👤 Magdalena Sobczak

Unilateral vocal fold paralysis (UVFP) due to recurrent laryngeal nerve (RLN) injury is a common cause of dysphonia. No biotherapeutic injectable exists that directs laryngeal reinnervation after RLN injury. Placental-derived connective tissue matrix (pd-CTM) could fill this need, as it contains a plethora of cytokines with potential UVFP therapeutic benefits. This study aimed to identify and quantify the factors in a commercially available pd-CTM (CTM Flow, CTM Biomedical, Lake Worth, Florida) and to study the effects of pd-CTM on vocal fold microenvironment and glottic function in a mouse model of unilateral RLN injury. Cytokine expression (ng/mL) in pd-CTM was characterized using a cytokine array and ELISA. In a separate experiment, C57/BL6 mice were divided into three groups: uninjured negative controls (n = 12), RLN transection with ipsilateral saline thyroarytenoid (TA) injection (n = 16), and RLN transection with ipsilateral pd-CTM TA injection. Outcomes included laryngeal electromyography (L-EMG) and video laryngoscopy after 7 and 28 days, with larynges then harvested and analyzed via immunohistochemistry (IHC) and qPCR. pd-CTM characterization showed moderate-to-high levels of neurotrophic (BDNF, CNTF, GDNF, NTF-3), angiogenic (Angiogenin, VEGF-D), tissue remodeling (bFGF, IGF-1, HGF, TGF-β3), and anti-inflammatory factors (IL-10, IL-1Rα). L-EMG demonstrated increased mean normalized area under the curve ratio in pd-CTM treated mice compared to saline treated mice at the 28-day time point indicating reinnervation (p < 0.001). IHC detected innervated neuromuscular junctions 28 days after pd-CTM treatment. pd-CTM may be a novel treatment option for patients with UVFP based on the neurotrophic, angiogenic, tissue remodeling, and anti-inflammatory factors present. NA. Show less

DOCK7 (dedicator of cytokinesis 7) is a guanidine nucleotide exchange factor (GEF) for Rac1 GTPase that is involved in neuronal polarity and axon generation as well in Schwann cell differentiation and myelination. Recently, we identified DOCK7 as the binding partner of unconventional myosin VI (MVI) in neuronal-lineage PC12 cells and postulated that this interaction could be important in vivo [Majewski et al. (2012) Biochem Cell Biol., 90:565-574]. Herein, we found that MVI-DOCK7 interaction takes also place in other cell lines and demonstrated that MVI cargo domain via its RRL motif binds to DOCK7 C-terminal M2 and DHR2 domains. In MVI knockdown cells, lower Rac1 activity and a decrease of DOCK7 phosphorylation on Tyr1118 were observed, indicating that MVI could contribute to DOCK7 activity. MVI and DOCK7 co-localization was maintained during NGF-stimulated PC12 cell differentiation and observed also in the outgrowths. Also, during differentiation an increase in phosphorylation of DOCK7 as well as of its downstream effector JNK kinase was detected. Interestingly, overexpression of GFP-tagged MVI cargo domain (GFP-GT) impaired protrusion formation indicating that full length protein is important for this process. Moreover, a transient increase in Rac activity observed at 5min of NGF-stimulated differentiation of PC12 cells (overexpressing either GFP or GFP-MVI) was not detected in cells overexpressing the cargo domain. These data indicate that MVI-DOCK7 interaction could have functional implications in the protrusion outgrowth, and full length MVI seems to be important for delivery and maintenance of DOCK7 along the protrusions, and exerting its GEF activity. Show less

Myosin VI (MVI), the only known myosin that walks towards the minus end of actin filaments, is involved in several processes such as endocytosis, cell migration, and cytokinesis. It may act as a transporting motor or a protein engaged in actin cytoskeleton remodelling via its binding partners, interacting with its C-terminal globular tail domain. By means of pull-down technique and mass spectrometry, we identified Dock7 (dedicator of cytokinesis 7) as a potential novel MVI-binding partner in neurosecretory PC12 cells. Dock7, expressed mainly in neuronal cells, is a guanine nucleotide exchange factor (GEF) for small GTPases, Rac1 and Cdc42, which are the major regulators of actin cytoskeleton. MVI-Dock7 interaction was further confirmed by co-immunoprecipitation of endogenous MVI complexed with Dock7. In addition, MVI and Dock7 colocalized in interphase and dividing cells. We conclude that in PC12 cells MVI-Dock7 complexes may function at different cellular locations during the entire cell cycle. Of note, MVI and Dock7 colocalized in primary culture hippocampal neurons also, predominantly in the outgrowths. We hypothesize that this newly identified interaction between MVI and Dock7 may help explain a mechanism for MVI-dependent regulation of actin cytoskeleton organization. Show less

Tobacco smoking, counted as one of the alternating external cardiovascular risk factors, can cause disadvantageous changes of concentration of compounds considered to be the new internal risk factors. The aim of the study was to determine the influence of tobacco smoke on concentration levels of homocysteine, dimethylarginine (ADMA), fibrinogen and C-reactive protein (CRP) in healthy smoking male's blood plasma. 71 healthy male volunteers, aged 30-59, were chosen for the study. Based on a questionnaire they were divided into non-smoking group (37 individuals) and active smokers group (34 individuals). The results obtained indicate the most significant increasing effect of tobacco smoke on blood plasma homocysteine levels (by 11.9%) and then, successively, on fibrinogen (by 10.1%) and ADMA (by 9.1%). Changes of CRP concentration, although differentiated similarly to other factors, were insignificant. Since the coexistence of elevated risk factors shows a synergistic effect on cardiovascular risk level in general, it is advisable to perform tests of new risk factors among people exposed to tobacco smoke. The tests will appoint the ones at risk of disease and help to cover them with a medical care. Show less

The first paper concerning hair nicotine determination was published in 1983 by Ishiyama et al. Since then, examining hair nicotine content has become a valuable tool facilitating assessment of exposure to tobacco smoke in various groups of people (active and passive smokers or even neonates and fetus). The present article describes briefly recent research studies on the use of hair nicotine as a biomarker. Furthermore, the paper describes various determination techniques related to nicotine in hair, as well as advantages and disadvantages of hair nicotine as a biomarker. Show less

Toxic tobacco smoke exposure to human organism is strictly related to progress of atherosclerosis changes. One of the mechanisms of these effects is a change of blood lipoprotein fraction concentrations. The concentrations of the lipid profile parameters (TCL, HDL, LDL, TG) and the chosen biomarkers (urine cotinine and 1-hydroxypyrene and blood carboxyhaemoglobine) were determined. It was studied whether the procedure of the groups determination (nonsmokers, passive and active smokers) affect the calculated average values of lipid profile parameters. The role of the applied biomarkers for the detection of the effects related to the tobacco smoke exposure is also discussed. It is concluded that there is no difference among the lipid profiles of passive smokers and nonsmokers. Cigarette smoking increases and lowers the TG and HDL concentrations, respectively. Urine cotinine seems to be the best indicator of tobacco smoke exposure among three chosen biomarkers. Study subjects were 300 male and female volunteers. Show less

Toxic effects of tobacco smoke may manifest by the increase of concentration of aterogenic compounds in the human body. One of them is asymmetric dimetyloarginine (ADMA) which is perceived not only as a significant risk factor of endothelium dysfunction and cardiovascular disease but also predicts all-cause and cardiovascular mortality independently of established and emerging cardiovascular risk factor. The aim of this work was to check to what degree ADMA concentration in plasma changes for people exposed to tobacco smoke in various intensity. The study population consisted of 168 healthy males between the age of 18 and 60. The exposure to tobacco smoke in examined groups was determined on the basis of questionnaires and cotinine concentration in plasma. Three groups were selected: non-smokers (53 people), passive smokers (48 people) and active smokers (67 people). Insignificant differences of ADMA concentration between passive and active smokers in relation to non-smokers were determined, 15.4% (0.45 vs. 0.39 mmol/l,) and 7.7% (0.42 vs. 0.39 mmol/l) respectively. There was no significant relationship between concentration of ADMA and cotinine in plasma (r=0.173; p=0.239 for passive smokers and r=0.218; p=0.076 for active smokers). The results obtained indicate that tobacco smoke has small influence on ADMA level in healthy males' plasma. Show less

The following biomarkers: cotinine, 1-hydroxypyrene (1-OHP) and carboxyhemoglobin (HbCO) were used for the estimation of the tobacco smoke exposure. In our study urine and blood sampled from 98 volunteers were subjected to assessment of the biomarkers concentrations under investigation. According to the self-reports of the volunteers, all of the volunteers were divided into three groups: non-smokers, passive and active smokers. The mean values of the biomarker concentrations were calculated for these groups. In order to verify the tobacco smoke exposure specified by volunteers, we tested the real urinary cotinine amount. Based on obtained values of this biomarker, the another volunteer's partition into the groups of nonsmokers, passive and active smokers were done. The new mean values for all of these groups were calculated. The mean values obtained for both group partitions differed. The latter partition gave opportunity to use 1-OHP for the estimation of the tobacco smoke exposure not only for the active smokers but also for the passive smokers. When HbCO was taken into consideration as the biomarker, the estimation of the tobacco smoke exposure of the passive smokers was not significant different, as compared with the group of nonsmokers. The analysis of the correlation between the concentrations of 1-OHP and cotinine gave opportunity for the estimation to tobacco smoke exposure of the passive and active smokers. The estimation of the correlation, between the HbCO and cotinine concentrations was restricted for this purpose. Show less

In order to estimate the exposure of passive and active smokers to tobacco smoke one can use the questionnaire method or laboratory examination of chemical compounds being widely accepted exposure biomarkers. Substances that make such biomarkers include some of the tobacco smoke components and its metabolites formed in the body. The study discusses two groups of biomarkers. First, includes substances that serve as exposure markers of carcinogenous properties (metabolites of polycyclic aromatic hydrocarbons, N-nitrosamines, trans,transmuconic acid, S-phenylmercapturic acid). Second group includes substances which role is limited to the evaluation of exposure to tobacco smoke (nicotine, cotinine, anatabine, anabasine, trans-3'-hydroxycotinine, thiocyanate, carboxyhemoglobin, carbon monoxide). Sensitivity and specificity of biomakers used were evaluated, their concentration ranges in physiological fluids in non-smokers, passive-, and active smokers. The simplicity of the examination method was evaluated. Articles published during last two decades indicate that the substance that have all features that make it the most appropriate biomarker is cotinine. It can be assessed in plasma and in urine of smokers and persons exposed to environmental tobacco smoke. Show less

Passive smoking results from involuntary smoke inhalation in the environment where tobacco and other tobacco products are smoked. This is a common situation in numerous public objects, as restaurants, offices, dormitories and students' clubs. Non-smokers are exposed to very high concentrations of tobacco smoke in these places. Environmental exposure to tobacco smoke of the inhabitants of the Pharmacy School dormitory in Sosnowiec was studied. The evaluation was based on urine cotinine concentration measured with the HPLC method. Additionally, a Fagerström test was conducted among declared smokers in order to evaluate the degree of their pharmacologic addiction to nicotine. The obtained results indicate that non-smoking dormitory inhabitants are strongly exposed to environmental tobacco smoke, but active smokers did not presented with pharmacological addiction to nicotine. Show less