Table 6.

In vivo effects of tilapia-derived peptide mixtures and protein hydrolysates ^a.

Sample	Effective Dosage (per kg Body Weight)	In Vivo Model	Key Findings	Reference
Collagen polypeptides (<3 kDa) prepared from tilapia skin using neutral protease and papain	500–2000 mg	Mouse model of aging induced by D-galactose	Alleviated reduction of SOD, CAT, and GSH-Px activities in liver and kidney tissues Decreased MDA levels in liver and kidney tissues Decreased serum LPO Suppressed the induction of protein expression of inducible nitric oxide synthase in liver and kidney tissues	[23]
Tilapia gelatin hydrolysate prepared with Properase E®	100–200 mg	UV-induced skin photoaging mice	Increased SOD, CAT, and GSH-Px activities Reduced MDA level Increased collagen deposition	[70,71]
Commercial tilapia collagen peptide powder, in combination with antioxidant supplements	Collagen peptide, 1.2 g; vitamin C, 100 mg; vitamin E, 2.66 mg; astaxanthin, 2.5 mg	UV-induced skin photoaging mice	Increased plasma SOD, GSH-Px, and CAT activities Reduced serum ROS and plasma MDA levels Reduced pro-inflammatory factors, IL-1α, IL-6, IL-10, IL-12, and TNF-α, in serum Increased Hyp and type I collagen contents	[24]
Tilapia skin collagen hydrolysate prepared with Alcalase®	0.85–1.70 g	Alloxan-induced diabetic mice	Increased pancreatic SOD and CAT, and reduced MDA levels High dose of peptides showed similar hypoglycemic activity as metformin, an anti-diabetic drug	[22]
Tilapia collagen peptide mixture TY001	20–60 g	STZ-induced diabetic mice	Increased SOD and CAT activities of wound tissues Enhanced wound healing Decreased blood glucose level Reduced level of serum pro-inflammatory cytokines IL-1β and IL-8 Increased level of serum anti-inflammatory IL-10 Increased Hyp contents and enhanced collagen deposition	[69]
Tilapia viscera hydrolysate extract prepared with Alcalase®	150–300 mg	DOCA-salt-induced hypertensive rats	Reduced MDA level in kidney Alleviated glomerular necrosis in renal tissues	[44]
Tilapia skin collagen hydrolysate prepared with Alcalase®	250–2500 mg	Mice subjected to exhaustive swimming assay	Increased serum SOD level Alleviated fatigue	[72]

^a CAT, catalase; DOCA, deoxycorticosterone acetate; GSH-Px, glutathione peroxidase; Hyp, hydroxyproline; IL, interleukin; LPO, lipid peroxidation; MDA, malondialdehyde; ROS, reactive oxygen species; SOD, superoxide dismutase; STZ, streptozotocin.