scholarly journals Activation and activity of glycosylated KLKs 3, 4 and 11

2018 ◽  
Vol 399 (9) ◽  
pp. 1009-1022 ◽  
Author(s):  
Shihui Guo ◽  
Peter Briza ◽  
Viktor Magdolen ◽  
Hans Brandstetter ◽  
Peter Goettig
Keyword(s):  
Physiological Function ◽  
Periodic Acid ◽  
Hek293 Cells ◽  
Secretory Expression ◽  
Detailed Characterization ◽  
Periodic Acid Schiff ◽  
Clinical Biomarkers ◽  
Schiff Reaction

Abstract Human kallikrein-related peptidases 3, 4, 11, and KLK2, the activator of KLK3/PSA, belong to the prostatic group of the KLKs, whose major physiological function is semen liquefaction during the fertilization process. Notably, these KLKs are upregulated in prostate cancer and are used as clinical biomarkers or have been proposed as therapeutic targets. However, this potential awaits a detailed characterization of these proteases. In order to study glycosylated prostatic KLKs resembling the natural proteases, we used Leishmania (LEXSY) and HEK293 cells for secretory expression. Both systems allowed the subsequent purification of soluble pro-KLK zymogens with correct propeptides and of the mature forms. Periodic acid-Schiff reaction, enzymatic deglycosylation assays, and mass spectrometry confirmed the glycosylation of these KLKs. Activation of glycosylated pro-KLKs 4 and 11 turned out to be most efficient by glycosylated KLK2 and KLK4, respectively. By comparing the glycosylated prostatic KLKs with their non-glycosylated counterparts from Escherichia coli, it was observed that the N-glycans stabilize the KLK proteases and change their activation profiles and their enzymatic activity to some extent. The functional role of glycosylation in prostate-specific KLKs could pave the way to a deeper understanding of their biology and to medical applications.

Acid-Sensing Ion Channels

2020 ◽  
Author(s):  
Stefan Gründer
Keyword(s):  
Nervous System ◽  
Ion Channels ◽  
Excitatory Synapses ◽  
Detailed Characterization ◽  
High Affinity ◽  
Acid Sensing Ion Channels ◽  
Long Time ◽  
Pathological Pain

Acid-sensing ion channels (ASICs) are proton-gated Na+ channels. Being almost ubiquitously present in neurons of the vertebrate nervous system, their precise function remained obscure for a long time. Various animal toxins that bind to ASICs with high affinity and specificity have been tremendously helpful in uncovering the role of ASICs. We now know that they contribute to synaptic transmission at excitatory synapses as well as to sensing metabolic acidosis and nociception. Moreover, detailed characterization of mouse models uncovered an unanticipated role of ASICs in disorders of the nervous system like stroke, multiple sclerosis, and pathological pain. This review provides an overview on the expression, structure, and pharmacology of ASICs plus a summary of what is known and what is still unknown about their physiological functions and their roles in diseases.

Histologic and Histochemical Characterization of Seminal Vesicle Intraluminal Secretions

2001 ◽  
Vol 125 (1) ◽  
pp. 141-145
Author(s):  
Rajal B. Shah ◽  
Min W. Lee ◽  
Alvaro A. Giraldo ◽  
Mahul B. Amin
Keyword(s):  
Seminal Vesicle ◽  
Alcian Blue ◽  
Prostate Carcinoma ◽  
Periodic Acid ◽  
Prostate Gland ◽  
Seminal Vesicles ◽  
Periodic Acid Schiff ◽  
Associated Malignancy ◽  
Distinguishing Features

Abstract Context.—We have observed intraluminal crystalloid morphology in seminal vesicles that is superficially similar to that seen in prostate neoplasia, but found little information on such morphology in the literature. Design.—Two hundred fifty-three prostate specimens (163 needle biopsies, 75 radical prostatectomies with prostate carcinoma, 11 prostates from autopsy, and 4 cystoprostatectomies without prostate carcinoma) were examined for seminal vesicle secretions, which were categorized as (a) dense platelike inspissated, (b) fluidlike, (c) crystalloid morphology, and (d) absent. Histochemical stains (periodic acid–Schiff with and without diastase, Alcian blue at pH 2.5, and mucicarmine) were performed to characterize the nature of secretions. Results.—Proteinaceous secretions were identified in 82% of seminal vesicles examined. Of these, 61% had predominantly dense, platelike, inspissated secretions, 15% had predominantly fluidlike secretions, and 24% had predominantly crystalloid morphology. Although in some cases the crystalloid morphology resembled that of prostatic intraluminal crystalloids, the seminal vesicle crystalloids differed in that they were invariably multiple, had curved edges, and had varied forms (elliptical, cylindrical, rodlike, and rectangular). Seventy-one percent of seminal vesicle crystalloids were associated with dense, platelike, inspissated secretions and appeared to be created by fracturing within platelike secretions. There was no relationship between seminal vesicle crystalloid morphology and associated malignancy in the prostate gland, as it was seen in 24% of cases with prostate carcinoma and 25% of cases without prostate carcinoma (P = 1.0000). Fluidlike secretions were positive for Alcian blue (pH 2.5) and mucicarmine, whereas dense platelike secretions and crystalloid morphology were negative for Alcian blue (pH 2.5) and mucicarmine. Conclusions.—Seminal vesicle secretions are fairly common and, when fluidlike, are composed of acid mucopolysaccharides. Inspissation of secretions appears to be associated with loss of acidity, presumably resulting in dense platelike secretions and crystallization. Awareness of both the crystalloid morphology in seminal vesicle tissue and the distinguishing features from prostatic crystalloids may be important while interpreting prostate needle biopsies in which seminal vesicle epithelium may be confused for prostate carcinoma because of a small acinar morphology with accompanying cytologic atypia and crystalloid morphology.

scholarly journals Effect of activity on performance and morphology in ischaemic rat slow muscles

1990 ◽  
Vol 152 (1) ◽  
pp. 265-279
Author(s):  
A. Corsi ◽  
A. L. Granata ◽  
O. Hudlicka
Keyword(s):  
Blood Supply ◽  
Periodic Acid ◽  
Capillary Density ◽  
Muscle Performance ◽  
Similar Proportion ◽  
Periodic Acid Schiff ◽  
Rat Soleus Muscle ◽  
Improved Performance ◽  
Isometric Twitch ◽  
Schiff Reaction

Muscle performance and structure was studied in rat soleus muscle with limited blood supply in combination with chronic muscle stimulation. Blood supply to the lower leg was restricted by ligation of the common iliac artery, electrodes were implanted in the vicinity of the sciatic nerve and ankle flexors were denervated. Three days later, soleus and gastrocnemius muscles were stimulated at 4 Hz four times a day for a period of 20 min with 2 h intervals between stimulations; this procedure was continued for 4 days. Muscle performance, histochemistry and ultrastructure were studied on the eighth day after operation in these muscles and in ischaemic unstimulated muscles with denervated ankle flexors. Both were compared with control animals. Muscles with limited blood supply developed less isometric twitch tension than control muscles (peak twitch tension in ischaemic muscle was 60.3 +/− 4.8 g g-1 muscle, mean +/− S.E.M., compared to 79.7 +/− 6.9 g g-1 in control muscle; tensions after 5 min contraction were 54.5 +/− 5.5 g g-1 in ischaemic muscle compared to 70.6 +/− 6 g g-1 in controls). Stimulated muscles with limited blood supply had higher peak (85 +/− 16.6 g g-1) and final (87 +/− 12 g g-1) tensions, and also fatigued less than muscles with limited blood supply but no stimulation. Histochemical estimation of capillary density (by staining for alkaline phosphatase) and slow (SO) and fast (FOG) fibres (by myosin ATPase staining) revealed similar capillary to fibre ratios (2.5) and a similar proportion of FOG fibres (around 18%) in all muscles. The proportion of glycogen-depleted fibres (estimated from the periodic acid Schiff reaction, PAS) in muscles removed from animals 10 min after a 5 min period of isometric twitches was significantly lower in ischaemic muscles (45.1 +/− 1.9%) than in control (80.5 +/− 1.5%) or chronically stimulated ischaemic muscles (67.3 +/− 4.0%). Electron microscopy showed disorganised myofibrils with Z-line streaming in 7.48 +/− 3.04% of fibres in muscles with limited blood supply. Swollen and degenerated mitochondria, dilated sarcoplasmic reticulum and areas of disrupted sarcolemma were also observed. Stimulated ligated muscles showed a significantly lower proportion of fibres with disorganised filaments (0.65 +/− 0.32%) and other signs of damage were much less frequent. The reduced damage and improved performance of chronically stimulated slow muscle may be the result of improved microcirculation, preventing accumulation of lactate.

scholarly journals Heme oxygenase-2 (HO-2) binds and buffers labile heme, which is largely oxidized, in human embryonic kidney cells

2021 ◽  
Author(s):  
David A Hanna ◽  
Courtney M Moore ◽  
Liu Liu ◽  
Xiaojing Yuan ◽  
Angela S Fleischhacker ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Physiological Function ◽  
Hek293 Cells ◽  
Kidney Cells ◽  
Human Embryonic Kidney ◽  
Human Embryonic Kidney Cells ◽  
Heme Oxygenases ◽  
Heme Trafficking ◽  
Ferrous Heme

Heme oxygenases (HO) detoxify heme by oxidatively degrading it into carbon monoxide, iron, and biliverdin, which is reduced to bilirubin and excreted. Humans express two isoforms: inducible HO-1, which is up-regulated in response to various stressors, including excess heme, and constitutive HO-2. While much is known about the regulation and physiological function of HO-1, comparatively little is known about the role of HO-2 in regulating heme homeostasis. The biochemical necessity for expressing constitutive HO-2 is largely dependent on whether heme is sufficiently abundant and accessible as a substrate under conditions in which HO-1 is not induced. By measuring labile heme, total heme, and bilirubin in human embryonic kidney HEK293 cells with silenced or over-expressed HO-2, and various HO-2 mutant alleles, we found that endogenous heme is too limiting to support HO-2 catalyzed heme degradation. Rather, we discovered that a novel role for HO-2 is to bind and buffer labile heme. Taken together, in the absence of excess heme, we propose that HO-2 regulates heme homeostasis by acting as a heme buffering factor in control of heme bioavailability. When heme is in excess, HO-1 is induced and both HO-2 and HO-1 can provide protection from heme toxicity by enzymatically degrading it. Our results explain why catalytically inactive mutants of HO-2 are cytoprotective against oxidative stress. Moreover, the change in bioavailable heme due to HO-2 overexpression, which selectively binds ferric over ferrous heme, is consistent with the labile heme pool being oxidized, thereby providing new insights into heme trafficking and signaling.

scholarly journals USG and CT scan evaluation of patients of acute and chronic pancreatitis- a cross-sectional, comparative study

2017 ◽  
Vol 5 (8) ◽  
pp. 3713 ◽  
Author(s):  
Aastha Bhatt ◽  
Awdhut Tiparse ◽  
Arpita Patel ◽  
Birwa Gandhi
Keyword(s):  
Ct Scan ◽  
Structural Changes ◽  
Radiation Hazard ◽  
Government Medical College ◽  
Detailed Characterization ◽  
Cross Sectional ◽  
Medical College ◽  
Adjacent Structures

Background: Pancreatitis is a condition of inflammation of pancreas with high rate of morbidity and mortality. USG provides the initial radiological assessment of the organ, clue of the extent of involvement and an opportunity to evaluate other abdominal organs. CT scan provides a cross-sectional anatomy of the organ, its internal structure, focal or diffuse involvement and involvement of adjacent structures. This study is done to evaluate the role of USG and CT scan in patients of pancreatitis admitted to Sir Takhtsinhji hospital, government medical college, Bhavnagar, Gujarat, India. Aim was to understand the role of CT and USG in determination of diagnosis of pancreatitis and to highlight and evaluate the cases in which USG failed to diagnose the cases which were helped through by CT.Methods: This study was done in department of radio diagnosis at Sir Takhtsinhji hospital, government medical college, Bhavnagar, Gujarat, India, over a period of one year from June 2015 to June 2016. Each patient was studied taking into consideration relevant clinical and laboratory factors. USG of patients was done using My Lab 40 or My Lab 20 plus machine. CT scan was done using GE 16 Slice CT scan machine.Results: Ultrasound by non-invasiveness, lack of radiation hazard and by ability to demonstrate structural changes in organ is first investigation of choice in pancreatitis. However, USG fails imaging in conditions with excess of bowel gas or fatty patient. It lacks in detailed characterization of the inflammatory process and does not delineate extent of necrosis of the gland. CT is superior to ultrasound for precise detection of size, parenchyma, MPD, calcification, pseudocyst, ascites, pleural effusion, necrosis and peri pancreatic region and hence helps to determine exact extent of inflammation of the organ, multi-system involvement and prognosis.Conclusions: Ultrasound by non-invasiveness, easy availability, cost parameters, lack of radiation hazard and by ability to demonstrate structural changes in organ is first investigation of choice in pancreatitis. However, ultrasonography lacks in detailed characterization of the extent of involvement of the organ and adjacent structures. CT is superior to ultrasound for precise detection and extension of the pancreatitis and it has better sensitivity and specificity than ultrasonography. 

scholarly journals THE HISTOCHEMICAL INTERPRETATION OF THE COMPLEX RESULTS OF METHYLATION UPON GASTROINTESTINAL TRACT MUCINS, WITH SPECIAL REFERENCE TO THE PERIODIC ACID-SCHIFF REACTIVITY

1974 ◽  
Vol 22 (10) ◽  
pp. 986-991 ◽  
Author(s):  
P. E. REID ◽  
C. F. A. CULLING ◽  
W. L. DUNN
Keyword(s):  
Sialic Acid ◽  
Gastrointestinal Tract ◽  
Special Reference ◽  
Periodic Acid ◽  
Separate Study ◽  
Sulfate Ester ◽  
Periodic Acid Schiff ◽  
Smith Degradation ◽  
Vicinal Diol ◽  
Schiff Reaction

The histochemical use of methylation has complex results; particularly in respect of the periodic acid-Schiff reaction, these are analyzed and discussed. Methods are described which allow the separate study of the following effects: (a) the removal of the KOH/periodic acid-Schiff effect; (b) removal of sialic acid from a potential vicinal diol; and (c) the removal of O-sulfate ester from a potential vicinal diol. The use of the Smith degradation technique, in addition to the above, also allows inferences to be drawn in respect of the structure of the mucins (glycoproteins) being investigated.

scholarly journals Acute lymphoblastic leukemia with unusual cytoplasmic granulation: a morphologic, cytochemical, and ultrastructural study

Blood ◽  
1986 ◽  
Vol 68 (2) ◽  
pp. 406-411 ◽  
Author(s):  
J Fradera ◽  
E Velez-Garcia ◽  
JG White
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Periodic Acid ◽  
Periodic Acid Schiff ◽  
Acute Leukemias ◽  
Ultrastructural Studies ◽  
Sudan Black B ◽  
Blast Cells ◽  
Chediak Higashi Syndrome ◽  
Schiff Reaction

Abstract The classification of the acute leukemias depends mainly on the morphologic and cytochemical evaluation of the blast forms. One of the main accepted morphologic criteria in the differentiation between acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) is the absence of granules in the blast cells of ALL. We evaluated a patient with ALL in whom granules were present in the cytoplasm of 35% of the blast cells, as seen in AML. Cytochemical evaluation was performed, including periodic acid-Schiff reaction, Sudan black B, alpha-naphthyl acetate, alpha-naphthyl butyrate, naphthol AS-D chloroacetate, and acid phosphatase stains. The results of these studies confirmed the morphologic impression and diagnosis of ALL. Ultrastructural evaluation revealed that the granules consisted of many tiny vesicles closely packed together in a proteinaceous matrix, resembling to some extent the inclusions described in lymphocytes in the Chediak-Higashi syndrome, but clearly different. The morphologic, cytochemical, and ultrastructural studies of this unique case are presented in detail. To our knowledge, this is the first time that such granules have been described in blast cells of ALL.

The periodic acid-Schiff reaction in the cornea of the developing chick

1960 ◽  
Vol 121 (5) ◽  
pp. 351-368 ◽  
Author(s):  
Ronan O'Rahilly ◽  
David B. Meyer
Keyword(s):  
Periodic Acid ◽  
Periodic Acid Schiff ◽  
Schiff Reaction

Clarithromycin inhibits overproduction of muc5ac core protein in murine model of diffuse panbronchiolitis

2003 ◽  
Vol 285 (4) ◽  
pp. L847-L853 ◽  
Author(s):  
Yukihiro Kaneko ◽  
Katsunori Yanagihara ◽  
Masafumi Seki ◽  
Misuzu Kuroki ◽  
Yoshitsugu Miyazaki ◽  
...  
Keyword(s):  
Core Protein ◽  
Periodic Acid ◽  
Protein A ◽  
Mitogen Activated Protein Kinase ◽  
Periodic Acid Schiff ◽  
Western Blots ◽  
Diffuse Panbronchiolitis ◽  
Mucin Production ◽  
Long Term Treatment

Long-term treatment of macrolide antibiotics is considered an effective treatment for diffuse panbronchiolitis (DPB). Although hypersecretion is a common feature of this disease, and it is known that macrolides inhibit mucin production, the mechanism of the effect on mucin production is unclear. The aim of our study was to determine the production of muc5ac core protein, a major core protein of mucin in airway secretion, and the effect of clarithromycin treatment on such production in a mouse model mimicking DPB. Alcian blue-periodic acid-Schiff-positive cells were detected in the lungs of Pseudomonas aeruginosa-infected mice. Western blots of these mice showed muc5ac glycoprotein at day 1 and increased progressively from day 4 to day 14 after inoculation of bacteria. Clarithromycin (10 mg · kg-1· day-1for 7 days) significantly reduced the muc5ac expression at both the mRNA and protein levels. To investigate the role of molecules upstream in muc5ac regulation, we examined the role of mitogen-activated protein kinase. Extracellular signal-regulated kinase 1/2 phosphorylation increased in the infected lung and decreased after treatment. Our results suggest that overproduction of muc5ac plays an important role in the pathogenesis of DPB and that clinical improvement following macrolide therapy seems to involve, at least in part, its inhibition of mucin overproduction, through modulation of intracellular signal transduction.

Sign in / Sign up

Export Citation Format

Share Document