Inhibition of FASN reduces the synthesis of medium-chain fatty acids in goat mammary gland.

Fatty acid synthase (FASN) is known as a crucial enzyme of cellular de novo fatty acid synthesis in mammary gland which has been proved as the main source of short and medium-chain fatty acids of milk. However, the regulatory role of FASN in goat-specific milk fatty acids composition remains unclear. We cloned and analyzed the full-length of FASN gene from the mammary gland of Capra hircus (Xinong Saanen dairy goat) (DQ 915966). Comparative gene expression analysis suggested that FASN is predominantly expressed in fat, small intestine and mammary gland tissues, and expresses higher level at lactation period. Inhibition of FASN activity by different concentrations (0, 5, 15, 25 and 35 µM) of orlistat, a natural inhibitor of FASN, resulted in decreased expression of acetyl-CoA carboxylase α (ACCα), lipoprotein lipase and heart-type fatty acid binding protein (H-FABP) in a concentration-dependent manner in goat mammary gland epithelial cells (GMEC). Similar results were also obtained by silencing of FASN. Additionally, reduction of FASN expression also led to apparent decline of the relative content of decanoic acid (C10:0) and lauric acid (C12:0) in GMEC. Our study provides a direct evidence for inhibition of FASN reduces cellular medium-chain fatty acids synthesis in GMEC.

Electromagnetic thermotherapy using fine needles for hepatoma treatment.

BACKGROUND AND AIMS: Hepatocellular carcinoma can be treated with heat-based therapies, especially radiofrequency ablation (RFA). However, RFA has limited efficacy and is quite expensive. We designed a new system using fine needles combined with an alternating magnetic field to generate hyperthermia for the treatment of hepatocellular carcinoma in a rat hepatoma model. Our aims are to assess the efficacy of our method and determine survival up to 30 days. METHODS: An N1-S1 cell line was inoculated into the livers of Sprague-Dawley rats, generating tumors after 14 days. The animals were randomized into 5 groups and treated after laparotomy either with normal saline (group I), iron oxide nanoparticles (group II), fine needles (group III), fine needles and iron oxide nanoparticles combined (group IV) or self-designed two-part needles placed under ultrasonographic guidance percutaneously (group V). Every rat was placed in an alternating magnetic field. The temperature in the treatment area was maintained between 55 and 60 °C. At day 30 after treatment, tumor volumes and mortality were assessed and histology samples were studied. RESULTS: Tumor volumes were significantly reduced and survival rate was prolonged in groups III, IV and V versus groups I and II (P < 0.05). On pathological examination, groups III, IV and V presented obvious necrosis, apoptosis, calcifications and inflammatory changes in the treatment area. CONCLUSION: Our study demonstrates that hyperthermia generated by fine stainless-steel needles combined with an alternating magnetic field effectively inhibits hepatoma growth in rats and prolongs their survival. Further, this method can be applied percutaneously under ultrasonographic guidance.

Localised heating of tumours utilising injectable magnetic nanoparticles for hyperthermia cancer therapy.

This study reports an investigation of hyperthermia cancer therapy utilising an alternating magnetic field to induce a localised temperature increase on tumours by using injectable magnetic nanoparticles. In-vitro and in-vivo experiments represent the feasibility of hyperthermia cancer therapy. A feedback temperature control system was first developed to keep the nanoparticles at a constant temperature to prevent overheating in the tumours such that a safer and more precise cancer therapy becomes feasible. By using the feedback temperature control system, magnetic nanoparticles can be heated up to the specific constant temperatures, 37, 40, 42, 45, 46 and 47 degrees C, respectively, with a variation less than 0.2 degrees C. With this approach, the in-vitro survival rate of tumour cells at different temperatures can be systematically explored. It was experimentally found that the survival rate of cancer cells can be greatly reduced while CT-26 cancer cells were heated above 45 degrees C. Besides, localised temperatures increase as high as 59.5 degrees C can be successfully generated in rat livers by using the proposed method. Finally, complete regression of tumour was achieved. The developed method used injectable magnetic nanoparticles and may provide a promising approach for hyperthermia cancer therapy.

Protective effect of melatonin on renal injury of rats induced by bile duct ligation.

Oxygen radicals have been implicated in the pathogenesis of renal injury induced by extrahepatic cholestasis. We conduct this study to investigate whether melatonin can have a protective effect against such injury. Either normal saline or gentamicin with or without melatonin was injected into rats that received either a bile duct ligation or a sham operation. The serum levels of malondialdehyde and total antioxidative activity were measured. The kidney was fixed for histologic scoring of renal injury. The serum malondialdehyde level was highest in the rats that received both bile duct ligation and gentamicin injection. Treatment with melatonin significantly increased the serum total antioxidative activity and reduced the serum malondialdehyde concentration. The mean score of renal injury, highest in the rats receiving bile duct ligation and gentamicin injection, was significantly reduced with melatonin treatment. By reducing the systemic oxygen radicals, supplementation with antioxidants exerts a protective effect on the renal injury induced by extrahepatic cholestasis.

Electrochemical therapy--comparison with other local treatment methods on rat model.

BACKGROUND/AIMS: Electrochemical therapy is an alternative to treat hepatoma. We compare this method with the other local injection methods on rat liver. METHODOLOGY: Five groups of Wister rats (24 in each) were anaesthetized. Electrochemical therapy was set under direct current, 6 volts, electrodes were 0.5 cm apart, 0.5 cm deep into exposed parenchyma for 10 min. Local injection was done with 50 microL of 95% alcohol, 30 microL of 20% acetic acid, 30 microL of 35% hydrochloric acid, and 30 microL of 20% sodium hydroxide via a 27-gauge needle under direct vision into each rat. Rats and their livers were examined postmortem on day 1, 3, 7 and 14. RESULTS: In electrochemical therapy, the treated area showed coagulation necrosis and without blood cells on day 1; then the margin became blurred. Mononuclear cell infiltration, reperfusion and fibrous band formation were prominent from day 3 through day 14. In local injection groups, the necrosis is quite irregular and unpredictable. The regeneration went under similar process. CONCLUSIONS: To destroy tissue locally, electrochemical therapy is unique for its predictability in destructive area and the recovery process and is as effective as the other injection methods. Therefore, it has great potential for hepatoma treatment.

In vitro and in vivo studies for modified ethyl cyanoacrylate regimens for sclerotherapy.

Cyanoacrylates have known for their ability to polymerize rapidly in the presence of traces of weakly basic moieties such as water. The tissue adhesive, Histoacryl(R) (N-butyl 2-cyanoacrylate), has been reported to control bleeding through endoscopic sclerotherapy. But the commercially available Histoacryl(R) is expensive, and it has the problem like other cyanoacrylates that the glue tends to flow/run away from the point of application, which is inherent to the low viscosity, making precise application difficult. In this study, ethyl cyanoacrylate (ECA), the main constituent of "super glue," was employed instead of Histoacryl(R) due to its lower cost. The aim of the research is to modify the compositions of ECA regimen and evaluate its feasibility for sclerosant application through both in vitro flow circuit model and in vivo animal tests. It was noted that the difference in the relative hardening rate between the in vitro Hepes-Tyrodes buffer flowing model and the in vivo rat model for the ECA and Histoacryl(R) was related to the existence of the blood protein, such as albumin, in the physiological milieu. It was also noticed that the ECA setting rate was greatly increased either in Hepes-Tyrodes buffer or in blood (to a comparable rate as Histoacryl(R) in vivo) by adding a few doses of caffeine, which acts as a polymerization initiator. This would lead to far better injection precision during sclerotherapy. Furthermore, in vivo histological examination for the occluded lumen of the rat's inferior vena cava and a clinical piglet portal vein occlusion experiment have suggested this new sclerosant regimen, caffeine/ECA, is of great promise in endoscopic sclerotherapy.

Saturated saline enhances the effect of electrochemical therapy.

We conducted this experiment to assess the effect of saline injection in electrochemical therapy. Platinum electrodes using direct current were inserted into egg white or liver parenchyma. Pure water or 0.9%, 3%, or 26% sodium chloride were injected into various objects to compare with the control group (no injection). Power was set at 10 V. In the egg-white experiment, gas bubbles and coagulated protein developed around the electrodes. In ex vivo liver, frothy reddish debris developed around the cathodes, while a hardening and shrunken surface occurred around the anodes. The pH was 14 around the cathodes, 0 around the anodes. The electric current, the amount of coagulated protein, and the severity of tissue damage were all in proportion to the concentrations of the injected saline. The volume destroyed in the 26% saline group was 8.1 times larger than that of the control group. Therefore, injected saline, especially saturated saline, can enhance the effect of electrochemical therapy.

[Effects of emodin, sennosides and rheum polysaccharides on free calcium in isolated rat liver cells].

The effects of emodin (EMD), sennosides (SEN) and Rheum polysaccharides (RPP) on the free calcium level in the isolated rat liver cells were studied with Ca2+ level 131.60 +/- 37.79 nmol/L in the liver cells. After adding CaCl2 (2 mmol/L) and KCl (120 mmol/L) to liver cell suspension sequentially, the free Ca2+ levels were significantly elevated compared with that of the resting status (P < 0.01). When the liver cells were pretreated with EMD (0.037 mmol/L) for 10 min, in the resting status or using the above doses of CaCl2 and KCl, the free Ca2+ levels were significantly increased compared with that of the control groups (P < 0.01). On the contrary, after administration of SEN (0.046-0.092 mmol/L) and RPP (0.1-0.2 mg/ml), the free Ca2+ levels were obviously decreased compared with that of the control groups (P < 0.01). Furthermore, the inhibitory effect was dose dependent. The opposite effects of the different active ingredients of rhubarb (EMD,SEN,RPP) on the free Ca2+ levels suggested that rhubarb has many kinds of regulatory function in the liver cells.

Toxic effects of cholelitholytic solvents on gallbladder and liver. A piglet model study.

We evaluated the toxic effects of four currently used chemolytic solvents--dimethyl sulfoxide (DMSO, 99%), ethyl propionate (EP, 99%), tetrasodium ethyl-dimethyl tetraacetate (4Na-EDTA, 2%, pH 11), and methyl tert-butyl ether (MTBE, purity = 99.5%) in an animal model. Each solvent was tested in nine farm piglets (Landrace), weighing between 20 and 25 kg. A solvent-resistant catheter was inserted transhepatically into the gallbladder (GB) using sonographic guidance 24 hr prior to each experiment. Seventy-five milliliters of each solvent was infused over 3 hr into the gallbladder. The following day, a laparotomy was performed in order to assess for possible damage to the liver, GB, bile ducts (BD), or intestines. The GB and liver were resected and their histology examined. The following pathologic grades were assigned to GB, BD, and liver specimens to describe the tissue damage: normal (0), mild (1), moderate (2), and severe (3). We found that DMSO had the highest score on gallbladder and bile duct injury (49, 3), followed by EP (36, 2), EDTA (14, 1) and MTBE (16, 0), respectively; the difference in gallbladder damage was statistically significant. Very mild hepatocyte damage was present in the DMSO (2) and MTBE (2) groups. The administration of EP and EDTA resulted in no liver injury at all. Piglets within each treatment group suffered from varying degrees of tissue injury. No deaths were attributed to the administered solvents. We concluded that DMSO, EP, EDTA, and MTBE do not have serious local toxic effect on the GB, BD, and intestine; nor do they lead to severe hepatotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of sennosides, rhubarb polysaccharides and emodin on the cytoplasmic free calcium in isolated rat brain cells].

Free intracellular Ca2+ ([Ca2+]i) levels in rat brain were measured by Ca(2+)-sensitive fluorescent indicator Fura-2/Am and the effects of sennoside (SEN), polysaccharides from Rheum palmatum (RPP) and emodin (EMD) were studied. Results showed that the resting [Ca2+]i level in the brain cells was 176.25 +/- 44.67 nmol.L-1 (n = 10) in Ca(2+)-free Hank's solution containing EGTA 0.5 mmol.L-1. After adding CaCl2 (2 mmol.L-1) and KCl (120 mmol.L-1) to the brain cells suspension sequentially, the free [Ca2+]i levels were obviously elevated (P < 0.01) compared with that of resting level. The brain cells were pretreated with SEN (0.07, 0.37 mmol.L-1) for 10 min. In the resting or using the above doses of CaCl2 and KCl, the [Ca2+]i were obviously decreased compared with the control groups (P < 0.01) at the same conditions. RPP dose-dependently decreased the [Ca2+]i. On the contrary, when brain cells were pretreated with EMD (0.037 mmol.L-1) for 10 min, the [Ca2+]i were obviously increased compared with the control groups (P < 0.01) at the same conditions. The results showed that EMD could not only promote the release of intracellular Ca2+ but also the influx of extracellular Ca2+. The opposite effects of the different active components of rhubarb on the [Ca2+]i levels suggest that rhubarb may have different kinds of regulatory functions on brain cells.

[Study on effect of emodin on the isolated intestinal smooth muscle of guinea-pigs].

Emodin is an active principle of Rheum palmatum. It is reported that emodin possesses antibiotic and antineoplastic functions. The effect of emodin action on the isolated intestinal smooth muscle of guinea-pigs were dose dependent. When the dose of emodin was less than 29.6 mumol/L, the contraction effect enhanced obviously with increasing dosage; but whenever the dose increased to more than 29.6 mumol/L, on the contrary, the effect decreased gradually and ceased finally. Emodin with appropriate concentration (14.8 mumol/L) strengthened the effect of acetylcholine (Ach) on the isolated ileum and large intestine of guinea-pigs (P < 0.05 and P < 0.01). But high concentration of emodin could reduce even completely antagonize the effect of Ach. Under such condition, CaCl2 could restore the effect of Ach on the smooth muscle. It is suggested that emodin has biphasic regulatory effect on the intestinal smooth muscle, and its effect is related to calcium ion.

[Prophylactic and therapeutic effect of jiawei zhigancao tang injection on experimental arrhythmia in rats].

The antiarrhythmic effect of Jiawei Zhigancao Tang injection (JZTI) was studied in experimental arrhythmia induced by aconitine or by CaCl2 in anesthetized rats. The prophylactic dose of JZTI (5g/kg, i.v.) reduced the incidence rate of premature ventricular complexes, ventricular tachycardia (P < 0.01), delayed the onset time of arrhythmia induced by CaCl2 (P < 0.01), and the recovery time of sinus rhythm occurred earlier than that of control group (P < 0.01). The therapeutic dose of JZTI (10g/kg, i.v.) raised the rate of aconitine-induced arrhythmia to sinus rhythm conversion (P < 0.05). The results showed that JZTI could significantly antagonize arrhythmia induced by aconitine or by Cacl2 in rats.