Pre-clinical efficacy of African medicinal plants used in the treatment of snakebite envenoming: A systematic review.

The World Health Organization has listed Snakebite Envenoming (SBE) as a priority neglected tropical disease, with a worldwide annual snakebite affecting 5.4 million people and injuring 2.7 million lives. In many parts of rural areas of Africa and Asia, medicinal plants have been used as alternatives to conventional antisnake venom (ASV) due in part to inaccessibility to hospitals. Systemic reviews (SR) of laboratory-based preclinical studies play an essential role in drug discovery. We conducted an SR to evaluate the relationship between interventional medicinal plants and their observed effects on venom-induced experiments. This SR was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The Modified collaborative approach to meta-analysis and review of animal data from experimental studies (CAMARADES) and SYRCLE's risk of bias tools were used to appraise the included studies. Data were searched online in Medline via PubMed, Embase via OVID, and Scopus. Studies reporting in vivo and in vitro pharmacological activities of African medicinal plants/extracts/constituents against venom-induced pathologies were identified and included for screening. Data from the included studies were extracted and synthesized. Ten studies reported statistically significant percentage protection (40-100%) of animals against venom-induced lethality compared with control groups that received no medicinal plant intervention. Sixteen studies reported significant effects (p ≤ 0.05) against venom-induced pathologies compared with the control group; these include hemolytic, histopathologic, necrotic, and anti-enzymatic effects. The plant family Fabaceae has the highest number of studies reporting its efficacy, followed by Annonaceae, Malvaceae, Combretaceae, Sterculiaceae, and Olacaceae. Some African medicinal plants are preclinically effective against venom-induced lethality, hematotoxicity, and cytotoxicity. The evidence was extracted from three in vitro studies, nine in vivo studies, and five studies that combined both in vivo and in vitro models. The effective plants belong to the Fabaceae family, followed by Malvaceae, and Annonaceae.

Preclinical efficacy of African medicinal plants used in the treatment of snakebite envenoming: a systematic review protocol.

BACKGROUND: Snakebite envenoming (SBE) is a high-priority, neglected, tropical disease that affects millions of people in developing countries annually. The only available standard drug used for the treatment of SBE is antisnake venom (ASV) which consists of immunoglobulins that have been purified from the plasma of animals hyper-immunized against snake venoms. The use of plants as alternatives for treatment of poisonous bites particularly snakebites is important in remote areas where there might be limited, or no access to hospitals and storage facilities for antivenom. The pharmacological activity of some of the medicinal plants used traditionally in the treatment of SBE have also been scientifically validated. METHOD: A systematic review will be conducted according to the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies checklist for study quality in animal/in vivo studies. The tool will be modified and validated to assess in vitro models and studies that combine in vivo and in vitro studies. The systematic review will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. English published articles on African medicinal plants used in the treatment of snakebite envenoming will be searched in Medline, Embase, and Scopus from 2000 to 2021. DISSEMINATION: The findings of the study will be communicated through publication in peer-reviewed journal and presentation at scientific conferences. Medicinal plants have been important sources for the development of many effective drugs currently available in orthodox medicine. Botanically derived medicines have played a major role in human societies throughout history. Plants components used in traditional medicine gained much attention by many toxinologists as a tool for designing potent antidotes against snake envenoming. Our systematic review will provide a synthesis of the literature on the efficacy of these medicinal plants. We will also appraise the prospects of African medicinal plants with pharmacologically demonstrated activity against snakebite and envenoming.

Protective effects of vitamin E on sodium arsenite-induced toxicity, testicular measurements and histopathological studies of testes in Teddy goat bucks.

The objective of this study was to investigate the toxic effects of arsenic on testicular measurements and histology of adult Teddy goats bucks and to examine whether these toxic effects are scavenged by vitamin E. Twelve adult Teddy goat bucks were divided randomly into three groups, A, B and C. Group A was kept as control, the B was given sodium arsenite 5 mg/kg BW per day, and group C was fed with vitamin E 200 mg/kg BW per day + arsenic 5 mg/kg BW per day. This treatment was continued for 84 days. Analysis of data revealed that the testicular measurements (scrotal circumference, width, length and weight) were significantly reduced in arsenic-treated animals, whereas there were ameliorating effects of vitamin E on these parameters. The major histopathological changes were present in the form of loss of germinal epithelium, atrophy of Leydig cells and vacuolations. Vitamin E in combination with sodium arsenite increased the active spermatogenesis as well as restoration of germinal epithelium. It can be concluded from the present findings that sodium arsenite causes toxicity in the male reproductive system of Teddy goat bucks with major changes in parenchyma of testes. Supplementation of vitamin E has protective effects on the toxicity of sodium arsenite on the reproductive system of male Teddy goat bucks.

RETRACTED: Synergistic effects of thymoquinone and curcumin on immune response and anti-viral activity against avian influenza virus (H9N2) in turkeys.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The authors retract the above paper due to: 1) conflict of interest among the authors; and 2) addition of coauthor Dr. Muhammad Younus without his knowledge or permission. The authors apologize for these two grave mistakes.

Alternative cannulation strategy for pediatric ECMO.

Vascular access in children who require extracorporeal membrane oxygenation (ECMO) support can be a challenging endeavor particularly in those who have undergone prior median sternotomies or interventional procedures. We present an alternative cannulation strategy that can be utilized in pediatric patients requiring ECMO that involves utilization of the iliac vein via a retroperitoneal approach.

Leaf biochemistry of Lycopersicon esculentum Mill. at different stages of plant development as affected by mercury treatment.

The effect of mercury (Hg) on the biochemical parameters of Lycopersicon esculentum Mill leaf was studied. Application of mercuric chloride in varying concentrations (0.5, 1.0, 1.5 and 2.0 mM HgCl2 kg(-1) sand) caused significant reduction that went up to 89% and 72% chlorophyll a and chlorophyll b contents respectively (at flowering stage), 69% in carotenoid content, 64% in total soluble protein content and 91% in nitrate reductase activity (all at post-flowering stage). The amounts of nitrate and proline increased maximally (151% and 143% respectively) at the flowering stage, whereas total soluble sugar enhanced by 57% at the post-flowering stage. Changes observed in most of the parameters, were concentration dependent. Such studies seem to be able to discover suitable bioindicators of heavy metal pollution.

Dietary pectin and calcium inhibit colonic proliferation in vivo by differing mechanisms.

Diet plays an important role in promoting and/or preventing colon cancer; however, the effects of specific nutrients remain uncertain because of the difficulties in correlating epidemiological and basic observations. Transmissible murine colonic hyperplasia (TMCH) induced by Citrobacter rodentium, causes significant hyperproliferation and hyperplasia in the mouse distal colon and increases the risk of subsequent neoplasia. We have recently shown that TMCH is associated with an increased abundance of cellular beta-catenin and its nuclear translocation coupled with up-regulation of its downstream targets, c-myc and cyclin D1. In this study, we examined the effects of two putatively protective nutrients, calcium and soluble fibre pectin, on molecular events linked to proliferation in the colonic epithelium during TMCH. Dietary intervention incorporating changes in calcium [high (1.0%) and low (0.1%)] and alterations in fibre content (6% pectin and fibre-free) were compared with the standard AIN-93 diet (0.5% calcium, 5% cellulose), followed by histomorphometry and immunochemical assessment of potential oncogenes. Dietary interventions did not alter the time course of Citrobacter infection. Both 1.0% calcium and 6% pectin diet inhibited increases in proliferation and crypt length typically seen in TMCH. Neither the low calcium nor fibre-free diets had significant effect. Pectin diet blocked increases in cellular beta-catenin, cyclin D1 and c-myc levels associated with TMCH by 70%, whereas neither high nor low calcium diet had significant effect on these molecules. Diets supplemented with either calcium or pectin therefore, exert anti-proliferative effects in mouse distal colon involving different molecular pathways. TMCH is thus a diet-sensitive model for examining the effect of specific nutrients on molecular characteristics of the pre-neoplastic colonic epithelium.