Poncirin Impact on Human HER2 Breast Cancer Cells: Inhibiting Proliferation, Metastasis, and Tumor Growth in Mice Potentially through The PI3K/AKT Pathway.

OBJECTIVE: Breast cancer is a prevalent and heterogeneous disease, with human epidermal growth factor receptor-2 (HER2) overexpression occurring in over 20% of cases. Poncirin, a biologically active flavonone derived from the immature dried fruits of Poncirus trifoliata, is a 7-O-neohesperidoside of isosakuranetin with a well-documented history in traditional Chinese medicine for its health-promoting properties. While the previous research hinted at its potential as an anticancer agent, its specific effects on HER2 overexpressing breast cancer cells remain largely unexplored. The aim of this study is to investigate the specific effects of Poncirin, on HER2 overexpressing breast cancer cells. MATERIALS AND METHODS: In experimental study, we assessed cell proliferation using the CCK-8 assay and explored cell migration and invasion with transwell assays. Additionally, we evaluated colony formation ability and examined apoptosis through the acridine orange/ethidium bromide (AO/EB) and Annexin V-fluorescein isothiocyanate (FITC)/ propidium iodide (PI) staining methods. The study also delved into the molecular mechanisms involved by scrutinizing the phosphatidylinositol 3-kinase/serine-threonine protein kinase (PI3K/AKT) signaling pathway via Western blotting. Furthermore, the researchers conducted in vivo experiments using mouse models to corroborate the findings in a living organism. RESULTS: Poncirin demonstrated a remarkable ability to selectively inhibit proliferation and metastasis of HER2 overexpressing breast cancer cells. Mechanistically, the compound seemed to exert its effects by modulating the PI3K/AKT signaling pathway, implying its central role in the observed anticancer effects. These findings were further substantiated by in vivo experiments, which consistently showed a reduction in tumor growth when poncirin was administered. CONCLUSION: This study underscores potential of poncirin as a potent agent for restraining the growth and metastasis of HER2 overexpressing breast cancer cells. The evidence suggests that poncirin efficacy may be attributed to its modulation possibly through PI3K/AKT pathway.

Alleviating depressive-like behavior in DSS-induced colitis mice: Exploring naringin and poncirin from Poncirus trifoliata extracts.

Patients with inflammatory bowel diseases (IBDs), including ulcerative colitis (UC) and Crohn's disease (CD), often have concomitant mental disorders such as depression and anxiety. Therefore, a bidirectional approach involving the gut and brain axes is necessary for the prevention and treatment thereof. In this study, we explored the potential of Poncirus trifoliata extract (PT), traditionally known for its neuroprotective effects against gastrointestinal diseases, as a natural treatment agent for IBD in a dextran sulfate sodium (DSS)-induced colitis model. Oral administration of PT ameliorated weight loss and inflammatory responses in mice with DSS-induced colitis. Furthermore, PT treatment effectively restored the colon length and ameliorated enterocyte death by inhibiting DSS-induced reactive oxygen species (ROS)-mediated necroptosis. The main bioactive components of PT, poncirin and naringin, confirmed using ultra-performance liquid chromatography-quadrupole time-of-flight (UPLC-qTOF), can be utilized to regulate necroptosis. The antidepressant-like effects of PT were confirmed using open field test (OFT) and tail suspension test (TST). PT treatment also restored vascular endothelial cell integrity in the hippocampus. In the Cornu Ammonis 1 (CA1) and dentate gyrus (DG) regions of the hippocampus, PT controlled the neuroinflammatory responses of proliferated microglia. In conclusion, PT, which contains high levels of poncirin and naringin, has potential as a bidirectional therapeutic agent that can simultaneously improve IBD-associated intestinal and mental disorders.

Computational approaches to define poncirin from Magnolia champaka leaves as a novel multi-target inhibitor of SARS-CoV-2.

Phytochemical-based drug discovery against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been the focus of the current scenario. In this context, we aimed to perform the phytochemical profiling of Magnolia champaka, an evergreen tree from the Magnoliaceae family, in order to perform a virtual screening of its phytoconstituents against different biological targets of SARS-CoV-2. The phytochemicals identified from the ethanol extract of M. champaka leaves using liquid chromatography-mass spectroscopy (LC-MS) technique were screened against SARS-CoV-2 spike glycoprotein (PDB ID: 6M0J), main protease/Mpro (PDB ID: 6LU7), and papain-like protease/PLpro (PDB ID: 7CMD) through computational tools. The experimentation design included molecular docking simulation, molecular dynamics simulation, and binding free energy calculations. Through molecular docking simulation, we identified poncirin as a common potential inhibitor of all the above-mentioned target proteins. In addition, molecular dynamics simulations, binding free energy calculations, and PCA analysis also supported the outcomes of the virtual screening. By the virtue of all the in silico results obtained, poncirin could be taken for in vitro and in vivo studies in near future.Communicated by Ramaswamy H. Sarma.

Effects of Poncirin, a Citrus Flavonoid and Its Aglycone, Isosakuranetin, on the Gut Microbial Diversity and Metabolomics in Mice.

Poncirin (PC) and its aglycone, isosakuranetin (IR), occur naturally in citrus fruits. This study aimed to explore the pathways behind the different health benefits of PC and IR by evaluating the effect of these two bioactive flavonoids on the gut microbial diversity and metabolomics of mice. The 16S rRNA gene sequencing was used to analyze the alteration of gut microbiota in mice after PC and IR intervention. The metabolic impact of PC and IR in mice were studied using a metabolomics approach based on LC-MS analysis. Results showed that, after 7 days intervention, PC and IR multiplied the abundance of Parabacteroides in mice's intestinal tracts by 1.2 and 1.0 times, respectively. PC increased the abundance of Bacteroides by 2.4 times. IR reduced the Allobaculum abundance by 1.0 time and increased Alloprevotella abundance by 1.5 times. When mice were given PC, their fecal acetic acid level increased by 1.8 times, while their isobutyric and isovaleric acid content increased by 1.2 and 1.3 times, respectively. Supplementation with IR had no significant effect on the content of short-chain fatty acids (SCFAs) in the feces of mice. The potential urine biomarkers of mice in the PC group were involved in the digestion and absorption of protein and carbohydrate, as well as the metabolism of amino acids, such as glycine, serine, threonine, tryptophan, D-arginine, D-ornithine, etc. IR mainly affected the amino acid metabolic pathways in mice, including taurine and hypotaurine metabolism, glutathione metabolism, histidine metabolism, D-glutamate metabolism, etc. This study provided valuable clues for future research on the health promoting mechanisms of PC and IR.

Anti-Obesity Potential of Ponciri Fructus: Effects of Extracts, Fractions and Compounds on Adipogenesis in 3T3-L1 Preadipocytes.

BACKGROUND: Ponciri Fructus, a crude drug consisting of the dried immature fruits of Poncirus trifoliata (L.) Raf., is a popular folk medicine used for the treatment of allergy and gastrointestinal disorders in Korea and China. In this study, the anti-adipogenic activity of extracts and isolated compounds were evaluated using 3T3-L1 preadipocytes. METHODS: Dried immature fruits were extracted and fractionated into n-hexane, ethyl acetate (EtOAc), n-butanol and water-soluble fractions. The ethanol extract and fractions were tested for anti-adipogenic activity in the 3T3-L1 cell line. The active fractions (n-hexane and EtOAc fractions) were further subjected to chromatographic techniques to isolate and identify active compounds. Furthermore, the isolated compounds were evaluated for their anti-adipogenic activity. RESULTS: Altogether, seven compounds, including two flavonoids, one phytosteroid and four coumarin derivatives, were isolated. Ethanol extract, n-hexane fraction, EtOAc fraction and three isolated compounds (phellopterin, oxypeucedanin and poncirin) showed significant anti-adipogenic activity as observed by reduced lipid deposition in differentiated 3T3-L1 cells. Further, oxypeucedanin downregulated the key adipogenic markers, such as peroxisome proliferator-activated receptors proteins γ (PPAR-γ), sterol response element binding proteins-1 (SREBP-1), CCAAT/enhancer binding proteins-α (C/EBP-α), adipocyte-specific lipid binding proteins (FABP-4), adipocyte fatty acid binding proteins (aP2), lipoprotein lipase (LPL) and leptin. CONCLUSION: This study indicated that the ethanol extract, hexane fraction and ethyl acetate fraction of P. trifoliata fruits possess strong anti-adipogenic activity, containing the active compounds such as phellopterin, oxypeucedanin and poncirin. Further research is recommended to explore their efficacy and safety in animal and clinical models.

Poncirin ameliorates cardiac ischemia-reperfusion injury by activating PI3K/AKT/PGC-1α signaling.

Poncirin, a flavonoid glycoside derivative extracted from the fruits of Poncirus trifoliata (trifoliate orange or Chinese bitter orange), has a variety of documented bioactivities, including anti-tumor, anti-inflammatory, and antioxidant effects. Oxidative stress is a major underlying factor in the pathogenesis of cardiac ischemia-reperfusion (I/R) injury. Therefore, we investigated the protective efficacy of poncirin on primary cardiomyocytes subjected to anoxia-reoxygenation (A/R) injury in vitro, and on rat hearts subjected to ischemia-reperfusion (I/R) injury in vivo. Poncirin pretreatment enhanced cardiomyocyte survival, inhibited A/R-induced oxidative stress by upregulating cellular antioxidant capacity, suppressed mitochondrial depolarization, and ultimately inhibited apoptosis. Similarly, systemic poncirin treatment significantly reduced cardiomyocyte apoptosis and infarct size in rat hearts. In addition, activity of the PI3K/AKT/PGC-1α pathway was significantly increased by poncirin pretreatment in both A/R and I/R injury models, while PI3K and PGC-1α inhibitors abolished all poncirin related effects, suggesting that this pathway is essential for the cardioprotective effects of poncirin. Pretreatment with the PGC-1α inhibitor reversed effects of poncirin without affecting p-AKT expression, indicating that PGC-1α is downstream of AKT. In conclusion, both in vitro and in vivo studies suggested that poncirin alleviates cardiac ischemia-reperfusion injury by mitigating oxidative stress, which is dependent on activation of the PI3K/AKT/PGC-1α signaling pathway.

Comprehensive in vivo and in silico approaches to explore the hepatoprotective activity of poncirin against paracetamol toxicity.

In the present study, poncirin was evaluated against paracetamol-induced liver injury using in vivo and computational approaches. Paracetamol was administered intraperitoneally (i.p,) to establish liver injury in mice and, subsequently, to investigate the hepatoprotective effect of poncirin (administered intraperitoneally) on liver injury. The effect of poncirin was evaluated against the liver injury markers and inflammatory cytokines. Similarly, in the present study, the antioxidants and oxidative stress parameters were also assessed following paracetamol-induced liver injury. The histological studies following liver injury were also assessed using H and E staining, Masson's trichrome staining, and periodic acid-Schiff staining. Similarly, the computational approach was used to assess the pharmacokinetic parameters of poncirin and its interaction with various protein targets. Poncirin markedly improved the antioxidant enzymes while attenuated the oxidative stress markers and inflammatory cytokines. Poncirin also markedly improved hematological parameters. Furthermore, poncirin treatment significantly improved the histological parameters using H and E staining, Masson's trichrome, and PAS staining compared to the control. Poncirin treatment also improved the liver function tests and liver synthetic activity compared to paracetamol treated group. The immunohistochemistry analysis revealed significant decrease in the inflammatory signaling protein such as nuclear factor kappa light chain enhancer of activated B cells (NF-κB), Jun N-terminal kinase (JNK), and cyclooxygenase-2 (COX-2) expression level compared to the paracetamol treated group. Computational analysis (molecular docking and molecular dynamic simulation) showed significant binding affinity of poncirin with the NF-κB, JNK, COX-2, IL-1ß, IL-6, and TNF-α via multiple hydrophilic and hydrophobic binds. Similarly, the SwissADME software revealed that poncirin follows various drug-likeness rules and exhibited better pharmacokinetic parameters. Poncirin improved the sign and symptoms associated with liver injury using both in vivo and computational approaches.

Poncirin ameliorates oxygen glucose deprivation/reperfusion injury in cortical neurons via inhibiting NOX4-mediated NLRP3 inflammasome activation.

Poncirin, a natural flavonoid present abundantly in citrus fruits, possesses anti-oxidant and anti-inflammatory activities that contribute to neuroprotection, but its roles and mechanisms in neuronal injury is still poorly understood. In this study, an oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in primary cortical neurons to induce neuronal injury in vitro. Poncirin effectively attenuated OGD/R-induced neuronal damage by enhancing cell viability, restraining lactate dehydrogenase release, and reducing apoptosis of neurons. Poncirin restrained mitochondrial dysfunction and oxidative stress by increasing mitochondrial membrane potential, declining reactive oxygen species production, lessening malondialdehyde generation, and increasing the activities of antioxidant enzymes in OGD/R-treated neurons. Poncirin also repressed inflammatory responses by reducing the secretion of pro-inflammatory factors, and inhibiting NLRP3 inflammasome activation. Importantly, poncirin administration notably abolished OGD/R-induced upregulation of NADPH oxidase 4 (NOX4), and overexpression of NOX4 neutralized poncirin-mediated neuroprotection. In conclusion, poncirin protects cortical neurons from OGD/R injury via inhibiting NOX4/ROS/NLRP3 axis.

Therapeutic Potential of Poncirin Against Numerous Human Health Complications: Medicinal Uses and Therapeutic Benefit of an Active Principle of Citrus Species.

Medicinal plants have been used in the indigenous system of medicine for the treatment of numerous human health complications. Medicinal plants were used for the separation and isolation of pure phytochemical and some of the best examples are tubocurarine, aspirin, morphine, digoxin, atropine, quinine and reserpine. Phytoconstituents are pure, plant-derived, natural chemicals found to be present in medicinal plants and examples are flavonoids, alkaloids and phenolic compounds, etc. In modern medicine, there has been a global growth of herbal medicines due to their nutrition, physical effectiveness and pharmacological activities. Plants have been used in the traditional medicines and modern drug discoveries program. In order to investigate the biological potential of poncirin in modern medicine, here, different scientific data have been analyzed in the present investigation through various literature sources. Detailed pharmacological activities of poncirin were also investigated in the present investigation to reveal the medicinal properties of poncirin in medicine and other allied health sectors. Analytical techniques used for the isolation of poncirin from various medicinal plants have been also presented in this study. Poncirin is a flavanone glycoside found to be present in the Poncirus trifoliata and Citrus reticulate having a bitter taste. The biological importance of poncirin for their anti-inflammatory activity through inhibition of PGE2 and IL-6 production has been investigated in the scientific field. The biological importance of poncirin against bacterial, viral infections, gastric disease and human gastric cancer has been investigated in medicine. Pharmacological data analysis revealed the biological application of poncirin against bone loss, inflammation, colitis, human gastric cancer, gastritis, liver injury and Alzheimer's disease. From the analysis of the presented scientific information of poncirin, it was found that poncirin has significant biological activities and health benefits in the modern health sectors for the treatment of human health complications and could be used as a drug in the future.

Poncirin downregulates ATP-binding cassette transporters to enhance cisplatin sensitivity in cisplatin-resistant osteosarcoma cells.

Poncirin, a flavanone glycoside with bitter taste extracted from dried immature fruit of Poncirus trifoliate, exhibits multiple biological activities including anti-tumor activity. Our study aimed to determine the effect and potential mechanism of poncirin on cisplatin resistance in osteosarcoma (OS) cells. CCK-8, flow cytometry analysis, and caspase-3/7 activity assays were used to evaluate cisplatin sensitivity. The expression changes of multidrug resistance 1 (MDR1), multidrug resistance-associated protein (MRP1), breast cancer resistance protein (BCRP), and phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway-related proteins were detected by RT-qPCR or western blot analyses. Results showed that poncirin exposure enhanced cisplatin sensitivity, promoted apoptosis, and increased caspase-3/7 activity in cisplatin-resistant OS cells. Poncirin decreased the expression levels of MDR1, MRP1, and BCRP, and inhibited the PI3K/Akt signaling in OS cells. Rescue experiments suggested that activation of the PI3K/Akt signaling by 740Y-P abolished poncirin-induced expression reduction of MDR1, MRP1, and BCRP, and attenuated the facilitative effects of poncirin on cisplatin sensitivity and apoptosis in cisplatin-resistant OS cells. In summary, poncirin suppressed cisplatin resistance in cisplatin-resistant OS cells by downregulating the expression of MDR1, MRP1, and BCRP through inhibiting the PI3K/Akt pathway.

Poncirin suppresses lipopolysaccharide (LPS)-induced microglial inflammation and ameliorates brain ischemic injury in experimental stroke in mice.

BACKGROUND: Based on accumulating evidence, excessive activation of microglia-mediated inflammatory responses plays an essential role in ischemic stroke. Poncirin (Pon) exerts anti-hyperalgesic, anti-osteoporotic and anti-tumor effects on various diseases. However, the roles of Pon in microglial activation and the underlying mechanism have not been elucidated. This study aimed to explore whether Pon inhibits lipopolysaccharide (LPS)-induced microglial neuroinflammation and protects against brain ischemic injury in experimental stroke in mice. METHODS: Primary microglia cells were prepared from the cerebral cortices of 1- to 2-day-old C57BL/6J mice. Murine BV2 cells and primary microglia were stimulated with LPS and the effects of a non-cytotoxic concentration of Pon on LPS-stimulated pro-inflammatory factors were measured using real-time PCR and enzyme-linked immunosorbent assays (ELISAs). Western blot analyses were used for mechanistic studies. In an in vivo study, 8-week-old male C57BL/6J mice were subjected to focal cerebral ischemia through middle cerebral artery occlusion (MCAO). Pon (30 mg/kg, i.p.) or the same volume of saline was administered after the MCAO model was established, and the infarct volume was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining. We also evaluated animal behaviours, the expression of pro-inflammatory cytokines and microglial activation in the ischemic hemisphere. RESULTS: Pon prevented the release of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin (IL)-1ß, IL-6 and tumor necrosis factor-alpha (TNF-α) in both BV2 cells and primary microglia stimulated with LPS. The inhibitory effects of Pon were associated with the regulation of the ERK1/2, JNK and nuclear factor kappa B (NF-κB) signaling pathways. In mice that underwent MCAO, Pon administration decreased the lesion size and improved neurological deficits. Furthermore, Pon attenuated the production of inflammatory cytokines mainly by restraining microglial activation after ischemic stroke. CONCLUSIONS: Based on the findings from the present study, Pon provides neuroprotection through its anti-inflammatory effects on microglia and it may be a useful treatment for ischemic stroke.

Poncirin, an orally active flavonoid exerts antidiabetic complications and improves glucose uptake activating PI3K/Akt signaling pathway in insulin resistant C2C12 cells with anti-glycation capacities.

Poncirin, a natural flavanone glycoside present abundantly in many citrus fruits, contains an extensive range of biological activities. However, the antidiabetic mechanism of poncirin is unexplored yet. In this study, we examined the anti-diabetic prospective of poncirin by evaluating its ability to inhibit protein tyrosine phosphatase 1B (PTP1B), α-glucosidase, human recombinant AR (HRAR), rat lens aldose reductase (RLAR), and advanced glycation end-product (AGE) formation (IC50 = 7.76 ± 0.21, 21.31 ± 1.26, 3.56 ± 0.33, 11.91 ± 0.21, and 3.23 ± 0.09 µM, respectively). Kinetics data and docking studies showed the lowest binding energy and highestaffinityforthemixed and competitivetypeof inhibitorsof poncirin. Moreover, the molecular mechanisms underlying the antidiabetic outcomes of poncirin in insulin resistant C2C12 skeletal muscle cells were explored, which significantly increased glucose uptake and decreased the expression of PTP1B in C2C12 cells. Consequently, poncirin increased GLUT-4 expression level by activating the IRS-1/PI3K/Akt/GSK-3 signaling pathway. Moreover, poncirin (0.5-50 µM) remarkably inhibited the formation of fluorescent AGE, nonfluorescent CML, fructosamine, and ß-cross amyloid structures in glucose-fructose-induced BSA glycation during 4 weeks of study. Poncirin also notably prevented protein oxidation demonstrated with decreasing the protein carbonyl and the consumption of protein thiol in the dose-dependent manner. The results clearly expressed the promising activity of poncirin for the therapy of diabetes and its related complications.

Poncirin attenuates CCL4-induced liver injury through inhibition of oxidative stress and inflammatory cytokines in mice.

BACKGROUND: In the present study, the poncirin which is flavonoid-7-o-glycosides (isolated from the Poncirus trifoliata) in nature was evaluated against the Carbon tetra chloride (CCL4)-induced liver injury. The poncirin have been reported for various anti-inflammatory, analgesic activity etc. Based on the previous studies it was anticipated that the poncirin will ameliorate CCL4-induced liver injury. METHODS: The CCL4-induced acute and chronic liver injury model (albino BALB/c mice) was used. Following the induction of the liver injury various parameters such as food and water intake, body weight and weight to dry ratio changes were assessed. Furthermore, various hematological, biochemical parameters and histological studies such as hemotoxylin and eosin (H and E) staining were performed. The poncirin treatment was also evaluated against the pro-inflammatory cytokines such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) using enzyme link immunosorbant assay (ELISA). The Swiss Target prediction software was used to investigate interaction of the poncirin on the various hepatic enzymes. RESULTS: The poncirin treatment markedly improved the behavioral parameters such as food and water intake. The liver weight variation was attenuated and total body was improved markedly. The hematological and biochemical parameters were significantly improved compared to the CCL4 treated groups. The anti-oxidants were induced, while oxidative stress markers were reduced promisingly. The H and E staining showed that poncirin treatment significantly improved the histology of liver compared to the CCL4 treated group. Furthermore, the poncirin treatment also evidently decreased the inflammatory mediators. CONCLUSIONS: The poncirin treatment showed marked improvement in behavioral, biochemical and histological parameters following CCL4-induced liver injury. Additionally, the poncirin treatment also markedly improved the antioxidant enzymes, attenuated the oxidative stress markers and inflammatory cytokines.

Poncirin Inhibits Osteoclast Differentiation and Bone Loss through Down-Regulation of NFATc1 In Vitro and In Vivo.

Activation of osteoclast and inactivation of osteoblast result in loss of bone mass with bone resorption, leading to the pathological progression of osteoporosis. The receptor activator of NF-κB ligand (RANKL) is a member of the TNF superfamily, and is a key mediator of osteoclast differentiation. A flavanone glycoside isolated from the fruit of Poncirus trifoliata, poncirin has anti-allergic, hypocholesterolemic, anti-inflammatory and anti-platelet activities. The present study investigates the effect of poncirin on osteoclast differentiation of RANKL-stimulated RAW264.7 cells. We observed reduced formation of RANKL-stimulated TRAP-positive multinucleated cells (a morphological feature of osteoclasts) after poncirin exposure. Real-time qPCR analysis showed suppression of the RANKL-mediated induction of key osteoclastogenic molecules such as NFATc1, TRAP, c-Fos, MMP9 and cathepsin K after poncirin treatment. Poncirin also inhibited the RANKL-mediated activation of NF-κB and, notably, JNK, without changes in ERK and p38 expression in RAW264.7 cells. Furthermore, we assessed the in vivo efficacy of poncirin in the lipopolysaccharide (LPS)-induced bone erosion model. Evaluating the micro-CT of femurs revealed that bone erosion in poncirin treated mice was markedly attenuated. Our results indicate that poncirin exerts anti-osteoclastic effects in vitro and in vivo by suppressing osteoclast differentiation. We believe that poncirin is a promising candidate for inflammatory bone loss therapeutics.

Impact of extraction processes on phytochemicals content and biological activity of Citrus × clementina Hort. Ex Tan. leaves: New opportunity for under-utilized food by-products.

Plants are a rich source of natural bioactive compounds with a wide range of applications in the food and pharmaceutical industries. Citrus × clementina leaves extracts and essential oils may be a potential candidate for formulation of products characterized by hypoglycaemic, antioxidant and anti-browning properties. C. × clementina leaves collected in three different areas in Calabria (South Italy) were extracted by Soxhlet apparatus, maceration, Ultrasound assisted maceration, and hydrodistillation. Hesperidin, tangeritin, and sinensetin were identified by HPLC-DAD analysis as dominant constituents of the extracts. The absence of coumarins and furanocoumarins was demonstrated. GC-MS analyses of essential oils evidenced the presence of sabinene, linalool, and (E)-ß-ocimene as main compounds. Based on RACI and GAS values calculated by the integration of data obtained by DPPH, ABTS, FRAP and ß-carotene bleaching methods, hydroalcoholic extract obtained by Ultrasound assisted maceration of the leaves collected in Corigliano Calabro showed the highest antioxidant activity. Ultrasound assisted hydroalcoholic extract of Cetraro leaves revealed the highest α-amylase inhibitory activity (IC50 of 64.37 µg/ml). Promising results of C. × clementina extracts as tyrosinase inhibitors were also obtained. To evaluate the relationship between identified compounds and bioactivity PCA was performed. Taking into account results obtained by this study, C. × clementina leaves that were considered Citrus-by-products could be utilized for formulation of food additives, nutraceuticals and functional foods.

Anti-hyperalgesic properties of a flavanone derivative Poncirin in acute and chronic inflammatory pain models in mice.

BACKGROUND: Poncirin is flavanone derivative (isolated from Poncirus trifoliata) with known pharmacological activities such as anti-tumor, anti-osteoporotic, anti-inflammatory and anti-colitic. The present study aimed to explore the anti-allodynic and anti-hyperalgesic potentials of poncirin in murine models of inflammatory pain. METHODS: The analgesic potential of poncirin was evaluated in formalin-, acetic acid-, carrageenan- and Complete Freund's Adjuvant (CFA)-induced inflammatory pain models in mice. Anti-allodynic and anti-hyperalgesic activities were measured using Von Frey filaments, Randall Selitto, hotplate and cold acetone tests. The serum nitrite levels were determined using Griess reagent. The Quantitative Real-time PCR (qRT-PCR) was performed to assess the effect of poncirin on mRNA expression levels of inflammatory cytokines and anti-oxidant enzymes. RESULTS: Intraperitoneal administration of poncirin (30 mg/kg) markedly reduced the pain behavior in both acetic acid-induced visceral pain and formalin-induced tonic pain models used as preliminary screening tools. The poncirin (30 mg/kg) treatment considerably inhibited the mechanical hyperalgesia and allodynia as well as thermal hyperalgesia and cold allodynia. The qRT-PCR analysis showed noticeable inhibition of pro-inflammatory cytokines (mRNA expression levels of TNF-α, IL-1ß and IL-6) (p < 0.05) in poncirin treated group. Similarly, poncirin treatment also enhanced the mRNA expressions levels of anti-oxidant enzymes such as transcription factor such as nuclear factor (erythroid-derived 2)-like 2 (Nrf2) (p < 0.05), heme oxygenase (HO-1) (p < 0.05) and superoxide dismutase (SOD2) (p < 0.05). Chronic treatment of poncirin for 6 days did not confer any significant hepatic and renal toxicity. Furthermore, poncirin treatment did not altered the motor coordination and muscle strength in CFA-induced chronic inflammatory pain model. CONCLUSION: The present study demonstrated that poncirin treatment significantly reduced pain behaviors in all experimental models of inflammatory pain, suggesting the promising analgesic potential of poncirin in inflammatory pain conditions.

Ponciretin attenuates ethanol-induced gastric damage in mice by inhibiting inflammatory responses.

BACKGROUND: Poncirin (PO) and isosakuranetin (or ponciretin [PT]) are compounds found in fruits of the genus Citrus. They are frequently used in traditional Chinese medicine for the treatment of inflammation and asthma. Therefore, we examined their anti-gastritis effects in vitro and in vivo. METHODS: The anti-inflammatory effects of PO and PT were examined using ethanol- or LPS-stimulated KATO III cells. Gastritis was induced in ICR mice via intragastric injection of absolute ethanol. Levels of inflammatory markers were measured by enzyme-linked immunosorbent assay, immunoblotting, and quantitative polymerase chain reaction. RESULTS: Treatment with PT or PO inhibited the secretion of interleukin (IL)-8 and tumor necrosis factor (TNF) in ethanol- or LPS-stimulated KATO III cells. They also reduced the activation of nuclear factor kappa B (NF-κB). Pre-treatment with PT or PO significantly protected against ethanol-induced hemorrhagic gastritis, characterized by edema, tissue erosions, and mucosal friability in mice. Treatment with PT or PO suppressed ethanol-induced NF-κB activation and the release of TNF, IL-8, and IFN-γ. The protective effect of PT was greater than that of PO and comparable to ranitidine, a positive control. CONCLUSION: PT may attenuate ethanol-induced gastritis by inhibiting the infiltration of immune cells, including neutrophils, via the regulation of CXCL4 (or IL-8) secretion and the activation NF-κB.

Poncirin and its metabolite ponciretin attenuate colitis in mice by inhibiting LPS binding on TLR4 of macrophages and correcting Th17/Treg imbalance.

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Poncirus trifoliate, which contains poncirin as a main constituent, is frequently used in the traditional Chinese medicine for inflammation, asthma, and infection diseases. AIM OF THE STUDY: To examine anti-colitic effects of poncirin and ponciretin, a metabolite of poncirin by gut microbiota. MATERIALS AND METHODS: Colitis was induced in mice by the intrarectal injection of 2,4,6-trinitrobenzenesulfonic acid (TNBS). Inflammatory markers were analyzed by enzyme-linked immunosorbent assay, immunoblotting, quantitative polymerase chain reaction, confocal microscopy, and flow cytometry. Peritoneal macrophages were isolated from mice stimulated with 4% thioglycolate. RESULTS: Poncirin was metabolized to ponciretin in vitro and in vivo by gut microbiota of mice. Orally administered poncirin and ponciretin suppressed TNBS-induced colitis in mice: these inhibited colon shortening, myeloperoxidase activity, NF-κB activation, and Th17 cell differentiation, but increased occludin, claudin-1, and ZO-1 expressions and Treg cell differentiation. Poncirin and ponciretin suppressed the differentiation of splenocytes into Th17 cells and expression of IL-17 and Foxp3 in vitro, as well as the activation of macrophages stimulated with lipopolysaccharide (LPS) by inhibiting the binding of LPS on TLR4 of macrophages. These increased the differentiation of splenocytes into Treg cells. The ant-inflammatory effect of ponciretin was superior to that of poncirin. CONCLUSION: Orally administered poncirin is metabolized to ponciretin by gut microbiota and poncirin and ponciretin attenuates colitis by suppressing NF-κB activation through the inhibition of LPS binding on macrophages and correcting Th17/Treg cell imbalance.

Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand.

Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies' results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.