Jung-Ok Kim

Expression of brain-derived neurotrophic factor in rat dorsal root ganglia, spinal cord and gracile nuclei in experimental models of neuropathic pain

Chronic constriction injury of the sciatic nerve and lumbar L5 and L6 spinal nerve ligation provide animal models for pain syndromes accompanying peripheral nerve injury and disease. In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat L4 and L5 dorsal root ganglia (DRG) and areas where afferents from the DRG terminates (the L4/5 spinal cord and gracile nuclei) in these experimental models of neuropathic pain. Chronic constriction injury induced significant increase in the percentage of small, medium and large BDNF-immunoreactive neurons in the ipsilateral L4 and L5 DRG. Following spinal nerve ligation, the percentage of large BDNF-immunoreactive neurons increased significantly, and that of small BDNF-immunoreactive neurons decreased markedly in the ipsilateral L5 DRG, while that of BDNF-immunoreactive L4 DRG neurons of all sizes showed marked increase. Both chronic constriction injury and spinal nerve ligation induced significant increase in the number of BDNF-immunoreactive axonal fibers in the superficial and deeper laminae of the L4/5 dorsal horn and the gracile nuclei on the ipsilateral side. Considering that BDNF may modulate nociceptive sensory inputs and that injection of antiserum to BDNF significantly reduces the sympathetic sprouting in the DRG and allodynic response following sciatic nerve injury, our results also may suggest that endogenous BDNF plays an important role in the induction of neuropathic pain after chronic constriction injury and spinal nerve ligation. In addition, the increase of BDNF in L4 DRG may contribute to evoked pain which is known to be mediated by input from intact afferent from L4 DRG following L5 and L6 spinal nerve ligation.

Antihyperglycemic and Antioxidative Effects of New Herbal Formula in Streptozotocin-Induced Diabetic Rats

Herbal prescriptions have been recognized as potentially valid by the scientific medical establishment, and their use has been increasing. The present study investigated the antidiabetic effects of a new herbal formula (NHF) consisting of Polygonati Rhizoma, Rehmanniae Radix, Salviae Miltiorrhizae Radix, Puerariae Radix, Schizandrae Fructus, and Glycyrrhizae Radix. Streptozotocin-induced diabetic rats were orally administered NHF (300 mg/kg of body weight/day) for 4 weeks. The diabetic rats exhibited hyperglycemia, increased food and water intake, loss of body weight gain, elevated hepatic thiobarbituric acid-reactive substances (TBARS), and decreased activities of hepatic antioxidant enzymes (such as superoxide dismutase [SOD], catalase [CAT], and glutathione peroxidase [GSH-Px]), level of mRNA of glucose transporter (GLUT) 4 in soleus muscle, and numbers of insulin-positive cells and the size of beta-cells in pancreas. Administration of NHF significantly decreased the blood glucose level and the food and water intake and considerably increased the body weights of diabetic rats. Also, NHF treatment significantly increased plasma insulin levels and the number and size of insulin-immunoreactive cells in the pancreas of diabetic rats. Administration of NHF significantly lowered the levels of TBARS and increased the activities of SOD, CAT, and GSH-Px in the liver of diabetic rats. In addition, treatment with NHF increased the mRNA levels of GLUT4 in soleus muscle. Therefore NHF may be an effective preventive and therapeutic agent for diabetes mellitus.

Expression of brain-derived neurotrophic factor in catecholaminergic neurons of the rat lower brainstem after colchicine treatment or hemorrhage

Widespread brain-derived neurotrophic factor messenger RNA expression has been detected in the region of catecholamine groups of the rat lower brainstem, while few brain-derived neurotrophic factor-immunoreactive cells were found in this area. In the present study, a double-color immunofluorescence technique for brain-derived neurotrophic factor and tyrosine hydroxylase after colchicine treatment was employed to evaluate the possible presence of brain-derived neurotrophic factor immunoreactivity in the catecholaminergic cells of the rat lower brainstem. We detected many new brain-derived neurotrophic factor-immunoreactive cells in the A1, A2, A4, A6-A10 and C1-C3 cell groups and in the other lower brainstem nuclei where, without colchicine treatment, brain-derived neurotrophic factor messenger RNA was expressed, but not brain-derived neurotrophic factor immunoreactivity. In addition, the catecholaminergic neurons were found to express brain-derived neurotrophic factor immunoreactivity with the co-existence being greatest, in percentage terms, in medullary catecholaminergic cell groups. Hypotensive hemorrhage, which activates medullary catecholaminergic neurons, induced the expression of brain-derived neurotrophic factor immunoreactivity in catecholaminergic neurons (A1/C1 and C2). The results demonstrate that brain-derived neurotrophic factor is regulated by neuronal activity in medullary catecholaminergic cell groups involved in central cardiovascular regulation.

Growth-inhibitory effects of a Bulnesia sarmienti aqueous extract on A549 Cells in vitro and S180 cells in vivo

The effects of Bulnesia sarmienti (BS) aqueous extract on the cell growth of A549 cell lines were investigated. BS has strong cytotoxic activity on the A549 cell lines (IC50; less than 100 μ g/mL) in MTT assay. HPLC confirmed that BS contains catechins as major compound. Cell cycle analysis by flow cytometry indicated that BS arrested the cell cycle in the sub-G1 phase. BS induced DNA fragmentation, and increased the expression of the p53 protein in immunoblot analysis. These results indicated that the anticancer effect of BS was mediated via the process of apoptosis and growth-inhibition.

Effect of Bulnesia sarmienti Water Extract on Lipid Metabolism in Type-1 Diabetic Rats.

The effects of Bulnesia sarmienti water extract on lipid metabolism were investigated in type-1 diabetes rats. The rats were fed a basal diet and B. sarmienti water extract for 8 weeks. The rats were randomly assigned to each treatment group: normal, control, three kinds of treatment group (BWO: 0.45 mg/ml, BW1: 0.9 mg/ml, BW2: 1.8 mg/ml). After 8 weeks of experimental diets consumption, the body weights and food efficiency ratio of B. sarmienti water extract fed groups were not change with those in the control group. The concentration in plasma total-cholesterol, LDL-cholesterol, triglyceride were significantly decrease in the B. sarmienti water extract groups compared with those in the control group. Although it was not possible to observe blood glucose control effects of eight weeks of B. sarmienti water extract feeds in type-1 diabetes model, it was discovered that the feeds are highly effective in lowering the levels of blood lipid substances triglycerides, total-cholesterol, and LDL-cholesterol.

Effect of Bulnesia sarmienti Water Extracts on Lipid Metabolism in Neonatally Streptozotocin- Induced Diabetic Rats.

The effects of Bulnesia sarmienti water extract on lipid metabolism were investigated in type-2 diabetes rats. The rats were fed a basal diet and B. sarmienti water extract for 8 weeks. The rats were randomly assigned to each treatment group : normal, control, two kinds of treatment group (BW1: 0.9 mg/ml, BW2: 1.8 mg/ml). After 8 weeks of experimental diets consumption, the body weights and food efficiency ratio of B. sarmienti water extract fed groups were not different from those in the control group. The concentrations of total-cholesterol, LDL-cholesterol, and triglyceride in blood plasma were significantly decreased in the B. sarmienti water extract groups comparison to the control group. Although blood glucose control effects were not observed, the B. sarmienti water extract feeds were highly effective in lowering the levels of blood lipid substances such as triglycerides, total-cholesterol, and LDL-cholesterol.