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Publication
Journal: Current Biology
December/3/2001
Abstract
Nijmegen breakage syndrome (NBS) is a rare human disease displaying chromosome instability, radiosensitivity, cancer predisposition, immunodeficiency, and other defects [1, 2]. NBS is complexed with MRE11 and RAD50 in a DNA repair complex [3-5] and is localized to telomere ends in association with TRF proteins [6, 7]. We show that blood cells from NBS patients have shortened telomere DNA ends. Likewise, cultured NBS fibroblasts that exhibit a premature growth cessation were observed with correspondingly shortened telomeres. Introduction of the catalytic subunit of telomerase, TERT, was alone sufficient to increase the proliferative capacity of NBS fibroblasts. However, NBS, but not TERT, restores the capacity of NBS cells to survive gamma irradiation damage. Strikingly, NBS promotes telomere elongation in conjunction with TERT in NBS fibroblasts. These results suggest that NBS is a required accessory protein for telomere extension. Since NBS patients have shortened telomeres, these defects may contribute to the chromosome instability and disease associated with NBS patients.
Publication
Journal: FEBS Letters
September/14/2010
Abstract
Telomeres are essential structures at the ends of eukaryotic chromosomes. Work on their structure and function began almost 70 years ago in plants and flies, continued through the Nobel Prize winning work on yeast and ciliates, and goes on today in many model and non-model organisms. The basic molecular mechanisms of telomeres are highly conserved throughout evolution, and our current understanding of how telomeres function is a conglomeration of insights gained from many different species. This review will compare the current knowledge of telomeres in plants with other organisms, with special focus on the functional length of telomeric DNA, the search for TRF homologs, the family of POT1 proteins, and the recent discovery of members of the CST complex.
Publication
Journal: Molecular Nutrition and Food Research
October/27/2008
Abstract
Tocotrienol-rich fraction (TRF) of palm oil has been shown to possess potent antioxidant, anticancer, and cholesterol lowering activities. In this study, our aim was to examine the effects of TRF on LPS-induced inflammatory response through measuring the production of inflammatory mediators, namely nitric oxide (NO), prostaglandin E(2) (PGE(2)), inducible nitric oxide synthase (iNOS), cytokines (TNF-alpha, IL-4, and IL-8), cyclooxygenase-1 and -2 (COX-1 and COX-2), and nuclear factor-kappaB (NF-kappaB) in human monocytic (THP-1) cells. At concentrations 0.5-5.0 microg/mL, TRF dose-dependently protected against LPS-induced cell death. At same concentrations, TRF also showed potent anti-inflammatory activity as demonstrated by a dose-dependent inhibition of LPS (1 microg/mL)-induced release of NO and PGE(2), and a significant decrease in the transcription of proinflammatory cytokines. TRF at 1.0 microg/mL significantly blocked the LPS induction of iNOS and COX-2 expression, but not COX-1. This anti-inflammatory activity was further supported by the inhibition of NF-kappaB expression. These results conclude that TRF possesses potent anti-inflammatory activity, and its mechanism of action could be through the inhibition of iNOS and COX-2 production, as well as NF-kappaB expression.
Publication
Journal: Current Pharmaceutical Design
August/11/1999
Abstract
In cancer treatment, one of the approaches is targeting of the drug to tumor cells via receptor specific ligands. Transferrin (molecular weight 80,000) has been used as a ligand for delivering anticancer drugs or drug containing liposomes mostly due to the increased number of transferrin (trf) receptors found on tumor cells as compared to normal cells. Transferrin was linked to methotrexate (MTX) containing small unilamellar liposomes and its activity was compared to antitransferrin receptor antibody (7D-3) linked to MTX liposomes. In each of these conjugates, the method of coupling was the same and a disulphide linkage was formed between the ligand and MTX liposomes. No significant differences in the potency of 7D-3 conjugate or trf conjugate with MTX liposomes were observed in studies performed in vitro against various human tumor cell lines (Hela, KB and Colon). Trf was also linked to adriamycin via a schiff base which was formed by using glutaraldehyde. This conjugate was found to be effective in vitro against various human tumors (Lovo, HL-60, SW 403 and Hep2) and also in vivo against H-mesothelioma tumors. Transferrin receptor has also been used for gene delivery. Gene delivery to K562 haematopoietic leukaemic cells was achieved by using a transferrin-polycation (poly-L-lysine or protamine) conjugate. This review will cover the various important applications of transferrin based drug delivery formulations in the chemotherapy of cancer and the related work performed in our and other laboratories.
Authors
Publication
Journal: Atherosclerosis
January/2/2013
Abstract
OBJECTIVE
Multiple studies have identified single-nucleotide polymorphisms (SNPs) that are associated with coronary heart disease (CHD). We examined whether SNPs selected based on predefined criteria will improve CHD risk prediction when added to traditional risk factors (TRFs).
METHODS
SNPs were selected from the literature based on association with CHD, lack of association with a known CHD risk factor, and successful replication. A genetic risk score (GRS) was constructed based on these SNPs. Cox proportional hazards model was used to calculate CHD risk based on the Atherosclerosis Risk in Communities (ARIC) and Framingham CHD risk scores with and without the GRS.
RESULTS
The GRS was associated with risk for CHD (hazard ratio [HR] = 1.10; 95% confidence interval [CI]: 1.07-1.13). Addition of the GRS to the ARIC risk score significantly improved discrimination, reclassification, and calibration beyond that afforded by TRFs alone in non-Hispanic whites in the ARIC study. The area under the receiver operating characteristic curve (AUC) increased from 0.742 to 0.749 (Δ = 0.007; 95% CI, 0.004-0.013), and the net reclassification index (NRI) was 6.3%. Although the risk estimates for CHD in the Framingham Offspring (HR = 1.12; 95% CI: 1.10-1.14) and Rotterdam (HR = 1.08; 95% CI: 1.02-1.14) Studies were significantly improved by adding the GRS to TRFs, improvements in AUC and NRI were modest.
CONCLUSIONS
Addition of a GRS based on direct associations with CHD to TRFs significantly improved discrimination and reclassification in white participants of the ARIC Study, with no significant improvement in the Rotterdam and Framingham Offspring Studies.
Publication
Journal: Journal of Immunology
June/26/1980
Publication
Journal: Clinical Cancer Research
October/2/2003
Abstract
OBJECTIVE
It has been suggested that atypical adenomatous hyperplasia (AAH) may be a precursor of peripheral adenocarcinoma of the lung. Telomerase is a ribonucleoprotein enzyme that synthesizes telomeric DNA onto chromosomal ends. Its activity is thought to participate in the development of most human cancers. Telomere-specific DNA-binding proteins, such as telomeric repeat binding factor 1 and telomeric repeat binding factor 2, also control telomere length in a complex interplay with telomerase. Here we investigated the expressions of the mRNAs encoded by the TERF1 and TERF2 genes using in situ hybridization in surgically resected specimens [28 AAHs (11 lesions were interpreted as low-grade AAH, and 17 were interpreted as high-grade AAH) and 40 peripherally located bronchioloalveolar carcinoma (BAC).
RESULTS
A clear overexpression of these mRNAs was recognized in low- and high-grade AAH and BAC samples (as compared with normal tissues) using in situ hybridization and these mRNAs were detected in normal AAH and BAC samples using reverse transcription-PCR. The expressions of TERF1 and TERF2 mRNA detected by in situ hybridization were scored positive in 36% and 82% of low-grade AAH, 65% and 83% of high-grade AAH, and 88% and 88% of BAC, respectively. Statistically significant differences in TERF1 mRNA expression could be shown between low-grade AAH and BAC and between high-grade AAH and BAC. There was no statistical difference in the positive expressions of TERF2 mRNA among low-grade AAH, high-grade AAH, and BAC.
CONCLUSIONS
These results are consistent with (but are not enough to confirm) the idea that high-grade AAH is closely related to BAC.
Publication
Journal: Gastroenterology
July/23/2007
Abstract
OBJECTIVE
Selective removal of activated pancreatic stellate cells (PSCs) through induction of their own programmed death is a goal of therapeutic interest in patients with chronic pancreatitis. Here, we investigated the effects of tocotrienols on PSC death outcomes.
METHODS
Activated and quiescent PSCs and acinar cells from rat pancreas were treated with vitamin E derivatives alpha-tocopherol; individual alpha-, beta-, gamma-, and delta-tocotrienols; and a tocotrienol rich fraction (TRF) from palm oil.
RESULTS
TRF, but not alpha-tocopherol, reduced viability of activated PSC by setting up a full death program, independent of cell cycle regulation. Activated PSCs died both through apoptosis, as indicated by increased DNA fragmentation and caspase activation, and through autophagy, as denoted by the formation of autophagic vacuoles and LC3-II accumulation. In contrast to alpha-tocopherol, TRF caused an intense and sustained mitochondrial membrane depolarization and extensive cytochrome c release. Caspase inhibition with zVAD-fmk suppressed TRF-induced apoptosis but enhanced autophagy. However, mitochondrial permeability transition pore blockade with cyclosporin A completely abolished the deadly effects of TRF. beta-, gamma-, and delta-tocotrienol, but not alpha-tocotrienol nor alpha-tocopherol, reproduced TRF actions on activated PSCs. TRF death induction was restricted to activated PSCs because it did not cause apoptosis either in quiescent PSCs or in acinar cells.
CONCLUSIONS
Tocotrienols selectively trigger activated pancreatic stellate cell death by targeting the mitochondrial permeability transition pore. Our findings unveil a novel potential for tocotrienols to ameliorate the fibrogenesis associated with chronic pancreatitis.
Publication
Journal: Proteomics - Clinical Applications
June/2/2011
Abstract
OBJECTIVE
Glycosylation of acute-phase proteins (APP), which is partially regulated by cytokines, may be distinct in disease and provide useful tumour markers. Thus, we have examined the glycosylation of major serum APP in pancreatic cancer (PaC), chronic pancreatitis (CP) and control patients.
METHODS
Using a specific anti-sialyl Lewis X antibody and N-glycan sequencing, we have determined glycosylation changes on α-1-acid glycoprotein (AGP), haptoglobin (HPT), fetuin (FET), α-1-antitrypsin (AT) and transferrin (TRF).
RESULTS
Increased levels of sialyl Lewis X (SLe(x) ) were detected on AGP in advanced PaC and CP and on HPT, FET, AT and TRF in CP. An increase in N-glycan branching was detected on AGP and HPT in the advanced stage of PaC and CP and on FET and TRF in the CP. A core fucosylated structure was increased on AGP and HPT only in the advanced PaC patients.
CONCLUSIONS
Changes in APP SLe(x) and branching are probably associated with an inflammatory response because they were detected in both advanced PaC and CP patients and these conditions give rise to inflammation. On the contrary, the increase in APP core fucosylation could be cancer associated and the presence of this glycoform may give an advantage to the tumour.
Publication
Journal: Oncogene
August/18/1999
Abstract
Loss of telomeric repeats during cell proliferation could play a role in senescence. It has been generally assumed that activation of telomerase prevents further telomere shortening and is essential for cell immortalization. In this study, we performed a detailed cytogenetic and molecular characterization of four SV40 transformed human fibroblastic cell lines by regularly monitoring the size distribution of terminal restriction fragments, telomerase activity and the associated chromosomal instability throughout immortalization. The mean TRF lengths progressively decreased in pre-crisis cells during the lifespan of the cultures. At crisis, telomeres reached a critical size, different among the cell lines, contributing to the peak of dicentric chromosomes, which resulted mostly from telomeric associations. We observed a direct correlation between short telomere length at crisis and chromosomal instability. In two immortal cell lines, although telomerase was detected, mean telomere length still continued to decrease whereas the number of dicentric chromosomes associated was stabilized. Thus telomerase could protect specifically telomeres which have reached a critical size against end-to-end dicentrics, while long telomeres continue to decrease, although at a slower rate as before crisis. This suggests a balance between elongation by telomerase and telomere shortening, towards a stabilized 'optimal' length.
Publication
Journal: Frontiers in Microbiology
April/22/2015
Abstract
Microorganisms associated with medicinal plants are of interest as the producers of important bioactive compounds. To date, the diversity of culturable endophytic actinomycetes associated with medicinal plants is in its initial phase of exploration. In this study, 42 endophytic actinomycetes were isolated from different organs of seven selected medicinal plants. The highest number of isolates (n = 22, 52.3%) of actinomycetes was isolated from roots, followed by stems (n = 9, 21.4%), leaves (n = 6, 14.2%), flowers (n = 3, 7.1%), and petioles (n = 2, 4.7%). The genus Streptomyces was the most dominant among the isolates (66.6%) in both the locations (Dampa TRF and Phawngpuii NP, Mizoram, India). From a total of 42 isolates, 22 isolates were selected for further studies based on their ability to inhibit one of the tested human bacterial or fungal pathogen. Selected isolates were identified based on 16S rRNA gene analysis and subsequently the isolates were grouped to four different genera; Streptomyces, Brevibacterium, Microbacterium, and Leifsonia. Antibiotic sensitivity assay was performed to understand the responsible antimicrobials present in the isolates showing the antimicrobial activities and revealed that the isolates were mostly resistant to penicillin G and ampicillin. Further, antimicrobial properties and antibiotic sensitivity assay in combination with the results of amplification of biosynthetic genes polyketide synthase (PKS-I) and non-ribosomal peptide synthetase (NRPS) showed that the endophytic actinomycetes associated with the selected medicinal plants have broad-spectrum antimicrobial activity. This is the first report of the isolation of Brevibacterium sp., Microbacterium sp., and Leifsonia xyli from endophytic environments of medicinal plants, Mirabilis jalapa and Clerodendrum colebrookianum. Our results emphasize that endophytic actinomycetes associated with medicinal plants are an unexplored resource for the discovery of biologically active compounds.
Publication
Journal: Heart
April/6/2008
Abstract
BACKGROUND
Telomeres are shorter in subjects with coronary artery disease (CAD) and may indicate premature biological ageing. However, whether shorter telomeres are a primary abnormality or secondary to the disease is unclear.
OBJECTIVE
To investigate whether shorter telomeres are a primary abnormality or secondary to CAD, telomere lengths in healthy young adults with contrasting familial risk of CAD were compared.
METHODS
Case-control study.
METHODS
Mean telomere restriction fragment (TRF) length in DNA from circulating leucocytes was determined by Southern blotting in 45 healthy offspring of subjects with premature CAD (case offspring) and 59 offspring from families without such a history (control offspring). Correlation in mean TRF length was also assessed in 67 offspring-parent pairs.
RESULTS
On average, a decrease of 27.5 (10.7) bp in mean TRF per year of age was found. The unadjusted mean TRF length was 6.34 kb (95% CI 6.13 to 6.55) for case offspring and 6.75 kb (95% CI 6.57 to 6.94) for offspring of controls (p = 0.004). The adjusted difference in mean TRF between case and control offspring was 472 bp (95% CI 253 to 691, p<0.001), equivalent to about 17 years of age-related attrition in telomere length. Furthermore, there was a significant positive correlation in mean TRF length between offspring and their parents (r = 0.37, p = 0.002).
CONCLUSIONS
These findings suggest that inheritance of shorter telomeres is associated with increased familial risk of CAD. They support the hypothesis that telomere length is a primary abnormality involved in the pathogenesis of CAD.
Publication
Journal: Applied and Environmental Microbiology
May/2/2005
Abstract
TRF-CUT, an ARB-implemented tool, was developed to predict in silico the terminal restriction fragments of aligned small-subunit rRNA gene or functional gene sequences. Application of this new tool to perform directed terminal restriction fragment length polymorphism analysis of pmoA products obtained from a forest soil revealed that novel cluster I methanotrophic bacteria were dominant.
Publication
Journal: Neuroscience Letters
March/20/1996
Abstract
The tocotrienol-rich-fraction (TRF) from palm oil, being tried as a more economical and efficient substitute for alpha-tocopherol, significantly inhibited oxidative damage in vitro to both lipids and proteins in rat brain mitochondria induced by ascorbate-Fe2+, the free radical initiator azobis(2-amidopropane)dihydrochloride (AAPH) and photosensitisation. The observed inhibitory effect was both time- and concentration-dependent. At a low concentration of 5 microM, TRF can significantly inhibit oxidative damage to both lipids and proteins. The inhibitory effect of TRF seems to be mainly due to gamma-tocotrienol and to a lesser extent alpha- and delta-tocotrienols. TRF was significantly more effective than alpha-tocopherol. This fraction from palm oil can be considered a natural antioxidant supplement capable of protecting the brain against oxidative damage and thereby from the ensuing adverse alterations.
Publication
Journal: Journal of Immunology
June/19/1985
Abstract
Experiments were performed to examine a growth-promoting activity on B cells or B leukemic cells of T cell-replacing factor (TRF) produced by a murine T cell hybridoma (B151K12) which constitutively produces TRF. The cellfree supernatant (CFS) from B151K12 cells (B151-CFS) could induce terminal differentiation of pre-activated B cells or in vivo passaged chronic B leukemia cells, BCL1, into immunoglobulin-secreting cells, while it did not exert a nominal lymphokine activity such as BCGFI (now known as BSFpl), IL 2, or gamma-interferon. However, it promoted [3H]thymidine uptake of dextran sulfate (DXS)-stimulated normal B cells and in vivo passaged BCL1 cells, suggesting that it also has BCGFII activity. We tried extensively to purify and to separate the TRF active molecule from the BCGFII active molecule by using many types of purification procedures. The purification scheme consisted of ammonium sulfate precipitation, DEAE-cellulose chromatography, Blue-Sepharose chromatography, hydroxylapatite chromatography, and gel permeation with fast protein liquid chromatography (FPLC). It was revealed that the BCGFII active molecule was hardly separable from the TRF during the entire purification procedure. The TRF as well as BCGFII active materials were glycoprotein with an apparent m.w. of 50 to 60 Kd on gel permeation chromatography and 18 Kd on SDS-PAGE under reducing conditions. The BCGFII active materials were hardly separable from the TRF active one, even after a reverse-phase FPLC, in which both BCGFII and TRF activities were recovered in the fractions eluted at 44 to 48% acetonitrile in 0.1% trifluoroacetic acid (TFA). Furthermore, the absorption of TRF and BCGFII active materials by using BCL1 cells removed not only TRF but also BCGFII activity. Moreover, B cell-specific monoclonal antibody (9T1), which can preferentially block TRF-dependent plaque-forming cell responses, also inhibited the expression of BCGFII activity to BCL1 cells. Taking all of the results together, we conclude that the TRF from B151K12 cells promotes growth of appropriately activated, such as DXS-stimulated normal cells and BCL1 tumor cells. These results suggest that B151-TRF may act on B cells as B cell growth and differentiation factors.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
January/22/2004
Abstract
TATA-box-binding protein (TBP) is a highly conserved RNA polymerase II general transcription factor that binds to the core promoter and initiates assembly of the preinitiation complex. Two proteins with high homology to TBP have been found: TBP-related factor 1 (TRFTRFTRFTRFTRFTRFTRFTRFTRFTRFTRF whose phylogenetic conservation, expression pattern, and other properties are distinct from those of TBP and all other TRFs.
Publication
Journal: World Journal of Surgery
November/29/2006
Abstract
OBJECTIVE
The purpose of this study was to evaluate the effect of preoperative immunonutrition pharmaceutics (IMPACT) diet versus standard enteral nutrition (EN) on the nutritional status and immunity of patients with colorectal or gastrointestinal (GI) cancer and to evaluate whether it influences the incidence of postoperative complication.
METHODS
Sixty patients with GI cancer were randomly divided into 2 groups, immunonutrition (IM) and control diet (CT), each of which was fed with IMPACT and conventional diet, respectively, for 7 days before surgical procedures. Variables of nutritional status and immunity, postoperative complications, infections, and the days of postoperative hospitalization were measured.
RESULTS
There were no significant differences in the immunological and nutritional variables between the 2 groups preoperatively. The incidence of postoperative complications was significantly lower and the days of postoperative hospitalization were significantly decreased in the IM group. Serum concentrations of both prealbumin (PALB) and transferrin (TRF) were lower in the IM than in the CT group on postoperative day 3 (P<0.01). TRF continued to be significantly lower in the CT group than in the IM group between day 4 and day 7. However, PALB was significantly lower than before operation in the IM group on postoperative day 3 and TRF was significantly higher in the IM than the CT group on postoperative day 3 (P<0.05). Both PALB and TRF were significantly higher in the IM than the CT group on postoperative day 7 (P<0.05). Postoperative immunoglobulin G (IgG) level in the IM group was higher than that in the CT group (13.35+/-2.06 g/l vs. 9.59+/-2.23 g/l, P<0.05). CD4/CD8 ratio was significantly higher in the IM group (2.10+/-0.51 vs. 1.62+/-0.52, P<0.05).
CONCLUSIONS
Preoperative enteral IM in patients with GI cancer improves nutritional status and immunity and decreases the incidence of postoperative complications and infections.
Publication
Journal: Cancer Letters
March/25/2019
Abstract
tRNA-derived fragments (tRFs) and tRNA halves (tiRNAs) are small non-coding RNAs derived from precursor tRNAs or mature tRNAs. Depending on the sources, tRFs can be divided into tRF-1, tRF-2, tRF-3, tRF-5, and i-tRF; tiRNAs can be divided into 5'tiRNA and 3'tiRNA. Both tRFs and tiRNAs play important roles in tumorigenesis. Some tRFs and tiRNAs promote cell proliferation and cell cycle progression by regulating the expression of oncogenes. Other tRFs and tiRNAs inhibit cancer progression. Mechanism studies have shown that tRFs and tiRNAs may bind to RNA binding proteins such as Y-box binding protein 1 (YBX1) and prevent transcription, inactivate initiation factor eIF4G/A, promote translation of ribosomal proteins, or activate aurora kinase A, the regulator of mitosis. Therefore, tRFs and tiRNAs regulate the occurrence and development of cancers, including lung cancer, colorectal cancer, prostate cancer, breast cancer, ovarian cancer, B cell lymphoma, chronic lymphocytic leukemia, etc. This article reviews the classification of tRFs and tiRNAs, their biological functions in the occurrence of cancers, and their relationships with some common cancers. It will provide new ideas for the diagnosis and treatment of cancers.
Publication
Journal: European Psychiatry
September/13/2009
Abstract
OBJECTIVE
The purpose of this study was to investigate the degree of agreement among parents, teachers and adolescents with respect to the Child Behavior Checklist (CBCL), the Teacher's Report Form (TRF), and the Youth Self Report (YSR). In addition we evaluated the suitability of these three forms (CBCL, TRF and YSR) in terms of their contribution to understanding internalizing and externalizing disorders in youths being referred to a child and adolescent unit of a psychiatric care facility.
METHODS
A total of 611 patients aged 11-18 years (mean age 13.0, SD 1.6) were assessed using the CBCL, the TRF and the YSR.
RESULTS
Intraclass coefficients (ICC) showed low to moderate agreement among informants. Furthermore, the level of agreement was generally less among patients suffering from internalizing disorders than for young patients who displayed externalizing disorders. Logistic regression revealed that the TRF internalizing syndrome scale, the CBCL internalizing syndrome scale and gender were relevant prognostic factors for the occurrence of internalizing disorders in youth. The YSR internalizing syndrome scale, on the other hand, was not a relevant factor among adolescents of a clinical target population. Likewise, only the TRF externalizing syndrome scale, the CBCL externalizing syndrome scale and gender were relevant prognostic factors for the occurrence of externalizing disorders in youth.
CONCLUSIONS
Particularly the CBCL and TRF are useful instruments in assessing internalizing and externalizing disorders in adolescents referred to a mental health setting.
Publication
Journal: Journal of Virology
May/3/2010
Abstract
Poly(ADP-ribose) polymerase (PARP) is an abundant, chromatin-associated, NAD-dependent enzyme that functions in multiple chromosomal processes, including DNA replication and chromatin remodeling. The Epstein-Barr virus (EBV) origin of plasmid replication (OriP) is a dynamic genetic element that confers stable episome maintenance, DNA replication initiation, and chromatin organization functions. OriP function depends on the EBV-encoded origin binding protein EBNA1. We have previously shown that EBNA1 is subject to negative regulation by poly(ADP-ribosyl)ation (PARylation). We now show that PARP1 physically associates with OriP in latently EBV-infected B cells. Short hairpin RNA depletion of PARP1 enhances OriP replication activity and increases EBNA1, origin recognition complex 2 (ORC2), and minichromosome maintenance complex (MCM) association with OriP. Pharmacological inhibitors of PARP1 enhance OriP plasmid maintenance and increase EBNA1, ORC2, and MCM3 occupancy at OriP. PARylation in vitro inhibits ORC2 recruitment and remodels telomere repeat factor (<em>TRF</em>) binding at the dyad symmetry (DS) element of OriP. Purified PARP1 can ribosylate EBNA1 at multiple sites throughout its amino terminus but not in the carboxy-terminal DNA binding domain. We also show that EBNA1 linking regions (LR1 and LR2) can bind directly to oligomers of PAR. We propose that PARP1-dependent PARylation of EBNA1 and adjacently bound <em>TRF</em>2 induces structural changes at the DS element that reduce EBNA1 DNA binding affinity and functional recruitment of ORC.
Publication
Journal: Nutrients
June/1/2019
Abstract
Time-restricted feeding (TRF) is a form of intermittent fasting that involves having a longer daily fasting period. Preliminary studies report that TRF improves cardiometabolic health in rodents and humans. Here, we performed the first study to determine how TRF affects gene expression, circulating hormones, and diurnal patterns in cardiometabolic risk factors in humans. Eleven overweight adults participated in a 4-day randomized crossover study where they ate between 8 am and 2 pm (early TRF (eTRF)) and between 8 am and 8 pm (control schedule). Participants underwent continuous glucose monitoring, and blood was drawn to assess cardiometabolic risk factors, hormones, and gene expression in whole blood cells. Relative to the control schedule, eTRF decreased mean 24-hour glucose levels by 4 ± 1 mg/dl (p = 0.0003) and glycemic excursions by 12 ± 3 mg/dl (p = 0.001). In the morning before breakfast, eTRF increased ketones, cholesterol, and the expression of the stress response and aging gene SIRT1 and the autophagy gene LC3A (all p < 0.04), while in the evening, it tended to increase brain-derived neurotropic factor (BNDF; p = 0.10) and also increased the expression of MTOR (p = 0.007), a major nutrient-sensing protein that regulates cell growth. eTRF also altered the diurnal patterns in cortisol and the expression of several circadian clock genes (p < 0.05). eTRF improves 24-hour glucose levels, alters lipid metabolism and circadian clock gene expression, and may also increase autophagy and have anti-aging effects in humans.
Publication
Journal: American Journal of Human Genetics
June/20/1982
Abstract
Conserved linkage groups have been found on the X and autosomal chromosomes in several mammalian species. The identification of conserved chromosomal regions has potential for predicting gene location in mammals, particularly in humans. The genes for human aminoacylase-1 (ACY1, N-acylamino acid aminohydrolase, E.C.3.5.1.14), an enzyme in amino acid metabolism, and beta-galactosidase-A (GLB1, E.C.3.2.1.23), deficient in GM1-gangliosidosis, have been assigned to human chromosome 3. Using human-mouse somatic cell hybrids segregating translocations of human chromosome 3, expression of both ACY1 and GLB1 correlated with the presence of the p21 leads to q21 region of chromosome 3. In a previous study, assignment of these genes to mouse chromosome 9 used mouse-Chinese hamster somatic cell hybrids, eliminating mouse chromosomes. To approximate the size of the conserved region in the mouse, experiments were performed with recombinant inbred mouse strains. An electrophoretic variant of ACY-1 in mouse strains was used to map the Acy-1 gene 10.7 map U from the beta-galactosidase locus. These data suggest that there is a region of homology within the p21 leads to q21 region of human chromosome 3 and a segment of mouse chromosome 9. Since the mouse transferrin gene (Trf) is closely linked to the aminoacylase and beta-galactosidase loci, we predict that the human transferrin (TF) gene is on chromosome 3.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/31/1976
Abstract
TSH, PRL and GH response to TSH releasing factor as well as basal T4 and T3 were evaluated in a group of patients with chronic renal failure undergoing chronic hemodialysis. Serum T4 and T3 were lower than normal. Basal TSH was normal as compared to control, but did not rise after TRF stimulation. Larger dosages of TRF did not correct this abnormal response. Basal PRL was higher than control and remained at the same level during the test. GH was stimulated by the TRF with a peak occurring 20 min after injection. This abnormal secretion was not blunted by T3 administration. TRF half-life measured in 3 patients was 4 min. These data indicate that 1) there is an abnormal response to TRF in chronic renal failure which does not seem to be due to an altered sensitivity to, or metabolism of TRF; and 2) there is an abnormal TSH secretion which may be responsible for the low T4 and T3 measured in these patients.
Publication
Journal: Journal of Nutritional Biochemistry
August/21/2001
Abstract
Tocotrienols exert hypocholesterolemic action in humans and animals. Lovastatin is widely used for that purpose. Both agents work by suppressing the activity of beta-hydroxy-beta-methylglutaryl coenzyme A reductase through different mechanisms, post-transcriptional vs competitive inhibition. A human study with 28 hypercholesterolemic subjects was carried out in 5 phases of 35 days each, to check the efficacy of tocotrienol-rich fraction (TRF(25)) of rice bran alone and in combination with lovastatin. After placing subjects on the American Heart Association (AHA) Step-1 diet (phase II), the subjects were divided into two groups, A and B. The AHA Step-1 diet was continued in combination with other treatments during phases III to V. Group A subjects were given 10 mg lovastatin, 10 mg lovastatin plus 50 mg TRF(25), 10 mg lovastatin plus 50 mg alpha-tocopherol per day, in the third, fourth, and fifth phases, respectively. Group B subjects were treated exactly to the same protocol except that in the third phase, they were given 50 mg TRF(25) instead of lovastatin.The TRF(25) or lovastatin plus AHA Step-1 diet effectively lower serum total cholesterol (14%, 13%) and LDL-cholesterol (18%, 15% P < 0.001), respectively, in hypercholesterolemic subjects. The combination of TRF(25) and lovastatin plus AHA Step-1 diet significantly reduces of these lipid parameters of 20% and 25% (P < 0.001) in these subjects. Substitution of TRF(25) with alpha-tocopherol produces insignificant changes when given with lovastatin. Especially significant is the increase in the HDL/LDL ratio to 46% in group (A) and 53% (P < 0.002) in group (B). These results are consistent with the synergistic effect of these two agents. None of the subjects reported any side-effects throughout the study of 25-weeks. In the present study, the increased effectiveness of low doses of tocotrienols (TRF(25)) as hypocholesterolemic agents might be due to a minimum conversion to alpha-tocopherol. The report also describes in vivo the conversion of gamma-[4-3H]-, and [14C]-desmethyl (d-P(21)-T3) tocotrienols to alpha-tocopherol.
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