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Pretorius L, Smith C. Translation of preclinical ethnomedicine data in LMICs: the example of rooibos. Front Pharmacol 2023; 14:1328828. [PMID: 38174224 PMCID: PMC10763253 DOI: 10.3389/fphar.2023.1328828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024] Open
Abstract
All disease, but especially non-communicable diseases, are related to dysfunction of one or more regulatory systems. In developing countries, long-term management of patients with chronic diseases has many challenges and is generally not financially viable, but Africa in particular, which is rich in diverse ethnomedicines presents a more feasible long-term therapeutic approach in this niche. However, despite comprehensive preclinical investigations on numerous plant-derived candidate medicines, only a small portion of these reach the patient as recognised medicines. In this review, we use the example of rooibos (Aspalathus linearis (Burm.f.) R. Dahlgren)-which is globally consumed as aromatic, caffeine-free tea-to illustrate the hurdles that need to be overcome in the low-to middle-income countries, before progression of ethnomedicines to official treatment regimens can be achieved. In terms of methodology, regulatory system focused rooibos papers indexed on PubMed for the past three decades (n = 112) were accessed. Papers reporting duplication of previous results were excluded, as well as review papers. Topics covered includes the high standard of ethnomedicine drug discovery and efficacy testing research performed in Africa (and South Africa in particular in the case of rooibos), the potential bias in terms of preclinical research focus, ethnomedicine ownership and the requirement for independent clinical trial coordination and/or management.
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Affiliation(s)
| | - Carine Smith
- Experimental Medicine, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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Pyrzanowska J. Pharmacological activity of Aspalathus linearis extracts: pre-clinical research in view of prospective neuroprotection. Nutr Neurosci 2023; 26:384-402. [PMID: 35311618 DOI: 10.1080/1028415x.2022.2051955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES Rooibos tea, a very popular everyday beverage made of Aspalathus linearis plant material and containing multiple polyphenolic compounds, reveals an expectation to positively affect various processes observed in the pathogenesis of neurodegenerative diseases as in the case of consumption of other polyphenol-abundant food products. METHODS This review is based on available data from pre-clinical in vitro and in vivo studies and presents a broad report on the pharmacological activity of the A. linearis extracts relevant for neurodegenerative diseases. RESULTS Flavonoids present in herbal infusions are absorbed from gastro-intestinal tract and may affect the central nervous system. The experimental investigations yield the results indicating to supporting role of A. linearis in the prevention of neurodegeneration, primarily owing to anti-oxidative and anti-inflammatory properties, anti-hyperglycaemic and anti-hyperlipidaemic effects as well as favourable impact on neurotransmission with following cognitive and behavioural after-math. DISCUSSION The multiple pharmacological activities and safety of Aspalathus linearis extracts are commented in the manuscript. The continuous rooibos tea consumption seems to be safe (despite anecdotal liver irritation); however, there is a risk of herbal-drug interactions.
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Affiliation(s)
- Justyna Pyrzanowska
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Warsaw, Poland
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Pyrzanowska J. The toxic contaminants of Aspalathus linearis plant material as well as herb-drug interactions may constitute the health risk factors in daily rooibos tea consumers. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2023; 33:129-142. [PMID: 34823434 DOI: 10.1080/09603123.2021.2009780] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Rooibos tea is brewed using Aspalathus linearis plant material sensitive to environmental contamination. This review covers the safety data from preclinical experiments as well as human studies and delivers a report on its hepatic activity. In vitro tea investigation reveals antioxidative and anti-mutagenic features and ability to modulate microsomal enzymes. In rodent research, it exerts protective or neutral impact on liver functions and morphology, yet several human case reports suggest possible acute hepatic damage. Summarizing rooibos consumption seems to be safe in terms of hepatotoxicity; however, there may be designated a group of consumers with higher risk of liver irritation. The contamination of plant material may contribute to herb-induced liver injury. Due to the impact on CYPs, there is a possible risk of herb-drug interactions affecting bioavailability of some co-administered medicines. Caution should be exercised in patients receiving the treatment with allopathic medicines to avoid untoward alteration of drug plasma concentration.
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Affiliation(s)
- Justyna Pyrzanowska
- Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, Centre for Preclinical Research and Technology CePT, Warsaw, Poland
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Wang BJ, Huang SH, Kao CL, Muller CJF, Wang YP, Chang KH, Wen HC, Yeh CC, Shih LJ, Kao YH, Huang SP, Li CY, Chuu CP. Aspalathus linearis suppresses cell survival and proliferation of enzalutamide-resistant prostate cancer cells via inhibition of c-Myc and stability of androgen receptor. PLoS One 2022; 17:e0270803. [PMID: 35776912 PMCID: PMC9249401 DOI: 10.1371/journal.pone.0270803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/06/2022] [Indexed: 11/18/2022] Open
Abstract
Enzalutamide, a nonsteroidal antiandrogen, significantly prolonged the survival of patients with metastatic castration-resistant prostate cancer (CRPC). However, patients receiving enzalutamide frequently develop drug resistance. Rooibos (Aspalathus linearis) is a shrub-like leguminous fynbos plant endemic to the Cedarberg Mountains area in South Africa. We evaluated the possibility of using a pharmaceutical-grade green rooibos extract (GRT, containing 12.78% aspalathin) to suppress the proliferation and survival of enzalutamide-resistant prostate cancer (PCa) cells. Treatment with GRT dose-dependently suppressed the proliferation, survival, and colony formation of enzalutamide-resistant C4-2 MDV3100r cells and PC-3 cells. Non-cancerous human cells were more resistant to GRT treatment. GRT suppressed the expression of proteins involved in phosphoinositide 3-kinase (PI3K)-Akt signaling, androgen receptor (AR), phospho-AR (Ser81), cyclin-dependent kinase 1 (Cdk1), c-Myc and Bcl-2 but increased the expression of apoptotic proteins. Overexpression of c-Myc antagonized the suppressive effects of GRT, while knockdown of c-Myc increased the sensitivity of PCa cells to GRT treatment. Expression level of c-Myc correlated to resistance of PCa cells to GRT treatment. Additionally, immunofluorescence microscopy demonstrated that GRT reduced the abundance of AR proteins both in nucleus and cytoplasm. Treatment with cycloheximide revealed that GRT reduced the stability of AR. GRT suppressed protein expression of AR and AR’s downstream target prostate specific antigen (PSA) in C4-2 MDV3100r cells. Interestingly, we observed that AR proteins accumulate in nucleus and PSA expression is activated in the AR-positive enzalutamide-resistant PCa cells even in the absence of androgen. Our results suggested that GRT treatment suppressed the cell proliferation and survival of enzalutamide-resistant PCa cells via inhibition of c-Myc, induction of apoptosis, as well as the suppression of expression, signaling and stability of AR. GRT is a potential adjuvant therapeutic agent for enzalutamide-resistant PCa.
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Affiliation(s)
- Bi-Juan Wang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
| | - Shih-Han Huang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
- Department of Life Sciences, National Central University, Taoyuan City, Taiwan
| | - Cheng-Li Kao
- Division of Urology, Departments of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
- Division of Urology, Department of Surgery, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan
| | - Christo J. F. Muller
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council, Tygerberg, South Africa
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
| | - Ya-Pei Wang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
| | - Kai-Hsiung Chang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
| | - Hui-Chin Wen
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
| | - Chien-Chih Yeh
- Department of Education and Medical Research, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan
- Division of Colon and Rectal Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Li-Jane Shih
- Department of Education and Medical Research, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan
- Graduate Institute of Medical Science, National Defense Medical Center, Taipei, Taiwan
| | - Yung-Hsi Kao
- Department of Life Sciences, National Central University, Taoyuan City, Taiwan
| | - Shu-Pin Huang
- Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung Taiwan
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Institute of Biomedical Science, National Sun Yat-sen University, Kaohsiung City, Taiwan
| | - Chia-Yang Li
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chih-Pin Chuu
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County, Taiwan
- Department of Life Sciences, National Central University, Taoyuan City, Taiwan
- PhD Program for Aging and Graduate Institute of Basic Medical Science, China Medical University, Taichung City, Taiwan
- Biotechnology Center, National Chung Hsing University, Taichung City, Taiwan
- * E-mail:
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Akindele AJ, Sowemimo A, Agunbiade FO, Sofidiya MO, Awodele O, Ade-Ademilua O, Orabueze I, Ishola IO, Ayolabi CI, Salu OB, Akinleye MO, Oreagba IA. Bioprospecting for Anti-COVID-19 Interventions From African Medicinal Plants: A Review. Nat Prod Commun 2022. [DOI: 10.1177/1934578x221096968] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The emergence of the novel coronavirus (SARS-CoV-2) that emanated from Wuhan in China in 2019 has become a global concern. The current situation warrants ethnomedicinal drug discovery and development for delivery of phytomedicines with potential for the treatment of COVID-19. The aim of this review is to provide a detailed evaluation of available information on plant species used in African traditional medicines with antiviral, anti-inflammatory, immunomodulatory, and COVID-19 symptoms relieving effects. Literature from scientific databases such as Scopus, PubMed, Google scholar, African Journals OnLine (AJOL), Science Direct, and Web of Science were used for this review. A total of 35 of the 38 reviewed plants demonstrated a wide range of antiviral activities. Bryophyllum pinnatum, Aframomum melegueta, Garcinia kola, Sphenocentrum jollyanum, Adansonia digitata, Sutherlandia frutescens, Hibiscus sabdariffa, Moringa oleifera, and Nigella sativa possess a combination of antiviral, immunomodulatory, anti-inflammatory, and COVID-19 symptoms relieving activities. Nine, 13, and 10 of the plants representing 23.7%, 34.2%, and 26.3% of the plants studied had antiviral activity with 3 other activities, antiviral activity with 2 other activities, and antiviral with one pharmacological activity alone, respectively. The plants studied were reported to be relatively safe at the subchronic toxicity level, except for 2. The study provides baseline information on the pharmacological activities, toxicity, and chemical components of 9 African medicinal plants with antiviral, immunomodulatory, anti-inflammatory, and symptoms relieving activities, thereby making the plants candidates for further investigation for effectiveness against COVID-19.
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Affiliation(s)
- Abidemi J. Akindele
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacology, Therapeutics & Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Abimbola Sowemimo
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
| | - Foluso O. Agunbiade
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Chemistry, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Margaret O. Sofidiya
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
| | - Olufunsho Awodele
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacology, Therapeutics & Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Omobolanle Ade-Ademilua
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Botany, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Ifeoma Orabueze
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
| | - Ismail O. Ishola
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacology, Therapeutics & Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Christianah I. Ayolabi
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Microbiology, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Olumuyiwa B. Salu
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Medical Microbiology & Parasitology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
| | - Moshood O. Akinleye
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria
| | - Ibrahim A. Oreagba
- African Center of Excellence for Drug Research, Herbal Medicine Development and Regulatory Science (ACEDHARS), University of Lagos (UNILAG), Lagos, Nigeria
- Department of Pharmacology, Therapeutics & Toxicology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, Lagos, Nigeria
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Takalani NB, Adefolaju GA, Henkel RR, Opuwari CS. In vitro effects of aqueous extract of unfermented rooibos on human spermatozoa. Andrologia 2022; 54:e14452. [PMID: 35545422 PMCID: PMC9541412 DOI: 10.1111/and.14452] [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: 09/22/2021] [Revised: 03/31/2022] [Accepted: 04/18/2022] [Indexed: 11/30/2022] Open
Abstract
The inability to conceive is a baleful experience for thousands of couples worldwide. Among different well‐known reproductive techniques, medicinal plants have been utilized to treat male infertility. Medicinal plants, provide a therapeutic alternative, which is available and affordable for infertile couples. We investigated the direct effect of unfermented rooibos aqueous extract on human spermatozoa. Semen samples (n = 50) collected from donors and patients consulting for fertility were reassigned as normal (n = 22) and abnormal (n = 28) samples based on the outcome of the baseline semen analysis, using the World Health Organization (WHO) cut off value. Semen samples were allowed to liquefy and subsequently washed with human tubular fluid in bovine serum albumin medium. The samples were then treated with aqueous extracts of unfermented rooibos (0, 0.15, 1.5, 15, 150 μg/ml) at 37°C for 1 h and assessed thereafter. Sperm motility, vitality, DNA fragmentation, intracellular reactive oxygen species and mitochondrial membrane potential in both groups remained unchanged (p > 0.05). However, aqueous extract of unfermented rooibos (only at 1.5 μg/ml) significantly increased capacitation and acrosome reaction in the abnormal sample group (p > 0.05). Unfermented rooibos aqueous extract had no deleterious impact on human spermatozoa's function and might be attributed to its antioxidant properties.
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Affiliation(s)
- Ndivhuho Beauty Takalani
- Department of Medical Biosciences, Faculty of Natural Sciences, University of the Western Cape, Cape Town, South Africa.,Department of Pathology and Medical Sciences, Faculty of Health Sciences, University of Limpopo, Sovenga, South Africa
| | | | - Ralf R Henkel
- Department of Medical Biosciences, Faculty of Natural Sciences, University of the Western Cape, Cape Town, South Africa.,American Centre for Reproductive Medicine, Cleveland, Clinic, Cleveland, Ohio, USA.,Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.,LogixX Pharma, Theale, Berkshire, UK
| | - Chinyerum Sylvia Opuwari
- Department of Medical Biosciences, Faculty of Natural Sciences, University of the Western Cape, Cape Town, South Africa
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Gabuza KB, Buthelezi N, Kappo AP, Mabuda TI, Mosa R, Louw J, Muller CJ. In vitro and in vivo hepatotoxicity study of Afriplex™ GRT through an inflammatory response. Toxicol Rep 2022; 9:1920-1928. [DOI: 10.1016/j.toxrep.2022.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 10/04/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
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Takalani NB, Adefolaju GA, Henkel R, Opuwari CS. In vitro effects of aqueous extract of fermented rooibos (Aspalathus linearis) on human sperm function. Andrologia 2021; 53:e14114. [PMID: 33991107 DOI: 10.1111/and.14114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/31/2021] [Accepted: 04/23/2021] [Indexed: 12/17/2022] Open
Abstract
Aspalathus linearis (rooibos) is a herbal medicinal plant originally from South Africa's fynbos and well known for its medicinal effects in treating different medical conditions. Rooibos contains significant levels of antioxidants capable of inhibiting the production of reactive oxygen species, which may improve seminal parameters. This study focussed on investigating the direct effect of fermented rooibos on human sperm functions in vitro. Semen samples collected by masturbation from unproven fertile donors (n = 25) and infertile patients (n = 25) after 3-5 days' abstinence were liquefied and centrifuged (300 × g; 10 min) in human tubular fluid medium containing 1% bovine serum albumin. Afterwards, semen samples (7.5 × 106 /ml) were incubated at 37°C for one hour with aqueous extract of fermented extract in sperm preparation medium (0, 0.10, 1.0, 10 and 100 μg/ml) and assessed. Our data showed that fermented rooibos did not affect functional sperm parameters (motility, vitality, intracellular reactive oxygen species and acrosome reaction, p > .05), in vitro except in the reduced percentage of intact mitochondrial membrane potential and DNA fragmentation (p < .05). The decrease in DNA fragmentation generates the possibility of using the extract in patients prior to assisted reproductive techniques.
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Affiliation(s)
| | | | - Ralf Henkel
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa.,American Centre for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA
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9
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Ponte LGS, Pavan ICB, Mancini MCS, da Silva LGS, Morelli AP, Severino MB, Bezerra RMN, Simabuco FM. The Hallmarks of Flavonoids in Cancer. Molecules 2021; 26:2029. [PMID: 33918290 PMCID: PMC8038160 DOI: 10.3390/molecules26072029] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 12/12/2022] Open
Abstract
Flavonoids represent an important group of bioactive compounds derived from plant-based foods and beverages with known biological activity in cells. From the modulation of inflammation to the inhibition of cell proliferation, flavonoids have been described as important therapeutic adjuvants against several diseases, including diabetes, arteriosclerosis, neurological disorders, and cancer. Cancer is a complex and multifactor disease that has been studied for years however, its prevention is still one of the best known and efficient factors impacting the epidemiology of the disease. In the molecular and cellular context, some of the mechanisms underlying the oncogenesis and the progression of the disease are understood, known as the hallmarks of cancer. In this text, we review important molecular signaling pathways, including inflammation, immunity, redox metabolism, cell growth, autophagy, apoptosis, and cell cycle, and analyze the known mechanisms of action of flavonoids in cancer. The current literature provides enough evidence supporting that flavonoids may be important adjuvants in cancer therapy, highlighting the importance of healthy and balanced diets to prevent the onset and progression of the disease.
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Affiliation(s)
- Luis Gustavo Saboia Ponte
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Isadora Carolina Betim Pavan
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
- Laboratory of Signal Mechanisms (LMS), School of Pharmaceutical Sciences (FCF), University of Campinas (UNICAMP), Campinas, São Paulo 13083-871, Brazil
| | - Mariana Camargo Silva Mancini
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Luiz Guilherme Salvino da Silva
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Ana Paula Morelli
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Matheus Brandemarte Severino
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Rosangela Maria Neves Bezerra
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
| | - Fernando Moreira Simabuco
- Multidisciplinary Laboratory of Food and Health (LabMAS), School of Applied Sciences (FCA), University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (L.G.S.P.); (I.C.B.P.); (M.C.S.M.); (L.G.S.d.S.); (A.P.M.); (M.B.S.); (R.M.N.B.)
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10
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Shabalala SC, Dludla PV, Mabasa L, Kappo AP, Basson AK, Pheiffer C, Johnson R. The effect of adiponectin in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and the potential role of polyphenols in the modulation of adiponectin signaling. Biomed Pharmacother 2020; 131:110785. [PMID: 33152943 DOI: 10.1016/j.biopha.2020.110785] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 02/08/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide, as it affects up to 30 % of adults in Western countries. Moreover, NAFLD is also considered an independent risk factor for cardiovascular diseases. Insulin resistance and inflammation have been identified as key factors in the pathophysiology of NAFLD. Although the mechanisms associated with the development of NAFLD remain to be fully elucidated, a complex interaction between adipokines and cytokines appear to play a crucial role in the development of this condition. Adiponectin is the most common adipokine known to be inversely linked with insulin resistance, lipid accumulation, inflammation and NAFLD. Consequently, the focus has been on the use of new therapies that may enhance hepatic expression of adiponectin downstream targets or increase the serum levels of adiponectin in the treatment NAFLD. While currently used therapies show limited efficacy in this aspect, accumulating evidence suggest that various dietary polyphenols may stimulate adiponectin levels, offering potential protection against the development of insulin resistance, inflammation and NAFLD as well as associated conditions of metabolic syndrome. As such, this review provides a better understanding of the role polyphenols play in modulating adiponectin signaling to protect against NAFLD. A brief discussion on the regulation of adiponectin during disease pathophysiology is also covered to underscore the potential protective effects of polyphenols against NAFLD. Some of the prominent polyphenols described in the manuscript include aspalathin, berberine, catechins, chlorogenic acid, curcumin, genistein, piperine, quercetin, and resveratrol.
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Affiliation(s)
- Samukelisiwe C Shabalala
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council (SAMRC), Tygerberg, 7505, South Africa; Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa, 3886, South Africa
| | - Phiwayinkosi V Dludla
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council (SAMRC), Tygerberg, 7505, South Africa; Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, 60131, Italy
| | - Lawrence Mabasa
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council (SAMRC), Tygerberg, 7505, South Africa
| | - Abidemi P Kappo
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park, 2006, South Africa
| | - Albertus K Basson
- Department of Biochemistry and Microbiology, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa, 3886, South Africa
| | - Carmen Pheiffer
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council (SAMRC), Tygerberg, 7505, South Africa; Department of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, 7505, South Africa
| | - Rabia Johnson
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council (SAMRC), Tygerberg, 7505, South Africa; Department of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, 7505, South Africa.
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Samodien S, Kock MD, Joubert E, Swanevelder S, Gelderblom WCA. Differential Cytotoxicity of Rooibos and Green Tea Extracts against Primary Rat Hepatocytes and Human Liver and Colon Cancer Cells - Causal Role of Major Flavonoids. Nutr Cancer 2020; 73:2050-2064. [PMID: 32930006 DOI: 10.1080/01635581.2020.1820054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Differential anti-proliferative and pro-apoptotic effects of aqueous extracts of green rooibos (Rg; Aspalathus linearis) and green tea (GT; Camellia sinensis) and an aspalathin-enriched extract of green rooibos (GRE), were investigated in primary rat hepatocytes (PH) and human liver (HepG2) and colon (HT-29) cancer cells. Rooibos flavonoids, aspalathin and luteolin, and the green tea flavanol, epigallocatechin gallate (EGCG), were included to assess their contribution relative to their extract concentrations. GRE was the most effective in reducing cell growth parameters which was associated with a high total polyphenol content and high ferric reducing potential. Differential cell responses were noticed with HepG2 cells more sensitive than PH toward the induction of apoptosis by GRE. Luteolin induced apoptosis in PH and HepG2 cells while aspalathin lacked any effect. EGCG induced apoptosis in HepG2 cells while PH were resistant. HT-29 cells were resistant to apoptosis induction by the tea and pure flavonoids. Differences existed in the individual effects of the major rooibos and GT flavonoids against cell growth parameters compared to their equivalent concentrations in the extract mixtures. Diversity of the flavonoid constituents, physicochemical properties and cellular redox status governing cell survival are likely to explain the differential cell responses.
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Affiliation(s)
- Sedicka Samodien
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Bellville, South Africa
| | - Maryna de Kock
- Department of Medical Bioscience Program, University of Western Cape, Bellville, South Africa
| | - Elizabeth Joubert
- Plant Bioactives Group, Agricultural Research Council, Infruitec-Nietvoorbij, Stellenbosch, South Africa.,Department of Food Science, Stellenbosch University, Stellenbosch South Africa
| | - Sonja Swanevelder
- Biostatistics Unit, South African Medical Research Council, Tygerberg, South Africa
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Huang SH, Tseng JC, Lin CY, Kuo YY, Wang BJ, Kao YH, Muller CJF, Joubert E, Chuu CP. Rooibos suppresses proliferation of castration-resistant prostate cancer cells via inhibition of Akt signaling. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 64:153068. [PMID: 31419729 DOI: 10.1016/j.phymed.2019.153068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 07/26/2019] [Accepted: 08/06/2019] [Indexed: 05/22/2023]
Abstract
BACKGROUND Androgen ablation therapy is the primary treatment for metastatic prostate cancer (PCa). However, the majority of PCa patients receiving the androgen deprivation therapy develop recurrent castration-resistant prostate cancer (CRPC) within two years. Chemotherapies show little effect on prolonging survival of CRPC patients and new treatments are needed. Previous studies reported that the extracts from rooibos (Aspalathus linearis) exhibit chemopreventive properties in some cancer models, including skin, liver and oesophagus cancers in animals. We therefore investigate if extracts from rooibos can suppress the proliferation of CRPC cells. PURPOSE We investigated whether an aspalathin-rich green rooibos extract (GRT™; 12.78 g aspalathin/100 g extract) demonstrates anti-cancer activity against CRPC cells. METHODS High performance liquid chromatography (HPLC) was used to profile the major flavonoids in GRT. Hoechst-dye proliferation assay, 3,4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide (MTT) viability assay and flow cytometry assay were used to explore the effects of GRT on the proliferation and cell cycle progression of CRPC cells. Comet assay was used to survey whether GRT induces apoptosis in CRPC cells. LNCaP 104-R1 xenograft nude mice model was used to determine the inhibitory effect of GRT on CRPC tumors in vivo. Micro-Western Array (MWA) and Western blot analysis were carried out to unravel the underlying molecular mechanism. RESULTS GRT contained aspalathin as the most abundant flavonoid. GRT suppressed the proliferation and survival of LNCaP 104-R1, LNCaP FGC and PC-3 PCa cells. Flow cytometry analysis showed that GRT decreased the population of PCa cells in S phase but increased the cell population in G2/M phase. Comet assay confirmed that GRT induced apoptosis in LNCaP 104-R1 cells. Gavage of 400 mg/kg GRT suppressed LNCaP 104-R1 xenografts in castrated nude mice. MWA and Western blot analysis indicated that GRT treatment suppressed Akt1, phospho-Akt Ser473, Cdc2, Bcl-2, TRAF4 and Aven, but increased activated Caspase 3, cytochrome c, and p27Kip1. Overexpression of Akt rescued the suppressive effects of GRT on CRPC cells. Co-treatment of GRT with Bcl-2 inhibitor ABT-737, PI3K inhibitor LY294002 and Akt inhibitor GSK 690693 exhibited additive inhibitory effect on proliferation of CRPC cells. CONCLUSIONS GRT suppresses the proliferation of CRPC cells via inhibition of Akt signaling.
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Affiliation(s)
- Shih-Han Huang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan; Department of Life Sciences, National Central University, Taoyuan City 32001, Taiwan
| | - Jen-Chih Tseng
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan
| | - Ching-Yu Lin
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan
| | - Ying-Yu Kuo
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan; Institute of Biotechnology, National Tsing Hua University, Hsinchu City 30013, Taiwan
| | - Bi-Juan Wang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan
| | - Yung-Hsi Kao
- Department of Life Sciences, National Central University, Taoyuan City 32001, Taiwan
| | - Christo J F Muller
- Biomedical Research and Innovation Platform (BRIP), South African Medical Research Council, Tygerberg 7505, South Africa; Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg 7505, South Africa; Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa
| | - Elizabeth Joubert
- Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch 7599, South Africa; Department of Food Science, Stellenbosch University, Stellenbosch 7599, South Africa
| | - Chih-Pin Chuu
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli County 35053, Taiwan; PhD Program for Aging and Graduate Institute of Basic Medical Science, China Medical University, Taichung City 40402, Taiwan; Biotechnology Center, National Chung Hsing University, Taichung City 40227, Taiwan.
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13
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Mazibuko-Mbeje SE, Dludla PV, Johnson R, Joubert E, Louw J, Ziqubu K, Tiano L, Silvestri S, Orlando P, Opoku AR, Muller CJF. Aspalathin, a natural product with the potential to reverse hepatic insulin resistance by improving energy metabolism and mitochondrial respiration. PLoS One 2019; 14:e0216172. [PMID: 31048842 PMCID: PMC6497260 DOI: 10.1371/journal.pone.0216172] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 04/14/2019] [Indexed: 02/07/2023] Open
Abstract
Aspalathin is a rooibos flavonoid with established blood glucose lowering properties, however, its efficacy to moderate complications associated with hepatic insulin resistance is unknown. To study such effects, C3A liver cells exposed to palmitate were used as a model of hepatic insulin resistance. These hepatocytes displayed impaired substrate metabolism, including reduced glucose transport and free fatty acid uptake. These defects included impaired insulin signaling, evident through reduced phosphatidylinositol-4,5-bisphosphate 3-kinase/ protein kinase B (PI3K/AKT) protein expression, and mitochondrial dysfunction, depicted by a lower mitochondrial respiration rate. Aspalathin was able to ameliorate these defects by correcting altered substrate metabolism, improving insulin signaling and mitochondrial bioenergetics. Activation of 5ʹ-adenosine monophosphate-activated protein kinase (AMPK) may be a plausible mechanism by which aspalathin increases hepatic energy expenditure. Overall, these results encourage further studies assessing the potential use of aspalathin as a nutraceutical to improve hepatocellular energy expenditure, and reverse metabolic disease-associated complications.
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Affiliation(s)
- Sithandiwe E. Mazibuko-Mbeje
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
- * E-mail:
| | - Phiwayinkosi V. Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Rabia Johnson
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Elizabeth Joubert
- Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council, Infruitec-Nietvoorbij, Stellenbosch, South Africa
- Department of Food Science, Stellenbosch University, Stellenbosch, South Africa
| | - Johan Louw
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
| | - Khanyisani Ziqubu
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
| | - Luca Tiano
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Sonia Silvestri
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Patrick Orlando
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Andy R. Opoku
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
| | - Christo J. F. Muller
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
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14
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Fantoukh OI, Dale OR, Parveen A, Hawwal MF, Ali Z, Manda VK, Khan SI, Chittiboyina AG, Viljoen A, Khan IA. Safety Assessment of Phytochemicals Derived from the Globalized South African Rooibos Tea ( Aspalathus linearis) through Interaction with CYP, PXR, and P-gp. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:4967-4975. [PMID: 30955332 DOI: 10.1021/acs.jafc.9b00846] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Rooibos tea ( Aspalathus linearis) is a well-known South African herbal tea enjoyed worldwide. Limited reports indicate the potential of rooibos tea to alter the activity of certain cytochrome P450 (CYP450) isozymes. In this study, the phytochemical investigation of MeOH extract of A. linearis (leaves and stems) resulted in the isolation and characterization of 11 phenolic compounds. The MeOH extract exhibited significant inhibition of the major human CYP450 isozymes (CYP3A4, CYP1A2, CYP2D6, CYP2C9, and CYP2C19). The strongest inhibition was observed by the extract for CYP3A4 (IC50 1.7 ± 0.1 μg/mL) followed by CYP2C19 (IC50 4.0 ± 0.3 μg/mL). Among the tested phytochemicals, the most potent inhibitors were isovitexin on CYP3A4 (IC50 3.4 ± 0.2 μM), vitexin on CYP2C9 (IC50 8.0 ± 0.2 μM), and thermopsoside on CYP2C19 (IC50 9.5 ± 0.2 μM). The two major, structurally related compounds aspalathin and nothofagin exhibited a moderate pregnane-X receptor (PXR) activation, which was associated with increased mRNA expression of CYP3A4 and CYP1A2, respectively. These results indicate that a high intake of nutraceuticals containing rooibos extracts may pose a risk of herb-drug interactions when consumed concomitantly with clinical drugs that are substrates of CYP enzymes.
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Affiliation(s)
- Omer I Fantoukh
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
- Division of Pharmacognosy, Department of BioMolecular Sciences , School of Pharmacy, The University of Mississippi , University , Mississippi 38677 , United States
- Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh 4545 , Saudi Arabia
| | - Olivia R Dale
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
| | - Abidah Parveen
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
- Division of Pharmacognosy, Department of BioMolecular Sciences , School of Pharmacy, The University of Mississippi , University , Mississippi 38677 , United States
| | - Mohammed F Hawwal
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
- Division of Pharmacognosy, Department of BioMolecular Sciences , School of Pharmacy, The University of Mississippi , University , Mississippi 38677 , United States
- Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh 4545 , Saudi Arabia
| | - Zulfiqar Ali
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
| | - Vamshi K Manda
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
| | - Shabana I Khan
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
- Division of Pharmacognosy, Department of BioMolecular Sciences , School of Pharmacy, The University of Mississippi , University , Mississippi 38677 , United States
| | - Amar G Chittiboyina
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
| | - Alvaro Viljoen
- Department of Pharmaceutical Sciences and SAMRC Herbal Drugs Research Unit , Tshwane University of Technology , Pretoria 0183 , South Africa
| | - Ikhlas A Khan
- National Center for Natural Products Research, School of Pharmacy , The University of Mississippi , University , Mississippi 38677 , United States
- Division of Pharmacognosy, Department of BioMolecular Sciences , School of Pharmacy, The University of Mississippi , University , Mississippi 38677 , United States
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Mazibuko-Mbeje SE, Dludla PV, Roux C, Johnson R, Ghoor S, Joubert E, Louw J, Opoku AR, Muller CJF. Aspalathin-Enriched Green Rooibos Extract Reduces Hepatic Insulin Resistance by Modulating PI3K/AKT and AMPK Pathways. Int J Mol Sci 2019; 20:ijms20030633. [PMID: 30717198 PMCID: PMC6387445 DOI: 10.3390/ijms20030633] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 01/26/2019] [Indexed: 12/18/2022] Open
Abstract
We previously demonstrated that an aspalathin-enriched green rooibos extract (GRE) reversed palmitate-induced insulin resistance in C2C12 skeletal muscle and 3T3-L1 fat cells by modulating key effectors of insulin signalling such as phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B (PI3K/AKT) and AMP-activated protein kinase (AMPK). However, the effect of GRE on hepatic insulin resistance is unknown. The effects of GRE on lipid-induced hepatic insulin resistance using palmitate-exposed C3A liver cells and obese insulin resistant (OBIR) rats were explored. GRE attenuated the palmitate-induced impairment of glucose and lipid metabolism in treated C3A cells and improved insulin sensitivity in OBIR rats. Mechanistically, GRE treatment significantly increased PI3K/AKT and AMPK phosphorylation while concurrently enhancing glucose transporter 2 expression. These findings were further supported by marked stimulation of genes involved in glucose metabolism, such as insulin receptor (Insr) and insulin receptor substrate 1 and 2 (Irs1 and Irs2), as well as those involved in lipid metabolism, including Forkhead box protein O1 (FOXO1) and carnitine palmitoyl transferase 1 (CPT1) following GRE treatment. GRE showed a strong potential to ameliorate hepatic insulin resistance by improving insulin sensitivity through the regulation of PI3K/AKT, FOXO1 and AMPK-mediated pathways.
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Affiliation(s)
- Sithandiwe E Mazibuko-Mbeje
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Private Bag X1, Tygerberg 7505, South Africa.
| | - Phiwayinkosi V Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
| | - Candice Roux
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
| | - Rabia Johnson
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Private Bag X1, Tygerberg 7505, South Africa.
| | - Samira Ghoor
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
| | - Elizabeth Joubert
- Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch 7599, South Africa.
- Department of Food Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Johan Louw
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
- Department of Biochemistry and Microbiology, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa.
| | - Andy R Opoku
- Department of Biochemistry and Microbiology, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa.
| | - Christo J F Muller
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
- Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Private Bag X1, Tygerberg 7505, South Africa.
- Department of Biochemistry and Microbiology, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa.
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Correction: Van der Merwe, J.D., et al. Short-Term and Sub-Chronic Dietary Exposure to Aspalathin-Enriched Green Rooibos (Aspalathus linearis) Extract Affects Rat Liver Function and Antioxidant Status. Molecules 2015, 20, 22674-22690. Molecules 2016; 21:molecules21070907. [PMID: 27420037 PMCID: PMC6273007 DOI: 10.3390/molecules21070907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 07/05/2016] [Indexed: 01/08/2023] Open
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