Tag: mouse model

Brain atrophy in a murine model of chronic fatigue syndrome and beneficial effect of Hochu-ekki-to (TJ-41)

Abstract:

Brain-derived neurotrophic factor (BDNF) is associated with the main symptoms of chronic fatigue syndrome (CFS) and neuron apoptosis. Nevertheless, no study has been performed directly to explore the relationship between CFS, BDNF and neuron apoptosis.

We induced a CFS model by six injections of killed Brucella abortus antigen in BALB/c mice and treated them with Hochu-ekki-to (TJ-41). Daily running activity, body weight (BW), ratio of cerebral weight to BW (CW/BW) and expression levels of BDNF and Bcl-2 mRNA in the hippocampus were determined. The daily activity and CW/BW decreased significantly in the CFS model. BDNF and Bcl-2 mRNA expression levels in the hippocampus were suppressed in the CFS model and TJ-41 treated mice, while no significant difference was found between them.

We improved a murine model to investigate the relationship between CFS and brain dysfunction. In this model, reduced daily activity might have been associated with decreased hippocampal BDNF mRNA expression, hippocampal apoptosis and brain atrophy. TJ-41 increased the daily running activity of the model, which was independent of brain recovery.

 

Source: Chen R, Moriya J, Yamakawa J, Takahashi T, Li Q, Morimoto S, Iwai K, Sumino H, Yamaguchi N, Kanda T. Brain atrophy in a murine model of chronic fatigue syndrome and beneficial effect of Hochu-ekki-to (TJ-41). Neurochem Res. 2008 Sep;33(9):1759-67. doi: 10.1007/s11064-008-9620-1. Epub 2008 Mar 4. https://www.ncbi.nlm.nih.gov/pubmed/18317925

 

Beneficial effect of brewers’ yeast extract on daily activity in a murine model of chronic fatigue syndrome

Abstract:

The aim of this study was to assess the effect of Brewers’ yeast extract (BYE) on daily activity in a mouse model of chronic fatigue syndrome (CFS). CFS was induced by repeated injection of Brucella abortus (BA) antigen every 2 weeks. BYE was orally administered to mice in a dose of 2 g per kg per day for 2 weeks before injecting BA and for 4 weeks thereafter. We evaluated daily running activity in mice receiving BYE as compared with that in untreated mice.

Weekly variation of body weight (BW) and survival in both groups was monitored during the observation period. Spleen weight (SW), SW/BW ratio, percent splenic follicular area and expression levels of interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) mRNA in spleen were determined in both groups at the time of sacrifice. The daily activity during 2 weeks after the second BA injection was significantly higher in the treated group than in the control. There was no difference in BW between both groups through the experimental course. Two mice in the control died 2 and 7 days after the second injection, whereas no mice in the treated group died. Significantly decreased SW and SW/BW ratio were observed in the treated mice together with elevation of splenic follicular area.

There were suppressed IFN-gamma and IL-10 mRNA levels in spleens from the treated mice. Our results suggest that BYE might have a protective effect on the marked reduction in activity following repeated BA injection via normalization of host immune responses.

 

Source: Takahashi T, Yu F, Zhu SJ, Moriya J, Sumino H, Morimoto S, Yamaguchi N, Kanda T. Beneficial effect of brewers’ yeast extract on daily activity in a murine model of chronic fatigue syndrome. Evid Based Complement Alternat Med. 2006 Mar;3(1):109-15. Epub 2006 Jan 23. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1375235/ (Full article)

 

Green tea extract and catechin ameliorate chronic fatigue-induced oxidative stress in mice

Abstract:

Chronic fatigue syndrome (CFS) is an illness characterized by persistent and relapsing fatigue, often accompanied by numerous symptoms involving various body systems. The etiology of CFS remains unclear, but a number of studies have shown that oxidative stress may be involved in its pathogenesis. The present study was designed to investigate the protective effect of green tea extract (GTE) and catechin in the mouse model of CFS.

Animals were subjected to a forced swimming test session of 6 minutes every day for 7 days; a significant increase in immobility time on successive days represented the CFS in mice. Biochemical analysis revealed that the chronic swim test significantly increased lipid peroxidation levels and decreased glutathione levels in mouse whole-brain homogenate.

Treatment with GTE (25 or 50 mg/kg, i.p.) and catechin (50 or 100 mg/kg, i.p.) for 7 days reversed the increase in immobility time. Protection was correlated with the lowered levels of lipid peroxidation and restoration of reduced glutathione levels in the brains of fatigued mice. These findings strongly suggest the pivotal role of oxidative stress in the pathophysiology of CFS and that GTE and catechin could be used as potential agents in the management of CFS and warrant the inclusion of GTE and catechin in the treatment regimen of CFS patients.

 

Source: Singal A, Kaur S, Tirkey N, Chopra K. Green tea extract and catechin ameliorate chronic fatigue-induced oxidative stress in mice. J Med Food. 2005 Spring;8(1):47-52. http://www.ncbi.nlm.nih.gov/pubmed/15857209

 

Effect of Hochu-ekki-to (TJ-41), a Japanese Herbal Medicine, on Daily Activity in a Murine Model of Chronic Fatigue Syndrome

Abstract:

We aimed to evaluate the effect of a Japanese herbal medicine, Hochu-ekki-to (TJ-41), on daily activity in a murine model of chronic fatigue syndrome (CFS).

CFS was induced by repeated injection of Brucella abortus (BA) antigen every 2 weeks. TJ-41 was orally administered to mice in a dose of 500 mg/kg/day for 1 week before injecting BA and for 4 weeks thereafter. We evaluated daily running activity in mice receiving TJ-41 as compared with that in untreated mice. Survival of both mouse groups was also monitored during the observation period. Body weight (BW), spleen weight (SW), SW/ BW ratio and expression levels of interleukin-10 (IL-10) mRNA in spleen were determined in both groups at the time of sacrifice.

The daily activity was significantly higher in the treated group than in the control. Two mice in the untreated group died 2 days after the second injection of BA, whereas no mice in the group treated with TJ-41 died. The SW and SW/BW ratio were significantly lower in the treated mice than in the control. Suppressed IL-10 mRNA levels were observed in the spleens of the mice treated with TJ-41. Our data suggest that Hochu-ekki-to might possess an inhibitory effect on the marked decrease in running activity following BA injection.

 

Source: Wang XQ, Takahashi T, Zhu SJ, Moriya J, Saegusa S, Yamakawa J, Kusaka K, Itoh T, Kanda T. Effect of Hochu-ekki-to (TJ-41), a Japanese Herbal Medicine, on Daily Activity in a Murine Model of Chronic Fatigue Syndrome. Evid Based Complement Alternat Med. 2004 Sep 1;1(2):203-206. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC516453/ (Full article)

 

Role of antioxidants in chronic fatigue syndrome in mice

Abstract:

The present study was carried out using mice model of chronic fatigue syndrome (CFS) in which mice were forced to swim everyday for 7 days for a 6 min session. There was a significant increase in despair behavior (immobility period) in saline treated mice on successive days.

Treatment with potent antioxidants carvedilol (5 mg/kg, i.p.) and melatonin (10 mg/kg, i.p.) produced a significant reduction in immobility period. Similar results were observed with herbal products St. John’s Wort (Hypericum perforatum L) (10 mg/kg, p.o.) and GS-02 (20 mg/kg, p.o.). Fluoxetine, a selective serotonin reuptake inhibitor produced a significant effect only on first and second day of its treatment.

Biochemical analysis revealed that chronic swim test significantly increased lipid peroxidation and catalase levels in whole brains of mice. There was a decrease in the levels of super oxide dismutase (SOD) and glutathione reductase (GSH) in the brain.

Administration of carvedilol, melatonin, GS-02 and St. John’s Wort restored the levels of lipid peroxidation and glutathione. The enzymes SOD and catalase were also restored. Fluoxetine affected the biochemical variables not to the same extent as other treatments. The findings of the present study suggest that oxidative stress might play a significant role in the pathophysiology of CFS. Thus antioxidants and herbal products like St. Johns wort and GS-02 could be useful in the treatment of CFS.

 

Source: Singh A, Garg V, Gupta S, Kulkarni SK. Role of antioxidants in chronic fatigue syndrome in mice. Indian J Exp Biol. 2002 Nov;40(11):1240-4. http://www.ncbi.nlm.nih.gov/pubmed/13677625

 

Mouse running activity is lowered by Brucella abortus treatment: a potential model to study chronic fatigue

Abstract:

Chronic fatigue syndrome, which can occur after acute infection and last for years, is characterized by severe and persistent fatigue. Others have reported decreases in mouse running activity following infection and have suggested this may provide an animal model for studying chronic fatigue.

Voluntary running is a highly motivated activity in mice, which will often run 5-7 mi/day in our laboratory. Following 2 weeks of acclimation to running wheels with food and water available ad lib, female BALB/c mice received 0.2-mL tail vein injections of killed Brucella abortus (BA) or saline vehicle. Subsequently the effects on voluntary running and grooming behavior were determined.

Injection of BA caused an immediate large decrease in running and a lack of grooming. Vehicle injections produced no changes in behavior. After the first several days of reduced running behavior, levels of running and grooming slowly returned back to normal over the next 2-4 weeks, with substantial individual differences in the rate of recovery.

The pattern of running during recovery was intriguing in that BA mice first ran at normal levels just after the lights went out, but they stopped after only 1-2 h. As recovery proceeded, they gradually increased the duration of the running bout during the night. Because this model uses voluntary exertion and the ability to run for longer periods of time characterizes recovery, the model may be a good one for studying the biologic underpinnings of chronic fatigue.

 

Source: Ottenweller JE, Natelson BH, Gause WC, Carroll KK, Beldowicz D, Zhou XD, LaManca JJ. Mouse running activity is lowered by Brucella abortus treatment: a potential model to study chronic fatigue. Physiol Behav. 1998 Mar;63(5):795-801. http://www.ncbi.nlm.nih.gov/pubmed/9618001