Preclinical Evaluation of Protective Effects of Terpenoids Against Nanomaterial-Induced Toxicity: A Meta-Analysis

Terpenoids, the largest class of natural products, have been demonstrated to confer antioxidant, anti-inflammatory, anti-apoptotic, and antitumor activities. However, whether terpenoids benefit populations exposed to nanomaterials through these mechanisms remains unclear. This meta-analysis was to evaluate the effects of terpenoids in preclinical models with nanomaterial exposure. Electronic database searching identified 39 studies. The meta-analysis by Stata 15.0 showed that terpenoid supplementation significantly improved cell viability and altered oxidative stress (decreased ROS, NO, MDA, and TOC and increased SOD, CAT, GPx, GSH, GSH-Px, and TAC)-, inflammation (decreased IL-6, IL-1β, TNF-α, NF-κB, monocytes, and increased IL-10)-, apoptosis (reduced Bax, caspase-3, caspase-9, P53, and elevated Bcl-2)-, genotoxic (reduced tail length, % tail DNA, tail moment, DNA fragmentation, chromosomal aberration, and MNPCEs)-, liver function (reduced ALT, AST, and ALP)-, renal function (reduced creatinine, urea, and uric acid)-, reproductive function (increased sperm count, testosterone, Johnsen's score, and number of progeny)-, lipid profile (lower cholesterol, TG, LDL, and higher HDL)-, and carcinogenesis (downregulated AFP and CEA)-related biomarkers induced by nanomaterials. Subgroup analysis indicated that monoterpenoids and tetraterpenoids were particularly effective. Collectively, terpenoids may be a promising candidate for prevention of toxicities caused by nanomaterials.