• Journal of Life Science
• /
• v.25 no.4
• /
• pp.456-462
• /
• 2015

We investigated the effects of fermented Sargassum thunbergii (FST) on platelet aggregation and serum lipid levels in rats made obese by a high fat diet. Six-week-old male SD-rats were randomly assigned to four groups as CON, HF-CON induced by high fat diet (HF), ST supplemented with HF (HFST100), and the fermented ST supplemented with HF group (HF-FST100). After 6 weeks, the results showed that the final weight and weight gain had decreased in the HF- FST100 group compared to the HF-CON group. Also, the food efficiency ratio was significantly reduced in the HF-FST100 group compared to HF-CON. The organ weights other than heart and spleen were significantly lower in the HF-FST100 group than in the HF-CON group. The levels of serum GOT and GPT significantly decreased in the HF-FST100 group over the HF-CON group. In addition, the total cholesterol, triglyceride and LDL-cholesterol levels were lower in the HF-FST100 group than in HF-CON, while the HDL-cholesterol level was higher in the HF-FST100. The ability of platelet aggregation of groups supplemented with FST was lower than the HF-CON group. These results suggest that FST may be beneficial in improving lipid profile and platelet aggregation in obesity.

• Development and Reproduction
• /
• v.13 no.4
• /
• pp.257-264
• /
• 2009

A neurotoxin, 6-hydroxydopamine (6-OHDA) has been widely used to create animal model for Parkinson's disease (PD) due to its specific toxicity against dopaminergic (DA) neurons. Since DA signals modulate a broad spectrum of CNS physiology, one can expect profound alterations in neuroendocrine activities of both PD patients and 6-OHDA treated animals. Limited applications of 6-OHDA injection model, however, have been made on the studies of hypothalamuspituitary neuroendocrine circuits. The present study was performed to examine whether blockade of brain catecholamine (CA) biosynthesis with 6-OHDA can make any alteration in the transcriptional activities of hypothalamus-pituitary hormone genes in adult male rats. Three-month-old male rats (SD strain) were received 6-OHDA ($200{\mu}g$ in $10{\mu}\ell$ of saline/animal) by intracerebroventricular (icv) injection, and sacrificed after two weeks. To determine the mRNA levels of hypothalamuspituitary hormone genes, total RNAs were extracted and applied to the semi-quantitative RT-PCRs. The mRNA levels of tyrosine hydroxylase (TH), the rate-limiting enzyme for the catecholamine biosynthesis, were significantly lower than those from the control group (control:6-OHDA=1:0.72${\pm}$0.02AU, p<0.001), confirming the efficacy of 6-OHDA injection. The mRNA levels of gonadotropin-releasing hormone (GnRH) and corticotropin releasing hormone (CRH) in the hypothalami from 6-OHDA group were significantly lower than those from the control group (GnRH, control:6-OHDA=1:0.39${\pm}$0.03AU, p<0.001; CRH, control:6-OHDA=1:0.76${\pm}$0.07AU, p<0.01). There were significant decreases in the mRNA levels of common alpha subunit of glycoprotein homones (Cg$\alpha$), LH beta subunit (LH-$\beta$), and FSH beta subunit (FSH-$\beta$) in pituitaries from 6-OHDA group compared to control values (Cg$\alpha$, control:6-OHDA=1:0.81${\pm}$0.02AU, p<0.001; LH-$\beta$, control:6-OHDA=1:0.68${\pm}$0.04AU, p<0.001; FSH-$\beta$, control:6-OHDA=1:0.84${\pm}$0.05AU, p<0.001). Similarly, the level of adrenocorticotrophic hormone (ACTH) transcripts from 6-OHDA group was significantly lower than that from the control group (control: 6-OHDA=1:0.86${\pm}$0.04AU, p<0.01). The present study demonstrated that centrally injected DA neurotoxin could downregulate the transcriptional activities of the two hypothalamus-pituitary neuroendocrine circuits, i.e., GnRH-gonadotropins and CRH-ACTH systems. These results suggested that hypothalamic CA input might affect on the activities of gonad and adrenal through modulation of hypothalamus-pituitary function, providing plausible explanation for frequent occurrence of sexual dysfunction and poor stress-response in PD patients.