Pituispheres Contain Genetic Variants Characteristic to Pituitary Adenoma Tumor Tissue

2020

The most common type of pituitary neoplasms is benign pituitary adenoma (PA). Clinically significant PAs affect around 0.1% of the population. Currently, there is no established human PA cell culture available and when PA tumor cells are cultured they form two distinct types depending on culturing conditions either free-floating aggregates also known as pituispheres or cells adhering to the surface of cell plates and displaying mesenchymal stem-like properties. The aim of this study was to trace the origin of sphere-forming and adherent pituitary cell cultures and characterize the potential use of these surgery derived cell lines as PA model. We carried out a paired-end exome sequencing of …

Medication for Acromegaly Reduces Expression of MUC16, MACC1 and GRHL2 in Pituitary Neuroendocrine Tumour Tissue

2021

Acromegaly is a disease mainly caused by pituitary neuroendocrine tumor (PitNET) overproducing growth hormone. First-line medication for this condition is the use of somatostatin analogs (SSAs), that decrease tumor mass and induce antiproliferative effects on PitNET cells. Dopamine agonists (DAs) can also be used if SSA treatment is not effective. This study aimed to determine differences in transcriptome signatures induced by SSA/DA therapy in PitNET tissue. We selected tumor tissue from twelve patients with somatotropinomas, with half of the patients receiving SSA/DA treatment before surgery and the other half treatment naive. Transcriptome sequencing was then carried out to identify diff…

Association between symptoms of depression, diabetes complications and vascular risk factors in four European cohorts of individuals with type 1 diab…

2020

Aims: To investigate the association between depressive symptomatology and health markers in type 1 diabetes. Methods: Four countries from the InterDiane Consortium had adopted the Finnish Diabetic Nephropathy Study protocol, including the Beck Depression Inventory (BDI). Associations between depression symptomatology, diabetes complications (diabetic nephropathy, proliferative retinopathy, major adverse cardiovascular events [MACE]) and vascular risk factors (metabolic syndrome, body mass index, glycaemic control) were investigated. Results: In a sample of 1046 participants (Croatia n = 99; Finland n = 314; Latvia n = 315; Lithuania n = 318), 13.4% displayed symptoms of depression (BDI sco…

Polymorphisms in FTO and near TMEM18 associate with type 2 diabetes and predispose to younger age at diagnosis of diabetes

2013

Variations in the FTO gene and near the TMEM18 gene are risk factors for common form of obesity, but have also been linked with type 2 diabetes (T2D). Our aim was to investigate the contribution of these variants to risk of T2D in a population in Latvia. Four single nucleotide polymorphisms (SNP) in the first and fourth intronic regions of FTO and one close to TMEM18 were genotyped in 987 patients with T2D and 1080 controls selected from the Latvian Genome Data Base (LGDB). We confirmed association of SNPs in the first intron (rs11642015, rs62048402 and rs9939609) of FTO and rs7561317 representing the TMEM18 locus with T2D. Association between SNP in FTO and T2D remained significant after c…

First Report on the Latvian SARS-CoV-2 Isolate Genetic Diversity

2021

Remaining a major healthcare concern with nearly 29 million confirmed cases worldwide at the time of writing, novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused more than 920 thousand deaths since its outbreak in China, December 2019. First case of a person testing positive for SARS-CoV-2 infection within the territory of the Republic of Latvia was registered on 2nd of March 2020, 9 days prior to the pandemic declaration by WHO. Since then, more than 277,000 tests were carried out confirming a total of 1,464 cases of coronavirus disease 2019 (COVID-19) in the country as of 12th of September 2020. Rapidly reacting to the spread of the infection, an ongoing sequenci…

The Correlation Between Abnormal Uterine Artery Flow in the First Trimester and Genetic Thrombophilic Alteration: A Prospective Case-Controlled Pilot…

2020

Introduction. Evaluation of the first trimester uterine artery flow can predict the development of obstetrical complications. A genotype, making women prone to microthrombi. constitutes the main known susceptibility factor for anomalous development of placenta. Our aim was to study whether polymorphisms of 10 genes leading to blood clotting abnormalities are related to abnormal uterine artery blood flow in the first trimester, and may predict placenta-related diseases. Material and methods. In primary analyses we included 19 singleton pregnancies with abnormal blood flow in the uterine arteries during the first trimester of gestation, and 24 matched control with normal flow patterns. All pa…

Evaluation of the Possibility to Detect Circulating Tumor DNA From Pituitary Adenoma

2019

Objective: Circulating free DNA (cfDNA) in general and circulating tumor DNA (ctDNA) in particular is becoming an increasingly used form of liquid biopsy biomarkers. In this study, we are investigating the ability to detect ctDNA from the plasma of pituitary adenoma (PA) patients. Design: Tumor tissue samples were obtained from planed PA resections, before which blood plasma samples were taken. Somatic variants found in PA tissue samples were evaluated in related cfDNA, isolated from plasma samples. Methods: Sanger sequencing, as well as previously obtained whole-exome sequencing data, were used to evaluate somatic variants composition in tumor tissue samples. cfDNA was isolated from the sa…

Nitric oxide metabolism is impaired by type 1 diabetes and diabetic nephropathy

2020

Diabetes leads to reduced nitric oxide bioavailability, resulting in endothelial dysfunction. However, overproduction of nitric oxide due to hyperglycaemia is associated with oxidative stress and tissue damage. The objective of this study was to characterise nitric oxide production (NO) and added nitrite and nitrate (NO(2)(-)+NO(3)(-)) concentration in the blood and urine of patients with and without diabetic nephropathy. A total of 268 patients with type 1 diabetes and 69 healthy subjects were included. Diabetic nephropathy was defined as macroalbuminuria and/or estimated glomerular filtration rate below 60 ml/min/1.73 cm(2). NO(2)(-)+NO(3)(-) concentration was measured by Griess reaction.…

Whole-blood transcriptome profiling reveals signatures of metformin and its therapeutic response

2020

Metformin, a biguanide agent, is the first-line treatment for type 2 diabetes mellitus due to its glucose-lowering effect. Despite its wide application in the treatment of multiple health conditions, the glycemic response to metformin is highly variable, emphasizing the need for reliable biomarkers. We chose the RNA-Seq-based comparative transcriptomics approach to evaluate the systemic effect of metformin and highlight potential predictive biomarkers of metformin response in drug-naive volunteers with type 2 diabetes in vivo. The longitudinal blood-derived transcriptome analysis revealed metformin-induced differential expression of novel and previously described genes involved in cholester…

Thiopurine

2020

Background: Thiopurine methyltransferase (TPMT) plays a significant role in the metabolism of thiopurines, and, for patients with inflammatory bowel disease (IBD), it is useful to perform TPMT genotyping prior to azathioprine (AZA) treatment. In this study, we determined TPMT gene polymorphisms in a cohort of IBD patients in Latvia. Methods: DNA samples were obtained from 244 IBD patients, and qPCR was performed for detection of rs1800462, rs1800460, and rs1142345 single-nucleotide polymorphisms (SNPs). Three common, non-functional TPMT alleles ( TPMT*2, *3B, and *3C) were identified (women, 51%; men, 49%). TPMT*2, *3A, *3B, and *3C allelic variants detected using qPCR were consistent with …

Baseline gut microbiome composition predicts metformin therapy short-term efficacy in newly diagnosed type 2 diabetes patients

2020

BackgroundThe study was conducted to investigate the effects of metformin treatment on the human gut microbiome's taxonomic and functional profile in the Latvian population, and to evaluate the correlation of these changes with therapeutic efficacy and tolerance.MethodsIn this longitudinal observational study, stool samples for shotgun metagenomic sequencing-based analysis were collected in two cohorts. The first cohort included 35 healthy nondiabetic individuals (metformin dose 2x850mg/day) at three time-points during metformin administration. The second cohort was composed of 50 newly-diagnosed type 2 diabetes patients (metformin dose-determined by an endocrinologist) at two concordant ti…

OP21.08: Genetic predisposition of pre-eclampsia and changed flow in uterine artery basin

2018

P826 Unexplained higher frequency of mutant thiopurine S-methyltransferase genotypes in inflammatory bowel disease patients of Latvia population

2019

Angiopoietin 2 and Neuropeptide Y are Associated with Diabetic Kidney Disease in Type 1 Diabetes Mellitus

2020

Abstract Background Serum angiopoietin 2 levels have been associated with endothelial dysfunction and diabetic kidney disease. Derangements in autonomous nervous system lead to increased production of vasoconstrictory and angiogenic mediators such as norepinephrine and neuropeptide Y and are associated with increased risk of microvascular complications. Aim To investigate associations between angiopoietin 2, neuropeptide Y and diabetic kidney disease in patients with type 1 diabetes mellitus. Methods 289 patients with type 1 diabetes mellitus duration > 1 year were included. Patients were stratified according to presence of diabetic nephropathy (macroalbuminuria, estimated glomerular fil…