Robinin modulates doxorubicin-induced cardiac apoptosis by TGF-β1 signaling pathway in Sprague Dawley rats

Robinin protects chondrocytes injury via TLR2/TLR4/NF-κB signaling in osteoarthritis

Osteoarthritis (OA) is a joint disease closely related to aging and characterized by degeneration of articular cartilage. Robinin is a natural agent with various pharmacological properties. Recently, Robinin has been found to have the potential to improve the bone-related diseases. However, its effect on OA development remained unknown. Here, we discuss the specific role and underlying mechanisms of Robinin in interleukin-1beta (IL-1β)-treated chondrocytes and OA mouse model. Chondrocytes were isolated from the mouse to conduct in vitro assays. We evaluated cell viability and apoptosis using Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis, respectively. Western blotting assessed the levels of proteins related to apoptosis, extracellular matrix (ECM), and signaling pathways. Immunofluorescence staining was used to detect the expression of ECM and signaling markers. ELISA was conducted to assess the levels of inflammatory markers. The OA mice model was established using surgical destabilization of the medial meniscus (DMM), and then H&E staining and Safranin O staining were conducted to observe the histopathological changes in synovial tissues. TUNEL assay was used to detect cell apoptosis in vivo. Real-time RT-PCR was operated to measure mRNA level in vitro and in vivo. We discovered that Robinin reversed the IL-1β-induced decrease in chondrocyte viability. Robinin suppressed IL-1β-induced apoptosis of chondrocytes. The ECM destruction and inflammatory response induced by IL-1β were markedly reversed by Robinin incubation in the mouse chondrocytes. Besides, the upregulated cytokine mRNA levels in IL-1β-treated chondrocytes were reduced by Robinin treatment. The downregulation of COL2A1 level and upregulation of MMP13 and ADAMTS5 levels were counteracted by Robinin treatment. Robinin reduced the protein levels of Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4) but enhanced the level of phosphorylated p65 (p-p65) in IL-1β-stimulated chondrocytes and OA mice. Robinin mitigated inflammation, cell apoptosis and cartilage destruction in synovial tissues from the OA mice. In conclusion, Robinin alleviated OA development in vitro and in vivo via TLR2/TLR4/NF-κB signaling pathway.

Doxorubicin-Induced Cardiac Remodeling: Mechanisms and Mitigation Strategies

BACKGROUND

The therapeutic prowess of doxorubicin in oncology is marred by its cardiotoxic consequences, manifesting as cardiac remodeling. Pathophysiological alterations triggered by doxorubicin include inflammatory cascades, fibrotic tissue deposition, vascular and valvular changes, and finally cardiomyopathy. These multifarious consequences collectively orchestrate the deterioration of cardiac architecture and function.

METHOD

By charting the molecular underpinnings and remedial prospects, this review aspires to contribute a novel perspective using latest publications to the ongoing quest for cardioprotection in cancer therapy.

RESULTS AND DISCUSSION

Experimental analyses demonstrate the pivotal roles of oxidative stress and subsequent necrosis and apoptosis of cardiomyocytes, muscle cells, endothelial cells, and small muscle cells in different parts of the heart. In addition, severe and unusual infiltration of macrophages, mast cells, and neutrophils can amplify oxidative damage and subsequent impacts such as chronic inflammatory responses, vascular and valvular remodeling, and fibrosis. These modifications can render cardiomyopathy, ischemia, heart attack, and other disorders. In an endeavor to counteract these ramifications, a spectrum of emerging adjuvants and strategies are poised to fortify the heart against doxorubicin's deleterious effects.

CONCLUSION

The compendium of mitigation tactics such as innovative pharmacological agents hold the potential to attenuate the cardiotoxic burden.

Homotypic targeted nanoplatform enable efficient chemoimmunotherapy and reduced DOX cardiotoxicity in chemoresistant cancer via TGF-β1 blockade

Doxorubicin (DOX) with broad-spectrum antitumor activity has been reported to induce effective immunogenic cell death (ICD) effect. However, the serious cardiotoxicity and chemoresistance severely restrict the widely clinical application of DOX. Herein, for the first time, a bio-inspired nanoplatform via co-assembly of DOX-conjugated polyethyleneimine (PEI-DOX), cancer cell membrane (CCM) and TGF-β1 siRNA (siTGF-β1) was rationally designed, which can not only overcome the drawbacks of DOX but also display high capability to modulate the tumor microenvironment and prevent the tumor progressing and metastasis. Experimental studies confirmed the pH-sensitivity of PEI-DOX and the homotypic-targeting and immuno-escapable ability of CCM, resulting an enhanced accumulation of DOX and siTGF-β1 in tumor sites. In addition to this, the bio-inspired nanoplatform could also improve the stability and facilitate the endosomal escape of siTGF-β1. All these effects ensured the silence efficiency of siTGF-β1 in tumor sites, which could further modulate the chemoresistant and immunosuppressive tumor microenvironment, resulting a synergistic effect with DOX to prevent tumor progressing and metastasis. Additionally, even trapped in cardiac tissues, siTGF-β1 could inhibit the production of TGF-β1 and ROS induced by DOX, resulting a reduced myocardial damage. Therefore, our newly designed bio-inspired nano-delivery system may be a promising nanoplatform with efficient chemoimmunotherapy to ameliorate DOX-induced cardiotoxicity and combat tumor growth and metastasis in chemoresistant cancer.

Mechanism of Action of Flavonoids of Oxytropis falcata on the Alleviation of Myocardial Ischemia–Reperfusion Injury

Oxytropis falcata Bunge is a plant used in traditional Tibetan medicine, with reported anti-inflammatory and antioxidants effects and alleviation of myocardial ischemia reperfusion injury (MIRI). However, the underlying mechanism against MIRI and the phytochemical composition of O. falcata are vague. One fraction named OFF1 with anti-MIRI activity was obtained from O. falcata, and the chemical constituents were identified by ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS). The potential targets and signaling pathways involved in the action of O. falcata against MIRI were predicted by network pharmacology analysis, and its molecular mechanism on MIRI was determined by in vitro assays. The results revealed that flavonoids are the dominant constituents of OFF1. A total of 92 flavonoids reported in O. falcata targeted 213 potential MIRI-associated factors, including tumor necrosis factor (TNF), prostaglandin-endoperoxide synthase 2 (PTGS2), and the NF-κB signaling pathway. The in vitro assay on H9c2 cardiomyocytes subjected to hypoxia/reoxygenation injury confirmed that the flavonoids in OFF1 reduced myocardial marker levels, apoptotic rate, and the inflammatory response triggered by oxidative stress. Moreover, OFF1 attenuated MIRI by downregulating the ROS-mediated JNK/p38MAPK/NF-κB pathway. Collectively, these findings provide novel insights into the molecular mechanism of O. falcata in alleviating MIRI, being a potential therapeutic candidate.

Intestinal fatty acid-binding protein and osteoprotegerin in anthracycline-induced rabbit models of dilated cardiomyopathy

Anthracyclines are used for chemotherapy in small animal cancer patients. However, cardiotoxic complications are very common with anthracycline use and induce multi-organ complications. The purpose of this study was to investigate the associations between multi-organ complications, focusing on the liver and intestine, and the serum concentrations of intestinal fatty acid-binding protein (I-FABP) and osteoprotegerin (OPG) in rabbits with daunorubicin-induced dilated cardiomyopathy (DCM). Sixteen New Zealand white male rabbits (16-20 weeks old), weighing 2.4-3.65 kg, were randomly divided into the control (n = 8) and daunorubicin-induced DCM (n = 8) groups. The concentration of serum I-FABP was significantly elevated in the DCM group (201.9 ± 16.6 pg/mL) compared to the control group (152.2 ± 19.9 g/mL). Additionally, the concentration of serum lactate was markedly increased in the DCM group (0.16 ± 0.01 mM) compared to that in the control group (0.02 ± 0.01 mmol/mL). In addition, the OPG concentration was significantly higher in the DCM group (2.44 ± 0.14 ng/mL) than in the control group (0.1 ± 0.08 ng/mL). Although the histopathology of the ileum did not significantly differ between groups, pathological changes were observed in the livers of the DCM group animals. In conclusion, multi-organ complications were recognized in DCM models and were accompanied by elevated serum I-FABP and OPG concentrations.

A novel RANKL-targeted flavonoid glycoside prevents osteoporosis through inhibiting NFATc1 and reactive oxygen species

BACKGROUND AND PURPOSE

Osteoporosis is characterized by excessive bone resorption due to enhanced osteoclast activation. Stimulation of nuclear factor of activated T cells 1 (NFATc1) and accumulation of reactive oxygen species (ROS) are important mechanisms underlying osteoclastogenesis. Robinin (Rob) is a flavonoid glycoside that has shown anti-inflammatory and antioxidative effects in previous studies, but little is known about its effects on bone homeostasis. The purpose of our research was to investigate whether Rob could prevent bone resorption in ovariectomized (OVX) mice by suppressing osteoclast production through its underlying mechanisms.

METHODS

The docking pose of Rob and RANKL was identified by protein-ligand molecular docking. Rob was added to bone marrow macrophages (BMMs) stimulated by nuclear factor-κB (NF-κB) ligand (RANKL). The effects of Rob on osteoclastic activity were evaluated by positive tartrate resistant acid phosphatase (TRAcP) staining kit and hydroxyapatite resorption assay. RANKL-induced ROS generation in osteoclasts was detected by H2 DCFDA and MitoSox Red staining. The classic molecular cascades triggered by RANKL, such as NF-κB, ROS, calcium oscillations, and NFATc1-mediated signaling pathways, were investigated using Fluo4 staining, western blot, and quantitative real-time polymerase chain reaction. In addition, an OVX mouse model mimicking estrogen-deficient osteoporosis was created to evaluate the therapeutic effects of Rob in vivo.

RESULTS

Computational docking results showed that Rob could bind specifically to RANKL's predicted binding sites. In vitro, Rob inhibited RANKL-mediated osteoclastogenesis dose-dependently without obvious cytotoxicity at low concentrations. We also found that Rob attenuated RANKL-induced mitochondrial ROS production or enhanced activities of ROS-scavenging enzymes, and ultimately reduced intracellular ROS levels. Rob abrogated the RANKL-induced mitogen-activated protein kinase (MAPK) and NF-κB signaling pathways, and subsequently blocked NFATc1 signaling and TRAcP expression. In addition, Rob inhibited osteoclast proliferation by downregulating the expression of osteoclast target genes (Acp5, Cathepsin K, Atp6v0d2, Nfact1, c-Fos, and Mmp9) and reducing Ca2+ oscillations. Our in vivo results showed that Rob reduced bone resorption in OVX animal model by repressing osteoclast activity and function.

CONCLUSIONS

Rob inhibits the activation of osteoclasts by targeting RANKL and is therefore a potential osteoporosis drug.

Bioflavonoid Robinin from Astragalus falcatus Lam. Mildly Improves the Effect of Metothrexate in Rats with Adjuvant Arthritis

Anti-inflammatory potential of orally administrated bioflavonoid-robinin, active sub-stance of original drug Flaroninum™ (FL), was investigated in the combination with methotrexate (MTX) and in monotherapy in rats suffering from adjuvant-induced arthritis (AA). Robinin (kaempferol-3-O-robinoside-7-O-rhamnoside) was isolated from the aerial parts of Astragalus falcatus Lam. The monotherapy with robinin was not efficient in alleviating symptoms of AA. The combination of MTX with robinin was similarly active as MTX alone in reducing the hind paw volume and change of body weight during the whole experiment. The combination, however, reduced plasma levels of Interleukin-17Aand activity of gamma-glutamyl transferase in joint more efficiently then MTX alone. Our results demonstrate that the novel combination of robinin and MTX mildly improved the reduction of inflammation in experimental arthritis.

Pueraria tuberosa: A Review on Traditional Uses, Pharmacology, and Phytochemistry

Pueraria tuberosa (Roxb. ex Willd.) DC. (Fabaceae), also known as Indian Kudzu (vidari kand), is a perennial herb distributed throughout India and other Asian countries. Traditionally, tuber and leaves of this plant have extensively been reported for nutritional and medicinal properties in Ayurveda as well as in Chinese traditional practices. The objective of the present review is to compile and update the published data on traditional uses, pharmacological potential, and phytochemistry of compounds isolated from the plant Pueraria tuberosa. P. tuberosa extracts and its purified compounds possess multiple activities such as anticancer, anticonvulsant, antidiabetic, antifertility, anti-inflammatory, antioxidant, anti-stress, antiulcerogenic, cardioprotective, hypolipidemic, hepatoprotective, immunomodulatory, nephroprotective, nootropic, neuroprotective, and wound healing. Tuber and leaf extracts of P. tuberosa contain several bioactive constituents such as puerarin, daidzein, genistein, quercetin, irisolidone, biochanin A, biochanin B, isoorientin, and mangiferin, which possess an extensive range of pharmacological activities. The extensive range of pharmacological properties of P. tuberosa provides opportunities for further investigation and presents a new approach for the treatment of ailments. Many phytochemicals have been identified and characterized from P. tuberosa; however, some of them are still unexplored, and there is no supporting data for their activities and exact mechanisms of action. Therefore, further investigations are warranted to unravel the mechanisms of action of individual constituents of this plant.

Protection against chemotherapy- and radiotherapy-induced side effects: A review based on the mechanisms and therapeutic opportunities of phytochemicals

BACKGROUND

Although great achievements have been made in the field of cancer therapy, chemotherapy and radiotherapy remain the mainstay cancer therapeutic modalities. However, they are associated with various side effects, including cardiocytotoxicity, nephrotoxicity, myelosuppression, neurotoxicity, hepatotoxicity, gastrointestinal toxicity, mucositis, and alopecia, which severely affect the quality of life of cancer patients. Plants harbor a great chemical diversity and flexible biological properties that are well-compatible with their use as adjuvant therapy in reducing the side effects of cancer therapy.

PURPOSE

This review aimed to comprehensively summarize the molecular mechanisms by which phytochemicals ameliorate the side effects of cancer therapies and their potential clinical applications.

METHODS

We obtained information from PubMed, Science Direct, Web of Science, and Google scholar, and introduced the molecular mechanisms by which chemotherapeutic drugs and irradiation induce toxic side effects. Accordingly, we summarized the underlying mechanisms of representative phytochemicals in reducing these side effects.

RESULTS

Representative phytochemicals exhibit a great potential in reducing the side effects of chemotherapy and radiotherapy due to their broad range of biological activities, including antioxidation, antimutagenesis, anti-inflammation, myeloprotection, and immunomodulation. However, since a majority of the phytochemicals have only been subjected to preclinical studies, clinical trials are imperative to comprehensively evaluate their therapeutic values.

CONCLUSION

This review highlights that phytochemicals have interesting properties in relieving the side effects of chemotherapy and radiotherapy. Future studies are required to explore the clinical benefits of these phytochemicals for exploitation in chemotherapy and radiotherapy.

Natural antioxidants in the vitrification solution improve the ovine ovarian tissue preservation

The present study evaluated the effect of the addition of antioxidants anethole (AN) and robinin (RO) in the vitrification solution, and the in vitro incubation (IVI) medium of ovine ovarian tissue. Ovarian fragments were vitrified without antioxidant (VWA) or with different concentrations of AN (30, 300 and 2000 μg/mL) or RO (0.125, 0.25 and 0.50 mg/mL), followed by IVI (24 h). Histological analyses showed that the percentage of morphologically normal preantral follicles (MNPF) in AN 2000 did not differ from RO 0.125 or fresh ovarian tissue (CTR). Subsequently, ovarian fragments were vitrified in the presence of AN 2000 and RO 0.125 followed by IVI without or with (AN 2000+ and RO 0.125+) the same antioxidants. The follicular activation in all treatments was significantly increased as compared to the CTR. The stroma cell density (SCD) in all the vitrified fragments was significantly lower than the CTR. However, in the AN 2000 and RO 0.125 this parameter was significantly higher when compared to the VWA. The reactive oxygen species (ROS) in the ovarian cortex of the AN 2000 or AN 2000+ were significantly reduced in comparison with the CTR while the intracellular ROS levels of AN 2000 and CTR were similar. The total antioxidant capacity (TAC) in RO 0.125 was significantly higher than that of VWA, AN 2000 and AN 2000+. According to the results, the use of antioxidants (AN or RO) only in the vitrification solution of ovine ovarian tissue is recommended, due to their better preservation of the SCD. Moreover, AN 2000 best maintains the follicular morphology, while RO 0.125 has a high TAC.

Cardioprotective mechanisms of phytochemicals against doxorubicin-induced cardiotoxicity

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

Impact of ethyl pyruvate on Adriamycin-induced cardiomyopathy in rats

Ethyl pyruvate (EP), a derivative of pyruvic acid, is known to have protective effects against ischemic cardiomyopathy and other disorders. However, little is known about its role in Adriamycin (ADR)-induced cardiomyopathy. The present study was designed to investigate the impact of EP on ADR-induced cardiomyopathy in an animal model. Sixty male Sprague-Dawley (SD) rats were divided into four groups: Normal control, EP, ADR and ADR + EP groups (n=15/group). Rats in the ADR and ADR + EP groups were treated with ADR (2.5 mg/kg/week intraperitoneally) for 6 weeks. From the eighth week, rats in the EP and ADR + EP groups received EP via gastric lavage at a dose of 50 mg/kg/day for 30 days. After completing the EP treatment, cardiac function was assessed by echocardiography and then rats were sacrificed. Hearts were harvested for subsequent analysis. Compared with rats in the normal control and EP groups (without ADR treatment), rats in the ADR and ADR + EP groups showed significant impairments in terms of cardiac function, apoptosis, severe oxidative stress and fibrosis in the heart. However, these impairments were alleviated by EP treatment in the ADR + EP group. Upon EP treatment, cardiac function was significantly improved. The levels of oxidative stress, fibrosis and apoptosis in the myocardial tissues were also significantly reduced. These findings indicated that EP treatment attenuated, at least partially, ADR-induced cardiomyopathy in rats.

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

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

AST IV inhibits H₂O₂-induced human umbilical vein endothelial cell apoptosis by suppressing Nox4 expression through the TGF-β1/Smad2 pathway

Endothelial cell apoptosis plays an important role in the pathophysiological mechanisms of vascular complications in diabetes mellitus (DM). NADPH oxidase 4 (Nox4)-dependent reactive oxygen species (ROS) aggregation is the main cause of vascular endothelial cell apoptosis. The transforming growth factor-β1 (TGF-β1)/Smad2 signaling pathway is involved in the apoptosis of several types of cells. However, the association between vascular endothelial cell apoptosis and Nox4, and the involvement of the TGF-β1/Smad2 signaling pathway in vascular endothelial cell apoptosis remain unclear. In the present study, we aimed to investigate the role of Nox4-dependent ROS production and to determine the involvement of the TGF-β1/Smad2 signaling pathway in endothelial cell apoptosis induced by oxidative stress which causes vascular injury in DM. We demonstrated that hydrogen peroxide (H2O2) increased Nox4-dependent-ROS aggregation, as well as the expression of TGF-β1, Smad2, Bax and caspase-3, decreased Bcl-2 expression and increased the apoptosis of human umbilical vein endothelial cells (HUVECs). Treatment with diphenyliodonium (DPI), a specific inhibitor of Nox4 or astragaloside IV (AST IV), a monomer located in an extract of astragaloside, decreased Nox4 expression and the levels of ROS, decreased TGF-β1 and Smad2 expression, altered the expression of apoptosis-related genes and decreased the apoptosis of HUVECs. Treatment with LY2109761, a selective inhibitor of the TGF-β1/Smad2 pathway, produced results similar to those of DPI; however, LY2109761 had no effect on Nox4 expression and ROS levels. Taken together, the findings of the present study suggest that H2O2 contributes to HUVEC apoptosis by inducing Nox4-dependent ROS aggregation and activating the TGF-β1/Smad2 signaling pathway. Our data indicate that the protective effects of AST IV against vascular endothelial cell apoptosis in DM are mainly associated with the decrease in Nox4 expression through the TGF-β1/Smad2 signaling pathway. Furthermore, the inhibition of the activation of the TGF-β1/Smad2 signaling pathway may be another potential therapeutic strategy in the treatment of DM.