The Antivirulence Activity of Umbelliferone and Its Protective Effect against A. hydrophila-Infected Grass Carp

JunD functions as a transcription factor of IL-10 to regulate bacterial infectious inflammation in grass carp (Ctenopharyngodon idella)

IL-10 is a key anti-inflammatory mediator ensuring the protection of a host from excessive inflammation in response to pathogen infections, whose transcription or expression levels are tightly linked to the onset and progression of infectious diseases. An AP-1 family member called CiJunD was shown to be a transcription factor of IL-10 in grass carp (Ctenopharyngodon idella) in the current study. CiJunD protein harbored the conserved Jun and bZIP domains. Mutant experiments demonstrated that CiJunD bound to three specific sites on IL-10 promoter, i.e., 5'-ATTATTCATA-3', 5'-AGATGAGACATCT-3', and 5'-ATTATTCATC-3', mainly relying on the bZIP domain, and initiated IL-10 transcription. Expression data from the grass carp spleen infected by Aeromonas hydrophila and lipopolysaccharide (LPS) challenged spleen leukocytes indicated that the expressions of CiJunD and IL-10 were positively correlated, while the expression of pro-inflammatory cytokines, such as IL-1β, IL-6, IL-8, IFN-γ, and TNF-α, showed an overall downward trend when CiJunD and IL-10 peaked. The ability of CiJunD to down-regulate the production of pro-inflammatory cytokines and up-regulate the expression of IL-10, both with and without LPS stimulation, was confirmed by overexpression experiments. Meanwhile, the subcellular fractionation assay revealed that the nuclear translocation of CiJunD was significantly enhanced after the LPS challenge. Moreover, in vivo administration of grass carp with Oxamflatin, a potent agonist of JunD activity, could promote IL-10 but suppress the expression of pro-inflammatory cytokines. Intriguingly, tissue inflammation lesions and the survival rates of grass carp infected with A. hydrophila were also significantly improved by Oxamflatin administration. This work sheds light on the regulation mechanism by JunD of IL-10 expression and bacterial infectious inflammation for the first time, and it may present a viable method for preventing infectious diseases in fish by regulating IL-10 expression and inflammatory response.

Simple phenylpropanoids: recent advances in biological activities, biosynthetic pathways, and microbial production

Covering: 2000 to 2023Simple phenylpropanoids are a large group of natural products with primary C6-C3 skeletons. They are not only important biomolecules for plant growth but also crucial chemicals for high-value industries, including fragrances, nutraceuticals, biomaterials, and pharmaceuticals. However, with the growing global demand for simple phenylpropanoids, direct plant extraction or chemical synthesis often struggles to meet current needs in terms of yield, titre, cost, and environmental impact. Benefiting from the rapid development of metabolic engineering and synthetic biology, microbial production of natural products from inexpensive and renewable sources provides a feasible solution for sustainable supply. This review outlines the biological activities of simple phenylpropanoids, compares their biosynthetic pathways in different species (plants, bacteria, and fungi), and summarises key research on the microbial production of simple phenylpropanoids over the last decade, with a focus on engineering strategies that seem to hold most potential for further development. Moreover, constructive solutions to the current challenges and future perspectives for industrial production of phenylpropanoids are presented.

Taming Food-Drug Interaction Risk: Potential Inhibitory Effects of Citrus Juices on Cytochrome Liver Enzymes Can Safeguard the Liver from Overdose Paracetamol-Induced Hepatotoxicity

Paracetamol overdose is the leading cause of drug-induced hepatotoxicity worldwide. Because of N-acetyl cysteine's limited therapeutic efficacy and safety, searching for alternative therapeutic substitutes is necessary. This study investigated four citrus juices: Citrus sinensis L. Osbeck var. Pineapple (pineapple sweet orange), Citrus reticulata Blanco × Citrus sinensis L. Osbeck (Murcott mandarin), Citrus paradisi Macfadyen var. Ruby Red (red grapefruit), and Fortunella margarita Swingle (oval kumquat) to improve the herbal therapy against paracetamol-induced liver toxicity. UHPLC-QTOF-MS/MS profiling of the investigated samples resulted in the identification of about 40 metabolites belonging to different phytochemical classes. Phenolic compounds were the most abundant, with the total content ranked from 609.18 to 1093.26 μg gallic acid equivalent (GAE)/mL juice. The multivariate data analysis revealed that phloretin 3',5'-di-C-glucoside, narirutin, naringin, hesperidin, 2-O-rhamnosyl-swertisin, fortunellin (acacetin-7-O-neohesperidoside), sinensetin, nobiletin, and tangeretin represented the crucial discriminatory metabolites that segregated the analyzed samples. Nevertheless, the antioxidant activity of the samples was 1135.91-2913.92 μM Trolox eq/mL juice, 718.95-3749.47 μM Trolox eq/mL juice, and 2304.74-4390.32 μM Trolox eq/mL juice, as revealed from 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid, ferric-reducing antioxidant power, and oxygen radical absorbance capacity, respectively. The in vivo paracetamol-induced hepatotoxicity model in rats was established and assessed by measuring the levels of hepatic enzymes and antioxidant biomarkers. Interestingly, the concomitant administration of citrus juices with a toxic dose of paracetamol effectively recovered the liver injury, as confirmed by normal sections of hepatocytes. This action could be due to the interactions between the major identified metabolites (hesperidin, hesperetin, phloretin 3',5'-di-C-glucoside, fortunellin, poncirin, nobiletin, apigenin-6,8-digalactoside, 6',7'-dihydroxybergamottin, naringenin, and naringin) and cytochrome P450 isoforms (CYP3A4, CYP2E1, and CYP1A2), as revealed from the molecular docking study. The most promising compounds in the three docking processes were hesperidin, fortunellin, poncirin, and naringin. Finally, a desirable food-drug interaction was achieved in our research to overcome paracetamol overdose-induced hepatotoxicity.

Umbelliferon: a review of its pharmacology, toxicity and pharmacokinetics

Coumarin, a plant secondary metabolite, has various pharmacological activities, including antioxidant stress and anti-inflammatory effects. Umbelliferone, a common coumarin compound found in almost all higher plants, has been extensively studied for its pharmacological effects in different disease models and doses with complex action mechanisms. This review aims to summarize these studies and provide useful information to relevant scholars. The pharmacological studies demonstrate that umbelliferone has diverse effects such as anti-diabetes, anti-cancer, anti-infection, anti-rheumatoid arthritis, neuroprotection, and improvement of liver, kidney, and myocardial tissue damage. The action mechanisms of umbelliferone include inhibition of oxidative stress, inflammation, and apoptosis, improvement of insulin resistance, myocardial hypertrophy, and tissue fibrosis, in addition to regulation of blood glucose and lipid metabolism. Among the action mechanisms, the inhibition of oxidative stress and inflammation is the most critical. In short, these pharmacological studies disclose that umbelliferone is expected to treat many diseases, and more research should be conducted.

Ferroptosis: a new strategy for Chinese herbal medicine treatment of diabetic nephropathy

Diabetic nephropathy (DN) is a serious microvascular complication of diabetes. It has become a leading cause of death in patients with diabetes and end-stage renal disease. Ferroptosis is a newly discovered pattern of programmed cell death. Its main manifestation is the excessive accumulation of intracellular iron ion-dependent lipid peroxides. Recent studies have shown that ferroptosis is an important driving factor in the onset and development of DN. Ferroptosis is closely associated with renal intrinsic cell (including renal tubular epithelial cells, podocytes, and mesangial cells) damage in diabetes. Chinese herbal medicine is widely used in the treatment of DN, with a long history and definite curative effect. Accumulating evidence suggests that Chinese herbal medicine can modulate ferroptosis in renal intrinsic cells and show great potential for improving DN. In this review, we outline the key regulators and pathways of ferroptosis in DN and summarize the herbs, mainly monomers and extracts, that target the inhibition of ferroptosis.

Bioactive Chemical Constituents and Pharmacological Activities of Ponciri Fructus

Ponciri Fructus is a crude drug obtained from the dried immature fruits of Poncirus trifoliata (L). Raf. (Syn. Citrus trifoliata L.). This study aims to compile and analyze the ethnomedicinal uses, bioactive constituents, and pharmacological activities of Ponciri Fructus. Various online bibliographic databases namely, SciFinder, PubMed, Google Scholar, and Web of Science were used for collecting information on traditional uses, biological activities, and bioactive constituents. Concerning ethnomedicinal uses, Ponciri Fructus is extensively used in traditional Korean, Chinese, and Kampo medicines to mitigate allergic reactions, inflammation, edema, digestive complications, respiratory problems, spleen-related problems, liver complications, neuronal pain, hyperlipidemia, rheumatoid arthritis, cardiovascular problems, hernia, sinusitis, and insomnia. Several studies have shown that Ponciri Fructus is a major source of diverse classes of bioactive compounds namely flavonoids, terpenoids, coumarins, phytosterols, and alkaloids. Several in vivo and in vitro pharmacological activity evaluations such as antidiabetic, anti-obesity, anti-inflammatory, antiallergic, antimelanogenic, gastroprotective, anticancer, and neuroprotective effects have been conducted from Ponciri Fructus. However, scientific investigations focusing on bioassay-guided isolation and identification of specific bioactive constituents are limited. Therefore, an in-depth scientific investigation of Ponciri Fructus focusing on bioassay-guided isolation, mechanism based pharmacological studies, pharmacokinetic studies, and evaluation of possible toxicities is necessary in the future.