Antioxidant Sirt1/Akt axis expression in resveratrol pretreated adipose-derived stem cells increases regenerative capability in a rat model with cardiomyopathy induced by diabetes mellitus.

High-glucose (HG) suppresses mesenchymal stem cell (MSC) functions, resulting in a decrease in cardiac regenerative capability for MSC in diabetes mellitus (DM). Resveratrol enhances MSC functions under stress. This study explores if cardiac regenerative capability can be enhanced in MSCs pretreated with resveratrol in DM rats receiving MSCs. In vitro evidence confirms that HG decreases MSCs capability through suppression of survival markers, AMP-activated protein kinase (AMPK)/Sirtuin 1 (Sirt1) axis, and expression of apoptotic markers. All of these markers are improved when MSCs are cocultured with resveratrol. Wistar male rats were randomly divided into Sham, DM (DM rats), DM rats with autologous transplantation of adipose-derived stem cells (DM + ADSC), and DM rats with resveratrol pretreated ADSC (DM + RSVL-ADSC). Compared to the Sham, DM induces pathological pathways (including fibrosis, hypertrophy, and apoptosis) and suppresses survival as well as the AMPK/Sirt1 axis in the DM group. DM + ADSC slightly improves the above pathways whereas DM + RSVL-ADSC significantly improves the above pathways when compared to the DM group. These results illustrate that resveratrol pretreated with MSCs may show clinical potential in the treatment of heart failure in patients with DM.

The combined inhibition of the CaMKIIδ and calcineurin signaling cascade attenuates IGF-IIR-induced cardiac hypertrophy.

Cardiac hypertrophy is a common phenomenon observed in progressive heart disease associated with heart failure. Insulin-like growth factor receptor II (IGF-IIR) has been much implicated in myocardial hypertrophy. Our previous studies have found that increased activities of signaling mediators, such as calcium/calmodulin-dependent protein kinase II (CaMKII) and calcineurin induces pathological hypertrophy. Given the critical roles played by CaMKII and calcineurin signaling in the progression of maladaptive hypertrophy, we anticipated that inhibition of CaMKII and calcineurin signaling may attenuate IGF-IIR-induced cardiac hypertrophy. The current study, therefore, investigated the effects of IGF-IIR activation on the CaMKII and calcineurin signaling and whether the combinatorial inhibition of the CaMKIIδ and calcineurin signaling could ameliorate IGF-IIR-induced pathological hypertrophy. In the present study, we induced IGF-IIR through the cardiomyocyte-specific transduction of IGFIIY27L via adeno-associated virus 2 (AAV2) to evaluate its effects on cardiac hypertrophy. Interestingly, it was observed that the activation of IGF-IIR signaling through IGFIIY27L induces significant hypertrophy of the myocardium and increased cardiac apoptosis and fibrosis. Moreover, we found that Leu27 IGF-II significantly induced calcineurin and CaMKII expression. Furthermore and importantly, the combinatorial treatment with CaMKII and calcineurin inhibitors significantly alleviates IGF-IIR-induced hypertrophic responses. Thus, it could be envisaged that the inhibition of IGF-IIR may serve as a promising candidate for attenuating maladaptive hypertrophy. Both calcineurin and CaMKII could be valuable targets for developing treatment strategies against hypertension-induced cardiomyopathies.

Insulin-like growth factor II receptor-α is a novel stress-inducible contributor to cardiac damage underpinning doxorubicin-induced oxidative stress and perturbed mitochondrial autophagy.

Doxorubicin (DOX) is an anthracycline antibiotic commonly employed for the treatment of various cancers. However, its therapeutic uses are hampered by side effects associated with cumulative doses during the course of treatment. Whereas deregulation of autophagy in the myocardium has been involved in a variety of cardiovascular diseases, the role of autophagy in DOX-induced cardiomyopathy remains debated. Our earlier studies have shown that DOX treatment in a rat animal model leads to increased expression of the novel stress-inducible protein insulin-like growth factor II receptor-α (IGF-IIRα) in cardiac tissues, which exacerbated the cardiac injury by enhancing oxidative stress and p53-mediated mitochondria-dependent cardiac apoptosis. Through this study, we investigated the contribution of IGF-IIRα to dysregulation of autophagy in heart using both in vitro H9c2 cells (DOX treated, 1 µM) and in vivo transgenic rat models (DOX treated, 5 mg/kg ip for 6 wk) overexpressing IGF-IIRα specifically in the heart. We found that IGF-IIRα primarily localized to mitochondria, causing increased mitochondrial oxidative stress that was severely aggravated by DOX treatment. This was accompanied by a significant perturbation in mitochondrial membrane potential and increased leakage of cytochrome c, causing increased cleaved caspase-3 activity. There were significant alterations in phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated Unc-51 like kinase-1 (p-ULK1), PARKIN, PTEN-induced kinase 1 (PINK1), microtubule-associated protein 1 light chain 3 (LC3), and p62 proteins, which were more severely disrupted under the combined effect of IGF-IIRα overexpression plus DOX. Finally, LysoTracker Red staining showed that IGF-IIRα overexpression causes lysosomal impairment, which was rescued by rapamycin treatment. Taken together, we found that IGF-IIRα leads to mitochondrial oxidative stress, decreased antioxidant levels, disrupted mitochondrial membrane potential, and perturbed mitochondrial autophagy contributing to DOX-induced cardiomyopathy.

CHIP attenuates lipopolysaccharide-induced cardiac hypertrophy and apoptosis by promoting NFATc3 proteasomal degradation.

Carboxyl-terminus of Hsc70 interacting protein (CHIP) is a chaperone-dependent E3-ubiquitin ligase with important function in protein quality control system. In the current research endeavor, we have investigated the putative role of CHIP in lipopolysaccharides (LPS)-induced cardiomyopathies. Basically, H9c2 cardiomyoblasts were transfected with CHIP for 24 hr, and thereafter, treated with LPS for 12 hr. Concomitantly, western blot analysis, actin staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and coimmunoprecipitation studies were performed to investigate the underlying intricacies. Interestingly, western blot analysis revealed that the expression of hypertrophy and apoptosis-related proteins were considerably reduced following overexpression of CHIP. Moreover, Actin staining and TUNEL assay further ascertained the attenuation of cardiac hypertrophy and apoptosis following overexpression of CHIP respectively. These aspects instigate the role of CHIP in attenuation of LPS-induced cardiomyopathies. Additionally and importantly, co-immunoprecipitation and western blot studies revealed that CHIP plausibly promotes degradation of nuclear factor of activated T cells 3 (NFATc3) through ubiquitin-proteasomal pathway. Taken together, our study reveals that CHIP attenuates LPS-induced cardiac hypertrophy and apoptosis perhaps by promoting NFATc3 proteasomal degradation.

Upregulation of IGF-IIRα intensifies doxorubicin-induced cardiac damage.

Cardiotoxicity by doxorubicin hampers its therapeutic potential as an anticancer drug, but mechanisms leading to cardiotoxicity remain contentious. Through this study, the functional contribution of insulin-like growth factor receptor type II α (IGF-IIRα) which is a novel stress-inducible protein was explored in doxorubicin-induced cardiac stress. Employing both in vitro H9c2 cells and in vivo transgenic rat models (SD-TG [IGF-IIRα]) overexpressing IGF-IIRα specifically in heart, we found that IGF-IIRα leads to cardiac structural abnormalities and functional perturbations that were severely aggravated by doxorubicin-induced cardiac stress. Overexpression of IGF-IIRα leads to cumulative elevation of stress associated cardiac hypertrophy and apoptosis factors. There was a significant reduction of survival associated proteins p-Akt and estrogen receptor ß/α, and abnormal elevation of cardiac hypertrophy markers such as atrial natriuretic peptide, cardiac troponin-I, and apoptosis-inducing agents such as p53, Bax, and cytochrome C, respectively. IGF-IIRα also altered the expressions of AT1R, ERK1/2, and p38 proteins. Besides, IGF-IIRα also increased the reactive oxygen species production in H9c2 cells which were markedly aggravated by doxorubicin treatment. Together, we showed that IGF-IIRα is a novel stress-induced protein that perturbed cardiac homeostasis and cumulatively exacerbated the doxorubicin-induced cardiac injury that perturbed heart functions and ensuing cardiomyopathy.

E4BP4 inhibits AngII-induced apoptosis in H9c2 cardiomyoblasts by activating the PI3K-Akt pathway and promoting calcium uptake.

The bZIP transcription factor E4BP4 is a survival factor that is known to be elevated in diseased heart and promote cell survival. In this study the role of E4BP4 on angiotensin-II (AngII)-induced apoptosis has been examined in in vitro cell model. H9c2 cardiomyoblast cells that overexpressed E4BP4 were exposed to AngII to observe the cardio-protective effects of E4BP4 on hypertension related apoptosis. The results from TUNEL assays revealed that E4BP4 significantly attenuated AngII-induced apoptosis. Further analysis by Western blot and RT-PCR showed that E4BP4 inhibited AngII-induced IGF-II mRNA expression and cleavage of caspase-3 through the PI3K-Akt pathway. In addition, E4BP4 enhanced calcium reuptake into the sacroplasmic reticulum by down-regulating PP2A and by up-regulating the phosphorylation of PKA and PLB proteins. Our findings indicate that E4BP4 functions as a survival factor in cardiomyoblasts by inhibiting IGF-II transcription and by regulating calcium cycling.

Taiwanin C elicits apoptosis in arecoline and 4-nitroquinoline-1-oxide-induced oral squamous cell carcinoma cells and hinders proliferation via epidermal growth factor receptor/PI3K suppression.

Oral Squamous Cell Carcinoma (OSSC) is a major life-threatening disease with high incidence in the Southeast Asian countries. Chronic exposure to arecoline causes genetic changes in the epithelial cells of the oral mucosa, induces proliferation through activation of the EGF receptor and promotes downstream COX-2 expression. Taiwanin C, a podophyllotoxin derived from Taiwania cryptomerioides Hayata is known to inhibit COX activity and to hinder PGE2 production in macrophages. In this study a tumor cell line T28 and a non-tumor cell line N28 derived from mice OSCC models were used to study the effect of Taiwanin C on PGE2 associated COX-2 expression and cell cycle regulators. Taiwanin C activated p21 protein expression, down-regulated cell cycle regulatory proteins, elevated apoptosis and down-regulated p-PI3K/p-Akt survival mechanism in T28 oral cancer cells. Our results therefore emphasize the therapeutic potential of Taiwanin C against arecoline-induced oral cancer.

The multifaceted link between inflammation and human diseases.

Increasing reports on epidemiological, diagnostic, and clinical studies suggest that dysfunction of the inflammatory reaction results in chronic illnesses such as cancer, arthritis, arteriosclerosis, neurological disorders, liver diseases, and renal disorders. Chronic inflammation might progress if injurious agent persists; however, more typically than not, the response is chronic from the start. Distinct to most changes in acute inflammation, chronic inflammation is characterized by the infiltration of damaged tissue by mononuclear cells like macrophages, lymphocytes, and plasma cells, in addition to tissue destruction and attempts to repair. Phagocytes are the key players in the chronic inflammatory response. However, the important drawback is the activation of pathological phagocytes, which might result from continued tissue damage and lead to harmful diseases. The longer the inflammation persists, the greater the chance for the establishment of human diseases. The aim of this review was to focus on advances in the understanding of chronic inflammation and to summarize the impact and involvement of inflammatory agents in certain human diseases.

Bioactive Peptide Improves Diet-Induced Hepatic Fat Deposition and Hepatocyte Proinflammatory Response in SAMP8 Ageing Mice.

BACKGROUND/AIMS: High-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) poses therapeutic challenges in elderly subjects. Due to lack of efficient drug therapy, plant-based bioactive peptides have been studied as alternative strategy in NAFLD and for less toxicity in elderly. To mimic fatty liver in aging conditions, researchers highly commended the genetically engineered strains SAMP8 (senescence-accelerated mice prone 8). However, there is a paucity of reports about the anti-steatosis effects of bioactive peptides against fatty liver development under a combined action of high-fat diet exposure and aging process. This study was conducted to evaluate the activity of DIKTNKPVIF peptide synthesized from alcalase-generated potato protein hydrolysate (PH), on reducing HFD-driven and steatosis-associated proinflammatory reaction in ageing model. METHODS: Five groups of six-month-old SAMP8 mice (n=4, each) were fed either a normal chow (NC group) for 14 weeks upon sacrifice, or induced with a 6-week HFD feeding, then treated without (HCO group) or with an 8-week simultaneous administration of peptide (HPEP group), protein (HPH group) or probucol (HRX group). Liver organs were harvested from each group for histological analysis and immunoblot assay. RESULTS: In contrast to NC, extensive fat accumulation was visualized in the liver slides of HCO. Following the trends of orally administered PH, intraperitoneally injected peptide reduces hepatic fat deposition and causes at protein level, a significant decrease in HFD-induced proinflammatory mediators p-p38 MAPK, FGF-2, TNF-α, IL-6 with concomitant reactivation of AMPK. However, p-Foxo1 and PPAR-α levels were slightly changed. CONCLUSION: Oral supplementation of PH and intraperitoneal injection of derived bioactive peptide alleviate proinflammatory reaction associated with hepatosteatosis development in elderly subjects, through activation of AMPK.

Lupeol alters ER stress-signaling pathway by downregulating ABCG2 expression to induce Oxaliplatin-resistant LoVo colorectal cancer cell apoptosis.

Colorectal cancer (CRC) is one of the most common cancers and causes of cancer-related death. There are several first-line chemotherapeutic drugs used to treat CRC. Oxaliplatin (OXA) is an alkylating cytotoxic agent that is usually combined with other chemotherapeutic drugs to treat stage II and stage III CRC. However, cancer cells commonly acquire multidrug resistance (MDR), which is a major obstruction to cancer treatment. Recent studies have shown that natural components from traditional Chinese medicine or foods that have many biological functions may be new adjuvant therapies in clinical trials. We challenged LoVo CRC cell lines with OXA in a dose-dependent manner to create an OXA-resistant model. The expression of ABCG2 was significantly higher, and levels of endoplasmic reticulum (ER) stress markers were lower than those Parental cells. However, Lupeol, which is found in fruits and vegetables, has been shown to have bioactive properties, including anti-tumor properties that are relevant to many diseases. In our study, Lupeol downregulated cell viability and activated cell apoptosis. Moreover, Lupeol decreased the expression of ABCG2 and activated ER stress to induce OXA-resistant cell death. Importantly, the anti-tumor effect of Lupeol in OXA-resistant cells was higher than that of LoVo Parental cells. In addition, we also confirmed our results with a xenograft animal model, and the tumor size significantly decreased after Lupeol injections. Our findings show that Lupeol served as a strong chemoresistant sensitizer and could be a new adjuvant therapy method for chemoresistant patients.

Cryptotanshinone (Dsh-003) from Salvia miltiorrhiza Bunge inhibits prostaglandin E2-induced survival and invasion effects in HA22T hepatocellular carcinoma cells.

Human hepatocellular carcinoma (HCC) is currently the second most common cancer and one of the leading causes of cancer-related mortality in Taiwan. Previous reports show that the expression of (E-type prostaglandin 2) EP2 and (E-type prostaglandin 4) EP4 are elevated in HCC and further demonstrate that Prostaglandin E2 (PGE2) induces HA22T cell proliferation and metastasis through EP2 and EP4 receptor. Danshen (root of Salvia miltiorrhiza Bunge) is a very important and popular traditional Chinese herbal medicine which is widely and successfully used against breast cancer, leukemia, pancreatic cancer, and head and neck squamous carcinoma cells. In this study, we used Cryptotansinone (Dsh-003) (MW 269.14) from Danshen to investigate their effect and corresponding mechanism of action in PGE2-treated HA22T cells. Dsh-003 inhibited HA22T cell viability and further induced cell apoptosis in PGE2-treated HA22T cells. Furthermore, Dsh-003 inhibited EP2, EP4, and their downstream effector such as p-PI3K and p-Akt expression in HA22T hepatocellular carcinoma cells. We also observed that Dsh-003 blocked PGE2-induced cell migration by down-regulating PGE2-induced ß-catenin expression and by up-regulating E-cadherin and GSK3-ß expression. All these findings suggest that Dsh-003 inhibit human HCC cell lines and could potentially be used as a novel drug for HCC treatment.

Adipose-derived stem cells decrease cardiomyocyte damage induced by porphyromonas gingivalis endotoxin through suppressing hypertrophy, apoptosis, fibrosis, and MAPK markers.

Heart failure is one of the complications related to periodontal disease. In addition to drugs or herbal medicines, stem cell therapy shows potential in the treatment of cardiomyopathy. This study investigates if stem cells exhibit beneficial effects on cardiomyocyte damage induced by porphyromonas gingivalis endotoxin (Pg-LPS). From the experimental results we find that Pg-LPS reduce cardiomyocyte viability via the activation of apoptosis, hypertrophy, fibrosis and MAPK signaling. Pg-LPS damaged cardiomyocytes co-cultured with adipose-derived stem cells (ADSC) increases cardiomyocyte viability through suppressing the pathological markers described above. Further evidence implies that survival marker, IGF1, secreted from ADSC, may play an important role in the Pg-LPS induced protective effect on cardiomyocyte damage.

The preventive effects of edible folic acid on cardiomyocyte apoptosis and survival in early onset triple-transgenic Alzheimer's disease model mice.

In recent years, neuropathological and epidemiological studies have indicated an association between Alzheimer's disease (AD) and several cardiovascular risk factors. In this study, the cardio-protective effects of folic acid (FA) in early stage AD was elucidated using a triple-transgenic (3xTg) Alzheimer's mouse model. Eleven-month-old C57BL/6 mice and 3xTg mice were assigned to five groups. During the four-month treatment period, the low-FA treatment group received FA through their diet, and the high-FA treatment groups received 3 mg/dl folate in drinking water and were also gastric-fed 1.2 mg/kg folate every day. In the C57B1/6J mice, treatment with high doses of FA (HFA) did not show any considerable effect compared to the control group or the low-dose dietary FA treatment group. However, Alzheimer's mice treated with HFA showed enhanced cardio-protection. Western blot analysis revealed that FA treatment restored SIRT1 expression, which was suppressed in 3xTg mice, through enhanced AMPK expression. FA significantly enhanced the IGF1 receptor survival mechanism in the hearts of the 3xTg mice and suppressed the expression-intrinsic and extrinsic apoptosis-associated proteins. The results suggest that FA intake may significantly alleviate cellular pathological events in the heart associated with AD.

Fenofibrate induced PPAR alpha expression was attenuated by oestrogen receptor alpha overexpression in Hep3B cells.

The physiological regulation of Oestrogen receptor α (ERα) and peroxisome proliferator-activated receptor alpha (PPARα) in Hepatocellular carcinoma (HCC) remains unknown. The present study we first treat the cells with fenofibrate and further investigated the possible mechanisms of 17ß-estradiol (E2 ) and/or ERα on regulating PPARα expression. We also found higher PPARα expression in the tumor area than adjacent areas and subsequently compared PPARα expression in four different hepatic cancer cell lines. Hep3B cells were found to express more PPARα than the other cell lines. Using the PPARα agonist fenofibrate, we found that fenofibrate increased Hep3B cell proliferation efficiency by increasing cell cycle proteins, such as cyclin D1 and PCNA, and inhibiting p27 and caspase 3 expressions. Next, we performed transient transfections and immuno-precipitation studies using the pTRE2/ERα plasmid to evaluate the interaction between ERα and PPARα. ERα interacted directly with PPARα and negatively regulated its function. Moreover, in Tet-on ERα over-expressed Hep3B cells, E2 treatment inhibited PPARα, its downstream gene acyl-CoA oxidase (ACO), cyclin D1 and PCNA expression and further increased p27 and caspase 3 expressions. However, over-expressed ERα plus 17-ß-estradiol (10-8 M) reversed the fenofibrate effect and induced apoptosis, which was blocked in ICI/melatonin/fenofibrate-treated cells. This study illustrates that PPARα expression and function were negatively regulated by ERα expression in Hep3B cells.

Anti-Apoptosis and Anti-Fibrosis Effects of Eriobotrya Japonica in Spontaneously Hypertensive Rat Hearts.

Myocardial apoptosis and fibrosis represent important contributing factors for development of hypertension-induced heart failure. The present study aims to investigate the potential effects of Eriobotrya japonica leaf extract (EJLE) against hypertension-induced cardiac apoptosis and fibrosis in spontaneously hypertensive rats (SHRs). Twelve-week-old male rats were randomly divided into four different groups; control Wistar Kyoto (WKY) rats, hypertensive SHR rats, SHR rats treated with a low dose (100 mg/kg body weight) of EJLE and SHR rats treated with a high dose (300 mg/kg body weight) of EJLE. Animals were acclimatized for 4 weeks and thereafter were gastric fed for 8 weeks with two doses of EJLE per week. The rats were then euthanized following cardiac functional analysis by echocardiography. The cardiac tissue sections were examined by Terminal Deoxynucleotidyl Transferase-Mediated Deoxyuridine Triphosphate (dUTP) Nick End-Labeling (TUNEL) assay, histological staining and Western blotting to assess the cardio-protective effects of EJ in SHR animals. Echocardiographic measurements provided convincing evidence to support the ability of EJ to ameliorate crucial cardiac functional characteristics. Furthermore, our results reveal that supplementation of EJLE effectively attenuated cardiac apoptosis and fibrosis and also enhanced cell survival in hypertensive SHR hearts. Thus, the present study concludes that EJLE potentially provides cardio-protective effects against hypertension-induced cardiac apoptosis and fibrosis in SHR animals.

Estrogen and/or Estrogen Receptor α Inhibits BNIP3-Induced Apoptosis and Autophagy in H9c2 Cardiomyoblast Cells.

The process of autophagy in heart cells maintains homeostasis during cellular stress such as hypoxia by removing aggregated proteins and damaged organelles and thereby protects the heart during the times of starvation and ischemia. However, autophagy can lead to substantial cell death under certain circumstances. BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3), a hypoxia-induced marker, has been shown to induce both autophagy and apoptosis. A BNIP3-docked organelle, e.g., mitochondria, also determines whether autophagy or apoptosis will take place. Estrogen (E2) and estrogen receptor (ER) alpha (ERα) have been shown to protect the heart against mitochondria-dependent apoptosis. The aim of the present study is to investigate the mechanisms by which ERα regulates BNIP3-induced apoptosis and autophagy, which is associated with hypoxic injury, in cardiomyoblast cells. An in vitro model to mimic hypoxic injury in the heart by engineering H9c2 cardiomyoblast cells to overexpress BNIP3 was established. Further, the effects of E2 and ERα in BNIP3-induced apoptosis and autophagy were determined in BNIP3 expressing H9c2 cells. Results from TUNEL assay and Immunoflourecense assay for LC3 puncta formation, respectively, revealed that ERα/E2 suppresses BNIP3-induced apoptosis and autophagy. The Western blot analysis showed ERα/E2 decreases the protein levels of caspase 3 (apoptotic marker), Atg5, and LC3-II (autophagic markers). Co-immunoprecipitation of BNIP3 and immunoblotting of Bcl-2 and Rheb showed that ERα reduced the interaction between BNIP3 and Bcl-2 or Rheb. The results confirm that ERα binds to BNIP3 causing a reduction in the levels of functional BNIP3 and thereby inhibits cellular apoptosis and autophagy. In addition, ERα attenuated the activity of the BNIP3 promoter by binding to SP-1 or NFκB sites.

High density lipoprotein (HDL) reverses palmitic acid induced energy metabolism imbalance by switching CD36 and GLUT4 signaling pathways in cardiomyocyte.

In our previous study palmitic acid (PA) induced lipotoxicity and switches energy metabolism from CD36 to GLUT4 in H9c2 cells. Low level of high density lipoprotein (HDL) is an independent risk factor for cardiac hypertrophy. Therefore, we in the present study investigated whether HDL can reverse PA induced lipotoxicity in H9c2 cardiomyoblast cells. In this study, we treated H9c2 cells with PA to create a hyperlipidemia model in vitro and analyzed for CD36 and GLUT4 metabolic pathway proteins. CD36 metabolic pathway proteins (phospho-AMPK, SIRT1, PGC1α, PPARα, CPT1ß, and CD36) were decreased by high PA (150 and 200 µg/µl) concentration. Interestingly, expression of GLUT4 metabolic pathway proteins (p-PI3K and pAKT) were increased at low concentration (50 µg/µl) and decreased at high PA concentration. Whereas, phospho-PKCζ, GLUT4 and PDH proteins expression was increased in a dose dependent manner. PA treated H9c2 cells were treated with HDL and analyzed for cell viability. Results showed that HDL treatment induced cell proliferation efficiency in PA treated cells. In addition, HDL reversed the metabolic effects of PA: CD36 translocation was increased and reduced GLUT4 translocation, but HDL treatment significantly increased CD36 metabolic pathway proteins and reduced GLUT4 pathway proteins. Rat neonatal cardiomyocytes showed similar results. In conclusion, HDL reversed palmatic acid-induced lipotoxicity and energy metabolism imbalance in H9c2 cardiomyoblast cells and in neonatal rat cardiomyocyte cells.

Short-Term Hypoxia Reverses Ox-LDL-Induced CD36 and GLUT4 Switching Metabolic Pathways in H9c2 Cardiomyoblast Cells.

High levels of circulating low-density lipoproteins (LDL, plasma proteins that carry cholesterol and triglycerides) are associated with type 2 diabetes, arteriosclerosis, obesity, and hyperlipidemia. In the heart, the accumulation of oxidized low-density lipoprotein (Ox-LDL) has been proposed to play a role in the development of cardiovascular disease. We obtain cholesterol from animals and animal-derived foods such as milk, eggs, and cheese. In previous studies, the ratio of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) was shown to be important for our health. High levels of LDL cholesterol lead to atherosclerosis, increasing the risk of heart attack and ischemic stroke. In this study, we utilized Ox-LDL-treated H9c2 cardiomyoblast cells as a simulated hyperlipidemia model. CD36 metabolism pathway proteins (phospho-Akt, SIRT1, PGC1α, PPARα, CPT1ß, and CD36) increased at low doses of Ox-LDL. However, high doses (150 and 200 mg/dL) of Ox-LDL reduced the levels of these proteins. Interestingly, expression of GLUT4 metabolism pathway proteins (phospho-PKCζ) were reduced at low doses, while the expression of phospho-AMPK, phospho-PI3K, phospho-PKCζ, GLUT4, and PDH proteins increased at high doses. Ox-LDL acute treatment induces apoptosis in cardiomyocytes as evidenced by apoptotic nuclei apparition, caspase-3 activation, and cytochrome c release from mitochondria. In our results, Ox-LDL induced lipotoxicity in cardiomyocytes, and subsequent exposure to short-term hypoxia or reversed the Ox-LDL-induced metabolic imbalance. The same result was obtained with the pharmacological activation of SIRT1 by resveratrol and si-PKCζ. The mechanism of metabolic switching during Ox-LDL lipotoxicity seems to be mediated by SIRT1 and PKC ζ. J. Cell. Biochem. 118: 3785-3795, 2017. © 2017 Wiley Periodicals, Inc.

Tanshinone-induced ERs suppresses IGFII activation to alleviate Ang II-mediated cardiac hypertrophy.

Cardiomyopathy involves changes in myocardial ultrastructure and cardiac hypertrophy. Angiotensin II (AngII) has previously been shown to stimulate the expression of IGF-2 and IGF-2R in H9c2 cardiomyoblasts and increase of blood pressure, and cardiac hypertrophy. Estrogen receptors (ERs) exert protective effects, such as anti-hypertrophy in cadiomyocytes. Tanshinone IIA (TSN), a main active ingredient from a Chinese medical herb, Salvia miltiorrhiza Bunge (Danshen), was shown to protect cardiomyocytes hypertrophy by different stress signals. We aimed to investigate whether TSN protected H9c2 cardiomyocytes from AngII-induced activation of IGF-2R pathway and hypertrophy by mediating through ERs. AngII resulted in H9c2 cardiomyoblast hypertrophy and increased inflammatory molecular markers. These were down-regulated by TSN via estrogen receptors. AngII resulted in elevation in MAPKs, IGF-2R and hypertrophic protein markers. These, again, were reduced by addition of the phytoestrogen with activation of ERs. Finally, AngII induced phosphorylation of heat shock factor-1 (HSF1) and decreased sirtuin-1 (SIRT1). In addition, AngII also caused an increase in distribution of IGF-2R molecules on cell membrane. In contrast, TSN reduced HSF1 phosphorylation and cell surface IGF-2R while elevating SIRT1 via ERs. TSN was capable of attenuating AngII-induced IGF-2R pathway and hypertrophy through ERs in H9c2 cardiomyoblast cells.

Attenuation of the LPS-induced, ERK-mediated upregulation of fibrosis-related factors FGF-2, uPA, MMP-2, and MMP-9 by Carthamus tinctorius L in cardiomyoblasts.

Severe and potentially fatal hypotension and cardiac contractile dysfunction are common symptoms in patients with sepsis. LPS was previously found to dramatically upregulate expression of fibrosis-related factors FGF-2, uPA, MMP-2, and MMP-9 in primary cardiac fibroblasts. MMPs are capable of denaturing and degrading fibrillar collagens and other components of the extracellular matrix (ECM). Studies have shown that dysregulation of expression of MMPs is associated with development of myocardial extracellular matrix remodeling and cardiac fibrosis, which contribute to progression of heart failure. In this study, H9c2 cells and cardiac fibroblasts were divided into five treatment groups: control, LPS (1 µg/mL) and three concentrations of FCEtOH (Carthami Flos ethanolic extract) (31.25, 62.5, and 125 µg/mL). Phosphorylation of ERK-1/2 was observed to be rapidly induced upon treatment with LPS. In contrast, it was significantly suppressed by the administration of FCEtOH (125 µg/mL). Effects of FCEtOH on LPS-induced MMP-2 and MMP-9 expression in H9c2 cells occurred directly through ERK1/2 were determined. H9c2 cells were therefore pretreated with EGF-R to activate ERK pathway. Both protein levels of MMP-2 and MMP-9 and immunefluorescent signals of MMP-9 were significantly enhanced by EGFR. In contrast, MMP-2 and MMP-9 were significantly reduced after FCEtOH administration. Based on these findings, the authors concluded that FCEtOH elicits a protective effect against LPS-induced cardio-fibrosis through the ERK1/2 pathway. Carthamus tinctorius L may potentially serve as a cardio-protective agent against LPS- induced cardiac fibrosis. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 754-763, 2017.