Xinmaikang-mediated mitophagy attenuates atherosclerosis via the PINK1/Parkin signaling pathway.

BACKGROUND: The Chinese herbal compound Xinmaikang (XMK) is effective in treating atherosclerosis (AS), although the associated mechanisms of action remain unclear. We hypothesize that XMK increases mitophagy via the PINK1/Parkin signaling pathway and decreases reactive oxygen species (ROS), thus treating AS. PURPOSE: To explore the above-mentioned mechanisms of action of XMK in AS. MATERIALS AND METHODS: Ultra-performance liquid chromatography assay was performed to clarify the composition of XMK. A 16-week high-fat diet was fed to APOE-/- mice to form an AS model. Next, mice were given XMK(0.95 g/kg/d, 1.99 g/kg/d, 3.98 g/kg/d, i.g.) or Atorvastatin(3 mg/kg/d, i.g.) or Rapamycin(4 mg/kg/d, i.p.) or XMK with Mdivi-1(40 mg/kg/d, i.p.) or an equivalent amount of normal saline for 4 weeks. Then mice were examined for AS plaque area, lesion area, collagen fiber, pro-inflammatory cytokines, lipid level, ROS level and mitophagy level. We assessed AS using Oil Red O, hematoxylin and eosin, and Sirius red staining, as well as ROS measurements. Mitophagy was evaluated by transmission electron microscopy, real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, single-cell Western blot, and immunofluorescence staining. In vitro, by oxidizing low-density lipoprotein, formation of RAW264.7 macrophage-derived foam cells induced. we induced foam cell formation in RAW264.7 macrophages. Then cells were incubated with XMK-medicated serum with or without Mdivi-1. We examined foam cell formation, ROS level, mitophagy level in cells. Finally, we knocked down the PINK1, and examined foam cell formation and PINK1/Parkin level in RAW264.7 macrophages. RESULTS: UPLC analysis revealed 102 main ingredients in XMK. In vivo, XMK at medium-dose or high-dose significantly reduced AS plaques, lipids, pro-inflammatory cytokines, and ROS and increased mitophagy. In further study, Single-cell western blot showed that mitophagy level in macrophages sorted from AS mice was lower than the control mice. While XMK improved mitophagy level. In vitro, XMK reduced foam cell formation and ROS and increased mitophagy. When PINK1 was knocked down, XMK's effects on foam cell formation and PINK1/Parkin pathway activation were reduced. CONCLUSION: The study shows that XMK is effective against AS by mediating macrophage mitophagy via the PINK1/Parkin signaling pathway. For the treatment of AS and drug discovery, it provides an experimental basis and target.

Selenium Content and/or T-2 Toxin Contamination of Cereals, Soil, and Children's Hair in Some Areas of Heilongjiang and Gansu Provinces, China.

It has been strongly suggested that selenium deficiency and T-2 contamination in cereals are responsible for the development of Kashin-Beck disease (KBD). In order to assess these risk factors of KBD in the internal and external environments, our team undertook a two-stage survey in some areas of Heilongjiang and Gansu Provinces, China. The selenium content in children's hair (293), cereal (192), and soil (46) samples were determined using the 2, 3-diamino-naphthalene fluorometric assay technique. The T-2 toxin contamination level in the cereal samples (704) was assayed using an ELISA kit. There were no clinical KBD cases identified in this survey. The selenium statuses of the children in all the investigated regions during the first phase were at the medium selenium nutrition level. During the second phase, the selenium status of the children in Weiyuan County, Ning County, and Shangzhi City was at the medium selenium nutrition level, at the edge of selenium deficiency, and selenium deficient, respectively. Furthermore, the selenium contents in the cereal and soil samples were low. During the first phase, the average T-2 toxin contamination level in the family staple food samples for all the investigated regions was about 10 ng/g. However, the T-2 toxin contamination levels in eight homegrown corn samples were higher than 100 ng/g. During the second phase, all the average T-2 toxin contamination levels in the flour and corn samples from the three investigated regions were less than 10 ng/g. Risk factors that affect the prevalence of KBD still remain in the internal and external environments of some areas in Heilongjiang and Gansu Provinces.

Specificity protein 1 regulates gene expression related to fatty acid metabolism in goat mammary epithelial cells.

Specificity protein 1 (SP1) is a ubiquitous transcription factor that plays an important role in controlling gene expression. Although important in mediating the function of various hormones, the role of SP1 in regulating milk fat formation remains unknown. To investigate the sequence and expression information, as well as its role in modulating lipid metabolism, we cloned SP1 gene from mammary gland of Xinong Saanen dairy goat. The full-length cDNA of the SP1 gene is 4376 bp including 103 bp of 5'UTR, 2358 bp of ORF (HM_236311) and 1915 bp of 3'UTR, which is predicted to encode a 786 amino acids polypeptide. Phylogenetic tree analysis showed that goat SP1 has the closest relationship with sheep, followed by bovines (bos taurus, odobenus and ceratotherium), pig, primates (pongo, gorilla, macaca and papio) and murine (rattus and mus), while the furthest relationship was with canis and otolemur. Expression was predominant in the lungs, small intestine, muscle, spleen, mammary gland and subcutaneous fat. There were no significant expression level differences between the mammary gland tissues collected at lactation and dry-off period. Overexpression of SP1 in goat mammary epithelial cells (GMECs) led to higher mRNA expression level of peroxisome proliferator-activated receptor-γ (PPARγ) and lower liver X receptor α (LXRα) mRNA level, both of which were crucial in regulating fatty acid metabolism, and correspondingly altered the expression of their downstream genes in GMECs. These results were further enhanced by the silencing of SP1. These findings suggest that SP1 may play an important role in fatty acid metabolism.