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Arabacı Tamer S, Eskiler GG, Ercan F. Gastroprotective effect of vanillic acid against ethanol-induced gastric injury in rats: involvement of the NF-κB signalling and anti-apoptosis role. Mol Biol Rep 2024; 51:744. [PMID: 38874632 DOI: 10.1007/s11033-024-09672-6] [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: 04/05/2024] [Accepted: 05/23/2024] [Indexed: 06/15/2024]
Abstract
BACKGROUND Vanillic acid (VA; 4-hydroxy-3-methoxybenzoic acid) is a flavouring agent found in various natural sources such as olives, fruits, and green tea. While VA exhibits numerous pharmacological effects, its potential protective effects against gastric injury warrants further investigation. Therefore, the primary objective of this study is to elucidate investigate the gastroprotective properties of VA against ethanol-induced gastric injury. METHODS AND RESULTS Rats were orally administered either saline or VA at different doses (50, 100, and 200 mg/kg/day), with omeprazole (20 mg/kg) serving as a positive control, for fourteen consecutive days before ethanol administration. Blood and gastric tissue samples were collected one hour after ethanol administration for biochemical, molecular, and histological analyses. Pre-treatment with VA before ulcer induction alleviated both macroscopic and microscopic damage. It also increased antioxidant glutathione levels and decreased malondialdehyde and myeloperoxidase activity, along with reducing inflammatory markers such as tumour necrosis factor (TNF)-α, interleukin (IL)-6, and nuclear factor kappa B (NF-κB). Additionally, VA pre-treatment reversed the elevation of Bax mRNA expression and gastric caspase-3 levels induced by gastric damage. It also mitigated the reduction in Bcl-2 mRNA expression. CONCLUSION These findings suggest that VA exerts protective effects against ethanol-induced gastric injury in rats. It achieves this by augmenting gastric antioxidant capacity and mitigating oxidative, inflammatory, and apoptotic damage.
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Affiliation(s)
- Sevil Arabacı Tamer
- School of Medicine, Department of Physiology, Sakarya University, Korucuk Mah. Konuralp Bulvarı No: 81/1 Korucuk Kampüsü, Adapazarı Sakarya, 54100, Türkiye.
| | - Gamze Güney Eskiler
- School of Medicine, Department of Medical Biology, Sakarya University, Sakarya, Türkiye
| | - Feriha Ercan
- School of Medicine, Department of Histology and Embryology, Marmara University, İstanbul, Türkiye
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Liu C, Wang W, Zhao S, Chen S, Chen H, Wang S, Li Z, Qian H, Tian X. Discovery of first-in-class highly selective TRPV1 antagonists with dual analgesic and hypoglycemic effects. Bioorg Med Chem 2024; 107:117750. [PMID: 38776567 DOI: 10.1016/j.bmc.2024.117750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/04/2024] [Accepted: 05/06/2024] [Indexed: 05/25/2024]
Abstract
Analgesia and blood sugar control are considered as two main unmet clinical needs for diabetes related neuropathic pain patients. Transient receptor potential vanilloid type-1 (TRPV1) channel is a highly validated target for pain perception, while no TRPV1 antagonists have been approved due to hyperthermia side effects. Herein, two series of new TRPV1 antagonists with flavonoid skeleton were designed by the structure-based drug design (SBDD) strategy. After comprehensive evaluation, compound CX-3 was identified as a promising TRPV1 antagonist. CX-3 exhibited equivalent TRPV1 antagonistic activity with classical TRPV1 antagonist BCTC in vitro, and exerted better analgesic activity in vivo than that of BCTC in the formalin induced inflammatory pain model without hyperthermia risk. Moreover, CX-3 exhibited robust glucose-lowering effects and showed high selectivity over other ion channels. Overall, these findings identified a first-in-class highly selective TRPV1 antagonist CX-3, which is a promising candidate to target the pathogenesis of diabetes related neuropathic pain.
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Affiliation(s)
- Chunxia Liu
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China; Henan Key Laboratory of Precision Clinical Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China
| | - Wenxin Wang
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China
| | - Shiyu Zhao
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China; Henan Key Laboratory of Precision Clinical Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China
| | - Siliang Chen
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China
| | - Haoyang Chen
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China; Henan Key Laboratory of Precision Clinical Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China
| | - Suhua Wang
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China; Henan Key Laboratory of Precision Clinical Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China
| | - Zheng Li
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, PR China.
| | - Hai Qian
- Center of Drug Discovery, State Key Laboratory of Natural Medicines, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, PR China.
| | - Xin Tian
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China; Henan Key Laboratory of Precision Clinical Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, PR China.
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3
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Lin K, Fu D, Wang Z, Zhang X, Zhu C. Analgesic and anti-inflammatory effects of galangin: a potential pathway to inhibit transient receptor potential vanilloid 1 receptor activation. Korean J Pain 2024; 37:151-163. [PMID: 38557656 PMCID: PMC10985483 DOI: 10.3344/kjp.23363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/26/2024] [Accepted: 03/18/2024] [Indexed: 04/04/2024] Open
Abstract
Background Galangin, commonly employed in traditional Chinese medicine for its diverse medicinal properties, exhibits potential in treating inflammatory pain. Nevertheless, its mechanism of action remains unclear. Methods Mice were randomly divided into 4 groups for 7 days: a normal control group, a galangin-treated (25 and 50 mg/kg), and a positive control celecoxib (20 mg/kg). Analgesic and anti-inflammatory effects were evaluated using a hot plate test, acetic acid-induced writhing test, acetic acid-induced vascular permeability test, formalininduced paw licking test, and carrageenan-induced paw swelling test. The interplay between galangin, transient receptor potential vanilloid 1 (TRPV1), NF-κB, COX-2, and TNF-α proteins was evaluated via molecular docking. COX- 2, PGE2, IL-1β, IL-6, and TNF-α levels in serum were measured using ELISA after capsaicin administration (200 nmol/L). TRPV1 expression in the dorsal root ganglion was analyzed by Western blot. The quantities of substance P (SP) and calcitonin gene-related peptide (CGRP) were assessed using qPCR. Results Galangin reduced hot plate-induced licking latency, acetic acid-induced contortions, carrageenantriggered foot inflammation, and capillary permeability in mice. It exhibited favorable affinity towards TRPV1, NF- κB, COX-2, and TNF-α, resulting in decreased levels of COX-2, PGE2, IL-1β, IL-6, and TNF-α in serum following capsaicin stimulation. Galangin effectively suppressed the upregulation of TRPV1 protein and associated receptor neuropeptides CGRP and SP mRNA, while concurrently inhibiting the expression of NF-κB, TNF-α, COX-2, and PGE2 mRNA. Conclusions Galangin exerts its anti-inflammatory pain effects by inhibiting TRPV1 activation and regulating COX-2, NF-κB/TNF-α expression, providing evidence for the use of galangin in the management of inflammatory pain.
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Affiliation(s)
- Kaiwen Lin
- Hainan Women and Children’s Medical Center, Haikou, China
| | - Datian Fu
- Hainan Women and Children’s Medical Center, Haikou, China
| | - Zhongtao Wang
- Hainan Women and Children’s Medical Center, Haikou, China
| | - Xueer Zhang
- Hainan Women and Children’s Medical Center, Haikou, China
| | - Canyang Zhu
- Hainan Women and Children’s Medical Center, Haikou, China
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Hao B, Yang Z, Liu H, Liu Y, Wang S. Advances in Flavonoid Research: Sources, Biological Activities, and Developmental Prospectives. Curr Issues Mol Biol 2024; 46:2884-2925. [PMID: 38666911 PMCID: PMC11049524 DOI: 10.3390/cimb46040181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 04/28/2024] Open
Abstract
At present, the occurrence of a large number of infectious and non-communicable diseases poses a serious threat to human health as well as to drug development for the treatment of these diseases. One of the most significant challenges is finding new drug candidates that are therapeutically effective and have few or no side effects. In this respect, the active compounds in medicinal plants, especially flavonoids, are potentially useful compounds with a wide range of pharmacological activities. They are naturally present in nature and valuable in the treatment of many infectious and non-communicable diseases. Flavonoids are divided into fourteen categories and are mainly derived from plant extraction, chemical synthesis and structural modification, and biosynthesis. The structural modification of flavonoids is an important way to discover new drugs, but biosynthesis is currently considered the most promising research direction with the potential to revolutionize the new production pipeline in the synthesis of flavonoids. However, relevant problems such as metabolic pathway analyses and cell synthesis protocols for flavonoids need to be addressed on an urgent basis. In the present review, new research techniques for assessing the biological activities of flavonoids and the mechanisms of their biological activities are elucidated and their modes of interaction with other drugs are described. Moreover, novel drug delivery systems, such as nanoparticles, bioparticles, colloidals, etc., are gradually becoming new means of addressing the issues of poor hydrophilicity, lipophilicity, poor chemical stability, and low bioavailability of flavonoids. The present review summarizes the latest research progress on flavonoids, existing problems with their therapeutic efficacy, and how these issues can be solved with the research on flavonoids.
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Affiliation(s)
| | | | | | | | - Shengyi Wang
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou 730050, China; (B.H.); (Z.Y.); (H.L.); (Y.L.)
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Zagórska J, Pietrzak K, Kukula-Koch W, Czop M, Wojtysiak K, Koch W. Influence of Thermal Treatment on the Composition of Alpinia officinarum Rhizome. Int J Mol Sci 2024; 25:3625. [PMID: 38612437 PMCID: PMC11012154 DOI: 10.3390/ijms25073625] [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: 02/25/2024] [Revised: 03/20/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024] Open
Abstract
Alpinia officinarum is a representative of the Zingiberaceae family, which is known for its wide use in the food and pharmaceutical industries also due to its precious pharmacological potential. The major aim of the present study was to evaluate the influence of thermal treatment on the composition of the rhizome of Alpinia officinarum and its antioxidant activity. The fresh rhizome was subjected to various thermal treatment processes-boiling, frying and microwave heating during various time intervals-and their composition and antioxidant activity were determined using chromatographic (HPLC - High Performance Liquid Chromatography and HPLC-MS - High Performance Liquid Chromatography Mass Spectrometry) and spectrophotometric (DPPH and TPC - Total Phenolic Content) methods. Pinobanksin was the main compound found in the extract of the fresh rhizome (537.79 mg/kg), followed by galangin (197.7 mg/kg) and zingerone (185.5 mg/kg). The effect of thermal treatment on the rhizome composition was varied. In general, thermal processing significantly decreased the content of active compounds in the rhizome. However, there were some exceptions-boiling for 4 min significantly increased the content of pinobanksin (1162.4 mg/kg) and galangin (280.7 mg/kg), and microwave processing for 4 min increased the content of pinocembrin (213 mg/kg). It was found that boiling and microwave treatment significantly increased the antioxidant activity of the processed rhizomes.
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Affiliation(s)
- Justyna Zagórska
- Department of Food and Nutrition, Medical University of Lublin, 4a Chodzki Str., 20-093 Lublin, Poland; (J.Z.); (K.P.); (K.W.)
| | - Karolina Pietrzak
- Department of Food and Nutrition, Medical University of Lublin, 4a Chodzki Str., 20-093 Lublin, Poland; (J.Z.); (K.P.); (K.W.)
| | - Wirginia Kukula-Koch
- Department of Pharmacognosy with Medical Plants Garden, Medical University of Lublin, 1 Chodzki Str., 20-093 Lublin, Poland;
| | - Marcin Czop
- Department of Clinical Genetics, Medical University of Lublin, 11 Radziwiłłowska Str., 20-080 Lublin, Poland;
| | - Karolina Wojtysiak
- Department of Food and Nutrition, Medical University of Lublin, 4a Chodzki Str., 20-093 Lublin, Poland; (J.Z.); (K.P.); (K.W.)
| | - Wojciech Koch
- Department of Food and Nutrition, Medical University of Lublin, 4a Chodzki Str., 20-093 Lublin, Poland; (J.Z.); (K.P.); (K.W.)
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Xu DD, Hou ZQ, Xu YY, Liang J, Gao YJ, Zhang C, Guo F, Huang DD, Ge JF, Xia QR. Potential Role of Bmal1 in Lipopolysaccharide-Induced Depression-Like Behavior and its Associated "Inflammatory Storm". J Neuroimmune Pharmacol 2024; 19:4. [PMID: 38305948 DOI: 10.1007/s11481-024-10103-3] [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: 07/11/2022] [Accepted: 01/02/2024] [Indexed: 02/03/2024]
Abstract
Inflammation plays an important role in the pathogenesis of depression; however, the underlying mechanisms remain unclear. Apart from the disordered circadian rhythm in animal models and patients with depression, dysfunction of clock genes has been reported to be involved with the progress of inflammation. This study aimed to investigate the role of circadian clock genes, especially brain and muscle ARNT-like 1 (Bmal1), in the linkage between inflammation and depression. Lipopolysaccharide (LPS)-challenged rats and BV2 cells were used in the present study. Four intraperitoneal LPS injections of 0.5 mg/kg were administered once every other day to the rats, and BV2 cells were challenged with LPS for 24 h at the working concentration of 1 mg/L, with or without the suppression of Bmal1 via small interfering RNA. The results showed that LPS could successfully induce depression-like behaviors and an "inflammatory storm" in rats, as indicated by the increased immobility time in the forced swimming test and the decreased saccharin preference index in the saccharin preference test, together with hyperactivity of the hypothalamic-pituitary-adrenal axis, hyperactivation of astrocyte and microglia, and increased peripheral and central abundance of tumor necrosis factor-α, interleukin 6, and C-reactive protein. Moreover, the protein expression levels of brain-derived neurotrophic factor, triggering receptor expressed on myeloid cells 1, Copine6, and Synaptotagmin1 (Syt-1) decreased in the hippocampus and hypothalamus, whereas the expression of triggering receptor expressed on myeloid cells 2 increased. Interestingly, the fluctuation of temperature and serum concentration of melatonin and corticosterone was significantly different between the groups. Furthermore, protein expression levels of the circadian locomotor output cycles kaput, cryptochrome 2, and period 2 was significantly reduced in the hippocampus of LPS-challenged rats, whereas Bmal1 expression was significantly increased in the hippocampus but decreased in the hypothalamus, where it was co-located with neurons, microglia, and astrocytes. Consistently, apart from the reduced cell viability and increased phagocytic ability, LPS-challenged BV2 cells presented a similar trend with the changed protein expression in the hippocampus of the LPS model rats. However, the pathological changes in BV2 cells induced by LPS were reversed after the suppression of Bmal1. These results indicated that LPS could induce depression-like pathological changes, and the underlying mechanism might be partly associated with the imbalanced expression of Bmal1 and its regulated dysfunction of the circadian rhythm.
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Affiliation(s)
- Dan-Dan Xu
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China
- Anhui Provincial Laboratory of Inflammatory and Immunity Disease, Anhui Institute of Innovative Drugs, Hefei, China
| | - Zhi-Qi Hou
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China
- Anhui Provincial Laboratory of Inflammatory and Immunity Disease, Anhui Institute of Innovative Drugs, Hefei, China
| | - Ya-Yun Xu
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China
- School of Public Health, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, People's Republic of China
| | - Jun Liang
- Department of Pharmacy, Hefei Fourth People's Hospital, Anhui Mental Health Center, 316 Huangshan Road, Hefei, 230032, China
- Clinical Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, China
- Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, China
| | - Ye-Jun Gao
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- Department of Pharmacy, Hefei Fourth People's Hospital, Anhui Mental Health Center, 316 Huangshan Road, Hefei, 230032, China
- Clinical Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, China
- Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, China
| | - Chen Zhang
- School of 1, Clinic Medicine, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, People's Republic of China
| | - Fan Guo
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China
- Anhui Provincial Laboratory of Inflammatory and Immunity Disease, Anhui Institute of Innovative Drugs, Hefei, China
| | - Dan-Dan Huang
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China
- Anhui Provincial Laboratory of Inflammatory and Immunity Disease, Anhui Institute of Innovative Drugs, Hefei, China
| | - Jin-Fang Ge
- School of Pharmacy, Anhui Medical University, 81 Mei-Shan Road, Hefei, 230032, Anhui, People's Republic of China.
- The Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Medical University, Hefei, China.
- Anhui Provincial Laboratory of Inflammatory and Immunity Disease, Anhui Institute of Innovative Drugs, Hefei, China.
| | - Qing-Rong Xia
- Department of Pharmacy, Hefei Fourth People's Hospital, Anhui Mental Health Center, 316 Huangshan Road, Hefei, 230032, China.
- Clinical Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, China.
- Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, China.
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Takata T, Motoo Y. Novel In Vitro Assay of the Effects of Kampo Medicines against Intra/Extracellular Advanced Glycation End-Products in Oral, Esophageal, and Gastric Epithelial Cells. Metabolites 2023; 13:878. [PMID: 37512585 PMCID: PMC10385496 DOI: 10.3390/metabo13070878] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 07/30/2023] Open
Abstract
Kampo medicines are Japanese traditional medicines developed from Chinese traditional medicines. The action mechanisms of the numerous known compounds have been studied for approximately 100 years; however, many remain unclear. While components are normally affected through digestion, absorption, and metabolism, in vitro oral, esophageal, and gastric epithelial cell models avoid these influences and, thus, represent superior assay systems for Kampo medicines. We focused on two areas of the strong performance of this assay system: intracellular and extracellular advanced glycation end-products (AGEs). AGEs are generated from glucose, fructose, and their metabolites, and promote lifestyle-related diseases such as diabetes and cancer. While current technology cannot analyze whole intracellular AGEs in cells in some organs, some AGEs can be generated for 1-2 days, and the turnover time of oral and gastric epithelial cells is 7-14 days. Therefore, we hypothesized that we could detect these rapidly generated intracellular AGEs in such cells. Extracellular AEGs (e.g., dietary or in the saliva) bind to the receptor for AGEs (RAGE) and the toll-like receptor 4 (TLR4) on the surface of the epithelial cells and can induce cytotoxicity such as inflammation. The analysis of Kampo medicine effects against intra/extracellular AGEs in vitro is a novel model.
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Affiliation(s)
- Takanobu Takata
- Division of Molecular and Genetic Biology, Department of Life Science, Medical Research Institute, Kanazawa Medical University, Uchinada 920-0293, Ishikawa, Japan
| | - Yoshiharu Motoo
- Department of Medical Oncology and Kampo Medicines, Komatsu Sophia Hospital, Komatsu 923-0861, Ishikawa, Japan
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Miličević A. Estimating flavonoid oxidation potentials: mechanisms and charge-related regression models. Arh Hig Rada Toksikol 2023; 74:99-105. [PMID: 37357878 PMCID: PMC10291500 DOI: 10.2478/aiht-2023-74-3721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/01/2023] [Accepted: 05/01/2023] [Indexed: 06/27/2023] Open
Abstract
In this paper, I tested our quadratic regression models for the estimation of flavonoid oxidation potentials based on spin populations, the differences in the net atomic charges between a cation and a neutral flavonoid, between a radical and an anion of a flavonoid, and between a radical and a neutral flavonoid on a larger set of flavonoids (N = 35). By including six new flavonoids (5,6,7-trihydroxyflavone, 3,3',4',7-tetrahydroxyflavone, 3,7-dihydroxyflavone, 4',7-dihydroxyflavone, 4',5,7-trihydroxyisoflavone, and 6-hydroxyflavone), we created a respectable calibration set of 35 flavonoids with their oxidation potentials all measured at the same conditions by the same experimentalist. The best model was based on the mean values of the three variables using differences in the net atomic charges (R 2 = 0.970, S.E. = 0.043), which are connected with the three different mechanisms of electrochemical oxidation, SET-PT, SPLET, and HAT.
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Affiliation(s)
- Ante Miličević
- Institute for Medical Research and Occupational Health, Zagreb, Croatia
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