Allele-selective lowering of mutant HTT protein by HTT-LC3 linker compounds.

Accumulation of mutant proteins is a major cause of many diseases (collectively called proteopathies), and lowering the level of these proteins can be useful for treatment of these diseases. We hypothesized that compounds that interact with both the autophagosome protein microtubule-associated protein 1A/1B light chain 3 (LC3)1 and the disease-causing protein may target the latter for autophagic clearance. Mutant huntingtin protein (mHTT) contains an expanded polyglutamine (polyQ) tract and causes Huntington's disease, an incurable neurodegenerative disorder2. Here, using small-molecule-microarray-based screening, we identified four compounds that interact with both LC3 and mHTT, but not with the wild-type HTT protein. Some of these compounds targeted mHTT to autophagosomes, reduced mHTT levels in an allele-selective manner, and rescued disease-relevant phenotypes in cells and in vivo in fly and mouse models of Huntington's disease. We further show that these compounds interact with the expanded polyQ stretch and could lower the level of mutant ataxin-3 (ATXN3), another disease-causing protein with an expanded polyQ tract3. This study presents candidate compounds for lowering mHTT and potentially other disease-causing proteins with polyQ expansions, demonstrating the concept of lowering levels of disease-causing proteins using autophagosome-tethering compounds.

Effects of Hedan Tablet () on lipid profile, proprotein convertase subtilisin/kexin type 9 and high-density lipoprotein subfractions in patients with hyperlipidemia: A primary study.

OBJECTIVE: To investigate the effects of Hedan Tablet () on serum lipid profile, proprotein convertase subtilisin/kexin type 9 (PSCK9) and high-density lipoprotein (HDL) subfractions in patients with hyperlipidemia. METHODS: Thirty-seven patients with hyperlipidemia were randomized to treatment with Hedan Tablet 4.38 g/day as Hedan group (18 cases) or placebo (19 cases) as control group for 8 weeks. The lipid profile, PCSK9 and HDL subfractions were determined at day 0 and week 8 in both groups respectively. RESULTS: Hedan treatment for 8 weeks mildly decreased serum low-density lipoprotein cholesterol (LDL-C) levels, while no changes were found in total cholesterol (TC), triglycerides (TG) and PCSK9 concentrations. Furthermore, Hedan treatment increased the concentration of large high-density lipoprotein cholesterol (HDL-C) and the percentage of large HDL subfraction, while decreased the concentration of small HDL-C and the percentage of small HDL subfraction without changing serum HDL-C levels in patients with hyperlipidemia. CONCLUSION: Hedan treatment of 4.38 g per day for 8 weeks could confer a favorable effects on serum LDL-C concentration as well as HDL subfractions.

Policosanol attenuates statin-induced increases in serum proprotein convertase subtilisin/kexin type 9 when combined with atorvastatin.

Objective. Statin treatment alone has been demonstrated to significantly increase plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) levels. The effect of policosanol combined with statin on PCSK9 is unknown. Methods. Protocol I: 26 patients with atherosclerosis were randomly assigned to receive either atorvastatin 20 mg/d or policosanol 20 mg/d + atorvastatin 20 mg/d for 8 weeks. Protocol II: 15 healthy volunteers were randomly assigned to either policosanol 20 mg/d or a control group for 12 weeks. Serum levels of PCSK9 were determined at day 0 and the end of each protocol. Results. Protocol I: atorvastatin 20 mg/d significantly increased serum PCSK9 level by 39.4% (256 ± 84 ng/mL versus 357 ± 101 ng/mL, P = 0.002). However, policosanol 20 mg/d + atorvastatin 20 mg/d increased serum PCSK9 level by only 17.4% without statistical significance (264 ± 60 ng/mL versus 310 ± 86 ng/mL, P = 0.184). Protocol II: there was a trend toward decreasing serum PCSK9 levels in the policosanol group (289 ± 71 ng/mL versus 235 ± 46 ng/mL, P = 0.069). Conclusion. Policosanol combined with statin attenuated the statin-induced increase in serum PCSK9 levels. This finding indicates that policosanol might have a modest effect of lowering serum PCSK9 levels.

Celastrol attenuates inflammatory and neuropathic pain mediated by cannabinoid receptor type 2.

Celastrol, a major active ingredient of Chinese herb Tripterygium wilfordii Hook. f. (thunder god vine), has exhibited a broad spectrum of pharmacological activities, including anti-inflammation, anti-cancer and immunosuppression. In the present study, we used animal models of inflammatory pain and neuropathic pain, generated by carrageenan injection and spared nerve injury (SNI), respectively, to evaluate the effect of celastrol and to address the mechanisms underlying pain processing. Intraperitoneal (i.p.) injection of celastrol produced a dose-dependent inhibition of carrageenan-induced edema and allodynia. Real-time PCR analysis showed that celastrol (0.3 mg/kg, i.p.) significantly reduced mRNA expressions of inflammatory cytokines, TNF-α, IL-6, IL-1ß, in carrageenan-injected mice. In SNI mice, pain behavior studies showed that celastrol (1 mg/kg, i.p.) effectively prevented the hypersensitivity of mechanical nociceptive response on the third day post-surgery and the seventh day post-surgery. Furthermore, the anti-hyperalgesic effects of celastrol in carrageenan-injected mice and SNI mice were reversed by SR144528 (1 mg/kg, i.p.), a specific cannabinoid receptor-2 (CB2) receptor antagonist, but not by SR141716 (1 mg/kg, i.p.), a specific cannabinoid receptor-1 (CB1) receptor antagonist. Taken together, our results demonstrate the analgesia effects of celastrol through CB2 signaling and propose the potential of exploiting celastrol as a novel candidate for pain relief.

Short-term impact of low-dose atorvastatin on serum proprotein convertase subtilisin/kexin type 9.

BACKGROUND AND OBJECTIVE: Several small studies have found that moderate- to high-dose statins (HMG-CoA reductase inhibitors) could increase the serum proprotein convertase subtilisin/kexin type 9 (PCSK9) level. However, little is known regarding the short-term, dose-dependent effects of low-dose atorvastatin and the rapid effects of a single dose of atorvastatin on PCSK9. The objective of this study was to investigate the short-term impact of low-dose atorvastatin on PCSK9 in humans. METHODS: In this randomized study, data from 66 subjects were analyzed. In protocol I, 32 patients were randomized to atorvastatin 10 mg/day (n = 19) or 20 mg/day (n = 13) and eight healthy subjects without therapy were controls for 8 weeks. Serum PCSK9 and lipid profile were determined at day 0, week 4, and week 8. In protocol II, 26 patients were randomized to a single dose of atorvastatin 10 mg (n = 11) or 80 mg (n = 15), and serum levels of PCSK9 were measured at 24 h after treatment. RESULTS: Atorvastatin 10 mg/day decreased low-density lipoprotein cholesterol (LDL-C) by 32 % at 4 weeks and by 33 % at 8 weeks, and atorvastatin 20 mg/day resulted in reduction of LDL-C by 41 % at 4 weeks and by 38 % at 8 weeks. Atorvastatin 10 mg/day slightly increased serum PCSK9 by 5-7 % but without a significant difference, while atorvastatin 20 mg/day significantly increased serum PCSK9 by 30 % at 4 weeks and by 35 % at 8 weeks (p = 0.009 and p = 0.002, respectively). In addition, 24 h after a single dose, atorvastatin 10 mg significantly increased serum PCSK9 by 13 % and atorvastatin 80 mg by 27 % (p = 0.042 and p = 0.001, respectively). CONCLUSION: The short-term impact of low-dose atorvastatin on PCSK9 was time and dose dependent, with a rapid increase in PCSK9 levels being observed within 24 h of dosing.