Search of inhibitors of aldose reductase for treatment of diabetic cataracts using machine learning

Purpose:Patients with diabetes mellitus have an elevated chance of developing cataracts,a degenerative visionimpairing condition often needing surgery.The process of the reduction of glucose to sorbitol in the lens of the human eye that causes cataracts is managed by the Aldose Reductase Enzyme(AR),and it is been found that AR inhibitors may mitigate the onset of diabetic cataracts.There exists a large pool of natural and synthetic AR inhibitors that can prevent diabetic complications,and the development of a machine-learning(ML)prediction model may bring new AR inhibitors with better characteristics into clinical use.Methods:Using known AR inhibitors and their chemical-physical descriptors we created the ML model for prediction of new AR inhibitors.The predicted inhibitors were tested by computational docking to the binding site of AR.Results:Using cross-validation in order to find the most accurate ML model,we ended with final cross-validation accuracy of 90%.Computational docking testing of the predicted inhibitors gave a high level of correlation between the ML prediction score and binding free energy.Conclusions:Currently known AR inhibitors are not used yet for patients for several reasons.We think that new predicted AR inhibitors have the potential to possess more favorable characteristics to be successfully implemented after clinical testing.Exploring new inhibitors can improve patient well-being and lower surgical complications all while decreasing long-term medical expenses.

Epalrestat protects against diabetic peripheral neuropathy by alleviating oxidative stress and inhibiting polyol pathway

Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.

Efficacy of epalrestat plus α-lipoic acid combination therapy versus monotherapy in patients with diabetic peripheral neuropathy: a meta-analysis of 20 randomized controlled trials

OBJECTIVE： To evaluate the efficacy of α-lipoic acid（ALA） plus epalrestat combination therapy in the treatment of diabetic peripheral neuropathy（DPN）. DATA SOURCES： The electronic databases of Pub Med, Medline, Embase, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Wanfang Database and the Chinese Biomedical Database were used to retrieve relevant studies without language restrictions. The search was conducted from the inception of each database to 7 October 2016. The key terms were（diabetic peripheral neuropathy or diabetic neuropathy or DPN） AND（α-lipoic acid or lipoic acid or thioctic acid） AND epalrestat. DATA SELECTION： All of the eligible studies met the following inclusion criteria：（1） Randomized controlled trials that compared efficacy and safety of epalrestat plus ALA combination therapy versus epalrestat or ALA monotherapy in patients with DPN.（2） The minimum duration of treatment was 2 weeks.（3） The DPN patients were diagnosed using the World Health Organization standardized type 2 diabetes mellitus and DPN criteria.（4） Studies contained at least one measure that could reflect the efficacy of the drug and nerve conduction velocities. Studies in which the control group used epalrestat or ALA combined with other drugs were excluded. Statistical analyses were performed using STATA software for meta-analysis. OUTCOME MEASURES： The primary outcomes were the therapeutic efficacy, median motor nerve conduction velocity（MNCV）, median sensory nerve conduction velocity（SNCV）, peroneal MNCV and peroneal SNCV.RESULTS： Twenty studies with 1894 DPN patients were included, including 864 patients in the ALA plus epalrestat group, 473 in the ALA group and 557 in the epalrestat group. The efficacy of ALA plus epalrestat combination therapy was superior to ALA and epalrestat monotherapies（RR = 1.29, 95% CI： 1.21–1.38; RR = 1.43, 95% CI： 1.34–1.54, respectively）. ALA plus epalrestat combination therapy also significantly improved median MNCV（WMD = 5.41, 95% CI： 2.07–8.75）, median SNCV（WMD = 5.87, 95% CI： 1.52–10.22）, peroneal MNCV（WMD = 5.59, 95% CI： 2.70–8.47） and peroneal SNCV（WMD = 4.57, 95% CI： 2.46–6.68）.CONCLUSION： ALA plus epalrestat combination therapy was superior to ALA and epalrestat monotherapies for clinical efficacy and nerve conduction velocities in patients with DPN.

ORIGINAL ARTl CLESSilybin Decreases Erythrocytic Sorbitol Level and ImprovesPeripheral Nerve Conduction Velocity in Patients with Non-lnsulin Dependent Diabetes Mellitus

The effects of silybin on erythrocytic sorbitol level and peripheral nerve conduction veloci-ty were studied in 14 cases of noninsulin dependent diabetes mellitus (NIDDM) . Atter oral administrationof silybin 231 mglday for 4 weeks, no blood glucose change was observed in patients with NIDDM, whilethe erythrocytic sorbitol level was significantly decreased from 72. 55 21. 61 to 39. 53 14. 94 nmol/g .Hb (P<0. 01) . At the same time, peripheral nerve conduction vefocity was also improved. These resultsindicate that silybin is an effective aldose reductase inhibitor which can improve the disorder of polyolpathway in NIDDM patients and prevent chronic complications of diabetes.