Screening of Potential Probiotic Lactobacillaceae and Their Improvement of Type 2 Diabetes Mellitus by Promoting PI3K/AKT Signaling Pathway in db/db Mice.

The study aimed to isolate Lactobacillaceae strains with in vitro hypoglycemic activity and probiotic properties and to determine their antidiabetic abilities in vivo. Lactiplantibacillus plantarum 22, L. plantarum 25, Limosilactobacillus fermentum 11, and L. fermentum 305 with high in vitro hypoglycemic activity were screened from 23 strains of Lactobacillaceae isolated from human feces and identified by 16S rDNA sequencing. The fasting blood glucose (FBG) of the mice was recorded weekly. After 12 weeks, liver, kidney, and pancreas tissues were stained with hematoxylin and eosin (H&E) to observe histomorphology; the inflammatory factors were assayed by Quantitative Real-time PCR; PI3K and AKT were measured by Western blot; the short-chain fatty acids (SCFAs) were determined by LC-MS/MS. Inhibitory activities of L. plantarum 22, L. plantarum 25, L. fermentum 11, and L. fermentum 305 against α-amylase were 62.29 ± 0.44%, 51.81 ± 3.65%, 58.40 ± 1.68%, and 57.48 ± 5.04%, respectively. Their inhibitory activities to α-glucosidase were 14.89 ± 0.38%, 15.32 ± 0.89%, 52.63 ± 3.07%, and 51.79 ± 1.13%, respectively. Their survival rate after simulated gastrointestinal test were 12.42 ± 2.84%, 9.10 ± 1.12%, 5.86 ± 0.52%, and 8.82 ± 2.50% and their adhesion rates to Caco-2 cell were 6.09 ± 0.39%, 6.37 ± 0.28%, 6.94 ± 0.27%, and 6.91 ± 0.11%, respectively. The orthogonal tests of bacterial powders of the four strains showed that the maximum inhibitory activities to α-amylase and α-glucosidase were 93.18 ± 1.19% and 75.33 ± 2.89%, respectively. The results showed that the mixture of Lactobacillaceae could lower FBG, reduce inflammation, and liver, kidney, and pancreas damage, promote PI3K/AKT signaling pathway, and increase the content of SCFAs. The combination of L. plantarum 22, L. plantarum 25, L. fermentum 11, and L. fermentum 305 can potentially improve type 2 diabetes mellitus (T2DM).

Puerarin activates adaptive autophagy and protects the myocardium against doxorubicin-induced cardiotoxicity via the 14-3-3γ/PKCε pathway.

Doxorubicin (Dox)-induced cardiotoxicity (DIC) seriously threatens the health of related patients. Studies have confirmed that 14-3-3γ and protein kinase C epsilon (PKCε) are the endogenous protective proteins. Puerarin (Pue) is a bioactive ingredient isolated from the root of Pueraria lobata. It possesses many pharmacological properties, which have been widely used in treating and adjuvant therapy of cardiovascular diseases. In the study, we intended to explore the effects and mechanism of Pue pretreatment to protect the myocardium against DIC injury. Adult mice and H9c2 cells were pretreated with Pue, and the injury model was made with Dox. Results showed that Pue pretreatment alleviated DIC injury, as revealed by increased cell viability, decreased LDH activity and apoptosis, inhibited excess oxidative stress, maintained mitochondrial function and energy metabolism, and improved myocardial function. Furthermore, Pue pretreatment upregulated 14-3-3γ expression, interacted with PKCε, phosphorylated and impelled migration to mitochondria, activated adaptive autophagy, and protected the myocardium. However, pAD/14-3-3γ-shRNA or εV1-2 (a PKCε activity inhibitor) or 3-methyladenine (an autophagy inhibitor) could weaken the above effects of Pue pretreatment. Together, Pue pretreatment could activate adaptive autophagy by the 14-3-3γ/PKCε pathway and protect the myocardium against DIC injury.

Puerarin attenuates lipopolysaccharide-induced myocardial injury via the 14-3-3γ/PKCε pathway activating adaptive autophagy.

Studies have confirmed that the heart is the main target organ of lipopolysaccharide (LPS) attacks, and 14-3-3γ and protein kinase C epsilon (PKCε) are the endogenous protective proteins. Puerarin (Pue) is the major bioactive ingredient isolated from the root of Pueraria lobata. It possesses many pharmacological properties, which has been widely used in the treatment and adjuvant therapy of cardio- and cerebrovascular diseases and cancer, etc. The study intended to explore the effects and mechanism of Pue pretreatment to protect myocardium against LPS injury. Adult mice and primary cultured neonatal rat cardiomyocytes were pretreated with Pue, and the injury model was made with LPS. Results showed that Pue pretreatment alleviated LPS-induced injury, as demonstrated by increased cell viability, decreased LDH activity and apoptosis, inhibited excess oxidative stress and the inflammatory cytokine release, and maintained mitochondrial function. Furthermore, Pue pretreatment upregulated 14-3-3γ expression, interacted with PKCε, which was phosphorylated and impelled migration to mitochondria, and then activated adaptive autophagy and protected the myocardium. However, pAD/14-3-3γ-shRNA or 3-MA (an autophagy inhibitor) could weaken the above effects of Pue pretreatment. Together, Pue pretreatment could activate adaptive autophagy by the 14-3-3γ/PKCε pathway and protect the myocardium against LPS injury.

α-Pyrones with glucose uptake-stimulatory activity from the twigs of Cryptocarya wrayi.

Five new α-pyrones, cryptowratones A-E (1-5), and five known congeners (6-10), together with four other known compounds 11-14 were isolated from the twigs of Cryptocarya wrayi. The structures of the new compounds were elucidated on the basis of extensive spectroscopic data analysis and ECD calculations. All α-pyrones except 6 were evaluated for their stimulatory effects on glucose uptake in vitro with CHO-K1/GLUT4 cells. The positive control insulin displayed an approximate 42 ± 0.14% promotion on glucose uptake at 25 µM, compared with the CHO-K1/GLUT4 group. Compounds 1a/2a, 2, 3, and 10 showed a more significant stimulation of glucose uptake than insulin (25 µM) by 36 ± 0.08%, 27 ± 0.12%, 28 ± 0.12%, and 25 ± 0.12% at 1.5 µM, respectively. Immunofluorescence assays indicated the glucose uptake-stimulatory activity of α-pyrones might be correlated with increased GLUT4 translocation.

The effects of quercetin protect cardiomyocytes from A/R injury is related to its capability to increasing expression and activity of PKCε protein.

Quercetin is a ubiquitous flavonoid found in vegetable foods. Epidemiological and animal studies have reported an inverse association between quercetin intakes and occurrence and development of various cardiovascular diseases. Some researchers have inferred that the mechanisms of quercetin to protect cardiomyocytes from ischemia/reperfusion injury may be involved in modulation of intracellular signal pathways and regulation of proteins expression beyond its antioxidant activity. The aim of this study was to investigate whether quercetin protect cardiomyocytes from anoxia/reoxygenation injury through PKCε pathway. Neonatal rat primary cardiomyocytes were pretreated with quercetin or quercetin plus εV1-2, a selective PKCε inhibitor, prior to A/R treatment. Western blotting analysis showed that the level of PKCε and phosphor-PKCε Ser297 in the quercetin pretreatment group were all increased significantly compared to the control or A/R group. Subsequent assays showed that pretreated with quercetin could increase the viability of neonatal rat primary cardiomyocytes suffered A/R, decrease the apoptosis and ROS and alleviate the loss of mitochondrial membrane potential induced by A/R injury. However, the protective effects of quercetin disappeared in the group pretreated with εV1-2. Thus, for the first time, we revealed that one of the mechanisms of quercetin protecting cardiomyocytes from A/R injury might be increase the expression of PKCε protein and then enhance the activity of its downstream pathway.