Antihypertensive effect of insect cells: In vitro and in vivo evaluation

In this study, we investigated the in vitro ACE inhibitory and in vivo antihypertensive effect of insect cell extracts. The IC₅₀ of three insect cell lines from different type and insect species origin: S2 (embryo, Drosophila melanogaster), Sf21 (ovary, Spodoptera frugiperda) and Bm5 (ovary, Bombyx mori), were evaluated. Most interesting results were that the IC₅₀ values ranged between 0.4 and 0.9 mg/ml, and that an extra hydrolysis with gastrointestinal enzymes did not increase the ACE inhibitory activity conspicuously. Finally, a single oral administration with a gavage of 150 mg cell extract/kg BW to spontaneous hypertensive rats (SHR) significantly decreased (p < 0.05) their systolic blood pressure (SBP) with 5-6% (9-12 mm Hg) compared to the controls at 6 h post-administration. Here the undigested and digested insect S2 cell extracts were equal in activity to lower the SBP. To the best of our knowledge, this is the first report of in vivo antihypertensive activity of insect cell extracts and this without an extra digestion requirement.     

Protocorm culture of Dendrobium candidum in balloon type bubble bioreactors

Protocorm cultures of Dendrobium candidum were established in balloon type bubble bioreactors using Murashige and Skoog (MS) medium with 0.5 mg l⁻¹ α-naphthaleneacetic acid (NAA), 2.5% (w/v) sucrose, 5:25 mM NH₄:NO₃ and 1% (v/v) banana homogenate for the production of biomass and bioactive compounds. In 3 l bioreactor containing 2 l medium, a maximum protocorm biomass (21.0 g l⁻¹ dry biomass) and also optimum quantities of total polysaccharides (389.3 mg g⁻¹ DW), coumarins (18.0 mg g⁻¹ DW), polyphenolics (11.9 mg g⁻¹ DW), and flavonoids (4.5 mg g⁻¹ DW) were achieved after 7 weeks of culture. Based on these studies, 5 and 10 l bioreactor cultures were established to harvest 80 g and 160 g dry biomass. In 10 l bioreactors, the protocorms grown were accumulated with optimal levels of polysaccharides (424.1 mg g⁻¹ DW), coumarins (15.8 mg g⁻¹ DW), polyphenols (9.03 mg g⁻¹ DW) and flavonoids (4.7 mg g⁻¹ DW). The bioreactor technology developed here will be useful for the production of important bioactive compounds from D. candidum.     

Bioactive lipid mediators in plasma are predictors of preeclampsia irrespective of aspirin therapy

There are few early biomarkers to identify pregnancies at risk of preeclampsia (PE) and abnormal placental function. In this cross-sectional study, we utilized targeted ultra-performance liquid chromatography-ESI MS/MS and a linear regression model to identify specific bioactive lipids that serve as early predictors of PE. Plasma samples were collected from 57 pregnant women prior to 24-weeks of gestation with outcomes of either PE (n = 26) or uncomplicated term pregnancies (n = 31), and the profiles of eicosanoids and sphingolipids were evaluated. Significant differences were revealed in the eicosanoid, (±)11,12 DHET, as well as multiple classes of sphingolipids; ceramides, ceramide-1-phosphate, sphingomyelin, and monohexosylceramides; all of which were associated with the subsequent development of PE regardless of aspirin therapy. Profiles of these bioactive lipids were found to vary based on self-designated race. Additional analyses demonstrated that PE patients can be stratified based on the lipid profile as to PE with a preterm birth linked to significant differences in the levels of 12-HETE, 15-HETE, and resolvin D1. Furthermore, subjects referred to a high-risk OB/GYN clinic had higher levels of 20-HETE, arachidonic acid, and Resolvin D1 versus subjects recruited from a routine, general OB/GYN clinic. Overall, this study shows that quantitative changes in plasma bioactive lipids detected by ultra-performance liquid chromatography-ESI-MS/MS can serve as an early predictor of PE and stratify pregnant people for PE type and risk.     

A reduction in temperature induces bioactive red pigment production in a psychrotolerant Penicillium sp. GEU_37 isolated from Himalayan soil

Filamentous fungi are being globally explored for the production of industrially important bioactive compounds including pigments. In the present study, a cold and pH tolerant fungus strain Penicillium sp (GEU_37), isolated from the soil of Indian Himalaya, is characterized for the production of natural pigments as influenced by varying temperature conditions. The fungal strain produces a higher sporulation, exudation, and red diffusible pigment in Potato Dextrose (PD) at 15 °C as compared to 25 °C. In PD broth, a yellow pigment was observed at 25 °C. While measuring the effect of temperature and pH on red pigment production by GEU_37, 15 °C and pH 5, respectively, were observed to be the optimum conditions. Similarly, the effect of exogenous carbon and nitrogen sources and mineral salts on pigment production by GEU_37 was assessed in PD broth. However, no significant enhancement in pigmentation was observed. Chloroform extracted pigment was separated using thin layer chromatography (TLC) and column chromatography. The two separated fractions i.e., fractions I and II with Rf values 0.82 and 0.73, exhibited maximum light absorption, λ_max, at 360 nm and 510 nm, respectively. Characterization of pigments using GC–MS showed the presence of the compounds such as phenol, 2,4-bis (1,1-dimethylethyl) and eicosene from fraction I and derivatives of coumarine, friedooleanan, and stigmasterole in fraction II. However, LC-MS analysis detected the presence of derivatives of compound carotenoids from fraction II as well as derivative of chromenone and hydroxyquinoline as major compounds from both the fractions along with other numerous important bioactive compounds. The production of such bioactive pigments under low temperature conditions suggest their strategic role in ecological resilience by the fungal strain and may have biotechnological applications.     

Dysregulated ceramide metabolism in mouse progressive dermatitis resulting from constitutive activation of Jak1

Coordinated lipid metabolism contributes to maintaining skin homeostasis by regulating skin barrier formation, immune reactions, thermogenesis, and perception. Several reports have documented the changes in lipid composition in dermatitis, including in atopic dermatitis (AD); however, the specific mechanism by which these lipid profiles are altered during AD pathogenesis remains unknown. Here, we performed untargeted and targeted lipidomic analyses of an AD-like dermatitis model resulting from constitutive activation of Janus kinase 1 (Spade mice) to capture the comprehensive lipidome profile during dermatitis onset and progression. We successfully annotated over 700 skin lipids, including glycerophospholipids, ceramides, neutral lipids, and fatty acids, many of which were found to be present at significantly changed levels after dermatitis onset, as determined by the pruritus and erythema. Among them, we found the levels of ceramides composed of nonhydroxy fatty acid and dihydrosphingosine containing very long-chain (C22 or more) fatty acids were significantly downregulated before AD onset. Furthermore, in vitro enzyme assays using the skin of Spade mice demonstrated the enhancement of ceramide desaturation. Finally, we revealed topical application of ceramides composed of nonhydroxy fatty acid and dihydrosphingosine before AD onset effectively ameliorated the progression of AD symptoms in Spade mice. Our results suggest that the disruption in epidermal ceramide composition is caused by boosting ceramide desaturation in the initiation phase of AD, which regulates AD pathogenesis.     

Rapid transmembrane diffusion of ceramide and dihydroceramide spin-labelled analogues in the liquid ordered phase

In order to study the basic physical phenomena underlying complex lipid transbilayer movement in biological membranes, we have measured the transmembrane diffusion of spin-labelled analogues of sphingolipids in phosphatidylcholine (PC) large unilamellar vesicles in the absence or presence of cholesterol, going from a fluid ( liquid disordered) l_d, phase to a more viscous, liquid ordered (l_o), phase. We have found cholesterol to reduce the transverse diffusion of glucosylceramide (GlcCer) and galactosylceramide (GalCer) in a concentration-dependent manner. However, surprisingly, we could neither detect any influence of cholesterol on the rapid flip-flop of ceramide nor on the flip-flop of dihydroceramide, for which the τ_1/2 of flip-flop remains in the order of 1 minute at 20°C in the presence of cholesterol. As a consequence of rapid flip-flop of ceramide in both the l_o and the l_d phase, ceramide is likely to distribute between the two monolayers of a membrane, and could in principle partition into segregated domains in each side of the plasma membrane of eukaryotic cells.