alpha-chymotrypsin and Fibrosis

The aim was to review evidence about diabetes secondary to hereditary pancreatitis, seeking novel diagnostic and treatment features.. Hereditary pancreatitis (HP) is an autosomal dominant condition, characterized by recurrent episodes of acute pancreatitis, progression to fibrosis, and chronic pancreatitis. Clinical presentation includes diabetes of the exocrine pancreas (DEP). HP prevalence ranges from 0.3 to 0.57 per 100,000 people, with up to 80% of these develop DEP. This condition often requires specific interventions: with regard to metabolic control, metformin is the first choice for those with mild DEP, and for those in advanced disease, insulin is considered the first-line therapy. Insulin analogues and insulin pump therapy are preferred due to the brittle glycemic pattern and risk of hypoglycemia. In case of exocrine insufficiency, pancreatic enzyme replacement therapy is recommended. Pancreatic polypeptide administration is a promising novel treatment feature. DEP due to HP appears to be a misdiagnosed condition. The requirement of specific management demonstrates the importance of this matter; therefore, appropriate recognition and classification are important.

Topics: Acute Disease; Carcinoma, Pancreatic Ductal; Chymotrypsin; Diabetes Complications; Diabetes Mellitus; Exocrine Pancreatic Insufficiency; Fibrosis; Humans; Pancreas, Exocrine; Pancreatic Neoplasms; Pancreatitis, Chronic; Recurrence; Risk Factors; Trypsin; Trypsin Inhibitor, Kazal Pancreatic

Hypertensive cardiac remodeling is a major cause of heart failure. The immunoproteasome is an inducible form of the proteasome and its catalytic subunit β5i (also named LMP7) is involved in angiotensin II-induced atrial fibrillation; however, its role in deoxycorticosterone-acetate (DOCA)-salt-induced cardiac remodeling remains unclear. C57BL/6 J wild-type (WT) and β5i knockout (β5i KO) mice were subjected to uninephrectomy (sham) and DOCA-salt treatment for three weeks. Cardiac function, fibrosis, and inflammation were evaluated by echocardiography and histological analysis. Protein and gene expression levels were analyzed by quantitative real-time PCR and immunoblotting. Our results showed that after 21 days of DOCA-salt treatment, β5i expression and chymotrypsin-like activity were the most significantly increased factors in the heart compared with the sham control. Moreover, DOCA-salt-induced elevation of blood pressure, adverse cardiac function, chamber and myocyte hypertrophy, interstitial fibrosis, oxidative stress, and inflammation were markedly attenuated in β5i KO mice. These findings were verified in β5i inhibitor PR-957-treated mice. Moreover, blocking of PTEN (the gene of phosphate and tensin homolog deleted on chromosome ten) markedly attenuated the inhibitory effect of β5i knockout on DOCA-salt-induced cardiac remodeling. Mechanistically, DOCA-salt stress upregulated the expression of β5i, which promoted the degradation of PTEN and the activation of downstream signals (AKT/mTOR, TGF-β1/Smad2/3, NOX, and NF-κB), which ultimately led to cardiac hypertrophic remodeling. This study provides new evidence of the critical role of β5i in DOCA-salt-induced cardiac remodeling through the regulation of PTEN stability, and indicates that the inhibition of β5i may be a promising therapeutic target for the treatment of hypertensive heart diseases.

Topics: Animals; Cardiomegaly; Chymotrypsin; Desoxycorticosterone Acetate; Fibrosis; Hypertension; Inflammation; Male; Mice, Inbred C57BL; Mice, Knockout; Oxidative Stress; Proteasome Endopeptidase Complex; Protein Subunits; PTEN Phosphohydrolase; Signal Transduction; Up-Regulation; Ventricular Remodeling

To determine the role of proteasome proteolysis in the pathogenesis of hypertension, we have studied the proteolytic activity of the proteasome in the aorta and heart tissues of rats with spontaneous hypertension (line SHR), and used quercetin, the drug that can inhibit the activity of this multicatalytic complex. In the aorta of SHR, the activities of the proteasome were not significantly different from that observed in Wistar rats. At the same time, in the heart tissues the trypsin-like (at 40%, P > 0.05), and chymotrypsin-like (by 1.7 times, P < 0.03) activities were significantly less in SHR. Significant morphological changes (fibrosis of the left ventricle was 4.7%, aorta intima width was increased and heart weight index was higher by 21.6% (3.7 +/- 0.6 mg/g) compared with Wistar rats (2.9 +/- 0,4 mg/g, P < 0.004) were observed in these animals functional disorders (reduced stroke volume by 3 times (P < 0.0001), ejection fraction by 2.5 times (P < 0.0001), increased end diastolic pressure by 6.5 times (P < 0.005), end systolic pressure by 15% (P < 0.004)) were revealed. Pharmacological drug "Qvercetin" effectively inhibited trypsin-like and chymotrypsin-like proteasome activities in the aorta (2.7-fold (P < 0.005) and 2-fold (P < 0.003), correspondingly) and trypsin-like, and peptidyl-glutamyl peptide-hydrolyzing-like activities (2.4-fold, P > 0.05 and 9.3-fold, P < 0.02, correspondingly) activities in the heart, leading to a significant improvement of morphological and functional parameters of the heart. Whereas the drug "Qvercetin" that is widely used in clinical practice (especially in therapy of acute myocardial infarction) it could be recommended for the use in prevention of cardiac remodeling with high level of blood pressure.

Topics: Animals; Antioxidants; Aorta; Blood Pressure; Chymotrypsin; Fibrosis; Heart Ventricles; Hypertension; Male; Proteasome Endopeptidase Complex; Quercetin; Rats; Rats, Inbred SHR; Rats, Wistar; Stroke Volume; Trypsin

Conformational diseases are caused by a structural rearrangement within a protein that results in aberrant intermolecular linkage and tissue deposition. This is typified by the polymers that form with the Z deficiency variant of alpha 1-antitrypsin (Glu-342 --> Lys). These polymers are retained within hepatocytes to form inclusions that are associated with hepatitis, cirrhosis, and hepatocellular carcinoma. We have assessed a surface hydrophobic cavity in alpha1-antitrypsin as a potential target for rational drug design in order to prevent polymer formation and the associated liver disease. The introduction of either Thr-114 --> Phe or Gly-117 --> Phe on strand 2 of beta-sheet A within this cavity significantly raised the melting temperature and retarded polymer formation. Conversely, Leu-100 --> Phe on helix D accelerated polymer formation, but this effect was abrogated by the addition of Thr-114 --> Phe. None of these mutations affected the inhibitory activity of alpha 1-antitrypsin. The importance of these observations was underscored by the finding that the Thr-114 --> Phe mutation reduced polymer formation and increased the secretion of Z alpha 1-antitrypsin from a Xenopus oocyte expression system. Moreover cysteine mutants within the hydrophobic pocket were able to bind a range of fluorophores illustrating the accessibility of the cavity to external agents. These results demonstrate the importance of this cavity as a site for drug design to ameliorate polymerization and prevent the associated conformational disease.

Topics: alpha 1-Antitrypsin; Animals; Binding Sites; Carcinoma, Hepatocellular; Chymotrypsin; Crystallography, X-Ray; Cysteine; Fibrosis; Glycine; Hepatitis; Hepatocytes; Hydrogen-Ion Concentration; Models, Molecular; Mutation; Oocytes; Phenylalanine; Polymers; Potassium Chloride; Protein Binding; Protein Conformation; Protein Structure, Secondary; Protein Structure, Tertiary; Recombinant Proteins; Temperature; Threonine; Time Factors; Xenopus