PLIN4 and metabolic syndrome: The authors [44] noted the upregulation of PLIN4 (perilipin 4, a protein involved in the storage of lipids within cells) and PKM GP (pyruvate kinase M1/2, an enzyme involved in glycolysis) expression in the absence of calorie restriction or substantial weight loss, which points to the possibility that 30-day IF may be highly effective in managing metabolic syndrome.