Neonatal administration of monosodium glutamate prevents the development of ethanol- but not psychostimulant-induced sensitization: a putative role of the arcuate nucleus

Acute unilateral nephrectomy (AUN) results in natriuresis from the remaining kidney through reflex pathways involving the central nervous system and requiring an intact pituitary gland. The natriuresis is accompanied by an increase in the plasma concentration of a peptide or peptides derived from the N-terminal fragment (NTF) of proopiomelanocortin. We measured plasma immunoreactive NTF-like material (IR-NTF) before and after AUN in control rats and rats treated neonatally with monosodium glutamate (MSG), a procedure that produces neuroendocrine dysfunction by destroying cell bodies in the hypothalamic arcuate nucleus, median eminence, and other brain regions. In control rats, IR-NTF increased from 85.8 +/- 54.9 (SD) to 207 +/- 98.1 fmol/ml after AUN (P less than 0.02) as sodium excretion (UNaV) doubled. In MSG-treated rats, AUN produced no change in plasma IR-NTF concentration (58.8 +/- 21.3 vs. 68.3 +/- 18.5 fmol/ml (P = NS), nor did UNaV increase. Tissue content of IR-NTF was reduced in the arcuate nucleus and anterior lobe of pituitaries from MSG-treated rats compared with controls, but was no different in the neurointermediate lobe. These results indicate that the hypothalamic lesion produced by neonatal administration of MSG prevents both the increase in plasma IR-NTF concentration and the natriuresis after AUN, and therefore lend further support to the concept of a causal relationship between these two consequences of AUN.

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Attenuation of leptin-mediated effects by monosodium glutamate-induced arcuate nucleus damage

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1997.273.1.e202 ◽

1997 ◽

Vol 273 (1) ◽

pp. E202-E206 ◽

Cited By ~ 19

Author(s):

R. Dawson ◽

M. A. Pelleymounter ◽

W. J. Millard ◽

S. Liu ◽

B. Eppler

Keyword(s):

Weight Gain ◽

Arcuate Nucleus ◽

Body Weight Gain ◽

Monosodium Glutamate ◽

Anatomic Site ◽

Leptin Receptors ◽

Fat Depots ◽

Mediated Effects ◽

Night Feeding ◽

Neonatal Administration

Leptin is a protein secreted by adipocytes that is important in regulating appetite and adiposity. Recent studies have suggested the presence of leptin receptors in the arcuate nucleus of the hypothalamus (ANH). Neonatal administration of monosodium glutamate (MSG) damages the ANH, resulting in obesity and neuroendocrine dysfunction. Neonatal administration of MSG was utilized to test the hypothesis that the anatomic site for many of leptin's actions is the ANH. Female control (n = 6) and MSG-treated rats (n = 7) were implanted for 14 days with osmotic minipumps containing phosphate-buffered saline or leptin (1 mg.kg-1.day-1). Leptin suppressed (P < 0.05) body weight gain in controls but did not suppress weight gain in MSG-treated rats. Leptin decreased (P < 0.05) fat depots in controls but had no effect in MSG-treated rats. Night feeding was suppressed (P < 0.05) in leptin-treated control rats. MSG-treated rats showed a suppression in food intake that was of a smaller magnitude and appeared later in the course of leptin treatment. These findings suggest that leptin mediates some physiological actions related to fat mobilization via receptors located in the ANH.

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Putative role of Lateral Habenula projections to Dorsal Raphe Nucleus in encoding for depression-like behaviour and abnormal circadian rhythms.

10.26226/morressier.5b31ec482afeeb001345b44a ◽

2018 ◽

Author(s):

Dipesh Chaudhury ◽

He Liu

Keyword(s):

Circadian Rhythms ◽

Dorsal Raphe Nucleus ◽

Dorsal Raphe ◽

Raphe Nucleus ◽

Lateral Habenula ◽

Putative Role ◽

Dorsal Raphé

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Monosodium Glutamate Toxicity and the Possible Protective Role of L–Carnitine

Science & Technology Journal ◽

10.22232/stj.2018.06.01.06 ◽

2018 ◽

Vol 6 (1) ◽

pp. 45-56

Author(s):

Lalrinzuali Sailo ◽

◽

Meesala Krishna Murthy ◽

Khandayataray Pratima ◽

Vikas Kumar Roy ◽

...

Keyword(s):

Human Subjects ◽

Monosodium Glutamate ◽

Essential Amino Acids ◽

Protective Role ◽

Glutamate Toxicity ◽

Common Salt ◽

Genotoxic Effects ◽

Naturally Occurring ◽

Flavour Enhancer

Monosodium glutamate is naturally available non-essential amino acids, which found in naturally occurring foods and used as flavour enhancer worldwide. Monosodium glutamate is believed to be linked with diverse health problems. The aim of the study was toxic effects of monosodium glutamate (MSG) and the protective role of L-carnitine, light on the available literature from last 25 years about diverse toxicity studies which had been carried out on animal and human models. Google scholar, NCBI, PUBMED, EMBASE, Wangfang databases, and Web of Science databases were used to retrieve the available studies. MSG was linked with deleterious effects particularly in animals including induction of obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects showed in Literature. Few reports revealed increased hunger, food intake, and obesity in human subjects due to MSG consumption. Hepatotoxic, neurotoxic, and genotoxic effects of monosodium glutamate on humans carried out very limitedly. High consumption of monosodium glutamate may be linked with harmful health effects showed in available literatures. So, it is recommended to use common salt instead of MSG. Furthermore, intensive research is required to explore monosodium glutamate–related molecular and metabolic mechanisms. L-carnitine can protect from Hepatotoxic, neurotoxic, renal impairment and genotoxic effects functionally, biochemically and histopathologically with a corresponding reduction of oxidative stress.

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Importance of Apolipoprotein A-I and A-II Composition in HDL and Its Potential for Studying COVID-19 and SARS-CoV-2

Medicines ◽

10.3390/medicines8070038 ◽

2021 ◽

Vol 8 (7) ◽

pp. 38

Author(s):

Kyung-Hyun Cho

Keyword(s):

Antiviral Activity ◽

High Density ◽

High Density Lipoproteins ◽

Potent Antiviral Activity ◽

Apolipoprotein A ◽

Putative Role

The composition and properties of apolipoprotein (apo) A-I and apoA-II in high-density lipoproteins (HDL) might be critical to SARS-CoV-2 infection via SR-BI and antiviral activity against COVID-19. HDL containing native apoA-I showed potent antiviral activity, while HDL containing glycated apoA-I or other apolipoproteins did not. However, there has been no report to elucidate the putative role of apoA-II in the antiviral activity of HDL.

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