Assessing heavy metal contamination in Amomum villosum Lour. fruits from plantations in Southern China: Soil-fungi-plant interactions.

Amomum villosum Lour. fruit is a common healthy food widely cultivated in southern China. Heavy metal contamination of farmland soils has becomes a serious environmental concern in China. Heavy metals in soil can be introduced into the food chain and pose health risks to humans. However, microbial communities may play beneficial roles in plants grown in metal-polluted soils. This study aimed to assess the potential health risks of heavy metals in soils and A. villosum fruits from different production areas and to explore the soil-microbe-plant regulation pattern for heavy metals in A. villosum fruits. Soil and A. villosum fruit samples were collected from nine planting fields in four provinces of southern China. The results showed that soils from seven areas were polluted with heavy metals to different degrees. Cr and Mn were the most serious contaminating elements. However, the accumulation of heavy metals in A. villosum fruit was negligible with no expected human health risks. Partial least squares path analysis of structural equation modeling showed that the accumulation of heavy metals in A. villosum fruits was influenced by multiple factors. More importantly, the PLS-SEM revealed that the heavy metal content in A. villosum fruits was indirectly affected by soil heavy metals through the regulation of the microbial community. Furthermore, some fungal phyla (e.g., Ascomycota and Chytridiomycota) and genera (e.g., Mucor) were related to the heavy metal content in the soil and in A. villosum fruits. The results of this study verified that soil fungal community play an important role in the accumulation of heavy metals in A. villosum fruits. Using fungi provides a potential biological strategy for reducing the health risk posed by heavy metals in food.

[Mechanism of Tibetan medicine Ershiwuwei Songshi Pills in regulating intestinal flora and improving non-alcoholic steatohepatitis].

This study aimed to investigate the effect of Tibetan medicine Ershiwuwei Songshi Pills(ESP) on the intestinal flora of non-alcoholic steatohepatitis(NASH) mice. Forty-eight male C57 BL/6 mice were randomly divided into the control group, model(methionine-choline-deficient, MCD) group, high-(0.8 g·kg~(-1)), medium-(0.4 g·kg~(-1)), and low-dose(0.2 g·kg~(-1)) ESP groups, and pioglitazone(PGZ, 10 mg·kg~(-1)) group, with eight mice in each group. Mice in the control group were fed with normal diet, while those in the remaining five groups with MCD diet for five weeks for inducing NASH. During modeling, they were gavaged with the corresponding drugs. The changes in body mass, daily water intake, and daily food intake were recorded. At the end of the experiment, the liver tissues were collected and stained with hematoxylin-eosin(HE) for observing the pathological changes, followed by oil red O staining for observing fat accumulation in the liver. The levels of serum aspartate aminotransferase(AST) and alanine aminotransferase(ALT) and triglyceride(TG) in liver tissue were measured. The changes in intestinal flora of mice were determined using 16 S rRNA high-throughput sequencing technology. The results showed that compared with the model group, the high-, medium-and low-dose ESP groups and the PGZ group exhibited significantly lowered AST and ALT in serum and TG in liver tissues and alleviated hepatocellular steatosis and fat accumulation in the liver. As demonstrated by 16 S rRNA sequencing, the abundance index and diversity of intestinal flora decreased in the model group, while those increased in the ESP groups. Besides, the Firmicutes to Bacteroidetes ratio decreased at the phylum level. In the alteration of the composition of intestinal flora, ESP reduced the abundance of Erysipelotrichia and Faecalibaculum but increased the abundance of Desulfovibrionaceae, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae. This study has revealed that ESP has a protective effect against NASH induced by MCD diet, which may be related to its regulation of the changes in intestinal flora, alteration of the composition of intestinal flora, and inhibition of the intestinal dysbiosis.

[Serum metabolomics of Tibetan medicine Ershiwuwei Songshi Pills against chronic cholestasis in mice].

A chronic cholestasis model was induced in mice by feeding a diet containing 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine(DDC). The effects of Ershiwuwei Songshi Pills(ESP) on endogenous metabolites in mice with chronic cholestasis were investigated by metabolomics analysis based on liquid chromatography-mass spectrometry(LC-MS). The results showed that ESP was effective in improving pathological injury and reducing serum levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP), and total bile acid in the model mice. Meanwhile, 13 common differential metabolites were revealed in metabolomic screening between the model/control group and the model/ESP group, including uric acid, glycolaldehyde, kynurenine, flavin adenine dinucleotide, L-3-phenyllactic acid, I-urobilin, leukotriene D4(LTD4), taurocholic acid, trioxilin A3, D-inositol-1,4-diphosphate, PC [16:0/20:2(11Z,14Z)], PC[14:0/22:2(13Z,16Z)], and PC[20:4(5Z,8Z,11Z,14Z)/20:4(5Z,8Z,11Z,14Z)]. After ESP intervention, the levels of all 13 differential metabolites were significantly retraced, and pathway analysis showed that ESP achieved its therapeutic effect mainly by affecting arachidonic acid metabolism, glycerophospholipid metabolism, tryptophan metabolism, and primary bile acid biosynthesis. This study elucidated the mechanism of action of ESP against chronic cholestasis based on metabolites.

A potent human monoclonal antibody with pan-neutralizing activities directly dislocates S trimer of SARS-CoV-2 through binding both up and down forms of RBD.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of novel coronavirus disease (COVID-19). The neutralizing monoclonal antibodies (mAbs) targeting the receptor-binding domain (RBD) of SARS-CoV-2 are among the most promising strategies to prevent and treat COVID-19. However, SARS-CoV-2 variants of concern (VOCs) profoundly reduced the efficacies of most of mAbs and vaccines approved for clinical use. Herein, we demonstrated mAb 35B5 efficiently neutralizes both wild-type (WT) SARS-CoV-2 and VOCs, including B.1.617.2 (delta) variant, in vitro and in vivo. Cryo-electron microscopy (cryo-EM) revealed that 35B5 neutralizes SARS-CoV-2 by targeting a unique epitope that avoids the prevailing mutation sites on RBD identified in circulating VOCs, providing the molecular basis for its pan-neutralizing efficacy. The 35B5-binding epitope could also be exploited for the rational design of a universal SARS-CoV-2 vaccine.

Cross-Species Annotation of Expressed Genes and Detection of Different Functional Gene Modules Between 10 Cold- and 10 Hot-Propertied Chinese Herbal Medicines.

According to the traditional Chinese medicine (TCM) system, Chinese herbal medicines (HMs) can be divided into four categories: hot, warm, cold, and cool. A cool nature usually is categorized as a cold nature, and a warm nature is classified as a hot nature. However, the detectable characteristics of the gene expression profile associated with the cold and hot properties have not been studied. To address this question, a strategy for the cross-species annotation of conserved genes was established in the present study by using transcriptome data of 20 HMs with cold and hot properties. Functional enrichment analysis was performed on group-specific expressed genes inferred from the functional genome of the reference species (i.e., Arabidopsis). Results showed that metabolic pathways relevant to chrysoeriol, luteolin, paniculatin, and wogonin were enriched for cold-specific genes, and pathways of inositol, heptadecane, lauric acid, octanoic acid, hexadecanoic acid, and pentadecanoic acid were enriched for hot-specific genes. Six functional modules were identified in the HMs with the cold property: nucleotide biosynthetic process, peptidy-L-cysteine S-palmitoylation, lipid modification, base-excision repair, dipeptide transport, and response to endoplasmic reticulum stress. For the hot HMs, another six functional modules were identified: embryonic meristem development, embryonic pattern specification, axis specification, regulation of RNA polymerase II transcriptional preinitiation complex assembly, mitochondrial RNA modification, and cell redox homeostasis. The research provided a new insight into HMs' cold and hot properties from the perspective of the gene expression profile of plants.

Threonine ADP-Ribosylation of Ubiquitin by a Bacterial Effector Family Blocks Host Ubiquitination.

Ubiquitination is essential for numerous eukaryotic cellular processes. Here, we show that the type III effector CteC from Chromobacterium violaceum functions as an adenosine diphosphate (ADP)-ribosyltransferase that specifically modifies ubiquitin via threonine ADP-ribosylation on residue T66. The covalent modification prevents the transfer of ubiquitin from ubiquitin-activating enzyme E1 to ubiquitin-conjugating enzyme E2, which inhibits subsequent ubiquitin activation by E2 and E3 enzymes in the ubiquitination cascade and leads to the shutdown of polyubiquitin synthesis in host cells. This unique modification also causes dysfunction of polyubiquitin chains in cells, thereby blocking host ubiquitin signaling. The disruption of host ubiquitination by CteC plays a crucial role in C. violaceum colonization in mice during infection. CteC represents a family of effector proteins in pathogens of hosts from different kingdoms. All the members of this family specifically ADP-ribosylate ubiquitin. The action of CteC reveals a new mechanism for interfering with host ubiquitination by pathogens.

How Do Structurally Distinct Compounds Exert Functionally Identical Effects in Combating Obesity?

Although the concept of inflammatory obesity remains to be widely accepted, a plethora of antibiotics, anti-inflammatory agents, mitochondrial uncouplers, and other structurally distinct compounds with unknown mechanisms have been demonstrated to exert functionally identical effects on weight reduction. Here we summarize a universal mechanism in which weight loss is modulated by mitochondrial biogenesis, which is correlated with conversion from the mitochondria-insufficient white adipose tissue to the mitochondria-abundant brown adipose tissue. This mechanistic description of inflammatory obesity may prove useful in the future for guiding pathology-based drug discovery for weight reduction.

Emergence and genomic analysis of MDR Laribacter hongkongensis strain HLGZ1 from Guangzhou, China.

Background: Laribacter hongkongensis is a facultative anaerobic, non-fermentative, Gram-negative bacillus associated with community-acquired gastroenteritis and traveller's diarrhoea. No clinical MDR L. hongkongensis isolate has been reported yet. Methods: We performed WGS (PacBio and Illumina) on a clinical L. hongkongensis strain HLGZ1 with an MDR phenotype. Results: HLGZ1 was resistant to eight classes of commonly used antibiotics. Its complete genome was a single circular chromosome of 3 424 272 bp with a G + C content of 62.29%. In comparison with the reference strain HLHK9, HLGZ1 had a higher abundance of genes associated with DNA metabolism and recombination. Several inserts including two acquired resistance gene clusters (RC1 and RC2) were also identified. RC1 carried two resistance gene cassette arrays, aac(6')-Ib-cr-aadA2-Δqac-Δsul1-floR-tetR-tetG and arr-3-dfrA32-ereA2-Δqac-sul1, which shared significant nucleotide sequence identities with the MDR region of Salmonella Genomic Island 1 from Salmonella enterica serovar Typhimurium DT104. There was also an integron-like structure, intl1-arr3-dfrA27-Δqac-sul1-aph(3')-Ic, and a tetR-tetA operon located on RC2. MLST analysis identified HLGZ1 as ST167, a novel ST clustered with two strains previously isolated from frogs. Conclusions: This study provides insight into the genomic characteristics of MDR L. hongkongensis and highlights the possibilities of horizontal resistance gene transfer in this bacterium with other pathogens.

Poor and enantioselective bioavailability of naftopidil enantiomers is due to extensive and stereoselective metabolism in rat liver.

Racemic naftopidil (NAF) is used to treat benign prostatic hyperplasia (BPH) and prostatic cancer (PCa). It exhibits greater efficacy but requires higher dose than other ɑ1-adrenoceptor blockers because of its poor bioavailability. It was previously shown that bioavailability of S(-)-NAF (14.5%) was twice that of R(+)-NAF (6.8%). The present study aimed to elucidate the major factors contributing to the poor and enantioselective bioavailability of NAF. First, absorption of NAF enantiomers was examined using a perfusated intestinal model. NAF enantiomers were found to be equally and highly permeable in all segments of the intestine. Second, the metabolites formed in different parts of the intestine and in bile were investigated. Glucuronidation of NAF enantiomers was found to occur primarily in the liver. Third, a new method consisting of ultra performance liquid chromatography coupled with triple-quadruple mass spectrometry (UPLC-MS/MS) was employed to quantify and calculate the pharmacokinetic parameters of NAF enantiomers and their glucuronides after the enantiomers were intravenously injected into rats. The amounts of R(+)-NAF glucuronide (R(+)-NAF-G) and S(-)-NAF glucuronide (S(-)-NAF-G) were six-fold higher than that of R(+)-NAF, and three-fold higher than that of S(-)-NAF. Glucuronidation of S(-)-NAF was faster than that of R(+)-NAF, but the conjugated amount was half of that of R(+)-NAF. Thus, bioavailability of S(-)-NAF was twice that of R(+)-NAF. In conclusion, extensive phase II metabolism in the liver significantly contributes to the low bioavailability of NAF enantiomers. Glucuronidation is the most important metabolic pathway for NAF enantiomers. Glucuronidation of S(-)-NAF is faster but occurs to a lesser extent than that of R(+)-NAF.

Structural basis of Cas3 inhibition by the bacteriophage protein AcrF3.

Bacteriophages express proteins that inactivate the CRISPR-Cas bacterial immune system. Here we report the crystal structure of the anti-CRISPR protein AcrF3 in complex with Pseudomonas aeruginosa Cas3 (PaCas3). AcrF3 forms a homodimer that locks PaCas3 in an ADP-bound form, blocks the entrance of the DNA-binding tunnel in the helicase domain, and masks the linker region and C-terminal domain of PaCas3, thereby preventing recruitment by Cascade and inhibiting the type I-F CRISPR-Cas system.

[Pharmacokinetic Study on Brucine in Different Administration Methods of Liposome in Rats].

OBJECTIVE: To compare the pharmacokinetic differences of brucine in rats after different administration methods of brucine liposome. METHODS: To determine brucine in rat plasma at different points in time by HPLC after oral administration, intramuscular injection, subcutaneous injection and intravenous injection of brucine liposome, respectively. The pharmacokinetic parameters were calculated and analyzed by DAS 3.0. RESULTS: Compared with other groups, AUC(0 --> t) of subcutaneous injection were higher, C(max) were lower and MRT(0 --> 1), were significantly improved. The pharmacokinetics parameters and absolute bioavailability of brucine show that bioavailability in rats after different administration methods of brucine liposome is subcutaneous injection > intramuscular injection > oral administration.

[In vivo Pharmacokinetics of Notoginsenoside R1 in Ischemia Rats After Acute Myocardial Infarction].

OBJECTIVE: To establish an HPLC-UV method for determining pharmacokinetic difference of notoginsenoside R1 between normal rats and ischemic rats. METHODS: 48 male SD rats were randomly divided into normal group and acute myocardial ischemia( AMI) model group induced by pituitrin and each group was classified into high,middle and low-dose of groups with notoginsenoside R1 (200, 100 and 50 mg/kg) respectively. Blood samples were collected at different points in time after they were administered once by gavage and separated by Waters symmetry C18 column (250 mm x 4.6 mm, 5 µm) under the detective wavelength 203 nm, the mobile phase was acetonitrile-water with icariin as the internal standard and the pharmacokinetic parameters were calculated by DAS 2. 0. RESULTS: Notoginsenoside R1 had good linearity in the ranges of 0.2~125 µg/mL (R2 = 0.9997) with SNR 1:3 and the lowest detection limit was 0.053 µg/mL, the extraction rate, RSDs of within-day and between-day, specificity, accuracy and precision accorded with the require-ment of bio-sample pretreatment. Compared to the normal group, AUC0-t, and AUC0-∞ was significantly increased (P < 0.01) and the terminal half-life was prolonged markedly (P < 0.01) in AMI group. CONCLUSIONS: The method is simple, accurate and had high specificity and sensitivity, that could be applied in quantitative determination of notoginsenoside R1 and research of pharmacokinetics; the relative bioavailability of notoginsenoside R1 is increased significantly in AMI group,which indicates that notoginsenoside R1 has better effect in model rat.