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Kam MK, Park JY, Yun GH, Sohn HY, Park JH, Choi J, Koh YH, Jo C. Rottlerin Enhances the Autophagic Degradation of Phosphorylated Tau in Neuronal Cells. Mol Neurobiol 2024:10.1007/s12035-024-04182-9. [PMID: 38671330 DOI: 10.1007/s12035-024-04182-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 04/15/2024] [Indexed: 04/28/2024]
Abstract
Intra-neuronal accumulation of hyper-phosphorylated tau as neurofibrillary tangles (NFT) is a hallmark of Alzheimer's disease (AD). To prevent the aggregation of phosphorylated tau in neurons, decreasing the phosphorylated tau protein levels is important. Here, we examined the biological effects of rottlerin, a phytochemical compound extracted from the Kamala tree, Mallotus philippinensis, on phosphorylated tau levels. Notably, rottlerin decreased the levels of intracellular phosphorylated and total tau. A marked increase in the LC3-II, a hallmark of autophagy, was observed in these cells, indicating that rottlerin strongly induced autophagy. Interestingly, rottlerin induced the phosphorylation of Raptor at S792 through the activation of adenosine-monophosphate activated-protein kinase (AMPK), which likely inhibits the mammalian target of rapamycin complex 1 (mTORC1), thus resulting in the activation of transcription factor EB (TFEB), a master regulator of autophagy. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) activity increased in the presence of rottlerin. The decrease of phosphorylated tau levels in the presence of rottlerin was ameliorated by the knockdown of TFEB and partially attenuated by the knockout of the Nrf2 gene. Taken together, rottlerin likely enhances the degradation of phosphorylated tau through autophagy activated by TFEB and Nrf2. Thus, our results suggest that a natural compound rottlerin could be used as a preventive and therapeutic drug for AD.
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Affiliation(s)
- Min Kyoung Kam
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Jee-Yun Park
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Gwang Ho Yun
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Hee-Young Sohn
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Jung Hyun Park
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Jiyoung Choi
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Young Ho Koh
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea
| | - Chulman Jo
- Division of Brain Disease Research, Department for Chronic Disease Convergence Research, Korea National Institute of Health, 187 Osongsaengmyeong2-Ro, Osong-Eup, Cheongju-Si, 363-951, Chungcheongbuk-Do, Korea.
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Erdogan MA, Yılmaz OA. Rottlerin and genistein inhibit neuroblastoma cell proliferation and invasion through EF2K suppression and related protein pathways. Naunyn Schmiedebergs Arch Pharmacol 2023; 396:2481-2500. [PMID: 37083712 DOI: 10.1007/s00210-023-02473-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 03/21/2023] [Indexed: 04/22/2023]
Abstract
Neuroblastoma is one of the most common solid tumors in children younger than 1 year of age, with poor prognosis and survival rates. Therefore, novel molecular targets and therapeutic strategies are needed to prolong patient survival. For this purpose, we investigated the effects of rottlerin and genistein separately and in combination on neuroblastoma cells (SH-SY5Y, Kelly). First, the effects of rottlerin and genistein were investigated on cell proliferation. Different rottlerin (1-50 µM) and genistein (5-150 µM) doses were used as experimental groups compared to the control (DMSO/vehicle). The IC50 dose was found to be 5 µM for rottlerin and 30 µM for genistein (P < 0.0001). Other analyses, such as colony formation assays, annexin V/propidium iodide staining, matrigel invasion assays, and Western blot analysis, were performed with these doses and their combinations. To assess statistical significance, statistical analysis was conducted using the one-way ANOVA with the post hoc Tukey test. Our results showed that IC50 doses of rottlerin and genistein induced a significant reduction in cell proliferation, colony formation, and invasion in neuroblastoma cells (P < 0.0001). The combination of these doses increased the levels of inhibition of cell proliferation and invasion while decreasing the level of apoptosis (P 0.0001). Furthermore, these agents caused G1-cell cycle arrest in these cells. Our western blot data showed that rottlerin and genistein treatments markedly inhibit elongation factor 2 kinase (EF2K) and other pro-tumorigenic, metastatic proteins in neuroblastoma cells. These agents probably showed their anti-proliferative, anti-metastatic, and pro-apoptotic effects through EF2K downregulation. Our results suggested that rottlerin and genistein have inhibitory effects on cancer cell proliferation, invasion, and cell cycle and induce apoptosis in both cell lines. Combined treatment with rottlerin and genistein may be a viable approach and beneficial to neuroblastoma patients as the combined effect significantly suppresses the above-mentioned pathways.
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Affiliation(s)
- Mumin Alper Erdogan
- Department of Physiology, Faculty of Medicine, Izmir Katip Celebi University, Izmir, Turkey.
- Faculty of Medicine, Department of Physiology, Ege University, Izmir, Turkey.
| | - Ozlem Alkan Yılmaz
- Faculty of Medicine, Department of Physiology, Ege University, Izmir, Turkey
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Teixeira SC, Paschoalino M, de Souza G, Rosini AM, de Lima Junior JP, Luz LC, Fajardo Martínez AF, Alves RN, Almeida MPO, Damasceno JL, Silva MJB, Ietta F, Barbosa BF, Ferro EAV, Gomes Martins CH. Rottlerin impairs early and late steps of Toxoplasma gondii infection in human trophoblast cells and villous explants. Chem Biol Interact 2023; 384:110716. [PMID: 37722575 DOI: 10.1016/j.cbi.2023.110716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/04/2023] [Accepted: 09/15/2023] [Indexed: 09/20/2023]
Abstract
Congenital toxoplasmosis, caused by the opportunistic protozoan parasite T. gondii, can cause stillbirths, miscarriages and fetal abnormalities, as well as encephalitis and chorioretinitis in newborns. Available treatment options rely on antiparasitic drugs that have been linked to serious side effects, high toxicity and the development of drug-resistant parasites. The search for alternative therapeutics to treat this disease without acute toxicity for the mother and child is essential for the advancement of current therapeutic procedures. The present study aimed to unravel the mode of the anti-T. gondii action of Rottlerin, a natural polyphenol with multiple pharmacological properties described. Herein, we further assessed the antiparasitic activity of Rottlerin against T. gondii infection on the human trophoblastic cells (BeWo cells) and, for the first time, on human villous explants. We found that non-cytotoxic doses of Rottlerin impaired early and late steps of parasite infection with an irreversible manner in BeWo cells. Rottlerin caused parasite cell cycle arrest in G1 phase and compromised the ability of tachyzoites to infect new cells, thus highlighting the possible direct action on parasites. An additional and non-exclusive mechanism of action of Rottlerin involves the modulation of host cell components, by affecting lipid droplet formation, mitochondrial function and upregulation of the IL-6 and MIF levels in BeWo cells. Supporting our findings, Rottlerin also controlled T. gondii proliferation in villous explants with low toxicity and reduced the IL-10 levels, a cytokine associated with parasite susceptibility. Collectively, our results highlighted the potential use of Rottlerin as a promising tool to prevent and/or treat congenital toxoplasmosis.
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Affiliation(s)
- Samuel Cota Teixeira
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Marina Paschoalino
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Guilherme de Souza
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Alessandra Monteiro Rosini
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Joed Pires de Lima Junior
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Luana Carvalho Luz
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Aryani Felixa Fajardo Martínez
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Rosiane Nascimento Alves
- Department of Agricultural and Natural Sciences, Universidade do Estado de Minas Gerais, Ituiutaba, MG, Brazil
| | - Marcos Paulo Oliveira Almeida
- Laboratory of Immunopathology, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Jaqueline Lopes Damasceno
- Laboratory of Antimicrobial Testing, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Marcelo José Barbosa Silva
- Department of Immunology, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Francesca Ietta
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Bellisa Freitas Barbosa
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Eloisa Amália Vieira Ferro
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
| | - Carlos Henrique Gomes Martins
- Laboratory of Antimicrobial Testing, Institute of Biomedical Sciences, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
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Ojha D, Jessop F, Bosio CM, Peterson KE. Effective inhibition of HCoV-OC43 and SARS-CoV-2 by phytochemicals in vitro and in vivo. Int J Antimicrob Agents 2023; 62:106893. [PMID: 37339711 PMCID: PMC10277159 DOI: 10.1016/j.ijantimicag.2023.106893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 05/26/2023] [Accepted: 06/14/2023] [Indexed: 06/22/2023]
Abstract
OBJECTIVE Several coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and human coronavirus OC43 (HCoV-OC43), can cause respiratory infections in humans. To address the need for reliable anti-coronavirus therapeutics, we screened 16 active phytochemicals selected from medicinal plants used in traditional applications for respiratory-related illnesses. METHODS An initial screen was completed using HCoV-OC43 to identify compounds that inhibit virus-induced cytopathic effect (CPE) and cell death inhibition. Then the top hits were validated in vitro against both HCoV-OC43 and SARS-CoV-2 by determining virus titer in cell supernatant and virus-induced cell death. Finally, the most active phytochemical was validated in vivo in the SARS-CoV-2-infected B6.Cg-Tg(K18-ACE2)2Prlmn/J mouse model. RESULTS The phytochemicals lycorine (LYC), capsaicin, rottlerin (RTL), piperine and chebulinic acid (CHU) inhibited HCoV-OC43-induced cytopathic effect and reduced viral titres by up to 4 log. LYC, RTL and CHU also suppressed virus replication and cell death following SARS-CoV-2 infection. In vivo, RTL significantly reduced SARS-CoV-2-induced mortality by ∼40% in human angiotensin-converting enzyme 2 (ACE2)-expressing K18 mice. CONCLUSION Collectively, these studies indicate that RTL and other phytochemicals have therapeutic potential to reduce SARS-CoV-2 and HCoV-OC43 infections.
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Affiliation(s)
- Durbadal Ojha
- Neuroimmunology Section, Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 S. 4th St., Hamilton, MT, USA.
| | - Forrest Jessop
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 S. 4th St., Hamilton, MT, USA
| | - Catharine M Bosio
- Immunity to Pulmonary Pathogens Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 S. 4th St., Hamilton, MT, USA
| | - Karin E Peterson
- Neuroimmunology Section, Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 S. 4th St., Hamilton, MT, USA.
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Kim Y, Kim HK, Kang S, Kim H, Go GW. Rottlerin suppresses lipid accumulation by inhibiting de novo lipogenesis and adipogenesis via LRP6/mTOR/SREBP1C in 3T3-L1 adipocytes. Food Sci Biotechnol 2023; 32:1445-1452. [PMID: 37457404 PMCID: PMC10349001 DOI: 10.1007/s10068-023-01339-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/24/2023] [Accepted: 05/12/2023] [Indexed: 07/18/2023] Open
Abstract
Rottlerin is isolated from Mallotus japonicus, a plant rich in polyphenols. Rottlerin is a selective PKCδ-inhibitor and is also known as an uncoupler of oxidative phosphorylation and anti-neoplastic agent. However, its anti-obesity effect is yet to be established. Therefore, this study tested whether rottlerin inhibits adipogenesis and de novo lipogenesis via the LRP6/mTOR/SREBP1C pathway in 3T3-L1 adipocytes. Rottlerin dramatically decreased lipid accumulation assessed by Oil Red O as evidence to support the cellular phenotype (p < 0.001). Pivotal messenger RNA and protein expressions associated with de novo lipogenesis (SREBP1C, ACC1, FAS, and SCD1) and adipogenesis (PPARγ and C/EBPα) were subsequentially verified by rottlerin in a dose-dependent manner (p < 0.05). Further investigation revealed that rottlerin reduced the AKT/mTOR pathway via diminished total protein of LRP6 (p < 0.05). Collectively, these findings establish a causal link between rottlerin, LRP6, and the altered nutrient-sensing mTOR pathway, in which rottlerin regulates de novo lipogenesis and adipogenesis in white adipocytes.
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Affiliation(s)
- Yejin Kim
- Department of Food and Nutrition, Hanyang University, Seoul, 04763 Republic of Korea
| | - Hyun Kyung Kim
- Department of Food and Nutrition, Hanyang University, Seoul, 04763 Republic of Korea
| | - Sumin Kang
- Department of Food and Nutrition, Hanyang University, Seoul, 04763 Republic of Korea
| | - Hayoon Kim
- Department of Food and Nutrition, Hanyang University, Seoul, 04763 Republic of Korea
| | - Gwang-woong Go
- Department of Food and Nutrition, Hanyang University, Seoul, 04763 Republic of Korea
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Manhas D, Bhatt S, Rai G, Kumar V, Bharti S, Dhiman S, Jain SK, Sharma DK, Ojha PK, Gandhi SG, Goswami A, Nandi U. Rottlerin renders a selective and highly potent CYP2C8 inhibition to impede EET formation for implication in cancer therapy. Chem Biol Interact 2023; 380:110524. [PMID: 37146929 DOI: 10.1016/j.cbi.2023.110524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/14/2023] [Accepted: 05/03/2023] [Indexed: 05/07/2023]
Abstract
CYP2C8 is a crucial CYP isoform responsible for the metabolism of xenobiotics and endogenous molecules. CYP2C8 converts arachidonic acid to epoxyeicosatrienoic acids (EETs) that cause cancer progression. Rottlerin possess significant anticancer actions. However, information on its CYP inhibitory action is lacking in the literature and therefore, we aimed to explore the same using in silico, in vitro, and in vivo approaches. Rottlerin showed highly potent and selective CYP2C8 inhibition (IC50 < 0.1 μM) compared to negligible inhibition (IC50 > 10 μM) for seven other experimental CYPs in human liver microsomes (HLM) (in vitro) using USFDA recommended index reactions. Mechanistic studies reveal that rottlerin could reversibly (mixed-type) block CYP2C8. Molecular docking (in silico) results indicate a strong interaction could occur between rottlerin and the active site of human CYP2C8. Rottlerin boosted the plasma exposure of repaglinide and paclitaxel (CYP2C8 substrates) by delaying their metabolism using the rat model (in vivo). Multiple-dose treatment of rottlerin with CYP2C8 substrates lowered the CYP2C8 protein expression and up-regulated & down-regulated the mRNA for CYP2C12 and CYP2C11 (rat homologs), respectively, in rat liver tissue. Rottlerin substantially hindered the EET formation in HLM. Overall results of rottlerin on CYP2C8 inhibition and EET formation insinuate further exploration for targeted cancer therapy.
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Affiliation(s)
- Diksha Manhas
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Shipra Bhatt
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Garima Rai
- Infectious Diseases Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India
| | - Vinay Kumar
- Drug Theoretics and Chemoinformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700032, India
| | - Sahil Bharti
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Sumit Dhiman
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India
| | - Shreyans K Jain
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Deepak K Sharma
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Probir Kumar Ojha
- Drug Theoretics and Chemoinformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700032, India
| | - Sumit G Gandhi
- Infectious Diseases Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Anindya Goswami
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Utpal Nandi
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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Manhas D, Mir KB, Tripathi N, Bharti S, Dhiman S, Wazir P, Sharma DK, Goswami A, Nandi U. Rottlerin promotes anti-metastatic events by ameliorating pharmacological parameters of paclitaxel: An in-vivo investigation in the orthotopic mouse model of breast cancer. Chem Biol Interact 2022; 366:110109. [PMID: 35995259 DOI: 10.1016/j.cbi.2022.110109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 02/07/2023]
Abstract
Despite substantial breakthroughs in cancer research, there is hardly any specific therapy available to date that can alleviate triple-negative breast cancer (TNBC). Paclitaxel is the first-line chemotherapy option, but its treatment is often associated with early discontinuation of therapy due to the development of resistance and/or precipitation of severe side effects. In the quest to establish a suitable combination therapy with a low dose of paclitaxel, we explored rottlerin (a pure and characterized phytoconstituent from Mallotus philippensis) because of its multifaceted pharmacological actions against cancer. The study was performed to assess the therapeutic effects of rottlerin (5-20 mg/kg) with a low dose of paclitaxel (5 mg/kg) using a highly aggressive mouse mammary carcinoma model. Rottlerin augmented the paclitaxel effect by reducing tumor burden as well as metastatic lung nodules formation. Rottlerin in combination with paclitaxel remarkably altered the expression of vital epithelial-mesenchymal transition (EMT) markers such as E-cadherin, Snail 1, & Vimentin and thus improved the anti-metastatic efficacy of paclitaxel. Significant attenuation of anti-apoptotic protein (Bcl-2) along with amplification of pro-apoptotic (cleaved PARP) marker confers that rottlerin could ameliorate the pro-apoptotic potential of paclitaxel. In this study, a rational combination of rottlerin and paclitaxel treatment curtailed CYP2J2 expression and epoxyeicosatrienoic acids (EETs) levels, responsible for restrain tumor growth and metastasis. Additionally, rottlerin lessened paclitaxel treatment-mediated hematological alterations and prevented paclitaxel treatment-linked key serum biochemical changes related to organ toxicities. These rottlerin treatment-mediated protective changes are closely associated with the lower paclitaxel accumulation in the corresponding tissues. Rottlerin caused significant pharmacokinetic interaction with paclitaxel to boost the plasma level of paclitaxel in a typical mouse model and possibly helpful towards the use of a low dose of paclitaxel in combination. Overall, it can be stated that rottlerin has significant potential to augment the anti-metastatic efficacy of paclitaxel via impeding EMT activation along with attenuating its treatment-associated toxicological alterations. Hence, rottlerin has significant potential to explore further as a suitable neoadjuvant therapy with paclitaxel against TNBC.
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Hwang Y, Kim HC, Shin EJ. Effect of rottlerin on astrocyte phenotype polarization after trimethyltin insult in the dentate gyrus of mice. J Neuroinflammation 2022; 19:142. [PMID: 35690821 PMCID: PMC9188234 DOI: 10.1186/s12974-022-02507-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 06/01/2022] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND It has been demonstrated that reactive astrocytes can be polarized into pro-inflammatory A1 phenotype or anti-inflammatory A2 phenotype under neurotoxic and neurodegenerative conditions. Microglia have been suggested to play a critical role in astrocyte phenotype polarization by releasing pro- and anti-inflammatory mediators. In this study, we examined whether trimethyltin (TMT) insult can induce astrocyte polarization in the dentate gyrus of mice, and whether protein kinase Cδ (PKCδ) plays a role in TMT-induced astrocyte phenotype polarization. METHODS Male C57BL/6 N mice received TMT (2.6 mg/kg, i.p.), and temporal changes in the mRNA expression of A1 and A2 phenotype markers were evaluated in the hippocampus. In addition, temporal and spatial changes in the protein expression of C3, S100A10, Iba-1, and p-PKCδ were examined in the dentate gyrus. Rottlerin (5 mg/kg, i.p. × 5 at 12-h intervals) was administered 3-5 days after TMT treatment, and the expression of A1 and A2 transcripts, p-PKCδ, Iba-1, C3, S100A10, and C1q was evaluated 6 days after TMT treatment. RESULTS TMT treatment significantly increased the mRNA expression of A1 and A2 phenotype markers, and the increased expression of A1 markers remained longer than that of A2 markers. The immunoreactivity of the representative A1 phenotype marker, C3 and A2 phenotype marker, S100A10 peaked 6 days after TMT insult in the dentate gyrus. While C3 was expressed evenly throughout the dentate gyrus, S100A10 was highly expressed in the hilus and inner molecular layer. In addition, TMT insult induced microglial p-PKCδ expression. Treatment with rottlerin, a PKCδ inhibitor, decreased Iba-1 and C3 expression, but did not affect S100A10 expression, suggesting that PKCδ inhibition attenuates microglial activation and A1 astrocyte phenotype polarization. Consistently, rottlerin significantly reduced the expression of C1q and tumor necrosis factor-α (TNFα), which has been suggested to be released by activated microglia and induce A1 astrocyte polarization. CONCLUSION We demonstrated the temporal and spatial profiles of astrocyte polarization after TMT insult in the dentate gyrus of mice. Taken together, our results suggest that PKCδ plays a role in inducing A1 astrocyte polarization by promoting microglial activation and consequently increasing the expression of pro-inflammatory mediators after TMT insult.
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Affiliation(s)
- Yeonggwang Hwang
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chuncheon, 24341, Republic of Korea.
| | - Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chuncheon, 24341, Republic of Korea.
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Kang YL, Oh C, Ahn SH, Choi JC, Choi HY, Lee SW, Choi IS, Song CS, Lee JB, Park SY. Inhibition of endocytosis of porcine reproductive and respiratory syndrome virus by rottlerin and its potential prophylactic administration in piglets. Antiviral Res 2021; 195:105191. [PMID: 34678331 DOI: 10.1016/j.antiviral.2021.105191] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 08/27/2021] [Accepted: 10/18/2021] [Indexed: 02/07/2023]
Abstract
Owing to several limitations of porcine reproductive and respiratory syndrome virus (PRRSV) control procedures, the importance of antiviral agents is increasing; however, limited studies have been done on the development of anti-PRRSV agents. Herein, we explored the antiviral effect and mechanism of rottlerin against PRRSV. We demonstrated that treatment of rottlerin at an early stage of PRRSV infection significantly inhibited the viral replication. PRRSV infection induced protein kinase C-δ phosphorylation, which was specifically downregulated by rottlerin. The treatment of rottlerin led to disrupting the PRRSV entry pathway by blocking endocytosis of the virions. Further, to evaluate the anti-PRRSV effect of the rottlerin in vivo, we administrated rottlerin loaded liposome to pigs infected with PRRSV LMY or FL12 strain. The treatment of rottlerin-liposome reduced the blood viral load, interstitial pneumonia and clinical scores compared to untreated pigs. These results provide an evidence of anti-PRRSV effect of rottlerin in vitro via inhibiting PRRSV internalization and in vivo, all of which strongly suggest the applicability of rottlerin as a potential PRRSV prophylactic treatment.
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Huang WL, Hsiung MH, Dai W, Hu SSJ. Rottlerin, BDNF, and the impairment of inhibitory avoidance memory. Psychopharmacology (Berl) 2021; 238:421-439. [PMID: 33146738 DOI: 10.1007/s00213-020-05690-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 10/23/2020] [Indexed: 02/07/2023]
Abstract
RATIONALE AND OBJECTIVE As a eukaryotic elongation factor 2 kinase (eEF2K) inhibitor and a mitochondrial uncoupler, oncologists have extensively studied rottlerin. Neuroscientists, however, have accumulated scarce data on the role of rottlerin in affective and cognitive functions. Only two prior studies have, respectively, documented its antidepressant-like effect and how it impairs psychostimulant-supported memory. Whether or not rottlerin would affect aversive memory remains unknown. Hence, we sought to investigate the effects of rottlerin on aversive memory in the inhibitory avoidance (IA) task in mice. MATERIALS AND METHODS Male C57BL/6J mice were trained to acquire the IA task. Rottlerin (5 mg/kg, i.p. or 3 μg bilaterally in the hippocampus) or the vehicle was administered before footshock training (acquisition), after footshock training (consolidation), after the memory reactivation (reconsolidation), and before the test (retrieval) in the IA task. RESULTS Systemic and intrahippocampal rottlerin impaired the acquisition, consolidation, and retrieval of IA memory, without affecting the reconsolidation process. Rottlerin (5 mg/kg, i.p.) induced a fast-onset and long-lasting increase in the brain-derived neurotrophic factor (BDNF) protein levels in the mouse hippocampus. Systemic injection of 7,8-dihydroxyflavone (7,8-DHF, 30 mg/kg), a BDNF tropomyosin receptor kinase B (TrkB) agonist impaired IA memory consolidation, and treatment with K252a (5 μg/kg), a Trk receptor antagonist, reversed the suppressing effect of rottlerin on IA memory consolidation. CONCLUSION Rottlerin impairs IA memory consolidation through the enhancement of BDNF signaling in the mouse hippocampus. Excessive brain BDNF levels can be detrimental to cognitive function. Rottlerin is likely to affect the original memory-associated neuroplasticity. Thus, it can be combined with exposure therapy to facilitate the forgetting of maladaptive aversive memory, such as post-traumatic stress disorder (PTSD).
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Affiliation(s)
- Wan-Ling Huang
- Cannabinoid Signaling Laboratory, Department of Psychology, National Cheng Kung University, 1 University Rd, Tainan, 70101, Taiwan
| | - Ming-Heng Hsiung
- Cannabinoid Signaling Laboratory, Department of Psychology, National Cheng Kung University, 1 University Rd, Tainan, 70101, Taiwan
| | - Wen Dai
- Cannabinoid Signaling Laboratory, Department of Psychology, National Cheng Kung University, 1 University Rd, Tainan, 70101, Taiwan
| | - Sherry Shu-Jung Hu
- Cannabinoid Signaling Laboratory, Department of Psychology, National Cheng Kung University, 1 University Rd, Tainan, 70101, Taiwan.
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Lee TH, Chen JL, Liu PS, Tsai MM, Wang SJ, Hsieh HL. Rottlerin, a natural polyphenol compound, inhibits upregulation of matrix metalloproteinase-9 and brain astrocytic migration by reducing PKC-δ-dependent ROS signal. J Neuroinflammation 2020; 17:177. [PMID: 32505192 PMCID: PMC7276071 DOI: 10.1186/s12974-020-01859-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 05/29/2020] [Indexed: 02/07/2023] Open
Abstract
Background Upregulation of matrix metalloproteinase-9 (MMP-9) has been indicated as one of the inflammatory biomarkers. In the central nervous system (CNS), the MMP-9 is induced by several proinflammatory mediators and participates in the CNS disorders, including inflammation and neurodegeneration. In addition, protein kinase Cs (PKCs) has been shown to be involved in regulation of various inflammatory factors like MMP-9 by several stimuli in many cell types. Several phytochemicals are believed to reduce the risk of several inflammatory disorders including the CNS diseases. The rottlerin, a principal phenolic compound of the Kamala plant Mallotus philippinensis, has been shown to possess an array of medicinal properties, including anti-PKC-δ, antitumor, anti-oxidative, and anti-inflammatory activities. Methods Herein, we used rat brain astrocytes (RBA) to demonstrate the signaling mechanisms of phorbol 12-myristate 13-acetate (PMA)-induced MMP-9 expression by zymographic, RT-PCR, subcellular isolation, Western blot, ROS detection, and promoter reporter analyses. Then, we evaluate the effects of rottlerin on PMA-induced MMP-9 expression in RBA and its influencing mechanism. Results We first demonstrated that PMA stimulated activation of various types of PKC, including PKC-δ in RBA. Subsequently, PMA induced MMP-9 expression via PKCδ-mediated reactive oxygen species (ROS) generation, extracellular signal-regulated kinase 1/2 (ERK1/2) activation, and then induced c-Fos/AP-1 signaling pathway. Finally, upregulation of MMP-9 by PMA via the pathway may promote astrocytic migration, and the event could be attenuated by rottlerin. Conclusions These data indicated that rottlerin may have anti-inflammatory activity by reducing these related pathways of PKC-δ-dependent ROS-mediated MMP-9 expression in brain astrocytes.
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Affiliation(s)
- Tsong-Hai Lee
- Stroke Center and Stroke Section, Department of Neurology, College of Medicine, Chang Gung Memorial Hospital, Linkou Medical Center and Chang Gung University, Taoyuan, Taiwan
| | - Jiun-Liang Chen
- Division of Chinese Internal Medicine, Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital and School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Pei-Shan Liu
- Department of Microbiology, Soochow University, Taipei, Taiwan
| | - Ming-Ming Tsai
- Department of Nursing, Division of Basic Medical Sciences, Research Center for Chinese Herbal Medicine, and Graduate Institute of Health Industry Technology, Chang Gung University of Science and Technology, 261 Wenhua 1st Road, Guishan, Taoyuan, Taiwan.,Department of General Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Su-Jane Wang
- School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Hsi-Lung Hsieh
- Department of Nursing, Division of Basic Medical Sciences, Research Center for Chinese Herbal Medicine, and Graduate Institute of Health Industry Technology, Chang Gung University of Science and Technology, 261 Wenhua 1st Road, Guishan, Taoyuan, Taiwan. .,Department of Neurology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
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12
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Zhu J, Wang Y, Hu Q, Yuan R, Ye J. Rottlerin acts as a therapeutic in primary open-angle glaucoma by targeting the trabecular meshwork via activation of Rap1 signaling. Pharmacol Res 2020; 159:104780. [PMID: 32360586 DOI: 10.1016/j.phrs.2020.104780] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 02/07/2023]
Abstract
Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness worldwide, and elevated intraocular pressure (IOP) is a major risk factor. While IOP is mainly controlled by adjusting the outflow resistance in the trabecular meshwork (TM), drugs that act directly on the TM are rare. In this study, we discovered a novel compound and pathway that acts on the TM and decreases IOP by genomic, proteomic, and bioinformatic analyses of POAG-derived TMs and experimental validation. Overlapping differentially expressed genes of the TM between patients with POAG and normal controls from two independent gene expression profiles in public databases were analyzed and matched by using the Connectivity Map (CMap). Rottlerin was identified as a potential compound. Subsequent experiments confirmed that rottlerin reversed POAG phenotypes in vitro and that it decreased IOP and actin/extracellular matrix accumulation in vivo with no detectable ocular side effects. SwissTargetPrediction in combination with pathway analysis predicted that the effects of rottlerin may be mediated by activation of the Rap1 pathway. Finally, we confirmed that rottlerin upregulated Rap1 and the downstream PI3K/AKT pathway independent of the MAPK/ERK pathway in a dexamethasone-induced POAG cell model.
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Lama Z, Gaudin Y, Blondel D, Lagaudrière-Gesbert C. Kinase inhibitors tyrphostin 9 and rottlerin block early steps of rabies virus cycle. Antiviral Res 2019; 168:51-60. [PMID: 31071352 DOI: 10.1016/j.antiviral.2019.04.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/07/2019] [Accepted: 04/29/2019] [Indexed: 11/26/2022]
Abstract
Rabies virus (RABV) is a neurotropic virus that causes fatal encephalitis in humans and animals and still kills up to 59,000 people worldwide every year. To date, only preventive or post-exposure vaccination protects against the disease but therapeutics are missing. After screening a library of 80 kinases inhibitors, we identified two compounds as potent inhibitors of RABV infection: tyrphostin 9 and rottlerin. Mechanism of action studies show that both inhibitors interfere with an early step of viral cycle and can prevent viral replication. In presence of tyrphostin 9, the viral entry through endocytosis is disturbed leading to improper delivery of viral particles in cytoplasm, whereas rottlerin is inhibiting the transcription, most likely by decreasing intracellular ATP concentration, and therefore the replication of the viral genome.
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Affiliation(s)
- Zoé Lama
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Yves Gaudin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Danielle Blondel
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France
| | - Cécile Lagaudrière-Gesbert
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette cedex, France.
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Abstract
Rottlerin as a natural agent, which is isolated from Mallotus philippinensis, has been identified to play a critical role in tumor inhibition. However, the molecular mechanism of rottlerin-mediated anti-tumor activity is still ambiguous. It has been reported that EZH2 exhibits oncogenic functions in a variety of human cancers. Therefore, inhibition of EZH2 could be a promising strategy for the treatment of human cancers. In this study, we aim to explore whether rottlerin could inhibit tumorigenesis via suppression of EZH2 in prostate cancer cells. Multiple approaches such as FACS, Transwell invasion assay, RT-PCR, Western blotting, and transfection were performed to determine our aim. We found that rottlerin treatment led to inhibition of cell growth, migration and invasion, but induction of apoptosis in prostate cancer cells. Importantly, we defined that rottlerin decreased the expression of EZH2 and H3K27me3 in prostate cancer cells. Moreover, overexpression of EZH2 abrogated the rottlerin-induced inhibition of cell growth, migration, and invasion in prostate cancer cells. Consistently, down-regulation of EZH2 enhanced rottlerin-triggered anti-tumor function. Collectively, our work demonstrated that rottlerin exerted its tumor suppressive function via inhibition of EZH2 expression in prostate cancer cells. Our findings indicated that rottlerin might be a potential therapeutic compound for treating patients with prostate cancer.
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Affiliation(s)
- Nana Zheng
- a The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Soochow University , Suzhou , China
| | - Lixia Wang
- a The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Soochow University , Suzhou , China
| | - Yingying Hou
- a The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Soochow University , Suzhou , China
| | - Xiuxia Zhou
- a The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Soochow University , Suzhou , China
| | - Youhua He
- b Department of Urology , The Second Affiliated Hospital of Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - Zhiwei Wang
- a The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Soochow University , Suzhou , China.,b Department of Urology , The Second Affiliated Hospital of Wenzhou Medical University , Wenzhou, Zhejiang , China.,c Department of Biochemistry and Molecular Biology , School of Laboratory Medicine, Bengbu Medical College , Anhui , China
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Ma J, Hou Y, Xia J, Zhu X, Wang ZP. Tumor suppressive role of rottlerin in cancer therapy. Am J Transl Res 2018; 10:3345-3356. [PMID: 30662591 PMCID: PMC6291697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 10/10/2018] [Indexed: 06/09/2023]
Abstract
Cancer as a major public health problem is a big trouble to be cured at present in the world. Thus, it is essential to discover better anticancer drugs to treat cancer patients. It has been reported that rottlerin, a natural polyphenolic compound from the mature fruits of Mallotus philippinensis, possesses multiple anti-cancer biological activities. Rottlerin exhibited its antitumor property in a variety of human cancers, suggesting that rottlerin could be a potential agent for treating cancers. In this review we discuss the recent literature regarding the biological functions and tumor suppressive mechanisms of rottlerin in cancers. We hope rottlerin will be further exploited for potential treatment of human cancers.
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Affiliation(s)
- Jia Ma
- Department of Biochemistry and Molecular Biology, School of Laboratory Medicine, Bengbu Medical CollegeBengbu 233030, Anhui, China
| | - Yingying Hou
- Chinese Academy of Sciences Shanghai Institute of Materia MedicaShanghai 201203, China
| | - Jun Xia
- Department of Biochemistry and Molecular Biology, School of Laboratory Medicine, Bengbu Medical CollegeBengbu 233030, Anhui, China
| | - Xueqiong Zhu
- Departmant of Obstetrics and Gynecology, The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325027, Zhejiang, China
| | - Z Peter Wang
- Department of Biochemistry and Molecular Biology, School of Laboratory Medicine, Bengbu Medical CollegeBengbu 233030, Anhui, China
- Center of Scientific Research, The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325027, Zhejiang, China
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBoston, MA, USA
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Maurya AK, Vinayak M. Improved synergistic anticancer efficacy of quercetin in combination with PI-103, rottlerin, and G0 6983 against MCF-7 and RAW 264.7 cells. In Vitro Cell Dev Biol Anim 2019; 55:36-44. [PMID: 30413935 DOI: 10.1007/s11626-018-0309-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 11/01/2018] [Indexed: 01/21/2023]
Abstract
Flavonoids have been chronicles of the history of a long way journey in the cure of physiological or pathophysiological conditions in various diseases including cancer. Our previous findings suggest the extensive mechanism of quercetin (QUE) mediated regression of cell survival, cell proliferation, oxidative stress, inflammation, and angiogenesis via modulating PI3K and PKC signaling in lymphoma as well as hepatocellular carcinoma. PI3K-PKC pathway is a key monitor of mammalian cells regulated by its different isoenzymes, which may exert similar or opposite cellular effects by differential coupling of signaling pathways. Put forward the invention of selective inhibitors against various isoenzymes is beneficial to reduce the burden of inclusive deleterious effects of drug for normal physiological process. Therefore, we hypothesized the improved anticancer efficacy of QUE in combination with isoenzyme inhibitors-rottlerin (ROT-PKCδ inhibitor), G0 6983 (PKCα inhibitor), and PI-103 (p110α-class I PI3K inhibitor) in MCF-7 and RAW 264.7 cells. QUE significantly improves the cytotoxicity of ROT + G0 6983 ranged 30-55% and PI-103 ranged 24-63% after 24-48 h against MCF-7 cells. Additionally in the presence of QUE, the improved cytotoxicity of ROT + G0 6983 is observed to range 69-75% and PI-103 ranged 45-88% after 24-48 h in RAW 264.7 cells. This increment in cell deaths are positively correlated with enhanced morphological alteration observed in MCF-7 cells. Further, QUE significantly increases the attenuation of PKCα level approximately by 50% in combination with PI-103. Overall results of the current study suggested that QUE improves the synergistic anticancer efficacy in combination with PI-103, ROT, and G0 6983 in MCF-7 and RAW 264.7 cells.
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Abstract
PURPOSE Autophagy, as a highly conserved cellular degradation and recycling process, plays an important part in maintaining cellular homeostasis. PKC signaling is involved in multiple pathways including cell cycle progression, tumorigenesis, migration and autophagy. METHODS Literatures about PKC and autophagy from PubMed databases were reviewed in this study. RESULTS Studies regarding the association of PKC and autophagy remain debatable. Different duration of the stimulation of autophagy and distinct cell contexts result in different function of PKC in regulating autophagy. The subcellular localization of PKCs and their downstream regulators may influence the autophagy regulation as well. As important intracellular components, the mitochondria play an important role in regulating autophagy, by metabolic modulation and structural derangement. CONCLUSION Phase II studies regarding PKC-β inhibitor, enzastaurin, showed promising results in MCL, DLBCL and recurrent high-grade gliomas. However, the detailed mechanism is still in need. The mechanism of PKC-β in mediating autophagy in lymphoma and high-grade gliomas remains elusive as well. Moreover, several studies were in agreement that rottlerin enhanced autophagy in breast cancer cells, which warrants further clinical studies to verify PKC-δ as a therapeutic target. Thus, identifying the function of PKC in modulating autophagy and conducting related clinical studies help find novel target for chemotherapy.
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Affiliation(s)
- Tianyi Wang
- NHC Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, 1163 Xinmin Street, Changchun, 130021, People's Republic of China
| | - Conghe Liu
- NHC Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, 1163 Xinmin Street, Changchun, 130021, People's Republic of China
| | - Lili Jia
- NHC Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, 1163 Xinmin Street, Changchun, 130021, People's Republic of China.
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Tomkova S, Misuth M, Lenkavska L, Miskovsky P, Huntosova V. In vitro identification of mitochondrial oxidative stress production by time-resolved fluorescence imaging of glioma cells. Biochim Biophys Acta Mol Cell Res 2018; 1865:616-628. [PMID: 29410069 DOI: 10.1016/j.bbamcr.2018.01.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 01/29/2018] [Accepted: 01/30/2018] [Indexed: 02/07/2023]
Abstract
Oxidative phosphorylation and glycolysis are important features, by which cells could bypass oxidative stress. The level of oxidative stress, and the ability of cells to promote oxidative phosphorylation or glycolysis, significantly determined proliferation or cell demise. In the present work, we have employed selective mitochondrial probe MitoTracker™ Orange CMTM/Ros (MTO) to estimate the level of oxidative stress in cancer cells at different stressed conditions. MTO is partially sensitive to decrease of mitochondrial membrane potential and to reactive oxygen species (ROS) generated in mitochondria. We have demonstrated, that fluorescence lifetime of MTO is much more sensitive to oxidative stress than intensity-based approaches. This method was validated in different cancer cell lines. Our approach revealed, at relatively low ROS levels, that Gö 6976, a protein kinase C (PKC) α inhibitor, and rottlerin, an indirect PKCδ inhibitor, increased mitochondrial ROS level in glioma cell. Their involvement in oxidative phosphorylation and apoptosis was investigated with oxygen consumption rate estimation, western blot and flow-cytometric analysis. Our study brings new insight to identify feeble differences in ROS production in living cells.
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Affiliation(s)
- Silvia Tomkova
- Department of Biophysics, Faculty of Science, P. J. Safarik University in Kosice, Jesenna 5, 041 54, Kosice, Slovakia
| | - Matus Misuth
- Department of Biophysics, Faculty of Science, P. J. Safarik University in Kosice, Jesenna 5, 041 54, Kosice, Slovakia
| | - Lenka Lenkavska
- Department of Biophysics, Faculty of Science, P. J. Safarik University in Kosice, Jesenna 5, 041 54, Kosice, Slovakia
| | - Pavol Miskovsky
- Center for Interdisciplinary Biosciences, Technology and innovation park, P.J. Safarik University in Kosice, Jesenna 5, 041 54, Kosice, Slovakia; SAFTRA photonics Ltd., Jesenna 5, 041 54, Kosice, Slovakia
| | - Veronika Huntosova
- Center for Interdisciplinary Biosciences, Technology and innovation park, P.J. Safarik University in Kosice, Jesenna 5, 041 54, Kosice, Slovakia.
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Hemachandran H, Jain F, Mohan S, Kumar D T, Priya Doss C G, Ramamoorthy S. Glandular hair constituents of Mallotus philippinensis Muell. fruit act as tyrosinase inhibitors: Insights from enzyme kinetics and simulation study. Int J Biol Macromol 2017; 107:1675-1682. [PMID: 29054523 DOI: 10.1016/j.ijbiomac.2017.10.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 10/04/2017] [Accepted: 10/06/2017] [Indexed: 12/23/2022]
Abstract
The glandular hair extracts from the fruit rind of Mallotus philippinensis Muell. is employed to treat various skin infections, however the anti-tyrosinase activity remains unknown. Hence the present study inspected on the anti-melanogenic activity of M. philippinensis constituents. Lineweaver Burk plot revealed mixed inhibition for Rottlerin; non-competitive type of inhibition for mallotophilippen A and B respectively. Thermodynamic studies resulted in static quenching forming ground state complex with higher binding constant temperature dependently. Fluorescence and circular dichroism study implicated conformational change in secondary and tertiary structure of tyrosinase. Molecular docking suggests rottlerin has high binding affinity to the active site pocket of tyrosinase. Simulation study further proved that the compactness of inhibitor with tyrosinase by hydrogen bonding influenced the stability of the enzyme. Depigmentation efficacy is further proved in Aspergillus niger spores. Thus our findings delineate that rottlerin could be utilized as a depigmentation agent in food pharmaceutical and agricultural industries.
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Affiliation(s)
- Hridya Hemachandran
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India
| | - Fagun Jain
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India
| | - Sankari Mohan
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India
| | - Thirumal Kumar D
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India
| | - George Priya Doss C
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India
| | - Siva Ramamoorthy
- School of Bio Sciences and Technology, VIT University, Vellore - 632014, Tamil Nadu, India.
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Abdelnabi R, Amrun SN, Ng LFP, Leyssen P, Neyts J, Delang L. Protein kinases C as potential host targets for the inhibition of chikungunya virus replication. Antiviral Res 2016; 139:79-87. [PMID: 28039020 DOI: 10.1016/j.antiviral.2016.12.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/10/2016] [Accepted: 12/26/2016] [Indexed: 02/07/2023]
Abstract
We have shown previously that prostratin, a non-tumor promoting phorbol ester, inhibits chikungunya virus (CHIKV)-induced cytopathic effects in vitro. Prostratin is a potent activator of protein kinases C (PKC), a family of related serine/threonine kinases that regulate many cellular processes such as proliferation and apoptosis. The objective of this study was to explore the mechanism of the anti-CHIKV activity of prostratin. Prostratin reduced the production of infectious virus particles and viral protein accumulation in a dose-dependent manner at a post-entry step during virus replication. The antiviral effect of the compound was cell-dependent, with potent antiviral activity observed in human skin fibroblasts cells, the primary target cells of CHIKV infection. The antiviral activity of prostratin was markedly reduced in the presence of PKC inhibitors, therefore confirming that the antiviral effect results from an activation of PKCs. Together these results showed that PKCs are potential host targets for the inhibition of CHIKV replication.
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Affiliation(s)
- Rana Abdelnabi
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Siti Naqiah Amrun
- Laboratory of Microbial Immunity, Singapore Immunology Network, Agency for Science, Technology, and Research, Singapore
| | - Lisa F P Ng
- Laboratory of Microbial Immunity, Singapore Immunology Network, Agency for Science, Technology, and Research, Singapore
| | - Pieter Leyssen
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Johan Neyts
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium.
| | - Leen Delang
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
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Su J, Wang L, Yin X, Zhao Z, Hou Y, Ye X, Zhou X, Wang Z. Rottlerin exhibits anti-cancer effect through inactivation of S phase kinase-associated protein 2 in pancreatic cancer cells. Am J Cancer Res 2016; 6:2178-2191. [PMID: 27822410 PMCID: PMC5088284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023] Open
Abstract
Rottlerin, a natural product isolated from Mallotus philippinensis, has been characterized as an effective chemoprevention agent in inhibiting tumor cell growth. Although multiple studies have revealed the role of rottlerin in tumorigenesis, the molecular mechanism of rottlerin-mediated anti-tumor activity has not been fully elucidated. It has been reported that Skp2 (S-phase kinase associated protein 2) plays an oncogenic role in human malignancies, indicating that inactivation of Skp2 could be a promising approach for the treatment of cancers. Therefore, in this study, we aim to investigate whether rottlerin exhibits its anti-tumor activities via targeting Skp2 pathway in pancreatic cancer. We found that rottlerin inhibited cell growth, induced apoptosis, arrested cell cycle, and retarded cell invasion and migration. Notably, we observed that the expression of Skp2 was significantly decreased in rottlerin-treated pancreatic cancer cells. Importantly, overexpression of Skp2 abrogated the anti-tumor function induced by rottlerin in pancreatic cancer cells. Consistently, depletion of Skp2 promoted rottlerin-mediated inhibition of cell growth and invasion. Collectively, our study demonstrated that rottlerin could suppress Skp2 expression and subsequently exert its tumor suppressive function in pancreatic cancer cells, suggesting that rottlerin might be a potential therapeutic compound for treating pancreatic cancer.
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Affiliation(s)
- Jingna Su
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Lixia Wang
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Xuyuan Yin
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Zhe Zhao
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Yingying Hou
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Xiantao Ye
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Xiuxia Zhou
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
| | - Zhiwei Wang
- The Cyrus Tang Hematology Center and Collaborative Innovation Center of Hematology, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow UniversitySuzhou 215123, China
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical SchoolMA 02215, USA
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Chhiber N, Kaur T, Singla S. Rottlerin, a polyphenolic compound from the fruits of Mallotus phillipensis (Lam.) Müll.Arg., impedes oxalate/calcium oxalate induced pathways of oxidative stress in male wistar rats. Phytomedicine 2016; 23:989-97. [PMID: 27444343 DOI: 10.1016/j.phymed.2016.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 06/02/2016] [Accepted: 06/08/2016] [Indexed: 05/20/2023]
Abstract
BACKGROUND Oxalate and/or calcium oxalate, is known to induce free radical production, subsequently leading to renal epithelial injury. Oxidative stress and mitochondrial dysfunction have emerged as new targets for managing oxalate induced renal injury. HYPOTHESIS Plant products and antioxidants have gained tremendous attention in the prevention of lithiatic disease. Rottlerin, a polyphenolic compound from the fruits of Mallotus phillipensis (Lam.) Müll.Arg., has shown free radical scavenging, antioxidant activity and has been reported to interfere in signaling pathways leading to inflammation and apoptosis. In this study, the potential role of rottlerin, in rats exposed to hyperoxaluric environment was explored. METHODS Hyperoxaluria was induced by administering 0.4% ethylene glycol and 1% ammonium chloride in drinking water to male wistar rats for 9 days. Rottlerin was administered intraperitoneally at 1mg/kg/day along with the hyperoxaluric agent. Prophylactic efficacy of rottlerin to diminish hyperoxaluria induced renal dysfunctionality and crystal load was examined along with its effect on free radicals generating pathways in hyperoxaluric rats. RESULTS 0.4% ethylene glycol and 1% ammonium chloride led to induction of hyperoxaluria, oxiadtive stress and mitochondrial damage in rats. Rottlerin treatment reduced NADPH oxidase activity, prevented mitochondrial dysfunction and maintained antioxidant environment. It also refurbished renal functioning, tissue integrity and diminished urinary crystal load in hyperoxaluric rats treated with rottlerin. CONCLUSIONS Thus, the present investigation suggests that rottlerin evidently reduced hyperoxaluric consequences and the probable mechanism of action of this drug could be attributed to its ability to quench free radicals by itself and interrupting signaling pathways involved in pathogenesis of stone formation.
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Affiliation(s)
- Nirlep Chhiber
- Department of Biochemistry, Panjab University, Chandigarh-160015, India
| | - Tanzeer Kaur
- Department of Biophysics, Panjab University, Chandigarh-160015, India
| | - Surinder Singla
- Department of Biochemistry, Panjab University, Chandigarh-160015, India.
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Daveri E, Maellaro E, Valacchi G, Ietta F, Muscettola M, Maioli E. Inhibitions of mTORC1 and 4EBP-1 are key events orchestrated by Rottlerin in SK-Mel-28 cell killing. Cancer Lett 2016; 380:106-13. [PMID: 27343979 DOI: 10.1016/j.canlet.2016.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/16/2016] [Accepted: 06/18/2016] [Indexed: 02/04/2023]
Abstract
Earlier studies demonstrated that Rottlerin exerts a time- and dose-dependent antiproliferative effect on SK-Mel-28 melanoma cells during 24 h of treatment, but cytotoxicity due to cell death began only after a 48 h exposure. In the current study, in order to identify the type of cell death in this cell line, which is notoriously refractory to most anticancer therapies, and to clarify the underlying mechanisms of this delayed outcome, we searched for apoptotic, necrotic/necroptotic and autophagic traits in Rottlerin-exposed cells. Although SK-Mel-28 cells are both apoptosis and autophagy competent, Western blotting analysis, caspase activity assay, nuclear imaging and the effects of autophagy, apoptosis and necroptosis inhibitors, indicated that Rottlerin cytotoxicity was due to none of the aforementioned death mechanisms. Nevertheless, in growth arrested cells, the death did occur after a prolonged treatment and most likely ensued from the observed blockage of protein synthesis that reached levels expected to be incompatible with cell survival. From a mechanistic point of view, we ascribed this effect to the documented inhibition of mTORC1 activity; mTORC1 inhibition on the one hand led to a not deadly, rather protective autophagic response but, on the other hand caused a near complete arrest of protein synthesis. Interestingly, no cytotoxicity was found towards normal skin fibroblasts, which only resulted mildly growth arrested by the drug.
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Affiliation(s)
- E Daveri
- Department of Life Sciences, University of Siena, via Aldo Moro 7, 53100 Siena, Italy
| | - E Maellaro
- Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro 7, 53100 Siena, Italy
| | - G Valacchi
- Department of Biology and Evolution, University of Ferrara, Via Luigi Borsari 46, 44100 Ferrara, Italy
| | - F Ietta
- Department of Life Sciences, University of Siena, via Aldo Moro 7, 53100 Siena, Italy
| | - M Muscettola
- Department of Medicine, Surgery and Neuroscience, University of Siena, Strada delle Scotte 4, 53100 Siena, Italy
| | - E Maioli
- Department of Life Sciences, University of Siena, via Aldo Moro 7, 53100 Siena, Italy.
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Liao TY, Tzeng WY, Wu HH, Cherng CG, Wang CY, Hu SSJ, Yu L. Rottlerin impairs the formation and maintenance of psychostimulant-supported memory. Psychopharmacology (Berl) 2016; 233:1455-65. [PMID: 26960698 DOI: 10.1007/s00213-016-4251-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 02/07/2016] [Indexed: 02/07/2023]
Abstract
RATIONALE AND OBJECTIVE Since brain proteins such as protein kinase C (PKC), brain-derived neurotrophic factor (BDNF), and mammalian target of rapamycin (mTOR) are involved in the establishment and maintenance of psychostimulant memory, we sought to determine if systemic treatment with rottlerin, a natural compound affecting all these proteins, may modulate stimulant-supported memory. MATERIALS AND METHODS Stimulant-induced conditioned place preference (CPP) was used in modeling stimulant-supported memory. RESULTS Three cocaine (10 mg/kg; COC) or three methamphetamine (1 mg/kg; MA) conditioning trials reliably established the drug-induced CPP in male C57BL/6 mice. An intra-peritoneal rottlerin injection (5 mg/kg) at least 24 h prior to the first COC or first MA conditioning trial prevented the establishment of CPP. Following the establishment of the COC- or MA-induced CPP, saline conditioning trial was used to extinguish the CPP. Rottlerin (5 mg/kg, intra-peritoneal (i.p.)) administered 20 h prior to the first saline conditioning trial diminished subsequent drug- and stressor-primed reinstatement of the extinguished CPP. Rottlerin (5 mg/kg, i.p.) produced a fast-onset and long-lasting increase in hippocampal BDNF levels. However, treatment with a BDNF tropomyosin receptor kinase B (TrkB) receptor antagonist, K252a (5 μg/kg), did not affect rottlerin's suppressing effect on COC-induced CPP and treatment with 7,8-dihydroxyflavone (10 mg/kg x 6, 7,8-DHF), a selective TrkB agonist, prior to each conditioning trial did not affect COC-induced CPP. CONCLUSION These results suggest that systemic rottlerin treatment may impair the formation of COC- and MA-supported memory. Importantly, such a treatment may advance our understanding of the underlying mechanism through which extinction training resulted in the "forgetting" of the COC- and MA-supported memory.
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Affiliation(s)
- Tien You Liao
- Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, 1 University Rd., Tainan, 70101, Taiwan, ROC
| | - Wen-Yu Tzeng
- Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, 1 University Rd., Tainan, 70101, Taiwan, ROC
| | - Hsin-Hua Wu
- Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, 1 University Rd., Tainan, 70101, Taiwan, ROC
| | - Chianfang G Cherng
- Department of Health Psychology, Chang Jung Christian University, Tainan, 71101, Taiwan, ROC
| | - Ching-Yi Wang
- Institute of Basic Medical Sciences, National Cheng Kung University College of Medicine, Tainan, 70101, Taiwan, ROC
| | - Sherry S-J Hu
- Department of Psychology, National Cheng Kung University, Tainan, 70101, Taiwan, ROC
| | - Lung Yu
- Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, 1 University Rd., Tainan, 70101, Taiwan, ROC. .,Institute of Basic Medical Sciences, National Cheng Kung University College of Medicine, Tainan, 70101, Taiwan, ROC.
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25
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Huang SP, Chien JY, Tsai RK. Ethambutol induces impaired autophagic flux and apoptosis in the rat retina. Dis Model Mech 2015; 8:977-87. [PMID: 26092127 PMCID: PMC4527287 DOI: 10.1242/dmm.019737] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 06/07/2015] [Indexed: 12/11/2022] Open
Abstract
Ethambutol (EMB), an effective first-line antituberculosis agent, can cause serious visual impairment or irreversible vision loss in a significant number of patients. However, the mechanism underlying this ocular cytotoxicity remains to be elucidated. In this study, we found that there were statistically significant dose- and time-dependent increases in the number of cytoplasmic vacuoles and the level of cell death in EMB-treated RGC-5 cells (retinal ganglion cells). The protein kinase C (PKC)δ inhibitor rottlerin markedly reduced the EMB-induced activation of caspase-3 and the subsequent apoptosis of RGC-5 cells. Western blot analysis revealed that the expression levels of class III PI3K, Beclin-1, p62 and LC3-II were upregulated, and LC3 immunostaining results showed activation of the early phase and inhibition of the late stage of autophagy in retinas of the EMB-intraperitoneal (IP)-injected rat model. We further demonstrated that exposure to EMB induces autophagosome accumulation, which results from the impaired autophagic flux that is mediated by a PKCδ-dependent pathway, inhibits the PI3K/Akt/mTOR signaling pathway and leads to apoptotic death in retina neuronal cells. These results indicate that autophagy dysregulation in retinal neuronal cells might play a substantial role in EMB-induced optic neuroretinopathy. Summary: This study provides the first evidence that EMB induces autophagosome accumulation, which results from the impaired autophagic flux that is mediated by a PKCδ-dependent pathway, and leads to apoptotic death in retina neuronal cells.
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Affiliation(s)
- Shun-Ping Huang
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien 97002, Taiwan
| | - Jia-Ying Chien
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien 97002, Taiwan
| | - Rong-Kung Tsai
- Institute of Eye Research, Buddhist Tzu Chi General Hospital, Hualien 97002, Taiwan Institute of Medical Sciences, Tzu Chi University, Hualien 97002, Taiwan
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26
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Torricelli C, Daveri E, Salvadori S, Valacchi G, Ietta F, Muscettola M, Carlucci F, Maioli E. Phosphorylation-independent mTORC1 inhibition by the autophagy inducer Rottlerin. Cancer Lett 2015; 360:17-27. [PMID: 25661734 DOI: 10.1016/j.canlet.2015.01.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 01/26/2015] [Accepted: 01/27/2015] [Indexed: 02/07/2023]
Abstract
We recently found that Rottlerin not only inhibits proliferation but also causes Bcl-2- and Beclin 1-independent autophagic death in apoptosis-resistant breast adenocarcinoma MCF-7 cells. Having excluded a role for canonical signaling pathways, the current study was aimed to investigate the contribution of the AMPK/mTOR axis in autophagy induction and to search for the upstream signaling molecules potentially targeted by Rottlerin. Using several enzyme inhibitors, Western blotting analysis, mTOR siRNA and pull down assay, we demonstrate that the Rottlerin-triggered autophagy is mediated by inhibition of mTORC1 activity through a novel AMPK and mTORC1 phosphorylation-independent mechanism, likely mediated by the direct interaction between Rottlerin and mTOR.
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Affiliation(s)
- C Torricelli
- Department of Life Sciences, University of Siena, via Aldo Moro, Siena 7-53100, Italy
| | - E Daveri
- Department of Life Sciences, University of Siena, via Aldo Moro, Siena 7-53100, Italy
| | - S Salvadori
- Department of Life Sciences, University of Siena, via Aldo Moro, Siena 7-53100, Italy
| | - G Valacchi
- Department of Biology and Evolution, University of Ferrara, Via Luigi Borsari 46, Ferrara 44100, Italy; Department of Food and Nutrition, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - F Ietta
- Department of Life Sciences, University of Siena, via Aldo Moro, Siena 7-53100, Italy
| | - M Muscettola
- Department of Medicine, surgery and neuroscience, University of Siena, Strada delle Scotte, Siena 4-53100, Italy
| | - F Carlucci
- Department of Medical biotechnologies, University of Siena, Strada delle Scotte, Siena 4-53100, Italy
| | - E Maioli
- Department of Life Sciences, University of Siena, via Aldo Moro, Siena 7-53100, Italy.
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27
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Huang M, Tang SN, Upadhyay G, Marsh JL, Jackman CP, Srivastava RK, Shankar S. Rottlerin suppresses growth of human pancreatic tumors in nude mice, and pancreatic cancer cells isolated from Kras(G12D) mice. Cancer Lett 2014; 353:32-40. [PMID: 25050737 DOI: 10.1016/j.canlet.2014.06.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/12/2014] [Accepted: 06/09/2014] [Indexed: 01/29/2023]
Abstract
The purpose of the study was to examine the molecular mechanisms by which rottlerin inhibited growth of human pancreatic tumors in Balb C nude mice, and pancreatic cancer cells isolated from Kras(G12D) mice. AsPC-1 cells were injected subcutaneously into Balb c nude mice, and tumor-bearing mice were treated with rottlerin. Cell proliferation and apoptosis were measured by Ki67 and TUNEL staining, respectively. The expression of components of Akt, Notch, and Sonic Hedgehog (Shh) pathways were measured by the immunohistochemistry, Western blot analysis, and/or q-RT-PCR. The effects of rottlerin on pancreatic cancer cells isolated from Kras(G12D) mice were also examined. Rottlerin-treated mice showed a significant inhibition in tumor growth which was associated with suppression of cell proliferation, activation of capase-3 and cleavage of PARP. Rottlerin inhibited the expression of Bcl-2, cyclin D1, CDK2 and CDK6, and induced the expression of Bax in tumor tissues compared to untreated control. Rottlerin inhibited the markers of angiogenesis (Cox-2, VEGF, VEGFR, and IL-8), and metastasis (MMP-2 and MMP-9), thus blocking production of tumorigenic mediators in tumor microenvironment. Rottlerin also inhibited epithelial-mesenchymal transition by up-regulating E-cadherin and inhibiting the expression of Slug and Snail. Furthermore, rottlerin treatment of xenografted tumors or pancreatic cancer cells isolated from Kras(G12D) mice showed a significant inhibition in Akt, Shh and Notch pathways compared to control groups. These data suggest that rottlerin can inhibit pancreatic cancer growth by suppressing multiple signaling pathways which are constitutively active in pancreatic cancer. Taken together, our data show that the rottlerin induces apoptosis and inhibits pancreatic cancer growth by targeting Akt, Notch and Shh signaling pathways, and provide a new therapeutic approach with translational potential for humans.
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Affiliation(s)
- Minzhao Huang
- Department of Pharmacology, Toxicology and Therapeutics, and Medicine, The University of Kansas Cancer Center, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
| | - Su-Ni Tang
- Department of Pharmacology, Toxicology and Therapeutics, and Medicine, The University of Kansas Cancer Center, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
| | - Ghanshyam Upadhyay
- Department of Pharmacology, Toxicology and Therapeutics, and Medicine, The University of Kansas Cancer Center, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
| | - Justin L Marsh
- Department of Biochemistry, University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
| | - Christopher P Jackman
- Department of Biochemistry, University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
| | - Rakesh K Srivastava
- Department of Pharmacology, Toxicology and Therapeutics, and Medicine, The University of Kansas Cancer Center, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA.
| | - Sharmila Shankar
- Kansas City VA Medical Center, 4801 Linwood Boulevard, Kansas City, MO 64128, USA.
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28
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Lu W, Lin C, Li Y. Rottlerin induces Wnt co-receptor LRP6 degradation and suppresses both Wnt/β-catenin and mTORC1 signaling in prostate and breast cancer cells. Cell Signal 2014; 26:1303-9. [PMID: 24607787 DOI: 10.1016/j.cellsig.2014.02.018] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 02/10/2014] [Accepted: 02/22/2014] [Indexed: 02/06/2023]
Abstract
Activation of Wnt/β-catenin signaling can result in up-regulation of mTORC1 signaling in cancer cells. The low density lipoprotein receptor-related protein-6 (LRP6) is an essential Wnt co-receptor for Wnt/β-catenin signaling. We found that rottlerin, a natural plant polyphenol, suppressed LRP6 expression and phosphorylation, and inhibited Wnt/β-catenin signaling in HEK293 cells. Furthermore, the inhibitory effects of rottlerin on LRP6 expression/phosphorylation and Wnt/β-catenin signaling were confirmed in human prostate cancer PC-3 and DU145 cells and breast cancer MDA-MB-231 and T-47D cells. Mechanistically, rottlerin promoted LRP6 degradation, but had no effects on LRP6 transcriptional activity. In addition, rottlerin-mediated LRP6 down-regulation was unrelated to activation of 5'-AMP-activated protein kinase (AMPK). Importantly, we also found that rottlerin inhibited mTORC1 signaling in prostate and breast cancer cells. Finally, we demonstrated that rottlerin was able to suppress the expression of cyclin D1 and survivin, two targets of both Wnt/β-catenin and mTORC1 signaling, in prostate and breast cancer cells, and displayed remarkable anticancer activity with IC(50) values between 0.7 and 1.7 μM for prostate cancer PC-3 and DU145 cells and breast cancer MDA-MB-231 and T-47D cells. The IC(50) values are comparable to those shown to suppress the activities of Wnt/β-catenin and mTORC1 signaling in prostate and breast cancer cells. Our data indicate that rottlerin is a novel LRP6 inhibitor and suppresses both Wnt/β-catenin and mTORC1 signaling in prostate and breast cancer cells, and that LRP6 represents a potential therapeutic target for cancers.
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Affiliation(s)
- Wenyan Lu
- Department of Biochemistry and Molecular Biology, Drug Discovery Division, Southern Research Institute, 2000 Ninth Avenue South, Birmingham, AL 35255, USA
| | - Cuihong Lin
- Department of Biochemistry and Molecular Biology, Drug Discovery Division, Southern Research Institute, 2000 Ninth Avenue South, Birmingham, AL 35255, USA; Department of Pharmacy, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Yonghe Li
- Department of Biochemistry and Molecular Biology, Drug Discovery Division, Southern Research Institute, 2000 Ninth Avenue South, Birmingham, AL 35255, USA.
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Fan Y, Li J, Zhang YQ, Jiang LH, Zhang YN, Yan CQ. Protein kinase C delta mediated cytotoxicity of 6-Hydroxydopamine via sustained extracellular signal-regulated kinase 1/2 activation in PC12 cells. Neurol Res 2013; 36:53-64. [PMID: 24107416 DOI: 10.1179/1743132813y.0000000267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVES The incidence of Parkinson's disease (PD) is increasing as the global population ages. 6-hydroxydopamine (6-OHDA) can induce PD-like neuropathology and biochemical changes in both in vitro and in vivo models. Therefore, clarification of the molecular mechanism of 6-OHDA-induced cell death might contribute to the understanding of the pathogenesis of PD. METHODS With this goal in mind, we investigated the role of protein kinase C delta (PKC delta) in 6-OHDA-dependent death using the pheochromocytoma cell line, PC12. Cells were treated with 6-OHDA to induce toxicity with or without pretreatment using rottlerin (a PKC delta inhibitor), bisindolylmaleimide I (a general PKC inhibitor), Gö6976 (a PKC inhibitor selective for calcium-dependent PKC isoforms), or phorbol-12-myristate-13-acetate (PMA, a PKC activator). RESULTS Phorbol-12-myristate-13-acetate decreased cell survival and increased the rate of apoptosis while rottlerin increased cell survival and decreased the rate of apoptosis. In contrast, neither bisindolylmaleimide I nor Gö6976 affected 6-OHDA-induced cell death. Western analysis demonstrated that phosphorylation of PKC delta on Thr 505 as well as extracellular signal-regulated kinase (ERK) phosphorylation increased after exposure to 6-OHDA. This increase in PKC delta phosphorylation was potentiated by PMA. However, rottlerin attenuated the 6-OHDA-stimulated increase in PKC delta and ERK phosphorylation. CONCLUSION These data suggest that PKC delta, rather than classic-type PKC (alpha, beta1, beta2, gamma), participates in 6-OHDA-induced neurotoxicity in PC12 cells, and PKC delta activity is required for subsequent ERK activation during cell death.
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30
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Chan TK, Ng DSW, Cheng C, Guan SP, Koh HM, Wong WSF. Anti-allergic actions of rottlerin from Mallotus philippinensis in experimental mast cell-mediated anaphylactic models. Phytomedicine 2013; 20:853-860. [PMID: 23632085 DOI: 10.1016/j.phymed.2013.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/04/2013] [Accepted: 03/09/2013] [Indexed: 05/28/2023]
Abstract
Allergy is an acquired hypersensitivity reaction of the immune system mediated by cross-linking of the allergen-specific IgE-bound high-affinity IgE receptors, leading to immediate mast cell degranulation. Rottlerin is an active molecule isolated from Mallotus philippinensis, a medicinal plant used in Ayurvedic Medicine System for anti-allergic and anti-helminthic treatments. The present study investigated potential anti-allergic effects of rottlerin in animal models of IgE-dependent anaphylaxis and the anti-allergic mechanisms of action of rottlerin in mast cells. Anti-allergic actions of rottlerin were evaluated in passive cutaneous anaphylaxis and passive systemic anaphylaxis mouse models, and in anaphylactic contraction of bronchial rings isolated from sensitized guinea pigs. Direct mast cell-stabilizing effect of rottlerin was examined in RBL-2H3 mast cell line. Anti-allergic signaling mechanisms of action of rottlerin in mast cells were also examined. Rottlerin prevented IgE-mediated cutaneous vascular extravasation, hypothermia, elevation in plasma histamine level and tracheal tissue mast cell degranulation in mice in a dose-dependent manner. In addition, rottlerin suppressed ovalbumin-induced guinea pig bronchial smooth muscle contraction. Furthermore, rottlerin concentration-dependently blocked IgE-mediated immediate release of β-hexosaminidase from RBL-2H3 mast cells. Rottlerin was found to inhibit IgE-induced PLCγ1 and Akt phosphorylation, production of IP3 and rise in cytosolic Ca²⁺ level in mast cells. We report here for the first time that rottlerin possesses anti-allergic activity by blocking IgE-induced mast cell degranulation, providing a foundation for developing rottlerin for the treatment of allergic asthma and other mast cell-mediated allergic disorders.
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Affiliation(s)
- Tze Khee Chan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, Singapore
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31
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Lu QY, Zhang L, Lugea A, Moro A, Edderkaoui M, Eibl G, Pandol SJ, Go VLW. Determination of Rottlerin, a Natural Protein Kinases C Inhibitor, in Pancreatic Cancer Cells and Mouse Xenografts by RP-HPLC Method. J Chromatogr Sep Tech 2013; 4:100062. [PMID: 24482742 DOI: 10.4172/2157-7064.1000162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Rottlerin is a natural polyphenolic ketone isolated from the pericarps of Mallotus phillippinensis. In previous studies we showed that parenteral administration of rottlerin reduced tumor growth in murine xenograft models of pancreatic cancer. The aim of this study was to develop a simple and validated method for the quantitative determination of rottlerin in plasma and tumor tissues of mice fed a rottlerin diet. A xenograft model of pancreatic cancer was prepared by injection of 2×106 HPAF-II cells subcutaneously into nude mice. One week before tumor implantation, mice were randomly allocated to standard diet (AIN76A) and standard diet supplement with 0.012% rottlerin (n=6 per group). Mice were sacrificed after 6 weeks on diets. Rottlerin was extracted from the plasma and tissues using protein precipitation-extraction and analyzed by reverse-phase HPLC-DAD method. The same HPLC method was also applied to determine rottlerin levels in conditioned culture media and in cell lysates from HPAF-II cells exposed to 25 µM concentration of rottlerin. A substantial amount of rottlerin was detected in tumor (2.11 ± 0.25 nmol/g tissue) and plasma (2.88 ± 0.41 µM) in mice fed rottlerin diet. In addition, significant levels of rottlerin (57.4 ± 5.4 nmol/mg protein) were detected in cell lysates from rottlerin-treated HPAF-II cells. These data indicate that rottlerin is efficiently absorbed in cells and tissues both in vivo and in vitro and suggest a strong potential for rottlerin as a preventive or adjuvant supplement for pancreatic cancer.
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Affiliation(s)
- Qing-Yi Lu
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Lifeng Zhang
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Aurelia Lugea
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA ; Veterans Affairs Greater Los Angeles Healthcare System, University of California, Los Angeles, CA, USA
| | - Aune Moro
- Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Mouad Edderkaoui
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA ; Veterans Affairs Greater Los Angeles Healthcare System, University of California, Los Angeles, CA, USA
| | - Guido Eibl
- Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Stephen J Pandol
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA ; Veterans Affairs Greater Los Angeles Healthcare System, University of California, Los Angeles, CA, USA
| | - Vay-Liang W Go
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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Patel RK, Patel VR, Patel MG. Development and validation of a RP-HPLC method for the simultaneous determination of Embelin, Rottlerin and Ellagic acid in Vidangadi churna. J Pharm Anal 2012; 2:366-371. [PMID: 29403768 PMCID: PMC5760769 DOI: 10.1016/j.jpha.2012.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 03/06/2012] [Indexed: 11/28/2022] Open
Abstract
Vidangadi churna is a popular Ayurvedic formulation described in the chapter Krimicikitsa of the Ayurvedic literature Cakradatta for the treatment of Krimiroga. The preparation is a composite mixture of the fine powder of fruits of Vidang (Embelia ribs), glandular trichomes of the fruits of Kamala (Mallotus philippensis), mature fruits of Harde (Terminalia chebula), Saindhava and Yavakshara. The use of reversed phase C18 column eluted with gradient mobile phase of acetonitrile and water enabled the efficient separation of the chemical markers in 22 min. Validation of the method was performed in order to demonstrate its selectivity, accuracy, precision, repeatability and recovery. All calibration curves showed good linear correlation coefficients (r2>0.995) within the tested ranges. Three markers in Vidangadi churna were quantified with respect to Embelin (0.647%, w/w), Rottlerin (4.419%, w/w), and Ellagic acid (0.459%, w/w). Intra-and inter-day RSDs of retention times and peak areas were less than 3.12%. The recoveries were between 99.66% and 102.33%. In conclusion, a method has been developed for the simultaneous quantification of three markers in Vidangadi churna. The RP-HPLC method was simple, precise and accurate and can be used for the quality control of the raw materials as well as formulations.
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Affiliation(s)
- Rakesh K Patel
- S.K. Patel College of Pharmaceutical Education and Research, Kherva, Mehsana, India
| | - Vishal R Patel
- Department of Pharmacognosy, Baroda College of Pharmacy, Parul Group of Institutes, Limda, Vadodara, Gujarat 391760, India
| | - Madhavi G Patel
- Parul Institute of Pharmacy, Parul Group of Institutes, Limda, Vadodara, India
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