Pinoresinol diglucoside (PDG) attenuates cardiac hypertrophy via AKT/mTOR/NF-κB signaling in pressure overload-induced rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Pinoresinol diglucoside (PDG), the active compound extracted from Eucommia ulmoides, Styrax sp. and Forsythia suspensa, plays the roles in regulating hypertension, inflammation and oxidative stress. AIMS: Considering that hypertension and inflammation has been proved to contribute to cardiac remodeling, we tested the effects of PDG on cardiac hypertrophy (CM). METHODS: Male Sprague Dawley (SD) rats were used to construct hypertrophic rats by partial abdominal aortic constriction (AAC)-surgery. PDG solution (2 mg/ml) was used to treat AAC-induced rats by intraperitoneal injection at low dose (L-PDG, 2.5 mg/kg per day), medium dose (M-PDG, 5 mg/kg per day), and high dose (H-PDG, 7.5 mg/kg per day) for 3 weeks post AAC-surgery. CM was evaluated by the ratio of left ventricular weight to body weight ratio (LVW/BW), left ventricular wall thickness by H&E staining, and collagen content deposit by Masson's staining. Further, isoproterenol (ISO) and phenylephrine (PE) were used to produce cellular models of CM in neonatal rat ventricular cardiomyocytes (NRVMs). PDG pre-treated NRVMs 2 h at low dose (L-PDG, 2.5 µg/ml), medium dose (M-PDG, 5 µg/ml), and high dose (H-PDG, 7.5 µg/ml) for 24 h with or without PE- and ISO-stimulation. CM was evaluated by the expressions of hypertrophic biomarkers. Next, the hypertrophic biomarkers and pro-inflammatory cytokines were measured using quantitative real-time PCR (qRT-PCR), the expressions of protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/transcription factor nuclear factor-kappa B (NF-kB) signaling pathway were determined by Western blotting. RESULTS: PDG treatment prevented cardiac histomorphology damages, decreased upregulations of hypertrophic biomarkers, and prevented fibrosis and inflammation after pressure overload resulting from AAC-surgery. Consistently, PDG remarkably inhibited the changes of cardiomyocyte hypertrophic biomarkers and inflammatory responses in cellular models of CM. Interestingly, PDG administration inhibited the activation of AKT/mTOR/NF-kB signaling pathway both in vivo and in vitro. CONCLUSIONS: PDG prevents AAC-induced CM in vivo, PE- and ISO-induced CM in vitro. The AKT/mTOR/NF-kB signaling pathway could be the potential therapeutic target involved in the protection of PDG. These findings provide novel evidence that PDG might be a promising therapeutic strategy for CM.

Calycosin directly improves perivascular adipose tissue dysfunction by upregulating the adiponectin/AMPK/eNOS pathway in obese mice.

Perivascular adipose tissue (PVAT) loses its anti-contractile activity in obesity. Calycosin, the major bioactive isoflavonoid, was shown to protect endothelial function. However, effects of calycosin on PVAT function in obesity remain unclear. We aimed to investigate the effects of calycosin on the anti-contractile activity of PVAT in obese mice and its potential mechanisms. Obesity in mice was induced with a high-fat diet, with or without calycosin treatment. Thoracic aorta responses to phenylephrine were determined. AMP protein kinase (AMPK) and endothelial nitric oxide synthase (eNOS) levels were analyzed by western blotting. Adiponectin, TNF-α levels and superoxide production were measured in the PVAT. Calycosin treatment significantly increased the anti-contractile response of PVAT, which was impaired in obese mice. This beneficial effect of calycosin was eliminated by treatments of blocking adiponectin, AMPK or eNOS. Similar results were observed for calycosin treatment ex vivo. Treatment of obese mice with calycosin significantly increased adiponectin levels, activated AMPK and eNOS phosphorylation and reduced superoxide production and TNF-α levels in PVAT. Our results indicated that calycosin restored PVAT induced anti-contractile activity and affected PVAT function through the adiponectin/AMPK/eNOS pathway in obese mice.

Evaluation of velvet antler total protein effect on bone marrow­derived endothelial progenitor cells.

Lu Rong, velvet antler (VA), is a traditional Chinese medicine, which is used as a food supplement and therapeutic drug in China, Japan, Russia, New Zealand and Southeast Asia. The regenerative characteristics of VA have resulted in great research interest, particularly regarding the fields of organ grafting and stem cell differentiation. Various VA proteomic studies verified that proteins act as the primary bioactive components of VA. The present study aimed to investigate if VA proteins (VA­pro) influence endothelial progenitor cell (EPC) viability. Various methods have previously been used to investigate VA­pro, including freeze­drying technology, ultrasonic wave methods, high performance liquid chromatography­mass spectrometry, EPCs extraction and culture. Results demonstrated that VA­pro promoted EPCs proliferation and migration, particularly at a concentration of 1 mg/ml. Furthermore, VA­pro increased the activation level of Notch1 intracellular domain and Hes1, and the level of phosphorylated­Akt and phosphorylated­mechanistic target of rapamycin. VA­pro may therefore affect EPC viability via regulation of the Notch and Akt signaling pathways. The present study revealed the effects and potential molecular mechanism of VA­pro on EPCs, and suggested an association between VA regeneration characteristics and the optimization of EPC viability. These findings may contribute to EPC transplantation research and aid in providing a novel treatment method for vascular diseases in the future.

Hydroxysafflor Yellow A Alleviates Lipopolysaccharide-Induced Acute Respiratory Distress Syndrome in Mice.

Hydroxysafflor yellow A (HSYA) is an effective ingredient of the Chinese herb Carthamus tinctorius L. The present study investigated the protective effect of HSYA on lipopolysaccharide (LPS)-induced acute respiratory distress syndrome in mice, and the underlying mechanisms involved. HSYA (14, 28, 56 mg/kg) was intraperitoneally injected to mice once daily from day 1 to 10 after LPS administration. HSYA attenuated the body weight loss, the augmented left index and the increase of pathologic changes in pulmonary inflammation caused by LPS. Treatment with HSYA also alleviated increased expressions of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, transforming growth factor (TGF)-ß1, collagen (Col) I, Col III, α-smooth muscle actin (α-SMA), myeloid differentiation (MD)-2, Toll-like receptor 4 (TLR4) and cluster differentiation (CD)14 at the mRNA (RT-PCR) and protein levels (Western blot and enzyme-linked immuno sorbent assay). Moreover, HSYA inhibited the elevated levels of nuclear factor (NF)-κB and α-SMA in lung tissue (immunohistochemistry), and alleviated the slight collagen deposition in pulmonary tissues (Masson's trichrome staining). HSYA inhibited the specific binding of fluorescein isothiocyanate (FITC)-LPS on human lung epithelial cell line (A549) or human umbilical vein cell line (Eahy926) cells (flow cytometry). These findings suggested that HSYA has a protective effect on acute respiratory distress syndrome (ARDS) induced by LPS through blocking the TLR4/NF-κB pathway, and that the TLR4 receptor might be a target of HSYA on the cell membrane.