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1.
Environ Toxicol ; 38(10): 2310-2331, 2023 Oct.
Article En | MEDLINE | ID: mdl-37318321

Non-coding microRNAs (miRNAs) have important roles in regulating the expression of liver mRNAs in response to xenobiotic-exposure, but their roles concerning dioxins such as TCDD (2,3,7,8-Tetrachlorodibenzo-p-dioxin) are less clear. This report concerns the potential implication of liver (class I) and circulating (class II) miRNAs in hepatotoxicity of female and male mice after acute exposure to TCDD. The data show that, of a total of 38 types of miRNAs, the expression of eight miRNAs were upregulated in both female and male mice exposed to TCDD. Inversely, the expression of nine miRNAs were significantly downregulated in both animal genders. Moreover, certain miRNAs were preferentially induced in either females or males. The potential downstream regulatory effects of miRNAs on their target genes was evaluated by determining the expression of three group of genes that are potentially involved in cancer biogenesis, other diseases and in hepatotoxicity. It was found that certain cancer-related genes were more highly expressed females rather than males after exposure to TCDD. Furthermore, a paradoxical female-to-male transcriptional pattern was found for several disease-related and hepatotoxicity-related genes. These results suggest the possibility of developing of new miRNA-specific interfering molecules to address their dysfunctions as caused by TCDD.


Chemical and Drug Induced Liver Injury , Dioxins , MicroRNAs , Polychlorinated Dibenzodioxins , Mice , Female , Male , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Dioxins/pharmacology , Polychlorinated Dibenzodioxins/toxicity , Liver
2.
Anim Reprod Sci ; 255: 107277, 2023 Aug.
Article En | MEDLINE | ID: mdl-37315452

Recently, we found that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) - the most toxic dioxin - affected multiple cellular processes in AhR-knocked-down granulosa cells, including the expression of genes and the abundance of proteins. Such alterations may imply the involvement of noncoding RNAs in the remodeling of intracellular regulatory tracks. The aims of the current study were to examine the effects of TCDD on the expression of lncRNAs in AhR-knocked-down granulosa cells of pigs and to indicate potential target genes for differentially expressed lncRNAs (DELs). In the current study, the abundance of AhR protein in porcine granulosa cells was reduced by 98.9% at 24 h after AhR targeted siRNA transfection. Fifty-seven DELs were identified in the AhR-deficient cells treated with TCDD mostly after 3 h (3 h: 56, 12 h: 0, 24 h: 2) after the dioxin treatment. This number was 2.5 times higher than that of intact TCDD-treated granulosa cells. The high number of DELs identified in the early stages of the TCDD action may be associated with a rapid defensive response of cells to harmful actions of this persistent environmental pollutant. In contrast to intact TCDD-treated granulosa cells, AhR-deficient cells were characterized by a broader representation of DELs enriched in GO terms related to the immune response and regulation of transcription and cell cycle. The obtained results support the notion that TCDD may act in an AhR-independent manner. They increase our knowledge on the intracellular mechanism of TCDD action and may in the future contribute to better coping with detrimental consequences of human and animal exposure to TCDD.


Dioxins , Polychlorinated Dibenzodioxins , RNA, Long Noncoding , Humans , Female , Animals , Swine , Polychlorinated Dibenzodioxins/toxicity , Receptors, Aryl Hydrocarbon/genetics , Receptors, Aryl Hydrocarbon/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Dioxins/metabolism , Dioxins/pharmacology , Granulosa Cells , Cell Line
3.
J Endocrinol Invest ; 46(4): 667-677, 2023 Apr.
Article En | MEDLINE | ID: mdl-36526827

PURPOSE: Environmental endocrine-disrupting chemicals (EDCs) are a mixture of chemical compounds capable to interfere with endocrine axis at different levels and to which population is daily exposed. This paper aims to review the relationship between EDCs and breast, prostate, testicle, ovary, and thyroid cancer, discussing carcinogenic activity of known EDCs, while evaluating the impact on public health. METHODS: A literature review regarding EDCs and cancer was carried out with particular interest on meta-analysis and human studies. RESULTS: The definition of EDCs has been changed through years, and currently there are no common criteria to test new chemicals to clarify their possible carcinogenic activity. Moreover, it is difficult to assess the full impact of human exposure to EDCs because adverse effects develop latently and manifest at different ages, even if preclinical and clinical evidence suggest that developing fetus and neonates are most vulnerable to endocrine disruption. CONCLUSION: EDCs represent a major environmental and health issue that has a role in cancer development. There are currently some EDCs that can be considered as carcinogenic, like dioxin and cadmium for breast and thyroid cancer; arsenic, asbestos, and dioxin for prostate cancer; and organochlorines/organohalogens for testicular cancer. New evidence supports the role of other EDCs as possible carcinogenic and pregnant women should avoid risk area and exposure. The relationship between EDCs and cancer supports the need for effective prevention policies increasing public awareness.


Dioxins , Endocrine Disruptors , Testicular Neoplasms , Thyroid Neoplasms , Male , Infant, Newborn , Humans , Female , Pregnancy , Endocrine Disruptors/toxicity , Dioxins/pharmacology , Endocrine System , Thyroid Neoplasms/chemically induced , Thyroid Neoplasms/epidemiology , Carcinogenesis
4.
Bioorg Chem ; 128: 106052, 2022 11.
Article En | MEDLINE | ID: mdl-35921789

Capsid assembly modulators (CAMs) have recently been revealed to be effective in blocking HBV replication. HBV capsid protein inhibitors reduce and ultimately eliminate HBV by inhibiting virus replication and blocking hepatocyte infection. Sulfonamides are synthetic functional groups in development of different kinds of drugs. Sulfonyl benzamide clinical drugs NVR 3-778 and BA-38017 are lead compounds in discovery of antiviral compounds with increased activity and reduced cytotoxicity by drug design strategies including pharmacophore hybrid, bioisosterism and scaffold hopping. In current study, three series of target compounds were synthesized, and their anti-HBV activity was evaluated against HepAD38 cells. Compound 5a (EC50 = 0.50 ± 0.07 µM, CC50 = 48.16 ± 9.15 µM) showed better anti-HBV DNA replication activity than the lead compound BA-38017, and showed good inhibitory effect on the assembly of HBV capsid protein compared with the clinical drug NVR 3-778. In addition, preliminary structure-activity relationship (SAR) and molecular docking studies were conducted to explore potential interactions and binding modes between compounds and target proteins, which may help researchers to find more effective anti-HBV drugs.


Antiviral Agents , Capsid Proteins , Dioxins , Hepatitis B virus , Virus Assembly , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Capsid/metabolism , Dioxins/chemistry , Dioxins/pharmacology , Hepatitis B virus/drug effects , Molecular Docking Simulation , Structure-Activity Relationship
5.
Fish Shellfish Immunol ; 128: 91-100, 2022 Sep.
Article En | MEDLINE | ID: mdl-35921932

The effects of cottonseed protein concentrate (CPC) in place of fishmeal on the growth performance, immune response, digestive ability and intestinal microbiota of Litopenaeus vannamei were investigated in this study. L. vannamei (initial body weight: 0.42 ± 0.01g) was fed for 8 weeks by four isonitrogenous and isolipid feeds with CPC replacing fishmeal (FM) at 0% (control), 15% (CPC15), 30% (CPC30) and 45% (CPC45), respectively. At the end of the study, the final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR) and protein efficiency ratio (PER) of L. vannamei in CPC15 and CPC30 groups were significantly increased, while the feed conversion ratio (FCR) of L. vannamei in the CPC30 group was significantly reduced when compared with the FM group (P < 0.05). After Vibrio parahaemolyticus infection, the cumulative mortality of L. vannamei in CPC15 within 24 hpi was significantly lower than that of the control group (P < 0.05). When compared with the control group, the activities and expression of the immunity-related enzymes in the hepatopancreas had almost the same obvious change trend in the CPC-containing groups, which indicated that the replacement for fishmeal by CPC led to significant immune response in L. vannamei. Besides, significant up-regulation of the digestive enzyme activities were observed in the CPC-containing groups. Analysis of intestinal microbiota showed that significant difference in alpha diversity existed between the CPC-containing groups and the control group. The relative abundances of several top 10 dominated species at the phylum and genus levels were significantly changed in the CPC-containing groups compared with the control group (P < 0.05). Functional prediction of the microbiota indicated that the pathway of protein digestion and absorption was significantly more abundant while the pathways of nitrotoluene degradation, aminobenzoate degradation, atrazine degradation, dioxin degradation and xylene degradation were significantly less abundant in the CPC-containing groups than the FM group (P < 0.05). In summary, optimal dietary CPC replacement of FM could improve the growth, immunity, digestive capacity and the diversities of the intestinal microbial flora of L. vannamei. However, parts of the functions of the intestinal microbial flora were decline.


Atrazine , Dioxins , Gastrointestinal Microbiome , Penaeidae , Aminobenzoates/pharmacology , Animal Feed/analysis , Animals , Body Weight , Cottonseed Oil , Diet/veterinary , Dioxins/pharmacology , Fishes , Immunity , Immunity, Innate , Intestines , Xylenes/analysis , Xylenes/pharmacology
6.
Biosci Biotechnol Biochem ; 86(9): 1207-1210, 2022 Aug 24.
Article En | MEDLINE | ID: mdl-35776953

The structure and inhibitory activity of advanced glycation end products (AGEs) formation were studied using six model compounds and seven phlorotannins isolated from brown alga Ecklonia stolonifera. As a result, it was inferred that AGEs formation inhibitory activity was stronger when electron-rich groups were present because of the addition of many oxygen atoms to the phlorotannins.


Dioxins , Phaeophyceae , Dioxins/chemistry , Dioxins/pharmacology , Glycation End Products, Advanced , Phaeophyceae/chemistry , Structure-Activity Relationship
7.
Sci Rep ; 12(1): 11482, 2022 07 07.
Article En | MEDLINE | ID: mdl-35798792

Epithelial development starts with stem cell commitment to ectoderm followed by differentiation to the basal keratinocytes. The basal keratinocytes, first committed in embryogenesis, constitute the basal layer of the epidermis. They have robust proliferation and differentiation potential and are responsible for epidermal expansion, maintenance and regeneration. We generated basal epithelial cells in vitro through differentiation of mouse embryonic stem cells (mESCs). Early on in differentiation, the expression of stem cell markers, Oct4 and Nanog, decreased sharply along with increased ectoderm marker keratin (Krt) 18. Later on, Krt 18 expression was subdued when cells displayed basal keratinocyte characteristics, including regular polygonal shape, adherent and tight junctions and Krt 14 expression. These cells additionally expressed abundant Sca-1, Krt15 and p63, suggesting epidermal progenitor characteristics. Using Map3k1 mutant mESCs and environmental dioxin, we examined the gene and environment effects on differentiation. Neither Map3k1 mutation nor dioxin altered mESC differentiation to ectoderm and basal keratinocytes, but they, individually and in combination, potentiated Krt 1 expression and basal to spinous differentiation. Similar gene-environment effects were observed in vivo where dioxin exposure increased Krt 1 more substantially in the epithelium of Map3k1+/- than wild type embryos. Thus, the in vitro model of epithelial differentiation can be used to investigate the effects of genetic and environmental factors on epidermal development.


Dioxins , Keratinocytes , MAP Kinase Kinase Kinase 1 , Mouse Embryonic Stem Cells , Animals , Cell Differentiation , Dioxins/pharmacology , Epidermal Cells , Epidermis/metabolism , Keratinocytes/cytology , Keratinocytes/drug effects , MAP Kinase Kinase Kinase 1/genetics , Mice , Mouse Embryonic Stem Cells/cytology , Mutation
8.
Mar Drugs ; 20(2)2022 Feb 04.
Article En | MEDLINE | ID: mdl-35200653

Melanin synthesis is a defense mechanism that prevents skin damage, but excessive accumulation of melanin occurs in the skin in various reactions such as pigmentation, lentigines, and freckles. Although anti-melanogenic effects have been demonstrated for various naturally occurring marine products that inhibit and control tyrosinase activity, most studies have not been extended to in vivo applications. Phlorofucofuroeckol-A (PFF-A, 12.5-100 µM) isolated from Ecklonia cava has previously been shown to have tyrosinase-mitigative effects in B16F10 cells, but it has not been evaluated in an in vivo model, and its underlying mechanism for anti-melanogenic effects has not been studied. In the present study, we evaluated the safety and efficacy of PFF-A for anti-melanogenic effects in an in vivo model. We selected low doses of PFF-A (1.5-15 nM) and investigated their mitigative effects on pigmentation stimulated by α-MSH in vivo and their related-mechanism in an in vitro model. The findings suggest that low-dose PFF-A derived from E. cava suppresses pigmentation in vivo and melanogenesis in vitro. Therefore, this study presents the possibility that PFF-A could be utilized as a new anti-melanogenic agent in the cosmeceutical industries.


Benzofurans/pharmacology , Dioxins/pharmacology , Melanins/biosynthesis , Phaeophyceae/chemistry , Pigmentation/drug effects , Animals , Benzofurans/administration & dosage , Benzofurans/isolation & purification , Cell Line, Tumor , Dioxins/administration & dosage , Dioxins/isolation & purification , Dose-Response Relationship, Drug , Female , Male , Melanoma, Experimental/metabolism , Mice , Zebrafish , alpha-MSH/metabolism
9.
Drug Chem Toxicol ; 45(6): 2463-2470, 2022 Nov.
Article En | MEDLINE | ID: mdl-34308744

The present study aimed to investigate the protective role of capsaicin in a rat model of 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD)-induced toxicity. Exposure to TCDD which is an environmental toxicant causes severe toxic effects in the animal and human tissues. Therefore, the potential protective effect of capsaicin in TCDD-induced organ damage was investigated in rats by measuring thiobarbituric acid reactive substances (TBARS) level, superoxide dismutase (SOD) activity, and glutathione (GSH) level in the heart, liver, and kidney tissues for oxidant/antioxidant balance. Thirty-two healthy adults (250-300 g weight and 3-4 months old) male Wistar albino rats were randomly distributed into four equal groups (n = 8): Control, CAP, TCDD, TCDD + CAP. A dose of 2 µg/kg TCDD or a dose of 25 mg/kg capsaicin were dissolved in corn oil and orally administered to the rats for 30 days. The results indicated that TCDD-induced oxidative stress by increasing the level of TBARS and by decreasing the levels of GSH, and SOD activity in the tissues of rats. However, capsaicin treatment was significantly decreased TBARS levels and was significantly increased GSH level and SOD activity (p < 0.05). In addition, capsaicin (25 mg/kg) significantly attenuated TCDD-induced histopathological alteration associated with oxidative stress in the heart, liver, and kidney tissues (p < 0.05). As capsaicin regulates oxidative imbalance and attenuates histopathological alterations in the rat tissues, it may be preventing agents in TCDD toxicity.


Dioxins , Polychlorinated Dibenzodioxins , Animals , Male , Rats , Antioxidants/pharmacology , Capsaicin/pharmacology , Corn Oil/pharmacology , Dioxins/pharmacology , Glutathione/metabolism , Oxidants , Oxidative Stress , Polychlorinated Dibenzodioxins/toxicity , Rats, Wistar , Superoxide Dismutase/metabolism , Thiobarbituric Acid Reactive Substances
10.
Sovrem Tekhnologii Med ; 13(2): 84-94, 2021.
Article En | MEDLINE | ID: mdl-34513081

At present, diseases of bones and joints stand third after cardiovascular and oncological pathologies which demands the necessity of searching for new etiological factors and pathogenetical mechanisms of these illnesses. The accumulating data show the association between the impairment of bone tissue development and regeneration and endocrine disruptor impact. Endocrine disruptors are chemical substances, mainly of anthropogenic origin, capable of affecting endocrine system functioning and interfering with organ morphogenesis and physiological functions. The development and regeneration of bone tissues have a complex hormonal regulation and therefore bone tissue cells, osteoblasts, and osteoclasts can be considered as potential targets for endocrine disruptors. Endocrine disruptors have been established to be able to impair calcium metabolism which also contributes to the development of musculoskeletal system pathology. Data on histogenesis of bone tissue and regeneration, calcium metabolism as well as on hormonal regulation of bone growth and remodeling processes are presented in this work. Recent information on the effect of the main endocrine disruptor classes (diethylstilbestrol, organochlorine pesticides, alkylphenols, bisphenol A, dioxins, polychlorinated biphenyls, and phthalic acid esters) on the development and remodeling of bone tissues and calcium metabolism has been summarized. The established physiological and molecular mechanisms of their action have been also considered.


Dioxins , Endocrine Disruptors , Bone and Bones , Dioxins/pharmacology , Endocrine Disruptors/adverse effects , Osteoblasts , Osteoclasts
11.
Mar Drugs ; 19(8)2021 Aug 01.
Article En | MEDLINE | ID: mdl-34436282

One of the well-known causes of hearing loss is noise. Approximately 31.1% of Americans between the ages of 20 and 69 years (61.1 million people) have high-frequency hearing loss associated with noise exposure. In addition, recurrent noise exposure can accelerate age-related hearing loss. Phlorofucofuroeckol A (PFF-A) and dieckol, polyphenols extracted from the brown alga Ecklonia cava, are potent antioxidant agents. In this study, we investigated the effect of PFF-A and dieckol on the consequences of noise exposure in mice. In 1,1-diphenyl-2-picrylhydrazyl assay, dieckol and PFF-A both showed significant radical-scavenging activity. The mice were exposed to 115 dB SPL of noise one single time for 2 h. Auditory brainstem response(ABR) threshold shifts 4 h after 4 kHz noise exposure in mice that received dieckol were significantly lower than those in the saline with noise group. The high-PFF-A group showed a lower threshold shift at click and 16 kHz 1 day after noise exposure than the control group. The high-PFF-A group also showed higher hair cell survival than in the control at 3 days after exposure in the apical turn. These results suggest that noise-induced hair cell damage in cochlear and the ABR threshold shift can be alleviated by dieckol and PFF-A in the mouse. Derivatives of these compounds may be applied to individuals who are inevitably exposed to noise, contributing to the prevention of noise-induced hearing loss with a low probability of adverse effects.


Antioxidants/therapeutic use , Benzofurans/therapeutic use , Dioxins/therapeutic use , Hearing Loss, Noise-Induced/drug therapy , Kelp , Plant Extracts/therapeutic use , Animals , Antioxidants/pharmacology , Aquatic Organisms , Benzofurans/pharmacology , Cochlea/drug effects , Dioxins/pharmacology , Disease Models, Animal , Evoked Potentials, Auditory, Brain Stem/drug effects , Hair Cells, Auditory/drug effects , Male , Mice , Mice, Inbred C57BL , Phytotherapy , Plant Extracts/pharmacology
12.
Mar Drugs ; 19(3)2021 Mar 17.
Article En | MEDLINE | ID: mdl-33802989

The liver is vulnerable to oxidative stress-induced damage, which leads to many diseases, including alcoholic liver disease (ALD). Liver disease endanger people's health, and the incidence of ALD is increasing; therefore, prevention is very important. 7-phloro-eckol (7PE) is a seaweed polyphenol, which was isolated from Ecklonia cava in a previous study. In this study, the antioxidative stress effect of 7PE on HepG2/CYP2E1 cells was evaluated by alcohol-induced cytotoxicity, DNA damage, and expression of related inflammation and apoptosis proteins. The results showed that 7PE caused alcohol-induced cytotoxicity to abate, reduced the amount of reactive oxygen species (ROS) and nitric oxide (NO), and effectively inhibited DNA damage in HepG2/CYP2E1 cells. Additionally, the expression levels of glutathione (GSH), superoxide dismutase (SOD), B cell lymphoma 2 (Bcl-2), and Akt increased, while γ-glutamyltransferase (GGT), Bcl-2 related x (Bax), cleaved caspase-3, cleaved caspase-9, nuclear factor-κB (NF-κB), and JNK decreased. Finally, molecular docking proved that 7PE could bind to BCL-2 and GSH protein. These results indicate that 7PE can alleviate the alcohol-induced oxidative stress injury of HepG2 cells and that 7PE may have a potential application prospect in the future development of antioxidants.


Antioxidants/pharmacology , Cytochrome P-450 CYP2E1/metabolism , Dioxins/pharmacology , Hepatocytes/drug effects , Oxidative Stress/drug effects , Phaeophyceae/metabolism , Seaweed/metabolism , Antioxidants/isolation & purification , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Dioxins/isolation & purification , Ethanol/toxicity , Hep G2 Cells , Hepatocytes/enzymology , Humans , Inflammation Mediators/metabolism , Molecular Structure , Reactive Oxygen Species/metabolism , Signal Transduction
13.
Int J Mol Sci ; 22(8)2021 Apr 19.
Article En | MEDLINE | ID: mdl-33921823

Hypertension induces renal fibrosis or tubular interstitial fibrosis, which eventually results in end-stage renal disease. Epithelial-to-mesenchymal transition (EMT) is one of the underlying mechanisms of renal fibrosis. Though previous studies showed that Ecklonia cava extracts (ECE) and dieckol (DK) had inhibitory action on angiotensin (Ang) I-converting enzyme, which converts Ang I to Ang II. It is known that Ang II is involved in renal fibrosis; however, it was not evaluated whether ECE or DK attenuated hypertensive nephropathy by decreasing EMT. In this study, the effect of ECE and DK on decreasing Ang II and its down signal pathway of angiotensin type 1 receptor (AT1R)/TGFß/SMAD, which is related with the EMT and restoring renal function in spontaneously hypertensive rats (SHRs), was investigated. Either ECE or DK significantly decreased the serum level of Ang II in the SHRs. Moreover, the renal expression of AT1R/TGFß/SMAD was decreased by the administration of either ECE or DK. The mesenchymal cell markers in the kidney of SHRs was significantly decreased by ECE or DK. The fibrotic tissue of the kidney of SHRs was also significantly decreased by ECE or DK. The ratio of urine albumin/creatinine of SHRs was significantly decreased by ECE or DK. Overall, the results of this study indicate that ECE and DK decreased the serum levels of Ang II and expression of AT1R/TGFß/SMAD, and then decreased the EMT and renal fibrosis in SHRs. Furthermore, the decrease in EMT and renal fibrosis could lead to the restoration of renal function. It seems that ECE or DK could be beneficial for decreasing hypertensive nephropathy by decreasing EMT and renal fibrosis.


Benzofurans/therapeutic use , Angiotensin II/metabolism , Animals , Benzofurans/pharmacology , Blood Pressure/drug effects , Dioxins/pharmacology , Epithelial-Mesenchymal Transition/drug effects , Fibrosis/drug therapy , Fibrosis/metabolism , Hypertension, Renal/drug therapy , Hypertension, Renal/metabolism , Kidney/drug effects , Kidney/metabolism , Male , Nephritis/drug therapy , Nephritis/metabolism , Rats , Signal Transduction/drug effects
14.
Front Immunol ; 12: 630427, 2021.
Article En | MEDLINE | ID: mdl-33659010

Cigarette smoke is a prevalent respiratory toxicant that remains a leading cause of death worldwide. Cigarette smoke induces inflammation in the lungs and airways that contributes to the development of diseases such as lung cancer and chronic obstructive pulmonary disease (COPD). Due to the presence of aryl hydrocarbon receptor (AhR) ligands in cigarette smoke, activation of the AhR has been implicated in driving this inflammatory response. However, we have previously shown that the AhR suppresses cigarette smoke-induced pulmonary inflammation, but the mechanism by which the AhR achieves its anti-inflammatory function is unknown. In this study, we use the AhR antagonist CH-223191 to inhibit AhR activity in mice. After an acute (3-day) cigarette smoke exposure, AhR inhibition was associated with significantly enhanced neutrophilia in the airways in response to cigarette smoke, mimicking the phenotype of AhR-deficient mice. We then used genetically-modified mouse strains which express an AhR that can bind ligand but either cannot translocate to the nucleus or bind its cognate response element, to show that these features of the AhR pathway are not required for the AhR to suppress pulmonary neutrophilia. Finally, using the non-toxic endogenous AhR ligand FICZ, we provide proof-of-concept that activation of pulmonary AhR attenuates smoke-induced inflammation. Collectively, these results support the importance of AhR activity in mediating its anti-inflammatory function in response to cigarette smoke. Further investigation of the precise mechanisms by which the AhR exerts is protective functions may lead to the development of therapeutic agents to treat people with chronic lung diseases that have an inflammatory etiology, but for which few therapeutic options exist.


Basic Helix-Loop-Helix Transcription Factors/physiology , Dioxins/pharmacology , Neutrophils/pathology , Nicotiana/adverse effects , Pulmonary Disease, Chronic Obstructive/prevention & control , Receptors, Aryl Hydrocarbon/physiology , Response Elements/physiology , Smoke/adverse effects , Acute Disease , Animals , Azo Compounds/pharmacology , Carbazoles/pharmacology , Female , Male , Mice , Pyrazoles/pharmacology
15.
Endocrinology ; 162(6)2021 06 01.
Article En | MEDLINE | ID: mdl-33693622

CONTEXT: Human studies consistently show an association between exposure to persistent organic pollutants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, aka "dioxin"), and increased diabetes risk. We previously showed that a single high-dose TCDD exposure (20 µg/kg) decreased plasma insulin levels in male and female mice in vivo, but effects on glucose homeostasis were sex-dependent. OBJECTIVE: The current study assessed whether prolonged exposure to a physiologically relevant low-dose of TCDD impacts glucose homeostasis and/or the islet phenotype in a sex-dependent manner in chow-fed or high-fat diet (HFD)-fed mice. METHODS: Male and female mice were exposed to 20 ng/kg/d TCDD 2×/week for 12 weeks and simultaneously fed standard chow or a 45% HFD. Glucose homeostasis was assessed by glucose and insulin tolerance tests, and glucose-induced plasma insulin levels were measured in vivo. Histological analysis was performed on pancreas from male and female mice, and islets were isolated from females for TempO-Seq transcriptomic analysis. RESULTS: Low-dose TCDD exposure did not lead to adverse metabolic consequences in chow-fed male or female mice, or in HFD-fed males. However, TCDD accelerated the onset of HFD-induced hyperglycemia and impaired glucose-induced plasma insulin levels in females. TCDD caused a modest increase in islet area in males but reduced the percent beta cell area within islets in females. TempO-Seq analysis suggested abnormal changes to endocrine and metabolic pathways in female TCDDHFD islets. CONCLUSION: Our data suggest that prolonged low-dose TCDD exposure has minimal effects on glucose homeostasis and islet morphology in chow-fed male and female mice but promotes maladaptive metabolic responses in HFD-fed females.


Adaptation, Physiological/drug effects , Diet, High-Fat/adverse effects , Dioxins/pharmacology , Animals , Blood Glucose/drug effects , Blood Glucose/metabolism , Chronic Disease , Dose-Response Relationship, Drug , Energy Metabolism/drug effects , Environmental Exposure/adverse effects , Environmental Pollutants/pharmacology , Female , Insulin/metabolism , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/metabolism , Male , Mice , Mice, Inbred C57BL , Polychlorinated Dibenzodioxins/pharmacology , Sex Characteristics , Time Factors
16.
Mol Metab ; 42: 101104, 2020 12.
Article En | MEDLINE | ID: mdl-33075544

OBJECTIVE: Exposure to persistent organic pollutants is consistently associated with increased diabetes risk in humans. We investigated the short- and long-term impact of transient low-dose dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) exposure during pregnancy and lactation on glucose homeostasis and beta cell function in female mice, including their response to a metabolic stressor later in life. METHODS: Female mice were injected with either corn oil (CO; vehicle control) or 20 ng/kg/d TCDD 2x/week throughout mating, pregnancy and lactation, and then tracked for 6-10 weeks after chemical exposure stopped. A subset of CO- and TCDD-exposed dams was then transferred to a 45% high-fat diet (HFD) or remained on a standard chow diet for an additional 11 weeks to assess the long-term effects of TCDD on adaptability to a metabolic stressor. To summarize, female mice were transiently exposed to TCDD and then subsequently tracked beyond when TCDD had been excreted to identify lasting metabolic effects of TCDD exposure. RESULTS: TCDD-exposed dams were hypoglycemic at birth but otherwise had normal glucose homeostasis during and post-TCDD exposure. However, TCDD-exposed dams on a chow diet were modestly heavier than controls starting 5 weeks after the last TCDD injection, and their weight gain accelerated after transitioning to a HFD. TCDD-exposed dams also had an accelerated onset of hyperglycemia, impaired glucose-induced plasma insulin levels, reduced islet size, increased MAFA-ve beta cells, and increased proinsulin accumulation following HFD feeding compared to controls. Overall, our study demonstrates that low-dose TCDD exposure during pregnancy has minimal effects on metabolism during the period of active exposure, but has detrimental long-term effects on metabolic adaptability to HFD feeding. CONCLUSIONS: Our study suggests that transient low-dose TCDD exposure in female mice impairs metabolic adaptability to HFD feeding, demonstrating that dioxin exposure may be a contributing factor to obesity and diabetes pathogenesis in females.


Dioxins/adverse effects , Obesity/metabolism , Animals , Diabetes Mellitus , Diet, High-Fat , Dioxins/metabolism , Dioxins/pharmacology , Disease Susceptibility/chemically induced , Female , Glucose/metabolism , Insulin/metabolism , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/physiology , Lactation/drug effects , Lactation/metabolism , Liver/metabolism , Mice , Mice, Inbred C57BL , Pregnancy
17.
J Reprod Immunol ; 142: 103192, 2020 11.
Article En | MEDLINE | ID: mdl-32950783

BACKGROUND: Neisseria gonorrhoeae (N.g) is Gram-negative bacteria and can lead to endometritis in female. Toll-like receptors regulate immune response in various diseases. However, the roles of TLR2 and TLR4 in. Neisseria gonorrhoeae-induced infection damage in human endometrial epithelia were investigated. METHODS: hEECs were infected with N.g (MOI 10 and 100) and cell viability and apoptosis were measured by CCK8 and flow cytometry assays in both infected groups with the uninfected normal hEECs as negative control. TLR2/TLR4 proteins were measured by ELISA method. Pro-inflammatory markers NLRP3, PGES (PGE2) and TNF-α were assessed by RT-qPCR (mRNA expression) and Elisa (protein concentrations). Transfection assays were performed to up- or down- regulate expression of TLR2 and TLR4 so as to study the functions of TLR2/TLR4 in. N.g-infected hEECs, followed by apoptosis and inflammation assessment. Similarly, we explored the interactions between TLR2/TLR4 and Nrf2/NF-κB/p65 by knocking down TLR2/TLR4 to detect the signaling and further regulating the signaling to evaluate TLR2/ TLR4, apoptosis and inflammation in cells. RESULTS: N.g suppressed cell viabilities and induced cell apoptosis and inflammation. TLR2/TLR4 downregulation inhibited the infection damage. Nrf2 was activated while NF-κB/p65 was depleted as TLR2/ TLR4 was knocked down. Activation of Nrf2 and inhibition of NF-κB resulted in decrease of TLR2/TLR4, which could retard apoptosis and inflammation induced by N.g infection. CONCLUSION: TLR2/TLR4 depletion could alleviate the N.g-infected hEECs via Nrf2/NF-kB signaling, suggesting that TLR2/TLR4 inhibitors might serve as a treatment to reduce N.g infection in human endometrial epithelia.


Endometritis/immunology , Gonorrhea/immunology , Neisseria gonorrhoeae/immunology , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Apoptosis/drug effects , Apoptosis/genetics , Apoptosis/immunology , Benzamides/pharmacology , Cell Survival/drug effects , Cell Survival/genetics , Cell Survival/immunology , Cells, Cultured , Dihydropyridines/pharmacology , Dioxins/pharmacology , Down-Regulation , Endometritis/drug therapy , Endometritis/microbiology , Endometritis/pathology , Endometrium/cytology , Endometrium/immunology , Endometrium/metabolism , Endometrium/pathology , Epithelial Cells/immunology , Epithelial Cells/metabolism , Epithelial Cells/pathology , Female , Gene Knockdown Techniques , Gonorrhea/drug therapy , Gonorrhea/microbiology , Gonorrhea/pathology , Humans , NF-E2-Related Factor 2/agonists , NF-E2-Related Factor 2/metabolism , Primary Cell Culture , Signal Transduction/drug effects , Signal Transduction/immunology , Toll-Like Receptor 2/antagonists & inhibitors , Toll-Like Receptor 2/genetics , Toll-Like Receptor 4/antagonists & inhibitors , Toll-Like Receptor 4/genetics , Transcription Factor RelA/antagonists & inhibitors , Transcription Factor RelA/metabolism
18.
Mar Drugs ; 18(9)2020 Sep 17.
Article En | MEDLINE | ID: mdl-32957728

Diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae (IO) showed potential whitening effects against UV-B radiation. However, the components of IO as well as their molecular mechanism against α-melanocyte-stimulating hormone (α-MSH) have not yet been investigated. Thus, this study aimed to investigate the inhibitory effects of Ishophloroglucin A (IPA), a phlorotannin isolated from brown algae IO, and its crude extract (IOE), in melanogenesis in vivo in an α-MSH-induced zebrafish model and in B16F10 melanoma cells in vitro. Molecular docking studies of the phlorotannins were carried out to determine their inhibitory effects and to elucidate their mode of interaction with tyrosinase, a glycoprotein related to melanogenesis. In addition, morphological changes and melanin content decreased in the α-MSH-induced zebrafish model after IPA and IOE treatment. Furthermore, Western blotting results revealed that IPA upregulated the extracellular related protein expression in α-MSH-stimulated B16F10 cells. Hence, these results suggest that IPA isolated from IOE has a potential for use in the pharmaceutical and cosmetic industries.


Benzofurans/pharmacology , Dioxins/pharmacology , Melanins/biosynthesis , Melanocytes/drug effects , Phaeophyceae/metabolism , Skin Lightening Preparations/pharmacology , alpha-MSH/pharmacology , Animals , Benzofurans/isolation & purification , Dioxins/isolation & purification , JNK Mitogen-Activated Protein Kinases/metabolism , Melanocytes/metabolism , Melanocytes/pathology , Melanoma, Experimental/metabolism , Melanoma, Experimental/pathology , Mice , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Phosphorylation , Skin Lightening Preparations/isolation & purification , Zebrafish , p38 Mitogen-Activated Protein Kinases/metabolism
19.
Bioorg Chem ; 102: 104075, 2020 09.
Article En | MEDLINE | ID: mdl-32777641

Poly(ADP-ribose) polymerase 1 (PARP1), a widely explored anticancer drug target, plays an important role in single-strand DNA break repair processes. High-throughput virtual screening (HTVS) of a Maybridge small molecule library using the PARP1-benzimidazole-4-carboxamide co-crystal structure and pharmacophore model led to the identification of eleven compounds. These compounds were evaluated using recombinant PARP1 enzyme assay that resulted in the acquisition of three PARP1 inhibitors: 3 (IC50 = 12 µM), 4 (IC50 = 5.8 µM), and 10 (IC50 = 0.88 µM). Compound 4 (2,3-dihydro-1,4-benzodioxine-5-carboxamide) was selected as a lead and was subjected to further chemical modifications, involving analogue synthesis and scaffold hopping. These efforts led to the identification of (Z)-2-(4-hydroxybenzylidene)-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazine-8-carboxamide (49, IC50 = 0.082 µM) as the most potent inhibitor of PARP1 from the series.


Dioxins/chemical synthesis , Dioxins/therapeutic use , High-Throughput Screening Assays/methods , Poly(ADP-ribose) Polymerase Inhibitors/chemical synthesis , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Dioxins/pharmacology , Humans , Molecular Docking Simulation , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Structure-Activity Relationship
20.
Food Funct ; 11(7): 6509-6516, 2020 Jul 22.
Article En | MEDLINE | ID: mdl-32633748

Brown seaweed (Phaeophyceae) polyphenolics such as phlorotannins are ascribed various biological activities, including neuroprotection. Of these seaweeds, Ecklonia radiata (E. radiata) is found abundantly along South Australian coastal regions; however it has not been explored for various biological activities relative to any component phlorotannins previously ascribed neuroprotective capacity. In the present study, we evaluated neuroprotective activity against the neurotoxic amyloid ß protein (Aß1-42) of an ethanol extract of E. radiata compared with various additional solvent-solubilised fractions in a neuronal PC-12 cell line. The ethyl acetate fraction comprising 62% phlorotannins demonstrated the most efficacious neuroprotective activity, inhibiting neurotoxicity at all Aß1-42 concentrations. In addition, this fraction demonstrated a significant reduction in Aß aggregate density, but did not alter overall aggregate morphology. Centrifugal partitioning chromatography was used to isolate the major component, eckol, in high yield and liquid chromatography-mass spectrometry was used to characterize the major components of the ethyl acetate fraction. Our results demonstrate that the prevalence of eckol-type phlorotannins are associated with neuroprotective bioactivity of E. radiata, suggestive of potential nutraceutical and biopharmaceutical uses of this brown seaweed phlorotannin in dementia.


Amyloid beta-Peptides/metabolism , Dioxins/pharmacology , Neurons/drug effects , Peptide Fragments/metabolism , Phaeophyceae/chemistry , Plant Extracts/pharmacology , Amyloid beta-Peptides/toxicity , Animals , Australia , Biological Products/chemistry , Cell Survival/drug effects , Humans , Neuroprotective Agents/pharmacology , Neurotoxicity Syndromes/drug therapy , PC12 Cells , Peptide Fragments/toxicity , Plant Extracts/chemistry , Rats , Seaweed/chemistry , Tannins/pharmacology
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