Synthesis and protective effect of scutellarein on focal cerebral ischemia/reperfusion in rats

Scutellarein, the main metabolite of scutellarin in vivo, has relatively better solubility, bioavailability and bio-activity than scutellarin. However, compared with scutellarin, it is very difficult to obtain scutellarein from Nature. Therefore, the present study focused on establishing an efficient route for the synthesis of scutellarein by hydrolyzing scutellarin. Neurological deficit score and cerebral infarction volume with the administration of scutellarein were then used to compare its neuroprotective effects on focal cerebral ischemia/reperfusion in rats induced by middle cerebral artery occlusion (MCAO) with those of scutellarin. The results showed that scutellarein had better protective effect on focal cerebral ischemia/reperfusion than scutellarin, which laid the foundation for further research and development of scutellarein as a promising candidate for ischemic cerebro-vascular disease.     

Neuroprotective effects of Tilia americana var. mexicana on damage induced by cerebral ischaemia in mice

Tilia americana var. mexicana (T. americana) is a plant widely used in Mexico for its medicinal properties on the central nervous system. In the present study, we designed a protocol to investigate the neuroprotective effects of non-polar and polar extracts of T. americana on damage induced by cerebral ischaemia in mice. Vehicle or extracts were administered immediately after ischaemia. Functional neurological deficit, survival percentage and infarct area were determined in each experimental group. Results showed that groups treated with non-polar or polar extracts of T. americana had increased survival rate, improved neurological deficits and diminished the infarct area in relation to the ischaemic group. In conclusion, this study confirms the neuroprotective activity of T. americana, suggests a possible synergism between non-polar and polar constituents and supports its potential as a useful aid in the clinical management of stroke.     

Enantioselective comprehensive two‐dimensional gas chromatography of lavender essential oil

The enantiomeric composition of several chiral markers in lavender essential oil was studied by flow modulated comprehensive two‐dimensional gas chromatography operated in the reverse flow mode and hyphenated to flame ionization and quadrupole mass spectrometric detection. Two capillary column series were used in this study, 2,3‐di‐O‐ethyl‐6‐O‐tert‐butyldimethylsilyl‐β‐cyclodextrin or 2,3,6‐tri‐O‐methyl‐β‐cyclodextrin, as the chiral column in the first dimension and α polyethylene glycol column in the second dimension. Combining the chromatographic data obtained on these column series, the enantiomeric and excess ratios for α‐pinene, β‐pinene, camphor, lavandulol, borneol, and terpinen‐4‐ol were determined. This maybe a possible route to assess the authenticity of lavender essential oil.     

Development of fast enantioselective gas-chromatographic analysis using gas-chromatographic method-translation software in routine essential oil analysis (lavender essential oil)

The study aimed to find the best trade-off between separation of the most critical peak pair and analysis time, in enantioselective GC–FID and GC–MS analysis of lavender essential oil, using the GC method-translation approach. Analysis conditions were first optimized for conventional 25 m × 0.25 mm inner diameter (d_c) column coated with 6^I–VII-O-tert-butyldimethylsilyl-2^I–VII-3^I–VII-O-ethyl-β-cyclodextrin (CD) as chiral stationary phase (CSP) diluted at 30% in PS086 (polymethylphenylpolysiloxane, 15% phenyl), starting from routine analysis. The optimal multi-rate temperature program for a pre-set column pressure was determined and then used to find the pressures producing the efficiency-optimized flow (EOF) and speed-optimized flow (SOF). This method was transferred to a shorter narrow-bore (NB) column (11 m × 0.10 mm) using method-translation software, keeping peak elution order and separation. Optimization of the enantioselective GC method with the translation approach markedly reduced the analysis time of the lavender essential oil, from about 87 min with the routine method to 40 min with an optimal multi-rate temperature program and initial flow with a conventional inner diameter column, and to 15 min with FID as detector or 13.5 min with MS with a corresponding narrow-bore column, while keeping enantiomer separation and efficiency.     

Neuroprotective activity of different monosaccharide-modified gastrodin analogs

Gastrodin is a very important and well-known bioactive glycoside compound in Chinese medicine. It is also known as a drug with neuroprotective function. Here, a practical diversified synthesis of a series of gastrodin analogs was reported, which involved four-step procedures consisting of bromination, oxidation, etherification, and reduction. Various gastrodin analogs were obtained in good yields. The compound 4c in this study has a good neuroprotective function: it can significantly downregulate tumor necrosis factor-α and inducible nitric oxide synthase protein levels. The results of this study can provide a research basis for the development of neuroprotective drugs.     

Jasmonic acid changes the composition of essential oil isolated from narrow-leaved lavender propagated in in vitro cultures

The aim of the present study was to determine the effect of jasmonic acid added to the culture medium on composition of Lavandula angustifolia essential oils. The chemical composition was determined by gas chromatography coupled to mass detector (GC/MS). The experiment was conducted with the use of MS medium supplemented with increasing concentration of JA (0.2, 0.5, 1, 1.5 mg?dm^?3). It was found that the analysed essential oils varied in terms of chemical composition depending on the content of JA in the medium. All obtained essential oils were characterised by a high content of σ-cadinene (17.06–29.64%), borneol (6.66–17.47%), caryophyllene oxide (8.30–14.01%), τ-cadinol (4.87–9.16%), beta-caryophyllene (3.54–6.57%), 1.8-cineole (1.94–5.87%), β-pinene (1.48–3.05%), geranyl acetate (0.56–2.14%) and myrtenal (0.65–2.14%).     

Ginkgo biloba extract preserves pyruvate and enhances ascorbate in the cortex of gerbils during focal cerebral ischemia. A microdialysis-liquid chromatography study

The aim of this study was to evaluate dynamic changes in energy-related metabolites in the cortex of gerbils subjected to focal cerebral ischemia after pretreatment with Ginkgo biloba extract. Focal cerebral ischemia was induced by occlusion of the right common carotid artery and the right middle cerebral artery for 60 min in anesthetized gerbils. A microdialysis probe was inserted into the cortex to monitor extracellular lactate. pyruvate and ascorbate during ischemia and reperfusion. The present study demonstrated a dynamic decrease in pyruvate (25% of baseline) and increases in lactate (160% of baseline) and asorbate (300% of baseline) and a 5-fold increase in the lactate:pyruvate (L:P) ratio during cerebral ischemia in the control group. However. pyruvate levels were preserved and ascorbate levels were enhanced with a chronic pretreatment of Ginkgo biloba extract for 8 days (i.p., 100 mg kg(-1) day(-1)). Preservation of pyruvate and enhancement of ascorbate observed in this study may be associated with the neuroprotective effects of Ginkgo biloba extract.     

Simultaneous monitoring of extracellular glucose, pyruvate, lactate and glutamate in gerbil cortex during focal cerebral ischemia by dual probe microdialysis

The aim of this study was to monitor dynamic changes in energy-related metabolites in the cortex of gerbils subjected to cerebral ischemia by a dual probe microdialysis technique. Focal cerebral ischemia was produced in anesthetized gerbils by occlusion of the right common carotid artery and the right middle cerebral artery for 60 min. Two microdialysis probes were inserted into both sides of the cortex to simultaneously monitor extracellular glucose, lactate, pyruvate and glutamate. Dynamic and comparative changes in these analytes, on the ipsilateral and contralateral sides of the brain, were simultaneously monitored by liquid chromatography and a microdialysis analyzer. The present study demonstrated decreases in glucose and pyruvate, increases in lactate and glutamate on the ipsilateral side whereas all analytes remain constant on the contralateral side of cortex during cerebral ischemia. In vitro recovery of each microdialysis probe was performed to ensure the quality of experiments. The detection limits of pyruvate, glutamate, lactate and glucose were 0.2, 1.0, 2.0 and 20 microM, respectively. The intra- and inter-assay correlations were less than 5% in standard mixtures and pooled brain dialysates.     

Antitumor activity of nanoemulsion based on essential oil of Pinus koraiensis pinecones in MGC-803 tumor-bearing nude mice

Essential oil is the natural extract rich in terpenoids, showing various physiological activities. Our previous studies have proved that essential oil of Pinus koraiensis pinecones (PEO) can inhibit the proliferation of MGC-803 cells and promote cell apoptosis in vitro via the HIPPO/YAP signaling pathway. In this study, we prepared the PEO nanoemulsion and studied its physicochemical properties and anti-tumor activity in MGC-803 tumor-bearing nude mice. The PEO nanoemulsion showed good stability, with an average particle size of 46.87 nm, a zeta potential of 34.4 mV, and a polydispersity index (PDI) of 0.121. The results of anti-tumor experiments showed that the PEO nanoemulsion can effectively inhibit the growth of tumor and promote the apoptosis. In addition, immunohistochemical results showed that the PEO nanoemulsion could inhibit the proliferation of MGC-803 cells by down-regulating the expression of YAP1/TEAD and its target proteins CTGF, AREG and GLI2 to regulate the HIPPO/YAP signaling pathway and its downstream signaling pathway. This study could provide the theoretical basis for the application of essential oils.     

Determination of the ambience duration of lavender essential oil with three perfume fixatives using the thermokinetics approach

Journal of Thermal Analysis and Calorimetry - Various cosmetic perfumes have distinct fragrance residence times. Changes in the temperature of the surroundings can decrease thermal stability....     

Water as a green solvent combined with different techniques for extraction of essential oil from lavender flowers

Using water as a green solvent with a variable geometry makes use of physical and chemical phenomena that are fundamentally different from those applied in conventional extraction techniques such as hydro-distillation, steam distillation or solvent extraction. Advantages and drawbacks of using water as a solvent with different physical and chemical states have been compared. A total of ten extraction techniques: hydro-distillation (HD), steam distillation (SD), turbo-hydro-distillation (THD), salt-hydro-distillation (NaCL-HD), enzyme-hydro-distillation (Enzyme-HD), micelle-hydro-distillation (Micelle-HD), ultrasound-hydro-distillation (US-HD) or subcritical water-hydro-distillation (SW-HD), solvent-free microwave extraction (SFME) and microwave steam distillation (MSD) were used to extract the essential oil from lavender (Lavandula L.) and their results were compared. The quantity was measured by the yield of essential oil and the quality was evaluated using the oil composition especially the content of linalyl acetate, linalool and terpin-4-ol compared with the corresponding control sample: Hydro-distillation. For environmentally friendly of the process: extraction time, total energy consumption and CO₂ emission were considered and compared with conventional hydro-distillation. The mechanism explaining the linalyl acetate degradation has been resolved by using COSMO-RS software. Based on the present experimental conditions, it is recommended that lavender oil may be produced preferably by steam distillation assisted by microwave extraction to reduce the by-product formation by various chemical reactions and to get better oil recoveries.     

Essential oil obtained from micropropagated lavender,its effect on HSF cells and application in cosmetic emulsion as a natural protective substance

The aim of the study was to determine the influence of the essential oils isolated from the field – grown and micropropagated in vitro narrow – leaved lavender of the ‘Munstead’ cultivar, on human skin cells, and their capability to synthesise procollagen. The amount of procollagen type I produced by fibroblast cells was determined using ELISA kit. Essential oil isolated from micropropagated lavender was further used as a protective ingredient against the development of microorganisms in O/W cosmetic emulsion. The presented results demonstrate that the use of 0.01, 0.001 and 0.0001% essential oils isolated from in vitro plants stimulate HSF cells to the production of procollagen. It was further performed that the tested essential oil used in the concentration of 0.1% in a cosmetic emulsion is characterised by preservative effect for cosmetic preparations for the period of 3 months.     

Microwave accelerated steam distillation of essential oil from lavender: A rapid, clean and environmentally friendly approach

A new process design and operation for microwave accelerated steam distillation (MASD) of essential oils was developed. A packed bed of lavender flowers (Lavandula angustifolia Mill., Lamiaceae) sits above the steam source generated by microwave heating. Only steam passes through it without the boiling water mixing with vegetable raw material, as is the case in hydro-distillation. MASD has been compared with a conventional technique, steam distillation (SD), for the extraction of essential oil from lavender flowers. Extraction of essential oils from lavender with MASD was better than SD in terms of energy saving, rapidity (10 min versus 90 min), product yield, cleanliness and product quality.     

Effect of laser phototherapy on wound healing following cerebral ischemia by cryogenic injury

Laser phototherapy emerges as an alternative or auxiliary therapy for acute ischemic stroke, traumatic brain injury, degenerative brain disease, spinal cord injury, and peripheral nerve regeneration, but its effects are still controversial. We have previously found that laser phototherapy immunomodulates the response to focal brain damage. Following direct cortical cryogenic injury the effects of laser phototherapy on inflammation and repair was assessed after cryogenic injury (CI) to the central nervous system (CNS) of rats. The laser phototherapy was carried out with a 780 nm AlGaAs diode laser. The irradiation parameters were: power of 40 mW, beam area of 0.04 cm(2), energy density of 3 J/cm(2) (3s) in two points (0.12 J per point). Two irradiations were performed at 3 h-intervals, in contact mode. Rats (20 non-irradiated - controls and 20 irradiated) were used. The wound healing in the CNS was followed in 6 h, 1, 7 and 14 days after the last irradiation. The size of the lesions, the neuron cell viability percentages and the amount of positive GFAP labeling were statistically compared by ANOVA complemented by Tukey's test (p<0.05). The distribution of lymphocytes, leukocytes and macrophages were also analyzed. CI created focal lesions in the cortex represented by necrosis, edema, hemorrhage and inflammatory infiltrate. The most striking findings were: lased lesions showed smaller tissue loss than control lesions in 6 h. During the first 24 h the amount of viable neurons was significantly higher in the lased group. There was a remarkable increase in the amount of GFAP in the control group by 14 days. Moreover, the lesions of irradiated animals had fewer leukocytes and lymphocytes in the first 24 h than controls. Considering the experimental conditions of this study it was concluded that laser phototherapy exerts its effect in wound healing following CI by controlling the brain damage, preventing neuron death and severe astrogliosis that could indicate the possibility of a better clinical outcome.     

Inhibition of sevoflurane postconditioning against cerebral ischemia reperfusion-induced oxidative injury in rats

The volatile anesthetic sevoflurane is capable of inducing preconditioning and postconditioning effects in the brain. In this study, we investigated the effects of sevoflurane postconditioning on antioxidant and immunity indexes in cerebral ischemia reperfusion (CIR) rats. Rats were randomly assigned to five separate experimental groups I-V. In the sham group (I), rats were subjected to the same surgery procedures except for occlusion of the middle cerebral artery and exposed to 1.0 MAC sevoflurane 90 min after surgery for 30 min. IR control rats (group II) were subjected to middle cerebral artery occlusion (MCAO) for 90 min and exposed to O? for 30 min at the beginning of reperfusion. Sevoflurane 0.5, 1.0 and 1.5 groups (III, IV, V) were all subjected to MCAO for 90 min, but at the beginning of reperfusion exposed to 0.5 MAC, 1.0 MAC or 1.5 MAC sevoflurane for 30 min, respectively. Results showed that sevoflurane postconditioning can decrease serum tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nitric oxide (NO), nitric oxide synthase (NOS) and increase serum interleukin-10 (IL-10) levels in cerebral ischemia reperfusion rats. In addition, sevoflurane postconditioning can still decrease blood lipid, malondialdehyde (MDA) levels, infarct volume and increase antioxidant enzymes activities, normal pyramidal neurons density in cerebral ischemia reperfusion rats. It can be concluded that sevoflurane postconditioning may decrease blood and brain oxidative injury and enhance immunity indexes in cerebral ischemia reperfusion rats.