The silent tragic reality of anaemia, and neural-tube defects (NTDs) in India.

arising from nutritional iron-, folate-, and vitamin-B-deficiencies is exceedingly common in India and has profound negative impacts on anaemia, on pregnancy, and on embryonic-foetal neurodevelopment which predisposes to NTDs and psychological-psychiatric manifestations in childhood. Whereas younger-to-middle-aged Indians fail to perform at maximum potential, the elderly are at risk for calamitous neurologic events. However, these micronutrient-deficiencies are eminently correctable through food-fortification.

Potential for elimination of folate and vitamin B deficiency in India using vitamin-fortified tea: a preliminary study.

Introduction: The majority of Indian women have a poor dietary folate and vitamin B intake resulting in their chronically low vitamin status, which contributes to anaemia and the high incidence of folate-responsive neural-tube defects (NTDs) in India. Although many countries have successfully deployed centrally-processed folate-fortified flour for prevention of NTDs, inherent logistical problems preclude widespread implementation of this strategy in India. Because tea-the second most common beverage worldwide (after water)-is consumed by most Indians every day, and appeared an ideal vehicle for fortification with folate and vitamin B, we determined if daily consumption of vitamin-fortified tea for 2 months could benefit young women of childbearing-age in Sangli, India.

Folate Deficiency Facilitates Genomic Integration of Human Papillomavirus Type 16 DNA In Vivo in a Novel Mouse Model for Rapid Oncogenic Transformation of Human Keratinocytes.

Background: Epidemiologic and in vitro studies suggest independent linkages between poor folate and/or vitamin B-12 nutrition, genomic human papillomavirus (HPV) type 16 viral integration, and cancer. However, there is no direct evidence in vivo to support the causative role of poor folate nutrition in HPV16 integration into the cellular genome.

Objective: We tested the hypothesis that folate deficiency enables the integration of HPV16 into the genome of HPV16-harboring keratinocytes, and could thereby influence earlier transformation of these cells to cancer in an animal model.

Evidence for potential underestimation of clinical folate deficiency in resource-limited countries using blood tests.

Although a low serum folate concentration is a useful biomarker of pure folate deficiency, the presence of vitamin B12 deficiency or hemolysis or both in individuals with low folate status predictably raises serum folate levels. Therefore, in resource-limited settings where dietary folate deficiency can coexist with vitamin B12 deficiency or malaria or both, the serum folate concentration can range from normal to high, leading to serious underestimation of tissue folate status. This review traces the genesis of an inappropriate overreliance on the serum folate concentration to rule out folate deficiency in vulnerable populations of women and children.

Evidence Favoring a Positive Feedback Loop for Physiologic Auto Upregulation of hnRNP-E1 during Prolonged Folate Deficiency in Human Placental Cells.

Previously, we determined that heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) functions as an intracellular physiologic sensor of folate deficiency. In this model, l-homocysteine, which accumulates intracellularly in proportion to the extent of folate deficiency, covalently binds to and thereby activates homocysteinylated hnRNP-E1 to interact with folate receptor-α mRNA; this high-affinity interaction triggers the translational upregulation of cell surface folate receptors, which enables cells to optimize folate uptake from the external milieu. However, integral to this model is the need for ongoing generation of hnRNP-E1 to replenish homocysteinylated hnRNP-E1 that is degraded.

Influence of physiologic folate deficiency on human papillomavirus type 16 (HPV16)-harboring human keratinocytes in vitro and in vivo.

Although HPV16 transforms infected epithelial tissues to cancer in the presence of several co-factors, there is insufficient molecular evidence that poor nutrition has any such role. Because physiological folate deficiency led to the intracellular homocysteinylation of heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) and activated a nutrition-sensitive (homocysteine-responsive) posttranscriptional RNA operon that included interaction with HPV16 L2 mRNA, we investigated the functional consequences of folate deficiency on HPV16 in immortalized HPV16-harboring human (BC-1-Ep/SL) keratinocytes and HPV16-organotypic rafts. Although homocysteinylated hnRNP-E1 interacted with HPV16 L2 mRNA cis-element, it also specifically bound another HPV16 57-nucleotide poly(U)-rich cis-element in the early polyadenylation element (upstream of L2L1 genes) with greater affinity.

Cloning, expression and characterization of mouse (Mus musculus) nicotinamide 5'-mononucleotide adenylyltransferase-2.

Nicotinamide adenine dinucleotide (NAD+) is synthesized by the action of nicotinamide mononucleotide adenylyltransferase (NMNAT) from NMN and ATP. The mouse homolog of NMNAT-2 (mmNMNAT-2) was cloned, expressed, and subsequently identified using MALDI-TOF in conjunction with the ProFound database. Circular dichroism analyses of recombinant mmNMNAT-2 showed α helical and β sheet secondary structures, consistent with the known structure of the human isoform.

Incrimination of heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) as a candidate sensor of physiological folate deficiency.

The mechanism underlying the sensing of varying degrees of physiological folate deficiency, prior to adaptive optimization of cellular folate uptake through the translational up-regulation of folate receptors (FR) is unclear. Because homocysteine, which accumulates intracellularly during folate deficiency, stimulated interactions between heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) and an 18-base FR-α mRNA cis-element that led to increased FR biosynthesis and net up-regulation of FR at cell surfaces, hnRNP-E1 was a plausible candidate sensor of folate deficiency. Accordingly, using purified components, we evaluated the physiological basis whereby L-homocysteine triggered these RNA-protein interactions to stimulate FR biosynthesis.

In utero physiology: role of folic acid in nutrient delivery and fetal development.

Despite the isolation of placental folate receptors 25 y ago and progress in defining the mechanism of folate delivery, considerable gaps remain in the literature for each level of the maternal-placental-fetal unit. Although a critical role of placental folate receptors in maternal-to-fetal folate transport was shown by use of the isolated perfused-placental cotyledon model a decade ago, in vivo confirmation is still needed. Knockout of folate receptors in mice, and knock-down of folate receptors by delivery of antisense oligonucleotides at gestation day 8 or antibodies to folate receptor, results in profound developmental abnormalities in the fetus, ranging from neural tube defects to neurocristopathies such as cleft-lip and cleft-palate, cardiac septal defects, and eye defects.

Incidence of neural tube defects in the least-developed area of India: a population-based study.

Hospital-based records from major cities of India, where roughly a quarter of the population resides, identified the frequency of neural tube defects (NTDs) as ranging from 3.9 to 8.8 per 1000 births, but the incidence in rural areas is unknown.

Behavioral effects of prenatal folate deficiency in mice.

Background: Folate supplementation decreases the incidence of birth defects such as neural tube defects (NTDs). We and others have shown that gestational dietary folate deficiency that does not produce overt NTDs can alter fetal neural histology. Accordingly, murine offspring were examined for the possible functional consequences of prenatal folate deficiency.

Maternal folate deficiency results in selective upregulation of folate receptors and heterogeneous nuclear ribonucleoprotein-E1 associated with multiple subtle aberrations in fetal tissues.

Background: Homocysteine, which increases in folate deficiency, can upregulate folate receptors (FR) at the translational level by increasing the interaction between a short cis-element in the 5'-untranslated region of FR-alpha mRNA and heterogeneous nuclear ribonucleoprotein-E1 (hnRNP-E1). Perturbation of this RNA-protein interaction on GD8.5 induces neural tube defects and neurocristopathies in mice.

Pteroyl-gamma-glutamate-cysteine synthesis and its application in folate receptor-mediated cancer cell targeting using folate-tethered liposomes.

Cell membrane-associated folate receptors are selectively overexpressed in certain human tumors. The high affinity of folic acid for folate receptors provides a unique opportunity to use folic acid as a targeting ligand to deliver chemotherapeutic agents to cancer cells. Folate-tethered liposomes bearing pteroyl-gamma-glutamate-cysteine-polyethylene glycol (PEG)-distearoylphosphatidylethanolamine (DSPE) as the targeting component are under investigation as mediators of drug and gene delivery to cancer cells that overexpress folate receptors.

Antisense modulation of the coding or regulatory sequence of the folate receptor (folate binding protein-1) in mouse embryos leads to neural tube defects.

Background: Although folic acid decreases the incidence of neural tube defects (NTDs) in humans, the mechanism for this protection is unknown. We have employed antisense technology to alter expression of the gene for the folate receptor (folate binding protein-1 [Folbp1]) in mouse embryos cultured in vitro.

Methods: Embryos were explanted on day 8 of gestation and cultured for 44 hr.

Characterization of human brain nicotinamide 5'-mononucleotide adenylyltransferase-2 and expression in human pancreas.

NMNAT (nicotinamide 5'-mononucleotide adenylyltransferase; EC 2.7.7.

Myocardial infarction/injury is relatively common at presentation of acute thrombotic thrombocytopenic purpura: the Indiana University experience.

Although widespread vascular thrombosis is common in thrombotic thrombocytopenic purpura (TTP), there have been no prospective studies on the extent of injury to specific organs. Following successful resuscitation and plasma exchange of an index patient with widespread organ dysfunction, cardiogenic shock, and elevated cardiac troponin-I levels, we prospectively studied and identified 2 more individuals (of 10 consecutive patients) with evidence of myocardial injury/infarction at presentation of acute TTP. These data suggest that cardiac troponin-I measurements should be considered during initial evaluation of all patients with acute TTP.