What Does Collagen Do?

Collagen Benefits

Collagen peptides are a class of biologically active peptides with a variety of biological functions that have been found to be beneficial to bones, joints and skin. In addition, it has anti-hypertensive, diabetic, antioxidant and antibacterial activities.

Prevention and treatment of osteoporosis

Osteoporosis (OP) is a systemic metabolic bone disease, one of the most common osteoarticular pathologies, characterised by reduced bone mineral density and increased fracture susceptibility. OP is mainly caused by oestrogen or nutrient deficiencies, aging and chronic diseases, and can therefore be classified as primary, idiopathic and secondary osteoporosis. Collagen peptides are used as a dietary supplement to improve bone and joint health and are a good supplement to prevent OP. Collagen peptides were found to promote osteoblast proliferation and differentiation in vitro and to increase bone mineral density and osteoblast alkaline phosphatase (ALP) activity in a dose-dependent manner after de-ovulation in rats. At the same time, it increased the organic matter content of the left femur, promoted the proliferation of osteoblasts, and decreased the water content of the left femur after de-ovulation in spontaneously hypertensive rats. Salmon collagen peptides from the sea can promote cartilage differentiation, lay the foundation for cartilage regeneration, increase serum osteocalcin levels, promote the proliferation of bone marrow stem cells and mature osteoblasts, and reduce osteoclasts. A clinical trial examining the risk of osteoporosis in menopausal women has found that a dietary supplement using a calcium-collagen peptide chelate improves blood biomarkers of bone mineral density and bone turnover in postmenopausal women.

Collagen for skin

Skin ageing factors are classified into extrinsic and intrinsic factors. Aging determined by external environmental factors and lifestyle is called exogenous skin aging, also known as skin photoaging, while aging determined by an individual's genetic make-up is called endogenous skin aging, also known as natural skin aging. Natural ageing causes dryness, thinning of the skin with fine wrinkles and periorbital hyperpigmentation, while photoageing causes coarse wrinkles, roughness and loss of elasticity of the skin, changes in the skin's barrier function, localised hyperpigmentation or dilated capillaries.

Intake of catfish skin collagen peptides reduces pathological changes in the uneven distribution, fracture and laxity and morphology of skin collagen fibres under UV irradiation, reduces transepidermal water loss, skin wrinkles and abnormal elastin fibres, promotes collagen synthesis, increases skin elasticity, and contributes to an increase in the content of Hyp and hyaluronic acid in skin tissues. In animal model experiments, it was found that ingestion of collagen peptides or Pro had no effect on the moisture and hyaluronic acid content of naturally aged mouse skin, but significantly reduced skin laxity, increased collagen fibre and collagen content, and normalized the ratio of type I and type III collagen in naturally aged skin. In addition, significant improvements in visual appearance, tissue structure and matrix homeostasis of mouse skin were found by gavage of collagen peptides in mice. It also maintains normal antioxidant indexes in animal skin and serum by increasing catalase, SOD, glutathione peroxidase activity and glutathione (GSH) content and decreasing malondialdehyde (MDA) and protein carbonyl content. In a study of healthy female subjects, researchers found that sustained administration of a supplement of fish-derived collagen peptides or other antioxidants for 90 days increased the thickness of naturally aging dermal papillae of the skin, the water content of the stratum corneum of the skin of the cheeks and the corners of the eyes, decreased the destruction of the skin's collagenous structure, reduced the pores of the skin, and reduced the periorbital hyperpigmentation and the skin's roughness in order to repair the skin's natural aging.

Figure 2. Collagen loss following intrinsic and extrinsic aging
(Source: Sibilla S, et al. 2015)

Prevention of type II diabetes

Diabetes mellitus (DM) is a metabolic disease caused by insulin resistance or lack of insulin secretion, and hyperglycemia is its main feature, of which the most common is type 2 diabetes mellitus (T2DM). Insulin resistance and pancreatic beta cell dysfunction are the main causes of T2DM. Several studies have found that salmon skin collagen peptide treatment for T2DM improves glucose metabolism and insulin sensitivity in T2DM rats by decreasing MDA formation associated with oxidative stress, increasing serum antioxidant activity SOD activity and GSH content, inhibiting inflammatory factor activity, and protecting pancreatic β-cells from apoptosis for the purpose of treating T2DM. Clinical trials of patients with T2DM and healthy subjects showed significant reductions in fasting blood glucose, mean arterial pressure and diastolic blood pressure, and significant reductions in total cholesterol and triglyceride, LDL, free fatty acid, and prostacyclin levels in the fish collagen peptide-treated group of patients, compared to the control group. However, HDL and adiponectin levels were elevated, and insulin sensitivity index and insulin secretion index levels were elevated. These results suggest that collagen peptides improve glucose and lipid metabolism in T2DM patients.

Collagen for hair growth

Alopecia is one of the common clinical disorders nowadays, which seriously affects the quality of life of patients. Its pathogenesis has not been fully elucidated and may be related to genetics, immunity, oxidative stress, microbiome, epigenetics, and other factors, and is the result of a multifactorial approach. Currently only minoxidil and finasteride are approved as treatments for hair loss. X Type VII collagen (COL17) is a transmembrane protein of the epidermal basal layer, which has the function of maintaining tight junctions between the epidermis and dermis to promote epidermal turnover and stabilize the basement membrane. It has been found that COL17 hydrolysis can cause miniaturization of hair follicles and ultimately lead to hair loss. Deficiency of COL17 induces alopecia through accumulation of DNA damage effects, imbalance of epidermal cell polarity, and inhibition of stem cell competition. Small molecule drugs that induce COL17 are yet to be further developed in the field of promoting hair regrowth.