Biology subjects

Liu, C.-F.

Publications and source records attributed to Liu, C.-F..

4 recordsLinked to original sources

bioRxiv2023

Decoding the Cure-all Effects of Ginseng

Ginseng has been known as a "cure-all" traditional medicine to treat various illnesses and as an adaptogen to relieve stress. However, the known active compounds of ginseng are small-molecule metabolites. Here we report ginsentides, which are disulfide-dense, super-stable and cell-penetrating peptides with 31-33 amino acids, as active compounds and adaptogens that restore homeostasis in response to stress. Using mass spectrometry-based target identification and functional studies, we show that ginsentides promote vasorelaxation by producing nitric oxide through endothelial cells via the PI3K/Akt signaling pathway. Ginsentides were also found to alleviate 1-adrenergic receptor overactivity by reversing phenylephrine-induced constriction of the aorta, decrease monocyte adhesion to endothelial cells via CD166/ESAM/CD40, inhibit P2Y12 receptors, reduce platelet aggregation, and thrombus formation in the lung. Orally administered ginsentides were effective in anti-stress behavior using animal models of tail suspension and forced swimming tests. Together, these results suggest that ginsentides interact with multiple systems to restore homeostasis by reversing stress-induced physiological changes and provide new insights into the panacea medicinal effects of ginseng.

pharmacology and toxicology↗

bioRxiv2022

Substrate-binding Glycine Residues are Major Determinants for Hydrolase and Ligase Activity of Plant Legumains

Peptide asparaginyl ligases (PALs) are Asn/Asp(Asx)-specific ligases that are useful for precision modifications of proteins and live-cell surfaces. However, PALs share high structural similarity to the far more common asparaginyl endopeptidases (AEPs), also known as legumains that hydrolyze peptide bonds after Asx, thus making it challenging to identify PALs in a sea of AEPs. Previously we identified sequences flanking the catalytic site as ligase activity determinants (LADs) for legumains. Here we show that two conserved substrate-binding Gly residues are critical, but negative determinants for ligase activity, based on a combined bioinformatics analysis of 1,500 plant legumains, mutagenesis and functional study of 16 novel legumains, plus identification of seven new PALs. We also show that PALs are rare and AEPs are much more common, accounting for about 1% and 88%, respectively. Our results suggest that specific glycine residues are molecular determinants to identify PALs and AEPs as two different legumain subfamilies.

plant biology↗

bioRxiv2021

Digital 3D Brain MRI Arterial Territories Atlas

The locus and extent of brain damage in the event of vascular insult can be quantitatively established quickly and easily with vascular atlases. Although highly anticipated by clinicians and clinical researchers, no digital MRI arterial atlas is readily available for automated data analyses. We created a digital arterial territory atlas based on lesion distributions in 1,298 patients with acute stroke. The lesions were manually traced in the diffusion-weighted MRIs, binary stroke masks were mapped to a common space, probability maps of lesions were generated and the boundaries for each arterial territory was defined based on the ratio between probabilistic maps. The atlas contains the definition of four major supra- and infra-tentorial arterial territories: Anterior, Middle, Posterior Cerebral Arteries and Vertebro-Basilar, and sub-territories (thalamoperforating, lenticulostriate, basilar and cerebellar arterial territories), in two hierarchical levels. This study provides the first publicly-available, digital, 3D deformable atlas of arterial brain territories, which may serve as a valuable resource for large-scale, reproducible processing and analysis of brain MRIs of patients with stroke and other conditions.

neuroscience↗

bioRxiv2017

Sympathetic Transmitters Controlling Thermogenic Efficacy of Brown Adipocytes by Modulating Mitochondrial Complex V

Obesity is epidemic worldwide as the results of excessive energy intake or inefficient energy expenditure. It is promising to utilize the thermogenic function of brown adipose tissue for obesity intervention. However, the mechanisms controlling the efficacy of norepinephrine-induced thermogenesis in brown adipocytes remain elusive. Here, we demonstrate that the proton ATPase activity of mitochondrial complex V is a key factor, which antagonizes proton leak by UCP1 and determines the efficacy of norepinephrine-induced thermogenesis in brown adipocytes. Furthermore, to avoid unnecessary and undesired heat production, we reveal that ATP as a sympathetic cotransmitter is necessary for the high efficacy and specificity of norepinephrine-induced thermogenesis in brown adipocytes by upregulating the ATP synthase activity of complex V. Thus, we demonstrate the modulation mechanism of thermogenic efficacy in brown adipocytes. These findings imply new strategies for efficiently utilizing brown adipocytes thermogenic capacity, and therapeutic targets for the treatments of obesity and diabetes.\n\nHighlights1. Norepinephrine (NE) induces heterogeneous responses in brown adipocytes\n\n2. NE activates the H+-ATPase activity of mitochondrial complex V\n\n3. Mitochondrial complex V is a key factor in NE-induced thermogenic efficacy\n\n4. ATP as a sympathetic cotransmitter enhances the NE-induced thermogenic efficacy

cell biology↗