Visible light-driven photocatalytic sulfonative oxidation of benzyl secondary amines.

A method for the α-oxidation and sulfonation of benzyl secondary amines was developed utilizing Ir(III) or Eosin Y as the photocatalyst in the presence of O2 as a green oxidant. Using commercial substrates, 37 products from cyclic and acyclic benzylamines were achieved with good functional group compatibility in 48-87% yields. Furthermore, tetrahydroisoquinoline protected by an Ac or a Boc group was oxidized under standard conditions.

Effect of phenyllactic acid on silage fermentation and bacterial community of reed canary grass on the Qinghai Tibetan Plateau.

BACKGROUND: This study aimed to investigate the effect of phenyllactic acid as an additive on silage fermentation and bacterial community of reed canary grass (RCG, Phalaris arundinacea L.) on the Qinghai Tibetan Plateau. At the heading stage, RCG was harvested, chopped and ensiled in small bag silos. The silage was treated without (control, 1.0 g/mL sterile water, on a fresh matter basis (FM)) or with phenyllactic acid (PLA, 3 mg/mL, FM), antimicrobial additive (PSB, a mixture of potassium sorbate and sodium benzoate, 2%, FM), lactic acid bacteria inoculant (LABi, L. plantarum + L. curvatus, 1 × 106 cfu/g, FM) and PLA + LABi, and then stored in a dark room at the ambient temperature (5 ~ 15 °C) for 60 days. RESULTS: Compared with control, PLA decreased lactic acid, acetic acid and ammonia-N contents, and subsequently increased CP content of RCG silage. PLA enhanced the growth of lactic acid bacteria and reduced the count of yeasts (P < 0.05) in RCG silage, with reduced bacterial richness index (Chao1), observed operational taxonomic units and diversity index (Simpson). In relative to control, moreover, PLA and PLA + LABi increased the relative abundance of Lactococcus in RCG silage by 27.73 and 16.93%, respectively. CONCLUSIONS: Therefore, phenyllactic acid at ensiling improved nutritional quality of RCG silage by advancing the disappearance of yeasts and the dominance of Lactococcus.

Effects of N Fertilization During Cultivation and Lactobacillus plantarum Inoculation at Ensiling on Chemical Composition and Bacterial Community of Mulberry Silage.

As unconventional forage source, mulberry (Morus alba L.) has been cultivated to alleviate animal feed shortages. This study aimed to investigate the effects of N fertilization during cultivation and Lactobacillus plantarum inoculation at ensiling on the chemical composition and bacterial community of mulberry silage. Mulberry was separately cultivated under two N fertilization rates (N1, 390 kg/ha/year; N2, 485 kg/ha/year) in 2016-2019, harvested on 30 April (the first-cut) and 15 June (the second-cut) in 2019, and then chopped for producing small bag silage. The silage was treated without (control) or with L. plantarum (LP, a recommended application rate of 105 cfu/g on fresh matter basis). After storage of 60 days in dark room at ambient temperature, silage was sampled for analysis of chemical and microbial compositions. Higher (P < 0.05) final pH value and acetic acid content and lower (P < 0.05) lactic acid content were found in silage of mulberry under N2 fertilization, resulting in more dry matter loss than that under N1 fertilization. Compared with control, inoculation of LP at ensiling increased (P < 0.05) lactic acid content and decreased (P < 0.05) final pH value, acetic acid and propionic acid contents of silage, by advancing the dominance of Lactobacillus and reducing the abundance of Enterococcus and Enterobacter. In particular, inoculation of LP at ensiling decreased (P < 0.05) dry matter loss and butyric acid content of first-cut silage. In conclusion, inoculation of LP at ensiling could reduce the undesirable effects from high N fertilization rate during cultivation on silage quality of mulberry harvested at different growing seasons.

Effects of Delayed Harvest and Additives on Fermentation Quality and Bacterial Community of Corn Stalk Silage.

This study aimed to investigate the effects of delayed harvest and additives on the fermentation quality and bacterial community of corn stalk silage in South China. The corn stalks after ear harvest at the 0 day (D0), 7 days (D7), and 15 days (D15) were used to produce small-bale silages. The silages at each harvest time were treated without (control, CK) or with Lactobacillus plantarum (LP) and sodium benzoate (BF). The results showed that delayed harvest increased pH and acetic acid content and reduced lactic acid content in corn stalk silage (p < 0.05). Compared with CK, the additives decreased the contents of butyric acid and ammonia nitrogen (NH3-N; p < 0.05). The silage treated with LP increased the content of lactic acid and decreased pH (p < 0.05); the silage treated with BF decreased counts of coliform bacteria and yeasts and increased residual water soluble carbohydrates (WSC) content (p < 0.05). Single Molecule, Real-Time sequencing (SMRT) revealed that the abundance of L. plantarum increased, while the abundance of Lactobacillus brevis and Lactobacillus ginsenosidimutans decreased with the delayed harvest. Additives influenced the bacterial community structure of corn stalk silage, revealed by enhanced bacterial diversity on D0 and reduced on D7 (p < 0.05). Our research indicated that delayed harvest could exert a positive effect on acetic acid production, and additives could inhibit the butyric acid fermentation and protein degradation of corn stalk silage by shifting bacterial community composition.

Effects of Phenyllactic Acid, Lactic Acid Bacteria, and Their Mixture on Fermentation Characteristics and Microbial Community Composition of Timothy Silage.

This study investigated the effects of phenyllactic acid (PL), lactic acid bacteria (LAB), and their mixture on fermentation characteristics and microbial community composition of timothy silage. Timothy silages were treated without (CK) or with PL [10 mg/kg fresh matter (FM) basis], LAB inoculant (IN; a mixture of Lactobacillus plantarum and L.buchneri, 105 cfu/g FM), and their mixture (PI) and stored at ambient temperature (5°C∼15°C) in a dark room for 60 days. Compared with CK, all treated silages showed lower (P < 0.05) levels of butyric acid and ammonia-N. Treatment with PL enhanced (P < 0.05) the crude protein preservation of silage by favoring the growth of L. curvatus and Saccharomyces cerevisiae and inhibition of lactic acid-assimilating yeast belonging to Issatchenkia during ensiling. In particular, treatment with PL advanced (P < 0.05) the productions of lactic acid and volatile fatty acid in IN-treated silage. Therefore, PL used as a new additive exhibited potential for improving silage fermentation when it is combined with LAB IN during ensiling.

LncRNA KLF3-AS1 in human mesenchymal stem cell-derived exosomes ameliorates pyroptosis of cardiomyocytes and myocardial infarction through miR-138-5p/Sirt1 axis.

AIM: Myocardial infarction (MI) is a severe disease with increased mortality and disability rates, posing heavy economic burden for society. Exosomes were uncovered to mediate intercellular communication after MI. This study aims to explore the effect and mechanism of lncRNA KLF3-AS1 in exosomes secreted by human mesenchymal stem cells (hMSCs) on pyroptosis of cardiomyocytes and MI. METHODS: Exosomes from hMSCs were isolated and identified. Exosomes from hMSCs with transfection of KLF3-AS1 for overexpression were injected into MI rat model or incubated with hypoxia cardiomyocytes. Effect of KLF3-AS1 on MI area, cell viability, apoptosis, and pyroptosis was determined. The relationship among miR-138-5p, KLF3-AS1, and Sirt1 was verified by dual-luciferase reporter assay. Normal cardiomyocytes were transfected with miR-138-5p inhibitor or sh-Sirt1 to clarify whether alteration of miR-138-5p or sh-Sirt1 can regulate the effect of KLF3-AS1 on cardiomyocytes. RESULTS: Exosomes from hMSCs were successfully extracted. Transfection of KLF3-AS1 exosome in rats and incubation with KLF3-AS1 exosome in hypoxia cardiomyocytes both verified that overexpression of KLF3-AS1 in exosomes leads to reduced MI area, decreased cell apoptosis and pyroptosis, and attenuated MI progression. KLF3-AS1 can sponge miR-138-5p to regulate Sirt1 expression. miR-138-5p inhibitor transfection and KLF3-AS1 exosome incubation contribute to attenuated pyroptosis and MI both in vivo and in vitro, while transfection of sh-Sirt1 could reverse the protective effect of exosomal KLF3-AS1 on hypoxia cardiomyocytes. CONCLUSION: LncRNA KLF3-AS1 in exosomes secreted from hMSCs by acting as a ceRNA to sponge miR-138-5p can regulate Sirt1 so as to inhibit cell pyroptosis and attenuate MI progression.

Aloperine Activates the PI3K/Akt Pathway and Protects Against Coronary Microembolisation-Induced Myocardial Injury in Rats.

BACKGROUND: Coronary microembolisation (CME)-induced myocardial apoptosis is a key factor in progressive cardiac dysfunction. Aloperine (ALO) plays a protective role in the cardiovascular system, but its role and the mechanism -underlying its protection against CME are unclear. Therefore, we aimed to verify whether ALO has a protective effect against CME-induced myocardial injury, as well as whether this effect has a relationship with regulation of the PI3K/Akt pathway for rats. METHODS: Forty Sprague-Dawley rats were randomised into 4 equal groups: CME, CME + ALO, CME + ALO + LY294002 (LY) and a Sham group. Twelve hours after surgery, the rats' cardiac function, apoptosis index, microinfarct and serum cardiac-troponin I (cTnI) level were measured. Levels of p-Akt, total Akt, Bcl-2, Bax and cleaved caspase-3 were detected. RESULTS: ALO improved cardiac dysfunction induced by CME, while also decreasing serum levels of cTnI and microinfarct areas. In addition, ALO inhibited myocardial apoptosis, which may have been partially as a result of downregulated cleaved caspase-3 and Bax, upregulated Bcl-2 and increased protein levels in phosphorylated Akt. However, these ALO effects were blocked if ALO was administered along with LY. CONCLUSIONS: ALO can inhibit cardiomyocyte apoptosis and consequently attenuate CME-induced myocardial injury. These functions are realised by activating PI3K/Akt signalling pathway.

Resveratrol Attenuates Cardiomyocyte Apoptosis in Rats Induced by Coronary Microembolization Through SIRT1-Mediated Deacetylation of p53.

OBJECTIVE: Coronary microembolization (CME)-induced cardiomyocyte apoptosis is the primary factor in causing cardiac dysfunction. Resveratrol (RES) is known to play a protective role in a variety of cardiovascular diseases, yet it is not known whether RES has a protective role in CME. Therefore, the effect of RES on cardiomyocyte apoptosis and cardiac function damage which are induced by CME in rats was investigated in this study. METHODS: Fifty Sprague-Dawley rats were separated into 5 groups randomly (10 rats were included in each): sham group, CME group, RES+CME group, RES+CME+Sirtuin-1 (SIRT-1) inhibitor EX527 (RES+CME+EX) group, and CME+EX group. Cardiac function, serum c-troponin I (cTnI) level, apoptotic index, and microinfarct were measured by cardiac ultrasound, myocardial enzyme assessment, TdT-mediated dUTP Nick-end labeling and hematoxylin-basic fuchsin-picric acid staining. The levels of p53, p53 acetylation, SIRT-1, Bax, Bcl-2, and cleaved caspase-3 were detected by Western blot. RESULTS: Myocardial dysfunction, enhanced apoptotic index as well as cTnI were caused after the operation of CME. Coronary microembolization induced increased expression of p53 acetylation and cleaved caspase-3, while the SIRT-1 and Bcl-2/Bax ratio was reduced. The CME effect was reversed by RES while EX527 attenuated this protective effect. CONCLUSIONS: Resveratrol can improve cardiac function, in the sense that it attenuates CME-induced cardiomyocyte apoptosis, which is perhaps associated with its inhibition pro-apoptotic pathway of p53 which is transcription-independent.

Nobiletin protects against myocardial injury and myocardial apoptosis following coronary microembolization via activating PI3K/Akt pathway in rats.

It has been found that use of drugs which upregulate the PI3K/Akt pathway can effectively reduce cardiomyocyte apoptosis which has been induced by coronary microembolization (CME). However, whether this functional protein is able to be modified through pretreatment via nobiletin (NOB) in models of CME has not yet been investigated. Therefore, this study set out to explore the cardioprotective effect of NOB on rats with myocardial injuries induced by CME and also explored the potential mechanism which underlies this cardioprotective effect. The study used 40 Sprague-Dawley (SD) rats, which were randomized into four groups: the sham, CME, CME+NOB, and CME+NOB+LY294002 (LY) groups. Twelve hours after surgery, levels of microinfarct, serum c-troponin I (cTnI), cardiac function, apoptotic index, and oxidative stress [superoxide dismutase (SOD) and malondialdehyde (MDA)] were measured for rats in each group. Western blot analysis was performed to detect any protein involved in the PI3K/Akt pathway. Nobiletin improved cardiac dysfunction which had been induced by CME, decreased serum level of cTnI and MDA, and increased serum SOD activities. In addition, nobiletin inhibited myocardial apoptosis, which may be connected to downregulated apoptotic index, upregulated Bcl-2, and cleaved caspase-3 and Bax, while it increased protein levels in phosphorylated Akt. However, when nobiletin was co-administered with LY294002, a PI3K (phosphatidylinositol 3-kinase)/Akt inhibitor, all of the previously mentioned effects were blocked. Nobiletin is able to inhibit cardiomyocyte apoptosis and can consequently attenuate CME-induced myocardial injuries. These functions are realized through the activation of the PI3K/Akt signaling pathway as well as by reducing oxidative stress.

ILK promotes survival and self-renewal of hypoxic MSCs via the activation of lncTCF7-Wnt pathway induced by IL-6/STAT3 signaling.

Mesenchymal stem cells (MSCs) have been applied in treating various diseases including myocardial infarction (MI) and achieved a bit of success; however, the decreased survival rate of MSCs after transplantation greatly limited the efficacy for cell therapy. How to improve the MSC survival rate in stem cell transplantation has undoubtedly become urgent and genetic engineering may be an ideal and feasible way. In this study, we explored the effects on MSCs survival and self-renewal by overexpression of integrin-linked kinase (ILK) in MSCs under hypoxic stimulation and aimed to reveal the molecular mechanisms from the point of paracrine function of MSCs. We first found that overexpression of ILK induced the expression and secretion of IL-6 increased significantly in MSCs under hypoxic stimulation, and the survival and self-renewal of MSCs exposed to hypoxia were enhanced after ILK overexpression. Then the activation of JAK2/STAT3 signaling was detected because of the increased IL-6, and an lncRNA, named lncTCF7, was upregulated remarkably, promoting the activation of Wnt pathway that was required for keeping cell viability and stemness of MSCs. Moreover, we further verified that inhibition of STAT3 signaling by WP1066 and silencing lncTCF7 expression eliminated the protective effects of ILK overexpression on cell survival and self-renewal of MSCs under hypoxic sitmulation. In conclusion, our results uncovered a novel function of ILK to promote MSC survival and self-renewal, suggesting more application potentials of MSC cell therapy on MI.