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Biology subjects

Uta, D.

Publications and source records attributed to Uta, D..

3 recordsLinked to original sources

Novel humanized anti-Nav1.7 antibodies with long-lasting, side-effect-free analgesic effects

Neuropathic pain remains difficult to treat effectively because of the limitations of current pain medications. The Nav1.7 sodium channel plays a crucial role in pain sensation. The development of selective inhibitors has been challenging because of the high similarity among Nav channel subtypes. To address this issue, we developed monoclonal antibodies that selectively target Nav1.7 and humanized them for clinical use for the first time. When administered systemically to neuropathic pain model rats, a potent analgesic effect was observed that lasted for at least 96 hours. Electrophysiological studies revealed that the antibody reduced mechanically-evoked and spontaneous neuronal activity in the model. Importantly, the antibodies did not impact physiological pain or motor function. Collectively, our findings suggest that these novel Nav1.7-targeting antibodies are potentially effective analgesic drugs for chronic pain, including neuropathic pain. Our novel humanized anti-Nav1.7 antibodies have the potential to be used for the development of new analgesic, and one such antibody, S-151128 is currently in clinical trial.

pharmacology and toxicology↗

Androgen receptors expressed in the primary sensory neurons regulate mechanical pain sensitivity

The expression of hormonal receptors in pain-processing regions complicates understanding the hormonal effects on pain mechanisms. This study investigates androgen receptor (AR) involvement in pain sensitivity and sex differences in pain perception. Mechanical pain thresholds were higher in normal male mice compared to gonadectomized (GDX) male and normal female mice, correlating with serum testosterone levels. In the dorsal root ganglia (DRG), AR was expressed in normal males but undetectable in GDX males and normal females. In male sensory neuron-selective AR conditional knockout (AR-cKO) mice, mechanical pain thresholds were significantly lower than in wild-type males. In female mice, administration of testosterone propionate or dihydrotestosterone significantly raised mechanical pain thresholds, accompanied by increased AR expression in the DRG. This effect was abolished in AR-cKO females, consistent with male findings. These results indicate that primary sensory neurons are critical targets of androgen signaling in regulating mechanical pain sensitivity.

neuroscience↗

Inhibition of TRPV1 and TRPA1 by mosquito and mouse saliva

Arthropods are the largest group of living organisms and among them, mosquitoes spread parasites and viruses causing deathly diseases. Mosquitos painless piercing is due to the thinness of their fascicle, but mosquito saliva might also contribute to it. We found that mosquito and mouse saliva inhibit TRPV1 and TRPA1 channels, either heterologously expressed in HEK293T cells or endogenously expressed in native mouse sensory neurons. We have also identified sialorphin as a candidate antinociceptive peptide as it showed similar effects on TRPV1 and TRPA1. Finally, we confirmed the antinociceptive effects of saliva and sialorphin in vivo by observing decreased pain-related behaviors in mice coinjected with these substances. Similar inhibitory effects of mosquito and mouse saliva suggest that the antinociceptive effects of saliva are universal, which could explain why many animals including humans often lick their wounds. These findings would lead to the development of novel anti-nociceptive agents.

cell biology↗