Reversion of left ventricle remodeling in spontaneously hypertensive rats by valsartan is associated with the inhibition of caspase-3, -8 and -9 activities

Ultrasonic-Assisted Enzymolysis Extraction and Protective Effect on Injured Cardiomyocytes in Mice of Flavonoids from Prunus mume Blossom

Prunus mume blossom is an edible flower that has been used in traditional Chinese medicine for thousands of years. Flavonoids are one of the most active substances in Prunus mume blossoms. The optimal ultrasonic-assisted enzymatic extraction of flavonoids from Prunus mume blossom (FPMB), the components of FPMB, and its protective effect on injured cardiomyocytes were investigated in this study. According to our results, the optimal extraction process for FPMB is as follows: cellulase at 2.0%, ultrasonic power at 300 W, ultrasonic enzymolysis for 30 min, and an enzymolysis temperature of 40 °C. FPMB significantly promoted the survival rate of cardiomyocytes and reduced the concentration of reactive oxygen species (ROS). FPMB also improved the activities of proteases caspase-3, caspase-8, and caspase-9 in cardiomyocytes. The cardiomyocyte apoptosis rate in mice was significantly reduced by exposure to FPMB. These results suggest that the extraction rate of FPMB may be improved by an ultrasonic-assisted enzymatic method. FPMB has a protective effect on the injured cardiomyocytes.

Icarrin prevents cardiomyocyte apoptosis in spontaneously hypertensive rats by inhibiting endoplasmic reticulum stress pathways

OBJECTIVES

This study aimed to explore whether icarrin (ICA) can protect cardiomyocytes from hypertension-induced damage by inhibiting endoplasmic reticulum stress (ERS).

METHODS

Spontaneously hypertensive rats (SHRs) were orally administered water or ICA at 10, 20 and 40 mg/kg once daily for 12 weeks, and Wistar-Kyoto (WKY) rats were used as control. Changes in the growth and blood pressure of rats were assessed. Cardiac function was determined by ultrasound and the left ventricle mass was calculated. Myocardial tissue structure was assessed by haematoxylin and eosin staining, cardiomyocyte apoptosis was observed by TUNEL staining and the expression of ERS-related proteins was determined by western blotting.

RESULTS

In the SHR group, blood pressure was significantly high, left ventricular function decreased and left ventricular mass index increased. Additionally, left ventricular cardiomyocyte hypertrophy, disordered myofilament arrangement and increased cardiomyocyte apoptosis were observed by histological staining. ERS-induced proteins associated with apoptosis, including GRP78, PERK, ATF-6, ATF-4, CHOP, DR5, Caspase 12, c-JUN and ASK-1 were found to be highly expressed. ICA treatment reduced blood pressure and regulated the expression of proteins induced by ERS. Cardiomyocyte apoptosis decreased and left ventricular function improved.

CONCLUSIONS

ICA can inhibit ERS-induced apoptosis of cardiomyocytes and protect ventricular function in SHR.

Antioxidant Properties of Alpha-Lipoic (Thioctic) Acid Treatment on Renal and Heart Parenchyma in a Rat Model of Hypertension

Renal and cardiac impairments are frequent events in the presence of hypertension. Organ damage is mainly linked to oxidative stress due to high blood pressure and may be reduced by antioxidant supplementation. Alpha-lipoic acid (ALA) is one of most effective antioxidants. It is widely used as a nutritional supplement in a racemic mixture (+/–), even though the (+)-enantiomer is biologically active. This study was designed to investigate the effect of treatment with (+/–)-ALA and its enantiomers on renal and heart parenchyma in spontaneously hypertensive rats (SHR), using immunochemical and immunohistochemical techniques. The results confirmed that the oxidative mechanisms of organ alterations, due to hypertension, and characterized by glomerular and tubular lesions, left ventricular hypertrophy, and fibrosis but not by apoptosis were accompanied by proteins’ and nucleic acids’ oxidation. We found greater effectiveness of (+)-ALA compared to (+/−)-ALA in reducing oxidative stress, cardiac and renal damages in SHR. To conclude, these data propose (+)-ALA as one of the more appropriate antioxidant molecules to prevent renal and cardiac alterations associated with hypertension.

Candesartan and valsartan Zn(ii) complexes as inducing agents of reductive stress: mitochondrial dysfunction and apoptosis

Candesartan and valsartan Zn(ii) complexes as inducing agents of reductive stress, including mitochondrial dysfunction and apoptosis.

Multiomic blood correlates of genetic risk identify presymptomatic disease alterations

Transitions from health to disease are characterized by dysregulation of biological networks under the influence of genetic and environmental factors, often over the course of years to decades before clinical symptoms appear. Understanding these dynamics has important implications for preventive medicine. However, progress has been hindered both by the difficulty of identifying individuals who will eventually go on to develop a particular disease and by the inaccessibility of most disease-relevant tissues in living individuals. Here we developed an alternative approach using polygenic risk scores (PRSs) based on genome-wide association studies (GWAS) for 54 diseases and complex traits coupled with multiomic profiling and found that these PRSs were associated with 766 detectable alterations in proteomic, metabolomic, and standard clinical laboratory measurements (clinical labs) from blood plasma across several thousand mostly healthy individuals. We recapitulated a variety of known relationships (e.g., glutamatergic neurotransmission and inflammation with depression, IL-33 with asthma) and found associations directly suggesting therapeutic strategies (e.g., Ω-6 supplementation and IL-13 inhibition for amyotrophic lateral sclerosis) and influences on longevity (leukemia inhibitory factor, ceramides). Analytes altered in high-genetic-risk individuals showed concordant changes in disease cases, supporting the notion that PRS-associated analytes represent presymptomatic disease alterations. Our results provide insights into the molecular pathophysiology of a range of traits and suggest avenues for the prevention of health-to-disease transitions.

Tandospirone enhances the anti-myocardial fibrosis effect of valsartan in spontaneously hypertensive rats

PURPOSE

Myocardial fibrosis (MF) is an unavoidable complication in patients with hypertensive heart disease. Valsartan, a widely used antihypertensive drug, was reported to inhibit MF. Deficiency in the 5-hydroxytryptamine (5-HT, serotonin) transporter gene has been proven to cause MF. Long-term sympathetic nerve excitability activates renin angiotensin aldosterone system leading to MF. Tandospirone, a partial agonist of the 5-HT1A receptor, has been commonly used to relieve psychiatric symptoms. However, there is limited evidence on the combination of valsartan and tandospirone for the treatment of MF. Therefore, we investigated the synergistic effect of tandospirone on the anti-MF activity of valsartan in spontaneously hypertensive rats (SHRs).

METHODS

Systolic blood pressure (SBP) of SHRs (12-week-old) was measured weekly using the tail-cuff method for eight weeks; the left ventricular was collected and weighted for calculation of the left ventricular mass index (LVMI). The myocardial histopathology of left ventricle was evaluated in rats by hematoxylin and eosin (H&E) and Mason's trichrome staining assays. The mRNA and protein expressions of transforming growth factor β (TGF-β1), Sma- and Mad-related protein 3 (Smad3), and fibronectin (Fn) were investigated by real time PCR, immunohistochemistry, and Western blotting analysis, respectively.

RESULTS

Tandospirone (40 mg/kg) could significantly improve the effect of valsartan (30 mg/kg) in decreasing the SBP of SHRs and lower the ratio of the LVMI in SHRs, compared to that of rats treated with valsartan or tandospirone alone. Tandospirone could also enhance the valsartan-induced reduction in collagen deposition in the myocardial tissues of SHRs. Furthermore, tandospirone could enhance the effect of valsartan on downregulating the expression levels of TGF-β1, Smad3, and Fn at both mRNA and protein levels.

CONCLUSION

We report for the first time that tandospirone could improve the anti-MF efficacy of valsartan via the TGF-β1/Smad3 signaling pathway in SHRs. Our findings may provide valuable insight into the scientific rationale for combining tandospirone and valsartan in the treatment of MF clinically.

Effect of the Single-Pill Amlodipine/Valsartan Combination on Hypertrophy and Myocardial Deformation Characteristics in Middle-Aged Patients with Essential Arterial Hypertension

Aim. To investigate the impact of amlodipine/valsartan single-pill combination (A/V SPC) on left ventricular hypertrophy (LVH) and left ventricular (LV) myocardial strain and stiffness parameters in naїve middle-aged patients with stage II grade 1-2 essential arterial hypertension (EAH).Material and methods. A group of patients with stage II grade 1-2 EAH who had not previously received regular antihypertensive treatment (AHT) [n=38; mean age 49.7±7.0 years] was retrospectively formed. All the patients were treated with A/V SPC and all of them achieved target office blood pressure (BP) (less than 140/90 mm Hg). And after 12 weeks follow-up (since the time of reaching the target BP) the AHT effectiveness assessment, its impact on LVH and LV myocardial strain and stiffness parameters (general clinical data, ambulatory blood pressure monitoring, conventional and 2D-speckle tracking echocardiography) were performed in all included patients.Results. The number of patients with LVH significantly (p=0.039) decreased from 25 individuals (65.8%) at baseline to 15 patients (39.5%) at the end of follow-up. Among patients with LVH at baseline after the treatment with A/V SPC significantly decreased (p<0.001 for all) interventricular septum thickness (from 1.36±0.19 to 1.28±0.18 cm), LV posterior wall thickness (from 1.08±0.09 to 0.97±0.11 cm) and the LV myocardial mass index (from 123.3±19.3 to 110.8±20.8 g/m2). At the end of follow-up end-systolic elastance significantly (p<0.001) decreased from 4.01±1.12 to 3.46±0.88 mm Hg/ml. In the subgroup of patients with reduced (in absolute value) LV longitudinal 2D-strain (n=27) at baseline, there was a significantly (p=0.005) increasing in this parameter at the end of the study (from -16.14±2.21% to -17.30±2.13%, Δ%=8.45±13.35).Conclusion. In naive patients 40-65 years old with stage II grade 1-2 EAH AHT with A/V SPC provides effective 24 hours BP control, significantly reduced LVH and improves LV strain parameters, which indicates decreasing of LV myocardial stiffness.

Oxidative imbalance and kidney damage in spontaneously hypertensive rats: activation of extrinsic apoptotic pathways

In both humans and animals, essential hypertension acts as a risk factor for subclinical kidney damage and precedes renal dysfunction. Several lines of evidence indicate that hypertension and oxidative stress are closely related. The increase in vascular oxidative stress plays a key role in the pathophysiological consequences of hypertension, including kidney disease. Our study examined this issue in spontaneously hypertensive rat (SHR), a reliable model of essential hypertension. We used SHR 20 weeks old when hypertension is stably developed, vascular remodeling started, but kidney function is preserved. We examined plasmatic pro-oxidant and antioxidant status showing a significant alteration in oxidative balance in SHR. As index of oxidative damage, we evaluated lipid peroxidation in kidney, liver, and skeletal muscle, detecting a significant rise in lipid peroxidation levels in all SHR tissues, particularly relevant in kidney. In addition, we analyzed the expression of cytoplasmic antioxidant enzymes, superoxide dismutase 1 (SOD1) and glutatione S-tranferasi P1 (GSTP1). In SHR liver, SOD1 expression slight increased while we have not detected any variation in other tissues. Concerning GSTP1, SHR renal tissues did not display variations in enzyme expression, while in the other tissues, we observed a significant increase in both monomeric and pro-apoptotic dimeric form of the enzyme. By analyzing apoptotic signal, we founded c-Jun N-terminal kinase (JNK) activation in all SHR tissues, but only kidney presented extrinsic apoptotic pathway activation. Our results suggest that, in hypertensive animals with preserved renal function, despite the remarkable oxidative damage of renal tissues, only the extrinsic apoptotic pathway is activated.

Toll-like receptor 4 mediates vascular remodeling in hyperhomocysteinemia

Although hyperhomocysteinemia (HHcy) is known to promote downstream pro-inflammatory cytokine elevation, the precise mechanism is still unknown. One of the possible receptors that could have significant attention in the field of hypertension is toll-like receptor 4 (TLR-4). TLR-4 is a cellular membrane protein that is ubiquitously expressed in all cell types of the vasculature. Its mutation can attenuate the effects of HHcy-mediated vascular inflammation and mitochondria- dependent cell death that suppresses hypertension. In this review, we observed that HHcy induces vascular remodeling through immunological adaptation, promoting inflammatory cytokine up-regulation (IL-1β, IL-6, TNF-α) and initiation of mitochondrial dysfunction leading to cell death and chronic vascular inflammation. The literature suggests that HHcy promotes TLR-4-driven chronic vascular inflammation and mitochondria-mediated cell death inducing peripheral vascular remodeling. In the previous studies, we have characterized the role of TLR-4 mutation in attenuating vascular remodeling in hyperhomocysteinemia. This review includes, but is not limited to, the physiological synergistic aspects of the downstream elevation of cytokines found within the vascular inflammatory cascade. These events subsequently induce mitochondrial dysfunction defined by excessive mitochondrial fission and mitochondrial apoptosis contributing to vascular remodeling followed by hypertension.

Antioxidant and antiapoptotic effects of sea cucumber and valsartan against doxorubicin-induced cardiotoxicity in rats: The role of low dose gamma irradiation

Doxorubicin (DOX) is a highly effective antineoplastic drug; however, the clinical use of DOX is limited by its dose dependent cardiotoxicity. This study was conducted to evaluate the cardioprotective effect of sea cucumber and valsartan against DOX-induced cardiotoxicity in rats. Also, the role of exposure to low dose γ radiation (LDR) on each of them was investigated, since LDR could suppress various reactive oxygen species-related diseases. Rats received DOX (2.5mg/kg, ip) in six equal injections over a period of 2weeks, sea cucumber (14.4mg/kg, p.o) and valsartan (30mg/kg, p.o) for 8 successive weeks. Exposure to LDR (0.5Gy) was performed one day prior to DOX. Results revealed that DOX administration elevated serum levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK-MB) and troponin-I as well as increased cardiac lipid peroxide content and myeloperoxidase (MPO) activity. Additionally, it increased cardiac expressions of iNOS and caspase-3, accompanied by reduction in cardiac total protein and glutathione (GSH) contents. Treatment with sea cucumber or valsartan improved the cardiotoxicity of DOX. Their adjuvant therapy with LDR offers an additional benefit to the cardioprotection of the therapeutic drugs. These results confirmed by histopathological examination. In conclusion, sea cucumber and valsartan alone or combined with LDR attenuated DOX-induced cardiotoxicity via their antioxidant and anti-apoptotic activities and thus might be useful in the treatment of human patients under doxorubicin chemotherapy.

Toll-like receptor 4 mutation suppresses hyperhomocysteinemia-induced hypertension

Hyperhomocysteinemia (HHcy) has been observed to promote hypertension, but the mechanisms are unclear. Toll-like receptor 4 (TLR-4) is a cellular membrane protein that is ubiquitously expressed in all cell types of the vasculature. TLR-4 activation has been known to promote inflammation that has been associated with the pathogenesis of hypertension. In this study we hypothesize that HHcy induces hypertension by TLR-4 activation, which promotes inflammatory cytokine (IL-1β, IL-6, and TNF-α) upregulation and initiation of mitochondria-dependent apoptosis, leading to cell death and chronic vascular inflammation. To test this hypothesis, we used C57BL/6J (WT) mice, cystathionine β-synthase (CBS)-deficient (CBS^+/-) mice with genetic mild HHcy, C3H/HeJ (C3H) mice with TLR-4 mutation, and mice with combined genetic HHcy and TLR-4 mutation (CBS^+/-/C3H). Ultrasonography of the superior mesenteric artery (SMA) detected an increase in wall-to-lumen ratio, resistive index (RI), and pulsatility index (PI). Tail cuff blood pressure (BP) measurement revealed elevated BP in CBS^+/- mice. RI, PI, and wall-to-lumen ratio of the SMA in CBS^+/-/C3H mice were similar to the control group, and BP was significantly alleviated. TLR-4, IL-1β, IL-6, and TNF-α expression were upregulated in the SMA of CBS^+/- mice and reduced in the SMA of CBS^+/-/C3H mice. Molecules involved in the mitochondria-mediated cell death pathway (BAX, caspase-9, and caspase-3) were upregulated in CBS^+/- mice and attenuated in CBS^+/-/C3H mice. We conclude that HHcy promotes TLR-4-driven chronic vascular inflammation and mitochondria-mediated cell death, inducing hypertension. TLR-4 mutation attenuates vascular inflammation and cell death, which suppress hypertension.

Triptolide induces the cell apoptosis of osteosarcoma cells through the TRAIL pathway

Research on triptolide, a diterpenoid epoxide found in the Thunder God Vine Tripterygium wilfordii, has increased our knowledge of the pharmacology, pharmacokinetics, toxicology and clinical application of this agent. In the present study, we aimed to identify the effects of triptolide on the apoptosis of osteosarcoma cells and to evaluate the anti-proliferative action of this agent. MG-63 cells were treated either with various doses of triptolide (50, 100 or 200 nM) or DMSO for 6, 12 and 24 h. Treatment with triptolide effectively suppressed the cell viability and induced the apoptosis of osteosarcoma MG-63 cells as detected by MTT assay and flow cytometry, respectively. In addition, by using caspase-3, caspase-8 and caspase-9 activity assays and western blot analysis, the anticancer effects of triptolide against osteosarcoma growth were found to involve activation of the DR-5/p53/Bax/caspase-9/ caspase-3 signaling pathway and the DR-5/FADD/caspase-8/lysosomal/cathepsin B/caspase-3 signaling pathway in the MG-63 cells. An important factor in the anticancer effects of triptolide against osteosarcoma was TRAIL-DR-5. The data suggest that triptolide may be a potential novel chemotherapeutic agent for osteosarcoma and acts through the TRAIL-DR-5 signaling pathway.

Impact of X-linked inhibitor of apoptosis protein on survival of nasopharyngeal carcinoma patients following radiotherapy

This study aims to investigate CNE1 and CNE2 cell proliferation and apoptosis of nasopharyngeal cancer (NPC) and X-linked inhibitor of apoptosis protein (XIAP) expression in NPC patients after radiotherapy. Quantitative real-time quantitative polymerase chain reaction (qRT-PCR) and Western Blot detected XIAP and XIAP-associated factor1 (XAF1) messenger RNA (mRNA) and protein expression of CNE1 and CNE2 in NPC cells irradiated by γ-ray; MTT and flow cytometry assays detected CNE2 cells proliferation and apoptotic rate, respectively. With a retrospective analysis of 109 NPC patients in Xinxiang Central Hospital, immunohistochemistry (IHC) method detected XIAP expression, followed by a 5-year clinical analysis of the prognosis relevance after radiotherapy. In vitro, the inhibition and apoptotic rates of cells increased with the growth of radiation dose. qRT-PCR and Western blot detection declared that XIAP mRNA and protein expression increased, whereas XAF1 mRNA and protein expression decreased with the growth of radiation dose and exposure time. And XIAP mRNA and protein expression were negatively correlated with proliferation and apoptotic rates of the cells. In vivo, positive XIAP expression rate was negatively correlated with pathological tumor-node-metastasis (p-TNM) staging and tumor differentiation. Further, high XIAP expression, high p-TNM staging, and lower degree of differentiation were significantly correlated with the decrease of NPC patients' survival rate. Additionally, XIAP expression, p-TNM staging, and degrees of differentiation were independent risk factors for the survival of the NPC patients after radiotherapy. Increased XIAP expression and decreased XAF1 expression may be one reason for the apoptosis delays of CNE1 and CNE2 cells after irradiation, and the XIAP expression or the p-TNM staging and degree of differentiation are independent risk factors for NPC patients' survival after radiotherapy, providing a molecular rationale for radiotherapy and prognosis of NPC.

Clinical management of dilated cardiomyopathy: current knowledge and future perspectives

Dilated cardiomyopathy (DCM) is a primary heart muscle disease characterized by a progressive dilation and dysfunction of either the left or both ventricles. The management of DCM is currently challenging for clinicians. The persistent lack of knowledge about the etiology and pathophysiology of this disease continues to determine important fields of uncertainty in managing this condition. Molecular cardiology and genetics currently represent the most crucial horizon of increasing knowledge. Understanding the mechanisms underlying the disease allows clinicians to treat this disease more effectively and to further improve outcomes of DCM patients through advancements in etiologic characterization, prognostic stratification and individualized therapy. Left ventricular reverse remodeling predicts a lower rate of major cardiac adverse events independently from other factors. Optimized medical treatment and device implantation are pivotal in inducing left ventricular reverse remodeling. Newly identified targets, such as angiotensin-neprilysin inhibition, phosphodiesterase inhibition and calcium sensitizing are important in improving prognosis in patients affected by DCM.