Single-cell meta-analysis of SARS-CoV-2 entry genes across tissues and demographics

Angiotensin-converting enzyme 2 (ACE2) and accessory proteases (TMPRSS2 and CTSL) are needed for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cellular entry, and their expression may shed light on viral tropism and impact across the body. We assessed the cell-type-specific expression of ACE2, TMPRSS2 and CTSL across 107 single-cell RNA-sequencing studies from different tissues. ACE2, TMPRSS2 and CTSL are coexpressed in specific subsets of respiratory epithelial cells in the nasal passages, airways and alveoli, and in cells from other organs associated with coronavirus disease 2019 (COVID-19) transmission or pathology. We performed a meta-analysis of 31 lung single-cell RNA-sequencing studies with 1,320,896 cells from 377 nasal, airway and lung parenchyma samples from 228 individuals. This revealed cell-type-specific associations of age, sex and smoking with expression levels of ACE2, TMPRSS2 and CTSL. Expression of entry factors increased with age and in males, including in airway secretory cells and alveolar type 2 cells. Expression programs shared by ACE2+TMPRSS2+ cells in nasal, lung and gut tissues included genes that may mediate viral entry, key immune functions and epithelial-macrophage cross-talk, such as genes involved in the interleukin-6, interleukin-1, tumor necrosis factor and complement pathways. Cell-type-specific expression patterns may contribute to the pathogenesis of COVID-19, and our work highlights putative molecular pathways for therapeutic intervention.

The Human and Mouse Enteric Nervous System at Single-Cell Resolution

The enteric nervous system (ENS) coordinates diverse functions in the intestine but has eluded comprehensive molecular characterization because of the rarity and diversity of cells. Here we develop two methods to profile the ENS of adult mice and humans at single-cell resolution: RAISIN RNA-seq for profiling intact nuclei with ribosome-bound mRNA and MIRACL-seq for label-free enrichment of rare cell types by droplet-based profiling. The 1,187,535 nuclei in our mouse atlas include 5,068 neurons from the ileum and colon, revealing extraordinary neuron diversity. We highlight circadian expression changes in enteric neurons, show that disease-related genes are dysregulated with aging, and identify differences between the ileum and proximal/distal colon. In humans, we profile 436,202 nuclei, recovering 1,445 neurons, and identify conserved and species-specific transcriptional programs and putative neuro-epithelial, neuro-stromal, and neuro-immune interactions. The human ENS expresses risk genes for neuropathic, inflammatory, and extra-intestinal diseases, suggesting neuronal contributions to disease.

The human body at cellular resolution: the NIH Human Biomolecular Atlas Program

Transformative technologies are enabling the construction of three-dimensional maps of tissues with unprecedented spatial and molecular resolution. Over the next seven years, the NIH Common Fund Human Biomolecular Atlas Program (HuBMAP) intends to develop a widely accessible framework for comprehensively mapping the human body at single-cell resolution by supporting technology development, data acquisition, and detailed spatial mapping. HuBMAP will integrate its efforts with other funding agencies, programs, consortia, and the biomedical research community at large towards the shared vision of a comprehensive, accessible three-dimensional molecular and cellular atlas of the human body, in health and under various disease conditions.

Effect on oxidative stress, hepatic chemical metabolizing parameters, and genotoxic damage of mad honey intake in rats

A total of 66 male Wistar rats were used and six groups (control: 10 animals and experimental: 12 animals) were formed. While a separate control group was established for each study period, mad honey application to the animals in the experimental group was carried out with a single dose (12.5 g kg−1 body weight (b.w.); acute stage), at a dose of 7.5 g kg−1 b.w. for 21 days (subacute stage), and at a dose of 5 g kg−1 b.w. for 60 days (chronic stage). Tissue and blood oxidative stress markers (malondialdehyde (MDA), nitric oxide (NO), 4-hydroxynonenal (HNE), superoxide dismutase, catalase, glutathione (GSH) peroxidase, and glucose-6-phosphate dehydrogenase), hepatic chemical metabolizing parameters in the liver (cytochrome P450 2E1, nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase, nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome c reductase (CYTC), GSH S-transferase (GST), and GSH), and micronucleus and comet test in some samples were examined. Findings from the study showed that single and repeated doses given over the period increased MDA, NO, and HNE levels while decreasing/increasing tissue and blood antioxidant enzyme activities. From hepatic chemical metabolizing parameters, GST activity increased in the subacute and chronic stages and CYTC activity increased in the acute period, whereas GSH level decreased in the subacute stage. Changes in tail and head intensities were found in most of the comet results. Mad honey caused oxidative stresses for each exposure period and made some significant changes on the comet test in certain periods for some samples obtained. In other words, according to the available research results obtained, careless consumption of mad honey for different medical purposes is not appropriate.

Single-dose toxicokinetics of permethrin in broiler chickens

Single-dose toxicokinetics of permethrin was investigated in broiler chickens. A total of 20 male broiler chickens were assigned at random to two groups of 10 at 30 days of age. A single dose of 10 mg/kg body weight of permethrin was administered intravenously to the first group; in the second group, the same dose was administered into the crop. Serum permethrin was measured using an electron capture detector and gas chromatography equipment. The derived serum permethrin concentration/time curve demonstrated that the distribution kinetics of permethrin was well described by a two-compartment open model. For intravenous permethrin administration, the half-life at λ phase (t1/2λ), mean residence time (MRT) and area under the concentration-time curve in 0→∞ (AUC0→∞) values respectively were 4.73 ± 1.00 h, 5.06 ± 1.05 h and 16.45 ± 3.28 mg/h/l. In contrast, the Cmax, tmax, t1/2λ, MRT and AUC0→∞ values respectively of the group given intra-crop permethrin were 0.60 ± 0.42 μg/ml, 0.55 ± 0.19 h, 5.54 ± 0.78 h, 7.06 ± 0.63 h and 1.95 ± 0.97 mg/h/l. The bioavailability of permethrin was 0.11. For both administration routes, the residence time of permethrin in the body was short and the bioavailability of permethrin was low. These results are relevant for assessing the use and safety of permethrin.

Synergistic action of sodium selenite and N-acetylcysteine in acetaminophen-induced liver damage

Acetaminophen (AAP) is a commonly used analgesic and antipyretic drug; however, when used in high doses, it causes fulminant hepatic necrosis in both humans and experimental animals. In this study, we investigated whether selenium (Se) and N-acetylcysteine (NAC), alone or in combination, are protective against AAP toxicity in mice. At the beginning of the experiment, blood samples were taken from 10 of 350 mice. Then, the remaining mice were randomly allocated into four groups, each consisting of 35 animals. The 1st group received a single administration of AAP by gavage at a dose of 600 mg/kg-bw, p.o. The 2nd group (AAP-Se) was treated with sodium selenite (0.5 mg Se/kg-bw, p.o.) one hour after ingestion of AAP. The 3rd group (AAP-NAC) ingested AAP, 1.5 h later followed by NAC (500 mg/kg-bw, p.o.). The 4th group (AAP-Se-NAC) was given sodium selenite and NAC, 1 and 1.5 h after administration of AAP, respectively. From each group, blood samples of seven mice for each time point were taken at 4, 8, 24, and 48 h after AAP toxicity. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) levels were measured. Compared with AAP group, the levels of ALT were lower after AAP ingestion in AAP-NAC, AAP-Se, and AAP-Se-NAC groups at the 8th hour. ALT, AST, and LDH levels in AAP-Se-NAC group were 50% of the levels of other groups starting form the 4th hour of toxicity. It is concluded that protection against AAP hepatotoxicity using a combination of Se and NAC is better than that found with either agent alone.