Improvement of lipid profile and hepatic oxidative stress in high-fat-diet induced hyperlipidemic Swiss albino rats by Piper betle juice: evidences from in vivo and in silico studies.

Piper betle L. leaves are very popular and traditionally used to chew with betel nut in many Asian countries. In this study, P. betle leaves juice (PBJ) was subjected to evaluation for its antihyperlipidemic activity in the high-fat-diet-induced hyperlipidemic rats model. Swiss albino rats were allowed to high-fat- diet for one month, followed by concurrent administration of PBJ for another month. The rats were then sacrificed and collected blood, tissues and organs. Pharmacokinetic, toxicological studies and molecular docking studies were performed using SwissADME, admetSAR and schrodinger suit-2017. Our investigation showed a promising effect of PBJ on body weight, lipid profile, oxidative and antioxidative enzymes, and the principle enzyme responsible for the synthesis of cholesterol. PBJ at 0.5 - 3.0 mL/rat significantly reduced body weight of hyperlipidemic rats compared to control. PBJ at the doses of 1.0, 1.5, 2.0, and 3.0 mL/rat significantly (p<0.05, p<0.01, p<0.001) improved the levels of TC, LDL-c, TG, HDL-c and VLDL-c. Similarly, PBJ doses starting from 1.0 mL/rat to 3.0 mL/rat reduced the oxidative biomarkers AST, ALT, ALP, and creatinine. The level of HMG-CoA was significantly reduced by PBJ doses 1.5, 2, and 3 ml/rat. A number of compounds have been found to have good pharmacokinetic profile and safety and 4-coumaroylquinic acid exerted the best docking score among them. Thus our findings clearly demonstrated the potential lipid-lowering activities of PBJ both in vivo and in silico studies. PBJ can be a good candidate for the development of antihyperlipidemic medication or as an alternative medicine.

MicroRNA-29b Regulates the Mitochondria-Dependent Apoptotic Pathway by Targeting Bax in Doxorubicin Cardiotoxicity.

BACKGROUND/AIMS: Myocardial apoptosis plays an important role in doxorubicin (Dox) cardiotoxicity. MicroRNA-29 (miR-29) is suggested to function as an anti-fibrotic factor with potential therapeutic effects on cardiac fibrosis. However, it has not been shown whether there is an association between miR-29b and myocardial apoptosis. METHODS: Male Wistar rats were transfected with miR-29b agomir by local delivery to the myocardium prior to Dox treatment. Rat cardiomyocytes were pretreated with miR-29b mimics or inhibitor followed by Dox incubation in vitro. Cardiac function and underlying mechanisms were evaluated by echocardiography, immunofluorescence, flow cytometry, real-time PCR, and western blotting. RESULTS: Our results revealed that miR-29b is the only member of the miR-29 family that was significantly downregulated in myocardium from Dox-treated rats. Delivery of miR-29b agomir to myocardium resulted in a marked improvement of cardiac function. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining showed that rescue of miR-29b expression inhibited Dox-induced myocardial apoptosis, concomitantly with increased Bcl-2 expression and decreased Bax expression and caspase-3 activity. In vitro, miR-29b overexpression mitigated, whereas inhibition of miR-29b promoted, Dox-induced cardiomyocyte apoptosis. Mechanistically, miR-29b negatively regulated Bax expression by directly targeting the 3' untranslated region of Bax. In Dox-treated cardiomyocytes, upregulation of miR-29b resulted in a significant decrease in Bax expression, with an increase in Bcl-2 expression, accompanied by inhibition of mitochondrial membrane depolarization, cytochrome c release, and caspase activation. However, inhibition of miR-29b produced the opposite effects by further augmenting the effects of Dox. CONCLUSIONS: These data demonstrate that miR-29b prevents Dox-induced myocardial apoptosis through inhibition of the mitochondria-dependent pathway by directly targeting Bax, suggesting that miR-29b is a potential novel therapeutic target for the treatment of Dox cardiotoxicity.

Overexpression of TIMP3 Protects Against Cardiac Ischemia/Reperfusion Injury by Inhibiting Myocardial Apoptosis Through ROS/Mapks Pathway.

BACKGROUND/AIMS: Myocardial ischemia/reperfusion (I/R) injury remains a great challenge in clinical therapy. Tissue inhibitor of metalloproteinases 3 (TIMP3) plays a crucial role in heart physiological and pathophysiological processes. However, the effects of TIMP3 on I/R injury remain unknown. METHODS: C57BL/6 mice were infected with TIMP3 adenovirus by local delivery in myocardium followed by I/R operation or doxorubicin treatment. Neonatal rat cardiomyocytes were pretreated with TIMP3 adenovirus prior to anoxia/reoxygenation (A/R) treatment in vitro. Histology, echocardiography, in vivo phenotypical analysis, flow cytometry and western blotting were used to investigate the altered cardiac function and underlying mechanisms. RESULTS: The results showed that upregulation of TIMP3 in myocardium markedly inhibited myocardial infarct areas and the cardiac dysfunction induced by I/R or by doxorubicin treatment. TUNEL staining revealed that TIMP3 overexpression attenuated I/R-induced myocardial apoptosis, accompanied by decreased Bax/Bcl-2 ratio, Cleaved Caspase-3 and Cleaved Caspase-9 expression. In vitro, A/R-induced cardiomyocyte apoptosis was abrogated by pharmacological inhibition of reactive oxygen species (ROS) production or MAPKs signaling. Attenuation of ROS production reversed A/R-induced MAPKs activation, whereas MAPKs inhibitors showed on effect on ROS production. Furthermore, in vivo or in vitro overexpression of TIMP3 significantly inhibited I/R- or A/R-induced ROS production and MAPKs activation. CONCLUSION: Our findings demonstrate that TIMP3 upregulation protects against cardiac I/R injury through inhibiting myocardial apoptosis. The mechanism may be related to inhibition of ROS-initiated MAPKs pathway. This study suggests that TIMP3 may be a potential therapeutic target for the treatment of I/R injury.