Antihyperglycemic and aphrodisiac effect of West African Albizia (Albizia zygia) leaves-inclusive diet in diabetes-induced erectile dysfunctional rats.

ETHNOPHARMACOLOGICAL RELEVANCE: West African Albizia (Albizia zygia DC J. F. Macbr) leaves are a tropical plant that are frequently used in folkloric medicine to treat a number of illnesses, including type 2 diabetes (TY2D) and erectile dysfunction (ED), without having a complete scientific foundation. AIM OF THE STUDY: This investigation examined the effect of action of dietary augmentation of Albizia zygia leaves (AZL) on rat sexual functioning and important enzymes related to TY2D and ED. MATERIALS AND METHODS: Thirty matured adult Wistar rats of the weight 180-200 g were acclimatized in a lab environmental condition for two weeks prior to experiment given food and water to acclimate. Twenty-four of the rats got high fat diet (HFD) for periods of two weeks before receiving streptozotocin (STZ) intraperitoneally (i.p.), 35 mg/kg body weight single dose. Six rats got basal diets. Type 2 diabetes was identified in rats 72 h after STZ treatment. Rats were then used to evaluate the mounting number, mount delay, intromission number, and intromission latency. RESULTS: Following that, meals supplemented with AZL (5% or 10% inclusion) were given to diabetic-ED rats for 14 days. AZL was added. Therefore, in diabetic-ED rats, AZL supplementation could significantly (p0.05) lower blood glucose levels and the activities of alpha amylase, alpha glucosidase, phosphodiesterase-5, and arginase. In the case of diabetic-ED treated rats in consideration with diabetic-ED control group, nitric oxide levels were increased along with sexual function. CONCLUSION: Thus, experimental results of this study demonstrated rats that consumed AZL in their diets had less erectile dysfunction. In order to address ED caused by diabetes, AZL could be suggested as functional meals.

Triptolide inhibits the proinflammatory potential of myeloid-derived suppressor cells via reducing Arginase-1 in rheumatoid arthritis.

Triptolide (TPT) is widely used in the treatment of rheumatoid arthritis (RA). However, its regulatory mechanisms are not fully understood. This study demonstrated that Myeloid-derived suppressor cells (MDSCs) were expanded in both RA patients and arthritic mice. The frequency of MDSCs was correlated with RA disease severity and T helper 17 (Th17) responses. MDSCs from RA patients promoted the polarization of Th17 cells in vitro, which could be substantially attenuated by blocking arginase-1 (Arg-1). TPT inhibited the differentiation of MDSCs, particularly the monocytic MDSCs (M-MDSCs) subsets, as well as the expression of Arg-1 in a dose dependent manner. Alongside, TPT treatment reduced the potential of MDSCs to promote the polarization of IL-17+ T cell in vitro. Consistently, TPT immunotherapy alleviated adjuvant-induced arthritis (AIA) in a mice model, and reduced the frequency of MDSCs, M-MDSCs and IL-17+ T cells simultaneously. The presented data suggest a pathogenic role of MDSCs in RA and may function as a novel and effective therapeutic target for TPT in RA.

Ginseng-derived nanoparticles reprogram macrophages to regulate arginase-1 release for ameliorating T cell exhaustion in tumor microenvironment.

BACKGROUND: Lines of evidence indicated that, immune checkpoints (ICs) inhibitors enhanced T cell immune response to exert anti-tumor effects. However, T cell exhaustion has been so far a major obstacle to antitumor immunotherapy in colorectal cancer patients. Our previous studies showed that ginseng-derived nanoparticles (GDNPs) inhibited the growth of various tumors by reprograming tumor-associated macrophages (TAMs) and downregulated the ICs expression on T cells in tumor microenvironment (TME), but the underlying effector mechanisms remained unclear. METHODS: The correlation between arginase-1 (ARG1) and T cells was computed based on the colorectal cancer patients in TCGA database. In vitro, we observed that GDNPs reprogrammed TAMs inhibited ARG1 release and ultimately ameliorated T cell exhaustion according to several techniques including WB, PCR, ELISA and flow cytometry. We also used an in vivo MC38 tumor-bearing model and administered GDNPs to assess their anti-tumor effects through multiple indices. The mechanism that GDNPs improved T cell exhaustion was further clarified using the bioinformatics tools and flow cytometry. RESULTS: GDNPs reprogramed TAMs via reducing ARG1 production. Moreover, normalized arginine metabolism ameliorated T cell exhaustion through mTOR-T-bet axis, resulting in reduced ICs expression and enhanced CD8+ T cells expansion. CONCLUSIONS: By regulating the mTOR-T-bet axis, GDNPs reprogramed macrophages to regulate ARG1 release, which further ameliorated T cell exhaustion in TME. These findings provided new insights into comprehending the mechanisms underlying the mitigation of T cell exhaustion, which may facilitate the development of innovative therapeutic strategies in the field of cancer treatment.

Systemic Effects of Homoarginine Supplementation on Arginine Metabolizing Enzymes in Rats with Heart Failure with Preserved Ejection Fraction.

A restoration of low homoarginine (hArg) levels in obese ZSF1 rats (O-ZSF1) before (S1-ZSF1) and after (S2-ZSF1) the manifestation of heart failure with preserved ejection fraction (HFpEF) did not affect the worsening of cardiac HFpEF characteristics. Here, potential regulation of key enzymes of arginine metabolism in other organs was analyzed. Arginase 2 (ARG2) was reduced >35% in the kidney and small intestine of hArg-supplemented rats compared to O-ZSF1. Glycine amidinotransferase (GATM) was 29% upregulated in the kidneys of S1-ZSF1. Dimethylarginine dimethylaminohydrolase 1 (DDAH1) levels were reduced >50% in the livers of O-ZSF1 but restored in S2-ZSF1 compared to healthy rats (L-ZSF1). In the skeletal muscle, iNOS was lower in O-ZSF1 and further decreased in S1-ZSF1 and S2-ZSF1 compared to L-ZSF1. iNOS levels were lower in the liver of the S2-ZSF1 group but higher in the kidneys of S1-ZSF1 compared to L-ZSF1. Supplementation with hArg in an in vivo HFpEF model resulted in the inhibition of renal ARG2 and an increase in GATM expression. This supplementation might contribute to the stabilization of intestinal iNOS and ARG2 imbalances, thereby enhancing barrier function. Additionally, it may offer protective effects in skeletal muscle by downregulating iNOS. In the conceptualization of hArg supplementation studies, the current disease progression stage as well as organ-specific enzyme regulation should be considered.

Phosphodiesterase 5 and Arginase Inhibitory Activities of the Extracts from Some Members of Nelumbonaceae and Nymphaeaceae Families.

The objectives of this study were (1) to investigate the effect of extracts from some plants in the families Nelumbonaceae and Nymphaeaceae on phosphodiesterase 5 (PDE5) and arginase, which have been used in erectile dysfunction treatment, and (2) to isolate and identify the compounds responsible for such activities. The characterization and quantitative analysis of flavonoid constituents in the active extracts were performed by HPLC. Thirty-seven ethanolic extracts from different parts of plants in the genus Nymphaea and Victoria of Nymphaeaceae and genus Nelumbo of Nelumbonaceae were screened for PDE5 and arginase inhibitory activities. The ethanolic extracts of the receptacles and pollens of Nelumbo nucifera Gaertn., petals of Nymphaea cyanea Roxb. ex G.Don, Nymphaea stellata Willd., and Victoria amazonica (Poepp.) Sowerby and the petals and receptacles of Nymphaea pubescens Willd. showed IC50 values on PDE5 of less than 25 µg/mL while none of the extracts showed effects on arginase. The most active extract, N. pubescens petal extract, was fractionated to isolate and identify the PDE5 inhibitors. The results showed that six flavonoid constituents including quercetin 3'-O-ß-xylopyranoside (1), quercetin 3-methyl ether 3'-O-ß-xylopyranoside (2), quercetin (3), 3-O-methylquercetin (4), kaempferol (5) and 3-O-methylkaempferol (6) inhibited PDE5 with IC50 values at the micromolar level.

Arginase inhibitory activities of guaiane sesquiterpenoids from Curcuma comosa rhizomes.

Arginases are bimanganese enzymes involved in many human illnesses, and thus are targets for disease treatments. The screening of traditional medicinal plants demonstrated that an ethanol extract of Curcuma comosa rhizomes showed significant human arginase I and II inhibitory activity, and further fractionation led to the isolation of three known guaiane sesquiterpenoids, alismoxide (1), 7α,10α-epoxyguaiane-4α,11-diol (2) and guaidiol (3). Tests of their inhibitory activities on human arginases I and II revealed that 1 exhibited selective and potent competitive inhibition for human arginase I (IC50 = 30.2 µM), whereas the other compounds lacked inhibitory activities against human arginases. To the best of our knowledge, this is the first demonstration of human arginase I inhibitory activity by a sesquiterpenoid. Thus, 1 is a primary and specific inhibitory molecule against human arginase I.

Tetramerization of STAT5 regulates monocyte differentiation and the dextran sulfate sodium-induced colitis in mice.

In response to external stimuli during immune responses, monocytes can have multifaceted roles such as pathogen clearance and tissue repair. However, aberrant control of monocyte activation can result in chronic inflammation and subsequent tissue damage. Granulocyte-macrophage colony-stimulating factor (GM-CSF) induces monocyte differentiation into a heterogenous population of monocyte-derived dendritic cells (moDCs) and macrophages. However, the downstream molecular signals that dictate the differentiation of monocytes under pathological conditions is incompletely understood. We report here that the GM-CSF-induced STAT5 tetramerization is a critical determinate of monocyte fate and function. Monocytes require STAT5 tetramers to differentiate into moDCs. Conversely, the absence of STAT5 tetramers results in a switch to a functionally distinct monocyte-derived macrophage population. In the dextran sulfate sodium (DSS) model of colitis, STAT5 tetramer-deficient monocytes exacerbate disease severity. Mechanistically, GM-CSF signaling in STAT5 tetramer-deficient monocytes results in the overexpression of arginase I and a reduction in nitric oxide synthesis following stimulation with lipopolysaccharide. Correspondingly, the inhibition of arginase I activity and sustained supplementation of nitric oxide ameliorates the worsened colitis in STAT5 tetramer-deficient mice. This study suggests that STAT5 tetramers protect against severe intestinal inflammation through the regulation of arginine metabolism.

Surface TREM2 on circulating M-MDSCs as a novel prognostic factor for adults with treatment-naïve diffuse large B-cell lymphoma.

INTRODUCTION: Circulating monocytic myeloid-derived suppressive cells (M-MDSCs) are implicated as a poor prognostic factor and cause CAR T-cell failure in diffuse large B-cell lymphoma (DLBCL). Triggering receptors expressed on myeloid cells 2 (TREM2) are a transmembrane glycoprotein that polarize macrophages to anti-inflammation phenotype but have never been explored on M-MDSCs. This study aims to elucidate the expression and clinical impact of surface TREM2 on circulating M-MDSCs derived from DLBCL adults. METHODS: This prospective, observational study enrolled 100 adults with newly diagnosed and treatment-naïve DLBCL from May 2019 to October 2021. Human circulating M-MDSCs were obtained from freshly isolated peripheral blood, and each patient's surface-TREM2 level on M-MDSCs was normalized via a healthy control at the same performance of flow-cytometry analysis. Murine MDSCs derived from bone marrow (BM-MDSCs) were adopted to assess the link between Trem2 and cytotoxic T lymphocytes. RESULTS: More circulating M-MDSCs at diagnosis of DLBCL predicted worse progression-free (PFS) and overall survival (OS). Patients with higher IPI scores, bone marrow involvement, or lower absolute counts of CD4+ or CD8+ T cells in PB had significantly higher normalized TREM2 levels on M-MDSCs. Additionally, normalized TREM2 levels on M-MDSCs could be grouped into low (< 2%), medium (2-44%), or high (> 44%) levels, and a high normalized TREM2 level on M-MDSCs was proven as an independent prognostic factor for both PFS and OS via multivariate Cox regression analysis and associated with worst PFS and OS. Interestingly, normalized levels of surface TREM2 on M-MDSCs were negatively associated with absolute counts of PB CD8+ T cells and positively correlated with levels of intracellular arginase 1 (ARG1) within M-MDSCs. Wild-type BM-MDSCs had significantly higher mRNA levels of Arg1 and showed more prominent ability to suppress the proliferation of co-cultured CD8+ T cells than BM-MDSCs from Trem2 knockout mice, and the suppressive ability could be impaired by adding Arg1 inhibitors (CB1158) or supplementing L-arginine. CONCLUSION: In treatment-naïve DLBCL adults, a high surface-TREM2 level on circulating M-MDSCs is a poor prognostic factor for both PFS and OS and warrants further investigation for its potential as a novel target in immunotherapy.

Gastrodin programs an Arg-1+ microglial phenotype in hippocampus to ameliorate depression- and anxiety-like behaviors via the Nrf2 pathway in mice.

BACKGROUND: Regulating the microglial phenotype is an attractive strategy for treating diseases of the central nervous system such as depression and anxiety. Gastrodin can quickly cross the blood-brain barrier and mitigate microglia-mediated inflammation, which widely used to treat a variety of central nervous system diseases associated with microglial dysfunction. However, the molecular mechanism by which gastrodin regulates the functional phenotype of microglia remains unclear. PURPOSE: Since the transcription factor "nuclear factor erythroid 2-related factor 2″ (Nrf2) is associated with the anti-inflammatory effects of gastrodin, we hypothesized that gastrodin induces Nrf2 expression in microglia and thereby programs an anti-inflammatory phenotype. STUDY DESIGN: Male C57BL/6 mice, treated or not with gastrodin, were given lipopolysaccharide (LPS) at 0.25 mg/kg/d for 10 days to induce chronic neuroinflammation. The effects of gastrodin on microglial phenotypes, neuroinflammation and depression- and anxiety-like behaviors were evaluated. In another experiment, animals were treated with Nrf2 inhibitor ML385 throughout the 13-day gastrodin intervention period. METHODS: The effects of gastrodin on depression- and anxiety-like behaviors were evaluated through the sucrose preference test, forced swimming test, open field test and elevated plus-maze test; as well as its effects on morphology and molecular and functional phenotypes of hippocampal microglia through immunohistochemistry, real-time PCR and enzyme-linked immunosorbent assays. RESULTS: Chronic exposure to LPS caused hippocampal microglia to secrete inflammatory cytokines, their somata to enlarge, and their dendrites to lose branches. These changes were associated with depression- and anxiety-like behaviors. Gastrodin blocked these LPS-induced alterations and promoted an Arg-1+ microglial phenotype that protected neurons from injury. The effects of gastrodin were associated with Nrf2 activation, whereas blockade of Nrf2 antagonized gastrodin. CONCLUSION: These results suggest that gastrodin acts via Nrf2 to promote an Arg-1+ microglial phenotype, which buffers the harmful effects of LPS-induced neuroinflammation. Gastrodin may be a promising drug against central nervous system diseases that involve microglial dysfunction.

Delicaflavone reactivates anti-tumor immune responses by abrogating monocytic myeloid cell-mediated immunosuppression.

BACKGROUND: Myeloid cell-mediated immunosuppression is a major obstacle to checkpoint blockade immunotherapy. We previously reported that total biflavonoids extract from Selaginella doederleinii (TBESD) and a flavone monomer isolated from TBESD, named Delicaflavone, have favorable anti-tumor activity. However, whether TBESD and Delicaflavone could affect the tumor microenvironment (TME) remains unclear. PURPOSE: In this study, we focused on the TME to determine whether TBESD and Delicaflavone could restore anti-tumor immune response. METHODS: 4T1 tumor-bearing immunocompetent BALB/c mice and T cell-deficient nude mice were used to examine the effect of TBESD on T cell-mediated immunity in vivo. Multi-parameter flow cytometry was conducted to evaluate the impacts of TBESD on TME. Primary cells, including murine CD8+ T cells, tumor associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) were prepared to investigate the modulatory activities of TBESD on immune cells. It was further determined whether Delicaflavone or Amentoflavone, two typical functional biflavones from TBESD, mediated those effects of TBESD. Finally, the impacts of TBESD and Delicaflavone on Jak1/STAT6 signaling pathway were explored via western blot. RESULTS: We found that TBESD significantly reduced 4T1 tumor growth in immunocompetent BALB/c mice, but not in nude mice. This effect was associated with the regulation of TME, shown as an increase in functional T cells and M1 phenotype TAMs (M1-TAMs), and a decrease in M2 phenotype TAMs (M2-TAMs), monocytic-MDSCs (M-MDSCs) and regulatory T cells (Tregs) in TBESD-treated BALB/c mouse 4T1 tumors. It was found ex vivo that TBESD restrained the viability and immunosuppressive properties of M2-TAMs and M-MDSCs, especially for the loss of arginase-1 expression. Additionally, TBESD re-educated M2-TAMs to an M1 like phenotype. Further investigations determined that Delicaflavone predominantly mediated the immuno-modulatory activities of TBESD both ex vivo and in vivo. Finally, Delicaflavone and TBESD blocked Jak1/STAT6 signaling pathway in M2-TAMs and MDSCs. CONCLUSION: The present study suggests Delicaflavone as a potent natural inhibitor of M2-TAMs and MDSCs, which fills the gap in knowledge on the immuno-modulatory effects of TBESD and Delicaflavone, and could have translational implications to improve the efficacy of cancer immunotherapy.

Calcaratarin D, a labdane diterpenoid, attenuates mouse asthma via modulating alveolar macrophage function.

BACKGROUND AND PURPOSE: Alveolar macrophages (AMs) contribute to airway inflammation and remodelling in allergic asthma. Calcaratarin D (CalD), a labdane diterpenoid from rhizomes of the medicinal plant Alpinia calcarata, has recently been shown to possess anti-inflammatory properties. The present study evaluated protective effects of CalD in a house dust mite (HDM)-induced asthma mouse model. EXPERIMENTAL APPROACH: The effects of CalD on AMs in contributing to anti-inflammatory effects in asthma were investigated through in vivo, ex vivo, and in vitro experiments. KEY RESULTS: CalD reduced total bronchoalveolar lavage fluid and differential cell count, serum IgE levels, mucus hypersecretion, and airway hyperresponsiveness in HDM-challenged mice. Additionally, CalD affected a wide array of pro-inflammatory cytokines and chemokines and oxidative damage markers in isolated lung tissues. CalD suppressed the HDM-induced increase in Arg1 (M2 macrophage marker) in AMs from lung tissue and reduced lung polyamine levels. CalD weakened antigen presentation capability of AMs by reducing CD80 expression, reduced AM-derived CCL17 and CCL22 levels, and lessened Th2 cytokines from CD4+ T-cells from asthma lung digest. CalD blocked the HDM-induced FoxO1/IRF4 pathway and restored impaired the Nrf2/HO-1 antioxidant pathway in lung tissues. CalD inhibited IL-4/IL-13-stimulated JAK1/STAT6 pathway, FoxO1 protein expression, and chemokine production in primary AMs. Structure-activity relationship study revealed the α,ß-unsaturated γ-butyrolactone in CalD is capable of forming covalent bonds with cellular protein targets essential for its action. CONCLUSION AND IMPLICATIONS: Our results demonstrate for the first time that CalD is a novel anti-inflammatory natural compound for allergic asthma that modulates AM function.

Capparis spinosa inhibits Leishmania major growth through nitric oxide production in vitro and arginase inhibition in silico.

Cutaneous leishmaniasis is an infectious disease, considered as a major public health problem in different regions of the world. The current treatments are limited due to their toxicity and treatment failures, which have increased the search for new substances of natural origin to control this infection. Capparis spinosa is an important medicinal plant, rich in biochemical compounds with a broad range of activities including antimicrobial effects. Nevertheless, more investigations are still needed to determine its effect on Leishmania parasites. This study aimed to evaluate the effect of C. spinosa' extracts on Leishmania major promastigotes and amastigotes growth as well as on L-arginine metabolic pathways, especially the production of leishmanicidal molecules such as nitric oxide. Our results showed that C. spinosa' methanolic and aqueous extracts contained polyphenols and flavonoids at different concentrations. The methanolic extract of C. spinosa, compared to the aqueous extract, showed significantly higher amounts of total polyphenols (21.23 ± 1.08) mg GAE/g of dw (P < 0.05), as well as a higher antioxidant activity evaluated respectively by Reducing Power and DPPH (EC50: 0.31 ± 0.02 and 7.69 ± 1.28) mg/ml. Both extracts significantly inhibited L. major promastigotes and intra-macrophagic amastigotes growth in vitro in a dose-dependent manner (P < 0.001) and induced NO production not only in Leishmania-infected macrophages but also in uninfected macrophages, without showing any cytotoxicity in vitro. Furthermore, in silico docking studies showed that C. spinosa compounds identified by RP-HPLC exhibited inhibitory activity against the arginase enzyme. The leishmanicidal effect of C. spinosa may be due to its phenolic content and its mechanism of action may be mediated by an increase in NO production and by the inhibition of arginase enzyme in silico. These findings support the hypothesis that C. spinosa might be a valuable source of new biomolecules for leishmaniasis treatment.

Loss of selenoprotein W in murine macrophages alters the hierarchy of selenoprotein expression, redox tone, and mitochondrial functions during inflammation.

Macrophages play a pivotal role in mediating inflammation and subsequent resolution of inflammation. The availability of selenium as a micronutrient and the subsequent biosynthesis of selenoproteins, containing the 21st amino acid selenocysteine (Sec), are important for the physiological functions of macrophages. Selenoproteins regulate the redox tone in macrophages during inflammation, the early onset of which involves oxidative burst of reactive oxygen and nitrogen species. SELENOW is a highly expressed selenoprotein in bone marrow-derived macrophages (BMDMs). Beyond its described general role as a thiol and peroxide reductase and as an interacting partner for 14-3-3 proteins, its cellular functions, particularly in macrophages, remain largely unknown. In this study, we utilized Selenow knock-out (KO) murine bone marrow-derived macrophages (BMDMs) to address the role of SELENOW in inflammation following stimulation with bacterial endotoxin lipopolysaccharide (LPS). RNAseq-based temporal analyses of expression of selenoproteins and the Sec incorporation machinery genes suggested no major differences in the selenium utilization pathway in the Selenow KO BMDMs compared to their wild-type counterparts. However, selective enrichment of oxidative stress-related selenoproteins and increased ROS in Selenow-/- BMDMs indicated anomalies in redox homeostasis associated with hierarchical expression of selenoproteins. Selenow-/- BMDMs also exhibited reduced expression of arginase-1, a key enzyme associated with anti-inflammatory (M2) phenotype necessary to resolve inflammation, along with a significant decrease in efferocytosis of neutrophils that triggers pathways of resolution. Parallel targeted metabolomics analysis also confirmed an impairment in arginine metabolism in Selenow-/- BMDMs. Furthermore, Selenow-/- BMDMs lacked the ability to enhance characteristic glycolytic metabolism during inflammation. Instead, these macrophages atypically relied on oxidative phosphorylation for energy production when glucose was used as an energy source. These findings suggest that SELENOW expression in macrophages may have important implications on cellular redox processes and bioenergetics during inflammation and its resolution.

Inhibiting Human and Leishmania Arginases Using Cannabis sativa as a Potential Therapy for Cutaneous Leishmaniasis: A Molecular Docking Study.

Cutaneous leishmaniasis (CL), a vector-borne parasitic disease caused by the Leishmania protozoan, is a serious public health problem in Morocco. The treatment of this disease is still based on pentavalent antimonials as the primary therapy, but these have associated side effects. Thus, the development of effective, risk-free alternative therapeutics based on natural compounds against leishmaniasis is urgent. Arginase, the key enzyme in the polyamine biosynthetic pathway, plays a critical role in leishmaniasis outcome and has emerged as a potential therapeutic target. The objective of this study was to test Cannabis sativa's phytochemical components (cannabinoids and terpenoids) through molecular docking against Leishmania and human arginase enzymes. Our results showed that delta-9-tetrahydrocannabinol (THC) possessed the best binding energies of -6.02 and -6.35 kcal/mol with active sites of Leishmania and human arginases, respectively. Delta-9-THC interacted with Leishmania arginase through various amino acids including His139 and His 154 and linked to human arginase via His 126. In addition to delta-9-THC, caryophyllene oxide and cannabidiol (CBD) also showed a good inhibition of Leishmania and human arginases, respectively. Overall, the studied components were found to inhibit both arginases active sites via hydrogen bonds and hydrophobic interactions. These components may serve as therapeutic agents or in co-administrated therapy for leishmaniasis.

Genetic regulation of iron homeostasis in sideropenic patients with mild COVID-19 disease under a new oral iron formulation: Lessons from a different perspective.

BACKGROUND: Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) needs iron to replicate itself. Coronaviruses are able to upregulate Chop/Gadd153 and Arg1 genes, consequently leading to CD8 lymphocytes decrease, degradation of asparagine and decreased nitric oxide (NO), thus impairing immune response and antithrombotic functions. Little is known about regulation of genes involved in iron metabolism in paucisymptomatic patients with COVID-19 disease or in patients with iron deficiency treated with sucrosomial iron. METHODS: Whole blood was taken from the COVID-19 patients and from patients with sideropenic anemia, treated or not (control group) with iron supplementations. Enrolled patients were: affected by COVID19 under sucrosomal iron support (group A), affected by COVID-19 not under oral iron support (group B), iron deficiency not under treatment, not affected by COVID19 (control group). After RNA extraction and complementary DNA (cDNA) synthesis of Arg1, Hepcidin and Chop/Gadd153, gene expression from the 3 groups was measured by qRT-PCR. M2 macrophages were detected by cytofluorimetry using CD163 and CD14 markers. RESULTS: Forty patients with COVID-19 (group A), 20 patients with iron deficiency treated with sucrosomial iron (group B) and 20 patients with iron deficiency not under treatment (control group) were enrolled. In all the patients supported with oral sucrosomial iron, the gene expression of Chop, Arg1 and Hepcidin genes was lower than in sideropenic patients not supported with iron, M1 macrophages polarization and functional iron deficiency was also lower in group A and B, than observed in the control group. CONCLUSIONS: New oral iron formulations, as sucrosomial iron, are able to influence the expression of genes like Chop and Arg1 and to influence M2 macrophage polarization mainly in the early phase of COVID-19 disease.

Arginase-1 targeting peptide vaccine in patients with metastatic solid tumors - A phase I trial.

Background: Arginase-1-producing cells inhibit T cell-mediated anti-tumor responses by reducing L-arginine levels in the tumor microenvironment. T cell-facilitated elimination of arginase-1-expressing cells could potentially restore L-arginine levels and improve anti-tumor responses. The activation of arginase-1-specific T cells may convert the immunosuppressive tumor microenvironment and induce or strengthen local Th1 inflammation. In the current clinical study, we examined the safety and immunogenicity of arginase-1-based peptide vaccination. Methods: In this clinical phase I trial, ten patients with treatment-refractory progressive solid tumors were treated. The patients received an arginase-1 peptide vaccine comprising three 20-mer peptides from the ARG1 immunological "hot spot" region in combination with the adjuvant Montanide ISA-51. The vaccines were administered subcutaneously every third week (maximum 16 vaccines). The primary endpoint was to evaluate safety assessed by Common Terminology Criteria for Adverse Events 4.0 and laboratory monitoring. Vaccine-specific immune responses were evaluated using enzyme-linked immune absorbent spot assays and intracellular cytokine staining on peripheral blood mononuclear cells. Clinical responses were evaluated using Response Evaluation Criteria in Solid Tumors 1.1. Results: The vaccination was feasible, and no vaccine-related grade 3-4 adverse events were registered. Nine (90%) of ten patients exhibited peptide-specific immune responses in peripheral blood mononuclear cells. Six (86%) of the seven evaluable patients developed a reactive T cell response against at least one of the ARG1 peptides during treatment. A phenotypic classification revealed that arginase-1 vaccine-specific T cells were both CD4+ T cells and CD8+ T cells. Two (20%) of ten patients obtained stable disease for respectively four- and seven months on vaccination treatment. Conclusion: The peptide vaccine against arginase-1 was safe. Nine (90%) of ten patients had measurable peptide-specific responses in the periphery blood, and two (20%) of ten patients attained stable disease on protocol treatment. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT03689192, identifier NCT03689192.

Almond and date fruits enhance antioxidant status and have erectogenic effect: Evidence from in vitro and in vivo studies.

This study was designed to investigate the efficacies of almond and date fruits on redox imbalance and enzymes relevant to the pathogenesis of erectile dysfunction. The total polyphenol contents, ferric reducing antioxidant power, and vitamin C content were determined spectrophotometrically. Phenolic and amino acid compositions were quantified using HPLC; meanwhile, the antioxidant activities were determined using DPPH, ABTS, FRAP, and metal chelation. Also, the effect of almond and date extract on advanced glycated end-products (AGEs) formation, arginase, and phosphodiesterase-5 activities was evaluated in vitro. Thereafter, the influence of almond and date supplemented diets on copulatory behaviors in normal rats was assessed, followed by arginase and phosphodiesterase-5 activities determination in vivo. The results revealed that date and almond extracts exerted antioxidant properties, prevented AGEs formation in vitro, and inhibited arginase and phosphodiesterase-5 activities in vitro and in vivo. Besides, almond and date supplemented diets significantly enhance sexual behaviors in normal rats when compared with the control. Among the active compounds identified were gallic acid, ellagic acid, quercetin, and rutin. All the 20 basic amino acids were identified. Given the aforementioned, date and almond could represent a reliable source of functional foods highly rich in compounds with antioxidant activity, and arginase and PDE-5 inhibitory properties. PRACTICAL APPLICATIONS: Fruits are essential part of the human diet that furnish the body with important nutrients. Despite the crucial roles of fruits in human diets, some fruits like almond and date are underutilized among Nigerians. However, we characterized the important compounds present in these fruits and how their presence contributes to the biological activities of the fruits. Finally, we relate the chemical composition and the observed biological activities to the overall health and wellness of the consumers.

Antihyperglycemic activity of L-norvaline and L-arginine in high-fat diet and streptozotocin-treated male rats.

BACKGROUND: A decrease in nitric oxide (NO) bioavailability has been shown to cause hyperglycemia, type II diabetes mellitus (DM), and chronic cardio-metabolic complications. In turn, hyperglycemia and hypercholesterolemia are associated with increased oxidative stress that leads to reduced nitric oxide bioavailability through disruption of L-arginine transport into cells, inactivation of nitric oxide synthase, and activation of arginase. Upregulation of arginase has been demonstrated in both diabetic patients and animal models of hyperglycemia and type 2 diabetes. L-norvaline is a nonselective inhibitor of arginase that increases NO production and promotes the normal functioning of the vascular endothelium. Another means of increasing NO bioavailability in the cardiovascular system is L-arginine supplementation. Whether L-norvaline and L-arginine have antihyperglycemic effects has not been studied. HYPOTHESIS: We hypothesized that inhibition of arginase will provide an antihyperglycemic effect and, as a result of the recovery of NO bioavailability, will protect against oxidative stress and hypercholesterolemia. METHODS: Rats were fed a high-fat diet (HFD) for three weeks concomitant with the two-time injection of 30 mg/kg of streptozotocin (STZ) to induce stable hyperglycemia. We studied the antihyperglycemic properties of arginase inhibition (via L-norvaline) and its combination with NOS substrate supplementation (via L-arginine). RESULTS: Treatment of HFD/STZ mice with L-norvaline and L-arginine reduced fasting blood glucose levels by 27.1% vs. untreated HFD/STZ rats (p < 0.001). Blood levels of total cholesterol, low-density lipoprotein (LDL), and malondialdehyde (MDA), a marker for oxidative stress, were significantly decreased in both L-norvaline- and L-norvaline+L-arginine-treated HFD/STZ rats when compared with untreated rats. In addition, administration of L-norvaline and L-arginine reversed the progression of pancreatic and kidney pathology in HFD/STZ rats as assessed by histology (p < 0.001). CONCLUSIONS: Both L-norvaline and L-arginine act as potent antihyperglycemic agents and can represent alternative therapeutic tools in individuals with hyperglycemia and pre-diabetes.

Effects of increasing supplemental zinc in beef feedlot steers administered a steroidal implant and beta agonist.

Ninety-two Angus-crossbred steers (424 ±â€…28.3 kg initial body weight) were used in a 98-d study to assess the effects of increasing Zn supplementation on cattle performance, liver and plasma trace mineral concentrations, blood metabolites, and carcass characteristics. All steers were implanted with a Component TE-200 (200 mg trenbolone acetate + 20 mg estradiol; Elanco Animal Health, Greenfield, IN) on d 0 and fed 300 mg‧steer-1‧d-1 of ractopamine hydrochloride (Zoetis, Parsippany, NJ) from d 70 to 98. Cattle were fed via GrowSafe bunks (GrowSafe Systems Ltd., Airdrie, AB, Canada), and steer served as the experimental unit (n = 22 or 23 steers/treatment). Supplemental Zn was administered through the diet at 0, 100, 150, or 180 mg Zn/kg on a dry matter basis from ZnSO4 (Zn0, Zn100, Zn150, or Zn180, respectively). Cattle were weighed on d -1, 0, 9/10, 20, 41, 59, 69, 70, 78/79, 97, and 98. Blood was collected on d 0, 9/10, 69, 78/79, and 97, and liver biopsies on d 9/10 and 78/79 (n = 12 steers/treatment). Data were analyzed as a complete randomized design. Contrast statements were formed to test the linear, quadratic, and cubic effects of Zn supplementation and test Zn0 vs. Zn supplementation. Day 10 and 70 body weight (BW) and d 0 to 10 and 0 to 70 average daily gain were linearly increased with Zn supplementation (P ≤ 0.05), and greater for Zn supplemented steers (P ≤ 0.03). No effects of Zn supplementation were observed on final BW, dressing percentage, ribeye area, 12th rib fat, or marbling (P ≥ 0.11). Hot carcass weight tended to be 7 kg greater for Zn supplemented steers than Zn0 (P = 0.07), and yield grade linearly increased with increasing Zn supplementation (P = 0.02). Day 10 liver Mn concentrations tended to quadratically decrease (P = 0.08) with increasing Zn supplementation, though d 79 liver Mn concentrations and arginase activity were not influenced by Zn (P ≥ 0.28). Day 10 liver arginase activity tended to be (r = 0.27; P = 0.07) and d 10 serum urea nitrogen was correlated with d 10 liver Mn (r = 0.55; P < 0.0001). Zinc supplementation linearly increased d 10 liver Zn and d 10, 69, 79, and 97 plasma Zn concentrations (P ≤ 0.05). A cubic effect of Zn was observed on d 79 liver Zn (P = 0.01) with lesser liver Zn in Zn0 and Zn150 steers. These data suggest increasing dietary Zn improves growth directly following the administration of a steroidal implant and that steroidal implants and beta agonists differ in their effects on protein metabolism.

Lysine and homoarginine are closely interrelated metabolites in the rat.

L-Lysine (Lys) and L-arginine (Arg), but not L-homoarginine (hArg), are proteinogenic amino acids. In healthy humans, oral administration of hArg increased the plasma concentration of Lys, suggesting Lys as a metabolite of hArg. In humans and animals, hArg is biosynthesized from Arg and Lys by arginine:glycine amidinotransferase (AGAT). In vitro, recombinant human arginase and bovine liver arginase I hydrolyzed hArg to Lys, suggesting Lys as a metabolite of hArg. The aim of the present study was to investigate whether changes in blood concentrations of hArg and Lys in old rats fed for 4 months with varied controlled experimental diets could suggest interconversion of these amino acids. Blood samples (n = 253) were taken before (T0) and after 2 months (T2) and 4 months (T4) of the experiment. Plasma concentrations of Lys and hArg were determined by gas chromatography-mass spectrometry. The plasma hArg concentration markedly correlated with the plasma Lys concentration at all timepoints (r ≥ 0.7, P < 0.0001). Further analysis demonstrated that hArg and Lys are closely and specifically associated independently of experimental time/rat age and diet, suggesting that hArg and Lys are mutual metabolites in old rats. Based on the plasma concentration changes, the median yield of hArg from Lys was determined to be 0.17% at T0 and each 0.27% at T2 and T4. With a circulating concentration of about 3 µM, hArg a major metabolite of Lys in healthy humans. hArg supplementation is currently investigated as a cardioprotective means to improve impaired hArg synthesis. Present knowledge suggests that Lys rather than hArg supplementation may be even more favorable.