Inclusion criteria
We applied the PICOS strategy to establish the inclusion criteria. Population (P): RAW 264.7 macrophages derived from murine/Mus musculus, cell culture medium Dulbecco’s Modified Eagle Medium (DMEM). The use of this cell culture medium in the studies was chosen as an eligibility criterion, according to the ATCC base medium recommendation for this cell line (American Type Culture Collection - ATCC, 2018). Intervention (I)/Exposure: Any form of intervention with LPS at a concentration of 1 µg/mL (inflammatory inductor of RAW 264.7 macrophages), and exposure time of between 12 to 48 hours. Comparator(s)/control (C): RAW 264.7 macrophages not induced by LPS (basal control group). Outcome (O)/ measure(s): Levels or concentration of NO or metabolites (µM), and at least one of the following cytokines:  TNFα, IL-1β, and IL-6 (pg mL-1). Only studies that showed NO production over 20 µM by LPS-induced RAW 264.7 macrophages were included. These conditions were established based on previous studies published by our laboratory using this experimental model (Biluca et al., 2020; Duarte et al., 2018; Mohr et al., 2019). Other important references in the field have also used the same experimental protocol (Chen et al., 2016; Jung et al., 2013; Yoon et al., 2009). Study designs (S) included: Only original articles from in vitro studies (RAW 264.7 macrophages), with separate control cells. Articles written in English, published in the last five years (From January 1, 2015 to May 31, 2020).