Inferring a causal relationship between ceramide levels and COVID-19 respiratory distress

A causal relationship between plasma ceramide concentration and respiratory distress symptoms in COVID-19 patients is inferred. In this study, plasma samples of 52 individuals infected with COVID-19 were utilized in a lipidomic analysis. Lipids belonging to the ceramide class exhibited a 400-fold increase in total plasma concentration in infected patients. Further analysis led to the demonstration of concentration dependency for severe COVID-19 respiratory symptoms in a subclass of ceramides. The subclasses Cer(d18:0/24:1), Cer(d18:1/24:1), and Cer(d18:1/22:0) were shown to be increased by 48-, 40-, and 33-fold, respectively, in infected plasma samples and to 116-, 91- and 50-fold, respectively, in plasma samples with respiratory distress. Hence, monitoring plasma ceramide concentration, can be a valuable tool for measuring effects of therapies on COVID-19 respiratory distress patients.

Cerebrospinal fluid exposure to bictegravir/emtricitabine/tenofovir in HIV-1-infected patients with CNS impairment

Objectives The penetration of antiretroviral drugs into deep compartments, such as the CNS, is a crucial component of strategies towards an HIV cure. This study aimed to determine CSF concentrations of bictegravir, emtricitabine and tenofovir in patients with HIV-related CNS impairment (HCI) enrolled in a real-life observational study. Methods Patients with HCI treated by optimized ART, including bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) for at least 1 month were enrolled. Plasma and CSF concentrations were measured by quality control-validated assays (LC-MS/MS). The inhibitory quotient (IQARV) was calculated as the ratio of unbound (bictegravir) or total (emtricitabine and tenofovir) concentration to half (or 90%) maximal inhibitory concentration for bictegravir (or emtricitabine and tenofovir). All numerical variables are expressed as median (range). Results Twenty-four patients (nine women) were enrolled. The age was 45 (26–68) years. Unbound bictegravir and total emtricitabine and tenofovir CSF concentrations were 4.4 (1.6–9.6), 84.4 (28.6–337.4) and 1.6 (0.7–4.3) ng/mL, respectively. The unbound bictegravir CSF fraction was 34% (15%–82%) versus 0.33% (0.11%–0.92%) in plasma. Three patients had an IQARV above unity for the three antiretrovirals. Factors positively associated with the CSF concentration (unbound for bictegravir) were age and total plasma concentration for the three antiretrovirals. Patients aged over 51 years had higher CSF concentrations (unbound for bictegravir). Conclusions We observed low CSF exposure to bictegravir, emtricitabine and tenofovir. These results suggest that BIC/FTC/TAF should be used with caution as first-line treatment for people living with HIV with HCI under 51 years of age.

Ceramide Levels and COVID-19 Respiratory Distress, a Causal Relationship

A causal relationship between plasma ceramide concentration and respiratory distress symptoms in COVID-19 patients is presented. In this study, plasma samples of 52 individuals infected with COVID-19 were utilized in a lipidomic analysis. Lipids belonging to the ceramide class exhibited a 400-fold increase in total plasma concentration in infected patients. Further analysis led to the demonstration of concentration dependency for severe COVID-19 respiratory symptoms in a subclass of ceramides. The subclasses Cer(d18:0/24:1), Cer(d18:1/24:1), and Cer(d18:1/22:0) were shown to be increased by 48-, 40-, and 33-fold, respectively, in infected plasma samples and to 116-, 91- and 50-fold, respectively, in plasma samples with respiratory distress. Hence, monitoring plasma ceramide concentration, targeting ceramide synthesis, its salvage and its regulatory mechanisms are validated approaches towards enhancing survival from COVID-19 respiratory distress.

Ceramide Levels and Covid-19 Respiratory Distress, a Causal Relationship

A causal relationship between plasma ceramide concentration and Covid-19 patients with respiratory distress symptoms is presented. In this study, plasma samples of 52 individuals infected with Covid-19 were utilized in a lipidomic analysis. Lipids belonging to ceramide class exhibited a 400-fold increase in total plasma concentration in infected patients. Further analysis lead to demonstration of concentration dependency, for severe Covid-19 respiratory symptoms, in a subclass of ceramides. The subclasses Cer(d18:0/24:1), Cer(d18:1/24:1), and Cer(d18:1/22:0) are shown to be increased by 48, 40, and 33–folds respectively in infected plasma samples, and to 116, 91 and 50-folds in plasma samples with respiratory distress. Hence, monitoring of plasma ceramide concentration, targeting ceramide synthesis, its salvage and its regulatory mechanisms, are validated approach towards enhancing survival from Covid-19 respiratory distress.

Ceramide Levels and Covid-19 Respiratory Distress, a Causal Relationship

A causal relationship between plasma ceramide concentration and Covid-19 patients with respiratory distress symptoms is presented. Hence, monitoring of plasma ceramide concentration, targeting ceramide synthesis, its salvage and its regulatory mechanisms, are validated approach towards enhancing survival from Covid-19 respiratory distress. In this study, plasma samples of 52 individuals infected with Covid-19 were utilized in a lipidomic analysis. Lipids belonging to ceramide class exhibited a 400-fold increase in total plasma concentration in infected patients. Further analysis lead to demonstration of concentration dependency, for severe Covid-19 respiratory symptoms, in a subclass of ceramides. The subclasses Cer(d18:0/24:1), Cer(d18:1/24:1), and Cer(d18:1/22:0) are shown to be increased by 48, 40, and 33–folds respectively in infected plasma samples, and to 116, 91 and 50-folds in plasma samples with respiratory distress.

The particulars of certain drugs’ effect on the endogenous coenzyme Q10 plasma level in patients with cardiovascular diseases

ObjectivesCoenzyme Q10 (CoQ10) has many vital functions in human body and its endogenous level can be affected either by various diseases or by administrated drugs. This study reveals the effect of atorvastatin, amlodipine and ethoxidol on the endogenous CoQ10 plasma concentration.MethodsIt was determined the total plasma concentration of endogenous CoQ10 in the plasma of 54 healthy individuals and 62 patients with cardiovascular diseases during treatment with various drugs using high performance liquid chromatography with mass spectrometric detection (HPLC-MS/MS).ResultsIt was found that CoQ10 plasma concentration in patients is statistically significantly lower (on average −49.0 Δ%) than in practically healthy individuals. The total CoQ10 plasma level in patients receiving atorvastatin in the complex therapy is statistically significantly lower (−15.2 Δ%), and in patients taking amlodipine or ethoxidol is statistically significantly higher (+18.2 and + 20.2 Δ%, respectively) than in patients of control groups (a group of patients who receive the same drugs, except for the studied one).ConclusionsThe study showed that in patients with CVDs treated with various drugs the CoQ10 plasma level is statistically significantly lower than in practically healthy individuals. So, to avoid the adverse reactions connected with low CoQ10 plasma levels, it is recommended to adjust the therapy to maintain its constant level.

Pharmacokinetics of Lidocaine, Bupivacaine, and Levobupivacaine in Plasma and Brain in Awake Rats

Background We have compared the pharmacokinetics and brain distribution of lidocaine, racemic bupivacaine (bupivacaine), and levobupivacaine in awake, spontaneously breathing rats. Methods Lidocaine (0.5 mg x kg x min), bupivacaine (0.1 mg x kg x min), or levobupivacaine (0.1 mg x kg x min) was continuously administered to rats for 2 h (n = 12, each anesthetic). Blood samples and cerebral dialysate were collected during infusion and for 2 h after termination of infusion. Concentrations of anesthetics in the cerebral extracellular fluid were measured by microdialysis using the retrodialysis calibration method. Tissue-to-plasma partition coefficients calculated from the total (protein-bound and unbound) and unbound concentrations in plasma and brain as well as pharmacokinetic parameters in plasma and cerebral extracellular fluid were compared among the three anesthetics. Results There were no differences in plasma total or unbound concentrations between bupivacaine and levobupivacaine. Concentrations of bupivacaine in the cerebral extracellular fluid were significantly higher than levobupivacaine (P < 0.001). Despite no differences in the ratio of total brain concentration to total plasma concentration among the three anesthetics, the ratio of cerebral extracellular fluid concentration to plasma unbound fraction of bupivacaine was significantly higher than lidocaine and levobupivacaine (0.58 +/- 0.09, 0.47 +/- 0.18, and 0.40 +/- 0.09, respectively; P = 0.03 and 0.003, respectively). Conclusions Although the ratio of total brain concentration to total plasma concentrations of lidocaine, bupivacaine, and levobupivacaine was similar, concentration ratio of bupivacaine in the cerebral extracellular fluid to plasma unbound fraction was significantly higher than lidocaine and levobupivacaine.

Homocysteine Disulphides and Vascular Disease

The total plasma concentration of homocysteine is a marker of this amino acid's atherogenic potential. However, the homocysteine pool exists almost entirely as oxidized homocysteine equivalents (OHcyE), composed of homocystine and cysteine-homocysteine disulphides (20–30%), and protein-bound disulphide (70–80%). We have noticed that the total concentration of OHcyE in injured coronary artery tissue is higher than the aqueous solubility of homocystine (∼1.4–1.5 × 10-3mol kg-1versus ∼0.6 mol kg-1). Based on the measurement of the solubility of homocystine in a plasma-mimetic condition (0.17 mol kg-1NaCl at 37°C), we have estimated that OHcyE may really reach their saturation limit in the vascular tissue (0.93–1.02 × 10-3mol kg-1), above which their deposition as solid phase may occur. This means that significant leakage of intracellular fluid can promote OHcyE crystallization in tissue fluids, which may serve to initiate inflammation. We speculate that deposition of OHcyE crystals could damage blood vessels and act as a primer of homocysteine-triggered inflammation, thus being along the causal pathway that leads to vascular dysfunction.