COVID-19-induced immune thrombocytopenia management approach: A case report and literature review.

Key Clinical Message: Vincristine therapy can be effective in refractory Immune thrombocytopenia (ITP) following COVID-19 vaccination. Our case report highlights the need for further research to establish standard management guidelines for COVID-19-vaccine-associated ITP. Abstract: Adult immune thrombocytopenia (ITP) can occur as a rare complication following several viral infections or a rare adverse event or complication of vaccination. In this paper, we report a case of a 39-year-old male patient with severe refractory ITP that began 4-weeks after receiving his third (booster) dose of the COVID-19 vaccine (BNT162b2, Pfizer-BioNTech). He was given oral dexamethasone 40 mg daily for 4 days followed by prednisone at 1 mg/kg (85 mg daily) for 10 days. In the following weeks, we attempted several other lines of therapy to treat his ITP, including anti-RhD immunoglobulin, which, unfortunately, caused moderate hemolysis requiring packed red blood cell transfusion, intravenous immunoglobulin (given at a subtherapeutic dose of 0.4 g/kg for only 1 day since it was not available), rituximab, and eltrombopag. The patient, unfortunately, showed no response to any of these treatments. This was an indicator to initiate salvage therapy with vincristine 2 mg weekly for 3 weeks. The patient's platelet count started to increase remarkably during the third week of vincristine and normalized after 4 weeks. We review the findings, clinical characteristics, and management approaches that were reported in the literature regarding COVID-19-vaccine-induced ITP. More in-depth research is needed to delineate standard guidelines for the management of such cases. This report underscores the importance of resorting to vincristine and eltrombopag as great options for severe and refractory ITP related to the COVID-19 vaccine.

[Retracted] Effects of nutrients on matrix metalloproteinases in human T­lymphotropic virus type 1 positive and negative malignant T­lymphocytes.

Subsequently to the publication of the above article, a concerned reader drew to the attention of the Editorial Office and the authors that certain pairings of the GAPDH western blotting control bands in Fig. 4 appeared to be strikingly similar to adjacent pairings of bands within the same gel slices; moreover, data bands featured in the HuT­2, C91­PL and Jurkat zymography blots in Fig. 5 also appeared to be remarkably similar, both comparing the bands within a given gel slice (as in the case of the Jurkat cell experiment in Fig. 5) or comparing between gel slices (as in the case of the Hut­2 cells compared with the C910PL cells in Fig. 5). The Editorial Office independently investigated these concerns, and reached the conclusion that the bands did appear strikingly similar; too similar for the appearance of the bands within these figures to have arisen by chance. Moreover, the application of a software analysis program revealed that certain of the data in Fig. 6 had also appeared in another paper published by several of the same authors in another journal at around the same time. As a result of this investigation, the Editor of International Journal of Oncology has decided that this paper should be retracted from the journal on account of a lack of confidence in the authenticity of the presented data. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a satisfactory reply. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Oncology 45: 2159­2166, 2014; DOI: 10.3892/ijo.2014.2638].

Omega 3 fatty acids - Potential modulators for oxidative stress and inflammation in the management of sickle cell disease

Abstract Objective Sickle cell disease is characterized by clinical complications resulting in vaso-occlusive crisis with prominent attributes of oxidative stress, inflammation, and pain. Inflammation is an integral part of this disease which further exacerbates the pain during a crisis. Omega-3 fatty acids are known to possess anti-inflammatory and anti-aggregatory properties and assist in diminishing the slow physiological inactivation. Methods A pilot nutritional interventional study was conducted wherein forty-three children with sickle cell disease aged 5-16 years were supplemented with omega-3 fatty acids for a period of six months. Analysis of oxidative stress, as well as inflammatory parameters, was done pre and post-supplementation. Results Increased free oxygen radical transference values depicting free radical generation is enhanced in these patients along with a reduced antioxidant defense, as seen by decreased free oxygen radical defense values. Supplementation with omega-3 fatty acids for a period of six months significantly reduced the inflammatory marker homocysteine in all patients, whereas high sensitive C reactive protein was significantly reduced only in females of the age group 11-16years. Simultaneously a significant reduction in oxidative stress parameters with a concomitant increase of antioxidant defense was observed in all patients. Conclusion The authors' findings suggest the regulatory effects of omega-3 fatty acids as cellular activators in alleviating the complications due to sickle cell disease. Omega-3 fatty acids hold promise as future therapeutic candidates in patients with sickle cell disease.

Omega 3 fatty acids - Potential modulators for oxidative stress and inflammation in the management of sickle cell disease.

OBJECTIVE: Sickle cell disease is characterized by clinical complications resulting in vaso-occlusive crisis with prominent attributes of oxidative stress, inflammation, and pain. Inflammation is an integral part of this disease which further exacerbates the pain during a crisis. Omega-3 fatty acids are known to possess anti-inflammatory and anti-aggregatory properties and assist in diminishing the slow physiological inactivation. METHODS: A pilot nutritional interventional study was conducted wherein forty-three children with sickle cell disease aged 5-16 years were supplemented with omega-3 fatty acids for a period of six months. Analysis of oxidative stress, as well as inflammatory parameters, was done pre and post-supplementation. RESULTS: Increased free oxygen radical transference values depicting free radical generation is enhanced in these patients along with a reduced antioxidant defense, as seen by decreased free oxygen radical defense values. Supplementation with omega-3 fatty acids for a period of six months significantly reduced the inflammatory marker homocysteine in all patients, whereas high sensitive C reactive protein was significantly reduced only in females of the age group 11-16years. Simultaneously a significant reduction in oxidative stress parameters with a concomitant increase of antioxidant defense was observed in all patients. CONCLUSION: The authors' findings suggest the regulatory effects of omega-3 fatty acids as cellular activators in alleviating the complications due to sickle cell disease. Omega-3 fatty acids hold promise as future therapeutic candidates in patients with sickle cell disease.

Amotosalen and ultraviolet A light treatment efficiently inactivates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in human plasma.

BACKGROUND AND OBJECTIVES: During the ongoing pandemic of COVID-19, SARS-CoV-2 RNA was detected in plasma and platelet products from asymptomatic blood donors, raising concerns about potential risk of transfusion transmission, also in the context of the current therapeutic approach utilizing plasma from convalescent donors. The objective of this study was to assess the efficacy of amotosalen/UVA light treatment to inactivate SARS-CoV-2 in human plasma to reduce the risk of potential transmission through blood transfusion. METHODS: Pools of three whole-blood-derived human plasma units (630-650 ml) were inoculated with a clinical SARS-CoV-2 isolate. Spiked units were treated with amotosalen/UVA light (INTERCEPT Blood System™) to inactivate SARS-CoV-2. Infectious titres and genomic viral load were assessed by plaque assay and real-time quantitative PCR. Inactivated samples were subject to three successive passages on permissive tissue culture to exclude the presence of replication-competent viral particles. RESULTS: Inactivation of infectious viral particles in spiked plasma units below the limit of detection was achieved by amotosalen/UVA light treatment with a mean log reduction of >3·32 ± 0·2. Passaging of inactivated samples on permissive tissue showed no viral replication even after 9 days of incubation and three passages, confirming complete inactivation. The treatment also inhibited NAT detection by nucleic acid modification with a mean log reduction of 2·92 ± 0·87 PFU genomic equivalents. CONCLUSION: Amotosalen/UVA light treatment of SARS-CoV-2 spiked human plasma units efficiently and completely inactivated >3·32 ± 0·2 log of SARS-CoV-2 infectivity, showing that such treatment could minimize the risk of transfusion-related SARS-CoV-2 transmission.

Impact of omega-3 fatty acids on calorie intake and certain anthropometric measurements in children with sickle cell disease in Saudi Arabia.

The nutritional status and growth in children with sickle cell disease is compromised due to intake of diet that is low in calories as well as deficient in nutrients. Growth stunting and a low body mass index have been observed in these children. Some children exhibit pica, which is an abnormal eating pattern by ingesting things other than food, like paper, wood etc. This also was found to correlate to lower hemoglobin values. Interventions with certain essential nutrients such as omega-3 fatty acids are known to benefit these children in terms of lowering their complications due to the disease. We therefore wished to see if omega-3 fatty acids exhibit positive effects on their nutritional intake and growth parameters too. Hence, we supplemented these children with omega-3 fatty acids for a period of six months. Both the male and female children with the disease significantly improved their calorific intake as well as body mass index. Also a lowering of pica status was distinctly observed.

Computational and Kinetic Studies of Acetylcholine Esterase Inhibition by Phenserine.

BACKGROUND: The inhibition of cholinesterase enzymes is one of the promising strategies to manage several neurological disorders that include Alzheimer's disease (AD). MATERIAL AND METHODS: In the current article, we estimated the potential inhibition of acetyl cholinesterase (AChE) by phenserine using slightly modified Ellman assay. To find out the binding interactions of phenserine with the catalytic site of AChE, a molecular docking study was also performed. RESULTS: Phenserine was found to inhibit Electrophorus electricus AChE in a dose-dependent manner with an IC50 value of 0.013 µM. The kinetic analyses indicate that phenserine inhibits AChE in a mixed type manner (competitive and uncompetitive) with Ki values of 0.39 µmole/l and 0.21 µmole/l, respectively. On the other hand, Km and Vmax values were found to be 0.17 µM and 0.39 µM, respectively. The molecular docking studies indicate efficient binding of phenserine through 6 hydrogen bonds, 4 pi-alkyl interactions, and 1 pi-pi interaction within the AChE catalytic pocket. CONCLUSION: Results of our computational and kinetics studies indicated a mixed type inhibition by phenserine at AChE catalytic site.

Correction to: Current therapies in alleviating liver disorders and cancers with a special focus on the potential of vitamin D.

[This corrects the article DOI: 10.1186/s12986-018-0251-5.].

Current therapies in alleviating liver disorders and cancers with a special focus on the potential of vitamin D.

Background: Liver dysfunction is a topic of global concern with many advancing therapies being researched. Though vitamin D takes a center place, other therapies especially nutritional are also gaining ground. Vitamin D has gone beyond its role in skeletal disorders by showcasing its associations in other metabolic dysfunctions too. Result: Epidemiological evidences show a correlation between the status of vitamin D and different forms of cancer. Vitamin D receptors and alterations in gene expression appear decisive in the development of chronic liver disorders. Nutritional status therefore plays a significant role in avoiding the complications related to liver dysfunctions, making it mandatory in maintaining vitamin D sufficiency in the body. Therapies with omega-3 fatty acids, antioxidants, amino acids, steroids also render benefits which could be further explored. Recent research on the progression of certain forms of liver cancer using vitamin D analogs like Seocalcitol EB 1089 has shown good promise. Conclusion: The anti-inflammatory and immuno- regulatory properties of vitamin D makes its analogs, suitable candidates of better choice for the prevention and treatment of liver disorders and cancer.

Inactivation of Middle East respiratory syndrome-coronavirus in human plasma using amotosalen and ultraviolet A light.

BACKGROUND: Middle East respiratory syndrome-coronavirus (MERS-CoV) is a novel zoonotic pathogen. Although the potential for MERS-CoV transmission through blood transfusion is not clear, MERS-CoV was recognized as a pathogen of concern for the safety of the blood supply especially after its detection in whole blood, serum, and plasma of infected individuals. Here we investigated the efficacy of amotosalen and ultraviolet A light (UVA) to inactivate MERS-CoV in fresh-frozen plasma (FFP). STUDY DESIGN AND METHODS: Pooled FFP units were spiked with a recent clinical MERS-CoV isolate. Infectious and genomic viral titers were determined in plasma before and after inactivation with amotosalen/UVA treatment by plaque assay and reverse transcription-quantitative polymerase chain reaction, respectively. In addition, residual replicating or live virus after inactivation was examined by passaging in the permissive Vero E6 cells. RESULTS: The mean MERS-CoV infectious titer in pretreatment samples was 4.67 ± 0.25 log plaque-forming units (pfu)/mL, which was reduced to undetectable levels after inactivation with amotosalen/UVA demonstrating a mean log reduction of more than 4.67 ± 0.25 pfu/mL. Furthermore, inoculation of inactivated plasma on Vero E6 cells did not result in any cytopathic effect (CPE) even after 7 days of incubation and three consecutive passages, nor the detection of MERS RNA compared to pretreatment samples which showed complete CPE within 2 to 3 days postinoculation and log viral RNA titer ranging from 9.48 to 10.22 copies/mL in all three passages. CONCLUSION: Our data show that amotosalen/UVA treatment is a potent and effective way to inactivate MERS-CoV infectious particles in FFP to undetectable levels and to minimize the risk of any possible transfusion-related MERS-CoV transmission.

Pleomorphism and drug resistant cancer stem cells are characteristic of aggressive primary meningioma cell lines.

BACKGROUND: Meningioma tumors arise in arachnoid membranes, and are the most reported central nervous system (CNS) tumors worldwide. Up to 20% of grade I meningioma tumors reoccur and currently predictive cancer stem cells (CSCs) markers for aggressive and drug resistant meningiomas are scarce. METHODS: Meningioma tissues and primary cell lines were investigated using whole transcriptome microarray analysis, immunofluorescence staining of CSCs markers (including CD133, Sox2, Nestin, and Frizzled 9), and drug treatment with cisplatin or etoposide. RESULTS: Unsupervised hierarchical clustering of six meningioma samples separated tissues into two groups. Analysis identified stem cells related pathways to be differential between the two groups and indicated the de-regulation of the stem cell associated genes Reelin (RELN), Calbindin 1 (CALB1) and Anterior Gradient 2 Homolog (AGR2). Immunofluorescence staining for four tissues confirmed stemness variation in situ. Biological characterization of fifteen meningioma primary cell lines concordantly separated cells into two functionally distinct sub-groups. Pleomorphic cell lines (NG type) grew significantly faster than monomorphic cell lines (G type), had a higher number of cells that express Ki67, and were able to migrate aggressively in vitro. In addition, NG type cell lines had a lower expression of nuclear Caspase-3, and had a significantly higher number of CSCs co-positive for CD133+ Sox2+ or AGR2+ BMI1+. Importantly, these cells were more tolerant to cisplatin and etoposide treatment, showed a lower level of nuclear Caspase-3 in treated cells and harbored drug resistant CSCs. CONCLUSION: Collectively, analyses of tissues and primary cell lines revealed stem cell associated genes as potential targets for aggressive and drug resistant meningiomas.

Comparative study of fatty-acid composition of table eggs from the Jeddah food market and effect of value addition in omega-3 bio-fortified eggs.

Health consciousness has increased the desire of people around the world to consume functional foods. Omega-3 essential fatty acids are one among these beneficial and important health supplements without which a general predisposition to degenerative and stress related disorders can occur. Saudi Arabia has shown an alarming increase in obesity (Al-Nozha et al., 2005), diabetes (Alqurashi et al., 2011), and cardiovascular disease (Al-Nozha et al., 2004) in the last few decades mainly due to nutritional transitions and lifestyle alterations (Amuna and Zotor, 2008). Lack of nutrient dense foods and the prevailing food related disorder of obesity (Popkin, 2001; Prentice, 2014) especially render egg as a choice food to be value-added for attaining nutritional security in Saudi Arabia and in effect reverse the increasing incidences of lifestyle diseases. Nutritional intervention through a commonly consumed food product would be an important step in improving the health of the people, and reducing health care costs. As eggs are a frequently consumed food item in Saudi Arabia, enriching them with omega-3 fatty acids would be an excellent way to alleviate the existing problems. A significant deposition of omega-3 fatty acids in the eggs was observed when the diet of hens was supplemented with omega-3 fatty acids from either flaxseed or fish oil source. Inadequacy of omega-3 fatty acids could thus be rectified by producing omega-3 enriched eggs from hens supplemented with flaxseed or fish oil source, and thus contribute toward better health choice of the consumer.

A putative association of interleukin-10 promoter polymorphisms with cardiovascular disease.

Interleukin-10 (IL-10) is an anti inflammatory cytokine involved in the ongoing coronary inflammation and related patho-physiological processes. The piece of work presented herein is aimed at investigating possible association of polymorphisms in IL-10 promoter with Saudi cardiovascular disease (CVD) patients. The study included 80 confirmed CVD patients with diabetes and 75 healthy control individuals both men and women. Concentration of IL-10 in the serum samples were measured by ELISA method. For single nucleotide polymorphism (SNP) analysis, Sanger method of DNA sequencing was followed. The IL-10 level was found to be significantly elevated in CVD patients (P < 0.001) and its associated complications viz. ST-elevation myocardial infarction [STEMI] (P <0.01), non ST-elevation myocardial infarction [NSTEMI] (P < 0.05), and unstable angina [UA] (P < 0.001). We also observed a significant association between polymorphisms in IL-10 promoter at -1082 and -819 locus with Saudi CVD patients. Moreover, at -1082 A/G locus, AA haplotype was found to be less frequent in the CVD patients compared with control individuals. On the other hand, highly significant rise in heterozygous (A/G genotype) condition was observed in patient samples compared with control ones (P < 0.001). Similarly, the genotypic frequencies at -819 C/T locus were also found to be significantly associated (P < 0.001) with CVD patients compared with control individuals. Our study provides the status of polymorphism in IL-10 promoter and its association with CVD risk in Saudi population. As per our information, ours is the first article that shows the genetic diversity in IL-10 promoters and its level in the Saudi CVD patients. © 2017 IUBMB Life, 69(7):522-527, 2017.

Reduction in CD16/CD56 and CD16/CD3/CD56 Natural Killer Cells in Coronary Artery Disease.

BACKGROUND: Natural killer (NK) cells are the potential modulators of inflammatory reactions that exert several unique biological effects and could lead to future adverse events of coronary artery disease (CAD). HYPOTHESIS: The purpose of this study was to find out the possible association of modulation in NK cell, TNK cells, T cells, B cells, and tumor necrosis factor alpha (TNF-α) in CAD patients and various forms of myocardial infarction. METHODS: The present study included total 190 subjects (98 confirmed CAD patients both men and women and 92 healthy control individuals). Serum concentration of TNF-α was measured by ELISA method. For the measurement of various immune cells, viz., NK cell, TNK cells, T cells, and B cells, flow-cytometric analysis was performed. RESULTS: A significant reduction by 15% (P < 0.001) in CD16/CD56 NK cells was observed in CAD patients. Moreover, non-ST segment elevation myocardial infarction (NSTEMI), ST segment elevation myocardial infarction (STEMI), unstable angina (UA), and combined UA + NSTEMI group also showed a significant decline in NK cells compared with control individuals. CD16/CD56/CD3 TNK cells showed a significant reduction in CAD, NSTEMI, STEMI, and UA categories. However, UA + NSTEMI group did not show any significant change in TNK cells. On the other hand, the level of TNF-α was found to be significantly elevated in CAD, STEMI, and UA groups. NSTEMI and combined UA + NSTEMI group did not show any significant change in TNF-α level. CONCLUSION: Current study provides an insight toward the association of immune cells and inflammation with CAD.

Estimation of Interleukin-1ß Promoter (-31 C/T and -511 T/C) Polymorphisms and Its Level in Coronary Artery Disease Patients.

Interleukin-1ß (IL-1ß) is an inflammation-causing cytokine that exerts several unique biological effects and could lead to future adverse events of CAD. The piece of work presented herein is aimed at investigating possible association of IL-1ß levels to its polymorphic site viz. -511 and -31 at promoter region in Saudi CAD patients. The study included 155 confirmed CAD patients and 80 healthy control individuals both men and women. Concentration of IL-1ß in the patients' serum was measured by ELISA method. For single nucleotide polymorphism (SNP) analysis, sanger method of DNA sequencing was followed. We observed variable numbers of SNPs at -31 C/T and -511 T/C promoter regions in Saudi patients suffering from CAD in comparison to the control set of individuals. However, the changes in the number of SNP-hotspots were determined to be non-significant with reference to the control set. The haplotype analysis at -31 and -511 also did not show any significant changes between control and CAD patients. Moreover, serum IL-1ß levels were observed to be expressively higher in patients suffering from CAD (P < 0.001) and its associated complications viz. STEMI (P < 0.001), NSTEMI (P < 0.001), and UA (P < 0.001). Our study provides the status of SNPs at IL-1ß promoter in Saudi population. As per our information, ours is the first article that shows the genetic diversity in IL-1ß promoters and its level in the Saudi CAD patients. J. Cell. Biochem. 118: 2977-2982, 2017. © 2017 Wiley Periodicals, Inc.

Assessment of IL-18 Serum Level and Its Promoter Polymorphisms in the Saudi Coronary Artery Disease (CAD) Patients.

The purpose of the current study was to find out the possible changes polymorphic site at the promoter region of IL-18 gene in Saudi CAD patients. We have also measured serum IL-18 level to find out, the likely association between its level and polymorphic site. The present study included total 197 subjects (98 confirmed CAD patients both men and women and 99 healthy control individuals). Serum concentration of IL-18 was measured by enzyme linked immuno-sorbent assay. For SNPs analysis, sanger method of DNA sequencing was followed. We observed variable numbers of SNPs at -137 C/G, -607 A/C, and -656 T/G promoter sites in our studied samples. However, the observed changes in the number of SNP hotspots were found to be non-significant compared with control. IL-18 level was found to be significantly (P < 0.001) elevated in CAD patients compared with control individuals. The highest rise of around 36% (P < 0.001) in IL-18 level was recorded in unstable angina (UA) patients. Moreover, the group belonging to UA and non-ST segment elevation myocardial infarction (NSTEMI) showed only 6% rise. On the basis of our result, inflammation seems to have a role in the pathogenesis of CAD but not leading to the significant changes at the genetic level. J. Cell. Biochem. 118: 1849-1854, 2017. © 2017 Wiley Periodicals, Inc.

Assessment of genetic diversity in IL-6 and RANTES promoters and their level in Saudi coronary artery disease patients.

BACKGROUND: The present study consisted of a total of 200 subjects (100 confirmed coronary artery disease (CAD) patients), both men and women, and 100 healthy control individuals. METHODS: Serum concentration of IL-6 and RANTES were measured by enzyme-linked immunosorbent assay kit. For SNPs analysis, sanger method of DNA sequencing was followed. RESULTS: We observed variable numbers of SNP sites at -174 G/C, -572 G/C, and -597 G/A in IL-6 and -28 C/G and -109 C/T in RANTES promoters in CAD patients compared with control individuals. However, the observed changes in the number of SNPs were found to be non-significant compared with control individuals. The IL-6 level was found to be significantly (P<.001) elevated in CAD patients compared with control. Moreover, RANTES serum level did not show any significant change in CAD patients. CONCLUSION: Based on our result, it is quite clear that inflammation has a role in the pathogenesis of CAD but does not lead to significant changes at the genetic level in our population. As far as our knowledge goes, this is the first report that shows the genetic diversity in IL-6 and RANTES promoters and their respective levels in Saudi CAD patients.

Spontaneous preterm birth and single nucleotide gene polymorphisms: a recent update.

BACKGROUND: Preterm birth (PTB), birth at <37 weeks of gestation, is a significant global public health problem. World-wide, about 15 million babies are born preterm each year resulting in more than a million deaths of children. Preterm neonates are more prone to problems and need intensive care hospitalization. Health issues may persist through early adulthood and even be carried on to the next generation. Majority (70 %) of PTBs are spontaneous with about a half without any apparent cause and the other half associated with a number of risk factors. Genetic factors are one of the significant risks for PTB. The focus of this review is on single nucleotide gene polymorphisms (SNPs) that are reported to be associated with PTB. RESULTS: A comprehensive evaluation of studies on SNPs known to confer potential risk of PTB was done by performing a targeted PubMed search for the years 2007-2015 and systematically reviewing all relevant studies. Evaluation of 92 studies identified 119 candidate genes with SNPs that had potential association with PTB. The genes were associated with functions of a wide spectrum of tissue and cell types such as endocrine, tissue remodeling, vascular, metabolic, and immune and inflammatory systems. CONCLUSIONS: A number of potential functional candidate gene variants have been reported that predispose women for PTB. Understanding the complex genomic landscape of PTB needs high-throughput genome sequencing methods such as whole-exome sequencing and whole-genome sequencing approaches that will significantly enhance the understanding of PTB. Identification of high risk women, avoidance of possible risk factors, and provision of personalized health care are important to manage PTB.

Endocrine disruption: In silico perspectives of interactions of di-(2-ethylhexyl)phthalate and its five major metabolites with progesterone receptor.

BACKGROUND: Di-(2-ethylhexyl)phthalate (DEHP) is a common endocrine disrupting compound (EDC) present in the environment as a result of industrial activity and leaching from polyvinyl products. DEHP is used as a plasticizer in medical devices and many commercial and household items. Exposure occurs through inhalation, ingestion, and skin contact. DEHP is metabolized to a primary metabolite mono-(2-ethylhexyl)phthalate (MEHP) in the body, which is further metabolized to four major secondary metabolites, mono(2-ethyl-5-hydroxyhexyl)phthalate (5-OH-MEHP), mono(2-ethyl-5-oxyhexyl)phthalate (5-oxo-MEHP), mono(2-ethyl-5-carboxypentyl)phthalate (5-cx-MEPP) and mono[2-(carboxymethyl)hexyl]phthalate (2-cx-MMHP). DEHP and its metabolites are associated with developmental abnormalities and reproductive dysfunction within the human population. Progesterone receptor (PR) signaling is involved in important reproductive functions and is a potential target for endocrine disrupting activities of DEHP and its metabolites. This study used in silico approaches for structural binding analyses of DEHP and its five indicated major metabolites with PR. METHODS: Protein Data bank was searched to retrieve the crystal structure of human PR (Id: 1SQN). PubChem database was used to obtain the structures of DEHP and its five metabolites. Docking was performed using Glide (Schrodinger) Induced Fit Docking module. RESULTS: DEHP and its metabolites interacted with 19-25 residues of PR with the majority of the interacting residues overlapping (82-95 % commonality) with the native bound ligand norethindrone (NET). DEHP and each of its five metabolites formed a hydrogen bonding interaction with residue Gln-725 of PR. The binding affinity was highest for NET followed by DEHP, 5-OH-MEHP, 5-oxo-MEHP, MEHP, 5-cx-MEPP, and 2-cx-MMHP. CONCLUSION: The high binding affinity of DEHP and its five major metabolites with PR as well as a high rate of overlap between PR interacting residues among DEHP and its metabolites and the native ligand, NET, suggested their disrupting potential in normal PR signaling, resulting in adverse reproductive effects.

Human sex hormone-binding globulin as a potential target of alternate plasticizers: an in silico study.

BACKGROUND: Currently, alternate plasticizers are used to replace phthalate plasticizers in children's toys, medical equipments and food packaging, due to the adverse effects of phthalate compounds on human health and laws prohibiting their use. Current information regarding the safety and potential adverse effects of alternate plasticizers is limited and recent studies have found alternate plasticizers to display similar characteristics to those observed in phthalate plasticizers. This study was undertaken to evaluate and predict the potential endocrine disrupting activity of the three most commonly used alternate plasticizers: di(2-ethylhexyl)terephthalate (DEHT), tris(2-ethylhexyl)trimellitate (TOTM), and diisononyl hexahydrophthalate (DINCH) against human sex hormone-binding globulin (SHBG) using in silico approaches. MATERIALS AND METHODS: The crystal structure of human SHBG (Id: 1D2S) was retrieved from Protein Data Bank. PubChem database was searched for the structures of alternate plasticizers, DEHT, TOTM, and DINCH. Docking was performed using Glide (Schrodinger) Induced Fit Docking module. RESULTS: Induced Fit Docking of three alternate plasticizer compounds indicated that each of the three compounds fitted well into the steroid binding pocket of SHBG. Docking displays showed interactions of alternate plasticizers with 25-30 amino-acid residues of SHBG; 18-20 amino residues overlapped between the natural ligand, DHT, and the three compounds (commonality of 82-91 %). The hydrogen-bonding interaction of the amino-acid residue, Asn-82, of SHBG was also present in displays of DHT and all the three alternate phthalates. The binding affinity of all the three alternate phthalates was higher than DHT; maximum in DINCH followed by TOTM and DEHT. CONCLUSION: Our results suggested that the three alternate plasticizers have potential to engage the important interacting residues of SHBG and thus interfere in its steroid homeostatic function.