Calotropis procera (Aiton) Dryand (Apocynaceae) is an herb that has been commonly used in folk medicine to treat various diseases for more than 1500 years.
Our goal was to investigate the ...anti-metastatic effects of phenolics extracted from C. procera (CphE) against 4T1 breast cancer cells and in BALB/c mice.
4T1 cells were treated with CphE and quercetin (positive control) at concentrations that inhibited cell viability by 50% (IC
). Levels of reactive oxygen species (ROS), wound healing, and protein expressions were determined following standard protocols. For the in vivo pilot study, the syngeneic BALB/c mouse model was used. 4T1 cells were injected into mammary fat pads. Tumors were allowed to grow for 9 days before gavage treatment with CphE (150 mg GAE/kg/day) or PBS (controls) for one week. Excised tumors, liver, and lungs were analyzed for gene and protein expression and histology.
In vitro results showed that CphE suppressed cell viability through apoptosis induction, via caspase-3 cleavage and total PARP reduction. CphE also scavenged ROS and suppressed Akt, mTOR, ERK1/2, CREB, and Src activation contributing to cell motility inhibition. CphE reduced IR, PTEN, TSC2, p70S6, and RPS6, protein levels, which are proteins involved in the PI3K/Akt/mTOR pathway, suggesting this pathway as CphE primary target. In vivo results showed downregulation of ERK1/2 activation by phosphorylation in tumor tissues, accompanied by angiogenesis reduction in tumor and lung tissues. A reduction of Cenpf mRNA levels in liver and lung tissues strongly suggested anti-invasive cancer activity of CphE.
CphE inhibited 4T1 cell signal pathways that play a key role in cell growth and invasion. The potential for in vitro results to be translated in vivo was confirmed. A complete animal study is a guarantee to confirm the CphE anticancer and antimetastatic activity in vivo.
Stand-level competition and local climate influence tree responses to increased drought at the regional scale. To evaluate stand density and elevation effects on tree carbon and water balances, we ...monitored seasonal changes in sap-flow density (SFD), gas exchange, xylem water potential, secondary growth, and non-structural carbohydrates (NSCs) in Abies pinsapo. Trees were subjected to experimental thinning within a low-elevation stand (1200 m), and carbon and water balances were compared to control plots at low and high elevation (1700 m). The hydraulic conductivity and the resistance to cavitation were also characterized, showing relatively high values and no significant differences among treatments. Trees growing at higher elevations presented the highest SFD, photosynthetic rates, and secondary growth, mainly because their growing season was extended until summer. Trees growing at low elevation reduced SFD during late spring and summer while SFD and secondary growth were significantly higher in the thinned stands. Declining NSC concentrations in needles, branches, and sapwood suggest drought-induced control of the carbon supply status. Our results might indicate potential altitudinal shifts, as better performance occurs at higher elevations, while thinning may be suitable as adaptive management to mitigate drought effects in endangered Mediterranean trees.
The biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems. It has been suggested that the ...C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability. The increase in aridity predicted for the twenty-first century in many drylands worldwide may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Consequences of climate change on tree phenology are readily observable, but little is known about the variations in phenological sensitivity to drought between populations within a species. In this ...study, we compare the phenological sensitivity to temperature and water availability in Abies pinsapo Boiss., a drought-sensitive Mediterranean fir, across its altitudinal distribution gradient. Twig growth and needle fall were related to temperature, precipitation and plant water status on a daily scale. Stands located at the top edge of the distributional range showed the most favourable water balance, maximum growth rates and little summer defoliation. Towards higher elevations, the observed delay in budburst date due to lower spring temperatures was overcome by a stronger delay in growth cessation date due to the later onset of strong water-deficit conditions in the summer. This explains an extended growing season and the greatest mean growth at the highest elevation. Conversely, lower predawn xylem water potentials and early partial stomatal closure and growth cessation were found in low-elevation A. pinsapo trees. An earlier and higher summer peak of A. pinsapo litterfall was also observed at these water-limited sites. Our results illustrate the ecophysiological background of the ongoing altitudinal shifts reported for this relict tree species under current climatic conditions.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
There is growing interest in the applications of soil enzymes as early indicators of soil quality change under contrasting agricultural management practices. However, despite there being an abundant ...literature on this subject, most comparative assessments have been based on a limited number of experimental farms and, therefore, conclusions are not as robust as desired. In this study, we compare 18 pairs of organic and neighbouring conventional olive orchards in southern Spain. These sites were selected to allow the definition of the relative contributions of site-landscape features, soil type, and time since organic accreditation and tillage intensity, on the soil quality. Soils were analysed for physico-chemical properties, the activities of dehydrogenase, β-glucosidase, arylsulphatase, acid and alkaline phosphatase, and potential nitrification. The geometric mean of the assayed enzymes (GMea) was validated with an independently performed Principal Component Analysis (PCA), and used as a combined soil quality index. The effects of tillage intensity and time since organic accreditation on the improvement of soil quality were also evaluated within the subset of organic farms. Overall for the 18 sites, contrasted management practices did not differ in their impact on basic soil physico-chemical properties, except for loss of on ignition and available inorganic N which were higher and lower in organic farms, respectively. Organic management resulted in significantly higher soil enzyme activities. However, differences were not significant in some of the paired comparisons when considered individually. This highlights the need for extensive comparative assessment, as in this study, to draw clear conclusions concerning the changes to soil quality under sustainable management practices. The GMea was significantly correlated with the first axis of the PCA and shown to be appropriate for condensing the set of soil enzyme values to a sole numerical value. Soil quality changes in organic versus conventional farms, as measured by the GMea, ranged from −23% to 97%, and was highly dependent on time since organic accreditation (
r
=
0.88;
P
<
0.01). On the other hand, tillage intensity clearly tended to delay any progress in soil quality in the organic farms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•N Africa mixed Moroccan fir-Atlas cedar forests are relevant biodiversity hotspots.•Tree spatial patterns suggest dynamic stability in these forests arisen by:•(i) Niche-segregation processes among ...the two species, and.•(ii) Facilitative effects from initial cedar colonization to late-successional fir stands.•Adaptive management based on cedar establishment may promote fir conservation.
Understanding spatially-explicit interactions between co-existing tree species provides valuable information about the trade-offs between facilitation and competition driving species coexistence and forest dynamics. Here, we analyzed the fine scale spatial pattern of Moroccan fir (Abies marocana) and Cedrus atlantica (Cedrus atlantica) in a mixed forest (Talassemtane National Park, northern Morocco) and discuss its consequences on intra- and inter-specific interactions and stand dynamics. All trees were mapped and measured in ten plots to investigate uni- and bivariate spatial point patterns using pair-correlation and mark correlation functions. Tree ring data was also investigated from increment cores to assess the growth and age patterns of both species. Fir and cedar trees showed similar basal area and mean diameter distributions, while A. marocana presented a higher density and regeneration. There was an overall aggregation of conspecific and heterospecific individuals at small distances up to 2 m. Univariate analysis of tree size classes supports that juveniles of both species, as well as A. marocana adult trees, show an aggregated pattern at fine scales up to 2 m, while C. atlantica adults exhibit a random pattern. Observed spatial patterns are consistent with the hypothesis of attraction mechanisms between fir and adult trees of C. atlantica. Abies marocana recruitment mainly occurred inside the canopy of dominant trees (at distances varying from c.a 1 m under cedar adults to 3 m under adult conspecifics), while C. atlantica was the dominant regeneration in small gaps. The studied A. marocana-C. atlantica mixed forests showed a transition from an initiation phase led by C. atlantica to a subsequent stem exclusion phase, where dominant trees shade out less-competitive trees and mainly fir trees can establish in the forest understory. According to the observed spatial patterns and growth rates, enhancing C. atlantica establishment in degraded areas may be a suitable proactive and adaptive management to promote long-term conservation of endemic Abies marocana under current climate change trends.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Our goal was to evaluate phytochemical characterization and the antitumor potential of Calotropis procera. The phytochemical constitution of the crude extract (CE) revealed the presence of ...flavonoids, glycosides and cardenolide. The MTT assay was used to evaluate the cytotoxicity of CE, methanolic (MF) and ethyl acetate fractions (EAF) of C. procera in canine osteosarcoma cells (OST), canine mammary tumor (CMT), and canine skin fibroblasts (non-tumor cell). Doxorubicin was also used as a positive control. Results showed that CE, MF and EAF promoted a decrease in the viability of OST and CMT cells and did not alter the fibroblasts viability. C. procera also decreased the number of cells, corroborating to the decrease in proliferation and the cell cycle arrest in the G0/G1 phase. It was also evaluated the cell morphology by light and fluorescence microscopy, being demonstrated a reduction in cytoplasmic and cell rounding characteristic of programmed cell death. Moreover, flow cytometry data demonstrated that CE treatment promoted increase of caspase-3 and p53, showing that the cell death was activated in OST cells. In addition, there was a decrease in CD31, VEGF, osteopontin and TGF-β after CE treatment, suggesting that CE exerts its antitumor effect by reducing angiogenesis and tumor progression in OST cells. Moreover, CMT cells showed a reduction in PCNA after treatment with MF and CE. Analyzing the data together, C. procera, especially CE, showed an antitumor potential in both OST and CMT cells, encouraging us to continue investigating its use in cancer therapy.
•Calotropis procera features flavonoids, glycosides and cardenolides.•C. procera reduced canine mammary tumor and osteosarcoma cells viability.•C. procera showed better selectivity index than the positive control-doxorubicin.•C. procera promoted tumor cell cycle arrest in G0/G1.•C. procera induced cell death in osteosarcoma cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Context: The association between thyroid function during pregnancy and the later mental and psychomotor development of the child is supported by numerous experimental, clinical, and epidemiological ...studies.
Objective: The aim of the study was to evaluate the psychological development of infants aged 3 to 18 months whose mothers had received 300 μg of potassium iodide during the first trimester of their pregnancy and compare with infants whose mothers had received no iodine supplements.
Design and Study Subjects: The study included 133 women who had received 300 μg of potassium iodine and 61 women who had received no iodine supplements.
Main Outcome Measures: The neuropsychological status of the children was evaluated with the Bayley Scales of Infant Development, and measurements were made of TSH, free T3, free T4, and urinary iodine.
Results: Those children whose mothers had received an iodine supplement of 300 μg had a more favorable psychometric assessment than those of the other group of mothers. They had higher scores on the Psychomotor Development Index (P = 0.02) and the Behavior Rating Scale.
Conclusions: Dietary iodine supplements not only have no harmful effect on the neurodevelopment of the children, they may even be beneficial. Given the possible presence of confounding variables not controlled for in this study, these findings should be considered as preliminary.
Dietary iodine supplements have a beneficial effect on the neurodevelopment of children.
Abies pinsapo fir forests are remnant of temperate-like coniferous forests currently subjected to the typical seasonal constraints of Mediterranean-type climates. We have examined for the first time, ...P availability and cycling in A. pinsapo forests from southern Spain by using both, measurements of concentrations of soil P fractions (resin extractable P, bicarbonate extractable P and NaOH extractable P) and rates of P supply to (P solubilization, P mineralization and phosphomonoesterases (PMEase activity) and P immobilization from the soil solution. Soils from A. pinsapo stands differing in lithology (serpentinitic and calcareous substrates) and successional status (from young-agradative to old-growth stages) were chosen for this study. Labile organic P fractions, PMEase activity and rates of P gross mineralization and immobilization were significantly higher in agradative stands on serpentines than in successionally comparable calcareous stands. This suggests an important role of the organic P subcycle in the A. pinsapo stand on serpentine. On calcareous lithology, PMEase activity and all soil P transformation rates significantly increased throughout the successional series. Similarly, all organic and inorganic P fractions measured in old-growth forests showed the maximum values of the series. These trends fit the predictions of standard patterns of P cycling changes along with succession, in which P supply to plants greatly depends on solubilization from mineral forms at early-to-mid successional stages, whereas the importance of processes related to the organic P subcycle increases as succession progresses.
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BFBNIB, DOBA, EMUNI, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
20.
Editorial: Biomechanics and oxidative stress Payan-Carreira, Rita; Santos, Dario; Kanagaraj, Subramani ...
Frontiers in bioengineering and biotechnology,
08/2022, Volume:
10
Journal Article
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