Targeting Mammalian 5-Lipoxygenase by Dietary Phenolics as an Anti-Inflammatory Mechanism: A Systematic Review

Anti-inflammatory compounds and a new sesquiterpene lactone from Centaurea gabrieljanae Greuter

The traditional use of Centaurea spp. for anti-inflammatory purposes is widespread among the people in Turkiye. For this, the methanol extract of Centaurea gabrieljanae and sub-fractions of the methanol extract were tested for anti-inflammatory activity using 5-LOX, while their antioxidant activities, total phenol, and total flavonoid contents were also examined. The ethyl acetate fraction exhibited potent anti-inflammatory activity (IC50 = 3.864 ± 0.9 µg/ml), from which five known compounds (astragalin, picein, p-hydroxy benzoic acid, 3,4-dimethoxy-cinnamic acid, 4-hydroxybenzoic acid 4-O-β-glucopyranoside) and a new sesquiterpene lactone named Pterochlorin were obtained. Pterochlorin showed potent anti-inflammatory activity with a value of IC50 12.71 ± 0.7 µg/ml compared to standard indomethacin. Similarly, astragalin was found to be strong (IC50 = 18.23 µg/ml). In addition, 4-hydroxybenzoic acid 4-O-β-glucopyranoside was isolated for the first time in Centaurea species, and its anti-inflammatory activity was tested. This study may be a guide for the discovery of a new anti-inflammatory drug derived from natural sources.

Marrubiin Inhibits Peritoneal Inflammatory Response Induced by Carrageenan Application in C57 Mice

Marrubiin is a diterpene with a long history of a wide range of biological activities. In this study, the anti-inflammatory effects of marrubiin were investigated using several in vitro and in vivo assays. Marrubiin inhibited carrageenan-induced peritoneal inflammation by preventing inflammatory cell infiltration and peritoneal mast cell degranulation. The anti-inflammatory activity was further demonstrated by monitoring a set of biochemical parameters, showing that the peritoneal fluid of animals treated with marrubiin had lower levels of proteins and lower myeloperoxidase activity compared with the fluid of animals that were not treated. Marrubiin exerted the most pronounced cytotoxic activity towards peripheral mononuclear cells, being the main contributors to peritoneal inflammation. Additionally, a moderate lipoxygenase inhibition activity of marrubiin was observed.

Climate-Affected Australian Tropical Montane Cloud Forest Plants: Metabolomic Profiles, Isolated Phytochemicals, and Bioactivities

The Australian Wet Tropics World Heritage Area (WTWHA) in northeast Queensland is home to approximately 18 percent of the nation's total vascular plant species. Over the past century, human activity and industrial development have caused global climate changes, posing a severe and irreversible danger to the entire land-based ecosystem, and the WTWHA is no exception. The current average annual temperature of WTWHA in northeast Queensland is 24 °C. However, in the coming years (by 2030), the average annual temperature increase is estimated to be between 0.5 and 1.4 °C compared to the climate observed between 1986 and 2005. Looking further ahead to 2070, the anticipated temperature rise is projected to be between 1.0 and 3.2 °C, with the exact range depending on future emissions. We identified 84 plant species, endemic to tropical montane cloud forests (TMCF) within the WTWHA, which are already experiencing climate change threats. Some of these plants are used in herbal medicines. This study comprehensively reviewed the metabolomics studies conducted on these 84 plant species until now toward understanding their physiological and metabolomics responses to global climate change. This review also discusses the following: (i) recent developments in plant metabolomics studies that can be applied to study and better understand the interactions of wet tropics plants with climatic stress, (ii) medicinal plants and isolated phytochemicals with structural diversity, and (iii) reported biological activities of crude extracts and isolated compounds.

Mechanistic evaluation of antiarthritic and anti-inflammatory effect of campesterol ester derivatives in complete Freund's adjuvant-induced arthritic rats

Background: Current therapies for RA have limitations and side effects, leading to a growing need for safer treatment options. Natural compounds from plants are gaining attention for their therapeutic benefits and fewer side effects. One such compound is the campesterol derivative, a steroid derivative occurring in plants. Studies have shown that this derivative has anti-inflammatory properties and can impact the expression of pro-inflammatory factors. The primary objective of this study was to explore and assess the potential therapeutic effects of Campesterol Ester Derivatives (CED) utilizing a rat model of arthritis induced by Complete Freund's Adjuvant (CFA). Method: The rats were divided into specific experimental groups and treated with either CED or piroxicam (as a positive control) for a duration of 28 days. We determined the effects of CED on various parameters including paw edema, thermal hyperalgesia, and mechanical allodynia at different time points. Furthermore, serum levels of inflammatory cytokines, oxidative stress markers and histological analyses were performed. Additionally, mRNA expression levels of inflammatory markers, both pro-inflammatory (such as TNF-α, NF-κB, IL-6, COX-1, COX-2, and IL-4) and anti-inflammatory were analyzed. Results: In the arthritic rat model, CED exhibited significant anti-inflammatory effects and resulted in a notable reduction in paw edema levels compared to the control group. Histopathological examination of the treated rats' paws confirmed a decrease in inflammation and tissue damage, including reduced pannus formation and bone erosion. Importantly, there were no observable signs of damage to the liver and kidneys following CED treatment, indicating its safety profile and potential for organ protection. At the molecular level, CED treatment downregulated mRNA expression levels of pro-inflammatory markers, indicating its ability to suppress inflammation. Conversely, certain anti-inflammatory markers were upregulated following CED treatment, suggesting a positive influence on the immune response. The positive effects of CED were not limited to joint inflammation; it also showed systemic benefits by positively influencing hematological and biochemical parameters. Conclusion: CED demonstrated promising therapeutic potential as an anti-inflammatory intervention for arthritis in the experimental rat model. Its ability to reduce inflammation, protect tissues, and improve organ function indicates its multifaceted benefits.

Discriminating geographical origins and determining active substances of water caltrop shells through near-infrared spectroscopy and chemometrics

Near-infrared spectroscopy (NIRS) combined with chemometric methods were used to discriminate the geographical origins of the water caltrop shells from different regions of China. Two active substances, the total phenolic content (TPC) and total flavonoid content (TFC) in the water caltrop shells were determined through the technique as well. Principal component analysis (PCA) combined with linear discriminant analysis (LDA) was adopted to build the geographical discriminant model. Quantitative analysis models of TPC and TFC were built using partial least squares (PLS) regression. 1st derivative and randomization test (RT) methods were used to optimize the quantitative analysis models. It was found that the geographical discriminant model can correctly recognize the water caltrop shells from different regions of China with a total accuracy of 93.33%. The values of TPC and TFC obtained by the optimized models and the standard method are close. The coefficient of determination (R2) and the ratio of prediction to deviation for the two substances were 0.91, 0.89 and 3.02, 3.02, respectively. The results demonstrated the feasibility of NIRS combined with chemometric methods for the geographical discrimination of water caltrop shells and the quantitative analysis of TPC and TFC in water caltrop shells.

Caffeic acid modulates activation of neutrophils and attenuates sepsis-induced organ injury by inhibiting 5-LOX/LTB4 pathway

BACKGROUND

Sepsis is a critical systemic inflammatory syndrome which usually leads to multiple organ dysfunction. Caffeic acid (CA), a phenolic compound derived from various plants, has been proved to be essential in neuroprotection, but its role in septic organ damage is unclear. This research aimed to investigate whether CA protects against organ injury in a mouse model of cecal ligation and puncture (CLP).

METHODS

CA (30 mg/kg) or vehicle was administered by intraperitoneal injection immediately after CLP. The samples of blood, lungs, and livers were collected 24 h later. Organ injury was assessed by histopathological examination (HE staining), neutrophil infiltration (myeloperoxidase fluorescence), oxidative stress levels (MDA, SOD, HO-1), and inflammatory cytokines (TNF-α, IL-1β, and IL-6) release in lung and liver tissues. Neutrophil extracellular trap (NET) formation was analyzed by immunofluorescence. In vitro experiments were performed to investigate the potential mechanisms of CA using small interfering RNA (siRNA) techniques in neutrophils, and the effect of CA on neutrophil apoptosis was analyzed by flow cytometry.

RESULTS

Results showed that CA treatment improved the 7-day survival rate and attenuated the histopathological injury in the lung and liver of CLP mice. CA significantly reduced neutrophil infiltration in the lungs and livers of CLP mice. TNF-α, IL-1β, IL-6 and LTB4 were reduced in serum, lung, and liver of CA-treated CLP mice, and phosphorylation of MAPK (p38, ERK, JNK) and p65 NF-κB was inhibited in lungs and livers. CA treatment further increased HO-1 levels and enhanced superoxide dismutase (SOD) activity, but reduced malondialdehyde (MDA) levels and NET formation. Similarly, in vitro experiments showed that CA treatment and 5-LOX siRNA interference inhibited inflammatory activation and NET release in neutrophils, suppressed MAPK and NF-κB phosphorylation in LPS-treated neutrophils, and decreased LTB4 and cfDNA levels. Flow cytometric analysis revealed that CA treatment reversed LPS-mediated delayed apoptosis in human neutrophils, and Western blot also indicated that CA treatment inhibited Bcl-2 expression but increased Bax expression. CA treatment did not induce further changes in neutrophil apoptosis, inflammatory activation, and NET release when 5-LOX was knocked down by siRNA interference.

CONCLUSIONS

CA has a protective effect on lung and liver injury in a murine model of sepsis, which may be related to inhibition of the 5-LOX/LTB4 pathway.

Unveiling metabotype clustering in resveratrol, daidzein, and ellagic acid metabolism: Prevalence, associated gut microbiomes, and their distinctive microbial networks

The gut microbiota (GM) produces different polyphenol-derived metabolites, yielding high interindividual variability and hampering consistent health effects. GM metabotypes associated with ellagic acid (urolithin metabotypes A (UMA), B (UMB), and 0 (UM0)), resveratrol (lunularin -producers (LP) and non-producers (LNP)), and daidzein (equol-producers (EP) and non-producers (ENP)) are known. However, individual polyphenol-related metabotypes do not occur individually. In contrast, different combinations coexist (i.e., metabotype clusters, MCs). We report here for the first time these MCs, their distribution, and their associated GM in adult humans (n = 127) after consuming for 7 days a nutraceutical (pomegranate, Polygonum cuspidatum, and red clover extracts) containing ellagitannins + ellagic acid, resveratrol, and isoflavones. Urine metabolites (UHPLC-QTOF-MS) and fecal microbiota (16S rRNA sequencing) were analyzed. Ten MCs were identified: LP + UMB + ENP (22.7%), LP + UMA + ENP (21.3%), LP + UMA + EP (16.7%), LP + UMB + EP (16%), LNP + UMA + ENP (11.3%), LNP + UMB + ENP (5.3%), LNP + UMA + EP (3.3%), LNP + UMB + EP (2%), LNP + UM0 + EP (0.7%), and LNP + UM0 + ENP (0.7%). Sex, BMI, and age did not affect the distribution of metabotypes or MCs. Multivariate analysis (MaAslin2) revealed genera differentially present in individual metabotypes and MCs. Network analysis (MENA) showed the taxa acting as module hubs and connectors. Compositional and functional profiling, alpha and beta diversities, topological network features, and GM modulation by the nutraceutical differed depending on whether the entire cohort or each MC was considered. The nutraceutical did not change the composition of LP + UMA + EP (the most robust GM with the most associated functions) but increased its network connectors. This pioneering approach, joining GM's compositional, functional, and network features in polyphenol metabolism, paves the way for identifying personalized GM-targeted strategies to improve polyphenol health benefits.

Fragment merging approach for the design of thiazole/thiazolidine clubbed pyrazoline derivatives as anti-inflammatory agents: Synthesis, biopharmacological evaluation and molecular modeling studies

Fragment merging approach was applied for the design of thiazole/thiazolidinone clubbed pyrazoline derivatives 5a-e, 6a-c, 7 and 10a-d as dual COX-2 and 5-LOX inhibitors. Compounds 5a, 6a, and 6b were the most potent and COX-2 selective inhibitors (IC50= 0.03-0.06 μM, SI = 282.7-472.9) with high activity against 5-LOX (IC50 = 4.36-4.86 μM), while compounds 5b and 10a were active and selective 5-LOX inhibitors with IC50 = 2.43 and 1.58 μM, respectively. In vivo assay and histopathological examination for most active candidate 6a revealed significant decrease in inflammation with higher safety profile in comparison to standard drugs. Compound 6a exhibited the same orientation and binding interactions as the reference COX-2 and 5-LOX inhibitors (celecoxib and quercetin, respectively). Consequently, compound 6a has been identified as a potential lead for further optimization and the development of safe and effective anti-inflammatory drugs.

Evaluating the inhibitory activity of ferrocenyl Schiff bases derivatives on 5-lipoxygenase: Computational and biological studies

In the search for new 5-LOX inhibitors, two ferrocenyl Schiff base complexes functionalized with catechol ((ƞ5-(E)-C5H4-NCH-3,4-benzodiol)Fe(ƞ5-C5H5) (3a)) and vanillin ((ƞ5-(E)-C5H4-NCH-3-methoxy-4-phenol)Fe(ƞ5-C5H5) (3b)) were obtained. Complexes 3a and 3b were biologically evaluated as 5-LOX inhibitors showed potent inhibition compared to their organic analogs (2a and 2b) and known commercial inhibitors, with IC50 = 0.17 ± 0.05 μM for (3a) and 0.73 ± 0.06 μM for (3b) demonstrated a highly inhibitory and potent effect against 5-LOX due to the incorporation of the ferrocenyl fragment. Molecular dynamic studies showed a preferential orientation of the ferrocenyl fragment toward the non-heme iron of 5-LOX, which, together with electrochemical and in-vitro studies, allowed us to propose a competitive redox deactivation mechanism mediated by water, where Fe(III)-enzyme can be reduced by the ferrocenyl fragment. An Epa/IC50 relationship was observed, and the stability of the Schiff bases was evaluated by SWV in the biological medium, observing that the hydrolysis does not affect the high potency of the complexes, making them interesting alternatives for pharmacological applications.

Lipoxygenase inhibitory synthetic derivatives of methyl gallate regulate gene expressions of COX-2 and cytokines to reduce animal model arthritis

Mammalian lipoxygenases (LOXs) are involved in the biosynthesis of mediators of anaphylactic reactions and have been implicated in cell maturation, the pathogenesis of bronchial asthma, atherosclerosis, rheumatoid arthritis, cardiovascular diseases, Alzheimer's disease and osteoporosis. Hence LOX inhibition in chronic conditions can lead to reducing the disease progression, which can be a good target for treating these diseases. The present study deals with designing methyl gallate derivatives and their anti-inflammatory effect by in silico, in vitro and in vivo methods. Designed derivatives were docked against LOX enzyme, and molecular dynamic simulations were carried out. Following the synthesis of derivatives, in vitro LOX inhibition assay, enzyme kinetics and fluorescence quenching studies were performed. One of the derivatives of methyl gallate (MGSD 1) was demonstrated as an anti-inflammatory agent for the treatment of rheumatoid arthritis in the animal model. Amelioration of Freund's complete adjuvant (FCA)-induced arthritis by methyl gallate and its derivative with a concentration of 10-40 mg.kg-1 has been assessed in vivo in a 28-day-long study. TNF-α and COX-2 gene expression were also studied. Methyl gallate synthetic derivatives (MGSDs) inhibited LOX with an IC50 of 100 nM, 304 nM, and 226 nM for MGSD 1, MGSD 2, and MGSD 3, respectively. Fluorescence quenching methods also prove their binding characteristics, and 200 ns simulations studies showed that the RMSDs for the entire complex were less than 2.8 Å. The in vivo results showed that methyl gallate was required approximately five times diclofenac for the same level of effect, and the synthesised (MGSD 1) compound required only approximately 1/12 of diclofenac for the same level of effect in in-vivo studies. The preeminent expression of COX-2 and TNF-α genes was significantly decreased after the treatment of the methyl gallate derivative. Hence, the in vivo results showed that the referenced synthetic derivative might have more arthritis-reducing properties than the parent compound methyl gallate and is more potent than the standard drug diclofenac, with no apparent induced toxicity.

An integrated approach to the structural characterization, long-term toxicological and anti-inflammatory evaluation of Pterospermum rubiginosum bark extract

ETHNOPHARMACOLOGICAL RELEVANCE OF STUDY

Pterospermum rubiginosum is an evergreen plant in Western Ghats, India, used by traditional tribal healers due to its excellent biological potential for treating inflammation and pain relief procedures. The bark extract is also consumed to relieve the inflammatory changes at the bone fractured site. The traditional medicinal plant in India have to be characterized for its diverse phytochemical moieties, its interactive multiple target sites, and to reveal the hidden molecular mechanism behind the biological potency.

AIM OF THE STUDY

The study focussed on plant material characterization, computational analysis (prediction study), toxicological screening (In vivo), and anti-inflammatory evaluation of P. rubiginosum methanolic bark extracts (PRME) in LPS-induced RAW 264.7 cells.

MATERIALS AND METHODS

The pure compound isolation of PRME and their biological interactions were used to predict the bioactive components, molecular targets, and molecular pathways of PRME in inhibiting inflammatory mediators. The anti-inflammatory effects of PRME extract were evaluated in the lipopolysaccharide (LPS)-induced RAW264.7 macrophage cell model. The toxicity evaluation of PRME was performed in healthy 30 Sprague-Dawley experimental rats, were randomly divided into five groups for toxicological evaluation for 90 days. The tissue levels of oxidative stress and organ toxicity markers were measured using the ELISA method. Nuclear magnetic resonance spectroscopy (NMR) was performed to characterize the bioactive molecules.

RESULTS

Structural characterization revealed the presence of vanillic acid, 4-O-methyl gallic acid, E-resveratrol, gallocatechin, 4'-O-methyl gallocatechin, and catechin. Molecular docking of NF-kB exhibited significant interactions with vanillic acid and 4-O-methyl gallic acid with binding energy -351.159 Kcal/Mol and -326.5505 Kcal/Mol, respectively. The PRME-treated animals showed an increase in total GPx and antioxidant levels (SOD and catalase). Histopathological examination revealed no variation in the liver, renal and splenic tissue's cellular pattern. PRME inhibited the pro-inflammatory parameters (IL-1β, IL-6, and TNF-α) in LPS-induced RAW 264.7 cells. The protein level of TNF-α and NF-kB protein expression study brought out a notable reduction and exhibited a good correlation with the gene expression study.

CONCLUSION

The current study establishes the therapeutic potential of PRME as an effective inhibitory agent against LPS-activated RAW 264.7 cells induced inflammatory mediators. Long-term toxicity evaluation on SD rats confirmed the non-toxic nature of PRME up to 250mg/body weight for 3 months.

Functional Characterization of Transgenic Mice Overexpressing Human 15-Lipoxygenase-1 (ALOX15) under the Control of the aP2 Promoter

Arachidonic acid lipoxygenases (ALOX) have been implicated in the pathogenesis of inflammatory, hyperproliferative, neurodegenerative, and metabolic diseases, but the physiological function of ALOX15 still remains a matter of discussion. To contribute to this discussion, we created transgenic mice (aP2-ALOX15 mice) expressing human ALOX15 under the control of the aP2 (adipocyte fatty acid binding protein 2) promoter, which directs expression of the transgene to mesenchymal cells. Fluorescence in situ hybridization and whole-genome sequencing indicated transgene insertion into the E1-2 region of chromosome 2. The transgene was highly expressed in adipocytes, bone marrow cells, and peritoneal macrophages, and ex vivo activity assays proved the catalytic activity of the transgenic enzyme. LC-MS/MS-based plasma oxylipidome analyses of the aP2-ALOX15 mice suggested in vivo activity of the transgenic enzyme. The aP2-ALOX15 mice were viable, could reproduce normally, and did not show major phenotypic alterations when compared with wildtype control animals. However, they exhibited gender-specific differences with wildtype controls when their body-weight kinetics were evaluated during adolescence and early adulthood. The aP2-ALOX15 mice characterized here can now be used for gain-of-function studies evaluating the biological role of ALOX15 in adipose tissue and hematopoietic cells.

Classic Phytochemical Antioxidant and Lipoxygenase Inhibitor, Nordihydroguaiaretic Acid, Activates Phospholipase D through Oxidant Signaling and Tyrosine Phosphorylation Leading to Cytotoxicity in Lung Vascular Endothelial Cells

Nordihydroguaiaretic acid (NDGA), a dicatechol and phytochemical polyphenolic antioxidant and an established inhibitor of human arachidonic acid (AA) 5-lipoxygenase (LOX) and 15-LOX, is widely used to ascertain the role of LOXs in vascular endothelial cell (EC) function. As the modulatory effect of NDGA on phospholipase D (PLD), an important lipid signaling enzyme in ECs, thus far has not been reported, here we have investigated the modulation of PLD activity and its regulation by NDGA in the bovine pulmonary artery ECs (BPAECs). NDGA induced the activation of PLD (phosphatidic acid formation) in cells in a dose- and time-dependent fashion that was significantly attenuated by iron chelator and antioxidants. NDGA induced the formation of reactive oxygen species (ROS) in cells in a dose- and time-dependent manner as evidenced from fluorescence microscopy and fluorimetry of ROS and electron paramagnetic resonance spectroscopy of oxygen radicals. Also, NDGA caused a dose-dependent loss of intracellular glutathione (GSH) in BPAECs. Protein tyrosine kinase (PTyK)-specific inhibitors significantly attenuated NDGA-induced PLD activation in BPAECs. NDGA also induced a dose- and time-dependent phosphorylation of tyrosine in proteins in cells. NDGA caused in situ translocation and relocalization of both PLD₁ and PLD₂ isoforms, in a time-dependent fashion. Cyclooxygenase (COX) inhibitors were ineffective in attenuating NDGA-induced PLD activation in BPAECs, thus ruling out the activation of COXs by NDGA. NDGA inhibited the AA-LOX activity and leukotriene C₄ (LTC₄) formation in cells. On the other hand, the 5-LOX-specific inhibitors, 5, 8, 11, 14-eicosatetraynoic acid and kaempferol, were ineffective in activating PLD in BPAECs. Antioxidants and PTyK-specific inhibitors effectively attenuated NDGA cytotoxicity in BPAECs. The PLD-specific inhibitor, 5-fluoro-2-indolyl deschlorohalopemide (FIPI), significantly attenuated and protected against the NDGA-induced PLD activation and cytotoxicity in BPAECs. For the first time, these results demonstrated that NDGA, the classic phytochemical polyphenolic antioxidant and LOX inhibitor, activated PLD causing cytotoxicity in ECs through upstream oxidant signaling and protein tyrosine phosphorylation.

Neuroprotective Potentials of Flavonoids: Experimental Studies and Mechanisms of Action

Neurological and neurodegenerative diseases, particularly those related to aging, are on the rise, but drug therapies are rarely curative. Functional disorders and the organic degeneration of nervous tissue often have complex causes, in which phenomena of oxidative stress, inflammation and cytotoxicity are intertwined. For these reasons, the search for natural substances that can slow down or counteract these pathologies has increased rapidly over the last two decades. In this paper, studies on the neuroprotective effects of flavonoids (especially the two most widely used, hesperidin and quercetin) on animal models of depression, neurotoxicity, Alzheimer's disease (AD) and Parkinson's disease are reviewed. The literature on these topics amounts to a few hundred publications on in vitro and in vivo models (notably in rodents) and provides us with a very detailed picture of the action mechanisms and targets of these substances. These include the decrease in enzymes that produce reactive oxygen and ferroptosis, the inhibition of mono-amine oxidases, the stimulation of the Nrf2/ARE system, the induction of brain-derived neurotrophic factor production and, in the case of AD, the prevention of amyloid-beta aggregation. The inhibition of neuroinflammatory processes has been documented as a decrease in cytokine formation (mainly TNF-alpha and IL-1beta) by microglia and astrocytes, by modulating a number of regulatory proteins such as Nf-kB and NLRP3/inflammasome. Although clinical trials on humans are still scarce, preclinical studies allow us to consider hesperidin, quercetin, and other flavonoids as very interesting and safe dietary molecules to be further investigated as complementary treatments in order to prevent neurodegenerative diseases or to moderate their deleterious effects.

A Scoping Review of the Use of Pioglitazone in the Treatment of Temporo-Mandibular Joint Arthritis

Thiazolidinediones (TZDs) are a group of diabetes medications currently being investigated for anti-arthritis effectiveness, one of which is pioglitazone. The purpose of this scoping review is to evaluate the potential use of pioglitazone in the treatment of temporomandibular joint (TMJ) arthritis. The criteria of eligibility were studies with the diagnosis of arthritis and pioglitazone treatment with a change in any inflammation index as an outcome. Of the 1169 records initially identified following the selection process, two animal studies and four clinical studies were included in the review. Improvements from the baseline were observed in each treatment group for each inflammation indicator. The results of the animal studies on the temporomandibular joints and on patients with rheumatoid and psoriatic arthritis indicate that the drug in question may have potential to treat arthritis, including within the temporomandibular joint.

Anti-Inflammatory Activity of Olive Oil Polyphenols-The Role of Oleacein and Its Metabolites

The anti-inflammatory potential of oleacein, the main polyphenolic compound found in olive oil, and its main metabolites were characterized by their effects on RAW 264.7 macrophages challenged with lipopolysaccharide (LPS), and by their ability to inhibit enzymes of the arachidonic acid metabolism with a key role in the synthesis of pro-inflammatory lipid mediators. Oleacein at 12.5 µM significantly decreased the amount of L-citrulline and ^●NO generated by LPS-stimulated macrophages. Hydroxytyrosol, hydroxytyrosol acetate and hydroxytyrosol acetate sulfate were also able to reduce the cellular amount of ^●NO, although to a lesser extent. In contrast, hydroxytyrosol glucuronide and sulfate did not show detectable effects. Oleacein was also able to inhibit the coupled PLA₂ + 5-LOX enzyme system (IC₅₀ = 16.11 µM), as well as the 5-LOX enzyme (IC₅₀ = 45.02 µM). Although with lower activity, both hydroxytyrosol and hydroxytyrosol acetate were also capable of inhibiting these enzymes at a concentration of 100 µM. None of the other tested metabolites showed a capacity to inhibit these enzymes. In contrast, all compounds, including glucuronides and sulfate metabolites, showed a remarkable capacity to inhibit both cyclooxygenase isoforms, COX-1 and COX-2, with IC₅₀ values lower than 3 µM. Therefore, oleacein and its metabolites have the ability to modulate ^●NO- and arachidonic acid-dependent inflammatory cascades, contributing to the anti-inflammatory activity associated with olive oil polyphenols.

Modifiable Innate Biology within the Gut–Brain Axis for Alzheimer’s Disease

Alzheimer’s disease (AD) is a prototypical inflammation-associated loss of cognitive function, with approximately 90% of the AD burden associated with invading myeloid cells controlling the function of the resident microglia. This indicates that the immune microenvironment has a pivotal role in the pathogenesis of the disease. Multiple peripheral stimuli, conditioned by complex and varied interactions between signals that stem at the intestinal level and neuroimmune processes, are involved in the progression and severity of AD. Conceivably, the targeting of critical innate immune signals and cells is achievable, influencing immune and metabolic health within the gut–brain axis. Considerable progress has been made, modulating many different metabolic and immune alterations that can drive AD development. However, non-pharmacological strategies targeting immunometabolic processes affecting neuroinflammation in AD treatment remain general and, at this point, are applied to all patients regardless of disease features. Despite these possibilities, improved knowledge of the relative contribution of the different innate immune cells and molecules comprising the chronically inflamed brain network to AD pathogenesis, and elucidation of the network hierarchy, are needed for planning potent preventive and/or therapeutic interventions. Moreover, an integrative perspective addressing transdisciplinary fields can significantly contribute to molecular pathological epidemiology, improving the health and quality of life of AD patients. This review is intended to gather modifiable immunometabolic processes based on their importance in the prevention and management of AD.

Calcium signaling in neurodevelopment and pathophysiology of autism spectrum disorders

BACKGROUND

Autism spectrum disorder (ASD) covers a group of neurodevelopmental disorders with complex genetic background. Several genetic mutations, epigenetic alterations, copy number variations and single nucleotide polymorphisms have been reported that cause ASD or modify its phenotype. Among signaling pathways that influence pathogenesis of ASD, calcium signaling has a prominent effect.

METHODS

We searched PubMed and Google Scholar databases with key words "Calcium signaling" and "Autism spectrum disorder".

CONCLUSION

This type of signaling has essential roles in the cell physiology. Endoplasmic reticulum and mitochondria are the key organelles involved in this signaling. It is vastly accepted that organellar disorders intensely influence the central nervous system (CNS). Several lines of evidence indicate alterations in the function of calcium channels in polygenic disorders affecting CNS. In the current review, we describe the role of calcium signaling in normal function of CNS and pathophysiology of ASD.

The Tower of Babel of Pharma-Food Study on Extra Virgin Olive Oil Polyphenols

Much research has been conducted to reveal the functional properties of extra virgin olive oil polyphenols on human health once EVOO is consumed regularly as part of a balanced diet, as in the Mediterranean lifestyle. Despite the huge variety of research conducted, only one effect of EVOO polyphenols has been formally approved by EFSA as a health claim. This is probably because EFSA’s scientific opinion is entrusted to scientific expertise about food and medical sciences, which adopt very different investigative methods and experimental languages, generating a gap in the scientific communication that is essential for the enhancement of the potentially useful effects of EVOO polyphenols on health. Through the model of the Tower of Babel, we propose a challenge for science communication, capable of disrupting the barriers between different scientific areas and building bridges through transparent data analysis from the different investigative methodologies at each stage of health benefits assessment. The goal of this work is the strategic, distinctive, and cost-effective integration of interdisciplinary experiences and technologies into a highly harmonious workflow, organized to build a factual understanding that translates, because of trade, into health benefits for buyers, promoting EVOOs as having certified health benefits, not just as condiments.

Curcumin and Wnt/β‑catenin signaling in exudative age‑related macular degeneration (Review)

Curcumin is a natural product widely used due to its pharmacological effects. Nevertheless, only a limited number of studies concerning the effects of curcumin on exudative age‑related macular degeneration (AMD) is currently available. Since ophthalmic diseases, including exudative AMD, have a marked impact on public health, the prevention and therapy of ophthalmic disorders remain of increasing concern. Exudative AMD is characterized by choroidal neovascularization (CNV) invading the subretinal space, ultimately enhancing exudation and hemorrhaging. The exudative AMD subtype corresponds to 10 to 15% of cases of macular degeneration; however, the occurrence of this subtype has been reported as the major cause of vision loss and blindness, with the occurrence of CNV being responsible for 80% of the cases with vision loss. In CNV increased expression of VEGF has been observed, stimulated by the overactivation of Wnt/β‑catenin signaling pathway. The stimulation of the Wnt/β‑catenin signaling pathway is responsible for the activation of several cellular mechanisms, simultaneously enhancing inflammation, oxidative stress and angiogenesis in numerous diseases, including ophthalmic disorders. Some studies have previously demonstrated the possible advantage of the use of curcumin for the inhibition of Wnt/β‑catenin signaling. In the present review article, the different mechanisms of curcumin are described concerning its effects on oxidative stress, inflammation and angiogenesis in exudative AMD, by interacting with Wnt/β‑catenin signaling.

Anti-Inflammatory and Antiproliferative Properties of Sweet Cherry Phenolic-Rich Extracts

Cherries have largely been investigated due to their high content in phenolics in order to fully explore their health-promoting properties. Therefore, this work aimed to assess, for the first time, the anti-inflammatory potential of phenolic-targeted fractions of the Saco cherry, using RAW 264.7 macrophages stimulated with lipopolysaccharide. Additionally, the cytotoxic effects on gastric adenocarcinoma (AGS), neuroblastoma (SH-SY5Y) and normal human dermal fibroblast (NHDF) cells were evaluated, as well as the ability to protect these cellular models against induced oxidative stress. The obtained data revealed that cherry fractions can interfere with cellular nitric oxide (NO) levels by capturing NO radicals and decreasing inducible nitric oxide synthase and cyclooxygenase-2 expression. Furthermore, it was observed that all cherry fractions exhibited dose-dependent cytotoxicity against AGS cells, presenting cytotoxic selectivity for these cancer cells when compared to SH-SY5Y and NHDF cells. Regarding their capacity to protect cancer cells against oxidative injury, in most assays, the total cherry extract was the most effective. Overall, this study reinforces the idea that sweet cherries can be incorporated into new pharmaceutical products, smart foods and nutraceuticals.

Caffeic acid attenuates irradiation-induced hematopoietic stem cell apoptosis through inhibiting mitochondrial damage

Hematopoietic stem cells (HSCs) are sensitive to ionizing radiation (IR) damage, and its injury is the primary cause of bone marrow (BM) hematopoietic failure and even death after exposure to a certain dose of IR. However, the underlying mechanisms remain incompletely understood. Here we show that mitochondrial oxidative damage, which is characterized by mitochondrial reactive oxygen species overproduction, mitochondrial membrane potential reduction and mitochondrial permeability transition pore opening, is rapidly induced in both human and mouse HSCs and directly accelerates HSC apoptosis after IR exposure. Mechanistically, 5-lipoxygenase (5-LOX) is induced by IR exposure and contributes to IR-induced mitochondrial oxidative damage through inducing lipid peroxidation. Intriguingly, a natural antioxidant, caffeic acid (CA), can attenuate IR-induced HSC apoptosis through suppressing 5-LOX-mediated mitochondrial oxidative damage, thus protecting against BM hematopoietic failure after IR exposure. These findings uncover a critical role for mitochondria in IR-induced HSC injury and highlight the therapeutic potential of CA in BM hematopoietic failure induced by IR.