3.1 Characteristics of the included studies
The 19 included literatures are all in English, and a total of 370
animals were included, including 180 animals in the experimental group
and 190 animals in the control group (Figure 3) . Animal species
include Sprague-Dawley rats(SD rats)(Y. Deng et al., 2016; J. Guo et
al., 2010; Xiong et al., 2016; F. Zhang et al., 2015; L. Zhang et al.,
2017), C57BL mice(H. Li et al., 2018; Shao et al., 2015; Tao et al.,
2013; Wu et al., 2011; Xie et al., 2018; C. Q. Xu et al., 2010), BALB/c
mice(L. Li et al., 2014; P. Ma et al., 2015; Wei et al., 2015; J. Zhou
et al., 2011), Wistar rats(Fu et al., 2018; Y. Hu et al., 2016), MRL/lpr
mice(Su et al., 2018) and Minipigs(X. Zhang et al., 2018). Inflammatory
diseases studied include local inflammation(L. Li et al., 2014; Wu et
al., 2011; X. Zhang et al., 2018), circulatory system inflammation(Fu et
al., 2018; Y. Hu et al., 2016), urinary system inflammation(P. Ma et
al., 2015; Su et al., 2018; Xie et al., 2018; L. Zhang et al., 2017),
nervous system inflammation(Y. Deng et al., 2016; J. Guo et al., 2010;
H. Li et al., 2018; Xiong et al., 2016), respiratory system
inflammation(Wei et al., 2015; C. Q. Xu et al., 2010), Digestive system
inflammation(Tao et al., 2013; F. Zhang et al., 2015), Motion system
inflammation(Shao et al., 2015) and tumor-associated inflammation(J.
Zhou et al., 2011) (Table 1).
According to the inclusion and exclusion criteria, all animal models
were models of inflammation-related diseases. The experimental group
received monotherapy with icariin or its derivatives, and the control
group received only normal saline or distilled water. In order to
evaluate the effect of icariin and its derivatives on the treatment of
inflammatory diseases, 12 literatures reported the level of TNF-α(Fu et
al., 2018; J. Guo et al., 2010; Y. Hu et al., 2016; H. Li et al., 2018;
L. Li et al., 2014; Shao et al., 2015; Su et al., 2018; Tao et al.,
2013; Wu et al., 2011; Xie et al., 2018; C. Q. Xu et al., 2010; F. Zhang
et al., 2015), 10 literatures reported the level of IL-1β(Y. Deng et
al., 2016; Fu et al., 2018; J. Guo et al., 2010; H. Li et al., 2018;
Shao et al., 2015; Su et al., 2018; Xie et al., 2018; Xiong et al.,
2016; L. Zhang et al., 2017; X. Zhang et al., 2018), and 6 literatures
reported the level of IL-6(Fu et al., 2018; Y. Hu et al., 2016; Shao et
al., 2015; Wei et al., 2015; Xie et al., 2018; F. Zhang et al., 2015), 5
literatures reported the level of TGF-β1(Y. Deng et al., 2016; Fu et
al., 2018; Wei et al., 2015; Xiong et al., 2016; L. Zhang et al., 2017),
5 literatures reported the level of SOD(Y. Hu et al., 2016; H. Li et
al., 2018; P. Ma et al., 2015; Xie et al., 2018; F. Zhang et al., 2015),
4 literatures reported the level of MDA(Y. Hu et al., 2016; H. Li et
al., 2018; P. Ma et al., 2015; Xie et al., 2018), 5 literatures reported
the level of IκBα(Y. Deng et al., 2016; Fu et al., 2018; L. Li et al.,
2014; Xiong et al., 2016; L. Zhang et al., 2017), 4 literatures reported
the level of Bcl-2 Level(H. Li et al., 2018; P. Ma et al., 2015; Xie et
al., 2018; F. Zhang et al., 2015), 3 literatures reported the level of
IFN-γ(Tao et al., 2013; X. Zhang et al., 2018; J. Zhou et al., 2011), 2
literatures reported the level of Bax-2(H. Li et al., 2018; Xie et al.,
2018), 2 literatures reported the level of Caspase-1(Su et al., 2018; L.
Zhang et al., 2017), 2 literatures reported the level of PPARα(Y. Deng
et al., 2016; Xiong et al., 2016), and 2 literatures reported the level
of PPARγ(Y. Deng et al., 2016; Xiong et al., 2016), 2 literatures
reported the level of NLRP3(Su et al., 2018; L. Zhang et al., 2017), and
2 literatures reported the level of p65 NF-κB(Y. Deng et al., 2016; L.
Zhang et al., 2017).
3.2 Study quality
Among the 19 articles included in the study, all articles describe
methods for randomizing animals into experimental and control groups. 6
articles described possible prognostic features and animal factors, 16
articles described methods of concealing the order of allocation, all
studies described random allocation of animal rooms, and 16 articles
reported blinding of trial participants, 12 articles described random
selection of animals for outcome assessment, 15 articles blinded outcome
assessment, and 8 articles reported the information of experimental
attrition and sample exclusion, and 10 articles reported the
completeness of the data, and no other sources of bias and selective
reporting were found in these 19 articles(Figure 4).