Salivary proline-rich protein may reduce tannin-iron chelation: a systematic narrative review

Nutrition & Metabolism

Table 6 In vivo studies comparing PRP expression and non-heme iron availability with tannin ingestion

Study	Model	Intervention	Study conditions	Tannin concentration in challenge diet (g/kg)	Fe(diet)	n	Study duration	Measurement of bioavailability	PRP measurement
[70]	Sprague Dawley rats	Green tea	Control (acute and chronic)	28.6 g/kg green tea (nd)	20 mg/kg	6	7, 30 days	% absorption (⁵⁹Fe test meals), Hepatic non-heme iron	SDS-PAGE, MALDI-MS/MS,DIGE
			Acute gastric gavage			6	7 days
			Chronic gastric gavage			6	30 days
			Acute tea powder			6	7 days
			Chronic tea powder			6	30 days
[37]	Sprague Dawley rats	Black tea	Control	0.3 ± 0.0	35.9 ± 1.3	6	24 days	% absorption (⁵⁹Fe test meals), Hepatic non-heme iron	SDS-PAGE
			5% tea solids challenge tannin free diet	8.9 ± 0.5	35.9 ± 1.3	6	24 days
			5% tea solids +6% gelatin challenge tannin free diet	9.9 ± 0.7	35.9 ± 1.3	6	24 days
			5% tea solids chronic diet	8.9 ± 0.5^a	34.3 ± 1.5	6	24 days
			5% tea solids +6% gelatin chronic	9.9 ± 0.7^a	34.6 ± 1.0	6	24 days

^aSupplied as 25 g/kg in diet
SDS-PAGE sodium dodecyl polyacrylamide gel electrophoresis, MALDI-MS/MS Matrix-assisted laser desorption/ionization/mass spectrometry, DIGE difference gel electrophoresis

ISSN: 1743-7075