Protective effect of guggulsterone against cardiomyocyte injury induced by doxorubicin in vitro

Protective effects of protocatechuic acid against doxorubicin- and arsenic trioxide-induced toxicity in cardiomyocytes

Background and purpose

Some chemotherapeutic drugs are associated with an increased risk of cardiotoxicity in patients. Protocatechuic acid (PCA) is a phenolic acid with valuable cardiovascular, chemo-preventive, and anticancer activities. Recent studies have shown the cardioprotective effects of PCA in several pathological conditions. This investigation aimed to assess the possible protective effects of PCA on cardiomyocytes against toxicities caused by anti-neoplastic agents, doxorubicin (DOX), and arsenic trioxide (ATO).

Experimental approach

H9C2 cells were exposed to DOX (1 μM) or ATO (35 μM) after 24 h pretreatment with PCA (1-100 μM). MTT and lactate dehydrogenase (LDH) tests were used to define cell viability or cytotoxicity. Total oxidant and antioxidant capacities were evaluated by measuring hydroperoxides and ferric-reducing antioxidant power (FRAP) levels. Expression of the TLR4 gene was also quantitatively estimated by real-time polymerase chain reaction.

Findings/Results

PCA showed a proliferative effect on cardiomyocytes and significantly enhanced cell viability and reduced cytotoxicity of DOX and ATO during MTT and LDH assays. Pretreatment of cardiomyocytes with PCA significantly decreased hydroperoxide levels and elevated FRAP value. Moreover, PCA meaningfully decreased TLR4 expression in DOX-and ATO-treated cardiomyocytes.

Conclusions and implications

In conclusion, antioxidant and cytoprotective activities were found for PCA versus toxicities caused by DOX and ATO in cardiomyocytes. However, further in vivo investigations are recommended to assess its clinical value for the prevention and treatment of cardiotoxicity induced by chemotherapeutic agents.

Z-Guggulsterone alleviated oxidative stress and inflammation through inhibiting the TXNIP/NLRP3 axis in ischemic stroke

Ischemic stroke is a serious and life-threatening cerebrovascular thrombotic disease; however, the therapeutic strategy is limited for the complicated mechanism and narrow therapeutic window. Our previous study suggested that Z-Guggulsterone (Z-GS), an active component derived from myrrh, is a good candidate for cerebral injury. The object of this study is to investigate the exact mechanisms of Z-GS in cerebral ischemic stroke. Rats were used to conduct middle cerebral artery occlusion (MCAO) model and were treated with different dosage of Z-GS. Morphological results showed that Z-GS significantly alleviated neurological deficits, infarct volume and histopathological damage in MCAO rats. A total of 8276 differentially expressed genes were identified based on microarray analysis. Oxidation-reduction process and inflammatory response were enriched as the significant gene ontology items. TXNIP and NLRP3 were screened as the potential target genes by Series Test of Cluster (STC) analysis. The results were validated by immunohistochemistry and immunofluorescence staining. Besides, Z-GS successfully inhibited oxidative stress and inflammatory response in oxygen-glucose deprivation (OGD) treated neurons. Knockdown of TXNIP significantly decreased the expression of NLRP3 in OGD-induced neurons. In addition, Z-GS treatment scarcely changed the expressions of NLRP3 in siRNA-TXNIP pretreated cells compared with the siRNA-TXNIP alone treatment group, suggesting that the neuroprotective effect of Z-GS was dependent on TXNIP-NLRP3 axis. Taken together, this study revealed that Z-GS exerted neuroprotective property through alleviated oxidative stress and inflammation via inhibiting the TXNIP/NLRP3 axis. Z-GS could be considered as a promising candidate for the treatment of ischemic stroke.

Therapeutic Effect of Guggulsterone in Primary Cultured Orbital Fibroblasts Obtained From Patients with Graves' Orbitopathy

Purpose

Inflammation, hyaluronan production, and adipogenesis are the main pathological events leading to Graves' orbitopathy (GO). Guggulsterone (GS), a phytosterol found in the resin of the guggul plant, is a well-known treatment for several inflammatory disorders, such as arthritis, obesity, and hyperlipidemia. Here we investigated the effects of GS treatment on GO pathology.

Methods

Using primary cultures of orbital fibroblasts from GO patients and non-GO controls, we examined the effects of GS on hyaluronan production and the production of proinflammatory cytokines induced by interleukin (IL)-1β, using real-time reverse transcription-polymerase chain reaction analysis, western blots, and enzyme-linked immunosorbent assays. Further, adipogenic differentiation was evaluated by quantification of Oil Red O staining and assessment of protein levels of peroxisome proliferator activator gamma (PPARγ), CCAAT-enhancer-binding proteins (C/EBP) α and β, and sterol regulatory element-binding protein-1 (SREBP-1).

Results

Treatment with noncytotoxic concentrations of GS resulted in the dose-dependent inhibition of IL-1β-induced inflammatory cytokines, including IL-6, IL-8, MCP-1, and COX-2, at both mRNA and protein levels. The hyaluronan level was also significantly suppressed by GS. Moreover, GS significantly decreased the formation of lipid droplets and expression of PPARγ, C/EBP α/β, and SREBP-1 in a dose-dependent manner. GS pretreatment attenuated the phosphorylation of nuclear factor-kappa B induced by IL-1β.

Conclusions

Our data show significant inhibitory effects of GS on inflammation, production of hyaluronan, and adipogenesis in orbital fibroblasts. To our knowledge, this is the first in vitro preclinical evidence of the therapeutic effect of GS in GO.

The Oleo-Gum-Resin of Commiphora myrrha Ameliorates Male Reproductive Dysfunctions in Streptozotocin-Induced Hyperglycemic Rats

Background: The oleo-gum-resin of Commiphora myrrha (myrrh) has a long history of therapeutic use in traditional medicine. The aim of this study was to seek for the scientific evidence to determine whether the ethanolic extract of myrrh (EEM) has any beneficial effects on Streptozotocin (STZ) induced testicular impairments, and explore the possible mechanisms underlying such actions. Methods: Forty-eight severe and complicated diabetic rats (fasting blood glucose above 350 mg/dL), randomly were divided into six equal groups (n=8). Besides, eight healthy rats allocated as a normal control group and only treated with vehicle solution. The diabetic animals orally received the extract (100, 200, 300, and 500 mg/kg), metformin (500 mg/kg) or vehicle solution for 28 days. As a final point, plasma glucose and insulin, circulatory sex hormones, sperm parameters including sperm concentration, motility and viability and also testicular malondialdehyde (MDA) levels were assessed. Furthermore, quantitative histological evaluation of seminiferous tubules area and determination of germinal cells apoptosis were performed. Results: None of the studied doses of EEM showed anti-diabetic effects. However, the extract mainly at the maximum dose (500 mg/kg) exhibited beneficial effects on reproductive impairments. The EEM treated rats mainly at 500 mg/kg had significantly higher sperm concentration, sperm motility, sperm viability, sex hormones and lower testicular MDA and germ cell apoptosis index than untreated diabetic rats. Conclusion: These results indicated that EEM may have beneficial effects against reproductive dysfunction induced by diabetes. The mechanisms behind the effects might be associated with the EEM sex hormone booster potential, antioxidant and anti-apoptotic properties.

Googling the Guggul (Commiphora and Boswellia) for Prevention of Chronic Diseases

Extensive research during last 2 decades has revealed that most drugs discovered today, although costs billions of dollars for discovery, and yet they are highly ineffective in their clinical response. For instance, the European Medicines Agency has approved 68 anti-cancer drugs, and out of which 39 has reached the market level with no indication of increased survival nor betterment of quality of life. Even when drugs did improve survival rate compared to available treatment strategies, most of these were found to be clinically insignificant. This is a fundamental problem with modern drug discovery which is based on thinking that most chronic diseases are caused by alteration of a single gene and thus most therapies are single gene-targeted therapies. However, extensive research has revealed that most chronic diseases are caused by multiple gene products. Although most drugs designed by man are mono-targeted therapies, however, those designed by "mother nature" and have been used for thousands of years, are "multi-targeted" therapies. In this review, we examine two agents that have been around for thousands of years, namely "guggul" from Commiphora and Boswellia. Although we are all familiar with the search engine "google," this is another type of "guggul" that has been used for centuries and being explored for its various biological activities. The current review summarizes the traditional uses, chemistry, in vitro and in vivo biological activities, molecular targets, and clinical trials performed with these agents.

Anticancer effects of resveratrol in canine hemangiosarcoma cell lines

Hemangiosarcoma (HSA) is a highly malignant tumour with aggressive biological behaviour. HSAs are more common in dogs than other domestic animals. The median survival time of dogs with HSA remains short, even with chemotherapy and surgery. Therefore, there is a critical need to improve the adjuvant chemotherapeutic regimens to improve clinical outcomes in dogs with HSA. Resveratrol has been shown to possess strong anti-proliferative and/or pro-apoptotic properties in human cancer cell lines. Nevertheless, the potential anticancer effects of resveratrol have not been reported in canine HSAs. The objective of this study is to determine the growth inhibitory effects of resveratrol in HSA cells when used alone or in combination with doxorubicin, a commonly used chemotherapeutic agent. Frog and DD-1 canine HSA cell lines were treated with varying concentrations of resveratrol with and without doxorubicin. Cell viability was measured by the MTT assay. The expression of apoptotic proteins, activation of p38 mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were assessed by western blotting. Similar to human cancer cell lines, resveratrol markedly inhibited the growth and induced apoptosis in both HSA cell lines. Mechanistically, resveratrol activated p38 MAPK, but did not affect the AMPK or the ERK1/2 pathways. Additional experiments showed that resveratrol augmented the growth-inhibitory and apoptotic effects of doxorubicin in both HSA cell lines. These findings suggest that resveratrol has pro-apoptotic effects in canine HSA cells; therefore, its use as a potential adjunct therapy in canine HSA patients warrants further investigation.

Cardioprotective mechanisms of phytochemicals against doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an anthracycline antibiotic, which is effectively used in the treatment of different malignancies, such as leukemias and lymphomas. Its most serious side effect is dose-dependent cardiotoxicity, which occurs through inducing oxidative stress apoptosis. Due to the myelosuppressive effect of dexrazoxane, a commonly-used drug to alleviate DOX-induced cardiotoxicity, researchers investigated the potential of phytochemicals for prophylaxis and treatment of this condition. Phytochemicals are plant chemicals that have protective or disease preventive properties. Preclinical trials have shown antioxidant properties for several plant extracts, such as those of Aerva lanata, Aronia melanocarpa, Astragalus polysaccharide, and Bombyx mori plants. Other plant extracts showed an ability to inhibit apoptosis, such as those of Astragalus polysaccharide, Azadirachta indica, Bombyx mori, and Allium stavium plants. Unlike synthetic agents, phytochemicals do not impair the clinical activity of DOX and they are particularly safe for long-term use. In this review, we summarized the results of preclinical trials that investigated the cardioprotective effects of phytochemicals against DOX-induced cardiotoxicity. Future human trials are required to translate these cardioprotective mechanisms into practical clinical implications.

Anti-inflammatory effects of guggulsterone on murine macrophage by inhibiting LPS-induced inflammatory cytokines in NF-κB signaling pathway

The present study was aimed to investigate the effects of guggulsterone (GS) on proinflammatory responses as well as the underlying molecular mechanisms in macrophage upon lipopolysaccharide (LPS) stimulation. Effects of GS on viability of Raw264.7 cells were examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Real-time polymerase chain reaction (PCR) was employed to examine the mRNA expression of cytokines, including interleukin 1β (IL-1β), tumor necrosis factor-alpha (TNF-α), and inducible nitric oxide synthase (iNOS). Phosphorylations of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (p38), and inhibitor of nuclear factor kappaB (IκB) were determined using immunoblotting. The results revealed that GS was not toxic to Raw264.7 cells at designated concentrations. We demonstrated that GS significantly suppressed the elevated mRNA expression of proinflammatory cytokines, including IL-1β, TNF-α, and iNOS in a dose-dependent manner. GS treatment reduced the level of IκB phosphorylation in LPS-stimulated macrophages in a dose-dependent manner. Use of BAY 11-7082, an inhibitor of nuclear factor-kappaB (NF-κB), led to significantly suppressing effects on IL-1β and TNF-α expression similar as that of GS-treated cells. Our findings suggest that GS possesses anti-inflammatory activity, which may be attributed to downregulation of iNOS and inhibition of NF-κB activity in LPS-stimulated Raw264.7 cells.

Cardioprotective Potentials of Plant-Derived Small Molecules against Doxorubicin Associated Cardiotoxicity

Doxorubicin (DOX) is a potent and widely used anthracycline antibiotic for the treatment of several malignancies. Unfortunately, the clinical utility of DOX is often restricted due to the elicitation of organ toxicity. Particularly, the increased risk for the development of dilated cardiomyopathy by DOX among the cancer survivors warrants major attention from the physicians as well as researchers to develop adjuvant agents to neutralize the noxious effects of DOX on the healthy myocardium. Despite these pitfalls, the use of traditional cytotoxic drugs continues to be the mainstay treatment for several types of cancer. Recently, phytochemicals have gained attention for their anticancer, chemopreventive, and cardioprotective activities. The ideal cardioprotective agents should not compromise the clinical efficacy of DOX and should be devoid of cumulative or irreversible toxicity on the naïve tissues. Furthermore, adjuvants possessing synergistic anticancer activity and quelling of chemoresistance would significantly enhance the clinical utility in combating DOX-induced cardiotoxicity. The present review renders an overview of cardioprotective effects of plant-derived small molecules and their purported mechanisms against DOX-induced cardiotoxicity. Phytochemicals serve as the reservoirs of pharmacophore which can be utilized as templates for developing safe and potential novel cardioprotective agents in combating DOX-induced cardiotoxicity.

A New Ionone Glycoside and Three New Rhemaneolignans from the Roots of Rehmannia glutinosa

A new ionone glycoside, frehmaglutoside I (1), and three new rhemaneolignans A-C (2-4) were isolated from the 95% EtOH extract of the roots of Rehmannia glutinosa. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI-MS, 1D and 2D NMR) analyses. In addition, these compounds were evaluated for their protective effects on cardiocytes impaired by doxorubicin in H9c2 cells. Among them, compounds 1-3 exhibited protective effects against DOX-induced cardiotoxicity.

Synergistic protective role of mirazid (Commiphora molmol) and ascorbic acid against tilmicosin-induced cardiotoxicity in mice

Tilmicosin (TIL) is a long-acting macrolide antibiotic approved for the treatment of cattle with Bovine Respiratory Disease. However, overdose of TIL has been reported to induce cardiotoxicity. The purpose of our experiment was to evaluate the protective effects of Commiphora molmol (mirazid (MRZ); myrrh) and (or) ascorbic acid (AA) against TIL-induced cardiotoxicity in mice. MRZ and AA were orally administered using stomach gavage, either alone or in combination for 5 consecutive days, followed with a single TIL overdose. TIL overdose induced a significant increase in serum levels of cardiac damage biomarkers (AST, LDH, CK, CK-MB, and cTnT), as well as cardiac lipid peroxidation, but cardiac levels of antioxidant biomarkers (GSH, SOD, CAT, and TAC) were decreased. Both MRZ and AA tended to normalize the elevated serum levels of cardiac injury biomarkers. Furthermore, MRZ and AA reduced TIL-induced lipid peroxidation and oxidative stress parameters. MRZ and AA combined produced a synergistic cardioprotective effect. We conclude that myrrh and (or) vitamin C administration minimizes the toxic effects of TIL through their free-radical-scavenging and potent antioxidant activities.

pH-responsive hydrogels with dispersed hydrophobic nanoparticles for the oral delivery of chemotherapeutics

Amphiphilic polymer carriers were formed by polymerizing a hydrophilic, pH-responsive hydrogel composed of poly(methacrylic-grafted-ethylene glycol) (P(MAA-g-EG)) in the presence of hydrophobic PMMA nanoparticles. These polymer carriers were varied in PMMA nanoparticle content to elicit a variety of physiochemical properties which would preferentially load doxorubicin, a hydrophobic chemotherapeutic, and release doxorubicin locally in the colon for the treatment of colon cancers. Loading levels ranged from 49% to 64% and increased with increasing nanoparticle content. Doxorubicin loaded polymers were released in a physiological model where low pH was used to simulate the stomach and then stepped to more neutral conditions to simulate the upper small intestine. P(MAA-g-EG) containing nanoparticles were less mucoadhesive as determined using a tensile tester, polymer samples, and fresh porcine small intestine. The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were noncytotoxic at varying concentrations and exposure times.