scholarly journals Glutathione Protects Lactobacillus sanfranciscensis against Freeze-Thawing, Freeze-Drying, and Cold Treatment

2010 ◽  
Vol 76 (9) ◽  
pp. 2989-2996 ◽  
Author(s):  
Juan Zhang ◽  
Guo-Cheng Du ◽  
Yanping Zhang ◽  
Xian-Yan Liao ◽  
Miao Wang ◽  
...  

ABSTRACT Lactobacillus sanfranciscensis DSM20451 cells containing glutathione (GSH) displayed significantly higher resistance against cold stress induced by freeze-drying, freeze-thawing, and 4°C cold treatment than those without GSH. Cells containing GSH were capable of maintaining their membrane structure intact when exposed to freeze-thawing. In addition, cells containing GSH showed a higher proportion of unsaturated fatty acids in cell membranes upon long-term cold treatment. Subsequent studies revealed that the protective role of GSH against cryodamage of the cell membrane is partly due to preventing peroxidation of membrane fatty acids and protecting Na+,K+-ATPase. Intracellular accumulation of GSH enhanced the survival and the biotechnological performance of L. sanfranciscensis, suggesting that the robustness of starters for sourdough fermentation can be improved by selecting GSH-accumulating strains. Moreover, the results of this study may represent a further example of mechanisms for stress responses in lactic acid bacteria.

Author(s):  
Juan C Begara-Morales ◽  
Capilla Mata-Pérez ◽  
Maria N Padilla ◽  
Mounira Chaki ◽  
Raquel Valderrama ◽  
...  

Abstract Nitro-fatty acids are generated from the interaction of unsaturated fatty acids and nitric oxide (NO)-derived molecules. The endogenous occurrence and modulation throughout plant development of nitro-linolenic acid (NO2-Ln) and nitro-oleic acid (NO2-OA) suggest a key role for these molecules in initial development stages. In addition, NO2-Ln content increases significantly in stress situations and induces the expression of genes mainly related to abiotic stress, such as genes encoding members of the heat shock response family and antioxidant enzymes. The promoter regions of NO2-Ln-induced genes are also involved mainly in stress responses. These findings confirm that NO2-Ln is involved in plant defense processes against abiotic stress conditions via induction of the chaperone network and antioxidant systems. NO2-Ln signaling capacity lies mainly in its electrophilic nature and allows it to mediate a reversible post-translational modification called nitroalkylation, which is capable of modulating protein function. NO2-Ln is a NO donor that may be involved in NO signaling events and is able to generate S-nitrosoglutathione, the major reservoir of NO in cells and a key player in NO-mediated abiotic stress responses. This review describes the current state of the art regarding the essential role of nitro-fatty acids as signaling mediators in development and abiotic stress processes.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 152
Author(s):  
Melita Lončarić ◽  
Ivica Strelec ◽  
Tihomir Moslavac ◽  
Drago Šubarić ◽  
Valentina Pavić ◽  
...  

Lipoxygenases are widespread enzymes that catalyze oxidation of polyunsaturated fatty acids (linoleic, linolenic, and arachidonic acid) to produce hydroperoxides. Lipoxygenase reactions can be desirable, but also lipoxygenases can react in undesirable ways. Most of the products of lipoxygenase reactions are aromatic compounds that can affect food properties, especially during long-term storage. Lipoxygenase action on unsaturated fatty acids could result in off-flavor/off-odor development, causing food spoilage. In addition, lipoxygenases are present in the human body and play an important role in stimulation of inflammatory reactions. Inflammation is linked to many diseases, such as cancer, stroke, and cardiovascular and neurodegenerative diseases. This review summarized recent research on plant families and species that can inhibit lipoxygenase activity.


2018 ◽  
Vol 103 (6) ◽  
pp. 781-788 ◽  
Author(s):  
Geetha Iyer ◽  
Bhaskar Srinivasan ◽  
Shweta Agarwal ◽  
Ruchika Pattanaik ◽  
Ekta Rishi ◽  
...  

PurposeTo analyse the functional and anatomical outcomes of different types of keratoprostheses in eyes with retained silicone oil following vitreoretinal surgery.MethodsRetrospective chart review of patients operated with any type of permanent keratoprosthesis (Kpro) in silicone oil-filled eyes between March 2003 and June 2017 were analysed.Results40 silicone oil-filled eyes underwent keratoprostheses, of which 22 were type 1 and 18 were type 2 Kpros (Lucia variant—nine, modified osteo odonto kerato prosthesis (MOOKP)—four, Boston type 2—three and osteoKpro—two) with a mean follow-up of 61.54 , 42.77, 45.25 , 25 and 37 months, respectively. Anatomic retention of the primary Kpro was noted in 33 eyes (82.5%). A best-corrected visual acuity of better than 20/200 and 20/400 was achieved in 26 (65%)+32 (80%) eyes. Retroprosthetic membrane (RPM) was the most common complication noted in 17 eyes (42.5%). Perioptic graft melt was noted in 4 of 22 eyes of the type 1 Kpro (2 (10.5%) without associated ocular surface disorder (OSD)) and in 1 eye each of Boston and Lucia type 2 Kpro. Laminar resorption occurred in one eye each of the MOOKP and OKP groups. Endophthalmitis and glaucoma did not occur in any eye.ConclusionAppropriately chosen keratoprosthesis is a viable option for visual rehabilitation in eyes post vitreoretinal surgery with retained silicone oil-induced keratopathy not amenable to conventional penetrating keratoplasty. Kpro melt among type 1 Kpro did not occur in 89.5% eyes without associated OSD (19 of 22 eyes), despite the lack of aqueous humour and presence of RPM (4 eyes), two factors considered to play a significant role in the causation of sterile melts. Of interest to note was the absence of infection in any of these eyes. The possible protective role of oil from endophthalmitis is interesting, though yet to be ascertained.


2019 ◽  
Vol 1 (4) ◽  
pp. 13-28
Author(s):  
Abdelmonem Awad Hegazy ◽  
Manal Mohammad Morsy ◽  
Rania Said Moawad ◽  
Gehad Mohammad Elsayed

Background Hypothyroidism is a metabolic disorder affecting the functions of many tissues in the body including the testis. Testis is rich in the polyunsaturated fatty acids content and lacks strong intrinsic antioxidant system making it prone to such oxidative stress. L-carnitine (LC) regulates long chain fatty acids metabolism; and is considered a valuable antioxidant factor. Aim It was to evaluate the effect of hypothyroidism induced by propylthiouracil (PTU) on rats’ testes and the possible protective role of LC. Methods Forty-eight adult male albino rats were used in this work. The animals were divided into three groups with sixteen animals in each. Group 1 (Control): Animals were kept without medications. Group 2 (PTU-treated): was subjected to administration of PTU; while group 3 (PTU and LC) received both PTU and LC. By the end of the experiment “30 days”, blood samples were taken for hormonal assay; then animals were anaesthetized and sacrificed. Specimens were homogenized for biochemical analysis; epididymal content of each rat was obtained immediately for semen analysis. Testes’ specimens were harvested, prepared and examined by light microscope examination. Results Induced hypothyroidism was noticed to cause histopathological, morphometric and biochemical changes in rat’s testes. LC protected the testicular specimens against such changes; it also improved the seminal quality and quantity as well as testicular structure and biochemistry. Conclusion Hypothyroidism could result in hazards to the structure of testis. Fortunately co-administration of LC might reduce such hazards.


1998 ◽  
Vol 329 (1) ◽  
pp. 89-94 ◽  
Author(s):  
C. Mary SUGDEN ◽  
G. D. Lee FRYER ◽  
A. Karen ORFALI ◽  
A. David PRIESTMAN ◽  
Elaine DONALD ◽  
...  

The administration of a low-carbohydrate/high-saturated-fat (LC/HF) diet for 28 days or starvation for 48 h both increased pyruvate dehydrogenase kinase (PDHK) activity in extracts of rat hepatic mitochondria, by approx. 2.1-fold and 3.5-fold respectively. ELISAs of extracts of hepatic mitochondria, conducted over a range of pyruvate dehydrogenase (PDH) activities, revealed that mitochondrial immunoreactive PDHKII (the major PDHK isoform in rat liver) was significantly increased by approx. 1.4-fold after 28 days of LC/HF feeding and by approx. 2-fold after 48 h of starvation. The effect of LC/HF feeding to increase hepatic PDHK activity was retained through hepatocyte preparation, but was decreased on 21 h culture with insulin (100μ-i.u./ml). A sustained (24 h) 2-4-fold elevation in plasma insulin concentration in vivo (achieved by insulin infusion via an osmotic pump) suppressed the effect of LC/HF feeding so that hepatic PDHK activities did not differ significantly from those of (insulin-infused) control rats. The increase in hepatic PDHK activity evoked by 28 days of LC/HF feeding was prevented and reversed (within 24 h) by the replacement of 7% of the dietary lipid with long-chain ω-3 fatty acids. Analysis of hepatic membrane lipid revealed a 1.9-fold increase in the ratio of total polyunsaturated ω-3 fatty acids to total mono-unsaturated fatty acids. The results indicate that the increased hepatic PDHK activities observed in livers of LC/HF-fed or 48 h-starved rats are associated with long-term actions to increase hepatic PDHKII concentrations. The long-term regulation of hepatic PDHK by LC/HF feeding might be achieved through an impaired action of insulin to suppress PDHK activity. In addition, the fatty acid composition of the diet, rather than the fat content, is a key influence.


Sign in / Sign up

Export Citation Format

Share Document