From Medical Herb to Functional Food: Development of a Fermented Milk Containing Silybin and Protein from Milk Thistle.

Milk thistle is a traditional medicinal herb. Silybin is a medicinal component found in the seed coat of milk thistle, which has liver-protective and anti-cancer properties. Conventional studies have focused on the extraction of silybin with organic reagents, which was inapplicable to the food industry. This study aims to develop a fermented milk containing silybin and protein from the milk thistle seeds. A three step procedure was developed, comprising homogenization of milk thistle seeds, NaHCO3 heat treatment, and microbial fermentation. The silybin was characterized by high performance liquid chromatography, and the protein was quantified and electrophorized. It was found that the homogenization step was essential for the preparation of protein, and the NaHCO3 heat treatment was the crucial step in obtaining silybin. The optimal NaHCO3 treatment settings were 1% NaHCO3, 60°C, and 3 h, and the optimal strains for microbial fermentation were L131 (Rummeliibacillus stabekisii) and RS72 (Lactobacillus plantarum). The silybin yield in the fermented milk reached 11.24-12.14 mg/g seeds, accounting for 72.6-78.4% of the total silybin in the milk thistle seeds, and the protein yield reached 121.8-129.6 mg/g seeds. The fermented milk had a slightly sweet yoghurt-like flavor and could be used as a dietary supplement for silybin and protein.

Gold(I) selenium N-heterocyclic carbene complexes as potent antibacterial agents against multidrug-resistant gram-negative bacteria via inhibiting thioredoxin reductase.

Multidrug-resistant (MDR) Gram-negative bacteria have become a global threat to human life and health, and novel antibiotics are urgently needed. The thioredoxin (Trx) system can be used as an antibacterial target to combat MDR bacteria. Here, we found that two active gold(I) selenium N-heterocyclic carbene complexes H7 and H8 show more promising antibacterial effects against MDR bacteria than auranofin. Both H7 and H8 irreversibly inhibit the bacterial TrxR activity via targeting the redox-active motif, abolishing the capacity of TrxR to quench reactive oxygen species (ROS) and finally leading to oxidative stress. The increased cellular superoxide radical levels impact a variety of functions necessary for bacterial survival, such as cellular redox balance, cell membrane integrity, amino acid metabolism, and lipid peroxidation. In vivo data present much better antibacterial activity of H7 and H8 than auranofin, promoting the wound healing and prolonging the survival time of Carbapenem-resistant Acinetobacter baumannii (CRAB) induced peritonitis. Most notably in this study, we revealed the influence of gold(I) complexes on both the Trx system and the cellular metabolic states to better understand their killing mechanism and to support further antibacterial drug design.

Selenite Ameliorates Cadmium-induced Cytotoxicity Through Downregulation of ROS Levels and Upregulation of Selenoprotein Thioredoxin Reductase 1 in SH-SY5Y Cells.

Cadmium (Cd) as a ubiquitous toxic heavy metal in the environment, causes severe hazards to human health, such as cellular stress and organ injury. Selenium (Se) was reported to reduce Cd toxicity and the mechanisms have been intensively studied so far. However, it is not yet crystal clear whether the protective effect of Se against Cd-induced cytotoxicity is related to selenoproteins in nerve cells or not. In this study, we found that Cd inhibited selenoprotein thioredoxin reductase 1 (TrxR1; TXNRD1) and decreased the expression level of TrxR1, resulting in cellular oxidative stress, and Se supplements ameliorated Cd-induced cytotoxicity in SH-SY5Y cells. Mechanistically, the detoxification of Se against Cd is attributed to the increase of the cellular TrxR activity and upregulated TrxR1 protein level, culminating in strengthened antioxidant capacity. Results showed that Se supplements attenuated the ROS production and apoptosis in SH-SY5Y cells, and significantly mitigated Cd-induced SH-SY5Y cell death. This study may be a valuable reference for shedding light on the mechanism of Cd-induced cytotoxicity and the role of TrxR1 in Se-mitigated cytotoxicity of Cd in neuroblast cells, which may be helpful for understanding the therapeutic potential of Cd and Se in treating or preventing neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD).

Targeted Pyroptosis Is a Potential Therapeutic Strategy for Cancer.

As a type of regulated cell death (RCD) mode, pyroptosis plays an important role in several kinds of cancers. Pyroptosis is induced by different stimuli, whose pathways are divided into the canonical pathway and the noncanonical pathway depending on the formation of the inflammasomes. The canonical pathway is triggered by the assembly of inflammasomes, and the activation of caspase-1 and then the cleavage of effector protein gasdermin D (GSDMD) are promoted. While in the noncanonical pathway, the caspase-4/5/11 (caspase 4/5 in humans and caspase 11 in mice) directly cleave GSDMD without the assembly of inflammasomes. Pyroptosis is involved in various cancers, such as lung cancer, gastric cancer, hepatic carcinoma, breast cancer, and colorectal carcinoma. Pyroptosis in gastric cancer, hepatic carcinoma, breast cancer, and colorectal carcinoma is related to the canonical pathway, while both the canonical and noncanonical pathway participate in lung cancer. Moreover, simvastatin, metformin, and curcumin have effect on these cancers and simultaneously promote the pyroptosis of cancer cells. Accordingly, pyroptosis may be an important therapeutic target for cancer.

Isoforskolin and forskolin attenuate lipopolysaccharide-induced inflammation through TLR4/MyD88/NF-κB cascades in human mononuclear leukocytes.

The principal active component of isoforskolin (ISOF) is from the plant Coleus forskohlii, native to China, which has attracted much attention for its biological effects. We hypothesize that ISOF and forskolin (FSK) pretreatment attenuates inflammation induced by lipopolysaccharide (LPS) related to toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B (NF-κB) signaling. Mononuclear leukocytes (MLs) from healthy donors' blood samples were separated by using density gradient centrifugation. Protein levels of TLR4, MyD88, and NF-κB were detected using western blot and inflammatory cytokines interleukin (IL) 1ß, IL-2, IL-6, IL-21, IL-23, tumor necrosis factor (TNF) α, and TNF-ß were tested by enzyme-linked immunosorbent assay and Quantibody array in MLs. Our results showed that LPS augmented the protein levels of TLR4, MyD88, and NF-κB in MLs and the production of IL-1ß, IL-2, IL-6, IL-21, IL-23, TNF-α, and TNF-ß in supernatants of MLs. Despite treatment with ISOF and FSK prior to LPS, the protein levels of TLR4, MyD88, NF-κB, IL-1ß, IL-2, IL-6, IL-21, IL-23, TNF-α, and TNF-ß in MLs were apparently decreased. roflumilast (RF) and dexamethasone (DM) had a similar effect on MLs with ISOF and FSK. Our results, for the first time, have shown that ISOF and FSK attenuate inflammation in MLs induced by LPS through down-regulating protein levels of IL-1ß and TNF-α, in which TLR4/MyD88/NF-κB signal pathway could be involved.