Resolvins and omega three polyunsaturated fatty acids: Clinical implications in inflammatory diseases and cancer

Targeting cyclooxygenase-2 for chemoprevention of inflammation-associated intestinal carcinogenesis: An update

Mounting evidence from preclinical and clinical studies suggests that persistent inflammation functions as a driving force in the journey to cancer. Cyclooxygenase-2 (COX-2) is a key enzyme involved in inflammatory signaling. While being transiently upregulated upon inflammatory stimuli, COX-2 has been found to be consistently overexpressed in human colorectal cancer and several other malignancies. The association between chronic inflammation and cancer has been revisited: cancer can arise when inflammation fails to resolve. Besides its proinflammatory functions, COX-2 also catalyzes the production of pro-resolving as well as anti-inflammatory metabolites from polyunsaturated fatty acids. This may account for the side effects caused by long term use of some COX-2 inhibitory drugs during the cancer chemopreventive trials. This review summarizes the latest findings highlighting the dual functions of COX-2 in the context of its implications in the development, maintenance, and progression of cancer.

Dietary lipid supplementation alleviated the impacts of polystyrene nanoplastic exposure in Litopenaeus vannamei

The widespread occurrence of nanoplastic (NP) pollution in the environment is a growing concern, and its presence poses a potential threat to cultured aquatic animals. Previously, we found that NPs can significantly affect the lipid metabolism of shrimp. However, relevant reports about the effects of increasing dietary lipid levels on NP toxicity are lacking. Therefore, we explored the effects of dietary supplementation with different lipid levels on the growth and lipid metabolism of Pacific white shrimp (Litopenaeus vannamei). We cultured L. vannamei at three dietary lipid levels (3 %, 6 %, and 9 %) and three NP concentrations (0, 1, and 3 mg/L) for 2 months. We evaluated the effects of lipid levels on growth indexes, hepatopancreas morphological structure, lipid metabolism-related enzyme activity, and gene expression of the shrimp. The results showed that as lipid intake increased, the survival rate, body weight growth rate, and hepatosomatic ratio of the shrimp increased while the feed conversion rate decreased. Additionally, the crude protein and crude lipid contents increased, whereas the moisture and ash contents did not change much. We found that the morphological structure of the hepatopancreas was seriously damaged in the 3 mg/L NPs and 3 % dietary lipid group. Finally, lipid metabolism-related enzyme activities and gene expression levels increased with increased dietary lipid levels. Together, these results suggest that increasing dietary lipid content can improve shrimp growth and alleviate lipid metabolism disorders caused by NPs. This study is the first to show that nutrition regulation can alleviate the toxicity of NPs, and it provides a theoretical basis for the green and healthy culture of L. vannamei.

Effects of Bioactive Dietary Components on Changes in Lipid and Liver Parameters in Women after Bariatric Surgery and Procedures

Excess adipose tissue, as well as its distribution, correlates strongly with disorders of lipid and liver parameters and chronic inflammation. The pathophysiology of metabolic diseases caused by obesity is associated with the dysfunction of visceral adipose tissue. Effective and alternative interventions such as the Bioenteric Intragastric Balloon and bariatric surgeries such as the Roux-en-Y gastric bypass. The aim of this study was to assess the effect of modifying the recommended standard weight loss diet after bariatric surgery and procedures on reducing chronic inflammation in overweight patients. In the study, bioactive anti-inflammatory dietary components were used supportively. Changes in the concentrations of lipid parameters, liver parameters, antioxidant enzymes, cytokines, and chemokines were demonstrated. The enrichment of the diet, after bariatric surgery, with the addition of n-3 EFAs(Essential Fatty Acids), bioflavonoids, vitamins, and synbiotics resulted in higher weight losses in the patients in the study with a simultaneous reduction in parameters indicating liver dysfunction.

CMKLR1 senses chemerin/resolvin E1 to control adipose thermogenesis and modulate metabolic homeostasis

Induction of beige fat for thermogenesis is a potential therapy to improve homeostasis against obesity. β3-adrenoceptor (β3-AR), a type of G protein-coupled receptor (GPCR), is believed to mediate the thermogenesis of brown fat in mice. However, β3-AR has low expression in human adipose tissue, precluding its activation as a standalone clinical modality. This study aimed at identifying a potential GPCR target to induce beige fat. We found that chemerin chemokine-like receptor 1 (CMKLR1), one of the novel GPCRs, mediated the development of beige fat via its two ligands, chemerin and resolvin E1 (RvE1). The RvE1 levels were decreased in the obese mice, and RvE1 treatment led to a substantial improvement in obese features and augmented beige fat markers. Inversely, despite sharing the same receptor as RvE1, the chemerin levels were increased in obesogenic conditions, and chemerin treatment led to an augmented obese phenotype and a decline of beige fat markers. Moreover, RvE1 and chemerin induced or restrained the development of beige fat, respectively, via the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. We further showed that RvE1 and chemerin regulated mTORC1 signaling differentially by forming hydrogen bonds with different binding sites of CMKLR1. In conclusion, our study showed that RvE1 and chemerin affected metabolic homeostasis differentially, suggesting that selectively modulating CMKLR1 may be a potential therapeutic target for restoring metabolic homeostasis.

Crosstalk between P2Y receptors and cyclooxygenase activity in inflammation and tissue repair

The role of extracellular nucleotides as modulators of inflammation and cell stress is well established. One of the main actions of these molecules is mediated by the activation of purinergic receptors (P2) of the plasma membrane. P2 receptors can be classified according to two different structural families: P2X ionotropic ion channel receptors, and P2Y metabotropic G protein-coupled receptors. During inflammation, damaged cells release nucleotides and purinergic signaling occurs along the temporal pattern of the synthesis of pro-inflammatory and pro-resolving mediators by myeloid and lymphoid cells. In macrophages under pro-inflammatory conditions, the expression and activity of cyclooxygenase 2 significantly increases and enhances the circulating levels of prostaglandin E2 (PGE2), which exerts its effects both through specific plasma membrane receptors (EP1-EP4) and by activation of intracellular targets. Here we review the mechanisms involved in the crosstalk between PGE2 and P2Y receptors on macrophages, which is dependent on several isoforms of protein kinase C and protein kinase D1. Due to this crosstalk, a P2Y-dependent increase in calcium is blunted by PGE2 whereas, under these conditions, macrophages exhibit reduced migratory capacity along with enhanced phagocytosis, which contributes to the modulation of the inflammatory response and tissue repair.

The impact of Resolvin E1 on bone regeneration in critical-sized calvarial defects of rat model-A gene expression and micro-CT analysis

OBJECTIVE

To investigate, in vivo, the effect of local application of Resolvin E1 (RvE1) on the bone regeneration of critical-size defects (CSDs) in Wistar rats utilizing gene expression and micro-computed tomographic (micro-CT) analysis.

BACKGROUND

The inflammation-resolving actions of RvE1 are well established. The molecular mechanism of its bone-regenerative actions has been of significant interest in recent years; however, there is limited information regarding the same.

MATERIALS AND METHODS

Thirty Wistar rats with a 5 mm induced critical-size calvarial defect were randomly allocated into four groups: no treatment/negative control (n = 5), treatment using bovine bone grafts/positive control (n = 5), treatment using local delivery of RvE1 (n = 11) and treatment using RvE1 mixed with bovine bone graft (n = 9). After 4 weeks, RNA isolation, complementary DNA synthesis and real-time polymerase chain reaction were used for genetic expression of alkaline phosphatase (ALP), osteocalcin (OCN) and osteopontin (OPN). The rats were sacrificed after 12 weeks and micro-CT imaging was performed to analyse the characteristics of the newly formed bone (NFB). The data were analysed using ANOVA and the least significant difference tests (α ≤ .05).

RESULTS

The RvE1 + bovine graft group had statistically highest mean NFB (20.75 ± 2.67 mm3 ) compared to other groups (p < .001). Similarly, RvE1 + bovine graft group also demonstrated statistically highest mean genetic expression of ALP (31.71 ± 2.97; p = .008) and OPN (34.78 ± 3.62; p < .001) compared to negative control and RvE1 groups.

CONCLUSION

Resolvin E1 with adjunct bovine bone graft demonstrated an enhanced bone regeneration compared to RvE1 or bovine graft alone in the calvarial defect of Wistar rats.

Molecular Mechanisms Associated with the Inhibitory Role of Long Chain n-3 PUFA in Colorectal Cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related death in the world. Multiple evidence suggests that there is an association between excess fat consumption and the risk of CRC. The long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential for human health, and both in vitro and in vivo studies have shown that these fatty acids can prevent CRC development through various molecular mechanisms. These include the modulation of arachidonic acid (AA) derived prostaglandin synthesis, alteration of growth signaling pathways, arrest of the cell cycle, induction of cell apoptosis, suppression of angiogenesis and modulation of inflammatory response. Human clinical studies found that LC n-3 PUFA combined with chemotherapeutic agents can improve the efficacy of treatment and reduce the dosage of chemotherapy and associated side effects. In this review, we discuss comprehensively the anti-cancer effects of LC n-3 PUFA on CRC, with a main focus on the underlying molecular mechanisms.

Synaptamide modulates glial and neurotransmitter activity in the spinal cord during neuropathic pain

N-docosahexaenoylethanolamine, or synaptamide, is an endogenous metabolite of docosahexaenoic acid that is known for synaptogenic and neurogenic effects. In our previous studies we have shown that synaptamide attenuates neuropathic pain, facilitates remyelination, and reduces neuroinflammation after the chronic constriction injury (CCI) of the sciatic nerve in rats. In the current study, we show that daily synaptamide administration (4 mg/kg/day) within 14 days post-surgery: (1) decreases micro- and astroglia activity in the dorsal and ventral horns of the lumbar spinal cord; (2) modulates pro-inflammatory (IL1β, IL6) and anti-inflammatory (IL4, IL10) cytokine level in the serum and spinal cord; (3) leads to a rise in synaptamide and anandamide concentration in the spinal cord; (4) enhances IL10, CD206 and N-acylethanolamine-hydrolyzing acid amidase synthesis in macrophage cell culture following LPS-induced inflammation. Thus, the ability of synaptamide to modulate glial and cytokine activity indicates its potential for implementation in the treatment peripheral nerve injury.

Change to Mixed-Lipid Emulsion From Soybean Oil-Based Lipid Emulsion in Pediatric Patients

Importance

Critically ill pediatric patients often require parenteral nutrition (PN) in the intensive care unit (ICU). Literature suggests mixed lipid emulsions (LE) with soybean oil reduction strategies may improve outcomes.

Objective

To examine the association of a hospital-wide switch to a mixed-lipid formula (4-OLE) with pediatric outcomes.

Design, Setting, and Participants

Retrospective cohort study at a large US academic referral center. Pediatric patients aged 1 month to 17 years requiring parenteral nutrition from May 2016 to September 2019 were included. Data were analyzed from October 2020 to February 2023.

Exposure

In 2017, Duke University Health System fully converted to a soybean oil/MCT/olive/fish oil lipid (4-OLE) from pure soybean oil-based LE in pediatric patients. Pediatric patients before the change (Intralipid [IL] group) were compared with patients after (4-OLE group).

Main Outcomes and Measures

Clinical outcomes were compared between treatment periods via multivariable regression models. The primary outcome was hospital length of stay (LOS). Fourteen secondary outcomes included hospital mortality of any cause, 30-day or 90-day readmission, pneumonia, urinary tract infections (UTIs), total caloric delivery, and liver function tests (aspartate aminotransferase, alanine transaminase, alkaline phosphatase, and total bilirubin).

Results

A total of 684 children dependent on PN were identified (342 were critically ill), with 30% (206 children) in the preswitch (IL) period and 70% (478 children) in the postswitch (4-OLE) period; 123 were male (59.7%). In comparing IL vs 4-OLE, there was a significant difference in median (IQR) age (4.0 [1.2-13.0] vs 3.0 [0.8-9.0] years, respectively; P = .04), without difference in body mass index or baseline comorbidities except for significant differences in cancer diagnosis (26 patients in the IL group [12.6%] vs 29 patients in the 4-OLE group [6.1%]; P = .004) and chronic obstructive pulmonary disease (24 patients in the IL group [11.7%] vs 30 patients in the 4-OLE group [6.3%]; P = .02). In the all children cohort, 4-OLE was associated with shorter hospital LOS (IRR, 0.81; 95% CI, 0.05-0.78), and reduced UTI risk (OR, 0.33; 95% CI, 0.18-0.64). In the ICU cohort, 4-OLE was associated with shorter hospital LOS (IRR, 0.81; 95% CI, 0.78-0.83), and reduced UTI risk (OR, 0.23; 95% CI, 0.11-0.51). Other secondary outcomes were not significant.

Conclusions and Relevance

In this observational study of clinical outcomes among children dependent on PN, a switch to 4-OLE in a large academic hospital was associated with a significant decrease in hospital LOS in ICU and non-ICU patients. These findings suggest switching to a soy-LE sparing strategy using 4-OLE is feasible, safe, and associated with improved clinical outcomes in pediatric PN patients.

Can Dietary n-3 Polyunsaturated Fatty Acids Affect Apelin and Resolvin in Testis and Sperm of Male Rabbits?

Apelin and other novel adipokines have been associated with normal and pathological reproductive conditions in humans and animals. In this paper, we used a rabbit model to investigate if apelin and resolvin (RvD1) in testis and sperm are associated with the oxidative status of semen and serum testosterone of rabbits fed different diets enriched with flaxseed (alpha-linolenic acid, ALA) or with fish oil (eicosapentaenoic acid, EPA, docosapentaenoic acid, DPAn-3, and docosahexaenoic acid, DHA). Apelin and RvD1 were detected by ELISA and apelin and the apelin receptor by immunofluorescence. Increased levels of apelin in testes from both enriched diets were shown, particularly in the interstitial tissue of the FLAX group. The FLAX diet enhanced serum testosterone, and both enriched diets showed higher levels of malondialdehyde and RvD1 in the testis. In ejaculated sperm, apelin and its receptor were localized in the entire tail of the control and both treated groups. The ryanodine receptor was investigated in rabbit testis; the fluorescent signal was increased in mature elongated spermatids of the FLAX group. In conclusion, this data seems to indicate that FLAX increases the amount of apelin in testis, suggesting an involvement of this adipokine in male reproduction and probably a role in the resolution of the inflammatory status.

The Role of Specialized Pro-Resolving Lipid Mediators in Inflammation-Induced Carcinogenesis

Cancer is a process involving cell mutation, increased proliferation, invasion, and metastasis. Over the years, this condition has represented one of the most concerning health problems worldwide due to its significant morbidity and mortality. At present, the incidence of cancer continues to grow exponentially. Thus, it is imperative to open new avenues in cancer research to understand the molecular changes driving DNA transformation, cell-to-cell interaction derangements, and immune system surveillance decay. In this regard, evidence supports the relationship between chronic inflammation and cancer. In light of this, a group of bioactive lipids derived from polyunsaturated fatty acids (PUFAs) may have a position as novel anti-inflammatory molecules known as the specialized pro-resolving mediators (SPMs), a group of pro-resolutive inflammation agents that could improve the anti-tumor immunity. These molecules have the potential role of chemopreventive and therapeutic agents for various cancer types, and their effects have been documented in the scientific literature. Thus, this review objective centers around understanding the effect of SPMs on carcinogenesis and their potential therapeutic effect.

Anti-Inflammatory Activity of Synaptamide in the Peripheral Nervous System in a Model of Sciatic Nerve Injury

N-docosahexaenoylethanolamine (DHEA), or synaptamide, is an endogenous metabolite of docosahexaenoic acid (DHA) that exhibits synaptogenic and neurogenic effects. In our previous studies, synaptamide administration inhibited the neuropathic pain-like behavior and reduced inflammation in the central nervous system following sciatic nerve injury. In the present study, we examine the effect of synaptamide on the peripheral nervous system in a neuropathic pain condition. The dynamics of ionized calcium-binding adapter molecule 1 (iba-1), CD68, CD163, myelin basic protein, and the production of interleukin 1β and 6 within the sciatic nerve, as well as the neuro-glial index and the activity of iba-1, CD163, glial fibrillary acidic protein (GFAP), neuronal NO synthase (nNOS), substance P (SP), activating transcription factor 3 (ATF3) in the dorsal root ganglia (DRG), are studied. According to our results, synaptamide treatment (4 mg/kg/day) (1) decreases the weight-bearing deficit after nerve trauma; (2) enhances the remyelination process in the sciatic nerve; (3) shows anti-inflammatory properties in the peripheral nervous system; (4) decreases the neuro-glial index and GFAP immunoreactivity in the DRG; (5) inhibits nNOS- and SP-ergic activity in the DRG, which might contribute to neuropathic pain attenuation. In general, the current study demonstrates the complex effect of synaptamide on nerve injury, which indicates its high potential for neuropathic pain management.

An update on animal models of intervertebral disc degeneration and low back pain: Exploring the potential of artificial intelligence to improve research analysis and development of prospective therapeutics

Animal models have been invaluable in the identification of molecular events occurring in and contributing to intervertebral disc (IVD) degeneration and important therapeutic targets have been identified. Some outstanding animal models (murine, ovine, chondrodystrophoid canine) have been identified with their own strengths and weaknesses. The llama/alpaca, horse and kangaroo have emerged as new large species for IVD studies, and only time will tell if they will surpass the utility of existing models. The complexity of IVD degeneration poses difficulties in the selection of the most appropriate molecular target of many potential candidates, to focus on in the formulation of strategies to effect disc repair and regeneration. It may well be that many therapeutic objectives should be targeted simultaneously to effect a favorable outcome in human IVD degeneration. Use of animal models in isolation will not allow resolution of this complex issue and a paradigm shift and adoption of new methodologies is required to provide the next step forward in the determination of an effective repairative strategy for the IVD. AI has improved the accuracy and assessment of spinal imaging supporting clinical diagnostics and research efforts to better understand IVD degeneration and its treatment. Implementation of AI in the evaluation of histology data has improved the usefulness of a popular murine IVD model and could also be used in an ovine histopathological grading scheme that has been used to quantify degenerative IVD changes and stem cell mediated regeneration. These models are also attractive candidates for the evaluation of novel anti-oxidant compounds that counter inflammatory conditions in degenerate IVDs and promote IVD regeneration. Some of these compounds also have pain-relieving properties. AI has facilitated development of facial recognition pain assessment in animal IVD models offering the possibility of correlating the potential pain alleviating properties of some of these compounds with IVD regeneration.

Intervertebral disc degeneration and how it leads to low back pain

The purpose of this review was to evaluate data generated by animal models of intervertebral disc (IVD) degeneration published in the last decade and show how this has made invaluable contributions to the identification of molecular events occurring in and contributing to pain generation. IVD degeneration and associated spinal pain is a complex multifactorial process, its complexity poses difficulties in the selection of the most appropriate therapeutic target to focus on of many potential candidates in the formulation of strategies to alleviate pain perception and to effect disc repair and regeneration and the prevention of associated neuropathic and nociceptive pain. Nerve ingrowth and increased numbers of nociceptors and mechanoreceptors in the degenerate IVD are mechanically stimulated in the biomechanically incompetent abnormally loaded degenerate IVD leading to increased generation of low back pain. Maintenance of a healthy IVD is, thus, an important preventative measure that warrants further investigation to preclude the generation of low back pain. Recent studies with growth and differentiation factor 6 in IVD puncture and multi-level IVD degeneration models and a rat xenograft radiculopathy pain model have shown it has considerable potential in the prevention of further deterioration in degenerate IVDs, has regenerative properties that promote recovery of normal IVD architectural functional organization and inhibits the generation of inflammatory mediators that lead to disc degeneration and the generation of low back pain. Human clinical trials are warranted and eagerly anticipated with this compound to assess its efficacy in the treatment of IVD degeneration and the prevention of the generation of low back pain.

Lipid Metabolic Alterations in KRAS Mutant Tumors: Unmasking New Vulnerabilities for Cancer Therapy

KRAS is one of the most commonly mutated genes, an event that leads to development of highly aggressive and resistant to any type of available therapy tumors. Mutated KRAS drives a complex network of lipid metabolic rearrangements to support the adaptation of cancer cells to harsh environmental conditions and ensure their survival. Because there has been only a little success in the continuous efforts of effectively targeting KRAS-driven tumors, it is of outmost importance to delineate the exact mechanisms of how they get rewired, leading to this distinctive phenotype. Therefore, the aim of this review is to summarize the available data acquired over the last years with regard to the lipid metabolic regulation of KRAS-driven tumors and elucidate their specific characteristics in an attempt to unravel novel therapeutic targets.

Safety assessment of fish oil green extraction and in vivo acute toxicity evaluation

Sardine co-products can represent an interesting source of bioactive compounds, such as polyunsaturated fatty acids and in particular omega-3. This study aimed to investigate extraction of oil from sardine co-products by enzymatic hydrolysis using two proteases: commercial Alcalase and protease Bb from a local fungal strain (P2) of Beauveria bassiana, which overproduces proteases. Despite a higher degree of hydrolysis (41.34%) than Alcalase (24.28%), protease Bb allowed the extraction of approximately the same oil content. Resulting oil from both processes had the same fatty acid profile. Interestingly, the all-produced oil displayed an attractive w6/w3 ratio, an indicator of nutritional quality, of the order of 0.16. The safety of the generated oils was also assessed by treating two groups of Wistar rats with the fish oil administered by oral gavage at the doses (30 mg/kg and 300 mg/kg body weight) for 14 days using olive oil as a vehicle. Compared to controls used, both treated groups showed no statistically significant differences. Consequently, the acute oral toxicity evaluated by hematological, biochemical, and histological studies showed the safety of the oil generated using B. bassiana protease.

Hospital change to mixed lipid emulsion from soybean oil-based lipid emulsion for parenteral nutrition in hospitalized and critically ill adults improves outcomes: a pre-post-comparative study

INTRODUCTION

Early data suggest use of a mixed lipid emulsion (LE) with a soybean oil reduction strategy in parenteral nutrition (PN) may improve clinical outcomes. Duke University Hospital made a full switch to a Soybean oil/MCT/Olive/Fish Oil lipid (4-OLE) from pure soybean oil-based LE (Intralipid, Baxter Inc) in May 2017. Since 4-OLE has limited evidence related to its effects on clinical outcome parameters in US hospitals, evidence for clinical benefits of switching to 4-OLE is needed. Therefore, we examined the clinical utility of a hospital-wide switch to 4-OLE and its effect on patient outcomes.

METHODS

We conducted a single-center retrospective cohort study among adult patients (> 18 years) requiring PN from 2016 to 2019. Our primary exposure was treatment period (1-year pre-4-OLE switch versus 2-year post). We used multivariable regression models to examine our primary outcomes, the association of treatment period with hospital length of stay (LOS), and secondary outcomes liver function, infections, and ICU LOS. Analyses were stratified into critically ill and entire adult cohort.

RESULTS

We identified 1200 adults hospitalized patients. 28% of PN patients (n = 341) were treated pre-4-OLE switch and 72% post-4-OLE (n = 859). In the adult cohort, 4-OLE was associated with shorter hospital LOS (IRR 0.97, 95% CI 0.95-0.99, p = 0.039). The ICU cohort included 447 subjects, of which 25% (n = 110) were treated pre-4-OLE switch and 75% (n = 337) were post-switch. ICU patients receiving 4-OLE were associated with shorter hospital LOS (IRR 0.91, 95% CI 0.87-0.93, p < 0.0001), as well as a shorter ICU LOS (IRR 0.90, 95% CI 0.82-0.99, p = 0.036). 4-OLE ICU patients also had a significantly lower delta total bilirubin (- 1.6, 95% CI - 2.8 to - 0.2, p = 0.021) and reduced urinary tract infection (UTI) rates (OR 0.50, 95% CI 0.26-0.96, p = 0.038). There were no associations in AST, ALT, or total bilirubin in ICU and all adult patients.

CONCLUSION

4-OLE was successfully implemented and reduced soybean oil LE exposure in a large academic hospital setting. The introduction of 4-OLE was associated with reduced LOS, UTI rates, and mitigated hepatic dysfunction in critically ill patients. Overall, these findings prove a switch to a soybean oil-LE sparing strategy using 4-OLE is feasible and safe and is associated with improved clinical outcomes in adult PN patients.

Growth State-Dependent Expression of Arachidonate Lipoxygenases in the Human Endothelial Cell Line EA.hy926

Endothelial cells regulate vascular homeostasis through the secretion of various paracrine molecules, including bioactive lipids, but little is known regarding the enzymes responsible for generating these lipids under either physiological or pathophysiological conditions. Arachidonate lipoxygenase (ALOX) expression was therefore investigated in confluent and nonconfluent EA.h926 endothelial cells, which represent the normal quiescent and proliferative states, respectively. mRNAs for ALOX15, ALOX15B, and ALOXE3 were detected in EA.hy926 cells, with the highest levels present in confluent cells compared to nonconfluent cells. In contrast, ALOX5, ALOX12, and ALOX12B mRNAs were not detected. At the protein level, only ALOX15B and ALOXE3 were detected but only in confluent cells. ALOXE3 was also observed in confluent human umbilical artery endothelial cells (HUAEC), indicating that its expression, although previously unreported, may be a general feature of endothelial cells. Exposure to laminar flow further increased ALOXE3 levels in EA.hy926 cells and HUAECs. The evidence obtained in this study indicates that proliferative status and shear stress are both important factors that mediate endothelial ALOX gene expression. The presence of ALOX15B and ALOXE3 exclusively in quiescent human endothelial cells suggests their activity likely contributes to the maintenance of a healthy endothelium.

The probiotic Lactobacillus rhamnosus GG (LGG) restrains the angiogenic potential of colorectal carcinoma cells by activating a pro-resolving program via formyl peptide receptor 1

Formyl peptide receptors (FPR1, FPR2 and FPR3) are innate immune sensors of pathogen and commensal bacteria and have a role in colonic mucosa homeostasis. We identified FPR1 as a tumour suppressor in gastric cancer cells due to its ability to sustain an inflammation resolution response with antiangiogenic potential. Here, we investigate whether FPR1 exerts similar functions in colorectal carcinoma (CRC) cells. Since it has been shown that the commensal bacterium Lactobacillus rhamnosus GG (LGG) can promote intestinal epithelial homeostasis through FPR1, we explored the possibility that it could induce proresolving and antiangiogenic effects in CRC cells. We demonstrated that pharmacologic inhibition or genetic deletion of FPR1 in CRC cells caused a reduction of proresolving mediators and a consequent upregulation of angiogenic factors. The activation of FPR1 mediates opposite effects. Proresolving, antiangiogenic and homeostatic functions were also observed upon treatment of CRC cells with supernatant of LGG culture, but not of other lactic acid or nonprobiotic bacteria (i.e. Bifidobacterium bifidum or Escherichia coli). These activities of LGG are dependent on FPR1 expression and on the subsequent MAPK signalling activation. Thus, the innate immune receptor FPR1 could be a regulator of the balance between microbiota, inflammation and cancer in CRC models.

Link between Omega 3 Fatty Acids Carried by Lipoproteins and Breast Cancer Severity

According to the International Agency for Research on Cancer (IARC) more than 10% of cancers can be explained by inadequate diet and excess body weight. Breast cancer is the most common cancer affecting women. The goal of our study is to clarify the relationship between ω3 fatty acids (FA) carried by different lipoproteins and breast cancer (BC) severity, according to two approaches: through clinic-biological data and through in vitro breast cancer cell models. The clinical study has been performed in sera from a cohort of BC women (n = 140, ICO, France) whose tumors differed by their hormone receptors status (HR− for tumors negative for estrogen receptors and progesterone receptors, HR+ for tumors positive for either estrogen receptors or progesterone receptors) and the level of proliferation markers (Ki-67 ≤ 20% Prolif− and Ki-67 ≥ 30% Prolif+). Lipids and ω3FA have been quantified in whole serum and in apoB-containing lipoproteins (Non-HDL) or free of it (HDL). Differences between Prolif− and Prolif+ were compared by Wilcoxon test in each sub-group HR+ and HR−. Results are expressed as median [25th−75th percentile]. Plasma cholesterol, triglycerides, HDL-cholesterol and Non-HDL cholesterol did not differ between Prolif− and Prolif+ sub-groups of HR− and HR+ patients. Plasma EPA and DHA concentrations did not differ either. In the HR− group, the distribution of EPA and DHA between HDL and Non-HDL differed significantly, as assessed by a higher ratio between the FA concentration in Non-HDL and HDL in Prolif− vs. Prolif+ patients (0.20 [0.15−0.36] vs. 0.04 [0.02−0.08], p = 0.0001 for EPA and 0.08 [0.04−0.10] vs. 0.04 [0.01−0.07], p = 0.04 for DHA). In this HR− group, a significant increase in Non-HDL EPA concentration was also observed in Prolif− vs. Prolif+ (0.18 [0.13−0.40] vs. 0.05 [0.02−0.07], p = 0.001). A relative enrichment on Non-HDL in EPA and DHA was also observed in Prolif− patients vs. Prolif+ patients, as assessed by a higher molar ratio between FA and apoB (0.12 [0.09−0.18] vs. 0.02 [0.01−0.05], p < 0.0001 for EPA and 1.00 [0.73−1.69 vs. 0.52 [0.14−1.08], p = 0.04 for DHA). These data were partly confirmed by an in vitro approach of proliferation of isolated lipoproteins containing EPA and DHA on MDA-MB-231 (HR−) and MCF-7 (HR+) cell models. Indeed, among all the studied fractions, only the correlation between the EPA concentration of Non-HDL was confirmed in vitro, although with borderline statistical significance (p = 0.07), in MDA-MB-231 cells. Non-HDL DHA, in the same cells model was significantly correlated to proliferation (p = 0.04). This preliminary study suggests a protective effect on breast cancer proliferation of EPA and DHA carried by apo B-containing lipoproteins (Non-HDL), limited to HR− tumors.

Reducing neuroinflammation via therapeutic compounds and lifestyle to prevent or delay progression of Parkinson's disease

Parkinson's disease (PD) is the second most common age-associated neurodegenerative disorder and is characterised by progressive loss of dopamine neurons in the substantia nigra. Peripheral immune cell infiltration and activation of microglia and astrocytes are observed in PD, a process called neuroinflammation. Neuroinflammation is a fundamental response to protect the brain but, when chronic, it triggers neuronal damage. In the last decade, central and peripheral inflammation were suggested to occur at the prodromal stage of PD, sustained throughout disease progression, and may play a significant role in the pathology. Understanding the pathological mechanisms of PD has been a high priority in research, primarily to find effective treatments once symptoms are present. Evidence indicates that early life exposure to neuroinflammation as a consequence of life events, environmental or behaviour factors such as exposure to infections, pollution or a high fat diet increase the risk of developing PD. Many studies show healthy habits and products that decrease neuroinflammation also reduce the risk of PD. Here, we aim to stimulate discussion about the role of neuroinflammation in PD onset and progression. We highlight that reducing neuroinflammation throughout the lifespan is critical for preventing idiopathic PD, and present epidemiological studies that detail risk and protective factors. It is possible that introducing lifestyle changes that reduce neuroinflammation at the time of PD diagnosis may slow symptom progression. Finally, we discuss compounds and therapeutics to treat the neuroinflammation associated with PD.

Production of 8,11-dihydroxy fatty acids from oleic and palmitoleic acids by Escherichia coli cells expressing variant 6,8-linoleate diol synthases from Penicillium oxalicum

Recombinant Escherichia coli cells expressing 8,11-linoleate diol synthase (LDS) from Penicillium chrysogenum convert oleic and palmitoleic acids to 8-hydroperoxy-9(Z)-octadecenoic acid (HPOME) and 8-hydroperoxy-9(Z)-hexadecenoic acid (HPHME) only, respectively. However, recombinant E. coli cells expressing Q889A variant 6,8-LDS from Penicillium oxalicum as an 8,11-LDS converted oleic and palmitoleic acids to 8,11-dihydroxy-9(Z)-octadecenoic acid (DiHOME) and 8,11-dihydroxy-9(Z)-hexadecenoic acid (DiHHME), respectively, which were identified using LC-MS/MS analysis. To select suitable variants for producing these compounds, position 889 of 6,8-LDS from P. oxalicum was substituted with other amino acids, and recombinant E. coli cells expressing Q889L and Q889A variants were chosen as the best biocatalysts for producing 8,11-DiHOME and 8,11-DiHHME, respectively. The optimal conditions for producing 8,11-DiHOME or 8,11-DiHHME using cells expressing Q889L or Q889A variant 6,8-LDS were pH 6.5 and 30 °C with 5% (v/v) dimethyl sulfoxide (DMSO), 60 g L^-1 cells, and 10 g L^-1 oleic acid or 7.5 g L^-1 palmitoleic acid, respectively. Under these conditions, 10.7 g L^-1 8,11-DiHOME and 8.1 g L^-1 8,11-DiHHME were produced for 1.5 h with molar yields of 96.4 and 96.2% and productivities of 7.1 and 5.4 g L^-1  h^-1 , respectively. The molar yields and concentrations of 8,11-DiHOME and 8,11-DiHHME were highest among those of other reported DiHOMEs and DiHHMEs. To the best of our knowledge, this is the first quantitative production of 8,11-DiHOME and 8,11-DiHHME. This article is protected by copyright. All rights reserved.

Dietary PUFAs drive diverse system-level changes in lipid metabolism

OBJECTIVE

Polyunsaturated fatty acid (PUFA) supplements have been trialled as a treatment for a number of conditions and produced a variety of results. This variety is ascribed to the supplements, that often comprise a mixture of fatty acids, and to different effects in different organs. In this study, we tested the hypothesis that the supplementation of individual PUFAs has system-level effects that are dependent on the molecular structure of the PUFA.

METHODS

We undertook a network analysis using Lipid Traffic Analysis to identify both local and system-level changes in lipid metabolism using publicly available lipidomics data from a mouse model of supplementation with FA(20:4n-6), FA(20:5n-3), and FA(22:6n-3); arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid, respectively. Lipid Traffic Analysis is a new computational/bioinformatics tool that uses the spatial distribution of lipids to pinpoint changes or differences in control of metabolism, thereby suggesting mechanistic reasons for differences in observed lipid metabolism.

RESULTS

There was strong evidence for changes to lipid metabolism driven by and dependent on the structure of the supplemented PUFA. Phosphatidylcholine and triglycerides showed a change in the variety more than the total number of variables, whereas phosphatidylethanolamine and phosphatidylinositol showed considerable change in both which variables and the number of them, in a highly PUFA-dependent manner. There was also evidence for changes to the endogenous biosynthesis of fatty acids and to both the elongation and desaturation of fatty acids.

CONCLUSIONS

These results show that the full biological impact of PUFA supplementation is far wider than any single-organ effect and implies that supplementation and dosing with PUFAs require a system-level assessment.

Molecular Pharmacology of Inflammation Resolution in Atherosclerosis

Atherosclerosis is one of the most important problems of modern medicine as it is the leading cause of hospitalizations, disability, and mortality. The key role in the development and progression of atherosclerosis is the imbalance between the activation of inflammation in the vascular wall and the mechanisms of its control. The resolution of inflammation is the most important physiological mechanism that is impaired in atherosclerosis. The resolution of inflammation has complex, not fully known mechanisms, in which lipid mediators derived from polyunsaturated fatty acids (PUFAs) play an important role. Specialized pro-resolving mediators (SPMs) represent a group of substances that carry out inflammation resolution and may play an important role in the pathogenesis of atherosclerosis. SPMs include lipoxins, resolvins, maresins, and protectins, which are formed from PUFAs and regulate many processes related to the active resolution of inflammation. Given the physiological importance of these substances, studies examining the possibility of pharmacological effects on inflammation resolution are of interest.

Interconnections between Inflammageing and Immunosenescence during Ageing

Acute inflammation is a physiological response to injury or infection, with a cascade of steps that ultimately lead to the recruitment of immune cells to clear invading pathogens and heal wounds. However, chronic inflammation arising from the continued presence of the initial trigger, or the dysfunction of signalling and/or effector pathways, is harmful to health. While successful ageing in older adults, including centenarians, is associated with low levels of inflammation, elevated inflammation increases the risk of poor health and death. Hence inflammation has been described as one of seven pillars of ageing. Age-associated sterile, chronic, and low-grade inflammation is commonly termed inflammageing-it is not simply a consequence of increasing chronological age, but is also a marker of biological ageing, multimorbidity, and mortality risk. While inflammageing was initially thought to be caused by "continuous antigenic load and stress", reports from the last two decades describe a much more complex phenomenon also involving cellular senescence and the ageing of the immune system. In this review, we explore some of the main sources and consequences of inflammageing in the context of immunosenescence and highlight potential interventions. In particular, we assess the contribution of cellular senescence to age-associated inflammation, identify patterns of pro- and anti-inflammatory markers characteristic of inflammageing, describe alterations in the ageing immune system that lead to elevated inflammation, and finally assess the ways that diet, exercise, and pharmacological interventions can reduce inflammageing and thus, improve later life health.

Dietary influence on modulation of Helicoverpa armigera oral secretion composition leading to differential regulation of tomato plant defense

Little is known about how different plant-based diets influence the insect herbivores' oral secretion (OS) composition and eventually the plant defense responses. We analyzed the OS composition of the generalist Lepidopteran insect, Helicoverpa armigera feeding on the host plant tomato (OS_H), non-host plant capsicum (OS_NH), and artificial diet (OS_AD) using Liquid Chromatography-Quadrupole Time of Flight Mass Spectrometry. Higher numbers and levels of alkaloids and terpenoids were observed in OS_H and OS_NH, respectively while OS_AD was rich in phospholipids. Interestingly, treatment of H. armigera OS_AD, OS_H and OS_NH on wounded tomato leaves showed differential expression of (i) genes involved in JA and SA biosynthesis and their responsive genes, and (ii) biosynthetic pathway genes of chlorogenic acid (CGA) and trehalose, which exhibited increased accumulation along with several other plant defensive metabolites. Specifically, high levels of CGA were detected after OS_H and OS_NH treatments in tomato leaves. There was higher expression of the genes involved in phenylpropanoid biosynthesis, which may lead to the increased accumulation of CGA and related metabolites. In the insect bioassay, CGA significantly inhibited H. armigera larval growth. Our results underline the differential accumulation of plant and insect OS metabolites and identified potential plant metabolite(s) affecting insect growth and development.

Resolvins as a Treatment Modality in Experimental Periodontitis: A Systematic Review of Preclinical Studies

This systematic review aimed to assess scientific data of existing literature to identify the efficacy of resolvins (Rv) in the treatment of periodontitis. The electronic databases, Web of Science (WOS), Medline/PubMed, The Cochrane Library, Scopus, and Saudi digital library (SDL), were searched for eligible studies in the field of periodontics. A thorough analysis of the retrieved literature provided five articles that were assessed and included in this systematic review. The quality of these studies was assessed by updated Essential Animal Research: Reporting of In-Vivo Experiments (ARRIVE) guidelines. The five included studies were published between 2005 and 2018 and investigated resolvins as a treatment approach in experimental periodontitis of animals. Among the study animals employed, New Zealand white rabbits were used in three studies, Wistar rats and Albino mice in two studies, respectively. Four studies have evaluated eicosapentaenoic acid-derived RvE1, and one study evaluated docosahexaenoic acid-derived RvD2. Oral-topical application of Rv was followed in four studies, and intra-peritoneal Rv injection was administered in one study. The study duration in these studies have ranged between 4-12 weeks, and the Rv dose was between 0.1 μg to 0.5 μg. One study evaluated the influence of RvE1 topical application on both the prevention and treatment of experimental periodontitis. Resolvins (RvE1 and RvD2) have been studied in periodontitis-induced animal models to assess their potential role in periodontal inflammation resolution. There are promising preclinical data of using resolvins as a treatment modality in experimental periodontitis. Resolvins have been demonstrated to inhibit the destructive inflammatory process and alveolar bone loss in laboratory-induced periodontitis under controlled experimental conditions.

Plasma Sphingosine-1-Phosphate Levels Are Associated with Progression of Estrogen Receptor-Positive Breast Cancer

Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.

Development of allergic conjunctivitis induced by Acanthamoeba excretory-secretory protein and the effect of resolvin D1 on treatment

PURPOSE

To evaluate whether allergic conjunctivitis (AC) could be induced by Acanthamoeba excretory-secretory protein (ESP) and analyze the therapeutic effect of resolvin (Rv) D1 and antiallergic agents.

METHODS

Human conjunctival epithelial cells (HCVCs) were treated with 10 µg/well of ESP, and Th2 cytokines were measured using real-time PCR. C57BL/6 mice were treated with 10 µg/5 µL of ESP after sensitization, and conjunctivas isolated from the mice were stained with hematoxylin and eosin (H&E) for the analysis of eosinophils and periodic acid-Schiff (PAS) for the analysis of goblet cells. Cytokine levels in the eye-draining lymph nodes (dLNs) and spleens were measured using the enzyme-linked immunosorbent assay (ELISA). Then, the treatment effects of RvD1 and the antiallergic agents (olopatadine, bepotastine, and alcaftadine) on the HCVCs, mouse conjunctivas, dLNs, and spleens were assessed.

RESULTS

Th2 cytokines were increased in the ESP-treated conjunctival cells. Mouse conjunctivas treated with ESP showed significant infiltration of eosinophils and goblet cells, and the dLN and spleen exhibited increased IL-4, IL-5 and IL-13 levels. All findings were significantly decreased upon treatment with RvD1 and the antiallergic agents.

CONCLUSIONS

Acanthamoeba could be used to establish an animal model of AC, which could be effectively treated with RvD1 or topical antiallergic agents.

Molecular insights into lipoxygenases for biocatalytic synthesis of diverse lipid mediators

Oxylipins derived mainly from C20- and C22-polyunsaturated fatty acids (PUFAs), termed lipid mediators (LMs), are essential signalling messengers involved in human physiological responses associated with homeostasis and healing process for infection and inflammation. Some LMs involved in the resolution of inflammation and infection are termed specialized pro-resolving mediators (SPMs), which are generated by human M2 macrophages or polymorphonuclear leukocytes and have the potential to protect and treat hosts from bacterial and viral infections by phagocytosis activation. Lipoxygenases (LOXs) biosynthesize regio- and stereoselective LMs. Thus, understanding the regio- and stereoselectivities of LOXs for PUFAs at a molecular level is important for the biocatalytic synthesis of diverse LMs. Here, we elucidate the catalytic mechanisms and discuss regio- and stereoselectivities and their changes of LOXs determined by insertion direction and position of the substrate and oxygen at a molecular level for the biosynthesis of diverse human LMs. Recently, the biocatalytic synthesis of PUFAs to human LMs or analogues has been conducted using microbial LOXs. Such microbial LOXs involved in the biosynthesis of LMs are expected to exert significantly higher activity and stability than human LOXs. Diverse regio- and stereoselective LOXs can be obtained from microorganisms, which represent a wealth of genomic sources. We reconstruct the biosynthetic pathways of LOX-catalyzed LMs in humans and other organisms. Furthermore, we suggest the effective methods of biocatalytic synthesis of diverse human LMs from PUFAs or glucose by using microbial LOXs, increasing the stability and activity of LOXs, combining the reactions of LOXs, and constructing metabolic pathways.

Role of pyroptosis in diabetic retinopathy and its therapeutic implications

Pyroptosis has recently been established as a term of programmed-inflammatory cell death. Pyroptosis is mainly divided into two molecular signaling pathways, including caspase-1-dependent canonical and caspase-4/5/11-dependent non-canonical inflammasome pathways. Extensive investigations have reported inflammasome activation facilitates the maturation and secretion of the inflammatory factors interleukin-1β/18 (IL-1β/18), cleavage of gasdermin D (GSDMD), and leading to the stimulation of pyroptosis-mediated cell death. Furthermore, accumulating studies report NLRP3 inflammasome activation plays a significant role in triggering the pyroptosis-mediated cell death and promotes the pathogenesis of diabetic retinopathy (DR). Our current review elaborates on the molecular mechanisms of pyroptosis-signaling pathways and their potential roles in the pathogenesis and impact of DR development. We also emphasize several investigational molecules regulating key steps in pyroptotic-cell death to create new comprehensions and findings to explore the pathogenesis of DR advancement. Our narrative review concisely suggests these potential pharmacological agents could be promising therapies to treat and manage DR in the future.

Dietary and Protective Factors to Halt or Mitigate Progression of Autoimmunity, COVID-19 and Its Associated Metabolic Diseases

COVID-19 is without any doubt the worst pandemic we have faced since the H1N1 virus outbreak. Even if vaccination against SARS-CoV-2 infection is becoming increasingly available, a more feasible approach for COVID-19 prevention and therapy is still needed. Evidence of a pathological link between metabolic diseases and severe forms of COVID-19 has stimulated critical reflection and new considerations. In particular, an abnormal immune response observed in certain patients with SARS-CoV-2 infection suggested possible common predisposing risk factors with autoimmune diseases such as Type 1 Diabetes (T1D). Correct supplementation with dietary factors may be key to preventing and counteracting both the underlying metabolic impairment and the complications of COVID-19. A set of agents may inhibit the cytokine storm and hypercoagulability that characterize severe COVID-19 infection: vitamin D3, omega-3 polyunsaturated fatty acids, polyphenols like pterostilbene, polydatin and honokiol, which can activate anti-inflammatory and antioxidant sirtuins pathways, quercetin, vitamin C, zinc, melatonin, lactoferrin and glutathione. These agents could be highly beneficial for subjects who have altered immune responses. In this review, we discuss the antiviral and metabolic effects of these dietary factors and propose their combination for potential applications in the prevention and treatment of COVID-19. Rigorous studies will be fundamental for validating preventive and therapeutic protocols that could be of assistance to mitigate disease progression following SARS-CoV-2 infection.

Can N-3 polyunsaturated fatty acids be considered a potential adjuvant therapy for COVID-19-associated cardiovascular complications?

Coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has currently led to a global pandemic with millions of confirmed and increasing cases around the world. The novel SARS-CoV-2 not only affects the lungs causing severe acute respiratory dysfunction but also leads to significant dysfunction in multiple organs and physiological systems including the cardiovascular system. A plethora of studies have shown the viral infection triggers an exaggerated immune response, hypercoagulation and oxidative stress, which contribute significantly to poor cardiovascular outcomes observed in COVID-19 patients. To date, there are no approved vaccines or therapies for COVID-19. Accordingly, cardiovascular protective and supportive therapies are urgent and necessary to the overall prognosis of COVID-19 patients. Accumulating literature has demonstrated the beneficial effects of n-3 polyunsaturated fatty acids (n-3 PUFA) toward the cardiovascular system, which include ameliorating uncontrolled inflammatory reactions, reduced oxidative stress and mitigating coagulopathy. Moreover, it has been demonstrated the n-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are precursors to a group of potent bioactive lipid mediators, generated endogenously, which mediate many of the beneficial effects attributed to their parent compounds. Considering the favorable safety profile for n-3 PUFAs and their metabolites, it is reasonable to consider n-3 PUFAs as potential adjuvant therapies for the clinical management of COVID-19 patients. In this article, we provide an overview of the pathogenesis of cardiovascular complications secondary to COVID-19 and focus on the mechanisms that may contribute to the likely benefits of n-3 PUFAs and their metabolites.

Oxidation of polyunsaturated fatty acids to produce lipid mediators

The chemistry, biochemistry, pharmacology and molecular biology of oxylipins (defined as a family of oxygenated natural products that are formed from unsaturated fatty acids by pathways involving at least one step of dioxygen-dependent oxidation) are complex and occasionally contradictory subjects that continue to develop at an extraordinarily rapid rate. The term includes docosanoids (e.g. protectins, resolvins and maresins, or specialized pro-resolving mediators), eicosanoids and octadecanoids and plant oxylipins, which are derived from either the omega-6 (n-6) or the omega-3 (n-3) families of polyunsaturated fatty acids. For example, the term eicosanoid is used to embrace those biologically active lipid mediators that are derived from C₂₀ fatty acids, and include prostaglandins, thromboxanes, leukotrienes, hydroxyeicosatetraenoic acids and related oxygenated derivatives. The key enzymes for the production of prostanoids are prostaglandin endoperoxide H synthases (cyclo-oxygenases), while lipoxygenases and oxidases of the cytochrome P450 family produce numerous other metabolites. In plants, the lipoxygenase pathway from C₁₈ polyunsaturated fatty acids yields a variety of important products, especially the jasmonates, which have some comparable structural features and functions. Related oxylipins are produced by non-enzymic means (isoprostanes), while fatty acid esters of hydroxy fatty acids (FAHFA) are now being considered together with the oxylipins from a functional perspective. In all kingdoms of life, oxylipins usually act as lipid mediators through specific receptors, have short half-lives and have functions in innumerable biological contexts.

Attenuation of acute and chronic inflammation using compounds derived from plants

The appearance of excessive inflammatory activity is associated with onset of many disease states. Such non-productive responses are often the basis of the mortality consequent to incurring numerous disorders. The current outbreak of coronavirus disease 2019 caused by the virus "severe acute respiratory syndrome coronavirus 2" is a striking reflection of the inadequacy of current medical science to adequately address this issue. The usefulness of a range of materials of botanical origin in the attenuation of both chronic and acute inflammatory responses to various disease stressors is described. The properties of preparations of plant-based origin often parallel those of synthesized pharmacologics, but differ from them in some key respects. These differences can lead to more traditional preparations having distinct therapeutic advantages but also a number of specific shortcomings. The strengths and weaknesses of these materials are objectively contrasted with that of a more orthodox pharmacological approach. Each of these emphases in style has specific advantages and they should not be considered as competitors, but rather as accomplices in combating adverse states involving derangement of immune function.

Long chain omega-3 fatty acids and their oxidized metabolites are associated with reduced prostate tumor growth

INTRODUCTION

Cancer has been associated with increased oxidative stress and deregulation of bioactive oxylipins derived from long-chain polyunsaturated fatty acids (LC-PUFA) like arachidonic acid (AA). There is a debate whether ω-3 LC-PUFA could promote or prevent prostate tumor growth through immune modulation and reduction of oxidative stress. Our aim was to study the association between enzymatically or non-enzymatically produced oxidized-LC-PUFA metabolites and tumor growth in an immune-competent eugonadal and castrated C57BL/6 male mice injected with TRAMP-C2 prostate tumor cells, fed with ω-3 or ω-6 LC-PUFA-rich diets.

MATERIALS AND METHODS

Tumor fatty acids were profiled by gas chromatography and 26 metabolites derived from either AA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were assessed by liquid chromatography-mass spectrometry.

RESULTS

The enriched ω-3 diet did not reduce oxidative stress overall in tumors but favored the formation of ω-3 rather than ω-6 derived isoprostanoids. We discovered that EPA and its oxidized-derivatives like F₃-isoprostanes and prostaglandin (PG)F_3α, were inversely correlated with tumor volume (spearman correlations and T-test, p<0.05). In contrast, F₂-isoprostanes, adrenic acid, docosapentaenoic acid (DPA_ω-6) and PGE₂ were positively correlated with tumor volume. Interestingly, F₄-neuroprostanes, PGD₂, PGF_2α, and thromboxane were specifically increased in TRAMP-C2 tumors of castrated mice compared to those of eugonadal mice.

DISCUSSION

Decreasing tumor growth under ω-3 diet could be attributed in part to increased levels of EPA and its oxidized-derivatives, a reduced level of pro-angiogenic PGE₂ and increased levels of F₄-neuroprostanes and resolvins content in tumors, suspected of having anti-proliferative and anti-inflammatory effects.

Effect of fish oil on oxidative stress markers in patients with probable Alzheimer´s disease

High intake of omega-3 fatty acids has been associated with synaptic plasticity, neurogenesis and memory in several experimental models. To assess the efficacy of fish oil supplementation on oxidative stress markers in patients diagnosed with probable Alzheimer´s disease (AD) we conducted a double blind, randomized, placebo controlled clinical trial. AD patients who met the inclusive criteria were given fish oil (containing 0.45 g eicosapentaenoic acid and 1 g docosahexaenoic acid) or placebo daily for 12 months. Oxidative stress markers [lipoperoxides, nitric oxide catabolites levels, oxidized/reduced glutathione ratio, and membrane fluidity] and fatty acid profile in erythrocytes were assessed at enrollment, and 6 and 12 months after the start of the testing period. At the end of the trial, in patients who received fish oil, we detected a decrease in the omega 6/omega 3 ratio in erythrocyte membrane phospholipids. This change was parallel with decreases in plasma levels of lipoperoxides and nitric oxide catabolites. Conversely, the ratio of reduced to oxidized glutathione was significantly increased. In addition, membrane fluidity was increased significantly in plasma membrane samples. In conclusion fish oil administration has a beneficial effect in decreasing the levels of oxidative stress markers and improving the membrane fluidity in plasma. El alto consumo de ácidos grasos omega-3 se asocia con la plasticidad sináptica, neurogénesis y memoria en varios modelos experimentales. Para evaluar la eficacia de la suplementación con aceite de pescado en los marcadores de estrés oxidativo en pacientes con diagnóstico de la enfermedad de Alzheimer (EA) probable realizamos un ensayo clínico doble ciego, aleatorizado, controlado con placebo. A los pacientes con la EA que cumplían los criterios de inclusión se les administró aceite de pescado (que contenía 0,45 g de ácido eicosapentaenoico y 1 g de ácido docosahexaenoico) o placebo diariamente durante 12 meses. Los marcadores de estrés oxidativo plasmático [niveles de lipoperóxidos y catabolitos del óxido nítrico, cociente de glutatión reducido a glutatiónoxidado) y fluidez de la membrana] y el perfil de ácidos grasos en los eritrocitos se evaluaron al inicio, 6 meses y alos 12 meses. Al final del ensayo, en pacientes que recibieron aceite de pescado detectamos una disminución en el cociente de ácidos grasos omega 6/omega 3 en los fosfolípidos de la membrana eritrocitaria. Este cambio ocurrió en paralelo a la disminución de los niveles plasmáticos de lipoperóxidos y catabolitos del óxido nítrico. Por el contrario, el cociente de glutatión reducido a glutatión oxidado se incrementó significativamente. Además, la fluidez de la membrana aumentó significativamente en las muestras analizadas. En conclusión, la administración de aceite de pescado tiene un efecto beneficioso al disminuir los niveles de marcadores de estrés oxidativo plasmático y mejorar la fluidez de la membrana plasmática.

Effects of Concurrent Omega-3 and Cranberry Juice Consumption Along with Standard Antibiotic Therapy on the Eradication of Helicobacter pylori, Gastrointestinal Symptoms, Some Serum Inflammatory and Oxidative Stress Markers in Adults with Helicobacter pylori Infection: A Study Protocol for a Randomized Controlled Trial

BACKGROUND

It seems alternative treatments such as antioxidant intervention and anti-inflammatory intervention adjuvant to antibiotic regimens may enhance cancer prevention approaches and decrease adverse side effects related to therapeutic antibiotic regimens. So, we will evaluate the effects of concurrent omega-3 and cranberry juice supplementation along with standard antibiotic therapy on the eradication of Helicobacter pylori, gastrointestinal symptoms, some serum inflammatory and oxidative stress markers in adults with HP infection.

METHODS

We will conduct a 4-week double-blinded randomized clinical trial. The subjects will be randomly stratified according to sex and BMI using a permuted block randomization procedure by Random Allocation Software (RAS). They will be assigned to one of the four study groups: (1) cranberry juice fortified with omega-3 Intervention (n=23), (2) cranberry juice intervention group (n=23), (3) placebo beverage fortified with omega-3 intervention group (n=23), and (4) placebo beverage intervention (control group) (n=23). All statistical analyses will be performed using IBM SPSS Statistics software.

DISCUSSION

A combination of alternative therapies may have a synergistic effect compared to a single approach. It could potentially be more effective in promoting the efficacy of standard antibiotic therapy in eradicating HP infection.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT20151128025274N3, www.irct.ir/trial/28997).

TRIAL STATUS

This study is in the early stages of sampling.

Significance of Omega-3 Fatty Acids in the Prophylaxis and Treatment after Spinal Cord Injury in Rodent Models

Polyunsaturated fatty acids (ω-3 acids, PUFAs) are essential components of cell membranes in all mammals. A multifactorial beneficial influence of ω-3 fatty acids on the health of humans and other mammals has been observed for many years. Therefore, ω-3 fatty acids and their function in the prophylaxis and treatment of various pathologies have been subjected to numerous studies. Regarding the documented therapeutic influence of ω-3 fatty acids on the nervous and immune systems, the aim of this paper is to present the current state of knowledge and the critical assessment of the role of ω-3 fatty acids in the prophylaxis and treatment of spinal cord injury (SCI) in rodent models. The prophylactic properties (pre-SCI) include the stabilization of neuron cell membranes, the reduction of the expression of inflammatory cytokines (IL-1β, TNF-α, IL-6, and KC/GRO/CINC), the improvement of local blood flow, reduced eicosanoid production, activation of protective intracellular transcription pathways (dependent on RXR, PPAR-α, Akt, and CREB), and increased concentration of lipids, glycogen, and oligosaccharides by neurons. On the other hand, the therapeutic properties (post-SCI) include the increased production of endogenous antioxidants such as carnosine and homocarnosine, the maintenance of elevated GSH concentrations at the site of injury, reduced concentrations of oxidative stress marker (MDA), autophagy improvement (via increasing the expression of LC3-II), and p38 MAPK expression reduction in the superficial dorsal horns (limiting the sensation of neuropathic pain). Paradoxically, despite the well-documented protective activity of ω-3 acids in rodents with SCI, the research does not offer an answer to the principal question of the optimal dose and treatment duration. Therefore, it is worth emphasizing the role of multicenter rodent studies with the implementation of standards which initially may even be based on arbitrary criteria. Additionally, basing on available research data, the authors of this paper make a careful attempt at referring some of the conclusions to the human population.

COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation

The novel coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has engulfed the world, affecting more than 180 countries. As a result, there has been considerable economic distress globally and a significant loss of life. Sadly, the vulnerable and immunocompromised in our societies seem to be more susceptible to severe COVID-19 complications. Global public health bodies and governments have ignited strategies and issued advisories on various handwashing and hygiene guidelines, social distancing strategies, and, in the most extreme cases, some countries have adopted "stay in place" or lockdown protocols to prevent COVID-19 spread. Notably, there are several significant risk factors for severe COVID-19 infection. These include the presence of poor nutritional status and pre-existing noncommunicable diseases (NCDs) such as diabetes mellitus, chronic lung diseases, cardiovascular diseases (CVD), obesity, and various other diseases that render the patient immunocompromised. These diseases are characterized by systemic inflammation, which may be a common feature of these NCDs, affecting patient outcomes against COVID-19. In this review, we discuss some of the anti-inflammatory therapies that are currently under investigation intended to dampen the cytokine storm of severe COVID-19 infections. Furthermore, nutritional status and the role of diet and lifestyle is considered, as it is known to affect patient outcomes in other severe infections and may play a role in COVID-19 infection. This review speculates the importance of nutrition as a mitigation strategy to support immune function amid the COVID-19 pandemic, identifying food groups and key nutrients of importance that may affect the outcomes of respiratory infections.

Molecular modeling and LC-MS-based metabolomics of a glutamine-valproic acid (Gln-VPA) derivative on HeLa cells

Glutaminase plays an important role in carcinogenesis and cancer cell growth. This biological target is interesting against cancer cells. Therefore, in this work, in silico [docking and molecular dynamics (MD) simulations] and in vitro methods (antiproliferative and LC-MS metabolomics) were employed to assay a hybrid compound derived from glutamine and valproic acid (Gln-VPA), which was compared with 6-diazo-5-oxo-L-norleucine (DON, a glutaminase inhibitor) and VPA (contained in Gln-VPA structure). Docking results from some snapshots retrieved from MD simulations show that glutaminase recognized Gln-VPA and DON. Additionally, Gln-VPA showed antiproliferative effects in HeLa cells and inhibited glutaminase activity. Finally, the LC-MS-based metabolomics studies on HeLa cells treated with either Gln-VPA (IC₆₀ = 8 mM) or DON (IC₅₀ = 3.5 mM) show different metabolomics behaviors, suggesting that they modulate different biological targets of the cell death mechanism. In conclusion, Gln-VPA is capable of interfering with more than one pharmacological target of cancer, making it an interesting drug that can be used to avoid multitherapy of classic anticancer drugs.

Integrated Transcriptomics, Metabolomics, and Lipidomics Profiling in Rat Lung, Blood, and Serum for Assessment of Laser Printer-Emitted Nanoparticle Inhalation Exposure-Induced Disease Risks

Laser printer-emitted nanoparticles (PEPs) generated from toners during printing represent one of the most common types of life cycle released particulate matter from nano-enabled products. Toxicological assessment of PEPs is therefore important for occupational and consumer health protection. Our group recently reported exposure to PEPs induces adverse cardiovascular responses including hypertension and arrythmia via monitoring left ventricular pressure and electrocardiogram in rats. This study employed genome-wide mRNA and miRNA profiling in rat lung and blood integrated with metabolomics and lipidomics profiling in rat serum to identify biomarkers for assessing PEPs-induced disease risks. Whole-body inhalation of PEPs perturbed transcriptional activities associated with cardiovascular dysfunction, metabolic syndrome, and neural disorders at every observed time point in both rat lung and blood during the 21 days of exposure. Furthermore, the systematic analysis revealed PEPs-induced transcriptomic changes linking to other disease risks in rats, including diabetes, congenital defects, auto-recessive disorders, physical deformation, and carcinogenesis. The results were also confirmed with global metabolomics profiling in rat serum. Among the validated metabolites and lipids, linoleic acid, arachidonic acid, docosahexanoic acid, and histidine showed significant variation in PEPs-exposed rat serum. Overall, the identified PEPs-induced dysregulated genes, molecular pathways and functions, and miRNA-mediated transcriptional activities provide important insights into the disease mechanisms. The discovered important mRNAs, miRNAs, lipids and metabolites may serve as candidate biomarkers for future occupational and medical surveillance studies. To the best of our knowledge, this is the first study systematically integrating in vivo, transcriptomics, metabolomics, and lipidomics to assess PEPs inhalation exposure-induced disease risks using a rat model.

Lyophilized extracts from vegetable flours as valuable alternatives to purified oxygenases for the synthesis of oxylipins

In this work, the whole aqueous extracts of soybean flour and oat flour have been used as valuable alternatives to purified oxygenase enzymes for the preparation of oxylipins derived from (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoic acid (EPA). The lipoxygenase activity in the aqueous extracts of soybean (Glycine max. L.) flour was monitored with linoleic acid as substrate and compared with the commercially available purified enzyme (LOX-1). Oat flour extracts (Avena sativa L.) were evaluated for their peroxygenase activity by comparing different enzyme preparations in the epoxidation of methyl oleate. It was found that lyophilization of the aqueous extracts from these vegetable flours offers advantages in terms of enzyme stability, reproducibility and applicability to preparative organic synthesis. The lyophilized enzyme preparations were tested for the oxyfunctionalization of EPA and the formed products were isolated in satisfactory yields. In the presence of lyophilized extract from soybean, EPA gave 15S-hydroxy-(5Z,8Z,11Z,13E,17Z)-eicosapentaenoic acid in enantiopure form as exclusive product. Peroxygenase from oat flour was less selective and catalyzed the formation of different epoxides of EPA. However, the biocatalyzed epoxidation of EPA under controlled conditions allowed to obtain optically active (17R,18S)-epoxy-(5Z,8Z,11Z,14Z)-eicosatetraenoic acid (65% ee) as the main monoepoxide, among the five possible ones.

The Evaluation of Potential Cytotoxic Effect of Different Proton Pump Inhibitors on Different Human Cancer Cell Lines

OBJECTIVE

To assess the differential cytotoxic activity of PPIs on different human cancer cell lines; namely A549 lung cancer, CACO-2 colorectal cancer, MCF-7 breast cancer, and PANC-1 pancreatic cancer, A375 skin melanoma.

METHODS

In this study, the five human cancer cell lines and human non-cancerous fibroblasts were treated with increasing concentration of PPIs Omeprazole (OMP), Esomeprazole (ESOM), and Lansoprazole (LANSO) (50-300μM), over 24h, 48h, and 72h. Cell viability was determined using 3-(4,5- Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and the IC50 values of PPIs were measured. The most sensitive cell line A375 was used for further investigation. The cytotoxic effects of LANSO on these cells were assessed using Annexin-V Propidium Iodide (AV-PI) flow cytometry. As of action mechanism; anti-inflammatory effects of each PPIs and PPIs-DOXO combination therapy on LPS-stimulated RAW 264.7 mouse macrophages were assessed.

RESULTS

Dose and time dependence cytotoxic activity of PPIs on human cancer cell lines was founded. Unlike DOXO; All PPIs had a selective cytotoxic effect in the normal fibroblasts. Unlike the equipotent OMP and ESOM; LANSO was the most potent drug with IC50 values at 72h of 99, 217, 272, 208, 181μM against A375, A549, CACO-2, MCF-7, and PANC-1, respectively. AV-PI flow cytometry revealed dose-dependent apoptotic effects of LANSO alone and substantially enhanced in DOXO-co-treatments. Interestingly unlike ESOM and OMP, LANSO proved more effective than indomethacin in LPS-stimulated RAW 264.7 macrophages. None of the tested compounds, as well as indomethacin, exerted any cytotoxicity against RAW 264.7 macrophages. PPIs-DOXO lacked potential synergistic combination antiinflammation therapies.

CONCLUSION

This study provides the evidence that PPIs induce a direct and differential cytotoxic activity against human cancer cell line by the induction of the apoptosis. Moreover, PPIs increase cancer cell lines sensitivity to doxorubicin via apoptosis augmentation. Nevertheless, PPIs-DOXO lacked potential synergistic combination therapies in either antiproliferation or anti-inflammation.

Ketogenic Diet: A New Light Shining on Old but Gold Biochemistry

Diets low in carbohydrates and proteins and enriched in fat stimulate the hepatic synthesis of ketone bodies (KB). These molecules are used as alternative fuel for energy production in target tissues. The synthesis and utilization of KB are tightly regulated both at transcriptional and hormonal levels. The nuclear receptor peroxisome proliferator activated receptor α (PPARα), currently recognized as one of the master regulators of ketogenesis, integrates nutritional signals to the activation of transcriptional networks regulating fatty acid β-oxidation and ketogenesis. New factors, such as circadian rhythms and paracrine signals, are emerging as important aspects of this metabolic regulation. However, KB are currently considered not only as energy substrates but also as signaling molecules. β-hydroxybutyrate has been identified as class I histone deacetylase inhibitor, thus establishing a connection between products of hepatic lipid metabolism and epigenetics. Ketogenic diets (KD) are currently used to treat different forms of infantile epilepsy, also caused by genetic defects such as Glut1 and Pyruvate Dehydrogenase Deficiency Syndromes. However, several researchers are now focusing on the possibility to use KD in other diseases, such as cancer, neurological and metabolic disorders. Nonetheless, clear-cut evidence of the efficacy of KD in other disorders remains to be provided in order to suggest the adoption of such diets to metabolic-related pathologies.

Anti-inflammatory effects of resolvins in diabetic nephropathy: Mechanistic pathways

The incidence of diabetes mellitus is growing rapidly. The exact pathophysiology of diabetes is unclear, but there is increasing evidence of the role of the inflammatory response in both developing diabetes as well as its complications. Resolvins are naturally occurring polyunsaturated fatty acids that are found in fish oil and sea food that have been shown to possess anti-inflammatory actions in several tissues including the kidneys. The pathways by which resolvins exert this anti-inflammatory effect are unclear. In this review we discuss the evidence showing that resolvins can suppress inflammatory responses via at least five molecular mechanisms through inhibition of the nucleotide-binding oligomerization domain protein 3 inflammasome, inhibition of nuclear factor κB molecular pathways, improvement of oxidative stress, modulation of nitric oxide synthesis/release and prevention of local and systemic leukocytosis. Complete understanding of these molecular pathways is important as this may lead to the development of new effective therapeutic strategies for diabetes and diabetic nephropathy.

A dual role of 12/15-lipoxygenase in LPS-induced acute renal inflammation and injury

Recent studies suggest a potential role of bioactive lipids in acute kidney injury induced by lipopolysaccharide (LPS). The current study was designed to determine the profiling activities of various polyunsaturated fatty acid (PUFA) metabolizing enzymes, including lipoxygenases (LO), cyclooxygenase, and cytochrome P450 in the plasma of LPS-injected mice using LC-MS. Heat map analysis revealed that out of 126 bioactive lipids screened, only the 12/15-LO metabolite, 12-HETE, had a significant (2.24 ± 0.4) fold increase relative to control (P = 0.0001) after Bonferroni Correction (BCF α = 0.003). We then determined the role of the 12/15-LO in LPS-induced acute kidney injury using genetic and pharmacological approaches. Treatment of LPS injected mice with the 12/15-LO inhibitor, baicalein, significantly reduced levels of renal injury and inflammation markers including urinary thiobarbituric acid reactive substance (TBARs), urinary monocyte chemoattractant protein-1 (MCP-1), renal interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Similarly, knocking-out of 12/15-LO reduced levels of renal inflammation and injury markers elicited by LPS injection. Next, we tested whether exogenous supplementation with docosahexaenoic acid (DHA) as a substrate would divert the role of 12/15-LO from being pro-inflammatory to anti-inflammatory via increased production of the anti-inflammatory metabolite. DHA treatment restored the decreased in plasma level of resolvin D2 (RvD2) and reduced renal injury in LPS-injected mice whereas DHA treatment failed to provide any synergistic effects in reducing renal injury in LPS injected 12/15-LO knock-out mice. The ability of RvD2 to protect kidney against LPS-induced renal injury was further confirmed by exogenous RvD2 which significantly reduced the elevation in renal injury in LPS injected mice. These data suggest a double-edged sword role of 12/15-LO in LPS-induced acute renal inflammation and injury, depending on the type of substrate available for its activity.