Hydrogen sulfide produced by the gut microbiota impairs host metabolism via reducing GLP-1 levels in male mice.

Dysbiosis of the gut microbiota has been implicated in the pathogenesis of metabolic syndrome (MetS) and may impair host metabolism through harmful metabolites. Here, we show that Desulfovibrio, an intestinal symbiont enriched in patients with MetS, suppresses the production of the gut hormone glucagon-like peptide 1 (GLP-1) through the production of hydrogen sulfide (H2S) in male mice. Desulfovibrio-derived H2S is found to inhibit mitochondrial respiration and induce the unfolded protein response in intestinal L cells, thereby hindering GLP-1 secretion and gene expression. Remarkably, blocking Desulfovibrio and H2S with an over-the-counter drug, bismuth subsalicylate, improves GLP-1 production and ameliorates diet-induced metabolic disorder in male mice. Together, our study uncovers that Desulfovibrio-derived H2S compromises GLP-1 production, shedding light on the gut-relayed mechanisms by which harmful microbiota-derived metabolites impair host metabolism in MetS and suggesting new possibilities for treating MetS.

Synthesis, antimycobacterial evaluation, and molecular docking study of 1,2,4-triazole derivatives.

Fifteen 1,2,4-triazole derivatives were synthesised in this study and their MIC values against Mycobacterium tuberculosis (Mtb) ranged from 2 to 32 µg/mL. Furthermore, their antimycobacterial activity was positively correlated with the KatG enzyme docking score. Among the 15 compounds, compound 4 showed the strongest bactericidal activity with an MIC of 2 µg/mL. The selectivity index of compound 4 is more than 10, indicating that the compound has low toxicity to animal cells and has the potential to become a drug. Molecular docking indicates that compound 4 can bind firmly to the Mtb KatG active site. The experimental results showed that compound 4 inhibited Mtb KatG and caused the accumulation of ROS in Mtb cells. We speculate that compound 4 causes the accumulation of ROS by inhibiting KatG, and ROS produces oxidative destruction, leading to the death of Mtb. This study provides a new idea for the development of novel anti-Mtb drugs.

Antimycobacterial Compound of Cynoglossum lanceolatum Forsk.: Bioassay Guided Isolation, Molecular Docking, Synthesis of Analogs, and a Plausible Mechanism of Action.

Tuberculosis (TB) remains a major threat to human health. Due to the prevalence of drug-resistant Mycobacterium tuberculosis (Mtb), it is urgent to discover drugs with new mechanisms of action (MOA) to ensure effectiveness against strains that are resistant to existing TB drugs. Cynoglossum lanceolatum Forsk was used to treat TB in Traditional Chinese Medicine. In this article, shikonin, the anti-Mtb active component, was obtained from the whole herb extract of C. lanceolatum by bioassay-guided isolation. Using the microplate alamar blue assay (MABA), the minimum inhibitory concentration (MIC) of shikonin against Mtb was determined to be 128 µg/mL. In order to obtain a more efficient anti-Mtb molecule, (E)-1-(6-bromo-2,3-dihydrochromen-4-ylidene)thiosemicarbazide was synthesized based on the scaffold of shikonin, which exhibited potent activity against Mtb (MIC=4 µg/mL). These results highlight that both naphthalene-1,4-dione and chroman-4-one are pharmacophores with activities against Mtb. To investigate a plausible mechanism of action, the molecular docking was firstly performed against catalase-peroxidase enzyme (KatG) of Mtb using AutoDock 4 software. The results demonstrated that both shikonin and (E)-1-(6-bromo-2,3-dihydrochromen-4-ylidene)thiosemicarbazide could bind to the active site of Mtb KatG. KatG enzyme activity and intracellular reactive oxygen species (ROS) levels in Mtb cells were then measured by ultraviolet spectrophotometric method and fluorescence microplate reader assay, respectively. The experiments confirmed that above compounds could inhibit the catalytic activity of Mtb KatG, and cause the ROS accumulation in Mtb cells. Therefore, inhibition of KatG may be a novel mechanism of action for these two compounds to fight against Mtb.

Investigation of the hemostatic mechanism of Gardeniae fructus Praeparatus based on pharmacological evaluation and network pharmacology.

Background: As documented in the Chinese Pharmacopoeia, Gardeniae fructus Praeparatus (GFP) can cool the blood during hemostasis and treat various internal hemorrhagic diseases. However, the underlying mechanisms are not yet well understood. This work was designed to decipher the possible mechanism by which GFP prevents hemorrhage. The integration of pharmacodynamics-based and bioinformatics-based methods provided evidence to support the clinical effects of GFP in treating bleeding. Methods: Using ultra-performance liquid chromatography (UPLC) analysis, we quantified the main active ingredients for a preliminary quality assessment of GFP. The pharmacology study was conducted to confirm the essential antihemorrhagic effects of GFP. A rat model of ethanol-induced gastric hemorrhage was established and was followed by intervention with GFP in low, middle, and high doses (4.5, 9, 18 g/kg). Gastric tissues were harvested for macroscopic and histological evaluation of lesions. The contents of thromboxane B2 (TXB2) and 6-keto-prostaglandin-F1α (6-keto-PGF1α) in the serum were determined. Additionally, network pharmacology was proposed to illuminate the potential mechanisms. Following the collection of GFP compositions, the compound- and hemorrhage-related targets were retrieved from public databases. The protein-protein interaction (PPI), gene ontology, pathways analysis, and molecular docking were performed for targets of GFP in gastrointestinal bleeding. Results: The study found ten main active ingredients that could be used for quality control of GFP. Importantly, the middle and high doses of GFP were found to promote the healing of gastric bleeding. The content of 6-keto-PGF1α was significantly degraded in the middle and high treated groups (P<0.05). The level of TXB2 was augmented by a middle (P<0.05) and high dose of GFP. Further, we constructed the network of candidate ingredients and hemorrhage-related targets. Pathway analysis predicted the mechanisms associated with interleukin 4 and interleukin 13 signaling and platelet activation. PPI analysis identified subnetworks with biological functions and also sifted hub targets that affected the antihemorrhagic progress. The candidate proteins had a good binding force with major components. Conclusions: GFP exhibits a promising effect in ameliorating bleeding, with the relevant molecular mechanisms possibly being related to the regulation of the immune system and platelet activation. Therefore, GFP can potentially exert a protective effect on gastrointestinal bleeding in clinic.

A Novel Method for Quality Evaluation of Gardeniae fructus Praeparatus during Heat Processing Based on Sensory Characteristics and Chemical Compositions.

The intrinsic chemical components and sensory characteristics of Gardeniae fructus Praeparatus (GFP) directly reflect its quality and subsequently, affect its clinical curative effect. However, there is little research on the correlation between the appearance traits and chemical compositions of GFP during heat processing. In this study, the major components of five typical processed decoction pieces of GFP were determined. With the deepening of processing, the contents of geniposidic acid and 5-HMF gradually increased, while the contents of deacetyl-asperulosidic acid methyl ester, gardenoside, and two pigments declined. Moreover, the electronic eye, electronic tongue, and electronic nose were applied to quantify GFP's sensory properties. It was found that the chroma values showed a downward trend during the processing of GFP. The results of odor showed that ammonia, alkenes, hydrogen, and aromatic compounds were the material base for aroma characteristics. Complex bitterness in GF was more obvious than that in other GFP processed products. Furthermore, one mathematical model was established to evaluate the correlation between the sensory characteristics and chemical composition of GFP during five different stages. A cluster analysis and neural network analysis contributed to recognizing the processing stage of GFP. This study provided an alternative method for the exterior and interior correlation-based quality evaluation of herbs.

A New Species and New Record of Freshwater Turbellarians of the Genus Gieysztoria (Platyhelminthes: Rhabdocoela) from China.

A new species of Dalyelliidae, Gieysztoria pellucida Wang and You, is described based on material collected in southern China through an integrative approach combining morphological, histological, and molecular (18S and 28S rDNA) data. Gieysztoria pellucida sp. nov. is morphologically characterized by a fan-shaped (about 270° when pressed) stylet, consisting of 13 similar distal spines and a broad girdle without fenestrae region. This stylet is distinct from that of any other similar species in the Aequales group to which this species belongs. In addition, specimens identifiable as Gieysztoria garudae Van Steenkiste, Van Mulken, and Artois, 2012 were discovered from the same location as G. pellucida sp. nov. Gieysztoria garudae has previously been known only from India; the present study thus represents the first record of the species from China.

The combination of nanotechnology and traditional Chinese medicine (TCM) inspires the modernization of TCM: review on nanotechnology in TCM-based drug delivery systems.

Fast development of combination of nanotechnology with traditional Chinese medicine (TCM) broadens the field of application of TCM. Besides, it increases the research ideas and contributes to TCM modernization. As expected, TCM will be developed into the nanodrug delivery system by nanotechnology with careful design, which will enhance the medicinal value of TCM to cure and prevent disease based on benefits brought by nanometer scale. Here, formulations, relevant preparations methods, and characteristics of nano-TCM were introduced. In addition, the main excellent performances of nano-TCM were clearly elaborated. What is more, the review was intended to address the studies committed to application of nanotechnology in TCM over the years, including development of Chinese medicine active ingredients, complete TCM, and Chinese herbal compounds based on nanotechnology. Finally, this review discussed the safety of nano-TCM and presented future development trends in the way to realize the modernization of TCM. Overall, using the emerging nanotechnology in TCM is promising to promote progress of TCM in international platform. Recent researches on modernization of traditional Chinese medicine (TCM) urged by nanotechnology are introduced, and formulations, advantages, and applications of nano-TCM are reviewed to provide strong proofs.

[Quality changes of Gardeniae Fructus Praeparatus processed by different frying methods: a color-component correlation analysis].

The chromatic values of the broken-fried and single-fried Gardeniae Fructus Praeparatus(GFP) were measured by the color analyzer to analyze the color variation rule, and the contents of 10 main components were determined by ultra-high performance liquid chromatography(UPLC). The multivariate statistical analysis, Pearson correlation analysis, and discriminant analysis were conducted to investigate the color and components of GFP samples. The experimental results revealed that L~*, a~*, b~*, and E~*ab decreased continuously during processing, and the color of samples gradually deepened. The trend and range of chromatic values during broken-frying and single-frying processes were basically identical. Gardenoside, crocin-Ⅰ(C-Ⅰ), and crocin-Ⅱ(C-Ⅱ) showed an obviously downward trend, while the contents of geniposidic acid and 5-hydroxymethylfurfural(5-HMF) increased significantly. Shanzhiside, deacetyl-asperulosidic acid methyl ester, and geniposide(G2) showed a downward trend. Scandoside methyl ester rose first and fell later. Genipin-1-O-gentiobioside(G1) went through a decrease-increase-decrease trend. The change trends of component contents during broken-frying and single-frying processes were generally consistent, but the change range was different. Among all the components, scandoside methyl ester and G1 showed obvious change. Because of different stir-frying time, the change rate of each component content in the process of broken-frying was higher than that in single-frying process. Additionally, geniposidic acid, gardenoside, scandoside methyl ester, C-Ⅰ, C-Ⅱ, and 5-HMF exhibited a higher correlation with apparent color. On the basis of above findings, the discriminant function of two frying processes was established, which could be applied to the discrimination of broken-fried and single-fried samples. This study analyzed the dynamic quality change rule of GFP during broken-frying and single-frying processes based on color-component correlation analysis, and found the two methods showed consistent change trend, yet with slight difference in the quality of samples. This study can provide data support for the processing of GFP.