Biological Transport

Publication Title: 
BioFactors (Oxford, England)

The thiazolidinedione (TZDs) class of drugs are very effective for the treatment of type 2 diabetes mellitus (T2DM). But due to the adverse effects of synthetic TZDs, their use is strictly regulated. The therapeutic actions of TZDs are mediated via modulation of peroxisome proliferator-activated receptor gamma (PPAR?). Naturally occurring PPAR? modulators are more desirable as they lack the serious adverse effects caused by TZDs. This has prompted the exploitation of medicinal plants used in traditional medicine, for their potential PPAR? activity.

Author(s): 
Shyni, Gangadharan Leela
Kavitha, Sasidharan
Indu, Sasidharan
Arya, Anil Das
Anusree, Sasidharan Suseela
Vineetha, Vadavanath Prabhakaran
Vandana, Sankar
Sundaresan, Andikannu
Raghu, Kozhiparambil Gopalan
Publication Title: 
The Biochemical Journal

NaCT (sodium-coupled citrate transporter) is an Na(+)-coupled citrate transporter identified recently in mammals that mediates the cellular uptake of citrate. It is expressed predominantly in the liver. NaCT is structurally and functionally related to the product of the Indy (I'm not dead yet) gene in Drosophila, the dysfunction of which leads to lifespan extension. Here, we show that NaCT mediates the utilization of extracellular citrate for fat synthesis in human liver cells, and that the process is stimulated by lithium.

Author(s): 
Inoue, Katsuhisa
Zhuang, Lina
Maddox, Dennis M.
Smith, Sylvia B.
Ganapathy, Vadivel
Publication Title: 
Nature

Calorie restriction extends lifespan in organisms ranging from yeast to mammals. In yeast, the SIR2 gene mediates the life-extending effects of calorie restriction. Here we show that the mammalian SIR2 orthologue, Sirt1 (sirtuin 1), activates a critical component of calorie restriction in mammals; that is, fat mobilization in white adipocytes. Upon food withdrawal Sirt1 protein binds to and represses genes controlled by the fat regulator PPAR-gamma (peroxisome proliferator-activated receptor-gamma), including genes mediating fat storage.

Author(s): 
Picard, FrÈdÈric
Kurtev, Martin
Chung, Namjin
Topark-Ngarm, Acharawan
Senawong, Thanaset
Machado De Oliveira, Rita
Leid, Mark
McBurney, Michael W.
Guarente, Leonard
Publication Title: 
BMB reports

Autophagy, which is a process of self eating, has gained interest in the past decade due to its both beneficial and controversial roles in various biological phenomena. The discovery of autophagy genes (ATG) in yeast has led to focused research designed to elucidate the mechanism and regulation of this process. The role of autophagy in a variety of biological phenomena, including human disease, is still the subject of debate. However, recent findings suggest that autophagy is a highly regulated process with both beneficial and negative effects.

Author(s): 
Dwivedi, Meenakshi
Ahnn, Joohong
Publication Title: 
Journal of Ethnopharmacology

ETHNOPHARMACOLOGICAL RELEVANCE: Eucommia ulmoides Oliv. Bark. (EUE), has commonly been used to fortify the muscles and lungs, lower blood pressure, prevent miscarriage, improve the tone of liver and kidneys, and promote longevity the traditional tonic medicines of Korea, China, and Japan. AIM OF THE STUDY: In this study, we investigated that the neuroprotective activities and possible mechanisms of EUE aqueous extract in hydrogen peroxide (H(2)O(2))-induced neuronal cell death in human SH-SY5Y neuroblastoma cells.

Author(s): 
Kwon, Seung-Hwan
Kim, Min-Jung
Ma, Shi-Xun
You, In-Jee
Hwang, Ji-Young
Oh, Ji-Hwan
Kim, Sun-Yeou
Kim, Hyoung-Chun
Lee, Seok-Yong
Jang, Choon-Gon
Publication Title: 
Nature

Calorie restriction extends lifespan in organisms ranging from yeast to mammals. In yeast, the SIR2 gene mediates the life-extending effects of calorie restriction. Here we show that the mammalian SIR2 orthologue, Sirt1 (sirtuin 1), activates a critical component of calorie restriction in mammals; that is, fat mobilization in white adipocytes. Upon food withdrawal Sirt1 protein binds to and represses genes controlled by the fat regulator PPAR-gamma (peroxisome proliferator-activated receptor-gamma), including genes mediating fat storage.

Author(s): 
Picard, FrÈdÈric
Kurtev, Martin
Chung, Namjin
Topark-Ngarm, Acharawan
Senawong, Thanaset
Machado De Oliveira, Rita
Leid, Mark
McBurney, Michael W.
Guarente, Leonard
Publication Title: 
Nutrients

Recent studies have demonstrated that the intestine is a key target organ for overall health and longevity. Complementing these studies is the discovery of the trans-intestinal cholesterol efflux pathway and the emerging role of the intestine in reverse cholesterol transport. The surfacing dynamics of the regulation of cholesterol metabolism in the intestine provides an attractive platform for intestine-specific nutritional intervention strategies to lower blood cholesterol levels for protection against cardiovascular diseases.

Author(s): 
Wegner, Casey J.
Kim, Bohkyung
Lee, Jiyoung
Publication Title: 
Psychological Medicine

BACKGROUND: The evolutionary consequences of love are so important that there must be some long-established biological process regulating it. Recent findings suggest that the serotonin (5-HT) transporter might be linked to both neuroticism and sexual behaviour as well as to obsessive-compulsive disorder (OCD). The similarities between an overvalued idea, such as that typical of subjects in the early phase of a love relationship, and obsession, prompted us to explore the possibility that the two conditions might share alterations at the level of the 5-HT transporter.

Author(s): 
Marazziti, D.
Akiskal, H. S.
Rossi, A.
Cassano, G. B.
Publication Title: 
Ciba Foundation Symposium

Certain endogenous steroids are modulators of GABAA receptors. Tetrahydroprogesterone (THP, 5 alpha-pregnan-3 alpha-ol-20-one) and tetrahydrodeoxy-corticosterone (THDOC, 5 alpha-pregnane-3 alpha, 21-diol-20-one) behave as allosteric agonists of GABAA receptors whereas pregnenolone sulphate acts as an antagonist. THP and THDOC modulate ligand binding to GABAA receptors like barbiturates; they potentiate binding of the GABAA receptor agonist muscimol and the benzodiazepine flunitrazepam and they allosterically inhibit binding of the convulsant t-butylbicyclophosphorothionate.

Author(s): 
Majewska, M. D.
Publication Title: 
The Journal of Clinical Investigation

Plasmodium falciparum infecting hemoglobin (Hb)H and/or Hb Constant Spring erythrocytes has higher resistance to artemisinin in vitro than when infecting normal erythrocytes. This is due to low drug accumulation of infected erythrocytes resulting from competition with uninfected variant erythrocytes, which have a higher accumulation capacity than genetically normal cells. Drug accumulation of the parasite was shown to be saturable and dependent on metabolic energy.

Author(s): 
Kamchonwongpaisan, S.
Chandra-ngam, G.
Avery, M. A.
Yuthavong, Y.

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