Identification of small molecules that improve ATP synthesis defects conferred by Leber's hereditary optic neuropathy mutations.

Inherited mitochondrial complex I mutations cause blinding Leber's hereditary optic neuropathy (LHON), for which no curative therapy exists. A specific biochemical consequence of LHON mutations in the presence of trace rotenone was observed: deficient complex I-dependent ATP synthesis (CIDAS) and mitochondrial O2 consumption, proportional to the clinical severity of the three primary LHON mutations. We optimized a high-throughput assay of CIDAS to screen 1600 drugs to 2, papaverine and zolpidem, which protected CIDAS in LHON cells concentration-dependently. TSPO and cAMP were investigated as protective mechanisms, but a conclusive mechanism remains to be elucidated; next steps include testing in animal models.

The significance of putative urinary markers of illicit heroin use after consumption of poppy seed products.

After consumption of poppy seeds various substances were detected in urine or blood samples using an immunoassay and a sophisticated liquid chromatographic-tandem mass spectrometric procedure. These compounds are widely considered to be putative markers of heroin (HER) abuse whereas acetylcodeine was regarded as a marker for illicit preparations ("street HER"). Besides positive urinary opiate immunoassay results during a 48 hours monitoring period, peak concentrations of morphine (MOR), codeine and their glucuronides appeared 4 to 8 hours after ingestion of poppy seeds, and concentrations of total MOR higher than 10 microg/mL were observed. Also, in serum samples taken up to 6 hours after consumption, MOR glucuronides were found. Free MOR was only detected in traces (1 to 3 ng/mL) within 2 hours of consumption. In addition, 3 of 6 onsite opiate sweat tests revealed positive results 6.5 hours after ingestion. Furthermore, it was demonstrated that neither noscapine (NOS) nor papaverine (PAP) was detectable in urine or blood samples after the consumption of poppy seeds containing up to 94 microg NOS and up to 3.3 mug PAP. NOS and PAP were rapidly metabolized, whereas desmethylpapaverine and, especially, its glucuronide were found in urine samples of poppy seed consumers even 48 hours after consumption. According to these results PAP metabolites should not be regarded as markers of illicit HER abuse. In conclusion, only acetylcodeine can be regarded as a specific marker but has the problem of a short half-life. Therefore, we suggest that NOS and PAP, but not their metabolites, might be used cautiously as additional markers of illicit HER abuse as they have not been detected after oral intake of poppy seeds in normal doses. But it must be kept in mind that in some cases poppy seeds with an unusually high content of these alkaloids could be available, and that these substances are also agents in some pharmaceuticals.

[Sustained-release pellet of vasodilators--basic experiment].

We examined the efficacy of slow-release, and prolonged diffusion silicone pellets mixed with papaverine hydrochloride in the treatment of cerebral vasospasms following subarachnoid hemorrhage. In addition the diffusion of the other vasodilating agents (diltiazem and nicardipine) into the saline solution using the same silicone materials was also investigated. Papaverine hydrochloride was either packed in silicone tubes (packed type) or polymerized with silicone elastomer, Silastic MDX-4-4210 (solid type). The solid type pellet is cylindrical-(diameter 3 mm, length 30 mm) and contains 40 w/v% of pure powder of papaverine. The amount of the delivered drug was measured for 5 weeks at 37 degrees C and at room temperature. The diffusion rate of the solid type pellet was about 5 times higher than that of the packed one. The diffusion rates of both types of pellets were about 10 times higher at 37 degrees C than at room temperature. The cummulative amount of the delivered drug from the solid type pellet was 37.1% of the initial packed volume at 37 degrees C in the first 3 weeks. The diffusion of diltiazem and nicardipine which were polymerized 30 w/v% in silicone elastomer was observed for 3 weeks at 37 degrees C only in solid type pellet form. The diffusion rate was measured under the condition of either continuous shaking or standing. The results showed the same diffusion rates for diltiazem and nicardipine, with no difference in diffusion rate between the "shaking" and "standing" groups. The diffusion rate showed inverse exponential curves, and was 5-20 X 10(-5)/day/mm2 of initial volume until 5 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Microbial models of mammalian metabolism.

A solid basis for the M4-approach has been developed over the past 10 years. Recent examples of the production of difficult-to-synthesize mammalian metabolites through microbial transformations attest to the utility of the methodology. There is, however, much more to be done. Model studies should be conducted to test parallels between microbial and mammalian S- and N-oxidations, O-glucuronidations, and ester and amide hydrolyses. Subsequently, even greater applications of M4- work can be envisioned. We have been pleased to see our colleagues in industry and academia adopt the M4- approach to solve difficult pharmacological and toxicological problems. In large measure, this has been our greatest reward for efforts initially presented before the membership of the American Society of Pharmacognosy in 1973.