[Treatment of type 2 diabetic peripheral neuropathy patients of qi-yin deficiency complicated phlegm-dampness blocking collaterals syndrome by internal application of qigui mixture and external application of qigui huoxue lotion: a clinical study].

OBJECTIVE: To evaluate the efficacy of internal application of Qigui Mixture (QM) and external application of Qigui Huoxue Lotion (QHL) in treating type 2 diabetic peripheral neuropathy (DNP) patients of qi-yin deficiency complicated phlegm-dampness blocking collaterals syndrome (QYD-PDBCS), and to primarily discuss its mechanism. METHODS: Totally 62 DPN patients of QYD-PDBCS were randomly assigned to the treatment group (31 cases) and the control group (31 cases). All patients received routine comprehensive therapy. Patients in the control group took Mecobalamine Tablet, 500 microg each time, 3 times per day. Patients in the treatment group additionally took QM, 200 mL per day, twice daily. Besides, they had foot bath in QHL 10 - 15 min every evening for 3 months. The efficacy was assessed by Chinese medical symptom integrals and Toronto clinical scoring system (TCSS) before treatment, 2 and 3 months after treatment. The nerve conduction velocity was determined; the serum levels of total antioxidant capacity (T- AOC), malondialdehyde (MDA), and superoxide dismutase (SOD) were detected 2 and 3 months after treatment. RESULTS: The total effective rates of Chinese medical symptom integrals and TCSS score were obviously higher in the treatment group than in the control group (P < 0.05). The nerve conduction velocity was significantly improved in the treatment group, when compared with before treatment (P < 0.01). There was statistical difference in the nerve conduction velocity difference of right median nerve motor branch, bilateral tibial nerve motor branches, bilateral common peroneal nerve motor branches, bilateral ulnar nerve sensory branches, and left tibial nerve sensory branch (P < 0.05). Compared with before treatment, serum levels of T-AOC and SOD significantly increased, and the level of MDA decreased significantly in the treatment group after 2 and 3 months of treatment (P < 0.01). But only the SOD level increased significantly in the control group (P < 0.01). There was no statistical difference in increased T-AOC level between the two groups after 2 months of treatment (P > 0.05), but there was statistical difference in increased SOD level and decreased MDA level (P < 0.05). There was statistical difference in increased T-AOC and SOD levels and decreased MDA level between the two groups after 3 months of treatment (P < 0.05). No adverse reaction occurred during the therapeutic course. CONCLUSIONS: The internal application of QM and external application of QHL combined with Mecobalamine in treating DPN was safe and effective, with more significant efficacy than using Mecobalamine alone. Its mechanism might be associated with resistance to oxidative stress.

Inhibition of aldehyde dehydrogenase-2 suppresses cocaine seeking by generating THP, a cocaine use-dependent inhibitor of dopamine synthesis.

There is no effective treatment for cocaine addiction despite extensive knowledge of the neurobiology of drug addiction. Here we show that a selective aldehyde dehydrogenase-2 (ALDH-2) inhibitor, ALDH2i, suppresses cocaine self-administration in rats and prevents cocaine- or cue-induced reinstatement in a rat model of cocaine relapse-like behavior. We also identify a molecular mechanism by which ALDH-2 inhibition reduces cocaine-seeking behavior: increases in tetrahydropapaveroline (THP) formation due to inhibition of ALDH-2 decrease cocaine-stimulated dopamine production and release in vitro and in vivo. Cocaine increases extracellular dopamine concentration, which activates dopamine D2 autoreceptors to stimulate cAMP-dependent protein kinase A (PKA) and protein kinase C (PKC) in primary ventral tegmental area (VTA) neurons. PKA and PKC phosphorylate and activate tyrosine hydroxylase, further increasing dopamine synthesis in a positive-feedback loop. Monoamine oxidase converts dopamine to 3,4-dihydroxyphenylacetaldehyde (DOPAL), a substrate for ALDH-2. Inhibition of ALDH-2 enables DOPAL to condense with dopamine to form THP in VTA neurons. THP selectively inhibits phosphorylated (activated) tyrosine hydroxylase to reduce dopamine production via negative-feedback signaling. Reducing cocaine- and craving-associated increases in dopamine release seems to account for the effectiveness of ALDH2i in suppressing cocaine-seeking behavior. Selective inhibition of ALDH-2 may have therapeutic potential for treating human cocaine addiction and preventing relapse.