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Zhuang, H.

Publications and source records attributed to Zhuang, H..

4 recordsLinked to original sources

The effect of whey protein on viral infection and replication of SARS-CoV-2 and pangolin coronavirus in vitro

Since the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in human breastmilk, little is known about the antiviral property of human breastmilk to SARS-CoV-2 and its related pangolin coronavirus (GX_P2V). Here we present for the first time that whey protein from human breastmilk effectively inhibited both SARS-CoV-2 and GX_P2V by blocking viral attachment, entry and even post-entry viral replication. Moreover, human whey protein inhibited infectious virus production proved by the plaque assay. We found that whey protein from different species such as cow and goat also showed anti-coronavirus properties. And commercial bovine milk also showed similar activity. Interestingly, the main antimicrobial components of breastmilk, such as Lactoferrin and IgA antibody, showed limited anti-coronavirus activity, indicating that other factors of breastmilk may play the important anti-coronavirus role. Taken together, we reported that whey protein inhibits SARS-CoV-2 and its related virus of GX_P2V. These results rule out whey protein as a direct-acting inhibitor of SARS-CoV-2 and GX_P2V infection and replication and further investigation of its molecular mechanism of action in the context of COVID-19.

microbiology

Interactive effects of aging and aerobic capacity on energy metabolism-related metabolites of serum, skeletal muscle, and white adipose tissue

Aerobic capacity is a strong predictor of longevity. With aging, aerobic capacity decreases concomitantly with changes in whole body metabolism leading to increased disease risk. To address the role of aerobic capacity, aging and their interaction on metabolism, we utilized rat models of low and high intrinsic aerobic capacity (LCRs/HCRs) and assessed the metabolomics of serum, muscle, and white adipose tissue (WAT). We compared LCRs and HCRs at two time points: Young rats were sacrificed at 9 months, and old rats were sacrificed at 21 months. Targeted and semi-quantitative metabolomics analysis was performed on ultra-pressure Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS) platform. Interaction of aerobic capacity and aging was studied via regression analysis. Our results showed at young age, metabolites linked to amino acid metabolism differed in serum and muscle with aerobic capacity, whereas no difference were observed in WAT. In aged animals, most prominent changes in metabolites occurred in WAT. Aerobic capacity and aging interactively affected seven metabolites linked to energy metabolism. Our results support previous findings that high aerobic capacity is associated with more efficient amino acid metabolism in muscle. While impaired branched chain amino acids (BCAAs) and fatty acid metabolism in the muscle may associate to the high risk of metabolic disorders and shorter lifespan previously observed in LCRs. The interactive effects of aging and aerobic capacity on energy metabolism-related metabolites were largely driven by HCRs, reflecting the importance of inherited aerobic capacity in the aging process. Our results highlight that dysfunctional mitochondrial {beta}-oxidation in WAT may be one key mechanism related to aging.

molecular biology

SGT1 is not required for bacterial PAMP-triggered immunity

Plant immune signaling activated by the perception of pathogen-associated molecular patterns (PAMPs) or effector proteins is mediated by PRRs and NLRs, respectively, and often share cellular components and downstream responses. The suppressor of the G2 allele of skp1 (SGT1) is a core immune regulator required for the activation of NLR-mediated immunity. In this work, we examined the requirement of SGT1 for PRR-mediated immune responses in both Nicotiana benthamiana and Arabidopsis. Using complementary genetic approaches, we found that SGT1 is not limiting for early PRR-dependent responses or anti-bacterial immunity. Therefore, we conclude that SGT1 does not play a significant role in bacterial PAMP-triggered immunity.

plant biology

Intra-strain elicitation and suppression of plant immunity by Ralstonia solanacearum type-III effectors in Nicotiana benthamiana

Effector proteins delivered inside plant cells are powerful weapons for bacterial pathogens, but this exposes the pathogen to potential recognition by the plant immune system. Therefore, the effector repertoire of a given pathogen must be balanced for a successful infection. Ralstonia solanacearum is an aggressive pathogen with a large repertoire of secreted effectors. One of these effectors, RipE1, is conserved in most R. solanacearum strains sequenced to date. In this work, we found that RipE1 triggers immunity in N. benthamiana, which requires the immune regulator SGT1, but not EDS1 or NRCs. Interestingly, RipE1-triggered immunity induces the accumulation of salicylic acid (SA) and the overexpression of several genes encoding phenylalanine-ammonia lyases (PALs), suggesting that the unconventional PAL-mediated pathway is responsible for the observed SA biosynthesis. Surprisingly, RipE1 recognition also induces the expression of jasmonic acid (JA)-responsive genes and JA biosynthesis, suggesting that both SA and JA may act cooperatively in response to RipE1. Finally, we found that RipE1 expression leads to the accumulation of glutathione in plant cells, which precedes the activation of immune responses. R. solanacearum encodes another effector, RipAY, which is known to inhibit immune responses by degrading cellular glutathione. Accordingly, we show that RipAY inhibits RipE1-triggered immune responses. This work shows a strategy employed by R. solanacearum to counteract the perception of its effector proteins by the plant immune system.

plant biology