Prosopis Strombulifera Research Articles

Identifying Plant Physiological and Climatic Drivers in the Woody Shrub Prosopis strombulifera: Effects of Spring Traits on Flower Sprouting and Fruit Production

Prosopis strombulifera is a widely distributed woody species distributed along arid ecosystems in America. The interannual evolution of ecophysiological parameters and their effects on fruit production and flower sprouting in Prosopis strombulifera were studied for three years in a natural population distributed in the Atacama Desert. Xylem water column tension, pressure–volume curves, specific leaf area (SLA), and chlorophyll fluorescence parameters were assessed. Flower sprouting was assessed in different weeks using tagged flowers. To assess fruit production, four small containers were placed under twenty-five individuals, allowing the estimation of total annual production and individual production. We found considerable variability between years and between individuals. Positive relationships were found between plant water parameters, SLA, and chlorophyll variables measured in spring at flower sprouting and during fruit production. A negative correlation was found between the mean of the minimum temperatures in spring and flower sprouting. These results suggest that spring ecophysiological parameters strongly affect the reproductive status of P. strombulifera. The results also reflect the potential of this species to adapt to a hyperarid climate by preserving a high relative water content before flower sprouting.

Prosopis strombulifera aqueous extract reduces T cell response and ameliorates type I diabetes in NOD mice.

New products with tolerogenic properties on T cell response are necessary to improve current efficacy, cost and side effects of immunosuppressants. Prosopis strombulifera aqueous extract (PsAE) have reported cytotoxic, antitumoral, antiatherogenic and antileishmanial activities, containing phytochemicals with immune-related activities. Despite these, there are no previous studies with respect to PsAE suppressive properties over T cell proliferation and their function. Because of previous antecedents, this study aims to evaluate the effect of PsAE on T cell activation, proliferation, cytokine production, and to investigate its effect over an invivo model of type 1 diabetes (T1D). Splenocytes and sorted CD4+/CD8+ from wild type C57BL/6 mice were cultured to determine activation, IFN-γ release and T-cell proliferation after polyclonal stimulation. NOD (non-obese diabetic) mice were used to study the effects of orally administered extract on glycemia, insulitis stages and perforin-1 (PRF-1)/granzyme-B (GRZ-B) expression. In primary cultures, the plant extract impairs T cell activation, decreases IFN-γ release, and reduces proliferation after different polyclonal stimuli. Invivo, PsAE improves NOD mice glycemic levels and T1D progression by diminution of pancreas insulitis and reduction of PRF-1 and GRZ-B mRNA expression. To our knowledge, this is the first report characterizing the therapeutic properties of PsAE on T cell activation. The current work provides evidence about invitro and invivo immunosuppressive effects of PsAE and promotes this plant extract as a complementary and alternative treatment in autoimmune T-cell mediated diseases as T1D.

Do Gibberellins Mediate Growth Responses of the Halophytic Woody Prosopis Strombulifera (Lam.) Benth Plants Exposed to Different Sodium Salts?

Do Gibberellins Mediate Growth Responses of the Halophytic Woody Prosopis Strombulifera (Lam.) Benth Plants Exposed to Different Sodium Salts?

Na2SO4 and NaCl salts differentially modulate the antioxidant systems in the highly stress tolerant halophyte Prosopis strombulifera

Prosopis strombulifera (Lam.) Benth. is a halophytic shrub abundant in high-salinity areas in central Argentina, with high tolerance against NaCl but strong growth inhibition by Na2SO4. In the present study, the modulation of the antioxidant systems (enzymatic and non-enzymatic components) was analyzed under different salt treatments (NaCl, Na2SO4 and the iso-osmotic mixture) in hydroponic cultivation. Na2SO4-treated plants showed strong indications of oxidative stress (H2O2 and O2-• increase). Modifications in antioxidant enzymes activities were observed mainly under Na2SO4 treatment, where CAT seems to play an important role in early detoxification of H2O2 in roots, whereas SOD and APX have a predominant role in leaves. As part of the non-enzymatic system, 21 compounds were identified in leaves, being polyphenols the most abundant. Control plants contained the major variety of detected phytochemicals (14). Na2SO4-treated plants contained 10 compounds and NaCl-treated plants nine compounds, but with a different profile. NaCl-treated plants showed the highest antioxidant capacity. Our findings confirm that different types of salt treatments provoke a differential modulation of the antioxidant systems. Polyphenols and other ROS-detoxifying compounds, in a joint action with the enzymatic antioxidant system, are proposed to have a fundamental role in the cellular protection of P. strombulifera plants under severe oxidative stress. Our findings also highlight the potential of this halophyte as a valuable source of bioactive compounds with high antioxidant activity and health benefits.

Therapeutic effect of Prosopis strombulifera (LAM) BENTH aqueous extract on a murine model of cutaneous leishmaniasis

Background and aimProsopis strombulifera (Lam.) Benth is a rhizomatous shrub native from different zones of Argentine Republic. P. strombulifera aqueous extract (PsAE) has different effects and several biological activities have been reported. The goal of this study was to analyze the activity of PsAE on a murine model of cutaneous leishmaniasis caused by Leishmania amazonensis. Experimental procedurePsAE was orally administered at 150 mg/animal/day on BALB/c mice infected in the right footpad (RFP) with 1 × 105 promastigotes of L. amazonensis. As a chemotherapeutic control of treatment, animals receive a commercial form of meglumine antimoniate (MA) (Glucantime®, Aventis, Paris, France). Results and conclusionWe observe that the size of RFP lesions of infected mice without treatment showed a grade of inflammation, ulceration and necrosis at the site of infection much greater than that observed with PsAE or MA treatment. Moreover, PsAE was capable of decreasing parasite burden and splenic index. Furthermore, PsAE treated mice showed a significant decrease in O.D. of total anti-Leishmania IgG antibody responses against L. amazonensis. This decrease was similar to those observed when the reference drug, MA, was used. This would indicate that PsAE treatment inhibits or delays disease progression in mice. In conclusion, our findings suggest that PsAE could be a potential candidate to be used, as a new therapeutic strategy, to treat cutaneous leishmaniasis caused by L. amazonensis.

Current knowledge about Na2SO4 effects on plants: what is different in comparison to NaCl?

In some areas of the world, high levels of sodium sulfate (Na2SO4) are found in the soil together with sodium chloride (NaCl). However, most studies on salinity are performed utilizing only NaCl as a salinizing agent. Generally, plant species have different tolerance/susceptibility responses when grown in the presence of these salts. Some studies showed that Na2SO4 seems to be more inhibitory than NaCl for the growth of species such as barley, wheat, sugar cane, beet, tomato, wild potato, and others. However, studies focusing on how Na2SO4 can affect the biochemical and physiological processes of plants are very scarce. This review provides an overview on the effects of Na2SO4 on different crops and plants species with a special emphasis on the tolerance/non-tolerance mechanisms of the halophyte Prosopis strombulifera under elevated NaCl and Na2SO4. A better understanding of the tolerance mechanisms in this particular species will help to identify cultivars of crop species that are more tolerant to Na2SO4. This knowledge could be used to extent cultivation of certain crop plants on Na2SO4 containing soils.

Antioxidant and Anti-atherogenic Properties of Prosopis strombulifera and Tessaria absinthioides Aqueous Extracts: Modulation of NADPH Oxidase-Derived Reactive Oxygen Species.

Despite popular usage of medicinal plants, their effects as cardiovascular protective agents have not been totally elucidated. We hypothesized that treatment with aqueous extract from Prosopis strombulifera (AEPs) and Tessaria absinthioides (AETa), Argentinian native plants, produces antioxidant effects on vascular smooth muscle cells (VSMCs) and attenuates atherogenesis on apolipoprotein E-knockout (ApoE-KO) mice. In VSMCs, both extracts (5–40 μg/ml) inhibited 10% fetal calf serum-induced cell proliferation, arrested cell in G2/M phase, reduced angiotensin II-induced reactive oxygen species (ROS) generation, and decreased NADPH oxidase subunit expression. In ApoE-KO mice, extracts significantly reduced triglycerides and lipid peroxidation [plasma thiobarbituric acid reactive substances (TBARS)], increased plasma total antioxidant status (TAS), and improved glutathione peroxidase activity in the liver. Under high-fat diet (HFD), both extracts were able to inhibit O2– generation in the aortic tissue and caused a significant regression of atheroma plaques (21.4 ± 1.6% HFD group vs. 10.2 ± 1.2%∗ AEPs group and 14.3 ± 1.0%∗ AETa group; ∗p < 0.01). Consumption of AEPs and AETa produces antioxidant/antimitogenic/anti-atherosclerotic effects, and their use may be beneficial as a complementary strategy regarding cardiovascular disease therapies.

Plant Growth Alterations in Halophyte Prosopis strombulifera (Lam.) Benth. and Natrophile Glycine max (L.) Merril in Response to Salinity and Changes in Auxin Transport

The effects of changes in auxin transport in response to different osmotic potentials (Ψo) were analyzed in the roots and leaves of two leguminous species with different degrees of salt tolerance: the halophyte Prosopis strombulifera (Lam.) Benth. and the glycophyte Glycine max L. The potentials were generated with sodium chloride (NaCl), sodium sulfate (Na2SO4), and the iso-osmotic mixture of both salts (NaCl + Na2SO4). The values evaluated were −1, −1.8, and −2.6 MPa for P. strombulifera, and −0.47, −0.69, and −0.87 MPa for G. max. In addition, the plants were sprayed with 2,3,5-triiodobenzoic acid (TIBA), an auxin transport inhibitor. The parameters measured included root length, shoot height, number of leaves, relative membrane permeability in roots, and endogenous levels of abscisic acid (ABA), indole-3-acetic acid (IAA), and zeatin (Z). Significant responses were observed at the lowest potentials evaluated (−2.6 MPa for P. strombulifera and −0.89 MPa for G. max). Treatment with Na2SO4 inhibited plant growth more than the others, increased the relative membrane permeability, and enhanced ABA production to its highest levels. These toxic effects were slightly reversed in the presence of iso-osmotic mixture. TIBA brought about impaired development in shoots and roots, the highest values for membrane permeability, alterations in the distribution of endogenous ABA, IAA, and Z, as well as harmful effects on the growth response of both species. In general, the alterations in auxin transport intensified the effects of salinity, which confirms the essential role of this mechanism in plants under salt stress or in normal, non-stressful conditions.

UHPLC–Q/Orbitrap/MS/MS fingerprinting and antitumoral effects of Prosopis strombulifera (LAM.) BENTH. queous extract on allograft colorectal and melanoma cancer models

The aqueous extract of the Argentinean native plant, Prosopis strombulifera (PsAE), presents cytotoxicity against human cancer cell lines by inducing cytostasis, necrosis and apoptosis; with diminution of clonogenic survival; without genotoxic effects nor oral animal toxicity. Until now, the chemical extract composition and its in vivo antitumoral properties remain unknown; these studies are the aim of the current work. The PsAE was characterized by chemical fingerprinting and the metabolome was identified by tandem UHPLC-PDA-HESI-Q-orbitrap® mass spectrometry. Colorectal tumors were induced by DMH administration and melanomas resulted from B16-F0 S.C. cells injection; then, animals were treated orally with PsEA. To correlate in vivo results with in vitro cytotoxicity, B16-F0 cell were cultured to determine: cell proliferation and viability by dye exclusion assays, MTT and CFSE dilution; cell cycle distribution by flow cytometry; and immunoblotting of p21cip1, PCNA, cleaved caspase 3, cleaved PARP and TUBA1A. Based on UHPLC-OT-MS and PDA analysis, twenty-six compounds were identified, including: 5 simple organic acids, 4 phenolic acids, 4 procyanidins, 11 flavonoids, and 2 oxylipins. On C57BL6 mice, PsAE significantly increases the median survival on colorectal cancer and reduces the final volume and weight of melanomas. Over cultured cells, the treatment induce over-expression of p21, cytostasis by G2/M cell cycle arrest and apoptosis; while, on in vivo melanomas, treatment up-regulates p21 and slightly decreases PCNA. In conclusion, PsAE is composed by phenolic compounds which demonstrate cytotoxic and antitumoral properties when is orally administrated. Presented results support future research of PsAE as a potential phytomedicine for cancer treatment.

Abscisic acid alters carbohydrate accumulation induced by differential response to sodium salts in the halophyte Prosopis strombulifera

The role of abscisic acid (ABA) was analyzed in roots and leaves of the halophyte Prosopis strombulifera in response to low osmotic potential (Ψo: −1.0, −1.9, and −2.6 MPa) induced by sodium chloride (NaCl), sodium sulfate (Na2SO4), and the iso-osmotic combination of both compounds (NaCl + Na2SO4). P. strombulifera plants were sprayed with ABA, as well as with inhibitors of ABA biosynthesis (sodium tungstate and fluridone). Different parameters were measured, including total plant height, leaf number, root length, root and shoot biomass, water content, transpiration rate, and total soluble carbohydrates, specific carbohydrates and ABA concentrations. Results showed that sodium salts affected growth parameters in varying ways, depending on the type of salts used as well as the osmotic potentials. ABA-sprayed plants displayed the lowest transpiration values. These plants had a higher content of total soluble carbohydrates in roots, greater root biomass and length and increased root/shoot rate. This study shows that ABA triggers different biochemical and physiological responses after the perception of a stressful condition, and that the interaction between different concentrations and types of salts, and the addition of ABA or its inhibitors generates responses that affect development and growth in the halophyte P. strombulifera.

Differential effects of NaCl and Na2SO4 on the halophyte Prosopis strombulifera are explained by different responses of photosynthesis and metabolism

Prosopis strombulifera (Lam.) Benth. is a halophytic shrub found in highly saline soils in Argentina, with high tolerance against NaCl but strong growth inhibition by Na2SO4. In the present study, the differences in the physiological responses caused by these salts and an iso-osmotic combination thereof on photosynthesis, mineral composition and metabolism were analyzed. Na2SO4 treated plants were the most affected by salinity, showing a significant decrease in several photosynthetic parameters. Proline and cysteine accumulated significantly in the plants in response to salt stress. These results show by the first time that the SO42− anion is triggering damage in the photosynthetic apparatus and consequently affecting the photosynthetic process, which may explain the strong growth inhibition in these plants at high salinity. Moreover, the SO42− anion provoke challenges in the incorporation of nutrients, decreasing the levels of K, Ca, P and Mg, and inducing a strong antioxidant activity in P. strombulifera.

Polyamines in Halophytes.

Polyamines (PAs) are related to many aspects of the plant’s life cycle, including responses to biotic and abiotic stress. On the other hand, halophytic plants are useful models for studying salt tolerance mechanisms related to the adaptive strategies that these plants present in adverse environments. Furthermore, some halophytes have high economic value, being recommended instead of glycophytes as alternative agricultural crops in salt-affected coastal zones or saline farmlands. In recent years, the understanding of the role of PAs in salt-tolerant plants has greatly advanced. This mini review reports on the advances in the knowledge of PAs and their participation in achieving better salt tolerance in 10 halophytes. PAs are associated with responses to heavy metals in phytoremediation processes using certain salt-tolerant species (Atriplex atacamensis, A. halimus, Inula chrithmoides, and Kosteletzkya pentacarpos). In crops with exceptional nutritional properties such as Chenopodium quinoa, PAs may be useful markers of salt-tolerant genotypes. The signaling and protection mechanisms of PAs have been investigated in depth in the extreme halophyte Mesembryanthemum crystallinum and Thellungiella spp., enabling genetic manipulation of PA biosynthesis. In Prosopis strombulifera, different biochemical and physiological responses have been reported, depending on the type of salt (NaCl, Na2SO4). Increases in spermidine and spermine have been positively associated with stress tolerance as these compounds provide protection in Cymodocea nodosa, and Solanum chilense, respectively. In addition, abscisic acid and salicylic acid can improve the beneficial effect of PAs in these plants. Therefore, these results indicate the great potential of PAs and their contribution to stress tolerance.

Effect of phenolic compounds present in Argentinian plant extracts on mycelial growth of the plant pathogen Botrytis cinerea Pers.

The polyphagous plant pathogen Botrytis cinerea has theability of growing fast under several conditions, and producing greymoulds in different plant tissues. Because of its adaptive plasticity,resistant strains have made difficult their chemical control. Therefore,new strategies of management and the use of natural compoundscould be important control alternatives. The aim of this work was tostudy the potential value of four Argentine native plant extracts andsome of its phenolic compounds as biodrugs on B. cinerea. Aqueousplant extracts of Larrea divaricata, Prosopis strombulifera, Tessariaabsinthioides and Schinus molle var. areira, were used. The capability toinhibit the mycelial growth was studied using either the crude plantextract or same its most important, detected phenolic compounds.Phenolic compounds were analyzed by Capillary Zone Electrophoresis(CZE) with UV detection, and then statistically analyzed byPrincipal Component Analysis to correlate them and their biologicalactivity against the fungus. Prosopis strombulifera and T. absinthioidesextracts did not inhibit mycelial growth while S. molle stimulated it.Larrea divaricata demonstrated inhibition above 50% at plant extractsconcentrations of 100 mg/mL.

Metabolomic profiling of the halophyte Prosopis strombulifera shows sodium salt- specific response

Primary and secondary metabolite profiles were analyzed in roots and leaves of the halophytic shrub Prosopis strombulifera in response to control plants (no salt added in the growing media) and to lowering the osmotic potential to −1.0, −1.9, and −2.6 MPa generated by NaCl, Na2SO4, and the iso-osmotic combination of them at 24 h after reaching such potential. A rapid production of metabolites in response to sodium salt was found, which was correlated with modifications in growth parameters. Analysis of polar metabolite profiles by GC-MS rendered a total of 108 significantly altered compounds including 18 amino acids, 19 secondary metabolites, 23 carbohydrates, 13 organic acids, 4 indole acids, among others. Primary metabolites showed a differential response under the salt treatments, which was dependent on salt type and concentration, organ and age of plants. Most of identified compounds showed the strongest accumulation at the highest salt concentration assayed for Na2SO4-treated plants, which was correlated with damaging effects of sulfate anion on plant growth. Roots of NaCl-treated plants showed a higher number of altered metabolites (analyzed by UPLC-ESI-QqTOF-MS) compared to other treatments, while leaves of Na2SO4-treated plants showed the highest number of altered signals. A low degree of overlapping between secondary metabolites altered in roots and leaves of NaCl and Na2SO4-treated plants was found. However, when both NaCl and Na2SO4 salts were present plants always showed a lower number of altered metabolites. Three compounds were tentatively identified: tryptophan, lysophosphatidylcoline and 13-hydroxyoctadecadienoic acid. Increasing knowledge on P. strombulifera metabolism will contribute to unravel the underlying biochemical mechanism of salt tolerance.

Salt mixtures induce anatomical modifications in the halophyte Prosopis strombulifera (Fabaceae: Mimosoideae)

Plant morphology, anatomy, ultra-structure and metabolism are deeply affected by salt stress. Although salt mixtures occur naturally in soils there are few studies considering their effect in plant salt tolerance, particularly in halophytes. The aim of the present study was to determine the effects of the salt mixture Na2SO4+NaCl at different concentrations on the anatomy of Prosopis strombulifera, and to compare them with the responses observed earlier in iso-osmotic monosaline cultures. Seedlings were grown hydroponically in Hoagland’s solution adding salt pulses of NaCl+Na2SO4 (25mML−1 and 19mML−1, respectively), every 48h until final Ψo values of −1, −1.9, and −2.6MPa. Control plants were grown under unsalted conditions. The salt-mixture also induced anatomical and histological alterations in roots, stems and leaflets in comparison with control plants and monosaline treated plants. These changes were noticeable from Ψo=−1.9MPa. Reduction in cortical tissues in roots and stems, and reduction in the mesophyll thickness were observed in treated plants, as well as lower number of leaflets. The different degrees of anatomical modifications were dependent on the organ/tissue analyzed and could be particularly attributed to the presence of Cl− or SO42− in the culture medium. Some of them developed features intermediate between those observed in monosaline (NaCl or Na2SO4) treated plants, in agreement with the reversion of the toxic effect of SO42− anion on plant growth under iso-osmotic salt-mixture. We propose that plant anatomical modifications are responses correlated with the chemical nature of the ions present in the medium. When Cl− and SO42− are simultaneously present in the solution, ionic interactions occur determining specific responses which differ in their degree or intensity from those caused by monosaline solutions.

Isolation of a gene encoding a novel atypical LEA protein from the halophyte Prosopis strombulifera with a sodium salt-specific expression

Salinity is one of the major abiotic stresses that adversely affect the crop productivity and growth of the whole plant. The halophytic Prosopis strombulifera (Fabaceae) shrub is a useful plant model to study the molecular and physiological mechanisms involved in salinity tolerance. In this work, the isolation and characterization of the mRNA for a new atypical LEA protein (PsLEA3) is reported. PsLEA3 has alanine as the most abundant amino acid followed by serine. This characteristic is different from typical LEA proteins which have high glycine content. PsLEA3 shows a negative average of hydropathy and remains localized in the chloroplast. The phylogenetic relationship between related LEA proteins and PsLEA3 showed that this protein belongs to the same group as a LEA protein of Arabidopsis. Northern analysis revealed a differential expression of this atypical LEA mRNA in P. strombulifera plants under NaCl and Na2SO4 treatments. Over-expression in roots of Na2SO4-treated plants from Ψo −1.9 MPa was associated with abscisic acid (ABA) and its conjugate (ABA-glucose ester) accumulation as well as with the root length of these plants, showing an inhibition and toxicity induced by sulphate anion present in the medium.

Physiological responses of a halophytic shrub to salt stress by Na2SO4 and NaCl: oxidative damage and the role of polyphenols in antioxidant protection

Salt stress conditions lead to increased production of reactive oxygen species (ROS) in plant cells. Halophytes have the ability to reduce these toxic ROS by means of a powerful antioxidant system that includes enzymatic and non-enzymatic components. In this research, we used the halophytic shrub Prosopis strombulifera to investigate whether the ability of this species to grow under increasing salt concentrations and mixtures was related to the synthesis of polyphenolic compounds and to the maintenance of leaf pigment contents for an adequate photosynthetic activity. Seedlings of P. strombulifera were grown hydroponically in Hoagland's solution, gradually adding Na2SO4 and NaCl separately or in mixtures until reaching final osmotic potentials of -1, -1.9 and -2.6 MPa. Control plants were allowed to develop in Hoagland's solution without salt. Oxidative damage in tissues was determined by H2O2 and malondialdehyde content. Leaf pigment analysis was performed by high-performance liquid chromatography with ultraviolet, and total phenols, total flavonoids, total flavan-3-ols, condensed tannins, tartaric acid esters and flavonols were spectrophotometrically assayed. Treatment with Na2SO4 increased H2O2 production and lipid peroxidation in tissues and induced a sharp increase in flavonoid compounds (mainly flavan-3-ols) and consequently in the antioxidant activity. Also, Na2SO4 treatment induced an increased carotenoid/chlorophyll ratio, which may represent a strategy to protect photosystems against photooxidation. NaCl treatment, however, did not affect H2O2 content, lipid peroxidation, pigments or polyphenols synthesis. The significant accumulation of flavonoids in tissues under Na2SO4 treatment and their powerful antioxidant activity indicates a role for these compounds in counteracting the oxidative damage induced by severe salt stress, particularly, ionic stress. We demonstrate that ionic interactions between different salts in salinized soils modify the biochemical and morpho-physiological responses of P. strombulifera plants to salinity.

Lectotypification in AmericanAcaciaspecies (Fabaceae, Mimosoideae), with Clarifications for Types at the Muséum national d'Histoire naturelle

Lectotypifications are made for three species in Mimosa L. (Fabaceae, Mimosoideae): M. angustisiliqua Lam. [= Desmanthus virgatus (L.) Willd.], M. arabica Lam. [= Vachellia nilotica (L.) P. J. H. Hurter & Mabb.], and M. strombulifera Lam. [≡ Prosopis strombulifera (Lam.) Benth.]. Clarification for type material at the Muséum national d'Histoire naturelle (P) is included for other plants either native to or adventitive in the New World and originally described as Acacia Mill.

Aqueous Extract of Prosopis strombulifera (LAM) BENTH Induces Cytotoxic Effects against Tumor Cell Lines without Systemic Alterations in BALB/c Mice

Prosopis strombulifera (Lam.) Benth. is a rhizomatous shrub native to the northern and central zones of Argentina. The analgesic and antibiotic properties of this plant had been demonstrated but there are no previous reports of its cytotoxic activity. The goal of this work was to analyze the cytotoxic activity of P. strombulifera against HCT-116 and MCF-7 cell lines, and to evaluate toxic systemic effects in BALB/c mice. Changes induced by the aqueous extract from leaves on tumoral cell lines were studied by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide) tetrazolium reduction assay, Trypan blue dye exclusion assay, optical microscopy, Western Blot analysis of PCNA and cPARP, LDH activity, Ames´ test and clonogenic survival. Oral sub-chronic toxicity was assessed on BALB/c mice at concentrations up to 150 mg/animal/day. Analyses included animal/organs weight; erythrocytes, leukocytes and platelets number; and serological determinations of glucose, ASAT, ALAT, urea and creatinine. Extract has induced cytotoxicity, affecting proliferation and viability in both cell lines in a dose and time-response manner. IC50 was 2.25 μg/ml and LC50 5.05 μg/ml in HCT-116, while values were 3.01 μg/ml and 7.52 μg/ml, respectively, in MCF-7. In both cell lines, the antiproliferative effect was confirmed by reduction of PCNA protein expression. When LC50 concentrations were used, extract-induced necrosis (evidenced by the increase in extracellular LDH activity), apoptosis (increased cPARP protein expression) and clonogenic survival diminution. Mutagenic activity of extract was caused at concentrations of 500 μg/ml (99 and 64-fold higher than HCT-116 and MCF-7 LC50 concentrations). Animal studies demonstrated that no significant toxicity was induced. In conclusion, this is the first report of P. strombulifera cytotoxic activity against tumoral cell lines. Sub-chronic extract administration did not cause deleterious effects in vivo. Altogether, the presented results make P. strombulifera a promising natural product for cancer research and treatment.

Growth responses to sulfate and chloride are related to different phytohormone profiles in the halophyte Prosopis strombulifera

In this study, the profile of plant phytohormones traditionally considered as plant growth promoters (GA1, GA3, GA4, IAA and Z) was determined in roots and leaves of the halophyte Prosopis strombulifera grown hydroponically in iso-osmotic solutions of NaCl, Na2SO4 and their mixture. Hormonal levels were correlated with growth parameters and ABA levels. Different sodium salts in the medium differentially affected the synthesis of these compounds. NaCl treated plants showed the greatest accumulation of GA4 and GA1 and lower levels of their metabolites GA8 and GA34 both in root and leaves, in coincidence with the optimum growth observed at ?o -1.9 Mpa this response was also observed at ?o -2.6 MPa. IAA level was unaltered in these plants while Z content was higher in roots than in leaves. In contrast, both leaves and roots from Na2SO4 treated plants showed lower GA1 and GA4 and increased GA8 and GA34 levels at high salinity. High levels of IAA were found in roots of these plants, but the ABA/IAA ratio increased with increasing salt concentrations in the culture medium. This pattern was also observed in the high ABA/GAs ratios. Z levels were very low in all salt treatments. The results of this study show that the halophytic growth under NaCl treatment is mainly regulated by GA1 and GA4 and low relative levels of ABA and IAA. The toxicity of sulfate alters this pattern reversing the ratio ABA/GAs and increasing the synthesis of IAA in conjunction with increased lateral root formation. In bisaline-treated plants intermediate values were observed in the levels of these phytohormones as compared to monosaline treatment.