Flavonoids from Rhododendron nivale Hook. f delay aging via modulation of gut microbiota and glutathione metabolism.

BACKGROUND: Rhododendron nivale Hook. f (R.n), one of the four Manna Stash used in Tibetan medicine to delay aging, possesses anti-aging pharmacological activity. However, which R.n ingredients contain anti-aging properties and the underlying mechanisms involved are unclear. HYPOTHESIS/PURPOSE: Based on interactions between gut microbiota and natural medicines and the important role of gut microbiota in anti-aging, the study investigated the hypothesis that R.n possesses anti-aging properties and the interaction of gut microbiota with R.n is responsible for its anti-aging effects. STUDY DESIGN: The primary active ingredients of R.n and their target function and pathway enrichment were explored. An aging mouse model was used to clarify the underlying anti-aging mechanisms of R.n. METHODS: Chromatography, spectroscopy, nuclear magnetic technology, and pharmacology were used to reveal the major active ingredients of ethanol extract residues of R.n (RNEA). The target function and pathway enrichment of these active ingredients were explored. Plasma metabolomics coupled with intestinal flora evaluation and bioinformatics analysis was used to clarify the underlying anti-aging mechanisms of RNEA. RESULTS: Myricetin-3-ß-D-xylopyranoside, hyperin, goospetin-8-methyl ether 3-ß-D-galactoside, and diplomorphanin B were separated and identified from RNEA. The network pharmacology study revealed that the active ingredients' target function and pathway enrichment focused mainly on the glutathione antioxidant system. In a D-galactose-induced mouse model of aging, RNEA was shown to possess suitable anti-aging pharmacological activity, as indicated by the amelioration of memory loss and weakened superoxide dismutase and glutathione peroxidase activities. Plasma metabolomics coupled with intestinal flora examination and bioinformatics analysis revealed that RNEA could regulate the expression of glutathione-related enzymes and ameliorate D-galactose-induced imbalances in methionine, glycine, and serine, and betaine and galactose metabolism. The results showed that RNEA reshaped the disordered intestinal flora and mitigated the D-galactose-mediated decline in glutathione oxidase expression, further confirming that the anti-aging effect of RNEA was closely related to regulation of the glutathione antioxidant system. CONCLUSION: RNEA, consisting of myricetin-3-ß-D-xylopyranoside, hyperin, goospetin-8-methyl ether 3-ß-D-galactoside, and diplomorphanin B, possesses anti-aging activity. The anti-aging effect of RNEA might be due to reshaping intestinal flora homeostasis, increasing the expression of glutathione peroxidase 4 in the intestines and liver, enhancing glutathione peroxidase activity, and reinforcing the glutathione antioxidant system.

[Analysis of the principles of Tibetan medicine processing].

Tibetan medicine processing ensures the safety of clinical application of Tibetan medicine. It is of great significance to analyze the principles of Tibetan medicine processing in the development, inheritance, and innovation of Tibetan medicine. However, due to the late start of modern Tibetan medicine research and the disciplinary division, the current research on Tibetan medicine processing focuses on the exploration and collation of traditional techniques and the analysis of the processing mechanism of Tibetan medicine through chemical and pharmacological research, but its principles and traditional theories have been rarely reported. In view of this, after analyzing the concept, essence, theories, purposes, and functions of Tibetan medicine processing through the integration of Tibetan medicine, Tibetan pharmacology, and clinical research of Tibetan medicine, this study proposed that the essence of Tibetan medicine processing was to change the "five sources" composition of medicinal materials through physical, chemical, and biological means, or the comprehensive means, and the theoretical principle of Tibetan medicine processing was to change or transform the positive and adverse effects or the obvious and recessive effects by altering the "five sources" composition of the drug to maximize the positive effect and minimize the adverse effect and the damage to the body, thereby achieving the purposes of toxicity reduction, efficacy enhancement, and drug property harmonization represented by sharpening, softening, nourishing, and reasonable compatibility. This study is expected to provide references for the construction of the theoretical system of Tibetan medicine processing, the inheritance of processing techniques, and innovative research.

Characterization of the complete chloroplast genome of the prickly blue poppy Meconopsis horridula Hook. f. & Thomson (Ranunculales: Papaveraceae).

The prickly blue poppy (Meconopsis horridula Hook. f. & Thomson) is a traditional Tibetan medicinal herb with high values. In this study, its chloroplast genome was determined to be 153,761 bp in length with an A + T-biased base composition, and comprises a pair of inverted repeat (IR) regions (26,030 bp), separated by a large single-copy (LSC) region (83,803 bp) and a small single-copy (SSC) region (17,898 bp). A total of 113 gene species were annotated, with 20 of them being completely or partially duplicated and 18 of them harboring one or two introns. Phylogenetic analysis suggests that M. horridula is closely related to Meconopsis racemosa Maxim.

Characterization of the complete chloroplast genome of the Musk Larkspur Delphinium brunonianum (Ranunculales: Ranunculaceae).

Musk Larkspur (Delphinium brunonianum) is a perennial herb of the family Ranunculace with medicinal values. In this study, the chloroplast (cp) genome of this herb was determined to be 153,926 bp long with an A + T-biased base composition, and comprises a pair of inverted repeat (IR) regions (26,559 bp), separated by a large single-copy (LSC) region (84,512 bp) and a small single-copy (SSC) region (16,296 bp). A total of 112 gene species were annotated with 19 of them being completely or partially duplicated. Eighteen gene species harbor one or two introns. Phylogenetic analysis challenged the monophyly of the subfamily Ranunculoideae.

Characterization of the complete chloroplast genome of the Tangut monkshood Aconitum tanguticum (Ranunculales: Ranunculaceae).

The Tangut monkshood (Aconitum tanguticum) is a perennial herb with high medicinal values. Here, its chloroplast genome was assembled from Illumina sequencing reads. The circular genome is 157,114 bp long with an A + T-biased nucleotide composition, and comprises a pair of inverted repeat (IR) regions (26,255 bp), separated by a large single-copy (LSC) region (87,559 bp) and a small single-copy (SSC) region (17,045 bp). It encodes a total of 112 gene species, with 19 of them being completely or partially duplicated and 18 of them harboring one or two introns. Phylogenetic analysis recovered two major clades of the genus Aconitum.

Characterization of the complete chloroplast genome of Impatiens alpicola (Balsaminaceae: Impatiens), a rare and endemic Chinese flowering plant.

Impatiens alpicola is a newly recorded rare and endemic flowering plant in China, which has been regarded as threatened due to its narrow distribution and human activity. In this study, its complete chloroplast genome was assembled from the whole genome Illumina sequencing data. The circular genome was 151,366 bp long, containing a large single copy (LSC) region of 82,245 bp and a small single copy (SSC) region of 17,705 bp, which were separated by a pair of 25,708 bp inverted repeat (IR) regions. It encoded a total of 128 genes, including 76 protein-coding genes, 44 tRNA genes and eight rRNA genes. The most of gene species occurred as a single copy, while 18 gene species occurred in double copies. The overall A + T content was 63.1%, while the corresponding values of the LSC, SSC and IR regions were 65.4, 70.6, and 56.9%, respectively. Phylogenetic analysis indicated that I. alpicola was relatively close to another species (I. piufanensis) belonging to the same genus.