Molecular mechanisms of myricetin bulk and nano forms mediating genoprotective and genotoxic effects in lymphocytes from pre-cancerous and myeloma patients

Cancer is one of the leading causes of death across the globe which needs appropriate and cost-effective treatment. Several recent studies have suggested that dietary intake of various flavonoids such as myricetin have a protective effect against different types of cancers and cardiovascular diseases. The present study was conducted to investigate the genoprotective and genotoxic effects of myricetin nano and bulk forms on the lymphocytes from pre-cancerous and multiple myeloma cancer patients compared to those from healthy individuals. Also, to investigate the protective potential of myricetin bulk and nano against the oxidative stress produced in vitro by 2- amino-1-methyl-6 phenylimidazo [4, 5-b] pyridine and reactive oxygen species- induced DNA damage using the Comet assay, micronucleus assay, cellular reactive oxygen species and glutathione detection assay, Western blotting, real-time polymerase chain reaction and immunofluorescence. Lymphocytes from the patient groups showed significantly higher levels of basal DNA damage compared to the lymphocytes from healthy individuals which was observed throughout the in vitro treatment. Myricetin in both forms has not induced any significant DNA damage in all of the investigative groups at selective lower concentrations; in fact, the results demonstrate a reduction in DNA damage upon treating with myricetin nano in lymphocytes from pre-cancerous patients demonstrated by significant reduction in micronuclei formation in mononucleated cells. DNA repair capacity of myricetin bulk and nano was determined by co-treating the drugs with hydrogen peroxide. Myricetin significantly reduced the oxidative stress related damage caused by hydrogen peroxide, where myricetin nano seemed to be more effective employing the Comet assay. In the presence of myricetin bulk and nano, the damaging effects of 2- amino-1-methyl-6 phenylimidazo [4,5-b] pyridine were considerably decreased, where myricetin nano was more effective. This could be because nanoparticles have a larger surface area which could improve their reactivity and also the reduction in size of the particles could improve the anti-cancer properties of this compound. Myricetin has shown genoprotective and anti-oxidant effects by demonstrating the potential to reduce DNA damage caused by over-production of reactive oxygen species and oxidative stress. It has also shown anti-cancer potential in the lymphocytes from multiple myeloma patients by regulating the apoptosis related proteins, dependent on oxidative stress. Therefore, this study suggests that myricetin supplementation in our regular diet with enhanced bioavailability could have potential health beneficial effects and possibly protect against various diseases including cancer

ROS-induced Oxidative Damage in Lymphocytes Ex Vivo/in Vitro From Healthy Individuals and MGUS Patients: Protection by Myricetin Bulk and Nanoforms

YesWe investigated the protective role of myricetin bulk and nanoforms, against reactive oxygen species (ROS)-induced oxidative stress caused by hydrogen peroxide and tertiary-butyl hydro peroxide in lymphocytes in vitro from healthy individuals and those from pre-cancerous patients suffering with monoclonal gammopathy of undetermined significance (MGUS). The change in intracellular reactive oxygen species was measured once cells were treated with myricetin bulk forms and nanoforms with and without either hydrogen peroxide or tertiary-butyl hydro peroxide co-supplementation. The direct and indirect antioxidant activity of myricetin was spectrofluometrically measured using the fluorescent dye 2',7'-dichlorofluorescin diacetate and using the Comet assay, respectively. Hydrogen peroxide (50 µM) and tertiary-butyl hydro peroxide (300 µM) induced a higher level of reactive oxygen species-related DNA damage and strand breaks. Addition of myricetin nanoform (20 µM) and bulk (10 µM) form could, however, significantly prevent hydrogen peroxide- and tertiary-butyl hydro peroxide-induced oxidative imbalances and the nanoform was more effective. Glutathione levels were also quantified using a non-fluorescent dye. Results suggest that myricetin treatment had no significant effect on the cellular antioxidant enzyme, glutathione. The current study also investigates the effect of myricetin on the induction of double-strand breaks by staining the gamma-H2AX foci immunocytochemically. It was observed that myricetin does not induce double-strand breaks at basal levels rather demonstrated a protective effect

A Review on Anticancer Potential of Nitric Oxide

Nitrous oxide (NO) is a free radical gas which performs various physiological and pathological processes in body. NO is produced by different enzymatic pathways and plays role in homeostasis. Over past years, NO has emerged as a molecule of interest in many ailments including cancer. But its role in cancer is still controversy. It can display dose-dependant anticancer therapy on one hand and induce procancer properties on the other hand. But as compared to conventional treatments, NO proved better tumor cell resistance. This review mentions dichotomous nature of NO that may encourage future research assessing the role of NO in cancer prevention and treatment either as a single agent or in combination with other antineoplastic compounds

Diagnostic Accuracy and Agreement between Magnetic Resonance Imaging and Ultrasound Finding for the Diagnosis of Rotator Cuff Tears

Objective: To determine the diagnostic accuracy and agreement between ultrasound and magnetic resonance (MR) imaging in determining rotator cuff tears. Study Design: Cross-sectional study. Place and Duration of the Study: Armed Forces Institute of Radiology and Imaging, Pak Emirates Military Hospital,Rawalpindi Pakistan, from Jul 2018 to Jan 2019. Methodology: Patients of either gender with a traumatic shoulder injury duration of less than 15 days were consecutively included. Rotator cuff tear on ultrasonography was diagnosed on the presence of a hypoechoic discontinuity in the tendon and accentuation of cartilage shadow, giving a 'double cortex' view while on MRI, the hyper-intense signal area within the tendon on T2W, fat-suppressed and GRE sequences, corresponding to fluid signal seen. Results: Of 88 patients, the mean age was 54.022±5.19 years. Ultrasound diagnosed rotator cuff tears in 42(47.7%) patients, and MRI diagnosed rotator cuff tears in 44(50.0%) patients. Diagnostic accuracy of ultrasound taking MR imaging as the gold standard showed sensitivity as 81.82%, specificity as 77.27%, negative predicted value as 78.26%, positive predicted value as 80.95%, and overall diagnostic accuracy as 79.55%. A moderate agreement was found between ultrasound and MRI findings (p-value=0.591). Conclusion: The findings of the current study showed significant moderate agreement between ultrasound and MR imaging in the determination of rotator-cuff tears

An in vitro investigation into the protective and genotoxic effects of myricetin bulk and nano forms in lymphocytes of MGUS patients and healthy individuals

YesThe present study investigated the genoprotective and genotoxic effects of myricetin bulk (10 μM) and nano forms (20 μM) in the lymphocytes from pre-cancerous, monoclonal gammopathy of unknown significance (MGUS) patients and healthy individuals using the Comet and micronucleus assays. The study also evaluated the effect of myricetin on P53 expression levels, using the Western blot technique. Results showed that throughout the in-vitro treatment, lymphocytes from the patients group had higher levels of baseline DNA damage compared to the healthy group. Myricetin in both forms induced significant DNA damage, only at higher concentrations (>40 μM). The micronucleus assay showed a significant reduction (P < 0.01) in the frequency of micronuclei in mono-nucleated cells in the patient group treated with the nano form of myricetin at the non-toxic dose of 20 μM. There was a significant increase in both gene and protein P53 levels in lymphocytes isolated from healthy individuals and pre-cancerous patients. These results suggested a protective effect of myricetin and indicated its nutritional supplement potential for protection against cancer development among patients suffering from MGUS.This study was kindly funded by Mr Nasir Qayyum, Bradford, UK

Ex vivo/in vitro protective effect of myricetin bulk and nano-forms on PhIP-induced DNA damage in lymphocytes from healthy individuals and pre-cancerous MGUS patients

Yes2-Amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP) is a central dietary mutagen, produced when proteinaceous food is heated at very high temperatures potentially causing DNA strand breaks. This study investigates the protective potential of a well-researched flavonoid, myricetin in its bulk and nano-forms against oxidative stress induced ex vivo/in vitro by PhIP in lymphocytes from pre-cancerous monoclonal gammopathy of undetermined significance (MGUS) patients and those from healthy individuals. The results from the Comet assay revealed that in the presence of myricetin bulk (10 µM) and myricetin nano (20 µM), the DNA damage caused by a high dose of PhIP (100 µM) was significantly (P < 0.001) reduced in both groups. However, nano has shown better protection in lymphocytes from pre-cancerous patients. Consistent results were obtained from the micronucleus assay where micronuclei frequency in binucleated cells significantly decreased upon supplementing PhIP with myricetin bulk (P < 0.01) and myricetin nano (P < 0.001), compared to the PhIP treatment alone. To briefly determine the cellular pathways involved in the protective role of myricetin against PhIP, we studied gene expression of P53 and ATR kinase (ATM- and Rad3-related), using the real-time PCR technique

Take-home naloxone kits: attitudes and likelihood-of-use outcomes from a European survey of potential overdose witnesses

Background: Injectable naloxone is already provided as take-home naloxone (THN), and new concentrated intranasal naloxone is now being introduced in Europe. Despite evidence of the effectiveness and cost-effectiveness of THN, little is known about the attitudes of key target populations: people who use opioids (PWUO), family/friends, and staff. We examined the acceptability of different naloxone devices (ampoule, prefilled syringe, and concentrated nasal spray) across 5 European countries. Objectives: The aim of this study was to compare THN target groups (PWUO vs. family/friends vs. staff) in their past rates of witnessed overdose and THN administration (as indicators of future use), current THN device preference, and THN carriage on the day of survey. Method: Cross-sectional survey of respondents (age ≥18) in addiction treatment, harm reduction, and recovery services in Denmark, England, Estonia, Norway, and Scotland. A purpose-developed questionnaire (59 items) was administered in the local language electronically or in a pen-and-paper format. Results: Among n = 725 participants, 458 were PWUO (63.2%), 214 staff (29.5%), and 53 (7.3%) family members. The groups differed significantly in their likelihood-of-future THN use (p < 0.001): PWUO had the highest rate of previously witnessing overdoses (352; 77.7%), and staff members reported the highest past naloxone use (62; 30.1%). Across all groups, most respondents (503; 72.4%) perceived the nasal spray device to be the easiest to use. Most reported willingness to use the spray in an overdose emergency (508; 73.5%), followed by the prefilled syringe (457; 66.2%) and ampoules (64; 38.2%). Average THN carriage was 18.6%, ranging from 17.4% (PWUO) to 29.6% (family members). Conclusion: Respondents considered the concentrated naloxone nasal spray the easiest device to use. Still, most expressed willingness to use the nasal spray as well as the prefilled syringe in an overdose emergency. Carriage rates were generally low, with fewer than 1 in 5 respondents carrying their THN kit on the day of the survey