Sherif H. Abd-Alrahman

Whole Serum 3D LC-nESI-FTMS Quantitative Proteomics Reveals Sexual Dimorphism in the Milieu Intérieur of Overweight and Obese Adults

Linking gender-specific differences to the molecular etiology of obesity has been largely based on genomic and transcriptomic evidence lacking endophenotypic insight and is not applicable to the extracellular fluid compartments, or the milieu intérieur, of the human body. To address this need, this study profiled the whole serum proteomes of age-matched nondiabetic overweight and obese females (n = 28) and males (n = 31) using a multiplex design with pooled biological and technical replicates. To bypass basic limitations of immunodepletion-based strategies, subproteome enrichment by size-exclusion chromatography (SuPrE-SEC) followed by iTRAQ 2D-LC-nESI-FTMS analysis was used. The study resulted in the reproducible analysis of 2472 proteins (peptide FDR < 5%, q < 0.05). A total of 248 proteins exhibited significant modulation between men and women (p < 0.05) that mapped to pathways associated with β-estradiol, lipid and prostanoid metabolism, vitamin D function, immunity/inflammation, and the complement and coagulation cascades. This novel endophenotypic signature of gender-specific differences in whole serum confirmed and expanded the results of previous physiologic and pharmacologic studies exploring sexual dimorphism at the genomic and transcriptomic level in tissues and cells. Conclusively, the multifactorial and pleiotropic nature of human obesity exhibits sexual dimorphism in the circulating proteome of importance to clinical study design.

Fenugreek extract as an inducer of cellular death via autophagy in human T lymphoma Jurkat cells

BackgroundDrugs used both in classical chemotherapy and the more recent targeted therapy do not have cancer cell specificity and, hence, cause severe systemic side effects. Tumors also develop resistance to such drugs due to heterogeneity of cell types and clonal selection. Several traditional dietary ingredients from plants, on the other hand, have been shown to act on multiple targets/pathways, and may overcome drug resistance. The dietary agents are safe and readily available. However, application of plant components for cancer treatment/prevention requires better understanding of anticancer functions and elucidation of their mechanisms of action. The current study focuses on the anticancer properties of fenugreek, a herb with proven anti-diabetic, antitumor and immune-stimulating functions.MethodJurkat cells were incubated with 30 to 1500 μg/mL concentrations of 50% ethanolic extract of dry fenugreek seeds and were followed for changes in viability (trypan blue assay), morphology (microscopic examination) and autophagic marker LC3 transcript level (RT-PCR).ResultsIncubation of Jurkat cells with fenugreek extract at concentrations ranging from 30 to 1500 μg/mL for up to 3 days resulted in cell death in a dose- and time-dependent manner. Jurkat cell death was preceded by the appearance of multiple large vacuoles, which coincided with transcriptional up-regulation of LC3. GC-MS analysis of fenugreek extract indicated the presence of several compounds with anticancer properties, including gingerol (4.82%), cedrene (2.91%), zingerone (16.5%), vanillin (1.52%) and eugenol (1.25%).ConclusionsDistinct morphological changes involving appearance of large vacuoles, membrane disintegration and increased expression of LC3 transcripts indicated that fenugreek extract induced autophagy and autophagy-associated death of Jurkat cells. In addition to the already known apoptotic activation, induction of autophagy may be an additional mechanism underlying the anticancer properties of fenugreek. This is the first report showing fenugreek as an inducer of autophagy in human cells and further work is needed to define the various intermediates of the autophagic pathway.

Residue and dissipation kinetics of thiamethoxam in a vegetable-field ecosystem using QuEChERS methodology combined with HPLC–DAD

The dissipation kinetics and residual levels of thiamethoxam in potato and soil under field ecosystem were determined using a QuEChERS method with HPLC-DAD. At fortification levels of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg kg(-1), it was shown recovery was 99.4% (95.3-103.5%) for potato tubers, and 88.5% (86-91%) for soil with coefficient variation of the method (CV%) was less than 4% in potato tubers, and in soil less than 11%. For repeatability ranged from 1.27% to 4.77%. The LOD and LOQ were estimated to be 0.02 and 0.06 mg kg(-1), respectively. The half-lives were 2.92 and 1.4 days, respectively. The terminal residues of thiamethoxam were below the maximum residue limit (MRL 0.2 mg kg(-1)) after 6 days, which considered to be safe for human beings. These results contribute to establishing the scientific basis of the dosage of thiamethoxam for use in vegetable-field ecosystems.

Strong Associations Between the Pesticide Hexachlorocyclohexane and Type 2 Diabetes in Saudi Adults

Pesticide exposure has been implicated as an environmental risk factor for the development of type 2 diabetes mellitus (T2DM). The aim of this study was to investigate the association of the body burden of the pesticide hexachlorocyclohexane (HCH) with the risk of T2DM in a sample of adults from Saudi Arabia. Serum samples were obtained from 280 adult subjects. Hexachlorocyclohexane isomer residues were measured by high-resolution gas chromatography-mass spectrometry. Data on lifestyle, dietary habits, and health status were gathered. Associations between exposure and T2DM were analyzed by logistic regression. Around 49% of adults enrolled in this study were diagnosed with T2DM. Among various HCH isomers, serum concentrations of the pesticides β and γ-HCH were most strongly and consistently linked to T2DM in our studied subjects. Associations of HCH varied across five components of the metabolic syndrome. It positively and significantly associated with four out of the five components, especially elevated triglycerides, high fasting glucose, high blood pressure and HOMA-IR but negatively and significantly with HDL-cholesterol. This study in line with earlier ones about diabetes associated with HCH pesticide exposure and proposes possible hormonal pathways worthy of further investigation.

Urinary Iodine is Associated with Insulin Resistance in Subjects with Diabetes Mellitus Type 2

BACKGROUND Diabetes Mellitus (DM) is a major health problem worldwide and its prevalence in Saudi Arabia has reached 31.6%. Patients with diabetes mellitus are at an increased risk of thyroid disease. The purpose of this study was to examine the urinary excretion of iodine in type 2 DM (T2DM) patients, and to assess the clinical implication of iodine status on T2DM. METHODS A total of 266 adult Saudis aged 18-55 years (109 T2DM patients and 157 healthy controls) were randomly selected from the Riyadh Cohort Study. Subjects were assessed for anthropometry, morning blood chemistries including fasting glucose, and lipid profile; serum concentrations of leptin, adiponectin, resistin, insulin, aPAI, hsCRP, Ang II, TNF-α, TSH, T3, T4, urine creatinine, urine iodine were measured using specific assays. RESULTS The concentration of urine iodine was significantly lower in T2DM than in healthy control subjects (84.6±2.3 vs. 119.4±3.4, p<0.001), which remained significant after creatinine correction and controlling for age (p=0.01). Furthermore, urinary iodine is negatively correlated with waist, hips, SAD, glucose, insulin, HOMA-IR triglyceride, resistin, angiotensin II (Ang II), and CRP, while it was positively associated with TSH. CONCLUSIONS The decreased levels of iodine concentration in T2DM patients and its likely deleterious effects on metabolic functions calls for a systematic approach to thyroid disease screening in diabetic patients. Routine annual urinary iodine determination is recommended and should target T2DM patients at risk of thyroid dysfunction.

Blood thiamine and its phosphate esters as measured by high-performance liquid chromatography: Levels and associations in diabetes mellitus patients with varying degrees of microalbuminuria

Background: Thiamine deficiency has been linked to microvascular complications in patients with diabetes mellitus (DM). In this study, we aim to assess blood and urine thiamine status by high performance liquid chromatography (HPLC) in patients with DM Type 1 and Type 2 (DMT1, DMT2) and to identify associations with markers of incipient nephropathy and kidney dysfunction. Subjects and methods: A total of 205 subjects (43 DMT1 and 162 DMT2) with and without microalbuminuria and 26 non-diabetic controls were included. Fasting blood samples were collected and anthropometric parameters were measured. Fasting blood, lipid and renal profile were determined routinely. Blood thiamine concentration, its phosphate esters and urine thiamine were quantified using HPLC. Results: Blood thiamine concentrations (ng 1-1) were decreased by 75.7% and 49.6% in patients with DMT1 and DMT2, respectively [controls (54.8±11.4); DMT1 (41.5±17.9); DMT2 (27.2±12.7), p<0.001]. Among those with normo-albuminuria, urinary excretion of thiamine was significantly increased to 390.1 µg/ml and 1212.4 µg/ml in DMT1 and DMT2 respectively, as compared to controls (326.4 µg/ml). DMT1 and DMT2 patients with micro-albuminuria on the other hand had 2.5- and 3.4-fold increase in urinary excretion of thiamine compared to controls. Conclusion: Low levels of blood thiamine are present in patients with DMT1 and DMT2, and are associated with increased thiamine clearance.

Increased IL-4 mRNA expression and poly-aromatic hydrocarbon concentrations from children with asthma

BackgroundAsthma is the most common chronic childhood disease. Imbalance of cytokines released from T helper cells and environmental factors, such as exposure to poly-aromatic hydrocarbon (PAH), play pivotal roles in the pathogenesis of asthma. The aim of this study was to compare the mRNA expression patterns of Interleukin (IL)-4, interferon (IFN)-γ and Acyl Co A long chain 3 (ACSL3) in peripheral blood leukocytes of children with and without asthma. To correlate the obtained mRNA data with serum IL-4, IFN-γ and PAH levels. Further, to determine the effect of in vivo exposure to PAH on mRNA expression of IL-4, IFN-γ and ACSL3 genes in a rat model.MethodsA total of 170 children below 16 years (85 pediatric asthma patients and 85 matched healthy controls) were randomly selected from the Riyadh Cohort, Saudi Arabia. Gene expression analysis was performed using qRTPCR. Serum IL-4, IFN-γ and PAH were measured using LINCOplex (human multiplex immunoassay kit) and HPLC respectively.ResultsIL-4 mRNA expression was significantly increased (P < 0.05) in children with asthma compared to healthy control group whereas no differences were observed for either IFN-γ or ACSL3 mRNA. Similarly, serum IL- 4 and PAHs concentration was significantly higher as well in children with asthma in whom IFN-γ was also significantly lower. Results obtained in rats showed that exposure to the benzopyrene prototype PAH resulted in a 2.6 fold (P < 0.001) increased IL-4 mRNA expression in blood.ConclusionPeripheral blood IL-4 mRNA levels, serum concentration of this cytokine are elevated in children with asthma. Also, elevated levels of PAH were observed in children with asthma. Additionally, PAH administration in rodents resulted in an increased IL-4 mRNA which is supposed to partly mediate the inflammatory response noted in asthma.

Metabolic Benefits of Six-month Thiamine Supplementation in Patients With and Without Diabetes Mellitus Type 2.

Thiamine deficiency has been documented to be prevalent in patients with diabetes mellitus, and correction of thiamine deficiency in this population may provide beneficial effects in several cardiometabolic parameters, including prevention of impending complications secondary to chronic hyperglycemia. In this interventional study, we aim to determine whether thiamine supplementation is associated with cardiometabolic improvements in patients with diabetes mellitus type 2 (DMT2). A total of 86 subjects (60 DMT2 and 26 age- and BMI-matched controls) were included and were given thiamine supplements (100 mg/day) for six months. Anthropometrics and metabolic profiles were measured routinely. Serum thiamine and its derivatives were measured using high performance liquid chromatography. In all groups, there was a significant decrease in total cholesterol after three months (p = 0.03) as well as in HDL cholesterol after six months of thiamine supplementation (p = 0.009). Significant improvements were also observed in the mean serum levels of creatinine (p = 0.001), as well as thiamine and its derivatives in both serum and urinary levels across follow-up visits (p-values 0.002 and <0.001, respectively). In the DMT2 group, improvements were observed in lipid profile (mean serum LDL and total cholesterol with ^-values 0.008 and 0.006, respectively), serum thiamine (p < 0.001), TMP (p < 0.001), TDP (p < 0.001), urinary thiamine (p < 0.001) and serum creatinine (p < 0.001). Thiamine supplementation is a promising adjuvant therapy for patients with DMT2. Longer clinical trials are needed to determine its protective effect in DMT2 complications.

Thiamine and its phosphate esters in relation to cardiometabolic risk factors in Saudi Arabs

BackgroundThiamine deficiency has suggested to be linked to several insulin-resistance complications. In this study, we aim to associate circulating thiamine levels among cardiometabolic parameters in an Arab cohort using a simple, sensitive, rapid and selective high-performance liquid chromatography (HPLC) method that has recently been developed.MethodsA total of 236 randomly selected, consenting Saudi adult participants (166 males and 70 females) were recruited and screened for the presence of the metabolic syndrome (MetS) using the modified National Cholesterol Education Program–Adult Treatment Panel III definition. Blood thiamine and its derivatives were quantified using HPLC.ResultsA total of 140 participants (53.9%) had MetS. The levels of thiamine and its derivatives of those with MetS were not significantly different from those without. However, hypertensive subjects had significantly higher urinary thiamine (P = 0.03) as well as significantly lower levels of thiamine diphosphate (TDP) (P = 0.01) and total thiamine (P = 0.02) than the normotensive subjects, even after adjusting for age and body mass index (BMI). Furthermore, age- and BMI-matched participants with elevated blood glucose levels had significantly lower levels of thiamine monophosphate (P = 0.020), TDP (P < 0.001) and total thiamine (P < 0.001) and significantly elevated levels of urinary thiamine (P = 0.005) compared to normoglycemic participants.ConclusionsLow thiamine levels are associated with elevated blood glucose and hypertension in Saudi adults. Determination of thiamine status may be considered and corrected among patients with, or at high risk for, MetS, but the question whether thiamine deficiency correction translates to improved cardiometabolic status needs further longitudinal investigation.

Efficacy of Vitamin D interventional strategies in saudi children and adults

Despite the amount of sunshine in Saudi Arabia, vitamin D (25(OH)D) deficiency is highly prevalent among Saudis. Several strategies are known to improve 25(OH)D status. The aim of this study was to evaluate the efficacy of different interventional strategies in improving 25(OH)D status in Saudi children and adults. This interventional study was undertaken among 593 out of 1152 Saudi subjects [530 students (aged 13-17 years) and 63 teachers (aged 26-46 years)] over a 6-month period from different secondary schools in Riyadh, Saudi Arabia. 25(OH)D status was taken at baseline and after 6 months post interventions. Subjects were divided into 3 groups and requested to implement different vitamin D correction schemes: sun-exposure, vitamin D-fortified milk consumption, and oral vitamin D supplementation (1000IU/day). Follow-up results revealed that all correction strategies used could decrease the deficiency of serum 25(OH)D with different potencies, with the highest positive percentage change observed in oral supplementation in both adults and children (11% men, 17% women, 16% boys and 8% girls). The oral vitamin D supplementation strategy also showed significant positive associations between delta (Δ) changes and HDL-cholesterol in both adults and children. In conclusion, oral vitamin D supplementation was the most effective strategy in improving vitamin D status in Saudi adults and children than sunlight exposure or consumption of vitamin D-fortified dairy products.