Exploring the causal relationship between interleukin-6 or C reactive protein and malignant melanoma using a two-sample Mendelian randomization approach.

The goal was to explore the effect of interleukin-6 (IL6) and C reactive protein (CRP) on malignant melanoma (MM) using two-sample Mendelian randomization. Methods: Data for this study were obtained from the IEU Open GWAS project website for genome-wide association study data (GWAS) on interleukin-6, C reactive protein levels and malignant melanoma. Inverse variance weighted (IVW) method was mainly used and supplemented with MR-Egger regression and weighted median. Finally, horizontal multivariate validity and heterogeneity tests were performed to assess the stability and reliability of the results. Results: The results of univariate two-sample MR analyses showed no significant effect of CRP on MM: inverse variance weighting method (OR=0.999, 95% CI: 0.998-1.001, P=0.343), MR-Egger regression (OR= 1.000, 95% CI: 0.998-1.001, P= 0.180), and weighted median method (OR= 0.999, 95% CI: 0.997 to 1.000, P= 0.583), and weighted model (OR= 0.999, 95% CI: 0.998 to 1.001, P= 0.328). Also,IL-6 had no significant effect on MM: inverse variance weighting method (OR= 1.001, 95% CI: 0.999 to 1.002, P=0.461), MR-Egger regression (OR= 1.000, 95% CI: 0.997 to 1.004, P= 0.910), weighted median method (OR= 1.000, 95% CI: 0.998 to 1.002, P= 0.749), and weighted mode (OR= 1.000, 95% CI: 0.998 to 1.002, P= 0.820). Conclusion: There was no causal relationship between C-reactive protein and IL-6 on the risk of malignant melanoma.

Preclinical safety of a bionic tiger bone capsule in Sprague-Dawley rats and beagle dogs.

BACKGROUND: Jintiange capsule is composed of bionic tiger bone powder and has similar ingredients to natural tiger bone. OBJECTIVE: To characterize the subacute toxicities of Jintiange capsule in rats and beagle dogs for preclinical safety assessment. METHODS: Suspensions of Jintiange capsule were given via gastric lavage over a 26-week period at low (500 mg/kg), mid (1500 mg/kg) and high doses (4000 mg/kg) in SD rats. Beagles were given by gastric lavage of suspensions of Jintiange capsule once daily for 6 days per week for 39 weeks at low (300 mg/kg), mid (900 mg/kg) or high dose (2000 mg/kg). RESULTS: Repeated gastric lavages of suspensions of Jintiange capsule at doses from 500 to 4000 mg/kg over 26 weeks caused no significant toxicity (No Observed Adverse Effect Level, NOAEL) in rats. In addition, repeated gastric lavages of suspensions of Jintiange capsule at doses from 300 to 2000 mg/kg over 39 weeks caused NOAEL in beagles. CONCLUSIONS: Jintiange capsule was safe in rats at a dose 66.7 times the clinically recommended dose and in beagles at 33.3 times the clinically recommended dose. Our subacute toxicity studies in rats and beagles demonstrated no apparent overall toxicities including haematotoxicities, hepatotoxicities and renal toxicities.

Corydaline and l-tetrahydropalmatine attenuate morphine-induced conditioned place preference and the changes in dopamine D2 and GluA1 AMPA receptor expression in rats.

Corydalis is a Chinese herb that has been used in China for hundreds of years for analgesic and other purposes. Corydaline and l-tetrahydropalmatine (l-THP) are the main active ingredients of Corydalis. This study was aimed to study the potential utility of corydaline and l-THP in the treatment of opioid abuse and addiction and explore the possible mechanisms underlying their pharmacological actions. Conditioned place preference (CPP) was used to evaluate the rewarding effects of morphine and Western-blot immunoreactive assays were used to evaluate morphine-induced changes in dopamine D2 receptor and GluA1 AMPA receptor and GluA2 AMPA receptor expression in the brain of rats. Systemic administration of corydaline (5 mg/kg, i.p.) or l-THP (1.25, 2.5,5 mg/kg) significantly inhibited the acquisition and expression of morphine-induced CPP in a dose-dependent manner. Corydaline or l-THP alone, at the same doses, failed to produce CPP or conditioned place aversion, and didn't affect locomotor activity. We then examined the expression of dopamine D2 receptor and GluA1 AMPA receptor and GluA2 AMPA receptor subunit expression in rats after acquisition of morphine-induced CPP. We found that repeated administration of morphine produced a significant reduction in dopamine D2 receptor expression in the prefrontal cortex, hippocamps, and striatum, while an increase in the striatal GluA1 AMPA receptor expression. Pretreatment with corydaline or l-THP blocked morphine-induced dopamine D2 receptor down-regulation and GluA1 AMPA receptor up-regulation in these brain regions. Corydaline and l-THP may have therapeutic potential in prevention and treatment of opioid abuse and addiction. The underlying mechanisms may be related to their antagonism on morphine-induced changes in dopamine and glutamate transmission in the brain.

Characterizing the mechanism of thiazolidinedione-induced hepatotoxicity: An in vitro model in mitochondria.

OBJECTIVE: To characterize the mechanism of action of thiazolidinedione (TZD)-induced liver mitochondrial toxicity caused by troglitazone, rosiglitazone, and pioglitazone in HepaRG cells. METHODS: Human hepatoma cells (HepaRG) were treated with troglitazone, rosiglitazone, or pioglitazone (12.5, 25, and 50µM) for 48h. The Seahorse Biosciences XF24 Flux Analyzer was used to measure mitochondrial oxygen consumption. The effect of TZDs on reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected by flow cytometry. The mitochondrial ultrastructure of HepaRG cells was observed under a transmission electrical microscope (TEM). mtDNA content was evaluated by real-time PCR, and ATP content and mitochondrial respiratory chain (MRC) complex I, II, III, IV activity were measured via chemiluminescence. Results were considered statistically significant at p<0.05. RESULTS: Among the three drugs, troglitazone exhibited the highest potency, followed by rosiglitazone, and then pioglitazone. The TZDs caused varying degrees of mitochondrial respiratory function disorders including decreases in oxygen consumption, MRC activity, and ATP level, and an elevation in ROS level. TZD treatment resulted in mtDNA content decline, reduction in MMP, and alterations of mitochondrial structure. CONCLUSION: All investigated TZDs show a certain degree of mitochondrial toxicity, with troglitazone exhibiting the highest potency. The underlying mechanism of TZD-induced hepatotoxicity may be associated with alterations in mitochondrial respiratory function disorders, oxidative stress, and changes in membrane permeability. These parameters may be used early in drug development to further optimize risk:benefit profiles.

Subchronic toxicological study of two artemisinin derivatives in dogs.

The objective of our study was to profile and compare the systematic changes between orally administered artesunate and intramuscularly injected artemether at a low dose over a 3-month period (92 consecutive days) in dogs. Intramuscular administration of 6 mg kg-1 artemether induced a decreased red blood cell (RBC) count (anemia), concurrent extramedullary hematopoiesis in the spleen and inhibition of erythropoiesis in the bone marrow. We also observed a prolonged QT interval and neuropathic changes in the central nervous system, which demonstrated the cortex and motor neuron vulnerability, but no behavioral changes. Following treatment with artesunate, we observed a decreased heart rate, which was most likely due to cardiac conduction system damage, as well as a deceased RBC count, extramedullary hematopoiesis in the spleen and inhibition of erythropoiesis in the bone marrow. However, in contrast to treatment with artemether, neurotoxicity was not observed following treatment with artesunate. In addition, ultra-structural examination by transmission electron microscopy showed mitochondrial damage following treatment with artesunate. These findings demonstrated the spectrum of toxic changes that result upon treatment with artesunate and artemether and show that the prolonged administration of low doses of these derivatives result in diverse toxicity profiles.