Hesperidin Induces Apoptosis by Inhibiting Sp1 and Its Regulatory Protein in MSTO-211H Cells

Hesperidin, a Bioflavonoid in Cancer Therapy: A Review for a Mechanism of Action through the Modulation of Cell Signaling Pathways

Cancer represents one of the most frequent causes of death in the world. The current therapeutic options, including radiation therapy and chemotherapy, have various adverse effects on patients' health. In this vista, the bioactive ingredient of natural products plays a vital role in disease management via the inhibition and activation of biological processes such as oxidative stress, inflammation, and cell signaling molecules. Although natural products are not a substitute for medicine, they can be effective adjuvants or a type of supporting therapy. Hesperidin, a flavonoid commonly found in citrus fruits, with its potential antioxidant, anti-inflammatory, and hepatoprotective properties, and cardio-preventive factor for disease prevention, is well-known. Furthermore, its anticancer potential has been suggested to be a promising alternative in cancer treatment or management through the modulation of signal transduction pathways, which includes apoptosis, cell cycle, angiogenesis, ERK/MAPK, signal transducer, and the activator of transcription and other cell signaling molecules. Moreover, its role in the synergistic effects with anticancer drugs and other natural compounds has been described properly. The present article describes how hesperidin affects various cancers by modulating the various cell signaling pathways.

Hesperidin protects against aluminum-induced renal injury in rats via modulating MMP-9 and apoptosis: biochemical, histological, and ultrastructural study

Aluminum, one of the most abundant metallic elements, is known to be toxic to multiple organs including the kidneys. This study aimed to investigate the pleiotropic nephroprotective effects of Hesperidin in aluminum chloride (ALCL3)-induced renal injury, highlighting the potential molecular mechanisms underlying. Twenty-four male albino rats were divided into four groups: control, Hesperidin (80 mg/kg BW, orally), ALCL3 (10 mg/kg BW, IP), and ALCL3 + Hesperidin groups. By the end of the study, blood samples were collected, and tissue samples were harvested at sacrifice. ALCL3 rats showed dramatically declined renal function, enhanced intrarenal oxidative stress, inflammation, apoptosis, and extravagant renal histopathological damage with interstitial fibrosis as shown by a higher Endothelial, Glomerular, Tubular, and Interstitial (EGTI) score. Hesperidin significantly reversed all the aforementioned detrimental effects in ALCL3-treated rats. The study verified the nephroprotective effects of Hesperidin on ALCL3-induced renal damage and confirmed the critical role of extracellular matrix (ECM) remodeling and apoptosis inhibition.

Evidence for Hesperidin as an Effective Factor in Initiating the Intrinsic Pathway of Apoptosis in KG1a Leukemia Cells

Acute myeloid leukemia (AML) is the most common subtype of leukemia, accounting for 62% of all leukemia fatalities. As a polyphenol glycoside, hesperidin triggers the apoptotic pathway, which might positively affect combating cancer cells. In this study, we investigated the pro-apoptotic effects of hesperidin in KG1a cells. The MTT assay was used to determine the IC₅₀ of hesperidin in KG1a cell lines. For the apoptotic cell morphology study, we used Hoechst 33 258 staining. Activation of the caspase-3 enzyme was evaluated by the caspase-3 assay and spectrophotometry. Cell cycle distribution was analyzed by propidium iodide staining and flow cytometry. Moreover, p21, survivin, Bax, and Bcl2 gene expression was investigated by real-time PCR. Hesperidin decreased the viability of KG1a leukemic cell4s, but not that of HFF2, a non-cancer cell line. Apoptotic cell morphological alterations and increase in caspase-3 activity were observed after hesperidin treatment. Our results revealed that the expression of anti-apoptotic genes survivin and Bcl2 significantly decreased with hesperidin treatment, and pro-apoptotic gene Bax and cell cycle regulator p21 increased compared to the control group. These findings revealed that hesperidin may be an effective factor in initiating the intrinsic pathway of apoptosis and may be good candidate for the treatment of AML.

Mechanism of Citri Reticulatae Pericarpium as an Anticancer Agent from the Perspective of Flavonoids: A Review

Citri Reticulatae Pericarpium (CRP), also known as “chenpi”, is the most common qi-regulating drug in traditional Chinese medicine. It is often used to treat cough and indigestion, but in recent years, it has been found to have multi-faceted anti-cancer effects. This article reviews the pharmacology of CRP and the mechanism of the action of flavonoids, the key components of CRP, against cancers including breast cancer, lung cancer, prostate cancer, hepatic carcinoma, gastric cancer, colorectal cancer, esophageal cancer, cervical cancer, bladder cancer and other cancers with a high diagnosis rate. Finally, the specific roles of CRP in important phenotypes such as cell proliferation, apoptosis, autophagy and migration–invasion in cancer were analyzed, and the possible prospects and deficiencies of CRP as an anticancer agent were evaluated.

Phytochemicals in Malignant Pleural Mesothelioma Treatment-Review on the Current Trends of Therapies

Malignant pleural mesothelioma (MPM) is a rare but highly aggressive tumor of pleura arising in response to asbestos fibers exposure. MPM is frequently diagnosed in the advanced stage of the disease and causes poor prognostic outcomes. From the clinical perspective, MPM is resistant to conventional treatment, thus challenging the therapeutic options. There is still demand for improvement and sensitization of MPM cells to therapy in light of intensive clinical studies on chemotherapeutic drugs, including immuno-modulatory and targeted therapies. One way is looking for natural sources, whole plants, and extracts whose ingredients, especially polyphenols, have potential anticancer properties. This comprehensive review summarizes the current studies on natural compounds and plant extracts in developing new treatment strategies for MPM.

'de Novo' repurposing of Daflon as anti-intestinal parasitic drug in experimental giardiasis

BACKGROUND

There is a necessity to develop or discover an alternative drug to combat the drug resistance by Giardia duodenalis and minimize the multiple doses and frequency of the conventional drug administration. Progressive repositioning or 'repurposing' of drugs has become widespread due to economic circumstances and medical emergency needs. Daflon 500 mg (DFL) is a natural product used safely as a nutrient supplement and an antidiabetic drug in many European countries and the US.

OBJECTIVE

This study aimed at investigating the efficiency of DFL, in vivo, in a murine model as a safe alternative or co-drug for giardiasis.

MATERIALS AND METHODS

Swiss Albino mice (n = 32) were inoculated with 1X10⁴Giardia cysts and assigned to four groups: One group was the infected non-treated control mice and three experimental groups that were treated differently, either with Metronidazole (MTZ), DFL, or combined therapy of DFL/MTZ. Also, eight normal mice served as a control group. All mice were sacrificed 13 days post-infection for the parasitic, histopathological, and oxidative stress analysis.

RESULTS

MTZ, DFL, and the combined therapy significantly reduced the number of trophozoites and cysts compared to their counterparts of the infected mice. The histopathological analysis of the small intestines of the mice treated with the combined therapy retained typical intestinal architecture and normal levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione.

CONCLUSION

This study indicated promising actions of Daflon 500 as an anti-giardial drug, and the results demonstrated its potential effect in improving the intestinal epithelial tissue and disturbing the Giardia stages when it was taken collectively with Metronidazole.

The Use of Bio-Active Compounds of Citrus Fruits as Chemopreventive Agents and Inhibitor of Cancer Cells Viability

Common therapy of cancer, such as chemotherapy, has various side effects for the patients. In recent studies, new therapeutic approaches in cancer treatment are adjuvant therapy, along with a reduction in side effects of chemotherapy drugs. Treatment by herbal medicines may have some advantages over treatment with single purified chemicals, also in terms of side effects, the use of plants in cancer treatment is a more secure method. Citrus fruits are one of the most consumed natural products in the world due to the presence of various metabolites and bioactive compounds, such as phenols, flavonoids and, carotenoids. Bioactive compounds of citrus modulate signaling pathways and interact with signaling molecules such as apoptotic and cell cycle (P53, P21, etc.) and thus have a wide range of pharmacological activities, including anti-inflammatory, anti-cancer and oxidative stress. The findings discussed in this review strongly support their potential as anti-cancer agents. Therefore, the purpose of this review was to examine the effects of active compounds in citrus as a therapy agent in cancer treatment.

Phytochemicals in Chemoprevention: A Cost-Effective Complementary Approach

Cancer is one of the leading causes of death across the world. Although conventional cancer treatments such as chemotherapy and radiotherapy have effectively decreased cancer progression, they come with many dose-limiting side-effects. Phytochemicals that naturally occur in spices, fruits, vegetables, grains, legumes, and other common foods are surprisingly effective complements to conventional cancer treatments. These biologically active compounds demonstrate anticancer effects via cell signaling pathway interference in cancerous cells. In addition, phytochemicals protect non-cancerous cells from chemotherapy-induced side-effects. This paper addresses the not only the potential of phytochemicals quercetin, isoflavones, curcumin, catechins, and hesperidin in terms of cancer treatment and protection against side-effects of chemotherapy, but also methods for increasing phytochemical bioavailability.

The protective effect of hesperidin against renal ischemia-reperfusion injury involves the TLR-4/NF-κB/iNOS pathway in rats

Renal injury is reported to have a high mortality rate. Additionally, there are several limitations to current conventional treatments that are used to manage it. This study evaluated the protective effect of hesperidin against ischemia/reperfusion (I/R)-induced kidney injury in rats. Renal injury was induced by generating I/R in kidney tissues. Rats were then treated with hesperidin at a dose of 10 or 20 mg/kg intravenously 1 day after surgery for a period of 14 days. The effect of hesperidin on renal function, serum mediators of inflammation, and levels of oxidative stress in renal tissues were observed in rat kidney tissues after I/R-induced kidney injury. Moreover, protein expression and mRNA expression in kidney tissues were determined using Western blotting and RT-PCR. Hematoxylin and eosin (H&E) staining was done for histopathological observation of kidney tissues. The data suggest that the levels of blood urea nitrogen (BUN) and creatinine in the serum of hesperidin-treated rats were lower than in the I/R group. Treatment with hesperidin also ameliorated the altered level of inflammatory mediators and oxidative stress in I/R-induced renal-injured rats. The expression of p-IκBα, caspase-3, NF-κB p65, Toll-like receptor 4 (TLR-4) protein, TLR-4 mRNA, and inducible nitric oxide synthase (iNOS) was significantly reduced in the renal tissues of hesperidin-treated rats. Histopathological findings also revealed that treatment with hesperidin attenuated the renal injury in I/R kidney-injured rats. In conclusion, our results suggest that hesperidin protects against renal injury induced by I/R by involving TLR-4/NF-κB/iNOS signaling.

Hesperidin ameliorates hepatic dysfunction and dyslipidemia in male Wistar rats exposed to cadmium chloride

The ever-increasing human population with attendant industrialization poses serious global health challenge. Cadmium (Cd) with other heavy metals contribute greatly to environmental pollutions and humans are daily exposed to them, leading to diverse ailments. We explored whether Hesperidin (HSP) could protect against hepatic damage and dyslipidemia in Wistar rats exposed to Cd. Forty wistar rats were randomly assigned into five groups (n = 8). Group 1 received 2 mL/kg body weight of normal saline; Group 2 received 100 mg/kg body weight of HSP while Group 3 received 5 mg/kg body weight of Cadmium Chloride (CdCl2) for 28 days. Group 4 received 100 mg/kg body weight of HSP and after 90 min, CdCl2 (5 mg/kg) body weight was administered for 28 days. Group 5 received 50 mg/kg body weight of HSP and after 90 min, CdCl2 (5 mg/kg) body weight was administered for 28 days. The serum lipid profiles, hepatic dysfunction and oxidative stress markers were determined using standard methods. Cd toxicity in rats prominently elevated serum activities of AST, ALT, ALP and levels of total bilirubin, direct bilirubin, cholesterol, LDL-C and malondialdehyde with decreased levels of HDL-C, triglycerides, superoxide dismutase, catalase, glutathione and body weights. The pre-treatment of HSP before Cd intoxication prevented the dysregulated activities of liver enzymes and levels of lipid profiles, enzymatic and non-enzymatic antioxidants and other biomarkers investigated, thus suggesting anti-hyperlipidemic and hepato-protective potentials. HSP may have great potentials for development of therapeutics that could enhance the management of dyslipidemia and liver disorders associated with heavy metal exposure.

Therapeutic potential of hesperidin and its aglycone hesperetin: Cell cycle regulation and apoptosis induction in cancer models

BACKGROUND

The ability of cancer cells to divide without restriction and to escape programmed cell death is a feature of the proliferative state. Citrus flavanones are flavonoids with potential multiple anticancer actions, from antioxidant and chemopreventive, to anti-inflammatory, anti-angiogenic, cytostatic and cytotoxic in different cancer models.

PURPOSE

This review aims to summarize the current knowledge on the antiproliferative actions of the citrus flavanones hesperidin (HSD) and hesperetin (HST), with emphasis on cell cycle arrest and apoptosis.

METHODS

Cochrane Library, Scopus, Pubmed and Web of Science collection databases were queried for publications reporting antiproliferative effects of HSD and HST in cancer models.

RESULTS

HSD and HST have been proven to delay cell proliferation in several cancer models. Depending on the compound, dose and cell line studied, different effects have been reported. Cell cycle arrest associated with cytostatic effects has been reported in cells with increased levels of p53 and also cyclin-dependent kinase inhibitors, as well as decreased levels of specific cyclins and cyclin-dependent kinases. Moreover, apoptotic effects have been found to be associated with altered ratios of pro-/antiapoptotic proteins, caspase activation, c-Jun N-terminal kinase (JNK) pathway activation and caspase-independent pathways.

CONCLUSION

Available scientific literature data indicate complex effects, dependent on cell lines and exposure conditions, suggesting that HSD and HST doses need to be optimized according to the cellular and organismal context. The establishment of the main antiproliferative mechanisms is of utmost importance for a possible therapeutic benefit of citrus flavanones in the context of cancer.

Molecular mechanisms of action of hesperidin in cancer: Recent trends and advancements

Hesperidin belongs to flavanones class of flavonoids and is known to possess broad-spectrum applicability to prevent dreadful diseases such as cardiovascular disease, neurodegeneration, and cancer. The reported anticancer effects of hesperidin have been found to be associated with its anti-oxidant and anti-inflammatory activities. Hesperidin interacts with numerous recognized cellular targets and inhibits cancer cell proliferation by inducing apoptosis and cell cycle arrest. In addition, evidence has suggested its promising role in inhibiting tumor cell metastasis, angiogenesis, and chemoresistance. The present mini-review highlights the ongoing development to identify hesperidin targets in cancer. Furthermore, the potential of nano technology-based hesperidin combinations and delivery systems will also be discussed. Overall, this review highlights all the possible molecular targets affected by hesperidin in tumor cells on a single platform.

Impact statement

Experimental findings from numerous studies have demonstrated the anticancer effects of hesperidin (Hesp) to be associated with anti-oxidant and anti-inflammatory activities along with its potential role in inhibiting the tumor cell metastasis and angiogenesis. Additionally, Hesp can also reverse drug resistance of cancer cells, which make it a promising candidate to be used in combination with existing anti-cancer drugs. This review will be helpful for upcoming researchers and scientific community to find out complete capsular package about cancer drug targets of Hesp and its role in modulating various important hallmarks of cancer.

Fabrication of hesperidin nanoparticles loaded by poly lactic co-Glycolic acid for improved therapeutic efficiency and cytotoxicity

Hesperidin, as a flavonone, is recognized as promising anti-inflammatory, antioxidant, and anticancer agent. Its poor bioavailability is crucial bottleneck for therapeutic efficacy. To enhance the stability and bioactive potentials, hesperidin -PLGA-Poloxamer 407 was successfully prepared to minimize or overcome problems associated with hesperidin absorption. The characteristics of nanohesperidin were testing by in vitro dissolution study, XRD, FTIR, PSA and SEM. Antioxidant effects of nanohesperidin were studied. The structure-activity relationship analysis with antioxidant pharmacophore has been performed by using density functional theory method and quantum chemical calculations. The structural properties were investigated using Becke three-parameter hybrid exchange and the Lee-Yang-Parr correction functional methods. Nanohesperidin was found to decrease the H₂O₂ activity-induced DNA instability. Blood compatibility on human erythrocytes was confirmed by haemolytic and in vitro toxicity assessments. The in vitro anticancer activity of nanohesperidin towards MCF-7 cells using various parameters was carried out. The nanohesperidin was found to exert cell growth arrest, activated DNA fragmentation and induced apoptotic cell death through caspase-3 and p53-dependent pathways. These findings showed that nanohesperidin play an important role in its anticancer effects, suggesting might be used for clinical trials and can represent driving formulation for novel chemotherapeutic agents.

Protective Effect of Hesperidin Against Sepsis-Induced Lung Injury by Inducing the Heat-Stable Protein 70 (Hsp70)/Toll-Like Receptor 4 (TLR4)/ Myeloid Differentiation Primary Response 88 (MyD88) Pathway

Background

Sepsis-induced lung injury is associated with high mortality. The present investigation evaluated the protective effect of hesperidin against sepsis-induced lung injury and also postulates the possible mechanism of its action.

Material/Methods

Lung injury was induced by sepsis in all animals, in which sepsis was produced by cecal ligation and puncture (CLP). Animals were treated with hesperidin 10 and 20 mg/kg i.v. 30 min after the surgery. Oxygenation index and lung injury score were determined and levels of pro-inflammatory mediators and markers of oxidative stress were also estimated in the lung tissues. Moreover, expression of caspase-3, B-cell lymphoma (Bcl-2), Toll-like receptor 4 (TLR4), heat-stable protein 70 (Hsp70) and myeloid differentiation primary response 88 (MyD88) protein was estimated by Western blot assay and immunofluorescence assay.

Results

Hesperidin attenuated the partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio and lung injury score in CLP-induced lung injury mice. There was a significant (p<0.01) decrease in the level of pro-inflammatory mediators in the lung tissue of CLP-induced lung injury mice. Moreover, markers of oxidative stress were attenuated in the hesperidin-treated group. Treatment with hesperidin attenuated the expression of caspase-3, Bcl-2, TLR4, Hsp70, and MyD88 protein in the lung tissue of CLP-induced lung injury mice.

Conclusions

Hesperidin protects against lung injury by attenuating the Hsp70/TLR4/MyD88 pathway in CLP-induced lung injury mice.

Novel Lipidized Derivatives of the Bioflavonoid Hesperidin: Dermatological, Cosmetic and Chemopreventive Applications

Hesperidin is one of the most important natural flavonoids, known for its antioxidant, anti-inflammatory, anti-mutagenic, and anti-hypertensive properties. Despite its various biological activities, hesperidin is rarely used in the dermo-cosmetic field because of its poor solubility in both water and oil phases that makes difficult formulation, distribution and bioavailability through the skin layers. Moreover, hesperidin is still underestimated in skin care products, and literature data on its stability into a topical formulation are not yet available. In this paper we report the synthesis of five different derivatives of hesperidin and their evaluation in terms of antioxidant, antifungal, antiproliferative, and apoptotic effects on human leukemic K562 cells. Preliminary antiproliferative effects were considered since hyper-proliferation is involved in several cutaneous problems particularly in the case of photo-exposition and environmental pollution. Esp4 and Esp5 were found to be more active in inhibiting K562 cell growth than parent hesperidin. Esp3 exhibited different biological properties, i.e., antioxidant activity in the absence of antiproliferative effects.

Pharmacoinformatics approach for the identification of Polo-like kinase-1 inhibitors from natural sources as anti-cancer agents

Polo-like kinase-1 (PLK-1) plays a key role in cell cycle progression during mitosis. Overexpression/dysfunction of PLK-1 is directly associated with cancerous transformation and has been reported in different cancer types. Here, we employed high throughput virtual screening and molecular docking to screen Selleck's natural compound library against PLK-1 kinase domain. We have identified eight bioactive compounds (Apigenin, Dihydromyricetin, Diosmetin, Hesperidin, Hesperitin, Naringenin, Phlorizi, and Quercetin) as the potential inhibitors of PLK-1. Further investigation through Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) calculations and 15 ns molecular dynamics simulation revealed that hesperidin formed the most stable complex with PLK-1 kinase domain. Altogether, our results indicate that hesperidin interacted strongly with the key residues of the PLK-1 active site (such as Leu59, Lys61, Lys82, Cys133, Asn181, Asp194, Leu59, Cys67, Ala80, Val114, Leu130, Leu132, Cys133, Leu139, Phe183, and Phe195) through hydrogen bonding and hydrophobic interactions. The Hesperidin-PLK-1 complex was stabilized by Gibb's free energy of -13.235 kcal/mol which corresponded to the binding affinity of 5.095 × 109 M-1. This is the first study wherein hesperidin has been identified as a potential inhibitor of PLK-1. Further design and optimization of the hesperidin scaffold as an inhibitor of PLK-1 kinase domain is highly recommended.

Dihydroartemisinin induced caspase-dependent apoptosis through inhibiting the specificity protein 1 pathway in hepatocellular carcinoma SK-Hep-1 cells

AIMS

Dihydroartemisinin (DHA) is a semi-synthetic derivative of artemisinin, well known for a safe and effective first-line antimalarial agent. This study investigated whether and how DHA induces apoptosis focusing on the specificity protein 1 (Sp1) pathway in hepatocellular carcinoma (HCC) SK-Hep-1 cells.

MAIN METHODS

The cell viability was evaluated by MTT assay. Cell cycle analysis was performed after PI staining by flow cytometry system. Apoptosis was confirmed by DAPI staining and by detecting cytoplasmic histone-associated-DNA-fragments using a cell death detection ELISAPLUS kit. The expression of proteins involved in apoptosis was evaluated by Western blot. The nuclear localization of Sp1 was evaluated by immunofluorescence assay.

KEY FINDINGS

DHA exerted potent cytotoxicity against HCC SK-Hep-1 cells compared with normal hepatocyte AML12 cells. The sub-G1 DNA content and apoptosis index were increased by DHA, which was accompanied by nuclei condensation and fragmentation. DHA activated caspase 3, caspase 8, and caspase 9 and cleaved poly (ADP-ribose) polymerase (PARP). DHA-induced apoptotic cell death, activation of caspases and cleavage of PARP were dramatically inhibited by pan caspase inhibitor Z-VAD-FMK. DHA down-regulated protein expression and nuclear localization of Sp1, which in turn decreased Sp1 downstream target protein, X-linked inhibitor of apoptosis. Decreased Sp1 protein expression by DHA was restored by proteasome inhibitor MG132. DHA led to a down-regulation of phospho-ERK, -p38 and -JNK without affecting their total forms.

SIGNIFICANCE

These results demonstrate that DHA induces caspase-dependent apoptosis in HCC SK-Hep-1 cells by proteasome-dependent degradation of Sp1, which is involved in mitogen-activate protein kinase pathway.

Hesperidin induces apoptosis and G0/G1 arrest in human non-small cell lung cancer A549 cells

Lung cancer has high incidence and mortality rates worldwide. In the present study, the mechanisms by which hesperidin decreases the viability and induces the apoptosis of human non-small cell lung cancer (NSCLC) A549 cells were investigated. Initially, MTT and flow cytometric assays were performed to evaluate the effects of hesperidin on the viability and apoptosis of A549 cells and human normal lung epithelial BEAS-2B cells. The results revealed that hesperidin has no negative effects on the human normal lung epithelial BEAS-2B cells and the viability of cells treated with various concentrations of hesperidin was inhibited in a time- and dose-dependent manner compared with the control groups. Subsequently, the expression levels of proteins involved in the mitochondria-associated apoptotic pathway were studied by western blot analysis. Hesperidin was identified to induce A549 cell apoptosis by downregulating the levels of B-cell lymphoma-2 (Bcl-2) and Bcl extra large protein and simultaneously upregulating the levels of Bcl-2-associated X protein, BH3 interacting-domain death agonist (Bid), tBid, cleaved caspase-9, cleaved caspase-3 and cleaved poly(adenosine diphosphate ribose)polymerase. The effect of hesperidin on the cell cycle was assessed by flow cytometry. Hesperidin was observed to cause G0/G1 arrest of A549 cells by decreasing the expression of cyclin D1 and increasing the expression of p21 and p53. In summary, it was demonstrated that hesperidin induced apoptosis through the mitochondrial apoptotic pathway and induced G0/G1 arrest in human NSCLC A549 cells. Therefore, hesperidin may be developed as a potential therapeutic drug for the treatment of NSCLC.

Health-promoting effects of the citrus flavanone hesperidin

Hesperidin, a member of the flavanone group of flavonoids, can be isolated in large amounts from the rinds of some citrus species. Considering the wide range of pharmacological activities and widespread application of hesperidin, this paper reviews preclinical and clinical trials of hesperidin and its related compounds, including their occurrence, pharmacokinetics, and some marketed products available. Preclinical studies and clinical trials demonstrated therapeutical effects of hesperidin and its aglycone hesperetin in various diseases, such as neurological disorders, psychiatric disorders, and cardiovascular diseases and others, due to its anti-inflammatory, antioxidant, lipid-lowering, and insulin-sensitizing properties.

The Potential Protective Effects of Polyphenols in Asbestos-Mediated Inflammation and Carcinogenesis of Mesothelium

Malignant Mesothelioma (MM) is a tumor of the serous membranes linked to exposure to asbestos. A chronic inflammatory response orchestrated by mesothelial cells contributes to the development and progression of MM. The evidence that: (a) multiple signaling pathways are aberrantly activated in MM cells; (b) asbestos mediated-chronic inflammation has a key role in MM carcinogenesis; (c) the deregulation of the immune system might favor the development of MM; and (d) a drug might have a better efficacy when injected into a serous cavity thus bypassing biotransformation and reaching an effective dose has prompted investigations to evaluate the effects of polyphenols for the therapy and prevention of MM. Dietary polyphenols are able to inhibit cancer cell growth by targeting multiple signaling pathways, reducing inflammation, and modulating immune response. The ability of polyphenols to modulate the production of pro-inflammatory molecules by targeting signaling pathways or ROS might represent a key mechanism to prevent and/or to contrast the development of MM. In this review, we will report the current knowledge on the ability of polyphenols to modulate the immune system and production of mediators of inflammation, thus revealing an important tool in preventing and/or counteracting the growth of MM.

Mitochondrial Dysfunction and Ca(2+) Overload Contributes to Hesperidin Induced Paraptosis in Hepatoblastoma Cells, HepG2

Paraptosis is a programmed cell death which is morphologically and biochemically different from apoptosis. In this study, we have investigated the role of Ca(2+) in hesperidin-induced paraptotic cell death in HepG2 cells. Increase in mitochondrial Ca(2+) level was observed in hesperidin treated HepG2 cells but not in normal liver cancer cells. Inhibition of inositol-1,4,5-triphosphate receptor (IP3 R) and ryanodine receptor also block the mitochondrial Ca(2+) accumulation suggesting that the release of Ca(2+) from the endoplasmic reticulum (ER) may probably lead to the increase in mitochondrial Ca(2+) level. Pretreatment with ruthenium red (RuRed), a Ca(2+) uniporter inhibitor inhibited the hesperidin-induced mitochondrial Ca(2+) overload, swelling of mitochondria, and cell death in HepG2 cells. It has also been demonstrated that mitochondrial Ca(2+) influxes act upstream of ROS and mitochondrial superoxide production. The increased ROS production further leads to mitochondrial membrane loss in hesperidin treated HepG2 cells. Taken together our results show that IP3 R and ryanodine receptor mediated release of Ca(2+) from the ER and its subsequent influx through the uniporter into mitochondria contributes to hesperidin-induced paraptosis in HepG2 cells.

Molecular mechanisms behind the biological effects of hesperidin and hesperetin for the prevention of cancer and cardiovascular diseases

Hesperidin (Hsd) and its aglycone, hesperetin (Hst), are two flavonoids from citrus species that have various biological properties, particularly those for the prevention of cancer and cardiovascular diseases. Studies have shown both anti-cancer and cancer chemopreventive effects for Hsd and Hst. Cancer chemopreventive properties of Hsd and Hst are mainly associated with their antioxidant, radical scavenging and anti-inflammatory activities. In addition, Hsd and Hst interfere at different stages of cancer. Unlike conventional anti-cancer drugs, Hsd and Hst inhibit tumor growth by targeting multiple cellular protein targets at the same time, including caspases, Bcl-2 (B-cell lymphoma 2) and Bax (Bcl-2 associated X protein) for the induction of apoptosis, and COX-2 (cyclooxygenase-2), MMP-2 (matrix metalloproteinase-2) and MMP-9 for the inhibition of angiogenesis and metastasis. The results of the recent basic and clinical studies revealed the beneficial effects for Hst, Hsd and their derivatives in the treatment of heart failure and cardiac remodeling, myocardial ischemia and infarction, and hypertension. In addition, the valuable effects of Hst and Hsd in the treatment of diabetes and dyslipidemia with their anti-platelet and anticoagulant effects make them good candidates in the treatment of various cardiovascular diseases. In this review, new findings regarding the molecular targets of Hsd and Hst, animal studies and clinical trials are discussed.

Licochalcone A, a natural chalconoid isolated from Glycyrrhiza inflata root, induces apoptosis via Sp1 and Sp1 regulatory proteins in oral squamous cell carcinoma

Licochalcone A (LCA), a chalconoid derived from root of Glycyrrhiza inflata, has been known to possess a wide range of biological functions such as antitumor, anti-angiogenesis, antiparasitic, anti-oxidant, antibacterial and anti-inflammatory effects. However, the anticancer effects of LCA on oral squamous cell carcinoma (OSCC) have not been reported. Our data showed that LCA inhibited OSCC cell (HN22 and HSC4) growth in a concentration- and time-dependent manner. Mechanistically, it was mediated via downregulation of specificity protein 1 (Sp1) expression and subsequent regulation of Sp1 downstream proteins such as p27, p21, cyclin D1, Mcl-1 and survivin. Here, we found that LCA caused apoptotic cell death in HSC4 and HN22 cells, as characterized by sub-G1 population, nuclear condensation, Annexin V staining, and multi-caspase activity and apoptotic regulatory proteins such as Bax, Bid, Bcl(-xl), caspase-3 and PARP. Consequently, this study strongly suggests that LCA induces apoptotic cell death of OSCC cells via downregulation of Sp1 expression, prompting its potential use for the treatment of human OSCC.

hesperidin induces paraptosis like cell death in hepatoblastoma, HepG2 Cells: involvement of ERK1/2 MAPK [corrected]

Hesperidin, a natural flavonoid abundantly present in Citrus is known for its anti-cancer, anti-oxidant and anti-inflammatory properties. In this study we examined the effect of hesperidin on HepG2 cells. HepG2 cells treated with various concentration of hesperidin undergo a distinct type of programed cell death. Cytoplasmic vacuolization, mitochondria and endoplasmic reticulum swelling and uncondensed chromatin were observed in hesperidin treated cells. DNA electrophoresis show lack of DNA fragmentation and western blot analysis demonstrates lack of caspase activation and PARP cleavage. It was observed that hesperidin induced cell death is nonautophagic and also activate mitogen activated protein kinase ERK1/2. Taken together, the data indicate that hesperidin induces paraptosis like cell death in HepG2 cells with the activation of ERK1/2. Thus our finding suggests that hesperidin inducing paraptosis may offer an alternative tool in human liver carcinoma therapy.

Gadd45β is transcriptionally activated by p53 via p38α-mediated phosphorylation during myocardial ischemic injury

Growth arrest and DNA damage-inducible 45β (Gadd45β) have been shown to play a role in inducing cardiomyocyte apoptosis under ischemia/anoxia. The well-known transcription factor p53 is known to cause apoptosis in cardiomyocytes under ischemia. Based on the common role of Gadd45β and p53 in ischemia-induced apoptosis, we investigated whether p53 is involved in the mechanisms responsible for Gadd45β expression in both in vitro and in vivo models of ischemic heart injury. A chromatin immunoprecipitation assay revealed direct binding of p53 to the Gadd45β promoter region during anoxia, and this binding was confirmed by surface plasmon resonance imaging. In rat heart-derived H9c2 cells, silencing of p53 abrogated the increase of Gadd45β promoter-luciferase reporter (Gadd45β-Luc) activity and the expression of Gadd45β under anoxia and overexpression of p53 enhanced Gadd45β-Luc activity and Gadd45β expression. Gadd45β mRNA and protein expression were significantly inhibited by p53 siRNA in a rat ischemic heart model. In addition, p38α-mediated phophorylation of p53 at both Ser15 and Ser20 was shown to be essential for the expression of Gadd45β mRNA and protein during anoxia. These results reveal the p38α-p53-Gadd45β axis as a novel signaling module in the anoxia-induced apoptotic death pathway. In conclusion, this study provides molecular evidence that Gadd45β is a novel downstream target gene of p53 under ischemia/anoxia and suggests the therapeutic potential of targeting Gadd45β as a treatment of ischemic heart injury.

KEY MESSAGE

Gadd45β is transcriptionally induced by p53 via direct binding under ischemia/anoxia. The induction of Gadd45β expression requires the p53 phosphorylation at Ser15/Ser20. p38α mediates the p53 phosphorylation at Ser15/Ser20 and the Gadd45β expression. Ischemia/anoxia-p38α-p53-Gadd45β axis serves as a novel apoptotic signaling module.