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Frontiers in Plant Science 2023Drought stress is one of the most devastating environmental stressors, especially in the arid and semi-arid regions of the world. Considering the major constraints that...
Effects of drought stress induced by D-Mannitol on the germination and early seedling growth traits, physiological parameters and phytochemicals content of Tunisian squash (Duch.) landraces.
INTRODUCTION
Drought stress is one of the most devastating environmental stressors, especially in the arid and semi-arid regions of the world. Considering the major constraints that drought stress poses to crop production and the consequent yield losses in food crops, breeding for climate-resilient crops is an efficient means to mitigate stress conditions.
MATERIALS AND METHODS
This study aimed at evaluating the response of four squash ( Duchesne) landraces to drought stress at germination and at plant stage. Drought stress was induced by different concentrations of D-mannitol (-0.24, -0.47 and -0.73 MPa). The tested parameters at germination stage included germination percentage, seedling vigor index, seed water absorbance and seedling growth potential. At the plant stage, leaf chlorophyll and carotenoids content, chlorophyll fluorescence, evapotranspiration, photosynthesis activity and several biomarkers, namely malondialdehyde, proline, total phenols content, total flavonoids content and DPPH radical scavenging activity were evaluated in both roots and leaves.
RESULTS AND DISCUSSION
Our results indicate a magnitude of drought stress effects reflected via repression of germination and seedling growth as well as adjustments in physiological functions at later growth stages, in a genotype depended manner. Among landraces, "751" and "746" showed better performance, as evidenced by higher seed germination and seedling growth potential even at high stress levels (-0.47 and - 0.73 MPa), whereas "747" was the most sensitive landrace to drought stress at both tested stages. In conclusion, our findings highlight the importance of squash landraces selection for the identification of elite genotypes with increased tolerance to drought stress.
PubMed: 37600166
DOI: 10.3389/fpls.2023.1215394 -
The Journal of Nutrition Mar 2024Increased intestinal permeability and dysbiosis are related to obesity. Nuts can provide nutrients and bioactive compounds that modulate gut microbiota and inflammation,... (Randomized Controlled Trial)
Randomized Controlled Trial
Daily Cashew and Brazil Nut Consumption Modifies Intestinal Health in Overweight Women on Energy-Restricted Intervention: A Randomized Controlled Trial (Brazilian Nuts Study).
BACKGROUND
Increased intestinal permeability and dysbiosis are related to obesity. Nuts can provide nutrients and bioactive compounds that modulate gut microbiota and inflammation, enhancing the beneficial effects of weight loss.
OBJECTIVES
To evaluate the effect of consuming cashew nuts (Anacardium occidentale L.) and Brazil nuts (Bertholletia excelsa H.B.K) on intestinal permeability and microbiota, fecal SCFAs and pH, inflammation, and weight loss in energy restriction condition.
METHODS
In this 8-week randomized controlled trial, 40 women with overweight or obesity were assigned to energy-restricted groups (-500 kcal/d): control group (free of nuts) or Brazilian nuts group (BN: 30 g of cashew nuts and 15 g of Brazil nuts per day). Permeability was analyzed by the lactulose/mannitol test and the microbiota by sequencing the 16S gene in the V3-V4 regions. Plasma concentrations of inflammatory cytokines (TNF, IL-6, IL-10, IL-8, IL-17A) and C-reactive protein were analyzed.
RESULTS
In total, 25 women completed the intervention. Both groups lost weight without statistical differences. Lactulose excretion increased only in the control group (P < 0.05). The BN consumption increased fecal propionic acid and potentially beneficial bacteria, such as Ruminococcus, Roseburia, strains NK4A214 and UCG-002 from the Ruminococcaceae family, but also Lachnospiraceae family, Bacteroides, and Lachnoclostridium, when compared to the control group. Changes in intestinal permeability were correlated to a greater reduction in body fat (kg), and IL-8, and increases in Ruminococcus abundance.
CONCLUSION
Our findings demonstrate a positive impact of BN consumption within an energy-restricted context, linked to the augmentation of potentially beneficial bacteria and pathways associated with body fat reduction. Besides, BN consumption mitigated increased intestinal permeability, although its capacity to diminish permeability or enhance weight loss proved limited. This trial was registered at the Brazilian Registry of Clinical Trials as ReBEC (ID: RBR-3ntxrm).
Topics: Humans; Female; Nuts; Anacardium; Bertholletia; Overweight; Brazil; Interleukin-8; Lactulose; Obesity; Inflammation; Weight Loss
PubMed: 38246355
DOI: 10.1016/j.tjnut.2023.12.022 -
Neurological Research Jun 2024Controlling elevated intracranial pressure following brain injury with hyperosmolar agents is one of the mainstay treatments in traumatic brain injury patients. In this... (Review)
Review
Comparing the effects of mannitol and hypertonic saline in severe traumatic brain injury patients with elevated intracranial pressure: a systematic review and meta-analysis.
OBJECTIVES
Controlling elevated intracranial pressure following brain injury with hyperosmolar agents is one of the mainstay treatments in traumatic brain injury patients. In this study, we compared the effects of hypertonic saline (HS) and mannitol in reducing increased intracranial pressure.
METHODS
A total of 637 patients from 15 studies were included in our meta-analysis. The primary outcomes were mortality, the length of stay in the hospital and ICU, and the Glasgow Outcome Scale at follow-up.
RESULTS
The mortality in the mannitol group was not statistically different compared to the HS group (RR = 1.55; 95% CI = [0.98, 2.47], = 0.06). The length of stay in the ICU was significantly shorter in the HS group (MD = 1.18, 95% CI = [0.44, 1.92], < 0.01). In terms of favorable neurological outcomes, there was no significant difference between the two agents (RR = 0.92, 95% CI = [0.11, 7.96], = 0.94). The duration of the effect was shorter in the mannitol group than in the HS group (MD = -0.67, 95% CI = [-1.00, -0.33], < 0.01).
DISCUSSION
The results showed that HS and mannitol had similar effects in reducing ICP. Although the HS was associated with a longer duration of effect and shorter ICU stay, other secondary outcomes including mortality rate and favorable neurological outcomes were similar between the two drugs. In conclusion, considering the condition of each patient individually, HS could be a reasonable option than mannitol to reduce ICP in TBI patients.
PubMed: 38825027
DOI: 10.1080/01616412.2024.2360862 -
Journal of Cosmetic Dermatology Jan 2024Chronic exposure to ultraviolet (UV) irradiation causes immunosuppression, photoaging, and carcinogenesis by induction of a cascade of skin damages. Sunscreens currently...
BACKGROUND
Chronic exposure to ultraviolet (UV) irradiation causes immunosuppression, photoaging, and carcinogenesis by induction of a cascade of skin damages. Sunscreens currently on the market are not absorbing UV rays uniformly throughout the full UV range, high sun protection factor (SPF) sunscreens absorb most of UVB rays but are less effective in absorbing the UVA part of the spectrum. In the context, one approach could consist of preserving the skin natural resources and mechanisms, which is the foundation of the ecobiological approach, by combing UV filters and antioxidants to enhance their photoprotective effect.
METHODS
First, the photoprotection properties of ectoine and mannitol association were characterized by the quantification of glutathione, reactive oxygen species, and double-stranded DNA breaks and by the epidermal Langerhans cells functionality. Second, the protection of squalene oxidation, catalase activity, and trans-urocanic acid (UCA) by the ectoine and mannitol association combined or not with SPF30 UV filters was assessed in vivo via non-invasive skin samplings in 10 subjects on irradiated areas.
RESULTS
Using in vitro irradiated skin cell models, we demonstrated that this association significantly preserved intracellular glutathione levels, reduced DNA strand breaks induced by oxidative stress, and maintained Langerhans cell functionality. In vivo this association combined with UV filters presented significantly higher protection of three natural defense systems altered by UV compared to UV filters alone: squalene oxidation, catalase activity, and preservation of trans-UCA.
CONCLUSION
This study demonstrates the ecobiological potential of combining UV filters with biological protection to increase skin photoprotection provided by specific active ingredients with antioxidative and immunosuppressive properties.
Topics: Humans; Sunscreening Agents; Catalase; Squalene; Skin; Ultraviolet Rays; Antioxidants; Glutathione
PubMed: 37539499
DOI: 10.1111/jocd.15893 -
Molecules (Basel, Switzerland) Sep 2023Most of the world's annual production of mannitol is by chemical means, but, due to increasing demand for natural sweeteners, alternative production methods are being...
Most of the world's annual production of mannitol is by chemical means, but, due to increasing demand for natural sweeteners, alternative production methods are being sought. The aim of the study was to screen yeast strains and select culture conditions for the efficient and selective biosynthesis of mannitol from glycerol. From 21 strains examined in the shake-flask culture for mannitol biosynthesis from glycerol (100 g/L), three strains were selected-S2, S3, and S4-and further evaluated in batch bioreactor cultures with technical and raw glycerol (150 g/L). The best production parameters were observed for strain S3, which additionally was found to be the most resistant to NaCl concentration. Next, strain S3 was examined in batch culture with regard to the initial glycerol concentration (from 50 to 250 g/L). It was found that the substrate concentrations of 50 and 75 g/L resulted in the highest mannitol selectivity, about 70%. The fed-batch culture system proposed in this paper (performed in two variants in which glycerol was dosed in four portions of about 50 or 75 g/L) resulted in increased mannitol production, up to 78.5 g/L.
Topics: Glycerol; Sugar Alcohols; Yarrowia; Sweetening Agents; Mannitol; Excipients
PubMed: 37764370
DOI: 10.3390/molecules28186594 -
Journal of Dairy Science Oct 2023This study was conducted to investigate the role of Na on ruminal short-chain fatty acid (SCFA) absorption and barrier function when isolated ruminal epithelium was...
This study was conducted to investigate the role of Na on ruminal short-chain fatty acid (SCFA) absorption and barrier function when isolated ruminal epithelium was exposed to high and low pH ex vivo. Nine Holstein steer calves (322 ± 50.9 kg of body weight) consuming 7.05 ± 1.5 kg dry matter of a total mixed ration were euthanized and ruminal tissue was collected from the caudal-dorsal blind sac. Tissues were mounted between 2 halves of Ussing chambers (3.14 cm) and exposed to buffers that contained low (10 mM) or high (140 mM) Na with low (6.2) or high (7.4) mucosal pH. The same buffer solutions were used on the serosal side except that pH was maintained at 7.4. Buffers used to evaluate SCFA uptake contained bicarbonate to determine total uptake or excluded bicarbonate and included nitrate to determine noninhibitable uptake. Bicarbonate-dependent uptake was calculated as the difference between the total and noninhibitable uptake. Acetate (25 mM) and butyrate (25 mM) were spiked with 2-H-acetate and 1-C-butyrate, respectively, and were then added to the mucosal side, incubated for 1 min, and tissues were analyzed to evaluate rates of SCFA uptake. Tissue conductance (G) and the mucosal-to-serosal flux of 1-H-mannitol were used to assess barrier function. There were no Na × pH interactions for butyrate or acetate uptake. Decreasing mucosal pH from 7.4 to 6.2 increased total acetate and butyrate uptake, and bicarbonate-dependent acetate uptake. Flux of 1-H-mannitol was not affected by treatment. However, high Na concentration reduced G and prevented an increase in G from flux period 1 to flux period 2. The results of this study indicate that although providing more Na to the ruminal epithelium does not affect SCFA uptake or mannitol flux, it may help stabilize tissue integrity.
Topics: Animals; Cattle; Butyrates; Sodium; Bicarbonates; Epithelium; Fatty Acids, Volatile; Acetates; Hydrogen-Ion Concentration; Mannitol; Rumen
PubMed: 37210365
DOI: 10.3168/jds.2022-23052 -
Cells Dec 2023Inflamed and infected tissues can display increased local sodium (Na) levels, which can have various effects on immune cells. In macrophages, high salt (HS) leads to a...
Inflamed and infected tissues can display increased local sodium (Na) levels, which can have various effects on immune cells. In macrophages, high salt (HS) leads to a Na/Ca-exchanger 1 (NCX1)-dependent increase in intracellular Na levels. This results in augmented osmoprotective signaling and enhanced proinflammatory activation, such as enhanced expression of type 2 nitric oxide synthase and antimicrobial function. In this study, the role of elevated intracellular Na levels in macrophages was investigated. Therefore, the Na/K-ATPase (NKA) was pharmacologically inhibited with two cardiac glycosides (CGs), ouabain (OUA) and digoxin (DIG), to raise intracellular Na without increasing extracellular Na levels. Exposure to HS conditions and treatment with both inhibitors resulted in intracellular Na accumulation and subsequent phosphorylation of p38/MAPK. The CGs had different effects on intracellular Ca and K compared to HS stimulation. Moreover, the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5) was not upregulated on RNA and protein levels upon OUA and DIG treatment. Accordingly, OUA and DIG did not boost nitric oxide (NO) production and showed heterogeneous effects toward eliminating intracellular bacteria. While HS environments cause hypertonic stress and ionic perturbations, cardiac glycosides only induce the latter. Cotreatment of macrophages with OUA and non-ionic osmolyte mannitol (MAN) partially mimicked the HS-boosted antimicrobial macrophage activity. These findings suggest that intracellular Na accumulation and hypertonic stress are required but not sufficient to mimic boosted macrophage function induced by increased extracellular sodium availability.
Topics: Humans; Sodium; Cardiac Glycosides; Ouabain; Macrophages; Sodium Chloride; Sodium Chloride, Dietary; Caffeine; Anti-Infective Agents
PubMed: 38132136
DOI: 10.3390/cells12242816 -
Frontiers in Cell and Developmental... 2023In light of the impact of airway barrier leaks in COVID-19 and the significance of vitamin D in COVID-19 outcomes, including airway barrier protection, we investigated...
In light of the impact of airway barrier leaks in COVID-19 and the significance of vitamin D in COVID-19 outcomes, including airway barrier protection, we investigated whether the very common dietary flavonoid quercetin could also be efficacious in supporting airway barrier function. To address this question, we utilized the widely used airway epithelial cell culture model, Calu-3. We observed that treating Calu-3 cell layers with quercetin increased transepithelial electrical resistance while simultaneously reducing transepithelial leaks of 14C-D-mannitol (Jm) and 14C-inulin. The effects of quercetin were concentration-dependent and exhibited a biphasic time course. These effects of quercetin occurred with changes in tight junctional protein composition as well as a partial inhibition of cell replication that resulted in decreased linear junctional density. Both of these effects potentially contribute to improved barrier function. Quercetin was equally effective in reducing the barrier compromise caused by the pro-inflammatory cytokine TNF-α, an action that seemed to derive, in part, from reducing the elevation of ERK 1/2 caused by TNF-α. Quercetin improved Calu-3 barrier function and reduced TNF-α-induced barrier compromise, mediated in part by changes in the tight junctional complex.
PubMed: 38078004
DOI: 10.3389/fcell.2023.1271201 -
Turkiye Parazitolojii Dergisi Mar 2024The aim of this study was to evaluate the pathogenicity of strains with T4, T5, T11, and T12 genotypes by comparing the osmotolerance and thermotolerance...
OBJECTIVE
The aim of this study was to evaluate the pathogenicity of strains with T4, T5, T11, and T12 genotypes by comparing the osmotolerance and thermotolerance characteristics of strains isolated from genotype groups, within species with the same genotype, and from environmental and keratitis cases.
METHODS
In this study, after axenic cultures of 22 strains with T4 (Neff, A, B, D, E), T5, T11, and T12 genotypes isolated from clinical and environmental samples, thermotolerance (37 °C, 39 °C and 41 °C) and osmotolerance (0.5 M, 1 M) tests were performed.
RESULTS
All strains showed growth ability at 37 °C and 0.5 M osmolarity. While all five strains isolated from patients with keratitis showed growth ability at 37 °C and 0.5 M osmolarity, no growth was detected at 41 °C and 1 M osmolarity. When the tolerance characteristics of the strains with the same genotype were evaluated, the strains with the T5 and T4E genotypes showed the same characteristics. When strains with the T4 genotype were evaluated in general, 31.25% of the strains were found to grow at 39 °C and 6.25% at 41 °C. Of the T4Neff strains, only one strain did not show the ability to reproduce at 39 °C and showed a different feature from the other strains. While the strain with the T11 genotype grew at all temperatures, the strain with the T12 genotype did not grow at 41 °C.
CONCLUSION
According to our research results, we believe that tolerance to 39 °C and 1 M mannitol is not an indicator of pathogenicity. More studies with strains are required to clarify this issue.
Topics: Humans; Acanthamoeba; Virulence; Thermotolerance; Genotype; Mannitol
PubMed: 38449362
DOI: 10.4274/tpd.galenos.2024.92408 -
Microbiology Spectrum Aug 2023Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of complicated urinary tract infection (UTI) associated with the use of indwelling urinary...
Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of complicated urinary tract infection (UTI) associated with the use of indwelling urinary catheters. Previous reports have revealed host and pathogen effectors critical for MRSA uropathogenesis. Here, we sought to determine the significance of specific metabolic pathways during MRSA UTI. First, we identified four mutants from the Nebraska transposon mutant library in the MRSA JE2 background that grew normally in rich medium but displayed significantly reduced growth in pooled human urine (HU). This prompted us to transduce the uropathogenic MRSA 1369 strain with the transposon mutants in and (tricarboxylic acid [TCA] cycle), (mannitol metabolism), and (pyruvate oxidation). Notably, , , and were also significantly upregulated in the MRSA 1369 strain upon exposure to HU. Compared to the WT, the MRSA 1369 mutant was significantly defective for (i) growth in HU, and (ii) colonization of the urinary tract and dissemination to the kidneys and the spleen in the mouse model of catheter-associated UTI (CAUTI), which may be attributed to its increased membrane hydrophobicity and higher susceptibility to killing by human blood. In contrast to their counterparts in the JE2 background, the , , and mutants in the MRSA 1369 background grew normally in HU; however, they displayed significant fitness defects in the CAUTI mouse model. Overall, identification of novel metabolic pathways important for the urinary fitness and survival of MRSA can be used for the development of novel therapeutics. While Staphylococcus aureus has historically not been considered a uropathogen, S. aureus urinary tract infection (UTI) is clinically significant in certain patient populations, including those with chronic indwelling urinary catheters. Moreover, most S. aureus strains causing catheter-associated UTI (CAUTI) are methicillin-resistant S. aureus (MRSA). MRSA is difficult to treat due to limited treatment options and the potential to deteriorate into life-threatening bacteremia, urosepsis, and shock. In this study, we found that pathways involved in pyruvate oxidation, TCA cycle, and mannitol metabolism are important for MRSA fitness and survival in the urinary tract. Improved understanding of the metabolic needs of MRSA in the urinary tract may help us develop novel inhibitors of MRSA metabolism that can be used to treat MRSA-CAUTI more effectively.
Topics: Animals; Mice; Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcus aureus; Urinary Tract Infections; Staphylococcal Infections; Catheters, Indwelling; Pyruvates; Mannitol; Anti-Bacterial Agents
PubMed: 37378538
DOI: 10.1128/spectrum.05365-22