[Effect of processing method on chemical constituents of Rehmanniae Radix: based on UHPLC-LTQ-Orbitrap MS].

This study aims to explore the chemical composition of Rehmanniae Radix braised with mild fire and compare the effect of processing method on the chemical composition of Rehmanniae Radix. To be specific, ultra-high performance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) was used to screen the chemical constituents of Rehmanniae Radix. The chemical constituents were identified based on the relative molecular weight and fragment ions, literature information, and Human Metabolome Database(HMDB). The ion peak area ratio of each component before and after processing was used as the index for the variation. SIMCA was employed to establish principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) models of different processed products. According to the PCA plot, OPLS-DA plot, and VIP value, the differential components before and after the processing were screened out. The changes of the content of differential components with the processing method were analyzed. A total of 66 chemical components were identified: 57 of raw Rehmanniae Radix, 55 of steamed Rehmanniae Radix, 55 of wine-stewed Rehmanniae Radix, 51 of repeatedly steamed and sundried Rehmanniae Radix Praeparata, 62 of traditional bran-braised Rehmanniae Radix, and 63 of electric pot-braised Rehmanniae Radix. Among them, the 9 flavonoids of braised Rehmanniae Radix were from Citri Reticulatae Pericarpium. PCA suggested significant differences in the chemical composition of Rehmanniae Radix Praeparata prepared with different processing methods. OPLS-DA screened out 32 chemical components with VIP value >1 as the main differential components. Among the differential components, 9 were unique to braised Rehmanniae Radix(traditional bran-braised, electric pot-braised) and the degradation rate of the rest in braised(traditional bran-braised, electric pot-braised) or repeatedly steamed and sundried Rehmanniae Radix was higher than that in the steamed or wine-stewed products. The results indicated the chemical species and component content of Rehmanniae Radix changed significantly after the processing. The 32 components, such as rehmapicrogenin, martynoside, jionoside D, aeginetic acid, hesperidin, and naringin, were the most important compounds to distinguish different processed products of Rehmanniae Radix. The flavonoids introduced by Citri Reticulatae Pericarpium as excipient may be the important material basis for the effectiveness of braised Rehmanniae Radix compared with other processed products.

Anti-diabetic drug canagliflozin hinders skeletal muscle regeneration in mice.

Canagliflozin is an antidiabetic medicine that inhibits sodium-glucose cotransporter 2 (SGLT2) in proximal tubules. Recently, it was reported to have several noncanonical effects other than SGLT2 inhibiting. However, the effects of canagliflozin on skeletal muscle regeneration remain largely unexplored. Thus, in vivo muscle contractile properties recovery in mice ischemic lower limbs following gliflozins treatment was evaluated. The C2C12 myoblast differentiation after gliflozins treatment was also assessed in vitro. As a result, both in vivo and in vitro data indicate that canagliflozin impairs intrinsic myogenic regeneration, thus hindering ischemic limb muscle contractile properties, fatigue resistance recovery, and tissue regeneration. Mitochondrial structure and activity are both disrupted by canagliflozin in myoblasts. Single-cell RNA sequencing of ischemic tibialis anterior reveals a decrease in leucyl-tRNA synthetase 2 (LARS2) in muscle stem cells attributable to canagliflozin. Further investigation explicates the noncanonical function of LARS2, which plays pivotal roles in regulating myoblast differentiation and muscle regeneration by affecting mitochondrial structure and activity. Enhanced expression of LARS2 restores the differentiation of canagliflozin-treated myoblasts, and accelerates ischemic skeletal muscle regeneration in canagliflozin-treated mice. Our data suggest that canagliflozin directly impairs ischemic skeletal muscle recovery in mice by downregulating LARS2 expression in muscle stem cells, and that LARS2 may be a promising therapeutic target for injured skeletal muscle regeneration.

Overexpression of MiR-633 Suppresses the Tumorigenicity of Gastric Cancer Cells and Induces Apoptosis by Targeting MAPK1.

OBJECTIVE: MicroRNA (miRNA/miR)-633 is dysregulated in several types of cancers and is involved in tumorigenesis. However, the function and role of this miRNA in gastric cancer (GC) are not fully understood. The aim of the present study was to evaluate miR-633 expression in GC cell lines and in GC tissue vs. adjacent normal tissue, and to determine its association with clinicopathological data. This work was extended to investigate the effects of miR-633 overexpression on tumor cells in vitro. METHODS: Reverse transcription-quantitative PCR (RT-qPCR) was used to detect and compare the expression level of miR-633 in GC cells, as well as in GC and normal adjacent tissue samples. The clinical significance of miR-633 was also analyzed. MiR-633 lentivirus (LV-miR-633) and negative control lentivirus (LV-NC) were generated and used to transduce SGC-7901 and HGC-27 GC cells in order to analyze the effect of miR-633 on their phenotype. The effects of miR-633 overexpression on GC cell proliferation, apoptosis, migration and invasion were investigated. The target gene of miR-633 was predicted, then confirmed using a dual luciferase reporter gene assay, RT-qPCR and Western blotting. RESULTS: MiR-633 was significantly downregulated in GC cell lines, as well as in GC tissue compared with adjacent normal tissue. Moreover, miR-633 expression was associated with the tumor/node/metastasis (TNM) stage, invasion depth, Borrmann classification and lymph node metastasis (P<0.05). Compared with the LV-NC group, transduction with LV-miR-633 reduced the proliferation, the number of clones, the wound healing rate, the number of invading cells and the number of cells in the G1 phase of the cell cycle (P<0.01). LV-miR-633 also increased the apoptosis rate (P<0.01). The expression level of mitogen-activated protein kinase (MAPK) 1, high-mobility group box 3 (HMGB3), claudin 1 (CLDN1) and MAPK13 were downregulated in LV-miR-633-transduced cells (P<0.01). The dual luciferase reporter assay confirmed that the 3'-untranslated region of MAPK1 was the target site of miR-633 (P<0.01). CONCLUSION: MiR-633 acts as a tumor suppressor in GC, and its expression level is associated with TNM stage, invasion depth, Borrmann type and lymph node metastasis. Overexpression of miR-633 inhibits the proliferation and migration of GC cells and induces apoptosis and cell cycle arrest at the in G1 phase. In addition, miR-633 negatively regulates the expression of MAPK1, HMGB3, CLDN1 and MAPK13 and directly targets MAPK1.