Extraction of biologically active components from freshwater sapropel

Publisher Copyright: © 2019 Aneka Klavina, Agris Auce, Ivars Vanadzins, Alise Silova, Linda Dobkevica. Copyright: Copyright 2019 Elsevier B.V., All rights reserved.Sapropel has been used for different purposes-in agriculture as fertilizer, in construction as building material, in cosmetic products, in balneology also in medicine and pharmaceuticals as bioactive component. Previously sapropel has been commonly used in raw form and there is no general accepted method or standard method for obtaining sapropel extract. However, most extraction methods follow the same path. Currently, there are few extraction methods using several extractants for obtaining bioactive components from raw sapropel. The most commonly used extractant is alkaline solution. When sapropel is subjected to alkaline environment, the humic and fulvic acids, together with some lipids, vitamins and sugar, present in the raw sapropel become soluble, however other organic and mineral content present in the sapropel remain solid. Alkaline extraction is followed by filtration and water present in the aqueous mixture is evaporated off. Latvian freshwater sapropel can be used as raw material for obtaining sapropel extract and use it as remedy. But the main question for sapropel usage in medicine, balneology and pharmacy is to develop quality criteria for raw sapropel and its extracts. The quality criteria should include minimum requirements for biologically active substance concentration, pH values, antioxidants as well as physical characteristics. In future studies the differences in extract characteristics of the various deposit sites, as well as the stability of the extracts under different storage conditions should be defined; also, there is need for a common approach to develop method of extraction process for active substances from sapropel and analysis procedures of its extract.publishersversionPeer reviewe

EXTRACTION OF BIOLOGICALLY ACTIVE COMPONENTS FROM FRESHWATER SAPROPEL

Sapropel has been used for different purposes - in agriculture as fertilizer, in construction as building material, in cosmetic products, in balneology also in medicine and pharmaceuticals as bioactive component. Previously sapropel has been commonly used in raw form and there is no general accepted method or standard method for obtaining sapropel extract. However, most extraction methods follow the same path. Currently, there are few extraction methods using several extractants for obtaining bioactive components from raw sapropel. The most commonly used extractant is alkaline solution. When sapropel is subjected to alkaline environment, the humic and fulvic acids, together with some lipids, vitamins and sugar, present in the raw sapropel become soluble, however other organic and mineral content present in the sapropel remain solid. Alkaline extraction is followed by filtration and water present in the aqueous mixture is evaporated off. Latvian freshwater sapropel can be used as raw material for obtaining sapropel extract and use it as remedy. But the main question for sapropel usage in medicine, balneology and pharmacy is to develop quality criteria for raw sapropel and its extracts. The quality criteria should include minimum requirements for biologically active substance concentration, pH values, antioxidants as well as physical characteristics. In future studies the differences in extract characteristics of the various deposit sites, as well as the stability of the extracts under different storage conditions should be defined; also, there is need for a common approach to develop method of extraction process for active substances from sapropel and analysis procedures of its extract

The activity of oxidative stress markers in acute respiratory distress syndrome

Publisher Copyright: © by Marina Šarkele 2015.Acute respiratory distress syndrome is a common complication characterised by severe hypoxemia, which leads to high mortality rates in ICU patients. Imbalance between oxidative stress markers like oxidants and antioxidants may play an important role in pathophysiology of the syndrome. We observed 17 ARDS patients during seven days after inclusion, with the main goal to describe dynamic changes in the level of oxidative stress markers in patients with acute respiratory distress syndrome. We found that there are dynamic differences in the level of malondialdechyde (MDA) and nitric oxide (NO) in patients with acute respiratory distress syndrome. There were also different levels of oxidative stress markers in non-survivor compared with survivor groups. Increased level of an oxidant like a thiobarbituric acid substance with malondialdechyde (TBS-MDA) and antioxidant glutathionperoxidase (GPx) at the first day after inclusion was related with poor outcome in patients with acute respiratory distress syndrome.publishersversionPeer reviewe

Mineral element content and antioxidant capacity of some Latvian berries

Berries are widely used in prevention and in adjuvant therapy of different diseases nowadays because of their valuable bioactive agents and antioxidant, antitumor, antiinflammatory properties, nevertheless frequently without medical control. The aim of our study was to determine the element content and antioxidant activities in some Latvian berries (blueberry, Vaccinium corymbosum L., bilberry, Vaccinium myrtillus L. and red berry, Vaccinium vitis-idaea L.). Element content was measured by ICP-OES. Total antioxidant activity was determined by chemiluminometry and hydrogen-donating ability was measured by spectrophotometry. The examined berries contain elements in relatively low concentrations and the consumption of these kind of berries is also poor, although they could be good source for some essential elements: blueberry for Mo, bilberry for Li, Mn, Mo and red berry for Cr, Li, Mn, Mo. On the other hand, they have good antioxidant properties, especially bilberry. Beneficial antioxidant capacities and moderate metal ion concentrations support that berries can complete the diverse diet, and they may be a good supplement in some metal-accumulating disorders

The role of oxidative stress markers in developing of acute respiratory distress syndrome

Publisher Copyright: © by Marina arkele 2015.Acute respiratory distress syndrome (ARDS) is common and multi factorial, clinically described as an inflammatory lung disorder that is associated with major morbidity and high mortality in intensive care patients. Recently, investigators have revised the AECC criteria from 1994. To diagnose ARDS and discover its severity we presently use Berlin definition criteria. An important role in developing of ARDS may be through a disbalance between reactive oxygen species (ROS), which have both oxidant and antioxidant compartments. The pathogenesis of ARDS is very complex, and unfortunately, the dynamic development of ARDS in an individual patient is difficult to recognise. ROS can initiate cellular tissue damage by modifying lipids, proteins and DNA, which can seriously compromise cell life ability or induce a large number of cellular responses through generation of secondary reactive species, leading, at last, to cell death by necrosis or apoptosis. Studies have shown that many patients with organ malfunction at admission to the intensive care units (ICU) show decreased antioxidative properties, worsening the harmful effects of lipid peroxidation. That is the reason why predicting development of ARDS has great value for intensive care specialists.publishersversionPeer reviewe

Biomarkers in community-acquired pneumonia assessment

Copyright: Copyright 2017 Elsevier B.V., All rights reserved.The paper presents information on pneumonia (P) patients with features of oxidative stress (OS). Identifying features of OS in patients with P is of interest not only for diagnosis, but also for monitoring of treatment efficiency. We recruited 73 patients with community-acquired P (CAP), previously healthy adults, both males and females with mean age of 68.0 ± 15.2, hospitalised, and 61 healthy control patients matched for age. For quantitative evaluation of lipid peroxidation in CAP patients, the levels of aldehydic lipid peroxidation products like malondialdehyde (MDA) and 4-hydroxynon-2-enal (HNE) were quantified. Furthermore, concentrations of reduced glutathione (GSH) and several antioxidant enzymes and selenium in plasma were determined. In CAP patients, decreased levels of GSH and plasma selenium were observed. Plasma levels of MDA, and HNE did significantly differ between patient and control groups. We also noted reduced activity of antioxidant enzymes, namely, glutation peroxidase and superoxide dismutase. Low antioxidant enzymes activity was associated with a more severe CAP pattern. Both GSH and antioxidant enzymes may serve as markers for inflammation-related OS in CAP patients, and measurement of these biomarkers may be a valid indentifier for its management.publishersversionPeer reviewe

Oxidative stress parameters in Posttraumatic Stress Disorder risk group patients

Funding Information: The research is supported by European Social Foundation co-financing: Project for Doctoral students support, at Rîga Stradiòð University (No. 2009/0147/1DP/1.1.2.1.2/09/IPIA/ VIAA/009). The views expressed in this article are those of the authors and do not reflect the official policy or position of the Latvian government, Latvian National Armed Forces, Medical Support Centre of Latvian National Armed Forces or any of the institutions with which the authors are affiliated. The authors state no conflict of interest. All authors read and approved the final manuscript.Increased excitotoxity in response to stressors leads to oxidative stress (OS) due to accumulation of excess reactive oxygen/nitrogen species. Neuronal membrane phospholipids are especially susceptible to oxidative damage, which alters signal transduction mechanisms. The Contingent of International Operations (CIO) has been subjected to various extreme stressors that could cause Posttraumatic Stress Disorder (PTSD). Former studies suggest that heterogeneity due to gender, race, age, nutritional condition and variable deployment factors and stressors produce challenges in studying these processes. The research aim was to assess OS levels in the PTSD risk group in CIO. In a prospective study, 143 participants who were Latvian CIO, regular personnel, males, Europeans, average age of 27.4, with the same tasks during the mission, were examined two months before and immediately after a six-month Peace Support Mission (PSM) in Afghanistan. PCL-M questionnaire, valid Latvian language "Military" version was used for PTSD evaluation. Glutathione peroxidase (GPx), superoxide dismutase (SOD) and lipid peroxidation intensity and malondialdehyde (MDA) as OS indicators in blood were determined. Data were processed using SPSS 20.0. The MDA baseline was 2.5582 μM, which after PSM increased by 24.36% (3.1815 μM). The GPx baseline was 8061.98 U/L, which after PSM decreased by 9.35% (7308.31 U/L). The SOD baseline was 1449.20 U/gHB, which after PSM increased by 2.89% (1491.03 U/gHB). The PTSD symptom severity (total PCL-M score) baseline was 22.90 points, which after PSM increased by 14.45% (26.21 points). The PTSD Prevalence rate (PR) baseline was 0.0357, which after PSM increased by 147.06% (0.0882). We conclude that there is positive correlation between increase of OS, PTSD symptoms severity level, and PTSD PR in a group of patients with risk of PTSD - CIO. PTSD PR depends on MDA intensity and OS severity. OS and increased free radical level beyond excitotoxity, is a possible causal factor for clinical manifestation of PTSD.publishersversionPeer reviewe

Glutathione reductase is associated with the clinical outcome of septic shock in the patients treated using continuous veno-venous haemofiltration

Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Background and objectives: At present, there is insufficient evidence to support the use of continuous veno-venous haemofiltration (CVVH) in the early treatment of septic shock. This study focuses on the association between survival and different parameters of oxidative stress (RedOx). Thereby, we evaluated whether RedOx markers are associated with the outcome of septic shock in patients under early-initiated CVVH treatment. Materials and Methods: We conducted a prospective observational study of 65 patients with septic shock who started CVVH within 12 h after hospital admission. Blood samples were taken from each patient prior to the start of CVVH. The following RedOx markers were measured: glutathione peroxidase, glutathione reductase (GR), total antioxidant capacity, superoxide dismutase, nitric oxide, malondialdehyde and 4-hydroxynonenal. The odds ratio (OR) was calculated using binary logistic regression and stepwise multivariable regression. Results: The 65 patients had a median age of 66 years and 39 were male. Based on the outcome, the patients were divided into two groups—non-survivors (n = 29) and survivors (n = 36)—and the levels of RedOx markers were compared between them. Of all the markers, only higher GR activity was found to be significantly associated with the fatal outcome; 100.3 U/L versus 60.5 U/L, OR = 1.027 (95% CI, 1.010–1.044). Following adjustment for the sequential organ failure assessment score and other parameters, GR activity still presented a significant association with the fatal outcome, OR = 1.020 (95% CI, 1.002–1.038). Conclusions: GR activity is associated with in-hospital fatal outcomes among septic shock patients under early-initiated CVVH treatment. Septic shock patients who have a lower GR activity at hospital admission may have a favourable outcome of the early initiation of CVVH.publishersversionPeer reviewe

Rubeosis faciei diabeticorum is not associated with oxidative stress and skin autofluorescence

Funding Information: Riga Stradins University, Doctoral Studies Grant. Publisher Copyright: © 2019Background: Rubeosis faciei diabeticorum is a persistent facial erythema in patients with diabetes mellitus. The actual pathogenesis has not been studied. However, it is speculated to be a cutaneous diabetic microangiopathy. Objective: Examine the correlation between the severity of facial erythema and the possible causes of microvascular diabetic complications, namely oxidative stress, hyperglycemia, and cutaneous accumulation of advanced glycation end-products. Methods: Patients diagnosed with Type 2 diabetes mellitus (n = 32) were enrolled in the study. The facial erythema index was measured using the Mexameter MX18; cutaneous accumulation of advanced glycation end-products was estimated by measuring skin auto fluorescence with the AGE Reader (DiagnOptics Technologies B.V. – Groningen, Netherlands). Glycated haemoglobin, total antioxidant status, and malondialdehyde were measured in blood by TBARS assay. The correlation between the selected variables was assessed by Spearman's rank test; p ≤ 0.05 was considered statistically significant. Results: There was a statistically significant correlation between total antioxidant status and the facial erythema index (ρ = 0.398, p = 0.024). Malondialdehyde, skin autofluorescence, glycated haemoglobin, body mass index, duration of diabetes, and age did not demonstrate statistically significant correlation with the facial erythema index. Study limitations: This is an observational study. Elevation of total antioxidant status could have been caused by several factors that might have also influenced the development of rubeosis faciei, including hyperbilirubinemia and hyperuricemia. Conclusions: The results contradicted expectations. Total antioxidant status correlated positively with facial erythema index; however, there was no correlation with oxidative stress and skin autofluorescence. Further investigations should be conducted to reveal the cause of total antioxidant status elevation in patients with rubeosis faciei.publishersversionPeer reviewe

Changes in Oxidative Stress Parameters and Its Correction Opportunities in Particular Pathologies. Summary of the Doctoral Thesis

Promocijas darbs izstrādāts: Rīgas Stradiņa universitātes Bioķīmijas laboratorijā sadarbībā ar Šefīldas Hallama universitātes Biomedicīnas pētījuma centru un Randox Laboratories, Ltd (AK), P. Stradiņa KUS Aroda un radiācijas medicīnas centru, Kauņas Medicīnas universitātes Endokrinoloģijas klīniku un Lietuvas veselības zinātņu universitātes slimnīcas Kauņas klīniku. Aizstāvēšana: 2015. gada 20. aprīlī plkst. 15.00 Rīgas Stradiņa universitātes Medicīnas promocijas padomes atklātā sēdē Rīgā, Dzirciema ielā 16, Hipokrāta auditorijā.Promocijas darbs ir veltīts divām aktuālām globālām problēmām – 2. tipa cukura diabētam un mazu jonizējošā starojuma devu ilgstošai iedarbībai uz organismu. Diabēta provocēto komplikāciju veidošanā un pēcradiācijas izraisītajās sekās ir iesaistīts oksidatīvais stress, t. i., antioksidatīvā aizsardzības sistēma nespēj pietiekami novērst aktīvo skābekļa formu izraisītos lipīdu, proteīnu un nukleotīdu oksidatīvos bojājumus. Atklājums par aktīvo skābekļa formu ietekmi uz vēža, sirds un asinsvadu, kā arī autoimūno slimību, neirodeģeneratīvo traucējumu, novecošanās u. c. procesu attīstību, kā arī daudzie epidemioloģiskie pētījumi par saslimšanas riska samazināšanos, lietojot uzturā antioksidantiem bagātus produktus, ļāva domāt par jaunu pavērsienu medicīnas zinātnē. Šūnas uz oksidatīvo stresu reaģē ar adaptācijas atbildi, aktivējot reparācijas mehānismus, vai arī, ja bojājumi nopietni – OS inducē šūnas nāvi. Tādējādi pastiprinātas aktīvo skābekļa formu veidošanās un antioksidatīvās sistēmas nepietiekamas efektivitātes dēļ veidojas oksidatīvais stress, kas vēl vairāk veicina patoloģisko procesu attīstību. Pierādīts, ka aktīvās skābekļa formas piedalās diabēta ģenēzē un vēlīnās diabēta izraisītās komplikācijās dažādās orgānu sistēmās. Arī personām, kuras saņēmušas jonizējošās radiācijas apstarojumu, radiācijas ierosinātā aktīvo skābekļa formu ģenerācija izraisa šūnu bojājumus. Jonizējošais starojums ne tikai rada tiešos struktūru bojājumus, bet turpina iedarboties uz organismu ilgtermiņā, lielākoties palielinot iespējas saslimt ar vēzi (t. sk. ar prostatas vēzi), cukura diabētu un citām slimībām, kas saistītas ar aktīvām skābekļa formām. Antioksidantu terapijas izmantošana šobrīd tiek uzskatīta par perspektīvu pieeju, lai ārstētu pacientus, kuriem oksidatīvais stress ir viens no patoģenētiskajiem faktoriem. Oksidatīvā stresa samazināšana, izmantojot antioksidantus, ir regulējošs mehānisms, lai kavētu diabēta ģenēzi un tā izraisīto tālāko komplikāciju rašanos, kā arī jonizējošā starojuma iedarbības sekas. Lai varētu efektīvi veikt farmakoloģisko intervenci, izmantojot antioksidantus, ir svarīgi izzināt aktīvo skābekļa formu izraisīto bojājumu molekulāros mehānismus. Lai gan ir pieejamas dažādas metodes, kā iegūt ar aktīvām skābekļa formām saistītus rādītājus, pašreiz nav standartmetodes oksidatīvā stresa izvērtēšanai. Šobrīd nav noteiktu vadlīniju par preparātiem, kuriem piemīt antioksidatīvās potences – to ievadīšanas laiku, devām, kā arī trūkst farmakokinētisko pētījumu par smagi slimiem cilvēkiem. Jonizējošā starojuma bioloģiskajā iedarbībā uz organismu vēl ir daudz neskaidrību. Klīniskos pētījumos iegūtie dati ir pretrunīgi. Atšķirības, domājams, radušās tāpēc, ka tika lietoti dažādi preparāti, atšķirīgas bija devas un ievadīšanas laiks, kā arī veids (per os, ārīgi, pilienos vai aplikācijās, inhalāciju vai injekciju veidā), dažādas bija pētāmo cilvēku grupas un paraugu skaits. Eksperimentālajos modeļos (pētījumos ar šūnām) parādīts, ka antioksidanti aizsargā pret radiācijas izraisītajām onkoģenētiskajām transformācijām, taču pētījumos ar cilvēkiem efekts izrādījās citāds. Prooksidantu un antioksidantu līdzsvars tiek regulēts vairāku metabolisko procesu norisē, tāpēc praktiski nav iespējams atrast universālu līdzekli, kurš varētu situāciju kardināli mainīt, atliek vien izvēlēties un kombinēt vairākus AO, kam ir dažādi iedarbības mehānismi un kas ir gan ūdenī, gan lipīdos šķīstošie. Darba mērķi: 1) pētīt oksidatīvā stresa koriģēšanas iespējas organismā, lietojot: a) nesteroīdo pretiekaisuma līdzekli ibuprofēnu kombinācijā ar hidrofilajiem un lipofilajiem antioksidantiem personām, kuras saņēmušas mazas jonizējošā starojuma devas, piedaloties Černobiļas AES avārijas seku likvidēšanā; b) preparātus, kas satur polifenolus, 2TCD pacientiem; 2) noteikt oksidatīvā stresa rādītāju izmaiņu atšķirības starp Černobiļas AES avārijas seku likvidētājiem ar / bez 2TCD un 2TCD pacientiem, kuri nebija eksponēti mazas devas jonizējošam starojumam. Darba uzdevums bija izpētīt: 1) svarīgāko oksidatīvā stresa rādītāju izmaiņu nozīmi Černobiļas AES avārijas seku likvidētājiem un izvērtēt nesteroīdā pretiekaisuma līdzekļa ibuprofēna kombinētas lietošanas efektivitāti, lietojot to kopā ar antioksidantiem E vitamīnu un Se (I pētījums), Se un koenzīmu Q10 (II pētījums), uz oksidatīvā stresa līmeni; 2) 2TCD pacientiem oksidatīvā stresa rādītāju izmaiņas un novērtēt dabiskas izcelsmes preparātu, kas satur polifenolus (Ginkgo biloba un zaļās tējas lapu standartizēto ekstraktu, un kombinētā preparāta Grinvitals Cereloba® plus), dažādu devu lietošanas efektivitāti (papildu standartterapijai) uz oksidatīvā stresa rādītāju izmaiņām (III pētījums); 3) oksidatīvā stresa rādītāju izmaiņu atšķirības starp Černobiļas AES avārijas seku likvidētājiem ar / bez 2TCD un 2TCD pacientiem, kuri nebija eksponēti mazas devas jonizējošam starojumam (IV pētījums). I pētījuma rezultāti parādīja, ka ibuprofēns kombinācijā ar antioksidantiem – E vitamīnu un Se – ietekmē oksidatīvā stresa rādītājus, pakāpeniski dinamikā sasniedzot to normalizāciju pētījuma posma beigās. Tajā pašā laikā korelatīvas saistības starp antioksidantiem un prooksidantiem liecināja par oksidatīvā stresa saglabāšanos Černobiļas AES avārijas seku likvidētāju organismā. II pētījuma rezultāti parādīja, ka ibuprofēns kombinācijā ar antioksidantiem – KoQ10 un Se –, regulējot organisma antioksidatīvās aizsardzības sistēmas antiradikālās un antiperoksidatīvās darbības enzīmus un palielinot neenzimātisko antioksidantu daudzumu, kavēja lipīdu peroksidāciju. III pētījuma rezultāti parādīja, ka visefektīvāk uz oksidatīvā stresa rādītājiem 2TCD pacientiem iedarbojās Ginkgo biloba lapu standartizētā ekstrakta lietošana lielākā devā 18 mēnešus, salīdzinot ar lietoto standartterapiju. IV pētījuma rezultāti parādīja, ka izmaiņas antioksidatīvās sistēmas un oksidatīvā stresa rādītājos Černobiļas AES avārijas seku likvidētājiem ar 2TCD, pateicoties adaptācijai oksidatīvā stresa apstākļiem, ir mazāk izteiktas nekā 2TCD pacientiem, kuri nebija eksponēti mazas devas jonizējošam starojumam, bet izmaiņas ir lielākas nekā Černobiļas AES avārijas seku likvidētājiem bez 2TCD un kontroles grupas dalībniekiem. Kopumā pētījumu rezultāti pierādīja oksidatīvā stresa klātbūtni gan 2TCD pacientu, gan Černobiļas AES avārijas seku likvidētāju organismā, un tā pamatoja AO intervences nepieciešamību oksidatīvā stresa koriģēšanai. Promocijas darba rezultāti apliecina, ka antioksidantu intervences dēļ palielinājās antioksidatīvā potence, kas ļāva koriģēt oksidatīvā stresa rādītājus pacientiem ar jonizējošā starojuma iedarbības attālām sekām un 2TCD. Tādējādi dažāda ilguma un vairāku antioksidantu kombināciju lietošana kopā ar pamatterapiju ļautu ievērojami uzlabot pacientu veselību, kavējot slimības progresēšanu.Promocijas darbs veikts ar Eiropas sociālā fonda projekta “Atbalsts doktorantiem studiju programmas apguvei un zinātniskā grāda ieguvei Rīgas Stradiņa universitātē”, finansiālu atbalstu, vienošanās Nr. 2009/0147/1DP/1.1.2.1.2/09/IPIA/VIAA/009