Abstract Ganoderic acid A (GAA) is one of the most abundant triterpenoids in Ganoderma lucidum and has protective effect on several vascular diseases. However, the effect of GAA on pulmonary arterial hypertension (PAH) has not been reported. The aim of this study was to investigate the effect of the GAA on the hypoxia-induced phenotypic modulation of PASMCs and the involved transduction pathway. Primary rat pulmonary artery smooth muscle cells (PASMCs) were isolated and cultured under hypoxia condition to induce phenotypic modulation. Our results showed that hypoxia significantly increased the proliferation and migration of PASMCs, as well as inhibited the apoptosis of PASMCs, which were blocked by GAA treatment. In addition, hypoxia-induced dedifferentiation of PASMCs was prevented by GAA with increased the expression levels of myocardin and calponin, and decreased the expression of osteopontin (OPN). Furthermore, GAA suppressed the hypoxia-induced expression of p-PI3K and p-Akt in PASMCs. Treatment with IGF-1 reversed the effects of GAA on proliferation, migration, apoptosis and dedifferentiation in hypoxia-treated PASMCs. Taken together, these findings demonstrated that GAA suppresses the phenotypic modulation of PASMCs through the inactivation of PI3K/Akt pathway. Thus, GAA may be a potent therapeutic agent for PAH in future clinical practice.

In this work, alginate-whey protein was used as wall materials for encapsulating Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus). The characteristics of encapsulated and free L. bulgaricus showed that the free L. bulgaricus lost viability after 1 min exposure to simulated gastric fluid (SGF) at pH 2.0 and 2.5. However, the viability of encapsulated L. bulgaricus did not decrease in SGF at pH 2.5 for 2 h incubation. The viable numbers of encapsulated L. bulgaricus decreased less than 1.0 log unit for 2 h incubation in SGF at pH 2.0. For bile stability, only 1.2 log units and 2.0 log units viability of the encapsulated L. bulgaricus was lost in 1 and 2% bile for 1 h exposure, respectively, compared with no survival of free L. bulgaricus under the same conditions. Encapsulated L. bulgaricus was completely released from the microspheres in simulated intestinal fluid (SIF, pH 6.8) in 3 h. The viability of the encapsulated L. bulgaricus retained more 8.0 log CFU/g after stored at 4°C for four weeks. However, for free L. bulgaricus, only around 3.0 log CFU/mL was found at the same storage conditions. Results showed that the encapsulation could improve the stability of L. bulgaricus.

Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein that mediates both NADH-oxidizing and caspase-independent apoptosis. Further, the proapoptotic activity of AIF is located in the C-terminus of AIF, although the precise minimum sequence responsible for apoptosis induction remains to be investigated. In the present study, we generated two truncated AIFs, AIFΔ1-480-FLAG, which is a FLAG-tagged C-terminal peptide comprising amino acids from 481 to 613, and AIF360-480 containing amino acids from 360 to 480 of AIF. We used confocal microscopy to demonstrate that both the truncated proteins are expressed and located in the cytoplasm of transfected cells. AIFΔ1-480 but not AIF360-480 induces apoptosis in transfected cells. We also found that the expression of AIFΔ1-480 could initiate the release of cytochrome c from the mitochondria. The suppression of caspase-9 via siRNA blocked the proapoptotic activity of AIFΔ1-480. Therefore, AIFΔ 1-480 is sufficient for inducing caspase-9-dependent apoptotic signaling, probably by promoting the release of cytochrome c. At last, we generated a chimeric immuno-AIFΔ 1-480 protein, which comprised an HER2 antibody, a Pseudomonas exotoxin A translocation domain and AIFΔ 1-480. Human Jurkat cells transfected with the immuno-AIFΔl-480 gene could express and secrete the chimeric protein, which selectively recognize and kill HER2-overexpressing tumor cells. Our study demonstrates the feasibility of the immuno-AIFΔl-480 gene as a novel approach to treating HER2-overexpressing cancers.