Displaying publications 61 - 80 of 1880 in total

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  1. Trends of reactive hyperaemia responses to repetitive loading on skin tissue of rats - Implications for pressure ulcer prevention
    Yapp JH, Kamil R, Rozi M, Mohtarrudin N, Loqman MY, Ezamin AR, et al.
    J Tissue Viability, 2017 Aug;26(3):196-201.
    PMID: 28438463 DOI: 10.1016/j.jtv.2017.03.002
    Tissue recovery is important in preventing tissue deterioration, which is induced by pressure and may lead to pressure ulcers (PU). Reactive hyperaemia (RH) is an indicator used to identify people at risk of PU. In this study, the effect of different recovery times on RH trend is investigated during repetitive loading. Twenty-one male Sprague-Dawley rats (seven per group), with body weight of 385-485 g, were categorised into three groups and subjected to different recovery times with three repetitive loading cycles. The first, second, and third groups were subjected to short (3 min), moderate (10 min), and prolonged (40 min) recovery, respectively, while fixed loading time and pressure (10 min and 50 mmHg, respectively). Peak hyperaemia was measured in the three cycles to determine trends associated with different recovery times. Three RH trends (increasing, decreasing, and inconsistent) were observed. As the recovery time is increased (3 min vs. 10 min vs. 40 min), the number of samples with increasing RH trend decreases (57% vs. 29% vs. 14%) and the number of samples with inconsistent RH trend increases (29% vs. 57% vs. 72%). All groups consists of one sample with decreasing RH trend (14%). Results confirm that different recovery times affect the RH trend during repetitive loading. The RH trend may be used to determine the sufficient recovery time of an individual to avoid PU development.
    Matched MeSH terms: Pressure Ulcer/prevention & control; Pressure/adverse effects
  2. Stress distributions in maxillary central incisors restored with various types of post materials and designs
    Madfa AA, Kadir MR, Kashani J, Saidin S, Sulaiman E, Marhazlinda J, et al.
    Med Eng Phys, 2014 Jul;36(7):962-7.
    PMID: 24834856 DOI: 10.1016/j.medengphy.2014.03.018
    Different dental post designs and materials affect the stability of restoration of a tooth. This study aimed to analyse and compare the stability of two shapes of dental posts (parallel-sided and tapered) made of five different materials (titanium, zirconia, carbon fibre and glass fibre) by investigating their stress transfer through the finite element (FE) method. Ten three-dimensional (3D) FE models of a maxillary central incisor restored with two different designs and five different materials were constructed. An oblique loading of 100 N was applied to each 3D model. Analyses along the centre of the post, the crown-cement/core and the post-cement/dentine interfaces were computed, and the means were calculated. One-way ANOVAs followed by post hoc tests were used to evaluate the effectiveness of the post materials and designs (p=0.05). For post designs, the tapered posts introduced significantly higher stress compared with the parallel-sided post (p<0.05), especially along the centre of the post. Of the materials, the highest level of stress was found for stainless steel, followed by zirconia, titanium, glass fibre and carbon fibre posts (p<0.05). The carbon and glass fibre posts reduced the stress distribution at the middle and apical part of the posts compared with the stainless steel, zirconia and titanium posts. The opposite results were observed at the crown-cement/core interface.
    Matched MeSH terms: Pressure
  3. Fulltext Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees
    Al-Fakih E, Arifin N, Pirouzi G, Mahamd Adikan FR, Shasmin HN, Abu Osman NA
    J Biomed Opt, 2017 Aug;22(8):1-8.
    PMID: 28822140 DOI: 10.1117/1.JBO.22.8.087001
    This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction.
    Matched MeSH terms: Pressure*
  4. Fulltext Pharmacokinetics of Free Oxytetracycline and Oxytetracycline Loaded Cockle Shell Calcium Carbonate-Based Nanoparticle in BALB/c Mice
    Idris SB, Abdul Kadir A, Abdullah JFF, Ramanoon SZ, Basit MA, Abubakar MZZA
    Front Vet Sci, 2020;7:270.
    PMID: 32613011 DOI: 10.3389/fvets.2020.00270
    The development and utilization of nano-antibiotics is currently gaining attention as a possible solution to antibiotic resistance. The aim of this study was therefore to determine the pharmacokinetics of free oxytetracycline (OTC) and oxytetracycline loaded cockle shell calcium carbonate-based nanoparticle (OTC-CNP) after a single dose of intraperitoneal (IP) administration in BALB/c mice. A total of 100 female BALB/c mice divided into two groups of equal number (n = 50) were administered with 10 mg/kg OTC and OTC-CNP, respectively. Blood samples were collected before and post-administration from both groups at time 0, 5, 10, 15, and 30 min and 1, 2, 6, 24, and 48 h, and OTC plasma concentration was quantified using a validated HPLC-UV method. The pharmacokinetic parameters were analyzed using a non-compartment model. The Cmax values of OTC in OTC-CNP and free OTC treated group were 64.99 and 23.53 μg/ml, respectively. OTC was detected up to 24 h in the OTC-CNP group as against 1 h in the free OTC group following intraperitoneal administration. In the OTC-CNP group, the plasma elimination rate of OTC was slower while the half-life, the area under the curve, and the volume of the distribution were increased. In conclusion, the pharmacokinetic profile of OTC in the OTC-CNP group differs significantly from that of free OTC. However, further studies are necessary to determine the antibacterial efficacy of OTC-CNP for the treatment of bacterial diseases.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  5. Fulltext Combining In Silico and In Vitro Studies to Evaluate the Acetylcholinesterase Inhibitory Profile of Different Accessions and the Biomarker Triterpenes of Centella asiatica
    Jusril NA, Muhamad Juhari ANN, Abu Bakar SI, Md Saad WM, Adenan MI
    Molecules, 2020 Jul 24;25(15).
    PMID: 32721993 DOI: 10.3390/molecules25153353
    Alzheimer's disease (AD) is a neurodegenerative disease and the most cause of dementia in elderly adults. Acetylcholinesterase (AChE) is an important beneficial target for AD to control cholinergic signaling deficit. Centella asiatica (CA) has proven to be rich with active ingredients for memory enhancement. In the present study, the chemical profiling of three accession extracts of CA namely SECA-K017, SECA-K018, and, SECA-K019 were performed using high-performance liquid chromatography (HPLC). Four biomarker triterpene compounds were detected in all CA accessions. Quantitative analysis reveals that madecassoside was the highest triterpene in all the CA accessions. The biomarker compounds and the ethanolic extracts of three accessions were investigated for their acetylcholinesterase (AChE) inhibitory activity using Ellman's spectrophotometer method. The inhibitory activity of the triterpenes and accession extracts was compared with the standard AChE inhibitor eserine. The results from the in vitro study showed that the triterpene compounds exhibited an AChE inhibitory activity with the half-maximal inhibitory concentration (IC50) values between 15.05 ± 0.05 and 59.13 ± 0.18 µg/mL. Asiatic acid was found to possess strong AChE inhibitory activity followed by madecassic acid. Among the CA accession extracts, SECA-K017 and SECA-K018 demonstrated a moderate AChE inhibitory activity with an IC50 value of 481.5 ± 0.13 and 763.5 ± 0.16 µg/mL, respectively from the in silico docking studies, it is observed that asiatic acid and madecassic acid showed very good interactions with the active sites and fulfilled docking parameters against AChE. The present study suggested that asiatic acid and madecassic acid in the CA accessions could be responsible for the AChE inhibitory action and could be used as markers to guide further studies on CA as potential natural products for the treatment of AD.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  6. Fulltext Inhibitory Effects of Raw-Extract Centella asiatica (RECA) on Acetylcholinesterase, Inflammations, and Oxidative Stress Activities via In Vitro and In Vivo
    Hafiz ZZ, Amin M'M, Johari James RM, Teh LK, Salleh MZ, Adenan MI
    Molecules, 2020 Feb 17;25(4).
    PMID: 32079355 DOI: 10.3390/molecules25040892
    Centella asiatica (C. asiatica) is one of the medicinal plants that has been reported to exert comprehensive neuroprotection in vitro and in vivo. In view of this, the present study was performed to investigate the effect of ethanolic extract of C. asiatica, designated as raw-extract of C. asiatica (RECA) in reducing the acetylcholinesterase (AChE), inflammations, and oxidative stress activities via both in vitro (SH-SY5Y and RAW 264.7 cells) and in vivo (Sprague Dawley rats). Quantitative high-performance liquid chromatography analysis reveals that RECA contains a significantly high proportion of glycosides than the aglycones with madecassoside as the highest component, followed by asiaticoside. Treatment of SH-SY5Y cells with RECA significantly reduced the AChE activity in a concentration-dependent manner with an IC50 value of 31.09 ± 10.07 µg/mL. Furthermore, the anti-inflammatory and antioxidant effects of RECA were evaluated by lipopolysaccharides (LPS)-stimulated RAW 264.7 cells. Our results elucidated that treatment with RECA significantly suppressed the level of pro-inflammatory cytokine/mediators and oxidative stress released in a concentration-dependent manner. Interestingly, these patterns of inhibition were consistent as observed in the LPS-induced neuroinflammation Sprague Dawley rats' model. The highest concentration used in the two models presented the most significant results. Herein, our findings strongly suggest that RECA may offer therapeutic potential for the treatment of Alzheimer's disease through inhibiting the AChE, inflammation, and oxidative stress activities.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  7. Fulltext Predictors of Nonalcoholic Fatty Liver Disease Among Middle-Aged Iranians
    Etminani R, Manaf ZA, Shahar S, Azadbakht L, Adibi P
    Int J Prev Med, 2020;11:113.
    PMID: 33088441 DOI: 10.4103/ijpvm.IJPVM_274_19
    Background: The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Therefore, we sought to determine the most important predictors of NAFLD among middle-aged men and women in Isfahan, Iran.

    Methods: A total of 413 individuals (163 men and 250 women) aged 30-60 years were selected by stratified random sampling. The participants had safe alcohol consumption habits (<2 drinks/day) and no symptoms of hepatitis B and C. NAFLD was diagnosed through ultrasound. Blood pressure, anthropometric, and body composition measurements were made and liver function tests were conducted. Biochemical assessments, including the measurement of fasting blood sugar (FBS) and ferritin levels, as well as lipid profile tests were also performed. Metabolic syndrome was evaluated according to the International Diabetes Federation (IDF) criteria.

    Results: The overall prevalence of ultrasound-diagnosed NAFLD was 39.3%. The results indicated a significantly higher prevalence of NAFLD in men than in women (42.3% vs 30.4%; P < 0.05). Binary logistic regression analysis was performed to determine the significant variables as NAFLD predictors. Overall, male gender, high body mass index (BMI), high alanine aminotransferase (ALT), high FBS, and high ferritin were identified as the predictors of NAFLD. The only significant predictors of NAFLD among men were high BMI and high FBS. These predictors were high BMI, high FBS, and high ferritin in women (P < 0.05 for all variables).

    Conclusions: The metabolic profile can be used for predicting NAFLD among men and women. BMI, FBS, ALT, and ferritin are the efficient predictors of NAFLD and can be used for NAFLD screening before liver biopsy.

    Matched MeSH terms: Blood Pressure
  8. Fulltext The capability of fiber Bragg grating sensors to measure amputees' trans-tibial stump/socket interface pressures
    Al-Fakih EA, Osman NA, Eshraghi A, Adikan FR
    Sensors (Basel), 2013 Aug 12;13(8):10348-57.
    PMID: 23941909 DOI: 10.3390/s130810348
    This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ~0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction.
    Matched MeSH terms: Transducers, Pressure*
  9. Biochemical and nutritional components of selected honey samples
    Chua LS, Adnan NA
    Acta Sci Pol Technol Aliment, 2014 Apr-Jun;13(2):169-79.
    PMID: 24876312
    The purpose of this study was to investigate the relationship of biochemical (enzymes) and nutritional components in the selected honey samples from Malaysia. The relationship is important to estimate the quality of honey based on the concentration of these nutritious components. Such a study is limited for honey samples from tropical countries with heavy rainfall throughout the year.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  10. Effects of pectinase clarification treatment on phenolic compounds of pummelo (Citrus grandis l. Osbeck) fruit juice
    Shah NN, Rahman RA, Shamsuddin R, Adzahan NM
    J Food Sci Technol, 2015 Aug;52(8):5057-65.
    PMID: 26243926 DOI: 10.1007/s13197-014-1554-9
    The purpose of this study is to investigate the changes occured on phenolic compounds between two Malaysian varieties of pummelo fruit juice: Ledang (PO55) and Tambun (PO52) post-enzymatic clarification. The changes in polyphenols composition were monitored using High Performance Liquid Chromatography Diode Array Detection and Folin Ciocalteu's method. Clarification treatment of pummelo fruit juice with a commercial pectinase was optimized based on incubation temperature, time and enzyme concentration. Both varieties of pummelo fruit juice were treated with different optimized variables which produced the highest clarities with the least effect to the juice physical quality. Tambun variety was found to have significantly more total phenolic compounds (p <0.05) in comparison to Ledang variety, possibly due to the amount of naringin. Three types of hydroxycinnamic acids (chlorogenic, caffeic and coumaric acid) and three compounds of flavanones (naringin, hesperidin and narirutin) were found in both fruit juices, where naringin and chlorogenic acid were the major contributor to the total phenolic content. Naringin, which gave out bitter aftertaste to the juice, was found to decrease, 1.6 and 0.59 % reduction in Ledang and Tambun respectively, post-enzymatic treatment. The decrease in naringin, albeit nominal, could be a potential benefit to the juice production in reducing the bitterness of the juice. Post-enzymatic analysis furthermore resulted in no significance differences (p <0.05) on the total phenolic compounds of both varieties. This study in summary provides a compositional database for Malaysian pummelo fruit juice of various phenolic compounds, which can provide useful information for evaluating the authenticity and the health benefits from the juice.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  11. Future target molecules in antiglaucoma therapy: tgf-Beta may have a role to play
    Agarwal R, Agarwal P
    Ophthalmic Res, 2010;43(1):1-10.
    PMID: 19829006 DOI: 10.1159/000246571
    Glaucoma, a leading cause of irreversible blindness, is often associated with increased resistance to aqueous outflow in trabecular tissue. Increased outflow resistance has been attributed to increased extracellular matrix (ECM) deposition in trabecular tissue. A critical balance between the synthesis and breakdown of the components of extracellular tissue is important in keeping the intraocular pressure within the normal range. Multiple mechanisms have been shown to affect ECM turnover in trabecular tissue. In this review, we examine the related literature to understand the role of TGF-beta in ECM turnover, in the development and progression of glaucoma, and in possible therapeutic strategies that can be devised by targeting the TGF-beta signaling pathways.
    Matched MeSH terms: Intraocular Pressure/drug effects
  12. Newer targets for modulation of intraocular pressure: focus on adenosine receptor signaling pathways
    Agarwal R, Agarwal P
    Expert Opin Ther Targets, 2014 May;18(5):527-39.
    PMID: 24579961 DOI: 10.1517/14728222.2014.888416
    The homeostatic role of adenosine in regulating intraocular pressure (IOP) is now widely recognized, and hence, the drugs targeting adenosine receptors have become the focus of investigation. In this review, we summarize the adenosine receptor signaling pathways, which could be potential therapeutic targets for the management of glaucoma.
    Matched MeSH terms: Intraocular Pressure/drug effects*; Intraocular Pressure/physiology
  13. Trabecular meshwork ECM remodeling in glaucoma: could RAS be a target?
    Agarwal P, Agarwal R
    Expert Opin Ther Targets, 2018 07;22(7):629-638.
    PMID: 29883239 DOI: 10.1080/14728222.2018.1486822
    INTRODUCTION: Disturbances of extracellular matrix (ECM) homeostasis in trabecular meshwork (TM) cause increased aqueous outflow resistance leading to elevated intraocular pressure (IOP) in glaucomatous eyes. Therefore, restoration of ECM homeostasis is a rational approach to prevent disease progression. Since renin-angiotensin system (RAS) inhibition positively alters ECM homeostasis in cardiovascular pathologies involving pressure and volume overload, it is likely that RAS inhibitors reduce IOP primarily by restoring ECM homeostasis. Areas covered: Current evidence showing the presence of RAS components in ocular tissue and its role in regulating aqueous humor dynamics is briefly summarized. The role of RAS in ECM remodeling is discussed both in terms of its effects on ECM synthesis and its breakdown. The mechanisms of ECM remodeling involving interactions of RAS with transforming growth factor-β, Wnt/β-catenin signaling, bone morphogenic proteins, connective tissue growth factor, and matrix metalloproteinases in ocular tissue are discussed. Expert opinion: Current literature strongly indicates a significant role of RAS in ECM remodeling in TM of hypertensive eyes. Hence, IOP-lowering effect of RAS inhibitors may primarily be attributed to restoration of ECM homeostasis in aqueous outflow pathways rather than its vascular effects. However, the mechanistic targets for RAS inhibitors have much wider distribution and consequences, which remain relatively unexplored in TM.
    Matched MeSH terms: Intraocular Pressure/drug effects
  14. Fulltext Recent advance s in pathophysiology and pharmacotherapy of glaucoma
    Agarwal R
    Medical Health Reviews, 2009;2009(1):75-93.
    MyJurnal
    Glaucoma, recognized as optic neuropathy is the second largest cause of blindness worldwide. The disease is characterized by progressive loss of retinal ganglion cells and visual field defects. The pathophysiological factors involved in the onset and progression of glaucoma are not fully understood. However, it is now well accepted that elevated intraocular pressure is not the only causative factor. The pathophysiology of glaucoma involves multiple factors that interact in a highly complex manner to favor development of glaucomatous optic neuropathy. As the knowledge of molecular mechanisms involved is expanding, more and more therapeutic targets are being recognized for the development of safe and effective pharmacotherapy of glaucoma. Although at present the intraocular pressure lowering drugs are still the first line of treatment, the prospect of introducing neuroprotective therapies that can directly protect and perhaps stimulate regeneration of dying and dead retinal ganglion cells, shows considerable promise. This review presents recent developments in the pathophysiology and pharmacotherapy of glaucoma.
    Matched MeSH terms: Intraocular Pressure
  15. Fulltext Aqueous humor TGF-β2 levels in patients with open-angle glaucoma: A meta-analysis
    Agarwal P, Daher AM, Agarwal R
    Mol Vis, 2015;21:612-20.
    PMID: 26019480
    Elevated intraocular pressure (IOP) in glaucomatous eyes is often due to increased resistance to aqueous outflow. Previous studies have shown that increased extracellular material deposition in outflow pathways leads to increased resistance to aqueous outflow, and transforming growth factor (TGF)-β seems to play a role in the deposition of extracellular material. TGF-β2 is the predominant isoform in ocular tissue. Hence, comparison of the aqueous humor TGF-β2 level between patients with open-angle glaucoma (OAG) and controls would provide direct evidence for the role of TGF-β2 in the etiology of OAG. Hence, we performed this meta-analysis to develop an accurate estimate of the changes in aqueous humor TGF-β2 levels among OAG patients.
    Matched MeSH terms: Intraocular Pressure
  16. Fulltext Connective tissue growth factor: Role in trabecular meshwork remodeling and intraocular pressure lowering
    Hassan MDS, Razali N, Abu Bakar AS, Abu Hanipah NF, Agarwal R
    Exp Biol Med (Maywood), 2023 Aug;248(16):1425-1436.
    PMID: 37873757 DOI: 10.1177/15353702231199466
    Connective tissue growth factor (CTGF) is a distinct signaling molecule modulating many physiological and pathophysiological processes. This protein is upregulated in numerous fibrotic diseases that involve extracellular matrix (ECM) remodeling. It mediates the downstream effects of transforming growth factor beta (TGF-β) and is regulated via TGF-β SMAD-dependent and SMAD-independent signaling routes. Targeting CTGF instead of its upstream regulator TGF-β avoids the consequences of interfering with the pleotropic effects of TGF-β. Both CTGF and its upstream mediator, TGF-β, have been linked with the pathophysiology of glaucomatous optic neuropathy due to their involvement in the regulation of ECM homeostasis. The excessive expression of these growth factors is associated with glaucoma pathogenesis via elevation of the intraocular pressure (IOP), the most important risk factor for glaucoma. The raised in the IOP is due to dysregulation of ECM turnover resulting in excessive ECM deposition at the site of aqueous humor outflow. It is therefore believed that CTGF could be a potential therapeutic target in glaucoma therapy. This review highlights the CTGF biology and structure, its regulation and signaling, its association with the pathophysiology of glaucoma, and its potential role as a therapeutic target in glaucoma management.
    Matched MeSH terms: Intraocular Pressure
  17. Application of the artificial neural network in quantitative structure-gradient elution retention relationship of phenylthiocarbamyl amino acids derivatives
    Tham SY, Agatonovic-Kustrin S
    J Pharm Biomed Anal, 2002 May 15;28(3-4):581-90.
    PMID: 12008137
    Quantitative structure-retention relationship(QSRR) method was used to model reversed-phase high-performance liquid chromatography (RP-HPLC) separation of 18 selected amino acids. Retention data for phenylthiocarbamyl (PTC) amino acids derivatives were obtained using gradient elution on ODS column with mobile phase of varying acetonitrile, acetate buffer and containing 0.5 ml/l of triethylamine (TEA). Molecular structure of each amino acid was encoded with 36 calculated molecular descriptors. The correlation between the molecular descriptors and the retention time of the compounds in the calibration set was established using the genetic neural network method. A genetic algorithm (GA) was used to select important molecular descriptors and supervised artificial neural network (ANN) was used to correlate mobile phase composition and selected descriptors with the experimentally derived retention times. Retention time values were used as the network's output and calculated molecular descriptors and mobile phase composition as the inputs. The best model with five input descriptors was chosen, and the significance of the selected descriptors for amino acid separation was examined. Results confirmed the dominant role of the organic modifier in such chromatographic systems in addition to lipophilicity (log P) and molecular size and shape (topological indices) of investigated solutes.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  18. HPTLC based approach for bioassay-guided evaluation of antidiabetic and neuroprotective effects of eight essential oils of the Lamiaceae family plants
    Romero Rocamora C, Ramasamy K, Meng Lim S, Majeed ABA, Agatonovic-Kustrin S
    J Pharm Biomed Anal, 2020 Jan 30;178:112909.
    PMID: 31618702 DOI: 10.1016/j.jpba.2019.112909
    A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis (EDA) was developed to screen the antioxidant, neuroprotective and antidiabetic effects in essential oils derived from lavender flower, lemon myrtle, oregano, peppermint, sage, and rosemary leaves (Lamiaceae family). HPTLC hyphenated with microchemical (DPPH•, p-anisaldehyde, and ferric chloride) derivatizations, was used to evaluate antioxidant activity, presence of phytosterols and terpenoids, and polyphenolic content, while the combination with biochemical (α-amylase and acetylcholine esterase (AChE) enzymatic) derivatizations was used to asses α-amylase and AChE inhibitory activities. The superior antioxidant activity of oregano leaf extract is attributed to the presence of high levels of aromatic compounds, like polyphenolic acids. The strongest α-amylase inhibition was observed in lemon myrtle and rosemary plus extracts due to the presence of monoterpenes. Rosemary and sage extracts exhibit the highest AChE inhibition activity, with 1 μL essential oils being more potent than the recommended daily dose of donepezil. This superior neuroprotection was attributed to the presences of di- and triterpenes that displayed strong AChE inhibition and antioxidant potential in DPPH• free radical assay. Antioxidant activity was related to phenolic content (R = 0.49), while α-amylase inhibitory activity was positively related to antioxidant activity (R = 0.20) and terpenoid/sterol content (R = 0.31). AChE inhibitory activity was correlated (R = 0.80) to the combined effect of phenolics and terpenoids. Thus, the superior AChE inhibitory and neuroprotection potential of rosemary and sage essential oils could be attributed to joint effects of main phenolic and terpene constituents. The hyphenated HPTLC method provided rapid bioanalytical profiling of highly complex essential oil samples.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  19. Comparative secondary metabolites profiling and biological activities of aerial, stem and root parts of Salvadora oleoides decne (Salvadoraceae)
    Saleem H, Ahmad I, Zengin G, Mahomoodally FM, Rehman Khan KU, Ahsan HM, et al.
    Nat Prod Res, 2020 Dec;34(23):3373-3377.
    PMID: 30678488 DOI: 10.1080/14786419.2018.1564299
    In this study, different parts (aerial, stem and root) of Salvadora oleoides Decne were investigated in order to explore their phytochemical composition and biological potential. The bioactive contents were evaluated by conventional spectrophotometric methods. Additionally, the secondary metabolite compounds were identified by UHPLC-MS analysis. Biological potential was evaluated by determining antioxidant (DPPH, FRAP, and Phosphomolybdenum) and enzyme inhibitory (butrylcholinesterase and lipoxygenase) effects. Higher total bioactive contents were found in methanolic extracts which tend to correlate with higher radical scavenging and reducing potential of these extracts. LC/MS spectrum revealed the presence of 16 different secondary metabolites belonging to terpene, glucoside and sesquiterpenoid dervivatives. Glucocleomin and emotin A were the main compounds present in all three parts. The strongest butrylcholinesterase and lipoxygenase inhibitory activity was observed for root and stem DCM extracts. Demonstrated biological potential of S. oleoides plant can trace a new road map for developing newly designed bioactive pharmaceuticals.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  20. Biological, chemical and toxicological perspectives on aerial and roots of Filago germanica (L.) huds: Functional approaches for novel phyto-pharmaceuticals
    Saleem H, Htar TT, Naidu R, Nawawi NS, Ahmad I, Ashraf M, et al.
    Food Chem Toxicol, 2019 Jan;123:363-373.
    PMID: 30419323 DOI: 10.1016/j.fct.2018.11.016
    We investigated into the effects of methanol and dichloromethane extracts from aerial and roots of Filago germanica (L.) Huds (Astearaceae) on key enzymes (cholinesterases, α-glucosidase and urease), antioxidant capabilities, cytotoxic potential and secondary metabolomics profile. Total phenolic and flavonoids were determined by spectrophotometric technique and secondary metabolites composition by UHPLC-MS. Antioxidant activities were assessed employing free radical scavenging, ferric reducing power and phosphomolybdenum assays. The cell-toxicity was evaluated by MTT assay against breast (MCF-7, MDA-MB-231), cervix (CaSki) and prostate (DU-145) cancers. Overall, methanol extracts were found to have higher total bioactive contents and antioxidant potential. UHPLC-MS analysis revealed significant variation in the secondary metabolites in the methanol extracts. The most common derivatives belong to seven groups i.e. alkaloids, benzoic acids, flavones, flavonols, flavan-3-ols, terpenoids and saponins. The major polyphenolic compounds were found to be kampferol, robinin, luteolin, ferulic acid, benzoic acid and salicylic acid. All the extracts showed moderate cholinesterases inhibition, whereas methanol extracts exhibited highest urease inhibition and all extracts presented a relatively high inhibition against α-glucosidase. Similarly, all extracts showed strong to moderate cytotoxicity with IC50 values ranging from 53.02 to 382.7 μg/mL. Overall, results have suggested F. germanica to be a lead source for novel natural products.
    Matched MeSH terms: Chromatography, High Pressure Liquid
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