AMPD1 Research Articles

The Single Nucleotide Variant rs17602729 (C34T) of the <i>AMPD1</i> Gene is Associated with Athletic Qualification and Competitive Distance in Caucasian Cyclical Sports Athletes

All physiological processes necessary for high athletic performance, including energy production in skeletal muscles and the peculiarities of metabolic processes (phosphogenic pathway, glycolytic, aerobic) are genetically determined. The enzyme Adenosine Monophosphate Deaminase is an important regulator of skeletal muscle energy metabolism during exercise. The identification of genetic biomarkers that determine the effectiveness of ATP resynthesis is one of the priorities of sports genetics. (1) Background: To study the associations of SNV rs17602729 (C34T) allelic variants and genotypes of the AMPD1 gene with qualification and competitive distance in Caucasian athletes of the Southern Urals. (2) Methods: 173 people of European origin who lived in the Southern Urals region took part in the study. The first group included 123 cyclical sports athletes (speed skating, running disciplines in track-and-field): SD (short distances) subgroup ‒ 40 sprinters (mean - 22.1 ± 2.4 y.o.); MD (middle distances) subgroup ‒ 38 athletes (mean - 20.1 ± 2.5 y.o.); subgroup LD (long distances) – 45 stayer athletes (mean - 22.6 ± 2.7 y.o.). The control group consisted of 50 healthy non–athletes (mean ‒ 21.4 ± 2.7 y.o.). We used the Step One Real-Time PCR System (Applied Biosystems, USA) device for real-time polymerase chain reaction. (4) Conclusions: the common allele with rs17602729 of the AMPD1 gene can be considered as a biomarker associated with short and medium competitive distances. It can help in the selection of elite athletes who require effective performance of anaerobic sports loads. The variable T allele is an unfavorable biomarker (negative predictor) for achieving the status of Honored Master of Sports and Sport Master of International Class in athletics and speed skating, regardless of the competitive distance.

Genes Associated with Muscle, Tendon and Ligament Injury Epidemiology in Women’s Amateur Football Players

Background: There is a lack of specific genetic studies regarding injuries in women’s football. However, different genetic factors have been associated with tendon/ligament injuries in women football players. The aim of the study was to examine the genotypic frequencies of genes associated with injury risk and epidemiology in women’s amateur football players and the aetiology of injuries. Methods: In total, 168 women’s amateur football players from football clubs in the Spanish second division league and Caucasian descent were enrolled in this prospective observational cross-sectional study. AMPD1 (rs17602729), ACE (rs4646994), ACTN3 (rs1815739), CKM (rs8111989) and MLCK (rs2849757 and rs2700352) polymorphisms were genotyped. The characteristics of 169 non-contact injuries during the 2022/2023 season were classified following the International Olympic Committee (IOC) Consensus Statement for reporting injuries as follows: musculoskeletal, tendon/ligament, injury setting; and severity. The disequilibria of polymorphisms were estimated using the Hardy–Weinberg Equilibrium (HWE). The characteristics of the injuries were recorded, and the genotype characteristics were analysed. The genotype frequencies of all polymorphisms were compared between non-injured and injured football players and injury aetiologies. Results: The AMPD1 genotype distribution differed between tendon/ligament injured and non-injured (p = 0.003) with a higher frequency in the TT genotype and T allele. The genotype distribution was different for the CKM and MLCK c.37885C>A polymorphisms in training and match injuries (p = 0.038 and p = 0.031, respectively). In the ACTN3 and AMPD1 polymorphisms, the distribution of the TT genotype in both genes showed a higher frequency in severe injuries (all p < 0.001). Conclusions: Tendon/ligament injury epidemiology in women’s amateur football players was associated especially with the TT genotype of the AMPD1 gene. The TT genotype of the AMPD1 and ACTN3 genes was also associated with severity, and the CKM and MLCK polymorphisms were associated with injury settings.

Analysis and Validation of the Prognosis ability of the M7GRelated miRNAs in Lung Adenocarcinoma.

N7-methylguanosine (m7G) modification plays a crucial role in the development and progression of lung cancers. MicroRNAs (miRNAs) are closely involved in programmed cell death and the mechanism of tumor growth. The m7G-associated miRNAs genes in lung adenocarcinoma (LUAD), and their prognosis prediction ability of LUAD, however, had not been investigated. The RNA transcriptomes, clinical indices, and immune scores of LUAD patients were searched and downloaded from The Cancer Genome Atlas (TCGA) and the ESTIMATE database. The miRNAs targeting METTL1 and WDR4 were extracted from the TargetScan database. Differentially expressed m7G-related miRNAs were identified and their prediction power of LUAD prognosis was systematically investigated. Among 40 the differentially expressed m7G-related miRNAs in LUAD, five (hsa-miR-31-5p, hsa-miR-5571-3p, hsa-miR-4697-3p, hsa-miR-6858-5p, and hsa-miR-873-3p) demonstrate significant predictive value for prognosis. The risk score constructed by these five miRNAs was an independent prognostic factor (univariate Cox regression results: hazard ratio (HR) = 1.6619, 95% confidential interval (CI) = 1.2103-2.2819, p = 0.0017; multivariate Cox regression results: HR = 1.6004, 95% CI = 1.1633-2.2017, p = 0.0039). The survival curves showed that patients with high-risk scores had a poor prognosis. Calibration curves indicated good predictability in a nomogram constructed combining the miRNA and the clinical indices of age, sex, chemotherapy, radiotherapy, stage, and risk score. GO and KEGG analysis of the overlapping genes showed that the prognostic miRNAs were closely associated with the neuropeptide signaling pathway. Besides, the immune infiltration analysis showed that the expression of the AMPD1 gene was strongly associated with immune cells and immunology functions in LUAD. This study identified DE m7G-related miRNAs and demonstrated their prediction ability in the prognosis of LUAD patients. The risk signature based on these miRNAs demonstrates high accuracy in predicting the prognosis of LUAD patients.

In Silico approach for identification, prediction of AMPD1 gene nsSNPs associated with Myoadenylate Deaminase deficiency

In Silico approach for identification, prediction of AMPD1 gene nsSNPs associated with Myoadenylate Deaminase deficiency

Pontocerebellar Hypoplasia Type 9: A New Case with a Novel Mutation and Review of Literature.

Pontocerebellar hypoplasia type 9 (PCH-9) is a very rare autosomal recessive neurodegenerative disorder. Affected infants present early with severe developmental delay, spasticity, with the unique magnetic resonance imaging picture of thin corpus callosum, atrophied pons, and cerebellum. It is caused by loss of function mutations in the AMPD2 gene, encoding for the adenosine monophosphate deaminase enzyme-paralog 2. This gene is expressed in different somatic tissues with high level of expression in cerebellum and its encoded enzyme catalyzes a critical step in de novo biosynthesis of purines and its deficiency in the developing neurons severely affects neuronal differentiation and cell viability. We clinically evaluated an Emirati patient presented with severe developmental and growth delay, as well as corpus callosum agenesis and atrophy of brainstem and cerebellum. We performed exome sequencing, Sanger sequencing, and segregation analysis to identify the genetic cause of the phenotype, followed by in silico and in vitro analysis. We identified the novel variant (NM_004037.9:c.1471G > A) in AMPD2 gene leading to a single amino acid substitution (p.Gly491Arg) in adenosine monophosphate deaminase-2 enzyme. This variant is predicted to be pathogenic using several in silico tools, and resulted in a decrease in the enzyme function in the patient's polymorphonuclear cells by 82% (95% confidence interval: 73.3-91.7%, p = 0.029) compared with the control. This data establishes that the affected child is affected by PCH-9. Furthermore, we review all reported cases in literature to summarize the main clinical features of this rare disease.

Transcriptome Analysis Reveals the Differentially Expressed Genes Associated with Growth in Guangxi Partridge Chickens.

The Guangxi Partridge chicken is a well-known chicken breed in southern China with good meat quality, which has been bred as a meat breed to satisfy the increased demand of consumers. Compared with line D whose body weight is maintained at the average of the unselected group, the growth rate and weight of the selected chicken group (line S) increased significantly after breeding for four generations. Herein, transcriptome analysis was performed to identify pivotal genes and signal pathways of selective breeding that contributed to potential mechanisms of growth and development under artificial selection pressure. The average body weight of line S chickens was 1.724 kg at 90 d of age, which showed a significant increase at 90 d of age than line D chickens (1.509 kg), although only the internal organ ratios of lung and kidney changed after standardizing by body weight. The myofiber area and myofiber density of thigh muscles were affected by selection to a greater extent than that of breast muscle. We identified 51, 210, 31, 388, and 100 differentially expressed genes (DEGs) in the hypothalamus, pituitary, breast muscle, thigh muscle, and liver between the two lines, respectively. Several key genes were identified in the hypothalamus-pituitary-muscle axis, such as FST, THSB, PTPRJ, CD36, PITX1, PITX2, AMPD1, PRKAB1, PRKAB2, and related genes for muscle development, which were attached to the cytokine–cytokine receptor interaction signaling pathway, the PPAR signaling pathway, and lipid metabolism. However, signaling molecular pathways and the cell community showed that elevated activity in the liver of line S fowl was mainly involved in focal adhesion, ECM-receptor interaction, cell adhesion molecules, and signal transduction. Collectively, muscle development, lipid metabolism, and several signaling pathways played crucial roles in the improving growth performance of Guangxi Partridge chickens under artificial selection for growth rate. These results support further study of the adaptation of birds under selective pressure.

Genetic characteristics of competitive swimmers: a review.

A successful swimming performance is a multi-factorial accomplishment, resulting from a complex interaction of physical, biomechanical, physiological and psychological factors, all of which are strongly affected by the special medium of water as well as by genetic factors. The nature of competitive swimming is unique, as most of the competitive events last less than four minutes. Yet training regimens have an endurance nature (many hours and many kilometres of swimming every day), which makes it impossible to classify swimming by definitions of aerobic-type or anaerobic-type events, as in track and field sports. Therefore, genetic variants associated with swimming performance are not necessarily related to metabolic pathways, but rather to blood lactate transport (MCT1), muscle functioning (IGF1 axis), muscle damage (IL6) and others. The current paper reviews the main findings on the leading 12 genetic polymorphisms (located in the ACE, ACTN3, AMPD1, BDKRB2, IGF1, IL6, MCT1, MSTN, NOS3, PPARA, PPARGC1A, and VEGFR2 genes) related to swimming performance, while taking into consideration the unique environment of this sport.

The Effect of Different Programs of Exercise on The Expression of Genes Associated with Endurance and Energy Metabolism

Physical exercise promotes the energy metabolism of the body. While physiological changes occuring in human body after regular exercise is well defined, it is not known how the body’s response changes during the time course of the exercise. Here, we investigated how the acute and chronic exercise alters expressions of genes related to energy metabolism and endurance. Our study investigated the effects of acute and chronic exercise on the expression of genes related to energy metabolism (AMPD1, PPARA) and endurance (ADRB2). Study group; was formed with 24 people: 12 healthy females and 12 healthy males. Maximal oxygen use capacities of the participants were determined by the Bruce test protocol at the beginning and end of the 8-week training program. After calculating their maximal oxygen use capacity, each participant was given an acute running exercise on the tread mill at the speed and incline that the participant would reach to his/her maxVO2 until he/she exhausted. The same people were built to continuous runs (%50-70) once every 8 weeks, and two days of medium-term interval training program (%90-95). Peripheral blood samples were taken before and after acute exercise and immediately after chronic exercises. RNA isolation was performed using TRIzol Reagent from peripheral blood mononuclear cells. Gene expression was determined by Biomark Real-Time PCR (RT-PCR). Gene expression data was quantified by using both t-test and Mann-Whitney U tests. The statistical level of p <0.05 was taken. Our results show that ADRB2 and AMPD1 gene expression values increase in women after acute exercise. There were changes in the mean values of ADRB2, AMPD1, PPARA gene expressions in both men and women after the 8-week training program compared to pre-acute exercise. Expression of PPARA gene significantly decreased after exercise compared to pre-exercise only for the female group. This study is important in developing ideas about gene expressions of genes related to energy training and endurance with different selections and different exercise programs. Our results; this suggests that different training programs on different genders are important in terms of giving an idea about the gene expressions of genes related to energy metabolism and endurance.

Молекулярно-генетический анализ генов ACTN3 и AMPD1 у дзюдоистов спортивной школы по самбо и дзюдо «Витязь» г. Перми

The analysis of ACTN3 and AMPD1 genes polymorphisms associated with the development of speed-strength qualities for judo athletes was carried out. Overall, 71 judokas of the sambo and judo sports school “Vityaz” in Perm were tested. The heterozygous R/X genotype of the ACTN3 gene prevails with a frequency of 0.9 in the studied group. The carriers of this genotype are characterized by the average functional activity of α-actin-3. The most favorable homozygous R/R genotype, associated with the high functional activity of α-actin-3, is significantly less common (frequency of 0.1). Homozygous X/X genotype was not found in the surveyed sample. The AMPD1 gene polymorphism analysis revealed that the homozygous C/C genotype prevails with a frequency of 0,83. The genotype is favorable for the development of speed-strength qualities of athletes. The C/T heterozygous genotype occurs with a frequency of 0,17. The T/T genotype was not identified in the studied selection. Allelic variants of the ACTN3 and AMPD1 genes were analyzed in two groups of judokas with high and low qualifications A comprehensive research data analysis showed that athletes with the ACTN3 R/R and AMPD1 C/C genotypes are able to achieve outstanding sports success and sports-life longevity. These genotypes can be used as markers for determining the development of physical qualities when choosing sports specialization. Moreover, they could be helpful in predicting performance, as well as in regulating loads during training. Individual reports were compiled, trainers and athletes were given recommendations on the correction of the training process, taking into account the genetic profiles of examined athletes.

Raumenų adaptaciją prie fizinių krūvių lemiančių „CKM“ ir „AMPD1“ genetinių variantų analizė Lietuvos sportininkų grupėje

[full article and abstract in Lithuanian; abstract in English] Energy homeostasis and different muscle contraction properties demands for interactive processes of diverse specialty enzymes, including important reactions of enzymes-regulators – adenosine monophosphate deaminase 1 (encoded by AMPD1 gene) and muscle-specific creatine kinase (encoded by CKM gene), in the human body during the physical activity. This research aims to analyse the effect of CKM (c.*800A >G, rs8111989) and AMPD1 (c.133C >T, p.Gln45Ter, rs17602729) gene polymorphisms on physical capacities of Lithuanian elite athletes. The study involved 150 Lithuanian elite athletes (60 females and 90 males, Olympic candidates, World’ and European Olympic medallists) and 150 controls (60 females and 90 males, healthy unrelated citizens of Lithuania without any competitive sport experience). The athletes were prospectively stratified into three groups according to the event duration and distance, spanning a spectrum from the endurance-oriented to the power-oriented athletes: ‘endurance group’ (n = 63), ‘sprint/power group’ (n = 65) and “mixed” (n = 22), sports utilized anaerobic and aerobic energy production). Physical (anthropometric) measurements (height, weight, muscle mass and fat mass, body mass index (BMI)) and indices of functional capacity (anaerobic muscle strength based on right and left hands grip strength, short-term explosive muscle power (STEMP), anaerobic alactic muscle power (AAMP) and aerobic capacity based on maximum oxygen uptake (VO2max)) were determined for athletes. For molecular genetic analysis, DNA was extracted from blood leukocytes using standard phenol-chloroform method. Two different strategies were used for CKM and AMPD1 polymorphisms genotyping: CKM polymorphism genotyping was performedby allelic discrimination technology based real-time polymerase chain reaction and AMPD1 polymorphism – by restriction fragment length polymorphism method. Phenotypic analysis showed that mean values of physical measurements and functional capacity indices (except height, weight, muscle and fat mass) were significantly different between sport groups and were specific to each group (p G) a ndAMPD1 (c.133C>T) genetic variants have different effect on male and female physical capacity. CKM AA and AG genotype confers ability to achieve better muscle efficiency in short-term, maximum-effort requiring physical activity and AMPD1 CC genotype athletes have better aerobic capacity. Our study approves the opinion of many sports and genetic scientists that sprint and power qualities are more effected by inheritance than the endurance qualities. Keywords: creatine kinase, myoadenylate deaminase, gene polymorphisms. DOI: https://doi.org/10.15823/sm.2019.95.7

Can Genetics Predict Sports Injury? The Association of the Genes GDF5, AMPD1, COL5A1 and IGF2 on Soccer Player Injury Occurrence.

Genetics plays an integral role in athletic performance and is increasingly becoming recognised as an important risk factor for injury. Ankle and knee injuries are the most common injuries sustained by soccer players. Often these injuries result in players missing training and matches, which can incur significant costs to clubs. This study aimed to identify genotypes associated with ankle and knee injuries in soccer players and how these impacted the number of matches played. 289 soccer players, including 46 professional, 98 semi-professional and 145 amateur players, were genetically tested. Ankle and knee injuries and the number of matches played were recorded during the 2014/15 season. Four genes were assessed in relation to injury. Genotypes found to be associated with injury included the TT (nucleobase) genotype of the GDF5 gene, TT and CT (nucleobase) genotypes of AMPD1 gene, TT genotype of COL5A1 and GG (nucleobase) genotype of IGF2 gene. These genes were also associated with a decrease in the number of matches played.

Effects of AMPD1 common mutation on the metabolic-chronotropic relationship: Insights from patients with myoadenylate deaminase deficiency.

PurposeCurrent evidence indicates that the common AMPD1 gene variant is associated with improved survival in patients with advanced heart failure. Whilst adenosine has been recognized to mediate the cardioprotective effect of C34T AMPD1, the precise pathophysiologic mechanism involved remains undefined to date. To address this issue, we used cardio-pulmonary exercise testing data (CPX) from subjects with myoadenylate deaminase (MAD) defects.MethodsFrom 2009 to 2013, all the patients referred in our laboratory to perform a metabolic exercise testing, i.e. a CPX with measurements of muscle metabolites in plasma during and after exercise testing, were prospectively enrolled. Subjects that also underwent an open muscle biopsy for diagnosis purpose were finally included. The metabolic-chronotropic response was assessed by calculating the slope of the linear relationship between the percent heart rate reserve and the percent metabolic reserve throughout exercise. MAD activity was measured using the Fishbein’s technique in muscle biopsy sample. The common AMPD1 mutation was genotyped and the AMPD1 gene was sequenced to screen rare variants from blood DNA.ResultsSixty-seven patients were included in the study; 5 had complete MAD deficiency, 11 had partial MAD deficiency, and 51 had normal MAD activity. Compared with normal MAD activity subjects, MAD deficient subjects appeared to have a lower-than-expected metabolic-chronotopic response during exercise. The metabolic-chronotropic relationship is more closely correlated with MAD activity in skeletal muscle (Rs = 0.57, p = 5.93E-7, Spearman correlation) than the presence of the common AMPD1 gene variant (Rs = 0.34, p = 0.005). Age-predicted O2 pulse ratio is significantly increased in MAD deficient subjects, indicating a greater efficiency of the cardiovascular system to deliver O2 (p < 0.01, Scheffé’s post hoc test).ConclusionThe metabolic-chronotropic response is decreased in skeletal muscle MAD deficiency, suggesting a biological mechanism by which AMPD1 gene exerts cardiac effect.

Effects of AMPD1 gene C34T polymorphism on cardiac index, blood pressure and prognosis in patients with cardiovascular diseases: a meta-analysis

BackgroundThe meta-analysis was aimed to evaluate the effects of AMPD1 gene C34T polymorphism on cardiac function indexes, blood pressure and prognosis in patients with cardiovascular diseases (CVD).MethodsEligible studies were retrieved through a comprehensive search of electronic databases and manual search. Then the high-quality studies met the rigorous inclusion and exclusion criteria, as well as related to the subject was selected for the study. Comprehensive data analyses were conducted using STATA software 12.0.ResultsThe study results revealed that CVD patients with CT + TT genotype of AMPD1 C34T polymorphism presented elevated left ventricular ejection fraction (LVEF) (%) and reduced left ventricular end diastolic dimension (LVEDD) (mm) as compared with CC genotype, moreover, the subgroup analysis found that the LVEF (%) was markedly higher in heart failure (HF) patients carrying CT + TT genotype than CC genotype. Besides, the systolic blood pressure (SBP) (mmHg) in CVD patients with CT + TT genotype was obviously decreased in contrast with the CC genotype. Patients suffered from HF with different genotypes (CT + TT and CC) of AMPD1 C34T polymorphism exhibited no significant differences in total survival rate and cardiac survival rate.ConclusionsOur current meta-analysis indicated that the T allele of AMPD1 gene C34T polymorphism may be correlated with LVEF, LVEDD and SBP, which plays a protective role in the cardiac functions and blood pressure in CVD patients, but had no effects on total survival rate and cardiac survival rate for HF.

ADSL, AMPD1, and ATIC Expression Levels in Muscle and Their Correlations with Muscle Inosine Monophosphate Content in Dapulian and Hybridized Pig Species

We investigated the relationship between muscle inosine monophosphate (IMP) content and mRNA levels of ADSL, AMPD1, and ATIC in Dapulian (DPL), Landrace × Dapulian (LDPL), and Duroc × Landrace × Dapulian (DLDPL) hybridized pigs. Methods: The total RNA in longissimus dorsi was isolated from Dapulian (DPL), Landrace × Dapulian (LDPL) and Duroc × Landrace × Dapulian (DLDPL) hybridized pigs, weighed about 95.0 kg, n = 8/species. The internal genes with highest stability (YWHAZ and RPL4) were chosen from 11 common internal genes using Quantitative real-time PCR (qPCR) and geNorm software. The mRNA levels of ADSL, AMPD1 and ATIC genes were corrected with YWHAZ and RPL4 genes. The muscular IMP content was determined by HPLC. The muscular IMP content in DPL was higher than that in LDPL and DLDPL, 25.00% (p 0.05) and 15.56% (p > 0.05), respectively. The muscular mRNA level of ADSL gene in DPL and LDPL was higher than that in DLDPL, 24.14% and 12.07%, respectively (p 0.05). The muscular mRNA level of ATIC gene in DPL and LDPL was higher than that in DLDPL, 66.67% and 33.33%, respectively (p 0.05). The muscular mRNA level of AMPD1 gene in DPL and LDPL was higher than that in DLDPL, 14.49% and 33.26%, respectively. Furthermore, the IMP content was positively correlated with the mRNA level of ADSL, AMPD1 and ATIC genes, respectively (p 0.05). The mRNA level of ADSL gene was highly related to that of AMPD1 and ATIC gene, respectively (p 0.01), while that of AMPD1 gene was not strongly correlated with that of ATIC gene (p > 0.05). The muscular mRNA level of AMPD1, ADSL and ATIC genes and the muscular IMP content in DPL were highest, followed by those in LDPL and DLDPL. The muscular IMP content was positively correlated with the muscular mRNA level of ADSL, AMPD1 and ATIC genes, respectively.

Insertion of a knockout-first cassette in Ampd1 gene leads to neonatal death by disruption of neighboring genes expression.

AMPD1 is an adenosine monophosphate deaminase that catalyzes the deamination of AMP to IMP. To understand the physiological function of AMPD1, we obtained a strain of Ampd1 mutant mice from KOMP repository, which was generated by a knockout-first strategy. An elevated AMP level and almost complete lack of IMP was detected in the skeletal muscle of E18.5 Ampd1tm1a/tm1a mice. However, Ampd1tm1a/tm1a mice died in 2 days postnatally, which was contradicting to previous reports. After removal of the knockout-first cassette and critical exon, mice homozygous for the Ampd1tm1c/tm1c and Ampd1tm1d/tm1d alleles survived to adulthood. RNA-seq analysis indicated that the expression of two neighboring genes, Man1a2 and Nras, were disrupted in the Ampd1tm1a/tm1a mice, but normal in the Ampd1tm1c/tm1c and Ampd1tm1d/tm1d mice. The neonatal lethality phenotype in the Ampd1tm1a/tm1a mice was consistent with the Man1a2-deficient mice. Our results indicated the knockout-first cassette may cause off-target effect by influence the expression of neighboring genes. This study, together with other reports, strongly suggests that removal of targeting cassette by site-specific recombinases is very important for the accurate phenotypic interpretation on mice generated by target mutations.

Ability of HMGB1 protein to bind to intrinsically bent and non-bent DNA sites in the AMPD2 gene amplicon.

HMGB-like proteins are architectural chromatin factors, and their function is heavily dependent on their ability to interact with DNA (especially non-canonical DNA structures). HMGB1 is involved in many DNA processes, and dysregulation of HMGB protein expression has profound effects on cellular transcription, resulting in severe developmental defects as well as cancer. During DNA replication, elements that form the origin are still not well defined in metazoans. Sites with A (adenine) or T (thymine) repeats cause intrinsic curvatures in the DNA and are described to be involved in the replication machinery by providing binding sites to replication proteins. As a result, the DNA molecule shows intrinsically bent DNA sites, caused by periodic repeats of 2 or more As/Ts (dA/dT) as well as intrinsically non-bent DNA sites (INBDs), due to a succession of curvatures that cancel each other. In the present study, we mapped 11 INBDSs present in the AMPD2 gene that are related to each replication origin (oriGNAI3, oriC, oriB, and oriA). Following characterization of INBDSs, we tested the ability of HMGB1 to bind to the bent (b1, b2, b4a, b4b, b5, b6, b7, and b8) and non-bent DNA fragments (nb7, nb11, nb1, nb2, nb4, and nb5) via electrophoretic mobility shift assays. All fragments showed efficient binding to HMGB1. However, the non-bent DNA fragments nb2, nb4, and nb5 showed slightly reduced binding efficiency.

Genetic evaluation of AMPD1, CPT2, and PGYM metabolic enzymes in patients with chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) is a disease that can seriously impair one's quality of life; patients complain of excessive fatigue and myalgia following physical exertion. This disease may be associated with abnormalities in genes affecting exercise tolerance and physical performance. Adenosine monophosphate deaminase (AMPD1), carnitine palmitoyltransferase II (CPT2), and the muscle isoform of glycogen phosphorylase (PYGM) genes provide instructions for producing enzymes that play major roles in energy production during work. The aim of this study was to look for evidence of genotype-associated excessive muscle fatigue. Three metabolic genes (AMPD1, CPT2, and PYGM) were therefore fully sequenced in 17 Italian patients with CFS. We examined polymorphisms known to alter the function of these metabolic genes, and compared their genotypic distributions in CFS patients and 50 healthy controls using chi-square tests and odds ratios. One-way analysis of variance with F-ratio was carried out to determine the associations between genotypes and disease severity using CF scores. No major genetic variations between patients and controls were found in the three genes studied, and we did not find any association between these genes and CFS. In conclusion, variations in AMPD1, CPT2, and PGYM genes are not associated with the onset, susceptibility, or severity of CFS.

Association between the C34T polymorphism of the AMPD1 gene and essential hypertension in Malaysian patients.

The aim of this study was to determine whether C34T, a common polymorphism of the adenosine monophosphate deaminase 1 gene (AMPD1), is associated with essential hypertension (EH). We hypothesize that C34T is associated with the development of EH. A case-control design was used for this study. The DNA was extracted using a commercial kit from the whole blood of 200 patients with hypertension and 200 subjects without hypertension from selected Malaysian ethnicities (Malays, Chinese, and Indians). Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and agarose gel electrophoresis were used for genotyping. The C34T gene polymorphism of AMPD1 was significantly associated with EH in the Malaysian subjects (P < 0.0001). The genotype frequencies of CC, CT, and TT were 6%, 79%, and 15%, respectively, among hypertensive subjects, while no TT genotypes were observed in the normotensive subjects. Further, the frequency of hypertension was higher among T allele carriers than C carriers (OD = 9.94; 95%CI = 6.851-14.434). There were significant differences in the systolic blood pressure, diastolic blood pressure, and pulse pressure (P ˂ 0.05) between the normotensive and hypertensive Malaysian subjects; we believe those difference were caused by the C34T polymorphism. For the first time in Malaysia, the current study provides evidence that a common polymorphism of the AMPD1 gene (C34T) is strongly associated with EH.

Effects of the 34C>T Variant of the AMPD1 Gene on Immune Function, Multi-Organ Dysfunction, and Mortality in Sepsis Patients.

Adenosine exerts anti-inflammatory and tissue-protective effects during systemic inflammation. While the tissue-protective effects might limit organ damage, its anti-inflammatory properties may induce immunoparalysis and impede bacterial clearance. The common 34C>T loss-of-function variant of AMPD1 (rs17602729) is associated with increased adenosine formation, but effects on immune function and outcome in sepsis patients are unknown. The effects of the presence of the 34C>T variant on sepsis susceptibility, immune function, multi-organ dysfunction, and mortality in septic patients were studied. Patients suffering from community acquired pneumonia (CAP, initial cohort n = 285; replication cohort n = 212) and ventilator-associated pneumonia (VAP, n = 117; n = 33) and control patients without infection (n = 101) were enrolled. Genetic distributions of the AMPD1 SNP were CC 76%, CT 22%, and TT 2% in the initial cohort and CC 80%, CT 18%, and TT 2% in the replication cohort. The occurrence of septic CAP, but not septic VAP, was increased for the CT versus CC genotype (OR (95% CI) 2.0 (1.1-3.7); P = 0.02) in the initial cohort. The increased risk for the CT versus CC genotype was also observed in the replication cohort but did not reach statistical significance there (P = 0.38), resulting in an OR of the total group of 1.7 (95% CI 1.0-3.1), P = 0.07. In septic patients carrying the CT genotype, the ex vivo production of TNF-α by LPS-stimulated monocytes was attenuated (P = 0.005), indicative of a more pronounced immunoparalytic state in these patients. Presence of the AMPD1 34C>T variant is associated with higher infection susceptibility to CAP, but not to VAP. More pronounced immunoparalysis in these patients mediated by the anti-inflammatory effects of adenosine may account for this observation.

AMPD1: a novel therapeutic target for reversing insulin resistance.

BackgroundInsulin resistance is one of the hallmark manifestations of obesity and Type II diabetes and reversal of this pathogenic abnormality is an attractive target for new therapies for Type II diabetes. A recent report that metformin, a drug known to reverse insulin resistance, demonstrated in vitro the metformin can inhibit AMP deaminase (AMPD) activity. Skeletal muscle is one of the primary organs contributing to insulin resistance and that the AMPD1 gene is selectively expressed at high levels in skeletal muscle.MethodsRecognizing the background above, we asked if genetic disruption of the AMPD1 gene might ameliorate the manifestations of insulin resistance. AMPD1 deficient homozygous mice and control mice fed normal chow diet or a high-fat diet, and blood analysis, glucose tolerance test and insulin tolerance test were performed. Also, skeletal muscle metabolism and gene expression including nucleotide levels and activation of AMP activated protein kinase (AMP kinase) were evaluated in both conditions.ResultsDisruption of the AMPD1 gene leads to a less severe state of insulin resistance, improved glucose tolerance and enhanced insulin clearance in mice fed a high fat diet. Given the central role of AMP kinase in insulin action, and its response to changes in AMP concentrations in the cell, we examined the skeletal muscle of the AMPD1 deficient mice and found that they have greater AMP kinase activity as evidenced by higher levels of phosphorylated AMP kinase.ConclusionsTaken together these data suggest that AMPD may be a new drug target for the reversal of insulin resistance and the treatment of Type II diabetes.Electronic supplementary materialThe online version of this article (doi:10.1186/1472-6823-14-96) contains supplementary material, which is available to authorized users.