The evidence to support the use of Moringa?

1. The evidence to support the use of Moringa? Yuri Clement, PhD Professor of Pharmacology, UWI

2. Multiple Medicinal Uses • Antioxidant • Anticancer • Antidiabetic • Antihypertensive • Antihyperlipidaemic • Antipyretic • Antimicrobial • Hepatoprotectant

3. Secondary metabolites (medicinal/health benefits???) • Glucosinolates (4-O-(a-L-rhamnopyranosyloxy)-benzylglucosinolate; glucotropaeolin) • Flavonoids (quercetin, kaempferol, isorhamnetin) • Folates (5-formyl-5,6,7,8-tetrahydrofolic acid; 5,6,7,8-tetrahydrofolic acid; 10-Formylfolic acid) • Terpenoids • Carotenoids

4. Hierarchy of evidence Randomized Controlled Clinical trials (RCTs) Animal (in vivo) experiments Ex vivo experiments Cell culture (in vitro) experiments

5. Oxidative Stress

6. Antioxidant effects Cell cultures Human Embryonic Kidney-293 cells (non-cancer cell line) model using hydrogen peroxide-induced oxidative stress. Results: Leaf extract and isoquercetin (major phenolic component): ↓generation of reactive oxygen species ↑antioxidant enzyme mRNA expression Vongsak et al (2015) Planta Med 81(12-13):1084-9. In vitro assays and Free Radical scavenging capacity Adebayo et al (2015) J Basic Clin Physiol Pharmacol 26(5):491-9. Atawodi et al (2010) J Med Food 13(3):710-6. Tumer et al (2015) J Agric Food Chem 63(5):1505-13.

7. Antioxidant Effects (Clinical Trial) Randomized controlled crossover study 20 healthy volunteers Water (200mL) or dried extract (200mg in 200mL water) Blood samples taken at 30 min intervals over 2 hours: Results: ↑antioxidant capacity ↓biochemical marker of oxidative stress. Ngamukote et al (2016) Chin J Integr Med Dec 29.

8. Cell culture – Human Cancer Cell Lines Extracts, isolated “active ingredients” compared with control and standard anticancer drugs. Incubated up to 2 days. Cell viability tested using MTT (live cells convert yellow to purple)

9. Cell culture – Human Cancer Cell Lines Laryngeal cancer cell line • HEp-2 Ethyl acetate leaf extract (IC50 12.5µg/mL) Liver cancer cell line • HepG2 Isolated compounds • quercetin-3-O-glucoside (IC50 150µg/mL) • 4-(β-D-glucopyranosyl-1→4-α-L-rhamnopyranosyloxy)-benzyl isothiocyanate (IC50 45µg/mL) • Seed essential oil (IC50 751.µg/mL) Elsayed et al (2015) Asian Pac J Cancer Prev 16(11):4671-5. Krishnamurthy et al (2015) Indian J Exp Biol 53(2):98-103. Tiloke et al (2013) BMC Complement Altern Med 13:226. doi: 10.1186/1472-6882-13-226. Berkovich et al (2013) BMC Complement Altern Med 13:212. doi: 10.1186/1472-6882-13-212.

10. Cell culture – Human Cancer Cell Lines Lung cancer cell line • A549 Crude aqueous extract (166.7ug/mL) • cytotoxic by ↑oxidative stress, DNA fragmentation and programmed cell death. Pancreatic cancer cell lines • Panc-1, p34, COLO 357 Leaf extract cytotoxic from 0.75ug/mL. • Inhibited cell growth via programmed cell death pathways, and increased the efficacy of standard chemotherapy. Krishnamurthy et al (2015) Indian J Exp Biol 53(2):98-103. Tiloke et al (2013) BMC Complement Altern Med 13:226. doi: 10.1186/1472-6882-13-226. Berkovich et al (2013) BMC Complement Altern Med 13:212. doi: 10.1186/1472-6882-13-212.

11. Cell culture – Human Cancer Cell Lines Breast cancer cell lines • MDA-MB-231 & MCF-7 Leaf and bark extracts • 70-90% ↓ in colony formation • Seed extract had no significant anticancer properties. • MCF-7 Seed essential oil (IC50 226.1 µg/mL) Cervical cancer cell line • HeLa – seed essential oils (IC50 422.8 µg/mL). Al-Asmari et al (2015) PLoS One 10(8):e0135814. Elsayed et al (2015) Asian Pac J Cancer Prev 16(11):4671-5.

12. Cell culture – Human Cancer Cell Lines Colon cancer cell line • Caco-2 Isolated compounds • quercetin-3-O-glucoside (IC50 79µg/mL) • 4-(β-D-glucopyranosyl-1→4-α-L-rhamnopyranosyloxy)-benzyl isothiocyanate (IC50 60µg/mL) Maiyo et al (2016) Anticancer Agents Med Chem 16(5):648-56.

13. Animal study: Chemically-induced colon cancerBudda et al (2011) Asian Pac J Cancer Prev 12(12):3221-8. Colitis-associated colon cancer model: Rats given azoxymethane (AOM) and dextran sodium sulfate (DSS) to initiate and promote. Given boiled freeze-dried extract (1.5%, 3.0%, 6.0%) for 2 weeks before chemical treatment. Animals sacrificed after 20 weeks, colon harvested: • Histological examination • Biochemical markers of cancer initiation, promotion and progression Results: Dose-dependent reduction in number of tumors and biochemical markers of cancer initiation, promotion and progression

14. Clinical Evidence for cancer??? • No epidemiological studies • Population studies • Case-control studies • No clinical trials • For prevention • For treatment

15. Animal studies - Diabetes Alloxan-induced diabetic rats Four treatment groups: 300 or 600mg/kg methanol extract or metformin (100mg/kg) or saline for 6 weeks. Biochemical measurements in serum, liver and muscle. Results: Improved glucose tolerance ↑ insulin levels ↑glycogen synthesis Improved lipid profile Olayaki et al (2015) J Basic Clin Physiol Pharmacol 26(6):585-93. Similar results in: Abd El Latif et al (2014) Biochem Cell Biol 92(5):413-9.

16. Animal studies – DiabetesPaula et al (2017) Molecules 22(2). pii: E271. doi: 10.3390/molecules22020271 Alloxan-induced diabetic rats Protein isolate from crude leaf extract (100, 300 and 500mg/kg) given intraperitonally (ip). Blood glucose levels measured up to 5 hours. Results • Dose-dependent hypoglycaemic effect • 34% to 65% reduction in blood glucose levels at 500mg/kg • No effect on insulin levels • No effect when given orally

17. Animal studies - Diabetes STZ-induced diabetic rats Three treatment groups: 150 or 300 mg/kg methanol extract for 21 days or saline. Biochemical measurements in serum and pancreatic tissue Results: ↓fasting plasma glucose, ↑ insulin levels, ↑antioxidant levels and ↓ oxidative stress with reversed histopathological damage in pancreatic tissue. Gupta et al (2012) J Diabetes 4(2):164-71. Similar results in: Al-Malki et al (2015) Biomed Res Int doi: 10.1155/2015/381040. Yassa et al (2014) Acta Histochem 116(5):844-54.

18. Clinical evidence – Diabetes (Short term effects) Effect on post-prandial glucose (PPG) • Standardized meal given with and without Moringa compared with glucose challenge (75g) in untreated Type 2 diabetic patients. • Blood samples taken at 1- and 2-hour intervals after meal or challenge to measure blood glucose levels Results: Standardized meal given with moringa PPG levels 21%↓ compared with no supplementation. William et al (1993) Int J Food Sci Nutr 44:191-196.

19. Clinical evidence – Diabetes (Long terms effects) PPG levels and HbA1c Type 2 diabetic patients given moringa leaf powder (8g) for 40 days. Fasting and PPG measured before addition of moringa and after 40 days. Compared with untreated diabetics Results: ↓28% Fasting blood glucose ↓26% PPG No effect on insulin levels Kumari (2010) Bioscan 5(2):211-214 Fasting glucose and PPG • 60 Type 2 treated diabetics with or without 2 moringa tablets daily for 90 days. (Actual dose not given) • PPG levels and HbA1c measured at start and monthly until end of study. (Initial PPG levels and HbA1c higher in group given moringa) Results: • ↓29% PPG • HbA1c fell from 7.8% to 7.4% Ghiridhari et al (2011) Int J Health Nutr 2:1-5

20. Animal models – Hypertension Model: Spontaneously hypertensive rats Treatment: 750mg/kg seed powder or normal chow for 8 weeks. Measurements: Blood pressure and cardiac structure and function analysis. Results: No effect on blood pressure ↓nocturnal HR Improved cardiac diastolic function (↑ejection volume, ↑cardiac output) ↓left ventricular wall thickness Randriamboavonjy et al (2016) Am J Hypertens 29(7):873-81.

21. Clinical Evidence for hypertension??? • No epidemiological studies • Population studies • Case-control studies • No clinical trials • For prevention • For treatment

22. The need for good quality clinical trials

23. Randomized controlled clinical trial: The gold standard for testing in humans • Randomization – each patient has equal chance of being assigned to control or treated group. • Double-blinded – both patients and doctors unaware of whether assignment is to control or treated group. • Large sample size to detect statistical differences between control (placebo or standard drug/treatment) and treated patients

24. Conclusions • Most evidence from low level: cell culture and animal experiments • No long term clinical evidence that antioxidant effect provide long term benefits to prevent disease • No clinical evidence to support use for either cancer or hypertension • Clinical studies for diabetes have poor methodological quality: • Randomization? • Blinding? • Small sample sizes