Ductal Metaplasia by Promoting Reactive Oxygen Species and Metalloproteinases.

Pancreatic ductal adenocarcinoma (PDAC) can originate from acinar-to-ductal metaplasia (ADM). Pancreatic acini harboring oncogenic Kras mutations are transdifferentiated to a duct-like phenotype that further progresses to become pancreatic intraepithelial neoplasia (PanIN) lesions, giving rise to PDAC. Although ADM formation is frequently observed in KrasG12D transgenic mouse models of PDAC, the exact mechanisms of how oncogenic KrasG12D regulates this process remain an enigma. Herein, we revealed a new downstream target of oncogenic Kras, cytokine CCL9, during ADM formation. Higher levels of CCL9 and its receptors, CCR1 and CCR3, were detected in ADM regions of the pancreas in p48cre:KrasG12D mice and human PDAC patients. Knockdown of CCL9 in KrasG12D-expressed pancreatic acini reduced KrasG12D-induced ADM in a 3D organoid culture system. Moreover, exogenously added recombinant CCL9 and overexpression of CCL9 in primary pancreatic acini induced pancreatic ADM. We also showed that, functioning as a downstream target of KrasG12D, CCL9 promoted pancreatic ADM through upregulation of the intracellular levels of reactive oxygen species (ROS) and metalloproteinases (MMPs), including MMP14, MMP3 and MMP2. Blockade of MMPs via its generic inhibitor GM6001 or knockdown of specific MMP such as MMP14 and MMP3 decreased CCL9-induced pancreatic ADM. In p48cre:KrasG12D transgenic mice, blockade of CCL9 through its specific neutralizing antibody attenuated pancreatic ADM structures and PanIN lesion formation. Furthermore, it also diminished infiltrating macrophages and expression of MMP14, MMP3 and MMP2 in the ADM areas. Altogether, our results provide novel mechanistic insight into how oncogenic Kras enhances pancreatic ADM through its new downstream target molecule, CCL9, to initiate PDAC.

Impacts of pancreatic exocrine insufficiency on gut microbiota.

Pancreatic exocrine insufficiency (PEI) can be induced by various kinds of diseases, including chronic pancreatitis, acute pancreatitis, and post-pancreatectomy. The main pathogenetic mechanism of PEI involves the decline of trypsin synthesis, disorder of pancreatic fluid flow, and imbalance of secretion feedback. Animal studies have shown that PEI could induce gut bacterial overgrowth and dysbiosis, with the abundance of Lactobacillus and Bifidobacterium increasing the most, which could be partially reversed by pancreatic enzyme replacement therapy. Clinical studies have also confirmed the association between PEI and the dysbiosis of gut microbiota. Pancreatic exocrine secretions and changes in duodenal pH as well as bile salt malabsorption brought about by PEI may affect and shape the abundance and composition of gut microbiota. In turn, the gut microbiota may impact the pancreatic exocrine acinus through potential bidirectional crosstalk. Going forward, more and higher-quality studies are needed that focus on the mechanism underlying the impact of PEI on the gut microbiota.

Морфофункциональная характеристика печени и поджелудочной железы при воздействии гепатопротектора Ремаксол на фоне острого алкогольного воздействия у крыс

Purpose of the study. To study the effect of hepatoprotective drug Remaxol on morphology of the liver and pancreas as well as on biochemical indices of blood serum in rats with alcohol damage. Material and methods. The study was carried out on sexually mature male white laboratory rats divided into three groups: 1st control group – intact animals (2 rats); 2nd – experimental animals (5 rats), on which acute pancreatitis on the background of alcohol poisoning was modeled by daily administration of 40% aqueous ethanol solution at a dose of 5 mg/kg weight for 7 days without treatment; 3rd – experimental group (5 rats) with alcohol exposure and with administration of Remaxol at a dose of 5 mg/kg weight daily for another 7 days. Morphological study of the liver, its macrostructure was carried out, diameters of hepatocytes and pancreatic acinuses in animals of experimental and control groups were measured, biochemical parameters were estimated. Results. Blood tests indicate acute alcohol poisoning in the experimental groups; short-term (7 days) alcohol damage has less effect on the size of hepatocytes than on the size of pancreatic acini; pancreatic acini were more reactive to the toxic effect of alcohol; against the background of insignificant morphometric differences, the morphological signs of cells and organs changed; in the liver and pancreas there were signs of inflammatory (swelling of cells in the liver and pancreas). Conclusion. Histological picture of the liver and pancreas of animals with acute alcohol damage against the background of Remaxol treatment showed a decrease in the toxic effect of 40% alcohol on hepatocytes and pancreatocytes, normalization of their morphological parameters.

Abstract 5325: Cytokine CCL9, new downstream target of oncogene Kras to modulate acinar-to-ductal metaplasia during pancreatic cancer initiation

Abstract Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of cancer with a current five-year survival rate at 12% in the US, and is dominated by oncogenic Kras mutations. Accumulating evidence showed that PDAC can be originated from acinar-to-ductal metaplasia (ADM). In this process, pancreatic acini harboring oncogenic Kras mutations are transdifferentiated to a duct-like phenotype that further progresses to become pancreatic intraepithelial neoplasia (PanIN) lesions, giving rise to PDAC. Although ADM formation is commonly observed in KrasG12D transgenic mouse models of PDAC, the exact mechanisms of how oncogenic KrasG12D modulates this process remain unclear. Here, we unveil a new downstream target of oncogenic Kras, cytokine CCL9 during ADM formation. Either exogenously treating primary pancreatic acini with recombinant CCL9 or ectopically expressing CCL9 in primary pancreatic acini resulted in ADM formation in a 3D organoid culture system. Furthermore, knockdown of CCL9 in KrasG12D-expressed acini reduced KrasG12D-induced ADM. Higher levels of reactive oxygen species (ROS) were detected in the KrasG12D-expressed pancreatic acini, and knockdown of CCL9 in these acini decreased ROS levels. Overexpression of CCL9 in primary pancreatic acini elevated cellular ROS of pancreatic acinar cells. Furthermore, depletion of ROS in 3D organoid culture of CCL9-expressed acini reduced CCL9-induced ADM formation. In transgenic mice of p48cre:KrasG12D, blockade of CCL9 through its specific neutralizing antibody attenuated ADM formation as well as PanIN structures. Altogether, our results indicated oncogenic KrasG12D initiates PDAC through a new downstream target molecule, CCL9, to enhance ROS levels of pancreatic acinar cells. Citation Format: Geou-Yarh (Stancy) Liou, Justin K. Messex, Crystal J. Byrd. Cytokine CCL9, new downstream target of oncogene Kras to modulate acinar-to-ductal metaplasia during pancreatic cancer initiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5325.

Morphofunctional characteristics of the liver and pancreas under the influence of the hepatoprotector “Remaxol” against the background of acute alcohol damage in rats

The goal. To study the effect of hepatoprotective drug “Remaxol” on morphology of the liver and pancreas as well as on blood serum indices in rats with alcohol damage. Materials and Methods. The study was conducted on mature male white laboratory rats divided into three groups: the first (control group) - intact animals, the second and third (experimental groups) - daily part of the rats received 40 % aqueous ethanol solution (96 % ethanol in a dose of 8ml/kg weight) for 7 days, then part of the rats from the experimental group were injected “Remaxol” in a dose 5 mg/kg weight daily for 7 days. Morphological study of the liver and its macrostructure was carried out; diameters of hepatocytes, sinusoid capillaries and pancreatic acini in animals of the control and experimental groups were measured; general and biochemical blood parameters were assessed. Results. Blood tests demonstrated acute alcohol poisoning in experimental groups (leukocytosis); short-term (7 days) alcohol damage had less effect on the size of hepatocytes than on the size of pancreatic acini; pancreatic acini were more reactive on toxic influence of alcohol; in the liver and pancreas there were signs of inflammatory reaction (cell swelling, lymphocytes infiltration). Conclusion. Histological picture of the liver and pancreas of the animals with acute alcohol poisoning on the background of “Remaxol” treatment showed a decrease in the toxic effect of 40 % alcohol on hepatocytes and pancreatocytes, normalization of their morphological parameters.

MARCH9, a potential target for the treatment of acute pancreatitis, inhibits NLRP3 inflammasome mediated pyroptosis

Purpose: To investigate the regulatory mechanism of membrane associated ring-CH-type finger 9 (MARCH9) in acute pancreatitis (AP).&#x0D; Methods: Fifteen AP patients admitted in Changzhou Second People's Hospital Nanjing, China and fifteen healthy individuals participated in this study. MARCH9 expression in serum samples taken from the subjects was assayed. To establish an AP cell model, rat pancreatic acinar (PA) cells were induced with ceruletide and then transfected with MARCH9 overexpression vector. The MARCH9 level and molecular structure, which are related to pyroptosis and inflammatory cytokines, were determined. Cell survival rate and caspase 1 activity was assessed.&#x0D; Results: MARCH9 was lowly expressed in AP patients’ serum and in ceruletide-induced PA cells. Overexpression of MARCH9 enhanced the survival rate of ceruletide-induced PA cells and reduced the levels of inflammatory cytokines and molecules associated with pyroptosis. MARCH9 overexpression led to a decrease in caspase 1 activity in ceruletide-induced PA cells. Additionally, the overexpression of MARCH9 had a negative regulatory effect on the levels of IL6, p-STAT3/STAT3 and p-JAK2/JAK2 in PA cells induced by ceruletide.&#x0D; Conclusion: Overexpression of MARCH9 suppresses NLRP3-induced pyroptosis in PA cells through the regulation of IL6/JAK/STAT3 pathway, thus offerimg insights for the potential management of AP.

Rab7 localized on zymogen granules is involved in maturation but not in autophagy or regulated exocytosis in pancreatic acinar cells

Rab7 is known to function in the autophagy and endocytosis pathways in eukaryocytes and is related to various diseases. We recently reported that Rab7 plays a protective role against acute pancreatitis. However, its physiological function in exocytic cells remains unclear. Therefore, we investigated the role of Rab7 in pancreas-specific Rab7 knockout mice (Rab7Δpan). Immunofluorescence microscopy revealed that Rab7 colocalized with amylase in pancreatic acinar cells of wild-type mice, but not in Rab7Δpan mice. Western blotting confirmed Rab7 localization in the zymogen granule (ZG) membranes of wild-type mice. Cholecystokinin (CCK)-stimulated amylase secretion examined using isolated pancreatic acini was similar in Rab7Δpan and wild-type mice. In contrast, electron microscopy revealed that the diameters of ZGs were shorter and the number of ZGs was larger in the pancreatic acinar cells of Rab7Δpan mice than in those of wild-type mice. However, the number of ZGs decreased in both Rab7Δpan and wild-type mice after 24 h of starvation. In addition, the amount of amylase in the pancreas was decreased in both Rab7Δpan and wild-type mice. These data indicate that Rab7 localized on ZGs plays a crucial role in the maturation of ZGs but not in their autophagy or regulated exocytosis in pancreatic acinar cells.

Hippocampal Microglia Activation Induced by Acute Pancreatic Injury in Rats.

Acute pancreatitis is an inflammation of the pancreatic glandular parenchyma that causes injury with or without the destruction of pancreatic acini. Clinical and experimental evidence suggest that certain systemic proinflammatory mediators may be responsible for initiating the fundamental mechanisms involved in microglial reactivity. Here, we investigated the possible repercussions of acute pancreatitis (AP) on the production of inflammatory mediators in the brain parenchyma focusing on microglial activation in the hippocampus. The acute pancreatic injury in rats was induced by a pancreas ligation surgical procedure (PLSP) on the splenic lobe, which corresponds to approximately 10% of total mass of the pancreas. Blood samples were collected via intracardiac puncture for the measurement of serum amylase. After euthanasia, frozen or paraffin-embedded brains and pancreas were analyzed using qRT-PCR or immunohistochemistry, respectively. Immunohistochemistry assays showed a large number of Iba1 and PU.1-positive cells in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus of the PLSP group. TNF-α mRNA expression was significantly higher in the brain from PLSP group. NLRP3 inflammasome expression was found to be significantly increased in the pancreas and brain of rats of the PLSP group. High levels of BNDF mRNA were found in the rat brain of PLSP group. In contrast, NGF mRNA levels were significantly higher in the control group versus PLSP group. Our findings suggest that AP has the potential to induce morphological changes in microglia consistent with an activated phenotype.

Exocrine pancreatic insufficiency in dogs and cats.

Exocrine pancreatic insufficiency (EPI) is a malabsorptive syndrome caused by insufficient secretion of digestive enzymes from pancreatic acini. The most common causes of EPI in dogs and cats are pancreatic acinar atrophy and chronic pancreatitis. EPI is diagnosed by measurement of species-specific immunoassays for serum trypsin-like immunoreactivity, the concentration of which directly reflects the mass of functioning pancreatic acinar tissue. EPI is treated by pancreatic enzyme replacement therapy, nutritional management (low-residue diets with moderate fat content), and supplementation of cobalamin. Some dogs and cats have persistent clinical signs despite these treatments. Growing evidence suggests that these clinical signs may be due to enteric microbiota dysbiosis or the presence of concurrent diseases such as chronic enteropathies. Management of these abnormalities may improve outcome in dogs and cats with EPI. The long-term prognosis for dogs and cats with EPI is generally good if high-quality medical therapy is provided. Future studies are needed to further understand the causes of persistent dysbiosis in animals with EPI following initiation of pancreatic enzyme replacement therapy and assess the efficacy of treatments to ameliorate these abnormalities.

Uncoupled respiration stability of isolated pancreatic acini as a novel functional test for cell vitality

Background. Assessment of cell viability is crucial in cell studies. Testing plasma membrane integrity is a traditional approach of evaluating cell viability. Mitochondrial functional capacity closely correlates with plasma membrane integrity and overall cell health. This study aimed to investigate whether any aspect of mitochondrial adaptive capacity in isolated pancreatic acini is associated with the quality of isolated pancreatic acini preparations, as determined by the dye exclusion method. Materials and Methods. Experiments were carried out on male Wistar rats weig­hing 250–300 g. A suspension of isolated pancreatic acini was obtained using collagenase. The rate of oxygen consumption of rat isolated pancreatic acini was measured with Clark oxygen electrode. Basal respiration of isolated pancreatic acini was recorded for approximately 2 min. Afterwards, the mitochondrial adaptive capacity was examined using FCCP in concentrations from 0.5 to 2 μM. Uncoupled respiratory stability was calculated as a ratio of respiration rate at high and low FCCP concentrations. Plasma membrane integrity was assessed with trypan blue staining. A total of 74 preparations of isolated pancreatic acini were used in this study. Results. In all experiments, 92–99 % of pancreatic acinar cells exhibited negative trypan blue staining, indicating intact plasma membranes. The basal and maximal uncoupled respiration rates were not affected by the fraction of trypan-negative cells. However, acini preparations with &lt;less than 95 % plasma membrane integrity had significantly lower uncoupled respiration rates when exposed to a high concentration of FCCP (2 µM), indicating reduced stability of uncoupled respiration. Conclusions. Results of the study suggest that the stability of uncoupled respiration can serve as a novel metabolic functional test to complement the existing methods for assessing cell vitality.

Structural and immunohistochemical characterization of pancreas of Molly fish (Poecilia sphenops), with a special reference to its immune role.

Recently, teleost species have been considered important model systems for investigating different research areas including immunologic one. The available literature provides poor data about the localization and the structure of pancreas in Molly fish. Moreover, little attention has been paid to the immunologic role of pancreatic tissue of teleost, particularly Molly fish; therefore, this study aimed to highlights the description of pancreatic tissue in Molly fish using light- and electron- microscopy, focusing on the role of pancreatic immune cells and pancreatic acinar cells in immune responses. Microscopic analysis revealed that the pancreas of Molly fish was composed of intrahepatic, disseminated and compact parts. Exocrine pancreatic tissue was diffusely extended within the hepatic tissue forming hepatopancreas. The disseminated pancreas appeared as several irregular nodules of pancreatic tissue localized within the mesenteric adipose tissue. The compact pancreas appeared as an oval shaped body embedded within the mesenteric adipose tissue between the spleen and the intestinal loops. Several telocytes and melanomacrophages were detected within the disseminated pancreatic nodules. Moreover, dendritic cells were found in a close association to the exocrine pancreatic acini. The pancreatic acinar cells showed strong immunoreactivity to APG5, TGF-β, IL-1β, NF-κB, Nrf2, and SOX9 in both hepatopancreas and disseminated pancreas of Molly fish. S100 protein revealed a strong expression in the exocrine pancreatic acinar cells of disseminated pancreas and also in the endocrine cells of the compact pancreas. In conclusion, findings of this study suggest the potential role of the pancreas of the Molly fish in cell proliferation and differentiation, proinflammatory cytokines stimulation, and regulation of both innate and adaptive immunity. RESEARCH HIGHLIGHTS: Telocytes and melanomacrophages were detected in the disseminated pancreatic nodules of the Molly fish. In Molly fish, dendritic cells were found in a close association to the exocrine pancreatic acini. Strong immunoreactivity of the pancreatic acinar cells of the Molly fish to APG5, TGF-β, IL-1β, NF-κB, Nrf2, SOX9, and S100.

Acalypha wilkesiana Exhibits Antihyperglycemic Potentials and Ameliorates Damages to Pancreas and Spleen of Diabetic Rat Model

Background: The present study investigated the antihyperglycemic and ameliorative effect of aqueous leaves extract of Acalypha wilkesiana on alloxan-induced diabetic male rats. The experimental rats were divided into six groups. Rats of the first group served as normal controls. Rats of the second group were negative control as they were induced with diabetes without treatment. The third group was treated with glibenclamide after induction of diabetes. The fourth, fifth and sixth groups were diabetic rats, treated with aqueous leaves extract of Acalypha wilkesiana at low dose (100mg/kg body weight), medium dose (200mg/kg body weight) and high dose (400mg/kg body weight) respectively. The blood glucose levels of the animals in each group were checked on day 5, 10 and 15 to examine the antihyperglycemic effect of the aqueous leaves extract of Acalypha wilkesiana. Also, on day 5, 10 and 15, the pancreas and spleen of experimental animals from each group were harvested for histological examination. Result: The result obtained showed that the graded doses of the extract significantly (p&lt;0.05) reduced the blood glucose levels of the diabetic animals in a dose-dependent manner. Also, the histological examination of the pancreas and spleen of the experimental animals treated with aqueous leaves extract of Acalypha wilkesiana showed normal pancreatic islet (PI) filled with islet cells (Granular appearance) and pancreatic acini (PA), while normal spleen with white pulp containing periarteriolar lymphatic sheath (PALS) and central arteriole (CA), splenic cord (SC) and sinusoids (SS) were seen in the same animals treated with the extract. The effect of the extract was similar in action to the standard drug glibenclamide. Conclusion: The aqueous leaves extract of Acalypha wilkesiana possesses antihyperglycemic potentials and ameliorates the pancreas and spleen of diabetic albino rats.

Driver Mutations of Pancreatic Cancer Affect Ca2+ Signaling and ATP Production.

Glandular pancreatic epithelia of the acinar or ductal phenotype may seem terminally differentiated, but they are characterized by remarkable cell plasticity. Stress-induced trans-differentiation of these cells has been implicated in the mechanisms of carcinogenesis. Current consensus links pancreatic ductal adenocarcinoma with onco-transformation of ductal epithelia, but under the presence of driver mutations in Kras and Trp53, also with trans-differentiation of pancreatic acini. However, we do not know when, in the course of cancer progression, physiological functions are lost by mutant acinar cells, nor can we assess their capacity for the production of pancreatic juice components. Here, we investigated whether two mutations-KrasG12D and Trp53R172H-present simultaneously in acinar cells of KPC mice (model of oncogenesis) influence cytosolic Ca2+ signals. Since Ca2+ signals control the cellular handling of digestive hydrolases, any changes that affect intracellular signaling events and cell bioenergetics might have an impact on the physiology of the pancreas. Our results showed that physiological doses of acetylcholine evoked less regular Ca2+ oscillations in KPC acinar cells compared to the control, whereas responses to supramaximal concentrations were markedly reduced. Menadione elicited Ca2+ signals of different frequencies in KPC cells compared to control cells. Finally, Ca2+ extrusion rates were significantly inhibited in KPC cells, likely due to the lower basal respiration and ATP production. Cumulatively, these findings suggest that driver mutations affect the signaling capacity of pancreatic acinar cells even before the changes in the epithelial cell morphology become apparent.

Cofilin activation in pancreatic acinar cells plays a pivotal convergent role for mediating CCK-stimulated enzyme secretion and growth.

Introduction: The actin regulatory protein, cofilin plays a key signaling role in many cells for numerous cellular responses including in proliferation, development, motility, migration, secretion and growth. In the pancreas it is important in islet insulin secretion, growth of pancreatic cancer cells and in pancreatitis. However, there are no studies on its role or activation in pancreatic acinar cells. Methods: To address this question, we studied the ability of CCK to activate cofilin in pancreatic acinar cells, AR42J cells and CCK1-R transfected Panc-1 cells, the signaling cascades involved and its effect on enzyme secretion and MAPK activation, a key mediator of pancreatic growth. Results: CCK (0.3 and 100nM), TPA, carbachol, Bombesin, secretin and VIP decreased phospho-cofilin (i.e., activate cofilin) and both phospho-kinetic and inhibitor studies of cofilin, LIM kinase (LIMK) and Slingshot Protein Phosphatase (SSH1) demonstrated these conventional activators of cofilin were not involved. Serine phosphatases inhibitors (calyculin A and okadaic acid), however inhibited CCK/TPA-cofilin activation. Studies of various CCK-activated signaling cascades showed activation of PKC/PKD, Src, PAK4, JNK, ROCK mediated cofilin activation, but not PI3K, p38, or MEK. Furthermore, using both siRNA and cofilin inhibitors, cofilin activation was shown to be essential for CCK-mediated enzyme secretion and MAPK activation. Conclusion: These results support the conclusion that cofilin activation plays a pivotal convergent role for various cell signaling cascades in CCK mediated growth/enzyme secretion in pancreatic acini.