Calcium Channel Subunit α2δ-1 as a Potential Biomarker Reflecting Illness Severity and Neuroinflammation in Patients with Acute Ischemic Stroke.

BACKGROUND: Voltage-gated calcium channels (VGCCs) dysfunction is involved in the development of acute ischemic stroke (AIS). As a subunit of VGCC complexes, we detected the levels of α2δ-1 subunit in serum and cerebrospinal fluid (CSF) specimens from AIS patients. METHODS: The study included 105 patients with first-ever AIS, who were admitted within 48 hours after stroke onset. The serum and CSF levels of α2δ-1 were measured with ELISA and the severity of AIS patients was evaluated according to the National Institutes of Health Stroke Scale (NIHSS) score. The cerebral infarct volume was calculated through the Pullicino formula based on the cranial CT or MRI scan. C-reactive protein (CRP) and serum amyloid A (SAA) were measured using the latex-enhanced immunoturbidimetric assay. RESULTS: Compared to the control subjects, the serum α2δ-1 level was significantly increased in AIS patients with large infarct volume and in severe AIS cases with high NIHSS score, which correlated positively with the inflammatory markers CRP and SAA. Furthermore, the concentration of α2δ-1 in CSF was elevated with the infarct volume, which was higher in severe AIS patients. CONCLUSION: Our study suggests that the increased α2δ-1 levels in serum and CSF specimens may be used as a potential marker for reflecting VGCCs dysfunction, illness severity and neuroinflammation in AIS patients.

TRPV6 Is Associated with Prognosis of ST-Elevation Acute Myocardial Infarction.

OBJECTIVE: To investigate the relationship between Transient Receptor Potential Vanilloid 6 (TRPV6) and ST-elevation acute myocardial infarction (STEMI) patients. METHODS: This observational research included a total of 221 patients with STEMI admitted during January 2017~August 2019. Additionally, 50 cases of non-ST-elevation acute myocardial infarction (NSTEMI) patients and 50 healthy individuals were enrolled as the control. Serum levels of TRPV6 were detected by ELISA method. The relationship between TRPV6, clinical characteristics, laboratory indices of CK-MB, TnI, NT-pro-B-type natriuretic peptide (NT-pro-BNP), C-reactive protein (CRP), and the left ventricular ejection fraction (LVEF%) was analyzed by statistical methods. K-M curve was performed for survival time. RESULTS: Serum levels of TRPV6 were remarkably lower in STEMI and NSTEMI patients compared with the healthy control. Levels of NT-pro-BNP and CK-MB were significantly higher and serum levels of TRPV6 were dramatically lower in deceased STEMI patients in comparison with the surviving patients. The levels of TRPV6 were negatively correlated with CK-MB and NT-pro-BNP. Meanwhile, TRPV6 was negatively expressed in tissues of STEMI patients and positively expressed in normal tissues. Patients with lower TRPV6 levels had remarkably lower LVEF ratio, higher GRACE scores, higher CK-MB and NT-pro-BNP levels, as well as higher ratios of cardiovascular death, malignant arrhythmia, cumulative MACE, and shorter survival time than patients with higher TRPV6. CONCLUSION: The lower expression of TRPV6 was associated with poor clinical outcomes and prognosis of STEMI patients.

Predictors of Renal Function and Calcifications in Primary Hyperparathyroidism: A Nested Case-Control Study.

Context: Some patients with primary hyperparathyroidism (PHPT) develop renal calcifications. Investigation of urinary and nonurinary risk factors are essential. Objective: We aimed to study the prevalence and potential biochemical predictors of renal calcifications. Design: Nested case-control study. Setting: University hospital. Participants: We identified 792 patients with PHPT from 2005 to 2015. We used biochemical data to validate the diagnosis of PHPT. Main Outcome Measures: The prevalence of renal calcifications defined as nephrolithiasis or nephrocalcinosis assessed by a routine CT scan at the time of diagnosis. Results: A total of 792 patients with PHPT were identified among whom 617 patients (78%) had a CT scan preformed. We found a prevalence of renal calcifications of 23%, equally frequent between sexes. A total of 76 patients (12%) had nephrolithiasis and 75 patients (12%) had nephrocalcinosis where 7 patients (1%) had both nephrolithiasis and nephrocalcinosis. Compared with patients without renal calcifications, patients with renal calcifications had significantly higher levels of ionized calcium, parathyroid hormone, and 24-hour calcium excretion (Pall < 0.01). Patients with nephrocalcinosis had higher plasma levels of phosphate and a higher calcium-phosphate product compared with patients with nephrolithiasis (Pall < 0.05). Impaired renal function (estimated glomerular filtration rate <60 mL/min) was observed in 12% of patients. However, no differences in renal function were observed between those with and without renal calcifications. Conclusion: Renal calcifications are frequent in patients with PHPT and are associated with the severity of the disease. Impaired renal function is also common in PHPT, but renal function was not associated with renal calcifications.

Novel identification and characterisation of Transient receptor potential melastatin 3 ion channels on Natural Killer cells and B lymphocytes: effects on cell signalling in Chronic fatigue syndrome/Myalgic encephalomyelitis patients.

BACKGROUND: Transient receptor potential melastatin 3 (TRPM3) cation channels are ubiquitously expressed by multiple cells and have an important regulatory role in calcium-dependent cell signalling to help maintain cellular homeostasis. TRPM3 protein expression has yet to be determined on Natural Killer (NK) cells and B lymphocytes. Multiple single nucleotide polymorphisms have been reported in TRPM3 genes from isolated peripheral blood mononuclear cells, NK and B cells in Chronic fatigue syndrome/Myalgic encephalomyelitis (CFS/ME) patients and have been proposed to correlate with illness presentation. The object of the study was to assess TRPM3 surface expression on NK and B lymphocytes from healthy controls, followed by a comparative investigation examining TRPM3 surface expression, and cytoplasmic and mitochondrial calcium influx in CD19(+) B cells, CD56(bright) and CD56(dim) cell populations from CFS/ME patients. RESULTS: TRPM3 cell surface expression was identified for NK and B lymphocytes in healthy controls (CD56(bright) TRPM3 35.72 % ± 7.37; CD56(dim) 5.74 % ± 2.00; B lymphocytes 2.05 % ± 0.19, respectively). There was a significant reduction of TRPM3 surface expression on CD19(+) B cells (1.56 ± 0.191) and CD56(bright) NK cells (17.37 % ± 5.34) in CFS/ME compared with healthy controls. Anti-CD21 and anti-IgM conjugated biotin was cross-linked with streptavidin,and subsequently treatment with thapsigargin. This showed a significant reduction in cytoplasmic calcium ion concentration in CD19(+) B lymphocytes. CD56(bright) NK cells also had a significant decrease in cytoplasmic calcium in the presence of 2-APB and thapsigargin in CFS/ME patients. CONCLUSIONS: The results from this preliminary investigation identify, for the first time, TRPM3 surface expression on both NK and B lymphocytes in healthy controls. We also report for the first time, significant reduction in TRPM3 cell surface expression in NK and B lymphocytes, as well as decreased intracellular calcium within specific conditions in CFS/ME patients. This warrants further examination of these pathways to elucidate whether TRPM3 and impaired calcium mobilisation has a role in CFS/ME.

Correlation Between DNA Methylation of TRPA1 and Chronic Pain States in Human Whole Blood Cells.

OBJECTIVES: Neuro-immune interactions with functional changes in the peripheral blood cells including changes in the transient receptor potential ankyrin 1 (TRPA1) appear to play a pivotal role in the development of chronic pain in humans. The aim of this study was to examine the association between TRPA1 DNA methylation in whole blood cells and the pain states in chronic pain patients. METHODS: After collecting blood samples from 12 chronic pain patients, the authors measured DNA methylation levels in whole blood cells. Significant associations between the patient's demographic data and the chronic pain states were determined by a multiple linear regression analysis that used age, body mass index, pain duration, depression, anxiety, cognitive impairment, activities of daily living, neuropathic pain, and pain states as the dependent variables, and the TRPA1 DNA methylation levels as the independent variables. RESULTS: Multiple regression analysis revealed a significant correlation between increases of the methylation levels of the CpG island in the TRPA1 gene and increases in the number of neuropathic pain symptoms, which were evaluated using the Douleur Neuropathique 4 (DN4) questionnaire. Decreases in the TRPA1 mRNA expression were also significantly related to increases in the DN4 score. The presence of a burning sensation, which is one of pain symptoms in the DN4 questionnaire, was significantly correlated with the increase in DNA methylation level of TRPA1. CONCLUSIONS: TRPA1 DNA methylation levels in whole blood cells appear to be associated with pain symptoms in chronic pain patients.

Novel identification and characterisation of Transient receptor potential melastatin 3 ion channels on Natural Killer cells and B lymphocytes: effects on cell signalling in Chronic fatigue syndrome/Myalgic encephalomyelitis patients

BACKGROUND: Transient receptor potential melastatin 3 (TRPM3) cation channels are ubiquitously expressed by multiple cells and have an important regulatory role in calcium-dependent cell signalling to help maintain cellular homeostasis. TRPM3 protein expression has yet to be determined on Natural Killer (NK) cells and B lymphocytes. Multiple single nucleotide polymorphisms have been reported in TRPM3 genes from isolated peripheral blood mononuclear cells, NK and B cells in Chronic fatigue syndrome/Myalgic encephalomyelitis (CFS/ME) patients and have been proposed to correlate with illness presentation. The object of the study was to assess TRPM3 surface expression on NK and B lymphocytes from healthy controls, followed by a comparative investigation examining TRPM3 surface expression, and cytoplasmic and mitochondrial calcium influx in CD19+ B cells, CD56bnght and CD56dim cell populations from CFS/ME patients. RESULTS: TRPM3 cell surface expression was identified for NK and B lymphocytes in healthy controls (CD56bright TRPM3 35.72 % ± 7.37; CD56dim 5.74 % ± 2.00; B lymphocytes 2.05 % ± 0.19, respectively). There was a significant reduction of TRPM3 surface expression on CD19+ B cells (1.56 ± 0.191) and CD56bright NK cells (17.37 % ± 5.34) in CFS/ME compared with healthy controls. Anti-CD21 and anti-IgM conjugated biotin was cross-linked with streptavidin,and subsequently treatment with thapsigargin. This showed a significant reduction in cytoplasmic calcium ion concentration in CD19+ B lymphocytes. CD56bright NK cells also had a significant decrease in cytoplasmic calcium in the presence of 2-APB and thapsigargin in CFS/ME patients. CONCLUSIONS: The results from this preliminary investigation identify, for the first time, TRPM3 surface expression on both NK and B lymphocytes in healthy controls. We also report for the first time, significant reduction in TRPM3 cell surface expression in NK and B lymphocytes, as well as decreased intracellular calcium within specific conditions in CFS/ME patients. This warrants further examination of these pathways to elucidate whether TRPM3 and impaired calcium mobilisation has a role in CFS/ME.

TPC2 mediates new mechanisms of platelet dense granule membrane dynamics through regulation of Ca2+ release.

Platelet dense granules (PDGs) are acidic calcium stores essential for normal hemostasis. They develop from late endosomal compartments upon receiving PDG-specific proteins through vesicular trafficking, but their maturation process is not well understood. Here we show that two-pore channel 2 (TPC2) is a component of the PDG membrane that regulates PDG luminal pH and the pool of releasable Ca(2+). Using a genetically encoded Ca(2+) biosensor and a pore mutant TPC2, we establish the function of TPC2 in Ca(2+) release from PDGs and the formation of perigranular Ca(2+) nanodomains. For the first time, Ca(2+) spikes around PDGs--or any organelle of the endolysosome family--are visualized in real time and revealed to precisely mark organelle "kiss-and-run" events. Further, the presence of membranous tubules transiently connecting PDGs is revealed and shown to be dramatically enhanced by TPC2 in a mechanism that requires ion flux through TPC2. "Kiss-and-run" events and tubule connections mediate transfer of membrane proteins and luminal content between PDGs. The results show that PDGs use previously unknown mechanisms of membrane dynamics and content exchange that are regulated by TPC2.

Non-paraneoplastic voltage-gated calcium channels antibody-mediated cerebellar ataxia responsive to IVIG treatment.

Non-paraneoplastic cerebellar ataxia associated with voltage-gated calcium channel (VGCC) antibodies is a rare entity with only few cases reported in literature. We describe a 60 year-old man with subacute cerebellar ataxia and subclinical Lambert-Eaton myasthenic syndrome (LEMS) in whom VGCC antibodies were detected at high titer in serum and cerebrospinal fluid. Screening for underlying malignancies was negative. Intravenous immunoglobulin treatment led to the improvement of clinical picture and reduction of serum antibody titer over a 13-month follow-up period. We emphasize that VGCC antibodies should be included in the diagnostic work-up of patients with subacute cerebellar ataxia and that treatment with IVIG can improve the clinical picture and prevent disability.

[The functional characteristics oF TRPV5 and TRPV6 channels in normal and transformed human blood lymphocytes].

Calcium signaling and Ca(2+)-conducting channels are involved in the development of immune response, cell proliferation, growth and differentiation of lymphocytes. In this paper the calcium channels TRPV5 and TRPV6 (transient receptor potential vanilloid channels) were studied in the plasma membrane of T cell line Jurkat and normal human blood lymphocytes. The channels were activated by removing Ca2+ and Mg2+ from surrounding solution, characterized by inward rectification, and were inactivated by the effective blocker of TRPV5 and TRPV6, ruthenium red. Channel activity was significantly higher in Jurkat cells, than in normal human lymphocytes. Quantitative PCR analysis revealed higher levels of mRNA genes encoding channels TRPV5 and TRPV6 in the proliferation cells compared with resting lymphocytes. In general these data showed that TRPV5/TRPV6 in human lymphocytes are functionally active, and their activity is associated with proliferative status of blood cells.