Latest research on Quinine

An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood. [PubChem]

Latest findings

The first available anti-malarial drug in Angola, as in all the Western World, was Quinine mono-therapy, introduced during the Portuguese colonial times. [source, 2016]
Albeit clinical failure with Quinine therapies had been known for decades, there are no reliable reports of drug resistance when used in the country during the first decades of the 20th Century. [source, 2016]
Study participants diagnosed with malaria received artemether/lumefantrine and, in severe cases, Quinine. [source, 2016]
In pharmacological experiments, 100 μM BaCl2 and 400 μM Quinine were dissolved directly in aCSF for bath application to block astrocytic Kir4.1 and K2Ps, respectively. [source, 2016]
Quinine is a potent TWIK-1 and TREK-1 inhibitor (Zhou et al., 2009). [source, 2016]
To examine and compare K2P conductance selectively in gene knockout astrocytes, the Kir4.1 was first inhibited by 100 μM BaCl2, and that was followed by addition of 400 μM Quinine. [source, 2016]
Under these conditions, Quinine further depolarized astrocyte VM (ΔVM1) by 7.4 ± 0.50 mV (n = 14) in WT, 7.4 ± 1.30 mV (n = 7) in TREK-1−/−, 7.2 ± 0.44 mV (n = 16) in TWIK-1−/− and 7.4 ± 0.68 mV (n = 11) in TWIK-1−/−/TREK-1−/− astrocytes (P > 0.05, Figures 7A,B). [source, 2016]
Total VM depolarization (ΔVM2) induced by 100 μM BaCl2 and 400 μM Quinine was also comparable in the four genotypes: 10.6 ± 0.62 mV (n = 14) in WT, 10.6 ± 1. [source, 2016]
In voltage clamp recording, 400 μM Quinine produced similar inhibition of passive conductance as compared with WT, TREK-1−/−, TWIK-1−/− and TWIK-1−/−/TREK-1−/− astrocytes (Figure 7C). [source, 2016]
Specifically, in the presence of 400 μM Quinine and 100 μM BaCl2, the RI of Quinine and Ba2+-insensitive currents was comparable between WT, TREK-1−/−, TWIK-1−/− and TWIK-1−/−/TREK-1−/− astrocytes: 1.04 ± 0.01 (n = 5) in WT, 1.04 ± 0.06 (n = 5) in TREK-1−/−, 1.03 ± 0.02 (n = 6) in TWIK-1−/− and 1.04 ± 0.01 (n = 8) in TWIK-1−/−/TREK-1−/− astrocytes (P > 0.05, Figure 7D). [source, 2016]