Anti-stress Agent Research Articles

Analysis of the chemical compositions of six essential oils and evaluation of their antioxidant and antibacterial activities against some drug-resistant bacteria in aquaculture

Introduction: The extensive use of chemicals and antimicrobial agents in aquaculture has decreased the immune mechanisms of cultivated species and promoted the emergence of drug-resistant microorganisms leading to diseases among cultivated fish, affecting consumers’ health. Thus, the investigation of natural antibacterial and anti-stress agents is crucial. In the current study, we focused on the evaluation of the potential use of essential oils (EOs) as an antioxidant and antimicrobial agents in aquaculture. Methods: The EOs, obtained by hydrodistillation from clove (Syzygium aromaticum), cinnamon (Cinnamomum verum), rosemary (Rosmarinus officinalis), artemisia (Artemisia herba-alba), cedarwood (Cedrus atlantica) and oregano (Origanum compactum) were analyzed by gas chromatography/mass spectrometry (GC/MS). Their antibacterial activities were carried out against five bacteria, pathogenic to fish in aquaculture, using the well diffusion and microatmosphere methods. The pathogens used were Vibrio anguillarum, Photobacterium damselae subsp damselae, Aeromonas salmonicida, Edwardsiella tarda, and Lactococcus garvieae. Then, the minimum inhibitory and bactericidal concentrations of each EO were determined. Furthermore, the antioxidant activity was performed in vitro. Results: The investigated EOs were effective against the pathogenic strains. They showed variable constituents such as phenols, sesquiterpenes, and monoterpenes. Regarding the antioxidant activity, cinnamon, clove, and oregano EOs showed their abilities to donate hydrogen to 2,2-diphenyl-1-picrylhydrazy (DPPH) radical and scavenge free radicals produced by 2,2-azino-bis-3-ethylbenzothiazoline6-sulfonic acid (ABTS), respectively. Conclusion: These results gave insight into the potential use of phytobiotics in aquaculture as a safe strategy to substitute antibiotics to protect fish from oxidative stress and inhibit the emergence of drug-resistant bacteria for safer consumption of cultivated fish.

Possible cytoprotective mechanisms of oxytocin against 5-fluorouracil-induced gastrointestinal mucositis.

Gastrointestinal mucositis is a common and dose-limiting side effect characterized by ulcerative lesions in the mucosa of the digestive tract in patients receiving anticancer drugs such as 5-fluorouracil (5-FU), a potent antineoplastic drug. Several protocols have reported the efficacy of therapeutic interventions to prevent this side effect, although complete success has not yet been achieved and mucositis remains one of the most serious complications associated with 5-FU therapy. Oxytocin, a well-known antistress agent, has been reported to have comparable effects to ranitidine. Previous studies have shown that oxytocin inhibits gastric acid secretion and the expression of proinflammatory cytokines in rats. If oxytocin can reduce stress-induced ulcers via antioxidant, antiapoptotic, and anti-inflammatory pathways, then it may have a dose-dependent effect on gastrointestinal mucositis caused by 5-FU.

Stress-Relieving Effects of Sesame Oil Aroma and Identification of the Active Components.

(1) Sesame oil aroma has stress-relieving properties, but there is little information on its effective use and active ingredients. (2) Methods: ICR male mice were housed under water-immersion stress for 24 h. Then, the scent of sesame oil or a typical ingredient was inhaled to the stress groups for 30, 60, or 90 min. We investigated the effects of sesame oil aroma on mice behavior and the expression of the dual specificity phosphatase 1 (DUSP1) gene, a candidate stress marker gene in the brain. (3) Results: In an elevated plus-maze test, the rate of entering into the open arm of a maze and the staying time were increased to a maximum after 60 min of inhalation, but these effects decreased 90 min after inhalation. As for the single component, anxiolytic effects were observed in the 2,5-dimethylpyrazine and 2-methoxy phenol group, but the effect was weakened in the furfuryl mercaptan group. The expression levels of DUSP1 in the hippocampus and striatum were significantly decreased in 2,5-dimethylpyrazine and 2-methoxy phenol groups. (4) Conclusions: We clarified the active ingredients and optimal concentrations of sesame oil for its sedative effect. In particular, 2,5-dimethylpyrazine and 2-methoxy phenol significantly suppressed the stress-induced changes in the expression of DUSP1, which are strong anti-stress agents. Our results suggest that these molecules may be powerful anti-stress agents.

Effects of β-1,3-glucan and ascorbic acid on the nutritional-immune response and antioxidant signaling pathways of live tiger grouper during simulated transport

Transport in water is the most common method for transporting live fish in China, however, transport is a strong stressor. Transport stress could lead to a reduced immune and antioxidant system function of tiger grouper, resulting in sickness and death. Besides, tiger grouper were continuously stressed during transport, which resulted in quality deterioration. It is necessary that find a way to relieve the stress of transportation of tiger grouper. Ascorbic acid is not only a good anti-stress agent, but it is also an effective immunostimulant. β-1,3-glucan is a feed additive that can enhance the immune response of fish. Therefore, this study evaluated the effects of β-1,3-glucan and ascorbic acid on the nutritional-immune response and antioxidant signaling pathways of live tiger grouper during simulated transport. Results indicated that adding β-1,3-glucan and ascorbic acid in transport-water muted the increase of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity. In addition, β-1,3-glucan and ascorbic acid activated Nrf2 and mediated TOR expression and then up-regulate related mRNA expression of antioxidant and immune enzymes. We concluded that the application of β-1,3-glucan and ascorbic acid inhibit the increase of metabolism enzymes and inflammatory factors and activate immune and antioxidant signaling pathways to relieve oxidant stress, immune response, and apoptosis. Reducing the loss of amino acids provided nutrients to relieve oxidative stress and immune response, which demonstrated immune-nutritional response in live tiger grouper during simulated transport. These results may provide a new solution for alleviating the decline of immune and antioxidant function of tiger grouper caused by transportation stress.

A STUDY ON Hibiscus sabdariffa LINN CALYX EXTRACT AS A POSSIBLE ANTI-STRESS AGENT IN THE RABBIT AS ANIMAL MODEL

The ability of Hibiscus sabdariffa Linn calyx extract to act as anti-stress agent has been investigated by using its effect on stress-induced changes in serum cholesterol and cortisol levels in the rabbit as a measure of anti-stress action. Relative to zero time serum (zero time post stress) cholesterol value, the 120 minutes value of stressed rabbits treated with water was not significantly changed (67.40 ± 2.32 mg/dL (zero time); 46.80 ± 4.15 mg/dL (120 minutes). However, relative to zero time serum cholesterol value, the 120 minutes value of stressed rabbits treated with Hibiscus sabdariffa Linn calyx extract was significantly (P<0.05) reduced (62.40 ± 5.21 mg/dL (zero time); 27.60 ± 3.11 mg/dL (120 minutes). When compared to the zero time serum cortisol level, the 120 minutes cortisol value of rabbits stressed and treated with water was significantly (P<0.05) reduced (8.76 ± 2.11 ?g/dL (zero time); 5.02 ± 0.95 p,g/dL (120 minutes). For rabbits that were stressed and subsequently treated with Hibiscus sabdariffa Linn calyx extract, the zero time serum cortisol value was not significantly (P>0.05) different from the 120 minutes value, though the latter was lower in value (9.16 ± 1.76ug/dL (zero time); 5.90 ± 1.52 ?g/dL (120 minutes). These data suggest that Hibiscus sabdariffa Linn calyx extract protects against stress-induced changes in serum cholesterol and so possesses anti-stress ability. The apparent inability of the extract to produce significant reduction in serum cortisol status of stressed and extract treated rabbits is discussed.

Do the polyphenolic compounds from natural products can protect the skin from ultraviolet rays?

Excessive exposure to the sun is a major cause that augment the skin cancer, erythema, edema, abnormal pigmentation and finally suppress the immune system. Due to stratospheric ozone depletion and climate change UV levels are increasing, there is an urgent need to protect human skin from the harmful effects of UV. Compounds with photo- protection activity are very useful in reducing the effect of ultraviolet rays. For this reason, today’s sunscreens that contain one or more different types of chemical filters are used to protect the skin from ultraviolet rays. In the market, several synthetic, UV filter molecules are available, but they have limited use because these active molecules may create adverse effects on human skin such as, cancer, estrogenic activity, or photosensitivity reactions, contact dermatitis, mutations. Therefore, the development of formulations containing plant extracts and algae that may be potentially safer is being extensively studied. For this purpose, we can refer to polyphenol compounds such as flavonoids, which are a branch of natural substances that act as catalysts in the optical phase of photosynthesis, and act as anti-stress agents in plants by removing oxygen free radicals. Natural flavonoids have light and direct protection potential due to their ability to absorb ultraviolet rays and due to their antioxidant ability, as well as anti-inflammatory and immune modulating agents. In this article, the sun photoprotection properties of compounds with polyphenolic structure such as flavonoids derived from plant extracts or algae, as well as new methods in optimizing skin protection products against UV radiation have been investigated.

Metabolic profile of canola (Brassica napus L.) seedlings under hydric, osmotic and temperature stresses

Canola is an important oilseed crop and its oil is used in human diet and biodiesel production. Abiotic stressors severely constrain canola growing causing economic losses. Under adverse conditions, plant cells coordinate their metabolic pathways to produce anti-stress agents. The understanding of the metabolic profile can be used to improve target traits since there is a direct relationship with the phenotype. Here we take advantage of the non-targeted metabolite profiling analysis GC–MS technique to assess the differences in metabolite accumulation in canola seedling tissues subjected to heat, waterlogging, drought and salt stresses. Phenotypically, abiotic stresses affected canola root development, mainly in waterlogging, salt and drought conditions, in which root length was increased. We assayed the metabolic profile in each tissue and abiotic stress and organic acids, free amino acid and sugars were detected. Accumulation of these metabolites were variable between shoots and roots under abiotic stresses. Heat stress affected mainly shoots increasing some essential and non-essential amino acids and sucrose while decreasing glucose and fructose contents. Waterlogging also affected mainly shoots decreasing malic and citric acids, some essential and non-essential amino acids and xylose content. Salt stress leads to a reduction of most of the metabolic compounds from organic acids, free amino acid and sugar groups in shoots and roots. Controversially, drought stress resulted in an increasing in most of the metabolite groups in shoots and roots. Shoots presented greater variation in metabolite content in response to abiotic stress. Our data is useful as basic knowledge to improve canola specific traits.

Formation of photosynthetic parameters of winter wheat crops under foliar fertilization and herbicide application

Purpose. To study agronomic measures for the care of winter wheat: the use of foliar fertilization and protection against weeds with sulfonylureas.
 Methods. Field and laboratory.
 Results. It was investigated that the application of Bioforge anti-stress fertilizer did not significantly affect the growth of photosynthetic potential of crops, as the leaf surface area was not significantly different. In addition to the area of the photosynthetic leaf surface, there is a more accurate indicator, that is net productivity of photosynthesis, which can, in our opinion, more accurately show whether the effects of plant protection products against weeds lead to changes in physiological processes in the plant. the mechanism of action of the anti-stress agent is somewhat different. After all, the organization of the photosynthetic apparatus of plants can be such that for a relatively small area of leaves you can get better rates of dry matter accumulation. The best indicators of photosynthetic potential for the use of plant protection products in autumn were identified with the use of such products as Granstar Pro 75, WG, Logran 75, WG, Harmony 75, WG, for introduction into the phenophase BBCH 10–13, and in spring for use in BBCH 27–29 in combination with Bioforge and separately. However, the introduction of PIC 75, WG, to form the best photosynthetic potential of winter wheat crops should be carried out in the phase of BBCH 7–9 in autumn or spring in BBCH 25–26. We also investigated that the use of Bioforge anti-stress fertilizer did not significantly affect the growth of photosynthetic potential of crops.
 Conclusions. It was determined that the use of the anti-stress agent Bioforge had a positive effect on the condition of plants and their accumulation of dry matter. Accordingly, the best indicators of net productivity of wheat photosynthesis were obtained with the use in autumn of such products as Granstar Pro 75, WG, Logran 75, WG, Harmony 75, WG, for introduction into the phenophase BBCH 10–13, and spring for use in BBCH 27–29 in combination with Bioforge. However, the introduction of PIC 75, WG, to form the best photosynthetic potential of winter wheat crops should be carried out in the phase of BBCH 7–9 in autumn or spring in BBCH 25–26 in combination with Bioforge.

Формування продуктивності люпину білого в сучасних кліматичних умовах

Goal. To evaluate the influence of weather conditions in the years of research on the duration of interphase periods and the growing season of white lupine of Chabansky variety, generative development, the formation of the level of yield, and its quality. Methods. Field, weighing and laboratory research methods were used to assess plant growth and development, as well as product quality. By B.A. Dospekhov method of correlation and regression analysis, they identified variability and relationships between these indicators and weather conditions. Results. Weather conditions, which developed in 2016–2020 in the period from sowing to full maturity of white lupine plants, differed significantly over the years of research and affected the duration of the period sowing-seedlings, growing season, plant growth and development, and ultimately — the level of the crop harvest. The most favorable conditions for the formation of the crop were formed in 2016, as evidenced by the highest yield of 4.18 t/ha and the index of conditions of the year 0.69; less favorable in 2018 — 3.95 t/ha and the index of conditions of the year 0.46; in 2019 — 3.60 t/ha and 0.11; in 2017 — 3.14 t/ha and 0.35 respectively. 2020 was the most unfavorable, as indicated by the minimum yield of 2.57 t/ha and the index of annual conditions — 0.92. Weather conditions also affected the quality of the obtained products — the content of crude protein in grain ranged from 33.4 to 36.0%, and its collection depended on the level of crop yield and amounted to 1.48–0.86 t/ha. Conclusions. Peculiarities of interphase periods and duration of growing season of the variety Chabansky of white lupine, plant development, yield level, and grain quality differed depending on meteorological conditions that developed during the growing season during the research years (2016–2020). To reduce the impact of these factors, as well as to obtain a stable grain yield, it is necessary to create varieties that are resistant to adverse conditions, and also to use anti-stress agents and plant growth stimulants.

Adaptogens as anti-stress agents in reducing increased plasma cortisol level during stress

The stress response involves the activation of both the sympathetic-adrenal response and the hypothalamic-pituitary-adrenal axis. During times of increased stress, the adrenal gland is stimulated to produce increased levels of hormones. Cortisol, the main hormone involved in the stress response, is secreted in increased amounts within minutes of a perceived stressor. Cortisol secretion can increase as much as 20-fold and has several important physiological effects. Short-term surges in cortisol levels can suppress inflammation and at the same time suppress immune function. Though inflammation control is important, surges of sustained levels of cortisol are not healthy and ultimately lead to premature aging, degenerative disease, and increased susceptibility to cancer. Studies show that psycho-social stress activates the hypothalamus-pituitary-adrenal axis causing an increase in morning cortisol levels, which correlated to the subjects reports of increased fatigue and anxiety. Although this stress response is important for survival during an acute stressor, prolonged activation of the stress response may lead to adrenal exhaustion in which cortisol levels drop to insufficient levels resulting in fatigue or illness. Many herbs have been shown to impact adrenal function. Adaptogens are plants that produce a non-specific response improving the physiological resistance to stressors. These herbs are often used in the context of adrenal support formulas to balance adrenal hormone levels. It is believed that adaptogenic herbs can increase low levels of adrenal hormone or decrease levels that are elevated. Additionally, these herbs provide balancing activity on many body systems that are impacted by stress, such as the immune response and blood sugar control.In the present study, we have evaluated the efficacy of ethanolic extract of Ocimum sanctum 47mg/kg p.o, Withania somnifera 23 mg/kg p.o and Bacopa monnieri 23 mg/kg p.o on plasma cortisol level in mice subjected to swim endurance test and cold restraint stress. The standard group was administered water-soluble root powder of Panax ginseng 100 mg/kg p.o and the stress control group was administered distilled water orally for 7 days. It was found that mice pretreated with ethanolic extracts of Ocimum sanctum, Withania somnifera and Bacopa monnieri showed a fall in the plasma cortisol level. The standard group also showed a significant decrease in the plasma cortisol level compared to the stress and normal control groups.

Characterization of Dadih: Traditional Fermented Buffalo Milk of Minangkabau

Dadih or dadiah is traditional fermented buffalo milk of Minangkabau, which occurs spontaneously. Dadih is commonly served as ampiang dadih, or other dishes. The microbiota found in dadih are dominated by lactic acid bacteria, and yeasts are also found. The lactic acid bacteria provide functional value, such as antimicrobial, hypocholesterolemic, antimutagenic, antioxidant, and immunomodulatory properties, as well as being the source of γ-aminobutyric acid (GABA) as an anti-stress agent and folate. Nevertheless, many challenges were observed in dadih production, including the limitation of buffalo milk production due to decreasing populations of buffalo in the last two decades, unstandardized dadih production due to the spontaneous fermentation in natural bamboo tubes, and safety problems as no heat treatment is applied in the production of dadih. These problems impede the development of dadih production, thus is it important to improve buffalo cultivation through artificial insemination programs, using different types of milk and pasteurization processes in dadih production, and incubator development to accelerate the fermentation period.

A Brief Review of Swimming Endurance and Chronic Stress Model for Evaluation of Adaptogenic activity

Stress is the disturbed homeostatic condition of the organism, and it is represented by non-specific response of the body to any demand imposed on it. Stress brings various changes in physiological condition of the organism, but various mechanism of the body will counteract to maintain homeostasis. In some situations, body’s adaptation to stress is like reward, which is responsible for improvement of body’s performance beyond its capacity. However if organism suffer strong acute or chronic stress, body is unable to maintain homeostasis. Under this condition, various types of diseases and disorders will develop, and even it may lead to death, if it is not managed at proper time. Hazardous stressful situation can be managed by using antistress agent or adaptogen. These agents improve physical and mental working capacity in severe stress circumstances. In different screening models for evaluation of adoptogenic activity, animals are challenged with acute or chronic stress conditions. Various stimulating, stress protective, tonic responses and biochemical markers were measured in evaluation of adoptogenic activity in these animal models.

Efficacy of Ashwagandha (withania somnifera [l.] Dunal) in improving cardiorespiratory endurance (VO2 max test) in healthy subjects

In Ayurveda, certain herbal formulas are considered to be Rasayana and they are typically taken over periods of time to regenerate both brain and body tissue. Ashwagandha (Withania Somnifera) is used as an adaptogen, antioxidant, immune modulator, free radical scavenger, anti stress, anti arthritic, antispasmodic, anti inflammatory, nervous tonic, nerve soothing and anticancer agent. Ashwagandha (WS) as a nutritional supplement is yet too established. Maximum oxygen uptake (VO2 max) is a gold standard of cardiopulmonary and muscle cell fitness is considered. The study evaluated the efficacy of Ashwagandha to improve cardiorespiratory endurance (VO2 max) in healthy subjects. They randomized single blind controlled comparative clinical study. 54 health volunteers in each group, study group received Ashwagandha Choorna 12gm with milk (200ml) empty stomach in the morning and the control group only milk (200ml). Maximal capacity of oxygen intake in ml/kg/min (VO2 max) with Rockport fitness walking test of both study and control group were measured before intervention (0th day), after the intervention (60th day) and follow up (90th day). A significant improvement in the VO2 max (F=20.675, P <0.0001) and Hemoglobin (X2=74.150 P <0.0001) in the study group was found. Supplementation of Ashwagandha (Withania Somnifera) with milk improve hemoglobin and VO2 max (maximum aerobic capacity).

Effects of Ashwagandha (Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-Analysis.

Ashwagandha (Withania somnifera) is considered a potent adaptogen and anti-stress agent that could have some potential to improve physical performance. This preferred reporting items for systematic reviews and meta-analyses (PRISMA)-based comprehensive systematic review and Bayesian meta-analysis aimed to evaluate clinical trials up to 2020 from PubMed, ScienceDirect, and Google Scholar databases regarding the effect of Ashwagandha supplementation on physical performance in healthy individuals. Besides implementing estimation statistics analysis, we developed Bayesian hierarchical models for a pre-specified subgroup meta-analysis on strength/power, cardiorespiratory fitness and fatigue/recovery variables. A total of 13 studies met the requirements of this systematic review, although only 12 were included in the quantitative analysis. A low-to-moderate overall risk of bias of the trials included in this study was detected. All Bayesian hierarchical models converged to a target distribution (Ȓ = 1) for both meta-analytic effect size (μ) and between-study standard deviation (τ). The meta-analytic approaches of the included studies revealed that Ashwagandha supplementation was more efficacious than placebo for improving variables related to physical performance in healthy men and female. In fact, the Bayesian models showed that future interventions might be at least in some way beneficial on the analyzed outcomes considering the 95% credible intervals for the meta-analytic effect size. Several practical applications and future directions are discussed, although more comparable studies are needed in exercise training, and athletic populations are needed to derive a more stable estimate of the true underlying effect.

Cloacal temperature responses of broiler chickens administered with fisetin and probiotic (Saccharomyces cerevisiae) and exposed to heat stress

Abstract There is dearth information on the role of fisetin as an antistress agent in ameliorating heat stress in broiler chickens. Here, we experimentally compared probiotic, an antioxidant and antistress agent, with fisetin, an antioxidant agent with little or no report on its antistress effect. Sixty-day-old broiler chickens (Arbo Acre breed) were allotted into 4 groups of 15 birds each as follows; control, fisetin, probiotic, and fisetin + probiotic groups, respectively. All administrations were performed orally through gavage for the treatment groups. The environmental and cloacal temperature (CT) parameters were measured bi-hourly at Days 21, 28, and 35 from 7:00 to 7:00 hr, during the period of study. The environmental parameters exceeded the thermoneutral zone for broiler chickens. The probiotic-supplemented group had the least overall mean CT values all through the experimental period. Based on our findings, fisetin was not a potent antistress agent in mitigating heat stress in birds.

Roots and leaves extract from Ashwagandha plant uses in influenza virus and Indian traditional system of medicine

Withania somnifera Dunal (Ashwagandha) plant considered as an excellent Rasayana, health tonic and cure for a number of health complaints. Plants is a diuretic, sedative, anti-inflammatory, increasing energy and acts as an adaptogen that exerts a strong immunostimulatory and anti-stress agent. Ashwagandha plant taken for treating cold and coughs, ulcers, diabetes, leprosy, nervous disorders, rheumatism, arthiritis, intistinal infections, bronchitis, asthma, anticancer, HIV-AIDS, Influenza virus, Corona virus, covid-19 and TB patients. According to Indian herbal system of medicine, it is considered one of the most important herbs and best adaptogenic properties. Leaves extract are contains cuscohydrine, anahygrine, tropine, anaferine, aglycosides, withanolides, starch and amino acids. Withanolids alkoliods from roots and leaves consists of steroidal molecules to fight inflammation and stimulates the immune system, increases memory and helps maintain general health and wellness. Plant is known to increase the production of bone marrow and act anti-ageing, anti-tumor and anti-inflammatory agents. Its steroidal is much higher than that of hydrocarisone which is common treatment in cancer, TB, HIV, Influenza virus, Corona virus, Covid-19 and AIDS activity. It is also recognized as a blood tonic in gynacological disorders including anemia. Anxiety patients can also benefits from Ashwagandha roots and leaves extracts.

Effect of dietary L-tryptophan supplementation and‏ ‏light-emitting diodes on growth ‎and immune response of broilers ‎.

Light-emitting diodes (LEDs) lights are more energy-efficient and provide adequate illumination compared to compact fluorescent (CFL) lamps and incandescent light (ICD) bulbs. However, as new light sources, the LED lights may have a stress effect on broiler chickens. Thus, this study aimed to determine the effects of dietary L-tryptophan (Trp), as an anti-stress agent and different color temperatures of light-emitting diodes on immune responses and growth performance of male broiler chickens. Four hundred and eighty day-old Ross 308 male chicks were used from day 1 to 42. The chicks were randomly distributed into six treatment groups in a 2 × 3 factorial arrangement [0 or 1 g Trp per kg diet along with neutral-white (4286 K), warm-white (2990 K), and incandescent (2790 K) light bulbs] with four replicates of 20 chicks each. Results showed that dietary Trp and Trp×light interaction did not affect growth performance, immune responses, a total number of leukocytes, and different leukocytes count (heterophil, eosinophil, monocyte, and lymphocyte) of male broiler chickens. However, LEDs’ different color temperatures significantly affected the feed conversion ratio (FCR) and primary antibody of sheep red blood cell (SRBC). The FCR was the lowest in the warm-white light, and primary SRBC antibody titers of the chicks were the highest. In conclusion, although adding Trp to male broiler diets did not affect the growth performance and immune responses of chickens, the warm-white light improved the FCR and primary SRBC.

ACTA NON VERBA (з нагоди ювілею проф. Оксани Заячківської)

Oksana Stanislavivna Zayachkivska (born on July 24, 1960, Lviv) – Doctor of Medicine, Professor (2008), Head of the Department of Normal Physiology (2016) at Danylo Halytsky Lviv National Medical University. She is a full member of Shevchenko Scientific Society (SSS) (2018), chairman of the Medical Commission of SSS (2015-2018), Member of the Physiological Society (UK), Global GI Club in FASEB, International Union of Basic and Clinical Pharmacology (IUPHAR-GI section), Honorary Ambassador of Lviv (2019–21). Her ​​research is mainly focused on the problems of the physiology of digestion, stress and the creation of preclinical models of gastrointestinal diseases. Professor studies new stress biomarkers, anti-stress agents and the formation of stress resistance; elucidates molecular mechanisms of cytoprotection. Oksana Zayachkivska is the author and co-author of over 300 scientific original works and translations of the English-language professional literature. She is the member of the Editorial Board and Editor-in-Chief of the “Proceedings of the Shevchenko Scientific Society. Medical Sciences” journal (2015–2020), member of the Editorial boards of “Frontier in Pharmacology” (Switzerland), “Southeast European Medical Journal” (Croatia), “Journal of Clinical Gastroenterology” (USA).

Exogenous l-proline improved Rhodosporidium toruloides lipid production on crude glycerol

BackgroundCrude glycerol as a promising feedstock for microbial lipid production contains several impurities that make it toxic stress inducer at high amount. Under stress conditions, microorganisms can accumulate l-proline as a safeguard. Herein, l-proline was assessed as an anti-stress agent in crude glycerol media.ResultsCrude glycerol was converted to microbial lipids by the oleaginous yeast Rhodosporidium toruloides CGMCC 2.1389 in a two-staged culture mode. The media was supplied with exogenous l-proline to improve lipid production efficiency in high crude glycerol stress. An optimal amount of 0.5 g/L l-proline increased lipid titer and lipid yield by 34% and 28%, respectively. The lipid titer of 12.2 g/L and lipid content of 64.5% with a highest lipid yield of 0.26 g/g were achieved with l-proline addition, which were far higher than those of the control, i.e., lipid titer of 9.1 g/L, lipid content of 58% and lipid yield of 0.21 g/g. Similarly, l-proline also improved cell growth and glycerol consumption. Moreover, fatty acid compositional profiles of the lipid products was found suitable as a potential feedstock for biodiesel production.ConclusionOur study suggested that exogenous l-proline improved cell growth and lipid production on crude glycerol by R. toruloides. The fact that higher lipid yield as well as glycerol consumption indicated that l-proline might act as a potential anti-stress agent for the oleaginous yeast strain.

Methyl jasmonate delays the latency to anoxic convulsions by normalizing the brain levels of oxidative stress biomarkers and serum corticosterone contents in mice with repeated anoxic stress.

Repeated exposure to anoxic stress damages the brain through cortisol-mediated increases in oxidative stress and cellular-antioxidants depletion. Thus, compounds with antioxidant property might confer protection against anoxic stress-induced brain injuries. In this study, we further examined the protective effect of methyl jasmonate (MJ), a potent anti-stress agent against anoxic stress-induced convulsions in mice. Thirty-six male Swiss mice randomized into six groups (n=6) were given MJ (25, 50 and 100mg/kg, i.p.) or vehicle (10mL/kg, i.p.) 30min before 15min daily exposure to anoxic stress for 7days. The latency(s) to anoxic convulsion was recorded on day 7. The blood glucose and serum corticosterone levels were measured afterwards. The brains were also processed for the determination of malondialdehyde, nitrite, and glutathione levels. Methyl jasmonate (MJ) delayed the latency to anoxic convulsion and reduced the blood glucose and serum corticosterone levels. The increased malondialdehyde and nitrite contents accompanied by decreased glutathione concentrations in mice with anoxic stress were significantly attenuated by MJ. These findings further showed that MJ possesses anti-stress property via mechanisms relating to the reduction of serum contents of corticosterone and normalization of brain biomarker levels of oxidative stress in mice with anoxic stress.