Eomes expression identifies the early bone marrow precursor to classical NK cells.

Natural killer (NK) cells traffic through the blood and mount cytolytic and interferon-γ (IFNγ)-focused responses to intracellular pathogens and tumors. Type 1 innate lymphoid cells (ILC1s) also produce type 1 cytokines but reside in tissues and are not cytotoxic. Whether these differences reflect discrete lineages or distinct states of a common cell type is not understood. Using single-cell RNA sequencing and flow cytometry, we focused on populations of TCF7+ cells that contained precursors for NK cells and ILC1s and identified a subset of bone marrow lineage-negative NK receptor-negative cells that expressed the transcription factor Eomes, termed EomeshiNKneg cells. Transfer of EomeshiNKneg cells into Rag2-/-Il2rg-/- recipients generated functional NK cells capable of preventing metastatic disease. By contrast, transfer of PLZF+ ILC precursors generated a mixture of ILC1s, ILC2s and ILC3s that lacked cytotoxic potential. These findings identified EomeshiNKneg cells as the bone marrow precursor to classical NK cells and demonstrated that the NK and ILC1 lineages diverged early during development.

Metabolomic profiles of cartilage and bone reflect tissue type, radiography-confirmed osteoarthritis, and spatial location within the joint.

Osteoarthritis is the most common chronic joint disease, characterized by the abnormal remodeling of joint tissues including articular cartilage and subchondral bone. However, there are currently no therapeutic drug targets to slow the progression of disease because disease pathogenesis is largely unknown. Thus, the goals of this study were to identify metabolic differences between articular cartilage and subchondral bone, compare the metabolic shifts in osteoarthritic grade III and IV tissues, and spatially map metabolic shifts across regions of osteoarthritic hip joints. Articular cartilage and subchondral bone from 9 human femoral heads were obtained after total joint arthroplasty, homogenized and metabolites were extracted for liquid chromatography-mass spectrometry analysis. Metabolomic profiling revealed that distinct metabolic endotypes exist between osteoarthritic tissues, late-stage grades, and regions of the diseased joint. The pathways that contributed the most to these differences between tissues were associated with lipid and amino acid metabolism. Differences between grades were associated with nucleotide, lipid, and sugar metabolism. Specific metabolic pathways such as glycosaminoglycan degradation and amino acid metabolism, were spatially constrained to more superior regions of the femoral head. These results suggest that radiography-confirmed grades III and IV osteoarthritis are associated with distinct global metabolic and that metabolic shifts are not uniform across the joint. The results of this study enhance our understanding of osteoarthritis pathogenesis and may lead to potential drug targets to slow, halt, or reverse tissue damage in late stages of osteoarthritis.

Blinatumomab infusion interruptions in pediatric patients rarely lead to readmission.

Blinatumomab is a bispecific T-cell engager administered as a 28-day continuous infusion. Infusions can be associated with interruptions requiring support from clinical staff, but the frequency of interventions with outpatient blinatumomab has not been characterized. This study is a single-center, retrospective review of patients who received blinatumomab between December 3, 2014 and October 31, 2021 to determine frequency and type of interventions. Forty patients received blinatumomab for 69 cycles. Clinical staff intervention was required in 31 (45%) cycles, only six (8.7%) cycles needed readmission. Management of outpatient blinatumomab infusions requires education and training of clinical staff and caregivers to quickly troubleshoot interruptions.

Metabolomic profiling to identify early urinary biomarkers and metabolic pathway alterations in autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the formation of numerous fluid-filled cysts that lead to progressive loss of functional nephrons. Currently, there is an unmet need for diagnostic and prognostic indicators of early stages of the disease. Metabolites were extracted from the urine of patients with early-stage ADPKD (n = 48 study participants) and age- and sex-matched normal controls (n = 47) and analyzed by liquid chromatography-mass spectrometry. Orthogonal partial least squares-discriminant analysis was used to generate a global metabolomic profile of early ADPKD for the identification of metabolic pathway alterations and discriminatory metabolites as candidates of diagnostic and prognostic biomarkers. The global metabolomic profile exhibited alterations in steroid hormone biosynthesis and metabolism, fatty acid metabolism, pyruvate metabolism, amino acid metabolism, and the urea cycle. A panel of 46 metabolite features was identified as candidate diagnostic biomarkers. Notable putative identities of candidate diagnostic biomarkers for early detection include creatinine, cAMP, deoxycytidine monophosphate, various androgens (testosterone; 5-α-androstane-3,17,dione; trans-dehydroandrosterone), betaine aldehyde, phosphoric acid, choline, 18-hydroxycorticosterone, and cortisol. Metabolic pathways associated with variable rates of disease progression included steroid hormone biosynthesis and metabolism, vitamin D3 metabolism, fatty acid metabolism, the pentose phosphate pathway, tricarboxylic acid cycle, amino acid metabolism, sialic acid metabolism, and chondroitin sulfate and heparin sulfate degradation. A panel of 41 metabolite features was identified as candidate prognostic biomarkers. Notable putative identities of candidate prognostic biomarkers include ethanolamine, C20:4 anandamide phosphate, progesterone, various androgens (5-α-dihydrotestosterone, androsterone, etiocholanolone, and epiandrosterone), betaine aldehyde, inflammatory lipids (eicosapentaenoic acid, linoleic acid, and stearolic acid), and choline. Our exploratory data support metabolic reprogramming in early ADPKD and demonstrate the ability of liquid chromatography-mass spectrometry-based global metabolomic profiling to detect metabolic pathway alterations as new therapeutic targets and biomarkers for early diagnosis and tracking disease progression of ADPKD.NEW & NOTEWORTHY To our knowledge, this study is the first to generate urinary global metabolomic profiles from individuals with early-stage ADPKD with preserved renal function for biomarker discovery. The exploratory dataset reveals metabolic pathway alterations that may be responsible for early cystogenesis and rapid disease progression and may be potential therapeutic targets and pathway sources for candidate biomarkers. From these results, we generated a panel of candidate diagnostic and prognostic biomarkers of early-stage ADPKD for future validation.

Metabolic phenotypes reflect patient sex and injury status: A cross-sectional analysis of human synovial fluid.

OBJECTIVE: Osteoarthritis is a heterogeneous disease. The objective was to compare differences in underlying cellular mechanisms and endogenous repair pathways between synovial fluid (SF) from male and female participants with different injuries to improve the current understanding of the pathophysiology of downstream post-traumatic osteoarthritis (PTOA). DESIGN: SF from n = 33 knee arthroscopy patients between 18 and 70 years with no prior knee injuries was obtained pre-procedure and injury pathology assigned post-procedure. SF was extracted and analyzed via liquid chromatography-mass spectrometry metabolomic profiling to examine differences in metabolism between injury pathologies (ligament, meniscal, and combined ligament and meniscal) and patient sex. Samples were pooled and underwent secondary fragmentation to identify metabolites. RESULTS: Different knee injuries uniquely altered SF metabolites and downstream pathways including amino acid, lipid, and inflammatory-associated metabolic pathways. Notably, sexual dimorphic metabolic phenotypes were examined between males and females and within injury pathology. Cervonyl carnitine and other identified metabolites differed in concentrations between sexes. CONCLUSIONS: These results suggest that different injuries and patient sex are associated with distinct metabolic phenotypes. Considering these phenotypic associations, a greater understanding of metabolic mechanisms associated with specific injuries, sex, and PTOA development may yield data regarding how endogenous repair pathways differ between male and female injury types. Ongoing metabolomic analysis of SF in injured male and female patients can be performed to monitor PTOA development and progression.

GREB1 regulates PI3K/Akt signaling to control hormone-sensitive breast cancer proliferation.

Over 70% of breast cancers express the estrogen receptor (ER) and depend on ER activity for survival and proliferation. While hormone therapies that target receptor activity are initially effective, patients invariably develop resistance which is often associated with activation of the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway. While the mechanism by which estrogen regulates proliferation is not fully understood, one gene target of ER, growth regulation by estrogen in breast cancer 1 (GREB1), is required for hormone-dependent proliferation. However, the molecular function by which GREB1 regulates proliferation is unknown. Herein, we validate that knockdown of GREB1 results in growth arrest and that exogenous GREB1 expression initiates senescence, suggesting that an optimal level of GREB1 expression is necessary for proliferation of breast cancer cells. Under both of these conditions, GREB1 is able to regulate signaling through the PI3K/Akt/mTOR pathway. GREB1 acts intrinsically through PI3K to regulate phosphatidylinositol (3,4,5)-triphosphate levels and Akt activity. Critically, growth suppression of estrogen-dependent breast cancer cells by GREB1 knockdown is rescued by expression of constitutively activated Akt. Together, these data identify a novel molecular function by which GREB1 regulates breast cancer proliferation through Akt activation and provides a mechanistic link between estrogen signaling and the PI3K pathway.

Experience using intravenous posaconazole in paediatric and young adult oncology patients.

BACKGROUND: Posaconazole exhibits broad-spectrum antifungal activity. An IV formulation became available in 2014. Few studies describing the use of this formulation exist in patients under the age of 18 years. This study describes our experience using IV posaconazole in paediatric and young adult cancer patients. METHODS: This single-centre retrospective chart review evaluated patients who received IV posaconazole and had at least one posaconazole plasma concentration obtained after five or more days with a consistent dosage. Relationships between doses required to achieve a plasma concentration of ≥1 µg/mL and patient age, weight and body surface area (BSA) were evaluated. The clinical record was reviewed to identify descriptions of any adverse events. RESULTS: Twenty-five patients were analysed, with a median age of 10.5 years (range 1.9-22.9 years; 92% were <18 years). All patients were able to achieve a posaconazole plasma concentration ≥1 µg/mL during their treatment course. The daily mg/kg/day dose required to achieve the target concentration decreased significantly with increasing age of the patient (P = 0.018). Assessment of dosage based on BSA suggested a requirement of 225 mg/m2/day across all age groups <18 years. Adverse events documented in the clinical record were consistent with those described with the oral formulations. No CNS toxicities were observed with use of IV posaconazole. CONCLUSIONS: Concentrations ≥1 µg/mL are achievable and a BSA-based dosing approach may allow a consistent empirical dose for patients <18 years of age. Therapeutic drug monitoring is recommended to ensure patients achieve therapeutic concentrations.

Activation of Cannabinoid Receptors Attenuates Endothelin-1-Induced Mitochondrial Dysfunction in Rat Ventricular Myocytes.

Evidence suggests that the activation of the endocannabinoid system offers cardioprotection. Aberrant energy production by impaired mitochondria purportedly contributes to various aspects of cardiovascular disease. We investigated whether cannabinoid (CB) receptor activation would attenuate mitochondrial dysfunction induced by endothelin-1 (ET1). Acute exposure to ET1 (4 hours) in the presence of palmitate as primary energy substrate induced mitochondrial membrane depolarization and decreased mitochondrial bioenergetics and expression of genes related to fatty acid oxidation (ie, peroxisome proliferator-activated receptor-gamma coactivator-1α, a driver of mitochondrial biogenesis, and carnitine palmitoyltransferase-1ß, facilitator of fatty acid uptake). A CB1/CB2 dual agonist with limited brain penetration, CB-13, corrected these parameters. AMP-activated protein kinase (AMPK), an important regulator of energy homeostasis, mediated the ability of CB-13 to rescue mitochondrial function. In fact, the ability of CB-13 to rescue fatty acid oxidation-related bioenergetics, as well as expression of proliferator-activated receptor-gamma coactivator-1α and carnitine palmitoyltransferase-1ß, was abolished by pharmacological inhibition of AMPK using compound C and shRNA knockdown of AMPKα1/α2, respectively. Interventions that target CB/AMPK signaling might represent a novel therapeutic approach to address the multifactorial problem of cardiovascular disease.

Higher plasma asparaginase activity after intramuscular than intravenous Erwinia asparaginase.

It is unclear if dosing intervals for Erwinase can be extended with intramuscular (i.m.) versus intravenous (i.v.) dosing. Children with acute lymphoblastic leukemia received Erwinase at 30 000-42 000 IU/m2 i.v. or i.m. I.m. Erwinase (n = 22) achieved activity above 0.1 IU/mL for longer than i.v. Erwinase (n = 33) (3.4 vs 2.9 days, P = 0.0007). With 30 000 IU/m2 Monday, Wednesday, Friday, more patients achieved adequate concentrations over the weekend with i.m. vs i.v. dosing (P = 5 × 10-36 ). A schedule with i.v. doses on Monday and Wednesday and i.m. doses on Friday of 30 000 IU/m2 maintained activity > 0.1 IU/mL over the weekend in 80% of patients.

Pentamidine for Prophylaxis against Pneumocystis jirovecii Pneumonia in Pediatric Oncology Patients Receiving Immunosuppressive Chemotherapy.

Pneumocystis jirovecii pneumonia is a life-threatening opportunistic infection in children receiving immunosuppressive chemotherapy. Without prophylaxis, up to 25% of pediatric oncology patients receiving chemotherapy will develop Pneumocystis jirovecii pneumonia. Trimethoprim-sulfamethoxazole is the preferred agent for prophylaxis against Pneumocystis jirovecii pneumonia. Pentamidine may be an acceptable alternative for pediatric patients unable to tolerate trimethoprim-sulfamethoxazole. A retrospective review was conducted of pediatric oncology patients who received ≥1 dose of pentamidine for Pneumocystis jirovecii pneumonia prophylaxis between January 2007 and August 2014. Electronic medical records were reviewed to determine the incidence of breakthrough Pneumocystis jirovecii pneumonia or discontinuation of pentamidine associated with adverse events. A total of 754 patients received pentamidine prophylaxis during the period. There were no cases of probable or proven Pneumocystis pneumonia, and 4 cases (0.5%) of possible Pneumocystis pneumonia. The incidence of possible breakthrough Pneumocystis pneumonia was not significantly different between subgroups based on age (<12 months [1.7%] versus ≥12 months [0.4%], P = 0.3), route of administration (aerosolized [0%] versus intravenous [1.0%], P = 0.2), or hematopoietic stem cell transplant status (transplant [0.4%] versus no transplant [0.8%], P = 0.6). Pentamidine was discontinued due to an adverse drug event in 23 children (3.1%), more frequently for aerosolized than for intravenous administration (7.6% versus 2.2%, respectively, P = 0.004). Intravenous or inhaled pentamidine may be a safe and effective second-line alternative for prophylaxis against Pneumocystis jirovecii pneumonia in children with cancer receiving immunosuppressive chemotherapy or hematopoietic stem cell transplantation.

Biological Activities of Stilbenoids.

Stilbenoids are a group of naturally occurring phenolic compounds found in various plant species. They share a common backbone structure known as stilbene, but differ in the nature and position of substituents. Stilbenoids are classified as phytoalexins, which are antimicrobial compounds produced de novo in plants to protect against fungal infection and toxins. In this review, the biological effects of stilbenoids such as resveratrol, pterostilbene, gnetol and piceatannol are discussed. Stilbenoids exert various biological activities ranging from cardioprotection, neuroprotection, anti-diabetic properties, depigmentation, anti-inflammation, cancer prevention and treatment. The results presented cover a myriad of models, from cell culture to animal studies as well as clinical human trials. Although positive results were obtained in most cell culture and animal studies, further human studies are needed to substantiate beneficial effects of stilbenoids. Resveratrol remains the most widely studied stilbenoid. However, there is limited information regarding the potential of less common stilbenoids. Therefore, further research is warranted to evaluate the salutary effects of various stilbenoids.

Astrocyte dysfunction in Alzheimer disease.

Astrocytes are glial cells that are distributed throughout the central nervous system in an arrangement optimal for chemical and physical interaction with neuronal synapses and brain blood supply vessels. Neurotransmission modulates astrocytic excitability by activating an array of cell surface receptors and transporter proteins, resulting in dynamic changes in intracellular Ca2+ or Na+ . Ionic and electrogenic astrocytic changes, in turn, drive vital cell nonautonomous effects supporting brain function, including regulation of synaptic activity, neuronal metabolism, and regional blood supply. Alzheimer disease (AD) is associated with aberrant oligomeric amyloid ß generation, which leads to extensive proliferation of astrocytes with a reactive phenotype and abnormal regulation of these processes. Astrocytic morphology, Ca2+ responses, extracellular K+ removal, glutamate transport, amyloid clearance, and energy metabolism are all affected in AD, resulting in a deleterious set of effects that includes glutamate excitotoxicity, impaired synaptic plasticity, reduced carbon delivery to neurons for oxidative phosphorylation, and dysregulated linkages between neuronal energy demand and regional blood supply. This review summarizes how astrocytes are affected in AD and describes how these changes are likely to influence brain function. © 2017 Wiley Periodicals, Inc.

Cannabinoid signaling in health and disease.

Cannabis sativa has long been used for medicinal purposes. To improve safety and efficacy, compounds from C. sativa were purified or synthesized and named under an umbrella group as cannabinoids. Currently, several cannabinoids may be prescribed in Canada for a variety of indications such as nausea and pain. More recently, an increasing number of reports suggest other salutary effects associated with endogenous cannabinoid signaling including cardioprotection. The therapeutic potential of cannabinoids is therefore extended; however, evidence is limited and mechanisms remain unclear. In addition, the use of cannabinoids clinically has been hindered due to pronounced psychoactive side effects. This review provides an overview on the endocannabinoid system, including known physiological roles, and conditions in which cannabinoid receptor signaling has been implicated.

Peripheral and Cerebral Resistance Arteries in the Spontaneously Hypertensive Heart Failure Rat: Effects of Stilbenoid Polyphenols.

Hypertension is associated with aberrant structure and mechanical properties of resistance arteries. We determined the effects of resveratrol, a non-flavonoid polyphenol found in foods such as red grapes, and structurally-similar analogues (pterostilbene and gnetol) on systolic blood pressure (SBP) and resistance arteries from the spontaneously hypertensive heart failure (SHHF) rat. SBP was elevated in 17-week-old SHHF vs. Sprague-Dawley rats (normotensive control; 194 ± 3 vs. 142 ± 6 mmHg, p < 0.01) and was unaffected by resveratrol, pterostilbene, or gnetol (2.5 mg/kg/d). Geometry and mechanical properties of pressurized mesenteric resistance arteries and middle cerebral arteries were calculated from media and lumen dimensions measured at incremental intraluminal pressures. SHHF arteries exhibited remodeling which consisted of augmented media-to-lumen ratios, and this was attenuated by stilbenoid treatment. Compliance was significantly reduced in SHHF middle cerebral arteries but not mesenteric arteries vis-à-vis increased wall component stiffness; stilbenoid treatment failed to normalize compliance and wall component stiffness. Our data suggest that neither AMPK nor ERK mediate stilbenoid effects. In conclusion, we observed arterial bed-specific abnormalities, where mesenteric resistance arteries exhibited remodeling and cerebral arteries exhibited remodeling and stiffening. Resveratrol, pterostilbene, and gnetol exhibited similar abilities to attenuate vascular alterations.

Disparate Effects of Stilbenoid Polyphenols on Hypertrophic Cardiomyocytes In Vitro vs. in the Spontaneously Hypertensive Heart Failure Rat.

Stilbenoids are bioactive polyphenols, and resveratrol (trans-3,5,40-trihydroxystilbene) is a representative stilbenoid that reportedly exerts cardioprotective actions. As resveratrol exhibits low oral bioavailability, we turned our attention to other stilbenoid compounds with a history of medicinal use and/or improved bioavailability. We determined the effects of gnetol (trans-3,5,20,60-tetrahydroxystilbene) and pterostilbene (trans-3,5-dimethoxy-40-hydroxystilbene) on cardiac hypertrophy. In vitro, gnetol and pterostilbene prevented endothelin-1-induced indicators of cardiomyocyte hypertrophy including cell enlargement and protein synthesis. Gnetol and pterostilbene stimulated AMP-activated protein kinase (AMPK), and inhibition of AMPK, using compound C or shRNA knockdown,abolished these anti-hypertrophiceffects. In contrast,resveratrol, gnetol, nor pterostilbene reduced blood pressure or hypertrophy in the spontaneously hypertensive heart failure (SHHF) rat. In fact, AMPK levels were similar between Sprague-Dawley and SHHF rats whether treated by stilbenoids or not. These data suggest that the anti-hypertrophic actions of resveratrol (and other stilbenoids?) do not extend to the SHHF rat, which models heart failure superimposed on hypertension. Notably, SHHF rat hearts exhibited prolonged isovolumic relaxationtime(an indicator of diastolicdys function),and this was improved by stilbenoid treatment.In conclusion, stilbenoid-based treatment as a viable strategy to prevent pathological cardiac hypertrophy,a major risk factor for heart failure,may be context-dependent and requires furtherstudy.

Astrocyte-induced cortical vasodilation is mediated by D-serine and endothelial nitric oxide synthase.

Astrocytes play a critical role in neurovascular coupling by providing a physical linkage from synapses to arterioles and releasing vaso-active gliotransmitters. We identified a gliotransmitter pathway by which astrocytes influence arteriole lumen diameter. Astrocytes synthesize and release NMDA receptor coagonist, D-serine, in response to neurotransmitter input. Mouse cortical slice astrocyte activation by metabotropic glutamate receptors or photolysis of caged Ca(2+) produced dilation of penetrating arterioles in a manner attenuated by scavenging D-serine with D-amino acid oxidase, deleting the enzyme responsible for D-serine synthesis (serine racemase) or blocking NMDA receptor glycine coagonist sites with 5,7-dichlorokynurenic acid. We also found that dilatory responses were dramatically reduced by inhibition or elimination of endothelial nitric oxide synthase and that the vasodilatory effect of endothelial nitric oxide synthase is likely mediated by suppressing levels of the vasoconstrictor arachidonic acid metabolite, 20-hydroxy arachidonic acid. Our results provide evidence that D-serine coactivation of NMDA receptors and endothelial nitric oxide synthase is involved in astrocyte-mediated neurovascular coupling.

Comparable efficacy with varying dosages of glucarpidase in pediatric oncology patients.

BACKGROUND: Glucarpidase rapidly reduces methotrexate plasma concentrations in patients experiencing methotrexate-induced renal dysfunction. Debate exists regarding the role of glucarpidase in therapy given its high cost. The use of reduced-dose glucarpidase has been reported, and may allow more institutions to supply this drug to their patients. This report explores the relationship between glucarpidase dosage and patient outcomes in pediatric oncology patients. METHODS: The authors evaluated data from 26 patients who received glucarpidase after high-dose methotrexate. Decrease in plasma methotrexate concentrations and time to renal recovery were evaluated for an association with glucarpidase dosage, which ranged from 13 to 90 units/kg. RESULTS: No significant relationship was found between glucarpidase dosage (units/kg) and percent decrease in methotrexate plasma concentrations measured by TDx (P > 0.1) or HPLC (P > 0.5). Patients who received glucarpidase dosages <50 units/kg had a median percent reduction in methotrexate plasma concentration of 99.4% (range, 98-100) measured by HPLC compared to a median percent reduction of 99.4% (range, 77.2-100) in patients who received ≥50 units/kg. Time to SCr recovery was not related to glucarpidase dosage (P > 0.8). CONCLUSIONS: The efficacy of glucarpidase in the treatment of HDMTX-induced kidney injury was not dosage-dependent in this retrospective analysis of pediatric oncology patients.

Pre-Clinical Pharmacokinetic and Pharmacodynamic Characterization of Selected Chiral Flavonoids: Pinocembrin and Pinostrobin.

PURPOSE: Delineate the stereospecific pharmacokinetics and pharmacodynamics of the chiral flavonoids pinocembrin and pinostrobin. OBJECTIVE: Characterize for the first time the stereoselective pharmacokinetics of two flavonoids, pinocembrin and pinostrobin and their bioactivity in several in vitro assays with relevant roles in heart disease, colon cancer, and diabetes etiology and pathophysiology. METHODS: Chiral flavonoids were intravenously and orally administered to male Sprague-Dawley rats. Concentrations in serum and urine were characterized via stereospecific HPLC or LC/MS. Pure enantiomeric forms of each flavonoid were tested, where possible, to identify the stereospecific contribution to bioactivity in comparison to their racemates. RESULTS: Short half-lives (0.2-6 h) in serum were observed, while a better estimation of half-life (3-26 h) and other pharmacokinetic parameters were observed using urinary data. The flavonoids are predominantly excreted via non-renal routes (fe values of 0.3-4.6 %), and undergo rapid and extensive phase II metabolism. Chiral differences in the chemical structure of these compounds result in significant pharmacodynamic differences. CONCLUSION: The importance of understanding the stereospecific pharmacokinetics and pharmacodynamics of two chiral flavonoids were delineated.This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Preclinical Pharmacokinetics and Pharmacodynamics and Content Analysis of Gnetol in Foodstuffs.

Studies were undertaken to evaluate the bioavailability in rats and content analysis of gnetol in Gnetum gnemon products reported to contain gnetol and to examine the pharmacological properties of gnetol in in vitro models including anti-inflammatory/analgesic, antidiabetic, anti-adipogenesis, and anticancer activity. Male Sprague-Dawley rats were cannulated and dosed either intravenously with gnetol (10 mg/kg) or orally (100 mg/kg). Various methanolic extractions of G. gnemon products were quantified. Gnetol's effect on cell viability in selected cell lines with or without inflammatory stimulus was assessed. α-Amylase and α-glucosidase inhibition was evaluated. Cyclooxygenase (COX)-1, COX-2, and histone deacetylase inhibition and adipogenesis inhibition were examined. After oral and intravenous administration, gnetol was detected in both serum and urine as the parent compound and as a glucuronidated metabolite. The bioavailability of gnetol was determined to be 6%. Gnetol is rapidly glucuronidated and is excreted in urine and via nonrenal routes. Gnetol was found to exist as an aglycone and as a glycoside in G. gnemon products. Gnetol showed concentration-dependent reductions in cell viability in cancer cell lines with greatest activity in colorectal cancer and potent COX-1, histone deacetylase, and weak COX-2 activities along with limited reduction in inflammation. Gnetol also possessed concentration-dependent alpha-amylase, alpha-glucosidase, and adipogenesis activities. Pretreatment of mice with gnetol was able to increase the latency period to response in analgesia models.