Protein hydrolysates from <i>Hermetia illucens</i> trigger cellular responses to cope with LPS-induced inflammation and oxidative stress in L-929 cells

Insect protein hydrolysates (PH) are emerging as valuable compounds with biological activity. The aim of the present study was to assess the potential cytoprotective effects of PH from the Black Soldier Fly (BPH, in the range 0.1-0.5 mg/mL) against inflammatory conditions and oxidative stress in LPS-challenged L-929 cells. BPH was effective in inhibiting LPS-induced ROS and nitrite production and in reducing the protein and transcript levels of remarkable inflammatory markers, such as TNF-α, IL-6, IL-1α, and IL-1β, as determined by ELISA and/or qPCR. Moreover, the BPH antioxidant and anti-inflammatory activities rely on the induction of selected genes and proteins involved in the antioxidant response (i.e. <i>Cu/ZnSod, MnSod</i>, <i>Gpx</i>, <i>HO-1</i>) through <i>Nrf2</i>, as well as on the inhibition of the activation of NF-κB, a key player in inflammation. These findings suggest that BPH represents effective bioactive compounds with therapeutic potential for mitigating oxidative stress and inflammation in vitro, thus deserving further investigation into the underlying mechanisms before BPH application as novel drugs in the near future.