• Journal of Microbiology and Biotechnology
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• 제32권2호
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• pp.263-267
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• 2022

The aim of this study was to determine whether the antibacterial activity of chitosan-modified Fe₃O₄ (CS@Fe₃O₄) nanomaterials against Acinetobacter baumannii (A. baumannii) is mediated through changes in biofilm formation and reactive oxygen species (ROS) production. For this purpose, the broth dilution method was used to examine the effect of CS@Fe₃O₄ nanoparticles on bacterial growth. The effects of CS@Fe₃O₄ nanoparticles on biofilm formation were measured using a semi-quantitative crystal violet staining assay. In addition, a bacterial ROS detection kit was used to detect the production of ROS in bacteria. The results showed that CS@Fe₃O₄ nanoparticles had a significant inhibitory effect on the colony growth and biofilm formation of drug-resistant A. baumannii (p < 0.05). The ROS stress assay revealed significantly higher ROS levels in A. baumannii subjected to CS@Fe₃O₄ nanoparticle treatment than the control group (p < 0.05). Thus, we demonstrated for the first time that CS@Fe₃O₄ nanoparticles had an inhibitory effect on A. baumannii in vitro, and that the antibacterial effect of CS@Fe₃O₄ nanoparticles on drug-resistant A. baumannii was more significant than on drug-sensitive bacteria. Our findings suggest that the antibacterial mechanism of CS@Fe₃O₄ nanoparticles is mediated through inhibition of biofilm formation in drug-resistant bacteria, as well as stimulation of A. baumannii to produce ROS. In summary, our data indicate that CS@Fe₃O₄ nanoparticles could be used to treat infections caused by drug-resistant A. baumannii.

• 동의생리병리학회지
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• 제26권1호
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• pp.74-80
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• 2012

Candida albicans is a common opportunistic pathogen and is frequently associated with biofilm formation occurring on the surfaces of host tissues and medical devices. On account of the distinct resistance of C. albicans biofilms to the conventional antifungal agents, new strategies are required to cope with these infections. The root of Polygonum cuspidatum has been used for medicinal purposes in East Asia. The aim of this study was to assess the anticandidal potential of the P. cuspidatum ethanol extract by evaluating biofilm formation, integrity of the cell membranes of C. albicans and adhesion of C. albicans cells to polystyrene surfaces. The growth and development of the biofilm was assessed using an XTT reduction assay, and the extract (0.39 mg/ml) significantly reduced ($41.1{\pm}17.8%$) biofilm formation of 11 C. albicans strains. The extract damaged the cell membranes of C. albicans and remarkably inhibited cell adhesion to polystyrene surfaces. The plant extract displayed fungistatic activity without significant hemolytic activity. Based on the results of this study, the P. cuspidatum extract has promising potential for use in treating biofilm-associated Candida infection.

• Advances in Traditional Medicine
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• 제8권1호
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• pp.39-46
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• 2008

In the Indian traditional medicine, Lippia nodiflora (Verbenaceae) whole plant is claimed to possess powerful diuretic activity. However, the diuretic potential of this plant is not yet investigated. The aim of this study was to evaluate the diuretic potential of methanol extract of Lippia nodiflora (MELN) in rats. Control (0.9% saline solution, 25 ml/kg, b.w) or urea (1 g/kg b.w) or frusemide (5 mg/kg b.w) and different concentrations of MELN (200 and 400 mg/kg b.w) were intraperitoneally administered (n = 6 per each treatment group) to hydrated rats and their urine output was monitored over a period of 5 h and 24 h after drug administration. The diuretic responses with its electrolyte excretion potency of the extract were highly remarkable in comparison with control animals. The extract at doses of 200 and 400 mg/kg shows a significant increase in volume of urine with increase in $Na^{+}$, $Ca^{2+}$ and $Cl^{-}$ excretion accompanied by the excretion of $K^{+}$ in dose dependent manner. This study suggests that the active component(s) in MELN had similar diuretic effect to that of frusemide. These results validate the traditional use of Lippia nodiflora as a diuretic agent.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.3901-3905
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• 2015

Objective: Our aim was to investigation the roles of MHC class I chain-related gene A(MICA) and natural killer cell group 2D(NKG2D) in human renal cancer cells. Materials and Methods: The expression of membrane MICA (mMICA) on renal cells and NKG2D on NK cells were detected by flow cytometry (FCM); the content of sMICA were detected by enzyme linked immunosorbent assay (ELISA) and the distribution of mMICA on renal tumor tissues by immunohistochemistry; the interaction between MICA and NKG2D was observed by antibody closed method. Results: Our results showed that the expression of mMICA in renal cancer tissues was significantly higher than in controls, where the soluble MICA was not expressed. Cytotoxic activity of NK cells was significantly reduced after exposure to NKG2D and MICA antibodies (P<0.05), and serum containing sMICA can obviously lower the function of NKG2D (P<0.05). Conclusions: The interaction of mMICA and NKG2D play important roles in mediation of cytotoxicity of NK cells in RCC. On the other hand, sMICA may mediate tumor immune escape through down- regulated NKG2D expression.

• 대한의생명과학회지
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• 제11권2호
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• pp.211-219
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• 2005

Trigeminovascular system plays an important role for the cerebral memodynamics. The aim of this study was to investigate the alterations in cerebrovascular reactivity by trigeminovascular system injury in rats. Trigeminovascular system of male Sprague-Dawley rats was injured by either denervation of nasocilliary nerve or neonatal capsaicin treatment. Trigeminovascular system was stimulated by controlled hemorrhagic hypotension or somatosensory (whisker) stimulation. Changes in regional cerebral blood flow (rCBF) and pial arterial diameter were continuously measured by laser-Doppler flowmetry and videomicroscopy, respectively. Nitric oxide synthase (NOS) activity in cerebral cortex was determined by measuring the conversion of $L-^3H-arginine\;to\;L-^3H-citrulline$. Cyclic GMP levels in cerebral cortex and pial artery were determined using the cyclic GMP $^{125}I$ scintillation proximity assay system. rCBF autoregulation was impaired or almost abolished by trigeminovascular system injury. rCBF response to whisker stimulation was significantly attenuated by trigeminovascular system injury. NOS activity as well as cyclic GMP level in cerebral cortex and pial artery were significantly reduced in the group of trigeminovascular system injury. These results suggest that trigeminovascular system injury causes prominent alterations in cerebrovascular reactivity, and that NO, which is generated by neuronal NOS in the trigeminovascular system, is implicated in the regulation of rCBF.

• Asian-Australasian Journal of Animal Sciences
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• 제33권3호
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• pp.398-407
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• 2020

Objective: The Yip1 domain family (YIPF) proteins were proposed to function in endoplasmic reticulum (ER) to Golgi transport and maintenance of the morphology of the Golgi, which were homologues of yeast Yip1p and Yif1p. YIPF3, the member 3 of YIPF family was a homolog of Yif1p. The aim of present study was to investigate the expression and regulation mechanism of porcine YIPF3. Methods: Quantitative realtime polymerase chain reaction (qPCR) was used to analyze porcine YIPF3 mRNA expression pattern in different tissues and pig kidney epithelial (PK15) cells stimulated by polyinosine-polycytidylic acid (poly [I:C]). Site-directed mutations combined with dual luciferase reporter assays and electrophoretic mobility shift assay (EMSA) were employed to reveal transcription regulation mechanism of porcine YIPF3. Results: Results showed that the mRNA of porcine YIPF3 (pYIPF3) was widely expressed with the highest levels in lymph and lung followed by spleen and liver, while weak in heart and skeletal muscle. Subcellular localization results indicated that it expressed in Golgi apparatus and plasma membranes. Upon stimulation with poly (I:C), the level of this gene was dramatically up-regulated in a time- and concentration-dependent manner. pYIPF3 core promoter region harbored three cis-acting elements which were bound by ETS proto-oncogene 2 (ETS2), zinc finger and BTB domain containing 4 (ZBTB4), and zinc finger and BTB domain containing 14 (ZBTB14), respectively. In which, ETS2 and ZBTB4 both promoted pYIPF3 transcription activity while ZBTB14 inhibited it, and these three transcription factors all played important regulation roles in tumorigenesis and apoptosis. Conclusion: The pYIPF3 mRNA expression was regulated by ETS2, ZBTB4, and ZBTB14, and its higher expression in immune organs might contribute to enhancing ER to Golgi transport of proteins, thus adapting to the immune response.

• Nutrition Research and Practice
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• 제13권5호
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• pp.384-392
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• 2019

BACKGROUND/OBJECTIVES: Enteral nutrition formulas with immune-enhancing nutrients, such as n-3 fatty acids, may manage patients' nutritional status and pathophysiological processes. The aim of our study was to investigate natural killer (NK) cell activity alterations and related cytokine changes resulting from feeding with soybean oil-containing enteral nutrition formula (control group) and plant-derived n-3 fatty acid-enriched enteral nutrition formula. SUBJECTS/METHODS: Subjects participated for 14 consecutive days and consumed enteral formula containing canola and flaxseed oil (n3EN, test group) in nonsurgical patients hospitalized for rehabilitation. Blood samples were collected on the first day and 14 days after the consumption of each formula daily, and anthropometric parameters were collected. Hematology and biochemical values were analyzed, and NK cell activities and serum cytokine concentration were measured. A total of sixty subjects were included in the analysis, excluding dropouts. RESULTS: No significant differences were found in biochemical parameters. The n3EN group's NK cell activities at effector:tumor cell ratios of 10:1, 5:1, 2.5:1 and 0.625:1 were significantly higher than those of the control group after two weeks (P < 0.05). However, there were no statistically significant differences in serum cytokine interleukin (IL)-12, $interferon-{\gamma}$, $IL-1{\beta}$, IL-6 and tumor necrosis $factor-{\alpha}$ values between the two groups. CONCLUSIONS: In conclusion, this study elucidates the beneficial effects of plant-derived n-3 fatty acid supplementation in enteral formula on NK cell activity.

• 대한약침학회지
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• 제25권3호
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• pp.242-249
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• 2022

Objectives: The aim of this work is to evaluate the in vitro antioxidant, hypoglycemic, and antiobesity effects of Euphorbia resinifera extracts and investigate the phenolic constituents and the toxicity of these extracts. Methods: Phytochemical screening was performed to detect polyphenols and flavonoids. Antioxidant activity was evaluated by four methods (DPPH, ABTS, H₂O₂, and xanthine oxidase inhibition). The hypoglycemic effect was determined by the inhibition of α-amylase and α-glucosidase enzymes in vitro and via a starch tolerance study in normal rats. The antiobesity effect was estimated by in vitro inhibition of lipase. Results: Phytochemical screening revealed that the ethanolic extract was rich in polyphenols (99 ± 0.56 mg GEA/g extract) and tannins (55.22 ± 0.17 mg RE/g extract). Moreover, this extract showed higher antioxidant activity in different tests: the DPPH assay (IC₅₀ = 53.81 ± 1.83 ㎍/mL), ABTS assay (111.4 ± 2.64 mg TE/g extract), H₂O₂ (IC₅₀ = 98.15 ± 0.68 ㎍/mL), and xanthine oxidase (IC₅₀ = 10.26 ± 0.6 ㎍/mL). With respect to hypoglycemic effect, the aqueous and ethanolic extracts showed IC₅₀ values of 119.7 ± 2.15 ㎍/mL and 102 ± 3.63 ㎍/mL for α-amylase and 121.4 ± 1.88 and 56.6 ± 1.12 ㎍/mL for α-glucosidase, respectively, and the extracts lowered blood glucose levels in normal starch-loaded rats. Additionally, lipase inhibition was observed with aqueous (IC₅₀ = 25.3 ± 1.53 ㎍/mL) and ethanolic (IC₅₀ = 13.7 ± 3.03 ㎍/mL) extracts. Conclusion: These findings show the antioxidant, hypoglycemic, and hyperlipidemic effects of E. resinifera extracts, which should be investigated further to validate their medicinal uses and their pharmaceutical applications.

• Journal of Ginseng Research
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• 제43권4호
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• pp.600-605
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• 2019

Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside $LS_1$ (1) and 5,6-didehydroginsenoside $Rg_3$ (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with $IC_{50}$ of $37.38{\mu}M$ compared with that of NG-monomethyl-L-arginine ($IC_{50}=90.76{\mu}M$). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin $E_2$ and tumor necrosis factor-${\alpha}$. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

• 대한약침학회지
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• 제27권3호
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• pp.211-222
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• 2024

Objectives: Tilia viridis (Bayer) Simonk. (Malvaceae) is widely distributed in Argentina and employed for its tranquilizing properties. Other species of the genus (Tilia europaea L., Tilia cordata Mill., Tilia platyphyllos Scop.) have been traditionally used for the treatment of epilepsy. Epilepsy affects approximately 65 million people worldwide and is characterized by an imbalance between excitatory and inhibitory processes in the brain, leading to unpredictable, unprovoked, recurrent seizures. Current pharmacological interventions often present mild to moderately severe side effects. Epilepsy has been associated with oxidative and nitrative stress as well as neuroinflammation. Herbal medicine therapies may offer new treatment options with multi-target antioxidant and anticonvulsant effects for patients whose seizures remain uncontrolled, potentially providing cost-effective solutions for individuals worldwide suffering from uncontrolled epilepsy.The aim of this study was to demonstrate the anticonvulsant activity of a standardized T. viridis aqueous extract (TE). Methods: Study of the constituents of TE, TE's antioxidant and anticonvulsant activities and toxicity, and analysis of the possible relation between the potential activities and the compounds present in the extract. In order to demonstrate TE's anticonvulsant activity a zebrafish model was used. The study also assessed TE's toxicity and antioxidant activity. To standardize the extract, total polyphenols and flavonoids were quantified and specific flavonoids were identified and quantified using HPLC-MS/MS and HPLC-UV. Results: TE exhibited anticonvulsant activity at low concentrations and demonstrated antioxidant effects by scavenging free radicals, exhibiting superoxide dismutase and peroxidase-like activities, as well as inhibiting lipoperoxidation. These actions can be attributed to the presence of polyphenols, particularly flavonoids. Conclusion: TE holds promise as a complementary herbal medicine in the treatment of epilepsy and may also offer benefits for other neuropathies associated with oxidative stress, such as Parkinson's disease and Alzheimer's disease.