Prevalence and determinants of constipation in children in Asia: a systematic review and meta-analysis

Background

Constipation is prevalent worldwide, significantly increasing healthcare costs and diminishing the quality of life in children affected. Current studies have yielded mixed results regarding the factors associated with constipation, and mainly focusing on patients outside of Asia. Moreover, most of these studies lack focus on the paediatric population. This study aimed to identify the prevalence and associated factors of constipation among children in Asia.

Methods

In this systematic review and meta-analysis, we systematically searched PubMed, Scopus, and Cochrane for cohort and cross-sectional studies published from database inception up to October 12, 2022, and continued with manual searching until September 2, 2023. Eligible studies were those that included children in Asia aged 0-18 years old suffering from idiopathic constipation, with prevalence value provided in the English abstract. The analysis included clinical and general population. Children with organic constipation, who had undergone gastrointestinal surgery, or with congenital defects were excluded, as these factors affect the incidence of constipation. Data included in the analysis were extracted from published reports only. The extracted data were pooled using random-effects model to analyse the prevalence of constipation in children in Asia. This study is registered with PROSPERO, CRD42022367122.

Findings

Out of 4410 systematically searched studies and 36 manually searched ones, a total of 50 studies were included in the final analysis, encompassing data from 311,660 children residing in Asia. The pooled prevalence of constipation was 12.0% (95% CI 9.3-14.6%, I2 = 99.8%). There was no significant difference in constipation prevalence observed by sex and geographical location. Nonetheless, adolescents and children aged 1-9 years exhibited a significantly higher prevalence constipation compared to infants (p < 0.0001) Additionally, significant differences in constipation rates were observed across various diagnostic methods, population sources, and mental health conditions.

Interpretation

Despite the high heterogeneity resulting from varying diagnostic tools or definitions used among studies, our review adds to the literature on constipation among children in Asia. It reveals a notably high prevalence of constipation in this demographic. Diagnostic methods, age, and compromised mental health emerged as significant influencers of constipation among children in Asia, highlighting potential strategies to mitigate constipation prevalence in children in Asia.

Funding

The National Science and Technology Council, Taiwan.

Punicalagin from pomegranate ameliorates TNF-α/IFN-γ-induced inflammatory responses in HaCaT cells via regulation of SIRT1/STAT3 axis and Nrf2/HO-1 signaling pathway

Punicalagin (PUN) was isolated from the peel of pomegranate (Punica granatum L.), is a polyphenol with anti-inflammatory, hepatoprotective, and antioxidant activities. However, it remains unclear whether PUN alleviates the inflammation and anti-inflammatory mechanisms in pro-inflammatory cytokines-induced human keratinocyte HaCaT cells. Here, we investigated that tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) mixture-stimulated HaCaT cells were treated with various concentrations of PUN, followed by analyzed the expression of inflammation-related mediators and evaluate anti-inflammatory-related pathways. Our results demonstrated that PUN ≤ 100 μM did not reduce HaCaT cell viability, and PUN ≥ 3 μM was sufficient to decrease interleukin-6 (IL-6), IL-8, monocyte chemoattractant protein-1 (MCP-1), chemokine ligand 5 (CCL5), CCL17 and CCL20 concentrations. We found that PUN ≥ 10 μM and ≥ 3 μM significantly increased sirtuin 1 (SIRT1) expression and inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation, respectively. PUN downregulated inflammation-related proteins cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), enhanced nuclear factor erythroid-2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1) expression. Moreover, PUN decreased intercellular adhesion molecule-1 (ICAM-1) expression and inhibited monocyte adhesion to inflamed HaCaT cells. PUN also suppressed inflammatory-related pathways, including mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways in TNF-α/IFN-γ- stimulated HaCat cells. Collectively, there is significant evidence that PUN has effective protective defenses against TNF-α/IFN-γ-induced skin inflammation by enhancing SIRT1 to mediate STAT3 and Nrf2/HO-1 signaling pathway.

Therapeutic Application of Dendrobium fimbriatum Hook for Retinopathy Caused by Ultraviolet Radiation and Chemotherapy Using ARPE-19 Cells and Mouse Retina

Retinopathy caused by ultraviolet radiation and cancer chemotherapy has increased dramatically in humans due to rapid environmental and social changes. Therefore, it is very important to develop therapeutic strategies to effectively alleviate retinopathy. In China, people often choose dendrobium to improve their eyesight. In this study, we explored how Dendrobium fimbriatum extract (DFE) protects ARPE-19 cells and mouse retinal tissue from damage of ultraviolet (UV) radiation and chemotherapy. We evaluated the antioxidant capacity of DFE using the 1,1-diphenyl-2-trinitophenylhydrazine (DPPH) assay. The protective effects of DEF from UV- and oxaliplatin (OXA)-induced damage were examined in ARPE-19 cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and immunofluorescence (IF) stains, and in mouse retinal tissue using immunohistochemistry (IHC) stains. Our results show that DFE has excellent antioxidant capacity. The ARPE-19 cell viability was decreased and the F-actin cytoskeleton structure was damaged by UV radiation and OXA chemotherapy, but both were alleviated after the DFE treatment. Furthermore, DFE treatment can alleviate OXA chemotherapy-induced reduced expressions of rhodopsin and SOD2 and increased expressions of TNF-α and caspase 3 in mouse retinal tissue. Thus, we suggest that DFE can act as suitable treatment for retinopathy through reducing oxidative stress, inflammation, and apoptosis.

Glycine-rich peptides from fermented Chenopodium formosanum sprout as an antioxidant to modulate the oxidative stress

Rhizopus oligosporus was utilized in the solid-state fermentation of Chenopodiumformosanumsprouts (FCS) in a bioreactor. Subsequently, the antioxidant activity of food proteins derived from FCS was investigated. Results showed that glycine-rich peptide (GGGGGKP, G-rich peptide), identified from the <2 kDa FCS proteins, had antioxidant values. According to SwissADME, AllerTOP, ToxinPred, and BIOPEP-UWM analyses, G-rich peptide was identified as safe, non-toxic, and non-allergenic. Afterward, the peptide was examined using in silico and in vitro studies to evaluate its potential alleviating oxidative stress caused by particulate matter. This study proposed plausible mechanisms that involve the binding of G-rich peptide which inhibited phosphorylation of the v-rel avian reticuloendotheliosis viral oncogene homologA(RELA) subunit onNF-κB pathway. The inhibition then resulted in down regulation of NF-κB transcription and genetic expression of inflammatory responses. These findings suggested that G-rich peptide from FCS proteins can potentially alleviate oxidative stress.

Alleviative Effect of Ficus formosana Extract on Peripheral Neuropathy in Ovariectomized Diabetic Mice

In diabetes mellitus, Ficus formosana has been reported to ameliorate blood sugar levels and inhibit inflammation through its polyphenol and flavonoid contents. However, its effect on diabetic peripheral neuropathy (DPN) remains unknown. This study aimed to investigate the effect of Ficus formosana extract (FFE) on DPN in ovariectomized diabetic mice. Ovariectomized female C57BL/6J mice fed a high-fat diet plus streptozotocin injections to induce type 2 diabetes were orally administered FEE at 20 or 200 mg/kg BW daily, for 6 weeks. To evaluate the pain responses in the paws of the mice, a von Frey filament test and a thermal hyperalgesia test were performed. Additionally, the intraepidermal and sciatic nerve sections were examined, along with an assessment of inflammation- and pain response-related mRNA expression in the paws of the mice. The results showed that the oral administration of both 20 and 200 mg/kg BW FEE significantly alleviated the hypersensitivity of the paw and the abnormal proliferation and rupture of the C fiber, and reduced the mRNA expression of interleukin-1β, interleukin-6, interferon-γ, cyclooxygenase-2, and voltage-gated sodium channel 1.8 in the sciatic nerve of ovariectomized diabetic mice. We propose that FFE ameliorates peripheral neuropathy by suppressing oxidative damage in ovariectomized diabetic mice.

Alleviating Effects of Ovatodiolide and Antcin K Supplements on High-Fat Diet-Induced Cardiovascular Dysfunction in ApoE-Knockout Mice by Attenuating Oxidative Stress

A high-fat diet (HFD) is a major risk factor for cardiovascular diseases. Many pure compounds have been demonstrated to be effective in treating cardiovascular diseases. In this study, we investigated the alleviating effects of oral ovatodiolide and antcin K (OAK) supplements on HFD-induced cardiovascular dysfunction in apolipoprotein E (ApoE)-knockout mice. Cardiovascular dysfunction was induced in ApoE-knockout mice by feeding them an HFD for 12 weeks. The degree of cardiovascular dysfunction was assessed through echocardiography, hematological and biochemical analyses, and immunofluorescence and immunohistochemical staining. The HFD-fed mice exhibited cardiovascular dysfunction-abnormal blood biochemical index. The arterial wall tissue exhibited the marked deposition of lipids, upregulated expression of vascular cell adhesion molecule-1 and CD36 receptors, and downregulated expression of the ABCA1 receptor. Macrophages isolated from the peritoneal cavity of the mice exhibited increased levels of lipid accumulation, reactive oxygen species, and CD11b expression but reduced mitochondrial membrane potential. The expression of superoxide dismutase 2 was downregulated and that of tumor necrosis factor-α was upregulated in the myocardial tissue. Oral OAK supplements twice a day for 12 weeks significantly mitigated HFD-induced cardiovascular dysfunction in the experimental mice. Oral OAK supplements appear to be a promising strategy for treating HFD-induced cardiovascular dysfunction. The underlying mechanisms may involve the reduction of lipid accumulation in the artery and oxidative stress and inflammation in the cardiovascular tissue.

Therapeutic Effects of Plant Extracts of Anoectochilus roxburghii on Side Effects of Chemotherapy in BALB/c Breast Cancer Mice

Breast cancer is the most common cancer in women, and chemotherapy is an effective treatment. However, chemotherapy often causes adverse side effects such as cardiotoxicity, myelosuppression, immunodeficiency, and osteoporosis. Our study focused on the alleviating effects of Anoectochilus roxburghii extracts (AREs) on the adverse side effects of chemotherapy in mice with breast cancer. We individually evaluated the antioxidant capacity and cytotoxicity of the AREs using DPPH and MTT assays. We also examined the effects of the AREs on intracellular F-actin, reactive oxygen species (ROS), and the mitochondrial membrane potential (MMP) of 4T1 cancer cells before and after doxorubicin (DOX) treatment. Our results showed that ARE treatment enhanced the effects of DOX chemotherapy by promoting cell morphology damage, oxidative stress, and ROS generation, as well as by reducing MMP in the 4T1 breast cancer cells. By using BALB/c mice with breast cancer with DOX treatment, our results showed that the DOX treatment reduced body weight, blood pressure, and heart rate and induced myelosuppression, immunodeficiency, cardiotoxicity, and osteoporosis. After oral ARE treatment of BALB/c mice with breast cancer, the chemotherapeutic effects of DOX were enhanced, and the adverse side effects of DOX chemotherapy were alleviated. Based on the above results, we suggest that AREs can be used as an adjuvant reliever to DOX chemotherapy in BALB/c mice with breast cancer.

Botanical Antcin K Alleviates High-Fat Damage in Palm Acid Oil-Treated Vascular Endothelial Cells and Macrophages

Lipid metabolism disorder is the most critical risk factor for atherosclerosis, and the process involves lipid deposition in the arterial intima. In Taiwan, antcin K, an active triterpenoid from the fruiting bodies of Antrodia camphorata, has been considered a potential lipid-lowering agent. Despite this, the possible therapeutic mechanisms of antcin K remain unclear. To explore the crucial role of botanical antcin K in reducing atherosclerotic plaque, we used SVEC4-10 vascular endothelial cells and RAW264.7 macrophages with palm acid oil-induced high-fat damage as our cell models. Our results showed through using the DPPH assay that antcin K had excellent free radical scavenging ability. Antcin K treatment can significantly alleviate the high-fat damage and reduce the levels of inflammatory factors of TNF-α and IL-1β in vascular endothelial cells and macrophages, as shown through MTT assay and ELISA. Furthermore, antcin K treatment can effectively enhance migration ability and clear lipid deposition in macrophages, as shown by using cell migration assay and oil red O staining. When stained with immunofluorescence, antcin K was shown to significantly decrease the expression of adhesion molecules of vascular cell adhesion molecule 1 (VCAM-1) in vascular endothelial cells involved in monocyte migration and inflammation. Antcin K not only reduced the expression of the CD36 scavenger receptor but also augmented the expression of Kruppel-like factor 4 (KLF4) transcription factor in macrophages, which inhibits the transformation of macrophages into foam cells underlying the pathological process of atherosclerosis. Taking our findings into account, we suggested that botanical antcin K could have therapeutic potential for the treatment of atherosclerosis.

Plant Therapeutics

Plants for therapeutics and the phytotherapy for disorders are the same thing in practice [...].

Oleuropein attenuates inflammation and regulates immune responses in a 2,4-dinitrochlorobenzene-induced atopic dermatitis mouse model

BACKGROUND

Olive (Olea europaea Linn) leaves contain a phenolic compound oleuropein (Ole) has antioxidant, anti-inflammatory, and immunomodulatory activities. However, whether Ole might be an effective treatment for atopic dermatitis (AD) remains unknown.

OBJECTIVE

This study investigated the functional role of oleuropein in a 2,4-dinitrochlorobenzene-induced AD-like mouse model, with a focus on allergic inflammation.

METHODS

We evaluated cytokine gene expression, COX-2 inflammatory protein production, and Th2 related cytokine regulation of mast cells and eosinophils that infiltrated AD-like skin lesions.

RESULTS

A topical application of Ole significantly reduced Th2-related cytokine gene expression (IL-4 and IL-5) and inflammatory COX-2 protein production in AD-like skin lesions. Additionally, Ole suppressed serum IgE levels. Furthermore, Ole effectively reduced ear swelling and epidermal and dermal thickening.

CONCLUSIONS

These results suggested that, mechanistically, Ole treatment improved allergic inflammation by blocking the Th2-driven inflammatory axis. In conclusion, our findings indicated that Ole showed promise in treating AD by regulating serum IgE and Th2 cytokine levels. Although the effects of Ole on AD in humans require clinical trials, our results provided insights into how AD treatments might be improved.

Effects of α-Lipoic Acid on Phagocytosis of Oligomeric Beta-Amyloid1–42 in BV-2 Mouse Microglial Cells

Background and objectives: This study aimed to investigate the enhancing effect of vitamin-like alpha-lipoic acid (ALA) on phagocytosis of oligomeric beta-amyloid (oAβ)_1–42 in BV-2 mouse microglial cells.

Methods: An in vitro model was established to investigate phagocytosis of oAβ_1–42 in BV-2 cells. Transmission electron microscopy images indicated that the morphology of prepared oAβ_1–42 was spherical particles. BV-2 cells treated with ALA were incubated with 5(6)-carboxyfluorescein-labeled oAβ_1–42 (FAM-oAβ_1–42) for 24 h, followed by flow cytometer analysis, western blotting, real-time quantitative PCR, and immunocytochemistry (ICC) analysis to assess the in vitro phagocytosis ability of oAβ_1–42.

Results: Alpha-lipoic acid significantly increased messenger RNA (mRNA) expression of the CD36 receptor in BV-2 cells. ICC analysis showed that ALA significantly elevated CD36 protein expression in BV-2 cells both with and without oAβ_1–42 treatment. Results from the flow cytometry analysis indicated that the CD36 receptor inhibitor significantly attenuated ALA-promoted phagocytosis of FAM-oAβ_1–42 in BV-2 cells. Moreover, ICC analysis revealed that ALA caused the translocation of peroxisome proliferator-activated receptor-γ (PPAR-γ), which is known to regulate the expression of CD36 mRNA in BV-2 cells. ALA also elevated both the mRNA and protein expression of cyclooxygenase-2 (COX-2), which is a key enzyme involved in the synthesis of 15-deoxy-^Δ12,14-prostaglandin J2 in BV-2 cells.

Conclusion: We postulated that ALA enhances oAβ_1–42 phagocytosis by upregulating the COX-2/15-deoxy-^Δ12,14-prostaglandin J2/PPAR-γ/CD36 pathway in BV-2 cells. Finally, future studies should be conducted with an in vivo study to confirm the findings.

Alleviative Effect of Alpha-Lipoic Acid on Cognitive Impairment in High-Fat Diet and Streptozotocin-Induced Type 2 Diabetic Rats

Background: The intricate relationship between type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) suggests that insulin is involved in modulating AD-related proteins. Alpha-lipoic acid (ALA) can improve insulin resistance (IR) in diabetic rats. However, the role of ALA in alleviating the cognitive decline of T2DM is not yet clear. This study examined the ameliorative effect of ALA on cognitive impairment, cerebral IR, and synaptic plasticity abnormalities in high-fat diet (HFD) plus streptozotocin (STZ) induced diabetic rats.

Methods: The HFD/STZ-induced T2DM male Wistar rats were orally administered with ALA (50, 100, or 200 mg/kg BW) once a day for 13 weeks. Abilities of cognition were measured with a passive avoidance test and Morris water maze. Specimens of blood and brain were collected for biochemical analysis after the rats were sacrificed. Western blotting was used to determine protein expressions in the hippocampus and cortex in the insulin signaling pathways, long-term potentiation (LTP), and synaptic plasticity-related protein expressions.

Results: Alpha-lipoic acid improved hyperinsulinemia and the higher levels of free fatty acids of the T2DM rats. Behavioral experiments showed that the administration of ALA improved cognitive impairment in HFD/STZ-induced T2DM rats. ALA ameliorated insulin-related pathway proteins [phosphoinositide 3-kinase (PI3K), phospho-protein kinase B (pAkt)/Akt, and insulin-degrading enzyme (IDE)] and the LTP pathway, as well as synaptic plasticity proteins (calmodulin-dependent protein kinase II, cyclic AMP response element-binding protein, and postsynaptic density protein-95) of the cerebral cortex or hippocampus in HFD/STZ-induced T2DM rats.

Conclusion: Our findings suggested that ALA may ameliorate cognition impairment via alleviating cerebral IR improvement and cerebral synaptic plasticity in diabetic rats.

Ginsenoside Rg3 ameliorates allergic airway inflammation and oxidative stress in mice

Background

Ginsenoside Rg3, isolated from Panax ginseng, has anti-inflammatory and anti-tumor activities. It is known to reduce inflammation in acute lung injury in mice, and to reduce the expression of inflammatory cytokines and COX-2 in human asthmatic airway epithelium. In this study, we attempted to determine whether ginsenoside Rg3 inhibits airway inflammation, oxidative stress, and airway hyperresponsiveness (AHR) in the lungs of asthmatic mice. We also investigated its effects on oxidative stress and the inflammatory response in tracheal epithelial cells.

Methods

Asthma symptoms were induced in female BALB/c mice sensitized with ovalbumin (OVA). Mice were divided into five groups: normal controls, OVA-induced asthmatic controls, and asthmatic mice treated with ginsenoside Rg3 or prednisolone by intraperitoneal injection. Inflammatory BEAS-2B cells (human tracheal epithelial cells) treated with ginsenoside Rg3 to investigate its effects on inflammatory cytokines and oxidative responses.

Results

Ginsenoside Rg3 treatment significantly reduced eosinophil infiltration, oxidative responses, airway inflammation, and AHR in the lungs of asthmatic mice. Ginsenoside Rg3 reduced Th2 cytokine and chemokine levels in bronchoalveolar lavage fluids and lung. Inflammatory BEAS-2B cells treated with ginsenoside Rg3 reduced the eotaxin and pro-inflammatory cytokine expressions, and monocyte adherence to BEAS-2B cells was significantly reduced as a result of decreased ICAM-1 expression. Furthermore, ginsenoside Rg3 reduced the expression of reactive oxygen species in inflammatory BEAS-2B cells.

Conclusion

Ginsenoside Rg3 is a potential immunomodulator that can ameliorate pathological features of asthma by decreasing oxidative stress and inflammation

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Ginsenoside Rg3 reduced eosinophil infiltration, and airway hyperresponsiveness in the lungs of asthmatic mice.

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Ginsenoside Rg3 inhibited oxidative responses in the lungs.

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Ginsenoside Rg3 reduced the levels of Th2 cytokines in BALF and lung.

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Ginsenoside Rg3 inhibited monocyte cell adherence to tracheal epithelial cells.

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Ginsenoside Rg3 reduced the levels of pro-inflammatory cytokines in tracheal epithelial cells.

Vescalagin from Pink Wax Apple (Syzygium samarangense (Blume) Merrill and Perry) Protects Pancreatic β-Cells against Methylglyoxal-Induced Inflammation in Rats

Methylglyoxal (MG) is the primary precursor of advanced glycation end products involved in the pathogenesis of inflammation and diabetes. A previous study in our laboratory found anti-inflammatory and anti-hyperglycemic effects of the polyphenol vescalagin (VES) in rats with MG-induced carbohydrate metabolic disorder. The present study further investigated the occurrence of inflammation in pancreatic β-cells in MG-induced diabetic rats and the mechanism by which VES prevents it. The results showed that VES downregulates the protein expression levels of advanced glycation end product receptors and CCAAT/enhancer binding protein-β and upregulates the protein expression levels of pancreatic duodenal homeobox-1, nuclear factor erythroid 2-related factor 2 and glyoxalase I from the pancreatic cells. The results also revealed that VES elevates glutathione and antioxidant enzyme contents and then downregulates c-Jun N-terminal kinase and p38 mitogen-activated protein kinases pathways to protect pancreatic β-cells in MG-administered rats.

Alleviative Effect of Ruellia tuberosa L. on Insulin Resistance and Abnormal Lipid Accumulation in TNF-α-Treated FL83B Mouse Hepatocytes

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease, and most patients with T2DM develop nonalcoholic fatty liver disease (NAFLD). Both diseases are closely linked to insulin resistance (IR). Our previous studies demonstrated that Ruellia tuberosa L. (RTL) extract significantly enhanced glucose uptake in the skeletal muscles and ameliorated hyperglycemia and IR in T2DM rats. We proposed that RTL might be via enhancing hepatic antioxidant capacity. However, the potent RTL bioactivity remains unidentified. In this study, we investigated the effects of RTL on glucose uptake, IR, and lipid accumulation in vitro to mimic the T2DM accompanied by the NAFLD paradigm. FL83B mouse hepatocytes were treated with tumor necrosis factor-α (TNF-α) to induce IR, coincubated with oleic acid (OA) to induce lipid accumulation, and then, treated with RTL fractions, fractionated with n-hexane or ethyl acetate (EA), from column chromatography, and analyzed by thin-layer chromatography. Our results showed that the ethyl acetate fraction (EAf2) from RTL significantly increased glucose uptake and suppressed lipid accumulation in TNF-α plus OA-treated FL83B cells. Western blot analysis showed that EAf2 from RTL ameliorated IR by upregulating the expression of insulin-signaling-related proteins, including protein kinase B, glucose transporter-2, and peroxisome proliferator-activated receptor alpha in TNF-α plus OA-treated FL83B cells. The results of this study suggest that EAf2 from RTL may improve hepatic glucose uptake and alleviate lipid accumulation by ameliorating and suppressing the hepatic insulin signaling and lipogenesis pathways, respectively, in hepatocytes.

Tomatidine ameliorates obesity-induced nonalcoholic fatty liver disease in mice

Tomatidine is isolated from the leaves and green fruits of some plants in the Solanaceae family, and has been reported to have anti-inflammatory and antitumor effects. Previous studies have found that tomatidine decreases hepatic lipid accumulation via regulation of vitamin D receptor and activation of AMP-activated protein kinase (AMPK) phosphorylation. However, whether tomatidine reduces weight gain and improves nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, we investigated how tomatidine ameliorates NAFLD in obese mice and evaluated the regulatory mechanism of lipogenesis in hepatocytes. Male C57BL/6 mice were fed a high-fat diet (HFD) to induce obesity and NAFLD, and treated with tomatidine via intraperitoneal injection. In vitro, FL83B hepatocytes were incubated with oleic acid and treated with tomatidine to evaluate lipid metabolism. Our results demonstrate that tomatidine significantly decreases body weight and fat weight compared to HFD-fed mice. In addition, tomatidine decreased hepatic lipid accumulation and improved hepatocyte steatosis in HFD-induced obese mice. We also found that tomatidine significantly regulated serum total cholesterol, fasting blood glucose, low-density lipoprotein, and triglyceride levels, but the serum high-density lipoprotein and adiponectin concentrations were higher than in the HFD-fed obese mice. In vivo and in vitro, tomatidine significantly suppressed the expression of fatty acid synthase and transcription factors involved in lipogenesis, and increased the expression of adipose triglyceride lipase. Tomatidine promoted the sirtuin 1 (sirt1)/AMPK signaling pathway to increase lipolysis and β-oxidation in fatty liver cells. These findings suggest that tomatidine potentially ameliorates obesity and acts against hepatic steatosis by regulating lipogenesis and the sirt1/AMPK pathway.

Identification of Bioactive Components from Ruellia tuberosa L. on Improving Glucose Uptake in TNF-α-Induced Insulin-Resistant Mouse FL83B Hepatocytes

Ruellia tuberosa L. (RTL) has been used as a folk medicine to cure diabetes in Asia. RTL was previously reported to alleviate hyperglycemia, insulin resistance (IR), abnormal hepatic detoxification, and liver steatosis. However, the potential bioactive compounds of RTL have still not been identified. The aim of this study was to investigate the bioactive compounds in RTL ethyl acetate (EA) fractions by using a glucose uptake assay in TNF-α-treated mouse FL83B hepatocytes to discover a mechanism by which to improve IR. The bioactive compounds were identified by the high-performance liquid chromatography (HPLC) assay. Using the Sephadex LH20 gel packing chromatography column, the EAF5 fraction was isolated from RTL and significantly increased glucose uptake in TNF-α-treated FL83B cells. Moreover, the MCI gel packing chromatography column separated EAF5 into five subfractions and had no significant cytotoxic effect in FL83B cells when treated at the concentration of 25 μg/ml. Among the subfractions, EAF5-5 markedly enhanced glucose uptake in TNF-α-treated FL83B cells. The possible bioactive compounds of the EAF5-5 fraction that were identified by the HPLC assay include syringic acid, p-coumaric acid, and cirsimaritin. The bioactive compound with the best effect of increasing glucose uptake was p-coumaric acid, but its effect alone was not as good as the combined effect of all three compounds of the EAF5-5 fraction. Thus, we speculate that the antidiabetic effect of RTL may be the result of multiple active ingredients.

Phloretin ameliorates hepatic steatosis through regulation of lipogenesis and Sirt1/AMPK signaling in obese mice

Background

Phloretin is isolated from apple trees and could increase lipolysis in 3T3-L1 adipocytes. Previous studies have found that phloretin could prevent obesity in mice. In this study, we investigated whether phloretin ameliorates non-alcoholic fatty liver disease (NAFLD) in high-fat diet (HFD)-induced obese mice, and evaluated the regulation of lipid metabolism in hepatocytes.

Methods

HepG2 cells were treated with 0.5 mM oleic acid to induce lipid accumulation, and then treated with phloretin to evaluate the molecular mechanism of lipogenesis. In another experiment, male C57BL/6 mice were fed normal diet or HFD (60% fat, w/w) for 16 weeks. After the fourth week, mice were treated with or without phloretin by intraperitoneal injection for 12 weeks.

Results

Phloretin significantly reduced excessive lipid accumulation and decreased sterol regulatory element-binding protein 1c, blocking the expression of fatty acid synthase in oleic acid-induced HepG2 cells. Phloretin increased Sirt1, and phosphorylation of AMP activated protein kinase to suppress acetyl-CoA carboxylase expression, reducing fatty acid synthesis in hepatocytes. Phloretin also reduced body weight and fat weight compared to untreated HFD-fed mice. Phloretin also reduced liver weight and liver lipid accumulation and improved hepatocyte steatosis in obese mice. In liver tissue from obese mice, phloretin suppressed transcription factors of lipogenesis and fatty acid synthase, and increased lipolysis and fatty acid β-oxidation. Furthermore, phloretin regulated serum leptin, adiponectin, triglyceride, low-density lipoprotein, and free fatty acid levels in obese mice.

Conclusions

These findings suggest that phloretin improves hepatic steatosis by regulating lipogenesis and the Sirt-1/AMPK pathway in the liver.

Effects of Maillard reaction products in a glucose-glycine alcoholic solution on antioxidative and antimutagenic activities

BACKGROUND

Marinating meat with alcohol, such as wine and beer, is a common culinary practice in cultures worldwide. In this study we use a model marination solution comprising 0.2  mol L^-1 glucose-0.2  mol L^-1 glycine buffered to pH 4.3 containing either 0 or 50% ethanol and mimicked the cooking process by heating for 12 h. Antioxidative and antimutagenic characteristics of Maillard reaction products (MRPs) were investigated. Reducing power, antioxidant activity (ferrous ion chelating ability), and free radical neutralization ability generated from 1,1-diphenyl-2-pichrylhydrazyl and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) were determined. Ames testing was performed.

RESULTS

Results indicate that MRPs from aqueous and alcoholic solution exhibit four antioxidative assays in a dose-dependent manner from 0.16 to 10.00 mg mL^-1 . However, MRPs from the alcoholic model were superior. In Ames testing, MRPs from both models are neither toxic nor mutagenic at the test concentrations of 0.63-10.00 mg/plate. However, MRPs from the alcoholic model exhibited a higher inhibitory effect on the direct-acting mutagen 4-nitroquinoline-N-oxide compared with the aqueous model. This result is consistent with the observation that MRPs with higher antioxidative capacity exhibit superior antimutagenic activity, suggesting that there are more different products in the alcoholic model.

CONCLUSION

Our results add to the current knowledge about the antioxidative and antimutagenic properties of MRPs arising when food is cooked in the presence of ethanol. © 2018 Society of Chemical Industry.

Protective effect of Ruellia tuberosa L. extracts against abnormal expression of hepatic detoxification enzymes in diabetic rats

Ruellia tuberosa L. (RTL) has been used as a folk medicine for curing diabetes mellitus in East Asia decades. This study investigated the effect of RTL on hepatic detoxification enzyme expression in diabetic rats. Male Wistar rats were fed a high fat diet (HFD) and intraperitoneally injected with streptozotocin (STZ) to induce diabetes. Subsequently, rats received oral administrations of 100 or 400 mg kg⁻¹ body weight RTL extract, in either water (RTLW) or ethanol (RTLE), once a day for 4 weeks. The real-time PCR analyses showed that abnormality of hepatic phase I and II detoxification enzyme expression was observed in diabetic rats. However, both RTLW and RTLE significantly normalized the expression of hepatic phase I detoxification enzymes such as CYP 2E1, and expression of phase II detoxification enzymes such as UGT 1A7 and GST M1 in diabetic rats. Furthermore, we found that fasting serum glucose, hemoglobin A1C (HbA1C) and the area under the curve of oral glucose tolerance test (AUC_OGTT) levels were significantly reduced in both RTLW and RTLE treated diabetic rats. Moreover, both RTLW and RTLE significantly increased the activity of hepatic anti-oxidative enzymes such as superoxide dismutase (SOD) in diabetic rats. The present study suggests that RTL may ameliorate abnormal hepatic detoxification function via alleviating hyperglycemia and enhancing hepatic antioxidant capacity in HFD/STZ-induced diabetic rats.

Ruellia tuberosa L. (RTL) has been used as a folk medicine for curing diabetes mellitus in East Asia decades.

Vescalagin from Pink Wax Apple [Syzygium samarangense (Blume) Merrill and Perry] Alleviates Hepatic Insulin Resistance and Ameliorates Glycemic Metabolism Abnormality in Rats Fed a High-Fructose Diet

This study investigates the ameliorative effect of vescalagin (VES) isolated from Pink wax apple fruit on hepatic insulin resistance and abnormal carbohydrate metabolism in high-fructose diet (HFD)-induced hyperglycemic rats. The results show that in HFD rats, VES significantly reduced the values of the area under the curve for glucose in an oral glucose tolerance test and the homeostasis model assessment of insulin resistance index. VES significantly enhanced the activity of hepatic antioxidant enzymes while reducing thiobarbituric acid-reactive substances in HFD rats. Western blot assay revealed that VES reduced hepatic protein expression involved in inflammation pathways while up-regulating expression of hepatic insulin signaling-related proteins. Moreover, VES up-regulated the expression of hepatic glycogen synthase and hepatic glycolysis-related proteins while down-regulating hepatic gluconeogenesis-related proteins in HFD rats. This study suggests some therapeutic potential of VES in preventing the progression of diabetes mellitus.

Design a light pattern of multiple concentric circles for LED fishing lamps using Fourier series and an energy mapping method

Fourier series and an energy mapping method were used in this study to design a lens that produces a light pattern of multiple concentric circles (LPMCC) for a light-emitting diode (LED) fishing lamp. Fourier series were used to represent the light intensity distribution curve (LIDC) of the LPMCC light pattern. Energy mapping involves performing angular energy mapping based on the LIDCs of an LED light source and LPMCC to design a freeform lens. Type I and Type II LPMCC lenses were designed according to the phototaxis behavior of fish to create a LPMCC light pattern of interleaving light-dark zones that attracts fish shoals to stay in an area for a long period. The experimental results indicated that, in comparing the LIDCs of the Type I and II lenses with the respective simulation values, the normalized cross-correlation (NCC) value reached 96%. According to a 24-hour observation of the phototaxis of Poecilia reticulata to evaluate the effectiveness of the proposed light pattern to attract fish, when a fish shoal was habituated to a light source that emitted constant illumination light, it gradually moved away from the intense light zone and hovered around the junction of the light and dark zones. In the future, the design used in this study can be applied to LED fishing lamps to replace traditional fishing lamps.

Design and testing of a uniformly solar energy TIR-R concentration lenses for HCPV systems

In this paper, total internal reflection-refraction (TIR-R) concentration (U-TIR-R-C) lens module were designed for uniformity using the energy configuration method to eliminate hot spots on the surface of solar cell and increase conversion efficiency. The design of most current solar concentrators emphasizes the high-power concentration of solar energy, however neglects the conversion inefficiency resulting from hot spots generated by uneven distributions of solar energy concentrated on solar cells. The energy configuration method proposed in this study employs the concept of ray tracing to uniformly distribute solar energy to solar cells through a U-TIR-R-C lens module. The U-TIR-R-C lens module adopted in this study possessed a 76-mm diameter, a 41-mm thickness, concentration ratio of 1134 Suns, 82.6% optical efficiency, and 94.7% uniformity. The experiments demonstrated that the U-TIR-R-C lens module reduced the core temperature of the solar cell from 108 °C to 69 °C and the overall temperature difference from 45 °C to 10 °C, and effectively relative increased the conversion efficiency by approximately 3.8%. Therefore, the U-TIR-R-C lens module designed can effectively concentrate a large area of sunlight onto a small solar cell, and the concentrated solar energy can be evenly distributed in the solar cell to achieve uniform irradiance and effectively eliminate hot spots.

Protective effects of vescalagin from pink wax apple [Syzygium samarangense (Blume) Merrill and Perry] fruit against methylglyoxal-induced inflammation and carbohydrate metabolic disorder in rats

The unbalance of glucose metabolism in humans may cause the excessive formation of methylglyoxal (MG), which can react with various biomolecules to form the precursor of advanced glycation end products (AGEs). Vescalagin (VES) is an ellagitannin that alleviates insulin resistance in cell study. Results showed that VES reduced the value of oral glucose tolerance test, cardiovascular risk index, AGEs, and tumor necrosis factor-α contents while increasing C-peptide and d-lactate contents significantly in rats orally administered MG and VES together. The preventive effect of VES on MG-induced inflammation and carbohydrate metabolic disorder in rats was thus proved. On the basis of the experiment data, a mechanism, which involves the increase in d-lactate to retard AGE formation and the decrease in cytokine release to prevent β-cell damage, is proposed to explain the bioactivities of VES in antiglycation and in the alleviation of MG-induced carbohydrate metabolic disorder in rats.

An extract from wax apple (Syzygium samarangense (Blume) Merrill and Perry) effects glycogenesis and glycolysis pathways in tumor necrosis factor-α-treated FL83B mouse hepatocytes

FL83B mouse hepatocytes were treated with tumor necrosis factor-α (TNF-α) to induce insulin resistance to investigate the effect of a wax apple aqueous extract (WAE) in insulin-resistant mouse hepatocytes. The uptake of 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2 NBDG), a fluorescent D-glucose derivative, was performed, and the metabolism of carbohydrates was evaluated by examining the expression of glycogenesis or glycolysis-related proteins in insulin-resistant hepatocytes. The results show that WAE significantly improves the uptake of glucose and enhances glycogen content in insulin-resistant FL83B mouse hepatocytes. The results from Western blot analysis also reveal that WAE increases the expression of glycogen synthase (GS), hexokinase (HXK), glucose-6-phosphate dehydrogenase (G6PD), phosphofructokinase (PFK) and aldolase in TNF-α treated cells, indicating that WAE may ameliorate glucose metabolism by promoting glycogen synthesis and the glycolysis pathways in insulin-resistant FL83B mouse hepatocytes.

Hypotriglyceridemic and hypoglycemic effects of vescalagin from Pink wax apple [Syzygium samarangense (Blume) Merrill and Perry cv. Pink] in high-fructose diet-induced diabetic rats

Vescalagin, an active component from Pink wax apple [Syzygium samarangense (Blume) Merrill and Perry cv. Pink] fruit, with glucose uptake enhancing ability in insulin-resistant FL83B mouse hepatocytes, as shown in our previous study, was further evaluated for its hypotriglyceridemic and hypoglycemic effects in high-fructose diet (HFD)-induced diabetic rats. Wistar rats were fed HFD for 16 weeks and orally administered with vescalagin from Pink wax apple daily during the last 4 weeks. The results of biochemical parameters showed that fasting blood glucose, C-peptide, fructosamine, triglyceride and free fatty acid contents decreased by 44.7%, 46.2%, 4.0%, 42.5%, and 10.8%, respectively, in the HFD-induced diabetic rats administered with vescalagin at 30 mg/kg body weight in comparison with those of control HFD-induced diabetic rats. However, high-density-lipoprotein-cholesterol content increased by 14.4% in the HFD rats treated with vescalagin. The present study reveals that vescalagin could have therapeutic value against diabetic progression via its anti-hypertriglyceridemic and anti-hyperglycemic effects.

Spin-resolved Purcell effect in a quantum dot microcavity system

We demonstrate the spin selective coupling of the exciton state with cavity mode in a single quantum dot (QD)-micropillar cavity system. By tuning an external magnetic field, each spin polarized exciton state can be selectively coupled with the cavity mode due to the Zeeman effect. A significant enhancement of spontaneous emission rate of each spin state is achieved, giving rise to a tunable circular polarization degree from -90% to 93%. A four-level rate equation model is developed, and it agrees well with our experimental data. In addition, the coupling between photon mode and each exciton spin state is also achieved by varying temperature, demonstrating the full manipulation over the spin states in the QD-cavity system. Our results pave the way for the realization of future quantum light sources and the quantum information processing applications.

Fraction from wax apple [Syzygium samarangense (Blume) Merrill and Perry] fruit extract ameliorates insulin resistance via modulating insulin signaling and inflammation pathway in tumor necrosis factor α-treated FL83B mouse hepatocytes

Inflammation is associated with the development of insulin resistance in Type 2 diabetes mellitus. In the present study, mouse FL83B cells were treated with tumor necrosis factor-alpha (TNF-α) to induce insulin resistance, and then co-incubated with a fraction from wax apple fruit extract (FWFE). This fraction significantly increased the uptake of the nonradioactive fluorescent indicator 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-d-glucose (2-NBDG) in insulin resistant cells. Western blot analysis revealed that, compared with the TNF-α-treated control group, FWFE increased the expression of the insulin receptor (IR), insulin receptor substrate-1 (IRS-1), protein kinase B (Akt/PKB), phosphatidylinositol-3 kinase (PI3K), and glucose transporter 2 (GLUT-2), and increased IR tyrosyl phosporylation, in insulin resistant FL83B cells. However, FWFE decreased phosphorylation of c-Jun N-terminal kinases (JNK), but not the expression of the intercellular signal-regulated kinases (ERK), in the same cells. These results suggest that FWFE might alleviate insulin resistance in TNF-α-treated FL83B cells by activating PI3K-Akt/PKB signaling and inhibiting inflammatory response via suppression of JNK, rather than ERK, activation.

Effect of water extracts from edible Myrtaceae plants on uptake of 2-(n-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose in TNF-α-treated FL83B mouse hepatocytes

This study investigated the glucose uptake activity of the water extracts from the leaves and fruit of edible Myrtaceae plants, including guava (Psidium guajava Linn.), wax apples [Syzygium samarangense (Blume) Merr. and L.M. Perry], Pu-Tau [Syzygium jambo (L.) Alston], and Kan-Shi Pu-Tau (Syzygium cumini Linn.) in FL83B mouse hepatocytes. The fluorescent dye 2-(n-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose was used to estimate the uptake ability of the cells. Glucose uptake test showed that pink wax apple fruit extract (PWFE) exhibits the highest glucose uptake activity, at an increment of 21% in the insulin-resistant FL83B mouse hepatocytes as compared with the TNF-α-treated control group. Vescalagin was isolated using column chromatography of PWFE. This compound, at the concentration of 6.25 µg/mL, exhibits the same glucose uptake improvement in insulin-resistant cells as PWFE at a 100-µg/mL dose. We postulate that vescalagin is an active component in PWFE that may alleviate the insulin resistance in mouse hepatocytes.

Browning in ethanolic solutions of ascorbic acid and catechin

Nonenzymatic browning occurs readily in alcoholic beverages and degrades their color quality. Ascorbic acid degradation in the presence of phenolic compounds is a major browning pathway in alcoholic beverages with fruit or fruit juice as the raw material or an ingredient. In the present study ethanolic solutions of ascorbic acid and catechin were prepared to simulate the alcoholic beverages. Ascorbic acid degradation and browning in these model solutions were investigated. Glycerol solutions with the same water activity (A(w)) values as those of the ethanolic model solutions were used as controls in the evaluation of browning rate. Results showed that the aerobic degradation of ascorbic acid dominates over the anaerobic one in ethanolic solutions, that the browning rate decreases as the ethanol concentration increases, that the compound 3-hydroxy-2-pyrone may not be a good indicator of browning in ethanolic ascorbic acid-catechin solutions, and that A(w) is a major factor responsible for the difference in the browning rate among ascorbic acid-catechin solutions with different ethanol concentrations.

Color loss in ethanolic solutions of chlorophyll a

The present study investigated the stability of green color in 1-60% ethanolic solutions of chlorophyll a. Kinetics studies were performed. The results show that the color loss follows first-order reaction kinetics, similar to that in aqueous systems, with a reaction rate constant between 0.013 and 13.575 day(-1) at 20 degrees C and an activation energy between 18.4 and 85.1 kJ mol(-1). The rate of color loss increases with the temperature and varies with the ethanol concentration. It reaches the maximum at 40% ethanol concentrations. The difference among the absorption spectra of the ethanolic solutions suggests that the interaction between water and ethanol molecules may be the major factor affecting the color stability of chlorophyll in the solutions. The bathochromic shift is most obvious around 40% ethanol concentration. We postulate that the formation of clusters of water-ethanol molecules is responsible for the increase in the rate of color loss.

Magnetic field control of the quantum chaotic dynamics of hydrogen analogs in an anisotropic crystal field

We report magnetic field control of the quantum chaotic dynamics of hydrogen analogues in an anisotropic solid state environment. The chaoticity of the system dynamics was quantified by means of energy level statistics. We analyzed the magnetic field dependence of the statistical distribution of the impurity energy levels and found a smooth transition between the Poisson limit and the Wigner limit, i.e., transition between regular Poisson and fully chaotic Wigner dynamics. The effect of the crystal field anisotropy on the quantum chaotic dynamics, which manifests itself in characteristic transitions between regularity and chaos for different field orientations, was demonstrated.

STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : III. CHANGES IN THESE PROPERTIES OF MYOSIN SOLUTIONS IN RELATION TO ADENOSINETRIPHOSPHATE AND MUSCULAR CONTRACTION

1. An investigation of the physicochemical properties of myosin has been carried out. Prepared under standard conditions, the ratio of flow-birefringence to protein concentration is uniform. The effect of electrolytes, pH, and urea on the flow-birefringence and viscosity (relative and anomalous) of myosin has been examined. 2. Decrease or abolition of flow-birefringence does not necessarily imply far reaching denaturation, since such effects can be reversed by a variety of means. 3. When a myosin solution is treated with adenosinetriphosphate, its flow-birefringence is decreased (average 48 per cent), its anomalous viscosity is retained, and its relative viscosity is decreased (average 14 per cent). The full effect of adenosinetriphosphate is obtained at 0.004 M; a molarity very much less than that of other substances which decrease the flow-birefringence of myosin. 4. The changes in the physicochemical properties of myosin brought about by adenosinetriphosphate are spontaneously reversible, and are connected with the enzymatic action of the protein as adenosinetriphosphatase. 5. Effects similar to those of adenosinetriphosphate on the physicochemical properties of purified myosin have been obtained so far only with inosinetriphosphate. 6. Inorganic phosphate is split off by myosin from inosinetriphosphate as well as from adenosinetriphosphate. Inorganic triphosphate is split by 1 to 2 per cent solution of three times precipitated myosin. 7. Adenosinediphosphate and inorganic triphosphate act as competitive inhibitors with adenosinetriphosphate, blocking the fall of flow-birefringence. 8. The implications of the results, and the conception of active enzymic groups attached to proteins participating in cell structure, whether contractile or non-contractile, are discussed in relation to present views on muscle physiology and other biological problems.

STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : II. ON DILUTE SOLUTIONS OF PROTEINS FROM EMBRYONIC AND OTHER TISSUES

1. An extensive investigation has been made of protein particle shape using the methods of flow-birefringence and anomalous viscosity measurement in the coaxial cell. 2. As a result of investigations on a number of proteins, it is concluded that they may be divided into four groups. Group A consists of those which show flow-anomaly both in the bulk phase and in the surface film. These also show flow-birefringence in the bulk phase. Examples: tobacco mosaic disease virus nucleoprotein; myosin. Though corpuscular proteins, they have elongated particles before denaturation. Group B consists of those which show flow-anomaly only (in the first instance) in the surface film, and no flow-birefringence in the bulk phase. They are probably close to spherical in shape in solution, but form elongated particles as they denature in the surface film. After this process has been completed, they may show flow-anomaly also in the bulk phase. Some proteins show flow-anomaly in the surface film immediately it forms, others only show it after a certain time has elapsed for the building up of the film. We designate the former as group B₁ and the latter as group B₂. Group B₁, immediate surface film flow-anomaly. Examples: serum euglobulin, amphibian embryo euglobulin b. Group B₂, slowly appearing surface film flow-anomaly. After the film has once been fully formed and then dispersed by shaking, the solution may have the properties of that of a protein in group B₁; i.e., anomalous flow in the film may occur immediately on testing in the viscosimeter. Examples: avian ovalbumin, amphibian embryo pseudoglobulin. Group C consists of those proteins which show flow-anomaly neither in the bulk phase nor in the surface film, under the conditions used by us. They are probably close to spherical in shape. Examples: insulin, methaemoglobin, amphibian embryo euglobulin c, mucoproteins. 3. The theoretical significance of protein fibre molecules, whether native or formed by denaturation in the living cell, is discussed, especially in relation to experimental morphology and cytology.

STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS : I. GENERAL BEHAVIOUR OF PROTEINS SUBJECTED TO SHEAR

1. A coaxial viscosimeter which permits the simultaneous determination of relative and anomalous viscosity and of flow-birefringence is described. Flow-anomaly and flow-birefringence are regarded as characteristic of elongated micelles and molecules. 2. Such methods have been applied to dilute solutions of proteins. The conditions under which the coaxial (Couette) viscosimeter measures the viscosity of the bulk phase and the surface film phase respectively have been investigated and are described. 3. The general behaviour of protein solutions subjected to shear is summarised.

Effect of guava (Psidium guajava L.) leaf extract on glucose uptake in rat hepatocytes

People in oriental countries, including Japan and Taiwan, boil guava leaves (Psidium guajava L.) in water and drink the extract as a folk medicine for diabetes. The present study investigated the enhancement of aqueous guava leaf extract on glucose uptake in rat clone 9 hepatocytes and searched for the active compound. The extract was eluted with MeOH-H(2)O solutions through Diaion, Sephadex, and MCI-gel columns to separate into fractions with different polarities. The uptake test of 2-[1-(14)C] deoxy-D-glucose in rat clone 9 hepatocytes was performed to evaluate the hypoglycemic effect of these fractions. The active compound was identified by nuclear magnetic resonance analysis and high-performance liquid chromatography (HPLC). The results revealed that phenolics are the principal component of the extract, that high polarity fractions of the guava leaf extract are enhancers to glucose uptake in rat clone 9 hepatocytes, and that quercetin is the major active compound. We suggest that quercetin in the aqueous extract of guava leaves promotes glucose uptake in liver cells, and contributes to the alleviation of hypoglycemia in diabetes as a consequence.

Effects of caffeic acid and cinnamic acid on glucose uptake in insulin-resistant mouse hepatocytes

Tumor necrosis factor-alpha was used to induce insulin resistance of mouse liver FL83B cells. Two phenolic acids, caffeic acid and cinnamic acid, were then added separately to investigate their effects on glucose uptake of the insulin-resistant cells. The results suggest that these two phenolic acids may promote insulin receptor tyrosyl phosphorylation, up-regulate the expression of insulin signal associated proteins, including insulin receptor, phosphatidylinositol-3 kinase, glycogen synthase, and glucose transporter-2, increase the uptake of glucose, and alleviate insulin resistance in cells as a consequence.

Rapid fabrication of a micro-ball lens array by extrusion for optical fiber applications

Batch-fabrication of a micro-ball lens array (MBA) could not only reduce micro assembly costs but also replace conventional ball lenses or costly GRINs (Gradient Refractive Index) without compromising performance. Compared with conventional half-spherical micro-lenses, the MBA is a spherical micro-lens that can focus light in all directions, thus providing the flexibility required for optical applications. Current MBAs are made of SU-8 photoresist by an extrusion process rather than the traditional thermal reflow process. The aim of this study was to develop a new process for MBA batch-fabrication, performed at ambient temperature, by spin-coating SU-8 onto a silicon-wafer surface, which serves as an extrusion plate, and extruding it through a nozzle to form an MBA. The nozzle consists of a nozzle orifice and nozzle cavity, the former being defined and made from SU-8 photoresist using ultra-violet (UV) lithography, which results in good mechanical properties. In this paper, the fabrication of 4 x 4 MBAs with diameters ranging from 60 to 550 um is described. Optical measurements indicated a diameter variance within 3% and a maximum coupling efficiency of approximately 62% when the single mode fiber (SMF) was placed at a distance of 10 um from the MBA. The results of this study proved that MBA fabrication by the extrusion process can enhance the coupling efficiency.

Realization of anisotropic diamagnetic kepler problem in a solid state environment

The anisotropic diamagnetic Kepler problem (ADKP) is realized experimentally by the orbital electrons of a P donor in Si under magnetic fields. The interference of electron wave packets which leads to quasi-Landau resonances (QLR) were observed. Applying the closed-orbit theory to an anisotropic solid state environment, we have identified orbits responsible for the QLR manifesting the quantum chaotic behavior in Rydberg atoms. The excellent consistency between the measured spectra and theoretical calculation provides unambiguous evidence of quantum chaotic dynamics of electrons in the ADKP.

Growth inhibition and induction of apoptosis in U937 cells by Coptis chinensis extract

Dried Coptidis Rizoma was extracted with boiling water. Conditioned medium was prepared by stimulating human peripheral blood mononuclear cells with Coptidis Rizoma extract (CR). The conditioned medium was then added to human leukemic U937 cells suspension for investigating the antiproliferation effect and the induction of apoptosis. Apparent DNA fragmentation and morphological changes occurred in U937 cells after incubating for 48 h to 72 h with the conditioned medium that had been prepared with 400 microg CR solids/mL. Flow cytometric analysis revealed that the percentage of apoptotic U937 cells increased in a time- and concentration-dependent manner. The upregulation of Bax expression, the downregulation of Bcl-2 and procaspase-3 expression, and the release of cytochrome c from the mitochondria in U937 cells were all observed. Reverse transcription-polymerase chain reaction detected cytokine-related mRNA expressions in human mononuclear cells incubated with CR. An increase in the concentration of CR in culturing medium downregulated granulocyte macrophage colony-stimulatory factor mRNA expression while upregulated interleuken-2 mRNA expression. All the above-mentioned evidences suggest that CR induces the apoptosis of human leukemic U937 cells via the changes in cytokine profile and protein expressions in mitochondria pathway and that CR has the potential to be used in the therapy of leukemia due to its strong apoptosis-promoting effect.

Solid-phase low temperature steam-assisted synthesis of thermal stable alumina nanowires

A simple steam-assisted solid phase synthesis method was developed for synthesis of boehmite nanowires in the presence of TEAOH surfactant. The boehmite nanowires had uniform diameters (12-16 nm) and length up to 1-2 microm. The morphology of the nanostructured wires was well preserved after being converted to pure gamma-Al2O3 by thermal treatment at 600 degrees C for 5 h. The nanowires of Al2O3 exhibited excellent thermal stability by retarding the phase transformation and maintaining the wires-like nanostructure after being aged up to 1300 degrees C by preventing sintering between particles at high temperatures. The surface areas of Al2O3 nanowires could be maintained as high as 68 m2/g at 1300 degrees C while the surface areas of Al2O3 micropowder shrank to 0.89 m2/g after same thermal treatment. Both in-situ XRD and 27Al NMR results indicated that the crystal structure of gamma-Al2O3 nanowires was not transformed to alpha-Al2O3 at 1300 degrees C whereas micropowder Al2O3 was fully converted to alpha-Al2O3 at 1100 degrees C.