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Congenital pseudomyotonia in cattle (PMT) is a rare skeletal muscle disorder, clinically characterized by stiffness and by delayed muscle relaxation after exercise. Muscle relaxation impairment is due to defective content of the Sarco(endo)plasmic Reticulum Ca2+ ATPase isoform 1 (SERCA1) protein, caused by missense mutations in the ATP2A1 gene. PMT represents the only mammalian model of human Brody myopathy. In the Romagnola breed, two missense variants occurring in the same allele were described, leading to Gly211Val and Gly286Val (G211V/G286V) substitutions. In this study, we analyzed the consequences of G211V and G286V mutations. Results support that the reduced amount of SERCA1 is a consequence of the G211V mutation, the G286V mutation almost being benign and the ubiquitin–proteasome system (UPS) being involved. After blocking the proteasome using a proteasome inhibitor, we found that the G211V mutant accumulates in cells at levels comparable to those of WT SERCA1. Our conclusion is that G211/286V mutations presumably originate in a folding-defective SERCA1 protein, recognized and diverted to degradation by UPS, although still catalytically functional, and that the main role is played by G211V mutation. Rescue of mutated SERCA1 to the sarcoplasmic reticulum membrane can re-establish resting cytosolic Ca2+ concentration and prevent the appearance of pathological signs, paving the way for a possible therapeutic approach against Brody disease. [ABSTRACT FROM AUTHOR]

Congenital pseudomyotonia in cattle (PMT) is a rare skeletal muscle disorder, clinically characterized by stiffness and by delayed muscle relaxation after exercise. Muscle relaxation impairment is due to defective content of the Sarco(endo)plasmic Reticulum Ca2+ ATPase isoform 1 (SERCA1) protein, caused by missense mutations in the ATP2A1 gene. PMT represents the only mammalian model of human Brody myopathy. In the Romagnola breed, two missense variants occurring in the same allele were described, leading to Gly211Val and Gly286Val (G211V/G286V) substitutions. In this study, we analyzed the consequences of G211V and G286V mutations. Results support that the reduced amount of SERCA1 is a consequence of the G211V mutation, the G286V mutation almost being benign and the ubiquitin–proteasome system (UPS) being involved. After blocking the proteasome using a proteasome inhibitor, we found that the G211V mutant accumulates in cells at levels comparable to those of WT SERCA1. Our conclusion is that G211/286V mutations presumably originate in a folding-defective SERCA1 protein, recognized and diverted to degradation by UPS, although still catalytically functional, and that the main role is played by G211V mutation. Rescue of mutated SERCA1 to the sarcoplasmic reticulum membrane can re-establish resting cytosolic Ca2+ concentration and prevent the appearance of pathological signs, paving the way for a possible therapeutic approach against Brody disease.

Background: Infectious diseases such as ventilator- associated pneumonia (VAP) are one of the serious problems in intensive care units (ICU) of hospitals. To date, there has been no appropriate clinical and diagnostic marker for early detection of this disease. In this study, expression of PIK3R3 and ATp2A1 genes in patients with VAP were assessed to be used as biomarkers to identify and confirm the disease. Methods: This study was conducted by using peripheral blood samples of 60 individuals, including 30 patients with VAP and 30 healthy volunteers. First, the peripheral blood samples were taken and then RNA was extracted and converted into cDNA. Finally, the assessment of genes was performed by Real-time PCR. Results: In peripheral blood samples, 46.6% and 30% were positive for PIK3R3 expression in patients and healthy groups, respectively. The ATp2A1 expression in patients and healthy controls were found 40% and 23.3%, respectively. Comparing the ΔCT obtained for the PIK3R3 and ATp2A1 genes showed statistically significant differences between the two groups of patients and healthy subjects (p=0.042, p=0.036). Conclusions: ATp2A1 and PIK3R3 may be used as biomarkers for early detection of VAP disease. However, further studies are required. [ABSTRACT FROM AUTHOR]

Abstract: Brody disease is an inherited myopathy associated with a defective function of sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 1 (SERCA1) protein. Mutations in the ATP2A1 gene have been reported only in some patients. Therefore it has been proposed to distinguish patients with ATP2A1 mutations, Brody disease (BD), from patients without mutations, Brody syndrome (BS). We performed a detailed study of SERCA1 protein expression in muscle of patients with BD and BS, and evaluated the alternative splicing of SERCA1 in primary cultures of normal human muscle and in infant muscle. SERCA1 reactivity was observed in type 2 muscle fibers of patients with and without ATP2A1 mutations and staining intensity was similar in patients and controls. Immunoblot analysis showed a significant reduction of SERCA1 band in muscle of BD patients. In addition we demonstrated that the wild type and mutated protein exhibits similar solubility properties and that RIPA buffer improves the recovery of the wild type and mutated SERCA1 protein. We found that SERCA1b, the SERCA1 neonatal form, is the main protein isoform expressed in cultured human muscle fibers and infant muscle. Finally, we identified two novel heterozygous mutations within exon 3 of the ATP2A1 gene from a previously described patient with BD. [Copyright &y& Elsevier]

Background: Infectious diseases such as ventilator- associated pneumonia (VAP) are one of the serious problems in intensive care units (ICU) of hospitals. To date, there has been no appropriate clinical and diagnostic marker for early detection of this disease. In this study, expression of PIK 3 R 3 and ATp 2 A 1 genes in patients with VAP were assessed to be used as biomarkers to identify and confirm the disease., Methods: This study was conducted by using peripheral blood samples of 60 individuals, including 30 patients with VAP and 30 healthy volunteers. First, the peripheral blood samples were taken and then RNA was extracted and converted into cDNA. Finally, the assessment of genes was performed by Real-time PCR., Results: In peripheral blood samples, 46.6% and 30% were positive for PIK 3 R 3 expression in patients and healthy groups, respectively. The ATp 2 A 1 expression in patients and healthy controls were found 40% and 23.3%, respectively. Comparing the ΔCT obtained for the PIK 3 R 3 and ATp 2 A 1 genes showed statistically significant differences between the two groups of patients and healthy subjects (p=0.042, p=0.036)., Conclusion: ATp 2 A 1 and PIK 3 R 3 may be used as biomarkers for early detection of VAP disease. However, further studies are required.