Protection against diethylnitrosoamine-induced hepatocarcinogenesis by an indigenous medicine comprised of Nigella sativa, Hemidesmus indicus and Smilax glabra: a preliminary study

BACKGROUND: A decoction comprised of Nigella sativa seeds, Hemidesmus indicus root and Smilax glabra rhizome is used to treat cancer patients in Sri Lanka. However, the anti-carcinogenic properties of this decoction have not been experimentally confirmed. The purpose of this study was to determine whether the above decoction could protect against chemically induce hepatocarcinogenesis. METHODS: The effects of this decoction on diethylnitrosamine (DEN) induced hepatocarcinogenesis were examined in male Wistar rats using the medium term bioassay system of Ito, based on a 2-step model of hepatocarcinogenesis. Rats were randomly divided into 6 groups of 10 each. Groups 1 to 4 were injected with DEN (200 mg/kg) to initiate carcinogenesis. Twenty-four hours later groups 1 and 2 were administered the decoction at 4 g/kg body weight/day (dose 1) and 6 g/kg body weight/day (dose 2), respectively. Group 3 and group 4 were given distilled water instead of the decoction and a suspension of garlic powder (20 g/kg body weight/day) in distilled water (positive control), respectively. Group 5 and 6 were injected with normal saline and twenty-four hours later group 5 was given distilled water (normal control) while group 6 was given decoction dose 2 (decoction control). Oral feeding continued for two weeks after which all rats were subjected to 2/3 partial hepatectomy to promote carcinogenesis. Oral feeding continued for eight more weeks. At the end of the 10th week, rats were sacrificed and samples of livers taken for immunohistochemical studies.Carcinogenic potential was scored by comparing the number, area and staining intensity of glutathione S-transferase placental form (GST-P) positive foci and the number of cells/cm2 of the positive foci in the livers of the six groups of rats. RESULTS: The number and area of DEN-mediated GST-P positive foci, number of cells/cm2 of foci and staining intensity of the foci were significantly (P > 0.001) reduced by the decoction and garlic in the order dose 2 = garlic >dose 1. CONCLUSION: Overall results indicate that the decoction comprised of N. sativa, S. glabra and H. indicus has the potential to protect rat liver against DEN induced hepatocarcinogenesis     

Cathepsin B promotes both motility and invasiveness of oral carcinoma cells

We previously demonstrated that overexpression of cathepsin B (CB) protease in oral squamous cell carcinomas correlated positively with advanced tumor stage and poor histologic malignancy grade. Here we examined whether CB contributes to the invasiveness of oral carcinoma cells. For RNA-mediated inhibition, two ribozymes that target CB mRNA were designed and stably expressed in the oral squamous cell carcinoma cell line 1386Tu. Both ribozymes diminished expression of CB mRNA, protein, and activity, without affecting cathepsin D or beta-actin, as determined by quantitative real-time PCR, Western blots, and protease activity assays. Matrigel invasion assays showed that the invasiveness of the cells was significantly reduced by the expressed ribozymes and, surprisingly, the motilities of the ribozyme-transfected cells were also diminished. Our results document a direct role for CB in promoting oral cancer spread and invasion, and open the possibility of controlling oral carcinoma malignancy and metastasis by targeting CB with RNA inhibitor strategies.     

Estradiol downregulates miR-21 expression and increases miR-21 target gene expression in MCF-7 breast cancer cells

Select changes in microRNA (miRNA) expression correlate with estrogen receptor α (ERα) expression in breast tumors. miR-21 is higher in ERα positive than negative tumors, but no one has examined how estradiol (E₂) regulates miR-21 in breast cancer cells. Here we report that E₂ inhibits miR-21 expression in MCF-7 human breast cancer cells. The E₂-induced reduction in miR-21 was inhibited by 4-hydroxytamoxifen (4-OHT), ICI 182 780 (Faslodex), and siRNA ERα indicating that the suppression is ERα-mediated. ERα and ERβ agonists PPT and DPN inhibited and 4-OHT increased miR-21 expression. E₂ increased luciferase activity from reporters containing the miR-21 recognition elements from the 3′-UTRs of miR-21 target genes, corroborating that E₂ represses miR-21 expression resulting in a loss of target gene suppression. The E₂-mediated decrease in miR-21 correlated with increased protein expression of endogenous miR-21-targets Pdcd4, PTEN and Bcl-2. siRNA knockdown of ERα blocked the E₂-induced increase in Pdcd4, PTEN and Bcl-2. Transfection of MCF-7 cells with antisense (AS) to miR-21 mimicked the E₂-induced increase in Pdcd4, PTEN and Bcl-2. These results are the first to demonstrate that E₂ represses the expression of an oncogenic miRNA, miR-21, by activating estrogen receptor in MCF-7 cells.     

Lipid peroxidation product 4-hydroxy-trans-2-nonenal causes endothelial activation by inducing endoplasmic reticulum stress

Lipid peroxidation products, such as 4-hydroxy-trans-2-nonenal (HNE), cause endothelial activation, and they increase the adhesion of the endothelium to circulating leukocytes. Nevertheless, the mechanisms underlying these effects remain unclear. We observed that in HNE-treated human umbilical vein endothelial cells, some of the protein-HNE adducts colocalize with the endoplasmic reticulum (ER) and that HNE forms covalent adducts with several ER chaperones that assist in protein folding. We also found that at concentrations that did not induce apoptosis or necrosis, HNE activated the unfolded protein response, leading to an increase in XBP-1 splicing, phosphorylation of protein kinase-like ER kinase and eukaryotic translation initiation factor 2α, and the induction of ATF3 and ATF4. This increase in eukaryotic translation initiation factor 2α phosphorylation was prevented by transfection with protein kinase-like ER kinase siRNA. Treatment with HNE increased the expression of the ER chaperones, GRP78 and HERP. Exposure to HNE led to a depletion of reduced glutathione and an increase in the production of reactive oxygen species (ROS); however, glutathione depletion and ROS production by tert-butyl-hydroperoxide did not trigger the unfolded protein response. Pretreatment with a chemical chaperone, phenylbutyric acid, or adenoviral transfection with ATF6 attenuated HNE-induced monocyte adhesion and IL-8 induction. Moreover, phenylbutyric acid and taurine-conjugated ursodeoxycholic acid attenuated HNE-induced leukocyte rolling and their firm adhesion to the endothelium in rat cremaster muscle. These data suggest that endothelial activation by HNE is mediated in part by ER stress, induced by mechanisms independent of ROS production or glutathione depletion. The induction of ER stress may be a significant cause of vascular inflammation induced by products of oxidized lipids.     

Testing approaches to sharing trial results with participants: The Show RESPECT cluster randomised,factorial, mixed methods trial

BackgroundSharing trial results with participants is an ethical imperative but often does not happen. We tested an Enhanced Webpage versus a Basic Webpage, Mailed Printed Summary versus no Mailed Printed Summary, and Email List Invitation versus no Email List Invitation to see which approach resulted in the highest patient satisfaction with how the results were communicated.Methods and findingsWe carried out a cluster randomised, 2 by 2 by 2 factorial, nonblinded study within a trial, with semistructured qualitative interviews with some patients (ISRCTN96189403). Each cluster was a UK hospital participating in the ICON8 ovarian cancer trial. Interventions were shared with 384 ICON8 participants who were alive and considered well enough to be contacted, at 43 hospitals. Hospitals were allocated to share results with participants through one of the 8 intervention combinations based on random permutation within blocks of 8, stratified by number of participants. All interventions contained a written plain English summary of the results. The Enhanced Webpage also contained a short video. Both the Enhanced Webpage and Email contained links to further information and support. The Mailed Printed Summary was opt-out.Follow-up questionnaires were sent 1 month after patients had been offered the interventions. Patients’ reported satisfaction was measured using a 5-point scale, analysed by ordinal logistic regression estimating main effects for all 3 interventions, with random effects for site, restricted to those who reported receiving the results and assuming no interaction. Data collection took place in 2018 to 2019.Questionnaires were sent to 275/384 randomly selected participants and returned by 180: 90/142 allocated Basic Webpage, 90/133 Enhanced Webpage; 91/141 no Mailed Printed Summary, 89/134 Mailed Printed Summary; 82/129 no Email List Invitation, 98/146 Email List Invitation. Only 3 patients opted out of receiving the Mailed Printed Summary; no patients signed up to the email list. Patients’ satisfaction was greater at sites allocated the Mailed Printed Summary, where 65/81 (80%) were quite or very satisfied compared to sites with no Mailed Printed Summary 39/64 (61%), ordinal odds ratio (OR) = 3.15 (1.66 to 5.98, p < 0.001). We found no effect on patient satisfaction from the Enhanced Webpage, OR = 1.47 (0.78 to 2.76, p = 0.235) or Email List Invitation, OR = 1.38 (0.72 to 2.63, p = 0.327). Interviewees described the results as interesting, important, and disappointing (the ICON8 trial found no benefit). Finding out the results made some feel their trial participation had been more worthwhile. Regardless of allocated group, patients who received results generally reported that the information was easy to understand and find, were glad and did not regret finding out the results. The main limitation of our study is the 65% response rate.ConclusionsNearly all respondents wanted to know the results and were glad to receive them. Adding an opt-out Mailed Printed Summary alongside a webpage yielded the highest reported satisfaction. This study provides evidence on how to share results with other similar trial populations. Further research is needed to look at different results scenarios and patient populations.Trial registrationISRCTN: ISRCTN96189403.

In this mixed methods trial, Annabelle South and colleagues investigate different approaches to sharing the results of a clinical trial with its participants.     

Chemical esterification of 5′-AMP occurs predominantly at the 2′ position

We describe experiments here which show that chemical esterification of 5'-adenylic acid (5'-AMP) with N-acetyl D- or L-phenylalanine (Ac-D- or Ac-L-Phe) imidazolide occurs principally, if not exclusively, at the 2' position. Furthermore, in experiments with the formation of the 2'-3' diester with butyric acid and N-acetyl glycine (Ac-Gly), we found the second esterification was also predominantly at the 2' position. This means that mixed diesters can be predictably prepared with the positions of the substituents known. The results are consistent with a model for the preferential catalytic synthesis of L-based peptides via a 2'-3' diester intermediate of purine monoribonucleotides.     

N-Acetyl-D and L-esters of 5′-AMP hydrolyze at different rates

Studies of the properties of aminoacyl derivatives of 5′-AMP are aimed at understanding the origin of the process of protein synthesis. Aminoacyl (2′,3′) esters of 5′-AMP can serve as models of the 3′-terminus of aminoacyl tRNA. We report here on the relative rates of hydrolysis of AC -D - and L -Phe AMP esters as a function of pH. At all pHs above 3, the rate constant of hydrolysis of the AC -L -Phe ester is 1.7 to 2.1 times that of AC -D -Phe ester. The D -isomer seems partially protected from hydrolysis by a stronger association with the adenine ring of the 5′-AMP. © 1993 Wiley-Liss, Inc.     

A cross-sectional study of pain sensitivity,disease-activity assessment,mental health,and fibromyalgia status in rheumatoid arthritis

IntroductionPain remains the most important problem for people with rheumatoid arthritis (RA). Active inflammatory disease contributes to pain, but pain due to non-inflammatory mechanisms can confound the assessment of disease activity. We hypothesize that augmented pain processing, fibromyalgic features, poorer mental health, and patient-reported 28-joint disease activity score (DAS28) components are associated in RA.MethodsIn total, 50 people with stable, long-standing RA recruited from a rheumatology outpatient clinic were assessed for pain-pressure thresholds (PPTs) at three separate sites (knee, tibia, and sternum), DAS28, fibromyalgia, and mental health status. Multivariable analysis was performed to assess the association between PPT and DAS28 components, DAS28-P (the proportion of DAS28 derived from the patient-reported components of visual analogue score and tender joint count), or fibromyalgia status.ResultsMore-sensitive PPTs at sites over or distant from joints were each associated with greater reported pain, higher patient-reported DAS28 components, and poorer mental health. A high proportion of participants (48%) satisfied classification criteria for fibromyalgia, and fibromyalgia classification or characteristics were each associated with more sensitive PPTs, higher patient-reported DAS28 components, and poorer mental health.ConclusionsWidespread sensitivity to pressure-induced pain, a high prevalence of fibromyalgic features, higher patient-reported DAS28 components, and poorer mental health are all linked in established RA. The increased sensitivity at nonjoint sites (sternum and anterior tibia), as well as over joints, indicates that central mechanisms may contribute to pain sensitivity in RA. The contribution of patient-reported components to high DAS28 should inform decisions on disease-modifying or pain-management approaches in the treatment of RA when inflammation may be well controlled.     

Hydrolytic properties of phenylalanyl- and N-acetylphenylalanyl adenylate anhydrides

We have used a novel spectrophotometric method to study the hydrolysis of N-acetylphenylalanyl adenylate anhydride (AcPhe-AMP) and phenylalanyl-adenylate anhydride (Phe-AMP) at low concentrations (10^–5 M), 25 °C, constant buffer concentration (0.05 M), and as a function of pH. While Phe-AMP is susceptible principally to attack by OH^–, with two different rates depending on whether the -amino group of the amino acid is protonated or not, the AcPhe-AMP is susceptible to acid decomposition as well. At pH's 4–8, the Phe-AMP hydrolyzes faster than the AcPhe-AMP, but at pH less than 4 or pH greater than 8, the blocked form hydrolyzes faster. Both forms are also attacked by H₂O, and at the same rate. Moreover, the hydrolysis of Phe-AMP is shown to be greatly catalyzed by carbonate, although the AcPhe-AMP is not subject to such catalysis. The rate laws for the various mechanisms and the activation energies for the hydrolyses at pH 7.1 are given.