1
|
Liu Z, Li Q, Wang X, Wu Y, Zhang Z, Mao J, Gong S. Proanthocyanidin enhances the endogenous regeneration of alveolar bone by elevating the autophagy of PDLSCs. J Periodontal Res 2023; 58:1300-1314. [PMID: 37715945 DOI: 10.1111/jre.13186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 07/31/2023] [Accepted: 09/01/2023] [Indexed: 09/18/2023]
Abstract
OBJECTIVE This study aimed to investigate the effect of proanthocyanidin (PA) on osteogenesis mediated by periodontal ligament stem cells (PDLSCs) and endogenous alveolar bone regeneration. BACKGROUND Leveraging the osteogenic potential of resident stem cells is a promising strategy for alveolar bone regeneration. PA has been reported to be effective in osteogenesis. However, the effect and mechanism of PA on the osteogenic differentiation of PDLSCs remain elusive. METHODS Human PDLSCs were treated with various doses of PA to assess the cell proliferation using Cell Counting Kit-8. The osteogenic differentiation ability was detected by qRT-PCR analysis, western blot analysis, Alizarin red S staining, and Alkaline Phosphatase staining. The level of autophagy was evaluated by confocal laser scanning microscopy, transmission electron microscopy, and western blot analysis. RNA sequencing was utilized to screen the potential signaling pathway. The alveolar bone defect model of rats was created to observe endogenous bone regeneration. RESULTS PA activated intracellular autophagy in PDLSCs, resulting in enhanced osteogenic differentiation. Moreover, this effect could be abolished by the autophagy inhibitor 3-Methyladenine. Mechanistically, the PI3K/Akt/mTOR pathway was negatively correlated with PA-mediated autophagy activation. Lastly, PA promoted the alveolar bone regeneration in vivo, and this effect was reversed when the autophagy process was blocked. CONCLUSION PA may activate autophagy by inhibiting PI3K/Akt/mTOR signaling pathway to promote the osteogenesis of PDLSCs and enhance endogenous alveolar bone regeneration.
Collapse
Affiliation(s)
- Zhuo Liu
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Qilin Li
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Xiangyao Wang
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Yaxin Wu
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Zhixing Zhang
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Jing Mao
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| | - Shiqiang Gong
- Center of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan, China
| |
Collapse
|
2
|
Laha D, Sarkar J, Maity J, Pramanik A, Howlader MSI, Barthels D, Das H. Polyphenolic Compounds Inhibit Osteoclast Differentiation While Reducing Autophagy through Limiting ROS and the Mitochondrial Membrane Potential. Biomolecules 2022; 12:biom12091220. [PMID: 36139058 PMCID: PMC9496366 DOI: 10.3390/biom12091220] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 08/22/2022] [Accepted: 08/28/2022] [Indexed: 11/16/2022] Open
Abstract
Polyphenolic compounds are a diverse group of natural compounds that interact with various cellular proteins responsible for cell survival, differentiation, and apoptosis. However, it is yet to be established how these compounds interact in myeloid cells during their differentiation and the molecular and intracellular mechanisms involved. Osteoclasts are multinucleated cells that originate from myeloid cells. They resorb cartilage and bone, maintain bone homeostasis, and can cause pathogenesis. Autophagy is a cellular mechanism that is responsible for the degradation of damaged proteins and organelles within cells and helps maintain intracellular homeostasis. Imbalances in autophagy cause various pathological disorders. The current study investigated the role of several polyphenolic compounds, including tannic acid (TA), gallic acid (GA), and ellagic acid (EA) in the regulation of osteoclast differentiation of myeloid cells. We demonstrated that polyphenolic compounds inhibit osteoclast differentiation in a dose-dependent manner. Quantitative real-time PCR, immunocytochemistry, and western blotting revealed that osteoclast markers, such as NFATc1, Cathepsin K, and TRAP were inhibited after the addition of polyphenolic compounds during osteoclast differentiation. In our investigation into the molecular mechanisms, we found that the addition of polyphenolic compounds reduced the number of autophagic vesicles and the levels of LC3B, BECN1, ATG5, and ATG7 molecules through the inactivation of Akt, thus inhibiting the autophagy process. In addition, we found that by decreasing intracellular calcium and decreasing ROS levels, along with decreasing mitochondrial membrane potential, polyphenolic compounds inhibit osteoclast differentiation. Together, this study provides evidence that polyphenolic compounds inhibit osteoclast differentiation by reducing ROS production, autophagy, intracellular Ca2+ level, and mitochondrial membrane potentials.
Collapse
|
3
|
Hemp Seeds in Post-Arthroplasty Rehabilitation: A Pilot Clinical Study and an In Vitro Investigation. Nutrients 2021; 13:nu13124330. [PMID: 34959882 PMCID: PMC8709006 DOI: 10.3390/nu13124330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/26/2021] [Accepted: 11/27/2021] [Indexed: 11/20/2022] Open
Abstract
Osteoarthritis is a type of degenerative joint disease that results from the breakdown of joint cartilage and underlying bone. Due to their antioxidants and anti-inflammatory action, the phytochemical constituents of many vegetable varieties could represent a new frontier for the treatment of patients with Osteoarthritis and are still being explored. The aim of this pilot human study was to investigate the effects of pasta enriched with hemp seed flour on osteoarticular pain and bone formation markers in patients in post-arthroplasty rehabilitation. Another purpose was to evaluate the effect of hemp seed extract on bone metabolism, in vitro. A pilot, controlled, clinical study was conducted to verify the feasibility of pain symptom reduction in patients with Osteoarthritis undergoing arthroplasty surgery. We also investigated the effect of hemp seed extract on the Wnt/β-catenin and ERK1/2 pathways, alkaline phosphatase, RANKL, RUNX-2, osteocalcin, and COL1A on Saos-2. After 6 weeks, the consumption of hemp seed pasta led to greater pain relief compared to the regular pasta control group (−2.9 ± 1.3 cm vs. −1.3 ± 1.3 cm; p = 0.02). A significant reduction in serum BALP was observed in the participants consuming the hemp seed pasta compared to control group (−2.8 ± 3.2 µg/L vs. 1.1 ± 4.3 µg/L; p = 0.04). In the Saos-2 cell line, hemp seed extract also upregulated Wnt/β-catenin and Erk1/2 pathways (p = 0.02 and p = 0.03) and osteoblast differentiation markers (e.g., ALP, OC, RUNX2, and COL1A) and downregulated RANKL (p = 0.02), compared to the control. Our study demonstrated that hemp seed can improve pain symptoms in patients with osteoarthritis undergoing arthroplasty surgery and also improves bone metabolism both in humans and in vitro. However, more clinical studies are needed to confirm our preliminary findings.
Collapse
|
4
|
Cerqueni G, Scalzone A, Licini C, Gentile P, Mattioli-Belmonte M. Insights into oxidative stress in bone tissue and novel challenges for biomaterials. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2021; 130:112433. [PMID: 34702518 DOI: 10.1016/j.msec.2021.112433] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/08/2021] [Accepted: 09/11/2021] [Indexed: 12/28/2022]
Abstract
The presence of Reactive Oxygen Species (ROS) in bone can influence resident cells behaviour as well as the extra-cellular matrix composition and the tissue architecture. Aging, in addition to excessive overloads, unbalanced diet, smoking, predisposing genetic factors, lead to an increase of ROS and, if it is accompanied with an inappropriate production of scavengers, promotes the generation of oxidative stress that encourages bone catabolism. Furthermore, bone injuries can be triggered by numerous events such as road and sports accidents or tumour resection. Although bone tissue possesses a well-known repair and regeneration capacity, these mechanisms are inefficient in repairing large size defects and bone grafts are often necessary. ROS play a fundamental role in response after the implant introduction and can influence its success. This review provides insights on the mechanisms of oxidative stress generated by an implant in vivo and suitable ways for its modulation. The local delivery of active molecules, such as polyphenols, enhanced bone biomaterial integration evidencing that the management of the oxidative stress is a target for the effectiveness of an implant. Polyphenols have been widely used in medicine for cardiovascular, neurodegenerative, bone disorders and cancer, thanks to their antioxidant and anti-inflammatory properties. In addition, the perspective of new smart biomaterials and molecular medicine for the oxidative stress modulation in a programmable way, by the use of ROS responsive materials or by the targeting of selective molecular pathways involved in ROS generation, will be analysed and discussed critically.
Collapse
Affiliation(s)
- Giorgia Cerqueni
- Department of Clinical and Molecular Sciences (DISCLIMO), Università Politecnica delle Marche, Via Tronto 10/a, Ancona 60126, Italy
| | - Annachiara Scalzone
- School of Engineering, Newcastle University, Stephenson Building, Claremont Road, Newcastle upon Tyne NE1 7RU, UK
| | - Caterina Licini
- Department of Clinical and Molecular Sciences (DISCLIMO), Università Politecnica delle Marche, Via Tronto 10/a, Ancona 60126, Italy; Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 204, 10129 Torino, Italy
| | - Piergiorgio Gentile
- School of Engineering, Newcastle University, Stephenson Building, Claremont Road, Newcastle upon Tyne NE1 7RU, UK
| | - Monica Mattioli-Belmonte
- Department of Clinical and Molecular Sciences (DISCLIMO), Università Politecnica delle Marche, Via Tronto 10/a, Ancona 60126, Italy.
| |
Collapse
|
5
|
Jiang Y, Jiang Z, Ma L, Huang Q. Advances in Nanodelivery of Green Tea Catechins to Enhance the Anticancer Activity. Molecules 2021; 26:3301. [PMID: 34072700 PMCID: PMC8198522 DOI: 10.3390/molecules26113301] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/25/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022] Open
Abstract
Cancer is one of the leading causes of death globally. A variety of phenolic compounds display preventative and therapeutic effects against cancers. Green teas are rich in phenolics. Catechins are the most dominant phenolic component in green teas. Studies have shown that catechins have anticancer activity in various cancer models. The anticancer activity of catechins, however, may be compromised due to their low oral bioavailability. Nanodelivery emerges as a promising way to improve the oral bioavailability and anticancer activity of catechins. Research in this area has been actively conducted in recent decades. This review provides the molecular mechanisms of the anticancer effects of catechins, the factors that limit the oral bioavailability of catechins, and the latest advances of delivering catechins using nanodelivery systems through different routes to enhance their anticancer activity.
Collapse
Affiliation(s)
- Yike Jiang
- Shenzhen Bay Laboratory, Institute of Biomedical Health Technology and Engineering, Shenzhen 518132, China;
| | - Ziyi Jiang
- Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China;
- State Key Laboratory of Chemical Oncogenomics, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Lan Ma
- Shenzhen Bay Laboratory, Institute of Biomedical Health Technology and Engineering, Shenzhen 518132, China;
- Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China;
- State Key Laboratory of Chemical Oncogenomics, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Qingrong Huang
- Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ 08901, USA
| |
Collapse
|
6
|
Lin SY, Kang L, Wang CZ, Huang HH, Cheng TL, Huang HT, Lee MJ, Lin YS, Ho ML, Wang GJ, Chen CH. (-)-Epigallocatechin-3-Gallate (EGCG) Enhances Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells. Molecules 2018; 23:E3221. [PMID: 30563251 PMCID: PMC6321548 DOI: 10.3390/molecules23123221] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 11/08/2018] [Accepted: 11/14/2018] [Indexed: 01/08/2023] Open
Abstract
Osteoporosis is the second most-prevalent epidemiologic disease in the aging population worldwide. Cross-sectional and retrospective evidence indicates that tea consumption can mitigate bone loss and reduce risk of osteoporotic fractures. Tea polyphenols enhance osteoblastogenesis and suppress osteoclastogenesis in vitro. Previously, we showed that (-)-epigallocatechin-3-gallate (EGCG), one of the green tea polyphenols, increased osteogenic differentiation of murine bone marrow mesenchymal stem cells (BMSCs) by increasing the mRNA expression of osteogenesis-related genes, alkaline phosphatase activity and, eventually, mineralization. We also found that EGCG could mitigate bone loss and improve bone microarchitecture in ovariectomy-induced osteopenic rats, as well as enhancing bone defect healing partially via bone morphogenetic protein 2 (BMP2). The present study investigated the effects of EGCG in human BMSCs. We found that EGCG, at concentrations of both 1 and 10 µmol/L, can increase mRNA expression of BMP2, Runx2, alkaline phosphatase (ALP), osteonectin and osteocalcin 48 h after treatment. EGCG increased ALP activity both 7 and 14 days after treatment. Furthermore, EGCG can also enhance mineralization two weeks after treatment. EGCG without antioxidants also can enhance mineralization. In conclusion, EGCG can increase mRNA expression of BMP2 and subsequent osteogenic-related genes including Runx2, ALP, osteonectin and osteocalcin. EGCG further increased ALP activity and mineralization. Loss of antioxidant activity can still enhance mineralization of human BMSCs (hBMSCs).
Collapse
Affiliation(s)
- Sung-Yen Lin
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Departments of Orthopedics, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung 80415, Taiwan.
- Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
| | - Lin Kang
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70403, Taiwan.
| | - Chau-Zen Wang
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80701, Taiwan.
| | - Han Hsiang Huang
- Department of Veterinary Medicine, National Chiayi University, Chiayi 60054, Taiwan.
| | - Tsung-Lin Cheng
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
| | - Hsuan-Ti Huang
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Departments of Orthopedics, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung 80415, Taiwan.
| | - Mon-Juan Lee
- Department of Bioscience Technology, Chang Jung Christian University, Tainan 71101, Taiwan.
- Innovative Research Center of Medicine, Chang Jung Christian University, Tainan 71101, Taiwan.
| | - Yi-Shan Lin
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
| | - Mei-Ling Ho
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80701, Taiwan.
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.
| | - Gwo-Jaw Wang
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
| | - Chung-Hwan Chen
- Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Departments of Orthopedics, College of Medicine, Kaohsiung Medical University, Kaohsiung 80701, Taiwan.
- Department of Orthopedics, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung 80415, Taiwan.
| |
Collapse
|
7
|
Dunaway S, Odin R, Zhou L, Ji L, Zhang Y, Kadekaro AL. Natural Antioxidants: Multiple Mechanisms to Protect Skin From Solar Radiation. Front Pharmacol 2018; 9:392. [PMID: 29740318 PMCID: PMC5928335 DOI: 10.3389/fphar.2018.00392] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/05/2018] [Indexed: 12/13/2022] Open
Abstract
Human skin exposed to solar ultraviolet radiation (UVR) results in a dramatic increase in the production of reactive oxygen species (ROS). The sudden increase in ROS shifts the natural balance toward a pro-oxidative state, resulting in oxidative stress. The detrimental effects of oxidative stress occur through multiple mechanisms that involve alterations to proteins and lipids, induction of inflammation, immunosuppression, DNA damage, and activation of signaling pathways that affect gene transcription, cell cycle, proliferation, and apoptosis. All of these alterations promote carcinogenesis and therefore, regulation of ROS levels is critical to the maintenance of normal skin homeostasis. Several botanical products have been found to exhibit potent antioxidant capacity and the ability to counteract UV-induced insults to the skin. These natural products exert their beneficial effects through multiple pathways, including some known to be negatively affected by solar UVR. Aging of the skin is also accelerated by UVR exposure, in particular UVA rays that penetrate deep into the epidermis and the dermis where it causes the degradation of collagen and elastin fibers via oxidative stress and activation of matrix metalloproteinases (MMPs). Because natural compounds are capable of attenuating some of the UV-induced aging effects in the skin, increased attention has been generated in the area of cosmetic sciences. The focus of this review is to cover the most prominent phytoproducts with potential to mitigate the deleterious effects of solar UVR and suitability for use in topical application.
Collapse
Affiliation(s)
- Spencer Dunaway
- Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Rachel Odin
- Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Linli Zhou
- Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH, United States.,Division of Pharmaceutical Sciences, University of Cincinnati College of Pharmacy, Cincinnati, OH, United States
| | - Liyuan Ji
- Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH, United States.,Division of Pharmaceutical Sciences, University of Cincinnati College of Pharmacy, Cincinnati, OH, United States
| | - Yuhang Zhang
- Division of Pharmaceutical Sciences, University of Cincinnati College of Pharmacy, Cincinnati, OH, United States
| | - Ana L Kadekaro
- Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| |
Collapse
|
8
|
Suvarna V, Murahari M, Khan T, Chaubey P, Sangave P. Phytochemicals and PI3K Inhibitors in Cancer-An Insight. Front Pharmacol 2017; 8:916. [PMID: 29311925 PMCID: PMC5736021 DOI: 10.3389/fphar.2017.00916] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/30/2017] [Indexed: 12/11/2022] Open
Abstract
In today's world of modern medicine and novel therapies, cancer still remains to be one of the prime contributor to the death of people worldwide. The modern therapies improve condition of cancer patients and are effective in early stages of cancer but the advanced metastasized stage of cancer remains untreatable. Also most of the cancer therapies are expensive and are associated with adverse side effects. Thus, considering the current status of cancer treatment there is scope to search for efficient therapies which are cost-effective and are associated with lesser and milder side effects. Phytochemicals have been utilized for many decades to prevent and cure various ailments and current evidences indicate use of phytochemicals as an effective treatment for cancer. Hyperactivation of phosphoinositide 3-kinase (PI3K) signaling cascades is a common phenomenon in most types of cancers. Thus, natural substances targeting PI3K pathway can be of great therapeutic potential in the treatment of cancer patients. This chapter summarizes the updated research on plant-derived substances targeting PI3K pathway and the current status of their preclinical studies and clinical trials.
Collapse
Affiliation(s)
- Vasanti Suvarna
- Department of Pharmaceutical Chemistry and Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India
| | - Manikanta Murahari
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, M.S Ramaiah University of Applied Sciences, Bangalore, India
| | - Tabassum Khan
- Department of Pharmaceutical Chemistry and Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India
| | - Pramila Chaubey
- Department of Pharmaceutics, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India
| | - Preeti Sangave
- Department of Pharmaceutical Sciences, School of Pharmacy and Technology Management, SVKM's NMIMS, Mumbai, India
| |
Collapse
|
9
|
Sharma P, Montes de Oca MK, Alkeswani AR, McClees SF, Das T, Elmets CA, Afaq F. Tea polyphenols for the prevention of UVB-induced skin cancer. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2017; 34:50-59. [PMID: 29044724 DOI: 10.1111/phpp.12356] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/30/2017] [Indexed: 12/16/2022]
Abstract
Skin cancer is the most common type of cancer with increasing incidence rate and public health burden. Solar ultraviolet (UV) radiation causes an array of damaging cellular and molecular events that eventually lead to the development of skin cancer. Despite increased awareness about sun protection, the exposure rate remains high with less than 15% of men and 30% of women using sunscreen on a regular basis. Therefore, there is an imperative need for the development of novel preventive approaches. Skin cancer chemoprevention using phytochemicals either as dietary supplements or by topical applications has gained considerable attention due to their low toxicity, availability, and anticarcinogenic properties. Tea, the second most commonly consumed beverage in the world, is a rich source of promising phytochemicals known as polyphenols. In this review, we discuss the findings of various in vitro, in vivo and human studies signifying the chemopreventive effects of tea polyphenols against UVB-induced skin cancer. This is accomplished by exploring the role of tea polyphenols in DNA repair, inflammation, oxidative stress, signaling pathways, and epigenetics. Finally, this review discusses a variety of innovative delivery methods that enhance the photochemopreventive effects of tea polyphenols against skin cancer.
Collapse
Affiliation(s)
- Pooja Sharma
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mary K Montes de Oca
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Amena R Alkeswani
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Sarah F McClees
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Tanushree Das
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Craig A Elmets
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA.,Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Farrukh Afaq
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA.,Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
10
|
Tominari T, Ichimaru R, Yoshinouchi S, Matsumoto C, Watanabe K, Hirata M, Grundler FMW, Inada M, Miyaura C. Effects of O-methylated (-)-epigallocatechin gallate (EGCG) on LPS-induced osteoclastogenesis, bone resorption, and alveolar bone loss in mice. FEBS Open Bio 2017; 7:1972-1981. [PMID: 29226083 PMCID: PMC5715342 DOI: 10.1002/2211-5463.12340] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/30/2017] [Accepted: 10/19/2017] [Indexed: 01/16/2023] Open
Abstract
(−)‐Epigallocatechin‐3‐O‐gallate (EGCG), present in green tea, exhibits antioxidant and antiallergy effects. EGCG3″Me, a 3‐O‐methylated derivative of EGCG, has been reported to show similar biological functions; the inhibitory activity of EGCG3″Me in a mouse allergy model was more potent than that of EGCG, probably due to the efficiency of absorption from the intestine. However, the functional potency of these EGCGs is controversial in each disease model. We previously observed that EGCG suppressed inflammatory bone resorption and prevented alveolar bone loss in a mouse model of periodontosis. In this study, we examined the role of EGCG3″Me in bone resorption using a mouse model of periodontitis. Lipopolysaccharide (LPS)‐induced osteoclast formation was suppressed by adding EGCG3″Me to cocultures of osteoblasts and bone marrow cells, and LPS‐induced bone resorption was also inhibited by EGCG3″Me in calvarial organ cultures. EGCG3″Me acted on osteoblasts and suppressed prostaglandin E (PGE) production, which is critical for inflammatory bone resorption, by inhibiting the expression of COX‐2 and mPGES‐1, key enzymes for PGE synthesis. In osteoclast precursor macrophages, EGCG3″Me suppressed RANKL‐dependent differentiation into mature osteoclasts. In a mouse model of periodontitis, LPS‐induced bone resorption was suppressed by EGCG3″Me in organ culture of mouse alveolar bone, and the alveolar bone loss was further attenuated by the treatment of EGCG3″Me in the lower gingiva in vivo. EGCG3″Me may be a potential natural compound for the protection of inflammatory bone loss in periodontitis.
Collapse
Affiliation(s)
- Tsukasa Tominari
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan
| | - Ryota Ichimaru
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan
| | - Shosei Yoshinouchi
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan
| | - Chiho Matsumoto
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan
| | - Kenta Watanabe
- Institute of Global Innovation Research Tokyo University of Agriculture and Technology Koganei Japan
| | - Michiko Hirata
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan
| | | | - Masaki Inada
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan.,Institute of Global Innovation Research Tokyo University of Agriculture and Technology Koganei Japan
| | - Chisato Miyaura
- Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Koganei Japan.,Institute of Global Innovation Research Tokyo University of Agriculture and Technology Koganei Japan
| |
Collapse
|
11
|
Torre E. Molecular signaling mechanisms behind polyphenol-induced bone anabolism. PHYTOCHEMISTRY REVIEWS : PROCEEDINGS OF THE PHYTOCHEMICAL SOCIETY OF EUROPE 2017; 16:1183-1226. [PMID: 29200988 PMCID: PMC5696504 DOI: 10.1007/s11101-017-9529-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 08/20/2017] [Indexed: 05/08/2023]
Abstract
For millennia, in the different cultures all over the world, plants have been extensively used as a source of therapeutic agents with wide-ranging medicinal applications, thus becoming part of a rational clinical and pharmacological investigation over the years. As bioactive molecules, plant-derived polyphenols have been demonstrated to exert many effects on human health by acting on different biological systems, thus their therapeutic potential would represent a novel approach on which natural product-based drug discovery and development could be based in the future. Many reports have provided evidence for the benefits derived from the dietary supplementation of polyphenols in the prevention and treatment of osteoporosis. Polyphenols are able to protect the bone, thanks to their antioxidant properties, as well as their anti-inflammatory actions by involving diverse signaling pathways, thus leading to bone anabolic effects and decreased bone resorption. This review is meant to summarize the research works performed so far, by elucidating the molecular mechanisms of action of polyphenols in a bone regeneration context, aiming at a better understanding of a possible application in the development of medical devices for bone tissue regeneration.
Collapse
Affiliation(s)
- Elisa Torre
- Nobil Bio Ricerche srl, Via Valcastellana, 26, 14037 Portacomaro, AT Italy
| |
Collapse
|
12
|
Tanaka S, Furuya K, Yamamoto K, Yamada K, Ichikawa M, Suda M, Makabe H. Procyanidin B2 gallates inhibit IFN-γ and IL-17 production in T cells by suppressing T-bet and RORγt expression. Int Immunopharmacol 2017; 44:87-96. [DOI: 10.1016/j.intimp.2017.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 12/26/2016] [Accepted: 01/06/2017] [Indexed: 01/15/2023]
|
13
|
Liu X, Yao Z. Chronic over-nutrition and dysregulation of GSK3 in diseases. Nutr Metab (Lond) 2016; 13:49. [PMID: 27493677 PMCID: PMC4972972 DOI: 10.1186/s12986-016-0108-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/21/2016] [Indexed: 12/16/2022] Open
Abstract
Loss of cellular response to hormonal regulation in maintaining metabolic homeostasis is common in the process of aging. Chronic over-nutrition may render cells insensitive to such a hormonal regulation owing to overstimulation of certain signaling pathways, thus accelerating aging and causing diseases. The glycogen synthase kinase 3 (GSK3) plays a pivotal role in relaying various extracellular and intracellular regulatory signals critical to cell growth, survival, regeneration, or death. The main signaling pathway regulating GSK3 activity through serine-phosphorylation is the phosphoinositide 3-kinase (PI3K)/phosphoinositide-dependent kinase-1 (PDK1)/Akt relay that catalyzes serine-phosphorylation and thus inactivation of GSK3. In addition, perilipin 2 (PLIN2) has recently been shown to regulate GSK3 activation through direct association with GSK3. This review summarizes current understanding on environmental and nutritional factors contributing to GSK3 regulation (or dysregulation) through the PI3K/PDK1/Akt/GSK3 axis, and highlights the newly discovered role that PLIN2 plays in regulating GSK3 activity and GSK3 downstream pathways.
Collapse
Affiliation(s)
- Xunxian Liu
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5 Canada
| | - Zemin Yao
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5 Canada
| |
Collapse
|
14
|
Forbes-Hernández TY, Giampieri F, Gasparrini M, Mazzoni L, Quiles JL, Alvarez-Suarez JM, Battino M. The effects of bioactive compounds from plant foods on mitochondrial function: a focus on apoptotic mechanisms. Food Chem Toxicol 2014; 68:154-82. [PMID: 24680691 DOI: 10.1016/j.fct.2014.03.017] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/09/2014] [Accepted: 03/14/2014] [Indexed: 02/06/2023]
Abstract
Mitochondria are essential organelles for cellular integrity and functionality maintenance and their imparement is implicated in the development of a wide range of diseases, including metabolic, cardiovascular, degenerative and hyperproliferative pathologies. The identification of different compounds able to interact with mitochondria for therapeutic purposes is currently becoming of primary importance. Indeed, it is well known that foods, particularly those of vegetable origin, present several constituents with beneficial effects on health. This review summarizes and updates the most recent findings concerning the mechanisms through which different dietary compounds from plant foods affect mitochondria functionality in healthy and pathological in vitro and in vivo models, paying particular attention to the pathways involved in mitochondrial biogenesis and apoptosis.
Collapse
Affiliation(s)
- Tamara Y Forbes-Hernández
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Facoltà di Medicina, Università Politecnica delle Marche, Italy
| | - Francesca Giampieri
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, Italy.
| | - Massimiliano Gasparrini
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Facoltà di Medicina, Università Politecnica delle Marche, Italy
| | - Luca Mazzoni
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Facoltà di Medicina, Università Politecnica delle Marche, Italy
| | - José L Quiles
- Department of Physiology, Institute of Nutrition and Food Technology "José Mataix", Biomedical Research Center, University of Granada, Spain
| | - José M Alvarez-Suarez
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Facoltà di Medicina, Università Politecnica delle Marche, Italy; Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, Italy
| | - Maurizio Battino
- Dipartimento di Scienze Cliniche Specialistiche ed Odontostomatologiche, Sez. Biochimica, Facoltà di Medicina, Università Politecnica delle Marche, Italy.
| |
Collapse
|
15
|
Yoon JY, Kwon HH, Min SU, Thiboutot DM, Suh DH. Epigallocatechin-3-Gallate Improves Acne in Humans by Modulating Intracellular Molecular Targets and Inhibiting P. acnes. J Invest Dermatol 2013; 133:429-40. [DOI: 10.1038/jid.2012.292] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
16
|
Mak JCW. Potential role of green tea catechins in various disease therapies: progress and promise. Clin Exp Pharmacol Physiol 2012; 39:265-73. [PMID: 22229384 DOI: 10.1111/j.1440-1681.2012.05673.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Green tea (from the plant Camellia sinensis), a beverage whose consumption started 5000 years ago in China, has important biological and pharmacological properties. The beneficial effects of green tea have been attributed to the presence of phenolic compounds that are powerful anti-oxidants and free iron scavengers. Of all the catechins found in green tea, namely (-)-epicatechin-3-gallate, (-)-epigallocatechin, (-)-epicatechin and (-)-epigallocatechin-3-gallate (EGCG), EGCG is the most abundant and powerful. It is widely believed that green tea may protect against death from all causes, especially cardiovascular diseases (coronary heart disease and stroke) owing to the presence of catechins associated with green tea consumption. Other health benefits include various types of cancer chemoprevention, weight loss and protective effects against neurodegenerative diseases (Alzheimer's disease and Parkinson's disease). Thus far, numerous pharmacological activities regulating disease-specific molecular targets have been reported in vitro for EGCG concentrations in the micromolar range, which are physiologically irrelevant. Although most of the studies have shown benefits with two to three cups of green tea per day, the optimal dose has not yet been established to enable any solid conclusions to be drawn regarding the various health benefits of green tea or its constituents in humans. With Phase I trials providing information on the safety profile and pharmacokinetics of EGCG, the window of opportunity is wider to undertake well-controlled long-term human studies to enable a full understanding of the protective effects of green tea catechins on various parameters in different settings.
Collapse
Affiliation(s)
- Judith C W Mak
- Departments of Medicine and Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China.
| |
Collapse
|
17
|
Kumar G, Dange P, Kailaje V, Vaidya MM, Ramchandani AG, Maru GB. Polymeric black tea polyphenols modulate the localization and activity of 12-O-tetradecanoylphorbol-13-acetate-mediated kinases in mouse skin: mechanisms of their anti-tumor-promoting action. Free Radic Biol Med 2012; 53:1358-70. [PMID: 22841871 DOI: 10.1016/j.freeradbiomed.2012.07.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 07/05/2012] [Accepted: 07/17/2012] [Indexed: 02/06/2023]
Abstract
Polymeric black tea polyphenols (PBPs) have been shown to possess anti-tumor-promoting effects in two-stage skin carcinogenesis. However, their mechanisms of action are not fully elucidated. In this study, mechanisms of PBP-mediated antipromoting effects were investigated in a mouse model employing the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Compared to controls, a single topical application of TPA to mouse skin increased the translocation of protein kinase C (PKC) from cytosol to membrane. Pretreatment with PBPs 1-3 decreased TPA-induced translocation of PKC isozymes (α, β, η, γ, ε) from cytosol to membrane, whereas PBPs 4 and 5 were less effective. The levels of PKCs δ and ζ in cytosol/membrane were similar in all the treatment groups. Complementary confocal microscopic evaluation showed a decrease in TPA-induced PKCα fluorescence in PBP-3-pretreated membranes, whereas pretreatment with PBP-5 did not show a similar decrease. Based on the experiments with specific enzyme inhibitors and phosphospecific antibodies, both PBP-3 and PBP-5 were observed to decrease TPA-induced level and/or activity of phosphatidylinositol 3-kinase (PI3K) and AKT1 (pS473). An additional ability of PBP-3 to inhibit site-specific phosphorylation of PKCα at all three positions responsible for its activation [PKCα (pT497), PKC PAN (βII pS660), PKCα/βII (pT638/641)] and AKT1 at the Thr308 position, along with a decrease in TPA-induced PDK1 protein level, correlated with the inhibition of translocation of PKC, which may impart relatively stronger chemoprotective activity to PBP-3 than to PBP-5. Altogether, PBP-mediated decrease in TPA-induced PKC phosphorylation correlated well with decreased TPA-induced NF-κB phosphorylation and downstream target proteins associated with proliferation, apoptosis, and inflammation in mouse skin. Results suggest that the antipromoting effects of PBPs are due to modulation of TPA-induced PI3K-mediated signal transduction.
Collapse
Affiliation(s)
- Gaurav Kumar
- Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Kharghar, Navi Mumbai 410210, India
| | | | | | | | | | | |
Collapse
|
18
|
He Z, Cui P, Ye C, Ma WY, Bode A, Dong Z. Analysis of the role of p38 MAP kinase in epidermal growth factor-induced JB6 Cl41 cell transformation by cDNA array. Gene 2012; 497:71-8. [PMID: 22301268 DOI: 10.1016/j.gene.2011.12.054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2011] [Revised: 11/28/2011] [Accepted: 12/22/2011] [Indexed: 12/01/2022]
Abstract
To further explore the mechanism of p38 MAP kinase in regulation of JB6 Cl41 cell transformation. cDNA array was employed to scan the differential expression genes between DN-p38 cells and CMV-neo JB6 Cl41 cells after EGF stimuli. We found that up-expression genes including oncogenes and tumor suppressor genes, p53-associated protein, transcription repressors, apoptosis-associated genes, and growth arrest and DNA damage-inducible protein 153 were detected in DN-p38 cells, but low expression in CMV-neo JB6 Cl41 cells after EGF treatment. Meanwhile, some proto-oncogenes, such as c-Myc, and signal transducer and activator of transcription 1 (STAT1) were lowly expressed in EGF-stimulated DN-p38 cells, but had relatively high expression level in CMV-neo JB6 Cl41 cells under the same stimuli. Four of the differential expression genes were further confirmed by quantitative RT-PCR analysis. Our results indicate that p38 MAP kinase is involved in EGF-induced JB6 Cl41 cell transformation through effecting on more genes expression levels including transcription factors, proto-oncogene, apoptosis-related genes and growth arrest genes.
Collapse
Affiliation(s)
- Zhiwei He
- China-America Cancer Research Institute, Guangdong Medical College, Dongguan 523808, PR China.
| | | | | | | | | | | |
Collapse
|
19
|
Abstract
The incidence of nonmelanoma skin cancer is increasing every year. Basal cell carcinoma and squamous cell carcinoma are the two major types of nonmelanoma skin cancer. Among other factors, understanding the potential role of nutrients in the development, progression, and treatment of nonmelanoma skin cancer is critical. This contribution provides a review of the nutrients that have been more extensively investigated in the literature with regard to nonmelanoma skin cancer, including dietary fats, retinol, carotenoids, vitamin C, vitamin D, vitamin E, selenium, copper, iron, zinc, green tea, and black tea.
Collapse
Affiliation(s)
- Michael J Payette
- Department of Dermatology, MC-6230, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA
| | | | | |
Collapse
|
20
|
Yu PL, Pu HF, Chen SY, Wang SW, Wang PS. Effects of catechin, epicatechin and epigallocatechin gallate on testosterone production in rat leydig cells. J Cell Biochem 2010; 110:333-42. [PMID: 20432242 DOI: 10.1002/jcb.22541] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Catechins have been reported to have many pharmacological properties such as the effects of anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-ultraviolet, and reduction of blood pressure as well as glucose and cholesterol levels. However, the effect of catechins on the reproductive mechanism is still unknown. In the present study, the effects of catechins on testosterone secretion in rat testicular Leydig cells (LCs) were explored. Both in vivo and in vitro investigations were performed. Purified LCs were incubated with or without catechin (CCN), epicatechin (EC), epigallocatechin gallate (EGCG, 10(-10)-10(-8) M) under challenge with human chorionic gonadotropin (hCG, 0.01 IU/ml), forskolin, SQ22536 (an adenylyl cyclase inhibitor), 8-bromo-adenosine 3':5'-cyclic monophosphate (8-Br-cAMP), A23187 (a calcium ionophore), and nifedipine (10(-5) M), respectively. To study the effects of catechins on steroidogenesis, steroidogenic precursors-stimulated testosterone release was examined. The functions of the steroidogenic enzymes including protein expression of cytochrome P450 side chain cleavage enzyme (P450scc) and steroidogenic acute regulatory (StAR) protein were investigated and expressed by Western blotting. Catechins increased plasma testosterone in vivo in male rats. In vitro, low-dose concentration of catechins increased gonadotropin releasing hormone (GnRH)-stimulated luteinizing hormone (LH) release by anterior pituitary gland and hCG-stimulated testosterone release by LCs of male rats. These results suggested that catechins stimulated testosterone production by acting on rat LCs via the mechanism of increasing the action of cAMP, but not P450scc, StAR protein or the activity of intracellular calcium. EC, one of the catechins increased the testosterone secretion by rat LCs via the enzyme activities of 17beta-hydroxysteroid dehydrogenase (17beta-HSD).
Collapse
Affiliation(s)
- Po-Ling Yu
- Department of Surgery, Taipei City Hospital, Taipei, Taiwan, Republic of China
| | | | | | | | | |
Collapse
|
21
|
Cocoa polyphenols suppress TNF-α-induced vascular endothelial growth factor expression by inhibiting phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase kinase-1 (MEK1) activities in mouse epidermal cells. Br J Nutr 2010; 104:957-64. [PMID: 20550744 DOI: 10.1017/s0007114510001704] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cocoa polyphenols have antioxidant and anti-inflammatory effects. TNF-α is a pro-inflammatory cytokine that has a vital role in the pathogenesis of inflammatory diseases such as cancer and psoriasis. Vascular endothelial growth factor (VEGF) expression is associated with tumorigenesis, CVD, rheumatoid arthritis and psoriasis. We tested whether cocoa polyphenol extract (CPE) inhibited TNF-α-induced VEGF expression in promotion-sensitive JB6 mouse epidermal cells. CPE significantly inhibited TNF-α-induced up-regulation of VEGF via reducing TNF-α-induced activation of the nuclear transcription factors activator protein-1 (AP-1) and NF-κB, which are key regulators of VEGF expression. CPE also inhibited TNF-α-induced phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase. CPE blocked activation of their downstream kinases, p70 kDa ribosomal protein S6 kinase and p90 kDa ribosomal protein S6 kinase. CPE suppressed phosphoinositide 3-kinase (PI3K) activity via binding PI3K directly. CPE did not affect TNF-α-induced phosphorylation of mitogen-activated protein kinase kinase-1 (MEK1) but suppressed TNF-α-induced MEK1 activity. Collectively, these results indicate that CPE reduced TNF-α-induced up-regulation of VEGF by directly inhibiting PI3K and MEK1 activities, which may contribute to its chemopreventive potential.
Collapse
|
22
|
Akt is a direct target for myricetin to inhibit cell transformation. Mol Cell Biochem 2009; 332:33-41. [PMID: 19504174 DOI: 10.1007/s11010-009-0171-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Accepted: 05/21/2009] [Indexed: 10/20/2022]
Abstract
Akt, a serine/threonine kinase, is a critical regulator in many cellular processes including cell growth, proliferation, and apoptosis. In this study, we found that myricetin, a typical flavonol existing in many fruits and vegetables, could directly target Akt to inhibit cell transformation. Binding assay revealed that myricetin bound to Akt directly by competing with ATP. In vitro and ex vivo data confirmed that myricetin inhibited the phosphorylation and kinase activity of Akt. Molecular modeling suggested that myricetin easily docks to the ATP-binding site of Akt with hydrogen bonds. Signaling analysis data further demonstrated that myricetin inhibited Akt-mediated activator protein-1 (AP-1) transactivation, cyclin D1 expression and cell transformation. Overall, our results indicate that Akt is a direct target for myricetin to inhibit cell transformation.
Collapse
|
23
|
Bode AM, Dong Z. Epigallocatechin 3-gallate and green tea catechins: United they work, divided they fail. Cancer Prev Res (Phila) 2009; 2:514-7. [PMID: 19470792 DOI: 10.1158/1940-6207.capr-09-0083] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Ann M Bode
- The Hormel Institute, Austin, Minnesota 55912, USA
| | | |
Collapse
|
24
|
Bode A, Dong Z. Modulation of Cell Signal Transduction by Tea and Ginger. OXIDATIVE STRESS AND DISEASE 2008. [DOI: 10.1201/9780849381492.ch2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
|
25
|
Nomura M, Takahashi T, Nagata N, Tsutsumi K, Kobayashi S, Akiba T, Yokogawa K, Moritani S, Miyamoto KI. Inhibitory mechanisms of flavonoids on insulin-stimulated glucose uptake in MC3T3-G2/PA6 adipose cells. Biol Pharm Bull 2008; 31:1403-9. [PMID: 18591783 DOI: 10.1248/bpb.31.1403] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We assessed the effects of different classes of flavonoids on insulin-stimulated 2-deoxy-D-[1-(3)H]glucose uptake by mouse MC3T3-G2/PA6 cells differentiated into mature adipose cells. Among the flavonoids examined, the flavones, apigenin and luteolin, the flavonols, kaempferol, quercetin and fisetin, an isoflavone, genistein, a flavanonol, silybin, and the flavanols, (-)-epigallocatechin gallate (EGCG) and theaflavins, significantly inhibited insulin-stimulated glucose uptake. Key structural features of flavonoids for inhibition of insulin-stimulated glucose uptake are the B-ring 4'- or 3',4'-OH group and the C-ring C2-C3 double bond of the flavones and flavonols, the A-ring 5-OH of isoflavones, and the galloyl group of EGCG and theaflavins. Luteolin significantly inhibits insulin-stimulated phosphorylation of insulin receptor-beta subunit (IR-beta), and apigenin, kaempferol, quercetin and fisetin, also tended to inhibit the IR-beta phosphorylation. On the other hand, isoflavones, flavanols or flavanonols did not affect insulin-stimulated IR-beta phosphorylation. Apigenin, luteolin, kaempferol, quercetin and fisetin also appeared to inhibit insulin-stimulated activation of Akt, a pivotal downstream effector of phosphatidylinositol 3-kinase (PI3K), and suppressed insulin-dependent translocation of a glucose transporter, (GLUT)4, into the plasma membrane. Although genistein, silybin, EGCG and theaflavins had no effect on the insulin-stimulated activation of Akt, they blocked insulin-dependent GLUT4 translocation. These results provide novel insights into the modulation by flavonoids of insulin's actions, including glucose uptake in adipocytes.
Collapse
Affiliation(s)
- Masaaki Nomura
- Department of Clinical Pharmacology, Faculty of Pharmaceutical Sciences, Hokuriku University, Kanazawa, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Mnich CD, Hoek KS, Virkki LV, Farkas A, Dudli C, Laine E, Urosevic M, Dummer R. Green tea extract reduces induction of p53 and apoptosis in UVB-irradiated human skin independent of transcriptional controls. Exp Dermatol 2008; 18:69-77. [PMID: 18631247 DOI: 10.1111/j.1600-0625.2008.00765.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Ultraviolet (UV) irradiation plays a pivotal role in human skin carcinongenesis. Preclinically, systemically and topically applied green tea extract (GTE) has shown reduction of UV-induced (i) erythema, (ii) DNA damage, (iii) formation of radical oxygen species and (iv) downregulation of numerous factors related to apoptosis, inflammation, differentiation and carcinogenesis. In humans, topical GTE has so far only been tested in limited studies, with usually very high GTE concentrations and over short periods of time. Both chemical stability of GTE and staining properties of highly concentrated green tea polyphenols limit the usability of highly concentrated green tea extracts in cosmetic products. The present study tested the utility of stabilized low-dose GTE as photochemopreventive agents under everyday conditions. We irradiated with up to 100 mJ/cm(2) of UVB light skin patches which were pretreated with either OM24-containing lotion or a placebo lotion. Biopsies were taken from both irradiated and un-irradiated skin for both immunohistochemistry and DNA microarray analysis. We found that while OM24 treatment did not significantly affect UV-induced erythema and thymidine dimer formation, OM24 treatment significantly reduced UV-induced p53 expression in keratinocytes. We also found that OM24 treatment significantly reduced the number of apoptotic keratinocytes (sunburn cells and TUNEL-positive cells). Carefully controlled DNA microarray analyses showed that OM24 treatment does not induce off-target changes in gene expression, reducing the likelihood of unwanted side-effects. Topical GTE (OM24) reduces UVB-mediated epithelial damage already at low, cosmetically usable concentrations, without tachyphylaxis over 5 weeks, suggesting GTE as suitable everyday photochemopreventive agents.
Collapse
Affiliation(s)
- Christian D Mnich
- Department of Dermatology, University Hospital of Zurich, Zurich, Switzerland
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Wunderlich L, Paragh G, Wikonkál NM, Bánhegyi G, Kárpáti S, Mandl J. UVB induces a biphasic response of HIF-1α in cultured human keratinocytes. Exp Dermatol 2008; 17:335-42. [DOI: 10.1111/j.1600-0625.2007.00640.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
28
|
Adhami VM, Syed DN, Khan N, Afaq F. Phytochemicals for Prevention of Solar Ultraviolet Radiation-induced Damages. Photochem Photobiol 2008; 84:489-500. [DOI: 10.1111/j.1751-1097.2007.00293.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
29
|
Howells LM, Moiseeva EP, Neal CP, Foreman BE, Andreadi CK, Sun YY, Hudson EA, Manson MM. Predicting the physiological relevance of in vitro cancer preventive activities of phytochemicals. Acta Pharmacol Sin 2007; 28:1274-304. [PMID: 17723163 DOI: 10.1111/j.1745-7254.2007.00690.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
There is growing interest in the ability of phytochemicals to prevent chronic diseases, such as cancer and heart disease. However, some of these agents have poor bioavailability and many of the in-depth studies into their mechanisms of action have been carried out in vitro using doses which are unachievable in humans. In order to optimize the design of chemopreventive treatment, it is important to determine which of the many reported mechanisms of action are clinically relevant. In this review we consider the physiologically achievable doses for a few of the best studied agents (indole-3-carbinol, diindolylmethane, curcumin, epigallocatechin-3-gallate and resveratrol) and summarize the data derived from studies using these low concentrations in cell culture. We then cite examples of in vitro effects which have been observed in vivo. Finally, the ability of agent combinations to act synergistically or antagonistically is considered. We conclude that each of the compounds shows an encouraging range of activities in vitro at concentrations which are likely to be physiologically relevant. There are also many examples of in vivo studies which validate in vitro observations. An important consideration is that combinations of agents can result in significant activity at concentrations where any single agent is inactive. Thus, for each of the compounds reviewed here, in vitro studies have provided useful insights into their mechanisms of action in humans. However, data are lacking on the full range of activities at low doses in vitro and the benefits or otherwise of combinations in vivo.
Collapse
Affiliation(s)
- Lynne M Howells
- Cancer Biomarkers and Prevention Group, University of Leicester, Leicester LE1 7RH, UK
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Ichimatsu D, Nomura M, Nakamura S, Moritani S, Yokogawa K, Kobayashi S, Nishioka T, Miyamoto KI. Structure-activity relationship of flavonoids for inhibition of epidermal growth factor-induced transformation of JB6 Cl 41 cells. Mol Carcinog 2007; 46:436-45. [PMID: 17219438 DOI: 10.1002/mc.20292] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We found that quercetin, myricetin, quercetagetin, fisetin, (-)-epigallocatechin gallate (EGCG), and theaflavins, among 24 flavonoids examined, markedly inhibited epidermal growth factor (EGF)-induced cell transformation of mouse epidermal JB6 Cl 41 cells. The six flavonoids suppressed the EGF-induced activation of activator protein 1 (AP-1). In addition, myricetin, quercetagetin, EGCG, and theaflavins directly inhibited EGF-induced phosphatidylinositol 3-kinase (PI3K) activation. The important structural features of flavonoids for cell transformation-inhibitory activity are 3'- and 4'-OH on the B-ring, 3-OH on the C-ring, C2=C3 double bond in the C-ring, and the phenylchromone (C6-C5-C6) skeleton in the flavonols, and the galloyl group in EGCG and theaflavins. Our results provide new insight into possible mechanisms of the anti-carcinogenic effects of flavonoids, and could help to provide a basis for the design of novel cancer chemopreventive agents.
Collapse
Affiliation(s)
- Daisuke Ichimatsu
- Department of Hospital Pharmacy, School of Medicine, Kanazawa University, Kanazawa, Japan
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Yusuf N, Irby C, Katiyar SK, Elmets CA. Photoprotective effects of green tea polyphenols. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2007; 23:48-56. [PMID: 17254040 DOI: 10.1111/j.1600-0781.2007.00262.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Non-melanoma skin cancer is the most common malignancy in humans and is equivalent to the incidence of malignancies in all other organs combined in the United States. Current methods of prevention depend on sunscreens in humans, efficacy of which is largely undetermined for non-melanoma skin cancers. Green tea polyphenols have the greatest effect with respect to chemoprevention and have been found to be most potent at suppressing the carcinogenic activity of UV radiation. They protect against many of the other damaging effects of UV radiation such as UV-induced sunburn response, UV-induced immunosuppression and photoaging of the skin. They exert their photoprotective effects by various cellular, molecular and biochemical mechanisms in in vitro and in vivo systems. Green tea polyphenols thus have the potential, when used in conjunction with traditional sunscreens, to further protect the skin against the adverse effects of ultraviolet radiation.
Collapse
Affiliation(s)
- Nabiha Yusuf
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | | | | | | |
Collapse
|
32
|
Song L, Li J, Ye J, Yu G, Ding J, Zhang D, Ouyang W, Dong Z, Kim SO, Huang C. p85alpha acts as a novel signal transducer for mediation of cellular apoptotic response to UV radiation. Mol Cell Biol 2007; 27:2713-31. [PMID: 17242187 PMCID: PMC1899908 DOI: 10.1128/mcb.00657-06] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Apoptosis is an important cellular response to UV radiation (UVR), but the corresponding mechanisms remain largely unknown. Here we report that the p85alpha regulatory subunit of phosphatidylinositol 3-kinase (PI-3K) exerted a proapoptotic role in response to UVR through the induction of tumor necrosis factor alpha (TNF-alpha) gene expression. This special effect of p85alpha was unrelated to the PI-3K-dependent signaling pathway. Further evidence demonstrated that the inducible transcription factor NFAT3 was the major downstream target of p85alpha for the mediation of UVR-induced apoptosis and TNF-alpha gene transcription. p85alpha regulated UVR-induced NFAT3 activation by modulation of its nuclear translocation and DNA binding and the relevant transcriptional activities. Gel shift assays and site-directed mutagenesis allowed the identification of two regions in the TNF-alpha gene promoter that served as the NFAT3 recognition sequences. Chromatin immunoprecipitation assays further confirmed that the recruitment of NFAT3 to the endogenous TNF-alpha promoter was regulated by p85alpha upon UVR exposure. Finally, the knockdown of the NFAT3 level by its specific small interfering RNA decreased UVR-induced TNF-alpha gene transcription and cell apoptosis. The knockdown of endogenous p85alpha blocked NFAT activity and TNF-alpha gene transcription, as well as cell apoptosis. Thus, we demonstrated p85alpha-associated but PI-3K-independent cell death in response to UVR and identified a novel p85alpha/NFAT3/TNF-alpha signaling pathway for the mediation of cellular apoptotic responses under certain stress conditions such as UVR.
Collapse
Affiliation(s)
- Lun Song
- Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Abstract
Carcinogenesis is a multistage process consisting of initiation, promotion, and progression stages and each stage may be a possible target for chemopreventive agents. A significant outcome of these investigations on the elucidation of molecular and cellular mechanisms is the explication of signal transduction pathways induced by tumor promoters in cancer development. The current belief today is that cancer may be prevented or treated by targeting specific cancer genes, signaling proteins, and transcription factors. The molecular mechanisms explaining how normal cells undergo neoplastic transformation induced by tumor promoters are rapidly being clarified. Accumulating research evidence suggests that many of dietary factors, including tea compounds, may be used alone or in combination with traditional chemotherapeutic agents to prevent or treat cancer. The potential advantage of many natural or dietary compounds seems to focus on their potent anticancer activity combined with low toxicity and very few adverse side effects. This review summarizes some of our recent work regarding the effects of the various tea components on signal transduction pathways involved in neoplastic cell transformation and carcinogenesis.
Collapse
Affiliation(s)
- Ann M Bode
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
| | | |
Collapse
|
34
|
Lin JK, Lin-Shiau SY. Mechanisms of hypolipidemic and anti-obesity effects of tea and tea polyphenols. Mol Nutr Food Res 2006; 50:211-7. [PMID: 16404708 DOI: 10.1002/mnfr.200500138] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Among the health-promoting effects of tea and tea polyphenols, the cancer-chemopreventive effects in various animal model systems have been intensively investigated; meanwhile, the hypolipidemic and antiobesity effects in animals and humans have also become a hot issue for molecular nutrition and food research. It has been demonstrated that the body weights of rats and their plasma triglyceride, cholesterol, and LDL-cholesterol have been significantly reduced by feedings of oolong, black, pu-erh, and green tea leaves to the animals. It has been suggested that the inhibition of growth and suppression of lipogenesis in MCF-7 breast cancer cells may be through down-regulation of fatty acid synthase gene expression in the nucleus and stimulation of cell energy expenditure in the mitochondria. The experimental data indicated that the molecular mechanisms of fatty acid synthase gene suppression by tea polyphenols (EGCG, theaflavins) may invite down-regulation of EGFR/PI3K/Akt/Sp-1 signal transduction pathways.
Collapse
Affiliation(s)
- Jen-Kun Lin
- Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | | |
Collapse
|
35
|
Camouse MM, Hanneman KK, Conrad EP, Baron ED. Protective effects of tea polyphenols and caffeine. Expert Rev Anticancer Ther 2006; 5:1061-8. [PMID: 16336097 DOI: 10.1586/14737140.5.6.1061] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Compounds derived from botanical sources, such as polyphenols from tea, have been of interest as possible therapeutic agents. Their benefits in terms of cancer chemoprevention have also been investigated primarily through in vitro and animal in vivo studies. Ultraviolet light from solar radiation has been proven to initiate and promote skin cancer, which is the most common malignancy in light-skinned populations. This review discusses the effects of tea polyphenols in preventing cutaneous carcinogenesis. Although many of the mechanisms and pathways discussed may be applicable to other carcinogens, this review focuses mainly on those related to ultraviolet light-induced processes and potential action sites for tea polyphenols. Since caffeine is a component of tea, and has also been suggested as a possible chemoprotective agent, it is included in this review. Based on data from numerous studies published in the scientific literature, tea polyphenols are promising chemopreventive agents against ultraviolet-induced skin cancers. Their antioxidant properties, inhibitory effects on signal transduction pathways, cell proliferation, angiogenesis and capacity for apoptosis induction, as well as possible immune protective effects, are among the mechanisms that contribute to skin cancer prevention.
Collapse
Affiliation(s)
- Melissa M Camouse
- Department of Dermatology, University Hospitals and Case Western Reserve University, Lakeside 3500, Cleveland, OH 44106, USA
| | | | | | | |
Collapse
|
36
|
Nakazato T, Ito K, Ikeda Y, Kizaki M. Green tea component, catechin, induces apoptosis of human malignant B cells via production of reactive oxygen species. Clin Cancer Res 2005; 11:6040-9. [PMID: 16115949 DOI: 10.1158/1078-0432.ccr-04-2273] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Green tea polyphenol, (-)-epigallocatechin-3-gallate, has been shown to inhibit cellular proliferation and induce apoptosis of various cancer cells. The aim of this study was to investigate the possibility of (-)-epigallocatechin-3-gallate as a novel therapeutic agent for the patients with B-cell malignancies including multiple myeloma. EXPERIMENTAL DESIGN We investigated the effects of (-)-epigallocatechin-3-gallate on the induction of apoptosis in HS-sultan as well as myeloma cells in vitro and further examined the molecular mechanisms of (-)-epigallocatechin-3-gallate-induced apoptosis. RESULTS (-)-Epigallocatechin-3-gallate rapidly induced apoptotic cell death in various malignant B-cell lines in a dose- and time-dependent manner. (-)-Epigallocatechin-3-gallate-induced apoptosis was in association with the loss of mitochondrial transmembrane potentials (Deltapsim); the release of cytochrome c, Smac/DIABLO, and AIF from mitochondria into the cytosol; and the activation of caspase-3 and caspase-9. Elevation of intracellular reactive oxygen species (ROS) production was also shown during (-)-epigallocatechin-3-gallate-induced apoptosis of HS-sultan and RPMI8226 cells as well as fresh myeloma cells. Antioxidant, catalase, and Mn superoxide dismutase significantly reduced ROS production and (-)-epigallocatechin-3-gallate-induced apoptosis, suggesting that ROS plays a key role in (-)-epigallocatechin-3-gallate-induced apoptosis in B cells. Furthermore, a combination with arsenic trioxide (As2O3) and (-)-epigallocatechin-3-gallate significantly enhanced induction of apoptosis compared with As2O3 alone via decreased intracellular reduced glutathione levels and increased production of ROS. CONCLUSIONS (-)-Epigallocatechin-3-gallate has potential as a novel therapeutic agent for patients with B-cell malignancies including multiple myeloma via induction of apoptosis mediated by modification of the redox system. In addition, (-)-epigallocatechin-3-gallate enhanced As2O3-induced apoptosis in human multiple myeloma cells.
Collapse
Affiliation(s)
- Tomonori Nakazato
- Division of Hematology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | | | | | | |
Collapse
|
37
|
Morito S, Yaguchi K, Imada M, Tachikawa C, Nomura M, Moritani S, Igarashi M, Yokogawa K, Miyamoto KI. Insulin signaling in adipocytes differentiated from mouse stromal MC3T3-G2/PA6 cells. Biol Pharm Bull 2005; 28:2040-5. [PMID: 16272686 DOI: 10.1248/bpb.28.2040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The stromal MC3T3-G2/PA6 (PA6) cells from mouse clavaria did not require insulin for differentiation into mature adipose cells, although insulin is well known to play a key role in adipocyte differentiation. Large lipid droplets were observed in the cytoplasm of PA6 cells, and mRNA expression of the adipose specific proteins (aP2, PPARgamma, C/EBPalpha, FAS, GLUT4, leptin, and adiponectin) as differentiation markers appeared or increased clearly in the cells at 8 d after stimulation without insulin. In addition, the glycerol released from the cells (lipolysis) was increased in a concentration-dependent manner by isoproterenol. However, the isoproterenol-induced lipolysis in the cells was not influenced by treatment with insulin, although that was observed in extramedullary adipocytes, 3T3-L1 cells. On the other hand, the 2-deoxy-D-[1-3H]glucose uptake in differentiated PA6 cells also increased by insulin, as shown in other adipose cells. In the cells, insulin induced the phosphorylation of extracellular signal-regulated kinases (Erks), Akt at Ser 473 and ribosomal p70 S6 protein kinase (p70 S6K) at Thr 389, and the insulin-induced 2-deoxy-D-[1-3H]glucose uptake was inhibited by pre-treatment with wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K), or ML-9, an Akt inhibitor. These results suggest that the insulin signal for adipogenesis (lipogenesis) and lipolysis in bone marrow stroma PA6 cells differs from extramedullary adipocytes, such as 3T3-L1 cells.
Collapse
Affiliation(s)
- Satoshi Morito
- Department of Clinical Pharmacy, Graduate School of Natural Science and Technology, Kanazawa University, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Sen P, Chakraborty PK, Raha S. Tea polyphenol epigallocatechin 3-gallate impedes the anti-apoptotic effects of low-grade repetitive stress through inhibition of Akt and NFκB survival pathways. FEBS Lett 2005; 580:278-84. [PMID: 16376342 DOI: 10.1016/j.febslet.2005.12.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 12/03/2005] [Accepted: 12/05/2005] [Indexed: 01/22/2023]
Abstract
V79 Chinese Hamster lung fibroblasts were subjected to repetitive low-grade stress through multiple exposures to 30 microM H2O2 in culture for 4 weeks. Akt/protein kinase B became phosphorylated at serine473 and threonine308 during this period of repetitive stress. Concurrent exposure of the cells to LY294002 (5 microM), a phosphoinositide-3 kinase inhibitor or 4.5 microM epigallocatechin 3-gallate (EGCG), a tea polyphenol almost completely blocked Akt activation by repetitive stress. Phosphorylation of I kappa B kinase (IKK) and transcriptional activity driven by nuclear factor kappa B (NFkappaB) were significantly enhanced by repetitive oxidative stress. These increases were largely abolished by simultaneous exposure to EGCG. The repetitively stressed cells demonstrated a significant resistance to apoptosis by subsequent acute stress in the form of ultraviolet radiation at 5 J/m2 or H2O2 (7.5 mM). The resistance to apoptosis conferred by repetitive stress was drastically reduced (>80%) by constant exposure to EGCG during the stress period while the presence of LY294002 or the NFkappaB inhibitor SN50 brought about a relatively moderate effect (about 50-65%). Our data indicate that activation of Akt and NFkappaB pro-survival pathways by repetitive low-grade stress results in a strong inhibition of the normal apoptotic response after subsequent acute stress. The tea polyphenol EGCG impedes the activation of both Akt and NFkappaB by repetitive stress and as a result preserves the normal apoptotic response during subsequent acute stress.
Collapse
Affiliation(s)
- Prosenjit Sen
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhan nagar, Kolkata 700064, India
| | | | | |
Collapse
|
39
|
Kobayashi H, Yoshida R, Kanada Y, Fukuda Y, Yagyu T, Inagaki K, Kondo T, Kurita N, Yamada Y, Sado T, Kitanaka T, Suzuki M, Kanayama N, Terao T. A soybean Kunitz trypsin inhibitor reduces tumor necrosis factor-alpha production in ultraviolet-exposed primary human keratinocytes. Exp Dermatol 2005; 14:765-74. [PMID: 16176285 DOI: 10.1111/j.1600-0625.2005.00359.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Cytokines are produced as a consequence of photo-damaged DNA and oxidative stress in ultraviolet (UV)-exposed keratinocytes. A soybean Kunitz trypsin inhibitor (KTI) down-regulates the expression of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) in tumor cells and inflammatory cells. AIM The effect of KTI on TNF-alpha production in UV-exposed primary human keratinocytes was analyzed. RESULTS We show (i) UV induced up-regulation of TNF-alpha mRNA and protein expression in keratinocytes; (ii) cells treated with KTI before UV irradiation showed a significantly lower accumulation of TNF-alpha protein in a dose-dependent manner and a reduced UV-induced up-regulation of TNF-alpha mRNA expression; (iii) KTI inhibited the induction of TNF-alpha target molecules interleukin-1beta (IL-1beta) and IL-6 proteins; (iv) UV irradiation transiently activated c-Jun N-terminal kinase (JNK) and Akt signaling but only weakly activated extracellular signal-regulated kinase (ERK) and p38; (v) KTI specifically inhibited UV-induced activation of ERK, JNK, and p38, but not Akt; (vi) treatment of cells with SP600125, a pharmacological inhibitor of JNK, predominantly suppressed UV-induced up-regulation of TNF-alpha expression; and (vii) KTI did not enhance suppression of UV-induced JNK phosphorylation by SP600125. CONCLUSIONS KTI specifically inhibited UV-induced up-regulation of cytokine expression predominantly through suppression of JNK signaling pathway.
Collapse
Affiliation(s)
- Hiroshi Kobayashi
- Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Handayama, Hamamatsu, Shizuoka, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Ulm R, Nagy F. Signalling and gene regulation in response to ultraviolet light. CURRENT OPINION IN PLANT BIOLOGY 2005; 8:477-82. [PMID: 16039155 DOI: 10.1016/j.pbi.2005.07.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2005] [Accepted: 07/12/2005] [Indexed: 05/03/2023]
Abstract
In contrast to phytochrome-, cryptochrome- and phototropin-sensing systems, about which considerable knowledge has accumulated, the ultraviolet-B (UVB) photoreceptor is not yet known at the molecular level. Information about the downstream signalling events that underlie UVB-provoked physiological responses is limited. Recent whole-genome transcript profiling, isolation of mutants that are impaired in specific UVB-induced responses and detailed photobiological studies suggest that responses that are triggered by shorter wavelength UVB and longer wavelength UVB are mediated by two different sensory systems. The bZIP transcription factor HY5 was recently identified as an important player in the long-wavelength UVB-induced signal transduction cascade. Advances in the development of luciferase-reporter lines will make it feasible to perform high-throughput genetic screens to isolate novel mutants that are impaired in sensing or transducing signals downstream of the putative UVB photoreceptor(s).
Collapse
Affiliation(s)
- Roman Ulm
- Institute of Biology II/Botany, University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.
| | | |
Collapse
|
41
|
Nomura M, Ichimatsu D, Moritani S, Koyama I, Dong Z, Yokogawa K, Miyamoto KI. Inhibition of epidermal growth factor-induced cell transformation and Akt activation by caffeine. Mol Carcinog 2005; 44:67-76. [PMID: 16044420 DOI: 10.1002/mc.20120] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We found that caffeine significantly inhibited epidermal growth factor (EGF)- and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell transformation in the JB6 mouse epidermal cell line. The tumor promoter-induced cell transformation was also blocked by treatment with an adenosine A1 receptor antagonist, 8-phenyltheophylline (8-PTH). Caffeine slightly attenuated activation of EGF-induced activator protein 1 (AP-1) activation, which play important roles in cell transformation, but only at the highest concentration examined (1 mM). Interestingly, pretreatment with caffeine suppressed EGF-induced phosphorylation and activation of Akt and ribosomal p 70 S6 protein kinase (p 70 S 6 K), a target of Akt, without inhibiting phosphatidylinositol 3-kinase (PI 3 K) activation. The inhibition of Akt activation of caffeine was not a result of its adenosine receptor antagonism. Because Akt plays a key role in signal transduction pathways leading to cell proliferation and apoptosis, our results provide novel insight into possible mechanisms of the chemotherapeutic effect of caffeine.
Collapse
Affiliation(s)
- Masaaki Nomura
- Department of Hospital Pharmacy, School of Medicine, Kanazawa University, Kanazawa, Japan
| | | | | | | | | | | | | |
Collapse
|
42
|
Nomura M, Tsukada H, Ichimatsu D, Ito H, Yoshida T, Miyamoto KI. Inhibition of epidermal growth factor-induced cell transformation by tannins. PHYTOCHEMISTRY 2005; 66:2038-46. [PMID: 16153407 DOI: 10.1016/j.phytochem.2005.01.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 01/03/2005] [Indexed: 05/04/2023]
Abstract
The mouse epidermal JB6 cell system is a well developed model for studying tumor promotion, and the JB6 Cl 41 promotion sensitive (P+) cell line, in which transformed colonies are induced by epidermal growth factor (EGF), was used to test the anti-tumor promoting effect of seven tannins and two triterpenoids. We found that six tannins, ellagitannins (compounds 1, 2, 3 and 4) and chromone gallates (compounds 6 and 7), significantly blocked EGF-induced cell transformation in a concentration-dependent manner. The inhibition of cell transformation by the tannins was not due to growth inhibition. The ellagitannins, but not the chromone gallates, significantly attenuated EGF-induced activator protein 1 (AP-1) activation, a transcription factor. Compounds 1 and 3, among the ellagitannins analysed, inhibited the EGF-induced phosphorylation of extracellular-signal regulated protein kinases and p38 kinases, which regulate AP-1 activation. On the other hand, compounds 3 and 4 suppressed EGF-induced phosphatidylinositol 3-kinase (PI3K) activation. In addition, all tannins that blocked cell transformation markedly inhibited EGF-induced activation of Akt, a downstream effector of PI3K. Because signal-transduction pathways, including AP-1 and PI3K pathways, have been focused as prime targets for chemopreventive phytochemicals, our results suggest that inhibition by tannins of EGF-induced neoplastic transformation in JB6 cells is related to blocking of Akt activation, and also attenuation of AP-1 activation for ellagitannins.
Collapse
Affiliation(s)
- Masaaki Nomura
- Department of Hospital Pharmacy, School of Medicine, Kanazawa University, 13-1 Takara-Machi, Kanazawa, Ishikawa 920-8641, Japan
| | | | | | | | | | | |
Collapse
|
43
|
Manson MM. Inhibition of survival signalling by dietary polyphenols and indole-3-carbinol. Eur J Cancer 2005; 41:1842-53. [PMID: 16087329 DOI: 10.1016/j.ejca.2005.05.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Accepted: 05/03/2005] [Indexed: 12/21/2022]
Abstract
Epidemiological studies have long hinted at the possibility that what we eat greatly influences our state of health, in particular our relative risk of developing cancer. In recent years there has been an exponential increase in the number of studies investigating how individual components of the diet interact at the molecular level to determine the fate of a cell. It is now apparent that many such molecules can preferentially inhibit the growth of tumour cells, by inducing cell cycle arrest or apoptosis. The number of signalling pathways and molecular targets involved is continually expanding. Consequently, the picture is becoming ever more complicated, not least because results often appear to be cell-type specific, dose-response relationships are critical, and any one agent appears to have multiple mechanisms of action. In addition most studies have been conducted in cell culture, often with physiologically unachievable concentrations of single agents, making extrapolation to the clinical situation difficult. In this review the mechanisms of action of a few well-studied dietary polyphenols (curcumin, epigallocatechin gallate and resveratrol) and indole-3 carbinol are considered in the light of these issues.
Collapse
Affiliation(s)
- Margaret M Manson
- Cancer Biomarkers and Prevention Group, Department of Biochemistry, Biocentre, University of Leicester, University Road, Leicester LE1 7RH, UK.
| |
Collapse
|
44
|
Traynor NJ, Beattie PE, Ibbotson SH, Moseley H, Ferguson J, Woods JA. Photogenotoxicity of hypericin in HaCaT keratinocytes: Implications for St. John's Wort supplements and high dose UVA-1 therapy. Toxicol Lett 2005; 158:220-4. [PMID: 15890476 DOI: 10.1016/j.toxlet.2005.03.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Revised: 03/31/2005] [Accepted: 03/31/2005] [Indexed: 11/20/2022]
Abstract
Extract of St. John's Wort (Hypericum perforatum) is commonly used as natural remedy for treatment of mild to moderate depression. However, it contains a powerful photoactive component, hypericin, which can cause a severe photodermatitis when eaten by grazing animals (hypericism). In humans, there is evidence that supplementation with St. John's Wort can reduce the minimal erythemal dose (MED) in patients undergoing high dose UVA-1 phototherapy. This is a recent development in phototherapy where the most erythemogenic parts of the UVA spectrum are filtered out, allowing delivery of higher doses of the longer wavelengths of UVA. Although current published evidence suggests that the plasma levels of hypericin are unlikely to cause clinical phototoxicity, it has been established that photoactive compounds can cause DNA damage at sub-toxic and sub-erythemal doses, the effects of which might not be apparent for many years after the event. The present study used HaCaT keratinocytes to investigate the photoclastogenic ability of hypericin on irradiation with UVA. The results show that although the combination of hypericin and UVA light increased the genotoxic burden, when all factors are taken into account, the risk of significant photogenotoxic damage incurred by the combination of Hypericum extracts and UVA phototherapy may be low in the majority of individuals.
Collapse
Affiliation(s)
- N J Traynor
- Photobiology Unit, Department of Dermatology, Ninewells Hospital and Medical School, University of Dundee, Scotland, Dundee DD1 9SY, UK
| | | | | | | | | | | |
Collapse
|
45
|
Shen G, Xu C, Hu R, Jain MR, Nair S, Lin W, Yang CS, Chan JY, Kong ANT. Comparison of (-)-epigallocatechin-3-gallate elicited liver and small intestine gene expression profiles between C57BL/6J mice and C57BL/6J/Nrf2 (-/-) mice. Pharm Res 2005; 22:1805-20. [PMID: 16132347 DOI: 10.1007/s11095-005-7546-8] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2005] [Accepted: 07/18/2005] [Indexed: 12/17/2022]
Abstract
PURPOSE This study was conducted to study global gene expression profiles elicited by (-)-epigallocatechin-3-gallate (EGCG) in mouse liver and small intestine, as well as to identify EGCG-regulated Nrf2-dependent genes. METHODS C57BL/6J and C57BL/6J/Nrf2(-/-) mice were given an oral dose of EGCG at 200 mg/kg or treated with vehicle. Both liver and small intestine were collected 3 h and 12 h after treatment. Total RNA was extracted from the tissues and gene expression profiles were analyzed using Affymetrix mouse genome 430 2.0 array and GeneSpring 6.1 software. Microarray data were validated using quantitative real-time reverse transcription-PCR chain reaction analysis. RESULTS Genes that were either induced or suppressed more than two fold by EGCG treatment compared with vehicle treatment in the same genotype group were filtered using the GeneSpring software. Among these well-defined genes, 671 EGCG-regulated Nrf2-dependent genes and 256 EGCG-regulated Nrf2-independent genes were identified in liver, whereas 228 EGCG-regulated Nrf2-dependent genes and 98 EGCG-regulated Nrf2-independent genes were identified in the small intestine. Based on their biological functions, these genes mainly fall into the category of ubiquitination and proteolysis, electron transport, detoxification, transport, cell growth and apoptosis, cell adhesion, kinase and phosphatases, and transcription factors. CONCLUSIONS Genes expressed in mouse liver are more responsive to oral treatment of EGCG than those expressed in small intestine. EGCG could regulate many genes in both organs in an Nrf2-dependent manner. The identification of genes related to detoxification, transport, cell growth and apoptosis, cell adhesion, kinase, and transcription regulated by EGCG not only provide potential novel insight into the effect of EGCG on global gene expression and chemopreventive effects, but also point to the potential role of Nrf2 in these processes.
Collapse
Affiliation(s)
- Guoxiang Shen
- Graduate Program in Pharmaceutical Science, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Bachelor MA, Cooper SJ, Sikorski ET, Bowden GT. Inhibition of p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase decreases UVB-induced activator protein-1 and cyclooxygenase-2 in a SKH-1 hairless mouse model. Mol Cancer Res 2005; 3:90-9. [PMID: 15755875 DOI: 10.1158/1541-7786.mcr-04-0065] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Activation of activator protein-1 (AP-1) and increased expression of cyclooxygenase-2 (COX-2) have been clearly shown to play a functional role in UVB-induced skin tumor promotion. In this study, we examined UVB-induced signal transduction pathways in SKH-1 mouse epidermis leading to increases in COX-2 expression and AP-1 activity. We observed rapid increases in p38 mitogen-activated protein kinase (MAPK) signaling through activation of p38 MAPK and its downstream target, MAPK activated protein kinase-2. UVB also increased phosphatidylinositol 3-kinase (PI3K) signaling as observed through increases in AKT and GSK-3beta phosphorylation. Activation of the p38 MAPK and PI3K pathways results in the phosphorylation of cyclic AMP-responsive element binding protein, which was also observed in UVB-irradiated SKH-1 mice. Topical treatment with SB202190 (a specific inhibitor of p38 MAPK) or LY294002 (a specific inhibitor of PI3K) significantly decreased UVB-induced AP-1 activation by 84% and 68%, respectively, as well as COX-2 expression. Our data show that in mouse epidermis, UVB activation of the p38 MAPK and PI3K pathways leads to AP-1 activation and COX-2 expression.
Collapse
Affiliation(s)
- Michael A Bachelor
- Department of Cell Biology and Anatomy, Arizona Cancer Center, University of Arizona, 1515 North Campbell Avenue, Room 4999, Tucson, AZ 85724, USA
| | | | | | | |
Collapse
|
47
|
Cabane C, Coldefy AS, Yeow K, Dérijard B. The p38 pathway regulates Akt both at the protein and transcriptional activation levels during myogenesis. Cell Signal 2005; 16:1405-15. [PMID: 15381256 DOI: 10.1016/j.cellsig.2004.05.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 04/27/2004] [Accepted: 05/12/2004] [Indexed: 10/26/2022]
Abstract
The molecular signalling pathways governing skeletal muscle differentiation remain unclear. Recent work has demonstrated that both the phosphatidylinositol 3-kinase (PI3K)/Akt and p38 pathways play important roles in myogenesis. Here, we describe the interactions between these pathways in C2C12 cells. Overall, our results suggest that Akt acts downstream of p38 in myogenic cell differentiation. Activating the p38 pathway results in the concurrent activation of Akt; conversely, activating Akt does not affect p38. We have analysed Akt messenger RNA and protein levels in a C2C12 cell line stably expressing a dominant negative (DN) form of the p38 activator MKK3. Compared to control cells, this cell line exhibits reduced levels of Akt messenger RNA and total protein. In addition, blocking the p38 pathway during differentiation inhibits Akt activation. Our results show for the first time that p38 can directly affect Akt at the transcriptional level as well as at the protein activation level during myogenic differentiation.
Collapse
Affiliation(s)
- Candice Cabane
- UMR CNRS 6548, Laboratoire de Physiologie Cellulaire et Moléculaire, Université de Nice-Sophia Antipolis, Faculté des Sciences, 28 Avenue Valrose, 06108 Nice, France.
| | | | | | | |
Collapse
|
48
|
Akiba T, Yaguchi K, Tsutsumi K, Nishioka T, Koyama I, Nomura M, Yokogawa K, Moritani S, Miyamoto KI. Inhibitory mechanism of caffeine on insulin-stimulated glucose uptake in adipose cells. Biochem Pharmacol 2005; 68:1929-37. [PMID: 15476664 DOI: 10.1016/j.bcp.2004.07.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Accepted: 07/27/2004] [Indexed: 12/26/2022]
Abstract
Caffeine inhibits insulin-induced glucose uptake in rat adipocytes and also decreases insulin sensitivity, including whole-body glucose disposal and glucose uptake in skeletal muscle, during a euglycemic-hyperinsulinemic clamp in human. However, the mechanism by which caffeine decreases the insulin sensitivity is not still clear. We found that pre-treatment with caffeine inhibited the insulin-induced 2-deoxy-D-[1-(3)H]glucose uptake in a concentration-dependent manner in mouse preadipose MC-3T3-G2/PA6 cells differentiated into mature adipose cells. Caffeine also suppressed insulin-induced GLUT4 translocation in the differentiated cells. Although caffeine did not alter insulin-induced activation of PI3K and protein kinase C-zeta (PKCzeta), an isoform of atypical PKC, which is reported to have an important role in insulin-induced GLUT4 translocation, we found that insulin-induced phosphorylation and activation of Akt were blocked by pre-treatment with caffeine. Inhibition of insulin-induced 2-deoxy-D-[1-(3)H]glucose uptake by caffeine was also observed in primary cultured brown adipocytes in a concentration-dependent manner. These results may, in part, explain the ability of caffeine to decrease insulin sensitivity.
Collapse
|
49
|
He Z, Cho YY, Ma WY, Choi HS, Bode AM, Dong Z. Regulation of Ultraviolet B-induced Phosphorylation of Histone H3 at Serine 10 by Fyn Kinase. J Biol Chem 2005; 280:2446-54. [PMID: 15537652 DOI: 10.1074/jbc.m402053200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Ultraviolet B (UVB) induces phosphorylation of histone H3 at serine 10, and mitogen-activated protein kinases are involved in this signal transduction pathway. Here we provide evidence that Fyn kinase, a member of the Src kinase family, is involved in the UVB-induced phosphorylation of histone H3 at serine 10. UVB distinctly increased Fyn kinase activity and phosphorylation. Fyn kinase inhibitors 4-amino-5-(4-chlorophenyl)-7(t-butyl)pyrazol(3,4-d)pyramide and leflunomide, an Src kinase inhibitor, suppressed both UVB-induced phosphorylation of histone H3 at serine 10 and Fyn kinase activity and phosphorylation. UVB-induced phosphorylation of histone H3 at serine 10 was blocked by either a dominant-negative mutant of Fyn (DNM-Fyn) kinase or small interfering RNA of Fyn kinase. UVB-induced phosphorylation and activities of ERKs and protein kinase B/Akt were markedly inhibited by DNM-Fyn kinase. However, DNM-Fyn kinase did not inhibit UVB-induced phosphorylation of p38 MAPK or c-Jun N-terminal kinases. Active Fyn kinase phosphorylated histone H3 at serine 10 in vitro, and the phosphorylated Fyn kinase could translocate into the nucleus of HaCaT cells. These results indicate that Fyn kinase plays a key role in the UVB-induced phosphorylation of histone H3 at serine 10.
Collapse
Affiliation(s)
- Zhiwei He
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
| | | | | | | | | | | |
Collapse
|
50
|
Bode AM, Dong Z. Signal transduction pathways in cancer development and as targets for cancer prevention. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2005; 79:237-97. [PMID: 16096030 DOI: 10.1016/s0079-6603(04)79005-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ann M Bode
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
| | | |
Collapse
|