Analysis of C9orf72 repeat expansions in Georgian patients with Amyotrophic lateral sclerosis (ALS)

Background

Amyotrophic lateral sclerosis (ALS) is a fatal progressive neurodegenerative disorder that affects the upper and lower motor neurons. Several genetic risk factors have been identified in the past decade with a hexanucleotide repeat expansion in the C9orf72 gene being the most significant. However, the presence of C9orf72 repeat expansion has not been examined in the Transcaucasian region, therefore we aimed to analyse its frequency in Georgian patients with ALS.

Methods

We included 64 self-reported Georgian patients with ALS from different parts of the country, fulfilling the Gold Coast criteria. To investigate the presence of an expanded GGGGCC hexanucleotide repeat in the non-coding region of the C9orf72 gene, we performed Repeat-Primed PCR (RP-PCR).

Results

In total, 62 sporadic and two familial ALS cases were identified. Patients were aged 26 to 84 years with a mean age of 58.3 years at disease onset. Bulbar onset was observed in 21.88%, upper limb onset in 34.38%, and lower limb onset in 43.75% of the patients. Frontotemporal dementia (FTD) fulfilling the Strong criteria was diagnosed in seven patients (10.94%). C9orf72 repeat expansion was detected in only one case using RP-PCR; the patient had a family history of dementia.

Conclusions

Our results indicate that C9orf72 hexanucleotide expansion does not belong to the major genetic risk factor of ALS in Georgian patients. Further genetic studies in a bigger study population are needed to reveal the genetic causes of ALS in the Transcaucasian population.

Association Between Multiple Single Nucleotide Polymorphisms in Folate Metabolism Pathway and Breast Cancer Risk in Georgian Women: A Case-Control Study

Background

The folate metabolism pathway plays an integral part in DNA synthesis, methylation, and repair. Methylenetetrahydrofolate reductase (MTHFR) and methylenetetrahydrofolate dehydrogenase (MTHFD1) are both enzymes that are involved in this pathway, and the single nucleotide polymorphisms (SNPs) in genes coding for them have modulatory effects on DNA expression. This study aimed to investigate the relationship between MTHFR C677T (rs1801133) and MTHFD1 G1958A (rs2236225) polymorphisms and the risk of developing breast cancer in Georgian women.

Methods

A case-control study was performed examining the MTHFR C677T and MTHFD1 G1958A SNP in breast cancer-confirmed cases and healthy matched controls. Real time-polymerase chain reaction (PCR) was used to genotype SNPs. The case individuals' pathology reports were obtained following surgeries for cancer characteristic data. Statistical analysis was performed to investigate the significance of the acquired data.

Results

Statistical analysis of MTHFR C677T SNP revealed that the CT genotype increased the risk of breast cancer by 2.17 folds in the over-dominant model. Statistical analysis of MTHFD1 G1958A SNP showed that the GA genotype increased the risk of breast cancer by 4.12 folds in the codominant model and 2.41 folds in the over-dominant model. No statistically significant link was found between genotypes and lymph node status, however, patients with the CT genotype had higher percentages of proliferative activity.

Conclusions

Breast cancer seems to have a statistically significant association with the CT genotype in MTHFR C677T and the GA genotype in MTHFD1 G1958A in Georgian women.

A founder COL4A3 pathogenic variant resulting in Alport syndrome and thin basement membrane disease: a case report series

Alport syndrome is a rare genetic condition characterized by kidney disease, hearing impairment, and ocular abnormalities. It exhibits various inheritance patterns involving pathogenic variants in COL4A3, COL4A4, and COL4A5 genes. The phenotypes can range from isolated hematuria with a non-progressive or very slowly progressive course to progressive kidney disease with extrarenal abnormalities. Timely diagnosis of Alport syndrome facilitates the early and effective implementation of treatment, as well as genetic counseling. Here, we report the COL4A3 c.765G > A, p.((=)) mutation in three ethnically Azerbaijani, apparently unrelated, consanguineous families from the village of Algeti in the Marneuli region of Georgia. We speculate that this variant could represent a founder mutation within this population and recommend offering genetic testing to Algeti village residents with persistent hematuria.

IL-10 Polymorphism and Breast Cancer Risk in Georgian Women: A Case-Control Study

Background  Interleukin-10 (IL-10) is a cytokine with a vast variety of functions, but its role in cancer development and progression is not yet clear. It is involved in two of the hallmarks of cancer: vascularization and immune modulation. IL-10 inhibits angiogenesis and hence is antitumorigenic. But it also can suppress the immune system and be tumorigenic. Objective  Evaluating the role of IL-10 (-1082 A/G) gene promoter single-nucleotide polymorphism (SNP) in breast cancer susceptibility and progression in Georgian women. Methods  A case-control study was performed on a total of 128 women, with 64 of them being histologically confirmed to have breast cancer and 64 healthy controls. SNP genotyping was performed with TaqMan assay with real-time polymerase chain reaction. And pathology report, containing proliferative activity and breast cancer hormonal status, was obtained after surgery of the case individuals. Statistical analysis was done to investigate the significance of data obtained from genotyping and histology reports. Results  Statistical analysis revealed that the difference in frequency of genotypes was not statistically significant between cases and controls (chi-square = 0.5812, p  = 0.7478). The comparison of proliferative activity of cases with AA genotypes and AG/GG genotypes showed no statistical difference ( t  = 0.2575, p  = 0.7980). Although when put into a plot (box and whiskers), patients with AG/GG genotype have outliers with very high proliferative activity. Conclusion  This study shows that -1082 A/G SNP in the promoter region of the IL-10 gene is not associated with breast cancer risk in Georgian women.

Additional evidence on the phenotype produced by combination of CFTR 1677delTA alleles and their relevance in causing CFTR-related disease

Cystic fibrosis is the most common, life-threatening, autosomal recessive disease in the Caucasian population. It is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene, which encodes a chloride ion channel expressed on the surface of epithelial cells. There are more than 2000 variants of the cystic fibrosis transmembrane conductance regulator gene reported worldwide. Some of these variants cause classic cystic fibrosis, while others are labeled as variants of unknown significance or variants of varying clinical consequences alleles and associated with atypical disease or cystic fibrosis transmembrane conductance regulator-related disorders. Although these alleles do not directly cause cystic fibrosis, they may predispose compound heterozygous patients to certain clinical phenotypes. Specifically, 1677delTA has been reported as a pathogenic allele in homozygous state or in combination with other cystic fibrosis-causing alleles. However, the L997F allele is considered to be benign or causative of non-classic cystic fibrosis or cystic fibrosis transmembrane conductance regulator-related disorders in combination with other pathogenic alleles. In this case series, we describe three cases with 1677delTA and L997F genotype, and speculate that a co-concurrence of these two alleles in trans does not cause classic cystic fibrosis symptoms; however, because the late-onset of cystic fibrosis is possible in the presence of rare alleles, such as L997F, longer follow-up of these patients and identification of a greater number of adults with 1677delTA/L997F genotype are necessary to make final conclusion about the nature of this genotype.

RISK FACTORS OF AMYOTROPHIC LATERAL SCLEROSIS IN GEORGIA

Objective - to identify risk factors in patients diagnosed with Amyotrophic Lateral Sclerosis in Georgia directed to The First University Clinic of TSMU and P. Sarajishvili Institute of Neurology. Totally 53 patients, aged 24 to 82 years, were investigated with Amyotrophic Lateral Sclerosis (ALS), defined by "Gold Coast " criteria. We have used the Questionnaire for Environmental Exposures, Toxins, and Neurological diseases developed by Dartmouth-Hitchcock Medical center to identify risk factors, and categorized patients according to the place of settlement and environmental hazards. The control consisted of age and sex matched 50 healthy individuals. The brain was visualized by MRI (1.5T), and Electromyography (EMG) was performed on all patients. ALS risk was higher among those ever holding a job in mechanics, painting, or construction (p<0.05), head trauma or concussion that caused a "blackout" or loss of consciousness was associated with a higher risk of ALS (p<0.01). Demographically more ALS cases were found in Tbilisi and Imereti, compared to other regions (p<0.05). According to our research on Georgian ALS cases, several occupational jobs, Head trauma is associated with developing ALS in Georgia, Research is needed to identify environmental risk factors attributing to higher rates of ALS in Tbilisi and Imereti.

DNA methylation status of interspersed repetitive sequences in patients with migraine

OBJECTIVE

To analyse the methylation status of the Long Interspersed Nuclear Element-1 (LINE-1) and Short Interspersed Nuclear Element Alu (Alu) of peripheral blood mononuclear cells (PBMCs) from patients with migraine compared with healthy control subjects.

METHODS

This case-control study recruited patients with migraine without aura and age-matched healthy control subjects. PBMCs were purified from peripheral blood samples. Methylation levels and patterns of LINE-1 and Alu sequences were evaluated using combined bisulfite restriction analysis-interspersed repetitive sequences polymerase chain reaction.

RESULTS

A total of 84 patients with migraine and 82 age-matched healthy controls were enrolled in the study. High levels of unmethylated cytosines in both the LINE-1 and Alu repetitive elements were observed in the migraine group compared with the control subjects. In addition, a significant difference was detected in the methylation level of LINE-1 between TT and CC genotype groups of the methylenetetrahydrofolate reductase gene.

CONCLUSIONS

These results suggest that analysis of epigenetic biomarkers in PBMCs may help to identify patients at a higher risk of migraine development.

Genotype-phenotype correlations of cystic fibrosis in siblings compound heterozygotes for rare variant combinations: Review of literature and case report

Here, we describe a cystic fibrosis (CF) family with affected siblings, two of whom have a combination of I1234V and 1677delTA variants with classic CF features, the third child with a combination of I1234V and L997F variants with atypical CF, and the apparently healthy mother with a combination of 1677delTA and L997F alleles. Interestingly, the sibling with I1234V and L997F variants had normal sweat test results and had a much milder phenotype than the other two siblings with I1234V and 1677delTA variants, suggesting that this combination is causative for atypical CF. The fact that their mother with the combination of 1677delTA and L997F appears to be healthy suggests that the L997F variant causes different phenotypes in different allele combinations. The current cases show that there is a genotype-phenotype correlation in this disease and underline the importance of genotyping individuals with suspected CF to allow prediction of disease severity and effective treatment.

First case report of Nager syndrome patient from Georgia

Nager syndrome (MIM #154400) is a rare acrofacial dysostosis syndrome predominantly characterized by malformations in craniofacial and preaxial limb bones. Most cases are sporadic and present with significant clinical heterogeneity. Although autosomal recessive and autosomal dominant modes of inheritance have been reported, most cases of Nager syndrome are spontaneous. Heterozygous variants in SF3B4 on chromosome 1q21 are found in approximately 60% of patients. Here, we report a first patient from Georgia diagnosed with Nager syndrome with detailed description of its clinical manifestations and diagnosis.

CLINICAL CHARACTERISTICS OF ALS IN GEORGIAN PATIENTS

Amyotrophic Lateral sclerosis (ALS ) is a fatal progressive neurodegenerative disease that affects the upper and lower motoneurons. .The disease is characterized by a plethora of neurological symptoms. There is a lot of information in the medical literature about ALS phenotypes, but the clinical diversity of ALS has not been studied in the Caucasus region and a unified clinical picture has not been conclusively established. In this regard, it is very important to study the symptoms among patients with ALS in Georgia. From 2018 to 2021, we examined 47 patients with ALS living in Georgia from different parts of the country, 23 - female, 24 - male, diagnosed based on clinical picture, electromyographic studies (AWAJI) and who met the EL ESCORIAL -Revised criteria. Also clinical symptom studies were conducted using the Mayo Clinic Laboratory Neurological Questionnaire. Cognitive changes were assessed using Addenbrooke's Cognitive Examination scale (ACE III) and the Frontal Behavioral Questionnaire, the patient's quality of life was assessed by ALSFRS-R. Patients were 26 to 84 years old, the age of onset of the disease was 58-60 years in men, 55-57 years in women. The bulbar type was observed in 21.3%, the upper limb type in 38.3% and the lower limb type in 40.4%. Frontotemporal dementia (FTD), diagnosed in 6 patients (12.7%). No reliable correlation was found between the forms of ALS and FTD. The results of the study showed that ALS is a multisystem disease and is not limited to damage to motoneurons. It is safe to say that ALS has characteristics of polysystemic degeneration, with the predominance of motorneuron damage. Therefore, we consider it advisable to screen all patients with ALS for additional symptoms with a focus on the examination of cognitive function, which ensures the proper management of the disease in the future.

Public attitudes towards the genetic testing in Georgia

The aim of this study is to assess attitudes towards genetic testing in Georgian public. We used a Likert-scale written questionnaire. The survey was completed by 480 respondents. A majority of respondents (75.3%) curious about predictive genetic testing and 40.6% of participants preferred to be tested only for disorders that are treatable or preventable. Approximately 65% of the participants would like to test their newborn children for late-onset disorders and undergo preconception carrier screening (73%). In addition, the majority (59%) of our respondents were not worried that genetic testing would further stigmatize people with disabilities. These results indicate that the respondents surveyed in our study may have placed particularly high importance on the availability of genetic testing and greatly valued access to genomic information.

Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms in Georgian Females with Hypothyroidism

The aim of this study was to investigate the frequency of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms in Georgian females with hypothyroidism. Thirty-four patients and 29 healthy individuals were recruited in this study. Polymerase chain reaction-restriction fragment length polymorphism analyses were used for genotyping of MTHFR polymorphisms. The results of this study suggest that the MTHFR C677T variant was significantly associated with hypothyroidism. In addition, in individuals with T allele risk of hypothyroidism significantly increased. Combination of CT/AA genotypes was more prevalent in the hypothyroid patients than in the control group. Thus, C677T polymorphism could be a possible genetic factor contributing to the pathophysiology of hypothyroidism, possibly through hyperhomocysteinemia.

ASSESSMENT OF THE VALUE OF METHYLATION FEATURES IN DIFFERENT TISSUES FOR PREOPERATIVE IDENTIFICATION OF HIGH-RISK BREAST TUMORS

Epigenetic changes in breast cancer patients have long been believed to be a promising marker for clinical management - early detection, prognostication, etc. Various approaches are available to test global DNA or target gene methylation status. We used some of them in different tissues of patients with breast cancer to analyze possible links between epigenetic parameters and their value for predicting clinicopathological characteristics (most importantly stage and lymph node status) of tumors. Patients with ductal and lobular invasive carcinoma were included in the study along with age-matched controls. Blood, tumor tissue and normal breast ductal epithelial cells were investigated using MS-HRM technique (for BRCA1 gene promoter methylation assessment), COBRA-PCR (for Alu element methylation quantification) and ELISA-based method (for global DNA methylation estimation). These parameters were analyzed in comparison to clinical, histologic and phenotypic characteristics of the tumors. BRCA1 promoter methylation was detected exclusively in tumor tissues and in only two cases, both of which had aggressive phenotype. Alu and global DNA methylation showed markedly low levels in all tissues of cancer patients compared to healthy controls, with extreme hypomethylation in tumor tissue. Changes in these two parameters were not always concordant. Methylation levels detected in blood showed rather weak relationship with clinicopathological characteristics of tumors. We could conclude that tested parameters are not useful for preoperative determination of tumor stage or lymph node status, neither any other clinicopathological characteristics of tumors. Epigenetics signatures of different tissues of the same patient are not homogenous. Given the uniform picture of DNA methylation in blood in some of investigated groups, additional data and very careful approach are required when considering using it as a diagnostic or predictive tool.

LINE-1 METHYLATION IN BLOOD AND TISSUES OF PATIENTS WITH BREAST CANCER

Methylation is an epigenetic alteration proved to be involved in many disease processes including cancer. This change affects mainly gene promoters and repetitive sequences in genome. Long Interspersed Nuclear Element-1 (LINE-1) is a family of retrotransposons - repetitive elements that modify gene activity and can themselves be targeted by epigenetic mechanisms. LINE-1 methylation level is a surrogate marker for global methylation. In many conditions this parameter is found to be altered not only in affected cell groups, but also throughout other tissues. The aim of our study was to compare LINE-1 methylation pattern in DNA extracted from blood of the patients with benign and malignant breast tissue. In addition, we investigated correlation of LINE-1 methylation in blood and tissues of same patients and relationship of all variables with histopathologic and phenotypic characteristics of tumors. Patients with biopsy-proved ductal invasive carcinoma of breast and no preoperative chemo/radiotherapy were chosen for the study group. Another pool of patients with various benign breast lesions represented controls. Blood samples from both group members were collected preoperatively. Tumor tissue sections were processed for pathology report and part of remaining tissue was used for methylation study. LINE-1 methylation level was quantified using ELISA-based assay. It was analyzed in combination with histologic and phenotypic tumor parameters and compared between different tissues and different study groups. LINE-1 was found to be significantly hypomethylated in breast cancer tissue compared to blood. Blood samples of patients with malignant tumors showed slightly lower methylation level, than samples obtained from control group members. Lymphovascular invasion was the only aggressiveness-determining factor that was found to be at least weakly correlated with LINE-1 hypomethylation in blood. We can conclude, that global hypomethylation measured by LINE-1 methylation level is significant in tumor tissue. But there is no significant difference between LINE-1 methylation levels in blood of patients with benign and malignant breast tumors; therefor LINE-1 hypomethylation in blood cannot be used as a marker for early tumor detection. Neither is it valid for determination of tumor behavior.

ALTERATION IN THE CYTOKINE SECRETION PATTERN IN T CELLS OF PATIENTS WITH CYSTIC FIBROSIS CAUSED BY DNA METHYLTRANSFERASE INHIBITOR 5-AZACITIDINE

Cystic fibrosis (CF) is the autosomal-recessive disorder caused by mutation in the cystic fibrosis transmembrane conductance regulator gene (CFTR). The Airway inflammation plays a central role in the progression of CF disease. Cystic fibrosis characterized by the overproduction of the pro-inflammatory cytokines and reduced expression of anti-inflammatory cytokines. Although the mechanisms of abnormal cytokine expression is still poorly understood, altered epigenetic regulations in T cells might contribute. In the present study we examined the expression of IFN-γ and IL-10 by CF T cells prior to and following 5-azaC treatment. In addition we investigated DNMTs levels in nuclear extracts of CD4+ T cells derived from CF and non-CF individuals. Seven CF patients (age: 5-12 years) were included in the study and compared to six age-matched healthy subjects (age: 6- 13 years). CD4+ T cells were isolated from PBMC using CD4 MicroBead kit (Miltenyi Biotec GmbH) and were cultured in RPMI 1640 medium at 37°C with 5% CO2, in presence or absence of 5-azacytidine. Concentrations of IL-10 and γ-INF in CD4+ T Cells were measured by ELISA (eBoiscience, san Diego, CA, USA). In our study we showed that 5 Azacytidine alters nuclear levels of DNMT 3a as well as modulates cytokine levels in CD4+ T cells derived from CF patients. After 5-azaC treatment secretion of IFN-γ was significantly decreased in CF T cells, while amount of IL-10 was elevated by ~2.5 times compared to untreated controls (P<0.05). In summary, data presented in this report demonstrates that epigenetic mechanisms such as DNA methylation may be considered as a one of the potential therapeutic target in a treatment of Cystic Fibrosis.

MTHFR GENE C677T POLYMORPHISM AND LEVELS OF DNA METHYLTRASFERASES IN SUBCLINICAL HYPOTHYROIDISM

The aim of our study was to investigate the link between MTHFR gene C677T polymorphism and DNMTs levels in patients with Subclinical Hypothyroidism (SCH). In this study 19 adult patients with subclinical hypothyroidism and 19 healthy controls (mean age 31±5.5 and 33±5.1 years respectively) were recruited. All patients were diagnosed based on serum levels of TSH, FT4, anti-TG and anti-TPO antibodies. Written informed consents were obtained from all study subjects. Genomic DNA was extracted using Quick-DNA Universal Kit (Zymo Research, USA). The MTHFR C677T polymorphism was genotyped by PCR-RFLP method. Levels of DNMT1 and 3a were measured in nuclear extracts of PBMC using DNMTs assay kits (Abcam). Our data indicates that the frequency of genotypes and alleles were different among the patient and the control group. There is a significant increase in CC genotype distribution in the control group when compared to the SCH patient group, while the CT as well as TT genotype distribution were not increased significantly in SCH group versus control group. However the C allele is significantly prevalent in the control group compared to the SCH group, while T allele is prevalent in patients compared to the control group with a statically significant difference. In addition, individuals with TT and CT genotypes and hypothyroidism showed elevated amount of DNMT3a in nuclear extracts of PBMC compared with controls, while no significant difference in DNMT1 levels was observed. This study indicates the MTHFR C677T variant may contribute in alteration of epigenetic regulation such as DNA methylation mediated by DNA methyltransferases in patients with subclinical hypothyroidism and also, carriers of the T allele might have an increasing risk of developing SCH.

A STUDY OF THE RELATIONSHIP BETWEEN LEVELS OF METHYLTRANSFERASES IN PERIPHERAL BLOOD MONONUCLEAR CELLS AND CHARACTERISTICS OF TUMOR IN PATIENTS WITH DUCTAL INVASIVE CARCINOMA OF BREAST

The role of epigenetics in tumor development and progression is actively being studied. The aim of our current pilot study is to analyze correlation of changes in the levels of methyltransferases in nuclear extracts of blood cells with some morphological and phenotypic characteristics of breast cancer. The levels of DNMT1, DNMT3a and H3K4 methyltransferase were measured. The results showed that the level of DNMT1 was highest in the control group but correlation with the tumor grade was just moderate. DNMT3a was found in highest level in Grade III cancer group, followed by Grade II and Grade I groups. Correlation of DNMT1 level with tumor grade was moderate. An opposite pattern was seen for H3K4 methyltransferase. DNMT3a level was higher in larger tumors, while the level of H3K4 methyltransferase was lowest in large tumors with significant negative correlation with the tumor size. This primary study shows that there are some changes in methyltransferase levels in PBMC from breast cancer patients. These changes are most probably attributed to modification of initiation as well as sustainment of methylated status of products.

Epigenetic regulation of acute inflammatory pain

Acute pain is associated with tissue damage, which results in the release of inflammatory mediators. Recent studies point to the involvement of epigenetic mechanisms (DNA methylation) in the development of pain. We have found that during acute inflammatory pain induced by the application of 10% mustard oil on the tongues of rats, levels of DNMT3a and 3b were elevated markedly (36 and 42 % respectively), whereas the level of DNMT1 was not changed significantly. Previous injection of Xefocam with 0,4 mg/kg dose decreased levels of DNMT3a and 3b (25 and 24% respectively). The level of DNMT1 was not changed significantly compared to the control group. The findings support the idea that inhibitors of DNA-methyltransferases could be useful for pain management. Our data suggest that NSAIDs (alone or in combination with DNMT inhibitors) may be proposed as possible epigenetic regulatory agents, which may play a role in epigenetic mechanisms indirectly through altering the activity of inflammatory mediators involved in pain development.

Expression pattern of DNA-methyltransferases and its health implication (short review)

Epigenetics is heritable and reversible alterations of gene expression without direct alteration of DNA sequences. One example of epigenetic factors is DNA methylation, which prevents certain genes from being expressed. Another example is histone modifications. In addition, miRNAs can silence genes at transcriptional and posttranscriptional level. DNA methylation is regulated by DNA methyltransferases (DNMT1, DNMT3a, and DNMT3b). Aberrant DNMTs expression is the dominant mechanism for the genome instability which associates with a wide range of diseases such as a cancer, autoimmune diseases, mental disorders. In this article we reviewed the major mechanisms of changes of DNA methylation regulated by DNMTs and the role of this changes in pathogenesis of various diseases. In addition we briefly reviewed epigenetic agents, such as inhibitors of DNA methyltransferases or HDAC (histone deacetylase) targeting oncology, hematology, immunology, and neurologic disease indications, and which are in various phases of study or have been clinically tested and approved by FDA (Food and Drug Administration).

Rare tubulopathy - primary hypophosphatemic rickets (case report)

Primary hypophosphatemic rickets is a rare disorder caused by inborn defect of renal tubular reabsorbtion and usually manifested in childhood and infancy with stunted growth and deformities of lower limbs. Patient 12 years old, female, was born to healthy parents, at 41 weeks of gestation by normal delivery and had a normal birth weight and length. She had one healthy sibling (male). Psychomotor development until the age of 2 years was normal. Since the age of 2 years deformation of legs and difficulties with walking have been observed. The Patient was consulted by Pediatric Orthopedist, Nephrologists and Endocrinologist. The blood biochemical findings revealed normal pH, normal calcium (CA), potassium (K), sodium (Na) concentrations, very low phosphate (P) with markedly elevated alkaline phosphatase (AP) and slightly elevated parathyroid hormone (PTH) concentration; urine test indicated impaired tubular function: mild glucosuria, proteinuria, and markedly increased phosphaturia. Phosphate tubular reabsorbtion (PTR) was 52%, phosphate/creatinine clearance 0,52, renal threshold phosphate concentration (TmP/GFR) 0,25 mmol/l. Genetic tests results not available yet.

RESULTS

the diagnosis of phosphate diabetes made on the basis of clinical-laboratory data. The therapy with Inorganic phosphate (50-100mg/kg/d) and 1,25(OH)D3 40-50 ng/kg/d had been started. Childs walking abilities improved with treatment, the deformation of legs decreased, but O-legs and other skeletal deformations are still remarkable. Auxological parameters are not satisfactory. Physical growth is below the normal range (height SDS -3,78); the patient's predicted height less than target height. Biochemical monitoring performed regularly under the treatment, serum phosphate remains below normal, serum ALP is still elevated.

CONCLUSION

This case is in line with other publications and indicates the difficulty to achieve normal phosphate levels and normal growth without an additional treatment with growth hormone. At this stage of the disease, the question of referring to the growth hormone therapy is being considered aimed to improve the growth tendencies. It is possible that orthopedic surgery is also needed in the future.

N-methyl-D-aspartate and sigma-ligands change the production of interleukins 8 and 10 in lymphocytes through modulation of the NMDA glutamate receptor

Human T lymphocytes express both ionotropic and metabotropic glutamate receptors that control immune responses, cell activation, maturation and death. In this study, we examined the effect of N-methyl-D-aspartate (NMDA) and sigma1-receptor ligands on the secretion of the proinflammatory chemokine interleukin 8 (IL-8) and the anti-inflammatory cytokine interleukin 10 (IL-10) in human leukemia Jurkat cells and peripheral blood lymphocytes (PBLs). We have shown that NMDA increased IL-8 and decreased IL-10 secretion and that sigma-ligands modulated the action of NMDA. Moreover, the effects of NMDA and sigma-ligands were interrelated with the nitric oxide (NO) content, suggesting that the intracellular concentration of NO could play a major role in the synthesis of cytokines. Western blots against the NR2A and NR2B subunits of the NMDA glutamate receptor revealed that long-term (48 h) treatment of PBLs with glutamate at concentrations within normal plasma levels (1 x 10(-5)M), in contrast to low concentrations (0.3 x 10(-6)M), downregulates the NR2A subunit, probably by internalization. Furthermore, we found that PBLs with noninternalized NR2A secreted less IL-10 than lymphocytes with downregulated NR2A; under these conditions, the transcriptional activity of NF-kappaB was increased whereas the transcriptional activity of c-Fos was decreased. These findings implicate that the activities of NF-kappaB and c-Fos control the expression of the IL8 and IL10 genes, depending on the subunit composition of the NMDA receptor. In conclusion, we suggest that lymphocytes express an active NMDA receptor only in a low-glutamate milieu.

Glutamate decreases the secretion of IL-10 by peripheral blood lymphocytes in persons with autoimmune thyroiditis

Human T lymphocytes expose ionotropic and metabotropic glutamate receptors, which control immune responses, cell activation, maturation, and death. Several cytokines release during inflammation which identification may have important physiological and clinical implications. Main biological function of IL-10 is limitation and termination of inflammatory responses and the regulation of differentiation and proliferation of several immune cells. Various inflammatory molecules regulated the secretion of IL-8 and IL-10, but the action of glutamate on the biosynthesis of cytokines is unknown. We have found that in peripheral blood lymphocytes glutamate at the concentrations within normal plasma levels (1 x 10(-5) M), as well as at lower concentration (0.3 x 10(-6) M) changes the secretion of immunosuppressive cytokine IL-10, whereas synthesis of proinflammatory chemokine, IL-8 did not changed significantly. Moreover, our results have shown that peripheral blood lymphocytes from patients with autoimmune thyroiditis release less IL-10 at both concentration of glutamate than peripheral blood lymphocytes from healthy persons. These data suggest that glutamate decrease the secretion of IL-10 by peripheral blood lymphocytes, especially in patients with autoimmune thyroiditis that may be responsible for prolongation of inflammation.

Growth hormone (GH) determinations by RIA and IFA during GH stimulation tests in children with short stature

Growth hormone deficiency (GHD) as a syndrome comprises multiple pathogenetically distinct entities caused by disorders of secretion or peripherial action of growth hormone (GH). Confirmation of the diagnosis of GH deficiency in children is based on provocative testing for human growth hormone (hGH). Immunofunctional assay (IFA) allows quantitation of only biological active GH forms in circulation. The aim of this study was to compare the results of GH determinations by radioimmunoassay (RIA) and IFA, and to establish cut-off-levels for IFA in insulin tolerance test (ITT). We have investigated 32 children (30 males and 2 females) with short stature. All patients underwent insulin tolerance test (ITT), GH was measured in duplicate by radioimmunoassay (RIA, Seria) and IFA (DSL). Children with peak GH concentration below 10 ng/ml in ITT (by RIA) underwent arginin tolerance test (ATT, arginin 0,5 g/kg). The correlation between the results of growth hormone determination by radioimmunoassay and immunofunctional assay was excellent and cut-off-level in stimulatory test was established for the immunofunctional assay.