Summary
Polyphenols represent one of the most widely distributed molecules in vegetables and fruits with interesting functional and biological properties (antioxidant, antifungal, etc.). By‐products ...issued from agro‐industrial processing represent an inexpensive source of polyphenols; these phenolic compounds can then be extracted and transformed into functional molecules to be used as additives for the food or cosmetic industries. With the objective to enhance polyphenol’s natural properties, considering their low hydrophobicity, lipophilisation of the isolated phenolic compounds was accomplished. The first lipophilisation of ellagitannins issued from pomegranate peel was carried out and, based on our previous work, polyphenols (an anthocyanin and a phenolic acid) extracted from hibiscus flowers were successfully lipophilised. In order to evaluate the impact of lipophilisation on the main properties of these compounds, protocatechuates with different alkyl chain lengths were assessed for their antifungal capacity against a worldwide distributed pathogenic fungus (Fusarium oxysporum), and the new synthesised ellagitannins esters were studied for their antiradical activity in vitro. The results showed that, depending on the chain length, lipophilisation improved the functional properties of the original phenolics. This could be an innovative way to synthesise molecules with an enhanced potential as antioxidants in food, cosmetics or related products.
Lipophilisation improved the functional properties of the original phenolic compounds, that were isolated from natural by‐products.
The polyphenol‐rich pomegranate juice (PJ) and the high‐density lipoprotein (HDL)‐associated paraoxonase1 (PON1) are known as potent atheroprotective antioxidants, but their effects on other tissues ...related to cardiovascular disease (CVD) remain unknown. The current study aimed to investigate the effects of treating mice with PJ or recombinant PON1 (rePON1) on the oxidation and lipid status of CVD‐related tissues: serum, aorta, heart, liver, kidney, visceral, and subcutaneous adipose tissues (VAT and SAT). Both PJ consumption and rePON1 injection decreased the serum levels of thiobarbituric acid‐reactive substances (16% and 19%) and triacylglycerols (TAG, 24% and 27%), while only rePON1 increased the levels of thiol groups (35%) and decreased serum cholesterol (15%). Both PJ and rePON1 significantly decreased aortic cholesterol (38% and 32%) and TAG (62% and 58%) contents in association with downregulation of the key TAG biosynthetic enzyme diacylglycerol O‐acyltransferase 1 (DGAT1, 71% and 65%), while only PJ decreased aortic lipid peroxides (47%). Substantial TAG‐lowering effects of both PJ and rePON1 were observed also in the heart (31% and 42%), liver (34% and 42%), and kidney (42% and 57%). In both VAT and SAT, rePON1 decreased the levels of lipid peroxides (28% and 25%), while PJ decreased the TAG content (22% and 18%). Ex vivo incubation of SAT with serum derived from mice that consumed PJ or injected with rePON1 decreased SAT lipid peroxides (35% or 28%) and TAG mass (12% or 10%). These novel findings highlight potent TAG‐lowering properties of exogenous (PJ) and endogenous (PON1) antioxidants in tissues associated with CVD.
The strong relationship between cardiovascular diseases (CVD), atherosclerosis, and endogenous or exogenous lipids has been recognized for decades, underestimating the contribution of other dietary ...components, such as amino acids, to the initiation of the underlying inflammatory disease. Recently, specific amino acids have been associated with incident cardiovascular disorders, suggesting their significant role in the pathogenesis of CVD. Special attention has been paid to the group of branched-chain amino acids (BCAA), leucine, isoleucine, and valine, since their plasma values are frequently found in high concentrations in individuals with CVD risk. Nevertheless, dietary BCAA, leucine in particular, have been associated with improved indicators of atherosclerosis. Therefore, their potential role in the process of atherogenesis and concomitant CVD development remains unclear. Macrophages play pivotal roles in the development of atherosclerosis. They can accumulate high amounts of circulating lipids, through a process known as macrophage foam cell formation, and initiate the atherogenesis process. We have recently screened for anti- or pro-atherogenic amino acids in the macrophage model system. Our study showed that glycine, cysteine, alanine, leucine, glutamate, and glutamine significantly affected macrophage atherogenicity mainly through modulation of the cellular triglyceride metabolism. The anti-atherogenic properties of glycine and leucine, and the pro-atherogenic effects of glutamine, were also confirmed in vivo. Further investigation is warranted to define the role of these amino acids in atherosclerosis and CVD, which may serve as a basis for the development of anti-atherogenic nutritional and therapeutic approaches.
•Protocatechuic acid (PA) was successfully lipophilized using alcohols from C1 to C18.•Lipophilization could improve PA antioxidant capacity in heterogeneous media.•Antioxidant activity is related to ...compound polarity and method of evaluation.•Protocatechuates could be considered as potential preservatives in food.•An innovative way to add-value to phenolic-rich vegetal extracts is proposed.
Hibiscus sabdariffa L. is a worldwide consumed plant, principally after infusion of its dried sepals and calyces, which are usually discarded. Nevertheless, they represent a potential source of natural bioactive compounds, e.g. polyphenols, which could add value to this under-exploited plant. Protocatechuic acid (PA) was chosen as a model of the phenolic acids that can be extracted from H. sabdariffa. In order to modify PA hydrophilic character, which limits its use in lipid-rich food products, PA was esterified to C1–C18 alcohols, and the impact of lipophilization on its antioxidant activity was evaluated in both, an homogeneous (DPPH and ORAC methods) and an heterogeneous (CAT method) system. Results herein obtained showed that, depending on the grafted alkyl chain length, lipophilization could positively affect the antioxidant activity of PA in heterogeneous media; therefore, support its use as an innovative way to synthesize molecules with an improved antioxidant capacity and potential to be used as multifunctional preservatives in food.
The circulating metabolome provides a snapshot of the physiological state of the organism responding to pathogenic challenges. Here we report alterations in the plasma metabolome reflecting the ...clinical presentation of COVID-19 patients with mild (ambulatory) diseases, moderate disease (radiologically confirmed pneumonitis, hospitalization and oxygen therapy), and critical disease (in intensive care). This analysis revealed major disease- and stage-associated shifts in the metabolome, meaning that at least 77 metabolites including amino acids, lipids, polyamines and sugars, as well as their derivatives, were altered in critical COVID-19 patient's plasma as compared to mild COVID-19 patients. Among a uniformly moderate cohort of patients who received tocilizumab, only 10 metabolites were different among individuals with a favorable evolution as compared to those who required transfer into the intensive care unit. The elevation of one single metabolite, anthranilic acid, had a poor prognostic value, correlating with the maintenance of high interleukin-10 and -18 levels. Given that products of the kynurenine pathway including anthranilic acid have immunosuppressive properties, we speculate on the therapeutic utility to inhibit the rate-limiting enzymes of this pathway including indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase.
Bacteria must often survive following the exhaustion of their external growth resources. Fitting with this need, many bacterial species that cannot sporulate, can enter a state known as long term ...stationary phase (LTSP) in which they can persist for years within spent media. Several recent studies have revealed the dynamics of genetic adaptation of Escherichia coli under LTSP. Yet, the metabolic consequences of such genetic adaptation were not addressed. Here, we characterized the metabolic changes LTSP populations experience, over the first 32 days under LTSP. This allowed us to link genetic adaptations observed in a convergent manner across LTSP populations back to their metabolic adaptive effect. Specifically, we demonstrate that through the acquisition of mutations combinations in specific sets of metabolic genes, E. coli acquires the ability to consume the short chain fatty acid butyrate. Intriguingly, this fatty acid is not initially present within the rich media we used in this study. Instead, it is E. coli itself that produces butyrate during its initial growth within fresh rich media. The mutations that enable butyrate consumption allow E. coli to grow on butyrate. However, the clones carrying these mutations rapidly decrease in frequency, once the butyrate is consumed, likely reflecting an associated cost to fitness. Yet despite this, E. coli populations show a remarkable capability of maintaining these genotypes at low frequency, as standing variation. This in turn allows them to more rapidly re-adapt to consume butyrate, once it again becomes available to them.
On the 21st of May 2023, a dead adult male sperm whale (
) of 13 m in length and estimated weight of around 18,000 kg was reportedly stranded at Playa Los Nogales, La Palma, Canary Islands, Spain. A ...necropsy was performed 48hpm. A 50 cm diameter and 9.5 kg coprolite was found obstructing the caudal colon-rectal lumen. Necro-hemorrhagic lesions were found in heart muscles and three different bacteria of intestinal origin were isolated and identified (
,
and
). It is reported a lethal septicemia of intestinal origin associated with ambergris coprolite as cause of death in this sperm whale.
Limited experimental evidence bridges nutrition and cancer immunosurveillance. Here, we show that ketogenic diet (KD) - or its principal ketone body, 3-hydroxybutyrate (3HB), most specifically in ...intermittent scheduling - induced T cell-dependent tumor growth retardation of aggressive tumor models. In conditions in which anti-PD-1 alone or in combination with anti-CTLA-4 failed to reduce tumor growth in mice receiving a standard diet, KD, or oral supplementation of 3HB reestablished therapeutic responses. Supplementation of KD with sucrose (which breaks ketogenesis, abolishing 3HB production) or with a pharmacological antagonist of the 3HB receptor GPR109A abolished the antitumor effects. Mechanistically, 3HB prevented the immune checkpoint blockade-linked upregulation of PD-L1 on myeloid cells, while favoring the expansion of CXCR3+ T cells. KD induced compositional changes of the gut microbiota, with distinct species such as Eisenbergiella massiliensis commonly emerging in mice and humans subjected to carbohydrate-low diet interventions and highly correlating with serum concentrations of 3HB. Altogether, these results demonstrate that KD induces a 3HB-mediated antineoplastic effect that relies on T cell-mediated cancer immunosurveillance.
•Mapping of conflict-generating projects and conservation efforts in Chile.•There is a dissociation between public policies and biodiversity conservation in Chile.•Most environmental conflicts in ...Chile result from energy generation and mining.•Most projects associated with conflicts are financed by Chilean companies.•101 conflict-generating projects are inside of High Conservation Value Areas.
Biodiversity is vital in the functioning of ecosystems, but it’s permanently being threatened by anthropic impacts derived from productive activities. Thus, conservation has become a global challenge. In Chile, the dissociation between economic activities and conservation has triggered numerous socio-environmental conflicts in recent decades. This work explores how different projects that give rise to these conflicts can represent an underestimated threat to biodiversity.
We identified socio-environmental conflicts in Chile and their associated projects by carrying out an online review of 1035 news articles published between 2004 and 2018 using the key words “environmental conflict”. We selected articles describing a socio-environmental conflict between parties caused by a project or productive sector. Conflict-generating projects were classified by productive sector and capital origin. In addition, their geographical distribution with respect to High Conservation Value Areas (HCVAs, protected areas and priority sites for conservation) was determined.
A total of 283 projects were identified from 14 different productive sectors, most of them related to energy and mining, which threaten biodiversity and human well-being mainly due to pollution and habitat destruction. Chilean companies finance most of the projects, but international companies finance over half of the energy and mining projects. Moreover, 37 % of the projects were located within HCVAs either for the establishment of future protected areas or where protected areas are currently established. As countries make new efforts to maintain and recover biodiversity, it is contradictory not to consider the threats posed by conflict-generating projects to key areas for conservation, both in public policies and in spatial planning instruments.
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