A new R,R-RvD6 isomer with protective actions following corneal nerve injury.

The transparent cornea is the most densely innervated tissue in the body, primarily by sensory nerves originating from the trigeminal ganglia (TG). Damage to corneal nerves reduces sensitivity and tear secretion and results in dry eye. Consequently, ocular pain, for which no satisfactory therapies exist, arises in many cases. Treatment of injured corneas with pigment epithelium-derived factor (PEDF) combined with docosahexaenoic acid (DHA) stimulates nerve regeneration in models of refractive surgery, which damages nerves. The mechanism involves the synthesis of a stereoisomer of resolvin D6 (R,R-RvD6) formed after incorporating DHA into membrane lipids. Activation of a PEDF receptor (PEDF-R) with phospholipase activity releases DHA to synthesize the new resolvin isomer, which is secreted via tears. Topical treatment of mice corneas with R,R-RvD6 shows higher bioactivity in regenerating nerves and increasing sensitivity compared to PEDF+DHA. It also stimulates a transcriptome in the TG that modulates genes involved in ocular pain. Our studies suggest an important therapeutic role for R,R-RvD6 in regenerating corneal nerves and decreasing pain resulting from dry eye.

Anti-inflammatory actions of aspirin-triggered resolvin D1 (AT-RvD1) in bronchial epithelial cells stimulated by cigarette smoke extract.

Smoking causes several diseases such as chronic obstructive pulmonary disease (COPD). Aspirin-triggered-resolvin D1 (AT-RvD1) is a lipid mediator produced during the resolution of inflammation and demonstrates anti-inflammatory and pro-resolution effects in several inflammatory experimental models including in the airways. Here we evaluated the role of AT-RvD1 (100 nM) in bronchial epithelial cells (BEAS-2B) stimulated by cigarette smoke extract (CSE; 1%; 1 cigarette) for 24 h. CSE induced the productions of IL-1ß, TNF-α, IL-10, IL-4 and IFN-γ as well as the activations of NF-κB and STAT3 and the expression of ALX/FPR2 receptor. AT-RvD1 reduced the IL-1ß and TNF-α production and increased the production of IFN-γ. These effects were reversed BOC2, an antagonist of ALX/FPR2 receptor for AT-RvD1. The production of IL-4 and IL-10 were not altered by AT-RvD1. In addition, AT-RvD1 reduced the phosphorylation of NF-κB and STAT3 when compared to CSE-stimulated BEAS-2B cells. No alteration of ALX/FPR2 expression was observed by AT-RvD1 when compared to CSE group. In the human monocytic leukemia cell line, the relative number of copies of IL-1ß and IL-4 was significantly higher in CSE + AT-RvD1 group compared CSE group, however, the expression of M1 cytokine was more pronounced than M2 profile. AT-RvD1 could be an important target for the reduction of inflammation in the airways associated with smoking.

Fatty Acid-Binding Protein 4-Mediated Regulation Is Pivotally Involved in Retinal Pathophysiology: A Review.

Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.

Resolvin D1 attenuates mechanical allodynia after burn injury: Involvement of spinal glia, p38 mitogen-activated protein kinase, and brain-derived neurotrophic factor/tropomyosin-related kinase B signaling.

Resolvin D1 (RvD1) suppresses inflammatory, postoperative, and neuropathic pain. The present study assessed the roles and mechanisms of RvD1 in mechanical allodynia after burn injury. A rat model of burn injury was established for analyses, and RvD1 was injected intraperitoneally. Pain behavior and the expression levels of spinal dorsal horn Iba-1 (microglia marker), GFAP (astrocyte marker), p-p38 mitogen-activated protein kinase (MAPK), brain-derived neurotrophic factor (BDNF), and tropomyosin-related kinase B (TrkB) were detected by behavioral and immunocytochemical assays. The results showed that RvD1 attenuated mechanical allodynia after burn injury, prevented microglial and astroglial activation, and downregulated p-p38 MAPK in microglia and BDNF/TrkB following burn injury. Similarly, inhibition of p38 MAPK and BDNF/TrkB signaling attenuated mechanical allodynia after burn injury. In addition, inhibition of p38 MAPK prevented spinal microglial activation and downregulated BDNF/TrkB following burn injury. Furthermore, inhibition of BDNF/TrkB signaling prevented spinal microglial activation and downregulated p-p38 MAPK within spinal microglia. Taken together, this study demonstrated that RvD1 might attenuate mechanical allodynia after burn injury by inhibiting spinal cord glial activation, microglial p38 MAPK, and BDNF/TrkB signaling in the spinal dorsal horn.

Rituximab-bortezomib-dexamethasone induce high response rates in iMCD in clinical practice.

Treatment options for idiopathic multicentric Castleman disease (iMCD) are currently limited, especially for patients who do not respond or are resistant to interleukin-6 inhibitors. For the first time, we innovatively designed a protocol using rituximab-bortezomib-dexamethasone (RVD) as first-line consolidation therapy in patients newly diagnosed with iMCD. Furthermore, we adopted a no-maintenance treatment strategy to simplify post-remission care. Five patients with iMCD were enrolled (including one with TAFRO syndrome) and underwent the RVD regimen, all of whom achieved partial response (PR) or better. After four cycles of RVD, three (60%) patients achieved PR, while one (20%) achieved a complete response. These five patients, who achieved PR or better, discontinued treatment but remained stable for a median follow-up of 11 months, with a duration of response of 7, 7, 10, 12 and 13 months, respectively. None of the patients experienced grade ≥3 adverse events during the observation period. Collectively, these findings demonstrated that the RVD regimen may be a promising treatment option for patients with iMCD. It was a safe and effective approach that resulted in lasting responses without the need for ongoing maintenance therapy.

Prolonged experimental sleep disturbance affects the inflammatory resolution pathways in healthy humans.

BACKGROUND: Sleep disturbances, as manifested in insomnia symptoms of difficulties falling asleep or frequent nighttime awakenings, are a strong risk factor for a diverse range of diseases involving immunopathology. Low-grade systemic inflammation has been frequently found associated with sleep disturbances and may mechanistically contribute to increased disease risk. Effects of sleep disturbances on inflammation have been observed to be long lasting and remain after recovery sleep has been obtained, suggesting that sleep disturbances may not only affect inflammatory mediators, but also the so-called specialized pro-resolving mediators (SPMs) that actively resolve inflammation. The goal of this investigation was to test for the first time whether the omega-3 fatty acid-derived D- (RvD) and E-series (RvE) resolvins are impacted by prolonged experimental sleep disturbance (ESD). METHODS: Twenty-four healthy participants (12 F, age 20-42 years) underwent two 19-day in-hospital protocols (ESD/control), separated by > 2 months. The ESD protocol consisted of repeated nights of short and disrupted sleep with intermittent nights of undisturbed sleep, followed by three nights of recovery sleep at the end of the protocol. Under the control sleep condition, participants had an undisturbed sleep opportunity of 8 h/night throughout the protocol. The D- and E-series resolvins were measured in plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: The precursor of the D-series resolvins, 17-HDHA, was downregulated in the ESD compared to the control sleep condition (p <.001 for condition), and this effect remained after the third night of recovery sleep has been obtained. This effect was also observed for the resolvins RvD3, RvD4, and RvD5 (p <.001 for condition), while RvD1 was higher in the ESD compared to the control sleep condition (p <.01 for condition) and RvD2 showed a mixed effect of a decrease during disturbed sleep followed by an increase during recovery sleep in the ESD condition (p <.001 for condition*day interaction). The precursor of E-series resolvins, 18-HEPE, was downregulated in the ESD compared to the control sleep condition (p <.01 for condition) and remained low after recovery sleep has been obtained. This effect of downregulation was also observed for RvE2 (p <.01 for condition), while there was no effect for RvE1 (p >.05 for condition or condition*day interaction). Sex-differential effects were found for two of the D-series resolvins, i.e., RvD2 and RvD4. CONCLUSION: This first investigation on the effects of experimental sleep disturbance on inflammatory resolution processes shows that SPMs, particularly resolvins of the D-series, are profoundly downregulated by sleep disturbances and remain downregulated after recovery sleep has been obtained, suggesting a longer lasting impact of sleep disturbances on these mediators. These findings also suggest that sleep disturbances contribute to the development and progression of a wide range of diseases characterized by immunopathology by interfering with processes that actively resolve inflammation. Pharmacological interventions aimed at promoting inflammatory resolution physiology may help to prevent future disease risk as a common consequence of sleep disturbances. TRIAL REGISTRATION: ClinicalTrials.gov NCT02484742.

DHA, RvD1, RvD5, and MaR1 reduce human coronary arteries contractions induced by PGE2.

In patients with coronary artery disease (CAD), plasma levels of pro-inflammatory lipid mediators such as PGE2 and TxA2 are increased. They could increase vascular contraction while EPA and DHA could reduce it. Studies have been mostly conducted on animal vessels. Therefore, the aim of the study was to investigate if EPA, DHA, and DHA-derived metabolites: RvD1, RvD5 and MaR1 can modulate contraction of human coronary arteries (HCA) induced by PGE2 or TxA2 stable analogue (U46619). DHA and EPA relaxed HCA pre-contracted with PGE2. 18 h-incubation with DHA but not EPA reduced the PGE2-induced contractions. Pre-incubation with RvD1, RvD5 and MaR1 reduced the PGE2-induced contractions. Indomethacin did not significantly modify the PGE2 responses. L-NOARG (inhibitor of nitric oxide synthase), reduced only the PGE2-induced contractions in RvD1-treated rings. Finally, FPR2/ALX, GPR32 and LGR6 receptors are detected in HCA by immunofluorescence. Our results indicate that DHA and its metabolites could be beneficial for HCA blood flow and could be a therapeutic perspective for patients with CAD.

15-Epi-LXA4 and 17-epi-RvD1 restore TLR9-mediated impaired neutrophil phagocytosis and accelerate resolution of lung inflammation.

Timely resolution of bacterial infections critically depends on phagocytosis of invading pathogens by polymorphonuclear neutrophil granulocytes (PMNs), followed by PMN apoptosis and efferocytosis. Here we report that bacterial DNA (CpG DNA) and mitochondrial DNA impair phagocytosis and attenuate phagocytosis-induced apoptosis in human PMNs through Toll-like receptor 9 (TLR9)-mediated release of neutrophil elastase and proteinase 3 and subsequent down-regulation of the complement receptor C5aR. Consistently, CpG DNA delays pulmonary clearance of Escherichia coli in mice and suppresses PMN apoptosis, efferocytosis, and generation of proresolving lipid mediators, thereby prolonging lung inflammation evoked by E. coli Genetic deletion of TLR9 renders mice unresponsive to CpG DNA. We also show that aspirin-triggered 15-epi-lipoxin A4 (15-epi-LXA4) and 17-epi-resolvin D1 (17-epi-RvD1) through the receptor ALX/FPR2 antagonize cues from CpG DNA, preserve C5aR expression, restore impaired phagocytosis, and redirect human PMNs to apoptosis. Treatment of mice with 15-epi-LXA4 or 17-epi-RvD1 at the peak of inflammation accelerates clearance of bacteria, blunts PMN accumulation, and promotes PMN apoptosis and efferocytosis, thereby facilitating resolution of E. coli-evoked lung injury. Collectively, these results uncover a TLR9-mediated endogenous mechanism that impairs PMN phagocytosis and prolongs inflammation, and demonstrate both endogenous and therapeutic potential for 15-epi-LXA4 and 17-epi-RvD1 to restore impaired bacterial clearance and facilitate resolution of acute lung inflammation.

Renal Deletion of LRRC8/VRAC Channels Induces Proximal Tubulopathy.

BACKGROUND: Volume-regulated anion channels (VRACs) are heterohexamers of LRRC8A with LRRC8B, -C, -D, or -E in various combinations. Depending on the subunit composition, these swelling-activated channels conduct chloride, amino acids, organic osmolytes, and drugs. Despite VRACs' role in cell volume regulation, and large osmolarity changes in the kidney, neither the localization nor the function of VRACs in the kidney is known. METHODS: Mice expressing epitope-tagged LRRC8 subunits were used to determine the renal localization of all VRAC subunits. Mice carrying constitutive deletions of Lrrc8b-e, or with inducible or cell-specific ablation of Lrrc8a, were analyzed to assess renal functions of VRACs. Analysis included histology, urine and serum parameters in different diuresis states, and metabolomics. RESULTS: The kidney expresses all five VRAC subunits with strikingly distinct localization. Whereas LRRC8C is exclusively found in vascular endothelium, all other subunits are found in the nephron. LRRC8E is specific for intercalated cells, whereas LRRC8A, LRRC8B, and LRRC8D are prominent in basolateral membranes of proximal tubules. Conditional deletion of LRRC8A in proximal but not distal tubules and constitutive deletion of LRRC8D cause proximal tubular injury, increased diuresis, and mild Fanconi-like symptoms. CONCLUSIONS: VRAC/LRRC8 channels are crucial for the function and integrity of proximal tubules, but not for more distal nephron segments despite their larger need for volume regulation. LRRC8A/D channels may be required for the basolateral exit of many organic compounds, including cellular metabolites, in proximal tubules. Proximal tubular injury likely results from combined accumulation of several transported molecules in the absence of VRAC channels.

Aspirin-Triggered Resolvin D1 (AT-RvD1) Protects Mouse Skin against UVB-Induced Inflammation and Oxidative Stress.

Intense exposure to UVB radiation incites excessive production of reactive oxygen species (ROS) and inflammation. The resolution of inflammation is an active process orchestrated by a family of lipid molecules that includes AT-RvD1, a specialized proresolving lipid mediator (SPM). AT-RvD1 is derived from omega-3, which presents anti-inflammatory activity and reduces oxidative stress markers. The present work aims to investigate the protective effect of AT-RvD1 on UVB-induced inflammation and oxidative stress in hairless mice. Animals were first treated with 30, 100, and 300 pg/animal AT-RvD1 (i.v.) and then exposed to UVB (4.14 J/cm2). The results showed that 300 pg/animal of AT-RvD1 could restrict skin edema, neutrophil and mast cell infiltration, COX-2 mRNA expression, cytokine release, and MMP-9 activity and restore skin antioxidant capacity as per FRAP and ABTS assays and control O2•- production, lipoperoxidation, epidermal thickening, and sunburn cells development. AT-RvD1 could reverse the UVB-induced downregulation of Nrf2 and its downstream targets GSH, catalase, and NOQ-1. Our results suggest that by upregulating the Nrf2 pathway, AT-RvD1 promotes the expression of ARE genes, restoring the skin's natural antioxidant defense against UVB exposition to avoid oxidative stress, inflammation, and tissue damage.

Stereoselective Synthesis, Configurational Assignment and Biological Evaluations of the Lipid Mediator RvD2n-3 DPA.

Herein we report the first total synthesis of RvD2n-3 DPA , an endogenously formed mediator biosynthesized from the omega-3 fatty acid n-3 docosapentaenoic acid. The key steps are the Midland Alpine borane reduction, Sonogashira cross-coupling reactions, and a Z-selective alkyne reduction protocol, yielding RvD2n-3 DPA methyl ester in 13 % yield over 12 steps (longest linear sequence). The physical property data (UV chromophore, chromatography and MS/MS fragmentation) of the synthetic lipid mediator matched those obtained from biologically produced material. Moreover, synthetic RvD2n-3 DPA also carried the potent biological activities of enhancing macrophage uptake of Staphylococcus aureus and zymosan A bioparticles.

Resolvin D1 protects against Aspergillus fumigatus keratitis in diabetes by blocking the MAPK-NF-κB pathway.

Fungal keratitis (FK) is one of the main causes of blindness in China. People with diabetes are susceptible to corneal epithelial disease, even fungal keratitis. At present, there are few studies on this disease. Resolvins (Rv) has been reported as a mediators that exert crucial anti-inflammatory and immune regulation roles in serval diseases. In order to investigate the roles and underlying mechanism of Resolvins D1 (RvD1) on the Aspergillus fumigatus (A. fumigatus) keratitis in diabetes, we established in vivo and in vitro models of A. fumigatus keratitis, which were then exposed to high glucose. The expression levels of RvD1, 5-lipoxygenase (5-LOX), and 15-lipoxygenase (15-LOX) in A. fumigatus keratitis patients with diabetes were determined through Enzyme Linked Immunosorbent Assay (ELISA), Western blot and immunohistochemistry. Reactive Oxygen Species (ROS) production, ELISA, flow cytometry, Hematoxylin-Eosin (HE) staining and fungal loading determination were conducted to evaluate the severity of A. fumigatus infection. Lymphangiogenesis and angiogenesis were examined by immunofluorescence assay. Western blot was applied to detect the proteins of the MAPK-NF-κB pathway. The results showed that RvD1 diminished the high glucose-induced oxidative stress and inflammatory response, as evidenced by the reduction of ROS production, Interleukin-6 (IL-6), Interleukin-8 (IL-8), Heme Oxygenase-1 (HMOX-1), and the elevation of Cyclooxygenase-2 (COX2), Superoxide Dismutase (SOD-1), and Glutathione Peroxidase-2 (GPX2) levels in A. fumigatus-infected Human Corneal Endothelial Cells (HCECs). Additionally, lymphangiogenesis and angiogenesis prominently decreased after intervention with RvD1. Furthermore, RvD1 significantly reduced the levels of p-MEK1/2 and p-ERK1/2, and restrained the NF-κB and GPR32 activation. The above results showed that RvD1 protects against A. fumigatus keratitis in diabetes by suppressing oxidative stress, inflammatory response, fungal growth, and immunoreaction via modulating MAPK-NF-κB pathway. RvD1 provides clues for the therapeutic targets of Fungal keratitis complicated with diabetes.

The inhibiting effect of Aspirin Triggered-Resolvin D1 in non-canonical pyroptosis in rats with acute keratitis.

PURPOSE: To investigate the effect of Aspirin Triggered-Resolvin D1 (AT-RvD1) as an anti-pyroptosis and anti-inflammatory agent on lipopolysaccharide (LPS) induced acute keratitis in Wistar rats. METHODS: Acute keratitis in rats were induced by LPS stromal injection. Inflammatory reaction was measured by clinical score and histological observations. The non-canonical pyroptosis, the role of AT-RvD1 and Docosahexaenoic Acid (DHA) on non-canonical pyroptosis, were verified by quantification real-time PCR (qRT-PCR) and Western-blot. Besides, Human corneal epithelial cells (HCECs) primed with LPS, were stimulated with Nigericin, AT-RvD1 and necrosulfonamide (NSA), a Gasdermin-D (GSDMD) inhibitor separately. CCK-8 tests and flow cytometry were conducted to evaluate the cell viability and death ratio. And the marker of non-canonical pyroptosis were verified by Western blot. RESULTS: AT-RvD1 and DHA both alleviated the inflammation of rat cornea through inhibiting the expression of Caspase-11 and p30 which was triggered by LPS. Meanwhile, the activation of Caspase-4 and p30 were also significantly suppressed by AT-RvD1 in vitro, which is consistent with the results in rats. CONCLUSIONS: The non-canonical pyroptosis signaling pathways played an important role in rats with acute keratitis. In addition, AT-RvD1 can exert as an anti-inflammatory activity by inhibiting the non-canonical pyroptosis. Hence, it may be a promising and safe agent in treating acute keratitis.

Elucidating the structure and functions of Resolvin D6 isomers on nerve regeneration with a distinctive trigeminal transcriptome.

Innervation sustains cornea integrity. Pigment epithelium-derived factor (PEDF) plus docosahexaenoic acid (DHA) regenerated damaged nerves by stimulating the synthesis of a new stereoisomer of Resolvin D6 (RvD6si). Here, we resolved the structure of this lipid isolated from mouse tears after injured corneas were treated with PEDF + DHA. RvD6si synthesis was inhibited by fluvoxamine, a cytochrome P450 inhibitor, but not by 15- or 5-LOX inhibitors, suggesting that the 4- and 17-hydroxy of DHA have an RR- or SR-configuration. The two compounds were chemically synthesized. Using chiral phase HPLC, four peaks of RvD6si1-4 from tears were resolved. The RR-RvD6 standard eluted as a single peak with RvD61 while pure SR-RvD6 eluted with RvD63 . The addition of these pure mediators prompted a trigeminal ganglion transcriptome response in injured corneas and showed that RR-RvD6 was the more potent, increasing cornea sensitivity and nerve regeneration. RR-RvD6 stimulates Rictor and hepatocyte growth factor (hgf) genes specifically as upstream regulators and a gene network involved in axon growth and suppression of neuropathic pain, indicating a novel function of this lipid mediator to maintain cornea integrity and homeostasis after injury.

Resolvin D1 suppresses inflammation-associated tumorigenesis in the colon by inhibiting IL-6-induced mitotic spindle abnormality.

While failure in resolution of inflammation is considered to increase the risk of tumorigenesis, there is paucity of experimental as well as clinical evidence supporting this association. Resolvin D1 (RvD1) is a representative pro-resolving lipid mediator that is endogenously generated from docosahexaenoic acid for the resolution of inflammation. Here, we report a decreased level of RvD1 in the blood from colorectal cancer patients and mice having inflammation-induced colon cancer, suggesting plasma RvD1 as a potential biomarker for monitoring colorectal cancer. Administration of RvD1 attenuated dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM) plus DSS-induced colorectal carcinogenesis by suppressing the production of interleukin-6 (IL-6) and IL-6-mediated chromosomal instability. The protective effect of RvD1 against chromosomal instability is associated with downregulation of IL-6-induced Cyclin D1 expression, which appears to be mediated by blocking the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) axis. RvD1 inhibited the STAT3 signaling pathway by interfering with the binding of IL-6 to its receptor (IL-6R), suggesting the novel function of RvD1 as a putative IL-6R antagonist. Together, our findings suggest that RvD1-mediated blockade of IL-6 signal transmission may contribute to inhibition of chromosomal instability and tumorigenesis.

A plain language summary of daratumumab plus lenalidomide/bortezomib/dexamethasone in transplant-eligible Black patients with newly diagnosed multiple myeloma in the GRIFFIN study.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a publication about Black participants of the GRIFFIN clinical study that was published in Blood Cancer Journal in April 2022. The GRIFFIN clinical study looked at the treatment combination of daratumumab plus a standard therapy for multiple myeloma (called RVd therapy, which stands for lenalidomide, bortezomib, and dexamethasone) in adult patients who had not been treated before for multiple myeloma and so were considered to have newly diagnosed multiply myeloma. Multiple myeloma is a blood cancer of plasma cells. Based on the participants' age, medical history, and indicators of good general health, the participants in the GRIFFIN study were also eligible to receive autologous stem cell transplant as part of their therapy. This summary describes results for the Black participants of the GRIFFIN clinical study who received daratumumab plus RVd therapy (called D-RVd) to see if D-RVd therapy is better than RVd therapy at reducing the amount of multiple myeloma cancer cells in a patient's body. WHY DID THE RESEARCHERS EVALUATE THE RESULTS FOR BLACK PATIENTS IN THE GRIFFIN STUDY?: Due to racial disparities leading to historically low representation of minority groups in clinical studies, optimal treatments are not defined for Black patients with newly diagnosed multiple myeloma. Since previously published results from the overall population in the GRIFFIN study indicated that D-RVd therapy was better than RVd therapy, the researchers wanted to determine if this was also the case among Black participants. WHAT WERE THE RESULTS?: Out of 207 participants in the GRIFFIN study, 15% (32 participants) were Black and 78% (161 participants) were White. In both Black and White participants, D-RVd therapy reduced the amount of myeloma cancer cells more than RVd therapy. Additionally, D-RVd and RVd therapy had similar safety results for Black and White participants. WHAT DO THE RESULTS MEAN?: This analysis of GRIFFIN by race shows that Black people benefit from the daratumumab-containing D-RVd therapy as much as White people. Additionally, D-RVd therapy had similar safety results to RVd therapy for both Black and White people. Clinical Trial Registration: NCT02874742 (ClinicalTrials.gov).

Enhanced silver nanoparticle-induced pulmonary inflammation in a metabolic syndrome mouse model and resolvin D1 treatment.

BACKGROUND: Metabolic syndrome (MetS) exacerbates susceptibility to inhalation exposures such as particulate air pollution, however, the mechanisms responsible remain unelucidated. Previously, we determined a MetS mouse model exhibited exacerbated pulmonary inflammation 24 h following AgNP exposure compared to a healthy mouse model. This enhanced response corresponded with reduction of distinct resolution mediators. We hypothesized silver nanoparticle (AgNP) exposure in MetS results in sustained pulmonary inflammation. Further, we hypothesized treatment with resolvin D1 (RvD1) will reduce exacerbations in AgNP-induced inflammation due to MetS. RESULTS: To evaluate these hypotheses, healthy and MetS mouse models were exposed to vehicle (control) or AgNPs and a day later, treated with resolvin D1 (RvD1) or vehicle (control) via oropharyngeal aspiration. Pulmonary lung toxicity was evaluated at 3-, 7-, 14-, and 21-days following AgNP exposure. MetS mice exposed to AgNPs and receiving vehicle treatment, demonstrated exacerbated pulmonary inflammatory responses compared to healthy mice. In the AgNP exposed mice receiving RvD1, pulmonary inflammatory response in MetS was reduced to levels comparable to healthy mice exposed to AgNPs. This included decreases in neutrophil influx and inflammatory cytokines, as well as elevated anti-inflammatory cytokines. CONCLUSIONS: Inefficient resolution may contribute to enhancements in MetS susceptibility to AgNP exposure causing an increased pulmonary inflammatory response. Treatments utilizing specific resolution mediators may be beneficial to individuals suffering MetS following inhalation exposures.

Effect of resolvin D1 on experimental bacterial keratitis to prevent corneal scar.

PURPOSE: The study aims to investigate the role of the lipid mediator resolvin D1 (RvD1) in bacterial keratitis in a murine model. METHODS: The effect of RvD1 on Pseudomonas aeruginosa-stimulated human corneal epithelial cells (HCECs) and mouse macrophages and dendritic cells (DCs) was assessed. C57BL/6 mouse corneas were abraded and treated with RvD1 after stimulation with P. aeruginosa, following which cytokine production level in the cornea and drainage lymph nodes was compared with that in controls. Corneal opacity and thickness were assessed using anterior segment photographs, and optical coherence tomography and corneal infiltrates were analyzed using immunohistochemistry for neutrophils. RESULTS: RvD1 significantly inhibited pro-inflammatory cytokine production in HCECs, mouse macrophages, and DCs. Corneal opacity and corneal thickness were reduced, and the development of corneal infiltrates, specifically neutrophils, was also significantly inhibited by RvD1 in response to stimulation with P. aeruginosa. CONCLUSIONS: RvD1 inhibits P. aeruginosa-induced corneal inflammation. This finding supports a potential therapeutic approach for patients with bacterial keratitis.

Sex-mediated elevation of the specialized pro-resolving lipid mediator levels in a Sjögren's syndrome mouse model.

Our previous results showed that the specialized pro-resolving mediator (SPM) Resolvin D1 (RvD1) promotes resolution of inflammation in salivary glands in non-obese diabetic (NOD)/ShiLtJ, a mouse model for Sjögren's syndrome (SS). Additionally, mice lacking the RvD1 receptor ALX/FPR2 show defective innate and adaptive immune responses in salivary glands. Particularly, ALX/FPR2 KO mice exhibit exacerbated inflammation in their salivary glands in response to systemic LPS treatment. Moreover, female ALX/FPR2 KO mice show increased autoantibody production and loss of salivary gland function with age. Together, these studies suggest that an underlying SPM dysregulation could be contributing to SS progression. Therefore, we investigated whether SPM production is altered in NOD/ShiLtJ using metabololipidomics and enzyme-linked immunosorbent assay (ELISA). Our results demonstrate that SPM levels were broadly elevated in plasma collected from NOD/ShiLtJ female mice after disease onset, whereas these drastic changes did not occur in male mice. Moreover, gene expression of enzymes involved in SPM biosynthesis were altered in submandibular glands (SMG) from NOD/ShiLtJ female mice after disease onset, with 5-LOX and 12/15-LOX being downregulated and upregulated, respectively. Despite this dysregulation, the abundances of the SPM products of these enzymes (ie, RvD1 and RvD2) were unaltered in freshly isolated SMG cells suggesting that other cell populations (eg, lymphocytes) may be responsible for the overabundance of SPMs that we observed. The elevation of SPMs noted here appeared to be sex mediated, meaning that it was observed only in one sex (females). Given that SS primarily affects females (roughly 90% of diagnosed cases), these results may provide some insights into the mechanisms underlying the observed sexual dimorphism.

Quantitative profiling of inflammatory and pro-resolving lipid mediators in human adolescents and mouse plasma using UHPLC-MS/MS.

OBJECTIVES: Lipid mediators are bioactive lipids which help regulate inflammation. We aimed to develop an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method to quantify 58 pro-inflammatory and pro-resolving lipid mediators in plasma, determine preliminary reference ranges for adolescents, and investigate how total parenteral nutrition (TPN) containing omega-3 polyunsaturated fatty acid (n-3 PUFA) or n-6 PUFA based lipid emulsions influence lipid mediator concentrations in plasma. METHODS: Lipid mediators were extracted from plasma using SPE and measured using UHPLC-MS/MS. EDTA plasma was collected from healthy adolescents between 13 and 17 years of age to determine preliminary reference ranges and from mice given intravenous TPN for seven days containing either an n-3 PUFA or n-6 PUFA based lipid emulsion. RESULTS: We successfully quantified 43 lipid mediators in human plasma with good precision and recovery including several leukotrienes, prostaglandins, resolvins, protectins, maresins, and lipoxins. We found that the addition of methanol to human plasma after blood separation reduces post blood draw increases in 12-hydroxyeicosatetraenoic acid (12-HETE), 12-hydroxyeicosapentaenoic acid (12-HEPE), 12S-hydroxyeicosatrienoic acid (12S-HETrE), 14-hydroxydocosahexaenoic acid (14-HDHA) and thromboxane B2 (TXB2). Compared to the n-6 PUFA based TPN, the n-3 PUFA based TPN increased specialized pro-resolving mediators such as maresin 1 (MaR1), MaR2, protectin D1 (PD1), PDX, and resolvin D5 (RvD5), and decreased inflammatory lipid mediators such as leukotriene B4 (LTB4) and prostaglandin D2 (PGD2). CONCLUSIONS: Our method provides an accurate and sensitive quantification of 58 lipid mediators from plasma samples, which we used to establish a preliminary reference range for lipid mediators in plasma samples of adolescents; and to show that n-3 PUFA, compared to n-6 PUFA rich TPN, leads to a less inflammatory lipid mediator profile in mice.