Mapping the evidence of hepatoprotective properties of Moringa oleifera from sub-Saharan African countries: a systematic review protocol

BACKGROUND: One of the most challenging health problems is liver disease, which can be caused by medications, toxic substances, and excessive consumption of alcohol. Liver problems can be also caused by infections, autoimmune disorders, and food. This study aims to establish evidence of the use of Moringa oleifera in sub-Saharan African countries to manage liver damage conditions in animals. METHODS: In vivo studies will include those in which the activity of the serum levels of hepatic enzymes alanine transaminase (ALT) or serum glutamate-pyruvate transaminase (SGPT), aspartate transaminase (AST) or serum glutamic oxaloacetic transaminase (SGOT), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and malondialdehyde (MDA) were measured after administering substances that induced liver injury as a primary outcome. The secondary outcome will include studies that measure the serum levels of hepatic enzymes (ALT, AST, GGT and ALP, SOD, CAT, and GR), free radical formation represented by MDA after administering the sub-Saharan Moringa oleifera, and decreases in their levels indicating the improvement of their activity. Search engines will include MEDLINE, CINAHL, PubMed, Google Scholar, SABINET, EBSCO, and WHO/African Index Medicus. The screened results will be grouped according to any noteworthy grouping variable, such as study characteristics. Data will be analyzed using Stata statistical software (Stata Corp V.14, TX, USA). Study data will be quantitatively synthesized by first assessing heterogeneity to examine whether the estimates from included studies could be pooled. Heterogeneity will be assessed by the chi-squared test on Cochran’s Q statistic, which will be quantified by I(2) values. DISCUSSION: Results from this protocol will give new insights into the Moringa oleifera plant for developing effective hepatoprotective drugs against liver damage. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018084698. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13643-019-1117-2) contains supplementary material, which is available to authorized users.