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Liquid Chromatographic Analysis of α-Dicarbonyls Using Girard-T Reagent Derivatives

Lawrence GD, Rahmat R, Makahleh A, Saad B

J Chromatogr Sci, 2017 Nov 01;55(10):1043-1050.
PMID: 28977384 DOI: 10.1093/chromsci/bmx073

The measurement of α-dicarbonyls and other degradation products of sugars has become important in view of their toxicity. Although there are several methods used for their analysis, most require long reaction times to form UV absorbing or fluorescent derivatives and the nonpolar nature of commonly used derivatives necessitates relatively high concentrations of organic solvents for elution in reverse phase liquid chromatography. The present method describes the use of Girard-T reagent in a simple, one step derivatization of α-dicarbonyls and conjugated aldehydes and analysis using ion-pair reverse phase liquid chromatography. The limit of detection was in the range of 0.06-0.09 μM (4-12 ng/mL) for glyoxal, methylglyoxal, 3-deoxyglucosone and 5-hydroxymethylfurfural with good linear response and reproducibility using UV detection. The hydrazone derivatives were stable for several days in solution. The method was used to study degradation of several sugars and quantification of the target α-dicarbonyls and 5-hydroxymethylfurfural in several soft drinks.

Matched MeSH terms: Deoxyglucose/analogs & derivatives*; Deoxyglucose/analysis
Effects of age on feeding response: Focus on the rostral C1 neuron and its glucoregulatory proteins

Ramlan H, Damanhuri HA

Exp Gerontol, 2020 01;129:110779.
PMID: 31705967 DOI: 10.1016/j.exger.2019.110779

BACKGROUND: Older people are likely to develop anorexia of aging. Rostral C1 (rC1) catecholaminergic neurons in rostral ventrolateral medulla (RVLM) are recently discovered its role in food intake control. It is well established that these neurons regulate cardiovascular function.
OBJECTIVE: This study aims to determine the effect of age on the function of rostral C1 (rC1) neurons in mediating feeding response.
METHOD: Male Sprague Dawley rats at 3-months (n = 22) and 24-months (n = 22) old were used and further divided into two subgroups; 1) treatment group with 2-deoxy-d-glucose (2DG) and 2) vehicle group. Feeding hormones such as cholecystokinin (CCK), ghrelin and leptin were analysed using enzyme-linked immunosorbent assay (ELISA). Rat brain was carefully dissected to obtain the brainstem RVLM region. Further analysis was carried out to determine the level of proteins and genes in RVLM that were associated with feeding pathway. Protein expression of tyrosine hydroxylase (TH), phosphorylated TH at Serine40 (pSer40TH), AMP-activated protein kinase (AMPK), phosphorylated AMPK (phospho AMPK) and neuropeptide Y Y5 receptor (NPY5R) were determined by western blot. Expression of TH, AMPK and NPY genes were determined by real-time PCR.
RESULTS: This study showed that blood glucose level was elevated in young and old rats following 2DG administration. Plasma CCK-8 concentration was higher in the aged rats at basal and increased with 2DG administration in young rats, but the leptin and ghrelin showed no changes. Old rats showed higher TH and lower AMPK mRNA levels. Glucoprivation decreased AMPK mRNA level in young rats and decreased TH mRNA in old rats. Aged rC1 neurons showed higher NPY5R protein level. Following glucoprivation, rC1 neurons produced distinct molecular changes across age in which, in young rats, AMPK phosphorylation level was increased and in old rats, TH phosphorylation level was increased.
CONCLUSION: These findings suggest that glucose-counterregulatory responses by rC1 neurons at least, contribute to the ability of young and old rats in coping glucoprivation. Age-induced molecular changes within rC1 neurons may attenuate the glucoprivic responses. This situation may explain the impairment of feeding response in the elderly.

Matched MeSH terms: Deoxyglucose/metabolism*; Deoxyglucose/pharmacology
A lignan with glucose uptake activity in 3T3-L1 adipocytes from the stem bark of Knema patentinervia

Taher M, Amiroudine MZAM, Jaffri JM, Amri MS, Susanti D, Abd Hamid S, et al.

Pak J Pharm Sci, 2017 Jul;30(4):1335-1339.
PMID: 29039334

A new naturally occurring dibenzylbutyrolactone lignan named isocubebinic ether has been isolated from Knema patentinervia. The structure was established by spectroscopic methods, which include Ultraviolet, Infrared, Nuclear Magnetic Resonance and Mass Spectrometry. The compound showed activity in the stimulation of glucose uptake by 3T3-L1 adipocytes.

Matched MeSH terms: Deoxyglucose/metabolism
Syzygium aqueum leaf extract and its bioactive compounds enhances pre-adipocyte differentiation and 2-NBDG uptake in 3T3-L1 cells

Manaharan T, Ming CH, Palanisamy UD

Food Chem, 2013 Jan 15;136(2):354-63.
PMID: 23122070 DOI: 10.1016/j.foodchem.2012.08.056

The insulin-like and/or insulin-sensitising effects of Syzygium aqueum leaf extract and its six bioactive compounds; 4-hydroxybenzaldehyde, myricetin-3-O-rhamnoside, europetin-3-O-rhamnoside, phloretin, myrigalone-G and myrigalone-B were investigated in 3T3-L1 adipocytes. We observed that, S. aqueum leaf extract (0.04-5 μg/ml) and its six bioactive compounds (0.08-10 μM) at non-cytotoxic concentrations were effectively enhance adipogenesis, stimulate glucose uptake and increase adiponectin secretion in 3T3-L1 adipocytes. Clearly, the compounds myricetin-3-O-rhamnoside and europetin-3-O-rhamnoside showed insulin-like and insulin-sensitising effects on adipocytes from a concentration of 0.08 μM. These compounds were far better than rosiglitazone and the other isolated compounds in enhancing adipogenesis, stimulating 2-NBDG uptake and increasing adiponectin secretion at all the concentrations tested. These suggest the antidiabetic potential of S. aqueum leaf extract and its six bioactive compounds. However, further molecular interaction studies to explain the mechanisms of action are highly warranted.

Matched MeSH terms: Deoxyglucose/analogs & derivatives; Deoxyglucose/metabolism
Fulltext Evaluation on the effectiveness of 2-deoxyglucose-6-phosphate phosphatase (DOG(R)1) gene as a selectable marker for oil palm (Elaeis guineensis Jacq.) embryogenic calli transformation mediated by Agrobacterium tumefaciens

Izawati AM, Masani MY, Ismanizan I, Parveez GK

Front Plant Sci, 2015;6:727.
PMID: 26442041 DOI: 10.3389/fpls.2015.00727

DOG(R)1, which encodes 2-deoxyglucose-6-phosphate phosphatase, has been used as a selectable marker gene to produce transgenic plants. In this study, a transformation vector, pBIDOG, which contains the DOG(R)1 gene, was transformed into oil palm embryogenic calli (EC) mediated by Agrobacterium tumefaciens strain LBA4404. Transformed EC were exposed to 400 mg l(-1) 2-deoxyglucose (2-DOG) as the selection agent. 2-DOG resistant tissues were regenerated into whole plantlets on various regeneration media containing the same concentration of 2-DOG. The plantlets were later transferred into soil and grown in a biosafety screenhouse. PCR and subsequently Southern blot analyses were carried out to confirm the integration of the transgene in the plantlets. A transformation efficiency of about 1.0% was obtained using DOG(R)1 gene into the genome of oil palm. This result demonstrates the potential of using combination of DOG(R)1 gene and 2-DOG for regenerating transgenic oil palm.

Matched MeSH terms: Deoxyglucose
Fulltext Mechanistic Actions between Garcinia atroviridis Essential Oil and 2 Deoxy-d-glucose in Cultured PANC-1 Human Pancreatic Cancer Cells

Nik Mohamed Kamal NNS, Abdul Aziz FA, Tan WN, Fauzi AN, Lim V

Molecules, 2021 Jun 09;26(12).
PMID: 34207699 DOI: 10.3390/molecules26123518

Pancreatic cancer is an aggressive disease that progresses in a relatively symptom-free manner; thus, is difficult to detect and treat. Essential oil is reported to exhibit pharmacological properties, besides its common and well-known function as aromatherapy. Therefore, this study herein aimed to investigate the anti-proliferative effect of essential oil extracted from leaves of Garcinia atroviridis (EO-L) against PANC-1 human pancreatic cancer cell line. The cell growth inhibitory concentration at 50% (IC50) and selective index (SI) values of EO-L analyses were determined as 78 µg/mL and 1.23, respectively. Combination index (CI) analysis revealed moderate synergism (CI values of 0.36 to 0.75) between EO-L and 2 deoxy-d-glucose (2-DG) treatments. The treatments of PANC-1 cells with EO-L, 2-DG and EOL+2DG showed evidence of depolarization of mitochondrial membrane potential, cell growth arrest and apoptosis. The molecular mechanism causing the anti-proliferative effect between EO-L and 2-DG is potentially through pronounced up-regulation of P53 (4.40-fold), HIF1α (1.92-fold), HK2 (2.88-fold) and down-regulation of CYP3A5 (0.11-fold), as supported by quantitative mRNA expression analysis. Collectively, the current data suggest that the combination of two anti-proliferative agents, EO-L and 2-DG, can potentially be explored as therapeutic treatments and as potentiating agents to conventional therapy against human pancreatic cancer.

Matched MeSH terms: Deoxyglucose/pharmacology*
Effects of age on the glucoregulatory response following acute glucoprivation induced by 2-deoxyglucose (2DG) in the adrenal medulla of Sprague Dawley rats

Muda NA, Ramlan H, Damanhuri HA

Neuro Endocrinol. Lett., 2017 Jul;38(3):224-235.
PMID: 28759191

OBJECTIVES: Impairment in glucose homeostasis is one of the factors that may alter the feeding drive, hunger and satiety signals, which essential to maintain a sufficient level of energy for daily activities especially among the elderly. Adrenal medulla is one of the important organs that involves in glucose homeostasis through secretion of catecholamines. The catecholamines biosynthesis pathway utilizes various enzymes and protein kinases. The aims of this study are to investigate the effects of age on the biosynthetic pathway of catecholamines in adrenal medulla by determining the level of blood glucose and blood catecholamines, the gene and protein expression of biosynthetic catecholamine enzymes (TH, DBH and PNMT) as well as protein kinase substrates that involved in the phosphorylation of TH in 2DG-induced rats.
METHODS: Adrenal medulla from male Sprague Dawley rats at the age of 3-months (n=12) and 24-months (n=12) were further divided into two groups: 1) treatment group with 2DG to create glucoprivation condition and 2) the vehicle group which received normal saline as control.
RESULTS: The results showed that the level of glucose, adrenaline and noradrenaline were increased in response to acute glucoprivation conditions in both young and old rats. No age-related differences were found in the basal gene expression of the enzymes that involved in the catecholamines biosynthesis pathway. Interestingly the expressions of TH and DBH protein as well as the level of TH phosphorylation at Ser40, PKA, PKC and ERK1/2 substrates were higher in basal condition of the aged rats. However, contradicted findings were obtained in glucoprivic condition, which the protein expressions of DBH, pERK1/2 and substrates for pPKC were increased in young rats. Only substrate for pCDK was highly expressed in the old rats in the glucoprivic condition, while pPKC and pERK1/2 were decreased significantly. The results demonstrate that adrenal medulla of young and old rats are responsive to glucose deficit and capable to restore the blood glucose level by increasing the levels of blood catecholamines.
CONCLUSION: The present findings also suggest that, at least in rats, aging alters the protein expression of the biosynthetic catecholamine enzymes as well as protein kinase substrates that may attenuate the response to glucoprivation.

Matched MeSH terms: Deoxyglucose/pharmacology*