Changes in calcium fluxes in mitochondria, microsomes, and plasma membrane vesicles of livers from monosodium L-glutamate-obese rats

The neurotherapeutic role of a selenium-functionalized quinoline in hypothalamic obese rats

RATIONALE

Obesity is considered one of the major global health problems and increases the risk of several medical complications, such as diabetes and mental illnesses.

OBJECTIVE

The present study investigated the effect of 7-chloro-4-(phenylselanyl) quinoline (4-PSQ) on obesity parameters, behavioral and neurochemical alterations in hypothalamic obese rats.

METHODS

Male Wistar rats received subcutaneous neonatal injections of monosodium glutamate (MSG, 4g/kg) or saline. After the Lee Index evaluation, rats were divided into groups and treated with 4-PSQ (5 mg/kg, intragastric route) or canola oil once a day (post-natal days (PND) 60→76). Open-field, elevated plus-maze, forced swim task, object recognition/location memory, and stepdown inhibitory avoidance tasks were conducted from PND 66 to 74. On PND 76, rats were euthanized and epididymal fat, blood, cerebral cortex, andhippocampus were removed. Blood biochemical parameters and cortical/hippocampal acetylcholinesterase (AChE) and Na /K -ATPase activities were assessed.

RESULTS

MSG increased the Lee Index characterizing the chemically induced hypothalamic obesity model. 4-PSQ reversed the increases of epididymal fat, blood glucose, and triglyceride levels caused by MSG exposure. 4-PSQ attenuated anxiety-like and depression-like behaviors induced by neonatal administrations of MSG. Memory deficits found in MSG-obese rats were reversed by treatment with 4-PSQ. Neurochemical alterations produced by MSG evidenced by stimulation ofNa⁺/K⁺-ATPase and AChE activities in the cerebral cortex and hippocampus of rats were normalized by 4-PSQ treatment.

CONCLUSIONS

In brief, 4-PSQ therapy improved hypothalamic obesity-related parameters, as well as psychiatric symptoms, cognitive impairment, and neurochemical alterations found in obese rats.

Monosodium glutamate induces memory and hepatic dysfunctions in mice: ameliorative role of Jobelyn® through the augmentation of cellular antioxidant defense machineries

This study investigated the effect of high doses of monosodium glutamate (MSG), a known food additive on hepatic, memory and locomotor functions in mice, and the ameliorative potentials of Jobelyn^® (JB), a unique dietary supplement. Twenty four  male Swiss mice  divided into 4 groups (n = 6) were given MSG (2, 4 and 8 g/kg) or normal saline (10 mL/kg) orally for 14 days. In the intervention study, another set of 30 male Swiss mice distributed into 5 groups (n = 6) received normal saline, MSG (8 g/kg) alone or in combination with JB (5, 10 and 20 mg/kg) orally, for 14 days. Memory and locomotor functions as well as brain oxido-nitrergic stress biomarkers were then assessed in both studies. The hepatic oxido-nitrergic stress biomarkers, liver enzymes functions and histomorphology of the liver were also assessed. MSG (2, 4 and 8 g/kg) produced memory dysfunction, hyperlocomotion, increased malondialdehyde and nitrite levels accompanied by decreased antioxidant status in the brain and hepatic tissues. MSG-treated mice had increased hepatic enzyme activities (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) and distorted cyto-architectural integrity of the liver. These findings further suggest that MSG compromised hepatic functioning, which might also contribute to its neurotoxicity. However, JB (5, 10 and 20 mg/kg, p.o) attenuated the memory deficit, hyperlocomotion, increased oxido-nitrergic stress responses in the brain and hepatic tissues induced by MSG (8 g/kg, p.o). JB also normalized hepatic enzymes activities and histomorphological changes in MSG-treated mice. Taken together, JB mitigated MSG-induced toxicity through mechanisms relating to enhancement of cellular antioxidant-machineries and normalization of hepatic enzymatic functions.