Comparison of longitudinal SARS-CoV-2 nasopharyngeal specimens reveals the transcriptomic COVIDome

Introduction/Objective

SARS-Cov-2 is well established to introduce a cytokine-like storm among select individuals that results in multisystem failure and death. Comorbidities, age, oxygen status, and real-time appraisal of inflammatory markers in the blood have been used to risk stratify patients, however, these clinical markers do not comprehensively characterize the at-risk population or disease course. To understand the molecular underpinnings of the primary site of SARS-CoV-2 infection, here, we interrogated the transcriptomic profile of the nasopharyngeal tissue among paired SARS-CoV-2 specimens.

Methods/Case Report

We performed ribosomal depletion RNAseq on 24 primary samples, including 16 paired samples from 8 unique patients who converted between SARS-CoV-2 negative and positive status via clinical diagnostic qRT-PCR. Additional targeted qRT-PCR was performed for ACE2 and TMPRSS2 in an extension sample of 54 paired specimens from 27 unique patients who converted in their SARS-CoV-2 status on the basis of the qRT- PCR test. Differential gene expression, differential correlative expression with ACE2, and correlative expression with viral load was used to identify genes, which were integral to SARS-CoV-2 pathogenesis, so termed the COVIDome. Gene ontologies, pathways, and reactive infiltrate was assessed between specimens and compared with measures of clinical outcome using regression with appropriate correction for multiple hypotheses.

Results (if a Case Study enter NA)

We observed significant enrichment for ontologies of lymphocyte activation, specifically interferon gamma signaling; (P<1E-20) and platelet activation (P<1E-5). Genes specifically enriched across all three modules included: ADAMDEC1, EPSTI1, GRIP2, IRF7, KLHDC7B, OAS3, OASL, PIK3R4, RSAD2, and XAF1. Using CIBERSORT to approximate immune cell populations from bulk RNA, we observed and enrichment for CD4 immune cells, which was associated with viral status (P<0.01) while high-risk gene signatures were associated with measures of clinical outcome (P<0.05).

Conclusion

We characterized the pathogenesis of SARS-CoV-2 in longitudinal nasopharyngeal samples of COVID- 19 patients and related these molecular manifestations with measures of clinical outcome. As proof of principal, our findings suggest additional study in a large, longitudinal extension sample is warranted to validate and assess molecular features of clinical outcome associated with SARS-CoV-2 infection.

Hypersensitivity to amphetamine's psychomotor and reinforcing effects in serotonin transporter knockout rats: Glutamate in the nucleus accumbens

Background and Purpose

Amphetamine (AMPH) use disorder is a serious health concern, but, surprisingly, little is known about the vulnerability to the moderate and compulsive use of this psychostimulant and its underlying mechanisms. Previous research showed that inherited serotonin transporter (SERT) down‐regulation increases the motor response to cocaine, as well as moderate (as measured during daily 1‐h self‐administration sessions) and compulsive (as measured during daily 6‐h self‐administration sessions) intake of this psychostimulant. Here, we sought to investigate whether these findings generalize to AMPH and the underlying mechanisms in the nucleus accumbens.

Experimental Approach

In serotonin transporter knockout (SERT^−/−) and wild‐type control (SERT^+/+) rats, we assessed the locomotor response to acute AMPH and i.v. AMPH self‐administration under short access (ShA: 1‐h daily sessions) and long access (LgA: 6‐h daily sessions) conditions. Twenty‐four hours after AMPH self‐administration, we analysed the expression of glutamate system components in the nucleus accumbens shell and core.

Key Results

We found that SERT^−/− animals displayed an increased AMPH‐induced locomotor response and increased AMPH self‐administration under LgA but not ShA conditions. Further, we observed changes in the vesicular and glial glutamate transporters, NMDA and AMPA receptor subunits, and their respective postsynaptic scaffolding proteins as function of SERT genotype and AMPH exposure (baseline, ShA, and LgA), specifically in the nucleus accumbens shell.

Conclusion and Implications

We demonstrate that SERT gene deletion increases the psychomotor and reinforcing effects of AMPH and that the latter is potentially mediated, at least in part, by homeostatic changes in the glutamatergic synapse of the nucleus accumbens shell and/or core.

Pro-cognitive activity in rats of 3-furan-2-yl-N-p-tolyl-acrylamide, a positive allosteric modulator of the α7 nicotinic acetylcholine receptor

BACKGROUND AND PURPOSE

α7 nicotinic acetylcholine receptors (α7 nAChRs) may represent useful targets for cognitive improvement. The aim of this study is to compare the pro-cognitive activity of selective α7-nAChR ligands, including the partial agonists, DMXBA and A-582941, as well as the positive allosteric modulator, 3-furan-2-yl-N-p-tolyl-acrylamide (PAM-2).

EXPERIMENTAL APPROACH

The attentional set-shifting task (ASST) and the novel object recognition task (NORT) in rats, were used to evaluate the pro-cognitive activity of each ligand [i.e., PAM-2 (0.5, 1.0, and 2.0 mg·kg(-1) ), DMXBA and A-582941 (0.3 and 1.0 mg·kg(-1) )], in the absence and presence of methyllycaconitine (MLA), a selective competitive antagonist. To determine potential drug interactions, an inactive dose of PAM-2 (0.5 mg·kg(-1) ) was co-injected with inactive doses of either agonist - DMXBA: 0.1 (NORT); 0.3 mg·kg(-1) (ASST) or A-582941: 0.1 mg·kg(-1) .

KEY RESULTS

PAM-2, DMXBA, and A-582941 improved cognition in a MLA-dependent manner, indicating that the observed activities are mediated by α7 nAChRs. Interestingly, the co-injection of inactive doses of PAM-2 and DMXBA or A-582941 also improved cognition, suggesting drug interactions. Moreover, PAM-2 reversed the scopolamine-induced NORT deficit. The electrophysiological results also support the view that PAM-2 potentiates the α7 nAChR currents elicited by a fixed concentration (3 μM) of DMXBA with apparent EC50 = 34 ± 3 μM and Emax = 225 ± 5 %.

CONCLUSIONS AND IMPLICATIONS

Our results support the view that α7 nAChRs are involved in cognition processes and that PAM-2 is a novel promising candidate for the treatment of cognitive disorders.

Analgesic and sedative activities of lactucin and some lactucin-like guaianolides in mice

Lactucin (1) and its derivatives lactucopicrin (2) and 11beta,13-dihydrolactucin (3), which are characteristic bitter sesquiterpene lactones of Lactuca virosa and Cichorium intybus, were evaluated for analgesic and sedative properties in mice. The compounds showed analgesic effects at doses of 15 and 30 mg/kg in the hot plate test similar to that of ibuprofen, used as a standard drug, at a dose of 30 mg/kg. The analgesic activities of the compounds at a dose of 30 mg/kg in the tail-flick test were comparable to that of ibuprofen given at a dose of 60 mg/kg. Lactucopicrin appeared to be the most potent analgetic of the three tested compounds. Lactucin and lactucopicrin, but not 11beta,13-dihydrolactucin, also showed sedative properties in the spontaneous locomotor activity test.

Exogenous and endogenous ghrelin in gastroprotection against stress-induced gastric damage

Ghrelin, identified in the gastric mucosa has been involved in control of food intake and growth hormone (GH) release but little is known about its influence on gastric secretion and mucosal integrity. The effects of ghrelin on gastric secretion, plasma gastrin and gastric lesions induced in rats by 75% ethanol or 3.5 h of water immersion and restraint stress (WRS) were determined. Exogenous ghrelin (5, 10, 20, 40 and 80 microg/kg i.p.) increased gastric acid secretion and attenuated gastric lesions induced by ethanol and WRS and this was accompanied by the significant rise in plasma ghrelin level, gastric mucosal blood flow (GBF) and luminal NO concentrations. Ghrelin-induced protection was abolished by vagotomy and attenuated by suppression of COX, deactivation of afferent nerves with neurotoxic dose of capsaicin or CGRP(8-37) and by inhibition of NOS with L-NNA but not influenced by medullectomy and administration of 6-hydroxydopamine. We conclude that ghrelin exerts a potent protective action on the stomach of rats exposed to ethanol and WRS, and these effects depend upon vagal activity, sensory nerves and hyperemia mediated by NOS-NO and COX-PG systems.

Ghrelin-a new gastroprotective factor in gastric mucosa

Ghrelin, a novel peptide expressed in the gastrointestinal tract, especially in the gastric mucosa, exerts several biological activities including the stimulation of appetite and food intake, the stimulation of intestinal motility and the release of growth hormone. The aim of this study was to examine the expression of ghrelin in gastric mucosa after its exposure to ethanol and its effects on gastric lesions induced by ethanol with and without pretreatment with indomethacin. Acute gastric lesions were induced by intragastric administration of 75% ethanol in rats pretreated with saline-vehicle or ghrelin injected intraperitoneally (i.p.) without or with i.p. pretreatment with indomethacin. At the end of experiments, the rats were anesthetized, the stomach was exposed to measure gastric blood flow (GBF), to determine the area of gastric lesions and to take biopsy samples from the oxyntic mucosa for determination of transcripts of ghrelin, tumor necrosis alpha (TNF-alpha) and transforming growth factor alpha (TGFalpha) using RT-PCR and to assess the generation of PGE(2) by RIA. Exposure of gastric mucosa to 75% ethanol resulted in numerous mucosal lesions of an area of about 115 mm(2) and in the increase of mucosal expression of TNF-alpha, PGE(2), TGFalpha and ghrelin with concomitant decrease in GBF. Exogenous ghrelin reduced dose-dependently acute gastric lesions with simultaneous attenuation of GBF and a decrease in the expression of TNF-alpha but not TGFalpha. Pretreatment with indometahcin, which suppressed the generation of PGE(2) by about 85%, augmented ethanol-induced gastric lesions and eliminated the ghrelin-induced protection of mucosa against ethanol. We conclude that ghrelin, whose mucosal expression is enhanced after exposure to ethanol, exhibits a strong gastroprotection, at least in part, due to its anti-inflammatory action mediated by prostaglandins.

Biochemical and morphological study on liver Golgi complex in streptozotocin-diabetic and control rats treated with bis(kojato)oxovanadium(IV) [VO(ka)2]x2H2O. Part I. One week treatment with vanadium compound

In comparison with untreated control, reduced body and liver weights were found in two groups of rats (such as control and STZ-diabetic) treated orally with bis(kojato)oxovanadium(IV) solution. Free blood sugar in STZ-diabetic rats was lower by about 38%, but did not achieve euglycemic values. Yields of Golgi-rich fraction were lower than those in untreated controls, similar to the activity of galactosyl transferase (GalT) in both vanadium treated groups (control and diabetic). Under electron microscope in the control kojate-treated group, subcellular changes were observed. The morphology of Golgi apparatus was typical, resembled that in untreated animals. In diabetic animals treated with kojate subcellular changes were less severe. Golgi apparatus was usually semicircular or arched in shape similar to that observed previously in diabetic untreated rats.