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Task Force on 'Clinical Algorithms for Fracture Risk' commissioned by the American Society for Bone and Mineral Research (ASBMR) Professional Practice Committee has recommended that FRAX® models in the US do not include adjustment for race and ethnicity. This position paper finds that an agnostic model would unfairly discriminate against the Black, Asian and Hispanic communities and recommends the retention of ethnic and race-specific FRAX models for the US, preferably with updated data on fracture and death hazards. In contrast, the use of intervention thresholds based on a fixed bone mineral density unfairly discriminates against the Black, Asian and Hispanic communities in the US. This position of the Working Group on Epidemiology and Quality of Life of the International Osteoporosis Foundation (IOF) is endorsed both by the IOF and the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO).
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Algoritmos , Densidade Óssea , Medicina Baseada em Evidências , Fraturas por Osteoporose , Humanos , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/etnologia , Medição de Risco/métodos , Densidade Óssea/fisiologia , Osteoporose/etnologia , Estados Unidos/epidemiologia , FemininoRESUMO
OBJECTIVES: To evaluate some confounding factors that influence the concentrations of S100 calcium binding protein B (S100B), glial fibrillary acidic protein (GFAP), and ubiquitin carboxyl-terminal hydrolase L-1 (UCH-L1) in older individuals. Indeed, recent guidelines have proposed the combined use of S100B and the "GFAP-UCH-L1" mTBI test to rule out mild traumatic brain injuries (mTBI). As older adults are the most at risk of mTBI, it is particularly important to understand the confounding factors of those mTBI rule-out biomarkers in aging population. METHODS: The protein S100B and the "GFAP and UCH-L1" mTBI test were measured using Liaison XL (Diasorin) and Alinity I (Abbott), respectively, in 330 and 341 individuals with non-suspected mTBI from the SarcoPhAge cohort. RESULTS: S100B, GFAP and UCH-L1 were all significantly correlated with renal function whereas alcohol consumption, Geriatric Depression Score (GDS), smoking habits and anticoagulant intake were not associated with any of these three biomarkers. Body mass index (BMI) and age were associated with GFAP and UCH-L1 expression while sex and mini-mental state examination (MMSE) were only associated with GFAP. According to the manufacturer's cut-offs for mTBI rule-out, only 5.5â¯% of participants were positive for S100B whereas 66.9â¯% were positive for the "GFAP-UCH-L1" mTBI test. All positive "GFAP-UCH-L1" mTBI tests were GFAP+/UCH-L1-. Among individuals with cystatin C>1.55â¯mg/L, 25â¯% were positive for S100B while 90â¯% were positive for the mTBI test. CONCLUSIONS: Our data show that confounding factors have different impacts on the positivity rate of the "GFAP-UCH-L1" mTBI test compared to S100B.
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Free radicals, products of oxidative processes, induce cellular damage linked to diseases like Parkinson's and diabetes due to increased reactive oxygen species (ROS) levels. Catalase, crucial for scavenging ROS, emerges as a therapeutic agent against ailments including atherosclerosis and tumor progression. Its primary function involves breaking down hydrogen peroxide into water and oxygen. Research on catalase-drug interactions reveals structural changes under specific conditions, affecting its activity and cellular antioxidant balance, highlighting its pivotal role in defending against oxidative stress-related diseases. Hence, targeting catalase is considered an effective strategy for controlling ROS-induced cellular damage. This study investigates the interaction between bovine liver catalase and glipizide using spectroscopic and computational methods. It also explores glipizide's effect on catalase activity. More than 20% inhibition of catalase enzymatic activity was recorded in the presence of 50 µM glipizide. To investigate the inhibition of catalase activity by glipizide, we performed a series of binding studies. Glipizide was found to form a complex with catalase with moderate affinity and binding constant in the range of 3.822 to 5.063 × 104 M-1. The binding was spontaneous and entropically favourable. The α-helical content of catalase increased from 24.04 to 29.53% upon glipizide complexation. Glipizide binding does not alter the local environment surrounding the tyrosine residues while a notable decrease in polarity around the tryptophan residues of catalase was recorded. Glipizide interacted with numerous active site residues of catalase including His361, Tyr357, Ala332, Asn147, Arg71, and Thr360. Molecular simulations revealed that the catalase-glipizide complex remained relatively stable in an aqueous environment. The binding of glipizide had a negligible effect on the secondary structure of catalase, and hydrogen bonds persisted consistently throughout the trajectory. These results could aid in the development of glipizide as a potent catalase inhibitor, potentially reducing the impact of reactive oxygen species (ROS) in the human body.
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Bone forming agents, also known as anabolic therapies, are essential in managing osteoporosis, particularly for patients at very high-risk of fractures. Identifying candidates who will benefit the most from these treatments is crucial. For example, this group might include individuals with severe osteoporosis, multiple vertebral fractures, a recent fragility fracture or those unresponsive to antiresorptive treatments. Definitions of patients with a very high fracture risk vary across nations, are often based on fracture history, bone mineral density (BMD), and/or fracture risk calculated by FRAX® or other algorithms. However, for very high-risk patients, anabolic agents such as teriparatide, abaloparatide, or romosozumab are commonly recommended as first-line therapies due to their ability to stimulate new bone formation and improve bone microarchitecture, offering significant benefits in rapid fracture reduction over antiresorptive therapies. The cost-effectiveness of these agents is a critical consideration for decision-makers. Despite their higher costs, their effectiveness in significantly reducing fracture risk and improving quality of life can justify the investment, especially when long-term savings from reduced fracture rates and associated healthcare costs are considered. Additionally, after completing a course of anabolic therapy, transitioning to antiresorptive agents like bisphosphonates or denosumab is crucial to maintain the gains in bone density and minimize subsequent fracture risks. This sequential treatment approach ensures sustained protection and optimal resource utilization. In summary, the effective use of bone forming agents in osteoporosis requires a comprehensive strategy that includes accurate patient identification, consideration of cost-effectiveness, and implementation of appropriate sequential treatments, ultimately maximizing patient outcomes and healthcare efficiency.
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Conservadores da Densidade Óssea , Densidade Óssea , Osteoporose , Humanos , Osteoporose/tratamento farmacológico , Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Fraturas por Osteoporose/prevenção & controle , Anabolizantes/uso terapêutico , Teriparatida/uso terapêutico , Análise Custo-BenefícioRESUMO
Several proteins and peptides tend to form an amyloid fibril, causing a range of unrelated diseases, from neurodegenerative to certain types of cancer. In the native state, these proteins are folded and soluble. However, these proteins acquired ß-sheet amyloid fibril due to unfolding and aggregation. The conversion mechanism from well-folded soluble into amorphous or amyloid fibril is not well understood yet. Here, we induced unfolding and aggregation of hen egg-white lysozyme (HEWL) by reducing agent dithiothreitol and applied mechanical sheering force by constant shaking (1000 rpm) on the thermostat for 7 days. Our turbidity results showed that reduced HEWL rapidly formed aggregates, and a plateau was attained in nearly 5 h of incubation in both shaking and non-shaking conditions. The turbidity was lower in the shaking condition than in the non-shaking condition. The thioflavin T binding and transmission electron micrographs showed that reduced HEWL formed amorphous aggregates in both conditions. Far-UV circular dichroism results showed that reduced HEWL lost nearly all alpha-helical structure, and ß-sheet secondary structure was not formed in both conditions. All the spectroscopic and microscopic results showed that reduced HEWL formed amorphous aggregates under both conditions.
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Amiloide , Muramidase , Animais , Temperatura , Muramidase/química , Amiloide/química , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Galinhas/metabolismoRESUMO
Glycation of biomolecules results in the formation of advanced glycation end products (AGEs). Immunoglobulin G (IgG) has been implicated in the progression of various diseases, including diabetes and cancer. This study purified three IgG subclasses (IgG1, IgG2, and IgG3) from Camelus dromedarius colostrum using ammonium sulfate fractionation and chromatographic procedures. SDS-PAGE was performed to confirm the purity and molecular weight of the IgG subclasses. Several biochemical and biophysical techniques were employed to study the effect of glycation on camel IgG using methylglyoxal (MGO), a dicarbonyl sugar. Early glycation measurement showed an increase in the fructosamine content by ~four-fold in IgG2, ~two-fold in IgG3, and a slight rise in IgG1. AGEs were observed in all classes of IgGs with maximum hyperchromicity (96.6%) in IgG2. Furthermore, glycation-induced oxidation of IgGs led to an increase in carbonyl content and loss of -SH groups. Among subclass, IgG2 showed the highest (39.7%) increase in carbonyl content accompanied by 82.5% decrease in -SH groups. Far UV-CD analysis illustrated perturbation of ß-sheet structure during glycation reaction with MGO. Moreover, glycation of IgG proceeds to various conformational states like aggregation and increased hydrophobicity. In addition, the cytotoxicity assay (MTT) illustrated the proliferation of breast cancer cells (MCF-7) with IgG2 treatment.
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Camelus , Neoplasias , Animais , Reação de Maillard , Óxido de Magnésio , Imunoglobulina G/química , Produtos Finais de Glicação Avançada , Proliferação de CélulasRESUMO
Amyloid fibrils abnormally accumulate together in the human body under certain conditions, which can result in lethal conditions. Thus, blocking this aggregation may prevent or treat this disease. Chlorothiazide (CTZ) is a diuretic and is used to treat hypertension. Several previous studies suggest that diuretics prevent amyloid-related diseases and reduce amyloid aggregation. Thus, in this study we examine the effects of CTZ on hen egg white lysozyme (HEWL) aggregation using spectroscopic, docking, and microscopic approaches. Our results showed that under protein misfolding conditions of 55 °C, pH 2.0, and 600 rpm agitation, HEWL aggregated as evidenced by the increased turbidity and Rayleigh light scattering (RLS). Furthermore, thioflavin-T, as well as trans electron microscope (TEM) analysis confirmed the formation of amyloid structures. An anti-aggregation effect of CTZ is observed on HEWL aggregations. Circular dichroism (CD), TEM, and Thioflavin-T fluorescence show that both CTZ concentrations reduce the formation of amyloid fibrils as compared to fibrillated. The turbidity, RLS, and ANS fluorescence increase with CTZ increasing. This increase is attributed to the formation of a soluble aggregation. As evidenced by CD analysis, there was no significant difference in α-helix content and ß-sheet content between at 10 µM CTZ and 100 µM. A TEM analysis of HEWL coincubated with CTZ at different concentrations validated all the above-mentioned results. The TEM results show that CTZ induces morphological changes in the typical structure of amyloid fibrils. The steady-state quenching study demonstrated that CTZ and HEWL bind spontaneously via hydrophobic interactions. HEWL-CTZ also interacts dynamically with changes in the environment surrounding tryptophan. Computational results revealed the binding of CTZ to ILE98, GLN57, ASP52, TRP108, TRP63, TRP63, ILE58, and ALA107 residues in HEWL via hydrophobic interactions and hydrogen bonds with a binding energy of -6.58 kcal mol-1. We suggest that at 10 µM and 100 µM, CTZ binds to the aggregation-prone region (APR) of HEWL and stabilizes it, thus preventing aggregation. Based on these findings, we can conclude that CTZ has antiamyloidogenic activity and can prevent fibril aggregation.
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Anti-Hipertensivos , Microscopia , Humanos , Animais , Clorotiazida , Muramidase/química , Dicroísmo Circular , Amiloide/metabolismo , Galinhas/metabolismoRESUMO
Alpha-amylase (α-amylase) is a key player in the management of diabetes and its related complications. This study was intended to have an insight into the binding of caffeic acid and coumaric acid with α-amylase and analyze the effect of these compounds on the formation of advanced glycation end-products (AGEs). Fluorescence quenching studies suggested that both the compounds showed an appreciable binding affinity towards α-amylase. The evaluation of thermodynamic parameters (ΔH and ΔS) suggested that the α-amylase-caffeic/coumaric acid complex formation is driven by van der Waals force and hydrogen bonding, and thus complexation process is seemingly specific. Moreover, glycation and oxidation studies were also performed to explore the multitarget to manage diabetes complications. Caffeic and coumaric acid both inhibited fructosamine content and AGE fluorescence, suggesting their role in the inhibition of early and advanced glycation end-products (AGEs). However, the glycation inhibitory potential of caffeic acid was more in comparison to p-coumaric acid. This high antiglycative potential can be attributed to its additional -OH group and high antioxidant activity. There was a significant recovery of 84.5% in free thiol groups in the presence of caffeic acid, while coumaric attenuated the slow recovery of 29.4% of thiol groups. In vitro studies were further entrenched by in silico studies. Molecular docking studies revealed that caffeic acid formed six hydrogen bonds (Trp 59, Gln 63, Arg 195, Arg 195, Asp 197 and Asp 197) while coumaric acid formed four H-bonds with Trp 59, Gln 63, Arg 195 and Asp 300. Our studies highlighted the role of hydrogen bonding, and the ligands such as caffeic or coumaric acid could be exploited to design antidiabetic drugs.
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Ácidos Cumáricos , alfa-Amilases , Produtos Finais de Glicação Avançada/metabolismo , Simulação de Acoplamento Molecular , Compostos de SulfidrilaRESUMO
Background and objective: There is limited information as to the association of several key bone markers with bone mineral density (BMD) in understudied ethnic groups. This study investigated the relationship between circulating levels of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-Β ligand (RANKL) with BMD in Arab postmenopausal women. Materials and methods: In this cross-sectional study, a total of 617 Saudi postmenopausal women from the Osteoporosis Registry of the Chair for Biomarkers of Chronic Diseases were included. Anthropometric data, BMD, and biochemical data were retrieved from the registry. Participants were stratified into three groups based on T-score; n = 169 with osteoporosis, n = 282 with osteopenia, and n = 166 normal. Analysis of bone markers including RANKL, OPG, osteocalcin, and N-terminal telopeptide (NTx) was completed using commercially available bioassays. Results: The results suggested that OPG was significantly and positively correlated with age in the osteoporosis group (r = 0.29, p < 0.05), while it was inversely correlated with BMD femoral neck left (r = −0.56, p < 0.001) and BMD femoral neck right (r = −0.37, p < 0.05) in the same group. Moreover, RANKL showed a significant inverse correlation with NTx in the osteopenia group (r = −0.37, p < 0.05). Furthermore, the RANKL/OPG ratio had a positive and significant correlation with BMI (r = 0.34, p < 0.05), BMD femoral neck left (r = 0.36, p < 0.05) and BMD femoral neck right (r = 0.35, p < 0.05) in the osteopenia group. By contrast, it showed a significant inverse correlation with waist to hip ratio in the osteoporosis group (r = −0.38, p < 0.05). Multiple regression analysis showed that OPG contributes to BMD variations in the osteopenia group (p = 0.03). Conclusions: In conclusion, changes in circulating levels of RANKL and OPG might be a protective mechanism contrary to the increased bone loss in postmenopausal women.
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Doenças Ósseas Metabólicas , Osteoporose , Osteoprotegerina , Ligante RANK , Árabes , Biomarcadores , Densidade Óssea , Estudos Transversais , Feminino , Humanos , Ligantes , Osteoprotegerina/sangue , Pós-Menopausa , Ligante RANK/sangueRESUMO
OBJECTIVE: Both vitamin D and Fe micronutrient deficiencies are common in Saudi Arabia but the association between them is unclear. The present study aimed to determine whether Fe indices are associated with vitamin D status and other metabolic markers in Arab adolescents. DESIGN: Single-centre, cross-sectional study gathering anthropometrics, glucose and lipid profile. Serum 25-hydroxyvitamin D (25(OH)D), Fe, total iron-binding capacity (TIBC), transferrin saturation (%) and other parameters were measured. SETTING: Vitamin D School Project Database, King Saud University (2014-2016). PARTICIPANTS: Arab adolescents aged 10-17 years randomly selected from the Vitamin D School Project Database (170 Saudi students; 100 girls, seventy boys). RESULTS: Among Fe indices, only TIBC was found to be significantly and inversely associated with 25(OH)D (r = -0·20; P < 0·01) and only in girls (r = -0·20; P < 0·05). Among cardiometabolic parameters, serum Fe was associated with TAG in boys (r = 0·36; P < 0·01) and inversely associated with HDL-cholesterol in girls (r = -0·29; P < 0·05). Age was the most significant predictor of serum Fe for all participants, accounting for 5 % (R2 = 0·05; P = 0·004) of variance perceived. Serum 25(OH)D and age, on the other hand, were the most significant predictors for TIBC, accounting for 10·1 % (R2 = 0·10; P < 0·001) of variance perceived. CONCLUSIONS: Among healthy Arab adolescents, the association between vitamin D and Fe indices, particularly TIBC, is modest, inverse and sex-dependent. Larger studies with inclusion of markers such as hepcidin and ferritin, vitamin D metabolites and endogenous sex hormones may provide a clearer view of this complex association.
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Anemia Ferropriva/sangue , Ferro/sangue , Deficiência de Vitamina D/sangue , Vitamina D/sangue , Adolescente , Anemia Ferropriva/epidemiologia , Árabes , Glicemia , Criança , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Lipídeos/sangue , Masculino , Estado Nutricional , Arábia Saudita/epidemiologia , Fatores Sexuais , Vitamina D/análogos & derivados , Deficiência de Vitamina D/epidemiologiaRESUMO
Vitamin B12 deficiency leads to adverse effects on human health, but limited information is available as to whether abnormal vitamin B12 levels are associated between parents and offspring. The present study aimed to assess the association between circulating levels of vitamin B12 in Saudi parents and their children as well as its association with pro-inflammatory markers. A total of 104 Saudi families: 49 fathers, 63 mothers, 94 sons and 79 daughters were selected for the study. Fasting blood samples and anthropometrics were collected. Biochemical parameters, various pro-inflammatory markers and vitamin B12 were measured. Results showed a significant positive correlation between B12 levels in most parent-offspring pairs: mother-daughter (N = 46 pairs, r = 0.72, p < 0.0001); father-daughter (N = 39, r = 0.62, p < 0.0001) and mother-son (N = 51, r = 0.42, p < 0.01). This association was absent in father-son pairs (N = 48, r = 0.26, p = 0.09). Also, B12 was inversely associated with tumor necrosis factor-α and plasminogen activator inhibitor-1 in parents (r = -0.32; p < 0.01 and r = -0.31; p < 0.01 respectively) and children (r = -0.14; p < 0.01 and r = -0.19; p < 0.01 respectively). A significant inverse correlation was found between vitamin B12 and leptin in mothers (r = -0.31, p < 0.05). Our study suggests a strong familial component between B12 levels indicating a possible genetic influence on individual B12 status. Our study also suggests an inverse correlation between circulating levels of vitamin B12 and pro-inflammatory markers. The present study highlights the importance of extending screening in families of patients with abnormal B12 levels and expanding treatment, if necessary, to maximize clinical benefits.
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Deficiência de Vitamina B 12 , Biomarcadores , Criança , Humanos , Pais , Arábia Saudita , Vitamina B 12/metabolismoRESUMO
Quinoline yellow (QY) is a synthetic yellow dye widely used as a coloring agent for various foodstuffs. In the current study, we have examined the role of QY on the aggregation propensity of hen egg-white lysozyme (HEWL) under physiological conditions. The dye induced conformational changes in HEWL leading to aggregate formation were identified by circular dichroism (CD), turbidity analysis, fluorescence measurement and microscopic (TEM) imaging. Molecular docking and molecular dynamics simulation studies were also employed to strengthen binding and aggregation results. Our results indicate that 25-100 µM of QY induces aggregation in HEWL, while lower QY concentrations (5 and 10 µM) does not have any effect on the aggregation propensity of HEWL. The kinetics of HEWL aggregation demonstrate nucleation independent aggregation of HEWL without lag phase. On the other hand, far UV-CD analysis illustrated the loss of α-helical structure with the increasing concentration of QY. TEM results also support the formation of aggregate structures in HEWL when exposed to QY. Molecular docking and simulation studies revealed that the HEWL-QY complex is stable as compared to individual entities. In silico analysis also illustrated that QY-induced aggregation of HEWL proceeds through the formation of hydrogen bonds, electrostatic (Pi-Anion) and Pi-Sulfur interactions. The above-mentioned results highlight the possible detrimental effect by food additive dyes, particularly in protein misfolding.
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Corantes/química , Aditivos Alimentares/química , Muramidase/química , Quinolinas/química , Algoritmos , Animais , Benzotiazóis/química , Galinhas , Dicroísmo Circular , Ligação de Hidrogênio , Cinética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Agregados Proteicos , Ligação Proteica , Estrutura Secundária de Proteína , Espectrofotometria , Eletricidade EstáticaRESUMO
The study aimed to determine whether circulating spexin (SPX) is modified during the course of pregnancy and whether it is affected by the presence of glucose intolerance, i.e., Gestational Diabetes Mellitus (GDM). This prospective study included 102 pregnant women (63 non-GDM and 39 GDM; mean age 29.4⯱â¯5.1â¯years; mean BMI 28.0⯱â¯6.1â¯kg/m2). Anthropometrics, glycemic and lipid profiles, as well measurements of circulating adipocytokines and SPX were measured at baseline and after 3 and 6â¯months. In GDM patients, SPX levels increased significantly after 6-months, in parallel with a borderline significant increase in glucose (pâ¯=â¯0.07). In non-GDM patients, however, median SPX level decreased from baseline to 6-months (pâ¯<â¯0.01), and this change was not associated with changes in glucose levels. Change in glucose from baseline to 6-months was positively associated with change in SPX in GDM patients only (Râ¯=â¯0.37; pâ¯<â¯0.05). SPX levels are positively influenced by glucose intolerance in pregnant women with GDM, while they decrease in control women without GDM.
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Diabetes Gestacional/sangue , Hormônios Peptídicos/sangue , Adipocinas/sangue , Adulto , Glicemia/metabolismo , Feminino , Humanos , Gravidez , Fatores de TempoRESUMO
OBJECTIVE: The present single-center observational study determined the prevalence and coexistence of sarcopenia, pre-sarcopenia, and metabolic syndrome (MetS) among apparently healthy Arab men and whether having both conditions present a unique cardiometabolic profile that is distinct than having the conditions separately. METHODS: A total of 471 out of 530 Arab men aged 20-77 years old were included after screening for the presence of pre-sarcopenia (ALM/ht2 < 7.26 kg/m2), sarcopenia (presence of both low muscle mass and low function), and MetS. MetS screening was done using the definition by the NCEP-ATP III. Based on the screening results, the participants were classified as control (normal) group (N = 328), MetS only (N = 73), pre-sarcopenia only (N = 64), and MetS + pre-sarcopenia (N = 6). RESULTS: Pre-sarcopenia without MetS was observed in 64 participants (13.6%), while MetS without pre-sarcopenia was observed in 73 participants (15.5%). MetS + pre-sarcopenia was observed only in 6 participants (1.3%). None of the participants had sarcopenia. Age- and BMI-adjusted comparisons showed that those with MetS + pre-sarcopenia had the highest diastolic blood pressure and triglyceride levels as compared to all groups (p values < 0.001). MetS + pre-sarcopenia group also had the highest levels of glucose and the lowest lean arms-legs/BMI ratio than control and pre-sarcopenia groups (p values < 0.001 and 0.005, respectively). CONCLUSION: The prevalence of pre-sarcopenia + MetS is low among young adult Arab men, but shows a unique cardiometabolic profile that is worse than those having only one of the conditions. Further investigations should be done among Arab women and the elderly.
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Árabes/estatística & dados numéricos , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Sintomas Prodrômicos , Sarcopenia/complicações , Sarcopenia/epidemiologia , Adulto , Idoso , Composição Corporal/fisiologia , Densidade Óssea , Comorbidade , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Sarcopenia/diagnóstico , Sarcopenia/patologia , Arábia Saudita/epidemiologia , Adulto JovemRESUMO
BACKGROUND: The endoplasmic reticulum enzyme glucose-6-phosphatase catalyzes the common terminal reaction in the gluconeogenic/glycogenolytic pathways and plays a central role in glucose homeostasis. In most mammals, different G6PC subunits are encoded by three paralogous genes (G6PC, G6PC2, and G6PC3). Mutations in G6PC and G6PC3 are responsible for human mendelian diseases, whereas variants in G6PC2 are associated with fasting glucose (FG) levels. RESULTS: We analyzed the evolutionary history of G6Pase genes. Results indicated that the three paralogs originated during early vertebrate evolution and that negative selection was the major force shaping diversity at these genes in mammals. Nonetheless, site-wise estimation of evolutionary rates at corresponding sites revealed weak correlations, suggesting that mammalian G6Pases have evolved different structural features over time. We also detected pervasive positive selection at mammalian G6PC2. Most selected residues localize in the C-terminal protein region, where several human variants associated with FG levels also map. This region was re-sequenced in ~560 subjects from Saudi Arabia, 185 of whom suffering from type 2 diabetes (T2D). The frequency of rare missense and nonsense variants was not significantly different in T2D and controls. Association analysis with two common missense variants (V219L and S342C) revealed a weak but significant association for both SNPs when analyses were conditioned on rs560887, previously identified in a GWAS for FG. Two haplotypes were significantly associated with T2D with an opposite effect direction. CONCLUSIONS: We detected pervasive positive selection at mammalian G6PC2 genes and we suggest that distinct haplotypes at the G6PC2 locus modulate susceptibility to T2D.
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Diabetes Mellitus Tipo 2/genética , Glucose-6-Fosfatase/genética , Haplótipos , Adulto , Idoso , Animais , Evolução Molecular , Feminino , Glucose-6-Fosfatase/metabolismo , Humanos , Invertebrados/enzimologia , Invertebrados/genética , Masculino , Pessoa de Meia-Idade , Filogenia , Polimorfismo de Nucleotídeo Único , Arábia Saudita , Análise de Sequência de DNA , Vertebrados/genética , Adulto JovemRESUMO
BACKGROUND: The present randomized clinical trial characterized the beneficial effects of a multi-strain probiotics supplementation on improving circulating endotoxin levels (primary endpoint) and other cardiometabolic biomarkers (secondary endpoint) in patients with T2DM. METHODS: A total of 78 adult Saudi T2DM patients (naïve and without co-morbidities) participated in this clinical trial and were randomized to receive twice daily placebo or probiotics [(2.5 × 109 cfu/g) containing the following bacterial strains: Bifidobacterium bifidum W23, Bifidobacterium lactis W52, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus casei W56, Lactobacillus salivarius W24, Lactococcus lactis W19 and Lactococcus lactis W58 (Ecologic®Barrier)] in a double-blind manner for 12 weeks. Anthropometrics and cardiometabolic profiles were obtained at baseline and after 12/13 weeks of treatment. RESULTS: After 12/13 weeks of intervention and using intention-to-treat analysis, no difference was noted in endotoxin levels between groups [Placebo - 9.5% vs. Probiotics - 52.2%; (CI - 0.05 to 0.36; p = 0.15)]. Compared with the placebo group however, participants in the probiotics groups had a significant but modest improvement in WHR [Placebo 0.0% vs. Probiotics 1.11%; (CI - 0.12 to - 0.01; p = 0.02)] as well as a clinically significant improvement in HOMA-IR [Placebo - 12.2% vs. Probiotics - 60.4%; (CI - 0.34 to - 0.01; p = 0.04)]. CONCLUSION: Using a multi-strain probiotic supplement daily for 12/13 weeks significantly improved HOMA-IR and modestly reduced abdominal adiposity among medication naïve T2DM patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01765517 , Registered January 10, 2013.
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Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Suplementos Nutricionais , Endotoxinas/sangue , Hipoglicemiantes/uso terapêutico , Miocárdio/metabolismo , Probióticos/uso terapêutico , Antropometria , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Análise de Intenção de Tratamento , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , PlacebosRESUMO
BACKGROUND: Altered expression of receptor tyrosine kinases (RTKs) is a major driver of growth and metastasis of cancers. Recepteur d'origine nantais (RON) receptor is a single-pass transmembrane RTK aberrantly expressed in a number of cancers. Efforts to block deregulated RON signaling in tumors using small molecule kinase inhibitors or antibodies are complicated by the presence of unknown number/types of isoforms of RON, which, despite having similar sequences, are localized differently and mediate varied functions. The objective of this study was to identify splice variants of RON transcripts between exons 1 and 10 that code for the extracellular region. METHODS: Direct cDNA sequencing was performed for the transcript between exons 1-10 of RON by Sanger sequencing in various lung cancer cell lines. RESULTS: PCR amplification and bi-directional sequencing of cDNA for section between exons 1 and 10 from lung cancer cell lines revealed the presence of several splice variants of RON transcripts; the variants were formed by skipping of exons 2, 2-3, 5-6, 6 and 8-9. Each of these transcript variants were found in one or more cell lines. While the variants formed by skipping of exons 2, 2-3 and 5-6 resulted in loss of 63, 106 and 109 amino acids, respectively, and didn't cause reading-frameshift, the transcripts formed by skipping of exons 6 and 8-9 caused reading-frameshift. Splice variant lacking exons 8-9 was found in 13 out of 23 cell lines tested. CONCLUSION: Lung cancer cell lines contain several splice variants of RON which involve skipping of exons coding for extracellular region. Some of the splicing changes result in reading-frameshift and the N-terminally truncated isoforms are expected to be secreted out. The ubiquitous nature of alternative splicing events in RON suggests the need for isoform specific approaches to functional analysis and therapeutic targeting of RON.
Assuntos
Espaço Extracelular/genética , Neoplasias Pulmonares/genética , Reação em Cadeia da Polimerase/métodos , Isoformas de Proteínas/genética , Receptores Proteína Tirosina Quinases/genética , Análise de Sequência de DNA/métodos , Linhagem Celular Tumoral , HumanosRESUMO
BACKGROUND: Overweight adults are at increased risk for cardiovascular disease and vitamin D deficiency, whereas an important feature to vitamin D physiology is its sex dependence. The aim of this study was to examine whether vitamin D status improvement exerts a sexually dimorphic effect on serum proteins associated with cardiovascular risk among overweight adults. MATERIALS AND METHODS: Unprocessed serum from age- and BMI-matched men (n = 26) and premenopausal women (n = 24) with vitamin D deficiency and after they achieved sufficiency through a 12-month nutritional intervention was analysed using our previously published depletion-free quantitative proteomics method. Key findings were verified with ELISA. Differentially expressed proteins were subjected to in silico bioinformatics assessment using principal component analysis, hierarchical clustering and Metacore™ pathway analysis. All mass spectrometry proteomic data are available via ProteomeXchange (identifier: PXD003663). RESULTS: A total of 282 proteins were differentially expressed after the intervention between men and women (P-value ≤ 0·05), in which the blood coagulation pathway was significantly enriched. In agreement with the proteomics findings, ELISA measurements showed vitamin K-dependent protein C, von Willebrand factor, fibrinogen gamma chain and multimerin-1 proteins, of relevance to blood coagulation, to be differentially affected (P-value ≤ 0·05) between sexes after vitamin D status correction. CONCLUSIONS: This study identified novel protein-level molecular indicators on the sexually dimorphic effect of vitamin D status correction associated with blood coagulation among overweight adults. These sex-mediated vitamin D effects should be factored in the design and interpretation of vitamin D observational and interventional studies testing cardiometabolic outcomes.
Assuntos
Proteínas Sanguíneas/metabolismo , Fibrinogênio/metabolismo , Sobrepeso/metabolismo , Proteína C/metabolismo , Deficiência de Vitamina D/metabolismo , Vitamina D/análogos & derivados , Fator de von Willebrand/metabolismo , Adulto , Coagulação Sanguínea , Estudos de Casos e Controles , Simulação por Computador , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Espectrometria de Massas , Sobrepeso/complicações , Análise de Componente Principal , Proteômica , Fatores Sexuais , Resultado do Tratamento , Vitamina D/metabolismo , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/dietoterapia , Adulto JovemRESUMO
BACKGROUND: Irisin is a recently identified myokine that plays an important role in preventing obesity and insulin resistance. We investigated whether the common FNDC5 (irisin precursor) gene variants influence susceptibility to obesity and type 2 diabetes (T2D) and verified the impact of FNDC5 gene variants on serum irisin levels, glucose and lipid metabolism in a Saudi population. METHODS: Genomic DNA from 814 (394 T2DM and 414 controls) subjects were genotyped for the five common SNPs (rs3480A/G, rs1746661G/T, rs1298190A/G, rs726344A/G and rs1570569G/T) of the FNDC5 gene using the TaqMan genotyping assay. Biochemical parameters and hematic concentrations of irisin and insulin as well as anthropometric indices were collected. RESULTS: Serum irisin levels were higher in T2DM patients compared to controls (p < 0.0001). Analyses of FNDC5 SNPs showed that: 1) The rs3480 GG associates with decreased risk of obesity (p = 0.005; odds ratio: 0.48) and lower body mass index (BMI) values (p = 0.03). In addition, GGAAG was identified as the protective haplotype against risk of obesity (p = 0.001; odds ratio: 0.23). 2) The rs1746661 G allele associates with higher triglyceride (TG) levels (p = 0.019). 3) The rs157069 TT genotype associates with higher fasting insulin (p = 0.029) and HOMA-IR (p = 0.002) as well as with lower circulating irisin levels (p = 0.016). CONCLUSIONS: SNPs in FNDC5 gene correlates with obesity and glucose-lipid metabolism possibly because they modulate the serum levels of irisin.
Assuntos
Glicemia/genética , Fibronectinas/genética , Metabolismo dos Lipídeos/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Árabes/genética , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/genética , Feminino , Fibronectinas/metabolismo , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Arábia SauditaRESUMO
BACKGROUND: Obesity is a recognized risk factor for various cardiometabolic diseases and several indices are used clinically to assess overall cardiometabolic risk. This study aims to determine the sensitivity of six anthropometric indices [Body mass index (BMI), waist, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body adiposity index (BAI) and visceral adiposity index (VAI)] in determining diabetes mellitus type 2, coronary heart disease, dyslipidemia, hypertension and metabolic syndrome (MetS) in Saudi adults recruited from two independent cohorts (2008-2009 and 2013-2014). METHODS: A total of 6,821 Saudi adults [2008-2009, N = 3,971 (1,698 males and 2,273 females); 2013-2014, N = 2,850 (926 males and 1,924 females)] aged 18-70 years old were included in this descriptive, cross-sectional study. Anthropometrics were obtained and fasting blood samples analyzed for glucose and lipids. BMI, WHR, WHtR, BAI and VAI were computed mathematically. RESULTS: VAI was the most sensitive index in determining DMT2 (AUC 0.72; p < 0.001) in the 2008-2009 cohort and MetS (AUC = 0.84; p < 0.001) in the 2013-2014 cohort. WHR was most discriminating for CHD in both cohorts (AUC 0.70 and 0.84 for 2008-2009 and 2013-2014, p values <0.001, respectively). WHtR was most sensitive but rather modest in determining hypertension (AUC 0.66; p < 0.001), while waist circumference was most sensitive for dyslipidemia (AUC 0.72; p < 0.001) in the 2008-2009 cohort and MetS (AUC 0.85; p < 0.001) in the 2013-2014 cohort. BAI was the least sensitive adiposity index. CONCLUSION: Sensitivity of adiposity indices regarding cardiometabolic diseases highlight the importance of body fat distribution in determining overall cardiometabolic risk, with indices involving abdominal obesity being more clinically significant than BMI and BAI. The sensitivity of these adiposity indices should be noted in assessing a particular cardiometabolic disease.