Paeoniflorin attenuates atRAL-induced oxidative stress, mitochondrial dysfunction and endoplasmic reticulum stress in retinal pigment epithelial cells via triggering Ca2+/CaMKII-dependent activation of AMPK

Abnormal accumulation of the free-form all-trans-retinal (atRAL), a major intermediate of human visual cycle, is considered to be a key cause of retinal pigment epithelial (RPE) dysfunction in the pathogenesis of retinal degenerative diseases such as age-related macular degeneration (AMD). Paeoniflorin (PF), a monoterpene glucoside isolated from Paeonia lactiflora Pall., has been used in clinical treatment of retinal degenerative diseases in China for several years; however, the underlying mechanism remains unclear. The aim of this study is to investigate the protective effect of PF against atRAL toxicity in human ARPE-19 cells and its molecular mechanism. The results of our study showed that the pre-treatment of PF dose-dependently attenuated atRAL-induced cell injury by the reduction of Nox1/ROS-associated oxidative stress, mitochondrial dysfunction and GRP78-PERK-eIF2α-ATF4-CHOP-regulated endoplasmic reticulum (ER) stress in ARPE-19 cells. Additionally, our data showed that PF mainly exerted its activity via triggering calcium-calmodulin dependent protein kinase II (CaMKII)-mediated activation of AMP-activated protein kinase (AMPK). AMPK inhibition significantly reversed the protective effect of PF against atRAL toxicity in ARPE-19 cells. Overall, our findings provided the novel mechanism of PF protecting human RPE cells, which may prevent the progression of retinal degenerative diseases.

Aidi injection plus platinum-based chemotherapy for stage IIIB/IV non-small cell lung cancer: A meta-analysis of 42 RCTs following the PRISMA guidelines

ETHNOPHARMACOLOGICAL RELEVANCE

Aidi injection is one of the most commonly used Chinese patent medicines for advanced non-small cell lung cancer (NSCLC). It is made from an extraction of Mylabris Phalerata, Radix Astragalus, Radix Ginseng, and Acanthopanax Senticosus.

AIM OF THE STUDY

The objective of this study is to evaluate the efficacy and safety of Aidi injection in combination with platinum-based chemotherapy for stage IIIB/IV NSCLC.

MATERIALS AND METHODS

A systematic review and meta-analysis were performed following the PRISMA (the Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Trials were combined using Review Manager 5.3 and Comprehensive Meta-Analysis(CMA) 2.0. Dichotomous data were expressed as risk ratio (RR) and continuous outcomes as weighted mean difference (WMD), with their 95% confidence intervals (CI) respectively. All randomized controlled trials (RCTs) comparing Aidi injection plus platinum-based chemotherapy versus platinum-based chemotherapy, with efficacy and safety outcomes were selected. Disease Control Rate (DCR) was the primary outcome, Objective Response Rate (ORR), survival rate, quality of life (QOL), and toxic effects were the secondary outcomes.

RESULTS

42 RCTs recruiting 4081 patients with stage IIIB/IV NSCLC were included, with overall low-moderate methodological quality. Compared with platinum-based chemotherapy alone, Aidi injection plus platinum-based chemotherapy can increase relative benefit of DCR (RR = 1.13, 95% CI 1.09-1.16, P < 0.00001), ORR (RR = 1.26, 95% CI 1.18-1.36, P < 0.00001), improve 1-, 2-, 3-year survival rates (RR = 1.14, 95% CI 1.02-1.28, P = 0.03; RR = 1.31, 95% CI 1.05-1.64, P = 0.02; and RR = 1.88, 95% CI 1.32-2.67, P = 0.0005, respectively), QOL (RR = 1.80, 95% CI 1.61-2.01, P < 0.00001), and reduce severe (grade 3 and 4) toxicities by 36% (RR = 0.64, 95% CI 0.58-0.70, P < 0.00001).

CONCLUSIONS

From the available evidence, compared with platinum-based chemotherapy alone, Aidi injection plus platinum-based chemotherapy improves the clinical efficacy and alleviates the toxicity of chemotherapy in patients with stage IIIB/IV NSCLC. However, considering the intrinsic limitations of the included RCTs, well-designed, rigorously performed, high-quality trials are still required to further assess and confirm the results.

Pseudo-Ginsenoside Rh2 induces A549 cells apoptosis via the Ras/Raf/ERK/p53 pathway

Ginsenoside Rh2, a major effective constituent of ginseng, has been suggested to have a pro-apoptotic effect in a variety of cancer cells. Pseudo-Ginsenside-Rh2 (pseudo-G-Rh2) is a novel derivative of ginsenoside Rh2. The aim of the present study was to evaluate the effect of pseudo-G-Rh2 on the apoptosis of lung adenocarcinoma A549 cells. The cytotoxicity of pseudo-G-Rh2 on A549 cells was evaluated using an MTT assay. Apoptosis was detected using DAPI staining and flow cytometry. The expression of apoptosis associated proteins was identified by western blot analysis. The results demonstrated that pseudo-G-Rh2 inhibits the proliferation of A549 cells in a dose-dependent manner. DAPI staining revealed topical morphological changes in apoptotic bodies following pseudo-G-Rh2 treatment. Flow cytometric analysis revealed that the percentage of Annexin V-fluorescein isothiocyanate-positive cells, which are apoptotic, increased with pseudo-G-Rh2 treatment in a dose-dependent manner. Furthermore, treatment with pseudo-G-Rh2 increased the level of reactive oxygen species in A549 cells as well as the activation of caspase-9, caspase-3 and poly ADP-ribose polymerase. Pseudo-G-Rh2 treatment was observed to induce mitochondrial membrane potential loss. Furthermore, the results of western blotting revealed that B-cell lymphoma 2 (Bcl-2) expression was significantly decreased while Bcl-2-associated X protein expression was significantly upregulated in A549 cells with pseudo-G-Rh2 treatment. Pseudo-G-Rh2-induced apoptosis was accompanied by sustained phosphorylation of Ras, Raf, extracellular signal-regulated kinase (ERK) and p53. In conclusion, the results of the present study suggest that pseudo-G-Rh2 induces mitochondrial apoptosis in A549 cells and is responsible for excessive activation of the Ras/Raf/ERK/p53 pathway.

Mito-TEMPO Alleviates Renal Fibrosis by Reducing Inflammation, Mitochondrial Dysfunction, and Endoplasmic Reticulum Stress

Background

Renal fibrosis is a common pathological symptom of chronic kidney disease (CKD). Many studies support that mitochondrial dysfunction and endoplasmic reticulum (ER) stress are implicated in the pathogenesis of CKD. In our study, we investigated the benefits and underlying mechanisms of Mito-TEMPO on renal fibrosis in 5/6 nephrectomy mice.

Methods

Mice were randomly divided into five groups as follows: control group, CKD group, CKD + Mito-TEMPO (1 mg·kg^-1·day^-1) group, CKD + Mito-TEMPO (3 mg·kg^-1·day^-1) group, and Mito-TEMPO group (3 mg·kg^-1·day^-1). Renal fibrosis was evaluated by PAS, Masson staining, immunohistochemistry, and real-time PCR. Oxidative stress markers such as SOD2 activity and MDA level in serum and isolated mitochondria from renal tissue were measured by assay kits. Mitochondrial superoxide production was evaluated by MitoSOX staining and Western blot. Mitochondrial dysfunction was assessed by electron microscopy and real-time PCR. ER stress-associated protein was measured by Western blot.

Results

Impaired renal function and renal fibrosis were significantly improved by Mito-TEMPO treatment. Furthermore, inflammation cytokines, profibrotic factors, oxidative stress markers, mitochondrial dysfunction, and ER stress were all increased in the CKD group. However, these effects were significantly ameliorated in the Mito-TEMPO treatment group.

Conclusions

Mito-TEMPO ameliorates renal fibrosis by alleviating mitochondrial dysfunction and endoplasmic reticulum stress possibly through the Sirt3-SOD2 pathway, which sheds new light on prevention of renal fibrosis in chronic kidney disease.