Vitamin D insufficiency in Arabs and South Asians positively associates with polymorphisms in GC and CYP2R1 genes

Background

A number of genetic studies have reported an association between vitamin D related genes such as group-specific component gene (GC), Cytochrome P450, family 2, subfamily R, polypeptide 1 (CYP2R1) and 7-dehydrocholesterol reductase/nicotinamide-adenine dinucleotide synthetase 1 (DHCR7/NADSYN1) and serum levels of the active form of Vitamin D, 25 (OH) D among African Americans, Caucasians, and Chinese. Little is known about how genetic variations associate with, or contribute to, 25(OH)D levels in Arabs populations.

Methods

Allele frequencies of 18 SNPs derived from CYP2R1, GC, and DHCR7/NADSYN1 genes in 1549 individuals (Arabs, South Asians, and Southeast Asians living in Kuwait) were determined using real time genotyping assays. Serum levels of 25(OH)D were measured using chemiluminescence immunoassay.

Results

GC gene polymorphisms (rs17467825, rs3755967, rs2282679, rs7041 and rs2298850) were found to be associated with 25(OH)D serum levels in Arabs and South Asians. Two of the CYP2R1 SNPs (rs10500804 and rs12794714) and one of GC SNPs (rs1155563) were found to be significantly associated with 25(OH)D serum levels only in people of Arab origin. Across all three ethnicities none of the SNPs of DHCR7/NADSYN1 were associated with serum 25(OH)D levels and none of the 18 SNPs were significantly associated with serum 25(OH)D levels in people from South East Asia.

Conclusion

Our data show for the first time significant association between the GC (rs2282679 and rs7041), CYP2R1 (rs10741657) SNPs and 25(OH)D levels. This supports their roles in vitamin D Insufficiency in Arab and South Asian populations respectively. Interestingly, two of the CYP2R1 SNPs (rs10500804 and rs12794714) and one GC SNP (rs1155563) were found to correlate with vitamin D in Arab population exclusively signifying their importance in this population.

FSL-1 induces MMP-9 production through TLR-2 and NF-κB /AP-1 signaling pathways in monocytic THP-1 cells

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is known to be implicated in the pathogenesis of many inflammatory disorders. FSL-1 (fibroblast-stimulating lipopeptide-1) induces cytokine production by monocytes/macrophages. However, it is unclear whether FSL-1 is also able to induce MMP-9 production. Herein, we determined whether FSL-1 could induce MMP-9 production, and if so, which signal transduction pathway(s) were involved.

METHODS

MMP-9 expression was assessed with real-time qPCR and ELISA. Signaling pathways were studied by using THP1-XBlue™ cells, THP1-XBlue™-defMyD cells, anti-TLR2 mAb and pharmacological inhibitors. Phospho and total proteins were determined by Western blotting.

RESULTS

FSL-1 induces MMP-9 expression (P<0.001) at both mRNA and protein levels in human monocytic THP-1 cells. Elevated activity (P<0.001) of NF-κB/AP-1 was also observed in FSL-1-treated THP-1 cells. FSL-1-induced MMP-9 secretion was markedly suppressed either by neutralizing anti-TLR-2 antibody or by inhibiting clathrin-dependent endocytosis. Furthermore, MyD88(-/-) THP-1 cells did not express MMP-9 in response to FSL-1 treatment. By small interfering RNA-mediated knockdown, we also show that FSL-1-induced up-regulation of MMP-9 requires MyD88. Pre-treatment of THP-1 cells with inhibitors of JNK (SP600125), MEK/ERK (U0126; PD98056; XMD 8-92), p38 MAPK (SB203580) and NF-κB (BAY11-7085, Triptolide, Resveratrol) significantly suppressed (P<0.05) MMP-9 gene expression and NF-κB/AP-1 transcription factors activity.

CONCLUSION

These findings provide the first evidence that FSL-1 induces TLR-2-dependent MMP-9 gene expression which requires the recruitment of MyD88 and leads to activation of MEK1/2 /ERK 1/2, MEK5/ERK5, JNK, p38 MAPK and NF-κB/AP-1.

Leptin in association with common variants of MC3R mediates hypertension

BACKGROUND

Recent research illustrates the role of central melanocortin signaling and leptin in the regulation of arterial blood pressure in animal models. Unraveling the genetic basis of interactions between melanocortin and leptin in humans will provide new insight into the regulation of arterial pressure.

METHOD

Our study population consisted of 332 Kuwaiti natives. Polymorphisms from exons of leptin, MC3R, and MC4R genes were identified by Sanger sequencing. MC3R expression and leptin levels were determined. Linear regression models, adjusted for age, gender, antihypertensive medication, and body mass index, were used to perform statistical association tests.

RESULTS

We observed a significant association between the MC3R missense variant (rs3827103 [Val81 Ile]) and systolic blood pressure (SBP; P = 0.01, β = 4.9). The N-terminus variant (rs3746619 [Thr6→Lys]) is in linkage disequilibrium (r2 = 0.65) with the rs3827103 variant. The AA haplotype of rs3746619-rs3827103 is significantly associated with SBP (P = 0.005, β=5.03). Minor allele frequencies of these two variants in the Kuwaiti population are twice those seen in European population. In individuals who harbor these variants, we found that the plasma leptin levels were positively correlated with SBP and that the expression of MC3R was downregulated. Leptin levels correlated with obesity traits irrespective of the genotypes at the variant positions.

CONCLUSION

An increase in leptin levels is known to increase sympathetic nerve activity that, in turn, increases blood pressure. Thus, it is possible that the observed MC3R variants in association with leptin levels are involved in regulation of blood pressure in humans.

Immunohistochemical profiling of the heat shock response in obese non-diabetic subjects revealed impaired expression of heat shock proteins in the adipose tissue

BACKGROUND

Obesity is characterized by a chronic low-grade inflammation and altered stress responses in key metabolic tissues. Impairment of heat shock response (HSR) has been already linked to diabetes and insulin resistance as reflected by decrease in heat shock proteins (HSPs) expression. However, the status of HSR in non-diabetic human obese has not yet been elucidated. The aim of the current study was to investigate whether obesity triggers a change in the HSR pattern and the impact of physical exercise on this pattern at protein and mRNA levels.

METHODS

Two groups of adult non-diabetic human subjects consisting of lean and obese (n = 47 for each group) were enrolled in this study. The expression pattern of HSP-27, DNAJB3/HSP-40, HSP-60, HSC-70, HSP72, HSP-90 and GRP-94 in the adipose tissue was primarily investigated by immunohistochemistry and then complemented by western blot and qRT-PCR in Peripheral blood mononuclear cells (PBMCs). HSPs expression levels were correlated with various physical, clinical and biochemical parameters. We have also explored the effect of a 3-month moderate physical exercise on the HSPs expression pattern in obese subjects.

RESULTS

Obese subjects displayed increased expression of HSP-60, HSC-70, HSP-72, HSP-90 and GRP-94 and lower expression of DNAJB3/HSP-40 (P < 0.05). No differential expression was observed for HSP-27 between the two groups. Higher levels of HSP-72 and GRP-94 proteins correlated positively with the indices of obesity (body mass index and percent body fat) and circulating levels of IFN-gamma-inducible protein 10 (IP-10) and RANTES chemokines. This expression pattern was concomitant with increased inflammatory response in the adipose tissue as monitored by increased levels of Interleukin-6 (IL-6), Tumor necrosis factor-α (TNF-α), and RANTES (P < 0.05). Physical exercise reduced the expression of various HSPs in obese to normal levels observed in lean subjects with a parallel decrease in the endogenous levels of IL-6, TNF-α, and RANTES.

CONCLUSION

Taken together, these data indicate that obesity triggers differential regulation of various components of the HSR in non-diabetic subjects and a 3-month physical moderate exercise was sufficient to restore the normal expression of HSPs in the adipose tissue with concomitant attenuation in the inflammatory response.

Metabolic disease risk in children by salivary biomarker analysis

Objective

The study of obesity-related metabolic syndrome or Type 2 diabetes (T2D) in children is particularly difficult because of fear of needles. We tested a non-invasive approach to study inflammatory parameters in an at-risk population of children to provide proof-of-principle for future investigations of vulnerable subjects.

Design and Methods

We evaluated metabolic differences in 744, 11-year old children selected from underweight, normal healthy weight, overweight and obese categories by analyzing fasting saliva samples for 20 biomarkers. Saliva supernatants were obtained following centrifugation and used for analyses.

Results

Salivary C-reactive protein (CRP) was 6 times higher, salivary insulin and leptin were 3 times higher, and adiponectin was 30% lower in obese children compared to healthy normal weight children (all P<0.0001). Categorical analysis suggested that there might be three types of obesity in children. Distinctly inflammatory characteristics appeared in 76% of obese children while in 13%, salivary insulin was high but not associated with inflammatory mediators. The remaining 11% of obese children had high insulin and reduced adiponectin. Forty percent of the non-obese children were found in groups which, based on biomarker characteristics, may be at risk for becoming obese.

Conclusions

Significantly altered levels of salivary biomarkers in obese children from a high-risk population, suggest the potential for developing non-invasive screening procedures to identify T2D-vulnerable individuals and a means to test preventative strategies.

Genome at juncture of early human migration: a systematic analysis of two whole genomes and thirteen exomes from Kuwaiti population subgroup of inferred Saudi Arabian tribe ancestry

Population of the State of Kuwait is composed of three genetic subgroups of inferred Persian, Saudi Arabian tribe and Bedouin ancestry. The Saudi Arabian tribe subgroup traces its origin to the Najd region of Saudi Arabia. By sequencing two whole genomes and thirteen exomes from this subgroup at high coverage (>40X), we identify 4,950,724 Single Nucleotide Polymorphisms (SNPs), 515,802 indels and 39,762 structural variations. Of the identified variants, 10,098 (8.3%) exomic SNPs, 139,923 (2.9%) non-exomic SNPs, 5,256 (54.3%) exomic indels, and 374,959 (74.08%) non-exomic indels are 'novel'. Up to 8,070 (79.9%) of the reported novel biallelic exomic SNPs are seen in low frequency (minor allele frequency <5%). We observe 5,462 known and 1,004 novel potentially deleterious nonsynonymous SNPs. Allele frequencies of common SNPs from the 15 exomes is significantly correlated with those from genotype data of a larger cohort of 48 individuals (Pearson correlation coefficient, 0.91; p <2.2×10-16). A set of 2,485 SNPs show significantly different allele frequencies when compared to populations from other continents. Two notable variants having risk alleles in high frequencies in this subgroup are: a nonsynonymous deleterious SNP (rs2108622 [19:g.15990431C>T] from CYP4F2 gene [MIM:*604426]) associated with warfarin dosage levels [MIM:#122700] required to elicit normal anticoagulant response; and a 3' UTR SNP (rs6151429 [22:g.51063477T>C]) from ARSA gene [MIM:*607574]) associated with Metachromatic Leukodystrophy [MIM:#250100]. Hemoglobin Riyadh variant (identified for the first time in a Saudi Arabian woman) is observed in the exome data. The mitochondrial haplogroup profiles of the 15 individuals are consistent with the haplogroup diversity seen in Saudi Arabian natives, who are believed to have received substantial gene flow from Africa and eastern provenance. We present the first genome resource imperative for designing future genetic studies in Saudi Arabian tribe subgroup. The full-length genome sequences and the identified variants are available at ftp://dgr.dasmaninstitute.org and http://dgr.dasmaninstitute.org/DGR/gb.html.

IL-33 is negatively associated with the BMI and confers a protective lipid/metabolic profile in non-diabetic but not diabetic subjects

Objective

Recent studies have demonstrated a protective role for IL-33 against obesity-associated inflammation, atherosclerosis and metabolic abnormalities. IL-33 promotes the production of T helper type 2 (Th2) cytokines, polarizes macrophages towards a protective alternatively activated phenotype, reduces lipid storage and decreases the expression of genes associated with lipid metabolism and adipogenesis. Our objective was to determine the level of serum IL-33 in non-diabetic and diabetic subjects, and to correlate these levels with clinical (BMI and body weight) and metabolic (serum lipids and HbA1c) parameters.

Methods

The level of IL-33 was measured in the serum of lean, overweight and obese non-diabetic and diabetic subjects, and then correlated with clinical and metabolic parameters.

Results

Non-lean subjects had significantly (P = 0.01) lower levels of IL-33 compared to lean controls. IL-33 was negatively correlated with the BMI and body weight in lean and overweight, but not obese (non-diabetic and diabetic), subjects. IL-33 is associated with protective lipid profiles, and is negatively correlated with HbA1c, in non-diabetic (lean, overweight and obese) but not diabetic subjects.

Conclusions

Our data support previous findings showing a protective role for IL-33 against adiposity and atherosclerosis, and further suggest that reduced levels of IL-33 may put certain individuals at increased risk of developing atherosclerosis and insulin resistance. Therefore, IL-33 may serve as a novel marker to predict those who may be at increased risk of developing atherosclerosis.

Cardiovascular disease risk factors in the South Asian population living in Kuwait: a cross-sectional study

BACKGROUND

High rates of diabetes and cardiovascular disease have been reported in South Asian immigrants in many countries. However, the prevalence and characteristics of cardiovascular disease risk factors among a South Asian population living in Kuwait have not yet been investigated. This study was therefore designed to estimate the prevalence of cardiovascular disease risk factors and determine whether they are independently associated with diabetes in such a population.

METHODS

A population-based cross-sectional study was conducted on 1094 South Asians (781 men and 313 women), mainly Indian and Pakistani (≥ 18 years of age), of whom 75.1% were Indians. Interviews were carried out, during which socio-demographic and anthropometric data were collected, followed by a physical examination and collection of fasting blood samples for laboratory investigations. Diabetes was defined by fasting plasma glucose ≥ 7 mmol/l, or being on treatment, and/or self-reported previously diagnosed Type 2 diabetes.

RESULTS

The prevalence of diabetes was 21.1%, with 3.4% of that percentage of people being newly diagnosed. Using BMI measurements, 24.0% of those who participated in the study were obese and 46.1% were overweight. Dyslipidaemia was found in 77.6% and hypertension in 44.8%. Advancing age (≥ 40 years), male gender, high LDL, high total cholesterol, hypertension and positive family history of diabetes were significantly associated with increased risk of diabetes.

CONCLUSION

Our study shows that the prevalence of cardiovascular disease risk factors in South Asian expatriates in Kuwait exceeds prevalence rates reported in their homeland and other countries. This may suggest the added stress of environmental factors on the development of cardiovascular disease risk factors in such populations. Specialized prevention programmes targeting such high-risk ethnic populations are paramount and need to be implemented.

Impact of hypertension on the association of BMI with risk and age at onset of type 2 diabetes mellitus: age- and gender-mediated modifications

AIMS

Given that BMI correlates with risk of Type 2 diabetes mellitus (T2DM), and that hypertension is a common comorbid condition, we hypothesize that hypertension augments significantly the impact of obesity on T2DM onset.

METHODS

We obtained data on T2DM in Kuwaiti natives from Kuwait Health Network Registry. We considered 1339 comorbid individuals with onset of hypertension preceding that of T2DM, and 3496 non-hypertensive individuals but with T2DM. Multiple linear regressions, ANOVA tests, and Cox proportional hazards models were used to quantify the impact of hypertension on correlation of BMI with age at onset and risk of T2DM.

RESULTS

Impact of increasing levels of BMI on age at onset ot T2DM is seen augmented in patients diagnosed with hypertension. We find that the slope of the inverse linear relationship between BMI and onset age of T2DM is much steep in hypertensive patients (-0.69, males and -0.39, females) than in non-hypertensive patients (-0.36, males and -0.17, females). The decline in onset age for an unit increase of BMI is two-fold in males than in females. Upon considering BMI as a categorical variable, we find that while the mean onset age of T2DM in hypertensive patients decreases by as much as 5-12 years in every higher BMI categories, significant decrease in non-hypertensive patients exists only when severely obese. Hazard due to hypertension (against the baseline of non-hypertension and normal weight) increases at least two-fold in every obese category. While males have higher hazard due to hypertension in early adulthood, females have higher hazard in late adulthood.

CONCLUSION

Pre-existing condition of hypertension augments the association of BMI with Type 2 diabetes onset in both males and females. The presented results provide health professionals directives on the extent of weight-loss required to delay onset of Type 2 diabetes in hypertensive versus non-hypertensive patients.

Comprehensive analysis of circulating adipokines and hsCRP association with cardiovascular disease risk factors and metabolic syndrome in Arabs

Background

Cardiovascular diseases (CVD) are a leading cause of death worldwide including the Middle East. This is caused in part by the dysregulation of adipose tissue leading to increased production of pro-inflammatory adipokines and reduction in cardio-protective adipokines such as adiponectin. Ethnicity has been recognized as a major factor in the association between CVD risk factors and the different circulating adipokines. In this study, for the first time, the relationship between traditional cardiovascular risk factors, Metabolic Syndrome (MetS) and circulating level of adipokines in Arab ethnicity was investigated.

Methods

We conducted a population-based cross-sectional survey on 379 adult Arab participants living in Kuwait. Traditional cardiovascular risk factors such as blood pressure (BP), low density lipoprotein (LDL) and triglyceride (TG) were measured. Plasma levels of circulating Leptin, Plasminogen Activator Inhibitor (PAI-1) visfatin, adiponectin, resistin and adipsin were assessed using the multiplexing immunobead-based assay.

Results

Circulating levels of High sensitivity C-Reactive Protein (hsCRP), Leptin, PAI-1 and adiponectin were significantly higher in Arab women than men (p < 0.0001). In multi-variate analysis, the homeostasis model assessment-insulin resistance (HOMA-IR) and body mass index (BMI) showed strong association with most of the biomarkers (p < 0.05). HsCRP showed significant association with all risk factors (p < 0.05). Leptin, PAI-1 and adipsin showed significant positive correlation with BMI, unlike adiponectin which showed inverse correlation (p < 0.05). Subjects in the highest tertile of leptin, PAI-1 and hsCRP had higher odds of having Metabolic Syndrome (MetS) (odd ratio [OR] = 3.02, 95% confidence interval [CI] = 1.47 – 6.19) and (OR = 2.52, 95% CI = 1.45 – 4.35), (OR = 4.26, 95% CI = 2.39 – 7.59) respectively. On the other hand subjects with highest tertile of adiponectin had lower odds of having MetS (OR = 0.22, 95% CI = 0.12 – 0.40). Leptin, PAI-1 and hsCRP showed significant positive association with increased MetS components (P-trend <0.05), while adiponectin was negatively associated with increased MetS components (P-trend <0.0001).

Conclusion

Our results show positive association between hsCRP, leptin, PAI-1 with increased MetS components and increase the odds of having MetS. Adiponectin on the other hand showed inverse correlation with MetS components and associated with reduction in MetS. Overall, our data highlights the significant clinical value these markers have in MetS especially hsCRP which can be used as good marker of low grade inflammation in Arabs.

ND4L gene concurrent 10609T>C and 10663T>C mutations are associated with Leber's hereditary optic neuropathy in a large pedigree from Kuwait

Background

Leber's hereditary optic neuropathy (LHON) is a condition characterised by a rapid bilateral central vision loss due to death of the retinal ganglion cells, leading to visual impairment commonly occurring during young adulthood. The disease manifests itself more in male patients than female patients. The mtDNA mutations m.11778G>A, m.3460G>A and m.14484T>C are by far more frequent in LHON than any other mutation. In this report, a multi-generational Arab family from Kuwait with 14 male members with LHON was investigated.

Methods

Complete mtDNA mutational analysis by direct Sanger's sequencing was carried out to detect pathogenic mutations, polymorphisms and haplogrouping.

Results

All maternally related subjects from this study who were examined expressed the L3 haplotype background, with two concurrent mtDNA mutations, 10609T>C and 10663T>C, that led to non-conservative amino acid changes of Ile47Thr and Val65Ala, respectively. The two variations were absent in 144 normal and ethnicity-matched controls.

Conclusions

The two identified mutations associated with LHON in this family may exert their pathogenicity through a cumulative or haplogroup effect. This is the first report of the presence of two concurrent mutations in the ND4L gene in individuals with LHON who carry the L3 haplogroup.

Taking the learning beyond the individual: how reflection informs change in practice

OBJECTIVE

The purpose of this research was to explore the value of reflection and its application to practice through the implementation of educational modules within a new Diabetes Care and Education Master Degree Programme in Kuwait, and to realise how this teaching intervention informs changes in practice.

METHODS

A small exploratory case study was conducted within the Dasman Diabetes Institute, Kuwait. A qualitative approach using focus group interviews was carried out with seventeen participants all of whom are studying on the Diabetes Care and Education Master Degree Programme in Kuwait. An inductive approach to thematic analysis, which focused on examining themes within data, was performed.

RESULTS

The results indicate that participants value the opportunity to study through organised, structured and assessed reflection. The learning provides useful information and support to the participant by highlighting the role which reflection plays to enhance personal and professional development, the value of educational theory, continuing professional development, collaboration and enhancing patient education and practice.

CONCLUSIONS

The significance of reflection is often seen in the literature as an important aspect of professional competence. This research has highlighted the value of reflection as a key component within a new educational programme.

Kuwait National Programme for Healthy Living: first 5-year plan (2013-2017)

The Kuwait National Programme for Healthy Living is an initiative to promote the health and well-being for individuals residing in the country. The plan has been created based on current data and available information pertaining to the various lifestyles of the populations living in Kuwait and their impact on health in general and chronic diseases in particular. Leading a healthy lifestyle is important because it means living in an environment, such as the Kuwaiti society, where chronic conditions such as obesity, diabetes, hypertension and coronary heart diseases are significantly reduced. Several factors regarding lifestyles among the various ethnic groups residing in Kuwait have been identified, including inactivity resulting from the lack of need for physical exertion in daily-life activities and social rituals involving the serving of food amongst the various ethnic groups residing in Kuwait. For Kuwaitis and other ethnicities as well, traditional social gatherings include serving food as an integral element of the social ritual. The environments of school and work also contribute to an individual's lifestyle. The goal of the programme is to address the contribution of lifestyle choices and the social environment to health with the goal of creating a healthy environment that will sustain good health and social well-being. This can be accomplished by involving the various stakeholders in promoting the aim of the programme. Finally, addressing the research needs for healthy lifestyle issues can have a huge impact on the outcome of the programmes designed and would aid in creating a healthy living environment.

Gender differences in ghrelin association with cardiometabolic risk factors in arab population

Ghrelin is a stomach produced hormone that has been shown to have protective role against development of CVD which is a leading cause of death in the Arab world. The objective of this study is to examine the gender difference in association between traditional CVD risk factors and plasma ghrelin among Arabs. 359 Arab residents in Kuwait participated in a cross-sectional survey (≥20 years old): 191 were females and 168 were males. Plasma level of ghrelin was assessed using Luminex-based assay. Ghrelin levels were significantly higher in females (935 ± 78 pg/mL) than males (763 ± 65 pg/mL) (P = 0.0007). Females showed inverse association with WC (r = -0.23, P = 0.001) and HbA1C (r = -0.19, P = 0.0102) as well as SBP (r = -0.15, P = 0.0383) and DBP (r = -0.16, P = 0.0230), respectively. Higher levels of ghrelin were shown to associate with increased insulin resistance, as measured by HOMAIR, in male Arab subjects (P-trend = 0.0202) but not in females. In this study we show that higher ghrelin level was negatively associated with measures of obesity, HbA1C, and blood pressure in females and positively associated with increased insulin resistance in Arab males.

The Kuwait-Scotland eHealth Innovation Network (KSeHIN): a sustainable approach to quality improvement in healthcare

BACKGROUND

The rising prevalence of obesity and diabetes in Kuwait represents a significant challenge for the country's healthcare system. Diabetes care in Scotland has improved by adopting a system of managed clinical networks supported by a national informatics platform. In 2010, a Kuwait-Dundee collaboration was established with a view to transforming diabetes care in Kuwait. This paper describes the significant progress that has been made to date.

METHODS

The Kuwait-Scotland eHealth Innovation Network (KSeHIN) is a partnership among health, education, industry and government. KSeHIN aims to deliver a package of clinical service development, education (including a formal postgraduate programme and continuing professional development) and research underpinned by a comprehensive informatics system.

RESULTS

The informatics system includes a disease registry for children and adults with diabetes. At the patient level, the system provides an overview of clinical and operational data. At the population level, users view key performance indicators based on national standards of diabetes care established by KSeHIN. The national childhood registry (CODeR) accumulates approximately 300 children a year. The adult registry (KHN), implemented in four primary healthcare centres in 2013, has approximately 4000 registered patients, most of whom are not yet meeting national clinical targets. A credit-bearing postgraduate educational programme provides module-based teaching and workplace-based projects. In addition, a new clinical skills centre provides simulator-based training. Over 150 masters students from throughout Kuwait are enrolled and over 400 work-based projects have been completed to date.

CONCLUSION

KSeHIN represents a successful collaboration between multiple stakeholders working across traditional boundaries. It is targeting patient outcomes, system performance and professional development to provide a sustainable transformation in the quality of diabetes healthcare for the growing population of Kuwaitis with diabetes in Kuwait.

Obesity and dental decay: inference on the role of dietary sugar

OBJECTIVE

To evaluate the relationship of children's obesity and dental decay.

METHODS

We measured parameters related to obesity and dental decay in 8,275 4(th) and 5(th) grade Kuwaiti children (average age = 11.36 years) in a cross-sectional study. First to determine body weight, height, age for computation of BMI . Second, to determine numbers of teeth, numbers of fillings and numbers of untreated decayed teeth to determine extent and severity of dental disease. From these measurements, we computed measures of dental decay in children from four body weight categories; obese, overweight, normal healthy weight and underweight children.

RESULTS

The percentage of children with decayed or filled teeth varied inversely with the body weight category. The percentage of decayed or filled teeth decreased from 15.61% (n=193) in underweight children, to 13.03% (n=4,094) in normal healthy weight children, to 9.73% (n=1,786) in overweight children to 7.87% (n=2,202) in obese children. Differences between all groups were statistically significant. Male children in this population had more dental decay than female children but the reduction of tooth decay as a function of BMI was greater in male children.

CONCLUSIONS

The finding of an inverse obesity-dental decay relationship contradicts the obesity-sugar and the obesity-dental decay relationship hypotheses. Sugar is well recognized as necessary and sufficient for dental decay. Sugar is also hypothesized to be a leading co-factor in obesity. If the later hypothesis is true, one would expect dental decay to increase with obesity. This was not found. The reasons for this inverse relationship are not currently clear.

Proteomics analysis of human obesity reveals the epigenetic factor HDAC4 as a potential target for obesity

Sedentary lifestyle and excessive energy intake are prominent contributors to obesity; a major risk factors for the development of insulin resistance, type 2 diabetes and cardiovascular diseases. Elucidating the molecular mechanisms underlying these chronic conditions is of relevant importance as it might lead to the identification of novel anti-obesity targets. The purpose of the current study is to investigate differentially expressed proteins between lean and obese subjects through a shot-gun quantitative proteomics approach using peripheral blood mononuclear cells (PBMCs) extracts as well as potential modulation of those proteins by physical exercise. Using this approach, a total of 47 proteins showed at least 1.5 fold change between lean and obese subjects. In obese, the proteomic profiling before and after 3 months of physical exercise showed differential expression of 38 proteins. Thrombospondin 1 (TSP1) was among the proteins that were upregulated in obese subjects and then decreased by physical exercise. Conversely, the histone deacetylase 4 (HDAC4) was downregulated in obese subjects and then induced by physical exercise. The proteomic data was further validated by qRT-PCR, Western blot and immunohistochemistry in both PBMCs and adipose tissue. We also showed that HDAC4 levels correlated positively with maximum oxygen consumption (VO2 Max) but negatively with body mass index, percent body fat, and the inflammatory chemokine RANTES. In functional assays, our data indicated that ectopic expression of HDAC4 significantly impaired TNF-α-dependent activation of NF-κB, establishing thus a link between HDAC4 and regulation of the immune system. Together, the expression pattern of HDAC4 in obese subjects before and after physical exercise, its correlation with various physical, clinical and metabolic parameters along with its inhibitory effect on NF-κB are suggestive of a protective role of HDAC4 against obesity. HDAC4 could therefore represent a potential therapeutic target for the control and management of obesity and presumably insulin resistance.

Genetic substructure of Kuwaiti population reveals migration history

The State of Kuwait is characterized by settlers from Saudi Arabia, Iran, and other regions of the Arabian Peninsula. The settlements and subsequent admixtures have shaped the genetics of Kuwait. High prevalence of recessive disorders and metabolic syndromes (that increase risk of diabetes) is seen in the peninsula. Understanding the genetic structure of its population will aid studies designed to decipher the underlying causes of these disorders. In this study, we analyzed 572,366 SNP markers from 273 Kuwaiti natives genotyped using the illumina HumanOmniExpress BeadChip. Model-based clustering identified three genetic subgroups with different levels of admixture. A high level of concordance (Mantel test, p=0.0001 for 9999 repeats) was observed between the derived genetic clusters and the surname-based ancestries. Use of Human Genome Diversity Project (HGDP) data to understand admixtures in each group reveals the following: the first group (Kuwait P) is largely of West Asian ancestry, representing Persians with European admixture; the second group (Kuwait S) is predominantly of city-dwelling Saudi Arabian tribe ancestry, and the third group (Kuwait B) includes most of the tent-dwelling Bedouin surnames and is characterized by the presence of 17% African ancestry. Identity by Descent and Homozygosity analyses find Kuwait's population to be heterogeneous (placed between populations that have large amount of ROH and the ones with low ROH) with Kuwait S as highly endogamous, and Kuwait B as diverse. Population differentiation FST estimates place Kuwait P near Asian populations, Kuwait S near Negev Bedouin tribes, and Kuwait B near the Mozabite population. FST distances between the groups are in the range of 0.005 to 0.008; distances of this magnitude are known to cause false positives in disease association studies. Results of analysis for genetic features such as linkage disequilibrium decay patterns conform to Kuwait's geographical location at the nexus of Africa, Europe, and Asia.

Predictive models to assess risk of type 2 diabetes, hypertension and comorbidity: machine-learning algorithms and validation using national health data from Kuwait--a cohort study

OBJECTIVE

We build classification models and risk assessment tools for diabetes, hypertension and comorbidity using machine-learning algorithms on data from Kuwait. We model the increased proneness in diabetic patients to develop hypertension and vice versa. We ascertain the importance of ethnicity (and natives vs expatriate migrants) and of using regional data in risk assessment.

DESIGN

Retrospective cohort study. Four machine-learning techniques were used: logistic regression, k-nearest neighbours (k-NN), multifactor dimensionality reduction and support vector machines. The study uses fivefold cross validation to obtain generalisation accuracies and errors.

SETTING

Kuwait Health Network (KHN) that integrates data from primary health centres and hospitals in Kuwait.

PARTICIPANTS

270 172 hospital visitors (of which, 89 858 are diabetic, 58 745 hypertensive and 30 522 comorbid) comprising Kuwaiti natives, Asian and Arab expatriates.

OUTCOME MEASURES

Incident type 2 diabetes, hypertension and comorbidity.

RESULTS

Classification accuracies of >85% (for diabetes) and >90% (for hypertension) are achieved using only simple non-laboratory-based parameters. Risk assessment tools based on k-NN classification models are able to assign 'high' risk to 75% of diabetic patients and to 94% of hypertensive patients. Only 5% of diabetic patients are seen assigned 'low' risk. Asian-specific models and assessments perform even better. Pathological conditions of diabetes in the general population or in hypertensive population and those of hypertension are modelled. Two-stage aggregate classification models and risk assessment tools, built combining both the component models on diabetes (or on hypertension), perform better than individual models.

CONCLUSIONS

Data on diabetes, hypertension and comorbidity from the cosmopolitan State of Kuwait are available for the first time. This enabled us to apply four different case-control models to assess risks. These tools aid in the preliminary non-intrusive assessment of the population. Ethnicity is seen significant to the predictive models. Risk assessments need to be developed using regional data as we demonstrate the applicability of the American Diabetes Association online calculator on data from Kuwait.

Interaction of osteopontin with IL-18 in obese individuals: implications for insulin resistance

Background/Objective

Osteopontin (OPN) and IL-18 are known inflammatory mediators and both participate in a wide range of biological processes linked to immunological disorders. Since an interaction between OPN and IL-18 has not been studied in obesity, we investigated whether: (i) their levels were simultaneously elevated in obese individuals; (ii) OPN was associated with IL-18 in obese individuals and (iii) their levels associated with fasting blood glucose (FBG) and BMI.

Subjects and Methods

PBMCs and plasma samples were isolated from 60 individuals including lean as well as overweight and obese individuals. Subcutaneous adipose tissue samples were obtained. OPN and IL-18 were measured by ELISA. OPN and IL-18 mRNA expression was quantified by real time quantitative RT-PCR.

Results

Obese individuals exhibited significantly increased circulating OPN levels as compared with lean individuals (obese 2865±101; lean 1681±116 pg/ml; P<0.0001). IL-18 levels were also high in obese individuals (obese 491±39, lean 301±26 pg/ml; P = 0.0009). OPN and IL-18 expression were simultaneously up-regulated (OPN: 5.4-Fold; IL-18: 8.9-Fold; P<0.05) in PBMCs from obese individuals compared to lean group. Adipose tissue from obese individuals had high expression of OPN (7.3-Fold) and IL-18 (9.6-Fold). Plasma OPN levels correlated positively with FBG levels (r = 0.32, P = 0.02). Similarly, IL-18 correlated positively with FBG levels (r = 0.406, P = 0.0042). Stepwise multiple regression analysis showed an independent association of BMI with OPN and IL-18. Interestingly, OPN levels increased progressively with an increase in IL-18 levels (r = 0.52, P = 0.0004). We also examined the regulatory role of IL-18 in OPN secretion from PBMCs. Neutralizing anti-IL-18Rα mAb reduced OPN secretion.

Conclusion

These findings represent the first observation that plasma, PBMC and adipose tissue OPN and IL-18 are simultaneously increased and correlate with each other in overweight/obese individuals which may trigger the development of obesity-associated insulin resistance. Moreover, these results provide the direct evidence that IL-18 regulates OPN production in PBMCs.

Can salivary phosphate levels be an early biomarker to monitor the evolvement of obesity?

Phosphate is an essential nutrient required for important biological reactions that maintain the normal homoeostatic control of the cell. The adverse effects of phosphate metabolism in obesity have not been studied in detail, chiefly because such an association is thought to be uncommon. However, in some animal models of obesity, serum phosphate levels were noted to be higher than the nonobese controls. For example, leptin-deficient (ob/ob) mice become severely obese and have high serum phosphate levels. In this study, we analyzed the phosphate content in saliva collected from children (n = 77; 10.5 ± 1.8) to evaluate association with body mass index; there is a significant increase of salivary phosphate content in obese compared to normal-weight children (ANOVA p < 0.001). The correlation coefficient (r) between BMI and phosphate was 0.33 (p = 0.0032). Our results suggest that the human salivary phosphate level may be an early biomarker of the genesis of obesity in children. The diagnostic importance lies in the fact that the salivary phosphate level could provide a noninvasive predictive marker in the development of obesity. Further studies will be required to understand the underlying mechanism of increased salivary phosphate accumulation in obese and overweight children. Nevertheless, its occurrence without systemic changes could be of diagnostic value, particularly in monitoring evolvement of obesity.

A review of adult obesity prevalence, trends, risk factors, and epidemiologic methods in Kuwait

OBJECTIVE

Kuwait is among the countries with the highest obesity rates worldwide; however, little is known about the state of obesity epidemiology research in Kuwait. In this paper, we therefore review the findings and methodology of studies on the prevalence, trends and risk factors of obesity in Kuwait.

METHODS

The PubMed database was searched using the keyword combination: obesity and adults and Kuwait. Out of 111 articles, 39 remained after abstract review, and 18 were selected after full-text review.

RESULTS

The studies were all cross-sectional and published in the last fifteen years (1997-2012). The sample size ranged from 177 to 38,611 individuals. Only 30% of studies used random sampling. The prevalence (BMI ≥ 30) in studies with a nationally representative sample ranged from 24% to 48% overall and in adults >50 years was greater than 52%. Rates were significantly higher in women than those in men. Studies that examined trends showed an increase in obesity prevalence between 1980 and 2009. Multiple risk factors including sociocultural factors were investigated in the studies; however, factors were only crudely assessed.

CONCLUSION

There is a need for future studies, particularly surveillance surveys and prospective cohort studies utilizing advanced methods, to monitor trends and to comprehensively assess the factors contributing to the obesity epidemic in Kuwait.

Elevated expression of the toll like receptors 2 and 4 in obese individuals: its significance for obesity-induced inflammation

Background

Expression profile of the toll like receptors (TLRs) on PBMCs is central to the regulation of proinflammatory markers. An imbalance in the TLRs expression may lead to several types of inflammatory disorders. Furthermore, the dynamic regulation of inflammatory activity and associated impaired production of cytokines by peripheral blood mononuclear cells (PBMCs) in obese individulas remain poorly understood. Therefore, we determined the perturbation in TLRs (TLR2 and TLR4), their adaptor proteins (MyD88, IRAK1 and TRAF6) expression in PBMCs/subcutaneous adipose tissue (AT) as well as inflammatory cytokines changes in obese individuals.

Methods

mRNA expression levels of TLR2, TLR4, IL-6, TNF-α and adaptor proteins were determined by RT-PCR. TLR2, TLR4 and adaptor proteins expression in AT was determined by immunohistochemistry.

Results

Obese and overweight individuals showed significantly increased expression of TLR2, TLR4 and MyD88 in both PBMCs and AT as compared with lean individuals (P < 0.05). Interestingly, we found a remarkably higher expression of TLRs in obese and overweight individuals with type 2 diabetes (P < 0.05). Increased expression of TLR2, TLR4, MyD88 and IRAK1 correlated with body mass index (BMI) (TLR2: r = 0.91; TLR4: r = 0.88, P <0.0001; MyD88: r = 0.95, P < 0.0001; IRAK1 r = 0.78, P < 0.002). TLRs’ expression was also correlated with fasting blood glucose (FBG) (TLR2: r = 0.61, P < 0.002; TLR4: r = 0.52, P < 0.01) and glycated haemoglobin (HbA1c) ( TLR2: r = 0.44, P <0.03; TLR4: r = 0.48, P < 0.03). Transcript levels of IL-6 and TNF-α were highly elevated in obese subjects compared to lean subjects. There was a strong association of TLRs’ expression in PBMCs with TNF-α (TLR2: r = 0.92; TLR4: r = 0.92; P < 0.0001) and IL-6 (TLR2: r = 0.91, P < 0.0001; TLR4: r = 0.81; P < 0.001). Similarly adaptor proteins were significantly correlated with TNF-α (MyD88: r = 0.9, P < 0.0001; IRAK1: r = 0.86; P < 0.0002) and IL-6 (MyD88: r = 0.91, P < 0.0001; IRAK1: 0.77; P < 0.002).

Conclusions

TLRs and adapter proteins were overexpressed in PBMCs from obese subjects, which correlated with increased expression of TNF-α and IL-6. This association may explain a potential pathophysiological link between obesity and inflammation leading to insulin resistance.