These knowledge gaps are not reasons to dismiss the research
Maron and Michel, 2012)
It is known to reduce skin cell inflammation and dryness, and B12 is found to be effective for treating and preventing skin conditions like acne, psoriasis and eczema

A clinical study involving 8 participants showed that 250mg of glucosamine administered for 8 weeks increased the expression of type I and III collagen and hyaluronan synthase.48 In a blinded RCT (n=53), a dietary supplement containing glucosamine, minerals, and antioxidants significantly decreased the number of facial wrinkles and fine lines.49 Systemic Glutathione Glutathione has antioxidative, antitumor, antiviral, and antimelanogenic properties.50 Oral and intravenous formulations have been used to decrease skin pigmentation and photoaging, but 2 recent systematic reviews of the literature, including 3 RCTs, did not find sufficient evidence to recommend their use in this setting.50,51 A more recent RCT (n=124), not included in the above systematic reviews, showed that 250mg of glutathione combined with 500mg of l-cystine for 12 weeks significantly reduced solar lentigines and hyperpigmented macules in Asian women

This helps you translate millilitres into the markings you actually see on the syringe
Mechanistically, MOTS-c triggers activation of the cellular energy sensor AMPK (5 AMP-activated protein kinase), which in turn enhances glucose uptake and utilization in cells