Aspalathin Reverts Doxorubicin-Induced Cardiotoxicity through Increased Autophagy and Decreased Expression of p53/mTOR/p62 Signaling

Antioxidants activities of phytochemicals perspective modulation of autophagy and apoptosis to treating cancer

The study of chemicals extracted from natural sources should be encouraged due to the significant number of cancer deaths each year and the financial burden imposed by this disease on society. The causes of almost all cancers involve a combination of lifestyle, environmental factors, and genetic and inherited factors. Modern medicine researchers are increasingly interested in traditional phytochemicals as they hold potential for new bioactive compounds with medical applications. Recent publications have provided evidence of the antitumor properties of phytochemicals, a key component of traditional Chinese medicine, thereby opening new avenues for their use in modern medicine. Various studies have demonstrated a strong correlation between apoptosis and autophagy, two critical mechanisms involved in cancer formation and regulation, indicating diverse forms of crosstalk between them. Phytochemicals have the ability to activate both pro-apoptotic and pro-autophagic pathways. Therefore, understanding how phytochemicals influence the relationship between apoptosis and autophagy is crucial for developing a new cancer treatment strategy that targets these molecular mechanisms. This review aims to explore natural phytochemicals that have demonstrated anticancer effects, focusing on their role in regulating the crosstalk between apoptosis and autophagy, which contributes to uncontrolled tumor cell growth. Additionally, the review highlights the limitations and challenges of current research methodologies while suggesting potential avenues for future research in this field.

The Role of mTOR in Doxorubicin-Altered Cardiac Metabolism: A Promising Therapeutic Target of Natural Compounds

Doxorubicin (DOX) is commonly used for the treatment of various types of cancer, however can cause serious side effects, including cardiotoxicity. The mechanisms involved in DOX-induced cardiac damage are complex and not yet fully understood. One mechanism is the disruption of cardiac metabolism, which can impair cardiac function. The mammalian target of rapamycin (mTOR) is a key regulator of cardiac energy metabolism, and dysregulation of mTOR signaling has been implicated in DOX-induced cardiac dysfunction. Natural compounds (NCs) have been shown to improve cardiac function in vivo and in vitro models of DOX-induced cardiotoxicity. This review article explores the protective effects of NCs against DOX-induced cardiac injury, with a focus on their regulation of mTOR signaling pathways. Generally, the modulation of mTOR signaling by NCs represents a promising strategy for decreasing the cardiotoxic effects of DOX.

A review on the impact of TRAIL on cancer signaling and targeting via phytochemicals for possible cancer therapy

Anticancer therapies have been the continual pursuit of this age. Cancer has been ravaging all across the globe breathing not just threats but demonstrating them. Remedies for cancer have been frantically sought after. Few have worked out, yet till date, the available cancer therapies have not delivered a holistic solution. In a world where the search for therapies is levitating towards natural remedies, solutions based on phytochemicals are highly prospective attractions. A lot has been achieved with inputs from plant resources, providing numerous natural remedies. In the current review, we intensely survey the progress achieved in the treatment of cancer through phytochemicals-based programmed cell death of cancer cells. More specifically, we have further reviewed and discussed the role of phytochemicals in activating apoptosis via Tumor Necrosis Factor-Alpha-Related Apoptosis-Inducing Ligand (TRAIL), which is a cell protein that can attach to certain molecules in cancer cells, killing cancer cells. The objective of this review is to enlist the various phytochemicals that are available for specifically contributing towards triggering the TRAIL cell protein-mediated cancer therapy and to point out the research gaps that require future research motivation. This is the first review of this kind in this research direction.

Pharmacological activity of Aspalathus linearis extracts: pre-clinical research in view of prospective neuroprotection

OBJECTIVES

Rooibos tea, a very popular everyday beverage made of Aspalathus linearis plant material and containing multiple polyphenolic compounds, reveals an expectation to positively affect various processes observed in the pathogenesis of neurodegenerative diseases as in the case of consumption of other polyphenol-abundant food products.

METHODS

This review is based on available data from pre-clinical in vitro and in vivo studies and presents a broad report on the pharmacological activity of the A. linearis extracts relevant for neurodegenerative diseases.

RESULTS

Flavonoids present in herbal infusions are absorbed from gastro-intestinal tract and may affect the central nervous system. The experimental investigations yield the results indicating to supporting role of A. linearis in the prevention of neurodegeneration, primarily owing to anti-oxidative and anti-inflammatory properties, anti-hyperglycaemic and anti-hyperlipidaemic effects as well as favourable impact on neurotransmission with following cognitive and behavioural after-math.

DISCUSSION

The multiple pharmacological activities and safety of Aspalathus linearis extracts are commented in the manuscript. The continuous rooibos tea consumption seems to be safe (despite anecdotal liver irritation); however, there is a risk of herbal-drug interactions.

Hydropersulfides (RSSH) attenuate doxorubicin-induced cardiotoxicity while boosting its anticancer action

Cardiotoxicity is a frequent and often lethal complication of doxorubicin (DOX)-based chemotherapy. Here, we report that hydropersulfides (RSSH) are the most effective reactive sulfur species in conferring protection against DOX-induced toxicity in H9c2 cardiac cells. Mechanistically, RSSH supplementation alleviates the DOX-evoked surge in reactive oxygen species (ROS), activating nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent pathways, thus boosting endogenous antioxidant defenses. Simultaneously, RSSH turns on peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), a master regulator of mitochondrial function, while decreasing caspase-3 activity to inhibit apoptosis. Of note, we find that RSSH potentiate anticancer DOX effects in three different cancer cell lines, with evidence that suggests this occurs via induction of reductive stress. Indeed, cancer cells already exhibit much higher basal hydrogen sulfide (H2S), sulfane sulfur, and reducing equivalents compared to cardiac cells. Thus, RSSH may represent a new promising avenue to fend off DOX-induced cardiotoxicity while boosting its anticancer effects.

MST1: A future novel target for cardiac diseases

Major heart diseases pose a serious threat to human health. Finding early diagnostic markers and key therapeutic targets is an urgent scientific problem in this field. Mammalian sterile 20-like kinase 1 (MST1) is a protein kinase, and the occurrence of many heart diseases is related to the continuous activation of the MST1 gene. With the deepening of the research, the potential role of MST1 in promoting the development of heart disease has become more apparent. Therefore, to better understand the role of MST1 in the pathogenesis of heart disease, this work systematically summarizes the role of MST1 in the pathogenesis of heart disease, gives a comprehensive overview of its possible strategies in the diagnosis and treatment of heart disease, and analyzes its potential significance as a marker for the diagnosis and treatment of heart disease.

Aspalathin alleviates skeletal muscle insulin resistance and mitochondrial dysfunction

Natural compounds may bear promising therapeutic benefits against metabolic diseases such as type 2 diabetes mellitus (T2DM), which are characterized by a state of insulin resistance and mitochondrial dysfunction. Here, we examined the cellular mechanisms by which aspalathin, a dihydrochalcone C-glucoside unique to rooibos, may ameliorate palmitate-induced insulin resistance and mitochondrial dysfunction in cultured C2C12 myotubules. This current study demonstrated that aspalathin remains effective in improving glucose uptake in insulin-resistant skeletal muscle cells, supported by the upregulation of insulin-dependent signaling that involves the activation of insulin receptor (IR) and direct phosphorylation of protein kinase B (AKT). Interestingly, aspalathin also improved mitochondrial respiration and function, which was evident by an increased expression of carnitine palmitoyltransferase 1 (Cpt1), fatty acid transport protein 1 (Fatp1), sirtuin 1 (Sirt1), nuclear respiratory factor 1 (Nrf1), and transcription factor A, mitochondrial (Tfam). Importantly, our results showed that aspalathin treatment was effective in ameliorating the devastating outcomes of insulin resistance and mitochondrial dysfunction that are linked with an undesired pro-inflammatory response, by reducing the levels of well-known pro-inflammatory markers such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and protein kinase C-theta (PKC-theta). Thus, beyond improving glucose uptake and insulin signaling, the current study brings a new perspective in the therapeutic benefits of aspalathin in improving mitochondrial respiration and blocking inflammation to attenuate the detrimental effect of palmitate in skeletal muscle cells.

Prevention of Anthracycline-Induced Cardiotoxicity: The Good and Bad of Current and Alternative Therapies

Doxorubicin (Dox)-induced cardiotoxicity (DIC) remains a serious health burden, especially in developing countries. Unfortunately, the high cost of current preventative strategies has marginalized numerous cancer patients because of socio-economic factors. In addition, the efficacy of these strategies, without reducing the chemotherapeutic properties of Dox, is frequently questioned. These limitations have widened the gap and necessity for alternative medicines, like flavonoids, to be investigated. However, new therapeutics may also present their own shortcomings, ruling out the idea of “natural is safe”. The U.S. Food and Drug Administration (FDA) has stipulated that the concept of drug-safety be considered in all pre-clinical and clinical studies, to explore the pharmacokinetics and potential interactions of the drugs being investigated. As such our studies on flavonoids, as cardio-protectants against DIC, have been centered around cardiac and cancer models, to ensure that the efficacy of Dox is preserved. Our findings thus far suggest that flavonoids of Galenia africana could be suitable candidates for the prevention of DIC. However, this still requires further investigation, which would focus on drug-interactions as well as in vivo experimental models to determine the extent of cardioprotection.

Saponins and their derivatives: Potential candidates to alleviate anthracycline-induced cardiotoxicity and multidrug resistance

Anthracyclines (ANTs) continue to play an irreplaceable role in oncology treatment. However, the clinical application of ANTs has been limited. In the first place, ANTs can cause dose-dependent cardiotoxicity such as arrhythmia, cardiomyopathy, and congestive heart failure. In the second place, the development of multidrug resistance (MDR) leads to their chemotherapeutic failure. Oncology cardiologists are urgently searching for agents that can both protect the heart and reverse MDR without compromising the antitumor effects of ANTs. Based on in vivo and in vitro data, we found that natural compounds, including saponins, may be active agents for other both natural and chemical compounds in the inhibition of anthracycline-induced cardiotoxicity (AIC) and the reversal of MDR. In this review, we summarize the work of previous researchers, describe the mechanisms of AIC and MDR, and focus on revealing the pharmacological effects and potential molecular targets of saponins and their derivatives in the inhibition of AIC and the reversal of MDR, aiming to encourage future research and clinical trials.

Molecular insights into the pathophysiology of doxorubicin-induced cardiotoxicity: a graphical representation

A breakthrough in oncology research was the discovery of doxorubicin (Dox) in the 1960's. Unlike other chemotherapy drugs, Dox was determined to have a greater therapeutic index. Since its discovery, Dox has, in part, contributed to the 5-10-year survival increase in cancer patient outcomes. Unfortunately, despite its efficacy, both in adult and pediatric cancers, the clinical significance of Dox is tainted by its adverse side effects, which usually manifest as cardiotoxicity. The issue stems from Dox's lack of specificity which prevents it from accurately distinguishing between cancer cells and healthy cell lines, like cardiomyocytes. In addition, the high binding affinity of Dox to topoisomerases, which are abundantly found in cancer and cardiac cells in different isoforms, potentiates DNA damage. In both cell lines, Dox induces cytotoxicity by stimulating the production of pro-oxidants whilst inhibiting antioxidant enzymatic activity. Given that the cardiac muscle has an inherently low antioxidant capacity makes it susceptible to oxidative damage thereby, allowing the accumulation of Dox within the myocardium. Subsequently, Dox drives the activation of cell death pathways, such as ferroptosis, necroptosis and apoptosis by triggering numerous cellular responses that have been implicated in diseases. To date, the exact mechanism by which Dox induces the cardiotoxicity remains an aspect of much interest in cardio-oncology research. Hence, the current review summarizes the proposed mechanisms that are associated with the onset and progression of DIC.

Nano-Resveratrol: A Promising Candidate for the Treatment of Renal Toxicity Induced by Doxorubicin in Rats Through Modulation of Beclin-1 and mTOR

Background: Although doxorubicin (DXR) is one of the most used anticancer drugs, it can cause life-threatening renal damage. There has been no effective treatment for DXR-induced renal damage until now.

Aim: This work aims at examining the potential impact of nano-resveratrol (N-Resv), native resveratrol (Resv), and their combination with carvedilol (Card) against DXR-induced renal toxicity in rats and to investigate the mechanisms through which these antioxidants act to ameliorate DXR nephrotoxicity. Method: DXR was administered to rats (2 mg/kg, i.p.) twice weekly over 5 weeks. The antioxidants in question were taken 1 week before the DXR dose for 6 weeks.

Results: DXR exhibited an elevation in serum urea, creatinine, renal lipid peroxide levels, endoglin expression, kidney injury molecule-1 (KIM-1), and beclin-1. On the other hand, renal podocin and mTOR expression and GSH levels were declined. In addition, DNA fragmentation was markedly increased in the DXR-administered group. Treatment with either Resv or N-Resv alone or in combination with Card ameliorated the previously measured parameters.

Conclusion: N-Resv showed superior effectiveness relative to Resv in most of the measured parameters. Histopathological examination revealed amelioration of renal structural and cellular changes after DXR by Card and N-Resv, thus validating the previous biochemical and molecular results.

The Multifaceted Role of Flavonoids in Cancer Therapy: Leveraging Autophagy with a Double-Edged Sword

Flavonoids are considered as pleiotropic, safe, and readily obtainable molecules. A large number of recent studies have proposed that flavonoids have potential in the treatment of tumors by the modulation of autophagy. In many cases, flavonoids suppress cancer by stimulating excessive autophagy or impairing autophagy flux especially in apoptosis-resistant cancer cells. However, the anti-cancer activity of flavonoids may be attenuated due to the simultaneous induction of protective autophagy. Notably, flavonoids-triggered protective autophagy is becoming a trend for preventing cancer in the clinical setting or for protecting patients from conventional therapeutic side effects in normal tissues. In this review, focusing on the underlying autophagic mechanisms of flavonoids, we hope to provide a new perspective for clinical application of flavonoids in cancer therapy. In addition, we highlight new research ideas for the development of new dosage forms of flavonoids to improve their various pharmacological effects, establishing flavonoids as ideal candidates for cancer prevention and therapy in the clinic.

Resveratrol significantly improves cell survival in comparison to dexrazoxane and carvedilol in a h9c2 model of doxorubicin induced cardiotoxicity

Cancer is one of the leading causes of deaths worldwide with 18.1 million deaths per year. Although there have been significant advances in anti-cancer therapies, they can often result in side effects with cardiovascular complications being the most severe. Dexrazoxane is the only currently approved treatment for prevention of anthracycline induced cardiotoxicity but there are concerns about its use due to the development of secondary malignancies and myelodysplastic syndrome. Additionally, it is only recommended in patients who are due to receive a total cumulative dose of 300 mg/m² of doxorubicin or 540 mg/m² of epirubicin. Thus, there exists an urgent need to develop new therapeutic strategies to counteract anthracycline induced cardiotoxicity. The h9c2 cardiomyoblast was investigated for its differentiation capacity and used to screen and compare promising prophylactics for doxorubicin induced cardiotoxicity. The half maximal inhibitory concentration of doxorubicin was determined in differentiated h9c2 cells after 24 h of exposure, to establish a model for drug screening. Cells were treated with dexrazoxane, resveratrol, and carvedilol either 3 h or 24 h prior to doxorubicin treatment. The ability of these cardioprotectants to prevent cardiotoxicity was analysed using the cck-8 cell viability assay and the dichlorofluorescin diacetate (DCFDA) reactive oxygen species (ROS) assay. There was no significant increase in survival in treatment groups after 3 h, however, at 24 h, resveratrol significantly improved survival compared to all other groups (p < 0.05). Additionally, dexrazoxane and resveratrol significantly decreased ROS formation at 3 h (p < 0.05) and all groups significantly decreased ROS production at 24 h (p < 0.001). This work is the first comparison of these cardioprotectants and suggests that resveratrol may be a more effective treatment in the prevention of anthracycline induced cardiotoxicity, compared to dexrazoxane and carvedilol. However, further work will be needed in order to decipher the exact mechanism and potential of this drug in the clinic.

Anti-ovarian cancer potential of phytocompound and extract from South African medicinal plants and their role in the development of chemotherapeutic agents

Ovarian cancer (OC) accounts for the highest tumor-related mortality among the gynecologic malignancies. Most of the OC patients diagnosed with advanced-stage (III and IV) this situation creates panic and provokes an emergency to discover a new therapeutic strategy. Plants that possess medicinal properties are gaining attention as they are enriched with various chemical compounds that are potential to treat various diseases. It is a prolonged process to provide innovative and significant leads against a range of pharmacological targets for a human disease management system. Though challenges and difficulties are faced in the development of a new drug, the emergence of combinatorial chemistry is providing a new ray of hope and also, the executed effort in discovering the drug, and a chemical compound has been remarkably successful. This review discussed the role of medicinal plants that are native of South Africa in treating the Ovarian Cancer and in drug discovery.

Phytochemicals as a Complement to Cancer Chemotherapy: Pharmacological Modulation of the Autophagy-Apoptosis Pathway

Bioactive plant derived compounds are important for a wide range of therapeutic applications, and some display promising anticancer properties. Further evidence suggests that phytochemicals modulate autophagy and apoptosis, the two crucial cellular pathways involved in the underlying pathobiology of cancer development and regulation. Pharmacological targeting of autophagy and apoptosis signaling using phytochemicals therefore offers a promising strategy that is complementary to conventional cancer chemotherapy. In this review, we sought to highlight the molecular basis of the autophagic-apoptotic pathway to understand its implication in the pathobiology of cancer, and explore this fundamental cellular process as a druggable anticancer target. We also aimed to present recent advances and address the limitations faced in the therapeutic development of phytochemical-based anticancer drugs.

Tioconazole and Chloroquine Act Synergistically to Combat Doxorubicin-Induced Toxicity via Inactivation of PI3K/AKT/mTOR Signaling Mediated ROS-Dependent Apoptosis and Autophagic Flux Inhibition in MCF-7 Breast Cancer Cells

Cancer is a complex devastating disease with enormous treatment challenges, including chemo- and radiotherapeutic resistance. Combination therapy demonstrated a promising strategy to target hard-to-treat cancers and sensitize cancer cells to conventional anti-cancer drugs such as doxorubicin. This study aimed to establish molecular profiling and therapeutic efficacy assessment of chloroquine and/or tioconazole (TIC) combination with doxorubicin (DOX) as anew combination model in MCF-7 breast cancer. The drugs are tested against apoptotic/autophagic pathways and related redox status. Molecular docking revealed that chloroquine (CQ) and TIC could be potential PI3K and ATG4B pathway inhibitors. Combination therapy significantly inhibited cancer cell viability, PI3K/AkT/mTOR pathway, and tumor-supporting autophagic flux, however, induced apoptotic pathways and altered nuclear genotoxic feature. Our data revealed that the combination cocktail therapy markedly inhibited tumor proliferation marker (KI-67) and cell growth, along with the accumulation of autophagosomes and elevation of LC3-II and p62 levels indicated autophagic flux blockage and increased apoptosis. Additionally, CQ and/or TIC combination therapy with DOX exerts its activity on the redox balance of cancer cells mediated ROS-dependent apoptosis induction achieved by GPX3 suppression. Besides, Autophagy inhibition causes moderately upregulation in ATGs 5,7 redundant proteins strengthened combinations induced apoptosis, whereas inhibition of PI3K/AKT/mTOR pathway with Beclin-1 upregulation leading to cytodestructive autophagy with overcome drug resistance effectively in curing cancer. Notably, the tumor growth inhibition and various antioxidant effects were observed in vivo. These results suggest CQ and/or TIC combination with DOX could act as effective cocktail therapy targeting autophagy and PI3K/AKT/mTOR pathways in MCF-7 breast cancer cells and hence, sensitizes cancer cells to doxorubicin treatment and combat its toxicity.

Autophagy and cardiac diseases: Therapeutic potential of natural products

The global incidence of cardiac diseases is expected to increase in the coming years, imposing a substantial socioeconomic burden on healthcare systems. Autophagy is a tightly regulated lysosomal degradation mechanism important for cell survival, homeostasis, and function. Accumulating pieces of evidence have indicated a major role of autophagy in the regulation of cardiac homeostasis and function. It is well established that dysregulation of autophagy in cardiomyocytes is involved in cardiac hypertrophy, myocardial infarction, diabetic cardiomyopathy, and heart failure. In this sense, autophagy seems to be an attractive therapeutic target for cardiac diseases. Recently, multiple natural products/phytochemicals, such as resveratrol, berberine, and curcumin have been shown to regulate cardiomyocyte autophagy via different pathways. The autophagy-modifying capacity of these compounds should be taken into consideration for designing novel therapeutic agents. This review focuses on the role of autophagy in various cardiac diseases and the pharmacological basis and therapeutic potential of reported natural products in cardiac diseases by modifying autophagic processes.

Combined Extracts of Epimedii Folium and Ligustri Lucidi Fructus with Budesonide Attenuate Airway Remodeling in the Asthmatic Rats by Regulating Apoptosis and Autophagy

This study aimed to investigate the effects of the coadministration of budesonide (Bud) and the extracts of Epimedii Folium and Ligustri Lucidi Fructus (EEL) on regulating apoptosis and autophagy in asthmatic rats. Forty Sprague-Dawley rats were divided randomly into five groups (8 rats in each group): normal control (control), asthma model (asthma), Bud (1 mg Bud suspension in 50 ml sterile physiological saline for 30 min), EEL (100 mg/kg EEL), and group of coadministration of Bud and EEL (Bud&EEL, 100 mg/kg EEL plus Bud by nebulized inhalation for 30 min). Rats were sensitized and challenged with ovalbumin for 7 weeks and treated with corresponding drug for 4 weeks. We anesthetized all rats with 25% ethyl carbamate (4 ml/kg) and took lung tissues and BALF after final ovalbumin challenge to observe the lung histopathology and morphometry; apoptosis in BALF and lung tissue; protein expressions of Ki-67, α-SMA, cleaved Caspase-3, p-mTOR, and LC3; and protein and mRNA expressions of Bax, Bcl-2, Caspase-3, P53, mTOR, and Beclin-1. Results showed that Bud&EEL could alleviate airway remodeling, inhibit cell proliferation and autophagy in lung tissue, and promote apoptosis in BALF and lung tissue in ovalbumin-induced asthma rats through downregulating the protein expressions of α-SMA and Ki-67, the protein ratio of LC3-II/LC3-I and Bcl-2/Bax, and the protein and mRNA expressions of Bcl-2 and Beclin-1, while upregulating the protein expressions of cleaved Caspase-3 and p-mTOR, and the protein and mRNA expressions of Bax, Caspase-3, P53, and mTOR. Bud&EEL had better effects than single-use Bud on improving airway remodeling, promoting apoptosis, and regulating the expressions of autophagy- and apoptosis-related proteins. This study suggested that the effects of coadministration of EEL and Bud on regulating apoptosis and autophagy were better than those of single-use Bud treatment, and that might be the mechanism of attenuating airway remodeling, providing an alternative therapy for asthma.

Cardiac Damage in Anthracyclines Therapy: Focus on Oxidative Stress and Inflammation

Significance: Despite their serious side effects, anthracyclines (ANTs) are the most prescribed chemotherapeutic drugs because of their strong efficacy in both solid and hematological tumors. A major limitation to ANTs clinical application is the severe cardiotoxicity observed both acutely and chronically. The mechanism underlying cardiac dysfunction under chemotherapy is mainly dependent on the generation of oxidative stress and systemic inflammation, both of which lead to progressive cardiomyopathy and heart failure. Recent Advances: Over the years, the iatrogenic ANTs-induced cardiotoxicity was believed to be simply given by iron metabolism and reactive oxygen species production; however, several experimental data indicate that ANTs may use alternative damaging mechanisms, such as topoisomerase 2β inhibition, inflammation, pyroptosis, immunometabolism, and autophagy. Critical Issues: In this review, we aimed at discussing ANTs-induced cardiac injury from different points of view, updating and focusing on oxidative stress and inflammation, since these pathways are not exclusive or independent from each other but they together importantly contribute to the complexity of ANTs-induced multifactorial cardiotoxicity. Future Directions: A deeper understanding of the mechanistic signaling leading to ANTs side effects could reveal crucial targeting molecules, thus representing strategic knowledge to promote better therapeutic efficacy and lower cardiotoxicity during clinical application.

Signaling Pathways Underlying Anthracycline Cardiotoxicity

Significance: The cardiac side effects of hematological treatments are a major issue of the growing population of cancer survivors, often affecting patient survival even more than the tumor for which the treatment was initially prescribed. Among the most cardiotoxic drugs are anthracyclines (ANTs), highly potent antitumor agents, which still represent a mainstay in the treatment of hematological and solid tumors. Unfortunately, diagnosis, prevention, and treatment of cardiotoxicity are still unmet clinical needs, which call for a better understanding of the molecular mechanism behind the pathology. Recent Advances: This review article will discuss recent findings on the pathomechanisms underlying the cardiotoxicity of ANTs, spanning from DNA and mitochondrial damage to calcium homeostasis, autophagy, and apoptosis. Special emphasis will be given to the role of reactive oxygen species and their interplay with major signaling pathways. Critical Issues: Although new promising therapeutic targets and new drugs have started to be identified, their efficacy has been mainly proven in preclinical studies and requires clinical validation. Future Directions: Future studies are awaited to confirm the relevance of recently uncovered targets, as well as to identify new druggable pathways, in more clinically relevant models, including, for example, human induced pluripotent stem cell-derived cardiomyocytes.

The Role of AMPK Activation for Cardioprotection in Doxorubicin-Induced Cardiotoxicity

Doxorubicin is a commonly used chemotherapeutic agent for the treatment of a range of cancers, but despite its success in improving cancer survival rates, doxorubicin is cardiotoxic and can lead to congestive heart failure. Therapeutic options for this patient group are limited to standard heart failure medications with the only drug specific for doxorubicin cardiotoxicity to reach FDA approval being dexrazoxane, an iron-chelating agent targeting oxidative stress. However, dexrazoxane has failed to live up to its expectations from preclinical studies while also bringing up concerns about its safety. Despite decades of research, the molecular mechanisms of doxorubicin cardiotoxicity are still poorly understood and oxidative stress is no longer considered to be the sole evil. Mitochondrial impairment, increased apoptosis, dysregulated autophagy and increased fibrosis have also been shown to be crucial players in doxorubicin cardiotoxicity. These cellular processes are all linked by one highly conserved intracellular kinase: adenosine monophosphate-activated protein kinase (AMPK). AMPK regulates mitochondrial biogenesis via PGC1α signalling, increases oxidative mitochondrial metabolism, decreases apoptosis through inhibition of mTOR signalling, increases autophagy through ULK1 and decreases fibrosis through inhibition of TGFβ signalling. AMPK therefore sits at the control point of many mechanisms shown to be involved in doxorubicin cardiotoxicity and cardiac AMPK signalling itself has been shown to be impaired by doxorubicin. In this review, we introduce different agents known to activate AMPK (metformin, statins, resveratrol, thiazolidinediones, AICAR, specific AMPK activators) as well as exercise and dietary restriction, and we discuss the existing evidence for their potential role in cardioprotection from doxorubicin cardiotoxicity.

Molecular Mechanism of Autophagy: Its Role in the Therapy of Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder of progressive dementia that is characterized by the accumulation of beta-amyloid (Aβ)-containing neuritic plaques and intracellular Tau protein tangles. This distinctive pathology indicates that the protein quality control is compromised in AD. Autophagy functions as a "neuronal housekeeper" that eliminates aberrant protein aggregates by wrapping then into autophagosomes and delivering them to lysosomes for degradation. Several studies have suggested that autophagy deficits in autophagy participate in the accumulation and propagation of misfolded proteins (including Aβ and Tau). In this review, we summarize current knowledge of autophagy in the pathogenesis of AD, as well as some pathways targeting the restoration of autophagy. Moreover, we discuss how these aspects can contribute to the development of disease-modifying therapies in AD.

β-LAPachone ameliorates doxorubicin-induced cardiotoxicity via regulating autophagy and Nrf2 signalling pathways in mice

β-LAPachone (B-LAP) is a naphthoquinone that possesses antioxidant properties. In the present investigation, the protective effect of B-LAP against doxorubicin (DOX)-induced cardiotoxicity was examined in mice. Thirty-five mice were divided into 5 groups: control group, B-LAP (5 mg/kg) group, DOX (15 mg/kg) group, DOX+B-LAP (2.5 mg/kg) group and DOX+B-LAP (5 mg/kg) group. B-LAP was administered orally for 14 days of experimental period. A single dose of DOX (15 mg/kg) was injected intraperitoneally on day 3. Cardiac function, histoarchitecture, indices of oxidative stress and circulating markers of cardiac injury were examined. B-LAP (5 mg/kg) decreased serum levels of lactate dehydrogenase (LDH), creatine kinase MB (CK-MB) and cardiac troponin I (cTnI), and ameliorated cardiac histopathological alterations. In addition to increasing cellular NAD⁺ /NADH ratio, B-LAP up-regulated the cardiac levels of SIRT1, beclin-1, p-LKB1 and p-AMPK, and reduced the cardiac levels of p-mTOR, interleukin (IL)-1β, TNF (tumour necrosis factor)-α and caspase-3. B-LAP also elevated the nuclear accumulation of Nrf2 and simultaneously up-regulated the protein levels of haem oxygenase (HO-1) and glutathione S-transferase (GST) in the hearts of DOX mice. While B-LAP reduced malondialdehyde concentrations in heart of DOX-treated mice, it further promoted the activities of cardiac superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT).In accordance with increased cell survival, B-LAP significantly improved the cardiac function of DOX mice. Collectively, these findings underline the protective potential of B-LAP against DOX-induced cardiotoxicity by regulating autophagy and AMPK/Nrf2 signalling pathway in mice.

Dihydrochalcone Derivative Induces Breast Cancer Cell Apoptosis via Intrinsic, Extrinsic, and ER Stress Pathways but Abolishes EGFR/MAPK Pathway

Dihydrochalcone derivatives are active compounds that have been purified from the Thai medicinal plant Cyathostemma argenteum. The objectives of this study were to investigate the effects of two dihydrochalcone derivatives on human breast cancer MDA-MB-231 and MCF-7 cell proliferation and to study the relevant mechanisms involved. The two dihydrochalcone derivatives are 4′,6′-dihydroxy-2′,4-dimethoxy-5′-(2″-hydroxybenzyl)dihydrochalcone (compound 1) and calomelanone (2′,6′-dihydroxy-4,4′-dimethoxydihydrochalcone, compound 2), both of which induced cytotoxicity toward both cell lines in a dose-dependent manner by using MTT assay. Treatment with both derivatives induced apoptosis as determined by annexin V-FITC/propidium iodide employing flow cytometry. The reduction of mitochondrial transmembrane potential (staining with 3,3′-dihexyloxacarbocyanine iodide, DiOC₆, employing a flow cytometer) was established in the compound 1-treated cells. Compound 1 induced caspase-3, caspase-8, and caspase-9 activities in both cell lines, as has been determined by specific colorimetric substrates and a spectrophotometric microplate reader which indicated the involvement of both the extrinsic and intrinsic pathways. Calcium ion levels in mitochondrial and cytosolic compartments increased in compound 1-treated cells as detected by Rhod-2AM and Fluo-3AM intensity, respectively, indicating the involvement of the endoplasmic reticulum (ER) stress pathway. Compound 1 induced cell cycle arrest via enhanced atm and atr expressions and by upregulating proapoptotic proteins, namely, Bim, Bad, and tBid. Moreover, compound 1 significantly inhibited the EGFR/MAPK signaling pathway. In conclusion, compound 1 induced MDA-MB-231 and MCF-7 cell apoptosis via intrinsic, extrinsic, and ER stress pathways, whereas it ameliorated the EGFR/MAPK pathway in the MCF-7 cell line. Consequently, it is believed that compound 1 could be effectively developed for cancer treatments.

Targeted and pH-facilitated theranostic of orthotopic gastric cancer via phase-transformation doxorubicin-encapsulated nanoparticles enhanced by low-intensity focused ultrasound (LIFU) with reduced side effect

Purpose

Focused ultrasound-mediated chemotherapy, as a non-invasive therapeutic modality, has been extensively explored in combating deep tumors for predominant penetration performance. However, the generally used high-intensity focused ultrasound (HIFU) inevitably jeopardizes normal tissue around the lesion for hyperthermal energy. To overcome this crucial issue, low-intensity focused ultrasound (LIFU) was introduced to fulfill precisely controlled imaging and therapy in lieu of HIFU. The objective of this study was to develop a facile and versatile nanoplatform (DPP-R) in response to LIFU and provide targeted drug delivery concurrently.

Methods

Multifunctional DPP-R was fabricated by double emulsion method and carbodiimide method. Physicochemical properties of DPP-R were detected respectively and the bio-compatibility and bio-safety were evaluated by CCK-8 assay, blood analysis, and histologic section. The targeted ability, imaging function, and anti-tumor effect were demonstrated in vitro and vivo.

Results

The synthetic DPP-R showed an average particle size at 367 nm, stable physical-chemical properties in different media, and high bio-compatibility and bio-safety. DPP-R was demonstrated to accumulate at the tumor site by active receptor/ligand reaction and passive EPR effect with intravenous administration. Stimulated by LIFU at the tumor site, phase-transformable PFH was vaporized in the core of the integration offering contrast-enhanced ultrasound imaging. The stimuli led to encapsulated DOX's initial burst release and subsequent sustained release for anti-tumor therapy which was verified to be more effective and have less adverse effects than free DOX.

Conclusion

DPP-R combined with LIFU provides a novel theranostic modality for GC treatment with potent therapeutic effect, including prominent performance of targeting, ultrasound imaging, and accurate drug release.

miR-146a attenuates apoptosis and modulates autophagy by targeting TAF9b/P53 pathway in doxorubicin-induced cardiotoxicity

Clinical therapy of doxorubicin (DOX) is limited due to its cardiotoxicity. miR-146a was proved as a protective factor in many cardiovascular diseases, but its role in chronic DOX-induced cardiotoxicity is unclear. The objective of this study was to demonstrate the role of miR-146a in low-dose long-term DOX-induced cardiotoxicity. Experiments have shown that DOX intervention caused a dose-dependent and time-dependent cardiotoxicity involving the increased of apoptosis and dysregulation of autophagy. The cardiotoxicity was inhibited by overexpressed miR-146a and was more severe when miR-146a was downgraded. Further research proved that miR-146a targeted TATA-binding protein (TBP) associated factor 9b (TAF9b), a coactivator and stabilizer of P53, indirectly destroyed the stability of P53, thereby inhibiting apoptosis and improving autophagy in cardiomyocytes. Besides, miR-146a knockout mice were used for in vivo validation. In the DOX-induced model, miR-146a deficiency made it worse whether in cardiac function, cardiomyocyte apoptosis or basal level of autophagy, than wild-type. In conclusion, miR-146a partially reversed the DOX-induced cardiotoxicity by targeting TAF9b/P53 pathway to attenuate apoptosis and adjust autophagy levels.

The true colors of autophagy in doxorubicin-induced cardiotoxicity

Patients with cancer receiving doxorubicin-based chemotherapy often have to stop taking the drug due to its cardiotoxicity and therefore lose out on the beneficial effects of its potent antitumor activity. Doxorubicin has been demonstrated to damage cardiomyocytes via various mechanisms, including accumulation of reactive oxygen species (ROS), DNA damage and autophagy dysfunction. The present review focuses on autophagy, describing the general process of autophagy and the controversy surrounding its role in doxorubicin-induced cardiotoxicity. In addition, the associations between autophagy and apoptosis, ROS, DNA damage and inflammatory processes are discussed. In the future, it will be useful to further elucidate the process of autophagy and reveal its association with various pathological processes to develop effective strategies of preventing doxorubicin-induced cardiotoxicity.

Fluvastatin attenuates doxorubicin-induced testicular toxicity in rats by reducing oxidative stress and regulating the blood–testis barrier via mTOR signaling pathway

Doxorubicin (DOX) is an anthracycline derivative antibiotic that still frequently used in the treatment of solid tumors and hematological malignancies. The clinical use of DOX is largely restricted due to acute and chronic renal, cardiac, hematological, and testicular toxicities. Previous studies have indicated that oxidative stress, lipid peroxidation, and apoptosis in germ cells are the main factors in DOX-induced testicular toxicity, but the entire molecular mechanisms that responsible for DOX-induced testicular damage are not yet fully understood. Fluvastatin is a cholesterol-lowering agent that acts by inhibiting hydroxylmethyl glutaryl coenzyme A, the key enzyme for cholesterol biosynthesis. In addition to its cholesterol-lowering effect, fluvastatin showed an antioxidant effect by cleaning hydroxyl and superoxide radicals and this drug could have a protective effect by acting on the mammalian target of rapamycin (mTOR) signal pathway in testicular damage caused by obesity. This study aimed to investigate the possible protective and therapeutic effects of fluvastatin on the DOX-induced testicular toxicity model by histochemical, immunohistochemical, biochemical, and real-time polymerase chain reaction analyses. The present study indicates that fluvastatin may have a protective and therapeutic effect by removing reactive oxygen species and by regulating the mTOR, connexin 43, and matrix metalloproteinase 9 protein and messenger ribonucleic acid expressions, which play an important role in regulating the blood–testis barrier. On the other hand, the use of fluvastatin as a protective/prophylactic agent was found to be more effective than the use of this drug for treatment. In light of this information, fluvastatin may be a candidate agent that can be used to prevent testicular toxicity observed in men receiving DOX treatment.

Long-term administration of Aspalathus linearis infusion affects spatial memory of adult Sprague-Dawley male rats as well as increases their striatal dopamine content

ETHNOPHARMACOLOGICAL RELEVANCE

Everyday use of the herbal tea rooibos, produced from Aspalathus linearis (Brum.f) Dahlg. (Fabaceae) is customary in South Africa, a continuation of its historical use by indigenous people. Although evidence of its traditional indications is anecdotal, rooibos tea is regarded as a general health tea.

AIMS OF THE STUDY

Available contemporary research indicates to broad cell protective activity of rooibos focusing on its antioxidative, anti-inflammatory, anti-hyperglycaemic and antithrombotic features affecting metabolic syndrome, cardiovascular risk and neuroprotection. Nevertheless little is known about its impact on brain functions. The present experiment aimed to evaluate the possible behavioural and neurochemical effects of long-term oral administration of "fermented"" rooibos herbal tea (FRHT) infusions to adult male Sprague-Dawley rats.

MATERIALS AND METHODS

Infusions, prepared using 1, 2 and 4 g of "fermented"" (oxidised) A. linearis leaves for 100 ml of hot water, were characterised in terms of flavonoid content by ultra-high and high performance liquid chromatography (UHPLC-qTOF-MS, HPLC-DAD) and administered to rats as sole drinking fluid for 12 weeks. Spatial memory behaviour was assessed in a modified version of the Morris water maze. Dopamine, noradrenaline, serotonin and their metabolite levels (DOPAC, 3-MT, HVA, MHPG, 5-HIAA) were quantified in prefrontal cortex, hippocampus and striatum by HPLC-ECD. Body weight and blood glucose level were additionally estimated.

RESULTS

All FRHT-treated rats showed improvement of long-term spatial memory defined as increased number of crossings over the previous platform position in SE quadrant of the water maze. It was not accompanied by excessive motor activity. Striatal dopamine and its metabolite 3-MT (3-methoxytyramine) levels were increased in treated rats. There were no differences in body weight gain between control and treated animals but blood glucose level was significantly lower in the latter ones.

CONCLUSION

The improvement of long-term memory in FRHT-treated rats and stimulating impact of FRHT on their dopaminergic striatal transmission support the wellness enhancing effect of rooibos tea, contributing to a better understanding of the neurological background of traditional habitual consumption of this herbal tea.

SESN2 protects against doxorubicin-induced cardiomyopathy via rescuing mitophagy and improving mitochondrial function

The clinical application of doxorubicin (Dox) in cancer therapy is limited by its serious cardiotoxicity. Our previous studies and others have recognized that mitochondrial dysfunction is the common feature of Dox-induced cardiotoxicity. However, mechanisms underlying mitochondrial disorders remained largely unknown. SESN2, a highly conserved and stress-inducible protein, is involved in mitochondrial function and autophagy in cardiovascular diseases. This study aimed to investigate whether SESN2 affects Dox-induced cardiotoxicity and the underlying mechanisms. Sprague-Dawley rats and neonatal rat cardiomyocytes were treated with Dox. SESN2 expression was assessed. The effects of SESN2 on Dox-induced cardiotoxicity were assessed by functional gain and loss experiments. Echocardiographic parameters, morphological and histological analyses, transmission electron microscope and immunofluorescence assays were used to assess cardiac and mitochondrial function. The protein expression of SESN2 was significantly reduced following Dox stimulation. Both knockout of SESN2 by sgRNA and Dox treatment resulted in the inhibition of Parkin-mediated mitophagy, marked cardiomyocytes apoptosis and mitochondria dysfunction. Ectopic expression of SESN2 effectively protected against Dox-induced cardiomyocyte apoptosis, mitochondrial injury and cardiac dysfunction. Mechanistically, SESN2 interacted with Parkin and p62, promoted accumulation of Parkin to mitochondria and then alleviated Dox-caused inhibition of Parkin mediated mitophagy. Ultimately, the clearance of damaged mitochondria and mitochondrial function were improved following SESN2 overexpression. SESN2 protected against Dox-induced cardiotoxicity through improving mitochondria function and mitophagy. These results established SESN2 as a key player in mitochondrial function and provided a potential therapeutic approach to Dox-induced cardiomyopathy.

Quercetin protects cardiomyocytes against doxorubicin-induced toxicity by suppressing oxidative stress and improving mitochondrial function via 14-3-3γ

Cardiotoxicity limits the clinical applications of doxorubicin (Dox), which mechanism might be excess generation of intracellular ROS. Quercetin (Que) is a flavonoid that possesses anti-oxidative activities, exerts myocardial protection. We hypothesized that the cardioprotection against Dox injury of Que involved 14-3-3γ, and mitochondria. To investigate the hypothesis, we treated primary cardiomyocytes with Dox and determined the effects of Que pretreatment with or without 14-3-3γ knockdown. We analyzed various cellular and molecular indexes. Our data showed that Que attenuated Dox-induced toxicity in cardiomyocytes by upregulating 14-3-3γ expression. Que pretreatment increased cell viability, SOD, catalase, and GPx activities, GSH levels, MMP and the GSH/GSSG ratio; decreased LDH and caspase-3 activities, MDA and ROS levels, mPTP opening and the percentage of apoptotic cells. However, Que's cardioprotection were attenuated by knocking down 14-3-3γ expression using pAD/14-3-3γ-shRNA. In conclusion, Que protects cardiomyocytes against Dox injury by suppressing oxidative stress and improving mitochondrial function via 14-3-3γ.

Molecular basis of the anti-hyperglycemic activity of RA-3 in hyperlipidemic and streptozotocin-induced type 2 diabetes in rats

BACKGROUND

Insulin resistance is a hallmark of type 2 diabetes mellitus (T2DM) and the underlying cause of various metabolic changes observed in type 2 diabetic patients. This study investigated the molecular basis of the anti-hyperglycemic activity of the lanosteryl triterpene (RA-3), from Protorhus longifolia stem bark, in hyperlipidemic and streptozotocin (STZ)-induced T2DM in rats.

METHODS

The high-fat diet fed (HFD) and STZ-induced T2DM in rat model was used to evaluate the anti-hyperglycemic activity of RA-3. The hyperlipidemic rats received a single intraperitoneal injection of STZ (35 mg/kg body weight) to induce T2DM. The experimental animals received a daily oral single dose of RA-3 (100 mg/kg body) for a period of 28 days, whiles the control group received distilled water only. The animals were euthanized, and skeletal muscle was collected for protein (IRS-1, AKT, GSK and GLUT 4) expression analysis. Western blot confirmed expression of the proteins.

RESULTS

Treatment of the diabetic animals with the RA-3 showed marked reduction in fasting plasma glucose levels in comparison to the untreated diabetic group animals. A significant decrease in p-GSK-3β and p-AKT expression was observed, whereas the expression of IRS-1^ser307 were increased when compared to the diabetic control group. This effect was ablated upon treatment with RA-3 and this was concomitant to an observed increase in GLUT 4 expression.

CONCLUSIONS

The results obtained in the present study strongly suggested that the anti-hyperglycemic effect of RA-3 could partly be associated with its ability to improve cellular glucose uptake in muscle tissue from T2DM.

Aspalathin ameliorates doxorubicin-induced oxidative stress in H9c2 cardiomyoblasts

Aspalathin (ASP) is a C-dihydrochalcone abundantly found in Aspalathus linearis. While we have provide evidence that ASP can protect H9c2 cardiomyoblasts against doxorubicin (Dox)-induced apoptosis through regulation of autophagy, the complete mechanism involved in the cardioprotective effect of this dihydrochalcone remains to be explored. Here we provide evidence that ASP reverses Dox-induced apoptosis through the amelioration of oxidative stress in H9c2 cardiomyoblasts. Cultured cells were treated with 0.2 μM Dox or co-treated with either 20 μM dexrazoxane (Dexra) or 0.2 μM ASP daily for five days, to a final dose of 1 μM Dox, 100 μM Dexra and 1 μM ASP, respectively. Superoxide dismutase, catalase, glutathione, malondialdehyde and dichloro-dihydro-fluorescein diacetate fluorescence were used as end-point measurements for oxidative stress, while JC-1 and TUNEL labeling were performed to assess mitochondria depolarization and apoptosis. Co-treatment with ASP attenuated Dox-induced cardiotoxicity by improving endogenous antioxidant levels and mitochondrial membrane potential, while inhibiting reactive oxygen species production and cellular apoptosis. These findings suggested that ASP can prevent Dox-induced oxidative stress and apoptosis and needs further assessment to confirm its therapeutic potential to prevent Dox-induced cardiotoxicity.

Curcumin attenuates doxorubicin-induced cardiotoxicity via suppressing oxidative stress and preventing mitochondrial dysfunction mediated by 14-3-3γ

Doxorubicin (Dox) induces cardiotoxicity, thereby limiting its clinical application for chemotherapy of cancer. The mechanism of cardiotoxicity includes the production of excess intracellular ROS. 14-3-3s have been found to protect the myocardium against various types of injury. Curcumin (Cur) is a polyphenolic compound that is derived from turmeric and has multiple bioactivities, including anti-oxidative and radical-scavenging activities that exert cytoprotection. We hypothesize that the cardioprotective effects of Cur are exerted by regulating 14-3-3γ. To test the hypothesis, Dox-induced cardiotoxicity was used to establish an in vivo myocardial injury model in mice (in vivo) and primary cardiomyocytes (in intro). The effects of Cur were assessed by determining the heart rate and ECG's ST segments, as well as lactate dehydrogenase (LDH) and creatine kinase (CK) activities in the serum, caspase-3 activity, apoptosis rate, and histopathological changes of the myocardium (in vivo). In addition, cell viability, LDH, SOD, CAT, GPx, and caspase-3 activities, levels of ROS, MDA, and MMP, mPTP opening, and the apoptosis rate (in vitro) were evaluated. The expression of 14-3-3γ and Bcl-2 as well as the phosphorylation levels of Bad (S112) were determined by western blot analysis. Our results showed that Dox-induced injury to the myocardium was decreased by Cur treatment via upregulating the protein expression of 14-3-3γ in total protein and Bcl-2 expression on mitochondria, activating Bad (S112) phosphorylation, reducing the heart rate and ST segment, and reducing LDH and CK activities in the serum, thereby causing a reduction in caspase-3 activity, the apoptosis rate, and histopathological changes of the myocardium (in vivo). Furthermore, Dox treatment increased cell viability and MMP levels, decreased LDH and caspase-3 activity, ROS levels, mPTP opening, and the apoptosis rate (in vitro). However, the cardioprotective effects of Cur were attenuated by pAD/14-3-3γ-shRNA, an adenovirus that caused a knock-down of intracellular 14-3-3γ expression. In conclusion, this is the first study to demonstrate that Cur protected the myocardium against Dox-induced injury via upregulating 14-3-3γ expression, thereby promoting the translocation of Bcl-2 to mitochondria, suppressing oxidative stress, and improving mitochondrial function.

A Lanosteryl triterpene from Protorhus longifolia augments insulin signaling in type 1 diabetic rats

BACKGROUND

A substantial literature supports antidiabetic properties of the lanosteryl triterpene (methyl-3β-hydroxylanosta-9,24-dien-21-oate, RA-3) isolated from Protorhus longifolia stem bark. However, the molecular mechanism(s) associated with the antihyperglycemic properties of the triterpene remained to be explored. The current study aimed at investigating the molecular mechanism(s) through which RA-3 improves insulin signaling in streptozotocin-induced type 1 diabetic rats.

METHODS

The type 1 diabetic rats were treated daily with a single oral dose of RA-3 (100 mg/kg) for 28 days. The rats were then sacrificed, and blood, skeletal muscle and pancreases were collected for biochemical, protein expression and histological analysis, respectively.

RESULTS

Persistently high blood glucose levels in the diabetic control rats significantly increased expression of IRS-1Ser307 while the expression of p-Akt Ser473, p-GSK-3β Ser9, GLUT 4 and GLUT 2 were decreased. However, enhanced muscle insulin sensitivity, which was indicated by a decrease in the expression of IRS-1ser307 with a concomitant increase in the p-AktSer473, p-GSK-3β Ser9, GLUT 4 and GLUT 2 expression were observed in the diabetic rats treated with RA-3. The triterpene-treated animals also showed an improved pancreatic β-cells morphology, along with increased C-peptide levels. An increase in the levels of serum antioxidants such as catalase, superoxide dismutase, and reduced glutathione was noted in the rats treated with the triterpene, while their serum levels of interleukin-6 and malondialdehyde were reduced.

CONCLUSIONS

It is apparent that RA-3 is able to improve the insulin signaling in type 1 diabetic rats. Its beta (β)-cells protecting mechanism could be attributed to its ability to alleviate inflammation and oxidative stress in the cells.

Phytochemicals as potent modulators of autophagy for cancer therapy

The dysregulation of autophagy is involved in the pathogenesis of a broad range of diseases, and accordingly universal research efforts have focused on exploring novel compounds with autophagy-modulating properties. While a number of synthetic autophagy modulators have been identified as promising cancer therapy candidates, autophagy-modulating phytochemicals have also attracted attention as potential treatments with minimal side effects. In this review, we firstly highlight the importance of autophagy and its relevance in the pathogenesis and treatment of cancer. Subsequently, we present the data on common phytochemicals and their mechanism of action as autophagy modulators. Finally, we discuss the challenges associated with harnessing the autophagic potential of phytochemicals for cancer therapy.

Reversal of Doxorubicin-induced Cardiotoxicity by Using Phytotherapy: A Review

Doxorubicin as a chemotherapeutic drug is widely used for the treatment of patients with cancer. However, clinical use of this drug is hampered by its cardiotoxicity, which is manifested as electrocardiographic abnormalities, arrhythmias, irreversible degenerative cardiomyopathy and congestive heart failure. The precise mechanisms underlying the cardiotoxicity of doxorubicin are not clear, but impairment of calcium homeostasis, generation of iron complexes, production of oxygen radicals, mitochondrial dysfunction and cell membrane damage have been suggested as potential etiologic factors. Compounds that can neutralize the toxic effect of doxorubicin on cardiac cells without reducing the drug's antitumor activity are needed. In recent years, numerous studies have shown that herbal medicines and bioactive phytochemicals can serve as effective add-on therapies to reduce the cardiotoxic effects of doxorubicin. This review describes different phytochemicals and herbal products that have been shown to counterbalance doxorubicin-induced cardiotoxicity.

Klotho Improves Cardiac Function by Suppressing Reactive Oxygen Species (ROS) Mediated Apoptosis by Modulating Mapks/Nrf2 Signaling in Doxorubicin-Induced Cardiotoxicity

Background

Anthracyclines-induced cardiotoxicity has become one of the major restrictions of their clinical applications. Klotho showed cardioprotective effects. This study aimed to investigate the effects and possible mechanisms of klotho on doxorubicin (DOX)-induced cardiotoxicity.

Material/Methods

Rats and isolated myocytes were exposed to DOX and treated with exogenous klotho. Specific inhibitors and siRNAs silencing MAPKs were also used to treat the animals and/or myocytes. An invasive hemodynamic method was used to determine cardiac functions. Intracellular ROS generation was evaluated by DHE staining. Western blotting was used to determine the phosphorylation levels of JNK, ERK, and p38 MAPKs in plasma extracts and Nrf2 in nuclear extracts. Nuclear translocation of Nrf2 in myocytes was evaluated by immunohistochemistry. Cell apoptosis was evaluated by TUNEL assay and flow cytometry.

Results

Klotho treatment improved DOX-induced cardiac dysfunction in rats. The DOX-induced ROS accumulation and cardiac apoptosis were attenuated by klotho. Impaired phosphorylations of MAPKs, Nrf2 translocation and expression levels of HO1 and Prx1 were also attenuated by klotho treatment. However, the anti-oxidant and anti-apoptotic effects of klotho on DOX-exposed myocardium and myocytes were impaired by both specific inhibitors and siRNAs against MAPKs. Moreover, the recovery effects of klotho on phosphorylations of MAPKs, Nrf2 translocation and expression levels of HO1 and Prx1 were also impaired by specific inhibitors and siRNAs against MAPKs.

Conclusions

By recovering the activation of MAPKs signaling, klotho improved cardiac function loss which was triggered by DOX-induced ROS mediated cardiac apoptosis.