The effects of naringenin and naringin on the glucose uptake and AMPK phosphorylation in high glucose treated HepG2 cells

BackgroundNaringin and its aglycone naringenin are citrus-derived flavonoids with several pharmacological effects. On the other hand, the mechanism for the anti-diabetic effects of naringenin and naringin are controversial and remain to be clarified further.ObjectiveThis study examined the relationship between glucose uptake and AMP-activated protein kinase (AMPK) phosphorylation by naringenin and naringin in high glucose-treated HepG2 cells.MethodsGlucose uptake was measured using the 2-NBDG fluorescent D-glucose analog. The phosphorylation levels of AMPK and GSK3β (Glycogen synthase kinase 3 beta) were observed by Western blotting. Molecular docking analysis was performed to evaluate the binding affinity of naringenin and naringin to the γ-subunit of AMPK.ResultsThe treatment with naringenin and naringin stimulated glucose uptake regardless of insulin stimulation in high glucose-treated HepG2 cells. Both flavonoids increased glucose uptake by promoting the phosphorylation of AMPK at Thr172 and increased the phosphorylation of GSK3β. Molecular docking analysis showed that both naringenin and naringin bind to the γ-subunit of AMPK with high binding affinities. In particular, naringin showed higher binding affinity than the true modulator, AMP with all three CBS domains (CBS1, 3, and 4) in the γ-subunit of AMPK. Therefore, both naringenin and naringin could be positive modulators of AMPK activation, which enhance glucose uptake regardless of insulin stimulation in high glucose-treated HepG2 cells.ConclusionsThe increased phosphorylation of AMPK at Thr172 by naringenin and naringin might enhance glucose uptake regardless of insulin stimulation in high glucose treated HepG2 cells.     

A new tray-type arena to mass rear Neoseiulus baraki, a predatory mite of coconut mite, Aceria guerreronis in the laboratory

Neoseiulus baraki Athias-Henriot (Acari: Phytoseiidae) is an important predatory mite of the coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae) and attempts are now being made to evaluate the effectiveness of augmenting N. baraki to control coconut mite in the field. These studies require a steady supply of N. baraki in large numbers. One major constraint of the existing method to mass rear N. baraki on Tyrophagus putrescentiae Shrank (Acari: Acaridae) in a closed arena without a water barrier was frequent contamination of cultures by other mites. This paper describes the development of an efficient method to mass rear N. baraki in the laboratory with less monitoring and relatively minimal contaminants. Three box-type arenas and a tray-type arena were tested to mass rear T. putrescentiae. Mites were successfully developed on two box-type arenas and the tray-type arena, but the production (2197 mites per tray in 4 weeks) of T. putrescentiae was significantly higher on the tray-type arena. A 110-fold increase of T. putrescentiae was achieved in tray-type arenas in 4 weeks. None of the box-type arenas could be maintained more than 5 weeks without acarine and fungal contaminations. N. baraki could be successfully reared on the tray-type arena at least for 6 weeks. More than 4800 mites per tray, a 240-fold increase was achieved in 5 weeks when T. putrescentiae was added at 3-week intervals. Advantages and disadvantages of the new method are described.     

Good Practices in Sponge Natural Product Studies: Revising Vouchers with Isomalabaricane Triterpenes

Species misidentification in the field of natural products is an acknowledged problem. These errors are especially widespread in sponge studies, albeit rarely assessed and documented. As a case study, we aim to revisit reports of isomalabaricane triterpenes, isolated from four demosponge genera: Jaspis, Geodia, Stelletta and Rhabdastrella. From a total of 44 articles (1981–2022), 27 unique vouchers were listed, 21 of which were accessed and re-examined here: 11 (52.4%) of these were misidentified. Overall, 65.9% of the studies published an incorrect species name: previously identified Jaspis and Stelletta species were all in fact Rhabdastrella globostellata. We conclude that isomalabaricane triterpenes were isolated from only two Rhabdastrella species and possibly one Geodia species. In addition to shedding a new light on the distribution of isomalabaricane triterpenes, this study is an opportunity to highlight the crucial importance of vouchers in natural product studies. Doing so, we discuss the impact of species misidentification and poor accessibility of vouchers in the field of sponge natural products. We advocate for stricter voucher guidelines in natural product journals and propose a common protocol of good practice, in the hope of reducing misidentifications in sponge studies, ensure reproducibility of studies, and facilitate follow-up work on the original material.     

Essential oil content and composition of Indian sandalwood (Santalum album) in Sri Lanka

Santalum album (Indian Sandalwood) is found in the mountainous regions of the intermediate zone of Sri Lanka. Few studies have been conducted on sandalwood ecology in this region, and ours is the first recorded study of essential oil content and chemical composition of heartwood. We harvested two trees with State permission and took crosssections for analysis. We demonstrated a difference in the heartwood formation and oil yield of the trees. The composition of the oil was found to be consistent between trees and along the trunk of the tree. Main aromatic compounds were santalols and other compounds are recorded in lesser quantities. Results of this study comply with the other published work on sandalwood elsewhere. This initial study on S. album in Sri Lanka provided promising results for the future of sandalwood agro- forestry.     

Effects of Phosphorus Additions on Lead,Cadmium, and Zinc Bioavailabilities in a Metal-Contaminated Soil

The use of phosphorus (P) to reduce lead (Pb)bioavailability is being proposed as an alternative to excavationand disposal as a remedial technology for Pb-contaminated soilsin residential areas. The objective of this study was todetermine the influence of P sources and rates andCaCO₃additions on the bioavailabilities of Pb, cadmium (Cd), and zinc(Zn) in a contaminated soil material using plants, a sequentialextraction procedure, and ion activities in equilibrium solutionas indicators. A contaminated soil containing 370 mg kg^-1 Cd, 2800 mg kg^-1 Pb and 29100 mg kg^-1 Zn was amended ina factorial arrangement of CaCO₃ (0 or 2000 mg kg^-1) and P as rock phosphate or KH₂PO₄ at 0:1, 2:1 or 4:1P:Pb mole ratios. A pot study was conducted using sorghum-sudangrass (Sorghum bicolor L. Moench). The addition of P did not influence Pb concentrations in plant tissue and had little effect on Cd concentrations. An interaction between P source and level of P addition was found for Zn concentrations in plant tissue; concentrations increased with increasing amounts of P from KH₂PO₄ anddecreased with increasing amounts of P from rock phosphate. Sequential extraction results suggested a much greater reduction in Pb bioavailability from treatment withKH₂PO₄ than with rock phosphate and that P influencedthe fractionations of Cd and Zn. Activities of Cd²⁺,Pb²⁺, and Zn²⁺ in equilibrium solutions generally weredecreased by rock phosphate and increased by KH₂PO₄. Saturation indices suggested the addition ofKH₂PO₄shifted the soil equilibrium from octavite to hydroxypyromorphite, whereas solid-phase control of Cd²⁺ andZn²⁺ was not influenced by soil amendments. A soluble Psource was more effective in reducing Pb bioavailability thanrock phosphate but had variable effects on Cd and Znbioavailabilities.     

Restoration of the adipogenic gene expression by naringenin and naringin in 3T3-L1 adipocytes

BackgroundNaringenin and its glycoside naringin are well known citrus flavonoids with several therapeutic benefits. Although the anti-adipogenic effects of naringenin and naringin have been reported previously, the detailed mechanism underlying their anti-adipogenesis effects is poorly understood.ObjectivesThis study examined the anti-adipogenic effects of naringenin and naringin by determining differential gene expression patterns in these flavonoids-treated 3T3-L1 adipocytes.MethodsLipid accumulation and triglyceride (TG) content were determined by Oil red O staining and TG assay. Glucose uptake was measured using a 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose fluorescent d-glucose analog. The phosphorylation levels of AMP-activated protein kinase (AMPK) and acetyl Co-A carboxylase (ACC) were observed via Western blot analysis. Differential gene expressions in 3T3-L1 adipocytes were evaluated via RNA sequencing analysis.ResultsNaringenin and naringin inhibited both lipid accumulation and TG content, increased phosphorylation levels of both AMPK and ACC and decreased the expression level of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR) in 3T3-L1 adipocytes. RNA sequencing analysis revealed that 32 up-regulated (> 2-fold) and 17 down-regulated (< 0.6-fold) genes related to lipid metabolism, including Acaca, Fasn, Scd1, Mogat1, Dgat, Lipin1, Cpt1a, and Lepr, were normalized to the control level in naringenin-treated adipocytes. In addition, 25 up-regulated (> 2-fold) and 25 down-regulated (< 0.6-fold) genes related to lipid metabolism, including Acaca, Fasn, Fabp5, Scd1, Srebf1, Hmgcs1, Cpt1c, Lepr, and Lrp1, were normalized to the control level by naringin.ConclusionsThe results indicate that naringenin and naringin have anti-adipogenic potentials that are achieved by normalizing the expression levels of lipid metabolism-related genes that were perturbed in differentiated 3T3-L1 cells.     

Anti-inflammatory effect of sulforaphane on LPS-stimulated RAW 264.7 cells and ob/ob mice

BackgroundSulforaphane (SFN) is an isothiocyanate compound present in cruciferous vegetables. Although the anti-inflammatory effects of SFN have been reported, the precise mechanism related to the inflammatory genes is poorly understood.ObjectivesThis study examined the relationship between the anti-inflammatory effects of SFN and the differential gene expression pattern in SFN treated ob/ob mice.MethodsNitric oxide (NO) level was measured using a Griess assay. The inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels were analyzed by Western blot analysis. Pro-inflammatory cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, and IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). RNA sequencing analysis was performed to evaluate the differential gene expression in the liver of ob/ob mice.ResultsThe SFN treatment significantly attenuated the iNOS and COX-2 expression levels and inhibited NO, TNF-α, IL-1β, and IL-6 production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. RNA sequencing analysis showed that the expression levels of 28 genes related to inflammation were up-regulated (> 2-fold), and six genes were down-regulated (< 0.6-fold) in the control ob/ob mice compared to normal mice. In contrast, the gene expression levels were restored to the normal level by SFN. The protein-protein interaction (PPI) network showed that chemokine ligand (Cxcl14, Ccl1, Ccl3, Ccl4, Ccl17) and chemokine receptor (Ccr3, Cxcr1, Ccr10) were located in close proximity and formed a “functional cluster” in the middle of the network.ConclusionsThe overall results suggest that SFN has a potent anti-inflammatory effect by normalizing the expression levels of the genes related to inflammation that were perturbed in ob/ob mice.     

Heartwood assessment of natural <Emphasis Type="Italic">Santalum album</Emphasis> populations for agroforestry development in Sri Lanka

Sandalwood (Santalum album) is developing as an important agroforestry crop in Sri Lanka. The value of S. album depends upon the oil content in the heartwood and its composition with reference to sesquiterpene alcohols cis-α-santalol and cis-β-santalol. According to the popular belief in Sri Lanka, certain S. album trees do not produce oil even after maturity. Therefore the present study was conducted to identify the presence and the variation of essential oil, its composition and the variation of growth parameters of nine distinctive S. album populations growing under different agroecological zones in Sri Lanka. According to the results, heartwood content, oil content and its constituents varied within and between the populations. It was interesting to observe that cis-α-santalol and cis-β-santalol were not detected in certain S. album trees though the oil contents of those trees were higher than the average. Heartwood content of the trees did not show a correlation with oil content, dbh and height. However, the oil content was significantly correlated with tree dbh and height. Majority of the trees (62 %) had heartwood essential oil in compliance to ISO standards; only a 31 % of the total sampled trees had the essential oil content above 2 % (w/w). Dry mountainous Badulla district had the highest percentage of trees complying the ISO standards. These findings are vital for identifying suitable sources for agroforestry propagation of S. album.     

Adequacy of vitamin A and fat in the breast milk of lactating women in south Sri Lanka

OBJECTIVE: To determine vitamin A (retinol) and fat concentrations in breast milk during early lactation. METHODS: Healthy lactating women (n 88) aged between 18 and 35 years were randomly selected for the study from urban, semi-urban, rural and estate (plantation) sectors of Galle District. Their anthropometry was recorded; breast milk samples were collected from the right breast one hour after the last feed. Breast milk retinol was determined by HPLC and fat content by the crematocrit method. RESULTS: Subjects were in the 2nd to 9th month of lactation. Retinol concentrations of the breast milk samples ranged from 0.10 to 2.46 micromol/l, with a mean of 0.50 micromol/l, and correlated positively with parity (Pearson correlation coefficient, r = 0.307; P = 0.01) and negatively with period of lactation (r = -0.209; P = 0.05). The fat content of breast milk ranged between 5.09 and 56.46 g/l with a mean of 26.95 g/l. A significant difference in either breast milk fat or retinol content and mean birth weight of the babies was not seen between the groups. The ratio of retinol to fat in breast milk was positively correlated with weight (r = 0.274; P = 0.01) and height (r = 0.328; P < 0.001) of the mothers. CONCLUSIONS: In this primary investigation on breast milk quality the fat content was found to be marginal; the majority of lactating mothers (92.0%) were not providing the minimum daily requirement (1.05 micromol/l) of retinol to their babies.     

Dissolution kinetics of macronutrient fertilizers coated with manufactured zinc oxide nanoparticles

The solubility of Zn in Zn fertilizers plays an important role in the agronomic effectiveness of the fertilizer. On the basis of thermodynamics, zinc oxide (ZnO) nanoparticles (NPs) should dissolve faster and to a greater extent than bulk ZnO particles (equivalent spherical diameter >100 nm). These novel solubility features of ZnO NPs might be exploited to improve the efficiency of Zn fertilizers. In this study, we compared the Zn solubility and dissolution kinetics of ZnO nanoparticles and bulk ZnO particles coated onto two selected granular macronutrient fertilizers, urea and monoammonium phosphate (MAP). The main Zn species on coated MAP and urea granules were zinc ammonium phosphate and ZnO, respectively. Coated MAP granules showed greater Zn solubility and faster dissolution rates in sand columns compared to coated urea granules, which may be related to pH differences in the solution surrounding the fertilizer granules. The kinetics of Zn dissolution was not affected by the size of the ZnO particles applied for coating of either fertilizer type, possibly because solubility was controlled by formation of the same compounds irrespective of the size of the original ZnO particles used for coating.