The Circassians and the Chechens in Jordan: results of a decade of epidemiological and genetic studies.

Circassians and Chechens in Jordan, both with Caucasian ancestry, are genetically isolated due to high rate of endogamous marriages. Recent interest in these populations has led to studies on their genetic similarities, differences, and epidemiological differences in various diseases. Research has explored their predisposition to conditions like diabetes, hypertension, and cancer. Moreover, pharmacogenetic (PGx) studies have also investigated medication response variations within these populations, and forensic studies have further contributed to understanding these populations. In this review article, we first discuss the background of these minority groups. We then show the results of a principle component analysis (PCA) to investigate the genetic relationships between Circassian and Chechen populations living in Jordan. We here present a summary of the findings from the 10 years of research conducted on them. The review article provides a comprehensive summary of research findings that are truly valuable for understanding the unique genetic characteristics, diseases' prevalence, and medication responses among Circassians and Chechens living in Jordan. We believe that gaining deeper comprehension of the root causes of various diseases and developing effective treatment methods that benefit the society as a whole are imperative to engaging a wide range of ethnic groups in genetic research.

Variability of CYP2C8 Polymorphisms in Three Jordanian Populations: Circassians, Chechens and Jordanian-Arabs.

CYP2C8 is a member of Cytochrome P450 enzymes system. It plays an important role in metabolizing a wide range of exogenous and endogenous compounds. CYP2C8 is involved in the metabolism of more than 100 drugs, typical substrates include: anticancer agents, antidiabetic agents, antimalarial agents, lipid lowering drugs and many others that constitute 20% of clinically prescribed drugs. Genetic variations of CYP2C8 have been reported with different frequencies in different populations. These genetic polymorphisms can lead to differences in the efficacy and safety of different types of medications metabolized by CYP2C8. The aim of this study was to investigate the allele frequencies of CYP2C8*3 (rs10509681 and rs11572080) and CYP2C8*4 (rs1058930) polymorphisms in three populations living in Jordan; Circassians and Chechens and Jordanian-Arabs and compare those frequencies with other populations. A total of 200 healthy Jordanians, 93 Circassians and 88 Chechens were included in this study. Genotyping of CYP2C8*3 and CYP2C8*4 polymorphisms was done by using polymerase chain reaction (PCR) followed by Restriction Fragment Length Polymorphism (RFLP). Using the Chi-square test, we found that the prevalence of CYP2C8*3 and *4 among the three populations were significantly different. Moreover, the mutant allele CYP2C8*3 (416A) was only detected in the Jordanian-Arab population with an allele frequency of 0.082, while the mutant allele CYP2C8*4 (792G) was detected with frequencies of 0.065, 0.122, 0.017 in Jordanian-Arabs, Circassians and Chechens, respectively. As our results show, CYP2C8*3 was undetectable in our Circassians and Chechens samples, on the other hand, Circassians had the highest allele frequency of CYP2C8*4 compared to Chechens and Jordanian-Arabs. These genetic variations of the gene encoding the CYP2C8 drug metabolizing enzymes can lead to clinical differences in drug metabolism and ultimately variations in drug effectiveness and toxicities. This study provides evidence for the importance of personalized medicine in these populations and can be the foundation for future clinical studies.

C-reactive protein, Epstein-Barr virus, and cortisol trajectories in refugee and non-refugee youth: Links with stress, mental health, and cognitive function during a randomized controlled trial.

Experiencing childhood adversity has been associated with significant changes in inflammation, cell-mediated immunocompetence, and cortisol secretion. Relatively few studies have examined, longitudinally, alterations to inflammatory processes during adolescence, especially outside Western contexts; none have evaluated biomarker trajectories for at-risk youth in response to a structured behavioral intervention. We conducted a randomized controlled trial evaluating the efficacy of a humanitarian intervention targeting stress-alleviation, with 12-18 year-old Syrian refugees (n = 446) and Jordanian non-refugees (n = 371) living side-by-side in war-affected communities in Jordan. We measured C-reactive protein (CRP), Epstein-Barr virus antibodies (EBV), and hair cortisol concentration (HCC) at three timepoints (pre/post intervention and 11 month follow-up), and assessed three main outcomes (psychosocial stress, mental health, and cognitive function). Using growth mixture models, regressions, and growth curve models, we identified three distinct trajectories for CRP, two for EBV, and three for HCC, and examined their associations with age, gender, BMI, poverty, and trauma. We found associations with BMI for CRP, refugee status for EBV, and BMI and gender with HCC trajectory. In terms of health outcomes, we found associations between rising CRP levels and perceived stress (B =  -2.92, p = .007), and between HCC hypersecretion and insecurity (B = 7.21, p = .017). In terms of responses to the intervention, we observed no differential impacts by CRP or EBV trajectories, unlike HCC. These results suggest that commonly-assayed biomarkers do not associate with health outcomes and respond to targeted interventions in straightforward ways. Our study is the first to examine multiple biomarker trajectories in war-affected adolescents, in order to better evaluate the extent, timing, and malleability of the biological signatures of poverty, conflict, and forced displacement.

Interethnic Variations of UGT1A1 and UGT1A7 Polymorphisms in the Jordanian Population.

BACKGROUND: Glucuronidation is one of the most important phase II metabolic pathways. It is catalyzed by a family of UDP-glucuronosyltransferase enzymes (UGTs). UGT1A1 and UGT1A7 catalyze the glucuronidation of a diverse range of medications, environmental chemicals and endogenous compounds. Polymorphisms in the UGT1A gene could potentially be significant for the pharmacological, toxicological and physiological effects of the enzymes. OBJECTIVE: The UGT1A gene is polymorphic among ethnic groups and the aim of this study was to investigate the different UGT1A1 and UGT1A7 polymorphisms in Circassians, Chechens and Jordanian-Arabs. METHODS: A total of 168 healthy Jordanian-Arabs, 56 Circassians and 54 Chechens were included in this study. Genotyping of 20 different Single-nucleotide polymorphism (SNPs) was done by using polymerase chain reaction- DNA sequencing. RESULTS: We found that Circassians and Chechens have significantly higher allele frequencies of UGT1A7*2, UGT1A7*3 and UGT1A7*4 than the Jordanian-Arab population, but all three populations have similar frequencies of UGT1A1*28. Therefore, Circassians and Chechens are expected to have significantly lower levels of the UGT1A7 enzyme with almost 90% of these populations having genes that encode low or intermediate enzyme activity. CONCLUSION: This inter-ethnic variation in the UGT1A alleles frequencies may affect drug response and susceptibility to cancers among different subethnic groups in Jordan. Our results can also provide useful information for the Jordanian population and for future genotyping of Circassian and Chechen populations in general.

Structural cycle of the Thermus thermophilus PilF ATPase: the powering of type IVa pilus assembly.

Type IV pili are responsible for a diverse range of functions, including twitching motility and cell adhesion. Assembly of the pilus fiber is driven by a cytoplasmic ATPase: it interacts with an inner membrane complex of biogenesis proteins which, in turn, bind to nascent pilin subunits and mediate fiber assembly. Here we report the structural characterization of the PilF TFP assembly ATPase from Thermus thermophilus. The crystal structure of a recombinant C-terminal fragment of PilF revealed bound, unhydrolysed ATP, although the full length complex was enzymatically active. 3D reconstructions were carried out by single particle cryoelectron microscopy for full length apoprotein PilF and in complex with AMPPNP. The structure forms an hourglass-like shape, with the ATPase domains in one half and the N1 domains in the second half which, we propose, interact with the other pilus biogenesis components. Molecular models for both forms were generated: binding of AMPPNP causes an upward shift of the N1 domains towards the ATPase domains of ~8 Å. We advocate a model in which ATP hydrolysis is linked to displacement of the N1 domains which is associated with lifting pilin subunits out of the inner membrane, and provide the activation energy needed to form the pilus fiber.

Insecurity, distress and mental health: experimental and randomized controlled trials of a psychosocial intervention for youth affected by the Syrian crisis.

BACKGROUND: Strengthening the evidence base for humanitarian interventions that provide psychosocial support to war-affected youth is a key priority. We tested the impacts of an 8-week programme of structured activities informed by a profound stress attunement (PSA) framework (Advancing Adolescents), delivered in group-format to 12-18 year-olds in communities heavily affected by the Syrian crisis. We included both Syrian refugee and Jordanian youth. METHODS: We followed an experimental design, comparing treatment youth and wait-list controls over two programme implementation cycles, randomizing to study arm in cycle 2 (ClinicalTrials.gov ID: NCT03012451). We measured insecurity, distress, mental health difficulties, prosocial behaviour and post-traumatic stress symptoms at three time-points: baseline (n = 817 youth; 55% Syrian, 43% female), postintervention (n = 463; 54% Syrian, 47% female), and follow-up (n = 212, 58% Syrian, 43% female). Regression models assessed: prospective intervention impacts, adjusting for baseline scores, trauma exposure, age, and gender; differential impacts across levels of trauma exposure and activity-based modality; and sustained recovery 1 year later. We analysed cycle-specific and cycle-pooled data for youth exclusively engaged in Advancing Adolescents and for the intent-to-treat sample. RESULTS: We found medium to small effect sizes for all psychosocial outcomes, namely Human Insecurity (ß = -7.04 (95% CI: -10.90, -3.17), Cohen's d = -0.4), Human Distress (ß = -5.78 (-9.02, -2.54), d = -0.3), and Perceived Stress (ß = -1.92 (-3.05, -0.79), d = -0.3); and two secondary mental health outcomes (AYMH: ß = -3.35 (-4.68, -2.02), d = -0.4; SDQ: ß = -1.46 (-2.42, -0.50), d = -0.2). We found no programme impacts for prosocial behaviour or post-traumatic stress reactions. Beneficial impacts were stronger for youth with exposure to four trauma events or more. While symptoms alleviated for both intervention and control groups over time, there were sustained effects of the intervention on Human Insecurity. CONCLUSIONS: Findings strengthen the evidence base for mental health and psychosocial programming for a generation affected by conflict and forced displacement. We discuss implications for programme implementation and evaluation research.

Cord Blood Banking in the Arab World: Current Status and Future Developments.

Umbilical cord blood transplants are now used to treat numerous types of immune- and blood-related disorders and genetic diseases. Cord blood (CB) banks play an important role in these transplants by processing and storing CB units. In addition to their therapeutic potential, these banks raise ethical and regulatory questions, especially in emerging markets in the Arab world. In this article, the authors review CB banking in five countries in the region, Jordan, Saudi Arabia, Egypt, Qatar, and the United Arab Emirates, selected for their different CB banking policies and initiatives. In assessing these case studies, the authors present regional trends and issues, including religious perspectives, policies, and demographic risk factors. This research suggests strong incentives for increasing the number of CB units that are collected from and available to Arab populations. In addition, the deficit in knowledge concerning public opinion and awareness in the region should be addressed to ensure educated decision-making.

Nutrient intake and lifestyle factors by diabetes status of Circassians and Chechans in Jordan.

OBJECTIVES: Diabetes is one of the most prevalent diseases in Jordan. However, little is known about nutrient intakes of minority groups in Jordan with and without diabetes. Our study aimed to examine if the intake of energy, macronutrients and some micronutrients differed between normal and diabetic adults among Circassians and Chechans in Jordan. DESIGN, SETTING, PARTICIPANTS: This cross-sectional study was conducted among 437 Circassians (160 males and 277 females) and 355 Chechans (119 males and 236 females) aged > or = 18 years. They were recruited from the Chechan and Circassian communities living in Jordan. MAIN OUTCOME MEASURES: A participant was defined as affected by type 2 diabetes mellitus if diagnosis was known to patient or if his or her condition complied with the American Diabetes Association definition. One 24-hour dietary recall for each participant was collected by face-to-face interview. RESULTS: Most of the measured anthropometric and biochemical parameters showed a significant difference between normal individuals and those with impaired fasting glucose or diabetes. Intakes of nutrients involved in the pathogenesis of diabetes including protein, fat and fiber did not differ between stratified participants according to blood glucose status for both Circassians and Chechans. CONCLUSIONS: Intake of nutrients did not differ in participants with normal blood glucose from those who had impaired fasting glucose or diabetes in the two studied populations. These two populations may need genetic studies to identify the risk factors other than dietary and lifestyle factors for type 2 diabetes.

Comparison of population based cancer incidence rates among Circassians, Chechans and Arabs in Jordan (1996-2005).

BACKGROUND: Cancer is a complex disease caused by multiple factors, both genetic and environmental. It is a major health concern worldwide, in the Middle East and in Jordan specifically and the fourth most common killer in the Middle East. HYPOTHESIS: The relative genetic homogeneity of the Circassian and Chechan populations in Jordan results in incidences of cancer that differ from the general Jordanian population, who are mostly Arabs. MATERIALS AND METHODS: National Cancer Registry data were obtained for the years 1996-2005 The Chechen and Circassian cancer cases were identified and cancer registry data were divided into three populations. Crude rates were calculated based on the number of cancer cases and estimated populations. RESULTS: Breast cancer is the most common cancer type constituting about one third of female cancers in all three populations. Higher crude rates are observed in the Circassian and Chechen populations than in the Arab Jordanian population. The rate ratios (95%CI) in Circassians and Chechens with respect to the Arab Jordanian population are 2.1 (1.48, 2.72) and 1.81 (1.16, 2.85), respectively. Lung cancer is the most common cancer in male Arab Jordanians and Chechens with crude rates of 4.2 and 8.0 per 100,000 respectively. The male to female ratio in these two populations in respective order are 5:1 and 7:1. The lung cancer crude rate in Circassians is 6.5 per 100,000 with a male to female ratio of only 1.6:1. The colorectal cancer crude rates in Arab Jordanians and Chechens are similar at 6.2 and 6.0 per 100,000, respectively, while that in Circassians is twice as high. CONCLUSIONS: Considerable ethnic variation exists for cancer incidence rates in Jordan. The included inbred and selected populations offer an ideal situation for investigating genetic factors involved in various cancer types.

Macrophage colony stimulating factor and monocyte chemoattractant protein 2 are elevated in intrinsic asthmatics.

BACKGROUND: Intrinsic asthma, etiology unknown, occurs later in life, mostly in females. It is associated with nasal polyps and massive eosinopillic infiltration of the respiratory mucous membrane, aspirin intolerance and steroid dependence. The aim of the study was to determine the cytokine and chemokine profile in sera of intrinsic asthmatics and control subjects. METHODS: Blood was taken from 10 intrinsic asthmatic female and 12 control female subjects. Expression profile of 42 different cytokines and chemokines were measured using a microarray composed of antibodies against the cytokines and chemokines. Complete blood count and C-reactive protein were measured, to assess the state of inflammation in both groups. RESULTS: We have identified Macrophage Colony Stimulating Factor, a proinflammatory cytokine and Monocyte Chemoattractant Protein 2, a CC chemokine as having significantly higher expression levels in intrinsic asthmatic subjects compared to controls (341.71±31.28 SEM Signal intensity) versus (247.97±28.09 SEM Signal intensity), p=0.036 and (397.07±38.19 SEM Signal intensity) versus (311.33±28.76 SEM Signal intensity), p=0.036, respectively. There were no significant differences in the other cytokines and chemokines measured nor were there any differences in the inflammatory measurements between the two groups except for eosinophil counts, the hall mark of intrinsic asthma. CONCLUSION: Macrophage Colony Stimulating Factor and Monocyte Chemoattractant Protein are elevated in sera of intrinsic asthmatics compared to normal controls. These cytokines may have a critical role in the inflammatory pathology of intrinsic asthma.

Pleiotropic functions of TNF-alpha determine distinct IKKbeta-dependent hepatocellular fates in response to LPS.

TNF-alpha influences morbidity and mortality during the course of endotoxemia. However, the complex pleiotropic functions of TNF-alpha remain poorly understood. We evaluated how hepatic induction of NF-kappaB and TNF-alpha influence survival and hepatocellular death in a lethal murine model of endotoxic shock. Using dominant-negative viral vectors to inhibit the IKK complex, we demonstrate through this study that the liver is a major source of TNF-alpha during the course of lethal endotoxemia and that IKKbeta (but not IKKalpha) is predominantly responsible for activating NF-kappaB and TNF-alpha in the liver after LPS administration. Using TNF-alpha knockout mice and hepatic-specific inhibition of IKKbeta, we demonstrate that the status of TNF-alpha and NF-kappaB balances necrotic and apoptotic fates of hepatocytes in the setting of endotoxemia. In the presence of TNF-alpha, inhibiting hepatic IKKbeta resulted in increased survival, reduced serum proinflammatory cytokines, and reduced hepatocyte necrosis in response to a lethal dose of endotoxin. In contrast, inhibiting hepatic IKKbeta in TNF-alpha knockout mice resulted in decreased survival and increased caspase 3-mediated hepatocyte apoptosis after endotoxin challenge, despite a reduced proinflammatory cytokine response. In the presence of TNF-alpha, NF-kappaB-dependent hepatocellular necrosis predominated, while in the absence of TNF-alpha, NF-kappaB primarily influenced apoptotic fate of hepatocytes. Changes in JNK phosphorylation after LPS challenge were also dynamically affected by both IKKbeta and TNF-alpha; however, this pathway could not solely explain the differential outcomes in hepatocellular fates. In conclusion, our studies demonstrate that induction of NF-kappaB and TNF-alpha balances protective (antiapoptotic) and detrimental (proinflammatory) pathways to determine hepatocellular fates during endotoxemia.

Lysozyme secretion by submucosal glands protects the airway from bacterial infection.

Submucosal glands are abundant (approximately 1 gland/mm2) secretory structures in the tracheobronchial airways of the human lung. Because submucosal glands express antibacterial proteins, it has been proposed that they contribute to lung defense. However, this concept is challenged by the fact that mice do not have submucosal glands in their bronchial airways, yet are quite resistant to bacterial lung infection. The contribution of airway submucosal glands to host defense is also debated as a pathophysiologic component of cystic fibrosis lung disease. Here, we asked whether submucosal glands protect airways against bacterial infection. By comparing tracheal xenograft airways with and without glands, we found that the presence of glands enhanced bacterial killing in vivo and by airway secretions in vitro. Moreover, immunodepletion studies suggested that lysozyme is a major antibacterial component secreted by submucosal glands. These studies provide evidence that submucosal glands are a major source of antibacterials critical for maintaining sterile airways.

Structural basis for recruitment of glycogen synthase kinase 3beta to the axin-APC scaffold complex.

Glycogen synthase kinase 3beta (GSK3beta) is a serine/threonine kinase involved in insulin, growth factor and Wnt signalling. In Wnt signalling, GSK3beta is recruited to a multiprotein complex via interaction with axin, where it hyperphosphorylates beta-catenin, marking it for ubiquitylation and destruction. We have now determined the crystal structure of GSK3beta in complex with a minimal GSK3beta-binding segment of axin, at 2.4 A resolution. The structure confirms the co-localization of the binding sites for axin and FRAT in the C-terminal domain of GSK3beta, but reveals significant differences in the interactions made by axin and FRAT, mediated by conformational plasticity of the 285-299 loop in GSK3beta. Detailed comparison of the axin and FRAT GSK3beta complexes allows the generation of highly specific mutations, which abrogate binding of one or the other. Quantitative analysis suggests that the interaction of GSK3beta with the axin scaffold enhances phosphorylation of beta-catenin by >20 000-fold.

GSK-3-selective inhibitors derived from Tyrian purple indirubins.

Gastropod mollusks have been used for over 2500 years to produce the "Tyrian purple" dye made famous by the Phoenicians. This dye is constituted of mixed bromine-substituted indigo and indirubin isomers. Among these, the new natural product 6-bromoindirubin and its synthetic, cell-permeable derivative, 6-bromoindirubin-3'-oxime (BIO), display remarkable selective inhibition of glycogen synthase kinase-3 (GSK-3). Cocrystal structure of GSK-3beta/BIO and CDK5/p25/indirubin-3'-oxime were resolved, providing a detailed view of indirubins' interactions within the ATP binding pocket of these kinases. BIO but not 1-methyl-BIO, its kinase inactive analog, also inhibited the phosphorylation on Tyr276/216, a GSK-3alpha/beta activation site. BIO but not 1-methyl-BIO reduced beta-catenin phosphorylation on a GSK-3-specific site in cellular models. BIO but not 1-methyl-BIO closely mimicked Wnt signaling in Xenopus embryos. 6-bromoindirubins thus provide a new scaffold for the development of selective and potent pharmacological inhibitors of GSK-3.

Glycogen synthase kinase-3 inhibition by lithium and beryllium suggests the presence of two magnesium binding sites.

Lithium inhibits (Li(+)) glycogen synthase kinase-3 (GSK-3) by competition for magnesium (Mg(2+)), but not ATP or substrate. Here, we show that the group II metal ion beryllium (Be(2+)) is a potent inhibitor of GSK-3 and competes for both Mg(2+) and ATP. Be(2+) also inhibits the related protein kinase cdc2 at similar potency, but not MAP kinase 2. To compare the actions of Li(+) and Be(2+) on GSK-3, we have devised a novel dual inhibition analysis. When Be(2+) and ADP are present together each interferes with the action of the other, indicating that both agents inhibit GSK-3 at the ATP binding site. In contrast, Li(+) exerts no interference with ADP inhibition or vice versa. We find, however, that Li(+) and Be(2+) do interfere with each other. These results suggest that Be(2+) competes for two distinct Mg(2+) binding sites: one is Li(+)-sensitive and the other, which is Li(+)-insensitive, binds the Mg:ATP complex.

Identification of the Axin and Frat binding region of glycogen synthase kinase-3.

Glycogen synthase kinase-3 (GSK-3) is a key component of several signaling pathways including those regulated by Wnt and insulin ligands. Specificity in GSK-3 signaling is thought to involve interactions with scaffold proteins that localize GSK-3 regulators and substrates. This report shows that GSK-3 forms a low affinity homodimer that is disrupted by binding to Axin and Frat. Based on the crystal structure of GSK-3, we have used surface-scanning mutagenesis to identify residues that differentially affect GSK-3 interactions. Mutations that disrupt Frat and Axin cluster at the dimer interface explaining their effect on homodimer formation. Loss of the Axin binding site blocks the ability of dominant negative GSK-3 to cause axis duplication in Xenopus embryos. The Axin binding site is conserved within all GSK-3 proteins, and its loss affects both cell motility and gene expression in the nonmetazoan, Dictyostelium. Surprisingly, we find no genetic interaction between a non-Axin-binding GSK-3 mutant and T-cell factor activity, arguing that Axin interactions alone cannot explain the regulation of T-cell factor-mediated gene expression.